Tetra-amelia and splenogonadal fusion in Roberts syndrome

Energy Technology Data Exchange (ETDEWEB)

Ravel, T.J.L. de; Seftel, M.D.; Wright, C.A. [Univ. of the Witwatersrand, Johannesburg (South Africa)

1997-01-20

Roberts-SC phocomelia syndrome comprises limb deficiencies of variable severity, facial clefts, and other anomalies. Tetra-amelia may also be associated with facial clefts and similar anomalies. We report on a female infant with severe tetra-amelia, micrognathia, cleft palate, splenogonadal fusion, and premature centromere separation. We propose that this represents the severe expression of the Roberts-SC phocomelia syndrome. 18 refs., 6 figs.

Tetra-phocomelia: a rarest of rare case.

Science.gov (United States)

Shukla, Anil Kumar; Sanjay, S C; Krishna, L; Krishnappa, N

2015-03-01

We present a rarest of rare case of Tetra-Phocomelia evaluated by antenatal Ultrasonography. It is a condition seen in 0.62 per 100,000 live births. An ultrasonogram was done at 18 wk of pregnancy to assess the fetus and after termination gross specimen was evaluated and X-ray infantograms were done to confirm the findings. The case showed classic Tetra-Phocomelia with limbs like flippers of a seal. Our findings make it rarest of rare as only few cases have been so far reported.

Robustness of a TETRA base station receiver against intentional EMI

NARCIS (Netherlands)

van de Beek, G.S.; Leferink, Frank Bernardus Johannes

2015-01-01

Terrestrial trunked radio (TETRA) is a digital radio standard that was developed to meet the needs of professional mobile radio systems. TETRA is vulnerable to intentional electromagnetic interference (EMI) because of the wireless link. The EMI can easily be front door coupled to the base station

Nanostructurization effects in PVP-stabilized tetra-arsenic tetra-sulfide As{sub 4}S{sub 4} nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Shpotyuk, O., E-mail: olehshpotyuk@yahoo.com [Institute of Physics of Jan Dlugosz University in Czestochowa, 13/15, Al. Armii Krajowej, Czestochowa, 42200 (Poland); Vlokh Institute of Physical Optics, 23, Dragomanov Str., Lviv, 79005 (Ukraine); Scientific Research Company “Carat”, 202, Stryjska Str., 79031, Lviv (Ukraine); Bujňáková, Z.; Baláž, P. [Institute of Geotechnics of Slovak Academy of Sciences, 45, Watsonova Str., Košice, 04001 (Slovakia); Ingram, A. [Opole University of Technology, 75, Ozimska Str., Opole, 45370 (Poland); Demchenko, P. [Ivan Franko National University of Lviv, 1, Universytetska Str., 79000 Lviv (Ukraine); Kovalskiy, A. [Department of Physics & Astronomy, Austin Peay State University, Clarksville, TN, 37044 (United States); Vlcek, M. [Department of General and Inorganic Chemistry, Faculty of Chemistry, University of Pardubice, 532 10, Pardubice (Czech Republic); Shpotyuk, Ya. [Ivan Franko National University of Lviv, 1, Universytetska Str., 79000 Lviv (Ukraine); Centre for Innovation and Transfer of Natural Sciences and Engineering Knowledge, 1, Pigonia Str., 35310, Rzeszow (Poland); Cebulski, J.; Dziedzic, A. [Centre for Innovation and Transfer of Natural Sciences and Engineering Knowledge, 1, Pigonia Str., 35310, Rzeszow (Poland)

2017-01-15

Nanostructurization in three types of tetra-arsenic tetra-sulfide As{sub 4}S{sub 4} polymorphs composed by (1) preferential β-As{sub 4}S{sub 4}, (2) realgar α-As{sub 4}S{sub 4} and (3) admixture of As{sub 4}S{sub 4} in the form of β-realgar, pararealgar and intermediate χ-phase subjected to mechanochemical ball milling in a water solution of polyvinylpyrrolidone (PVP) are characterized with multiexperimental structure-sensitive probes. Void structure of pelletized As{sub 4}S{sub 4}-PVP nanocomposites is probed by positron annihilation lifetime spectroscopy complemented with atomic-sensitive techniques such as X-ray powder diffraction, Raman scattering and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Appearance of arsenolite As{sub 2}O{sub 3} crystallites is character for all As{sub 4}S{sub 4} polymorphs affected by wet milling. Positron annihilation lifetime data considered in terms of substitution positron-positronium trapping confirm complicated nature of nanocomposites. Modified x3-x2-coupling decomposition algorithm developed in addition to unconstrained x3-term fitting procedure is applied to parameterize annihilation channels in these nanocomposites. Interfacial free-volume voids between neighboring nanoparticles in PVP environment are defined as most favorable trapping sites, they being rather loosely composed by As{sub 4}S{sub 4} crystallites in full respect to variety of crystallographic polymorphs used for milling. Detected annihilation channels are ascribed preferentially to intrinsic free-volume voids insensitive to trapping states at the surface of oxidized nanocomposites. - Highlights: • PVP-stabilized tetra-arsenic tetra-sulfide nanocomposites prepared by wet milling. • As{sub 4}S{sub 4}-PVP composites by complementary atomic-specific and deficient structure probes. • Surface oxidation due to crystalline arsenolite As{sub 2}O{sub 3} under wet milling. • Free-volume structure of PVP-stabilized As{sub 4}S{sub 4

Kinetic parameters and TL mechanism in cadmium tetra borate phosphor

International Nuclear Information System (INIS)

Annalakshmi, O.; Jose, M.T.; Sridevi, J.; Venkatraman, B.; Amarendra, G.; Mandal, A.B.

2014-01-01

Polycrystalline powder samples of cadmium tetra borate were synthesized by a simple solid state sintering technique and gamma irradiated sample showed a simple Thermoluminescence (TL) glow peak around 460 K. The TL kinetic parameters of gamma irradiated phosphor were determined by initial rise (IR), isothermal decay (ID), peak shape (PS), variable heating rate (VHR) and glow curve de-convolution method. The kinetic parameters such as activation energy (E), frequency factor (s) and order of kinetics (b) were calculated by IR, ID, PS and VHR methods are in the order of ∼1.05 eV, 10 9 –10 12 s −1 and 1.58, respectively. From the results of TL and PL emission studies carried out on the phosphor revealed that the defect centers related to TL is different from that for PL. EPR measurements were carried out to identify the defect centers formed in cadmium tetra borate phosphor on gamma irradiation. Based on EPR studies the mechanism for TL process in cadmium tetra borate is proposed in this paper -- Highlights: • Polycrystalline powder samples of undoped cadmium tetra borate synthesized. • Cadmium tetra borate phosphor exhibits a dosimetric peak at 458 K. • Kinetic parameters of the trap responsible for TL evaluated. • TL mechanism is proposed from TL to EPR correlation studies

Kinetic parameters and TL mechanism in cadmium tetra borate phosphor

Energy Technology Data Exchange (ETDEWEB)

Annalakshmi, O. [Radiological Safety Division, Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Jose, M.T., E-mail: mtj@igcar.gov.in [Radiological Safety Division, Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Sridevi, J. [Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600 020, Tamilnadhu (India); Venkatraman, B. [Radiological Safety Division, Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Amarendra, G. [Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Mandal, A.B. [Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600 020, Tamilnadhu (India)

2014-03-15

Polycrystalline powder samples of cadmium tetra borate were synthesized by a simple solid state sintering technique and gamma irradiated sample showed a simple Thermoluminescence (TL) glow peak around 460 K. The TL kinetic parameters of gamma irradiated phosphor were determined by initial rise (IR), isothermal decay (ID), peak shape (PS), variable heating rate (VHR) and glow curve de-convolution method. The kinetic parameters such as activation energy (E), frequency factor (s) and order of kinetics (b) were calculated by IR, ID, PS and VHR methods are in the order of ∼1.05 eV, 10{sup 9}–10{sup 12} s{sup −1} and 1.58, respectively. From the results of TL and PL emission studies carried out on the phosphor revealed that the defect centers related to TL is different from that for PL. EPR measurements were carried out to identify the defect centers formed in cadmium tetra borate phosphor on gamma irradiation. Based on EPR studies the mechanism for TL process in cadmium tetra borate is proposed in this paper -- Highlights: • Polycrystalline powder samples of undoped cadmium tetra borate synthesized. • Cadmium tetra borate phosphor exhibits a dosimetric peak at 458 K. • Kinetic parameters of the trap responsible for TL evaluated. • TL mechanism is proposed from TL to EPR correlation studies.

Method for predicting peptide detection in mass spectrometry

Science.gov (United States)

Kangas, Lars [West Richland, WA; Smith, Richard D [Richland, WA; Petritis, Konstantinos [Richland, WA

2010-07-13

A method of predicting whether a peptide present in a biological sample will be detected by analysis with a mass spectrometer. The method uses at least one mass spectrometer to perform repeated analysis of a sample containing peptides from proteins with known amino acids. The method then generates a data set of peptides identified as contained within the sample by the repeated analysis. The method then calculates the probability that a specific peptide in the data set was detected in the repeated analysis. The method then creates a plurality of vectors, where each vector has a plurality of dimensions, and each dimension represents a property of one or more of the amino acids present in each peptide and adjacent peptides in the data set. Using these vectors, the method then generates an algorithm from the plurality of vectors and the calculated probabilities that specific peptides in the data set were detected in the repeated analysis. The algorithm is thus capable of calculating the probability that a hypothetical peptide represented as a vector will be detected by a mass spectrometry based proteomic platform, given that the peptide is present in a sample introduced into a mass spectrometer.

Repeatability and Reproducibility in Proteomic Identifications by Liquid Chromatography—Tandem Mass Spectrometry

Science.gov (United States)

Tabb, David L.; Vega-Montoto, Lorenzo; Rudnick, Paul A.; Variyath, Asokan Mulayath; Ham, Amy-Joan L.; Bunk, David M.; Kilpatrick, Lisa E.; Billheimer, Dean D.; Blackman, Ronald K.; Cardasis, Helene L.; Carr, Steven A.; Clauser, Karl R.; Jaffe, Jacob D.; Kowalski, Kevin A.; Neubert, Thomas A.; Regnier, Fred E.; Schilling, Birgit; Tegeler, Tony J.; Wang, Mu; Wang, Pei; Whiteaker, Jeffrey R.; Zimmerman, Lisa J.; Fisher, Susan J.; Gibson, Bradford W.; Kinsinger, Christopher R.; Mesri, Mehdi; Rodriguez, Henry; Stein, Steven E.; Tempst, Paul; Paulovich, Amanda G.; Liebler, Daniel C.; Spiegelman, Cliff

2009-01-01

The complexity of proteomic instrumentation for LC-MS/MS introduces many possible sources of variability. Data-dependent sampling of peptides constitutes a stochastic element at the heart of discovery proteomics. Although this variation impacts the identification of peptides, proteomic identifications are far from completely random. In this study, we analyzed interlaboratory data sets from the NCI Clinical Proteomic Technology Assessment for Cancer to examine repeatability and reproducibility in peptide and protein identifications. Included data spanned 144 LC-MS/MS experiments on four Thermo LTQ and four Orbitrap instruments. Samples included yeast lysate, the NCI-20 defined dynamic range protein mix, and the Sigma UPS 1 defined equimolar protein mix. Some of our findings reinforced conventional wisdom, such as repeatability and reproducibility being higher for proteins than for peptides. Most lessons from the data, however, were more subtle. Orbitraps proved capable of higher repeatability and reproducibility, but aberrant performance occasionally erased these gains. Even the simplest protein digestions yielded more peptide ions than LC-MS/MS could identify during a single experiment. We observed that peptide lists from pairs of technical replicates overlapped by 35–60%, giving a range for peptide-level repeatability in these experiments. Sample complexity did not appear to affect peptide identification repeatability, even as numbers of identified spectra changed by an order of magnitude. Statistical analysis of protein spectral counts revealed greater stability across technical replicates for Orbitraps, making them superior to LTQ instruments for biomarker candidate discovery. The most repeatable peptides were those corresponding to conventional tryptic cleavage sites, those that produced intense MS signals, and those that resulted from proteins generating many distinct peptides. Reproducibility among different instruments of the same type lagged behind

Peptides corresponding to the predicted heptad repeat 2 domain of the feline coronavirus spike protein are potent inhibitors of viral infection.

Directory of Open Access Journals (Sweden)

I-Jung Liu

Full Text Available BACKGROUND: Feline infectious peritonitis (FIP is a lethal immune-mediated disease caused by feline coronavirus (FCoV. Currently, no therapy with proven efficacy is available. In searching for agents that may prove clinically effective against FCoV infection, five analogous overlapping peptides were designed and synthesized based on the putative heptad repeat 2 (HR2 sequence of the spike protein of FCoV, and the antiviral efficacy was evaluated. METHODS: Plaque reduction assay and MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide cytotoxicity assay were performed in this study. Peptides were selected using a plaque reduction assay to inhibit Feline coronavirus infection. RESULTS: The results demonstrated that peptide (FP5 at concentrations below 20 μM inhibited viral replication by up to 97%. The peptide (FP5 exhibiting the most effective antiviral effect was further combined with a known anti-viral agent, human interferon-α (IFN-α, and a significant synergistic antiviral effect was observed. CONCLUSION: Our data suggest that the synthetic peptide FP5 could serve as a valuable addition to the current FIP prevention methods.

TETRA Backhauling via Satellite: Improving Call Setup Times and Saving Bandwidth

Directory of Open Access Journals (Sweden)

Anton Donner

2014-01-01

Full Text Available In disaster management scenarios with seriously damaged, not existing, or saturated communication infrastructures satellite communications can be an ideal means to provide connectivity with unaffected remote terrestrial trunked radio (TETRA core networks. However, the propagation delay imposed by the satellite link affects the signalling protocols. This paper discusses the suitability of using a satellite link for TETRA backhauling, introducing two different architectures. In order to cope with the signal delay of the satellite link, the paper proposes and analyzes a suitable solution based on the use of a performance enhancing proxy (PEP. Additionally, robust header compression (ROHC is discussed as suitable technology to transmit TETRA voice via IP-based satellite networks.

Sungsanpin, a lasso peptide from a deep-sea streptomycete.

Science.gov (United States)

Um, Soohyun; Kim, Young-Joo; Kwon, Hyuknam; Wen, He; Kim, Seong-Hwan; Kwon, Hak Cheol; Park, Sunghyouk; Shin, Jongheon; Oh, Dong-Chan

2013-05-24

Sungsanpin (1), a new 15-amino-acid peptide, was discovered from a Streptomyces species isolated from deep-sea sediment collected off Jeju Island, Korea. The planar structure of 1 was determined by 1D and 2D NMR spectroscopy, mass spectrometry, and UV spectroscopy. The absolute configurations of the stereocenters in this compound were assigned by derivatizations of the hydrolysate of 1 with Marfey's reagents and 2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl isothiocyanate, followed by LC-MS analysis. Careful analysis of the ROESY NMR spectrum and three-dimensional structure calculations revealed that sungsanpin possesses the features of a lasso peptide: eight amino acids (-Gly(1)-Phe-Gly-Ser-Lys-Pro-Ile-Asp(8)-) that form a cyclic peptide and seven amino acids (-Ser(9)-Phe-Gly-Leu-Ser-Trp-Leu(15)) that form a tail that loops through the ring. Sungsanpin is thus the first example of a lasso peptide isolated from a marine-derived microorganism. Sungsanpin displayed inhibitory activity in a cell invasion assay with the human lung cancer cell line A549.

STUDY OF SUBCELLULAR DISTRIBUTION OF CRYSTALLINE MESO-TETRA(3-PYRIDYLBACTERIOCHLORIN NANOPARTICLES

Directory of Open Access Journals (Sweden)

Yu. S. Maklygina

2016-01-01

Full Text Available The results of the study of subcellular distribution of molecular meso-tetra(3-pyridylbacteriochlorin nanocrystals proposed as therapeutic agents for photodynamic therapy are represented in the article. Investigations and measurement of spectroscopic properties of molecular crystals of near-infrared photosensitizer were conducted using special device complex based on fiber-optic spectrometer. Investigation and analysis of the pattern of subcellular accumulation of meso-tetra(3-pyridylbacteriochlorin in molecular (dimethyl sulfoxide (DMSO as solvent and nanocrystalline forms on different cell lines: human monocytes (THP-1, human cervical cancer cells (HeLa and mouse malignant brain tumor cells (glioma C6. The dynamics of subcellylar accumulation of the agent at concentration of 5 and 10 mg/l was assessed with laser microscope-spectrum analyzer and by confocal microscopy. The study showed that in the course of interaction with cell lines molecular nanocrystals of the agent developed ability to fluorescence. Hence, in the cellular environment meso-tetra(3-pyridyl bacteriochlorin nanoparticles became phototoxic giving opportunities for their use for fluorescence diagnosis and photodynamic therapy. Specific role of meso-tetra(3-pyridylbacteriochlorin in the range of photosensitizers is determined by its spectral characteristics, i.e. absorption and fluorescence in near-infrared band, which allows measuring and affecting on deeper layers of biotissue. Thus, the use of meso-tetra(3-pyridylbacteriochlorin nanoparticles as nanophotosensitizers may improve the efficacy of diagnosis and treatment of deep-seated tumors.

The TETRA-II Experiment to Observe Terrestrial Gamma Flashes at Ground Level - Preliminary Results

Science.gov (United States)

Cherry, M. L.; Adams, C.; Al-Nussirat, S.; Bai, S.; Banadaki, Y.; Bitzer, P. M.; Hoffmann, J.; Khosravi, E.; Legault, M.; Orang, M.; Pleshinger, D. J.; Rodriguez, R.; Smith, D.; Trepanier, J. C.; Sunda-Meya, A.; Zimmer, N.

2017-12-01

An upgraded version of the TGF and Energetic Thunderstorm Rooftop Array (TETRA-II) consists of an array of BGO scintillators to detect bursts of gamma rays from thunderstorms at ground level in four separate locations: the campus of Louisiana State University in Baton Rouge, Louisiana; the campus of the University of Puerto Rico at Utuado, Puerto Rico; the Centro Nacional de Metrologia de Panama (CENAMEP) in Panama City, Panama; and the Severe Weather Institute and Radar & Lightning Laboratories in Huntsville, Alabama. The original TETRA-I array of NaI scintillators at Louisiana State University detected 37 millisecond-scale bursts of gamma rays at energies 50 keV-2 MeV associated with nearby (brief description of the TETRA-I observations, a description of TETRA-II, and preliminary results of the first events observed by TETRA-II will be presented including frequency and time history of events, spectral information, and correlation with local radar and radio data.

Di-?-cyanido-tetra?cyanido(5,5,7,12,12,14-hexa?methyl-1,4,8,11-tetra?aza?cyclo?tetra?decane)[N-(quinolin-8-yl)quinoline-2-carboxamidato]diiron(III)nickel(II) 2.07-hydrate

OpenAIRE

Yang, Yuqi; Zhou, Hongbo; Shen, Xiaoping

2013-01-01

The asymmetric unit of the title complex, [Fe2Ni(C19H12N3O)2(CN)6(C16H36N4)]?2.07H2O, contains one [Fe(qcq)(CN)3]? anion, half a [Ni(teta)]2+ cation and two partially occupied inter?stitial water mol?ecules [qcq? is the N-(quinolin-8-yl)quinoline-2-carboxamidate anion and teta is 5,5,7,12,12,14-hexa?methyl-1,4,8,11-tetra?aza?cyclo?tetra?deca?ne]. In the complex mol?ecule, two [Fe(qcq)(CN)3]? anions additionally coordinate the central [Ni(teta)]2+ cation through cyanide groups in a trans mode,...

Improvement of an enzyme-linked immunosorbent assay for equine herpesvirus type 4 by using a synthetic-peptide 24-mer repeat sequence of glycoprotein G as an antigen.

Science.gov (United States)

Bannai, Hiroshi; Nemoto, Manabu; Tsujimura, Koji; Yamanaka, Takashi; Maeda, Ken; Kondo, Takashi

2016-02-01

To increase the sensitivity of an enzyme-linked immunosorbent assay (ELISA) for equine herpesvirus type 4 (EHV-4) that uses a 12-mer peptide of glycoprotein G (gG4-12-mer: MKNNPIYSEGSL) [4], we used a longer peptide consisting of a 24-mer repeat sequence (gG4-24-mer: MKNNPIYSEGSLMLNVQHDDSIHT) as an antigen. Sera of horses experimentally infected with EHV-4 reacted much more strongly to the gG4-24-mer peptide than to the gG4-12-mer peptide. We used peptide ELISAs to test paired sera from horses naturally infected with EHV-4 (n=40). gG4-24-mer ELISA detected 37 positive samples (92.5%), whereas gG4-12-mer ELISA detected only 28 (70.0%). gG4-24-mer ELISA was much more sensitive than gG4-12-mer ELISA.

Ten tandem repeats of β-hCG 109-118 enhance immunogenicity and anti-tumor effects of β-hCG C-terminal peptide carried by mycobacterial heat-shock protein HSP65

International Nuclear Information System (INIS)

Zhang Yankai; Yan Rong; He Yi; Liu Wentao; Cao Rongyue; Yan Ming; Li Taiming; Liu Jingjing; Wu Jie

2006-01-01

The β-subunit of human chorionic gonadotropin (β-hCG) is secreted by many kinds of tumors and it has been used as an ideal target antigen to develop vaccines against tumors. In view of the low immunogenicity of this self-peptide,we designed a method based on isocaudamer technique to repeat tandemly the 10-residue sequence X of β-hCG (109-118), then 10 tandemly repeated copies of the 10-residue sequence combined with β-hCG C-terminal 37 peptides were fused to mycobacterial heat-shock protein 65 to construct a fusion protein HSP65-X10-βhCGCTP37 as an immunogen. In this study, we examined the effect of the tandem repeats of this 10-residue sequence in eliciting an immune by comparing the immunogenicity and anti-tumor effects of the two immunogens, HSP65-X10-βhCGCTP37 and HSP65-βhCGCTP37 (without the 10 tandem repeats). Immunization of mice with the fusion protein HSP65-X10-βhCGCTP37 elicited much higher levels of specific anti-β-hCG antibodies and more effectively inhibited the growth of Lewis lung carcinoma (LLC) in vivo than with HSP65-βhCGCTP37, which should suggest that HSP65-X10-βhCGCTP37 may be an effective protein vaccine for the treatment of β-hCG-dependent tumors and multiple tandem repeats of a certain epitope are an efficient method to overcome the low immunogenicity of self-peptide antigens

DESIGNAND EVALUATION OF TETRA-PAK CONTAINERS' RECYCLING PLANT ON A SMALLSCALE

OpenAIRE

Inche Mitma, Jorge; Vergiú Canto, Jorge|; Mavila Hinojoza, Daniel; Godoy Martínez, Manuel; Chung Pinzás, Alfonso

2014-01-01

This study deals about the design and evaluation of Tetra Pak containers' recycling plant on a small scale. The basic Plant Engineering was found from the information gathered. Some aspects included were: product design, process design, equipment design and costs evaluation, with the aim of determining its technical, economical and environmental capability for its implementation. El estudio trata sobre el diseño y evaluación de una planta de reciclaje de envases tetra pak a pequeña escala....

Improvement of an enzyme-linked immunosorbent assay for equine herpesvirus type 4 by using a synthetic-peptide 24-mer repeat sequence of glycoprotein G as an antigen

Science.gov (United States)

BANNAI, Hiroshi; NEMOTO, Manabu; TSUJIMURA, Koji; YAMANAKA, Takashi; MAEDA, Ken; KONDO, Takashi

2015-01-01

To increase the sensitivity of an enzyme-linked immunosorbent assay (ELISA) for equine herpesvirus type 4 (EHV-4) that uses a 12-mer peptide of glycoprotein G (gG4-12-mer: MKNNPIYSEGSL) [4], we used a longer peptide consisting of a 24-mer repeat sequence (gG4-24-mer: MKNNPIYSEGSLMLNVQHDDSIHT) as an antigen. Sera of horses experimentally infected with EHV-4 reacted much more strongly to the gG4-24-mer peptide than to the gG4-12-mer peptide. We used peptide ELISAs to test paired sera from horses naturally infected with EHV-4 (n=40). gG4-24-mer ELISA detected 37 positive samples (92.5%), whereas gG4-12-mer ELISA detected only 28 (70.0%). gG4-24-mer ELISA was much more sensitive than gG4-12-mer ELISA. PMID:26424485

Tetra-n-butylammonium borohydride semiclathrate: a hybrid material for hydrogen storage.

Science.gov (United States)

Shin, Kyuchul; Kim, Yongkwan; Strobel, Timothy A; Prasad, P S R; Sugahara, Takeshi; Lee, Huen; Sloan, E Dendy; Sum, Amadeu K; Koh, Carolyn A

2009-06-11

In this study, we demonstrate that tetra-n-butylammonium borohydride [(n-C(4)H(9))(4)NBH(4)] can be used to form a hybrid hydrogen storage material. Powder X-ray diffraction measurements verify the formation of tetra-n-butylammonium borohydride semiclathrate, while Raman spectroscopic and direct gas release measurements confirm the storage of molecular hydrogen within the vacant cavities. Subsequent to clathrate decomposition and the release of physically bound H(2), additional hydrogen was produced from the hybrid system via a hydrolysis reaction between the water host molecules and the incorporated BH(4)(-) anions. The additional hydrogen produced from the hydrolysis reaction resulted in a 170% increase in the gravimetric hydrogen storage capacity, or 27% greater storage than fully occupied THF + H(2) hydrate. The decomposition temperature of tetra-n-butylammonium borohydride semiclathrate was measured at 5.7 degrees C, which is higher than that for pure THF hydrate (4.4 degrees C). The present results reveal that the BH(4)(-) anion is capable of stabilizing tetraalkylammonium hydrates.

The Comparison of Propagation Model for Terrestrial Trunked Radio (TETRA

Directory of Open Access Journals (Sweden)

Ayu Kartika R

2013-12-01

Full Text Available A system of digital radio Terrestrial Trunked Radio (TETRA is designed for communication which need specialility, better privacy, better quality of audio with speed transmission data and access capacity to the internet and telephone network. TETRA system of TMO and DMO operation mode which has wide coverage and reliable than the interference so that the TETRA planning needs a propagation model which corresponding with environment. Therefore, this research compare a pathloss value of calculation of propagation model such as Free Space Loss, Wickson, Bacon, CEPT SE21, Ericsson (9999, ITU-R SM 2028 and Okumura Hata based on the environment are clutter urban, sub urban dan rural. The calculation of pathloss provide that Bacon propagation model is an corresponding model for DMO operation mode with a frequency of 380 MHz, height handhelds 1.5 m and 2 m with pathloss value of 76.82 dB at a distance of 100 m and 113.63 dB at a distance of 1 km while the 400 MHz frequency pathloss value of 77.08 dB at a distance of 100 m and 113.6 dB at a distance of 1 km. The propagation model which corresponding to the TMO operation mode with a frequency of 400 MHz distance of 1 km, the transmitter antenna height (hb 30 m and receiver antenna height (hm 1.5 m is a model of Ericsson (9999 on urban clutter with pathloss value of 96.4 dB, the model ITU-R SM2028 in suburban clutter with a pathloss value of 101.13 dB, and the model ITU-R SM2028 on rural clutter with pathloss value of 83.59 dB. Keywords: TETRA, propagation model, urban, suburban, rural

Facilitation of peptide fibre formation by arginine-phosphate ...

Indian Academy of Sciences (India)

WINTEC

Peptide; self-assembly; arginine; microscopy. ... The latter property, in particular, observed in .... this process repeated till the gummy compound be- ..... micrograph of Congo red-stained image of individual peptide fibre from aged solution of 4.

Tumour uptake of the radiolabelled somatostatin analogue [DOTA0,TYR3]octreotide is dependent on the peptide amount

International Nuclear Information System (INIS)

Jong, M. de; Breeman, W.A.P.; Bernard, B.F.; Gameren, A. van; Bruin, E. de; Bakker, W.H.; Van der Pluijm, M.E.; Krenning, E.P.; Visser, T.J.; Maecke, H.R.

1999-01-01

Radiolabelled tumour receptor-binding peptides can be used for in vivo scintigraphic imaging. Recently, the somatostatin analogue [Tyr 3 ]octreotide (d-Phe-c(Cys-Tyr-d-Trp-Lys-Thr-Cys)-Thr(ol)) was derivatized with the chelator DOTA (tetra-azacyclododecane-tetra-acetic acid), enabling stable radiolabelling with both the high-energy beta particle-emitter yttrium-90 and the Auger electron-emitter indium-111. The thus produced radiolabelled compounds are promising for peptide receptor radionuclide therapy. Our previous in vitro and in vivo (rat) experiments with these radiolabelled compounds showed favourable binding and biodistribution characteristics with high uptake and retention in the target organs. We also demonstrated receptor-specific, time- and temperature-dependent internalization of radiolabelled [DOTA 0 ,Tyr 3 ]octreotide in somatostatin receptor subtype 2 (sst 2 )-positive rat pancreatic tumour cell lines. In this study we have investigated the effects of differences in the amount of injected peptide on tissue distribution of 111 In-labelled [DOTA 0 ,Tyr 3 ]octreotide in normal, i.e. non-tumour-bearing, and CA20948 tumour-bearing rats. This was done in order to find the amount of peptide at which the highest uptake in target tissues is achieved, and thereby to increase the potential of radionuclide therapy while simultaneously ensuring the lowest possible radiotoxicity in normal organs. Uptake of radiolabelled [DOTA 0 ,Tyr 3 ]octreotide in sst 2 -positive organs showed different bell-shaped functions of the amount of injected peptide, being highest at 0.05 (adrenals), 0.05-0.1 (pituitary and stomach) and 0.25 (pancreas) μg. Uptake in the tumour was highest at 0.5 μg injected peptide. The highest uptake was found at peptide amounts that were lower than those reported for [ 111 In-DTPA 0 ]octreotide (d-Phe-c(Cys-Phe-d-Trp-Lys-Thr-Cys)-Thr(ol), DTPA = diethylene-triamine-penta-acetic acid), consistent with the higher receptor affinity of the first compound

La prosodia como identificador biométrico

OpenAIRE

Farrús i Cabeceran, Mireia

2011-01-01

La biometría tiene como objetivo el reconocimiento de personas mediante uno o más identificadores biométricos como la voz, la cara o las huellas dactilares, entre otros. Gracias a la buena aceptación social y el poco intrusismo en los individuos, la voz ha sido, tradicionalmente, uno de los identificadores más utilizados en los sistemas biométricos. Estos sistemas de reconocimiento basados en la voz utilizan, habitualmente, características relacionadas con el espectro de la voz. No obstante, ...

Tetra-ataxiometric Posturography in Patients with Migrainous Vertigo.

Science.gov (United States)

Ongun, Nedim; Atalay, Nilgun S; Degirmenci, Eylem; Sahin, Fusun; Bir, Levent Sinan

2016-01-01

Migraine is a common disorder characterized by headache attacks frequently accompanied by vestibular symptoms like dizziness, vertigo, and balance disorders. Clinical studies support a strong link between migraine and vertigo rather than between other headache types and vertigo or nonvertiginous dizziness. There is a lack of consensus regarding the pathophysiology of migrainous vertigo. Activation of central vestibular processing during migraine attacks and vasospasm-induced ischemia of the labyrinth are reported as the probable responsible mechanisms. Because vestibular examination alone does not provide enough information for diagnosis of migrainous vertigo, posturography systems which provide objective assessment of somatosensory, vestibular, and visual information would be very helpful to show concomitant involvement of the vestibular and somato-sensorial systems. There are few posturographic studies on patients with migraine but it seems that how balance is affected in patients with migraine and/or migrainous vertigo is still not clear. We want to investigate balance function in migraineurs with and without vertigo with a tetra-ataxiometric posturography system and our study is the first study in which tetra-ataxiometric static posturography was used to evaluate postural abnormalities in a well-defined population of patients with migrainous vertigo. To investigate balance functions in migraineurs with and without vertigo with a tetra-ataxiometric posturography system. Prospective, nonrandomized, controlled study. Pamukkale University Hospital, Neurology and Physical Therapy and Rehabilitation outpatient clinics. Sixteen patients with migrainous vertigo, 16 patients with migraine without aura and no vestibular symptoms, and 16 controls were included in the study. Computerized static posturography system was performed and statistical analyses of fall, Fourier, Stability, and Weight distribution indexes were performed. The tetra-ataxiometric posturography device

Assembling of G-strands into novel tetra-molecular parallel G4-DNA nanostructures using avidin-biotin recognition.

Science.gov (United States)

Borovok, Natalia; Iram, Natalie; Zikich, Dragoslav; Ghabboun, Jamal; Livshits, Gideon I; Porath, Danny; Kotlyar, Alexander B

2008-09-01

We describe a method for the preparation of novel long (hundreds of nanometers), uniform, inter-molecular G4-DNA molecules composed of four parallel G-strands. The only long continuous G4-DNA reported so far are intra-molecular structures made of a single G-strand. To enable a tetra-molecular assembly of the G-strands we developed a novel approach based on avidin-biotin biological recognition. The steps of the G4-DNA production include: (i) Enzymatic synthesis of long poly(dG)-poly(dC) molecules with biotinylated poly(dG)-strand; (ii) Formation of a complex between avidin-tetramer and four biotinylated poly(dG)-poly(dC) molecules; (iii) Separation of the poly(dC) strands from the poly(dG)-strands, which are connected to the avidin; (iv) Assembly of the four G-strands attached to the avidin into tetra-molecular G4-DNA. The average contour length of the formed structures, as measured by AFM, is equal to that of the initial poly(dG)-poly(dC) molecules, suggesting a tetra-molecular mechanism of the G-strands assembly. The height of tetra-molecular G4-nanostructures is larger than that of mono-molecular G4-DNA molecules having similar contour length. The CD spectra of the tetra- and mono-molecular G4-DNA are markedly different, suggesting different structural organization of these two types of molecules. The tetra-molecular G4-DNA nanostructures showed clear electrical polarizability. This suggests that they may be useful for molecular electronics.

Simulations for the neutron detector TETRA with MCNP

International Nuclear Information System (INIS)

Testov, D.; Kuznetsova, E.; Wilson, Jh.

2013-01-01

To study the nuclear structure of β-delayed neutron precursors at ALTO ISOL-facility at IPN (Orsay), the high efficiency 4π neutron detector TETRA with 3 He filled counters built at JINR (Dubna) was modified. The MCNP simulations to optimize the future configuration were necessary. The details of the calculations and the major results obtained are discussed

Tetra-phocomelia: the seal limb deformity - a case report.

Science.gov (United States)

Samal, Sunil Kumar; Rathod, Setu; Ghose, Seetesh

2015-02-01

We report a case of term live baby with tetra-phocomelia born to a 35-year-old G3P2L2A0 with history of consanguineous marriage. She was an unbooked case from a tribal community with no previous antenatal visits. At 39 wk of gestation, she was admitted to our hospital with complaint of pain abdomen and on examination was found to be in second stage of labour. She delivered vaginally a term live 2.5 kg female baby with multiple anomalies. There was no history of drug intake, radiation exposure, maternal diabetes or family history of congenital anomalies to support the occurrence of tetra-phocomelia in this baby. The neonate also had multiple facial abnormalities like hypertelorism, microretrognathia and partial cleft palate. Further investigations revealed no abnormalities of internal organs. At present the baby is being followed up at our paediatric department. The case is reported owing to its rarity and term live birth.

Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

International Nuclear Information System (INIS)

Long, Yan; Lin, Zuoxian; Xia, Menghang; Zheng, Wei; Li, Zhiyuan

2013-01-01

Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependent inhibitions of HERG channel currents with IC 50 values of 4 nM and 17 nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I–V curves in a hyperpolarized direction for 10–15 mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I–V curve in a hyperpolarized direction for 24.4 mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners. - Highlights: ► Tetra-n-octylammonium and benzethonium are potent HERG channel inhibitors. ► Channel activation and inactivation processes are accelerated by the two compounds. ► Both compounds are the open-channel blockers to HERG channels. ► HERG channel inhibition by both compounds is use-, voltage- and state dependent. ► The in vivo risk of QT prolongation needs to be studied for the two compounds

Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

Energy Technology Data Exchange (ETDEWEB)

Long, Yan; Lin, Zuoxian [Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530 (China); Xia, Menghang; Zheng, Wei [National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Zhiyuan, E-mail: li_zhiyuan@gibh.ac.cn [Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530 (China)

2013-03-01

Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependent inhibitions of HERG channel currents with IC{sub 50} values of 4 nM and 17 nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I–V curves in a hyperpolarized direction for 10–15 mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I–V curve in a hyperpolarized direction for 24.4 mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners. - Highlights: ► Tetra-n-octylammonium and benzethonium are potent HERG channel inhibitors. ► Channel activation and inactivation processes are accelerated by the two compounds. ► Both compounds are the open-channel blockers to HERG channels. ► HERG channel inhibition by both compounds is use-, voltage- and state dependent. ► The in vivo risk of QT prolongation needs to be studied for the two compounds.

RNA FISH for detecting expanded repeats in human diseases.

Science.gov (United States)

Urbanek, Martyna O; Krzyzosiak, Wlodzimierz J

2016-04-01

RNA fluorescence in situ hybridization (FISH) is a widely used technique for detecting transcripts in fixed cells and tissues. Many variants of RNA FISH have been proposed to increase signal strength, resolution and target specificity. The current variants of this technique facilitate the detection of the subcellular localization of transcripts at a single molecule level. Among the applications of RNA FISH are studies on nuclear RNA foci in diseases resulting from the expansion of tri-, tetra-, penta- and hexanucleotide repeats present in different single genes. The partial or complete retention of mutant transcripts forming RNA aggregates within the nucleoplasm has been shown in multiple cellular disease models and in the tissues of patients affected with these atypical mutations. Relevant diseases include, among others, myotonic dystrophy type 1 (DM1) with CUG repeats, Huntington's disease (HD) and spinocerebellar ataxia type 3 (SCA3) with CAG repeats, fragile X-associated tremor/ataxia syndrome (FXTAS) with CGG repeats, myotonic dystrophy type 2 (DM2) with CCUG repeats, amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) with GGGGCC repeats and spinocerebellar ataxia type 32 (SCA32) with GGCCUG. In this article, we summarize the results obtained with FISH to examine RNA nuclear inclusions. We provide a detailed protocol for detecting RNAs containing expanded CAG and CUG repeats in different cellular models, including fibroblasts, lymphoblasts, induced pluripotent stem cells and murine and human neuronal progenitors. We also present the results of the first single-molecule FISH application in a cellular model of polyglutamine disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Computationally assisted screening and design of cell-interactive peptides by a cell-based assay using peptide arrays and a fuzzy neural network algorithm.

Science.gov (United States)

Kaga, Chiaki; Okochi, Mina; Tomita, Yasuyuki; Kato, Ryuji; Honda, Hiroyuki

2008-03-01

We developed a method of effective peptide screening that combines experiments and computational analysis. The method is based on the concept that screening efficiency can be enhanced from even limited data by use of a model derived from computational analysis that serves as a guide to screening and combining the model with subsequent repeated experiments. Here we focus on cell-adhesion peptides as a model application of this peptide-screening strategy. Cell-adhesion peptides were screened by use of a cell-based assay of a peptide array. Starting with the screening data obtained from a limited, random 5-mer library (643 sequences), a rule regarding structural characteristics of cell-adhesion peptides was extracted by fuzzy neural network (FNN) analysis. According to this rule, peptides with unfavored residues in certain positions that led to inefficient binding were eliminated from the random sequences. In the restricted, second random library (273 sequences), the yield of cell-adhesion peptides having an adhesion rate more than 1.5-fold to that of the basal array support was significantly high (31%) compared with the unrestricted random library (20%). In the restricted third library (50 sequences), the yield of cell-adhesion peptides increased to 84%. We conclude that a repeated cycle of experiments screening limited numbers of peptides can be assisted by the rule-extracting feature of FNN.

Kinetic stabilities of double, tetra- and hexarosette hydrogen-bonded assemblies

NARCIS (Netherlands)

Prins, L.J.; Neuteboom, Edda E.; Paraschiv, V.; Crego Calama, Mercedes; Timmerman, P.; Reinhoudt, David

2002-01-01

A study of the kinetic stabilities of hydrogen-bonded double, tetra-, and hexarosette assemblies, comprising 36, 72, and 108 hydrogen bonds, respectively, is described. The kinetic stabilities are measured using both chiral amplification and racemization experiments. The chiral amplification studies

''Cs-tetra-ferri-annite:'' High-pressure and high-temperature behavior of a potential nuclear waste disposal phase

International Nuclear Information System (INIS)

Comodi, P.; Zanazzi, P.F.

1999-01-01

Structure deformations induced by pressure and temperature in synthetic Cs-tetra-ferri-annite 1M [Cs 1.78 (Fe 2+ 5.93 Fe 3+ 0.07 )(Si 6.15 Fe 3+ 1.80 Al 0.05 )O 20 (OH) 4 ], space group C2/m, were analyzed to investigate the capability of the mica structure to store the radiogenic isotopes 135 Cs and 137 Cs. Cs-tetra-ferri-annite is not a mineral name, but for the sake of brevity is used here to designate a synthetic analog of the mineral tetra-ferri-annite. The bulk modulus and its pressure derivative determined by fitting the unit-cell volumes between 0 a/nd 47 kbar to a third-order Birch-Murnaghan equation of state are K 0 = 257(8) kbar and K' 0 = 21(1), respectively. Between 23 C and 582 C, the a and b lattice parameters remain essentially unchanged, but the thermal expansion coefficient of the c axis is α c = 3.12(9) x 10 -5 degree C -1 . High pressure (P) and high temperature (T) produce limited internal strain in the structure. The tetrahedral rotation angle, α, is very small and does not change significantly throughout the P and T range investigated. Above 450 C in air, Cs-tetra-ferri-annite underwent an oxidation of octahedral iron in the M2cis site, balanced by the loss of H and shown by a decrease of the unit-cell volume. Independent isobaric data on thermal expansion and isothermal compressibility data define the geometric equation of state for Cs-tetra-ferri-annite. On the whole, the data confirm that the structure of Cs-tetra-ferri-annite may be a suitable candidate for the storage of large ions, such as Cs in the interlayer and should be considered as a potential Synroc component

Dibromidobis(N,N,N′,N′-tetra­methyl­thio­urea-κS)cadmium(II)

Science.gov (United States)

Nawaz, Sidra; Sadaf, Sana; Fettouhi, Mohammed; Fazal, Atif; Ahmad, Saeed

2010-01-01

In the title compound, [CdBr2(C5H12N2S)2], the CdII atom lies on a twofold rotation axis. It exhibits a distorted tetra­hedral coordination environment defined by two S atoms of two tetra­methyl­thio­urea (tmtu) ligands and two bromide ions. The crystal structure is consolidated by C—H⋯N and C—H⋯S hydrogen bonds. PMID:21588180

El desarrollo geométrico de la representación espacial

OpenAIRE

Mongeau, Piere; Pallascio, Richard; Allaire, Richar

1990-01-01

Los autores emitieron la hipótesis de que la evaluación del desarrollo geométrico de la representación espacial se repite, desde la infancia hasta la edad adulta, sobre la relación jerárquica de los niveles geométricos (topológico, proyectivo, afín y métrico). Como no se ha encontrado ningún instrumento de investigación geométricamente completo y válido, los autores han construido uno. Grupos de individuos de diferentes edades, —jóvenes (ll-12 años), adolescentes (15-16 años), adultos jóvenes...

Microwave absorption behaviors of tetra-needle-like ZnO whiskers

International Nuclear Information System (INIS)

Zhou Zuowan; Chu Longsheng; Hu Shuchun

2006-01-01

A novel type of microwave absorption coating was prepared using tetra-needle-like zinc oxide whiskers as the main functional agent. The results of the experiments show that the composite coatings containing ZnO whisker appear to have good efficiency of microwave absorption, and the effect is influenced by the aspect ratio (length to diameter, L/D), the content of the T-ZnO whiskers and the resistivity of the whiskers. Microwave-heat transformation of this kind of whisker and its composite was investigated, and the results indicated that the apparent density affected the efficiency of the heat generating. The suitable value of the apparent density is 0.16-0.18 g/cm 3 . The mechanism of microwave absorption and microwave-heat transformation was explained by the semiconductive networks formed by the tetra-needle shape, diffuse reflections results from quasi-antenna, multipoles due to charge concentration and the multi-interfaces in the composites

SUSTENTABILIDADE INSTITUCIONAL NO SETOR ELÉTRICO BRASILEIRO

Directory of Open Access Journals (Sweden)

Fabricio Quadros Borges

2015-05-01

Full Text Available As instituições do setor elétrico brasileiro enfrentam grandes desafios de mercado que pressionam estas organizações para que sejam capazes de planejar constantemente ações integradas e sustentáveis. Estes desafios estão vinculados ao atendimento premente por eletricidade e a necessidade de operar mecanismos eficientes para lidar com as questões ambientais. Nesta perspectiva, este estudo objetiva apurar o grau de sustentabilidade da dimensão institucional nas instituições de regulação e de supervisão do setor elétrico no Brasil. A metodologia baseou-se nos indicadores de sustentabilidade da dimensão institucional elaborados pelo Instituto Brasileiro de Geografia e Estatística - IBGE e utilizou como fontes os relatórios produzidos pelas instituições pesquisadas nas áreas de gestão, auditoria, controle interno, informações gerais e pareceres técnicos. O estudo verificou que dentre as instituições que regulam e supervisionam o setor elétrico no país apenas a Agência Nacional de Energia Elétrica - Aneel apresentou grau de sustentabilidade institucional alto, isto é, grau 15 em uma escala de 6 a 18 pontos.

Migration of itx (Isopropyl Thioxantone from Tetra Pak Bricks into Food

Directory of Open Access Journals (Sweden)

Sonja Jamnicki

2010-01-01

Full Text Available At the beginning of September 2005, itx, a photoinitiator used in uv cured ink, has been identified to have migrated from packaging to food products. Tetra Pak has identified the source of migration to be uv cured offset printing ink.The presence of itx in food packed in Tetra Pak bricks is the result of the contamination of the inner polyethylene layer of the box walls. itx can either migrate through the packaging material or it can reach the food by contact, for example, as a result of the print set-off phenomenon. Most likely, the transfer of itx was due to the physical contact between the printed outer layer with the inner layer of the packaging, whereby the ink or ink substance transfers from the print to the reverse of the adjacent sheet.Tetra Pak has committed itself to move away from this technology immediately and to use alternative printing technologies to ensure that there is no or minimal migration of itx or other substances from its packages.itx is still not on the eu’s negative list of banned substances in food nor does the World Health Organization (who categorize it as being detrimental to human health. After an investigation in the health risks of itx following the incident, the European Food Safety Authority (efsa concluded that the levels found in foods, “while undesirable, do not give cause for health concern.”

Migration of ITX (Isopropyl Thioxantone from Tetra Pak Bricks into Food

Directory of Open Access Journals (Sweden)

Tatjana Jamnicki

2010-06-01

Full Text Available At the beginning of September 2005, ITX, a photoinitiator used in uv cured ink, has been identified to have migrated from packaging to food products. Tetra Pak has identified the source of migration to be uv cured offset printing ink.The presence of ITX in food packed in Tetra Pak bricks is the result of the contamination of the inner polyethylene layer of the box walls. ITX can either migrate through the packaging material or it can reach the food by contact, for example, as a result of the print set-off phenomenon. Most likely, the transfer of ITX was due to the physical contact between the printed outer layer with the inner layer of the packaging, whereby the ink or ink substance transfers from the print to the reverse of the adjacent sheet.Tetra Pak has committed itself to move away from this technology immediately and to use alternative printing technologies to ensure that there is no or minimal migration of ITX or other substances from its packages.ITX is still not on the eu’s negative list of banned substances in food nor does the World Health Organization (WHO categorize it as being detrimental to human health. After an investigation in the health risks of ITX following the incident, the European Food Safety Authority (EFSA concluded that the levels found in foods, “while undesirable, do not give cause for health concern.”

No Effect of TETRA Hand Portable Transmission Signals on Human Cognitive Function and Symptoms

DEFF Research Database (Denmark)

Riddervold, Ingunn Skogstad; Kjærgaard, Søren K.; Pedersen, Gert F.

2010-01-01

Current radio frequency radiation exposure guidelines rest on well-established thermal effects. However, recent research into analogue and digital transmission fields at levels covered by the exposure guidelines has indicated possible detrimental effects on human cognitive performance. To investi......Current radio frequency radiation exposure guidelines rest on well-established thermal effects. However, recent research into analogue and digital transmission fields at levels covered by the exposure guidelines has indicated possible detrimental effects on human cognitive performance....... To investigate this, we conducted a controlled climate chamber study of possible changes in cognitive performance in healthy volunteers exposed to transmission signals from TETRA hand portables (TETRA handsets). The trial deployed a balanced, randomized, double-blinded cross-over design. Performance on different...... paper-and-pencil, auditory and computer-based cognitive tasks was monitored in 53 male volunteers (mean age 36.41 years, SD 8.35) during 45-min exposure to a TETRA handset and sham control signals remotely controlled from a laboratory more than 100 km away. The main cognitive outcome was the Trail...

Tetra-combined cogeneration system. Exergy and thermoeconomic evaluation; Sistema tetra combinado de cogeracao. Avaliacao exergetica e termoeconomica

Energy Technology Data Exchange (ETDEWEB)

Arriola, Domingo Wilson Garagatti [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: wgarriol@usp.br; Oliveira Junior, Silvio de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)]. E-mail: olivsilj@ipt.br

2000-07-01

The description and the exergy and thermo economic evaluation of a new cogeneration system, called tetra-combined cogeneration system, that generates electricity and chilled water (for air conditioning purposes) and eventually steam is presented. This system is composed of a gas turbine, a heat recovery steam generator, a condensation/extraction steam turbine and a hybrid absorption/steam ejection chiller.The exergy and thermo economic performance (exergy based costs of electricity, steam and chilled water production) of this system is compared with the performances of conventional cogeneration systems, pointing out the advantages and disadvantages of this new system. (author)

Understanding the scale of the single ion free energy: A critical test of the tetra-phenyl arsonium and tetra-phenyl borate assumption

Science.gov (United States)

Duignan, Timothy T.; Baer, Marcel D.; Mundy, Christopher J.

2018-06-01

The tetra-phenyl arsonium and tetra-phenyl borate (TATB) assumption is a commonly used extra-thermodynamic assumption that allows single ion free energies to be split into cationic and anionic contributions. The assumption is that the values for the TATB salt can be divided equally. This is justified by arguing that these large hydrophobic ions will cause a symmetric response in water. Experimental and classical simulation work has raised potential flaws with this assumption, indicating that hydrogen bonding with the phenyl ring may favor the solvation of the TB- anion. Here, we perform ab initio molecular dynamics simulations of these ions in bulk water demonstrating that there are significant structural differences. We quantify our findings by reproducing the experimentally observed vibrational shift for the TB- anion and confirm that this is associated with hydrogen bonding with the phenyl rings. Finally, we demonstrate that this results in a substantial energetic preference of the water to solvate the anion. Our results suggest that the validity of the TATB assumption, which is still widely used today, should be reconsidered experimentally in order to properly reference single ion solvation free energy, enthalpy, and entropy.

In silico analysis of Simple Sequence Repeats from chloroplast genomes of Solanaceae species

Directory of Open Access Journals (Sweden)

Evandro Vagner Tambarussi

2009-01-01

Full Text Available The availability of chloroplast genome (cpDNA sequences of Atropa belladonna, Nicotiana sylvestris, N.tabacum, N. tomentosiformis, Solanum bulbocastanum, S. lycopersicum and S. tuberosum, which are Solanaceae species,allowed us to analyze the organization of cpSSRs in their genic and intergenic regions. In general, the number of cpSSRs incpDNA ranged from 161 in S. tuberosum to 226 in N. tabacum, and the number of intergenic cpSSRs was higher than geniccpSSRs. The mononucleotide repeats were the most frequent in studied species, but we also identified di-, tri-, tetra-, pentaandhexanucleotide repeats. Multiple alignments of all cpSSRs sequences from Solanaceae species made the identification ofnucleotide variability possible and the phylogeny was estimated by maximum parsimony. Our study showed that the plastomedatabase can be exploited for phylogenetic analysis and biotechnological approaches.

Human C-peptide. Pt. 1

International Nuclear Information System (INIS)

Beischer, W.; Keller, L.; Maas, M.; Schiefer, E.; Pfeiffer, E.F.

1976-01-01

Synthetic human C-peptide bearing a tyrosine group at its amino end is labelled with 125 iodine using chloramin T or hydrogen peroxide and lactoperoxidase. The results of the two methods are compared. Antiserum to synthetic human C-peptide (without tyrosine), which was partially coupled to rabbit albumin, is raised in guinea pigs and goats. Goats show to be superior to guinea pips concerning antibody production. The so-called 'hook effect' phenomenon is observed when setting up the standard curves for the radioimmunoassay. Monotonically decreasing standard curves are obtained on dilution of antiserum with a high antibody titer which was produced by repeated immunization in goats. Free C-peptide and C-peptide bound to antiserum are separated using the anion exchange resin amberlite. Using this separation technique we excluded unspecific binding of labelled C-peptide to protein fractions in serum of diabetics. The sensitivity of our radioimmunoassay is approx. 0.3 ng C-peptide/ml serum. Intra- and interassay variability are below 10%. Human proinsulin is the only substance found to crossreact with the antiserum. (orig.) [de

Di-μ-cyanido-tetra-cyanido(5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane)[N-(quinolin-8-yl)quinoline-2-carboxamidato]diiron(III)nickel(II) 2.07-hydrate.

Science.gov (United States)

Yang, Yuqi; Zhou, Hongbo; Shen, Xiaoping

2013-05-01

The asymmetric unit of the title complex, [Fe2Ni(C19H12N3O)2(CN)6(C16H36N4)]·2.07H2O, contains one [Fe(qcq)(CN)3](-) anion, half a [Ni(teta)](2+) cation and two partially occupied inter-stitial water mol-ecules [qcq(-) is the N-(quinolin-8-yl)quinoline-2-carboxamidate anion and teta is 5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-deca-ne]. In the complex mol-ecule, two [Fe(qcq)(CN)3](-) anions additionally coordinate the central [Ni(teta)](2+) cation through cyanide groups in a trans mode, resulting in a trinuclear structure with the Ni(2+) cation lying on an inversion centre. The two inter-stitial water mol-ecules are partially occupied, with occupancy factors of 0.528 (10) and 0.506 (9). O-H⋯O and O-H⋯N hydrogen bonding involving the two lattice water molecules and the carbonyl function and a teta N atom in an adjacent cluster leads to the formation of layers extending parallel to (010).

Espacios métricos fuzzy definidos por t-normas.

OpenAIRE

Sapena Piera, Almanzor

2011-01-01

Se prosigue con el estudio de los espacios métricos fuzzy introducidos por George y Veeramani. Se aportan nuevas propiedades y se tratan cuestiones como la completación, la continuidad uniforme y teoremas de punto fijo. Se introducen nuevos ejemplos (alguno de ellos de especial relevancia) y se dan resultados acerca de la precompacidad en espacios métricos fuzzy. Además, se desarrolla el estudio de las métricas fuzzy no arquimedianas y se aborda la cuestión de la completación de los espaci...

Tetra-combined cogeneration system. Exergy and thermo economic evaluation; Sistema tetra combinado de cogeracao. Avaliacao exergetica e termoeconomica

Energy Technology Data Exchange (ETDEWEB)

Arriola, Domingo Wilson Garagatti [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: wgarriol@usp.br; Oliveira Junior, Silvio de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)]. E-mail: olivsilj@ipt.br

2000-07-01

This paper presents the description and the exergy and thermo economic evaluation of a new cogeneration system, called tetra-combined cogeneration system, that generates electricity and chilled water (for air conditioning purposes) and eventually steam. This system is composed of a gas turbine, a heat recovery steam generator, a condensation/extraction steam turbine and a hybrid absorption/steam ejection chiller. The exergy and thermo economic performance (exergy based costs of electricity, steam and chilled water production) of this system is compared with the performances of conventional cogeneration systems, pointing out the advantages and disadvantages of this new system. (author)

Peculiarities of hardware implementation of generalized cellular tetra automaton

OpenAIRE

Аноприенко, Александр Яковлевич; Федоров, Евгений Евгениевич; Иваница, Сергей Васильевич; Альрабаба, Хамза

2015-01-01

Cellular automata are widely used in many fields of knowledge for the study of variety of complex real processes: computer engineering and computer science, cryptography, mathematics, physics, chemistry, ecology, biology, medicine, epidemiology, geology, architecture, sociology, theory of neural networks. Thus, cellular automata (CA) and tetra automata are gaining relevance taking into account the hardware and software solutions.Also it is marked a trend towards an increase in the number of p...

ANÁLISIS TERMOGRAVIMÉTRICO EN LA CARACTERIZACIÓN

Directory of Open Access Journals (Sweden)

Camilo Guerrero

2012-10-01

Full Text Available Cinco carbones de los departamentos de Cundinamarca, Boyacá y Norte de Santander (Colombia se caracterizaron mediante análisis próximo, último, reológico, petrográfico, calorífico y termogravimétrico. Los parámetros analizados, especialmente aquellos que determinan las propiedades reológicas,muestran que los carbones estudiados y sus mezclas podrían producir un coque de buena calidad. Se observó la relación inversa entre el contenido de materia volátil y la reflectanciamedia aleatoria de la vitrinita, que se atribuye al aumento de la aromaticidad en la estructura molecular del carbón como una consecuencia del incremento en el rango. Los parámetros derivados del análisis termogravimétrico –máxima velocidad de desvolatilización y temperatura de máxima velocidad de desvolatilización– mostraron buenas correlaciones con la reflectancia media aleatoria de la vitrinita, igual que la máxima velocidad de desvolatilización con la fluidez máxima. Lo anterior indica que el análisis termogravimétrico podría ser una herramienta útil para caracterizar de manera rápida carbones usados en procesos de fabricación de coque metalúrgico.

Sweet Tetra-Trophic Interactions: Multiple Evolution of Nectar Secretion, a Defensive Extended Phenotype in Cynipid Gall Wasps.

Science.gov (United States)

Nicholls, James A; Melika, George; Stone, Graham N

2017-01-01

Many herbivores employ reward-based mutualisms with ants to gain protection from natural enemies. We examine the evolutionary dynamics of a tetra-trophic interaction in which gall wasp herbivores induce their host oaks to produce nectar-secreting galls, which attract ants that provide protection from parasitoids. We show that, consistent with other gall defensive traits, nectar secretion has evolved repeatedly across the oak gall wasp tribe and also within a single genus (Disholcaspis) that includes many nectar-inducing species. Once evolved, nectar secretion is never lost in Disholcaspis, consistent with high defensive value of this trait. We also show that evolution of nectar secretion is correlated with a transition from solitary to aggregated oviposition, resulting in clustered nectar-secreting galls, which produce a resource that ants can more easily monopolize. Such clustering is commonly seen in ant guard mutualisms. We suggest that correlated evolution between maternal oviposition and larval nectar induction traits has enhanced the effectiveness of this gall defense strategy.

Human C-peptide. Pt. 1. Radioimmunoassay

Energy Technology Data Exchange (ETDEWEB)

Beischer, W; Keller, L; Maas, M; Schiefer, E; Pfeiffer, E F [Ulm Univ. (Germany, F.R.). Abt. Innere Medizin, Endokrinologie und Stoffwechsel

1976-08-01

Synthetic human C-peptide bearing a tyrosine group at its amino end is labelled with /sup 125/iodine using chloramin T or hydrogen peroxide and lactoperoxidase. The results of the two methods are compared. Antiserum to synthetic human C-peptide (without tyrosine), which was partially coupled to rabbit albumin, is raised in guinea pigs and goats. Goats show to be superior to guinea pips concerning antibody production. The so-called 'hook effect' phenomenon is observed when setting up the standard curves for the radioimmunoassay. Monotonically decreasing standard curves are obtained on dilution of antiserum with a high antibody titer which was produced by repeated immunization in goats. Free C-peptide and C-peptide bound to antiserum are separated using the anion exchange resin amberlite. Using this separation technique we excluded unspecific binding of labelled C-peptide to protein fractions in serum of diabetics. The sensitivity of our radioimmunoassay is approx. 0.3 ng C-peptide/ml serum. Intra- and interassay variability are below 10%. Human proinsulin is the only substance found to crossreact with the antiserum.

Epitopes of MUC1 Tandem Repeats in Cancer as Revealed by Antibody Crystallography: Toward Glycopeptide Signature-Guided Therapy

Directory of Open Access Journals (Sweden)

Dapeng Zhou

2018-05-01

Full Text Available Abnormally O-glycosylated MUC1 tandem repeat glycopeptide epitopes expressed by multiple types of cancer have long been attractive targets for therapy in the race against genetic mutations of tumor cells. Glycopeptide signature-guided therapy might be a more promising avenue than mutation signature-guided therapy. Three O-glycosylated peptide motifs, PDTR, GSTA, and GVTS, exist in a tandem repeat HGVTSAPDTRPAPGSTAPPA, containing five O-glycosylation sites. The exact peptide and sugar residues involved in antibody binding are poorly defined. Co-crystal structures of glycopeptides and respective monoclonal antibodies are very few. Here we review 3 groups of monoclonal antibodies: antibodies which only bind to peptide portion, antibodies which only bind to sugar portion, and antibodies which bind to both peptide and sugar portions. The antigenicity of peptide and sugar portions of glyco-MUC1 tandem repeat were analyzed according to available biochemical and structural data, especially the GSTA and GVTS motifs independent from the most studied PDTR. Tn is focused as a peptide-modifying residue in vaccine design, to induce glycopeptide-binding antibodies with cross reactivity to Tn-related tumor glycans, but not glycans of healthy cells. The unique requirement for the designs of antibody in antibody-drug conjugate, bi-specific antibodies, and chimeric antigen receptors are also discussed.

Assessment of specific energy absorption rate (SAR) in the head from a TETRA handset

International Nuclear Information System (INIS)

Dimbylow, Peter; Khalid, Mohammed; Mann, Simon

2003-01-01

Finite-difference time-domain (FDTD) calculations of the specific energy absorption rate (SAR) from a representative TETRA handset have been performed in an anatomically realistic model of the head. TETRA (Terrestrial Trunked Radio) is a modern digital private mobile radio system designed to meet the requirements of professional users, such as the police and fire brigade. The current frequency allocations in the UK are 380-385 MHz and 390-395 MHz for the public sector network. A comprehensive set of calculations of SAR in the head was performed for positions of the handset in front of the face and at both sides of the head. The representative TETRA handset considered, operating at 1 W in normal use, will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a monopole antenna operating at 3 W in normal use will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a helical antenna operating at 3 W in normal use will show compliance with the ICNIRP occupational exposure restriction but will be over the public exposure restriction by up to ∼50% if kept in the position of maximum SAR for 6 min continuously

40 CFR 721.9530 - Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal. 721.9530 Section 721.9530 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.9530 Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester...

Effects of salinity and ethylenediamine tetra acetic acid (edta) on the ...

African Journals Online (AJOL)

In this study, the effects of the combined treatment of salinity and ethylenediamine tetra acetic acid (EDTA) on the germination of tomato seeds in Petri-dishes were compared to sole salinity. The treatments consisted of seven concentrations of sodium chloride (NaCL): 0 (control), 10, 50, 100, 250, 500 and 1000 mM.

Modelo unibimodal simétrico-asimétrico con aplicación al estudio del RNA VIH-1

Directory of Open Access Journals (Sweden)

Guillermo Martínez-Flórez

2014-01-01

Full Text Available Se definen dos nuevas distribuciones de probabilidad: modelo unibi- modal simétrico con función de riesgo proporcional a la distribución normal y modelo unibimodal asimétrico con función de riesgo proporcional a la dis- tribución normal asimétrica. Estos modelos permiten ajustar datos censura- dos con comportamiento bimodal y altos (o bajos niveles de curtosis com- parado con la curtosis de la distribución normal y altos (o bajos niveles de asimetría. Además, se estiman los parámetros de los modelos por máxima verosimilitud y se determina la matriz de información observada. La flexibili- dad de la nueva distribución se ilustra ajustando un conjunto de datos reales: el número de moléculas de ARN VIH-1 por mililitros de sangre medida en personas con pruebas confirmadas de presencia del VIH.

ESTUDIO CINEANTROPOMÉTRICO DEL JUGADOR DE TENIS ADOLESCENTE

Directory of Open Access Journals (Sweden)

Gema Torres Luque

2006-01-01

Full Text Available El propósito de este estudio fue aproximarse al perfil cineantropométrico de jugadores de tenis de edad adolescente. Para ello se seleccionaron 75 jugadores de tenis (47 varones y 26 mujeres a los cuales se les determinó el perfil antropométrico, composición corporal y somatotipo, mostrando a su vez las diferencias en cuanto al género. Todas las valoraciones se realizaron siguiendo las recomendaciones del Grupo Español de Cineantropometría, los tenistas fueron evaluados a la misma hora del día. Los resultados muestran diferencias significativamente mayores en los tenistas en peso, talla, perímetros bioestiloide y bicondíleo húmero, así como en diámetros en brazo contraído y perímetro del muslo y pierna. A su vez, las tenistas muestran un mayor porcentaje de grasa corporal y un menor porcentaje de masa ósea, no existiendo diferencias significativas respecto al porcentaje de masa muscular. El somatotipo marca una tendencia ecto mesomórfica para el género masculino, y una tendencia meso endomórfica para el género femenino. El estudio cineantropométrico del tenista adolescente permitirá una aproximación de referencia al perfil funcional del tenista y contribuir al máximo rendimiento deportivo.

