Beta-Defensin-2 and Beta-Defensin-3 Reduce Intestinal Damage Caused by Salmonella typhimurium Modulating the Expression of Cytokines and Enhancing the Probiotic Activity of Enterococcus faecium

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Alessandra Fusco

2017-01-01

Full Text Available The intestinal microbiota is a major factor in human health and disease. This microbial community includes autochthonous (permanent inhabitants and allochthonous (transient inhabitants microorganisms that contribute to maintaining the integrity of the intestinal wall, modulating responses to pathogenic noxae and representing a key factor in the maturation of the immune system. If this healthy microbiota is disrupted by antibiotics, chemotherapy, or a change in diet, intestinal colonization by pathogenic bacteria or viruses may occur, leading to disease. To manage substantial microbial exposure, epithelial surfaces of the intestinal tract produce a diverse arsenal of antimicrobial peptides (AMPs, including, of considerable importance, the β-defensins, which directly kill or inhibit the growth of microorganisms. Based on the literature data, the purpose of this work was to create a line of intestinal epithelial cells able to stably express gene encoding human β-defensin-2 (hBD-2 and human β-defensin-3 (hBD-3, in order to test their role in S. typhimurium infections and their interaction with the bacteria of the gut microbiota.

Acyclic models

CERN Document Server

Barr, Michael

2002-01-01

Acyclic models is a method heavily used to analyze and compare various homology and cohomology theories appearing in topology and algebra. This book is the first attempt to put together in a concise form this important technique and to include all the necessary background. It presents a brief introduction to category theory and homological algebra. The author then gives the background of the theory of differential modules and chain complexes over an abelian category to state the main acyclic models theorem, generalizing and systemizing the earlier material. This is then applied to various cohomology theories in algebra and topology. The volume could be used as a text for a course that combines homological algebra and algebraic topology. Required background includes a standard course in abstract algebra and some knowledge of topology. The volume contains many exercises. It is also suitable as a reference work for researchers.

Proteinase 3 carries small unusual carbohydrates and associates with αlpha-defensins

DEFF Research Database (Denmark)

Zoega, Morten; Ravnsborg, Tina; Højrup, Peter

2012-01-01

with carbohydrates at Asn 102 and 147 carrying unusual small moieties indicating heavy processing. Mass spectrometric analysis and immuno blotting revealed strong association of highly purified PR3 with α-defensins and oligomers hereof. Irreversible inhibition of PR3 by α1-antitrypsin did not affect its association...

Antiplasmodial activity is an ancient and conserved feature of tick defensins

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Alejandro Cabezas-Cruz

2016-10-01

Full Text Available Ancestral sequence reconstruction has been widely used to test evolution-based hypotheses. The genome of the European tick vector, Ixodes ricinus, encodes for defensin peptides with diverse antimicrobial activities against distantly related pathogens. These pathogens include fungi, Gram-negative and Gram-positive bacteria, i.e., a wide antimicrobial spectrum. Ticks do not transmit these pathogens, suggesting that these defensins may act against a wide range of microbes encountered by ticks during blood feeding or off-host periods. As demonstrated here, these I. ricinus defensins are also effective against the apicomplexan parasite Plasmodium falciparum. To study the general evolution of antimicrobial activity in tick defensins, the ancestral amino acid sequence of chelicerate defensins, which existed approximately 444 million years ago, was reconstructed using publicly available scorpion and tick defensin sequences (named Scorpions-Ticks Defensins Ancestor, STiDA. The activity of STiDA was tested against P. falciparum and the same Gram-negative and Gram-positive bacteria that were used for the I. ricinus defensins. While some extant tick defensins exhibit a wide antimicrobial spectrum, the ancestral defensin showed moderate activity against one of the tested microbes, P. falciparum. This study suggests that amino acid variability and defensin family expansion increased the antimicrobial spectrum of ancestral tick defensins.

Partial characterization of three β-defensin gene transcripts in river ...

African Journals Online (AJOL)

In this study, the tracheal tissues from Egyptian river buffalo and cattle were screened for the presence of three bovine β-defensin gene transcripts. Three primer pairs were designed on the basis of published Bos taurus sequences for partial amplification of β-defensin 4, β-defensin 10 and β-defensin 11 complementary DNA ...

Acyclicity in edge-colored graphs

DEFF Research Database (Denmark)

Gutin, Gregory; Jones, Mark; Sheng, Bin

2017-01-01

A walk W in edge-colored graphs is called properly colored (PC) if every pair of consecutive edges in W is of different color. We introduce and study five types of PC acyclicity in edge-colored graphs such that graphs of PC acyclicity of type i is a proper superset of graphs of acyclicity of type i......+1, i=1,2,3,4. The first three types are equivalent to the absence of PC cycles, PC closed trails, and PC closed walks, respectively. While graphs of types 1, 2 and 3 can be recognized in polynomial time, the problem of recognizing graphs of type 4 is, somewhat surprisingly, NP-hard even for 2-edge-colored...... graphs (i.e., when only two colors are used). The same problem with respect to type 5 is polynomial-time solvable for all edge-colored graphs. Using the five types, we investigate the border between intractability and tractability for the problems of finding the maximum number of internally vertex...

Outstanding effects on antithrombin activity of modified TBA diastereomers containing an optically pure acyclic nucleotide analogue.

Science.gov (United States)

Scuotto, M; Persico, M; Bucci, M; Vellecco, V; Borbone, N; Morelli, E; Oliviero, G; Novellino, E; Piccialli, G; Cirino, G; Varra, M; Fattorusso, C; Mayol, L

2014-07-28

Herein, we report optically pure modified acyclic nucleosides as ideal probes for aptamer modification. These new monomers offer unique advantages in exploring the role played in thrombin inhibition by a single residue modification at key positions of the TBA structure.

Defensins: The Case for Their Use against Mycobacterial Infections

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Haodi Dong

2016-01-01

Full Text Available Human tuberculosis remains a huge global public health problem with an estimated 1/3rd of the population being infected. Defensins are antibacterial cationic peptides produced by a number of cell types, most notably neutrophil granulocytes and epithelial cells. All three defensin types (α-, β-, and θ-defensins have antibacterial activities, mainly through bacterial membrane permeabilization. Defensins are effective against Gram-negative and Gram-positive bacteria including mycobacteria and are active both intra- and extracellularly. Mycobacterial resistance has never been demonstrated although the mprF gene encoding resistance in Staphylococcus aureus is present in the Mycobacterium tuberculosis genome. In addition to their antibacterial effect, defensins are chemoattractants for macrophages and neutrophils. There are many cases for their use for therapy or prophylaxis in tuberculosis as well. In conclusion, we propose that there is considerable scope and potential for exploring their use as therapeutic/prophylactic agents and more comprehensive survey of defensins from different species and their bioactivity is timely.

Two novel antimicrobial defensins from rice identified by gene coexpression network analyses.

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Tantong, Supaluk; Pringsulaka, Onanong; Weerawanich, Kamonwan; Meeprasert, Arthitaya; Rungrotmongkol, Thanyada; Sarnthima, Rakrudee; Roytrakul, Sittiruk; Sirikantaramas, Supaart

2016-10-01

Defensins form an antimicrobial peptides (AMP) family, and have been widely studied in various plants because of their considerable inhibitory functions. However, their roles in rice (Oryza sativa L.) have not been characterized, even though rice is one of the most important staple crops that is susceptible to damaging infections. Additionally, a previous study identified 598 rice genes encoding cysteine-rich peptides, suggesting there are several uncharacterized AMPs in rice. We performed in silico gene expression and coexpression network analyses of all genes encoding defensin and defensin-like peptides, and determined that OsDEF7 and OsDEF8 are coexpressed with pathogen-responsive genes. Recombinant OsDEF7 and OsDEF8 could form homodimers. They inhibited the growth of the bacteria Xanthomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, and Erwinia carotovora subsp. atroseptica with minimum inhibitory concentration (MIC) ranging from 0.6 to 63μg/mL. However, these OsDEFs are weakly active against the phytopathogenic fungi Helminthosporium oryzae and Fusarium oxysporum f.sp. cubense. This study describes a useful method for identifying potential plant AMPs with biological activities. Copyright © 2016 Elsevier Inc. All rights reserved.

Oil Palm Defensin: A Thermal Stable Peptide that Restricts the Mycelial Growth of Ganoderma boninense.

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Tan, Yung-Chie; Ang, Cheng-Liang; Wong, Mui-Yun; Ho, Chai-Ling

2016-01-01

Plant defensins are plant defence peptides that have many different biological activities, including antifungal, antimicrobial, and insecticidal activities. A cDNA (EgDFS) encoding defensin was isolated from Elaeis guineensis. The open reading frame of EgDFS contained 231 nucleotides encoding a 71-amino acid protein with a predicted molecular weight at 8.69 kDa, and a potential signal peptide. The eight highly conserved cysteine sites in plant defensins were also conserved in EgDFS. The EgDFS sequence lacking 30 amino acid residues at its N-terminus (EgDFSm) was cloned into Escherichia coli BL21 (DE3) pLysS and successfully expressed as a soluble recombinant protein. The recombinant EgDFSm was found to be a thermal stable peptide which demonstrated inhibitory activity against the growth of G. boninense possibly by inhibiting starch assimilation. The role of EgDFSm in oil palm defence system against the infection of pathogen G. boninense was discussed.

Petunia floral defensins with unique prodomains as novel candidates for development of fusarium wilt resistance in transgenic banana plants.

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Siddhesh B Ghag

Full Text Available Antimicrobial peptides are a potent group of defense active molecules that have been utilized in developing resistance against a multitude of plant pathogens. Floral defensins constitute a group of cysteine-rich peptides showing potent growth inhibition of pathogenic filamentous fungi especially Fusarium oxysporum in vitro. Full length genes coding for two Petunia floral defensins, PhDef1 and PhDef2 having unique C-terminal 31 and 27 amino acid long predicted prodomains, were overexpressed in transgenic banana plants using embryogenic cells as explants for Agrobacterium-mediated genetic transformation. High level constitutive expression of these defensins in elite banana cv. Rasthali led to significant resistance against infection of Fusarium oxysporum f. sp. cubense as shown by in vitro and ex vivo bioassay studies. Transgenic banana lines expressing either of the two defensins were clearly less chlorotic and had significantly less infestation and discoloration in the vital corm region of the plant as compared to untransformed controls. Transgenic banana plants expressing high level of full-length PhDef1 and PhDef2 were phenotypically normal and no stunting was observed. In conclusion, our results suggest that high-level constitutive expression of floral defensins having distinctive prodomains is an efficient strategy for development of fungal resistance in economically important fruit crops like banana.

An anionic defensin from Plutella xylostella with potential activity against Bacillus thuringiensis.

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Xu, X-X; Zhang, Y-Q; Freed, S; Yu, J; Gao, Y-F; Wang, S; Ouyang, L-N; Ju, W-Y; Jin, F-L

2016-12-01

Insect defensins, are cationic peptides that play an important role in immunity against microbial infection. In the present study, an anionic defensin from Plutella xylostella, (designated as PxDef) was first cloned and characterized. Amino acid sequence analysis showed that the mature peptide owned characteristic six-cysteine motifs with predicted isoelectric point of 5.57, indicating an anionic defensin. Quantitative real-time polymerase chain reaction analysis showed that PxDef was significantly induced in epidermis, fat body, midgut and hemocytes after injection of heat-inactivated Bacillus thuringiensis, while such an induction was delayed by the injection of live B. thuringiensis in the 4th instar larvae of P. xylostella. Knocking down the expression of nuclear transcription factor Dorsal in P. xylostella by RNA interference significantly decreased the mRNA level of PxDef, and increased the sensitivity of P. xylostella larvae to the infection by live B. thuringiensis. The purified recombinant mature peptide (PxDef) showed higher activity against Gram-positive bacteria, with the minimum inhibition concentrations of 1.6 and 2.6 µM against B. thuringiensis and Bacillus subtilis, respectively. To our knowledge, this is the first report about an anionic PxDef, which may play an important role in the immune system of P. xylostella against B. thuringiensis.

Inhibition of hypoxanthine-guanine phosphoribosyltransferase by acyclic nucleoside phosphonates: A new class of antimalarial therapeutics

Czech Academy of Sciences Publication Activity Database

Keough, D. T.; Hocková, Dana; Holý, Antonín; Naesens, L.; Skinner-Adams, T. S.; de Jersey, J.; Guddat, L. W.

2009-01-01

Roč. 52, č. 14 (2009), s. 4391-4399 ISSN 0022-2623 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * phosphoribosyltransferase * enzyme inhibitors * Plasmodium falciparum Subject RIV: CC - Organic Chemistry Impact factor: 4.802, year: 2009

α-Defensins and outcome in patients with chronic heart failure

DEFF Research Database (Denmark)

Christensen, Heidi M; Frystyk, Jan; Faber, Jens

2012-01-01

Aim a-Defensins are part of the innate immune system. Low-grade inflammation seems to play a crucial role in development and progression of chronic heart failure (CHF). The aims of the present study were to compare plasma levels of a-defensins in CHF patients and healthy controls and to examine......% confidence interval 1.19-2.28, P = 0.002) per 1 standard deviation increment in Ln (natural logarithm)-transformed a-defensin values. The combination of high a-defensins and NT-proBNP levels provided incremental prognostic information independent of well-known prognostic biomarkers in heart failure...... in 194 CHF patients, and compared plasma levels with those of 98 age-matched healthy controls. a-Defensin levels were twice as high among CHF patients in New York Heart Association (NYHA) functional class III-IV than in patients in NYHA class I-II and healthy controls (P = 0.001). The absolute increase...

Characterization of defensin gene from abalone Haliotis discus hannai and its deduced protein

Science.gov (United States)

Hong, Xuguang; Sun, Xiuqin; Zheng, Minggang; Qu, Lingyun; Zan, Jindong; Zhang, Jinxing

2008-11-01

Defensin is one of preserved ancient host defensive materials formed in biological evolution. As a regulator and effector molecule, it is very important in animals’ acquired immune system. This paper reports the defensin gene from the mixed liver and kidney cDNA library of abalone Haliotis discus hannai Ino. Sequence analysis shows that the gene sequence of full-length cDNA encodes 42 mature peptides (including six Cys), molecular weight of 4 323 Da, and pI of 8.02. Amino acid sequence homology analysis shows that the peptides are highly similar (70% in common) to other insects defensin. Because of a typical insect-defensin structural character of mature peptide in the secondary structure, the polypeptide named Haliotis discus defensin (hd-def), a novel of antimicrobial peptides, belongs to insects defensin subfamily. The RT-PCR result of Haliotis discus defensin shows that the gene can be expressed only in the hepatopancreas by Gram-negative and positive bacteria stimulation, which is ascribed to inducible expression. Therefore, it is revealed that the Haliotis discus defensin gene expression was related to the antibacterial infection of Haliotis discus hannai Ino.

The Fungal Defensin Family Enlarged

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Jiajia Wu

2014-08-01

Full Text Available Fungi are an emerging source of peptide antibiotics. With the availability of a large number of model fungal genome sequences, we can expect that more and more fungal defensin-like peptides (fDLPs will be discovered by sequence similarity search. Here, we report a total of 69 new fDLPs encoded by 63 genes, in which a group of fDLPs derived from dermatophytes are defined as a new family (fDEF8 according to sequence and phylogenetic analyses. In the oleaginous fungus Mortierella alpine, fDLPs have undergone extensive gene expansion. Our work further enlarges the fungal defensin family and will help characterize new peptide antibiotics with therapeutic potential.

An Algorithm for Determining Minimal Reduced—Coverings of Acyclic Database Schemes

Institute of Scientific and Technical Information of China (English)

刘铁英; 叶新铭

1996-01-01

This paper reports an algoritm(DTV)for deermining the minimal reducedcovering of an acyclic database scheme over a specified subset of attributes.The output of this algotithm contains not only minimum number of attributes but also minimum number of partial relation schemes.The algorithm has complexity O(|N|·|E|2),where|N| is the number of attributes and |E|the number of relation schemes.It is also proved that for Berge,γ or β acyclic database schemes,the output of algorithm DTV maintains the acyclicity correspondence.

Bacterial feeding, Leishmania infection and distinct infection routes induce differential defensin expression in Lutzomyia longipalpis.

Science.gov (United States)

Telleria, Erich L; Sant'Anna, Maurício R Viana; Alkurbi, Mohammad O; Pitaluga, André N; Dillon, Rod J; Traub-Csekö, Yara M

2013-01-11

Phlebotomine insects harbor bacterial, viral and parasitic pathogens that can cause diseases of public health importance. Lutzomyia longipalpis is the main vector of visceral leishmaniasis in the New World. Insects can mount a powerful innate immune response to pathogens. Defensin peptides take part in this response and are known to be active against Gram-positive and Gram-negative bacteria, and some parasites. We studied the expression of a defensin gene from Lutzomyia longipalpis to understand its role in sand fly immune response. We identified, sequenced and evaluated the expression of a L. longipalpis defensin gene by semi-quantitative RT-PCR. The gene sequence was compared to other vectors defensins and expression was determined along developmental stages and after exposure of adult female L. longipalpis to bacteria and Leishmania. Phylogenetic analysis showed that the L. longipalpis defensin is closely related to a defensin from the Old World sand fly Phlebotomus duboscqi. Expression was high in late L4 larvae and pupae in comparison to early larval stages and newly emerged flies. Defensin expression was modulated by oral infection with bacteria. The Gram-positive Micrococcus luteus induced early high defensin expression, whilst the Gram-negative entomopathogenic Serratia marcescens induced a later response. Bacterial injection also induced defensin expression in adult insects. Female sand flies infected orally with Leishmania mexicana showed no significant difference in defensin expression compared to blood fed insects apart from a lower defensin expression 5 days post Leishmania infection. When Leishmania was introduced into the hemolymph by injection there was no induction of defensin expression until 72 h later. Our results suggest that L. longipalpis modulates defensin expression upon bacterial and Leishmania infection, with patterns of expression that are distinct among bacterial species and routes of infection.

Antibacterial activity of defensin PaDef from avocado fruit (Persea americana var. drymifolia) expressed in endothelial cells against Escherichia coli and Staphylococcus aureus.

Science.gov (United States)

Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Suárez-Rodríguez, Luis M; Salgado-Garciglia, Rafael; Rodríguez-Zapata, Luis C; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

2013-01-01

Antimicrobial therapy is a useful tool to control infectious diseases in general and rising antibiotic resistant microorganisms in particular. Alternative strategies are desirable, and antimicrobial peptides (AMP) represent attractive control agents. Mexican avocado (Persea americana var. drymifolia) is used in traditional medicine; however, the AMP production has not been reported in this plant. We obtained a cDNA library from avocado fruit and clone PaDef was identified, which has a cDNA (249 bp) encoding a protein (78 aa) homologous with plant defensins (>80%). We expressed the defensin PaDef cDNA (pBME3) in the bovine endothelial cell line BVE-E6E7. Polyclonal and clonal populations were obtained and their activity was evaluated against Escherichia coli, Staphylococcus aureus, and Candida albicans. E. coli viability was inhibited with 100 μg/mL of total protein from clones (>55%). Also, S. aureus viability was inhibited from 50 μg/mL total protein (27-38%) but was more evident at 100 μg/mL (52-65%). This inhibition was higher than the effect showed by polyclonal population (~23%). Finally, we did not detect activity against C. albicans. These results are the first report that shows antimicrobial activity of a defensin produced by avocado and suggest that this AMP could be used in the control of pathogens.

Antibacterial Activity of Defensin PaDef from Avocado Fruit (Persea americana var. drymifolia Expressed in Endothelial Cells against Escherichia coli and Staphylococcus aureus

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Jaquelina Julia Guzmán-Rodríguez

2013-01-01

Full Text Available Antimicrobial therapy is a useful tool to control infectious diseases in general and rising antibiotic resistant microorganisms in particular. Alternative strategies are desirable, and antimicrobial peptides (AMP represent attractive control agents. Mexican avocado (Persea americana var. drymifolia is used in traditional medicine; however, the AMP production has not been reported in this plant. We obtained a cDNA library from avocado fruit and clone PaDef was identified, which has a cDNA (249 bp encoding a protein (78 aa homologous with plant defensins (>80%. We expressed the defensin PaDef cDNA (pBME3 in the bovine endothelial cell line BVE-E6E7. Polyclonal and clonal populations were obtained and their activity was evaluated against Escherichia coli, Staphylococcus aureus, and Candida albicans. E. coli viability was inhibited with 100 μg/mL of total protein from clones (>55%. Also, S. aureus viability was inhibited from 50 μg/mL total protein (27–38% but was more evident at 100 μg/mL (52–65%. This inhibition was higher than the effect showed by polyclonal population (~23%. Finally, we did not detect activity against C. albicans. These results are the first report that shows antimicrobial activity of a defensin produced by avocado and suggest that this AMP could be used in the control of pathogens.

Rabbit defensin (NP-1) genetic engineering of plant | Ting | African ...

African Journals Online (AJOL)

Rabbit defensin (NP-1) genetic engineering of plant. ... Log in or Register to get access to full text downloads. ... defensin genetic engineering of plant in recent years, and also focuses on the existing problems and new strategies in this area.

Enteric alpha defensins in norm and pathology

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Lisitsyn Nikolai A

2012-01-01

Full Text Available Abstract Microbes living in the mammalian gut exist in constant contact with immunity system that prevents infection and maintains homeostasis. Enteric alpha defensins play an important role in regulation of bacterial colonization of the gut, as well as in activation of pro- and anti-inflammatory responses of the adaptive immune system cells in lamina propria. This review summarizes currently available data on functions of mammalian enteric alpha defensins in the immune defense and changes in their secretion in intestinal inflammatory diseases and cancer.

Directional and balancing selection in human beta-defensins.

Science.gov (United States)

Hollox, Edward J; Armour, John A L

2008-04-16

In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93), is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

Purification, cDNA cloning and modification of a defensin from the coconut rhinoceros beetle, Oryctes rhinoceros.

Science.gov (United States)

Ishibashi, J; Saido-Sakanaka, H; Yang, J; Sagisaka, A; Yamakawa, M

1999-12-01

A novel member of the insect defensins, a family of antibacterial peptides, was purified from larvae of the coconut rhinoceros beetle, Oryctes rhinoceros, immunized with Escherichia coli. A full-size cDNA was cloned by combining reverse-transcription PCR (RT-PCR), and 5'- and 3'-rapid amplification of cDNA ends (RACE). Analysis of the O. rhinoceros defensin gene expression showed it to be expressed in the fat body and hemocyte, midgut and Malpighian tubules. O. rhinoceros defensin showed strong antibacterial activity against Staphylococcus aureus. A 9-mer peptide amidated at its C-terminus, AHCLAICRK-NH2 (Ala22-Lys30-NH2), was synthesized based on the deduced amino-acid sequence, assumed to be an active site sequence by analogy with the sequence of a defensin isolated from larvae of the beetle Allomyrina dichotoma. This peptide showed antibacterial activity against S. aureus, methicillin-resistant S. aureus, E. coli and Pseudomonas aeruginosa. We further modified this oligopeptide and synthesized five 9-mer peptides, ALRLAIRKR-NH2, ALLLAIRKR-NH2, AWLLAIRKR-NH2, ALYLAIRKR-NH2 and ALWLAIRKR-NH2. These oligopeptides showed strong antibacterial activity against Gram-negative and Gram-positive bacteria. The antibacterial effect of Ala22-Lys30-NH2 analogues was due to its interaction with bacterial membranes, judging from the leakage of liposome-entrapped glucose. These Ala22-Lys30-NH2 analogues did not show haemolytic activity and did not inhibit the growth of murine fibroblast cells or macrophages, except for AWLLAIRKR-NH2.

The cold-induced defensin TAD1 confers resistance against snow mold and Fusarium head blight in transgenic wheat.

Science.gov (United States)

Sasaki, Kentaro; Kuwabara, Chikako; Umeki, Natsuki; Fujioka, Mari; Saburi, Wataru; Matsui, Hirokazu; Abe, Fumitaka; Imai, Ryozo

2016-06-20

TAD1 (Triticum aestivum defensin 1) is induced during cold acclimation in winter wheat and encodes a plant defensin with antimicrobial activity. In this study, we demonstrated that recombinant TAD1 protein inhibits hyphal growth of the snow mold fungus, Typhula ishikariensis in vitro. Transgenic wheat plants overexpressing TAD1 were created and tested for resistance against T. ishikariensis. Leaf inoculation assays revealed that overexpression of TAD1 confers resistance against the snow mold. In addition, the TAD1-overexpressors showed resistance against Fusarium graminearum, which causes Fusarium head blight, a devastating disease in wheat and barley. These results indicate that TAD1 is a candidate gene to improve resistance against multiple fungal diseases in cereal crops. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification, cloning and functional characterization of novel beta-defensins in the rat (Rattus norvegicus

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French Frank S

2006-02-01

Full Text Available Abstract Background beta-defensins are small cationic peptides that exhibit broad spectrum antimicrobial properties. The majority of beta-defensins identified in humans are predominantly expressed in the male reproductive tract and have roles in non-immunological processes such as sperm maturation and capacitation. Characterization of novel defensins in the male reproductive tract can lead to increased understanding of their dual roles in immunity and sperm maturation. Methods In silico rat genomic analyses were used to identify novel beta-defensins related to human defensins 118–123. RNAs isolated from male reproductive tract tissues of rat were reverse transcribed and PCR amplified using gene specific primers for defensins. PCR products were sequenced to confirm their identity. RT-PCR analysis was performed to analyze the tissue distribution, developmental expression and androgen regulation of these defensins. Recombinant defensins were tested against E. coli in a colony forming unit assay to analyze their antimicrobial activities. Results Novel beta-defensins, Defb21, Defb24, Defb27, Defb30 and Defb36 were identified in the rat male reproductive tract. Defb30 and Defb36 were the most restricted in expression, whereas the others were expressed in a variety of tissues including the female reproductive tract. Early onset of defensin expression was observed in the epididymides of 10–60 day old rats. Defb21-Defb36 expression in castrated rats was down regulated and maintained at normal levels in testosterone supplemented animals. DEFB24 and DEFB30 proteins showed potent dose and time dependent antibacterial activity. Conclusion Rat Defb21, Defb24, Defb27, Defb30 and Defb36 are abundantly expressed in the male reproductive tract where they most likely protect against microbial invasion. They are developmentally regulated and androgen is required for full expression in the adult epididymis.

Inflammatory disorders mimicking periprosthetic joint infections may result in false positive α-defensin.

Science.gov (United States)

Plate, Andreas; Stadler, Laura; Sutter, Reto; Anagnostopoulos, Alexia; Frustaci, Dario; Zbinden, Reinhard; Fucentese, Sandro F; Zinkernagel, Annelies S; Zingg, Patrick O; Achermann, Yvonne

2018-02-26

The antimicrobial peptide α-defensin has recently been introduced as potential "single" biomarker with a high sensitivity and specificity for the preoperative diagnosis of periprosthetic joint infections (PJIs). However, most studies assessed the benefits of the test with exclusion of patients with rheumatic diseases. We aimed to evaluate the α-defensin test in a cohort study without exclusion of cases with inflammatory diseases. Between June 2016 and June 2017, we prospectively included cases with a suspected PJI and an available lateral flow test α-defensin (Synovasure®) in synovial fluid. We compared the test result to the diagnostic criteria for PJIs published by an International Consensus Group in 2013. We included 109 cases (49 hips, 60 knees) in which preoperative α-defensin tests had been performed. Thereof, 20 PJIs (16 hips, 4 knees) were diagnosed. Preoperative α-defensin tests were positive in 25 cases (22.9%) with a test sensitivity and specificity of 90% and 92.1% (95% confidence interval [CI], 68.3 - 98.8% and 84.5 - 96.8%, respectively), and a high negative predictive value of 97.6% (95% CI, 91.7 - 99.4%). We interpreted seven α-defensin tests as false positive, mainly in cases with inflammatory rheumatic diseases, including crystal deposition diseases. A negative synovial α-defensin test can reliably rule out a PJI. However, the test can be false positive in conjunction with an underlying non-infectious inflammatory disease. We therefore propose to use the α-defensin test only in addition to MSIS criteria and assessment for crystals in synovial aspirates. Copyright © 2018. Published by Elsevier Ltd.

α-Defensins Induce a Post-translational Modification of Low Density Lipoprotein (LDL) That Promotes Atherosclerosis at Normal Levels of Plasma Cholesterol.

Science.gov (United States)

Abu-Fanne, Rami; Maraga, Emad; Abd-Elrahman, Ihab; Hankin, Aviel; Blum, Galia; Abdeen, Suhair; Hijazi, Nuha; Cines, Douglas B; Higazi, Abd Al-Roof

2016-02-05

Approximately one-half of the patients who develop clinical atherosclerosis have normal or only modest elevations in plasma lipids, indicating that additional mechanisms contribute to pathogenesis. In view of increasing evidence that inflammation contributes to atherogenesis, we studied the effect of human neutrophil α-defensins on low density lipoprotein (LDL) trafficking, metabolism, vascular deposition, and atherogenesis using transgenic mice expressing human α-defensins in their polymorphonuclear leukocytes (Def(+/+)). Accelerated Def(+/+) mice developed α-defensin·LDL complexes that accelerate the clearance of LDL from the circulation accompanied by enhanced vascular deposition and retention of LDL, induction of endothelial cathepsins, increased endothelial permeability to LDL, and the development of lipid streaks in the aortic roots when fed a regular diet and at normal plasma levels of LDL. Transplantation of bone marrow from Def(+/+) to WT mice increased LDL clearance, increased vascular permeability, and increased vascular deposition of LDL, whereas transplantation of WT bone marrow to Def(+/+) mice prevented these outcomes. The same outcome was obtained by treating Def(+/+) mice with colchicine to inhibit the release of α-defensins. These studies identify a potential new link between inflammation and the development of atherosclerosis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

3000 Horsepower super conductive field acyclic motor

International Nuclear Information System (INIS)

Marshall, R.

1983-01-01

A 3000 hp acyclic motor was assembled and tested utilizing superconducting field coils. The magnet assembly is designed as a quadrupole magnet, utilizing a multifilamentary niobium titanium superconductor. Each magnet coil is 18 inches in diameter and 10 inches long, and operates at rated current of 200 amperes, providing 5.8 tesla in the bore of the coils in the motor configuration. The average winding current density is 10,600 A/cm 2 . The acyclic motor is of a drum-type design with liquid metal current collectors, and is designed to model full-scale machinery for ship propulsion applications. Laboratory test data verified the electrical and electromagnetic design to be within three percent of the calculated values

Directional and balancing selection in human beta-defensins

Directory of Open Access Journals (Sweden)

Armour John AL

2008-04-01

Full Text Available Abstract Background In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. Results We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93, is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Conclusion Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

A crucial role of paralogous β-defensin genes in the Chinese alligator innate immune system revealed by the first determination of a Crocodilia defensin cluster.

Science.gov (United States)

Tang, Ke-Yi; Wang, Xin; Wan, Qiu-Hong; Fang, Sheng-Guo

2018-04-01

The β-defensin, one of the antimicrobial peptides (AMPs), is a significant component of the innate immune with a broad range of antimicrobial activities. Differing from the widely-studied mammals and birds, limited information about β-defensins has been reported in reptiles, especially in crocodilians. As a same ancient species as dinosaurs and the most endangered species of 23 crocodilians, the survival of Chinese alligator (Alligator sinensis) means a powerful immune system and possible involvement of AMPs in its immune resistance. In this study, we identified 20 novel Alligator sinensisβ-defensin genes (AsBDs) from a 390 kb region using bioinformatic and experimental approaches, and successfully distinguished six orthologous AsBDs to birds and nine paralogous AsBDs undergoing gene duplication events. The amino acid alignment shows that the AsBD paralogs, like α-defensins, encode a significantly longer pro-piece comparing with the orthologs. The calculation of non-synonymous (d N ) and synonymous (d S ) substitutions in the mature peptide reveals that the AsBD paralogs experience a significantly higher selective pressure (d N /d S ) than the orthologs, but a similar evolutionary force to α-defensins. The gene expression result indicates that the AsBD paralogs have a significantly higher expression level than the orthologos in gastrointestinal tract where the host is vulnerable to enteric pathogenic bacteria, as observed in α-defensins. These three pieces of evidence demonstrate that the AsBD paralogs do play an important role in maintaining long-term survival of this endangered reptile. Thus, this survey of AsBDs on the genomic structure, evolutionary characteristics, and expression pattern provides a genetic and immunological foundation for further investigating their antimicrobial function and alternative antibiotics potentiality. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Characterization of Cimex lectularius (bedbug) defensin peptide and its antimicrobial activity against human skin microflora.

Science.gov (United States)

Kaushal, Akanksha; Gupta, Kajal; van Hoek, Monique L

2016-02-19

Antimicrobial peptides are components of both vertebrate and invertebrate innate immune systems that are expressed in response to exposure to bacterial antigens. Naturally occurring antimicrobial peptides from evolutionarily ancient species have been extensively studied and are being developed as potential therapeutics against antibiotic resistant microorganisms. In this study, a putative Cimex lectularius (bedbug, CL) defensin is characterized for its effectiveness against human skin flora including Gram-negative and Gram-positive bacteria. The bedbug defensin (CL-defensin), belonging to family of insect defensins, is predicted to have a characteristic N-terminal loop, an α-helix, and an antiparallel β-sheet, which was supported by circular dichroism spectroscopy. The defensin was shown to be antimicrobial against Gram-positive bacteria commonly found on human skin (Micrococcus luteus, Corynebacterium renale, Staphylococcus aureus and Staphylococcus epidermidis); however, it was ineffective against common skin Gram-negative bacteria (Pseudomonas aeruginosa and Acinetobacter baumannii) under low-salt conditions. CL-defensin was also effective against M. luteus and C. renale in high-salt (MIC) conditions. Our studies indicate that CL-defensin functions by depolarization and pore-formation in the bacterial cytoplasmic membrane. Copyright © 2016 Elsevier Inc. All rights reserved.

Contribution of alpha- and beta-defensins to lung function decline and infection in smokers: an association study

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Anthonisen Nicholas R

2006-05-01

Full Text Available Abstract Background Alpha-defensins, which are major constituents of neutrophil azurophilic granules, and beta-defensins, which are expressed in airway epithelial cells, could contribute to the pathogenesis of chronic obstructive pulmonary disease by amplifying cigarette smoke-induced and infection-induced inflammatory reactions leading to lung injury. In Japanese and Chinese populations, two different beta-defensin-1 polymorphisms have been associated with chronic obstructive pulmonary disease phenotypes. We conducted population-based association studies to test whether alpha-defensin and beta-defensin polymorphisms influenced smokers' susceptibility to lung function decline and susceptibility to lower respiratory infection in two groups of white participants in the Lung Health Study (275 = fast decline in lung function and 304 = no decline in lung function. Methods Subjects were genotyped for the alpha-defensin-1/alpha-defensin-3 copy number polymorphism and four beta-defensin-1 polymorphisms (G-20A, C-44G, G-52A and Val38Ile. Results There were no associations between individual polymorphisms or imputed haplotypes and rate of decline in lung function or susceptibility to infection. Conclusion These findings suggest that, in a white population, the defensin polymorphisms tested may not be of importance in determining who develops abnormally rapid lung function decline or is susceptible to developing lower respiratory infections.

Conformational landscape and pathway of disulfide bond reduction of human alpha defensin

NARCIS (Netherlands)

Snijder, Joost; Van De Waterbeemd, Michiel; Glover, Matthew S.; Shi, Liuqing; Clemmer, David E.; Heck, Albert J R

2015-01-01

Human alpha defensins are a class of antimicrobial peptides with additional antiviral activity. Such antimicrobial peptides constitute a major part of mammalian innate immunity. Alpha defensins contain six cysteines, which form three well defined disulfide bridges under oxidizing conditions.

Antibacterial and antiviral roles of a fish β-defensin expressed both in pituitary and testis.

Directory of Open Access Journals (Sweden)

Jun-Yan Jin

Full Text Available Defensins are a group of cationic peptides that exhibit broad-spectrum antimicrobial activity. In this study, we cloned and characterized a β-defensin from pituitary cDNA library of a protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides. Interestingly, the β-defensin was shown to be dominantly expressed in pituitary and testis by RT-PCR and Western blot analysis, and its transcript level is significantly upregulated in reproduction organs from intersexual gonad to testis during the natural and artificial sex reversal. Promoter sequence and the responsible activity region analyses revealed the pituitary-specific POU1F1a transcription binding site and testis-specific SRY responsible site, and demonstrated that the pituitary-specific POU1F1a transcription binding site that locates between -180 and -208 bp is the major responsible region of grouper β-defensin promoter activity. Immunofluorescence localization observed its pituicyte expression in pituitary and spermatogonic cell expression in testis. Moreover, both in vitro antibacterial activity assay of the recombinant β-defensin and in vivo embryo microinjection of the β-defensin mRNA were shown to be effective in killing gram-negative bacteria. And, its antiviral role was also demonstrated in EPC cells transfected with the β-defensin construct. Additionally, the antibacterial activity was sensitive to concentrations of Na(+, K(+, Ca(2+ and Mg(2+. The above intriguing findings strongly suggest that the fish β-defensin might play significant roles in both innate immunity defense and reproduction endocrine regulation.

Antibacterial and antiviral roles of a fish β-defensin expressed both in pituitary and testis.

Science.gov (United States)

Jin, Jun-Yan; Zhou, Li; Wang, Yang; Li, Zhi; Zhao, Jiu-Gang; Zhang, Qi-Ya; Gui, Jian-Fang

2010-12-20

Defensins are a group of cationic peptides that exhibit broad-spectrum antimicrobial activity. In this study, we cloned and characterized a β-defensin from pituitary cDNA library of a protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides). Interestingly, the β-defensin was shown to be dominantly expressed in pituitary and testis by RT-PCR and Western blot analysis, and its transcript level is significantly upregulated in reproduction organs from intersexual gonad to testis during the natural and artificial sex reversal. Promoter sequence and the responsible activity region analyses revealed the pituitary-specific POU1F1a transcription binding site and testis-specific SRY responsible site, and demonstrated that the pituitary-specific POU1F1a transcription binding site that locates between -180 and -208 bp is the major responsible region of grouper β-defensin promoter activity. Immunofluorescence localization observed its pituicyte expression in pituitary and spermatogonic cell expression in testis. Moreover, both in vitro antibacterial activity assay of the recombinant β-defensin and in vivo embryo microinjection of the β-defensin mRNA were shown to be effective in killing gram-negative bacteria. And, its antiviral role was also demonstrated in EPC cells transfected with the β-defensin construct. Additionally, the antibacterial activity was sensitive to concentrations of Na(+), K(+), Ca(2+) and Mg(2+). The above intriguing findings strongly suggest that the fish β-defensin might play significant roles in both innate immunity defense and reproduction endocrine regulation.

Plasma alpha-defensin is associated with cardiovascular morbidity and mortality in type 1 diabetic patients

DEFF Research Database (Denmark)

Joseph, G.; Tarnow, L.; Astrup, A.S.

2008-01-01

CONTEXT: alpha-Defensins are antimicrobial peptides of the innate immune system. In addition, experimental evidence suggests that alpha-defensins are proatherogenic. OBJECTIVE: The objective of the study was to examine the predictive value of plasma alpha-defensin as a clinical marker of cardiova...... to the development of CVD or an innocent bystander Udgivelsesdato: 2008/4...

Characterization of the antimicrobial peptide family defensins in the Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus), and tammar wallaby (Macropus eugenii).

Science.gov (United States)

Jones, Elizabeth A; Cheng, Yuanyuan; O'Meally, Denis; Belov, Katherine

2017-03-01

Defensins comprise a family of cysteine-rich antimicrobial peptides with important roles in innate and adaptive immune defense in vertebrates. We characterized alpha and beta defensin genes in three Australian marsupials: the Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus), and tammar wallaby (Macropus eugenii) and identified 48, 34, and 39 defensins, respectively. One hundred and twelve have the classical antimicrobial peptides characteristics required for pathogen membrane targeting, including cationic charge (between 1+ and 15+) and a high proportion of hydrophobic residues (>30%). Phylogenetic analysis shows that gene duplication has driven unique and species-specific expansions of devil, koala, and tammar wallaby beta defensins and devil alpha defensins. Defensin genes are arranged in three genomic clusters in marsupials, whereas further duplications and translocations have occurred in eutherians resulting in four and five gene clusters in mice and humans, respectively. Marsupial defensins are generally under purifying selection, particularly residues essential for defensin structural stability. Certain hydrophobic or positively charged sites, predominantly found in the defensin loop, are positively selected, which may have functional significance in defensin-target interaction and membrane insertion.

Beta-defensin genomic copy number is not a modifier locus for cystic fibrosis

Directory of Open Access Journals (Sweden)

Burgess Juliana

2005-12-01

Full Text Available Abstract Human beta-defensin 2 (DEFB4, also known as DEFB2 or hBD-2 is a salt-sensitive antimicrobial protein that is expressed in lung epithelia. Previous work has shown that it is encoded in a cluster of beta-defensin genes at 8p23.1, which varies in copy number between 2 and 12 in different individuals. We determined the copy number of this locus in 355 patients with cystic fibrosis (CF, and tested for correlation between beta-defensin cluster genomic copy number and lung disease associated with CF. No significant association was found.

Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells.

Science.gov (United States)

Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J

2017-09-01

Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.

Expression of BrD1, a plant defensin from Brassica rapa, confers resistance against brown planthopper (Nilaparvata lugens) in transgenic rices.

Science.gov (United States)

Choi, Man-Soo; Kim, Yul-Ho; Park, Hyang-Mi; Seo, Bo-Yoon; Jung, Jin-Kyo; Kim, Sun-Tae; Kim, Min-Chul; Shin, Dong-Bum; Yun, Hong-Tai; Choi, Im-Soo; Kim, Chung-Kon; Lee, Jang-Yong

2009-08-31

Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

The Alpha-defensin Test for Periprosthetic Joint Infections Is Not Affected by Prior Antibiotic Administration.

Science.gov (United States)

Shahi, Alisina; Parvizi, Javad; Kazarian, Gregory S; Higuera, Carlos; Frangiamore, Salvatore; Bingham, Joshua; Beauchamp, Christopher; Valle, Craig Della; Deirmengian, Carl

2016-07-01

Previous studies have demonstrated that the administration of antibiotics to patients before performing diagnostic testing for periprosthetic joint infection (PJI) can interfere with the accuracy of test results. Although a single-institution study has suggested that alpha-defensin maintains its concentration and sensitivity even after antibiotic treatment, this has not yet been demonstrated in a larger multiinstitutional study. (1) For the evaluation of PJI, is prior antibiotic administration associated with decreased alpha-defensin levels? (2) When prior antibiotics are given, is alpha-defensin a better screening test for PJI than the traditional tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], fluid white blood cells, fluid polymorphonuclear cells [PMNs], and fluid culture)? This retrospective study included data from 106 hip and knee arthroplasties with Musculoskeletal Infection Society-defined PJI from four centers. Of the 106 patients in this study, 30 (28%) were treated with antibiotics for PJI before diagnostic workup (ABX group), and 76 (72%) were not treated before the diagnostic workup (NO-ABX group). There were no differences in age, sex, joint, culture-negative rate, or bacteriology between groups. The patients in the ABX group had antibiotics initiated by physicians who commenced care before assessment for PJI by the treating surgeon's service. We compared the alpha-defensin levels and sensitivity between the ABX and NO-ABX groups. Additionally, the sensitivity of the alpha-defensin test was compared to that of traditional tests for PJI among patients on antibiotics. The administration of antibiotics before performing the alpha-defensin test for PJI was not associated with a decreased median alpha-defensin level (ABX group, median 4.2 [range, 1.79-12.8 S/CO] versus NO-ABX, median 4.9 [range, 0.5-16.8 S/CO], difference of medians: 0.68 S/CO [95% confidence interval {CI}, -0.98 to 1.26], p = 0.451). Furthermore, the alpha-defensin

Detecting Elusive Intermediates in Carbohydrate Conversion: A Dynamic Ensemble of Acyclic Glucose-Catalyst Complexes

DEFF Research Database (Denmark)

Meier, Sebastian; Karlsson, Magnus; Jensen, Pernille Rose

2017-01-01

within few seconds prior to reaching a steady state. Exchange between the acyclic intermediates increases at conditions that favor epimerization. Species accounting for less than 0.05% of total glucose can be monitored with sub-second time resolution to allow kinetic analysis of intermediate formation...... and catalytic conversion. Epimerization occurs 2-3 orders of magnitude-fold faster than the binding of acyclic glucose to the catalyst at near-optimum reaction conditions. The current study brings insight in to the nature of acyclic intermediate-catalyst complexes of very low population and into experimental...... strategies for characterizing very minor intermediates in carbohydrate conversion to value-added compounds....

Novel aspects of defensins' involvement in virus-induced autoimmunity in the central nervous system.

Science.gov (United States)

Kazakos, Evangelos I; Kountouras, Jannis; Polyzos, Stergios A; Deretzi, Georgia

2017-05-01

Recent research on re-circulation of interstitial fluid from the brain parenchyma to the periphery and its inferred importance in immune surveillance dysregulation are changing our conceptualization of the pathophysiology of virus-induced autoimmunity. In this context, it is necessary to reassess the immunomodulatory properties of human defensins that are variably expressed by cerebral microglia, astrocytes and choroid plexus epithelial cells and exhibit complex and often confounding roles in neuroinflammatory processes. Therefore, in this review we describe current contributions in this field and we propose novel hypotheses regarding the potential impact of defensin-related pathways on virus-driven autoimmune neurodegeneration. In this regard, we have previously proposed that abnormal expression of defensins by penetrating the blood-brain barrier (BBB) may contribute to the pathophysiology of Helicobacter pylori-related brain neurodegenerative disorders through variable modulations of innate and adaptive immune responses. We hereby propose that impaired expression of defensins by structural components of the BBB may impede glymphatic circulation and disrupt receptor signalling in pericytes that is essential for microvascular stability, thereby retaining blood-derived toxins and bystander activated T-cells in the brain and further impairing BBB integrity and hampering viral clearance. Autoreactive T-cell infiltrates in neuronaxonal lesions characteristic of chronic central nervous system diseases, such as multiple sclerosis, are directed against both, myelin and non-myelin, antigens the precise nature of which remains enigmatic. Inadequate expression of the autoimmune regulator (AIRE), a gene expressed in medullary thymic epithelial cells, induces the recruitment of defensin-specific T-cells. These cells may access the brain, thereby causing a decrease in defensin expression and subsequent down-regulation of CD91/LRP1-mediated clearance of amyloid-β that

Interaction of Defensins with Model Cell Membranes

Science.gov (United States)

Sanders, Lori K.; Schmidt, Nathan W.; Yang, Lihua; Mishra, Abhijit; Gordon, Vernita D.; Selsted, Michael E.; Wong, Gerard C. L.

2009-03-01

Antimicrobial peptides (AMPs) comprise a key component of innate immunity for a wide range of multicellular organisms. For many AMPs, activity comes from their ability to selectively disrupt and lyse bacterial cell membranes. There are a number of proposed models for this action, but the detailed molecular mechanism of selective membrane permeation remains unclear. Theta defensins are circularized peptides with a high degree of selectivity. We investigate the interaction of model bacterial and eukaryotic cell membranes with theta defensins RTD-1, BTD-7, and compare them to protegrin PG-1, a prototypical AMP, using synchrotron small angle x-ray scattering (SAXS). The relationship between membrane composition and peptide induced changes in membrane curvature and topology is examined. By comparing the membrane phase behavior induced by these different peptides we will discuss the importance of amino acid composition and placement on membrane rearrangement.

The defensin from avocado (Persea americana var. drymifolia) PaDef induces apoptosis in the human breast cancer cell line MCF-7.

Science.gov (United States)

Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Salgado-Garciglia, Rafael; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

2016-08-01

Antimicrobial peptides (AMPs) are cytotoxic to cancer cells; however, mainly the effects of AMPs from animals have been evaluated. In this work, we assessed the cytotoxicity of PaDef defensin from avocado (Persea americana var. drymifolia) on the MCF-7 cancer cell line (a breast cancer cell line) and evaluated its mechanism of action. PaDef inhibited the viability of MCF-7 cells in a concentration-dependent manner, with an IC50=141.62μg/ml. The viability of normal peripheral blood mononuclear cells was unaffected by this AMP. Additionally, PaDef induced apoptosis in MCF-7 cells in a time-dependent manner, but did not affect the membrane potential or calcium flow. In addition, PaDef IC50 induced the expression of cytochrome c, Apaf-1, and the caspase 7 and 9 genes. Likewise, this defensin induced the loss of mitochondrial Δψm and increased the phosphorylation of MAPK p38, which may lead to MCF-7 apoptosis by the intrinsic pathway. This is the first report of an avocado defensin inducing intrinsic apoptosis in cancer cells, which suggests that it could be a potential therapeutic molecule in the treatment of cancer. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Specific acyclic isoprenoids as biological markers of methanogenic bacteria in marine sediments.

Science.gov (United States)

Brassell, S C; Wardroper, A M; Thomson, I D; Maxwell, J R; Eglinton, G

1981-04-23

The widespread occurrence of extended hopanoids in sediments and petroleums illustrates the importance of bacterial lipid contributions to geological materials. In archaebacteria, however, hopanoids are absent; their role as structural components of biomembranes is fulfilled by acyclic isoprenoids. Recent studies of the lipid constituents of archaebacteria have greatly extended the range of acyclic isoprenoid skeletons known in organisms (Fig. 1). In particularly, isoprenoids with head-to-head linkages have been identified, and such compounds (for example, 3,7,11,15,18,22,26,30-octamethyldotriacontane, I) have been recognized in petroleum and as degradation products of Messel shale kerogen. Here we report the first recognition of 2,6,10,15,19-pentamethyleicosane (II), a known component of methanogens, in marine sediments of Recent to Cretaceous age (Table 1) and suggest that it and certain other acyclic isoprenoids may be used as biological markers for methanogens.

On Event Detection and Localization in Acyclic Flow Networks

KAUST Repository

Suresh, Mahima Agumbe; Stoleru, Radu; Zechman, Emily M.; Shihada, Basem

2013-01-01

Acyclic flow networks, present in many infrastructures of national importance (e.g., oil and gas and water distribution systems), have been attracting immense research interest. Existing solutions for detecting and locating attacks against

High level expression of human epithelial β-defensins (hBD-1, 2 and 3 in papillomavirus induced lesions

Directory of Open Access Journals (Sweden)

Chong Kong T

2006-09-01

Full Text Available Abstract Background Epithelial defensins including human β-defensins (hBDs and α-defensins (HDs are antimicrobial peptides that play important roles in the mucosal defense system. However, the role of defensins in papillomavirus induced epithelial lesions is unknown. Results Papilloma tissues were prospectively collected from 15 patients with recurrent respiratory papillomatosis (RRP and analyzed for defensins and chemokine IL-8 expression by quantitative, reverse-transcriptase polymerase chain reaction (RT-PCR assays. HBD-1, -2 and -3 mRNAs were detectable in papilloma samples from all RRP patients and the levels were higher than in normal oral mucosal tissues from healthy individuals. Immunohistochemical analysis showed that both hBD-1 and 2 were localized in the upper epithelial layers of papilloma tissues. Expression of hBD-2 and hBD-3 appeared to be correlated as indicated by scatter plot analysis (r = 0.837, p Conclusion Human β-defensins are upregulated in respiratory papillomas. This novel finding suggests that hBDs might contribute to innate and adaptive immune responses targeted against papillomavirus-induced epithelial lesions.

Rabbit defensin (NP-1) genetic engineering of plant

African Journals Online (AJOL)

Jane

2011-08-22

Aug 22, 2011 ... rabbit defensin has a significant toxic effect on mouse tumor cells .... Disease is one of the important factors which lead to decrease of .... Transgenic Nitrate Reductase Deficient Mutant of Chlorella ellipsoide. J. Agric.

Alpha-defensin DEFA1A3 gene copy number elevation in Danish Crohn's disease patients

DEFF Research Database (Denmark)

Jespersgaard, Cathrine; Fode, Peder; Dybdahl, Marianne

2011-01-01

BACKGROUND AND PURPOSE OF STUDY: Extensive copy number variation is observed for the DEFA1A3 gene encoding alpha-defensins 1-3. The objective of this study was to determine the involvement of alpha-defensins in colonic tissue from Crohn's disease (CD) patients and the possible genetic association...... of DEFA1A3 with CD. METHODS: Two-hundred and forty ethnic Danish CD patients were included in the study. Reverse transcriptase PCR assays determined DEFA1A3 expression in colonic tissue from a subset of patients. Immunohistochemical analysis identified alpha-defensin peptides in colonic tissue. Copy...

Biologic activities of recombinant human-beta-defensin-4 toward cultured human cancer cells.

Science.gov (United States)

Gerashchenko, O L; Zhuravel, E V; Skachkova, O V; Khranovska, N N; Filonenko, V V; Pogrebnoy, P V; Soldatkina, M A

2013-06-01

The aim of the study was in vitro analysis of biological activity of recombinant human beta-defensin-4 (rec-hBD-4). hBD-4 cDNA was cloned into pGEX-2T vector, and recombinant plasmid was transformed into E. coli BL21(DE3) cells. To purify soluble fusion GST-hBD-4 protein, affinity chromatography was applied. Rec-hBD-4 was cleaved from the fusion protein with thrombin, and purified by reverse phase chromatography on Sep-Pack C18. Effects of rec-hBD-4 on proliferation, viability, cell cycle distribution, substrate-independent growth, and mobility of cultured human cancer cells of A431, A549, and TPC-1 lines were analyzed by direct cell counting technique, MTT assay, flow cytofluorometry, colony forming assay in semi-soft medium, and wound healing assay. Rec-hBD-4 was expressed in bacterial cells as GST-hBD-4 fusion protein, and purified by routine 3-step procedure (affine chromatography on glutathione-agarose, cleavage of fusion protein by thrombin, and reverse phase chromatography). Analysis of in vitro activity of rec-hBD-4 toward three human cancer cell lines has demonstrated that the defensin is capable to affect cell behaviour in concentration-dependent manner. In 1-100 nM concentrations rec-hBD-4 significantly stimulates cancer cell proliferation and viability, and promotes cell cycle progression through G2/M checkpoint, greatly enhances colony-forming activity and mobility of the cells. Treatment of the cells with 500 nM of rec-hBD-4 resulted in opposite effects: significant suppression of cell proliferation and viability, blockage of cell cycle in G1/S checkpoint, significant inhibition of cell migration and colony forming activity. Recombinant human beta-defensin-4 is biologically active peptide capable to cause oppositely directed effects toward biologic features of cancer cells in vitro dependent on its concentration.

Alteration of the mode of antibacterial action of a defensin by the amino-terminal loop substitution

Energy Technology Data Exchange (ETDEWEB)

Gao, Bin [Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing (China); Zhu, Shunyi, E-mail: Zhusy@ioz.ac.cn [Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing (China)

2012-10-05

Highlights: Black-Right-Pointing-Pointer Al-M is an engineered fungal defensin with the n-loop of an insect defensin. Black-Right-Pointing-Pointer Al-M adopts a native defensin-like structure with high antibacterial potency. Black-Right-Pointing-Pointer Al-M kills bacteria through a membrane disruptive mechanism. Black-Right-Pointing-Pointer This work sheds light on the functional evolution of CS{alpha}{beta}-type defensins. -- Abstract: Ancient invertebrate-type and classical insect-type defensins (AITDs and CITDs) are two groups of evolutionarily related antimicrobial peptides (AMPs) that adopt a conserved cysteine-stabilized {alpha}-helical and {beta}-sheet (CS{alpha}{beta}) fold with a different amino-terminal loop (n-loop) size and diverse modes of antibacterial action. Although they both are identified as inhibitors of cell wall biosynthesis, only CITDs evolved membrane disruptive ability by peptide oligomerization to form pores. To understand how this occurred, we modified micasin, a fungus-derived AITDs with a non-membrane disruptive mechanism, by substituting its n-loop with that of an insect-derived CITDs. After air oxidization, the synthetic hybrid defensin (termed Al-M) was structurally identified by circular dichroism (CD) and functionally evaluated by antibacterial and membrane permeability assays and electronic microscopic observation. Results showed that Al-M folded into a native-like defensin structure, as determined by its CD spectrum that is similar to that of micasin. Al-M was highly efficacious against the Gram-positive bacterium Bacillus megaterium with a lethal concentration of 1.76 {mu}M. As expected, in contrast to micasin, Al-M killed the bacteria through a membrane disruptive mechanism of action. The alteration in modes of action supports a key role of the n-loop extension in assembling functional surface of CITDs for membrane disruption. Our work provides mechanical evidence for evolutionary relationship between AITDs and CITDs.

Alteration of the mode of antibacterial action of a defensin by the amino-terminal loop substitution

International Nuclear Information System (INIS)

Gao, Bin; Zhu, Shunyi

2012-01-01

Highlights: ► Al-M is an engineered fungal defensin with the n-loop of an insect defensin. ► Al-M adopts a native defensin-like structure with high antibacterial potency. ► Al-M kills bacteria through a membrane disruptive mechanism. ► This work sheds light on the functional evolution of CSαβ-type defensins. -- Abstract: Ancient invertebrate-type and classical insect-type defensins (AITDs and CITDs) are two groups of evolutionarily related antimicrobial peptides (AMPs) that adopt a conserved cysteine-stabilized α-helical and β-sheet (CSαβ) fold with a different amino-terminal loop (n-loop) size and diverse modes of antibacterial action. Although they both are identified as inhibitors of cell wall biosynthesis, only CITDs evolved membrane disruptive ability by peptide oligomerization to form pores. To understand how this occurred, we modified micasin, a fungus-derived AITDs with a non-membrane disruptive mechanism, by substituting its n-loop with that of an insect-derived CITDs. After air oxidization, the synthetic hybrid defensin (termed Al-M) was structurally identified by circular dichroism (CD) and functionally evaluated by antibacterial and membrane permeability assays and electronic microscopic observation. Results showed that Al-M folded into a native-like defensin structure, as determined by its CD spectrum that is similar to that of micasin. Al-M was highly efficacious against the Gram-positive bacterium Bacillus megaterium with a lethal concentration of 1.76 μM. As expected, in contrast to micasin, Al-M killed the bacteria through a membrane disruptive mechanism of action. The alteration in modes of action supports a key role of the n-loop extension in assembling functional surface of CITDs for membrane disruption. Our work provides mechanical evidence for evolutionary relationship between AITDs and CITDs.

Structural and functional characterization of the conserved salt bridge in mammalian paneth cell alpha-defensins

DEFF Research Database (Denmark)

Rosengren, K Johan; Daly, Norelle L; Fornander, Liselotte M

2006-01-01

alpha-Defensins are mediators of mammalian innate immunity, and knowledge of their structure-function relationships is essential for understanding their mechanisms of action. We report here the NMR solution structures of the mouse Paneth cell alpha-defensin cryptdin-4 (Crp4) and a mutant (E15D)-C...

Antiviral acyclic nucleoside phosphonates: New structures and prodrugs

Czech Academy of Sciences Publication Activity Database

Krečmerová, Marcela; Tichý, Tomáš; Pomeisl, Karel; Andrei, G.; Balzarini, J.; Snoeck, R.

2016-01-01

Roč. 1, č. 2 (2016), s. 37 [PharmaMed-2016. International Conference on Medicinal and Pharmaceutical Chemistry . 05.12.2016-07.12.2016, Dubai] R&D Projects: GA ČR(CZ) GA14-00522S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * prodrugs * antivirals * 5-azacytosine Subject RIV: CC - Organic Chemistry

Increased expression and levels of human β defensins (hBD2 and hBD4 in adults with dental caries

Directory of Open Access Journals (Sweden)

Girolamo Jose Barrera

2013-09-01

Full Text Available Introduction: Defensins are small anti-microbial peptides produced by epithelial cells. These peptides have a broad range of actions against microorganisms, including Gram-positive and Gram-negative bacteria.Human defensins are classifi ed into two subfamilies, the α-, and β- defensins, which differ in their distribution of disulphide bonds between the six conserved cysteine residues. Defensins are found in salivaand others compartments of the body. Human β defensins 2 (hBD2, beta defensins 4 (hBD4 and alpha defensins 4 (hNP4 in saliva may contributes to vulnerability or resistance to caries. This study aimed to determine a possible correlation between caries and levels of defensins measuring the expression in gingival tissue and concentrations in saliva samples.Methods: Oral examinations were performed on 100 adults of both genders (18-30 years old, and unstimulated whole saliva was collected for immunoassays of the three peptides and for the salivary pH, buffercapacity, protein, and peroxidase activity. mRNA levels of defensins in gingival sample were assessed by semi-quantitative RT-PCR technique.Results: The median salivary levels of hBD2 and hBD4 were 1.88 μg/ml and 0.86 μg/ml respectively for the caries-free group (n=44 and 7.26 μ/ml (hBD2 and 4.25 μg/ml (hBD4 for all subjects with evidenceof caries (n=56. There was no difference in the levels of hNP4, salivary pH, and proteins between groups, however the peroxidase activity and buffer capacity (interval 6.0-5.0 were reduced in caries group. Transcriptional levels of hBD2 and hBD4 did correlate with caries experience, the mRNA expression of hBD2 and hBD4 were signifi cantly higher in patients with caries than in patients with no-caries (p Conclusion: We conclude that high salivary levels and expression of beta defensins, low peroxidase activity and buffer capacity may represent a biological response of oral tissue to caries. Our observation couldlead to new ways to prevent caries

Increased expression and levels of human β defensins (hBD2 and hBD4 in adults with dental caries

Directory of Open Access Journals (Sweden)

Girolamo Jose Barrera

2013-09-01

Full Text Available Introduction: Defensins are small anti-microbial peptides produced by epithelial cells. These peptides have a broad range of actions against microorganisms, including Gram-positive and Gram-negative bacteria.Human defensins are classifi ed into two subfamilies, the α-, and β- defensins, which differ in their distribution of disulphide bonds between the six conserved cysteine residues. Defensins are found in salivaand others compartments of the body. Human β defensins 2 (hBD2, beta defensins 4 (hBD4 and alpha defensins 4 (hNP4 in saliva may contributes to vulnerability or resistance to caries. This study aimed to determine a possible correlation between caries and levels of defensins measuring the expression in gingival tissue and concentrations in saliva samples.Methods: Oral examinations were performed on 100 adults of both genders (18-30 years old, and unstimulated whole saliva was collected for immunoassays of the three peptides and for the salivary pH, buffercapacity, protein, and peroxidase activity. mRNA levels of defensins in gingival sample were assessed by semi-quantitative RT-PCR technique.Results: The median salivary levels of hBD2 and hBD4 were 1.88 μg/ml and 0.86 μg/ml respectively for the caries-free group (n=44 and 7.26 μ/ml (hBD2 and 4.25 μg/ml (hBD4 for all subjects with evidenceof caries (n=56. There was no difference in the levels of hNP4, salivary pH, and proteins between groups, however the peroxidase activity and buffer capacity (interval 6.0-5.0 were reduced in caries group. Transcriptional levels of hBD2 and hBD4 did correlate with caries experience, the mRNA expression of hBD2 and hBD4 were signifi cantly higher in patients with caries than in patients with no-caries (p < 0.01.Conclusion: We conclude that high salivary levels and expression of beta defensins, low peroxidase activity and buffer capacity may represent a biological response of oral tissue to caries. Our observation couldlead to new ways to prevent

Differential Susceptibility of Bacteria to Mouse Paneth Cell a-Defensins under Anaerobic Conditions

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Jennifer R. Mastroianni

2014-10-01

Full Text Available Small intestinal Paneth cells secrete a-defensin peptides, termed cryptdins (Crps in mice, into the intestinal lumen, where they confer immunity to oral infections and define the composition of the ileal microbiota. In these studies, facultative bacteria maintained under aerobic or anaerobic conditions displayed differential sensitivities to mouse a-defensins under in vitro assay conditions. Regardless of oxygenation, Crps 2 and 3 had robust and similar bactericidal activities against S. typhimurium and S. flexneri, but Crp4 activity against S. flexneri was attenuated in the absence of oxygen. Anaerobic bacteria varied in their susceptibility to Crps 2-4, with Crp4 showing less activity than Crps 2 and 3 against Enterococcus faecalis, and Bacteroides fragilis in anaerobic assays, but Fusobacterium necrophorum was killed only by Crp4 and not by Crps 2 and 3. The influence of anaerobiosis in modulating Crp bactericidal activities in vitro suggests that a-defensin effects on the enteric microbiota may be subject to regulation by local oxygen tension.

β-Defensin genomic copy number does not influence the age of onset in Huntington's Disease.

Science.gov (United States)

Vittori, Angelica; Orth, Michael; Roos, Raymund A C; Outeiro, Tiago F; Giorgini, Flaviano; Hollox, Edward J

2013-01-01

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by the abnormal expansion of a CAG triplet repeat tract in the huntingtin gene. While the length of this CAG expansion is the major determinant of the age of onset (AO), other genetic factors have also been shown to play a modulatory role. Recent evidence suggests that neuroinflammations is a pivotal factor in the pathogenesis of HD, and that targeting this process may have important therapeutic ramifications. The human β-defensin 2 (hBD2)- encoded by DEFB4- is an antimicrobial peptide that exhibits inducible expression in astrocytes during inflammation and is an important regulator of innate and adaptive immune response. Therefore, DEFB4 may contribute to the neuroinflammatory processes observed in HD. In this study we tested the hypothesis that copy number variation (CNV) of the β-defensin region, including DEFB4, modifies the AO in HD. We genotyped β-defensin CNV in 490 HD individuals using the paralogue ratio test and found no association between β-defensin CNV and onset of HD. We conclude that it is unlikely that DEFB4 plays a role in HD pathogenesis.

Intramolecular cascade rearrangements of enynamine derived ketenimines: access to acyclic and cyclic amidines.

Science.gov (United States)

Chauhan, Dinesh Pratapsinh; Varma, Sreejith J; Gudem, Mahesh; Panigrahi, Nihar; Singh, Khushboo; Hazra, Anirban; Talukdar, Pinaki

2017-06-07

Copper-catalyzed reaction of enynamines with sulfonylazides provides acyclic and cyclic amidines. Nucleophilic addition of the tethered amino group on the in situ generated ketenimine forms a six-membered cyclic zwitterionic intermediate which facilitates migration of the tethered amino group to the C 5 -center giving the acyclic amidine. On the other hand, migration of a substituent on the amino group to C 2 - and C 4 -centers results in the formation of cyclic amidines. Computational studies were carried out to validate the mechanism which indicates that the product distribution of the process depends on the substitutions on the enynamine backbone.

Big defensins, a diverse family of antimicrobial peptides that follows different patterns of expression in hemocytes of the oyster Crassostrea gigas.

Science.gov (United States)

Rosa, Rafael D; Santini, Adrien; Fievet, Julie; Bulet, Philippe; Destoumieux-Garzón, Delphine; Bachère, Evelyne

2011-01-01

Big defensin is an antimicrobial peptide composed of a highly hydrophobic N-terminal region and a cationic C-terminal region containing six cysteine residues involved in three internal disulfide bridges. While big defensin sequences have been reported in various mollusk species, few studies have been devoted to their sequence diversity, gene organization and their expression in response to microbial infections. Using the high-throughput Digital Gene Expression approach, we have identified in Crassostrea gigas oysters several sequences coding for big defensins induced in response to a Vibrio infection. We showed that the oyster big defensin family is composed of three members (named Cg-BigDef1, Cg-BigDef2 and Cg-BigDef3) that are encoded by distinct genomic sequences. All Cg-BigDefs contain a hydrophobic N-terminal domain and a cationic C-terminal domain that resembles vertebrate β-defensins. Both domains are encoded by separate exons. We found that big defensins form a group predominantly present in mollusks and closer to vertebrate defensins than to invertebrate and fungi CSαβ-containing defensins. Moreover, we showed that Cg-BigDefs are expressed in oyster hemocytes only and follow different patterns of gene expression. While Cg-BigDef3 is non-regulated, both Cg-BigDef1 and Cg-BigDef2 transcripts are strongly induced in response to bacterial challenge. Induction was dependent on pathogen associated molecular patterns but not damage-dependent. The inducibility of Cg-BigDef1 was confirmed by HPLC and mass spectrometry, since ions with a molecular mass compatible with mature Cg-BigDef1 (10.7 kDa) were present in immune-challenged oysters only. From our biochemical data, native Cg-BigDef1 would result from the elimination of a prepropeptide sequence and the cyclization of the resulting N-terminal glutamine residue into a pyroglutamic acid. We provide here the first report showing that big defensins form a family of antimicrobial peptides diverse not only in terms

Utilization of plant-derived recombinant human β-defensins (hBD-1 and hBD-2) for averting salmonellosis.

Science.gov (United States)

Patro, Sunita; Maiti, Soumitra; Panda, Santosh Kumar; Dey, Nrisingha

2015-04-01

We describe the use of plant-made β-defensins as effective antimicrobial substances for controlling salmonellosis, a deadly infection caused by Salmonella typhimurium (referred to further as S. typhi). Human β-defensin-1 (hBD-1) and -2 (hBD-2) were expressed under the control of strong constitutive promoters in tobacco plants, and bio-active β-defensins were successfully extracted. In the in vitro studies, enriched recombinant plant-derived human β-defensin-1 (phBD-1) and -2 (phBD-2) obtained from both T1 and T2 transgenic plants showed significant antimicrobial activity against Escherichia coli and S. typhi when used individually and in various combinations. The 2:1 peptide combination of phBD-1:phBD-2 with peptides isolated from T1-and T2-generation plants reduced the growth of S. typhi by 96 and 85 %, respectively. In vivo studies employing the mouse model (Balb/c) of Salmonella infection clearly demonstrated that the administration of plant-derived defensins individually and in different combinations enhanced the mean survival time of Salmonella-infected animals. When treatment consisted of the 2:1 phBD-1:phBD-2 combination, approximately 50 % of the infected mice were still alive at 206 h post-inoculation; the lowest number of viable S. typhi was observed in the liver and spleen of infected animals. We conclude that plant-made recombinant β-defensins (phBD-1 and phBD-2) are promising antimicrobial substances and have the potential to become additional tools against salmonellosis, particularly when used in combination.

Mode of action of plant defensins suggests therapeutic potential

NARCIS (Netherlands)

Thomma, B.P.H.J.; Cammue, B.P.A.; Thevissen, K.

2003-01-01

Higher vertebrates can rely both on an innate as well as an adaptive immune system for defense against invading pathogens. In contrast, plants can only employ an innate immune system that largely depends on the production of antimicrobial compounds such as plant defensins and other

Polynomial kernels for deletion to classes of acyclic digraphs

NARCIS (Netherlands)

Mnich, Matthias; van Leeuwen, E.J.

2017-01-01

We consider the problem to find a set X of vertices (or arcs) with |X| ≤ k in a given digraph G such that D = G − X is an acyclic digraph. In its generality, this is Directed Feedback Vertex Set (or Directed Feedback Arc Set); the existence of a polynomial kernel for these problems is a notorious

A Defensin from the Model Beetle Tribolium castaneum Acts Synergistically with Telavancin and Daptomycin against Multidrug Resistant Staphylococcus aureus.

Science.gov (United States)

Rajamuthiah, Rajmohan; Jayamani, Elamparithi; Conery, Annie L; Fuchs, Beth Burgwyn; Kim, Wooseong; Johnston, Tatiana; Vilcinskas, Andreas; Ausubel, Frederick M; Mylonakis, Eleftherios

2015-01-01

The red flour beetle Tribolium castaneum is a common insect pest and has been established as a model beetle to study insect development and immunity. This study demonstrates that defensin 1 from T. castaneum displays in vitro and in vivo antimicrobial activity against drug resistant Staphylococcus aureus strains. The minimum inhibitory concentration (MIC) of defensin 1 against 11 reference and clinical staphylococcal isolates was between 16-64 μg/ml. The putative mode of action of the defensin peptide is disruption of the bacterial cell membrane. The antibacterial activity of defensin 1 was attenuated by salt concentrations of 1.56 mM and 25 mM for NaCl and CaCl2 respectively. Treatment of defensin 1 with the reducing agent dithiothreitol (DTT) at concentrations 1.56 to 3.13 mM abolished the antimicrobial activity of the peptide. In the presence of subinhibitory concentrations of antibiotics that also target the bacterial cell envelope such as telavancin and daptomycin, the MIC of the peptide was as low as 1 μg/ml. Moreover, when tested against an S. aureus strain that was defective in D-alanylation of the cell wall, the MIC of the peptide was 0.5 μg/ml. Defensin 1 exhibited no toxicity against human erythrocytes even at 400 μg/ml. The in vivo activity of the peptide was validated in a Caenorhabditis elegans-MRSA liquid infection assay. These results suggest that defensin 1 behaves similarly to other cationic AMPs in its mode of action against S. aureus and that the activity of the peptide can be enhanced in combination with other antibiotics with similar modes of action or with compounds that have the ability to decrease D-alanylation of the bacterial cell wall.

