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991.
Two amides, heitziamide A and heitziamide B and two phenylethanoids, heitziethanoid A and heitziethanoid B together with thirteen known compounds were isolated from F. heitzii (Letouzey). The structures of all compounds were established by spectroscopic analysis.Nine compounds were evaluated for oxidative burst inhibitory activity in a chemoluminescence assay and for cytotoxicity against PC-3 prostate cancer cells.All compounds exhibited a clear suppressive effect on phagocytosis response upon activation with serum opsonized zymosan at the range of IC50 = 2.0–6.5 μM, but no cytotoxic effect was observed (IC50 > 100 μM).  相似文献   
992.
Ectodermal dysplasia syndromes are genetically heterogeneous group of disorders involving one or more of the classical ectodermal appendages (hair, nail, teeth, sweat glands) in association with anomalies of other organs or systems. In the present study a novel form of ectodermal dysplasia syndrome, ectodermal dysplasia cutaneous syndactyly (EDCS), segregating in an autosomal recessive pattern in a Pakistani family was investigated. The clinical features of the affected individuals included large prominent ear pinnae, tooth enamel hypoplasia, hypoplastic nails, bilateral partial cutaneous syndactyly, hypotrichosis, palmoplantar keratoderma and hyperhidrosis. Through genetic linkage study, EDCS syndrome was mapped on human chromosome 7p21.1-p14.3 flanked by markers D7S488 and D7S817. A maximum two-point LOD score of 2.94 (θ = 0.00) was obtained at marker D7S2496 while a maximum multipoint LOD score of 3.07 was obtained with several markers along the disease-interval. This interval spans 19.80-cM, which corresponds to 13.74-Mbp according to the sequence-based physical map (Build 36.1). Sequence analysis of 27 candidate genes, located in the candidate interval, did not reveal any functional sequence variant.  相似文献   
993.
An extracellular xylanase produced under optimal conditions by a thermophilic strain of Bacillus sp. XTR-10 was evaluated for its potential application in biobleaching of wood kraft pulp. Spectrophotometric analysis showed considerable release of lignin derived compounds and chromophoric material by the xylanase treated pulp samples. Xylanase was found to be effective in the liberation of reducing sugars in the pulp filtrates with increment in enzyme dose and reaction time. Eight hours pretreatment with 40 IU of xylanase/g of dry pulp resulted in 16.2% reduction of kappa number with 25.94% ISO increase in brightness as compared to the control. The same treatment slightly lowered the tensile strength and burst index, however. Enzyme pretreatment of the pulp saved 15% active chlorine charges in single step and 18.7% in multiple steps chemical bleaching with attainment of brightness at the level of the control. These results indicate the potential of enzymatic pretreatment of pulp for reduction in environmental discharge of hazardous waste from the pulp and paper industry.  相似文献   
994.
Swine Influenza Virus (H1N1) is a known causative agent of swine flu. Transmission of Swine Influenza Virus form pig to human is not a common event and may not always cause human influenza. The 2009 outbreak by subtype H1N1 in humans is due to transfer of Swine Influenza Virus from pig to human. Thus to analyze the origin of this novel virus we compared two surface proteins (HA and NA) with influenza viruses of swine, avian and humans isolates recovered from 1918 to 2008 outbreaks. Phylogenetic analyses of hemagglutinin gene from 2009 pandemic found to be clustered with swine influenza virus (H1N2) circulated in U.S.A during the 1999-2004 outbreaks. Whereas, neuraminidase gene was clustered with H1N1 strains isolated from Europe and Asia during 1992-2007 outbreaks. This study concludes that the new H1N1 strain appeared in 2009 outbreak with high pathogenicity to human was originated as result of re-assortment (exchange of gene). Moreover, our data also suggest that the virus will remain sensitive to the pre-existing therapeutic strategies.  相似文献   
995.
996.
A rapid, simple in vitro test system for high-throughput screening of peroxisome proliferator-activated receptor (PPAR) γ agonists would be of interest for testing new antidiabetic drugs, alternative medicine, or environmental samples. A yeast two-hybrid assay based on the ligand-dependent recruitment of the coactivator CBP (CREB-binding protein) was constructed. In this system PPARγ was constitutively activated and the signal was not further increased significantly by adding agonists. In yeast we identified oleic acid as a putative endogenous ligand. Furthermore yeasts seem to lack regulatory mechanisms present in mammalian cells. Mammalian systems are an alternative for screening PPARγ agonists.  相似文献   
997.
Plant growth-promoting rhizobacteria with gibberellins (GA)-producing potential were isolated from soil and screened for plant growth promotion. A new strain, Acinetobacter calcoaceticus SE370, produced extracellular GA and also had phosphate solubilising potential. It produced 10 different gibberellins, including the bioactive GA1, GA3 and GA4 which were at, respectively, 0.45, 6.2 and 2.8 ng/100 ml. The isolate solubilised tricalcium phosphate and lowered pH of the medium during the process. Culture filtrates of the organism after growth on broth promoted growth of cucumber, Chinese cabbage and crown daisy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
998.