Immunogenicity and Safety of the New Inactivated Quadrivalent Influenza Vaccine Vaxigrip Tetra: Preliminary Results in Children ≥6 Months and Older Adults

Directory of Open Access Journals (Sweden)

Emanuele Montomoli

2018-03-01

Full Text Available Since the mid-1980s, two lineages of influenza B viruses have been distinguished. These can co-circulate, limiting the protection provided by inactivated trivalent influenza vaccines (TIVs. This has prompted efforts to formulate quadrivalent influenza vaccines (QIVs, to enhance protection against circulating influenza B viruses. This review describes the results obtained from seven phase III clinical trials evaluating the immunogenicity, safety, and lot-to-lot consistency of a new quadrivalent split-virion influenza vaccine (Vaxigrip Tetra® formulated by adding a second B strain to the already licensed TIV. Since Vaxigrip Tetra was developed by means of a manufacturing process strictly related to that used for TIV, the data on the safety profile of TIV are considered supportive of that of Vaxigrip Tetra. The safety and immunogenicity of Vaxigrip Tetra were similar to those of the corresponding licensed TIV. Moreover, the new vaccine elicits a superior immune response towards the additional strain, without affecting immunogenicity towards the other three strains. Vaxigrip Tetra is well tolerated, has aroused no safety concerns, and is recommended for the active immunization of individuals aged ≥6 months. In addition, preliminary data confirm its immunogenicity and safety even in children aged 6–35 months and its immunogenicity in older subjects (aged 66–80 years.

Hydroxyapatite-binding peptides for bone growth and inhibition

Science.gov (United States)

Bertozzi, Carolyn R [Berkeley, CA; Song, Jie [Shrewsbury, MA; Lee, Seung-Wuk [Walnut Creek, CA

2011-09-20

Hydroxyapatite (HA)-binding peptides are selected using combinatorial phage library display. Pseudo-repetitive consensus amino acid sequences possessing periodic hydroxyl side chains in every two or three amino acid sequences are obtained. These sequences resemble the (Gly-Pro-Hyp).sub.x repeat of human type I collagen, a major component of extracellular matrices of natural bone. A consistent presence of basic amino acid residues is also observed. The peptides are synthesized by the solid-phase synthetic method and then used for template-driven HA-mineralization. Microscopy reveal that the peptides template the growth of polycrystalline HA crystals .about.40 nm in size.

Waste Cellulose from Tetra Pak Packages as Reinforcement of Cement Concrete

Directory of Open Access Journals (Sweden)

Gonzalo Martínez-Barrera

2015-01-01

Full Text Available The development of the packaging industry has promoted indiscriminately the use of disposable packing as Tetra Pak, which after a very short useful life turns into garbage, helping to spoil the environment. One of the known processes that can be used for achievement of the compatibility between waste materials and the environment is the gamma radiation, which had proved to be a good tool for modification of physicochemical properties of materials. The aim of this work is to study the effects of waste cellulose from Tetra Pak packing and gamma radiation on the mechanical properties of cement concrete. Concrete specimens were elaborated with waste cellulose at concentrations of 3, 5, and 7 wt% and irradiated at 200, 250, and 300 kGy of gamma dose. The results show highest improvement on the mechanical properties for concrete with 3 wt% of waste cellulose and irradiated at 300 kGy; such improvements were related with the surface morphology of fracture zones of cement concrete observed by SEM microscopy.

Self-Oscillating Soft Switching Envelope Tracking Power Supply for Tetra2 Base Station

DEFF Research Database (Denmark)

Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2007-01-01

This paper presents a high-efficiency, high-bandwidth solution to implementing an envelope tracking power supply for the RF power amplifier (RFPA) in a Tetra2 base station. The solution is based on synchronous rectified buck topology, augmented with high-side switch zero-current switching (ZCS......) implemented with a series inductor and an external clamping power supply. Combined with advanced power stage components (die-size MOSFETs), a high-performance fixed-frequency self-oscillating (sliding mode) control strategy and a 4th-order output filter, this leads to a compact, effective and efficient...... overall solution switching at 1MHz with 88-95% efficiency. In a class-AB RFPA amplifying a 50kHz bandwidth QAM Tetra2 signal at 4.6W average output power, the use of tracking supply voltage reduced power dissipation by 25W....

A novel monoclonal antibody to a defined peptide epitope in MUC16

DEFF Research Database (Denmark)

Marcos-Silva, Lara; Ricardo, Sara; Chen, Kowa

2015-01-01

with the tandem-repeat region, their epitopes appear to be conformational dependent and not definable by a short peptide. Aberrant glycoforms of MUC16 may constitute promising targets for diagnostic and immunotherapeutic intervention, and it is important to develop well-defined immunogens for induction of potent...... immunodominant linear peptide epitopes within the tandem repeat. We developed one monoclonal antibody, 5E11, reactive with a minimum epitope with the sequence FNTTER. This sequence contains potential N- and O-glycosylation sites and, interestingly, glycosylation blocked binding of 5E11. In immunochemistry...

Do TETRA (Airwave) base station signals have a short-term impact on health and well-being? A randomized double-blind provocation study.

Science.gov (United States)

Wallace, Denise; Eltiti, Stacy; Ridgewell, Anna; Garner, Kelly; Russo, Riccardo; Sepulveda, Francisco; Walker, Stuart; Quinlan, Terence; Dudley, Sandra; Maung, Sithu; Deeble, Roger; Fox, Elaine

2010-06-01

"Airwave" is the new communication system currently being rolled out across the United Kingdom for the police and emergency services, based on the Terrestrial Trunked Radio Telecommunications System (TETRA). Some police officers have complained about skin rashes, nausea, headaches, and depression as a consequence of using their Airwave handsets. In addition, a small subgroup in the population self-report being sensitive to electromagnetic fields (EMFs) in general. We conducted a randomized double-blind provocation study to establish whether short-term exposure to a TETRA base station signal has an impact on the health and well-being of individuals with self-reported "electrosensitivity" and of participants who served as controls. Fifty-one individuals with self-reported electrosensitivity and 132 age- and sex-matched controls participated in an open provocation test; 48 sensitive and 132 control participants went on to complete double-blind tests in a fully screened semianechoic chamber. Heart rate, skin conductance, and blood pressure readings provided objective indices of short-term physiological response. Visual analog scales and symptom scales provided subjective indices of well-being. We found no differences on any measure between TETRA and sham (no signal) under double-blind conditions for either controls or electrosensitive participants, and neither group could detect the presence of a TETRA signal at rates greater than chance (50%). When conditions were not double blind, however, the self-reported electrosensitive individuals did report feeling worse and experienced more severe symptoms during TETRA compared with sham. Our findings suggest that the adverse symptoms experienced by electrosensitive individuals are due to the belief of harm from TETRA base stations rather than to the low-level EMF exposure itself.

PET imaging of tumor neovascularization in a transgenic mouse model with a novel 64Cu-DOTA-knottin peptide

DEFF Research Database (Denmark)

Nielsen, Carsten Haagen; Kimura, Richard H; Withofs, Nadia

2010-01-01

for a noninvasive detection and characterization of smaller lung nodules, thus increasing the chances of positive treatment outcome. In this study, we investigate the ability to characterize lung tumors that spontaneously arise in a transgenic mouse model. The tumors are first identified with small animal CT...... peptide are compared with standard 18F-fluorodeoxyglucose (FDG) PET small animal imaging. Lung nodules as small as 3 mm in diameter were successfully identified in the transgenic mice by small animal CT, and both 64Cu-DOTA-knottin 2.5F and FDG were able to differentiate lung nodules from the surrounding...... followed by characterization with the use of small animal PET with a novel 64Cu-1,4,7,10-tetra-azacylododecane-N,N',N'',N'''-tetraacetic acid (DOTA)-knottin peptide that targets integrins upregulated during angiogenesis on the tumor associated neovasculature. The imaging results obtained with the knottin...

Highly conductive Al-doped tetra-needle-like ZnO whiskers prepared by a solid state method

International Nuclear Information System (INIS)

Wan Cuifeng; Tan Hairen; Jin Shengming; Yang Huaming; Tang Motang; He Jing

2008-01-01

Tetra-needle-like zinc oxide whiskers (T-ZnO W ) were doped with Al 3+ by a solid state method. In this study, modification conditions were thoroughly investigated to obtain low resistivity T-ZnO W , without destroying the tetra-needle-like structure. The Al-doped T-ZnO W was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transition infrared (FT-IR) spectra and electrical resistance measurement. The SEM and XRD results indicated that the tetra-needle-like structure of ZnO whiskers could be well maintained after modification and the doped (0 0 2) face was preferred. FT-IR results showed that the decrease of resistivity of Al-doped T-ZnO W resulted from formation of [AlO 4 ] configuration in T-ZnO W bulk. Experiment results showed that the annealing temperature, doping concentration and type of Al sources affected the resistivity of T-ZnO W considerably. The optimum Al-doped concentration was 7.0 at.% and the resistivity of T-ZnO W could be considerably decreased from 10 8 to 10 2 Ω cm

catena-Poly[[bromidocopper(I)]-?-?2,?1-3-(2-allyl-2H-tetra?zol-5-yl)pyridine

OpenAIRE

Wang, Wei

2008-01-01

The title compound, [CuBr(C9H9N5)] n , has been prepared by the solvothermal treatment of CuBr with 3-(2-allyl-2H-tetra?zol-5-yl)pyridine. It is a new homometallic CuI olefin coord?ination polymer in which the CuI atoms are linked by the 3-(2-allyl-2H-tetra?zol-5-yl)pyridine ligands and bonded to one terminal Br atom each. The organic ligand acts as a bidentate ligand connecting two neighboring Cu centers through the N atom of the pyridine ring and the double bond of the allyl group. A three-...

Synthesis and aggregation study of optically active tetra-β- [(S)-2 ...

Indian Academy of Sciences (India)

Administrator

Abstract. The optically active tetra-β-[(S)-2-octanyloxy]-substituted copper and nickel phthalocyanines ... layer was washed by 100 mL water and dried with ... roform as mobile phase to give pure blue solid 4a: 2⋅26 g ... from the reaction mixtures by extraction with chlo- ... bonding with chiral carbon), 2⋅01–0⋅88 (H bonding.

Photoreceptors in electric field : Fotoreceptores em campo elétrico

OpenAIRE

Juliana Guerra Hühne

2015-01-01

Resumo: Estudos anteriores e evidências experimentais sugerem um papel importante dos campos elétricos endógenos no direcionamento da migração celular, no desenvolvimento e na regeneração celular e na cicatrização de feridas. Em culturas de células, campos elétricos de corrente contínua influenciam a divisão celular, a polaridade, a forma e a motilidade das células. As distrofias das células fotoreceptoras são uma das principais causas de cegueira hereditária no mundo ocidental; a aplicação d...

Photodynamic Therapy of the Murine LM3 Tumor Using Meso-Tetra (4-N,N,N-Trimethylanilinium) Porphine.

Science.gov (United States)

Colombo, L L; Juarranz, A; Cañete, M; Villanueva, A; Stockert, J C

2007-12-01

Photodynamic therapy (PDT) of cancer is based on the cytotoxicity induced by a photosensitizer in the presence of oxygen and visible light, resulting in cell death and tumor regression. This work describes the response of the murine LM3 tumor to PDT using meso-tetra (4-N,N,N-trimethylanilinium) porphine (TMAP). BALB/c mice with intradermal LM3 tumors were subjected to intravenous injection of TMAP (4 mg/kg) followed 24 h later by blue-red light irradiation (λmax: 419, 457, 650 nm) for 60 min (total dose: 290 J/cm(2)) on depilated and glycerol-covered skin over the tumor of anesthetized animals. Control (drug alone, light alone) and PDT treatments (drug + light) were performed once and repeated 48 h later. No significant differences were found between untreated tumors and tumors only treated with TMAP or light. PDT-treated tumors showed almost total but transitory tumor regression (from 3 mm to less than 1 mm) in 8/9 animals, whereas no regression was found in 1/9. PDT response was heterogeneous and each tumor showed different regression and growth delay. The survival of PDT-treated animals was significantly higher than that of TMAP and light controls, showing a lower number of lung metastasis but increased tumor-draining lymph node metastasis. Repeated treatment and reduction of tissue light scattering by glycerol could be useful approaches in studies on PDT of cancer.

Electrochemical and SEM studies of tetra-ammine platinum (II) (Pt(NH3)4)(OH)2 solution

International Nuclear Information System (INIS)

Wan Jeffrey Basirun

2002-01-01

Electrochemical studies include cyclic voltammetry with microelectrodes were done on a solution of tetra-ammine platinum (II) (Pt(NH 3 ) 4 )(OH) 2 at pH 13 and showed that the electrochemical reduction of this compound was no different from the tetra-ammine platinum (II) (Pt(NH 3 ) 4 )(HPO 4 ) at pH 10.4. The solution was instable to high temperatures and results have shown that electroplating can be done at a limited temperature range for longer periods of time or at higher temperatures for short periods of time. Scanning electron microscopy was done on some of the constant current electrodeposited samples at high temperatures and result obtained was satisfactory. (Authors)

Treatment plan quality of tri-Co-60 MR-IGRT system in comparison with that of VMAT

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Min; Park, So Yeon; Kim, Jung In [Dept. of Nuclear Engineering, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Hak Jae; Wu, Hong Gyun [Dept. of Nuclear Engineering, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2016-04-15

The ViewRay{sup TM} system combines a 0.35-T MR imaging system and a radiation therapy system using a total of three Co-60 sources. It can perform static intensity-modulated radiation therapy (IMRT) with multi-leaf collimators (MLCs) with leaf widths of 1.05 cm at the plane of isocenter, at source to axis distance (SAD) of 105 cm. Since the tri-Co-60 MR-IGRT system can acquire near-real-time cine sagittal MR images during treatment, automated respiratory gating can be performed based on these cine images, thus, the target margins for lung stereotactic ablative radiotherapy (SABR) could be reduced considerably by comparison with the internal tarvet volume (ITV) approach. we compared lung SABR treatment plans of the tri-Co-60 MR-IGRT system with gross tumor volume (GTV) to those of volumetric modulated arc therapy (VMAT) using TrueBeam STx™ (Varian Medical Systems, Palo Alto, CA) with ITV in this study. The plan quality of the target volume of the VMAT with ITV was better than that of the GTV-based tri-Co-60 MR-IGRT for lung SABR. No significant differences for OARs were observed between the tri-Co-60 MR-IGRT and VMAT. However, the plan quality of the tri-Co-60 MR-IGRT system was clinically acceptable. Despite the relatively poor plan quality of the tri-Co-60 MR-IGRT system, it still has the advantage of real-time monitoring of tumor motion during treatment.

Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity.

Science.gov (United States)

Wallace, Denise; Eltiti, Stacy; Ridgewell, Anna; Garner, Kelly; Russo, Riccardo; Sepulveda, Francisco; Walker, Stuart; Quinlan, Terence; Dudley, Sandra; Maung, Sithu; Deeble, Roger; Fox, Elaine

2012-01-01

Terrestrial Trunked Radio (TETRA) technology ("Airwave") has led to public concern because of its potential interference with electrical activity in the brain. The present study is the first to examine whether acute exposure to a TETRA base station signal has an impact on cognitive functioning and physiological responses. Participants were exposed to a 420 MHz TETRA signal at a power flux density of 10 mW/m(2) as well as sham (no signal) under double-blind conditions. Fifty-one people who reported a perceived sensitivity to electromagnetic fields as well as 132 controls participated in a double-blind provocation study. Forty-eight sensitive and 132 control participants completed all three sessions. Measures of short-term memory, working memory, and attention were administered while physiological responses (blood volume pulse, heart rate, skin conductance) were monitored. After applying exclusion criteria based on task performance for each aforementioned cognitive measure, data were analyzed for 36, 43, and 48 sensitive participants for these respective tasks and, likewise, 107,125, and 129 controls. We observed no differences in cognitive performance between sham and TETRA exposure in either group; physiological response also did not differ between the exposure conditions. These findings are similar to previous double-blind studies with other mobile phone signals (900-2100 MHz), which could not establish any clear evidence that mobile phone signals affect health or cognitive function. Copyright © 2011 Wiley Periodicals, Inc.

Di-μ-cyanido-tetra­cyanido(5,5,7,12,12,14-hexa­methyl-1,4,8,11-tetra­aza­cyclo­tetra­decane)[N-(quinolin-8-yl)quinoline-2-carboxamidato]diiron(III)nickel(II) 2.07-hydrate

Science.gov (United States)

Yang, Yuqi; Zhou, Hongbo; Shen, Xiaoping

2013-01-01

The asymmetric unit of the title complex, [Fe2Ni(C19H12N3O)2(CN)6(C16H36N4)]·2.07H2O, contains one [Fe(qcq)(CN)3]− anion, half a [Ni(teta)]2+ cation and two partially occupied inter­stitial water mol­ecules [qcq− is the N-(quinolin-8-yl)quinoline-2-carboxamidate anion and teta is 5,5,7,12,12,14-hexa­methyl-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne]. In the complex mol­ecule, two [Fe(qcq)(CN)3]− anions additionally coordinate the central [Ni(teta)]2+ cation through cyanide groups in a trans mode, resulting in a trinuclear structure with the Ni2+ cation lying on an inversion centre. The two inter­stitial water mol­ecules are partially occupied, with occupancy factors of 0.528 (10) and 0.506 (9). O—H⋯O and O—H⋯N hydrogen bonding involving the two lattice water molecules and the carbonyl function and a teta N atom in an adjacent cluster leads to the formation of layers extending parallel to (010). PMID:23723777

A Simple Preparation of 2,3,4,6-Tetra-O-acyl-Gluco-, Galacto- and Mannopyranoses and Relevant Theoretical Study

Directory of Open Access Journals (Sweden)

Minghong Liu

2010-01-01

Full Text Available The deacylation of glucose, galactose and mannose pentaacetates, galactose and mannose penta(3-bromobenzoates, as well as the dealkylation of 2,3,4,6-tetra-O-acetyl and 2,3,4,6-tetra-O-(3-bromobenzoyl methyl α-D-glucopyranosides have been studied. In addition, a computational study on the deacylation of β-D-glucose pentaacetate has been carried out with density functional theory (B3LYP/6-31G*. The anomeric effect during deacetylation and dealkylation has been clearly demonstrated in both experimental and computational results.

Crystal structure, conformational analysis, and molecular dynamics of tetra-0-methyl-(+)-catechin

Science.gov (United States)

Frank R. Fronczek; Richard W. Hemingway; G. Wayne McGraw; Jan P. Steynberg; Carin A. Helfer; Wayne L. Mattice

1993-01-01

The structure of tetra-O-methyl-(+)-catechin has been determined in the crystalline state. Two independent molecules, denoted structure A and structure B, exist in the unit cell. Crystals are triclinic, space group P1, a=4.8125(2) Ǻ, b=12.9148(8) Ǻ, c=13.8862(11) Ǻ, α=86.962(6)°, β=89.120(5)°, γ=...

Análise unidimensional de transdutores piezelétricos baseada no teorema de Thévenin

OpenAIRE

Arnold,Francisco J

2009-01-01

Neste trabalho é apresentado um método de análise de transdutores piezelétricos baseado numa simplificação do circuito elétrico equivalente de Mason. Empregou-se uma adaptação do teorema de Thévenin para analisar o comportamento de transdutores piezelétricos usados como transmissores (conversão de energia elétrica em mecânica), levando em conta uma configuração tipicamente empregada em aplicações de alta potência. Os transdutores foram modelados uni-dimensionalmente considerando-se apenas mod...

Dimensionado y Tolerado Geométrico en las Normas Técnicas Colombianas

OpenAIRE

Jorge Gómez; Javier Romero; Wilver Suaza

2002-01-01

En este artículo se hace una introducción al tema del Dimensionado y Tolerado Geométrico mostrando una comparación con el sistema de Tolerado Convencional y se destacan algunas de sus ventajas. Posteriormente describe seis tipos de error de frecuente ocurrencia en las Normas Técnicas Colombianas -NTC- sobre Dimensionado y Tolerado Geométrico. Se menciona el número de veces aproximado que estos tipos de errores se presentan en cada norma. Finalmente se aborda una discusión y se hace alusión ...

Evaluation of consumer satisfaction using the tetra-class model.

Science.gov (United States)

Clerfeuille, Fabrice; Poubanne, Yannick; Vakrilova, Milena; Petrova, Guenka

2008-09-01

A number of studies have shown the importance of consumers' satisfaction toward pharmacy services. The measurement of patient satisfaction through different elements of services provided is challenging within the context of a dynamic economic environment. Patient satisfaction is the result of long-term established habits and expectations to the pharmacy as an institution. Few studies to date have attempted to discern whether these changes have led to increased patient satisfaction and loyalty, particularly within developing nations. The objective of this study was to evaluate the elements of the services provided in Bulgarian pharmacies and their contribution to consumer satisfaction using a tetra-class model. Three main hypotheses were tested in pharmacies to validate the model in the case of complex services. Additionally, the contribution of the different service elements to the clients' satisfaction was studied. The analysis was based on a survey of customers in central and district pharmacies in Sofia, Bulgaria. The data were analyzed through a correspondence analysis which was applied to the results of the 752 distributed questionnaires. It was observed that different dimensions of the pharmacies contribute uniquely to customer satisfaction, with consumer gender contributing greatly toward satisfaction, with type/location of pharmacy, consumer age, and educational degree also playing a part. The duration of time over which the consumers have been clients at a given pharmacy influences the subsequent service categorization. This research demonstrated that the tetra-class model is suitable for application in the pharmaceutical sector. The model results could be beneficial for both researchers and pharmacy managers.

Propriedades discriminativas e reforçadoras do choque elétrico

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Silvio Morato de Carvalho

Full Text Available Ratos treinados na resposta de pressão à barra reforçada continuamente com água foram submetidos a treino de discriminação usando-se como estimulo discriminativo um breve choque elétrico. A seguir, usando-se o choque elétrico como reforçador condicionado, modelou-se a resposta de pressão ao trapézio por aproximações sucessivas, resultando em um encadeamento trapézio-choque-barra-àgua. Os resultados mostraram que quando se exige maior número de choques, para que uma resposta na barra seja reforçada, a resposta de pressão ao trapézio diminui em freqüência, o que pode ser explicado pela interação entre as propriedades aversiva e de reforço condicionado adquirida pelo choque elétrico. Os dados obtidos confirmam resultados anteriores que demonstram a aquisição de propriedades discriminativas por eventos aversivos e ampliam outros resultados da literatura mostrando que o comportamento pode ser mantido por estímulos aversivos dependendo do programa de sua apresentação.

Phase equilibrium conditions of semi-calthrate hydrates of (tetra-n-butyl ammonium chloride + carbon dioxide)

International Nuclear Information System (INIS)

Sun, Zhi-Gao; Jiao, Li-Jun; Zhao, Zhi-Gui; Wang, Gong-Liang; Huang, Hai-Feng

2014-01-01

Highlights: • Carbon dioxide hydrate stability zone was enlarged with the help of TBAC. • Carbon dioxide uptake into TBAC semi-clathrate hydrates is confirmed. • Equilibrium pressure of hydrate decreased with the increase of TBAC mass concentration. • The addition of TBAC reduces the formation pressures of carbon dioxide hydrate by 2.5 MPa. - Abstract: In the present work, hydrate equilibrium conditions for (tetra-n-butyl ammonium chloride (TBAC) + carbon dioxide + water) mixtures were investigated. Tetra-n-butyl ammonium chloride was reported to form a semi-clathrate hydrate. The experiments were carried out within the TBAC mass fraction range of (0.05 to 0.3). The experimental results showed that the presence of TBAC decreased the formation pressure of carbon dioxide double hydrate within the experimental temperature range. Moreover, pressure reduction was dependent on the TBAC concentration

Structure determination of a peptide model of the repeated helical domain in Samia cynthia ricini silk fibroin before spinning by a combination of advanced solid-state NMR methods.

Science.gov (United States)

Nakazawa, Yasumoto; Asakura, Tetsuo

2003-06-18

Fibrous proteins unlike globular proteins, contain repetitive amino acid sequences, giving rise to very regular secondary protein structures. Silk fibroin from a wild silkworm, Samia cynthia ricini, consists of about 100 repeats of alternating polyalanine (poly-Ala) regions of 12-13 residues in length and Gly-rich regions. In this paper, the precise structure of the model peptide, GGAGGGYGGDGG(A)(12)GGAGDGYGAG, which is a typical repeated sequence of the silk fibroin, was determined using a combination of three kinds of solid-state NMR studies; a quantitative use of (13)C CP/MAS NMR chemical shift with conformation-dependent (13)C chemical shift contour plots, 2D spin diffusion (13)C solid-state NMR under off magic angle spinning and rotational echo double resonance. The structure of the model peptide corresponding to the silk fibroin structure before spinning was determined. The torsion angles of the central Ala residue, Ala(19), in the poly-Ala region were determined to be (phi, psi) = (-59 degrees, -48 degrees ) which are values typically associated with alpha-helical structures. However, the torsion angles of the Gly(25) residue adjacent to the C-terminal side of the poly-Ala chain were determined to be (phi, psi) = (-66 degrees, -22 degrees ) and those of Gly(12) and Ala(13) residues at the N-terminal of the poly-Ala chain to be (phi, psi) = (-70 degrees, -30 degrees ). In addition, REDOR experiments indicate that the torsion angles of the two C-terminal Ala residues, Ala(23) and Ala(24), are (phi, psi) = (-66 degrees, -22 degrees ) and those of N-terminal two Ala residues, Ala(13) and Ala(14) are (phi, psi) = (-70 degrees, -30 degrees ). Thus, the local structure of N-terminal and C-terminal residues, and also the neighboring residues of alpha-helical poly-Ala chain in the model peptide is a more strongly wound structure than found in typical alpha-helix structures.

Tetra point wetting at the free surface of liquid Ga-Bi

International Nuclear Information System (INIS)

Huber, P.; Shpyrko, O.G.; Pershan, P.S.; Ocko, B.M.; Di Masi, E.; Deutsch, M.

2002-01-01

A continuous surface wetting transition, pinned to a solid-liquid-liquid-vapor tetra coexistence point, is studied by x-ray reflectivity in liquid Ga-Bi binary alloys. The short-range surface potential is determined from the measured temperature evolution of the wetting film. The thermal fluctuations are shown to be insufficient to induce a noticeable breakdown of mean-field behavior, expected in short-range-interacting systems due to their d u =3 upper critical dimensionality

Hydrogen bond controlled adduct formation of meso-tetra(4-sulfonatophenyl)porphyrin with protic acids: a UV-vis spectroscopic study.

Science.gov (United States)

Zakavi, Saeed; Rahiminezhad, Hajar; Alizadeh, Robabeh

2010-12-01

Interaction of meso-tetra(4-sulfonatophenyl)porphyrin (H2tppS4) with weak and strong protic acid have been studied by UV-vis spectroscopy in water, dichloromethane and methanol. Different shifts of the Soret and Q(0,0) bands in the three solvents, the aggregation of diprotonated species and the stability of porphyrin-acid adducts in the solution, may be explained by the inter- and intramolecular hydrogen bonds. Whilst, the addition of excess amounts of tetra-n-butylammonium chloride to H2tppS4(Cl)2 in dichloromethane has little to no effect on the UV-vis spectrum of the dication, gradual addition of tetra-n-butylammonium hydrogen sulfate to the dichloromethane solution of H2tppS4(H2SO4)2 leads to the degradation of adducts and the release of porphryin. The results of this study clearly show the crucial role played by hydrogen bonds between the porphyrin diprotonated species and the counter ion in the stability of porphyrin diacids in solution. Copyright © 2010 Elsevier B.V. All rights reserved.

Factores geométricos para calcular a flexión engranajes cilíndricos rectos asimétricos con perfil evolvente - trocoide // Geometric factors for determining the bending strength of asymmetric spur gears with profile teeth involute-trochoid

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Javier Antonio Cárdenas-Oliveros

2011-08-01

Full Text Available ResumenSe propone un modo de cálculo analítico basado en el análisis del modelo gráfico del diente de losengranajes cilíndricos rectos asimétricos con perfil de evolvente y trocoide, que permite obtener lasvariables asociadas a la determinación de los factores geométricos de forma y de resistencia,necesarios para el cálculo de la resistencia a flexión. Este tipo de procedimiento es empleado porprimera vez para obtener el parámetro geométrico de forma. Además, se establecen losfundamentos que aportan la determinación del parámetro geométrico de resistencia J para estostipos de engranajes. Los resultados de la presente investigación permiten determinar el esfuerzomáximo a la flexión a partir de los coeficientes geométricos de forma y resistencia, se construyeronecuaciones, tablas y diagramas representativos de estos parámetros. La aplicación práctica de esteenfoque de solución, permite la generalización del mismo en los mecanismos de transmisión conengranajes cilíndricos de dientes rectos asimétricos de perfil evolvente trocoide..Palabras claves: engranaje recto asimétrico, factores geométricos, resistencia a la flexión, CAD/CAE.__________________________________________________________________________AbstractIn this paper an analytical method of calculus based on computer analysis of the spur gears graphicmodel with asymmetric teeth of involute profile and trochoid is proposed, it was estimated formgeometry factor and bending strength by a direct calculus method. This procedure is first used toobtain form geometry factor. Furthermore, the factor J foundation for these types of gears wasestablished. The results of this research determinates analytically the maximum bending stress, usingthe form geometry factor and bending geometry factor, built equations, tables and diagramsrepresenting these parameters. The practical application of this solution approach allows thegeneralization of it in use in transmission

Boron-doped diamond electrodes for the electrochemical oxidation and cleavage of peptides.

Science.gov (United States)

Roeser, Julien; Alting, Niels F A; Permentier, Hjalmar P; Bruins, Andries P; Bischoff, Rainer

2013-07-16

Electrochemical oxidation of peptides and proteins is traditionally performed on carbon-based electrodes. Adsorption caused by the affinity of hydrophobic and aromatic amino acids toward these surfaces leads to electrode fouling. We compared the performance of boron-doped diamond (BDD) and glassy carbon (GC) electrodes for the electrochemical oxidation and cleavage of peptides. An optimal working potential of 2000 mV was chosen to ensure oxidation of peptides on BDD by electron transfer processes only. Oxidation by electrogenerated OH radicals took place above 2500 mV on BDD, which is undesirable if cleavage of a peptide is to be achieved. BDD showed improved cleavage yield and reduced adsorption for a set of small peptides, some of which had been previously shown to undergo electrochemical cleavage C-terminal to tyrosine (Tyr) and tryptophan (Trp) on porous carbon electrodes. Repeated oxidation with BDD electrodes resulted in progressively lower conversion yields due to a change in surface termination. Cathodic pretreatment of BDD at a negative potential in an acidic environment successfully regenerated the electrode surface and allowed for repeatable reactions over extended periods of time. BDD electrodes are a promising alternative to GC electrodes in terms of reduced adsorption and fouling and the possibility to regenerate them for consistent high-yield electrochemical cleavage of peptides. The fact that OH-radicals can be produced by anodic oxidation of water at elevated positive potentials is an additional advantage as they allow another set of oxidative reactions in analogy to the Fenton reaction, thus widening the scope of electrochemistry in protein and peptide chemistry and analytics.

Pathological assessment of farmed yellowtail tetra Astyanax altiparanae infested by Acusicola sp. (Ergasilidae

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Santiago Benites de Pádua

2015-11-01

Full Text Available This study registers for the first time the copepod Acusicola sp. infesting the gills of farmed yellowtail tetra Astyanax altiparanae, as well as new information on gross pathology and gill alterations. Five specimens of yellowtail tetra showing slow swimming, respiratory difficulty, scaleness and darkened skin were examined. Fish were analysed in situ for ectoparasites diagnosis. Fragments of the gill arches were removed and processed according to usual histopathology. The gills showed focal and multifocal paleness and whitish areas besides the congestion and hemorrhage signs on the gill filaments. Several white spots attached to the gill filament apex with slight movement were identified as the ergasilid crustacean. Histopathological analysis revealed the gill and blood vessels compression. It was also observed proliferative alterations close to gill filament apex, hyperplasia, total fusion and subepithelial oedema of the secondary lamellae, proliferation of the mucus cells, and inflammatory infiltrate by eosinophilic granular cells surrounding the parasite attachment region. The best management practices and the implementation of diagnostic program are also discussed.

Moessbauer spectroscopic characterisation of catalysts obtained by interaction between tetra-n-butyl-tin and silica or silica supported rhodium

International Nuclear Information System (INIS)

Millet, J.M.M.; Toyir, J.; Didillon, B.; Candy, J.P.; Nedez, C.; Basset, J.M.

1997-01-01

Moessbauer spectroscopy at 78 K was used to study the interaction between tetra-n-butyl-tin and the surfaces of silica or silica supported rhodium. At room temperature, the tetra-n-butyl-tin was physically adsorbed on the surfaces. After reaction under hydrogen at 373 K, the formation of grafted organometallic fragments on the Rh surface was confirmed whereas with pure silica, ≡SiO-Sn(n-C 4 H 9 ) 3 moieties were observed. After treatment at 523 K, the rhodium grafted organometallic species was completely decomposed and there was formation of a defined bimetallic RhSn compound

Serological profiling of the EBV immune response in Chronic Fatigue Syndrome using a peptide microarray.

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Madlen Loebel

Full Text Available Epstein-Barr-Virus (EBV plays an important role as trigger or cofactor for various autoimmune diseases. In a subset of patients with Chronic Fatigue Syndrome (CFS disease starts with infectious mononucleosis as late primary EBV-infection, whereby altered levels of EBV-specific antibodies can be observed in another subset of patients.We performed a comprehensive mapping of the IgG response against EBV comparing 50 healthy controls with 92 CFS patients using a microarray platform. Patients with multiple sclerosis (MS, systemic lupus erythematosus (SLE and cancer-related fatigue served as controls. 3054 overlapping peptides were synthesised as 15-mers from 14 different EBV proteins. Array data was validated by ELISA for selected peptides. Prevalence of EBV serotypes was determined by qPCR from throat washing samples.EBV type 1 infections were found in patients and controls. EBV seroarray profiles between healthy controls and CFS were less divergent than that observed for MS or SLE. We found significantly enhanced IgG responses to several EBNA-6 peptides containing a repeat sequence in CFS patients compared to controls. EBNA-6 peptide IgG responses correlated well with EBNA-6 protein responses. The EBNA-6 repeat region showed sequence homologies to various human proteins.Patients with CFS had a quite similar EBV IgG antibody response pattern as healthy controls. Enhanced IgG reactivity against an EBNA-6 repeat sequence and against EBNA-6 protein is found in CFS patients. Homologous sequences of various human proteins with this EBNA-6 repeat sequence might be potential targets for antigenic mimicry.

Níveis de alumínio e o desenvolvimento de porta-enxertos cítricos em cultivo hidropônico: I. Parâmetros biométricos

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Santos Carlos Henrique dos

1999-01-01

Full Text Available O presente trabalho teve como objetivo avaliar a influência de diferentes níveis de alumínio nos parâmetros biométricos dos porta-enxertos cítricos limoeiro Cravo e citrumeleiro Swingle em cultivo hidropônico. O experimento foi instalado em casa de vegetação em Botucatu, SP. Os tratamentos seguiram o delineamento estatístico inteiramente casualizado, com 3 repetições, em parcelas subdivididas. Os níveis de alumínio utilizados foram: 0; 7,5; 15; 22,5 e 30 mg L-1, na forma de AlCl3 6.H2O em solução nutritiva. Foram avaliados os parâmetros biométricos altura, número de folhas, diâmetro do caule, área foliar, comprimento e volume de raízes. De acordo com os resultados obtidos, conclui-se que o citrumeleiro Swingle apresentou-se mais sensível ao alumínio, sendo que, a partir de 7,5 mg L-1 houve redução nos valores destes parâmetros, enquanto que o limoeiro Cravo mostrou-se mais tolerante aos níveis de alumínio.

Volumetric properties of the (tetrahydrofuran + water) and (tetra-n-butyl ammonium bromide + water) systems: Experimental measurements and correlations

International Nuclear Information System (INIS)

Belandria, Veronica; Mohammadi, Amir H.; Richon, Dominique

2009-01-01

In this communication, we report experimental density data for the binary mixtures of (water + tetrahydrofuran) and (water + tetra-n-butyl ammonium bromide) at atmospheric pressure and various temperatures. The densities were measured using an Anton Paar TM digital vibrating-tube densimeter. For the (tetrahydrofuran + water) system, excess molar volumes have been calculated using the experimental densities and correlated using the Redlich-Kister equation. The Redlich-Kister equation parameters have been adjusted on experimental results. The partial molar volumes and partial excess molar volumes at infinite dilution have also been calculated for each component. A simple density equation was finally applied to correlate the measured density of the (tetra-n-butyl ammonium bromide + water) system.

Signal peptide cleavage is essential for surface expression of a regulatory T cell surface protein, leucine rich repeat containing 32 (LRRC32).

Science.gov (United States)

Chan, Derek V; Somani, Ally-Khan; Young, Andrew B; Massari, Jessica V; Ohtola, Jennifer; Sugiyama, Hideaki; Garaczi, Edina; Babineau, Denise; Cooper, Kevin D; McCormick, Thomas S

2011-05-26

Elevated numbers of regulatory T cells (T(regs)) have been implicated in certain cancers. Depletion of T(regs) has been shown to increase anti-tumor immunity. T(regs) also play a critical role in the suppression of autoimmune responses. The study of T(regs) has been hampered by a lack of adequate surface markers. Leucine Rich Repeat Containing 32 (LRRC32), also known as Glycoprotein A Repetitions Predominant (GARP), has been postulated as a novel surface marker of activated T(regs). However, there is limited information regarding the processing of LRRC32 or the regulatory phenotype and functional activity of T(regs) expressing LRRC32. Using naturally-occurring freshly isolated T(regs), we demonstrate that low levels of LRRC32 are present intracellularly prior to activation and that freshly isolated LRRC32+ T(regs) are distinct from LRRC32- T(regs) with respect to the expression of surface CD62L. Using LRRC32 transfectants of HEK cells, we demonstrate that the N-terminus of LRRC32 is cleaved prior to expression of the protein at the cell surface. Furthermore, we demonstrate using a construct containing a deleted putative signal peptide region that the presence of a signal peptide region is critical to cell surface expression of LRRC32. Finally, mixed lymphocyte assays demonstrate that LRRC32+ T(regs) are more potent suppressors than LRRC32- T(regs). A cleaved signal peptide site in LRRC32 is necessary for surface localization of native LRRC32 following activation of naturally-occurring freshly-isolated regulatory T cells. LRRC32 expression appears to alter the surface expression of activation markers of T cells such as CD62L. LRRC32 surface expression may be useful as a marker that selects for more potent T(reg) populations. In summary, understanding the processing and expression of LRRC32 may provide insight into the mechanism of action of T(regs) and the refinement of immunotherapeutic strategies aimed at targeting these cells.

Signal peptide cleavage is essential for surface expression of a regulatory T cell surface protein, leucine rich repeat containing 32 (LRRC32

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Sugiyama Hideaki

2011-05-01

Full Text Available Abstract Background Elevated numbers of regulatory T cells (Tregs have been implicated in certain cancers. Depletion of Tregs has been shown to increase anti-tumor immunity. Tregs also play a critical role in the suppression of autoimmune responses. The study of Tregs has been hampered by a lack of adequate surface markers. Leucine Rich Repeat Containing 32 (LRRC32, also known as Glycoprotein A Repetitions Predominant (GARP, has been postulated as a novel surface marker of activated Tregs. However, there is limited information regarding the processing of LRRC32 or the regulatory phenotype and functional activity of Tregs expressing LRRC32. Results Using naturally-occurring freshly isolated Tregs, we demonstrate that low levels of LRRC32 are present intracellularly prior to activation and that freshly isolated LRRC32+ Tregs are distinct from LRRC32- Tregs with respect to the expression of surface CD62L. Using LRRC32 transfectants of HEK cells, we demonstrate that the N-terminus of LRRC32 is cleaved prior to expression of the protein at the cell surface. Furthermore, we demonstrate using a construct containing a deleted putative signal peptide region that the presence of a signal peptide region is critical to cell surface expression of LRRC32. Finally, mixed lymphocyte assays demonstrate that LRRC32+ Tregs are more potent suppressors than LRRC32- Tregs. Conclusions A cleaved signal peptide site in LRRC32 is necessary for surface localization of native LRRC32 following activation of naturally-occurring freshly-isolated regulatory T cells. LRRC32 expression appears to alter the surface expression of activation markers of T cells such as CD62L. LRRC32 surface expression may be useful as a marker that selects for more potent Treg populations. In summary, understanding the processing and expression of LRRC32 may provide insight into the mechanism of action of Tregs and the refinement of immunotherapeutic strategies aimed at targeting these cells.

Multi-criteria analysis and systemic planning: Towards a tetra-logical approach to planning and assessment

DEFF Research Database (Denmark)

Leleur, Steen

This paper presents systemic planning (SP) with emphasis on multi-criteria decision analysis (MCDA). Specifically, SP is presented as a “tetra-logical” methodology approach with MCDA as one out of four major method orientations. The Danish-Swedish Øresund Fixed Link is used as application example...

Antibody reactivities to glutamate-rich peptides of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

DEFF Research Database (Denmark)

Jakobsen, P.H.; Theander, T.G.; Hvid, L

1996-01-01

Synthetic P. falciparum peptides were evaluated as tools in epidemiological investigations of malaria. Plasma IgM and IgG antibody reactivities against synthetic peptides covering sequences of glutamate-rich protein (GLURP) and acidic-basic repeat antigen (ABRA) were measured by ELISA...

Are there evidences for the influence of GSM- and TETRA-electromagnetic fields on language comprehension in the human memory?; Laesst sich durch den Einfluss von kopfnah gepulsten Hochfrequenzfeldern des GSM- und TETRA-Mobilfunks ein Wirkungseffekt auf sprachverarbeitende Prozesse im Gedaechtnis nachweisen?

Energy Technology Data Exchange (ETDEWEB)

Kaul, G. [Bundesanstalt fuer Arbeitsschutz und Arbeitsmedizin, Berlin (Germany); Stummvoll, B.; Beyer, R. [Humboldt-Universitaet, Berlin (Germany). Institut fuer Psychologie

2004-07-01

The experimental study using a double blind design examining the influences of the electromagnetic fields of GSM and TETRA mobile phones on the language comprehension in the human memory. 30 young men had to decide whether a given word was contained in a text they had read before. It will be demonstrated that GSM-radiation seemed to cause a quicker answer. In contrast the TETRA-radiation allowed reading - i.e. to understand - the text in a significant shorter time when the exposition came from the telephone situated on the right side of the head. Since these effects are very small, there is now evidence for a health risk. Both results point at a support of the mental processes at attention and memory. (orig.)

Historia del experimento barométrico

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Rosa María Herrera

2012-04-01

Full Text Available Ciertos problemas hidráulicos planteados por el ingeniero Baliani hacía 1630 culminaron en el experimento barométrico realizado por el matemático Torricelli en 1644. Este último, ferviente galileano, pensaba la matemática como lenguaje con que la naturaleza habla a los hombres. Con este soporte teórico del mundo realizó un experimento físico con el que calibró la presión atmosférica y comprobó la existencia del vacío.

Peptide chemistry toolbox - Transforming natural peptides into peptide therapeutics.

Science.gov (United States)

Erak, Miloš; Bellmann-Sickert, Kathrin; Els-Heindl, Sylvia; Beck-Sickinger, Annette G

2018-06-01

The development of solid phase peptide synthesis has released tremendous opportunities for using synthetic peptides in medicinal applications. In the last decades, peptide therapeutics became an emerging market in pharmaceutical industry. The need for synthetic strategies in order to improve peptidic properties, such as longer half-life, higher bioavailability, increased potency and efficiency is accordingly rising. In this mini-review, we present a toolbox of modifications in peptide chemistry for overcoming the main drawbacks during the transition from natural peptides to peptide therapeutics. Modifications at the level of the peptide backbone, amino acid side chains and higher orders of structures are described. Furthermore, we are discussing the future of peptide therapeutics development and their impact on the pharmaceutical market. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dimensionado y Tolerado Geométrico en las Normas Técnicas Colombianas

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Jorge Gómez

2002-01-01

Full Text Available En este artículo se hace una introducción al tema del Dimensionado y Tolerado Geométrico mostrando una comparación con el sistema de Tolerado Convencional y se destacan algunas de sus ventajas. Posteriormente describe seis tipos de error de frecuente ocurrencia en las Normas Técnicas Colombianas -NTC- sobre Dimensionado y Tolerado Geométrico. Se menciona el número de veces aproximado que estos tipos de errores se presentan en cada norma. Finalmente se aborda una discusión y se hace alusión a las posibles consecuencias que en el país se dan con la existencia de estas normas en su condición actual

Quality of tri-Co-60 MR-IGRT treatment plans in comparison with VMAT treatment plans for spine SABR.

Science.gov (United States)

Choi, Chang Heon; Park, So-Yeon; Kim, Jung-In; Kim, Jin Ho; Kim, Kyubo; Carlson, Joel; Park, Jong Min

2017-02-01

To investigate the plan quality of tri-Co-60 intensity-modulated radiation therapy (IMRT) plans for spine stereotactic ablative radiotherapy (SABR). A total of 20 patients with spine metastasis were retrospectively selected. For each patient, a tri-Co-60 IMRT plan and a volumetric-modulated arc therapy (VMAT) plan were generated. The spinal cords were defined based on MR images for the tri-Co-60 IMRT, while isotropic 1-mm margins were added to the spinal cords for the VMAT plans. The VMAT plans were generated with 10-MV flattening filter-free photon beams of TrueBeam STx ™ (Varian Medical Systems, Palo Alto, CA), while the tri-Co-60 IMRT plans were generated with the ViewRay ™ system (ViewRay inc., Cleveland, OH). The initial prescription dose was 18 Gy (1 fraction). If the tolerance dose of the spinal cord was not met, the prescription dose was reduced until the spinal cord tolerance dose was satisfied. The mean dose to the target volumes, conformity index and homogeneity index of the VMAT and tri-Co-60 IMRT were 17.8 ± 0.8 vs 13.7 ± 3.9 Gy, 0.85 ± 0.20 vs 1.58 ± 1.29 and 0.09 ± 0.04 vs 0.24 ± 0.19, respectively. The integral doses and beam-on times were 16,570 ± 1768 vs 22,087 ± 2.986 Gy cm 3 and 3.95 ± 1.13 vs 48.82 ± 10.44 min, respectively. The tri-Co-60 IMRT seems inappropriate for spine SABR compared with VMAT. Advances in knowledge: For spine SABR, the tri-Co-60 IMRT is inappropriate owing to the large penumbra, large leaf width and low dose rate of the ViewRay system.

Rhinusa Stephens: a taxonomic revision of the species belonging to the R. tetra and R. bipustulata groups (Coleoptera Curculionidae

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Roberto Caldara

2014-10-01

Full Text Available The species of Rhinusa Stephens, 1829 (Curculionidae, Curculioninae, Mecinini belonging to the R. tetra and R. bipustulata groups are revised. Four of them from Middle East are new to science. The R. bipustulata group includes five species: R. bipustulata (Rossi, 1792; R. pelletieri sp. nov.; R. scrophulariae Caldara, 2009; R. algirica (Brisout de Barneville, 1862; R. emmrichi (Bajtenov, 1979, whereas the R. tetra group includes nine species: R. tetra (Fabricius, 1792; R. verbasci (Rosenschoeld, 1838; R. ensifer sp. nov.; R. moroderi (Reitter, 1906; R. weilli sp. nov.; R. comosa (Rosenschoeld, 1838; R. acifer sp. nov.; R asellus (Gravenhorst, 1807; R. tenuirostris (Stierlin, 1888. The following new synonym is proposed: Rhinusa bipustulata (Rossi, 1792 (= Gymnetron municipale Voss, 1960 syn. nov.. The neotype of Rhynchaenus asellus Gravenhorst, 1807 was designated. Moreover, the following lectotypes are designated: Cionus spilotus Germar, 1821; Gymnetron bipustulatum var. germari Faust, 1889; Gymnetron bodenheimeri Wagner, 1926; Gymnetron cylindrirostre Gyllenhal, 1838; Gymnetron nasutum Rosenschoeld, 1838; Gymnetron plagiatum Gyllenhal, 1838; Gymnetron polonicum Rosenschoeld, 1838; Gymnetron tenuirostre Stierlin, 1888. A key to the species, diagnoses of species groups, descriptions or redescriptions, notes on type specimens, synonymies, comparative notes, distribution, bionomics when available, photographs of habitus and drawings of rostra, terminalia and other useful characters for taxonomy are provided.

Electron spin resonance signal from a tetra-interstitial defect in silicon

CERN Document Server

Mchedlidze, T

2003-01-01

The Si-B3 electron spin resonance (ESR) signal from agglomerates of self-interstitials was detected for the first time in hydrogen-doped float-zone-grown silicon samples subjected to annealing after electron irradiation. Previously this signal had been detected only in neutron- or proton-irradiated silicon samples. The absence of obscuring ESR peaks for the investigated samples at applied measurement conditions allowed an investigation of the hyperfine structure of the Si-B3 spectra. The analysis supports assignment of a tetra-interstitial defect as the origin of the signal.

α-Peptide/ß-Peptoid Chimeras

DEFF Research Database (Denmark)

Olsen, Christian Adam; Bonke, Gitte; Vedel, Line

2007-01-01

We describe the synthesis and characterization of the first generation of oligomers consisting of alternating repeats of a-amino acids and chiral N-alkyl-ß-alanine (ß-peptoid) residues. These chimeras are stable toward proteolysis, non-hemolytic, and possess antibacterial activity comparable...... to well-known antimicrobial agents. Moreover, the chimeras exhibit length-dependent, concentration-dependent, solvent-dependent, and ion-strength-dependent ellipticity, indicating the presence of a secondary structure in solution. Thus, a-peptide/ß-peptoid oligomers represent a promising novel...

Identification and characterization of short tandem repeats in the Tibetan macaque genome based on resequencing data.

Science.gov (United States)

Liu, San-Xu; Hou, Wei; Zhang, Xue-Yan; Peng, Chang-Jun; Yue, Bi-Song; Fan, Zhen-Xin; Li, Jing

2018-07-18

The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature (IUCN). Short tandem repeats (STRs) refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software (lobSTR), we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals (Pgenome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.

Aspectos biométricos do desenvolvimento testicular e corporal em cutias (Dasyprocta aguti criadas em cativeiros

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Antônio Chaves de Assis-Neto

2003-01-01

Full Text Available Analisou-se os dados biométricos do desenvolvimento testicular e peso corporal de 31 cutias (Dasyprocta aguti desde o nascimento até os 14 meses de idade. As correlações entre o peso corporal, idade e parâmetros testiculares apresentaram-se altamente significativas. O peso testicular, o volume testicular, assim como os demais parâmetros biométricos testiculares (comprimento, diâmetro e perímetro, evoluíram lenta e gradualmente até os 8 meses de idade. A partir dos 9 meses, o crescimento foi mais rápido. O desenvolvimento biométrico do testículo pode ser dividido em duas fases, de 0 - 8 meses e de 9 - 14 meses de idade, sendo 9 meses considerado ponto de corte em se tratando de desenvolvimento testicular de cutias criadas em cativeiro.

Multimerized CHR-derived peptides as HIV-1 fusion inhibitors.

Science.gov (United States)

Nomura, Wataru; Hashimoto, Chie; Suzuki, Takaharu; Ohashi, Nami; Fujino, Masayuki; Murakami, Tsutomu; Yamamoto, Naoki; Tamamura, Hirokazu

2013-08-01

To date, several HIV-1 fusion inhibitors based on the carboxy-terminal leucine/isoleucine heptad repeat (CHR) region of an HIV-1 envelope protein gp41 have been discovered. We have shown that a synthetic peptide mimetic of a trimer form of the CHR-derived peptide C34 has potent inhibitory activity against the HIV-1 fusion mechanism, compared to a monomer C34 peptide. The present study revealed that a dimeric form of C34 is evidently structurally critical for fusion inhibitors, and that the activity of multimerized CHR-derived peptides in fusion inhibition is affected by the properties of the unit peptides C34, SC34EK, and T20. The fluorescence-based study suggested that the N36-interactive sites of the C34 trimer, including hydrophobic residues, are exposed outside the trimer and that trimerization of C34 caused a remarkable increase in fusion inhibitory activity. The present results could be useful in the design of fusion inhibitors against viral infections which proceed via membrane fusion with host cells. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Poly-dipeptides encoded by the C9ORF72 repeats block global protein translation.

Science.gov (United States)

Kanekura, Kohsuke; Yagi, Takuya; Cammack, Alexander J; Mahadevan, Jana; Kuroda, Masahiko; Harms, Matthew B; Miller, Timothy M; Urano, Fumihiko

2016-05-01

The expansion of the GGGGCC hexanucleotide repeat in the non-coding region of the Chromosome 9 open-reading frame 72 (C9orf72) gene is the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). This genetic alteration leads to the accumulation of five types of poly-dipeptides translated from the GGGGCC hexanucleotide repeat. Among these, poly-proline-arginine (poly-PR) and poly-glycine-arginine (poly-GR) peptides are known to be neurotoxic. However, the mechanisms of neurotoxicity associated with these poly-dipeptides are not clear. A proteomics approach identified a number of interacting proteins with poly-PR peptide, including mRNA-binding proteins, ribosomal proteins, translation initiation factors and translation elongation factors. Immunostaining of brain sections from patients with C9orf72 ALS showed that poly-GR was colocalized with a mRNA-binding protein, hnRNPA1. In vitro translation assays showed that poly-PR and poly-GR peptides made insoluble complexes with mRNA, restrained the access of translation factors to mRNA, and blocked protein translation. Our results demonstrate that impaired protein translation mediated by poly-PR and poly-GR peptides plays a role in neurotoxicity and reveal that the pathways altered by the poly-dipeptides-mRNA complexes are potential therapeutic targets for treatment of C9orf72 FTD/ALS. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Hiperprolactinemia e distúrbios psiquiátricos Hyperprolactinemia and psychological disturbance

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MIRIAM C. OLIVEIRA

2000-09-01

Full Text Available Sintomas psicológicos, especialmente ansiedade e depressão, têm sido associados à hiperprolactinemia. Para avaliar a presença desses sintomas, foram submetidos à entrevista através do Composed International Diagnostic Interview, seguido pela escala de Hamilton para depressão, 32 pacientes (5 homens e 27 mulheres com hiperprolactinemia de várias etiologias e 16 normoprolactinêmicos. A prolactina sérica na época da avaliação variou de 28 a 180 ng/mL, sendo que 11 dos pacientes usavam bromocriptina. Detectou-se presença atual de distúrbios de ansiedade em 18 pacientes (56,2% e 5 controles (31,2%, depressão em 10 pacientes (31,2% e 2 controles (12,5%, distmia em duas pacientes e outros diagnósticos psiquiátricos em 6 pacientes (18,7%. Os escores da depressão variaram entre 16 e 31 nos pacientes e foram 12 e 16 nos controles. A frequência de sintomas psiquiátricos como um todo, foi significativamente maior nos hiperprolactinêmicos (teste do qui-quadrado, mas a diferença não foi significativa na análise isolada de ansiedade ou depressão. A hiperprolactinemia representa um fator de risco de 3,57 para depressão, 3,32 para ansiedade e 3,84 para outros sintomas psiquiátricos. Não houve diferença significativa na frequência de sintomas psiquiátricos entre portadores ou não de adenomas hipofisários e usuários ou não de bromocriptina. Não houve correlação (r= 0,07 entre a prolactina e a frequência de sintomas psiquiátricos. Conclui-se pela necessidade de atentar para a concomitância de hiperprolactinemia e distúrbios psiquiátricos, cujo reconhecimento permitirá abordagem terapêutica específica.Psychological symptoms, specially anxiety and depression, have been associated to hyperprolactinemia. To evaluate the presence of these symptoms, 32 patients (5 men and 27 women with hyperprolactinemia of several etiologies and 15 individuals with normal prolactin levels were submitted to the Composed International

CLASSIFICAÇÃO DE PACIENTES PEDIÁTRICOS EM UM HOSPITAL DE ENSINO DE TERESINA

OpenAIRE

Márcia Teles de Oliveira Gouveia; Mônica Cristiane Soares Mendes; Yaciara Pereira de Oliveira Luz; Grazielle Roberta Freitas da Silva

2010-01-01

La evaluación minuciosa del estado físico/emocional y el grado de dependencia de enfermería de los niños pueden respaldar una buena planificación de la asistencia, lo cual es posible por medio de sistemas de clasificación. El objetivo fue clasificar y evaluar pacientes pediátricos según el Instrumento de Clasificación de Pacientes Pediátricos (ICPP) y su nivel de dependencia en relación al cuidado de enfermería. Es un estudio descriptivo y exploratorio, con enfoque cuantitativo, realizado en ...

Surface chemistry and electrocatalytic behaviour of tetra-carboxy substituted iron, cobalt and manganese phthalocyanine monolayers on gold electrode

International Nuclear Information System (INIS)

Mashazi, Philani N.; Westbroek, Philippe; Ozoemena, Kenneth I.; Nyokong, Tebello

2007-01-01

Surface chemistry and electrocatalytic properties of self-assembled monolayers of metal tetra-carboxylic acid phthalocyanine complexes with cobalt (Co), iron (Fe) and manganese (Mn) as central metal ions have been studied. These phthalocyanine molecules are immobilized on gold electrode via the coupling reaction between the ring substituents and pre-formed mercaptoethanol self-assembled monolayer (Au-ME SAM). X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy confirmed chemisorption of mercaptoethanol via sulfur group on gold electrode and also coupling reaction between phthalocyanines and Au-ME SAM. Electrochemical parameters of the immobilized molecules show that these molecules are densely packed with a perpendicular orientation. The potential applications of the gold modified electrodes were investigated towards L-cysteine detection and the analysis at phthalocyanine SAMs. Cobalt and iron tetra-carboxylic acid phthalocyanine monolayers showed good oxidation peak for L-cysteine at potentials where metal oxidation (M III /M II ) takes place and this metal oxidation mediates the catalytic oxidation of L-cysteine. Manganese tetra-carboxylic acid phthalocyanine monolayer also exhibited a good catalytic oxidation peak towards L-cysteine at potentials where Mn IV /Mn III redox peak occurs and this redox peak mediates L-cysteine oxidation. The analysis of cysteine at phthalocyanine monolayers displayed good analytical parameters with good detection limits of the orders of 10 -7 mol L -1 and good linearity for a studied concentration range up to 60 μmol L -1

Molecular characterization of long direct repeat (LDR) sequences expressing a stable mRNA encoding for a 35-amino-acid cell-killing peptide and a cis-encoded small antisense RNA in Escherichia coli.

Science.gov (United States)

Kawano, Mitsuoki; Oshima, Taku; Kasai, Hiroaki; Mori, Hirotada

2002-07-01

Genome sequence analyses of Escherichia coli K-12 revealed four copies of long repetitive elements. These sequences are designated as long direct repeat (LDR) sequences. Three of the repeats (LDR-A, -B, -C), each approximately 500 bp in length, are located as tandem repeats at 27.4 min on the genetic map. Another copy (LDR-D), 450 bp in length and nearly identical to LDR-A, -B and -C, is located at 79.7 min, a position that is directly opposite the position of LDR-A, -B and -C. In this study, we demonstrate that LDR-D encodes a 35-amino-acid peptide, LdrD, the overexpression of which causes rapid cell killing and nucleoid condensation of the host cell. Northern blot and primer extension analysis showed constitutive transcription of a stable mRNA (approximately 370 nucleotides) encoding LdrD and an unstable cis-encoded antisense RNA (approximately 60 nucleotides), which functions as a trans-acting regulator of ldrD translation. We propose that LDR encodes a toxin-antitoxin module. LDR-homologous sequences are not pre-sent on any known plasmids but are conserved in Salmonella and other enterobacterial species.

Detection and quantitative characterization of artificial extra peaks following polymerase chain reaction amplification of 14 short tandem repeat systems used in forensic investigations

DEFF Research Database (Denmark)

Meldgaard, Michael; Morling, N

1997-01-01

Detection on automated DNA sequencers of polymerase chain reaction (PCR) products of tetra- and penta-nucleotide short tandem repeat (STR) loci frequently reveals one or more extra peaks along with the true, major allele peak. The most frequent extra peak pattern is a single smaller peak which...... is one repeat unit shorter than the true allele peak. The existence of such artificial peaks is of special importance when the methods are used for forensic investigations because the artificial extra peaks may simulate true alleles when samples containing mixtures of DNA from different individuals...... are analyzed. We have investigated the relative levels of formation of extra peaks in 14 STR marker systems. We found that not only the parameters of the PCR but also factors determining the stringency during the post-PCR and pre-electrophoresis handling of samples were of importance for the formation of extra...

Repeated measurements of NT-pro-B-type natriuretic peptide, troponin T or C-reactive protein do not predict future allograft rejection in heart transplant recipients.

Science.gov (United States)

Battes, Linda C; Caliskan, Kadir; Rizopoulos, Dimitris; Constantinescu, Alina A; Robertus, Jan L; Akkerhuis, Martijn; Manintveld, Olivier C; Boersma, Eric; Kardys, Isabella

2015-03-01

Studies on the prognostic value of serial biomarker assays for future occurrence of allograft rejection (AR) are scarce. We examined whether repeated measurements of NT-pro-B-type natriuretic peptide (NT-proBNP), troponin T (TropT) and C-reactive protein (CRP) predict AR. From 2005 to 2010, 77 consecutive heart transplantation (HTx) recipients were included. The NT-proBNP, TropT, and CRP were measured at 16 ± 4 (mean ± standard deviation) consecutive routine endomyocardial biopsy surveillance visits during the first year of follow-up. Allograft rejection was defined as International Society for Heart and Lung Transplantation (ISHLT) grade 2R or higher at endomyocardial biopsy. Joint modeling was used to assess the association between repeated biomarker measurements and occurrence of future AR. Joint modeling accounts for dependence among repeated observations in individual patients. The mean age of the patients at HTx was 49 ± 9.2 years, and 68% were men. During the first year of follow-up, 1,136 biopsies and concurrent blood samples were obtained, and 56 patients (73%) experienced at least one episode of AR. All biomarkers were elevated directly after HTx and achieved steady-state after ∼ 12 weeks, both in patients with or without AR. No associations were present between the repeated measurements of NT-proBNP, TropT, or CRP and AR both early (weeks 0-12) and late (weeks 13-52) in the course after HTx (hazard ratios for weeks 13-52: 0.96 (95% confidence interval, 0.55-1.68), 0.67 (0.27-1.69), and 1.44 (0.90-2.30), respectively, per ln[unit]). Combining the three biomarkers in one model also rendered null results. The temporal evolution of NT-proBNP, TropT, and CRP before AR did not predict occurrence of acute AR both in the early and late course of the first year after HTx.

Trasplante cardíaco pediátrico: pasado, presente y futuro

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María-Teresa González-López

2017-01-01

Conclusión: El trasplante cardíaco pediátrico presenta óptimos resultados en nuestro medio, superponibles a series mundiales. Aunque el perfil de riesgo está incrementándose, los resultados actuales reflejan los avances en el manejo de estos pacientes.

Sensitivity of photoelectron diffraction to conformational changes of adsorbed molecules: Tetra-tert-butyl-azobenzene/Au(111

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A. Schuler

2017-01-01

Full Text Available Electron diffraction is a standard tool to investigate the atomic structure of surfaces, interfaces, and adsorbate systems. In particular, photoelectron diffraction is a promising candidate for real-time studies of structural dynamics combining the ultimate time resolution of optical pulses and the high scattering cross-sections for electrons. In view of future time-resolved experiments from molecular layers, we studied the sensitivity of photoelectron diffraction to conformational changes of only a small fraction of molecules in a monolayer adsorbed on a metallic substrate. 3,3′,5,5′-tetra-tert-butyl-azobenzene served as test case. This molecule can be switched between two isomers, trans and cis, by absorption of ultraviolet light. X-ray photoelectron diffraction patterns were recorded from tetra-tert-butyl-azobenzene/Au(111 in thermal equilibrium at room temperature and compared to patterns taken in the photostationary state obtained by exposing the surface to radiation from a high-intensity helium discharge lamp. Difference patterns were simulated by means of multiple-scattering calculations, which allowed us to determine the fraction of molecules that underwent isomerization.

ACCA phosphopeptide recognition by the BRCT repeats of BRCA1.

Science.gov (United States)

Ray, Hind; Moreau, Karen; Dizin, Eva; Callebaut, Isabelle; Venezia, Nicole Dalla

2006-06-16

The tumour suppressor gene BRCA1 encodes a 220 kDa protein that participates in multiple cellular processes. The BRCA1 protein contains a tandem of two BRCT repeats at its carboxy-terminal region. The majority of disease-associated BRCA1 mutations affect this region and provide to the BRCT repeats a central role in the BRCA1 tumour suppressor function. The BRCT repeats have been shown to mediate phospho-dependant protein-protein interactions. They recognize phosphorylated peptides using a recognition groove that spans both BRCT repeats. We previously identified an interaction between the tandem of BRCA1 BRCT repeats and ACCA, which was disrupted by germ line BRCA1 mutations that affect the BRCT repeats. We recently showed that BRCA1 modulates ACCA activity through its phospho-dependent binding to ACCA. To delineate the region of ACCA that is crucial for the regulation of its activity by BRCA1, we searched for potential phosphorylation sites in the ACCA sequence that might be recognized by the BRCA1 BRCT repeats. Using sequence analysis and structure modelling, we proposed the Ser1263 residue as the most favourable candidate among six residues, for recognition by the BRCA1 BRCT repeats. Using experimental approaches, such as GST pull-down assay with Bosc cells, we clearly showed that phosphorylation of only Ser1263 was essential for the interaction of ACCA with the BRCT repeats. We finally demonstrated by immunoprecipitation of ACCA in cells, that the whole BRCA1 protein interacts with ACCA when phosphorylated on Ser1263.

