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61.
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Summary This work is an extension of our previous work (Hall et al., 1993) on the synthesis and cytotoxic activity of boronated peptides. The aim of this work was to carry out structural modifications of the amine terminal in compounds1 and2, to increase water solubility, and its effect on the cytotoxicity to tumor cell lines. Surprisingly, only compounds4,7 and8 were more water soluble than the parent compounds. With the exception of compound4, the new derivatives were generally less effective than the parent compounds (1 and2). There was no apparent correlation between structure and activity. Cytotoxic effect was more pronounced in single cell suspended cells. The growth of solid tumor cell lines was not significantly reduced. The most active derivative, (methanamine)dihydro[[[1-(phenylmethyl)-2-methylamino-2-oxoethyl]amino]carboxy]boron (4), inhibited DNA, RNA, and protein synthesis in Tmolt3 cells. Enzymatic activities, e.g., DNA polymerase, m-RNA polymerase, PRPP amidotransferase, carbamyl phosphate synthetase, TMP-kinase, TDP-kinase, dihydrofolate reductase, and ribonucleoside reductase were reduced after 60 min incubation with4. d(TTP) and d(CTP) pool levels were also reduced by 60 min incubation with4.  相似文献   
63.
A new bufonid amphibian, belonging to a new monotypic genus, is described from the Andaman Islands, in the Bay of Bengal, Republic of India, based on unique external morphological and skeletal characters which are compared with those of known Oriental and other relevant bufonid genera. Blythophryne gen. n. is distinguished from other bufonid genera by its small adult size (mean SVL 24.02 mm), the presence of six presacral vertebrae, an absence of coccygeal expansions, presence of an elongated pair of parotoid glands, expanded discs at digit tips and phytotelmonous tadpoles that lack oral denticles. The taxonomic and phylogenetic position of the new taxon (that we named as Blythophryne beryet gen. et sp. n.) was ascertained by comparing its 12S and 16S partial genes with those of Oriental and other relevant bufonid lineages. Resulting molecular phylogeny supports the erection of a novel monotypic genus for this lineage from the Andaman Islands of India.  相似文献   
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Dry anaerobic bio-conversion (D-AnBioC) of high-solid organic substrates (OS) is considered as a sustainable option for waste management practices in different parts of the world. The basic technology is well implemented, but the improvements are still under way in terms of optimization and pre- and post-treatments of the feed and end-products, respectively. The purpose of this review is mainly to: (1) provide existing knowledge and research advances in D-AnBioC systems to treat high-solid OS; (2) identify major issues involved in bioreactor designing; (3) present factors influencing the bio-conversion efficiency; (4) discuss the microbiology of system operation; (5) provide examples of existing commercial-scale plants; (6) discuss energy and economics requirements. From the detailed literature review, it is clear that the characteristics of OS are the major factors governing the overall process and economics. It shows that not all OS are profitably recycled using D-AnBioC systems. Compared to single-stage continuous systems, batch systems under a multi-stage configuration appears to be economically feasible, however, it must be noted that the available data sets are still inconclusive. Also, limited information is available on green house gas mitigation and restoration of nutrients from the digested residue during post-treatment schemes. A summary at the end presents important research gaps of D-AnBioC system to direct future research.  相似文献   
66.
Microbial communities ultimately control the fate of petroleum hydrocarbons (PHCs) that enter the natural environment, but the interactions of microbes with PHCs and the environment are highly complex and poorly understood. Genome-resolved metagenomics can help unravel these complex interactions. However, the lack of a comprehensive database that integrates existing genomic/metagenomic data from oil environments with physicochemical parameters known to regulate the fate of PHCs currently limits data analysis and interpretations. Here, we curated a comprehensive, searchable database that documents microbial populations in natural oil ecosystems and oil spills, along with available underlying physicochemical data, geocoded via geographic information system to reveal their geographic distribution patterns. Analysis of the ~2000 metagenome-assembled genomes (MAGs) available in the database revealed strong ecological niche specialization within habitats. Over 95% of the recovered MAGs represented novel taxa underscoring the limited representation of cultured organisms from oil-contaminated and oil reservoir ecosystems. The majority of MAGs linked to oil-contaminated ecosystems were detectable in non-oiled samples from the Gulf of Mexico but not in comparable samples from elsewhere, indicating that the Gulf is primed for oil biodegradation. The repository should facilitate future work toward a predictive understanding of the microbial taxa and their activities that control the fate of oil spills.  相似文献   
67.