A Defensin from the Model Beetle Tribolium castaneum Acts Synergistically with Telavancin and Daptomycin against Multidrug Resistant Staphylococcus aureus.

Directory of Open Access Journals (Sweden)

Rajmohan Rajamuthiah

Full Text Available The red flour beetle Tribolium castaneum is a common insect pest and has been established as a model beetle to study insect development and immunity. This study demonstrates that defensin 1 from T. castaneum displays in vitro and in vivo antimicrobial activity against drug resistant Staphylococcus aureus strains. The minimum inhibitory concentration (MIC of defensin 1 against 11 reference and clinical staphylococcal isolates was between 16-64 μg/ml. The putative mode of action of the defensin peptide is disruption of the bacterial cell membrane. The antibacterial activity of defensin 1 was attenuated by salt concentrations of 1.56 mM and 25 mM for NaCl and CaCl2 respectively. Treatment of defensin 1 with the reducing agent dithiothreitol (DTT at concentrations 1.56 to 3.13 mM abolished the antimicrobial activity of the peptide. In the presence of subinhibitory concentrations of antibiotics that also target the bacterial cell envelope such as telavancin and daptomycin, the MIC of the peptide was as low as 1 μg/ml. Moreover, when tested against an S. aureus strain that was defective in D-alanylation of the cell wall, the MIC of the peptide was 0.5 μg/ml. Defensin 1 exhibited no toxicity against human erythrocytes even at 400 μg/ml. The in vivo activity of the peptide was validated in a Caenorhabditis elegans-MRSA liquid infection assay. These results suggest that defensin 1 behaves similarly to other cationic AMPs in its mode of action against S. aureus and that the activity of the peptide can be enhanced in combination with other antibiotics with similar modes of action or with compounds that have the ability to decrease D-alanylation of the bacterial cell wall.

Towards Optimal Event Detection and Localization in Acyclic Flow Networks

KAUST Repository

Agumbe Suresh, Mahima

2012-01-03

Acyclic flow networks, present in many infrastructures of national importance (e.g., oil & gas and water distribution systems), have been attracting immense research interest. Existing solutions for detecting and locating attacks against these infrastructures, have been proven costly and imprecise, especially when dealing with large scale distribution systems. In this paper, to the best of our knowledge for the first time, we investigate how mobile sensor networks can be used for optimal event detection and localization in acyclic flow networks. Sensor nodes move along the edges of the network and detect events (i.e., attacks) and proximity to beacon nodes with known placement in the network. We formulate the problem of minimizing the cost of monitoring infrastructure (i.e., minimizing the number of sensor and beacon nodes deployed), while ensuring a degree of sensing coverage in a zone of interest and a required accuracy in locating events. We propose algorithms for solving these problems and demonstrate their effectiveness with results obtained from a high fidelity simulator.

Synergistic effect of interleukin 1 alpha on nontypeable Haemophilus influenzae-induced up-regulation of human beta-defensin 2 in middle ear epithelial cells

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Park Raekil

2006-01-01

Full Text Available Abstract Background We recently showed that beta-defensins have antimicrobial activity against nontypeable Haemophilus influenzae (NTHi and that interleukin 1 alpha (IL-1 alpha up-regulates the transcription of beta-defensin 2 (DEFB4 according to new nomenclature of the Human Genome Organization in human middle ear epithelial cells via a Src-dependent Raf-MEK1/2-ERK signaling pathway. Based on these observations, we investigated if human middle ear epithelial cells could release IL-1 alpha upon exposure to a lysate of NTHi and if this cytokine could have a synergistic effect on beta-defensin 2 up-regulation by the bacterial components. Methods The studies described herein were carried out using epithelial cell lines as well as a murine model of acute otitis media (OM. Human cytokine macroarray analysis was performed to detect the released cytokines in response to NTHi exposure. Real time quantitative PCR was done to compare the induction of IL-1 alpha or beta-defensin 2 mRNAs and to identify the signaling pathways involved. Direct activation of the beta-defensin 2 promoter was monitored using a beta-defensin 2 promoter-Luciferase construct. An IL-1 alpha blocking antibody was used to demonstrate the direct involvement of this cytokine on DEFB4 induction. Results Middle ear epithelial cells released IL-1 alpha when stimulated by NTHi components and this cytokine acted in an autocrine/paracrine synergistic manner with NTHi to up-regulate beta-defensin 2. This synergistic effect of IL-1 alpha on NTHi-induced beta-defensin 2 up-regulation appeared to be mediated by the p38 MAP kinase pathway. Conclusion We demonstrate that IL-1 alpha is secreted by middle ear epithelial cells upon exposure to NTHi components and that it can synergistically act with certain of these molecules to up-regulate beta-defensin 2 via the p38 MAP kinase pathway.

Big Defensins, a Diverse Family of Antimicrobial Peptides That Follows Different Patterns of Expression in Hemocytes of the Oyster Crassostrea gigas

Science.gov (United States)

Rosa, Rafael D.; Santini, Adrien; Fievet, Julie; Bulet, Philippe; Destoumieux-Garzón, Delphine; Bachère, Evelyne

2011-01-01

Background Big defensin is an antimicrobial peptide composed of a highly hydrophobic N-terminal region and a cationic C-terminal region containing six cysteine residues involved in three internal disulfide bridges. While big defensin sequences have been reported in various mollusk species, few studies have been devoted to their sequence diversity, gene organization and their expression in response to microbial infections. Findings Using the high-throughput Digital Gene Expression approach, we have identified in Crassostrea gigas oysters several sequences coding for big defensins induced in response to a Vibrio infection. We showed that the oyster big defensin family is composed of three members (named Cg-BigDef1, Cg-BigDef2 and Cg-BigDef3) that are encoded by distinct genomic sequences. All Cg-BigDefs contain a hydrophobic N-terminal domain and a cationic C-terminal domain that resembles vertebrate β-defensins. Both domains are encoded by separate exons. We found that big defensins form a group predominantly present in mollusks and closer to vertebrate defensins than to invertebrate and fungi CSαβ-containing defensins. Moreover, we showed that Cg-BigDefs are expressed in oyster hemocytes only and follow different patterns of gene expression. While Cg-BigDef3 is non-regulated, both Cg-BigDef1 and Cg-BigDef2 transcripts are strongly induced in response to bacterial challenge. Induction was dependent on pathogen associated molecular patterns but not damage-dependent. The inducibility of Cg-BigDef1 was confirmed by HPLC and mass spectrometry, since ions with a molecular mass compatible with mature Cg-BigDef1 (10.7 kDa) were present in immune-challenged oysters only. From our biochemical data, native Cg-BigDef1 would result from the elimination of a prepropeptide sequence and the cyclization of the resulting N-terminal glutamine residue into a pyroglutamic acid. Conclusions We provide here the first report showing that big defensins form a family of antimicrobial

Big defensins, a diverse family of antimicrobial peptides that follows different patterns of expression in hemocytes of the oyster Crassostrea gigas.

Directory of Open Access Journals (Sweden)

Rafael D Rosa

Full Text Available BACKGROUND: Big defensin is an antimicrobial peptide composed of a highly hydrophobic N-terminal region and a cationic C-terminal region containing six cysteine residues involved in three internal disulfide bridges. While big defensin sequences have been reported in various mollusk species, few studies have been devoted to their sequence diversity, gene organization and their expression in response to microbial infections. FINDINGS: Using the high-throughput Digital Gene Expression approach, we have identified in Crassostrea gigas oysters several sequences coding for big defensins induced in response to a Vibrio infection. We showed that the oyster big defensin family is composed of three members (named Cg-BigDef1, Cg-BigDef2 and Cg-BigDef3 that are encoded by distinct genomic sequences. All Cg-BigDefs contain a hydrophobic N-terminal domain and a cationic C-terminal domain that resembles vertebrate β-defensins. Both domains are encoded by separate exons. We found that big defensins form a group predominantly present in mollusks and closer to vertebrate defensins than to invertebrate and fungi CSαβ-containing defensins. Moreover, we showed that Cg-BigDefs are expressed in oyster hemocytes only and follow different patterns of gene expression. While Cg-BigDef3 is non-regulated, both Cg-BigDef1 and Cg-BigDef2 transcripts are strongly induced in response to bacterial challenge. Induction was dependent on pathogen associated molecular patterns but not damage-dependent. The inducibility of Cg-BigDef1 was confirmed by HPLC and mass spectrometry, since ions with a molecular mass compatible with mature Cg-BigDef1 (10.7 kDa were present in immune-challenged oysters only. From our biochemical data, native Cg-BigDef1 would result from the elimination of a prepropeptide sequence and the cyclization of the resulting N-terminal glutamine residue into a pyroglutamic acid. CONCLUSIONS: We provide here the first report showing that big defensins form a family

Impossibility of an acyclic relativistic electric motor

Energy Technology Data Exchange (ETDEWEB)

Spavieri, G [Universidad de Los Andes, Merida (Venezuela); Cavalleri, G [Milan Univ. (Italy). Ist. di Fisica; Spinelli, G [Padua Univ. (Italy). Ist. di Matematica Applicata

1981-02-11

The relativistic torque acting on a circuit carrying a current and having a uniform translatory motion in a constant and uniform electric field would seem to suggest the possibility of an acyclic relativistic electric motor. However, the net effect on the side parallel to the rotation axis is exactly balanced by the variation of the angular momentum (in the case of an insulating circuit transporting electric charges) or by the external moment due to the magnetic field (in the case of a conducting circuit) acting on the two sides perpendicular to the rotation axis.

Ixodes ricinus defensins attack distantly-related pathogens

Czech Academy of Sciences Publication Activity Database

Tonk, M.; Cabezas-Cruz, A.; Valdés, James J.; Rego, Ryan O. M.; Grubhoffer, Libor; Estrada--Pena, A.; Vilcinskas, A.; Kotsyfakis, Michalis; Rahnamaeian, M.

2015-01-01

Roč. 53, č. 2 (2015), s. 358-365 ISSN 0145-305X R&D Projects: GA MŠk(CZ) EE2.3.30.0032; GA ČR GAP502/12/2409 EU Projects: European Commission(XE) 278976 Institutional support: RVO:60077344 Keywords : Antimicrobial peptide * Defensin * Ixodes ricinus * Listeria monocytogenes * Staphylococcus aureus * Staphylococcus epidermidis * Escherichia coli * Pseudomonas aeruginosa * Fusarium spp Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.620, year: 2015

On Event Detection and Localization in Acyclic Flow Networks

KAUST Repository

Suresh, Mahima Agumbe

2013-05-01

Acyclic flow networks, present in many infrastructures of national importance (e.g., oil and gas and water distribution systems), have been attracting immense research interest. Existing solutions for detecting and locating attacks against these infrastructures have been proven costly and imprecise, particularly when dealing with large-scale distribution systems. In this article, to the best of our knowledge, for the first time, we investigate how mobile sensor networks can be used for optimal event detection and localization in acyclic flow networks. We propose the idea of using sensors that move along the edges of the network and detect events (i.e., attacks). To localize the events, sensors detect proximity to beacons, which are devices with known placement in the network. We formulate the problem of minimizing the cost of monitoring infrastructure (i.e., minimizing the number of sensors and beacons deployed) in a predetermined zone of interest, while ensuring a degree of coverage by sensors and a required accuracy in locating events using beacons. We propose algorithms for solving the aforementioned problem and demonstrate their effectiveness with results obtained from a realistic flow network simulator.

Beta-Defensin 2 and 3 Promote Bacterial Clearance of Pseudomonas aeruginosa by Inhibiting Macrophage Autophagy through Downregulation of Early Growth Response Gene-1 and c-FOS

Directory of Open Access Journals (Sweden)

Yongjian Wu

2018-02-01

Full Text Available Beta-defensins 2 and 3 (BD2 and BD3 are inducible peptides present at the sites of infection, and they are well characterized for their antimicrobial activities and immune-regulatory functions. However, no study has thoroughly investigated their immunomodulatory effects on macrophage-mediated immune responses against Pseudomonas aeruginosa (PA. Here, we use THP-1 and RAW264.7 cell lines and demonstrate that BD2 and BD3 suppressed macrophage autophagy but enhanced the engulfment of PA and Zymosan bioparticles as well as the formation of phagolysosomes, using immunofluorescence staining and confocal microscopy. Plate count assay showed that macrophage-mediated phagocytosis and intracellular killing of PA were promoted by BD2 and BD3. Furthermore, microarray and real-time PCR showed that the expression of two genes, early growth response gene-1 (EGR1 and c-FOS, was attenuated by BD2 and BD3. Western blot revealed that BD2 and BD3 inhibited the expression and nuclear translocation of EGR1 and c-FOS. Knockdown of EGR1 and c-FOS by siRNA transfection suppressed macrophage autophagy before and after PA infection; while overexpression of these two transcription factors enhanced autophagy but reversed the role of BD2 and BD3 on macrophage-mediated PA eradication. Together, these results demonstrate a novel immune defense activity of BD2 and BD3, which promotes clearance of PA by inhibiting macrophage autophagy through downregulation of EGR1 and c-FOS.

Plant Defensins NaD1 and NaD2 Induce Different Stress Response Pathways in Fungi

Directory of Open Access Journals (Sweden)

Peter M. Dracatos

2016-09-01

Full Text Available Nicotiana alata defensins 1 and 2 (NaD1 and NaD2 are plant defensins from the ornamental tobacco that have antifungal activity against a variety of fungal pathogens. Some plant defensins interact with fungal cell wall O-glycosylated proteins. Therefore, we investigated if this was the case for NaD1 and NaD2, by assessing the sensitivity of the three Aspergillus nidulans (An O-mannosyltransferase (pmt knockout (KO mutants (An∆pmtA, An∆pmtB, and An∆pmtC. An∆pmtA was resistant to both defensins, while An∆pmtC was resistant to NaD2 only, suggesting NaD1 and NaD2 are unlikely to have a general interaction with O-linked side chains. Further evidence of this difference in the antifungal mechanism was provided by the dissimilarity of the NaD1 and NaD2 sensitivities of the Fusarium oxysporum f. sp. lycopersici (Fol signalling knockout mutants from the cell wall integrity (CWI and high osmolarity glycerol (HOG mitogen-activated protein kinase (MAPK pathways. HOG pathway mutants were sensitive to both NaD1 and NaD2, while CWI pathway mutants only displayed sensitivity to NaD2.

Metabolism of acyclic and cyclic N-nitroamines by cultured human colon

DEFF Research Database (Denmark)

Autrup, Herman; Harris, Curtis C.; Trump, Benjamin F.

1978-01-01

Cultured human colon mucosa was found to metabolize both acyclic and cyclic N-nitrosamines as measured by 14C-CO2 formation and reaction of the activated moieties with cellular macromolecules. Dimethylnitrosamine and N-nitrosopyrrolidine were metabolized by explants from all patients studied. A p...

Babesial vector tick defensin against Babesia sp. parasites.

Science.gov (United States)

Tsuji, Naotoshi; Battsetseg, Badgar; Boldbaatar, Damdinsuren; Miyoshi, Takeharu; Xuan, Xuenan; Oliver, James H; Fujisaki, Kozo

2007-07-01

Antimicrobial peptides are major components of host innate immunity, a well-conserved, evolutionarily ancient defensive mechanism. Infectious disease-bearing vector ticks are thought to possess specific defense molecules against the transmitted pathogens that have been acquired during their evolution. We found in the tick Haemaphysalis longicornis a novel parasiticidal peptide named longicin that may have evolved from a common ancestral peptide resembling spider and scorpion toxins. H. longicornis is the primary vector for Babesia sp. parasites in Japan. Longicin also displayed bactericidal and fungicidal properties that resemble those of defensin homologues from invertebrates and vertebrates. Longicin showed a remarkable ability to inhibit the proliferation of merozoites, an erythrocyte blood stage of equine Babesia equi, by killing the parasites. Longicin was localized at the surface of the Babesia sp. parasites, as demonstrated by confocal microscopic analysis. In an in vivo experiment, longicin induced significant reduction of parasitemia in animals infected with the zoonotic and murine B. microti. Moreover, RNA interference data demonstrated that endogenous longicin is able to directly kill the canine B. gibsoni, thus indicating that it may play a role in regulating the vectorial capacity in the vector tick H. longicornis. Theoretically, longicin may serve as a model for the development of chemotherapeutic compounds against tick-borne disease organisms.

Determination of beta-defensin genomic copy number in different populations

DEFF Research Database (Denmark)

Fode, Peder; Jespersgaard, Cathrine; Hardwick, Robert J

2011-01-01

There have been conflicting reports in the literature on association of gene copy number with disease, including CCL3L1 and HIV susceptibility, and ß-defensins and Crohn's disease. Quantification of precise gene copy numbers is important in order to define any association of gene copy number with...

Tribolium castaneum defensins are primarily active against Gram-positive bacteria

Czech Academy of Sciences Publication Activity Database

Tonk, M.; Knorr, E.; Cabezas-Cruz, A.; Valdés, James J.; Kollewe, C.; Vilcinskas, A.

2015-01-01

Roč. 132, NOV 2015 (2015), s. 208-215 ISSN 0022-2011 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Antimicrobial peptides * Defensin * Innate immunity * Insects * Tribolium castaneum * Gram-positive bacteria Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.198, year: 2015

A new recursive incremental algorithm for building minimal acyclic deterministic finite automata

NARCIS (Netherlands)

Watson, B.W.; Martin-Vide, C.; Mitrana, V.

2003-01-01

This chapter presents a new algorithm for incrementally building minimal acyclic deterministic finite automata. Such minimal automata are a compact representation of a finite set of words (e.g. in a spell checker). The incremental aspect of such algorithms (where the intermediate automaton is

The host defense peptide beta-defensin 1 confers protection against Bordetella pertussis in newborn piglets.

Science.gov (United States)

Elahi, Shokrollah; Buchanan, Rachelle M; Attah-Poku, Sam; Townsend, Hugh G G; Babiuk, Lorne A; Gerdts, Volker

2006-04-01

Innate immunity plays an important role in protection against respiratory infections in humans and animals. Host defense peptides such as beta-defensins represent major components of innate immunity. We recently developed a novel porcine model of pertussis, an important respiratory disease of young children and infants worldwide. Here, we investigated the role of porcine beta-defensin 1 (pBD-1), a porcine defensin homologue of human beta-defensin 2, in conferring protection against respiratory infection with Bordetella pertussis. In this model, newborn piglets were fully susceptible to infection and developed severe bronchopneumonia. In contrast, piglets older than 4 weeks of age were protected against infection with B. pertussis. Protection was associated with the expression of pBD-1 in the upper respiratory tract. In fact, pBD-1 expression was developmentally regulated, and the absence of pBD-1 was thought to contribute to the increased susceptibility of newborn piglets to infection with B. pertussis. Bronchoalveolar lavage specimens collected from older animals as well as chemically synthesized pBD-1 displayed strong antimicrobial activity against B. pertussis in vitro. Furthermore, in vivo treatment of newborn piglets with only 500 mug pBD-1 at the time of challenge conferred protection against infection with B. pertussis. Interestingly, pBD-1 displayed no bactericidal activity in vitro against Bordetella bronchiseptica, a closely related natural pathogen of pigs. Our results demonstrate that host defense peptides play an important role in protection against pertussis and are essential in modulating innate immune responses against respiratory infections.

Expression of a radish defensin in transgenic wheat confers increased resistance to Fusarium graminearum and Rhizoctonia cerealis.

Science.gov (United States)

Li, Zhao; Zhou, Miaoping; Zhang, Zengyan; Ren, Lijuan; Du, Lipu; Zhang, Boqiao; Xu, Huijun; Xin, Zhiyong

2011-03-01

Fusarium head blight (scab), primarily caused by Fusarium graminearum, is a devastating disease of wheat (Triticum aestivum L.) worldwide. Wheat sharp eyespot, mainly caused by Rhizoctonia cerealis, is one of the major diseases of wheat in China. The defensin RsAFP2, a small cyteine-rich antifungal protein from radish (Raphanus sativus), was shown to inhibit growth in vitro of agronomically important fungal pathogens, such as F. graminearum and R. cerealis. The RsAFP2 gene was transformed into Chinese wheat variety Yangmai 12 via biolistic bombardment to assess the effectiveness of the defensin in protecting wheat from the fungal pathogens in multiple locations and years. The genomic PCR and Southern blot analyses indicated that RsAFP2 was integrated into the genomes of the transgenic wheat lines and heritable. RT-PCR and Western blot proved that the RsAFP2 was expressed in these transgenic wheat lines. Disease tests showed that four RsAFP2 transgenic lines (RA1-RA4) displayed enhanced resistance to F. graminearum compared to the untransformed Yangmai 12 and the null-segregated plants. Assays on Q-RT-PCR and disease severity showed that the express level of RsAFP2 was associated with the enhanced resistance degree. Two of these transgenic lines (RA1 and RA2) also exhibited enhanced resistance to R. cerealis. These results indicated that the expression of RsAFP2 conferred increased resistance to F. graminearum and R. cerealis in transgenic wheat.

Ultrasound-assisted catalytic synthesis of acyclic imides in the presence of p-toluenesulfonic acid under solvent free conditions

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Nasr-Esfahani Masoud

2012-01-01

Full Text Available A rapid and convenient preparation of acyclic imides by the reaction of aliphatic and aromatic nitriles with acyclic carboxylic anhydride in the presence of catalytic amounts of p-toluenesulfonic acid under thermal or ultrasonic conditions is reported. The advantages of this procedure are moderate reaction times, good to excellent yields, use of inexpensive and ecofriendly catalyst. The reaction of nitriles with aliphatic anhydrides proceeds in thermal conditions, while by the use of ultrasound irradiations these reactions get accelerated.

Plant defensins and their potential use as pest control in agriculture

International Nuclear Information System (INIS)

Rojas Arias, Adriana Carolina; Zamora Espitia, Humberto Miguel

2010-01-01

Plants, as all organisms in nature, have elaborate systems of defense against pathogens; which can be physical or chemical and produced in a constitutive and induced way. Among the induced chemical barriers, there is a group of low molecular weight proteins, known as antimicrobial peptides (AMPs). These peptides include defensins, which are peptides with a molecular weight about 5 to 7 KDa, isoelectric point of 9, and length of about 45 to 55 amino acids. Likewise, they have the ability to avoid the growth of phytopathogenic microorganisms, mainly funguses. Moreover, these peptides create resistance to abiotic conditions of stress in plants. This manuscript seeks to make a clear and current description about the recent characteristics and researches related to plant defensins and their most significant uses in pathogens management in crops of economical relevance. It also intends to go deep into the study of such proteins in order to use them as a control strategy, such as production of transgenic plants and microorganisms.

Correlation of levels of alpha-defensins determined by HPLC-ESI-MS in bronchoalveolar lavage fluid with the diagnosis of pneumonia in premature neonates.

Science.gov (United States)

Tirone, Chiara; Boccacci, Simona; Inzitari, Rosanna; Tana, Milena; Aurilia, Claudia; Fanali, Chiara; Cabras, Tiziana; Messana, Irene; Castagnola, Massimo; Romagnoli, Costantino; Vento, Giovanni

2010-08-01

The presence of alpha-defensins in bronchoalveolar lavage fluid (BALF) was investigated in a cohort of preterm newborns with gestational age (GA) groups: pneumonia group of nine neonates suffering from pulmonary infection (GA: 26.1 +/- 2.1 wk; birth weight: 787.4 +/- 309.9 g), with or without associated bloodstream infection, and nonpneumonia group of 15 neonates (GA: 27.7 +/- 2.0 wk; birth weight: 1019.0 +/- 319.8 g). BALF culture was positive for CONS (n = 5), Staphylococcus aureus (n = 1), and Candida spp (n = 3). BALF samples were analyzed by HPLC-electrospray Ionization-mass spectrometer. The alpha-defensins 1-4 concentration, absolute and differential white cells count were measured. Relative amounts of alpha-defensins 1-4 and the absolute number of neutrophils were found significantly higher in the pneumonia group with respect to the nonpneumonia group (p < 0.05). Moreover, positive significant correlations between the number of neutrophils and the alpha-defensins 1-3 levels were observed. In conclusion, our data show that preterm newborns, also at the lower GA, are able to produce alpha-defensins, underlining that their innate defense system is already active before the at-term delivery date.

Existence principles for inclusions of Hammerstein type involving noncompact acyclic multivalued maps

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Jean-Francois Couchouron

2002-01-01

Full Text Available We apply Monch type fixed point theorems for acyclic multivalued maps to the solvability of inclusions of Hammerstein type in Banach spaces. Our approach makes possible to unify and improve the existence theories for nonlinear evolution problems and abstract integral inclusions of Volterra and Fredholm type.

Secretion of antiretroviral chemokines by human cells cultured with acyclic nucleoside phosphonates

Czech Academy of Sciences Publication Activity Database

Zídek, Zdeněk; Kmoníčková, Eva; Holý, Antonín

2007-01-01

Roč. 574, - (2007), s. 77-84 ISSN 0014-2999 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z40550506 Keywords : Acyclic nucleoside phosphonate * Chemokine * Cytokine Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.376, year: 2007

The Unusual Resistance of Avian Defensin AvBD7 to Proteolytic Enzymes Preserves Its Antibacterial Activity.

Science.gov (United States)

Bailleul, Geoffrey; Kravtzoff, Amanda; Joulin-Giet, Alix; Lecaille, Fabien; Labas, Valérie; Meudal, Hervé; Loth, Karine; Teixeira-Gomes, Ana-Paula; Gilbert, Florence B; Coquet, Laurent; Jouenne, Thierry; Brömme, Dieter; Schouler, Catherine; Landon, Céline; Lalmanach, Gilles; Lalmanach, Anne-Christine

2016-01-01

Defensins are frontline peptides of mucosal immunity in the animal kingdom, including birds. Their resistance to proteolysis and their ensuing ability to maintain antimicrobial potential remains questionable and was therefore investigated. We have shown by bottom-up mass spectrometry analysis of protein extracts that both avian beta-defensins AvBD2 and AvBD7 were ubiquitously distributed along the chicken gut. Cathepsin B was found by immunoblotting in jejunum, ileum, caecum, and caecal tonsils, while cathepsins K, L, and S were merely identified in caecal tonsils. Hydrolysis product of AvBD2 and AvBD7 incubated with a panel of proteases was analysed by RP-HPLC, mass spectrometry and antimicrobial assays. AvBD2 and AvBD7 were resistant to serine proteases and to cathepsins D and H. Conversely cysteine cathepsins B, K, L, and S degraded AvBD2 and abolished its antibacterial activity. Only cathepsin K cleaved AvBD7 and released Ile4-AvBD7, a N-terminal truncated natural peptidoform of AvBD7 that displayed antibacterial activity. Besides the 3-stranded antiparallel beta-sheet typical of beta-defensins, structural analysis of AvBD7 by two-dimensional NMR spectroscopy highlighted the restricted accessibility of the C-terminus embedded by the N-terminal region and gave a formal evidence of a salt bridge (Asp9-Arg12) that could account for proteolysis resistance. The differential susceptibility of avian defensins to proteolysis opens intriguing questions about a distinctive role in the mucosal immunity against pathogen invasion.

Gene organization of a novel defensin of Ixodes ricinus: first annotation of an intron/exon structure in a hard tick defensin gene and first evidence of the occurrence of two isoforms of one member of the arthropod defensin family

Czech Academy of Sciences Publication Activity Database

Rudenko, Natalia; Golovchenko, Maryna; Grubhoffer, Libor

2007-01-01

Roč. 16, č. 4 (2007), s. 501-507 ISSN 0962-1075 R&D Projects: GA MŠk(CZ) LC06009; GA ČR(CZ) GA524/06/1479 Institutional research plan: CEZ:AV0Z60220518 Keywords : defensin * Ixodes ricinus * intron/exon structure * immune response * antimicrobial activity Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.787, year: 2007

Highly selective Ba2+ separations with acyclic, lipophilic di-[N-(X)sulfonyl carbamoyl] polyethers.

Science.gov (United States)

Elshani, Sadik; Chun, Sangki; Amiri-Eliasi, Bijan; Bartsch, Richard A

2005-01-14

New lipophilic acyclic polyethers with two N-(X)sulfonyl carbamoyl groups of "tunable" acidity exhibit remarkable selectivity for Ba2+ over other alkaline earth metal ions in competitive solvent extraction and transport across polymer inclusion membranes.

Plectasin, a Fungal Defensin, Targets the Bacterial Cell Wall Precursor Lipid II

DEFF Research Database (Denmark)

Schneider, Tanja; Kruse, Thomas; Wimmer, Reinhard

2010-01-01

Host defense peptides such as defensins are components of innate immunity and have retained antibiotic activity throughout evolution. Their activity is thought to be due to amphipathic structures, which enable binding and disruption of microbial cytoplasmic membranes. Contrary to this, we show th...

Comparison of construction algorithms for minimal, acyclic, deterministic, finite-state automata from sets of strings

NARCIS (Netherlands)

Daciuk, J; Champarnaud, JM; Maurel, D

2003-01-01

This paper compares various methods for constructing minimal, deterministic, acyclic, finite-state automata (recognizers) from sets of words. Incremental, semi-incremental, and non-incremental methods have been implemented and evaluated.

Novel phenotype of mouse spermatozoa following deletion of nine β-defensin genes.

Science.gov (United States)

Dorin, Julia R

2015-01-01

β-defensin peptides are a large family of antimicrobial peptides. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. Despite their inducible presence at mucosal surfaces, their main site of expression is the epididymis. Recent evidence suggests that a major function of these peptides is in sperm maturation. In addition to previous work suggesting this, work at the MRC Human Genetics Unit, Edinburgh, has shown that homozygous deletion of a cluster of nine β-defensin genes in the mouse results in profound male sterility. The spermatozoa derived from the mutants had reduced motility and increased fragility. Epididymal spermatozoa isolated from the cauda region of the homozygous mutants demonstrated precocious capacitation and increased spontaneous acrosome reactions compared with those from wild-types. Despite this, these mutant spermatozoa had reduced ability to bind to the zona pellucida of oocytes. Ultrastructural examination revealed a disintegration of the microtubule structure of mutant-derived spermatozoa isolated from the epididymal cauda region, but not from the caput. Consistent with premature acrosome reaction and hyperactivation, spermatozoa from mutant animals had significantly increased intracellular calcium content. This work demonstrates that in vivo β-defensins are essential for successful sperm maturation, and that their disruption alters intracellular calcium levels, which most likely leads to premature activation and spontaneous acrosome reactions that result in hyperactivation and loss of microtubule structure of the axoneme. Determining which of the nine genes are responsible for the phenotype and the relevance to human sperm function is important for future work on male infertility.

Transfer and expression of the rabbit defensin NP-1 gene in lettuce (Lactuca sativa).

Science.gov (United States)

Song, D; Xiong, X; Tu, W F; Yao, W; Liang, H W; Chen, F J; He, Z Q

2017-01-23

Lettuce (Lactuca sativa L.) is an annual plant of the daisy family, Asteraceae, with high food and medicinal value. However, the crop is susceptible to several viruses that are transmitted by aphids and is highly vulnerable to post-harvest diseases, as well as insect and mammal pests and fungal and bacterial diseases. Here, the rabbit defensin gene NP-1 was transferred into lettuce by Agrobacterium-mediated transformation to obtain a broad-spectrum disease-resistant lettuce. Transgenic lettuce plants were selected and regenerated on selective media. The presence of the NP-1 gene in these plants was confirmed by western blot analyses. Resistance tests revealed native defensin NP-1 expression conferred partial resistance to Bacillus subtilis and Pseudomonas aeruginosa, which suggests new possibilities for lettuce disease resistance.

Antiplasmodial Activity Is an Ancient and Conserved Feature of Tick Defensins

Czech Academy of Sciences Publication Activity Database

Cabezas Cruz, Alejandro; Tonk, M.; Bouchut, A.; Pierrot, C.; Pierce, R.J.; Kotsyfakis, Michalis; Rahnamaeian, M.; Vilcinskas, A.; Khalife, J.; Valdés, James J.

2016-01-01

Roč. 7, 24 October (2016), č. článku 1682. ISSN 1664-302X R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : ticks * defensins * antimicrobial spectrum * ancestral sequence reconstruction * Plasmodium falciparum Subject RIV: EI - Biotechnology ; Bionics Impact factor: 4.076, year: 2016

New prodrugs of two pyrimidine acyclic nucleoside phosphonates: Synthesis and antiviral activity

Czech Academy of Sciences Publication Activity Database

Krečmerová, Marcela; Dračínský, Martin; Snoeck, R.; Balzarini, J.; Pomeisl, Karel; Andrei, G.

2017-01-01

Roč. 25, č. 17 (2017), s. 4637-4648 ISSN 0968-0896 R&D Projects: GA ČR(CZ) GA14-00522S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * open-ring * PMEO-DAPy * 5-azacytosine * PME-azaC * HPMP-5-azaC Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.930, year: 2016

Lactobacillus salivarius reverse diabetes-induced intestinal defense impairment in mice through non-defensin protein.

Science.gov (United States)

Chung, Pei-Hsuan; Wu, Ying-Ying; Chen, Pei-Hsuan; Fung, Chang-Phone; Hsu, Ching-Mei; Chen, Lee-Wei

2016-09-01

Altered intestinal microbiota and subsequent endotoxemia play pathogenic roles in diabetes. We aimed to study the mechanisms of intestinal defense impairment in type 1 diabetes and the effects of Lactobacillus salivarius as well as fructooligosaccharides (FOS) supplementation on diabetes-induced bacterial translocation. Alterations in the enteric microbiome, expression of mucosal antibacterial proteins and bacteria-killing activity of the intestinal mucosa in streptozotocin (STZ)-induced diabetic mice and Ins2(Akita) mice were investigated. The effects of dead L. salivarius (2×10(8)CFU/ml) and FOS (250 mg per day) supplementation for 1 week on endotoxin levels and Klebsiella pneumoniae translocation were also examined. Finally, germ-free mice were cohoused with wild-type or Ins2(Akita) mice for 2 weeks to examine the contribution of microbiota on the antibacterial protein expression. STZ-induced diabetic mice developed intestinal defense impairment as demonstrated by decreased mucosal bacteria-killing activity; reduction of non-defensin family proteins, such as Reg3β, Reg3γ, CRP-ductin and RELMβ, but not the defensin family proteins; and increased bacterial translocation. Intestinal bacteria overgrowth, enteric dysbiosis and increased intestinal bacterial translocation, particularly pathogenic K. pneumoniae in STZ-induced diabetic mice and Ins2(Akita) mice, were noted. Treating diabetic mice with dead L. salivarius or FOS reversed enteric dysbiosis, restored mucosal antibacterial protein and lessened endotoxin levels as well as K. pneumoniae translocation. Moreover, germ-free mice cohoused with wild-type mice demonstrated more intestinal Reg3β and RELMβ expression than those cohoused with Ins2(Akita) mice. These results indicate that hyperglycemia induces enteric dysbiosis, reduction of non-defensin proteins as well as bacteria-killing activity of the intestinal mucosa and intestinal defense impairment. Reversal of enteric dysbiosis with dead L. salivarius or

Gastrointestinal Autoimmunity Associated With Loss of Central Tolerance to Enteric alpha-Defensins

Czech Academy of Sciences Publication Activity Database

Dobeš, Jan; Neuwirth, Aleš; Dobešová, Martina; Vobořil, Matouš; Balounová, Jana; Ballek, Ondřej; Lebl, J.; Meloni, A.; Krohn, K.; Kluger, N.; Ranki, A.; Filipp, Dominik

2015-01-01

Roč. 149, č. 1 (2015), s. 139-150 ISSN 0016-5085 R&D Projects: GA ČR(CZ) GBP302/12/G101 Institutional support: RVO:68378050 Keywords : Enteric defensins * Intestinal autoimmunity * Mouse Model of APECED Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 18.187, year: 2015

Beta-defensin-2 protein is a serum biomarker for disease activity in psoriasis and reaches biologically relevant concentrations in lesional skin.

Directory of Open Access Journals (Sweden)

Patrick A M Jansen

Full Text Available BACKGROUND: Previous studies have extensively documented antimicrobial and chemotactic activities of beta-defensins. Human beta-defensin-2 (hBD-2 is strongly expressed in lesional psoriatic epidermis, and recently we have shown that high beta-defensin genomic copy number is associated with psoriasis susceptibility. It is not known, however, if biologically and pathophysiologically relevant concentrations of hBD-2 protein are present in vivo, which could support an antimicrobial and proinflammatory role of beta-defensins in lesional psoriatic epidermis. METHODOLOGY/PRINCIPAL FINDINGS: We found that systemic levels of hBD-2 showed a weak but significant correlation with beta defensin copy number in healthy controls but not in psoriasis patients with active disease. In psoriasis patients but not in atopic dermatitis patients, we found high systemic hBD-2 levels that strongly correlated with disease activity as assessed by the PASI score. Our findings suggest that systemic levels in psoriasis are largely determined by secretion from involved skin and not by genomic copy number. Modelling of the in vivo epidermal hBD-2 concentration based on the secretion rate in a reconstructed skin model for psoriatic epidermis provides evidence that epidermal hBD-2 levels in vivo are probably well above the concentrations required for in vitro antimicrobial and chemokine-like effects. CONCLUSIONS/SIGNIFICANCE: Serum hBD-2 appears to be a useful surrogate marker for disease activity in psoriasis. The discrepancy between hBD-2 levels in psoriasis and atopic dermatitis could explain the well known differences in infection rate between these two diseases.

Novel phenotype of mouse spermatozoa following deletion of nine β-defensin genes

Directory of Open Access Journals (Sweden)

Julia R Dorin

2015-01-01

Full Text Available β-defensin peptides are a large family of antimicrobial peptides. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. Despite their inducible presence at mucosal surfaces, their main site of expression is the epididymis. Recent evidence suggests that a major function of these peptides is in sperm maturation. In addition to previous work suggesting this, work at the MRC Human Genetics Unit, Edinburgh, has shown that homozygous deletion of a cluster of nine β-defensin genes in the mouse results in profound male sterility. The spermatozoa derived from the mutants had reduced motility and increased fragility. Epididymal spermatozoa isolated from the cauda region of the homozygous mutants demonstrated precocious capacitation and increased spontaneous acrosome reactions compared with those from wild-types. Despite this, these mutant spermatozoa had reduced ability to bind to the zona pellucida of oocytes. Ultrastructural examination revealed a disintegration of the microtubule structure of mutant-derived spermatozoa isolated from the epididymal cauda region, but not from the caput. Consistent with premature acrosome reaction and hyperactivation, spermatozoa from mutant animals had significantly increased intracellular calcium content. This work demonstrates that in vivo β-defensins are essential for successful sperm maturation, and that their disruption alters intracellular calcium levels, which most likely leads to premature activation and spontaneous acrosome reactions that result in hyperactivation and loss of microtubule structure of the axoneme. Determining which of the nine genes are responsible for the phenotype and the relevance to human sperm function is important for future work on male infertility.

Synthesis, structural studies and biological properties of new TBA analogues containing an acyclic nucleotide.

Science.gov (United States)

Coppola, Teresa; Varra, Michela; Oliviero, Giorgia; Galeone, Aldo; D'Isa, Giuliana; Mayol, Luciano; Morelli, Elena; Bucci, Maria-Rosaria; Vellecco, Valentina; Cirino, Giuseppe; Borbone, Nicola

2008-09-01

A new modified acyclic nucleoside, namely N(1)-(3-hydroxy-2-hydroxymethyl-2-methylpropyl)-thymidine, was synthesized and transformed into a building block useful for oligonucleotide (ON) automated synthesis. A series of modified thrombin binding aptamers (TBAs) in which the new acyclic nucleoside replaces, one at the time, the thymidine residues were then synthesized and characterized by UV, CD, MS, and (1)H NMR. The biological activity of the resulting TBAs was tested by Prothrombin Time assay (PT assay) and by purified fibrinogen clotting assay. From a structural point of view, nearly all the new TBA analogues show a similar behavior as the unmodified counterpart, being able to fold into a bimolecular or monomolecular quadruplex structure depending on the nature of monovalent cations (sodium or potassium) coordinated in the quadruplex core. From the comparison of structural and biological data, some important structure-activity relationships emerged, particularly when the modification involved the TT loops. In agreement with previous studies we found that the folding ability of TBA analogues is more affected by modifications involving positions 4 and 13, rather than positions 3 and 12. On the other hand, the highest anti-thrombin activities were detected for aptamers containing the modification at T13 or T12 positions, thus indicating that the effects produced by the introduction of the acyclic nucleoside on the biological activity are not tightly connected with structure stabilities. It is noteworthy that the modification at T7 produces an ON being more stable and active than the natural TBA.

N-Branched acyclic nucleoside phosphonates as monomers for the synthesis of modified oligonucleotides

Czech Academy of Sciences Publication Activity Database

Hocková, Dana; Rosenbergová, Šárka; Ménová, Petra; Páv, Ondřej; Pohl, Radek; Novák, Pavel; Rosenberg, Ivan

2015-01-01

Roč. 13, č. 15 (2015), s. 4449-4458 ISSN 1477-0520 R&D Projects: GA ČR GAP207/11/0108; GA ČR GA13-26526S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * oligonucleotides * solid phase synthesis Subject RIV: CC - Organic Chemistry Impact factor: 3.559, year: 2015

Spatio-Temporal Expression Patterns of Arabidopsis thaliana and Medicago truncatula Defensin-Like Genes

Science.gov (United States)

Nallu, Sumitha; Wang, Lin; Botanga, Christopher J.; Gomez, S. Karen; Costa, Liliana M.; Harrison, Maria J.; Samac, Deborah A.; Glazebrook, Jane; Katagiri, Fumiaki; Gutierrez-Marcos, Jose F.; VandenBosch, Kathryn A.

2013-01-01

Plant genomes contain several hundred defensin-like (DEFL) genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species. PMID:23527067

Spatio-temporal expression patterns of Arabidopsis thaliana and Medicago truncatula defensin-like genes.

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Mesfin Tesfaye

Full Text Available Plant genomes contain several hundred defensin-like (DEFL genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species.

Diurnal rhythms in gonadotropins and progesterone in lactating and photoperiod induced acyclic hamsters

International Nuclear Information System (INIS)

Bridges, R.S.; Goldman, B.D.

1975-01-01

Levels of LH, FSH, and progesterone in serum were measured in lactating hamsters and in hamsters in which acyclicity was induced with altered photoperiod. Lactating hamsters were found to have low titers of LH, FSH, and progesterone in serum at 0900 (lights on 0500--1900) on Days 4, 9, 14, and 19 of lactation and increased levels of these hormones at 1600. Levels of LH and FSH in serum at both 0900 and 1600 remained relatively constant throughout lactation. In contrast, levels of progesterone in serum obtained at both 0900 and 1600 sampling times increased as lactation progressed. Ovariectomy on Day 9 of lactation reduced serum levels of progesterone at both 0900 and 1600 and eliminated the afternoon surge in progesterone in animals bled 5 days after surgery. The levels and pattern of LH in serum remained unchanged after ovariectomy in lactating hamsters. However, serum FSH levels in the ovariectomized, lactating animals were elevated at both 0900 and 1600 when compared to levels present in intact, lactating hamsters bled at the same times. Females which were acyclic due to altered photoperiod displayed similar patterns of LH, FSH, and progesterone in serum. Levels of LH, FSH, and progesterone in serum were low at 1000 (lights on 0500--1500) and were increased 2 to 10 fold at 1500. Ovariectomy was followed by lower progesterone levels in serum at 1000 and 1500 and eliminated the afternoon rise of this hormone. Serum levels of LH were unaffected by ovariectomy. As in lactating hamsters, levels of FSH in serum were elevated 3--4 days following ovariectomy at both bleeding times, but the levels were higher at 1500. These results indicate that acyclicity induced by lactation or exposure to a short photoperiod is characterized by similar diurnal patterns of circulating hormones in the hamster

Antibacterial activity and phospholipid recognition of the recombinant defensin J1-1 from Capsicum genus.

Science.gov (United States)

Guillén-Chable, Francisco; Arenas-Sosa, Iván; Islas-Flores, Ignacio; Corzo, Gerardo; Martinez-Liu, Cynthia; Estrada, Georgina

2017-08-01

The gene of the four disulfide-bridged defensin J1-1 from Capsicum was cloned into the expression vector pQE30 containing a 6His-tag as fusion protein. This construct was transfected into Origami strain of Escherichia coli and expressed after induction with isopropyl thiogalactoside (IPTG). The level of expression was 4 mg/L of culture medium, and the His-tagged recombinant defensin (HisXarJ1-1) was expressed exclusively into inclusion bodies. After solubilization, HisXarJ1-1 was purified by affinity and hydrophobic interaction chromatography. The reverse-phase HPLC profile of the HisXarJ1-1 product obtained from the affinity chromatography step showed single main peptide fraction of molecular masses of 7050.6 Da and after treatment with DTT a single fraction of 7, 042.6 Da corresponding to the reduced peptide was observed. An in vitro folding step of the HisXarJ1-1 generated a distinct profile of oxidized forms of the peptide this oxidized peptide was capable of binding phosphatidic acid in vitro. Possible dimer and oligomer of HisXarJ1-1 were visible in gel electrophoresis and immunodetected with anti-His antibodies. Pure recombinant defensin HisXarJ1-1 exhibited antibacterial activity against Pseudomonas aeruginosa. Copyright © 2017 Elsevier Inc. All rights reserved.

PaDef defensin from avocado (Persea americana var. drymifolia) is cytotoxic to K562 chronic myeloid leukemia cells through extrinsic apoptosis.

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Flores-Alvarez, Luis José; Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Salgado-Garciglia, Rafael; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

2018-06-01

Plant defensins, a group of antimicrobial peptides, show selective cytotoxicity toward cancer cells. However, their mechanisms of action remain poorly understood. Here, we evaluated the cytotoxicity of PaDef defensin from avocado (Persea americana var. drymifolia) on K562 chronic myeloid leukemia cells and analyzed the pathway involved in the induction of cell death. The defensin PaDef was not cytotoxic against human PBMCs; however, it was cytotoxic for K562 cell line (IC 50  = 97.3 μg/ml) activating apoptosis at 12 h. PaDef did not affect the mitochondrial membrane potential (ΔΨm), neither the transmembranal potential or the release of intracellular calcium. Also, PaDef induced gene expression of caspase 8 (∼2 fold), TNF-α (∼4 fold) and TNFR1 (∼10 fold). In addition, the activation of caspase 8 was detected at 24 h, whereas caspase 9 activity was not modified, suggesting that the extrinsic apoptosis pathway could be activated. In conclusion, PaDef induces apoptosis on K562 cells, which is related to the activation of caspase 8 and involves the participation of TNF-α, which is a novel property for a plant defensin. Copyright © 2018 Elsevier Ltd. All rights reserved.

Partial deletion of chromosome 8 β-defensin cluster confers sperm dysfunction and infertility in male mice.

Directory of Open Access Journals (Sweden)

Yu S Zhou

2013-10-01

Full Text Available β-defensin peptides are a family of antimicrobial peptides present at mucosal surfaces, with the main site of expression under normal conditions in the male reproductive tract. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. We show here that homozygous deletion of a cluster of nine β-defensin genes (DefbΔ9 in the mouse results in male sterility. The sperm derived from the mutants have reduced motility and increased fragility. Epididymal sperm isolated from the cauda should require capacitation to induce the acrosome reaction but sperm from the mutants demonstrate precocious capacitation and increased spontaneous acrosome reaction compared to wild-types but have reduced ability to bind the zona pellucida of oocytes. Ultrastructural examination reveals a defect in microtubule structure of the axoneme with increased disintegration in mutant derived sperm present in the epididymis cauda region, but not in caput region or testes. Consistent with premature acrosome reaction, sperm from mutant animals have significantly increased intracellular calcium content. Thus we demonstrate in vivo that β-defensins are essential for successful sperm maturation, and their disruption leads to alteration in intracellular calcium, inappropriate spontaneous acrosome reaction and profound male infertility.

Acyclic ketones in the defensive secretion of a "daddy longlegs" (Leiobunum vittatum).

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Meinwald, J; Kluge, A F; Carrel, J E; Eisner, T

1971-07-01

The defensive secretion of the "daddy longlegs" Leiobunum vittatum was analyzed and found to contain the acyclic ketones 4-methylheptan-3-one and E-4,6-dimethyl-6-octen-3-one as its major organic components. Although 4-methylheptan-3-one has been found previously as an alarm substance in certain ant genera, the second component, whose structure is confirmed by synthesis, is new.

Anti-Legionella dumoffii Activity of Galleria mellonella Defensin and Apolipophorin III

Directory of Open Access Journals (Sweden)

Małgorzata Cytryńska

2012-12-01

Full Text Available The gram-negative bacterium Legionella dumoffii is, beside Legionella pneumophila, an etiological agent of Legionnaires’ disease, an atypical form of pneumonia. The aim of this study was to determine the antimicrobial activity of Galleria mellonella defense polypeptides against L. dumoffii. The extract of immune hemolymph, containing a mixture of defense peptides and proteins, exhibited a dose-dependent bactericidal effect on L. dumoffii. The bacterium appeared sensitive to a main component of the hemolymph extract, apolipophorin III, as well as to a defense peptide, Galleria defensin, used at the concentrations 0.4 mg/mL and 40 μg/mL, respectively. L. dumoffii cells cultured in the presence of choline were more susceptible to both defense factors analyzed. A transmission electron microscopy study of bacterial cells demonstrated that Galleria defensin and apolipophorin III induced irreversible cell wall damage and strong intracellular alterations, i.e., increased vacuolization, cytoplasm condensation and the appearance of electron-white spaces in electron micrographs. Our findings suggest that insects, such as G. mellonella, with their great diversity of antimicrobial factors, can serve as a rich source of compounds for the testing of Legionella susceptibility to defense-related peptides and proteins.

Lucifensins, the Insect Defensins of Biomedical Importance: The Story behind Maggot Therapy

Czech Academy of Sciences Publication Activity Database

Čeřovský, Václav; Bém, R.

2014-01-01

Roč. 7, č. 3 (2014), s. 251-264 ISSN 1424-8247 R&D Projects: GA ČR GA203/08/0536 Institutional support: RVO:61388963 Keywords : antimicrobial peptide * insect defensin * lucifensin * maggot therapy * Lucilia sericata * Lucilia cuprina * peptide isolation * peptide identification Subject RIV: CC - Organic Chemistry http://www.mdpi.com/1424-8247/7/3/251

Giardia co-infection promotes the secretion of antimicrobial peptides beta-defensin 2 and trefoil factor 3 and attenuates attaching and effacing bacteria-induced intestinal disease.

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Manko, Anna; Motta, Jean-Paul; Cotton, James A; Feener, Troy; Oyeyemi, Ayodele; Vallance, Bruce A; Wallace, John L; Buret, Andre G

2017-01-01

Our understanding of polymicrobial gastrointestinal infections and their effects on host biology remains incompletely understood. Giardia duodenalis is an ubiquitous intestinal protozoan parasite infecting animals and humans. Concomitant infections with Giardia and other gastrointestinal pathogens commonly occur. In countries with poor sanitation, Giardia infection has been associated with decreased incidence of diarrheal disease and fever, and reduced serum inflammatory markers release, via mechanisms that remain obscure. This study analyzed Giardia spp. co-infections with attaching and effacing (A/E) pathogens, and assessed whether and how the presence of Giardia modulates host responses to A/E enteropathogens, and alters intestinal disease outcome. In mice infected with the A/E pathogen Citrobacter rodentium, co-infection with Giardia muris significantly attenuated weight loss, macro- and microscopic signs of colitis, bacterial colonization and translocation, while concurrently enhancing the production and secretion of antimicrobial peptides (AMPs) mouse β-defensin 3 and trefoil factor 3 (TFF3). Co-infection of human intestinal epithelial cells (Caco-2) monolayers with G. duodenalis trophozoites and enteropathogenic Escherichia coli (EPEC) enhanced the production of the AMPs human β-defensin 2 (HBD-2) and TFF3; this effect was inhibited with treatment of G. duodenalis with cysteine protease inhibitors. Collectively, these results suggest that Giardia infections are capable of reducing enteropathogen-induced colitis while increasing production of host AMPs. Additional studies also demonstrated that Giardia was able to directly inhibit the growth of pathogenic bacteria. These results reveal novel mechanisms whereby Giardia may protect against gastrointestinal disease induced by a co-infecting A/E enteropathogen. Our findings shed new light on how microbial-microbial interactions in the gut may protect a host during concomitant infections.

Microwave processing of honey negatively affects honey antibacterial activity by inactivation of bee-derived glucose oxidase and defensin-1.

Science.gov (United States)

Bucekova, Marcela; Juricova, Valeria; Monton, Enrique; Martinotti, Simona; Ranzato, Elia; Majtan, Juraj

2018-02-01

Microwave (MW) thermal heating has been proposed as an efficient method for honey liquefaction, while maintaining honey quality criteria. However, little is known about the effects of MW thermal heating on honey antibacterial activity. In this study, we aimed to determine the effects of MW heating on the antibacterial activity of raw rapeseed honeys against Pseudomonas aeruginosa and Staphylococcus aureus, with a particular focus on two major bee-derived antibacterial components, defensin-1 and hydrogen peroxide (H 2 O 2 ). Our results demonstrated that MW thermal heating completely abolished honey antibacterial activity whereas conventional thermal treatment at 45 and 55°C did not affect the antibacterial activity of honey samples. A significant decrease in both glucose oxidase activity and H 2 O 2 production as well as defensin-1 amount was observed in MW-treated samples. Given that defensin-1 and H 2 O 2 are regular antibacterial components of all honeys, MW heating may have similar negative effects on every type of crystallized/liquid honey. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enzymatic study on AtCCD4 and AtCCD7 and their potential to form acyclic regulatory metabolites

KAUST Repository

Bruno, Mark

2016-09-29

The Arabidopsis carotenoid cleavage dioxygenase 4 (AtCCD4) is a negative regulator of the carotenoid content of seeds and has recently been suggested as a candidate for the generation of retrograde signals that are thought to derive from the cleavage of poly-cis-configured carotene desaturation intermediates. In this work, we investigated the activity of AtCCD4 in vitro and used dynamic modeling to determine its substrate preference. Our results document strict regional specificity for cleavage at the C9–C10 double bond in carotenoids and apocarotenoids, with preference for carotenoid substrates and an obstructing effect on hydroxyl functions, and demonstrate the specificity for all-trans-configured carotenes and xanthophylls. AtCCD4 cleaved substrates with at least one ionone ring and did not convert acyclic carotene desaturation intermediates, independent of their isomeric states. These results do not support a direct involvement of AtCCD4 in generating the supposed regulatory metabolites. In contrast, the strigolactone biosynthetic enzyme AtCCD7 converted 9-cis-configured acyclic carotenes, such as 9-cis-ζ-carotene, 9\\'-cis-neurosporene, and 9-cis-lycopene, yielding 9-cis-configured products and indicating that AtCCD7, rather than AtCCD4, is the candidate for forming acyclic retrograde signals.

Enzymatic study on AtCCD4 and AtCCD7 and their potential to form acyclic regulatory metabolites

KAUST Repository

Bruno, Mark; Koschmieder, Julian; Wuest, Florian; Schaub, Patrick; Fehling-Kaschek, Mirjam; Timmer, Jens; Beyer, Peter; Al-Babili, Salim

2016-01-01

The Arabidopsis carotenoid cleavage dioxygenase 4 (AtCCD4) is a negative regulator of the carotenoid content of seeds and has recently been suggested as a candidate for the generation of retrograde signals that are thought to derive from the cleavage of poly-cis-configured carotene desaturation intermediates. In this work, we investigated the activity of AtCCD4 in vitro and used dynamic modeling to determine its substrate preference. Our results document strict regional specificity for cleavage at the C9–C10 double bond in carotenoids and apocarotenoids, with preference for carotenoid substrates and an obstructing effect on hydroxyl functions, and demonstrate the specificity for all-trans-configured carotenes and xanthophylls. AtCCD4 cleaved substrates with at least one ionone ring and did not convert acyclic carotene desaturation intermediates, independent of their isomeric states. These results do not support a direct involvement of AtCCD4 in generating the supposed regulatory metabolites. In contrast, the strigolactone biosynthetic enzyme AtCCD7 converted 9-cis-configured acyclic carotenes, such as 9-cis-ζ-carotene, 9'-cis-neurosporene, and 9-cis-lycopene, yielding 9-cis-configured products and indicating that AtCCD7, rather than AtCCD4, is the candidate for forming acyclic retrograde signals.

Enzymatic study on AtCCD4 and AtCCD7 and their potential to form acyclic regulatory metabolites

Science.gov (United States)

Bruno, Mark; Koschmieder, Julian; Wuest, Florian; Schaub, Patrick; Fehling-Kaschek, Mirjam; Timmer, Jens; Beyer, Peter; Al-Babili, Salim

2016-01-01

The Arabidopsis carotenoid cleavage dioxygenase 4 (AtCCD4) is a negative regulator of the carotenoid content of seeds and has recently been suggested as a candidate for the generation of retrograde signals that are thought to derive from the cleavage of poly-cis-configured carotene desaturation intermediates. In this work, we investigated the activity of AtCCD4 in vitro and used dynamic modeling to determine its substrate preference. Our results document strict regional specificity for cleavage at the C9–C10 double bond in carotenoids and apocarotenoids, with preference for carotenoid substrates and an obstructing effect on hydroxyl functions, and demonstrate the specificity for all-trans-configured carotenes and xanthophylls. AtCCD4 cleaved substrates with at least one ionone ring and did not convert acyclic carotene desaturation intermediates, independent of their isomeric states. These results do not support a direct involvement of AtCCD4 in generating the supposed regulatory metabolites. In contrast, the strigolactone biosynthetic enzyme AtCCD7 converted 9-cis-configured acyclic carotenes, such as 9-cis-ζ-carotene, 9'-cis-neurosporene, and 9-cis-lycopene, yielding 9-cis-configured products and indicating that AtCCD7, rather than AtCCD4, is the candidate for forming acyclic retrograde signals. PMID:27811075

Staphylococcus aureus resistance to human defensins and evasion of neutrophil killing via the novel virulence factor MprF is based on modification of membrane lipids with L-lysine

NARCIS (Netherlands)

Peschel, A.; Jack, R.W.; Otto, M.; Collins, L.V.; Staubitz, P.; Nicholson, G.; Kalbacher, H.; Nieuwenhuizen, W.F.; Jung, G.; Tarkowski, A.; Kessel, K.P.M. van; Strijp, J.A.G. van

2001-01-01

Defensins, antimicrobial peptides of the innate immune system, protect human mucosal epithelia and skin against microbial infections and are produced in large amounts by neutrophils. The bacterial pathogen Staphylococcus aureus is insensitive to defensins by virtue of an unknown resistance

Acyclic retinoid in chemoprevention of hepatocellular carcinoma: Targeting phosphorylated retinoid X receptor-α for prevention of liver carcinogenesis

Directory of Open Access Journals (Sweden)

Masahito Shimizu

2012-01-01

Full Text Available One of the key features of hepatocellular carcinoma (HCC is the high rate of intrahepatic recurrence that correlates with poor prognosis. Therefore, in order to improve the clinical outcome for patients with HCC, development of a chemopreventive agent that can decrease or delay the incidence of recurrence is a critical issue for urgent investigation. Acyclic retinoid (ACR, a synthetic retinoid, successfully improves HCC patient survival by preventing recurrence and the formation of secondary tumors. A malfunction of the retinoid X receptor-α (RXRα due to phosphorylation by the Ras-MAPK signaling pathway plays a critical role in liver carcinogenesis, and ACR exerts chemopreventive effects on HCC development by inhibiting RXRα phosphorylation. Here, we review the relationship between retinoid signaling abnormalities and liver disease, the mechanisms of how RXRα phosphorylation contributes to liver carcinogenesis, and the detailed effects of ACR on preventing HCC development, especially based on the results of our basic and clinical research. We also outline the concept of "clonal deletion and inhibition" therapy, which is defined as the removal and inhibition of latent malignant clones from the liver before they expand into clinically detectable HCC, because ACR prevents the development of HCC by implementing this concept. Looking toward the future, we discuss "combination chemoprevention" using ACR as a key drug since it can generate a synergistic effect, and may thus be an effective new strategy for the prevention of HCC.

Acyclic nucleoside phosphonate antivirals activate gene expression of monocyte chemotactic protein 1 and 3.

Czech Academy of Sciences Publication Activity Database

Potměšil, Petr; Holý, Antonín; Kmoníčková, Eva; Křížková, Jana; Zídek, Zdeněk

2007-01-01

Roč. 14, č. 1 (2007), s. 59-66 ISSN 1021-7770 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z40550506 Keywords : Acyclic nucleoside phosponate * HIV * Monocyte chemotactic protein Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.024, year: 2007

The preparation of 3-H-labeled Acyclic Nucleoside Phosphonates and Study of their Stability

Czech Academy of Sciences Publication Activity Database

Elbert, Tomáš; Břehová, Petra; Holý, Antonín

2010-01-01

Roč. 75, č. 7 (2010), s. 757-766 ISSN 0010-0765 R&D Projects: GA MŠk 1M0508; GA AV ČR IAA400550801 Institutional research plan: CEZ:AV0Z40550506 Keywords : tritium * 3-H NMR * acyclic nucleotide analogues Subject RIV: CC - Organic Chemistry Impact factor: 0.853, year: 2010

Synthesis, spectroscopic and biological activities studies of acyclic and macrocyclic mono and binuclear metal complexes containing a hard-soft Schiff base.

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Abou-Hussein, Azza A A; Linert, Wolfgang

2012-09-01

Mono- and bi-nuclear acyclic and macrocyclic complexes with hard-soft Schiff base, H(2)L, ligand derived from the reaction of 4,6-diacetylresorcinol and thiocabohydrazide, in the molar ratio 1:2 have been prepared. The H(2)L ligand reacts with Co(II), Ni(II), Cu(II), Zn(II), Mn(II) and UO(2)(VI) nitrates, VO(IV) sulfate and Ru(III) chloride to get acyclic binuclear complexes except for VO(IV) and Ru(III) which gave acyclic mono-nuclear complexes. Reaction of the acyclic mono-nuclear VO(IV) and Ru(III) complexes with 4,6-diacetylresorcinol afforded the corresponding macrocyclic mono-nuclear VO(IV) and Ru(IIII) complexes. Template reactions of the 4,6-diacetylresorcinol and thiocarbohydrazide with either VO(IV) or Ru(III) salts afforded the macrocyclic binuclear VO(IV) and Ru(III) complexes. The Schiff base, H(2)L, ligand acts as dibasic with two NSO-tridentate sites and can coordinate with two metal ions to form binuclear complexes after the deprotonation of the hydrogen atoms of the phenolic groups in all the complexes, except in the case of the acyclic mononuclear Ru(III) and VO(IV) complexes, where the Schiff base behaves as neutral tetradentate chelate with N(2)S(2) donor atoms. The ligands and the metal complexes were characterized by elemental analysis, IR, UV-vis (1)H-NMR, thermal gravimetric analysis (TGA) and ESR, as well as the measurements of conductivity and magnetic moments at room temperature. Electronic spectra and magnetic moments of the complexes indicate the geometries of the metal centers are either tetrahedral, square planar or octahedral. Kinetic and thermodynamic parameters were calculated using Coats-Redfern equation, for the different thermal decomposition steps of the complexes. The ligands and the metal complexes were screened for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria, and Pseudomonas fluorescens as Gram-negative bacteria in addition to Fusarium oxysporum fungus. Most of the complexes exhibit

Structural and functional studies of a phosphatidic acid-binding antifungal plant defensin MtDef4: Identification of an RGFRRR motif governing fungal cell entry

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Sagaram, Uma S.; El-Mounadi, Kaoutar; Buchko, Garry W.; Berg, Howard R.; Kaur, Jagdeep; Pandurangi, Raghoottama; Smith, Thomas J.; Shah, Dilip

2013-12-04

A highly conserved plant defensin MtDef4 potently inhibits the growth of a filamentous fungus Fusarium graminearum. MtDef4 is internalized by cells of F. graminearum. To determine its mechanism of fungal cell entry and antifungal action, NMR solution structure of MtDef4 has been determined. The analysis of its structure has revealed a positively charged patch on the surface of the protein consisting of arginine residues in its γ-core signature, a major determinant of the antifungal activity of MtDef4. Here, we report functional analysis of the RGFRRR motif of the γ-core signature of MtDef4. The replacement of RGFRRR to AAAARR or to RGFRAA not only abolishes fungal cell entry but also results in loss of the antifungal activity of MtDef4. MtDef4 binds strongly to phosphatidic acid (PA), a precursor for the biosynthesis of membrane phospholipids and a signaling lipid known to recruit cytosolic proteins to membranes. Mutations of RGFRRR which abolish fungal cell entry of MtDef4 also impair its binding to PA. Our results suggest that RGFRRR motif is a translocation signal for entry of MtDef4 into fungal cells and that this positively charged motif likely mediates interaction of this defensin with PA as part of its antifungal action.

Association of beta-Defensin Copy Number and Psoriasis in Three Cohorts of European Origin

NARCIS (Netherlands)

Stuart, P.E.; Huffmeier, U.; Nair, R.P.; Palla, R.; Tejasvi, T.; Schalkwijk, J.; Elder, J.T.; Reis, A.; Armour, J.A.

2012-01-01

A single previous study has demonstrated significant association of psoriasis with copy number of beta-defensin genes, using DNA from psoriasis cases and controls from Nijmegen and Erlangen. In this study, we attempted to replicate that finding in larger new cohorts from Erlangen (N=2,017) and

Allelic recombination between distinct genomic locations generates copy number diversity in human β-defensins

Science.gov (United States)

Bakar, Suhaili Abu; Hollox, Edward J.; Armour, John A. L.

2009-01-01

β-Defensins are small secreted antimicrobial and signaling peptides involved in the innate immune response of vertebrates. In humans, a cluster of at least 7 of these genes shows extensive copy number variation, with a diploid copy number commonly ranging between 2 and 7. Using a genetic mapping approach, we show that this cluster is at not 1 but 2 distinct genomic loci ≈5 Mb apart on chromosome band 8p23.1, contradicting the most recent genome assembly. We also demonstrate that the predominant mechanism of change in β-defensin copy number is simple allelic recombination occurring in the interval between the 2 distinct genomic loci for these genes. In 416 meiotic transmissions, we observe 3 events creating a haplotype copy number not found in the parent, equivalent to a germ-line rate of copy number change of ≈0.7% per gamete. This places it among the fastest-changing copy number variants currently known. PMID:19131514

Design and Synthesis of Fluorescent Acyclic Nucleoside Phosphonates as Potent Inhibitors of Bacterial Adenylate Cyclases

Czech Academy of Sciences Publication Activity Database

Břehová, Petra; Šmídková, Markéta; Skácel, Jan; Dračínský, Martin; Mertlíková-Kaiserová, Helena; Velasquez, M. P. S.; Watts, V. J.; Janeba, Zlatko

2016-01-01

Roč. 11, č. 22 (2016), s. 2534-2546 ISSN 1860-7179 R&D Projects: GA MV VG20102015046; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : adenylate cyclase toxin * acyclic nucleoside phosphonates * anthranilic acid Subject RIV: CC - Organic Chemistry Impact factor: 3.225, year: 2016

Acyclic Ketones in the Defensive Secretion of a “Daddy Longlegs” (Leiobunum vittatum)

Science.gov (United States)

Meinwald, J.; Kluge, A. F.; Carrel, J. E.; Eisner, T.

1971-01-01

The defensive secretion of the “daddy longlegs” Leiobunum vittatum was analyzed and found to contain the acyclic ketones 4-methylheptan-3-one and E-4,6-dimethyl-6-octen-3-one as its major organic components. Although 4-methylheptan-3-one has been found previously as an alarm substance in certain ant genera, the second component, whose structure is confirmed by synthesis, is new. PMID:5283937

Investigating temporary acyclicity in a captive group of Asian elephants (Elephas maximus): Relationship between management, adrenal activity and social factors.

Science.gov (United States)

Edwards, Katie L; Trotter, Jessica; Jones, Martin; Brown, Janine L; Steinmetz, Hanspeter W; Walker, Susan L

2016-01-01

Routine faecal steroid monitoring has been used to aid the management of five captive Asian elephant (Elephas maximus) females at Chester Zoo, UK, since 2007. Progestagen analysis initially revealed synchronised oestrous cycles among all females. However, a 14- to 20-week period of temporary acyclicity subsequently occurred in three females, following several management changes (increased training, foot-care and intermittent matriarch removal for health reasons) and the initiation of pregnancy in another female. The aim of this study was to retrospectively investigate whether these management changes were related to increased adrenal activity and disruption of ovarian activity, or whether social factors may have been involved in the temporary cessation of cyclicity. Faecal samples collected every other day were analysed to investigate whether glucocorticoid metabolites were related to reproductive status (pregnant, cycling, acyclic) or management (training, foot-care, matriarch presence). Routine training and foot-care were not associated with adrenal activity; however, intensive foot-care to treat an abscess in one female was associated with increased glucocorticoid concentration. Matriarch presence influenced adrenal activity in three females, being lower when the matriarch was separated from the group at night compared to being always present. However, in the females that exhibited temporary acyclicity, there was no consistent relationship between glucocorticoids and cyclicity state. Although the results of this study do not fully explain this occurrence, the highly synchronised nature of oestrous cycles within this group, and the concurrent acyclicity in three females, raises the question of whether social factors could have been involved in the temporary disruption of ovarian activity. Copyright © 2015 Elsevier Inc. All rights reserved.

Identification and partial characterisation of new members of the Ixodes ricinus defensin family

Czech Academy of Sciences Publication Activity Database

Tonk, Miray; Cabezas Cruz, Alejandro; Valdés, James J.; Rego, Ryan O. M.; Rudenko, Natalia; Golovchenko, Maryna; Bell-Sakyi, L.; de la Fuente, J.; Grubhoffer, Libor

2014-01-01

Roč. 540, č. 2 (2014), s. 146-152 ISSN 0378-1119 R&D Projects: GA ČR(CZ) GAP302/11/1901; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : antimicrobial peptide * defensin * Ixodes ricinus * tick * tick cell line Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.138, year: 2014

Diversification of defensins and NLRs in Arabidopsis species by different evolutionary mechanisms.

