889 resultados para Barker frog
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Previous in vivo study demonstrated that beta gamma-CAT, a newly identified non-lens beta gamma-crystallin and trefoil factor complex from frog Bombina maxima skin secretions, possessed potent lethal toxicity on mammals resulted from hypotension and cardi
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The crab-eating frog, Rana cancrivora, is one of only a handful of amphibians worldwide that tolerates saline waters. It typically inhabits brackish water of mangrove forests of Southeast Asia. A large amount of antimicrobial peptides belonging to different families have been identified from skins of amphibians inhabiting freshwater. No antimicrobial peptide from sea amphibians has been reported. In this paper, we firstly reported the antimicrobial peptide and its cDNA cloning from skin secretions of the crab-eating frog R. cancrivora. The antimicrobial peptide was named cancrin with an amino acid sequence of GSAQPYKQLHKVVNWDPYG. By BLAST search, cancrin had no significant similarity to any known peptides. The cDNA encoding cancrin was cloned from the cDNA library of the skin of R. cancrivora. The cancrin precursor is composed of 68 amino acid residues including a signal peptide, acidic spacer peptide, which are similar to other antimicrobial peptide precursors from Ranid amphibians and mature cancrin. The overall structure is similar to other amphibian antimicrobial peptide precursors although mature cancrin is different from known peptides. The current results reported a new family of amphibian antimicrobial peptide and the first antimicrobial peptide from sea amphibian. (c) 2007 Elsevier Ltd. All rights reserved.
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While investigating the innate defense of brackish water-living amphibian and its comparison with freshwater-living amphibians, two novel 12-residue antimicrobial peptides were purified from the skin secretions of the crab-eating frog, Fejervarya cancrivo
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More than ten bradykinin-related peptides and their cDNAs; have been identified from amphibians, but their genes are unknown. In present study, four cDNAs encoding one, two, four and six copies of bradykinin-related peptides were cloned from the frog (Odorrana grahami) skin cDNA library, respectively. Three bradykinin-related peptides (bradykinin, Thr6-bradykinin, Leu5Thr6-bradykinin) were deduced from these four cDNA sequences. Based on the cDNA sequence, the gene sequence encoding an amphibian bradykinin-related peptide from O. grahami was determined. It is composed of 7481 base pairs including two exons and two introns. The first exon codes signal peptide and the second exon codes acidic spacer peptide and Thr6-bradykinin. The promoter region of the bradykinin gene contains several putative recognition sites for nuclear factors, such as SRY, GATA-1, LYF-1, DeltaE, CDXA, NKX-2.5, MIF1 and S8. The current work may facilitate to understand the regulation and possible functions of amphibian skin bradykinin-related peptides. (C) 2009 Elsevier Masson SAS. All rights reserved.
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The effect of AC and DC electric stimulations on the heart-rate and the entire body of Heteropneustis fossillis, Tilapia mossambica and Macrobrachium rosenbergii were studied and presented in kymograph tracings. The reaction of spinal cord in Puntius ticto, Heteropneustis fossilis and Tilapia mossambica to D. C. field was observed to find out its role in electric shocks. A test-check of the electrical resistance of a few species was also conducted. The effect of D. C. and A.C. on the body muscle was found to be the same as that in the case of frog. Different degrees of cardiac slowing were observed in AC and DC. Unbalanced galvanotropic movements were also noticed in spinal fishes.
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The isolation of a new serotype, S. larochelle (6, 7: eh:1, 2), is reported in this communication. This serotype has not so far been reported from any source in this country. The serotype was isolated on November 27th, 1979 at Bombay from a market sample of frozen frog legs intended for domestic consumption.
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India's export earnings from fishery products have touched an all-time record of Rs. 33.07 crores in 1969. The most important items which have contributed to this are processed prawn products, frozen lobster tails and frozen frog legs. Even though frogs are not of marine origin, they are processed and exported along with marine products so that for all practical purposes they are reckoned as seafood. Naturally, it is sure to be of absorbing interest to the processors and technological research workers as well as to the general public to know how many varieties/species of these occur in our country and also the localities where they are available. The following is an exhaustive list of the different species of prawns, lobsters and frogs that are found in our country, together with vernacular names wherever available, parts of India where they occur and the largest size (length) to which they grow. The figures in brackets on the left side show the progressive total. The different genera have been arranged in the order of their commercial importance and not according to any scientific principles.
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Changes in physical, organoleptic and biochemical characteristics of phosphate treated prawns and frog legs during storage have been studied in detail by Mathen and Pillai, (1970). Adoption of the recommended method by the industry in the freezing of prawns made it necessary to assess the influence of such treatment on the bacterial quality. This aspect assumes more importance in view of the proposed compulsory bacterial standards for raw frozen prawns. This note gives an account of the results on the influence of phosphate treatment on bacterial quality of raw frozen shrimp meat.
