cuticleDB: a relational database of Arthropod cuticular proteins

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Willis Judith H

2004-09-01

Full Text Available Abstract Background The insect exoskeleton or cuticle is a bi-partite composite of proteins and chitin that provides protective, skeletal and structural functions. Little information is available about the molecular structure of this important complex that exhibits a helicoidal architecture. Scores of sequences of cuticular proteins have been obtained from direct protein sequencing, from cDNAs, and from genomic analyses. Most of these cuticular protein sequences contain motifs found only in arthropod proteins. Description cuticleDB is a relational database containing all structural proteins of Arthropod cuticle identified to date. Many come from direct sequencing of proteins isolated from cuticle and from sequences from cDNAs that share common features with these authentic cuticular proteins. It also includes proteins from the Drosophila melanogaster and the Anopheles gambiae genomes, that have been predicted to be cuticular proteins, based on a Pfam motif (PF00379 responsible for chitin binding in Arthropod cuticle. The total number of the database entries is 445: 370 derive from insects, 60 from Crustacea and 15 from Chelicerata. The database can be accessed from our web server at http://bioinformatics.biol.uoa.gr/cuticleDB. Conclusions CuticleDB was primarily designed to contain correct and full annotation of cuticular protein data. The database will be of help to future genome annotators. Users will be able to test hypotheses for the existence of known and also of yet unknown motifs in cuticular proteins. An analysis of motifs may contribute to understanding how proteins contribute to the physical properties of cuticle as well as to the precise nature of their interaction with chitin.

Pathogenicity of Beauveria bassiana and production of cuticle ...

African Journals Online (AJOL)

aghomotsegin

2013-11-13

Nov 13, 2013 ... cuticle-degrading enzymes in the presence of Diatraea saccharalis cuticle .... the bioassays, each larva was confined individually in plastic containers (17 x 21 x 25 ..... nism (virus, bacteria and protozoa). Only entomo-patho-.

Comparative analysis of genome maintenance genes in naked mole rat, mouse, and human.

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MacRae, Sheila L; Zhang, Quanwei; Lemetre, Christophe; Seim, Inge; Calder, Robert B; Hoeijmakers, Jan; Suh, Yousin; Gladyshev, Vadim N; Seluanov, Andrei; Gorbunova, Vera; Vijg, Jan; Zhang, Zhengdong D

2015-04-01

Genome maintenance (GM) is an essential defense system against aging and cancer, as both are characterized by increased genome instability. Here, we compared the copy number variation and mutation rate of 518 GM-associated genes in the naked mole rat (NMR), mouse, and human genomes. GM genes appeared to be strongly conserved, with copy number variation in only four genes. Interestingly, we found NMR to have a higher copy number of CEBPG, a regulator of DNA repair, and TINF2, a protector of telomere integrity. NMR, as well as human, was also found to have a lower rate of germline nucleotide substitution than the mouse. Together, the data suggest that the long-lived NMR, as well as human, has more robust GM than mouse and identifies new targets for the analysis of the exceptional longevity of the NMR. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Apple cuticle: the perfect interface

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Curry, Eric; Arey, Bruce

2010-06-01

The domestic apple might well be called an 'extreme' fruit. In the arid Northwest United States, the fruit often tolerates surface temperatures ranging from -2 °C in the early spring to 50 °C in the heat of summer, and again to -2 °C during controlled postharvest storage for up to 12 months. During its 18-month existence, the apple maintains a cuticle that is dynamic and environmentally responsive to protect against 1) cellular water loss during desiccation stress and 2) excessive uptake of standing surface moisture. Physiological disorders of the peel such as russeting, cracking, splitting, flecking and lenticel marking, develop as epidermal cells respond to rapid changes in ambient conditions at specific developmental stages during the growing season. Resultant market losses underlie research investigating the nature of apple cuticle growth and development. Ultrastructural analysis of the pro-cuticle using scanning electron microscopy indicates an overlapping network of lipid-based distally-elongating microtubules--produced by and connected to epidermal cells--which co-polymerize to form an organic solvent-insoluble semi-permeable cutin matrix. Microtubule elongation, aggregation, and polymerization function together as long as the fruit continues to enlarge. The nature of lipid transport from the epidermal cells through the cell wall to become part of the cuticular matrix was explored using an FEI Helios NanoLabTM DualBeamTM focused ion beam/scanning electron microscope on chemically- and cryo-fixed peel tissue from mature or freshly harvested apples. Based on microtubule dimensions, regular projections found at the cell/cuticle interface suggest an array of microtubule-like structures associated with the epidermal cell.

Are naked singularities really visible

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Calvani, M [Padua Univ. (Italy). Ist. di Astronomia; De Felice, F [Alberta Univ., Edmonton (Canada); Nobili, L [Padua Univ. (Italy). Ist. di Fisica

1978-12-09

The question whether a Kerr naked singularity is actually visible from infinity is investigated; it is shown that in fact any signal which could be emitted from the singularity is infinitely red-shifted. This implies that naked singularities would be indistinguishable from a black hole.

Gene expression and morphogenesis during the deposition of Drosophila wing cuticle.

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Adler, Paul N

2017-07-03

The exoskeleton of insects and other arthropods is a very versatile material that is characterized by a complex multilayer structure. In Sobala and Adler (2016) we analyzed the process of wing cuticle deposition by RNAseq and electron microscopy. In this extra view we discuss the unique aspects of the envelope the first and most outermost layer and the gene expression program seen at the end of cuticle deposition. We discussed the role of undulae in the deposition of cuticle and how the hydrophobicity of wing cuticle arises.

Chlorinated tyrosine derivatives in insect cuticle

DEFF Research Database (Denmark)

Andersen, Svend Olav

2004-01-01

A method for quantitative measurement of 3-monochlorotyrosine and 3,5-dichlorotyrosine in insect cuticles is described, and it is used for determination of their distribution in various cuticular regions in nymphs and adults of the desert locust, Schistocerca gregaria. The two chlorinated tyrosine......, not-yet sclerotized cuticle of adult femur and tibia, the amounts increased rapidly during the first 24 h after ecdysis and more slowly during the next two weeks. Control analyses using stable isotope dilution mass spectrometry have confirmed that the chlorinated tyrosines are not artifacts formed...

Naked singularity, firewall, and Hawking radiation.

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Zhang, Hongsheng

2017-06-21

Spacetime singularity has always been of interest since the proof of the Penrose-Hawking singularity theorem. Naked singularity naturally emerges from reasonable initial conditions in the collapsing process. A recent interesting approach in black hole information problem implies that we need a firewall to break the surplus entanglements among the Hawking photons. Classically, the firewall becomes a naked singularity. We find some vacuum analytical solutions in R n -gravity of the firewall-type and use these solutions as concrete models to study the naked singularities. By using standard quantum theory, we investigate the Hawking radiation emitted from the black holes with naked singularities. Here we show that the singularity itself does not destroy information. A unitary quantum theory works well around a firewall-type singularity. We discuss the validity of our result in general relativity. Further our result demonstrates that the temperature of the Hawking radiation still can be expressed in the form of the surface gravity divided by 2π. This indicates that a naked singularity may not compromise the Hakwing evaporation process.

Helicoidal microstructure of Scarabaei cuticle and biomimetic research

International Nuclear Information System (INIS)

Chen, B.; Peng, X.; Cai, C.; Niu, H.; Wu, X.

2006-01-01

Insect cuticles as a natural biocomposite include many favorable microstructures which have been refined over centuries and endow the cuticles excellent mechanical and physical properties, such as light weight, high strength and toughness, etc. The various microstructures of a Scarabaei cuticle are investigated with a scanning electronic microscope and reported in this paper. It is found that the cuticle is a kind of fiber-reinforced biocomposite composed of chitin-fiber layers and sclerous protein matrixes. Different chitin-fiber layers have different orientations, composed of crossed and helicoidal structures at different location. In the helicoidal structure, each fiber layer rotates with an almost fixed angle against its neighboring layer. The maximum pullout energy of the helicoidal structure is analyzed based on the representative model of the structure. The result shows that the pullout energy of the helicoidal structure is markedly larger than that of the conventional 0 o -structure. A biomimetic composite with the observed helicoidal structure is designed and fabricated. A comparative test shows that the fracture toughness of the biomimetic composite is markedly larger than that of the 0 o -layer composite

Quantum dress for a naked singularity

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Marc Casals

2016-09-01

Full Text Available We investigate semiclassical backreaction on a conical naked singularity space–time with a negative cosmological constant in (2+1-dimensions. In particular, we calculate the renormalized quantum stress–energy tensor for a conformally coupled scalar field on such naked singularity space–time. We then obtain the backreacted metric via the semiclassical Einstein equations. We show that, in the regime where the semiclassical approximation can be trusted, backreaction dresses the naked singularity with an event horizon, thus enforcing (weak cosmic censorship.

Genome Stability Maintenance in Naked Mole-Rat.

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Petruseva, I O; Evdokimov, A N; Lavrik, O I

2017-01-01

The naked mole-rat ( Heterocephalus glaber ) is one of the most promising models used to study genome maintenance systems, including the effective repair of damage to DNA. The naked mole-rat is the longest lived rodent species, which is extraordinarily resistant to cancer and has a number of other unique phenotypic traits. For at least 80% of its lifespan, this animal shows no signs of aging or any increased likelihood of death and retains the ability to reproduce. The naked mole-rat draws the heightened attention of researchers who study the molecular basis of lengthy lifespan and cancer resistance. Despite the fact that the naked mole-rat lives under genotoxic stress conditions (oxidative, etc.), the main characteristics of its genome and proteome are a high stability and effective functioning. Replicative senescence in the somatic cells of naked mole-rats is missing, while an additional p53/pRb-dependent mechanism of early contact inhibition has been revealed in its fibroblasts, which controls cell proliferation and its mechanism of arf- dependent aging. The unique traits of phenotypic and molecular adaptations found in the naked mole-rat speak to a high stability and effective functioning of the molecular machinery that counteract damage accumulation in its genome. This review analyzes existing results in the study of the molecular basis of longevity and high cancer resistance in naked mole-rats.

The Gene Expression Program for the Formation of Wing Cuticle in Drosophila.

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Lukasz F Sobala

2016-05-01

Full Text Available The cuticular exoskeleton of insects and other arthropods is a remarkably versatile material with a complex multilayer structure. We made use of the ability to isolate cuticle synthesizing cells in relatively pure form by dissecting pupal wings and we used RNAseq to identify genes expressed during the formation of the adult wing cuticle. We observed dramatic changes in gene expression during cuticle deposition, and combined with transmission electron microscopy, we were able to identify candidate genes for the deposition of the different cuticular layers. Among genes of interest that dramatically change their expression during the cuticle deposition program are ones that encode cuticle proteins, ZP domain proteins, cuticle modifying proteins and transcription factors, as well as genes of unknown function. A striking finding is that mutations in a number of genes that are expressed almost exclusively during the deposition of the envelope (the thin outermost layer that is deposited first result in gross defects in the procuticle (the thick chitinous layer that is deposited last. An attractive hypothesis to explain this is that the deposition of the different cuticle layers is not independent with the envelope instructing the formation of later layers. Alternatively, some of the genes expressed during the deposition of the envelope could form a platform that is essential for the deposition of all cuticle layers.

Timed Knickkopf function is essential for wing cuticle formation in Drosophila melanogaster.

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Li, Kaixia; Zhang, Xubo; Zuo, Ying; Liu, Weimin; Zhang, Jianzhen; Moussian, Bernard

2017-10-01

The insect cuticle is an extracellular matrix that consists of the polysaccharide chitin, proteins, lipids and organic molecules that are arranged in distinct horizontal layers. In Drosophila melanogaster, these layers are not formed sequentially, but, at least partially, at the same time. Timing of the underlying molecular mechanisms is conceivably crucial for cuticle formation. To study this issue, we determined the time period during which the function of Knickkopf (Knk), a key factor of chitin organization, is required for wing cuticle differentiation in D. melanogaster. Although knk is expressed throughout metamorphosis, we demonstrate that its expression 30 h prior and 48 h after pupariation is essential for correct wing cuticle formation. In other words, expression beyond this period is futile. Importantly, manipulation of Knk expression during this time causes wing bending suggesting an effect of Knk amounts on the physical properties of the wing cuticle. Manipulation of Knk expression also interferes with the structure and function of the cuticle surface. First, we show that the shape of surface nano-structures depends on the expression levels of knk. Second, we find that cuticle impermeability is compromised in wings with reduced knk expression. In summary, despite the extended supply of Knk during metamorphosis, controlled amounts of Knk are important for correct wing cuticle differentiation and function in a concise period of time. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fourier transform IR studies on the interaction of selected chemicals with isolated cuticles

International Nuclear Information System (INIS)

Luque, P.; Ramirez, F.J.; Heredia, A.; Bukovac, M.J.

1994-01-01

It is known that the plant cuticle represents the first barrier that must be overcome by any chemical reaching the plant surface from the atmosphere before entering the plant. Because of the importance of the cuticle as a barrier to penetration of a wide variety of compounds, its morphology, chemistry, and permeability have been extensively studied. However, only limited information is available on the nature of functional chemical groups present and their interaction and role during the penetration process. The usefulness of in situ Fourier transform infrared spectroscopy studies in identifying functional groups present in isolated cuticles is described and their relationships to the structure of the cuticular membrane are discussed. Applications of infrared spectroscopy on the presence and role of phenolics in the cuticle structure and during the cuticle development, nitrogen oxide binding to isolated cuticles, and the interactions between selected chemical probes during sorption by the cuticle are also described. (orig.)

Hypofunctional TrkA Accounts for the Absence of Pain Sensitization in the African Naked Mole-Rat.

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Omerbašić, Damir; Smith, Ewan St J; Moroni, Mirko; Homfeld, Johanna; Eigenbrod, Ole; Bennett, Nigel C; Reznick, Jane; Faulkes, Chris G; Selbach, Matthias; Lewin, Gary R

2016-10-11

The naked mole-rat is a subterranean rodent lacking several pain behaviors found in humans, rats, and mice. For example, nerve growth factor (NGF), an important mediator of pain sensitization, fails to produce thermal hyperalgesia in naked mole-rats. The sensitization of capsaicin-sensitive TRPV1 ion channels is necessary for NGF-induced hyperalgesia, but naked mole-rats have fully functional TRPV1 channels. We show that exposing isolated naked mole-rat nociceptors to NGF does not sensitize TRPV1. However, the naked mole-rat NGF receptor TrkA displays a reduced ability to engage signal transduction pathways that sensitize TRPV1. Between one- and three-amino-acid substitutions in the kinase domain of the naked mole-rat TrkA are sufficient to render the receptor hypofunctional, and this is associated with the absence of heat hyperalgesia. Our data suggest that evolution has selected for a TrkA variant that abolishes a robust nociceptive behavior in this species but is still compatible with species fitness. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Hypofunctional TrkA Accounts for the Absence of Pain Sensitization in the African Naked Mole-Rat

Directory of Open Access Journals (Sweden)

Damir Omerbašić

2016-10-01

Full Text Available The naked mole-rat is a subterranean rodent lacking several pain behaviors found in humans, rats, and mice. For example, nerve growth factor (NGF, an important mediator of pain sensitization, fails to produce thermal hyperalgesia in naked mole-rats. The sensitization of capsaicin-sensitive TRPV1 ion channels is necessary for NGF-induced hyperalgesia, but naked mole-rats have fully functional TRPV1 channels. We show that exposing isolated naked mole-rat nociceptors to NGF does not sensitize TRPV1. However, the naked mole-rat NGF receptor TrkA displays a reduced ability to engage signal transduction pathways that sensitize TRPV1. Between one- and three-amino-acid substitutions in the kinase domain of the naked mole-rat TrkA are sufficient to render the receptor hypofunctional, and this is associated with the absence of heat hyperalgesia. Our data suggest that evolution has selected for a TrkA variant that abolishes a robust nociceptive behavior in this species but is still compatible with species fitness.

Stiffness distribution in insect cuticle: a continuous or a discontinuous profile?

Science.gov (United States)

Rajabi, H; Jafarpour, M; Darvizeh, A; Dirks, J-H; Gorb, S N

2017-07-01

Insect cuticle is a biological composite with a high degree of complexity in terms of both architecture and material composition. Given the complex morphology of many insect body parts, finite-element (FE) models play an important role in the analysis and interpretation of biomechanical measurements, taken by either macroscopic or nanoscopic techniques. Many previous studies show that the interpretation of nanoindentation measurements of this layered composite material is very challenging. To develop accurate FE models, it is of particular interest to understand more about the variations in the stiffness through the thickness of the cuticle. Considering the difficulties of making direct measurements, in this study, we use the FE method to analyse previously published data and address this issue numerically. For this purpose, sets of continuous or discontinuous stiffness profiles through the thickness of the cuticle were mathematically described. The obtained profiles were assigned to models developed based on the cuticle of three insect species with different geometries and layer configurations. The models were then used to simulate the mechanical behaviour of insect cuticles subjected to nanoindentation experiments. Our results show that FE models with discontinuous exponential stiffness gradients along their thickness were able to predict the stress and deformation states in insect cuticle very well. Our results further suggest that, for more accurate measurements and interpretation of nanoindentation test data, the ratio of the indentation depth to cuticle thickness should be limited to 7% rather than the traditional '10% rule'. The results of this study thus might be useful to provide a deeper insight into the biomechanical consequences of the distinct material distribution in insect cuticle and also to form a basis for more realistic modelling of this complex natural composite. © 2017 The Author(s).

Collagenous and other organizations in mature annelid cuticle and epidermis.

Science.gov (United States)

Humphreys, S; Porter, K R

1976-05-01

The mature annelid cuticle contains orthogonally oriented collagen in a matrix capped superficially by a dense epicuticle with external corpuscles. The underlying epidermis is a simple columnar epithelium with two major cell types, mucous-secreting cells which secrete through channels in the cuticle to the exterior of the worm, and "supportive" cells which presumably produce and increase the cuticle by secreting into it. The structures of supportive cells, previously interpreted as specialized for establishing interfibrillar collagen order, are revealed by glutaraldehyde fixation as common cellular components without the qualities deemed useful to align collagen. Cell processes which penetrate and sometimes pass completely through the cuticle are not stable, not in geometric order, and lack cilia-like structure. Cilia, unlike the ubiquitous cellular processes, are highly restricted to regions of the epidermis with specialized functions. Cellular control, or other control, of collagen fibrillogenesis remains unestablished.

Timelike naked singularity

International Nuclear Information System (INIS)

Goswami, Rituparno; Joshi, Pankaj S.; Vaz, Cenalo; Witten, Louis

2004-01-01

We construct a class of spherically symmetric collapse models in which a naked singularity may develop as the end state of collapse. The matter distribution considered has negative radial and tangential pressures, but the weak energy condition is obeyed throughout. The singularity forms at the center of the collapsing cloud and continues to be visible for a finite time. The duration of visibility depends on the nature of energy distribution. Hence the causal structure of the resulting singularity depends on the nature of the mass function chosen for the cloud. We present a general model in which the naked singularity formed is timelike, neither pointlike nor null. Our work represents a step toward clarifying the necessary conditions for the validity of the Cosmic Censorship Conjecture

Biodegradation of the chitin-protein complex in crustacean cuticle

Science.gov (United States)

Artur, Stankiewicz B.; Mastalerz, Maria; Hof, C.H.J.; Bierstedt, A.; Flannery, M.B.; Briggs, D.E.G.; Evershed, R.P.

1998-01-01

Arthropod cuticles consist predominantly of chitin cross-linked with proteins. While there is some experimental evidence that this chitin-protein complex may resist decay, the chemical changes that occur during degradation have not been investigated in detail. The stomatopod crustacean Neogonodactylus oerstedii was decayed in the laboratory under anoxic conditions. A combination of pyrolysis-gas chromatography/mass spectrometry and FTIR revealed extensive chemical changes after just 2 weeks that resulted in a cuticle composition dominated by chitin. Quantitative analysis of amino acids (by HPLC) and chitin showed that the major loss of proteins and chitin occurred between weeks 1 and 2. After 8 weeks tyrosine, tryptophan and valine are the most prominent amino acid moieties, showing their resistance to degradation. The presence of cyclic ketones in the pyrolysates indicates that mucopolysaccharides or other bound non-chitinous carbohydrates are also resistant to decay. There is no evidence of structural degradation of chitin prior to 8 weeks when FTIR revealed a reduction in chitin-specific bands. The chemical changes are paralleled by structural changes in the cuticle, which becomes an increasingly open structure consisting of loose chitinous fibres. The rapid rate of decay in the experiments suggests that where chitin and protein are preserved in fossil cuticles degradation must have been inhibited.Arthropod cuticles consist predominantly of chitin cross-linked with proteins. While there is some experimental evidence that this chitin-protein complex may resist decay, the chemical changes that occur during degradation have not been investigated in detail. The stomatopod crustacean Neogonodactylus oerstedii was decayed in the laboratory under anoxic conditions. A combination of pyrolysis-gas chromatography/mass spectrometry and FTIR revealed extensive chemical changes after just 2 weeks that resulted in a cuticle composition dominated by chitin. Quantitative

Effect of egg washing on the cuticle quality of brown and white table eggs.

Science.gov (United States)

Leleu, S; Messens, W; De Reu, K; De Preter, S; Herman, L; Heyndrickx, M; De Baerdemaeker, J; Michiels, C W; Bain, M

2011-10-01

Egg washing is currently not permitted within the European Union, with few exceptions. This is mainly because there are concerns that cuticle damage could occur during or after the washing process, as a result of a suboptimal operation. In this study, the cuticle coverage levels of 400 washed or unwashed eggs, derived from either a brown or a white egg-laying flock at the end of lay, were compared. The eggs from older hens inherently have poorer cuticle coverage and as a result arguably constitute a greater risk to consumer safety if they are then washed. Thus, the effects of the washing procedure used in this study on cuticle quality were tested under the worst-case scenario. A standard Swedish egg washing process was used. The cuticle coverage of the eggs was assessed by a colorimeter by quantifying the color difference before and after staining with Tartrazine and Green S. The cuticle of an additional 30 eggs from each of the four groups was then visually assessed by scanning electron microscopy. The staining characteristics of the cuticle varied greatly within each group of eggs and showed that the washing process did not lead to cuticle damage. Scanning electron microscopy confirmed that there was no irreversible damage to the cuticle of the washed eggs and that it was not possible to correctly assign the treatment (washed or not) based on a visual assessment. In conclusion, no evidence could be found to suggest that the washing procedure used in this investigation irreversibly changed the quality of the cuticle.

Comparative ultrastructure of the cuticle of trichostrongyle nematodes.

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Beveridge, I; Durette-Desset, M C

1994-09-01

The ultrastructure of the cuticle was examined in Austrostrongylus victoriensis, Patricialina birdi and Woolleya monodelphis (Herpetostrongylidae) from marsupials, Paraustrostrongylus ratti (Herpetostrongylidae) from rodents, Nippostrongylus magnus and Odilia bainae (Heligmonellidae) from rodents, Cooperia oncophora and Camelostrongylus mentulatus (Trichostrongylidae) from ruminants, and Nematodirus spathiger (Molineidae) from ruminants. The principal cuticular layers described previously were present in all species investigated. Major differences in the shape and composition of cuticular struts were observed as well as differences in components of the median zone of the cuticle, including the fluid-filled regions present in several species. Several different types of strut were observed. Although strut structure within the Heligmonellidae appeared to be constant, there were variations within both the Herpetostrongylidae and Trichostrongylidae. In Nem. spathiger the cuticular ridges lacked struts. The diversity of structures found in the species examined suggests that more extensive comparative studies of the trichostrongyle cuticle are warranted.

Hypersensitivity to contact inhibition provides a clue to cancer resistance of naked mole-rat.

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Seluanov, Andrei; Hine, Christopher; Azpurua, Jorge; Feigenson, Marina; Bozzella, Michael; Mao, Zhiyong; Catania, Kenneth C; Gorbunova, Vera

2009-11-17

The naked mole-rat is the longest living rodent with a maximum lifespan exceeding 28 years. In addition to its longevity, naked mole-rats have an extraordinary resistance to cancer as tumors have never been observed in these rodents. Furthermore, we show that a combination of activated Ras and SV40 LT fails to induce robust anchorage-independent growth in naked mole-rat cells, while it readily transforms mouse fibroblasts. The mechanisms responsible for the cancer resistance of naked mole-rats were unknown. Here we show that naked mole-rat fibroblasts display hypersensitivity to contact inhibition, a phenomenon we termed "early contact inhibition." Contact inhibition is a key anticancer mechanism that arrests cell division when cells reach a high density. In cell culture, naked mole-rat fibroblasts arrest at a much lower density than those from a mouse. We demonstrate that early contact inhibition requires the activity of p53 and pRb tumor suppressor pathways. Inactivation of both p53 and pRb attenuates early contact inhibition. Contact inhibition in human and mouse is triggered by the induction of p27(Kip1). In contrast, early contact inhibition in naked mole-rat is associated with the induction of p16(Ink4a). Furthermore, we show that the roles of p16(Ink4a) and p27(Kip1) in the control of contact inhibition became temporally separated in this species: the early contact inhibition is controlled by p16(Ink4a), and regular contact inhibition is controlled by p27(Kip1). We propose that the additional layer of protection conferred by two-tiered contact inhibition contributes to the remarkable tumor resistance of the naked mole-rat.

Cuticle thickening associated with pyrethroid resistance in the major malaria vector Anopheles funestus

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Coetzee M

2010-08-01

Full Text Available Abstract Background Malaria in South Africa is primarily transmitted by Anopheles funestus Giles. Resistance to pyrethroid insecticides in An. funestus in northern Kwazulu/Natal, South Africa, and in neighbouring areas of southern Mozambique enabled populations of this species to increase their ranges into areas where pyrethroids were being exclusively used for malaria control. Pyrethroid resistance in southern African An. funestus is primarily conferred by monooxygenase enzyme metabolism. However, selection for this resistance mechanism is likely to have occurred in conjunction with other factors that improve production of the resistance phenotype. A strong candidate is cuticle thickening. This is because thicker cuticles lead to slower rates of insecticide absorption, which is likely to increase the efficiency of metabolic detoxification. Results Measures of mean cuticle thickness in laboratory samples of female An. funestus were obtained using scanning electron microscopy (SEM. These females were drawn from a laboratory colony carrying the pyrethroid resistance phenotype at a stable rate, but not fixed. Prior to cuticle thickness measurements, these samples were characterised as either more or less tolerant to permethrin exposure in one experiment, and either permethrin resistant or susceptible in another experiment. There was a significant and positive correlation between mean cuticle thickness and time to knock down during exposure to permethrin. Mean cuticle thickness was significantly greater in those samples characterised either as more tolerant or resistant to permethrin exposure compared to those characterised as either less tolerant or permethrin susceptible. Further, insecticide susceptible female An. funestus have thicker cuticles than their male counterparts. Conclusion Pyrethroid tolerant or resistant An. funestus females are likely to have thicker cuticles than less tolerant or susceptible females, and females generally have

Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia, B1P 6L2 (Canada); D' Angelo, Jose A. [IANIGLA, CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, IN, 47405-2208 (United States); Cleal, Christopher J. [Department of Biodiversity and Systematic Biology, National Museum of Wales, Cathays Park, Cardiff, CF10 3NP (United Kingdom); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

2010-11-01

In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond. Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season. This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. (author)

Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

Science.gov (United States)

Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Cleal, C.J.; Keefe, D.

2010-01-01

In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond.Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season.This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. ?? 2010 Elsevier B.V.

Breeding for cuticle-associated traits in crop species: traits, targets, and strategies.

Science.gov (United States)

Petit, Johann; Bres, Cécile; Mauxion, Jean-Philippe; Bakan, Bénédicte; Rothan, Christophe

2017-11-09

Improving crop productivity and quality while promoting sustainable agriculture have become major goals in plant breeding. The cuticle is a natural film covering the aerial organs of plants and consists of lipid polyesters covered and embedded with wax. The cuticle protects plants against water loss and pathogens and affects traits with strong impacts on crop quality such as, for horticultural crops, fruit brightness, cracking, russeting, netting, and shelf life. Here we provide an overview of the most important cuticle-associated traits that can be targeted for crop improvement. To date, most studies on cuticle-associated traits aimed at crop breeding have been done on fleshy fruits. Less information is available for staple crops such as rice, wheat or maize. Here we present new insights into cuticle formation and properties resulting from the study of genetic resources available for the various crop species. Our review also covers the current strategies and tools aimed at exploiting available natural and artificially induced genetic diversity and the technologies used to transfer the beneficial alleles affecting cuticle-associated traits to commercial varieties. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

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Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

2016-03-01

The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

Ultrastructure of cuticle deposited inPlodia interpunctella wing discs after variousβ-ecdysone treatments in vitro.

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Dutkowski, A B; Oberlander, H; Leach, C E

1977-06-01

Wing discs of the Indian meal moth may be cultured for extended periods in vitro. The discs produced a tanned cuticle after continuous incubation with β-ecdysone in medium conditioned with fat body or after a 24-h pulse incubation with β-ecdysone in plain medium. We investigated the ultrastructure of the cuticle deposited by such discs. We found that the treatment that produced the most complete cuticle in vitro was the 24-h pulse of hormone. We observed that cuticle formation in vitro was not "all-or-none." Depending on culture conditions, discs produced cuticulin only, complete epicuticle, epicuticle plus diffuse endocuticle, epicuticle plus lamellate endocuticle, or even multiple layers of cuticle. The ultrastructural evidence suggests that continuous incubation with β-ecdysone in plain medium does not always inhibit cuticle formationper se, but does prevent tanning of the partially formed cuticle.

Naked singularities in higher dimensional Vaidya space-times

International Nuclear Information System (INIS)

Ghosh, S. G.; Dadhich, Naresh

2001-01-01

We investigate the end state of the gravitational collapse of a null fluid in higher-dimensional space-times. Both naked singularities and black holes are shown to be developing as the final outcome of the collapse. The naked singularity spectrum in a collapsing Vaidya region (4D) gets covered with the increase in dimensions and hence higher dimensions favor a black hole in comparison to a naked singularity. The cosmic censorship conjecture will be fully respected for a space of infinite dimension

Dressing up a Kerr naked singularity

Energy Technology Data Exchange (ETDEWEB)

Calvani, M [Padua Univ. (Italy). Ist. di Astronomia; Nobili, L [Padua Univ. (Italy). Ist. di Fisica

1979-06-11

The evolution of a naked singularity surrounded by an accreting disk of matter is studied; two kinds of disks are considered: the standard thin-disk model and the thick barytropic model, for several initial conditions. It is shown that any Kerr naked singularity slows down in a finite time to a maximal Kerr black hole. The final mass, the luminosity and the time of evolution of the singularity are evaluated.

Chemical and structural analysis of Eucalyptus globulus and E. camaldulensis leaf cuticles: a lipidized cell wall region

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Paula eGuzmán

2014-09-01

Full Text Available The plant cuticle has traditionally been conceived as an independent hydrophobic layer that covers the external epidermal cell wall. Due to its complexity, the existing relationship between cuticle chemical composition and ultra-structure remains unclear to date. This study aimed to examine the link between chemical composition and structure of isolated, adaxial leaf cuticles of Eucalyptus camaldulensis and E. globulus by the gradual extraction and identification of lipid constituents (cutin and soluble lipids, coupled to spectroscopic and microscopic analyses. The soluble compounds and cutin monomers identified could not be assigned to a concrete internal cuticle ultra-structure. After cutin depolymerization, a cellulose network resembling the cell wall was observed, with different structural patterns in the regions ascribed to the cuticle proper and cuticular layer, respectively. Our results suggest that the current cuticle model should be revised, stressing the presence and major role of cell wall polysaccharides. It is concluded that the cuticle may be interpreted as a modified cell wall region which contains additional lipids. The major heterogeneity of the plant cuticle makes it difficult to establish a direct link between cuticle chemistry and structure with the existing methodologies.

Cuticle of 'Gala' and 'Galaxy' apples cultivars under different environmental conditions

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Magda Andréia Tessmer

2012-10-01

Full Text Available This study aimed to analyze the cuticle thickness and pattern of epicuticular wax deposition in 'Gala' and 'Galaxy' apple cultivars (Malus domestica Borkh, from three Brazilian producing areas: Vacaria (RS, Fraiburgo (SC and São Joaquim (SC with altitudes of 971, 1,048 and 1,353m, respectively. Harvested fruit were kept under two storage conditions: regular atmosphere (RA (0 ºC and 90% RH and controlled atmosphere (CA (1.5% O2, 2.5% CO2, 0ºC and 90% RH. Cuticle thickness measurements were made using LM and the deposition pattern of epicuticular wax observed with a SEM. Altitude among the apple producing areas was not a factor in deposition pattern of waxes between the cultivars but at higher altitudes, the cuticle was thicker in both the cultivars. In the freshly-harvested fruits, waxes deposition in the form of platelets and the mechanism of “tear and repair” were observed. Severity of microcracks in the cuticle was more evident on the fruits from CA.

Dehydration protection provided by a maternal cuticle improves offspring fitness in the moss Funaria hygrometrica.

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Budke, Jessica M; Goffinet, Bernard; Jones, Cynthia S

2013-05-01

In bryophytes the sporophyte offspring are in contact with, nourished from, and partially surrounded by the maternal gametophyte throughout their lifespan. During early development, the moss sporophyte is covered by the calyptra, a cap of maternal gametophyte tissue that has a multilayered cuticle. In this study the effects on sporophyte offspring fitness of removing the maternal calyptra cuticle, in combination with dehydration stress, is experimentally determined. Using the moss Funaria hygrometrica, calyptra cuticle waxes were removed by chemical extraction and individuals were exposed to a short-term dehydration event. Sporophytes were returned to high humidity to complete development and then aspects of sporophyte survival, development, functional morphology, and reproductive output were measured. It was found that removal of calyptra cuticle under low humidity results in significant negative impacts to moss sporophyte fitness, resulting in decreased survival, increased tissue damage, incomplete sporophyte development, more peristome malformations, and decreased reproductive output. This study represents the strongest evidence to date that the structure of the calyptra cuticle functions in dehydration protection of the immature moss sporophyte. The investment in a maternal calyptra with a multilayered cuticle increases offspring fitness and provides a functional explanation for calyptra retention across mosses. The moss calyptra may represent the earliest occurance of maternal protection via structural provisioning of a cuticle in green plants.

Absorption of UV-B to blue light radiation by leaf cuticles of selected crop plants

International Nuclear Information System (INIS)

Baur, P.; Stulle, K.; Schönherr, J.; Uhlig, B.

1998-01-01

Plants have protective pigments absorbing destructive shortwave radiation. These pigments have been found in the epidermis and mesophyll of leaves. We studied the absorption characteristics of the leaf cuticle, the outermost part of the epidermis that is directly exposed to radiation. Adaxial leaf cuticles of apple, pear, sour cherry, strawberry, cauliflower, sugarbeet, and 13 other plant species were tested. The UV-B absorption was highest in Citrus aurantium and Citrus maxima (<3 % transmittance) and lowest in sugarbeet and peach (>64 % transmittance). The absorption maxima are at wavelenghts below 320 nm. Significant absorption was also determined at 500 nm, which correlated with cuticle thickness of the plant species (r(2)=0.72). The absorption in the range of 250 to 350 nm is caused by pigments with a high extinction coefficient. This absorption is species dependent and the patterns were designated to three different types. The highest absorption was found in evergreen species. The extraction of cuticular waxes had little effect on absorption. The specific absorption of shortwave radiation by plant cuticles is probably caused by pigments covalently bound to cut in. It is known for some plant species that cuticles can contain the phenolics p-coumaric acid, ferulic acid, and vanillic acid. Mixtures of these phenolics had spectra similar to cuticles. For most species absorption of shortwave radiation by the cuticle alone does not give complete protection

Stress resistance in the naked mole-rat: the bare essentials - a mini-review.

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Lewis, Kaitlyn N; Mele, James; Hornsby, Peter J; Buffenstein, Rochelle

2012-01-01

Studies comparing similar-sized species with disparate longevity may elucidate novel mechanisms that abrogate aging and prolong good health. We focus on the longest living rodent, the naked mole-rat. This mouse-sized mammal lives ~8 times longer than do mice and, despite high levels of oxidative damage evident at a young age, it is not only very resistant to spontaneous neoplasia but also shows minimal decline in age-associated physiological traits. We assess the current status of stress resistance and longevity, focusing in particular on the molecular and cellular responses to cytotoxins and other stressors between the short-lived laboratory mouse and the naked mole-rat. Like other experimental animal models of lifespan extension, naked mole-rat fibroblasts are extremely tolerant of a broad spectrum of cytotoxins including heat, heavy metals, DNA-damaging agents and xenobiotics, showing LD(50) values between 2- and 20-fold greater than those of fibroblasts of shorter-lived mice. Our new data reveal that naked mole-rat fibroblasts stop proliferating even at low doses of toxin whereas those mouse fibroblasts that survive treatment rapidly re-enter the cell cycle and may proliferate with DNA damage. Naked mole-rat fibroblasts also show significantly higher constitutive levels of both p53 and Nrf2 protein levels and activity, and this increases even further in response to toxins. Enhanced cell signaling via p53 and Nrf2 protects cells against proliferating with damage, augments clearance of damaged proteins and organelles and facilitates the maintenance of both genomic and protein integrity. These pathways collectively regulate a myriad of mechanisms which may contribute to the attenuated aging profile and sustained healthspan of the naked mole-rat. Understanding how these are regulated may be also integral to sustaining positive human healthspan well into old age and may elucidate novel therapeutics for delaying the onset and progression of physiological declines

How does the nectar of stomata-free nectaries cross the cuticle?

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Elder Antônio Sousa Paiva

Full Text Available ABSTRACT In many glandular structures, departure from the cell is only one step in the process of exudate release to the plant surface. Here the set of events that lead nectar to the external environment is presented and discussed mainly for stomata-free nectaries. After being synthesized, the nectar or some of its component needs to be released to the environment where it performs its functions. Nectar precursors derived from cell metabolism need to cross several barriers, such as the cell membrane and cell wall, in order to become nectar. Then the nectar must cross the cuticle or pass through stomata in order to be offered to plant mutualists. Release through stomata is a simple mechanism, but the ways by which nectar crosses the cuticle is still controversial. Hydrophilic pathways in the cuticle and repetitive cycles of rupture or cuticle detachment are the main routes for nectar release in stomata-free nectaries. In addition to nectar, there are other exogenous secretions that must leave the protoplast and reach the plant surface to perform their function. The ways by which nectar is released discussed herein are likely relevant to understanding the release of other hydrophilic products of the secretory process of plants.

Intrathecal injection of naked plasmid DNA provides long-term expression of secreted proteins.

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Hughes, Travis S; Langer, Stephen J; Johnson, Kirk W; Chavez, Raymond A; Watkins, Linda R; Milligan, Erin D; Leinwand, Leslie A

2009-01-01

Therapeutic benefit has been reported to result from intrathecal (i.t.) injection of transgene vectors, including naked DNA. However, most studies using naked DNA have measured only the transgene expression of intracellular proteins. Here we demonstrate that i.t. injection of naked DNA can result in long-term expression of secreted proteins. Plasmids expressing either secreted alkaline phosphatase (SEAP) or human interleukin-10 (hIL-10) were injected into the i.t. space in rats, and transgene products were repeatedly measured in the cerebrospinal fluid (CSF). Both SEAP and hIL-10 were maximal at 1 and 2 days after the injection and still detectable at 4 months. The utilization of a plasmid having two features that are hypothesized to increase gene expression (matrix attachment regions (MARs) and lack of CpG dinucleotides) resulted in a significant increase in gene expression. Reinjection of SEAP or hIL-10 plasmids after 4 months significantly increased protein levels at 1 and 14 days after the reinjection. SEAP was uniformly distributed between the DNA delivery site (approximately vertebral level T13) and the lumbar puncture site (L5/L6 inter-vertebral space), was reduced at the cisterna magna, and was detectable, though at much lower levels, in serum. These data suggest that naked DNA has the potential to be used as a therapeutic tool for applications that require long-term release of transgenes into the CSF.

Transcriptome Analysis of Mango (Mangifera indica L.) Fruit Epidermal Peel to Identify Putative Cuticle-Associated Genes

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Tafolla-Arellano, Julio C.; Zheng, Yi; Sun, Honghe; Jiao, Chen; Ruiz-May, Eliel; Hernández-Oñate, Miguel A.; González-León, Alberto; Báez-Sañudo, Reginaldo; Fei, Zhangjun; Domozych, David; Rose, Jocelyn K. C.; Tiznado-Hernández, Martín E.

2017-04-01

Mango fruit (Mangifera indica L.) are highly perishable and have a limited shelf life, due to postharvest desiccation and senescence, which limits their global distribution. Recent studies of tomato fruit suggest that these traits are influenced by the expression of genes that are associated with cuticle metabolism. However, studies of these phenomena in mango fruit are limited by the lack of genome-scale data. In order to gain insight into the mango cuticle biogenesis and identify putative cuticle-associated genes, we analyzed the transcriptomes of peels from ripe and overripe mango fruit using RNA-Seq. Approximately 400 million reads were generated and de novo assembled into 107,744 unigenes, with a mean length of 1,717 bp and with this information an online Mango RNA-Seq Database (http://bioinfo.bti.cornell.edu/cgi-bin/mango/index.cgi) which is a valuable genomic resource for molecular research into the biology of mango fruit was created. RNA-Seq analysis suggested that the pathway leading to biosynthesis of the cuticle component, cutin, is up-regulated during overripening. This data was supported by analysis of the expression of several putative cuticle-associated genes and by gravimetric and microscopic studies of cuticle deposition, revealing a complex continuous pattern of cuticle deposition during fruit development and involving substantial accumulation during ripening/overripening.

Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities

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Stuchlík, Z.; Pugliese, D.; Schee, J.; Kučáková, H.

2015-09-01

We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Hořava quantum gravity, characterized by a dimensionless parameter ω M^2, combining the gravitational mass parameter M of the spacetime with the Hořava parameter ω reflecting the role of the quantum corrections. In dependence on the value of ω M^2, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an "antigravity" sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l= const. In the K-S naked singularity spacetimes with ω M^2 > 0.2811, doubled tori with the same l= const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ω M^2 < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics.

Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities

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Stuchlik, Z.; Pugliese, D.; Schee, J.; Kucakova, H. [Silesian University in Opava, Faculty of Philosophy and Science, Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Opava (Czech Republic)

2015-09-15

We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Horava quantum gravity, characterized by a dimensionless parameter ωM{sup 2}, combining the gravitational mass parameter M of the spacetime with the Horava parameter ω, reflecting the role of the quantum corrections. In dependence on the value of ωM{sup 2}, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an @gantigravity@h sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l = const. In the K-S naked singularity spacetimes with ωM{sup 2} > 0.2811, doubled tori with the same l = const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ωM{sup 2} < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics. (orig.)

Stress Resistance in the Naked Mole-Rat: The Bare Essentials – A Mini-Review

Science.gov (United States)

Lewis, Kaitlyn N.; Mele, James; Hornsby, Peter J.; Buffenstein, Rochelle

2012-01-01

Background Studies comparing similar-sized species with disparate longevity may elucidate novel mechanisms that abrogate aging and prolong good health. We focus on the longest living rodent, the naked mole-rat. This mouse-sized mammal lives ∼8 times longer than do mice and, despite high levels of oxidative damage evident at a young age, it is not only very resistant to spontaneous neoplasia but also shows minimal decline in age-associated physiological traits. Objectives We assess the current status of stress resistance and longevity, focusing in particular on the molecular and cellular responses to cytotoxins and other stressors between the short-lived laboratory mouse and the naked mole-rat. Results Like other experimental animal models of lifespan extension, naked mole-rat fibroblasts are extremely tolerant of a broad spectrum of cytotoxins including heat, heavy metals, DNA-damaging agents and xenobiotics, showing LD50 values between 2- and 20-fold greater than those of fibroblasts of shorter-lived mice. Our new data reveal that naked mole-rat fibroblasts stop proliferating even at low doses of toxin whereas those mouse fibroblasts that survive treatment rapidly re-enter the cell cycle and may proliferate with DNA damage. Naked mole-rat fibroblasts also show significantly higher constitutive levels of both p53 and Nrf2 protein levels and activity, and this increases even further in response to toxins. Conclusion Enhanced cell signaling via p53 and Nrf2 protects cells against proliferating with damage, augments clearance of damaged proteins and organelles and facilitates the maintenance of both genomic and protein integrity. These pathways collectively regulate a myriad of mechanisms which may contribute to the attenuated aging profile and sustained healthspan of the naked mole-rat. Understanding how these are regulated may be also integral to sustaining positive human healthspan well into old age and may elucidate novel therapeutics for delaying the onset and

Naked singularities in self-similar spherical gravitational collapse

International Nuclear Information System (INIS)

Ori, A.; Piran, T.

1987-01-01

We present general-relativistic solutions of self-similar spherical collapse of an adiabatic perfect fluid. We show that if the equation of state is soft enough (Γ-1<<1), a naked singularity forms. The singularity resembles the shell-focusing naked singularities that arise in dust collapse. This solution increases significantly the range of matter fields that should be ruled out in order that the cosmic-censorship hypothesis will hold

Selective inflammatory pain insensitivity in the African naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Park, Thomas J; Lu, Ying; Jüttner, René; Smith, Ewan St J; Hu, Jing; Brand, Antje; Wetzel, Christiane; Milenkovic, Nevena; Erdmann, Bettina; Heppenstall, Paul A; Laurito, Charles E; Wilson, Steven P; Lewin, Gary R

2008-01-01

In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P) in cutaneous sensory fibers. Naked mole-rats show a unique and remarkable lack of pain-related behaviors to two potent algogens, acid and capsaicin. Furthermore, when exposed to inflammatory insults or known mediators, naked mole-rats do not display thermal hyperalgesia. In contrast, naked mole-rats do display nocifensive behaviors in the formalin test and show mechanical hyperalgesia after inflammation. Using electrophysiology, we showed that primary afferent nociceptors in naked mole-rats are insensitive to acid stimuli, consistent with the animal's lack of acid-induced behavior. Acid transduction by sensory neurons is observed in birds, amphibians, and fish, which suggests that this tranduction mechanism has been selectively disabled in the naked mole-rat in the course of its evolution. In contrast, nociceptors do respond vigorously to capsaicin, and we also show that sensory neurons express a transient receptor potential vanilloid channel-1 ion channel that is capsaicin sensitive. Nevertheless, the activation of capsaicin-sensitive sensory neurons in naked mole-rats does not produce pain-related behavior. We show that capsaicin-sensitive nociceptors in the naked mole-rat are functionally connected to superficial dorsal horn neurons as in mice. However, the same nociceptors are also functionally connected to deep dorsal horn neurons, a connectivity that is rare in mice. The pain biology of the naked mole-rat is unique among mammals, thus the study of pain mechanisms in this unusual species can provide major insights into what constitutes "normal" mammalian nociception.

Selective inflammatory pain insensitivity in the African naked mole-rat (Heterocephalus glaber.

Directory of Open Access Journals (Sweden)

Thomas J Park

2008-01-01

Full Text Available In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P in cutaneous sensory fibers. Naked mole-rats show a unique and remarkable lack of pain-related behaviors to two potent algogens, acid and capsaicin. Furthermore, when exposed to inflammatory insults or known mediators, naked mole-rats do not display thermal hyperalgesia. In contrast, naked mole-rats do display nocifensive behaviors in the formalin test and show mechanical hyperalgesia after inflammation. Using electrophysiology, we showed that primary afferent nociceptors in naked mole-rats are insensitive to acid stimuli, consistent with the animal's lack of acid-induced behavior. Acid transduction by sensory neurons is observed in birds, amphibians, and fish, which suggests that this tranduction mechanism has been selectively disabled in the naked mole-rat in the course of its evolution. In contrast, nociceptors do respond vigorously to capsaicin, and we also show that sensory neurons express a transient receptor potential vanilloid channel-1 ion channel that is capsaicin sensitive. Nevertheless, the activation of capsaicin-sensitive sensory neurons in naked mole-rats does not produce pain-related behavior. We show that capsaicin-sensitive nociceptors in the naked mole-rat are functionally connected to superficial dorsal horn neurons as in mice. However, the same nociceptors are also functionally connected to deep dorsal horn neurons, a connectivity that is rare in mice. The pain biology of the naked mole-rat is unique among mammals, thus the study of pain mechanisms in this unusual species can provide major insights into what constitutes "normal" mammalian nociception.

Fruit cuticle lipid composition and water loss in a diverse collection of pepper (capsicum)

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Pepper (Capsicum spp.) fruits are covered by a relatively thick coating of cuticle that limits fruit water loss, a trait previously associated with maintenance of post-harvest fruit quality during commercial marketing. We’ve examined the fruit cuticles from 50 diverse pepper genotypes from a world c...

Nonlinear Porous Diffusion Modeling of Hydrophilic Ionic Agrochemicals in Astomatous Plant Cuticle Aqueous Pores: A Mechanistic Approach.

Science.gov (United States)

Tredenick, Eloise C; Farrell, Troy W; Forster, W Alison; Psaltis, Steven T P

2017-01-01

The agricultural industry requires improved efficacy of sprays being applied to crops and weeds in order to reduce their environmental impact and deliver improved financial returns. Enhanced foliar uptake is one means of improving efficacy. The plant leaf cuticle is known to be the main barrier to diffusion of agrochemicals within the leaf. The usefulness of a mathematical model to simulate uptake of agrochemicals in plant cuticles has been noted previously in the literature, as the results of each uptake experiment are specific to each formulation of active ingredient, plant species and environmental conditions. In this work we develop a mathematical model and numerical simulation for the uptake of hydrophilic ionic agrochemicals through aqueous pores in plant cuticles. We propose a novel, nonlinear, porous diffusion model for ionic agrochemicals in isolated cuticles, which extends simple diffusion through the incorporation of parameters capable of simulating: plant species variations, evaporation of surface droplet solutions, ion binding effects on the cuticle surface and swelling of the aqueous pores with water. We validate our theoretical results against appropriate experimental data, discuss the key sensitivities in the model and relate theoretical predictions to appropriate physical mechanisms. Major influencing factors have been found to be cuticle structure, including tortuosity and density of the aqueous pores, and to a lesser extent humidity and cuticle surface ion binding effects.

Nonlinear Porous Diffusion Modeling of Hydrophilic Ionic Agrochemicals in Astomatous Plant Cuticle Aqueous Pores: A Mechanistic Approach

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Eloise C. Tredenick

2017-05-01

Full Text Available The agricultural industry requires improved efficacy of sprays being applied to crops and weeds in order to reduce their environmental impact and deliver improved financial returns. Enhanced foliar uptake is one means of improving efficacy. The plant leaf cuticle is known to be the main barrier to diffusion of agrochemicals within the leaf. The usefulness of a mathematical model to simulate uptake of agrochemicals in plant cuticles has been noted previously in the literature, as the results of each uptake experiment are specific to each formulation of active ingredient, plant species and environmental conditions. In this work we develop a mathematical model and numerical simulation for the uptake of hydrophilic ionic agrochemicals through aqueous pores in plant cuticles. We propose a novel, nonlinear, porous diffusion model for ionic agrochemicals in isolated cuticles, which extends simple diffusion through the incorporation of parameters capable of simulating: plant species variations, evaporation of surface droplet solutions, ion binding effects on the cuticle surface and swelling of the aqueous pores with water. We validate our theoretical results against appropriate experimental data, discuss the key sensitivities in the model and relate theoretical predictions to appropriate physical mechanisms. Major influencing factors have been found to be cuticle structure, including tortuosity and density of the aqueous pores, and to a lesser extent humidity and cuticle surface ion binding effects.

In vivo silencing of alpha-synuclein using naked siRNA

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Charisse Klaus

2008-11-01

Full Text Available Abstract Background Overexpression of α-synuclein (SNCA in families with multiplication mutations causes parkinsonism and subsequent dementia, characterized by diffuse Lewy Body disease post-mortem. Genetic variability in SNCA contributes to risk of idiopathic Parkinson's disease (PD, possibly as a result of overexpression. SNCA downregulation is therefore a valid therapeutic target for PD. Results We have identified human and murine-specific siRNA molecules which reduce SNCA in vitro. As a proof of concept, we demonstrate that direct infusion of chemically modified (naked, murine-specific siRNA into the hippocampus significantly reduces SNCA levels. Reduction of SNCA in the hippocampus and cortex persists for a minimum of 1 week post-infusion with recovery nearing control levels by 3 weeks post-infusion. Conclusion We have developed naked gene-specific siRNAs that silence expression of SNCA in vivo. This approach may prove beneficial toward our understanding of the endogenous functional equilibrium of SNCA, its role in disease, and eventually as a therapeutic strategy for α-synucleinopathies resulting from SNCA overexpression.

In vivo silencing of alpha-synuclein using naked siRNA

Science.gov (United States)

Lewis, Jada; Melrose, Heather; Bumcrot, David; Hope, Andrew; Zehr, Cynthia; Lincoln, Sarah; Braithwaite, Adam; He, Zhen; Ogholikhan, Sina; Hinkle, Kelly; Kent, Caroline; Toudjarska, Ivanka; Charisse, Klaus; Braich, Ravi; Pandey, Rajendra K; Heckman, Michael; Maraganore, Demetrius M; Crook, Julia; Farrer, Matthew J

2008-01-01

Background Overexpression of α-synuclein (SNCA) in families with multiplication mutations causes parkinsonism and subsequent dementia, characterized by diffuse Lewy Body disease post-mortem. Genetic variability in SNCA contributes to risk of idiopathic Parkinson's disease (PD), possibly as a result of overexpression. SNCA downregulation is therefore a valid therapeutic target for PD. Results We have identified human and murine-specific siRNA molecules which reduce SNCA in vitro. As a proof of concept, we demonstrate that direct infusion of chemically modified (naked), murine-specific siRNA into the hippocampus significantly reduces SNCA levels. Reduction of SNCA in the hippocampus and cortex persists for a minimum of 1 week post-infusion with recovery nearing control levels by 3 weeks post-infusion. Conclusion We have developed naked gene-specific siRNAs that silence expression of SNCA in vivo. This approach may prove beneficial toward our understanding of the endogenous functional equilibrium of SNCA, its role in disease, and eventually as a therapeutic strategy for α-synucleinopathies resulting from SNCA overexpression. PMID:18976489

The naked mole-rat exhibits an unusual cardiac myofilament protein profile providing new insights into heart function of this naturally subterranean rodent.

Science.gov (United States)

Grimes, Kelly M; Barefield, David Y; Kumar, Mohit; McNamara, James W; Weintraub, Susan T; de Tombe, Pieter P; Sadayappan, Sakthivel; Buffenstein, Rochelle

2017-12-01

The long-lived, hypoxic-tolerant naked mole-rat well-maintains cardiac function over its three-decade-long lifespan and exhibits many cardiac features atypical of similar-sized laboratory rodents. For example, they exhibit low heart rates and resting cardiac contractility, yet have a large cardiac reserve. These traits are considered ecophysiological adaptations to their dank subterranean atmosphere of low oxygen and high carbon dioxide levels and may also contribute to negligible declines in cardiac function during aging. We asked if naked mole-rats had a different myofilament protein signature to that of similar-sized mice that commonly show both high heart rates and high basal cardiac contractility. Adult mouse ventricles predominantly expressed α-myosin heavy chain (97.9 ± 0.4%). In contrast, and more in keeping with humans, β myosin heavy chain was the dominant isoform (79.0 ± 2.0%) in naked mole-rat ventricles. Naked mole-rat ventricles diverged from those of both humans and mice, as they expressed both cardiac and slow skeletal isoforms of troponin I. This myofilament protein profile is more commonly observed in mice in utero and during cardiomyopathies. There were no species differences in phosphorylation of cardiac myosin binding protein-C or troponin I. Phosphorylation of both ventricular myosin light chain 2 and cardiac troponin T in naked mole-rats was approximately half that observed in mice. Myofilament function was also compared between the two species using permeabilized cardiomyocytes. Together, these data suggest a cardiac myofilament protein signature that may contribute to the naked mole-rat's suite of adaptations to its natural subterranean habitat.

High molecular weight hyaluronan mediates the cancer resistance of the naked mole-rat

OpenAIRE

Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

2013-01-01

The naked mole-rat displays exceptional longevity, with a maximum lifespan exceeding 30 years 1–3 . This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole-rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years 4,5 . In addition to their longevity, naked mole-rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single inci...

A cytosolic protein factor from the naked mole-rat activates proteasomes of other species and protects these from inhibition

Science.gov (United States)

Rodriguez, Karl A.; Osmulski, Pawel A.; Pierce, Anson; Weintraub, Susan T.; Gaczynska, Maria; Buffenstein, Rochelle

2015-01-01

The naked mole-rat maintains robust proteostasis and high levels of proteasome-mediated proteolysis for most of its exceptional (~31y) life span. Here, we report that the highly active proteasome from the naked mole-rat liver resists attenuation by a diverse suite of proteasome-specific small molecule inhibitors. Moreover, mouse, human, and yeast proteasomes exposed to the proteasome-depleted, naked mole-rat cytosolic fractions, recapitulate the observed inhibition resistance, and mammalian proteasomes also show increased activity. Gel filtration coupled with mass spectrometry and atomic force microscopy indicates that these traits are supported by a protein factor that resides in the cytosol. This factor interacts with the proteasome and modulates its activity. Although HSP72 and HSP40 (Hdj1) are among the constituents of this factor, the observed phenomenon, such as increasing peptidase activity and protecting against inhibition cannot be reconciled with any known chaperone functions. This novel function may contribute to the exceptional protein homeostasis in the naked mole-rat and allow it to successfully defy aging. PMID:25018089

Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

Science.gov (United States)

Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Keefe, D.

2009-01-01

Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the "coalified layer" with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: "vitrinite (mesophyll) + cuticle (biomacropolymer) = compression". Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. ?? 2009 Elsevier B.V. All rights reserved.

Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia (Canada); D' Angelo, Jose A. [Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Area de Quimica, Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Centro Universitario - M5502JMA - Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, Bloomington, IN 47405-2208 (United States); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

2009-08-01

Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the ''coalified layer'' with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: ''vitrinite (mesophyll) + cuticle (biomacropolymer) = compression''. Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. (author)

Agronomic performance of naked oat (Avena nuda L. and faba bean intercropping

Directory of Open Access Journals (Sweden)

Agnieszka Klimek-Kopyra

2015-06-01

Full Text Available The most common cereals for faba bean (Vicia faba L. used in intercrops is conventional oat (Avena sativa L. An alternative to oat may be naked oat (Avena nuda L., whose oil content and quality is double. Here, intercropping of naked oat with two different faba bean cultivars (determinate-high tannin and indeterminate-low tannin was compared with sole crops of each species in 2006-2008. The treatments were: sole naked oat at 500 kernels m², indeterminate sole faba bean at 50 seeds m², determinate sole faba bean at 70 seeds m², and an additive series of 25%, 50%, and 75% of faba bean seeding rate mixed with the naked oat seeding rate. Our results demonstrated that intercropping increased the Land Equivalent Ratio by +3% to +9% over sole cropping. Raising the faba bean seeding rate in a mixture from 25% to 75% reduced oat grain yield from 630 (determinate cultivar to 760 kg ha-1 (indeterminate cultivar but increased faba bean grain yield from 760 kg ha-1. Higher yield and leaf area index (LAI and photosynthetically active radiation (PAR values show that the indeterminate cultivar of faba bean is more suitable in mixture with naked oat. The high value of competition index (CR > 1 indicates domination and aggressiveness of faba bean towards naked oat. Regardless of cultivar type, mixture of faba bean with naked oat is less productive than pure sowing.

Genome sequencing reveals insights into physiology and longevity of the naked mole rat

DEFF Research Database (Denmark)

Kim, Eun Bae; Fang, Xiaodong; Fushan, Alexey A

2011-01-01

The naked mole rat (Heterocephalus glaber) is a strictly subterranean, extraordinarily long-lived eusocial mammal. Although it is the size of a mouse, its maximum lifespan exceeds 30 years, making this animal the longest-living rodent. Naked mole rats show negligible senescence, no age......-related increase in mortality, and high fecundity until death. In addition to delayed ageing, they are resistant to both spontaneous cancer and experimentally induced tumorigenesis. Naked mole rats pose a challenge to the theories that link ageing, cancer and redox homeostasis. Although characterized...... by significant oxidative stress, the naked mole rat proteome does not show age-related susceptibility to oxidative damage or increased ubiquitination. Naked mole rats naturally reside in large colonies with a single breeding female, the 'queen', who suppresses the sexual maturity of her subordinates. They also...

Blunted neuronal calcium response to hypoxia in naked mole-rat hippocampus.

Directory of Open Access Journals (Sweden)

Bethany L Peterson

Full Text Available Naked mole-rats are highly social and strictly subterranean rodents that live in large communal colonies in sealed and chronically oxygen-depleted burrows. Brain slices from naked mole-rats show extreme tolerance to hypoxia compared to slices from other mammals, as indicated by maintenance of synaptic transmission under more hypoxic conditions and three fold longer latency to anoxic depolarization. A key factor in determining whether or not the cellular response to hypoxia is reversible or leads to cell death may be the elevation of intracellular calcium concentration. In the present study, we used fluorescent imaging techniques to measure relative intracellular calcium changes in CA1 pyramidal cells of hippocampal slices during hypoxia. We found that calcium accumulation during hypoxia was significantly and substantially attenuated in slices from naked mole-rats compared to slices from laboratory mice. This was the case for both neonatal (postnatal day 6 and older (postnatal day 20 age groups. Furthermore, while both species demonstrated more calcium accumulation at older ages, the older naked mole-rats showed a smaller calcium accumulation response than even the younger mice. A blunted intracellular calcium response to hypoxia may contribute to the extreme hypoxia tolerance of naked mole-rat neurons. The results are discussed in terms of a general hypothesis that a very prolonged or arrested developmental process may allow adult naked mole-rat brain to retain the hypoxia tolerance normally only seen in neonatal mammals.

Blunted neuronal calcium response to hypoxia in naked mole-rat hippocampus.

Science.gov (United States)

Peterson, Bethany L; Larson, John; Buffenstein, Rochelle; Park, Thomas J; Fall, Christopher P

2012-01-01

Naked mole-rats are highly social and strictly subterranean rodents that live in large communal colonies in sealed and chronically oxygen-depleted burrows. Brain slices from naked mole-rats show extreme tolerance to hypoxia compared to slices from other mammals, as indicated by maintenance of synaptic transmission under more hypoxic conditions and three fold longer latency to anoxic depolarization. A key factor in determining whether or not the cellular response to hypoxia is reversible or leads to cell death may be the elevation of intracellular calcium concentration. In the present study, we used fluorescent imaging techniques to measure relative intracellular calcium changes in CA1 pyramidal cells of hippocampal slices during hypoxia. We found that calcium accumulation during hypoxia was significantly and substantially attenuated in slices from naked mole-rats compared to slices from laboratory mice. This was the case for both neonatal (postnatal day 6) and older (postnatal day 20) age groups. Furthermore, while both species demonstrated more calcium accumulation at older ages, the older naked mole-rats showed a smaller calcium accumulation response than even the younger mice. A blunted intracellular calcium response to hypoxia may contribute to the extreme hypoxia tolerance of naked mole-rat neurons. The results are discussed in terms of a general hypothesis that a very prolonged or arrested developmental process may allow adult naked mole-rat brain to retain the hypoxia tolerance normally only seen in neonatal mammals.

Cuticles of European and American lobsters harbor diverse bacterial species and differ in disease susceptibility.

Science.gov (United States)

Whitten, Miranda M A; Davies, Charlotte E; Kim, Anita; Tlusty, Michael; Wootton, Emma C; Chistoserdov, Andrei; Rowley, Andrew F

2014-06-01

Diseases of lobster shells have a significant impact on fishing industries but the risk of disease transmission between different lobster species has yet to be properly investigated. This study compared bacterial biofilm communities from American (Homarus americanus) and European lobsters (H. gammarus), to assess both healthy cuticle and diseased cuticle during lesion formation. Culture-independent molecular techniques revealed diversity in the bacterial communities of cuticle biofilms both within and between the two lobster species, and identified three bacterial genera associated with shell lesions plus two putative beneficial bacterial species (detected exclusively in healthy cuticle or healing damaged cuticle). In an experimental aquarium shared between American and European lobsters, heterospecific transmission of potentially pathogenic bacteria appeared to be very limited; however, the claws of European lobsters were more likely to develop lesions when reared in the presence of American lobsters. Aquarium biofilms were also examined but revealed no candidate pathogens for environmental transmission. Aquimarina sp. 'homaria' (a potential pathogen associated with a severe epizootic form of shell disease) was detected at a much higher prevalence among American than European lobsters, but its presence correlated more with exacerbation of existing lesions rather than with lesion initiation. © 2014 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Cuticle hydrocarbons in saline aquatic beetles

Directory of Open Access Journals (Sweden)

María Botella-Cruz

2017-07-01

Full Text Available Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae and Enochrus jesusarribasi (Hydrophilidae, using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae compared with other aquatic Coleoptera (freshwater Dytiscidae. Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desiccation. The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species.

Naked singularities and cosmic censorship: comment on the current situation

International Nuclear Information System (INIS)

Seifert, H.J.

1979-01-01

The current discussion is mainly concerned with how, or indeed, whether space-times possessing naked singularities can be ruled out as being too unrealistic or not being singular at all. The present position is summarized, with references, under the following headings: the Hawking-Penrose existence theorems, hydrodynamical singularities and the strength of naked singularities. (UK)

Extreme hypoxia tolerance of naked mole-rat brain.

Science.gov (United States)

Larson, John; Park, Thomas J

2009-12-09

Mammalian brains have extremely high levels of aerobic metabolism and typically suffer irreversible damage after brief periods of oxygen deprivation such as occur during stroke or cardiac arrest. Here we report that brain tissue from naked mole-rats, rodents that live in a chronically low-oxygen environment, is remarkably resistant to hypoxia: naked mole-rat neurons maintain synaptic transmission much longer than mouse neurons and can recover from periods of anoxia exceeding 30 min. We suggest that brain tolerance to hypoxia may result from slowed or arrested brain development in these extremely long-lived animals.

Proteomic analysis of chicken eggshell cuticle membrane layer

Czech Academy of Sciences Publication Activity Database

Mikšík, Ivan; Ergang, Peter; Pácha, Jiří

2014-01-01

Roč. 406, č. 29 (2014), s. 7633-7640 ISSN 1618-2642 R&D Projects: GA ČR(CZ) GA13-17224S Institutional support: RVO:67985823 Keywords : mass spectrometry * bioanalyticalmethods * cuticle * chicken proteins * insoluble proteins * eggshell Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.436, year: 2014

Ultrastructure, development, and homology of insect embryonic cuticles

Czech Academy of Sciences Publication Activity Database

Konopová, Barbora; Zrzavý, Jan

2005-01-01

Roč. 264, č. 3 (2005), s. 339-362 ISSN 0362-2525 R&D Projects: GA ČR(CZ) GD206/03/H034 Institutional research plan: CEZ:AV0Z50070508 Keywords : embryonic development * cuticle * metamorphosis Subject RIV: EA - Cell Biology Impact factor: 1.421, year: 2005

Mechanical properties of the cuticles of three cockroach species that differ in their wind-evoked escape behavior

Directory of Open Access Journals (Sweden)

Andrew J. Clark

2014-07-01

Full Text Available The structural and material properties of insect cuticle remain largely unexplored, even though they comprise the majority (approximately 80% of animals. Insect cuticle serves many functions, including protection against predatory attacks, which is especially beneficial to species failing to employ effective running escape responses. Despite recent advances in our understanding of insect escape behaviors and the biomechanics of insect cuticle, there are limited studies on the protective qualities of cuticle to extreme mechanical stresses and strains imposed by predatory attacks, and how these qualities vary between species employing different escape responses. Blattarians (cockroaches provide an appropriate model system for such studies. Wind-evoked running escape responses are strong in Periplaneta americana, weak in Blaberus craniifer and absent in Gromphodorhina portentosa, putting the latter two species at greater risk of being struck by a predator. We hypothesized that the exoskeletons in these two larger species could provide more protection from predatory strikes relative to the exoskeleton of P. americana. We quantified the protective qualities of the exoskeletons by measuring the puncture resistance, tensile strength, strain energy storage, and peak strain in fresh samples of thoracic and abdominal cuticles from these three species. We found a continuum in puncture resistance, tensile strength, and strain energy storage between the three species, which were greatest in G. portentosa, moderate in B. craniifer, and smallest in P. americana. Histological measurements of total cuticle thickness followed this same pattern. However, peak strain followed a different trend between species. The comparisons in the material properties drawn between the cuticles of G. portentosa, B. craniifer, and P. americana demonstrate parallels between cuticular biomechanics and predator running escape responses.

Naked-Eye Detection of Glucose in Saliva with Bienzymatic Paper-Based Sensor

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Luis A. Santana-Jiménez

2018-04-01

Full Text Available The high incidence of Diabetes Mellitus in low-income regions has promoted the development of low-cost alternatives to replace blood-based procedures. In this work, we present a bienzymatic paper-based sensor suitable for the naked-eye detection of glucose in saliva samples. The sensor was obtained by a stamping procedure and modified with chitosan to improve the colorimetric readout. The bienzymatic reaction of GOx-HRP coupled with 2,4,6-tribromo-3-hydroxy benzoic acid was applied for the detection of glucose within a range from 0 to 180 mgdL−1 in buffer and artificial saliva solutions. The visual readout was perceived by the naked eye and registered with an office scanner to evaluate the analytical performance. The results showed a limit of detection of 0.37 mgdL−1 (S/N = 3 with an R.S.D. of 1.69% and a linear range from 1 to 22.5 mgdL−1 with an R2 of 0.99235. The analysis of human saliva samples was performed without pre-processing, achieving recoveries from 92 to 114%. The naked-eye detection was evaluated under two different light settings, showing average recoveries of 108.58 and 90.65% for standard and low illumination. The proposed device showed potential for easy-to-use, sensitive, low-cost, fast, and device-free detection of salivary glucose suitable for untrained personnel operation and limited facilities.

Herbicide effects on cuticle ultrastructure in Eleusine indica and Portulaca oleracea.

Science.gov (United States)

Malpassi, Rosana N

2006-04-01

Eleusine indica and Portulaca oleracea are two common weeds in peanut crops in southern Córdoba. Two chemicals are frequently used to control them, quizalofop for grasses and lactofen for dicots. The objective is to study the effects of quizalofop and lactofen on cuticle ultrastructure in E. indica and P. oleracea, respectively. In the lab, quizalofop was applied on E. indica and lactofen on P. oleracea. Three plant categories were analyzed in each species: 3, 1-2, and no tiller in E. indica, and 8, 6, and 2 nomophylls in P. oleracea. Leaf samples from both species were collected at 7 and 16 days post-application and were treated for scanning electron microscopy. E. indica cuticle treated with lethal dose shows areas where epicuticular waxes disappear, specially in the youngest individuals. These areas are located predominantly on periclinal walls of typical epidermic cells and subsidiary cells. On the other hand, P. oleracea shows cuticle discontinuities that may be caused by lactofen entry. They are smaller and less frequent in plants having 8 or more nomophylls. The remaining waxes act as a herbicide accumulation compartment and, therefore, would partially prevent the active ingredient entry to epidermic cells.

Cuticle ultrastructure, cuticular lipid composition, and gene expression in hypoxia-stressed Arabidopsis stems and leaves.

Science.gov (United States)

Kim, Hyojin; Choi, Dongsu; Suh, Mi Chung

2017-06-01

An increased permeability of the cuticle is closely associated with downregulation of genes involved in cuticular lipid synthesis in hypoxia-stressed Arabidopsis and may allow plants to cope with oxygen deficiency. The hydrophobic cuticle layer consisting of cutin polyester and cuticular wax is the first barrier to protect the aerial parts of land plants from environmental stresses. In the present study, we investigated the role of cuticle membrane in Arabidopsis responses to oxygen deficiency. TEM analysis showed that the epidermal cells of hypoxia-treated Arabidopsis stems and leaves possessed a thinner electron-translucent cuticle proper and a more electron-dense cuticular layer. A reduction in epicuticular wax crystal deposition was observed in SEM images of hypoxia-treated Arabidopsis stem compared with normoxic control. Cuticular transpiration was more rapid in hypoxia-stressed leaves than in normoxic control. Total wax and cutin loads decreased by approximately 6-12 and 12-22%, respectively, and the levels of C29 alkanes, secondary alcohols, and ketones, C16:0 ω-hydroxy fatty acids, and C18:2 dicarboxylic acids were also prominently reduced in hypoxia-stressed Arabidopsis leaves and/or stems relative to normoxic control. Genome-wide transcriptome and quantitative RT-PCR analyses revealed that the expression of several genes involved in the biosynthesis and transport of cuticular waxes and cutin monomers were downregulated more than fourfold, but no significant alterations were detected in the transcript levels of fatty acid biosynthetic genes, BCCP2, PDH-E1α, and ENR1 in hypoxia-treated Arabidopsis stems and leaves compared with normoxic control. Taken together, an increased permeability of the cuticle is closely associated with downregulation of genes involved in cuticular lipid synthesis in hypoxia-stressed Arabidopsis. The present study elucidates one of the cuticle-related adaptive responses that may allow plants to cope with low oxygen levels.