Science.gov (United States)

Mondragón-Palomino, Mariana; Stam, Remco; John-Arputharaj, Ajay; Dresselhaus, Thomas

2017-12-15

Genes encoding proteins underlying host-pathogen co-evolution and which are selected for new resistance specificities frequently are under positive selection, a process that maintains diversity. Here, we tested the contribution of natural selection, recombination and transcriptional divergence to the evolutionary diversification of the plant defensins superfamily in three Arabidopsis species. The intracellular NOD-like receptor (NLR) family was used for comparison because positive selection has been well documented in its members. Similar to defensins, NLRs are encoded by a large and polymorphic gene family and many of their members are involved in the immune response. Gene trees of Arabidopsis defensins (DEFLs) show a high prevalence of clades containing orthologs. This indicates that their diversity dates back to a common ancestor and species-specific duplications did not significantly contribute to gene family expansion. DEFLs are characterized by a pervasive pattern of neutral evolution with infrequent positive and negative selection as well as recombination. In comparison, most NLR alignment groups are characterized by frequent occurrence of positive selection and recombination in their leucine-rich repeat (LRR) domain as well negative selection in their nucleotide-binding (NB-ARC) domain. While major NLR subgroups are expressed in pistils and leaves both in presence or absence of pathogen infection, the members of DEFL alignment groups are predominantly transcribed in pistils. Furthermore, conserved groups of NLRs and DEFLs are differentially expressed in response to Fusarium graminearum regardless of whether these genes are under positive selection or not. The present analyses of NLRs expands previous studies in Arabidopsis thaliana and highlights contrasting patterns of purifying and diversifying selection affecting different gene regions. DEFL genes show a different evolutionary trend, with fewer recombination events and significantly fewer instances of

The efficient synthesis of 2-arylpyrimidine acyclic nucleoside phosphonates using Liebeskind-Srogl cross-coupling reaction

Czech Academy of Sciences Publication Activity Database

Břehová, Petra; Česnek, Michal; Dračínský, Martin; Holý, Antonín; Janeba, Zlatko

2011-01-01

Roč. 67, č. 38 (2011), s. 7379-7385 ISSN 0040-4020 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : Liebeskind-Srogl cross - coupling * acyclic nucleoside phosphonates * pyrimidines * arylboronic acids * microwave Subject RIV: CC - Organic Chemistry Impact factor: 3.025, year: 2011

Human β-Defensin 3 Reduces TNF-α-Induced Inflammation and Monocyte Adhesion in Human Umbilical Vein Endothelial Cells

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Tianying Bian

2017-01-01

Full Text Available The aim of this study was to investigate the role of human β-defensin 3 (hBD3 in the initiation stage of atherosclerosis with human umbilical vein endothelial cells (HUVECs triggered by tumor necrosis factor- (TNF- α. The effects of hBD3 on TNF-α-induced endothelial injury and inflammatory response were evaluated. Our data revealed that first, hBD3 reduced the production of interleukin-6 (IL-6, IL-8, monocyte chemoattractant protein-1 (MCP-1, and macrophage migration inhibitory factor (MIF in HUVECs in a dose-dependent manner. In addition, hBD3 significantly prevented intracellular reactive oxygen species (ROS production by HUVECs. Second, western blot analysis demonstrated that hBD3 dose-dependently suppressed the protein levels of intracellular adhesion molecule-1 (ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1 in TNF-α-induced HUVECs. As a result, hBD3 inhibited monocyte adhesion to TNF-α-treated endothelial cells. Additionally, hBD3 suppressed TNF-α-induced F-actin reorganization in HUVECs. Third, hBD3 markedly inhibited NF-κB activation by decreasing the phosphorylation of IKK-α/β, IκB, and p65 subunit within 30 min. Moreover, the phosphorylation of p38 and c-Jun N-terminal protein kinase (JNK in the mitogen-activated protein kinase (MAPK pathway were also inhibited by hBD3 in HUVECs. In conclusion, hBD3 exerts anti-inflammatory and antioxidative effects in endothelial cells in response to TNF-α by inhibiting NF-κB and MAPK signaling.

Synthesis of alpha-Branched Acyclic Nucleoside Phosphonates as Potential Inhibitors of Bacterial Adenylate Cyclases

Czech Academy of Sciences Publication Activity Database

Frydrych, Jan; Skácel, Jan; Šmídková, Markéta; Mertlíková-Kaiserová, Helena; Dračínský, Martin; Gnanasekaran, Ramachandran; Lepšík, Martin; Soto-Velasquez, M.; Watts, V. J.; Janeba, Zlatko

2018-01-01

Roč. 13, č. 2 (2018), s. 199-206 ISSN 1860-7179 R&D Projects: GA MV VG20102015046; GA ČR(CZ) GBP208/12/G016; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * adenylate cyclase toxin * bisamidates * Bordetella pertussis * prodrugs Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 3.225, year: 2016

Expression of beta-defensins pBD-1 and pBD-2 along the small tract of the pig: Lack of upregulation in vivo upon Salmonella typhimurium infection

NARCIS (Netherlands)

Veldhuizen, E.J.; Dijk, van A.; Tersteeg, M.H.; Kalkhove, S.I.; Meulen, van der J.; Niewold, T.A.; Haagsman, H.P.

2007-01-01

Defensins are antimicrobial peptides that play an important role in the innate immune response in the intestine. Up to date, only one ß-defensin (pBD-1), has been described in pig, which was found to be expressed at low levels in the intestine. We set-up a quantitative PCR method to detect the gene

Expression of beta-defensins pBD-1 and pBD-2 along the small intestinal tract of the pig: lack of upregulation in vivo upon Salmonella typhimurium infection.

Science.gov (United States)

Veldhuizen, Edwin J A; van Dijk, Albert; Tersteeg, Monique H G; Kalkhove, Stefanie I C; van der Meulen, Jan; Niewold, Theo A; Haagsman, Henk P

2007-01-01

Defensins are antimicrobial peptides that play an important role in the innate immune response in the intestine. Up to date, only one beta-defensin (pBD-1), has been described in pig, which was found to be expressed at low levels in the intestine. We set-up a quantitative PCR method to detect the gene expression of pBD-1 and a newly discovered porcine beta-defensin, pBD-2. Expression of pBD-1 mRNA increased from the proximal to the distal part of the intestine whereas pBD-2 expression decreased. The main gene expression sites for pBD-2 were kidney and liver, whereas pBD-1 was mainly expressed in tongue. The porcine small intestinal segment perfusion (SISP) technique was used to investigate effects of Salmonella typhimurium DT104 on intestinal morphology and pBD-1 and pBD-2 mRNA levels in vivo. The early responses were studied 2, 4 and 8 h post-infection in four separate jejunal and ileal segments. Immunohistochemistry showed invasion of the mucosa by Salmonella and changes in intestinal morphology. However, no concomitant changes in expression of either pBD-1 or pBD-2 were observed. We conclude that at least two defensins are differentially expressed in the intestine of pigs, and that expression of both defensins is not altered by S. typhimurium under these conditions.

[Study on vaginal production of human defensins and the correlated pathogenetic factors of vulvovaginal candidiasis].

Science.gov (United States)

Wang, Wen; DI, Wen; Liao, Qin-ping; Liu, Zhao-hui; Zhang, Ning; Zhang, Hui-ying; Zhang, Dai; Geng, Li; Fan, Shang-rong; Hu, Li-na

2008-07-01

To investigate the correlated pathogenetic factors and vaginal local immunity in vulvovaginal candidiasis (VVC). A case control study was conducted to compare VVC group (60 cases) with normal group (60 cases). All of the women filled up the specific questionnaires. Routine examination, pH test and bacterial culture were done on the vaginal discharge. Cytokines of the vaginal lavage were measured by enzyme linked immunosorbent assay. (1) Outcomes of the questionnaires: there was no significant difference between the two groups in educational background, knowledge of gynecologic infection, history of gynecologic infection, hygienic habit, sex life, or use of medicine (P > 0.05). The incidence of chronic cervicitis in normal group (43%, 26/60) was higher than in VVC group (22%, 13/60; P vaginal pH between the two groups (P > 0.05). (3) Detection rate of candida albicans by vaginal discharge routine examination was 72% (43/60). (4) The concentrations of interleukin (IL) 2, and IL-4 in vaginal lavage did not show significant difference between the two groups (P > 0.05), but the concentrations of human defensin 5, human beta-defensin (HBD) 1, and HBD2 in VVC group [(0.94 +/- 0.44) mg/L, (3.1 +/- 0.4) microg/L, (10 +/- 6) microg/L] were higher than normal group (P < 0.05). VVC is a common vulvovaginitis. There is no significant correlation between the incidence of VVC and educational background, knowledge of gynecologic infection, history of gynecologic infection, hygienic habit, sex life, or use of medicine in the child-bearing period. Human defensin may be closely correlated with the pathogenesis of VVC.

Functional characterization of two defensin isoforms of the hard tick Ixodes ricinus

Czech Academy of Sciences Publication Activity Database

Chrudimská, Tereza; Slaninová, Jiřina; Rudenko, Natalia; Růžek, Daniel; Grubhoffer, Libor

2011-01-01

Roč. 4, č. 1 (2011), e63 ISSN 1756-3305 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GA206/09/1782; GA ČR GD206/09/H026; GA ČR(CZ) GAP302/11/1901 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z40550506 Keywords : defensin * antimicrobial compounds * Ixodes ricinus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.937, year: 2011

Enhanced Topical and Transdermal Delivery of Antineoplastic and Antiviral Acyclic Nucleoside Phosphonate cPr-PMEDAP

Czech Academy of Sciences Publication Activity Database

Vávrová, K.; Kovaříková, P.; Školová, B.; Líbalová, M.; Roh, J.; Čáp, R.; Holý, Antonín; Hrabálek, A.

2011-01-01

Roč. 28, č. 12 (2011), s. 3105-3115 ISSN 0724-8741 R&D Projects: GA MŠk 1M0508 Grant - others:GA ČR(CZ) GAP207/11/0365 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * antivirals * antineoplastics * permeation enhancer * topical skin application * transdermal delivery Subject RIV: CC - Organic Chemistry Impact factor: 4.093, year: 2011

Structure-Activity Relationships of Acyclic Selenopurine Nucleosides as Antiviral Agents

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Pramod K. Sahu

2017-07-01

Full Text Available A series of acyclic selenopurine nucleosides 3a–f and 4a–g were synthesized based on the bioisosteric rationale between oxygen and selenium, and then evaluated for antiviral activity. Among the compounds tested, seleno-acyclovir (4a exhibited the most potent anti-herpes simplex virus (HSV-1 (EC50 = 1.47 µM and HSV-2 (EC50 = 6.34 µM activities without cytotoxicity up to 100 µM, while 2,6-diaminopurine derivatives 4e–g exhibited significant anti-human cytomegalovirus (HCMV activity, which is slightly more potent than the guanine derivative 4d, indicating that they might act as prodrugs of seleno-ganciclovir (4d.

The mycorrhiza-dependent defensin MtDefMd1 of Medicago truncatula acts during the late restructuring stages of arbuscule-containing cells.

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Marian Uhe

Full Text Available Different symbiotic and pathogenic plant-microbe interactions involve the production of cysteine-rich antimicrobial defensins. In Medicago truncatula, the expression of four MtDefMd genes, encoding arbuscular mycorrhiza-dependent defensins containing an N-terminal signal peptide and exhibiting some differences to non-symbiotic defensins, raised over the time of fungal colonization. Whereas the MtDefMd1 and MtDefMd2 promoters were inactive in cells containing young arbuscules, cells with fully developed arbuscules displayed different levels of promoter activities, indicating an up-regulation towards later stages of arbuscule formation. MtDefMd1 and MtDefMd2 expression was absent or strongly down-regulated in mycorrhized ram1-1 and pt4-2 mutants, known for defects in arbuscule branching or premature arbuscule degeneration, respectively. A ~97% knock-down of MtDefMd1/MtDefMd2 expression did not significantly affect arbuscule size. Although overexpression of MtDefMd1 in arbuscule-containing cells led to an up-regulation of MtRam1, encoding a key transcriptional regulator of arbuscule formation, no morphological changes were evident. Co-localization of an MtDefMd1-mGFP6 fusion with additional, subcellular markers revealed that this defensin is associated with arbuscules in later stages of their life-cycle. MtDefMd1-mGFP6 was detected in cells with older arbuscules about to collapse, and ultimately in vacuolar compartments. Comparisons with mycorrhized roots expressing a tonoplast marker indicated that MtDefMd1 acts during late restructuring processes of arbuscule-containing cells, upon their transition into a post-symbiotic state.

Reaction of acyclic enaminones with methoxymethylene meldrum's acid: synthetic and structural implications

OpenAIRE

Cunha,Silvio; Silva,Viviane C. da; Napolitano,Hamilton B.; Lariucci,Carlito; Vencato,Ivo

2003-01-01

The reaction of acyclic enaminones with methoxymethylene Meldrum's acid afforded N-adduct and/or C-adduct of enaminones in moderate to good yields. The regiochemistry of this reaction depends on the N-amino substituent of the enaminone. The C-adduct is a precursor to 2-pyridones. X-ray analysis of two N-adducts were investigated and the Z-s-Z configuration assigned. A reação de enaminonas com o derivado metoximetilênico do ácido de Meldrum forneceu N-adutos e/ou C-adutos das enaminonas, em...

Interaction of phosphates of the acyclic nucleoside phosphonates with nucleoside diphosphate kinase from yeast and bovine liver

Czech Academy of Sciences Publication Activity Database

Horská, Květoslava; Votruba, Ivan; Holý, Antonín

2006-01-01

Roč. 71, č. 1 (2006), s. 35-43 ISSN 0010-0765 R&D Projects: GA AV ČR(CZ) IBS4055109 Institutional research plan: CEZ:AV0Z40550506 Keywords : enzymatic phosphorylation * acyclic nucleotide analogs * NTP analogues Subject RIV: CC - Organic Chemistry Impact factor: 0.881, year: 2006

Measurement methods and accuracy in copy number variation: failure to replicate associations of beta-defensin copy number with Crohn's disease

Science.gov (United States)

Aldhous, Marian C.; Abu Bakar, Suhaili; Prescott, Natalie J.; Palla, Raquel; Soo, Kimberley; Mansfield, John C.; Mathew, Christopher G.; Satsangi, Jack; Armour, John A.L.

2010-01-01

The copy number variation in beta-defensin genes on human chromosome 8 has been proposed to underlie susceptibility to inflammatory disorders, but presents considerable challenges for accurate typing on the scale required for adequately powered case–control studies. In this work, we have used accurate methods of copy number typing based on the paralogue ratio test (PRT) to assess beta-defensin copy number in more than 1500 UK DNA samples including more than 1000 cases of Crohn's disease. A subset of 625 samples was typed using both PRT-based methods and standard real-time PCR methods, from which direct comparisons highlight potentially serious shortcomings of a real-time PCR assay for typing this variant. Comparing our PRT-based results with two previous studies based only on real-time PCR, we find no evidence to support the reported association of Crohn's disease with either low or high beta-defensin copy number; furthermore, it is noteworthy that there are disagreements between different studies on the observed frequency distribution of copy number states among European controls. We suggest safeguards to be adopted in assessing and reporting the accuracy of copy number measurement, with particular emphasis on integer clustering of results, to avoid reporting of spurious associations in future case–control studies. PMID:20858604

Identification of structural traits that increase the antimicrobial activity of a chimeric peptide of human β-defensins 2 and 3.

Science.gov (United States)

Spudy, Björn; Sönnichsen, Frank D; Waetzig, Georg H; Grötzinger, Joachim; Jung, Sascha

2012-10-12

Antimicrobial peptides participate in the first line of defence of many organisms against pathogens. In humans, the family of β-defensins plays a pivotal role in innate immunity. Two human β-defensins, β-defensin-2 and -3 (HBD2 and HBD3), show substantial sequence identity and structural similarity. However, HBD3 kills Staphylococcus (S.) aureus with a 4- to 8-fold higher efficiency compared to HBD2, whereas their activities against Escherichia (E.) coli are very similar. The generation of six HBD2/HBD3-chimeric molecules led to the identification of distinct molecular regions which mediate their divergent killing properties. One of the chimeras (chimera C3) killed both E. coli and S. aureus with an even higher efficacy compared to the wild-type molecules. Due to the broad spectrum of its antimicrobial activity against many human multidrug-resistant pathogens, this HBD2/HBD3-chimeric peptide represents a promising candidate for a new class of antibiotics. In order to investigate the structural basis of its exceptional antimicrobial activity, the peptide's tertiary structure was determined by NMR spectroscopy, which allowed its direct comparison to the published structures of HBD2 and HBD3 and the identification of the activity-increasing molecular features. Copyright © 2012 Elsevier Inc. All rights reserved.

Measurement methods and accuracy in copy number variation: failure to replicate associations of beta-defensin copy number with Crohn's disease.

Science.gov (United States)

Aldhous, Marian C; Abu Bakar, Suhaili; Prescott, Natalie J; Palla, Raquel; Soo, Kimberley; Mansfield, John C; Mathew, Christopher G; Satsangi, Jack; Armour, John A L

2010-12-15

The copy number variation in beta-defensin genes on human chromosome 8 has been proposed to underlie susceptibility to inflammatory disorders, but presents considerable challenges for accurate typing on the scale required for adequately powered case-control studies. In this work, we have used accurate methods of copy number typing based on the paralogue ratio test (PRT) to assess beta-defensin copy number in more than 1500 UK DNA samples including more than 1000 cases of Crohn's disease. A subset of 625 samples was typed using both PRT-based methods and standard real-time PCR methods, from which direct comparisons highlight potentially serious shortcomings of a real-time PCR assay for typing this variant. Comparing our PRT-based results with two previous studies based only on real-time PCR, we find no evidence to support the reported association of Crohn's disease with either low or high beta-defensin copy number; furthermore, it is noteworthy that there are disagreements between different studies on the observed frequency distribution of copy number states among European controls. We suggest safeguards to be adopted in assessing and reporting the accuracy of copy number measurement, with particular emphasis on integer clustering of results, to avoid reporting of spurious associations in future case-control studies.

Acyclic nucleoside bisphosphonates: Synthesis and properties of chiral 2-amino-4,6-bis[(phosphonomethoxy)alkoxy]pyrimidines

Czech Academy of Sciences Publication Activity Database

Doláková, Petra; Dračínský, Martin; Masojídková, Milena; Šolínová, Veronika; Kašička, Václav; Holý, Antonín

2009-01-01

Roč. 44, č. 6 (2009), s. 2408-2424 ISSN 0223-5234 R&D Projects: GA MŠk 1M0508 Grant - others:NIH(US) 1UC1AIO62540-01 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * pyrimidine * bisphosphonates Subject RIV: CC - Organic Chemistry Impact factor: 3.269, year: 2009

The Yin and Yang of human beta defensins in health and disease

Directory of Open Access Journals (Sweden)

Aaron eWeinberg

2012-10-01

Full Text Available Rapidly evolving research examining the extended role of human beta-defensins (hBDs in chemoattraction, innate immune-mediated response and promotion of angiogenesis suggest that the collective effects of hBDs extend well beyond their antimicrobial mechanism(s. Indeed, the numerous basic cellular functions associated with hBDs demonstrate that these peptides have dual impact on health, as they may be advantageous under certain conditions, but potentially detrimental in others. The consequences of these functions are reflected in the overexpression of hBDs in diseases, such as psoriasis, and recently the association of hBDs with pro-tumoral signaling. The mechanisms regulating hBD response in health and disease are still being elucidated. Clearly the spectrum of function now attributed to hBD regulation identifies these molecules as important cellular regulators, whose appropriate expression is critical for proper immune surveillance; i.e., expression of hBDs in proximity to areas of cellular dysregulation may inadvertently exacerbate disease progression. Understanding the mechanism(s that regulate contextual signaling of hBDs is an important area of concentration in our laboratories. Using a combination of immunologic, biochemical and molecular biologic approaches, we have identified signaling pathways associated with hBD promotion of immune homeostasis and have begun to dissect the inappropriate role that beta-defensins may assume in disease.

Acid-Labile Acyclic Cucurbit[n]uril Molecular Containers for Controlled Release.

Science.gov (United States)

Mao, Dake; Liang, Yajun; Liu, Yamin; Zhou, Xianhao; Ma, Jiaqi; Jiang, Biao; Liu, Jia; Ma, Da

2017-10-02

Stimuli-responsive molecular containers are of great importance for controlled drug delivery and other biomedical applications. A new type of acid labile acyclic cucurbit[n]uril (CB[n]) molecular containers is presented that can degrade and release the encapsulated cargo at accelerated rates under mildly acidic conditions (pH 5.5-6.5). These containers retain the excellent recognition properties of CB[n]-type hosts. A cell culture study demonstrated that the cellular uptake of cargos could be fine-tuned by complexation with different containers. The release and cell uptake of cargo dye was promoted by acidic pH. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Defensin from the ornate sheep tick Dermacentor marginatus and its effect on Lyme borreliosis spirochetes

Czech Academy of Sciences Publication Activity Database

Chrudimská, Tereza; Čeřovský, Václav; Slaninová, Jiřina; Rego, Ryan O. M.; Grubhoffer, Libor

2014-01-01

Roč. 46, č. 2 (2014), s. 165-170 ISSN 0145-305X R&D Projects: GA ČR(CZ) GAP302/11/1901 Institutional support: RVO:60077344 ; RVO:61388963 Keywords : Tick * Dermacentor marginatus * Defensin * Borrelia afzelii * Antimicrobial activity * Peptide synthesis Subject RIV: EE - Microbiology, Virology; EE - Microbiology, Virology (UOCHB-X) Impact factor: 2.815, year: 2014

The Alpha-Defensin Immunoassay and Leukocyte Esterase Colorimetric Strip Test for the Diagnosis of Periprosthetic Infection

Science.gov (United States)

Wyatt, M.C.; Beswick, A.D.; Kunutsor, S.K.; Wilson, M.J.; Whitehouse, M.R.; Blom, A.W.

2016-01-01

Background: Synovial biomarkers have recently been adopted as diagnostic tools for periprosthetic joint infection (PJI), but their utility is uncertain. The purpose of this systematic review and meta-analysis was to synthesize the evidence on the accuracy of the alpha-defensin immunoassay and leukocyte esterase colorimetric strip test for the diagnosis of PJI compared with the Musculoskeletal Infection Society diagnostic criteria. Methods: We performed a systematic review to identify diagnostic technique studies evaluating the accuracy of alpha-defensin or leukocyte esterase in the diagnosis of PJI. MEDLINE and Embase on Ovid, ACM, ADS, arXiv, CERN DS (Conseil Européen pour la Recherche Nucléaire Document Server), CrossRef DOI (Digital Object Identifier), DBLP (Digital Bibliography & Library Project), Espacenet, Google Scholar, Gutenberg, HighWire, IEEE Xplore (Institute of Electrical and Electronics Engineers digital library), INSPIRE, JSTOR (Journal Storage), OAlster (Open Archives Initiative Protocol for Metadata Harvesting), Open Content, Pubget, PubMed, and Web of Science were searched for appropriate studies indexed from inception until May 30, 2015, along with unpublished or gray literature. The classification of studies and data extraction were performed independently by 2 reviewers. Data extraction permitted meta-analysis of sensitivity and specificity with construction of receiver operating characteristic curves for each test. Results: We included 11 eligible studies. The pooled diagnostic sensitivity and specificity of alpha-defensin (6 studies) for PJI were 1.00 (95% confidence interval [CI], 0.82 to 1.00) and 0.96 (95% CI, 0.89 to 0.99), respectively. The area under the curve (AUC) for alpha-defensin and PJI was 0.99 (95% CI, 0.98 to 1.00). The pooled diagnostic sensitivity and specificity of leukocyte esterase (5 studies) for PJI were 0.81 (95% CI, 0.49 to 0.95) and 0.97 (95% CI, 0.82 to 0.99), respectively. The AUC for leukocyte esterase and PJI

Oxytocin promotes bone formation during the alveolar healing process in old acyclic female rats.

Science.gov (United States)

Colli, Vilma Clemi; Okamoto, Roberta; Spritzer, Poli Mara; Dornelles, Rita Cássia Menegati

2012-09-01

OT was reported to be a direct regulator of bone mass in young rodents, and this anabolic effect on bone is a peripheral action of OT. The goal of this study was to investigate the peripheral action of oxytocin (OT) in the alveolar healing process in old female rats. Females Wistar rats (24-month-old) in permanent diestrus phase, received two ip (12h apart) injections of saline (NaCl 0.15M - control group) or OT (45μg/rat - treated group). Seven days later, the right maxillary incisor was extracted and analyses were performed up to 28 days of the alveolar healing process (35 days after saline or OT administration). Calcium and phosphorus plasma concentrations did not differ between the groups. The plasma biochemical bone formations markers, alkaline phosphatase (ALP) and osteocalcin were significantly higher in the treated group. Histomorphometric analyses confirmed bone formation as the treated group presented the highest mean value of post-extraction bone formation. Tartrate-resistant acid phosphatase (TRAP) was significantly reduced in the treated group indicating an anti-resorptive effect of OT. Immunohistochemistry reactions performed in order to identify the presence of osteocalcin and TRAP in the bone cells of the dental socket confirmed these outcomes. OT was found to promote bone formation and to inhibit bone resorption in old acyclic female rats during the alveolar healing process. Published by Elsevier Ltd.

Vitamin D Signaling Through Induction of Paneth Cell Defensins Maintains Gut Microbiota and Improves Metabolic Disorders and Hepatic Steatosis in Animal Models

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Danmei Su

2016-11-01

Full Text Available Metabolic syndrome (MetS, characterized as obesity, insulin resistance, and non-alcoholic fatty liver diseases (NAFLD，is associated with vitamin D insufficiency/deficiency in epidemiological studies, while the underlying mechanism is poorly addressed. On the other hand, disorder of gut microbiota, namely dysbiosis, is known to cause MetS and NAFLD. It is also known that systemic inflammation blocks insulin signaling pathways, leading to insulin resistance and glucose intolerance, which are the driving force for hepatic steatosis. Vitamin D receptor (VDR is highly expressed in the ileum of the small intestine，which prompted us to test a hypothesis that vitamin D signaling may determine the enterotype of gut microbiota through regulating the intestinal interface. Here, we demonstrate that high-fat-diet feeding (HFD is necessary but not sufficient, while additional vitamin D deficiency (VDD as a second hit is needed, to induce robust insulin resistance and fatty liver. Under the two hits (HFD+VDD, the Paneth cell-specific alpha-defensins including α-defensin 5 (DEFA5, MMP7 which activates the pro-defensins, as well as tight junction genes, and MUC2 are all suppressed in the ileum, resulting in mucosal collapse, increased gut permeability, dysbiosis, endotoxemia, systemic inflammation which underlie insulin resistance and hepatic steatosis. Moreover, under the vitamin D deficient high fat feeding (HFD+VDD, Helicobacter hepaticus, a known murine hepatic-pathogen, is substantially amplified in the ileum, while Akkermansia muciniphila, a beneficial symbiotic, is diminished. Likewise, the VD receptor (VDR knockout mice exhibit similar phenotypes, showing down regulation of alpha-defensins and MMP7 in the ileum, increased Helicobacter hepaticus and suppressed Akkermansia muciniphila. Remarkably, oral administration of DEFA5 restored eubiosys, showing suppression of Helicobacter hepaticus and increase of Akkermansia muciniphila in association with

Structural and functional studies of a phosphatidic acid-binding antifungal plant defensin MtDef4: identification of an RGFRRR motif governing fungal cell entry.

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Uma Shankar Sagaram

Full Text Available MtDef4 is a 47-amino acid cysteine-rich evolutionary conserved defensin from a model legume Medicago truncatula. It is an apoplast-localized plant defense protein that inhibits the growth of the ascomycetous fungal pathogen Fusarium graminearum in vitro at micromolar concentrations. Little is known about the mechanisms by which MtDef4 mediates its antifungal activity. In this study, we show that MtDef4 rapidly permeabilizes fungal plasma membrane and is internalized by the fungal cells where it accumulates in the cytoplasm. Furthermore, analysis of the structure of MtDef4 reveals the presence of a positively charged γ-core motif composed of β2 and β3 strands connected by a positively charged RGFRRR loop. Replacement of the RGFRRR sequence with AAAARR or RGFRAA abolishes the ability of MtDef4 to enter fungal cells, suggesting that the RGFRRR loop is a translocation signal required for the internalization of the protein. MtDef4 binds to phosphatidic acid (PA, a precursor for the biosynthesis of membrane phospholipids and a signaling lipid known to recruit cytosolic proteins to membranes. Amino acid substitutions in the RGFRRR sequence which abolish the ability of MtDef4 to enter fungal cells also impair its ability to bind PA. These findings suggest that MtDef4 is a novel antifungal plant defensin capable of entering into fungal cells and affecting intracellular targets and that these processes are mediated by the highly conserved cationic RGFRRR loop via its interaction with PA.

Comparative reactivity of different types of stable cyclic and acyclic mono- and diamino carbenes with simple organic substrates.

Science.gov (United States)

Martin, David; Canac, Yves; Lavallo, Vincent; Bertrand, Guy

2014-04-02

A series of stable carbenes, featuring a broad range of electronic properties, were reacted with simple organic substrates. The N,N-dimesityl imidazolylidene (NHC) does not react with isocyanides, whereas anti-Bredt di(amino)carbene (pyr-NHC), cyclic (alkyl)(amino)carbene (CAAC), acyclic di(amino)carbene (ADAC), and acyclic (alkyl)(amino)carbene (AAAC) give rise to the corresponding ketenimines. NHCs are known to promote the benzoin condensation, and we found that the CAAC, pyr-NHC, and ADAC react with benzaldehyde to give the ketone tautomer of the Breslow intermediate, whereas the AAAC first gives the corresponding epoxide and ultimately the Breslow intermediate, which can be isolated. Addition of excess benzaldehyde to the latter does not lead to benzoin but to a stable 1,3-dioxolane. Depending on the electronic properties of carbenes, different products are also obtained with methyl acrylate as a substrate. The critical role of the carbene electrophilicity on the outcome of reactions is discussed.

Characterization of E and Z isomers in macrocyclic lactones and acyclic pheromones by NMR spectra

International Nuclear Information System (INIS)

Mahajan, J.R.; Resck, I.S.; Braz Filho, R.; Carvalho, M.G. de

1995-01-01

A large proportion of pheromones, isolated from a variety of insects, constitutes a big list of diversely functionalized acyclic compounds, which have been synthesized by several routes. Catalytic or chemical methods were examined for the Z to E isomerization and their efficiency checked by 1 H and 13 C NMR spectra. Nuclear magnetic resonance has been used to identify and characterize molecular structure of the compounds, besides chemical shifts was analysed

Comparison of the nodule vs. root transcriptome of the actinorhizal plant Datisca glomerata: actinorhizal nodules contain a specific class of defensins.

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Irina V Demina

Full Text Available Actinorhizal root nodule symbioses are very diverse, and the symbiosis of Datisca glomerata has previously been shown to have many unusual aspects. In order to gain molecular information on the infection mechanism, nodule development and nodule metabolism, we compared the transcriptomes of D. glomerata roots and nodules. Root and nodule libraries representing the 3'-ends of cDNAs were subjected to high-throughput parallel 454 sequencing. To identify the corresponding genes and to improve the assembly, Illumina sequencing of the nodule transcriptome was performed as well. The evaluation revealed 406 differentially regulated genes, 295 of which (72.7% could be assigned a function based on homology. Analysis of the nodule transcriptome showed that genes encoding components of the common symbiosis signaling pathway were present in nodules of D. glomerata, which in combination with the previously established function of SymRK in D. glomerata nodulation suggests that this pathway is also active in actinorhizal Cucurbitales. Furthermore, comparison of the D. glomerata nodule transcriptome with nodule transcriptomes from actinorhizal Fagales revealed a new subgroup of nodule-specific defensins that might play a role specific to actinorhizal symbioses. The D. glomerata members of this defensin subgroup contain an acidic C-terminal domain that was never found in plant defensins before.

Association studies of the copy-number variable ß-defensin cluster on 8p23.1 in adenocarcinoma and chronic pancreatitis

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Taudien Stefan

2012-11-01

Full Text Available Abstract Background Human ß-defensins are a family of antimicrobial peptides located at the mucosal surface. Both sequence multi-site variations (MSV and copy-number variants (CNV of the defensin-encoding genes are associated with increased risk for various diseases, including cancer and inflammatory conditions such as psoriasis and acute pancreatitis. In a case–control study, we investigated the association between MSV in DEFB104 as well as defensin gene (DEF cluster copy number (CN, and pancreatic ductal adenocarcinoma (PDAC and chronic pancreatitis (CP. Results Two groups of PDAC (N=70 and CP (N=60 patients were compared to matched healthy control groups CARLA1 (N=232 and CARLA2 (N=160, respectively. Four DEFB104 MSV were haplotyped by PCR, cloning and sequencing. DEF cluster CN was determined by multiplex ligation-dependent probe amplification. Neither the PDAC nor the CP cohorts show significant differences in the DEFB104 haplotype distribution compared to the respective control groups CARLA1 and CARLA2, respectively. The diploid DEF cluster CN exhibit a significantly different distribution between PDAC and CARLA1 (Fisher’s exact test P=0.027, but not between CP and CARLA2 (P=0.867. Conclusion Different DEF cluster b CN distribution between PDAC patients and healthy controls indicate a potential protective effect of higher CNs against the disease.

Structural basis of metallo-β-lactamase, serine-β-lactamase and penicillin-binding protein inhibition by cyclic boronates

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Brem, Jürgen; Cain, Ricky; Cahill, Samuel; McDonough, Michael A.; Clifton, Ian J.; Jiménez-Castellanos, Juan-Carlos; Avison, Matthew B.; Spencer, James; Fishwick, Colin W. G.; Schofield, Christopher J.

2016-08-01

β-Lactamases enable resistance to almost all β-lactam antibiotics. Pioneering work revealed that acyclic boronic acids can act as `transition state analogue' inhibitors of nucleophilic serine enzymes, including serine-β-lactamases. Here we report biochemical and biophysical analyses revealing that cyclic boronates potently inhibit both nucleophilic serine and zinc-dependent β-lactamases by a mechanism involving mimicking of the common tetrahedral intermediate. Cyclic boronates also potently inhibit the non-essential penicillin-binding protein PBP 5 by the same mechanism of action. The results open the way for development of dual action inhibitors effective against both serine- and metallo-β-lactamases, and which could also have antimicrobial activity through inhibition of PBPs.

Antibacterial Activity of Four Human Beta-Defensins: HBD-19, HBD-23, HBD-27, and HBD-29

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David Camerini

2012-03-01

Full Text Available Human β-defensins (HBD are a family of small antimicrobial peptides that play important roles in the innate and adaptive immune defenses against microbial infection. In this study, we predicted the mature sequences and assessed the antibacterial properties of synthetic HBD-19, HBD-23, HBD-27, and HBD-29 against three species of clinically relevant bacteria: Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. We also examined the cytotoxicity of each β-defensin to human cells. HBD-19 exhibited modest antibacterial effects against E. coli and S. aureus but had little effect on the growth of P. aeruginosa. HBD-23 exhibited substantial antibacterial effects against all three bacterial species and was particularly potent against the Gram-negative species, E. coli and P. aeruginosa. HBD-27 exerted modest antibacterial activity only towards S. aureus while HBD-29 had modest antibacterial activity for E. coli and P. aeruginosa. HBD-23 and HBD-27 showed little or no toxicity to human peripheral blood mononuclear cells, while HBD-19 and HBD-29 decreased cell viability by 20% at 30 μg/mL.

Comparing the efficiency of Er,Cr:YSGG laser and diode laser on human β-defensin-1 and IL-1β levels during the treatment of generalized aggressive periodontitis and chronic periodontitis.

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Ertugrul, Abdullah Seckin; Tekin, Yasin; Talmac, Ahmet Cemil

2017-11-01

The aim of this study is to determine the suitability of the Er,Cr:YSGG and 940 ± 15-nm diode laser for the treatment of generalized aggressive periodontitis and chronic periodontitis by measuring the levels of human β-defensin-1 and IL-1β. A total of 26 patients were included in this study. The study was designed as a "split-mouth" experiment. We performed scaling and root planing in the right maxillary quadrant, scaling and root planning + Er,Cr:YSGG laser in the left maxillary quadrant, scaling and root planning + 940 ± 15-nm diode laser in the left mandibular quadrant, and only scaling and root planing in the right mandibular quadrant. The presence of human β-defensin-1 and IL-1β was analyzed with an ELISA. When the baseline and post-treatment human β-defensin-1 levels and IL-1β levels of the study groups were evaluated, a decrease in human β-defensin-1 and IL-1β were observed in the quadrant where the Er,Cr:YSGG laser was applied in both the generalized aggressive periodontitis group and the chronic periodontitis group. The use of the Er,Cr:YSGG laser at non-surgical periodontal treatment decreased both IL-1β and human β-defensin-1 levels. It is likely that Er,Cr:YSGG laser is more suitable for the treatment of generalized aggressive periodontitis and chronic periodontitis.

Synthesis and Evaluation of Novel Acyclic Nucleoside Phosphonates as Inhibitors of Plasmodium falciparum and Human 6-Oxopurine Phosphoribosyltransferases

Czech Academy of Sciences Publication Activity Database

Kaiser, Martin Maxmilian; Hocková, Dana; Wang, T. H.; Dračínský, Martin; Poštová Slavětínská, Lenka; Procházková, Eliška; Edstein, M. D.; Chavchich, M.; Keough, D. T.; Guddat, L. W.; Janeba, Zlatko

2015-01-01

Roč. 10, č. 10 (2015), s. 1707-1723 ISSN 1860-7179 R&D Projects: GA MV VG20102015046; GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : 6-oxopurine * acyclic nucleoside phosphonates * phosphoribosyltransferases * malaria * phosphoramidates Subject RIV: CC - Organic Chemistry Impact factor: 2.980, year: 2015

NMR studies of abasic sites in DNA duplexes: Deoxyadenosine stacks into the helix opposite acyclic lesions

International Nuclear Information System (INIS)

Kalnik, M.W.; Chang, Chienneng; Johnson, F.; Grollman, A.P.; Patel, D.J.

1989-01-01

Proton and phosphorus NMR studies are reported for two complementary nonanucleotide duplexes containing acyclic abasic sites. The first duplex, d(C-A-T-G-A-G-T-A-C)·d(G-T-A-C-P-C-A-T-G), contains an acyclic propanyl moiety, P, located opposite a deoxyadenosine at the center of the helix (designated AP P 9-mer duplex). The second duplex, d(C-A-T-G-A-G-T-A-C-)·d(G-T-A-C-E-C-A-T-G), contains a similarly located acyclic ethanyl moiety, E (designated AP E 9-mer duplex). The ethanyl moiety is one carbon shorter than the natural carbon-phosphodiester backbone of a single nucleotide unit of DNA. The majority of the exchangeable and nonexchangeable base and sugar protons in both the AP P 9-mer and AP E 9-mer duplexes, including those at the abasic site, have been assigned by recording and analyzing two-dimensional phase-sensitive NOESY data sets in H 2 O and D 2 O solution between -5 and 5 degree C. These spectroscopic observations establish that A5 inserts into the helix opposite the abasic site (P14 and El14) and stacks between the flanking G4·C15 and G6·C13 Watson-Crick base pairs in both the AP P 9-mer and AP E 9-mer duplexes. Proton NMR parameters for the Ap P 9-mer and AP E 9-mer duplexes are similar to those reported previously. These proton NMR experiments demonstrate that the structures at abasic sites are very similar whether the five-membered ring is open or closed or whether the phosphodiester backbone is shortened by one carbon atom. Phosphorus spectra of the AP P 9-mer and AP E 9-mer duplexes (5 degree C) indicate that the backbone conformation is similarly perturbed at three phosphodiester backbone torsion angles

Eosinophils from patients with type 1 diabetes mellitus express high level of myeloid alpha-defensins and myeloperoxidase

Czech Academy of Sciences Publication Activity Database

Neuwirth, Aleš; Dobeš, Jan; Oujezdská, Jana; Ballek, Ondřej; Benešová, Martina; Sumnik, Z.; Včeláková, J.; Koloušková, S.; Obermannová, B.; Kolář, Michal; Štechová, K.; Filipp, Dominik

2012-01-01

Roč. 273, č. 2 (2012), s. 158-163 ISSN 0008-8749 R&D Projects: GA MŠk 2B08066 Institutional research plan: CEZ:AV0Z50520514 Keywords : type 1 diabetes * alpha-defensin * myeloperoxidase * granulocyte * eosinophil Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.743, year: 2012

Association of β-defensin copy number and psoriasis in three cohorts of European origin.

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Stuart, Philip E; Hüffmeier, Ulrike; Nair, Rajan P; Palla, Raquel; Tejasvi, Trilokraj; Schalkwijk, Joost; Elder, James T; Reis, Andre; Armour, John A L

2012-10-01

A single previous study has demonstrated significant association of psoriasis with copy number of β-defensin genes, using DNA from psoriasis cases and controls from Nijmegen and Erlangen. In this study, we attempted to replicate that finding in larger new cohorts from Erlangen (N=2,017) and Michigan (N=5,412), using improved methods for β-defensin copy number determination based on the paralog ratio test, and enhanced methods of analysis and association testing implemented in the CNVtools resource. We demonstrate that the association with psoriasis found in the discovery sample is maintained after applying improved typing and analysis methods (P=5.5 × 10(-4), odds ratio (OR)=1.25). We also find that the association is replicated in 2,616 cases and 2,526 controls from Michigan, although at reduced significance (P=0.014), but not in new samples from Erlangen (1,396 cases and 621 controls, P=0.38). Meta-analysis across all cohorts suggests a nominally significant association (P=6.6 × 10(-3)/2 × 10(-4)) with an effect size (OR=1.081) much lower than found in the discovery study (OR=1.32). This reduced effect size and significance on replication is consistent with a genuine but weak association.

Association of β-defensin copy number and psoriasis in three cohorts of European origin

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Stuart, Philip E; Hüffmeier, Ulrike; Nair, Rajan P; Palla, Raquel; Tejasvi, Trilokraj; Schalkwijk, Joost; Elder, James T; Reis, Andre; Armour, John AL

2012-01-01

A single previous study has demonstrated significant association of psoriasis with copy number of beta-defensin genes, using DNA from psoriasis cases and controls from Nijmegen and Erlangen. In this study we attempted to replicate that finding in larger new cohorts from Erlangen (N = 2017) and Michigan (N = 5412), using improved methods for beta-defensin copy number determination based on the paralog ratio test (PRT), and enhanced methods of analysis and association testing implemented in the CNVtools resource. We demonstrate that the association with psoriasis found in the discovery sample is maintained after applying improved typing and analysis methods (p = 5.5 × 10−4, OR = 1.25). We also find that the association is replicated in 2616 cases and 2526 controls from Michigan, although at reduced significance (p = 0.014), but not in new samples from Erlangen (1396 cases and 621 controls, p = 0.38). Meta-analysis across all cohorts suggests a nominally significant association (p = 6.6 × 10−3/2 × 10−4) with an effect size (OR = 1.081) much lower than found in the discovery study (OR = 1.32). This reduced effect size and significance on replication is consistent with a genuine but weak association. PMID:22739795

Enantiopurity analysis of new types of acyclic nucleoside phosphonates by capillary electrophoresis with cyclodextrins as chiral selectors

Czech Academy of Sciences Publication Activity Database

Šolínová, Veronika; Kaiser, Martin Maxmilian; Lukáč, Miloš; Janeba, Zlatko; Kašička, Václav

2014-01-01

Roč. 37, č. 3 (2014), s. 295-303 ISSN 1615-9306 R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR(CZ) GA13-17224S; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * CE * chiral analysis * cyclodextrins * nucleotide analogs Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.737, year: 2014

Influence of Acyclic Nucleoside Phosphonate Antivirals on Gene Expression of Chemokine Receptors CCR5 and CXCR4

Czech Academy of Sciences Publication Activity Database

Potměšil, P.; Holý, Antonín; Zídek, Zdeněk

2015-01-01

Roč. 61, č. 1 (2015), s. 1-7 ISSN 0015-5500 R&D Projects: GA ČR GA305/03/1470; GA MŠk 1M0508 Institutional support: RVO:61388963 ; RVO:68378041 Keywords : acyclic nucleoside phosphonate * HIV * CCR5 * CXCR4 * cytokine * RT-PCR Subject RIV: CC - Organic Chemistry; FR - Pharmacology ; Medidal Chemistry (UEM-P) Impact factor: 0.833, year: 2015

Learning directed acyclic graphs from large-scale genomics data.

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Nikolay, Fabio; Pesavento, Marius; Kritikos, George; Typas, Nassos

2017-09-20

In this paper, we consider the problem of learning the genetic interaction map, i.e., the topology of a directed acyclic graph (DAG) of genetic interactions from noisy double-knockout (DK) data. Based on a set of well-established biological interaction models, we detect and classify the interactions between genes. We propose a novel linear integer optimization program called the Genetic-Interactions-Detector (GENIE) to identify the complex biological dependencies among genes and to compute the DAG topology that matches the DK measurements best. Furthermore, we extend the GENIE program by incorporating genetic interaction profile (GI-profile) data to further enhance the detection performance. In addition, we propose a sequential scalability technique for large sets of genes under study, in order to provide statistically significant results for real measurement data. Finally, we show via numeric simulations that the GENIE program and the GI-profile data extended GENIE (GI-GENIE) program clearly outperform the conventional techniques and present real data results for our proposed sequential scalability technique.

C/EBPβ Promotes Immunity to Oral Candidiasis through Regulation of β-Defensins.

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Simpson-Abelson, Michelle R; Childs, Erin E; Ferreira, M Carolina; Bishu, Shrinivas; Conti, Heather R; Gaffen, Sarah L

2015-01-01

Humans or mice subjected to immunosuppression, such as corticosteroids or anti-cytokine biologic therapies, are susceptible to mucosal infections by the commensal fungus Candida albicans. Recently it has become evident that the Th17/IL-17 axis is essential for immunity to candidiasis, but the downstream events that control immunity to this fungus are poorly understood. The CCAAT/Enhancer Binding Protein-β (C/EBPβ) transcription factor is important for signaling by multiple inflammatory stimuli, including IL-17. C/EBPβ is regulated in a variety of ways by IL-17, and controls several downstream IL-17 target genes. However, the role of C/EBPβ in vivo is poorly understood, in part because C/EBPβ-deficient mice are challenging to breed and work with. In this study, we sought to understand the role of C/EBPβ in the context of an IL-17-dependent immune response, using C. albicans infection as a model system. Confirming prior findings, we found that C/EBPβ is required for immunity to systemic candidiasis. In contrast, C/EBPβ(-/-) mice were resistant to oropharyngeal candidiasis (OPC), in a manner indistinguishable from immunocompetent WT mice. However, C/EBPβ(-/-) mice experienced more severe OPC than WT mice in the context of cortisone-induced immunosuppression. Expression of the antimicrobial peptide β-defensin (BD)-3 correlated strongly with susceptibility in C/EBPβ(-/-) mice, but no other IL-17-dependent genes were associated with susceptibility. Therefore, C/EBPβ contributes to immunity to mucosal candidiasis during cortisone immunosuppression in a manner linked to β-defensin 3 expression, but is apparently dispensable for the IL-17-dependent response.

Human β-defensin 2 may inhibit internalisation of bacillus Calmette-Guérin (BCG) in bladder cancer cells.

Science.gov (United States)

Kim, Jung Hoon; Kim, Soon-Ja; Lee, Kyung Mee; Chang, In Ho

2013-10-01

To investigate whether secretion of human β-defensin 2 (HBD-2) is induced by bacillus Calmette-Guérin (BCG) and to determine whether HBD-2 affects BCG internalisation in bladder cancer cells. Reverse transcription-polymerase chain reaction analysis was used to determine whether HBD-2 mRNA increases after incubation with BCG. HBD-2 proteins in 5637 and T24 human bladder cancer cell lines were assayed by enzyme-linked immunosorbent assay. The internalisation rate was evaluated by double immunofluorescence assay and confocal microscopy to test the optimal dose of HBD-2 for BCG internalisation. We also investigated the difference in internalisation rates and cell viability between recombinant HBD-2 protein, anti-HBD-2 antibody, and HBD-2 plus anti-HBD-2 antibody pretreatments. BCG induced HBD-2 mRNA expression and HBD-2 production dose and time-dependently in bladder cancer cells and affected BCG internalisation. Pretreatment with recombinant HBD-2 protein lowered internalisation of BCG dose-dependently. Moreover, anti-HBD-2 antibody prevented the effect of HBD-2 on BCG internalisation in bladder cancer cells. The internalisation rate of BCG pretreated with anti-HBD-2 antibody was higher than that in the control in 5637 (P internalisation rate in cells pretreated with anti-HBD-2 antibody plus recombinant HBD-2 protein was higher than that in the control in 5637 (P internalisation, which plays an important role during the initiation and propagation of the immunotherapeutic response in bladder cancer cells. © 2013 The Authors. BJU International © 2013 BJU International.

Rhodium-Catalyzed Insertion Reaction of PhP Group of Pentaphenylcyclopentaphosphine with Acyclic and Cyclic Disulfides.

Science.gov (United States)

Arisawa, Mieko; Sawahata, Kyosuke; Yamada, Tomoki; Sarkar, Debayan; Yamaguchi, Masahiko

2018-02-16

Organophosphorus compounds with a phosphorus atom attached to a phenyl group and two organothio/organoseleno groups were synthesized using the rhodium-catalyzed insertion reaction of the PhP group of pentaphenylcyclopentaphosphine (PhP) 5 with acyclic disulfides and diselenides. The method was applied to the synthesis of heterocyclic compounds containing the S-P-S group by the reaction of (PhP) 5 and cyclic disulfides such as 1,2-dithietes, 1,2-dithiocane, 1,4,5-dithiopane, and 1,2-dithiolanes.

Antiprotozoan and Antiviral Activities of Non-Cytotoxic Truncated and Variant Analogues of Mussel Defensin

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Philippe Roch

2004-01-01

Full Text Available We previously reported the crucial role displayed by loop 3 of defensin isolated from the Mediterranean mussel, Mytilus galloprovincialis, in antibacterial and antifungal activities. We now investigated antiprotozoan and antiviral activities of some previously reported fragments B, D, E, P and Q. Two fragments (D and P efficiently killed Trypanosoma brucei (ID50 4–12 μM and Leishmania major (ID50 12–45 μM in a time/dose-dependent manner. Killing of T. brucei started as early as 1 h after initiation of contact with fragment D and reached 55% mortality after 6 h. Killing was temperature dependent and a temperature of 4°C efficiently impaired the ability to kill T. brucei. Fragments bound to the entire external epithelium of T. brucei. Prevention of HIV-1 infestation was obtained only with fragments P and Q at 20 μM. Even if fragment P was active on both targets, the specificity of fragments D and Q suggest that antiprotozoan and antiviral activities are mediated by different mechanisms. Truncated sequences of mussel defensin, including amino acid replacement to maintain 3D structure and increased positive net charge, also possess antiprotozoan and antiviral capabilities. New alternative and/or complementary antibiotics can be derived from the vast reservoir of natural antimicrobial peptides (AMPs contained in marine invertebrates.

The Effect of Calcipotriol on the Expression of Human β Defensin-2 and LL-37 in Cultured Human Keratinocytes

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Beom Joon Kim

2009-01-01

Full Text Available Background. Vitamin D has been reported to regulate innate immunity by controlling the expression of antimicrobial peptides (AMPs. Objective. We investigated the effect of calcipotriol on the expression of AMPs in human cultured keratinocytes. Methods. Keratinocytes were treated with lipopolysaccharide (LPS, TNF-α, Calcipotriol and irradiated with UVB, cultured, and harvested. To assess the expression of human beta defensin-2 and LL-37 in the control group, not exposed to any stimulants, the experimental group was treated with LPS, TNF-α, or UVB, and another group was treated again with calcipotriol; reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemical staining were performed. Results. In the experimental group treated with LPS, UVB irradiation, and TNF-α, the expression of β-defensin and LL-37 was increased more than in the control group and then decreased in the experimental group treated with calcipotriol. Conclusions. Calcipotriol suppressed HBD-2 and LL-37, which were stimulated by UVB, LPS, and TNF-α.

Effect of yoghurt containing Bifidobacterium lactis Bb12® on faecal excretion of secretory immunoglobulin A and human beta-defensin 2 in healthy adult volunteers

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Kabeerdoss Jayakanthan

2011-12-01

Full Text Available Abstract Background Probiotics are used to provide health benefits. The present study tested the effect of a probiotic yoghurt on faecal output of beta-defensin and immunoglobulin A in a group of young healthy women eating a defined diet. Findings 26 women aged 18-21 (median 19 years residing in a hostel were given 200 ml normal yoghurt every day for a week, followed by probiotic yoghurt containing Bifidobacterium lactis Bb12® (109 in 200 ml for three weeks, followed again by normal yoghurt for four weeks. Stool samples were collected at 0, 4 and 8 weeks and assayed for immunoglobulin A and human beta-defensin-2 by ELISA. All participants tolerated both normal and probiotic yoghurt well. Human beta-defensin-2 levels in faeces were not altered during the course of the study. On the other hand, compared to the basal sample, faecal IgA increased during probiotic feeding (P = 0.0184 and returned to normal after cessation of probiotic yoghurt intake. Conclusions Bifidobacterium lactis Bb12® increased secretory IgA output in faeces. This property may explain the ability of probiotics to prevent gastrointestinal and lower respiratory tract infections.

Synthesis and biological evaluation of acyclic nucleotide analogues with a furo[2,3-d]pyrimidin-2(3H)-one base

Czech Academy of Sciences Publication Activity Database

Janeba, Zlatko; Holý, Antonín; Pohl, Radek; Snoeck, R.; Andrei, G.; De Clercq, E.; Balzarini, J.

2010-01-01

Roč. 88, č. 7 (2010), s. 628-638 ISSN 0008-4042 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * Sonogashira reaction * intramolecular cyclization Subject RIV: CC - Organic Chemistry Impact factor: 1.374, year: 2010

Transplantation of periodontal ligament cell sheets expressing human β-defensin-3 promotes anti-inflammation in a canine model of periodontitis

Science.gov (United States)

Zhu, Minwen; Miao, Bo; Zhu, Jianhua; Wang, Haiyan; Zhou, Zengtong

2017-01-01

Periodontitis is a chronic oral inflammatory disease caused by microorganisms. Human β-defensin-3 (HBD-3) is an endogenous antimicrobial peptide that inhibits a broad spectrum of microorganisms. Cell sheet technology has been widely applied in tissue and organ reconstructions. In the current study, it was aimed to investigate the anti-inflammatory effect of periodontal tissue engineered by HBD-3 gene-modified periodontal ligament cell (PDLC) sheets, and to identify a suitable method of promoting the regeneration of periodontal tissues. Western blot analysis and antimicrobial tests were used to confirm the expression of HBD-3. The effect of the cell sheets on anti-inflammatory activity and bone remodeling in a dog model of periodontitis was demonstrated by immunohistochemistry. The results demonstrated that the transfected PDLCs stably expressed HBD-3. Periodontal pathogens were susceptible to the antimicrobial activity of the cell sheets. In addition, the cell sheets relieved the bone resorption caused by inflammation in the in vivo model. HBD-3 may potentially be applied in the treatment of periodontitis and may function as osteogenic promoter via its anti-inflammatory effect. PMID:28944821

The β-Defensin Gallinacin-6 Is Expressed in the Chicken Digestive Tract and Has Antimicrobial Activity against Food-Borne Pathogens▿

Science.gov (United States)

van Dijk, Albert; Veldhuizen, Edwin J. A.; Kalkhove, Stefanie I. C.; Tjeerdsma-van Bokhoven, Johanna L. M.; Romijn, Roland A.; Haagsman, Henk P.

2007-01-01

Food-borne pathogens are responsible for most cases of food poisoning in developed countries and are often associated with poultry products, including chicken. Little is known about the role of β-defensins in the chicken digestive tract and their efficacy. In this study, the expression of chicken β-defensin gallinacin-6 (Gal-6) and its antimicrobial activity against food-borne pathogens were investigated. Reverse transcription-PCR analysis showed high expression of Gal-6 mRNA in the esophagus and crop, moderate expression in the glandular stomach, and low expression throughout the intestinal tract. Putative transcription factor binding sites for nuclear factor kappa beta, activator protein 1, and nuclear factor interleukin-6 were found in the Gal-6 gene upstream region, which suggests a possible inducible nature of the Gal-6 gene. In colony-counting assays, strong bactericidal and fungicidal activity was observed, including bactericidal activity against food-borne pathogens Campylobacter jejuni, Salmonella enterica serovar Typhimurium, Clostridium perfringens, and Escherichia coli. Treatment with 16 μg/ml synthetic Gal-6 resulted in a 3 log unit reduction in Clostridium perfringens survival within 60 min, indicating fast killing kinetics. Transmission electron microscopy examination of synthetic-Gal-6-treated Clostridium perfringens cells showed dose-dependent changes in morphology after 30 min, including intracellular granulation, cytoplasm retraction, irregular septum formation in dividing cells, and cell lysis. The high expression in the proximal digestive tract and broad antimicrobial activity suggest that chicken β-defensin gallinacin-6 plays an important role in chicken innate host defense. PMID:17194828

Competitive solvent extraction of alkaline-earth cations into chloroform by lipophilic acyclic polyether dicarboxylic acids

International Nuclear Information System (INIS)

Kang, S.I.; Czech, A.; Czech, B.P.; Stewart, L.E.; Bartsch, R.A.

1985-01-01

Competitive solvent extraction of alkaline-earth cations from aqueous solutions into chloroform by a series of lipophilic acyclic polyether dicarboxylic acids is reported. The influence of polyether chain length and of terminal carboxylic acid group variation upon extraction selectivity and efficiency is assessed. In the competitive extraction of concentrated magnesium, calcium, strontium and barium chloride solutions, one complexing agent exhibits pronounced selectivity for barium with Ba 2+ /S 2+ = 50, Ba 2+ /Ca 2+ = 250, and no detectable Mg 2+ extraction. 20 references, 3 figures, 1 table

Distinct signaling pathways leading to the induction of human β-defensin 2 by stimulating an electrolyticaly-generated acid functional water and double strand RNA in oral epithelial cells.

Science.gov (United States)

Gojoubori, Takahiro; Nishio, Yukina; Asano, Masatake; Nishida, Tetsuya; Komiyama, Kazuo; Ito, Koichi

2014-04-01

Defensins, a major family of cationic antimicrobial peptides, play important roles in innate immunity. In the present study, we investigated whether double-stranded RNA (dsRNA), a by-product of RNA virus replication, can induce human β-defensins-2 (hBD-2) expression in oral epithelial cells (OECs). We also examined the hBD-2-inducible activity of acid-electrolyzed functional water (FW). The results indicated that both dsRNA- and FW-induced hBD-2 expression in OECs. The induction efficiency was much higher for FW than for dsRNA. FW-induced production of hBD-2 was clearly observed by immunofluorescence staining. A luciferase assay was performed with 1.2 kb of the 5'-untranslated region (5'-UTR) of the hBD-2 gene. The results indicated that the nuclear factor-kappa B (NF-κB)-binding site proximal to the translation initiation site was indispensable for dsRNA-stimulated hBD-2 expression, but not in the case of FW. Moreover, FW-stimulated hBD-2 expression did not depend on NF-κB activity; instead, FW inhibited NF-κB activity. Pretreatment of the cells with specific inhibitors against NF-κB further confirmed NF-κB-independent hBD-2 induction by FW. In analogy to the results for intestinal epithelial cells (IECs), the dsRNA signal, but not FW, was sensed by toll-like receptor 3 (TLR3) in OECs. These results suggested that hBD-2 expression induced by dsRNA and FW is regulated by distinct mechanisms in OECs.

Influence of Two Acyclic Homoterpenes (Tetranorterpenes) on the Foraging Behavior of Anthonomus grandis Boh.

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Magalhães, D M; Borges, M; Laumann, R A; Woodcock, C M; Pickett, J A; Birkett, M A; Blassioli-Moraes, Maria Carolina

2016-04-01

Previous studies have shown that the boll weevil, Anthonomus grandis, is attracted to constitutive and conspecific herbivore-induced cotton volatiles, preferring the blend emitted by cotton at the reproductive over the vegetative stage. Moreover, this preference was paralleled by the release of the acyclic homoterpenes (tetranorterpenes) (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) in Delta Opal cotton being higher at the vegetative than at the reproductive stage. Here, we evaluated whether this difference in release of acyclic homoterpenes also occurred in other cotton varieties, and if boll weevils could recognize these compounds as indicators of a specific cotton phenological stage. Results showed that cotton genotypes CNPA TB-90, BRS-293 and Delta Opal all produced higher levels of DMNT and TMTT at the vegetative stage than at the reproductive stage and that these homoterpenes allowed for principal component analysis separation of volatiles produced by the two phenological stages. Electroantennograms confirmed boll weevil antennal responses to DMNT and TMTT. Behavioral assays, using Y-tube olfactometers, showed that adding synthetic homoterpenes to reproductive cotton volatiles (mimicking cotton at the vegetative stage in terms of homoterpene levels) resulted in reduced attraction to boll weevils compared to that to unmodified reproductive cotton. Weevils showed no preference when given a choice between plants at the vegetative stage and the vegetative stage-mimicked plant. Altogether, the results show that DMNT and TMTT are used by boll weevils to distinguish between cotton phenological stages.

The β-defensin gallinacin-6 is expressed in the chicken digestive tract and has antimicrobial activity against food-borne pathogens

NARCIS (Netherlands)

van Dijk, A.; Veldhuizen, E.J.A.; Kalkhove, S.I.C.; Tjeerdsma-van Bokhoven, J.L.M.; Romijn, R.A.; Haagsman, H.P.

2007-01-01

Food-borne pathogens are responsible for most cases of food poisoning in developed countries and are often associated with poultry products, including chicken. Little is known about the role of ß-defensins in the chicken digestive tract and their efficacy. In this study, the expression of chicken

Estimation of apparent binding constant of complexes of selected acyclic nucleoside phosphonates with beta-cyclodextrin by affinity capillary electrophoresis

Czech Academy of Sciences Publication Activity Database

Šolínová, Veronika; Mikysková, Hana; Kaiser, Martin Maxmilian; Janeba, Zlatko; Holý, Antonín; Kašička, Václav

2016-01-01

Roč. 37, č. 2 (2016), s. 239-247 ISSN 0173-0835 R&D Projects: GA ČR(CZ) GA13-17224S; GA ČR(CZ) GA15-01948S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * affinity capillary electrophoresis * binding constant * nucleotide analogs * beta-cyclodextrin Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 2.744, year: 2016

New acyclic secondary metabolites from the biologically active fraction of Albizia lebbeck flowers.

Science.gov (United States)

Al-Massarani, Shaza M; El Gamal, Ali A; Abd El Halim, Mohamed F; Al-Said, Mansour S; Abdel-Kader, Maged S; Basudan, Omer A; Alqasoumi, Saleh I

2017-01-01

The total extract of Albizia lebbeck flowers was examined in vivo for its possible hepatoprotective activity in comparison with the standard drug silymarin at two doses. The higher dose expressed promising activity especially in reducing the levels of AST, ALT and bilirubin. Fractionation via liquid-liquid partition and reexamination of the fractions revealed that the n -butanol fraction was the best in improving liver biochemical parameters followed by the n -hexane fraction. However, serum lipid parameters were best improved with CHCl 3 fraction. The promising biological activity results initiated an intensive chromatographic purification of A. lebbeck flowers fractions. Two compounds were identified from natural source for the first time, the acyclic farnesyl sesquiterpene glycoside1-O-[6-O- α -l-arabinopyranosyl- β -d-glucopyranoside]-(2 E ,6 E -)-farnesol ( 6 ) and the squalene derivative 2,3-dihydroxy-2,3-dihydrosqualene ( 9 ), in addition to eight compounds reported here for the first time from the genus Albizia ; two benzyl glycosides, benzyl 1-O- β -d-glucopyranoside ( 1 ) and benzyl 6-O- α -l-arabinopyranosyl β -d-glucopyranoside ( 2 ); three acyclic monoterpene glycosides, linalyl β -d-glucopyranoside ( 3 ) and linalyl 6-O- α -l-arabinopyranosyl- β -d-glucopyranoside ( 4 ); (2 E )-3,7-dimethylocta-2,6-dienoate-6-O- α -l arabinopyranosyl- β -d-glucopyranoside ( 5 ), two oligoglycosides, n -hexyl- α -l arabinopyranosyl-(1 → 6)- β -d-glucopyranoside (creoside) ( 7 ) and n -octyl α -l-arabinopyranosyl-(1 → 6)- β -d-glucopyranoside (rhodiooctanoside) ( 8 ); and ethyl fructofuranoside ( 10 ). The structures of the isolated compounds were elucidated based on extensive examination of their spectroscopic 1D and 2D-NMR, MS, UV, and IR data. It is worth mentioning that, some of the isolated linalol glycoside derivatives were reported as aroma precursors.

New acyclic secondary metabolites from the biologically active fraction of Albizia lebbeck flowers

Directory of Open Access Journals (Sweden)

Shaza M. Al-Massarani

2017-01-01

Full Text Available The total extract of Albizia lebbeck flowers was examined in vivo for its possible hepatoprotective activity in comparison with the standard drug silymarin at two doses. The higher dose expressed promising activity especially in reducing the levels of AST, ALT and bilirubin. Fractionation via liquid–liquid partition and reexamination of the fractions revealed that the n-butanol fraction was the best in improving liver biochemical parameters followed by the n-hexane fraction. However, serum lipid parameters were best improved with CHCl3 fraction. The promising biological activity results initiated an intensive chromatographic purification of A. lebbeck flowers fractions. Two compounds were identified from natural source for the first time, the acyclic farnesyl sesquiterpene glycoside1-O-[6-O-α-l-arabinopyranosyl-β-d-glucopyranoside]-(2E,6E--farnesol (6 and the squalene derivative 2,3-dihydroxy-2,3-dihydrosqualene (9, in addition to eight compounds reported here for the first time from the genus Albizia; two benzyl glycosides, benzyl 1-O-β-d-glucopyranoside (1 and benzyl 6-O-α-l-arabinopyranosyl β-d-glucopyranoside (2; three acyclic monoterpene glycosides, linalyl β-d-glucopyranoside (3 and linalyl 6-O-α-l-arabinopyranosyl-β-d-glucopyranoside (4; (2E-3,7-dimethylocta-2,6-dienoate-6-O-α-l arabinopyranosyl-β-d-glucopyranoside (5, two oligoglycosides, n-hexyl-α-l arabinopyranosyl-(1 → 6-β-d-glucopyranoside (creoside (7 and n-octyl α-l-arabinopyranosyl-(1 → 6-β-d-glucopyranoside (rhodiooctanoside (8; and ethyl fructofuranoside (10. The structures of the isolated compounds were elucidated based on extensive examination of their spectroscopic 1D and 2D-NMR, MS, UV, and IR data. It is worth mentioning that, some of the isolated linalol glycoside derivatives were reported as aroma precursors.

Acyclic cucurbit[n]uril-type molecular containers: influence of aromatic walls on their function as solubilizing excipients for insoluble drugs.

Science.gov (United States)

Zhang, Ben; Isaacs, Lyle

2014-11-26

We studied the influence of the aromatic sidewalls on the ability of acyclic CB[n]-type molecular containers (1a-1e) to act as solubilizing agents for 19 insoluble drugs including the developmental anticancer agent PBS-1086. All five containers exhibit good water solubility and weak self-association (Ks ≤ 624 M(-1)). We constructed phase solubility diagrams to extract Krel and Ka values for the container·drug complexes. The acyclic CB[n]-type containers generally display significantly higher Ka values than HP-β-CD toward drugs. Containers 1a-1e bind the steroidal ring system and aromatic moieties of insoluble drugs. Compound 1b displays highest affinity toward most of the drugs studied. Containers 1a and 1b are broadly applicable and can be used to formulate a wider variety of insoluble drugs than was previously possible with cyclodextrin technology. For drugs that are solubilized by both HP-β-CD and 1a-1e, lower concentrations of 1a-1e are required to achieve identical [drug].

Theoretic derivation of directed acyclic subgraph algorithm and comparisons with message passing algorithm

Science.gov (United States)

Ha, Jeongmok; Jeong, Hong

2016-07-01

This study investigates the directed acyclic subgraph (DAS) algorithm, which is used to solve discrete labeling problems much more rapidly than other Markov-random-field-based inference methods but at a competitive accuracy. However, the mechanism by which the DAS algorithm simultaneously achieves competitive accuracy and fast execution speed, has not been elucidated by a theoretical derivation. We analyze the DAS algorithm by comparing it with a message passing algorithm. Graphical models, inference methods, and energy-minimization frameworks are compared between DAS and message passing algorithms. Moreover, the performances of DAS and other message passing methods [sum-product belief propagation (BP), max-product BP, and tree-reweighted message passing] are experimentally compared.

1,25-Dihydroxyvitamin-D3 Induces Avian β-Defensin Gene Expression in Chickens.

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Long Zhang

Full Text Available Host defense peptides (HDPs play a critical role in innate immunity. Specific modulation of endogenous HDP synthesis by dietary compounds has been regarded as a novel approach to boost immunity and disease resistance in animal production. 1,25-dihydroxy vitamin D3 (1,25D3 is well known as a powerful HDP inducer in humans, but limited information about the effect of 1,25D3 on HDPs in poultry is available. Here, we sought to examine whether 1,25D3 could stimulate avian β-defensin (AvBD expression in chickens. We used chicken embryo intestinal epithelial cells (CEIEPCs and peripheral blood mononuclear cells (PBMCs to study the effect of 1,25D3 on the expression of AvBDs. We observed that 1,25D3 is able to up-regulate the expression of several AvBDs in CEIEPCs and PBMCs, whereas it increased the amounts of AvBD4 mRNA in CEIEPCs only in the presence of lipopolysaccharide (LPS. On the other hand, LPS treatment not only inhibited the expression of CYP24A1 but also altered the expression pattern of VDR in CEIEPCs. Furthermore, AvBDs were not directly regulated by 1,25D3, as cycloheximide completely blocked 1,25D3-induced expression of AvBDs. Our observations suggest that 1,25D3 is capable of inducing AvBD gene expression and is a potential antibiotic alternative through augmentation of host innate immunity as well as disease control in chickens.

Identification of a cell-penetrating peptide domain from human beta-defensin 3 and characterization of its anti-inflammatory activity

Directory of Open Access Journals (Sweden)

Lee JY

2015-08-01

Full Text Available Jue Yeon Lee,1,* Jin Sook Suh,2,* Jung Min Kim,1 Jeong Hwa Kim,1 Hyun Jung Park,1 Yoon Jeong Park,1,2 Chong Pyoung Chung1 1Central Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC, Chungcheongbuk-do, Republic of Korea; 2Dental Regenerative Biotechnology, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea *These authors contributed equally to this work Abstract: Human beta-defensins (hBDs are crucial factors of intrinsic immunity that function in the immunologic response to a variety of invading enveloped viruses, bacteria, and fungi. hBDs can cause membrane depolarization and cell lysis due to their highly cationic nature. These molecules participate in antimicrobial defenses and the control of adaptive and innate immunity in every mammalian species and are produced by various cell types. The C-terminal 15-mer peptide within hBD3, designated as hBD3-3, was selected for study due to its cell- and skin-penetrating activity, which can induce anti-inflammatory activity in lipopolysaccharide-treated RAW 264.7 macrophages. hBD3-3 penetrated both the outer membrane of the cells and mouse skin within a short treatment period. Two other peptide fragments showed poorer penetration activity compared to hBD3-3. hBD3-3 inhibited the lipopolysaccharide-induced production of inducible nitric oxide synthase, nitric oxide, and secretory cytokines, such as interleukin-6 and tumor necrosis factor in a concentration-dependent manner. Moreover, hBD3-3 reduced the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. Further investigation also revealed that hBD3-3 downregulated nuclear factor kappa B-dependent inflammation by directly suppressing the degradation of phosphorylated-IκBα and by downregulating active nuclear factor kappa B p65. Our findings indicate that hBD3-3 may be conjugated with drugs of interest to ensure their proper translocation to

Acyclic N-halamine-immobilized polyurethane: Preparation and antimicrobial and biofilm-controlling functions

Science.gov (United States)

Luo, Jie; Porteous, Nuala; Lin, Jiajin; Sun, Yuyu

2015-01-01

Hydroxyl groups were introduced onto polyurethane surfaces through 1,6-hexamethylene diisocyanate activation, followed by diethanolamine hydroxylation. Polymethacrylamide was covalently attached to the hydroxylated polyurethane through surface grafting polymerization of methacrylamide using cerium (IV) ammonium nitrate as an initiator. After bleach treatment, the amide groups of the covalently bound polymethacrylamide chains were transformed into N-halamines. The new N-halamine-immobilized polyurethane provided a total sacrifice of 107–108 colony forming units per milliliter of Staphylococcus aureus (Gram-positive bacteria), Escherichia coli (Gram-negative bacteria), and Candida albicans (fungi) within 10 min and successfully prevented bacterial and fungal biofilm formation. The antimicrobial and biofilm-controlling effects were both durable and rechargeable, pointing to great potentials of the new acyclic N-halamine-immobilized polyurethane for a broad range of related applications. PMID:26089593

Consensus pursuit of heterogeneous multi-agent systems under a directed acyclic graph

Science.gov (United States)

Yan, Jing; Guan, Xin-Ping; Luo, Xiao-Yuan

2011-04-01

This paper is concerned with the cooperative target pursuit problem by multiple agents based on directed acyclic graph. The target appears at a random location and moves only when sensed by the agents, and agents will pursue the target once they detect its existence. Since the ability of each agent may be different, we consider the heterogeneous multi-agent systems. According to the topology of the multi-agent systems, a novel consensus-based control law is proposed, where the target and agents are modeled as a leader and followers, respectively. Based on Mason's rule and signal flow graph analysis, the convergence conditions are provided to show that the agents can catch the target in a finite time. Finally, simulation studies are provided to verify the effectiveness of the proposed approach.