ISOLAMENTO TÉRMICO DE RESIDÊNCIAS ATRAVÉS DA REUTILIZAÇÃO DE EMBALAGENS TETRA PAK

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Jaquiel Salvi Fernandes

2014-09-01

Full Text Available A reciclagem está presente na atualidade, não apenas pelo aspecto econômico, mas também pela questão ambiental. Não faz sentido jogar junto com o lixo orgânico materiais que possam ser reaproveitados ou transformados. Neste contexto também se encontram as embalagens de leite e/ou suco longa vida (Tetra Pak®, amplamente utilizadas pela população. Tais embalagens têm baixo valor comercial, e sua reciclagem é difícil e de custo muito elevado. Este trabalho de extensão universitária reutilizou estas embalagens, montando painéis com as dimensões do forro de residências selecionadas na cidade de Videira-SC, com o intuito de isolá-las termicamente. As caixinhas Tetra Pak possuem uma face aluminizada, a qual impede que o calor seja transmitido para o interior (ou exterior no caso do inverno da residência pelo processo de radiação, refletindo mais de 95% do calor. Com esta característica a caixa de leite se mostra perfeita para exercer a função de manta térmica, como uma alternativa às mantas convencionais, com a vantagem de ser uma solução ecológica e barata. Após a instalação, as casas que antes não possuíam forro passaram a registrar temperaturas internas menores no verão e maiores no inverno, além da prevenção contra goteiras e respingos. As famílias atendidas expressaram unanimidade de opinião, mostrando-se muito satisfeitas com o ambiente após a instalação, relatando o aumento da temperatura em dias mais frios e sua diminuição em dias mais quentes. Palavras-chave: painéis térmicos, reutilização, embalagens longa vida, extensão universitária. Thermal isolation of residences through reuse of Tetra Pak packaging Abstract: Nowadays recycling is present not only in economic but also in environmental issues. It makes no sense mixing together with organic waste the materials that can be reused or processed. Milk and long life juice cartons (Tetra Pak®, widely used by the population, are also included

Degradation Behavior and Accelerated Weathering of Composite Boards Produced from Waste Tetra Pak® Packaging Materials

Science.gov (United States)

Nural Yilgor; Coskun Kose; Evren Terzi; Aysel Kanturk Figen; Rebecca Ibach; S. Nami Kartal; Sabriye Piskin

2014-01-01

Manufacturing panels from Tetra Pak® (TP) packaging material might be an alternative to conventional wood-based panels. This study evaluated some chemical and physical properties as well as biological, weathering, and fire performance of panels with and without zinc borate (ZnB) by using shredded TP packaging cartons. Such packaging material, a worldwide well-known...

Human lactoferricin derived di-peptides deploying loop structures induce apoptosis specifically in cancer cells through targeting membranous phosphatidylserine.

Science.gov (United States)

Riedl, Sabrina; Leber, Regina; Rinner, Beate; Schaider, Helmut; Lohner, Karl; Zweytick, Dagmar

2015-11-01

Host defense-derived peptides have emerged as a novel strategy for the development of alternative anticancer therapies. In this study we report on characteristic features of human lactoferricin (hLFcin) derivatives which facilitate specific killing of cancer cells of melanoma, glioblastoma and rhabdomyosarcoma compared with non-specific derivatives and the synthetic peptide RW-AH. Changes in amino acid sequence of hLFcin providing 9-11 amino acids stretched derivatives LF11-316, -318 and -322 only yielded low antitumor activity. However, the addition of the repeat (di-peptide) and the retro-repeat (di-retro-peptide) sequences highly improved cancer cell toxicity up to 100% at 20 μM peptide concentration. Compared to the complete parent sequence hLFcin the derivatives showed toxicity on the melanoma cell line A375 increased by 10-fold and on the glioblastoma cell line U-87mg by 2-3-fold. Reduced killing velocity, apoptotic blebbing, activation of caspase 3/7 and formation of apoptotic DNA fragments proved that the active and cancer selective peptides, e.g. R-DIM-P-LF11-322, trigger apoptosis, whereas highly active, though non-selective peptides, such as DIM-LF11-318 and RW-AH seem to kill rapidly via necrosis inducing membrane lyses. Structural studies revealed specific toxicity on cancer cells by peptide derivatives with loop structures, whereas non-specific peptides comprised α-helical structures without loop. Model studies with the cancer membrane mimic phosphatidylserine (PS) gave strong evidence that PS only exposed by cancer cells is an important target for specific hLFcin derivatives. Other negatively charged membrane exposed molecules as sialic acid, heparan and chondroitin sulfate were shown to have minor impact on peptide activity. Copyright © 2015. Published by Elsevier B.V.

Análise do campo elétrico atmosférico durante tempo bom e distúrbios geofísicos

OpenAIRE

Anaya, José Carlos Tacza

2015-01-01

Neste trabalho de dissertação apresenta-se a capabilidade de uma nova rede de sensores para monitorar o campo elétrico atmosférico em vários locais na América do Sul. O objetivo principal é obter a curva diária do campo elétrico atmosférico de tempo bom. Para isto foram realizadas médias mensais, sazonais e anuais. Essa curva é comparada com a curva característica em Tempo Universal conhecida como a Curva de Carnegie, a qual é relacionada com as correntes fluindo no Circuito Elétrico Atmosfér...

Análisis de propulsión iónica en condensadores asimétricos

OpenAIRE

Cubides Alfonso, Fredy Yamith; Lancheros Quiroga, David Leonardo; Chacón-Cardona, César Alexander

2016-01-01

Resumen Presenta una nueva metodología para el estudio del comportamiento en condensadores asimétricos del fenómeno de levitación electromagnética, sometido a altas tensiones (AC y DC). Se realizaron modelos experimentales para un análisis cinemático y simulaciones para observar el campo eléctrico y magnético, y, por último, se hicieron estudios de termografía de los condensadores asimétricos, con el fin de realizar un análisis cuantitativo y cualitativo del fenómeno de levitación electromagn...

Characterization of melanocortin NDP-MSH agonist peptide fragments at the mouse central and peripheral melanocortin receptors.

Science.gov (United States)

Haskell-Luevano, C; Holder, J R; Monck, E K; Bauzo, R M

2001-06-21

The central melanocortin receptors, melanocortin-4 (MC4R) and melanocortin-3 (MC3R), are involved in the regulation of satiety and energy homeostasis. The MC4R in particular has become a pharmaceutical industry drug target due to its direct involvement in the regulation of food intake and its potential therapeutic application for the treatment of obesity-related diseases. The melanocortin receptors are stimulated by the native ligand, alpha-melanocyte stimulating hormone (alpha-MSH). The potent and enzymatically stable analogue NDP-MSH (Ac-Ser-Tyr-Ser-Nle-Glu-His-DPhe-Arg-Trp-Gly-Lys-Pro-Val-NH(2)) is a lead peptide for the identification of melanocortin amino acids important for receptor molecular recognition and stimulation. We have synthesized nine peptide fragments of NDP-MSH, deleting N- and C-terminal amino acids to determine the "minimally active" sequence of NDP-MSH. Additionally, five peptides were synthesized to study stereochemical inversion at the Phe 7 and Trp 9 positions in attempts to increase tetra- and tripeptide potencies. These peptide analogues were pharmacologically characterized at the mouse melanocortin MC1, MC3, MC4, and MC5 receptors. This study has identified the Ac-His-DPhe-Arg-Trp-NH(2) tetrapeptide as possessing 10 nM agonist activity at the brain MC4R. The tripeptide Ac-DPhe-Arg-Trp-NH(2) possessed micromolar agonist activities at the MC1R, MC4R, and MC5R but only slight stimulatory activity was observed at the MC3R (at up to 100 microM concentration). This study has also examined to importance of both N- and C-terminal NDP-MSH amino acids at the different melanocortin receptors, providing information for drug design and identification of putative ligand-receptor interactions.

EFEITO DE ÓLEOS ESSENCIAIS CÍTRICOS SOBRE Agrotis ipsilon (HUFNAGEL (LEPIDOPTERA:NOCTUIDAE

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Ingrid Schimidt Kaiser

2017-01-01

Full Text Available A utilização de plantas inseticidas é cada vez mais frequente no controle de pragas. As plantas podem produzir diferentes compostos com atividade inseticida. Os óleos essenciais destacam-se dentre estes compostos, possuindo diferentes modos de ação inseticida, podendo ser uma ferramenta útil no manejo integrado de pragas. O objetivo deste trabalho é avaliar o efeito de óleos essenciais cítricos e seu composto majoritário D-limonemo visando sua adoção como métodos alternativos de controle de Agrotis ipsilon (Hufnagel (Lepidoptera: Noctuidae. Para a realização do experimento foram utilizadas 50 lagartas de 1º ínstar por tratamento. Foram aplicados os óleos essenciais com auxilio do aerógrafo, sendo utilizado na concentração de 10% v v-1 para os óleos cítricos e o D-limoneno e para testemunha foi pulverizado água destilada. A avaliação foi realizada após 24, 48 e 72 horas verificando o número de lagartas mortas. Não foi observado efeito tóxico dos óleos essenciais cítricos e do D-limoneno sobre as lagartas de A. ipsilon. Deste modo, os óleos essenciais testados não são eficazes no controle da praga.

Modelo unibimodal simétrico-asimétrico con aplicación al estudio del RNA VIH-1

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Guillermo Martínez-Flórez

2014-06-01

Full Text Available Se definen dos nuevas distribuciones de probabilidad: modelo unibimodal simétrico con función de riesgo proporcional a la distribución normal y modelo unibimodal asimétrico con función de riesgo proporcional a la distribución normal asimétrica. Estos modelos permiten ajustar datos censurados con comportamiento bimodal y altos (o bajos niveles de curtosis comparado con la curtosis de la distribución normal y altos (o bajos niveles de asimetría. Además, se estiman los parámetros de los modelos por máxima verosimilitud y se determina la matriz de información observada. La flexibilidad de la nueva distribución se ilustra ajustando un conjunto de datos reales: el número de moléculas de ARN VIH-1 por mililitros de sangre medida en personas con pruebas confirmadas de presencia del VIH. Abstract. We define two new probability distributions, unibimodal symmetric model with proportional hazard function to the normal distribution and unibimodal asymmetric model with proportional hazard function to the skewnormal distribution. These models allow adjust censored data with bimodal behavior and high (or low levels of kurtosis compared with kurtosis of the normal distribution and high (or low levels of asymmetry. The model parameters are estimated by maximum likelihood and the observed information matrix is determined. The flexibility of the new distribution is illustrated by adjusting a set of real data, the number of molecules of HIV-1 RNA per milliliter of blood measured in individuals with confirmed test of the presence of HIV.

Histidine-lysine peptides as carriers of nucleic acids.

Science.gov (United States)

Leng, Qixin; Goldgeier, Lisa; Zhu, Jingsong; Cambell, Patricia; Ambulos, Nicholas; Mixson, A James

2007-03-01

With their biodegradability and diversity of permutations, peptides have significant potential as carriers of nucleic acids. This review will focus on the sequence and branching patterns of peptide carriers composed primarily of histidines and lysines. While lysines within peptides are important for binding to the negatively charged phosphates, histidines are critical for endosomal lysis enabling nucleic acids to reach the cytosol. Histidine-lysine (HK) polymers by either covalent or ionic bonds with liposomes augment transfection compared to liposome carriers alone. More recently, we have examined peptides as sole carriers of nucleic acids because of their intrinsic advantages compared to the bipartite HK/liposome carriers. With a protocol change and addition of a histidine-rich tail, HK peptides as sole carriers were more effective than liposomes alone in several cell lines. While four-branched polymers with a primary repeating sequence pattern of -HHK- were more effective as carriers of plasmids, eight-branched polymers with a sequence pattern of -HHHK- were more effective as carriers of siRNA. Compared to polyethylenimine, HK carriers of siRNA and plasmids had reduced toxicity. When injected intravenously, HK polymers in complex with plasmids encoding antiangiogenic proteins significantly decreased tumor growth. Furthermore, modification of HK polymers with polyethylene glycol and vascular-specific ligands increased specificity of the polyplex to the tumor by more than 40-fold. Together with further development and insight on the structure of HK polyplexes, HK peptides may prove to be useful as carriers of different forms of nucleic acids both in vitro and in vivo.

SM50 repeat-polypeptides self-assemble into discrete matrix subunits and promote appositional calcium carbonate crystal growth during sea urchin tooth biomineralization.

Science.gov (United States)

Mao, Yelin; Satchell, Paul G; Luan, Xianghong; Diekwisch, Thomas G H

2016-01-01

The two major proteins involved in vertebrate enamel formation and echinoderm sea urchin tooth biomineralization, amelogenin and SM50, are both characterized by elongated polyproline repeat domains in the center of the macromolecule. To determine the role of polyproline repeat polypeptides in basal deuterostome biomineralization, we have mapped the localization of SM50 as it relates to crystal growth, conducted self-assembly studies of SM50 repeat polypeptides, and examined their effect on calcium carbonate and apatite crystal growth. Electron micrographs of the growth zone of Strongylocentrotus purpuratus sea urchin teeth documented a series of successive events from intravesicular mineral nucleation to mineral deposition at the interface between tooth surface and odontoblast syncytium. Using immunohistochemistry, SM50 was detected within the cytoplasm of cells associated with the developing tooth mineral, at the mineral secreting front, and adjacent to initial mineral deposits, but not in muscles and ligaments. Polypeptides derived from the SM50 polyproline alternating hexa- and hepta-peptide repeat region (SM50P6P7) formed highly discrete, donut-shaped self-assembly patterns. In calcium carbonate crystal growth studies, SM50P6P7 repeat peptides triggered the growth of expansive networks of fused calcium carbonate crystals while in apatite growth studies, SM50P6P7 peptides facilitated the growth of needle-shaped and parallel arranged crystals resembling those found in developing vertebrate enamel. In comparison, SM50P6P7 surpassed the PXX24 polypeptide repeat region derived from the vertebrate enamel protein amelogenin in its ability to promote crystal nucleation and appositional crystal growth. Together, these studies establish the SM50P6P7 polyproline repeat region as a potent regulator in the protein-guided appositional crystal growth that occurs during continuous tooth mineralization and eruption. In addition, our studies highlight the role of species

CLASSIFICAÇÃO DE PACIENTES PEDIÁTRICOS EM UM HOSPITAL DE ENSINO DE TERESINA

Directory of Open Access Journals (Sweden)

Márcia Teles de Oliveira Gouveia

2010-01-01

Full Text Available La evaluación minuciosa del estado físico/emocional y el grado de dependencia de enfermería de los niños pueden respaldar una buena planificación de la asistencia, lo cual es posible por medio de sistemas de clasificación. El objetivo fue clasificar y evaluar pacientes pediátricos según el Instrumento de Clasificación de Pacientes Pediátricos (ICPP y su nivel de dependencia en relación al cuidado de enfermería. Es un estudio descriptivo y exploratorio, con enfoque cuantitativo, realizado en un hospital pediátrico universitario de la ciudad de Teresina-PI. La muestra se formó con 40 niños, se aplicó el ICPP y formulario específico. Se destacaron como resultados: predominio del sexo masculino (57,5%; lactante (30%; tiempo de hospitalización superior a 16 días; las causas más frecuentes de hospitalización fueron las afecciones hemolinfopoiéticas (23,81% y la mayoría fue clasificada como alta dependencia (72,5%. Es relevante el uso de sistemas de clasificación, que permite la identificación del perfil asistencial de los niños asistidos por la enfermería.

Poly-dipeptides encoded by the C9orf72 repeats bind nucleoli, impede RNA biogenesis, and kill cells.

Science.gov (United States)

Kwon, Ilmin; Xiang, Siheng; Kato, Masato; Wu, Leeju; Theodoropoulos, Pano; Wang, Tao; Kim, Jiwoong; Yun, Jonghyun; Xie, Yang; McKnight, Steven L

2014-09-05

Many RNA regulatory proteins controlling pre-messenger RNA splicing contain serine:arginine (SR) repeats. Here, we found that these SR domains bound hydrogel droplets composed of fibrous polymers of the low-complexity domain of heterogeneous ribonucleoprotein A2 (hnRNPA2). Hydrogel binding was reversed upon phosphorylation of the SR domain by CDC2-like kinases 1 and 2 (CLK1/2). Mutated variants of the SR domains changing serine to glycine (SR-to-GR variants) also bound to hnRNPA2 hydrogels but were not affected by CLK1/2. When expressed in mammalian cells, these variants bound nucleoli. The translation products of the sense and antisense transcripts of the expansion repeats associated with the C9orf72 gene altered in neurodegenerative disease encode GRn and PRn repeat polypeptides. Both peptides bound to hnRNPA2 hydrogels independent of CLK1/2 activity. When applied to cultured cells, both peptides entered cells, migrated to the nucleus, bound nucleoli, and poisoned RNA biogenesis, which caused cell death. Copyright © 2014, American Association for the Advancement of Science.

First delayed neutron emission measurements at ALTO with the neutron detector TETRA

International Nuclear Information System (INIS)

Testov, D.; Ancelin, S.; Bettane, J.; Ibrahim, F.; Kolos, K.; Mavilla, G.; Niikura, M.; Verney, D.; Wilson, J.; Kuznetsova, E.; Penionzhkevich, Yu.; Smirnov, V.; Sokol, E.

2013-01-01

Beta-decay properties are among the easiest and, therefore, the first ones to be measured to study new neutron-rich isotopes. Eventually, a very small number of nuclei could be sufficient to estimate their lifetime and neutron emission probability. With the new radioactive beam facilities which have been commissioned recently (or will be constructed shortly) new areas of neutron-rich isotopes will become reachable. To study beta-decay properties of such nuclei at IPN (Orsay) in the framework of collaboration with JINR (Dubna), a new experimental setup including the neutron detector of high efficiency TETRA was developed and commissioned

5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrapropynyloxy-2,8,14,20-tetrathiacalix[4]arene

Directory of Open Access Journals (Sweden)

Xiang-Gao Meng

2009-12-01

Full Text Available The title compound [systematic name: 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrapropynyloxy-2,8,14,20-tetrathiacalix[4]arene], C52H56O4S4, is an alkylated product bearing four propyne groups at the lower rim of a 5,11,17,23-tetra-tert-butyl-tetrathiacalix[4]arene. The molecule is located on a crystallographic twofold rotation axis, running through two S atoms and perpendicular to the long axis of the molecule. The four propyne groups, located in an alternate fashion above and below the mean plane of the four S atoms, are almost parallel to the calixarene long axis. The dihedral angle between the two crystallographically independent benzene rings is 86.77 (14°. Two tert-butyl groups are disordered over two positions with site occupancies of 0.59 (2 and 0.41 (2.

Biosíntesis y acumulación de carotenoides en frutos cítricos y su implicación en la calidad postcosecha

OpenAIRE

Lado Lindner, Joanna

2015-01-01

La conservación refrigerada es una de las tecnologías más utilizadas para preservar la calidad postcosecha de frutas y hortalizas. Los cítricos son el principal frutal que se produce en el mundo y el transporte refrigerado es esencial para conservar la calidad y cumplir con los requisitos de los mercados. Sin embargo, los cítricos presentan una alta sensibilidad a las bajas temperaturas. Los frutos de pomelos se encuentran entre los cítricos más sensibles al frío y desarrollan manchados en la...

A evolução do entendimento dos estudantes sobre o funcionamento do circuito elétrico simples em uma estrutura curricular recursiva

OpenAIRE

Coelho, Geide Rosa; Borges, Oto

2011-01-01

Relatamos um estudo sobre o entendimento dos estudantes sobre a física envolvida no funcionamento de um circuito elétrico simples. Detivemo-nos a investigar: (i)a mudança no entendimento dos estudantes sobre o funcionamento de circuito elétrico simples; (ii) o patamar de entendimento dos mesmos, sobre essa temática, ao final da terceira série. Desenvolvemos um instrumento qualitativo e criamos um sistema categórico hierarquizado constituído de quatro modelos sobre circuito elétrico simples. O...

Desenvolvimento de um monitor de apneia pediátrico

OpenAIRE

Caldeira, Gonçalo José Martins

2009-01-01

O trabalho apresentado tem por base o desenvolvimento de um monitor de apneia do sono pediátrico. Aborda questões ao nível da fisiologia respiratória e da mecânica pulmonar de um indivíduo. Apresenta uma proposta de desenvolvimento de um monitor de aquisição e identificação de sinais respiratórios, a fim de efectuar a detecção da apneia do sono.

Antibody reactivities to glutamate-rich peptides of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

DEFF Research Database (Denmark)

Jakobsen, P H; Theander, T G; Hviid, L

1996-01-01

Synthetic P. falciparum peptides were evaluated as tools in epidemiological investigations of malaria. Plasma IgM and IgG antibody reactivities against synthetic peptides covering sequences of glutamate-rich protein (GLURP) and acidic-basic repeat antigen (ABRA) were measured by ELISA...... in individuals from malaria-endemic areas of Sudan, Indonesia and The Gambia to study antibody responses to these peptides in donors living in areas of different malaria endemicity. IgG and IgM reactivities to the peptides increased with malaria endemicity, although there were no differences in reactivities...... tested were shortlived in most patients. In Gambian children with malaria, IgM reactivities but not IgG antibody reactivities against the ABRA peptide were higher in those with mild malaria than in those with severe malaria. The peptides may be useful in future epidemiological studies, especially...

Combinação de métodos paramétricos e não-paramétricos para estudo da estabilidade de cultivares de soja no Cerrado Tocantinense

Directory of Open Access Journals (Sweden)

Aristoteles Capone

2016-04-01

Full Text Available Objetivou-se com esse estudo avaliar a viabilidade da combinação de métodos paramétrico e não-paramétricos para inferir acerca da estabilidade de cultivares de soja no cerrado tocantinense. Para isso utilizou-se os dados de ensaios de competição conduzidos em quatro ambientes nas safras de 2009/10 e 2010/11 e na entressafra de 2010. Utilizou-se o delineamento em blocos casualizados com quatro repetições. As estimativas de estabilidade foram obtidas pelo método paramétrico sugerido por Livorenti e Matsuoka e pelos métodos não-paramétricos propostos por Huenh e Fox. Pelo método paramétrico, os cultivares M8766, M9056, P98Y70RR, M9144RR, JulianaRR e BRS8560RR acumularam o maior número de sinais positivos nos ambientes avaliados, sendo que os dois últimos apresentaram sinal negativo em um ambiente. Pela metodologia não-paramétrica foram discriminados como produtivos e estáveis apenas os quatro primeiros cultivares. Neste sentido, houve concordância na discriminação de cultivares produtivos e estáveis por ambos os métodos, desde que desconsiderados aqueles que apresentam sinal negativo entre os ambientes avaliados.  Assim, a combinação dessas metodologias além de apresentar simples aplicabilidade, mostra-se viável para inferir acerca da estabilidade e produtividade de cultivares de soja para o estado do Tocantins.Combination of parametric and nonparametric methods for stability study of soybean cultivars in the from Cerrado TocantinenseAbstract: The objective of this study was to evaluate the viability of combining parametric and nonparametric methods to infer about the stability of soybean cultivars in the cerrado from Tocantins state. Were used data from competition experiments conducted in four environments in crop 2009/10 and 2010/11 and between crop of 2010. A randomized block design were used with four replications. Estimates of stability were obtained by the parametric method suggested by Livorenti and Matsuoka

Development of simple sequence repeat markers and diversity analysis in alfalfa (Medicago sativa L.).

Science.gov (United States)

Wang, Zan; Yan, Hongwei; Fu, Xinnian; Li, Xuehui; Gao, Hongwen

2013-04-01

Efficient and robust molecular markers are essential for molecular breeding in plant. Compared to dominant and bi-allelic markers, multiple alleles of simple sequence repeat (SSR) markers are particularly informative and superior in genetic linkage map and QTL mapping in autotetraploid species like alfalfa. The objective of this study was to enrich SSR markers directly from alfalfa expressed sequence tags (ESTs). A total of 12,371 alfalfa ESTs were retrieved from the National Center for Biotechnology Information. Total 774 SSR-containing ESTs were identified from 716 ESTs. On average, one SSR was found per 7.7 kb of EST sequences. Tri-nucleotide repeats (48.8 %) was the most abundant motif type, followed by di-(26.1 %), tetra-(11.5 %), penta-(9.7 %), and hexanucleotide (3.9 %). One hundred EST-SSR primer pairs were successfully designed and 29 exhibited polymorphism among 28 alfalfa accessions. The allele number per marker ranged from two to 21 with an average of 6.8. The PIC values ranged from 0.195 to 0.896 with an average of 0.608, indicating a high level of polymorphism of the EST-SSR markers. Based on the 29 EST-SSR markers, assessment of genetic diversity was conducted and found that Medicago sativa ssp. sativa was clearly different from the other subspecies. The high transferability of those EST-SSR markers was also found for relative species.

Preliminary screening and identification of the hepatocarcinoma cell-binding peptide

International Nuclear Information System (INIS)

Zhu Xiaohua; Wu Hua

2004-01-01

Objective: To explore the feasibility of screening and isolating homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide library and to develop a new peptide which may be potentially used as targeting delivery carrier in the biological targeted diagnosis or therapy for liver cancer. Methods: A 12-mer peptide phage display library was used to screen and isolate peptides that bind to human hepatocarcinoma cells, and four rounds of subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones for human hepatocarcinoma cells were determined with enzyme-linked immunosorbent assay (ELISA) and compared with that to human liver cell and other tumor cells of different tissue origins, respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced through DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide, WH16, was determined with competitive inhibition test. Results: After four rounds of panning, the phages that were bound to and internalized in human hepatocarcinoma cells were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages for hepatocarcinoma cells. 56.67%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif . Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, that strongly support that cellular binding of the phage is mediated through its displayed peptide, and WH16 can also bind to HepG2. Conclusions: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide

Preliminary screening and identification of the hepatocarcinoma cell-binding peptide

Energy Technology Data Exchange (ETDEWEB)

Xiaohua, Zhu; Hua, Wu [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong Univ. of Science and Technology, Wuhan (China)

2004-12-15

Objective: To explore the feasibility of screening and isolating homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide library and to develop a new peptide which may be potentially used as targeting delivery carrier in the biological targeted diagnosis or therapy for liver cancer. Methods: A 12-mer peptide phage display library was used to screen and isolate peptides that bind to human hepatocarcinoma cells, and four rounds of subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones for human hepatocarcinoma cells were determined with enzyme-linked immunosorbent assay (ELISA) and compared with that to human liver cell and other tumor cells of different tissue origins, respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced through DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide, WH16, was determined with competitive inhibition test. Results: After four rounds of panning, the phages that were bound to and internalized in human hepatocarcinoma cells were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages for hepatocarcinoma cells. 56.67%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif . Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, that strongly support that cellular binding of the phage is mediated through its displayed peptide, and WH16 can also bind to HepG2. Conclusions: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide

A Tat-conjugated Peptide Nucleic Acid Tat-PNA-DR Inhibits Hepatitis B Virus Replication In Vitro and In Vivo by Targeting LTR Direct Repeats of HBV RNA

Science.gov (United States)

Zeng, Zhengyang; Han, Shisong; Hong, Wei; Lang, Yange; Li, Fangfang; Liu, Yongxiang; Li, Zeyong; Wu, Yingliang; Li, Wenxin; Zhang, Xianzheng; Cao, Zhijian

2016-01-01

Hepatitis B virus (HBV) infection is a major cause of chronic active hepatitis, cirrhosis, and primary hepatocellular carcinoma, all of which are severe threats to human health. However, current clinical therapies for HBV are limited by potential side effects, toxicity, and drug-resistance. In this study, a cell-penetrating peptide-conjugated peptide nucleic acid (PNA), Tat-PNA-DR, was designed to target the direct repeat (DR) sequences of HBV. Tat-PNA-DR effectively inhibited HBV replication in HepG2.2.15 cells. Its anti-HBV effect relied on the binding of Tat-PNA-DR to the DR, whereby it suppressed the translation of hepatitis B e antigen (HBeAg), HBsAg, HBV core, hepatitis B virus x protein, and HBV reverse transcriptase (RT) and the reverse transcription of the HBV genome. Furthermore, Tat-PNA-DR administered by intravenous injection efficiently cleared HBeAg and HBsAg in an acute hepatitis B mouse model. Importantly, it induced an 80% decline in HBV DNA in mouse serum, which was similar to the effect of the widely used clinical drug Lamivudine (3TC). Additionally, a long-term hydrodynamics HBV mouse model also demonstrated Tat-PNA-DR's antiviral effect. Interestingly, Tat-PNA-DR displayed low cytotoxicity, low mouse acute toxicity, low immunogenicity, and high serum stability. These data indicate that Tat-PNA-DR is a unique PNA and a promising drug candidate against HBV. PMID:26978579

A Tat-conjugated Peptide Nucleic Acid Tat-PNA-DR Inhibits Hepatitis B Virus Replication In Vitro and In Vivo by Targeting LTR Direct Repeats of HBV RNA

Directory of Open Access Journals (Sweden)

Zhengyang Zeng

2016-01-01

Full Text Available Hepatitis B virus (HBV infection is a major cause of chronic active hepatitis, cirrhosis, and primary hepatocellular carcinoma, all of which are severe threats to human health. However, current clinical therapies for HBV are limited by potential side effects, toxicity, and drug-resistance. In this study, a cell-penetrating peptide-conjugated peptide nucleic acid (PNA, Tat-PNA-DR, was designed to target the direct repeat (DR sequences of HBV. Tat-PNA-DR effectively inhibited HBV replication in HepG2.2.15 cells. Its anti-HBV effect relied on the binding of Tat-PNA-DR to the DR, whereby it suppressed the translation of hepatitis B e antigen (HBeAg, HBsAg, HBV core, hepatitis B virus x protein, and HBV reverse transcriptase (RT and the reverse transcription of the HBV genome. Furthermore, Tat-PNA-DR administered by intravenous injection efficiently cleared HBeAg and HBsAg in an acute hepatitis B mouse model. Importantly, it induced an 80% decline in HBV DNA in mouse serum, which was similar to the effect of the widely used clinical drug Lamivudine (3TC. Additionally, a long-term hydrodynamics HBV mouse model also demonstrated Tat-PNA-DR's antiviral effect. Interestingly, Tat-PNA-DR displayed low cytotoxicity, low mouse acute toxicity, low immunogenicity, and high serum stability. These data indicate that Tat-PNA-DR is a unique PNA and a promising drug candidate against HBV.

A 31-residue peptide induces aggregation of tau's microtubule-binding region in cells

Science.gov (United States)

Stöhr, Jan; Wu, Haifan; Nick, Mimi; Wu, Yibing; Bhate, Manasi; Condello, Carlo; Johnson, Noah; Rodgers, Jeffrey; Lemmin, Thomas; Acharya, Srabasti; Becker, Julia; Robinson, Kathleen; Kelly, Mark J. S.; Gai, Feng; Stubbs, Gerald; Prusiner, Stanley B.; Degrado, William F.

2017-09-01

The self-propagation of misfolded conformations of tau underlies neurodegenerative diseases, including Alzheimer's. There is considerable interest in discovering the minimal sequence and active conformational nucleus that defines this self-propagating event. The microtubule-binding region, spanning residues 244-372, reproduces much of the aggregation behaviour of tau in cells and animal models. Further dissection of the amyloid-forming region to a hexapeptide from the third microtubule-binding repeat resulted in a peptide that rapidly forms fibrils in vitro. We show that this peptide lacks the ability to seed aggregation of tau244-372 in cells. However, as the hexapeptide is gradually extended to 31 residues, the peptides aggregate more slowly and gain potent activity to induce aggregation of tau244-372 in cells. X-ray fibre diffraction, hydrogen-deuterium exchange and solid-state NMR studies map the beta-forming region to a 25-residue sequence. Thus, the nucleus for self-propagating aggregation of tau244-372 in cells is packaged in a remarkably small peptide.

PROCESS OPTIMIZATION OF TETRA ACETYL ETHYLENE DIAMINE ACTIVATED HYDROGEN PEROXIDE BLEACHING OF POPULUS NIGRA CTMP

OpenAIRE

Qiang Zhao; Junwen Pu; Shulei Mao; Guibo Qi

2010-01-01

To enhance the bleaching efficiency, the activator of tetra acetyl ethylene diamine (TAED) was used in conventional H2O2 bleaching. The H2O2/TAED bleaching system can accelerate the reaction rate and shorten bleaching time at relative low temperature, which can reduce the production cost. In this research, the process with hydrogen peroxide activated by TAED bleaching of Populus nigra chemi-thermo mechanical pulp was optimized. Suitable bleaching conditions were confirmed as follows: pulp con...

Iteração do plasma no circuito elétrico de descarga Theta – Pinch

OpenAIRE

Torres, Héctor; Barraza Sotomayor, Bernardo

1985-01-01

O sistema TUPÂ da UNICAMP (55 KJ, 1MA, 100 KV) é um circuito rápido de descarga que produz um pulso de corrente de 1MA, em um microssegundo. O campo magnético de 22 KG comprime e aquece o plasma a temperaturas muito grandes. Neste trabalho é estudado o comportamento dinâmico da iteração circuito elétrico – plasma. O modelo elétrico obtido é baseado em cálculos de energia magnético aplicado o principio dos trabalhos virtuais e sendo caracterizado o acoplamento do plasma através de parâmetros R...

CLE peptides regulate lateral root development in response to nitrogen nutritional status of plants.

Science.gov (United States)

Araya, Takao; von Wirén, Nicolaus; Takahashi, Hideki

2014-01-01

CLE (CLAVATA3/embryo surrounding region (ESR)) peptides control meristem functions in plants. Our recent study highlights the critical role of a peptide-receptor signaling module composed of nitrogen (N)-responsive CLE peptides and the CLAVATA1 (CLV1) leucine-rich repeat receptor-like kinase in controlling lateral root development in Arabidopsis thaliana. CLE1, -3, -4 and -7 are expressed in root pericycle cells in Arabidopsis roots under N-limited growth conditions. Overexpression of these CLE genes inhibits lateral root emergence from the primary root. The inhibitory action of N-responsive CLE peptides on lateral root development requires the function of CLV1 expressed in phloem companion cells in roots, suggesting that downstream signals are transferred through phloem for systemic regulation of root system architecture. An additional mechanism downstream of CLV1 feedback-regulates transcript levels of N-responsive CLE genes in roots for fine-tuning the signal amplitude.

Development of four-component synthesis of tetra- and pentasubstituted polyfunctional dihydropyrroles: free permutation and combination of aromatic and aliphatic amines.

Science.gov (United States)

Lv, Longyun; Zheng, Sichao; Cai, Xiaotie; Chen, Zhipeng; Zhu, Qiuhua; Liu, Shuwen

2013-04-08

We previously reported the novel efficient proton/heat-promoted four-component reactions (4CRs) of but-2-ynedioates, two same/different primary amines, and aldehydes for the synthesis of tetra- and pentasubstituted polyfunctional dihydropyrroles. If aromatic and aliphatic amines were used as reagents, four different series of products should be obtained via the permutation and combination of aromatic and aliphatic primary amines. However, only three/two rather four different series of tetra-/pentasubstisuted dihydropyrroles could be prepared via the proton/heat-promoted 4CRs. Herein, Cu(OAc)2·H2O, a Lewis acid being stable in air and water, was found to be an efficient catalyst for the 4CR synthesis of all the four different series of tetra-/pentasubstisuted dihydropyrroles. The copper-catalyzed 4CR could produce target products at room temperature in good to excellent yields. Interestingly, benzaldehyde, in addition to being used as a useful reactant for the synthesis of pentasubstituted dihydropyrroles, was found to be an excellent additive for preventing the oxidation of aromatic amines with copper(II) and ensuring the sooth conduct of the 4CRs for the synthesis of tetrasubstituted dihydropyrroles with aryl R(3). In addition, salicylic acid was found to be needed to increase the activities and yields of the copper-catalyzed 4CRs for the synthesis of petasubstituted diyhydropyrroles. On the basis of experimental results, the enamination/amidation/intramolecular cyclization mechanism was proposed and amidation is expected to be the rate-limited step in the copper-catalyzed 4CRs.

CONDUCTANCIA HIDRÁULICA EN PATRONES DE CÍTRICOS

OpenAIRE

RODRÍGUEZ GAMIR, JUAN

2012-01-01

La conductancia hidráulica determina la capacidad de transporte de agua afectando a las relaciones hídrias de la planta así como a la eficiencia de absorción de agua y nutrientes. Los patrones de cítricos difieren en su conductancia hidráulica debido a diferencias en la anatomía de los elementos vasculares o en la distribución del sistema radical pudiendo ser el principal factor que regula el desarrollo de los frutos y la respuesta de la planta a situaciones de estrés. Las relaciones hídricas...

Sodium tetra-hydro-borate as energy/hydrogen carrier, its history

International Nuclear Information System (INIS)

Demirci, U.B.; Miele, Ph.

2009-01-01

Sodium tetra-hydro-borate NaBH 4 is considered as being a promising energy/hydrogen carrier. NaBH 4 is not a new compound. It has been discovered in 1940's by Prof. H.C. Brown, Nobel Laureate in Chemistry in 1979. NaBH 4 has thus a history and this history distinguishes the NaBH 4 utilisation as hydrogen carrier from that as energy carrier. In fact, the history of NaBH 4 (for both utilizations) can be divided into three periods, each period being characterised by specific societal challenges. Whereas during the first period the challenges were military and political, the challenges in the third period (i.e. at present) are energetic, environmental, civilian, social and political. The second period was rather calm for NaBH 4 even if it was intensively used as a reducing agent in organic chemistry. (authors)

Adecuación de la calidad nutricional de los menús de un centro geriátrico

OpenAIRE

Aguado Cayo, Laura

2014-01-01

Introducción: Cada vez es mayor el número de personas que llegan a la vejez, por lo que el número de ancianos institucionalizados en centros geriátricos está en aumento y constituye uno de los grupos de población con mayor riesgo nutricional. En los pacientes geriátricos, una ingesta adecuada a los requerimientos podría, al menos, mejorar la evolución de muchas enfermedades y contribuir a una mejor calidad de vida.Objetivos: El objetivo principal de este estudio fue evaluar la adecuación y la...

Análisis comparativo de distintas toolkits para el reconocimiento biométrico de personas mediante voz

OpenAIRE

Ruíz, Silvia; Miranda, Ernesto; Herlein, Mauro; Etchart, Graciela; Alvez, Carlos E.

2017-01-01

El objetivo de este trabajo es realizar un análisis comparativo de distintas toolkits para el reconocimiento biométrico de personas mediante voz. Hoy en día los sistemas de identificación de personas se han convertido en una necesidad para la sociedad. A medida que avanza la tecnología y la aplicación de la misma en entornos tanto de ocio como de seguridad, la evolución en desarrollo biométrico es muy grande. Los sistemas de identificación o verificación tradicionales (tarjetas o claves) se h...

Development of a peptide substrate for detection of Sunn pest damage in wheat flour.

Science.gov (United States)

Hançerlioğulları, Begüm Zeynep; Köksel, Hamit; Dudak, Fahriye Ceyda

2018-05-07

Since the common protease substrates did not give satisfactory results for the determination of Sunn pest protease activity in damaged wheat, different peptide substrates derived from the repeat sequences of high molecular weight glutenin subunits were synthesized. Hydrolysis of peptides by pest protease was determined by HPLC. Among three peptides having the same consensus motifs, peptide1 (PGQGQQGYYPTSPQQ) showed the best catalytic efficiency. A novel assay was described for monitoring the enzymatic activity of protease extracted from damaged wheat flour. The selected peptide was labeled with a fluorophore (EDANS) and quencher (Dabcyl) to display fluorescence resonance energy transfer (FRET). The proteolytic activity was measured by the change in fluorescence intensity that occurred when the protease cleaved the peptide substrate. Furthermore, the developed assay was modified for rapid and easy detection of bug damage in flour. Flour samples were suspended in water and mixed with fluorescence peptide substrate. After centrifugation, the fluorescence intensities of the supernatants were determined which is proportional with the protease content of the flour. The total analysis time for the developed assay is estimated as 15 minutes. The developed assay permits a significant decrease in time and labor, offering sensitive detection of Sunn pest damage in wheat flour. This article is protected by copyright. All rights reserved.

Pentapeptide-repeat proteins that act as topoisomerase poison resistance factors have a common dimer interface

International Nuclear Information System (INIS)

Vetting, Matthew W.; Hegde, Subray S.; Zhang, Yong; Blanchard, John S.

2011-01-01

The pentapeptide repeat protein AlbG, provides self-resistance to the nonribosomally encoded hybrid polyketide-peptide termed albicidin. Analysis of the AlbG three-dimensional structure and the sequences of other pentapeptide repeat proteins that confer resistance to topiosomerase poisons suggests they have a similar dimer interface which may be critical to their interaction with topoisomerases. The protein AlbG is a self-resistance factor against albicidin, a nonribosomally encoded hybrid polyketide-peptide with antibiotic and phytotoxic properties produced by Xanthomonas albilineans. Primary-sequence analysis indicates that AlbG is a member of the pentapeptide-repeat family of proteins (PRP). The structure of AlbG from X. albilineans was determined at 2.0 Å resolution by SAD phasing using data collected from a single trimethyllead acetate derivative on a home source. AlbG folds into a right-handed quadrilateral β-helix composed of approximately eight semi-regular coils. The regularity of the β-helix is blemished by a large loop/deviation in the β-helix between coils 4 and 5. The C-terminus of the β-helix is capped by a dimerization module, yielding a dimer with a 110 Å semi-collinear β-helical axis. This method of dimer formation appears to be common to all PRP proteins that confer resistance to topoisomerase poisons and contrasts with most PRP proteins, which are typically monomeric

Preparation and testing of a tetra-amine copper(II) chitosan bead system for enhanced phosphate remediation.

Science.gov (United States)

Kumar, Ilango Aswin; Viswanathan, Natrayasamy

2018-03-01

A tetra-amine copper(II) chitosan bead system (TAC@CS composite beads) was developed by grafting tetra-amine copper(II) (TAC) with chitosan (CS) and utilized for phosphate removal. The prepared TAC@CS composite beads possess enhanced phosphate sorption capacity (SC) of 41.42 ± 0.071 mg/g than copper grafted chitosan (Cu@CS) composite, TAC and chitosan which were found to be 37.01 ± 0.803, 33.20 ± 0.650 and 7.24 ± 0.059 mg/g respectively. In batch mode, various adsorption influencing parameters like contact time, initial phosphate concentration, solution pH, co-anions and temperature were optimized for maximum phosphate sorption. The prepared adsorbents were characterized by FTIR, XRD, UV-Visible, SEM and EDAX analysis. The adsorption isotherms and thermodynamic parameters of the adsorbent were studied. The feasible phosphate uptake mechanism of TAC@CS biocomposite beads was reported. The reusability studies of TAC@CS composite beads were carried out using NaOH as elutant. The suitability of TAC@CS composite beads at field conditions was tested with phosphate contaminated field water samples collected from nearby areas of Dindigul district. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of bisphenol A-removing recombinant Escherichia coli by monomeric and dimeric surface display of bisphenol A-binding peptide.

Science.gov (United States)

Maruthamuthu, Murali Kannan; Hong, Jiyeon; Arulsamy, Kulandaisamy; Somasundaram, Sivachandiran; Hong, SoonHo; Choe, Woo-Seok; Yoo, Ik-Keun

2018-04-01

Peptide-displaying Escherichia coli cells were investigated for use in adsorptive removal of bisphenol A (BPA) both in Luria-Bertani medium including BPA or ATM thermal paper eluted wastewater. Two recombinant strains were constructed with monomeric and dimeric repeats of the 7-mer BPA-binding peptide (KSLENSY), respectively. Greater than threefold increased adsorption of BPA [230.4 µmol BPA per g dry cell weight (DCW)] was found in dimeric peptide-displaying cells compared to monomeric strains (63.4 µmol per g DCW) in 15 ppm BPA solution. The selective removal of BPA from a mixture of BPA analogs (bisphenol F and bisphenol S) was verified in both monomeric and dimeric peptide-displaying cells. The binding chemistry of BPA with the peptide was assumed, based on molecular docking analysis, to be the interaction of BPA with serine and asparagine residues within the 7-mer peptide sequence. The peptide-displaying cells also functioned efficiently in thermal paper eluted wastewater containing 14.5 ppm BPA.

Relación entre fragilidad y otros síndromes geriátricos en un grupo de ancianos institucionalizados

OpenAIRE

García Barajas, Ruth

2016-01-01

La fragilidad supone un estado previo a la discapacidad y se encuentra estrechamente relacionada con otros síndromes geriátricos de gran prevalencia en la población anciana. Pretendemos analizar la relación entre la fragilidad y otros síndromes geriátricos en un grupo de ancianos institucionalizados. Para ello se ha realizado un estudio observacional transversal en una muestra de 46 ancianos (18 varones y 28 mujeres) institucionalizados. Las mediciones antropométricas se realizaron sigu...

A novel peptide from the ACEI/BPP-CNP precursor in the venom of Crotalus durissus collilineatus.

Science.gov (United States)

Higuchi, Shigesada; Murayama, Nobuhiro; Saguchi, Ken-ichi; Ohi, Hiroaki; Fujita, Yoshiaki; da Silva, Nelson Jorge; de Siqueira, Rodrigo José Bezerra; Lahlou, Saad; Aird, Steven D

2006-10-01

In crotaline venoms, angiotensin-converting enzyme inhibitors [ACEIs, also known as bradykinin potentiating peptides (BPPs)], are products of a gene coding for an ACEI/BPP-C-type natriuretic peptide (CNP) precursor. In the genes from Bothrops jararaca and Gloydius blomhoffii, ACEI/BPP sequences are repeated. Sequencing of a cDNA clone from venom glands of Crotalus durissus collilineatus showed that two ACEIs/BPPs are located together at the N-terminus, but without repeats. An additional sequence for CNP was unexpectedly found at the C-terminus. Homologous genes for the ACEI/BPP-CNP precursor suggest that most crotaline venoms contain both ACEIs/BPPs and CNP. The sequence of ACEIs/BPPs is separated from the CNP sequence by a long spacer sequence. Previously, there was no evidence that this spacer actually coded any expressed peptides. Aird and Kaiser (1986, unpublished) previously isolated and sequenced a peptide of 11 residues (TPPAGPDVGPR) from Crotalus viridis viridis venom. In the present study, analysis of the cDNA clone from C. d. collilineatus revealed a nearly identical sequence in the ACEI/BPP-CNP spacer. Fractionation of the crude venom by reverse phase HPLC (C(18)), and analysis of the fractions by mass spectrometry (MS) indicated a component of 1020.5 Da. Amino acid sequencing by MS/MS confirmed that C. d. collilineatus venom contains the peptide TPPAGPDGGPR. Its high proline content and paired proline residues are typical of venom hypotensive peptides, although it lacks the usual N-terminal pyroglutamate. It has no demonstrable hypotensive activity when injected intravenously in rats; however, its occurrence in the venoms of dissimilar species suggests that its presence is not accidental. Evidence suggests that these novel toxins probably activate anaphylatoxin C3a receptors.

ST proteins, a new family of plant tandem repeat proteins with a DUF2775 domain mainly found in Fabaceae and Asteraceae.

Science.gov (United States)

Albornos, Lucía; Martín, Ignacio; Iglesias, Rebeca; Jiménez, Teresa; Labrador, Emilia; Dopico, Berta

2012-11-07

Many proteins with tandem repeats in their sequence have been described and classified according to the length of the repeats: I) Repeats of short oligopeptides (from 2 to 20 amino acids), including structural cell wall proteins and arabinogalactan proteins. II) Repeats that range in length from 20 to 40 residues, including proteins with a well-established three-dimensional structure often involved in mediating protein-protein interactions. (III) Longer repeats in the order of 100 amino acids that constitute structurally and functionally independent units. Here we analyse ShooT specific (ST) proteins, a family of proteins with tandem repeats of unknown function that were first found in Leguminosae, and their possible similarities to other proteins with tandem repeats. ST protein sequences were only found in dicotyledonous plants, limited to several plant families, mainly the Fabaceae and the Asteraceae. ST mRNAs accumulate mainly in the roots and under biotic interactions. Most ST proteins have one or several Domain(s) of Unknown Function 2775 (DUF2775). All deduced ST proteins have a signal peptide, indicating that these proteins enter the secretory pathway, and the mature proteins have tandem repeat oligopeptides that share a hexapeptide (E/D)FEPRP followed by 4 partially conserved amino acids, which could determine a putative N-glycosylation signal, and a fully conserved tyrosine. In a phylogenetic tree, the sequences clade according to taxonomic group. A possible involvement in symbiosis and abiotic stress as well as in plant cell elongation is suggested, although different STs could play different roles in plant development. We describe a new family of proteins called ST whose presence is limited to the plant kingdom, specifically to a few families of dicotyledonous plants. They present 20 to 40 amino acid tandem repeat sequences with different characteristics (signal peptide, DUF2775 domain, conservative repeat regions) from the described group of 20 to 40

Diversidade genética de porta-enxertos cítricos baseada em marcadores moleculares RAPD

Directory of Open Access Journals (Sweden)

Schäfer Gilmar

2004-01-01

Full Text Available Este trabalho teve como objetivo caracterizar a diversidade genética, através do marcador molecular RAPD, dos porta-enxertos da Coleção de Citros da Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul (EEA/UFRGS e acessos de porta-enxertos cítricos coletados em viveiristas da Região do Vale do Rio Caí do estado do Rio Grande do Sul. Para tanto, coletaram-se folhas de nove porta-enxertos cítricos da EEA/UFRGS e de dez acessos de trifoliata (Poncirus trifoliata de viveiristas. Com o uso de nove seqüências inicializadoras, foi possível separar os porta-enxertos cítricos em dois grupos principais, um formado pelo limoeiro ?Cravo? e outro pelo trifoliata e seus híbridos, apresentando alta dissimilaridade genética entre os grupos. Marcadores moleculares RAPD foram eficientes para caracterizar variedades de porta-enxertos de citros e para separar o porta-enxerto P. trifoliata de seus híbridos podendo serem utilizados para caracterização de plantas matrizes, análise de variabilidade genética entre genitores em programas de melhoramento genético de porta-enxertos e para identificar a origem sexual ou nucelar de mudas de trifoliata em viveiros comerciais.

Peptides and Anti-peptide Antibodies for Small and Medium Scale Peptide and Anti-peptide Affinity Microarrays: Antigenic Peptide Selection, Immobilization, and Processing.

Science.gov (United States)

Zhang, Fan; Briones, Andrea; Soloviev, Mikhail

2016-01-01

This chapter describes the principles of selection of antigenic peptides for the development of anti-peptide antibodies for use in microarray-based multiplex affinity assays and also with mass-spectrometry detection. The methods described here are mostly applicable to small to medium scale arrays. Although the same principles of peptide selection would be suitable for larger scale arrays (with 100+ features) the actual informatics software and printing methods may well be different. Because of the sheer number of proteins/peptides to be processed and analyzed dedicated software capable of processing all the proteins and an enterprise level array robotics may be necessary for larger scale efforts. This report aims to provide practical advice to those who develop or use arrays with up to ~100 different peptide or protein features.

Therapeutic peptides for cancer therapy. Part II - cell cycle inhibitory peptides and apoptosis-inducing peptides.

Science.gov (United States)

Raucher, Drazen; Moktan, Shama; Massodi, Iqbal; Bidwell, Gene L

2009-10-01

Therapeutic peptides have great potential as anticancer agents owing to their ease of rational design and target specificity. However, their utility in vivo is limited by low stability and poor tumor penetration. The authors review the development of peptide inhibitors with potential for cancer therapy. Peptides that arrest the cell cycle by mimicking CDK inhibitors or induce apoptosis directly are discussed. The authors searched Medline for articles concerning the development of therapeutic peptides and their delivery. Inhibition of cancer cell proliferation directly using peptides that arrest the cell cycle or induce apoptosis is a promising strategy. Peptides can be designed that interact very specifically with cyclins and/or cyclin-dependent kinases and with members of apoptotic cascades. Use of these peptides is not limited by their design, as a rational approach to peptide design is much less challenging than the design of small molecule inhibitors of specific protein-protein interactions. However, the limitations of peptide therapy lie in the poor pharmacokinetic properties of these large, often charged molecules. Therefore, overcoming the drug delivery hurdles could open the door for effective peptide therapy, thus making an entirely new class of molecules useful as anticancer drugs.

Narrativas gráficas em contextos pediátricos

OpenAIRE

Garcia, Ricardo Miguel Simões

2012-01-01

Dissertação de mestrado em Sociologia da Infância Resumo: este texto resulta de investigação sociológica conduzida em espaços pediátricos, visando perceber como as crianças estruturam representações sociais relativas ao universo hospitalar, através da recolha de desenhos feitos por crianças hospitalizadas em diversos contextos geográficos. O trabalho é fundamentado numa incursão pelos campos teóricos da Sociologia da Infância, Representações Sociais e Cultura Visual. Dos dados ...

Preliminary screening and identification of the peptide binding to hepatocarcinoma cell

International Nuclear Information System (INIS)

Zhu Xiaohua; Wu Ha

2004-01-01

Objective: The present study was performed to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide library with the purpose of developing a new peptide which may be potentially used as target delivery carrier in the biological target diagnosis or therapy for liver cancer. Methods: A peptide 12-mer phage display library was used to screen and isolate peptide that bind to human hepatocarcinoma cell, and four rounds subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones to human hepatocarcinoma cell were determined with ELISA and compared with human liver cell and other tumor cells of different tissue origins respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced though DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide WH16 was determined with competitive inhibition test. Results: After four rounds panning, the phages that bound to and internalized in human hepatocarcinoma cell were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages to hepatpcarcinoma cells 56.57%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif. Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, which strongly support that cellular binding of phage is mediated though its displayed peptide and WH16 can also bind to HepG2. Conclusion: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide libraries. The sequence of peptide that can bind to

Preliminary screening and identification of the peptide binding to hepatocarcinoma cell

Energy Technology Data Exchange (ETDEWEB)

Xiaohua, Zhu; Ha, Wu [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)

2004-07-01

Objective: The present study was performed to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide library with the purpose of developing a new peptide which may be potentially used as target delivery carrier in the biological target diagnosis or therapy for liver cancer. Methods: A peptide 12-mer phage display library was used to screen and isolate peptide that bind to human hepatocarcinoma cell, and four rounds subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones to human hepatocarcinoma cell were determined with ELISA and compared with human liver cell and other tumor cells of different tissue origins respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced though DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide WH16 was determined with competitive inhibition test. Results: After four rounds panning, the phages that bound to and internalized in human hepatocarcinoma cell were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages to hepatpcarcinoma cells 56.57%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif. Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, which strongly support that cellular binding of phage is mediated though its displayed peptide and WH16 can also bind to HepG2. Conclusion: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide libraries. The sequence of peptide that can bind to

Uso do óxido nítrico em pediatria Inhaled nitric oxide in pediatrics

Directory of Open Access Journals (Sweden)

José R. Fioretto

2003-11-01

Full Text Available OBJETIVO: Rever a literatura sobre óxido nítrico inalatório e descrever suas principais indicações clínicas em pediatria. FONTES DOS DADOS: Revisão bibliográfica e seleção de publicações mais relevantes sobre óxido nítrico inalatório, utilizando a base de dados Medline (últimos dez anos e a base de dados Cochrane de revisões sistemáticas. SÍNTESE DOS DADOS: A revisão incluiu os seguintes tópicos: introdução; metabolismo e efeitos biológicos; aplicações clínicas; dose, administração e retirada do gás; precações e efeitos adversos e contra-indicações. Quanto às aplicações clínicas, foram descritos o uso de óxido nítrico em hipertensão pulmonar persistente e insuficiência respiratória de recém-nascidos, síndrome do desconforto respiratório agudo, hipertensão pulmonar primária, cirurgia cardíaca, doença pulmonar obstrutiva crônica, anemia falciforme e broncoespasmo. CONCLUSÕES: O óxido nítrico inalatório é um tratamento com amplas possibilidades de utilização em clínica pediátrica. Seu uso é seguro em ambiente de terapia intensiva sob monitorização rigorosa. Como vasodilatador pulmonar seletivo, o óxido nítrico tem efeitos benéficos sobre as trocas gasosas e ventilação. Estudos controlados que enfoquem a administração precoce do gás são necessários em muitas condições, principalmente na síndrome do desconforto respiratório agudo.OBJECTIVE: To review the literature on inhaled nitric oxide and to describe its main clinical applications in pediatrics. SOURCES OF DATA: A 10 year literature review with selection of the most important publications on inhaled nitric oxide, using the Medline and Cochrane Systematic Review databases. SUMMARY OF THE FINDINGS: This review was organized as follows: introduction; metabolism and biological effects; clinical applications; dosage, gas administration and weaning; precautions and side-effects. Inhaled nitric oxide use was described in

El papel de óxido nítrico en la hemodinámica, hemostasia e inflamación

Directory of Open Access Journals (Sweden)

Andrés Pérez Ruiz

1997-12-01

Full Text Available El óxido nítrico debe ser considerado el nitrovasodilatador endógeno, acción que mimetizan los compuestos utilizados por la clínica por más de 100 años. En el tejido vascular existe una utilización continua de L-arginina que aumenta la producción de ácido nítrico, al mismo tiempo que tiene un papel fundamental en la regulación de la presión arterial. Se ha demostrado que el óxido nítrico inhibe la agregación plaquetaria, así como que se opone a la adhesión de plaquetas a fibras de colágeno y a otras proteínas adhesivas, asimismo, el óxido nítrico producido por macrófagos actúa como un radical libre y es citotóxico para ciertos microorganismos y células tumorales.The nitric oxide should be considered as the endogenous nitrovasodilator, an action that is mimicked by the compounds used by the clinics for more than 100 years. In the vascular tissue there is a continual utilization of L-arginine that increases the production of nitric acid and that plays an important role in the regulation of blood pressure. It has been shown that the nitric acid inhibits the platelet aggregation and opposes itself to the adhesion of platelets to collagen and other adhesive proteins. The nitric oxide produced by macrophages acts as a free radical and it is cytotoxic for certain microorganisms and tumoral cells.

Peptides, polypeptides and peptide-polymer hybrids as nucleic acid carriers.

Science.gov (United States)

Ahmed, Marya

2017-10-24

Cell penetrating peptides (CPPs), and protein transduction domains (PTDs) of viruses and other natural proteins serve as a template for the development of efficient peptide based gene delivery vectors. PTDs are sequences of acidic or basic amphipathic amino acids, with superior membrane trespassing efficacies. Gene delivery vectors derived from these natural, cationic and cationic amphipathic peptides, however, offer little flexibility in tailoring the physicochemical properties of single chain peptide based systems. Owing to significant advances in the field of peptide chemistry, synthetic mimics of natural peptides are often prepared and have been evaluated for their gene expression, as a function of amino acid functionalities, architecture and net cationic content of peptide chains. Moreover, chimeric single polypeptide chains are prepared by a combination of multiple small natural or synthetic peptides, which imparts distinct physiological properties to peptide based gene delivery therapeutics. In order to obtain multivalency and improve the gene delivery efficacies of low molecular weight cationic peptides, bioactive peptides are often incorporated into a polymeric architecture to obtain novel 'polymer-peptide hybrids' with improved gene delivery efficacies. Peptide modified polymers prepared by physical or chemical modifications exhibit enhanced endosomal escape, stimuli responsive degradation and targeting efficacies, as a function of physicochemical and biological activities of peptides attached onto a polymeric scaffold. The focus of this review is to provide comprehensive and step-wise progress in major natural and synthetic peptides, chimeric polypeptides, and peptide-polymer hybrids for nucleic acid delivery applications.

Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

DEFF Research Database (Denmark)

Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2008-01-01

An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...... application. Also demonstrated is the effect of non-zero UFTPS output impedance on envelope tracking performance. At 13W average (156W peak) RF output, a reduction of DC input power consumption from 93W (14% efficiency) to 54W (24% efficiency) is obtained by moving from a fixed RF power amplifier supply...

ASSOCIAÇÃO ENTRE O EQUILÍBRIO POSTURAL E INDICADORES ANTROPOMÉTRICOS EM ESCOLARES

Directory of Open Access Journals (Sweden)

Simone Lara

2017-11-01

Full Text Available RESUMO Objetivo: Analisar a associação entre o equilíbrio postural e indicadores antropométricos em escolares do primeiro ano do ensino fundamental. Métodos: Estudo transversal, descritivo e quantitativo que incluiu crianças regularmente matriculadas no primeiro ano do ensino fundamental, de ambos os sexos, na faixa etária de 6 a 7 anos. Foram excluídas as crianças com qualquer incapacidade física ou cognitiva, as que não participaram de todas as etapas de avaliação do estudo ou as que não conseguiram realizar a avaliação do equilíbrio postural. As crianças realizaram uma avaliação do equilíbrio por meio da posturografia dinâmica computadorizada (PDC, por meio dos testes de organização sensorial (TOSs em seis diferentes condições sensoriais. Para verificar os indicadores antropométricos, foram avaliadas as medidas de peso corporal e estatura, para posterior cálculo do índice de massa corporal (IMC, sendo este categorizado em quatro grupos: baixo peso, normal, sobrepeso e obesidade. Resultados: Foram incluídas 80 crianças (6,2±0,8 anos, sendo 47 meninas (58,8%. A análise dos indicadores antropométricos identificou 26,3% de escolares com sobrepeso e 15% com obesidade. As crianças apresentaram médias abaixo dos valores de referência considerados para sua faixa etária nas condições III e VI. Foi verificada associação negativa entre a condição V com o IMC e uma associação positiva entre os valores abaixo da normalidade na condição VI com o sobrepeso e a obesidade. Conclusões: Foram verificadas associações entre o excesso de peso corporal e valores abaixo da normalidade em algumas condições do equilíbrio, indicando que os indicadores antropométricos interferiram no equilíbrio postural das crianças.

Indicadores antropométricos como preditores de pressão arterial elevada em adolescentes

Directory of Open Access Journals (Sweden)

Carmem Cristina Beck

2011-02-01

Full Text Available FUNDAMENTO: A hipertensão arterial está relacionada ao incremento da gordura corporal, a qual pode ser avaliada por meio de indicadores antropométricos. OBJETIVO: Determinar o poder preditivo de indicadores antropométricos e estabelecer seus pontos de corte como discriminadores de pressão arterial elevada. MÉTODOS: Estudo transversal realizado com uma amostra de 660 adolescentes de 14 a 19 anos sendo 51,9% moças. Foram considerados os seguintes indicadores antropométricos: índice de massa corporal (IMC, circunferência da cintura, razão cintura/estatura e índice de conicidade. A pressão arterial elevada foi caracterizada por valores acima do percentil 90 para pressão arterial sistólica e/ou pressão arterial diastólica. Para identificação dos preditores de pressão arterial elevada, foi adotada a análise das curvas Receiver Operating Characteristic (ROC, com intervalo de confiança de 95%. Posteriormente, identificaram-se os pontos de corte com suas respectivas sensibilidades e especificidades. RESULTADOS: As áreas sob as curvas ROC com os intervalos de confiança foram: rapazes - circunferência de cintura = 0,80 (0,72-0,89; IMC = 0,79 (0,68-0,89; razão cintura/estatura = 0,77 (0,66-0,88; índice de conicidade = 0,69 (0,56-0,81 e para as moças - circunferência de cintura = 0,96 (0,92-1,00; IMC = 0,95 (0,87-1,00; razão cintura/estatura = 0,93 (0,85-1,00; índice de conicidade = 0,74 (0,50-0,98. Os diversos pontos de corte dos indicadores antropométricos com melhores poderes preditivos e suas respectivas sensibilidades e especificidades foram identificados. CONCLUSÃO: Apesar de a razão cintura/estatura e de o IMC terem apresentado boas áreas sob a curva ROC, sugere-se a utilização da circunferência de cintura para a predição da pressão arterial elevada.

Temporal trend studies on tetra- and pentabrominated diphenyl ethers and hexabromocyclododecane in guillemot egg from the Baltic Sea.

Science.gov (United States)

Sellström, Ulla; Bignert, Anders; Kierkegaard, Amelie; Häggberg, Lisbeth; de Wit, Cynthia A; Olsson, Mats; Jansson, Bo

2003-12-15

Guillemot eggs from the Baltic Sea, sampled between 1969 and 2001, were analyzed for tetra- and pentabromodiphenyl ethers (2,2',4,4'-tetraBDE (BDE-47), 2,2',4,4',5-pentaBDE (BDE-99), and 2,2',4,4',6-pentaBDE (BDE-100)), and hexabromocyclododecane (HBCD). This temporal trend study indicates that the concentrations of the polybrominated diphenyl ether compounds increased from the 1970s to the 1980s, peaking around the mid- to the late-1980s. These peaks are then followed by a rapid decrease in concentrations during the rest of the study period, with the concentrations of the major BDE congener below 100 ng/g lipid weight at the end of the period. This corresponds to less than 10% of its peak values. The concentrations of HBCD show a different pattern over time. After a peak in the middle of the 1970s followed by a decrease, the concentrations increased during the latter part of the 1980s. During the recent 10-yr period no significant change has occurred, and the annual mean concentrations are more or less stable at a higher level as compared to the beginning of the study period.

Exercício físico, indicadores antropométricos, risco coronariano e qualidade de vida de policiais militares

OpenAIRE

Silva, Franciele Cascaes da

2014-01-01

Esta pesquisa teve como objetivos: 1) revisar sistematicamente através de estudos observacionais produções científicas sobre indicadores antropométricos de obesidade e qualidade de vida de policiais; 2) verificar as associações das características ocupacionais, antropométricas, de atividade física no lazer com o risco coronariano e qualidade de vida; e 3) comparar os efeitos da natação e caminhada sobre indicadores antropométricos de obesidade, nível de atividade física, risco coronariano e q...

