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61.
Bacillus mucilaginosus has already been proved to be capable of degrading silicate minerals, but it is not very clear about the molecular mechanisms of bacterial mineral weathering. To understand the relationship between bacterial weathering of minerals and bacterial secreted proteins, B. mucilaginosus was chosen to study the expression of its extracellular proteins in the process of weathering potassium minerals. This article reveals that certain secreted proteins, related to weathering of potassium minerals, can be induced under conditions such as bacterial nutritional deficiency and the existence of K-bearing rock powders. This suggests direct evidence of the metabolic changes of extracellular enzymes in bacteria during the process of weathering of potassium minerals. It was speculated that these secreted proteins, together with extracellular polymers like polysaccharides, may accelerate the weathering of potassium minerals, resulting in the release of K+ needed for the bacterial growth. 相似文献
62.
Thioacetamide induced liver damage in zebrafish embryo as a disease model for steatohepatitis 总被引:2,自引:0,他引:2
Amali AA Rekha RD Lin CJ Wang WL Gong HY Her GM Wu JL 《Journal of biomedical science》2006,13(2):225-232
Summary Steatohepatitis has recently been increasing as a cofactor influencing the progression of fibrosis, cirrhosis, adenoma and
carcinoma in liver; however, the mechanisms by which it contributes to liver injury remain uncertain. We induced steatohepatitis
in zebrafish embryos using thioacetamide (TAA). TUNEL assay revealed significant increasing of apoptosis in liver after 5 days
post fertilization and the increasing of apoptosis was observed to be associated with the up-regulation of apoptotic genes
such as, bad, bax, P-38a, caspase-3 and 8, and JNK-1. Histological sections by oil red O stain showed the accumulation of
fatty droplets which causes the pushing of the nucleus towards one side. Up-regulation of steatosis markers such as, ACC,
adiponectin, PTL, CEBP- and , SREBP-1 was also observed. Furthermore, the elevation of glutathione peroxidase in TAA treated embryos indicated that TAA
induces lipid peroxidation which leads to causes liver damage. Zebrafish has already been considered as a good human disease
model and in this context; TAA-treated zebrafish may serve as a good animal model to study the molecular pathogenesis of steatohepatitis.
Moreover, non-availability of specific drugs to prevent steatohepatitis, this animal model may serve as a powerful preclinical
platform to study the therapeutic strategies and for evaluating chemoprevention strategies for this disease. 相似文献
63.
64.
Global warming alerts and threats are on the rise due to the utilization of fossil fuels. Alternative fuel sources like bio-ethanol and biodiesel are being produced to combat against these threats. Bio-ethanol can be produced from a range of substrate. The present study is aimed at the Production of bioethanol from pretreated agricultural substrate using enzymatic hydrolysis and simultaneous saccharification with the addition of purified fungal enzyme. Most cellulosic biomass is not fermentable without appropriate pretreatment methods and so dilute sulfuric acid pretreatment was applied to make the cellulose contained in the waste susceptible to endoglucanase enzyme. A range of acid pretreatment of wheat bran was made in which the sample that was pretreated with 1% dilute sulfuric acid gave maximum yield of ethanol in both methods such as 5.83 g L(-1) and 5.27 g L(-1), respectively. Ethanol produced from renewable and cheap agricultural products (wheat bran) provides reduction in green house gas emission, carbon monoxide, sulfur, and helps to eliminate smog from the environment. 相似文献
65.
Kumar KS Rambabu D Sandra S Kapavarapu R Krishna GR Basaveswara Rao MV Chatti K Reddy CM Misra P Pal M 《Bioorganic & medicinal chemistry》2012,20(5):1711-1722
A direct and single-step method has been developed for the synthesis of mono and 2,3-disubstituted quinoxalines by using a AlCl(3) induced (hetero)arylation of 2,3-dichloroquinoxaline. Both symmetrical and unsymmetrical 2,3-disubstituted quinoxalines can be prepared conveniently by using this method under appropriate reaction conditions. The reaction proceeds via C-C bond formation and can be utilized for the preparation of a variety of quinoxaline derivatives from readily available starting materials and reagents. The molecular structure of a representative compound was confirmed by single crystal X-ray diffraction study. Some of the compounds synthesized were tested for chorismate mutase inhibitory properties in vitro and one compound showed promising activity representing one of the few examples of chorismate mutase inhibition by a heteroarene based small molecule. 相似文献
66.
Kumar KS Kiran Kumar S Yogi Sreenivas B Gorja DR Kapavarapu R Rambabu D Rama Krishna G Reddy CM Basaveswara Rao MV Parsa KV Pal M 《Bioorganic & medicinal chemistry》2012,20(7):2199-2207
A number of 2-(1H-indol-3-yl)quinoline-3-carbonitrile derivatives were synthesized via AlCl(3)-mediated C-C bond forming reaction between 2-chloroquinoline-3-carbonitrile and various indoles. The methodology does not require any N-protection of the indoles employed and provided the corresponding products in good yields. The molecular structure of a representative compound was established unambiguously by single crystal X-ray diffraction and structural elaboration of a compound synthesized has been demonstrated. Many of these compounds synthesized showed PDE4 inhibitory properties in vitro. A brief structure-activity relationship studies within the series along with docking results of a representative compound (EC(50) ~0.89 μM) is presented. 相似文献
67.