Role of urinary cathelicidin LL-37 and human β-defensin 1 in uncomplicated Escherichia coli urinary tract infections

DEFF Research Database (Denmark)

Nielsen, Karen L; Dynesen, Pia; Larsen, Preben

2014-01-01

Cathelicidin (LL-37) and human β-defensin 1 (hBD-1) are important components of the innate defense in the urinary tract. The aim of this study was to characterize whether these peptides are important for developing uncomplicated Escherichia coli urinary tract infections (UTIs). This was investiga......Cathelicidin (LL-37) and human β-defensin 1 (hBD-1) are important components of the innate defense in the urinary tract. The aim of this study was to characterize whether these peptides are important for developing uncomplicated Escherichia coli urinary tract infections (UTIs......). This was investigated by comparing urinary peptide levels of UTI patients during and after infection to those of controls, as well as characterizing the fecal flora of participants with respect to susceptibility to LL-37 and in vivo virulence. Forty-seven UTI patients and 50 controls who had never had a UTI were...... included. Participants were otherwise healthy, premenopausal, adult women. LL-37 MIC levels were compared for fecal E. coli clones from patients and controls and were also compared based on phylotypes (A, B1, B2, and D). In vivo virulence was investigated in the murine UTI model by use of selected fecal...

The synthetic human beta-defensin-3 C15 peptide exhibits antimicrobial activity against Streptococcus mutans, both alone and in combination with dental disinfectants.

Science.gov (United States)

Ahn, Ki Bum; Kim, A Reum; Kum, Kee-Yeon; Yun, Cheol-Heui; Han, Seung Hyun

2017-10-01

Streptococcus mutans is a major etiologic agent of human dental caries that forms biofilms on hard tissues in the human oral cavity, such as tooth and dentinal surfaces. Human β-defensin-3 (HBD3) is a 45-amino-acid natural antimicrobial peptide that has broad spectrum antimicrobial activity against bacteria and fungi. A synthetic peptide consisting of the C-terminal 15 amino acids of HBD3 (HBD3-C15) was recently shown to be sufficient for its antimicrobial activity. Thus, clinical applications of this peptide have garnered attention. In this study, we investigated whether HBD3-C15 inhibits the growth of the representative cariogenic pathogen Streptococcus mutans and its biofilm formation. HBD3-C15 inhibited bacterial growth, exhibited bactericidal activity, and attenuated bacterial biofilm formation in a dose-dependent manner. HBD3-C15 potentiated the bactericidal and anti-biofilm activity of calcium hydroxide (CH) and chlorhexidine digluconate (CHX), which are representative disinfectants used in dental clinics, against S. mutans. Moreover, HBD3-C15 showed antimicrobial activity by inhibiting biofilm formation by S. mutans and other dentinophilic bacteria such as Enterococcus faecalis and Streptococcus gordonii, which are associated with dental caries and endodontic infection, on human dentin slices. These effects were observed for HBD3-C15 alone and for HBD3-C15 in combination with CH or CHX. Therefore, we suggest that HBD3-C15 is a potential alternative or additive disinfectant that can be used for the treatment of oral infectious diseases, including dental caries and endodontic infections.

Expression and antimicrobial function of beta-defensin 1 in the lower urinary tract.

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Brian Becknell

Full Text Available Beta defensins (BDs are cationic peptides with antimicrobial activity that defend epithelial surfaces including the skin, gastrointestinal, and respiratory tracts. However, BD expression and function in the urinary tract are incompletely characterized. The purpose of this study was to describe Beta Defensin-1 (BD-1 expression in the lower urinary tract, regulation by cystitis, and antimicrobial activity toward uropathogenic Escherichia coli (UPEC in vivo. Human DEFB1 and orthologous mouse Defb1 mRNA are detectable in bladder and ureter homogenates, and human BD-1 protein localizes to the urothelium. To determine the relevance of BD-1 to lower urinary tract defense in vivo, we evaluated clearance of UPEC by Defb1 knockout (Defb1(-/- mice. At 6, 18, and 48 hours following transurethral UPEC inoculation, no significant differences were observed in bacterial burden in bladders or kidneys of Defb1(-/- and wild type C57BL/6 mice. In wild type mice, bladder Defb1 mRNA levels decreased as early as two hours post-infection and reached a nadir by six hours. RT-PCR profiling of BDs identified expression of Defb3 and Defb14 mRNA in murine bladder and ureter, which encode for mBD-3 and mBD-14 protein, respectively. MBD-14 protein expression was observed in bladder urothelium following UPEC infection, and both mBD-3 and mBD-14 displayed dose-dependent bactericidal activity toward UPEC in vitro. Thus, whereas mBD-1 deficiency does not alter bladder UPEC burden in vivo, we have identified mBD-3 and mBD-14 as potential mediators of mucosal immunity in the lower urinary tract.

Expression and Antimicrobial Function of Beta-Defensin 1 in the Lower Urinary Tract

Science.gov (United States)

Becknell, Brian; Spencer, John David; Carpenter, Ashley R.; Chen, Xi; Singh, Aspinder; Ploeger, Suzanne; Kline, Jennifer; Ellsworth, Patrick; Li, Birong; Proksch, Ehrhardt; Schwaderer, Andrew L.; Hains, David S.; Justice, Sheryl S.; McHugh, Kirk M.

2013-01-01

Beta defensins (BDs) are cationic peptides with antimicrobial activity that defend epithelial surfaces including the skin, gastrointestinal, and respiratory tracts. However, BD expression and function in the urinary tract are incompletely characterized. The purpose of this study was to describe Beta Defensin-1 (BD-1) expression in the lower urinary tract, regulation by cystitis, and antimicrobial activity toward uropathogenic Escherichia coli (UPEC) in vivo. Human DEFB1 and orthologous mouse Defb1 mRNA are detectable in bladder and ureter homogenates, and human BD-1 protein localizes to the urothelium. To determine the relevance of BD-1 to lower urinary tract defense in vivo, we evaluated clearance of UPEC by Defb1 knockout (Defb1 -/-) mice. At 6, 18, and 48 hours following transurethral UPEC inoculation, no significant differences were observed in bacterial burden in bladders or kidneys of Defb1 -/- and wild type C57BL/6 mice. In wild type mice, bladder Defb1 mRNA levels decreased as early as two hours post-infection and reached a nadir by six hours. RT-PCR profiling of BDs identified expression of Defb3 and Defb14 mRNA in murine bladder and ureter, which encode for mBD-3 and mBD-14 protein, respectively. MBD-14 protein expression was observed in bladder urothelium following UPEC infection, and both mBD-3 and mBD-14 displayed dose-dependent bactericidal activity toward UPEC in vitro. Thus, whereas mBD-1 deficiency does not alter bladder UPEC burden in vivo, we have identified mBD-3 and mBD-14 as potential mediators of mucosal immunity in the lower urinary tract. PMID:24204930

Defensins from the tick Ixodes scapularis are effective against phytopathogenic fungi and the human bacterial pathogen Listeria grayi

Czech Academy of Sciences Publication Activity Database

Tonk, Miray; Cabezas-Cruz, A.; Valdés, James J.; Rego, Ryan O. M.; Chrudimská, Tereza; Strnad, Martin; Šíma, Radek; Bell-Sakyi, L.; Franta, Z.; Vilcinskas, A.; Grubhoffer, Libor; Rahnamaeian, M.

2014-01-01

Roč. 7, DEC 3 2015 (2014), s. 554 ISSN 1756-3305 R&D Projects: GA ČR(CZ) GAP302/11/1901; GA MŠk(CZ) EE2.3.30.0032; GA ČR GP13-12816P Institutional support: RVO:60077344 Keywords : Antimicrobial peptide * Defensin * Listeria grayi * Fusarium spp * Ixodes scapularis * Tick cell line Subject RIV: EE - Microbiology, Virology Impact factor: 3.430, year: 2014

The Arabidopsis mutant iop1 exhibits induced over-expression of the plant defensin gene PDF1.2 and enhanced pathogen resistance

NARCIS (Netherlands)

Penninckx, I.A.M.A.; Eggermont, K.; Schenk, P.M.; Ackerveken, van den G.; Cammue, B.P.A.; Thomma, B.P.H.J.

2003-01-01

Jasmonate and ethylene are concomitantly involved in the induction of the Arabidopsis plant defensin gene PDF1.2. To define genes in the signal transduction pathway leading to the induction of PDF1.2, we screened for mutants with induced over-expression of a β-glucuronidase reporter, under the

Accurate measurement of gene copy number for human alpha-defensin DEFA1A3.

Science.gov (United States)

Khan, Fayeza F; Carpenter, Danielle; Mitchell, Laura; Mansouri, Omniah; Black, Holly A; Tyson, Jess; Armour, John A L

2013-10-20

Multi-allelic copy number variants include examples of extensive variation between individuals in the copy number of important genes, most notably genes involved in immune function. The definition of this variation, and analysis of its impact on function, has been hampered by the technical difficulty of large-scale but accurate typing of genomic copy number. The copy-variable alpha-defensin locus DEFA1A3 on human chromosome 8 commonly varies between 4 and 10 copies per diploid genome, and presents considerable challenges for accurate high-throughput typing. In this study, we developed two paralogue ratio tests and three allelic ratio measurements that, in combination, provide an accurate and scalable method for measurement of DEFA1A3 gene number. We combined information from different measurements in a maximum-likelihood framework which suggests that most samples can be assigned to an integer copy number with high confidence, and applied it to typing 589 unrelated European DNA samples. Typing the members of three-generation pedigrees provided further reassurance that correct integer copy numbers had been assigned. Our results have allowed us to discover that the SNP rs4300027 is strongly associated with DEFA1A3 gene copy number in European samples. We have developed an accurate and robust method for measurement of DEFA1A3 copy number. Interrogation of rs4300027 and associated SNPs in Genome-Wide Association Study SNP data provides no evidence that alpha-defensin copy number is a strong risk factor for phenotypes such as Crohn's disease, type I diabetes, HIV progression and multiple sclerosis.

The expression of cytokines and β -defensin 2, - 3, -4 in rabbit bone tissue after hydroxyapatite (HAp), α- Tricalcium phosphate (α-TCP) and polymethylmethacrylate (PMMA) implantation

International Nuclear Information System (INIS)

Vamze, J; Pilmane, M; Skagers, A

2012-01-01

Bone loss induced by inflammation is one of the complications after biomaterial implantation. There is no much data on expression of cytokines and defensins into the bone tissue around the implants in literature. The aim of this work was to investigate the distribution and appearance of interleukin (IL)-1, IL-6, IL-8, IL-10 and (β - defensin (BD)-2, BD-3, BD-4 after the implantation of different biomaterials. Bone developing zones, signs of bone-implant contact and low expression of pro-inflammatory cytokine IL-1, IL-6 and anti-inflammatory cytokine IL-10 in experimental tissue with pure HAp and unburned HAp implants indicate a potential advantage of this material in terms of its biocompatibility over the other materials used in our study.

The Antimicrobial Peptide Human Beta-Defensin-3 Is Induced by Platelet-Released Growth Factors in Primary Keratinocytes

OpenAIRE

Andreas Bayer; Justus Lammel; Mersedeh Tohidnezhad; Sebastian Lippross; Peter Behrendt; Tim Klüter; Thomas Pufe; Jochen Cremer; Holger Jahr; Franziska Rademacher; Regine Gläser; Jürgen Harder

2017-01-01

Platelet-released growth factors (PRGF) and its related clinically used formulations (e.g., Vivostat Platelet-Rich Fibrin (PRF?)) contain a variety of chemokines, cytokines, and growth factors and are therefore used to support healing of chronic, hard-to-heal, or infected wounds. Human beta-defensin-3 (hBD-3) is an antimicrobial peptide inducibly expressed in human keratinocytes especially upon wounding. The potent antimicrobial activity of hBD-3 together with its wound closure-promoting acti...

Beta-defensins-2 expressions in gingival epithelium cells after probiotic Lactobacillus reuteri induction

Directory of Open Access Journals (Sweden)

Tuti Kusumaningsih

2016-12-01

Full Text Available Background: Beta-defensins (BD are antimicrobial peptides that play a role in defense against pathogens. Beta-defensins (BD are expressed by a variety of epithelial cells, including gingival epithelium, salivary glands, saliva and salivary duct. BD-1 is expressed constitutively, while BD-2 and BD-3 expressions can be induced by commensal bacteria. Probiotics are commensal bacteria, thus L. reuteri as probiotic bacteria may act as “inducer” for BD-2 in epithelial gingiva. S. mutans is the main bacteria causing dental caries and sensitive to BD-2. Purpose: This study was aimed to prove that the administration of probiotic L. reuteri may improve BD-2 expressions in the gingiva epithelium. Method: This study was conducted in vivo using twenty-four male Rattus norvegicus Wistar strains aged 10-12 weeks and weighed 120-150 g. Those rats were randomly divided into four groups, namely negative control group (not induced with L. reuteri or S. mutans, positive control group (induced with S. mutans for 14 days, treatment group 1 (induced with L. reuteri for 14 days and S. mutans for 7 days, and treatment group 2 (induced with L. reuteri and S. mutans for 14 days concurrently. The concentration of L. reuteri used was 4x108cfu/ml, while the concentration of S. mutans was 1x 1010cfu/ml. 0.1 ml of each was dropped in the region of the mandibular incisors. BD-2 expression was calculated using immunohistochemical method. The difference of BD-2 expressions in gingival epithelial cells in the respective groups was analyzed by Anova/SPSS. Results: There were significant differences in BD-2 expressions in gingival epithelial cells in each group based on the results of Anova test (p=0.001. Conclusion: The administration of probiotic L. reuteri is able to increase BD-2 expressions in gingival epithelial cells.

The Alpha-Defensin Immunoassay and Leukocyte Esterase Colorimetric Strip Test for the Diagnosis of Periprosthetic Infection: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Wyatt, M C; Beswick, A D; Kunutsor, S K; Wilson, M J; Whitehouse, M R; Blom, A W

2016-06-15

Synovial biomarkers have recently been adopted as diagnostic tools for periprosthetic joint infection (PJI), but their utility is uncertain. The purpose of this systematic review and meta-analysis was to synthesize the evidence on the accuracy of the alpha-defensin immunoassay and leukocyte esterase colorimetric strip test for the diagnosis of PJI compared with the Musculoskeletal Infection Society diagnostic criteria. We performed a systematic review to identify diagnostic technique studies evaluating the accuracy of alpha-defensin or leukocyte esterase in the diagnosis of PJI. MEDLINE and Embase on Ovid, ACM, ADS, arXiv, CERN DS (Conseil Européen pour la Recherche Nucléaire Document Server), CrossRef DOI (Digital Object Identifier), DBLP (Digital Bibliography & Library Project), Espacenet, Google Scholar, Gutenberg, HighWire, IEEE Xplore (Institute of Electrical and Electronics Engineers digital library), INSPIRE, JSTOR (Journal Storage), OAlster (Open Archives Initiative Protocol for Metadata Harvesting), Open Content, Pubget, PubMed, and Web of Science were searched for appropriate studies indexed from inception until May 30, 2015, along with unpublished or gray literature. The classification of studies and data extraction were performed independently by 2 reviewers. Data extraction permitted meta-analysis of sensitivity and specificity with construction of receiver operating characteristic curves for each test. We included 11 eligible studies. The pooled diagnostic sensitivity and specificity of alpha-defensin (6 studies) for PJI were 1.00 (95% confidence interval [CI], 0.82 to 1.00) and 0.96 (95% CI, 0.89 to 0.99), respectively. The area under the curve (AUC) for alpha-defensin and PJI was 0.99 (95% CI, 0.98 to 1.00). The pooled diagnostic sensitivity and specificity of leukocyte esterase (5 studies) for PJI were 0.81 (95% CI, 0.49 to 0.95) and 0.97 (95% CI, 0.82 to 0.99), respectively. The AUC for leukocyte esterase and PJI was 0.97 (95% CI, 0.95 to 0

Antiviral activities of 2,6-diaminopurine-based acyclic nucleoside phosphonates against herpesviruses: In vitro study results with pseudorabies virus (PrV, SuHV-1)

Czech Academy of Sciences Publication Activity Database

Zouharová, D.; Lipenská, I.; Fojtiková, M.; Kulich, P.; Neca, J.; Slaný, M.; Kovařčík, K.; Turanek-Knotigová, P.; Hubatka, F.; Celechovská, H.; Mašek, J.; Koudelka, Š.; Procházka, L.; Eyer, L.; Plocková, J.; Bartheldyová, E.; Miller, A. D.; Růžek, Daniel; Raška, M.; Janeba, Zlatko; Turánek, J.

2016-01-01

Roč. 184, FEB 29 (2016), s. 84-93 ISSN 0378-1135 Institutional support: RVO:60077344 ; RVO:61388963 Keywords : Pseudorabies * Acyclic nucleoside phosphonates * DNA viruses * Cidofovir * Antiviral drugs * DNA polymerase Subject RIV: EE - Microbiology, Virology; CC - Organic Chemistry (UOCHB-X) Impact factor: 2.628, year: 2016

A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification.

Science.gov (United States)

Wen, Cuihong; Zhang, Jing; Rebelo, Ana; Cheng, Fanyong

2016-01-01

Optical Music Recognition (OMR) has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM). The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM), which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs) and Neural Networks (NNs).

The effect of maturation on the configurations of acyclic isoprenoid acids in sediments

Science.gov (United States)

Mackenzie, A. S.; Patience, R. L.; Yon, D. A.; Maxwell, J. R.

1982-05-01

Within a variety of sedimentary rocks of differing maturity, the configurations of a suite of acyclic isoprenoid acids have been examined by gas Chromatographic (in a few cases also by combined gas chromatography-mass spectrometry) analysis of their diastereoisomeric methyl and (-)-menthyl esters. The samples include the Eocene Messel (Germany) and Green River (U.S.) shales, the Permian Irati shale (Brazil) and a number of Lower Toarcian shales from the Paris Basin. The isomer distributions show that isomerisation occurs at the chiral centres with increasing maturation (to increase the number of isomers) and that the rate of isomerisation increases for centres (C-2,C-3) closest to the carboxyl group. These results suggest that adsorption of the carboxyl group to a catalyst surface may control the isomerisation rates by way of access to the catalyst.

The increasing of beta-defensin-2 level in saliva after probiotic Lactobacillus reuteri administration

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Tuti Kusumaningsih

2015-03-01

Full Text Available Background: Commesal bacteria is an excellent inducer for beta defensin-2 (BD-2. Probiotics bacteria Lactobacillus reuteri (L. reuteri as commensal bacteria may play the same role as an excellent inducer for BD-2. Beta defensin is natural antimicrobial peptides widely expressed in oral cavity, including in epithelium salivary gland. Streptococcus mutans (S. mutans as the main of bacteria causing caries are sensitive to BD-2. Purpose: This research was aimed to determine whether administration of probiotic L. reuteri can increase salivary BD-2 level in Wistar rats. Methods: This research can be considered as a laboratory experimental research with a randomized control group post test only design. Twenty-four male Rattus norvegicus Wistar strain rats aged 3 months were used. They were randomly divided into four groups, namely two control groups (negative control group that was not induced and positive control group induced with S. mutans, and two treatment groups (K1: induced with L. reuteri for 14 days and S. mutans for 7 days, and K2: induced with L. reuteri and S. mutans simultaneously for 14 days. L. reuteri culture at a concentration of 108 CFU/ml and S. mutans culture at a concentration of 1010CFU/ml were induced into the oral cavity of Wistar rats. An examination of BD-2 level was then conducted by using Elisa techniques. results: There was significant difference of salivary BD-2 level among those treatment groups (p=0.001. BD-2 level in saliva was increased after the administration of L. reuteri. Conclusion: L. reuteri probiotic can increase salivary BD-2 level in Wistar rats.

Synthesis of New Acadesine (AICA-riboside Analogues Having Acyclic d-Ribityl or 4-Hydroxybutyl Chains in Place of the Ribose

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Gennaro Piccialli

2013-08-01

Full Text Available The antiviral activity of certain acyclic nucleosides drew our attention to the fact that the replacement of the furanose ring by an alkyl group bearing hydroxyl(s could be a useful structural modification to modulate the biological properties of those nucleosides. Herein, we report on the synthesis of some novel acadesine analogues, where the ribose moiety is mimicked by a d-ribityl or by a hydroxybutyl chain.

Novel Antimicrobial Peptides That Inhibit Gram Positive Bacterial Exotoxin Synthesis

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Merriman, Joseph A.; Nemeth, Kimberly A.; Schlievert, Patrick M.

2014-01-01

Gram-positive bacteria, such as Staphylococcus aureus, cause serious human illnesses through combinations of surface virulence factors and secretion of exotoxins. Our prior studies using the protein synthesis inhibitor clindamycin and signal transduction inhibitors glycerol monolaurate and α-globin and β-globin chains of hemoglobin indicate that their abilities to inhibit exotoxin production by S. aureus are separable from abilities to inhibit growth of the organism. Additionally, our previous studies suggest that inhibition of exotoxin production, in absence of ability to kill S. aureus and normal flora lactobacilli, will prevent colonization by pathogenic S. aureus, while not interfering with lactobacilli colonization. These disparate activities may be important in development of novel anti-infective agents that do not alter normal flora. We initiated studies to explore the exotoxin-synthesis-inhibition activity of hemoglobin peptides further to develop potential agents to prevent S. aureus infections. We tested synthesized α-globin chain peptides, synthetic variants of α-globin chain peptides, and two human defensins for ability to inhibit exotoxin production without significantly inhibiting S. aureus growth. All of these peptides were weakly or not inhibitory to bacterial growth. However, the peptides were inhibitory to exotoxin production with increasing activity dependent on increasing numbers of positively-charged amino acids. Additionally, the peptides could be immobilized on agarose beads or have amino acid sequences scrambled and still retain exotoxin-synthesis-inhibition. The peptides are not toxic to human vaginal epithelial cells and do not inhibit growth of normal flora L. crispatus. These peptides may interfere with plasma membrane signal transduction in S. aureus due to their positive charges. PMID:24748386

Regulation of gene expression for defensins and lipid transfer protein in Scots pine seedlings by necrotrophic pathogen Alternaria alternata (Fr.

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Hrunyk Nataliya

2017-06-01

Full Text Available Damping-off disease in pine seedling, caused by fungi and oomycetes (Fusarium, Alternaria, Botrytis, Phytophthora and other species, is one of the most dangerous diseases in conifer nurseries and greenhouses worldwide. Alternaria alternata is a necrotrophic pathogen, which causes early blight in higher plants and results in massive economic losses in agro-industry as well as in forestry. Pine seedlings that lack strong lignificated and suberized cell walls at early stages of their growth are vulnerable to damping-off disease. So, triggering the synthesis of antimicrobial compounds, such as phytoalexins, anticipins and pathogenesis-related (PR proteins, is the main defense strategy to confine pathogens at early stages of pine ontogenesis. Defensins and lipid transfer proteins are members of two PR-protein families (PR-12 and PR-14 respectively and possess antimicrobial activities in vitro through contact toxicity, and the involvement in defense signalling. In this work, we describe the changes in the expression levels of four defensin genes and lipid transfer protein in Scots pine seedlings infected with A. alternata. The expression levels of PsDef1 and PsDef2 increased at 48 h.p.i. (hours post inoculation. The levels of PsDef4 transcripts have increased after 6 and 24 hours. Notably, at 48 h.p.i., the level of PsDef4 transcripts was decreased by 1.2 times compared to control. The level of PsDef3 transcripts was reduced at all three time points. On the other hand, the level of PsLTP1 transcripts increased at 6 h and 48 h.p.i.; while at 24 h.p.i., it decreased by 20% when compared to the control sample. Our results suggest that defensins and lipid transfer protein are involved in the defense response of young Scots pine to necrotrophic pathogen. Thus, those genes can be used as the molecular markers in forestry selection and development of the ecologically friendly remedies for coniferous seedlings cultivation in greenhouses and nurseries.

Optimal allocation of multi-state retransmitters in acyclic transmission networks

International Nuclear Information System (INIS)

Levitin, Gregory

2002-01-01

In this paper, an algorithm for optimal allocation of multi-state elements (MEs) in acyclic transmission networks (ATNs) is suggested. The ATNs consist of a number of positions (nodes) in which MEs capable of receiving and sending a signal are allocated. Each network has a root position where the signal source is located, a number of leaf positions that can only receive a signal, and a number of intermediate positions containing MEs capable of transmitting the received signal to some other nodes. Each ME that is located in a nonleaf node can have different states determined by a set of nodes receiving the signal directly from this ME. The probability of each state is assumed to be known for each ME. The ATN reliability is defined as the probability that a signal from the root node is transmitted to each leaf node. The optimal distribution of MEs with different characteristics among ATN positions provides the greatest possible ATN reliability. The suggested algorithm is based on using a universal generating function technique for network reliability evaluation. A genetic algorithm is used as the optimization tool. Illustrative examples are presented

Identification of sociodemographic and clinical factors associated with the levels of human β-defensin-1 and human β-defensin-2 in the human milk of Han Chinese.

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Wang, Xiao-Fang; Cao, Rui-Ming; Li, Jing; Wu, Jing; Wu, Sheng-Mei; Chen, Tong-Xin

2014-03-14

Human milk provides infants with various immune molecules. The objective of the present study was to measure human β-defensin-1 (hBD-1) and human β-defensin-2 (hBD-2) levels in the colostrum and mature milk of healthy Han Chinese, to identify factors regulating milk hBD-1 and hBD-2 expression and to explore the potential protective effect of milk hBD-1 and hBD-2 on infants. A total of 100 mothers and their babies were recruited into the study. Sociodemographic characteristics and other factors were obtained by a questionnaire. Babies were followed up for a period of 6 months. Colostrum samples (n 100) and mature milk samples (n 82) were collected by hand expression. The hBD-1 and hBD-2 concentrations were measured by ELISA. The hBD-1 and hBD-2 levels differed in the colostrum and mature milk. In the colostrum, the concentration ranges of hBD-1 and hBD-2 were 1·04-12·81 μg/ml and 0·31-19·12 ng/ml, respectively. In mature milk, the hBD-1 and hBD-2 levels were 1·03-31·76 ng/ml and 52·65-182·29 pg/ml, respectively. Several independent factors influence their production. The multivariable analysis showed a strong association between pre-pregnancy BMI and hBD-1 levels in the colostrum (P=0·001), mode of delivery was significantly associated with hBD-2 levels in the colostrum (P=0·006) and gestational age was significantly associated with hBD-1 levels in mature milk (P= 0·010). During the first 6 months of life, the incidence rate of upper respiratory infection was found to be less in the high-colostrum hBD-1 group than in the low-colostrum hBD-1 group (χ²=4·995, P=0·025). The present study suggested that the abundance of hBD-1 in the colostrum may have a protective function against upper respiratory infection for infants younger than 6 months.

A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification.

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Cuihong Wen

Full Text Available Optical Music Recognition (OMR has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM. The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM, which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs and Neural Networks (NNs.

Overexpression of a defensin enhances resistance to a fruit-specific anthracnose fungus in pepper.

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Hyo-Hyoun Seo

Full Text Available Functional characterization of a defensin, J1-1, was conducted to evaluate its biotechnological potentiality in transgenic pepper plants against the causal agent of anthracnose disease, Colletotrichum gloeosporioides. To determine antifungal activity, J1-1 recombinant protein was generated and tested for the activity against C. gloeosporioides, resulting in 50% inhibition of fungal growth at a protein concentration of 0.1 mg·mL-1. To develop transgenic pepper plants resistant to anthracnose disease, J1-1 cDNA under the control of 35S promoter was introduced into pepper via Agrobacterium-mediated genetic transformation method. Southern and Northern blot analyses confirmed that a single copy of the transgene in selected transgenic plants was normally expressed and also stably transmitted to subsequent generations. The insertion of T-DNA was further analyzed in three independent homozygous lines using inverse PCR, and confirmed the integration of transgene in non-coding region of genomic DNA. Immunoblot results showed that the level of J1-1 proteins, which was not normally accumulated in unripe fruits, accumulated high in transgenic plants but appeared to differ among transgenic lines. Moreover, the expression of jasmonic acid-biosynthetic genes and pathogenesis-related genes were up-regulated in the transgenic lines, which is co-related with the resistance of J1-1 transgenic plants to anthracnose disease. Consequently, the constitutive expression of J1-1 in transgenic pepper plants provided strong resistance to the anthracnose fungus that was associated with highly reduced lesion formation and fungal colonization. These results implied the significance of the antifungal protein, J1-1, as a useful agronomic trait to control fungal disease.

Overexpression of a defensin enhances resistance to a fruit-specific anthracnose fungus in pepper.

Science.gov (United States)

Seo, Hyo-Hyoun; Park, Sangkyu; Park, Soomin; Oh, Byung-Jun; Back, Kyoungwhan; Han, Oksoo; Kim, Jeong-Il; Kim, Young Soon

2014-01-01

Functional characterization of a defensin, J1-1, was conducted to evaluate its biotechnological potentiality in transgenic pepper plants against the causal agent of anthracnose disease, Colletotrichum gloeosporioides. To determine antifungal activity, J1-1 recombinant protein was generated and tested for the activity against C. gloeosporioides, resulting in 50% inhibition of fungal growth at a protein concentration of 0.1 mg·mL-1. To develop transgenic pepper plants resistant to anthracnose disease, J1-1 cDNA under the control of 35S promoter was introduced into pepper via Agrobacterium-mediated genetic transformation method. Southern and Northern blot analyses confirmed that a single copy of the transgene in selected transgenic plants was normally expressed and also stably transmitted to subsequent generations. The insertion of T-DNA was further analyzed in three independent homozygous lines using inverse PCR, and confirmed the integration of transgene in non-coding region of genomic DNA. Immunoblot results showed that the level of J1-1 proteins, which was not normally accumulated in unripe fruits, accumulated high in transgenic plants but appeared to differ among transgenic lines. Moreover, the expression of jasmonic acid-biosynthetic genes and pathogenesis-related genes were up-regulated in the transgenic lines, which is co-related with the resistance of J1-1 transgenic plants to anthracnose disease. Consequently, the constitutive expression of J1-1 in transgenic pepper plants provided strong resistance to the anthracnose fungus that was associated with highly reduced lesion formation and fungal colonization. These results implied the significance of the antifungal protein, J1-1, as a useful agronomic trait to control fungal disease.

Human α-defensin (DEFA) gene expression helps to characterise benign and malignant salivary gland tumours

International Nuclear Information System (INIS)

Winter, Jochen; Wenghoefer, Matthias; Pantelis, Annette; Kraus, Dominik; Reckenbeil, Jan; Reich, Rudolf; Jepsen, Soeren; Fischer, Hans-Peter; Allam, Jean-Pierre; Novak, Natalija

2012-01-01

Because of the infrequence of salivary gland tumours and their complex histopathological diagnosis it is still difficult to exactly predict their clinical course by means of recurrence, malignant progression and metastasis. In order to define new proliferation associated genes, purpose of this study was to investigate the expression of human α-defensins (DEFA) 1/3 and 4 in different tumour entities of the salivary glands with respect to malignancy. Tissue of salivary glands (n=10), pleomorphic adenomas (n=10), cystadenolymphomas (n=10), adenocarcinomas (n=10), adenoidcystic carcinomas (n=10), and mucoepidermoid carcinomas (n=10) was obtained during routine surgical procedures. RNA was extracted according to standard protocols. Transcript levels of DEFA 1/3 and 4 were analyzed by quantitative realtime PCR and compared with healthy salivary gland tissue. Additionally, the proteins encoded by DEFA 1/3 and DEFA 4 were visualized in paraffin-embedded tissue sections by immunohistochemical staining. Human α-defensins are traceable in healthy as well as in pathological altered salivary gland tissue. In comparison with healthy tissue, the gene expression of DEFA 1/3 and 4 was significantly (p<0.05) increased in all tumours – except for a significant decrease of DEFA 4 gene expression in pleomorphic adenomas and a similar transcript level for DEFA 1/3 compared to healthy salivary glands. A decreased gene expression of DEFA 1/3 and 4 might protect pleomorphic adenomas from malignant transformation into adenocarcinomas. A similar expression pattern of DEFA-1/3 and -4 in cystadenolymphomas and inflamed salivary glands underlines a potential importance of immunological reactions during the formation of Warthin’s tumour

Expression and new exon mutations of the human Beta defensins and their association on colon cancer development.

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Abdelhabib Semlali

Full Text Available The development of cancer involves genetic predisposition and a variety of environmental exposures. Genome-wide linkage analyses provide evidence for the significant linkage of many diseases to susceptibility loci on chromosome 8p23, the location of the human defensin gene cluster. Human β-defensins (hBDs are important molecules of innate immunity. This study was designed to analyze the expression and genetic variations in hBDs (hBD-1, hBD-2, hBD-3 and hBD-4 and their putative association with colon cancer. hBD gene expression and relative protein expression were evaluated by Real-Time polymerase chain reaction (qPCR and immunohistochemistry, respectively, from 40 normal patients and 40 age-matched patients with colon cancer in Saudi Arabia. In addition, hBD polymorphisms were genotyped by exon sequencing and by promoter methylation. hBD-1, hBD-2, hBD-3 and hBD-4 basal messenger RNA expression was significantly lower in tumor tissues compared with normal tissues. Several insertion mutations were detected in different exons of the analyzed hBDs. However, no methylation in any hBDs promoters was detected because of the limited number of CpG islands in these regions. We demonstrated for the first time a link between hBD expression and colon cancer. This suggests that there is a significant link between innate immunity deregulation through disruption of cationic peptides (hBDs and the potential development of colon cancer.

Salivary human beta defensins affected by oral Candida status in Chinese HIV/AIDS patients undergoing ART.

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Liu, Zhenmin; Yong, Xiangzhi; Jiang, Lanlan; Zhang, Linlin; Lin, Xuefang; Liu, Wei; Peng, Yuanyuan; Tao, Renchuan

2018-03-02

To observe relationships between oral Candida status and salivary human beta defensin-2 and -3 (hBD-2 and hBD-3) levels in HIV/AIDS patients of Guangxi, China during the first year of antiretroviral therapy (ART) dynamically, and to understand the influence of ART on oral Candida status and salivary hBDs expressions. A prospective self-controlled study was carried to observe the dynamic changes of CD4 + T cell counts, oral Candida carriages and salivary hBD-2,3 expressions in HIV/AIDS patients during the first year of ART. A total of 90 HIV/AIDS patients were enrolled, and were examined at the baseline, 3rd, 6th, 12th month of ART. Thirty healthy individuals were enrolled as control. Peripheral blood, oral rinse sample and unstimulated whole saliva were collected to test CD4 + T cell counts, oral Candida carriages and hBD-2,3 expressions. In the first year of ART, CD4 + T cell counts increased significantly. However, oral Candida carriages and oral candidiasis decreased significantly, and salivary hBD-2 expressions in HIV/AIDS patients decreased gradually, salivary hBD-3 levels were highly variable. Salivary hBD-2 concentrations were positively related to oral Candida carriages. The incidence of oral candidiasis among HIV/AIDS patients gradually decreased due to the immune reconstruction of ART. Salivary defensins might play an important role in Candida-host interaction in HIV/AIDS patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Pd-Catalyzed N-Arylation of Secondary Acyclic Amides: Catalyst Development, Scope, and Computational Study

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Hicks, Jacqueline D.; Hyde, Alan M.; Cuezva, Alberto Martinez; Buchwald, Stephen L.

2009-01-01

We report the efficient N-arylation of acyclic secondary amides and related nucleophiles with aryl nonaflates, triflates, and chlorides. This method allows for easy variation of the aromatic component in tertiary aryl amides. A new biaryl phosphine with P-bound 3,5-(bis)trifluoromethylphenyl groups was found to be uniquely effective for this amidation. The critical aspects of the ligand were explored through synthetic, mechanistic, and computational studies. Systematic variation of the ligand revealed the importance of (1) a methoxy group on the aromatic carbon of the “top ring” ortho to the phosphorus and (2) two highly electron-withdrawing P-bound 3,5-(bis)trifluoromethylphenyl groups. Computational studies suggest the electron-deficient nature of the ligand is important in facilitating amide binding to the LPd(II)(Ph)(X) intermediate. PMID:19886610

Multi-Center, Double-Blind, Vehicle-Controlled Clinical Trial of an Alpha and Beta Defensin-Containing Anti-Aging Skin Care Regimen With Clinical, Histopathologic, Immunohistochemical, Photographic, and Ultrasound Evaluation.

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Taub, Amy; Bucay, Vivian; Keller, Gregory; Williams, Jay; Mehregan, Darius

2018-04-01

Anti-aging strategies utilizing stem cells are in the forefront. Alpha and beta defensins are natural immune peptides that have been shown to activate an LGR6-positive stem cell locus in the hair follicle, identified as the source of most new epidermal cells during acute wound healing. We investigated the ability of biomimetic alpha and beta defensin molecules, supplemented with supportive cosmetic ingredients, formulated into three skin care products, at improving the structure and function of aging skin. A participant- and investigator -blinded, placebo-controlled, multi-center trial was performed in outpatient settings. Forty-four healthy female subjects, aged 41-71 years, skin types I-V, completed the study with 2/3 receiving full formula and 1/3 receiving the placebo formula. A skin care regimen of 3 products (serum, cream, and mask) containing alpha-defensin 5 and beta-defensin 3, and other cosmetic ingredients, was applied to the face, post-auricular, and neck skin two times per day for 12 weeks in those receiving full formula, whereas the placebo group received the identically packaged regimen without the active ingredients. Methods of evaluation included histopathology and immunohistochemistry (7 subjects), clinical evaluation of pores, superficial and deep wrinkles based on Griffiths scale, and high-resolution photography (all subjects). In addition, a subset of 15 patients were evaluated with the QuantifiCare system (3-dimensional imaging and skin care scores for evenness, pores, oiliness) and Cortex measurements (high-resolution skin ultrasound, TEWL, elasticity, color, and hydration). Data points for evaluation included baseline, 6 weeks, and 12 weeks. All patients used the same sunscreen and cleanser, which was provided to them. The full formula regimen caused a significantly (P equals 0.027) increased thickness of the epidermis as seen in histology, not seen in the placebo group, with no signs of inflammation. No excessive cell proliferation was

Molecular structure and conformation of two acyclic polythioethers: Implications for the design of heavy metal chelators

Energy Technology Data Exchange (ETDEWEB)

Desper, J.M.; Powell, D.R.; Gellman, S.H. (Univ. of Wisconsin, Madison (USA))

1990-05-23

The crystal structures of the 1,9-bis(p-tolyl)-2,5,8-trithianonane (1) and 1,12-bis(p-tolyl)-2,5,8,11-tetrathiadodecane (2) are reported. Previous studies of macrocyclic polythioethers have revealed a pronounced tendency for backbone CS-CC bonds to adopt gauche torsion angles. The same tendency is observed in the homologous acyclic polythioethers 1 and 2, demonstrating that the gauche preference is not simply the result of a macrocyclic constraint. Because of this gauche preference of CS-CC torsion units and the well-established anti preference of SC-CS torsion units, polythioethers constructed from ethylene sulfide subunits are generally far from preorganized for metal ion chelation.

Polystyrene-Supported Acyclic Diaminocarbene Palladium Complexes in Sonogashira Cross-Coupling: Stability vs. Catalytic Activity

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Vladimir N. Mikhaylov

2018-04-01

Full Text Available Two types of immobilized on the amino-functionalized polystyrene-supported acyclic diaminocarbene palladium complexes (ADC-PdII are investigated under Sonogashira cross-coupling conditions. Depending on substituents in the diaminocarbene fragment immobilized ADC-PdII, systems are found to have different catalytic activity and stability regarding Pd-leaching. PdII-diaminocarbenes possessing protons at both nitrogen atoms smoothly decompose into Pd0-containing species providing a catalytic “cocktail system” with high activity and ability to reuse within nine runs. Polymer-supported palladium (II complex bearing NBn–Ccarbene–NH-moiety exhibits greater stability while noticeably lower activity under Sonogashira cross-coupling. Four molecular ADC-PdII complexes are also synthesized and investigated with the aim of confirming proposed base-promoted pathway of ADC-PdII conversion through carbodiimide into an active Pd0 forms.

A study on β-defensin-2 and histatin-5 as a diagnostic marker of early childhood caries progression

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Anna Jurczak

2015-01-01

Full Text Available BACKGROUND: Recently, a continuous growth of interest has been observed in antimicrobial peptides (AMPs in the light of an alarming increase in resistance of bacteria and fungi against antibiotics. AMPs are used as biomarkers in diagnosis and monitoring of oral cavity pathologies. Therefore, the determination of specific protein profiles in children diagnosed with early childhood caries (ECC might be a basis for effective screening tests and specialized examinations which may enable progression of disease METHODS: The objective of the studies was to determine the role of histatin-5 and β-defensing-2 as a diagnostic marker of early childhood caries progression. In this work, results of concentration determination of two salivary proteins (histatin-5 and β-defensin-2 were presented. In addition, bacterial profiles from dental plaque in various stages of ECC and control were marked. The assessment of alteration in the concentration of these two proteins in a study group of children with various stages of ECC and a control group consisting of children with no symptoms was performed by enzyme-linked immunosorbent assays RESULTS: The statistical analysis showed a significant increase in the concentration of histatin-5 and β-defensin-2 in the study group compared to the control group and correlated with the progression of the disease CONCLUSIONS: The confirmation of concentration changes in these proteins during the progression of dental caries may discover valuable disease progression biomarkers

The Antifungal Plant Defensin HsAFP1 Is a Phosphatidic Acid-Interacting Peptide Inducing Membrane Permeabilization

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Tanne L. Cools

2017-11-01

Full Text Available HsAFP1, a plant defensin isolated from coral bells (Heuchera sanguinea, is characterized by broad-spectrum antifungal activity. Previous studies indicated that HsAFP1 binds to specific fungal membrane components, which had hitherto not been identified, and induces mitochondrial dysfunction and cell membrane permeabilization. In this study, we show that HsAFP1 reversibly interacts with the membrane phospholipid phosphatidic acid (PA, which is a precursor for the biosynthesis of other phospholipids, and to a lesser extent with various phosphatidyl inositol phosphates (PtdInsP’s. Moreover, via reverse ELISA assays we identified two basic amino acids in HsAFP1, namely histidine at position 32 and arginine at position 52, as well as the phosphate group in PA as important features enabling this interaction. Using a HsAFP1 variant, lacking both amino acids (HsAFP1[H32A][R52A], we showed that, as compared to the native peptide, the ability of this variant to bind to PA and PtdInsP’s is reduced (≥74% and the antifungal activity of the variant is reduced (≥2-fold, highlighting the link between PA/PtdInsP binding and antifungal activity. Using fluorescently labelled HsAFP1 in confocal microscopy and flow cytometry assays, we showed that HsAFP1 accumulates at the cell surface of yeast cells with intact membranes, most notably at the buds and septa. The resulting HsAFP1-induced membrane permeabilization is likely to occur after HsAFP1’s internalization. These data provide novel mechanistic insights in the mode of action of the HsAFP1 plant defensin.

Expression of apoplast-targeted plant defensin MtDef4.2 confers resistance to leaf rust pathogen Puccinia triticina but does not affect mycorrhizal symbiosis in transgenic wheat.

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Kaur, Jagdeep; Fellers, John; Adholeya, Alok; Velivelli, Siva L S; El-Mounadi, Kaoutar; Nersesian, Natalya; Clemente, Thomas; Shah, Dilip

2017-02-01

Rust fungi of the order Pucciniales are destructive pathogens of wheat worldwide. Leaf rust caused by the obligate, biotrophic basidiomycete fungus Puccinia triticina (Pt) is an economically important disease capable of causing up to 50 % yield losses. Historically, resistant wheat cultivars have been used to control leaf rust, but genetic resistance is ephemeral and breaks down with the emergence of new virulent Pt races. There is a need to develop alternative measures for control of leaf rust in wheat. Development of transgenic wheat expressing an antifungal defensin offers a promising approach to complement the endogenous resistance genes within the wheat germplasm for durable resistance to Pt. To that end, two different wheat genotypes, Bobwhite and Xin Chun 9 were transformed with a chimeric gene encoding an apoplast-targeted antifungal plant defensin MtDEF4.2 from Medicago truncatula. Transgenic lines from four independent events were further characterized. Homozygous transgenic wheat lines expressing MtDEF4.2 displayed resistance to Pt race MCPSS relative to the non-transgenic controls in growth chamber bioassays. Histopathological analysis suggested the presence of both pre- and posthaustorial resistance to leaf rust in these transgenic lines. MtDEF4.2 did not, however, affect the root colonization of a beneficial arbuscular mycorrhizal fungus Rhizophagus irregularis. This study demonstrates that the expression of apoplast-targeted plant defensin MtDEF4.2 can provide substantial resistance to an economically important leaf rust disease in transgenic wheat without negatively impacting its symbiotic relationship with the beneficial mycorrhizal fungus.

Conformational analysis of an acyclic tetrapeptide: ab-initio structure determination from X-ray powder diffraction, Hirshfeld surface analysis and electronic structure.

Science.gov (United States)

Das, Uday; Naskar, Jishu; Mukherjee, Alok Kumar

2015-12-01

A terminally protected acyclic tetrapeptide has been synthesized, and the crystal structure of its hydrated form, Boc-Tyr-Aib-Tyr-Ile-OMe·2H2O (1), has been determined directly from powder X-ray diffraction data. The backbone conformation of tetrapeptide (1) exhibiting two consecutive β-turns is stabilized by two 4 → 1 intramolecular N-H · · · O hydrogen bonds. In the crystalline state, the tetrapeptide molecules are assembled through water-mediated O-H · · · O hydrogen bonds to form two-dimensional molecular sheets, which are further linked by intermolecular C-H · · · O hydrogen bonds into a three-dimensional supramolecular framework. The molecular electrostatic potential (MEP) surface of (1) has been used to supplement the crystallographic observations. The nature of intermolecular interactions in (1) has been analyzed quantitatively through the Hirshfeld surface and two-dimensional fingerprint plot. The DFT optimized molecular geometry of (1) agrees closely with that obtained from the X-ray structure analysis. The present structure analysis of Boc-Tyr-Aib-Tyr-Ile-OMe·2H2 O (1) represents a case where ab-initio crystal structure of an acyclic tetrapeptide with considerable molecular flexibility has been accomplished from laboratory X-ray powder diffraction data. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

A role for antimicrobial peptides in intestinal microsporidiosis

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Leitch, Gordon J.; Ceballos, Carolina

2009-01-01

SUMMARY Clinical isolates from three microsporidia species, Encephalitozoon intestinalis and Encephalitozoon hellem, and the insect parasite Anncaliia (Brachiola, Nosema) algerae, were used in spore germination and enterocyte-like (C2Bbe1) cell infection assays to determine the effect of a panel of antimicrobial peptides. Spores were incubated with lactoferrin (Lf), lysozyme (Lz), and human beta defensin 2 (HBD2), human alpha defensin 5 (HD5), and human alpha defensin 1 (HNP1), alone and in combination with Lz, prior to germination. Of the Encephalitozoon species only E. hellem spore germination was inhibited by HNP1, while A. algerae spore germination was inhibited by Lf, HBD2, HD5 and HNP1, although HBD2 and HD5 inhibition required the presence of Lz. The effects of HBD2 and HD5 on microsporidia enterocyte infection paralleled their effects on spore germination. Lysozyme alone only inhibited infection with A. algerae, while Lf inhibited infection by E. intestinalis and A. algerae. HNP1 significantly reduced enterocyte infection by all three parasite species and a combination of Lf, Lz and HNP1 caused a further reduced infection with A. algerae. These data suggest that intestinal antimicrobial peptides contribute to the defense of the intestine against infection by luminal microsporidia spores and may partially determine which parasite species infects the intestine. PMID:19079820

Synovial Fluid α-Defensin as a Biomarker for Peri-Prosthetic Joint Infection: A Systematic Review and Meta-Analysis.

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Li, Bin; Chen, Fei; Liu, Yi; Xu, Guokang

Total joint arthroplasty (TJA) has been one of the most beneficial interventions for treating patients suffering from joint disorders. However, peri-prosthetic joint infection (PJI) is a serious complication that often accompanies TJA and the diagnosis of PJI is remains difficult. Questions remain regarding whether certain biomarkers can be valuable in the diagnosis of PJI. We conducted our systematic review by searching PubMed, Embase, Web of Science, the Cochrane Library, and Science Direct with the key words "periprosthetic joint infection," "synovial fluid," and "α-defensin." Studies that provided sufficient data to construct 2 × 2 contingency tables were chosen based on inclusion and exclusion criteria. The quality of included studies was assessed according to the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for the included studies. The summary receiver operating characteristic (SROC) curve and the area under the summary receiver operating characteristic (AUSROC) were used to evaluate the overall diagnostic performance. Eight studies were included in this systematic review. Among them four articles were included in meta-analysis. A total of 421 participants were studied in the meta-analysis. The pooled sensitivity, specificity, and DOR were 0.98 (95% confidence interval [CI]: 0.94-1.00), 0.97 (95% CI: 0.95-0.99), and 1095.49 (95% CI: 283.68.58-4230.45), respectively. The AUSROC was 0.9949 (standard error [SE] 0.0095). Synovial fluid α-defensin is a biomarker of high sensitivity and specificity for the diagnosis of PJI.

Directed acyclic graphs (DAGs): an aid to assess confounding in dental research.

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Merchant, Anwar T; Pitiphat, Waranuch

2002-12-01

Confounding, a special type of bias, occurs when an extraneous factor is associated with the exposure and independently affects the outcome. In order to get an unbiased estimate of the exposure-outcome relationship, we need to identify potential confounders, collect information on them, design appropriate studies, and adjust for confounding in data analysis. However, it is not always clear which variables to collect information on and adjust for in the analyses. Inappropriate adjustment for confounding can even introduce bias where none existed. Directed acyclic graphs (DAGs) provide a method to select potential confounders and minimize bias in the design and analysis of epidemiological studies. DAGs have been used extensively in expert systems and robotics. Robins (1987) introduced the application of DAGs in epidemiology to overcome shortcomings of traditional methods to control for confounding, especially as they related to unmeasured confounding. DAGs provide a quick and visual way to assess confounding without making parametric assumptions. We introduce DAGs, starting with definitions and rules for basic manipulation, stressing more on applications than theory. We then demonstrate their application in the control of confounding through examples of observational and cross-sectional epidemiological studies.

Bifurcatriol, a New Antiprotozoal Acyclic Diterpene from the Brown Alga Bifurcaria bifurcata

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Vangelis Smyrniotopoulos

2017-08-01

Full Text Available Linear diterpenes that are commonly found in brown algae are of high chemotaxonomic and ecological importance. This study reports bifurcatriol (1, a new linear diterpene featuring two stereogenic centers isolated from the Irish brown alga Bifurcaria bifurcata. The gross structure of this new natural product was elucidated based on its spectroscopic data (IR, 1D and 2D-NMR, HRMS. Its absolute configuration was identified by experimental and computational vibrational circular dichroism (VCD spectroscopy, combined with the calculation of 13C-NMR chemical shielding constants. Bifurcatriol (1 was tested for in vitro antiprotozoal activity towards a small panel of parasites (Plasmodium falciparum, Trypanosoma brucei rhodesiense, T. cruzi, and Leishmania donovani and cytotoxicity against mammalian primary cells. The highest activity was exerted against the malaria parasite P. falciparum (IC50 value 0.65 μg/mL with low cytotoxicity (IC50 value 56.6 μg/mL. To our knowledge, this is the first successful application of VCD and DP4 probability analysis of the calculated 13C-NMR chemical shifts for the simultaneous assignment of the absolute configuration of multiple stereogenic centers in a long-chain acyclic natural product.

Synthesis of modified cyclic and acyclic dextrins and comparison of their complexation ability

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Kata Tuza

2014-12-01

Full Text Available We compared the complex forming ability of α-, β- and γ-cyclodextrins (α-CD, β-CD and γ-CD with their open ring analogs. In addition to the native cyclodextrins also modified cyclodextrins and the corresponding maltooligomers, functionalized with neutral 2-hydroxypropyl moieties, were synthesized. A new synthetic route was worked out via bromination, benzylation, deacetylation and debenzylation to obtain the 2-hydroxypropyl maltooligomer counterparts. The complexation properties of non-modified and modified cyclic and acyclic dextrins were studied and compared by photon correlation spectroscopy (PCS and capillary electrophoresis (CE using model guest compounds. In some cases cyclodextrins and their open-ring analogs (acyclodextrins show similar complexation abilities, while with other guests considerably different behavior was observed depending on the molecular dimensions and chemical characteristics of the guests. This was explained by the enhanced flexibility of the non-closed rings. Even the signs of enantiorecognition were observed for the chloropheniramine/hydroxypropyl maltohexaose system. Further studies are planned to help the deeper understanding of the interactions.

Comprehensive assessment of sequence variation within the copy number variable defensin cluster on 8p23 by target enriched in-depth 454 sequencing

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Zhang Xinmin

2011-05-01

Full Text Available Abstract Background In highly copy number variable (CNV regions such as the human defensin gene locus, comprehensive assessment of sequence variations is challenging. PCR approaches are practically restricted to tiny fractions, and next-generation sequencing (NGS approaches of whole individual genomes e.g. by the 1000 Genomes Project is confined by an affordable sequence depth. Combining target enrichment with NGS may represent a feasible approach. Results As a proof of principle, we enriched a ~850 kb section comprising the CNV defensin gene cluster DEFB, the invariable DEFA part and 11 control regions from two genomes by sequence capture and sequenced it by 454 technology. 6,651 differences to the human reference genome were found. Comparison to HapMap genotypes revealed sensitivities and specificities in the range of 94% to 99% for the identification of variations. Using error probabilities for rigorous filtering revealed 2,886 unique single nucleotide variations (SNVs including 358 putative novel ones. DEFB CN determinations by haplotype ratios were in agreement with alternative methods. Conclusion Although currently labor extensive and having high costs, target enriched NGS provides a powerful tool for the comprehensive assessment of SNVs in highly polymorphic CNV regions of individual genomes. Furthermore, it reveals considerable amounts of putative novel variations and simultaneously allows CN estimation.

Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

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Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V.

2012-01-01

A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity

Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

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Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V. [Univ. of Madras, Madras (India)

2012-11-15

A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity.

Saccharomyces boulardii administration can inhibit the formation of gastric lymphoid follicles induced by Helicobacter suis infection.

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Yang, Lin; Tian, Zi-Bin; Yu, Ya-Nan; Zhang, Cui-Ping; Li, Xiao-Yu; Mao, Tao; Jing, Xue; Zhao, Wen-Jun; Ding, Xue-Li; Yang, Ruo-Ming; Zhang, Shuai-Qing

2017-01-01

Helicobacter suis has a greater tendency to induce gastric mucosa-associated lymphoid tissue lymphoma compared with other Helicobacter species in humans and animals. Saccharomyces boulardii has been established as an adjunct to H. pylori eradication treatment, but the effect of S. boulardii administration alone on Helicobacter infection remains unclear. Here, we found that S. boulardii administration effectively decreased the bacterial load of H. suis and inhibited the formation of lymphoid follicles in the stomach post-infection. The levels of H. suis-specific immunoglobulin A (IgA) and secretory IgA in the gastric juice and small intestinal secretions and the production of mouse β-defensin-3 in the small intestinal secretions were significantly increased by S. boulardii administration at 12 weeks after H. suis infection. In addition, feeding with S. boulardii inhibited the expression of inflammatory cytokines and lymphoid follicle formation-related factors after H. suis infection. These results suggested that S. boulardii may be useful for the prevention and treatment of Helicobacter infection-related diseases in humans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Evaluation of Novel Acyclic Nucleoside Phosphonates against Human and Animal Gammaherpesviruses Revealed an Altered Metabolism of Cyclic Prodrugs upon Epstein-Barr Virus Reactivation in P3HR-1 Cells

Czech Academy of Sciences Publication Activity Database

Coen, N.; Duraffour, S.; Naesens, L.; Krečmerová, Marcela; Van Den Oord, J.; Snoeck, R.; Andrei, G.

2013-01-01

Roč. 87, č. 22 (2013), s. 12422-12432 ISSN 0022-538X R&D Projects: GA MPO FR-TI4/625 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonate * gammaherpesvirus * Epstein-Barr virus * Kaposi's sarcoma * HPMP-5-azaC * cidofovir Subject RIV: EE - Microbiology, Virology Impact factor: 4.648, year: 2013

Enhanced inhibition of parvovirus B19 replication by cidofovir in extendedly exposed erythroid progenitor cells.

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Bonvicini, Francesca; Bua, Gloria; Manaresi, Elisabetta; Gallinella, Giorgio

2016-07-15

Human parvovirus B19 (B19V) commonly induces self-limiting infections but can also cause severe clinical manifestations in patients with underlying haematological disorders or with immune system deficits. Currently, therapeutic options for B19V entirely rely on symptomatic and supportive treatments since a specific antiviral therapy is not yet available. Recently a first step in the research for active compounds inhibiting B19V replication has allowed identifying the acyclic nucleoside phosphonate cidofovir (CDV). Herein, the effect of CDV against B19V replication was characterized in human erythroid progenitor cells (EPCs) cultured and infected following different experimental approaches to replicate in vitro the infection of an expanding erythroid cell population in the bone marrow. B19V replication was selectively inhibited both in infected EPCs extendedly exposed to CDV 500μM (viral inhibition 82%) and in serially infected EPCs cultures with passage of the virus progeny, constantly under drug exposure (viral inhibition 99%). In addition, a potent inhibitory effect against B19V (viral inhibition 92%) was assessed in a short-term infection of EPCs treated with CDV 500μM 1day before viral infection. In the evaluated experimental conditions, the enhanced effect of CDV against B19V might be ascribed both to the increased intracellular drug concentration achieved by extended exposure, and to a progressive reduction in efficiency of the replicative process within treated EPCs population. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis and Crystal Structure Determination of a Nickel(II Complex of an Acyclic Pentadentate (N5 Mono Schiff Base Ligand

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R. V. Parish

2001-10-01

Full Text Available The asymmetrical tripodal tetraamine ligand N[(CH23NH2]2[(CH22NH2] (ppe was condensed with 2-acetylpyridine in the presence of nickel(II ion. In ethanolwater solution the reaction stops after the first stage of condensation, and a new nickel(II complex of an acyclic pentadentate (N5 mono Schiff base ligand was obtained. X-ray structure analysis of the resulting complex, [Ni(ppe-py(H2O](ClO42, indicates that condensation with 2-acetylpyridine is at the propylene chain of ppe. The geometry around the nickel ion is distorted octahedral in which the sixth co-ordination group is a solvent molecule.

The effect of acyclic retinoid on the metabolomic profiles of hepatocytes and hepatocellular carcinoma cells.

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Xian-Yang Qin

Full Text Available BACKGROUND/PURPOSE: Acyclic retinoid (ACR is a promising chemopreventive agent for hepatocellular carcinoma (HCC that selectively inhibits the growth of HCC cells (JHH7 but not normal hepatic cells (Hc. To better understand the molecular basis of the selective anti-cancer effect of ACR, we performed nuclear magnetic resonance (NMR-based and capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS-based metabolome analyses in JHH7 and Hc cells after treatment with ACR. METHODOLOGY/PRINCIPAL FINDINGS: NMR-based metabolomics revealed a distinct metabolomic profile of JHH7 cells at 18 h after ACR treatment but not at 4 h after ACR treatment. CE-TOFMS analysis identified 88 principal metabolites in JHH7 and Hc cells after 24 h of treatment with ethanol (EtOH or ACR. The abundance of 71 of these metabolites was significantly different between EtOH-treated control JHH7 and Hc cells, and 49 of these metabolites were significantly down-regulated in the ACR-treated JHH7 cells compared to the EtOH-treated JHH7 cells. Of particular interest, the increase in adenosine-5'-triphosphate (ATP, the main cellular energy source, that was observed in the EtOH-treated control JHH7 cells was almost completely suppressed in the ACR-treated JHH7 cells; treatment with ACR restored ATP to the basal levels observed in both EtOH-control and ACR-treated Hc cells (0.72-fold compared to the EtOH control-treated JHH7 cells. Moreover, real-time PCR analyses revealed that ACR significantly increased the expression of pyruvate dehydrogenase kinases 4 (PDK4, a key regulator of ATP production, in JHH7 cells but not in Hc cells (3.06-fold and 1.20-fold compared to the EtOH control, respectively. CONCLUSIONS/SIGNIFICANCE: The results of the present study suggest that ACR may suppress the enhanced energy metabolism of JHH7 cells but not Hc cells; this occurs at least in part via the cancer-selective enhancement of PDK4 expression. The cancer-selective metabolic pathways

Activity of Genital Tract Secretions and Synthetic Antimicrobial Peptides against Group B Streptococcus.

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Agarwal, Nidhi; Buckley, Niall; Nakra, Natasha; Gialanella, Philip; Yuan, Weirong; Ghartey, Jeny P

2015-12-01

Genital tract secretions inhibit Escherichia coli (E. coli) through antimicrobial peptides (AMP) secreted by the host and vaginal microbiota. However, there are limited data against group B Streptococcus (GBS). Group B Streptococcus were incubated with cervico-vaginal lavage (CVL) samples from healthy non-pregnant women (n = 12) or synthetic AMP and monitored for bacterial growth using a turbidimetric approach. E. coli inhibitory activity was determined by a colony-forming unit assay. None of the CVL samples inhibited GBS. The human neutrophil peptide-1 and human defensin 5 inhibited GBS growth by ≥80% at concentrations ≥20 μg/mL and ≥50 μg/mL, respectively, while human beta-defensin 2 and LL-37 did not inhibit at highest concentration tested (100 μg/mL). In contrast, all AMP inhibited E. coli. Antimicrobial peptides may protect against E. coli colonization but have more limited activity against GBS. Future studies will focus on augmenting host defense with specific AMP to prevent genitourinary infection with these pathogenic organisms. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Expression of avian β-defensins and Toll-like receptor genes in the rooster epididymis during growth and Salmonella infection.

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Anastasiadou, M; Avdi, M; Michailidis, G

2013-08-01

The epididymis is an organ involved in the maturation, transport, and storage of sperm prior to ejaculation. As epididymis is exposed to a constant risk of inflammatory conditions that may lead to transient or permanent sterility, protection of this organ from pathogens is an essential aspect of reproductive physiology. The families of antimicrobial peptides β-defensins and the pattern-recognition receptors Toll-like (TLR) mediate innate immunity in various vertebrates including avian species. As rooster infertility is a major concern in the poultry industry, the objectives of this study were to determine the expression profile of the entire family of the avian β-defensins (AvBD) and TLR genes in the rooster epididymis, to investigate whether sexual maturation affects their epididymidal mRNA abundance and to determine the changes in their expression levels in response to Salmonella enteritidis (SE) infection in the epididymis of sexually mature roosters. RNA was extracted from the epididymis of healthy pubertal, sexually mature and aged birds, and from sexually mature SE infected birds. RT-PCR analysis revealed that 10 members of the AvBD and nine members of the TLR gene families were expressed in the epididymis. Quantitative real-time PCR analysis revealed that the epididymidal mRNA abundance of certain AvBD and TLR genes was developmentally regulated with respect to sexual maturation. SE infection resulted in a significant induction of AvBD 1, 9, 10, 12 and 14, as well as TLR 1-2, 2-1, 2-2, 4, 5 and 7 genes, in the epididymis of sexually mature roosters, compared to healthy birds of the same age. These findings provide strong evidence to suggest that the rooster epididymis is capable of initiating an inflammatory response to Salmonella, through activation of certain members of the AvBD and TLR gene families. Copyright © 2013 Elsevier B.V. All rights reserved.

Transcriptional profiling avian beta-defensins in chicken oviduct epithelial cells before and after infection with Salmonella enterica serovar Enteritidis

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Bailey R Hartford

2009-07-01

Full Text Available Abstract Background Salmonella enterica serovar Enteritidis (SE colonizes the ovary and oviduct of chickens without causing overt clinical signs which can lead to SE-contamination of the content and membrane of shell-eggs as well as hatchery eggs. The organism utilizes the Salmonella Pathogenicity Island-2 encoded type III secretion system (T3SS-2 to promote persistence in the oviduct of laying hens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR was carried out to determine the expression profiles of 14 known avian beta defensins (AvBDs in primary chicken oviduct epithelial cells (COEC before and after infections with a wild type SE strain and T3SS mutant SE strains carrying an inactivated sipA or pipB gene. Results Based on the expression levels in uninfected COEC, AvBDs can be loosely grouped into three categories with AvBD4-5 and AvBD9-12 being constitutively expressed at high levels; AvBD1, AvBD3, and AvBD13-14 at moderate levels; and AvBD2 and AvBD6-8 at minimal levels. Infection with the wild type SE strain temporarily repressed certain highly expressed AvBDs and induced the expression of minimally expressed AvBDs. The pipB mutant, compared to the wild type strain, had reduced suppressive effect on the expression of highly expressed AvBDs. Moreover, the pipB mutant elicited significantly higher levels of the minimally expressed AvBDs than the wild type SE or the sipA mutant did. Conclusion Chicken oviduct epithelial cells express most of the known AvBD genes in response to SE infection. PipB, a T3SS-2 effector protein, plays a role in dampening the β-defensin arm of innate immunity during SE invasion of chicken oviduct epithelium.

Transcriptional profiling avian beta-defensins in chicken oviduct epithelial cells before and after infection with Salmonella enterica serovar Enteritidis.

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Ebers, Katie L; Zhang, C Yan; Zhang, M Zhenyu; Bailey, R Hartford; Zhang, Shuping

2009-07-30

Salmonella enterica serovar Enteritidis (SE) colonizes the ovary and oviduct of chickens without causing overt clinical signs which can lead to SE-contamination of the content and membrane of shell-eggs as well as hatchery eggs. The organism utilizes the Salmonella Pathogenicity Island-2 encoded type III secretion system (T3SS-2) to promote persistence in the oviduct of laying hens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out to determine the expression profiles of 14 known avian beta defensins (AvBDs) in primary chicken oviduct epithelial cells (COEC) before and after infections with a wild type SE strain and T3SS mutant SE strains carrying an inactivated sipA or pipB gene. Based on the expression levels in uninfected COEC, AvBDs can be loosely grouped into three categories with AvBD4-5 and AvBD9-12 being constitutively expressed at high levels; AvBD1, AvBD3, and AvBD13-14 at moderate levels; and AvBD2 and AvBD6-8 at minimal levels. Infection with the wild type SE strain temporarily repressed certain highly expressed AvBDs and induced the expression of minimally expressed AvBDs. The pipB mutant, compared to the wild type strain, had reduced suppressive effect on the expression of highly expressed AvBDs. Moreover, the pipB mutant elicited significantly higher levels of the minimally expressed AvBDs than the wild type SE or the sipA mutant did. Chicken oviduct epithelial cells express most of the known AvBD genes in response to SE infection. PipB, a T3SS-2 effector protein, plays a role in dampening the beta-defensin arm of innate immunity during SE invasion of chicken oviduct epithelium.

A novel 13 residue acyclic peptide from the marine snail, Conus monile, targets potassium channels.

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Sudarslal, Sadasivannair; Singaravadivelan, Govindaswamy; Ramasamy, Palanisamy; Ananda, Kuppanna; Sarma, Siddhartha P; Sikdar, Sujit K; Krishnan, K S; Balaram, Padmanabhan

2004-05-07

A novel 13-residue peptide Mo1659 has been isolated from the venom of a vermivorous cone snail, Conus monile. HPLC fractions of the venom extract yielded an intense UV absorbing fraction with a mass of 1659Da. De novo sequencing using both matrix assisted laser desorption and ionization and electrospray MS/MS methods together with analysis of proteolytic fragments successfully yielded the amino acid sequence, FHGGSWYRFPWGY-NH(2). This was further confirmed by comparison with the chemically synthesized peptide and by conventional Edman sequencing. Mo1659 has an unusual sequence with a preponderance of aromatic residues and the absence of apolar, aliphatic residues like Ala, Val, Leu, and Ile. Mo1659 has no disulfide bridges distinguishing it from the conotoxins and bears no sequence similarity with any of the acyclic peptides isolated thus far from the venom of cone snails. Electrophysiological studies on the effect of Mo1659 on measured currents in dorsal root ganglion neurons suggest that the peptide targets non-inactivating voltage-dependent potassium channels.

Acyclic Diene Metathesis (ADMET Polymerization for Precise Synthesis of Defect-Free Conjugated Polymers with Well-Defined Chain Ends

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Tahmina Haque

2015-03-01

Full Text Available This accounts introduces unique characteristics by adopting the acyclic diene metathesis (ADMET polymerization for synthesis of conjugated polymers, poly(arylene vinylenes, known as promising molecular electronics. The method is more suitable than the other methods in terms of atom efficiency affording defect-free, stereo-regular (exclusive trans polymers with well-defined chain ends; the resultant polymers possess better property than those prepared by the conventional methods. The chain ends (vinyl group in the resultant polymer prepared by ruthenium-carbene catalyst(s can be modified by treating with molybdenum-alkylidene complex (olefin metathesis followed by addition of various aldehyde (Wittig type cleavage, affording the end-functionalized polymers exclusively. An introduction of initiating fragment, the other conjugated segment, and one-pot synthesis of end-functionalized block copolymers, star shape polymers can be achieved by adopting this methodology.

Expression of natural antimicrobial peptide β-defensin-2 and Langerhans cell accumulation in epidermis from human non-healing leg ulcers

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Urszula Wojewodzka

2011-08-01

Full Text Available Chronic wounds like venous calf and diabetic foot ulcers are frequently contaminated and colonized by bacteria and it remains unclear whether there is sufficient expression of defensins and recruitment of epidermal Langerhans cells in the margin of ulcer compared to normal skin. The aim of this study was to examine immunohistochemically the expression of β-defensin-2 (hBD2, GM-CSF, VEGF growth factors and accumulation of CD1a+ Langerhans cells (LC in epidermis from chronic skin ulcers and to compare it to normal skin from the corresponding areas. Studies were carried out in 10 patients with diabetic foot, 10 patients with varicous ulcers of the calf and 10 patients undergoing orthopedic surgery (normal skin for control. Biopsy specimens were immunostained using specific primary antibodies, LSAB+ kit based on biotin-avidinperoxidase complex technique and DAB chromogen. Results were expressed as a mean staining intensity. Statistical analysis of staining showed significantly higher staining of hBD2 in both normal and ulcerated epidermis from foot sole skin compared to calf skin (normal and ulcerated, p<0.05. Chronic ulcers showed the same expression of hBD2 as normal skin. There was significantly lower accumulation of CD1a+ LC in normal epidermis from foot sole skin compared to normal calf skin (p<0.05. Accumulation of CD1a+ LC and GM-CSF upregulation at the border area of diabetic foot ulcer and reduction of LC concentration at the margin of venous calf ulcer compared to normal skin were observed. It seems that normal calf and sole epidermis is, unlike in the mechanisms of innate immunity, influenced by the different keratinocyte turnover and bacterial flora colonizing these regions. Insufficient upregulation of hBD2 in both diabetic foot and venous calf ulcers may suggest the pathological role of this protein in the chronicity of ulcers.