Central visual system of the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Crish, Samuel D; Dengler-Crish, Christine M; Catania, Kenneth C

2006-02-01

Naked mole-rats are fossorial rodents native to eastern Africa that spend their lives in extensive subterranean burrows where visual cues are poor. Not surprisingly, they have a degenerated eye and optic nerve, suggesting they have poor visual abilities. However, little is known about their central visual system. To investigate the organization of their central visual system, we injected a neuronal tracer into the eyes of naked mole-rats and mice to compare the neural structures mediating vision. We found that the superior colliculus and lateral geniculate nucleus were severely atrophied in the naked mole-rat. The olivary pretectal nucleus was reduced but still retained its characteristic morphology, possibly indicating a role in light detection. In addition, the suprachiasmatic nucleus is well innervated and resembles the same structure in other rodents. The naked mole-rat appears to have selectively lost structures that mediate form vision while retaining structures needed for minimal entrainment of circadian rhythms. Similar results have been reported for other mole-rat species. Taken together, these data suggest that light detection may still play an important role in the lives of these "blind" animals: most likely for circadian entrainment or setting seasonal rhythms.

The naked mole-rat response to oxidative stress: just deal with it.

Science.gov (United States)

Lewis, Kaitlyn N; Andziak, Blazej; Yang, Ting; Buffenstein, Rochelle

2013-10-20

The oxidative stress theory of aging has been the most widely accepted theory of aging providing insights into why we age and die for over 50 years, despite mounting evidence from a multitude of species indicating that there is no direct relationship between reactive oxygen species (ROS) and longevity. Here we explore how different species, including the longest lived rodent, the naked mole-rat, have defied the most predominant aging theory. In the case of extremely long-lived naked mole-rat, levels of ROS production are found to be similar to mice, antioxidant defenses unexceptional, and even under constitutive conditions, naked mole-rats combine a pro-oxidant intracellular milieu with high, steady state levels of oxidative damage. Clearly, naked mole-rats can tolerate this level of oxidative stress and must have mechanisms in place to prevent its translation into potentially lethal diseases. In addition to the naked mole-rat, other species from across the phylogenetic spectrum and even certain mouse strains do not support this theory. Moreover, overexpressing or knocking down antioxidant levels alters levels of oxidative damage and even cancer incidence, but does not modulate lifespan. Perhaps, it is not oxidative stress that modulates healthspan and longevity, but other cytoprotective mechanisms that allow animals to deal with high levels of oxidative damage and stress, and nevertheless live long, relatively healthy lifespans. Studying these mechanisms in uniquely long-lived species, like the naked mole-rat, may help us tease out the key contributors to aging and longevity.

The extensible alloscutal cuticle of the tick, Ixodes ricinus

DEFF Research Database (Denmark)

Andersen, Svend Olav; Roepstorff, Peter

2005-01-01

The proteins in the distensible alloscutal cuticle of the blood-feeding tick, Ixodes ricinus, have been characterized by electrophoresis and chromatography, two of the proteins were purified and their total amino acid sequence determined. They show sequence similarity to cuticular proteins from t...

Naked singularity formation in Brans-Dicke theory

Energy Technology Data Exchange (ETDEWEB)

Ziaie, Amir Hadi; Atazadeh, Khedmat [Department of Physics, Shahid Beheshti University, Evin, Tehran 19839 (Iran, Islamic Republic of); Tavakoli, Yaser, E-mail: am.ziaie@mail.sbu.ac.i, E-mail: k-atazadeh@sbu.ac.i, E-mail: tavakoli@ubi.p [Departamento de Fisica, Universidade da Beira Interior, Rua Marques d' Avila e Bolama, 6200 Covilha (Portugal)

2010-04-07

Gravitational collapse of the Brans-Dicke scalar field with non-zero potential in the presence of matter fluid obeying the barotropic equation of state, p = wrho, is studied. Utilizing the concept of the expansion parameter, it is seen that the cosmic censorship conjecture may be violated for w=-1/3 and w=-2/3 which correspond to the cosmic string and domain wall, respectively. We have shown that physically, it is the rate of collapse that governs the formation of a black hole or a naked singularity as the final fate of dynamical evolution and only for these two cases can the singularity be naked as the collapse end state. Also the weak energy condition is satisfied by the collapsing configuration.

Early caries naked-eyed examination

International Nuclear Information System (INIS)

Bakhmutov, D; Gonchukov, S; Voytenok, O; Kharchenko, O; Zubov, B

2008-01-01

In view of its potential for dental diagnostics, noninvasive optical methods have been the object of research for the last years. Different techniques (spectroscopy, microscopy, and tomography) are used to discriminate between caries and sound enamel. The main aim of this paper is to determine a simple way to see incipient caries with the naked eye

Action on the Surface: Entomopathogenic Fungi versus the Insect Cuticle.

Science.gov (United States)

Ortiz-Urquiza, Almudena; Keyhani, Nemat O

2013-07-16

Infections mediated by broad host range entomopathogenic fungi represent seminal observations that led to one of the first germ theories of disease and are a classic example of a co-evolutionary arms race between a pathogen and target hosts. These fungi are able to parasitize susceptible hosts via direct penetration of the cuticle with the initial and potentially determining interaction occurring between the fungal spore and the insect epicuticle. Entomogenous fungi have evolved mechanisms for adhesion and recognition of host surface cues that help direct an adaptive response that includes the production of: (a) hydrolytic, assimilatory, and/or detoxifying enzymes including lipase/esterases, catalases, cytochrome P450s, proteases, and chitinases; (b) specialized infectious structures, e.g., appressoria or penetrant tubes; and (c) secondary and other metabolites that facilitate infection. Aside from immune responses, insects have evolved a number of mechanisms to keep pathogens at bay that include: (a) the production of (epi) cuticular antimicrobial lipids, proteins, and metabolites; (b) shedding of the cuticle during development; and (c) behavioral-environmental adaptations such as induced fever, burrowing, and grooming, as well as potentially enlisting the help of other microbes, all intended to stop the pathogen before it can breach the cuticle. Virulence and host-defense can be considered to be under constant reciprocal selective pressure, and the action on the surface likely contributes to phenomena such as strain variation, host range, and the increased virulence often noted once a (low) virulent strain is "passaged" through an insect host. Since the cuticle represents the first point of contact and barrier between the fungus and the insect, the "action on the surface" may represent the defining interactions that ultimately can lead either to successful mycosis by the pathogen or successful defense by the host. Knowledge concerning the molecular mechanisms

Constraints on the structure of naked singularities in classical general relativity

International Nuclear Information System (INIS)

Newman, R.P.A.; Joshi, P.S.

1988-01-01

The known examples of naked singularities in general relativity are, in a certain sense, either gravitationally or causally innocuous. A cosmic censorship theorem is formulated and proved to the effect that this behaviour is characteristic of naked singularities in general spacetimes which do not deviate too far from spherical symmetry. copyright 1988 Academic Press, Inc

Cuticle lipids on heteromorphic leaves of Populus euphratica Oliv. growing in riparian habitats differing in available soil moisture.

Science.gov (United States)

Xu, Xiaojing; Xiao, Lei; Feng, Jinchao; Chen, Ningmei; Chen, Yue; Song, Buerbatu; Xue, Kun; Shi, Sha; Zhou, Yijun; Jenks, Matthew A

2016-11-01

Populus euphratica is an important native tree found in arid regions from North Africa and South Europe to China, and is known to tolerate many forms of environmental stress, including drought. We describe cuticle waxes, cutin and cuticle permeability for the heteromorphic leaves of P. euphratica growing in two riparian habitats that differ in available soil moisture. Scanning electron microscopy revealed variation in epicuticular wax crystallization associated with leaf type and site. P. euphratica leaves are dominated by cuticular wax alkanes, primary-alcohols and fatty acids. The major cutin monomers were 10,16-diOH C 16 :0 acids. Broad-ovate leaves (associated with adult phase growth) produced 1.3- and 1.6-fold more waxes, and 2.1- and 0.9-fold more cutin monomers, than lanceolate leaves (associated with juvenile phase growth) at the wetter site and drier site, respectively. The alkane-synthesis-associated ECERIFERUM1 (CER1), as well as ABC transporter- and elongase-associated genes, were expressed at much higher levels at the drier than wetter sites, indicating their potential function in elevating leaf cuticle lipids in the dry site conditions. Higher cuticle lipid amounts were closely associated with lower cuticle permeability (both chlorophyll efflux and water loss). Our results implicate cuticle lipids as among the xeromorphic traits associated with P. euphratica adult-phase broad-ovate leaves. Results here provide useful information for protecting natural populations of P. euphratica and their associated ecosystems, and shed new light on the functional interaction of cuticle and leaf heterophylly in adaptation to more arid, limited-moisture environments. © 2016 Scandinavian Plant Physiology Society.

The Naked Mole Rat Genome Resource: facilitating analyses of cancer and longevity-related adaptations.

Science.gov (United States)

Keane, Michael; Craig, Thomas; Alföldi, Jessica; Berlin, Aaron M; Johnson, Jeremy; Seluanov, Andrei; Gorbunova, Vera; Di Palma, Federica; Lindblad-Toh, Kerstin; Church, George M; de Magalhães, João Pedro

2014-12-15

The naked mole rat (Heterocephalus glaber) is an exceptionally long-lived and cancer-resistant rodent native to East Africa. Although its genome was previously sequenced, here we report a new assembly sequenced by us with substantially higher N50 values for scaffolds and contigs. We analyzed the annotation of this new improved assembly and identified candidate genomic adaptations which may have contributed to the evolution of the naked mole rat's extraordinary traits, including in regions of p53, and the hyaluronan receptors CD44 and HMMR (RHAMM). Furthermore, we developed a freely available web portal, the Naked Mole Rat Genome Resource (http://www.naked-mole-rat.org), featuring the data and results of our analysis, to assist researchers interested in the genome and genes of the naked mole rat, and also to facilitate further studies on this fascinating species. © The Author 2014. Published by Oxford University Press.

Expression of acid-sensing ion channels and selection of reference genes in mouse and naked mole rat.

Science.gov (United States)

Schuhmacher, Laura-Nadine; Smith, Ewan St John

2016-12-13

Acid-sensing ion channels (ASICs) are a family of ion channels comprised of six subunits encoded by four genes and they are expressed throughout the peripheral and central nervous systems. ASICs have been implicated in a wide range of physiological and pathophysiological processes: pain, breathing, synaptic plasticity and excitotoxicity. Unlike mice and humans, naked mole-rats do not perceive acid as a noxious stimulus, even though their sensory neurons express functional ASICs, likely an adaptation to living in a hypercapnic subterranean environment. Previous studies of ASIC expression in the mammalian nervous system have often not examined all subunits, or have failed to adequately quantify expression between tissues; to date there has been no attempt to determine ASIC expression in the central nervous system of the naked mole-rat. Here we perform a geNorm study to identify reliable housekeeping genes in both mouse and naked mole-rat and then use quantitative real-time PCR to estimate the relative amounts of ASIC transcripts in different tissues of both species. We identify RPL13A (ribosomal protein L13A) and CANX (calnexin), and β-ACTIN and EIF4A (eukaryotic initiation factor 4a) as being the most stably expressed housekeeping genes in mouse and naked mole-rat, respectively. In both species, ASIC3 was most highly expressed in dorsal root ganglia (DRG), and ASIC1a, ASIC2b and ASIC3 were more highly expressed across all brain regions compared to the other subunits. We also show that ASIC4, a proton-insensitive subunit of relatively unknown function, was highly expressed in all mouse tissues apart from DRG and hippocampus, but was by contrast the lowliest expressed ASIC in all naked mole-rat tissues.

Deciphering the Evolution and Development of the Cuticle by Studying Lipid Transfer Proteins in Mosses and Liverworts

Directory of Open Access Journals (Sweden)

Tiina A. Salminen

2018-01-01

Full Text Available When plants conquered land, they developed specialized organs, tissues, and cells in order to survive in this new and harsh terrestrial environment. New cell polymers such as the hydrophobic lipid-based polyesters cutin, suberin, and sporopollenin were also developed for protection against water loss, radiation, and other potentially harmful abiotic factors. Cutin and waxes are the main components of the cuticle, which is the waterproof layer covering the epidermis of many aerial organs of land plants. Although the in vivo functions of the group of lipid binding proteins known as lipid transfer proteins (LTPs are still rather unclear, there is accumulating evidence suggesting a role for LTPs in the transfer and deposition of monomers required for cuticle assembly. In this review, we first present an overview of the data connecting LTPs with cuticle synthesis. Furthermore, we propose liverworts and mosses as attractive model systems for revealing the specific function and activity of LTPs in the biosynthesis and evolution of the plant cuticle.

Invariant identification of naked singularities in spherically symmetric spacetimes

International Nuclear Information System (INIS)

Torres, R

2012-01-01

The study of generic naked singularities and their implications for the cosmic censorship conjecture is still an open issue in the framework of general relativity. One of the obstacles can be traced to the procedures for identifying naked singularities. Usually, the methods applied are not only model and coordinate dependent, but they very often rely in some strong assumptions on the degree of differentiability of the physical magnitudes of the model (such as the mass, density, etc) in the singularity. In this paper, we present a coordinate independent framework for identifying naked singularities based on invariants which is also devoid of strong differentiability requirements. The approach is intended to analyse whole families of models and to provide general results related to the cosmic censorship conjecture. Moreover, since the framework has a strict geometrical nature it can be used with alternative theories of gravitation as long as they assume the existence of a Lorentzian manifold. We exemplify its strength by applying it to the study of the collapse of radiation in radiative coordinates and the collapse of dust in comoving coordinates. (paper)

RNAi-Mediated Functional Analysis of Bursicon Genes Related to Adult Cuticle Formation and Tanning in the Honeybee, Apis mellifera.

Directory of Open Access Journals (Sweden)

Claudinéia Pereira Costa

Full Text Available Bursicon is a heterodimeric neurohormone that acts through a G protein-coupled receptor named rickets (rk, thus inducing an increase in cAMP and the activation of tyrosine hydroxylase, the rate-limiting enzyme in the cuticular tanning pathway. In insects, the role of bursicon in the post-ecdysial tanning of the adult cuticle and wing expansion is well characterized. Here we investigated the roles of the genes encoding the bursicon subunits during the adult cuticle development in the honeybee, Apis mellifera. RNAi-mediated knockdown of AmBurs α and AmBurs β bursicon genes prevented the complete formation and tanning (melanization/sclerotization of the adult cuticle. A thinner, much less tanned cuticle was produced, and ecdysis toward adult stage was impaired. Consistent with these results, the knockdown of bursicon transcripts also interfered in the expression of genes encoding its receptor, AmRk, structural cuticular proteins, and enzymes in the melanization/sclerotization pathway, thus evidencing roles for bursicon in adult cuticle formation and tanning. Moreover, the expression of AmBurs α, AmBurs β and AmRk is contingent on the declining ecdysteroid titer that triggers the onset of adult cuticle synthesis and deposition. The search for transcripts of AmBurs α, AmBurs β and candidate targets in RNA-seq libraries prepared with brains and integuments strengthened our data on transcript quantification through RT-qPCR. Together, our results support our premise that bursicon has roles in adult cuticle formation and tanning, and are in agreement with other recent studies pointing for roles during the pharate-adult stage, in addition to the classical post-ecdysial ones.

The architecture of the joint head cuticle and its transition to the arthrodial membrane in the terrestrial crustacean Porcellio scaber.

Science.gov (United States)

Ruangchai, Sukhum; Reisecker, Christian; Hild, Sabine; Ziegler, Andreas

2013-04-01

The cuticle of terrestrial isopods is an interesting model for the study of structure-function relationships in biological composite materials. Its organic matrix has a hierarchically organised structure, and type and phase of the mineral compound can vary. The cuticle forms functionally diverse skeletal elements whose properties are adapted to their specific functions. In order to better understand the relation between structure, composition and function of isopod cuticle, we studied the structure and composition of the joint head that is part of the pereiopod's basis. It consists of a central region, whose shape fits well into the joint socket, and an edge region that is connected to the soft arthrodial membrane and protects the central region from mechanical load. The cuticle architecture of the joint head has local variations in structure and composition. In the central region the cuticle is similar to the previously published tergite cuticle. High concentrations of amorphous calcium phosphate are located in the endocuticle suggesting a coexistence with amorphous calcium carbonate. The edge region has an unexpected organisation characterised by thickening of the epi- and exocuticle and an unusual unidirectional orientation of chitin-protein fibrils within the endocuticle. The concentrations of phosphate are considerably higher than in the central region. The overall differentiation in the cuticular architecture of the edge in comparison to the central region reflects the adaptation to mechanical strains the cuticle has to sustain during contraction of extensor muscles, and to the structural and compositional transition from the edge to the connecting arthrodial membrane. Copyright © 2013 Elsevier Inc. All rights reserved.

Naked mole-rats maintain healthy skeletal muscle and Complex IV mitochondrial enzyme function into old age.

Science.gov (United States)

Stoll, Elizabeth A; Karapavlovic, Nevena; Rosa, Hannah; Woodmass, Michael; Rygiel, Karolina; White, Kathryn; Turnbull, Douglass M; Faulkes, Chris G

2016-12-19

The naked mole-rat (NMR) Heterocephalus glaber is an exceptionally long-lived rodent, living up to 32 years in captivity. This extended lifespan is accompanied by a phenotype of negligible senescence, a phenomenon of very slow changes in the expected physiological characteristics with age. One of the many consequences of normal aging in mammals is the devastating and progressive loss of skeletal muscle, termed sarcopenia, caused in part by respiratory enzyme dysfunction within the mitochondria of skeletal muscle fibers. Here we report that NMRs avoid sarcopenia for decades. Muscle fiber integrity and mitochondrial ultrastructure are largely maintained in aged animals. While mitochondrial Complex IV expression and activity remains stable, Complex I expression is significantly decreased. We show that aged naked mole-rat skeletal muscle tissue contains some mitochondrial DNA rearrangements, although the common mitochondrial DNA deletions associated with aging in human and other rodent skeletal muscles are not present. Interestingly, NMR skeletal muscle fibers demonstrate a significant increase in mitochondrial DNA copy number. These results have intriguing implications for the role of mitochondria in aging, suggesting Complex IV, but not Complex I, function is maintained in the long-lived naked mole rat, where sarcopenia is avoided and healthy muscle function is maintained for decades.

Fruit cuticle lipid composition and fruit post-harvest water loss in an advanced backcross generation of pepper (Capsicum sp.)

KAUST Repository

Parsons, Eugene P.; Popopvsky, Sigal; Lohrey, Gregory T.; Lu, Shiyou; Alkalai-Tuvia, Sharon; Perzelan, Yaacov; Paran, Ilan; Fallik, Elazar; Jenks, Matthew A.

2012-01-01

To understand the role of fruit cuticle lipid composition in fruit water loss, an advanced backcross population, the BC2F2, was created between the Capsicum annuum (PI1154) and the Capsicum chinense (USDA162), which have high and low post-harvest water loss rates, respectively. Besides dramatic differences in fruit water loss, preliminary studies also revealed that these parents exhibited significant differences in both the amount and composition of their fruit cuticle. Cuticle analysis of the BC2F2 fruit revealed that although water loss rate was not strongly associated with the total surface wax amount, there were significant correlations between water loss rate and cuticle composition. We found a positive correlation between water loss rate and the amount of total triterpenoid plus sterol compounds, and negative correlations between water loss and the alkane to triterpenoid plus sterol ratio. We also report negative correlations between water loss rate and the proportion of both alkanes and aliphatics to total surface wax amount. For the first time, we report significant correlations between water loss and cutin monomer composition. We found positive associations of water loss rate with the total cutin, total C16 monomers and 16-dihydroxy hexadecanoic acid. Our results support the hypothesis that simple straight-chain aliphatic cuticle constituents form more impermeable cuticular barriers than more complex isoprenoid-based compounds. These results shed new light on the biochemical basis for cuticle involvement in fruit water loss. © 2012 Physiologia Plantarum.

Fruit cuticle lipid composition and fruit post-harvest water loss in an advanced backcross generation of pepper (Capsicum sp.)

KAUST Repository

Parsons, Eugene P.

2012-03-05

To understand the role of fruit cuticle lipid composition in fruit water loss, an advanced backcross population, the BC2F2, was created between the Capsicum annuum (PI1154) and the Capsicum chinense (USDA162), which have high and low post-harvest water loss rates, respectively. Besides dramatic differences in fruit water loss, preliminary studies also revealed that these parents exhibited significant differences in both the amount and composition of their fruit cuticle. Cuticle analysis of the BC2F2 fruit revealed that although water loss rate was not strongly associated with the total surface wax amount, there were significant correlations between water loss rate and cuticle composition. We found a positive correlation between water loss rate and the amount of total triterpenoid plus sterol compounds, and negative correlations between water loss and the alkane to triterpenoid plus sterol ratio. We also report negative correlations between water loss rate and the proportion of both alkanes and aliphatics to total surface wax amount. For the first time, we report significant correlations between water loss and cutin monomer composition. We found positive associations of water loss rate with the total cutin, total C16 monomers and 16-dihydroxy hexadecanoic acid. Our results support the hypothesis that simple straight-chain aliphatic cuticle constituents form more impermeable cuticular barriers than more complex isoprenoid-based compounds. These results shed new light on the biochemical basis for cuticle involvement in fruit water loss. © 2012 Physiologia Plantarum.

Cuticle scale measurement of animal fibers by SEM and AFM

CSIR Research Space (South Africa)

Notayi, M

2013-12-01

Full Text Available -1 51st Microscopy Society of Southern Africa (MSSA) Conference, Farm Inn, Pretoria, 3-6 December 2013 Cuticle scale measurement of animal fibers by SEM and AFM Notayi M, Engelbrechts JAA, Lee ME, Goosen WE, Hunter L and Botha AF Abstract...

Seasonality influences cuticle melanization and immune defense in a cricket: support for a temperature-dependent immune investment hypothesis in insects

Energy Technology Data Exchange (ETDEWEB)

Fedorka, K. M. [Univ. of Central Florida, Orlando, FL (United States); Copeland, E. K. [Univ. of Central Florida, Orlando, FL (United States); Winterhalter, W. E. [Univ. of Central Florida, Orlando, FL (United States)

2013-07-18

To improve thermoregulation in colder environments, insects are expected to darken their cuticles with melanin via the phenoloxidase cascade, a phenomenon predicted by the thermal melanin hypothesis. However, the phenoloxidase cascade also plays a significant role in insect immunity, leading to the additional hypothesis that the thermal environment indirectly shapes immune function via direct selection on cuticle color. Support for the latter hypothesis comes from the cricket Allonemobius socius, where cuticle darkness and immune-related phenoloxidase activity increase with latitude. However, thermal environments vary seasonally as well as geographically, suggesting that seasonal plasticity in immunity may also exist. Although seasonal fluctuations in vertebrate immune function are common (because of flux in breeding or resource abundance), seasonality in invertebrate immunity has not been widely explored. We addressed this possibility by rearing crickets in simulated summer and fall environments and assayed their cuticle color and immune function. Prior to estimating immunity, crickets were placed in a common environment to minimize metabolic rate differences. Individuals reared under fall-like conditions exhibited darker cuticles, greater phenoloxidase activity and greater resistance to the bacteria Serratia marcescens. These data support the hypothesis that changes in the thermal environment modify cuticle color, which indirectly shapes immune investment through pleiotropy. This hypothesis may represent a widespread mechanism governing immunity in numerous systems, considering that most insects operate in seasonally and geographically variable thermal environments.

New functions of arthropod bursicon: inducing deposition and thickening of new cuticle and hemocyte granulation in the blue crab, Callinectes sapidus.

Directory of Open Access Journals (Sweden)

J Sook Chung

Full Text Available Arthropod growth requires molt-associated changes in softness and stiffness of the cuticle that protects from desiccation, infection and injury. Cuticle hardening in insects depends on the blood-borne hormone, bursicon (Burs, although it has never been determined in hemolymph. Whilst also having Burs, decapod crustaceans reiterate molting many more times during their longer life span and are encased in a calcified exoskeleton, which after molting undergoes similar initial cuticle hardening processes as in insects. We investigated the role of homologous crustacean Burs in cuticular changes and growth in the blue crab, Callinectes sapidus. We found dramatic increases in size and number of Burs cells during development in paired thoracic ganglion complex (TGC neurons with pericardial organs (POs as neurohemal release sites. A skewed expression of Burs β/Burs α mRNA in TGC corresponds to protein contents of identified Burs β homodimer and Burs heterodimer in POs. In hemolymph, Burs is consistently present at ∼21 pM throughout the molt cycle, showing a peak of ∼89 pM at ecdysis. Since initial cuticle hardness determines the degree of molt-associated somatic increment (MSI, we applied recombinant Burs in vitro to cuticle explants of late premolt or early ecdysis. Burs stimulates cuticle thickening and granulation of hemocytes. These findings demonstrate novel cuticle-associated functions of Burs during molting, while the unambiguous and constant presence of Burs in cells and hemolymph throughout the molt cycle and life stages may implicate further functions of its homo- and heterodimer hormone isoforms in immunoprotective defense systems of arthropods.

Chemical Composition and Water Permeability of Fruit and Leaf Cuticles of Olea europaea L.

Science.gov (United States)

Huang, Hua; Burghardt, Markus; Schuster, Ann-Christin; Leide, Jana; Lara, Isabel; Riederer, Markus

2017-10-11

The plant cuticle, protecting against uncontrolled water loss, covers olive (Olea europaea) fruits and leaves. The present study describes the organ-specific chemical composition of the cuticular waxes and the cutin and compares three developmental stages of fruits (green, turning, and black) with the leaf surface. Numerous organ-specific differences, such as the total coverage of cutin monomeric components (1034.4 μg cm -2 and 630.5 μg cm -2 ) and the cuticular waxes (201.6 μg cm -2 and 320.4 μg cm -2 ) among all three fruit stages and leaves, respectively, were detected. Water permeability as the main cuticular function was 5-fold lower in adaxial leaf cuticles (2.1 × 10 -5 m s -1 ) in comparison to all three fruit stages (9.5 × 10 -5 m s -1 ). The three fruit developmental stages have the same cuticular water permeability. It is hypothesized that a higher weighted average chain length of the acyclic cuticular components leads to a considerably lower permeability of the leaf as compared to the fruit cuticle.

A window into extreme longevity; the circulating metabolomic signature of the naked mole-rat, a mammal that shows negligible senescence.

Science.gov (United States)

Lewis, Kaitlyn N; Rubinstein, Nimrod D; Buffenstein, Rochelle

2018-04-20

Mouse-sized naked mole-rats (Heterocephalus glaber), unlike other mammals, do not conform to Gompertzian laws of age-related mortality; adults show no age-related change in mortality risk. Moreover, we observe negligible hallmarks of aging with well-maintained physiological and molecular functions, commonly altered with age in other species. We questioned whether naked mole-rats, living an order of magnitude longer than laboratory mice, exhibit different plasma metabolite profiles, which could then highlight novel mechanisms or targets involved in disease and longevity. Using a comprehensive, unbiased metabolomics screen, we observe striking inter-species differences in amino acid, peptide, and lipid metabolites. Low circulating levels of specific amino acids, particularly those linked to the methionine pathway, resemble those observed during the fasting period at late torpor in hibernating ground squirrels and those seen in longer-lived methionine-restricted rats. These data also concur with metabolome reports on long-lived mutant mice, including the Ames dwarf mice and calorically restricted mice, as well as fruit flies, and even show similarities to circulating metabolite differences observed in young human adults when compared to older humans. During evolution, some of these beneficial nutrient/stress response pathways may have been positively selected in the naked mole-rat. These observations suggest that interventions that modify the aging metabolomic profile to a more youthful one may enable people to lead healthier and longer lives.

Naked-eye 3D imaging employing a modified MIMO micro-ring conjugate mirrors

Science.gov (United States)

Youplao, P.; Pornsuwancharoen, N.; Amiri, I. S.; Thieu, V. N.; Yupapin, P.

2018-03-01

In this work, the use of a micro-conjugate mirror that can produce the 3D image incident probe and display is proposed. By using the proposed system together with the concept of naked-eye 3D imaging, a pixel and a large volume pixel of a 3D image can be created and displayed as naked-eye perception, which is valuable for the large volume naked-eye 3D imaging applications. In operation, a naked-eye 3D image that has a large pixel volume will be constructed by using the MIMO micro-ring conjugate mirror system. Thereafter, these 3D images, formed by the first micro-ring conjugate mirror system, can be transmitted through an optical link to a short distance away and reconstructed via the recovery conjugate mirror at the other end of the transmission. The image transmission is performed by the Fourier integral in MATLAB and compares to the Opti-wave program results. The Fourier convolution is also included for the large volume image transmission. The simulation is used for the manipulation, where the array of a micro-conjugate mirror system is designed and simulated for the MIMO system. The naked-eye 3D imaging is confirmed by the concept of the conjugate mirror in both the input and output images, in terms of the four-wave mixing (FWM), which is discussed and interpreted.

Naked mole-rat acid-sensing ion channel 3 forms nonfunctional homomers, but functional heteromers.

Science.gov (United States)

Schuhmacher, Laura-Nadine; Callejo, Gerard; Srivats, Shyam; Smith, Ewan St John

2018-02-02

Acid-sensing ion channels (ASICs) form both homotrimeric and heterotrimeric ion channels that are activated by extracellular protons and are involved in a wide range of physiological and pathophysiological processes, including pain and anxiety. ASIC proteins can form both homotrimeric and heterotrimeric ion channels. The ASIC3 subunit has been shown to be of particular importance in the peripheral nervous system with pharmacological and genetic manipulations demonstrating a role in pain. Naked mole-rats, despite having functional ASICs, are insensitive to acid as a noxious stimulus and show diminished avoidance of acidic fumes, ammonia, and carbon dioxide. Here we cloned naked mole-rat ASIC3 (nmrASIC3) and used a cell-surface biotinylation assay to demonstrate that it traffics to the plasma membrane, but using whole-cell patch clamp electrophysiology we observed that nmrASIC3 is insensitive to both protons and the non-proton ASIC3 agonist 2-guanidine-4-methylquinazoline. However, in line with previous reports of ASIC3 mRNA expression in dorsal root ganglia neurons, we found that the ASIC3 antagonist APETx2 reversibly inhibits ASIC-like currents in naked mole-rat dorsal root ganglia neurons. We further show that like the proton-insensitive ASIC2b and ASIC4, nmrASIC3 forms functional, proton-sensitive heteromers with other ASIC subunits. An amino acid alignment of ASIC3s between 9 relevant rodent species and human identified unique sequence differences that might underlie the proton insensitivity of nmrASIC3. However, introducing nmrASIC3 differences into rat ASIC3 (rASIC3) produced only minor differences in channel function, and replacing the nmrASIC3 sequence with that of rASIC3 did not produce a proton-sensitive ion channel. Our observation that nmrASIC3 forms nonfunctional homomers may reflect a further adaptation of the naked mole-rat to living in an environment with high-carbon dioxide levels. © 2018 by The American Society for Biochemistry and Molecular

Cuticle hydrolysis in four medically important fly species by enzymes of the entomopathogenic fungus Conidiobolus coronatus.

Science.gov (United States)

Boguś, M I; Włóka, E; Wrońska, A; Kaczmarek, A; Kazek, M; Zalewska, K; Ligęza-Żuber, M; Gołębiowski, M

2017-03-01

Entomopathogenic fungi infect insects via penetration through the cuticle, which varies remarkably in chemical composition across species and life stages. Fungal infection involves the production of enzymes that hydrolyse cuticular proteins, chitin and lipids. Host specificity is associated with fungus-cuticle interactions related to substrate utilization and resistance to host-specific inhibitors. The soil fungus Conidiobolus coronatus (Constantin) (Entomophthorales: Ancylistaceae) shows virulence against susceptible species. The larvae and pupae of Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae), Calliphora vomitoria (Linnaeus), Lucilia sericata (Meigen) (Diptera: Calliphoridae) and Musca domestica (Linnaeus) (Diptera: Muscidae) are resistant, but adults exposed to C. coronatus quickly perish. Fungus was cultivated for 3 weeks in a minimal medium. Cell-free filtrate, for which activity of elastase, N-acetylglucosaminidase, chitobiosidase and lipase was determined, was used for in vitro hydrolysis of the cuticle from larvae, puparia and adults. Amounts of amino acids, N-glucosamine and fatty acids released were measured after 8 h of incubation. The effectiveness of fungal enzymes was correlated with concentrations of compounds detected in the cuticles of tested insects. Positive correlations suggest compounds used by the fungus as nutrients, whereas negative correlations may indicate compounds responsible for insect resistance. Adult deaths result from the ingestion of conidia or fungal excretions. © 2016 The Royal Entomological Society.

Distribution of vasopressin in the brain of the eusocial naked mole-rat.

Science.gov (United States)

Rosen, Greta J; De Vries, Geert J; Goldman, Sharry L; Goldman, Bruce D; Forger, Nancy G

2007-02-20

Naked mole-rats are eusocial rodents that live in large subterranean colonies in which one queen breeds with one to three males. All other animals are nonbreeding subordinates. The external features of male and female subordinates, including their genitalia, are remarkably monomorphic, as is their behavior. Because vasopressin (VP) is associated with social behaviors and sex differences in other species, its distribution in naked mole-rats was of interest. We used immunohistochemistry to examine VP in the brains of subordinate and breeding naked mole-rats of both sexes. As in other mammals, VP-immunoreactive (-ir) somata were found in the paraventricular (PVN) and supraoptic nuclei (SON) and VP-ir projections from these nuclei ran through the internal and external zone of the median eminence. However, naked mole-rats had very few VP-ir cells in the bed nucleus of the stria terminalis (BST) and none in the suprachiasmatic nucleus (SCN); the extensive network of fine-caliber VP-ir fibers usually seen in projection sites of the BST and SCN were also absent. Equally unexpected was the abundance of large-caliber VP-ir fibers in the dorsomedial septum. VP immunoreactivity was generally similar in all groups, with the exception of VP-ir cell number in the dorsomedial hypothalamus (DMH). Breeders had a population of labeled cells in the DMH that was absent, or nearly absent, in subordinates. Future studies on the function of VP in these areas are needed to determine how the atypical distribution of VP immunoreactivity relates to eusociality and the unusual physiology of naked mole-rats.

New analytical techniques for cuticle chemical analysis

International Nuclear Information System (INIS)

Schulten, H.R.

1994-01-01

1) The analytical methodology of pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and direct pyrolysis-mass spectrometry (Py-MS) using soft ionization techniques by high electric fields (FL) are briefly described. Recent advances of Py-GC/MS and Py-FIMS for the analyses of complex organic matter such as plant materials, humic substances, dissolved organic matter in water (DOM) and soil organic matter (SOM) in agricultural and forest soils are given to illustrate the potential and limitations of the applied methods. 2) Novel applications of Py-GC/MS and Py-MS in combination with conventional analytical data in an integrated, chemometric approach to investigate the dynamics of plant lipids are reported. This includes multivariate statistical investigations on maturation, senescence, humus genesis, and environmental damages in spruce ecosystems. 3) The focal point is the author's integrated investigations on emission-induced changes of selected conifer plant constituents. Pattern recognition of Py-MS data of desiccated spruce needles provides a method for distinguishing needles damaged in different ways and determining the cause. Spruce needles were collected from both controls and trees treated with sulphur dioxide (acid rain), nitrogen dioxide, and ozone under controlled conditions. Py-MS and chemometric data evaluation are employed to characterize and classify leaves and their epicuticular waxes. Preliminary mass spectrometric evaluations of isolated cuticles of different plants such as spruce, ivy, holly, and philodendron, as well as ivy cuticles treated in vivo with air pollutants such as surfactants and pesticides are given. (orig.)

The effect of metapleural gland secretion on the growth of a mutualistic bacterium on the cuticle of leaf-cutting ants

DEFF Research Database (Denmark)

Poulsen, Michael; Bot, Adrianne N M; Boomsma, Jacobus J

2003-01-01

In Acromyrmex octospinosus leaf-cutting ants the metapleural glands produce an array of antibiotic compounds that serve as a general defence against unwanted microbes on the cuticle. Leaf-cutting ants also grow mutualistic Pseudonocardiaceae bacteria on their cuticle that produce antibiotics...

Butterfly Wings Are Three-Dimensional: Pupal Cuticle Focal Spots and Their Associated Structures in Junonia Butterflies.

Science.gov (United States)

Taira, Wataru; Otaki, Joji M

2016-01-01

Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.

Butterfly Wings Are Three-Dimensional: Pupal Cuticle Focal Spots and Their Associated Structures in Junonia Butterflies.

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Wataru Taira

Full Text Available Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.

Regulation of cuticle-degrading subtilisin proteases from the entomopathogenic fungi, Lecanicillium spp: implications for host specificity.

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Bye, Natasha J; Charnley, A Keith

2008-01-01

The ability to produce cuticle-degrading proteases to facilitate host penetration does not distinguish per se entomopathogenic fungi from saprophytes. However, adapted pathogens may produce host-protein specific enzymes in response to cues. This possibility prompted an investigation of the regulation of isoforms of the subtilisin Pr1-like proteases from five aphid-pathogenic isolates of Lecanicillium spp. Significant differences were found in substrate specificity and regulation of Pr1-like proteases between isoforms of the same isolate and between different isolates. For example, the pI 8.6 isoform from KV71 was considerably more active against aphid than locust cuticle and was induced specifically by N-acetylglucosamine (NAG). Isoform pI 9.1 from the same isolate was only produced on insect cuticle while most other isoforms were more prominent on chitin containing substrates but not induced by NAG. The ability to regulate isoforms independently may allow production at critical points in host penetration. Appearance of proteases (not subtilisins) with pI 4.2 and 4.4 only on aphid cuticle was a possible link with host specificity of KV71. The absence of C or N metabolite repression in subtilisins from KV42 is unusual for pathogen proteases and may help to account for differences in virulence strategy between aphid-pathogenic isolates of Lecanicillium longisporum (unpublished data).

The fields of a naked singularity and a black hole in mutual equilibrium

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Paolino, Armando; Pizzi, Marco

2008-01-01

Recently Alekseev and Belinski have presented a new exact solution of the Einstein-Maxwell equation which describes two Reissner-Nordstrom (RN) sources in reciprocal equilibrium (no struts nor strings) one source is a naked singularity, the other is a black hole. In this paper we use the Alekseev-Belinki solution in the special case in which the charge of the black hole is zero-therefore we have a naked singularity near a neutral black hole. We give the plots of the electric force lines in both the cases in which the naked singularity has a mass comparable with the black hole and in which it is much smaller. The analysis of this latter case confirm the goodness of the Hanni-Ruffini approximation.

Naked Black Hole Firewalls.

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Chen, Pisin; Ong, Yen Chin; Page, Don N; Sasaki, Misao; Yeom, Dong-Han

2016-04-22

In the firewall proposal, it is assumed that the firewall lies near the event horizon and should not be observable except by infalling observers, who are presumably terminated at the firewall. However, if the firewall is located near where the horizon would have been, based on the spacetime evolution up to that time, later quantum fluctuations of the Hawking emission rate can cause the "teleological" event horizon to have migrated to the inside of the firewall location, rendering the firewall naked. In principle, the firewall can be arbitrarily far outside the horizon. This casts doubt about the notion that firewalls are the "most conservative" solution to the information loss paradox.

Naked Black Hole Firewalls

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Chen, Pisin; Ong, Yen Chin; Page, Don N.; Sasaki, Misao; Yeom, Dong-han

2016-04-01

In the firewall proposal, it is assumed that the firewall lies near the event horizon and should not be observable except by infalling observers, who are presumably terminated at the firewall. However, if the firewall is located near where the horizon would have been, based on the spacetime evolution up to that time, later quantum fluctuations of the Hawking emission rate can cause the "teleological" event horizon to have migrated to the inside of the firewall location, rendering the firewall naked. In principle, the firewall can be arbitrarily far outside the horizon. This casts doubt about the notion that firewalls are the "most conservative" solution to the information loss paradox.

The molecular basis of acid insensitivity in the African naked mole-rat.

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Smith, Ewan St John; Omerbašić, Damir; Lechner, Stefan G; Anirudhan, Gireesh; Lapatsina, Liudmila; Lewin, Gary R

2011-12-16

Acid evokes pain by exciting nociceptors; the acid sensors are proton-gated ion channels that depolarize neurons. The naked mole-rat (Heterocephalus glaber) is exceptional in its acid insensitivity, but acid sensors (acid-sensing ion channels and the transient receptor potential vanilloid-1 ion channel) in naked mole-rat nociceptors are similar to those in other vertebrates. Acid inhibition of voltage-gated sodium currents is more profound in naked mole-rat nociceptors than in mouse nociceptors, however, which effectively prevents acid-induced action potential initiation. We describe a species-specific variant of the nociceptor sodium channel Na(V)1.7, which is potently blocked by protons and can account for acid insensitivity in this species. Thus, evolutionary pressure has selected for an Na(V)1.7 gene variant that tips the balance from proton-induced excitation to inhibition of action potential initiation to abolish acid nociception.

Absence of histamine-induced itch in the African naked mole-rat and "rescue" by Substance P.

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Smith, Ewan St John; Blass, Gregory R C; Lewin, Gary R; Park, Thomas J

2010-05-24

Recent research has proposed a pathway in which sensory neurons expressing the capsaicin activated ion channel TRPV1 are required for histamine-induced itch and subsequent scratching behavior. We examined histamine-induced itch in the African naked mole-rat (Heterocephalus glaber) and found that although naked mole-rats display innate scratching behavior, histamine was unable to evoke increased scratching as is observed in most mouse strains. Using calcium imaging, we examined the histamine sensitivity of naked mole-rat dorsal root ganglia (DRG) neurons and identified a population of small diameter neurons activated by histamine, the majority of which are also capsaicin-sensitive. This suggested that naked mole-rat sensory neurons are activated by histamine, but that spinal dorsal horn processing of sensory information is not the same as in other rodents. We have previously shown that naked mole-rats naturally lack substance P (SP) in cutaneous C-fibers, but that the neurokinin-1 receptor is expressed in the superficial spinal cord. This led us to investigate if SP deficiency plays a role in the lack of histamine-induced scratching in this species. After intrathecal administration of SP into the spinal cord we observed robust scratching behavior in response to histamine injection. Our data therefore support a model in which TRPV1-expressing sensory neurons are important for histamine-induced itch. In addition, we demonstrate a requirement for active, SP-induced post-synaptic drive to enable histamine sensitive afferents to drive itch-related behavior in the naked mole-rat. These results illustrate that it is altered dorsal horn connectivity of nociceptors that underlies the lack of itch and pain-related behavior in the naked mole-rat.

Absence of histamine-induced itch in the African naked mole-rat and "rescue" by Substance P

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Lewin Gary R

2010-05-01

Full Text Available Abstract Recent research has proposed a pathway in which sensory neurons expressing the capsaicin activated ion channel TRPV1 are required for histamine-induced itch and subsequent scratching behavior. We examined histamine-induced itch in the African naked mole-rat (Heterocephalus glaber and found that although naked mole-rats display innate scratching behavior, histamine was unable to evoke increased scratching as is observed in most mouse strains. Using calcium imaging, we examined the histamine sensitivity of naked mole-rat dorsal root ganglia (DRG neurons and identified a population of small diameter neurons activated by histamine, the majority of which are also capsaicin-sensitive. This suggested that naked mole-rat sensory neurons are activated by histamine, but that spinal dorsal horn processing of sensory information is not the same as in other rodents. We have previously shown that naked mole-rats naturally lack substance P (SP in cutaneous C-fibers, but that the neurokinin-1 receptor is expressed in the superficial spinal cord. This led us to investigate if SP deficiency plays a role in the lack of histamine-induced scratching in this species. After intrathecal administration of SP into the spinal cord we observed robust scratching behavior in response to histamine injection. Our data therefore support a model in which TRPV1-expressing sensory neurons are important for histamine-induced itch. In addition, we demonstrate a requirement for active, SP-induced post-synaptic drive to enable histamine sensitive afferents to drive itch-related behavior in the naked mole-rat. These results illustrate that it is altered dorsal horn connectivity of nociceptors that underlies the lack of itch and pain-related behavior in the naked mole-rat.

The anti-tumorigenic activity of A2M-A lesson from the naked mole-rat.

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Kurz, Susanne; Thieme, René; Amberg, Ronny; Groth, Marco; Jahnke, Heinz-Georg; Pieroh, Philipp; Horn, Lars-Christian; Kolb, Marlen; Huse, Klaus; Platzer, Matthias; Volke, Daniela; Dehghani, Faramarz; Buzdin, Anton; Engel, Kathrin; Robitzki, Andrea; Hoffmann, Ralf; Gockel, Ines; Birkenmeier, Gerd

2017-01-01

Cancer resistance is a major cause for longevity of the naked mole-rat. Recent liver transcriptome analysis in this animal compared to wild-derived mice revealed higher expression of alpha2-macroglobulin (A2M) and cell adhesion molecules, which contribute to the naked mole-rat's cancer resistance. Notably, A2M is known to dramatically decrease with age in humans. We hypothesize that this might facilitate tumour development. Here we found that A2M modulates tumour cell adhesion, migration and growth by inhibition of tumour promoting signalling pathways, e.g. PI3K / AKT, SMAD and up-regulated PTEN via down-regulation of miR-21, in vitro and in tumour xenografts. A2M increases the expression of CD29 and CD44 but did not evoke EMT. Transcriptome analysis of A2M-treated tumour cells, xenografts and mouse liver demonstrated a multifaceted regulation of tumour promoting signalling pathways indicating a less tumorigenic environment mediated by A2M. By virtue of these multiple actions the naturally occurring A2M has strong potential as a novel therapeutic agent.

Optical effects related to Keplerian discs orbiting Kehagias-Sfetsos naked singularities

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Stuchlík, Zdeněk; Schee, Jan

2014-10-01

We demonstrate possible optical signatures of the Kehagias-Sfetsos (KS) naked singularity spacetimes representing a spherically symmetric vacuum solution of the modified Hořava gravity. In such spacetimes, accretion structures significantly different from those present in standard black hole spacetimes occur due to the ‘antigravity’ effect, which causes an internal static sphere surrounded by Keplerian discs. We focus our attention on the optical effects related to the Keplerian accretion discs, constructing the optical appearance of the Keplerian discs, the spectral continuum due to their thermal radiation, and the spectral profiled lines generated in the innermost parts of such discs. The KS naked singularity signature is strongly encoded in the characteristics of predicted optical effects, especially in cases where the spectral continuum and spectral lines are profiled by the strong gravity of the spacetimes due to the vanishing region of the angular velocity gradient influencing the effectiveness of the viscosity mechanism. We can conclude that optical signatures of KS naked singularities can be well distinguished from the signatures of standard black holes.

Optical effects related to Keplerian discs orbiting Kehagias–Sfetsos naked singularities

International Nuclear Information System (INIS)

Stuchlík, Zdeněk; Schee, Jan

2014-01-01

We demonstrate possible optical signatures of the Kehagias–Sfetsos (KS) naked singularity spacetimes representing a spherically symmetric vacuum solution of the modified Hořava gravity. In such spacetimes, accretion structures significantly different from those present in standard black hole spacetimes occur due to the ‘antigravity’ effect, which causes an internal static sphere surrounded by Keplerian discs. We focus our attention on the optical effects related to the Keplerian accretion discs, constructing the optical appearance of the Keplerian discs, the spectral continuum due to their thermal radiation, and the spectral profiled lines generated in the innermost parts of such discs. The KS naked singularity signature is strongly encoded in the characteristics of predicted optical effects, especially in cases where the spectral continuum and spectral lines are profiled by the strong gravity of the spacetimes due to the vanishing region of the angular velocity gradient influencing the effectiveness of the viscosity mechanism. We can conclude that optical signatures of KS naked singularities can be well distinguished from the signatures of standard black holes. (paper)

Papapetrou's naked singularity is a strong curvature singularity

International Nuclear Information System (INIS)

Hollier, G.P.

1986-01-01

Following Papapetrou [1985, a random walk in General Relativity ed. J. Krishna-Rao (New Delhi: Wiley Eastern)], a spacetime with a naked singularity is analysed. This singularity is shown to be a strong curvature singularity and thus a counterexample to a censorship conjecture. (author)

CFLAP1 and CFLAP2 Are Two bHLH Transcription Factors Participating in Synergistic Regulation of AtCFL1-Mediated Cuticle Development in Arabidopsis.

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Shibai Li

2016-01-01

Full Text Available The cuticle is a hydrophobic lipid layer covering the epidermal cells of terrestrial plants. Although many genes involved in Arabidopsis cuticle development have been identified, the transcriptional regulation of these genes is largely unknown. Previously, we demonstrated that AtCFL1 negatively regulates cuticle development by interacting with the HD-ZIP IV transcription factor HDG1. Here, we report that two bHLH transcription factors, AtCFL1 associated protein 1 (CFLAP1 and CFLAP2, are also involved in AtCFL1-mediated regulation of cuticle development. CFLAP1 and CFLAP2 interact with AtCFL1 both in vitro and in vivo. Overexpression of either CFLAP1 or CFLAP2 led to expressional changes of genes involved in fatty acids, cutin and wax biosynthesis pathways and caused multiple cuticle defective phenotypes such as organ fusion, breakage of the cuticle layer and decreased epicuticular wax crystal loading. Functional inactivation of CFLAP1 and CFLAP2 by chimeric repression technology caused opposite phenotypes to the CFLAP1 overexpressor plants. Interestingly, we find that, similar to the transcription factor HDG1, the function of CFLAP1 in cuticle development is dependent on the presence of AtCFL1. Furthermore, both HDG1 and CFLAP1/2 interact with the same C-terminal C4 zinc finger domain of AtCFL1, a domain that is essential for AtCFL1 function. These results suggest that AtCFL1 may serve as a master regulator in the transcriptional regulation of cuticle development, and that CFLAP1 and CFLAP2 are involved in the AtCFL1-mediated regulation pathway, probably through competing with HDG1 to bind to AtCFL1.

High Autophagy in the Naked Mole Rat may Play a Significant Role in Maintaining Good Health

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Shanmin Zhao

2014-02-01

Full Text Available Background/Aims: The maximum lifespan of the naked mole rat is over 28.3 years, which exceeds that of any other rodent species, suggesting that age-related changes in its body composition and functionality are either attenuated or delayed in this extraordinarily long-lived species. However, the mechanisms underlying the aging process in this species are poorly understood. In this study, we investigated whether long-lived naked mole rats display more autophagic activity than short-lived mice. Methods: Hepatic stellate cells isolated from naked mole rats were treated with 50 nM rapamycin or 20 mM 3-methyladenine (3-MA for 12 or 24 h. Expression of the autophagy marker proteins LC3-II and beclin 1 was measured with western blotting and immunohistochemistry. The induction of apoptosis was analyzed by flow cytometry. Results: Our results demonstrate that one-day-old naked mole rats have higher levels of autophagy than one-day-old short-lived C57BL/6 mice, and that both adult naked mole rats (eight months old and adult C57BL/6 mice (eight weeks old have high basal levels of autophagy, which may be an important mechanism inhibiting aging and reducing the risk of age-related diseases. Conclusion: Here, we report that autophagy facilitated the survival of hepatic stellate cells from the naked mole rat, and that treatment with 3-MA or rapamycin increased the ratio of apoptotic cells to normal hepatic stellate cells.

Unraveling the message: insights into comparative genomics of the naked mole-rat.

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Lewis, Kaitlyn N; Soifer, Ilya; Melamud, Eugene; Roy, Margaret; McIsaac, R Scott; Hibbs, Matthew; Buffenstein, Rochelle

2016-08-01

Animals have evolved to survive, and even thrive, in different environments. Genetic adaptations may have indirectly created phenotypes that also resulted in a longer lifespan. One example of this phenomenon is the preternaturally long-lived naked mole-rat. This strictly subterranean rodent tolerates hypoxia, hypercapnia, and soil-based toxins. Naked mole-rats also exhibit pronounced resistance to cancer and an attenuated decline of many physiological characteristics that often decline as mammals age. Elucidating mechanisms that give rise to their unique phenotypes will lead to better understanding of subterranean ecophysiology and biology of aging. Comparative genomics could be a useful tool in this regard. Since the publication of a naked mole-rat genome assembly in 2011, analyses of genomic and transcriptomic data have enabled a clearer understanding of mole-rat evolutionary history and suggested molecular pathways (e.g., NRF2-signaling activation and DNA damage repair mechanisms) that may explain the extraordinarily longevity and unique health traits of this species. However, careful scrutiny and re-analysis suggest that some identified features result from incorrect or imprecise annotation and assembly of the naked mole-rat genome: in addition, some of these conclusions (e.g., genes involved in cancer resistance and hairlessness) are rejected when the analysis includes additional, more closely related species. We describe how the combination of better study design, improved genomic sequencing techniques, and new bioinformatic and data analytical tools will improve comparative genomics and ultimately bridge the gap between traditional model and nonmodel organisms.

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

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Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, PO Box 5300, Nova Scotia, B1P 6L2 Sydney (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, 47405-2208 Bloomington, IN (United States)

2001-07-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH{sub 2}/CH{sub 3} ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed.

Naked-eye astronomy in mass tourism

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Tadić Milutin

2016-01-01

Full Text Available This paper considers the possibility of developing astro-tourism in small countries such as Serbia and other Balkan countries, with "discreet" astro-tourism reduced to naked-eye astronomy as part of mass tourism rather than elite tourism that is realized through specialized programs with spacecraft and space stations, spectacular planetariums and observatories with giant telescopes. The specific relationship between the virtual and the real world is highlighted in this paper especially when considering younger generations. Furthermore, the differences in the way stars are perceived by astronomers and "ordinary" tourists or non-astronomers is also emphasized. Tourists are not enchanted by celestial bodies themselves, but by a complete scene, which consists of integrated skyscapes and landscapes, as a complex stage where in various combinations and forms these celestial bodies are observed, and of their own experience. These complex sky-earth landscapes, astro-landscapes, present astro-tourism resources of the small countries like Serbia, provided that a tourist can "read" their astronomical text. In this regard, Belgrade was used as the example for drafting a "package" of astronomical information that can be easily prepared and adapted according to the needs of a particular group, so that every tourist may know what can be seen, where and when. With the help of a rotating star map (planisphere, visitors may observe the sky with the naked eye.

Two-Laser Interference Visible to the Naked Eye

Science.gov (United States)

Kawalec, Tomasz; Bartoszek-Bober, Dobroslawa

2012-01-01

An experimental setup allowing the observation of two-laser interference by the naked eye is described. The key concept is the use of an electronic phase lock between two external cavity diode lasers. The experiment is suitable both for undergraduate and graduate students, mainly in atomic physics laboratories. It gives an opportunity for…

Structural changes in cuticles on violin bow hair caused by wear.

Science.gov (United States)

Yamamoto, Tomoko; Sugiyama, Shigeru

2010-01-01

A bow with horse tail hair is used to play the violin. New and worn-out bow hairs were observed by atomic force microscopy. The cuticles of the new bow hair were already damaged by bleach and delipidation, however the worn-out bow hairs were much more damaged and broken off by force, which relates to wearing out.

The anti-tumorigenic activity of A2M-A lesson from the naked mole-rat.

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Susanne Kurz

Full Text Available Cancer resistance is a major cause for longevity of the naked mole-rat. Recent liver transcriptome analysis in this animal compared to wild-derived mice revealed higher expression of alpha2-macroglobulin (A2M and cell adhesion molecules, which contribute to the naked mole-rat's cancer resistance. Notably, A2M is known to dramatically decrease with age in humans. We hypothesize that this might facilitate tumour development. Here we found that A2M modulates tumour cell adhesion, migration and growth by inhibition of tumour promoting signalling pathways, e.g. PI3K / AKT, SMAD and up-regulated PTEN via down-regulation of miR-21, in vitro and in tumour xenografts. A2M increases the expression of CD29 and CD44 but did not evoke EMT. Transcriptome analysis of A2M-treated tumour cells, xenografts and mouse liver demonstrated a multifaceted regulation of tumour promoting signalling pathways indicating a less tumorigenic environment mediated by A2M. By virtue of these multiple actions the naturally occurring A2M has strong potential as a novel therapeutic agent.

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

Science.gov (United States)

Zodrow, E.L.; Mastalerz, Maria

2001-01-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH2/CH3 ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed. ?? 2001 Elsevier Science B.V. All rights reserved.

Naked mole-rat mortality rates defy Gompertzian laws by not increasing with age

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Ruby, J Graham; Smith, Megan

2018-01-01

The longest-lived rodent, the naked mole-rat (Heterocephalus glaber), has a reported maximum lifespan of >30 years and exhibits delayed and/or attenuated age-associated physiological declines. We questioned whether these mouse-sized, eusocial rodents conform to Gompertzian mortality laws by experiencing an exponentially increasing risk of death as they get older. We compiled and analyzed a large compendium of historical naked mole-rat lifespan data with >3000 data points. Kaplan-Meier analyses revealed a substantial portion of the population to have survived at 30 years of age. Moreover, unlike all other mammals studied to date, and regardless of sex or breeding-status, the age-specific hazard of mortality did not increase with age, even at ages 25-fold past their time to reproductive maturity. This absence of hazard increase with age, in defiance of Gompertz’s law, uniquely identifies the naked mole-rat as a non-aging mammal, confirming its status as an exceptional model for biogerontology. PMID:29364116

Analysis of Alpha-2 Macroglobulin from the Long-Lived and Cancer-Resistant Naked Mole-Rat and Human Plasma.

Science.gov (United States)

Thieme, René; Kurz, Susanne; Kolb, Marlen; Debebe, Tewodros; Holtze, Susanne; Morhart, Michaela; Huse, Klaus; Szafranski, Karol; Platzer, Matthias; Hildebrandt, Thomas B; Birkenmeier, Gerd

2015-01-01

The naked mole-rat (NMR) is a long-lived and cancer resistant species. Identification of potential anti-cancer and age related mechanisms is of great interest and makes this species eminent to investigate anti-cancer strategies and understand aging mechanisms. Since it is known that the NMR expresses higher liver mRNA-levels of alpha 2-macroglobulin than mice, nothing is known about its structure, functionality or expression level in the NMR compared to the human A2M. Here we show a comprehensive analysis of NMR- and human plasma-A2M, showing a different prediction in glycosylation of NMR-A2M, which results in a higher molecular weight compared to human A2M. Additionally, we found a higher concentration of A2M (8.3±0.44 mg/mL vs. and 4.4±0.20 mg/mL) and a lower total plasma protein content (38.7±1.79 mg/mL vs. 61.7±3.20 mg/mL) in NMR compared to human. NMR-A2M can be transformed by methylamine and trypsin resulting in a conformational change similar to human A2M. NMR-A2M is detectable by a polyclonal antibody against human A2M. Determination of tryptic and anti-tryptic activity of NMR and human plasma revealed a higher anti-tryptic activity of the NMR plasma. On the other hand, less proteolytic activity was found in NMR plasma compared to human plasma. We found transformed NMR-A2M binding to its specific receptor LRP1. We could demonstrate lower protein expression of LRP1 in the NMR liver tissue compared to human but higher expression of A2M. This was accompanied by a higher EpCAM protein expression as central adhesion molecule in cancer progression. NMR-plasma was capable to increase the adhesion in human fibroblast in vitro most probably by increasing CD29 protein expression. This is the first report, demonstrating similarities as well as distinct differences between A2M in NMR and human plasma. This might be directly linked to the intriguing phenotype of the NMR and suggests that A2M might probably play an important role in anti-cancer and the anti

Analysis of Alpha-2 Macroglobulin from the Long-Lived and Cancer-Resistant Naked Mole-Rat and Human Plasma.

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René Thieme

Full Text Available The naked mole-rat (NMR is a long-lived and cancer resistant species. Identification of potential anti-cancer and age related mechanisms is of great interest and makes this species eminent to investigate anti-cancer strategies and understand aging mechanisms. Since it is known that the NMR expresses higher liver mRNA-levels of alpha 2-macroglobulin than mice, nothing is known about its structure, functionality or expression level in the NMR compared to the human A2M.Here we show a comprehensive analysis of NMR- and human plasma-A2M, showing a different prediction in glycosylation of NMR-A2M, which results in a higher molecular weight compared to human A2M. Additionally, we found a higher concentration of A2M (8.3±0.44 mg/mL vs. and 4.4±0.20 mg/mL and a lower total plasma protein content (38.7±1.79 mg/mL vs. 61.7±3.20 mg/mL in NMR compared to human. NMR-A2M can be transformed by methylamine and trypsin resulting in a conformational change similar to human A2M. NMR-A2M is detectable by a polyclonal antibody against human A2M. Determination of tryptic and anti-tryptic activity of NMR and human plasma revealed a higher anti-tryptic activity of the NMR plasma. On the other hand, less proteolytic activity was found in NMR plasma compared to human plasma.We found transformed NMR-A2M binding to its specific receptor LRP1. We could demonstrate lower protein expression of LRP1 in the NMR liver tissue compared to human but higher expression of A2M. This was accompanied by a higher EpCAM protein expression as central adhesion molecule in cancer progression. NMR-plasma was capable to increase the adhesion in human fibroblast in vitro most probably by increasing CD29 protein expression. This is the first report, demonstrating similarities as well as distinct differences between A2M in NMR and human plasma. This might be directly linked to the intriguing phenotype of the NMR and suggests that A2M might probably play an important role in anti-cancer and the

The Naked Mole Rat Genome Resource : facilitating analyses of cancer and longevity-related adaptations

OpenAIRE

Keane, Michael; Craig, Thomas; Alfoldi, Jessica; Berlin, Aaron M; Johnson, Jeremy; Seluanov, Andrei; Gorbunova, Vera; Di Palma, Federica; Lindblad-Toh, Kerstin; Church, George M; de Magalhaes, Joao Pedro

2014-01-01

MOTIVATION: The naked mole rat (Heterocephalus glaber) is an exceptionally long-lived and cancer-resistant rodent native to East Africa. Although its genome was previously sequenced, here we report a new assembly sequenced by us with substantially higher N50 values for scaffolds and contigs. RESULTS: We analyzed the annotation of this new improved assembly and identified candidate genomic adaptations which may have contributed to the evolution of the naked mole rat's extraordinary traits, inc...

Sex, social status, and CRF receptor densities in naked mole-rats.

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Beery, Annaliese K; Bicks, Lucy; Mooney, Skyler J; Goodwin, Nastacia L; Holmes, Melissa M

2016-02-01

Naked mole-rats (Heterocephalus glaber) live in groups that are notable for their large size and caste structure, with breeding monopolized by a single female and a small number of males. Recent studies have demonstrated substantial differences between the brains of breeders and subordinates induced by changes in social standing. Corticotropin-releasing factor (CRF) receptors-which bind the hormone CRF as well as related peptides-are important regulators of stress and anxiety, and are emerging as factors affecting social behavior. We conducted autoradiographic analyses of CRF1 and CRF2 receptor binding densities in female and male naked mole-rats varying in breeding status. Both globally and in specific brain regions, CRF1 receptor densities varied with breeding status. CRF1 receptor densities were higher in subordinates across brain regions, and particularly in the piriform cortex and cortical amygdala. Sex differences were present in CRF2 receptor binding densities, as is the case in multiple vole species. CRF2 receptor densities were higher in females, both globally and in the cortical amygdala and lateral amygdalar nucleus. These results provide novel insights into the neurobiology of social hierarchy in naked mole-rats, and add to a growing body of work that links changes in the CRF system with social behavior. © 2015 Wiley Periodicals, Inc.

On the nature of naked singularities in Vaidya spacetimes

Energy Technology Data Exchange (ETDEWEB)

Dwivedi, I.H. (Aligarh Muslim Univ. (India). Dept. of Physics); Joshi, P.S. (Tata Inst. of Fundamental Research, Bombay (India))

1989-11-01

The Vaidya-Papapetrou model containing a naked singularity is analysed for outgoing causal geodesics joining the singularity. The curvature growth along these trajectories is examined to show that this is a strong curvature singularity, providing a counter-example to certain forms of cosmic censorship hypotheses. (author).

On the nature of naked singularities in Vaidya spacetimes

International Nuclear Information System (INIS)

Dwivedi, I.H.

1989-01-01

The Vaidya-Papapetrou model containing a naked singularity is analysed for outgoing causal geodesics joining the singularity. The curvature growth along these trajectories is examined to show that this is a strong curvature singularity, providing a counter-example to certain forms of cosmic censorship hypotheses. (author)

Membrane phospholipid composition may contribute to exceptional longevity of the naked mole-rat (Heterocephalus glaber): a comparative study using shotgun lipidomics.

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Mitchell, Todd W; Buffenstein, Rochelle; Hulbert, A J

2007-11-01

Phospholipids containing highly polyunsaturated fatty acids are particularly prone to peroxidation and membrane composition may therefore influence longevity. Phospholipid molecules, in particular those containing docosahexaenoic acid (DHA), from the skeletal muscle, heart, liver and liver mitochondria were identified and quantified using mass-spectrometry shotgun lipidomics in two similar-sized rodents that show an approximately 9-fold difference in maximum lifespan. The naked mole rat is the longest-living rodent known with a maximum lifespan of >28 years. Total phospholipid distribution is similar in tissues of both species; DHA is only found in phosphatidylcholines (PC), phosphatidylethanolamines (PE) and phosphatidylserines (PS), and DHA is relatively more concentrated in PE than PC. Naked mole-rats have fewer molecular species of both PC and PE than do mice. DHA-containing phospholipids represent 27-57% of all phospholipids in mice but only 2-6% in naked mole-rats. Furthermore, while mice have small amounts of di-polyunsaturated PC and PE, these are lacking in naked mole-rats. Vinyl ether-linked phospholipids (plasmalogens) are higher in naked mole-rat tissues than in mice. The lower level of DHA-containing phospholipids suggests a lower susceptibility to peroxidative damage in membranes of naked mole-rats compared to mice. Whereas the high level of plasmalogens might enhance membrane antioxidant protection in naked mole-rats compared to mice. Both characteristics possibly contribute to the exceptional longevity of naked mole-rats and may indicate a special role for peroxisomes in this extended longevity.

Carcass characteristics, physical property and chemical composition of Naked-Neck and Thai indigenous chickens muscles reared under backyard production systems

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Songsang, A.

2007-03-01

Full Text Available The objective of this study was to obtain basic knowledge regarding carcass characteristics, physical property and chemical composition of the muscle meat of Naked-Neck and indigenous chickens reared underthe backyard production systems. Ninety heads each of Naked-Neck and indigenous chickens of both sexes at 1.3, 1.5 and 1.8 kg of live weight were used in the study. From this study, there were no significant differences (P>0.05 in the chilled carcass percentage between the two breeds and two sexes. The Naked-Neckchickens had lower breast (Pectoralis major, fillet (Pectoralis minor (P0.05 in drip loss and cooking loss values. The shear value of cooked breast and thigh muscles of Naked-Neck chickens was significantly lower (P0.05, redness (a* (P0.05 in moisture, protein, fat and ash contents. The Naked-Neck chicken contained higher (P0.05 between breeds in soluble collagen percentage of both types of muscles. For the fatty acid composition ofNaked-Neck and indigenous chickens, both breast and thigh muscles contained more saturated fatty acids than unsaturated fatty acids.

Four Cases of Spontaneous Neoplasia in the Naked Mole-Rat (Heterocephalus glaber), A Putative Cancer-Resistant Species.

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Taylor, Kyle R; Milone, Nicholas A; Rodriguez, Carlos E

2017-01-01

The naked mole-rat (Heterocephalus glaber) is widely acclaimed to be cancer-resistant and of considerable research interest based on a paucity of reports of neoplasia in this species. We have, however, encountered four spontaneous cases of neoplasia and one presumptive case of neoplasia through routine necropsy and biopsy of individuals in a zoo collection of nonhybrid naked mole-rats bred from a single pair. One case each of metastasizing hepatocellular carcinoma, nephroblastoma (Wilms' tumor), and multicentric lymphosarcoma, as well as presumptive esophageal adenocarcinoma (Barrett's esophagus-like) was identified postmortem among 37 nonautolyzed necropsy submissions of naked mole-rats over 1-year-old that were submitted for necropsy between 1998 and August 2015. One incidental case of cutaneous hemangioma was also identified antemortem by skin biopsy from one naked mole-rat examined for trauma. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Caenorhabditis elegans BAH-1 is a DUF23 protein expressed in seam cells and required for microbial biofilm binding to the cuticle.

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Kevin Drace

2009-08-01

Full Text Available The cuticle of Caenorhabditis elegans, a complex, multi-layered extracellular matrix, is a major interface between the animal and its environment. Biofilms produced by the bacterial genus Yersinia attach to the cuticle of the worm, providing an assay for surface characteristics. A C. elegans gene required for biofilm attachment, bah-1, encodes a protein containing the domain of unknown function DUF23. The DUF23 domain is found in 61 predicted proteins in C. elegans, which can be divided into three distinct phylogenetic clades. bah-1 is expressed in seam cells, which are among the hypodermal cells that synthesize the cuticle, and is regulated by a TGF-beta signaling pathway.

Investigation of the presence and antinociceptive function of muscarinic acetylcholine receptors in the African naked mole-rat (Heterocephalus glaber).

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Jørgensen, Kristine B; Krogh-Jensen, Karen; Pickering, Darryl S; Kanui, Titus I; Abelson, Klas S P

2016-01-01

The present study investigated the cholinergic system in the African naked mole-rat (Heterocephalus glaber) with focus on the muscarinic acetylcholine receptor subtypes M1 and M4. The protein sequences for the subtypes m 1-5 of the naked mole-rat were compared to that of the house mouse (Mus musculus) using basic local alignment search tool (BLAST). The presence and function of M1 and M4 was investigated in vivo, using the formalin test with the muscarinic receptor agonists xanomeline and VU0152100. Spinal cord tissue from the naked mole-rat was used for receptor saturation binding studies with [(3)H]-N-methylscopolamine. The BLAST test revealed 95 % protein sequence homology showing the naked mole-rat to have the genetic potential to express all five muscarinic acetylcholine receptor subtypes. A significant reduction in pain behavior was demonstrated after administration of 8.4 mg/kg in the formalin test. Administration of 50 mg/kg VU0152100 resulted in a non-significant tendency towards antinociception. The antinociceptive effects were reversed by the muscarinic acetylcholine receptor antagonist atropine. Binding studies indicated presence of muscarinic acetylcholine receptors with a radioligand affinity comparable to that reported in mice. In conclusion, muscarinic acetylcholine receptor subtypes are present in the naked mole-rat and contribute to antinociception in the naked mole-rat.

Papapetrou's naked singularity is a strong curvature singularity

Energy Technology Data Exchange (ETDEWEB)

Hollier, G.P.

1986-11-01

Following Papapetrou (1985, a random walk in General Relativity ed. J. Krishna-Rao (New Delhi: Wiley Eastern)), a spacetime with a naked singularity is analysed. This singularity is shown to be a strong curvature singularity and thus a counterexample to a censorship conjecture.

RNA sequencing reveals differential expression of mitochondrial and oxidation reduction genes in the long-lived naked mole-rat when compared to mice.

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Yu, Chuanfei; Li, Yang; Holmes, Andrew; Szafranski, Karol; Faulkes, Chris G; Coen, Clive W; Buffenstein, Rochelle; Platzer, Matthias; de Magalhães, João Pedro; Church, George M

2011-01-01

The naked mole-rat (Heterocephalus glaber) is a long-lived, cancer resistant rodent and there is a great interest in identifying the adaptations responsible for these and other of its unique traits. We employed RNA sequencing to compare liver gene expression profiles between naked mole-rats and wild-derived mice. Our results indicate that genes associated with oxidoreduction and mitochondria were expressed at higher relative levels in naked mole-rats. The largest effect is nearly 300-fold higher expression of epithelial cell adhesion molecule (Epcam), a tumour-associated protein. Also of interest are the protease inhibitor, alpha2-macroglobulin (A2m), and the mitochondrial complex II subunit Sdhc, both ageing-related genes found strongly over-expressed in the naked mole-rat. These results hint at possible candidates for specifying species differences in ageing and cancer, and in particular suggest complex alterations in mitochondrial and oxidation reduction pathways in the naked mole-rat. Our differential gene expression analysis obviated the need for a reference naked mole-rat genome by employing a combination of Illumina/Solexa and 454 platforms for transcriptome sequencing and assembling transcriptome contigs of the non-sequenced species. Overall, our work provides new research foci and methods for studying the naked mole-rat's fascinating characteristics.

RNA sequencing reveals differential expression of mitochondrial and oxidation reduction genes in the long-lived naked mole-rat when compared to mice.

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Chuanfei Yu

Full Text Available The naked mole-rat (Heterocephalus glaber is a long-lived, cancer resistant rodent and there is a great interest in identifying the adaptations responsible for these and other of its unique traits. We employed RNA sequencing to compare liver gene expression profiles between naked mole-rats and wild-derived mice. Our results indicate that genes associated with oxidoreduction and mitochondria were expressed at higher relative levels in naked mole-rats. The largest effect is nearly 300-fold higher expression of epithelial cell adhesion molecule (Epcam, a tumour-associated protein. Also of interest are the protease inhibitor, alpha2-macroglobulin (A2m, and the mitochondrial complex II subunit Sdhc, both ageing-related genes found strongly over-expressed in the naked mole-rat. These results hint at possible candidates for specifying species differences in ageing and cancer, and in particular suggest complex alterations in mitochondrial and oxidation reduction pathways in the naked mole-rat. Our differential gene expression analysis obviated the need for a reference naked mole-rat genome by employing a combination of Illumina/Solexa and 454 platforms for transcriptome sequencing and assembling transcriptome contigs of the non-sequenced species. Overall, our work provides new research foci and methods for studying the naked mole-rat's fascinating characteristics.

