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1.
This study determined the full-length sequence of CYP2E1, one of six cytochrome P450 genes previously examined in camel tissues by western blotting and semi-quantitative PCR. The Camelus dromedarius CYP2E1 has an open reading frame of 1,473 bp, and the cDNA encodes a protein of 490 amino acid residues with a molecular weight of 54.8 kDa. The deduced amino acid sequence showed the highest identity with Bos taurus (88%), Sus scrofa (87%), and Homo sapiens (83%). In a phylogenetic analysis, the C. dromedarius CYP2E1 isoform was located beside cattle and pigs. The deduced amino acid sequence of camel CYP2E1 showed the conserved proline-rich amino terminus and the heme-binding signature localized near the carboxy terminus of the protein.  相似文献   
2.
Primates - Bornean orangutan is a critically endangered non-human primate; however, the threat of extinction is not merely from poaching and habitat loss. Orangutan survival is also threatened by...  相似文献   
3.
Municipal wastewater (WW), if not properly remediated, poses a threat to the environment and human health by carrying significant loads of nutrients and pathogens. These contaminants pollute rivers, lakes, and natural reservoirs where they cause eutrophication and pathogen-mediated diseases. However, the high nutrient content of WW makes it an ideal environment for remediation with microalgae that require high nutrient concentrations for growth and are not susceptible to toxins and pathogens. Given that an appropriate algal strain is used for remediation, the incurred biomass can be refined for the production of biofuel. Four microalgal species (Chlamydomonas reinhardtii, Chlorella sp., Parachlorella kessleri-I, and Nannochloropsis gaditana) were screened for efficient phycoremediation of municipal WW and potential use for biodiesel production. Among the four strains tested, P. kessleri-I showed the highest growth rate and biomass production in 100% WW. It efficiently removed all major nutrients with a removal rate of up to 98% for phosphate after 10 days of growth in 100% municipal WW collected from Delhi. The growth of P. kessleri-I in WW resulted in a 50% increase of biomass and a 115% increase of lipid yield in comparison to growth in control media. The Fatty acid methyl ester (FAME), and fuel properties of lipids isolated from cells grown in WW complied with international standards. The present study provides evidence that the green alga P. kessleri-I effectively remediates municipal WW and can be used to produce biodiesel.  相似文献   
4.
Clinical isolates of Mycobacterium tuberculosis were shown by Southern blotting to contain DNA sequences hybridizing to a probe derived from a Mycobacterium fortuitum plasmid. Two such M. tuberculosis DNA fragments, isolated from a gene library, were used as probes to show restriction fragment length polymorphism in M. tuberculosis strains by detecting a repetitive sequence apparently located at different points on the chromosome. This could indicate the presence of a transposable element in M. tuberculosis which is partly homologous to a region of the M. fortuitum plasmid. The probes described can be used to fingerprint M. tuberculosis isolates, and in addition are capable of distinguishing M. tuberculosis from Mycobacterium bovis and BCG.  相似文献   
5.
Tuberculosis remains a major infectious disease with over 8 million new cases and 2 million deaths annually. Therefore, a vaccine more potent than BCG is desperately needed. In this regard, an approximately 800 bp DNA encoding a mycobacterial synthetic gene designated as VacIII (containing ubiquitin gene UbGR and four immunogenic mycobacterial epitopes or genes of ESAT-6, Phos1, Hsp 16.3, and Mtb8.4) was sub-cloned into a bacterial expression vector of pRSET-B resulting in a 6 x His-VacIII fusion gene construction. This recombinant clone was over expressed in Escherichia coli BL-21 (DE-3). The expressed fusion protein was found almost entirely in the insoluble form (inclusion bodies) in cell lysate. The inclusion bodies were solubilized with 8M urea and the recombinant protein was purified by Ni-NTA column and dialyzed by urea gradient dialysis. This method produced a relatively high yield of recombinant VacIII protein and the cloned VacIII gene offers the potential development of other vaccine formats such as DNA vaccine and recombinant vaccine.  相似文献   
6.
Cotton fiber is the basic raw material used in the textile industry. The fiber yield is severely affected by a number of biotic and abiotic factors, such as insects, viruses, drought and salinity. Drought is a major factor that negatively impacts the yields and quality of cotton fiber. Promoters that respond to stress conditions and up-regulate transgenes are of great significance in crop improvement using genetic engineering approach. Although dehydration-responsive gene promoters, such as RD22 and RD29 from Arabidopsis, have been characterized, not much information is available regarding stress-responsive promoters from Gossypium hirsutum, which accounts for approximately 90 % of cultivated cotton. In this study, we isolated and characterized the promoter of a dehydration-responsive gene (GhRDL1) from G. hirsutum using Agrobacterium-mediated transformation in tobacco and cotton. Transgenic tobacco plants expressing uidA under the GhRDL1 promoter showed GUS activity in the trichomes. Also, GUS expression was observed to some extent in leaf, stem and floral tissues. Similar results were observed when GhRDL1 promoter was tested in transgenic cotton. Most importantly, our study showed that the GhRDL1 promoter is up-regulated in the presence of polyethylene glycol that creates water stress under invitro conditions. Thus, the GhRDL1 promoter may find its usefulness in the development of stress-tolerant cotton and other crop species in the near future.  相似文献   
7.