Construction of rat beta defensin-2 eukaryotic expression vector and expression in the transfected rat corneal epithelial cell

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Jing Dan

2017-03-01

Full Text Available AIM: To construct a recombinant eukaryotic expression vector of rat beta defensin-2(rBD-2, transfect it into the rat corneal epithelial cells with lipofection, determine the expression of target gene in the transfected cells, and discuss the potentiality of recombinant plasmid expressed in corneal epithelial cells, hoping to provide an experimental foundation for further study on the antimicrobial activity of rBD-2 in vitro and in vivo and to assess the probability of defensins as a new application for infectious corneal diseases in the future. METHODS: The synthetic rBD-2 DNA fragment was inserted between the XhoI and BamHI restriction enzyme cutting sites of eukaryotic expression vector pIRES2-ZsGreen1 to construct the recombinant plasmid pIRES2-ZsGreen1-rBD-2, then transformed it into E.coli DH5α, positive clones were screened by kanamycin and identified with restriction endonucleases and sequencing analysis. Transfection into the rat corneal epithelial cells was performed by lipofection. Then the experiment was divided into three groups: rat corneal epithelial cell was transfected with the recombinant plasmid pIRES2- ZsGreen1-rBD-2, rat corneal epithelial cell was transfected with the empty plasmid pIRES2-ZsGreen1 and the non-transfected group. The inverted fluorescence microscope was used to observe the transfection process. At last, the level of rBD-2 mRNA expressed in the transfected cells and the control groups are compared by the real-time fluoresence relative quantitative PCR. RESULTS: The recombinant eukaryotic expression vector of pIRES2-ZsGreen1-rBD-2 was successfully constructed. The level of rBD-2 mRNA in transfected cells was significantly higher than that in control groups through the real-time fluorescence relative quantitative PCR. CONCLUSION: The recombinant eukaryotic expression vector pIRES2-ZsGreen1-rBD-2 could be transfected into rat corneal epithelial cells, and exogenous rBD-2 gene could be transcripted into mRNA in

Maximizing survivability of acyclic transmission networks with multi-state retransmitters and vulnerable nodes

International Nuclear Information System (INIS)

Levitin, Gregory

2002-01-01

In this paper, an algorithm for optimal allocation of multi-state elements (MEs) in acyclic transmission networks (ATNs) with vulnerable nodes is suggested. The ATNs consist of a number of positions (nodes) in which MEs capable of receiving and sending a signal are allocated. Each network has a root position where the signal source is located, a number of leaf positions that can only receive a signal, and a number of intermediate positions containing MEs capable of transmitting the received signal to some other nodes. Each ME that is located in a nonleaf node can have different states determined by a set of nodes receiving the signal directly from this ME. The probability of each state is assumed to be known for each ME. Each ATN node with all the MEs allocated at this node can be destroyed by external impact (common cause failure) with a given probability. The ATN survivability is defined as the probability that a signal from the root node is transmitted to each leaf node. The optimal distribution of MEs with different characteristics among ATN positions provides the greatest possible ATN survivability. It is shown that the node vulnerability index affects the optimal distribution. The suggested algorithm is based on using a universal generating function technique for network survivability evaluation. A genetic algorithm is used as the optimization tool. Illustrative examples are presented

Challenging metastatic breast cancer with the natural defensin PvD1.

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Figueira, Tiago N; Oliveira, Filipa D; Almeida, Inês; Mello, Érica O; Gomes, Valdirene M; Castanho, Miguel A R B; Gaspar, Diana

2017-11-09

Metastatic breast cancer is a very serious life threatening condition that poses many challenges for the pharmaceutical development of effective chemotherapeutics. As the therapeutics targeted to the localized masses in breast improve, metastatic lesions in the brain slowly increase in their incidence compromising successful treatment outcomes overall. The blood-brain-barrier (BBB) is one important obstacle for the management of breast cancer brain metastases. New therapeutic approaches are in demand for overcoming the BBB's breaching by breast tumor cells. In this work we demonstrate the potential dual role of a natural antimicrobial plant defensin, PvD 1 : it interferes with the formation of solid tumors in the breast and concomitantly controls adhesion of breast cancer cells to human brain endothelial cells. We have used a combination of techniques that probe PvD 1 's effect at the single cell level and reveal that this peptide can effectively damage breast tumor cells, leaving healthy breast and brain cells unaffected. Results suggest that PvD1 quickly internalizes in cancer cells but remains located in the membrane of normal cells with no significant damage to its structure and biomechanical properties. These interactions in turn modulate cell adhesiveness between tumor and BBB cells. PvD 1 is a potential template for the design of innovative pharmacological approaches for metastatic breast cancer treatment: the manipulation of the biomechanical properties of tumor cells that ultimately prevent their attachment to the BBB.

Effects of Genetically Modified Milk Containing Human Beta-Defensin-3 on Gastrointestinal Health of Mice.

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Xin Chen

Full Text Available This study was performed to investigate the effects of genetically modified (GM milk containing human beta-defensin-3 (HBD3 on mice by a 90-day feeding study. The examined parameters included the digestibility of GM milk, general physical examination, gastric emptying function, intestinal permeability, intestinal microflora composition of mice, and the possibility of horizontal gene transfer (HGT. The emphasis was placed on the effects on gastrointestinal (GI tract due to the fact that GI tract was the first site contacting with food and played crucial roles in metabolic reactions, nutrition absorption and immunity regulation in the host. However, the traditional methods for analyzing the potential toxicological risk of GM product pay little attention on GI health. In this study, the results showed GM milk was easy to be digested in simulated gastric fluid, and it did not have adverse effects on general and GI health compared to conventional milk. And there is little possibility of HGT. This study may enrich the safety assessment of GM product on GI health.

Design and Synthesis of Novel Antimicrobial Acyclic and Heterocyclic Dyes and Their Precursors for Dyeing and/or Textile Finishing Based on 2-N-Acylamino-4,5,6,7-tetrahydro-benzo[b]thiophene Systems

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Rafat Milad Mohareb

2011-07-01

Full Text Available A series of novel polyfunctionalized acyclic and heterocyclic dye precursors and their respective azo (hydrazone counterpart dyes and dye precursors based on conjugate enaminones and/or enaminonitrile moieties were synthesized. The dyes and their precursors are based on 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl-acetamide, 2-ethoxycarbonyl-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl-acetamide or 2-phenylcarbamoyl-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl-acetamide systems as precursors. The latter compounds were used to synthesize polyfunctional thiophene-, thiazole-, pyrazole, pyridine-, pyrimidine-, oxazine-, as well as acyclic moieties. The dyes and dye precursors were characterized by elemental analysis and spectral methods. All dyes and their precursors were screened in vitro and evaluated for both their antibacterial and antifungal activities. MIC data of the novel dye systems and their respective precursors showed significant antimicrobial activity against most tested organisms. Some compounds exhibited comparable or even higher efficiency than selected standards. Dyes were applied at 5% depth for disperse dyeing of nylon, acetate and polyester fabrics. Their spectral characteristics and fastness properties were measured and evaluated.

An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes

Energy Technology Data Exchange (ETDEWEB)

Kiwamoto, R., E-mail: reiko.kiwamoto@wur.nl; Spenkelink, A.; Rietjens, I.M.C.M.; Punt, A.

2015-01-01

Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure–activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment. - Highlights: • Physiologically based in silico models were made for 18 α,β-unsaturated aldehydes. • Kinetic parameters were determined by in vitro incubations and a QSAR approach. • DNA adduct formation was negligible at levels relevant for dietary intake. • The use of QSAR-based PBK/D modelling facilitates group evaluations and read-across.

The Role of α-Defensins 1–3 in Antimicrobial Protection Forming in Children with Recurrent Bronchitis Caused by Bacteria of the Genus Haemophilus

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G.O. Lezhenko

2013-03-01

Full Text Available The level of α-defensins 1–3 (HNP 1–3 has been analyzed in the blood plasma of children with recurrent bronchitis caused by bacteria of the genus Haemophilus. It is shown that the level of HNP 1–3 in the blood plasma depends on the form of Haemophilus. Trigger of HNP 1–3 outflow for neutrophils was the presence of bacterial capsule while presence of L-forms of Haemophilus influenzae wasn’t associated with increase in synthesis of antimicrobial peptides that could be one of the factors of forming of Haemophilus antibiotic resistance.

A dual mechanism involved in membrane and nucleic acid disruption of AvBD103b, a new avian defensin from the king penguin, against Salmonella enteritidis CVCC3377.

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Teng, Da; Wang, Xiumin; Xi, Di; Mao, Ruoyu; Zhang, Yong; Guan, Qingfeng; Zhang, Jun; Wang, Jianhua

2014-10-01

The food-borne bacterial gastrointestinal infection is a serious public health threat. Defensins are evolutionarily conserved innate immune components with broad-spectrum antibacterial activity that do not easily induce resistance. AvBD103b, an avian defensin with potent activity against Salmonella enteritidis, was isolated from the stomach contents of the king penguin (Aptenodytes patagonicus). To elucidate further the antibacterial mechanism of AvBD103b, its effect on the S. enteritidis CVCC3377 cell membrane and intracellular DNA was researched. The cell surface hydrophobicity and a N-phenyl-1-naphthylamine uptake assay demonstrated that AvBD103b treatment increased the cell surface hydrophobicity and outer membrane permeability. Atomic absorption spectrometry, ultraviolet spectrophotometry, flow cytometry, and transmission electron microscopy (TEM) indicated that AvBD103b treatment can lead to the release of the cellular contents and cell death through damage of the membrane. DNA gel retardation and circular dichroism analysis demonstrated that AvBD103b interacted with DNA and intercalated into the DNA base pairs. A cell cycle assay demonstrated that AvBD103b affected cellular functions, such as DNA synthesis. Our results confirmed that AvBD103b exerts its antibacterial activity by damaging the cell membrane and interfering with intracellular DNA, ultimately causing cell death, and suggested that AvBD103b may be a promising candidate as an alternative to antibiotics against S. enteritidis.

Executive Summary of Ares V: Lunar Capabilities Concept Review Through Phase A-Cycle 3

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Holladay, J. B.; Baggett, K. E.; Feldman, S. M.

2011-01-01

This Technical Memorandum (TM) was generated as an overall Ares V summary from the Lunar Capabilities Concept Review (LCCR) through Phase A-Cycle 3 (PA-C3) with the intent that it may be coupled with separately published appendices for a more detailed, integrated narrative. The Ares V has evolved from the initial point of departure (POD) 51.00.48 LCCR configuration to the current candidate POD, PA-C3D, and the family of vehicles concept that contains vehicles PA-C3A through H. The logical progression from concept to POD vehicles is summarized in this TM and captures the trade space and performance of each. The family-of-vehicles concept was assessed during PA-C3 and offered flexibility in the path forward with the ability to add options deemed appropriate. A description of each trade space is given in addition to a summary of each Ares V element. The Ares V contributions to a Mars campaign are also highlighted with the goal of introducing Ares V capabilities within the trade space. The assessment of the Ares V vehicle as it pertains to Mars missions remained locked to the architecture presented in Mars Design Reference Authorization 5.0 using the PA-C3D vehicle configuration to assess Mars transfer vehicle options, in-space EDS capabilities, docking adaptor and propellant transfer assessments, and lunar and Mars synergistic potential.

Acyclic Cucurbit[n]uril-Type Molecular Container Enables Systemic Delivery of Effective Doses of Albendazole for Treatment of SK-OV-3 Xenograft Tumors.

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Hettiarachchi, Gaya; Samanta, Soumen K; Falcinelli, Shane; Zhang, Ben; Moncelet, Damien; Isaacs, Lyle; Briken, Volker

2016-03-07

Approximately, 40-70% of active pharmaceutical ingredients (API) are severely limited by their extremely poor aqueous solubility, and consequently, there is a high demand for excipients that can be used to formulate clinically relevant doses of these drug candidates. Here, proof-of-concept studies demonstrate the potential of our recently discovered acyclic cucurbit[n]uril-type molecular container Motor1 (M1) as a solubilizing agent for insoluble drugs. M1 did not induce significant rates of mutations in various Salmonella typhimurium test strains during the Ames test, suggesting low genotoxicity. M1 also has low risk of causing cardiac toxicity in humans since it did not inhibit the human Ether-à-go-go-Related Gene channel as tested on transfected CHO cell lines via patch clamp analysis. Albendazole (ABZ) is a widely used antihelminthic agent but that has also shown promising efficacy against cancerous cells in vitro. However, due to its low aqueous solubility (2.7 μM) and poor pharmacokinetics, ABZ is clinically limited as an anticancer agent. Here we investigated the potential of M1 as a solubilizing excipient for ABZ formulation. A pharmacokinetic study indicated that ABZ escapes the peritoneal cavity resulting in 78% absolute bioavailability, while its active intermediate metabolite, albendazole sulfoxide, achieved 43% absolute bioavailability. The daily dosing of 681 mg/kg M1 complexed with 3.2 mg/kg of ABZ for 14 days did not result in significant weight loss or pathology in Swiss Webster mice. In vivo efficacy studies using this M1·ABZ inclusion complex showed significant decreases in tumor growth rates and increases in survival of mice bearing SK-OV-3 xenograft tumors. In conclusion, we provide substantial new evidence demonstrating that M1 is a safe and efficient excipient that enables in vivo parenteral delivery of poorly water-soluble APIs.

Urine Levels of Defensin α1 Reflect Kidney Injury in Leptospirosis Patients

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Haorile Chagan-Yasutan

2016-09-01

Full Text Available Leptospirosis is a zoonotic disease whose severe forms are often accompanied by kidney dysfunction. In the present study, urinary markers were studied for potential prediction of disease severity. Urine samples from 135 patients with or without leptospirosis at San Lazaro Hospital, the Philippines, were analyzed. Urine levels of defensin α1 (uDA1 were compared with those of neutrophil gelatinase-associated lipocalin (uNGAL and N-acetyl-β-d-glucosidase (uNAG. Serum creatinine (Cr was used as a marker of kidney injury. The levels of uDA1/Cr, uNGAL/Cr, and uNAG/Cr were positive in 46%, 90%, and 80% of leptospirosis patients, and 69%, 70%, and 70% of non-leptospirosis patients, respectively. In leptospirosis patients, the correlation of uDA1/Cr, uNGAL/Cr and uNAG/Cr levels with serum Cr were r = 0.3 (p < 0.01, r = 0.29 (p < 0.01, and r = 0.02 (p = 0.81, respectively. uDA1/Cr levels were correlated with uNGAL/Cr levels (r = 0.49, p < 0.01 and uNAG/Cr levels (r = 0.47, p < 0.0001 in leptospirosis patients. These findings suggest that uDA1, uNGAL, and uNAG were elevated in leptospirosis patients and reflected various types of kidney damage. uDA1 and uNGAL can be used to track kidney injury in leptospirosis patients because of their correlation with the serum Cr level.

Diesel exhaust particles increase IL-1β-induced human β-defensin expression via NF-κB-mediated pathway in human lung epithelial cells

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Lee Chun

2006-05-01

Full Text Available Abstract Background Human β-defensin (hBD-2, antimicrobial peptide primarily induced in epithelial cells, is a key factor in the innate immune response of the respiratory tract. Several studies showed increased defensin levels in both inflammatory lung diseases, such as cystic fibrosis, diffuse panbronchiolitis, idiopathic pulmonary fibrosis and acute respiratory distress syndrome, and infectious diseases. Recently, epidemiologic studies have demonstrated acute and serious adverse effects of particulate air pollution on respiratory health, especially in people with pre-existing inflammatory lung disease. To elucidate the effect of diesel exhaust particles (DEP on pulmonary innate immune response, we investigated the hBD-2 and interleukin-8 (IL-8 expression to DEP exposure in interleukin-1 beta (IL-1β-stimulated A549 cells. Results IL-1β markedly up-regulated the hBD-2 promoter activity, and the subsequent DEP exposure increased dose-dependently the expression of hBD-2 and inflammatory cytokine IL-8 at the transcriptional level. In addition, DEP further induced the NF-κB activation in IL-1β-stimulated A549 cells more rapidly than in unstimulated control cells, which was showed by nuclear translocation of p65 NF-κB and degradation of IκB-α. The experiment using two NF-κB inhibitors, PDTC and MG132, confirmed that this increase of hBD-2 expression following DEP exposure was regulated through NF-κB-mediated pathway. Conclusion These results demonstrated that DEP exposure increases the expression of antimicrobial peptide and inflammatory cytokine at the transcriptional level in IL-1β-primed A549 epithelial cells and suggested that the increase is mediated at least partially through NF-κB activation. Therefore, DEP exposure may contribute to enhance the airway-responsiveness especially on the patients suffering from chronic respiratory disease.

Expression of human beta-defensins-1-4 in thyroid cancer cells and new insight on biologic activity of hBD-2 in vitro.

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Zhuravel, O V; Gerashchenko, O L; Khetsuriani, M R; Soldatkina, M A; Pogrebnoy, P V

2014-09-01

The study was aimed on analysis of human beta-defensin-1-4 (hBDs) mRNA expression in cultured thyroid cancer cells and evaluation of effects of recombinant hBD-2 (rec-hBD-2) on growth patterns, migration properties and expression of E-cadherin and vimentin in these cells. The study was performed on cultured follicular thyroid cancer WRO cells, papillary thyroid cancer TPC1 cells, and anaplastic thyroid cancer KTC-2 cells. For analysis of hBD-1-4 mRNA expression in thyroid cancer cells, semiquantitative RT-PCR was used. Effects of rec-hBD-2 on cell proliferation, viability, and migration were analyzed using direct cell counting, MTT test, and scratch assay respectively. Expression of vimentin and E-cadherin was evaluated by quantitative PCR (qPCR). By the data of RT-PCR, all three studied thyroid cancer cell lines express hBD-1 and -4 mRNA, but not hBD-2 mRNA, while hBD-3 expression was detected in WRO and KTC-2 cells. The treatment of TPC-1, WRO, and KTC-2 cells with 100-1000 nM rec-hBD-2 resulted in significant concentration-dependent suppression of cell proliferation, viability, and migratory property. By the data of qPCR, significant up-regulation of vimentin expression was registered in KTC-2 and WRO cells treated with 500 nM rec-hBD-2. Significant down-regulation of E-cadherin expression (p cells treated with the defensin. Also, it has been shown that TPC-1 cells treated with 500 nM rec-hBD-2 acquired more elongated morphology. The data demonstrate that hBD-2 in concentrations higher than 100 nM exerts significant concentration-dependent suppression of thyroid cancer cell growth and migration, and affects vimentin and E-cadherin expression dependent on histologic type of thyroid cancer cells.

Acyclic cucurbit[n]uril-type molecular containers: influence of glycoluril oligomer length on their function as solubilizing agents.

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Gilberg, Laura; Zhang, Ben; Zavalij, Peter Y; Sindelar, Vladimir; Isaacs, Lyle

2015-04-07

We present the synthesis of a series of six new glycoluril derived molecular clips and acyclic CB[n]-type molecular containers (1–3) that all feature SO3(−) solubilizing groups but differ in the number of glycoluril rings between the two terminal dialkoxyaromatic sidewalls. We report the X-ray crystal structure of 3b which shows that its dialkoxynaphthalene sidewalls actively define a hydrophobic cavity with high potential to engage in π–π interactions with insoluble aromatic guests. Compounds 1–3 possess very good solubility characteristics (≥38 mM) and undergo only very weak self-association (Ks containers 3a and 3b which feature three glycoluril rings between the terminal dialkoxy-o-xylylene and dialkoxynaphthalene sidewalls are less efficient solubilizing agents than 4a and 4b because of their smaller hydrophobic cavities. Containers 1 and 2 behave as molecular clip type receptors and therefore possess the ability to bind to and thereby solubilize aromatic drugs like camptothecin, ziprasidone, and PBS-1086.

Proteomic Profile of Unstable Atheroma Plaque: Increased Neutrophil Defensin 1, Clusterin, and Apolipoprotein E Levels in Carotid Secretome.

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Aragonès, Gemma; Auguet, Teresa; Guiu-Jurado, Esther; Berlanga, Alba; Curriu, Marta; Martinez, Salomé; Alibalic, Ajla; Aguilar, Carmen; Hernández, Esteban; Camara, María-Luisa; Canela, Núria; Herrero, Pol; Ruyra, Xavier; Martín-Paredero, Vicente; Richart, Cristóbal

2016-03-04

Because of the clinical significance of carotid atherosclerosis, the search for novel biomarkers has become a priority. The aim of the present study was to compare the protein secretion profile of the carotid atherosclerotic plaque (CAP, n = 12) and nonatherosclerotic mammary artery (MA, n = 10) secretomes. We used a nontargeted proteomic approach that incorporated tandem immunoaffinity depletion, iTRAQ labeling, and nanoflow liquid chromatography coupled to high-resolution mass spectrometry. In total, 162 proteins were quantified, of which 25 showed statistically significant differences in secretome levels between carotid atherosclerotic plaque and nondiseased mammary artery. We found increased levels of neutrophil defensin 1, apolipoprotein E, clusterin, and zinc-alpha-2-glycoprotein in CAP secretomes. Results were validated by ELISA assays. Also, differentially secreted proteins are involved in pathways such as focal adhesion and leukocyte transendothelial migration. In conclusion, this study provides a subset of identified proteins that are differently expressed in secretomes of clinical significance.

Expression and purification of moricin CM4 and human β-defensins 4 in Escherichia coli using a new technology.

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Shen, Yang; Ai, Hong-Xin; Song, Ren; Liang, Zhen-Ning; Li, Jian-Feng; Zhang, Shuang-Quan

2010-10-20

Different strategies have been developed to produce small antimicrobial peptides using recombinant techniques. Here we report a new technology of biosynthesis of moricin CM4 and human β-defensins 4 (HβD4) in the Escherichia coli. The CM4 and HβD4 gene were cloned into a vector containing the tags elastin-like peptide (ELP) and intein to construct the expression vector pET-EI-CM4 and pET-EI-HβD4. All the peptides, expressed as soluble fusions, were isolated from the protein debris by the method called inverse transition cycling (ITC) rather than traditional immobilized metal affinity chromatography (IMAC) and separated from the fusion leader by self-cleavage. Fully reduced peptides that were purified exhibited expected antimicrobial activity. The approach described here is a low-cost, convenient and potential way for generating small antimicrobial peptide. Copyright © 2010 Elsevier GmbH. All rights reserved.

The DUB/USP17 deubiquitinating enzymes: A gene family within a tandemly repeated sequence, is also embedded within the copy number variable Beta-defensin cluster

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Scott Christopher J

2010-04-01

Full Text Available Abstract Background The DUB/USP17 subfamily of deubiquitinating enzymes were originally identified as immediate early genes induced in response to cytokine stimulation in mice (DUB-1, DUB-1A, DUB-2, DUB-2A. Subsequently we have identified a number of human family members and shown that one of these (DUB-3 is also cytokine inducible. We originally showed that constitutive expression of DUB-3 can block cell proliferation and more recently we have demonstrated that this is due to its regulation of the ubiquitination and activity of the 'CAAX' box protease RCE1. Results Here we demonstrate that the human DUB/USP17 family members are found on both chromosome 4p16.1, within a block of tandem repeats, and on chromosome 8p23.1, embedded within the copy number variable beta-defensin cluster. In addition, we show that the multiple genes observed in humans and other distantly related mammals have arisen due to the independent expansion of an ancestral sequence within each species. However, it is also apparent when sequences from humans and the more closely related chimpanzee are compared, that duplication events have taken place prior to these species separating. Conclusions The observation that the DUB/USP17 genes, which can influence cell growth and survival, have evolved from an unstable ancestral sequence which has undergone multiple and varied duplications in the species examined marks this as a unique family. In addition, their presence within the beta-defensin repeat raises the question whether they may contribute to the influence of this repeat on immune related conditions.

Identification and primary characterization of a plant antimicrobial ...

African Journals Online (AJOL)

Then an agar-overlay method using fully separated proteins on sodium dodecyl sulphate-polyacryliamide gel electrophoresis (SDS-PAGE) gels was used for initial determination and primary characterization of active putative defensins in the plant seeds. Clear and remarkable zones of inhibition in a region corresponding to ...

Pimecrolimus enhances TLR2/6-induced expression of antimicrobial peptides in keratinocytes.

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Büchau, Amanda S; Schauber, Jürgen; Hultsch, Thomas; Stuetz, Anton; Gallo, Richard L

2008-11-01

Calcineurin inhibitors are potent inhibitors of T-cell-receptor mediated activation of the adaptive immune system. The effects of this class of drug on the innate immune response system are not known. Keratinocytes are essential to innate immunity in skin and rely on toll-like receptors (TLRs) and antimicrobial peptides to appropriately recognize and respond to injury or microbes. In this study we examined the response of cultured human keratinocytes to pimecrolimus. We observed that pimecrolimus enhances distinct expression of cathelicidin, CD14, and human beta-defensin-2 and beta-defensin-3 in response to TLR2/6 ligands. Some of these responses were further enhanced by 1,25 vitamin D3. Pimecrolimus also increased the functional capacity of keratinocytes to inhibit growth of Staphylococcus aureus and decreased TLR2/6-induced expression of IL-10 and IL-1beta. Furthermore, pimecrolimus inhibited nuclear translocation of NFAT and NF-kappaB in keratinocytes. These observations uncover a previously unreported function for pimecrolimus in cutaneous innate host defense.

Crystal structures and inhibition of Trypanosoma brucei hypoxanthine-guanine phosphoribosyltransferase

Czech Academy of Sciences Publication Activity Database

Terán, D.; Hocková, Dana; Česnek, Michal; Zíková, Alena; Naesens, L.; Keough, D. T.; Guddat, L. W.

2016-01-01

Roč. 6, Oct 27 (2016), č. článku 35894. ISSN 2045-2322 R&D Projects: GA ČR(CZ) GA16-06049S; GA MŠk LL1205 Institutional support: RVO:61388963 ; RVO:60077344 Keywords : enzyme inhibitors * acyclic nucleoside phosphonates * HGPRT Subject RIV: CC - Organic Chemistry; EE - Microbiology, Virology (BC-A) Impact factor: 4.259, year: 2016 http://www.nature.com/articles/srep35894

Permeabilization of fungal hyphae by the plant defensin NaD1 occurs through a cell wall-dependent process.

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van der Weerden, Nicole L; Hancock, Robert E W; Anderson, Marilyn A

2010-11-26

The antifungal activity of the plant defensin NaD1 involves specific interaction with the fungal cell wall, followed by permeabilization of the plasma membrane and entry of NaD1 into the cytoplasm. Prior to this study, the role of membrane permeabilization in the activity of NaD1, as well as the relevance of cell wall binding, had not been investigated. To address this, the permeabilization of Fusarium oxysporum f. sp. vasinfectum hyphae by NaD1 was investigated and compared with that by other antimicrobial peptides, including the cecropin-melittin hybrid peptide CP-29, the bovine peptide BMAP-28, and the human peptide LL-37, which are believed to act largely through membrane disruption. NaD1 appeared to permeabilize cells via a novel mechanism that required the presence of the fungal cell wall. NaD1 and Bac2A, a linear variant of the bovine peptide bactenecin, were able to enter the cytoplasm of treated hyphae, indicating that cell death is accelerated by interaction with intracellular targets.

Maize EMBRYO SAC family peptides interact differentially with pollen tubes and fungal cells.

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Woriedh, Mayada; Merkl, Rainer; Dresselhaus, Thomas

2015-08-01

EMBRYO SAC1-4 (ES1-4) peptides belong to the defensin subgroup of cysteine-rich peptides known to mediate pollen tube burst in Zea mays (maize). ES1-4 are reported here to also be capable of inhibiting germination and growth of the maize fungal pathogens Fusarium graminearum and Ustilago maydis at higher concentrations. Dividing the peptides into smaller pieces showed that a 15-amino-acid peptide located in a highly variable loop region lacking similarity to other defensins or defensin-like peptides binds to maize pollen tube surfaces, causing swelling prior to burst. This peptide fragment and a second conserved neighbouring fragment showed suppression of fungal germination and growth. The two peptides caused swelling of fungal cells, production of reactive oxygen species, and finally the formation of big vacuoles prior to burst at high peptide concentration. Furthermore, peptide fragments were found to bind differently to fungal cells. In necrotrophic F. graminearum, a peptide fragment named ES-d bound only at cell surfaces whereas the peptide ES-c bound at cell surfaces and also accumulated inside cells. Conversely, in biotrophic U. maydis, both peptide fragments accumulated inside cells, but, if applied at higher concentration, ES-c but not ES-d accumulated mainly in vacuoles. Mapping of peptide interaction sites identified amino acids differing in pollen tube burst and fungal response reactions. In summary, these findings indicate that residues targeting pollen tube burst in maize are specific to the ES family, while residues targeting fungal growth are conserved within defensins and defensin-like peptides. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Molecular Dynamics Simulations Reveal the Conformational Flexibility of Lipid II and Its Loose Association with the Defensin Plectasin in the Staphylococcus aureus Membrane

DEFF Research Database (Denmark)

Witzke, Sarah; Petersen, Michael; Carpenter, Timothy S.

2016-01-01

dynamics simulation study of the conformational dynamics of Lipid II within a detailed model of the Staphylococcus aureus cell membrane. We show that Lipid II is able to adopt a range of conformations, even within the packed lipidic environment of the membrane. Our simulations also reveal dimerization...... the biosynthesis of the cell wall. Given the urgent need for development of novel antibiotics to counter the growing threat of bacterial infection resistance, it is imperative that a thorough molecular-level characterization of the molecules targeted by antibiotics be achieved. To this end, we present a molecular...... of Lipid II mediated by cations. In the presence of the defensin peptide plectasin, the conformational lability of Lipid II allows it to form loose complexes with the protein, via a number of different binding modes....

Human Alpha Defensin 5 Expression in the Human Kidney and Urinary Tract

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Porter, Edith; Bevins, Charles L.; DiRosario, Julianne; Becknell, Brian; Wang, Huanyu

2012-01-01

Background The mechanisms that maintain sterility in the urinary tract are incompletely understood. Recent studies have implicated the importance of antimicrobial peptides (AMP) in protecting the urinary tract from infection. Here, we characterize the expression and relevance of the AMP human alpha-defensin 5 (HD5) in the human kidney and urinary tract in normal and infected subjects. Methodology/Principal Findings Using RNA isolated from human kidney, ureter, and bladder tissue, we performed quantitative real-time PCR to show that DEFA5, the gene encoding HD5, is constitutively expressed throughout the urinary tract. With pyelonephritis, DEFA5 expression significantly increased in the kidney. Using immunoblot analysis, HD5 production also increased with pyelonephritis. Immunostaining localized HD5 to the urothelium of the bladder and ureter. In the kidney, HD5 was primarily produced in the distal nephron and collecting tubules. Using immunoblot and ELISA assays, HD5 was not routinely detected in non-infected human urine samples while mean urinary HD5 production increased with E.coli urinary tract infection. Conclusions/Significance DEFA5 is expressed throughout the urinary tract in non-infected subjects. Specifically, HD5 is expressed throughout the urothelium of the lower urinary tract and in the collecting tubules of the kidney. With infection, HD5 expression increases in the kidney and levels become detectable in the urine. To our knowledge, our findings represent the first to quantitate HD5 expression and production in the human kidney. Moreover, this is the first report to detect the presence of HD5 in infected urine samples. Our results suggest that HD5 may have an important role in maintaining urinary tract sterility. PMID:22359618

Wavelet entropy and directed acyclic graph support vector machine for detection of patients with unilateral hearing loss in MRI scanning

Directory of Open Access Journals (Sweden)

Shuihua Wang

2016-10-01

Full Text Available (Aim Sensorineural hearing loss (SNHL is correlated to many neurodegenerative disease. Now more and more computer vision based methods are using to detect it in an automatic way. (Materials We have in total 49 subjects, scanned by 3.0T MRI (Siemens Medical Solutions, Erlangen, Germany. The subjects contain 14 patients with right-sided hearing loss (RHL, 15 patients with left-sided hearing loss (LHL, and 20 healthy controls (HC. (Method We treat this as a three-class classification problem: RHL, LHL, and HC. Wavelet entropy (WE was selected from the magnetic resonance images of each subjects, and then submitted to a directed acyclic graph support vector machine (DAG-SVM. (Results The 10 repetition results of 10-fold cross validation shows 3-level decomposition will yield an overall accuracy of 95.10% for this three-class classification problem, higher than feedforward neural network, decision tree, and naive Bayesian classifier. (Conclusions This computer-aided diagnosis system is promising. We hope this study can attract more computer vision method for detecting hearing loss.

The resolution of acyclic P-stereogenic phosphine oxides via the formation of diastereomeric complexes: A case study on ethyl-(2-methylphenyl)-phenylphosphine oxide.

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Bagi, Péter; Varga, Bence; Szilágyi, András; Karaghiosoff, Konstantin; Czugler, Mátyás; Fogassy, Elemér; Keglevich, György

2018-04-01

As an example of acyclic P-chiral phosphine oxides, the resolution of ethyl-(2-methylphenyl)-phenylphosphine oxide was elaborated with TADDOL derivatives, or with calcium salts of the tartaric acid derivatives. Besides the study on the resolving agents, several purification methods were developed in order to prepare enantiopure ethyl-(2-methylphenyl)-phenylphosphine oxide. It was found that the title phosphine oxide is a racemic crystal-forming compound, and the recrystallization of the enantiomeric mixtures could be used for the preparation of pure enantiomers. According to our best method, the (R)-ethyl-(2-methylphenyl)-phenylphosphine oxide could be obtained with an enantiomeric excess of 99% and in a yield of 47%. Complete racemization of the enantiomerically enriched phosphine oxide could be accomplished via the formation of a chlorophosphonium salt. Characterization of the crystal structures of the enantiopure phosphine oxide was complemented with that of the diastereomeric intermediate. X-ray analysis revealed the main nonbonding interactions responsible for enantiomeric recognition. © 2018 Wiley Periodicals, Inc.

Isolation and Characterization of an Acyclic Isoprenoid from Semecarpus anacardium Linn. and its Antibacterial Potential in vitro - Antimicrobial Activity of Semecarpus anacardium Linn. Seeds -

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Ayyakkannu Purushothaman

2017-06-01

Full Text Available Objectives: Semecarpus anacardium Linn. is a plant well-known for its antimicrobial, antidiabetic and anti-arthritic properties in the Ayurvedic and Siddha system of medicine. This has prompted the screening of this plant for antibacterial activity. The main aims of this study were to isolate compounds from the plant’s seeds and to evaluate their antibacterial effects on clinical bacterial test strains. Methods: The n-butanolic concentrate of the seed extract was subjected to thin layer chromatography (TLC and repeated silica gel column chromatography followed by elution with various solvents. The compound was identified based on observed spectral (IR, 1H NMR, 13C NMR and high-resolution mass spectrometry data. The well diffusion method was employed to evaluate the antibacterial activities of the isolated acyclic isoprenoid compound (final concentration: 5 - 15 μg/mL on four test bacterial strains, namely, Staphylococcus aureus (MTCC 96, Bacillus cereus

Oviduct-Specific Expression of Human Neutrophil Defensin 4 in Lentivirally Generated Transgenic Chickens

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Liu, Tongxin; Wu, Hanyu; Cao, Dainan; Li, Qingyuan; Zhang, Yaqiong; Li, Ning; Hu, Xiaoxiang

2015-01-01

The expression of oviduct-specific recombinant proteins in transgenic chickens is a promising technology for the production of therapeutic biologics in eggs. In this study, we constructed a lentiviral vector encoding an expression cassette for human neutrophil defensin 4 (HNP4), a compound that displays high activity against Escherichia coli, and produced transgenic chickens that expressed the recombinant HNP4 protein in egg whites. After the antimicrobial activity of the recombinant HNP4 protein was tested at the cellular level, a 2.8-kb ovalbumin promoter was used to drive HNP4 expression specifically in oviduct tissues. From 669 injected eggs, 218 chickens were successfully hatched. Ten G0 roosters, with semens identified as positive for the transgene, were mated with wild-type hens to generate G1 chickens. From 1,274 total offspring, fifteen G1 transgenic chickens were positive for the transgene, which was confirmed by PCR and Southern blotting. The results of the Southern blotting and genome walking indicated that a single copy of the HNP4 gene was integrated into chromosomes 1, 2, 3, 4, 6 and 24 of the chickens. As expected, HNP4 expression was restricted to the oviduct tissues, and the levels of both transcriptional and translational HNP4 expression varied greatly in transgenic chickens with different transgene insertion sites. The amount of HNP4 protein expressed in the eggs of G1 and G2 heterozygous transgenic chickens ranged from 1.65 μg/ml to 10.18 μg/ml. These results indicated that the production of transgenic chickens that expressed HNP4 protein in egg whites was successful. PMID:26020529

Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model.

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Cervantes-Villagrana, Alberto R; Hernández-Pando, Rogelio; Biragyn, Arya; Castañeda-Delgado, Julio; Bodogai, Monica; Martínez-Fierro, Margarita; Sada, Eduardo; Trujillo, Valentin; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

2013-01-11

The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0-89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Antimicrobial Peptide Human Beta-Defensin-3 Is Induced by Platelet-Released Growth Factors in Primary Keratinocytes

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Andreas Bayer

2017-01-01

Full Text Available Platelet-released growth factors (PRGF and its related clinically used formulations (e.g., Vivostat Platelet-Rich Fibrin (PRF® contain a variety of chemokines, cytokines, and growth factors and are therefore used to support healing of chronic, hard-to-heal, or infected wounds. Human beta-defensin-3 (hBD-3 is an antimicrobial peptide inducibly expressed in human keratinocytes especially upon wounding. The potent antimicrobial activity of hBD-3 together with its wound closure-promoting activities suggests that hBD-3 may play a crucial role in wound healing. Therefore, we analyzed the influence of PRGF on hBD-3 expression in human primary keratinocytes in vitro. In addition, we investigated the influence of Vivostat PRF on hBD-3 expression in artificially generated human skin wounds in vivo. PRGF treatment of primary keratinocytes induced a significant, concentration- and time-dependent increase in hBD-3 gene expression which was partially mediated by the epidermal growth factor receptor (EGFR. In line with these cell culture data, in vivo experiments revealed an enhanced hBD-3 expression in experimentally produced human wounds after the treatment with Vivostat PRF. Thus, the induction of hBD-3 may contribute to the beneficial effects of thrombocyte concentrate lysates in the treatment of chronic or infected wounds.

The Antimicrobial Peptide Human Beta-Defensin-3 Is Induced by Platelet-Released Growth Factors in Primary Keratinocytes

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Lammel, Justus; Tohidnezhad, Mersedeh; Lippross, Sebastian; Behrendt, Peter; Klüter, Tim; Pufe, Thomas; Cremer, Jochen; Jahr, Holger; Rademacher, Franziska; Gläser, Regine; Harder, Jürgen

2017-01-01

Platelet-released growth factors (PRGF) and its related clinically used formulations (e.g., Vivostat Platelet-Rich Fibrin (PRF®)) contain a variety of chemokines, cytokines, and growth factors and are therefore used to support healing of chronic, hard-to-heal, or infected wounds. Human beta-defensin-3 (hBD-3) is an antimicrobial peptide inducibly expressed in human keratinocytes especially upon wounding. The potent antimicrobial activity of hBD-3 together with its wound closure-promoting activities suggests that hBD-3 may play a crucial role in wound healing. Therefore, we analyzed the influence of PRGF on hBD-3 expression in human primary keratinocytes in vitro. In addition, we investigated the influence of Vivostat PRF on hBD-3 expression in artificially generated human skin wounds in vivo. PRGF treatment of primary keratinocytes induced a significant, concentration- and time-dependent increase in hBD-3 gene expression which was partially mediated by the epidermal growth factor receptor (EGFR). In line with these cell culture data, in vivo experiments revealed an enhanced hBD-3 expression in experimentally produced human wounds after the treatment with Vivostat PRF. Thus, the induction of hBD-3 may contribute to the beneficial effects of thrombocyte concentrate lysates in the treatment of chronic or infected wounds. PMID:28811680

Regulatory patterns of a large family of defensin-like genes expressed in nodules of Medicago truncatula.

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Sumitha Nallu

Full Text Available Root nodules are the symbiotic organ of legumes that house nitrogen-fixing bacteria. Many genes are specifically induced in nodules during the interactions between the host plant and symbiotic rhizobia. Information regarding the regulation of expression for most of these genes is lacking. One of the largest gene families expressed in the nodules of the model legume Medicago truncatula is the nodule cysteine-rich (NCR group of defensin-like (DEFL genes. We used a custom Affymetrix microarray to catalog the expression changes of 566 NCRs at different stages of nodule development. Additionally, bacterial mutants were used to understand the importance of the rhizobial partners in induction of NCRs. Expression of early NCRs was detected during the initial infection of rhizobia in nodules and expression continued as nodules became mature. Late NCRs were induced concomitantly with bacteroid development in the nodules. The induction of early and late NCRs was correlated with the number and morphology of rhizobia in the nodule. Conserved 41 to 50 bp motifs identified in the upstream 1,000 bp promoter regions of NCRs were required for promoter activity. These cis-element motifs were found to be unique to the NCR family among all annotated genes in the M. truncatula genome, although they contain sub-regions with clear similarity to known regulatory motifs involved in nodule-specific expression and temporal gene regulation.

Antimicrobial activity of innate immune molecules against Streptococcus pneumoniae, Moraxella catarrhalis and nontypeable Haemophilus influenzae

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Teufert Karen

2004-05-01

lysozyme and β defensin-2 could act synergistically against S. pneumoniae 6B. Moreover, in the liquid broth assay, β defensin-1 showed a modest inhibitory effect on the growth of S. pneumoniae 6B. As assessed by ultrastructural analysis, lysozyme and β defensin-2, and to a much lesser extent, β defensin-1, appeared to be able to cause damage to the bacterial membranes. Conclusions Here we report that lysozyme and the β defensins can inhibit the growth of clinical isolates of otitis media pathogens – namely NTHi strain 12, S. pneumoniae strains 3 and 6B and M. catarrhalis strain 035E – and cause ultrastructural damage to these pathogens. Moreover, we demonstrate that lysozyme and β defensin-2 can act synergistically against S. pneumoniae. These findings are consistent with the concept that secreted antimicrobial peptides and other components of innate immunity constitute the first line of defense protecting host mucosal surfaces, including the tubotympanal (eustachian tube and middle ear cavity mucosa, against pathogens.

Distinct modulation of telomere length in two T-lymphoblastic leukemia cell lines by cytotoxic nucleoside phosphonates PMEG and PMEDAP

Czech Academy of Sciences Publication Activity Database

Hájek, Miroslav; Cvilink, Viktor; Votruba, Ivan; Holý, Antonín; Mertlíková-Kaiserová, Helena

2010-01-01

Roč. 643, č. 1 (2010), s. 6-12 ISSN 0014-2999 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * PMEG * PMEDAP * telomere length * telomerase inhibition Subject RIV: CC - Organic Chemistry Impact factor: 2.737, year: 2010

Synthesis and Characterization of Acyclic and Cyclic Azabridged Ligands Incorporating 2,2'-Bipyridine Subunits and Their Complexes With Copper(II, Cobalt(II, and Nickel(II

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Andrea Pappalardo

2003-07-01

Full Text Available The synthesis of a series of N,N'-disubstituted acyclic (AL and cyclic (CL aza-bridged ligands incorporating 2,2-pipryidine subunits is described. 1H-NMR and IR spectral data support the proposed ligand structures. Dynamic 1H-NMR studies on diurea and diamide derivatives point to the presence of slowly interconverting conformers on the 1H-NMR time-scale, owing to N−H···N hydrogen bonding and/or a restricted rotation around the amide bonds. The ligands synthesized form 1:1 complexes with divalent transition metal ions. Upon complexation, bis-ester derivatives AL5 and CL5 undergo a metal-induced hydrolysis of the ester groups to carboxyl functions, which act as additional binding sites for the metal ion, as well as hydrogen-bonding donor-acceptor binding site to produce dimeric complexes.

Amaranthus caudatus extract inhibits the invasion of E. coli into uroepithelial cells.

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Mohanty, Soumitra; Zambrana, Silvia; Dieulouard, Soizic; Kamolvit, Witchuda; Nilsén, Vera; Gonzales, Eduardo; Östenson, Claes-Göran; Brauner, Annelie

2018-06-28

Amaranthus caudatus is traditionally used to treat infections. Based on its traditional usage, we investigated the effect of A. caudatus on the bladder epithelial cells in the protection of E. coli infection. The direct antimicrobial effects of A. caudatus on uropathogenic bacteria were investigated using minimum inhibitory concentration (MIC) assay. Bladder epithelial cell lines T24 and 5637 and uropathogenic E. coli strain #12 were used to investigate the effect of A. caudatus. Bacterial adhesion and invasion into bladder cells treated with A. caudatus was analyzed. Expression of uroplakin-1a (UPK1A), β1 integrin (ITGB1), caveolin-1 (CAV1) and the antimicrobial peptides human β defensin-2 (DEFB4A) and LL-37 (CAMP) was evaluated using RT-PCR. No direct antibacterial effect on E. coli or any of the tested uropathogenic strains was observed by A. caudatus. However, we demonstrated reduced mRNA expression of uroplakin-1a and caveolin-1, but not β1 integrin after treatment of uroepithelial cells, mirrored by the decreased adhesion and invasion of E. coli. A. caudatus treatment did not induce increased gene expression of the antimicrobial peptides, LL-37 and human β-defensin-2. Our results showed that A. caudatus has a protective role on bladder epithelial cells against uropathogenic E. coli infection by decreasing the bacterial adhesion and invasion, thereby preventing infection. Copyright © 2018 Elsevier B.V. All rights reserved.

Reversible Twisting of Primary Amides via Ground State N-C(O) Destabilization: Highly Twisted Rotationally Inverted Acyclic Amides.

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Meng, Guangrong; Shi, Shicheng; Lalancette, Roger; Szostak, Roman; Szostak, Michal

2018-01-17

Since the seminal studies by Pauling in 1930s, planarity has become the defining characteristic of the amide bond. Planarity of amides has central implications for the reactivity and chemical properties of amides of relevance to a range of chemical disciplines. While the vast majority of amides are planar, nonplanarity has a profound effect on the properties of the amide bond, with the most common method to restrict the amide bond relying on the incorporation of the amide function into a rigid cyclic ring system. In a major departure from this concept, here, we report the first class of acyclic twisted amides that can be prepared, reversibly, from common primary amides in a single, operationally trivial step. Di-tert-butoxycarbonylation of the amide nitrogen atom yields twisted amides in which the amide bond exhibits nearly perpendicular twist. Full structural characterization of a range of electronically diverse compounds from this new class of twisted amides is reported. Through reactivity studies we demonstrate unusual properties of the amide bond, wherein selective cleavage of the amide bond can be achieved by a judicious choice of the reaction conditions. Through computational studies we evaluate structural and energetic details pertaining to the amide bond deformation. The ability to selectively twist common primary amides, in a reversible manner, has important implications for the design and application of the amide bond nonplanarity in structural chemistry, biochemistry and organic synthesis.

Engineered chimeric peptides with antimicrobial and titanium-binding functions to inhibit biofilm formation on Ti implants.

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Geng, Hongjuan; Yuan, Yang; Adayi, Aidina; Zhang, Xu; Song, Xin; Gong, Lei; Zhang, Xi; Gao, Ping

2018-01-01

Titanium (Ti) implants have been commonly used in oral medicine. However, despite their widespread clinical application, these implants are susceptible to failure induced by microbial infection due to bacterial biofilm formation. Immobilization of chimeric peptides with antibacterial properties on the Ti surface may be a promising antimicrobial approach to inhibit biofilm formation. Here, chimeric peptides were designed by connecting three sequences (hBD-3-1/2/3) derived from human β-defensin-3 (hBD-3) with Ti-binding peptide-l (TBP-l: RKLPDAGPMHTW) via a triple glycine (G) linker to modify Ti surfaces. Using X-ray photoelectron spectroscopy (XPS), the properties of individual domains of the chimeric peptides were evaluated for their binding activity toward the Ti surface. The antimicrobial and anti-biofilm efficacy of the peptides against initial settlers, Streptococcus oralis (S. oralis), Streptococcus gordonii (S. gordonii) and Streptococcus sanguinis (S. sanguinis), was evaluated with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Transmission electron microscopy (TEM) and real-time quantitative PCR (qRT-PCR) were used to study cell membrane changes and the underlying antimicrobial mechanism. Compared with the other two peptides, TBP-1-GGG-hBD3-3 presented stronger antibacterial activity and remained stable in saliva and serum. Therefore, it was chosen as the best candidate to modify Ti surfaces in this study. This peptide inhibited the growth of initial streptococci and biofilm formation on Ti surfaces with no cytotoxicity to MC3T3-E1 cells. Disruption of the integrity of bacterial membranes and decreased expression of adhesion protein genes from S. gordonii revealed aspects of the antibacterial mechanism of TBP-1-GGG-hBD3-3. We conclude that engineered chimeric peptides with antimicrobial activity provide a potential solution for inhibiting biofilm formation on Ti surfaces to reduce or prevent the occurrence of peri

Synthetic incorporation of Nile Blue into DNA using 2′-deoxyriboside substitutes: Representative comparison of (R- and (S-aminopropanediol as an acyclic linker

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Daniel Lachmann

2010-02-01

Full Text Available The Nile Blue chromophore was incorporated into oligonucleotides using “click” chemistry for the postsynthetic modification of oligonucleotides. These were synthesized using DNA building block 3 bearing an alkyne group and reacted with the azide 4. (R-3-amino-1,2-propanediol was applied as the linker between the phosphodiester bridges. Two sets of DNA duplexes were prepared. One set carried the chromophore in an A-T environment, the second set in a G-C environment. Both were characterized by optical spectroscopy. Sequence-dependent fluorescence quenching was applied as a sensitive tool to compare the stacking interactions with respect to the chirality of the acyclic linker attachment. The results were compared to recent results from duplexes that carried the Nile Blue label in a sequentially and structurally identical context, except for the opposite chirality of the linker ((S-3-amino-1,2-propandiol. Only minor, negligible differences were observed. Melting temperatures, UV–vis absorption spectra together with fluorescence quenching data indicate that Nile Blue stacks perfectly between the adjacent base pairs regardless of whether it has been attached via an S- or R-configured linker. This result was supported by geometrically optimized DNA models.

Genome-Wide Sensitivity Analysis of the Microsymbiont Sinorhizobium meliloti to Symbiotically Important, Defensin-Like Host Peptides

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Markus F. F. Arnold

2017-08-01

Full Text Available The model legume species Medicago truncatula expresses more than 700 nodule-specific cysteine-rich (NCR signaling peptides that mediate the differentiation of Sinorhizobium meliloti bacteria into nitrogen-fixing bacteroids. NCR peptides are essential for a successful symbiosis in legume plants of the inverted-repeat-lacking clade (IRLC and show similarity to mammalian defensins. In addition to signaling functions, many NCR peptides exhibit antimicrobial activity in vitro and in vivo. Bacterial resistance to these antimicrobial activities is likely to be important for symbiosis. However, the mechanisms used by S. meliloti to resist antimicrobial activity of plant peptides are poorly understood. To address this, we applied a global genetic approach using transposon mutagenesis followed by high-throughput sequencing (Tn-seq to identify S. meliloti genes and pathways that increase or decrease bacterial competitiveness during exposure to the well-studied cationic NCR247 peptide and also to the unrelated model antimicrobial peptide polymyxin B. We identified 78 genes and several diverse pathways whose interruption alters S. meliloti resistance to NCR247. These genes encode the following: (i cell envelope polysaccharide biosynthesis and modification proteins, (ii inner and outer membrane proteins, (iii peptidoglycan (PG effector proteins, and (iv non-membrane-associated factors such as transcriptional regulators and ribosome-associated factors. We describe a previously uncharacterized yet highly conserved peptidase, which protects S. meliloti from NCR247 and increases competitiveness during symbiosis. Additionally, we highlight a considerable number of uncharacterized genes that provide the basis for future studies to investigate the molecular basis of symbiotic development as well as chronic pathogenic interactions.

Diagnosis of prosthetic joint infection with alpha-defensin using a lateral flow device: a multicentre study.

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Berger, P; Van Cauter, M; Driesen, R; Neyt, J; Cornu, O; Bellemans, J

2017-09-01

The purpose of this current multicentre study is to analyse the presence of alpha-defensin proteins in synovial fluid using the Synovasure lateral flow device and to determine its diagnostic reliability and accuracy compared with the prosthetic joint infection (PJI) criteria produced by the Musculoskeletal Infection Society (MSIS). A cohort of 121 patients comprising 85 total knee arthroplasties and 36 total hip arthroplasties was prospectively evaluated between May 2015 and June 2016 in three different orthopaedic centres. The tests were performed on patients with a chronically painful prosthesis undergoing a joint aspiration in a diagnostic pathway or during revision surgery. Based on the MSIS criteria, 34 patients (28%) would have had a PJI, and 87 patients had no PJI. Testing with the lateral flow device had a sensitivity of 97.1% (95% confidence intervals (CI) 84.5 to 99.9) and a specificity of 96.6% (95% CI 90.3 to 99.2). The positive predictive value was 91.7% (95% CI 77.7% to 98.3), and the negative predictive value was 98.8% (95% CI 93.6 to 99.9). Receiver operator characteristics analysis demonstrated an area under the curve for the Synovasure test of 0.97 (95% CI 0.93 to 1.00). Our findings suggest that the Synovasure test has an excellent diagnostic performance to confirm or reject the diagnosis of a PJI. The results are promising for the care of the painful or problematic knee and hip joint arthroplasty and the test should be considered as part of the diagnostic toolbox for PJIs. Cite this article: Bone Joint J 2017;99-B:1176-82. ©2017 The British Editorial Society of Bone & Joint Surgery.

Influence of Th2 Cytokines on the Cornified Envelope, Tight Junction Proteins, and ß-Defensins in Filaggrin-Deficient Skin Equivalents.

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Hönzke, Stefan; Wallmeyer, Leonie; Ostrowski, Anja; Radbruch, Moritz; Mundhenk, Lars; Schäfer-Korting, Monika; Hedtrich, Sarah

2016-03-01

Atopic dermatitis is a chronic skin condition with complex etiology. It is characterized by skin barrier defects and T helper type 2 (Th2)-polarized inflammation. Although mutations in the filaggrin gene are known to be prominent genetic risk factors for the development of atopic dermatitis, the interdependency between these and an altered cytokine milieu is not fully understood. In this study, we evaluated the direct effects of filaggrin deficiency on the cornified envelope, tight junction proteins, and innate immune response, and report the effects of Th2 cytokines in normal and filaggrin-deficient skin equivalents. Supplementation with IL-4 and IL-13 led to distinct histologic changes and significantly increased skin surface pH, both of which were enhanced in filaggrin knockdown skin equivalents. We detected a compensatory up-regulation of involucrin and occludin in filaggrin-deficient skin that was dramatically disturbed when simultaneous inflammation occurred. Furthermore, we found that a lack of filaggrin triggered an up-regulation of human ?-defensin 2 via an unknown mechanism, which was abolished by Th2 cytokine supplementation. Taken together, these results indicate that defects in the epidermal barrier, skin permeability, and cutaneous innate immune response are not primarily linked to filaggrin deficiency but are rather secondarily induced by Th2 inflammation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Generation of transgenic cattle expressing human β-defensin 3 as an approach to reducing susceptibility to Mycobacterium bovis infection.

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Su, Feng; Wang, Yongsheng; Liu, Guanghui; Ru, Kun; Liu, Xin; Yu, Yuan; Liu, Jun; Wu, Yongyan; Quan, Fusheng; Guo, Zekun; Zhang, Yong

2016-03-01

Bovine tuberculosis results from infection with Mycobacterium bovis, a member of the Mycobacterium tuberculosis family. Worldwide, M. bovis infections result in economic losses in the livestock industry; cattle production is especially hard-hit by this disease. Generating M. bovis-resistant cattle may potentially mitigate the impact of this disease by reducing M. bovis infections. In this study, we used transgenic somatic cell nuclear transfer to generate cattle expressing the gene encoding human β-defensin 3 (HBD3), which confers resistance to mycobacteria in vitro. We first generated alveolar epithelial cells expressing HBD3 under the control of the bovine MUC1 promoter, and confirmed that these cells secreted HBD3 and possessed anti-mycobacterial capacity. We then generated and identified transgenic cattle by somatic cell nuclear transfer. The cleavage and blastocyst formation rates of genetically modified embryos provided evidence that monoclonal transgenic bovine fetal fibroblast cells have an integral reprogramming ability that is similar to that of normal cells. Five genetically modified cows were generated, and their anti-mycobacterial capacities were evaluated. Alveolar epithelial cells and macrophages from these cattle expressed higher levels of HBD3 protein compared with non-transgenic cells and possessed effective anti-mycobacterial capacity. These results suggest that the overall risk of M. bovis infection in transgenic cattle is efficiently reduced, and support the development of genetically modified animals as an effective tool to reduce M. bovis infection. © 2016 Federation of European Biochemical Societies.

Evaluation of porcine beta defensins-1 and -2 as antimicrobial peptides for liquid-stored boar semen: Effects on bacterial growth and sperm quality.

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Puig-Timonet, Adrià; Castillo-Martín, Miriam; Pereira, Barbara A; Pinart, Elisabeth; Bonet, Sergi; Yeste, Marc

2018-04-15

The present study evaluated whether two different antimicrobial peptides (AMP): porcine beta defensins-1 (PBD1) and -2 (PBD2) at three concentrations (1.5 μM, 3 μM and 5 μM) could be a suitable alternative to antibiotics in liquid-stored boar semen. Two separate experiments were conducted with liquid-stored boar semen preserved at 17 °C for 9-10 days. In the first one, we evaluated the impact of adding three concentrations of each AMP on the bacterial growth and sperm quality of boar semen stored for 10 days. In the second experiment, the ability of these AMPs to control bacterial growth was determined over a 9-day period, following artificial inoculation with Escherichia coli at 10 7 and 10 8  CFU mL -1 . In both experiments, sperm viability was assessed through flow cytometry, sperm motility was determined with Computer Assisted Sperm Analysis (CASA) and the inhibitory effect on microbial growth was evaluated by bacteria culture on Luria Bertani agar. PBD1 and PBD2 were found to significantly (P extenders for boar semen at a concentration of 3 μM, but do not completely control all bacterial growth. Copyright © 2018 Elsevier Inc. All rights reserved.

Construction of Eukaryotic Expression Vector with mBD1-mBD3 Fusion Genes and Exploring Its Activity against Influenza A Virus

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Wanyi Li

2014-03-01

Full Text Available Influenza (flu pandemics have exhibited a great threat to human health throughout history. With the emergence of drug-resistant strains of influenza A virus (IAV, it is necessary to look for new agents for treatment and transmission prevention of the flu. Defensins are small (2–6 kDa cationic peptides known for their broad-spectrum antimicrobial activity. Beta-defensins (β-defensins are mainly produced by barrier epithelial cells and play an important role in attacking microbe invasion by epithelium. In this study, we focused on the anti-influenza A virus activity of mouse β-defensin 1 (mBD1 and β defensin-3 (mBD3 by synthesizing their fusion peptide with standard recombinant methods. The eukaryotic expression vectors pcDNA3.1(+/mBD1-mBD3 were constructed successfully by overlap-PCR and transfected into Madin-Darby canine kidney (MDCK cells. The MDCK cells transfected by pcDNA3.1(+/mBD1-mBD3 were obtained by G418 screening, and the mBD1-mBD3 stable expression pattern was confirmed in MDCK cells by RT-PCR and immunofluorescence assay. The acquired stable transfected MDCK cells were infected with IAV (A/PR/8/34, H1N1, 0.1 MOI subsequently and the virus titers in cell culture supernatants were analyzed by TCID50 72 h later. The TCID50 titer of the experimental group was clearly lower than that of the control group (p < 0.001. Furthermore, BALB/C mice were injected with liposome-encapsulated pcDNA3.1(+/mBD1-mBD3 through muscle and then challenged with the A/PR/8/34 virus. Results showed the survival rate of 100% and lung index inhibitory rate of 32.6% in pcDNA3.1(+/mBD1-mBD3group; the TCID50 titer of lung homogenates was clearly lower than that of the control group (p < 0.001. This study demonstrates that mBD1-mBD3 expressed by the recombinant plasmid pcDNA3.1(+/mBD1-mBD3 could inhibit influenza A virus replication both in vitro and in vivo. These observations suggested that the recombinant mBD1-mBD3 might be developed into an agent for

Peretinoin, an acyclic retinoid, improves the hepatic gene signature of chronic hepatitis C following curative therapy of hepatocellular carcinoma

International Nuclear Information System (INIS)

Honda, Masao; Yamashita, Taro; Yamashita, Tatsuya; Arai, Kuniaki; Sakai, Yoshio; Sakai, Akito; Nakamura, Mikiko; Mizukoshi, Eishiro; Kaneko, Shuichi

2013-01-01

The acyclic retinoid, peretinoin, has been shown to be effective for suppressing hepatocellular carcinoma (HCC) recurrence after definitive treatment in a small-scale randomized clinical trial. However, little has been documented about the mechanism by which peretinoin exerts its inhibitory effects against recurrent HCC in humans in vivo. Twelve hepatitis C virus-positive patients whose HCC had been eradicated through curative resection or ablation underwent liver biopsy at baseline and week 8 of treatment with either a daily dose of 300 or 600 mg peretinoin. RNA isolated from biopsy samples was subjected to gene expression profile analysis. Peretinoin treatment elevated the expression levels of IGFBP6, RBP1, PRB4, CEBPA, G0S2, TGM2, GPRC5A, CYP26B1, and many other retinoid target genes. Elevated expression was also observed for interferon-, Wnt-, and tumor suppressor-related genes. By contrast, decreased expression levels were found for mTOR- and tumor progression-related genes. Interestingly, gene expression profiles for week 8 of peretinoin treatment could be classified into two groups of recurrence and non-recurrence with a prediction accuracy rate of 79.6% (P<0.05). In the liver of patients with non-recurrence, expression of PDGFC and other angiogenesis genes, cancer stem cell marker genes, and genes related to tumor progression was down-regulated, while expression of genes related to hepatocyte differentiation, tumor suppression genes, and other genes related to apoptosis induction was up-regulated. Gene expression profiling at week 8 of peretinoin treatment could successfully predict HCC recurrence within 2 years. This study is the first to show the effect of peretinoin in suppressing HCC recurrence in vivo based on gene expression profiles and provides a molecular basis for understanding the efficacy of peretinoin

Systemic Induction of the Defensin and Phytoalexin Pisatin Pathways in Pea (Pisum sativum against Aphanomyces euteiches by Acetylated and Nonacetylated Oligogalacturonides

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Sameh Selim

2017-06-01

Full Text Available Oligogalacturonides (OGs are known for their powerful ability to stimulate the plant immune system but little is known about their mode of action in pea (Pisum sativum. In the present study, we investigated the elicitor activity of two fractions of OGs, with polymerization degrees (DPs of 2–25, in pea against Aphanomyces euteiches. One fraction was nonacetylated (OGs − Ac whereas the second one was 30% acetylated (OGs + Ac. OGs were applied by injecting the upper two rachises of the plants at three- and/or four-weeks-old. Five-week-old roots were inoculated with 105 zoospores of A. euteiches. The root infection level was determined at 7, 10 and 14 days after inoculation using the quantitative real-time polymerase chain reaction (qPCR. Results showed significant root infection reductions namely 58, 45 and 48% in the plants treated with 80 µg OGs + Ac and 59, 56 and 65% with 200 µg of OGs − Ac. Gene expression results showed the upregulation of genes involved in the antifungal defensins, lignans and the phytoalexin pisatin pathways and a priming effect in the basal defense, SA and ROS gene markers as a response to OGs. The reduction of the efficient dose in OGs + Ac is suggesting that acetylation is necessary for some specific responses. Our work provides the first evidence for the potential of OGs in the defense induction in pea against Aphanomyces root rot.

Flexible Acyclic Polyol-Chloride Anion Complexes and Their Characterization by Photoelectron Spectroscopy and Variable Temperature Binding Constant Determinations

Energy Technology Data Exchange (ETDEWEB)

Shokri, Alireza; Wang, Xue B.; Wang, Yangping; O' Doherty, George A.; Kass, Steven R.

2016-03-17

Flexible acyclic alcohols with 1–5 hydroxyl groups were bound to chloride anion and these complexes were interrogated by negative ion photoelectron spectroscopy and companion density functional theory computations. The resulting vertical detachment energies are reproduced on average to 0.10 eV by M06-2X/aug-cc-pVTZ predictions and range from 4.45 – 5.96 eV. These values are 0.84 – 2.35 eV larger than the adiabatic detachment energy of Cl– as a result of the larger hydrogen bond networks in the bigger polyols. Adiabatic detachment energies of the alcohol–Cl– clusters are more difficult to determine both experimentally and computationally. This is due to the large geometry changes that occur upon photodetachment and the large bond dissociation energy of H–Cl which enables the resulting chlorine atom to abstract a hydrogen from any of the methylene (CH2) or methine (CH) positions. Both ionic and non-ionic hydrogen bonds (i.e., OH•••Cl– and OH•••OH•••Cl–) form in the larger polyols complexes, and are found to be energetically comparable. Subtle structural differences, consequently can lead to the formation of different types of hydrogen bonds and maximizing the ionic ones is not always preferred. Solution equilibrium binding constants between the alcohols and tetrrabuylammonium chloride (TBACl) in acetonitrile at -24.2, 22.0, and 53.6 °C were also determined. The free energies of association are nearly identical for all of the substrates (i.e., ΔG° = -2.8 ± 0.7 kcal mol–1). Compensating enthalpy and entropy values reveal, contrary to expectation and the intrinsic gas-phase preferences, that the bigger systems with more hydroxyl groups are entropically favored and enthalpically disfavored relative to the smaller species. This suggests that more solvent molecules are released upon binding TBACl to alcohols with more hydroxyl groups and is consistent with the measured negative heat capacities. These quantities increase with

A subchronic feeding safety evaluation of transgenic milk containing human β-defensin 3 on reproductive system of C57BL/6J mouse.

Science.gov (United States)

Gao, Ming-Qing; Zhang, Ruiqi; Yang, Yange; Luo, Yuru; Jiang, Ming; Zhang, Yingli; Zhang, Yong; Qing, Suzhu

2018-05-01

Bovine mastitis is an infectious disease of the mammary gland which has been generally treated by antibiotic delivery. While the increasing drug-resistant bacteria and the high consumption of the antibiotic had become a noticeable concern. In a previous study, a mammary special vector expressing human β-defensin 3 (hBD3) was transfected into bovine fetal fibroblasts to produce mastitis-resistant bovine. This investigation focused on potential unintended effects of transgenic milk containing hBD3 produced by these mastitis-resistant bovine on the reproductive system of C57BL/6J mice. Mice were fed with diets containing transgenic milk or conventional milk, nutritionally balanced to an AIN93G diet for 90 days, and non-milk diet was selected as the negative group. The reproductive system was given special attention including reproductive organ/body ratios, necropsy and histopathology, serum sex hormone, sperm parameters, estrus cycle and the expression level of some specific genes which could indicate the development and function of reproductive system. No diet-related significant differences were observed among three groups in this 90-day feeding study. The results indicated that hBD3 milk does not appear to exert any effect on the reproductive system in C57BL/6J rats compared with conventional milk or the control diet. Copyright © 2018 Elsevier Ltd. All rights reserved.

Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread

Science.gov (United States)

Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

2015-01-01

In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

Maize defensin ZmDEF1 is involved in plant response to fungal ...

African Journals Online (AJOL)

The recombinant ZmDEF1 displays an inhibitive activity against the fungal pathogen, Phytophthora parasitica var. nicotianae. Ectopic expression of the ZmDEF1 gene under the control of the cauliflower mosaic virus (CaMV) 35S promoter conferred enhanced tolerance against P. parasitica in transgenic tobacco plants.

The bacterial defensin resistance protein MprF consists of separable domains for lipid lysinylation and antimicrobial peptide repulsion.

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Christoph M Ernst

2009-11-01

Full Text Available Many bacterial pathogens achieve resistance to defensin-like cationic antimicrobial peptides (CAMPs by the multiple peptide resistance factor (MprF protein. MprF plays a crucial role in Staphylococcus aureus virulence and it is involved in resistance to the CAMP-like antibiotic daptomycin. MprF is a large membrane protein that modifies the anionic phospholipid phosphatidylglycerol with l-lysine, thereby diminishing the bacterial affinity for CAMPs. Its widespread occurrence recommends MprF as a target for novel antimicrobials, although the mode of action of MprF has remained incompletely understood. We demonstrate that the hydrophilic C-terminal domain and six of the fourteen proposed trans-membrane segments of MprF are sufficient for full-level lysyl-phosphatidylglycerol (Lys-PG production and that several conserved amino acid positions in MprF are indispensable for Lys-PG production. Notably, Lys-PG production did not lead to efficient CAMP resistance and most of the Lys-PG remained in the inner leaflet of the cytoplasmic membrane when the large N-terminal hydrophobic domain of MprF was absent, indicating a crucial role of this protein part. The N-terminal domain alone did not confer CAMP resistance or repulsion of the cationic test protein cytochrome c. However, when the N-terminal domain was coexpressed with the Lys-PG synthase domain either in one protein or as two separate proteins, full-level CAMP resistance was achieved. Moreover, only coexpression of the two domains led to efficient Lys-PG translocation to the outer leaflet of the membrane and to full-level cytochrome c repulsion, indicating that the N-terminal domain facilitates the flipping of Lys-PG. Thus, MprF represents a new class of lipid-biosynthetic enzymes with two separable functional domains that synthesize Lys-PG and facilitate Lys-PG translocation. Our study unravels crucial details on the molecular basis of an important bacterial immune evasion mechanism and it may help

Anxiety and retrieval inhibition: support for an enhanced inhibition account.

Science.gov (United States)

Nuñez, Mia; Gregory, Josh; Zinbarg, Richard E

2017-02-01

Retrieval inhibition of negative associations is important for exposure therapy for anxiety, but the relationship between memory inhibition and anxiety is not well understood-anxiety could either be associated with enhanced or deficient inhibition. The present study tested these two competing hypotheses by measuring retrieval inhibition of negative stimuli by related neutral stimuli. Non-clinically anxious undergraduates completed measures of trait and state anxiety and completed a retrieval induced forgetting task. Adaptive forgetting varied with state anxiety. Low levels of state anxiety were associated with no evidence for retrieval inhibition for either threatening or non-threatening categories. Participants in the middle tertile of state anxiety scores exhibited retrieval inhibition for non-threatening categories but not for threatening categories. Participants in the highest tertile of state anxiety, however, exhibited retrieval inhibition for both threatening and non-threatening categories with the magnitude of retrieval inhibition being greater for threatening than non-threatening categories. The data are in line with the avoidance aspect of the vigilance-avoidance theory of anxiety and inhibition. Implications for cognitive behavioural therapy practices are discussed.

Hydrolysate from a mixture of legume flours with antifungal activity as an ingredient for prolonging the shelf-life of wheat bread.

Science.gov (United States)

Rizzello, Carlo Giuseppe; Verni, Michela; Bordignon, Stefano; Gramaglia, Valerio; Gobbetti, Marco

2017-06-01

Aiming at identifying antifungal compounds from plant matrices to be used as ingredients in the bakery industry, a water/salt-soluble extract (WSE) was produced from a legume enzyme hydrolysate, consisting of a mixture of pea, lentil, and faba bean flours, and assayed towards Penicillium roqueforti DPPMAF1. Agar diffusion assays allowed the selection of the optimal processing conditions for hydrolysis. As shown by hyphal radial growth rate, the inhibition was observed towards several fungi, including Aspergillus parasiticus CBS971.97, Penicillium carneum CBS 112297, Penicillium paneum CBS 101032, Penicillium polonicum 112490. A multi-step purification was carried out to identify the active compounds. The antifungal activity was attributed to native proteins (nsLTP, ubiquitin, lectin alpha-1 chain, wound-induced basic protein, defensin-1, defensin-2) and a mixture of peptides, which were released during hydrolysis. Nine peptides were purified and identified as sequences encrypted in legume vicilins, lectins and chitinases. WSE was used as ingredient for making bread under pilot plant conditions. Chemical, structural and sensory characterization of bread showed the lack of significant changes compared to control. The bread made with the legume hydrolysate had a longer shelf-life than that of the control. Copyright © 2016 Elsevier Ltd. All rights reserved.

Defensin-like ZmES4 mediates pollen tube burst in maize via opening of the potassium channel KZM1.