Microstructure and nanomechanical properties of enamel remineralized with asparagine–serine–serine peptide

International Nuclear Information System (INIS)

Chung, Hsiu-Ying; Li, Cheng Che

2013-01-01

A highly biocompatible peptide, triplet repeats of asparagine–serine–serine (3NSS) was designed to regulate mineral deposition from aqueous ions in saliva for the reconstruction of enamel lesions. Healthy human enamel was sectioned and acid demineralized to create lesions, then exposed to the 3NSS peptide solution, and finally immersed in artificial saliva for 24 h. The surface morphology and roughness were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. X-ray diffraction (XRD) was used to identify the phases and crystallinity of the deposited minerals observed on the enamel surface. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to quantitatively analyze the mineral variation by calculating the relative integrated-area of characteristic bands. Nanohardness and elastic modulus measured by nanoindentation at various treatment stages were utilized to evaluate the degree of recovery. Biomimetic effects were accessed according to the degree of nanohardness recovery and the amount of hydroxyapatite deposition. The charged segments in the 3NSS peptide greatly attracted aqueous ions from artificial saliva to form hydroxyapatite crystals to fill enamel caries, in particular the interrod areas, resulting in a slight reduction in overall surface roughness. Additionally, the deposited hydroxyapatites were of a small crystalline size in the presence of the 3NSS peptide, which effectively restrained the plastic deformations and thus resulted in greater improvements in nanohardness and elastic modulus. The degree of nanohardness recovery was 5 times greater for remineralized enamel samples treated with the 3NSS peptide compared to samples without peptide treatment. - Highlights: ► The degree of nanohardness recovery of enamel was 4 times greater with the aid of 3NSS peptide. ► 3NSS peptide promoted the formation of hydroxyapatites with a smaller crystalline size (14 nm). ► 3NSS

Niveles de actividad física asociados a factores sociodemograficos, antropométricos y conductuales en universitarios de Cartagena (Colombia)

OpenAIRE

Shyrley Díaz Cárdenas; Farith González Martínez; Katherine Arrieta Vergara

2014-01-01

Objetivo: Describir el nivel de actividad física y su asociación con factores sociodemográficos, antropométricos y conductuales en universitarios de Cartagena (Colombia). Materiales y métodos: Estudio de corte transversal en 670 universitarios seleccionados por muestreo probabilístico. Se diseñó y aplicó una encuesta estructurada para evaluar el nivel de actividad física (International Physical Activity Questionnaire (IPAQ) y los factores asociados (aspectos sociodemográficos, antropométricos...

Tunable properties of novel tetra-functional fluorene-based benzoxazines from mixed amines: Synthesis, characterization and curing kinetics

International Nuclear Information System (INIS)

Feng, Tiantian; Wang, Jun; Pan, Lan; Derradji, Mehdi; Ramdani, Noureddine; Liu, Wenbin; Zhou, Haoran

2016-01-01

Highlights: • Synthesis of tetra-functional fluorene-based benzoxazines with tunable properties. • Cure reaction could be successfully described with the autocatalytic model. • The benzoxazines show an excellent heat resistance with T_g of 291–307 °C. • The benzoxazines exhibit good thermal stability with T_5 over 340 °C. - Abstract: A series of tetra-functional fluorene-based benzoxazines containing both flexible linear aliphatic chain and rigid aromatic structure in their backbones were synthesized using mixed amines such as aniline and n-octylamine, 2,7-dihydroxy-9,9-bis-(4-hydroxyphenyl)fluorene (THPF) and paraformaldehyde as raw materials via Mannich reaction. The prepared benzoxazine monomers were identified by fourier transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance ("1H NMR). In addition, the curing behavior, curing kinetics and rheological properties of these monomers as well as the thermal and mechanical properties of their cured resins were studied using a rheometer, differential scanning calorimeter (DSC), thermogravimetric analyzer (TGA), and dynamic thermomechanical analyzer (DMA). The newly developed benzoxazines show good processibility, excellent thermal stability and high glass transition temperature (T_g) values ranging from 291 to 307 °C. By varying the proportion of n-octylamine to aniline, the properties of these resins are tuned.

The Plant Leucine-Rich Repeat Receptor-Like Kinase PSY1R from Head to Toe

DEFF Research Database (Denmark)

Oehlenschlæger, Christian Berg

PSY1R belongs to the family of plant leucine-rich repeat receptor-like kinases that play important roles in processes such as growth regulation and plant immunity response. PSY1R was proposed to be the receptor of the plant peptide hormone PSY1 which promotes cell expansion. PSY1R was furthermore...... is activated. This work provides the first study of the direct interaction between PSY1R and the peptide ligand PSY1. The binding was evaluated both for full length PSY1R expressed in plants and for the isolated extracellular domain expressed in insect cells. PSY1 binds to the extracellular domain of PSY1R...... shown to phosphorylate and regulate the activity of the plasma membrane localized H+-ATPase, AHA2. While the mechanism of PSY1R-mediated AHA2 phosphorylation has previously been studied in detail, little is known about how PSY1R binds PSY1 peptide ligand and how the intracellular PSY1R kinase domain...

Análisis métrico de las comunicaciones de la revista Centro Azúcar

Directory of Open Access Journals (Sweden)

Luis Ernesto Paz Enrique

2016-03-01

Full Text Available Las publicaciones científicas en línea generalmente se apoyan en los análisis métricos, favoreciendo la descripción de las revistas para su mejora continua. La revista Centro Azúcar se encuentra hace varios años en evaluación por bases de datos de prestigio internacional. La publicación carece de un estudio métrico que refleje la calidad de la publicación en consonancia a los indicadores establecidos por las fuentes de indización. Se plantean como objetivos del estudio examinar la producción científica de la revista Centro Azúcar desde el 2011 hasta el 2015, examinar las referencias contenidas en el período mencionado e identificar los índices de endogamia editorial presentes en la productividad y las referencias de los artículos publicados por la revista. Para la obtención de resultados se emplean métodos en los niveles teórico y empírico, destacándose el método bibliométrico. Se identifican varios aspectos que atentan contra la calidad de la publicación. Se aborda de forma novedosa el comportamiento de la endogamia editorial en las referencias. Se emiten valoraciones y se establecen aspectos a considerar por la publicación para que sea indizada en bases de datos de prestigio internacional.

Cathepsin-Mediated Cleavage of Peptides from Peptide Amphiphiles Leads to Enhanced Intracellular Peptide Accumulation

Energy Technology Data Exchange (ETDEWEB)

Acar, Handan [Institute; Department; Samaeekia, Ravand [Institute; Department; Schnorenberg, Mathew R. [Institute; Department; Medical; Sasmal, Dibyendu K. [Institute; Huang, Jun [Institute; Tirrell, Matthew V. [Institute; Institute; LaBelle, James L. [Department

2017-08-24

Peptides synthesized in the likeness of their native interaction domain(s) are natural choices to target protein protein interactions (PPIs) due to their fidelity of orthostatic contact points between binding partners. Despite therapeutic promise, intracellular delivery of biofunctional peptides at concentrations necessary for efficacy remains a formidable challenge. Peptide amphiphiles (PAs) provide a facile method of intracellular delivery and stabilization of bioactive peptides. PAs consisting of biofunctional peptide headgroups linked to hydrophobic alkyl lipid-like tails prevent peptide hydrolysis and proteolysis in circulation, and PA monomers are internalized via endocytosis. However, endocytotic sequestration and steric hindrance from the lipid tail are two major mechanisms that limit PA efficacy to target intracellular PPIs. To address these problems, we have constructed a PA platform consisting of cathepsin-B cleavable PAs in which a selective p53-based inhibitory peptide is cleaved from its lipid tail within endosomes, allowing for intracellular peptide accumulation and extracellular recycling of the lipid moiety. We monitor for cleavage and follow individual PA components in real time using a resonance energy transfer (FRET)-based tracking system. Using this platform, components in real time using a Forster we provide a better understanding and quantification of cellular internalization, trafficking, and endosomal cleavage of PAs and of the ultimate fates of each component.

Peptide modified ZnO nanoparticles as gas sensors array for volatile organic compounds (VOCs)

Science.gov (United States)

Mascini, Marcello; Gaggiotti, Sara; Della Pelle, Flavio; Di Natale, Corrado; Qakala, Sinazo; Iwuoha, Emmanuel; Pittia, Paola; Compagnone, Dario

2018-04-01

In this work a peptide based gas sensor array based of ZnO nanoparticles (ZnONPs) has been realized. Four different pentapeptides molecularly modelled for alcohols and esters having cysteine as a common spacer have been immobilized onto ZnONPs. ZnONPs have been morphologically and spectroscopically characterized. Modified nanoparticles have been then deposited onto quartz crystal microbalances (QCMs) and used as gas sensors with nitrogen as carrier gas. Analysis of the pure compounds modelled demonstrated a nice fitting of modelling with real data. The peptide based ZnONPs had very low sensitivity to water, compared to previously studied AuNPs peptide based gas sensors allowing the use of the array on samples with high water content. Real samples of fruit juices have been assayed; stability of the signal, good repeatability and discrimination ability of the array was achieved.

Peptide Modified ZnO Nanoparticles as Gas Sensors Array for Volatile Organic Compounds (VOCs

Directory of Open Access Journals (Sweden)

Marcello Mascini

2018-04-01

Full Text Available In this work a peptide based gas sensor array based of ZnO nanoparticles (ZnONPs has been realized. Four different pentapeptides molecularly modeled for alcohols and esters having cysteine as a common spacer have been immobilized onto ZnONPs. ZnONPs have been morphologically and spectroscopically characterized. Modified nanoparticles have been then deposited onto quartz crystal microbalances (QCMs and used as gas sensors with nitrogen as carrier gas. Analysis of the pure compounds modeled demonstrated a nice fitting of modeling with real data. The peptide based ZnONPs had very low sensitivity to water, compared to previously studied AuNPs peptide based gas sensors allowing the use of the array on samples with high water content. Real samples of fruit juices have been assayed; stability of the signal, good repeatability, and discrimination ability of the array was achieved.

Estabilidad de puentes líquidos axilsimétricos

OpenAIRE

Gómez López, Mariola

2011-01-01

En este trabajo se ha realizado una descripción analítica detallada de los límites de estabilidad (tanto de máximo como de mínimo volumen) de puentes líquidos axilsimétricos entre dos discos coaxiales y circulares, en ausencia de fuerzas exteriores sometidos a perturbaciones arbitrarias. Se ha obtenido una parametrización de la entrefase de las formas de equilibrio marginalmente estables, así como expresiones analíticas de los parámetros característicos de la configuración, en términos de var...

Structure-activity-based design of a synthetic malaria peptide eliciting sporozoite inhibitory antibodies in a virosomal formulation.

NARCIS (Netherlands)

Okitsu, S.L.; Kienzl, U.; Moehle, K.; Silvie, O.; Peduzzi, E.; Mueller, M.S.; Sauerwein, R.W.; Matile, H.; Zurbriggen, R.; Mazier, D.; Robinson, J.A.; Pluschke, G.

2007-01-01

The circumsporozoite protein (CSP) of Plasmodium falciparum is a leading candidate antigen for inclusion in a malaria subunit vaccine. We describe here the design of a conformationally constrained synthetic peptide, designated UK-39, which has structural and antigenic similarity to the NPNA-repeat

Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells.

Science.gov (United States)

Oufir, Mouhssin; Bisset, Leslie R; Hoffmann, Stefan R K; Xue, Gongda; Klauser, Stephan; Bergamaschi, Bianca; Gervaix, Alain; Böni, Jürg; Schüpbach, Jörg; Gutte, Bernd

2011-01-01

An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

Análisis bibliométrico de las publicaciones sobre síndrome metabólico en dos revistas biomédicas colombianas de alto impacto

OpenAIRE

María Alejandra Recio; Nathalie Yepes; Freddy Moreno

2017-01-01

Objetivo: Realizar un análisis bibliométrico de las publicaciones sobre síndrome metabólico (SM) en las dos revistas biomédicas colombianas de mayor impacto. Materiales y métodos: Estudio descriptivo documental que realizó un análisis bibliométrico de las publicaciones sobre SM en las revistas Biomédica y Colombia Médica. Para el análisis se emplearon indicadores bibliométricos (tipo de artículo, año de publicación, información de los autores, universidad, tipo de universidad, ciudad, país, á...

Highly Stable Trypsin-Aggregate Coatings on Polymer Nanofibers for Repeated Protein Digestion

Energy Technology Data Exchange (ETDEWEB)

Kim, Byoung Chan; Lopez-Ferrer, Daniel; Lee, Sang-mok; Ahn, Hye-kyung; Nair, Sujith; Kim, Seong H.; Kim, Beom S.; Petritis, Konstantinos; Camp, David G.; Grate, Jay W.; Smith, Richard D.; Koo, Yoon-mo; Gu, Man Bock; Kim, Jungbae

2009-04-01

A stable and robust trypsin-based biocatalytic system was developed and demonstrated for proteomic applications. The system utilizes polymer nanofibers coated with trypsin aggregates for immobilized protease digestions. After covalently attaching an initial layer of trypsin to the polymer nanofibers, highly concentrated trypsin molecules are crosslinked to the layered trypsin by way of a glutaraldehyde treatment. This new process produced a 300-fold increase in trypsin activity compared with a conventional method for covalent trypsin immobilization and proved to be robust in that it still maintained a high level of activity after a year of repeated recycling. This highly stable form of immobilized trypsin was also resistant to autolysis, enabling repeated digestions of bovine serum albumin over 40 days and successful peptide identification by LC-MS/MS. Finally, the immobilized trypsin was resistant to proteolysis when exposed to other enzymes (i.e. chymotrypsin), which makes it suitable for use in “real-world” proteomic applications. Overall, the biocatalytic nanofibers with enzyme aggregate coatings proved to be an effective approach for repeated and automated protein digestion in proteomic analyses.

Development of short and highly potent self-assembling elastin-derived pentapeptide repeats containing aromatic amino acid residues.

Science.gov (United States)

Taniguchi, Suguru; Watanabe, Noriko; Nose, Takeru; Maeda, Iori

2016-01-01

Tropoelastin is the primary component of elastin, which forms the elastic fibers that make up connective tissues. The hydrophobic domains of tropoelastin are thought to mediate the self-assembly of elastin into fibers, and the temperature-mediated self-assembly (coacervation) of one such repetitive peptide sequence (VPGVG) has been utilized in various bio-applications. To elucidate a mechanism for coacervation activity enhancement and to develop more potent coacervatable elastin-derived peptides, we synthesized two series of peptide analogs containing an aromatic amino acid, Trp or Tyr, in addition to Phe-containing analogs and tested their functional characteristics. Thus, position 1 of the hydrophobic pentapeptide repeat of elastin (X(1)P(2)G(3)V(4)G(5)) was substituted by Trp or Tyr. Eventually, we acquired a novel, short Trp-containing elastin-derived peptide analog (WPGVG)3 with potent coacervation ability. From the results obtained during this process, we determined the importance of aromaticity and hydrophobicity for the coacervation potency of elastin-derived peptide analogs. Generally, however, the production of long-chain synthetic polypeptides in quantities sufficient for commercial use remain cost-prohibitive. Therefore, the identification of (WPGVG)3, which is a 15-mer short peptide consisting simply of five natural amino acids and shows temperature-dependent self-assembly activity, might serve as a foundation for the development of various kinds of biomaterials. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

Impacto Pronóstico de los Síndromes Geriátricos en Pacientes Ancianos con Síndrome Coronario Agudo

OpenAIRE

Bonanad Lozano, Clara

2015-01-01

Los síndromes geriátricos pueden predecir eventos adversos en el contexto del síndrome coronario agudo más allá de la propia edad y de los clásicos factores de riesgo cardiovascular. El objetivo de la presente tesis doctoral fue cuantificar y evaluar un amplio espectro de síndromes geriátricos en pacientes supervivientes a la fase aguda de un síndrome coronario. Se incluyeron un total de 342 pacientes mayores de 65 años que ingresaron de forma consecutiva en el servicio de Cardiología de un ú...

La bailoterapia y su influencia en el estilo de vida de los pacientes del Centro Geriátrico Nueva Esperanza

OpenAIRE

Barros Pilay, Carla Rosalía

2011-01-01

El presente proyecto está enmarcado en un estudio analítico acerca de la Bailoterapia y su Influencia en el estilo de vida de los pacientes del Centro Geriátrico Nueva Esperanza, del Cantón Cuenca, Provincia Azuay, cumpliendo con el objetivo general: contribuir al mejoramiento de la salud y calidad de vida de las personas que reciben atención integral en el Centro Geriátrico Nueva Esperanza, manejando adecuadamente la bailoterapia, creando y brindando hábitos en el ámbito físico y recreativo,...

Un análisis econométrico del calentamiento global

OpenAIRE

Corzo Ardila, Hegny Yohana

2016-01-01

El análisis econométrico del calentamiento global no es una tarea sencilla, es necesario tener en cuenta el comportamiento de diversas variables a lo largo del tiempo y las relaciones que existen entre ellas.Teniendo en cuenta que se establecen dos teorías que explican el fenómeno del calentamiento global, los resultados de este análisis demuestran nuestro apoyo a la teoría del calentamiento global antropogenico, es decir causado por la actividad humana descartando un calentamiento de tipo n...

Sistemas microfluídicos amperométricos utilizando enzimas imobilizadas

OpenAIRE

Luís Marcos Cerdeira Ferreira

2011-01-01

Este trabalho descreve o desenvolvimento de um sistema microfluídico, contendo, como componente principal, um reator enzimático constituído de um microcanal fabricado em substrato de poli(metacrilato de metila) e um sistema amperométrico como detector. Para a construção de microcanais foi utilizando equipamento de usinagem a laser de CO2 para escavar os microcanais, que a seguir foram selados termicamente. A superfície interna desse microcanal foi submetida à modificação química com poli(etil...

Tratamiento ortodóntico interceptivo para paciente pediátrico con problema periodontal ocasionado por trauma oclusal primario. Reporte de caso

Directory of Open Access Journals (Sweden)

Johana Maldonado-Villamizar

2016-07-01

Full Text Available El diagnóstico correcto puede evitar la evolución de patologías que lleven al paciente pediátrico a padecer de problemas graves en el futuro. Este diagnóstico junto con un tratamiento interceptivo a tiempo, puede ayudar a resolver problemas de tipo periodontal causado por el inadecuado posicionamiento dental o injurias oclusales. El objetivo de este artículo es realizar el reporte de caso de un paciente pediátrico que presenta una maloclusion dental tipo mordida cruzada anterior acompañada por un trauma oclusal primario, el cual causo un problema periodontal localizado, a su vez, describir la terapéutica interceptiva basada en el correcto diagnóstico odontopediátrico, ortodóntico y periodontal. Concluyendo que al seleccionar la aparatología adecuada se puede solventar diversos problemas dentales que puedan ocasionar un daño mayor a las estructuras comprometidas.

Estrategia para el diseño paramétrico basado en modelos. // Strategy for model-based parametric design.

Directory of Open Access Journals (Sweden)

S. A. Marrero Osorio

2008-09-01

Full Text Available El presente artículo expone una manera de diseñar paramétricamente utilizando los programas de computadora (CAD,CAE, PMS difundidos entre los diseñadores durante los últimos 20 años. La propuesta se basa en modelos matemáticosque consideran el conocimiento sobre la ingeniería del objeto de diseño y lo relacionado con la confección de su modelovirtual tridimensional, planos y otro aspectos; utilizando el Método de los Grafos Dicromáticos para resolver los problemascomputacionales que se presentan en el diseño paramétrico. Se analizan los puntos de vista de diferentes autores en relacióncon el proceso general de diseño y es ubicado dentro del mismo el diseño paramétrico, realizándose una explicación formalque permite arribar a conclusiones interesantes.Palabras claves: Diseño paramétrico, diseño asistido por computadoras (CAD, ingeniería asistida porcomputadoras (CAE, software para el modelado paramétrico (PMS, resolución de problemas._____________________________________________________________________________Abstract:The present article exposes a way to design parametrically applying programs (CAD, CAE, PMS accepted by designers along thelast 20 years. The proposal is based on mathematical models that ponder the knowledge on the engineering of the design object andthe building of its three-dimensional virtual models, blueprints and another aspects; using the dichromatic graph method to solvecomputational problems in parametric design. The points of view of different authors are analyzed in connection with the generalprocess of design, locating parametric design inside it, carrying out a formal explanation which arrives to interesting conclusions.Key words: Parametric design, computer aided design (CAD, computer aided engineering (CAE,parametric modeling software (PMS, problem solving.

Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells

Directory of Open Access Journals (Sweden)

Mouhssin Oufir

2011-01-01

Full Text Available An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

Constitutive expression of transgenes encoding derivatives of the synthetic antimicrobial peptide BP100: impact on rice host plant fitness

Directory of Open Access Journals (Sweden)

Nadal Anna

2012-09-01

Full Text Available Abstract Background The Biopeptide BP100 is a synthetic and strongly cationic α-helical undecapeptide with high, specific antibacterial activity against economically important plant-pathogenic bacteria, and very low toxicity. It was selected from a library of synthetic peptides, along with other peptides with activities against relevant bacterial and fungal species. Expression of the BP100 series of peptides in plants is of major interest to establish disease-resistant plants and facilitate molecular farming. Specific challenges were the small length, peptide degradation by plant proteases and toxicity to the host plant. Here we approached the expression of the BP100 peptide series in plants using BP100 as a proof-of-concept. Results Our design considered up to three tandemly arranged BP100 units and peptide accumulation in the endoplasmic reticulum (ER, analyzing five BP100 derivatives. The ER retention sequence did not reduce the antimicrobial activity of chemically synthesized BP100 derivatives, making this strategy possible. Transformation with sequences encoding BP100 derivatives (bp100der was over ten-fold less efficient than that of the hygromycin phosphotransferase (hptII transgene. The BP100 direct tandems did not show higher antimicrobial activity than BP100, and genetically modified (GM plants constitutively expressing them were not viable. In contrast, inverted repeats of BP100, whether or not elongated with a portion of a natural antimicrobial peptide (AMP, had higher antimicrobial activity, and fertile GM rice lines constitutively expressing bp100der were produced. These GM lines had increased resistance to the pathogens Dickeya chrysanthemi and Fusarium verticillioides, and tolerance to oxidative stress, with agronomic performance comparable to untransformed lines. Conclusions Constitutive expression of transgenes encoding short cationic α-helical synthetic peptides can have a strong negative impact on rice fitness. However, GM

Peptide array-based interaction assay of solid-bound peptides and anchorage-dependant cells and its effectiveness in cell-adhesive peptide design.

Science.gov (United States)

Kato, Ryuji; Kaga, Chiaki; Kunimatsu, Mitoshi; Kobayashi, Takeshi; Honda, Hiroyuki

2006-06-01

Peptide array, the designable peptide library covalently synthesized on cellulose support, was applied to assay peptide-cell interaction, between solid-bound peptides and anchorage-dependant cells, to study objective peptide design. As a model case, cell-adhesive peptides that could enhance cell growth as tissue engineering scaffold material, was studied. On the peptide array, the relative cell-adhesion ratio of NIH/3T3 cells was 2.5-fold higher on the RGDS (Arg-Gly-Asp-Ser) peptide spot as compared to the spot with no peptide, thus indicating integrin-mediated peptide-cell interaction. Such strong cell adhesion mediated by the RGDS peptide was easily disrupted by single residue substitution on the peptide array, thus indicating that the sequence recognition accuracy of cells was strictly conserved in our optimized scheme. The observed cellular morphological extension with active actin stress-fiber on the RGD motif-containing peptide supported our strategy that peptide array-based interaction assay of solid-bound peptide and anchorage-dependant cells (PIASPAC) could provide quantitative data on biological peptide-cell interaction. The analysis of 180 peptides obtained from fibronectin type III domain (no. 1447-1629) yielded 18 novel cell-adhesive peptides without the RGD motif. Taken together with the novel candidates, representative rules of ineffective amino acid usage were obtained from non-effective candidate sequences for the effective designing of cell-adhesive peptides. On comparing the amino acid usage of the top 20 and last 20 peptides from the 180 peptides, the following four brief design rules were indicated: (i) Arg or Lys of positively charged amino acids (except His) could enhance cell adhesion, (ii) small hydrophilic amino acids are favored in cell-adhesion peptides, (iii) negatively charged amino acids and small amino acids (except Gly) could reduce cell adhesion, and (iv) Cys and Met could be excluded from the sequence combination since they have

Albumin-derived peptides efficiently reduce renal uptake of radiolabelled peptides

International Nuclear Information System (INIS)

Vegt, Erik; Eek, Annemarie; Oyen, Wim J.G.; Gotthardt, Martin; Boerman, Otto C.; Jong, Marion de

2010-01-01

In peptide-receptor radionuclide therapy (PRRT), the maximum activity dose that can safely be administered is limited by high renal uptake and retention of radiolabelled peptides. The kidney radiation dose can be reduced by coinfusion of agents that competitively inhibit the reabsorption of radiolabelled peptides, such as positively charged amino acids, Gelofusine, or trypsinised albumin. The aim of this study was to identify more specific and potent inhibitors of the kidney reabsorption of radiolabelled peptides, based on albumin. Albumin was fragmented using cyanogen bromide and six albumin-derived peptides with different numbers of electric charges were selected and synthesised. The effect of albumin fragments (FRALB-C) and selected albumin-derived peptides on the internalisation of 111 In-albumin, 111 In-minigastrin, 111 In-exendin and 111 In-octreotide by megalin-expressing cells was assessed. In rats, the effect of Gelofusine and albumin-derived peptides on the renal uptake and biodistribution of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide was determined. FRALB-C significantly reduced the uptake of all radiolabelled peptides in vitro. The albumin-derived peptides showed different potencies in reducing the uptake of 111 In-albumin, 111 In-exendin and 111 In-minigastrin in vitro. The most efficient albumin-derived peptide (peptide 6), was selected for in vivo testing. In rats, 5 mg of peptide 6 very efficiently inhibited the renal uptake of 111 In-minigastrin, by 88%. Uptake of 111 In-exendin and 111 In-octreotide was reduced by 26 and 33%, respectively. The albumin-derived peptide 6 efficiently inhibited the renal reabsorption of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide and is a promising candidate for kidney protection in PRRT. (orig.)

Synthesis and crystal structure of a homoleptic diruthenium complex containing tetra-2-pyridyl-1,4-pyrazine (tppz)

Energy Technology Data Exchange (ETDEWEB)

Graf, Marion; Mayer, Peter; Boettcher, Hans-Christian [Muenchen Univ. (Germany). Dept. Chemie

2017-07-01

Treatment of hydrated ruthenium(III) chloride with tetra-2-pyridyl-1,4-pyrazine (tppz) in refluxing ethoxyethanol afforded the homoleptic dinuclear complex [(tppz)Ru(μ-tppz)Ru(tppz)]{sup 4+} (1) besides small amounts of the species [Ru(tppz){sub 2}]{sup 2+}. The title complex 1 was obtained as purple crystals and characterized as its hexafluoridophosphate salt by NMR spectroscopy, mass spectrometry and microanalyses. The molecular structure of 1(PF{sub 6}){sub 4} has been established by X-ray crystallography.

Microstructure and nanomechanical properties of enamel remineralized with asparagine-serine-serine peptide

Energy Technology Data Exchange (ETDEWEB)

Chung, Hsiu-Ying, E-mail: hychung@mail.fcu.edu.tw; Li, Cheng Che

2013-03-01

A highly biocompatible peptide, triplet repeats of asparagine-serine-serine (3NSS) was designed to regulate mineral deposition from aqueous ions in saliva for the reconstruction of enamel lesions. Healthy human enamel was sectioned and acid demineralized to create lesions, then exposed to the 3NSS peptide solution, and finally immersed in artificial saliva for 24 h. The surface morphology and roughness were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. X-ray diffraction (XRD) was used to identify the phases and crystallinity of the deposited minerals observed on the enamel surface. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to quantitatively analyze the mineral variation by calculating the relative integrated-area of characteristic bands. Nanohardness and elastic modulus measured by nanoindentation at various treatment stages were utilized to evaluate the degree of recovery. Biomimetic effects were accessed according to the degree of nanohardness recovery and the amount of hydroxyapatite deposition. The charged segments in the 3NSS peptide greatly attracted aqueous ions from artificial saliva to form hydroxyapatite crystals to fill enamel caries, in particular the interrod areas, resulting in a slight reduction in overall surface roughness. Additionally, the deposited hydroxyapatites were of a small crystalline size in the presence of the 3NSS peptide, which effectively restrained the plastic deformations and thus resulted in greater improvements in nanohardness and elastic modulus. The degree of nanohardness recovery was 5 times greater for remineralized enamel samples treated with the 3NSS peptide compared to samples without peptide treatment. - Highlights: Black-Right-Pointing-Pointer The degree of nanohardness recovery of enamel was 4 times greater with the aid of 3NSS peptide. Black-Right-Pointing-Pointer 3NSS peptide promoted the formation of hydroxyapatites with

Interactions of Bio-Inspired Membranes with Peptides and Peptide-Mimetic Nanoparticles

Directory of Open Access Journals (Sweden)

Michael Sebastiano

2015-08-01

Full Text Available Via Dissipative Particle Dynamics (DPD and implicit solvent coarse-grained (CG Molecular Dynamics (MD we examine the interaction of an amphiphilic cell-penetrating peptide PMLKE and its synthetic counterpart with a bio-inspired membrane. We use the DPD technique to investigate the interaction of peptide-mimetic nanoparticles, or nanopins, with a three-component membrane. The CG MD approach is used to investigate the interaction of a cell-penetrating peptide PMLKE with single-component membrane. We observe the spontaneous binding and subsequent insertion of peptide and nanopin in the membrane by using CG MD and DPD approaches, respectively. In addition, we find that the insertion of peptide and nanopins is mainly driven by the favorable enthalpic interactions between the hydrophobic components of the peptide, or nanopin, and the membrane. Our study provides insights into the mechanism underlying the interactions of amphiphilic peptide and peptide-mimetic nanoparticles with a membrane. The result of this study can be used to guide the functional integration of peptide and peptide-mimetic nanoparticles with a cell membrane.

Análise imuno-histoquímica das sintases do óxido nítrico em adenocarcinomas gástricos

OpenAIRE

Begnami,Maria Dirlei F. S.; Cunha,Isabela Werneck da; Montagnini,André; Nonogaki,Sueli; Soares,Fernando

2004-01-01

INTRODUÇÃO: O óxido nítrico (NO) é uma molécula mediadora de diversas funções, tais como vasodilatação, neurotransmissão e metabolismo do ferro. Os efeitos do NO na biologia tumoral são ambíguos e complexos. A atividade das sintases do óxido nítrico (NOS) tem sido demonstrada em diversos tumores humanos. OBJETIVO: Pesquisar a expressão das isoformas das NOS em carcinomas gástricos e correlacionar estes achados com características demográficas e histopatológicas destes tumores. MATERIAL E MÉTO...

Selection of possible signature peptides for the detection of bovine lactoferrin in infant formulas by LC-MS/MS.

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Mingmei Yuan

Full Text Available An LC-MS/MS assay based on a signature peptide was developed and fully validated for the quantitation of bovine lactoferrin in infant formulas. Three unreported signature peptides were derived and identified from the tryptic peptides of bovine lactoferrin. The peptide ETTVFENLPEK was used for quantification based on assay performance. The blank matrix camel milk powder and bovine lactoferrin protein standards were mixed and spiked with stable isotope-labeled internal standard to establish a calibration curve. The established method was extensively validated by determining the linearity (R2 > 0.999, sensitivity (limit of quantitation, 0.16 mg/100 g, recovery (83.1-91.6%, precision (RSD < 5.4% and repeatability (RSD < 7.7%. To validate the applicability of the method, four different brands of infant formulas in China were analysed. The acquired contents of bovine lactoferrin were 52.60-150.56 mg/100 g.

Identification of the bacteria-binding peptide domain on salivary agglutinin (gp-340/DMBT1), a member of the scavenger receptor cysteine-rich superfamily

DEFF Research Database (Denmark)

Bikker, Floris J; Ligtenberg, Antoon J M; Nazmi, Kamran

2002-01-01

Salivary agglutinin is encoded by DMBT1 and identical to gp-340, a member of the scavenger receptor cysteine-rich (SRCR) superfamily. Salivary agglutinin/DMBT1 is known for its Streptococcus mutans agglutinating properties. This 300-400 kDa glycoprotein is composed of conserved peptide motifs: 14...... containing exclusively SRCR and SID domains that binds to S. mutans. To define more closely the S. mutans-binding domain, consensus-based peptides of the SRCR domains and SIDs were designed and synthesized. Only one of the SRCR peptides, designated SRCRP2, and none of the SID peptides bound to S. mutans....... Strikingly, this peptide was also able to induce agglutination of S. mutans and a number of other bacteria. The repeated presence of this peptide in the native molecule endows agglutinin/DMBT1 with a general bacterial binding feature with a multivalent character. Moreover, our studies demonstrate...

A highly sensitive amperometric sensor for oxygen based on iron(II) tetrasulfonated phthalocyanine and iron(III) tetra-(N-methyl-pyridyl)-porphyrin multilayers

International Nuclear Information System (INIS)

Duarte, Juliana C.; Luz, Rita C.S.; Damos, Flavio S.; Tanaka, Auro A.; Kubota, Lauro T.

2008-01-01

The development of a highly sensitive sensor for oxygen is proposed using a glassy carbon (GC) electrode modified with alternated layers of iron(II) tetrasulfonated phthalocyanine (FeTsPc) and iron(III) tetra-(N-methyl-pyridyl)-porphyrin (FeT4MPyP). The modified electrode showed excellent catalytic activity for the oxygen reduction. The reduction potential of the oxygen was shifted about 330 mV toward less negative values with this modified electrode, presenting a peak current much higher than those observed on a bare GC electrode. Cyclic voltammetry and rotating disk electrode (RDE) experiments indicated that the oxygen reduction reaction involves 4 electrons with a heterogenous rate constant (k obs ) of 3 x 10 5 mol -1 L s -1 . A linear response range from 0.2 up to 6.4 mg L -1 , with a sensitivity of 4.12 μA L mg -1 (or 20.65 μA cm -2 L mg -1 ) and a detection limit of 0.06 mg L -1 were obtained with this sensor. The repeatability of the proposed sensor, evaluated in terms of relative standard deviation (R.S.D.) was 2.0% for 10 measurements of a solution of 6.4 mg L -1 oxygen. The sensor was applied to determine oxygen in pond and tap water samples showing to be a promising tool for this purpose

Eletroerosão por fio em metal duro para ferramentas de estampagem de lâminas de motores elétricos

OpenAIRE

Hespanhol, Heber de Carvalho

2009-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Mecânica. O processo de eletroerosão por fio é utilizado atualmente na fabricação da maioria das matrizes e punções de metal duro (carbeto de tungstênio), usados em ferramentas de estampagem de aços para motores elétricos. As indústrias de eletrodomésticos, motores elétricos industriais, transformadores e compressores herméticos, utilizam ferramentas progressivas de...

Nuevas regularidades estructurales de la Cuenca Central (Cuba) a partir de la interpretación cualitativa de datos gravimétricos

OpenAIRE

Jesús A. Blanco-Moreno; José A. Batista-Rodríguez; Aliuska Peña-Reyna

2007-01-01

La Cuenca Central es uno de los lugares de mayor interés geológico y económico de la isla por sus importantes yacimientos de petróleo. Durante la exploración se realizaron levantamientos gravimétricos 1:100 000 cuyos datos se interpretaron cualitativamente teniendo en cuenta resultados de otras áreas. Inicialmente se realizaron transformaciones del campo gravimétrico (Continuación Ascendente y cálculos de gradientes horizontales) y se representaron en mapas de isolineas y de relieve sombreado...

[Plant signaling peptides. Cysteine-rich peptides].

Science.gov (United States)

Ostrowski, Maciej; Kowalczyk, Stanisław

2015-01-01

Recent bioinformatic and genetic analyses of several model plant genomes have revealed the existence of a highly abundant group of signaling peptides that are defined as cysteine-rich peptides (CRPs). CRPs are usually in size between 50 and 90 amino acid residues, they are positively charged, and they contain 4-16 cysteine residues that are important for the correct conformational folding. Despite the structural differences among CRP classes, members from each class have striking similarities in their molecular properties and function. The present review presents the recent progress in research on signaling peptides from several families including: EPF/EPFL, SP11/SCR, PrsS, RALF, LURE, and some other peptides belonging to CRP group. There is convincing evidence indicating multiple roles for these CRPs as signaling molecules during the plant life cycle, ranging from stomata development and patterning, self-incompatibility, pollen tube growth and guidance, reproductive processes, and nodule formation.

Indicadores antropométricos de resistência à insulina Indicadores antropométricos de resistencia a la insulina Anthropometric indicators of insulin resistance

Directory of Open Access Journals (Sweden)

Ana Carolina Vasques

2010-07-01

Full Text Available Alguns estudos têm analisado a eficiência de indicadores antropométricos em predizer resistência à insulina (RI, por serem mais econômicos e acessíveis. Neste estudo, objetivou-se discutir sobre as medidas e índices antropométricos que têm sido associados à RI. Realizou-se um levantamento bibliográfico nas bases Scielo, Science Direct e Pubmed. Dentre os estudos analisados, perímetro da cintura e diâmetro abdominal sagital apresentaram melhor capacidade preditiva para RI, com resultados mais consistentes. As relações cintura/coxa, cintura/estatura, pescoço/coxa, o índice de conicidade e o índice sagital demonstraram resultados positivos, contudo mais estudos são necessários para consolidá-los como preditores de RI. Os resultados obtidos com o uso do índice de massa corporal e da relação cintura/quadril foram mais inconsistentes. Sugere-se a realização de estudos avaliando o desempenho desses indicadores em predizer RI na população brasileira, pois resultados de estudos feitos com outras populações muitas vezes não são aplicáveis à nossa, devido às diferenças étnicas resultantes da grande miscigenação no País.Algunos estudios han analizado la eficiencia de indicadores antropométricos para predecir resistencia a la insulina (RI, por ser más económicos y accesibles. En este estudio, se buscó discutir sobre las medidas e índices antropométricos que han sido asociados a la RI. Se realizó un levantamiento bibliográfico en las bases Scielo, Science Direct y Pubmed. Entre los estudios analizados, perímetro de la cintura y diámetro abdominal sagital presentaron mejor capacidad predictiva para RI, con resultados más consistentes. Las relaciones cintura/muslo, cintura/estatura, cuello/muslo, el índice de conicidad y el índice sagital demostraron resultados positivos, con todo son necesarios más estudios para consolidarlos como predictores de RI. Los resultados obtenidos con el uso del índice de masa

PRINCIPALES ASPECTOS MORFOMÉTRICOS DE LA CIÉNAGA DE CACHIMBERO, SANTANDER – COLOMBIA.

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BENJUMEA HOYOS CARLOS AUGUSTO

2010-05-01

Full Text Available En este artículo se presenta el mapa batimétrico y algunos aspectos morfométricos relevantes de la ciénaga de Cachimbero. Es un sistema tropical somero con profundidad media de 1,83 m. La forma de esta ciénaga, basados en la curva hipsográfica relativa del área frente a la profundidad es cóncava (C. La ciénaga posee altos valores de los parámetros índice de desarrollo del volumen (Vd y la relación de profundidad (cociente profundidad media / profundidad máxima, Dmed / Dmáx, esto refleja su morfometría con un fondo relativamente plano y pendientes pronunciadas desde las orillas hacia el fondo. La ciénaga es de tipo alargado, característica que es corroborada con el índice de desarrollo del perímetro o de la línea costera (F, el cual es superior a la unidad. El valor de este parámetro indica la gran influencia de los factores externos sobre la dinámica de la ciénaga.

A Flow Cytometry Protocol to Estimate DNA Content in the Yellowtail Tetra Astyanax altiparanae

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Pedro L. P. Xavier

2017-09-01

Full Text Available The production of triploid yellowtail tetra Astyanax altiparanae is a key factor to obtain permanently sterile individuals by chromosome set manipulation. Flow cytometric analysis is the main tool for confirmation of the resultant triploids individuals, but very few protocols are specific for A. altiparanae species. The current study has developed a protocol to estimate DNA content in this species. Furthermore, a protocol for long-term storage of dorsal fins used for flow cytometry analysis was established. The combination of five solutions with three detergents (Nonidet P-40 Substitute, Tween 20, and Triton X-100 at 0.1, 0.2, and 0.4% concentration was evaluated. Using the best solution from this first experiment, the addition of trypsin (0.125, 0.25, and 0.5% and sucrose (74 mM and the effects of increased concentrations of the detergents at 0.6 and 1.2% concentration were also evaluated. After adjustment of the protocol for flow cytometry, preservation of somatic tissue or isolated nuclei was also evaluated by freezing (at −20°C and fixation in saturated NaCl solution, acetic methanol (1:3, ethanol, and formalin at 10% for 30 or 60 days of storage at 25°C. Flow cytometry analysis in yellowtail tetra species was optimized using the following conditions: lysis solution: 9.53 mM MgCl2.7H20; 47.67 mM KCl; 15 mM Tris; 74 mM sucrose, 0.6% Triton X-100, pH 8.0; staining solution: Dulbecco's PBS with DAPI 1 μg mL−1; preservation procedure: somatic cells (dorsal fin samples frozen at −20°C. Using this protocol, samples may be stored up to 60 days with good accuracy for flow cytometry analysis.

Physical, mechanical and hydration kinetics of particleboards manufactured with woody biomass (Cupressus lusitanica, Gmelina arborea, Tectona grandis), agricultural resources, and Tetra Pak packages.

Science.gov (United States)

Moya, Róger; Camacho, Diego; Oporto, Gloria S; Soto, Roy F; Mata, Julio S

2014-02-01

Lignocellulosic wastes resulting from agricultural activities as well as Tetra Pak residues from urban centres can cause significant levels of pollution. A possible action to minimize this problem is to use them in the production of particleboards. The purpose of this study was to evaluate the physical, mechanical, and hydration properties of particleboards manufactured with the mixture of woody biomass (Cupressus lusitanica, Gmelina arborea, and Tectona grandis) and either agricultural wastes [pineapple leaves (Ananas comosus) and palm residues (Elaeis guineensis)] or Tetra Pak residues (TP). The results show that the particleboards prepared with TP and woody biomass can reduce the swelling and water absorption in up to 40% and 50% compared with particleboards without TP. Also, these particleboards had increased flexure resistance and shear stress (up to 100%) compared with those without TP. On the contrary, particleboards prepared with pineapple leaves in combination with woody biomass showed the lowest mechanical properties, particularly for tensile strength, hardness, glue-line shear, and nail and screw evaluation.

Polyclonal cell activity of a repeat peptide derived from the sequence of an 85-kilodalton surface protein of Trypanosoma cruzi trypomastigotes.

Science.gov (United States)

Pestel, J; Defoort, J P; Gras-Masse, H; Afchain, D; Capron, A; Tartar, A; Ouaissi, A

1992-01-01

Some in vitro and in vivo biological activities of an octadecapeptide derived from an 85-kDa surface protein of Trypanosoma cruzi trypomastigote were studied. The peptide coupled to a carrier protein induced the proliferative response of lymph node cells from mice immunized with various antigens. Moreover, sera from mice immunized with the coupled peptide were found to contain antibodies against a number of self and nonself antigens: fibronectin, bovine serum albumin, myosin, tetanus toxoid, ovalbumin, keyhole limpet hemocyanin, and DNA. These results are discussed in the context of Chagas' disease immunopathology. PMID:1730508

Human peptide transporters

DEFF Research Database (Denmark)

Nielsen, Carsten Uhd; Brodin, Birger; Jørgensen, Flemming Steen

2002-01-01

Peptide transporters are epithelial solute carriers. Their functional role has been characterised in the small intestine and proximal tubules, where they are involved in absorption of dietary peptides and peptide reabsorption, respectively. Currently, two peptide transporters, PepT1 and PepT2, wh...

Peptide dendrimers

Czech Academy of Sciences Publication Activity Database

Niederhafner, Petr; Šebestík, Jaroslav; Ježek, Jan

2005-01-01

Roč. 11, - (2005), 757-788 ISSN 1075-2617 R&D Projects: GA ČR(CZ) GA203/03/1362 Institutional research plan: CEZ:AV0Z40550506 Keywords : multiple antigen peptides * peptide dendrimers * synthetic vaccine * multipleantigenic peptides Subject RIV: CC - Organic Chemistry Impact factor: 1.803, year: 2005

Peptide-derivatized SB105-A10 dendrimer inhibits the infectivity of R5 and X4 HIV-1 strains in primary PBMCs and cervicovaginal histocultures.

Directory of Open Access Journals (Sweden)

Isabella Bon

Full Text Available Peptide dendrimers are a class of molecules that exhibit a large array of biological effects including antiviral activity. In this report, we analyzed the antiviral activity of the peptide-derivatized SB105-A10 dendrimer, which is a tetra-branched dendrimer synthetized on a lysine core, in activated peripheral blood mononuclear cells (PBMCs that were challenged with reference and wild-type human immunodeficiency virus type 1 (HIV-1 strains. SB105-A10 inhibited infections by HIV-1 X4 and R5 strains, interfering with the early phases of the viral replication cycle. SB105-A10 targets heparan sulfate proteoglycans (HSPGs and, importantly, the surface plasmon resonance (SPR assay revealed that SB105-A10 strongly binds gp41 and gp120, most likely preventing HIV-1 attachment/entry through multiple mechanisms. Interestingly, the antiviral activity of SB105-A10 was also detectable in an organ-like structure of human cervicovaginal tissue, in which SB105-A10 inhibited the HIV-1ada R5 strain infection without altering the tissue viability. These results demonstrated the strong antiviral activity of SB105-A10 and suggest a potential microbicide use of this dendrimer to prevent the heterosexual transmission of HIV-1.

Indicadores antropométricos de estado nutricional como preditores de capacidade em idosos

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Kleyton Trindade Santos

2014-06-01

Full Text Available INTRODUÇÃO: Trata-se de estudo seccional que analisou dados de pesquisa epidemiológica de base populacional e domiciliar conduzida em um município do nordeste do Brasil. OBJETIVO: Identificar os indicadores antropométricos de estado nutricional que apresentam melhor capacidade preditiva de capacidade funcional em idosos. MÉTODOS: A população foi constituída por 316 idosos que foram avaliados por meio de questionário contendo informações sociodemográficas, atividade física e condições de saúde, seguido de avaliação antropométrica. A capacidade funcional foi avaliada por meio das escalas de Katz e de Lawton e Brody para atividades básicas e instrumentais da vida diária, respectivamente. Foram utilizados como indicadores de estado nutricional, o índice de massa corporal, a área muscular do braço e o perímetro da panturrilha. Estimou-se modelos simples e múltiplos de regressão logística multinomial, tendo a capacidade funcional como variável dependente e os indicadores antropométricos como variáveis de interesse. RESULTADOS: Participaram do estudo 173 mulheres (54,7% e 143 homens (45,3%. Os resultados da regressão múltipla mostraram que o perímetro da panturrilha foi o único preditor de capacidade funcional em mulheres (≤ P25: OR = 5,77, p = 0,028, para dependência nas atividades instrumentais, enquanto que nos homens o índice de massa corporal foi o único indicador associado (baixo peso: OR = 11,36, p = 0,006; sobrepeso: OR = 22,06, p = 0,002; para dependência nas atividades básicas e instrumentais. CONCLUSÃO: Os resultados permitem concluir que os indicadores antropométricos preditores de capacidade funcional em idosos variam de acordo com o sexo, com o perímetro da panturrilha sendo mais adequada às mulheres e o índice de massa corporal aos homens.

La resolución de problemas geométricos en Matemática utilizando la computadora

Directory of Open Access Journals (Sweden)

Osmany Guzmán-Simón

2017-11-01

Full Text Available Se presenta un análisis donde se plantean los fundamentos psicopedagógicos que sustentan el desarrollo de habilidades en la resolución de problemas geométricos en la asignatura Matemática, utilizando la computadora.

Vasorelaxing and antihypertensive activities of synthesized peptides derived from computer-aided simulation of pepsin hydrolysis of yam dioscorin.

Science.gov (United States)

Lin, Yin-Shiou; Lu, Yeh-Lin; Wang, Guei-Jane; Liang, Hong-Jen; Hou, Wen-Chi

2014-12-01

We reported that yam dioscorin and its peptic hydrolysates exhibited ACE inhibition and antihypertensive effects on SHRs, however, the active peptides are not really isolated until now. Using ACE inhibitory screenings, two penta-peptides, KTCGY and KRIHF, were selected for ex vivo and in vivo experiments. KTCGY, KRIHF, and captopril were shown to have similar vasodilating effects against phenylephrine (PE)-induced tensions in rat endothelium-dependent thoracic aortic rings, however, KTCGYKTCGY (two-repeated KTCGY) and TCGYTCGY (two-repeated TCGY) were showed endothelium-independent vasodilating effects against PE-induced tensions. KTCGY, KRIHF (10 or 20 mg/kg), and captopril (10 mg/kg) were used to evaluate antihypertensive activity during 24-h after a single oral administration to spontaneously hypertensive rats (SHRs). The KTCGY and KRIHF showed significantly different and reduced the systolic blood pressure of SHRs compared to the blank. These results suggest that KTCGY and KRIHF may contribute important roles in yam dioscorin for regulating blood pressure in vivo.

TMPyP4 porphyrin distorts RNA G-quadruplex structures of the disease-associated r(GGGGCC)n repeat of the C9orf72 gene and blocks interaction of RNA-binding proteins.

Science.gov (United States)

Zamiri, Bita; Reddy, Kaalak; Macgregor, Robert B; Pearson, Christopher E

2014-02-21

Certain DNA and RNA sequences can form G-quadruplexes, which can affect genetic instability, promoter activity, RNA splicing, RNA stability, and neurite mRNA localization. Amyotrophic lateral sclerosis and frontotemporal dementia can be caused by expansion of a (GGGGCC)n repeat in the C9orf72 gene. Mutant r(GGGGCC)n- and r(GGCCCC)n-containing transcripts aggregate in nuclear foci, possibly sequestering repeat-binding proteins such as ASF/SF2 and hnRNPA1, suggesting a toxic RNA pathogenesis, as occurs in myotonic dystrophy. Furthermore, the C9orf72 repeat RNA was recently demonstrated to undergo the noncanonical repeat-associated non-AUG translation (RAN translation) into pathologic dipeptide repeats in patient brains, a process that is thought to depend upon RNA structure. We previously demonstrated that the r(GGGGCC)n RNA forms repeat tract length-dependent G-quadruplex structures that bind the ASF/SF2 protein. Here we show that the cationic porphyrin (5,10,15,20-tetra(N-methyl-4-pyridyl) porphyrin (TMPyP4)), which can bind some G-quadruplex-forming sequences, can bind and distort the G-quadruplex formed by r(GGGGCC)8, and this ablates the interaction of either hnRNPA1 or ASF/SF2 with the repeat. These findings provide proof of concept that nucleic acid binding small molecules, such as TMPyP4, can distort the secondary structure of the C9orf72 repeat, which may beneficially disrupt protein interactions, which may ablate either protein sequestration and/or RAN translation into potentially toxic dipeptides. Disruption of secondary structure formation of the C9orf72 RNA repeats may be a viable therapeutic avenue, as well as a means to test the role of RNA structure upon RAN translation.

Development and use of engineered peptide deformylase in chemoenzymatic peptide synthesis

NARCIS (Netherlands)

Di Toma, Claudia

2012-01-01

Deze thesis beschrijft het onderzoek naar potentieel van het gebruik van het peptide deformylase (PDF) in chemo enzymatische peptide synthese. PDF is geschikt voor selective N terminale deformylatie van bepaalde N-formyl-peptides zonder gelijktijdige hydrolyse van de peptide binding. Door de

Rediseño paramétrico del pendubot para posicionamiento vertical en tiempo mínimo

Directory of Open Access Journals (Sweden)

Carlos A. Cruz-Villar

2008-01-01

Full Text Available Resumen: Se propone Una metodología de rediseilo paramétrico de sistema no lineales para control en tiempo mínimo sin restricciones de trayectoria en losestados y con control a.cotado. Tal metodología. consiste en plantear el problema de rediseño óptimo como uno de optimización dinámica, permitiendo encontrar simultáneamente los parámetros estructurales del sistema y los instantes de conrnlltación de la señal de control que minimizan el tiempo requerido para llevar al sistema de un estado inicial a uno final. Se muestran resultados experimentales del Pendubot original con control en tiempo mínimo y del Pendubot rediseñado siguiendo la metodología propuesta. Palabras clave: Diseño integrado, Rediserlo paramétrico, Optimización dinámica, Pendubot, Tiempo mínimo

Design, synthesis and antiproliferative activity of hydroxyacetamide ...

African Journals Online (AJOL)

benzamides, the cyclic tetra peptides, the carboxylic acids and ... previously prepared methanol solution of 0.0501. M, 2.81 g .... acid were suspended in 0.066 M glacial acetic acid solution. The mixture was refluxed for 2 h under water bath.

Two Organic Cation Salts Containing Tetra(isothiocyanatecobaltate(II: Synthesis, Crystal Structures, Spectroscopic, Optical and Magnetic Properties

Directory of Open Access Journals (Sweden)

Zheng Zhang

2017-03-01

Full Text Available Single crystals of two hybrid organic-inorganic molecular solids, benzyl pyridinium tetra(isothiocyanatecobalt ([BzPy]2[Co(NCS4] (1 and benzyl quinolinium tetra(isothiocyanatecobalt ([BzQl]2[Co(NCS4] (2, were grown using a slow evaporation growth technique at room temperature and their IR, UV-Vis, X-ray crystal structures, luminescence, and magnetism were reported. The crystal structural analysis revealed that two molecular solids crystallize in the monoclinic space group P21/c of 1 and P21/n of 2. The cations form a dimer through weak C–H···π/π···π interactions in 1 and 2, and the adjacent cation (containing N(6 atom in 2 forms a columnar structure through π···π weak interactions between the quinoline and benzene rings, while the anions in 1 form a layer structure via short S···Co interactions. The anions (A and cations (C are arranged alternatively into a column in the sequence of ···A–CC–A–CC–A··· for 1, while the two anions and cationic dimer in 2 form an alliance by the C–H···π, C–H···S and C–H···N hydrogen bonds. A weak S···π interaction was found in 1 and 2. The two molecular solids show a broad fluorescence emission around 400 nm in the solid state at room temperature, and weak antiferromagnetic coupling behavior when the temperature is lowered.

Photodynamic inactivation of Candida albicans sensitized by tri- and tetra-cationic porphyrin derivatives.

Science.gov (United States)

Cormick, M Paula; Alvarez, M Gabriela; Rovera, Marisa; Durantini, Edgardo N

2009-04-01

The photodynamic action of 5-(4-trifluorophenyl)-10,15,20-tris(4-trimethylammoniumphenyl)porphyrin iodide (TFAP(3+)) and 5,10,15,20-tetra(4-N,N,N-trimethylammonium phenyl)porphyrin p-tosylate (TMAP(4+)) has been studied in vitro on Candida albicans. The results of these cationic porphyrins were compared with those of 5,10,15,20-tetra(4-sulphonatophenyl)porphyrin (TPPS(4-)), which characterizes an anionic sensitizer. In vitro investigations show that these cationic porphyrins are rapidly bound to C. albicans cells, reaching a value of approximately 1.4 nmol/10(6) cells, when the cellular suspensions were incubated with 5 microM sensitizer for 30 min. In contrast, TPPS(4-) is poorly uptaken by yeast cells. The fluorescence spectra of these sensitizers into the cells confirm this behaviour. The amount of porphyrin binds to cells is dependent on both sensitizer concentrations (1-5 microM) and cells densities (10(6)-10(8) cells/mL). Photosensitized inactivation of C. albicans cellular suspensions increases with sensitizer concentration, causing a approximately 5 log decrease of cell survival, when the cultures are treated with 5 microM of cationic porphyrin and irradiated for 30 min. However, the photocytotoxicity decreases with an increase in the cell density, according to its low binding to cells. Under these conditions, the photodynamic activity of TFAP(3+) is quite similar to that produced by TMAP(4+), whereas no important inactivation effect was found for TPPS(4)(-). The high photodynamic activity of cationic porphyrins was confirmed by growth delay experiments. Thus, C. albicans cell growth was not detected in the presence of 5 microM TFAP(3+). Photodynamic inactivation capacities of these sensitizers were also evaluated on C. albicans cells growing in colonies on agar surfaces. Cationic porphyrins produce a growth delay of C. albicans colonies and viability of cells was not observed after 3 h irradiation, indicating a complete inactivation of yeast cells

Analysis of simple sequence repeats in the Gaeumannomyces graminis var. tritici genome and the development of microsatellite markers.

Science.gov (United States)

Li, Wei; Feng, Yanxia; Sun, Haiyan; Deng, Yuanyu; Yu, Hanshou; Chen, Huaigu

2014-11-01

Understanding the genetic structure of Gaeumannomyces graminis var. tritici is essential for the establishment of efficient disease control strategies. It is becoming clear that microsatellites, or simple sequence repeats (SSRs), play an important role in genome organization and phenotypic diversity, and are a large source of genetic markers for population genetics and meiotic maps. In this study, we examined the G. graminis var. tritici genome (1) to analyze its pattern of SSRs, (2) to compare it with other plant pathogenic filamentous fungi, such as Magnaporthe oryzae and M. poae, and (3) to identify new polymorphic SSR markers for genetic diversity. The G. graminis var. tritici genome was rich in SSRs; a total 13,650 SSRs have been identified with mononucleotides being the most common motifs. In coding regions, the densities of tri- and hexanucleotides were significantly higher than in noncoding regions. The di-, tri-, tetra, penta, and hexanucleotide repeats in the G. graminis var. tritici genome were more abundant than the same repeats in M. oryzae and M. poae. From 115 devised primers, 39 SSRs are polymorphic with G. graminis var. tritici isolates, and 8 primers were randomly selected to analyze 116 isolates from China. The number of alleles varied from 2 to 7 and the expected heterozygosity (He) from 0.499 to 0.837. In conclusion, SSRs developed in this study were highly polymorphic, and our analysis indicated that G. graminis var. tritici is a species with high genetic diversity. The results provide a pioneering report for several applications, such as the assessment of population structure and genetic diversity of G. graminis var. tritici.

New dendrimer - Peptide host - Guest complexes: Towards dendrimers as peptide carriers

DEFF Research Database (Denmark)

Boas, Ulrik; Sontjens, S.H.M.; Jensen, Knud Jørgen

2002-01-01

Adamantyl urea and adamantyl thiourea modified poly(propylene imine) dendrimers act as hosts for N-terminal tert-butoxycarbonyl (Boc)-protected peptides and form chloroform-soluble complexes. investigations with NMR spectroscopy show that the peptide is bound to the dendrimer by ionic interactions...... between the dendrimer outer shell tertiary amines and the C-terminal carboxylic acid of the peptide, and also through host-urea to peptide-amide hydrogen bonding. The hydrogen-bonding nature of the peptide dendrimer interactions was further confirmed by using Fourier transform IR spectroscopy, for which...... the NH- and CO-stretch signals of the peptide amide moieties shift towards lower wave-numbers upon complexation with the dendrimer. Spatial analysis of the complexes with NOESY spectroscopy generally shows close proximity of the N-terminal Boc group of the peptide to the peripheral adamantyl groups...

Ga+ TOF-SIMS lineshape analysis for resolution enhancement of MALDI MS spectra of a peptide mixture

International Nuclear Information System (INIS)

Malyarenko, D.I.; Chen, H.; Wilkerson, A.L.; Tracy, E.R.; Cooke, W.E.; Manos, D.M.; Sasinowski, M.; Semmes, O.J.

2004-01-01

The use of mass spectrometry to obtain molecular profiles indicative of alteration of concentrations of peptides in body fluids is currently the subject of intense investigation. For surface-based time-of-flight mass spectrometry the reliability and specificity of such profiling methods depend both on the resolution of the measuring instrument and on the preparation of samples. The present work is a part of a program to use Ga + beam TOF-SIMS alone, and as an adjunct to MALDI, in the development of reliable protein and peptide markers for diseases. Here, we describe techniques to prepare samples of relatively high-mass peptides, which serve as calibration standards and proxies for biomarkers. These are: Arg8-vasopressin, human angiotensin II, and somatostatin. Their TOF-SIMS spectra show repeatable characteristic features, with mass resolution exceeding 2000, including parent peaks and chemical adducts. The lineshape analysis for high-resolution parent peaks is shown to be useful for filter construction and deconvolution of inferior resolution SELDI-TOF spectra of calibration peptide mixture

Characterization of the branched antimicrobial peptide M6 by analyzing its mechanism of action and in vivo toxicity.

Science.gov (United States)

Pini, Alessandro; Giuliani, Andrea; Falciani, Chiara; Fabbrini, Monica; Pileri, Silvia; Lelli, Barbara; Bracci, Luisa

2007-06-01

We analyzed functional activity of the antimicrobial peptide M6 in vitro and in vivo. The peptide was identified by our group by phage library selection, rational modification and synthesis in a tetrabranched form (Pini et al., Antimicrob. Agents Chemother. 2005; 49: 2665-72). We found that it binds lipopolysaccharide, causes perforation of cell membranes without destroying external cell morphology and strongly binds DNA. The latter feature suggests that it could inhibit metabolic pathways, blocking DNA replication and/or transcription. We also observed that M6 does not stimulate humoral immune response when repeatedly administered to animals. We also analyzed M6 toxicity when administered to animals by intraperitoneal or by intravenous injection, determining a preliminary LD50 (125 and 37.5 mg/kg, respectively), which suggested that M6 could be used in vivo. These features make the antimicrobial branched peptide M6 a promising candidate for the development of a new antibacterial drug. Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd.

Folding control in cyclic peptides through N-methylation pattern selection: formation of antiparallel beta-sheet dimers, double reverse turns and supramolecular helices by 3alpha,gamma cyclic peptides.

Science.gov (United States)

Amorín, Manuel; Castedo, Luis; Granja, Juan R

2008-01-01

Peptide foldamers constitute a growing class of nanomaterials with potential applications in a wide variety of chemical, medical and technological fields. Here we describe the preparation and structural characteristics of a new class of cyclic peptide foldamers (3alpha,gamma-CPs) that, depending on their backbone N-methylation patterns and the medium, can either remain as flat rings that dimerize through arrays of hydrogen bonds of antiparallel beta-sheet type, or can fold into twisted double reverse turns that, in the case of double gamma-turns, associate in nonpolar solvents to form helical supramolecular structures. A 3alpha,gamma-CP consists of a number of multiples of a repeat unit made up of four amino acid residues of alternating chirality: three corresponding to alpha-amino acids and one to a gamma-amino acid (a cis-3-aminocycloalkanecarboxylic acid).

El perfil antropométrico de la gimnasia rítmica

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Beatriz Romero Quintero

2011-03-01

Full Text Available El estudio realizado pretende analizar el biotipo de la gimnasta de rítmica, relacionar su rendimiento de competición con algunos valores de la condición física y valores antropométricos. La comparativa se ha realizado mediante la técnica de árboles de clasificación, significando la pertenencia de club, el pliegue suprailíaco, el pliegue del muslo y el salto vertical como favorables de buenos resultados. El salto específico “gacela” presenta valores inferiores respecto al salto vertical.

Electrochemical behavior of free-radical derivatives of tetra(4hydroxyl-3,5-di-tert-butylphenyl) porphyrin

Energy Technology Data Exchange (ETDEWEB)

Pokhodenko, V.D.; Melezhik, A.V.; Platonova, E.P.; Vovk, D.N.

1984-08-01

The electrochemical behavior of free-radical derivatives of tetra(4hydroxyl-3,5-di-tert-butylphenyl) porphyrins and their complexes with Mg(II), Zn(II), Ni(II), CU(II), and Pd(II) ions was studied by the methods of voltamperometry, ESR, and spectrophotometry. It was shown that the introduction of free-radical substituents into the porphin macrocycle leads to a substantial decrease in the oxidation and reduction potentials of the complexes. The degree of conjunction of substituents with the porphin macrocycle is estimated according to the difference of the redox potentials of free-radical and quinoid derivatives of metalloporphyrins.

A novel asymmetric chair-like hydroxyl-bridged tetra-copper compound: Synthesis, supramolecular structure and magnetic property

Science.gov (United States)

Wang, Xiao-Feng; Du, Ke-Jie; Wang, Hong-Qing; Zhang, Xue-Li; Nie, Chang-Ming

2017-06-01

A new polynuclear Cu(II) compound, [Cu4(bpy)4(OH)4(H2O)(BTC)]NO3·8H2O (1), was prepared by self-assembly from the solution of copper(II) nitrate and two kinds of ligands, 2,2‧-bipyridine (bpy) and benzene-tricarboxylic acid (H3BTC). Single crystal structure analysis reveals that 1 features a rare asymmetric chair-like hydroxyl-bridged tetra-copper cluster: [Cu4(OH)4] core along with one H2O and one BTC3- occupied each terminal coordinated site. In addition, the magnetic property has been investigated.

Adolescentes em tratamento psiquiátrico: um estudo fenomenológico das vivências em seus relacionamentos sócio-afetivos-sexuais

OpenAIRE

Fernanda Tomé Marleta Iezzi

2013-01-01

RESUMO Marleta-Iezzi, F. T. (2013) Adolescentes em tratamento psiquiátrico: um estudo fenomenológico das vivências em seus relacionamentos sócio-afetivo-sexuais. Dissertação de Mestrado Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da Universidade de São Paulo, Ribeirão Preto. Na presente dissertação buscamos situar e (re)conhecer o fenômeno das vivências dos relacionamentos sócio-afetivo-sexuais de adolescentes submetidos a tratamento psiquiátrico, por compreender que a adol...

Gene Therapy Vectors with Enhanced Transfection Based on Hydrogels Modified with Affinity Peptides

Science.gov (United States)

Shepard, Jaclyn A.; Wesson, Paul J.; Wang, Christine E.; Stevans, Alyson C.; Holland, Samantha J.; Shikanov, Ariella; Grzybowski, Bartosz A.; Shea, Lonnie D.

