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1.
M. Gopalakrishnan P. Sureshkumar J. Thanusu V. Kanagarajan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):347-351
Compound 26 is more potent against Escherichia coli. and 24 is more active against Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, and Shigella flexneri than the standard drug ciprofloxacin. Moreover, of all the compounds tested, 26 is more effective against Aspergillus flavus and Mucor, than the standard drug fluconazole. 相似文献
2.
A bioactive peptide of 8595 Da was purified from the cell free supernatant of Lactococcus garvieae subsp. bovis BSN307T. MALDI MS/MS peptide mapping and the data base search displayed no significant similarity to any reported antimicrobial peptide of LAB. This peptide at a dose concentration of 200 µg ml−1 inhibited the growth of both Gram-positive and Gram-negative bacteria by 58–89% and a dose of 500 µg ml−1 scavenged 50% of DPPH-free radicals generated. Interestingly, cytotoxicity assay demonstrated that 17 µg ml−1 of peptide selectively inhibited 50% proliferation of mammalian cancer cell lines HeLa and MCF-7 whereas normal H9c2 cells remained unaffected. Fluorescent microscopic analysis after DAPI nuclear staining of HeLa cells showed characteristics of apoptosis and activation of caspase-3 was ascertained by caspase-3 fluorescence assay. 相似文献
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4.
《Peptides》2015
It is now well established that peptides that were first identified on the basis of their ability to inhibit growth of bacteria and fungi are multifunctional and so are more informatively described as host-defense peptides. In some cases, their role in protecting the organism against pathogenic microorganisms, although of importance, may be secondary. A previous article in the journal (Peptides 2014; 57:67–77) assessed the potential of peptides present in the skin secretions of frogs for development into anticancer, antiviral, immunomodulatory and antidiabetic drugs. This review aims to extend the scope of this earlier article by focusing upon therapeutic applications of host-defense peptides present in skin secretions and/or skin extracts of species belonging to other vertebrate classes (Agnatha, Elasmobranchii, Teleostei, Reptilia, and Mammalia as represented by the human) that supplement their potential role as anti-infectives for use against multidrug-resistant microorganisms. 相似文献
5.
Nataly Mancette Rijensky Netta R. Blondheim Shraga Eilon Barnea Nir Peled Eli Rosenbaum Aron Popovtzer Solomon M. Stemmer Alejandro Livoff Mark Shlapobersky Neta Moskovits Dafna Perry Eitan Rubin Itzhak Haviv Arie Admon 《Molecular & cellular proteomics : MCP》2020,19(8):1360-1374
Highlights
- •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
- •Using patient derived xenograft (PDX) tumors can overcome this limitation.
- •The large PDX HLA peptidomes expand significantly those of the original biopsies.
- •The HLA peptidomes of the PDX tumors included many tumor antigens.
6.
Lars Terenius Björn Johansson 《Biochemical and biophysical research communications》2010,396(1):140-142
This mini-review outlines the opioid systems and their roles primarily as related to reward and compulsive drug/alcohol intake. The central role is taken by the mu-opioid receptor, target for opiate analgesics and also a central target in compulsive alcohol abuse, alcoholism. The mu-opioid receptor and the cognate opioid neuropeptides from proenkephalin and proopiomelancortin are members of a superfamily of opioid systems, each with unique and still to be defined roles in the central nervous system. 相似文献
7.
The literature pertaining to the use of registered antibacterial agents in Mediterranean finfish farming is reviewed, with
an emphasis on the Greek fish-farming industry. This review provides a scientific resource dedicated to the design of future
antibacterial dosing regimes in Mediterranean fish farming, where insufficient supporting information is currently available.
This paper addresses the paucity in knowledge concerning pharmacokinetics and the efficacy and environmental impact of commonly
used antibacterials needed to direct future research and promote good practices in the euryhaline fish farming industry. Several
registered antibacterials are currently available for combating bacterial infections, including tetracyclines, (fluoro) quinolones,
potentiated sulfa, penicillin and chloramphenicol derivatives. Based on the available data, oxytetracycline (OTC) and quinolone
drugs (oxolinic acid – OA and flumequine – FLU) are the most widely used in Mediterranean aquaculture. As a result these drugs
have received the most extensive studies, whereas, there is considerable paucity of reliable data on pharmacokinetic and the
depletion characteristics of other drugs used, particularly potentiated sulfa, penicillin derivatives and florfenicol. We
find there is incomplete data on drug efficacy and minimum inhibitory concentrations (MIC) for common antibacterials used
against the major bacterial pathogens of Mediterranean fish species. Furthermore, a considerable lack of data on environmental
drug concentrations around Mediterranean fish farms was also identified, highlighting the need for more extensive environmental
studies to monitor contamination in environmental components i.e., water and sediment, and in non-target species (flora and
fauna). Prudent selection and use of antibacterials can encourage lower dosage applications, enhance treatment efficacy, and
help to minimize contamination of the environment. Selection of readily bioavailable drugs which have low environmental persistence,
low aquatic toxicity and high antibacterial efficacy is advised, to reduce potential losses to the environment and associated
toxic effects on target species and the development of bacterial resistance. Lack of present data made it impossible to provide
thorough and accurate guidance on selection and use of antibacterials and approaches for minimizing environmental impacts
for the treatment of major euryhaline aquaculture species. 相似文献
8.
9.
I. N. Suwastika T. Toop H. R. Irving C. A. Gehring 《Plant biology (Stuttgart, Germany)》2000,2(1):1-3
Abstract: An increasing body of evidence suggests that in plants, as in vertebrates, biologically active natriuretic peptide (NP) hormones play an important role in the regulation of the osmotic and ionic balance. The evidence includes isolation and immunoaffinity purification of biologically active natriuretic peptide analogues (irPNP) from ivy that promoted stomatal opening and specifically, rapidly and transiently increased cGMP levels in root conductive tissue. In this study we demonstrate that I125 -rat atrial natriuretic peptide (rANP) binds to plasma membranes from leaf and stem tissue of Tradescantia multiflora and importantly, both unlabelled rANP and irPNP can competitively displace that binding. In addition, tissue section autoradiography reveals specific in situ binding of I125 -rANP to leaf and stem tissue. The findings are consistent with the presence of a biologically active NP system in plants and suggest that NPs signal through a dedicated receptor system. 相似文献
10.
Synthesis and conformational studies of a cecropin-melittin hybrid pentadecapeptide CA(1-7)MEL(2-9), and its three alpha, beta-dehydrophenylalanine (DeltaPhe) containing analogs in water-TFE mixtures are described. DeltaPhe is placed at strategic positions in order to preserve the amphipathicity of the molecule. The wild type CAMEL0 and its three analogs, containing one, two and three DeltaPhe residues namely CAMELDeltaPhe1, CAMELDeltaPhe2 and CAMELDeltaPhe3 respectively were synthesized in solid phase and their conformation determined by CD and NMR. CAMELDeltaPhe2 and CAMELDeltaPhe3 peptides exhibit the presence of 3(10)-helix and beta-turns in the former and only turns in the latter. CAMELDeltaPhe1 peptide was found to have a largely extended conformation. Antibacterial and hemolytic activities of the peptides were also evaluated. CAMELDeltaPhe2 peptide is maximally potent against both Staphylococcus aureus ATCC 259230 and Escherichia coli ATCC 11303. CAMELDeltaPhe1 with a single DeltaPhe at the center shows minimal hemolysis. 相似文献