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Based on partial sequences of the 12S and 16S ribosomal RNA genes, we estimated phylogenetic relationships among brown frogs of the Rana temporaria group from China. From the phylogenetic trees obtained, we propose to include Rana zhengi in the brown frog
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The human genome project has been recently complemented by whole-genome assessment sequence of 32 mammals and 24 nonmammalian vertebrate species suitable for comparative genomic analyses. Here we anticipate a precipitous drop in costs and increase in sequ
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Eastern and western populations of the ranid frog Odorrano chapaensis from Vietnam and China are readily differentiated by morphology and mtDNA, and weakly differentiated by morphometrics. The western population contains the type localities of O. chopoens
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在西藏墨脱采集到1种与Odorrana graminea、O.chloronota和O.livida体背绿色和指端膨大具沟的湍流蛙类相近的物种,经鉴定为新种,命名为墨脱臭蛙Odorrana zhaoi.新种具有以下主要特征:上唇缘具有金黄色条纹;鼓膜圆形,显著,TD:ED为0.56;背侧褶弱,背部皮肤除后部有小疣粒外光滑,体侧有疣粒和小刺;4肢背面有横斑纹;无外蹠突;雄性具1对外声囊和咽胸部椭圆形小刺团,无肱腺.
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The brushless doubly fed machine (BDFM) is a robust alternative to the doubly fed induction generator (DFIG) which is widely used in wind turbines but suffers from failures associated with its brushes and sliprings. The rotor plays an important part in a BDFM, coupling the two stator fields. To date, the nested loop has been almost exclusively used in modern BDFMs, but this approach is not ideally suited to large machines in which a form wound rotor is likely to be preferable from a manufacturing point of view. This paper gives a comparative study of two rotor windings. The performance of the rotors has been predicted from theory for a frame size 160 BDFM. Actual rotors have been built, using identical rotor laminations, and tested, giving results which accord well with predictions. The results give insight into the design issues of rotors both from electrical and manufacturing viewpoints. ©2010 IEEE.
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Self-assembled structures capable of mediating electron transfer are an attractive scientific and technological goal. Therefore, systematic variants of SH3-Cytochrome b(562) fusion proteins were designed to make amyloid fibers displaying heme-b(562) electron transfer complexes. TEM and AFM data show that fiber morphology responds systematically to placement of b(562) within the fusion proteins. UV-vis spectroscopy shows that, for the fusion proteins under test, only half the fiber-borne b(562) binds heme with high affinity. Cofactor binding also improves the AFM imaging properties and changes the fiber morphology through changes in cytochrome conformation. Systematic observations and measurements of fiber geometry suggest that longitudinal registry of subfilaments within the fiber, mediated by the interaction and conformation of the displayed proteins and their interaction with surfaces, gives rise to the observed morphologies, including defects and kinks. Of most interest is the role of small molecule modulation of fiber structure and mechanical stability. A minimum complexity model is proposed to capture and explain the fiber morphology in the light of these results. Understanding the complex interplay between these factors will enable a fiber design that supports longitudinal electron transfer.
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Amyloid fibres displaying cytochrome b562 were probed using scanning tunnelling microscopy (STM) in vacuo. The cytochromes are electron transfer proteins containing a haem cofactor and could, in principle, mediate electron transfer between the tip and the gold substrate. If the core fibres were insulating and electron transfer within the 3D haem network was detected, then the electron transport properties of the fibre could be controlled by genetic engineering. Three kinds of STM images were obtained. At a low bias (<1.5 V) the fibres appeared as regions of low conductivity with no evidence of cytochrome mediated electron transfer. At a high bias, stable peaks in tunnelling current were observed for all three fibre species containing haem and one species of fibre that did not contain haem. In images of this kind, some of the current peaks were collinear and spaced around 10 nm apart over ranges longer than 100 nm, but background monomers complicate interpretation. Images of the third kind were rare (1 in 150 fibres); in these, fully conducting structures with the approximate dimensions of fibres were observed, suggesting the possibility of an intermittent conduction mechanism, for which a precedent exists in DNA. To test the conductivity, some fibres were immobilized with sputtered gold, and no evidence of conduction between the grains of gold was seen. In control experiments, a variation of monomeric cytochrome b562 was not detected by STM, which was attributed to low adhesion, whereas a monomeric multi-haem protein, GSU1996, was readily imaged. We conclude that the fibre superstructure may be intermittently conducting, that the cytochromes have been seen within the fibres and that they are too far apart for detectable current flow between sites to occur. We predict that GSU1996, being 10 nm long, is more likely to mediate successful electron transfer along the fibre as well as being more readily detectable when displayed from amyloid.