2011-01-01

Regenerative strategies for damaged tissue aim to present biochemical cues that recruit and direct progenitor cell migration and differentiation. Hydrogels capable of localized gene delivery are being developed to provide a support for tissue growth, and as a versatile method to induce the expression of inductive proteins; however, the duration, level, and localization of expression isoften insufficient for regeneration. We thus investigated the modification of hydrogels with affinity peptides to enhance vector retention and increase transfection within the matrix. PEG hydrogels were modified with lysine-based repeats (K4, K8), which retained approximately 25% more vector than control peptides. Transfection increased 5- to 15-fold with K8 and K4 respectively, over the RDG control peptide. K8- and K4-modified hydrogels bound similar quantities of vector, yet the vector dissociation rate was reduced for K8, suggesting excessive binding that limited transfection. These hydrogels were subsequently applied to an in vitro co-culture model to induce NGF expression and promote neurite outgrowth. K4-modified hydrogels promoted maximal neurite outgrowth, likely due to retention of both the vector and the NGF. Thus, hydrogels modified with affinity peptides enhanced vector retention and increased gene delivery, and these hydrogels may provide a versatile scaffold for numerous regenerative medicine applications. PMID:21514659

A reforma do setor elétrico no Brasil, Argentina e México: contrastes e perspectivas em debate

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Alessandro André Leme

2009-06-01

Full Text Available A década de 1990 foi marcada por um movimento global de Reformas do Estado, principalmente nos países em desenvolvimento. Nesse processo, as orientações das agências multilaterais fizeram-se mais presentes. O conjunto de reformas liberalizantes transferiu para o setor privado setores até então em mãos do Estado. Dentre esses setores destacamos o caso da infra-estrutura energética. O setor elétrico no Brasil, na Argentina e no México consolidou-se após a II Guerra Mundial, sendo majoritariamente ligado ao Estado. Na década de 1990, nesses três países, esse setor passa por mudanças privatizantes. O quadro de fundo (plano político-econômico era muito similar entre os países, embora preservassem particularidades econômicas e político-institucionais. A crise de hiperinflação na década de 1980 e as fortes pressões dos organismos multilaterais para a realização de reformas para o mercado (privatização e flexibilização, dentre outros aspectos levou a mudanças no setor elétrico desses países. Partimos, neste trabalho, de uma abordagem histórico-estrutural e estratégica. Analisamos as reformas no setor elétrico brasileiro em diálogo com as ocorridas na Argentina e no México. Concluímos definindo as principais semelhanças e diferenças entre as políticas liberalizantes do setor elétrico no Brasil, Argentina e México e delimitamos os principais fatores dessas variações, ressaltando a não existência de unicidade histórica na escolhas de estratégias, mas sim composição de estratégias de desenvolvimento decorrentes do embate entre as diversas forças políticas presentes e atuantes num determinado espaço (Estado com suas variantes nacionais e internacionais.

Evidence that C9ORF72 Dipeptide Repeat Proteins Associate with U2 snRNP to Cause Mis-splicing in ALS/FTD Patients.

Science.gov (United States)

Yin, Shanye; Lopez-Gonzalez, Rodrigo; Kunz, Ryan C; Gangopadhyay, Jaya; Borufka, Carl; Gygi, Steven P; Gao, Fen-Biao; Reed, Robin

2017-06-13

Hexanucleotide repeat expansion in the C9ORF72 gene results in production of dipeptide repeat (DPR) proteins that may disrupt pre-mRNA splicing in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) patients. At present, the mechanisms underlying this mis-splicing are not understood. Here, we show that addition of proline-arginine (PR) and glycine-arginine (GR) toxic DPR peptides to nuclear extracts blocks spliceosome assembly and splicing, but not other types of RNA processing. Proteomic and biochemical analyses identified the U2 small nuclear ribonucleoprotein particle (snRNP) as a major interactor of PR and GR peptides. In addition, U2 snRNP, but not other splicing factors, mislocalizes from the nucleus to the cytoplasm both in C9ORF72 patient induced pluripotent stem cell (iPSC)-derived motor neurons and in HeLa cells treated with the toxic peptides. Bioinformatic studies support a specific role for U2-snRNP-dependent mis-splicing in C9ORF72 patient brains. Together, our data indicate that DPR-mediated dysfunction of U2 snRNP could account for as much as ∼44% of the mis-spliced cassette exons in C9ORF72 patient brains. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Evidence that C9ORF72 Dipeptide Repeat Proteins Associate with U2 snRNP to Cause Mis-splicing in ALS/FTD Patients

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Shanye Yin

2017-06-01

Full Text Available Hexanucleotide repeat expansion in the C9ORF72 gene results in production of dipeptide repeat (DPR proteins that may disrupt pre-mRNA splicing in amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD patients. At present, the mechanisms underlying this mis-splicing are not understood. Here, we show that addition of proline-arginine (PR and glycine-arginine (GR toxic DPR peptides to nuclear extracts blocks spliceosome assembly and splicing, but not other types of RNA processing. Proteomic and biochemical analyses identified the U2 small nuclear ribonucleoprotein particle (snRNP as a major interactor of PR and GR peptides. In addition, U2 snRNP, but not other splicing factors, mislocalizes from the nucleus to the cytoplasm both in C9ORF72 patient induced pluripotent stem cell (iPSC-derived motor neurons and in HeLa cells treated with the toxic peptides. Bioinformatic studies support a specific role for U2-snRNP-dependent mis-splicing in C9ORF72 patient brains. Together, our data indicate that DPR-mediated dysfunction of U2 snRNP could account for as much as ∼44% of the mis-spliced cassette exons in C9ORF72 patient brains.

Amide I SFG Spectral Line Width Probes the Lipid-Peptide and Peptide-Peptide Interactions at Cell Membrane In Situ and in Real Time.

Science.gov (United States)

Zhang, Baixiong; Tan, Junjun; Li, Chuanzhao; Zhang, Jiahui; Ye, Shuji

2018-06-13

The balance of lipid-peptide and peptide-peptide interactions at cell membrane is essential to a large variety of cellular processes. In this study, we have experimentally demonstrated for the first time that sum frequency generation vibrational spectroscopy can be used to probe the peptide-peptide and lipid-peptide interactions in cell membrane in situ and in real time by determination of the line width of amide I band of protein backbone. Using a "benchmark" model of α-helical WALP23, it is found that the dominated lipid-peptide interaction causes a narrow line width of the amide I band, whereas the peptide-peptide interaction can markedly broaden the line width. When WALP23 molecules insert into the lipid bilayer, a quite narrow line width of the amide I band is observed because of the lipid-peptide interaction. In contrast, when the peptide lies down on the bilayer surface, the line width of amide I band becomes very broad owing to the peptide-peptide interaction. In terms of the real-time change in the line width, the transition from peptide-peptide interaction to lipid-peptide interaction is monitored during the insertion of WALP23 into 1,2-dipalmitoyl- sn-glycero-3-phospho-(1'- rac-glycerol) (DPPG) lipid bilayer. The dephasing time of a pure α-helical WALP23 in 1-palmitoyl-2-oleoyl- sn-glycero-3-phospho-(1'- rac-glycerol) and DPPG bilayer is determined to be 2.2 and 0.64 ps, respectively. The peptide-peptide interaction can largely accelerate the dephasing time.

Genome-scale portrait and evolutionary significance of human-specific core promoter tri- and tetranucleotide short tandem repeats.

Science.gov (United States)

Nazaripanah, N; Adelirad, F; Delbari, A; Sahaf, R; Abbasi-Asl, T; Ohadi, M

2018-04-05

While there is an ongoing trend to identify single nucleotide substitutions (SNSs) that are linked to inter/intra-species differences and disease phenotypes, short tandem repeats (STRs)/microsatellites may be of equal (if not more) importance in the above processes. Genes that contain STRs in their promoters have higher expression divergence compared to genes with fixed or no STRs in the gene promoters. In line with the above, recent reports indicate a role of repetitive sequences in the rise of young transcription start sites (TSSs) in human evolution. Following a comparative genomics study of all human protein-coding genes annotated in the GeneCards database, here we provide a genome-scale portrait of human-specific short- and medium-size (≥ 3-repeats) tri- and tetranucleotide STRs and STR motifs in the critical core promoter region between - 120 and + 1 to the TSS and evidence of skewing of this compartment in reference to the STRs that are not human-specific (Levene's test p human-specific transcripts was detected in the tri and tetra human-specific compartments (mid-p genome-scale skewing of STRs at a specific region of the human genome and a link between a number of these STRs and TSS selection/transcript specificity. The STRs and genes listed here may have a role in the evolution and development of characteristics and phenotypes that are unique to the human species.

Modelos paramétricos y no paramétricos, para la previsión de la volatilidad. Su aplicación al cálculo del valor en riesgo

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Sira Allende Alonso

2005-01-01

Full Text Available Afrontamos aquí el importante reto de la estimación y control del riesgo de mercado, originado por cambios en los precios de acciones, mercancías, tantos de cambio y tantos de interés. Analizamos los modelos internos del Comité de Basilea para la estimación del riesgo de mercado, y se trata de hacer frente al incremento de la volatilidad de los activos financieros para combatir el riesgo. Se usan dos clases de modelos: amodelos iid (independientes e idénticamente distribuidos, no necesariamente gaussianos y bmodelos condicionales gaussianos. Comparamos métodos paramétricos como la aproximación “varianzacovarianza”, los modelos de la media móvil simple (SIM, la media móvil con ponderación exponencial (EWMA y los modelos GARCH, la volatilidad implícita y la Simulación de Monte Carlo para posiciones no lineales. Se tratan de métodos noparamétricos, la simulación histórica y el método “back testing”. Introducimos variantes y aproximaciones del Valor en Riesgo, tales como “stress testing” y el análisis de colas para el “Worse case Scenario analysis” y la “Teoría del valor extremo”. Casos especiales son los modelos EWMA y GARCH.

de Vries liquid crystals based on a chiral 5-phenylpyrimidine benzoate core with a tri- and tetra-carbosilane backbone

Science.gov (United States)

Sreenilayam, S. P.; Rodriguez-Lojo, D.; Agra-Kooijman, D. M.; Vij, J. K.; Panov, V. P.; Panov, A.; Fisch, M. R.; Kumar, Satyendra; Stevenson, P. J.

2018-02-01

New chiral de Vries smectic liquid-crystalline compounds are designed, synthesized, and investigated for perspective applications in defect-free bistable surface-stabilized ferroelectric liquid-crystal displays. In these compounds, a 5-phenyl-pyrimidine benzoate core is terminated on one side by a tri- or tetra-carbosilane group linked through an alkoxy group and an alkyl spacer and on the opposite side terminated by a chiral 2-octanol group. The stereogenic center contains either a methyl or perfluoromethyl functional group. These compounds exhibit Iso-Sm A*-Sm C*-Sm X -Cr phases under cooling from the isotropic state. Measurements of the temperature-dependent smectic layer spacing by x-ray diffraction experiments combined with the measured apparent optical tilt angle and the birefringence reveal that Sm A* phase in these compounds is of the de Vries type. In addition, the chiral compound with a tetra-carbosilane backbone, DR277, exhibits good de Vries properties with the Sm C* phase exhibited over a wide temperature range. By varying the carbosilane end group, the de Vries properties are enhanced, that is, the layer shrinkage of ˜1.9 % for the tri-carbosilane DR276 is reduced to ˜0.9 % for tetra-carbosilane DR277 at 10°C below Sm A* to Sm C* transition temperature, TAC. For DR277, the reduction factor R ≈0.22 for T =(TAC-10 )°C is reasonably low and the apparent optical tilt angle θapp=35.1°, hence this compound is a "good de Vries smectic" LC. Therefore, synthesis of the chiral mesogen with an even higher number of carbosilane groups may lead to a further reduction or even zero-layer shrinkage exhibited at TAC with Sm C* phase extending over a wide temperature range close to the room temperature for perspective suitability in device applications. Our results for 5-phenyl-pyrimidine benzoate core-based compounds support a recently drawn conclusion by Schubert et al. [J. Mater. Chem. C 4, 8483 (2016), 10.1039/C6TC03120J] from a different compound, namely

Taylor Dispersion Analysis as a promising tool for assessment of peptide-peptide interactions.

Science.gov (United States)

Høgstedt, Ulrich B; Schwach, Grégoire; van de Weert, Marco; Østergaard, Jesper

2016-10-10

Protein-protein and peptide-peptide (self-)interactions are of key importance in understanding the physiochemical behavior of proteins and peptides in solution. However, due to the small size of peptide molecules, characterization of these interactions is more challenging than for proteins. In this work, we show that protein-protein and peptide-peptide interactions can advantageously be investigated by measurement of the diffusion coefficient using Taylor Dispersion Analysis. Through comparison to Dynamic Light Scattering it was shown that Taylor Dispersion Analysis is well suited for the characterization of protein-protein interactions of solutions of α-lactalbumin and human serum albumin. The peptide-peptide interactions of three selected peptides were then investigated in a concentration range spanning from 0.5mg/ml up to 80mg/ml using Taylor Dispersion Analysis. The peptide-peptide interactions determination indicated that multibody interactions significantly affect the PPIs at concentration levels above 25mg/ml for the two charged peptides. Relative viscosity measurements, performed using the capillary based setup applied for Taylor Dispersion Analysis, showed that the viscosity of the peptide solutions increased with concentration. Our results indicate that a viscosity difference between run buffer and sample in Taylor Dispersion Analysis may result in overestimation of the measured diffusion coefficient. Thus, Taylor Dispersion Analysis provides a practical, but as yet primarily qualitative, approach to assessment of the colloidal stability of both peptide and protein formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Risco, trabalho e masculinidade. Um estudo sobre os trabalhadores do setor elétrico

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Julice Salvagni

2013-12-01

Full Text Available Este estudo é parte de uma dissertação de mestrado (2011 que abordou aspectos referentes ao risco de trabalho no setor elétrico. Neste artigo, dá-se ênfase a uma análise sobre as noções de subjetivação da masculinidade que perpassam a realidade de trabalho dos eletricitários e que estão diretamente relacionadas ao entendimento de risco de acidentes. Para além do risco de acidentes físicos, compreende-se que os riscos se constituem na esfera do invisível (fatores sócio-psicológicos. Destacam-se elementos de ordem subjetiva que constituem a relação dos trabalhadores com as noções de tempo, para ser possível abordar a concepção do risco. As falas dos trabalhadores são postas em diálogo com autores como Dejours, Giddens e Bourdieu. O texto traz elementos descritivos que possibilitam elucidar as relações entre trabalho e masculinidade no setor elétrico a ser um inimigo indissociável do risco.

Indicadores antropométricos de la niñez en situación de calle en Medellín, Colombia

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Camilo Noreña Herrera

2015-02-01

Full Text Available Objetivo: describir los indicadores antropométricos de Índice de Masa Corporal para la Edad (imc/e y Talla para la Edad (t/e de niños, niñas y adolescentes (nna en situación de calle (sc de Medellín, según características sociodemográficas y de consumo de drogas. Metodología: estudio descriptivo de 453 historiales de atención médica y nutricional de nna en sc. Los indicadores antropométricos se categorizaron de acuerdo a los patrones de crecimiento aceptados para Colombia. Se realizó un análisis descriptivo bivariado entre indicadores antropométricos y variables sociodemográficas y de consumo de drogas. Resultados: el 27,8% de los nna tenía talla baja y el 35,3%, riesgo de talla baja. La talla baja fue mayor en hombres (89,7% que en mujeres (10,3% (p < 0,05. Con respecto al imc/e, el 4,2% presentó delgadez, el 14,1% riesgo de delgadez y, un 2,2% presentó exceso de peso. Se encontró diferencia estadísticamente significativa (p < 0,01 entre el imc/e y la edad y entre t/e y el sexo y el nivel de escolaridad. Conclusiones: los nna en sc presentan indicadores antropométricos que evidencian una desfavorable situación nutricional, especialmente para los adolescentes del sexo masculino. Es necesario, además de políticas y programas orientados a la recuperación nutricional de la población, abordar los determinantes estructurales que ocasionan la pobreza, la inequidad y la inseguridad alimentaria en la ciudad para prevenir la situación de vida en calle de NNA.

Simple route of caspase-3 FRET sensor synthesis using “click chemistry”

OpenAIRE

Lišková, M. (Marcela); Křenková, J. (Jana); Klepárník, K. (Karel); Pazdera, P.; Foret, F. (František)

2015-01-01

Programmed cell death or apoptosis is regulated process of cell suicide. The central role in apoptosis play cysteine proteases called caspases. Caspases recognize tetra-peptide sequences Asp-Glu-Val-Asp (DEVD) on their substrates and hydrolyze peptide bonds after aspartic acid residues. Various techniques for the determination of caspase-3 are commercially available e.g. Enzyme Linked Immuno-Sorbent Assay (ELISA), Western blotting or flow cytometric analysis. The products of the cleavage can ...

Perfil antropométrico en adultos del noroeste argentino: comparación con una referencia internacional

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Lomaglio, Delia Beatriz

2015-01-01

Full Text Available Desde una perspectiva bioantropológica las mediciones antropométricas en adultos son exhaustivamente utilizadas en la evaluación morfológica de poblaciones argentinas extintas. La mayoría de los estudios antropométricos en adultos argentinos contemporáneos se limitan a la evaluación de talla, peso e IMC. El objetivo de este trabajo fue describir otras variables antropométricas en adultos del Noroeste argentino (NOA y compararlas con una referencia internacional. Los datos de peso, talla, perímetros (brazo, muslo, pierna, cintura y pliegues (tríceps, subescapular proceden de 881 individuos (526 mujeres; 355 varones sanos de 20-60 años de edad de distintas localidades de Catamarca y Jujuy. Se calcularon estadísticos descriptivos (media y DS por sexo y dos PALABRAS CLAVE adultos; Noroeste Argentino; perímetros; pliegues; antropometría grupos de edad: 20-39 y 40-60 años. Las comparaciones se establecieron con adultos de EEUU de origen mejicano (Centers for Disease Control, CDC 2003-2006 con la prueba t. Se calcularon los percentilos con el método LMS. En ambos sexos y grupos de edad los adultos del NOA presentaron valores significativamente inferiores a los de la referencia en todas las variables consideradas, excepto para pliegues tricipital y subescapular en varones de 40-60 años. No se han encontrado antecedentes antropométricos comparables semejantes para poblaciones argentinas y del NOA. El perfil antropométrico de los adultos del NOA difiere significativamente con respecto a la población de referencia con un origen étnico afín.

Antimicrobial Peptides in 2014

Directory of Open Access Journals (Sweden)

Guangshun Wang

2015-03-01

Full Text Available This article highlights new members, novel mechanisms of action, new functions, and interesting applications of antimicrobial peptides reported in 2014. As of December 2014, over 100 new peptides were registered into the Antimicrobial Peptide Database, increasing the total number of entries to 2493. Unique antimicrobial peptides have been identified from marine bacteria, fungi, and plants. Environmental conditions clearly influence peptide activity or function. Human α-defensin HD-6 is only antimicrobial under reduced conditions. The pH-dependent oligomerization of human cathelicidin LL-37 is linked to double-stranded RNA delivery to endosomes, where the acidic pH triggers the dissociation of the peptide aggregate to release its cargo. Proline-rich peptides, previously known to bind to heat shock proteins, are shown to inhibit protein synthesis. A model antimicrobial peptide is demonstrated to have multiple hits on bacteria, including surface protein delocalization. While cell surface modification to decrease cationic peptide binding is a recognized resistance mechanism for pathogenic bacteria, it is also used as a survival strategy for commensal bacteria. The year 2014 also witnessed continued efforts in exploiting potential applications of antimicrobial peptides. We highlight 3D structure-based design of peptide antimicrobials and vaccines, surface coating, delivery systems, and microbial detection devices involving antimicrobial peptides. The 2014 results also support that combination therapy is preferred over monotherapy in treating biofilms.

Adding an Artificial Tail—Anchor to a Peptide-Based HIV-1 Fusion Inhibitor for Improvement of Its Potency and Resistance Profile

Directory of Open Access Journals (Sweden)

Shan Su

2017-11-01

Full Text Available Peptides derived from the C-terminal heptad repeat (CHR of human immunodeficiency virus type 1 (HIV-1 envelope protein transmembrane subunit gp41, such as T20 (enfuvirtide, can bind to the N-terminal heptad repeat (NHR of gp41 and block six-helix bundle (6-HB formation, thus inhibiting HIV-1 fusion with the target cell. However, clinical application of T20 is limited because of its low potency and genetic barrier to resistance. HP23, the shortest CHR peptide, exhibits better anti-HIV-1 activity than T20, but the HIV-1 strains with E49K mutations in gp41 will become resistant to it. Here, we modified HP23 by extending its C-terminal sequence using six amino acid residues (E6 and adding IDL (Ile-Asp-Leu to the C-terminus of E6, which is expected to bind to the shallow pocket in the gp41 NHR N-terminal region. The newly designed peptide, designated HP23-E6-IDL, was about 2- to 16-fold more potent than HP23 against a broad spectrum of HIV-1 strains and more than 12-fold more effective against HIV-1 mutants resistant to HP23. These findings suggest that addition of an anchor–tail to the C-terminus of a CHR peptide will allow binding with the pocket in the gp41 NHR that may increase the peptide’s antiviral efficacy and its genetic barrier to resistance.

ASPECTOS MORFOMÉTRICOS COMO SUBSÍDIO AO ESTUDO DA CONDUTIVIDADE HIDRÁULICA E SUSCETIBILIDADE EROSIVA DOS SOLOS

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Flávio Alves de Sousa

2012-01-01

Full Text Available Ese artículo es resultante del estúdio que está desarrollándose em la cuenca hidrográfica en la alta cabecera de Rio de los Bois en el distrito de Iporá (GO. El estudio que analiza la relación entre la conductibilidad hidráulica de los suelos, alimentacion del agua subterranea y capacidad de erosion de los suelos, necesita tener informaciones sobre los datos morfométricos, porque éstos ayudan en la comprensión de la dinâmica da agua de la lluvia em la cuenca. Las variables usadas y presentadas en ese artículo son: la altitud máxima y mínima; amplitud altimétrica (Aa; altura média (Am; EI coeficiente del massividad (Cm; el coeficiente orográfico (Co; el índice de rugosidad (Ir; el coeficiente de mantenimiento (Cm; la extensión del percurso superficial (Eps; la densidad de drenage (Dd e declividad média. Destacamos también las características de las rocas y su origen y las características topográficas de la cuenca. La análisis de los factores geomorpologicos foi cumplido com la base em datos planialtimétricos de la cuenca, como declividad, hipsometría y también com el uso de Sistema de Información Geográfica (SIG. Las informaciones geomorfológicas y los datos de SIG ayudaron em la determinación de los parámetros morfométricos.

Connecting peptide (c-peptide) and the duration of diabetes mellitus ...

African Journals Online (AJOL)

Objective: C-peptide is derived from proinsulin and it is secreted in equimolar concentration with insulin. Plasma C-peptide is more stable than insulin and it provides an indirect measure of insulin secretory reserve and beta cell function. To determine relationship between C-peptide and duration of diabetes mellitus, age, ...

Competencia social y status sociométrico escolar en niños y niñas con TDAH

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Daiana Russo, Argentina

2015-07-01

Full Text Available (analítico: Objetivo: Establecer relaciones entre la autopercepción de la competencia social en niños y niñas con TDAH y el status sociométrico escolar. Alcance: Los resultados obtenidos permitirán elaborar estrategias de intervención psicológica como también diseñar abordajes educativos en el aula que fortalezcan la interacción social de estos niños y niñas. Metodología: Estudio descriptivo correlacional con un diseño ex post facto retrospectivo (Montero & León, 2007. La muestra estuvo compuesta por 157 niños y niñas con edades comprendidas entre 8 y 12 años. Conformamos dos grupos, clínico (n=5 y control (n=152, pareados por edad. Administramos el cuestionario Messy (Matson, Rotatori & Helsel, 1983 y el Test sociométrico (Moreno, 1962. Resultados: Los niños y niñas con TDAH son menos asertivos que los niños y niñas del grupo control. La mayoría presenta una posición aislada con respecto a su grupo de pares. Conclusiones: Estos niños y niñas presentan dificultad para establecer relaciones vinculares con sus compañeros y compañeras. No obstante, la autopercepción de sus competencias sociales no coincide en todos los casos con su status sociométrico escolar.

Peptide-Carrier Conjugation

DEFF Research Database (Denmark)

Hansen, Paul Robert

2015-01-01

To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined....

Highly selective enrichment of phosphorylated peptides from peptide mixtures using titanium dioxide microcolumns

DEFF Research Database (Denmark)

Larsen, Martin Røssel; Thingholm, Tine E; Jensen, Ole N

2005-01-01

based on TiO2microcolumns and peptide loading in 2,5-dihydroxybenzoic acid (DHB). The effect of DHB was a very efficient reduction in the binding of nonphosphorylated peptides to TiO2 while retaining its high binding affinity for phosphorylated peptides. Thus, inclusion of DHB dramatically increased...... the selectivity of the enrichment of phosphorylated peptides by TiO2. We demonstrated that this new procedure was more selective for binding phosphorylated peptides than IMAC using MALDI mass spectrometry. In addition, we showed that LC-ESI-MSMS was biased toward monophosphorylated peptides, whereas MALDI MS...... was not. Other substituted aromatic carboxylic acids were also capable of specifically reducing binding of nonphosphorylated peptides, whereas phosphoric acid reduced binding of both phosphorylated and nonphosphorylated peptides. A putative mechanism for this intriguing effect is presented....

Un modelo Macroeconométrico para la Economía Colombiana.

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Javier Arturo Birchenall

2010-05-01

Full Text Available Este documento analiza un modelo macroeconométrico de corto plazo para la economía colombiana, con el fin de evaluar el impacto de procesos de ajuste y estabilización. Se basa en una estructura que reconoce no neutralidades por rigideces de precios y descompone la economía a través de oferta y demanda agregada. El modelo se estima por diversos métodos para el período comprendido entre 1977 y 1998 con una frecuencia trimestral, con el fin de realizar proyecciones para períodos de uno y dos años.

Um estudo do circuito elétrico atmosférico global

OpenAIRE

Turquetti, Gabriela Nunes; Ferreira, Ivan Soares

2016-01-01

O Circuito Elétrico Global é um modelo eletrodinâmico que tenta relacionar os mecanismos de geração de corrente na baixa atmosfera, na ionosfera e na magnetosfera. Com este modelo é possível explicar, por exemplo, os eventos atmosféricos transientes que ocorrem entre o topo da nuvem e a ionosfera logo depois de uma descarga elétrica causada pelos raios durante uma tempestade. O modelo de circuito proposto é baseado em um circuito RC, alimentado por fontes DC e AC, onde os elementos que repres...

Treatment of Experimental Brain Tumors with Trombospondin-1 Derived Peptides: an In Vivo Imaging Study

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A. Bogdanov, Jr.

1999-11-01

Full Text Available Antiangiogenic and antiproliferative effects of synthetic D-reverse peptides derived from the type 1 repeats of thrombospondin (TSP1 [1,2] were studied in rodent C6 glioma and 9L gliosarcomas. To directly measure tumor size and vascular parameters, we employed in vivo magnetic resonance (MR imaging and corroborated results by traditional morphometric tissue analysis. Rats bearing either C6 or 9L tumors were treated with TSP1-derived peptide (D-reverse amKRFKQDGGWSHWSPWSSac, n=13 or a control peptide (D-reverse am KRAKQAGGASHASPASSac, n=12 at 10 mg/kg, administered either intravenously or through subcutaneous miniosmotic pumps starting 10 days after tumor implantation. Eleven days later, the effect of peptide treatment was evaluated. TSP1 peptide-treated 9L tumors (50.7±44.2 mm3, n=7 and C6 tumors (41.3±34.2 mm3, n=6 were significantly smaller than tumors treated with control peptide (9L: 215.7±67.8 mm3, n=6; C6:184.2±105.2 mm3, n=6. In contrast, the in vivo vascular volume fraction, the mean vascular area (determined by microscopy, and the microvascular density of tumors were not significantly different in any of the experimental groups. In cell culture, TSP1, and the amKRFKQDGGWSHWSPWSSac peptide showed antiproliferative effects against C6 with an IC of 45 nM for TSP1. These results indicate that TSP1derived peptides retard brain tumor growth presumably as a result of slower de novo blood vessel formation and synergistic direct antiproliferative effects on tumor cells. We also show that in vivo MR imaging can be used to assess treatment efficacy of novel antiangiogenic drugs non-invasively, which has obvious implications for clinical trials.

A microbially derived tyrosine-sulfated peptide mimics a plant peptide hormone.

Science.gov (United States)

Pruitt, Rory N; Joe, Anna; Zhang, Weiguo; Feng, Wei; Stewart, Valley; Schwessinger, Benjamin; Dinneny, José R; Ronald, Pamela C

2017-07-01

The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated peptide named RaxX, which shares similarity to peptides in the PSY (plant peptide containing sulfated tyrosine) family. We hypothesize that RaxX mimics the growth-stimulating activity of PSY peptides. Root length was measured in Arabidopsis and rice treated with synthetic RaxX peptides. We also used comparative genomic analyses and reactive oxygen species burst assays to evaluate the activity of RaxX and PSY peptides. Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. These findings suggest that RaxX serves as a molecular mimic of PSY peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the peptide. © 2017 UT-Battelle LLC. New Phytologist © 2017 New Phytologist Trust.

Tumor penetrating peptides

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Tambet eTeesalu

2013-08-01

Full Text Available Tumor-homing peptides can be used to deliver drugs into tumors. Phage library screening in live mice has recently identified homing peptides that specifically recognize the endothelium of tumor vessels, extravasate, and penetrate deep into the extravascular tumor tissue. The prototypic peptide of this class, iRGD (CRGDKGPDC, contains the integrin-binding RGD motif. RGD mediates tumor homing through binding to αv integrins, which are selectively expressed on various cells in tumors, including tumor endothelial cells. The tumor-penetrating properties of iRGD are mediated by a second sequence motif, R/KXXR/K. This C-end Rule (or CendR motif is active only when the second basic residue is exposed at the C-terminus of the peptide. Proteolytic processing of iRGD in tumors activates the cryptic CendR motif, which then binds to neuropilin-1 activating an endocytic bulk transport pathway through tumor tissue. Phage screening has also yielded tumor-penetrating peptides that function like iRGD in activating the CendR pathway, but bind to a different primary receptor. Moreover, novel tumor-homing peptides can be constructed from tumor-homing motifs, CendR elements and protease cleavage sites. Pathologies other than tumors can be targeted with tissue-penetrating peptides, and the primary receptor can also be a vascular zip code of a normal tissue. The CendR technology provides a solution to a major problem in tumor therapy, poor penetration of drugs into tumors. The tumor-penetrating peptides are capable of taking a payload deep into tumor tissue in mice, and they also penetrate into human tumors ex vivo. Targeting with these peptides specifically increases the accumulation in tumors of a variety of drugs and contrast agents, such as doxorubicin, antibodies and nanoparticle-based compounds. Remarkably the drug to be targeted does not have to be coupled to the peptide; the bulk transport system activated by the peptide sweeps along any compound that is

Cambios morfométricos cardiacos en adultos hipertensos luego de practicar la necropsia

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Adys Castro Barberena

2017-06-01

Full Text Available Fundamento: la hipertensión arterial se asocia a tasas de morbilidad y mortalidad considerablemente elevadas. Aparecen cambios estructurales del corazón, que le sirven para adaptarse al funcionamiento de un entorno de tensión alta, que conlleva a un desproporcional crecimiento de sus compartimientos. Objetivo: determinar los cambios morfométricos de la víscera cardíaca en pacientes hipertensos luego de practicar la necropsia. Método: se realizó un estudio descriptivo de corte transversal. El universo correspondió a la totalidad de fallecidos mayores de 18 años, con diagnóstico de hipertensión arterial, luego de practicar la necropsia en el periodo de enero 2014 a julio 2015 en el Hospital General Universitario Dr. Gustavo Aldereguía Lima de Cienfuegos. Se consideraron las variables: sexo, edad, índice de masa corporal, tiempo de evolución de la hipertensión arterial, peso del corazón, espesor del ventrículo izquierdo y derecho, espesor del atrio izquierdo y diámetro de las arterias coronarias derecha e izquierda. La información recopilada se procesó en forma computarizada por medio del programa SPSS versión 11,5, para lo cual se realizó una base de datos. Los resultados se presentan en frecuencias absolutas y relativas, por medio de tablas y gráficos estadísticos, empleando medias, medianas y porcentajes para su desarrollo. Resultados: los cambios morfométricos cardiacos fueron mayores en los hipertensos a los que se les realizó la necropsia, del sexo masculino, mayores de 50 años y con más de diez años de evolución de la enfermedad, predominando en el ventrículo izquierdo, estenosis en ambas coronarias y un aumento del peso del corazón. Conclusiones: existe relación entre los cambios morfométricos cardiacos de los pacientes adultos hipertensos fallecidos luego de practicar la necropsia, con el sexo, la edad, el índice de masa corporal y tiempo de evolución de la hipertensión arterial.

Peptide Nucleic Acids

DEFF Research Database (Denmark)

2003-01-01

A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

Peptide Nucleic Acids

DEFF Research Database (Denmark)

1998-01-01

A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

PeptideAtlas

Data.gov (United States)

U.S. Department of Health & Human Services — PeptideAtlas is a multi-organism, publicly accessible compendium of peptides identified in a large set of tandem mass spectrometry proteomics experiments. Mass...

Synthetic peptide vaccines: palmitoylation of peptide antigens by a thioester bond increases immunogenicity

DEFF Research Database (Denmark)

Beekman, N.J.C.M.; Schaaper, W.M.M.; Tesser, G.I.

1997-01-01

Synthetic peptides have frequently been used to immunize animals. However, peptides less than about 20 to 30 amino acids long are poor immunogens. In general, to increase its immunogenicity, the presentation of the peptide should be improved, and molecular weight needs to be increased. Many...... or an amide bond. It was found that these S-palmitoylated peptides were much more immunogenic than N-palmitoylated peptides and at least similar to KLH-conjugated peptides with respect to appearance and magnitude of induced antibodies (canine parvovirus) or immunocastration effect (gonadotropin...

Substitutions of PrP N-terminal histidine residues modulate scrapie disease pathogenesis and incubation time in transgenic mice.

Science.gov (United States)

Eigenbrod, Sabina; Frick, Petra; Bertsch, Uwe; Mitteregger-Kretzschmar, Gerda; Mielke, Janina; Maringer, Marko; Piening, Niklas; Hepp, Alexander; Daude, Nathalie; Windl, Otto; Levin, Johannes; Giese, Armin; Sakthivelu, Vignesh; Tatzelt, Jörg; Kretzschmar, Hans; Westaway, David

2017-01-01

Prion diseases have been linked to impaired copper homeostasis and copper induced-oxidative damage to the brain. Divalent metal ions, such as Cu2+ and Zn2+, bind to cellular prion protein (PrPC) at octapeptide repeat (OR) and non-OR sites within the N-terminal half of the protein but information on the impact of such binding on conversion to the misfolded isoform often derives from studies using either OR and non-OR peptides or bacterially-expressed recombinant PrP. Here we created new transgenic mouse lines expressing PrP with disrupted copper binding sites within all four histidine-containing OR's (sites 1-4, H60G, H68G, H76G, H84G, "TetraH>G" allele) or at site 5 (composed of residues His-95 and His-110; "H95G" allele) and monitored the formation of misfolded PrP in vivo. Novel transgenic mice expressing PrP(TetraH>G) at levels comparable to wild-type (wt) controls were susceptible to mouse-adapted scrapie strain RML but showed significantly prolonged incubation times. In contrast, amino acid replacement at residue 95 accelerated disease progression in corresponding PrP(H95G) mice. Neuropathological lesions in terminally ill transgenic mice were similar to scrapie-infected wt controls, but less severe. The pattern of PrPSc deposition, however, was not synaptic as seen in wt animals, but instead dense globular plaque-like accumulations of PrPSc in TgPrP(TetraH>G) mice and diffuse PrPSc deposition in (TgPrP(H95G) mice), were observed throughout all brain sections. We conclude that OR and site 5 histidine substitutions have divergent phenotypic impacts and that cis interactions between the OR region and the site 5 region modulate pathogenic outcomes by affecting the PrP globular domain.

DESARROLLO Y VALIDACIÓN DE UN MÉTODO ESPECTROFOTOMÉTRICO/COLORIMÉTRICO PARA LA DETERMINACIÓN DE CROMO (III EN LICORES RESIDUALES DE PIQUELADO-CURTIDO

Directory of Open Access Journals (Sweden)

Ramiro Escalera Vásquez

2007-01-01

Full Text Available Dos métodos no destructivos fueron desarrollados y validados para la determinación de concentraciones de sales de cromo en licores residuales de curtido que se producen en la fabricación de cueros: Un método espectrofotométrico y un método colorimétrico derivado. Los dos métodos se basan en el análisis de espectros de absorbancia-longitud de onda generados por soluciones patrón que fueron preparadas con los mismos reactivos químicos comerciales utilizados por una curtiembre local, en el intervalo de longitud de onda de 190-800 nm (UV-visible. Ambos métodos satisfacen los criterios fundamentales de validación: proporcionalidad (buena linealidad y buena sensibilidad dentro del intervalo de concentraciones de sales de cromo que se observa en los licores residuales de curtido; precisión (buena repetibilidad/reproducibilidad; exactitud (sin diferencias estadísticas respecto a métodos oficiales y selectividad (buena especificidad para la sal de cromo. Estos métodos son prácticos por su simplicidad, bajo costo y rapidez. Requieren equipos de bajo costo (un espectrofotómetro de rango visible o un colorímetro fabricado manualmente, usan los mismos reactivos químicos que se aplican en procesos de curtido corriente y no requieren de condiciones de seguridad especiales ni personal especializado. Los métodos pueden ser utilizados para el control de reciclado directo de licores de curtido-piquelado, facilitando de esta manera la adopción de esta técnica de Producción Más Limpia por parte de los fabricantes de cueros, especialmente curtiembres de escala pequeña y mediana.

Complexes between lanthanide (III) and yttrium (III) picrates and tetra methylene sulfoxide as ligand

International Nuclear Information System (INIS)

Silva, M.A.A. da.

1991-01-01

The preparation and characterization of addition compounds between lanthanide (III) and yttrium (III) picrates and tetra methylene sulfoxide as ligand were described. The adducts were prepared in the molar relation 1 (salt): 3(ligand) in ethanol. They are microcrystalline with more intense color than those of their respective hydrated salts. At room temperature conditions they are non hygroscopic and do not present perceptible alterations. They became slightly opalescent, when heated between 363 and 423 K. At higher temperatures under several heating ratios, the behavior shown is the same: melting between 439 and 472 K. The characterization of the compounds was made by elemental analysis, electrolytic conductance measurements, X-ray powder patterns, infrared spectroscopy, visible electronic absorption and emission spectra of the neodymium (III) and europium (III), respectively. (author). 116 refs., 17 tabs., 11 figs

Penerapan Perencanaan Pajak Penghasilan pada Fa Trico Paint Factory

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Stefanus Ariyanto

2011-05-01

Full Text Available The most important parts of government income comes from taxes, especially income taxes. The different point of view arises between government and tax payer. While the government try to increase the tax income, the taxpayers always intend to minimize their tax burden by implementing tax management/plannning. This paper is a case study in FA Trico Paint Factory (FA TPF that try to reperforming company’s income tax return preparation with the main purpose to minimize company tax burden, while it is still comply with tax regulations in Indonesia. This approach could be an alternative for the company to restate it’s annual income tax return, to avoic fines and charges for not comply with the regulations, and minimize it’s income tax expense by approximately 10% per year. 

Diversity-oriented peptide stapling

DEFF Research Database (Denmark)

Tran, Thu Phuong; Larsen, Christian Ørnbøl; Røndbjerg, Tobias

2017-01-01

as a powerful method for peptide stapling. However, to date CuAAC stapling has not provided a simple method for obtaining peptides that are easily diversified further. In the present study, we report a new diversity-oriented peptide stapling (DOPS) methodology based on CuAAC chemistry. Stapling of peptides...

CXCL10 Controls Inflammatory Pain via Opioid Peptide-Containing Macrophages in Electroacupuncture

Science.gov (United States)

Wang, Ying; Gehringer, Rebekka; Mousa, Shaaban A.; Hackel, Dagmar; Brack, Alexander; Rittner, Heike L.

2014-01-01

Acupuncture is widely used for pain treatment in patients with osteoarthritis or low back pain, but molecular mechanisms remain largely enigmatic. In the early phase of inflammation neutrophilic chemokines direct opioid-containing neutrophils in the inflamed tissue and stimulate opioid peptide release and antinociception. In this study the molecular pathway and neuroimmune connections in complete Freund's adjuvant (CFA)-induced hind paw inflammation and electroacupuncture for peripheral pain control were analyzed. Free moving Wistar rats with hind paw inflammation were treated twice with electroacupuncture at GB30 (Huan Tiao - gall bladder meridian) (day 0 and 1) and analyzed for mechanical and thermal nociceptive thresholds. The cytokine profiles as well as the expression of opioid peptides were quantified in the inflamed paw. Electroacupuncture elicited long-term antinociception blocked by local injection of anti-opioid peptide antibodies (beta-endorphin, met-enkephalin, dynorphin A). The treatment altered the cytokine profile towards an anti-inflammatory pattern but augmented interferon (IFN)-gamma and the chemokine CXCL10 (IP-10: interferon gamma-inducible protein) protein and mRNA expression with concomitant increased numbers of opioid peptide-containing CXCR3+ macrophages. In rats with CFA hind paw inflammation without acupuncture repeated injection of CXCL10 triggered opioid-mediated antinociception and increase opioid-containing macrophages. Conversely, neutralization of CXCL10 time-dependently decreased electroacupuncture-induced antinociception and the number of infiltrating opioid peptide-expressing CXCR3+ macrophages. In summary, we describe a novel function of the chemokine CXCL10 - as a regulator for an increase of opioid-containing macrophages and antinociceptive mediator in inflammatory pain and as a key chemokine regulated by electroacupuncture. PMID:24732949

Effect of a Fusion Peptide by Covalent Conjugation of a Mitochondrial Cell-Penetrating Peptide and a Glutathione Analog Peptide

Directory of Open Access Journals (Sweden)

Carmine Pasquale Cerrato

2017-06-01

Full Text Available Previously, we designed and synthesized a library of mitochondrial antioxidative cell-penetrating peptides (mtCPPs superior to the parent peptide, SS31, to protect mitochondria from oxidative damage. A library of antioxidative glutathione analogs called glutathione peptides (UPFs, exceptional in hydroxyl radical elimination compared with glutathione, were also designed and synthesized. Here, a follow-up study is described, investigating the effects of the most promising members from both libraries on reactive oxidative species scavenging ability. None of the peptides influenced cell viability at the concentrations used. Fluorescence microscopy studies showed that the fluorescein-mtCPP1-UPF25 (mtgCPP internalized into cells, and spectrofluorometric analysis determined the presence and extent of peptide into different cell compartments. mtgCPP has superior antioxidative activity compared with mtCPP1 and UPF25 against H2O2 insult, preventing ROS formation by 2- and 3-fold, respectively. Moreover, we neither observed effects on mitochondrial membrane potential nor production of ATP. These data indicate that mtgCPP is targeting mitochondria, protecting them from oxidative damage, while also being present in the cytosol. Our hypothesis is based on a synergistic effect resulting from the fused peptide. The mitochondrial peptide segment is targeting mitochondria, whereas the glutathione analog peptide segment is active in the cytosol, resulting in increased scavenging ability.

Peptide-membrane interactions of arginine-tryptophan peptides probed using quartz crystal microbalance with dissipation monitoring.

KAUST Repository

Rydberg, Hanna A

2014-04-18

Membrane-active peptides include peptides that can cross cellular membranes and deliver macromolecular cargo as well as peptides that inhibit bacterial growth. Some of these peptides can act as both transporters and antibacterial agents. It is desirable to combine the knowledge from these two different fields of membrane-active peptides into design of new peptides with tailored actions, as transporters of cargo or as antibacterial substances, targeting specific membranes. We have previously shown that the position of the amino acid tryptophan in the peptide sequence of three arginine-tryptophan peptides affects their uptake and intracellular localization in live mammalian cells, as well as their ability to inhibit bacterial growth. Here, we use quartz crystal microbalance with dissipation monitoring to assess the induced changes caused by binding of the three peptides to supported model membranes composed of POPC, POPC/POPG, POPC/POPG/cholesterol or POPC/lactosyl PE. Our results indicate that the tryptophan position in the peptide sequence affects the way these peptides interact with the different model membranes and that the presence of cholesterol in particular seems to affect the membrane interaction of the peptide with an even distribution of tryptophans in the peptide sequence. These results give mechanistic insight into the function of these peptides and may aid in the design of membrane-active peptides with specified cellular targets and actions.

Peptide-membrane interactions of arginine-tryptophan peptides probed using quartz crystal microbalance with dissipation monitoring.

KAUST Repository

Rydberg, Hanna A; Kunze, Angelika; Carlsson, Nils; Altgä rde, Noomi; Svedhem, Sofia; Nordé n, Bengt

2014-01-01

Membrane-active peptides include peptides that can cross cellular membranes and deliver macromolecular cargo as well as peptides that inhibit bacterial growth. Some of these peptides can act as both transporters and antibacterial agents. It is desirable to combine the knowledge from these two different fields of membrane-active peptides into design of new peptides with tailored actions, as transporters of cargo or as antibacterial substances, targeting specific membranes. We have previously shown that the position of the amino acid tryptophan in the peptide sequence of three arginine-tryptophan peptides affects their uptake and intracellular localization in live mammalian cells, as well as their ability to inhibit bacterial growth. Here, we use quartz crystal microbalance with dissipation monitoring to assess the induced changes caused by binding of the three peptides to supported model membranes composed of POPC, POPC/POPG, POPC/POPG/cholesterol or POPC/lactosyl PE. Our results indicate that the tryptophan position in the peptide sequence affects the way these peptides interact with the different model membranes and that the presence of cholesterol in particular seems to affect the membrane interaction of the peptide with an even distribution of tryptophans in the peptide sequence. These results give mechanistic insight into the function of these peptides and may aid in the design of membrane-active peptides with specified cellular targets and actions.

ALGUNAS PROPIEDADES COMBINATORIAS DE LOS POLINOMIOS SIMÉTRICOS Y CÓMPUTO DE POLINOMIOS DE SCHUR OBLICUOS

Directory of Open Access Journals (Sweden)

Fernando Novoa

2005-06-01

Full Text Available Presentamos algunas rutinas de un programa para el sistema computacional CoCoA, las cuales realizan el cómputo de familias de polinomios de simétricos, entre ellas los polinomios de Schur. Con estas rutinas se pueden comprobar propiedades combinatorias que relacionan tablas de Young y polinomios skew de Schur.

El laboratorio en la investigación cerámica. Análisis dilatométrico

Directory of Open Access Journals (Sweden)

Fernando Arredondo

2017-06-01

Full Text Available Se estudian las variaciones dimensionales que experimenta una arcilla durante su cocción, así como los métodos actuales para determinarlas. Se describe el dilatómetro, usado en el laboratorio de cerámica del I. T. C. G. para realizar el análisis dilatométrico.

Automated solid-phase peptide synthesis to obtain therapeutic peptides

Directory of Open Access Journals (Sweden)

Veronika Mäde

2014-05-01

Full Text Available The great versatility and the inherent high affinities of peptides for their respective targets have led to tremendous progress for therapeutic applications in the last years. In order to increase the drugability of these frequently unstable and rapidly cleared molecules, chemical modifications are of great interest. Automated solid-phase peptide synthesis (SPPS offers a suitable technology to produce chemically engineered peptides. This review concentrates on the application of SPPS by Fmoc/t-Bu protecting-group strategy, which is most commonly used. Critical issues and suggestions for the synthesis are covered. The development of automated methods from conventional to essentially improved microwave-assisted instruments is discussed. In order to improve pharmacokinetic properties of peptides, lipidation and PEGylation are described as covalent conjugation methods, which can be applied by a combination of automated and manual synthesis approaches. The synthesis and application of SPPS is described for neuropeptide Y receptor analogs as an example for bioactive hormones. The applied strategies represent innovative and potent methods for the development of novel peptide drug candidates that can be manufactured with optimized automated synthesis technologies.

Características de las infecciones nosocomiales en el servicio de cuidados intensivos pediátricos del Hospital Vicente Corral Moscoso, Cuenca 2014 -2015

OpenAIRE

Salcedo González, Rosa Karina

2016-01-01

Objetivo: Determinar las características de las infecciones nosocomiales en el servicio de Cuidados Intensivos Pediátricos del Hospital Vicente Corral Moscoso durante el año 2014 al 2015. Materiales y métodos: estudio descriptivo llevado a cabo en 32 pacientes diagnosticados de infección nosocomial en la Unidad de Cuidados Intensivos Pediátricos del Hospital Vicente Corral Moscoso; los datos fueron recogidos en un formulario; se tabularon en el programa SPSS versión 15 y para el análisis ...

Production of peptide antisera specific for mouse and rat proinsulin C-peptide 2

DEFF Research Database (Denmark)

Blume, N; Madsen, O D; Kofod, Hans

1990-01-01

for antibody binding to the immunizing antigen. Antisera to C-peptide 2, stained islet beta-cells on mouse and rat, but not monkey pancreas sections in immunocytochemical analysis. Preabsorption to the synthetic C-peptide 2, but not the synthetic mouse and rat C-peptide 1 abolished staining. In conclusion we......Mice and rats have two functional non-allelic insulin genes. By using a synthetic peptide representing a common sequence in mouse and rat C-peptide 2 as antigen, we have produced rabbit antisera specific for an epitope which is not present in mouse or rat C-peptide 1. Long-term immunization did...... not seem to increase the end point titre as tested in direct ELISA. The specificity of the antiserum was determined by competitive ELISA and histochemistry on pancreas sections. Only the synthetic C-peptide 2, but not the homologous synthetic C-peptide 1 from mouse and rat competed efficiently in ELISA...

Therapeutic peptides for cancer therapy. Part I - peptide inhibitors of signal transduction cascades.

Science.gov (United States)

Bidwell, Gene L; Raucher, Drazen

2009-10-01

Therapeutic peptides have great potential as anticancer agents owing to their ease of rational design and target specificity. However, their utility in vivo is limited by low stability and poor tumor penetration. The authors review the development of peptide inhibitors with potential for cancer therapy. Peptides that inhibit signal transduction cascades are discussed. The authors searched Medline for articles concerning the development of therapeutic peptides and their delivery. Given our current knowledge of protein sequences, structures and interaction interfaces, therapeutic peptides that inhibit interactions of interest are easily designed. These peptides are advantageous because they are highly specific for the interaction of interest, and they are much more easily developed than small molecule inhibitors of the same interactions. The main hurdle to application of peptides for cancer therapy is their poor pharmacokinetic and biodistribution parameters. Therefore, successful development of peptide delivery vectors could potentially make possible the use of this new and very promising class of anticancer agents.

Ação do ácido cítrico aplicado em substrato de mudas de café adubado com fósforo

OpenAIRE

Schiavon, Nykolas Carvalho

2015-01-01

A adição de ácido cítrico ao substrato pode influenciar a disponibilidade de fósforo para as plantas de café e possibilitar melhor crescimento e nutrição. Além disso, o crescimento e a nutrição possivelmente sofrerão influencia da cultivar e do parcelamento de dose do ácido cítrico. Por isso, objetivou-se avaliar o crescimento e acúmulo de nutrientes por mudas de café (Coffea arabicaL.) de três cultivares: Catuaí Vermelho IAC 99, Mundo Novo IAC 379- 19 e Oeiras MG 6851, em subs...

Purification and use of E. coli peptide deformylase for peptide deprotection in chemoenzymatic peptide synthesis

NARCIS (Netherlands)

Di Toma, Claudia; Sonke, Theo; Quaedflieg, Peter J.; Janssen, Dick B.

Peptide deformylases (PDFs) catalyze the removal of the formyl group from the N-terminal methionine residue in nascent polypeptide chains in prokaryotes. Its deformylation activity makes PDF an attractive candidate for the biocatalytic deprotection of formylated peptides that are used in

The polymorphic integumentary mucin B.1 from Xenopus laevis contains the short consensus repeat.

Science.gov (United States)

Probst, J C; Hauser, F; Joba, W; Hoffmann, W

1992-03-25

The frog integumentary mucin B.1 (FIM-B.1), discovered by molecular cloning, contains a cysteine-rich C-terminal domain which is homologous with von Willebrand factor. With the help of the polymerase chain reaction, we now characterize a contiguous region 5' to the von Willebrand factor domain containing the short consensus repeat typical of many proteins from the complement system. Multiple transcripts have been cloned, which originate from a single animal and differ by a variable number of tandem repeats (rep-33 sequences). These different transcripts probably originate solely from two genes and are generated presumably by alternative splicing of an huge array of functional cassettes. This model is supported by analysis of genomic FIM-B.1 sequences from Xenopus laevis. Here, rep-33 sequences are arranged in an interrupted array of individual units. Additionally, results of Southern analysis revealed genetic polymorphism between different animals which is predicted to be within the tandem repeats. A first investigation of the predicted mucins with the help of a specific antibody against a synthetic peptide determined the molecular mass of FIM-B.1 to greater than 200 kDa. Here again, genetic polymorphism between different animals is detected.

Antioxidant activity of yoghurt peptides: Part 2 – Characterisationof peptide fractions

DEFF Research Database (Denmark)

Farvin, Sabeena; Baron, Caroline; Nielsen, Nina Skall

2010-01-01

the peptides identified contained at least one proline residue. Some of the identified peptides included the hydrophobic amino acid residues Val or Leu at the N-terminus and Pro, His or Tyr in the amino acid sequence, which is characteristic of antioxidant peptides. In addition, the yoghurt contained...

Ligand-regulated peptide aptamers.

Science.gov (United States)

Miller, Russell A

2009-01-01

The peptide aptamer approach employs high-throughput selection to identify members of a randomized peptide library displayed from a scaffold protein by virtue of their interaction with a target molecule. Extending this approach, we have developed a peptide aptamer scaffold protein that can impart small-molecule control over the aptamer-target interaction. This ligand-regulated peptide (LiRP) scaffold, consisting of the protein domains FKBP12, FRB, and GST, binds to the cell-permeable small-molecule rapamycin and the binding of this molecule can prevent the interaction of the randomizable linker region connecting FKBP12 with FRB. Here we present a detailed protocol for the creation of a peptide aptamer plasmid library, selection of peptide aptamers using the LiRP scaffold in a yeast two-hybrid system, and the screening of those peptide aptamers for a ligand-regulated interaction.

Determination of bovine lactoferrin in dairy products by ultra-high performance liquid chromatography–tandem mass spectrometry based on tryptic signature peptides employing an isotope-labeled winged peptide as internal standard

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jingshun [Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051 (China); Lai, Shiyun [Beingmate Research Institute, Beingmate Baby and Child Food Co., Ltd., Hangzhou 310007 (China); Cai, Zengxuan [Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051 (China); Chen, Qi [Beingmate Research Institute, Beingmate Baby and Child Food Co., Ltd., Hangzhou 310007 (China); Huang, Baifen [Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051 (China); Ren, Yiping, E-mail: renyiping@263.net [Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051 (China)

2014-06-01

Highlights: • A UHPLC–MS/MS method for quantification of bovine lactoferrin was developed. • Tryptic fragment LRPVAAEIYGTK was chosen as signature peptide of bovine lactoferrin. • A winged peptide containing isotopically-labeled signature peptide was designed as internal standard. • The method for determining lactoferrin does not discriminate between the different forms of lactoferrin. • Meet the growing demand to quantify bovine lactoferrin in different dairy products. Abstract: A new and sensitive determination method was developed for bovine lactoferrin in dairy products including infant formulas based on the signature peptide by ultra high-performance liquid chromatography and triple-quadrupole tandem mass spectrometry under the multiple reaction monitoring mode. The simple pretreatment procedures included the addition of a winged peptide containing the isotope-labeled signature peptide as internal standard, followed by an enzymatic digestion with trypsin. The signature peptide was chosen and identified from the tryptic hydrolyzates of bovine lactoferrin by ultra high-performance liquid chromatography and quadrupole-time-of-flight tandem mass spectrometry based on sequence database search. Analytes were separated on an ACQUITY UPLC BEH 300 C18 column and monitored by MS/MS in seven minutes. Quantitative result bias due to matrix effect and tryptic efficiency was corrected through the use of synthetic isotope-labeled standards. The limit of detection and limit of quantification were 0.3 mg/100 g and 1.0 mg/100 g, respectively. Bovine lactoferrin within the concentration range of 10–1000 nmol L⁻¹ showed a strong linear relationship with a linear correlation coefficient (r) of >0.998. The intra- and inter-day precision of the method were RSD < 6.5% and RSD < 7.1%, respectively. Excellent repeatability (RSD < 6.4%) substantially supported the application of this method for the determination of bovine lactoferrin in dairy samples. The present method

Determination of bovine lactoferrin in dairy products by ultra-high performance liquid chromatography–tandem mass spectrometry based on tryptic signature peptides employing an isotope-labeled winged peptide as internal standard

International Nuclear Information System (INIS)

Zhang, Jingshun; Lai, Shiyun; Cai, Zengxuan; Chen, Qi; Huang, Baifen; Ren, Yiping

2014-01-01

Highlights: • A UHPLC–MS/MS method for quantification of bovine lactoferrin was developed. • Tryptic fragment LRPVAAEIYGTK was chosen as signature peptide of bovine lactoferrin. • A winged peptide containing isotopically-labeled signature peptide was designed as internal standard. • The method for determining lactoferrin does not discriminate between the different forms of lactoferrin. • Meet the growing demand to quantify bovine lactoferrin in different dairy products. - Abstract: A new and sensitive determination method was developed for bovine lactoferrin in dairy products including infant formulas based on the signature peptide by ultra high-performance liquid chromatography and triple-quadrupole tandem mass spectrometry under the multiple reaction monitoring mode. The simple pretreatment procedures included the addition of a winged peptide containing the isotope-labeled signature peptide as internal standard, followed by an enzymatic digestion with trypsin. The signature peptide was chosen and identified from the tryptic hydrolyzates of bovine lactoferrin by ultra high-performance liquid chromatography and quadrupole-time-of-flight tandem mass spectrometry based on sequence database search. Analytes were separated on an ACQUITY UPLC BEH 300 C18 column and monitored by MS/MS in seven minutes. Quantitative result bias due to matrix effect and tryptic efficiency was corrected through the use of synthetic isotope-labeled standards. The limit of detection and limit of quantification were 0.3 mg/100 g and 1.0 mg/100 g, respectively. Bovine lactoferrin within the concentration range of 10–1000 nmol L −1 showed a strong linear relationship with a linear correlation coefficient (r) of >0.998. The intra- and inter-day precision of the method were RSD < 6.5% and RSD < 7.1%, respectively. Excellent repeatability (RSD < 6.4%) substantially supported the application of this method for the determination of bovine lactoferrin in dairy samples. The present

Study of the pO2-sensitivity of the dendrimeric and free forms of Pd-meso-tetra(4-carboxyphenyl)porphyrin, incorporated or not in chitosan-based nanoparticles.

Science.gov (United States)

Nowak-Sliwinska, Patrycja; Käuper, Peter; van den Bergh, Hubert; Wagnières, Georges

2011-01-01

The concentration of oxygen and its rate of consumption are important factors in certain medical treatments, such as radiotherapy and photodynamic therapy (PDT). Measuring the tissue concentration of oxygen or its partial pressure (pO2) can be achieved by taking advantage of the oxygen-dependent luminescence lifetime of certain molecules, including metallo-porphyrin derivatives, due to the oxygen-dependent quenching of their triplet state. Unfortunately, most of these porphyrin derivatives are phototoxic due to the O(2)1delta produced in the pO2 measurement procedure. The aim of this work was to characterize new nanoparticle oxygen sensors, where the palladium-porhyrin molecule (Pd-meso-tetra(4-carboxyphenyl)porphyrin) or its dendrimer form, is incorporated into an oxygen permeable matrix of chitosan-based colloidal particles. It was hypothesized that the reactive O(2)1delta produced during the pO2 measurement would react inside the particle thus reducing its toxicity for the surrounding tissue, whereas the 3sigma ground state of O2, that is to be measured, would diffuse freely in the peptide. We observed that the incorporation of the porphyrin in the nanoparticles resulted in a reduction of the phosphorescence lifetime sensitivity to pO2 by about one order of magnitude. Our studies of these new sensors indicate that the oxygen concentration can be measured in aqueous solutions with a precision of +/- 20% for oxygen concentrations ranging between 0% and 25%.

A distributive peptide cyclase processes multiple microviridin core peptides within a single polypeptide substrate.

Science.gov (United States)

Zhang, Yi; Li, Kunhua; Yang, Guang; McBride, Joshua L; Bruner, Steven D; Ding, Yousong

2018-05-03

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are an important family of natural products. Their biosynthesis follows a common scheme in which the leader peptide of a precursor peptide guides the modifications of a single core peptide. Here we describe biochemical studies of the processing of multiple core peptides within a precursor peptide, rare in RiPP biosynthesis. In a cyanobacterial microviridin pathway, an ATP-grasp ligase, AMdnC, installs up to two macrolactones on each of the three core peptides within AMdnA. The enzyme catalysis occurs in a distributive fashion and follows an unstrict N-to-C overall directionality, but a strict order in macrolactonizing each core peptide. Furthermore, AMdnC is catalytically versatile to process unnatural substrates carrying one to four core peptides, and kinetic studies provide insights into its catalytic properties. Collectively, our results reveal a distinct biosynthetic logic of RiPPs, opening up the possibility of modular production via synthetic biology approaches.

Bioactive surface modifications on inner walls of poly-tetra-fluoro-ethylene tubes using dielectric barrier discharge

Energy Technology Data Exchange (ETDEWEB)

Cho, Yong Ki [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Heat Treatment and Surface Engineering R and D Group, Korea Institute of Industrial Technology, Incheon 406-840 (Korea, Republic of); Park, Daewon; Kim, Hoonbae [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Hyerim; Park, Heonyong [Department of Molecular Biology, Dankook University, Yongin 448-701 (Korea, Republic of); Kim, Hong Ja [Department of Internal Medicine, Dankook University, Cheonan 330-714 (Korea, Republic of); Jung, Donggeun, E-mail: djung@skku.ac.kr [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2014-03-01

Graphical abstract: - Highlights: • The surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts. • Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment using micro plasma discharge. - Abstract: Bioactive surface modification can be used in a variety of medical polymeric materials in the fields of biochips and biosensors, artificial membranes, and vascular grafts. In this study, the surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts, which are made of biocompatible material for the human body in the medical field. Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment on the PFTE surface using micro plasma discharge. Micro plasma was generated by a medium-frequency alternating current high-voltage generator. The preliminary modification of PTFE was conducted by a plasma of hydrogen and argon gases. The hydrocarbon thin film was deposited on modified PTFE with a mixture of acetylene and argon gases. The reactive plasma treatment using oxygen plasma was done to give biocompatible functionality to the inner wall surface. The hydrophobic surface of bare PTFE is made hydrophilic by the reactive plasma treatment due to the formation of carbonyl groups on the surface. The reactive treatment could lead to improved attachment of smooth muscle cells (SMCs) on the modified PTFE tubing. Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurement were used for the analysis of the surface modification. The SMC-attached PTFE tube developed will be applicable to in vitro human vasculature

Bioactive surface modifications on inner walls of poly-tetra-fluoro-ethylene tubes using dielectric barrier discharge

International Nuclear Information System (INIS)

Cho, Yong Ki; Park, Daewon; Kim, Hoonbae; Lee, Hyerim; Park, Heonyong; Kim, Hong Ja; Jung, Donggeun

2014-01-01

Graphical abstract: - Highlights: • The surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts. • Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment using micro plasma discharge. - Abstract: Bioactive surface modification can be used in a variety of medical polymeric materials in the fields of biochips and biosensors, artificial membranes, and vascular grafts. In this study, the surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts, which are made of biocompatible material for the human body in the medical field. Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment on the PFTE surface using micro plasma discharge. Micro plasma was generated by a medium-frequency alternating current high-voltage generator. The preliminary modification of PTFE was conducted by a plasma of hydrogen and argon gases. The hydrocarbon thin film was deposited on modified PTFE with a mixture of acetylene and argon gases. The reactive plasma treatment using oxygen plasma was done to give biocompatible functionality to the inner wall surface. The hydrophobic surface of bare PTFE is made hydrophilic by the reactive plasma treatment due to the formation of carbonyl groups on the surface. The reactive treatment could lead to improved attachment of smooth muscle cells (SMCs) on the modified PTFE tubing. Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurement were used for the analysis of the surface modification. The SMC-attached PTFE tube developed will be applicable to in vitro human vasculature

Superior Antifouling Performance of a Zwitterionic Peptide Compared to an Amphiphilic, Non-Ionic Peptide.

Science.gov (United States)

Ye, Huijun; Wang, Libing; Huang, Renliang; Su, Rongxin; Liu, Boshi; Qi, Wei; He, Zhimin

2015-10-14

The aim of this study was to explore the influence of amphiphilic and zwitterionic structures on the resistance of protein adsorption to peptide self-assembled monolayers (SAMs) and gain insight into the associated antifouling mechanism. Two kinds of cysteine-terminated heptapeptides were studied. One peptide had alternating hydrophobic and hydrophilic residues with an amphiphilic sequence of CYSYSYS. The other peptide (CRERERE) was zwitterionic. Both peptides were covalently attached onto gold substrates via gold-thiol bond formation. Surface plasmon resonance analysis results showed that both peptide SAMs had ultralow or low protein adsorption amounts of 1.97-11.78 ng/cm2 in the presence of single proteins. The zwitterionic peptide showed relatively higher antifouling ability with single proteins and natural complex protein media. We performed molecular dynamics simulations to understand their respective antifouling behaviors. The results indicated that strong surface hydration of peptide SAMs contributes to fouling resistance by impeding interactions with proteins. Compared to the CYSYSYS peptide, more water molecules were predicted to form hydrogen-bonding interactions with the zwitterionic CRERERE peptide, which is in agreement with the antifouling test results. These findings reveal a clear relation between peptide structures and resistance to protein adsorption, facilitating the development of novel peptide-containing antifouling materials.

Antimicrobial Peptides in Reptiles

Science.gov (United States)

van Hoek, Monique L.