Adult naked mole-rat brain retains the NMDA receptor subunit GluN2D associated with hypoxia tolerance in neonatal mammals.

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Peterson, Bethany L; Park, Thomas J; Larson, John

2012-01-11

Adult naked mole-rats show a number of systemic adaptations to a crowded underground habitat that is low in oxygen and high in carbon dioxide. Remarkably, brain slice tissue from adult naked mole-rats also is extremely tolerant to oxygen deprivation as indicated by maintenance of synaptic transmission under hypoxic conditions as well as by a delayed neuronal depolarization during anoxia. These characteristics resemble hypoxia tolerance in brain slices from neonates in a variety of mammal species. An important component of neonatal tolerance to hypoxia involves the subunit composition of NMDA receptors. Neonates have a high proportion of NMDA receptors with GluN2D subunits which are protective because they retard calcium entry into neurons during hypoxic episodes. Therefore, we hypothesized that adult naked mole-rats retain a protective, neonatal-like, NMDA receptor subunit profile. We used immunoblotting to assess age-related changes in NMDA receptor subunits in naked mole-rats and mice. The results show that adult naked mole-rat brain retains a much greater proportion of the hypoxia-protective GluN2D subunit compared to adult mice. However, age-related changes in other subunits (GluN2A and GluN2B) from the neonatal period to adulthood were comparable in mice and naked mole-rats. Hence, adult naked mole-rat brain only retains the neonatal NMDA receptor subunit that is associated with hypoxia tolerance. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

LABORATORY EVALUATION OF ANDALIN, AN INSECT GROWTH REGULATOR INTERFERING WITH CUTICLE DEPOSITION, AGAINST MOSQUITO LARVAE

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N REHIMI

2002-12-01

Full Text Available Andalin, a benzoylphenylurea (BPU derivative, was evaluated on Culex pipiens L. (Diptera: Culicidae. Treatment was made on newly 3rd- and 4th instar larvae for 24 h. The compound exhibited insecticidal activity and mortality occured after earlier inhibition of their development or by their inability to complete their ecdysis. Treatment resulted in a significant larvicidal effect and in a inhibition of adult emergence. Moreover, the compound disturbed growth and development since several morphological types and an increase in the duration of larval stage were observed. Histological study conducted on 4th instar larval integument, showed that Andalin caused a significant reduction in the thickness of cuticles secreted compared to controls. Thus, Andalin prevent molting in C. pipiens by interfering with cuticle deposition confirming the primary mode of action of this BPU insecticide.

Productive performance of naked neck, frizzle and dwarf laying hens ...

African Journals Online (AJOL)

The productive performance of major genes for feather reduction (naked neck and frizzle) and body size reduction (dwarf) in a dual-purpose layer strain was evaluated in the subtropical coastal region of southeast Africa (Maputo, Mozambique). The experimental material consisted of ight different genetic groups, two diets ...

Multidimensional MRI-CT atlas of the naked mole-rat brain

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Fumiko eSeki

2013-12-01

Full Text Available Naked mole-rats have a variety of distinctive features such as the organisation of a hierarchical society (known as eusociality, extraordinary longevity, and cancer resistance; thus, it would be worthwhile investigating these animals in detail. One important task is the preparation of a brain atlas database that provide comprehensive information containing multidimensional data with various image contrasts, which can be achievable using a magnetic resonance imaging (MRI. Advanced MRI techniques such as diffusion tensor imaging (DTI, which generates high contrast images of fibre structures, can characterise unique morphological properties in addition to conventional MRI. To obtain high spatial resolution images, MR histology, DTI, and X-ray computed tomography (CT were performed on the fixed adult brain. Skull and brain structures were segmented as well as reconstructed in stereotaxic coordinates. Data were also acquired for the neonatal brain to allow developmental changes to be observed. Moreover, in vivo imaging of naked mole-rats was established as an evaluation tool of live animals. The data obtained comprised three-dimensional (3D images with high tissue contrast as well as stereotaxic coordinates. Developmental differences in the visual system were highlighted in particular by DTI. Although it was difficult to delineate optic nerves in the mature adult brain, parts of them could be distinguished in the immature neonatal brain. From observation of cortical thickness, possibility of high somatosensory system development replaced to the visual system was indicated. 3D visualisation of brain structures in the atlas as well as the establishment of in vivo imaging would promote neuroimaging researches towards detection of novel characteristics of eusocial naked mole-rats.

Analysis of expression and chitin-binding activity of the wing disc cuticle protein BmWCP4 in the silkworm, Bombyx mori.

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Deng, Hui-Min; Li, Yong; Zhang, Jia-Ling; Liu, Lin; Feng, Qi-Li

2016-12-01

The insect exoskeleton is mainly composed of chitin filaments linked by cuticle proteins. When insects molt, the cuticle of the exoskeleton is renewed by degrading the old chitin and cuticle proteins and synthesizing new ones. In this study, chitin-binding activity of the wing disc cuticle protein BmWCP4 in Bombyx mori was studied. Sequence analysis showed that the protein had a conservative hydrophilic "R&R" chitin-binding domain (CBD). Western blotting showed that BmWCP4 was predominately expressed in the wing disc-containing epidermis during the late wandering and early pupal stages. The immunohistochemistry result showed that the BmWCP4 was mainly present in the wing disc tissues containing wing bud and trachea blast during day 2 of wandering stage. Recombinant full-length BmWCP4 protein, "R&R" CBD peptide (CBD), non-CBD peptide (BmWCP4-CBD - ), four single site-directed mutated peptides (M 1 , M 2 , M 3 and M 4 ) and four-sites-mutated peptide (M F ) were generated and purified, respectively, for in vitro chitin-binding assay. The results indicated that both the full-length protein and the "R&R" CBD peptide could bind with chitin, whereas the BmWCP4-CBD - could not bind with chitin. The single residue mutants M 1 , M 2 , M 3 and M 4 reduced but did not completely abolish the chitin-binding activity, while four-sites-mutated protein M F completely lost the chitin-binding activity. These data indicate that BmWCP4 protein plays a critical role by binding to the chitin filaments in the wing during larva-to-pupa transformation. The conserved aromatic amino acids are critical in the interaction between chitin and the cuticle protein. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Investigation of the presence and antinociceptive function of muscarinic acetylcholine receptors in the African naked mole-rat (Heterocephalus glaber)

DEFF Research Database (Denmark)

Jørgensen, Kristine B.; Krogh-Jensen, Karen; Pickering, Darryl S

2016-01-01

The present study investigated the cholinergic system in the African naked mole-rat (Heterocephalus glaber) with focus on the muscarinic acetylcholine receptor subtypes M1 and M4. The protein sequences for the subtypes m 1–5 of the naked mole-rat were compared to that of the house mouse (Mus...... musculus) using basic local alignment search tool (BLAST). The presence and function of M1 and M4 was investigated in vivo, using the formalin test with the muscarinic receptor agonists xanomeline and VU0152100. Spinal cord tissue from the naked mole-rat was used for receptor saturation binding studies...

Disparate patterns of age-related changes in lipid peroxidation in long-lived naked mole-rats and shorter-lived mice.

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Andziak, Blazej; Buffenstein, Rochelle

2006-12-01

A key tenet of the oxidative stress theory of aging is that levels of accrued oxidative damage increase with age. Differences in damage generation and accumulation therefore may underlie the natural variation in species longevity. We compared age-related profiles of whole-organism lipid peroxidation (urinary isoprostanes) and liver lipid damage (malondialdehyde) in long living naked mole-rats [maximum lifespan (MLS) > 28.3 years] and shorter-living CB6F1 hybrid mice (MLS approximately 3.5 years). In addition, we compared age-associated changes in liver non-heme iron to assess how intracellular conditions, which may modulate oxidative processes, are affected by aging. Surprisingly, even at a young age, concentrations of both markers of lipid peroxidation, as well as of iron, were at least twofold (P naked mole tats than in mice. This refutes the hypothesis that prolonged naked mole-rat longevity is due to superior protection against oxidative stress. The age-related profiles of all three parameters were distinctly species specific. Rates of lipid damage generation in mice were maintained throughout adulthood, while accrued damage in old animals was twice that of young mice. In naked mole-rats, urinary isoprostane excretion declined by half with age (P naked mole-rats is independent of oxidative stress parameters.

TIM1 (HAVCR1 Is Not Essential for Cellular Entry of Either Quasi-enveloped or Naked Hepatitis A Virions

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Anshuman Das

2017-09-01

Full Text Available Receptor molecules play key roles in the cellular entry of picornaviruses, and TIM1 (HAVCR1 is widely accepted to be the receptor for hepatitis A virus (HAV, an unusual, hepatotropic human picornavirus. However, its identification as the hepatovirus receptor predated the discovery that hepatoviruses undergo nonlytic release from infected cells as membrane-cloaked, quasi-enveloped HAV (eHAV virions that enter cells via a pathway distinct from naked, nonenveloped virions. We thus revisited the role of TIM1 in hepatovirus entry, examining both adherence and infection/replication in cells with clustered regularly interspaced short palindromic repeat (CRISPR/Cas9-engineered TIM1 knockout. Cell culture-derived, gradient-purified eHAV bound Huh-7.5 human hepatoma cells less efficiently than naked HAV at 4°C, but eliminating TIM1 expression caused no difference in adherence of either form of HAV, nor any impact on infection and replication in these cells. In contrast, TIM1-deficient Vero cells showed a modest reduction in quasi-enveloped eHAV (but not naked HAV attachment and replication. Thus, TIM1 facilitates quasi-enveloped eHAV entry in Vero cells, most likely by binding phosphatidylserine (PtdSer residues on the eHAV membrane. Both Tim1−/− Ifnar1−/− and Tim4−/− Ifnar1−/− double-knockout mice were susceptible to infection upon intravenous challenge with infected liver homogenate, with fecal HAV shedding and serum alanine aminotransferase (ALT elevations similar to those in Ifnar1−/− mice. However, intrahepatic HAV RNA and ALT elevations were modestly reduced in Tim1−/−Ifnar1−/− mice compared to Ifnar1−/− mice challenged with a lower titer of gradient-purified HAV or eHAV. We conclude that TIM1 is not an essential hepatovirus entry factor, although its PtdSer-binding activity may contribute to the spread of quasi-enveloped virus and liver injury in mice.

Naked singularities in four-dimensional string backgrounds

International Nuclear Information System (INIS)

Mohammedi, N.

1993-04-01

It is shown that gauged nonlinear sigma models can be always deformed by terms proportional to the field strength of the gauge fields (nonminimal gauging). These deformations can be interpreted as perturbations, by marginal operators, of conformal coset models. When applied to the SL(2, R)xSU(2)/U(1)xU(1)) WZWN model, a large class of four-dimensional curved spacetime backgrounds are obtained. In particular, a naked singularity may form at a time when the volume of the universe is different from zero. (orig.)

Phage-mediated counting by the naked eye of miRNA molecules at attomolar concentrations in a Petri dish

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Zhou, Xin; Cao, Peng; Zhu, Ye; Lu, Wuguang; Gu, Ning; Mao, Chuanbin

2015-10-01

The ability to count biomolecules such as cancer-biomarker miRNAs with the naked eye is seemingly impossible in molecular diagnostics. Here, we show an ultrasensitive naked-eye-counting strategy for quantifying miRNAs by employing T7 phage--a bacteria-specific virus nanoparticle--as a surrogate. The phage is genetically engineered to become fluorescent and capable of binding a miRNA-capturing gold nanoparticle (GNP) in a one-to-one manner. Target miRNAs crosslink the resultant phage-GNP couple and miRNA-capturing magnetic microparticles, forming a sandwich complex containing equimolar phage and miRNA. The phage is then released from the complex and developed into one macroscopic fluorescent plaque in a Petri dish by plating it in a host bacterial medium. Counting the plaques by the naked eye enables the quantification of miRNAs with detection limits of ~3 and ~5 aM for single-target and two-target miRNAs, respectively. This approach offers ultrasensitive and convenient quantification of disease biomarkers by the naked eye.

The perception of (naked only) bodies and faceless heads relies on holistic processing: Evidence from the inversion effect.

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Bonemei, Rob; Costantino, Andrea I; Battistel, Ilenia; Rivolta, Davide

2018-05-01

Faces and bodies are more difficult to perceive when presented inverted than when presented upright (i.e., stimulus inversion effect), an effect that has been attributed to the disruption of holistic processing. The features that can trigger holistic processing in faces and bodies, however, still remain elusive. In this study, using a sequential matching task, we tested whether stimulus inversion affects various categories of visual stimuli: faces, faceless heads, faceless heads in body context, headless bodies naked, whole bodies naked, headless bodies clothed, and whole bodies clothed. Both accuracy and inversion efficiency score results show inversion effects for all categories but for clothed bodies (with and without heads). In addition, the magnitude of the inversion effect for face, naked body, and faceless heads was similar. Our findings demonstrate that the perception of faces, faceless heads, and naked bodies relies on holistic processing. Clothed bodies (with and without heads), on the other side, may trigger clothes-sensitive rather than body-sensitive perceptual mechanisms. © 2017 The British Psychological Society.

Naked mole-rat has increased translational fidelity compared with the mouse, as well as a unique 28S ribosomal RNA cleavage.

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Azpurua, Jorge; Ke, Zhonghe; Chen, Iris X; Zhang, Quanwei; Ermolenko, Dmitri N; Zhang, Zhengdong D; Gorbunova, Vera; Seluanov, Andrei

2013-10-22

The naked mole-rat (Heterocephalus glaber) is a subterranean eusocial rodent with a markedly long lifespan and resistance to tumorigenesis. Multiple data implicate modulation of protein translation in longevity. Here we report that 28S ribosomal RNA (rRNA) of the naked mole-rat is processed into two smaller fragments of unequal size. The two breakpoints are located in the 28S rRNA divergent region 6 and excise a fragment of 263 nt. The excised fragment is unique to the naked mole-rat rRNA and does not show homology to other genomic regions. Because this hidden break site could alter ribosome structure, we investigated whether translation rate and amino acid incorporation fidelity were altered. We report that naked mole-rat fibroblasts have significantly increased translational fidelity despite having comparable translation rates with mouse fibroblasts. Although we cannot directly test whether the unique 28S rRNA structure contributes to the increased fidelity of translation, we speculate that it may change the folding or dynamics of the large ribosomal subunit, altering the rate of GTP hydrolysis and/or interaction of the large subunit with tRNA during accommodation, thus affecting the fidelity of protein synthesis. In summary, our results show that naked mole-rat cells produce fewer aberrant proteins, supporting the hypothesis that the more stable proteome of the naked mole-rat contributes to its longevity.

Blunted behavioral and c Fos responses to acidic fumes in the African naked mole-rat.

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LaVinka, Pamela Colleen; Park, Thomas J

2012-01-01

Acidosis in the skin triggers activation of pain pathways and behaviors indicative of pain in vertebrates. The exception is the naked mole-rat, the only known vertebrate to show physiological and behavioral insensitivity to acid pain in the skin. The goal of the present study was to determine behavioral and physiological responses of this species to airborne acidic fumes, which would be expected to affect the trigeminal pain pathway in other species. Behaviorally, naked mole-rats did not avoid fumes from moderately high concentrations of acetic acid (10 and 20%), and c Fos labeling showed no increase in activity in the trigeminal nuclei and nucleus tractus solitarius. In contrast, these concentrations triggered behavioral aversion and increased Fos activity in other laboratory rodents. For a very high concentration of acetic acid (50%), naked mole-rats showed significant avoidance behavior and increased Fos labeling in the nucleus tractus solitarius caudal region, which receives vagal chemosensory information. However, there was no increase in trigeminal labeling, and in fact, activity significantly decreased. This pattern is opposite of that associated with another irritant, ammonia fumes, which elicited an increase in trigeminal but not nucleus tractus solitarius Fos labeling, and no behavioral avoidance. Behavioral avoidance of acidic fumes, but no increased labeling in the trigeminal pain nucleus is consistent with the notion of adaptations to blunt acid pain, which would be advantageous for naked mole-rats as they normally live under chronically high levels of acidosis-inducing CO(2).

Blunted behavioral and c Fos responses to acidic fumes in the African naked mole-rat.

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Pamela Colleen LaVinka

Full Text Available Acidosis in the skin triggers activation of pain pathways and behaviors indicative of pain in vertebrates. The exception is the naked mole-rat, the only known vertebrate to show physiological and behavioral insensitivity to acid pain in the skin. The goal of the present study was to determine behavioral and physiological responses of this species to airborne acidic fumes, which would be expected to affect the trigeminal pain pathway in other species. Behaviorally, naked mole-rats did not avoid fumes from moderately high concentrations of acetic acid (10 and 20%, and c Fos labeling showed no increase in activity in the trigeminal nuclei and nucleus tractus solitarius. In contrast, these concentrations triggered behavioral aversion and increased Fos activity in other laboratory rodents. For a very high concentration of acetic acid (50%, naked mole-rats showed significant avoidance behavior and increased Fos labeling in the nucleus tractus solitarius caudal region, which receives vagal chemosensory information. However, there was no increase in trigeminal labeling, and in fact, activity significantly decreased. This pattern is opposite of that associated with another irritant, ammonia fumes, which elicited an increase in trigeminal but not nucleus tractus solitarius Fos labeling, and no behavioral avoidance. Behavioral avoidance of acidic fumes, but no increased labeling in the trigeminal pain nucleus is consistent with the notion of adaptations to blunt acid pain, which would be advantageous for naked mole-rats as they normally live under chronically high levels of acidosis-inducing CO(2.

Detection of irradiation in cuticles of commercial shrimps

International Nuclear Information System (INIS)

Lehner, K.; Stachowicz, W.

2006-01-01

Laboratory for Detection of Irradiated Food has more and more orders for detection of irradiation in shrimps. A method adapted to achieve detection of irradiation in this material is a thermoluminescence measure. However, the procedure is time-consuming - needs several days to receive the result. The aim of presented study was to elaborate the EPR examination of the possible irradiation in this product. As a result od the performed studies it can be concluded, that the EPR measurement of cuticles of shrimps can be adapted as the preliminary, screening test proving the irradiation of shrimp. It has to be stressed, however, that the lack of a specific, hydroxyapatite born EPR signal in the spectrum cannot suggest that sample was not irradiated

Characterization of a plant leaf cuticle model wax, phase behaviour of model wax–water systems

International Nuclear Information System (INIS)

Fagerström, Anton; Kocherbitov, Vitaly; Westbye, Peter; Bergström, Karin; Mamontova, Varvara; Engblom, Johan

2013-01-01

Highlights: • Four individual crystalline phases were discovered in the model wax–water system. • Eutectic melting occurred in both dry and hydrated model wax. • The total transition enthalpy is smaller for the cuticle wax than for the model wax. • Water has a large plasticizing effect on cuticle wax. • The thermotropic transitions of model wax fit in the window of extracted leaf waxes. - Abstract: We investigated the thermotropic phase behaviour of plant leaf intracuticular wax and two representatives of its main components, 1-docosanol (C 22 H 45 OH) and dotriacontane (C 32 H 66 ), in dry and hydrated state. One objective was to obtain a model wax, which can be used to estimate formulations effects on cuticle diffusivity in vitro. The two wax components were chosen based on results from Gas Chromatography coupled to Mass Spectrometry analysis of cuticular wax. The wax was extracted from Clivia Miniata Regel leaves and contained 68% primary alcohols (C 16 –C 32 ) and 16% n-alkanes (C 21 –C 33 ). Differential Scanning Calorimetry, Polarized Light Microscopy and Small- and Wide Angle X-ray Diffraction were used to characterize the cuticular extract and the phase behaviour of the C 22 H 45 OH/C 32 H 66 /H 2 O model system. Four individual crystalline phases were discovered in the model wax–water system and eutectic melting occurred in both dry and hydrated state. The thermotropic transitions of the model wax occur within the broader transition region of the extracted leaf wax

Regulation of C. elegans L4 cuticle collagen genes by the heterochronic protein LIN-29.

Science.gov (United States)

Abete-Luzi, Patricia; Eisenmann, David M

2018-05-01

The cuticle, the outer covering of the nematode C. elegans, is synthesized five times during the worm's life by the underlying hypodermis. Cuticle collagens, the major cuticle component, are encoded by a large family of col genes and, interestingly, many of these genes express predominantly at a single developmental stage. This temporal preference motivated us to investigate the mechanisms underlying col gene expression and here we focus on a subset of col genes expressed in the L4 stage. We identified minimal promoter regions of <300 bp for col-38, col-49, and col-63. In these regions, we predicted cis-regulatory sequences and evaluated their function in vivo via mutagenesis of a col-38p::yfp reporter. We used RNAi to study the requirement for candidate transcription regulators ELT-1 and ELT-3, LIN-29, and the LIN-29 co-factor MAB-10, and found LIN-29 to be necessary for the expression of four L4-specific genes (col-38, col-49, col-63, and col-138). Temporal misexpression of LIN-29 was also sufficient to activate these genes at a different developmental stage. The LIN-29 DNA-binding domain bound the col-38, col-49, and col-63 minimal promoters in vitro. For col-38 we showed that the LIN-29 sites necessary for reporter expression in vivo are also bound in vitro: this is the first identification of specific binding sites for LIN-29 necessary for in vivo target gene expression. © 2018 Wiley Periodicals, Inc.

"All in the Day's Work": Cold War Doctoring and Its Discontents in William Burroughs's Naked Lunch.

Science.gov (United States)

Jarvis, Michael

In Naked Lunch, the institutions and practices of science and medicine, specifically with regard to psychiatry/psychology, are symptoms of a bureaucratic system of control that shapes, constructs, defines, and makes procrustean alterations to both the mind and body of human subjects. Using sickness and junk (or heroin) as convenient metaphors for both a Cold War binary mentality and the mandatory consumption of twentieth-century capitalism, Burroughs presents modern man as fundamentally alienated from any sense of a personal self. Through policing the health of citizens, the doctors are some of the novel's most overt "Senders," or agents of capital-C Control, commodifying and exploiting the individual's humanity (mind and body) as a raw material in the generation of a knowledge that functions only in the legitimation and reinforcement of itself as authoritative.

Cuticle deposition in imaginal disks: effects of juvenile hormone and fat body in vitro.

Science.gov (United States)

Oberlander, H; Tomblin, C

1972-08-04

Wing disks from the last larval instar of the Indian meal moth, Plodia interpunctella (Hübner), were successfully cultured in modified Grace's medium. 20-Hydroxyecdysone induced cuticle deposition in these disks in vitro. This response was enhanced by treating the medium with larval fat body and was inhibited by application of juvenile hormone.

Direct surface analysis coupled to high-resolution mass spectrometry reveals heterogeneous composition of the cuticle of Hibiscus trionum petals.

Science.gov (United States)

Giorio, Chiara; Moyroud, Edwige; Glover, Beverley J; Skelton, Paul C; Kalberer, Markus

2015-10-06

Plant cuticle, which is the outermost layer covering the aerial parts of all plants including petals and leaves, can present a wide range of patterns that, combined with cell shape, can generate unique physical, mechanical, or optical properties. For example, arrays of regularly spaced nanoridges have been found on the dark (anthocyanin-rich) portion at the base of the petals of Hibiscus trionum. Those ridges act as a diffraction grating, producing an iridescent effect. Because the surface of the distal white region of the petals is smooth and noniridescent, a selective chemical characterization of the surface of the petals on different portions (i.e., ridged vs smooth) is needed to understand whether distinct cuticular patterns correlate with distinct chemical compositions of the cuticle. In the present study, a rapid screening method has been developed for the direct surface analysis of Hibiscus trionum petals using liquid extraction surface analysis (LESA) coupled with high-resolution mass spectrometry. The optimized method was used to characterize a wide range of plant metabolites and cuticle monomers on the upper (adaxial) surface of the petals on both the white/smooth and anthocyanic/ridged regions, and on the lower (abaxial) surface, which is entirely smooth. The main components detected on the surface of the petals are low-molecular-weight organic acids, sugars, and flavonoids. The ridged portion on the upper surface of the petal is enriched in long-chain fatty acids, which are constituents of the wax fraction of the cuticle. These compounds were not detected on the white/smooth region of the upper petal surface or on the smooth lower surface.

Circular geodesics of naked singularities in the Kehagias-Sfetsos metric of Hořava's gravity

Science.gov (United States)

Vieira, Ronaldo S. S.; Schee, Jan; Kluźniak, Włodek; Stuchlík, Zdeněk; Abramowicz, Marek

2014-07-01

We discuss photon and test-particle orbits in the Kehagias-Sfetsos (KS) metric of Hořava's gravity. For any value of the Hořava parameter ω, there are values of the gravitational mass M for which the metric describes a naked singularity, and this is always accompanied by a vacuum "antigravity sphere" on whose surface a test particle can remain at rest (in a zero angular momentum geodesic), and inside which no circular geodesics exist. The observational appearance of an accreting KS naked singularity in a binary system would be that of a quasistatic spherical fluid shell surrounded by an accretion disk, whose properties depend on the value of M, but are always very different from accretion disks familiar from the Kerr-metric solutions. The properties of the corresponding circular orbits are qualitatively similar to those of the Reissner-Nordström naked singularities. When event horizons are present, the orbits outside the Kehagias-Sfetsos black hole are qualitatively similar to those of the Schwarzschild metric.

TIM1 (HAVCR1) Is Not Essential for Cellular Entry of Either Quasi-enveloped or Naked Hepatitis A Virions.

Science.gov (United States)

Das, Anshuman; Hirai-Yuki, Asuka; González-López, Olga; Rhein, Bethany; Moller-Tank, Sven; Brouillette, Rachel; Hensley, Lucinda; Misumi, Ichiro; Lovell, William; Cullen, John M; Whitmire, Jason K; Maury, Wendy; Lemon, Stanley M

2017-09-05

Receptor molecules play key roles in the cellular entry of picornaviruses, and TIM1 (HAVCR1) is widely accepted to be the receptor for hepatitis A virus (HAV), an unusual, hepatotropic human picornavirus. However, its identification as the hepatovirus receptor predated the discovery that hepatoviruses undergo nonlytic release from infected cells as membrane-cloaked, quasi-enveloped HAV (eHAV) virions that enter cells via a pathway distinct from naked, nonenveloped virions. We thus revisited the role of TIM1 in hepatovirus entry, examining both adherence and infection/replication in cells with clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-engineered TIM1 knockout. Cell culture-derived, gradient-purified eHAV bound Huh-7.5 human hepatoma cells less efficiently than naked HAV at 4°C, but eliminating TIM1 expression caused no difference in adherence of either form of HAV, nor any impact on infection and replication in these cells. In contrast, TIM1-deficient Vero cells showed a modest reduction in quasi-enveloped eHAV (but not naked HAV) attachment and replication. Thus, TIM1 facilitates quasi-enveloped eHAV entry in Vero cells, most likely by binding phosphatidylserine (PtdSer) residues on the eHAV membrane. Both Tim1 -/- Ifnar1 -/- and Tim4 -/- Ifnar1 -/- double-knockout mice were susceptible to infection upon intravenous challenge with infected liver homogenate, with fecal HAV shedding and serum alanine aminotransferase (ALT) elevations similar to those in Ifnar1 -/- mice. However, intrahepatic HAV RNA and ALT elevations were modestly reduced in Tim1 -/- Ifnar1 -/- mice compared to Ifnar1 -/- mice challenged with a lower titer of gradient-purified HAV or eHAV. We conclude that TIM1 is not an essential hepatovirus entry factor, although its PtdSer-binding activity may contribute to the spread of quasi-enveloped virus and liver injury in mice. IMPORTANCE T cell immunoglobulin and mucin-containing domain protein 1 (TIM1) was reported more than

The effect of processing treatments on the radiation-induced ESR signal in the cuticle of irradiated Norway lobster (Nephrops norvegicus)

International Nuclear Information System (INIS)

Stewart, E.M.; Stevenson, M.H.; Gray, R.; McMurray, C.H.

1993-01-01

Cooked, frozen or chilled whole tails of Norway lobster were either not irradiated or given doses of 1, 2, 3, 4 or 5 kGy using cobalt 60 source. The cuticle was removed, freeze-dried and ground before determination of the free radical concentration using electron spin resonance (ESR) spectroscopy. The ESR signal strength increased linearly with increasing irradiation dose. In comparison to the chilled samples, cooking before irradiation significantly increased (69%) signal intensity whereas cooking after irradiation decreased (27%) signal strength. Irradiating the samples in the frozen state did not significantly alter the free radical concentration in the cuticle. (author)

Characterization of a plant leaf cuticle model wax, phase behaviour of model wax–water systems

Energy Technology Data Exchange (ETDEWEB)

Fagerström, Anton, E-mail: anton.fagerstrom@mah.se [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden); Kocherbitov, Vitaly [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden); Westbye, Peter; Bergström, Karin [Agro Applications Europe, AkzoNobel Surface Chemistry AB, Stenungsund (Sweden); Mamontova, Varvara [Ecological and Chemical Research, St. Petersburg Scientific Research Center for Ecological Safety, Russian Academy of Sciences, St. Petersburg (Russian Federation); Engblom, Johan [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden)

2013-11-10

Highlights: • Four individual crystalline phases were discovered in the model wax–water system. • Eutectic melting occurred in both dry and hydrated model wax. • The total transition enthalpy is smaller for the cuticle wax than for the model wax. • Water has a large plasticizing effect on cuticle wax. • The thermotropic transitions of model wax fit in the window of extracted leaf waxes. - Abstract: We investigated the thermotropic phase behaviour of plant leaf intracuticular wax and two representatives of its main components, 1-docosanol (C{sub 22}H{sub 45}OH) and dotriacontane (C{sub 32}H{sub 66}), in dry and hydrated state. One objective was to obtain a model wax, which can be used to estimate formulations effects on cuticle diffusivity in vitro. The two wax components were chosen based on results from Gas Chromatography coupled to Mass Spectrometry analysis of cuticular wax. The wax was extracted from Clivia Miniata Regel leaves and contained 68% primary alcohols (C{sub 16}–C{sub 32}) and 16% n-alkanes (C{sub 21}–C{sub 33}). Differential Scanning Calorimetry, Polarized Light Microscopy and Small- and Wide Angle X-ray Diffraction were used to characterize the cuticular extract and the phase behaviour of the C{sub 22}H{sub 45}OH/C{sub 32}H{sub 66}/H{sub 2}O model system. Four individual crystalline phases were discovered in the model wax–water system and eutectic melting occurred in both dry and hydrated state. The thermotropic transitions of the model wax occur within the broader transition region of the extracted leaf wax.

Seasonal abundances of naked amoebae in biofilms on shells of zebra mussels (Dreissena polymorpha) with comparative data from rock scrapings.

Science.gov (United States)

Bischoff, Paul J; Wetmore, Scott

2009-01-01

In North America, zebra mussels (Dreissena polymorpha) are notoriously known as invasive species. The abundance of naked amoebae sampled from the shells of zebra mussels was compared with abundances from rock scrapings at approximately monthly intervals for 1 year. The sites were 2 km apart along the same shoreline. No significant difference in abundance of naked amoebae (F = 1.44; P naked amoebae in winter, followed by peaks in early spring. The percent encysted increased from a low of 1% in the summer to 80% in early winter.

Functional neurokinin and NMDA receptor activity in an animal naturally lacking substance P: the naked mole-rat.

Directory of Open Access Journals (Sweden)

Antje Brand

Full Text Available Naked mole-rats are extremely unusual among mammals in that their cutaneous C-fibers lack the neuropeptide Substance P (SP. In other mammals, SP plays an important role in nociception: it is released from C-fibers onto spinal neurons where it facilitates NMDA receptor activity and causes sensitization that can last for minutes, hours or days. In the present study, we tested the effects of intrathecal application of: 1 SP, 2 an SP antagonist (GR-82334, and 3 an NMDA antagonist (APV on heat-evoked foot withdrawal. In the naked mole-rat, at a high enough concentration, application of SP caused a large, immediate, and long-lasting sensitization of foot withdrawal latency that was transiently reversed by application of either antagonist. However, neither SP nor NMDA antagonists had an effect when administered alone to naïve animals. In contrast, both antagonists induced an increase in basal withdrawal latency in mice. These results indicate that spinal neurons in naked mole-rats have functional SP and NMDA receptors, but that these receptors do not participate in heat-evoked foot withdrawal unless SP is experimentally introduced. We propose that the natural lack of SP in naked mole-rat C-fibers may have resulted during adaptation to living in a chronically high carbon dioxide, high ammonia environment that, in other mammals, would stimulate C-fibers and evoke nocifensive behavior.

Functional neurokinin and NMDA receptor activity in an animal naturally lacking substance P: the naked mole-rat.

Science.gov (United States)

Brand, Antje; Smith, Ewan St J; Lewin, Gary R; Park, Thomas J

2010-12-21

Naked mole-rats are extremely unusual among mammals in that their cutaneous C-fibers lack the neuropeptide Substance P (SP). In other mammals, SP plays an important role in nociception: it is released from C-fibers onto spinal neurons where it facilitates NMDA receptor activity and causes sensitization that can last for minutes, hours or days. In the present study, we tested the effects of intrathecal application of: 1) SP, 2) an SP antagonist (GR-82334), and 3) an NMDA antagonist (APV) on heat-evoked foot withdrawal. In the naked mole-rat, at a high enough concentration, application of SP caused a large, immediate, and long-lasting sensitization of foot withdrawal latency that was transiently reversed by application of either antagonist. However, neither SP nor NMDA antagonists had an effect when administered alone to naïve animals. In contrast, both antagonists induced an increase in basal withdrawal latency in mice. These results indicate that spinal neurons in naked mole-rats have functional SP and NMDA receptors, but that these receptors do not participate in heat-evoked foot withdrawal unless SP is experimentally introduced. We propose that the natural lack of SP in naked mole-rat C-fibers may have resulted during adaptation to living in a chronically high carbon dioxide, high ammonia environment that, in other mammals, would stimulate C-fibers and evoke nocifensive behavior.

The Dual Role of an ESCRT-0 Component HGS in HBV Transcription and Naked Capsid Secretion.

Directory of Open Access Journals (Sweden)

Shu-Fan Chou

2015-10-01

Full Text Available The Endosomal Sorting Complex Required for Transport (ESCRT is an important cellular machinery for the sorting and trafficking of ubiquitinated cargos. It is also known that ESCRT is required for the egress of a number of viruses. To investigate the relationship between ESCRT and hepatitis B virus (HBV, we conducted an siRNA screening of ESCRT components for their potential effect on HBV replication and virion release. We identified a number of ESCRT factors required for HBV replication, and focused our study here on HGS (HRS, hepatocyte growth factor-regulated tyrosine kinase substrate in the ESCRT-0 complex. Aberrant levels of HGS suppressed HBV transcription, replication and virion secretion. Hydrodynamic delivery of HGS in a mouse model significantly suppressed viral replication in the liver and virion secretion in the serum. Surprisingly, overexpression of HGS stimulated the release of HBV naked capsids, irrespective of their viral RNA, DNA, or empty contents. Mutant core protein (HBc 1-147 containing no arginine-rich domain (ARD failed to secrete empty virions with or without HGS. In contrast, empty naked capsids of HBc 1-147 could still be promoted for secretion by HGS. HGS exerted a strong positive effect on the secretion of naked capsids, at the expense of a reduced level of virions. The association between HGS and HBc appears to be ubiquitin-independent. Furthermore, HBc is preferentially co-localized with HGS near the cell periphery, instead of near the punctate endosomes in the cytoplasm. In summary, our work demonstrated the importance of an optimum level of HGS in HBV propagation. In addition to an effect on HBV transcription, HGS can diminish the pool size of intracellular nucleocapsids with ongoing genome maturation, probably in part by promoting the secretion of naked capsids. The secretion routes of HBV virions and naked capsids can be clearly distinguished based on the pleiotropic effect of HGS involved in the ESCRT-0 complex.

The Dual Role of an ESCRT-0 Component HGS in HBV Transcription and Naked Capsid Secretion

Science.gov (United States)

Chou, Shu-Fan; Tsai, Ming-Lin; Huang, Jyun-Yuan; Chang, Ya-Shu; Shih, Chiaho

2015-01-01

The Endosomal Sorting Complex Required for Transport (ESCRT) is an important cellular machinery for the sorting and trafficking of ubiquitinated cargos. It is also known that ESCRT is required for the egress of a number of viruses. To investigate the relationship between ESCRT and hepatitis B virus (HBV), we conducted an siRNA screening of ESCRT components for their potential effect on HBV replication and virion release. We identified a number of ESCRT factors required for HBV replication, and focused our study here on HGS (HRS, hepatocyte growth factor-regulated tyrosine kinase substrate) in the ESCRT-0 complex. Aberrant levels of HGS suppressed HBV transcription, replication and virion secretion. Hydrodynamic delivery of HGS in a mouse model significantly suppressed viral replication in the liver and virion secretion in the serum. Surprisingly, overexpression of HGS stimulated the release of HBV naked capsids, irrespective of their viral RNA, DNA, or empty contents. Mutant core protein (HBc 1–147) containing no arginine-rich domain (ARD) failed to secrete empty virions with or without HGS. In contrast, empty naked capsids of HBc 1–147 could still be promoted for secretion by HGS. HGS exerted a strong positive effect on the secretion of naked capsids, at the expense of a reduced level of virions. The association between HGS and HBc appears to be ubiquitin-independent. Furthermore, HBc is preferentially co-localized with HGS near the cell periphery, instead of near the punctate endosomes in the cytoplasm. In summary, our work demonstrated the importance of an optimum level of HGS in HBV propagation. In addition to an effect on HBV transcription, HGS can diminish the pool size of intracellular nucleocapsids with ongoing genome maturation, probably in part by promoting the secretion of naked capsids. The secretion routes of HBV virions and naked capsids can be clearly distinguished based on the pleiotropic effect of HGS involved in the ESCRT-0 complex. PMID

Soil water stress affects both cuticular wax content and cuticle-related gene expression in young saplings of maritime pine (Pinus pinaster Ait).

Science.gov (United States)

Le Provost, Grégoire; Domergue, Frédéric; Lalanne, Céline; Ramos Campos, Patricio; Grosbois, Antoine; Bert, Didier; Meredieu, Céline; Danjon, Frédéric; Plomion, Christophe; Gion, Jean-Marc

2013-07-01

The cuticle is a hydrophobic barrier located at the aerial surface of all terrestrial plants. Recent studies performed on model plants, such as Arabidopsis thaliana, have suggested that the cuticle may be involved in drought stress adaptation, preventing non-stomatal water loss. Although forest trees will face more intense drought stresses (in duration and intensity) with global warming, very few studies on the role of the cuticle in drought stress adaptation in these long-lived organisms have been so far reported. This aspect was investigated in a conifer, maritime pine (Pinus pinaster Ait.), in a factorial design with two genetic units (two half-sib families with different growth rates) and two treatments (irrigated vs non-irrigated), in field conditions. Saplings were grown in an open-sided greenhouse and half were irrigated three times per week for two growing seasons. Needles were sampled three times per year for cuticular wax (composition and content) and transcriptome (of 11 genes involved in cuticle biosynthesis) analysis. Non-irrigated saplings (i) had a higher cuticular wax content than irrigated saplings and (ii) overexpressed most of the genes studied. Both these trends were more marked in the faster growing family. The higher cuticular wax content observed in the non-irrigated treatment associated with strong modifications in products from the decarbonylation pathway suggest that cuticular wax may be involved in drought stress adaptation in maritime pine. This study provides also a set of promising candidate genes for future forward genetic studies in conifers.

effects of naked-neck and frizzle genes on growth performance and ...

African Journals Online (AJOL)

User

cockerels (birds) do not reach their full genetic potential in terms of growth, body weight or carcass yields because their feathers hinder the dissipation of their excessively produced inter- nal heat. It is against this background that the use of major heat-tolerant genes like naked- neck and frizzle is advocated (Horst and.

Functional characteristics of the naked mole rat μ-opioid receptor.

Directory of Open Access Journals (Sweden)

Melanie Busch-Dienstfertig

Full Text Available While humans and most animals respond to µ-opioid receptor (MOR agonists with analgesia and decreased aggression, in the naked mole rat (NMR opioids induce hyperalgesia and severe aggression. Single nucleotide polymorphisms in the human mu-opioid receptor gene (OPRM1 can underlie altered behavioral responses to opioids. Therefore, we hypothesized that the primary structure of the NMR MOR may differ from other species. Sequencing of the NMR oprm1 revealed strong homology to other mammals, but exposed three unique amino acids that might affect receptor-ligand interactions. The NMR and rat oprm1 sequences were cloned into mammalian expression vectors and transfected into HEK293 cells. Radioligand binding and 3'-5'-cyclic adenosine monophosphate (cAMP enzyme immunoassays were used to compare opioid binding and opioid-mediated cAMP inhibition. At normalized opioid receptor protein levels we detected significantly lower [3H]DAMGO binding to NMR compared to rat MOR, but no significant difference in DAMGO-induced cAMP inhibition. Strong DAMGO-induced MOR internalization was detectable using radioligand binding and confocal imaging in HEK293 cells expressing rat or NMR receptor, while morphine showed weak or no effects. In summary, we found minor functional differences between rat and NMR MOR suggesting that other differences e.g. in anatomical distribution of MOR underlie the NMR's extreme reaction to opioids.

Naked singularities are not singular in distorted gravity

Energy Technology Data Exchange (ETDEWEB)

Garattini, Remo, E-mail: Remo.Garattini@unibg.it [Università degli Studi di Bergamo, Facoltà di Ingegneria, Viale Marconi 5, 24044 Dalmine (Bergamo) (Italy); I.N.F.N. – sezione di Milano, Milan (Italy); Majumder, Barun, E-mail: barunbasanta@iitgn.ac.in [Indian Institute of Technology Gandhinagar, Ahmedabad, Gujarat 382424 (India)

2014-07-15

We compute the Zero Point Energy (ZPE) induced by a naked singularity with the help of a reformulation of the Wheeler–DeWitt equation. A variational approach is used for the calculation with Gaussian Trial Wave Functionals. The one loop contribution of the graviton to the ZPE is extracted keeping under control the UltraViolet divergences by means of a distorted gravitational field. Two examples of distortion are taken under consideration: Gravity's Rainbow and Noncommutative Geometry. Surprisingly, we find that the ZPE is no more singular when we approach the singularity.

Naked singularities are not singular in distorted gravity

Science.gov (United States)

Garattini, Remo; Majumder, Barun

2014-07-01

We compute the Zero Point Energy (ZPE) induced by a naked singularity with the help of a reformulation of the Wheele-DeWitt equation. A variational approach is used for the calculation with Gaussian Trial Wave Functionals. The one loop contribution of the graviton to the ZPE is extracted keeping under control the UltraViolet divergences by means of a distorted gravitational field. Two examples of distortion are taken under consideration: Gravity's Rainbow and Noncommutative Geometry. Surprisingly, we find that the ZPE is no more singular when we approach the singularity.

Naked singularities are not singular in distorted gravity

International Nuclear Information System (INIS)

Garattini, Remo; Majumder, Barun

2014-01-01

We compute the Zero Point Energy (ZPE) induced by a naked singularity with the help of a reformulation of the Wheeler–DeWitt equation. A variational approach is used for the calculation with Gaussian Trial Wave Functionals. The one loop contribution of the graviton to the ZPE is extracted keeping under control the UltraViolet divergences by means of a distorted gravitational field. Two examples of distortion are taken under consideration: Gravity's Rainbow and Noncommutative Geometry. Surprisingly, we find that the ZPE is no more singular when we approach the singularity

Oviposition and egg quality traits of dwarf and naked neck layers ...

African Journals Online (AJOL)

Oviposition and egg quality traits were studied in dwarf and naked neck layers in Maputo (Mozambique) during a 28-d period at 35 weeks of age. Birds were caged individually in a laying house with natural light and ventilation. Average daylight length during the study was 11.2 hr and minimum and maximum temperature ...

case of natural queen succession in a captive colony of naked mole ...

African Journals Online (AJOL)

Naked mole-rats occur in large colonies where usually a single queen monopolizes reproduction. Queen succession occurs from within usually as a result of aggressive encounters with subordinate females that queue for reproductive succession following colony instability, which inevitably results in death of either the ...

Darker eggs of mosquitoes resist more to dry conditions: Melanin enhances serosal cuticle contribution in egg resistance to desiccation in Aedes, Anopheles and Culex vectors.

Science.gov (United States)

Farnesi, Luana C; Vargas, Helena C M; Valle, Denise; Rezende, Gustavo L

2017-10-01

Mosquito vectors lay their white eggs in the aquatic milieu. During early embryogenesis water passes freely through the transparent eggshell, which at this moment is composed of exochorion and endochorion. Within two hours the endochorion darkens via melanization but even so eggs shrink and perish if removed from moisture. However, during mid-embryogenesis, cells of the extraembryonic serosa secrete the serosal cuticle, localized right below the endochorion, becoming the third and innermost eggshell layer. Serosal cuticle formation greatly reduces water flow and allows egg survival outside the water. The degree of egg resistance to desiccation (ERD) at late embryogenesis varies among different species: Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus eggs can survive in a dry environment for ≥ 72, 24 and 5 hours, respectively. In some adult insects, darker-body individuals show greater resistance to desiccation than lighter ones. We asked if egg melanization enhances mosquito serosal cuticle-dependent ERD. Species with higher ERD at late embryogenesis exhibit more melanized eggshells. The melanization-ERD hypothesis was confirmed employing two Anopheles quadrimaculatus strains, the wild type and the mutant GORO, with a dark-brown and a golden eggshell, respectively. In all cases, serosal cuticle formation is fundamental for the establishment of an efficient ERD but egg viability outside the water is much higher in mosquitoes with darker eggshells than in those with lighter ones. The finding that pigmentation influences egg water balance is relevant to understand the evolutionary history of insect egg coloration. Since eggshell and adult cuticle pigmentation ensure insect survivorship in some cases, they should be considered regarding species fitness and novel approaches for vector or pest insects control.

Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia

Directory of Open Access Journals (Sweden)

Philip G. Cox

2014-06-01

Full Text Available The naked mole-rat, Heterocephalus glaber, of the family Bathyergidae is a subterranean rodent that feeds on underground roots and tubers and digs extensive tunnel systems with its incisors. It is a highly unusual mammal with regard to its social structure, longevity, pain insensitivity and cancer resistance, all of which have made it the subject of a great deal of research in recent years. Yet, much of the basic anatomy of this species remains undocumented. In this paper, we describe the morphology of the jaw-closing musculature of the naked mole-rat, as revealed by contrast-enhanced micro-computed tomography. This technique uses an iodine stain to enable the imaging of soft tissues with microCT. The iodine-enhanced scans were used to create 3D reconstructions of the naked mole-rat masticatory muscles from which muscle masses were calculated. The jaw-closing musculature of Heterocephalus glaber is relatively very large compared to other rodents and is dominated by the superficial masseter, the deep masseter and the temporalis. The temporalis in particular is large for a rodent, covering the entirety of the braincase and much of the rear part of the orbit. The morphology of the masseter complex described here differs from two other published descriptions of bathyergid masticatory muscles, but is more similar to the arrangement seen in other rodent families. The zygomaticomandibularis (ZM muscle does not protrude through the infraorbital foramen on to the rostrum and thus the naked mole-rat should be considered protrogomorphous rather than hystricomorphous, and the morphology is consistent with secondarily lost hystricomorphy as has been previously suggested for Bathyergidae. Overall, the morphology of the masticatory musculature indicates a species with a high bite force and a wide gape–both important adaptations for a life dominated by digging with the incisors.

Multidimensional MRI-CT atlas of the naked mole-rat brain (Heterocephalus glaber).

Science.gov (United States)

Seki, Fumiko; Hikishima, Keigo; Nambu, Sanae; Okanoya, Kazuo; Okano, Hirotaka J; Sasaki, Erika; Miura, Kyoko; Okano, Hideyuki

2013-01-01

Naked mole-rats have a variety of distinctive features such as the organization of a hierarchical society (known as eusociality), extraordinary longevity, and cancer resistance; thus, it would be worthwhile investigating these animals in detail. One important task is the preparation of a brain atlas database that provide comprehensive information containing multidimensional data with various image contrasts, which can be achievable using a magnetic resonance imaging (MRI). Advanced MRI techniques such as diffusion tensor imaging (DTI), which generates high contrast images of fiber structures, can characterize unique morphological properties in addition to conventional MRI. To obtain high spatial resolution images, MR histology, DTI, and X-ray computed tomography were performed on the fixed adult brain. Skull and brain structures were segmented as well as reconstructed in stereotaxic coordinates. Data were also acquired for the neonatal brain to allow developmental changes to be observed. Moreover, in vivo imaging of naked mole-rats was established as an evaluation tool of live animals. The data obtained comprised three-dimensional (3D) images with high tissue contrast as well as stereotaxic coordinates. Developmental differences in the visual system were highlighted in particular by DTI. Although it was difficult to delineate optic nerves in the mature adult brain, parts of them could be distinguished in the immature neonatal brain. From observation of cortical thickness, possibility of high somatosensory system development replaced to the visual system was indicated. 3D visualization of brain structures in the atlas as well as the establishment of in vivo imaging would promote neuroimaging researches towards detection of novel characteristics of eusocial naked mole-rats.

Altered composition of liver proteasome assemblies contributes to enhanced proteasome activity in the exceptionally long-lived naked mole-rat.

Science.gov (United States)

Rodriguez, Karl A; Edrey, Yael H; Osmulski, Pawel; Gaczynska, Maria; Buffenstein, Rochelle

2012-01-01

The longest-lived rodent, the naked mole-rat (Bathyergidae; Heterocephalus glaber), maintains robust health for at least 75% of its 32 year lifespan, suggesting that the decline in genomic integrity or protein homeostasis routinely observed during aging, is either attenuated or delayed in this extraordinarily long-lived species. The ubiquitin proteasome system (UPS) plays an integral role in protein homeostasis by degrading oxidatively-damaged and misfolded proteins. In this study, we examined proteasome activity in naked mole-rats and mice in whole liver lysates as well as three subcellular fractions to probe the mechanisms behind the apparently enhanced effectiveness of UPS. We found that when compared with mouse samples, naked mole-rats had significantly higher chymotrypsin-like (ChT-L) activity and a two-fold increase in trypsin-like (T-L) in both whole lysates as well as cytosolic fractions. Native gel electrophoresis of the whole tissue lysates showed that the 20S proteasome was more active in the longer-lived species and that 26S proteasome was both more active and more populous. Western blot analyses revealed that both 19S subunits and immunoproteasome catalytic subunits are present in greater amounts in the naked mole-rat suggesting that the observed higher specific activity may be due to the greater proportion of immunoproteasomes in livers of healthy young adults. It thus appears that proteasomes in this species are primed for the efficient removal of stress-damaged proteins. Further characterization of the naked mole-rat proteasome and its regulation could lead to important insights on how the cells in these animals handle increased stress and protein damage to maintain a longer health in their tissues and ultimately a longer life.

Challenging the inbreeding hypothesis in a eusocial mammal: population genetics of the naked mole-rat, Heterocephalus glaber.

Science.gov (United States)

Ingram, Colleen M; Troendle, Nicholas J; Gill, Clare A; Braude, Stanton; Honeycutt, Rodney L

2015-10-01

The role of genetic relatedness in the evolution of eusociality has been the topic of much debate, especially when contrasting eusocial insects with vertebrates displaying reproductive altruism. The naked mole-rat, Heterocephalus glaber, was the first described eusocial mammal. Although this discovery was based on an ecological constraints model of eusocial evolution, early genetic studies reported high levels of relatedness in naked mole-rats, providing a compelling argument that low dispersal rates and consanguineous mating (inbreeding as a mating system) are the driving forces for the evolution of this eusocial species. One caveat to accepting this long-held view is that the original genetic studies were based on limited sampling from the species' geographic distribution. A growing body of evidence supports a contrary view, with the original samples not representative of the species-rather reflecting a single founder event, establishing a small population south of the Athi River. Our study is the first to address these competing hypotheses by examining patterns of molecular variation in colonies sampled from north and south of the Athi and Tana rivers, which based on our results, serve to isolate genetically distinct populations of naked mole-rats. Although colonies south of the Athi River share a single mtDNA haplotype and are fixed at most microsatellite loci, populations north of the Athi River are considerably more variable. Our findings support the position that the low variation observed in naked mole-rat populations south of the Athi River reflects a founder event, rather than a consequence of this species' unusual mating system. © 2015 John Wiley & Sons Ltd.

Study of Biometric Identification Method Based on Naked Footprint

Directory of Open Access Journals (Sweden)

Raji Rafiu King

2013-10-01

Full Text Available The scale of deployment of biometric identity-verification systems has recently seen an enormous increase owing to the need for more secure and reliable way of identifying people. Footprint identification which can be defined as the measurement of footprint features for recognizing the identity of a user has surfaced recently. This study is based on a biometric personal identification method using static footprint features viz. friction ridge / texture and foot shape / silhouette. To begin with, naked footprints of users are captured; images then undergo pre processing followed by the extraction of two features; shape using Gradient Vector Flow （GVF） snake model and minutiae extraction respectively. Matching is then effected based on these two features followed by a fusion of these two results for either a reject or accept decision. Our shape matching feature is based on cosine similarity while the texture one is based on miniature score matching. The results from our research establish that the naked footprint is a credible biometric feature as two barefoot impressions of an individual match perfectly while that of two different persons shows a great deal of dissimilarity. Normal 0 false false false IN X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Doi: 10.12777/ijse.5.2.29-35 How to cite this article: King

Naked-eye sensor for rapid determination of mercury ion.

Science.gov (United States)

Liu, Jing; Wu, Dapeng; Yan, Xiaohui; Guan, Yafeng

2013-11-15

A naked-eye paper sensor for rapid determination of trace mercury ion in water samples was designed and demonstrated. The mercury-sensing rhodamine B thiolactone was immobilized in silica matrices and the silica matrices were impregnated firmly and uniformly in the filter paper. As water samples flow through the filter paper, the membrane color will change from white to purple red, which could be observed obviously with naked eye, when concentration of mercury ions equals to or exceeds 10nM, the maximum residue level in drinking water recommended by U.S. EPA. The color change can also be recorded by a flatbed scanner and then digitized, reducing the detection limit of Hg(2+) down to 1.2 nM. Moreover, this method is extremely specific for Hg(2+) and shows a high tolerance ratio of interferent coexisting ions. The presence of Na(+) (2 mM), K(+) (2 mM), Fe(3+) (0.1 mM), Zn(2+) (0.1 mM), Mg(2+) (0.1 mM), Ni(2+) (50 μM), Co(2+) (50 μM), Cd(2+) (50 μM), Pb(2+) (50 μM), Cu(2+) (50 μM) and Ag(+) (3.5 μM) did not interfere with the detection of Hg(2+) (25 nM). Finally, the present method was applied in the detection of Hg(2+) in mineral water, tap water and pond water. Copyright © 2013 Elsevier B.V. All rights reserved.

Altered composition of liver proteasome assemblies contributes to enhanced proteasome activity in the exceptionally long-lived naked mole-rat.

Directory of Open Access Journals (Sweden)

Karl A Rodriguez

Full Text Available The longest-lived rodent, the naked mole-rat (Bathyergidae; Heterocephalus glaber, maintains robust health for at least 75% of its 32 year lifespan, suggesting that the decline in genomic integrity or protein homeostasis routinely observed during aging, is either attenuated or delayed in this extraordinarily long-lived species. The ubiquitin proteasome system (UPS plays an integral role in protein homeostasis by degrading oxidatively-damaged and misfolded proteins. In this study, we examined proteasome activity in naked mole-rats and mice in whole liver lysates as well as three subcellular fractions to probe the mechanisms behind the apparently enhanced effectiveness of UPS. We found that when compared with mouse samples, naked mole-rats had significantly higher chymotrypsin-like (ChT-L activity and a two-fold increase in trypsin-like (T-L in both whole lysates as well as cytosolic fractions. Native gel electrophoresis of the whole tissue lysates showed that the 20S proteasome was more active in the longer-lived species and that 26S proteasome was both more active and more populous. Western blot analyses revealed that both 19S subunits and immunoproteasome catalytic subunits are present in greater amounts in the naked mole-rat suggesting that the observed higher specific activity may be due to the greater proportion of immunoproteasomes in livers of healthy young adults. It thus appears that proteasomes in this species are primed for the efficient removal of stress-damaged proteins. Further characterization of the naked mole-rat proteasome and its regulation could lead to important insights on how the cells in these animals handle increased stress and protein damage to maintain a longer health in their tissues and ultimately a longer life.

Cutaneous and periodontal inputs to the cerebellum of the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Sarko, Diana K; Leitch, Duncan B; Catania, Kenneth C

2013-01-01

The naked mole-rat (Heterocephalus glaber) is a small fossorial rodent with specialized dentition that is reflected by the large cortical area dedicated to representation of the prominent incisors. Due to naked mole-rats' behavioral reliance on the incisors for digging and for manipulating objects, as well as their ability to move the lower incisors independently, we hypothesized that expanded somatosensory representations of the incisors would be present within the cerebellum in order to accommodate a greater degree of proprioceptive, cutaneous, and periodontal input. Multiunit electrophysiological recordings targeting the ansiform lobule were used to investigate tactile inputs from receptive fields on the entire body with a focus on the incisors. Similar to other rodents, a fractured somatotopy appeared to be present with discrete representations of the same receptive fields repeated within each folium of the cerebellum. These findings confirm the presence of somatosensory inputs to a large area of the naked mole-rat cerebellum with particularly extensive representations of the lower incisors and mystacial vibrissae. We speculate that these extensive inputs facilitate processing of tactile cues as part of a sensorimotor integration network that optimizes how sensory stimuli are acquired through active exploration and in turn adjusts motor outputs (such as independent movement of the lower incisors). These results highlight the diverse sensory specializations and corresponding brain organizational schemes that have evolved in different mammals to facilitate exploration of and interaction with their environment.

Cutaneous and periodontal inputs to the cerebellum of the naked mole-rat (Heterocephalus glaber

Directory of Open Access Journals (Sweden)

Diana K Sarko

2013-11-01

Full Text Available The naked mole-rat (Heterocephalus glaber is a small fossorial rodent with specialized dentition that is reflected by the large cortical area dedicated to representation of the prominent incisors. Due to naked mole-rats’ behavioral reliance on the incisors for digging and for manipulating objects, as well as their ability to move the lower incisors independently, we hypothesized that expanded somatosensory representations of the incisors would be present within the cerebellum in order to accommodate a greater degree of proprioceptive, cutaneous, and periodontal input. Multiunit electrophysiological recordings targeting the ansiform lobule were used to investigate tactile inputs from receptive fields on the entire body with a focus on the incisors. Similar to other rodents, a fractured somatotopy appeared to be present with discrete representations of the same receptive fields repeated within each folium of the cerebellum. These findings confirm the presence of somatosensory inputs to a large area of the naked mole-rat cerebellum with particularly extensive representations of the lower incisors and mystacial vibrissae. We speculate that these extensive inputs facilitate processing of tactile cues as part of a sensorimotor integration network that optimizes how sensory stimuli are acquired through active exploration and in turn adjusts motor outputs (such as independent movement of the lower incisors. These results highlight the diverse sensory specializations and corresponding brain organizational schemes that have evolved in different mammals to facilitate exploration of and interaction with their environment.

Productive performance of naked neck chickens that were fed leaf meal shrubs

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Santos M Herrera G.

2015-12-01

Full Text Available Objective. To compare the productive performance of naked neck chickens (phases of initiation, growth and final that were fed meals Gliricidia sepium, Cajanus cajan and Morus alba leaves. Materials and methods. 192 chickens, 1-84 days of age were distributed in a randomized block design with three experimental groups (5% of shrub in the diet, 48 animals/ group, eight replicates/ treatment, six animals/ reply and three animals/ sex in each replicate were used. The control group consumed diet based on corn and soybeans. They were reared on floor. Weighed every seven days. Weight gain, voluntary intake, conversion, balance and efficiency of feed utilization were calculated. Results. The highest total feed intake and average daily gain in rearing were 37.43g 9509.96 g respectively for M. alba (p<0.05, which also presented the best efficiency of energy and protein. Meanwhile, G. sepium showed the lowest values. Conclusions. It is possible to replace 5% of corn and soy in the diet of naked neck chickens, with the inclusion of leaf meal M. alba and get a favorable productive behavior.

Very low-energy and low-fluence ion beam bombardment of naked plasmid DNA

International Nuclear Information System (INIS)

Norarat, R.; Semsang, N.; Anuntalabhochai, S.; Yu, L.D.

2009-01-01

Ion beam bombardment of biological organisms has been recently applied to mutation breeding of both agricultural and horticultural plants. In order to explore relevant mechanisms, this study employed low-energy ion beams to bombard naked plasmid DNA. The study aimed at simulation of the final stage of the process of the ion beam bombardment of real cells to check whether and how very low-energy and low-fluence of ions can induce mutation. Argon and nitrogen ions at 5 keV and 2.5 keV respectively bombarded naked plasmid DNA pGFP to very low-fluences, an order of 10 13 ions/cm 2 . Subsequently, DNA states were analyzed using electrophoresis. Results provided evidences that the very low-energy and low-fluence ion bombardment indeed altered the DNA structure from supercoil to short linear fragments through multiple double strand breaks and thus induced mutation, which was confirmed by transfer of the bombarded DNA into bacteria Escherichia coli and subsequent expression of the marker gene.

David Cronenberg, author of naked lunch: Intersemiotic translation as transcreation

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Rosângela Fachel de Medeiros

2016-05-01

Full Text Available This paper presents and analyzes the intersemiotic translation process performed by filmmaker David Cronenberg of William Burroughs' novel Naked Lunch, and the intertextual bifurcations involved in this process. Investigating the similarities and differences between the creative worlds of both artists and how they reframe each other. For this, are used as the theoretical the idea of transcreation proposed by Haroldo de Campos, and the notion of the translator as a reader proposed by Jorge Luis Borges.

Two very long chain fatty acid acyl-CoA synthetase genes, acs-20 and acs-22, have roles in the cuticle surface barrier in Caenorhabditis elegans.

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Eriko Kage-Nakadai

Full Text Available In multicellular organisms, the surface barrier is essential for maintaining the internal environment. In mammals, the barrier is the stratum corneum. Fatty acid transport protein 4 (FATP4 is a key factor involved in forming the stratum corneum barrier. Mice lacking Fatp4 display early neonatal lethality with features such as tight, thick, and shiny skin, and a defective skin barrier. These symptoms are strikingly similar to those of a human skin disease called restrictive dermopathy. FATP4 is a member of the FATP family that possesses acyl-CoA synthetase activity for very long chain fatty acids. How Fatp4 contributes to skin barrier function, however, remains to be elucidated. In the present study, we characterized two Caenorhabditis elegans genes, acs-20 and acs-22, that are homologous to mammalian FATPs. Animals with mutant acs-20 exhibited defects in the cuticle barrier, which normally prevents the penetration of small molecules. acs-20 mutant animals also exhibited abnormalities in the cuticle structure, but not in epidermal cell fate or cell integrity. The acs-22 mutants rarely showed a barrier defect, whereas acs-20;acs-22 double mutants had severely disrupted barrier function. Moreover, the barrier defects of acs-20 and acs-20;acs-22 mutants were rescued by acs-20, acs-22, or human Fatp4 transgenes. We further demonstrated that the incorporation of exogenous very long chain fatty acids into sphingomyelin was reduced in acs-20 and acs-22 mutants. These findings indicate that C. elegans Fatp4 homologue(s have a crucial role in the surface barrier function and this model might be useful for studying the fundamental molecular mechanisms underlying human skin barrier and relevant diseases.

Performance and Heterosis of Indigenous Chicken Crossbreed (Naked Neck x Frizzled Feather In The Humid Tropics

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Jeremiah Monday Nwenya

2017-12-01

Full Text Available Forty-four (44 birds (about 50 weeks old male and female inbred naked necked and frizzle feathered chickens were crossed to generate F1 crossbred chicken that were used to evaluate the performance and heterosis effects. Data taken on 180 chicks (97 NN and 83 FF day-old chick weight (BWT0, body weight (BWT, daily average feed intake (AFI, feed conversion ratio (FCR, brooding and rearing mortalities, linear body measurements (LBM: body length, wing length, keel length, shank length and breast width were used to estimate heterosis and performance of F1 progenies. Results of the experiment showed positive heterosis with significant differences among the F1 progenies over their parents in body weight, average feed intake and feed conversion ratio. The reciprocal cross (i.e. frizzle feather rooster x naked neck hen showed a significant improvement in their performances genetically, explaining that better results are achieved through crossbreeding of these indigenous breeds. With reference to their body linear parameters, the reciprocal cross of naked neck and frizzle feathered chickens developed higher body length, whereas the main crosses performed better in their wing length, keel length, shank length and body width respectively, mainly after 8 weeks suggesting that earlier performance was attributable to maternal influences.

Characteristic properties of proteins from pre-ecdysial cuticle of larvae and pupae of the mealworm Tenebrio molitor

DEFF Research Database (Denmark)

Andersen, Svend Olav

2002-01-01

Proteins extracted from the cuticle of pharate larvae and pupae of the mealworm Tenebrio molitor are more soluble at low temperatures than at higher temperatures, a behaviour characteristic of hydrophobic proteins. When the temperature of an unfractionated cuticular extract is raised from 4 to 25...... undergo plasticization during and/or immediately after ecdysis....

Hornet cuticle - a composite structure comprised of a series of duplex lamellae attenuating toward the interior of the body

NARCIS (Netherlands)

Ishay, JS; Kirshboim, S; Steinberg, D; Kalicharan, D; Jongebloed, WL

Our study deals with the ultramicroscopic structure of the yellow pigmented cuticular stripes on the abdomen of the oriental hornet Vespa orientalis (Hymenoptera, Vespinae). The abdominal cuticle is composed of numerous (more than 25) lamellae which progressively attenuate as one proceeds from the

Effects of wind and simulated acid mist on leaf cuticles

International Nuclear Information System (INIS)

Hoad, S.P.; Jeffree, C.E.; Grace, J.

1994-01-01

The combined effect of wind and simulated acid mist on leaf cuticles was investigated in beech (Fagus sylvatica L.) and birch (Betula pubescens Ehr.). Macroscopic and microscopic features of wind damage are described. Visibly damaged leaf area and the numbers of microscopic cuticular lesions were measured. The cuticular conductance to water vapour (g c ) of the astomatous adaxial surfaces of the leaves was measured by a gravimetric method. Field experimenntal sites were selected to provide either: 1. Direct wind action on widely-spaced plants caused by high speed and impaction of wind-blown particles, but with minimal mutual leaf abrasion 2. Indirect wind action via a high degree of mutual abrasion between closely-spaced plants. Direct wind action increased water loss via the leaf adaxial cuticle two- to three-fold in each species, by increasing the numbers of microscopic cuticular lesions. Indirect wind action caused more visible damage to leaves than direct wind action, increased g c by about threefold compared with complete shelter, and induced the most cuticular lesions. Acid mists at pH 3 or pH 5 were applied to the plants in situ at weekly intervals over a 100-day period. In sheltered plants, no effect of acid mist was detected on visibly damaged leaf area, the numbers of microscopic cuticular lesions, or on g c . However, acid mists in combination with wind exposure caused significant effects on cuticular integrity that were dependent on the type of wind action. Direct wind action combined with pH 3 acid mist resulted in the largest numbers of microscopic cuticular lesions, and the highest g c . By contrast, indirect wind action combined with pH 3 acid mist caused most visible damage to leaf tissue, but fewer microscopic lesions, and lower g c , than in plants treated with water mist. In severely-abraded leaves exposed to indirect wind action and low-pH acid rain, g c may be reduced by wound-isolation of blocks of non-functional leaf tissue. (orig.)

Stationary spherical shells around Kerr-Newman naked singularities

International Nuclear Information System (INIS)

Zdenek Stuchlik; Stanislav Hledik

1998-01-01

It is shown that in the field of some Kerr-Newman naked singularities a stationary spherical shell of charged dust can exist, with the specific charge being the same for all particles of the dusty shell. Gravitational attractions acting on the particles are balanced by electromagnetic repulsion in such a way that the shell is stable against radial perturbations. Particles of the shell move along orbits with constant latitude and radius. Rotation of the shell is differential. The shell is corotating relative to static observers at infinity, but it is counter rotating relative to the family of locally non-rotating observers. No such a shell can exist in the field of Kerr-Newman black holes. (authors)

Particle Collision Near 1 + 1-Dimensional Horava-Lifshitz Black Hole and Naked Singularity

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M. Halilsoy

2017-01-01

Full Text Available The unbounded center-of-mass (CM energy of oppositely moving colliding particles near horizon emerges also in 1+1-dimensional Horava-Lifshitz gravity. This theory has imprints of renormalizable quantum gravity characteristics in accordance with the method of simple power counting. Surprisingly the result obtained is not valid for a 1-dimensional Compton-like process between an outgoing photon and an infalling massless/massive particle. It is possible to achieve unbounded CM energy due to collision between infalling photons and particles. The source of outgoing particles may be attributed to an explosive process just outside the horizon for a black hole and the naturally repulsive character for the case of a naked singularity. It is found that absence of angular momenta in 1+1-dimension does not yield unbounded energy for collisions in the vicinity of naked singularities.

Androgen receptor distribution in the social decision-making network of eusocial naked mole-rats.

Science.gov (United States)

Holmes, Melissa M; Van Mil, Spencer; Bulkowski, Camila; Goldman, Sharry L; Goldman, Bruce D; Forger, Nancy G

2013-11-01

Naked mole-rats are highly social rodents that live in large groups and exhibit a strict reproductive and social hierarchy. Only a few animals in each colony breed; the remainder are non-reproductive and are socially subordinate to breeders. We have examined androgen receptor immunoreactive (AR+) cells in brain regions comprising the recently described social decision-making network in subordinate and breeder naked mole-rats of both sexes. We find that subordinates have a significantly higher percentage of AR+ cells in all brain regions expressing this protein. By contrast, there were no significant effects of sex and no sex-by-status interactions on the percentage of AR+ cells. Taken together with previous findings, the present data complete a systematic assessment of the distribution of AR protein in the social decision-making network of the eusocial mammalian brain and demonstrate a significant role for social status in the regulation of this protein throughout many nodes of this network. Copyright © 2013 Elsevier B.V. All rights reserved.

Resilin and chitinous cuticle form a composite structure for energy storage in jumping by froghopper insects

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Shaw Stephen R

2008-09-01

Full Text Available Abstract Background Many insects jump by storing and releasing energy in elastic structures within their bodies. This allows them to release large amounts of energy in a very short time to jump at very high speeds. The fastest of the insect jumpers, the froghopper, uses a catapult-like elastic mechanism to achieve their jumping prowess in which energy, generated by the slow contraction of muscles, is released suddenly to power rapid and synchronous movements of the hind legs. How is this energy stored? Results The hind coxae of the froghopper are linked to the hinges of the ipsilateral hind wings by pleural arches, complex bow-shaped internal skeletal structures. They are built of chitinous cuticle and the rubber-like protein, resilin, which fluoresces bright blue when illuminated with ultra-violet light. The ventral and posterior end of this fluorescent region forms the thoracic part of the pivot with a hind coxa. No other structures in the thorax or hind legs show this blue fluorescence and it is not found in larvae which do not jump. Stimulating one trochanteral depressor muscle in a pattern that simulates its normal action, results in a distortion and forward movement of the posterior part of a pleural arch by 40 μm, but in natural jumping, the movement is at least 100 μm. Conclusion Calculations showed that the resilin itself could only store 1% to 2% of the energy required for jumping. The stiffer cuticular parts of the pleural arches could, however, easily meet all the energy storage needs. The composite structure therefore, combines the stiffness of the chitinous cuticle with the elasticity of resilin. Muscle contractions bend the chitinous cuticle with little deformation and therefore, store the energy needed for jumping, while the resilin rapidly returns its stored energy and thus restores the body to its original shape after a jump and allows repeated jumping.

The effects of oxotremorine, epibatidine, atropine, mecamylamine and naloxone in the tail-flick, hot-plate, and formalin tests in the naked mole-rat (Heterocephalus glaber)

DEFF Research Database (Denmark)

Dulu, Thomas D; Kanui, Titus I; Towett, Philemon K

2014-01-01

The naked mole-rat (Heterocephalus glaber) is a promising animal model for the study of pain mechanisms, therefore a thorough characterization of this species is essential. The aim of the present study was to establish the naked mole-rat as a model for studying the cholinergic receptor system in ...

Solid-State (13)C NMR Delineates the Architectural Design of Biopolymers in Native and Genetically Altered Tomato Fruit Cuticles.

Science.gov (United States)

Chatterjee, Subhasish; Matas, Antonio J; Isaacson, Tal; Kehlet, Cindie; Rose, Jocelyn K C; Stark, Ruth E

2016-01-11

Plant cuticles on outer fruit and leaf surfaces are natural macromolecular composites of waxes and polyesters that ensure mechanical integrity and mitigate environmental challenges. They also provide renewable raw materials for cosmetics, packaging, and coatings. To delineate the structural framework and flexibility underlying the versatile functions of cutin biopolymers associated with polysaccharide-rich cell-wall matrices, solid-state NMR spectra and spin relaxation times were measured in a tomato fruit model system, including different developmental stages and surface phenotypes. The hydrophilic-hydrophobic balance of the cutin ensures compatibility with the underlying polysaccharide cell walls; the hydroxy fatty acid structures of outer epidermal cutin also support deposition of hydrophobic waxes and aromatic moieties while promoting the formation of cell-wall cross-links that rigidify and strengthen the cuticle composite during fruit development. Fruit cutin-deficient tomato mutants with compromised microbial resistance exhibit less efficient local and collective biopolymer motions, stiffening their cuticular surfaces and increasing their susceptibility to fracture.