In this report, a novel D-shaped long-range surface plasmon resonance (LRSPR) fiber base sensor has been introduced. The demonstration of proposed sensor involves two D-shaped silver-coated models to study the sensitivity responses. The entire study with the constructed models is based on a single-mode fiber. The models are multilayered consisting of metal, dielectric, and analyte as separate layers. Silver (Ag) and magnesium fluoride (MgF2) strips are used as metal and dielectric layers respectively. The constituency of analyte as an interface excellently standardized the models for sensitivity detection. In this report, a large range of analyte refractive indices (RI) which varies from 1.33 to 1.38 is appraised for the proposed models to characterize the sensitivity. The entire context is encompassed by the wavelength region from 450 to 850 nm with an interval of 20 nm. Sensitivities in this report are measured based on the analyte position from the core and metal for both models. For each of the two models, the analyte is placed as the top layer. RIs of the applied metal (Ag) are measured using the Drude-Lorentz formula. The simulated sensitivities for model-1 and model-2 vary from 6.3?×?103 nm/RIU to 8.7?×?103 nm/RIU.

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8.

Background  

Several genes have been used as housekeeping genes and choosing an appropriate reference gene is important for accurate quantitative RNA expression in real time RT-PCR technique. The expression levels of reference genes should remain constant between the cells of different tissues and under different experimental conditions. The purpose of this study was to determine the effect of different experimental treatments on the expression of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA so that the reliability of GAPDH as reference gene for quantitative real time RT-PCR in human diploid fibroblasts (HDFs) can be validated. HDFs in 4 different treatment groups viz; young (passage 4), senescent (passage 30), H2O2-induced oxidative stress and γ-tocotrienol (GTT)-treated groups were harvested for total RNA extraction. Total RNA concentration and purity were determined prior to GAPDH mRNA quantification. Standard curve of GAPDH expression in serial diluted total RNA, melting curve analysis and agarose gel electrophoresis were used to determine the reliability of GAPDH as reference gene.  相似文献   
9.
10.
This study evaluated the effect of different salinity levels on the physiology of East Java strain tilapia (Oreochromis niloticus) by measuring the serum osmolalities (SO), ion levels and hematological parameters. Their SOs above the external medium (hyper-osmotic) at 0 and 5 ppt, becoming iso-osmotic at 10 ppt and hypo-osmotic at 15 ppt. The concentrations of serum Na+, K+, Cl? and Ca2+ in fish acclimated in 0 and 5 ppt were not significantly different. The levels of Na+, Cl and Ca2+ in fish exposed to 10 and 15 ppt were higher than those in fish acclimated at 0 and 5 ppt. In contrast, the levels of K+ in fish exposed to 10 and 15 ppt were lower than those in fish exposed to 0 and 5 ppt. The levels of red blood cell, hematocrit and hemoglobin of fish exposed to salinity of 0, 5, 10 and 15 ppt were not significantly different. The levels of white blood cell increased significantly at fish exposed to 10 and 15 ppt. These data provide useful information for future reference and farming practice.  相似文献   
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