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71.
Molecular Biology Reports - Thelandros is a genus of oxyurid nematodes which parasitize both omnivorous and herbivorous hosts. Thelandros chalcidiae sp. nov. is a new taxa described from the large...  相似文献   
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Gastrointestinal toxicity is one of the most serious side effects in the methotrexate (MTX) treatment. This study was designed to investigate whether ellagic acid (EA) and/or pumpkin seed oil (PSO) had a protective effect on MTX-induced small intestine damage. Forty albino rats were randomized into five groups of 8 rats each. Group I served as a normal control group. In Group II, MTX was administered as a single dose (20 mg/kg) intraperitoneally. Groups III, IV and V were pre-treated respectively with either PSO (40 mg/kg), EA (10 mg/kg) or 0.2% DMSO (vehicle control) orally every day by gavage for 5 days and then they received MTX. All animals were sacrificed 5 days after the intraperitoneal injection of MTX for histopathological examination, estimation of serum prostaglandin E2 (PGE2) level, assay of tissue malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NO) levels and myloperoxidase (MPO), xanthine oxidase (XO) and adenosine deaminase (AD) activities. Administration of EA and/or PSO decreased the intestinal damage, PGE2, MDA and NO levels and MPO, XO and AD activities and increased GSH level. These results suggest that EA and PSO protect the small intestine of rats from MTX-induced damage through their antioxidant and anti-inflammatory effects and thus have potential as a promising drug in the prevention of undesired side effects of MTX.  相似文献   
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The genome of the anaerobic halophilic alkalithermophile Natranaerobius thermophilus consists of one 3,165,557-bp chromosome and two plasmids (17,207 bp and 8,689 bp). The present study is the first to report the completely sequenced genome of an anaerobic polyextremophile and genes associated with roles in regulation of intracellular osmotic pressure, pH homeostasis, and growth at elevated temperatures.  相似文献   
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The farnesoid X receptor (FXR) is involved in glucose and lipid metabolism regulation, which makes it an attractive target for the metabolic syndrome, dyslipidemia, atherosclerosis, and type 2 diabetes. In order to find novel FXR agonists, a structure-based pharmacophore model collection was developed and theoretically evaluated against virtual databases including the ChEMBL database. The most suitable models were used to screen the National Cancer Institute (NCI) database. Biological evaluation of virtual hits led to the discovery of a novel FXR agonist with a piperazine scaffold (compound 19) that shows comparable activity as the endogenous FXR agonist chenodeoxycholic acid (CDCA, compound 2).  相似文献   
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We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured heterotrophic Planctomycetes were identified, the majority of the sequences belonged to several globally distributed, as-yet-uncultured Planctomycetes lineages. Using complex organic media (aqueous extracts of the spring sediments and rumen fluid), we isolated two novel strains that belonged to the Pirellula-Rhodopirellula-Blastopirellula clade within the Planctomycetes. The two strains had identical 16S rRNA gene sequences, and their closest relatives were isolates from Kiel Fjord (Germany), Keauhou Beach (HI), a marine aquarium, and tissues of marine organisms (Aplysina sp. sponges and postlarvae of the giant tiger prawn Penaeus monodon). The closest recognized cultured relative of strain Zi62 was Blastopirellula marina (93.9% sequence similarity). Detailed characterization of strain Zi62 revealed its ability to reduce elemental sulfur to sulfide under anaerobic conditions, as well as its ability to produce acids from sugars; both characteristics may potentially allow strain Zi62 to survive and grow in the anaerobic, sulfide- and sulfur-rich environment at the spring source. Overall, this work indicates that anaerobic metabolic abilities are widely distributed among all major Planctomycetes lineages and suggests carbohydrate fermentation and sulfur reduction as possible mechanisms employed by heterotrophic Planctomycetes for growth and survival under anaerobic conditions.  相似文献   
76.
The aim of the present study was to utilize chitosan (CS) nanoparticles for the intracellular delivery of the poorly cell-penetrating antibiotic, ceftriaxone sodium (CTX). In vitro characterization of (CTX-CS) nanoparticles was conducted leading to an optimized formula that was assessed for its biocompatibility to blood (hemolysis test) and cells (MTT assay). Progressively, confocal laser scanning microscopy (CLSM), cellular uptake (microfluorimetry), and antibacterial activity of the nanoparticles were investigated in two cell lines: Caco-2 and macrophages J774.2 pre-infected with Salmonella typhimurium. Results showed that the optimized formula had size 210 nm, positive zeta potential (+30 mV) and appreciable entrapment efficiency for CTX (45%) and included a biphasic release pattern. The nanoparticles were biocompatible and were internalized by cells as verified by CLSM whereas microfluorimetry indicated substantial cellular uptake. Moreover, the CTX–chitosan nanoparticles showed a significant reduction in the count of intracellular S. typhimurium in Caco-2 and macrophages J774.2. This reduction was significantly higher than that obtained in case of placebo nanoparticles, CTX, and CTX–chitosan solutions and might be attributed to enhanced endocytic uptake of the nanoaprticles and antibacterial effect of the chitosan polymer. In conclusion, the results provide evidence for the potential use of chitosan nanoparticles to enhance the intracellular delivery and antibacterial effect of CTX in enterocytes and macrophages.Key words: ceftriaxone sodium, chitosan nanoparticles, enterocytes, intracellular delivery, macrophages  相似文献   
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Hepatocellular carcinoma (HCC) is the most common form of malignancy in the liver. Autophagy was found to have a significant effect in controlling HCC. Anthocyanins, which are naturally occurring pigments in a variety of fruits and vegetables, have been thoroughly documented to be involved in a variety of bioactive activities and are widely employed for their antioxidant capabilities. Cyanidin-3-glucoside (C3G) extracted from Morus alba L. has promising antioxidant and anti-tumour activities. The current study aims to examine the protective action of C3G against hepatocellular carcinoma through the investigation of the autophagy protein ATG16L1 expression along with its related RNA molecules (hsa_circ_0001345 and miRNA106b) in Wistar rats. In vivo precancerous lesions (PCL) were induced using diethylnitrosamine (DEN) and acetamidofluorene (2-AAF). Rats were treated with C3G (10, 15, and 20 mg/kg; 4 times weekly) for 112 days (16 weeks). Liver function tests, alfa fetoprotein, ATG16L1 expression, hsa_circ_0001345, and miRNA106b differential expression were examined. Liver sections were examined by histological and immunohistochemical approaches. The current study’s findings indicated that C3G administration protects against the negative effects of DEN-2-AAF on liver functions and liver histopathological sections, which nominated C3G as a potential prophylactic agent against HCC.  相似文献   
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