Quantitative analysis and classification of AFM images of human hair.

Science.gov (United States)

Gurden, S P; Monteiro, V F; Longo, E; Ferreira, M M C

2004-07-01

The surface topography of human hair, as defined by the outer layer of cellular sheets, termed cuticles, largely determines the cosmetic properties of the hair. The condition of the cuticles is of great cosmetic importance, but also has the potential to aid diagnosis in the medical and forensic sciences. Atomic force microscopy (AFM) has been demonstrated to offer unique advantages for analysis of the hair surface, mainly due to the high image resolution and the ease of sample preparation. This article presents an algorithm for the automatic analysis of AFM images of human hair. The cuticular structure is characterized using a series of descriptors, such as step height, tilt angle and cuticle density, allowing quantitative analysis and comparison of different images. The usefulness of this approach is demonstrated by a classification study. Thirty-eight AFM images were measured, consisting of hair samples from (a) untreated and bleached hair samples, and (b) the root and distal ends of the hair fibre. The multivariate classification technique partial least squares discriminant analysis is used to test the ability of the algorithm to characterize the images according to the properties of the hair samples. Most of the images (86%) were found to be classified correctly.

A preliminary phylogeny of the Palearctic naked-toed geckos (Reptilia: Squamata: Gekkonidae) with taxonomic implications.

Science.gov (United States)

Bauer, Aaron M; Masroor, Rafaqat; Titus-McQuillan, James; Heinicke, Matthew P; Daza, Juan D; Jackman, Todd R

2013-01-08

Palearctic naked-toed geckos are a group of gekkonid geckos that range from North Africa to northern India and western China, with their greatest diversity in Iran and Pakistan. Relationships among the constituent genera remain incompletely resolved and the monophyly of key genera remains unverified. Further, competing classifications are in current use and many species have been allocated to different genera by different authors. We used both mitochondrial (ND2) and nuclear genes (RAG1, PDC) to explore relationships among representatives of all but one genus in the group (Rhinogecko), including four genera not previously included in phylogenetic analyses (Asiocolotes, Altigekko, Indogekko, and Siwaligekko). Siwaligekko (and presumably other Tibeto-Himalayan species often referred to Cyrtopodion) are more closely related to tropical Asian Cyrtodactylus than to Palearctic naked-toed geckos. Sampled species of Asiocolotes and Altigekko are sister taxa, but both genera are here considered junior subjective synonyms of Altiphylax. Cyrtopodion sensu lato is non-monophyletic; Mediodactylus and Tenuidactylus, which have variably been considered as subgenera or synonyms of Cyrtopodion are both valid genera. Indogekko is embedded within Cyrtopodion and is here treated as a subgenus. Bunopus and Crossobamon are closely related to one-another, and with Agamura are interdigitated among taxa previously assigned to Cyrtopodion. Our data confirm the previous identification of a Saharo-Arabian Stenodactylus/Tropiocolotes/Pseudoceramodactylus clade and verify that Microgecko and Alsophylax are not members of the main clade of Palearctic naked-toed geckos. Osteological differences between Tropiocolotes and Microgecko, formerly treated as congeneric, are discussed and illustrated. The divergence between Cyrtodactylus and the Palearctic naked-toed clade predates the initial collision of the Indian and Eurasian plates, but deeper divergences within both groups are

The identification of a gene (Cwp1), silenced during Solanum evolution, which causes cuticle microfissuring and dehydration when expressed in tomato fruit.

Science.gov (United States)

Hovav, Ran; Chehanovsky, Noam; Moy, Michal; Jetter, Reinhard; Schaffer, Arthur A

2007-11-01

One of the most intriguing phenomena of fleshy fruit is the ability to maintain high water content at maturity, even following harvest. This is accomplished by a fruit cuticle that is highly impermeable to water diffusion. In this paper, we report on a novel genotype of tomato, developed via introgression from the wild species Solanum habrochaites, which is characterized by microfissuring of the fruit cuticle and dehydration of the mature fruit. The microfissure/dehydration phenotype is inherited as a single gene, termed Cwp1 (cuticular water permeability). The gene was fine mapped, and its identity was determined by map-based cloning and differential expression analysis in near-isogenic lines. Causality of the Cwp1 gene was shown by the heterologous transgenic expression of the gene in the cultivated tomato, which caused a microfissured fruit cuticle leading to dehydrated fruit. Cwp1 encodes for a protein of unidentified function in the DUF833 domain family. The gene is expressed in the fruit epidermis of the dehydrating genotype harbouring the wild-species introgression, but not in the cultivated tomato. It is expressed only in the primitive green-fruited wild tomato species, but is not expressed in the cultivated Solanum lycopersicum and the closely related Solanum cheesmaniae and Solanum pimpinellifolium, indicating a pre-adaptive role for Cwp1 silencing in the evolution and domestication of the cultivated tomato.

Naked mole-rat cortical neurons are resistant to acid-induced cell death

OpenAIRE

Husson, Zoé; Smith, Ewan S

2018-01-01

Abstract Regulation of brain pH is a critical homeostatic process and changes in brain pH modulate various ion channels and receptors and thus neuronal excitability. Tissue acidosis, resulting from hypoxia or hypercapnia, can activate various proteins and ion channels, among which acid-sensing ion channels (ASICs) a family of primarily Na+ permeable ion channels, which alongside classical excitotoxicity causes neuronal death. Naked mole-rats (NMRs, Heterocephalus glaber) are ...

Naked Mole Rat Induced Pluripotent Stem Cells and Their Contribution to Interspecific Chimera

Directory of Open Access Journals (Sweden)

Sang-Goo Lee

2017-11-01

Full Text Available Naked mole rats (NMRs are exceptionally long-lived, cancer-resistant rodents. Identifying the defining characteristics of these traits may shed light on aging and cancer mechanisms. Here, we report the generation of induced pluripotent stem cells (iPSCs from NMR fibroblasts and their contribution to mouse-NMR chimeric embryos. Efficient reprogramming could be observed under N2B27+2i conditions. The iPSCs displayed a characteristic morphology, expressed pluripotent markers, formed embryoid bodies, and showed typical differentiation patterns. Interestingly, NMR embryonic fibroblasts and the derived iPSCs had propensity for a tetraploid karyotype and were resistant to forming teratomas, but within mouse blastocysts they contributed to both interspecific placenta and fetus. Gene expression patterns of NMR iPSCs were more similar to those of human than mouse iPSCs. Overall, we uncovered unique features of NMR iPSCs and report a mouse-NMR chimeric model. The iPSCs and associated cell culture systems can be used for a variety of biological and biomedical applications.

Extended Postnatal Brain Development in the Longest-Lived Rodent: Prolonged Maintenance of Neotenous Traits in the Naked Mole-Rat Brain.

Science.gov (United States)

Orr, Miranda E; Garbarino, Valentina R; Salinas, Angelica; Buffenstein, Rochelle

2016-01-01

The naked mole-rat (NMR) is the longest-lived rodent with a maximum lifespan >31 years. Intriguingly, fully-grown naked mole-rats (NMRs) exhibit many traits typical of neonatal rodents. However, little is known about NMR growth and maturation, and we question whether sustained neotenous features when compared to mice, reflect an extended developmental period, commensurate with their exceptionally long life. We tracked development from birth to 3 years of age in the slowest maturing organ, the brain, by measuring mass, neural stem cell proliferation, axonal, and dendritic maturation, synaptogenesis and myelination. NMR brain maturation was compared to data from similar sized rodents, mice, and to that of long-lived mammals, humans, and non-human primates. We found that at birth, NMR brains are significantly more developed than mice, and rather are more similar to those of newborn primates, with clearly laminated hippocampi and myelinated white matter tracts. Despite this more mature brain at birth than mice, postnatal NMR brain maturation occurs at a far slower rate than mice, taking four-times longer than required for mice to fully complete brain development. At 4 months of age, NMR brains reach 90% of adult size with stable neuronal cytostructural protein expression whereas myelin protein expression does not plateau until 9 months of age in NMRs, and synaptic protein expression continues to change throughout the first 3 years of life. Intriguingly, NMR axonal composition is more similar to humans than mice whereby NMRs maintain expression of three-repeat (3R) tau even after brain growth is complete; mice experience an abrupt downregulation of 3R tau by postnatal day 8 which continues to diminish through 6 weeks of age. We have identified key ages in NMR cerebral development and suggest that the long-lived NMR may provide neurobiologists an exceptional model to study brain developmental processes that are compressed in common short-lived laboratory animal models.

Extended postnatal brain development in the longest-lived rodent: prolonged maintenance of neotenous traits in the naked mole-rat brain

Directory of Open Access Journals (Sweden)

Miranda E. Orr

2016-11-01

Full Text Available The naked mole-rat (NMR is the longest-lived rodent with a maximum lifespan >31 years. Intriguingly, fully-grown naked mole-rats (NMRs exhibit many traits typical of neonatal rodents. However, little is known about NMR growth and maturation, and we question whether sustained neotenous features when compared to mice, reflect an extended developmental period, commensurate with their exceptionally long life. We tracked development from birth to three years of age in the slowest maturing organ, the brain, by measuring mass, neural stem cell proliferation, axonal and dendritic maturation, synaptogenesis and myelination. NMR brain maturation was compared to data from similar sized rodents, mice, and to that of long-lived mammals, humans and non-human primates. We found that at birth, NMR brains are significantly more developed than mice, and rather are more similar to those of newborn primates, with clearly laminated hippocampi and myelinated white matter tracts. Despite this more mature brain at birth than mice, postnatal NMR brain maturation occurs at a far slower rate than mice, taking four-times longer than required for mice to fully complete brain development. At four months of age, NMR brains reach 90% of adult size with stable neuronal cytostructural protein expression whereas myelin protein expression does not plateau until nine months of age in NMRs, and synaptic protein expression continues to change throughout the first three years of life. Intriguingly, NMR axonal composition is more similar to humans than mice whereby NMRs maintain expression of three-repeat (3R tau even after brain growth is complete; mice experience an abrupt downregulation of 3R tau by postnatal day 8 which continues to diminish through six weeks of age. We have identified key ages in NMR cerebral development and suggest that the long-lived NMR may provide neurobiologists an exceptional model to study brain developmental processes that are compressed in common short

Rapid micromotor-based naked-eye immunoassay.

Science.gov (United States)

de Ávila, Berta Esteban-Fernández; Zhao, Mingjiao; Campuzano, Susana; Ricci, Francesco; Pingarrón, José M; Mascini, Marcello; Wang, Joseph

2017-05-15

A dynamic micromotor-based immunoassay, exemplified by cortisol detection, based on the use of tubular micromotors functionalized with a specific antibody is described. The use of antibody-functionalized micromotors offers huge acceleration of both direct and competitive cortisol immunoassays, along with greatly enhanced sensitivity of direct and competitive immunoassays. The dramatically improved speed and sensitivity reflect the greatly increased likelihood of antibody-cortisol contacts and fluid mixing associated with the dynamic movement of these microtube motors and corresponding bubble generation that lead to a highly efficient and rapid recognition process. Rapid naked-eye detection of cortisol in the sample is achieved in connection to use of horseradish peroxidase (HRP) tag and TMB/H 2 O 2 system. Key parameters of the competitive immunoassay (e.g., incubation time and reaction volume) were optimized. This fast visual micromotor-based sensing approach enables "on the move" specific detection of the target cortisol down to 0.1μgmL -1 in just 2min, using ultrasmall (50µL) sample volumes. Copyright © 2017 Elsevier B.V. All rights reserved.

Silencing honey bee naked cuticle (nkd) reduces Nosema ceranae replication and disease levels

Science.gov (United States)

Nosema ceranae is a new and emerging microsporidian parasite of European honey bees, Apis mellifera that has been implicated in alarming colony losses worldwide. RNA interference (RNAi), a post-transcriptional gene silencing mechanism, has emerged as a potent and specific strategy for controlling in...

A permeable cuticle is associated with the release of reactive oxygen species and induction of innate immunity.

Directory of Open Access Journals (Sweden)

Floriane L'Haridon

2011-07-01

Full Text Available Wounded leaves of Arabidopsis thaliana show transient immunity to Botrytis cinerea, the causal agent of grey mould. Using a fluorescent probe, histological staining and a luminol assay, we now show that reactive oxygen species (ROS, including H(2O(2 and O(2 (-, are produced within minutes after wounding. ROS are formed in the absence of the enzymes Atrboh D and F and can be prevented by diphenylene iodonium (DPI or catalase. H(2O(2 was shown to protect plants upon exogenous application. ROS accumulation and resistance to B. cinerea were abolished when wounded leaves were incubated under dry conditions, an effect that was found to depend on abscisic acid (ABA. Accordingly, ABA biosynthesis mutants (aba2 and aba3 were still fully resistant under dry conditions even without wounding. Under dry conditions, wounded plants contained higher ABA levels and displayed enhanced expression of ABA-dependent and ABA-reporter genes. Mutants impaired in cutin synthesis such as bdg and lacs2.3 are already known to display a high level of resistance to B. cinerea and were found to produce ROS even when leaves were not wounded. An increased permeability of the cuticle and enhanced ROS production were detected in aba2 and aba3 mutants as described for bdg and lacs2.3. Moreover, leaf surfaces treated with cutinase produced ROS and became more protected to B. cinerea. Thus, increased permeability of the cuticle is strongly linked with ROS formation and resistance to B. cinerea. The amount of oxalic acid, an inhibitor of ROS secreted by B. cinerea could be reduced using plants over expressing a fungal oxalate decarboxylase of Trametes versicolor. Infection of such plants resulted in a faster ROS accumulation and resistance to B. cinerea than that observed in untransformed controls, demonstrating the importance of fungal suppression of ROS formation by oxalic acid. Thus, changes in the diffusive properties of the cuticle are linked with the induction ROS and attending

Endocrine function and neurobiology of the longest-living rodent, the naked mole-rat.

Science.gov (United States)

Edrey, Yael H; Park, Thomas J; Kang, Hyesin; Biney, Adriana; Buffenstein, Rochelle

2011-01-01

Animals that have evolved exceptional capabilities, such as extraordinary longevity may reveal pertinent and potentially critical insights into biomedical research that are not readily apparent in standard laboratory animals. Naked mole-rats (Heterocephalus glaber; NMRs) are extremely long-lived (30 years) mouse-sized rodents. They clearly have evolved superior anti-aging mechanisms as evident by the markedly attenuated age-related decline in physiological function, sustained reproductive capacity and pronounced cancer resistance throughout their long-lives. These eusocial rodents, like the social insects, live in colonies with breeding restricted to one female and a few males. Subordinates are sexually monomorphic, yet retain the ability to become breeders, and can undergo growth surges and neural modifications at any time throughout their life. This plasticity in physiological and behavioral aspects may have contributed to their long-lives. Naked mole-rats show numerous adaptations to life underground including extreme tolerance of hypoxia, acid insensitivity, as well as independence of photoendocrine systems. Here we review what is known about their unique social structure, sensory systems, endocrinology and neurobiology, and highlight areas that may be pertinent to biogerontology. Copyright © 2010 Elsevier Inc. All rights reserved.

Naked gene therapy of hepatocyte growth factor for dextran sulfate sodium-induced colitis in mice

International Nuclear Information System (INIS)

Kanbe, Takamasa; Murai, Rie; Mukoyama, Tomoyuki; Murawaki, Yoshiyuki; Hashiguchi, Ko-ichi; Yoshida, Yoko; Tsuchiya, Hiroyuki; Kurimasa, Akihiro; Harada, Ken-ichi; Yashima, Kazuo; Nishimuki, Eiji; Shabana, Noriko; Kishimoto, Yukihiro; Kojyo, Haruhiko; Miura, Kunihiko; Murawaki, Yoshikazu; Kawasaki, Hironaka; Shiota, Goshi

2006-01-01

Ulcerative colitis (UC) is progressive and relapsing disease. To explore the therapeutic effects of naked gene therapy of hepatocyte growth factor (HGF) on UC, the SRα promoter driving HGF gene was intrarectally administered to the mice in which colitis was induced by dextran sulfate sodium (DSS). Expression of the transgene was seen in surface epithelium, lamina propria, and muscularis mucosae. The HGF-treated mice showed reduced colonic mucosal damage and increased body weights, compared with control mice (P < 0.01 and P < 0.05, respectively). The HGF-treated mice displayed increased number of PCNA-positive cells and decreased number of apoptotic cells than in control mice (P < 0.01, each). Phosphorylated AKT was dramatically increased after HGF gene administration, however, phosphorylated ERK1/2 was not altered. Microarray analysis revealed that HGF induced expression of proliferation- and apoptosis-associated genes. These data suggest that naked HGF gene delivery causes therapeutic effects through regulation of many downstream genes

The starry room naked eye astronomy in the intimate universe

CERN Document Server

Schaaf, Fred

2002-01-01

This inspiring and enriching book, a collection of essays that evokes the beauty and wonder of the night sky, explains to beginning skywatchers how to find and where to look for specific celestial objects. Author Fred Schaaf, once described as a naturalist in the tradition of Henry David Thoreau and John Burroughs, reveals an intense love of his subject and a keen knowledge of the optimum ways of viewing astronomical phenomena with the naked eye. Schaaf not only describes such special sights as an eyelash-thin moon, a shooting star, streaking comets, and a lunar eclipse, but he also explains w

A Novel, Extremely Elongated, and Endocellular Bacterial Symbiont Supports Cuticle Formation of a Grain Pest Beetle.

Science.gov (United States)

Hirota, Bin; Okude, Genta; Anbutsu, Hisashi; Futahashi, Ryo; Moriyama, Minoru; Meng, Xian-Ying; Nikoh, Naruo; Koga, Ryuichi; Fukatsu, Takema

2017-09-26

The saw-toothed grain beetle, Oryzaephilus surinamensis (Silvanidae), is a cosmopolitan stored-product pest. Early studies on O. surinamensis in the 1930s described the presence of peculiar bacteriomes harboring endosymbiotic bacteria in the abdomen. Since then, however, the microbiological nature of the symbiont has been elusive. Here we investigated the endosymbiotic system of O. surinamensis in detail. In the abdomen of adults, pupae, and larvae, four oval bacteriomes were consistently identified, whose cytoplasm was full of extremely elongated tubular bacterial cells several micrometers wide and several hundred micrometers long. Molecular phylogenetic analysis identified the symbiont as a member of the Bacteroidetes , in which the symbiont was the most closely related to the endosymbiont of a grain pest beetle, Rhyzopertha dominica (Bostrichidae). The symbiont was detected in developing embryos, corroborating vertical symbiont transmission through host generations. The symbiont gene showed AT-biased nucleotide composition and accelerated molecular evolution, plausibly reflecting degenerative evolution of the symbiont genome. When the symbiont infection was experimentally removed, the aposymbiotic insects grew and reproduced normally, but exhibited a slightly but significantly more reddish cuticle and lighter body mass. These results indicate that the symbiont of O. surinamensis is not essential for the host's growth and reproduction but contributes to the host's cuticle formation. Symbiont genome sequencing and detailed comparison of fitness parameters between symbiotic and aposymbiotic insects under various environmental conditions will provide further insights into the symbiont's biological roles for the stored-product pest. IMPORTANCE Some beetles notorious as stored-product pests possess well-developed symbiotic organs called bacteriomes for harboring specific symbiotic bacteria, although their biological roles have been poorly understood. Here we report

An empirical examination of the relationship between naked shorting and share prices around the announcement of a firm’s need for external capital

Directory of Open Access Journals (Sweden)

Austin Murphy

2012-12-01

Full Text Available This research finds some empirical evidence that the sale of stock without delivering shares can contribute to pressuring down the equity prices of companies seeking to raise capital. By allowing for the delayed effects on prices of limit orders by naked shorts, a significant negative impact on equity value per share is discovered but only for naked short selling by market makers and only on stocks of firms in urgent need of external financing.

Naked Gold Nanoparticles and hot Electrons in Water.

Science.gov (United States)

Ghandi, Khashayar; Wang, Furong; Landry, Cody; Mostafavi, Mehran

2018-05-08

The ionizing radiation in aqueous solutions of gold nanoparticles, stabilized by electrostatic non-covalent intermolecular forces and steric interactions, with antimicrobial compounds, are investigated with picosecond pulse radiolysis techniques. Upon pulse radiolysis of an aqueous solution containing very low concentrations of gold nanoparticles with naked surfaces available in water (not obstructed by chemical bonds), a change to Cerenkov spectrum over a large range of wavelengths are observed and pre-solvated electrons are captured by gold nanoparticles exclusively (not by ionic liquid surfactants used to stabilize the nanoparticles). The solvated electrons are also found to decay rapidly compared with the decay kinetics in water. These very fast reactions with electrons in water could provide an enhanced oxidizing zone around gold nanoparticles and this could be the reason for radio sensitizing behavior of gold nanoparticles in radiation therapy.

Primary structure of a 14 kDa basic structural protein (Lm-76) from the cuticle of the migratory locust, Locusta migratoria

DEFF Research Database (Denmark)

Andersen, Jens S.; Andersen, S O; Højrup, P

1993-01-01

The complete amino acid sequence of a 14 kDa structural protein (LM-76) isolated from pharate cuticle of the locust, Locusta migratoria, was determined by Edman degradation of the intact protein and enzymatically derived peptides. Plasma desorption and electrospray mass spectrometry was used as a...

Monitoring agrochemical diffusion through cuticle wax with coherent Raman scattering

Science.gov (United States)

Gaunt, Nicholas P.; Thomson, Niall; Padia, Faheem; Moger, Julian

2018-02-01

The world's population is increasing rapidly and higher calorific diets are becoming more common; as a consequence the demand for grain is predicted to increase by more than 50% by 2050 without a significant increase in the available agricultural land. Maximising the productivity of the existing agricultural land is key to maintaining food security and agrochemicals continue to be a key enabler for the efficiency gains required. However, agrochemicals can be susceptible to significant losses and thus often require further chemical to be applied to compensate. Sources of such losses include spray drift, poor spray retention/capture by the target and poor penetration through the plant cuticle. Adjuvants can be used to help mitigate such losses but characterising how they alter the movement of the active ingredients (AIs) can be challenging. In this contribution we demonstrate the use of coherent Raman Scattering (CRS) as a tool to enable in-situ, real-time, label free characterisation of agrochemical AI as they move through wax.

Is it really naked? On cosmic censorship in string theory

International Nuclear Information System (INIS)

Frolov, Andrei V.

2004-01-01

We investigate the possibility of cosmic censorship violation in string theory using a characteristic double-null code, which penetrates horizons and is capable of resolving the spacetime all the way to the singularity. We perform high-resolution numerical simulations of the evolution of negative mass initial scalar field profiles, which were argued to provide a counterexample to cosmic censorship conjecture for AdS-asymptotic spacetimes in five-dimensional supergravity. In no instances formation of naked singularity is seen. Instead, numerical evidence indicates that black holes form in the collapse. Our results are consistent with earlier numerical studies, and explicitly show where the 'no black hole' argument breaks

Status of GENIUS-TF-II and TF-III-The long-term stability of naked detectors in liquid nitrogen

Energy Technology Data Exchange (ETDEWEB)

Klapdor-Kleingrothaus, H.V. [Max-Planck-Institut fuer Kernphysik, P.O. Box 10 39 80, D-69029 Heidelberg (Germany)]. E-mail: H.Klapdor@mpi-hd.mpg.de; Krivosheina, I.V. [Max-Planck-Institut fuer Kernphysik, P.O. Box 10 39 80, D-69029 Heidelberg (Germany)

2006-10-15

GENIUS-TF-II is a setup of six naked high purity Ge detectors (15kg) in liquid nitrogen in Gran Sasso. It has been installed in October, 2004-after the first four naked Ge detectors had been installed on May 5, 2003 (GENIUS-TF-I). The GENIUS-Test-Facility (GENIUS-TF) is the first and up to now only setup ever testing the novel technique aiming at extreme background reduction in search for rare decays in particular underground. The goal of GENIUS-TF was to test some key operational parameters of the full GENIUS project proposal in 1997 [H.V. Klapdor-Kleingrothaus, Int. J. Mod. Phys. A 13 (1998) 3953; H.V. Klapdor-Kleingrothaus, J. Hellmig, M. Hirsch, GENIUS-Proposal, 20 November 1997; J. Hellmig and H.V. Klapdor-Kleingrothaus, Z. Phys. A 359 ( 1997) 351 and nucl-ex/9801004; H.V. Klapdor-Kleingrothaus, M. Hirsch, Z. Phys. A 359 (1997) 361; H.V. Klapdor-Kleingrothaus, J. Hellmig, M. Hirsch, J. Phys. G 24 (1998) 483; H.V. Klapdor-Kleingrothaus, CERN Courier, November 1997, pp. 16-18]. Simultaneous physical goal is to search for the annual modulation of the Dark Matter signal [H.V. Klapdor-Kleingrothaus, et al., Nucl. Instr. and Meth. A 481 (2002) 149; C. Tomei, A. Dietz, I. Krivosheina, H.V. Klapdor-Kleingrothaus, Nucl. Instr. and Meth. 508 (2003) 343]. After operation of GENIUS-TF over three years with finally six naked Ge detectors (15kg) in liquid nitrogen in Gran Sasso we realize serious problems for realization of a full-size GENIUS-like experiment: (1) Background from Rn222 diffusing into the setup, on a level far beyond the expectation. (2) Limited long-term stability of naked detectors in liquid nitrogen as result of increasing leakage current. None of the six detectors is running after three years with the nominal leakage current. Three of the six detectors do not work any more at all. The results of our three years of investigation of the long-term stability may cast doubt on the possibility to perform full GENIUS-like projects.

Status of GENIUS-TF-II and TF-III-The long-term stability of naked detectors in liquid nitrogen

International Nuclear Information System (INIS)

Klapdor-Kleingrothaus, H.V.; Krivosheina, I.V.

2006-01-01

GENIUS-TF-II is a setup of six naked high purity Ge detectors (15kg) in liquid nitrogen in Gran Sasso. It has been installed in October, 2004-after the first four naked Ge detectors had been installed on May 5, 2003 (GENIUS-TF-I). The GENIUS-Test-Facility (GENIUS-TF) is the first and up to now only setup ever testing the novel technique aiming at extreme background reduction in search for rare decays in particular underground. The goal of GENIUS-TF was to test some key operational parameters of the full GENIUS project proposal in 1997 [H.V. Klapdor-Kleingrothaus, Int. J. Mod. Phys. A 13 (1998) 3953; H.V. Klapdor-Kleingrothaus, J. Hellmig, M. Hirsch, GENIUS-Proposal, 20 November 1997; J. Hellmig and H.V. Klapdor-Kleingrothaus, Z. Phys. A 359 ( 1997) 351 and nucl-ex/9801004; H.V. Klapdor-Kleingrothaus, M. Hirsch, Z. Phys. A 359 (1997) 361; H.V. Klapdor-Kleingrothaus, J. Hellmig, M. Hirsch, J. Phys. G 24 (1998) 483; H.V. Klapdor-Kleingrothaus, CERN Courier, November 1997, pp. 16-18]. Simultaneous physical goal is to search for the annual modulation of the Dark Matter signal [H.V. Klapdor-Kleingrothaus, et al., Nucl. Instr. and Meth. A 481 (2002) 149; C. Tomei, A. Dietz, I. Krivosheina, H.V. Klapdor-Kleingrothaus, Nucl. Instr. and Meth. 508 (2003) 343]. After operation of GENIUS-TF over three years with finally six naked Ge detectors (15kg) in liquid nitrogen in Gran Sasso we realize serious problems for realization of a full-size GENIUS-like experiment: (1) Background from Rn222 diffusing into the setup, on a level far beyond the expectation. (2) Limited long-term stability of naked detectors in liquid nitrogen as result of increasing leakage current. None of the six detectors is running after three years with the nominal leakage current. Three of the six detectors do not work any more at all. The results of our three years of investigation of the long-term stability may cast doubt on the possibility to perform full GENIUS-like projects

Arabidopsis ECERIFERUM9 involvement in cuticle formation and maintenance of plant water status

KAUST Repository

Lu, Shiyou

2012-05-25

Mutation of the ECERIFERUM9 (CER9) gene in Arabidopsis (Arabidopsis thaliana) causes elevated amounts of 18-carbon-length cutin monomers and a dramatic shift in the cuticular wax profile (especially on leaves) toward the very-long-chain free fatty acids tetracosanoic acid (C24) and hexacosanoic acid (C26). Relative to the wild type, cer9 mutants exhibit elevated cuticle membrane thickness over epidermal cells and cuticular ledges with increased occlusion of the stomatal pore. The cuticular phenotypes of cer9 are associated with delayed onset of wilting in plants experiencing water deficit, lower transpiration rates, and improved water use efficiency measured as carbon isotope discrimination. The CER9 protein thus encodes a novel determinant of plant drought tolerance-associated traits, one whose deficiency elevates cutin synthesis, redistributes wax composition, and suppresses transpiration. Map-based cloning identified CER9, and sequence analysis predicted that it encodes an E3 ubiquitin ligase homologous to yeast Doa10 (previously shown to target endoplasmic reticulum proteins for proteasomal degradation). To further elucidate CER9 function, the impact of CER9 deficiency on interactions with other genes was examined using double mutant and transcriptome analyses. For both wax and cutin, cer9 showed mostly additive effects with cer6, long-chain acyl-CoA synthetase1 (lacs1), and lacs2 and revealed its role in early steps of both wax and cutin synthetic pathways. Transcriptome analysis revealed that the cer9 mutation affected diverse cellular processes, with primary impact on genes associated with diverse stress responses. The discovery of CER9 lays new groundwork for developing novel cuticle-based strategies for improving the drought tolerance and water use efficiency of crop plants. © 2012 American Society of Plant Biologists. All Rights Reserved.

Cuticle-degrading proteases and toxins as virulence markers of Beauveria bassiana (Balsamo) Vuillemin.

Science.gov (United States)

Cito, Annarita; Barzanti, Gian Paolo; Strangi, Agostino; Francardi, Valeria; Zanfini, Assunta; Dreassi, Elena

2016-09-01

Beauveria bassiana is one of the most known entomopathogenic fungal species and its entomopathogenic mechanism involves several bioactive metabolites, mainly cuticle-degrading enzymes and toxic molecules, which are predicted to play a key role as virulence factors. In this study six Beauveria bassiana strains (B 13/I03, B 13/I11, B 13/I49, B 13/I57, B 13/I63, and B 13/I64) were assayed against Tenebrio molitor larvae. Enzymatic activity of total proteases and specifically Pr 1 and Pr 2, as well as the production of toxic compounds were investigated in each fungal strain. Toxins were detected both in vitro-in medium filtrates and mycelia-and in vivo-in Tenebrio molitor larvae infected by the fungal strains tested. B 13/I11 and B 13/I63 strains showed the most significant entomopathogenic activity against Tenebrio molitor larvae (cumulative mortality rate 100 and 97%, respectively; average survival time 5.85 and 6.74 days, respectively). A widely variable and fungal strain-dependent enzymatic activity of total proteases, Pr 1 and Pr 2 was found. Beauvericin, beauvericin A and bassianolide resulted the most prevalent toxins detected in the substrates analyzed. It has been found that an increase of beauvericin content in vivo resulted significantly correlated to a decrease of Tenebrio molitor larvae average survival time in entomopathogenic bioassay (inverse correlation). The involvement of beauvericin in B. bassiana entomopathogenic process is confirmed; in vitro analysis of cuticle degrading proteases activity and toxins production in relation to the methods adopted resulted insufficient for a rapid screening to determine the virulence of B. bassiana strains against Tenebrio molitor larvae. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

FARINOGRAPHIC EVALUATION OF WHEAT DOUGH ENRICHED WITH INULIN, NAKED BARLEY, MALT AND POTEX ADDITION

Directory of Open Access Journals (Sweden)

Marián Tokár

2015-02-01

Full Text Available One of the most important biological substances consumed in insufficient quantity is fibre that is often deficient in the diet. In general, dietary fibre is edible part of plants, or similar carbohydrates, that are resistant to digestion and absorption in the small intestine. Nowadays, there are many sources of fibre available for bakery industry, whether through addition of non-traditional bread cereals or through isolated form as additives. Except to supposed increase the nutritional value of bakery products with added fiber and raw materials containing fiber is necessary to think about their technological quality and rheological properties of dough. The aim of this experimental work was to investigate the effect of the addition of selected polysaccharides (inulin, Potex - potato fiber and non-bakery crops (naked barley, malt containing significant polysaccharides used in the mixture with wheat flour type T-650 in different ratios on the basis of farinographic evaluations. Based on the results of rheological measurements we found out that quality of dough was deteriorating proportionally to the amount of used additives. On the other hand, positively could be considered the increase of water absorption with addition of Potex and naked barley.

Retinal ganglion cell survival and axon regeneration after optic nerve injury in naked mole-rats.

Science.gov (United States)

Park, Kevin K; Luo, Xueting; Mooney, Skyler J; Yungher, Benjamin J; Belin, Stephane; Wang, Chen; Holmes, Melissa M; He, Zhigang

2017-02-01

In the adult mammalian central nervous system (CNS), axonal damage often triggers neuronal cell death and glial activation, with very limited spontaneous axon regeneration. In this study, we performed optic nerve injury in adult naked mole-rats, the longest living rodent, with a maximum life span exceeding 30 years, and found that injury responses in this species are quite distinct from those in other mammalian species. In contrast to what is seen in other mammals, the majority of injured retinal ganglion cells (RGCs) survive with relatively high spontaneous axon regeneration. Furthermore, injured RGCs display activated signal transducer and activator of transcription-3 (STAT3), whereas astrocytes in the optic nerve robustly occupy and fill the lesion area days after injury. These neuron-intrinsic and -extrinsic injury responses are reminiscent of those in "cold-blooded" animals, such as fish and amphibians, suggesting that the naked mole-rat is a powerful model for exploring the mechanisms of neuronal injury responses and axon regeneration in mammals. J. Comp. Neurol. 525:380-388, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Dominance and queen succession in captive colonies of the eusocial naked mole-rat, Heterocephalus glaber.

Science.gov (United States)

Clarke, F M; Faulkes, C G

1997-07-22

Naked mole-rat colonies exhibit a high reproductive skew, breeding being typically restricted to one female (the 'queen') and one to three males. Other colony members are reproductively suppressed, although this suppression can be reversed following the removal or death of the queen. We examined dominance and queen succession within captive colonies to investigate the relationship between urinary testosterone and cortisol, dominance rank and reproductive status; and to determine if behavioural and/or physiological parameters can be used as predictors of queen succession. Social structure was characterized by a linear dominance hierarchy before and after queen removal. Prior to queen removal, dominance rank was negatively correlated with body weight and urinary testosterone and cortisol titres in males and females. Queen removal results in social instability and aggression between high ranking individuals. Dominance rank appears to be a good predictor of reproductive status: queens are the highest ranking colony females and are succeeded by the next highest ranking females. The intense dominance-related aggression that accompanies reproductive succession in naked mole-rats provides empirical support for optimal skew theory.

Metabolic clues to salubrious longevity in the brain of the longest-lived rodent: the naked mole-rat.

Science.gov (United States)

Triplett, Judy C; Swomley, Aaron; Kirk, Jessime; Lewis, Katilyn; Orr, Miranda; Rodriguez, Karl; Cai, Jian; Klein, Jon B; Buffenstein, Rochelle; Butterfield, D Allan

2015-08-01

Naked mole-rats (NMRs) are the oldest-living rodent species. Living underground in a thermally stable ecological niche, NMRs have evolved certain exceptional traits, resulting in sustained health spans, negligible cognitive decline, and a pronounced resistance to age-related disease. Uncovering insights into mechanisms underlying these extraordinary traits involved in successful aging may conceivably provide crucial clues to extend the human life span and health span. One of the most fundamental processes inside the cell is the production of ATP, which is an essential fuel in driving all other energy-requiring cellular activities. Not surprisingly, a prominent hallmark in age-related diseases, such as neurodegeneration and cancer, is the impairment and dysregulation of metabolic pathways. Using a two-dimensional polyacrylamide gel electrophoresis proteomics approach, alterations in expression and phosphorylation levels of metabolic proteins in the brains of NMRs, aged 2-24 years, were evaluated in an age-dependent manner. We identified 13 proteins with altered levels and/or phosphorylation states that play key roles in various metabolic pathways including glycolysis, β-oxidation, the malate-aspartate shuttle, the Tricarboxylic Acid Cycle (TCA) cycle, the electron transport chain, NADPH production, as well as the production of glutamate. New insights into potential pathways involved in metabolic aspects of successful aging have been obtained by the identification of key proteins through which the NMR brain responds and adapts to the aging process and how the NMR brain adapted to resist age-related degeneration. This study examines the changes in the proteome and phosphoproteome in the brain of the naked mole-rat aged 2-24 years. We identified 13 proteins (labeled in red) with altered expression and/or phosphorylation levels that are conceivably associated with sustained metabolic functions in the oldest NMRs that may promote a sustained health span and life span. �

Regional differences in the surface temperature of Naked Neck laying hens in a semi-arid environment.

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de Souza, João Batista Freire; de Arruda, Alex Martins Varela; Domingos, Hérica Girlane Tertulino; de Macedo Costa, Leonardo Lelis

2013-05-01

The aim of this study was to evaluate the regional differences in the surface temperature of Naked Neck hens that were subjected to different temperatures in a semi-arid environment. The surface temperature was measured in four body regions (face, neck, legs and feathered area) of 60 Naked Neck hens. The following environmental variables were measured at the center of the shed: the black globe temperature (T G ), air temperature (T A ), wind speed (U) and relative humidity (R H ). The T A was divided into three classes: 1 (24.0-26.0 °C), 2 (26.1-28.9 °C) and 3 (29.0-31.0 °C). An analysis of variance was performed by the least squares method and a comparison of the means by the Tukey-Kramer test. The results showed a significant effect of T A class, the body region and the interaction between these two effects on the surface temperature. There was no significant difference between the T A classes for the face and neck. The legs and feathered area showed significant differences between the T A classes. Regarding the effect of body regions within each T A class, there was a significant difference among all regions in the three T A classes. In all T A classes the neck had the highest average followed by the face and legs. The feathered area showed the lowest average of the different T A classes. In conclusion, this study showed that there are regional differences in the surface temperature of Naked Neck hens, with the legs acting as thermal windows.

Social status and sex independently influence androgen receptor expression in the eusocial naked mole-rat brain.

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Holmes, Melissa M; Goldman, Bruce D; Forger, Nancy G

2008-08-01

Naked mole-rats (Heterocephalus glaber) are eusocial rodents that live in large subterranean colonies including a single breeding female and 1-3 breeding males; all other members of the colony, known as subordinates, are reproductively suppressed. We recently found that naked mole-rats lack many of the sex differences in the brain and spinal cord commonly found in other rodents. Instead, neural morphology is influenced by breeding status, such that breeders, regardless of sex, have more neurons than subordinates in the ventromedial nucleus of the hypothalamus (VMH), and larger overall volumes of the bed nucleus of the stria terminalis (BST), paraventricular nucleus (PVN) and medial amygdala (MeA). To begin to understand how breeding status influences brain morphology, we examined the distribution of androgen receptor (AR) immunoreactivity in gonadally intact breeders and subordinates of both sexes. All animals had AR+ nuclei in many of the same regions positive for AR in other mammals, including the VMH, BST, PVN, MeA, and the ventral portion of the premammillary nucleus (PMv). We also observed diffuse labeling throughout the preoptic area, demonstrating that distribution of the AR protein in presumptive reproductive brain nuclei is well-conserved, even in a species that exhibits remarkably little sexual dimorphism. In contrast to other rodents, however, naked mole-rats lacked AR+ nuclei in the suprachiasmatic nucleus and hippocampus. Males had more AR+ nuclei in the MeA, VMH, and PMv than did females. Surprisingly, breeders had significantly fewer AR+ nuclei than subordinates in all brain regions examined (VMH, BST, PVN, MeA, and PMv). Thus, social status is strongly correlated with AR immunoreactivity in this eusocial species.

Inter- and intra-specific cuticle variation between amphimictic and parthenogenetic species of root-knot nematode (Meloidogyne spp.) as revealed by a bacterial parasite (Pasteuria penetrans).

Science.gov (United States)

Davies, K G; Rowe, J A; Williamson, V M

2008-06-01

Specific host-parasite interactions exist between species and strains of plant parasitic root-knot nematodes and the Gram-positive bacterial hyperparasite Pasteuria penetrans. This bacterium produces endospores that adhere to the cuticle of migrating juveniles, germinate and colonise the developing female within roots. Endospore attachment of P. penetrans populations to second-stage juveniles of the root-knot nematode species Meloidogyne incognita and Meloidogyne hapla showed there were interactive differences between bacterial populations and nematode species. Infected females of M. incognita produced a few progeny which were used to establish two nematode lines from single infective juveniles encumbered with either three or 26 endospores. Single juvenile descent lines of each nematode species were produced to test whether cuticle variation was greater within M. hapla lines that reproduce by facultative meiotic parthenogenesis than within lines of M. incognita, which reproduces by obligate parthenogenesis. Assays revealed variability between broods of individual females derived from single second-stage juvenile descent lines of both M. incognita and M. hapla suggesting that progeny derived from a single individual can differ in spore adhesion in both sexual and asexual nematode species. These results suggest that special mechanisms that produced these functional differences in the cuticle surface may have evolved in both sexually and asexually reproducing nematodes as a strategy to circumvent infection by this specialised hyperparasite.

Physical properties of naked DNA influence nucleosome positioning and correlate with transcription start and termination sites in yeast

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Soler-López Montserrat

2011-10-01

Full Text Available Abstract Background In eukaryotic organisms, DNA is packaged into chromatin structure, where most of DNA is wrapped into nucleosomes. DNA compaction and nucleosome positioning have clear functional implications, since they modulate the accessibility of genomic regions to regulatory proteins. Despite the intensive research effort focused in this area, the rules defining nucleosome positioning and the location of DNA regulatory regions still remain elusive. Results Naked (histone-free and nucleosomal DNA from yeast were digested by microccocal nuclease (MNase and sequenced genome-wide. MNase cutting preferences were determined for both naked and nucleosomal DNAs. Integration of their sequencing profiles with DNA conformational descriptors derived from atomistic molecular dynamic simulations enabled us to extract the physical properties of DNA on a genomic scale and to correlate them with chromatin structure and gene regulation. The local structure of DNA around regulatory regions was found to be unusually flexible and to display a unique pattern of nucleosome positioning. Ab initio physical descriptors derived from molecular dynamics were used to develop a computational method that accurately predicts nucleosome enriched and depleted regions. Conclusions Our experimental and computational analyses jointly demonstrate a clear correlation between sequence-dependent physical properties of naked DNA and regulatory signals in the chromatin structure. These results demonstrate that nucleosome positioning around TSS (Transcription Start Site and TTS (Transcription Termination Site (at least in yeast is strongly dependent on DNA physical properties, which can define a basal regulatory mechanism of gene expression.

Trial watch: Naked and vectored DNA-based anticancer vaccines.

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Bloy, Norma; Buqué, Aitziber; Aranda, Fernando; Castoldi, Francesca; Eggermont, Alexander; Cremer, Isabelle; Sautès-Fridman, Catherine; Fucikova, Jitka; Galon, Jérôme; Spisek, Radek; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

2015-05-01

One type of anticancer vaccine relies on the administration of DNA constructs encoding one or multiple tumor-associated antigens (TAAs). The ultimate objective of these preparations, which can be naked or vectored by non-pathogenic viruses, bacteria or yeast cells, is to drive the synthesis of TAAs in the context of an immunostimulatory milieu, resulting in the (re-)elicitation of a tumor-targeting immune response. In spite of encouraging preclinical results, the clinical efficacy of DNA-based vaccines employed as standalone immunotherapeutic interventions in cancer patients appears to be limited. Thus, efforts are currently being devoted to the development of combinatorial regimens that allow DNA-based anticancer vaccines to elicit clinically relevant immune responses. Here, we discuss recent advances in the preclinical and clinical development of this therapeutic paradigm.

Cuticle expansion during feeding in the tick Amblyomma hebraeum (Acari: Ixodidae): The role of hydrostatic pressure.

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Kaufman, W Reuben; Kaufman, S; Flynn, Peter C

2016-05-01

Female Amblyomma hebraeum ticks (Acari: Ixodidae) increase their weight ∼10-fold during a 'slow phase of engorgement' (7-9 days), and a further 10-fold during the 'rapid phase' (12-24h). During the rapid phase, the cuticle thins by half, with a plastic (permanent) deformation of greater than 40% in two orthogonal directions. A stress of 2.5 MPa or higher is required to achieve this degree of deformation (Flynn and Kaufman, 2015). Using a dimensional analysis of the tick body and applying the Laplace equation, we calculated that the tick must achieve high internal hydrostatic pressures in order to engorge fully: greater than 55 kPa at a fed:unfed mass ratio of ∼20:1, when cuticle thinning commences (Flynn and Kaufman, 2011). In this study we used a telemetric pressure transducer system to measure the internal hydrostatic pressure of ticks during feeding. Sustained periods of irregular high frequency (>20 Hz) pulsatile bursts of high pressure (>55 kPa) were observed in two ticks: they had been cannulated just prior to the rapid phase of engorgement, and given access to a host rabbit for completion of the feeding cycle. The pattern of periods of high pressure generation varied over the feeding cycle and between the two specimens. We believe that these pressures exceed those reported so far for any other animal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Low sulfide levels and a high degree of cystathionine β-synthase (CBS activation by S-adenosylmethionine (SAM in the long-lived naked mole-rat

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Maja Dziegelewska

2016-08-01

Full Text Available Hydrogen sulfide (H2S is a gaseous signalling molecule involved in many physiological and pathological processes. There is increasing evidence that H2S is implicated in aging and lifespan control in the diet-induced longevity models. However, blood sulfide concentration of naturally long-lived species is not known. Here we measured blood sulfide in the long-lived naked mole-rat and five other mammalian species considerably differing in lifespan and found a negative correlation between blood sulfide and maximum longevity residual. In addition, we show that the naked mole-rat cystathionine β-synthase (CBS, an enzyme whose activity in the liver significantly contributes to systemic sulfide levels, has lower activity in the liver and is activated to a higher degree by S-adenosylmethionine compared to other species. These results add complexity to the understanding of the role of H2S in aging and call for detailed research on naked mole-rat transsulfuration.

Transcriptome Comparative Profiling of Barley eibi1 Mutant Reveals Pleiotropic Effects of HvABCG31 Gene on Cuticle Biogenesis and Stress Responsive Pathways

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Eviatar Nevo

2013-10-01

Full Text Available Wild barley eibi1 mutant with HvABCG31 gene mutation has low capacity to retain leaf water, a phenotype associated with reduced cutin deposition and a thin cuticle. To better understand how such a mutant plant survives, we performed a genome-wide gene expression analysis. The leaf transcriptomes between the near-isogenic lines eibi1 and the wild type were compared using the 22-k Barley1 Affymetrix microarray. We found that the pleiotropic effect of the single gene HvABCG31 mutation was linked to the co-regulation of metabolic processes and stress-related system. The cuticle development involved cytochrome P450 family members and fatty acid metabolism pathways were significantly up-regulated by the HvABCG31 mutation, which might be anticipated to reduce the levels of cutin monomers or wax and display conspicuous cuticle defects. The candidate genes for responses to stress were induced by eibi1 mutant through activating the jasmonate pathway. The down-regulation of co-expressed enzyme genes responsible for DNA methylation and histone deacetylation also suggested that HvABCG31 mutation may affect the epigenetic regulation for barley development. Comparison of transcriptomic profiling of barley under biotic and abiotic stresses revealed that the functions of HvABCG31 gene to high-water loss rate might be different from other osmotic stresses of gene mutations in barley. The transcriptional profiling of the HvABCG31 mutation provided candidate genes for further investigation of the physiological and developmental changes caused by the mutant.

Amyloid beta and the longest-lived rodent: the naked mole-rat as a model for natural protection from Alzheimer's disease.

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Edrey, Yael H; Medina, David X; Gaczynska, Maria; Osmulski, Pawel A; Oddo, Salvatore; Caccamo, Antonella; Buffenstein, Rochelle

2013-10-01

Amyloid beta (Aβ) is implicated in Alzheimer's disease (AD) as an integral component of both neural toxicity and plaque formation. Brains of the longest-lived rodents, naked mole-rats (NMRs) approximately 32 years of age, had levels of Aβ similar to those of the 3xTg-AD mouse model of AD. Interestingly, there was no evidence of extracellular plaques, nor was there an age-related increase in Aβ levels in the individuals examined (2-20+ years). The NMR Aβ peptide showed greater homology to the human sequence than to the mouse sequence, differing by only 1 amino acid from the former. This subtle difference led to interspecies differences in aggregation propensity but not neurotoxicity; NMR Aβ was less prone to aggregation than human Aβ. Nevertheless, both NMR and human Aβ were equally toxic to mouse hippocampal neurons, suggesting that Aβ neurotoxicity and aggregation properties were not coupled. Understanding how NMRs acquire and tolerate high levels of Aβ with no plaque formation could provide useful insights into AD, and may elucidate protective mechanisms that delay AD progression. Copyright © 2013 Elsevier Inc. All rights reserved.

Diversity of the bacterial and fungal microflora from the midgut and cuticle of phlebotomine sand flies collected in North-Western Iran.

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Mohammad Akhoundi

Full Text Available BACKGROUND: Phlebotomine sand flies are the vectors of the leishmaniases, parasitic diseases caused by Leishmania spp. Little is known about the prevalence and diversity of sand fly microflora colonizing the midgut or the cuticle. Particularly, there is little information on the fungal diversity. This information is important for development of vector control strategies. METHODOLOGY/PRINCIPAL FINDINGS: FIVE SAND FLY SPECIES: Phlebotomus papatasi, P. sergenti, P. kandelakii, P. perfiliewi and P. halepensis were caught in Bileh Savar and Kaleybar in North-Western Iran that are located in endemic foci of visceral leishmaniasis. A total of 35 specimens were processed. Bacterial and fungal strains were identified by routine microbiological methods. We characterized 39 fungal isolates from the cuticle and/or the midgut. They belong to six different genera including Penicillium (17 isolates, Aspergillus (14, Acremonium (5, Fusarium (1, Geotrichum (1 and Candida (1. We identified 33 Gram-negative bacteria: Serratia marcescens (9 isolates, Enterobacter cloacae (6, Pseudomonas fluorescens (6, Klebsiella ozaenae (4, Acinetobacter sp. (3, Escherichia coli (3, Asaia sp. (1 and Pantoea sp. (1 as well as Gram-positive bacteria Bacillus subtilis (5 and Micrococcus luteus (5 in 10 isolates. CONCLUSION/SIGNIFICANCE: Our study provides new data on the microbiotic diversity of field-collected sand flies and for the first time, evidence of the presence of Asaia sp. in sand flies. We have also found a link between physiological stages (unfed, fresh fed, semi gravid and gravid of sand flies and number of bacteria that they carry. Interestingly Pantoea sp. and Klebsiella ozaenae have been isolated in Old World sand fly species. The presence of latter species on sand fly cuticle and in the female midgut suggests a role for this arthropod in dissemination of these pathogenic bacteria in endemic areas. Further experiments are required to clearly delineate the vectorial

Model-based analysis of the torsional loss modulus in human hair and of the effects of cosmetic processing.

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Wortmann, Franz J; Wortmann, Gabriele; Haake, Hans-Martin; Eisfeld, Wolf

Torsional analysis of single human hairs is especially suited to determine the properties of the cuticle and its changes through cosmetic processing. The two primary parameters, which are obtained by free torsional oscillation using the torsional pendulum method, are storage ( G ') and loss modulus ( G ″). Based on previous work on G ', the current investigation focuses on G ″. The results show an increase of G ″ with a drop of G ' and vice versa , as is expected for a viscoelastic material well below its glass transition. The overall power of G ″ to discriminate between samples is quite low. This is attributed to the systematic decrease of the parameter values with increasing fiber diameter, with a pronounced correlation between G ″ and G '. Analyzing this effect on the basis of a core/shell model for the cortex/cuticle structure of hair by nonlinear regression leads to estimates for the loss moduli of cortex ( G ″ co ) and cuticle ( G ″ cu ). Although the values for G ″ co turn out to be physically not plausible, due to limitations of the applied model, those for G ″ cu are considered as generally realistic against relevant literature values. Significant differences between the loss moduli of the cuticle for the different samples provide insight into changes of the torsional energy loss due to the cosmetic processes and products, contributing toward a consistent view of torsional energy storage and loss, namely, in the cuticle of hair.

Seeing Beyond the Naked Eye in a Planetarium

Science.gov (United States)

Fairall, A.

2005-12-01

I have a philosophy that the traditional naked-eye sky, as usually shown in planetariums, should only be an introductory step in portraying the Universe. Consequently, over the years I have produced 'inter alia' various versions of an enhanced Milky Way (the latest based on Axel Mellenger's panorama), the extragalactic sky and the radio sky for projection on planetarium domes. I also put together a three-dimensional planetarium show-the audience being equipped with ChromDepth(tm) spectacles- which stepped from the Solar System to the cosmic microwave background. The advent of digital technology now makes all this much easier. Currently, Labyrinth, a visualization program developed in-house, serves much the same function as the Hayden Planetarium's Partiview, but also permits rendering and fl y-throughs of large-scale structures. It allows viewers to explore local cosmography. Labyrinth can produce images that operate with the 3-D spectacles; we have also produced a version of Partiview that does the same.

The evolution of eggshell cuticle in relation to nesting ecology

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Hauber, Mark E.

2016-01-01

Avian eggs are at risk of microbial infection prior to and during incubation. A large number of defence mechanisms have evolved in response to the severe costs imposed by these infections. The eggshell's cuticle is an important component of antimicrobial defence, and its role in preventing contamination by microorganisms in domestic chickens is well known. Nanometer-scale cuticular spheres that reduce microbial attachment and penetration have recently been identified on eggs of several wild avian species. However, whether these spheres have evolved specifically for antimicrobial defence is unknown. Here, we use comparative data on eggshell cuticular structure and nesting ecology to test the hypothesis that birds nesting in habitats with higher risk of infection (e.g. wetter and warmer) are more likely to evolve cuticular nanospheres on their eggshells than those nesting in less risky habitats. We found that nanostructuring, present in 54 of 296 analysed species, is the ancestral condition of avian eggshells and has been retained more often in taxa that nest in humid infection-prone environments, suggesting that they serve critical roles in antimicrobial egg defence. PMID:27488648

The Insulin-Like Growth Factor System in the Long-Lived Naked Mole-Rat.

Science.gov (United States)

Brohus, Malene; Gorbunova, Vera; Faulkes, Chris G; Overgaard, Michael T; Conover, Cheryl A

2015-01-01

Naked mole-rats (Heterocephalus glaber) (NMRs) are the longest living rodents known. They show negligible senescence, and are resistant to cancers and certain damaging effects associated with aging. The insulin-like growth factors (IGFs) have pluripotent actions, influencing growth processes in virtually every system of the body. They are established contributors to the aging process, confirmed by the demonstration that decreased IGF signaling results in life-extending effects in a variety of species. The IGFs are likewise involved in progression of cancers by mediating survival signals in malignant cells. This report presents a full characterization of the IGF system in the NMR: ligands, receptors, IGF binding proteins (IGFBPs), and IGFBP proteases. A particular emphasis was placed on the IGFBP protease, pregnancy-associated plasma protein-A (PAPP-A), shown to be an important lifespan modulator in mice. Comparisons of IGF-related genes in the NMR with human and murine sequences indicated no major differences in essential parts of the IGF system, including PAPP-A. The protease was shown to possess an intact active site despite the report of a contradictory genome sequence. Furthermore, PAPP-A was expressed and translated in NMRs cells and retained IGF-dependent proteolytic activity towards IGFBP-4 and IGF-independent activity towards IGFBP-5. However, experimental data suggest differential regulatory mechanisms for PAPP-A expression in NMRs than those described in humans and mice. This overall description of the IGF system in the NMR represents an initial step towards elucidating the complex molecular mechanisms underlying longevity, and how these animals have evolved to ensure a delayed and healthy aging process.

Kinetic study of solid phase demineralization by weak acids in one-step enzymatic bio-refinery of shrimp cuticles

OpenAIRE

Baron, Regis; Socol, Marius; Arhaliass, A.; Bruzac, Sandrine; Le Roux, Karine; Del Pino, J. Rodriguez; Berge, Jean-pascal; Kaas, Raymond

2015-01-01

We describe a one-step bio-refinery process for shrimp composites by-products. Its originality lies in a simple rapid (6 h) biotechnological cuticle fragmentation process that recovers all major compounds (chitins, peptides and minerals in particular calcium). The process consists of a controlled exogenous enzymatic proteolysis in a food-grade acidic medium allowing chitin purification (solid phase), and recovery of peptides and minerals (liquid phase). At a pH of between 3.5 and 4, protease ...

Naked singularity in the global structure of critical collapse spacetimes

International Nuclear Information System (INIS)

Frolov, Andrei V.; Pen, U.-L.

2003-01-01

We examine the global structure of scalar field critical collapse spacetimes using a characteristic double-null code. It can integrate past the horizon without any coordinate problems, due to the careful choice of constraint equations used in the evolution. The limiting sequence of sub- and supercritical spacetimes presents an apparent paradox in the expected Penrose diagrams, which we address in this paper. We argue that the limiting spacetime converges pointwise to a unique limit for all r>0, but not uniformly. The r=0 line is different in the two limits. We interpret that the two different Penrose diagrams differ by a discontinuous gauge transformation. We conclude that the limiting spacetime possesses a singular event, with a future removable naked singularity

A Novel, Extremely Elongated, and Endocellular Bacterial Symbiont Supports Cuticle Formation of a Grain Pest Beetle

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Bin Hirota

2017-09-01

Full Text Available The saw-toothed grain beetle, Oryzaephilus surinamensis (Silvanidae, is a cosmopolitan stored-product pest. Early studies on O. surinamensis in the 1930s described the presence of peculiar bacteriomes harboring endosymbiotic bacteria in the abdomen. Since then, however, the microbiological nature of the symbiont has been elusive. Here we investigated the endosymbiotic system of O. surinamensis in detail. In the abdomen of adults, pupae, and larvae, four oval bacteriomes were consistently identified, whose cytoplasm was full of extremely elongated tubular bacterial cells several micrometers wide and several hundred micrometers long. Molecular phylogenetic analysis identified the symbiont as a member of the Bacteroidetes, in which the symbiont was the most closely related to the endosymbiont of a grain pest beetle, Rhyzopertha dominica (Bostrichidae. The symbiont was detected in developing embryos, corroborating vertical symbiont transmission through host generations. The symbiont gene showed AT-biased nucleotide composition and accelerated molecular evolution, plausibly reflecting degenerative evolution of the symbiont genome. When the symbiont infection was experimentally removed, the aposymbiotic insects grew and reproduced normally, but exhibited a slightly but significantly more reddish cuticle and lighter body mass. These results indicate that the symbiont of O. surinamensis is not essential for the host’s growth and reproduction but contributes to the host’s cuticle formation. Symbiont genome sequencing and detailed comparison of fitness parameters between symbiotic and aposymbiotic insects under various environmental conditions will provide further insights into the symbiont’s biological roles for the stored-product pest.

Naked eye picometer resolution in a Michelson interferometer using conjugated twisted beams.

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Emile, Olivier; Emile, Janine

2017-01-15

Michelson interferometry is one of the most widely used techniques for accuracy measurements. Its main characteristic feature is to infer a displacement in one of the arms of the interferometer from a phase measurement. Two different twisted beams, also called vortex beams, with opposite twisted rotations in each arm of the interferometer interfere in a daisy flower-like pattern. The number of petals is twice the topological charge. Their position depends on the relative phase of the beams. Naked eye detection of 44 pm displacements is achieved. The sensitivity of such an interferometer together with possible further improvements, and applications are then discussed.

Low sulfide levels and a high degree of cystathionine β-synthase (CBS) activation by S-adenosylmethionine (SAM) in the long-lived naked mole-rat.

Science.gov (United States)

Dziegelewska, Maja; Holtze, Susanne; Vole, Christiane; Wachter, Ulrich; Menzel, Uwe; Morhart, Michaela; Groth, Marco; Szafranski, Karol; Sahm, Arne; Sponholz, Christoph; Dammann, Philip; Huse, Klaus; Hildebrandt, Thomas; Platzer, Matthias

2016-08-01

Hydrogen sulfide (H2S) is a gaseous signalling molecule involved in many physiological and pathological processes. There is increasing evidence that H2S is implicated in aging and lifespan control in the diet-induced longevity models. However, blood sulfide concentration of naturally long-lived species is not known. Here we measured blood sulfide in the long-lived naked mole-rat and five other mammalian species considerably differing in lifespan and found a negative correlation between blood sulfide and maximum longevity residual. In addition, we show that the naked mole-rat cystathionine β-synthase (CBS), an enzyme whose activity in the liver significantly contributes to systemic sulfide levels, has lower activity in the liver and is activated to a higher degree by S-adenosylmethionine compared to other species. These results add complexity to the understanding of the role of H2S in aging and call for detailed research on naked mole-rat transsulfuration. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Nanotribological and nanomechanical characterization of human hair using a nanoscratch technique

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Wei Guohua [Nanotribology Laboratory for Information Storage and MEMS/NEMS, Ohio State University, 650 Ackerman Road, Suite 255, Columbus, OH 43202 (United States); Bhushan, Bharat [Nanotribology Laboratory for Information Storage and MEMS/NEMS, Ohio State University, 650 Ackerman Road, Suite 255, Columbus, OH 43202 (United States)]. E-mail: bhushan.2@osu.edu

2006-06-15

Human hair ({approx}50-100 {mu}m in diameter) is a nanocomposite biological fiber with well-characterized microstructures, and is of great interest for both cosmetic science and materials science. Characterization of nanotribological and nanomechanical properties of human hair including the coefficient of friction and scratch resistance is essential to develop better shampoo and conditioner products and advance biological and cosmetic science. In this paper, the coefficient of friction and scratch resistance of Caucasian and Asian hair at virgin, chemo-mechanically damaged, and conditioner-treated conditions are measured using a nanoscratch technique with a Nano Indenter II system. The scratch tests were performed on both the single cuticle cell and multiple cuticle cells of each hair sample, and the scratch wear tracks were studied using scanning electron microscopy (SEM) after the scratch tests. The effect of soaking on the coefficient of friction, scratch resistance, hardness and Young's modulus of hair surface were also studied by performing experiments on hair samples which had been soaked in de-ionized water for 5 min. The nanotribological and nanomechanical properties of human hair as a function of hair structure (hair of different ethnicity), damage, treatment and soaking are discussed.

Nanotribological and nanomechanical characterization of human hair using a nanoscratch technique

International Nuclear Information System (INIS)

Wei Guohua; Bhushan, Bharat

2006-01-01

Human hair (∼50-100 μm in diameter) is a nanocomposite biological fiber with well-characterized microstructures, and is of great interest for both cosmetic science and materials science. Characterization of nanotribological and nanomechanical properties of human hair including the coefficient of friction and scratch resistance is essential to develop better shampoo and conditioner products and advance biological and cosmetic science. In this paper, the coefficient of friction and scratch resistance of Caucasian and Asian hair at virgin, chemo-mechanically damaged, and conditioner-treated conditions are measured using a nanoscratch technique with a Nano Indenter II system. The scratch tests were performed on both the single cuticle cell and multiple cuticle cells of each hair sample, and the scratch wear tracks were studied using scanning electron microscopy (SEM) after the scratch tests. The effect of soaking on the coefficient of friction, scratch resistance, hardness and Young's modulus of hair surface were also studied by performing experiments on hair samples which had been soaked in de-ionized water for 5 min. The nanotribological and nanomechanical properties of human hair as a function of hair structure (hair of different ethnicity), damage, treatment and soaking are discussed

First 10 kg of naked Germanium detectors in liquid nitrogen installed in the GENIUS-Test-Facility

International Nuclear Information System (INIS)

Klapdor-Kleingrothaus, H.V.; Chkvorets, O.; Krivosheina, I.V.; Strecker, H.; Tomei, C.

2003-01-01

The first four naked high-purity Germanium detectors were installed successfully in liquid nitrogen in the GENIUS-Test-Facility in the GRAN SASSO Underground Laboratory on May 5, 2003. This is the first time ever that this novel technique aiming at extreme background reduction in search for rare decays is going to be tested underground. First operational parameters are presented

Sequence analysis and heterologous expression of the wool cuticle-degrading enzyme encoding genes in Fusarium oxysporum 26-1.

Science.gov (United States)

Chaya, Etsushi; Suzuki, Tohru; Karita, Shuichi; Hanya, Akira; Yoshino-Yasuda, Shoko; Kitamoto, Noriyuki

2014-06-01

Two protease-like proteins, KrtA and KrtC, were identified in Fusarium oxysporum 26-1. Genes coding these proteins, krtA and krtC, were isolated and characterized. Recombinant KrtA (rKrtA) and KrtC (rKrtC) were successfully expressed in Aspergillus oryzae and secreted. The combination of rKrtA and rKrtC completely removed the cuticle of wool fibers. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

Science.gov (United States)

Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

2014-09-01

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

Energy Technology Data Exchange (ETDEWEB)

Thopan, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

2014-05-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms.

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

International Nuclear Information System (INIS)

Thopan, P.; Thongkumkoon, P.; Prakrajang, K.; Suwannakachorn, D.; Yu, L.D.

2014-01-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms

Differential effects of chronic fluoxetine on the behavior of dominant and subordinate naked mole-rats.

Science.gov (United States)

Mongillo, Daniel L; Kosyachkova, Ekaterina A; Nguyen, Tam M; Holmes, Melissa M

2014-01-01

Naked mole-rats are eusocial rodents that live in large subterranean colonies with a strict reproductive and social hierarchy. The breeding female (referred to as the queen) and 1 to 3 breeding males are the only reproductive members of the colony. Breeders are socially dominant and all other colony members are non-reproductive subordinates. The effects of manipulating the serotonergic neurotransmitter system on aggression and dominance behaviors are well studied in many species, but not in eusocial rodents like the naked mole-rat. The current study investigated how the serotonergic system influences aggressive/dominant behaviors in this species. To do this, two separate but related experiments were conducted: the effects of fluoxetine hydrochloride (FLX) on status-specific behaviors of subordinates (Experiment 1) and dominant queens (Experiment 2) were evaluated both in-colony and in a social-pairing paradigm. In accordance with our main hypothesis, chronic treatment of FLX attenuated the frequency and duration of aggression in queens, but not subordinates, when paired with an unfamiliar conspecific. Further exploration of pharmacological manipulation on status-specific behaviors of this eusocial species may elucidate the neurobiological mechanisms underlying their unique and rigid social hierarchy. Copyright © 2013 Elsevier B.V. All rights reserved.

Cessation of reproduction-related spine elongation after multiple breeding cycles in female naked mole-rats.

Science.gov (United States)

Dengler-Crish, Christine M; Catania, Kenneth C

2009-01-01

The breeding female or "queen" naked mole-rat has a uniquely elongated body morphology attributed to the lengthening of the lumbar vertebral column that occurs during pregnancy. It is unknown whether this vertebral growth is a continuous process, or associated only with early reproductive experience. We compared pregnancy-related bone elongation in nascent primiparous queens and established queens to determine if this vertebral expansion was a lifelong process in these females. We also investigated the impact of lactation on vertebral elongation in these mole-rats because it is known to be a time of significant bone loss in other mammals. Our data show that after eight or more pregnancies, established queens no longer experienced a net gain in lumbar spine length over the reproductive cycle, whereas the nascent breeders demonstrated significant spine lengthening over this time. Despite the lack of net spine lengthening in established breeders, our results indicated that these queens still experienced some pregnancy-specific vertebral elongation. In naked mole-rats, pregnancy-induced bone elongation may serve the dual purposes of first lengthening the spine, and then once optimal spine size is achieved, serving as a homeostatic mechanism that prepares the spine for the mineral demands of lactation. Anat Rec, 2009. (c) 2008 Wiley-Liss, Inc.

Naked (C5Me5)(2)M cations (M = Sc, Ti, and V) and their fluoroarene complexes

NARCIS (Netherlands)

Bouwkamp, MW; Budzelaar, PHM; Gercama, J; Morales, ID; de Wolf, J; Meetsma, A; Troyanov, SI; Teuben, JH; Hessen, B; Budzelaar, Peter H.M.; Hierro Morales, Isabel Del; Troyanov, Sergei I.

2005-01-01

The ionic metallocene complexes [Cp*M-2][BPh4] (CP* = C5Me5) of the trivalent 3d metals Sc, Ti, and V were synthesized and structurally characterized. For M Sc, the anion interacts weakly with the metal center through one of the phenyl groups, but for M = Ti and V, the cations are naked. They each

Interaction of Thermus thermophilus ArsC enzyme and gold nanoparticles naked-eye assays speciation between As(III) and As(V)

International Nuclear Information System (INIS)

Politi, Jane; De Stefano, Luca; Spadavecchia, Jolanda; Casale, Sandra; Fiorentino, Gabriella; Antonucci, Immacolata

2015-01-01

The thermophilic bacterium Thermus thermophilus HB27 encodes chromosomal arsenate reductase (TtArsC), the enzyme responsible for resistance to the harmful effects of arsenic. We report on adsorption of TtArsC onto gold nanoparticles for naked-eye monitoring of biomolecular interaction between the enzyme and arsenic species. Synthesis of hybrid biological–metallic nanoparticles has been characterized by transmission electron microscopy (TEM), ultraviolet-visible (UV–vis), dynamic light scattering (DLS) and phase modulated infrared reflection absorption (PM-IRRAS) spectroscopies. Molecular interactions have been monitored by UV–vis and Fourier transform-surface plasmon resonance (FT-SPR). Due to the nanoparticles’ aggregation on exposure to metal salts, pentavalent and trivalent arsenic solutions can be clearly distinguished by naked-eye assay, even at 85 μM concentration. Moreover, the assay shows partial selectivity against other heavy metals. (paper)

The Insulin-Like Growth Factor System in the Long-Lived Naked Mole-Rat.

Directory of Open Access Journals (Sweden)

Malene Brohus

Full Text Available Naked mole-rats (Heterocephalus glaber (NMRs are the longest living rodents known. They show negligible senescence, and are resistant to cancers and certain damaging effects associated with aging. The insulin-like growth factors (IGFs have pluripotent actions, influencing growth processes in virtually every system of the body. They are established contributors to the aging process, confirmed by the demonstration that decreased IGF signaling results in life-extending effects in a variety of species. The IGFs are likewise involved in progression of cancers by mediating survival signals in malignant cells. This report presents a full characterization of the IGF system in the NMR: ligands, receptors, IGF binding proteins (IGFBPs, and IGFBP proteases. A particular emphasis was placed on the IGFBP protease, pregnancy-associated plasma protein-A (PAPP-A, shown to be an important lifespan modulator in mice. Comparisons of IGF-related genes in the NMR with human and murine sequences indicated no major differences in essential parts of the IGF system, including PAPP-A. The protease was shown to possess an intact active site despite the report of a contradictory genome sequence. Furthermore, PAPP-A was expressed and translated in NMRs cells and retained IGF-dependent proteolytic activity towards IGFBP-4 and IGF-independent activity towards IGFBP-5. However, experimental data suggest differential regulatory mechanisms for PAPP-A expression in NMRs than those described in humans and mice. This overall description of the IGF system in the NMR represents an initial step towards elucidating the complex molecular mechanisms underlying longevity, and how these animals have evolved to ensure a delayed and healthy aging process.

An Endosperm-Associated Cuticle Is Required for Arabidopsis Seed Viability, Dormancy and Early Control of Germination.

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Julien De Giorgi

2015-12-01

Full Text Available Cuticular layers and seeds are prominent plant adaptations to terrestrial life that appeared early and late during plant evolution, respectively. The cuticle is a waterproof film covering plant aerial organs preventing excessive water loss and protecting against biotic and abiotic stresses. Cutin, consisting of crosslinked fatty acid monomers, is the most abundant and studied cuticular component. Seeds are dry, metabolically inert structures promoting plant dispersal by keeping the plant embryo in an arrested protected state. In Arabidopsis thaliana seeds, the embryo is surrounded by a single cell endosperm layer itself surrounded by a seed coat layer, the testa. Whole genome analyses lead us to identify cutin biosynthesis genes as regulatory targets of the phytohormones gibberellins (GA and abscisic acid (ABA signaling pathways that control seed germination. Cutin-containing layers are present in seed coats of numerous species, including Arabidopsis, where they regulate permeability to outer compounds. However, the role of cutin in mature seed physiology and germination remains poorly understood. Here we identify in mature seeds a thick cuticular film covering the entire outer surface of the endosperm. This seed cuticle is defective in cutin-deficient bodyguard1 seeds, which is associated with alterations in endospermic permeability. Furthermore, mutants affected in cutin biosynthesis display low seed dormancy and viability levels, which correlates with higher levels of seed lipid oxidative stress. Upon seed imbibition cutin biosynthesis genes are essential to prevent endosperm cellular expansion and testa rupture in response to low GA synthesis. Taken together, our findings suggest that in the course of land plant evolution cuticular structures were co-opted to achieve key physiological seed properties.