A newly synthesized 1, 4‐bis ((4‐((4‐heptylpiperazin‐1‐yl) methyl)‐1H‐1, 2, 3‐triazol‐1‐yl) methyl) benzene from the family of piperazine derivative has good anticancer activity, antibacterial and low toxic nature; its binding characteristics are therefore of huge interest for understanding pharmacokinetic mechanism of the drug. The binding of piperazine derivative to bovine serum albumin (BSA) was investigated using fluorescence spectroscopy. The molecular distance r between the donor (BSA) and acceptor (piperazine derivative) was estimated according to Forster's theory of nonradiative energy transfer. The physicochemical properties of piperazine derivative, which induced structural changes in BSA, have been studied by circular dichroism and those chemical environmental changes were probed using Raman spectroscopic analysis. Further, the binding dynamics was expounded by synchronous fluorescence spectroscopy and molecular modeling studies explored the hydrophobic interaction and hydrogen bonding results, which stabilize the interaction.  相似文献   
68.
Preanalytical variables play a key role in discovery of biomarkers. Although the effect of several preanalytical variables on the mass spectral profiles has been studied extensively, little is known about long-term storage of serum samples. This is important because samples used in case-control or epidemiological studies are usually stored for a long time before analysis. Here we evaluated long-term storage effects on mass spectral peak patterns of serum peptides extracted using weak cation exchange magnetic beads. For this, 20 serum samples stored at −80 °C were divided equally into two groups based on their storage time. We found that intensities of 26 mass spectral peaks significantly varied between these two groups. Intensities of these peaks significantly correlated with storage time. Genetic algorithm-based models generated using these 26 peaks could classify 63 additional samples into these two groups with 100% and 96% accuracy, respectively. We also show that storing samples for 10 months at −80 and −20 °C results in the appearance/disappearance or intensity variation of peaks, some of which were previously reported as disease biomarkers.  相似文献   
69.
Diethylnitrosamine (DEN), found in many commonly consumed foods, is widely reported to induce cancer in animals and humans. The aim of the present study was to investigate the hepatoprotective and antioxidant activities of the leaf extract of the medicinal plant Cassia fistula Linn. against diethylnitrosamine induced liver injury in ethanol pretreated rats. Albino Wistar rats, pretreated with ethanol for 15 days, were administered a single dose of DEN. Thirty days after DEN administration, hepatotocellular damage was observed histologically, along with elevated levels of serum AST, ALT, ALP, LDH, γ-GT and bilirubin and a simultaneous fall in the levels of the marker enzymes in the liver tissue. Liver oxidative stress was confirmed by elevated levels of lipid peroxidation (LPO) and a decrease in enzymic and non-enzymic antioxidants activities. Oral administration of the ethanolic leaf extract (ELE) of Cassia fistula for 30 days to ethanol + DEN treated rats significantly improved the above alterations in the markers of hepatotoxicity and oxidative stress, resulting in the reversal of most of the parameters studied and were comparable to the standard hepatoprotective drug silymarin.  相似文献   
70.
Different leaf extracts of Garlic creeper (Adenocalymma alliaceum Miers.) using water and solvents were prepared and they were screened for their antifungal activity against Colletotricum gloeosporioides Penz. and Botryodiplodia theobromae Pat. causal agents of mango post harvest diseases viz., anthracnose and stem end rot respectively. Among the extracts tested, chloroform extract was found to be highly effective in inhibiting the spore germination of C. gloeosporioides by 84.62% and B. theobromae by 84.50% followed by methanol extract. The extracts were also inhibitory to the mycelium. Ammonium sulphate precipitation and SDS–PAGE analysis of the extract indicated the presence of a major protein with a molecular weight at 65 kDa. Two blue spots at Rf 0.96 and 0.80 was also observed in TLC analysis and the presence of tannic acid, resorcinol was evident from HPLC analysis. Treatment of fruits with leaf extract of A. alliaceum increased the activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and sugars with significant reduction in starch, phenolics, protein and ascorbic acid. The extract was partially purified and formulated as ADENOCAL 60 EC for the management of post harvest diseases of mango fruits.  相似文献   
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