2014-01-01

Reptiles are among the oldest known amniotes and are highly diverse in their morphology and ecological niches. These animals have an evolutionarily ancient innate-immune system that is of great interest to scientists trying to identify new and useful antimicrobial peptides. Significant work in the last decade in the fields of biochemistry, proteomics and genomics has begun to reveal the complexity of reptilian antimicrobial peptides. Here, the current knowledge about antimicrobial peptides in reptiles is reviewed, with specific examples in each of the four orders: Testudines (turtles and tortosises), Sphenodontia (tuataras), Squamata (snakes and lizards), and Crocodilia (crocodilans). Examples are presented of the major classes of antimicrobial peptides expressed by reptiles including defensins, cathelicidins, liver-expressed peptides (hepcidin and LEAP-2), lysozyme, crotamine, and others. Some of these peptides have been identified and tested for their antibacterial or antiviral activity; others are only predicted as possible genes from genomic sequencing. Bioinformatic analysis of the reptile genomes is presented, revealing many predicted candidate antimicrobial peptides genes across this diverse class. The study of how these ancient creatures use antimicrobial peptides within their innate immune systems may reveal new understandings of our mammalian innate immune system and may also provide new and powerful antimicrobial peptides as scaffolds for potential therapeutic development. PMID:24918867

Radio peptide imaging and therapy

International Nuclear Information System (INIS)

Buscombe, Jonh

1997-01-01

Full text. The concept of the magic bullet retains its attraction to us. If only we could take a drug or radioisotope and inject this intravenously and then will attach to the target cancer. This may allow imaging if labelled with a radio pharmaceutical or possibly even effective therapy. Initially work was started using antibodies of mouse origin. These have shown some utility in targeting tumors but there are problems in that these are essentially non-human proteins, often derived from mice. This leads to the formation of antibodies against that antibody so that repeat administrations lead to reduced efficacy and possibly may carry a risk anaphylaxis for the patient. Two different methods have evolved to deal with this situation. Either make antibodies more human or use smaller fragments, so that they are less likely to cause allergic reactions. The second method is to try and use a synthetic peptide. This will contain a series of amino acids which recognize a certain cell receptor. For example the somatostatin analogue Octreotide is an 8 amino acid peptide which has the same biological actions as natural somatostatin but an increased plasma half life. To this is added a linker a good example being DTPA and then radioisotope for example In-111. There we can have the complex In-111-DTPA-Octreotide which can be used to image somatostatin receptors in vivo. The main advantage over antibodies is that the cost production is less and many different variation of peptides for a particular receptor can be manufactured and assessed to find which is the optimal agent tumour imaging at a fraction of the cost of antibody production. There are two main approaches. Firstly to take a natural peptide hormone such as insulin or VIP and label by a simple method such as iodination with I-123. A group in Vienna have done it and shown good uptake of I-123 Insulin in primary hepatomas and of I-123 VIP in pancreatic cancers. Many natural peptide hormones however have a short plasma half

DISEÑO DE UN SISTEMA GONIOMÉTRICO CON TRES GRADOS DE LIBERTAD PARA MEDIR REFLECTANCIAS Y TEMPERATURAS RADIATIVAS EN EL SISTEMA SUELO-VEGETACIÓN

Directory of Open Access Journals (Sweden)

Alejandro Cano González

2014-01-01

Full Text Available La medición espectral multi-angular de la vegetación requiere de sistemas goniométricos costosos y pesados, difíciles de operar en condiciones de campo y laboratorio. Para facilitar este tipo de mediciones, se diseñó un sistema goniométrico (SIGO-CP simple de operar y de bajo costo, lo suficientemente flexible para ser usado en campo y laboratorio. El SIGO-CP, a diferencia de los sistemas actuales, tiene tres grados de libertad en vez de dos: acimutal, cenital y radial, permitiendo cambiar el área asociada al efecto de escala de las observaciones. El SIGO-CP fue ejemplificado en su implementación bajo condiciones de laboratorio, incluida la aplicación de eventos de precipitación con un simulador de lluvias, para experimentos de arreglos geométricos de especies vegetales en bolsas de plástico sobre las que se utiliza un fondo de suelo a la altura de los inicios de los tallos de las plantas.

Driving engineering of novel antimicrobial peptides from simulations of peptide-micelle interactions

DEFF Research Database (Denmark)

Khandelia, Himanshu; Langham, Allison A; Kaznessis, Yiannis N

2006-01-01

Simulations of antimicrobial peptides in membrane mimics can provide the high resolution, atomistic picture that is necessary to decipher which sequence and structure components are responsible for activity and toxicity. With such detailed insight, engineering new sequences that are active but non...... peptides and their interaction with membrane mimics. In this article, we discuss the promise and the challenges of widely used models and detail our recent work on peptide-micelle simulations as an attractive alternative to peptide-bilayer simulations. We detail our results with two large structural...... classes of peptides, helical and beta-sheet and demonstrate how simulations can assist in engineering of novel antimicrobials with therapeutic potential....

A novel tri-axis MEMS gyroscope with in-plane tetra-pendulum proof masses and enhanced sensitive springs

International Nuclear Information System (INIS)

Wang, M C; Jiao, J W; Yan, P L; Mi, B W; Qin, S

2014-01-01

This paper presents a tri-axis MEMS gyroscope design with novel tetra-pendulum proof masses for X-, Y-axis and regular proof masses for Z-axis rate sensing, which are all coupled with and embedded in a conventional tuning fork driving frame. The four pendulum proof masses are suspended via the torsional springs to a common center anchor and can be driven to swing around the anchor via the tilted transforming springs as the driving frame is oscillated in an anti-phase mode. As an X-, Y-axis angular rate is applied, the tetra-pendulum proof masses will rotate around the torsional springs in pairs for X- and Y-axis differential sensing, respectively. In particular, we investigated the relationship between the tilting angle of the transforming spring and its transforming efficiency, i.e. the amplitude ratio of the pendulum's swing to the driving oscillation, which shows a straight impact on the sensitivity. By theoretical analysis and Ansys simulation, we achieved an optimal tilting angle of 22.5°, which extends along the angular bisector of the pendulum's and driving mass’ moving direction and demonstrates a significant increase in transforming efficiency by about 40%, compared with the trivial tilting angle of 45°. By employing an SOI-based bulk micromachining process, the prototype device with the optimal design of the transforming spring (type I) and that with the trivial design (type II) for reference have been successfully fabricated. As expected, the testing results indicate an increase of more than 20% in the X- and Y- sensitivities, which is mainly from the enhanced sensitive transforming springs. (paper)

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

Science.gov (United States)

Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J; Telenti, Amalio; de Bakker, Paul I W; Walker, Bruce D; Ripke, Stephan; Brumme, Chanson J; Pulit, Sara L; Carrington, Mary; Kadie, Carl M; Carlson, Jonathan M; Heckerman, David; Graham, Robert R; Plenge, Robert M; Deeks, Steven G; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P; Guiducci, Candace; Gupta, Namrata; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L; Vine, Seanna; Addo, Marylyn M; Allen, Todd M; Altfeld, Marcus; Henn, Matthew R; Le Gall, Sylvie; Streeck, Hendrik; Haas, David W; Kuritzkes, Daniel R; Robbins, Gregory K; Shafer, Robert W; Gulick, Roy M; Shikuma, Cecilia M; Haubrich, Richard; Riddler, Sharon; Sax, Paul E; Daar, Eric S; Ribaudo, Heather J; Agan, Brian; Agarwal, Shanu; Ahern, Richard L; Allen, Brady L; Altidor, Sherly; Altschuler, Eric L; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C; Benson, Anne M; Berger, Judith; Bernard, Nicole F; Bernard, Annette M; Birch, Christopher; Bodner, Stanley J; Bolan, Robert K; Boudreaux, Emilie T; Bradley, Meg; Braun, James F; Brndjar, Jon E; Brown, Stephen J; Brown, Katherine; Brown, Sheldon T; Burack, Jedidiah; Bush, Larry M; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H; Carmichael, J Kevin; Casey, Kathleen K; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T; Chez, Nancy; Chirch, Lisa M; Cimoch, Paul J; Cohen, Daniel; Cohn, Lillian E; Conway, Brian; Cooper, David A; Cornelson, Brian; Cox, David T; Cristofano, Michael V; Cuchural, George; Czartoski, Julie L; Dahman, Joseph M; Daly, Jennifer S; Davis, Benjamin T; Davis, Kristine; Davod, Sheila M; DeJesus, Edwin; Dietz, Craig A; Dunham, Eleanor; Dunn, Michael E; Ellerin, Todd B; Eron, Joseph J; Fangman, John J W; Farel, Claire E; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A; French, Neel K; Fuchs, Jonathan D; Fuller, Jon D; Gaberman, Jonna; Gallant, Joel E; Gandhi, Rajesh T; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C; Gaultier, Cyril R; Gebre, Wondwoosen; Gilman, Frank D; Gilson, Ian; Goepfert, Paul A; Gottlieb, Michael S; Goulston, Claudia; Groger, Richard K; Gurley, T Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W David; Harrigan, P Richard; Hawkins, Trevor N; Heath, Sonya; Hecht, Frederick M; Henry, W Keith; Hladek, Melissa; Hoffman, Robert P; Horton, James M; Hsu, Ricky K; Huhn, Gregory D; Hunt, Peter; Hupert, Mark J; Illeman, Mark L; Jaeger, Hans; Jellinger, Robert M; John, Mina; Johnson, Jennifer A; Johnson, Kristin L; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C; Kauffman, Carol A; Khanlou, Homayoon; Killian, Robert K; Kim, Arthur Y; Kim, David D; Kinder, Clifford A; Kirchner, Jeffrey T; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P Todd; Kurisu, Wayne; Kwon, Douglas S; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M; Lee, David M; Lee, Jean M L; Lee, Marah J; Lee, Edward T Y; Lemoine, Janice; Levy, Jay A; Llibre, Josep M; Liguori, Michael A; Little, Susan J; Liu, Anne Y; Lopez, Alvaro J; Loutfy, Mono R; Loy, Dawn; Mohammed, Debbie Y; Man, Alan; Mansour, Michael K; Marconi, Vincent C; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N; Martin, Harold L; Mayer, Kenneth Hugh; McElrath, M Juliana; McGhee, Theresa A; McGovern, Barbara H; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X; Menezes, Prema; Mesa, Greg; Metroka, Craig E; Meyer-Olson, Dirk; Miller, Andy O; Montgomery, Kate; Mounzer, Karam C; Nagami, Ellen H; Nagin, Iris; Nahass, Ronald G; Nelson, Margret O; Nielsen, Craig; Norene, David L; O'Connor, David H; Ojikutu, Bisola O; Okulicz, Jason; Oladehin, Olakunle O; Oldfield, Edward C; Olender, Susan A; Ostrowski, Mario; Owen, William F; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M; Perlmutter, Aaron M; Pierce, Michael N; Pincus, Jonathan M; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J; Rhame, Frank S; Richards, Constance Shamuyarira; Richman, Douglas D; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C; Rosenberg, Eric S; Rosenthal, Daniel; Ross, Polly E; Rubin, David S; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R; Sanchez, William C; Sanjana, Veeraf M; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M; Shalit, Peter; Shay, William; Shirvani, Vivian N; Silebi, Vanessa I; Sizemore, James M; Skolnik, Paul R; Sokol-Anderson, Marcia; Sosman, James M; Stabile, Paul; Stapleton, Jack T; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F Lisa; Stone, Valerie E; Stone, David R; Tambussi, Giuseppe; Taplitz, Randy A; Tedaldi, Ellen M; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A; Trinh, Phuong D; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J; Vecino, Isabel; Vega, Vilma M; Veikley, Wenoah; Wade, Barbara H; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J; Warner, Daniel A; Weber, Robert D; Webster, Duncan; Weis, Steve; Wheeler, David A; White, David J; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G; van't Wout, Angelique; Wright, David P; Yang, Otto O; Yurdin, David L; Zabukovic, Brandon W; Zachary, Kimon C; Zeeman, Beth; Zhao, Meng

2010-12-10

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.

The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation

Science.gov (United States)

Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I.W.; Walker, Bruce D.; Jia, Xiaoming; McLaren, Paul J.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Telenti, Amalio; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.; Heckerman, David; de Bakker, Paul I.W.; Pereyra, Florencia; de Bakker, Paul I.W.; Graham, Robert R.; Plenge, Robert M.; Deeks, Steven G.; Walker, Bruce D.; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M.; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P.; Guiducci, Candace; Gupta, Namrata; Carrington, Mary; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Pereyra, Florencia; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L.; Lemay, Paul; O’Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L.; Vine, Seanna; Addo, Marylyn M.; Allen, Todd M.; Altfeld, Marcus; Henn, Matthew R.; Le Gall, Sylvie; Streeck, Hendrik; Walker, Bruce D.; Haas, David W.; Kuritzkes, Daniel R.; Robbins, Gregory K.; Shafer, Robert W.; Gulick, Roy M.; Shikuma, Cecilia M.; Haubrich, Richard; Riddler, Sharon; Sax, Paul E.; Daar, Eric S.; Ribaudo, Heather J.; Agan, Brian; Agarwal, Shanu; Ahern, Richard L.; Allen, Brady L.; Altidor, Sherly; Altschuler, Eric L.; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J.; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C.; Benson, Anne M.; Berger, Judith; Bernard, Nicole F.; Bernard, Annette M.; Birch, Christopher; Bodner, Stanley J.; Bolan, Robert K.; Boudreaux, Emilie T.; Bradley, Meg; Braun, James F.; Brndjar, Jon E.; Brown, Stephen J.; Brown, Katherine; Brown, Sheldon T.; Burack, Jedidiah; Bush, Larry M.; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H.; Carmichael, J. Kevin; Casey, Kathleen K.; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T.; Chez, Nancy; Chirch, Lisa M.; Cimoch, Paul J.; Cohen, Daniel; Cohn, Lillian E.; Conway, Brian; Cooper, David A.; Cornelson, Brian; Cox, David T.; Cristofano, Michael V.; Cuchural, George; Czartoski, Julie L.; Dahman, Joseph M.; Daly, Jennifer S.; Davis, Benjamin T.; Davis, Kristine; Davod, Sheila M.; Deeks, Steven G.; DeJesus, Edwin; Dietz, Craig A.; Dunham, Eleanor; Dunn, Michael E.; Ellerin, Todd B.; Eron, Joseph J.; Fangman, John J.W.; Farel, Claire E.; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A.; French, Neel K.; Fuchs, Jonathan D.; Fuller, Jon D.; Gaberman, Jonna; Gallant, Joel E.; Gandhi, Rajesh T.; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C.; Gaultier, Cyril R.; Gebre, Wondwoosen; Gilman, Frank D.; Gilson, Ian; Goepfert, Paul A.; Gottlieb, Michael S.; Goulston, Claudia; Groger, Richard K.; Gurley, T. Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W. David; Harrigan, P. Richard; Hawkins, Trevor N.; Heath, Sonya; Hecht, Frederick M.; Henry, W. Keith; Hladek, Melissa; Hoffman, Robert P.; Horton, James M.; Hsu, Ricky K.; Huhn, Gregory D.; Hunt, Peter; Hupert, Mark J.; Illeman, Mark L.; Jaeger, Hans; Jellinger, Robert M.; John, Mina; Johnson, Jennifer A.; Johnson, Kristin L.; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C.; Kauffman, Carol A.; Khanlou, Homayoon; Killian, Robert K.; Kim, Arthur Y.; Kim, David D.; Kinder, Clifford A.; Kirchner, Jeffrey T.; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P. Todd; Kurisu, Wayne; Kwon, Douglas S.; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M.; Lee, David M.; Lee, Jean M.L.; Lee, Marah J.; Lee, Edward T.Y.; Lemoine, Janice; Levy, Jay A.; Llibre, Josep M.; Liguori, Michael A.; Little, Susan J.; Liu, Anne Y.; Lopez, Alvaro J.; Loutfy, Mono R.; Loy, Dawn; Mohammed, Debbie Y.; Man, Alan; Mansour, Michael K.; Marconi, Vincent C.; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N.; Martin, Harold L.; Mayer, Kenneth Hugh; McElrath, M. Juliana; McGhee, Theresa A.; McGovern, Barbara H.; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X.; Menezes, Prema; Mesa, Greg; Metroka, Craig E.; Meyer-Olson, Dirk; Miller, Andy O.; Montgomery, Kate; Mounzer, Karam C.; Nagami, Ellen H.; Nagin, Iris; Nahass, Ronald G.; Nelson, Margret O.; Nielsen, Craig; Norene, David L.; O’Connor, David H.; Ojikutu, Bisola O.; Okulicz, Jason; Oladehin, Olakunle O.; Oldfield, Edward C.; Olender, Susan A.; Ostrowski, Mario; Owen, William F.; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M.; Perlmutter, Aaron M.; Pierce, Michael N.; Pincus, Jonathan M.; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C.; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J.; Rhame, Frank S.; Richards, Constance Shamuyarira; Richman, Douglas D.; Robbins, Gregory K.; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C.; Rosenberg, Eric S.; Rosenthal, Daniel; Ross, Polly E.; Rubin, David S.; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R.; Sanchez, William C.; Sanjana, Veeraf M.; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M.; Shalit, Peter; Shay, William; Shirvani, Vivian N.; Silebi, Vanessa I.; Sizemore, James M.; Skolnik, Paul R.; Sokol-Anderson, Marcia; Sosman, James M.; Stabile, Paul; Stapleton, Jack T.; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F. Lisa; Stone, Valerie E.; Stone, David R.; Tambussi, Giuseppe; Taplitz, Randy A.; Tedaldi, Ellen M.; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A.; Trinh, Phuong D.; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J.; Vecino, Isabel; Vega, Vilma M.; Veikley, Wenoah; Wade, Barbara H.; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J.; Warner, Daniel A.; Weber, Robert D.; Webster, Duncan; Weis, Steve; Wheeler, David A.; White, David J.; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G.; Wout, Angelique van’t; Wright, David P.; Yang, Otto O.; Yurdin, David L.; Zabukovic, Brandon W.; Zachary, Kimon C.; Zeeman, Beth; Zhao, Meng

2011-01-01

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA–viral peptide interaction as the major factor modulating durable control of HIV infection. PMID:21051598

Estrategia para el diseño paramétrico basado en modelos.

Directory of Open Access Journals (Sweden)

S. A. Marrero Osorio

2008-09-01

Full Text Available El presente artículo expone una manera de diseñar paramétricamente utilizando los programas de computadora (CAD, CAE, PMS difundidos entre los diseñadores durante los últimos 20 años. La propuesta se basa en modelos matemáticos que consideran el conocimiento sobre la ingeniería del objeto de diseño y lo relacionado con la confección de su modelo virtual tridimensional, planos y otro aspectos; utilizando el Método de los Grafos Dicromáticos para resolver los problemas computacionales que se presentan en el diseño paramétrico. Se analizan los puntos de vista de diferentes autores en relación con el proceso general de diseño y es ubicado dentro del mismo el diseño paramétrico, realizándose una explicación formal que permite arribar a conclusiones interesantes.The present article exposes a way to design parametrically applying programs (CAD, CAE, PMS accepted by designers along the last 20 years. The proposal is based on mathematical models that ponder the knowledge on the engineering of the design object and the building of its three-dimensional virtual models, blueprints and another aspects; using the dichromatic graph method to solve computational problems in parametric design. The points of view of different authors are analyzed in connection with the general process of design, locating parametric design inside it, carrying out a formal explanation which arrives to interesting conclusions.

Levantamiento topográfico y fotogramétrico del anfiteatro romano de Tarragona

OpenAIRE

Oliver Gañán, Raúl

2013-01-01

El proyecto consiste en el levantamiento topográfico y fotogramétrico terrestre a escala 1/400 del Anfiteatro Romano de Tarragona, georeferenciado a partir de vértices de coordenadas conocidas proporcionadas por el Institut Català d’Arqueologia Clàssica de Tarragona. Se obtiene como resultado final un modelo en tres dimensiones del anfiteatro, así como planos en planta y alzado. Se adjunta un dosier con Anejos en los que se incluye información relevante, planos y las ortoimá...

Flanking signal and mature peptide residues influence signal peptide cleavage

Directory of Open Access Journals (Sweden)

Ranganathan Shoba

2008-12-01

Full Text Available Abstract Background Signal peptides (SPs mediate the targeting of secretory precursor proteins to the correct subcellular compartments in prokaryotes and eukaryotes. Identifying these transient peptides is crucial to the medical, food and beverage and biotechnology industries yet our understanding of these peptides remains limited. This paper examines the most common type of signal peptides cleavable by the endoprotease signal peptidase I (SPase I, and the residues flanking the cleavage sites of three groups of signal peptide sequences, namely (i eukaryotes (Euk (ii Gram-positive (Gram+ bacteria, and (iii Gram-negative (Gram- bacteria. Results In this study, 2352 secretory peptide sequences from a variety of organisms with amino-terminal SPs are extracted from the manually curated SPdb database for analysis based on physicochemical properties such as pI, aliphatic index, GRAVY score, hydrophobicity, net charge and position-specific residue preferences. Our findings show that the three groups share several similarities in general, but they display distinctive features upon examination in terms of their amino acid compositions and frequencies, and various physico-chemical properties. Thus, analysis or prediction of their sequences should be separated and treated as distinct groups. Conclusion We conclude that the peptide segment recognized by SPase I extends to the start of the mature protein to a limited extent, upon our survey of the amino acid residues surrounding the cleavage processing site. These flanking residues possibly influence the cleavage processing and contribute to non-canonical cleavage sites. Our findings are applicable in defining more accurate prediction tools for recognition and identification of cleavage site of SPs.

Analysis of peptide uptake and location of root hair-promoting peptide accumulation in plant roots.

Science.gov (United States)

Matsumiya, Yoshiki; Taniguchi, Rikiya; Kubo, Motoki

2012-03-01

Peptide uptake by plant roots from degraded soybean-meal products was analyzed in Brassica rapa and Solanum lycopersicum. B. rapa absorbed about 40% of the initial water volume, whereas peptide concentration was decreased by 75% after 24 h. Analysis by reversed-phase HPLC showed that number of peptides was absorbed by the roots during soaking in degraded soybean-meal products for 24 h. Carboxyfluorescein-labeled root hair-promoting peptide was synthesized, and its localization, movement, and accumulation in roots were investigated. The peptide appeared to be absorbed by root hairs and then moved to trichoblasts. Furthermore, the peptide was moved from trichoblasts to atrichoblasts after 24 h. The peptide was accumulated in epidermal cells, suggesting that the peptide may have a function in both trichoblasts and atrichoblasts. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.

Nonlinear optical properties of systems based on ruthenium(II) tetra-15-crown-5-phthalocyaninate

International Nuclear Information System (INIS)

Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Vannikov, A.V.; Tsivadze, A.Yu.

2008-01-01

The third-order nonlinear optical properties of the ruthenium (II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules (R 4 Pc)Ru(TED) 2 were analyzed by means of the z-scanning technique. A solution of (R 4 Pc)Ru(TED) 2 in tetrachloroethane was exposed to nanosecond laser pulses at a wavelength of 1064 nm. It was found that the third-order molecular polarizability of the Ru(II) complex is 4.5 x 10 -32 cm 4 /C (esu). The polarizability per molecule increases by a factor of 3.6 when the single molecule occurs in a supramolecular assembly of (R 4 Pc)Ru(TED) 2 complexes. The photoelectric and photorefractive properties at 1064 nm of polymer composites, determined by the supramolecular assemblies that exhibits optical absorption and photoelectric sensitivity in the near IR region, are reported [ru

A general strategy to endow natural fusion-protein-derived peptides with potent antiviral activity.

Directory of Open Access Journals (Sweden)

Antonello Pessi

Full Text Available Fusion between the viral and target cell membranes is an obligatory step for the infectivity of all enveloped virus, and blocking this process is a clinically validated therapeutic strategy.Viral fusion is driven by specialized proteins which, although specific to each virus, act through a common mechanism, the formation of a complex between two heptad repeat (HR regions. The HR regions are initially separated in an intermediate termed "prehairpin", which bridges the viral and cell membranes, and then fold onto each other to form a 6-helical bundle (6HB, driving the two membranes to fuse. HR-derived peptides can inhibit viral infectivity by binding to the prehairpin intermediate and preventing its transition to the 6HB.The antiviral activity of HR-derived peptides differs considerably among enveloped viruses. For weak inhibitors, potency can be increased by peptide engineering strategies, but sequence-specific optimization is time-consuming. In seeking ways to increase potency without changing the native sequence, we previously reported that attachment to the HR peptide of a cholesterol group ("cholesterol-tagging" dramatically increases its antiviral potency, and simultaneously increases its half-life in vivo. We show here that antiviral potency may be increased by combining cholesterol-tagging with dimerization of the HR-derived sequence, using as examples human parainfluenza virus, Nipah virus, and HIV-1. Together, cholesterol-tagging and dimerization may represent strategies to boost HR peptide potency to levels that in some cases may be compatible with in vivo use, possibly contributing to emergency responses to outbreaks of existing or novel viruses.

Complete covalent structure of statherin, a tyrosine-rich acidic peptide which inhibits calcium phosphate precipitation from human parotid saliva.

Science.gov (United States)

Schlesinger, D H; Hay, D I

1977-03-10

The complete amino acid sequence of human salivary statherin, a peptide which strongly inhibits precipitation from supersaturated calcium phosphate solutions, and therefore stabilizes supersaturated saliva, has been determined. The NH2-terminal half of this Mr=5380 (43 amino acids) polypeptide was determined by automated Edman degradations (liquid phase) on native statherin. The peptide was digested separately with trypsin, chymotrypsin, and Staphylococcus aureus protease, and the resulting peptides were purified by gel filtration. Manual Edman degradations on purified peptide fragments yielded peptides that completed the amino acid sequence through the penultimate COOH-terminal residue. These analyses, together with carboxypeptidase digestion of native statherin and of peptide fragments of statherin, established the complete sequence of the molecule. The 2 serine residues (positions 2 and 3) in statherin were identified as phosphoserine. The amino acid sequence of human salivary statherin is striking in a number of ways. The NH2-terminal one-third is highly polar and includes three polar dipeptides: H2PO3-Ser-Ser-H2PO3-Arg-Arg-, and Glu-Glu-. The COOH-terminal two-thirds of the molecule is hydrophobic, containing several repeating dipeptides: four of -Gn-Pro-, three of -Tyr-Gln-, two of -Gly-Tyr-, two of-Gln-Tyr-, and two of the tetrapeptide sequence -Pro-Tyr-Gln-Pro-. Unusual cleavage sites in the statherin sequence obtained with chymotrypsin and S. aureus protease were also noted.

Características clínicas y sociolaborales de pacientes psiquiátricos al término de la incapacidad temporal por contingencia común

Directory of Open Access Journals (Sweden)

J.I. Pastrana-Jiménez

2013-06-01

Full Text Available Introducción: La patología psiquiátrica es la principal causa de pérdida de calidad de vida y presenta unos altísimos costes, personales y económicos. Pese a ello, existen pocos datos sobre las características de los pacientes psiquiátricos con incapacidad laboral y sus características clínicas. Por ello nos proponemos describir estas características en los pacientes con más de 12 meses de incapacidad temporal e investigar factores que puedan estar ligados a cronicidad o disfunción. Material y métodos: Sobre el total de pacientes derivados por el INSS para evaluación psiquiátrica, se excluyeron aquellos que no se encontraran en Incapacidad Temporal o que llevaran menos de 12 meses, conformando una muestra de 97 pacientes. Se registraron las principales características sociolaborales y clínicas, diagnóstico según criterios DSM-IV-TR, se aplicaron escalas de funcionalidad e intensidad sintomatológica como EEAG, MADRS y WHODAS O. Resultados: La distribución por sexos fue homogénea, con una edad media de 47 años, vive en pareja el 51,5%, normalmente refieren una vivencia de apoyo social moderado y 1/3 no ha superado estudios primarios. El 78,4% presenta antecedentes físicos importantes, fuma 50,5%, 59% tiene antecedentes familiares psiquiátricos, que tienden a asociarse a baja funcionalidad y tratamientos más prolongados. La concordancia diagnóstica es del 71,1%, los trastornos afectivos son el grupo diagnóstico más frecuente. El trastorno adaptativo es el diagnóstico más frecuente en el grupo al que no se le encuentra limitación funcional y se asocia a menos tiempo en tratamiento y a menos intensidad sintomatológica. Las escalas utilizadas correlacionan entre sí, distinguiendo EEAG y WHODAS O a los trastornos adaptativos y a los cuadros no incapacitados, mientras que MADRS señala a los trastornos afectivos. Tras la evaluación, al 46,39% no se le propone incapacidad, al 11,34% se le solicita prórroga, al 29

Consequences of non-uniformity in the stoichiometry of component fractions within one and two loops models of alpha-helical peptides

Science.gov (United States)

Atoms in biomolecular structures like alpha helices contain an array of distances and angles which include abundant multiple patterns of redundancies. Thus all peptides backbones contain the three atom sequence N-C*C, whereas the repeating set of a four atom sequences (N-C*C-N, C*-C-N-C*, and C-N-C...

Insulin C-peptide test

Science.gov (United States)

C-peptide ... the test depends on the reason for the C-peptide measurement. Ask your health care provider if ... C-peptide is measured to tell the difference between insulin the body produces and insulin someone injects ...

Double-Stranded Peptide Nucleic Acids

DEFF Research Database (Denmark)

2001-01-01

A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.......A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

Application of synthetic peptides for detection of anti-citrullinated peptide antibodies

DEFF Research Database (Denmark)

Trier, Nicole Hartwig; Holm, Bettina Eide; Slot, Ole

2016-01-01

Anti-citrullinated protein antibodies (ACPAs) are a hallmark of rheumatoid arthritis (RA) and represent an important tool for the serological diagnosis of RA. In this study, we describe ACPA reactivity to overlapping citrullinated Epstein-Barr virus nuclear antigen-1 (EBNA-1)-derived peptides...... (n=40), systemic lupus erythematosus (n=20), Sjögren's syndrome (n=40)) were screened for antibody reactivity. Antibodies to a panel of five citrullinated EBNA-1 peptides were found in 67% of RA sera, exclusively of the IgG isotype, while 53% of the patient sera reacted with a single peptide......, ARGGSRERARGRGRG-Cit-GEKR, accounting for more than half of the ACPA reactivity alone. Moreover, these antibodies were detected in 10% of CCP2-negative RA sera. In addition, 47% of the RA sera reacted with two or three citrullinated EBNA-1 peptides from the selected peptide panel. Furthermore, a negative...

Análisis fotométrico-espectroscópico de un par de binarias en NGC 3532

Science.gov (United States)

Gramajo, L.; González, J. F.

Presentamos el informe de avance de un proyecto que apunta a la determinación de masas y radios de precisión en estrellas tempranas de cúmulos abiertos mediante el análisis fotométrico-espectroscópico de sistemas binarios detached con baja rotación. Con ello se pretende determinar el estado evolutivo de estas estrellas y confrontar su estructura con modelos estelares teóricos con distinto grado de ``overshooting". Los primeros objetos seleccionados son dos sistemas binarios de espectros dobles (BDA27 y BDA363) detectados en el cúmulo NGC 3532. Presentamos la órbita espectroscópica obtenida para la binaria eclipsante BDA27, para la cual obtuvimos un período de 4.29 días y una razón de masas q=0.62. Derivamos sus parámetros absolutos preliminares usando nuestra curva de velocidad y datos fotométricos existentes en la literatura, y presentamos estimas del alcance de nuestros resultados una vez que hayamos completado nuestras observaciones con nuevas curvas de luz.

Representing environment-induced helix-coil transitions in a coarse grained peptide model

Science.gov (United States)

Dalgicdir, Cahit; Globisch, Christoph; Sayar, Mehmet; Peter, Christine

2016-10-01

Coarse grained (CG) models are widely used in studying peptide self-assembly and nanostructure formation. One of the recurrent challenges in CG modeling is the problem of limited transferability, for example to different thermodynamic state points and system compositions. Understanding transferability is generally a prerequisite to knowing for which problems a model can be reliably used and predictive. For peptides, one crucial transferability question is whether a model reproduces the molecule's conformational response to a change in its molecular environment. This is of particular importance since CG peptide models often have to resort to auxiliary interactions that aid secondary structure formation. Such interactions take care of properties of the real system that are per se lost in the coarse graining process such as dihedral-angle correlations along the backbone or backbone hydrogen bonding. These auxiliary interactions may then easily overstabilize certain conformational propensities and therefore destroy the ability of the model to respond to stimuli and environment changes, i.e. they impede transferability. In the present paper we have investigated a short peptide with amphiphilic EALA repeats which undergoes conformational transitions between a disordered and a helical state upon a change in pH value or due to the presence of a soft apolar/polar interface. We designed a base CG peptide model that does not carry a specific (backbone) bias towards a secondary structure. This base model was combined with two typical approaches of ensuring secondary structure formation, namely a C α -C α -C α -C α pseudodihedral angle potential or a virtual site interaction that mimics hydrogen bonding. We have investigated the ability of the two resulting CG models to represent the environment-induced conformational changes in the helix-coil equilibrium of EALA. We show that with both approaches a CG peptide model can be obtained that is environment-transferable and that

Primary structure and conformational analysis of peptide methionine-tyrosine, a peptide related to neuropeptide Y and peptide YY isolated from lamprey intestine

DEFF Research Database (Denmark)

Conlon, J M; Bjørnholm, B; Jørgensen, Flemming Steen

1991-01-01

A peptide belonging to the pancreatic-polypeptide-fold family of regulatory peptides has been isolated from the intestine of an Agnathan, the sea lamprey (Petromyzon marinus). The primary structure of the peptide (termed peptide methionine-tyrosine) was established as Met-Pro-Pro-Lys-Pro-Asp-Asn-...... in a preferred structure in which the conformation of the beta-turn between the two helical domains (residues 9-14) is appreciably different....

Improving Peptide Applications Using Nanotechnology.

Science.gov (United States)

Narayanaswamy, Radhika; Wang, Tao; Torchilin, Vladimir P

2016-01-01

Peptides are being successfully used in various fields including therapy and drug delivery. With advancement in nanotechnology and targeted delivery carrier systems, suitable modification of peptides has enabled achievement of many desirable goals over-riding some of the major disadvantages associated with the delivery of peptides in vivo. Conjugation or physical encapsulation of peptides to various nanocarriers, such as liposomes, micelles and solid-lipid nanoparticles, has improved their in vivo performance multi-fold. The amenability of peptides to modification in chemistry and functionalization with suitable nanocarriers are very relevant aspects in their use and have led to the use of 'smart' nanoparticles with suitable linker chemistries that favor peptide targeting or release at the desired sites, minimizing off-target effects. This review focuses on how nanotechnology has been used to improve the number of peptide applications. The paper also focuses on the chemistry behind peptide conjugation to nanocarriers, the commonly employed linker chemistries and the several improvements that have already been achieved in the areas of peptide use with the help of nanotechnology.

Peptide and Peptide-Dependent Motions in MHC Proteins: Immunological Implications and Biophysical Underpinnings

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Cory M. Ayres

2017-08-01

Full Text Available Structural biology of peptides presented by class I and class II MHC proteins has transformed immunology, impacting our understanding of fundamental immune mechanisms and allowing researchers to rationalize immunogenicity and design novel vaccines. However, proteins are not static structures as often inferred from crystallographic structures. Their components move and breathe individually and collectively over a range of timescales. Peptides bound within MHC peptide-binding grooves are no exception and their motions have been shown to impact recognition by T cell and other receptors in ways that influence function. Furthermore, peptides tune the motions of MHC proteins themselves, which impacts recognition of peptide/MHC complexes by other proteins. Here, we review the motional properties of peptides in MHC binding grooves and discuss how peptide properties can influence MHC motions. We briefly review theoretical concepts about protein motion and highlight key data that illustrate immunological consequences. We focus primarily on class I systems due to greater availability of data, but segue into class II systems as the concepts and consequences overlap. We suggest that characterization of the dynamic “energy landscapes” of peptide/MHC complexes and the resulting functional consequences is one of the next frontiers in structural immunology.

Sticky water surfaces: Helix-​coil transitions suppressed in a cell-​penetrating peptide at the air-​water interface

NARCIS (Netherlands)

Schach, D.; Globisch, C.; Roeters, S.J.; Woutersen, S.; Fuchs, A.; Weiss, C.K.; Backus, E.H.G.; Landfester, K.; Bonn, M.; Peter, C.; Weidner, T.

2014-01-01

GALA is a 30 amino acid synthetic peptide consisting of a Glu-​Ala-​Leu-​Ala repeat and is known to undergo a reversible structural transition from a disordered to an α-​helical structure when changing the pH from basic to acidic values. In its helical state GALA can insert into and disintegrate

Biosynthesis of cardiac natriuretic peptides

DEFF Research Database (Denmark)

Goetze, Jens Peter

2010-01-01

Cardiac-derived peptide hormones were identified more than 25 years ago. An astonishing amount of clinical studies have established cardiac natriuretic peptides and their molecular precursors as useful markers of heart disease. In contrast to the clinical applications, the biogenesis of cardiac...... peptides has only been elucidated during the last decade. The cellular synthesis including amino acid modifications and proteolytic cleavages has proven considerably more complex than initially perceived. Consequently, the elimination phase of the peptide products in circulation is not yet well....... An inefficient post-translational prohormone maturation will also affect the biology of the cardiac natriuretic peptide system. This review aims at summarizing the myocardial synthesis of natriuretic peptides focusing on B-type natriuretic peptide, where new data has disclosed cardiac myocytes as highly...

Acetone-Linked Peptides: A Convergent Approach for Peptide Macrocyclization and Labeling.

Science.gov (United States)

Assem, Naila; Ferreira, David J; Wolan, Dennis W; Dawson, Philip E

2015-07-20

Macrocyclization is a broadly applied approach for overcoming the intrinsically disordered nature of linear peptides. Herein, it is shown that dichloroacetone (DCA) enhances helical secondary structures when introduced between peptide nucleophiles, such as thiols, to yield an acetone-linked bridge (ACE). Aside from stabilizing helical structures, the ketone moiety embedded in the linker can be modified with diverse molecular tags by oxime ligation. Insights into the structure of the tether were obtained through co-crystallization of a constrained S-peptide in complex with RNAse S. The scope of the acetone-linked peptides was further explored through the generation of N-terminus to side chain macrocycles and a new approach for generating fused macrocycles (bicycles). Together, these studies suggest that acetone linking is generally applicable to peptide macrocycles with a specific utility in the synthesis of stabilized helices that incorporate functional tags. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Review on Recent Patents and Applications of Inorganic Material Binding Peptides.

Science.gov (United States)

Thota, Veeranjaneyulu; Perry, Carole C

2017-01-01

Although the popularity of using combinatorial display techniques for recognising unique peptides having high affinity for inorganic (nano) particles has grown rapidly, there are no systematic reviews showcasing current developments or patents on binding peptides specific to these materials. In this review, we summarize and discuss recent progress in patents on material binding peptides specifically exploring inorganic nano surfaces such as metals, metal oxides, minerals, carbonbased materials, polymer based materials, magnetic materials and semiconductors. We consider both the peptide display strategies used and the exploitation of the identified peptides in the generation of advanced nanomaterials. In order to get a clear picture on the number of patents and literature present to date relevant to inorganic material binding biomolecules and their applications, a thorough online search was conducted using national and worldwide databases. The literature search include standard bibliographic databases while patents included EPO Espacenet, WIPO patent scope, USPTO, Google patent search, Patent lens, etc. along with commercial databases such as Derwent and Patbase. Both English and American spellings were included in the searches. The initial number of patents found related to material binders were 981. After reading and excluding irrelevant patents such as organic binding peptides, works published before 2001, repeated patents, documents not in English etc., 51 highly relevant patents published from 2001 onwards were selected and analysed. These patents were further separated into six categories based on their target inorganic material and combinatorial library used. They include relevant patents on metal, metal oxide or combination binding peptides (19), magnetic and semiconductor binding peptides (8), carbon based (3), mineral (5), polymer (8) and other binders (9). Further, how these material specific binders have been used to synthesize simple to complex bio- or

Preparation of peptide thioesters through fmoc-based solid-phase peptide synthesis by using amino thioesters

DEFF Research Database (Denmark)

Stuhr-Hansen, N.; Wilbek, T.S.; Strømgaard, K.

2013-01-01

protected peptide thioester, which was globally deprotected to afford the desired unprotected peptide thioester. The method is compatible with labile groups such as phosphoryl and glycosyl moieties. The synthesis of peptide alkyl thioesters by 9-fluorenylmethoxycarbonyl (Fmoc) solid-phase peptide synthesis...

Production and characterization of peptide antibodies

DEFF Research Database (Denmark)

Trier, Nicole Hartwig; Hansen, Paul Robert; Houen, Gunnar

2012-01-01

Proteins are effective immunogens for generation of antibodies. However, occasionally the native protein is known but not available for antibody production. In such cases synthetic peptides derived from the native protein are good alternatives for antibody production. These peptide antibodies...... are powerful tools in experimental biology and are easily produced to any peptide of choice. A widely used approach for production of peptide antibodies is to immunize animals with a synthetic peptide coupled to a carrier protein. Very important is the selection of the synthetic peptide, where factors......, including solid-phase peptide-carrier conjugation and peptide-carrier conjugation in solution. Upon immunization, adjuvants such as Al(OH)(3) are added together with the immunogenic peptide-carrier conjugate, which usually leads to high-titred antisera. Following immunization and peptide antibody...

Peptide ligands for targeting the extracellular domain of EGFR: Comparison between linear and cyclic peptides.

Science.gov (United States)

Williams, Tyrslai M; Sable, Rushikesh; Singh, Sitanshu; Vicente, Maria Graca H; Jois, Seetharama D

2018-02-01

Colorectal cancer (CRC) is the third most common solid internal malignancy among cancers. Early detection of cancer is key to increasing the survival rate of colorectal cancer patients. Overexpression of the EGFR protein is associated with CRC. We have designed a series of peptides that are highly specific for the extracellular domain of EGFR, based on our earlier studies on linear peptides. The previously reported linear peptide LARLLT, known to bind to EGFR, was modified with the goals of increasing its stability and its specificity toward EGFR. Peptide modifications, including D-amino acid substitution, cyclization, and chain reversal, were investigated. In addition, to facilitate labeling of the peptide with a fluorescent dye, an additional lysine residue was introduced onto the linear (KLARLLT) and cyclic peptides cyclo(KLARLLT) (Cyclo.L1). The lysine residue was also converted into an azide group in both a linear and reversed cyclic peptide sequences cyclo(K(N3)larllt) (Cyclo.L1.1) to allow for subsequent "click" conjugation. The cyclic peptides showed enhanced binding to EGFR by SPR. NMR and molecular modeling studies suggest that the peptides acquire a β-turn structure in solution. In vitro stability studies in human serum show that the cyclic peptide is more stable than the linear peptide. © 2017 John Wiley & Sons A/S.

Peptide Nucleic Acids (PNA)

DEFF Research Database (Denmark)

2002-01-01

A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

Peptide Nucleic Acid Synthons

DEFF Research Database (Denmark)

2004-01-01

A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

Usefulness of repeated N-terminal pro-B-type natriuretic peptide measurements as incremental predictor for long-term cardiovascular outcome after vascular surgery.

Science.gov (United States)

Goei, Dustin; van Kuijk, Jan-Peter; Flu, Willem-Jan; Hoeks, Sanne E; Chonchol, Michel; Verhagen, Hence J M; Bax, Jeroen J; Poldermans, Don

2011-02-15

Plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels improve preoperative cardiac risk stratification in vascular surgery patients. However, single preoperative measurements of NT-pro-BNP cannot take into account the hemodynamic stress caused by anesthesia and surgery. Therefore, the aim of the present study was to assess the incremental predictive value of changes in NT-pro-BNP during the perioperative period for long-term cardiac mortality. Detailed cardiac histories, rest left ventricular echocardiography, and NT-pro-BNP levels were obtained in 144 patients before vascular surgery and before discharge. The study end point was the occurrence of cardiovascular death during a median follow-up period of 13 months (interquartile range 5 to 20). Preoperatively, the median NT-pro-BNP level in the study population was 314 pg/ml (interquartile range 136 to 1,351), which increased to a median level of 1,505 pg/ml (interquartile range 404 to 6,453) before discharge. During the follow-up period, 29 patients (20%) died, 27 (93%) from cardiovascular causes. The median difference in NT-pro-BNP in the survivors was 665 pg/ml, compared to 5,336 pg/ml in the patients who died (p = 0.01). Multivariate Cox regression analyses, adjusted for cardiac history and cardiovascular risk factors (age, angina pectoris, myocardial infarction, stroke, diabetes mellitus, renal dysfunction, body mass index, type of surgery and the left ventricular ejection fraction), demonstrated that the difference in NT-pro-BNP level between pre- and postoperative measurement was the strongest independent predictor of cardiac outcome (hazard ratio 3.06, 95% confidence interval 1.36 to 6.91). In conclusion, the change in NT-pro-BNP, indicated by repeated measurements before surgery and before discharge is the strongest predictor of cardiac outcomes in patients who undergo vascular surgery. Copyright © 2011 Elsevier Inc. All rights reserved.

Vaccination with p53-peptide-pulsed dendritic cells, of patients with advanced breast cancer: report from a phase I study

DEFF Research Database (Denmark)

Svane, Inge Marie; Pedersen, Anders E; Johnsen, Hans E

2004-01-01

the treatment. In conclusion, the strategy for p53-DC vaccination seems safe and without toxicity. Furthermore, indications of both immunologic and clinical effect were found in heavily pretreated patients with advanced breast cancer. An independent clinical effect of repeated administration of DCs and IL-2 can......Peptides derived from over-expressed p53 protein are presented by class I MHC molecules and may act as tumour-associated epitopes. Due to the diversity of p53 mutations, immunogenic peptides representing wild-type sequences are preferable as a basis for a broad-spectrum p53-targeting cancer vaccine......) loaded with a cocktail of three wild-type and three modified p53 peptides are being analysed in six HLA-A2+ patients with progressive advanced breast cancer. Vaccinations were well tolerated and no toxicity was observed. Disease stabilisation was seen in two of six patients, one patient had a transient...

Aspectos psiquiátricos da obesidade

Directory of Open Access Journals (Sweden)

Dobrow Ilyse J

2002-01-01

Full Text Available Pesquisas recentes mostram que a obesidade é, em grande parte, o produto da vulnerabilidade genética mediada por um ambiente promotor da doença, o que sugere que os modelos biológicos podem ser mais úteis que os psicológicos para entender seu início e manutenção. No entanto, entre os pacientes que procuram tratamento, a obesidade tem sido associada a outros transtornos psiquiátricos, especialmente à depressão, o que sugere que a comorbidade psiquiátrica deve ser considerada na avaliação e no manejo clínicos. Além disso, embora a obesidade não seja em si mesma um transtorno alimentar, um subgrupo de indivíduos obesos, incluídos aqueles com o transtorno de compulsão alimentar periódica (TCAP e com a síndrome do comer noturno - SCN (night eating syndrome - NES sofrem de transtornos alimentares. Os psiquiatras podem e devem ter um papel ativo no tratamento da comorbidade ou de patologias relacionadas à alimentação e no auxílio aos pacientes obesos para que façam escolhas de estilos de vida saudáveis que levem a um maior bem-estar em termos físicos e psicológicos.

Three-Dimensional Graphene–RGD Peptide Nanoisland Composites That Enhance the Osteogenesis of Human Adipose-Derived Mesenchymal Stem Cells

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Ee-Seul Kang

2018-02-01

Full Text Available Graphene derivatives have immense potential in stem cell research. Here, we report a three-dimensional graphene/arginine-glycine-aspartic acid (RGD peptide nanoisland composite effective in guiding the osteogenesis of human adipose-derived mesenchymal stem cells (ADSCs. Amine-modified silica nanoparticles (SiNPs were uniformly coated onto an indium tin oxide electrode (ITO, followed by graphene oxide (GO encapsulation and electrochemical deposition of gold nanoparticles. A RGD–MAP–C peptide, with a triple-branched repeating RGD sequence and a terminal cysteine, was self-assembled onto the gold nanoparticles, generating the final three-dimensional graphene–RGD peptide nanoisland composite. We generated substrates with various gold nanoparticle–RGD peptide cluster densities, and found that the platform with the maximal number of clusters was most suitable for ADSC adhesion and spreading. Remarkably, the same platform was also highly efficient at guiding ADSC osteogenesis compared with other substrates, based on gene expression (alkaline phosphatase (ALP, runt-related transcription factor 2, enzyme activity (ALP, and calcium deposition. ADSCs induced to differentiate into osteoblasts showed higher calcium accumulations after 14–21 days than when grown on typical GO-SiNP complexes, suggesting that the platform can accelerate ADSC osteoblastic differentiation. The results demonstrate that a three-dimensional graphene–RGD peptide nanoisland composite can efficiently derive osteoblasts from mesenchymal stem cells.

Solid-phase peptide synthesis

DEFF Research Database (Denmark)

Jensen, Knud Jørgen

2013-01-01

This chapter provides an introduction to and overview of peptide chemistry with a focus on solid-phase peptide synthesis. The background, the most common reagents, and some mechanisms are presented. This chapter also points to the different chapters and puts them into perspective.......This chapter provides an introduction to and overview of peptide chemistry with a focus on solid-phase peptide synthesis. The background, the most common reagents, and some mechanisms are presented. This chapter also points to the different chapters and puts them into perspective....

Taylor Dispersion Analysis as a promising tool for assessment of peptide-peptide interactions

DEFF Research Database (Denmark)

Høgstedt, Ulrich B; Schwach, Grégoire; van de Weert, Marco

2016-01-01

solutions increased with concentration. Our results indicate that a viscosity difference between run buffer and sample in Taylor Dispersion Analysis may result in overestimation of the measured diffusion coefficient. Thus, Taylor Dispersion Analysis provides a practical, but as yet primarily qualitative......Protein-protein and peptide-peptide (self-)interactions are of key importance in understanding the physiochemical behavior of proteins and peptides in solution. However, due to the small size of peptide molecules, characterization of these interactions is more challenging than for proteins...

Aggregation and toxicity of amyloid-beta peptide in relation to peptide sequence variation

OpenAIRE

Vandersteen, A.

2012-01-01

Generally, aggregation of the amyloid-ß peptide is considered the cause of neuronal death in Alzheimer disease. The heterogenous Aß peptide occurs in various lengths in vivo: Aß40 and Aß42 are the predominant forms while both shorter and longer peptides exist. Aß40 and shorter isoforms are less aggregation-prone and hence considered less dangerous than Aß42 and longer isoforms, which are more aggregation-prone. Up to now research mainly focussed on the predominant Aß peptides and their indivi...

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.

Development of a group contribution method for estimating free energy of peptides in a dodecane-water system via molecular dynamic simulations.

Science.gov (United States)

Mora Osorio, Camilo Andrés; González Barrios, Andrés Fernando

2016-12-07

Calculation of the Gibbs free energy changes of biological molecules at the oil-water interface is commonly performed with Molecular Dynamics simulations (MD). It is a process that could be performed repeatedly in order to find some molecules of high stability in this medium. Here, an alternative method of calculation has been proposed: a group contribution method (GCM) for peptides based on MD of the twenty classic amino acids to obtain free energy change during the insertion of any peptide chain in water-dodecane interfaces. Multiple MD of the twenty classic amino acids located at the interface of rectangular simulation boxes with a dodecane-water medium were performed. A GCM to calculate the free energy of entire peptides is then proposed. The method uses the summation of the Gibbs free energy of each amino acid adjusted in function of its presence or absence in the chain as well as its hydrophobic characteristics. Validation of the equation was performed with twenty-one peptides all simulated using MD in dodecane-water rectangular boxes in previous work, obtaining an average relative error of 16%.

A cocoa peptide protects Caenorhabditis elegans from oxidative stress and β-amyloid peptide toxicity.

Directory of Open Access Journals (Sweden)

Patricia Martorell

Full Text Available BACKGROUND: Cocoa and cocoa-based products contain different compounds with beneficial properties for human health. Polyphenols are the most frequently studied, and display antioxidant properties. Moreover, protein content is a very interesting source of antioxidant bioactive peptides, which can be used therapeutically for the prevention of age-related diseases. METHODOLOGY/PRINCIPAL FINDINGS: A bioactive peptide, 13L (DNYDNSAGKWWVT, was obtained from a hydrolyzed cocoa by-product by chromatography. The in vitro inhibition of prolyl endopeptidase (PEP was used as screening method to select the suitable fraction for peptide identification. Functional analysis of 13L peptide was achieved using the transgenic Caenorhabditis elegans strain CL4176 expressing the human Aβ₁₋₄₂ peptide as a pre-clinical in vivo model for Alzheimer's disease. Among the peptides isolated, peptide 13L (1 µg/mL showed the highest antioxidant activity (P≤0.001 in the wild-type strain (N2. Furthermore, 13L produced a significant delay in body paralysis in strain CL4176, especially in the 24-47 h period after Aβ₁₋₄₂ peptide induction (P≤0.0001. This observation is in accordance with the reduction of Aβ deposits in CL4176 by western blot. Finally, transcriptomic analysis in wild-type nematodes treated with 13L revealed modulation of the proteosomal and synaptic functions as the main metabolic targets of the peptide. CONCLUSIONS/SIGNIFICANCE: These findings suggest that the cocoa 13L peptide has antioxidant activity and may reduce Aβ deposition in a C. elegans model of Alzheimer's disease; and therefore has a putative therapeutic potential for prevention of age-related diseases. Further studies in murine models and humans will be essential to analyze the effectiveness of the 13L peptide in higher animals.

Radiolabelled peptides for oncological diagnosis

Energy Technology Data Exchange (ETDEWEB)

Laverman, Peter; Boerman, Otto C.; Oyen, Wim J.G. [Radboud University Nijmegen Medical Centre, Department of Nuclear Medicine, Nijmegen (Netherlands); Sosabowski, Jane K. [Queen Mary University of London, Centre for Molecular Oncology, Barts Cancer Institute, London (United Kingdom)

2012-02-15

Radiolabelled receptor-binding peptides targeting receptors (over)expressed on tumour cells are widely under investigation for tumour diagnosis and therapy. The concept of using radiolabelled receptor-binding peptides to target receptor-expressing tissues in vivo has stimulated a large body of research in nuclear medicine. The {sup 111}In-labelled somatostatin analogue octreotide (OctreoScan trademark) is the most successful radiopeptide for tumour imaging, and was the first to be approved for diagnostic use. Based on the success of these studies, other receptor-targeting peptides such as cholecystokinin/gastrin analogues, glucagon-like peptide-1, bombesin (BN), chemokine receptor CXCR4 targeting peptides, and RGD peptides are currently under development or undergoing clinical trials. In this review, we discuss some of these peptides and their analogues, with regard to their potential for radionuclide imaging of tumours. (orig.)

Peptide Vaccines for Leishmaniasis

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Rory C. F. De Brito

2018-05-01

Full Text Available Due to an increase in the incidence of leishmaniases worldwide, the development of new strategies such as prophylactic vaccines to prevent infection and decrease the disease have become a high priority. Classic vaccines against leishmaniases were based on live or attenuated parasites or their subunits. Nevertheless, the use of whole parasite or their subunits for vaccine production has numerous disadvantages. Therefore, the use of Leishmania peptides to design more specific vaccines against leishmaniases seems promising. Moreover, peptides have several benefits in comparison with other kinds of antigens, for instance, good stability, absence of potentially damaging materials, antigen low complexity, and low-cost to scale up. By contrast, peptides are poor immunogenic alone, and they need to be delivered correctly. In this context, several approaches described in this review are useful to solve these drawbacks. Approaches, such as, peptides in combination with potent adjuvants, cellular vaccinations, adenovirus, polyepitopes, or DNA vaccines have been used to develop peptide-based vaccines. Recent advancements in peptide vaccine design, chimeric, or polypeptide vaccines and nanovaccines based on particles attached or formulated with antigenic components or peptides have been increasingly employed to drive a specific immune response. In this review, we briefly summarize the old, current, and future stands on peptide-based vaccines, describing the disadvantages and benefits associated with them. We also propose possible approaches to overcome the related weaknesses of synthetic vaccines and suggest future guidelines for their development.

Peptide Vaccines for Leishmaniasis.

Science.gov (United States)

De Brito, Rory C F; Cardoso, Jamille M De O; Reis, Levi E S; Vieira, Joao F; Mathias, Fernando A S; Roatt, Bruno M; Aguiar-Soares, Rodrigo Dian D O; Ruiz, Jeronimo C; Resende, Daniela de M; Reis, Alexandre B

2018-01-01

Due to an increase in the incidence of leishmaniases worldwide, the development of new strategies such as prophylactic vaccines to prevent infection and decrease the disease have become a high priority. Classic vaccines against leishmaniases were based on live or attenuated parasites or their subunits. Nevertheless, the use of whole parasite or their subunits for vaccine production has numerous disadvantages. Therefore, the use of Leishmania peptides to design more specific vaccines against leishmaniases seems promising. Moreover, peptides have several benefits in comparison with other kinds of antigens, for instance, good stability, absence of potentially damaging materials, antigen low complexity, and low-cost to scale up. By contrast, peptides are poor immunogenic alone, and they need to be delivered correctly. In this context, several approaches described in this review are useful to solve these drawbacks. Approaches, such as, peptides in combination with potent adjuvants, cellular vaccinations, adenovirus, polyepitopes, or DNA vaccines have been used to develop peptide-based vaccines. Recent advancements in peptide vaccine design, chimeric, or polypeptide vaccines and nanovaccines based on particles attached or formulated with antigenic components or peptides have been increasingly employed to drive a specific immune response. In this review, we briefly summarize the old, current, and future stands on peptide-based vaccines, describing the disadvantages and benefits associated with them. We also propose possible approaches to overcome the related weaknesses of synthetic vaccines and suggest future guidelines for their development.

Fasting plasma C-peptide, glucagon stimulated plasma C-peptide, and urinary C-peptide in relation to clinical type of diabetes

DEFF Research Database (Denmark)

Gjessing, H J; Matzen, L E; Faber, O K

1989-01-01

with a fasting plasma C-peptide value less than 0.20 nmol/l, a glucagon stimulated plasma C-peptide value less than 0.32 nmol/l, and a urinary C-peptide value less than 3.1 nmol/l, or less than 0.54 nmol/mmol creatinine/24 h, or less than 5.4 nmol/24 h mainly were Type 1 diabetic patients; while patients with C...

A LEI DE CRIMES AMBIENTAIS E ANÁLISE DA EFETIVIDADE JURÍDICO-ECONÔMICA A PARTIR DE MODELOS ECONOMÉTRICOS

Directory of Open Access Journals (Sweden)

Dacicleide Souza Cunha

2014-04-01

Full Text Available A pesquisa tem como objetivo estudar a efetividade da Lei de Crimes Ambientais (9.605/98 aplicada a crimes contra a flora no estado do Amapá no período entre 2000 e 2008. A metodologia do estudo consistiu nas seguintes etapas: a obtenção de dados sobre os Autos de Infração contra a flora (banco de dados do IBAMA-AP, b análise da cobrança cível, c análise da impetração de ação criminal pelos Ministérios Públicos Estadual e Federal e d verificação de etapas de procedimentos e conclusão dos processos cíveis e criminais, utilizando probabilidades de sucesso e insucesso. Como resultado foram desenvolvidos dois modelos conceituais econométricos, um cívil e um criminal, ambos aplicados na análise da efetividade da Lei a partir de cenários jurídico-econômicos. Parâmetros econométricos, como montante da multa, taxa de juros (%a.m e período de aplicação da multa foram utilizados nos modelos, bem como probabilidades observacionais relacionadas com o nível de sucesso de cada etapa dos processos cívis e criminais. Os resultados da aplicação dos modelos econométricos propostos representam razoavelmente bem os riscos de efetividade da Lei, com base em números de autuações, condenações penais e pagamento das multas cíveis. Por esta perspectiva, os instrumentos administrativos e criminais mostraram reduzida efetividade, com poucas condenações, provavelmente incrementada pela complexidade jurídica do setor no sistema brasileiro. Conclui-se que há falhas consideráveis no cumprimento de procedimentos administrativos e judiciais, mas que podem ser relativamente bem explicadas pelos modelos econométricos propostos. Palavras-chave: Amazônia Oriental, Lei de Crimes Ambientais, efetividade, modelo matemático. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v4n1p50-64

Evaluation of social disablement, psychiatric symptoms and autonomy in long-stay psychiatric patients Avaliação do comportamento social, sintomas psiquiátricos e autonomia em pacientes psiquiátricos de longa permanência

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Lúcia Abelha

2006-01-01

Full Text Available BACKGROUND: Data on prevalence of social disablement, psychiatric symptoms and independent living skills in long-stay psychiatric patients are scarce in Brazil. Therefore, a cross-sectional study was carried out on a population of 881 long-stay psychiatric patients. METHOD: Data were collected from all the patients living in the Municipal Mental Health Institute from Rio de Janeiro city, using 3 instruments: Social Behaviour Schedule (SBS-BR, Brief Psychiatric Rating Scale (BPRS, and Independent Living Skills Survey (ILSS-BR. RESULTS: 75% of total patients presented poor independent living skills, and high rates of social disablement, specially in the items: poor self care (50,9%, little spontaneous communication (46,2% and underactivity (37,5%. 15.1% of schizophrenic patients showed severe symptoms of hallucinations, delusions and conceptual disorganization.11.5% did not present psychiatric symptoms in the last month, and 16% showed no social disablement CONCLUSION: 50% of patients are older than 65 years and have been living in the institution for more than 38 years. They present high rates of problem behaviours and poor autonomy. Our data should suggest the adoption of treatment programs or interventions for those patients. Also, there is a group without psychiatric symptoms, good autonomy degree and no social disablement that could live in therapeutic residences in the community.INTRODUÇÃO: No Brasil ainda são escassos os dados sobre limitações no comportamento social, sintomas psiquiátricos e habilidades de vida independente. Nesse sentido foi realizado um estudo seccional em uma população de 881 pacientes psiquiátricos de longa permanência. METODOLOGIA: Foram coletados dados de todos os pacientes residentes no Instituto Municipal Juliano Moreira, utilizando três instrumentos: Avaliação das Limitações no Comportamento Social (SBS-BR, Brief Psychiatric Rating Scale (BPRS e o Inventário de Habilidades de Vida Independente para

PH dependent adhesive peptides

Science.gov (United States)

Tomich, John; Iwamoto, Takeo; Shen, Xinchun; Sun, Xiuzhi Susan

2010-06-29

A novel peptide adhesive motif is described that requires no receptor or cross-links to achieve maximal adhesive strength. Several peptides with different degrees of adhesive strength have been designed and synthesized using solid phase chemistries. All peptides contain a common hydrophobic core sequence flanked by positively or negatively charged amino acids sequences.

O perfil dos cuidadores de pacientes pediátricos com fibrose cística

OpenAIRE

Alves, Stella Pegoraro; Bueno, Denise

2018-01-01

Resumo O objetivo desse estudo foi identificar o perfil do cuidador principal de pacientes pediátricos com Fibrose Cística (FC). Estudo transversal, descritivo e prospectivo, no qual foi realizado, durante consulta farmacêutica, entrevista com cuidadores de pacientes fibrocísticos acompanhados em um centro de referência de um Hospital Universitário do Sul do Brasil. Foram obtidas informações gerais sobre os cuidadores, sobre o entendimento da doença, os medicamentos em uso do paciente e a din...

Virtual screening using combinatorial cyclic peptide libraries reveals protein interfaces readily targetable by cyclic peptides.

Science.gov (United States)

Duffy, Fergal J; O'Donovan, Darragh; Devocelle, Marc; Moran, Niamh; O'Connell, David J; Shields, Denis C

2015-03-23

Protein-protein and protein-peptide interactions are responsible for the vast majority of biological functions in vivo, but targeting these interactions with small molecules has historically been difficult. What is required are efficient combined computational and experimental screening methods to choose among a number of potential protein interfaces worthy of targeting lead macrocyclic compounds for further investigation. To achieve this, we have generated combinatorial 3D virtual libraries of short disulfide-bonded peptides and compared them to pharmacophore models of important protein-protein and protein-peptide structures, including short linear motifs (SLiMs), protein-binding peptides, and turn structures at protein-protein interfaces, built from 3D models available in the Protein Data Bank. We prepared a total of 372 reference pharmacophores, which were matched against 108,659 multiconformer cyclic peptides. After normalization to exclude nonspecific cyclic peptides, the top hits notably are enriched for mimetics of turn structures, including a turn at the interaction surface of human α thrombin, and also feature several protein-binding peptides. The top cyclic peptide hits also cover the critical "hot spot" interaction sites predicted from the interaction crystal structure. We have validated our method by testing cyclic peptides predicted to inhibit thrombin, a key protein in the blood coagulation pathway of important therapeutic interest, identifying a cyclic peptide inhibitor with lead-like activity. We conclude that protein interfaces most readily targetable by cyclic peptides and related macrocyclic drugs may be identified computationally among a set of candidate interfaces, accelerating the choice of interfaces against which lead compounds may be screened.