The plant cuticle is required for osmotic stress regulation of abscisic acid biosynthesis and osmotic stress tolerance in Arabidopsis

KAUST Repository

Wang, Zhenyu

2011-05-01

Osmotic stress activates the biosynthesis of abscisic acid (ABA). One major step in ABA biosynthesis is the carotenoid cleavage catalyzed by a 9-cis epoxycarotenoid dioxygenase (NCED). To understand the mechanism for osmotic stress activation of ABA biosynthesis, we screened for Arabidopsis thaliana mutants that failed to induce the NCED3 genee xpression in response to osmotic stress treatments. The ced1 (for 9-cis epoxycarotenoid dioxy genase defective 1) mutant isolated in this study showed markedly reduced expression of NCED3 in response to osmotic stress (polyethylene glycol)treatments compared with the wild type. Other ABA biosynthesis genes are also greatly reduced in ced1 under osmotic stress. ced1 mutant plants are very sensitive to even mild osmotic stress. Map-based cloning revealed unexpectedly thatCED1 encodes a putative a/b hydrolase domain-containing protein and is allelic to the BODYGUARD gene that was recently shown to be essential for cuticle biogenesis. Further studies discovered that other cut in biosynthesis mutants are also impaired in osmotic stress induction of ABA biosynthesis genes and are sensitive to osmotic stress. Our work demonstrates that the cuticle functions not merely as a physical barrier to minimize water loss but also mediates osmotic stress signaling and tolerance by regulating ABA biosynthesis and signaling. © 2011 American Society of Plant Biologists. All rights reserved.

Evidence of the exploitation of marine resource by the terrestrial insect Scapteriscus didactylus through stable isotope analyzes of its cuticle

Directory of Open Access Journals (Sweden)

Lelarge Caroline

2006-05-01

Full Text Available Abstract Background About 4 × 105 eggs in more than 5000 marine turtle nests are deposited every year on a 3.6 km long beach in French Guiana (South America. The dry biomass of eggs is estimated to be 5 × 103 kg, yet only 25% of this organic matter will return to the ocean in the form of hatchlings. Such amounts of organic matter are supposed to drive the functioning of the beach ecosystem. Previous studies have shown that egg predators and detritivorous organisms dominate the trophic relationships and the dynamics of the system. The role of a terrestrial insect Scapteriscus didactylus (Latreille, which damages up to 40% of the eggs of the marine turtle (Dermochelys coriacea, was unexpected. However it was impossible from direct observations to prove that the mole cricket consumed a significant amount of these eggs. Therefore, the precise place of the mole cricket in the nitrogen and carbon cycles of the beach ecosystem could not be determined. In order to answer this question, we looked for a marine signature of carbon and nitrogen source metabolized by the mole cricket. Results This study estimated the individual variability of δ13C and δ15N in the cuticle of Scapteriscus didactylus. The isotopic signature was compared between individuals collected at two sites: a village where mole crickets fed on human food scraps and the nearby Awala-Yalimapo beach, where food availability depends seasonally on the nesting sea turtles. The mole crickets collected near the habitations garbage showed no significant variations in the stable isotopic signature, within-and between age groups. On the contrary, isotopic values shifted from a signature of a terrestrial herbivorous diet in the mole crickets during early developmental stages, to isotopic values in adults in accordance with the exploitation of marine animal resources. Conclusion The heterogeneity of individual signatures during the year is due to a selective exploitation of the food sources

On the variably-charged black holes in general relativity: Hawking's radiation and naked singularities

International Nuclear Information System (INIS)

Ibohal, Ng

2002-01-01

In this paper variably-charged non-rotating Reissner-Nordstrom and rotating Kerr-Newman black holes are discussed. Such a variable charge e with respect to the polar coordinate r in the field equations is referred to as an electrical radiation of the black hole. It is shown that every electrical radiation e(r) of the non-rotating black hole leads to a reduction in its mass M by some quantity. If one considers such electrical radiation taking place continuously for a long time, then a continuous reduction of the mass may take place in the black-hole body and the original mass of the black hole may be evaporated completely. At that stage, the gravity of the object may depend only on the electromagnetic field, not on the mass. Immediately after the complete evaporation of the mass, if the next radiation continues, there may be creation of a new mass leading to the formation of a negative mass naked singularity. It appears that this new mass of the naked singularity would never decrease, but might increase gradually as the radiation continues forever. A similar investigation is also discussed in the case of a variably-charged rotating Kerr-Newman black hole. Thus, it has been shown by incorporating Hawking's evaporation of radiating black holes in the form of spacetime metrics, every electrical radiation of variably-charged rotating and non-rotating black holes may produce a change in the mass of the body without affecting the Maxwell scalar

A Major Facilitator Superfamily protein encoded by TcMucK gene is not required for cuticle pigmentation, growth and development in Tribolium castaneum.

Science.gov (United States)

Mun, Seulgi; Noh, Mi Young; Osanai-Futahashi, Mizuko; Muthukrishnan, Subbaratnam; Kramer, Karl J; Arakane, Yasuyuki

2014-06-01

Insect cuticle pigmentation and sclerotization (tanning) are vital physiological processes for insect growth, development and survival. We have previously identified several colorless precursor molecules as well as enzymes involved in their biosynthesis and processing to yield the mature intensely colored body cuticle pigments. A recent study indicated that the Bombyx mori (silkmoth) gene, BmMucK, which encodes a protein orthologous to a Culex pipiens quiquefasciatus (Southern house mosquito) cis,cis, muconate transporter, is a member of the "Major Facilitator Superfamily" (MFS) of transporter proteins and is associated with the appearance of pigmented body segments of naturally occurring body color mutants of B. mori. While RNA interference of the BmMucK gene failed to result in any observable phenotype, RNAi using a dsRNA for an orthologous gene from the red flour beetle, Tribolium castaneum, was reported to result in molting defects and darkening of the cuticle and some body parts, leading to the suggestion that orthologs of MucK genes may differ in their functions among insects. To verify the role and essentiality of the ortholog of this gene in development and body pigmentation function in T. castaneum we obtained cDNAs for the orthologous gene (TcMucK) from RNA isolated from the GA-1 wild-type strain of T. castaneum. The sequence of a 1524 nucleotides-long cDNA for TcMucK which encodes the putatively full-length protein, was assembled from two overlapping RT-PCR fragments and the expression profile of this gene during development was analyzed by real-time PCR. This cDNA encodes a 55.8 kDa protein consisting of 507 amino acid residues and includes 11 putative transmembrane segments. Transcripts of TcMucK were detected throughout all of the developmental stages analyzed. The function of this gene was explored by injection of two different double-stranded RNAs targeting different regions of the TcMucK gene (dsTcMucKs) into young larvae to down

Structural Changes and Lack of HCN1 Channels in the Binaural Auditory Brainstem of the Naked Mole-Rat (Heterocephalus glaber).

Science.gov (United States)

Gessele, Nikodemus; Garcia-Pino, Elisabet; Omerbašić, Damir; Park, Thomas J; Koch, Ursula

2016-01-01

Naked mole-rats (Heterocephalus glaber) live in large eu-social, underground colonies in narrow burrows and are exposed to a large repertoire of communication signals but negligible binaural sound localization cues, such as interaural time and intensity differences. We therefore asked whether monaural and binaural auditory brainstem nuclei in the naked mole-rat are differentially adjusted to this acoustic environment. Using antibody stainings against excitatory and inhibitory presynaptic structures, namely the vesicular glutamate transporter VGluT1 and the glycine transporter GlyT2 we identified all major auditory brainstem nuclei except the superior paraolivary nucleus in these animals. Naked mole-rats possess a well structured medial superior olive, with a similar synaptic arrangement to interaural-time-difference encoding animals. The neighboring lateral superior olive, which analyzes interaural intensity differences, is large and elongated, whereas the medial nucleus of the trapezoid body, which provides the contralateral inhibitory input to these binaural nuclei, is reduced in size. In contrast, the cochlear nucleus, the nuclei of the lateral lemniscus and the inferior colliculus are not considerably different when compared to other rodent species. Most interestingly, binaural auditory brainstem nuclei lack the membrane-bound hyperpolarization-activated channel HCN1, a voltage-gated ion channel that greatly contributes to the fast integration times in binaural nuclei of the superior olivary complex in other species. This suggests substantially lengthened membrane time constants and thus prolonged temporal integration of inputs in binaural auditory brainstem neurons and might be linked to the severely degenerated sound localization abilities in these animals.

Structural Changes and Lack of HCN1 Channels in the Binaural Auditory Brainstem of the Naked Mole-Rat (Heterocephalus glaber.

Directory of Open Access Journals (Sweden)

Nikodemus Gessele

Full Text Available Naked mole-rats (Heterocephalus glaber live in large eu-social, underground colonies in narrow burrows and are exposed to a large repertoire of communication signals but negligible binaural sound localization cues, such as interaural time and intensity differences. We therefore asked whether monaural and binaural auditory brainstem nuclei in the naked mole-rat are differentially adjusted to this acoustic environment. Using antibody stainings against excitatory and inhibitory presynaptic structures, namely the vesicular glutamate transporter VGluT1 and the glycine transporter GlyT2 we identified all major auditory brainstem nuclei except the superior paraolivary nucleus in these animals. Naked mole-rats possess a well structured medial superior olive, with a similar synaptic arrangement to interaural-time-difference encoding animals. The neighboring lateral superior olive, which analyzes interaural intensity differences, is large and elongated, whereas the medial nucleus of the trapezoid body, which provides the contralateral inhibitory input to these binaural nuclei, is reduced in size. In contrast, the cochlear nucleus, the nuclei of the lateral lemniscus and the inferior colliculus are not considerably different when compared to other rodent species. Most interestingly, binaural auditory brainstem nuclei lack the membrane-bound hyperpolarization-activated channel HCN1, a voltage-gated ion channel that greatly contributes to the fast integration times in binaural nuclei of the superior olivary complex in other species. This suggests substantially lengthened membrane time constants and thus prolonged temporal integration of inputs in binaural auditory brainstem neurons and might be linked to the severely degenerated sound localization abilities in these animals.

Effects of buprofezin on the ultrastructure of the third instar cuticle of the insect Trialeurodes vaporariorum.

Science.gov (United States)

De Cock, A; Degheele, D

1991-01-01

Treatment with buprofezin at the beginning of the third instar of Trialeurodes vaporariorum results in death of the larvae at the time of moulting. Electron microscopic observations, after treatment of the larvae with 20 mg a.i./l buprofezin, does not reveal any difference in the ultrastructural profile before apolysis, however formation of a normal lamellate procuticle is disturbed. The pharate procuticle is amorphous, varying in thickness and the mean thickness is greatly reduced. The subcuticle is interrupted several times at locations corresponding with the thinnest places of the pharate cuticle. Epidermal cells contain unusual structures such as myelin figures and hypertrophied mitochondria indicating that buprofezin may have an additional toxic effect on epidermal cells.

Exploring the interior of cuticles and compressions of fossil plants by FIB-SEM milling and image microscopy.

Science.gov (United States)

Sender, L M; Escapa, I; Benedetti, A; Cúneo, R; Diez, J B

2018-01-01

We present the first study of cuticles and compressions of fossil leaves by Focused Ion Beam Scanning Electron Microscopy (FIB-SEM). Cavities preserved inside fossil leaf compressions corresponding to substomatal chambers have been observed for the first time and several new features were identified in the cross-section cuts. These results open a new way in the investigation of the three-dimensional structures of both micro- and nanostructural features of fossil plants. Moreover, the application of the FIB-SEM technique to both fossils and extant plant remains represent a new source of taxonomical, palaeoenvironmental and palaeoclimatic information. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae.

Directory of Open Access Journals (Sweden)

Matthew J Mason

Full Text Available Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a 'columelliform' stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence.

Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae).

Science.gov (United States)

Mason, Matthew J; Cornwall, Hannah L; Smith, Ewan St J

2016-01-01

Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus) were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a 'columelliform' stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids) reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence.

Large-area, uniform and low-cost dual-mode plasmonic naked-eye colorimetry and SERS sensor with handheld Raman spectrometer.

Science.gov (United States)

Xu, Zhida; Jiang, Jing; Wang, Xinhao; Han, Kevin; Ameen, Abid; Khan, Ibrahim; Chang, Te-Wei; Liu, Gang Logan

2016-03-21

We demonstrated a highly-sensitive, wafer-scale, highly-uniform plasmonic nano-mushroom substrate based on plastic for naked-eye plasmonic colorimetry and surface-enhanced Raman spectroscopy (SERS). We gave it the name FlexBrite. The dual-mode functionality of FlexBrite allows for label-free qualitative analysis by SERS with an enhancement factor (EF) of 10(8) and label-free quantitative analysis by naked-eye colorimetry with a sensitivity of 611 nm RIU(-1). The SERS EF of FlexBrite in the wet state was found to be 4.81 × 10(8), 7 times stronger than in the dry state, making FlexBrite suitable for aqueous environments such as microfluid systems. The label-free detection of biotin-streptavidin interaction by both SERS and colorimetry was demonstrated with FlexBrite. The detection of trace amounts of the narcotic drug methamphetamine in drinking water by SERS was implemented with a handheld Raman spectrometer and FlexBrite. This plastic-based dual-mode nano-mushroom substrate has the potential to be used as a sensing platform for easy and fast analysis in chemical and biological assays.

Novel cellulose-based halochromic test strips for naked-eye detection of alkaline vapors and analytes.

Science.gov (United States)

Abou-Yousef, Hussein; Khattab, Tawfik A; Youssef, Yehia A; Al-Balakocy, Naser; Kamel, Samir

2017-08-01

A simple, portable and highly sensitive naked-eye test strip is successfully prepared for optical detection of gaseous and aqueous alkaline analytes. Novel pH-sensory tricyanofuran-hydrazone (TCFH) disperse colorant containing a hydrazone recognition functional moiety is successfully synthesized via azo-coupling reaction between active methyl-containing tricyanofuran (TCF) heterocycle and diazonium salt of 4-aminobenzaldehyde followed by Knoevenagel condensation with malononitrile. UV-vis absorption spectra display solvatochromism and reversible color changes of the TCFH solution in dimethyl sulfoxide in response to pH variations. We investigate the preparation of hydrophobic cellulose/polyethylene terephthalate composites characterized by their high affinity for disperse dyes. Composite films made from CA, Cell/CA, PET/CA, and Cell/PET-CA are produced via solvent-casting procedure using 10-30% modified cellulose or modified polyethylene terephthalate. The mechanical properties and morphologies of these composite films are investigated. The prepared pH-sensory hydrazone-based disperse dye is then applied to dye the produced cellulose-based composite films employing the high temperature pressure dyeing procedure. The produced halochromic PET-CA-TCFH test strip provide an instant visible signal from orange to purple upon exposure to alkaline conditions as proved by the coloration measurements. The sensor strip exhibits high sensitivity and quick detection toward ammonia in both of aqueous and vapor phases by naked-eye observations at room temperature and atmospheric pressure. Copyright © 2017 Elsevier B.V. All rights reserved.

Perceiving polarization with the naked eye: characterization of human polarization sensitivity

Science.gov (United States)

Temple, Shelby E.; McGregor, Juliette E.; Miles, Camilla; Graham, Laura; Miller, Josie; Buck, Jordan; Scott-Samuel, Nicholas E.; Roberts, Nicholas W.

2015-01-01

Like many animals, humans are sensitive to the polarization of light. We can detect the angle of polarization using an entoptic phenomenon called Haidinger's brushes, which is mediated by dichroic carotenoids in the macula lutea. While previous studies have characterized the spectral sensitivity of Haidinger's brushes, other aspects remain unexplored. We developed a novel methodology for presenting gratings in polarization-only contrast at varying degrees of polarization in order to measure the lower limits of human polarized light detection. Participants were, on average, able to perform the task down to a threshold of 56%, with some able to go as low as 23%. This makes humans the most sensitive vertebrate tested to date. Additionally, we quantified a nonlinear relationship between presented and perceived polarization angle when an observer is presented with a rotatable polarized light field. This result confirms a previous theoretical prediction of how uniaxial corneal birefringence impacts the perception of Haidinger's brushes. The rotational dynamics of Haidinger's brushes were then used to calculate corneal retardance. We suggest that psychophysical experiments, based upon the perception of polarized light, are amenable to the production of affordable technologies for self-assessment and longitudinal monitoring of visual dysfunctions such as age-related macular degeneration. PMID:26136441

Convective Heat Transfer Coefficients of the Human Body under Forced Convection from Ceiling

DEFF Research Database (Denmark)

Kurazumi, Yoshihito; Rezgals, Lauris; Melikov, Arsen Krikor

2014-01-01

The average convective heat transfer coefficient for a seated human body exposed to downward flow from above was determined. Thermal manikin with complex body shape and size of an average Scandinavian female was used. The surface temperature distribution of the manikin’s body was as the skin...... of the convective heat transfer coefficient of the whole body (hc [W/(m2•K)]) was proposed: hc=4.088+6.592V1.715 for a seated naked body at 20ºC and hc=2.874+7.427V1.345 for a seated naked body at 26ºC. Differences in the convective heat transfer coefficient of the whole body in low air velocity range, V

Bilateral lesions of the medial frontal cortex disrupt recognition of social hierarchy during antiphonal communication in naked mole-rats (Heterocephalus glaber).

Science.gov (United States)

Yosida, Shigeto; Okanoya, Kazuo

2012-02-01

Generation of the motor patterns of emotional sounds in mammals occurs in the periaqueductal gray matter of the midbrain and is not directly controlled by the cortex. The medial frontal cortex indirectly controls vocalizations, based on the recognition of social context. We examined whether the medial frontal cortex was responsible for antiphonal vocalization, or turn-taking, in naked mole-rats. In normal turn-taking, naked mole-rats vocalize more frequently to dominant individuals than to subordinate ones. Bilateral lesions of the medial frontal cortex disrupted differentiation of call rates to the stimulus animals, which had varied social relationships to the subject. However, medial frontal cortex lesions did not affect either the acoustic properties of the vocalizations or the timing of the vocal exchanges. This suggests that the medial frontal cortex may be involved in social cognition or decision making during turn-taking, while other regions of the brain regulate when animals vocalize and the vocalizations themselves.

Horizontal gene transfer contributed to the evolution of extracellular surface structures: the freshwater polyp Hydra is covered by a complex fibrous cuticle containing glycosaminoglycans and proteins of the PPOD and SWT (sweet tooth families.

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Angelika Böttger

Full Text Available The single-cell layered ectoderm of the fresh water polyp Hydra fulfills the function of an epidermis by protecting the animals from the surrounding medium. Its outer surface is covered by a fibrous structure termed the cuticle layer, with similarity to the extracellular surface coats of mammalian epithelia. In this paper we have identified molecular components of the cuticle. We show that its outermost layer contains glycoproteins and glycosaminoglycans and we have identified chondroitin and chondroitin-6-sulfate chains. In a search for proteins that could be involved in organising this structure we found PPOD proteins and several members of a protein family containing only SWT (sweet tooth domains. Structural analyses indicate that PPODs consist of two tandem β-trefoil domains with similarity to carbohydrate-binding sites found in lectins. Experimental evidence confirmed that PPODs can bind sulfated glycans and are secreted into the cuticle layer from granules localized under the apical surface of the ectodermal epithelial cells. PPODs are taxon-specific proteins which appear to have entered the Hydra genome by horizontal gene transfer from bacteria. Their acquisition at the time Hydra evolved from a marine ancestor may have been critical for the transition to the freshwater environment.

Review of Naked Statistics: Stripping the Dread from Data by Charles Wheelan

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Michael T. Catalano

2015-01-01

Full Text Available Wheelan, Charles. Naked Statistics: Stripping the Dread from Data (New York, NY, W. W. Norton & Company, 2014. 282 pp. ISBN 978-0-393-07195-5 In his review of What Numbers Say and The Numbers Game, Rob Root (Numeracy 3(1: 9 writes “Popular books on quantitative literacy need to be easy to read, reasonably comprehensive in scope, and include examples that are thought-provoking and memorable.” Wheelan’s book certainly meets this description, and should be of interest to both the general public and those with a professional interest in numeracy. A moderately diligent learner can get a decent understanding of basic statistics from the book. Teachers of statistics and quantitative literacy will find a wealth of well-related examples and stories to use in their classes.

Social condition and oxytocin neuron number in the hypothalamus of naked mole-rats (Heterocephalus glaber).

Science.gov (United States)

Mooney, S J; Holmes, M M

2013-01-29

The naked mole-rat is a subterranean colonial rodent. In each colony, which can grow to as many as 300 individuals, there is only one female and 1-3 males that are reproductive and socially dominant. The remaining animals are reproductively suppressed subordinates that contribute to colony survival through their cooperative behaviors. Oxytocin is a peptide hormone that has shown relatively widespread effects on prosocial behaviors in other species. We examined whether social status affects the number of oxytocin-immunoreactive neurons in the paraventricular nucleus and the supraoptic nucleus by comparing dominant breeding animals to subordinate non-breeding workers from intact colonies. We also examined these regions in subordinate animals that had been removed from their colony and paired with an opposite- or same-sex conspecific for 6 months. Stereological analyses indicated that subordinates had significantly more oxytocin neurons in the paraventricular nucleus than breeders. Animals in both opposite- and same-sex pairs showed a decreased oxytocin neuron number compared to subordinates suggesting that status differences may be due to social condition rather than the reproductive activity of the animal per se. The effects of social status appear to be region specific as no group differences were found for oxytocin neuron number in the supraoptic nucleus. Given that subordinate naked mole-rats are kept reproductively suppressed through antagonism by the queen, we speculate that status differences are due either to oxytocin's anxiolytic properties to combat the stress of this antagonism or to its ability to promote the prosocial behaviors of subordinates. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Chirality-induced polarization effects in the cuticle of scarab beetles: 100 years after Michelson

Science.gov (United States)

Arwin, Hans; Magnusson, Roger; Landin, Jan; Järrendahl, Kenneth

2012-04-01

One hundred years ago Michelson discovered circular polarization in reflection from beetles. Today a novel Mueller-matrix ellipsometry setup allows unprecedented detailed characterization of the beetles' polarization properties. A formalism based on elliptical polarization for description of reflection from scarab beetles is here proposed and examples are given on four beetles of different character: Coptomia laevis - a simple dielectric mirror; Cetonia aurata - a left-hand narrow-band elliptical polarizer; Anoplognathus aureus - a broad-band elliptical polarizer; and Chrysina argenteola - a left-hand polarizer for visible light at small angles, whereas for larger angles, red reflected light is right-handed polarized. We confirm the conclusion of previous studies which showed that a detailed quantification of ellipticity and degree of polarization of cuticle reflection can be performed instead of only determining whether reflections are circularly polarized or not. We additionally investigate reflection as a function of incidence angle. This provides much richer information for understanding the behaviour of beetles and for structural analysis.

Negligible senescence in the longest living rodent, the naked mole-rat: insights from a successfully aging species.

Science.gov (United States)

Buffenstein, Rochelle

2008-05-01

Aging refers to a gradual deterioration in function that, over time, leads to increased mortality risk, and declining fertility. This pervasive process occurs in almost all organisms, although some long-lived trees and cold water inhabitants reportedly show insignificant aging. Negligible senescence is characterized by attenuated age-related change in reproductive and physiological functions, as well as no observable age-related gradual increase in mortality rate. It was questioned whether the longest living rodent, the naked mole-rat, met these three strict criteria. Naked mole-rats live in captivity for more than 28.3 years, approximately 9 times longer than similar-sized mice. They maintain body composition from 2 to 24 years, and show only slight age-related changes in all physiological and morphological characteristics studied to date. Surprisingly breeding females show no decline in fertility even when well into their third decade of life. Moreover, these animals have never been observed to develop any spontaneous neoplasm. As such they do not show the typical age-associated acceleration in mortality risk that characterizes every other known mammalian species and may therefore be the first reported mammal showing negligible senescence over the majority of their long lifespan. Clearly physiological and biochemical processes in this species have evolved to dramatically extend healthy lifespan. The challenge that lies ahead is to understand what these mechanisms are.

Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis

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Barnett Eric

2012-09-01

Full Text Available Abstract Background In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice’s cuticular wax. Methods A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID was used to determine the presence of hydrocarbons in the three head lice extracts. Results In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5 was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Conclusions Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax

Reduced Utilization of Selenium by Naked Mole Rats Due to a Specific Defect in GPx1 Expression*

OpenAIRE

Kasaikina, Marina V.; Lobanov, Alexei V.; Malinouski, Mikalai Y.; Lee, Byung Cheon; Seravalli, Javier; Fomenko, Dmitri E.; Turanov, Anton A.; Finney, Lydia; Vogt, Stefan; Park, Thomas J.; Miller, Richard A.; Hatfield, Dolph L.; Gladyshev, Vadim N.

2011-01-01

Naked mole rat (MR) Heterocephalus glaber is a rodent model of delayed aging because of its unusually long life span (>28 years). It is also not known to develop cancer. In the current work, tissue imaging by x-ray fluorescence microscopy and direct analyses of trace elements revealed low levels of selenium in the MR liver and kidney, whereas MR and mouse brains had similar selenium levels. This effect was not explained by uniform selenium deficiency because methionine sulfoxide reductase act...

Extracellular esterases of phylloplane yeast Pseudozyma antarctica induce defect on cuticle layer structure and water-holding ability of plant leaves.

Science.gov (United States)

Ueda, Hirokazu; Mitsuhara, Ichiro; Tabata, Jun; Kugimiya, Soichi; Watanabe, Takashi; Suzuki, Ken; Yoshida, Shigenobu; Kitamoto, Hiroko

2015-08-01

Aerial plant surface (phylloplane) is a primary key habitat for many microorganisms but is generally recognized as limited in nutrient resources. Pseudozyma antarctica, a nonpathogenic yeast, is commonly isolated from plant surfaces and characterized as an esterase producer with fatty acid assimilation ability. In order to elucidate the biological functions of these esterases, culture filtrate with high esterase activity (crude enzyme) of P. antarctica was applied onto leaves of tomato and Arabidopsis. These leaves showed a wilty phenotype, which is typically associated with water deficiency. Furthermore, we confirmed that crude enzyme-treated detached leaves clearly lost their water-holding ability. In treated leaves of both plants, genes associated to abscisic acid (ABA; a plant stress hormone responding osmotic stress) were activated and accumulation of ABA was confirmed in tomato plants. Microscopic observation of treated leaf surfaces revealed that cuticle layer covering the aerial epidermis of leaves became thinner. A gas chromatography-mass spectrometry (GC-MS) analysis exhibited that fatty acids with 16 and 18 carbon chains were released in larger amounts from treated leaf surfaces, indicating that the crude enzyme has ability to degrade lipid components of cuticle layer. Among the three esterases detected in the crude enzyme, lipase A, lipase B, and P. antarctica esterase (PaE), an in vitro enzyme assay using para-nitrophenyl palmitate as substrate demonstrated that PaE was the most responsible for the degradation. These results suggest that PaE has a potential role in the extraction of fatty acids from plant surfaces, making them available for the growth of phylloplane yeasts.

The long gestation of the small naked mole-rat (Heterocephalus glaber Ruppell, 1842 studied with ultrasound biomicroscopy and 3D-ultrasonography.

Directory of Open Access Journals (Sweden)

Kathleen Roellig

Full Text Available The naked mole-rat (Heterocephalus glaber is one of the two known mammalian species that live in a eusocial population structure. Here we investigate the exceptionally long gestation period of 70 days observed in the mole-rat queen. The course of seven successful pregnancies in two individuals was recorded in a colony of captive naked mole-rats using ultrasound biomicroscopy (UBM and 3D-ultrasonography. We establish a catalogue of basic reference ultrasound data for this species by describing the ultrasonographic appearance of reproductive organs, calculating growth curves to predict gestational age and defining ultrasonographic milestones to characterize pregnancy stages. Mean litter size was 10.9±2.7, of which 7.2±1.5 survived the weaning period. Mean interbirth interval was 128.8±63.0 days. The reproductive success in our colony did not differ from previously published data. In the queen the active corpora lutea had an anechoic, fluid filled centre. Using UBM, pregnancy could be detected 53 days before parturition. The period of embryonic development is assumed to last until 30 days before parturition. Embryonic resorptions were detected frequently in the queen, indicating that this might be an ordinary event in this species. We discuss the extraordinary long gestation period of this small rodent and postulate that the long gestation is beneficial to both the eusocial structure and longevity. An increased litter size, twice as large as for other rodents of similar size, seemingly compensates for the doubling of pregnancy length. We demonstrate that the lifetime reproductive effort of a naked mole-rat queen is equivalent to the mass of offspring that would be produced if all of the females of a colony would be reproducing.

An ion beam deceleration lens for ultra-low-energy ion bombardment of naked DNA

Energy Technology Data Exchange (ETDEWEB)

Thopan, P.; Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuldyuld@gmail.com [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

2013-07-15

Highlights: ► An ion beam deceleration lens was designed and constructed. ► The deceleration lens was installed and tested. ► The decelerated ion beam energy was measured using an electrical field. ► Decelerated ultra-low-energy ion beam bombarded naked DNA. ► Ion beam with energy of a few tens of eV could break DNA strands. -- Abstract: Study of low-energy ion bombardment effect on biological living materials is of significance. High-energy ion beam irradiation of biological materials such as organs and cells has no doubt biological effects. However, ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range. To investigate effects from very-low-energy ion bombardment on biological materials, an ion beam deceleration lens is necessary for uniform ion energy lower than keV. A deceleration lens was designed and constructed based on study of the beam optics using the SIMION program. The lens consisted of six electrodes, able to focus and decelerate primary ion beam, with the last one being a long tube to obtain a parallel uniform exiting beam. The deceleration lens was installed to our 30-kV bioengineering-specialized ion beam line. The final decelerated-ion energy was measured using a simple electrostatic field to bend the beam to range from 10 eV to 1 keV controlled by the lens parameters and the primary beam condition. In a preliminary test, nitrogen ion beam at 60 eV decelerated from a primary 20-keV beam bombarded naked plasmid DNA. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks. The study demonstrated that the ion bombardment with energy as low as several-tens eV was possible to break DNA strands and thus potential to cause genetic modification of biological cells.

An ion beam deceleration lens for ultra-low-energy ion bombardment of naked DNA

International Nuclear Information System (INIS)

Thopan, P.; Prakrajang, K.; Thongkumkoon, P.; Suwannakachorn, D.; Yu, L.D.

2013-01-01

Highlights: ► An ion beam deceleration lens was designed and constructed. ► The deceleration lens was installed and tested. ► The decelerated ion beam energy was measured using an electrical field. ► Decelerated ultra-low-energy ion beam bombarded naked DNA. ► Ion beam with energy of a few tens of eV could break DNA strands. -- Abstract: Study of low-energy ion bombardment effect on biological living materials is of significance. High-energy ion beam irradiation of biological materials such as organs and cells has no doubt biological effects. However, ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range. To investigate effects from very-low-energy ion bombardment on biological materials, an ion beam deceleration lens is necessary for uniform ion energy lower than keV. A deceleration lens was designed and constructed based on study of the beam optics using the SIMION program. The lens consisted of six electrodes, able to focus and decelerate primary ion beam, with the last one being a long tube to obtain a parallel uniform exiting beam. The deceleration lens was installed to our 30-kV bioengineering-specialized ion beam line. The final decelerated-ion energy was measured using a simple electrostatic field to bend the beam to range from 10 eV to 1 keV controlled by the lens parameters and the primary beam condition. In a preliminary test, nitrogen ion beam at 60 eV decelerated from a primary 20-keV beam bombarded naked plasmid DNA. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks. The study demonstrated that the ion bombardment with energy as low as several-tens eV was possible to break DNA strands and thus potential to cause genetic modification of biological cells

Covalently bound DNA on naked iron oxide nanoparticles: Intelligent colloidal nano-vector for cell transfection.

Science.gov (United States)

Magro, Massimiliano; Martinello, Tiziana; Bonaiuto, Emanuela; Gomiero, Chiara; Baratella, Davide; Zoppellaro, Giorgio; Cozza, Giorgio; Patruno, Marco; Zboril, Radek; Vianello, Fabio

2017-11-01

Conversely to common coated iron oxide nanoparticles, novel naked surface active maghemite nanoparticles (SAMNs) can covalently bind DNA. Plasmid (pDNA) harboring the coding gene for GFP was directly chemisorbed onto SAMNs, leading to a novel DNA nanovector (SAMN@pDNA). The spontaneous internalization of SAMN@pDNA into cells was compared with an extensively studied fluorescent SAMN derivative (SAMN@RITC). Moreover, the transfection efficiency of SAMN@pDNA was evaluated and explained by computational model. SAMN@pDNA was prepared and characterized by spectroscopic and computational methods, and molecular dynamic simulation. The size and hydrodynamic properties of SAMN@pDNA and SAMN@RITC were studied by electron transmission microscopy, light scattering and zeta-potential. The two nanomaterials were tested by confocal scanning microscopy on equine peripheral blood-derived mesenchymal stem cells (ePB-MSCs) and GFP expression by SAMN@pDNA was determined. Nanomaterials characterized by similar hydrodynamic properties were successfully internalized and stored into mesenchymal stem cells. Transfection by SAMN@pDNA occurred and GFP expression was higher than lipofectamine procedure, even in the absence of an external magnetic field. A computational model clarified that transfection efficiency can be ascribed to DNA availability inside cells. Direct covalent binding of DNA on naked magnetic nanoparticles led to an extremely robust gene delivery tool. Hydrodynamic and chemical-physical properties of SAMN@pDNA were responsible of the successful uptake by cells and of the efficiency of GFP gene transfection. SAMNs are characterized by colloidal stability, excellent cell uptake, persistence in the host cells, low toxicity and are proposed as novel intelligent DNA nanovectors for efficient cell transfection. Copyright © 2017 Elsevier B.V. All rights reserved.

The effects of oxotremorine, epibatidine, atropine, mecamylamine and naloxone in the tail-flick, hot-plate, and formalin tests in the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Dulu, Thomas D; Kanui, Titus I; Towett, Philemon K; Maloiy, Geoffrey M; Abelson, Klas S P

2014-01-01

The naked mole-rat (Heterocephalus glaber) is a promising animal model for the study of pain mechanisms, therefore a thorough characterization of this species is essential. The aim of the present study was to establish the naked mole-rat as a model for studying the cholinergic receptor system in antinociception by investigating the involvement of muscarinic, nicotinic and opioid receptors in nociceptive tests in this species. The effects of systemic administration of the muscarinic receptor agonist oxotremorine and the nicotinic receptor agonist epibatidine were investigated in the tail-flick, the hot-plate, and the formalin tests. The effects of co-administration of the muscarinic receptor antagonist atropine, the nicotinic receptor antagonist mecamylamine, and the opioid receptor antagonist naloxone were also investigated. Oxotremorine and epibatidine induced a significant, dose-dependent antinociceptive effect in the tail-flick, hot-plate, and formalin tests, respectively. The effects of oxotremorine and epibatidine were blocked by atropine and mecamylamine, respectively. In all three nociceptive tests, naloxone in combination with oxotremorine or epibatidine enhanced the antinociceptive effects of the drugs. The present study demonstrated that stimulation of muscarinic and nicotinic receptors produces antinociceptive effects in the naked-mole rat. The reversal effect of atropine and mecamylamine suggests that this effect is mediated by cholinergic receptors. As naloxone increases the antinociceptive effects of cholinergic agonists, it is suggested that the cholinergic antinociception acts via a gateway facilitated by opioid receptor blockage; however, the precise interaction between these receptor systems needs further investigation.

ENERGETIC VALUE OF FORAGES FROM SEMI-ARID REGION AND DIGESTIBILITY OF RATIONS FOR NAKED NECK PULLETS

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ALEX MARTINS VARELA DE ARRUDA

2014-01-01

Full Text Available The feeding programs for naked neck chickens in semi-intensive production system from brazilian equatorial semi-arid environment, must consider regional food availability and respective nutritional values. Thus, to evaluate the digestibility and metabolizable energy of alternative forages, it was used 240 naked neck pullets (Isa Label lineage receiving water and ration ad libitum, pair-housed in cages for total collection of excreta on conventional warehouse. It was used a completely randomized design with factorial arrangement (5x2: one control ration (corn and soy meal and other four experimental rations with silk flower hay (Calotropis procera, cassava leafs hay (Manihot esculenta, kills pasture hay (Senna obtusifolia or leucaena leafs hay (Leucaena leucocephala, and all rations were balanced for two growing phases, between 8 and 10 weeks (young pullets and between 14 and 16 weeks of age (old pullets. The values of apparent digestibility of nutrients for all experimental rations were lower than control ration (P <0.05 and it was observed general means of 72.18% for dry matter, 78.12% for crude protein, 66.90% for ether extract, 28.08% for neutral detergent fiber, 18.51% for the acid detergent fiber, 71.64% for gross energy and availability of 15.61% for mineral matter. The general mean of apparent and corrected metabolizable energy of alternative forages was 1217 kcal/ kg and 1108 kcal/kg, respectively, and the higher value was determined for leucaena hay and the lower value for silk flower hay (P <0.05.

Analysis of internal structure changes in black human hair keratin fibers resulting from bleaching treatments using Raman spectroscopy

Science.gov (United States)

Kuzuhara, Akio

2013-09-01

In order to investigate in detail the internal structure changes in virgin black human hair keratin fibers resulting from bleaching treatments, the structure of cross-sections at various depths of black human hair, which had been impossible due to high melanin grande content, was directly analyzed using Raman spectroscopy. The gauche-gauche-gauche (GGG) content of the sbnd SSsbnd groups existing from the cuticle region to the center of cortex region of the virgin black human hair remarkably decreased, while the gauche-gauche-trans and trans-gauche-trans contents were not changed by performing the excessive bleaching treatment. In particular, it was found that not only the β-sheet and/or random coil content, but also the α-helix content existing throughout the cortex region of virgin black human hair decreased. In addition, the transmission electron microscope observation shows that the proteins in the cell membrane complex, the cuticle and cortex of the virgin black human hair were remarkably eluted by performing the excessive bleaching treatment. From these experiments, the author concluded that the sbnd SSsbnd groups, which have a GGG conformation were decomposed and finally converted to cysteic acid, and the α-helix structure of some of the proteins existing in the keratin was changed to the random coil structure, or eluted from the cortex region, thereby leading to the reduction in the protein density of the virgin human hair after the excessive bleaching treatment.

Low-Dose Gene Therapy for Murine PKU Using Episomal Naked DNA Vectors Expressing PAH from Its Endogenous Liver Promoter

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Hiu Man Grisch-Chan

2017-06-01

Full Text Available Limited duration of transgene expression, insertional mutagenesis, and size limitations for transgene cassettes pose challenges and risk factors for many gene therapy vectors. Here, we report on physiological expression of liver phenylalanine hydroxylase (PAH by delivery of naked DNA/minicircle (MC-based vectors for correction of homozygous enu2 mice, a model of human phenylketonuria (PKU. Because MC vectors lack a defined size limit, we constructed a MC vector expressing a codon-optimized murine Pah cDNA that includes a truncated intron and is under the transcriptional control of a 3.6-kb native Pah promoter/enhancer sequence. This vector, delivered via hydrodynamic injection, yielded therapeutic liver PAH activity and sustained correction of blood phenylalanine comparable to viral or synthetic liver promoters. Therapeutic efficacy was seen with vector copy numbers of 95% loss of vector genomes and PAH activity in liver, demonstrating that MC vectors had not integrated into the liver genome. In conclusion, MC vectors, which do not have a defined size-limitation, offer a favorable safety profile for hepatic gene therapy due to their non-integration in combination with native promoters.

Specific paucity of unmyelinated C-fibers in cutaneous peripheral nerves of the African naked-mole rat: comparative analysis using six species of Bathyergidae.

Science.gov (United States)

St John Smith, Ewan; Purfürst, Bettina; Grigoryan, Tamara; Park, Thomas J; Bennett, Nigel C; Lewin, Gary R

2012-08-15

In mammalian peripheral nerves, unmyelinated C-fibers usually outnumber myelinated A-fibers. By using transmission electron microscopy, we recently showed that the saphenous nerve of the naked mole-rat (Heterocephalus glaber) has a C-fiber deficit manifested as a substantially lower C:A-fiber ratio compared with other mammals. Here we determined the uniqueness of this C-fiber deficit by performing a quantitative anatomical analysis of several peripheral nerves in five further members of the Bathyergidae mole-rat family: silvery (Heliophobius argenteocinereus), giant (Fukomys mechowii), Damaraland (Fukomys damarensis), Mashona (Fukomys darlingi), and Natal (Cryptomys hottentotus natalensis) mole-rats. In the largely cutaneous saphenous and sural nerves, the naked mole-rat had the lowest C:A-fiber ratio (∼1.5:1 compared with ∼3:1), whereas, in nerves innervating both skin and muscle (common peroneal and tibial) or just muscle (lateral/medial gastrocnemius), this pattern was mostly absent. We asked whether lack of hair follicles alone accounts for the C-fiber paucity by using as a model a mouse that loses virtually all its hair as a consequence of conditional deletion of the β-catenin gene in the skin. These β-catenin loss-of function mice (β-cat LOF mice) displayed only a mild decrease in C:A-fiber ratio compared with wild-type mice (4.42 compared with 3.81). We suggest that the selective cutaneous C-fiber deficit in the cutaneous nerves of naked mole-rats is unlikely to be due primarily to lack of skin hair follicles. Possible mechanisms contributing to this unique peripheral nerve anatomy are discussed. Copyright © 2012 Wiley Periodicals, Inc.

The long gestation of the small naked mole-rat (Heterocephalus glaber Rüppell, 1842) studied with ultrasound biomicroscopy and 3D-ultrasonography.

Science.gov (United States)

Roellig, Kathleen; Drews, Barbara; Goeritz, Frank; Hildebrandt, Thomas Bernd

2011-03-07

The naked mole-rat (Heterocephalus glaber) is one of the two known mammalian species that live in a eusocial population structure. Here we investigate the exceptionally long gestation period of 70 days observed in the mole-rat queen. The course of seven successful pregnancies in two individuals was recorded in a colony of captive naked mole-rats using ultrasound biomicroscopy (UBM) and 3D-ultrasonography. We establish a catalogue of basic reference ultrasound data for this species by describing the ultrasonographic appearance of reproductive organs, calculating growth curves to predict gestational age and defining ultrasonographic milestones to characterize pregnancy stages. Mean litter size was 10.9±2.7, of which 7.2±1.5 survived the weaning period. Mean interbirth interval was 128.8±63.0 days. The reproductive success in our colony did not differ from previously published data. In the queen the active corpora lutea had an anechoic, fluid filled centre. Using UBM, pregnancy could be detected 53 days before parturition. The period of embryonic development is assumed to last until 30 days before parturition. Embryonic resorptions were detected frequently in the queen, indicating that this might be an ordinary event in this species. We discuss the extraordinary long gestation period of this small rodent and postulate that the long gestation is beneficial to both the eusocial structure and longevity. An increased litter size, twice as large as for other rodents of similar size, seemingly compensates for the doubling of pregnancy length. We demonstrate that the lifetime reproductive effort of a naked mole-rat queen is equivalent to the mass of offspring that would be produced if all of the females of a colony would be reproducing.

A genetic linkage map of hexaploid naked oat constructed with SSR markers

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Gaoyuan Song

2015-08-01

Full Text Available Naked oat is a unique health food crop in China. Using 202 F2 individuals derived from a hybrid between the variety 578 and the landrace Sanfensan, we constructed a genetic linkage map consisting of 22 linkage groups covering 2070.50 cM and including 208 simple sequence repeat (SSR markers. The minimum distance between adjacent markers was 0.01 cM and the average was 9.95 cM. Each linkage group contained 2–22 markers. The largest linkage group covered 174.40 cM and the shortest one covered 36.80 cM, with an average of 94.11 cM. Thirty-six markers (17.3% showing distorted segregation were distributed across linkage groups LG5 to LG22. This map complements published oat genetic maps and is applicable for quantitative trait locus analysis, gene cloning and molecular marker-assisted selection.

AFM friction and adhesion mapping of the substructures of human hair cuticles

International Nuclear Information System (INIS)

Smith, James R.; Tsibouklis, John; Nevell, Thomas G.; Breakspear, Steven

2013-01-01

Using atomic force microscopy, values of the microscale friction coefficient, the tip (silicon nitride) - surface adhesion force and the corresponding adhesion energy, for the substructures that constitute the surface of human hair (European brown hair) have been determined from Amonton plots. The values, mapped for comparison with surface topography, corresponded qualitatively with the substructures’ plane surface characteristics. Localised maps and values of the frictional coefficient, extracted avoiding scale edge effects, are likely to inform the formulation of hair-care products and treatments.

Interrelation between the Author and the Text in W. S. Burroughs’s Naked Lunch and Chuck Palahniuk’s Fight Club

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Viktoria Grivina

2014-11-01

Full Text Available Article adopts Jacques Lacan’s concept of the “mirror stage” to study the mechanisms of the way the Author’s identity evolves in W. Burroughs’s Naked Lunch and Ch. Palahniuk’s Fight Club. Evolution of the Author is set against general process of personal growth. The study is primarily concerned with features of the Author’s evolution within transgressive fiction, as Chuck Palahniuk and William Burroughs are the key figures of this genre. Transgression presupposes addressing social taboos by explicating them, thus creating strong reactions within the readership. We argue and find evidence that Burroughs and Palahniuk in the process of facing their perfect images of the Author digress from what Lacan would consider normal development. When they are given a chance to produce a unified body of text, the writers chose unconscious strive for fragmentation instead. Fragmented images invade Naked Lunch and Fight Club. However the mirror stage in the case of Palahniuk and in the case of Burroughs differ. While Burroughs in the myth of the Interzone ends up rejecting the notion of unique Author as such, Palahniuk accepts the fact that he managed to form a new niche for transgressive fiction and stays true to this niche, continuing similar aesthetics in the works that follow.

Subcaste differences in neural activation suggest a prosocial role for oxytocin in eusocial naked mole-rats.

Science.gov (United States)

Hathaway, Georgia A; Faykoo-Martinez, Mariela; Peragine, Deane E; Mooney, Skyler J; Holmes, Melissa M

2016-03-01

The neuropeptide oxytocin (OT) influences prosocial behavior(s), aggression, and stress responsiveness, and these diverse effects are regulated in a species- and context-specific manner. The naked mole-rat (Heterocephalus glaber) is a unique species with which to study context-dependent effects of OT, exhibiting a strict social hierarchy with behavioral specialization within the subordinate caste: soldiers are aggressive and defend colonies against unfamiliar conspecifics while workers are prosocial and contribute to in-colony behaviors such as pup care. To determine if OT is involved in subcaste-specific behaviors, we compared behavioral responses between workers and soldiers of both sexes during a modified resident/intruder paradigm, and quantified activation of OT neurons in the hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON) using the immediate-early-gene marker c-fos co-localized with OT neurons. Resident workers and soldiers were age-matched with unfamiliar worker stimulus animals as intruders, and encounters were videorecorded and scored for aggressive behaviors. Colony-matched controls were left in their home colony for the duration of the encounters. Brains were extracted and cell counts were conducted for OT immunoreactive (ir), c-fos-ir, and percentage of OT-c-fos double-labeled cells. Results indicate that resident workers were less aggressive but showed greater OT neural activity than soldiers. Furthermore, a linear model including social treatment, cortisol, and subcaste revealed that subcaste was the only significant predictor of OT-c-fos double-labeled cells in the PVN. These data suggest that in naked mole-rats OT promotes prosocial behaviors rather than aggression and that even within subordinates status exerts robust effects on brain and behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

First 10 kg of naked germanium detectors installed in liquid nitrogen in GENIUS Test-Facility in GRAN-SASSO

Energy Technology Data Exchange (ETDEWEB)

Klapdor-Kleingrothaus, H.V. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

2004-07-01

The GENIUS Test Facility has come into operation in Gran Sasso on May 5, 2003 with its first ten kg of naked Ge detectors in liquid nitrogen. This is the first time that this novel technique for extreme background reduction in search for rare decays is applied under the background conditions of an underground laboratory. GENIUS-TF has the potential to check the DAMA evidence for cold dark matter by modulation, and possibly, to improve the accuracy of the recently observed first signal for neutrinoless double beta decay. (orig.)

First 10 kg of naked germanium detectors installed in liquid nitrogen in GENIUS Test-Facility in GRAN-SASSO

International Nuclear Information System (INIS)

Klapdor-Kleingrothaus, H.V.

2004-01-01

The GENIUS Test Facility has come into operation in Gran Sasso on May 5, 2003 with its first ten kg of naked Ge detectors in liquid nitrogen. This is the first time that this novel technique for extreme background reduction in search for rare decays is applied under the background conditions of an underground laboratory. GENIUS-TF has the potential to check the DAMA evidence for cold dark matter by modulation, and possibly, to improve the accuracy of the recently observed first signal for neutrinoless double beta decay. (orig.)

X-ray sources in regions of star formation. I. The naked T Tauri stars

International Nuclear Information System (INIS)

Walter, F.M.

1986-01-01

Einstein X-ray observations of regions of active star formation in Taurus, Ophiuchus, and Corona Australis show a greatly enhanced surface density of stellar X-ray sources over that seen in other parts of the sky. Many of the X-ray sources are identified with low-mass, pre-main-sequence stars which are not classical T Tauri stars. The X-ray, photometric, and spectroscopic data for these stars are discussed. Seven early K stars in Oph and CrA are likely to be 1-solar-mass post-T Tauri stars with ages of 10-million yr. The late K stars in Taurus are not post-T Tauri, but naked T Tauri stars, which are coeval with the T Tauri stars, differing mainly in the lack of a circumstellar envelope. 72 references

The initial value problem for linearized gravitational perturbations of the Schwarzschild naked singularity

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Dotti, Gustavo; Gleiser, Reinaldo J [Facultad de Matematica, AstronomIa y Fisica (FaMAF), Universidad Nacional de Cordoba, Ciudad Universitaria, 5000 Cordoba (Argentina)

2009-11-07

The coupled equations for the scalar modes of the linearized Einstein equations around Schwarzschild's spacetime were reduced by Zerilli to a (1+1) wave equation partial deriv{sup 2}PSI{sub z} /partial derivt{sup 2} +HPSI{sub z} =0, where H= -partial deriv{sup 2} /partial derivx{sup 2} + V(x) is the Zerilli 'Hamiltonian' and x is the tortoise radial coordinate. From its definition, for smooth metric perturbations the field PSI{sub z} is singular at r{sub s} = -6M/(l - 1)(l +2), with l being the mode harmonic number. The equation PSI{sub z} obeys is also singular, since V has a second-order pole at r{sub s}. This is irrelevant to the black hole exterior stability problem, where r > 2M > 0, and r{sub s} < 0, but it introduces a non-trivial problem in the naked singular case where M < 0, then r{sub s} > 0, and the singularity appears in the relevant range of r (0 < r < infinity). We solve this problem by developing a new approach to the evolution of the even mode, based on a new gauge invariant function, PSI-circumflex, that is a regular function of the metric perturbation for any value of M. The relation of PSI-circumflex to PSI{sub z} is provided by an intertwiner operator. The spatial pieces of the (1 + 1) wave equations that PSI-circumflex and PSI{sub z} obey are related as a supersymmetric pair of quantum Hamiltonians H and H-circumflex. For M < 0,H-circumflex has a regular potential and a unique self-adjoint extension in a domain D defined by a physically motivated boundary condition at r = 0. This allows us to address the issue of evolution of gravitational perturbations in this non-globally hyperbolic background. This formulation is used to complete the proof of the linear instability of the Schwarzschild naked singularity, by showing that a previously found unstable mode belongs to a complete basis of H-circumflex in D, and thus is excitable by generic initial data. This is further illustrated by numerically solving the linearized equations for

Microbial Populations in Naked Neck Chicken Ceca Raised on Pasture Flock Fed with Commercial Yeast Cell Wall Prebiotics via an Illumina MiSeq Platform.

Directory of Open Access Journals (Sweden)

Si Hong Park

Full Text Available Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer's yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1 C: control (no prebiotic, 2 T1: Biolex® MB40 with 0.2%, and 3 T2: Leiber® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex® MB40 group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS, microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds.

Microbial Populations in Naked Neck Chicken Ceca Raised on Pasture Flock Fed with Commercial Yeast Cell Wall Prebiotics via an Illumina MiSeq Platform.

Science.gov (United States)

Park, Si Hong; Lee, Sang In; Ricke, Steven C

2016-01-01

Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs) and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer's yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1) C: control (no prebiotic), 2) T1: Biolex® MB40 with 0.2%, and 3) T2: Leiber® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex® MB40) group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS), microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds.

Observations of a human hair shaft with an x-ray microscope

Energy Technology Data Exchange (ETDEWEB)

Youn, Hwa Shik [Pohang Accelerator Laboratory, Pohang University of Science and Technology, 31 San, Hyoja-dong, Pohang, KyungBuk, 790-784 (Korea, Republic of); Jung, Suk-Won [Nano Mechatronics Research Center, Korea Electronics Technology Institute, 455-6 Masan-ri, Jinwi-myon, Pyungtaek, Kyungki-do, 451-865 (Korea, Republic of)

2005-11-21

We observed the internal structures of a human hair shaft using x-ray microscopes with a spatial resolution in the range from a few microns to less than 100 nm. The energy of the x-ray used is 6.95 keV. The Zernike phase contrast together with a spatial resolution better than 100 nm enabled us to see the cuticles of scales, the cortex of macrofibrils and the medulla. All these internal features and more can easily be observed with no sample preparation including staining.

Observations of a human hair shaft with an x-ray microscope

International Nuclear Information System (INIS)

Youn, Hwa Shik; Jung, Suk-Won

2005-01-01

We observed the internal structures of a human hair shaft using x-ray microscopes with a spatial resolution in the range from a few microns to less than 100 nm. The energy of the x-ray used is 6.95 keV. The Zernike phase contrast together with a spatial resolution better than 100 nm enabled us to see the cuticles of scales, the cortex of macrofibrils and the medulla. All these internal features and more can easily be observed with no sample preparation including staining

Resistance to experimental tumorigenesis in cells of a long-lived mammal, the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Liang, Sitai; Mele, James; Wu, Yuehong; Buffenstein, Rochelle; Hornsby, Peter J

2010-08-01

The naked mole-rat (NMR, Heterocephalus glaber) is a long-lived mammal in which spontaneous cancer has not been observed. To investigate possible mechanisms for cancer resistance in this species, we studied the properties of skin fibroblasts from the NMR following transduction with oncogenes that cause cells of other mammalian species to form malignant tumors. Naked mole-rat fibroblasts were transduced with a retrovirus encoding SV40 large T antigen and oncogenic Ras(G12V). Following transplantation of transduced cells into immunodeficient mice, cells rapidly entered crisis, as evidenced by the presence of anaphase bridges, giant cells with enlarged nuclei, multinucleated cells, and cells with large number of chromosomes or abnormal chromatin material. In contrast, similarly transduced mouse and rat fibroblasts formed tumors that grew rapidly without crisis. Crisis was also observed after > 40 population doublings in SV40 TAg/Ras-expressing NMR cells in culture. Crisis in culture was prevented by additional infection of the cells with a retrovirus encoding hTERT (telomerase reverse transcriptase). SV40 TAg/Ras/hTERT-expressing NMR cells formed tumors that grew rapidly in immunodeficient mice without evidence of crisis. Crisis could also be induced in SV40 TAg/Ras-expressing NMR cells by loss of anchorage, but after hTERT transduction, cells were able to proliferate normally following loss of anchorage. Thus, rapid crisis is a response of oncogene-expressing NMR cells to growth in an in vivo environment, which requires anchorage independence, and hTERT permits cells to avoid crisis and to achieve malignant tumor growth. The unique reaction of NMR cells to oncogene expression may form part of the cancer resistance of this species.

The effect of irradiation dose and storage time on the ESR signal in the cuticle of different components of the exoskeleton of Norway lobster (Nephrops norvegicus)

Energy Technology Data Exchange (ETDEWEB)

Stewart, E.M. (Queen' s Univ., Belfast, Northern Ireland (United Kingdom)); Stevenson, M.H. (Department of Agriculture for Northern Ireland (United Kingdom). Food and Agricultural Chemistry Research Div. Queen' s Univ., Belfast, Northern Ireland (United Kingdom)); Gray, R. (Department for Agriculture for Northern Ireland (United Kingdom). Food and Agricultural Chemistry Research Div.)

This paper examines the potential of ESR spectroscopy too determine if Norway lobsters have been irradiated. Ninety samples, each containing 3 whole Norway lobsters, were prepared, thirty were used as controls while the remaining sixty were given irradiation doses of approximately either 1 or 3 kGy. Following irradiation the samples were stored at 1[sup o]C for 0, 7, 14, 21 or 28 d. After each storage period the cuticle of the tail, carapace, claws and walking legs was removed, freeze-dried and ground prior to analysis using ESR spectroscopy. The control spectra were subtracted from their respective irradiated spectra thereby leaving the radiation-induced signal. Peak heights of the signals were measured. The ESR signals derived from the different components of the exoskeleton were similar in shape and varied only in their intensities. The claw samples gave the most intense signal while that from the walking legs was the weakest. There was a significant decay in the signal intensity over the storage period with the signal derived from cuticle of the claws showing the greatest diminution (44%) and that of the tail the least (17%). The signal intensities of the walking legs and carapace decreased by 22% and 30% respectively. In conclusion ESR spectroscopy is a useful technique for the qualitative detection of irradiated Norway lobster and shows considerable potential for quantification of dose received. (author).

The effect of irradiation dose and storage time on the ESR signal in the cuticle of different components of the exoskeleton of Norway lobster (Nephrops norvegicus)

International Nuclear Information System (INIS)

Stewart, E.M.; Stevenson, M.H.; Gray, R.

1993-01-01

This paper examines the potential of ESR spectroscopy too determine if Norway lobsters have been irradiated. Ninety samples, each containing 3 whole Norway lobsters, were prepared, thirty were used as controls while the remaining sixty were given irradiation doses of approximately either 1 or 3 kGy. Following irradiation the samples were stored at 1 o C for 0, 7, 14, 21 or 28 d. After each storage period the cuticle of the tail, carapace, claws and walking legs was removed, freeze-dried and ground prior to analysis using ESR spectroscopy. The control spectra were subtracted from their respective irradiated spectra thereby leaving the radiation-induced signal. Peak heights of the signals were measured. The ESR signals derived from the different components of the exoskeleton were similar in shape and varied only in their intensities. The claw samples gave the most intense signal while that from the walking legs was the weakest. There was a significant decay in the signal intensity over the storage period with the signal derived from cuticle of the claws showing the greatest diminution (44%) and that of the tail the least (17%). The signal intensities of the walking legs and carapace decreased by 22% and 30% respectively. In conclusion ESR spectroscopy is a useful technique for the qualitative detection of irradiated Norway lobster and shows considerable potential for quantification of dose received. (author)

Naked Mole Rat Cells Have a Stable Epigenome that Resists iPSC Reprogramming

Directory of Open Access Journals (Sweden)

Li Tan

2017-11-01

Full Text Available Naked mole rat (NMR is a valuable model for aging and cancer research due to its exceptional longevity and cancer resistance. We observed that the reprogramming efficiency of NMR fibroblasts in response to OSKM was drastically lower than that of mouse fibroblasts. Expression of SV40 LargeT antigen (LT dramatically improved reprogramming of NMR fibroblasts. Inactivation of Rb alone, but not p53, was sufficient to improve reprogramming efficiency, suggesting that NMR chromatin may be refractory to reprogramming. Analysis of the global histone landscape revealed that NMR had higher levels of repressive H3K27 methylation marks and lower levels of activating H3K27 acetylation marks than mouse. ATAC-seq revealed that in NMR, promoters of reprogramming genes were more closed than mouse promoters, while expression of LT led to massive opening of the NMR promoters. These results suggest that NMR displays a more stable epigenome that resists de-differentiation, contributing to the cancer resistance and longevity of this species.

Magnetic purification of curcumin from Curcuma longa rhizome by novel naked maghemite nanoparticles.

Science.gov (United States)

Magro, Massimiliano; Campos, Rene; Baratella, Davide; Ferreira, Maria Izabela; Bonaiuto, Emanuela; Corraducci, Vittorino; Uliana, Maíra Rodrigues; Lima, Giuseppina Pace Pereira; Santagata, Silvia; Sambo, Paolo; Vianello, Fabio

2015-01-28

Naked maghemite nanoparticles, namely, surface active maghemite nanoparticles (SAMNs), characterized by a diameter of about 10 nm, possessing peculiar colloidal stability, surface chemistry, and superparamagnetism, present fundamental requisites for the development of effective magnetic purification processes for biomolecules in complex matrices. Polyphenolic molecules presenting functionalities with different proclivities toward iron chelation were studied as probes for testing SAMN suitability for magnetic purification. Thus, the binding efficiency and reversibility on SAMNs of phenolic compounds of interest in the pharmaceutical and food industries, namely, catechin, tyrosine, hydroxytyrosine, ferulic acid, coumaric acid, rosmarinic acid, naringenin, curcumin, and cyanidin-3-glucoside, were evaluated. Curcumin emerged as an elective compound, suitable for magnetic purification by SAMNs from complex matrices. A combination of curcumin, demethoxycurcumin, and bis-demethoxycurcumin was recovered by a single magnetic purification step from extracts of Curcuma longa rhizomes, with a purity >98% and a purification yield of 45%, curcumin being >80% of the total purified curcuminoids.

Theoretical paper: exploring overlooked natural mitochondria-rejuvenative intervention: the puzzle of bowhead whales and naked mole rats.

Science.gov (United States)

Prokopov, Arkadi F

2007-12-01

There is an imperative need for exploring and implementing mitochondria-rejuvenative interventions that can bridge the current gap toward the step-by step realization of strategies for engineered negligible senescence (SENS) agenda. Recently discovered in mammals, natural mechanism mitoptosis-a selective "suicide" of mutated mitochondria-can facilitate continuous purification of mitochondrial pool in an organism from the most reactive oxygen species (ROS)-producing mitochondria. Mitoptosis, which is considered to be the first stage of ROS-induced apoptosis, underlies follicular atresia (a "quality control" mechanism in female germline cells that eliminates most germinal follicles in female embryos). Mitoptosis can be also activated in adult postmitotic somatic cells by evolutionary conserved phenotypic adaptations to intermittent oxygen restriction (IOR) and synergistically acting intermittent caloric restriction (ICR). IOR and ICR are common in mammals and seem to underlie extraordinary longevity and augmented cancer resistance in bowhead whales (Balena mysticetus) and naked mole rats (Heterocephalus glaber). Furthermore, in mammals IOR can facilitate continuous stromal stem cells-de-pendent tissue repair. A comparative analysis of IOR and ICR mechanisms in both mammals, in conjunction with the experience of decades of biomedical and clinical research on emerging preventative, therapeutic, and rehabilitative modality-the intermittent hypoxic training/therapy (IHT)-indicates that the notable clinical efficiency of IHT is based on the universal adaptational mechanisms that are common in mammals. Further exploration of natural mitochondria-preserving and -rejuvenating strategies can help refinement of IOR- and ICR-based synergistic protocols, having value in clinical human rejuvenation.

Transcriptomic analysis of two Beauveria bassiana strains grown on cuticle extracts of the silkworm uncovers their different metabolic response at early infection stage.

Science.gov (United States)

Wang, Jing-Jie; Bai, Wen-Wen; Zhou, Wei; Liu, Jing; Chen, Jie; Liu, Xiao-Yuan; Xiang, Ting-Ting; Liu, Ren-Hua; Wang, Wen-Hui; Zhang, Bao-Ling; Wan, Yong-Ji

2017-05-01

Beauveria bassiana is an important entomopathogenic fungus which not only widely distributes in the environment but also shows phenotypic diversity. However, the mechanism of pathogenic differences among natural B. bassiana strains has not been revealed at transcriptome-wide level. In the present study, in order to explore the mechanism, two B. bassiana strains with different pathogenicity were isolated from silkworms (Bombyx mori L.) and selected to analyze the gene expression of early stage by culturing on cuticle extracts of the silkworm and using RNA-sequencing technique. A total of 2108 up-regulated and 1115 down-regulated genes were identified in B. bassiana strain GXsk1011 (hyper-virulent strain) compared with B. bassiana strain GXtr1009 (hypo-virulent strain), respectively. The function categorization of differential expressed genes (DEGs) showed that most of them involved in metabolic process, biosynthesis of secondary metabolites, catalytic activity, and some involved in nutrition uptake, adhesion and host defense were also noted. Based on our data, distinct pathogenicity among different strains of B. bassiana may largely attribute to unique gene expression pattern which differed at very early infection process. Most of the genes involved in conidia adhesion, cuticle degradation and fungal growth were up-regulated in hyper-virulent B. bassiana strain GXsk1011. Furthermore, in combination with fungal growth analysis, our research provided a clue that fungal growth may also play an important role during early infection process. The results will help to explain why different B. bassiana strains show distinct pathogenicity on the same host even under same condition. Moreover, the transcriptome data were also useful for screening potential virulence factors. Copyright © 2017 Elsevier Inc. All rights reserved.

Cell-penetrating DNA-binding protein as a safe and efficient naked DNA delivery carrier in vitro and in vivo

International Nuclear Information System (INIS)

Kim, Eun-Sung; Yang, Seung-Woo; Hong, Dong-Ki; Kim, Woo-Taek; Kim, Ho-Guen; Lee, Sang-Kyou

2010-01-01

Non-viral gene delivery is a safe and suitable alternative to viral vector-mediated delivery to overcome the immunogenicity and tumorigenesis associated with viral vectors. Using the novel, human-origin Hph-1 protein transduction domain that can facilitate the transduction of protein into cells, we developed a new strategy to deliver naked DNA in vitro and in vivo. The new DNA delivery system contains Hph-1-GAL4 DNA-binding domain (DBD) fusion protein and enhanced green fluorescent protein (EGFP) reporter plasmid that includes the five repeats of GAL4 upstream activating sequence (UAS). Hph-1-GAL4-DBD protein formed complex with plasmid DNA through the specific interaction between GAL4-DBD and UAS, and delivered into the cells via the Hph-1-PTD. The pEGFP DNA was successfully delivered by the Hph-1-GAL4 system, and the EGFP was effectively expressed in mammalian cells such as HeLa and Jurkat, as well as in Bright Yellow-2 (BY-2) plant cells. When 10 μg of pEGFP DNA was intranasally administered to mice using Hph-1-GAL4 protein, a high level of EGFP expression was detected throughout the lung tissue for 7 days. These results suggest that an Hph-1-PTD-mediated DNA delivery strategy may be an useful non-viral DNA delivery system for gene therapy and DNA vaccines.

Cell-penetrating DNA-binding protein as a safe and efficient naked DNA delivery carrier in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Kim, Eun-Sung; Yang, Seung-Woo [Department of Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Hong, Dong-Ki; Kim, Woo-Taek [Department of Biology, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Ho-Guen [Department of Pathology, Yonsei Medical School, Seoul 120-752 (Korea, Republic of); Lee, Sang-Kyou, E-mail: sjrlee@yonsei.ac.kr [Department of Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

2010-01-29

Non-viral gene delivery is a safe and suitable alternative to viral vector-mediated delivery to overcome the immunogenicity and tumorigenesis associated with viral vectors. Using the novel, human-origin Hph-1 protein transduction domain that can facilitate the transduction of protein into cells, we developed a new strategy to deliver naked DNA in vitro and in vivo. The new DNA delivery system contains Hph-1-GAL4 DNA-binding domain (DBD) fusion protein and enhanced green fluorescent protein (EGFP) reporter plasmid that includes the five repeats of GAL4 upstream activating sequence (UAS). Hph-1-GAL4-DBD protein formed complex with plasmid DNA through the specific interaction between GAL4-DBD and UAS, and delivered into the cells via the Hph-1-PTD. The pEGFP DNA was successfully delivered by the Hph-1-GAL4 system, and the EGFP was effectively expressed in mammalian cells such as HeLa and Jurkat, as well as in Bright Yellow-2 (BY-2) plant cells. When 10 {mu}g of pEGFP DNA was intranasally administered to mice using Hph-1-GAL4 protein, a high level of EGFP expression was detected throughout the lung tissue for 7 days. These results suggest that an Hph-1-PTD-mediated DNA delivery strategy may be an useful non-viral DNA delivery system for gene therapy and DNA vaccines.

Human universe

CERN Document Server

Cox, Brian

2014-01-01

Human life is a staggeringly strange thing. On the surface of a ball of rock falling around a nuclear fireball in the blackness of a vacuum the laws of nature conspired to create a naked ape that can look up at the stars and wonder where it came from. What is a human being? Objectively, nothing of consequence. Particles of dust in an infinite arena, present for an instant in eternity. Clumps of atoms in a universe with more galaxies than people. And yet a human being is necessary for the question itself to exist, and the presence of a question in the universe - any question - is the most wonderful thing. Questions require minds, and minds bring meaning. What is meaning? I don't know, except that the universe and every pointless speck inside it means something to me. I am astonished by the existence of a single atom, and find my civilisation to be an outrageous imprint on reality. I don't understand it. Nobody does, but it makes me smile. This book asks questions about our origins, our destiny, and our place i...

Development of a Textile Nanocomposite as Naked Eye Indicator of the Exposition to Strong Acids

Directory of Open Access Journals (Sweden)

Isabel Pallás

2017-09-01

Full Text Available Chemical burns, mainly produced by acids, are a topic of concern. A new sensing material for the detection of strong acids able to be incorporated into textiles has been developed. The material is prepared by the covalent attachment of 2,2′,4,4′,4″-pentamethoxy triphenyl methanol to a mesoporous material which further is included in a nitro resin to obtain a colourless composite. The response of this composite to diverse acid solutions was tested showing the appearance of an intense purple colour (with a colour difference higher than 160 that can be monitored by the naked eye or could be easily digitised to feed an instrumental sensor. Reversibility and resistance to washing cycles were studied with positive results. Finally, the response of the sensing composite to acid vapours was assayed, observing a colour change similar to that found in solution.

Naked Hair Shafts as a Marker of Cicatricial Alopecia.

Science.gov (United States)

Doytcheva, Kristina; Tan, Timothy; Guitart, Joan; Gerami, Pedram; Yazdan, Pedram

2018-07-01

Naked hair shafts (NHS) are free-floating hair shafts devoid of surrounding epithelium, supporting structures, and/or embedded in inflammation that may result from destruction of hair follicles by scarring processes such as inflammation and fibroplasia. Extensive examination of NHS has not been performed in scalp biopsies of alopecia. We retrospectively evaluated 622 scalp biopsies of alopecia [345 cicatricial alopecias (central centrifugal cicatricial alopecia, lichen planopilaris, discoid lupus erythematosus, acne keloidalis nuchae, and folliculitis decalvans] and 277 non-cicatricial alopecias [alopecia areata, androgenic alopecia, telogen effluvium, and psoriatic alopecia)] for the presence of NHS. NHS occurred in 0.72% (2/277) of non-cicatricial alopecias (1/102 of alopecia areata, 1/150 of androgenic alopecia, 0/17 of telogen effluvium, and 0/8 of psoriatic alopecia) and 20% (72/345) of cicatricial alopecias (27/118 of central centrifugal cicatricial alopecia, 29/109 of lichen planopilaris, 2/75 of discoid lupus erythematosus, 11/16 of acne keloidalis nuchae, and 3/27 of folliculitis decalvans). The presence of NHS was significantly increased in cicatricial alopecias in comparison with non-cicatricial alopecias; P value <0.0001. Among the cicatricial alopecias, 26% (92/345) had mild inflammation and/or fibrosis, of which 9% (9/92) had NHS. There were 73% (253/345) that had moderate to severe inflammation and/or fibrosis, of which 24% (63/253) had NHS, indicating that as the severity of inflammation and fibrosis increases, so does the presence of NHS. NHS rarely occurs in non-cicatricial alopecias. This variation may result from destruction of hair follicles by the inflammatory and scarring processes. The presence of NHS may be a useful adjunctive histopathologic feature in the diagnosis of cicatricial alopecia.

An efficient probe for rapid detection of cyanide in water at parts per billion levels and naked-eye detection of endogenous cyanide.

Science.gov (United States)

Kumari, Namita; Jha, Satadru; Bhattacharya, Santanu

2014-03-01

A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the "naked-eye" detection of cyanide ions in water with a visual color change from red to yellow (Δλmax =80 nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for "in-field" experiments without requiring any sophisticated instruments. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Running Shoes with Abrasion Resistant Rubber Sole on the Exercise Capacity of the Human Body

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Bo Wang

2017-10-01

Full Text Available With the development of industrialization, rubber has been gradually used in the manufacture of sports equipment for its favourable properties. This study involved the addition of C5 petroleum resin into brominated isobutylene-isoprene rubber (BIIR and butadiene rubber (BR while manufacturing the sole of running shoes. The effects of running shoes with abrasion resistant rubber sole on the exercise capacity of the human body were investigated by analysing the skid resistance and abrasion resistance of the running shoes, and conducting biomechanical study on naked feet and feet wearing the shoes. The results demonstrated that the rubber sole had favourable slip resistance property and mechanical properties such as stretching, abrasion resistance, and hardness. Compared to naked feet, the peak pressure intensity of the whole step of feet wearing the newly developed shoes, was significantly lower than that of feet wearing ordinary shoes. In the future, rubber can bring more comfortable experience because of its favourable properties.

