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991.
A moderately halophilic, mesophilic, Gram-negative, motile, nonsporulating bacterium, designated strain IMPC, was isolated from a table-olive fermentation rich in aromatic compounds, after enrichment on p-coumaric acid under halophilic conditions. Strain IMPC was able to degrade p-coumaric acid. p-hydroxybenzaldehyde and p-hydroxybenzoic acid were detected as breakdown products from p-coumaric acid. Protocatechuic acid was identified as the final aromatic product of p-coumaric acid catabolism before ring fission. Strain IMPC transformed various cinnamic acids with substituent H, OH, CH(3) or OCH(3) in the para- and/or meta-position of the aromatic ring to the corresponding benzoic acids, indicating a specific selection. A beta-oxidation pathway was proposed for these transformations. Phylogenetic analysis of the 16S rRNA gene revealed that this isolate was a member of the genus Halomonas. Strain IMPC was closely related to Halomonas elongata ATCC 33173(T)and Halomonas eurihalina ATCC 49336(T).  相似文献   
992.
BACKGROUND: Carcinosarcoma (sarcomatoid carcinoma) is a rare tumor with a high predilection for the aerodigestive tract. Cytologic diagnosis of metastatic carcinosarcoma has been reported in very few cases. CASE: An 84-year-old woman presented with a 2-cm-diameter, right cervical lymph node that was referred for fine needle aspiration cytology (FNAC). She had received radiotherapy for a palatal squamous cell carcinoma 2 years earlier. The FNAC smears had a sarcomatoid appearance. Repeat fine needle aspiration was performed, with cytologic and immunocytochemical staining. Careful consideration of the cytologic and immunophenotypic features led to an impression of carcinosarcoma. Histologic sections of the palatal biopsy that had been previously diagnosed as squamous cell carcinoma were reviewed, and a final diagnosis of carcinosarcoma was established. CONCLUSION: Metastasis of rare lesions, such as carcinosarcoma may be confusing and difficult to diagnose on FNAC, especially when the cytologic sample shows a predominantly sarcomatoid component. The difficulty is compounded when the sarcomatoid component happens to have been overlooked on the initial histologic assessment. With representative cytologic sampling, immunocytochemical staining and review of the histologic material, the correct diagnosis was achieved in this case.  相似文献   
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Halogenated compounds such as α-halocarboxylix acids (αHAs) are widely liberated into the ecosystem through the prevailing xenobiotic activities that involve the use of herbicides for weed management in the agricultural sector and mass production of various commercial halogenated chemical intermediates. Since such compounds exert stress on the environment owing to their recalcitrance and are not easily degraded, the study aimed to isolate, identify, and characterize dehalogenase-producing bacteria with the purpose of bioremediation. The MX1 bacterium was successfully isolated from seawater samples off the coast of Desaru, Malaysia, using an enrichment technique supplemented with 2,2-dichloropropionic acid (2,2-DCP). Interestingly, the MX1 strain grew best in a 20 mM 2,2-DCP minimal medium as the sole carbon source and illustrated a 44 ± 0.2 h cell-doubling time as well as a 38 μmol Cl?/ml maximum rate of chloride ion release. However, 2,2-DCP–containing medium with concentrations that exceeded 30 mM inhibited the growth of the MX1, possibly attributable to the increased toxicity of the compound on the bacteria. Biochemical examinations and 16S rDNA sequence analysis revealed that the MX1 strain shares high identity to Pseudomonas aeruginosa, and the gene sequence was deposited into GenBank as Pseudomonas aeruginosa MX1 under accession number KP336490. The presence of the putative dehalogenase gene in the MX1 strain was established by polymerase chain reaction (PCR) analysis, which proved the presence of conserved amino acid residues belonging to the Group I dehalogenase. This is the first report detailing a P. aeruginosa strain capable of degrading the recalcitrant 2,2-DCP and its functional amino acid residues.  相似文献   
995.
A spermatic granuloma is a chronic inflammatory reaction produced in response to extravasated sperm within the intertubular connective tissue. The present study investigates the possible toxic effects of water extract of Heliotropium bacciferum on the reproductive system of male albino rats and the associated potential for the development of spermatic granulomas. H. bacciferum is a herbal plant used in traditional medicine and reported to have cytotoxic effects due to pyrrolizidine alkaloids. Histological examinations revealed no changes in the tissues of the testes, although, some changes were detected in the cauda epididymis, the most important of which was the development of small lesions of spermatic granulomas. Clear gaps were observed between the epithelial linings of the epididymal tubules.  相似文献   
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We have previously reported the power of combining a 5'-phosphoramidate ProTide, phosphate pro-drug, motif with a 6-methoxy purine pro-drug entity to generate highly potent anti-HCV agents, leading to agents in clinical trial. We herein extend this work with the disclosure that a variety of alternative 6-substituents are tolerated. Several compounds exceed the potency of the prior 6-methoxy leads, and in almost every case the ProTide is several orders of magnitude more potent than the parent nucleoside. We also demonstrate that these agents act as pro-drugs of 2'-C-methyl guanosine monophosphate. We have also reported the novel use of hepatocyte cell lysate as an ex vivo model for ProTide metabolism.  相似文献   
1000.
Nα‐Boc‐Nim‐(4‐toluenesulfonyl‐l ‐histidylbenzotriazole) enables convenient acylation of N‐, O‐, S‐, and C‐nucleophiles with no detectable racemization. We report efficient syntheses of novel histidine‐containing di‐, tri‐, and tetra‐peptides and models for the preparation of potentially biologically active histidine N‐, O‐, S‐, and C‐conjugates. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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