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Suseno Amien

2010-06-01

Full Text Available In contrast to animals and lower plant species, sperm cells of flowering plants are non-motile and are transported to the female gametes via the pollen tube, i.e. the male gametophyte. Upon arrival at the female gametophyte two sperm cells are discharged into the receptive synergid cell to execute double fertilization. The first players involved in inter-gametophyte signaling to attract pollen tubes and to arrest their growth have been recently identified. In contrast the physiological mechanisms leading to pollen tube burst and thus sperm discharge remained elusive. Here, we describe the role of polymorphic defensin-like cysteine-rich proteins ZmES1-4 (Zea mays embryo sac from maize, leading to pollen tube growth arrest, burst, and explosive sperm release. ZmES1-4 genes are exclusively expressed in the cells of the female gametophyte. ZmES4-GFP fusion proteins accumulate in vesicles at the secretory zone of mature synergid cells and are released during the fertilization process. Using RNAi knock-down and synthetic ZmES4 proteins, we found that ZmES4 induces pollen tube burst in a species-preferential manner. Pollen tube plasma membrane depolarization, which occurs immediately after ZmES4 application, as well as channel blocker experiments point to a role of K(+-influx in the pollen tube rupture mechanism. Finally, we discovered the intrinsic rectifying K(+ channel KZM1 as a direct target of ZmES4. Following ZmES4 application, KZM1 opens at physiological membrane potentials and closes after wash-out. In conclusion, we suggest that vesicles containing ZmES4 are released from the synergid cells upon male-female gametophyte signaling. Subsequent interaction between ZmES4 and KZM1 results in channel opening and K(+ influx. We further suggest that K(+ influx leads to water uptake and culminates in osmotic tube burst. The species-preferential activity of polymorphic ZmES4 indicates that the mechanism described represents a pre-zygotic hybridization

Defensin-Like ZmES4 Mediates Pollen Tube Burst in Maize via Opening of the Potassium Channel KZM1

Science.gov (United States)

Márton, Mihaela L.; Debener, Thomas; Geiger, Dietmar; Becker, Dirk; Dresselhaus, Thomas

2010-01-01

In contrast to animals and lower plant species, sperm cells of flowering plants are non-motile and are transported to the female gametes via the pollen tube, i.e. the male gametophyte. Upon arrival at the female gametophyte two sperm cells are discharged into the receptive synergid cell to execute double fertilization. The first players involved in inter-gametophyte signaling to attract pollen tubes and to arrest their growth have been recently identified. In contrast the physiological mechanisms leading to pollen tube burst and thus sperm discharge remained elusive. Here, we describe the role of polymorphic defensin-like cysteine-rich proteins ZmES1-4 (Zea mays embryo sac) from maize, leading to pollen tube growth arrest, burst, and explosive sperm release. ZmES1-4 genes are exclusively expressed in the cells of the female gametophyte. ZmES4-GFP fusion proteins accumulate in vesicles at the secretory zone of mature synergid cells and are released during the fertilization process. Using RNAi knock-down and synthetic ZmES4 proteins, we found that ZmES4 induces pollen tube burst in a species-preferential manner. Pollen tube plasma membrane depolarization, which occurs immediately after ZmES4 application, as well as channel blocker experiments point to a role of K+-influx in the pollen tube rupture mechanism. Finally, we discovered the intrinsic rectifying K+ channel KZM1 as a direct target of ZmES4. Following ZmES4 application, KZM1 opens at physiological membrane potentials and closes after wash-out. In conclusion, we suggest that vesicles containing ZmES4 are released from the synergid cells upon male-female gametophyte signaling. Subsequent interaction between ZmES4 and KZM1 results in channel opening and K+ influx. We further suggest that K+ influx leads to water uptake and culminates in osmotic tube burst. The species-preferential activity of polymorphic ZmES4 indicates that the mechanism described represents a pre-zygotic hybridization barrier and may be a

Avian Antimicrobial Host Defense Peptides: From Biology to Therapeutic Applications

Directory of Open Access Journals (Sweden)

Guolong Zhang

2014-02-01

Full Text Available Host defense peptides (HDPs are an important first line of defense with antimicrobial and immunomoduatory properties. Because they act on the microbial membranes or host immune cells, HDPs pose a low risk of triggering microbial resistance and therefore, are being actively investigated as a novel class of antimicrobials and vaccine adjuvants. Cathelicidins and β-defensins are two major families of HDPs in avian species. More than a dozen HDPs exist in birds, with the genes in each HDP family clustered in a single chromosomal segment, apparently as a result of gene duplication and diversification. In contrast to their mammalian counterparts that adopt various spatial conformations, mature avian cathelicidins are mostly α-helical. Avian β-defensins, on the other hand, adopt triple-stranded β-sheet structures similar to their mammalian relatives. Besides classical β-defensins, a group of avian-specific β-defensin-related peptides, namely ovodefensins, exist with a different six-cysteine motif. Like their mammalian counterparts, avian cathelicidins and defensins are derived from either myeloid or epithelial origin expressed in a majority of tissues with broad-spectrum antibacterial and immune regulatory activities. Structure-function relationship studies with several avian HDPs have led to identification of the peptide analogs with potential for use as antimicrobials and vaccine adjuvants. Dietary modulation of endogenous HDP synthesis has also emerged as a promising alternative approach to disease control and prevention in chickens.

The effect of Bacillus coagulans-fermented and nonfermented Ginkgo biloba on the immunity status of broiler chickens.

Science.gov (United States)

Liu, Xiaoyan; Cao, Guanjun; Wang, Qin; Yao, Xuan; Fang, Binghu

2015-07-01

To evaluate and compare the effects of Bacillus coagulans-fermented Ginkgo biloba (FG) and nonfermented Ginkgo biloba (NFG) on the immunity status of broiler chickens, 180 1-d-old female Arbor Acres chicks were divided into 3 groups and fed either a basal diet, a basal diet supplemented with 0.3% NFG, or a basal diet supplemented with 0.3% FG. Blood samples were taken on the seventh (before vaccination), 14th, 21st, 28th and 35th day for the assessment of serum IL-18 and interferon γ (IFN-γ) levels by ELISA. In addition, Newcastle disease antibody titer analysis was made via hemagglutination and hemagglutination inhibition test methods. On d 35, 6 chickens from each group were sacrificed and the thymus, liver, spleen, small intestine (jejunum segment), cecum, and bursa of Fabricius from each chicken were removed for analysis. RNA was isolated for defensin expression detection by real-time PCR (q-PCR). The results showed that serum IL-18 and IFN-γ levels decreased after treatment with NFG and FG compared with untreated control chickens. The ND antibody titers did not differ significantly between the 3 groups on the seventh, 14th, 21st and 28th day; however, on the 35th day, the ND antibody titers of the NFG and FG chickens were both significantly higher than those of control group chickens. Defensin RNA expression levels were inhibited by NFG; however, they were induced by FG. In conclusion, fermentation of Ginkgo biloba with Bacillus coagulans can promote the beneficial effect of Gingko biloba on the immunity status of broiler chickens.

Human Milk Components Modulate Toll-Like Receptor–Mediated Inflammation12

Science.gov (United States)

He, YingYing; Lawlor, Nathan T

2016-01-01

Toll-like receptor (TLR) signaling is central to innate immunity. Aberrant expression of TLRs is found in neonatal inflammatory diseases. Several bioactive components of human milk modulate TLR expression and signaling pathways, including soluble toll-like receptors (sTLRs), soluble cluster of differentiation (sCD) 14, glycoproteins, small peptides, and oligosaccharides. Some milk components, such as sialyl (α2,3) lactose and lacto-N-fucopentaose III, are reported to increase TLR signaling; under some circumstances this might contribute toward immunologic balance. Human milk on the whole is strongly anti-inflammatory, and contains abundant components that depress TLR signaling pathways: sTLR2 and sCD14 inhibit TLR2 signaling; sCD14, lactadherin, lactoferrin, and 2′-fucosyllactose attenuate TLR4 signaling; 3′-galactosyllactose inhibits TLR3 signaling, and β-defensin 2 inhibits TLR7 signaling. Feeding human milk to neonates decreases their risk of sepsis and necrotizing enterocolitis. Thus, the TLR regulatory components found in human milk hold promise as benign oral prophylactic and therapeutic treatments for the many gastrointestinal inflammatory disorders mediated by abnormal TLR signaling. PMID:26773018

Proactive modulation of long-interval intracortical inhibition during response inhibition

Science.gov (United States)

Cowie, Matthew J.; MacDonald, Hayley J.; Cirillo, John

2016-01-01

Daily activities often require sudden cancellation of preplanned movement, termed response inhibition. When only a subcomponent of a whole response must be suppressed (required here on Partial trials), the ensuing component is markedly delayed. The neural mechanisms underlying partial response inhibition remain unclear. We hypothesized that Partial trials would be associated with nonselective corticomotor suppression and that GABAB receptor-mediated inhibition within primary motor cortex might be responsible for the nonselective corticomotor suppression contributing to Partial trial response delays. Sixteen right-handed participants performed a bimanual anticipatory response inhibition task while single- and paired-pulse transcranial magnetic stimulation was delivered to elicit motor evoked potentials in the left first dorsal interosseous muscle. Lift times, amplitude of motor evoked potentials, and long-interval intracortical inhibition were examined across the different trial types (Go, Stop-Left, Stop-Right, Stop-Both). Go trials produced a tight distribution of lift times around the target, whereas those during Partial trials (Stop-Left and Stop-Right) were substantially delayed. The modulation of motor evoked potential amplitude during Stop-Right trials reflected anticipation, suppression, and subsequent reinitiation of movement. Importantly, suppression was present across all Stop trial types, indicative of a “default” nonselective inhibitory process. Compared with blocks containing only Go trials, inhibition increased when Stop trials were introduced but did not differ between trial types. The amount of inhibition was positively correlated with lift times during Stop-Right trials. Tonic levels of inhibition appear to be proactively modulated by task context and influence the speed at which unimanual responses occur after a nonselective “brake” is applied. PMID:27281744

Antitenascin antibody 81C6 armed with {sup 177}Lu: in vivo comparison of macrocyclic and acyclic ligands

Energy Technology Data Exchange (ETDEWEB)

Yordanov, Alexander T. [Department of Radiology, Duke University Medical Center Durham, NC 27710 (United States); Hens, Marc [Department of Radiology, Duke University Medical Center Durham, NC 27710 (United States); Pegram, Charles [Department of Pathology, Duke University Medical Center Durham, NC 27710 (United States); Bigner, Darell D. [Department of Pathology, Duke University Medical Center Durham, NC 27710 (United States); Zalutsky, Michael R. [Department of Radiology, Duke University Medical Center Durham, NC 27710 (United States)]. E-mail: zalut001@mc.duke.edu

2007-02-15

Introduction: When labeled with iodine-131, the antitenascin monoclonal antibody (mAb) 81C6 has shown promise as a targeted radiotherapeutic in patients with brain tumors. Because of its more favorable {gamma}-ray properties, lutetium-177 might be a better low-energy {beta}-emitter for this type of therapy. Materials and Methods: Chimeric 81C6 (ch81C6) was labeled with {sup 177}Lu using the acyclic 1B4M ligand and the macrocyclic ligands NHS-DOTA and MeO-DOTA and evaluated for binding to tenascin. Three paired-label tissue distribution experiments were performed in normal mice receiving one of the {sup 177}Lu-labeled immunoconjugates plus {sup 125}I-labeled ch81C6 labeled using Iodogen. Paired-label experiments in athymic mice bearing subcutaneous D54 MG human glioma xenografts were done to directly compare the biodistribution of ch81C6-1B4M-{sup 177}Lu and {sup 125}I-labeled ch81C6, and ch81C6-MeO-DOTA-{sup 177}Lu and {sup 125}I-labeled ch81C6. Similar comparisons were done using murine (mu) instead of ch81C6. The primary parameter utilized for evaluation was the {sup 177}Lu/{sup 125}I uptake ratio in each tissue. Results: In the studies performed in normal mice, the NHS-DOTA ligand yielded the highest {sup 177}Lu/{sup 125}I uptake ratios in tissues indicative of loss of label from the chelate; for this reason, only 1B4M and MeO-DOTA were evaluated further. The {sup 177}Lu/{sup 125}I ratio in bone increased gradually with time for the chimeric conjugates; however, there were no significant differences between ch81C6-1B4M-DTPA-{sup 177}Lu and ch81C6-MeO-DOTA-{sup 177}Lu. In contrast, mu81C6-1B4M-DTPA-{sup 177}Lu and mu81C6-MeO-DOTA-{sup 177}Lu showed a more dramatic increase in the {sup 177}Lu/{sup 125}I ratio in bone - from 2.4{+-}0.3 and 1.7{+-}0.2 at Day 1 to 8.5{+-}1.1 and 4.2{+-}0.5 at Day 7, respectively. Conclusion: With these antitenascin constructs, the nature of the mAb had a profound influence on the relative degree of loss of {sup 177}Lu from these

Periodontopathogens and human β-defensin-2 expression in gingival crevicular fluid from patients with periodontal disease in Guangxi, China.

Science.gov (United States)

Yong, X; Chen, Y; Tao, R; Zeng, Q; Liu, Z; Jiang, L; Ye, L; Lin, X

2015-06-01

Periodontal diseases are often induced by periodontopathogens, which are always exposed to certain innate immune factors in gingival crevicular fluid, including human β-defensin-2 (hBD-2). This study aims to investigate the relationship among periodontopathogens, clinical parameters and hBD-2 expression. Thirty-two healthy controls, 42 patients with chronic gingivitis and 95 patients with chronic periodontitis were recruited in Guangxi, China. Bleeding index, probing depth and clinical attachment level were measured for all teeth including mesiobuccal, buccal, disobuccal, mesiolingual, lingual, disolingual six sites of all patient. Gingival crevicular fluid samples were collected from the study sites. The prevalence and copy numbers (CN) of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, Tannerella forsythia and total bacteria in gingival crevicular fluid were quantified by real-time PCR. The hBD-2 concentration in gingival crevicular fluid was measured by ELISA. Both the prevalence and the CN of A. actinomycetemcomitans, P. gingivalis, T. denticola and T. forsythia were higher in patients with chronic periodontitis than in healthy controls and patients with chronic gingivitis; however, there was no significant difference in the prevalence of P. intermedia among the three study groups, and the highest CN was found in patients with chronic gingivitis, rather than in patients with chronic periodontitis. The loads of P. gingivalis, P. intermedia, T. denticola and total bacteria were positively related to probing depth, bleeding index and clinical attachment level. The concentration of hBD-2 in gingival crevicular fluid was higher in patients with chronic gingivitis and in patients with chronic periodontitis than in healthy controls. In addition, the hBD-2 concentration was positively related to the CN of P. gingivalis, T. forsythia and total bacteria, as well as to bleeding index and probing depth. The

Probabilistic Networks

DEFF Research Database (Denmark)

Jensen, Finn Verner; Lauritzen, Steffen Lilholt

2001-01-01

This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs.......This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs....

Sulfur-inhibited Thermosphaera aggregans sp. nov., a new genus of hyperthermophilic archaea isolated after its prediction from environmentally derived 16S rRNA sequences.

Science.gov (United States)

Huber, R; Dyba, D; Huber, H; Burggraf, S; Rachel, R

1998-01-01

Recently, a new procedure was developed which allowed for the first time the isolation of a hyperthermophilic archaeum tracked by 165 rRNA analysis from a terrestrial hot solfataric spring ('Obsidian Pool', Yellowstone National Park, WY, USA). This novel isolate is characterized here. Cells are round cocci with a diameter of 0.2-0.8 micron, occurring singly, in pairs, short chains and in grape-like aggregates. The aggregates exhibit a weak bluish-green fluorescence under UV radiation at 420 nm. The new isolate is an anaerobic obligate heterotroph, using preferentially yeast extract for growth. The metabolic products include CO2, H2, acetate and isovalerate. Growth is observed between 65 and 90 degrees C (optimum: 85 degrees C), from pH 5.0 to 7.0 (optimum: 6.5) and up to 0.7% NaCl. The apparent activation energy for growth is about 149 kJ mol-1. Elemental sulfur or hydrogen inhibits growth. The core lipids consist mainly of acyclic and cyclic glycerol diphytanyl tetraethers. The cell envelope contains a cytoplasmic membrane covered by an amorphous layer of unknown composition; there is no evidence for a regularly arrayed surface-layer protein. The G + C content is 46 mol%. On the basis of 165 rRNA sequence comparisons in combination with morphological, physiological and biochemical properties, the isolate represents a new genus within the Desulfurococcaceae, which has been named Thermosphaera. The type species is Thermosphaera aggregans, the type strain is isolate M11TLT (= DSM 11486T).

The Toll-like receptor 1/2 agonists Pam(3) CSK(4) and human β-defensin-3 differentially induce interleukin-10 and nuclear factor-κB signalling patterns in human monocytes.

Science.gov (United States)

Funderburg, Nicholas T; Jadlowsky, Julie K; Lederman, Michael M; Feng, Zhimin; Weinberg, Aaron; Sieg, Scott F

2011-10-01

Human β-defensin 3 (hBD-3) activates antigen-presenting cells through Toll-like receptors (TLRs) 1/2. Several TLR1/2 agonists have been identified but little is known about how they might differentially affect cellular activation. We compared the effects of hBD-3 with those of another TLR1/2 agonist, Pam(3) CSK(4) , in human monocytes. Monocytes incubated with hBD-3 or Pam(3) CSK(4) produced interleukin-6 (IL-6), IL-8 and IL-1β, but only Pam(3) CSK(4) induced IL-10. The IL-10 induction by Pam(3) CSK(4) caused down-modulation of the co-stimulatory molecule, CD86, whereas CD86 expression was increased in monocytes exposed to hBD-3. Assessment of signalling pathways linked to IL-10 induction indicated that mitogen-activated protein kinases were activated similarly by hBD-3 or Pam(3) CSK(4) , whereas the non-canonical nuclear factor-κB pathway was only induced by Pam(3) CSK(4) . Our data suggest that the lack of non-canonical nuclear factor-κB signalling by hBD-3 could contribute to the failure of this TLR agonist to induce production of the anti-inflammatory cytokine, IL-10, in human monocytes. © 2011 The Authors. Immunology © 2011 Blackwell Publishing Ltd.

INHIBITION IN SPEAKING PERFORMANCE

OpenAIRE

Humaera, Isna

2015-01-01

The most common problem encountered by the learner in the languageacquisition process is learner inhibition. Inhibition refers to a temperamentaltendency to display wariness, fearfulness, or restrain in response tounfamiliar people, objects, and situations. There are some factors that causeinhibition, such as lack of motivation, shyness, self-confidence, self-esteem,and language ego. There are also levels of inhibition, it refers to kinds ofinhibition and caused of inhibition itself. Teacher ...

Saturated versus unsaturated hydrocarbon interactions with carbon nanostructures

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Deivasigamani eUmadevi

2014-09-01

Full Text Available The interactions of various acyclic and cyclic hydrocarbons in both saturated and unsaturated forms with the carbon nanostructures (CNSs have been explored by using density functional theory (DFT calculations. Model systems representing armchair and zigzag carbon nanotubes (CNTs and graphene have been considered to investigate the effect of chirality and curvature of the CNSs towards these interactions. Results of this study reveal contrasting binding nature of the acyclic and cyclic hydrocarbons towards CNSs. While the saturated molecules show stronger binding affinity in acyclic hydrocarbons; the unsaturated molecules exhibit higher binding affinity in cyclic hydrocarbons. In addition, acyclic hydrocarbons exhibit stronger binding affinity towards the CNSs when compared to their corresponding cyclic counterparts. The computed results excellently corroborate the experimental observations. The interaction of hydrocarbons with graphene is more favourable when compared with CNTs. Bader’s theory of atoms in molecules has been invoked to characterize the noncovalent interactions of saturated and unsaturated hydrocarbons. Our results are expected to provide useful insights towards the development of rational strategies for designing complexes with desired noncovalent interaction involving CNSs.

A Combinatorial Formula for Certain Elements of Upper Cluster Algebras

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Lee, Kyungyong; Li, Li; Mills, Matthew R.

2015-06-01

We develop an elementary formula for certain non-trivial elements of upper cluster algebras. These elements have positive coefficients. We show that when the cluster algebra is acyclic these elements form a basis. Using this formula, we show that each non-acyclic skew-symmetric cluster algebra of rank 3 is properly contained in its upper cluster algebra.

Inhibition of lactation.

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Llewellyn-Jones, D

1975-01-01

The mechanism and hormonal regulation of lactation is explained and illustrated with a schematic representation. Circulating estrogen above a critical amount seems to be the inhibitory factor controlling lactation during pregnancy. Once delivery occurs, the level of estrogen falls, that of prolactin rises, and lactation begins. Nonsuckling can be used to inhibit lactation. Estrogens can also be used to inhibit lactation more quickly and with less pain. The reported association between estrogens and puerperal thromboembolism cannot be considered conclusive due to defects in the reporting studies. There is no reason not to use estrogens in lactation inhibition except for women over 35 who experienced a surgical delivery. Alternative therapy is available for these women. The recently-developed drug, brom-ergocryptine, may replace other methods of lactation inhibition.

CCL20 and Beta-Defensin 2 Production by Human Lung Epithelial Cells and Macrophages in Response to Brucella abortus Infection

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Fernández, Andrea G.; Bonetto, Josefina; Giambartolomei, Guillermo H.; Fossati, Carlos A.; Baldi, Pablo C.

2015-01-01

Both CCL20 and human β-defensin 2 (hBD2) interact with the same membrane receptor and display chemotactic and antimicrobial activities. They are produced by airway epithelia in response to infectious agents and proinflammatory cytokines. Whereas Brucella spp. can infect humans through inhalation, their ability to induce CCL20 and hBD2 in lung cells is unknown. Here we show that B. abortus induces CCL20 expression in human alveolar (A549) or bronchial (Calu-6) epithelial cell lines, primary alveolar epithelial cells, primary human monocytes, monocyte-derived macrophages and the monocytic cell line THP-1. CCL20 expression was mainly mediated by JNK1/2 and NF-kB in both Calu-6 and THP-1 cells. CCL20 secretion was markedly induced in A549, Calu-6 and THP-1 cells by heat-killed B. abortus or a model Brucella lipoprotein (L-Omp19) but not by the B. abortus lipopolysaccharide (LPS). Accordingly, CCL20 production by B. abortus-infected cells was strongly TLR2-dependent. Whereas hBD2 expression was not induced by B. abortus infection, it was significantly induced in A549 cells by conditioned media from B. abortus-infected THP-1 monocytes (CMB). A similar inducing effect was observed on CCL20 secretion. Experiments using blocking agents revealed that IL-1β, but not TNF-α, was involved in the induction of hBD2 and CCL20 secretion by CMB. In the in vitro antimicrobial assay, the lethal dose (LD) 50 of CCL20 for B. abortus (>50 μg/ml) was markedly higher than that against E. coli (1.5 μg/ml) or a B. abortus mutant lacking the O polysaccharide in its LPS (8.7 ug/ml). hBD2 did not kill any of the B. abortus strains at the tested concentrations. These results show that human lung epithelial cells secrete CCL20 and hBD2 in response to B. abortus and/or to cytokines produced by infected monocytes. Whereas these molecules do not seem to exert antimicrobial activity against this pathogen, they could recruit immune cells to the infection site. PMID:26448160

Differential activity of innate defense antimicrobial peptides against Nocardia species.

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Rieg, Siegbert; Meier, Benjamin; Fähnrich, Eva; Huth, Anja; Wagner, Dirk; Kern, Winfried V; Kalbacher, Hubert

2010-02-23

Members of the genus Nocardia are ubiquitous environmental saprophytes capable to cause human pulmonary, disseminated and cutaneous nocardiosis or bovine mastitis. Innate immunity appears to play an important role in early defense against Nocardia species. To elucidate the contribution of antimicrobial peptides (AMPs) in innate defense against Nocardia, the activity of human alpha-defensins human neutrophil peptides (HNPs) 1-3, human beta-defensin (hBD)-3 and cathelicidin LL-37 as well as bovine beta-defensins lingual and tracheal antimicrobial peptides (LAP, TAP) and bovine neutrophil-derived indolicidin against four important Nocardia species was investigated. Whereas N. farcinica ATCC 3318 and N. nova ATCC 33726 were found to be susceptible to all investigated human and bovine AMPs, N. asteroides ATCC 19247 was killed exclusively by neutrophil-derived human alpha-defensins HNP 1-3 and bovine indolicidin. N. brasiliensis ATCC 19296 was found to exhibit complete resistance to investigated human AMPs and to be susceptible only to bovine indolicidin. Selected AMPs are capable to contribute to the first line of defense against Nocardia, yet, susceptibility appears to vary across different Nocardia species. Obtained results of neutrophil-derived AMPs to possess the broadest antinocardial spectrum are remarkable, since nocardiosis is characterized by a neutrophil-rich infiltrate in vivo.

Differential activity of innate defense antimicrobial peptides against Nocardia species

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Wagner Dirk

2010-02-01

Full Text Available Abstract Background Members of the genus Nocardia are ubiquitous environmental saprophytes capable to cause human pulmonary, disseminated and cutaneous nocardiosis or bovine mastitis. Innate immunity appears to play an important role in early defense against Nocardia species. To elucidate the contribution of antimicrobial peptides (AMPs in innate defense against Nocardia, the activity of human α-defensins human neutrophil peptides (HNPs 1-3, human β-defensin (hBD-3 and cathelicidin LL-37 as well as bovine β-defensins lingual and tracheal antimicrobial peptides (LAP, TAP and bovine neutrophil-derived indolicidin against four important Nocardia species was investigated. Results Whereas N. farcinica ATCC 3318 and N. nova ATCC 33726 were found to be susceptible to all investigated human and bovine AMPs, N. asteroides ATCC 19247 was killed exclusively by neutrophil-derived human α-defensins HNP 1-3 and bovine indolicidin. N. brasiliensis ATCC 19296 was found to exhibit complete resistance to investigated human AMPs and to be susceptible only to bovine indolicidin. Conclusion Selected AMPs are capable to contribute to the first line of defense against Nocardia, yet, susceptibility appears to vary across different Nocardia species. Obtained results of neutrophil-derived AMPs to possess the broadest antinocardial spectrum are remarkable, since nocardiosis is characterized by a neutrophil-rich infiltrate in vivo.

Should we stop thinking about inhibition? Searching for individual and age differences in inhibition ability.

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Rey-Mermet, Alodie; Gade, Miriam; Oberauer, Klaus

2018-04-01

Inhibition is often conceptualized as a unitary construct reflecting the ability to ignore and suppress irrelevant information. At the same time, it has been subdivided into inhibition of prepotent responses (i.e., the ability to stop dominant responses) and resistance to distracter interference (i.e., the ability to ignore distracting information). The present study investigated the unity and diversity of inhibition as a psychometric construct, and tested the hypothesis of an inhibition deficit in older age. We measured inhibition in young and old adults with 11 established laboratory tasks: antisaccade, stop-signal, color Stroop, number Stroop, arrow flanker, letter flanker, Simon, global-local, positive and negative compatibility tasks, and n-2 repetition costs in task switching. In both age groups, the inhibition measures from individual tasks had good reliabilities, but correlated only weakly among each other. Structural equation modeling identified a 2-factor model with factors for inhibition of prepotent responses and resistance to distracter interference. Older adults scored worse in the inhibition of prepotent response, but better in the resistance to distracter interference. However, the model had low explanatory power. Together, these findings call into question inhibition as a psychometric construct and the hypothesis of an inhibition deficit in older age. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Ionizable polyethers as specific metal ion carriers in liquid-liquid extraction and liquid membrane separations

International Nuclear Information System (INIS)

Walkowiak, W.; Charewicz, W.A.; Bartsch, R.A.; Ndip, G.M.

1988-01-01

Consideration is given to results of investigations into competitive extraction and penetration through a liquid membrane of alkali and alkaline earth cations from aqueous solutions by a series of lipophilic and ionizable acyclic polyethers of various molecular structure. It is shown that specificity and selectiviy of cation carriers in liquid-liquid extraction and liquid membrane separation depend on molecular structure of acyclic polyethers

Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants.

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Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

2016-01-08

Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity.

Potential roles of placental human beta-defensin-3 and apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G in prevention of intrauterine transmission of hepatitis B virus.

Science.gov (United States)

Bai, Xiaoxia; Tian, Ting; Wang, Peng; Yang, Xiaofu; Wang, Zhengping; Dong, Minyue

2015-03-01

Approximately 5% of newborns were infected by hepatitis B virus (HBV) via intrauterine transmission and this is the main reason for high prevalence of HBV in endemic regions. However, the mechanisms by which intrauterine transmission is avoided in most cases remain elusive and placental natural anti-microbial factors may play a role in the prevention of HBV intrauterine transmission. The expression levels of human β-defensin-3 (HBD-3), apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G (A3G) and mannose binding lectin (MBL) were determined in the placenta of 30 HBV-seronegative pregnant women (controls), 7 HBV-seropositive pregnant women with infants infected via intrauterine transmission (infected group) and 30 HBV-seropositive pregnant women with non-infected infants (non-infected group). The expression of HBD-3, A3G, and MBL of placental trophoblast cell line Swan71 was determined after exposed to HBV. There were significant differences in placental HBD-3 and A3G levels among three groups, but the expression of MBL did not significantly differ. The expressions of HBD-3 and A3G were higher in non-infected group than controls and infected group, but not significantly different between infected group and controls. The exposure to HBV increased significantly the expression of HBD-3, A3G, and MBL by Swan 71. It may be concluded HBV up-regulates HBD-3 and A3G expression in vivo and in vitro in placental trophoblast and lack of this up-regulation is possibly associated with intrauterine transmission of HBV. © 2014 Wiley Periodicals, Inc.

Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin

International Nuclear Information System (INIS)

Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng; Hwang, Jae Sam; Seok, Heon; Choi, Hyemin; Lee, Dong Gun; Kim, Jae Il; Kim, Ho

2014-01-01

Highlights: • 11-mer peptide Lumbricusin, a defensin like peptide, is isolated from earthworm. • We here demonstrated that Lumbricusin has neurotropic and neuroprotective effects. • p27 degradation by Lumbricusin mediates effects of Lumbricusin on neuronal cells. - Abstract: We recently isolated a polypeptide from the earthworm Lumbricus terrestris that is structurally similar to defensin, a well-known antibacterial peptide. An 11-mer antibacterial peptide (NH 2 -RNRRWCIDQQA), designated Lumbricusin, was synthesized based on the amino acid sequence of the isolated polypeptide. Since we previously reported that CopA3, a dung beetle peptide, enhanced neuronal cell proliferation, we here examined whether Lumbricusin exerted neurotropic and/or neuroprotective effects. Lumbricusin treatment induced a time-dependent increase (∼51%) in the proliferation of human neuroblastoma SH-SY5Y cells. Lumbricusin also significantly inhibited the apoptosis and decreased viability induced by treatment with 6-hydroxy dopamine, a Parkinson’s disease-mimicking agent. Immunoblot analyses revealed that Lumbricusin treatment increased ubiquitination of p27 Kip1 protein, a negative regulator of cell-cycle progression, in SH-SY5Y cells, and markedly promoted its degradation. Notably, adenoviral-mediated over-expression of p27 Kip1 significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27 Kip1 degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin

Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin

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Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of); Hwang, Jae Sam [Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon 441-707 (Korea, Republic of); Seok, Heon [Department of Biomedical Engineering, Jungwon University, Goesan, Chungcheongbukdo 367-700 (Korea, Republic of); Choi, Hyemin; Lee, Dong Gun [School of Life Sciences, KNU Creative Bioresearch Group (BK21 Plus Program), College of Natural Sciences, Kyungpook National University, Daehak-ro 80, Buk-gu, Daegu 702-701 (Korea, Republic of); Kim, Jae Il [School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Kim, Ho, E-mail: hokim@daejin.ac.kr [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of)

2014-06-06

Highlights: • 11-mer peptide Lumbricusin, a defensin like peptide, is isolated from earthworm. • We here demonstrated that Lumbricusin has neurotropic and neuroprotective effects. • p27 degradation by Lumbricusin mediates effects of Lumbricusin on neuronal cells. - Abstract: We recently isolated a polypeptide from the earthworm Lumbricus terrestris that is structurally similar to defensin, a well-known antibacterial peptide. An 11-mer antibacterial peptide (NH{sub 2}-RNRRWCIDQQA), designated Lumbricusin, was synthesized based on the amino acid sequence of the isolated polypeptide. Since we previously reported that CopA3, a dung beetle peptide, enhanced neuronal cell proliferation, we here examined whether Lumbricusin exerted neurotropic and/or neuroprotective effects. Lumbricusin treatment induced a time-dependent increase (∼51%) in the proliferation of human neuroblastoma SH-SY5Y cells. Lumbricusin also significantly inhibited the apoptosis and decreased viability induced by treatment with 6-hydroxy dopamine, a Parkinson’s disease-mimicking agent. Immunoblot analyses revealed that Lumbricusin treatment increased ubiquitination of p27{sup Kip1} protein, a negative regulator of cell-cycle progression, in SH-SY5Y cells, and markedly promoted its degradation. Notably, adenoviral-mediated over-expression of p27{sup Kip1} significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27{sup Kip1} degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin.

Behavioral inhibition and obsessive-compulsive disorder.

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Coles, Meredith E; Schofield, Casey A; Pietrefesa, Ashley S

2006-01-01

Behavioral inhibition is frequently cited as a vulnerability factor for development of anxiety. However, few studies have examined the unique relationship between behavioral inhibition and obsessive-compulsive disorder (OCD). Therefore, the current study addressed the relationship between behavioral inhibition and OCD in a number of ways. In a large unselected student sample, frequency of current OC symptoms was significantly correlated with retrospective self-reports of total levels of childhood behavioral inhibition. In addition, frequency of current OC symptoms was also significantly correlated with both social and nonsocial components of behavioral inhibition. Further, there was evidence for a unique relationship between behavioral inhibition and OC symptoms beyond the relationship of behavioral inhibition and social anxiety. In addition, results showed that reports of childhood levels of behavioral inhibition significantly predicted levels of OCD symptoms in adulthood. Finally, preliminary evidence suggested that behavioral inhibition may be more strongly associated with some types of OC symptoms than others, and that overprotective parenting may moderate the impact of behavioral inhibition on OC symptoms. The current findings suggest the utility of additional research examining the role of behavioral inhibition in the etiology of OCD.

I-FABP as biomarker for the early diagnosis of acute mesenteric ischemia and resultant lung injury.

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Rachel G Khadaroo

Full Text Available Acute mesenteric ischemia (AMI is a life-threatening condition that can result in multiple organ injury and death. A timely diagnosis and treatment would have a significant impact on the morbidity and mortality in high-risk patient population. The purpose of this study was to investigate if intestinal fatty acid binding protein (I-FABP and α-defensins can be used as biomarkers for early AMI and resultant lung injury. C57BL/6 mice were subjected to intestinal ischemia by occlusion of the superior mesenteric artery. A time course of intestinal ischemia from 0.5 to 3 h was performed and followed by reperfusion for 2 h. Additional mice were treated with N-acetyl-cysteine (NAC at 300 mg/kg given intraperitoneally prior to reperfusion. AMI resulted in severe intestinal injury characterized by neutrophil infiltrate, myeloperoxidase (MPO levels, cytokine/chemokine levels, and tissue histopathology. Pathologic signs of ischemia were evident at 1 h, and by 3 h of ischemia, the full thickness of the intestine mucosa had areas of coagulative necrosis. It was noted that the levels of α-defensins in intestinal tissue peaked at 1 h and I-FABP in plasma peaked at 3 h after AMI. Intestinal ischemia also resulted in lung injury in a time-dependent manner. Pretreatment with NAC decreased the levels of intestinal α-defensins and plasma I-FABP, as well as lung MPO and cytokines. In summary, the concentrations of intestinal α-defensins and plasma I-FABP predicted intestinal ischemia prior to pathological evidence of ischemia and I-FABP directly correlated with resultant lung injury. The antioxidant NAC reduced intestinal and lung injury induced by AMI, suggesting a role for oxidants in the mechanism for distant organ injury. I-FABP and α-defensins are promising biomarkers, and may guide the treatment with antioxidant in early intestinal and distal organ injury.

Inhibition of polyphenoloxidase by sulfite

International Nuclear Information System (INIS)

Sayavedra-Soto, L.A.; Montgomery, M.W.

1986-01-01

When polyphenoloxidase (PPO) was exposed to sulfite prior to substrate addition, inhibition was irreversible. Trials to regenerate PPO activity, using extensive dialysis, column chromatography, and addition of copper salts were not successful. Increased concentrations of sulfite and pH levels less than 5 enhanced the inhibition of PPO by sulfite. At pH 4, concentrations greater than 0.04 mg/mL completely inhibited 1000 units of PPO activity almost instantaneously. This suggested that the HSO 3 - molecule was the main component in the sulfite system inhibiting PPO. Column chromatography, extensive dialysis, and gel electrophoresis did not demonstrate 35 SO 2 bound to purified pear PPO protein. Formation of extra protein bands of sulfite inhibited purified pear PPO fractions on gel electrophoresis was demonstrated. This and other evidence suggested that the major mode of direct irreversible inhibition of PPO was modification of the protein structure, with retention of its molecular unity

Loop Replacement Enhances the Ancestral Antibacterial Function of a Bifunctional Scorpion Toxin

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Shangfei Zhang

2018-06-01

Full Text Available On the basis of the evolutionary relationship between scorpion toxins targeting K+ channels (KTxs and antibacterial defensins (Zhu S., Peigneur S., Gao B., Umetsu Y., Ohki S., Tytgat J. Experimental conversion of a defensin into a neurotoxin: Implications for origin of toxic function. Mol. Biol. Evol. 2014, 31, 546–559, we performed protein engineering experiments to modify a bifunctional KTx (i.e., weak inhibitory activities on both K+ channels and bacteria via substituting its carboxyl loop with the structurally equivalent loop of contemporary defensins. As expected, the engineered peptide (named MeuTXKα3-KFGGI remarkably improved the antibacterial activity, particularly on some Gram-positive bacteria, including several antibiotic-resistant opportunistic pathogens. Compared with the unmodified toxin, its antibacterial spectrum also enlarged. Our work provides a new method to enhance the antibacterial activity of bifunctional scorpion venom peptides, which might be useful in engineering other proteins with an ancestral activity.

Inhibition of photosynthesis by carbon monoxide and suspension of the carbon monoxide inhibition by light

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Gewitz, H S; Voelker, W

1963-08-01

The experimental subject was the autotroph Chlorella pyrenoidosa. It was found that growth conditions determine whether the alga is inhibited by carbon monoxide or not. Respiration and photosynthesis are inhibited by carbon monoxide if the cells have grown rapidly under high light intensities. The inhibition of respiration and photosynthesis found in such cells is completely reversible. The inhibition depends not only on carbon monoxide pressure, but also on the oxygen pressure prevailing at the same time. 5 references, 1 figure, 3 tables.

Insect antimicrobial peptides act synergistically to inhibit a trypanosome parasite.

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Marxer, Monika; Vollenweider, Vera; Schmid-Hempel, Paul

2016-05-26

The innate immune system provides protection from infection by producing essential effector molecules, such as antimicrobial peptides (AMPs) that possess broad-spectrum activity. This is also the case for bumblebees, Bombus terrestris, when infected by the trypanosome, Crithidia bombi Furthermore, the expressed mixture of AMPs varies with host genetic background and infecting parasite strain (genotype). Here, we used the fact that clones of C. bombi can be cultivated and kept as strains in medium to test the effect of various combinations of AMPs on the growth rate of the parasite. In particular, we used pairwise combinations and a range of physiological concentrations of three AMPs, namely Abaecin, Defensin and Hymenoptaecin, synthetized from the respective genomic sequences. We found that these AMPs indeed suppress the growth of eight different strains of C. bombi, and that combinations of AMPs were typically more effective than the use of a single AMP alone. Furthermore, the most effective combinations were rarely those consisting of maximum concentrations. In addition, the AMP combination treatments revealed parasite strain specificity, such that strains varied in their sensitivity towards the same mixtures. Hence, variable expression of AMPs could be an alternative strategy to combat highly variable infections.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

Anti-Bacterial Activity of Recombinant Human β-Defensin-3 Secreted in the Milk of Transgenic Goats Produced by Somatic Cell Nuclear Transfer

Science.gov (United States)

Han, Chengquan; Zhang, Hui; Wang, Yongsheng; Su, Jianmin; Quan, Fusheng; Gao, Mingqing; Zhang, Yong

2013-01-01

The present study was conducted to determine whether recombinant human β-defensin-3 (rHBD3) in the milk of transgenic goats has an anti-bacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Streptococcus agalactiae (S. agalactiae) that could cause mastitis. A HBD3 mammary-specific expression vector was transfected by electroporation into goat fetal fibroblasts which were used to produce fourteen healthy transgenic goats by somatic cell nuclear transfer. The expression level of rHBD3 in the milk of the six transgenic goats ranged from 98 to 121 µg/ml at 15 days of lactation, and was maintained at 90–111 µg/ml during the following 2 months. Milk samples from transgenic goats showed an obvious inhibitory activity against E. coli, S. aureus and S. agalactiae in vitro. The minimal inhibitory concentrations of rHBD3 in milk against E. coli, S. aureus and S. agalactiae were 9.5–10.5, 21.8–23.0 and 17.3–18.5 µg/mL, respectively, which was similar to those of the HBD3 standard (P>0.05). The in vivo anti-bacterial activities of rHBD3 in milk were examined by intramammary infusion of viable bacterial inoculums. We observed that 9/10 and 8/10 glands of non-transgenic goats infused with S. aureus and E. coli became infected. The mean numbers of viable bacteria went up to 2.9×103 and 95.4×103 CFU/ml at 48 h after infusion, respectively; the mean somatic cell counts (SCC) in infected glands reached up to 260.4×105 and 622.2×105 cells/ml, which were significantly higher than the SCC in uninfected goat glands. In contrast, no bacteria was presented in glands of transgenic goats and PBS-infused controls, and the SSC did not significantly change throughout the period. Moreover, the compositions and protein profiles of milk from transgenic and non-transgenic goats were identical. The present study demonstrated that HBD3 were an effective anti-bacterial protein to enhance the mastitis resistance of dairy animals. PMID:23799010

Corrosion inhibition

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Fisher, A O

1965-12-29

An acid corrosion-inhibiting composition consists essentially of a sugar, and an alkali metal salt selected from the group consisting of iodides and bromides. The weight ratio of the sugar to the alkali metal salt is between 2:1 and about 20,000:1. Also, a corrosion- inhibited phosphoric acid composition comprising at least about 20 wt% of phosphoric acid and between about 0.1 wt% and about 10 wt% of molasses, and between about 0.0005 wt% and about 1 wt% of potassium iodide. The weight ratio of molasses to iodide is greater than about 2:1. (11 claims)

Inhibition of MMPs by alcohols

Science.gov (United States)

Tezvergil-Mutluay, Arzu; Agee, Kelli A.; Hoshika, Tomohiro; Uchiyama, Toshikazu; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; Thompson, Jeremy M.; McCracken, Courtney E.; Looney, Stephen W.; Tay, Franklin R.; Pashley, David H.

2011-01-01

Objectives While screening the activity of potential inhibitors of matrix metalloproteinases (MMPs), due to the limited water solubility of some of the compounds, they had to be solubilized in ethanol. When ethanol solvent controls were run, they were found to partially inhibit MMPs. Thus, the purpose of this study was to compare the MMP-inhibitory activity of a series of alcohols. Methods The possible inhibitory activity of a series of alcohols was measured against soluble rhMMP-9 and insoluble matrix-bound endogenous MMPs of dentin in completely demineralized dentin. Increasing concentrations (0.17, 0.86, 1.71 and 4.28 moles/L) of a homologous series of alcohols (i.e. methanol, ethanol, propanols, butanols, pentanols, hexanols, the ethanol ester of methacrylic acid, heptanols and octanol) were compared to ethanediol, and propanediol by regression analysis to calculate the molar concentration required to inhibit MMPs by 50% (i.e. the IC50). Results Using two different MMP models, alcohols were shown to inhibit rhMMP-9 and the endogenous proteases of dentin matrix in a dose-dependent manner. The degree of MMP inhibition by alcohols increased with chain length up to 4 methylene groups. Based on the molar concentration required to inhibit rhMMP-9 fifty percent, 2-hydroxyethylmethacrylate (HEMA), 3-hexanol, 3-heptanol and 1-octanol gave the strongest inhibition. Significance The results indicate that alcohols with 4 methylene groups inhibit MMPs more effectively than methanol or ethanol. MMP inhibition was inversely related to the Hoy's solubility parameter for hydrogen bonding forces of the alcohols (i.e. to their hydrophilicity). PMID:21676453

Equol inhibits growth, induces atresia, and inhibits steroidogenesis of mouse antral follicles in vitro

International Nuclear Information System (INIS)

Mahalingam, Sharada; Gao, Liying; Gonnering, Marni; Helferich, William; Flaws, Jodi A.

2016-01-01

Equol is a non-steroidal estrogen metabolite produced by microbial conversion of daidzein, a major soy isoflavone, in the gut of some humans and many animal species. Isoflavones and their metabolites can affect endogenous estradiol production, action, and metabolism, potentially influencing ovarian follicle function. However, no studies have examined the effects of equol on intact ovarian antral follicles, which are responsible for sex steroid synthesis and further development into ovulatory follicles. Thus, the present study tested the hypothesis that equol inhibits antral follicle growth, increases follicle atresia, and inhibits steroidogenesis in the adult mouse ovary. To test this hypothesis, antral follicles isolated from adult CD-1 mice were cultured with vehicle control (dimethyl sulfoxide; DMSO) or equol (600 nM, 6 μM, 36 μM, and 100 μM) for 48 and 96 h. Every 24 h, follicle diameters were measured to monitor growth. At 48 and 96 h, the culture medium was subjected to measurement of hormone levels, and the cultured follicles were subjected to gene expression analysis. Additionally, follicles were histologically evaluated for signs of atresia after 96 h of culture. The results indicate that equol (100 μM) inhibited follicle growth, altered the mRNA levels of bcl2-associated X protein and B cell leukemia/lymphoma 2, and induced follicle atresia. Further, equol decreased the levels of estradiol, testosterone, androstenedione, and progesterone, and it decreased mRNA levels of cholesterol side-chain cleavage, steroid 17-α-hydroxalase, and aromatase. Collectively, these data indicate that equol inhibits growth, increases atresia, and inhibits steroidogenesis of cultured mouse antral follicles. - Highlights: • Equol exposure inhibits antral follicle growth. • Equol exposure increases follicle atresia. • Equol exposure inhibits sex steroid hormone levels. • Equol exposure inhibits mRNA levels of certain steroidogenic enzymes.

Equol inhibits growth, induces atresia, and inhibits steroidogenesis of mouse antral follicles in vitro

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Mahalingam, Sharada, E-mail: mahalin2@illinois.edu [Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States); Gao, Liying, E-mail: lgao@uiuc.edu [Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States); Gonnering, Marni, E-mail: mgonne2@illinois.edu [Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States); Helferich, William, E-mail: helferic@illinois.edu [Department of Food Science and Human Nutrition, University of Illinois, 905 S. Goodwin, Urbana, IL 61801 (United States); Flaws, Jodi A., E-mail: jflaws@illinois.edu [Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802 (United States)

2016-03-15

Equol is a non-steroidal estrogen metabolite produced by microbial conversion of daidzein, a major soy isoflavone, in the gut of some humans and many animal species. Isoflavones and their metabolites can affect endogenous estradiol production, action, and metabolism, potentially influencing ovarian follicle function. However, no studies have examined the effects of equol on intact ovarian antral follicles, which are responsible for sex steroid synthesis and further development into ovulatory follicles. Thus, the present study tested the hypothesis that equol inhibits antral follicle growth, increases follicle atresia, and inhibits steroidogenesis in the adult mouse ovary. To test this hypothesis, antral follicles isolated from adult CD-1 mice were cultured with vehicle control (dimethyl sulfoxide; DMSO) or equol (600 nM, 6 μM, 36 μM, and 100 μM) for 48 and 96 h. Every 24 h, follicle diameters were measured to monitor growth. At 48 and 96 h, the culture medium was subjected to measurement of hormone levels, and the cultured follicles were subjected to gene expression analysis. Additionally, follicles were histologically evaluated for signs of atresia after 96 h of culture. The results indicate that equol (100 μM) inhibited follicle growth, altered the mRNA levels of bcl2-associated X protein and B cell leukemia/lymphoma 2, and induced follicle atresia. Further, equol decreased the levels of estradiol, testosterone, androstenedione, and progesterone, and it decreased mRNA levels of cholesterol side-chain cleavage, steroid 17-α-hydroxalase, and aromatase. Collectively, these data indicate that equol inhibits growth, increases atresia, and inhibits steroidogenesis of cultured mouse antral follicles. - Highlights: • Equol exposure inhibits antral follicle growth. • Equol exposure increases follicle atresia. • Equol exposure inhibits sex steroid hormone levels. • Equol exposure inhibits mRNA levels of certain steroidogenic enzymes.

Self-regulation, ego depletion, and inhibition.

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Baumeister, Roy F

2014-12-01

Inhibition is a major form of self-regulation. As such, it depends on self-awareness and comparing oneself to standards and is also susceptible to fluctuations in willpower resources. Ego depletion is the state of reduced willpower caused by prior exertion of self-control. Ego depletion undermines inhibition both because restraints are weaker and because urges are felt more intensely than usual. Conscious inhibition of desires is a pervasive feature of everyday life and may be a requirement of life in civilized, cultural society, and in that sense it goes to the evolved core of human nature. Intentional inhibition not only restrains antisocial impulses but can also facilitate optimal performance, such as during test taking. Self-regulation and ego depletion- may also affect less intentional forms of inhibition, even chronic tendencies to inhibit. Broadly stated, inhibition is necessary for human social life and nearly all societies encourage and enforce it. Copyright © 2014 Elsevier Ltd. All rights reserved.

Engineering blood meal-activated systemic immunity in the yellow fever mosquito, Aedes aegypti.

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Kokoza, V; Ahmed, A; Cho, W L; Jasinskiene, N; James, A A; Raikhel, A

2000-08-01

Progress in molecular genetics makes possible the development of alternative disease control strategies that target the competence of mosquitoes to transmit pathogens. We tested the regulatory region of the vitellogenin (Vg) gene of Aedes aegypti for its ability to express potential antipathogen factors in transgenic mosquitoes. Hermes-mediated transformation was used to integrate a 2.1-kb Vg-promoter fragment driving the expression of the Defensin A (DefA) coding region, one of the major insect immune factors. PCR amplification of genomic DNA and Southern blot analyses, carried out through the ninth generation, showed that the Vg-DefA transgene insertion was stable. The Vg-DefA transgene was strongly activated in the fat body by a blood meal. The mRNA levels reached a maximum at 24-h postblood meal, corresponding to the peak expression time of the endogenous Vg gene. High levels of transgenic defensin were accumulated in the hemolymph of bloodfed female mosquitoes, persisting for 20-22 days after a single blood feeding. Purified transgenic defensin showed antibacterial activity comparable to that of defensin isolated from bacterially challenged control mosquitoes. Thus, we have been able to engineer the genetically stable transgenic mosquito with an element of systemic immunity, which is activated through the blood meal-triggered cascade rather than by infection. This work represents a significant step toward the development of molecular genetic approaches to the control of vector competence in pathogen transmission.

Varroa destructor induces changes in the expression of immunity-related genes during the development of Apis mellifera worker and drone broods.

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Zaobidna, Ewa A; Żółtowska, Krystyna; Łopieńska-Biernat, Elżbieta

2017-12-20

The ectoparasitic mite Varroa destructor has emerged as the major pest of honeybees. Despite extensive research efforts, the pathogenesis of varroosis has not been fully explained. Earlier studies suggested that V. destructor infestation leads to the suppression of the host's immune system. The aim of this study was to analyze the immune responses of 14 genes in the Toll signal transduction pathways, including effector genes of antimicrobial peptides (AMPs), in developing Apis mellifera workers and drones infested with V. destructor. Four developmental stages (L5 larvae, prepupae, and 2 pupal stages) and newly emerged imagines were analyzed. In workers, the most significant changes were observed in L5 larvae in the initial stages of infestation. A significant increase in the relative expression of 10 of the 14 analyzed genes, including defensin-1 and defensin-2, was observed in infested bees relative to non-infested individuals. The immune response in drones developed at a slower rate. The expression of genes regulating cytoplasmic signal transduction increased in prepupae, whereas the expression of defensin-1 and defensin-2 effector genes increased in P3 pupae with red eyes. The expression of many immunity-related genes was silenced in successive life stages and in imagines, and it was more profound in workers than in drones. The results indicate that V. destructor significantly influences immune responses regulated by the Toll signal transduction pathway in bees. In infested bees, the observed changes in Toll pathway genes varied between life stages and the sexes.

Fear inhibition in high trait anxiety.

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Merel Kindt

Full Text Available Trait anxiety is recognized as an individual risk factor for the development of anxiety disorders but the neurobiological mechanisms remain unknown. Here we test whether trait anxiety is associated with impaired fear inhibition utilizing the AX+/BX- conditional discrimination procedure that allows for the independent evaluation of startle fear potentiation and inhibition of fear. Sixty undergraduate students participated in the study--High Trait Anxious: n = 28 and Low Trait Anxious: n = 32. We replicated earlier findings that a transfer of conditioned inhibition for startle responses requires contingency awareness. However, contrary to the fear inhibition hypothesis, our data suggest that high trait anxious individuals show a normal fear inhibition of conditioned startle responding. Only at the cognitive level the high trait anxious individuals showed evidence for impaired inhibitory learning of the threat cue. Together with other findings where impaired fear inhibition was only observed in those PTSD patients who were either high on hyperarousal symptoms or with current anxiety symptoms, we question whether impaired fear inhibition is a biomarker for the development of anxiety disorders.

A compensatory mutation provides resistance to disparate HIV fusion inhibitor peptides and enhances membrane fusion.

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Matthew P Wood

Full Text Available Fusion inhibitors are a class of antiretroviral drugs used to prevent entry of HIV into host cells. Many of the fusion inhibitors being developed, including the drug enfuvirtide, are peptides designed to competitively inhibit the viral fusion protein gp41. With the emergence of drug resistance, there is an increased need for effective and unique alternatives within this class of antivirals. One such alternative is a class of cyclic, cationic, antimicrobial peptides known as θ-defensins, which are produced by many non-human primates and exhibit broad-spectrum antiviral and antibacterial activity. Currently, the θ-defensin analog RC-101 is being developed as a microbicide due to its specific antiviral activity, lack of toxicity to cells and tissues, and safety in animals. Understanding potential RC-101 resistance, and how resistance to other fusion inhibitors affects RC-101 susceptibility, is critical for future development. In previous studies, we identified a mutant, R5-tropic virus that had evolved partial resistance to RC-101 during in vitro selection. Here, we report that a secondary mutation in gp41 was found to restore replicative fitness, membrane fusion, and the rate of viral entry, which were compromised by an initial mutation providing partial RC-101 resistance. Interestingly, we show that RC-101 is effective against two enfuvirtide-resistant mutants, demonstrating the clinical importance of RC-101 as a unique fusion inhibitor. These findings both expand our understanding of HIV drug-resistance to diverse peptide fusion inhibitors and emphasize the significance of compensatory gp41 mutations.

Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

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Hill, David R.; Rho, Hyunjin K.; Kessler, Sean P.; Amin, Ripal; Homer, Craig R.; McDonald, Christine; Cowman, Mary K.; de la Motte, Carol A.

2013-01-01

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

Th17 cells and IL-17 in protective immunity to vaginal candidiasis.

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Pietrella, Donatella; Rachini, Anna; Pines, Mark; Pandey, Neelam; Mosci, Paolo; Bistoni, Francesco; d'Enfert, Cristophe; Vecchiarelli, Anna

2011-01-01

Th17 cells play a major role in coordinating the host defence in oropharyngeal candidiasis. In this study we investigated the involvement of the Th17 response in an animal model of vulvovaginal candidiasis (VVC). To monitor the course of infection we exploited a new in vivo imaging technique. i) The progression of VVC leads to a strong influx of neutrophils in the vagina soon after the challenge which persisted despite the resolution of infection; ii) IL-17, produced by vaginal cells, particularly CD4 T cells, was detected in the vaginal wash during the infection, reaching a maximum 14 days after the challenge; iii) The amount and kinetics of IL-23 in vaginal fluids were comparable to those in vaginal cells; iv) The inhibition of Th17 differentiation led to significant inhibition of IL-17 production with consequent exacerbation of infection; v) An increased production of βdefensin 2 was manifested in cells of infected mice. This production was strongly reduced when Th17 differentiation was inhibited and was increased by rIL-17 treatment. These results imply that IL-17 and Th17, along with innate antimicrobial factors, have a role in the immune response to vaginal candidiasis.

Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis.

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Li, Qingli; Lambrechts, Mark J; Zhang, Qiuyang; Liu, Sen; Ge, Dongxia; Yin, Rutie; Xi, Mingrong; You, Zongbing

2013-01-01

Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose) polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy.

Allosteric Inhibition of Factor XIIIa. Non-Saccharide Glycosaminoglycan Mimetics, but Not Glycosaminoglycans, Exhibit Promising Inhibition Profile.

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Rami A Al-Horani

Full Text Available Factor XIIIa (FXIIIa is a transglutaminase that catalyzes the last step in the coagulation process. Orthostery is the only approach that has been exploited to design FXIIIa inhibitors. Yet, allosteric inhibition of FXIIIa is a paradigm that may offer a key advantage of controlled inhibition over orthosteric inhibition. Such an approach is likely to lead to novel FXIIIa inhibitors that do not carry bleeding risks. We reasoned that targeting a collection of basic amino acid residues distant from FXIIIa's active site by using sulfated glycosaminoglycans (GAGs or non-saccharide GAG mimetics (NSGMs would lead to the discovery of the first allosteric FXIIIa inhibitors. We tested a library of 22 variably sulfated GAGs and NSGMs against human FXIIIa to discover promising hits. Interestingly, although some GAGs bound to FXIIIa better than NSGMs, no GAG displayed any inhibition. An undecasulfated quercetin analog was found to inhibit FXIIIa with reasonable potency (efficacy of 98%. Michaelis-Menten kinetic studies revealed an allosteric mechanism of inhibition. Fluorescence studies confirmed close correspondence between binding affinity and inhibition potency, as expected for an allosteric process. The inhibitor was reversible and at least 9-fold- and 26-fold selective over two GAG-binding proteins factor Xa (efficacy of 71% and thrombin, respectively, and at least 27-fold selective over a cysteine protease papain. The inhibitor also inhibited the FXIIIa-mediated polymerization of fibrin in vitro. Overall, our work presents the proof-of-principle that FXIIIa can be allosterically modulated by sulfated non-saccharide agents much smaller than GAGs, which should enable the design of selective and safe anticoagulants.

Naturally Occurring Missense MRGPRX2 Variants Display Loss of Function Phenotype for Mast Cell Degranulation in Response to Substance P, Hemokinin-1, Human β-Defensin-3, and Icatibant.

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Alkanfari, Ibrahim; Gupta, Kshitij; Jahan, Tahsin; Ali, Hydar

2018-05-23

Human mast cells (MCs) express a novel G protein-coupled receptor (GPCR) known as Mas-related GPCR X2 (MRGPRX2). Activation of this receptor by a diverse group of cationic ligands such as neuropeptides, host defense peptides, and Food and Drug Administration-approved drugs contributes to chronic inflammatory diseases and pseudoallergic drug reactions. For most GPCRs, the extracellular (ECL) domains and their associated transmembrane (TM) domains display the greatest structural diversity and are responsible for binding different ligands. The goal of the current study was to determine if naturally occurring missense variants within MRGPRX2's ECL/TM domains contribute to gain or loss of function phenotype for MC degranulation in response to neuropeptides (substance P and hemokinin-1), a host defense peptide (human β-defensin-3) and a Food and Drug Administration-approved cationic drug (bradykinin B2 receptor antagonist, icatibant). We have identified eight missense variants within MRGPRX2's ECL/TM domains from publicly available exome-sequencing databases. We investigated the ability of MRGPRX2 ligands to induce degranulation in rat basophilic leukemia-2H3 cells individually expressing these naturally occurring MRGPRX2 missense variants. Using stable and transient transfections, we found that all variants express in rat basophilic leukemia cells. However, four natural MRGPRX2 variants, G165E (rs141744602), D184H (rs372988289), W243R (rs150365137), and H259Y (rs140862085) failed to respond to any of the ligands tested. Thus, diverse MRGPRX2 ligands use common sites on the receptor to induce MC degranulation. These findings have important clinical implications for MRGPRX2 and MC-mediated pseudoallergy and chronic inflammatory diseases. Copyright © 2018 by The American Association of Immunologists, Inc.

Selective inhibition of distracting input.

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Noonan, MaryAnn P; Crittenden, Ben M; Jensen, Ole; Stokes, Mark G

2017-10-16

We review a series of studies exploring distractor suppression. It is often assumed that preparatory distractor suppression is controlled via top-down mechanisms of attention akin to those that prepare brain areas for target enhancement. Here, we consider two alternative mechanisms: secondary inhibition and expectation suppression within a predictive coding framework. We draw on behavioural studies, evidence from neuroimaging and some animal studies. We conclude that there is very limited evidence for selective top-down control of preparatory inhibition. By contrast, we argue that distractor suppression often relies secondary inhibition of non-target items (relatively non-selective inhibition) and on statistical regularities of the environment, learned through direct experience. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Human β-defensin 3-combined gold nanoparticles for enhancement of osteogenic differentiation of human periodontal ligament cells in inflammatory microenvironments

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Zhou J

2018-01-01

Full Text Available Jing Zhou,1 Yangheng Zhang,1 Lingjun Li,1 Huangmei Fu,2 Wenrong Yang,2 Fuhua Yan1 1Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, People’s Republic of China; 2School of Life and Environmental Science, Centre for Chemistry and Biotechnology, Deakin University, Geelong, VIC, Australia Objective: It is a great challenge to absorb and conduct biophysicochemical interactions at the nano-bio interface. Peptides are emerging as versatile materials whose function can be programmed to perform specific tasks. Peptides combined nanoparticles might be utilized as a new approach of treatment. Human β-defensin 3 (hBD3, possesses both antimicrobial and proregeneration properties. Gold nanoparticles (AuNPs have shown promising applications in the field of tissue engineering. However, the coordinating effects of AuNPs and hBD3 on human periodontal ligament cells (hPDLCs remain unknown. In this study, we systematically investigated whether AuNPs and hBD3 would be able to coordinate and enhance the osteogenic differentiation of hPDLCs in inflammatory microenvironments, and the underlying mechanisms was explored. Methods: hPDLCs were stimulated with E. coli-LPS, hBD3 and AuNPs. Alkaline phosphatase (ALP and alizarin red S staining were used to observe the effects of hBD3 and AuNPs on the osteogenic differentiation of hPDLCs. Real-time PCR and western blot were performed to evaluate the osteogenic differentiation and Wnt/β-catenin signaling pathway related gene and protein expression.Results: In the inflammatory microenvironments stimulated by E. coli-LPS, we found that AuNPs and hBD3 increased the proliferation of hPDLCs slightly. In addition, hBD3-combined AuNPs could significantly enhance ALP activities and mineral deposition in vitro. Meanwhile, we observed that the osteogenic differentiation-related gene and protein expressions of ALP, collagenase-I (COL-1 and runt-related transcription factor 2 (Runx-2 were

Inhibition by acrolein of light-induced stomatal opening through inhibition of inward-rectifying potassium channels in Arabidopsis thaliana.

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Islam, Md Moshiul; Ye, Wenxiu; Matsushima, Daiki; Khokon, Md Atiqur Rahman; Munemasa, Shintaro; Nakamura, Yoshimasa; Murata, Yoshiyuki

2015-01-01

Acrolein is a reactive α,β-unsaturated aldehyde derived from lipid peroxides, which are produced in plants under a variety of stress. We investigated effects of acrolein on light-induced stomatal opening using Arabidopsis thaliana. Acrolein inhibited light-induced stomatal opening in a dose-dependent manner. Acrolein at 100 μM inhibited plasma membrane inward-rectifying potassium (Kin) channels in guard cells. Acrolein at 100 μM inhibited Kin channel KAT1 expressed in a heterologous system using Xenopus leaves oocytes. These results suggest that acrolein inhibits light-induced stomatal opening through inhibition of Kin channels in guard cells.

Gliclazide directly inhibits arginine-induced glucagon release

DEFF Research Database (Denmark)

Cejvan, Kenan; Coy, David H; Holst, Jens Juul

2002-01-01

Arginine-stimulated insulin and somatostatin release is enhanced by the sulfonylurea gliclazide. In contrast, gliclazide inhibits the glucagon response. The aim of the present study was to investigate whether this inhibition of glucagon release was mediated by a direct suppressive effect of glicl......Arginine-stimulated insulin and somatostatin release is enhanced by the sulfonylurea gliclazide. In contrast, gliclazide inhibits the glucagon response. The aim of the present study was to investigate whether this inhibition of glucagon release was mediated by a direct suppressive effect....... In islet perifusions with DC-41-33, arginine-induced glucagon release was inhibited by 66%. We therefore concluded that gliclazide inhibits glucagon release by a direct action on the pancreatic A cell....

Kinetic investigation of uranyl-uranophile complexation. 1. Macrocyclic kinetic effect and macrocyclic protection effect

International Nuclear Information System (INIS)

Tabushi, I.; Yoshizawa, A.

1986-01-01

Equilibria and rates of ligand-exchange reactions between uranyl tricarbonate and dithiocarbamates and between uranyl tris-(dithiocarbamates) and carbonate were studied under a variety of conditions. The dithiocarbamates used were acyclic diethyl-dithiocarbamate and macrocyclic tris(dithiocarbamate). The acyclic ligand showed a triphasic (successive three-step) equilibrium with three different equilibrium constants while the macrocyclic ligand showed a clear monophasic (one-step) equilibrium with a much larger stability constant for the dithiocarbamate-uranyl complex. The macrocyclic ligand showed the S/sub N/2-type ligand-exchange rate in the forward as well as reverse process, while the first step of the acyclic ligand-exchange reaction proceeded via the S/sub N/1-type mechanism. This kinetic macrocyclic effect on molecularity is interpreted as the result of a unique topological requirement of uranyl complexation. The macrocyclic ligand also exhibited a clear protection effect, leading to the large stability constant. 19 references, 10 figures, 2 tables

Control of CA3 output by feedforward inhibition despite developmental changes in the excitation-inhibition balance.

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Torborg, Christine L; Nakashiba, Toshiaki; Tonegawa, Susumu; McBain, Chris J

2010-11-17

In somatosensory cortex, the relative balance of excitation and inhibition determines how effectively feedforward inhibition enforces the temporal fidelity of action potentials. Within the CA3 region of the hippocampus, glutamatergic mossy fiber (MF) synapses onto CA3 pyramidal cells (PCs) provide strong monosynaptic excitation that exhibit prominent facilitation during repetitive activity. We demonstrate in the juvenile CA3 that MF-driven polysynaptic IPSCs facilitate to maintain a fixed EPSC-IPSC ratio during short-term plasticity. In contrast, in young adult mice this MF-driven polysynaptic inhibitory input can facilitate or depress in response to short trains of activity. Transgenic mice lacking the feedback inhibitory loop continue to exhibit both facilitating and depressing polysynaptic IPSCs, indicating that this robust inhibition is not caused by the secondary engagement of feedback inhibition. Surprisingly, eliminating MF-driven inhibition onto CA3 pyramidal cells by blockade of GABA(A) receptors did not lead to a loss of temporal precision of the first action potential observed after a stimulus but triggered in many cases a long excitatory plateau potential capable of triggering repetitive action potential firing. These observations indicate that, unlike other regions of the brain, the temporal precision of single MF-driven action potentials is dictated primarily by the kinetics of MF EPSPs, not feedforward inhibition. Instead, feedforward inhibition provides a robust regulation of CA3 PC excitability across development to prevent excessive depolarization by the monosynaptic EPSP and multiple action potential firings.

A fusion-inhibiting peptide against Rift Valley fever virus inhibits multiple, diverse viruses.

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Jeffrey W Koehler

Full Text Available For enveloped viruses, fusion of the viral envelope with a cellular membrane is critical for a productive infection to occur. This fusion process is mediated by at least three classes of fusion proteins (Class I, II, and III based on the protein sequence and structure. For Rift Valley fever virus (RVFV, the glycoprotein Gc (Class II fusion protein mediates this fusion event following entry into the endocytic pathway, allowing the viral genome access to the cell cytoplasm. Here, we show that peptides analogous to the RVFV Gc stem region inhibited RVFV infectivity in cell culture by inhibiting the fusion process. Further, we show that infectivity can be inhibited for diverse, unrelated RNA viruses that have Class I (Ebola virus, Class II (Andes virus, or Class III (vesicular stomatitis virus fusion proteins using this single peptide. Our findings are consistent with an inhibition mechanism similar to that proposed for stem peptide fusion inhibitors of dengue virus in which the RVFV inhibitory peptide first binds to both the virion and cell membranes, allowing it to traffic with the virus into the endocytic pathway. Upon acidification and rearrangement of Gc, the peptide is then able to specifically bind to Gc and prevent fusion of the viral and endocytic membranes, thus inhibiting viral infection. These results could provide novel insights into conserved features among the three classes of viral fusion proteins and offer direction for the future development of broadly active fusion inhibitors.

Irreversible inhibition of RANK expression as a possible mechanism for IL-3 inhibition of RANKL-induced osteoclastogenesis

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Khapli, Shruti M.; Tomar, Geetanjali B.; Barhanpurkar, Amruta P.; Gupta, Navita; Yogesha, S.D.; Pote, Satish T. [National Center for Cell Science, University of Pune Campus, Pune 411 007 (India); Wani, Mohan R., E-mail: mohanwani@nccs.res.in [National Center for Cell Science, University of Pune Campus, Pune 411 007 (India)

2010-09-03

Research highlights: {yields} IL-3 inhibits receptor activator of NF-{kappa}B ligand (RANKL)-induced osteoclastogenesis. {yields} IL-3 inhibits RANKL-induced JNK activation. {yields} IL-3 down-regulates expression of c-Fos and NFATc1 transcription factors. {yields} IL-3 down-regulates RANK expression posttranscriptionally and irreversibly. {yields} IL-3 inhibits in vivo RANK expression. -- Abstract: IL-3, a cytokine secreted by activated T lymphocytes, stimulates the proliferation, differentiation and survival of pluripotent hematopoietic stem cells. In this study, we investigated the mechanism of inhibitory action of IL-3 on osteoclast differentiation. We show here that IL-3 significantly inhibits receptor activator of NF-{kappa}B (RANK) ligand (RANKL)-induced activation of c-Jun N-terminal kinase (JNK). IL-3 down-regulates expression of c-Fos and nuclear factor of activated T cells (NFATc1) transcription factors. In addition, IL-3 down-regulates RANK expression posttranscriptionally in both purified osteoclast precursors and whole bone marrow cells. Furthermore, the inhibitory effect of IL-3 on RANK expression was irreversible. Interestingly, IL-3 inhibits in vivo RANK expression in mice. Thus, we provide the first evidence that IL-3 irreversibly inhibits RANK expression that results in inhibition of important signaling molecules induced by RANKL.

Irreversible inhibition of RANK expression as a possible mechanism for IL-3 inhibition of RANKL-induced osteoclastogenesis

International Nuclear Information System (INIS)

Khapli, Shruti M.; Tomar, Geetanjali B.; Barhanpurkar, Amruta P.; Gupta, Navita; Yogesha, S.D.; Pote, Satish T.; Wani, Mohan R.

2010-01-01

Research highlights: → IL-3 inhibits receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis. → IL-3 inhibits RANKL-induced JNK activation. → IL-3 down-regulates expression of c-Fos and NFATc1 transcription factors. → IL-3 down-regulates RANK expression posttranscriptionally and irreversibly. → IL-3 inhibits in vivo RANK expression. -- Abstract: IL-3, a cytokine secreted by activated T lymphocytes, stimulates the proliferation, differentiation and survival of pluripotent hematopoietic stem cells. In this study, we investigated the mechanism of inhibitory action of IL-3 on osteoclast differentiation. We show here that IL-3 significantly inhibits receptor activator of NF-κB (RANK) ligand (RANKL)-induced activation of c-Jun N-terminal kinase (JNK). IL-3 down-regulates expression of c-Fos and nuclear factor of activated T cells (NFATc1) transcription factors. In addition, IL-3 down-regulates RANK expression posttranscriptionally in both purified osteoclast precursors and whole bone marrow cells. Furthermore, the inhibitory effect of IL-3 on RANK expression was irreversible. Interestingly, IL-3 inhibits in vivo RANK expression in mice. Thus, we provide the first evidence that IL-3 irreversibly inhibits RANK expression that results in inhibition of important signaling molecules induced by RANKL.

Human milk glycoconjugates that inhibit pathogens.