Human pentastomiasis in Sub-Saharan Africa.

Science.gov (United States)

Vanhecke, C; Le-Gall, P; Le Breton, M; Malvy, D

2016-09-01

Pentastomiasis is a rare zoonotic infection but it is frequently observed in Africa and Asia. Most human infections are caused by members of the Armillifer armillatus species. They are responsible for visceral pentastomiasis in Western and Central Africa. Humans may be infected by eating infected undercooked snake meat or by direct contact with an infected reptile. An increasing number of infections are being reported in Congo, Nigeria, and Cameroon. Despite an occasionally high number of nymphs observed in human viscera, most infections are asymptomatic and often diagnosed by accident during surgery or autopsy. The clinical presentation of pentastomiasis is quite varied and depends on infected tissues. The liver, lungs, and pleura are most frequently involved. Abdominal emergencies have been reported. Diagnostic delays always occur and diagnosis focuses on the patient's lifestyle and living environment. It is mainly based on the morphological description of the parasite's calcified cuticle, the site of the lesion, and the parasite's region of origin. Most patients do not require any treatment. Personal measures such as avoidance of contact with snake droppings are recommended to prevent transmission. Imported pentastomiasis has been observed in African migrants. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Q2122-444: A NAKED ACTIVE GALACTIC NUCLEUS FULLY DRESSED

International Nuclear Information System (INIS)

Gliozzi, M.; Satyapal, S.; Panessa, F.; Franca, F. La; Saviane, I.; Monaco, L.; Foschini, L.; Kedziora-Chudczer, L.; Sambruna, R. M.

2010-01-01

Based on previous spectral and temporal optical studies, Q2122-444 has been classified as a naked active galactic nucleus (AGN) or true type 2 AGN, that is, an AGN that genuinely lacks a broad-line region (BLR). Its optical spectrum seemed to possess only narrow forbidden emission lines that are typical of type 2 (obscured) AGNs, but the long-term optical light curve, obtained from a monitoring campaign over more than two decades, showed strong variability, apparently ruling out the presence of heavy obscuration. Here we present the results from a ∼40 ks XMM-Newton observation of Q2122-444 carried out to shed light on the energetics of this enigmatic AGN. The X-ray analysis was complemented with Australia Telescope Compact Array radio data to assess the possible presence of a jet, and with new NTT/EFOSC2 optical spectroscopic data to verify the actual absence of a BLR. The higher-quality optical data revealed the presence of strong and broad Balmer lines that are at odds with the previous spectral classification of this AGN. The lack of detection of radio emission rules out the presence of a jet. The X-ray data combined with simultaneous UV observations carried out by the Optical Monitor (OM) aboard XMM-Newton confirm that Q2122-444 is a typical type 1 AGN without any significant intrinsic absorption. New estimates of the black hole mass independently obtained from the broad Balmer lines and from a new scaling technique based on X-ray spectral data suggest that Q2122-444 is accreting at a relatively high rate in Eddington units.

Cardiac function of the naked mole-rat: ecophysiological responses to working underground.

Science.gov (United States)

Grimes, Kelly M; Voorhees, Andrew; Chiao, Ying Ann; Han, Hai-Chao; Lindsey, Merry L; Buffenstein, Rochelle

2014-03-01

The naked mole-rat (NMR) is a strictly subterranean rodent with a low resting metabolic rate. Nevertheless, it can greatly increase its metabolic activity to meet the high energetic demands associated with digging through compacted soils in its xeric natural habitat where food is patchily distributed. We hypothesized that the NMR heart would naturally have low basal function and exhibit a large cardiac reserve, thereby mirroring the species' low basal metabolism and large metabolic scope. Echocardiography showed that young (2-4 yr old) healthy NMRs have low fractional shortening (28 ± 2%), ejection fraction (43 ± 2%), and cardiac output (6.5 ± 0.4 ml/min), indicating low basal cardiac function. Histology revealed large NMR cardiomyocyte cross-sectional area (216 ± 10 μm(2)) and cardiac collagen deposition of 2.2 ± 0.4%. Neither of these histomorphometric traits was considered pathological, since biaxial tensile testing showed no increase in passive ventricular stiffness. NMR cardiomyocyte fibers showed a low degree of rotation, contributing to the observed low NMR cardiac contractility. Interestingly, when the exercise mimetic dobutamine (3 μg/g ip) was administered, NMRs showed pronounced increases in fractional shortening, ejection fraction, cardiac output, and stroke volume, indicating an increased cardiac reserve. The relatively low basal cardiac function and enhanced cardiac reserve of NMRs are likely to be ecophysiological adaptations to life in an energetically taxing environment.

Significant Suppression of CT Radiation-Induced DNA Damage in Normal Human Cells by the PrC-210 Radioprotector.

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Jermusek, Frank; Benedict, Chelsea; Dreischmeier, Emma; Brand, Michael; Uder, Michael; Jeffery, Justin J; Ranallo, Frank N; Fahl, William E

2018-05-21

While computed tomography (CT) is now commonly used and considered to be clinically valuable, significant DNA double-strand breaks (γ-H2AX foci) in white blood cells from adult and pediatric CT patients have been frequently reported. In this study to determine whether γ-H2AX foci and X-ray-induced naked DNA damage are suppressed by administration of the PrC-210 radioprotector, human blood samples were irradiated in a CT scanner at 50-150 mGy with or without PrC-210, and γ-H2AX foci were scored. X-ray-induced naked DNA damage was also studied, and the DNA protective efficacy of PrC-210 was compared against 12 other common "antioxidants." PrC-210 reduced CT radiation-induced γ-H2AX foci in white blood cells to near background ( P 95% DNA damage. A systemic PrC-210 dose known to confer 100% survival in irradiated mice had no discernible effect on micro-CT image signal-to-noise ratio and CT image integrity. PrC-210 suppressed DNA damage to background or near background in each of these assay systems, thus supporting its development as a radioprotector for humans in multiple radiation exposure settings.

Naked singularities, branes and Chern-Simons couplings: The dark side of the 2+1 black hole

International Nuclear Information System (INIS)

Zanelli, Jorge

2010-01-01

Branes are naked singularities, analogous to linear or planar defects in crystals. Zero-branes in AdS spacetimes are n egative mass black holes , which can be generalized to higher-dimensional branes. When these solutions are endowed with angular momentum, the extremal spinning branes correspond to BPS states. On the other hand, the 2p-branes, spanning a (2p + 1)-dimensional worldsheet, provide a naturally coupling to CS field theories defined on a D-dimensional spacetime, with D > 2p + 1. In this picture, the field that lives in the D-dimensional spacetime, as well as the sources that couple to it are made out of the same stuff -an SO(D - 1,2) connection. The fact that on the brane the AdS group is necessarily broken down to SO(2p, 2), brings in a number of tensor fields that play the role of charged matter living on the brane.

Proč rypoši nestárnou?

OpenAIRE

Jelínková, Alena

2016-01-01

Naked mole rat and blind mole rat are useful model organisms for human age-associated diaseases studies. Unlike human, their long lifespan is not accompanied by physical health impairment. In both species, the genes involved in aging process or carcinogenesis are under positive selection or their regulation differs from the regulatory pattern known in other rodents or human. Some genes are present in higher number of copies, missing or entirely new and not observed in other organisms. In nake...

Synthesis and characterization of azo-guanidine based alcoholic media naked eye DNA sensor

Science.gov (United States)

Hashmat, Uzma; Yousaf, Muhammad; Lal, Bhajan; Ullah, Shafiq; Holder, Alvin A.; Badshah, Amin

2016-01-01

DNA sensing always has an open meadow of curiosity for biotechnologists and other researchers. Recently, in this field, we have introduced an emerging class of molecules containing azo and guanidine functionalities. In this study, we have synthesized three new compounds (UA1, UA6 and UA7) for potential application in DNA sensing in alcoholic medium. The synthesized materials were characterized by elemental analysis, FTIR, UV-visible, 1H NMR and 13C NMR spectroscopies. Their DNA sensing potential were investigated by UV-visible spectroscopy. The insight of interaction with DNA was further investigated by electrochemical (cyclic voltammetry) and hydrodynamic (viscosity) studies. The results showed that compounds have moderate DNA binding properties, with the binding constants range being 7.2 × 103, 2.4 × 103 and 0.2 × 103 M−1, for UA1, UA6 and UA7, respectively. Upon binding with DNA, there was a change in colour (a blue shift in the λmax value) which was observable with a naked eye. These results indicated the potential of synthesized compounds as DNA sensors with detection limit 1.8, 5.8 and 4.0 ng µl−1 for UA1, UA6 and UA7, respectively. PMID:28018613

Self-similar cosmological solutions with dark energy. II. Black holes, naked singularities, and wormholes

International Nuclear Information System (INIS)

Maeda, Hideki; Harada, Tomohiro; Carr, B. J.

2008-01-01

We use a combination of numerical and analytical methods, exploiting the equations derived in a preceding paper, to classify all spherically symmetric self-similar solutions which are asymptotically Friedmann at large distances and contain a perfect fluid with equation of state p=(γ-1)μ with 0<γ<2/3. The expansion of the Friedmann universe is accelerated in this case. We find a one-parameter family of self-similar solutions representing a black hole embedded in a Friedmann background. This suggests that, in contrast to the positive pressure case, black holes in a universe with dark energy can grow as fast as the Hubble horizon if they are not too large. There are also self-similar solutions which contain a central naked singularity with negative mass and solutions which represent a Friedmann universe connected to either another Friedmann universe or some other cosmological model. The latter are interpreted as self-similar cosmological white hole or wormhole solutions. The throats of these wormholes are defined as two-dimensional spheres with minimal area on a spacelike hypersurface and they are all nontraversable because of the absence of a past null infinity

Initial Case Reports of Cancer in Naked Mole-rats (Heterocephalus glaber).

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Delaney, M A; Ward, J M; Walsh, T F; Chinnadurai, S K; Kerns, K; Kinsel, M J; Treuting, P M

2016-05-01

Naked mole-rats (NMRs;Heterocephalus glaber) are highly adapted, eusocial rodents renowned for their extreme longevity and resistance to cancer. Because cancer has not been formally described in this species, NMRs have been increasingly utilized as an animal model in aging and cancer research. We previously reported the occurrence of several age-related diseases, including putative pre-neoplastic lesions, in zoo-housed NMR colonies. Here, we report for the first time 2 cases of cancer in zoo-housed NMRs. In Case No. 1, we observed a subcutaneous mass in the axillary region of a 22-year-old male NMR, with histologic, immunohistochemical (pancytokeratin positive, rare p63 immunolabeling, and smooth muscle actin negative), and ultrastructural characteristics of an adenocarcinoma possibly of mammary or salivary origin. In Case No. 2, we observed a densely cellular, poorly demarcated gastric mass of polygonal cells arranged in nests with positive immunolabeling for synaptophysin and chromogranin indicative of a neuroendocrine carcinoma in an approximately 20-year-old male NMR. We also include a brief discussion of other proliferative growths and pre-cancerous lesions diagnosed in 1 zoo colony. Although these case reports do not alter the longstanding observation of cancer resistance, they do raise questions about the scope of cancer resistance and the interpretation of biomedical studies in this model. These reports also highlight the benefit of long-term disease investigations in zoo-housed populations to better understand naturally occurring disease processes in species used as models in biomedical research. © The Author(s) 2016.

And the beat goes on: maintained cardiovascular function during aging in the longest-lived rodent, the naked mole-rat.

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Grimes, Kelly M; Reddy, Anilkumar K; Lindsey, Merry L; Buffenstein, Rochelle

2014-08-01

The naked mole-rat (NMR) is the longest-lived rodent known, with a maximum lifespan potential (MLSP) of >31 years. Despite such extreme longevity, these animals display attenuation of many age-associated diseases and functional changes until the last quartile of their MLSP. We questioned if such abilities would extend to cardiovascular function and structure in this species. To test this, we assessed cardiac functional reserve, ventricular morphology, and arterial stiffening in NMRs ranging from 2 to 24 years of age. Dobutamine echocardiography (3 μg/g ip) revealed no age-associated changes in left ventricular (LV) function either at baseline or with exercise-like stress. Baseline and dobutamine-induced LV pressure parameters also did not change. Thus the NMR, unlike other mammals, maintains cardiac reserve with age. NMRs showed no cardiac hypertrophy, evidenced by no increase in cardiomyocyte cross-sectional area or LV dimensions with age. Age-associated arterial stiffening does not occur since there are no changes in aortic blood pressures or pulse-wave velocity. Only LV interstitial collagen deposition increased 2.5-fold from young to old NMRs (P < 0.01). However, its effect on LV diastolic function is likely minor since NMRs experience attenuated age-related increases in diastolic dysfunction in comparison with other species. Overall, these findings conform to the negligible senescence phenotype, as NMRs largely stave off cardiovascular changes for at least 75% of their MLSP. This suggests that using a comparative strategy to find factors that change with age in other mammals but not NMRs could provide novel targets to slow or prevent cardiovascular aging in humans.

Cerebellar Expression of the Neurotrophin Receptor p75 in Naked-Ataxia Mutant Mouse

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Maryam Rahimi Balaei

2016-01-01

Full Text Available Spontaneous mutation in the lysosomal acid phosphatase 2 (Acp2 mouse (nax—naked-ataxia mutant mouse correlates with severe cerebellar defects including ataxia, reduced size and abnormal lobulation as well as Purkinje cell (Pc degeneration. Loss of Pcs in the nax cerebellum is compartmentalized and harmonized to the classic pattern of gene expression of the cerebellum in the wild type mouse. Usually, degeneration starts in the anterior and posterior zones and continues to the central and nodular zones of cerebellum. Studies have suggested that the p75 neurotrophin receptor (NTR plays a role in Pc degeneration; thus, in this study, we investigated the p75NTR pattern and protein expression in the cerebellum of the nax mutant mouse. Despite massive Pc degeneration that was observed in the nax mouse cerebellum, p75NTR pattern expression was similar to the HSP25 pattern in nax mice and comparable with wild type sibling cerebellum. In addition, immunoblot analysis of p75NTR protein expression did not show any significant difference between nax and wild type sibling (p > 0.5. In comparison with wild type counterparts, p75NTR pattern expression is aligned with the fundamental cytoarchitecture organization of the cerebellum and is unchanged in the nax mouse cerebellum despite the severe neurodevelopmental disorder accompanied with Pc degeneration.

Secondary metabolite gene clusters in the entomopathogen fungus Metarhizium anisopliae: genome identification and patterns of expression in a cuticle infection model

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Nicolau Sbaraini

2016-10-01

Full Text Available Abstract Background The described species from the Metarhizium genus are cosmopolitan fungi that infect arthropod hosts. Interestingly, while some species infect a wide range of hosts (host-generalists, other species infect only a few arthropods (host-specialists. This singular evolutionary trait permits unique comparisons to determine how pathogens and virulence determinants emerge. Among the several virulence determinants that have been described, secondary metabolites (SMs are suggested to play essential roles during fungal infection. Despite progress in the study of pathogen-host relationships, the majority of genes related to SM production in Metarhizium spp. are uncharacterized, and little is known about their genomic organization, expression and regulation. To better understand how infection conditions may affect SM production in Metarhizium anisopliae, we have performed a deep survey and description of SM biosynthetic gene clusters (BGCs in M. anisopliae, analyzed RNA-seq data from fungi grown on cattle-tick cuticles, evaluated the differential expression of BGCs, and assessed conservation among the Metarhizium genus. Furthermore, our analysis extended to the construction of a phylogeny for the following three BGCs: a tropolone/citrinin-related compound (MaPKS1, a pseurotin-related compound (MaNRPS-PKS2, and a putative helvolic acid (MaTERP1. Results Among 73 BGCs identified in M. anisopliae, 20 % were up-regulated during initial tick cuticle infection and presumably possess virulence-related roles. These up-regulated BGCs include known clusters, such as destruxin, NG39x and ferricrocin, together with putative helvolic acid and, pseurotin and tropolone/citrinin-related compound clusters as well as uncharacterized clusters. Furthermore, several previously characterized and putative BGCs were silent or down-regulated in initial infection conditions, indicating minor participation over the course of infection. Interestingly, several up

Electrochromic Asymmetric Supercapacitor Windows Enable Direct Determination of Energy Status by the Naked Eye.

Science.gov (United States)

Zhong, Ying; Chai, Zhisheng; Liang, Zhimin; Sun, Peng; Xie, Weiguang; Zhao, Chuanxi; Mai, Wenjie

2017-10-04

Because of the popularity of smart electronics, multifunctional energy storage devices, especially electrochromic supercapacitors (SCs), have attracted tremendous research interest. Herein, a solid-state electrochromic asymmetric SC (ASC) window is designed and fabricated by introducing WO 3 and polyaniline as the negative and positive electrodes, respectively. The two complementary materials contribute to the outstanding electrochemical and electrochromic performances of the fabricated device. With an operating voltage window of 1.4 V and an areal capacitance of 28.3 mF cm -2 , the electrochromic devices show a high energy density of 7.7 × 10 -3 mW h cm -2 . Meanwhile, they exhibit an obvious and reversible color transition between light green (uncharged state) and dark blue (charged state), with an optical transmittance change between 55 and 12% at a wavelength of 633 nm. Hence, the energy storage level of the ASC is directly related to its color and can be determined by the naked eye, which means it can be incorporated with other energy cells to visual display their energy status. Particularly, a self-powered and color-indicated system is achieved by combining the smart windows with commercial solar cell panels. We believe that the novel electrochromic ASC windows will have great potential application for both smart electronics and smart buildings.

Sociality and the telencephalic distribution of corticotrophin-releasing factor, urocortin 3, and binding sites for CRF type 1 and type 2 receptors: A comparative study of eusocial naked mole-rats and solitary Cape mole-rats.

Science.gov (United States)

Coen, Clive W; Kalamatianos, Theodosis; Oosthuizen, Maria K; Poorun, Ravi; Faulkes, Christopher G; Bennett, Nigel C

2015-11-01

Various aspects of social behavior are influenced by the highly conserved corticotrophin-releasing factor (CRF) family of peptides and receptors in the mammalian telencephalon. This study has mapped and compared the telencephalic distribution of the CRF receptors, CRF1 and CRF2 , and two of their ligands, CRF and urocortin 3, respectively, in African mole-rat species with diametrically opposed social behavior. Naked mole-rats live in large eusocial colonies that are characterized by exceptional levels of social cohesion, tolerance, and cooperation in burrowing, foraging, defense, and alloparental care for the offspring of the single reproductive female. Cape mole-rats are solitary; they tolerate conspecifics only fleetingly during the breeding season. The telencephalic sites at which the level of CRF1 binding in naked mole-rats exceeds that in Cape mole-rats include the basolateral amygdaloid nucleus, hippocampal CA3 subfield, and dentate gyrus; in contrast, the level is greater in Cape mole-rats in the shell of the nucleus accumbens and medial habenular nucleus. For CRF2 binding, the sites with a greater level in naked mole-rats include the basolateral amygdaloid nucleus and dentate gyrus, but the septohippocampal nucleus, lateral septal nuclei, amygdalostriatal transition area, bed nucleus of the stria terminalis, and medial habenular nucleus display a greater level in Cape mole-rats. The results are discussed with reference to neuroanatomical and behavioral studies of various species, including monogamous and promiscuous voles. By analogy with findings in those species, we speculate that the abundance of CRF1 binding in the nucleus accumbens of Cape mole-rats reflects their lack of affiliative behavior. © 2015 Wiley Periodicals, Inc.

Qualitative investigation of fresh human scalp hair with full-field optical coherence tomography

Science.gov (United States)

Choi, Woo June; Pi, Long-Quan; Min, Gihyeon; Lee, Won-Soo; Lee, Byeong Ha

2012-03-01

We have investigated depth-resolved cellular structures of unmodified fresh human scalp hairs with ultrahigh-resolution full-field optical coherence tomography (FF-OCT). The Linnik-type white light interference microscope has been home-implemented to observe the micro-internal layers of human hairs in their natural environment. In hair shafts, FF-OCT has qualitatively revealed the cellular hair compartments of cuticle and cortex layers involved in keratin filaments and melanin granules. No significant difference between black and white hair shafts was observed except for absence of only the melanin granules in the white hair, reflecting that the density of the melanin granules directly affects the hair color. Anatomical description of plucked hair bulbs was also obtained with the FF-OCT in three-dimensions. We expect this approach will be useful for evaluating cellular alteration of natural hairs on cosmetic assessment or diagnosis of hair diseases.

Evidence for a new particle with naked ''beauty'' and for its associated production in high-energy (pp) interactions

International Nuclear Information System (INIS)

Basile, M.; Bonvicini, G.; Cara Romeo, G.; Cifarelli, L.; Contin, A.; D'Ali, G.; Di Cesare, P.; Esposito, B.; Giusti, P.; Massam, T.; Nania, R.; Palmonari, F.; Sartorelli, G.; Valenti, G.; Zichichi, A.; Bologna Univ.; Perugia Univ.

1981-01-01

Evidence is reported for the existence, with six standard deviations significance, of a new particle: the heaviest baryon observed so far, whose mass is measured to be m = (5,425 +- 75 175 ) MeV/c 2 . Its width is compatible with zero. It is electrically neutral and it decays into a proton, a D 0 , and a π - . This particle is produced in association with a hadronic state whose semileptonic decay contains a positive electron. The partial cross section for the observed effect is δσ = (3.8 +- 1.2) x 10 - 35 cm 2 . The interpretation of these results is in terms of the associated production of naked ''beauty'' states in (pp) interactions at √s = 62 GeV c.m. energy. The new particle is identified as the first ''beauty''-flavoured baryon with quark composition (udb), i.e. the #betta# 0 sub(b). The discrimination power of the experiment against ''known'' physics, is of the order of 10 - 10 . (author)

The colours of humanity: the evolution of pigmentation in the human lineage.

Science.gov (United States)

Jablonski, Nina G; Chaplin, George

2017-07-05

Humans are a colourful species of primate, with human skin, hair and eye coloration having been influenced by a great variety of evolutionary forces throughout prehistory. Functionally naked skin has been the physical interface between the physical environment and the human body for most of the history of the genus Homo , and hence skin coloration has been under intense natural selection. From an original condition of protective, dark, eumelanin-enriched coloration in early tropical-dwelling Homo and Homo sapiens , loss of melanin pigmentation occurred under natural selection as Homo sapiens dispersed into non-tropical latitudes of Africa and Eurasia. Genes responsible for skin, hair and eye coloration appear to have been affected significantly by population bottlenecks in the course of Homo sapiens dispersals. Because specific skin colour phenotypes can be created by different combinations of skin colour-associated genetic markers, loss of genetic variability due to genetic drift appears to have had negligible effects on the highly redundant genetic 'palette' for the skin colour. This does not appear to have been the case for hair and eye coloration, however, and these traits appear to have been more strongly influenced by genetic drift and, possibly, sexual selection.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).

Renal Pathology in a Nontraditional Aging Model: The Naked Mole-Rat (Heterocephalus glaber).

Science.gov (United States)

Delaney, M A; Kinsel, M J; Treuting, P M

2016-03-01

The naked mole-rat (NMR; Heterocephalus glaber) is growing in popularity as a model for aging research due to its extreme longevity (up to 30 years), highly adapted physiology, and resistance to cancer, particularly when compared with traditional aging models such as laboratory mice and rats. Despite the NMR's seemingly lengthy health span, several age-related lesions have been documented. During a 15-year retrospective evaluation of a zoo-housed population, histologic changes in the kidneys were reported in 127 of 138 (92%) adult NMRs. Of these, renal tubular mineralization was very common (115 of 127; 90.6%) and found in NMRs without concurrent renal lesions (36 of 127; 28.3%). Many of the other described lesions were considered progressive stages of a single process, generally referred to as chronic nephritis or nephropathy, and diagnosed in 73 of 127 (57.5%), while end-stage renal disease was reported in only 12 (9.4%) NMRs. Renal lesions of these NMRs were comparable to disease entities reported in laboratory rats and certain strains of inbred and noninbred mice. Although many lesions of NMR kidneys were similar to those found in aged laboratory rodents, some common urinary diseases were not represented in the examined colonies. The goal of this study was to describe renal lesions in NMRs from a zoologic setting to familiarize investigators and pathologists with an apparently common and presumably age-related disease in this nontraditional model. © The Author(s) 2015.

CONSTRAINTS ON THE EMISSION MODEL OF THE 'NAKED-EYE BURST' GRB 080319B

International Nuclear Information System (INIS)

Abdo, A. A.; Abeysekara, A. U.; Linnemann, J. T.; Allen, B. T.; Chen, C.; Aune, T.; Berley, D.; Goodman, J. A.; Christopher, G. E.; Kolterman, B. E.; Mincer, A. I.; DeYoung, T.; Dingus, B. L.; Hoffman, C. M.; Ellsworth, R. W.; Gonzalez, M. M.; Granot, J.; Hays, E.; McEnery, J. E.; Hüntemeyer, P. H.

2012-01-01

On 2008 March 19, one of the brightest gamma-ray bursts (GRBs) ever recorded was detected by several ground- and space-based instruments spanning the electromagnetic spectrum from radio to gamma rays. With a peak visual magnitude of 5.3, GRB 080319B was dubbed the 'naked-eye' GRB, as an observer under dark skies could have seen the burst without the aid of an instrument. Presented here are results from observations of the prompt phase of GRB 080319B taken with the Milagro TeV observatory. The burst was observed at an elevation angle of 47°. Analysis of the data is performed using both the standard air shower method and the scaler or single-particle technique, which results in a sensitive energy range that extends from ∼5 GeV to >20 TeV. These observations provide the only direct constraints on the properties of the high-energy gamma-ray emission from GRB 080319B at these energies. No evidence for emission is found in the Milagro data, and upper limits on the gamma-ray flux above 10 GeV are derived. The limits on emission between ∼25 and 200 GeV are incompatible with the synchrotron self-Compton model of gamma-ray production and disfavor a corresponding range (2 eV-16 eV) of assumed synchrotron peak energies. This indicates that the optical photons and soft (∼650 keV) gamma rays may not be produced by the same electron population.

Matrix metalloproteinase sensing via porous silicon microcavity devices functionalized with human antibodies

Energy Technology Data Exchange (ETDEWEB)

Martin, Marta; Gergely, Csilla [GES-UMR 5650, CNRS, Universite Montpellier 2, Pl. Eugene Bataillon 34095, Montpellier Cedex 5 (France); Taleb Bendiab, Chakib; Massif, Laurent; Cuisinier, Frederic [EA4203, Faculte d' Odontologie, Universite Montpellier 1, Montpellier Cedex 5 (France); Palestino, Gabriela [Facultad de Ciencias Quimicas, Universidad Autonoma de San Luis Potosi, Av. Salvador Nava 6, 78000 San Luis Potosi (Mexico); Agarwal, Vivechana [CIICAP, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Col Chamilpa, Cuernavaca, Mor. (Mexico)

2011-06-15

Porous silicon microcavity (PSiMc) structures were used as support material for specific sensing of matrix metalloproteinases (MMPs). For lower concentrations of MMP-8, the structures were tested with two types of functionalization methods. Silanization of the oxidized porous silicon structures, followed by glutaraldehyde chemistry was found to give very inconsistent results. The use of biotinilated bovine serum albumin linked to the naked PSiMc was found to be an alternative method to attach the anti MMP-8 human antibody, previously modified with streptavidin, which was further used to sense MMP-8 (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

In vivo expression of ß-galactosidase by rat oviduct exposed to naked DNA or messenger RNA

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MARIANA RIOS

2002-01-01

Full Text Available Intra-oviductal administration of RNA obtained from oviducts of estradiol-treated rats resulted in accelerated egg transport (Ríos et al., 1997. It is probable that estradiol-induced messenger RNA (mRNA entered oviductal cells and was translated into the proteins involved in accelerated egg transport. In order to test this interpretation we deposited in vivo 50 µg of pure ß-galactosidase (ß-gal mRNA, 50 µg of pure DNA from the reporter gene ß-gal under SV40 promoter or the vehicle (control oviducts into the oviductal lumen of rats. Twenty four hours later the ß-gal activity was assayed in oviductal tissue homogenates using o-nitrophenyl-ß-D-galactopyranoside as a substrate. The administration of ß-gal mRNA and pSVBgal plasmid increased ß-gal activity by 71% and 142%, respectively, over the control oviducts. These results indicate that naked DNA and mRNA coding for ß-gal can enter oviductal cells and be translated into an active enzyme. They are consistent with the interpretation that embryo transport acceleration caused by the injection of estradiol-induced RNA in the oviduct involves translation of the injected mRNA

Employing a hydrazine linked asymmetric double naphthalene hybrid for efficient naked eye detection of F-: Crystal structure with real application for F-

Science.gov (United States)

Bhattacharyya, Arghyadeep; Makhal, Subhash Chandra; Ghosh, Soumen; Guchhait, Nikhil

2018-06-01

An asymmetric hydrazide, (12E, 13E)-2-((naphthalen-1-yl) methylene)-1-(1-(2-hydroxynaphthalen-6-yl) ethylidene) hydrazine (abbreviated as AH) is synthesized and characterized by standard techniques and crystal structure of AH has been obtained. The naked eye detection of F- in aqueous acetonitrile (acetonitrile: water = 7:3/v:v) by AH has been investigated by UV-Visible titration and in presence of other anions, the limit of detection being 1.31 × 10-6(M). The mechanism of F- sensing has been explored by 1H NMR titration. AH undergoes hydrogen bonding with F- followed by deprotonation. The practical utility of AH has been explored by successful test kit response and color change in toothpaste solution.

Gene expression in the muscle and central nervous system following intramuscular inoculation of encapsidated or naked poliovirus replicons

International Nuclear Information System (INIS)

Jackson, Cheryl A.; Messinger, Jeff; Palmer, Matthew T.; Peduzzi, Jean D.; Morrow, Casey D.

2003-01-01

The spread of intramuscularly inoculated poliovirus to the central nervous system (CNS) has been documented in humans, monkeys, and mice transgenic for the human poliovirus receptor. Poliovirus spread is thought to be due to infection of the peripheral nerve and retrograde transport of poliovirus through the axon to the neuron cell body, where final virus uncoating occurs and translation/replication ensues. In previous studies, we have shown that polio-based vectors (replicons) can be used for gene delivery to motor neurons of the CNS. Using a replicon that encodes green fluorescent protein (GFP), we found that following intrathecal inoculation, GFP expression was confined to motorneurons of the spinal cord. To further characterize the gene expression of poliovirus in the periphery and CNS, we have intramuscularly inoculated transgenic mice with poliovirus replicons encoding GFP. Expression of GFP was demonstrated in the muscle, sciatic nerve, dorsal root ganglion, and the ventral horn motorneurons following intramuscular inoculation. There was no evidence of paralysis or behavioral abnormalities in the mice following intramuscular inoculation of the replicon encoding GFP. Injection of replicon RNA alone (naked RNA) into the muscle of transgenic mice or rats, which do not express the poliovirus receptor, also resulted in expression of GFP in the muscle, sciatic nerve, dorsal root ganglion, and ventral horn motorneurons, indicating that transport of the replicon RNA from the periphery to CNS had occurred. GFP expression was found in the muscles and sciatic nerve as early as 6 h after injection of replicons or replicon RNA, even after sciatic nerve section. Analysis at longer times postinjection revealed GFP expression similar to 6 h levels in the cut sciatic nerves and robust expression in the nerves of uncut animals. The infection and expression of GFP in the CNS following intramuscular inoculation of encapsidated replicons encoding GFP occurred in juvenile or

Effect of egg washing and correlation between cuticle and egg penetration by various Salmonella strains.

Science.gov (United States)

Gole, Vaibhav C; Roberts, Juliet R; Sexton, Margaret; May, Damian; Kiermeier, Andreas; Chousalkar, Kapil K

2014-07-16

In Australia, Europe and the United States, eggs and egg products are frequently associated with Salmonella food poisoning outbreaks. Many of the egg-associated Salmonella outbreaks have been due to the products such as mayonnaise, ice-cream and cold desserts which are eaten without cooking following the addition of raw egg. The ability of four Salmonella isolates (one each of S. Singapore, S. Adelaide, S. Worthington and S. Livingstone) to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods was investigated in the current study. The results of the agar penetration experiment indicated that all the isolates used in the present study have the capacity to penetrate the eggshell. Eggshell penetration by the S. Worthington isolate was higher but not significant (p=0.06) in washed eggs compared to unwashed eggs. However, for all other isolates (S. Singapore, S. Adelaide and S. Livingstone), there was no significant difference in penetration of washed and unwashed eggs. Statistical analysis indicated that cuticle score was a significant linear predictor of Salmonella eggshell penetration. Whole egg penetration results showed that all of the Salmonella isolates used in the present study were capable of surviving on the eggshell surface after 21days of incubation (at 20°C) following a high dose of inoculation (10(5)CFU/mL). The combined data of all isolates demonstrated that, the survival rate of Salmonella on eggshells (inoculated with 10(5)CFU/mL) was significantly higher (p=0.002) at 20°C as compared to 37°C. S. Singapore, S. Worthington, and S. Livingstone were not detected in egg internal contents whereas S. Adelaide was detected in one egg's internal contents. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Peripheral administration of oxytocin increases social affiliation in the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Mooney, Skyler J; Douglas, Natasha R; Holmes, Melissa M

2014-04-01

The neuropeptide oxytocin regulates a wide variety of social behaviors across diverse species. However, the types of behaviors that are influenced by this hormone are constrained by the species in question and the social organization that a particular species exhibits. Therefore, the present experiments investigated behaviors regulated by oxytocin in a eusocial mammalian species by using the naked mole-rat (Heterocephalus glaber). In Experiment 1, adult non-breeding mole-rats were given intraperitoneal injections of either oxytocin (1mg/kg or 10mg/kg) or saline on alternate days. Animals were then returned to their colony and behavior was recorded for minutes 15-30 post-injection. Both doses of oxytocin increased huddling behavior during this time period. In Experiment 2, animals received intraperitoneal injections of either oxytocin (1mg/kg), an oxytocin-receptor antagonist (0.1mg/kg), a cocktail of oxytocin and the antagonist, or saline across 4 testing days in a counterbalanced design. Animals were placed in either a 2-chamber arena with a familiar conspecific or in a small chamber with 1week old pups from their home colony and behaviors were recorded for minutes 15-30 post-injection. Oxytocin increased investigation of, and time spent in close proximity to, a familiar conspecific; these effects were blocked by the oxytocin antagonist. No effects were seen on pup-directed behavior. These data suggest that oxytocin is capable of modulating affiliative-like behavior in this eusocial species. Copyright © 2014 Elsevier Inc. All rights reserved.

Atmospheric Carbon Dioxide and its Relation to Carbon Cycle Perturbations During Ocean Anoxic Event 1d: A High Resolution Record From Dispersed Plant Cuticle

Science.gov (United States)

Richey, J. D.; Upchurch, G. R.; Joeckel, R.; Smith, J. J.; Ludvigson, G. A.; Lomax, B. H.

2013-12-01

Past geological greenhouse intervals are associated with Ocean Anoxic Events (OAEs), which result from an increase in marine primary productivity and/or an increase in the preservation of organic matter. The end point is widespread black shale deposition combined with a long-term atmospheric positive δ13C excursion and an increase in the burial of 12C. Some OAEs show a negative δ13C excursion preceding the positive excursion, indicating a perturbation in the global carbon cycle prior to the initiation of these events. The Rose Creek (RCP) locality, southeastern Nebraska, is the only known terrestrial section that preserves OAE1d (Cretaceous, Albian-Cenomanian Boundary) and has abundant charcoal and plant cuticle. These features allow for a combined carbon isotope and stomatal index (SI) analysis to determine both changes in the cycling between carbon pools (C isotope analysis) and changes in paleo-CO2 via changes in SI. Preliminary (and ongoing) SI data analysis using dispersed cuticle of Pandemophyllum kvacekii (an extinct Laurel) collected at 30 cm intervals indicate changes in SI consistent with changes in CO2. Fitting our samples to a published RCP δ13C profile, pre-excursion CO2 concentrations are high. CO2 decreases to lower concentrations in the basal 1.2 m of the RCP section, where δ13Cbulk shows a negative excursion and δ13Ccharcoal remains at pre-excursion values. CO2 concentrations become higher toward the top of the negative δ13C excursion, where δ13Cbulk and δ13Ccharcoal are at their most negative values, and drop as the negative carbon excursion terminates. Using published transfer functions, we estimate that pre-excursion CO2 concentrations were a maximum of 900 ppm. In the basal 1.2 m of RCP, CO2 drops to a maximum of 480 ppm, and rises to a maximum of 710 ppm near the top of the negative excursion. As δ13C values rise towards pre-excursion values, CO2 declines to a maximum of 400 ppm. The trend in SI is comparable to the trend in δ13

Yield reduction caused by a soil-borne disease of naked, dwarf, and conventional oat in Finland

Directory of Open Access Journals (Sweden)

P. PELTONEN-SAINIO

2008-12-01

Full Text Available A severe disease occurred in the field plots of naked (cv. Salomon, dwarf (cv. Pal, and conventional oat (cvs. Jalostettu maatiainen and Salo at the Viikki Experimental Farm of the University of Helsinki, Finland, in 1994 and 1995. Symptoms were expressed as grayish-brown necrotic areas on the lower leaves which killed plants from the seedling to heading stage, the effect being cultivar dependent. The proportion of plants killed plants from the seedling to heading stage, the effect being cultivar dependent. The proportion of plants killed contributed to the yield losses. The infection also resulted in less grains per panicle and lower weight of both panicle and vegetative above-ground biomass. From a total of 57 fungal isolates obtained from infected leaves, Fusarium culmorum (W.G.Sm. Sacc. and F. sambucinum Fuck. Dominated and subsequently caused infection (particularly foot and root rot in oat in laboratory tests. These two Fusarium spp. Were considered to be the primary causal agents of the symptoms observed in the field, although other pathogens may have been present. The disease was probably soil-borne. The results of this study suggested that the unusually dry and warm weather during late June and in July was the principal factor behind the severe disease outbreak. ;

A rapid, naked-eye detection of hypochlorite and bisulfite using a robust and highly-photostable indicator dye Quinaldine Red in aqueous medium

Science.gov (United States)

Dutta, Tanoy; Chandra, Falguni; Koner, Apurba L.

2018-02-01

A ;naked-eye; detection of health hazardous bisulfite (HSO3-) and hypochlorite (ClO-) using an indicator dye (Quinaldine Red, QR) in a wide range of pH is demonstrated. The molecule contains a quinoline moiety linked to an N,N-dimethylaniline moiety with a conjugated double bond. Treatment of QR with HSO3- and ClO-, in aqueous solution at near-neutral pH, resulted in a colorless product with high selectivity and sensitivity. The detection limit was 47.8 μM and 0.2 μM for HSO3- and ClO- respectively. However, ClO- was 50 times more sensitive and with 2 times faster response compared to HSO3-. The detail characterization and related analysis demonstrate the potential of QR for a rapid, robust and highly efficient colorimetric sensor for the practical applications to detect hypochlorite in water samples.

A dual-responsive colorimetric and fluorescent chemosensor based on diketopyrrolopyrrole derivative for naked-eye detection of Fe3 + and its practical application

Science.gov (United States)

Zhang, Shanshan; Sun, Tao; Xiao, Dejun; Yuan, Fang; Li, Tianduo; Wang, Enhua; Liu, Haixia; Niu, Qingfen

2018-01-01

A novel dual-responsive colorimetric and fluorescent chemosensor L based on diketopyrrolopyrrole derivative for Fe3 + detection was designed and synthesized. In presence of Fe3 +, sensor L displayed strong colorimetric response as amaranth to rose pink and significant fluorescence enhancement and chromogenic change, which served as a naked-eye indicator by an obvious color change from purple to red. The binding constant for L-Fe3 + complex was found as 2.4 × 104 with the lower detection limit of 14.3 nM. The sensing mechanism was investigated in detail by fluorescence measurements, IR and 1H NMR spectra. Sensor L for Fe3 + detection also exhibited high anti-interference performance, good reversibility, wide pH response range and instantaneous response time. Furthermore, the sensor L has been used to quantify Fe3 + ions in practical water samples with good recovery.

Two dimensional microcirculation mapping with real time spatial frequency domain imaging

Science.gov (United States)

Zheng, Yang; Chen, Xinlin; Lin, Weihao; Cao, Zili; Zhu, Xiuwei; Zeng, Bixin; Xu, M.

2018-02-01

We present a spatial frequency domain imaging (SFDI) study of local hemodynamics in the human finger cuticle of healthy volunteers performing paced breathing and the forearm of healthy young adults performing normal breathing with our recently developed Real Time Single Snapshot Multiple Frequency Demodulation - Spatial Frequency Domain Imaging (SSMD-SFDI) system. A two-layer model was used to map the concentrations of deoxy-, oxy-hemoglobin, melanin, epidermal thickness and scattering properties at the subsurface of the forearm and the finger cuticle. The oscillations of the concentrations of deoxy- and oxy-hemoglobin at the subsurface of the finger cuticle and forearm induced by paced breathing and normal breathing, respectively, were found to be close to out-of-phase, attributed to the dominance of the blood flow modulation by paced breathing or heartbeat. Our results suggest that the real time SFDI platform may serve as one effective imaging modality for microcirculation monitoring.

Recombinant human endostatin reduces hypertrophic scar ...

African Journals Online (AJOL)

Methods: Sixteen New Zealand white rabbits were used to establish HS models. Then, rabbit ears containing HS were randomly assigned to either the Endostar group or the control group. The changes of appearance and histology were evaluated using the naked eye, hematoxylin eosin staining, and a scar elevation index.

Effect of Photon Radiations in Semi-Rigid Artificial Tissue Sensitized by Protoporphyrin IX Encapsulated with Silica Nanoparticles

Science.gov (United States)

Makhadmeh, Ghaseb N.; Aziz, Azlan Abdul; Razak, Khairunisak Abdul; Al-Akhras, M.-Ali H.

2018-02-01

This study involves the synthesis of Protoporphyrin IX (PpIX) encapsulated with Silica Nanoparticles (SiNPs) as an application for Photodynamic therapy. Semi-rigid artificial tissues with optical features similar to human tissue were used as sample materials to ascertain the efficacy of PpIX encapsulated with SiNPs. The disparity in optical characteristics (transmittance, reflectance, scattering, and absorption) of tissues treated with encapsulated PpIX and naked PpIX under light exposure (Intensity at 408 nm ~1.19 mW/cm2) was explored. The optimal exposure times required for naked PpIX and SiNPs encapsulated PpIX to engulf Red Blood Cells (RBCs) in the artificial tissue were subsequently measured. Comparative analysis showed that the encapsulated PpIX has a 91.5 % higher efficacy than naked PpIX. The results prove the applicability of PpIX encapsulated with SiNP on artificial tissue and possible use on human tissue.

Walking the oxidative stress tightrope: a perspective from the naked mole-rat, the longest-living rodent.

Science.gov (United States)

Rodriguez, Karl A; Wywial, Ewa; Perez, Viviana I; Lambert, Adriant J; Edrey, Yael H; Lewis, Kaitlyn N; Grimes, Kelly; Lindsey, Merry L; Brand, Martin D; Buffenstein, Rochelle

2011-01-01

Reactive oxygen species (ROS), by-products of aerobic metabolism, cause oxidative damage to cells and tissue and not surprisingly many theories have arisen to link ROS-induced oxidative stress to aging and health. While studies clearly link ROS to a plethora of divergent diseases, their role in aging is still debatable. Genetic knock-down manipulations of antioxidants alter the levels of accrued oxidative damage, however, the resultant effect of increased oxidative stress on lifespan are equivocal. Similarly the impact of elevating antioxidant levels through transgenic manipulations yield inconsistent effects on longevity. Furthermore, comparative data from a wide range of endotherms with disparate longevity remain inconclusive. Many long-living species such as birds, bats and mole-rats exhibit high-levels of oxidative damage, evident already at young ages. Clearly, neither the amount of ROS per se nor the sensitivity in neutralizing ROS are as important as whether or not the accrued oxidative stress leads to oxidative-damage-linked age-associated diseases. In this review we examine the literature on ROS, its relation to disease and the lessons gleaned from a comparative approach based upon species with widely divergent responses. We specifically focus on the longest lived rodent, the naked mole-rat, which maintains good health and provides novel insights into the paradox of maintaining both an extended healthspan and lifespan despite high oxidative stress from a young age.

Basic Instinct Undressed: Early Spatiotemporal Processing for Primary Sexual Characteristics

Science.gov (United States)

Legrand, Lore B.; Del Zotto, Marzia; Tyrand, Rémi; Pegna, Alan J.

2013-01-01

This study investigates the spatiotemporal dynamics associated with conscious and non-conscious processing of naked and dressed human bodies. To this effect, stimuli of naked men and women with visible primary sexual characteristics, as well as dressed bodies, were presented to 20 heterosexual male and female participants while acquiring high resolution EEG data. The stimuli were either consciously detectable (supraliminal presentations) or were rendered non-conscious through backward masking (subliminal presentations). The N1 event-related potential component was significantly enhanced in participants when they viewed naked compared to dressed bodies under supraliminal viewing conditions. More importantly, naked bodies of the opposite sex produced a significantly greater N1 component compared to dressed bodies during subliminal presentations, when participants were not aware of the stimulus presented. A source localization algorithm computed on the N1 showed that the response for naked bodies in the supraliminal viewing condition was stronger in body processing areas, primary visual areas and additional structures related to emotion processing. By contrast, in the subliminal viewing condition, only visual and body processing areas were found to be activated. These results suggest that naked bodies and primary sexual characteristics are processed early in time (i.e., sexual features benefit from automatic and rapid processing, most likely due to their high relevance for the individual and their importance for the species in terms of reproductive success. PMID:23894532

Strand displacement amplification for ultrasensitive detection of human pluripotent stem cells.

Science.gov (United States)

Wu, Wei; Mao, Yiping; Zhao, Shiming; Lu, Xuewen; Liang, Xingguo; Zeng, Lingwen

2015-06-30

Human pluripotent stem cells (hPSCs), such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), provide a powerful model system for studies of cellular identity and early mammalian development, which hold great promise for regenerative medicine. It is necessary to develop a convenient method to discriminate hPSCs from other cells in clinics and basic research. Herein, a simple and reliable biosensor for stem cell detection was established. In this biosensor system, stage-specific embryonic antigen-3 (SSEA-3) and stage-specific embryonic antigen-4 (SSEA-4) were used to mark human pluripotent stem cells (hPSCs). Antibody specific for SSEA-3 was coated onto magnetic beads for hPSCs enrichment, and antibody specific for SSEA-4 was conjugated with carboxyl-modified tDNA sequence which was used as template for strand displacement amplification (SDA). The amplified single strand DNA (ssDNA) was detected with a lateral flow biosensor (LFB). This biosensor is capable of detecting a minimum of 19 human embryonic stem cells by a strip reader and 100 human embryonic stem cells by the naked eye within 80min. This approach has also shown excellent specificity to distinguish hPSCs from other types of cells, showing that it is promising for specific and handy detection of human pluripotent stem cells. Copyright © 2015 Elsevier B.V. All rights reserved.

ESTIMATION OF THE DEVELOPMENT STANDARD OF NEURAL TUBE IN EMBRYOS FROM TRANSYLVANIAN NAKED NECK AND PLYMOUTH ROCK HEN BREEDS, DURING EARLY EMBRYOGENESIS

Directory of Open Access Journals (Sweden)

D. DRONCA

2007-05-01

Full Text Available In Romania, the Transylvanian Naked Neck hen breed is considered to be an“endangered” population, reason for which we consider that a special attentionshould have been given until now. Plymouth Rock breed was imported for the firsttime to Romania from the Studler Company, France in 1969. This paper is aimingto perform a profound analysis of the development patterns of the neural tube inthe two breeds, by measurements carried out at 30, 40, 50, and 60 hours ofincubation. Observations show that the closure of the neural canal and itstransformation into a tube follows an undulatory pattern, of which positive andnegative curls are diametrically opposed in the two breeds, while the developmentspeed during the whole studied period have a relative similar value between thetwo breeds. We estimate that the two breeds have a good combinative capacity,which recommend the utilization of these genetic materials to obtain hybrids forproducing “peasant-type” chicken meat, very well-appreciated by the Europeansbetween the two World Wars.

Reaching Out to Send a Message: Proteins Associated with Neurite Outgrowth and Neurotransmission are Altered with Age in the Long-Lived Naked Mole-Rat.

Science.gov (United States)

Triplett, Judy C; Swomley, Aaron M; Kirk, Jessime; Grimes, Kelly M; Lewis, Kaitilyn N; Orr, Miranda E; Rodriguez, Karl A; Cai, Jian; Klein, Jon B; Buffenstein, Rochelle; Butterfield, D Allan

2016-07-01

Aging is the greatest risk factor for developing neurodegenerative diseases, which are associated with diminished neurotransmission as well as neuronal structure and function. However, several traits seemingly evolved to avert or delay age-related deterioration in the brain of the longest-lived rodent, the naked mole-rat (NMR). The NMR remarkably also exhibits negligible senescence, maintaining an extended healthspan for ~75 % of its life span. Using a proteomic approach, statistically significant changes with age in expression and/or phosphorylation levels of proteins associated with neurite outgrowth and neurotransmission were identified in the brain of the NMR and include: cofilin-1; collapsin response mediator protein 2; actin depolymerizing factor; spectrin alpha chain; septin-7; syntaxin-binding protein 1; synapsin-2 isoform IIB; and dynamin 1. We hypothesize that such changes may contribute to the extended lifespan and healthspan of the NMR.

Performance comparison of dwarf laying hens segregating for the naked neck gene in temperate and subtropical environments

Directory of Open Access Journals (Sweden)

Bordas André

2009-01-01

Full Text Available Abstract This study compares laying performances between two environments of dwarf laying hen lines segregating for the naked neck mutation (NA locus, a selected dwarf line of brown-egg layers and its control line. Layers with one of the three genotypes at the NA locus were produced from 11 sires from the control line and 12 sires from the selected line. Two hatches produced 216 adult hens in Taiwan and 297 hens in France. Genetic parameters for laying traits were estimated in each environment and the ranking of sire breeding values was compared between environments. Laying performance was lower, and mortality was higher in Taiwan than in France. The line by environment interaction was highly significant for body weight at 16 weeks, clutch length and egg number, with or without Box-Cox transformation. The selected line was more sensitive to environmental change but in Taiwan it could maintain a higher egg number than the control line. Estimated heritability values in the selected line were higher in France than in Taiwan, but not for all the traits in the control line. The rank correlations between sire breeding values were low within the selected line and slightly higher in the control line. A few sire families showed a good ranking in both environments, suggesting that some families may adapt better to environmental change.

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Indian Academy of Sciences (India)

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the most productive marine waters are quite cold. In this and the next essay, ... low temperatures might well compound the problems of .... cuticle of some iridescent red algae (from micrographs of .... transfer in nature and in human technology.

A naked-eye colorimetric "PCR developer"

Science.gov (United States)

Valentini, Paola; Pompa, Pier Paolo

2016-04-01

Despite several advances in molecular biology and diagnostics, Polymerase Chain Reaction (PCR) is currently the gold standard for nucleic acids amplification and detection, due to its versatility, low-cost and universality, with estimated genetically modified organisms, and pathogens). The PCR developer proved to be highly specific and ultra-sensitive, discriminating down to few copies of HIV viral DNA, diluted in an excess of interfering human genomic DNA, which is a clinically relevant viral load. Hence, it could be a valuable tool for both academic research and clinical applications.

Human fatality due to thallium poisoning: autopsy, microscopy, and mass spectrometry assays.

Science.gov (United States)

Li, Shangxun; Huang, Wen; Duan, Yijie; Xing, Jingjun; Zhou, Yiwu

2015-01-01

Thallium has been responsible for many intoxications since its discovery; however, toxicological profiles for thallium in human fatalities have not been updated recently. Autopsy, microscopic investigations, and toxicological analyses were performed on a married couple who died from thallium sulfate intended homicidal poisoning. The distribution of thallium was established by inductively coupled plasma mass spectrometry with hair samples showing the highest thallium concentration. Electron microscopy revealed a dystrophic condition of hair with disorganized cuticle and atrophy of the hair bulb. Thallium interacts with cells at different levels, with prominent ultrastructural injuries in the mitochondria and endoplasmic reticulum, and high concentration of electron dense granules observed in the cytoplasm and mitochondria of several organs. Alopecia, toxic encephalopathy, and peripheral neuropathy were diagnosed in the victims and suggested to be crucial implications for thallium poisoning. The analytical procedures used in this case are of considerable forensic importance in the diagnosis of thallium poisoning. © 2014 American Academy of Forensic Sciences.

Hepatitis B virus evasion from cGAS sensing in human hepatocytes.

Science.gov (United States)

Verrier, Eloi R; Yim, Seung-Ae; Heydmann, Laura; El Saghire, Houssein; Bach, Charlotte; Turon-Lagot, Vincent; Mailly, Laurent; Durand, Sarah C; Lucifora, Julie; Durantel, David; Pessaux, Patrick; Manel, Nicolas; Hirsch, Ivan; Zeisel, Mirjam B; Pochet, Nathalie; Schuster, Catherine; Baumert, Thomas F

2018-04-20

Chronic hepatitis B virus (HBV) infection is a major cause of chronic liver disease and cancer worldwide. The mechanisms of viral genome sensing and the evasion of innate immune responses by HBV infection are still poorly understood. Recently, the cyclic GMP-AMP synthase (cGAS) was identified as a DNA sensor. In this study, we aimed to investigate the functional role of cGAS in sensing of HBV infection and elucidate the mechanisms of viral evasion. We performed functional studies including loss- and gain-of-function experiments combined with cGAS effector gene expression profiling in an infectious cell culture model, primary human hepatocytes and HBV-infected human liver chimeric mice. Here we show that cGAS is expressed in the human liver, primary human hepatocytes and human liver chimeric mice. While naked relaxed-circular HBV DNA is sensed in a cGAS-dependent manner in hepatoma cell lines and primary human hepatocytes, host cell recognition of viral nucleic acids is abolished during HBV infection, suggesting escape from sensing, likely during packaging of the genome into the viral capsid. While the hepatocyte cGAS pathway is functionally active, as shown by reduction of viral cccDNA levels in gain-of-function studies, HBV infection suppressed cGAS expression and function in cell culture models and humanized mice. HBV exploits multiple strategies to evade sensing and antiviral activity of cGAS and its effector pathways. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

A phenolic acid based colourimetric 'naked-eye' chemosensor for the rapid detection of Cu(II) ions

Science.gov (United States)

Sengupta, Priti; Ganguly, Aniruddha; Bose, Adity

2018-06-01

The crucial role of chemosensor for the immediate recognition of environment pollutant motivates the researchers to develop variety of sensing protocols. Of various chemosensory protocols, the colour change observed by the naked eye is considered to be a conceivable and on-site way to indicate the presence of an analyte. We herein report a colourimetric and commercially available absorption probe, sinapic acid (SA) that is completely ready to use for "on-site" visual determination of copper ions. The molecule, SA is well-known phenolic acid, often utilized for its antibacterial activity. In this work, for the first time, we are exploring its ability to work as an efficient Cu2+ sensor. This sensor molecule selectively detected Cu2+ ions by changing its colour from colourless to pink within detection limit of 64.5 nM, which is much lower than other reported sensor molecules and the suggested limit by World Health Organization (WHO) and U. S. Environmental Protection Agency (EPA) guidelines. The sensing mechanism was investigated through UV-vis and 1H NMR titration along with ESI-MS spectroscopy and further confirmed by DFT computational studies. Studies revealed the participation of hydroxyl group (sbnd OH) and methoxy group (sbnd OMe) of SA in complexation with Cu2+. The binding stoichiometry of SA to Cu2+ was found to be 1:2 through Job's plot and ESI-MS analysis. Importantly, paper strips of SA were prepared which could be used for a rapid "on-site" determination of Cu2+ containing samples.

Covalent Binding of Antibodies to Cellulose Paper Discs and Their Applications in Naked-eye Colorimetric Immunoassays.

Science.gov (United States)

Peng, Yanfen; Gelder, Victor Van; Amaladoss, Anburaj; Patel, Kadamb Haribhai

2016-10-21

This report presents two methods for the covalent immobilization of capture antibodies on cellulose filter paper grade No. 1 (medium-flow filter paper) discs and grade No. 113 (fast-flow filter paper) discs. These cellulose paper discs were grafted with amine functional groups through a silane coupling technique before the antibodies were immobilized on them. Periodate oxidation and glutaraldehyde cross-linking methods were used to graft capture antibodies on the cellulose paper discs. In order to ensure the maximum binding capacity of the capture antibodies to their targets after immobilization, the effects of various concentrations of sodium periodate, glutaraldehyde, and capture antibodies on the surface of the paper discs were investigated. The antibodies that were coated on the amine-functionalized cellulose paper discs through a glutaraldehyde cross-linking agent showed enhanced binding activity to the target when compared to the periodate oxidation method. IgG (in mouse reference serum) was used as a reference target in this study to test the application of covalently immobilized antibodies through glutaraldehyde. A new paper-based, enzyme-linked immunosorbent assay (ELISA) was successfully developed and validated for the detection of IgG. This method does not require equipment, and it can detect 100 ng/ml of IgG. The fast-flow filter paper was more sensitive than the medium-flow filter paper. The incubation period of this assay was short and required small sample volumes. This naked-eye, colorimetric immunoassay can be extended to detect other targets that are identified with conventional ELISA.

A distinct role of the queen in coordinated workload and soil distribution in eusocial naked mole-rats.

Directory of Open Access Journals (Sweden)

Nobuyuki Kutsukake

Full Text Available We investigated how group members achieve collective decision-making, by considering individual intrinsic behavioural rules and behavioural mechanisms for maintaining social integration. Using a simulated burrow environment, we investigated the behavioural rules of coordinated workload for soil distribution in a eusocial mammal, the naked mole-rat (Heterocephalus glaber. We tested two predictions regarding a distinct role of the queen, a socially dominant individual in the caste system: the presence of a queen would increase the workload of other caste individuals, and the cues by a queen would affect the soil distribution. In experiment 1, we placed four individuals of various castes from the same colony into an experimental burrow. Workers exhibited the highest frequency of workload compared to other castes. The presence of a queen activated the workload by other individuals. Individuals showed a consistent workload in a particular direction so as to bias the soil distribution. These results suggest that individuals have a consensus on soil distribution and that the queen plays a distinct role. In experiment 2, we placed the odour of a queen in one of four cells and observed its effect on other individuals' workload and soil distribution. Relative to other cells, individuals frequently dug in the queen cell so the amount of soil in the queen cell decreased. These results suggest that queen odour is an important cue in coordinated workload and soil distribution in this species.

Platyamoeba pseudovannellida n. sp., a naked amoeba with wide salt tolerance isolated from the Salton Sea, California.

Science.gov (United States)

Hauer, G; Rogerson, A; Anderson, O R

2001-01-01

A new species of naked amoeba, Platyamoeba pseudovannellida n.sp., is described on the basis of light microscopic and fine structural features. The amoeba was isolated from the Salton Sea, California, from water at a salinity of ca. 44%. Locomotive amoebae occasionally had a spatulate outline and floating cells had radiating pseudopodia, sometimes with pointed tips. Both these features are reminiscent of the genus Vannella. However, the surface coat (glycocalyx) as revealed by TEM indicates that this is a species of Platyamoeba. Although salinity was not used as a diagnostic feature, this species was found to have remarkable tolerance to fluctuating salinity levels, even when changes were rapid. Amoebae survived over the range 0 per thousand to 150 per thousand salt and grew within the range 0 per thousand to 138 per thousand salt. The generation time of cells averaged 29 h and was not markedly affected by salt concentration. This is longer than expected for an amoeba of this size and suggests a high energetic cost of coping with salinity changes. The morphology of cells changed with increasing salinity: at 0 per thousand cells were flattened and active and at the other extreme (138 per thousand) amoebae were wrinkled and domed and cell movement was very slow. At the ultrastructural level, the cytoplasm of cells grown at high salinity (98 per thousand was considerably denser than that of cells reared at 0 per thousand.

Controlled formation of Ni(DMG)2 microrods/tubes by manipulating the kinetics of chemical reactions and their application in naked-eye sensors.

Science.gov (United States)

Qin, Jianli; Wang, Bo; Zhang, Xiujuan; Zhang, Xiaohong

2012-08-01

We have demonstrated controlled preparation of Ni(DMG)2 microrods/tubes via chemical reaction method. By manipulating the reaction kinetics via the concentration of reactants, shapes of the resulting microstructures can be easily tuned from microrods to microtubes. Size of the resulting products can also be controlled through changing the reaction temperatures. It was proposed that under high reactants' concentrations, molecules will prefer to grow at corners or edges of nuclei with high free energies, to reduce the total energy in the system, which would lead to partial or complete hollow interiors and eventually resulted in mircotubes. The fact that DMG show high selectivity with Ni2+ and accompanied with obvious color change enable us to fabricate test strip for naked-eye detection of Ni2+. Benefit from the large surface areas of DMG nanoparticles on the test strip, the detection limit is improved by two orders over that of conventional solution method. This strategy is sensitive, simple and easy to handle, thus expected to possess potentials for the practical Ni2+ detection applications.

Basic instinct undressed: early spatiotemporal processing for primary sexual characteristics.

Directory of Open Access Journals (Sweden)

Lore B Legrand

Full Text Available This study investigates the spatiotemporal dynamics associated with conscious and non-conscious processing of naked and dressed human bodies. To this effect, stimuli of naked men and women with visible primary sexual characteristics, as well as dressed bodies, were presented to 20 heterosexual male and female participants while acquiring high resolution EEG data. The stimuli were either consciously detectable (supraliminal presentations or were rendered non-conscious through backward masking (subliminal presentations. The N1 event-related potential component was significantly enhanced in participants when they viewed naked compared to dressed bodies under supraliminal viewing conditions. More importantly, naked bodies of the opposite sex produced a significantly greater N1 component compared to dressed bodies during subliminal presentations, when participants were not aware of the stimulus presented. A source localization algorithm computed on the N1 showed that the response for naked bodies in the supraliminal viewing condition was stronger in body processing areas, primary visual areas and additional structures related to emotion processing. By contrast, in the subliminal viewing condition, only visual and body processing areas were found to be activated. These results suggest that naked bodies and primary sexual characteristics are processed early in time (i.e., <200 ms and activate key brain structures even when they are not consciously detected. It appears that, similarly to what has been reported for emotional faces, sexual features benefit from automatic and rapid processing, most likely due to their high relevance for the individual and their importance for the species in terms of reproductive success.

Transcriptome sequencing of the naked mole rat (Heterocephalus glaber and identification of hypoxia tolerance genes

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Bang Xiao

2017-12-01

Full Text Available The naked mole rat (NMR; Heterocephalus glaber is a small rodent species found in regions of Kenya, Ethiopia and Somalia. It has a high tolerance for hypoxia and is thus considered one of the most important natural models for studying hypoxia tolerance mechanisms. The various mechanisms underlying the NMR's hypoxia tolerance are beginning to be understood at different levels of organization, and next-generation sequencing methods promise to expand this understanding to the level of gene expression. In this study, we examined the sequence and transcript abundance data of the muscle transcriptome of NMRs exposed to hypoxia using the Illumina HiSeq 2500 system to clarify the possible genomic adaptive responses to the hypoxic underground surroundings. The RNA-seq raw FastQ data were mapped against the NMR genome. We identified 2337 differentially expressed genes (DEGs by comparison of the hypoxic and control groups. Functional annotation of the DEGs by gene ontology (GO analysis revealed enrichment of hypoxia stress-related GO categories, including ‘biological regulation’, ‘cellular process’, ‘ion transport’ and ‘cell-cell signaling’. Enrichment of DEGs in signaling pathways was analyzed against the Kyoto Encyclopedia of Genes and Genomes (KEGG database to identify possible interactions between DEGs. The results revealed significant enrichment of DEGs in focal adhesion, the mitogen-activated protein kinase (MAPK signaling pathway and the glycine, serine and threonine metabolism pathway. Furthermore, inhibition of DEGs (STMN1, MAPK8IP1 and MAPK10 expression induced apoptosis and arrested cell growth in NMR fibroblasts following hypoxia. Thus, this global transcriptome analysis of NMRs can provide an important genetic resource for the study of hypoxia tolerance in mammals. Furthermore, the identified DEGs may provide important molecular targets for biomedical research into therapeutic strategies for stroke and cardiovascular diseases.

A novel piperazine-bis(rhodamine-B)-based chemosensor for highly sensitive and selective naked-eye detection of Cu{sup 2+} and its application as an INHIBIT logic device

Energy Technology Data Exchange (ETDEWEB)

Sun, Zebin; Li, Haizhen; Guo, Dan; Liu, Yan; Tian, Zhang; Yan, Shiqiang, E-mail: yansq@lzu.edu.cn

2015-11-15

Abstact: We report the design and synthesis of a new piperazine-bis(rhodamine-B) (RB-P-RB)-based indicator for selective detection of Cu{sup 2+} ion. Optical sensing behavior toward various metal ions including alkali, alkaline earth and transition metal ions (Na{sup +}, K{sup +}, Ba{sup 2+}, Mg{sup 2+}, Ca{sup 2+}, Zn{sup 2+}, Cd{sup 2+}, Mn{sup 2+}, Co{sup 2+}, Ni{sup 2+}, Pb{sup 2+}, Cu{sup 2+}, Hg{sup 2+}, and Ag{sup +}) were investigated by UV–vis and fluorescence spectroscopy in ethassnol solution. The indicator showed highly selective and sensitive colorimetric and “turn-on” fluorescence enhancement responses toward Cu{sup 2+} ion owing to the ring-opening structure of the rhodamine spirolactam. The significant change from colorless to pink upon the addition of Cu{sup 2+} could make it a suitable “naked-eye” indicator for Cu{sup 2+}. Furthermore, a possible ring-opening mechanism (off-on) of the rhodamine spirolactam induced by Cu{sup 2+} binding is supported by Job plot, ESI-mass, FT-IR, and {sup 1}H NMR. More significantly, the probe displayed highly selective Cu{sup 2+}-amplified absorption in the presence of Cu{sup 2+} ions. Finally, using Cu{sup 2+} and EDTA as inputs and the fluorescence emission intensity as output, an INHIBIT logic gate can be constructed at the molecular level. - Highlights: • A novel piperazine-bis(rhodamine-B)-based sensor for selective detection of Cu{sup 2+} ion was synthesized via simple synthetic procedures. • The probe exhibited highly selective and sensitive colorimetric and “turn on” fluorescence enhancement responses to Cu{sup 2+}. • The probe can serve as a reversible and selective “naked eye” indicator for Cu{sup 2+} ions in ethanol solution. • The probe can be utilized to construct an INHIBIT logic gate at the molecular level. • The probe displays highly selective Cu{sup 2+}-amplified absorption in ethanol solution.

Beyond the galaxy how humanity looked beyond our milky way and discovered the entire Universe

CERN Document Server

Siegel, Ethan

2016-01-01

A look up at the night sky reveals a treasury of wonders. Even to the naked eye, the Moon, stars, planets, the Milky Way and even a few star clusters and nebulae illuminate the heavens. For millennia, humans struggled to make sense of what's out there in the Universe, from all we can see to that which lies beyond the limits of even our most powerful telescopes. Beyond the Galaxy traces our journey from an ancient, Earth-centered Universe all the way to our modern, 21st century understanding of the cosmos. Touching on not only what we know but also how we know it, Ethan Siegel takes us to the very frontiers of modern astrophysics and cosmology, from the birth of our Universe to its ultimate fate, and everything in between.

Characterization of the interaction between the human pathogen Listeria monocytogenes and the model host C. elegans

DEFF Research Database (Denmark)

Simonsen, Karina T.; Nielsen, Jesper S.; Hansen, Annie A.

In nature, C. elegans lives in the soil and feeds on bacteria. This constant contact with soil-borne microbes suggests that nematodes must have evolved protective responses against pathogens which makes the worm an attractive host-pathogen model for exploring their innate immune response....... In addition, C. elegans is a promising model for the identification of novel virulence factors in various pathogens. A large number of human, animal, plant and insect pathogens have been shown to kill the worm, when C. elegans was allowed to feed on pathogens in stead of its normal laboratory diet [1......]. However, the mechanisms that lead to the shortened life span of the worm have been shown to be very different depending on the nature of the pathogen. Examples include Yersinia pestis, which forms a biofilm layer on the cuticle of C. elegans thus inhibiting feeding [2], enteropathogenic Escherichia coli...

Ultrasound-mediated gene delivery of naked plasmid DNA in skeletal muscles: a case for bolus injections.

Science.gov (United States)

Sanches, Pedro Gomes; Mühlmeister, Mareike; Seip, Ralf; Kaijzel, Eric; Löwik, Clemens; Böhmer, Marcel; Tiemann, Klaus; Grüll, Holger

2014-12-10

Localized gene delivery has many potential clinical applications. However, the nucleic acids (e.g. pDNA and siRNA) are incapable of passively crossing the endothelium, cell membranes and other biological barriers which must be crossed to reach their intracellular targets. A possible solution is the use of ultrasound to burst circulating microbubbles inducing transient permeabilization of surrounding tissues which mediates nucleic acid extravasation and cellular uptake. In this study we report on an optimization of the ultrasound gene delivery technique. Naked pDNA (200 μg) encoding luciferase and SonoVue® microbubbles were co-injected intravenously in mice. The hindlimb skeletal muscles were exposed to ultrasound from a non-focused transducer (1 MHz, 1.25 MPa, PRI 30s) and injection protocols and total amounts as well as ultrasound parameters were systemically varied. Gene expression was quantified relative to a control using a bioluminescence camera system at day 7 after sonication. Bioluminescence ratios in sonicated/control muscles of up to 101× were obtained. In conclusion, we were able to specifically deliver genetic material to the selected skeletal muscles and overall, the use of bolus injections and high microbubble numbers resulted in increased gene expression reflected by stronger bioluminescence signals. Based on our data, bolus injections seem to be required in order to achieve transient highly concentrated levels of nucleic acids and microbubbles at the tissue of interest which upon ultrasound exposure should lead to increased levels of gene delivery. Thus, ultrasound mediated gene delivery is a promising technique for the clinical translation of localized drug delivery. Copyright © 2014 Elsevier B.V. All rights reserved.

Otolith microchemistry of modern versus well-dated ancient naked carp Gymnocypris przewalskii: Implication for water evolution of Lake Qinghai

Science.gov (United States)

Zhou, Ling; Jin, Zhangdong; Wang, Chia-Hui; Li, Fuchun; Wang, Yujiao; Wang, Xulong; Zhang, Fei; Chen, Liumei; Du, Jinhua

2015-06-01

There is ongoing debate over how the water level and composition of the water in Lake Qinghai changed in the past and might change in future. This study of the microchemistry of otoliths from ancient naked carp explores the chemistry of a relict lake isolated from Lake Qinghai during the Little Ice Age (LIA). A close correlation between the ages measured on fish bone and otoliths by AMS-14C, and by optically stimulated luminescence on overlying sediments, confirms a high water level in Lake Qinghai before 680-300 years ago. The contrasting compositions of the ancient otoliths relative to modern otoliths and waters indicate that the relict lake became enriched in 18O, Mg, Li, B and to a lesser extent Ba, but depleted in 13C, owing to strong evaporation, authigenic carbonates precipitation, (micro-)organism activity, and less fresh water input after it was isolated. If there were long-term fresh water input, however, a reverse trend might occur. The most important observation is that, because the waters have been supersaturated with respect to carbonates, authigenic carbonate precipitation would result in low but consistent Sr/Ca ratios in the lakes, as recorded by both the ancient and modern otoliths. The geochemical records of ancient versus modern biogenic carbonates provide insights into the long-term hydroclimatic evolution processes of an inland water body.

Investigation of scale effects and directionality dependence on friction and adhesion of human hair using AFM and macroscale friction test apparatus

International Nuclear Information System (INIS)

LaTorre, Carmen; Bhushan, Bharat

2006-01-01

Macroscale testing of human hair tribological properties has been widely used to aid in the development of better shampoos and conditioners. Recently, literature has focused on using the atomic force microscope (AFM) to study surface roughness, coefficient of friction, adhesive force, and wear (tribological properties) on the nanoscale in order to increase understanding about how shampoos and conditioners interact with the hair cuticle. Since there are both similarities and differences when comparing the tribological trends at both scales, it is thus recognized that scale effects are an important aspect of studying the tribology of hair. However, no microscale tribological data for hair exists in literature. This is unfortunate because many interactions between hair-skin, hair-comb, and hair-hair contact takes place at microasperities ranging from a few μm to hundreds of μm. Thus, to bridge the gap between the macro- and nanoscale data, as well as to gain a full understanding of the mechanisms behind the trends, it is now worthwhile to look at hair tribology on the microscale. Presented in this paper are coefficient of friction and adhesive force data on various scales for virgin and chemically damaged hair, both with and without conditioner treatment. Macroscale coefficient of friction was determined using a traditional friction test apparatus. Microscale and nanoscale tribological characterization was performed with AFM tips of various radii. The nano-, micro-, and macroscale trends are compared and the mechanisms behind the scale effects are discussed. Since the coefficient of friction changes drastically (on any scale) depending on whether the direction of motion is along or against the cuticle scales, the directionality dependence and responsible mechanisms are discussed

Dynamic maps of UV damage formation and repair for the human genome.