Indicadores antropométricos como preditores de pressão arterial elevada em adolescentes Indicadores antropométricos como predictores de presión arterial elevada en adolescentes Anthropometric indicators as predictors of high blood pressure in adolescents

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Carmem Cristina Beck

2011-02-01

Full Text Available FUNDAMENTO: A hipertensão arterial está relacionada ao incremento da gordura corporal, a qual pode ser avaliada por meio de indicadores antropométricos. OBJETIVO: Determinar o poder preditivo de indicadores antropométricos e estabelecer seus pontos de corte como discriminadores de pressão arterial elevada. MÉTODOS: Estudo transversal realizado com uma amostra de 660 adolescentes de 14 a 19 anos sendo 51,9% moças. Foram considerados os seguintes indicadores antropométricos: índice de massa corporal (IMC, circunferência da cintura, razão cintura/estatura e índice de conicidade. A pressão arterial elevada foi caracterizada por valores acima do percentil 90 para pressão arterial sistólica e/ou pressão arterial diastólica. Para identificação dos preditores de pressão arterial elevada, foi adotada a análise das curvas Receiver Operating Characteristic (ROC, com intervalo de confiança de 95%. Posteriormente, identificaram-se os pontos de corte com suas respectivas sensibilidades e especificidades. RESULTADOS: As áreas sob as curvas ROC com os intervalos de confiança foram: rapazes - circunferência de cintura = 0,80 (0,72-0,89; IMC = 0,79 (0,68-0,89; razão cintura/estatura = 0,77 (0,66-0,88; índice de conicidade = 0,69 (0,56-0,81 e para as moças - circunferência de cintura = 0,96 (0,92-1,00; IMC = 0,95 (0,87-1,00; razão cintura/estatura = 0,93 (0,85-1,00; índice de conicidade = 0,74 (0,50-0,98. Os diversos pontos de corte dos indicadores antropométricos com melhores poderes preditivos e suas respectivas sensibilidades e especificidades foram identificados. CONCLUSÃO: Apesar de a razão cintura/estatura e de o IMC terem apresentado boas áreas sob a curva ROC, sugere-se a utilização da circunferência de cintura para a predição da pressão arterial elevada.FUNDAMENTO: La hipertensión arterial está relacionada al incremento de la grasa corporal, a la que se puede evaluar por medio de indicadores antropométricos

Zinc (II) [tetra(4-methylphenyl)] Porphyrin: a Novel and Reusable Catalyst for Efficient Synthesis of 2,4,5-trisubstituted Imidazoles Under Ultrasound Irradiation

Energy Technology Data Exchange (ETDEWEB)

Safari, Javad; Khalili, Shiva Dehghan; Banitaba, Sayed Hossein; Dehghani, Hossein [Univ. of Kashan, Kashan (Iran, Islamic Republic of)

2011-10-15

An efficient three-component one-step synthesis of 2,4,5-trisubstituted imidazoles by condensation reaction of 1,2-diketones or α-hydroxyketones with aromatic aldehydes and ammonium acetate using Zinc (II) [tetra (4-methylphenyl)] porphyrin as a novel and reusable catalyst under ultrasound irradiation at ambient temperature is described. In this method, α-hydroxyketones as well as 1,2-diketones were converted to their corresponding 2,4,5-trisubstituted imidazoles in excellent yields.

Versatile supramolecular reactivity of zinc-tetra(4-pyridylporphyrin in crystalline solids: Polymeric grids with zinc dichloride and hydrogen-bonded networks with mellitic acid

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Sophia Lipstman

2009-12-01

Full Text Available Crystal engineering studies confirm that the zinc-tetra(4-pyridylporphyrin building block reveals versatile supramolecular chemistry. In this work, it was found to be reactive in the assembly of both (a a 2D polymeric array by a unique combination of self-coordination and coordination through external zinc dichloride linkers and (b an extended heteromolecular hydrogen-bonded network with mellitic acid sustained by multiple connectivity between the component species.

The non-peptidic part determines the internalization mechanism and intracellular trafficking of peptide amphiphiles.

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Dimitris Missirlis

Full Text Available BACKGROUND: Peptide amphiphiles (PAs are a class of amphiphilic molecules able to self-assemble into nanomaterials that have shown efficient in vivo targeted delivery. Understanding the interactions of PAs with cells and the mechanisms of their internalization and intracellular trafficking is critical in their further development for therapeutic delivery applications. METHODOLOGY/PRINCIPAL FINDINGS: PAs of a novel, cell- and tissue-penetrating peptide were synthesized possessing two different lipophilic tail architectures and their interactions with prostate cancer cells were studied in vitro. Cell uptake of peptides was greatly enhanced post-modification. Internalization occurred via lipid-raft mediated endocytosis and was common for the two analogs studied. On the contrary, we identified the non-peptidic part as the determining factor of differences between intracellular trafficking and retention of PAs. PAs composed of di-stearyl lipid tails linked through poly(ethylene glycol to the peptide exhibited higher exocytosis rates and employed different recycling pathways compared to ones consisting of di-palmitic-coupled peptides. As a result, cell association of the former PAs decreased with time. CONCLUSIONS/SIGNIFICANCE: Control over peptide intracellular localization and retention is possible by appropriate modification with synthetic hydrophobic tails. We propose this as a strategy to design improved peptide-based delivery systems.

Manejo obstétrico de la deficiencia hereditaria de antitrombina durante el embarazo y puerperio. Dos casos clínicos

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Milagros Cruz Martínez

2015-12-01

Full Text Available Resumen Introducción: la deficiencia de antitrombina III hereditaria es una rara enfermedad que afecta al 0.02-0.2% de la población. Puede presentar mayor frecuencia de complicaciones y resultados adversos tanto en la madre como en el feto. Se presenta el manejo obstétrico de dos gestaciones consecutivas en una mujer con deficiencia de antitrombina III. Descripción: en ambos embarazos la madre realiza profilaxis de la enfermedad tromboembólica con heparina de bajo peso molecular para evitar la aparición de esta patología tanto en el embarazo como en el puerperio y mejorar el flujo útero-placen-tario. Con respecto a las complicaciones obstétricas, sólo existe un enlentecimiento del crecimiento fetal que obliga a un control obstétrico estricto. En ambas gestaciones los estudios eco-Doppler están dentro de la normalidad lo que permite una conducta expectante, consiguiendo llegar a término. Discusión: la profilaxis con heparina de bajo peso molecular en las gestantes con esta trombofilia y las intervenciones preventivas de factores de riesgo de enfermedad tromboembólica, junto con un control obstétrico adecuado, ha conseguido evitar la apari-ción de complicaciones derivadas de esta patología en el embarazo y en el puerperio. Por otra parte, el control del crecimiento fetal y el estudio Eco-Doppler han permitido asegurar el bienestar fetal no adelan-tando el parto, consiguiendo partos a término.

Correlación entre la autoestima de la madre y las puntuaciones en el cuestionario de síntomas pediátricos

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Adalberto Campo-Arias,

2008-04-01

Full Text Available Contexto: Posiblemente una pobre autoevaluación(autoestima de la madre pueda sobre o subestimarsíntomas en el hijo evaluado. Sin embargo, no hay estudiosque exploren esta asociación. Objetivo: Conocer lacorrelación entre las puntuaciones de las cuatro subescalasdel cuestionario de Jellinek para síntomas pediátricos y lapuntuación en la escala de Rosenberg para autoestima enmadres de niños y niñas escolares de Cartagena, Colombia.Método: Se diseñó un estudio transversal en el que lasmadres diligenciaron las subescalas del cuestionario deJellinek para síntomas pediátricos (síntomas de desatencióne hiperactividad, depresivos, conductuales y ansiosos y laescala de Rosenberg para autoestima. Se determinó lacorrelación entre las subescalas del cuestionario de Jellinekpara síntomas pediátricos y la escala de Rosenberg paraautoestima (versión dicotómica con el coeficiente dePearson (r. Se aceptaron como significativas r<0,30 yvalores de p<0,01. Resultados: Participaron 190 madres(edad promedio= 34,4 años; DE=7,4 de niñas y niños entre6 y 10 años (promedio=7,6, DE=1,4 y escolaridad promediode 2,9 (DE=1,3. La correlación entre la puntuación parasíntomas de desatención e hiperactividad fue 0,130(p=0,077; para síntomas depresivos, -0,213 (p=0,003; parasíntomas conductuales, -0.103 (p=0,159; y para síntomasansiosos, -0,112 (p=0,125 y la puntuación en la escala deRosenberg para autoestima. Conclusiones: Laspuntuaciones en las subescalas del cuestionario de Jellinekpara síntomas pediátricos no guardan correlaciónclínicamente importante con las puntuaciones de la madre Campoenla escala de Rosenberg para autoestima.

Inimputabilidade: estudo dos internos do Instituto Psiquiátrico Forense Maurício Cardoso Nonimputability: a study on inmates at Instituto Psiquiátrico Forense Maurício Cardoso

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Gabriel Jose Chittó Gauer

2007-12-01

Full Text Available INTRODUÇÃO: A pesquisa traçou um perfil dos internos inimputáveis do Instituto Psiquiátrico Forense Maurício Cardoso. MÉTODOS: Durante o período de abril a agosto de 2005, foram selecionados 617 sujeitos para inclusão no estudo. RESULTADOS: A análise dos dados revelou que os internos apresentam as seguintes características: idade média de 43,22 anos, sexo masculino (91,3%, profissão definida (73,2%, primeiro grau completo (74,6%, sem companheiro(a (83,2%, crime contra a pessoa como delito gerador da inimputabilidade (62,1%, com antecedentes criminais (58,3%, prazo mínimo fixado na sentença de 1,76 anos, cumprindo medida de segurança detentiva (91,4%, média do tempo de internação de 9,33 anos, sob o regime de alta progressiva (81,5%, com internação prévia em outras instituições psiquiátricas (55,2%, sem cumprimento anterior de medida de segurança (83,3%, com o diagnóstico de esquizofrenia e outros transtornos psicóticos (61,4%. Os cruzamentos de variáveis que tiveram relevância estatística foram: dos internos com internação prévia, 61,9% possuíam antecedentes criminais, e quanto maior o nível de escolaridade do interno, menor o índice de reincidência. Evidenciou-se uma preponderância de internos com antecedentes criminais em pacientes com transtornos relacionados a substâncias (56,5% e transtorno de personalidade (59,7%. Verificou-se que 60,8% daqueles que cometeram crimes contra a pessoa possuíam diagnóstico de transtornos relacionados ao álcool, estabelecendo uma relação entre criminalidade violenta e os transtornos de uso de substâncias. CONCLUSÕES: A partir da análise dos prontuários dos 617 internos do Instituto Psiquiátrico Forense Maurício Cardoso, o presente estudo procurou apresentar um mapa dos indivíduos considerados inimputáveis no Rio Grande do Sul.INTRODUCTION: This study analyzed the profile of nonimputable inmates at Instituto Psiquiátrico Forense Maurício Cardoso. METHODS

Motor elétrico de indução: “uma das dez maiores invenções de todos os tempos”

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Fernando Lang da Silveira

2012-04-01

Full Text Available http://dx.doi.org/10.5007/2175-7941.2012v29n1p114 O objetivo deste trabalho é apresentar dois projetos de motores elétricos de indução efetiváveis em um laboratório de ensino de eletromagnetismo. O motor elétrico de indução, cuja patente original é de Nikola Tesla (1888 surpreendentemente está ausente dos livros de física geral de ensino médio ou superior e também não é encontrado usualmente em laboratórios de ensino de física. Além da inegável importância de tal tipo de motor no cotidiano, seja nos eletrodomésticos, seja como máquinas de alta potência, ele ilustra belamente a Lei de Faraday-Lenz.

Expression of the cationic antimicrobial peptide lactoferricin fused with the anionic peptide in Escherichia coli.

Science.gov (United States)

Kim, Ha-Kun; Chun, Dae-Sik; Kim, Joon-Sik; Yun, Cheol-Ho; Lee, Ju-Hoon; Hong, Soon-Kwang; Kang, Dae-Kyung

2006-09-01

Direct expression of lactoferricin, an antimicrobial peptide, is lethal to Escherichia coli. For the efficient production of lactoferricin in E. coli, we developed an expression system in which the gene for the lysine- and arginine-rich cationic lactoferricin was fused to an anionic peptide gene to neutralize the basic property of lactoferricin, and successfully overexpressed the concatemeric fusion gene in E. coli. The lactoferricin gene was linked to a modified magainin intervening sequence gene by a recombinational polymerase chain reaction, thus producing an acidic peptide-lactoferricin fusion gene. The monomeric acidic peptide-lactoferricin fusion gene was multimerized and expressed in E. coli BL21(DE3) upon induction with isopropyl-beta-D-thiogalactopyranoside. The expression levels of the fusion peptide reached the maximum at the tetramer, while further increases in the copy number of the fusion gene substantially reduced the peptide expression level. The fusion peptides were isolated and cleaved to generate the separate lactoferricin and acidic peptide. About 60 mg of pure recombinant lactoferricin was obtained from 1 L of E. coli culture. The purified recombinant lactoferricin was found to have a molecular weight similar to that of chemically synthesized lactoferricin. The recombinant lactoferricin showed antimicrobial activity and disrupted bacterial membrane permeability, as the native lactoferricin peptide does.

Synthesis of peptide .alpha.-thioesters

Science.gov (United States)

Camarero, Julio A [Livermore, CA; Mitchell, Alexander R [Livermore, CA; De Yoreo, James J [Clayton, CA

2008-08-19

Disclosed herein is a new method for the solid phase peptide synthesis (SPPS) of C-terminal peptide .alpha. thioesters using Fmoc/t-Bu chemistry. This method is based on the use of an aryl hydrazine linker, which is totally stable to conditions required for Fmoc-SPPS. When the peptide synthesis has been completed, activation of the linker is achieved by mild oxidation. The oxidation step converts the acyl-hydrazine group into a highly reactive acyl-diazene intermediate which reacts with an .alpha.-amino acid alkylthioester (H-AA-SR) to yield the corresponding peptide .alpha.-thioester in good yield. A variety of peptide thioesters, cyclic peptides and a fully functional Src homology 3 (SH3) protein domain have been successfully prepared.

Levantamientos y seguimientos topo-batimétricos en ingeniería de costas

OpenAIRE

Esteban Chapapría, Vicent; Aguilar, José; Serra Peris, José; Medina, Josep R.

1995-01-01

Se describen los métodos de ejecución de trabajos topográficos y batimétricos de seguimiento de playas, esenciales para la comprensión y control de los procesos litorales. Se plantea el problema de la medición de profundidades y de otras variables descriptivas de la fenomenología oceánica y las fuentes de error dependiendo de las técnicas y métodos empleados. Se comparan los errores de medida típicos de los sistemas de medición de profundidades habituales señalando los niveles de error ...

Circuito elétrico auxiliar para intubação das vias lacrimais

OpenAIRE

Fernandes,José Byron Vicente Dias; Matayoshi,Suzana; Komatsu,Wilson; Kikuta,Henrique S.; Moura,Eurípedes da Mota

2000-01-01

Objetivo: Apresentam num circuito elétrico auxiliar para a intubação de vias lacrimais. Método: Descreve-se o dispositivo e sua utilização em 40 pacientes com obstrução congênita ou traumática das vias lacrimais. Resultados: O estudo das características elétricas do aparelho mostrou suas vantagens em relação a outros dispositivos citados na literatura. O uso do aparelho facilitou a recuperação das sondas de Crawford em todos os pacientes. Conclusão: O CAI mostrou-se eficiente e seguro sendo q...

Prevalência de transtornos psiquiátricos em portadores de prótese valvar mecânica com e sem febre reumática

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Regina Ponce da Silva

2011-01-01

Full Text Available OBJETIVO: Valvulopatias cardíacas, causadas por febre reumática e outras etiologias, podem levar ao implante de prótese valvar mecânica e anticoagulação oral obrigatória. Comorbidade psiquiátrica pode reduzir a adesão à anticoagulação. Esse estudo teve como objetivo avaliar a prevalência de transtornos psiquiátricos em pacientes com prótese valvar mecânica. MÉTODOS: Foram avaliados 193 portadores de prótese valvar mecânica, sendo 135 com cardiopatia reumática, tendo sido utilizada a Mini International Neuropsychiatric Interview, versão 5.0.0, para investigação quanto à presença de transtornos psiquiátricos. RESULTADOS: Foram encontrados os seguintes transtornos psiquiátricos nos pacientes avaliados: transtornos de ansiedade generalizada (16,6%, agorafobia (11,9%, fobia social (10,4%, depressão (9,8%, distimia (4,1% atual e 1% no passado, transtorno obsessivo-compulsivo (3,6%, pânico - vida inteira (1,6%, dependência ou abuso de substâncias (2%, dependência ou abuso de álcool (1%, episódio hipomaníaco (0,5% atual e 0,5% no passado, bulimia (0,5%. O risco de suicídio detectado foi de 13,4%. Ao ser comparada a prevalência dos transtornos no grupo com e sem cardiopatia reumática, não foi encontrada diferença estatisticamente significativa. CONCLUSÃO: Foi encontrada elevada comorbidade de transtornos psiquiátricos, principalmente transtornos ansiosos e depressão, sendo também elevado o risco de suicídio nessa população.

Calidad de la atención nutricional en el paciente pediátrico hospitalizado

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Yuri Betancourt Guerra

2012-09-01

Full Text Available Introducción: la nutrición es un aspecto importante en la terapéutica actual de los pacientes y tiene una repercusión social, por lo que todo el personal de salud debe considerarlo como un pilar terapéutico a la hora de atender a un enfermo. Objetivo: evaluar la calidad de la atención nutricional del paciente pediátrico hospitalizado. Métodos: se realizó un estudio descriptivo transversal, y la muestra estuvo constituida por 50 pacientes. Se confeccionó un Formulario de Atención Nutricional que sirvió para registrar el estado actual del apoyo nutricional, y de esta forma, se evaluó la calidad de su atención. Resultados: la evaluación nutricional, al momento del ingreso, fue solo de un 18 %, y el diagnóstico del estado nutricional no se realizó en el 96 % de los pacientes ingresados. La realización de exámenes de laboratorio con relevancia nutricional fue de un 12 %, mientras las acciones terapéuticas para corregir los exámenes patológicos fueron de un 50 %. No se daba seguimiento a la curva de peso, y todos los pacientes ingresados mantenían regímenes de ayuno hospitalario por encima del 10 %. Conclusiones: la calidad de la atención nutricional en el paciente pediátrico hospitalizado fue deficiente.

Peptides in melanoma therapy.

Science.gov (United States)

Mocellin, Simone

2012-01-01

Peptides derived from tumor associated antigens can be utilized to elicit a therapeutically effective immune response against melanoma in experimental models. However, patient vaccination with peptides - although it is often followed by the induction of melanoma- specific T lymphocytes - is rarely associated with tumor response of clinical relevance. In this review I summarize the principles of peptide design as well as the results so far obtained in the clinical setting while treating cutaneous melanoma by means of this active immunotherapy strategy. I also discuss some immunological and methodological issues that might be helpful for the successful development of peptide-based vaccines.

Escala de Estrés Percibido-10: Desempeño psicométrico en estudiantes de medicina de Bucaramanga, Colombia

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Adalberto Campo-Arias

2014-07-01

Conclusiones: EEP-10 baja consistencia interna y dos dimensiones que se comportan como escalas independientes con alta consistencia interna. Se necesita conocer el desempeño psicométrico de este instrumento de medición en salud en estudiantes universitarios colombianos de otras carreras.

Structural Basis of Rap Phosphatase Inhibition by Phr Peptides

Science.gov (United States)

Gallego del Sol, Francisca; Marina, Alberto

2013-01-01

Two-component systems, composed of a sensor histidine kinase and an effector response regulator (RR), are the main signal transduction devices in bacteria. In Bacillus, the Rap protein family modulates complex signaling processes mediated by two-component systems, such as competence, sporulation, or biofilm formation, by inhibiting the RR components involved in these pathways. Despite the high degree of sequence homology, Rap proteins exert their activity by two completely different mechanisms of action: inducing RR dephosphorylation or blocking RR binding to its target promoter. However the regulatory mechanism involving Rap proteins is even more complex since Rap activity is antagonized by specific signaling peptides (Phr) through a mechanism that remains unknown at the molecular level. Using X-ray analyses, we determined the structure of RapF, the anti-activator of competence RR ComA, alone and in complex with its regulatory peptide PhrF. The structural and functional data presented herein reveal that peptide PhrF blocks the RapF-ComA interaction through an allosteric mechanism. PhrF accommodates in the C-terminal tetratricopeptide repeat domain of RapF by inducing its constriction, a conformational change propagated by a pronounced rotation to the N-terminal ComA-binding domain. This movement partially disrupts the ComA binding site by triggering the ComA disassociation, whose interaction with RapF is also sterically impaired in the PhrF-induced conformation of RapF. Sequence analyses of the Rap proteins, guided by the RapF-PhrF structure, unveil the molecular basis of Phr recognition and discrimination, allowing us to relax the Phr specificity of RapF by a single residue change. PMID:23526880

Estudio fotométrico de estrellas tardías de alta luminosidad en 23 cúmulos abiertos

Science.gov (United States)

Clariá, J. J.; Piatti, A. E.; Osborn, W.

Se presentan resultados obtenidos en los Observatorios de Cerro Tololo, Kitt Peak, Lowell y Las Campanas, a partir de fotometría UBV y DDO de 54 estrellas tardías de alta luminosidad en 23 cúmulos abiertos. La aplicación de dos criterios fotométricos independientes permite asignar a cada estrella probabilidades de pertenencia a cada agregado. Se encuentra que 32 estrellas son muy probablemente miembros de los cúmulos, mientras que las restantes son objetos del campo. En todos los casos se determinan excesos de color E(B-V) a través de procedimientos fotométricos y espectroscópicos tradicionales. Recientes calibraciones del sistema DDO permiten, además, derivar tipos espectrales MK, temperaturas efectivas, y abundancias superficiales de la muestra examinada. Las metalicidades DDO derivadas se distribuyen entre valores típicos de cúmulos moderadamente pobres en metales ([Fe/H]~=-0.3) y moderadamente ricos ([Fe/H]~=0.2), en tanto que las masas calculadas para las gigantes rojas oscilan entre 1 y 4 masas solares, con una dispersión dentro de cada cúmulo menor que 1 Msolar.

[PdA (IPr*) (cinnamyl)Cl]: An efficient pre-catalyst for the preparation of tetra-ortho-substituted biaryls by Suzuki-Miyaura cross-coupling

KAUST Repository

Chartoire, Anthony

2012-03-13

The bigger the better: The new well-defined [Pd(IPr*)(cin)Cl] pre-catalyst is described (see scheme). This complex proves to be highly active in the Suzuki-Miyaura cross-coupling for the synthesis of tetra-ortho- substituted biaryls under mild conditions. IPr* is reported as the largest N-heterocyclic carbene (NHC) to date for [Pd(NHC)(cin)Cl] complexes, explaining the high reactivity observed for this complex in this challenging transformation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[PdA (IPr*) (cinnamyl)Cl]: An efficient pre-catalyst for the preparation of tetra-ortho-substituted biaryls by Suzuki-Miyaura cross-coupling

KAUST Repository

Chartoire, Anthony; Lesieur, Mathieu; Falivene, Laura; Slawin, Alexandra M. Z.; Cavallo, Luigi; Cazin, Catherine S J; Nolan, Steven P.

2012-01-01

The bigger the better: The new well-defined [Pd(IPr*)(cin)Cl] pre-catalyst is described (see scheme). This complex proves to be highly active in the Suzuki-Miyaura cross-coupling for the synthesis of tetra-ortho- substituted biaryls under mild conditions. IPr* is reported as the largest N-heterocyclic carbene (NHC) to date for [Pd(NHC)(cin)Cl] complexes, explaining the high reactivity observed for this complex in this challenging transformation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Computer-Aided Design of Antimicrobial Peptides

DEFF Research Database (Denmark)

Fjell, Christopher D.; Hancock, Robert E.W.; Jenssen, Håvard

2010-01-01

in antimicrobial activity. Consequently, the majority of peptides put into clinical trials have failed at some point, underlining the importance of a thorough peptide optimization. An important tool in peptide design and optimization is quantitative structure-activity relationship (QSAR) analysis, correlating...... chemical parameters with biological activities of the peptide, using statistical methods. In this review we will discuss two different in silico strategies of computer-aided antibacterial peptide design, a linear correlation model build as an extension of traditional principal component analysis (PCA......) and a non-linear artificial neural network model. Studies on structurally diverse peptides, have concluded that the PCA derived model are able to guide the antibacterial peptide design in a meaningful way, however requiring rather a high homology between the peptides in the test-set and the in silico...

Ligand-regulated peptides: a general approach for modulating protein-peptide interactions with small molecules.

Science.gov (United States)

Binkowski, Brock F; Miller, Russell A; Belshaw, Peter J

2005-07-01

We engineered a novel ligand-regulated peptide (LiRP) system where the binding activity of intracellular peptides is controlled by a cell-permeable small molecule. In the absence of ligand, peptides expressed as fusions in an FKBP-peptide-FRB-GST LiRP scaffold protein are free to interact with target proteins. In the presence of the ligand rapamycin, or the nonimmunosuppressive rapamycin derivative AP23102, the scaffold protein undergoes a conformational change that prevents the interaction of the peptide with the target protein. The modular design of the scaffold enables the creation of LiRPs through rational design or selection from combinatorial peptide libraries. Using these methods, we identified LiRPs that interact with three independent targets: retinoblastoma protein, c-Src, and the AMP-activated protein kinase. The LiRP system should provide a general method to temporally and spatially regulate protein function in cells and organisms.

Mycobacteria attenuate nociceptive responses by formyl peptide receptor triggered opioid peptide release from neutrophils.

Directory of Open Access Journals (Sweden)

Heike L Rittner

2009-04-01

Full Text Available In inflammation, pain is regulated by a balance of pro- and analgesic mediators. Analgesic mediators include opioid peptides which are secreted by neutrophils at the site of inflammation, leading to activation of opioid receptors on peripheral sensory neurons. In humans, local opioids and opioid peptides significantly downregulate postoperative as well as arthritic pain. In rats, inflammatory pain is induced by intraplantar injection of heat inactivated Mycobacterium butyricum, a component of complete Freund's adjuvant. We hypothesized that mycobacterially derived formyl peptide receptor (FPR and/or toll like receptor (TLR agonists could activate neutrophils, leading to opioid peptide release and inhibition of inflammatory pain. In complete Freund's adjuvant-induced inflammation, thermal and mechanical nociceptive thresholds of the paw were quantified (Hargreaves and Randall-Selitto methods, respectively. Withdrawal time to heat was decreased following systemic neutrophil depletion as well as local injection of opioid receptor antagonists or anti-opioid peptide (i.e. Met-enkephalin, beta-endorphin antibodies indicating an increase in pain. In vitro, opioid peptide release from human and rat neutrophils was measured by radioimmunoassay. Met-enkephalin release was triggered by Mycobacterium butyricum and formyl peptides but not by TLR-2 or TLR-4 agonists. Mycobacterium butyricum induced a rise in intracellular calcium as determined by FURA loading and calcium imaging. Opioid peptide release was blocked by intracellular calcium chelation as well as phosphoinositol-3-kinase inhibition. The FPR antagonists Boc-FLFLF and cyclosporine H reduced opioid peptide release in vitro and increased inflammatory pain in vivo while TLR 2/4 did not appear to be involved. In summary, mycobacteria activate FPR on neutrophils, resulting in tonic secretion of opioid peptides from neutrophils and in a decrease in inflammatory pain. Future therapeutic strategies may aim

Focused Screening of ECM-Selective Adhesion Peptides on Cellulose-Bound Peptide Microarrays.

Science.gov (United States)

Kanie, Kei; Kondo, Yuto; Owaki, Junki; Ikeda, Yurika; Narita, Yuji; Kato, Ryuji; Honda, Hiroyuki

2016-11-19

The coating of surfaces with bio-functional proteins is a promising strategy for the creation of highly biocompatible medical implants. Bio-functional proteins from the extracellular matrix (ECM) provide effective surface functions for controlling cellular behavior. We have previously screened bio-functional tripeptides for feasibility of mass production with the aim of identifying those that are medically useful, such as cell-selective peptides. In this work, we focused on the screening of tripeptides that selectively accumulate collagen type IV (Col IV), an ECM protein that accelerates the re-endothelialization of medical implants. A SPOT peptide microarray was selected for screening owing to its unique cellulose membrane platform, which can mimic fibrous scaffolds used in regenerative medicine. However, since the library size on the SPOT microarray was limited, physicochemical clustering was used to provide broader variation than that of random peptide selection. Using the custom focused microarray of 500 selected peptides, we assayed the relative binding rates of tripeptides to Col IV, collagen type I (Col I), and albumin. We discovered a cluster of Col IV-selective adhesion peptides that exhibit bio-safety with endothelial cells. The results from this study can be used to improve the screening of regeneration-enhancing peptides.

Focused Screening of ECM-Selective Adhesion Peptides on Cellulose-Bound Peptide Microarrays

Directory of Open Access Journals (Sweden)

Kei Kanie

2016-11-01

Full Text Available The coating of surfaces with bio-functional proteins is a promising strategy for the creation of highly biocompatible medical implants. Bio-functional proteins from the extracellular matrix (ECM provide effective surface functions for controlling cellular behavior. We have previously screened bio-functional tripeptides for feasibility of mass production with the aim of identifying those that are medically useful, such as cell-selective peptides. In this work, we focused on the screening of tripeptides that selectively accumulate collagen type IV (Col IV, an ECM protein that accelerates the re-endothelialization of medical implants. A SPOT peptide microarray was selected for screening owing to its unique cellulose membrane platform, which can mimic fibrous scaffolds used in regenerative medicine. However, since the library size on the SPOT microarray was limited, physicochemical clustering was used to provide broader variation than that of random peptide selection. Using the custom focused microarray of 500 selected peptides, we assayed the relative binding rates of tripeptides to Col IV, collagen type I (Col I, and albumin. We discovered a cluster of Col IV-selective adhesion peptides that exhibit bio-safety with endothelial cells. The results from this study can be used to improve the screening of regeneration-enhancing peptides.

[Distiller Yeasts Producing Antibacterial Peptides].

Science.gov (United States)

Klyachko, E V; Morozkina, E V; Zaitchik, B Ts; Benevolensky, S V

2015-01-01

A new method of controlling lactic acid bacteria contamination was developed with the use of recombinant Saccharomyces cerevisiae strains producing antibacterial peptides. Genes encoding the antibacterial peptides pediocin and plantaricin with codons preferable for S. cerevisiae were synthesized, and a system was constructed for their secretory expression. Recombinant S. cerevisiae strains producing antibacterial peptides effectively inhibit the growth of Lactobacillus sakei, Pediacoccus pentasaceus, Pediacoccus acidilactici, etc. The application of distiller yeasts producing antibacterial peptides enhances the ethanol yield in cases of bacterial contamination. Recombinant yeasts producing the antibacterial peptides pediocin and plantaricin can successfully substitute the available industrial yeast strains upon ethanol production.

Bioavailability and transport of peptides and peptide drugs into the brain.

Science.gov (United States)

Egleton, R D; Davis, T P

1997-01-01

Rational drug design and the targeting of specific organs has become a reality in modern drug development, with the emergence of molecular biology and receptor chemistry as powerful tools for the pharmacologist. A greater understanding of peptide function as one of the major extracellular message systems has made neuropeptides an important target in neuropharmaceutical drug design. The major obstacle to targeting the brain with therapeutics is the presence of the blood-brain barrier (BBB), which controls the concentration and entry of solutes into the central nervous system. Peptides are generally polar in nature, do not easily cross the blood-brain barrier by diffusion, and except for a small number do not have specific transport systems. Peptides can also undergo metabolic deactivation by peptidases of the blood, brain and the endothelial cells that comprise the BBB. In this review, we discuss a number of the recent strategies which have been used to promote peptide stability and peptide entry into the brain. In addition, we approach the subject of targeting specific transport systems that can be found on the brain endothelial cells, and describe the limitations of the methodologies that are currently used to study brain entry of neuropharmaceuticals.

Sistema de Classificação de Pacientes Pediátricos: construção e validação de categorias de cuidados

Directory of Open Access Journals (Sweden)

Ariane Polidoro Dini

2011-06-01

Full Text Available A classificação de pacientes é essencial para o gerenciamento de uma unidade. Entretanto, a literatura não dispõe de conceituações de categorias de pacientes pediátricos. Os objetivos deste estudo foram definir e validar categorias de cuidado de pacientes pediátricos, de acordo com o grau de dependência da equipe de enfermagem. Utilizou-se revisão bibliográfica para definição das categorias de cuidado e a validação de conteúdo das categorias propostas foi realizada por um grupo de juízes envolvidos em assistência e gerência de unidades pediátricas e por juízes envolvidos em ensino e pesquisa de pediatria e construção de instrumentos de classificação de pacientes. Foram estabelecidas e validadas cinco categorias de cuidados: Mínimos, Intermediários, Alta dependência, Semi-intensivo e Intensivo. A validação das categorias de cuidado subsidiou a construção de um sistema de classificação de pacientes pediátricos que poderá contribuir para o processo de tomada de decisão do enfermeiro na prática gerencial e assistencial.

Peptide array-based screening of human mesenchymal stem cell-adhesive peptides derived from fibronectin type III domain

International Nuclear Information System (INIS)

Okochi, Mina; Nomura, Shigeyuki; Kaga, Chiaki; Honda, Hiroyuki

2008-01-01

Human mesenchymal stem cell-adhesive peptides were screened based on the amino acid sequence of fibronectin type III domain 8-11 (FN-III 8-11 ) using a peptide array synthesized by the Fmoc-chemistry. Using hexameric peptide library of FN-III 8-11 scan, we identified the ALNGR (Ala-Leu-Asn-Gly-Arg) peptide that induced cell adhesion as well as RGDS (Arg-Gly-Asp-Ser) peptide. After incubation for 2 h, approximately 68% of inoculated cells adhere to the ALNGR peptide disk. Adhesion inhibition assay with integrin antibodies showed that the ALNGR peptide interacts with integrin β1 but not with αvβ3, indicating that the receptors for ALNGR are different from RGDS. Additionally, the ALNGR peptide expressed cell specificities for adhesion: cell adhesion was promoted for fibroblasts but not for keratinocytes or endotherial cells. The ALNGR peptide induced cell adhesion and promoted cell proliferation without changing its property. It is therefore useful for the construction of functional biomaterials

The Equine PeptideAtlas

DEFF Research Database (Denmark)

Bundgaard, Louise; Jacobsen, Stine; Sørensen, Mette Aamand

2014-01-01

Progress in MS-based methods for veterinary research and diagnostics is lagging behind compared to the human research, and proteome data of domestic animals is still not well represented in open source data repositories. This is particularly true for the equine species. Here we present a first...... Equine PeptideAtlas encompassing high-resolution tandem MS analyses of 51 samples representing a selection of equine tissues and body fluids from healthy and diseased animals. The raw data were processed through the Trans-Proteomic Pipeline to yield high quality identification of proteins and peptides....... The current release comprises 24 131 distinct peptides representing 2636 canonical proteins observed at false discovery rates of 0.2% at the peptide level and 1.4% at the protein level. Data from the Equine PeptideAtlas are available for experimental planning, validation of new datasets, and as a proteomic...

The CEASEMT system (Computer analysis of the thermomechanical structure behavior). The TRICO code, for analysis of three-dimensional structures comprising shells and beams - Statics - Dynamics - Elasticity - Plasticity - Buckling - Large displacements

International Nuclear Information System (INIS)

1977-01-01

The TRICO part of the CEA-SEMT system is concerned with the elasticity or plasticity computation of structures made of thin shells and beams. TRICO uses the finite element method for shells and beams. TRICO also allows the dynamic computing of structures: search for eigenmodes and eigenfrequencies or response to any sinusoidal excitation, response to time dependent loads (direct integration) in elasticity or plasticity. The mechanical structures can offer any shape and be composed of a number of materials. A special effort has been put on data input (read without any format), the data being arranged in optional commands with a precise physical sense corresponding to an order for the program. A dynamic control of the memory allows the size of the program to be adapted to that the problem to be processed. Results are printed on listing, or many be described on a magnetic tape [fr

Small leucine-rich repeat proteoglycans associated with mature insoluble elastin serve as binding sites for galectins.

Science.gov (United States)

Itoh, Aiko; Nonaka, Yasuhiro; Ogawa, Takashi; Nakamura, Takanori; Nishi, Nozomu

2017-11-01

We previously reported that galectin-9 (Gal-9), an immunomodulatory animal lectin, could bind to insoluble collagen preparations and exerted direct cytocidal effects on immune cells. In the present study, we found that mature insoluble elastin is capable of binding Gal-9 and other members of the human galectin family. Lectin blot analysis of a series of commercial water-soluble elastin preparations, PES-(A) ~ PES-(E), revealed that only PES-(E) contained substances recognized by Gal-9. Gal-9-interacting substances in PES-(E) were affinity-purified, digested with trypsin and then analyzed by reversed-phase HPLC. Peptide fragments derived from five members of the small leucine-rich repeat proteoglycan family, versican, lumican, osteoglycin/mimecan, prolargin, and fibromodulin, were identified by N-terminal amino acid sequence analysis. The results indicate that Gal-9 and possibly other galectins recognize glycans attached to small leucine-rich repeat proteoglycans associated with insoluble elastin and also indicate the possibility that mature insoluble elastin serves as an extracellular reservoir for galectins.

Peptide Nucleic Acids

DEFF Research Database (Denmark)

2004-01-01

A novel class of compounds known as peptide nucleic acids, bind complementary DNA and RNA strands, and generally do so more strongly than the corresponding DNA or RNA strands while exhibiting increased sequence specificity and solubility. The peptide nucleic acids comprise ligands selected from...

Repeating and non-repeating fast radio bursts from binary neutron star mergers

Science.gov (United States)

Yamasaki, Shotaro; Totani, Tomonori; Kiuchi, Kenta

2018-04-01

Most fast radio bursts (FRB) do not show evidence of repetition, and such non-repeating FRBs may be produced at the time of a merger of binary neutron stars (BNS), provided that the BNS merger rate is close to the high end of the currently possible range. However, the merger environment is polluted by dynamical ejecta, which may prohibit the radio signal from propagating. We examine this by using a general-relativistic simulation of a BNS merger, and show that the ejecta appears about 1 ms after the rotation speed of the merged star becomes the maximum. Therefore there is a time window in which an FRB signal can reach outside, and the short duration of non-repeating FRBs can be explained by screening after ejecta formation. A fraction of BNS mergers may leave a rapidly rotating and stable neutron star, and such objects may be the origin of repeating FRBs like FRB 121102. We show that a merger remnant would appear as a repeating FRB on a time scale of ˜1-10 yr, and expected properties are consistent with the observations of FRB 121102. We construct an FRB rate evolution model that includes these two populations of repeating and non-repeating FRBs from BNS mergers, and show that the detection rate of repeating FRBs relative to non-repeating ones rapidly increases with improving search sensitivity. This may explain why only the repeating FRB 121102 was discovered by the most sensitive FRB search with Arecibo. Several predictions are made, including the appearance of a repeating FRB 1-10 yr after a BNS merger that is localized by gravitational waves and subsequent electromagnetic radiation.

Peptide Integrated Optics.

Science.gov (United States)

Handelman, Amir; Lapshina, Nadezda; Apter, Boris; Rosenman, Gil

2018-02-01

Bio-nanophotonics is a wide field in which advanced optical materials, biomedicine, fundamental optics, and nanotechnology are combined and result in the development of biomedical optical chips. Silk fibers or synthetic bioabsorbable polymers are the main light-guiding components. In this work, an advanced concept of integrated bio-optics is proposed, which is based on bioinspired peptide optical materials exhibiting wide optical transparency, nonlinear and electrooptical properties, and effective passive and active waveguiding. Developed new technology combining bottom-up controlled deposition of peptide planar wafers of a large area and top-down focus ion beam lithography provides direct fabrication of peptide optical integrated circuits. Finding a deep modification of peptide optical properties by reconformation of biological secondary structure from native phase to β-sheet architecture is followed by the appearance of visible fluorescence and unexpected transition from a native passive optical waveguiding to an active one. Original biocompatibility, switchable regimes of waveguiding, and multifunctional nonlinear optical properties make these new peptide planar optical materials attractive for application in emerging technology of lab-on-biochips, combining biomedical photonic and electronic circuits toward medical diagnosis, light-activated therapy, and health monitoring. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New dendrimer - peptide host - guest complexes : towards dendrimers as peptide carriers

NARCIS (Netherlands)

Boas, U.; Sontjens, S.H.M.; Jensen, K.J.; Christensen, J.B.; Meijer, E.W.

2002-01-01

Adamantyl urea and adamantyl thiourea modified poly(propylene imine) dendrimers act as hosts for N-terminal tert-butoxycarbonyl (Boc)-protected peptides and form chloroform-soluble complexes. investigations with NMR spectroscopy show that the peptide is bound to the dendrimer by ionic interactions

Participación del óxido nítrico durante el desarrollo del absceso hepático amebiano Nitric oxide participation during amoebic liver abscess development

Directory of Open Access Journals (Sweden)

Joel Ramírez-Emiliano

2007-04-01

Full Text Available El óxido nítrico participa en funciones fisiológicas y fisiopatológicas, así como en el mecanismo de defensa del sistema inmunológico de mamíferos contra parásitos, virus y bacterias. La Entamoeba histolytica es un parásito protozoario causante de la amebiasis, la cual se caracteriza por el daño intestinal y la formación del absceso hepático amebiano (AHA. El desarrollo del absceso hepático amebiano en el hámster es similar al que desarrolla el humano, mientras que el ratón es resistente a la formación de este absceso, debido a un incremento en la producción de óxido nítrico. A diferencia del ratón, el desarrollo del absceso hepático amebiano en el hámster es debido a un exceso en la producción de óxido nítrico o posiblemente a una mayor susceptibilidad del hámster al daño producido por el óxido nítrico. Por lo tanto, sería importante realizar más estudios para determinar si en el humano, un exceso en la producción de óxido nítrico favorece la formación del absceso hepático amebiano.Nitric oxide participates in both physiological and pathophysiological functions, and it plays an important role in the mammalian immune system in killing or inhibiting the growth of many pathogens, including parasites, viruses and bacteria. Entamoeba histolytica is a protozoan parasite that causes amoebiasis, which is characterized by intestinal damage and amoebic liver abscess development. The development of amoebic liver abscess in hamsters is similar to that in humans, whereas mice are resistant to amoebic liver abscess development due to an increase in nitric oxide production. Unlike in mice, amoebic liver abscess development in hamsters is due to an excess in nitric oxide production or possibly to a greater susceptibility of the hamster to damage caused by nitric oxide. Therefore, it could be important to elucidate if, in humans, an excess in nitric oxide production favors amoebic liver abscess development.

Effective modification of cell death-inducing intracellular peptides by means of a photo-cleavable peptide array-based screening system.

Science.gov (United States)

Kozaki, Ikko; Shimizu, Kazunori; Honda, Hiroyuki

2017-08-01

Intracellular functional peptides that play a significant role inside cells have been receiving a lot of attention as regulators of cellular activity. Previously, we proposed a novel screening system for intracellular functional peptides; it combined a photo-cleavable peptide array system with cell-penetrating peptides (CPPs). Various peptides can be delivered into cells and intracellular functions of the peptides can be assayed by means of our system. The aim of the present study was to demonstrate that the proposed screening system can be used for assessing the intracellular activity of peptides. The cell death-inducing peptide (LNLISKLF) identified in a mitochondria-targeting domain (MTD) of the Noxa protein served as an original peptide sequence for screening of peptides with higher activity via modification of the peptide sequence. We obtained 4 peptides with higher activity, in which we substituted serine (S) at the fifth position with phenylalanine (F), valine (V), tryptophan (W), or tyrosine (Y). During analysis of the mechanism of action, the modified peptides induced an increase in intracellular calcium concentration, which was caused by the treatment with the original peptide. Higher capacity for cell death induction by the modified peptides may be caused by increased hydrophobicity or an increased number of aromatic residues. Thus, the present work suggests that the intracellular activity of peptides can be assessed using the proposed screening system. It could be used for identifying intracellular functional peptides with higher activity through comprehensive screening. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

PeptideNavigator: An interactive tool for exploring large and complex data sets generated during peptide-based drug design projects.

Science.gov (United States)

Diller, Kyle I; Bayden, Alexander S; Audie, Joseph; Diller, David J

2018-01-01

There is growing interest in peptide-based drug design and discovery. Due to their relatively large size, polymeric nature, and chemical complexity, the design of peptide-based drugs presents an interesting "big data" challenge. Here, we describe an interactive computational environment, PeptideNavigator, for naturally exploring the tremendous amount of information generated during a peptide drug design project. The purpose of PeptideNavigator is the presentation of large and complex experimental and computational data sets, particularly 3D data, so as to enable multidisciplinary scientists to make optimal decisions during a peptide drug discovery project. PeptideNavigator provides users with numerous viewing options, such as scatter plots, sequence views, and sequence frequency diagrams. These views allow for the collective visualization and exploration of many peptides and their properties, ultimately enabling the user to focus on a small number of peptides of interest. To drill down into the details of individual peptides, PeptideNavigator provides users with a Ramachandran plot viewer and a fully featured 3D visualization tool. Each view is linked, allowing the user to seamlessly navigate from collective views of large peptide data sets to the details of individual peptides with promising property profiles. Two case studies, based on MHC-1A activating peptides and MDM2 scaffold design, are presented to demonstrate the utility of PeptideNavigator in the context of disparate peptide-design projects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Group B streptococcal serine-rich repeat proteins promote interaction with fibrinogen and vaginal colonization.

Science.gov (United States)

Wang, Nai-Yu; Patras, Kathryn A; Seo, Ho Seong; Cavaco, Courtney K; Rösler, Berenice; Neely, Melody N; Sullam, Paul M; Doran, Kelly S

2014-09-15

Group B streptococcus (GBS) can cause severe disease in susceptible hosts, including newborns, pregnant women, and the elderly. GBS serine-rich repeat (Srr) surface glycoproteins are important adhesins/invasins in multiple host tissues, including the vagina. However, exact molecular mechanisms contributing to their importance in colonization are unknown. We have recently determined that Srr proteins contain a fibrinogen-binding region (BR) and hypothesize that Srr-mediated fibrinogen binding may contribute to GBS cervicovaginal colonization. In this study, we observed that fibrinogen enhanced wild-type GBS attachment to cervical and vaginal epithelium, and that this was dependent on Srr1. Moreover, purified Srr1-BR peptide bound directly to host cells, and peptide administration in vivo reduced GBS recovery from the vaginal tract. Furthermore, a GBS mutant strain lacking only the Srr1 "latching" domain exhibited decreased adherence in vitro and decreased persistence in a mouse model of GBS vaginal colonization, suggesting the importance of Srr-fibrinogen interactions in the female reproductive tract. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Uma versão compacta do motor elétrico de Faraday para demonstração em sala de aula

Directory of Open Access Journals (Sweden)

Osmar Henrique Moura Silva

2013-06-01

Full Text Available http://dx.doi.org/10.5007/2175-7941.2013v30n2p385 O “motor” elétrico de Michael Faraday (1791-1867 é versado como o precursor dos motores elétricos atuais e um equipamento interessante no estudo introdutório do assunto. Um trabalho anterior divulgou uma montagem deste motor mais bem adaptada aos ambientes educativos não formais, abrangendo suas duas variantes: uma, com haste móvel e ímã fixo; outra, com haste fixa e ímã móvel. Apresenta-se aqui uma elaboração desse motor na primeira destas variantes que se diferencia nas dimensões e peso, sendo de fácil transporte e uso em sala de aula por apropriação da energia elétrica padrão de 127V.

Dendroaspis natriuretic peptide binds to the natriuretic peptide clearance receptor

International Nuclear Information System (INIS)

Johns, Douglas G.; Ao, Zhaohui; Heidrich, Bradley J.; Hunsberger, Gerald E.; Graham, Taylor; Payne, Lisa; Elshourbagy, Nabil; Lu, Quinn; Aiyar, Nambi; Douglas, Stephen A.

2007-01-01

Dendroaspis natriuretic peptide (DNP) is a newly-described natriuretic peptide which lowers blood pressure via vasodilation. The natriuretic peptide clearance receptor (NPR-C) removes natriuretic peptides from the circulation, but whether DNP interacts with human NPR-C directly is unknown. The purpose of this study was to test the hypothesis that DNP binds to NPR-C. ANP, BNP, CNP, and the NPR-C ligands AP-811 and cANP(4-23) displaced [ 125 I]-ANP from NPR-C with pM-to-nM K i values. DNP displaced [ 125 I]-ANP from NPR-C with nM potency, which represents the first direct demonstration of binding of DNP to human NPR-C. DNP showed high pM affinity for the GC-A receptor and no affinity for GC-B (K i > 1000 nM). DNP was nearly 10-fold more potent than ANP at stimulating cGMP production in GC-A expressing cells. Blockade of NPR-C might represent a novel therapeutic approach in augmenting the known beneficial actions of DNP in cardiovascular diseases such as hypertension and heart failure

Identidade cifrada no corpo: o bertillonnage e o gabinete antropométrico na polícia do Rio de Janeiro, 1894-1903

Directory of Open Access Journals (Sweden)

Diego Galeano

Full Text Available Nos primeiros anos republicanos do Brasil, vários juristas, criminologistas e policiais difundiram uma novidade recém-chegada da França: o sistema antropométrico para a identificação de pessoas, adotado na polícia parisiense por iniciativa de Alphonse Bertillon (1853-1914. A ideia de introduzir o método chamado bertillonnage no Brasil apareceu, desde 1889, em relatórios governamentais, livros de viagem e jornais. Um gabinete antropométrico foi instalado na polícia do Rio de Janeiro em 1894, mas quase não funcionou até 1899, quando foi reorganizado e, em 1900, a identificação de criminosos pelo método foi estabelecida por decreto. Instrumentos de medição e livros foram trazidos de Paris, a 'metrópole' da identificação policial, mas a história do gabinete antropométrico da então capital brasileira não deve ser interpretada simplesmente como um processo de aplicação imitativa de um método estrangeiro. É o que demonstra este artigo, que procura analisar a constituição transnacional do bertillonnage e os complexos processos de leitura, tradução e adaptação envolvidos no uso da antropometria no âmbito das práticas policiais no Rio de Janeiro.

Återvinning av dryckeskartonger : En studie som syftar till att öka återvinningsgraden av Tetra Paks förpackningar i Indonesien

OpenAIRE

Backlund, Per

2014-01-01

People of the modern world consume more than they ever used to do. Because of the close correlation between consumption and the amount of waste, the waste volume is also expected to increase. The purpose of this study is to examine if some measures in the recycling process from Sweden could be implemented in Indonesia. In fact, Indonesia is one of the countries in which the waste management system is struggling. Tetra Pak, one of the world leading producer of food packaging, is studied in thi...

Matrix-assisted peptide synthesis on nanoparticles.

Science.gov (United States)

Khandadash, Raz; Machtey, Victoria; Weiss, Aryeh; Byk, Gerardo

2014-09-01

We report a new method for multistep peptide synthesis on polymeric nanoparticles of differing sizes. Polymeric nanoparticles were functionalized via their temporary embedment into a magnetic inorganic matrix that allows multistep peptide synthesis. The matrix is removed at the end of the process for obtaining nanoparticles functionalized with peptides. The matrix-assisted synthesis on nanoparticles was proved by generating various biologically relevant peptides. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

Bromine isotopic signature facilitates de novo sequencing of peptides in free-radical-initiated peptide sequencing (FRIPS) mass spectrometry.

Science.gov (United States)

Nam, Jungjoo; Kwon, Hyuksu; Jang, Inae; Jeon, Aeran; Moon, Jingyu; Lee, Sun Young; Kang, Dukjin; Han, Sang Yun; Moon, Bongjin; Oh, Han Bin

2015-02-01

We recently showed that free-radical-initiated peptide sequencing mass spectrometry (FRIPS MS) assisted by the remarkable thermochemical stability of (2,2,6,6-tetramethyl-piperidin-1-yl)oxyl (TEMPO) is another attractive radical-driven peptide fragmentation MS tool. Facile homolytic cleavage of the bond between the benzylic carbon and the oxygen of the TEMPO moiety in o-TEMPO-Bz-C(O)-peptide and the high reactivity of the benzylic radical species generated in •Bz-C(O)-peptide are key elements leading to extensive radical-driven peptide backbone fragmentation. In the present study, we demonstrate that the incorporation of bromine into the benzene ring, i.e. o-TEMPO-Bz(Br)-C(O)-peptide, allows unambiguous distinction of the N-terminal peptide fragments from the C-terminal fragments through the unique bromine doublet isotopic signature. Furthermore, bromine substitution does not alter the overall radical-driven peptide backbone dissociation pathways of o-TEMPO-Bz-C(O)-peptide. From a practical perspective, the presence of the bromine isotopic signature in the N-terminal peptide fragments in TEMPO-assisted FRIPS MS represents a useful and cost-effective opportunity for de novo peptide sequencing. Copyright © 2015 John Wiley & Sons, Ltd.

Intravenous glucagon-like peptide 1 normalizes blood glucose after major surgery in patients with type 2 diabetes

DEFF Research Database (Denmark)

Meier, Juris J; Weyhe, Dirk; Michaely, Mark

2004-01-01

of GLP-1 (1.2 pmol x kg x min) and placebo over 8 hrs, each administered in randomized order in the fasting state. C-reactive protein concentrations of 4.9+/-4.2 mg/dL indicated a systemic inflammation. Blood was drawn in 30-min intervals for glucose (glucose oxidase), insulin, C-peptide, glucagon...... practicability and the risk of hypoglycemia. Therefore, the glucose-lowering effect of the incretin hormone glucagon-like peptide 1 (GLP-1) was investigated in patients with type 2 diabetes after major surgery. DESIGN: Randomised clinical study. SETTING: A surgical unit of a university hospital. PATIENTS......, and GLP-1 (specific immunoassays). Statistics were done with repeated-measures analysis of variance and Duncan's post hoc tests. MAIN RESULTS: During the intravenous infusion of GLP-1, plasma glucose concentrations were significantly lowered, reaching the normoglycemic fasting glucose range within 150...

Crystal structure of diaphorin methanol monosolvate isolated from Diaphorina citri Kuwayama, the insect vector of citrus greening disease.

Science.gov (United States)

Szebenyi, D Marian; Kriksunov, Irina; Howe, Kevin J; Ramsey, John S; Hall, David G; Heck, Michelle L; Krasnoff, Stuart B

2018-04-01

The title compound C 22 H 39 NO 9 ·CH 3 OH [systematic name: ( S )- N -(( S )-{(2 S ,4 R ,6 R )-6-[( S )-2,3-di-hydroxy-prop-yl]-4-hy-droxy-5,5-di-methyl-tetra-hydro-2 H -pyran-2-yl}(hy-droxy)meth-yl)-2-hy-droxy-2-[(2 R ,5 R ,6 R )-2-meth-oxy-5,6-dimeth-yl-4-methyl-ene-tetra-hydro-2 H -pyran-2-yl]acetamide methanol monosolvate], was isolated from the Asian citrus psyllid, Diaphorina citri Kuwayama, and crystallizes in the space group P 2 1 . ' Candidatus Profftella armatura' a bacterial endosymbiont of D. citri , biosynthesizes diaphorin, which is a hybrid polyketide-nonribosomal peptide comprising two highly substituted tetra-hydro-pyran rings joined by an N -acyl aminal bridge [Nakabachi et al. (2013 ▸). Curr. Biol. 23 , 1478-1484]. The crystal structure of the title compound establishes the complete relative configuration of diaphorin, which agrees at all nine chiral centers with the structure of the methanol monosolvate of the di- p -bromo-benzoate derivative of pederin, a biogenically related compound whose crystal structure was reported previously [Furusaki et al. (1968 ▸). Tetra-hedron Lett. 9 , 6301-6304]. Thus, the absolute configuration of diaphorin is proposed by analogy to that of pederin.

Estudos métricos da informação: primeiras aproximações 10.5007/1518-2924.2008v13nesp1p116

Directory of Open Access Journals (Sweden)

Daisy Pires Noronha

2008-04-01

Full Text Available Apresentam-se alguns conceitos e considerações fundamentais dos estudos métricos da informação e os principais métodos e técnicas utilizadas, como a bibliometria, cienciometria, informetria, webmetria, patentometria e biblioteconometria. Discute-se o ciclo de comunicação científica, destacando-se os principais indicadores de input (insumo e output (produto, assim como, a importância da publicação dos resultados da pesquisa científica e do processo de avaliação pelos pares. Comentam-se algumas características e aplicações das leis bibliométricas e de outros recursos utilizados nos estudos métricos da informação.

Evaluation of the amyloid beta-GFP fusion protein as a model of amyloid beta peptides-mediated aggregation: A study of DNAJB6 chaperone

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Rasha Mohamed Hussein

2015-07-01

Full Text Available Alzheimer’s disease is a progressive neurodegenerative disease characterized by the accumulation and aggregation of extracellular amyloid β (Aβ peptides and intracellular aggregation of hyper-phosphorylated tau protein. Recent evidence indicates that accumulation and aggregation of intracellular amyloid β peptides may also play a role in disease pathogenesis. This would suggest that intracellular Heat Shock Proteins (HSP that maintain cellular protein homeostasis might be candidates for disease amelioration. We recently found that DNAJB6, a member of DNAJ family of heat shock proteins, effectively prevented the aggregation of short aggregation-prone peptides containing large poly glutamines (associated with CAG repeat diseases both in vitro and in cells. Moreover, recent in vitro data showed that DNAJB6 can delay the aggregation of Aβ42 peptides. In this study, we investigated the ability of DNAJB6 to prevent the aggregation of extracellular and intracellular Aβ peptides using transfection of HEK293 cells with Aβ-GFP fusion construct and performing western blotting and immunofluorescence techniques. We found that DNAJB6 indeed suppresses Aβ-GFP aggregation, but not seeded aggregation initiated by extracellular Aβ peptides. Unexpectedly and unlike what we found for peptide-mediated aggregation, DNAJB6 required interaction with HSP70 to prevent the aggregation of the Aβ-GFP fusion protein and its J-domain was crucial for its anti-aggregation effect. In addition, other DNAJ proteins as well as HSPA1a overexpression also suppressed Aβ-GFP aggregation efficiently. Our findings suggest that Aβ aggregation differs from poly Q peptide induced aggregation in terms of chaperone handling and sheds doubt on the usage of Aβ-GFP fusion construct for studying Aβ peptide aggregation in cells.

Nuevos derivados asimétricos de la carbohidracida y tiocarbohidracida como reactivos analíticos

OpenAIRE

Morales Millán, María Teresa Auxiliadora

1987-01-01

1.- En la presente Memoria, se han estudiado las caracte rísticas físico-químicas y de las posibilidades analíticas de dos derivados asimétricos de la carbohidracida y tiocarbohidracida: la 1-(di-(2-piridil)metiliden)-5-(salicilmetiliden)-carbohidrazona (DPSC), y la 1-(di-(2-piridil)metiliden)-5-(salicilmetiliden)-tiocarbohidrazona (DPST). 2.- La síntesis de los reactivos se ha efectuado en dos pasos. En primer lugar se obtuvieron los correspondientes monoderivados siguiendo la técnica de...

Synthesis of peptide thioacids at neutral pH using bis(2-sulfanylethyl)amido peptide precursors.

Science.gov (United States)

Pira, Silvain L; Boll, Emmanuelle; Melnyk, Oleg

2013-10-18

Reaction of bis(2-sulfanylethyl)amido (SEA) peptides with triisopropylsilylthiol in water at neutral pH yields peptide thiocarboxylates. An alkylthioester derived from β-alanine was used to trap the released bis(2-sulfanylethyl)amine and displace the equilibrium toward the peptide thiocarboxylate.

Surface acoustic wave nebulization of peptides as a microfluidic interface for mass spectrometry.

Science.gov (United States)

Heron, Scott R; Wilson, Rab; Shaffer, Scott A; Goodlett, David R; Cooper, Jonathan M

2010-05-15

We describe the fabrication of a surface acoustic wave (SAW) device on a LiNbO(3) piezoelectric transducer for the transfer of nonvolatile analytes to the gas phase at atmospheric pressure (a process referred to as nebulization or atomization). We subsequently show how such a device can be used in the field of mass spectrometry (MS) detection, demonstrating that SAW nebulization (SAWN) can be performed either in a discontinuous or pulsed mode, similar to that for matrix assisted laser desorption ionization (MALDI) or in a continuous mode like electrospray ionization (ESI). We present data showing the transfer of peptides to the gas phase, where ions are detected by MS. These peptide ions were subsequently fragmented by collision-induced dissociation, from which the sequence was assigned. Unlike MALDI mass spectra, which are typically contaminated with matrix ions at low m/z, the SAWN generated spectra had no such interference. In continuous mode, the SAWN plume was sampled on a microsecond time scale by a linear ion trap mass spectrometer and produced multiply charged peptide precursor ions with a charge state distribution shifted to higher m/z compared to an identical sample analyzed by ESI. The SAWN technology also provides the opportunity to re-examine a sample from a flat surface, repeatedly. The process can be performed without the need for capillaries, which can clog, reservoirs, which dilute the sample, and electrodes, which when in direct contact with sample, cause unwanted electrochemical oxidation. In both continuous and pulsed sampling modes, the quality of precursor ion scans and tandem mass spectra of peptides was consistent across the plume's lifetime.

Determination of the water content in tetra-ammonium uranyl tricarbonate by the Karl Fischer reagent method

International Nuclear Information System (INIS)

Sisti, C.; Grigoletto, T.

1990-08-01

Two methods are compared for the determination of water content in tetra-ammonium uranyl tricarbonate by the Karl Fischer reagent method. In the first method it is Known that the carbonate reacts stoichiometrically with the iodine content of the Karl Fischer reagent in the same way it reacts with the water (mole of apparent H 2 O per mole of carbonate is produced). In this case, the carbonate content in the sample is determined and a suitable correction is applied to take into account the apparent water results. In the second method it is performed an extraction of the moisture by adding methanol to the sample in an independent flask. After the decantation, an aliquot of the clear supernatant methanol is taken for the determination of water content by the Karl Fischer reagent method. (author) [pt

Photodissociative Cross-Linking of Non-covalent Peptide-Peptide Ion Complexes in the Gas Phase

Science.gov (United States)

Nguyen, Huong T. H.; Andrikopoulos, Prokopis C.; Rulíšek, Lubomír; Shaffer, Christopher J.; Tureček, František

2018-05-01

We report a gas-phase UV photodissociation study investigating non-covalent interactions between neutral hydrophobic pentapeptides and peptide ions incorporating a diazirine-tagged photoleucine residue. Phenylalanine (Phe) and proline (Pro) were chosen as the conformation-affecting residues that were incorporated into a small library of neutral pentapeptides. Gas-phase ion-molecule complexes of these peptides with photo-labeled pentapeptides were subjected to photodissociation. Selective photocleavage of the diazirine ring at 355 nm formed short-lived carbene intermediates that underwent cross-linking by insertion into H-X bonds of the target peptide. The cross-link positions were established from collision-induced dissociation tandem mass spectra (CID-MS3) providing sequence information on the covalent adducts. Effects of the amino acid residue (Pro or Phe) and its position in the target peptide sequence were evaluated. For proline-containing peptides, interactions resulting in covalent cross-links in these complexes became more prominent as proline was moved towards the C-terminus of the target peptide sequence. The photocross-linking yields of phenylalanine-containing peptides depended on the position of both phenylalanine and photoleucine. Density functional theory calculations were used to assign structures of low-energy conformers of the (GLPMG + GLL*LK + H)+ complex. Born-Oppenheimer molecular dynamics trajectory calculations were used to capture the thermal motion in the complexes within 100 ps and determine close contacts between the incipient carbene and the H-X bonds in the target peptide. This provided atomic-level resolution of potential cross-links that aided spectra interpretation and was in agreement with experimental data. [Figure not available: see fulltext.

Proceso del control integrado de moscas de la fruta (Díptera: Tephritidae) en los cítricos de exportación a los Estados Unidos, Huaral – Lima, 2014

OpenAIRE

Cornejo Campos, José Carlos

2016-01-01

La presente investigación titulada: “Proceso del control integrado de moscas de la fruta (Díptera: Tephritidae) en los cítricos de exportación a los Estados Unidos, Huaral – Lima, 2014.”, tuvo como objetivo general: Describir el nivel del proceso del control integrado de moscas de la fruta en los cítricos de exportación a los Estados Unidos, Huaral – Lima, 2014. Esto como respuesta al problema: ¿Cuál es el nivel del proceso del control integrado de moscas de la fruta en los ...

Maize Bioactive Peptides against Cancer

Science.gov (United States)

Díaz-Gómez, Jorge L.; Castorena-Torres, Fabiola; Preciado-Ortiz, Ricardo E.; García-Lara, Silverio

2017-06-01

Cancer is one of the main chronic degenerative diseases worldwide. In recent years, consumption of whole-grain cereals and their derived food products has been associated with reduction risks of various types of cancer. Cereals main biomolecules includes proteins, peptides, and amino acids present in different quantities within the grain. The nutraceutical properties associated with peptides exerts biological functions that promote health and prevent this disease. In this review, we report the current status and advances on maize peptides regarding bioactive properties that have been reported such as antioxidant, antihypertensive, hepatoprotective, and anti-tumour activities. We also highlighted its biological potential through which maize bioactive peptides exert anti-cancer activity. Finally, we analyse and emphasize the possible areas of application for maize peptides.

Insect Peptides - Perspectives in Human Diseases Treatment.

Science.gov (United States)

Chowanski, Szymon; Adamski, Zbigniew; Lubawy, Jan; Marciniak, Pawel; Pacholska-Bogalska, Joanna; Slocinska, Malgorzata; Spochacz, Marta; Szymczak, Monika; Urbanski, Arkadiusz; Walkowiak-Nowicka, Karolina; Rosinski, Grzegorz

2017-01-01

Insects are the largest and the most widely distributed group of animals in the world. Their diversity is a source of incredible variety of different mechanisms of life processes regulation. There are many agents that regulate immunology, reproduction, growth and development or metabolism. Hence, it seems that insects may be a source of numerous substances useful in human diseases treatment. Especially important in the regulation of insect physiology are peptides, like neuropeptides, peptide hormones or antimicrobial peptides. There are two main aspects where they can be helpful, 1) Peptides isolated from insects may become potential drugs in therapy of different diseases, 2) A lot of insect peptide hormones show structural or functional homology to mammalian peptide hormones and the comparative studies may give a new look on human disorders. In our review we focused on three group of insect derived peptides: 1) immune-active peptides, 2) peptide hormones and 3) peptides present in venoms. In our review we try to show the considerable potential of insect peptides in searching for new solutions for mammalian diseases treatment. We summarise the knowledge about properties of insect peptides against different virulent agents, anti-inflammatory or anti-nociceptive properties as well as compare insect and mammalian/vertebrate peptide endocrine system to indicate usefulness of knowledge about insect peptide hormones in drug design. The field of possible using of insect delivered peptide to therapy of various human diseases is still not sufficiently explored. Undoubtedly, more attention should be paid to insects due to searching new drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Fibroma desmoplásico de maxilar en paciente pediátrico: Reporte de caso

OpenAIRE

Roberto Gerber Mora; Sergio Castro Mora; Joseph Ulate Jiménez

2015-01-01

La presencia de tumefacciones en la cavidad bucal del paciente pediátrico puede ser indicativo de gran cantidad de patologías y enfermedades sistémicas, algunas incluso pueden perjudicar el bienestar del mismo. El Fibroma desmoplásico es un tumor óseo benigno, localmente destructivo, catalogado como muy poco frecuente. Se reporta el caso de un niño de 4 años con fibroma desmoplásico en el maxilar de alrededor de 2 años de evolución, observándose como una tumefacción generalizada del segundo c...