The microbial biotransformation of Δ9-tetrahydrocannabinol was investigated using a collection of 206 alkane-degrading strains. Fifteen percent of these strains, mainly gram-positive strains from the genera Rhodococcus, Mycobacterium, Gordonia, and Dietzia, yielded more-polar derivatives. Eight derivatives were produced on a mg scale, isolated, and purified, and their chemical structures were elucidated with the use of liquid chromatography-mass spectrometry, 1H-nuclear magnetic resonance (1H-NMR), and two-dimensional NMR (1H-1H correlation spectroscopy and heteronuclear multiple bond coherence). All eight biotransformation products possessed modified alkyl chains, with hydroxy, carboxy, and ester functionalities. In a number of strains, β-oxidation of the initially formed C5 carboxylic acid led to the formation of a carboxylic acid lacking two methylene groups.Δ9-Tetrahydrocannabinol (Δ9-THC) is the decarboxylated product of the corresponding Δ9-THC acid, the major cannabinoid present in the cannabis plant (Cannabis sativa L., Cannabaceae). This compound is officially registered as a drug for the stimulation of appetite and antiemesis in patients under chemotherapy and human immunodeficiency virus therapy regimens. Other biological activities ascribed to this compound include lowering intraocular pressure in glaucoma, acting as an analgesic for muscle relaxation, immunosuppression, sedation, bronchodilation, and neuroprotection (11).Δ9-THC and many of its derivatives are highly lipophilic and poorly water soluble. Calculations of the n-octanol/water partition coefficient (Ko/w) of Δ9-THC at neutral pH vary between 6,000, using the shake flask method (15), and 9.44 × 106, by reverse-phase high-performance liquid chromatography estimation (19). The poor water solubility and high lipophilicity of cannabinoids cause their absorption across the lipid bilayer membranes and fast elimination from blood circulation. In terms of the “Lipinsky rule of 5” (14), the high lipophilicity of cannabinoids hinders the further development of these compounds into large-scale pharmaceutical products.To generate more water-soluble analogues, one can either apply de novo chemical synthesis (as, e.g., in reference 16) or modify naturally occurring cannabinoids, e.g., by introducing hydroxy, carbonyl, or carboxy groups. Chemical hydroxylation of compounds such as cannabinoids is difficult (Δ9-THC is easily converted into Δ8-THC under mild conditions), and therefore microbial biotransformation of cannabinoids is potentially a more fruitful option to achieve this goal.So far, studies on biotransformation of Δ9-THC were mainly focused on fungi, which led to the formation of a number of mono- and dihydroxylated derivatives. Previous reports on the biotransformation of cannabinoids by various microorganisms are summarized in Table Table1.1. The aim of the present study was to test whether bacterial strains are capable of transforming Δ9-THC into new products (with potentially better pharmaceutical characteristics) at a higher yield and specificity than previously found for fungal strains. For this purpose, we have chosen to use a collection of alkane-degrading strains, since it was shown in previous studies (8, 18, 20) that alkane oxygenases often display a broad substrate range. Production of novel cannabinoid derivatives that might have interesting pharmacological activities was another objective of this project.

TABLE 1.

Previous biotransformation experiments conducted using various microorganisms to transform cannabinoids
Cannabinoid(s)aMicroorganism(s) usedNo. of transformed productsReference
Δ9-THCCunninghamella blakesleeana63
Δ8-THCPellicularia filamentosa421
Δ8-THCStreptomyces lavendulae421
Δ6a,10a-THC400 cultures (soil microorganisms)Various1
Nabilone400 cultures (soil microorganisms)Various1
Δ6a,10a-THC358 cultures containing bacteria, actinomycetes, and molds310
Δ9-THC, Δ8-THC, CBD, CBNSyncephalastrum racemosum, Mycobacterium rhodochrousVarious17
Δ9-THCChaetomium globosum37
Δ9-THC51 fungal strains84
NabiloneMicrobesVarious2
Δ9-THCFusarium nivale, Gibberella fujikuroi, and Thamnidium elegans85
Open in a separate windowaCBD, cannabidiol; CBN, cannabinol.  相似文献   
999.
Estimation of Toxic Metals in Scalp Hair Samples of Chronic Kidney Patients   总被引:1,自引:0,他引:1  
The determination of toxic metals (TMs) in the biological samples of human beings is an important clinical screening procedure. The aim of this work is to determine total content of TMs, aluminum (Al), cadmium (Cd), nickel (Ni), and lead (Pb) in scalp hair samples of chronic kidney male patients (CKPs) on maintenance hemodialysis, during the period of 2005–2007. The study included 115 CKPs (all smokers) and 150 controls or referents [82 (nonsmokers) and 68 (smokers)]. Both controls and patients (males) were of the same age group (ranged 25–55 years), socioeconomic status, localities, and dietary habits. The scalp hair samples were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy of the total Al, Cd, Ni, and Pb measurements was tested by simultaneously analyzing certified reference material (human hair NCS ZC81002). No significant differences were observed between the analytical results and the certified values (paired t test at p > 0.05). The levels of TMs in scalp hair samples of patients were found to be higher as compared to control nonsmoker and smokers. Moreover, the study shows that levels of Al, Cd, Ni, and Pb in scalp hair samples may be useful to evaluate the impact of cigarette smoking in kidney failure patients.  相似文献   
1000.
Anwar T  Lal SK  Khan AU 《Bioinformation》2006,1(7):253-256
The importance of influenza viruses as worldwide infectious agents is well recognized. Specific mutations and evolution in influenza viruses is difficult to predict. We studied specific mutations in matrix protein 1 (M1) of H5N1 influenza A virus together with properties associated with it using prediction tools developed in Bioinformatics. Changes in hydrophobicity, polarity and secondary structure at the site of mutation were noticed and documented to gain insight towards its infection.  相似文献   
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