Science.gov (United States)

Hu, Jinchuan; Adebali, Ogun; Adar, Sheera; Sancar, Aziz

2017-06-27

Formation and repair of UV-induced DNA damage in human cells are affected by cellular context. To study factors influencing damage formation and repair genome-wide, we developed a highly sensitive single-nucleotide resolution damage mapping method [high-sensitivity damage sequencing (HS-Damage-seq)]. Damage maps of both cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts [(6-4)PPs] from UV-irradiated cellular and naked DNA revealed that the effect of transcription factor binding on bulky adducts formation varies, depending on the specific transcription factor, damage type, and strand. We also generated time-resolved UV damage maps of both CPDs and (6-4)PPs by HS-Damage-seq and compared them to the complementary repair maps of the human genome obtained by excision repair sequencing to gain insight into factors that affect UV-induced DNA damage and repair and ultimately UV carcinogenesis. The combination of the two methods revealed that, whereas UV-induced damage is virtually uniform throughout the genome, repair is affected by chromatin states, transcription, and transcription factor binding, in a manner that depends on the type of DNA damage.

Gene expression profiling of cuticular proteins across the moult cycle of the crab Portunus pelagicus

Directory of Open Access Journals (Sweden)

Kuballa Anna V

2007-10-01

Full Text Available Abstract Background Crustaceans represent an attractive model to study biomineralization and cuticle matrix formation, as these events are precisely timed to occur at certain stages of the moult cycle. Moulting, the process by which crustaceans shed their exoskeleton, involves the partial breakdown of the old exoskeleton and the synthesis of a new cuticle. This cuticle is subdivided into layers, some of which become calcified while others remain uncalcified. The cuticle matrix consists of many different proteins that confer the physical properties, such as pliability, of the exoskeleton. Results We have used a custom cDNA microarray chip, developed for the blue swimmer crab Portunus pelagicus, to generate expression profiles of genes involved in exoskeletal formation across the moult cycle. A total of 21 distinct moult-cycle related differentially expressed transcripts representing crustacean cuticular proteins were isolated. Of these, 13 contained copies of the cuticle_1 domain previously isolated from calcified regions of the crustacean exoskeleton, four transcripts contained a chitin_bind_4 domain (RR consensus sequence associated with both the calcified and un-calcified cuticle of crustaceans, and four transcripts contained an unannotated domain (PfamB_109992 previously isolated from C. pagurus. Additionally, cryptocyanin, a hemolymph protein involved in cuticle synthesis and structural integrity, also displays differential expression related to the moult cycle. Moult stage-specific expression analysis of these transcripts revealed that differential gene expression occurs both among transcripts containing the same domain and among transcripts containing different domains. Conclusion The large variety of genes associated with cuticle formation, and their differential expression across the crustacean moult cycle, point to the complexity of the processes associated with cuticle formation and hardening. This study provides a molecular entry path

Molecular analysis of formaldehyde-induced mutations in human lymphoblasts and E. coli

International Nuclear Information System (INIS)

Crosby, R.M.; Richardson, K.K.; Craft, T.R.; Benforado, K.B.; Liber, H.L.; Skopek, T.R.

1988-01-01

The molecular nature of formaldehyde (HCHO)-induced mutations was studied in both human lymphoblasts and E. coli. Thirty HPRT - human lymphoblast colonies induced by eight repetitive 150 μM HCHO treatments were characterized by Southern blot analysis. Fourteen of these mutants (47%) had visible deletions of some or all of the X-linked HPRT bands, indicating that HCHO can induce large losses of DNA in human lymphoblasts. In E. coli., DNA alterations induced by HCHO were characterized with use of the xanthine guanine phosphoribosyl transferase (gpt) gene as the genetic target. Exposure of E. coli to 4 mM HCHO for 1 hr induced large insertions (41%), large deletions (18%), and point mutations (41%). Dideoxy DNA sequencing revealed that most of the point mutations were transversions at GC base pairs. In contrast, exposure of E. coli to 40 mM HCHO for 1 hr produced 92% point mutations, 62% of which were transitions at a single AT base pair in the gene. Therefore, HCHO is capable of producing different genetic alterations in E. coli at different concentrations, suggesting fundamental differences in the mutagenic mechanisms operating at the two concentrations used. Naked pSV2gpt plasmid DNA was exposed to 3.3 or 10 mM HCHO and transformed into E. coli. Most of the resulting mutations were frameshifts, again suggesting a different mutagenic mechanism

Reduced Utilization of Selenium by Naked Mole Rats Due to a Specific Defect in GPx1 Expression*

Science.gov (United States)

Kasaikina, Marina V.; Lobanov, Alexei V.; Malinouski, Mikalai Y.; Lee, Byung Cheon; Seravalli, Javier; Fomenko, Dmitri E.; Turanov, Anton A.; Finney, Lydia; Vogt, Stefan; Park, Thomas J.; Miller, Richard A.; Hatfield, Dolph L.; Gladyshev, Vadim N.

2011-01-01

Naked mole rat (MR) Heterocephalus glaber is a rodent model of delayed aging because of its unusually long life span (>28 years). It is also not known to develop cancer. In the current work, tissue imaging by x-ray fluorescence microscopy and direct analyses of trace elements revealed low levels of selenium in the MR liver and kidney, whereas MR and mouse brains had similar selenium levels. This effect was not explained by uniform selenium deficiency because methionine sulfoxide reductase activities were similar in mice and MR. However, glutathione peroxidase activity was an order of magnitude lower in MR liver and kidney than in mouse tissues. In addition, metabolic labeling of MR cells with 75Se revealed a loss of the abundant glutathione peroxidase 1 (GPx1) band, whereas other selenoproteins were preserved. To characterize the MR selenoproteome, we sequenced its liver transcriptome. Gene reconstruction revealed standard selenoprotein sequences except for GPx1, which had an early stop codon, and SelP, which had low selenocysteine content. When expressed in HEK 293 cells, MR GPx1 was present in low levels, and its expression could be rescued neither by removing the early stop codon nor by replacing its SECIS element. In addition, GPx1 mRNA was present in lower levels in MR liver than in mouse liver. To determine if GPx1 deficiency could account for the reduced selenium content, we analyzed GPx1 knock-out mice and found reduced selenium levels in their livers and kidneys. Thus, MR is characterized by the reduced utilization of selenium due to a specific defect in GPx1 expression. PMID:21372135

A comparative study on low-energy ion beam and neutralized beam modifications of naked DNA and biological effect on mutation

Science.gov (United States)

Sarapirom, S.; Thongkumkoon, P.; Prakrajang, K.; Anuntalabhochai, S.; Yu, L. D.

2012-02-01

DNA conformation change or damage induced by low-energy ion irradiation has been of great interest owing to research developments in ion beam biotechnology and ion beam application in biomedicine. Mechanisms involved in the induction of DNA damage may account for effect from implanting ion charge. In order to check this effect, we used both ion beam and neutralized beam at keV energy to bombard naked DNA. Argon or nitrogen ion beam was generated and extracted from a radiofrequency (RF) ion source and neutralized by microwave-driven plasma in the beam path. Plasmid DNA pGFP samples were irradiated with the ion or neutralized beam in vacuum, followed by gel electrophoresis to observe changes in the DNA conformations. It was revealed that the ion charge played a certain role in inducing DNA conformation change. The subsequent DNA transfer into bacteria Escherichia coli ( E. coli) for mutation analysis indicated that the charged ion beam induced DNA change had high potential in mutation induction while neutralized beam did not. The intrinsic reason was attributed to additional DNA deformation and contortion caused by ion charge exchange effect so that the ion beam induced DNA damage could hardly be completely repaired, whereas the neutralized beam induced DNA change could be more easily recoverable owing to absence of the additional DNA deformation and contortion.

A comparative study on low-energy ion beam and neutralized beam modifications of naked DNA and biological effect on mutation

International Nuclear Information System (INIS)

Sarapirom, S.; Thongkumkoon, P.; Prakrajang, K.; Anuntalabhochai, S.; Yu, L.D.

2012-01-01

DNA conformation change or damage induced by low-energy ion irradiation has been of great interest owing to research developments in ion beam biotechnology and ion beam application in biomedicine. Mechanisms involved in the induction of DNA damage may account for effect from implanting ion charge. In order to check this effect, we used both ion beam and neutralized beam at keV energy to bombard naked DNA. Argon or nitrogen ion beam was generated and extracted from a radiofrequency (RF) ion source and neutralized by microwave-driven plasma in the beam path. Plasmid DNA pGFP samples were irradiated with the ion or neutralized beam in vacuum, followed by gel electrophoresis to observe changes in the DNA conformations. It was revealed that the ion charge played a certain role in inducing DNA conformation change. The subsequent DNA transfer into bacteria Escherichia coli (E. coli) for mutation analysis indicated that the charged ion beam induced DNA change had high potential in mutation induction while neutralized beam did not. The intrinsic reason was attributed to additional DNA deformation and contortion caused by ion charge exchange effect so that the ion beam induced DNA damage could hardly be completely repaired, whereas the neutralized beam induced DNA change could be more easily recoverable owing to absence of the additional DNA deformation and contortion.

Formation of the hindgut cuticular lining during embryonic development of Porcellio scaber (Crustacea, Isopoda

Directory of Open Access Journals (Sweden)

Polona Mrak

2015-07-01

Full Text Available The hindgut and foregut in terrestrial isopod crustaceans are ectodermal parts of the digestive system and are lined by cuticle, an apical extracellular matrix secreted by epithelial cells. Morphogenesis of the digestive system was reported in previous studies, but differentiation of the gut cuticle was not followed in detail. This study is focused on ultrastructural analyses of hindgut apical matrices and cuticle in selected intramarsupial developmental stages of the terrestrial isopod Porcellio scaber in comparison to adult animals to obtain data on the hindgut cuticular lining differentiation. Our results show that in late embryos of stages 16 and 18 the apical matrix in the hindgut consists of loose material overlaid by a thin intensely ruffled electron dense lamina facing the lumen. The ultrastructural resemblance to the embryonic epidermal matrices described in several arthropods suggests a common principle in chitinous matrix differentiation. The hindgut matrix in the prehatching embryo of stage 19 shows characteristics of the hindgut cuticle, specifically alignment to the apical epithelial surface and a prominent electron dense layer of epicuticle. In the preceding embryonic stage – stage 18 – an electron dense lamina, closely apposed to the apical cell membrane, is evident and is considered as the first epicuticle formation. In marsupial mancae the advanced features of the hindgut cuticle and epithelium are evident: a more prominent epicuticular layer, formation of cuticular spines and an extensive apical labyrinth. In comparison to the hindgut cuticle of adults, the hindgut cuticle of marsupial manca and in particular the electron dense epicuticular layer are much thinner and the difference between cuticle architecture in the anterior chamber and in the papillate region is not yet distinguishable. Differences from the hindgut cuticle in adults imply not fully developed structure and function of the hindgut cuticle in marsupial

The effect of polycarboxylate shell of magnetite nanoparticles on protein corona formation in blood plasma

Energy Technology Data Exchange (ETDEWEB)

Szekeres, Márta, E-mail: szekeres@chem.u-szeged.hu [Department of Physical Chemistry and Materials Sciences, University of Szeged, Hungary, 1 Aradi vt, 6720 Szeged (Hungary); Tóth, Ildikó Y. [Department of Physical Chemistry and Materials Sciences, University of Szeged, Hungary, 1 Aradi vt, 6720 Szeged (Hungary); Turcu, R. [National Institute R& D for Isotopic and Molecular Technology, Cluj-Napoca 400293 (Romania); Tombácz, Etelka [Department of Physical Chemistry and Materials Sciences, University of Szeged, Hungary, 1 Aradi vt, 6720 Szeged (Hungary)

2017-04-01

The development of protein corona around nanoparticles upon administration to the human body is responsible in a large part for their biodistribution, cell-internalization and toxicity or biocompatibility. We studied the influence of the chemical composition of polyelectrolyte shells (citric acid (CA) and poly(acrylic-co-maleic acid) (PAM)) of core-shell magnetite nanoparticles (MNPs) on the evolution of protein corona in human plasma (HP). The aggregation state and zeta potential of the particles were measured in the range of HP concentration between 1 and 80 (v/v)% 3 min and 20 h after dispersing the particles in HP diluted with Tris buffered saline. Naked MNPs aggregated in HP solution, but the carboxylated MNPs became stabilized colloidally at higher plasma concentrations. Significant differences were observed at low plasma concentration. CA@MNPs aggregated instantly while the hydrodynamic diameter of PAM@MNP increased only slightly at 1–3 v/v % HP concentrations. The observed differences in protein corona formation can be explained by the differences in the steric effects of the polycarboxylate shells. It is interesting that relatively small but systematic changes in zeta potential alter the aggregation state significantly. - Highlights: • Human plasma protein corona cannot stabilize naked and citrate-coated magnetite nanoparticles. • Polycarboxylic acid (PAM) coated MNPs are well stabilized with HP protein corona. • Stability pattern of naked, CA and PAM-coated MNPs is not predicted by zeta potential.

Recombinant Kunjin virus replicon vaccines induce protective T-cell immunity against human papillomavirus 16 E7-expressing tumour

International Nuclear Information System (INIS)

Herd, Karen A.; Harvey, Tracey; Khromykh, Alexander A.; Tindle, Robert W.

2004-01-01

The persistence of the E7 oncoprotein in transformed cells in human papillomavirus (HPV)-associated cervical cancer provides a tumour-specific antigen to which immunotherapeutic strategies may be directed. Self-replicating RNA (replicon) vaccine vectors derived from the flavivirus Kunjin (KUN) have recently been reported to induce T-cell immunity. Here, we report that inclusion of a CTL epitope of HPV16 E7 protein into a polyepitope encoded by a KUN vector induced E7-directed T-cell responses and protected mice against challenge with an E7-expressing epithelial tumour. We found replicon RNA packaged into virus-like particles to be more effective than naked replicon RNA or plasmid DNA constructed to allow replicon RNA transcription in vivo. Protective immunity was induced although the E7 CTL epitope was subdominant in the context of other CTL epitopes in the polyepitope. The results demonstrate the efficacy of the KUN replicon vector system for inducing protective immunity directed towards a virally encoded human tumour-specific antigen, and for inducing multi-epitopic CTL responses

Buckling as an origin of ordered cuticular patterns in flower petals

Science.gov (United States)

Antoniou Kourounioti, Rea L.; Band, Leah R.; Fozard, John A.; Hampstead, Anthony; Lovrics, Anna; Moyroud, Edwige; Vignolini, Silvia; King, John R.; Jensen, Oliver E.; Glover, Beverley J.

2013-01-01

The optical properties of plant surfaces are strongly determined by the shape of epidermal cells and by the patterning of the cuticle on top of the cells. Combinations of particular cell shapes with particular nanoscale structures can generate a wide range of optical effects. Perhaps most notably, the development of ordered ridges of cuticle on top of flat petal cells can produce diffraction-grating-like structures. A diffraction grating is one of a number of mechanisms known to produce ‘structural colours’, which are more intense and pure than chemical colours and can appear iridescent. We explore the concept that mechanical buckling of the cuticle on the petal epidermis might explain the formation of cuticular ridges, using a theoretical model that accounts for the development of compressive stresses in the cuticle arising from competition between anisotropic expansion of epidermal cells and isotropic cuticle production. Model predictions rationalize cuticle patterns, including those with long-range order having the potential to generate iridescence, for a range of different flower species. PMID:23269848

Non-additive non-interacting kinetic energy of rare gas dimers

Science.gov (United States)

Jiang, Kaili; Nafziger, Jonathan; Wasserman, Adam

2018-03-01

Approximations of the non-additive non-interacting kinetic energy (NAKE) as an explicit functional of the density are the basis of several electronic structure methods that provide improved computational efficiency over standard Kohn-Sham calculations. However, within most fragment-based formalisms, there is no unique exact NAKE, making it difficult to develop general, robust approximations for it. When adjustments are made to the embedding formalisms to guarantee uniqueness, approximate functionals may be more meaningfully compared to the exact unique NAKE. We use numerically accurate inversions to study the exact NAKE of several rare-gas dimers within partition density functional theory, a method that provides the uniqueness for the exact NAKE. We find that the NAKE decreases nearly exponentially with atomic separation for the rare-gas dimers. We compute the logarithmic derivative of the NAKE with respect to the bond length for our numerically accurate inversions as well as for several approximate NAKE functionals. We show that standard approximate NAKE functionals do not reproduce the correct behavior for this logarithmic derivative and propose two new NAKE functionals that do. The first of these is based on a re-parametrization of a conjoint Perdew-Burke-Ernzerhof (PBE) functional. The second is a simple, physically motivated non-decomposable NAKE functional that matches the asymptotic decay constant without fitting.

Reconstructed tree fern Alethopteris zeilleri (Carboniferous, Medullosales)

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, Sydney, Nova, Scotia (Canada B1P 6L2)

2007-01-02

From a smaller open-pit area in the roof shale of the basal Cantabrian coal seam in Sydney Coalfield, Cape Breton Island, Nova Scotia, Canada, large amounts of the pteridosperm foliage Alethopteris zeilleri (Ragot) were found. This foliage is associated with abundant, naked medullosalean axes and dichotomies of varying sizes, up to 0.80-m long, cauline structures 0.90 m and 1.3 m long, detached ovules assigned to Pachytesta incrassata Brongniart, rare male-pollen organs of the type Dolerotheca Halle, rooted tree ferns in life position, and one specimen each of a juvenile medullosalean frond and root mantle. The fossils are compression/impression-preserved, and the foliage yielded thickly cutinized cuticles with unoriented cells (57-103 by 27-57 {mu}m) in intercostal fields. Ultimate rachises, and abaxial surfaces (excluding costal fields) show a mixture of simple and complexly-branched trichomes, and two different structural bases. These, together with fractal dimensionality of curvatures of anticlinal walls in intercostal fields, have taxonomic potential for alethopterids. The finds suggest reconstructing A. zeilleri (Ragot) as a tree, 5-7 m high, that bore both P. incrassata Brongniart and Dolerotheca-type fructifications. Its habitat was low-land coastal plains in the Pennsylvanian coal swamps of ancestral Sydney Coalfield. (author)

In vivo chemical and structural analysis of plant cuticular waxes using stimulated Raman scattering microscopy.

Science.gov (United States)

Littlejohn, George R; Mansfield, Jessica C; Parker, David; Lind, Rob; Perfect, Sarah; Seymour, Mark; Smirnoff, Nicholas; Love, John; Moger, Julian

2015-05-01

The cuticle is a ubiquitous, predominantly waxy layer on the aerial parts of higher plants that fulfils a number of essential physiological roles, including regulating evapotranspiration, light reflection, and heat tolerance, control of development, and providing an essential barrier between the organism and environmental agents such as chemicals or some pathogens. The structure and composition of the cuticle are closely associated but are typically investigated separately using a combination of structural imaging and biochemical analysis of extracted waxes. Recently, techniques that combine stain-free imaging and biochemical analysis, including Fourier transform infrared spectroscopy microscopy and coherent anti-Stokes Raman spectroscopy microscopy, have been used to investigate the cuticle, but the detection sensitivity is severely limited by the background signals from plant pigments. We present a new method for label-free, in vivo structural and biochemical analysis of plant cuticles based on stimulated Raman scattering (SRS) microscopy. As a proof of principle, we used SRS microscopy to analyze the cuticles from a variety of plants at different times in development. We demonstrate that the SRS virtually eliminates the background interference compared with coherent anti-Stokes Raman spectroscopy imaging and results in label-free, chemically specific confocal images of cuticle architecture with simultaneous characterization of cuticle composition. This innovative use of the SRS spectroscopy may find applications in agrochemical research and development or in studies of wax deposition during leaf development and, as such, represents an important step in the study of higher plant cuticles. © 2015 American Society of Plant Biologists. All Rights Reserved.

Feasibilty of in utero DNA vaccination following naked gene transfer into pig fetal muscle: transgene expression, immunity and safety.

Science.gov (United States)

Rinaldi, Monica; Signori, Emanuela; Rosati, Paolo; Cannelli, Giorgio; Parrella, Paola; Iannace, Enrico; Monego, Giovanni; Ciafrè, Silvia Anna; Farace, Maria Giulia; Iurescia, Sandra; Fioretti, Daniela; Rasi, Guido; Fazio, Vito Michele

2006-05-22

The high toll of death among first-week infants is due to infections occurring at the end of pregnancy, during birth or by breastfeeding. This problem significantly concerns industrialized countries also. To prevent the typical "first-week infections", a vaccine would be protective as early as at the birth. In utero DNA immunization has demonstrated the effectiveness in inducing specific immunity in newborns. We have already published results of a 2-year follow-up showing long-term safety, protective antibody titers at birth and long-term immune memory, following intramuscular in utero anti-HBV DNA immunization in 90-days pig fetuses. We have now analyzed further parameters of short-term safety. Two different reporter genes were injected in the thigh muscles of 90-days fetuses. At 8 days following DNA injection, we found high-level of transgenes expression in all injected fetuses. A step gradient of expression from the area of injection was observed with both reporter genes. CMV promoter/enhancer produced higher levels of expression compared to SV40 promoter/enhancer. Moreover, no evidence of local or systemic flogistic alterations or fetal malformations, mortality or haemorrhage following intramuscular injection were observed. A single anti-HBV s-antigen DNA immunization in 90-days fetuses supported protective antibody levels in all immunized newborns, lasting at least up to 4 months after birth. Our report further sustains safety and efficacy of intramuscular in utero naked gene transfer and immunization. This approach may support therapeutic or prophylactic procedure in many early life-threatening pathologic conditions.

Rapid mounting of adult Drosophila structures in Hoyer's medium.

Science.gov (United States)

Stern, David L; Sucena, Elio

2012-01-01

The Drosophila cuticle carries a rich array of morphological details. Thus, cuticle examination has had a central role in the history of genetics. This protocol describes a procedure for mounting adult cuticles in Hoyer's medium, a useful mountant for both larval and adult cuticles. The medium digests soft tissues rapidly, leaving the cuticle cleared for observation. In addition, samples can be transferred directly from water to Hoyer's medium. However, specimens mounted in Hoyer's medium degrade over time. For example, the fine denticles on the larval dorsum are best observed soon after mounting; they begin to fade after 1 week, and can disappear completely after several months. More robust features, such as the ventral denticle belts, will persist for a longer period of time. Because adults cannot profitably be mounted whole in Hoyer's medium, some dissection is necessary.

A simple, reversible, colorimetric and water-soluble fluorescent chemosensor for the naked-eye detection of Cu2 + in 100% aqueous media and application to real samples

Science.gov (United States)

Sun, Tao; Niu, Qingfen; Li, Tianduo; Guo, Zongrang; Liu, Haixia

2018-01-01

A simple, reversible, colorimetric and water-soluble fluorescent chemosensor ADA for the naked-eye detection of Cu2 + was developed. Sensor ADA showed high selectivity and sensitivity toward Cu2 + in 100% aqueous media over wide pH range. Sensor ADA exhibited a red-shift in the absorption spectra from 466 to 480 nm that is accompanied by significant color change from light yellow to yellowish brown instantaneously. The Cu2 + recognition is based on the chelation-enhanced fluorescence quenching (CHEQ) effect of the paramagnetic nature. The lowest detection limit is determined to be 15.8 nM, which is much lower than the allowable level of Cu2 + in drinking water set by U.S. Environmental Protection Agency ( 20 μM) and the World Health Organization ( 30 μM). The 1:1 binding process was confirmed by fluorescence measurements, IR analysis and DFT studies. Moreover, sensor ADA was successfully applied for determination of trace level of Cu2 + with 4 reuse cycles in various water samples, which affords promising potential in ion-detection field.

THE “NAKED FACE” OF SECULAR EXCLUSION: BILL 94 AND THE PRIVATIZATION OF BELIEF

Directory of Open Access Journals (Sweden)

Pascale Fournier

2012-02-01

Full Text Available This article will consider the case study of Québec’s Bill 94 (An Act to establish guidelines governing accommodation requests within the Administration and certain institutions, introduced in March 2010, one of many recent bans imposed on the wearing of the niqab in the West. Citing the importance of “the right to gender equality and the principle of religious neutrality of the State,” Bill 94 emphasizes the necessity of “un visage découvert” or “naked face” when giving or receiving a broad range of public services in Québec, including all government services, childcare centres, hospitals, and health and social service agencies. According to section 6 of the Act, “If an accommodation involves an adaptation of that practice and reasons of security, communication or identification warrant it, the accommodation must be denied.” While quasi-neutral, this bill clearly has a disproportionate impact on religious women who wear the niqab. In fact, as a direct result of the legislation, Muslim women will likely disappear from the public sphere and be restricted to the private home where they might effectively be dependent on male family members to navigate the “market place” on their behalf. Borrowing from Charles Taylor’s A Secular Age, this paper will consider the distributive consequences of the niqab ban, a critical juncture of “religion-state relations” in which belief is more and more relegated to the private sphere in Quebec. The article will use Bill 94 to explore this peculiar manifestation of “secularism” with the concurrent existence of “governance feminism”— how the privatization of belief goes hand in hand and is perversely reinforced by a colonial discourse on gender equality, leaving some already marginalized women out of the public gaze. Is this legislated demand for a “naked face” truly the logical outcome of a successful feminist movement (as some have asserted or isthis erasure of religious

Bloodstains on Leather: Examination of False Negatives in Presumptive Test and Human Hemoglobin Test.

Science.gov (United States)

Castelló, Ana; Francès, Francesc; Verdú, Fernando

2017-09-01

Presumptive tests for blood are very simple and sensitive tests used in the search for evidence. They also provide initial information on the nature of stains. A second test can confirm their nature. However, these tests can present false-negative results for different reasons. Some of those reasons have been studied, while others, those caused by the substrate material that contains the stain, are less well known. This work studies the effect of one component of a leather substrate-quebracho extract-on presumptive and human hemoglobin blood tests. Assays were performed using samples of blood dilutions contaminated with quebracho extract and others formed on a substrate containing the contaminant. Results show an undoubted interference that causes false negatives and even visible to the naked eye stains and also indicate that some tests (phenolphthalein) are more affected than others. Examiners should be taken into account when working on this kind of substrates. © 2017 American Academy of Forensic Sciences.

Absorption of human skin and its detecting platform in the process of laser cosmetology

Science.gov (United States)

Zhang, Yong-Lin; Ouyang, Li; Wang, Yang

2000-10-01

Because of the melanin, hemoglobin and water molecules, etc. contained, light absorption of human skin tissue changes with wavelength of light. This is the principle used in laser cosmetology for treating pigment diseases and vascular lesion diseases as well as skin decoration such as body tattooing, eyebrow tattooing, etc. The parameters of treatment used in laser cosmetology principally come from the research of the skin tissue optical characteristics of whites, and it is not suitable for the Oriental. The absorption spectrum of yellow race alive skin has been researched. The detecting platform for use in the measuring of vivi-tissue absorption spectrum has been developed which using opto-electronic nondestructive testing and virtual instrument techniques. The degree of pathological changes of skin can be detected by this platform also, thus the shortcoming of dosage selection in laser clinical treatments which have been decided only by naked eye observation and past experience of doctors can be solved.

Diabetes-associated dry eye syndrome in a new humanized transgenic model of type 1 diabetes.

Science.gov (United States)

Imam, Shahnawaz; Elagin, Raya B; Jaume, Juan Carlos

2013-01-01

Patients with Type 1 Diabetes (T1D) are at high risk of developing lacrimal gland dysfunction. We have developed a new model of human T1D using double-transgenic mice carrying HLA-DQ8 diabetes-susceptibility haplotype instead of mouse MHC-class II and expressing the human beta cell autoantigen Glutamic Acid Decarboxylase in pancreatic beta cells. We report here the development of dry eye syndrome (DES) after diabetes induction in our humanized transgenic model. Double-transgenic mice were immunized with DNA encoding human GAD65, either naked or in adenoviral vectors, to induce T1D. Mice monitored for development of diabetes developed lacrimal gland dysfunction. Animals developed lacrimal gland disease (classically associated with diabetes in Non Obese Diabetic [NOD] mice and with T1D in humans) as they developed glucose intolerance and diabetes. Animals manifested obvious clinical signs of dry eye syndrome (DES), from corneal erosions to severe keratitis. Histological studies of peri-bulbar areas revealed lymphocytic infiltration of glandular structures. Indeed, infiltrative lesions were observed in lacrimal/Harderian glands within weeks following development of glucose intolerance. Lesions ranged from focal lymphocytic infiltration to complete acinar destruction. We observed a correlation between the severity of the pancreatic infiltration and the severity of the ocular disease. Our results demonstrate development of DES in association with antigen-specific insulitis and diabetes following immunization with clinically relevant human autoantigen concomitantly expressed in pancreatic beta cells of diabetes-susceptible mice. As in the NOD mouse model and as in human T1D, our animals developed diabetes-associated DES. This specific finding stresses the relevance of our model for studying these human diseases. We believe our model will facilitate studies to prevent/treat diabetes-associated DES as well as human diabetes.

Secreted Frizzled-related protein-2 (sFRP2) augments canonical Wnt3a-induced signaling

Energy Technology Data Exchange (ETDEWEB)

Marschall, Zofia von [Craniofacial and Skeletal Diseases Branch, NIDCR, NIH, DHHS, Bethesda, MD (United States); Fisher, Larry W., E-mail: lfisher@dir.nidcr.nih.gov [Craniofacial and Skeletal Diseases Branch, NIDCR, NIH, DHHS, Bethesda, MD (United States)

2010-09-24

Research highlights: {yields} sFRP2 enhances the Wnt3a-induced {beta}-catenin stabilization and its nuclear translocation. {yields} sFRP2 enhances LRP6 phosphorylation and Wnt3a/{beta}-catenin transcriptional reporter activity. {yields} Dickkopf-1 (DKK1) fully antagonizes both Wnt3a/sFRP2-induced LRP6 phosphorylation and transcriptional activity. {yields} sFRP2 enhances expression of genes known to be regulated by Wnt3a signaling. -- Abstract: Secreted Frizzled-related proteins (sFRP) are involved in embryonic development as well as pathological conditions including bone and myocardial disorders and cancer. Because of their sequence homology with the Wnt-binding domain of Frizzled, they have generally been considered antagonists of canonical Wnt signaling. However, additional activities of various sFRPs including both synergism and mimicry of Wnt signaling as well as functions other than modulation of Wnt signaling have been reported. Using human embryonic kidney cells (HEK293A), we found that sFRP2 enhanced Wnt3a-dependent phosphorylation of LRP6 as well as both cytosolic {beta}-catenin levels and its nuclear translocation. While addition of recombinant sFRP2 had no activity by itself, Top/Fop luciferase reporter assays showed a dose-dependent increase of Wnt3a-mediated transcriptional activity. sFRP2 enhancement of Wnt3a signaling was abolished by treatment with the Wnt antagonist, Dickkopf-1 (DKK1). Wnt-signaling pathway qPCR arrays showed that sFRP2 enhanced the Wnt3a-mediated transcriptional up-regulation of several genes regulated by Wnt3a including its antagonists, DKK1, and Naked cuticle-1 homolog (NKD1). These results support sFRP2's role as an enhancer of Wnt/{beta}-catenin signaling, a result with biological impact for both normal development and diverse pathologies such as tumorigenesis.

Secreted Frizzled-related protein-2 (sFRP2) augments canonical Wnt3a-induced signaling

International Nuclear Information System (INIS)

Marschall, Zofia von; Fisher, Larry W.

2010-01-01

Research highlights: → sFRP2 enhances the Wnt3a-induced β-catenin stabilization and its nuclear translocation. → sFRP2 enhances LRP6 phosphorylation and Wnt3a/β-catenin transcriptional reporter activity. → Dickkopf-1 (DKK1) fully antagonizes both Wnt3a/sFRP2-induced LRP6 phosphorylation and transcriptional activity. → sFRP2 enhances expression of genes known to be regulated by Wnt3a signaling. -- Abstract: Secreted Frizzled-related proteins (sFRP) are involved in embryonic development as well as pathological conditions including bone and myocardial disorders and cancer. Because of their sequence homology with the Wnt-binding domain of Frizzled, they have generally been considered antagonists of canonical Wnt signaling. However, additional activities of various sFRPs including both synergism and mimicry of Wnt signaling as well as functions other than modulation of Wnt signaling have been reported. Using human embryonic kidney cells (HEK293A), we found that sFRP2 enhanced Wnt3a-dependent phosphorylation of LRP6 as well as both cytosolic β-catenin levels and its nuclear translocation. While addition of recombinant sFRP2 had no activity by itself, Top/Fop luciferase reporter assays showed a dose-dependent increase of Wnt3a-mediated transcriptional activity. sFRP2 enhancement of Wnt3a signaling was abolished by treatment with the Wnt antagonist, Dickkopf-1 (DKK1). Wnt-signaling pathway qPCR arrays showed that sFRP2 enhanced the Wnt3a-mediated transcriptional up-regulation of several genes regulated by Wnt3a including its antagonists, DKK1, and Naked cuticle-1 homolog (NKD1). These results support sFRP2's role as an enhancer of Wnt/β-catenin signaling, a result with biological impact for both normal development and diverse pathologies such as tumorigenesis.

Exoskeletal proteins from the crab, Cancer pagurus

DEFF Research Database (Denmark)

Andersen, Svend Olav

1999-01-01

Crustacea; decapods; cuticle; exoskeleton; structural protein; amino acid sequence; mass spectrometry......Crustacea; decapods; cuticle; exoskeleton; structural protein; amino acid sequence; mass spectrometry...

Immunohistochemical characterization of the chemosensory pulmonary neuroepithelial bodies in the naked mole-rat reveals a unique adaptive phenotype.

Science.gov (United States)

Pan, Jie; Park, Thomas J; Cutz, Ernest; Yeger, Herman

2014-01-01

The pulmonary neuroepithelial bodies (NEBs) constitute polymodal airway chemosensors for monitoring and signaling ambient gas concentrations (pO2, pCO2/H+) via complex innervation to the brain stem controlling breathing. NEBs produce the bioactive amine, serotonin (5-HT), and a variety of peptides with multiple effects on lung physiology and other organ systems. NEBs in mammals appear prominent and numerous during fetal and neonatal periods, and decline in the post-natal period suggesting an important role during perinatal adaptation. The naked mole-rat (NMR), Heterocephalus glaber, has adapted to the extreme environmental conditions of living in subterranean burrows in large colonies (up to 300 colony mates). The crowded, unventilated burrows are environments of severe hypoxia and hypercapnia. However, NMRs adjust readily to above ground conditions. The chemosensory NEBs of this species were characterized and compared to those of the conventional Wistar rat (WR) to identify similarities and differences that could explain the NMR's adaptability to environments. A multilabel immunohistochemical analysis combined with confocal microscopy revealed that the expression patterns of amine, peptide, neuroendocrine, innervation markers and chemosensor component proteins in NEBs of NMR were similar to that of WR. However, we found the following differences: 1) NEBs in both neonatal and adult NMR lungs were significantly larger and more numerous as compared to WR; 2) NEBs in NMR had a more variable compact cell organization and exhibited significant differences in the expression of adhesion proteins; 3) NMR NEBs showed a significantly greater ratio of 5-HT positive cells with an abundance of 5-HT; 4) NEBs in NMR expressed the proliferating cell nuclear antigen (PCNA) and the neurogenic gene (MASH1) indicating active proliferation and a state of persistent differentiation. Taken together our findings suggest that NEBs in lungs of NMR are in a hyperactive, functional and

Study of exogenous factors on the state and properties of hair on the human head by using various methods of microscopy

Directory of Open Access Journals (Sweden)

Neofitova E.A.

2016-12-01

Full Text Available in the article the effect of exogenous factors on the state and properties of hair on the human head using various techniques of microscopy as well as other morphometric methods are studied; on the basis of experimental samples the physical properties of healthy hair and the hair damaged by external factors by using microscopy techniques were compared; the article presents the values of pH and the content of surfactants (sulfates in different brands of shampoos and soaps, and their impact on the condition of the hair was determined; on the basis of microscopy techniques the condition of the cuticle after using different detergents for hair care was characterized; a relationship between the color of the hair and the influence of external factors on the structure and condition of the hair was analyzed; the signs of the impact of external factors (chemical, thermal, mechanical on the state and structure of the hair, using an optical (light and an usb-microscopes were identified.

Effect of particle size on solubility, dissolution rate, and oral bioavailability: evaluation using coenzyme Q10 as naked nanocrystals

Directory of Open Access Journals (Sweden)

Sun J

2012-11-01

Full Text Available Jiao Sun,1 Fan Wang,1,2 Yue Sui,1 Zhennan She,1 Wenjun Zhai,1 Chunling Wang,1 Yihui Deng11College of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China; 2Beijing Zhijianjinrui Applied Pharmaceutical Science Inc, Beijing, ChinaAbstract: In this paper work, four naked nanocrystals (size range 80–700 nm were prepared without any surfactant or polymer using the solvent/nonsolvent method. The effects of particle size on their solubility, dissolution, and oral bioavailability were investigated. Solubility and dissolution testing were performed in three types of dissolution medium, and the studies demonstrated that the equilibrium solubilities of coenzyme Q10 nanocrystals and bulk drugs were not affected by the dissolution media but the kinetic solubilities were. Kinetic solubility curves and changes in particle size distribution were determined and well explained by the proposed solubilization model for the nanocrystals and bulk drugs. The particle size effect on dissolution was clearly influenced by the diffusion coefficients of the various dissolution media, and the dissolution velocity of coenzyme Q10 increased as particle size decreased. The bioavailability of coenzyme Q10 after oral administration in beagle dogs was improved by reducing the particle size. For 700 nm nanocrystals, the AUC0–48 was 4.4-fold greater than that for the coarse suspensions, but a further decrease in particle size from 700 nm to 120 nm did not contribute to improvement in bioavailability until the particle size was reduced to 80 nm, when bioavailability was increased by 7.3-fold.Keywords: particle size, solubility, dissolution, nanocrystal, bioavailability, coenzyme Q10

Rhodamine B immobilized on hollow Au-HMS material for naked-eye detection of Hg{sup 2+} in aqueous media

Energy Technology Data Exchange (ETDEWEB)

Zhang, Na [State Key Laboratory of Fine Chemicals, College of Chemical Engineering, Dalian University of Technology, Dalian, 116024 (China); Li, Gang, E-mail: liganghg@dlut.edu.cn [State Key Laboratory of Fine Chemicals, College of Chemical Engineering, Dalian University of Technology, Dalian, 116024 (China); Cheng, Zhuhong [State Key Laboratory of Fine Chemicals, College of Chemical Engineering, Dalian University of Technology, Dalian, 116024 (China); Zuo, Xiujin [Key Laboratory of Bio-organic Chemistry, College of Environmental and Chemical Engineering, Dalian University, Dalian, 116622 (China)

2012-08-30

Graphical abstract: Au-HMS-Probe with worm-like mesoporous framework for detection of Hg{sup 2+} in aqueous media has been simply and effectively synthesized by immobilizing a Rhodamine B derivative on Au-HMS via Au-N groups under room temperature. Highlights: Black-Right-Pointing-Pointer Au-HMS-Probe is prepared via Au-N bonds. Black-Right-Pointing-Pointer Gold nanoparticles are chosen as connectors instead of silane agents. Black-Right-Pointing-Pointer Au-HMS is chosen as carrier for the first time. Black-Right-Pointing-Pointer The immobilization method of Au-HMS-Probe is very simple and effective. Black-Right-Pointing-Pointer Au-HMS-Probe shows excellent ability for detecting Hg{sup 2+} by naked-eye. - Abstract: A simple, effective method has been demonstrated to immobilize Rhodamine B (RhB) probes on mesoporous silica (Au-HMS). The prepared chemosensor (Au-HMS-Probe) was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), UV-vis spectrum and Fourier transform infrared spectroscopy (FT-IR). Further application of Au-HMS-Probe in sensing Hg{sup 2+} was confirmed by fluorescence titration experiment. Au-HMS-Probe afforded 'turn-on' fluorescence enhancement and displayed high brightness in water, and it also showed excellent selectivity for Hg{sup 2+} over alkali (Na{sup +}, K{sup +}), alkaline earth (Mg{sup 2+}, Ca{sup 2+}) and other heavy metal ions (Ag{sup +}, Cd{sup 2+}, Co{sup 2+}, Pb{sup 2+}, Ni{sup 2+}, Cu{sup 2+}, Fe{sup 2+}). Importantly, Au-HMS-Probe could be regenerated by treatment with tetrapropylammonium hydroxide solution.

Near-infrared chemodosimetric probes based on heptamethine cyanine dyes for the “naked-eye” detection of cyanide in aqueous media

Energy Technology Data Exchange (ETDEWEB)

Qiu, Dali [College of Chemistry, Xiangtan University, Xiangtan 411105, Hunan Province (China); Liu, Yijiang, E-mail: liuyijiang84@iccas.ac.cn [College of Chemistry, Xiangtan University, Xiangtan 411105, Hunan Province (China); Li, Mengnan [State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Chen, Hongbiao, E-mail: chhb606@163.com [College of Chemistry, Xiangtan University, Xiangtan 411105, Hunan Province (China); Li, Huaming [College of Chemistry, Xiangtan University, Xiangtan 411105, Hunan Province (China)

2017-05-15

Two simple chemodosimetric probes (P1 and P2) based on heptamethine cyanine dyes have been synthesized for highly sensitive and selective detection of cyanide anions (CN{sup −}) in aqueous media. The probes with an immobilized indolium salt as the specifically nucleophilic addition reaction site for CN{sup −} exhibit absorption bands in the near-infrared (NIR) region (650–850 nm). Upon the addition of CN{sup −}, the probes display a blue-shifted spectrum and result in apparent color change from green to brilliant yellow that can be easily observed by the naked eye even in the presence of other interfering anions such as F{sup −}, AcO{sup −}, Br{sup −}, NO{sub 2}{sup −}, Cl{sup −}, SO{sub 4}{sup 2−} and I{sup −}. There are good linear relationships between the fluorescence intensity of the probes and CN{sup −} concentrations, and the detection limits for P1 and P2 are estimated to be 0.017 μM and 0.2 μM, respectively. The sensing mechanism of the nucleophilic addition is confirmed by {sup 1}H NMR and mass spectroscopic analysis. In addition, the probe P2 is employed for cell imaging and the detection of CN{sup −} in living cells L929 is successfully realized. - Graphical abstract: Simple chemodosimetric probes based on heptamethine cyanine dye were synthesized and applied to detect CN{sup −} in aqueous media with colorimetric and fluorescent dual channel recognition.

Effectively simultaneous naked-eye detection of Cu(II), Pb(II), Al(III) and Fe(III) using cyanidin extracted from red cabbage as chelating agent

Science.gov (United States)

Khaodee, Warangkhana; Aeungmaitrepirom, Wanlapa; Tuntulani, Thawatchai

Simultaneous determination of Cu(II), Pb(II), Al(III) and Fe(III) using cyanidin as a chelating agent was investigated in terms of both quantitative and qualitative detections. Cyanidin was extracted and purified from red cabbage which is a local plant in Thailand. The selectivity of this method was examined by regulating the pH of cyanidin solution operated together with masking agents. It was found that Cu(II), Pb(II), Al(III) and Fe(III) simultaneously responded with the color change at pH 7, pH 6, pH 5 and pH 4, respectively. KF, DMG and the mixture of KF and DMG were used as masking agents for the determination of Fe(III), Al(III) and Pb(II), respectively. Results from naked-eye detection were evaluated by comparing with those of inductively coupled plasma (ICP), and there was no significant difference noticed. Cyanidin using as a multianalyte reagent could be employed for simultaneous determination of Cu(II), Pb(II), Al(III) and Fe(III) at the lowest concentration at 50, 80, 50 and 200 μM, respectively, by slightly varying pHs. Moreover, the proposed method could be potentially applied for real water samples with simplicity, rapidity, low cost and environmental safety.

Mechanical Control of Whole Body Shape by a Single Cuticular Protein Obstructor-E in Drosophila melanogaster.

Directory of Open Access Journals (Sweden)

Reiko Tajiri

2017-01-01

Full Text Available Body shapes are much more variable than body plans. One way to alter body shapes independently of body plans would be to mechanically deform bodies. To what extent body shapes are regulated physically, or molecules involved in physical control of morphogenesis, remain elusive. During fly metamorphosis, the cuticle (exoskeleton covering the larval body contracts longitudinally and expands laterally to become the ellipsoidal pupal case (puparium. Here we show that Drosophila melanogaster Obstructor-E (Obst-E is a protein constituent of the larval cuticle that confers the oriented contractility/expandability. In the absence of obst-E function, the larval cuticle fails to undergo metamorphic shape change and finally becomes a twiggy puparium. We present results indicating that Obst-E regulates the arrangement of chitin, a long-chain polysaccharide and a central component of the insect cuticle, and directs the formation of supracellular ridges on the larval cuticle. We further show that Obst-E is locally required for the oriented shape change of the cuticle during metamorphosis, which is associated with changes in the morphology of those ridges. Thus, Obst-E dramatically affects the body shape in a direct, physical manner by controlling the mechanical property of the exoskeleton.

Effect of production system and flock age on eggshell and egg internal quality measurements.

Science.gov (United States)

Samiullah, Sami; Omar, Amal Saleh; Roberts, Juliet; Chousalkar, Kapil

2017-01-01

Egg quality was measured in eggs from different flocks that were reared together and then allocated to different production systems. Eggs were processed for measurements of eggshell and egg internal quality variables, scoring of ultrastructural mammillary layer features, completeness of cuticle cover, and protoporphyrin IX (PP IX) quantification. There was a significant main effect (P egg weight, and egg internal quality and significant effects of flock age on most measurements. The mammillary layer ultrastructural variables showed no clear relationship with production system and flock age. However, there was a significant interaction between production system and flock age for mammillary cap, early and late fusions. Cuticle cover ([Formula: see text]), was significantly higher in barn eggs (19.20), followed by free range (17.57), and cage eggs (15.99). Completeness of cuticle cover was significantly higher in eggs from the 44 week old flock than for 64 week and 73 week old flocks. For eggshells with cuticle intact, there was a significant main effect of both production system and flock age, and significant interaction between the two, for shell reflectivity, L*a*b* values and amount of PP IX. For PP IX, when this difference was calculated for the cuticle alone, there were no statistically significant differences. In 1 g of shell with and without cuticle, there was more PP IX in cage eggs (9.49 × 10 -8 , 7.90 × 10 -8  mM) followed by free range (8.24 × 10 -8 , 6.90 × 10 -8  mM), and barn eggs (8.64 × 10 -8 , 7.28 × 10 -8  mM). Similar trends were recorded for the amount of PP IX in 1 g of cuticle, but the difference was not statistically significant. The amount of PP IX decreased significantly with increasing flock age. Comparing the cage and barn production systems at 68 week of flock age, there was no difference for the amount of PP IX in shell with or without cuticle, or in the cuticle alone. Eggs from the cage production system were darker in color

A simple, reversible, colorimetric and water-soluble fluorescent chemosensor for the naked-eye detection of Cu2+ in ~100% aqueous media and application to real samples.

Science.gov (United States)

Sun, Tao; Niu, Qingfen; Li, Tianduo; Guo, Zongrang; Liu, Haixia

2018-01-05

A simple, reversible, colorimetric and water-soluble fluorescent chemosensor ADA for the naked-eye detection of Cu 2+ was developed. Sensor ADA showed high selectivity and sensitivity toward Cu 2+ in ~100% aqueous media over wide pH range. Sensor ADA exhibited a red-shift in the absorption spectra from 466 to 480nm that is accompanied by significant color change from light yellow to yellowish brown instantaneously. The Cu 2+ recognition is based on the chelation-enhanced fluorescence quenching (CHEQ) effect of the paramagnetic nature. The lowest detection limit is determined to be 15.8nM, which is much lower than the allowable level of Cu 2+ in drinking water set by U.S. Environmental Protection Agency (~20μM) and the World Health Organization (~30μM). The 1:1 binding process was confirmed by fluorescence measurements, IR analysis and DFT studies. Moreover, sensor ADA was successfully applied for determination of trace level of Cu 2+ with 4 reuse cycles in various water samples, which affords promising potential in ion-detection field. Copyright © 2017 Elsevier B.V. All rights reserved.

Sustainable Utilization of Bio waste towards the Green Synthesis of Nanoparticles and its Utility in the Naked Eye Detection of Metals Coupled with its Larvicidal and Antimicrobial Properties

Science.gov (United States)

Nikhila, P. S.; Satheesh, Namitha; Sreejitha, V. S.; Pillai, Anandu R.; Saritha, A.; Smitha Chandran, S.

2018-02-01

Green synthesis of nanoparticles has become a prominent zone of attention in the field of nanotechnology, as it is a nontoxic, economically feasible and green approach. In the present work we have developed an eco-friendly and zero cost method for the synthesis of silver nanoparticles using common a bio waste banana blossom peel. The well-known characteristic phenomenon of surface Plasmon resonance (SPR) has been exploited towards the characterization of the green synthesized nanoparticles. The aforementioned nanoparticles were characterized by UV spectroscopy and the behaviour of these particles towards naked eye detection of metal ions were observed. The sensitivity of the nanoparticles towards the detection of metal ions was carefully monitored by the shift in the SPR band. Moreover the larvicidal potential of these green synthesized silver nanoparticles were evaluated as per WHO standards. The synthesized silver nanoparticles were found to be an effective antibacterial agent against Gram negative bacteria-E.coli. The method we followed for the synthesis of silver nanoparticles is economically feasible as well as environment friendly and also capable of rapid synthesis of nanoparticles at ambient conditions.

Human movement stochastic variability leads to diagnostic biomarkers In Autism Spectrum Disorders (ASD)

Science.gov (United States)

Wu, Di; Torres, Elizabeth B.; Jose, Jorge V.

2015-03-01

ASD is a spectrum of neurodevelopmental disorders. The high heterogeneity of the symptoms associated with the disorder impedes efficient diagnoses based on human observations. Recent advances with high-resolution MEM wearable sensors enable accurate movement measurements that may escape the naked eye. It calls for objective metrics to extract physiological relevant information from the rapidly accumulating data. In this talk we'll discuss the statistical analysis of movement data continuously collected with high-resolution sensors at 240Hz. We calculated statistical properties of speed fluctuations within the millisecond time range that closely correlate with the subjects' cognitive abilities. We computed the periodicity and synchronicity of the speed fluctuations' from their power spectrum and ensemble averaged two-point cross-correlation function. We built a two-parameter phase space from the temporal statistical analyses of the nearest neighbor fluctuations that provided a quantitative biomarker for ASD and adult normal subjects and further classified ASD severity. We also found age related developmental statistical signatures and potential ASD parental links in our movement dynamical studies. Our results may have direct clinical applications.

Phthalate pollution in an Amazonian rainforest.

Science.gov (United States)

Lenoir, Alain; Boulay, Raphaël; Dejean, Alain; Touchard, Axel; Cuvillier-Hot, Virginie

2016-08-01

Phthalates are ubiquitous contaminants and endocrine-disrupting chemicals that can become trapped in the cuticles of insects, including ants which were recognized as good bioindicators for such pollution. Because phthalates have been noted in developed countries and because they also have been found in the Arctic, a region isolated from direct anthropogenic influence, we hypothesized that they are widespread. So, we looked for their presence on the cuticle of ants gathered from isolated areas of the Amazonian rainforest and along an anthropogenic gradient of pollution (rainforest vs. road sides vs. cities in French Guiana). Phthalate pollution (mainly di(2-ethylhexyl) phthalate (DEHP)) was higher on ants gathered in cities and along road sides than on those collected in the pristine rainforest, indicating that it follows a human-mediated gradient of disturbance related to the use of plastics and many other products that contain phthalates in urban zones. Their presence varied with the ant species; the cuticle of Solenopsis saevissima traps higher amount of phthalates than that of compared species. However, the presence of phthalates in isolated areas of pristine rainforests suggests that they are associated both with atmospheric particles and in gaseous form and are transported over long distances by wind, resulting in a worldwide diffusion. These findings suggest that there is no such thing as a "pristine" zone.

Human phthiriasis. Can dermoscopy really help dermatologists? Entodermoscopy: a new dermatological discipline on the edge of entomology.

Science.gov (United States)

Scanni, G

2012-02-01

The diagnosis of human phtiriasis (often referred to as the "crab" or the "pubic louse") can be more difficult than other types of pediculosis (Pediculus corporis and Pediculus capitis) because this insect has a smaller body of 1.2 x 0.8 mm, may be lighter in color, not as mobile and therefore harder to see to the naked eye. Can dermoscopy aid to perform a better analysis of the skin? The clinical experience developed in two patients gives an affirmative answer, moreover adding useful information of insect and its eggs already known to entomologists but never used in dermatological diagnosis. The identification in vivo can distinguish Phthirus pubis from other skin signs while the conical shape of the operculum and the wide fixing sleeve of egg to hair, tells what species of louse is infesting, even if the insect is unavailable or nits are elsewhere from the pubic area. Entodermoscopy, provided that dermatologists have some knowledge of entomology, therefore promises advantages over standard microscopic examination.

Adaptive Scanning Optical Microscope (ASOM): A multidisciplinary optical microscope design for large field of view and high resolution imaging

NARCIS (Netherlands)

Potsaid, B.; Bellouard, Y.J.; Wen, J.T.

2005-01-01

From micro-assembly to biological observation, the optical microscope remains one of the most important tools for observing below the threshold of the naked human eye. However, in its conventional form, it suffers from a trade-off between resolution and field of view. This paper presents a new

Effects of egg shell quality and washing on Salmonella Infantis penetration.

Science.gov (United States)

Samiullah; Chousalkar, K K; Roberts, J R; Sexton, M; May, D; Kiermeier, A

2013-07-15

The vast majority of eggs in Australia are washed prior to packing to remove dirt and fecal material and to reduce the microbial contamination of the egg shell. The egg contents can be an ideal growth medium for microorganisms which can result in human illness if eggs are stored improperly and eaten raw or undercooked, and it is estimated that egg-related salmonellosis is costing Australia $44 million per year. Egg shell characteristics such as shell thickness, amount of cuticle present, and thickness of individual egg shell layers can affect the ease with which bacteria can penetrate the egg shell and washing could partially or completely remove the cuticle layer. The current study was conducted to investigate the effects of egg washing on cuticle cover and effects of egg shell quality and cuticle cover on Salmonella Infantis penetration of the egg shell. A higher incidence of unfavorable ultrastructural variables of the mammillary layer such as late fusion, type B bodies, type A bodies, poor cap quality, alignment, depression, erosion and cubics were recorded in Salmonella penetrated areas of egg shells. The influence of egg washing on the ability of Salmonella Infantis on the egg shell surface to enter the egg internal contents was also investigated using culture-based agar egg penetration and real-time qPCR based experiments. The results from the current study indicate that washing affected cuticle cover. There were no significant differences in Salmonella Infantis penetration of washed or unwashed eggs. Egg shell translucency may have effects on Salmonella Infantis penetration of the egg shell. The qPCR assay was more sensitive for detection of Salmonella Infantis from egg shell wash and internal contents than traditional microbiological methods. The agar egg and whole egg inoculation experiments indicated that Salmonella Infantis penetrated the egg shells. Egg washing not only can be highly effective at removing Salmonella Infantis from the egg shell surface

Removal of reproductive suppression reveals latent sex differences in brain steroid hormone receptors in naked mole-rats, Heterocephalus glaber.

Science.gov (United States)

Swift-Gallant, Ashlyn; Mo, Kaiguo; Peragine, Deane E; Monks, D Ashley; Holmes, Melissa M

2015-01-01

Naked mole-rats are eusocial mammals, living in large colonies with a single breeding female and 1-3 breeding males. Breeders are socially dominant, and only the breeders exhibit traditional sex differences in circulating gonadal steroid hormones and reproductive behaviors. Non-reproductive subordinates also fail to show sex differences in overall body size, external genital morphology, and non-reproductive behaviors. However, subordinates can transition to breeding status if removed from their colony and housed with an opposite-sex conspecific, suggesting the presence of latent sex differences. Here, we assessed the expression of steroid hormone receptor and aromatase messenger RNA (mRNA) in the brains of males and females as they transitioned in social and reproductive status. We compared in-colony subordinates to opposite-sex subordinate pairs that were removed from their colony for either 1 day, 1 week, 1 month, or until they became breeders (i.e., produced a litter). Diencephalic tissue was collected and mRNA of androgen receptor (Ar), estrogen receptor alpha (Esr1), progesterone receptor (Pgr), and aromatase (Cyp19a1) was measured using qPCR. Testosterone, 17β-estradiol, and progesterone from serum were also measured. As early as 1 week post-removal, males exhibited increased diencephalic Ar mRNA and circulating testosterone, whereas females had increased Cyp19a1 mRNA in the diencephalon. At 1 month post-removal, females exhibited increased 17β-estradiol and progesterone. The largest changes in steroid hormone receptors were observed in breeders. Breeding females had a threefold increase in Cyp19a1 and fivefold increases in Esr1 and Pgr, whereas breeding males had reduced Pgr and increased Ar. These data demonstrate that sex differences in circulating gonadal steroids and hypothalamic gene expression emerge weeks to months after subordinate animals are removed from reproductive suppression in their home colony.

Epicuticular wax on cherry laurel (Prunus laurocerasus) leaves does not constitute the cuticular transpiration barrier.

Science.gov (United States)

Zeisler, Viktoria; Schreiber, Lukas

2016-01-01

Epicuticular wax of cherry laurel does not contribute to the formation of the cuticular transpiration barrier, which must be established by intracuticular wax. Barrier properties of cuticles are established by cuticular wax deposited on the outer surface of the cuticle (epicuticular wax) and in the cutin polymer (intracuticular wax). It is still an open question to what extent epi- and/or intracuticular waxes contribute to the formation of the transpiration barrier. Epicuticular wax was mechanically removed from the surfaces of isolated cuticles and intact leaf disks of cherry laurel (Prunus laurocerasus L.) by stripping with different polymers (collodion, cellulose acetate and gum arabic). Scanning electron microscopy showed that two consecutive treatments with all three polymers were sufficient to completely remove epicuticular wax since wax platelets disappeared and cuticle surfaces appeared smooth. Waxes in consecutive polymer strips and wax remaining in the cuticle after treatment with the polymers were determined by gas chromatography. This confirmed that two treatments of the polymers were sufficient for selectively removing epicuticular wax. Water permeability of isolated cuticles and cuticles covering intact leaf disks was measured using (3)H-labelled water before and after selectively removing epicuticular wax. Cellulose acetate and its solvent acetone led to a significant increase of cuticular permeability, indicating that the organic solvent acetone affected the cuticular transpiration barrier. However, permeability did not change after two subsequent treatments with collodion and gum arabic or after treatment with the corresponding solvents (diethyl ether:ethanol or water). Thus, in the case of P. laurocerasus the epicuticular wax does not significantly contribute to the formation of the cuticular transpiration barrier, which evidently must be established by the intracuticular wax.

Some considerations about the quest for quantum gravity and a conjecture

International Nuclear Information System (INIS)

Matsas, George

2009-01-01

Full text. There are two main possible routes for the quest for quantum gravity; the top-down and the bottom-up ones. The first option is built on the hope that human endeavor and some luck will be enough to bring us over our goal, while the later one relies on our well tested physical theories to unveil reliable low-energy quantum gravity effects, which would eventually bridge us to the full theory. In this talk I shall argue in favor of the latter one and illustrate how this strategy can bring us new insights about some full quantum gravity problems. In particular, we will revisit in this context the problem of the existence of naked singularities and endorse the view that 'the cosmic censor' would be oblivious to processes involving quantum effects. Finally, inspired by our results, we raise a thought provoking conjecture connecting naked singularities to elementary particles, namely, that 'naked singularities and elementary particles would be low-energy manifestations of a same quantum gravity structure a nd argue that, if this is the case, the Higgs (scalar) boson expected to be found in the LHC would be a composite rather than an elementary particle. (author)

Immunohistochemical characterization of the chemosensory pulmonary neuroepithelial bodies in the naked mole-rat reveals a unique adaptive phenotype.

Directory of Open Access Journals (Sweden)

Jie Pan

Full Text Available The pulmonary neuroepithelial bodies (NEBs constitute polymodal airway chemosensors for monitoring and signaling ambient gas concentrations (pO2, pCO2/H+ via complex innervation to the brain stem controlling breathing. NEBs produce the bioactive amine, serotonin (5-HT, and a variety of peptides with multiple effects on lung physiology and other organ systems. NEBs in mammals appear prominent and numerous during fetal and neonatal periods, and decline in the post-natal period suggesting an important role during perinatal adaptation. The naked mole-rat (NMR, Heterocephalus glaber, has adapted to the extreme environmental conditions of living in subterranean burrows in large colonies (up to 300 colony mates. The crowded, unventilated burrows are environments of severe hypoxia and hypercapnia. However, NMRs adjust readily to above ground conditions. The chemosensory NEBs of this species were characterized and compared to those of the conventional Wistar rat (WR to identify similarities and differences that could explain the NMR's adaptability to environments. A multilabel immunohistochemical analysis combined with confocal microscopy revealed that the expression patterns of amine, peptide, neuroendocrine, innervation markers and chemosensor component proteins in NEBs of NMR were similar to that of WR. However, we found the following differences: 1 NEBs in both neonatal and adult NMR lungs were significantly larger and more numerous as compared to WR; 2 NEBs in NMR had a more variable compact cell organization and exhibited significant differences in the expression of adhesion proteins; 3 NMR NEBs showed a significantly greater ratio of 5-HT positive cells with an abundance of 5-HT; 4 NEBs in NMR expressed the proliferating cell nuclear antigen (PCNA and the neurogenic gene (MASH1 indicating active proliferation and a state of persistent differentiation. Taken together our findings suggest that NEBs in lungs of NMR are in a hyperactive, functional

Two new species of the genus Streptomyces: Streptomyces camponoti sp. nov. and Streptomyces cuticulae sp. nov. isolated from the cuticle of Camponotus japonicus Mayr.

Science.gov (United States)

Piao, Chenyu; Zheng, Weiwei; Li, Yao; Liu, Chongxi; Jin, Liying; Song, Wei; Yan, Kai; Wang, Xiangjing; Xiang, Wensheng

2017-09-01

Two novel actinomycetes, designated strains 2C-SSA16(2) T and 1C-GS8 T , were isolated from the cuticle of Camponotus japonicus Mayr, collected from Northeast Agricultural University, Heilongjiang Province, north China. Both of them contained genes (involved in antibiotics biosynthesis) of the ketosynthase (KS) and methyl malonyl transferase domains (PKS-I) and the adenylation domain (NRPS). A polyphasic study was carried out to establish the taxonomic positions of these strains. The 16S rRNA gene sequence analysis showed that the two novel isolates 2C-SSA16(2) T and 1C-GS8 T exhibited 98.8% similarity with each other and that they are most closely related to Streptomyces umbrinus JCM 4521 T (99.0, 98.6%), Streptomyces ederensis JCM 4958 T (98.9, 98.7%), Streptomyces aurantiacus JCM 4453 T (98.6, 98.2%), Streptomyces glomeroaurantiacus JCM 4677 T (98.6, 98.1%), Streptomyces tauricus JCM4837 T (98.2, 98.0%) and Streptomyces phaeochromogenes JCM 4070 T (98.2, 99.2%). The corresponding phylogenetic analysis based on partial gyrB gene sequences showed that strains 2C-SSA16(2) T and 1C-GS8 T formed a cluster with the above-mentioned strains. The DNA-DNA hybridization data and phenotypic characteristics indicated that strains 2C-SSA16(2) T and 1C-GS8 T could be readily distinguished from each other and their closest phylogenetic relatives. Therefore, these two strains are suggested to represent two novel species of the genus Streptomyces, for which the names Streptomyces camponoti sp. nov. and Streptomyces cuticulae sp. nov. are proposed. The type strains are 2C-SSA16(2) T (=CGMCC 4.7276 T  = DSM 100522 T ) and 1C-GS8 T (=CGMCC 4.7348 = DSM 103127 T ), respectively.

[Effect of M007 mediated photodynamic therapy on proliferation of human osteosarcoma MG63 cells in vitro].

Science.gov (United States)

Zhou, Yu-Kai; Wu, Wen-Zhi; Zhang, Lan; Yang, Chun-Hui; Wang, Yan-Ping

2012-01-01

To investigate the effect of a new photosensitizer, M007 mediated photodynamic therapy on proliferation of human osteosarcoma MG63 cells in vitro. Human osteosarcoma MG63 cells were prepared as 1 x 10(6) /mL single-cell suspension, and 1 mL cells were transferred into 60 mL culture dish, then treated with 5 different gradient dosages (0, 2, 4, 8, 16 micromol/L) of M007 followed by photodynamic therapy or dark reaction for 10 min. The survival rate of the cells and the mode of cell death were detected by flow cytometry with the stain of Annexin V-FITC/PI. The effect on proliferation of survival cells was observed by MTT assay and colony-forming assay. M007 mediated photodynamic therapy induced the inactivation of MG63 human osteosarcoma cells in the way of late apoptosis/necrosis or becoming naked nucleus predominately. More than 90% MG63 cells in M007-PDT group were dead under the treatment of 2-16 micromol/L M007. The survival rates of 4-16 micromol/L M007-PDT group were steadily less than 1%. The optical densities did not increase with extension of culture time in 2-8 micromol/L M007-PDT group (P > 0.05). There were 16 survival alive cells found occasionally in 2 micromol/L M007-PDT group, but no colonies found in other groups. M007 mediated photodynamic therapy totally inactivated human osteosarcoma MG63 cells in vitro with the dosage more than 4 micromol/L.

The northern naked-tailed armadillo in the Lacandona rainforest, Mexico: new records and potential threats Armadillo de cola desnuda en la selva lacandona, México: nuevos registros y amenazas potenciales

Directory of Open Access Journals (Sweden)

Arturo González-Zamora

2012-06-01

Full Text Available We review historic occurrences in Mexico of one of the least known Xenarthra of Mesoamerica - the northern naked-tailed armadillo (Cabassous centralis Miller, 1899. We document 6 new records in the Lacandona rainforest, southern Mexico, and through interviews with local people, we assess potential threats for this species in the region. In addition to being locally rare, our results show that hunting and death by road-kill may be major threats to this species in the region.Se revisaron los registros históricos en México de uno de los xenartros menos conocidos de Mesoamérica - el armadillo de cola desnuda (Cabassous centralis Miller, 1899. Se documentan 6 nuevos registros en la selva lacandona, sur de México. A través de entrevistas con pobladores locales, se evaluaron las amenazas potenciales para esta especie en la región. Además de ser localmente rara, nuestros resultados muestran que la cacería y las muertes por atropellamiento pueden ser las principales amenazas para esta especie en la región.

A chitinase with two catalytic domains is required for organization of the cuticular extracellular matrix of a beetle.

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Mi Young Noh

2018-03-01

Full Text Available Insect cuticle or exoskeleton is an extracellular matrix formed primarily from two different structural biopolymers, chitin and protein. During each molt cycle, a new cuticle is deposited simultaneously with degradation of the inner part of the chitinous procuticle of the overlying old exoskeleton by molting fluid enzymes including epidermal chitinases. In this study we report a novel role for an epidermal endochitinase containing two catalytic domains, TcCHT7, from the red flour beetle, Tribolium castaneum, in organizing chitin in the newly forming cuticle rather than in degrading chitin present in the prior one. Recombinant TcCHT7 expressed in insect cells is membrane-bound and capable of hydrolyzing an extracellular chitin substrate, whereas in vivo, this enzyme is also released from the plasma membrane and co-localizes with chitin in the entire procuticle. RNAi of TcCHT7 reveals that this enzyme is nonessential for any type of molt or degradation of the chitinous matrix in the old cuticle. In contrast, TcCHT7 is required for maintaining the integrity of the cuticle as a compact structure of alternating electron-dense and electron-lucent laminae. There is a reduction in thickness of elytral and leg cuticles after RNAi for TcCHT7. TcCHT7 is also required for formation of properly oriented long chitin fibers inside pore canals that are vertically oriented columnar structures, which contribute to the mechanical strength of a light-weight, yet rigid, adult cuticle. The conservation of CHT7-like proteins harboring such a unique domain configuration among many insect and other arthropod species indicates a critical role for the group III class of chitinases in the higher ordered organization of chitin fibers for development of the structural integrity of many invertebrate exoskeletons.

The MrCYP52 cytochrome P450 monoxygenase gene of Metarhizium robertsii is important for utilizing insect epicuticular hydrocarbons.

Directory of Open Access Journals (Sweden)

Liangcai Lin

Full Text Available Fungal pathogens of plants and insects infect their hosts by direct penetration of the cuticle. Plant and insect cuticles are covered by a hydrocarbon-rich waxy outer layer that represents the first barrier against infection. However, the fungal genes that underlie insect waxy layer degradation have received little attention. Here we characterize the single cytochrome P450 monoxygenase family 52 (MrCYP52 gene of the insect pathogen Metarhizium robertsii, and demonstrate that it encodes an enzyme required for efficient utilization of host hydrocarbons. Expressing a green florescent protein gene under control of the MrCYP52 promoter confirmed that MrCYP52 is up regulated on insect cuticle as well as by artificial media containing decane (C10, extracted cuticle hydrocarbons, and to a lesser extent long chain alkanes. Disrupting MrCYP52 resulted in reduced growth on epicuticular hydrocarbons and delayed developmental processes on insect cuticle, including germination and production of appressoria (infection structures. Extraction of alkanes from cuticle prevented induction of MrCYP52 and reduced growth. Insect bioassays against caterpillars (Galleria mellonella confirmed that disruption of MrCYP52 significantly reduces virulence. However, MrCYP52 was dispensable for normal germination and appressorial formation in vitro when the fungus was supplied with nitrogenous nutrients. We conclude therefore that MrCYP52 mediates degradation of epicuticular hydrocarbons and these are an important nutrient source, but not a source of chemical signals that trigger infection processes.

Characterization of an entomopathogenic fungi target integument protein, Bombyx mori single domain von Willebrand factor type C, in the silkworm, Bombyx mori.

Science.gov (United States)

Han, F; Lu, A; Yuan, Y; Huang, W; Beerntsen, B T; Huang, J; Ling, E

2017-06-01

The insect cuticle works as the first line of defence to protect insects from pathogenic infections and water evaporation. However, the old cuticle must be shed in order to enter the next developmental stage. During each ecdysis, moulting fluids are produced and secreted into the area among the old and new cuticles. In a previous study, the protein Bombyx mori single domain von Willebrand factor type C (BmSVWC; BGIBMGA011399) was identified in the moulting fluids of Bo. mori and demonstrated to regulate ecdysis. In this study we show that in Bo. mori larvae, BmSVWC primarily locates to the integument (epidermal cells and cuticle), wing discs and head. During the moulting stage, BmSVWC is released into the moulting fluids, and is then produced again by epidermal cells after ecdysis. Fungal infection was shown to decrease the amount of BmSVWC in the cuticle, which indicates that BmSVWC is a target protein of entomopathogenic fungi. Thus, BmSVWC is mainly involved in maintaining the integrity of the integument structure, which serves to protect insects from physical damage and pathogenic infection. © 2017 The Royal Entomological Society.

Socially regulated reproductive development: analysis of GnRH-1 and kisspeptin neuronal systems in cooperatively breeding naked mole-rats (Heterocephalus glaber).

Science.gov (United States)

Zhou, Shuzhi; Holmes, Melissa M; Forger, Nancy G; Goldman, Bruce D; Lovern, Matthew B; Caraty, Alain; Kalló, Imre; Faulkes, Christopher G; Coen, Clive W

2013-09-01

In naked mole-rat (NMR) colonies, breeding is monopolized by the queen and her consorts. Subordinates experience gonadal development if separated from the queen. To elucidate the neuroendocrine factors underlying reproductive suppression/development in NMRs, we quantified plasma gonadal steroids and GnRH-1- and kisspeptin-immunoreactive (ir) neurons in subordinate adults and in those allowed to develop into breeders, with or without subsequent gonadectomy. In males and females, respectively, plasma testosterone and progesterone are higher in breeders than in subordinates. No such distinction occurs for plasma estradiol; its presence after gonadectomy and its positive correlation with adrenal estradiol suggest an adrenal source. Numbers of GnRH-1-ir cell bodies do not differ between gonad-intact breeders and subordinates within or between the sexes. As in phylogenetically related guinea pigs, kisspeptin-ir processes pervade the internal and external zones of the median eminence. Their distribution is consistent with actions on GnRH-1 neurons at perikaryal and/or terminal levels. In previously investigated species, numbers of kisspeptin-ir cell bodies vary from substantial to negligible according to sex and/or reproductive state. NMRs are exceptional: irrespective of sex, reproductive state, or presence of gonads, substantial numbers of kisspeptin-ir cell bodies are detected in the rostral periventricular region of the third ventricle (RP3V) and in the anterior periventricular (PVa), arcuate, and dorsomedial hypothalamic nuclei. Nevertheless, the greater number in the RP3V/PVa of female breeders compared with female subordinates or male breeders suggests that emergence from a hypogonadotrophic state in females may involve kisspeptin-related mechanisms similar to those underlying puberty or seasonal breeding in other species. Copyright © 2013 Wiley Periodicals, Inc.