Trastornos psiquiátricos frecuentes post infarto agudo al miocardio y su relación pronóstica. Revisión de la literatura.

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Manuel Mallol Simmonds

2017-07-01

Full Text Available La enfermedad cardiovascular es la principal causa de muerte a nivel mundial. De ella, el Infarto Agudo al Miocardio (IAM y el Accidente Cerebrovascular (AVC se encuentran fuertemente asociados a los cambios ambientales y sociales del último tiempo, tales como aumento de ingesta de comida rápida, sedentarismo, tabaquismo, entre otros. Algunos trastornos psiquiátricos que aparecen a corto y largo plazo posterior al evento coronario agudo tienen una implicancia directa en la morbimortalidad cardiovascular y global. De ellos, la depresión representa el trastorno psiquiátrico más frecuente, pudiendo encontrarse en 3 de cada 10 pacientes que tuvieron un IAM. La depresión aumenta las hospitalizaciones, disminuye la adherencia terapéutica y empeora el pronóstico cardiovascular a largo plazo.  La fisiopatología en lo anterior es explicada en parte por alteraciones en el eje neuroendocrino y la respuesta al estrés, mientras que otros fenómenos permanecen aún desconocidos. Dentro de otros trastornos psiquiátricos asociados a un IAM se encuentran el delirium, ansiedad y trastornos de la personalidad. En función de lo anterior, se hace necesaria la incorporación de un sistema continuo de monitoreo y apoyo en salud mental en este grupo de pacientes para mejorar tanto su pronóstico como la calidad de vida.

Peptide imprinted receptors for the determination of the small cell lung cancer associated biomarker progastrin releasing peptide

DEFF Research Database (Denmark)

Qader, A. A.; Urraca, J.; Torsetnes, S. B.

2014-01-01

Peptide imprinted polymers were developed for detection of progastrin releasing peptide (ProGRP); a low abundant blood based biomarker for small cell lung cancer. The polymers targeted the proteotypic nona-peptide sequence NLLGLIEAK and were used for selective enrichment of the proteotypic peptide...... prior to LCMS based quantification. Peptide imprinted polymers with the best affinity characteristics were first identified from a 96-polymer combinatorial library. The effects of functional monomers, crosslinker, porogen, and template on adsorption capacity and selectivity for NLLGLIEAK were...

Study on the C-peptide radioimmunoassay with synthetized connecting peptide

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, S; Sasaki, T; Nakayama, H; Watanabe, T; Aoki, S [Hokkaido Univ., Sapporo (Japan). School of Medicine

1976-01-01

A method of C-peptide radioimmunoassay with the synthetized connecting peptide by Yanaihara was tested for the determination of serum C-peptide immunoreactivity (CPR) in normal people and in diabetics with or without insulin treatment. The CPR value obtained by this method was not interfered with by the presence of serum proteins or by the insulin of people with or without insulin treatment judged by the dilution test and the recovery test. The normal fasting CPR was 2.80 +- 0.78 ng/ml with the synthetized C-peptide as a standard. The CPR value increased and reached a maximum 90 minutes after the ingestion of 50 g of glucose. The increase after the glucose loading reduced corresponding to the severity of diabetes, and some juvenile-onset diabetes showed no response. Adult-type diabetics under insulin treatment, however, showed weak but significant CPR response. The increment of CPR and immunoreactive insulin after glucose loading in normal people and non-treated diabetics was well correlated (..gamma..=0.8262). Judged from the above mentioned results, CPR determination in insulin-treated diabetics was thought to be a useful method for the assessment of the insulin-secreting ability of beta-cells of the pancreas.

A Unified Model for Repeating and Non-repeating Fast Radio Bursts

International Nuclear Information System (INIS)

Bagchi, Manjari

2017-01-01

The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

A Unified Model for Repeating and Non-repeating Fast Radio Bursts

Energy Technology Data Exchange (ETDEWEB)

Bagchi, Manjari, E-mail: manjari@imsc.res.in [The Institute of Mathematical Sciences (IMSc-HBNI), 4th Cross Road, CIT Campus, Taramani, Chennai 600113 (India)

2017-04-01

The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

Repeatability of Cryogenic Multilayer Insulation

Science.gov (United States)

Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

2017-12-01

Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation (MLI) has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five Glenn Research Center (GRC) provided coupons with 25 layers was shown to be +/- 8.4% whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0%. A second group of 10 coupons has been fabricated by Yetispace and tested by Florida State University, the repeatability between coupons has been shown to be +/- 15-25%. Based on detailed statistical analysis, the data has been shown to be statistically significant.

Separation properties of aluminium-plastic laminates in post-consumer Tetra Pak with mixed organic solvent.

Science.gov (United States)

Zhang, S F; Zhang, L L; Luo, K; Sun, Z X; Mei, X X

2014-04-01

The separation properties of the aluminium-plastic laminates in postconsumer Tetra Pak structure were studied in this present work. The organic solvent blend of benzene-ethyl alcohol-water was used as the separation reagent. Then triangle coordinate figure analysis was taken to optimize the volume proportion of various components in the separating agent and separation process. And the separation temperature of aluminium-plastic laminates was determined by the separation time, efficiency, and total mass loss of products. The results show that cost-efficient separations perform best with low usage of solvents at certain temperatures, for certain times, and within a certain range of volume proportions of the three components in the solvent agent. It is also found that similar solubility parameters of solvents and polyethylene adhesives (range 26.06-34.85) are a key factor for the separation of the aluminium-plastic laminates. Such multisolvent processes based on the combined-system concept will be vital to applications in the recycling industry.

Tidbits for the synthesis of bis(2-sulfanylethyl)amido (SEA) polystyrene resin, SEA peptides and peptide thioesters.

Science.gov (United States)

Ollivier, Nathalie; Raibaut, Laurent; Blanpain, Annick; Desmet, Rémi; Dheur, Julien; Mhidia, Reda; Boll, Emmanuelle; Drobecq, Hervé; Pira, Silvain L; Melnyk, Oleg

2014-02-01

Protein total chemical synthesis enables the atom-by-atom control of the protein structure and therefore has a great potential for studying protein function. Native chemical ligation of C-terminal peptide thioesters with N-terminal cysteinyl peptides and related methodologies are central to the field of protein total synthesis. Consequently, methods enabling the facile synthesis of peptide thioesters using Fmoc-SPPS are of great value. Herein, we provide a detailed protocol for the preparation of bis(2-sulfanylethyl)amino polystyrene resin as a starting point for the synthesis of C-terminal bis(2-sulfanylethyl)amido peptides and of peptide thioesters derived from 3-mercaptopropionic acid. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.

Determinación del índice esclerométrico en hormigones: factores que lo afectan

Directory of Open Access Journals (Sweden)

José Gabriel Gómez Cortés

1987-09-01

Full Text Available Se analizan los principales factores que influyen en la determinación de la resistencia mecánica de un concreto evaiuada mediante índice esclerométrico: tipo de cemento, contenido, tamaño y tipo del agregado, forma y textura de la superficie, posición del aparato, cabo rotación superficial, capas diferentes, condiciones de humedad superficiales, destreza del operador, Se concluye que la dispersión de resultados es bastante amplia como para que sea de utilidad en casos prácticos

Fisioterapia en pacientes geriátricos; Fractura de cadera. Revisión bibliográfica

OpenAIRE

Pérez Bermúdez, Nerea

2015-01-01

La fractura de cadera en pacientes geriátricos constituye un problema muy importante en la sociedad española ya que tiene una alta incidencia, la cual no puede explicarse solo por el envejecimiento poblacional sino que residen en muchos más factores. Estas fracturas son una causa muy frecuente de ingreso hospitalario, con su posterior intervención quirúrgica y su tratamiento de fisioterapia. Además representa una de las causas más importantes de mortalidad entre esta población. También pro...

Asociación entre agenesia dental y maloclusión en pacientes pediátricos

OpenAIRE

A. Carolina Medina; Rodrigo Del Pozo

2013-01-01

Introducción: La agenesia dental es la anomalía del desarrollo más frecuente en el ser humano, asociándose a maloclusiones y alteraciones funcionales. Objetivo: El objetivo de la presente investigación es determinar la asociación entre la agenesia de dientes permanentes y la presencia de maloclusiones en pacientes pediátricos en el área Metropolitana de Caracas, Venezuela. Material y métodos: Fueron evaluados 1.188 radiografías panorámicas y 648 registros ortodóncicos de pacientes sanos con e...

Floral organ abscission peptide IDA and its HAE/HSL2 receptors control cell separation during lateral root emergence

OpenAIRE

Kumpf, Robert P.; Shi, Chun-Lin; Larrieu, Antoine; Stø, Ida Myhrer; Butenko, Melinka A.; Péret, Benjamin; Riiser, Even Sannes; Bennett, Malcolm J.; Aalen, Reidunn B.

2013-01-01

Throughout their life cycle, plants produce new organs, such as leaves, flowers, and lateral roots. Organs that have served their purpose may be shed after breakdown of primary cell walls between adjacent cell files at the site of detachment. In Arabidopsis, floral organs abscise after pollination, and this cell separation event is controlled by the peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE) and HAESA-LI...

Spectroscopic analysis of the interaction between tetra-(p-sulfoazophenyl-4-aminosulfonyl-substituted aluminum (III phthalocyanines and serum albumins

Directory of Open Access Journals (Sweden)

Liqin Zheng

2017-03-01

Full Text Available The binding interaction between tetra-(p-sulfoazophenyl-4-aminosulfonyl-substituted aluminum (III phthalocyanine (AlPc, and two-serum albumins (bovine serum albumin (BSA and human serum albumin (HSA has been investigated. AlPc could quench the intrinsic fluorescence of BSA and HSA through a static quenching process. The primary and secondary binding sites of AlPc on BSA were domain I and III of BSA. The primary binding site of AlPc on HSA was domain I, and the secondary binding sites of AlPc on HSA were found at domains I and II. Our results suggest that AlPc readily interact with BSA and HSA implying that the amphiphilic substituents AlPc may contribute to their transportation in the blood.

Streptococcus gallolyticus subsp. pasteurianus en líquido cefalorraquídeo de un paciente pediátrico

Directory of Open Access Journals (Sweden)

Liz M Vélez Balestro

Full Text Available Hasta la fecha se han descrito casos de meningitis por Streptococcus gallolyticus subsp. pasteurianus en adultos, y de los pocos casos pediátricos, el mayor número se presentó en neonatos. En este trabajo presentamos un caso de meningitis y bacteriemia por este estreptococo en un paciente de 9 meses, con reiteradas hospitalizaciones por enfermedades respiratorias; este constituye el primer aislamiento documentado del citado microorganismo en Santa Fe.

Radiopharmaceutical development of radiolabelled peptides

Energy Technology Data Exchange (ETDEWEB)

Fani, Melpomeni; Maecke, Helmut R. [University Hospital Freiburg, Department of Nuclear Medicine, Freiburg (Germany)

2012-02-15

Receptor targeting with radiolabelled peptides has become very important in nuclear medicine and oncology in the past few years. The overexpression of many peptide receptors in numerous cancers, compared to their relatively low density in physiological organs, represents the molecular basis for in vivo imaging and targeted radionuclide therapy with radiolabelled peptide-based probes. The prototypes are analogs of somatostatin which are routinely used in the clinic. More recent developments include somatostatin analogs with a broader receptor subtype profile or with antagonistic properties. Many other peptide families such as bombesin, cholecystokinin/gastrin, glucagon-like peptide-1 (GLP-1)/exendin, arginine-glycine-aspartic acid (RGD) etc. have been explored during the last few years and quite a number of potential radiolabelled probes have been derived from them. On the other hand, a variety of strategies and optimized protocols for efficient labelling of peptides with clinically relevant radionuclides such as {sup 99m}Tc, M{sup 3+} radiometals ({sup 111}In, {sup 86/90}Y, {sup 177}Lu, {sup 67/68}Ga), {sup 64/67}Cu, {sup 18}F or radioisotopes of iodine have been developed. The labelling approaches include direct labelling, the use of bifunctional chelators or prosthetic groups. The choice of the labelling approach is driven by the nature and the chemical properties of the radionuclide. Additionally, chemical strategies, including modification of the amino acid sequence and introduction of linkers/spacers with different characteristics, have been explored for the improvement of the overall performance of the radiopeptides, e.g. metabolic stability and pharmacokinetics. Herein, we discuss the development of peptides as radiopharmaceuticals starting from the choice of the labelling method and the conditions to the design and optimization of the peptide probe, as well as some recent developments, focusing on a selected list of peptide families, including somatostatin

Different target surfaces for the analysis of peptides, peptide mixtures and peptide mass fingerprints by AP-MALDI ion trap-mass spectrometry.

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Pittenauer, Ernst; Kassler, Alexander; Haubner, Roland; Allmaier, Günter

2011-06-10

The desorption/ionization behavior of individual peptides, an equimolare peptide mixture and a tryptic digest was investigated by AP-MALDI-IT-MS using four different target materials (gold-covered stainless steel (SS), titanium nitride-covered SS, hand-polished SS, and microdiamond-covered hardmetal) under identical conditions. Gold-covered as well as polished SS targets yielded comparable mass spectra for peptides and peptide mixture in the low pMol-range. The first target exhibited superior data down to the 10fMol-range. In contrast, titanium nitride-covered SS and microdiamond-covered hardmetal AP-MALDI-targets yielded poor sensitivity. These observations could be correlated with the surface roughness of the targets determined by 3D-confocal-white-light-microscopy. The roughest surfaces were found for titanium nitride-covered SS and microdiamond-covered hardmetal material showing both poor MS sensitivity. A less rough surface could be determined for the hand-polished SS target and the smoothest surface was found for the gold-covered target yielding the best sensitivity of all surfaces. These differences in the roughness having a strong impact on the ultimate sensitivity obtainable for peptide samples could be corroborated by electron microscopy. A peptide mixture covering a wide range of molecular weights and a tryptic protein digest (from 2-DE) exhibit the same behavior. This clearly indicates that the smooth gold-covered SS target is the surface of choice in AP-MALDI MS proteomics. Copyright © 2010. Published by Elsevier B.V.

Deployment Repeatability

Science.gov (United States)

2016-04-01

evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

Material Binding Peptides for Nanotechnology

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Urartu Ozgur Safak Seker

2011-02-01

Full Text Available Remarkable progress has been made to date in the discovery of material binding peptides and their utilization in nanotechnology, which has brought new challenges and opportunities. Nowadays phage display is a versatile tool, important for the selection of ligands for proteins and peptides. This combinatorial approach has also been adapted over the past decade to select material-specific peptides. Screening and selection of such phage displayed material binding peptides has attracted great interest, in particular because of their use in nanotechnology. Phage display selected peptides are either synthesized independently or expressed on phage coat protein. Selected phage particles are subsequently utilized in the synthesis of nanoparticles, in the assembly of nanostructures on inorganic surfaces, and oriented protein immobilization as fusion partners of proteins. In this paper, we present an overview on the research conducted on this area. In this review we not only focus on the selection process, but also on molecular binding characterization and utilization of peptides as molecular linkers, molecular assemblers and material synthesizers.

Perfil antropométrico de jugadoras de balonmano femenino de élite

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A.B. Ramos-Angulo

2018-04-01

Full Text Available Resumen: Objetivo: Analizar las características antropométricas de 19 jugadoras de un equipo de balonmano sénior de élite. Método: Diecinueve jugadoras (n = 19 de balonmano pertenecientes a un equipo de División de Honor sénior formaron parte de este estudio. Se registraron diferentes medidas corporales para estudiar el perfil antropométrico: masa corporal, talla, pliegues cutáneos, perímetros y diámetros corporales, siguiendo el protocolo de la International Society for the Advancements of Kinanthropometry. Se obtuvo la composición corporal y el somatotipo de todas ellas. Resultados: Las jugadoras mostraron un peso medio (63.63 kg menor que el ideal para balonmano y una talla media de 168.2 cm, un somatotipo de 3.5, 4.6, 2.3 con dominancia de mesomorfia y un índice de masa corporal dentro del rango normal (22.4 kg/m2. Conclusión: Estos resultados proporcionan datos antropométricos normativos para jugadoras de balonmano de élite. El perfil predominante en nuestra muestra fue el endo-mesomórfico con valores medios similares a los reportados para mujeres deportistas de otras disciplinas. Los datos obtenidos indican que nuestra población posee características antropométricas similares a las descritas en otras jugadoras de balonmano, siendo ligeramente inferiores con respecto al peso, la altura y el índice de masa corporal. Abstract: Objective: To analyze the anthropometric characteristics of 19 female elite handball players from a elite senior team. Method: Nineteen (n=19 elite handball female players belonging to a senior team of Division of Honour participated in this study. Different body measurements were taken to study the anthropometric profile: body mass, skin folds, corporal perimeters and diameters, according to the International Society for the Advancements of Kinanthropometry protocol. Corporal composition and somatotype were obtained in every case. Results: Female players presented a lower average weight (63

Tetra­kis(aceto­nitrile)copper(I) hydrogen oxalate–oxalic acid–aceto­nitrile (1/0.5/0.5)

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Royappa, A. Timothy; Stepherson, Jacob R.; Vu, Oliver D.; Royappa, Andrew D.; Stern, Charlotte L.; Müller, Peter

2013-01-01

In the title compound, [Cu(CH3CN)4](C2HO4)·0.5C2H2O4·0.5CH3CN, the CuI ion is coordinated by the N atoms of four aceto­nitrile ligands in a slightly distorted tetra­hedral environment. The oxalic acid mol­ecule lies across an inversion center. The aceto­nitrile solvent mol­ecule is disordered across an inversion center and was refined with half occupancy. In the crystal, the hydrogen oxalate anions and oxalic acid mol­ecules are linked via O—H⋯O hydrogen bonds, forming chains along [010]. PMID:24098175

Photorefractive IR-spectrum composites prepared from polyimide and ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially coordinated triethylenediamine molecules

International Nuclear Information System (INIS)

Vannikov, A.V.; Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Tsivadze, A.Yu.

2006-01-01

Photoelectric, non-linear optical, and photorefractive properties of aromatic polyimine doped with ruthenium(II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules, (R 4 Pc)Ru(TED) 2 , where R 4 Pc 2- and TED denote 4,5,4',5',4'',5'',4''',5'''-tetrakis-(1,4,7,10,13- pentaoxatridecamethylene)phthalocyaninate ion and triethylenediamine molecule, respectively, were studied. It is established that supramolecular ensembles on the basis of the complex make an aromatic polyimide layer photoelectrically sensitive to 1064-nm Nd : YAG laser radiation, exhibit third-order susceptibility, and, consequently, impart photorefractive properties to the polymer layer at this wavelength [ru

Beneficios de la suplementación con L-carnitina en pacientes pediátricos hemodializados. Reporte de casos

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JA Martínez-Morales

2016-09-01

Full Text Available INTRODUCCIÓN: la mayoría de los pacientes pediátricos con insuficiente renal crónica desarrollan desnutrición y anemia. Para tratar esta última se administra eritropoyetina como tratamiento de elección, pero no se logra recuperar la situación nutricional del paciente, por lo que la L-carnitina es una alternativa que mejora el estado nutricional y, al mismo tiempo, disminuye la frecuencia de anemia. OBJETIVO: mejorar los parámetros bioquímicos y antropométricos después de la suplementación con L carnitina en pacientes pediátricos.  MATERIAL Y MÉTODOS: se realizó un estudio analítico y longitudinal, de una serie de casos en 25 participantes, ambos sexos, de 3 a 16 años de edad, con insuficiencia renal crónica y en tratamiento de hemodiálisis. Se les suministró L-carnitina por vía intravenosa (50 mg/ kg/sesión 30 minutos antes de terminar las sesiones de hemodiálisis, durante tres meses (36 sesiones. Antes y después de la maniobra se compararon algunos indicadores bioquímicos (hemoglobina, albumina, colesterol, triglicéridos, creatinina y antropométricos. Se realizó una comparación con T de Student y por proporciones (casos que mejoraron después de maniobra y la reducción del riesgo absoluto. RESULTADOS: la edad promedio de los casos fue 12.4 años (rango de 3 a 16 años. Al comparar los casos con T de Student se obtuvo una mejora significativa con la suplementación para el peso seco (p=0.004; índice de masa corporal (p=0.04; albúmina (p=0.02 y colesterol (p=0.003. Con el cálculo por proporciones de los casos que mejoraron con la maniobra se observó la reducción del riesgo atribuible en un rango de 12 a 68% de todas las variables de interés (hemoglobina, albúmina, colesterol, triglicéridos, peso seco e índice de masa corporal. CONCLUSIONES: la suplementación con L-carnitina intravenosa (50 mg/kg/sesión 30 minutos antes de terminar cada sesión de hemodiálisis, durante tres meses

Cadastro Ambiental Rural utilizando imagem de drone aerofotogramétrico

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João Edson Costa Ferreira da Silva

2017-07-01

Full Text Available O Cadastro Ambiental Rural (CAR é uma importante base de dados estratégica para a gestão ambiental do país. Este estudo tem como objetivo comparar a acurácia da imagem orbital disponibilizada para o CAR com uma ortofoto obtida com o drone aerofotogramétrico, tendo como parâmetro de incerteza o produto cartográfico obtido com estação total. A ortofoto apresentou melhor resultado em relação à imagem orbital. Ambas foram analisadas comparando áreas homólogas nas imagens, de diferentes tamanhos e posições, em ambos os produtos cartográficos. Tal resultado pode justificar a aquisição de um produto mais fidedigno para o controle ambiental no país, principalmente em pequenas áreas rurais, tendo em vista que a porção territorial é extensa e não homogênea.

Cyclic peptide therapeutics: past, present and future.

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Zorzi, Alessandro; Deyle, Kaycie; Heinis, Christian

2017-06-01

Cyclic peptides combine several favorable properties such as good binding affinity, target selectivity and low toxicity that make them an attractive modality for the development of therapeutics. Over 40 cyclic peptide drugs are currently in clinical use and around one new cyclic peptide drug enters the market every year on average. The vast majority of clinically approved cyclic peptides are derived from natural products, such as antimicrobials or human peptide hormones. New powerful techniques based on rational design and in vitro evolution have enabled the de novo development of cyclic peptide ligands to targets for which nature does not offer solutions. A look at the cyclic peptides currently under clinical evaluation shows that several have been developed using such techniques. This new source for cyclic peptide ligands introduces a freshness to the field, and it is likely that de novo developed cyclic peptides will be in clinical use in the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sequencing Cyclic Peptides by Multistage Mass Spectrometry

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Mohimani, Hosein; Yang, Yu-Liang; Liu, Wei-Ting; Hsieh, Pei-Wen; Dorrestein, Pieter C.; Pevzner, Pavel A.

2012-01-01

Some of the most effective antibiotics (e.g., Vancomycin and Daptomycin) are cyclic peptides produced by non-ribosomal biosynthetic pathways. While hundreds of biomedically important cyclic peptides have been sequenced, the computational techniques for sequencing cyclic peptides are still in their infancy. Previous methods for sequencing peptide antibiotics and other cyclic peptides are based on Nuclear Magnetic Resonance spectroscopy, and require large amount (miligrams) of purified materials that, for most compounds, are not possible to obtain. Recently, development of mass spectrometry based methods has provided some hope for accurate sequencing of cyclic peptides using picograms of materials. In this paper we develop a method for sequencing of cyclic peptides by multistage mass spectrometry, and show its advantages over single stage mass spectrometry. The method is tested on known and new cyclic peptides from Bacillus brevis, Dianthus superbus and Streptomyces griseus, as well as a new family of cyclic peptides produced by marine bacteria. PMID:21751357

Competition between bound and free peptides in an ELISA-based procedure that assays peptides derived from protein digests

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Pace Umberto

2006-05-01

Full Text Available Abstract Background We describe an ELISA-based method that can be used to identify and quantitate proteins in biological samples. In this method, peptides in solution, derived from proteolytic digests of the sample, compete with substrate-attached synthetic peptides for antibodies, also in solution, generated against the chosen peptides. The peptides used for the ELISA are chosen on the basis of their being (i products of the proteolytic (e.g. tryptic digestion of the protein to be identified and (ii unique to the target protein, as far as one can know from the published sequences. Results In this paper we describe the competition assay and we define the optimal conditions for the most effective assay. We have performed an analysis of the kinetics of interaction between the four components of the assay: the plastic substratum to which the peptide is bound, the bound peptide itself, the competing added peptide, and the antibody that is specific for the peptide and we compare the results of theoretical simulations to the actual data in some model systems. Conclusion The data suggest that the peptides bind to the plastic substratum in more than one conformation and that, once bound, the peptide displays different affinities for the antibody, depending on how it has bound to the plate

Comparative toxicity of tetra ethyl lead and lead oxide to earthworms, Eisenia fetida (Savigny)

International Nuclear Information System (INIS)

Venkateswara Rao, J.; Kavitha, P.; Padmanabha Rao, A.

2003-01-01

Leaded gasoline contains tetra ethyl lead (TEL) as an antiknocking agent, which produces major amounts of lead oxide in automobile exhaust along with traces of TEL. To minimize the lead contamination, methyl tertiary butyl ether (MTBE) is used as a substitute for producing unleaded gasoline. It has become increasingly apparent that young children are highly susceptible to the harmful effects of lead. Hence, a study was carried out to monitor lead toxicity in soil, using adult earthworms (Eisenia fetida, Savigny). Leaded gasoline (TEL) and lead oxide are 383- and 211-fold more toxic than unleaded gasoline (MTBE) in 7 days of exposure and 627- and 290-fold more toxic in 14 days, respectively. Results indicate that the presence of TEL in leaded gasoline and lead oxide has a significant effect on behavior, morphology, and histopathology of earthworms. Absorption of TEL into the tissues is comparatively less than that of lead oxide but toxic effects were severe. Rupture of the cuticle, extrusion of coelomic fluid and inflexible metameric segmentation were observed, causing desensitization of the posterior region leading to fragmentation in earthworms

Reconfigurable multiport EPON repeater

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Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

2009-11-01

An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

Reforma e crise do setor elétrico no período FHC

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José Goldenberg

2003-11-01

Full Text Available Este artigo aborda a reforma do setor elétrico brasileiro efetuada durante o governo Fernando Henrique Cardoso. Inicialmente, faz um rápido resumo da organização, do funcionamento e das dificuldades do setor antes da posse do presidente FHC. Descreve as principais linhas da proposta do governo e as críticas e alternativas ao modelo escolhido. Mostra, ainda, como a opção por uma rápida e profunda reforma do setor elétrico, calcada em experiências liberais de outros países, provocou uma grande desorganização na sua coordenação e planejamento. Essa situação foi agravada pela política econômica do governo, em particular, pela política cambial e pela restrição de investimentos das estatais. Como conseqüência, deu-se o racionamento de energia, o aumento de custos para os consumidores e um legado de empresas elétricas endividadas e dependentes do erário público.This paper analyzes the reforms that took place in the Brazilian electrical sector during Fernando Henrique Cardoso's government. Firstly, it presents a summary of the organization, functioning and difficulties encountered by the sector prior to his inauguration. It describes the main governmental proposals and the criticisms and alternatives to the chosen model. It shows how the option for a rapid and profound reform of the electricity system, based on liberal experiences in other countries caused great disruption on coordination and planning. This situation was worsened by the governmental economic policy, especially by its monetary exchange policy and by the restriction on investments of the state owned companies. This resulted in a rationing of energy, a heavy rate increase for consumers and a legacy of indebted electrical companies depending on public money.

Avaliação exergética de processos psicrométricos Exergetic evaluation of psychrometric processes

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Paulo Martins Leal

2000-12-01

Full Text Available Este trabalho teve como objetivo principal a aplicação da metodologia de avaliação dos processos psicrométricos utilizando os conceitos definidos pela combinação das 1ª e 2ª Leis da Termodinâmica, num sistema adaptado para a geração dos processos psicrométricos. Com equipamentos e instrumental adequados variaram-se, basicamente, em cada processo gerado pelo Sistema Gerador de Processos Psicrométricos (SIGEP, as vazões e as potências elétricas requeridas pelos diferentes sistemas de condicionamento do ar e as temperaturas de bulbo seco e de bulbo úmido de pontos estratégicos, dentro e fora do volume de controle, a fim de se efetuar as análises energéticas e exergética. Pode-se concluir que a metodologia de avaliação pela 1ª e 2ª Lei da Termodinâmica aplicada em processos psicrométricos é tecnicamente viável. Comprovou-se, ainda, através dos resultados obtidos, que a avaliação baseada exclusivamente na 1ª Lei da Termodinâmica (avaliação energética, em quase a totalidade dos processos gerados pelo SIGEP, é menos abrangente que a avaliação exergética. Pode-se concluir, também, que os equipamentos, acoplados ao SIGEP apresentaram um alto índice de irreversibilidade devido ao fato de terem sido dimensionados, exclusivamente, com a finalidade de atingir uma condição psicrométrica específica e não, de serem eficientes, do ponto de vista termodinâmico.This research had, as its principal objective, the application of the methodology to evaluate psychometric processes through the use of theory which combines the First and Second Principles of Thermodynamics into an adapted system of generating psychometric processes. With the Psychometric Processes System Generator (SIGEP and other appropriate equipment, where air flow and electrical power from different systems of air conditioning were the most important variables. It was feasible to obtain data of dry and wet bulb temperature, from different locations of

Vascular targeting with peptide libraries

Energy Technology Data Exchange (ETDEWEB)

Pasqualini, R. [La Jolla Cancer Research Center The Burnham Inst., La Jolla CA (United States)

1999-06-01

The authors have developed an 'in vivo' selection system in which phage capable of selective homing to different tissues are recovered from a phage display peptide library following intravenous administration. Using this strategy, they have isolate several organ and tumor-homing peptides. They have shown that each of those peptides binds of different receptors that are selectively expressed on the vasculature of the target tissue. The tumor-homing peptides bind to receptors that are up regulated in tumor angiogenic vasculature. Targeted delivery of doxorubicin to angiogenic vasculature using these peptides in animals models decrease toxicity and increased the therapeutic efficacy of the drug. Vascular targeting may facilitate the development of other treatment strategies that rely on inhibition of angio genesis and lead to advances to extend the potential for targeting of drugs, genes and radionuclides in the context of many diseases.

Natriuretic peptides and cerebral hemodynamics

DEFF Research Database (Denmark)

Guo, Song; Barringer, Filippa; Zois, Nora Elisabeth

2014-01-01

Natriuretic peptides have emerged as important diagnostic and prognostic tools for cardiovascular disease. Plasma measurement of the bioactive peptides as well as precursor-derived fragments is a sensitive tool in assessing heart failure. In heart failure, the peptides are used as treatment...... in decompensated disease. In contrast, their biological effects on the cerebral hemodynamics are poorly understood. In this mini-review, we summarize the hemodynamic effects of the natriuretic peptides with a focus on the cerebral hemodynamics. In addition, we will discuss its potential implications in diseases...... where alteration of the cerebral hemodynamics plays a role such as migraine and acute brain injury including stroke. We conclude that a possible role of the peptides is feasible as evaluated from animal and in vitro studies, but more research is needed in humans to determine the precise response...

Selective peptide bond hydrolysis of cysteine peptides in the presence of Ni(II) ions.

Science.gov (United States)

Protas, Anna Maria; Bonna, Arkadiusz; Kopera, Edyta; Bal, Wojciech

2011-01-01

Recently, we described a sequence-specific R1-(Ser/Thr) peptide bond hydrolysis reaction in peptides of a general sequence R1-(Ser/Thr)-Xaa-His-Zaa-R, which occurs in the presence of Ni(II) ions [A. Krężel, E. Kopera, A. M. Protas, A. Wysłouch-Cieszyńska, J. Poznański, W. Bal, J. Am. Chem. Soc. 132 (2010) 3355-3366]. In this study we explored the possibility of substituting the Ser/Thr and the His residues, necessary for the reaction to occur according to the Ni(II)-assisted acyl shift reaction mechanism, with Cys residues. We tested this concept by synthesizing three homologous peptides: R1-Ser-Arg-Cys-Trp-R2, R1-Cys-Arg-His-Trp-R2, and R1-Cys-Arg-Cys-Trp-R2, and the R1-Ser-Arg-His-Trp-R2 peptide as comparator (R1 and R2 were CH3CO-Gly-Ala and Lys-Phe-Leu-NH2, respectively). We studied their hydrolysis in the presence of Ni(II) ions, under anaerobic conditions and in the presence of TCEP as a thiol group antioxidant. We measured hydrolysis rates using HPLC and identified products of reaction using electrospray mass spectrometry. Potentiometry and UV-vis spectroscopy were used to assess Ni(II) complexation. We demonstrated that Ni(II) is not compatible with the Cys substitution of the Ser/Thr acyl acceptor residue, but the substitution of the Ni(II) binding His residue with a Cys yields a peptide susceptible to Ni(II)-related hydrolysis. The relatively high activity of the R1-Ser-Arg-Cys-Trp-R2 peptide at pH 7.0 suggests that this peptide and its Cys-containing analogs might be useful in practical applications of Ni(II)-dependent peptide bond hydrolysis. Copyright © 2010 Elsevier Inc. All rights reserved.

Chemical methods for peptide and protein production.

Science.gov (United States)

Chandrudu, Saranya; Simerska, Pavla; Toth, Istvan

2013-04-12

Since the invention of solid phase synthetic methods by Merrifield in 1963, the number of research groups focusing on peptide synthesis has grown exponentially. However, the original step-by-step synthesis had limitations: the purity of the final product decreased with the number of coupling steps. After the development of Boc and Fmoc protecting groups, novel amino acid protecting groups and new techniques were introduced to provide high quality and quantity peptide products. Fragment condensation was a popular method for peptide production in the 1980s, but unfortunately the rate of racemization and reaction difficulties proved less than ideal. Kent and co-workers revolutionized peptide coupling by introducing the chemoselective reaction of unprotected peptides, called native chemical ligation. Subsequently, research has focused on the development of novel ligating techniques including the famous click reaction, ligation of peptide hydrazides, and the recently reported α-ketoacid-hydroxylamine ligations with 5-oxaproline. Several companies have been formed all over the world to prepare high quality Good Manufacturing Practice peptide products on a multi-kilogram scale. This review describes the advances in peptide chemistry including the variety of synthetic peptide methods currently available and the broad application of peptides in medicinal chemistry.

Toxins and antimicrobial peptides: interactions with membranes

Science.gov (United States)

Schlamadinger, Diana E.; Gable, Jonathan E.; Kim, Judy E.

2009-08-01

The innate immunity to pathogenic invasion of organisms in the plant and animal kingdoms relies upon cationic antimicrobial peptides (AMPs) as the first line of defense. In addition to these natural peptide antibiotics, similar cationic peptides, such as the bee venom toxin melittin, act as nonspecific toxins. Molecular details of AMP and peptide toxin action are not known, but the universal function of these peptides to disrupt cell membranes of pathogenic bacteria (AMPs) or a diverse set of eukaryotes and prokaryotes (melittin) is widely accepted. Here, we have utilized spectroscopic techniques to elucidate peptide-membrane interactions of alpha-helical human and mouse AMPs of the cathelicidin family as well as the peptide toxin melittin. The activity of these natural peptides and their engineered analogs was studied on eukaryotic and prokaryotic membrane mimics consisting of resistant pathogens.

Natriuretic peptides in cardiometabolic regulation and disease

DEFF Research Database (Denmark)

Zois, Nora E; Bartels, Emil D; Hunter, Ingrid

2014-01-01

decade. Dysregulation of the natriuretic peptide system has been associated with obesity, glucose intolerance, type 2 diabetes mellitus, and essential hypertension. Moreover, the natriuretic peptides have been implicated in the protection against atherosclerosis, thrombosis, and myocardial ischaemia. All...... these conditions can coexist and potentially lead to heart failure, a syndrome associated with a functional natriuretic peptide deficiency despite high circulating concentrations of immunoreactive peptides. Therefore, dysregulation of the natriuretic peptide system, a 'natriuretic handicap', might be an important...... factor in the initiation and progression of metabolic dysfunction and its accompanying cardiovascular complications. This Review provides a summary of the natriuretic peptide system and its involvement in these cardiometabolic conditions. We propose that these peptides might have an integrating role...

Peptide aldehyde inhibitors of bacterial peptide deformylases.

Science.gov (United States)

Durand, D J; Gordon Green, B; O'Connell, J F; Grant, S K

1999-07-15

Bacterial peptide deformylases (PDF, EC 3.5.1.27) are metalloenzymes that cleave the N-formyl groups from N-blocked methionine polypeptides. Peptide aldehydes containing a methional or norleucinal inhibited recombinant peptide deformylase from gram-negative Escherichia coli and gram-positive Bacillus subtilis. The most potent inhibitor was calpeptin, N-CBZ-Leu-norleucinal, which was a competitive inhibitor of the zinc-containing metalloenzymes, E. coli and B. subtilis PDF with Ki values of 26.0 and 55.6 microM, respectively. Cobalt-substituted E. coli and B. subtilis deformylases were also inhibited by these aldehydes with Ki values for calpeptin of 9.5 and 12.4 microM, respectively. Distinct spectral changes were observed upon binding of calpeptin to the Co(II)-deformylases, consistent with the noncovalent binding of the inhibitor rather than the formation of a covalent complex. In contrast, the chelator 1,10-phenanthroline caused the time-dependent inhibition of B. subtilis Co(II)-PDF activity with the loss of the active site metal. The fact that calpeptin was nearly equipotent against deformylases from both gram-negative and gram-positive bacterial sources lends further support to the idea that a single deformylase inhibitor might have broad-spectrum antibacterial activity. Copyright 1999 Academic Press.

Símbolos geométricos en la cerámica de Izapa, Chiapas

Directory of Open Access Journals (Sweden)

Alla Kolpakova

2009-07-01

Full Text Available El artículo aborda el conjunto de símbolos geométricos (puntos, líneas, triángulos, círculos, etcétera elaborados sobre la cerámica proveniente del sitio arqueológico de Izapa, Chiapas. Dichos símbolos tienen una importancia especial para el entendimiento de la historia de los orígenes de la civilización en el sureste de Mesoamérica. El propósito final es dilucidar, con auxilio de diversas fuentes comparativas, los posibles significados “básicos” que los antiguos alfareros de Izapa otorgaban a los símbolos que imprimían en su cerámica.

Peptide-LNA oligonucleotide conjugates

DEFF Research Database (Denmark)

Astakhova, I Kira; Hansen, Lykke Haastrup; Vester, Birte

2013-01-01

properties, peptides were introduced into oligonucleotides via a 2'-alkyne-2'-amino-LNA scaffold. Derivatives of methionine- and leucine-enkephalins were chosen as model peptides of mixed amino acid content, which were singly and doubly incorporated into LNA/DNA strands using highly efficient copper......(i)-catalyzed azide-alkyne cycloaddition (CuAAC) "click" chemistry. DNA/RNA target binding affinity and selectivity of the resulting POCs were improved in comparison to LNA/DNA mixmers and unmodified DNA controls. This clearly demonstrates that internal attachment of peptides to oligonucleotides can significantly...

Screening and Identification of Peptides Specifically Targeted to Gastric Cancer Cells from a Phage Display Peptide Library

Science.gov (United States)

Sahin, Deniz; Taflan, Sevket Onur; Yartas, Gizem; Ashktorab, Hassan; Smoot, Duane T

2018-04-25

Background: Gastric cancer is the second most common cancer among the malign cancer types. Inefficiency of traditional techniques both in diagnosis and therapy of the disease makes the development of alternative and novel techniques indispensable. As an alternative to traditional methods, tumor specific targeting small peptides can be used to increase the efficiency of the treatment and reduce the side effects related to traditional techniques. The aim of this study is screening and identification of individual peptides specifically targeted to human gastric cancer cells using a phage-displayed peptide library and designing specific peptide sequences by using experimentally-eluted peptide sequences. Methods: Here, MKN-45 human gastric cancer cells and HFE-145 human normal gastric epithelial cells were used as the target and control cells, respectively. 5 rounds of biopannning with a phage display 12-peptide library were applied following subtraction biopanning with HFE-145 control cells. The selected phage clones were established by enzyme-linked immunosorbent assay and immunofluorescence detection. We first obtain random phage clones after five biopanning rounds, determine the binding levels of each individual clone. Then, we analyze the frequencies of each amino acid in best binding clones to determine positively overexpressed amino acids for designing novel peptide sequences. Results: DE532 (VETSQYFRGTLS) phage clone was screened positive, showing specific binding on MKN-45 gastric cancer cells. DE-Obs (HNDLFPSWYHNY) peptide, which was designed by using amino acid frequencies of experimentally selected peptides in the 5th round of biopanning, showed specific binding in MKN-45 cells. Conclusion: Selection and characterization of individual clones may give us specifically binding peptides, but more importantly, data extracted from eluted phage clones may be used to design theoretical peptides with better binding properties than even experimentally selected ones

Properties of uncharged water-soluble tetra({omega}-methoxypolyethyleneoxy)phthalocyanine free base: Viable switching of the optical response by means of H{sub 3}O{sup +} ions

Energy Technology Data Exchange (ETDEWEB)

Mineo, Placido [Department of Chemistry, University of Catania and INSTM UdR of Catania, Viale Andrea Doria 6, 95125 Catania (Italy); Istituto per i Processi Chimico Fisici - CNR, Viale Ferdinando Stagno D' Alcontres, 37, 98158 Messina (Italy); Lupo, Fabio; Fragala, Ignazio; Scamporrino, Emilio [Department of Chemistry, University of Catania and INSTM UdR of Catania, Viale Andrea Doria 6, 95125 Catania (Italy); Gulino, Antonino, E-mail: agulino@unict.it [Department of Chemistry, University of Catania and INSTM UdR of Catania, Viale Andrea Doria 6, 95125 Catania (Italy)

2012-02-15

An uncharged water-soluble tetra ({omega}-methoxypolyethyleneoxy)phthalocyanine was characterized by MALDI-TOF mass spectrometry, UV-vis and luminescence measurements. The polyether substituents render water soluble this uncharged phthalocyanine. Relevant changes are observed in emission measurements upon protonation. The phthalocyanine free base and its protonated forms can be switched alternating H{sub 3}O{sup +} and OH{sup -} ions as inputs, being the intensity of the luminescence spectra the output. Binary codes 1 or 0 can be assigned to the high luminescent phthalocyanine free base state or to the low luminescent protonated state, respectively. The read-out procedure is fast and the system is reversible. In addition, the exploiting of the luminescent properties of the present water soluble phthalocyanine could be of relevance also for biological applications (photosensitizers for the photodynamic therapy). Highlights: Black-Right-Pointing-Pointer An uncharged water soluble tetra ({omega}-methoxypolyethyleneoxy)phthalocyanine was characterized. Black-Right-Pointing-Pointer Phthalocyanine protonation changes the luminescence output. Black-Right-Pointing-Pointer The system can be switched alternating H{sub 3}O{sup +} and OH{sup -} as inputs. Black-Right-Pointing-Pointer The read-out procedure is fast and reversible. Black-Right-Pointing-Pointer Binary codes are assigned to the high and low luminescent states, respectively.

Valoración del dolor en el paciente pediátrico hospitalizado. Revisión narrativa

OpenAIRE

Reyes Corrales, Inés de los

2017-01-01

Trabajo fin de grado en Enfermería El dolor es definido por la IASP como una “experiencia sensorial y emocional desagradable, asociada a una lesión tisular real o potencial” Es importante que este sea considerado, valorado y tratado, independientemente de la edad, cultura y estado clínico. Objetivo: Conocer la evidencia disponible a cerca de las herramientas existentes para la evaluación del dolor en el paciente pediátrico hospitalizado. Material y método: Se realizó una ...

Peptide YY receptors in the brain

International Nuclear Information System (INIS)

Inui, A.; Oya, M.; Okita, M.

1988-01-01

Radiolabelled ligand binding studies demonstrated that specific receptors for peptide YY are present in the porcine as well as the canine brains. Peptide YY was bound to brain tissue membranes via high-affinity (dissociation constant, 1.39 X 10(-10)M) and low-affinity (dissociation constant, 3.72 X 10(-8)M) components. The binding sites showed a high specificity for peptide YY and neuropeptide Y, but not for pancreatic polypeptide or structurally unrelated peptides. The specific activity of peptide YY binding was highest in the hippocampus, followed by the pituitary gland, the hypothalamus, and the amygdala of the porcine brain, this pattern being similarly observed in the canine brain. The results suggest that peptide YY and neuropeptide Y may regulate the function of these regions of the brain through interaction with a common receptor site

Intracellular Signalling by C-Peptide

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Claire E. Hills

2008-01-01

Full Text Available C-peptide, a cleavage product of the proinsulin molecule, has long been regarded as biologically inert, serving merely as a surrogate marker for insulin release. Recent findings demonstrate both a physiological and protective role of C-peptide when administered to individuals with type I diabetes. Data indicate that C-peptide appears to bind in nanomolar concentrations to a cell surface receptor which is most likely to be G-protein coupled. Binding of C-peptide initiates multiple cellular effects, evoking a rise in intracellular calcium, increased PI-3-kinase activity, stimulation of the Na+/K+ ATPase, increased eNOS transcription, and activation of the MAPK signalling pathway. These cell signalling effects have been studied in multiple cell types from multiple tissues. Overall these observations raise the possibility that C-peptide may serve as a potential therapeutic agent for the treatment or prevention of long-term complications associated with diabetes.

Dados abertos conectados e gestão do conhecimento: estudos de caso cientométricos em uma universidade brasileira

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Sandro Rautenberg

Full Text Available RESUMO Este artigo se baseia na relação de três conceitos: Gestão do Conhecimento, Cientometria e Dados Abertos Conectados. No contexto das universidades, objetiva-se discutir a promoção da Gestão do Conhecimento institucional amparada por Dados Abertos Conectados advindos do domínio da Cientometria. Para tanto, baseando-se nos preceitos da Web Semântica, pontualmente, no processo metodológico Linked Data Lifecycle, duas bases de dados são abertamente mantidas na Web de Dados: a o histórico do Índice Qualis (2005-2015; e b um conjunto de registros de publicações em periódicos extraído da Plataforma Lattes. Como resultado, três estudos de caso reais são desenvolvidos, os quais consumem, relacionam e exploram os dados dessas fontes. Mediante os estudos realizados, conclui-se que as práticas relativas aos Dados Abertos Conectados contribuem na formação de bases de conhecimento institucionais, podendo suportar diversos estudos bibliométricos e cientométricos ou as atividades aderentes à Gestão do Conhecimento universidades brasileiras.

Estudos métricos da informação: primeiras aproximações Metric studies of information: first approaches

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Daisy Pires Noronha

2008-01-01

Full Text Available Apresentam-se alguns conceitos e considerações fundamentais dos estudos métricos da informação e os principais métodos e técnicas utilizadas, como a bibliometria, cienciometria, informetria, webmetria, patentometria e biblioteconometria. Discute-se o ciclo de comunicação científica, destacando-se os principais indicadores de input (insumo e output (produto, assim como, a importância da publicação dos resultados da pesquisa científica e do processo de avaliação pelos pares. Comentam-se algumas características e aplicações das leis bibliométricas e de outros recursos utilizados nos estudos métricos da informação.Concepts and basic considerations about metric studies of information, and the main methods and techniques, such as bibliometrics, scientometrics, informetrics,webmetrics, patentometrics and librametrics are presented. The scholarly communication cycle, specially the main input (resources and output (product indicators, as well as the importance of the publication of scientific research results and the peer review process are discussed. Some characteristics and applications of bibliometric laws, and the resources used for metrics studies of information arecommented.

A novel chimeric peptide with antimicrobial activity.

Science.gov (United States)

Alaybeyoglu, Begum; Akbulut, Berna Sariyar; Ozkirimli, Elif

2015-04-01

Beta-lactamase-mediated bacterial drug resistance exacerbates the prognosis of infectious diseases, which are sometimes treated with co-administration of beta-lactam type antibiotics and beta-lactamase inhibitors. Antimicrobial peptides are promising broad-spectrum alternatives to conventional antibiotics in this era of evolving bacterial resistance. Peptides based on the Ala46-Tyr51 beta-hairpin loop of beta-lactamase inhibitory protein (BLIP) have been previously shown to inhibit beta-lactamase. Here, our goal was to modify this peptide for improved beta-lactamase inhibition and cellular uptake. Motivated by the cell-penetrating pVEC sequence, which includes a hydrophobic stretch at its N-terminus, our approach involved the addition of LLIIL residues to the inhibitory peptide N-terminus to facilitate uptake. Activity measurements of the peptide based on the 45-53 loop of BLIP for enhanced inhibition verified that the peptide was a competitive beta-lactamase inhibitor with a K(i) value of 58 μM. Incubation of beta-lactam-resistant cells with peptide decreased the number of viable cells, while it had no effect on beta-lactamase-free cells, indicating that this peptide had antimicrobial activity via beta-lactamase inhibition. To elucidate the molecular mechanism by which this peptide moves across the membrane, steered molecular dynamics simulations were carried out. We propose that addition of hydrophobic residues to the N-terminus of the peptide affords a promising strategy in the design of novel antimicrobial peptides not only against beta-lactamase but also for other intracellular targets. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

Trauma craniano violento pediátrico: uma revisão da literatura

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Nahara R.L. Lopes

2013-10-01

Full Text Available OBJETIVO: Fornecer uma revisão de literatura científica sobre trauma craniano violento pediátrico enquanto forma de maus-tratos físicos contra bebês e crianças, ressaltando prevalência, sinais e sintomas, consequências, fatores de risco para sua ocorrência e, principalmente, estratégias de prevenção. FONTES DOS DADOS: Revisão nas bases de dados MEDLINE, SciELO, LILACS e Web of Science no período de 2001 a 2012 utilizando os termos "síndrome do bebê sacudido" e "trauma craniano violento" em inglês, espanhol e português. SÍNTESE DOS DADOS: O trauma craniano violento é definido como a lesão ao crânio ou ao conteúdo intracraniano de um bebê ou criança menor de cinco anos devido a um impacto brusco intencional e/ou a uma sacudida violenta. Ocorre principalmente com bebês e crianças menores de um ano de idade, e pode resultar em consequências graves, desde deficiências físicas ou mentais até a morte. Apesar de haver sinais específicos para esta forma de maus-tratos, eles podem se confundir com doenças comuns em crianças ou traumas cranianos acidentais, sendo imprescindível o preparo clínico dos profissionais envolvidos na avaliação dos casos para o diagnóstico correto. As estratégias de prevenção devem incluir tanto a identificação precoce dos casos, como a educação parental sobre o desenvolvimento infantil, especialmente sobre o padrão de choro do bebê. CONCLUSÕES: Considerando a gravidade do trauma craniano violento pediátrico, é fundamental que estratégias de prevenção sejam implementadas e avaliadas no contexto brasileiro. Sugere-se que indicadores de sua incidência sejam pesquisados nacionalmente.

Peptides: Production, bioactivity, functionality, and applications

DEFF Research Database (Denmark)

Hajfathalian, Mona; Ghelichi, Sakhi; García Moreno, Pedro Jesús

2017-01-01

Production of peptides with various effects from proteins of different sources continues to receive academic attention. Researchers of different disciplines are putting increasing efforts to produce bioactive and functional peptides from different sources such as plants, animals, and food industry...... by-products. The aim of this review is to introduce production methods of hydrolysates and peptides and provide a comprehensive overview of their bioactivity in terms of their effects on immune, cardiovascular, nervous, and gastrointestinal systems. Moreover, functional and antioxidant properties...... of hydrolysates and isolated peptides are reviewed. Finally, industrial and commercial applications of bioactive peptides including their use in nutrition and production of pharmaceuticals and nutraceuticals are discussed....

Análisis de transición dinámica: un enfoque no paramétrico aplicado a la región centro de México (1988-2003)

OpenAIRE

Borrayo López, Rafael; Castañeda Arriaga, Juan Manuel

2011-01-01

La teoría del crecimiento (neoclásica, endógena y de la nueva geografía económica) y el desarrollo de nuevas técnicas computacionales han fertilizado el campo de conocimiento del análisis económico-espacial y, más recientemente, el uso de métodos paramétricos se ha complementado con el desarrollo de métodos semi y no paramétricos que han potenciado el análisis de procesos de crecimiento. Desde esta perspectiva, en este estudio se realiza un análisis de dinámica de la distribución (ADD) de una...

Chemical Methods for Peptide and Protein Production

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Istvan Toth

2013-04-01

Full Text Available Since the invention of solid phase synthetic methods by Merrifield in 1963, the number of research groups focusing on peptide synthesis has grown exponentially. However, the original step-by-step synthesis had limitations: the purity of the final product decreased with the number of coupling steps. After the development of Boc and Fmoc protecting groups, novel amino acid protecting groups and new techniques were introduced to provide high quality and quantity peptide products. Fragment condensation was a popular method for peptide production in the 1980s, but unfortunately the rate of racemization and reaction difficulties proved less than ideal. Kent and co-workers revolutionized peptide coupling by introducing the chemoselective reaction of unprotected peptides, called native chemical ligation. Subsequently, research has focused on the development of novel ligating techniques including the famous click reaction, ligation of peptide hydrazides, and the recently reported a-ketoacid-hydroxylamine ligations with 5-oxaproline. Several companies have been formed all over the world to prepare high quality Good Manufacturing Practice peptide products on a multi-kilogram scale. This review describes the advances in peptide chemistry including the variety of synthetic peptide methods currently available and the broad application of peptides in medicinal chemistry.

Insulin and C-peptide in human brain neurons (insulin/C-peptide/brain peptides/immunohistochemistry/radioimmunoassay)

International Nuclear Information System (INIS)

Dorn, A.; Bernstein, H.G.; Rinne, A.; Hahn, H.J.; Ziegler, M.

1983-01-01

The regional distribution and cellular localization of insulin and C-peptide immunoreactivities were studied in human cadaver brains using the indirect immunofluorescence method, the peroxidase-antiperoxidase technique, and radioimmunoassay. Products of the immune reactions to both polypeptides were observed in most nerve cells in all areas of the brain examined. Immunostaining was mainly restricted to the cell soma and proximal dendrites. Radioimmunoassay revealed that human brain contains insulin and C-peptide in concentrations much higher than the blood, the highest being in the hypothalamus. These findings support the hypothesis that the 'brain insulin' is - at least in part - produced in the CNS. (author)

Prevalência de doenças crônicas em pacientes geriátricos

OpenAIRE

Pinelli, Lígia Antunes Pereira et al.

2005-01-01

Introdução: O conhecimento do paciente geriátrico como um todo e não somente de sua boca é de extrema importância. Noções de patofisiologia, das condições crônicas que acometem esses pacientes e da farmacologia das drogas utilizadas serão úteis ao profissional do futuro, isso porque o número de idosos vem crescendo em todo o mundo, mostrando um aumento na demanda odontológica dessa parcela da população. Objetivo: o objetivo deste trabalho foi avaliar as doenças crônicas que mais acometem os i...

Ejercicios resistidos, parámetros hematológicos, virológicos y perfil antropométrico en personas que viven con VIH/SIDA

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I.K. dos Santos

2016-09-01

Conclusiones: Se concluye que al participar en un programa de ejercicios de fuerza, las personas que viven con VIH/ SIDA obtuvieron mejorías en los parámetros hematológicos, virológicos y en su perfil antropométrico.

Toward Peptide Nucleic Acid (PNA) Directed Peptide Translation Using Ester Based Aminoacyl Transfer

DEFF Research Database (Denmark)

Singhal, Abhishek; Bagnacani, Valentina; Corradini, Roberto

2014-01-01

Peptide synthesis is a fundamental feature of life. However, it still remains unclear how the contemporary translation apparatus evolved from primitive prebiotic systems and at which stage of the evolution peptide synthesis emerged. Using simple molecular architectures, in which aminoacyl transfe...

Towards generation of bioactive peptides from meat industry waste proteins: Generation of peptides using commercial microbial proteases.

Science.gov (United States)

Ryder, Kate; Bekhit, Alaa El-Din; McConnell, Michelle; Carne, Alan

2016-10-01

Five commercially available food-grade microbial protease preparations were evaluated for their ability to hydrolyse meat myofibrillar and connective tissue protein extracts to produce bioactive peptides. A bacterial-derived protease (HT) extensively hydrolysed both meat protein extracts, producing peptide hydrolysates with significant in vitro antioxidant and ACE inhibitor activities. The hydrolysates retained bioactivity after simulated gastrointestinal hydrolysis challenge. Gel permeation chromatography sub-fractionation of the crude protein hydrolysates showed that the smaller peptide fractions exhibited the highest antioxidant and ACE inhibitor activities. OFFGEL electrophoresis of the small peptides of both hydrolysates showed that low isoelectric point peptides had antioxidant activity; however, no consistent relationship was observed between isoelectric point and ACE inhibition. Cell-based assays indicated that the hydrolysates present no significant cytotoxicity towards Vero cells. The results indicate that HT protease hydrolysis of meat myofibrillar and connective tissue protein extracts produces bioactive peptides that are non-cytotoxic, should be stable in the gastrointestinal tract and may contain novel bioactive peptide sequences. Copyright © 2016 Elsevier Ltd. All rights reserved.

Peptide-membrane Interactions by Spin-labeling EPR

Science.gov (United States)

Smirnova, Tatyana I.; Smirnov, Alex I.

2016-01-01

Site-directed spin labeling (SDSL) in combination with Electron Paramagnetic Resonance (EPR) spectroscopy is a well-established method that has recently grown in popularity as an experimental technique, with multiple applications in protein and peptide science. The growth is driven by development of labeling strategies, as well as by considerable technical advances in the field, that are paralleled by an increased availability of EPR instrumentation. While the method requires an introduction of a paramagnetic probe at a well-defined position in a peptide sequence, it has been shown to be minimally destructive to the peptide structure and energetics of the peptide-membrane interactions. In this chapter, we describe basic approaches for using SDSL EPR spectroscopy to study interactions between small peptides and biological membranes or membrane mimetic systems. We focus on experimental approaches to quantify peptide-membrane binding, topology of bound peptides, and characterize peptide aggregation. Sample preparation protocols including spin-labeling methods and preparation of membrane mimetic systems are also described. PMID:26477253

Peptide pool immunization and CD8+ T cell reactivity

DEFF Research Database (Denmark)

Rasmussen, Susanne B; Harndahl, Mikkel N; Buus, Anette Stryhn

2013-01-01

Mice were immunized twice with a pool of five peptides selected among twenty 8-9-mer peptides for their ability to form stable complexes at 37°C with recombinant H-2K(b) (half-lives 10-15h). Vaccine-induced immunity of splenic CD8(+) T cells was studied in a 24h IFNγ Elispot assay. Surprisingly...... peptides induced normal peptide immunity i.e. the specific T cell reactivity in the Elispot culture was strictly dependent on exposure to the immunizing peptide ex vivo. However, immunization with two of the peptides, a VSV- and a Mycobacterium-derived peptide, resulted in IFNγ spot formation without...... peptide in the Elispot culture. Immunization with a mixture of the VSV-peptide and a "normal" peptide also resulted in IFNγ spot formation without addition of peptide to the assay culture. Peptide-tetramer staining of CD8(+) T cells from mice immunized with a mixture of VSV-peptide and "normal" peptide...

Decomposition of tetra-alkylammonium thiomolybdates characterised by thermoanalysis and mass spectrometry

International Nuclear Information System (INIS)

Poisot, M.; Bensch, W.; Fuentes, S.; Alonso, G.

2006-01-01

The decomposition pattern of tetraalkyl-tetrathiomolybdates with general formula (R 4 N) 2 MoS 4 (with R increasing from methyl to heptyl) was determined by means of differential thermal analysis (DTA), thermogravimetric analysis (TGA) and mass spectroscopy (MS) techniques. The complexity of thermal decomposition reactions increases with the size of the R 4 N group. Prior to decomposition at least one phase transition seems to occur in all complexes. The onset of thermal reactions was also a function of the tetra-alkylammonium precursor. All compounds decompose without forming sulfur rich MoS 2+x intermediates. For R = methyl to pentyl precursors the MoS 2 produced was nearly stoichiometric, however for R = hexyl and heptyl the S content was significantly reduced with a Mo:S ratio of about 1.5. The carbon and hydrogen residual contents in the product increased with the number of C atoms in R 4 N; for N contamination no clear trend was obvious. SEM images show that the formation of macro-pores was also a function of the alkyl group in R 4 N. The MoS 2 materials obtained show a sponge-like morphology. Results of DSC experiments in combination with in situ X-ray diffraction also revealed the complex thermal behavior of (R 4 N) 2 MoS 4 materials; reversible and irreversible phase transitions and glass-like transformations were identified in the low temperature range (35-140 deg. C), before the onset of decomposition

Peptides for functionalization of InP semiconductors.

Science.gov (United States)

Estephan, Elias; Saab, Marie-belle; Larroque, Christian; Martin, Marta; Olsson, Fredrik; Lourdudoss, Sebastian; Gergely, Csilla

2009-09-15

The challenge is to achieve high specificity in molecular sensing by proper functionalization of micro/nano-structured semiconductors by peptides that reveal specific recognition for these structures. Here we report on surface modification of the InP semiconductors by adhesion peptides produced by the phage display technique. An M13 bacteriophage library has been used to screen 10(10) different peptides against the InP(001) and the InP(111) surfaces to finally isolate specific peptides for each orientation of the InP. MALDI-TOF/TOF mass spectrometry has been employed to study real affinity of the peptide towards the InP surfaces. The peptides serve for controlled placement of biotin onto InP to bind then streptavidin. Our Atomic Force Microscopy study revealed a total surface coverage of molecules when the InP surface was functionalized by its specific biotinylated peptide (YAIKGPSHFRPS). Finally, fluorescence microscopy has been employed to demonstrate the preferential attachment of the peptide onto a micro-patterned InP surface. Use of substrate specific peptides could present an alternative solution for the problems encountered in the actually existing sensing methods and molecular self-assembly due to the unwanted unspecific interactions.

The optimization of peptide cargo bound to MHC class I molecules by the peptide-loading complex.

Science.gov (United States)

Elliott, Tim; Williams, Anthony

2005-10-01

Major histocompatibility complex (MHC) class I complexes present peptides from both self and foreign intracellular proteins on the surface of most nucleated cells. The assembled heterotrimeric complexes consist of a polymorphic glycosylated heavy chain, non-polymorphic beta(2) microglobulin, and a peptide of typically nine amino acids in length. Assembly of the class I complexes occurs in the endoplasmic reticulum and is assisted by a number of chaperone molecules. A multimolecular unit termed the peptide-loading complex (PLC) is integral to this process. The PLC contains a peptide transporter (transporter associated with antigen processing), a thiooxido-reductase (ERp57), a glycoprotein chaperone (calreticulin), and tapasin, a class I-specific chaperone. We suggest that class I assembly involves a process of optimization where the peptide cargo of the complex is edited by the PLC. Furthermore, this selective peptide loading is biased toward peptides that have a longer off-rate from the assembled complex. We suggest that tapasin is the key chaperone that directs this action of the PLC with secondary contributions from calreticulin and possibly ERp57. We provide a framework model for how this may operate at the molecular level and draw parallels with the proposed mechanism of action of human leukocyte antigen-DM for MHC class II complex optimization.

O papel do polimorfismo funcional VNTR da região promotora do gene MAOA nos transtornos psiquiátricos

Directory of Open Access Journals (Sweden)

Sílvia A. Nishioka

2011-01-01

Full Text Available INTRODUÇÃO: Muitos estudos têm investigado a associação do polimorfismo VNTR (número variável de repetições em série localizado na região promotora do gene da enzima monoamina oxidase A (MAOA com alterações no comportamento humano e em diversos transtornos psiquiátricos. OBJETIVO: O objetivo do presente trabalho foi revisar a literatura sobre a participação desse polimorfismo funcional na modulação do comportamento humano para o desenvolvimento dos transtornos psiquiátricos. MÉTODO: A pesquisa foi realizada na literatura em inglês, de janeiro de 1998 a junho de 2009, disponível no Medline, Embase, Web of Science e na base de dados PsycInfo, utilizando os seguintes termos: "MAOA e comportamento humano" e "MAOA e psiquiatria". RESULTADOS: Foram encontrados 3.873 estudos. Desses, 109 foram selecionados e incluídos na revisão. Encontrou-se associação de alelos de baixa atividade do VNTR com transtorno de personalidade antissocial, transtorno de conduta, transtorno de déficit de atenção e hiperatividade, jogo patológico e dependência de substâncias. Alelos da alta atividade da MAOA foram associados a depressão, ansiedade, neuroticismo e anorexia nervosa. Não se encontrou associação entre polimorfismos da MAOA e esquizofrenia e transtorno bipolar. CONCLUSÃO: Os principais achados dão suporte ao papel do polimorfismo VNTR da região promotora do gene da MAOA em alguns transtornos psiquiátricos, apesar das divergências encontradas devidas às dificuldades metodológicas de estudos em genética. De modo geral, os estudos associam os alelos de baixa atividade da MAOA com comportamentos impulsivos e agressivos ("comportamentos hiperativos", enquanto os alelos de alta atividade do gene são mais associados a "comportamentos hipoativos".

Chemical reactions directed Peptide self-assembly.

Science.gov (United States)

Rasale, Dnyaneshwar B; Das, Apurba K

2015-05-13

Fabrication of self-assembled nanostructures is one of the important aspects in nanoscience and nanotechnology. The study of self-assembled soft materials remains an area of interest due to their potential applications in biomedicine. The versatile properties of soft materials can be tuned using a bottom up approach of small molecules. Peptide based self-assembly has significant impact in biology because of its unique features such as biocompatibility, straight peptide chain and the presence of different side chain functionality. These unique features explore peptides in various self-assembly process. In this review, we briefly introduce chemical reaction-mediated peptide self-assembly. Herein, we have emphasised enzymes, native chemical ligation and photochemical reactions in the exploration of peptide self-assembly.