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Newburg, D S

1999-02-01

Breast-fed infants have lower incidence of diarrhea, respiratory disease, and otitis media. The protection by human milk has long been attributed to the presence of secretory IgA. However, human milk contains large numbers and amounts of complex carbohydrates, including glycoproteins, glycolipids, glycosaminoglycans, mucins, and especially oligosaccharides. The oligosaccharides comprise the third most abundant solid constituent of human milk, and contain a myriad of structures. Complex carbohydrate moieties of glycoconjugates and oligosaccharides are synthesized by the many glycosyltransferases in the mammary gland; those with homology to cell surface glycoconjugate pathogen receptors may inhibit pathogen binding, thereby protecting the nursing infant. Several examples are reviewed: A fucosyloligosaccharide inhibits the diarrheagenic effect of stable toxin of Escherichia coli. A different fucosyloligosaccharide inhibits infection by Campylobacter jejuni. Binding of Streptococcus pneumoniae and of enteropathogenic E. coli to their respective receptors is inhibited by human milk oligosaccharides. The 46-kD glycoprotein, lactadherin, inhibits rotavirus binding and infectivity. Low levels of lactadherin in human milk are associated with a higher incidence of symptomatic rotavirus in breast-fed infants. A mannosylated glycopeptide inhibits binding by enterohemorrhagic E. coli. A glycosaminoglycan inhibits binding of gp120 to CD4, the first step in HIV infection. Human milk mucin inhibits binding by S-fimbriated E. coli. The ganglioside, GM1, reduces diarrhea production by cholera toxin and labile toxin of E. coli. The neutral glycosphingolipid, Gb3, binds to Shigatoxin. Thus, many complex carbohydrates of human milk may be novel antipathogenic agents, and the milk glycoconjugates and oligosaccharides may be a major source of protection for breastfeeding infants.

Modeling intentional inhibition of actions

NARCIS (Netherlands)

Thilakarathne, D.J.; Treur, J.

2015-01-01

Inspired by cognitive and neurological literature on action ownership and action awareness, in this paper a computational cognitive model for intentional inhibition (i.e.; the capacity to voluntarily suspend or inhibit an action) is introduced. The interplay between (positive) potential selection of

Inhibition of ethylene production by cobaltous ion

International Nuclear Information System (INIS)

Lau, O.L; Yang, S.F.

1976-01-01

The effect of Co 2+ on ethylene production by mung bean (Phaseolus aureus Roxb.) and by apple tissues was studied. Co 2+ , depending on concentrations applied, effectively inhibited ethylene production by both tissues. It also strongly inhibited the ethylene production induced by IAA, kinetin, IAA plus kinetin, Ca 2+ , kinetin plus Ca 2+ , or Cu 2+ treatments in mung bean hypocotyl segments. While Co 2+ greatly inhibited ethylene production, it had little effect on the respiration of apple tissue, indicating that Co 2+ does not exert its inhibitory effect as a general metabolic inhibitor. Ni 2+ , which belongs to the same group as Co 2+ in the periodic table, also markedly curtailed both the basal and the induced ethylene production by apple and mung bean hypocotyl tissues. In a system in which kinetin and Ca 2+ were applied together, kinetin greatly enhanced Ca 2+ uptake, thus enhancing ethylene production. Co 2+ , however, slightly inhibited the uptake of Ca 2+ but appreciably inhibited ethylene production, either in the presence or in the absence of kinetin. Tracer experiments using apple tissue indicated that Co 2+ strongly inhibited the in vivo conversion of L-[U-- 14 C]methionine to 14 C-ethylene. These data suggested that Co 2+ inhibited ethylene production by inhibiting the conversion of methionine to ethylene, a common step which is required for ethylene formation by higher plants. Co 2+ is known to promote elongation, leaf expansion, and hook opening in excised plant parts in response to applied auxins or cytokinins.Since ethylene is known to inhibit those growth phenomena, it is suggested that Co 2+ exerts its promotive effect, at least in part, by inhibiting ethylene formation

Calcitriol-modulated human antibiotics: New pathophysiological aspects of vitamin D.

Science.gov (United States)

Amado Diago, Carlos Antonio; García-Unzueta, María Teresa; Fariñas, María del Carmen; Amado, Jose Antonio

2016-02-01

Traditionally, calcitriol has been considered a calcium and phosphate regulating hormone, but has recently been shown to play a pivotal role in innate immunity. Many barrier and immune cells have membrane and intracellular receptors that recognize different microbial antigens. Activation of these receptors induces synthesis of 1α-hydroxylase, which acts on 25 hydroxyvitamin D to generate intracellular calcitriol. Calcitriol activates its receptor and enhances the synthesis of important human antibiotics like cathelicidin and β2-defensin while inhibiting hepcidin. These pluripotent peptides have an important role in innate immunity, and their regulation is abnormal in hypovitaminosis D. The literature on their secretion mechanisms, levels in different organic fluids, mechanism of action, and relationship with vitamin D is reviewed here. Copyright © 2015 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

Inhibition Performance in Children with Math Disabilities

OpenAIRE

Winegar, Kathryn Lileth

2013-01-01

This study examined the inhibition deficit hypothesis in children with math disabilities (MD). Children with and without MD were compared on two inhibition tasks that included the random generation of numbers and letters. The results addressed three hypotheses. Weak support was found for the first hypothesis which stated difficulties related to inhibition are significantly related to math performance. I found partial support for this hypothesis in that inhibition was related to math problem s...

Characterization of acetylcholinesterase-inhibition by itopride.

Science.gov (United States)

Iwanaga, Y; Kimura, T; Miyashita, N; Morikawa, K; Nagata, O; Itoh, Z; Kondo, Y

1994-11-01

Itopride is a gastroprokinetic benzamide derivative. This agent inhibited both electric eel acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BuChE). The IC50 of itopride with AChE (2.04 +/- 0.27 microM) was, however, 100-fold less than that with BuChE, whereas in the case of neostigmine with AChE (11.3 +/- 3.4 nM), it was 10-fold less. The recovery of AChE activity inhibited by 10(-7) M neostigmine was partial, but that inhibited by up to 3 x 10(-5) M itopride was complete when the reaction mixture was subjected to ultrafiltration. Double reciprocal plots of the experimental data showed that both Km and Vmax were affected by itopride, suggesting that the inhibition is a "mixed" type, although primarily being an uncompetitive one. The inhibitory effect of itopride on cholinesterase (ChE) activity in guinea pig gastrointestine was much weaker than that on pure AChE. However, in the presence of a low dose of diisopropyl fluorophosphate, just enough to inhibit BuChE but not AChE, the IC50s of itopride against ChE activities were found to be about 0.5 microM. In conclusion, itopride exerts reversible and a "mixed" type of inhibition preferably against AChE. The IC50 of itopride for electric eel and guinea pig gastrointestinal AChE inhibition was 200 times and 50 times as large as that of neostigmine, respectively.

Kindergarteners' self-reported social inhibition and observed social reticence: moderation by adult-reported social inhibition and social anxiety disorder symptoms.

Science.gov (United States)

Kiel, Elizabeth J; Buss, Kristin A; Molitor, Joseph G

2015-04-01

Prevention of later anxiety problems would best be accomplished by identifying at-risk children early in development. For example, children who develop Social Anxiety Disorder (SAD) may show social withdrawal in the form of social inhibition (i.e., shyness with unfamiliar adults and peers) at school entry. Although the use of children's perceptions of their own social inhibition would provide insight into early risk, the utility of young children's self-reports remains unclear. The current study examined whether children deemed more extreme on social inhibition or social anxiety by adult report provided self-report of social inhibition that related to observed social reticence in the laboratory. Participants included 85 kindergarten children (36 female, 49 male), their parents, and their teachers. Moderation analyses revealed that children's self-reported social inhibition related significantly to observed social reticence under the conditions of high parent-reported social inhibition, high teacher-reported social inhibition, and high SAD symptoms. These results suggest that the most inhibited children are aware of their behavior and can report it in a meaningfully way as young as kindergarten age.

Dicumarol inhibition of NADPH:quinone oxidoreductase induces growth inhibition of pancreatic cancer via a superoxide-mediated mechanism.

Science.gov (United States)

Cullen, Joseph J; Hinkhouse, Marilyn M; Grady, Matthew; Gaut, Andrew W; Liu, Jingru; Zhang, Yu Ping; Weydert, Christine J Darby; Domann, Frederick E; Oberley, Larry W

2003-09-01

NADPH:quinone oxidoreductase (NQO(1)), a homodimeric, ubiquitous, flavoprotein, catalyzes the two-electron reduction of quinones to hydroquinones. This reaction prevents the one-electron reduction of quinones by cytochrome P450 reductase and other flavoproteins that would result in oxidative cycling with generation of superoxide (O(2)(.-)). NQO(1) gene regulation may be up-regulated in some tumors to accommodate the needs of rapidly metabolizing cells to regenerate NAD(+). We hypothesized that pancreatic cancer cells would exhibit high levels of this enzyme, and inhibiting it would suppress the malignant phenotype. Reverse transcription-PCR, Western blots, and activity assays demonstrated that NQO(1) was up-regulated in the pancreatic cancer cell lines tested but present in very low amounts in the normal human pancreas. To determine whether inhibition of NQO(1) would alter the malignant phenotype, MIA PaCa-2 pancreatic cancer cells were treated with a selective inhibitor of NQO(1), dicumarol. Dicumarol increased intracellular production of O(2)(.-), as measured by hydroethidine staining, and inhibited cell growth. Both of these effects were blunted with infection of an adenoviral vector containing the cDNA for manganese superoxide dismutase. Dicumarol also inhibited cell growth, plating efficiency, and growth in soft agar. We conclude that inhibition of NQO(1) increases intracellular O(2)(.-) production and inhibits the in vitro malignant phenotype of pancreatic cancer. These mechanisms suggest that altering the intracellular redox environment of pancreatic cancer cells may inhibit growth and delineate a potential strategy directed against pancreatic cancer.

Inhibiting prenylation augments chemotherapy efficacy in renal cell carcinoma through dual inhibition on mitochondrial respiration and glycolysis.

Science.gov (United States)

Huang, Jiangrong; Yang, Xiaoyu; Peng, Xiaochun; Huang, Wei

2017-11-18

Prenylation is a posttranslational lipid modification required for the proper functions of a number of proteins involved in cell regulation. Here, we show that prenylation inhibition is important for renal cell carcinoma (RCC) growth, survival and response to chemotherapy, and its underlying mechanism may be contributed to mitochondrial dysfunction. We first demonstrated that a HMG-CoA reductase inhibitor pitavastatin inhibited mevalonate pathway and thereby prenylation in RCC cells. In addition, pitavastatin is effective in inhibiting growth and inducing apoptosis in a panel of RCC cell lines. Combination of pitavastatin and paclitaxel is significantly more effective than pitavastatin or paclitaxel alone as shown by both in vitro cell culture system and in vivo RCC xenograft model. Importantly, pitavastatin treatment inhibits mitochondrial respiration via suppressing mitochondrial complex I and II enzyme activities. Interestingly, different from mitochondrial inhibitor phenformin that inhibits mitochondrial respiration but activates glycolytic rate in RCC cells, pitavastatin significantly decreases glycolytic rate. The dual inhibitory action of pitavastatin on mitochondrial respiration and glycolysis results in remarkable energy depletion and oxidative stress in RCC cells. In addition, inhibition of prenylation by depleting Isoprenylcysteine carboxylmethyltransferase (Icmt) also mimics the inhibitory effects of pitavastatin in RCC cells. Our work demonstrates the previously unappreciated association between prenylation inhibition and energy metabolism in RCC, which can be therapeutically exploited, likely in tumors that largely rely on energy metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

On the problem of finding disjoint cycles and dicycles in a digraph

DEFF Research Database (Denmark)

Bang-Jensen, Jørgen; Kriesell, M.

2011-01-01

.e. the smallest cardinality of a set T of vertices in D such that D-T is acyclic: If tau (D)a parts per thousand yen3 then we employ McCuaig's framework on intercyclic digraphs to (always) find these cycles. If tau (D) = 2 then we can characterize the digraphs for which the answer is "yes" by using topological...... methods relying on Thomassen's theorem on 2-linkages in acyclic digraphs. For the case tau (D)a parts per thousand currency sign1 we provide an algorithm independent from any earlier work....

Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis II. Quantification of inhibition and suitability of membrane reactors

DEFF Research Database (Denmark)

Andric, Pavle; Meyer, Anne S.; Jensen, Peter Arendt

2010-01-01

conversion are required for alleviation of glucose product inhibition. Supported by numerous calculations this review assesses the quantitative aspects of glucose product inhibition on enzyme-catalyzed cellulose degradation rates. The significance of glucose product inhibition on dimensioning of different......Product inhibition of cellulolytic enzymes affects the efficiency of the biocatalytic conversion of lignocellulosic biomass to ethanol and other valuable products. New strategies that focus on reactor designs encompassing product removal, notably glucose removal, during enzymatic cellulose...... reactor features, including system set-up, dilution rate, glucose output profile, and the problem of cellobiose are examined to illustrate the quantitative significance of the glucose product inhibition and the total glucose concentration on the cellulolytic conversion rate. Comprehensive overviews...

Kindergarteners’ Self-Reported Social Inhibition and Observed Social Reticence: Moderation by Adult-Reported Social Inhibition and Social Anxiety Disorder Symptoms

Science.gov (United States)

Kiel, Elizabeth J.; Buss, Kristin A.; Molitor, Joseph G.

2014-01-01

Prevention of later anxiety problems would best be accomplished by identifying at-risk children early in development. For example, children who develop Social Anxiety Disorder (SAD) may show social withdrawal in the form of social inhibition (i.e., shyness with unfamiliar adults and peers) at school entry. Although the use of children’s perceptions of their own social inhibition would provide insight into early risk, the utility of young children’s self-reports remains unclear. The current study examined whether children deemed more extreme on social inhibition or social anxiety by adult report provided self-report of social inhibition that related to observed social reticence in the laboratory. Participants included 85 kindergarten children (36 female, 49 male), their parents, and their teachers. Moderation analyses revealed that children’s self-reported social inhibition related significantly to observed social reticence under the conditions of high parent-reported social inhibition, high teacher-reported social inhibition, and high SAD symptoms. These results suggest that the most inhibited children are aware of their behavior and can report it in a meaningfully way as young as kindergarten age. PMID:25113397

Differential effects of metal contamination on the transcript expression of immune- and stress-response genes in the Sydney Rock oyster, Saccostrea glomerata

International Nuclear Information System (INIS)

Taylor, Daisy A.; Thompson, Emma L.; Nair, Sham V.; Raftos, David A.

2013-01-01

Environmental contamination by metals is a serious threat to the biological sustainability of coastal ecosystems. Our current understanding of the potential biological effects of metals in these ecosystems is limited. This study tested the transcriptional expression of immune- and stress-response genes in Sydney Rock oysters (Saccostrea glomerata). Oysters were exposed to four metals (cadmium, copper, lead and zinc) commonly associated with anthropogenic pollution in coastal waterways. Seven target genes (superoxide dismutase, ferritin, ficolin, defensin, HSP70, HSP90 and metallothionein) were selected. Quantitative (real-time) PCR analyses of the transcript expression of these genes showed that each of the different metals elicited unique transcriptional profiles. Significant changes in transcription were found for 18 of the 28 combinations tested (4 metals × 7 genes). Of these, 16 reflected down-regulation of gene transcription. HSP90 was the only gene significantly up-regulated by metal contamination (cadmium and zinc only), while defensin expression was significantly down-regulated by exposure to all four metals. This inhibition could have a significant negative effect on the oyster immune system, promoting susceptibility to opportunistic infections and disease. -- Highlights: ► Oysters were exposed to Cd, Cu, Pb or Zn, all commonly associated with coastal pollution. ► qPCR identified significant down-regulation in stress- and immune-response genes in oysters exposed to these metals. ► qPCR showed that each of the different metals elicited unique transcriptional profiles. ► The genes identified have the potential to lead to increased disease susceptibility in oysters. -- qPCR identified significant down-regulation in stress- and immune-response genes in oysters exposed to metals, which could lead to increased disease susceptibility

D-Glucosamine inhibits proliferation of human cancer cells through inhibition of p70S6K

International Nuclear Information System (INIS)

Oh, Hyun-Ji; Lee, Jason S.; Song, Dae-Kyu; Shin, Dong-Hoon; Jang, Byeong-Churl; Suh, Seong-Il; Park, Jong-Wook; Suh, Min-Ho; Baek, Won-Ki

2007-01-01

Although D-glucosamine has been reported as an inhibitor of tumor growth both in vivo and in vitro, the mechanism for the anticancer effect of D-glucosamine is still unclear. Since there are several reports suggesting D-glucosamine inhibits protein synthesis, we examined whether D-glucosamine affects p70S6 K activity, an important signaling molecule involved in protein translation. In the present study, we found D-glucosamine inhibited the activity of p70S6K and the proliferation of DU145 prostate cancer cells and MDA-MB-231 breast cancer cells. D-Glucosamine decreased phosphorylation of p70S6K, and its downstream substrates RPS6, and eIF-4B, but not mTOR and 4EBP1 in DU145 cells, suggesting that D-glucosamine induced inhibition of p70S6K is not through the inhibition of mTOR. In addition, D-glucosamine enhanced the growth inhibitory effects of rapamycin, a specific inhibitor of mTOR. These findings suggest that D-glucosamine can inhibit growth of cancer cells through dephosphorylation of p70S6K

Similarities between Reproductive and Immune Pistil Transcriptomes of Arabidopsis Species.

Science.gov (United States)

Mondragón-Palomino, Mariana; John-Arputharaj, Ajay; Pallmann, Maria; Dresselhaus, Thomas

2017-07-01

Independent lines of evidence suggest that members from ancient and polymorphic gene families such as defensins and receptor-like kinases mediate intercellular communication during both the immune response and reproduction. Here, we report a large-scale analysis to investigate the extent of overlap between these processes by comparing differentially expressed genes (DEGs) in the pistil transcriptomes of Arabidopsis thaliana and Arabidopsis halleri during self-pollination and interspecific pollination and during infection with Fusarium graminearum In both Arabidopsis species, the largest number of DEGs was identified in infected pistils, where genes encoding regulators of cell division and development were most frequently down-regulated. Comparison of DEGs between infection and various pollination conditions showed that up to 79% of down-regulated genes are shared between conditions and include especially defensin-like genes. Interspecific pollination of A. thaliana significantly up-regulated thionins and defensins. The significant overrepresentation of similar groups of DEGs in the transcriptomes of reproductive and immune responses of the pistil makes it a prime system in which to study the consequences of plant-pathogen interactions on fertility and the evolution of intercellular communication in pollination. © 2017 American Society of Plant Biologists. All Rights Reserved.

Can Arousal Modulate Response Inhibition?

Science.gov (United States)

Weinbach, Noam; Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai

2015-01-01

The goal of the present study was to examine if and how arousal can modulate response inhibition. Two competing hypotheses can be drawn from previous literature. One holds that alerting cues that elevate arousal should result in an impulsive response and therefore impair response inhibition. The other suggests that alerting enhances processing of…

Ketamine inhibits 45Ca influx and catecholamine secretion by inhibiting 22Na influx in cultured bovine adrenal medullary cells

International Nuclear Information System (INIS)

Takara, Hiroshi; Wada, Akihiko; Arita, Masahide; Izumi, Futoshi; Sumikawa, Koji

1986-01-01

The effects of ketamine, an intravenous anesthetic, on 22 Na influx, 45 Ca influx and catecholamine secretion were investigated in cultured bovine adrenal medullary cells. Ketamine inhibited carbachol-induced 45 Ca influx and catecholamine secretion in a concentration-dependent manner with a similar potency. Ketamine also reduced veratridine-induced 45 Ca influx and catecholamine secretion. The influx of 22 Na caused by carbachol or by veratridine was suppressed by ketamine with a concentration-inhibition curve similar to that of 45 Ca influx and catecholamine secretion. Inhibition by ketamine of the carbachol-induced influx of 22 Na, 45 Ca and secretion of catecholamines was not reversed by the increased concentrations of carbachol. These observations indicate that ketamine, at clinical concentrations, can inhibit nicotinic receptor-associated ionic channels and that the inhibition of Na influx via the receptor-associated ionic channels is responsible for the inhibition of carbachol-induced Ca influx and catecholamine secretion. (Auth.)

Terbinafine inhibits gap junctional intercellular communication

International Nuclear Information System (INIS)

Lee, Ju Yeun; Yoon, Sei Mee; Choi, Eun Ju; Lee, Jinu

2016-01-01

Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca 2+ concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. - Highlights: • In vitro pharmacological studies were performed on FRT-Cx43 and LN215 cells. • Terbinafine inhibits gap junctional intercellular communication in both cell lines. • The inhibitory effect of terbinafine is reversible and dose-dependent. • Treatment of terbinafine does not alter Cx43 phosphorylation or cytosolic Ca 2+ concentration. • Inhibition of squalene epoxidase is not involved in this new effect of terbinafine.

A speculated cause of respiratory inhibition in infants.

Science.gov (United States)

Minowa, Hideki; Arai, Ikuyo; Yasuhara, Hajime; Ebisu, Reiko; Ohgitani, Ayako

2018-10-01

In our previous studies, we documented that threatened premature labor and asymmetrical intrauterine growth restriction were risk factors for respiratory inhibition. The goal of this study was to determine the cause of respiratory inhibition by considering perinatal risk factors. We examined 1497 infants with a gestational age of 36 weeks or greater. All infants were monitored using pulse oximetry and examined via cranial sonography. Respiratory inhibition was defined as severe hypoxemia caused by respiratory inhibition immediately after crying or gastroesophageal reflux or as a respiratory pause during feeding. We examined the relationships between respiratory inhibition and perinatal factors and speculated on the cause of respiratory inhibition. The median gestational age, birth weight, Apgar score at 1 min, and Apgar score at 5 min of the subjects were 38.9 weeks, 2930 g, 8.0 points, and 9.0 points, respectively. Respiratory inhibition was observed in 422 infants. Lateral ventricle enlargement and increased echogenicity in the ganglionic eminence were observed in 417 and 516 infants, respectively. Respiratory inhibition was significantly correlated with shorter gestational periods, twin pregnancies, lateral ventricle enlargement, and increased echogenicity in the ganglionic eminence. We speculate that umbilical cord compression is a major cause of respiratory inhibition.

Inhibition in the Human Auditory Cortex.

Directory of Open Access Journals (Sweden)

Koji Inui

Full Text Available Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observed by inserting a weak (5 dB increase for 1 ms prepulse. The time course of the inhibition evaluated by prepulses presented at 10-800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20-60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful.

Pharmacologic inhibition of lactate production prevents myofibroblast differentiation.

Science.gov (United States)

Kottmann, Robert Matthew; Trawick, Emma; Judge, Jennifer L; Wahl, Lindsay A; Epa, Amali P; Owens, Kristina M; Thatcher, Thomas H; Phipps, Richard P; Sime, Patricia J

2015-12-01

Myofibroblasts are one of the primary cell types responsible for the accumulation of extracellular matrix in fibrosing diseases, and targeting myofibroblast differentiation is an important therapeutic strategy for the treatment of pulmonary fibrosis. Transforming growth factor-β (TGF-β) has been shown to be an important inducer of myofibroblast differentiation. We previously demonstrated that lactate dehydrogenase and its metabolic product lactic acid are important mediators of myofibroblast differentiation, via acid-induced activation of latent TGF-β. Here we explore whether pharmacologic inhibition of LDH activity can prevent TGF-β-induced myofibroblast differentiation. Primary human lung fibroblasts from healthy patients and those with pulmonary fibrosis were treated with TGF-β and or gossypol, an LDH inhibitor. Protein and RNA were analyzed for markers of myofibroblast differentiation and extracellular matrix generation. Gossypol inhibited TGF-β-induced expression of the myofibroblast marker α-smooth muscle actin (α-SMA) in a dose-dependent manner in both healthy and fibrotic human lung fibroblasts. Gossypol also inhibited expression of collagen 1, collagen 3, and fibronectin. Gossypol inhibited LDH activity, the generation of extracellular lactic acid, and the rate of extracellular acidification in a dose-dependent manner. Furthermore, gossypol inhibited TGF-β bioactivity in a dose-dependent manner. Concurrent treatment with an LDH siRNA increased the ability of gossypol to inhibit TGF-β-induced myofibroblast differentiation. Gossypol inhibits TGF-β-induced myofibroblast differentiation through inhibition of LDH, inhibition of extracellular accumulation of lactic acid, and inhibition of TGF-β bioactivity. These data support the hypothesis that pharmacologic inhibition of LDH may play an important role in the treatment of pulmonary fibrosis. Copyright © 2015 the American Physiological Society.

Atorvastatin inhibits insulin synthesis by inhibiting the Ras/Raf/ERK/CREB pathway in INS-1 cells

Science.gov (United States)

Sun, Hongxi; Li, Yu; Sun, Bei; Hou, Ningning; Yang, Juhong; Zheng, Miaoyan; Xu, Jie; Wang, Jingyu; Zhang, Yi; Zeng, Xianwei; Shan, Chunyan; Chang, Bai; Chen, Liming; Chang, Baocheng

2016-01-01

Abstract Backround: Type 2 diabetes has become a global epidemic disease. Atorvastatin has become a cornerstone in the prevention and treatment of atherosclerosis. However, increasing evidence showed that statins can dose-dependently increase the risk of diabetes mellitus. The mechanism is not clear. Objective: The Ras complex pathway (Ras/Raf/extracellular signal-regulated kinase [ERK]/cAMP response element-binding protein [CREB]) is the major pathway that regulates the gene transcription. Except for the inhibition of cholesterol synthesis by inhibiting the 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-COA) reductase, statins can also downregulate the phosphorylation of a series of downstream substrates including the key proteins of the Ras complex pathway, therefore may inhibit the insulin syntheses in pancreatic beta cells. In our study, we investigated the inhibitory effect and the underlying mechanism of atorvastatin on insulin synthesis in rat islets. Methods: Islets were isolated from Wistar rats and cultured in Roswell Park Memorial Institute (RPMI)-1640 medium. The insulin content in the medium was measured by radioimmunoassay before and after the treatment of 50 μM atorvastatin. Effect of atorvastatin on the expression of insulin message Ribonucleic acid (mRNA) in pancreatic islet beta cells was also detected using quantitative real-time polymerase chain reaction. Western blotting was used to explore the possible role of the Ras complex pathway (Ras/Raf/ERK/CREB) in atorvastatin-inhibited insulin synthesis. The effects of atorvastatin on the binding of nuclear transcription factor p-CREB with CRE in INS-1 cells were examined via chromatin immunoprecipitation assay. Results: Compared with the control group, the insulin level decreased by 27.1% at 24 hours after atorvastatin treatment. Atorvastatin inhibited insulin synthesis by decreasing insulin mRNA expression of pancreatic islet beta cells. The activities of Ras, Raf-1, and p-CREB in the Ras complex

Inhibiting cancer cell hallmark features through nuclear export inhibition.

Science.gov (United States)

Sun, Qingxiang; Chen, Xueqin; Zhou, Qiao; Burstein, Ezra; Yang, Shengyong; Jia, Da

2016-01-01

Treating cancer through inhibition of nuclear export is one of the best examples of basic research translation into clinical application. Nuclear export factor chromosomal region maintenance 1 (CRM1; Xpo1 and exportin-1) controls cellular localization and function of numerous proteins that are critical for the development of many cancer hallmarks. The diverse actions of CRM1 are likely to explain the broad ranging anti-cancer potency of CRM1 inhibitors observed in pre-clinical studies and/or clinical trials (phase I-III) on both advanced-stage solid and hematological tumors. In this review, we compare and contrast the mechanisms of action of different CRM1 inhibitors, and discuss the potential benefit of unexplored non-covalent CRM1 inhibitors. This emerging field has uncovered that nuclear export inhibition is well poised as an attractive target towards low-toxicity broad-spectrum potent anti-cancer therapy.

Hypnotic suggestibility, cognitive inhibition, and dissociation.

Science.gov (United States)

Dienes, Zoltán; Brown, Elizabeth; Hutton, Sam; Kirsch, Irving; Mazzoni, Giuliana; Wright, Daniel B

2009-12-01

We examined two potential correlates of hypnotic suggestibility: dissociation and cognitive inhibition. Dissociation is the foundation of two of the major theories of hypnosis and other theories commonly postulate that hypnotic responding is a result of attentional abilities (including inhibition). Participants were administered the Waterloo-Stanford Group Scale of Hypnotic Susceptibility, Form C. Under the guise of an unrelated study, 180 of these participants also completed: a version of the Dissociative Experiences Scale that is normally distributed in non-clinical populations; a latent inhibition task, a spatial negative priming task, and a memory task designed to measure negative priming. The data ruled out even moderate correlations between hypnotic suggestibility and all the measures of dissociation and cognitive inhibition overall, though they also indicated gender differences. The results are a challenge for existing theories of hypnosis.

Processing, disulfide pattern, and biological activity of a sugar beet defensin, AX2, expressed in Pichia pastoris

DEFF Research Database (Denmark)

Kristensen, A K; Brunstedt, J; Nielsen, J E

1999-01-01

AX2 is a 46-amino-acid cysteine-rich peptide isolated from sugar beet leaves infected with the fungus Cercospora beticola (Sacc.). AX2 strongly inhibits the growth of C. beticola and other filamentous fungi, but has little or no effect against bacteria. AX2 is produced in very low amounts in suga...

Inhibition of lignin-derived phenolic compounds to cellulase.

Science.gov (United States)

Qin, Lei; Li, Wen-Chao; Liu, Li; Zhu, Jia-Qing; Li, Xia; Li, Bing-Zhi; Yuan, Ying-Jin

2016-01-01

Lignin-derived phenolic compounds are universal in the hydrolysate of pretreated lignocellulosic biomass. The phenolics reduce the efficiency of enzymatic hydrolysis and increase the cost of ethanol production. We investigated inhibition of phenolics on cellulase during enzymatic hydrolysis using vanillin as one of the typical lignin-derived phenolics and Avicel as cellulose substrate. As vanillin concentration increased from 0 to 10 mg/mL, cellulose conversion after 72-h enzymatic hydrolysis decreased from 53 to 26 %. Enzyme deactivation and precipitation were detected with the vanillin addition. The enzyme concentration and activity consecutively decreased during hydrolysis, but the inhibition degree, expressed as the ratio of the cellulose conversion without vanillin to the conversion with vanillin (A 0 /A), was almost independent on hydrolysis time. Inhibition can be mitigated by increasing cellulose loading or cellulase concentration. The inhibition degree showed linear relationship with the vanillin concentration and exponential relationship with the cellulose loading and the cellulase concentration. The addition of calcium chloride, BSA, and Tween 80 did not release the inhibition of vanillin significantly. pH and temperature for hydrolysis also showed no significant impact on inhibition degree. The presence of hydroxyl group, carbonyl group, and methoxy group in phenolics affected the inhibition degree. Besides phenolics concentration, other factors such as cellulose loading, enzyme concentration, and phenolic structure also affect the inhibition of cellulose conversion. Lignin-blocking agents have little effect on the inhibition effect of soluble phenolics, indicating that the inhibition mechanism of phenolics to enzyme is likely different from insoluble lignin. The inhibition of soluble phenolics can hardly be entirely removed by increasing enzyme concentration or adding blocking proteins due to the dispersity and multiple binding sites of phenolics

Altered cortical processing of motor inhibition in schizophrenia.

Science.gov (United States)

Lindberg, Påvel G; Térémetz, Maxime; Charron, Sylvain; Kebir, Oussama; Saby, Agathe; Bendjemaa, Narjes; Lion, Stéphanie; Crépon, Benoît; Gaillard, Raphaël; Oppenheim, Catherine; Krebs, Marie-Odile; Amado, Isabelle

2016-12-01

Inhibition is considered a key mechanism in schizophrenia. Short-latency intracortical inhibition (SICI) in the motor cortex is reduced in schizophrenia and is considered to reflect locally deficient γ-aminobutyric acid (GABA)-ergic modulation. However, it remains unclear how SICI is modulated during motor inhibition and how it relates to neural processing in other cortical areas. Here we studied motor inhibition Stop signal task (SST) in stabilized patients with schizophrenia (N = 28), healthy siblings (N = 21) and healthy controls (n = 31) matched in general cognitive status and educational level. Transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) were used to investigate neural correlates of motor inhibition. SST performance was similar in patients and controls. SICI was modulated by the task as expected in healthy controls and siblings but was reduced in patients with schizophrenia during inhibition despite equivalent motor inhibition performance. fMRI showed greater prefrontal and premotor activation during motor inhibition in schizophrenia. Task-related modulation of SICI was higher in subjects who showed less inhibition-related activity in pre-supplementary motor area (SMA) and cingulate motor area. An exploratory genetic analysis of selected markers of inhibition (GABRB2, GAD1, GRM1, and GRM3) did not explain task-related differences in SICI or cortical activation. In conclusion, this multimodal study provides direct evidence of a task-related deficiency in SICI modulation in schizophrenia likely reflecting deficient GABA-A related processing in motor cortex. Compensatory activation of premotor areas may explain similar motor inhibition in patients despite local deficits in intracortical processing. Task-related modulation of SICI may serve as a useful non-invasive GABAergic marker in development of therapeutic strategies in schizophrenia. Copyright © 2016 Elsevier Ltd. All rights reserved.

A rhodanine derivative CCR-11 inhibits bacterial proliferation by inhibiting the assembly and GTPase activity of FtsZ.

Science.gov (United States)

Singh, Parminder; Jindal, Bhavya; Surolia, Avadhesha; Panda, Dulal

2012-07-10

A perturbation of FtsZ assembly dynamics has been shown to inhibit bacterial cytokinesis. In this study, the antibacterial activity of 151 rhodanine compounds was assayed using Bacillus subtilis cells. Of 151 compounds, eight strongly inhibited bacterial proliferation at 2 μM. Subsequently, we used the elongation of B. subtilis cells as a secondary screen to identify potential FtsZ-targeted antibacterial agents. We found that three compounds significantly increased bacterial cell length. One of the three compounds, namely, CCR-11 [(E)-2-thioxo-5-({[3-(trifluoromethyl)phenyl]furan-2-yl}methylene)thiazolidin-4-one], inhibited the assembly and GTPase activity of FtsZ in vitro. CCR-11 bound to FtsZ with a dissociation constant of 1.5 ± 0.3 μM. A docking analysis indicated that CCR-11 may bind to FtsZ in a cavity adjacent to the T7 loop and that short halogen-oxygen, H-bonding, and hydrophobic interactions might be important for the binding of CCR-11 with FtsZ. CCR-11 inhibited the proliferation of B. subtilis cells with a half-maximal inhibitory concentration (IC(50)) of 1.2 ± 0.2 μM and a minimal inhibitory concentration of 3 μM. It also potently inhibited proliferation of Mycobacterium smegmatis cells. Further, CCR-11 perturbed Z-ring formation in B. subtilis cells; however, it neither visibly affected nucleoid segregation nor altered the membrane integrity of the cells. CCR-11 inhibited HeLa cell proliferation with an IC(50) value of 18.1 ± 0.2 μM (∼15 × IC(50) of B. subtilis cell proliferation). The results suggested that CCR-11 inhibits bacterial cytokinesis by inhibiting FtsZ assembly, and it can be used as a lead molecule to develop FtsZ-targeted antibacterial agents.

Molecular mechanisms of DNA repair inhibition by caffeine

Energy Technology Data Exchange (ETDEWEB)

Selby, C.P.; Sancar, A. (Univ. of North Carolina School of Medicine, Chapel Hill (USA))

1990-05-01

Caffeine potentiates the mutagenic and lethal effects of genotoxic agents. It is thought that this is due, at least in some organisms, to inhibition of DNA repair. However, direct evidence for inhibition of repair enzymes has been lacking. Using purified Escherichia coli DNA photolyase and (A)BC excinuclease, we show that the drug inhibits photoreactivation and nucleotide excision repair by two different mechanisms. Caffeine inhibits photoreactivation by interfering with the specific binding of photolyase to damaged DNA, and it inhibits nucleotide excision repair by promoting nonspecific binding of the damage-recognition subunit, UvrA, of (A)BC excinuclease. A number of other intercalators, including acriflavin and ethidium bromide, appear to inhibit the excinuclease by a similar mechanism--that is, by trapping the UvrA subunit in nonproductive complexes on undamaged DNA.

Terbinafine inhibits gap junctional intercellular communication

Energy Technology Data Exchange (ETDEWEB)

Lee, Ju Yeun, E-mail: whitewndus@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Yoon, Sei Mee, E-mail: sei_mee@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Department of Integrated OMICS for Biomedical Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Choi, Eun Ju, E-mail: yureas@naver.com [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of); Lee, Jinu, E-mail: jinulee@yonsei.ac.kr [College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983 (Korea, Republic of)

2016-09-15

Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca{sup 2+} concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. - Highlights: • In vitro pharmacological studies were performed on FRT-Cx43 and LN215 cells. • Terbinafine inhibits gap junctional intercellular communication in both cell lines. • The inhibitory effect of terbinafine is reversible and dose-dependent. • Treatment of terbinafine does not alter Cx43 phosphorylation or cytosolic Ca{sup 2+} concentration. • Inhibition of squalene epoxidase is not involved in this new effect of terbinafine.

Uranyl(VI) and lanthanum(III) complexes with functionalized macrocyclic and macroacyclic Schiff bases

International Nuclear Information System (INIS)

Aguiari, A.; Brianese, N.; Tamburini, S.; Vigato, P.A.

1995-01-01

Acyclic Schiff bases have been prepared by [2 + 1] condensation of 2,6-diformyl-4-chlorophenol and H 2 NCH 2 [CH 2 XCH 2 ] n CH 2 NH 2 (n =3D 0 H 2 -I; X =3D NH, S, O n =3D 1 H 2 -II...H 2 -IV; X =3D 0 n =3D 2 H 2 -V; X =3D 0 n =3D 3 H 2 -VI). The related uranlyl(VI) and lanthanum (III) complexes have bee synthesized by reaction by reaction of the preformed ligands with the appropriate salt or by the template procedure, in the presence of base. No base was employed in the preparation of lanthanum (III) complexes, La(H 2 -II)(NO 3 ) 3 , La(H 2 -IV)(NO 3 ) 3 where the Schiff bases coordinate as neutral chelate ligands. These acyclic complexes have been used for further condensation, and symmetric and asymmetric cyclic complexes have been obtained by their reaction with the polyamines H 2 NCH 2 [CH 2 XCH 2 ]nCH 2 NH 2 or with 4,4'-diaminodibenzo -18-crown-6. By reaction with 4-aminobenzo-15-crown-5 or 2-amino-methyl-15-crown-5, the same acyclic complexes give rise to functionalized complexes bearing crown-ether moieties. Analogously, the acyclic ligand H 3 -IXX, prepared by condensation of 2,6 diformyl-4-chlorophenol and tris(aminoethyl)amine, forms mono and homodinuclear lanthanum (III) complexes, which may undergo further condensation when reacted with primary functionalized amines. (authors). 42 refs., 2 figs., 2 schemes, 1 tab

Incorporation of [1-C14] Isopentenyl Pyrophosphate into Carotenoids and Homo carotenoids using a Cell-free Preparation of Micrococcus Luteus

International Nuclear Information System (INIS)

Al-Wandawi, H.

1998-01-01

The early steps up to the formation of acyclic unsaturated carotenes (e.g.,phytoene to lycopene) are presumed to be common to the biosynthesis of all carotenoids with 40 or more carbon atoms, nevertheless, no direct evidence so far available to confirm this for homo carotenoids (c 45 and c 50 carotenoids). In the present study, an active cell-free preparation was obtained from diphenylamine-inhibited cells of Micrococcus Iuteus and found to be capable to incorporate radioactivity from Isopentenyl pyrophosphate (labelled with C-14)into carotenoids and homo carotenoids, providing for the first time a direct evidence which suggests that both carotenoids and homo carotenoids are sharing the same biological origin. Furthermore, the technique developed in this study may be considered as a valuable method for preparation of biological-active labelled compounds which may have some advantages over conventional chemical syntheses methods

Celastrol inhibits TGF-β1-induced epithelial–mesenchymal transition by inhibiting Snail and regulating E-cadherin expression

Energy Technology Data Exchange (ETDEWEB)

Kang, Hyereen; Lee, Minjae [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Jang, Sung-Wuk, E-mail: swjang@amc.seoul.kr [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of)

2013-08-09

Highlights: •We investigated the effects of celastrol on TGF-β1-induced EMT in epithelial cells. •Celastrol regulates TGF-β1-induced morphological changes and E-cadherin expression. •Celastrol inhibits TGF-β1-induced Snail expression. •Celastrol strongly suppresses TGF-β1-induced invasion in MDCK and A549 cells. -- Abstract: The epithelial–mesenchymal transition (EMT) is a pivotal event in the invasive and metastatic potentials of cancer progression. Celastrol inhibits the proliferation of a variety of tumor cells including leukemia, glioma, prostate, and breast cancer; however, the possible role of celastrol in the EMT is unclear. We investigated the effect of celastrol on the EMT. Transforming growth factor-beta 1 (TGF-β1) induced EMT-like morphologic changes and upregulation of Snail expression. The downregulation of E-cadherin expression and upregulation of Snail in Madin–Darby Canine Kidney (MDCK) and A549 cell lines show that TGF-β1-mediated the EMT in epithelial cells; however, celastrol markedly inhibited TGF-β1-induced morphologic changes, Snail upregulation, and E-cadherin expression. Migration and invasion assays revealed that celastrol completely inhibited TGF-β1-mediated cellular migration in both cell lines. These findings indicate that celastrol downregulates Snail expression, thereby inhibiting TGF-β1-induced EMT in MDCK and A549 cells. Thus, our findings provide new evidence that celastrol suppresses lung cancer invasion and migration by inhibiting TGF-β1-induced EMT.

Pseudomonas aeruginosa inhibits the growth of Cryptococcus species.

Science.gov (United States)

Rella, Antonella; Yang, Mo Wei; Gruber, Jordon; Montagna, Maria Teresa; Luberto, Chiara; Zhang, Yong-Mei; Del Poeta, Maurizio

2012-06-01

Pseudomonas aeruginosa is a ubiquitous and opportunistic bacterium that inhibits the growth of different microorganisms, including Gram-positive bacteria and fungi such as Candida spp. and Aspergillus fumigatus. In this study, we investigated the interaction between P. aeruginosa and Cryptococcus spp. We found that P. aeruginosa PA14 and, to a lesser extent, PAO1 significantly inhibited the growth of Cryptococcus spp. The inhibition of growth was observed on solid medium by the visualization of a zone of inhibition of yeast growth and in liquid culture by viable cell counting. Interestingly, such inhibition was only observed when P. aeruginosa and Cryptococcus were co-cultured. Minimal inhibition was observed when cell-cell contact was prevented using a separation membrane, suggesting that cell contact is required for inhibition. Using mutant strains of Pseudomonas quinoline signaling, we showed that P. aeruginosa inhibited the growth of Cryptococcus spp. by producing antifungal molecules pyocyanin, a redox-active phenazine, and 2-heptyl-3,4-dihydroxyquinoline (PQS), an extracellular quorum-sensing signal. Because both P. aeruginosa and Cryptococcus neoformans are commonly found in lung infections of immunocompromised patients, this study may have important implication for the interaction of these microbes in both an ecological and a clinical point of view.

Vitamin K3 (menadione) redox cycling inhibits cytochrome P450-mediated metabolism and inhibits parathion intoxication

Energy Technology Data Exchange (ETDEWEB)

Jan, Yi-Hua [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Richardson, Jason R., E-mail: jricha3@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Baker, Angela A. [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Mishin, Vladimir [Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Heck, Diane E. [Department of Environmental Health Science, New York Medical College, Valhalla, NY (United States); Laskin, Debra L. [Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States)

2015-10-01

Parathion, a widely used organophosphate insecticide, is considered a high priority chemical threat. Parathion toxicity is dependent on its metabolism by the cytochrome P450 system to paraoxon (diethyl 4-nitrophenyl phosphate), a cytotoxic metabolite. As an effective inhibitor of cholinesterases, paraoxon causes the accumulation of acetylcholine in synapses and overstimulation of nicotinic and muscarinic cholinergic receptors, leading to characteristic signs of organophosphate poisoning. Inhibition of parathion metabolism to paraoxon represents a potential approach to counter parathion toxicity. Herein, we demonstrate that menadione (methyl-1,4-naphthoquinone, vitamin K3) is a potent inhibitor of cytochrome P450-mediated metabolism of parathion. Menadione is active in redox cycling, a reaction mediated by NADPH-cytochrome P450 reductase that preferentially uses electrons from NADPH at the expense of their supply to the P450s. Using human recombinant CYP 1A2, 2B6, 3A4 and human liver microsomes, menadione was found to inhibit the formation of paraoxon from parathion. Administration of menadione bisulfite (40 mg/kg, ip) to rats also reduced parathion-induced inhibition of brain cholinesterase activity, as well as parathion-induced tremors and the progression of other signs and symptoms of parathion poisoning. These data suggest that redox cycling compounds, such as menadione, have the potential to effectively mitigate the toxicity of organophosphorus pesticides including parathion which require cytochrome P450-mediated activation. - Highlights: • Menadione redox cycles with cytochrome P450 reductase and generates reactive oxygen species. • Redox cycling inhibits cytochrome P450-mediated parathion metabolism. • Short term administration of menadione inhibits parathion toxicity by inhibiting paraoxon formation.

Vitamin K3 (menadione) redox cycling inhibits cytochrome P450-mediated metabolism and inhibits parathion intoxication

International Nuclear Information System (INIS)

Jan, Yi-Hua; Richardson, Jason R.; Baker, Angela A.; Mishin, Vladimir; Heck, Diane E.; Laskin, Debra L.; Laskin, Jeffrey D.

2015-01-01

Parathion, a widely used organophosphate insecticide, is considered a high priority chemical threat. Parathion toxicity is dependent on its metabolism by the cytochrome P450 system to paraoxon (diethyl 4-nitrophenyl phosphate), a cytotoxic metabolite. As an effective inhibitor of cholinesterases, paraoxon causes the accumulation of acetylcholine in synapses and overstimulation of nicotinic and muscarinic cholinergic receptors, leading to characteristic signs of organophosphate poisoning. Inhibition of parathion metabolism to paraoxon represents a potential approach to counter parathion toxicity. Herein, we demonstrate that menadione (methyl-1,4-naphthoquinone, vitamin K3) is a potent inhibitor of cytochrome P450-mediated metabolism of parathion. Menadione is active in redox cycling, a reaction mediated by NADPH-cytochrome P450 reductase that preferentially uses electrons from NADPH at the expense of their supply to the P450s. Using human recombinant CYP 1A2, 2B6, 3A4 and human liver microsomes, menadione was found to inhibit the formation of paraoxon from parathion. Administration of menadione bisulfite (40 mg/kg, ip) to rats also reduced parathion-induced inhibition of brain cholinesterase activity, as well as parathion-induced tremors and the progression of other signs and symptoms of parathion poisoning. These data suggest that redox cycling compounds, such as menadione, have the potential to effectively mitigate the toxicity of organophosphorus pesticides including parathion which require cytochrome P450-mediated activation. - Highlights: • Menadione redox cycles with cytochrome P450 reductase and generates reactive oxygen species. • Redox cycling inhibits cytochrome P450-mediated parathion metabolism. • Short term administration of menadione inhibits parathion toxicity by inhibiting paraoxon formation.

Gingival tissue-produced inhibition of platelet aggregation and the loss of inhibition in streptozotocin-induced diabetic rats

Energy Technology Data Exchange (ETDEWEB)

Kawamura, Keiichiroh; Tamai, Kazuharu; Shirakawa, Masaharu; Okamoto, Hiroshi; Dohi, Toshihiro; Tsujimoto, Akira

1988-01-01

Addition of medium incubated with normal rat gingival tissue to platelet-rich plasma inhibited ADP-induced platelet aggregation. The ability of rat gingiva to produce activity inhibiting platelet aggregation was enhanced by the addition of arachidonic acid. Diabetic rat gingiva failed to inhibit platelet aggregation but did produce the anti-platelet aggregating activity in the presence of arachidonic acid. Indomethacin blocked the production of anti-platelet aggregating activity. There was no difference in conversion of (1-/sup 14/C)arachidonic acid to prostaglandins by normal and diabetic rat gingiva. These results suggest that an arachidonic acid metabolite released from gingiva during incubation inhibits platelet aggregation, and the synthesis of the metabolite is impaired in diabetic rat gingiva. A decrease in availability of arachidonic acid may be a causal factor of the defect in diabetic rat gingiva.

Gingival tissue-produced inhibition of platelet aggregation and the loss of inhibition in streptozotocin-induced diabetic rats

International Nuclear Information System (INIS)

Kawamura, Keiichiroh; Tamai, Kazuharu; Shirakawa, Masaharu; Okamoto, Hiroshi; Dohi, Toshihiro; Tsujimoto, Akira

1988-01-01

Addition of medium incubated with normal rat gingival tissue to platelet-rich plasma inhibited ADP-induced platelet aggregation. The ability of rat gingiva to produce activity inhibiting platelet aggregation was enhanced by the addition of arachidonic acid. Diabetic rat gingiva failed to inhibit platelet aggregation but did produce the anti-platelet aggregating activity in the presence of arachidonic acid. Indomethacin blocked the production of anti-platelet aggregating activity. There was no difference in conversion of [1- 14 C]arachidonic acid to prostaglandins by normal and diabetic rat gingiva. These results suggest that an arachidonic acid metabolite released from gingiva during incubation inhibits platelet aggregation, and the synthesis of the metabolite is impaired in diabetic rat gingiva. A decrease in availability of arachidonic acid may be a causal factor of the defect in diabetic rat gingiva. (author)

Inhibition of apparent photosynthesis by nitrogen oxides

Energy Technology Data Exchange (ETDEWEB)

Hill, A C; Bennett, J H

1970-01-01

The nitrogen oxides (NO/sub 2/ and NO) inhibited apparent photosynthesis of oats and alfalfa at concentrations below those required to cause visible injury. There appeared to be a threshold concentration of about 0.6 ppm for each pollutant. An additive effect in depressing apparent photosynthesis occurred when the plants were exposed to a mixture of NO and NO/sub 2/. Although NO produced a more rapid effect on the plants, lower concentrations of NO/sub 2/ were required to cause a given inhibition after 2 hour of exposure. Inhibition by nitric oxide was more closely related to its partial pressure than was inhibition by NO/sub 2/.

Peptide inhibition of human cytomegalovirus infection

Directory of Open Access Journals (Sweden)

Morris Cindy A

2011-02-01

Full Text Available Abstract Background Human cytomegalovirus (HCMV is the most prevalent congenital viral infection in the United States and Europe causing significant morbidity and mortality to both mother and child. HCMV is also an opportunistic pathogen in immunocompromised individuals, including human immunodeficiency virus (HIV- infected patients with AIDS, and solid organ and allogeneic stem cell transplantation recipients. Current treatments for HCMV-associated diseases are insufficient due to the emergence of drug-induced resistance and cytotoxicity, necessitating novel approaches to limit HCMV infection. The aim of this study was to develop therapeutic peptides targeting glycoprotein B (gB, a major glycoprotein of HCMV that is highly conserved across the Herpesviridae family, that specifically inhibit fusion of the viral envelope with the host cell membrane preventing HCMV entry and infection. Results Using the Wimley-White Interfacial Hydrophobicity Scale (WWIHS, several regions within gB were identified that display a high potential to interact with lipid bilayers of cell membranes and hydrophobic surfaces within proteins. The ability of synthetic peptides analogous to WWIHS-positive sequences of HCMV gB to inhibit viral infectivity was evaluated. Human foreskin fibroblasts (HFF were infected with the Towne-GFP strain of HCMV (0.5 MOI, preincubated with peptides at a range of concentrations (78 nm to 100 μM, and GFP-positive cells were visualized 48 hours post-infection by fluorescence microscopy and analyzed quantitatively by flow cytometry. Peptides that inhibited HCMV infection demonstrated different inhibitory concentration curves indicating that each peptide possesses distinct biophysical properties. Peptide 174-200 showed 80% inhibition of viral infection at a concentration of 100 μM, and 51% and 62% inhibition at concentrations of 5 μM and 2.5 μM, respectively. Peptide 233-263 inhibited infection by 97% and 92% at concentrations of 100 �

STIR: Assessing and Training Response Inhibition Abilities

Science.gov (United States)

2014-07-30

Learning to stop responding to alcohol cues reduces alcohol intake via reduced affective associations rather than increased response inhibition. Addiction ...requires an abstract application of the core learning principle1,2, and viable examples are often hard to find and/or assess. If exposure to non...inhibition training that expands upon previous successful “near transfer” response inhibition training efforts—such as treating alcohol addictions by

Inhibition of cortiocosteroidogenesis by delta-9-tetrahydrocannabinol.

Science.gov (United States)

Warner, W; Harris, L S; Carchman, R A

1977-12-01

ACTH, cholera toxin, cyclic AMP but not pregnenolone-induced steroidogenesis in Y-1 functional mouse adrenal tumor cells was significantly inhibited by delta-9-tetrahydrocannabinol, cannabidiol, and cannabinol. The inhibition of steroidogenesis could not be correlated with a general depression in cell function or viability. The data suggest that cannabinoids inhibit corticosteroidogenesis at a site between the synthesis of cAMP and of pregnenolone.

Generalising tree traversals and tree transformations to DAGs

DEFF Research Database (Denmark)

Bahr, Patrick; Axelsson, Emil

2017-01-01

We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead. The resul......We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead...... as the complementing theory with a number of examples....

Independencies Induced from a Graphical Markov Model After Marginalization and Conditioning: The R Package ggm

Directory of Open Access Journals (Sweden)

Giovanni M. Marchetti

2006-02-01

Full Text Available We describe some functions in the R package ggm to derive from a given Markov model, represented by a directed acyclic graph, different types of graphs induced after marginalizing over and conditioning on some of the variables. The package has a few basic functions that find the essential graph, the induced concentration and covariance graphs, and several types of chain graphs implied by the directed acyclic graph (DAG after grouping and reordering the variables. These functions can be useful to explore the impact of latent variables or of selection effects on a chosen data generating model.

Contour detection based on nonclassical receptive field inhibition

NARCIS (Netherlands)

Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.

We propose a biologically motivated computational step, called nonclassical receptive field (non-CRF) inhibition, more generally surround inhibition or suppression, to improve contour detection in machine vision. Non-CRF inhibition is exhibited by 80% of the orientation-selective neurons in the

Regulation of spatial selectivity by crossover inhibition.

Science.gov (United States)

Cafaro, Jon; Rieke, Fred

2013-04-10

Signals throughout the nervous system diverge into parallel excitatory and inhibitory pathways that later converge on downstream neurons to control their spike output. Converging excitatory and inhibitory synaptic inputs can exhibit a variety of temporal relationships. A common motif is feedforward inhibition, in which an increase (decrease) in excitatory input precedes a corresponding increase (decrease) in inhibitory input. The delay of inhibitory input relative to excitatory input originates from an extra synapse in the circuit shaping inhibitory input. Another common motif is push-pull or "crossover" inhibition, in which increases (decreases) in excitatory input occur together with decreases (increases) in inhibitory input. Primate On midget ganglion cells receive primarily feedforward inhibition and On parasol cells receive primarily crossover inhibition; this difference provides an opportunity to study how each motif shapes the light responses of cell types that play a key role in visual perception. For full-field stimuli, feedforward inhibition abbreviated and attenuated responses of On midget cells, while crossover inhibition, though plentiful, had surprisingly little impact on the responses of On parasol cells. Spatially structured stimuli, however, could cause excitatory and inhibitory inputs to On parasol cells to increase together, adopting a temporal relation very much like that for feedforward inhibition. In this case, inhibitory inputs substantially abbreviated a cell's spike output. Thus inhibitory input shapes the temporal stimulus selectivity of both midget and parasol ganglion cells, but its impact on responses of parasol cells depends strongly on the spatial structure of the light inputs.

The development of children's inhibition: Does parenting matter?

OpenAIRE

Roskam, I.; Stievenart, Marie; Meunier, J.-C.; Noël, M.-P.

2014-01-01

Whereas a large body of research has investigated the maturation of inhibition in relation to the prefrontal cortex, far less research has been devoted to environmental factors that could contribute to inhibition improvement. The aim of the current study was to test whether and to what extent parenting matters for inhibition development from 2 to 8. years of age. Data were collected from 421 families, with 348 mother-child dyads and 342 father-child dyads participating. Children's inhibition ...

Antimicrobial peptide evolution in the Asiatic honey bee Apis cerana.

Directory of Open Access Journals (Sweden)

Peng Xu

Full Text Available The Asiatic honeybee, Apis cerana Fabricius, is an important honeybee species in Asian countries. It is still found in the wild, but is also one of the few bee species that can be domesticated. It has acquired some genetic advantages and significantly different biological characteristics compared with other Apis species. However, it has been less studied, and over the past two decades, has become a threatened species in China. We designed primers for the sequences of the four antimicrobial peptide cDNA gene families (abaecin, defensin, apidaecin, and hymenoptaecin of the Western honeybee, Apis mellifera L. and identified all the antimicrobial peptide cDNA genes in the Asiatic honeybee for the first time. All the sequences were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR. In all, 29 different defensin cDNA genes coding 7 different defensin peptides, 11 different abaecin cDNA genes coding 2 different abaecin peptides, 13 different apidaecin cDNA genes coding 4 apidaecin peptides and 34 different hymenoptaecin cDNA genes coding 13 different hymenoptaecin peptides were cloned and identified from the Asiatic honeybee adult workers. Detailed comparison of these four antimicrobial peptide gene families with those of the Western honeybee revealed that there are many similarities in the quantity and amino acid components of peptides in the abaecin, defensin and apidaecin families, while many more hymenoptaecin peptides are found in the Asiatic honeybee than those in the Western honeybee (13 versus 1. The results indicated that the Asiatic honeybee adult generated more variable antimicrobial peptides, especially hymenoptaecin peptides than the Western honeybee when stimulated by pathogens or injury. This suggests that, compared to the Western honeybee that has a longer history of domestication, selection on the Asiatic honeybee has favored the generation of more variable antimicrobial peptides as protection against pathogens.

Antimicrobial peptide evolution in the Asiatic honey bee Apis cerana.

Science.gov (United States)

Xu, Peng; Shi, Min; Chen, Xue-Xin

2009-01-01

The Asiatic honeybee, Apis cerana Fabricius, is an important honeybee species in Asian countries. It is still found in the wild, but is also one of the few bee species that can be domesticated. It has acquired some genetic advantages and significantly different biological characteristics compared with other Apis species. However, it has been less studied, and over the past two decades, has become a threatened species in China. We designed primers for the sequences of the four antimicrobial peptide cDNA gene families (abaecin, defensin, apidaecin, and hymenoptaecin) of the Western honeybee, Apis mellifera L. and identified all the antimicrobial peptide cDNA genes in the Asiatic honeybee for the first time. All the sequences were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR). In all, 29 different defensin cDNA genes coding 7 different defensin peptides, 11 different abaecin cDNA genes coding 2 different abaecin peptides, 13 different apidaecin cDNA genes coding 4 apidaecin peptides and 34 different hymenoptaecin cDNA genes coding 13 different hymenoptaecin peptides were cloned and identified from the Asiatic honeybee adult workers. Detailed comparison of these four antimicrobial peptide gene families with those of the Western honeybee revealed that there are many similarities in the quantity and amino acid components of peptides in the abaecin, defensin and apidaecin families, while many more hymenoptaecin peptides are found in the Asiatic honeybee than those in the Western honeybee (13 versus 1). The results indicated that the Asiatic honeybee adult generated more variable antimicrobial peptides, especially hymenoptaecin peptides than the Western honeybee when stimulated by pathogens or injury. This suggests that, compared to the Western honeybee that has a longer history of domestication, selection on the Asiatic honeybee has favored the generation of more variable antimicrobial peptides as protection against pathogens.

Innate immune defences in the human endometrium

Directory of Open Access Journals (Sweden)

Kelly Rodney W

2003-11-01

Full Text Available Abstract The human endometrium is an important site of innate immune defence, giving protection against uterine infection. Such protection is critical to successful implantation and pregnancy. Infection is a major cause of preterm birth and can also cause infertility and ectopic pregnancy. Natural anti-microbial peptides are key mediators of the innate immune system. These peptides, between them, have anti-bacterial, anti-fungal and anti-viral activity and are expressed at epithelial surfaces throughout the female genital tract. Two families of natural anti-microbials, the defensins and the whey acidic protein (WAP motif proteins, appear to be prominent in endometrium. The human endometrial epithelium expresses beta-defensins 1–4 and the WAP motif protein, secretory leukocyte protease inhibitor. Each beta-defensin has a different expression profile in relation to the stage of the menstrual cycle, providing potential protection throughout the cycle. Secretory leukocyte protease inhibitor is expressed during the secretory phase of the cycle and has a range of possible roles including anti-protease and anti-microbial activity as well as having effects on epithelial cell growth. The leukocyte populations in the endometrium are also a source of anti-microbial production. Neutrophils are a particularly rich source of alpha-defensins, lactoferrin, lysozyme and the WAP motif protein, elafin. The presence of neutrophils during menstruation will enhance anti-microbial protection at a time when the epithelial barrier is disrupted. Several other anti-microbials including the natural killer cell product, granulysin, are likely to have a role in endometrium. The sequential production of natural anti-microbial peptides by the endometrium throughout the menstrual cycle and at other sites in the female genital tract will offer protection from many pathogens, including those that are sexually transmitted.

Aspartate inhibits Staphylococcus aureus biofilm formation.

Science.gov (United States)

Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

2015-04-01

Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Structure–inhibition relationship of ginsenosides towards UDP-glucuronosyltransferases (UGTs)

International Nuclear Information System (INIS)

Fang, Zhong-Ze; Cao, Yun-Feng; Hu, Cui-Min; Hong, Mo; Sun, Xiao-Yu; Ge, Guang-Bo; Liu, Yong; Zhang, Yan-Yan; Yang, Ling; Sun, Hong-Zhi

2013-01-01

The wide utilization of ginseng provides the high risk of herb–drug interaction (HDI) with many clinical drugs. The inhibition of ginsenosides towards drug-metabolizing enzymes (DMEs) has been regarded as an important reason for herb–drug interaction (HDI). Compared with the deep studies on the ginsenosides' inhibition towards cytochrome P450 (CYP), the inhibition of ginsenosides towards the important phase II enzymes UDP-glucuronosyltransferases (UGTs) remains to be unclear. The present study aims to evaluate the inhibition behavior of ginsenosides towards important UGT isoforms located in the liver and intestine using in vitro methods. The recombinant UGT isoform-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed as in vitro probe reaction. The results showed that structure-dependent inhibition existed for the inhibition of ginsenosides towards UGT isoforms. To clarify the possibility of in vivo herb–drug interaction induced by this kind of inhibition, the ginsenoside Rg 3 was selected as an example, and the inhibition kinetic type and parameters (K i ) were determined. Rg 3 competitively inhibited UGT1A7, 2B7 and 2B15-catalyzed 4-MU glucuronidation reaction, and exerted noncompetitive inhibition towards UGT1A8-catalyzed 4-MU glucuronidation. The inhibition parameters (K i values) were calculated to be 22.6, 7.9, 1.9, and 2.0 μM for UGT1A7, 1A8, 2B7 and 2B15. Using human maximum plasma concentration of Rg 3 (400 ng/ml (0.5 μM)) after intramuscular injection of 60 mg Rg 3 , the area under the plasma concentration-time curve (AUC) was extrapolated to increase by 2.2%, 6.3%, 26.3%, and 25% for the co-administered drugs completely undergoing the metabolism catalyzed by UGT1A7, 1A8, 2B7 and 2B15, respectively. All these results indicated that the ginsenosides' inhibition towards UGT isoforms might be an important reason for ginseng–drug interaction. - Highlights: ► Structure-dependent inhibition of ginsenoside towards UDP

Structure–inhibition relationship of ginsenosides towards UDP-glucuronosyltransferases (UGTs)

Energy Technology Data Exchange (ETDEWEB)

Fang, Zhong-Ze [The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); Joint Center for Translational Medicine, Dalian Institute of Chemical Physics Chinese Academy of Sciences and The first Affiliated Hospital of Liaoning Medical University, No.457, Zhongshan Road, Dalian 116023 (China); Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); Cao, Yun-Feng [Key Laboratory of Contraceptives and Devices Research(NPFPC),Shanghai Engineer and Technology Research Center of Reproductive Health Drug and Devices, Shanghai Institute of Planned Parenthood Research, Shanghai 200032 (China); Joint Center for Translational Medicine, Dalian Institute of Chemical Physics Chinese Academy of Sciences and The first Affiliated Hospital of Liaoning Medical University, No.457, Zhongshan Road, Dalian 116023 (China); Hu, Cui-Min [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); Hong, Mo; Sun, Xiao-Yu [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics Chinese Academy of Sciences and The first Affiliated Hospital of Liaoning Medical University, No.457, Zhongshan Road, Dalian 116023 (China); Ge, Guang-Bo; Liu, Yong; Zhang, Yan-Yan; Yang, Ling [Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian (China); Sun, Hong-Zhi, E-mail: zzfang228@gmail.com [The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China)

2013-03-01

The wide utilization of ginseng provides the high risk of herb–drug interaction (HDI) with many clinical drugs. The inhibition of ginsenosides towards drug-metabolizing enzymes (DMEs) has been regarded as an important reason for herb–drug interaction (HDI). Compared with the deep studies on the ginsenosides' inhibition towards cytochrome P450 (CYP), the inhibition of ginsenosides towards the important phase II enzymes UDP-glucuronosyltransferases (UGTs) remains to be unclear. The present study aims to evaluate the inhibition behavior of ginsenosides towards important UGT isoforms located in the liver and intestine using in vitro methods. The recombinant UGT isoform-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed as in vitro probe reaction. The results showed that structure-dependent inhibition existed for the inhibition of ginsenosides towards UGT isoforms. To clarify the possibility of in vivo herb–drug interaction induced by this kind of inhibition, the ginsenoside Rg{sub 3} was selected as an example, and the inhibition kinetic type and parameters (K{sub i}) were determined. Rg{sub 3} competitively inhibited UGT1A7, 2B7 and 2B15-catalyzed 4-MU glucuronidation reaction, and exerted noncompetitive inhibition towards UGT1A8-catalyzed 4-MU glucuronidation. The inhibition parameters (K{sub i} values) were calculated to be 22.6, 7.9, 1.9, and 2.0 μM for UGT1A7, 1A8, 2B7 and 2B15. Using human maximum plasma concentration of Rg{sub 3} (400 ng/ml (0.5 μM)) after intramuscular injection of 60 mg Rg{sub 3}, the area under the plasma concentration-time curve (AUC) was extrapolated to increase by 2.2%, 6.3%, 26.3%, and 25% for the co-administered drugs completely undergoing the metabolism catalyzed by UGT1A7, 1A8, 2B7 and 2B15, respectively. All these results indicated that the ginsenosides' inhibition towards UGT isoforms might be an important reason for ginseng–drug interaction. - Highlights: ► Structure

Inhibition of autophagy initiation potentiates chemosensitivity in mesothelioma.

Science.gov (United States)

Follo, Carlo; Cheng, Yao; Richards, William G; Bueno, Raphael; Broaddus, Virginia Courtney

2018-03-01

The benefits of inhibiting autophagy in cancer are still controversial, with differences in outcome based on the type of tumor, the context and the particular stage of inhibition. Here, we investigated the impact of inhibiting autophagy at different stages on chemosensitivity using 3-dimensional (3D) models of mesothelioma, including ex vivo human tumor fragment spheroids. As shown by LC3B accumulation, we successfully inhibited autophagy using either an early stage ULK1/2 inhibitor (MRT 68921) or a late stage inhibitor (hydroxychloroquine). We found that inhibition of autophagy at the early stage, but not at late stage, potentiated chemosensitivity. This effect was seen only in those spheroids with high autophagy and active initiation at steady state. Inhibition of autophagy alone, at either early or late stage, did not cause cell death, showing that the inhibitors were non-toxic and that mesothelioma did not depend on autophagy at baseline, at least over 24 h. Using ATG13 puncta analysis, we found that autophagy initiation identified tumors that are more chemosensitive at baseline and after autophagy inhibition. Our results highlight a potential role of autophagy initiation in supporting mesothelioma cells during chemotherapy. Our work also highlights the importance of testing the inhibition of different stages in order to uncover the role of autophagy and the potential of its modulation in the treatment of cancer. © 2017 Wiley Periodicals, Inc.

Methanol Extract of Myelophycus caespitosus Inhibits the ...

African Journals Online (AJOL)

Methanol Extract of Myelophycus caespitosus Inhibits the Inflammatory Response in Lipopolysaccharidestimulated BV2 Microglial Cells by Downregulating NF-kB via Inhibition of the Akt Signaling Pathway.

Inhibiting the inevitable

DEFF Research Database (Denmark)

Shashoua, Yvonne

2006-01-01

conservation is to ‘buy time’ for the object. Inhibitive conservation of plastics involves the removal or reduction of factors causing or accelerating degradation including light, oxygen, acids, relative humidity and acidic breakdown products. Specific approaches to conservation have been developed......Once plastics objects are registered in museum collections, the institution becomes responsible for their long term preservation, until the end of their useful lifetime. Plastics appear to deteriorate faster than other materials in museum collections and have a useful lifetime between 5 and 25...... years. Preventive or inhibitive conservation involves controlling the environments in which objects are placed during storage and display, with the aim of slowing the major deterioration reactions. Once in progress, degradation of plastics cannot be stopped or reversed, so the aim of preventive...

Inhibition of chrysin on xanthine oxidase activity and its inhibition mechanism.

Science.gov (United States)

Lin, Suyun; Zhang, Guowen; Liao, Yijing; Pan, Junhui

2015-11-01

Chrysin, a bioactive flavonoid, was investigated for its potential to inhibit the activity of xanthine oxidase (XO), a key enzyme catalyzing xanthine to uric acid and finally causing gout. The kinetic analysis showed that chrysin possessed a strong inhibition on XO ability in a reversible competitive manner with IC50 value of (1.26±0.04)×10(-6)molL(-1). The results of fluorescence titrations indicated that chrysin bound to XO with high affinity, and the interaction was predominately driven by hydrogen bonds and van der Waals forces. Analysis of circular dichroism demonstrated that chrysin induced the conformational change of XO with increases in α-helix and β-sheet and reductions in β-turn and random coil structures. Molecular simulation revealed that chrysin interacted with the amino acid residues Leu648, Phe649, Glu802, Leu873, Ser876, Glu879, Arg880, Phe1009, Thr1010, Val1011 and Phe1013 located within the active cavity of XO. The mechanism of chrysin on XO activity may be the insertion of chrysin into the active site occupying the catalytic center of XO to avoid the entrance of xanthine and causing conformational changes in XO. Furthermore, the interaction assays indicated that chrysin and its structural analog apigenin exhibited an additive effect on inhibition of XO. Copyright © 2015 Elsevier B.V. All rights reserved.

Inhibition of AMPK catabolic action by GSK3

Science.gov (United States)

Suzuki, Tsukasa; Bridges, Dave; Nakada, Daisuke; Skiniotis, Georgios; Morrison, Sean J.; Lin, Jiandie; Saltiel, Alan R.; Inoki, Ken

2013-01-01

SUMMARY AMP-activated protein kinase (AMPK) regulates cellular energy homeostasis by inhibiting anabolic and activating catabolic processes. While AMPK activation has been extensively studied, mechanisms that inhibit AMPK remain elusive. Here we report that glycogen synthase kinase 3 (GSK3) inhibits AMPK function. GSK3 forms a stable complex with AMPK through interactions with the AMPK β regulatory subunit and phosphorylates the AMPK α catalytic subunit. This phosphorylation enhances the accessibility of the activation loop of the α subunit to phosphatases, thereby inhibiting AMPK kinase activity. Surprisingly, PI3K-Akt signaling, which is a major anabolic signaling and normally inhibits GSK3 activity, promotes GSK3 phosphorylation and inhibition of AMPK, thus revealing how AMPK senses anabolic environments in addition to cellular energy levels. Consistently, disrupting GSK3 function within the AMPK complex sustains higher AMPK activity and cellular catabolic processes even under anabolic conditions, indicating that GSK3 acts as a critical sensor for anabolic signaling to regulate AMPK. PMID:23623684

In vitro evaluation of single- and multi-strain probiotics: Inter-species inhibition between probiotic strains, and inhibition of pathogens.