Comparative ultrastructure of the root system in rhizocephalan barnacles (Crustacea

DEFF Research Database (Denmark)

Bresciani, J; Høeg, Jens Thorvald

2001-01-01

. The rootlets consist of a cuticle, an epidermis and a subjacent layer of axial cells that often, but not always surround, a central lumen. The rootlets are at all times enclosed in a less than 0.5 microm thick cuticle, which is never molted. The cuticle consists of an inner homogeneous layer with a slightly...... by long septate junctions and exhibit the characteristics of a transporting epithelium. Experiments with acid phosphatase revealed activity both in the epidermis and among the microcuticular projections. The projections may therefore form a domain that is important in absorption and extracellular...... the rootlets towards the external reproductive body. In C. delagei the single, bladder-shaped rootlet lacks both the apical projections in the epidermis, the electron-dense cuticle layer, and the microcuticular projections. We review previous studies on the rhizocephalan root system and discuss functional...

Alterações na cutícula de maçãs ‘Fuji’ e ‘Gala’ em função do tratamento térmico e da armazenagem refrigerada = Changes on ‘Fuji’ and ‘Gala’ apple cuticle as a result of heat treatment and cold storage

Directory of Open Access Journals (Sweden)

Cândida Raquel Scherrer Montero

2010-07-01

Full Text Available As doenças de pós-colheita são fatores limitantes para estocagem de produtos colhidos. É crescente o interesse por métodos alternativos para o controle de podridão em póscolheita. A termoterapia pré-estocagem parece ser um método promissor podendo ser aliado aoutros métodos alternativos. O objetivo deste trabalho foi verificar os efeitos do tratamento térmico por aspersão e imersão na cutícula de maçãs (Malus domestica Borkh. Fuji e Gala após tratamento e período curto de armazenagem. Foram realizados seis tratamentos, com três repetições de três frutos: testemunha, imersão em água quente a 58ºC-30 s, 1 e 2 min., aspersão em água quente a 58ºC-30 s; imersão em clorofórmio 30 segundos. Foram retiradas amostras para visualização em microscopia eletrônica de varredura na instalação e três semanas de armazenamento a 0ºC. Durante a armazenagem, as rachaduras da cutícula aumentam em largura, sendo esta uma característica importante na pós-colheita, pois estas propiciam maior perda de água e podem tornar-se sítios de penetração de patógenos. O calor derrete os cristaloides de cera da cutícula para formar um padrão de recobrimento mais homogêneo na superfície e a oclusão defraturas, podendo atuar como barreira física para evitar a entrada de patógenos nas maçãs bem como reduzir a perda de massa fresca.Postharvest diseases are limiting factors to the storage of many crops. There is a growing interest in alternative methods to control postharvest diseases. Pre-storage heat treatment seems to be one of the most promising rot control methods, associated with other alternative methods. The objective of this work was to verify the effects of immersion and spraying heat treatment on the cuticle of Fuji and Gala apples (Malus domestica Borkh. right after treatment and a short storage period. This experiment consisted of six treatments, three replications of three fruits each: no treatment; hot water

Humanization of JAA-F11, a Highly Specific Anti-Thomsen-Friedenreich Pancarcinoma Antibody and In Vitro Efficacy Analysis

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Swetha Tati

2017-09-01

Full Text Available JAA-F11 is a highly specific mouse monoclonal to the Thomsen-Friedenreich Antigen (TF-Ag which is an alpha-O-linked disaccharide antigen on the surface of ~80% of human carcinomas, including breast, lung, colon, bladder, ovarian, and prostate cancers, and is cryptic on normal cells. JAA-F11 has potential, when humanized, for cancer immunotherapy for multiple cancer types. Humanization of JAA-F11, was performed utilizing complementarity determining regions grafting on a homology framework. The objective herein is to test the specificity, affinity and biology efficacy of the humanized JAA-F11 (hJAA-F11. Using a 609 target glycan array, 2 hJAA-F11 constructs were shown to have excellent chemical specificity, binding only to TF-Ag alpha-linked structures and not to TF-Ag beta-linked structures. The relative affinity of these hJAA-F11 constructs for TF-Ag was improved over the mouse antibody, while T20 scoring predicted low clinical immunogenicity. The hJAA-F11 constructs produced antibody-dependent cellular cytotoxicity in breast and lung tumor lines shown to express TF-Ag by flow cytometry. Internalization of hJAA-F11 into cancer cells was also shown using a surface binding ELISA and confirmed by immunofluorescence microscopy. Both the naked hJAA-F11 and a maytansine-conjugated antibody (hJAA-F11-DM1 suppressed in vivo tumor progression in a human breast cancer xenograft model in SCID mice. Together, our results support the conclusion that the humanized antibody to the TF-Ag has potential as an adjunct therapy, either directly or as part of an antibody drug conjugate, to treat breast cancer, including triple negative breast cancer which currently has no targeted therapy, as well as lung cancer.

Hydrodynamic gene delivery in human skin using a hollow microneedle device.

Science.gov (United States)

Dul, M; Stefanidou, M; Porta, P; Serve, J; O'Mahony, C; Malissen, B; Henri, S; Levin, Y; Kochba, E; Wong, F S; Dayan, C; Coulman, S A; Birchall, J C

2017-11-10

Microneedle devices have been proposed as a minimally invasive delivery system for the intradermal administration of nucleic acids, both plasmid DNA (pDNA) and siRNA, to treat localised disease or provide vaccination. Different microneedle types and application methods have been investigated in the laboratory, but limited and irreproducible levels of gene expression have proven to be significant challenges to pre-clinical to clinical progression. This study is the first to explore the potential of a hollow microneedle device for the delivery and subsequent expression of pDNA in human skin. The regulatory approved MicronJet600® (MicronJet hereafter) device was used to deliver reporter plasmids (pCMVβ and pEGFP-N1) into viable excised human skin. Exogenous gene expression was subsequently detected at multiple locations that were distant from the injection site but within the confines of the bleb created by the intradermal bolus. The observed levels of gene expression in the tissue are at least comparable to that achieved by the most invasive microneedle application methods e.g. lateral application of a microneedle. Gene expression was predominantly located in the epidermis, although also evident in the papillary dermis. Optical coherence tomography permitted real time visualisation of the sub-surface skin architecture and, unlike a conventional intradermal injection, MicronJet administration of a 50μL bolus appears to create multiple superficial microdisruptions in the papillary dermis and epidermis. These were co-localised with expression of the pCMVβ reporter plasmid. We have therefore shown, for the first time, that a hollow microneedle device can facilitate efficient and reproducible gene expression of exogenous naked pDNA in human skin using volumes that are considered to be standard for intradermal administration, and postulate a hydrodynamic effect as the mechanism of gene delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

Pragmatics in language change and lexical creativity.

Science.gov (United States)

Allan, Keith

2016-01-01

This essay examines language change and linguistic creativity as revealed by remodelling, especially as a source for euphemisms and euphemistic dysphemisms and as a function of verbal play. Within the scope of this essay, there are predominantly two ways in which novel terms and expressions are created leading to language change: formally through remodelling and semantically through figurative language. Consider some of the words for nakedness. There is the orthophemistic term nude, from Latin nudus, often used of photographic or painted representations of naked women and, much more rarely, of a naked man-hence the marked term male nude. Whether a nude is artistic or pornographic depends on the viewer belief. A colloquial Australian euphemism for being in the nude is in the nuddie. Other euphemisms include as nature intended, in one's birthday suit, in the altogether, and in the buff (⇐buff[alo] leather, buff skin transferred to humans). Being naked is captured by the dysphemism bare-arsed and the more euphemistic butt / buck naked in which buck ⇐ butt. The orthophemistic term stark naked and the connected colloquial euphemism starkers also arose by replacing a final /t/ with a /k/: stark ⇐ start "tail, arse". Nudists like to go about in the open air without clothes on and, being as nature intended when in natural surroundings, are euphemistically called naturists. Such expressions display folk-culture in a remarkable inventiveness of metaphor and figurative language sourced in the perceived characteristics of whatever is being talked about. For instance, terms for tabooed objects and events provide ready-made material for the dysphemistic language of curses, insults, epithets, and expletives. The essay shows that X-phemisms (orthophemisms and/or euphemisms and/or dysphemisms) are motivated by a speaker/writer's want to be seen to take a certain stance by upgrading, downgrading, obfuscating, and deceiving; and they extensively manifest indulgence in

Microscopic identification of the remnant hair or feather of five animal drug components in Shenrongbian pill

Directory of Open Access Journals (Sweden)

Tingguo Kang

2012-06-01

Full Text Available A comparative study was performed to identify the microscopic characteristics of hair or feather in the five animal drug components contained in Shenrongbian pill. Penis et Testis Canis is 40±0.07 in the medulla index, with long circular, banana or triangular circular shaped medulla cells arranged in one line or network, and the hair cuticle is in imbrication (d, m and flat wave (p shape. Penis et Testis Equi is 66±0.10 in the medulla index, with ellipse, spindle or long strip-shaped medulla cells arranged in network, and the hair cuticle is in flat wave shape. Penis et Testis Bovis is 67±0.05 in the medulla index, with rectangle, spindle or polygon-shaped medulla cells arranged in ladder or network form, and the hair cuticle is in flat wave shape. Penis et Testis Mustelae is 29±0.05 in the medulla index, with ellipse-like, square-like or circular shaped medulla cells arranged in one line generally, and the hair cuticle is in acuminate (d, m, imbrication (m,p and slightly flat wave (p shape. Musculus et Bonis Passeris is 24±0.05 in the medulla index, with bamboo joint-shaped barbs and unclear medulla cells, without hair cuticle.

Aspects of cuticular sclerotization in the locust, Scistocerca gregaria, and the beetle, Tenebrio molitor.

Science.gov (United States)

Andersen, Svend Olav; Roepstorff, Peter

2007-03-01

The number of reactive amino groups in cuticular proteins decreases during the early period of insect cuticular sclerotization, presumably due to reaction with oxidation products of N-acetyldopamine (NADA) and N-beta-alanyldopamine (NBAD). We have quantitated the decrease in cuticular N-terminal amino groups and lysine epsilon-amino groups during the first 24h of sclerotization in adult locusts, Schistocerca gregaria, and in larval and adult beetles, Tenebrio molitor, as well as the increase in beta-alanine amino groups in Tenebrio cuticle. The results indicate that nearly all glycine N-terminal groups and a significant part of the epsilon-amino groups from lysine residues are involved in the sclerotization process in both locusts and Tenebrio. A pronounced increase in the amount of free beta-alanine amino groups was observed in cuticle from adult Tenebrio and to a lesser extent also in Tenebrio larval cuticle, but from locust cuticle no beta-alanine was obtained. Hydrolysis of sclerotized cuticles from locusts and Tenebrio by dilute hydrochloric acid released a large number of compounds containing amino acids linked to catecholic moieties. Products have been identified which contain histidine residues linked via their imidazole group to the beta-position of various catechols, such as dopamine, 3,4-dihydroxyphenyl-ethanol (DOPET), and 3,4-dihydroxyphenyl-acetaldehyde (DOPALD), and a ketocatecholic compound has also been identified composed of lysine linked via its epsilon-amino group to the alpha-carbon atom of 3,4-dihydroxyacetophenone. Some of the hydrolysis products have previously been obtained from sclerotized pupal cuticle of Manduca sexta [Xu, R., Huang, X., Hopkins, T.L., Kramer, K.J., 1997. Catecholamine and histidyl protein cross-linked structures in sclerotized insect cuticle. Insect Biochemistry and Molecular Biology 27, 101-108; Kerwin, J.L., Turecek, F., Xu, R., Kramer, K.J., Hopkins, T.L., Gatlin, C.L., Yates, J.R., 1999. Mass spectrometric analysis

The injury and cumulative effects on human skin by UV exposure from artificial fluorescence emission.

Science.gov (United States)

Tian, Yan; Liu, Wei; Niu, TianHui; Dai, CaiHong; Li, Xiaoxin; Cui, Caijuan; Zhao, Xinyan; E, Yaping; Lu, Hui

2014-01-01

The injury and cumulative effects of UV emission from fluorescence lamp were studied. UV intensity from fluorescence lamp was measured, and human skin samples (hips, 10 volunteers) were exposed to low-dose UV irradiation (three times per week for 13 consecutive weeks). Three groups were examined: control group without UV radiation; low-dose group with a cumulative dose of 50 J cm(-2) which was equivalent to irradiation of the face during indoor work for 1.5 years; and high-dose group with 1000 J cm(-2) cumulative dose equivalent to irradiation of the face during outdoor activities for 1 year. Specific indicators were measured before and after UVA irradiation. The findings showed that extending the low-dose UVA exposure decreased the skin moisture content and increased the transepidermal water loss as well as induced skin color changes (decreased L* value, increased M index). Furthermore, irradiated skin showed an increased thickness of cuticle and epidermis, skin edema, light color and unclear staining collagen fibers in the dermis, and elastic fiber fragmentation. In addition, MMP-1, p53 and SIRT1 expression was also increased. Long-term exposure of low-dose UVA radiation enhanced skin photoaging. The safety of the fluorescent lamp needs our attention. © 2014 The American Society of Photobiology.

Simulation of the ozone pretreatment of wheat straw.

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Bhattarai, Sujala; Bottenus, Danny; Ivory, Cornelius F; Gao, Allan Haiming; Bule, Mahesh; Garcia-Perez, Manuel; Chen, Shulin

2015-11-01

Wheat straw is a potential feedstock in biorefinery for sugar production. However, the cellulose, which is the major source of sugar, is protected by lignin. Ozonolysis deconstructs the lignin and makes cellulose accessible to enzymatic digestion. In this study, the change in lignin concentration with different ozonolysis times (0, 1, 2, 3, 5, 7, 10, 15, 20, 30, 60min) was fit to two different kinetic models: one using the model developed by Garcia-Cubero et al. (2012) and another including an outer mass transfer barrier or "cuticle" region where ozone mass transport is reduced in proportion to the mass of unreacted insoluble lignin in the cuticle. The kinetic parameters of two mathematical models for predicting the soluble and insoluble lignin at different pretreatment time were determined. The results showed that parameters derived from the cuticle-based model provided a better fit to experimental results compared to a model without a cuticle layer. Copyright © 2015 Elsevier Ltd. All rights reserved.

SEM study of Anisakis brevispiculata Dollfus, 1966 and Pseudoterranova ceticola (Deardoff and Overstreet, 1981 (Nematoda: Anisakidae, parasites of the pygmy sperm whale Kogia breviceps

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Elvira Abollo

2002-09-01

Full Text Available Scanning Electron Microscopy (SEM was used to study different topo-morphological characteristics of the architecture (cuticle, excretory pore, lips and adjacent structures, number and distribution patterns of caudal papillae and papillae-like structures of the anisakid nematodes Anisakis brevispiculata and Pseudoterranova ceticola, parasites in the stomach of the pygmy sperm whale Kogia breviceps. SEM micrographs herein help to accurately define the above surface topographical features by adding a more adequate 3-D picture to the original descriptions of both parasitic species. In A. brevispiculata the entire body cuticle structure, well-differentiated paracloacal papillae and the wrinkle cuticle of the papillae are clear examples that enhance the above differentiation of structures as seen by LM or SEM. Similarly, in P. ceticola the cuticle striations, bulky cloacal lips, rectangular distribution pattern of distal papillae and the absence of a groove separating paracloacal papillae which are obliquely arranged are all different to those features previously described.

Cuticular characteristics in the detection of plant stress due to air pollution - new problems in the use of these cuticular characteristics

International Nuclear Information System (INIS)

Garrec, J.P.

1994-01-01

The foliar surface, and particularly the cuticle, is the first zone of impact of air pollutants on leaves. At the level of the cuticle, it is mainly studies on the modifications of the physico-chemical properties of the waxes that allow us to detect and estimate plant stress. However, during recent years, with modifications in the nature and level of air pollution (decrease of primary pollutants: SO 2 , HF; increase of secondary pollutants: O 2 , acid deposits; increase of nitrogen deposits; increase of organic micropollutants; appearence of global environmental problems: CO 2 , climatic change), the physiological impact on plants and in particular on the cuticle is different. For this reason, new problems have appeared and use of cuticular characteristics in the detection of plant stress due to air pollutants has recently evolved. Some examples are given, but much remains to be done to understand the effects on the cuticle of these new modifications of the atmospheric environment of plants. (orig.)

Plasmonic gold nanoparticles for detection of fungi and human cutaneous fungal infections.

Science.gov (United States)

Sojinrin, Tobiloba; Conde, João; Liu, Kangze; Curtin, James; Byrne, Hugh J; Cui, Daxiang; Tian, Furong

2017-07-01

Fungi, which are common in the environment, can cause a multitude of diseases. Warm, humid conditions allow fungi to grow and infect humans via the respiratory, digestive and reproductive tracts, genital area and other bodily interfaces. Fungi can be detected directly by microscopy, using the potassium hydroxide test, which is the gold standard and most popular method for fungal screening. However, this test requires trained personnel operating specialist equipment, including a fluorescent microscope and culture facilities. As most acutely infected patients seek medical attention within the first few days of symptoms, the optimal diagnostic test would be rapid and self-diagnostic simplifying and improving the therapeutic outcome. In suspensions of gold nanoparticles, Aspergillus niger can cause a colour change from red to blue within 2 min, as a result of changes in nanoparticle shape. A similar colour change was observed in the supernatant of samples of human toenails dispersed in water. Scanning electron microscopy, UV/Vis and Raman spectroscopy were employed to monitor the changes in morphology and surface plasmon resonance of the nanoparticles. The correlation of colour change with the fungal infection was analysed using the absorbance ratio at 520 nm/620 nm. We found a decrease in the ratio when the fungi concentration increased from 1 to 16 CFU/mL, with a detection limit of 10 CFU/mL. The test had an 80% sensitivity and a 95% specificity value for the diagnosis of athlete's foot in human patients. This plasmonic gold nanoparticle-based system for detection of fungal infections measures the change in shape of gold nanoparticles and generates coloured solutions with distinct tonality. Our application has the potential to contribute to self-diagnosis and hygiene control in laboratories/hospitals with fewer resources, just using the naked eye. Graphical abstract Colorimetric method for fungi detection with gold nano particles.

The Naked Blunder

CERN Multimedia

Computer Security Team

2013-01-01

In the past, we have published many different articles on a multitude of aspects of computer security and on the risk to CERN and to you when you use your computer at CERN or at home. Some were relevant to all of us, others only to a minority. This time, we would like to raise a rather delicate and fortunately rare issue: the consultation of pornographic websites and why it is forbidden at CERN.   With 10,000 people at CERN of different cultural and professional backgrounds, some working outside traditional working hours and some staying in one of the three CERN hostels, it is a natural fact that behaviours, interests, perceptions and attitudes vary significantly. CERN highly values the diversity of its personnel and users and the interaction between them. In this respect, the CERN campus is comparable to a small city and, as in every small city, some citizens are attracted to pornography. It is not easy to find a common definition of pornography. It depends on our cultural roots, our value...

The naked experts

International Nuclear Information System (INIS)

Martin, B.

1982-01-01

In an article critical of experts, the cases argued for and against nuclear power are discussed under the headings: environmental hazards arising from the nuclear fuel cycle; proliferation of nuclear weapons capabilities via expansion of the nuclear power industry; political and social threats and restraints of a nuclear society (terrorism, reduction in civil liberties, centralised political and economic power); economic and employment disadvantages of nuclear power; impact of uranium mining on (Australian) aboriginal culture; inadequacy of nuclear power as a solution to energy problems; advantages of a 'soft energy path' based around conservation and renewable energy technologies. (U.K.)

The Naked Manager

DEFF Research Database (Denmark)

Meier Sørensen, Bent; Villadsen, Kaspar

2015-01-01

expressive and ‘liberated’ bodily comportment—is used tactically to shape the space of conduct of others in the company. The study foregrounds the managerial body as ‘signifier’ in its own right. Empirically, this is done through an analysis of video material produced by the film company Zentropa about...

Naked black holes

International Nuclear Information System (INIS)

Horowitz, G.T.; Ross, S.F.

1997-01-01

It is shown that there are large static black holes for which all curvature invariants are small near the event horizon, yet any object which falls in experiences enormous tidal forces outside the horizon. These black holes are charged and near extremality, and exist in a wide class of theories including string theory. The implications for cosmic censorship and the black hole information puzzle are discussed. copyright 1997 The American Physical Society

Evaluation of Egg Quality Traits of Local Chickens in the Humid ...

African Journals Online (AJOL)

Four hundred and thirty six (436) eggs laid by seven genotypes of local chickens within 56 days were used to evaluate egg quality traits. The genotypes evaluated were the homozygous naked neck (Na/Na) and frizzle (F/F), heterozygous naked neck (Na/na) and frizzle (F/na), reciprocal crosses between naked neck and ...

Knickkopf protein protects and organizes chitin in the newly synthesized insect exoskeleton

Science.gov (United States)

New cuticle synthesis and molting are complex developmental processes that all insects must undergo to allow for growth. However, little is known about how insects regulate the selective degradation of the old cuticle while leaving the new one intact. In this study we show that in the red flour beet...

Concurrent protein synthesis is required for in vivo chitin synthesis in postmolt blue crabs

International Nuclear Information System (INIS)

Horst, M.N.

1990-01-01

Chitin synthesis in crustaceans involves the deposition of a protein-polysaccharide complex at the apical surface of epithelial cells which secrete the cuticle or exoskeleton. The present study involves an examination of in vivo incorporation of radiolabeled amino acids and amino sugars into the cuticle of postmolt blue crabs, Callinectes sapidus. Rates of incorporation of both 3H leucine and 3H threonine were linear with respect to time of incubation. Incorporation of 3H threonine into the endocuticle was inhibited greater than 90% in the presence of the protein synthesis inhibitor, puromycin. Linear incorporation of 14C glucosamine into the cuticle was also demonstrated; a significant improvement of radiolabeling was achieved by using 14C-N-acetylglucosamine as the labeled precursor. Incorporation of 3H-N-acetylglucosamine into the cuticle of postmolt blue crabs was inhibited 89% by puromycin, indicating that concurrent protein synthesis is required for the deposition of chitin in the blue crab. Autoradiographic analysis of control vs. puromycin-treated crabs indicates that puromycin totally blocks labeling of the new endocuticle with 3H glucosamine. These results are consistent with the notion that crustacean chitin is synthesized as a protein-polysaccharide complex. Analysis of the postmolt and intermolt blue crab cuticle indicates that the exoskeleton contains about 60% protein and 40% chitin. The predominant amino acids are arginine, glutamic acid, alanine, aspartic acid, and threonine

H2O2 treatment or serum deprivation induces autophagy and apoptosis in naked mole-rat skin fibroblasts by inhibiting the PI3K/Akt signaling pathway.

Science.gov (United States)

Zhao, Shanmin; Li, Li; Wang, Shiyong; Yu, Chenlin; Xiao, Bang; Lin, Lifang; Cong, Wei; Cheng, Jishuai; Yang, Wenjing; Sun, Wei; Cui, Shufang

2016-12-20

Naked mole-rats (NMR; Heterocephalus glaber) display extreme longevity and resistance to cancer. Here, we examined whether autophagy contributes to the longevity of NMRs by assessing the effects of the PI3K/Akt pathway inhibitor LY294002 and the autophagy inhibitor chloroquine (CQ) on autophagy and apoptosis in NMR skin fibroblasts. Serum starvation, H2O2 treatment, and LY294002 treatment all increased the LC3-II/LC3-I ratio and numbers of double-membraned autophagosomes and autophagic vacuoles, and decreased levels of p70S6K, p-AktSer473, and p-AktThr308. By contrast, CQ treatment decreased p70S6K, AktSer473, and AktThr308 levels. The Bax/Bcl-2 ratio increased after 12 h of exposure to LY294002 or CQ. These data show that inhibiting the Akt pathway promotes autophagy and apoptosis in NMR skin fibroblasts. Furthermore, LY294002 or CQ treatment decreased caspase-3, p53, and HIF1-α levels, suggesting that serum starvation or H2O2 treatment increase autophagy and apoptosis in NMR skin fibroblasts by inhibiting the PI3K/Akt pathway. CQ-induced inhibition of late autophagy stages also prevented Akt activation and induced apoptosis. Finally, the HIF-1α and p53 pathways were involved in serum starvation- or H2O2-induced autophagy in NMR skin fibroblasts.

Persistent Dystrophin Protein Restoration 90 Days after a Course of Intraperitoneally Administered Naked 2′OMePS AON and ZM2 NP-AON Complexes in mdx Mice

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Elena Bassi

2012-01-01

Full Text Available In Duchenne muscular dystrophy, the exon-skipping approach has obtained proof of concept in animal models, myogenic cell cultures, and following local and systemic administration in Duchenne patients. Indeed, we have previously demonstrated that low doses (7.5 mg/Kg/week of 2′-O-methyl-phosphorothioate antisense oligoribonucleotides (AONs adsorbed onto ZM2 nanoparticles provoke widespread dystrophin restoration 7 days after intraperitoneal treatment in mdx mice. In this study, we went on to test whether this dystrophin restoration was still measurable 90 days from the end of the same treatment. Interestingly, we found that both western blot and immunohistochemical analysis (up to 7% positive fibres were still able to detect dystrophin protein in the skeletal muscles of ZM2-AON-treated mice at this time, and the level of exon-23 skipping could still be assessed by RT real-time PCR (up to 10% of skipping percentage. In contrast, the protein was undetectable by western blot analysis in the skeletal muscles of mdx mice treated with an identical dose of naked AON, and the percentage of dystrophin-positive fibres and exon-23 skipping were reminiscent of those of untreated mdx mice. Our data therefore demonstrate the long-term residual efficacy of this systemic low-dose treatment and confirm the protective effect nanoparticles exert on AON molecules.

Estimation of genetic variability and selection response for clutch length in dwarf brown-egg layers carrying or not the naked neck gene

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Tixier-Boichard Michèle

2003-03-01

Full Text Available Abstract In order to investigate the possibility of using the dwarf gene for egg production, two dwarf brown-egg laying lines were selected for 16 generations on average clutch length; one line (L1 was normally feathered and the other (L2 was homozygous for the naked neck gene NA. A control line from the same base population, dwarf and segregating for the NA gene, was maintained during the selection experiment under random mating. The average clutch length was normalized using a Box-Cox transformation. Genetic variability and selection response were estimated either with the mixed model methodology, or with the classical methods for calculating genetic gain, as the deviation from the control line, and the realized heritability, as the ratio of the selection response on cumulative selection differentials. Heritability of average clutch length was estimated to be 0.42 ± 0.02, with a multiple trait animal model, whereas the estimates of the realized heritability were lower, being 0.28 and 0.22 in lines L1 and L2, respectively. REML estimates of heritability were found to decline with generations of selection, suggesting a departure from the infinitesimal model, either because a limited number of genes was involved, or their frequencies were changed. The yearly genetic gains in average clutch length, after normalization, were estimated to be 0.37 ± 0.02 and 0.33 ± 0.04 with the classical methods, 0.46 ± 0.02 and 0.43 ± 0.01 with animal model methodology, for lines L1 and L2 respectively, which represented about 30% of the genetic standard deviation on the transformed scale. Selection response appeared to be faster in line L2, homozygous for the NA gene, but the final cumulated selection response for clutch length was not different between the L1 and L2 lines at generation 16.

Social status and sex effects on neural morphology in Damaraland mole-rats, Fukomys damarensis.

Science.gov (United States)

Anyan, Jeff J; Seney, Marianne L; Holley, Amanda; Bengston, Lynn; Goldman, Bruce D; Forger, Nancy G; Holmes, Melissa M

2011-01-01

We previously reported that in a eusocial rodent, the naked mole-rat (Heterocephalus glaber), traditional neural sex differences were absent; instead, neural dimorphisms were associated with breeding status. Here we examined the same neural regions previously studied in naked mole-rats in a second eusocial species, the Damaraland mole-rat (Fukomys damarensis). Damaraland mole-rats live in social groups with breeding restricted to a small number of animals. However, colony sizes are much smaller in Damaraland mole-rats than in naked mole-rats and there is consequently less reproductive skew. In this sense, Damaraland mole-rats may be considered intermediate in social organization between naked mole-rats and more traditional laboratory rodents. We report that, as in naked mole-rats, breeding Damaraland mole-rats have larger volumes of the principal nucleus of the bed nucleus of the stria terminalis and paraventricular nucleus of the hypothalamus than do subordinates, with no effect of sex on these measures. Thus, these structures may play special roles in breeders of eusocial species. However, in contrast to what was seen in naked mole-rats, we also found sex differences in Damaraland mole-rats: volume of the medial amygdala and motoneuron number in Onuf's nucleus were both greater in males than in females, with no significant effect of breeding status. Thus, both sex and breeding status influence neural morphology in Damaraland mole-rats. These findings are in accord with the observed sex differences in body weight and genitalia in Damaraland but not naked mole-rats. We hypothesize that the increased sexual dimorphism in Damaraland mole-rats relative to naked mole-rats is related to reduced reproductive skew. 2011 S. Karger AG, Basel.

Social structure predicts genital morphology in African mole-rats.

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Marianne L Seney

2009-10-01

Full Text Available African mole-rats (Bathyergidae, Rodentia exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure.We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate.The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology.

Social structure predicts genital morphology in African mole-rats.

Science.gov (United States)

Seney, Marianne L; Kelly, Diane A; Goldman, Bruce D; Sumbera, Radim; Forger, Nancy G

2009-10-15

African mole-rats (Bathyergidae, Rodentia) exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure. We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate. The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology.

[Parasitologic significance of the alteration of the causative Anisakidae worm and of the Pseudoterranova decipiens female immature adult worm, casting off the cuticles, and excreted from human in Kanazawa City].

Science.gov (United States)

Ishikura, H; Kikuchi, K; Akao, N; Doutei, M; Yagi, K; Takahashi, S; Sato, N

1995-09-01

We have been studying Anisakidae larvae, their intermediate hosts and their final hosts in the northern Japan Sea area. These larvae cause anisakidosis. According to the investigation, the recent burst of pseudoterranovosis in this area can be attributed to the increased presence of sea lions, which proliferate in the Arctic region, then migrate to the northern Japan Sea and eat the intermediate host fish. In a stomach of a male sea lion that was captured in February 1995, we found more than 4,500 Pseudoterranova decipiens. Although there is no known circumstance in which a human would consume an adult worm of Anisakis nematode, an astonishing case of this was found in Kanazawa; a female young adult Pseudoterranova decipiens undergoing the final metamorphosis was emitted from a patient. This indicates that the Anisakis larva can mature into the adult worm in humans. It is postulated that the Pseudoterranova decipiens larva is in the process of adapting to use humans as the final host.

INFLUÊNCIA DO CULTIVO CONSORCIADO DE AVEIA PRETA (AVENA STRIGOSA SCHIEB. E ERVILHACA COMUM (VICIA SATIVA L. NA PRODUÇÃO DE FITOMASSA E NO APORTE DE NITROGÊNIO INFLUENCE OF INTERCROPPED COMMON VETCH (VICIA SATIVA L. AND NAKED OAT (AVENA STRIGOSA ON BIOMASS PRODUCTION AND NITROGEN ADDITION

Directory of Open Access Journals (Sweden)

R. Heinrichs

1999-01-01

Full Text Available Em um Podzólico Vermelho Amarelo e sob preparo convencional, foi avaliada a influência de proporções de sementes de ervilhaca (Vicia sativa L. e de aveia preta (Avena strigosa Schieb. cultivadas em consórcio, na produção de fitomassa e no aporte de nitrogênio no sistema. O experimento foi implantado em solo podzolico vermelho amarelo, de Santa Maria, RS. Os tratamentos foram casualizados em quatro blocos, constituindo-se de: 1- 100% Ervilhaca comum (E; 2- 90% E + 10% Aveia preta (A; 3- 75% E + 25% A; 4- 50% E + 50% A; 5- 25% E + 75% A; 6- 100% A; 7- pousio de inverno. A amostragem da fitomassa das coberturas verdes foi efetuada na ocasião do pleno florescimento em área de 0,8m2 por parcela. Os resultados evidenciaram que a aveia preta e a ervilhaca comum podem ser consorciadas, beneficiando assim, a produção de fitomassa e acúmulo de nitrogênio.The effect of intercropping common vetch (Vicia sativa L. with naked oat (Avena strigosa Schieb. at different seed proportions was evaluated. The trial was set up on a Red Yellow Podzolic soil of Santa Maria, RS, Brazil. The treatments were the following: 1- 100% E (common vetch; 2- 90% E + 10% A (naked oat; 3- 75% E + 25% A; 4- 50% E + 50% A; 5- 25% E + 75% A; 6- 100% A; 7- fall tillage organized in four randomized blocks. Biomass production was evaluated at the flowering stage in an area of 0.8 m2 per plot. Data show that both species can be intercropped which is beneficial to biomass production and nitrogen accumulation.

LA CONFIGURACIÓN DEL SIGLO XXI EN LA POÉTICA DE DANA GELINAS

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GLORIA VERGARA

2013-05-01

Full Text Available In this article we will study the poetry of Dana Gelinas, highlighting the strategies to representing the contemporary world. This Mexican poetess sees humans as entranced in front of windows or powerlessin the social struggle. Dana Gelinas’ poetry is naked and strong like the desert. Her verse come without much of preamble to define the image of the 21st century.

Micromorphology and development of the epicuticular structure on the epidermal cell of ginseng leaves

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Kyounghwan Lee

2015-04-01

Conclusion: The outwardly projected cuticle and epidermal cell wall (i.e., an epicuticular wrinkle acts as a major barrier to block out sunlight in ginseng leaves. The small vesicles in the peripheral region of epidermal cells may suppress the cuticle and parts of epidermal wall, push it upward, and consequently contribute to the formation of the epicuticular structure.

Br-rich tips of calcified crab claws are less hard but more fracture resistant: a comparison of mineralized and heavy-element biological materials.

Science.gov (United States)

Schofield, Robert M S; Niedbala, Jack C; Nesson, Michael H; Tao, Ye; Shokes, Jacob E; Scott, Robert A; Latimer, Matthew J

2009-06-01

We find that the spoon-like tips of the chelipeds (large claws) of the crab Pachygrapsus crassipes differ from the rest of the claw in that they are not calcified, but instead contain about 1% bromine--thus they represent a new example of a class of structural biological materials that contain heavy elements such as Zn, Mn, Fe, Cu, and Br bound in an organic matrix. X-ray absorption spectroscopy data suggest that the bromine is bound to phenyl rings, possibly in tyrosine. We measure a broad array of mechanical properties of a heavy-element biological material for the first time (abrasion resistance, coefficient of kinetic friction, energy of fracture, hardness, modulus of elasticity and dynamic mechanical properties), and we make a direct comparison with a mineralized tissue. Our results suggest that the greatest advantage of bromine-rich cuticle over calcified cuticle is resistance to fracture (the energy of fracture is about an order of magnitude greater than for calcified cuticle). The greatest advantage relative to unenriched cuticle, represented by ant mandible cuticle, is a factor of about 1.5 greater hardness and modulus of elasticity.The spoon-like tips gain additional fracture resistance from the orientation of the constituent laminae and from the viscoelasticity of the material. We suggest that fracture resistance is of greater importance in smaller organisms, and we speculate that one function of heavy elements in structural biological materials is to reduce molecular resonant frequencies and thereby increase absorption of energy from impacts.

Mutation of a cuticular protein, BmorCPR2, alters larval body shape and adaptability in silkworm, Bombyx mori.

Science.gov (United States)

Qiao, Liang; Xiong, Gao; Wang, Ri-xin; He, Song-zhen; Chen, Jie; Tong, Xiao-ling; Hu, Hai; Li, Chun-lin; Gai, Ting-ting; Xin, Ya-qun; Liu, Xiao-fan; Chen, Bin; Xiang, Zhong-huai; Lu, Cheng; Dai, Fang-yin

2014-04-01

Cuticular proteins (CPs) are crucial components of the insect cuticle. Although numerous genes encoding cuticular proteins have been identified in known insect genomes to date, their functions in maintaining insect body shape and adaptability remain largely unknown. In the current study, positional cloning led to the identification of a gene encoding an RR1-type cuticular protein, BmorCPR2, highly expressed in larval chitin-rich tissues and at the mulberry leaf-eating stages, which is responsible for the silkworm stony mutant. In the Dazao-stony strain, the BmorCPR2 allele is a deletion mutation with significantly lower expression, compared to the wild-type Dazao strain. Dysfunctional BmorCPR2 in the stony mutant lost chitin binding ability, leading to reduced chitin content in larval cuticle, limitation of cuticle extension, abatement of cuticle tensile properties, and aberrant ratio between internodes and intersegmental folds. These variations induce a significant decrease in cuticle capacity to hold the growing internal organs in the larval development process, resulting in whole-body stiffness, tightness, and hardness, bulging intersegmental folds, and serious defects in larval adaptability. To our knowledge, this is the first study to report the corresponding phenotype of stony in insects caused by mutation of RR1-type cuticular protein. Our findings collectively shed light on the specific role of cuticular proteins in maintaining normal larval body shape and will aid in the development of pest control strategies for the management of Lepidoptera.

Distribution and uptake dynamics of mercury in leaves of common deciduous tree species in Minnesota, U.S.A.

Science.gov (United States)

Aicam Laacouri; Edward A. Nater; Randall K. Kolka

2013-01-01

A sequential extraction technique for compartmentalizing mercury (Hg) in leaves was developed based on a water extraction of Hg from the leaf surface followed by a solvent extraction of the cuticle. The bulk of leaf Hg was found in the tissue compartment (90-96%) with lesser amounts in the surface and cuticle compartments. Total leaf concentrations of Hg varied among...

Preparation and mounting of adult Drosophila structures in Canada balsam.

Science.gov (United States)

Stern, David L; Sucena, Elio

2012-03-01

The Drosophila cuticle carries a rich array of morphological details. Thus, cuticle examination has had a central role in the history of genetics. To prepare fine "museum-quality," permanent slides, it is best to mount specimens in Canada Balsam. It is difficult to give precise recipes for Canada Balsam, because every user seems to prefer a slightly different viscosity. Dilute solutions spread easily and do not dry too rapidly while mounting specimens. The disadvantage is that there is actually less Balsam in a "drop" of the solution, and when dried, it can contract from the sides of the coverslip, sometimes disturbing the specimen. Unfortunately, there is no substitute for experience when using Canada Balsam. This protocol describes a procedure for mounting adult cuticles in Canada Balsam.

In vivo silencing of alpha-synuclein using naked siRNA

OpenAIRE

Charisse Klaus; Toudjarska Ivanka; Kent Caroline; Hinkle Kelly; Ogholikhan Sina; He Zhen; Braithwaite Adam; Lincoln Sarah; Zehr Cynthia; Hope Andrew; Bumcrot David; Melrose Heather; Lewis Jada; Braich Ravi; Pandey Rajendra K

2008-01-01

Abstract Background Overexpression of α-synuclein (SNCA) in families with multiplication mutations causes parkinsonism and subsequent dementia, characterized by diffuse Lewy Body disease post-mortem. Genetic variability in SNCA contributes to risk of idiopathic Parkinson's disease (PD), possibly as a result of overexpression. SNCA downregulation is therefore a valid therapeutic target for PD. Results We have identified human and murine-specific siRNA molecules which reduce SNCA in vitro. As a...

Defective Pollen Wall 2 ( DPW2 ) Encodes an Acyl Transferase Required for Rice Pollen Development

Energy Technology Data Exchange (ETDEWEB)

Xu, Dawei [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Shi, Jianxin [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Rautengarten, Carsten [Univ. of Melbourne (Australia). ARC Centre of Excellence in Plant Cell Walls; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Yang, Li [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Qian, Xiaoling [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Uzair, Muhammad [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Zhu, Lu [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Luo, Qian [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; An, Gynheung [Kyung Hee Univ., Yongin (Korea). Crop Biotech Inst.; Waßmann, Fritz [Univ. of Bonn (Germany). Inst. of Cellular and Molecular Botany; Schreiber, Lukas [Univ. of Bonn (Germany). Inst. of Cellular and Molecular Botany; Heazlewood, Joshua L. [Univ. of Melbourne (Australia). ARC Centre of Excellence in Plant Cell Walls; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Scheller, Henrik Vibe [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Univ. of California, Berkeley, CA (United States). Dept. of Plant and Microbial Biology; Hu, Jianping [Michigan State Univ., East Lansing, MI (United States). Dept. of Energy Plant Research Lab.; Zhang, Dabing [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Univ. of Adelaide, SA (Australia). School of Agriculture, Food and Wine; Liang, Wanqi [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences

2016-05-31

Aliphatic and aromatic lipids are both essential structural components of the plant cuticle, an important interface between the plant and environment. Although cross links between aromatic and aliphatic or other moieties are known to be associated with the formation of leaf cutin and root and seed suberin, the contribution of aromatic lipids to the biosynthesis of anther cuticles and pollen walls remains elusive. In this study, we characterized the rice (Oryza sativa) male sterile mutant, defective pollen wall 2 (dpw2), which showed an abnormal anther cuticle, a defective pollen wall, and complete male sterility. Compared with the wild type, dpw2 anthers have increased amounts of cutin and waxes and decreased levels of lipidic and phenolic compounds. DPW2 encodes a cytoplasmically localized BAHD acyltransferase. In vitro assays demonstrated that recombinant DPW2 specifically transfers hydroxycinnamic acid moieties, using v-hydroxy fatty acids as acyl acceptors and hydroxycinnamoyl-CoAs as acyl donors. Thus, The cytoplasmic hydroxycinnamoyl-CoA:v-hydroxy fatty acid transferase DPW2 plays a fundamental role in male reproduction via the biosynthesis of key components of the anther cuticle and pollen wall.

Shasta ground sloth ( Nothrotheriops shastense hoffstetter) at Shelter Cave, New Mexico: Environment, diet, and extinction

Science.gov (United States)

Thompson, Robert S.; Van Devender, Thomas R.; Martin, Paul S.; Foppe, Theresa; Long, Austin

1980-11-01

Seven coprolites of the extinct Shasta ground sloth ( Nothrotheriops shastense) were recently discovered in the Los Angeles County Museum collection from Shelter Cave, New Mexico. Three dung balls provided radiocarbon ages of 11,330, 12,330 and 12,430 yr B.P. Packrat ( Neotoma) middens disclose a xeric juniper woodland at Shelter Cave during the sloth's occupation. Plant cuticles from the dung indicate that the ground sloth had a diet dominated by mormon tea ( Ephedra) and other xerophytic shrubs. Pollen spectra from the coprolites have high representations of anemophilous plants and low representations of the dietary items shown in the cuticle analysis. Fifteen radiocarbon dates of sloth dung obtained since 1974 strengthen the hypothesis that sloth extinction occurred about 11,000 yr B.P. Paleoenvironmental studies indicate that ground sloths lived in juniper woodlands and montane conifer communities. Nothrotheriops commonly dined on shrubs that are still present in these habitats. It is difficult to explain the demise of the Shasta ground sloth by climatic change or dietary stress. Human predation remains as a possible explanation; ground sloth extinction appears to coincide with the time of Clovis mammoth hunters.

Why Is She Naked?

DEFF Research Database (Denmark)

Rodil, Kasper; Winschiers-Theophilus, Heike

2018-01-01

with a refinement of the previously presented Tripartite Digitisation Model (TDM). We begin by providing a short recapitulation of the TDM originally published in Vol. 10, with an emphasis on the role of evaluations. This model is exemplified with a concrete example of digitisation of ICH together with an Ova...

VEGF-C gene therapy augments postnatal lymphangiogenesis and ameliorates secondary lymphedema

OpenAIRE

Yoon, Young-sup; Murayama, Toshinori; Gravereaux, Edwin; Tkebuchava, Tengiz; Silver, Marcy; Curry, Cynthia; Wecker, Andrea; Kirchmair, Rudolf; Hu, Chun Song; Kearney, Marianne; Ashare, Alan; Jackson, David G.; Kubo, Hajime; Isner, Jeffrey M.; Losordo, Douglas W.

2003-01-01

Although lymphedema is a common clinical condition, treatment for this disabling condition remains limited and largely ineffective. Recently, it has been reported that overexpression of VEGF-C correlates with increased lymphatic vessel growth (lymphangiogenesis). However, the effect of VEGF-C–induced lymphangiogenesis on lymphedema has yet to be demonstrated. Here we investigated the impact of local transfer of naked plasmid DNA encoding human VEGF-C (phVEGF-C) on two animal models of lymphed...

Burkholderia pseudomallei Data Gap Analysis

Science.gov (United States)

2015-11-01

Since its discovery , B. pseudomallei has become recognized as a significant public health threat in the tropical regions of the globe where it is...alcoholics, kava users (Australia), chronic drug users, or diabetic. However, HIV does not seem to be a factor. Table 2-1. Published melioidosis...However, the history for these types of vaccines has shown better efficacy in mouse models that in human trials. In addition to the naked-DNA

A SEM-correlation of the anatomy of the vitreous body: making visible the invisible.

Science.gov (United States)

Jongebloed, W L; Humalda, D; Worst, J F

1986-12-30

The naked human vitreous (sclera, iris and cornea removed) suspended in water does not reveal inner structures. After ink injection into the vitreous, the presence of different compartments and the existence of cisterns becomes evident. A concept of the internal system of cisterns is given on the basis of stereoscopic-lightmicroscopic images. An attempt is made to correlate images of the complete vitreous body, obtained with a stereo-lightmicroscope, with images of segments of cisternal walls produced with a scanning electron-microscope (SEM). A comparison is made between SEM-images of the vitreous bodies of human and rabbit eyes.

Characterization and genetic mapping of eceriferum-ym (cer-ym), a cutin deficient barley mutant with impaired leaf water retention capacity.

Science.gov (United States)

Li, Chao; Liu, Cheng; Ma, Xiaoying; Wang, Aidong; Duan, Ruijun; Nawrath, Christiane; Komatsuda, Takao; Chen, Guoxiong

2015-09-01

The cuticle covers the aerial parts of land plants, where it serves many important functions, including water retention. Here, a recessive cuticle mutant, eceriferum-ym (cer-ym), of Hordeum vulgare L. (barley) showed abnormally glossy spikes, sheaths, and leaves. The cer-ym mutant plant detached from its root system was hypersensitive to desiccation treatment compared with wild type plants, and detached leaves of mutant lost 41.8% of their initial weight after 1 h of dehydration under laboratory conditions, while that of the wild type plants lost only 7.1%. Stomata function was not affected by the mutation, but the mutant leaves showed increased cuticular permeability to water, suggesting a defective leaf cuticle, which was confirmed by toluidine blue staining. The mutant leaves showed a substantial reduction in the amounts of the major cutin monomers and a slight increase in the main wax component, suggesting that the enhanced cuticle permeability was a consequence of cutin deficiency. cer-ym was mapped within a 0.8 cM interval between EST marker AK370363 and AK251484, a pericentromeric region on chromosome 4H. The results indicate that the desiccation sensitivity of cer-ym is caused by a defect in leaf cutin, and that cer-ym is located in a chromosome 4H pericentromeric region.

In Situ Nondestructive Analysis of Kalanchoe pinnata Leaf Surface Structure by Polarization-Modulation Infrared Reflection-Absorption Spectroscopy.

Science.gov (United States)

Hama, Tetsuya; Kouchi, Akira; Watanabe, Naoki; Enami, Shinichi; Shimoaka, Takafumi; Hasegawa, Takeshi

2017-12-14

The outermost surface of the leaves of land plants is covered with a lipid membrane called the cuticle that protects against various stress factors. Probing the molecular-level structure of the intact cuticle is highly desirable for understanding its multifunctional properties. We report the in situ characterization of the surface structure of Kalanchoe pinnata leaves using polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS). Without sample pretreatment, PM-IRRAS measures the IR spectra of the leaf cuticle of a potted K. pinnata plant. The peak position of the CH 2 -related modes shows that the cuticular waxes on the leaf surface are mainly crystalline, and the alkyl chains are highly packed in an all-trans zigzag conformation. The surface selection rule of PM-IRRAS revealed the average orientation of the cuticular molecules, as indicated by the positive and negative signals of the IR peaks. This unique property of PM-IRRAS revealed that the alkyl chains of the waxes and the main chains of polysaccharides are oriented almost perpendicular to the leaf surface. The nondestructive, background-free, and environmental gas-free nature of PM-IRRAS allows the structure and chemistry of the leaf cuticle to be studied directly in its native environment.

Genetic and phenotypic relationships between immune defense, melanism and life-history traits at different temperatures and sexes in Tenebrio molitor.

Science.gov (United States)

Prokkola, J; Roff, D; Kärkkäinen, T; Krams, I; Rantala, M J

2013-08-01

Insect cuticle melanism is linked to a number of life-history traits, and a positive relationship is hypothesized between melanism and the strength of immune defense. In this study, the phenotypic and genetic relationships between cuticular melanization, innate immune defense, individual development time and body size were studied in the mealworm beetle (Tenebrio molitor) using three different temperatures with a half-sib breeding design. Both innate immune defense and cuticle darkness were higher in females than males, and a positive correlation between the traits was found at the lowest temperature. The effect of temperature on all the measured traits was strong, with encapsulation ability and development time decreasing and cuticle darkness increasing with a rise in temperature, and body size showing a curved response. The analysis showed a highly integrated system sensitive to environmental change involving physiological, morphological and life-history traits.

Pathogenicity induced by the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae in Agrotisipsilon (Hufn.)

International Nuclear Information System (INIS)

Fouda, M.A.; Abas, A.A.; Ibrahium, A.A.; Salem, H.; Gabarty, A.

2012-01-01

Scanning electron microscopy (SEM) allowed to observe B. bassiana and M. anisopliae adhesion and penetration structure on A. ipsilon larvae treated with the Lc 50 of the fungus, B. bassiana revealed adhesion and penetration structures in the infected larvae. Growth of the fungus on the infected larvae and signs of hyphal penetration of insect cuticle as well as proliferation of the cuticle were also appeared. On the other hand, the fungus, M. anisopliaeas declared by SEM showed a dense network together and caused the green spores on the insect cuticle. Also, SEM allowed observing the spores and hyphae of the fungus in the body cavity of infected larvae. Scanning electron microscopy is convenient tools to observe the mode of action of entomopathogenic fungi and to observe how they are able to colonize and infect the host.

Classification and infection mechanism of entomopathogenic fungi

OpenAIRE

Mora, Margy Alejandra Esparza; Castilho, Alzimiro Marcelo Conteiro; Fraga, Marcelo Elias

2018-01-01

ABSTRACT: Entomopathogenic fungi are important biological control agents throughout the world, have been the subject of intensive research for more than 100 years, and can occur at epizootic or enzootic levels in their host populations. Their mode of action against insects involves attaching a spore to the insect cuticle, followed by germination, penetration of the cuticle, and dissemination inside the insect. Strains of entomopathogenic fungi are concentrated in the following orders: Hypocre...

Pathogencity induced by the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae in Agrotis ipsilon (Hufn.

Directory of Open Access Journals (Sweden)

A. Gabarty

2014-01-01

Full Text Available Scanning electron microscopy (SEM allowed observing Beauveria bassiana and Metarhizium anisopliae adhesion and penetration structure on Agrotis ipsilon larvae. SEM of A. ipsilon larvae treated with the Lc50 of the fungus, B. bassiana revealed adhesion and penetration structures in the infected larvae. Growth of the fungus on the infected larvae and signs of hyphal penetration of insect cuticle as well as proliferation of the cuticle were also appearing. On the other hand, the fungus, M. anisopliae as declared by SEM showed a dense network together and cause the green spores on the insect cuticle. Also, SEM allowed observing the spores and hyphae of the fungus in the body cavity of infected larvae. Scanning electron microscopy is allowed tool to observe the mode of action of entomopathogenic fungi and to observe how they are able to colonize and infect the host.

Investigations of oocyte in vitro maturation within a mouse model.

Science.gov (United States)

Chin, Alexis Heng Boon; Chye, Ng Soon

2004-02-01

This study attempted to develop a 'less meiotically competent' murine model for oocyte in vitro maturation (IVM), which could more readily be extrapolated to human clinical assisted reproduction. Oocyte meiotic competence was drastically reduced upon shortening the standard duration of in vivo gonadotrophin stimulation from 48 h to 24 h, and by selecting only naked or partially naked germinal vesicle oocytes, instead of fully cumulus enclosed oocyte complexes. With such a less meiotically competent model, only porcine granulosa coculture significantly enhanced the oocyte maturation rate in vitro, whereas no significant enhancement was observed with macaque and murine granulosa coculture. Increased serum concentrations and the supplementation of gonadotrophins, follicular fluid and extracellular matrix gel within the culture medium did not enhance IVM under either cell-free or coculture conditions. Culture medium conditioned by porcine granulosa also enhanced the maturation rate, and this beneficial effect was not diminished upon freeze-thawing. Enhanced IVM in the presence of porcine granulosa coculture did not, however, translate into improved developmental competence, as assessed by in vitro fertilization and embryo culture to the blastocyst stage.

Insect Analogue to the Lotus Leaf: A Planthopper Wing Membrane Incorporating a Low-Adhesion, Nonwetting, Superhydrophobic, Bactericidal, and Biocompatible Surface.

Science.gov (United States)

Watson, Gregory S; Green, David W; Cribb, Bronwen W; Brown, Christopher L; Meritt, Christopher R; Tobin, Mark J; Vongsvivut, Jitraporn; Sun, Mingxia; Liang, Ai-Ping; Watson, Jolanta A

2017-07-19

Nature has produced many intriguing and spectacular surfaces at the micro- and nanoscales. These small surface decorations act for a singular or, in most cases, a range of functions. The minute landscape found on the lotus leaf is one such example, displaying antiwetting behavior and low adhesion with foreign particulate matter. Indeed the lotus leaf has often been considered the "benchmark" for such properties. One could expect that there are animal counterparts of this self-drying and self-cleaning surface system. In this study, we show that the planthopper insect wing (Desudaba danae) exhibits a remarkable architectural similarity to the lotus leaf surface. Not only does the wing demonstrate a topographical likeness, but some surface properties are also expressed, such as nonwetting behavior and low adhering forces with contaminants. In addition, the insect-wing cuticle exhibits an antibacterial property in which Gram-negative bacteria (Porphyromonas gingivalis) are killed over many consecutive waves of attacks over 7 days. In contrast, eukaryote cell associations, upon contact with the insect membrane, lead to a formation of integrated cell sheets (e.g., among human stem cells (SHED-MSC) and human dermal fibroblasts (HDF)). The multifunctional features of the insect membrane provide a potential natural template for man-made applications in which specific control of liquid, solid, and biological contacts is desired and required. Moreover, the planthopper wing cuticle provides a "new" natural surface with which numerous interfacial properties can be explored for a range of comparative studies with both natural and man-made materials.

Conservação de tangerina cv. Clemenules utilizando diferentes recobrimentos = Conservation of Mandarins cv. Clemenules with different cuticles

Directory of Open Access Journals (Sweden)

Rosa de Oliveira Treptow

2007-01-01

Full Text Available O objetivo deste trabalho foi verificar os efeitos de diferentes recobrimentos e períodos de armazenamento na conservação de tangerinas Clemenules. Após a colheita, as frutas foram submetidas ao pré-resfriamento por 12 horas a 5ºC e em seguida, aos seguintes tratamentos: T1 testemunha; T2 filme de polietileno microperfurado; T3 filme de polietileno não perfurado; T4 cera de carnaúba a 50%, diluída em água; T5 cera de carnaúba a 100% (não diluída. As tangerinas foram armazenadas por 20, 40 e 60 dias em temperatura de 5ºC e UR de 90-95%, depois foram mantidas em temperatura de 15±1ºC e UR de 75-80%, durante quatro dias simulando a comercialização. Na colheita e após cada período de armazenamento, seguido de simulação decomercialização, foram avaliadas as variáveis: perda de massa; cor; sólidos solúveis (SS; acidez titulável (AT; relação SS/AT; podridões, distúrbios fisiológicos e características sensoriais. Amodificação da atmosfera reduziu a perda de massa, a incidência de distúrbios e podridões de tangerinas Clemenules durante o armazenamento. As frutas acondicionadas em filme de polietilenosem perfuração ou aquelas revestidas com cera sem diluição apresentaram sabor estranho e menor qualidade geral. Tangerinas ‘Clemenules’ acondicionadas em filme de polietileno microperfurado ecera diluída em 50% de água podem ser armazenadas durante 60 dias a 5ºC e comercializadas durante quatro dias a 15±1ºC sem comprometer a qualidade sensorial.The aim of this work was to evaluate the effects of different cuticles and storage periods on the conservation of mandarins cv. Clemenules. After harvest the fruits were kept at 5ºC during 12 hours. Then, they were submitted to the following treatments: T1 control; T2 micro perforated polyethylene bag; T3 non-perforated polyethylene bag; T4 carnauba wax at 50% in water; T5 carnauba wax at 100% (without dilution. The mandarins were stored for 20, 40 and 60 days at 5

Compression map, functional groups and fossilization: A chemometric approach (Pennsylvanian neuropteroid foliage, Canada)

Science.gov (United States)

D'Angelo, J. A.; Zodrow, E.L.; Mastalerz, Maria

2012-01-01

Nearly all of the spectrochemical studies involving Carboniferous foliage of seed-ferns are based on a limited number of pinnules, mainly compressions. In contrast, in this paper we illustrate working with a larger pinnate segment, i.e., a 22-cm long neuropteroid specimen, compression-preserved with cuticle, the compression map. The objective is to study preservation variability on a larger scale, where observation of transparency/opacity of constituent pinnules is used as a first approximation for assessing the degree of pinnule coalification/fossilization. Spectrochemical methods by Fourier transform infrared spectrometry furnish semi-quantitative data for principal component analysis.The compression map shows a high degree of preservation variability, which ranges from comparatively more coalified pinnules to less coalified pinnules that resemble fossilized-cuticles, noting that the pinnule midveins are preserved more like fossilized-cuticles. A general overall trend of coalified pinnules towards fossilized-cuticles, i.e., variable chemistry, is inferred from the semi-quantitative FTIR data as higher contents of aromatic compounds occur in the visually more opaque upper location of the compression map. The latter also shows a higher condensation of the aromatic nuclei along with some variation in both ring size and degree of aromatic substitution. From principal component analysis we infer correspondence between transparency/opacity observation and chemical information which correlate with varying degree to fossilization/coalification among pinnules. ?? 2011 Elsevier B.V.

Meloidogyne incognita Fatty Acid- and Retinol- Binding Protein (Mi-FAR-1) Affects Nematode Infection of Plant Roots and the Attachment of Pasteuria penetrans Endospores.

Science.gov (United States)

Phani, Victor; Shivakumara, Tagginahalli N; Davies, Keith G; Rao, Uma

2017-01-01

Root-knot nematode (RKN) Meloidogyne incognita is an economically important pest of crops. Pasteuria penetrans , is a nematode hyperparasitic bacterium capable of suppressing the reproduction of RKN and thereby useful for its management. Secreted fatty acid and retinol-binding proteins are unique in nematodes and are engaged in nutrient acquisition, development and reproduction; they are also a component of the nematode cuticle and thought to be involved in the interface between hosts and parasites. Attachment of endospores to the cuticle of second stage juveniles of RKN is the primary step of infection and several factors have been identified to facilitate attachment. In this study, the full length of Mi-far-1 (573 bp) was cloned from M. incognita and characterized. Analysis revealed that the Mi-far-1 was rich in α-helix structure, contained a predicted consensus casein kinase II phosphorylation site and a glycosylation site. Quantitative PCR showed the highest expression in the fourth stage juveniles and in situ hybridization revealed the presence of Mi-far-1 mRNA in the hypodermis below the cuticle. Single copy insertion pattern of Mi-far-1 in M. incognita genome was detected by Southern blotting. Knockdown of Mi-far-1 showed significantly increased attachment of P. penetrans' endospores on juvenile cuticle surface and also affected host finding, root infection and nematode fecundity.

Histochemistry of lectin-binding sites in Halicryptus spinulosus (Priapulida).

Science.gov (United States)

Busch, A; Schumacher, U; Storch, V

2001-02-01

Priapulida represent one of the phylogenetically oldest multicellular animal groups. In multicellular animals (Metazoa) cell-to-cell and cell-to-matrix interactions are often mediated by carbohydrate residues of glycoconjugates. To analyze the carbohydrate composition of a phylogenetically old species, lectin histochemistry was employed on 5 specimens of the priapulid Halicryptus spinulosus. Many lectins bound to the chitin-containing cuticle, including those specific for carbohydrates other than N-acetylglucosamine, the principle building block of chitin. The connective tissue of the animals contained both N-acetylglucosamine and N-acetylgalactosamine. Mannose residues were widely distributed with the exception of the cuticle, but complex type carbohydrates were not present in the entire animal. Sialic acid residues were only detected in the cuticle and brush border of the intestinal epithelium, while fucose was limited to the cuticle. Thus, the lectin-binding pattern indicated that sugars typical for the linking region of both N- and O-glycoproteins in mammals are also present in H. spinulosus. Carbohydrate residues that are typical for the complex type of N-linked glycans in vertebrates are not present as are carbohydrate residues typical for the termination of O-linked carbohydrate chains. Hence, a truncated form of both N- and O-linked glycosylation is present in H. spinulosus indicating that more complex patterns of glycosylation developed later during evolution.

Meloidogyne incognita Fatty Acid- and Retinol- Binding Protein (Mi-FAR-1 Affects Nematode Infection of Plant Roots and the Attachment of Pasteuria penetrans Endospores

Directory of Open Access Journals (Sweden)

Victor Phani

2017-11-01

Full Text Available Root-knot nematode (RKN Meloidogyne incognita is an economically important pest of crops. Pasteuria penetrans, is a nematode hyperparasitic bacterium capable of suppressing the reproduction of RKN and thereby useful for its management. Secreted fatty acid and retinol-binding proteins are unique in nematodes and are engaged in nutrient acquisition, development and reproduction; they are also a component of the nematode cuticle and thought to be involved in the interface between hosts and parasites. Attachment of endospores to the cuticle of second stage juveniles of RKN is the primary step of infection and several factors have been identified to facilitate attachment. In this study, the full length of Mi-far-1 (573 bp was cloned from M. incognita and characterized. Analysis revealed that the Mi-far-1 was rich in α-helix structure, contained a predicted consensus casein kinase II phosphorylation site and a glycosylation site. Quantitative PCR showed the highest expression in the fourth stage juveniles and in situ hybridization revealed the presence of Mi-far-1 mRNA in the hypodermis below the cuticle. Single copy insertion pattern of Mi-far-1 in M. incognita genome was detected by Southern blotting. Knockdown of Mi-far-1 showed significantly increased attachment of P. penetrans’ endospores on juvenile cuticle surface and also affected host finding, root infection and nematode fecundity.

Advanced Design of Dumbbell-shaped Genetic Minimal Vectors Improves Non-coding and Coding RNA Expression.

Science.gov (United States)

Jiang, Xiaoou; Yu, Han; Teo, Cui Rong; Tan, Genim Siu Xian; Goh, Sok Chin; Patel, Parasvi; Chua, Yiqiang Kevin; Hameed, Nasirah Banu Sahul; Bertoletti, Antonio; Patzel, Volker

2016-09-01

Dumbbell-shaped DNA minimal vectors lacking nontherapeutic genes and bacterial sequences are considered a stable, safe alternative to viral, nonviral, and naked plasmid-based gene-transfer systems. We investigated novel molecular features of dumbbell vectors aiming to reduce vector size and to improve the expression of noncoding or coding RNA. We minimized small hairpin RNA (shRNA) or microRNA (miRNA) expressing dumbbell vectors in size down to 130 bp generating the smallest genetic expression vectors reported. This was achieved by using a minimal H1 promoter with integrated transcriptional terminator transcribing the RNA hairpin structure around the dumbbell loop. Such vectors were generated with high conversion yields using a novel protocol. Minimized shRNA-expressing dumbbells showed accelerated kinetics of delivery and transcription leading to enhanced gene silencing in human tissue culture cells. In primary human T cells, minimized miRNA-expressing dumbbells revealed higher stability and triggered stronger target gene suppression as compared with plasmids and miRNA mimics. Dumbbell-driven gene expression was enhanced up to 56- or 160-fold by implementation of an intron and the SV40 enhancer compared with control dumbbells or plasmids. Advanced dumbbell vectors may represent one option to close the gap between durable expression that is achievable with integrating viral vectors and short-term effects triggered by naked RNA.

Collapsing perfect fluid in self-similar five dimensional space-time and cosmic censorship

International Nuclear Information System (INIS)

Ghosh, S.G.; Sarwe, S.B.; Saraykar, R.V.

2002-01-01

We investigate the occurrence and nature of naked singularities in the gravitational collapse of a self-similar adiabatic perfect fluid in a five dimensional space-time. The naked singularities are found to be gravitationally strong in the sense of Tipler and thus violate the cosmic censorship conjecture

Naked DNA Immunization for Prevention of Prostate Cancer in a Dunning Rat Prostate Tumor Model

National Research Council Canada - National Science Library

Mincheff, Milcho

2004-01-01

... dendritic cells, The ability of dendritic cells (DCs), genetically modified with one of two types of plasmid DNA vaccines to stimulate lymphocytes from normal human donors and to generate antigen-specific responses, is compared...

Functional groups in a single pteridosperm species: Variability and circumscription (Pennsylvanian, Nova Scotia, Canada)

Science.gov (United States)

Zodrow, E.L.; Mastalerz, Maria

2007-01-01

Multiple foliar specimens of the Late Pennsylvanian fossil pteridosperm [gymnosperm] Alethopteris zeilleri (Ragot) Wagner were collected from one restricted stratigraphical horizon in the Canadian Sydney Coalfield. Variability of functional-group distribution using FTIR technique was studied in compressions, adaxial versus abaxial cuticles, and in unseparated cuticles as a function of maceration time from 48 to 168??h. The results obtained document spectral variability that could be expected within specimens of one species. For example, CH2/CH3 and Al/ox ratios can differ by as much as 20% of the values. Moreover, the experiments performed confirm that by using a previously established maceration protocol, long maceration periods do not bias FTIR spectra in terms of oxygenation overprinting. The inference that this cuticle is robust, under the given diagenetic level, probably reflects a reassuring degree of chemical fidelity of the Pennsylvanian plant to support Carboniferous chemotaxonomic observations. ?? 2006 Elsevier B.V. All rights reserved.

Analysis of variation in virulence of Beauveria bassiana against insect pests of pigeonpea using qPCR.

Science.gov (United States)

Senthilraja, Govindasamy; Anand, Theerthagiri; Mohankumar, Subbarayalu; Raguchander, Thiruvengadam; Samiyappan, Ramasamy

2018-03-01

Beauveria bassiana is a broad spectrum microbial bioagent used for the control of agriculturally important insect pests. However, in our experiments, two virulent isolates of B. bassiana (B2 and B10) showed specific preference toward Maruca vitrata and Helicoverpa armigera of pigeonpea. To better understand this feature, we developed a qPCR assay to quantify the chitinase (virulence factor) of B. bassiana during the infection process. Isolates of B. bassiana were grown on insect cuticle amended medium and minimal medium (without insect cuticle) to assess the induction of chitinase. Our results revealed a positive correlation between expression of chitinase by B. bassiana and the substrates (with or without cuticles of M. vitrata and H. armigera) used. This study showcases the methodology to quantify the chitinase and analysis of variation in virulence of B. bassiana (B2 and B10) against M. vitrata and H. armigera. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanics of biological polymer composites

Science.gov (United States)

Lomakin, Joseph

2009-12-01

Cartilage and cuticle are two natural materials capable of remarkable mechanical performance, especially considering the limitations on composition and processing conditions under which they are constructed. Their impressive properties are postulated to be a consequence of their complex multi-scale organization which has commonly been characterized by biochemical and microscopic methods. The objective of this dissertation is to overcome the limitations of such methods with mechanical analysis techniques generally reserved for the study of synthetic polymers. Methods for transient and dynamic mechanical analysis (DMA) of porcine TMJ disc sections and Tribolium castaneum and Tenebrio molitor elytral (modified forewing) cuticle were developed to characterize the mechanical performance of these biomaterials. The TMJ disc dynamic elastic modulus (E') was determined to be a strong function of disc orientation and pretension ranging from 700+/-240 kPa at (1g pretension) in the mediolateral direction to 73+/-8.5 MPa (150g preload) in the anteroposterior direction. Analogous mechanical testing was used to understand the relationship between composition and mechanical properties of beetle elytral cuticle at variable stages of maturation (tanning). Untanned elytra of both beetle species were ductile with a Young's modulus (E) of 44+/-8 MPa, but became brittle with an E of 2400+/-1100 MPa when fully tanned. Significantly, the E' of the TMJ disc and elytral cuticle exhibited a weak power law increase as a function of oscillation frequency. The exponent of the power law fit ( n) was determined to be a sensitive measure of molecular structure within these biomaterials. With increasing cuticular tanning, more so than with drying, the frequency dependence of cuticle E' diminished, suggesting cuticular cross-linking was an important component of tanning, as postulated by the quinone tanning hypothesis. The natural Black phenotype as well as TcADC iRNA suppressed Tribolium cuticle

Improved radiocarbon analyses of modern human hair to determine the year-of-death by cross-flow nanofiltered amino acids: common contaminants, implications for isotopic analysis, and recommendations.

Science.gov (United States)

Santos, Guaciara M; De La Torre, Hector A Martinez; Boudin, Mathieu; Bonafini, Marco; Saverwyns, Steven

2015-10-15

In forensic investigation, radiocarbon ((14)C) measurements of human tissues (i.e., nails and hair) can help determine the year-of-death. However, the frequent use of cosmetics can bias hair (14)C results as well as stable isotope values. Evidence shows that hair exogenous impurities percolate beyond the cuticle layer, and therefore conventional pretreatments are ineffective in removing them. We conducted isotopic analysis ((14)C, δ(13)C, δ(15)N and C/N) of conventionally treated and cross-flow nanofiltered amino acid (CFNAA)-treated samples (scalp- and body-hair) from a single female subject using fingernails as a reference. The subject studied frequently applies a permanent dark-brown dye kit to her scalp-hair and uses other care products for daily cleansing. We also performed pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analyses of CFNAA-treated scalp-hair to identify contaminant remnants that could possibly interfere with isotopic analyses. The conventionally treated scalp- and body-hair showed (14)C offsets of ~21‰ and ~9‰, respectively. These offsets confirm the contamination by petrochemicals in modern human hair. A single CFNAA extraction reduced those offsets by ~34%. No significant improvement was observed when sequential extractions were performed, as it appears that the procedure introduced some foreign contaminants. A chromatogram of the CFNAA scalp-hair pyrolysis products showed the presence of petroleum and plant/animal compound residues, which can bias isotopic analyses. We have demonstrated that CFNAA extractions can partially remove cosmetic contaminants embedded in human hair. We conclude that fingernails are still the best source of keratin protein for year-of-death determinations and isotopic analysis, with body-hair and/or scalp-hair coupled with CFNAA extraction a close second. Copyright © 2015 John Wiley & Sons, Ltd.

The naked truth: the face and body sensitive N170 response is enhanced for nude bodies.

Directory of Open Access Journals (Sweden)

Jari K Hietanen

Full Text Available Recent event-related potential studies have shown that the occipitotemporal N170 component--best known for its sensitivity to faces--is also sensitive to perception of human bodies. Considering that in the timescale of evolution clothing is a relatively new invention that hides the bodily features relevant for sexual selection and arousal, we investigated whether the early N170 brain response would be enhanced to nude over clothed bodies. In two experiments, we measured N170 responses to nude bodies, bodies wearing swimsuits, clothed bodies, faces, and control stimuli (cars. We found that the N170 amplitude was larger to opposite and same-sex nude vs. clothed bodies. Moreover, the N170 amplitude increased linearly as the amount of clothing decreased from full clothing via swimsuits to nude bodies. Strikingly, the N170 response to nude bodies was even greater than that to faces, and the N170 amplitude to bodies was independent of whether the face of the bodies was visible or not. All human stimuli evoked greater N170 responses than did the control stimulus. Autonomic measurements and self-evaluations showed that nude bodies were affectively more arousing compared to the other stimulus categories. We conclude that the early visual processing of human bodies is sensitive to the visibility of the sex-related features of human bodies and that the visual processing of other people's nude bodies is enhanced in the brain. This enhancement is likely to reflect affective arousal elicited by nude bodies. Such facilitated visual processing of other people's nude bodies is possibly beneficial in identifying potential mating partners and competitors, and for triggering sexual behavior.

40 CFR 65.7 - Monitoring, recordkeeping, and reporting waivers and alternatives, and alternative work practice...

Science.gov (United States)

2010-07-01

... require monitoring with a 40 CFR part 60, appendix A-7, Method 21 monitor. (3) Imaging means making visible emissions that may otherwise be invisible to the naked eye. (4) Optical gas imaging instrument means an instrument that makes visible emissions that may otherwise be invisible to the naked eye. (5...

40 CFR 63.11 - Control device and work practice requirements.

Science.gov (United States)

2010-07-01

... making visible emissions that may otherwise be invisible to the naked eye. (4) Optical gas imaging instrument means an instrument that makes visible emissions that may otherwise be invisible to the naked eye...) Flares shall be designed for and operated with no visible emissions, except for periods not to exceed a...