Srinivasan M Aalinkeel R Song F Mitrani P Pandya JD Strutt B Hill DJ Patel MS 《American journal of physiology. Endocrinology and metabolism》2006,290(1):E129-E134
We have previously shown that artificial rearing of newborn female rat pups on a high-carbohydrate (HC) milk formula resulted in chronic hyperinsulinemia and adult-onset obesity (HC phenotype) and that the maternal HC phenotype was transmitted to their progeny (2-HC rats) because of fetal development in the HC female rat. The aims of this study were to investigate 1) the fetal adaptations that predisposed the progeny for the expression of the HC phenotype in adulthood and 2) whether the transfer of the HC phenotype to the progeny could be reversed by maternal food restriction. Fetal parameters such as plasma insulin and glucose levels, mRNA level of preproinsulin gene, pancreatic insulin content, and islet insulin secretory response in vitro were determined. On gestational day 21, 2-HC fetuses were hyperinsulinemic, had increased insulin content and mRNA level of the preproinsulin gene in their pancreata and demonstrated an altered glucose-stimulated insulin secretory response by isolated islets. Modification of the intrauterine environment in HC female rats was achieved by pair feeding them to the amount of diet consumed by age-matched control rats from the time of their weaning. This mild dietary restriction reversed their HC phenotype and also prevented the development of the HC phenotype in their progeny. These findings show that mal-programming of the progeny of the hyperinsulinemic-obese HC female for the expression of the HC phenotype is initiated in utero and that normalization of the maternal environment in HC female rats by mild food restriction resulted in the normal phenotype in their progeny. 相似文献
68.
Creatine (Cr), an ergogenic nutritional supplement is demonstrated to possess bioenergetic, antiexcitotoxic and antioxidant
properties. This study investigated the neuroprotective effects of Cr against rotenone induced oxidative stress, mortality
and neurotoxicty in Drosophila melanogaster. We found significant diminution in the endogenous levels of oxidative markers in whole body homogenates of flies exposed
to Cr (2–10 mM). Cr supplementation resulted in reduced mortality in flies exposed to rotenone (500 μM) and better performance
in a negative geotaxis assay. Further Cr (10 mM) markedly offset rotenone induced mitochondrial oxidative stress, completely
restored the GSH levels, nitric oxide levels, activity of Mn-SOD and dopamine depletion. In an oxidative stress bioassay,
flies given Cr prophylaxis exhibited marked resistance to paraquat exposure. These data allow us to hypothesize that the neuroprotective
action of Cr in Drosophila may be related to its direct antioxidant activity and ability to abrogate rotenone induced mitochondrial oxidative stress. 相似文献
69.
Ashley R. Winslow Chien-Wen Chen Silvia Corrochano Abraham Acevedo-Arozena David E. Gordon Andrew A. Peden Maike Lichtenberg Fiona M. Menzies Brinda Ravikumar Sara Imarisio Steve Brown Cahir J. O��Kane David C. Rubinsztein 《The Journal of cell biology》2010,190(6):1023-1037
Parkinson’s disease (PD) is characterized pathologically by intraneuronal inclusions called Lewy bodies, largely comprised of α-synuclein. Multiplication of the α-synuclein gene locus increases α-synuclein expression and causes PD. Thus, overexpression of wild-type α-synuclein is toxic. In this study, we demonstrate that α-synuclein overexpression impairs macroautophagy in mammalian cells and in transgenic mice. Our data show that α-synuclein compromises autophagy via Rab1a inhibition and Rab1a overexpression rescues the autophagy defect caused by α-synuclein. Inhibition of autophagy by α-synuclein overexpression or Rab1a knockdown causes mislocalization of the autophagy protein, Atg9, and decreases omegasome formation. Rab1a, α-synuclein, and Atg9 all regulate formation of the omegasome, which marks autophagosome precursors. 相似文献
70.
There is a distinct need for antimicrobial compounds that can act at surfaces without leaching into the environment. Such materials should be easy to synthesize, be easy to apply to surfaces, and display reasonable levels of antimicrobial and antifungal activity. Here we describe such a surface-active compound and demonstrate its ability to inhibit the growth of the filamentous fungus Aspergillus niger. We have synthesized a series of polyquaternary ammonium compounds by atom transfer radical polymerization. Two members of this series were tested for their ability to inhibit the growth of A. niger. The compounds were dried onto surfaces, and the treated surfaces were then used as growth chambers for A. niger. A water soluble polyquaternary amine compound was shown to effectively kill A. niger in solution in a dose-dependent manner. Conversely, a water insoluble polyquaternary amine compound was shown to kill only the fungi in direct contact with the material on the surface. These results have important implications for the development of effective, environmentally benign, surface-active anti-fungal compounds. 相似文献