Science.gov (United States)

Chapman, C M C; Gibson, G R; Rowland, I

2012-08-01

Many studies comparing the effects of single- and multi-strain probiotics on pathogen inhibition compare treatments with different concentrations. They also do not examine the possibility of inhibition between probiotic strains with a mixture. We tested the ability of 14 single-species probiotics to inhibit each other using a cross-streak assay, and agar spot test. We then tested the ability of 15 single-species probiotics and 5 probiotic mixtures to inhibit Clostridium difficile, Escherichia coli and S. typhimurium, using the agar spot test. Testing was done with mixtures created in two ways: one group contained component species incubated together, the other group of mixtures was made using component species which had been incubated separately, equalised to equal optical density, and then mixed in equal volumes. Inhibition was observed for all combinations of probiotics, suggesting that when used as such there may be inhibition between probiotics, potentially reducing efficacy of the mixture. Significant inter-species variation was seen against each pathogen. When single species were tested against mixtures, the multi-species preparations displayed significantly (p probiotic species will inhibit each other when incubated together in vitro, in many cases a probiotic mixture was more effective at inhibiting pathogens than its component species when tested at approximately equal concentrations of biomass. This suggests that using a probiotic mixture might be more effective at reducing gastrointestinal infections, and that creating a mixture using species with different effects against different pathogens may have a broader spectrum of action that a single provided by a single strain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Allosteric inhibition of SHP2 phosphatase inhibits cancers driven by receptor tyrosine kinases

Energy Technology Data Exchange (ETDEWEB)

Chen, Ying-Nan P.; LaMarche, Matthew J.; Chan, Ho Man; Fekkes, Peter; Garcia-Fortanet, Jorge; Acker, Michael G.; Antonakos, Brandon; Chen, Christine Hiu-Tung; Chen, Zhouliang; Cooke, Vesselina G.; Dobson, Jason R.; Deng, Zhan; Fei, Feng; Firestone, Brant; Fodor, Michelle; Fridrich, Cary; Gao, Hui; Grunenfelder, Denise; Hao, Huai-Xiang; Jacob, Jaison; Ho, Samuel; Hsiao, Kathy; Kang, Zhao B.; Karki, Rajesh; Kato, Mitsunori; Larrow, Jay; La Bonte, Laura R.; Lenoir, Francois; Liu, Gang; Liu, Shumei; Majumdar, Dyuti; Meyer, Matthew J.; Palermo, Mark; Perez, Lawrence; Pu, Minying; Price, Edmund; Quinn, Christopher; Shakya, Subarna; Shultz, Michael D.; Slisz, Joanna; Venkatesan, Kavitha; Wang, Ping; Warmuth, Markus; Williams, Sarah; Yang, Guizhi; Yuan, Jing; Zhang, Ji-Hu; Zhu, Ping; Ramsey, Timothy; Keen, Nicholas J.; Sellers, William R.; Stams, Travis; Fortin , Pascal D. (Novartis)

2016-06-29

The non-receptor protein tyrosine phosphatase SHP2, encoded by PTPN11, has an important role in signal transduction downstream of growth factor receptor signalling and was the first reported oncogenic tyrosine phosphatase1. Activating mutations of SHP2 have been associated with developmental pathologies such as Noonan syndrome and are found in multiple cancer types, including leukaemia, lung and breast cancer and neuroblastoma1, 2, 3, 4, 5. SHP2 is ubiquitously expressed and regulates cell survival and proliferation primarily through activation of the RAS–ERK signalling pathway2, 3. It is also a key mediator of the programmed cell death 1 (PD-1) and B- and T-lymphocyte attenuator (BTLA) immune checkpoint pathways6, 7. Reduction of SHP2 activity suppresses tumour cell growth and is a potential target of cancer therapy8, 9. Here we report the discovery of a highly potent (IC50 = 0.071 μM), selective and orally bioavailable small-molecule SHP2 inhibitor, SHP099, that stabilizes SHP2 in an auto-inhibited conformation. SHP099 concurrently binds to the interface of the N-terminal SH2, C-terminal SH2, and protein tyrosine phosphatase domains, thus inhibiting SHP2 activity through an allosteric mechanism. SHP099 suppresses RAS–ERK signalling to inhibit the proliferation of receptor-tyrosine-kinase-driven human cancer cells in vitro and is efficacious in mouse tumour xenograft models. Together, these data demonstrate that pharmacological inhibition of SHP2 is a valid therapeutic approach for the treatment of cancers.

Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis

Directory of Open Access Journals (Sweden)

Li Q

2013-07-01

Full Text Available Qingli Li,1,2 Mark J Lambrechts,1 Qiuyang Zhang,1 Sen Liu,1 Dongxia Ge,1 Rutie Yin,2 Mingrong Xi,2 Zongbing You1 1Departments of Structural and Cellular Biology and Orthopaedic Surgery, Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane Center for Stem Cell Research and Regenerative Medicine, and Tulane Center for Aging, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, People’s Republic of China Abstract: Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA, are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy. Keywords: serine hydroxymethyltransferase, prostate cancer, apoptosis

[Concepts of inhibition in psychiatry].

Science.gov (United States)

Auroux, Y; Bourrat, M M; Brun, J P

1978-01-01

Following a historical approach, the authors first describe the original development of the concept of inhibition in neurophysiology and then analyze the subsequent adaptations made in psychiatry around such concept including those of: -- Pavlov, Hull, Watson and the behaviorists, -- Freud and the Freudian School, -- clinicians and psychopharmacologists. The concept of inhibition has thus various meanings in psychiatry. Although some unity is achieved on the semiological level, this aspect cannot explain the extent of the process.

A Qualitative Approach to Enzyme Inhibition

Science.gov (United States)

Waldrop, Grover L.

2009-01-01

Most general biochemistry textbooks present enzyme inhibition by showing how the basic Michaelis-Menten parameters K[subscript m] and V[subscript max] are affected mathematically by a particular type of inhibitor. This approach, while mathematically rigorous, does not lend itself to understanding how inhibition patterns are used to determine the…

Antimicrobial Peptide Human Neutrophil Peptide 1 as a Potential Link Between Chronic Inflammation and Ductal Adenocarcinoma of the Pancreas.

Science.gov (United States)

Pausch, Thomas; Adolph, Sarah; Felix, Klaus; Bauer, Andrea S; Bergmann, Frank; Werner, Jens; Hartwig, Werner

Defensins are antimicrobial peptides playing a role in innate immunity, in epithelial cell regeneration, and in carcinogenesis of inflammation-triggered malignancies. We analyzed this role in pancreatic ductal adenocarcinoma (PDAC) in the context of its association with chronic pancreatitis (CP). Human tissue of healthy pancreas, CP, and PDAC was screened for defensins by immunohistochemistry. Defensin α 1 (human neutrophil peptide 1 [HNP-1]) expression was validated using mass spectrometry and microarray analysis. Human neutrophil peptide 1 expression and influences of proinflammatory cytokines (tumor necrosis factor α, interleukin 1β, and interferon γ) were studied in human pancreatic cancer cells (Colo 357, T3M4, PANC-1) and normal human pancreatic duct epithelial cells (HPDE). Accumulation of HNP-1 in malignant pancreatic ductal epithelia was seen. Spectrometry showed increased expression of HNP-1 in CP and even more in PDAC. At RNA level, no significant regulation was found. In cancer cells, HNP-1 expression was significantly higher than in HPDE. Proinflammatory cytokines significantly led to increased HNP-1 levels in culture supernatants and decreased levels in lysates of cancer cells. In HPDE cytokines significantly decreased HNP-1 levels. Inflammatory regulation of HNP-1 in PDAC tissue and cells indicates that HNP-1 may be a link between chronic inflammation and malignant transformation in the pancreas.

Combination of rapamycin, CI-1040, and 17-AAG inhibits metastatic capacity of prostate cancer via Slug inhibition.

Directory of Open Access Journals (Sweden)

Guanxiong Ding

Full Text Available Though prostate cancer (PCa has slow progression, the hormone refractory (HRCP and metastatic entities are substantially lethal and lack effective treatments. Transcription factor Slug is critical in regulating metastases of various tumors including PCa. Here we studied targeted therapy against Slug using combination of 3 drugs targeting 3 pathways respectively converging via Slug and further regulating PCa metastasis. Using in vitro assays we confirmed that Slug up-regulation incurred inhibition of E-cadherin that was anti-metastatic, and inhibited Bim-regulated cell apoptosis in PCa. Upstream PTEN/Akt, mTOR, Erk, and AR/Hsp90 pathways were responsible for Slug up-regulation and each of these could be targeted by rapamycin, CI-1040, and 17-AAG respectively. In 4 PCa cell lines with different traits in terms of PTEN loss and androgen sensitivity we tested the efficacy of mono- and combined therapy with the drugs. We found that metastatic capacity of the cells was maximally inhibited only when all 3 drugs were combined, due to the crosstalk between the pathways. 17-AAG decreases Slug expression via blockade of HSP90-dependent AR stability. Combination of rapamycin and CI-1040 diminishes invasiveness more potently in PCa cells that are androgen insensitive and with PTEN loss. Slug inhibited Bim-mediated apoptosis that could be rescued by mTOR/Erk/HSP90 inhibitors. Using mouse models for circulating PCa DNA quantification, we found that combination of mTOR/Erk/HSP90 inhibitors reduced circulating PCa cells in vivo significantly more potently than combination of 2 or monotherapy. Conclusively, combination of mTOR/Erk/Hsp90 inhibits metastatic capacity of prostate cancer via Slug inhibition.

The development of children's inhibition: does parenting matter?

Science.gov (United States)

Roskam, Isabelle; Stievenart, Marie; Meunier, Jean-Christophe; Noël, Marie-Pascale

2014-06-01

Whereas a large body of research has investigated the maturation of inhibition in relation to the prefrontal cortex, far less research has been devoted to environmental factors that could contribute to inhibition improvement. The aim of the current study was to test whether and to what extent parenting matters for inhibition development from 2 to 8years of age. Data were collected from 421 families, with 348 mother-child dyads and 342 father-child dyads participating. Children's inhibition capacities and parenting behaviors were assessed in a three-wave longitudinal data collection. The main analyses examined the impact of parenting on the development of children's inhibition capacities. They were conducted using a multilevel modeling (MLM) framework. The results lead to the conclusion that both mothers and fathers contribute through their child-rearing behavior to their children's executive functioning, even when controlling for age-related improvement (maturation) and important covariates such as gender, verbal IQ, and place of enrollment. More significant relations between children's inhibition development and parenting were displayed for mothers than for fathers. More precisely, parenting behaviors that involve higher monitoring, lower discipline, inconsistency and negative controlling, and a positive parenting style are associated with good development of inhibition capacities in children. Copyright © 2014 Elsevier Inc. All rights reserved.

Fatty acid synthase inhibition in human breast cancer cells leads to malonyl-CoA-induced inhibition of fatty acid oxidation and cytotoxicity.

Science.gov (United States)

Thupari, J N; Pinn, M L; Kuhajda, F P

2001-07-13

Inhibition of fatty acid synthase (FAS) induces apoptosis in human breast cancer cells in vitro and in vivo without toxicity to proliferating normal cells. We have previously shown that FAS inhibition causes a rapid increase in malonyl-CoA levels identifying malonyl-CoA as a potential trigger of apoptosis. In this study we further investigated the role of malonyl-CoA during FAS inhibition. We have found that: [i] inhibition of FAS with cerulenin causes carnitine palmitoyltransferase-1 (CPT-1) inhibition and fatty acid oxidation inhibition in MCF-7 human breast cancer cells likely mediated by elevation of malonyl-CoA; [ii] cerulenin cytotoxicity is due to the nonphysiological state of increased malonyl-CoA, decreased fatty acid oxidation, and decreased fatty acid synthesis; and [iii] the cytotoxic effect of cerulenin can be mimicked by simultaneous inhibition of CPT-1, with etomoxir, and fatty acid synthesis with TOFA, an acetyl-CoA carboxylase (ACC) inhibitor. This study identifies CPT-1 and ACC as two new potential targets for cancer chemotherapy. Copyright 2001 Academic Press.

On acyclicity of games with cycles

DEFF Research Database (Denmark)

Andersson, Klas Olof Daniel; Hansen, Thomas Dueholm; Gurvich, Vladimir

2010-01-01

We study restricted improvement cycles (ri-cycles) in finite positional n-person games with perfect information modeled by directed graphs (di-graphs) that may contain directed cycles (di-cycles). We assume that all these di-cycles form one outcome c, for example, a draw. We obtain criteria...

Exogenously triggered response inhibition in developmental stuttering.

Science.gov (United States)

Eggers, Kurt; De Nil, Luc F; Van den Bergh, Bea R H

2018-06-01

The purpose of the present study was to examine relations between children's exogenously triggered response inhibition and stuttering. Participants were 18 children who stutter (CWS; mean age = 9;01 years) and 18 children who not stutter (CWNS; mean age = 9;01 years). Participants were matched on age (±3 months) and gender. Response inhibition was assessed by a stop signal task (Verbruggen, Logan, & Stevens, 2008). Results suggest that CWS, compared to CWNS, perform comparable to CWNS in a task where response control is externally triggered. Our findings seem to indicate that previous questionnaire-based findings (Eggers, De Nil, & Van den Bergh, 2010) of a decreased efficiency of response inhibition cannot be generalized to all types of response inhibition. Copyright © 2018 Elsevier Inc. All rights reserved.

Release of Periplasmic Nucleotidase Induced by Human Antimicrobial Peptide in E. coli Causes Accumulation of the Immunomodulator Adenosine.

Directory of Open Access Journals (Sweden)

Andreia Bergamo Estrela

Full Text Available Previous work by our group described that human β-defensin-2 induces accumulation of extracellular adenosine (Ado in E. coli cultures through a non-lytic mechanism causing severe plasmolysis. Here, we investigate the presence of AMP as a direct precursor and the involvement of a bacterial enzyme in the generation of extracellular Ado by treated bacteria. Following hBD-2 treatment, metabolites were quantified in the supernatants using targeted HPLC-MS/MS analysis. Microbial growth was monitored by optical density and cell viability was determined by colony forming units counts. Phosphatase activity was measured using chromogenic substrate pNPP. The results demonstrate that defensin-treated E. coli strain W releases AMP in the extracellular space, where it is converted to Ado by a bacterial soluble factor. An increase in phosphatase activity in the supernatant was observed after peptide treatment, similar to the effect of sucrose-induced osmotic stress, suggesting that the periplasmic 5'nucleotidase (5'-NT is released following the plasmolysis event triggered by the peptide. Ado accumulation was enhanced in the presence of Co2+ ion and inhibited by EDTA, further supporting the involvement of a metallo-phosphatase such as 5'-NT in extracellular AMP conversion into Ado. The comparative analysis of hBD-induced Ado accumulation in different E. coli strains and in Pseudomonas aeruginosa revealed that the response is not correlated to the peptide's effect on cell viability, but indicates it might be dependent on the subcellular distribution of the nucleotidase. Taken together, these data shed light on a yet undescribed mechanism of host-microbial interaction: a human antimicrobial peptide inducing selective release of a bacterial enzyme (E. coli 5'-NT, leading to the formation of a potent immunomodulator metabolite (Ado.

Feedforward somatosensory inhibition is normal in cervical dystonia.

Science.gov (United States)

Ferrè, Elisa R; Ganos, Christos; Bhatia, Kailash P; Haggard, Patrick

2015-03-01

Insufficient cortical inhibition is a key pathophysiological finding in dystonia. Subliminal sensory stimuli were reported to transiently inhibit somatosensory processing. Here we investigated whether such subliminal feedforward inhibition is reduced in patients with cervical dystonia. Sixteen cervical dystonia patients and 16 matched healthy controls performed a somatosensory detection task. We measured the drop in sensitivity to detect a threshold-level digital nerve shock when it was preceded by a subliminal conditioning shock, compared to when it was not. Subliminal conditioning shocks reduced sensitivity to threshold stimuli to a similar extent in both patients and controls, suggesting that somatosensory subliminal feedforward inhibition is normal in cervical dystonia. Somatosensory feedforward inhibition was normal in this group of cervical dystonia patients. Our results qualify previous concepts of a general dystonic deficit in sensorimotor inhibitory processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Inhibition of GRP78 abrogates radioresistance in oropharyngeal carcinoma cells after EGFR inhibition by cetuximab.

Directory of Open Access Journals (Sweden)

Chaonan Sun

Full Text Available The EGFR-specific mAb cetuximab is one of the most effective treatments for oropharyngeal carcinoma, while patient responses to EGFR inhibitors given alone are modest. Combination treatment with radiation can improve the efficacy of treatment through increasing radiosensitivity, while resistance to radiation after administration of cetuximab limits its efficiency. Radiation and drugs can damage the endoplasmic reticulum (ER homeostatic state and result in ER stress (ERS, subsequently causing resistance to radiation and drugs. Whether the ERS pathway is involved in radioresistance after administration of cetuximab has not been reported. Herein, we show that cetuximab could increase the radiosensitivity of FaDu cells but not Detroit562 cells. In addition, cetuximab inhibited the radiation-induced activation of the ERS signalling pathway IRE1α/ATF6-GRP78 in FaDu cells, while this effect was absent in Detroit562 cells. Silencing GRP78 increased the radiosensitivity of oropharyngeal carcinoma cells and inhibited radiation-induced DNA double-strand-break (DSB repair and autophagy. More interestingly, silencing GRP78 abrogated resistance to cetuximab and radiation in Detroit562 cells and had a synergistic effect with cetuximab in increasing the radiosensitivity of FaDu cells. Immunohistochemistry showed that overexpression of both GRP78 and EGFR was associated with a poor prognosis in oropharyngeal carcinoma patients (P<0.05. Overall, the results of this study show that radioresistance after EGFR inhibition by cetuximab is mediated by the ERS signalling pathway IRE1α/ATF6-GRP78. This suppression was consequently unable to inhibit radiation-induced DSB repair and autophagy in oropharyngeal carcinoma cells, which conferred resistance to radiotherapy and cetuximab. These results suggest that the cooperative effects of radiotherapy and cetuximab could be further improved by inhibiting GRP78 in non-responsive oropharyngeal carcinoma patients.

Contrasting neural effects of aging on proactive and reactive response inhibition

NARCIS (Netherlands)

Bloemendaal, Mirjam; Zandbelt, Bram; Wegman, Joost; Rest, van de O.; Cools, Roshan; Aarts, Esther

2016-01-01

Two distinct forms of response inhibition may underlie observed deficits in response inhibition in aging. We assessed whether age-related neurocognitive impairments in response inhibition reflect deficient reactive inhibition (outright stopping) or also deficient proactive inhibition

Inhibition of Retinoblastoma Protein Inactivation

Science.gov (United States)

2017-11-01

CONTRACT NUMBER Inhibition of Retinoblastoma Protein Inactivation 5b. GRANT NUMBER W81XWH-14-1-0329 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Seth M...confirmed 108 compounds as giving a dose-response curve with at least 30% inhibition at 10 µM. The flowchart of hit progression is shown on the...Cancer Research Program under Award No. W81XWH-14-1-0329 to S.M.R. Opinions, interpretations, conclusions, and recommendations are those of the author

Differential effects of cognitive inhibition and intelligence on creativity

OpenAIRE

Benedek, Mathias; Franz, Fabiola; Heene, Moritz; Neubauer, Aljoscha C.

2012-01-01

There are different conceptions about how cognitive inhibition is related to creativity. Creativity has either been associated with effective inhibition, or with disinhibition, or with an adaptive engagement of inhibition. In this study, we examined the relationship of cognitive inhibition, assessed by means of the random motor generation task, with different measures of creativity. We also analyzed whether this relation is mediated by intelligence. We generally found a positive correlation o...

Polysulfonate suramin inhibits Zika virus infection.

Science.gov (United States)

Tan, Chee Wah; Sam, I-Ching; Chong, Wei Lim; Lee, Vannajan Sanghiran; Chan, Yoke Fun

2017-07-01

Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log 10  PFU viral reduction with IC 50 value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor. Copyright © 2017 Elsevier B.V. All rights reserved.

Ketoconazole inhibits the cellular uptake of anandamide via inhibition of FAAH at pharmacologically relevant concentrations.

Directory of Open Access Journals (Sweden)

Emmelie Björklund

Full Text Available The antifungal compound ketoconazole has, in addition to its ability to interfere with fungal ergosterol synthesis, effects upon other enzymes including human CYP3A4, CYP17, lipoxygenase and thromboxane synthetase. In the present study, we have investigated whether ketoconazole affects the cellular uptake and hydrolysis of the endogenous cannabinoid receptor ligand anandamide (AEA.The effects of ketoconazole upon endocannabinoid uptake were investigated using HepG2, CaCo2, PC-3 and C6 cell lines. Fatty acid amide hydrolase (FAAH activity was measured in HepG2 cell lysates and in intact C6 cells. Ketoconazole inhibited the uptake of AEA by HepG2 cells and CaCo2 cells with IC50 values of 17 and 18 µM, respectively. In contrast, it had modest effects upon AEA uptake in PC-3 cells, which have a low expression of FAAH. In cell-free HepG2 lysates, ketoconazole inhibited FAAH activity with an IC50 value (for the inhibitable component of 34 µM.The present study indicates that ketoconazole can inhibit the cellular uptake of AEA at pharmacologically relevant concentrations, primarily due to its effects upon FAAH. Ketoconazole may be useful as a template for the design of dual-action FAAH/CYP17 inhibitors as a novel strategy for the treatment of prostate cancer.

Attention Inhibition Training Can Reduce Betel-Nut Chewing Time

Directory of Open Access Journals (Sweden)

Ming-Chou Ho

2011-05-01

Full Text Available Betel nut (or areca is the fourth most commonly used drug worldwide after tobacco, alcohol, and caffeine. Many chemical ingredients of betel nut are carcinogenic. We examined whether the manipulation of attentional inhibition toward the areca-related stimuli could affect betel-nut chewing time. Three matched groups of habitual chewers were recruited: inhibit-areca, inhibit-non-areca, and control. This study consisted of a Go/No-Go task for inhibition training, followed by a taste test for observing chewing behavior. The Go/No-Go task constituted three phases (pretest, training and posttest. In the taste test, the habitual chewers were asked to rate the flavors of one betel nut and one gum. The purpose (blind to the chewers of this taste test was to observe whether their picking order and chewing time were affected by experimental manipulation. Results from the Go/No-Go task showed successful training. Further, the training groups (the inhibit-areca and inhibit-non-areca groups showed a significant reduction in betel nut chewing time, in comparison to the control group. Since both training groups showed reduced chewing time, the inhibition training may affect general control ability, in regardless of the stimulus (areca or not to be inhibited. Reduced chewing time is important for reducing areca-related diseases.

Simvastatin inhibits Candida albicans biofilm in vitro.

Science.gov (United States)

Liu, Geoffrey; Vellucci, Vincent F; Kyc, Stephanie; Hostetter, Margaret K

2009-12-01

By inhibiting the conversion of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) to mevalonate, statins impair cholesterol metabolism in humans. We reasoned that statins might similarly interfere with the biosynthesis of ergosterol, the major sterol of the yeast cell membrane. As assessed by spectrophotometric and microscopic analysis, significant inhibition of biofilm production was noted after 16-h incubation with 1, 2.5, and 5 muM simvastatin, concentrations that did not affect growth, adhesion, or hyphal formation by C. albicans in vitro. Higher concentrations (10, 20, and 25 muM simvastatin) inhibited biofilm by >90% but also impaired growth. Addition of exogenous ergosterol (90 muM) overcame the effects of 1 and 2.5 muM simvastatin, suggesting that at least one mechanism of inhibition is interference with ergosterol biosynthesis. Clinical isolates from blood, skin, and mucosal surfaces produced biofilms; biofilms from bloodstream isolates were similarly inhibited by simvastatin. In the absence of fungicidal activity, simvastatin's interruption of a critical step in an essential metabolic pathway, highly conserved from yeast to man, has unexpected effects on biofilm production by a eukaryotic pathogen.

Corrosion inhibition by lithium zinc phosphate pigment

International Nuclear Information System (INIS)

Alibakhshi, E.; Ghasemi, E.; Mahdavian, M.

2013-01-01

Highlights: •Synthesis of lithium zinc phosphate (LZP) by chemical co-precipitation method. •Corrosion inhibition activity of pigments compare with zinc phosphate (ZP). •LZP showed superior corrosion inhibition effect in EIS measurements. •Evaluation of adhesion strength and dispersion stability. -- Abstract: Lithium zinc phosphate (LZP) has been synthesized through a co-precipitation process and characterized by XRD and IR spectroscopy. The inhibitive performances of this pigment for corrosion of mild steel have been discussed in comparison with the zinc phosphate (ZP) in the pigment extract solution by means of EIS and in the epoxy coating by means of salt spray. The EIS and salt spray results revealed the superior corrosion inhibitive effect of LZP compared to ZP. Moreover, adhesion strength and dispersion stability of the pigmented epoxy coating showed the advantage of LZP compared to ZP

Plastics for corrosion inhibition

CERN Document Server

Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

2005-01-01

The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

Terbinafine inhibits gap junctional intercellular communication.

Science.gov (United States)

Lee, Ju Yeun; Yoon, Sei Mee; Choi, Eun Ju; Lee, Jinu

2016-09-15

Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca(2+) concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. Copyright © 2016 Elsevier Inc. All rights reserved.

7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

African Journals Online (AJOL)

In B16F10 and A375 cells, treatment with PEC caused the inhibition ... Conclusion: PEC inhibited melanoma cell proliferation, apparently by blocking the cell cycle at G0/G1 .... all statistical analyses. .... Financial support from the Department of.

The pharmacology of visuospatial attention and inhibition

NARCIS (Netherlands)

Logemann, H.N.A.

2013-01-01

Attention and inhibition are of vital importance in everyday functioning. Problems of attention and inhibition are central to disorders such as Attention Deficit/Hyperactivity Disorder (ADHD). Both bias and disengagement key components of visuospatial attention. Bias refers to neuronal signals that

Quorum sensing inhibition

DEFF Research Database (Denmark)

Persson, T.; Givskov, Michael Christian; Nielsen, J.

2005-01-01

/receptor transcriptional regulator in some clinically relevant Gram-negative bacteria. The present review contains all reported compound types that are currently known to inhibit the QS transcriptional regulator in Gram-negative bacteria. These compounds are sub-divided into two main groups, one comprising structural...

Chemical mechanism of the fluoride-inhibition of fermentation

Energy Technology Data Exchange (ETDEWEB)

Warburg, O; Christian, W

1941-08-01

Among the fluoride-sensitive fermentation elements, enolase is the most sensitive. An investigation was made, quantitatively, of fluoride inhibition for chemically pure magnesium-enolase using an optical enolase test. Data show that the effective compound for fluoride inhibition is a complex magnesium-fluoro-phosphate and that the magnesium-fluoro-phosphate inhibits fermentation by combining proportionally to its concentration with the ferment-protein in a dissociating manner.

Fluoxetine-induced inhibition of synaptosomal [3H]5-HT release: Possible Ca2+-channel inhibition

International Nuclear Information System (INIS)

Stauderman, K.A.; Gandhi, V.C.; Jones, D.J.

1992-01-01

Fluoxetine, a selective 5-Ht uptake inhibitor, inhibited 15 mM K + -induced [ 3 H]5-HT release from rat spinal cord and cortical synaptosomes at concentrations > 0.5 uM. This effect reflected a property shared by another selective 5-HT uptake inhibitor paroxetine but not by less selective uptake inhibitors such as amitriptyline, desipramine, imipramine or nortriptyline. Inhibition of release by fluoxetine was inversely related to both the concentration of K + used to depolarize the synaptosomes and the concentration of external Ca 2+ . Experiments aimed at determining a mechanism of action revealed that fluoxetine did not inhibit voltage-independent release of [ 3 H]5-HT release induced by the Ca 2+ -ionophore A 23187 or Ca 2+ -independent release induced by fenfluramine. Moreover the 5-HT autoreceptor antagonist methiothepin did not reverse the inhibitory actions of fluoxetine on K + -induced release. Further studies examined the effects of fluoxetine on voltage-dependent Ca 2+ channels and Ca 2+ entry

Attention Inhibition Training Can Reduce Betel-Nut Chewing Time

OpenAIRE

Ho, Ming-Chou; Li, Ren-Hau; Tang, Tze-Chun

2011-01-01

Betel nut (or areca) is the fourth most commonly used drug worldwide after tobacco, alcohol, and caffeine. Many chemical ingredients of betel nut are carcinogenic. We examined whether the manipulation of attentional inhibition toward the areca-related stimuli could affect betel-nut chewing time. Three matched groups of habitual chewers were recruited: inhibit-areca, inhibit-non-areca, and control. This study consisted of a Go/No-Go task for inhibition training, followed by a taste test for ob...

3-Bromopyruvate inhibits human gastric cancer tumor growth in nude mice via the inhibition of glycolysis.

Science.gov (United States)

Xian, Shu-Lin; Cao, Wei; Zhang, Xiao-Dong; Lu, Yun-Fei

2015-02-01

Tumor cells primarily depend upon glycolysis in order to gain energy. Therefore, the inhibition of glycolysis may inhibit tumor growth. Our previous study demonstrated that 3-bromopyruvate (3-BrPA) inhibited gastric cancer cell proliferation in vitro . However, the ability of 3-BrPA to suppress tumor growth in vivo, and its underlying mechanism, have yet to be elucidated. The aim of the present study was to investigate the inhibitory effect of 3-BrPA in an animal model of gastric cancer. It was identified that 3-BrPA exhibited strong inhibitory effects upon xenograft tumor growth in nude mice. In addition, the antitumor function of 3-BrPA exhibited a dose-effect association, which was similar to that of the chemotherapeutic agent, 5-fluorouracil. Furthermore, 3-BrPA exhibited low toxicity in the blood, liver and kidneys of the nude mice. The present study hypothesized that the inhibitory effect of 3-BrPA is achieved through the inhibition of hexokinase activity, which leads to the downregulation of B-cell lymphoma 2 (Bcl-2) expression, the upregulation of Bcl-2-associated X protein expression and the subsequent activation of caspase-3. These data suggest that 3-BrPA may be a novel therapy for the treatment of gastric cancer.

Effect of overall feedback inhibition in unbranched biosynthetic pathways.

Science.gov (United States)

Alves, R; Savageau, M A

2000-11-01

We have determined the effects of control by overall feedback inhibition on the systemic behavior of unbranched metabolic pathways with an arbitrary pattern of other feedback inhibitions by using a recently developed numerical generalization of Mathematically Controlled Comparisons, a method for comparing the function of alternative molecular designs. This method allows the rigorous determination of the changes in systemic properties that can be exclusively attributed to overall feedback inhibition. Analytical results show that the unbranched pathway can achieve the same steady-state flux, concentrations, and logarithmic gains with respect to changes in substrate, with or without overall feedback inhibition. The analytical approach also shows that control by overall feedback inhibition amplifies the regulation of flux by the demand for end product while attenuating the sensitivity of the concentrations to the same demand. This approach does not provide a clear answer regarding the effect of overall feedback inhibition on the robustness, stability, and transient time of the pathway. However, the generalized numerical method we have used does clarify the answers to these questions. On average, an unbranched pathway with control by overall feedback inhibition is less sensitive to perturbations in the values of the parameters that define the system. The difference in robustness can range from a few percent to fifty percent or more, depending on the length of the pathway and on the metabolite one considers. On average, overall feedback inhibition decreases the stability margins by a minimal amount (typically less than 5%). Finally, and again on average, stable systems with overall feedback inhibition respond faster to fluctuations in the metabolite concentrations. Taken together, these results show that control by overall feedback inhibition confers several functional advantages upon unbranched pathways. These advantages provide a rationale for the prevalence of this

Trichilia monadelpha Bark Extracts Inhibit Carrageenan-Induced ...

African Journals Online (AJOL)

The present study was undertaken to evaluate the anti-inflammatory properties of aqueous (TWE), alcoholic (TAE) and petroleum ether extract (TPEE) of T. ... The reference anti-inflammatory drugs (diclofenac and dexamethasone) inhibited the chick-carrageenan-induced footpad oedema, with maximal inhibitions of ...

Lactate dehydrogenase activity is inhibited by methylmalonate in vitro.

Science.gov (United States)

Saad, Laura O; Mirandola, Sandra R; Maciel, Evelise N; Castilho, Roger F

2006-04-01

Methylmalonic acidemia (MMAemia) is an inherited metabolic disorder of branched amino acid and odd-chain fatty acid metabolism, involving a defect in the conversion of methylmalonyl-coenzyme A to succinyl-coenzyme A. Systemic and neurological manifestations in this disease are thought to be associated with the accumulation of methylmalonate (MMA) in tissues and biological fluids with consequent impairment of energy metabolism and oxidative stress. In the present work we studied the effect of MMA and two other inhibitors of mitochondrial respiratory chain complex II (malonate and 3-nitropropionate) on the activity of lactate dehydrogenase (LDH) in tissue homogenates from adult rats. MMA potently inhibited LDH-catalyzed conversion of lactate to pyruvate in liver and brain homogenates as well as in a purified bovine heart LDH preparation. LDH was about one order of magnitude less sensitive to inhibition by MMA when catalyzing the conversion of pyruvate to lactate. Kinetic studies on the inhibition of brain LDH indicated that MMA inhibits this enzyme competitively with lactate as a substrate (K (i)=3.02+/-0.59 mM). Malonate and 3-nitropropionate also strongly inhibited LDH-catalyzed conversion of lactate to pyruvate in brain homogenates, while no inhibition was observed by succinate or propionate, when present in concentrations of up to 25 mM. We propose that inhibition of the lactate/pyruvate conversion by MMA contributes to lactate accumulation in blood, metabolic acidemia and inhibition of gluconeogenesis observed in patients with MMAemia. Moreover, the inhibition of LDH in the central nervous system may also impair the lactate shuttle between astrocytes and neurons, compromising neuronal energy metabolism.

Inhibition of human aromatase complex (CYP19) by antiepileptic drugs

DEFF Research Database (Denmark)

Jacobsen, Naja Wessel; Halling-Sørensen, Bent; Birkved, Franziska Maria A Kramer

2008-01-01

of 1.4-49.7 mM. Carbamazepine, gabapentin, primidone, topiramate and vigabatrin showed no inhibition. Additionally, binary drug combinations were tested to investigate if combination therapy could potentiate the aromatase inhibition. Additive inhibition was seen in combination experiments...... with valproate and phenobarbital. When adding carbamazepine to a range of valproate concentrations no additional inhibition was seen. The data for some of the AEDs show that side effects on steroid synthesis in humans due to inhibition of aromatase should be considered....

Homo economicus belief inhibits trust.

Directory of Open Access Journals (Sweden)

Ziqiang Xin

Full Text Available As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

Homo Economicus Belief Inhibits Trust

Science.gov (United States)

Xin, Ziqiang; Liu, Guofang

2013-01-01

As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners’ benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals’ homo economicus belief and inhibit their trust. It seems that people’s increasing homo economicus belief may serve as one cause of the worldwide decline of trust. PMID:24146907

Inhibition of PTEN and activation of Akt by menadione.

Science.gov (United States)

Yoshikawa, Kyoko; Nigorikawa, Kiyomi; Tsukamoto, Mariko; Tamura, Namiko; Hazeki, Kaoru; Hazeki, Osamu

2007-04-01

Menadione (vitamin K(3)) has been shown to activate Erk in several cell lines. This effect has been shown to be due to the activation of EGF receptors (EGFR) as a result of inhibition of some protein tyrosine phosphatases. In the present study, we examined the effects of menadione on Akt in Chinese hamster ovary cells. The phosphorylation of Akt by menadione was not inhibited by AG1478, an inhibitor of EGFR. Menadione inhibited the lipid phosphatase activity of PTEN in a cell-free system. In an intact cell system, menadione inhibited the effect of transfected PTEN on Akt. Thus, one mechanism of its action was considered the accelerated activation of Akt through inhibition of PTEN. This was not the sole mechanism responsible for the EGFR-independent activation of Akt, because menadione attenuated the rate of Akt dephosphorylation even in PTEN-null PC3 cells. The decelerated inactivation of Akt, probably through inhibition of some tyrosine phosphatases, was considered another mechanism of its action.

Inhibition and Adsorption impact of Leave Extracts of Cnidoscolus ...

African Journals Online (AJOL)

Corrosion inhibition in the presence of alokaloid and non alkaloid extracts of Cnidoscolus aconitifolius in 1M HCl was studied using the weight loss and hydrogen evolution techniques at 303, 313 and 333 K. The results obtained revealed that the inhibition efficiency decreased with increase in temperature. Inhibition ...

Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

International Nuclear Information System (INIS)

Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D.

1989-01-01

Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the α-glucosidase amyloglucosidase (50% inhibition at 5.8 μM), but it did not inhibit β-glucosidase, α- or β-mannosidase, or α- or β-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc 3 Man 7-9 (GlcNAc) 2 -oligosaccharides

Inhibition of poliovirus RNA synthesis by brefeldin A.

OpenAIRE

Maynell, L A; Kirkegaard, K; Klymkowsky, M W

1992-01-01

Brefeldin A (BFA), a fungal metabolite that blocks transport of newly synthesized proteins from the endoplasmic reticulum, was found to inhibit poliovirus replication 10(5)- to 10(6)-fold. BFA does not inhibit entry of poliovirus into the cell or translation of viral RNA. Poliovirus RNA synthesis, however, is completely inhibited by BFA. A specific class of membranous vesicles, with which the poliovirus replication complex is physically associated, is known to proliferate in poliovirus-infect...

Inhibition of urinary calculi -- a spectroscopic study

Science.gov (United States)

Manciu, Felicia; Govani, Jayesh; Durrer, William; Reza, Layra; Pinales, Luis

2008-10-01

Although a considerable number of investigations have already been undertaken and many causes such as life habits, metabolic disorders, and genetic factors have been noted as sources that accelerate calculi depositions and aggregations, there are still plenty of unanswered questions regarding efficient inhibition and treatment mechanisms. Thus, in an attempt to acquire more insights, we propose here a detailed scientific study of kidney stone formation and growth inhibition based on a traditional medicine approach with Rotula Aquatica Lour (RAL) herbal extracts. A simplified single diffusion gel growth technique was used for synthesizing the samples for the present study. The unexpected Zn presence in the sample with RAL inhibitor, as revealed by XPS measurements, explains the inhibition process and the dramatic reflectance of the incident light observed in the infrared transmission studies. Raman data demonstrate potential binding of the inhibitor with the oxygen of the kidney stone. Photoluminescence results corroborate to provide additional evidence of Zn-related inhibition.

Retrieval-Induced Inhibition in Short-Term Memory.

Science.gov (United States)

Kang, Min-Suk; Choi, Joongrul

2015-07-01

We used a visual illusion called motion repulsion as a model system for investigating competition between two mental representations. Subjects were asked to remember two random-dot-motion displays presented in sequence and then to report the motion directions for each. Remembered motion directions were shifted away from the actual motion directions, an effect similar to the motion repulsion observed during perception. More important, the item retrieved second showed greater repulsion than the item retrieved first. This suggests that earlier retrieval exerted greater inhibition on the other item being held in short-term memory. This retrieval-induced motion repulsion could be explained neither by reduced cognitive resources for maintaining short-term memory nor by continued inhibition between short-term memory representations. These results indicate that retrieval of memory representations inhibits other representations in short-term memory. We discuss mechanisms of retrieval-induced inhibition and their implications for the structure of memory. © The Author(s) 2015.

Neural correlates of central inhibition during physical fatigue.

Directory of Open Access Journals (Sweden)

Masaaki Tanaka

Full Text Available Central inhibition plays a pivotal role in determining physical performance during physical fatigue. Classical conditioning of central inhibition is believed to be associated with the pathophysiology of chronic fatigue. We tried to determine whether classical conditioning of central inhibition can really occur and to clarify the neural mechanisms of central inhibition related to classical conditioning during physical fatigue using magnetoencephalography (MEG. Eight right-handed volunteers participated in this study. We used metronome sounds as conditioned stimuli and maximum handgrip trials as unconditioned stimuli to cause central inhibition. Participants underwent MEG recording during imagery of maximum grips of the right hand guided by metronome sounds for 10 min. Thereafter, fatigue-inducing maximum handgrip trials were performed for 10 min; the metronome sounds were started 5 min after the beginning of the handgrip trials. The next day, neural activities during imagery of maximum grips of the right hand guided by metronome sounds were measured for 10 min. Levels of fatigue sensation and sympathetic nerve activity on the second day were significantly higher relative to those of the first day. Equivalent current dipoles (ECDs in the posterior cingulated cortex (PCC, with latencies of approximately 460 ms, were observed in all the participants on the second day, although ECDs were not identified in any of the participants on the first day. We demonstrated that classical conditioning of central inhibition can occur and that the PCC is involved in the neural substrates of central inhibition related to classical conditioning during physical fatigue.

Zinc-finger antiviral protein inhibits XMRV infection.

Directory of Open Access Journals (Sweden)

Xinlu Wang

Full Text Available BACKGROUND: The zinc-finger antiviral protein (ZAP is a host factor that specifically inhibits the replication of certain viruses, including Moloney murine leukemia virus (MoMLV, HIV-1, and certain alphaviruses and filoviruses. ZAP binds to specific viral mRNAs and recruits cellular mRNA degradation machinery to degrade the target RNA. The common features of ZAP-responsive RNA sequences remain elusive and thus whether a virus is susceptible to ZAP can only be determined experimentally. Xenotropic murine leukemia virus-related virus (XMRV is a recently identified γ-retrovirus that was originally thought to be involved in prostate cancer and chronic fatigue syndrome but recently proved to be a laboratory artefact. Nonetheless, XMRV as a new retrovirus has been extensively studied. Since XMRV and MoMLV share only 67.9% sequence identity in the 3'UTRs, which is the target sequence of ZAP in MoMLV, whether XMRV is susceptible to ZAP remains to be determined. FINDINGS: We constructed an XMRV-luc vector, in which the coding sequences of Gag-Pol and part of Env were replaced with luciferase-coding sequence. Overexpression of ZAP potently inhibited the expression of XMRV-luc in a ZAP expression-level-dependent manner, while downregulation of endogenous ZAP rendered cells more sensitive to infection. Furthermore, ZAP inhibited the spreading of replication-competent XMRV. Consistent with the previously reported mechanisms by which ZAP inhibits viral infection, ZAP significantly inhibited the accumulation of XMRV-luc mRNA in the cytoplasm. The ZAP-responsive element in XMRV mRNA was mapped to the 3'UTR. CONCLUSIONS: ZAP inhibits XMRV replication by preventing the accumulation of viral mRNA in the cytoplasm. Documentation of ZAP inhibiting XMRV helps to broaden the spectrum of ZAP's antiviral activity. Comparison of the target sequences of ZAP in XMRV and MoMLV helps to better understand the features of ZAP-responsive elements.

Inhibition of trypsin by condensed tannins and wine.

Science.gov (United States)

Gonçalves, Rui; Soares, Susana; Mateus, Nuno; de Freitas, Victor

2007-09-05

Phenolic compounds are abundant vegetable secondary metabolites in the human diet. The ability of procyanidin oligomers and wine polyphenols to inhibit trypsin activity was studied using a versatile and reliable in vitro method. The hydrolysis of the chromogenic substrate N-benzoyl-d,l-arginine-p-nitroanilide (BApNA) by trypsin was followed by spectrophotometry in the presence and absence of condensed tannins and wine. A clear relationship between the degree of polymerization of procyanidins and enzymatic inhibition was observed. Trypsin activity inhibition was also detected in several types of wine. In general, the inhibition increased with the concentration of phenolic compounds in wines. These results may be relevant when considering these compounds as antinutritional factors, thereby contributing to a reduced absorption of nutrients.

Transcriptome dynamics of the microRNA inhibition response

DEFF Research Database (Denmark)

Wen, Jiayu; Leucci, Elenora; Vendramin, Roberto

2015-01-01

We report a high-resolution time series study of transcriptome dynamics following antimiR-mediated inhibition of miR-9 in a Hodgkin lymphoma cell-line-the first such dynamic study of the microRNA inhibition response-revealing both general and specific aspects of the physiological response. We show...... validate the key observations with independent time series qPCR and we experimentally validate key predicted miR-9 targets. Methodologically, we developed sensitive functional data analytic predictive methods to analyse the weak response inherent in microRNA inhibition experiments. The methods...... of this study will be applicable to similar high-resolution time series transcriptome analyses and provides the context for more accurate experimental design and interpretation of future microRNA inhibition studies....

On inhibition of dental erosion.

Science.gov (United States)

Rölla, Gunnar; Jonski, Grazyna; Saxegaard, Erik

2013-11-01

To examine the erosion-inhibiting effect of different concentrations of hydrofluoric acid. Thirty-six human molars were individually treated with 10 ml of 0.1 M citric acid for 30 min (Etch 1), acid was collected and stored until analysis. The teeth were randomly divided into six groups and then individually treated with 10 ml of one of six dilutions (from 0.1-1%) of hydrofluoric acid. The teeth were then again treated with citric acid (Etch 2). The individual acid samples from Etch 1 and 2 were analyzed for calcium by flame atomic absorption spectroscopy and difference in calcium loss was calculated. The highest erosion inhibiting effect was obtained in groups with the highest concentrations of hydrofluoric acid, where the pH was lowest, below pKa of 3.17, thus the hydrofluoric acids being mainly in an undissociated state. Diluted hydrofluoric acid is present in aqueous solution of SnF2 and TiF4 (which are known to inhibit dental erosion): SnF2 + 3H2O = Sn(OH)2 + 2HF + H2O and TiF4 + 5H2O = Ti(OH)4 + 4HF + H2O. It is also known that pure, diluted hydrofluoric acid can inhibit dental erosion. Teeth treated with hydrofluoric acid are covered by a layer of CaF2-like mineral. This mineral is acid resistant at pH acid resistant mineral, initiated by tooth enamel treatment with hydrofluoric acid. Hydrofluoric acid is different in having fluoride as a conjugated base, which provides this acid with unique properties.

Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

Energy Technology Data Exchange (ETDEWEB)

Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D. (Univ. of Texas Health Science Center, San Antonio (USA))

1989-03-07

Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the {alpha}-glucosidase amyloglucosidase (50% inhibition at 5.8 {mu}M), but it did not inhibit {beta}-glucosidase, {alpha}- or {beta}-mannosidase, or {alpha}- or {beta}-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc{sub 3}Man{sub 7-9}(GlcNAc){sub 2}-oligosaccharides.

Silver-Palladium Surfaces Inhibit Biofilm Formation

DEFF Research Database (Denmark)

Chiang, Wen-Chi; Schroll, Casper; Hilbert, Lisbeth Rischel

2009-01-01

Undesired biofilm formation is a major concern in many areas. In the present study, we investigated biofilm-inhibiting properties of a silver-palladium surface that kills bacteria by generating microelectric fields and electrochemical redox processes. For evaluation of the biofilm inhibition...... efficacy and study of the biofilm inhibition mechanism, the silver-sensitive Escherichia coli J53 and the silver-resistant E. coli J53[pMG101] strains were used as model organisms, and batch and flow chamber setups were used as model systems. In the case of the silver-sensitive strain, the silver......-palladium surfaces killed the bacteria and prevented biofilm formation under conditions of low or high bacterial load. In the case of the silver-resistant strain, the silver-palladium surfaces killed surface-associated bacteria and prevented biofilm formation under conditions of low bacterial load, whereas under...

THE INHIBITION OF DEOXYRIBONUCLEASS I BY HYDEOXY-PIPHENYLS

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Gottesfeld, J.M.; Adams, N.H.; El-Badry, A.M.; Moses, V.; Calvin,M.

1970-09-01

DNA extracted with certain commercial brands of phenol is resistant to hydrolysis by the endonuclease DNAase I, while DNA extracted with other brands, or prepared by sodium chloride extraction, is susceptible to hydrolysis. The agent responsible for inhibition has been shown to be an oxidation product produced in some phenols. The inhibitor has been separated from other impurities in phenol by paper chromatography, and, by means of infrared and ultraviolet spectroscopy, it has been identified as o-hydroxybiphenyl. The kinetics of inhibition have been studied, and it was found that inhibition arises from direct action on the DNA rather than on the enzyme. Several hydroxybiphenyls and related compounds have been tested for inhibition, and a theory of molecular structure versus inhibitory effectiveness is suggested from this data. From studies on the chemical reversal of inhibition, as well as from ultraviolet spectral studies (in both absorption and circular dichroism), it appears that the mode of action of the inhibitors is hydrogen bonding to, and intercalation between, the basis of the nucleic acid.

Targeting fibroblast growth factor receptor signaling inhibits prostate cancer progression.

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Feng, Shu; Shao, Longjiang; Yu, Wendong; Gavine, Paul; Ittmann, Michael

2012-07-15

Extensive correlative studies in human prostate cancer as well as studies in vitro and in mouse models indicate that fibroblast growth factor receptor (FGFR) signaling plays an important role in prostate cancer progression. In this study, we used a probe compound for an FGFR inhibitor, which potently inhibits FGFR-1-3 and significantly inhibits FGFR-4. The purpose of this study is to determine whether targeting FGFR signaling from all four FGFRs will have in vitro activities consistent with inhibition of tumor progression and will inhibit tumor progression in vivo. Effects of AZ8010 on FGFR signaling and invasion were analyzed using immortalized normal prostate epithelial (PNT1a) cells and PNT1a overexpressing FGFR-1 or FGFR-4. The effect of AZ8010 on invasion and proliferation in vitro was also evaluated in prostate cancer cell lines. Finally, the impact of AZ8010 on tumor progression in vivo was evaluated using a VCaP xenograft model. AZ8010 completely inhibits FGFR-1 and significantly inhibits FGFR-4 signaling at 100 nmol/L, which is an achievable in vivo concentration. This results in marked inhibition of extracellular signal-regulated kinase (ERK) phosphorylation and invasion in PNT1a cells expressing FGFR-1 and FGFR-4 and all prostate cancer cell lines tested. Treatment in vivo completely inhibited VCaP tumor growth and significantly inhibited angiogenesis and proliferation and increased cell death in treated tumors. This was associated with marked inhibition of ERK phosphorylation in treated tumors. Targeting FGFR signaling is a promising new approach to treating aggressive prostate cancer.

Sex differences in emotional contexts modulation on response inhibition.

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Ramos-Loyo, Julieta; Angulo-Chavira, Armando; Llamas-Alonso, Luis A; González-Garrido, Andrés A

2016-10-01

The aim of the present study was to explore sex differences in the effects that emotional contexts exert on the temporal course of response inhibition using event-related potentials (ERP). Participants performed a Go-NoGo response inhibition task under 3 context conditions: with 1) neutral background stimuli, and 2) pleasant, and 3) unpleasant emotional contexts. No sex differences were found in relation to accuracy. Women showed higher N2NoGo amplitudes than men in both emotional contexts; whereas during inhibition men tended to show higher P3NoGo amplitudes than women in the unpleasant context. Both groups experienced a relevant effect of the presence of the unpleasant context during inhibition processing, as shown by the enhancement of the N2NoGo amplitudes in frontal regions compared to results from the neutral and pleasant conditions. In addition, women showed differences between the pleasant and unpleasant contexts, with the latter inducing higher amplitude values. Only in men did inhibition accuracy correlate with higher N2NoGo and lower P3NoGo amplitudes in the emotional context conditions. These findings suggest that when an inhibition task is performed in an emotionally-neutral background context no sex differences are observed in either accuracy or ERP components. However, when the emotional context was introduced -especially the unpleasant one- some gender differences did become evident. The higher N2NoGo amplitude at the presence of the unpleasant context may reflect an effect on attention and conflict monitoring. In addition, results suggest that during earlier processing stages, women invested more resources to process inhibition than men. Furthermore, men who invested more neural resources during earlier stages showed better response inhibition than those who did it during later processing stages, more closely-related to cognitive and motor inhibition processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Inhibition of the Components from Shengmai Injection towards UDP-Glucuronosyltransferase

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Li-Peng Jiang

2014-01-01

Full Text Available The mechanism of shengmai injection- (SMI- related drug-drug interaction remains unclear. Evaluation of the inhibition potential of SMI’s ingredients towards UDP-glucuronosyltransferases (UGTs activity will provide a new insight to understand SMI-related drug-drug interaction. In vitro incubation system to model UGT reaction was used. Recombinant UGT isoforms-catalyzed 4-methylumbelliferone (4-MU glucuronidation and UGT1A4-catalyzed trifluoperazine (TFP glucuronidation reactions were employed to phenotype the inhibition profile of maidong’s components towards the activity of UGT isoforms. Different inhibition potential of maidong’s components towards various UGT isoforms was observed. Based on the inhibition kinetic investigation results, ophiopogonin D (OD noncompetitively inhibited UGT1A6 and competitively inhibited UGT1A8, ophiopogonin D′ (OD′ noncompetitively inhibited UGT1A6 and UGT1A10, and ruscorectal (RU exhibited competitive inhibition towards UGT1A4. The inhibition kinetic parameters were calculated to be 20.6, 40.1, 5.3, 9.0, and 0.02 μM, respectively. In combination with our previous results obtained for the inhibition of UGT isoforms by ginsenosides and wuweizi components, the important SMI ingredients exhibiting strong inhibition towards UGT isoforms were highlighted. All the results obtained in the present study provide a new insight to understand SMI-related drug-drug interaction.

Hili Inhibits HIV Replication in Activated T Cells.

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Peterlin, B Matija; Liu, Pingyang; Wang, Xiaoyun; Cary, Daniele; Shao, Wei; Leoz, Marie; Hong, Tian; Pan, Tao; Fujinaga, Koh

2017-06-01

P-element-induced wimpy-like (Piwil) proteins restrict the replication of mobile genetic elements in the germ line. They are also expressed in many transformed cell lines. In this study, we discovered that the human Piwil 2 (Hili) protein can also inhibit HIV replication, especially in activated CD4 + T cells that are the preferred target cells for this virus in the infected host. Although resting cells did not express Hili, its expression was rapidly induced following T cell activation. In these cells and transformed cell lines, depletion of Hili increased levels of viral proteins and new viral particles. Further studies revealed that Hili binds to tRNA. Some of the tRNAs represent rare tRNA species, whose codons are overrepresented in the viral genome. Targeting tRNA Arg (UCU) with an antisense oligonucleotide replicated effects of Hili and also inhibited HIV replication. Finally, Hili also inhibited the retrotransposition of the endogenous intracysternal A particle (IAP) by a similar mechanism. Thus, Hili joins a list of host proteins that inhibit the replication of HIV and other mobile genetic elements. IMPORTANCE Piwil proteins inhibit the movement of mobile genetic elements in the germ line. In their absence, sperm does not form and male mice are sterile. This inhibition is thought to occur via small Piwi-interacting RNAs (piRNAs). However, in some species and in human somatic cells, Piwil proteins bind primarily to tRNA. In this report, we demonstrate that human Piwil proteins, especially Hili, not only bind to select tRNA species, including rare tRNAs, but also inhibit HIV replication. Importantly, T cell activation induces the expression of Hili in CD4 + T cells. Since Hili also inhibited the movement of an endogenous retrovirus (IAP), our finding shed new light on this intracellular resistance to exogenous and endogenous retroviruses as well as other mobile genetic elements. Copyright © 2017 American Society for Microbiology.

Interactions between tetrathiafulvalene units in dimeric structures – the influence of cyclic cores

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Huixin Jiang

2015-06-01

Full Text Available A selection of cyclic and acyclic acetylenic scaffolds bearing two tetrathiafulvalene (TTF units was prepared by different metal-catalyzed coupling reactions. The bridge separating the two TTF units was systematically changed from linearly conjugated ethyne, butadiyne and tetraethynylethene (trans-substituted units to a cross-conjugated tetraethynylethene unit, placed in either acyclic or cyclic arrangements. The cyclic structures correspond to so-called radiaannulenes having both endo- and exocyclic double bonds. Interactions between two redox-active TTF units in these molecules were investigated by cyclic voltammetry, UV–vis–NIR and EPR absorption spectroscopical methods of the electrochemically generated oxidized species. The electron-accepting properties of the acetylenic cores were also investigated electrochemically.

The Reduction of Directed Cyclic Graph for Task Assignment Problem

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Ariffin W.N.M.

2018-01-01

Full Text Available In this paper, a directed cyclic graph (DCG is proposed as the task graph. It is undesirable and impossible to complete the task according to the constraints if the cycle exists. Therefore, an effort should be done in order to eliminate the cycle to obtain a directed acyclic graph (DAG, so that the minimum amount of time required for the entire task can be found. The technique of reducing the complexity of the directed cyclic graph to a directed acyclic graph by reversing the orientation of the path is the main contribution of this study. The algorithm was coded using Java programming and consistently produced good assignment and task schedule.

Chirality Influence of Zaltoprofen Towards UDP-Glucuronosyltransferases (UGTs) Inhibition Potential.

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Jia, Lin; Hu, Cuimin; Wang, Haina; Liu, Yongzhe; Liu, Xin; Zhang, Yan-Yan; Li, Wei; Wang, Li-Xuan; Cao, Yun-Feng; Fang, Zhong-Ze

2015-06-01

Zaltoprofen (ZLT) is a nonsteroidal antiinflammation drug, and has been clinically employed to treat rheumatoid arthritis, osteoarthritis, and other chronic inflammatory pain conditions. The present study aims to investigate the chirality influence of zaltoprofen towards the inhibition potential towards UDP-glucuronosyltransferases (UGTs) isoforms. In vitro a recombinant UGT isoforms-catalyzed 4-methylumbelliferone (4-MU) glucuronidation incubation system was employed to investigate the inhibition of (R)-zaltoprofen and (S)-zaltoprofen towards UGT isoforms. The inhibition difference capability was observed for the inhibition of (R)-zaltoprofen and (S)-zaltoprofen towards UGT1A8 and UGT2B7, but not for other tested UGT isoforms. (R)-zaltoprofen exhibited noncompetitive inhibition towards UGT1A8 and competitive inhibition towards UGT2B7. The inhibition kinetic parameters were calculated to be 35.3 μM and 19.2 μM for UGT1A8 and UGT2B7. (R)-zaltoprofen and (S)-zaltoprofen exhibited a different inhibition type towards UGT1A7. Based on the reported maximum plasma concentration of (R)-zaltoprofen in vivo, a high drug-drug interaction between (R)-zaltoprofen and the drugs mainly undergoing UGT1A7, UGT1A8, and UGT2B7-catalyzed glucuronidation was indicated. © 2015 Wiley Periodicals, Inc.

Cortical organization of inhibition-related functions and modulation by psychopathology.

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Warren, Stacie L; Crocker, Laura D; Spielberg, Jeffery M; Engels, Anna S; Banich, Marie T; Sutton, Bradley P; Miller, Gregory A; Heller, Wendy

2013-01-01

Individual differences in inhibition-related functions have been implicated as risk factors for a broad range of psychopathology, including anxiety and depression. Delineating neural mechanisms of distinct inhibition-related functions may clarify their role in the development and maintenance of psychopathology. The present study tested the hypothesis that activity in common and distinct brain regions would be associated with an ecologically sensitive, self-report measure of inhibition and a laboratory performance measure of prepotent response inhibition. Results indicated that sub-regions of DLPFC distinguished measures of inhibition, whereas left inferior frontal gyrus and bilateral inferior parietal cortex were associated with both types of inhibition. Additionally, co-occurring anxiety and depression modulated neural activity in select brain regions associated with response inhibition. Results imply that specific combinations of anxiety and depression dimensions are associated with failure to implement top-down attentional control as reflected in inefficient recruitment of posterior DLPFC and increased activation in regions associated with threat (MTG) and worry (BA10). Present findings elucidate possible neural mechanisms of interference that could help explain executive control deficits in psychopathology.

Cortical organization of inhibition-related functions and modulation by psychopathology

Directory of Open Access Journals (Sweden)

Stacie L. Warren

2013-06-01

Full Text Available Individual differences in inhibition-related functions have been implicated as risk factors for a broad range of psychopathology, including anxiety and depression. Delineating neural mechanisms of distinct inhibition-related functions may clarify their role in the development and maintenance of psychopathology. The present study tested the hypothesis that activity in common and distinct brain regions would be associated with an ecologically sensitive, self-report measure of inhibition and a laboratory performance measure of prepotent response inhibition. Results indicated that sub-regions of DLPFC distinguished measures of inhibition, whereas left inferior frontal gyrus and bilateral inferior parietal cortex were associated with both types of inhibition. Additionally, co-occurring anxiety and depression modulated neural activity in select brain regions associated with response inhibition. Results imply that specific combinations of anxiety and depression dimensions are associated with failure to implement top-down attentional control as reflected in inefficient recruitment of posterior DLPFC and increased activation in regions associated with threat (MTG and worry (BA10. Present findings elucidate possible neural mechanisms of interference that could help explain executive control deficits in psychopathology.

A specific bioassay for the inhibition of flowering.

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Blake, J

1972-06-01

A bioassay for the inhibition of flowering involving the in vitro culture of excised, partially-induced, apices of Viscaria candida is described. This bioassay has been used to detect flowering inhibition in extracts from Kalanchoe blossfeldiana.

Influence of dominance status on adrenal activity and ovarian cyclicity status in captive African elephants.

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Proctor, Christine M; Freeman, Elizabeth W; Brown, Janine L

2010-01-01

The North American African (Loxodonta africana) elephant population is not self-sustaining, in part because of a high rate of abnormal ovarian activity. About 12% of adult females exhibit irregular cycles and 31% do not cycle at all. Our earlier work revealed a relationship between dominance status and ovarian acyclicity, with dominant females being more likely to not cycle normally. One theory is that dominant females may be expending more energy to maintaining peace within the captive herd than for supporting reproduction. The goal of this study was to determine if there was a relationship among dominance status, serum cortisol concentrations, and ovarian acyclicity. We hypothesized that adrenal glucocorticoid activity would be increased in dominant, noncycling elephants as compared with subdominant individuals. Blood samples were collected weekly over a 2-year period in 81 females of known dominance and cyclicity status, and analyzed for cortisol. Based on a path analysis model (Reticular Action Model Or Near Approximation [RAMONA]), noncycling, dominant African elephant females did not have higher mean serum cortisol concentrations, or exhibit more variability (i.e., coefficient of variation, standard deviation) in cortisol secretion. This study suggests that alterations in adrenal activity are not related to dominance status nor contribute directly to acyclicity in captive African elephants.

Inhibition: Mental Control Process or Mental Resource?

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Im-Bolter, Nancie; Johnson, Janice; Ling, Daphne; Pascual-Leone, Juan

2015-01-01

The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among…

Differences between endogenous and exogenous emotion inhibition in the human brain.

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Kühn, Simone; Haggard, Patrick; Brass, Marcel

2014-05-01

The regulation of emotions is an integral part of our mental health. It has only recently been investigated using brain imaging techniques. In most studies, participants are instructed by a cue to inhibit a specific emotional reaction. The aim of the present study was to investigate the alternative situation where a person decides to inhibit an emotion as an act of endogenous self-control. Healthy participants viewed highly arousing pictures with negative valence. In the endogenous condition, participants could freely choose on each trial to inhibit or feel the emotions elicited by the picture. In an exogenous condition, a visual cue instructed them to either feel or inhibit the emotion elicited by the picture. Participants' subjective ratings of intensity of experienced emotion showed an interaction effect between source of control (endogenous/exogenous) and feel/inhibit based on a stronger modulation between feel and inhibition for the endogenous compared to the exogenous condition. Endogenous inhibition of emotions was associated with dorso-medial prefrontal cortex activation, whereas exogenous inhibition was found associated with lateral prefrontal cortex activation. Thus, the brain regions for both endogenous and exogenous inhibition of emotion are highly similar to those for inhibition of motor actions in Brass and Haggard (J Neurosci 27:9141-9145, 2007), Kühn et al. (Hum Brain Mapp 30:2834-2843, 2009). Functional connectivity analyses showed that dorsofrontomedial cortex exerts greater control onto pre-supplementary motor area during endogenous inhibition compared to endogenous feel. This functional dissociation between an endogenous, fronto-medial and an exogenous, fronto-lateral inhibition centre has important implications for our understanding of emotion regulation in health and psychopathology.

Mechanisms of caffeine-induced inhibition of UVB carcinogenesis

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Allan H Conney

2013-06-01

Full Text Available Sunlight-induced nonmelanoma skin cancer is the most prevalent cancer in the United States with more than 2 million cases per year. Several studies have shown an inhibitory effect of caffeine administration on UVB-induced skin cancer in mice, and these studies are paralleled by epidemiology studies that indicate an inhibitory effect of coffee drinking on nonmelanoma skin cancer in humans. Strikingly, decaffeinated coffee consumption had no such inhibitory effect.Mechanism studies indicate that caffeine has a sunscreen effect that inhibits UVB-induced formation of thymine dimers and sunburn lesions in the epidermis of mice. In addition, caffeine administration has a biological effect that enhances UVB-induced apoptosis thereby enhancing the elimination of damaged precancerous cells, and caffeine administration also enhances apoptosis in tumors. Caffeine administration enhances UVB-induced apoptosis by p53-dependent and p53-independent mechanisms. Exploration of the p53-independent effect indicated that caffeine administration enhanced UVB-induced apoptosis by inhibiting the UVB-induced increase in ATR-mediated formation of phospho-Chk1 (Ser345 and abolishing the UVB-induced decrease in cyclin B1 which resulted in caffeine-induced premature and lethal mitosis in mouse skin. In studies with cultured primary human keratinocytes, inhibition of ATR with siRNA against ATR inhibited Chk1 phosphorylation and enhanced UVB-induced apoptosis. Transgenic mice with decreased epidermal ATR function that were irradiated chronically with UVB had 69% fewer tumors at the end of the study compared with irradiated littermate controls with normal ATR function. These results, which indicate that genetic inhibition of ATR (like pharmacologic inhibition of ATR via caffeine inhibits UVB-induced carcinogenesis and supports the concept that ATR-mediated phosphorylation of Chk1 is an important target for caffeine’s inhibitory effect on UVB-induced carcinogenesis.

Acrolein in cigarette smoke inhibits T-cell responses.

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Lambert, Cherie; McCue, Jesica; Portas, Mary; Ouyang, Yanli; Li, JiMei; Rosano, Thomas G; Lazis, Alexander; Freed, Brian M

2005-10-01

Cigarette smoking inhibits T-cell responses in the lungs, but the immunosuppressive compounds have not been fully identified. Cigarette smoke extracts inhibit IL-2, IFN-gamma, and TNF-alpha production in stimulated lymphocytes obtained from peripheral blood, even when the extracts were diluted 100-fold to 1000-fold. The objective of these studies was to identify the immunosuppressive compounds found in cigarette smoke. Gas chromatography/mass spectroscopy and HPLC were used to identify and quantitate volatile compounds found in cigarette smoke extracts. Bioactivity was measured by viability and production of cytokine mRNA and protein levels in treated human lymphocytes. The vapor phase of the cigarette smoke extract inhibited cytokine production, indicating that the immunosuppressive compounds were volatile. Among the volatile compounds identified in cigarette smoke extracts, only the alpha,beta-unsaturated aldehydes, acrolein (inhibitory concentration of 50% [IC50] = 3 micromol/L) and crotonaldehyde (IC50 = 6 micromol/L), exhibited significant inhibition of cytokine production. Although the levels of aldehydes varied 10-fold between high-tar (Camel) and ultralow-tar (Carlton) extracts, even ultralow-tar cigarettes produced sufficient levels of acrolein (34 micromol/L) to suppress cytokine production by >95%. We determined that the cigarette smoke extract inhibited transcription of cytokine genes. The inhibitory effects of acrolein could be blocked with the thiol compound N-acetylcysteine. The vapor phase from cigarette smoke extracts potently suppresses cytokine production. The compound responsible for this inhibition appears to be acrolein.

Nickel Inhibits Mitochondrial Fatty Acid Oxidation

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Uppala, Radha; McKinney, Richard W.; Brant, Kelly A.; Fabisiak, James P.; Goetzman, Eric S.

2015-01-01

Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation—the pathway by which fatty acids are catabolized for energy—in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with L-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 hr), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis. PMID:26051273

IGF-1 receptor inhibition by picropodophyllin in medulloblastoma

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Ohshima-Hosoyama, Sachiko; Hosoyama, Tohru; Nelon, Laura D. [Greehey Children' s Cancer Research Institute, University of Texas Health Science Center, San Antonio, TX 78229 (United States); Keller, Charles, E-mail: keller@ohsu.edu [Greehey Children' s Cancer Research Institute, University of Texas Health Science Center, San Antonio, TX 78229 (United States); Department of Pediatrics, University of Texas Health Science Center, San Antonio, TX 78229 (United States); Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229 (United States)

2010-09-03

Research highlights: {yields} Igf1r is overexpressed and activated in a Sonic Hedgehog driven model of medulloblastoma. {yields} Picropodophyllin targets and abrogates IGF signaling in medulloblastoma. {yields} Picropodophyllin inhibits medulloblastoma tumor cell growth by induction of apoptosis. -- Abstract: The insulin-like growth factor-1 receptor (Igf1r) is a multifunctional membrane-associated tyrosine kinase associated with regulation of transformation, proliferation, differentiation and apoptosis. Increased IGF pathway activity has been reported in human and murine medulloblastoma. Tumors from our genetically-engineered medulloblastoma mouse model over-express Igf1r, and thus this mouse model is a good platform with which to study the role of Igf1r in tumor progression. We hypothesize that inhibition of IGF pathway in medulloblastoma can slow or inhibit tumor growth and metastasis. To test our hypothesis, we tested the role of IGF in tumor growth in vitro by treatment with the tyrosine kinase small molecule inhibitor, picropodophyllin (PPP), which strongly inhibits the IGF pathway. Our results demonstrate that PPP-mediated downregulation of the IGF pathway inhibits mouse tumor cell growth and induces apoptotic cell death in vitro in primary medulloblastoma cultures that are most reflective of tumor cell behavior in vivo.

IGF-1 receptor inhibition by picropodophyllin in medulloblastoma

International Nuclear Information System (INIS)

Ohshima-Hosoyama, Sachiko; Hosoyama, Tohru; Nelon, Laura D.; Keller, Charles

2010-01-01

Research highlights: → Igf1r is overexpressed and activated in a Sonic Hedgehog driven model of medulloblastoma. → Picropodophyllin targets and abrogates IGF signaling in medulloblastoma. → Picropodophyllin inhibits medulloblastoma tumor cell growth by induction of apoptosis. -- Abstract: The insulin-like growth factor-1 receptor (Igf1r) is a multifunctional membrane-associated tyrosine kinase associated with regulation of transformation, proliferation, differentiation and apoptosis. Increased IGF pathway activity has been reported in human and murine medulloblastoma. Tumors from our genetically-engineered medulloblastoma mouse model over-express Igf1r, and thus this mouse model is a good platform with which to study the role of Igf1r in tumor progression. We hypothesize that inhibition of IGF pathway in medulloblastoma can slow or inhibit tumor growth and metastasis. To test our hypothesis, we tested the role of IGF in tumor growth in vitro by treatment with the tyrosine kinase small molecule inhibitor, picropodophyllin (PPP), which strongly inhibits the IGF pathway. Our results demonstrate that PPP-mediated downregulation of the IGF pathway inhibits mouse tumor cell growth and induces apoptotic cell death in vitro in primary medulloblastoma cultures that are most reflective of tumor cell behavior in vivo.

Palmitoylethanolamide Inhibits Glutamate Release in Rat Cerebrocortical Nerve Terminals

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Tzu-Yu Lin

2015-03-01

Full Text Available The effect of palmitoylethanolamide (PEA, an endogenous fatty acid amide displaying neuroprotective actions, on glutamate release from rat cerebrocortical nerve terminals (synaptosomes was investigated. PEA inhibited the Ca2+-dependent release of glutamate, which was triggered by exposing synaptosomes to the potassium channel blocker 4-aminopyridine. This release inhibition was concentration dependent, associated with a reduction in cytosolic Ca2+ concentration, and not due to a change in synaptosomal membrane potential. The glutamate release-inhibiting effect of PEA was prevented by the Cav2.1 (P/Q-type channel blocker ω-agatoxin IVA or the protein kinase A inhibitor H89, not affected by the intracellular Ca2+ release inhibitors dantrolene and CGP37157, and partially antagonized by the cannabinoid CB1 receptor antagonist AM281. Based on these results, we suggest that PEA exerts its presynaptic inhibition, likely through a reduction in the Ca2+ influx mediated by Cav2.1 (P/Q-type channels, thereby inhibiting the release of glutamate from rat cortical nerve terminals. This release inhibition might be linked to the activation of presynaptic cannabinoid CB1 receptors and the suppression of the protein kinase A pathway.