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1.
Beta-urogastrone also known as human epidermal growth factor is a key member of epidermal growth factor family having role in cell proliferation and differentiation in vivo as well as in vitro. Human epidermal growth factor gene has been isolated from different tissues but the method of isolation is technically difficult and complicated as it deals with biopsies. Here we isolated mature partial human epidermal growth factor gene from Huh-7 cell line, amplified and abridged toward mature coding region with three steps PCR, sequenced for homology with wild type human epidermal growth factor gene, inbuilt with sites of interest and cloned in Pichia pastoris for expression study. Isolated mature human epidermal growth factor gene from Huh-7 cell line showed 100 % sequence homology to wild type human epidermal growth factor gene and gives the native expression for human epidermal growth factor peptide. In this study we report that Huh-7 cell line is an easy source for the particular gene of human epidermal growth factor isolation and we are also suggesting P. pastoris is an expression system to produce recombinant human epidermal growth factor of the therapeutic importance resembling to the natural human system.  相似文献   
2.
RNA interference (RNAi) is a powerful tool for functional gene analysis which has been successfully used to downregulate the expression levels of target genes. The goal of this research was to provide a highly robust and concise methodology for in-vitro screening of efficient siRNAs from a bulk to be used as a tool to protect potato plants against PVY invasion. In our study, a 480bp fragment of the capsid protein gene of potato virus Y (CP-PVY) was used as a target to downregulate PVY mRNA expression in-vitro, as the CP gene interferes with viral uncoating, translation and replication. A total of six siRNAs were designed and screened through transient transfection assay and knockdown in expression of CP-PVY mRNA was calculated in CHO-k cells. CP-PVY mRNA knockdown efficiency was analyzed by RT-PCR and real-time PCR of CHO-k cells co-transfected with a CP gene construct and siRNAs. Six biological replicates were performed in this study. In our findings, one CP gene specific siRNA out of a total of six was found to be the most effective for knockdown of CP-PVY mRNA in transfected CHO-k cells by up to 80%–90%.  相似文献   
3.
Proboscipedia (PB) is a HOX protein required for adult maxillary palp and proboscis formation. To identify domains of PB important for function, 21 pb point mutant alleles were sequenced. Twelve pb alleles had DNA sequence changes that encode an altered PB protein product. The DNA sequence changes of these 12 alleles fell into 2 categories: missense alleles that effect the PB homeodomain (HD), and nonsense or frameshift alleles that result in C-terminal truncations of the PB protein. The phenotypic analysis of the pb homeobox missense alleles suggests that the PB HD is required for maxillary palp and proboscis development and pb - Sex combs reduced (Scr) genetic interaction. The phenotypic analysis of the pb nonsense or frameshift alleles suggests that the C-terminus is an important region required for maxillary palp and proboscis development and pb-Scr genetic interaction. PB and SCR do not interact directly with one another in a co-immunoprecipitation assay and in a yeast two-hybrid analysis, which suggests the pb-Scr genetic interaction is not mediated by a direct interaction between PB and SCR.  相似文献   
4.
Mycoplasma mastitis is often difficult to control due to a lack of rapid and accurate diagnostic tools. The aim of the current study was to develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Mycoplasma bovis (M. bovis) in mastitic milk. The assay was developed using primers designed for three different target genes: uvrC, 16S rRNA, and gyrB, and validated using mastitic milk samples previously found positive for the target pathogen. Specificity of the developed assay was determined by testing cross-reactivity of LAMP primers against closely related bovine mastitis bacterial pathogens. The sensitivity was found to be higher compared to conventional polymerase chain reaction (PCR). The LAMP assay was also capable of detecting M. bovis in PCR-negative milk samples of cows with clinical mastitis. The uvrC primers were found to be more sensitive, while gyrB primers were more specific; however, 16S rRNA primers were less specific and sensitive compared to either uvrC or gyrB primers. Cohen’s kappa values for uvrC, gyrB, and 16S rRNA primers used in the LAMP assays were 0.940, 0.970, and 0.807, respectively. There was a high level of agreement between the test results and the true-disease status as indicated by the receiver operating characteristic (ROC) curve. Our findings suggest that the newly developed LAMP assays targeting the uvrC and gyrB genes could be a useful tool for rapid and accurate diagnosis of mastitis caused by M. bovis.  相似文献   
5.
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.  相似文献   
6.
7.
Pasha Z  Haider HKh  Ashraf M 《PloS one》2011,6(8):e23667
The current protocols for generation of induced pluripotent stem (iPS) cells involve genome integrating viral vectors which may induce tumorgenesis. The aim of this study was to develop and optimize a non-viral method without genetic manipulation for reprogramming of skeletal myoblasts (SMs) using small molecules.

Methods and Results

SMs from young male Oct3/4-GFP+ transgenic mouse were treated with DNA methyltransferase (DNMT) inhibitor, RG108. Two weeks later, GFP+ colonies of SM derived iPS cells (SiPS) expressing GFP and with morphological similarity of mouse embryonic stem (ESCs) were formed and propagated in vitro. SiPS were positive for alkaline phosphatase activity, expressed SSEA1, displayed ES cell specific pluripotency markers and formed teratoma in nude mice. Optimization of culture conditions for embryoid body (EBs) formation yielded spontaneously contracting EBs having morphological, molecular, and ultra-structural similarities with cardiomyocytes and expressed early and late cardiac markers. miR profiling showed abrogation of let-7 family and upregulation of ESCs specific miR-290-295 cluster thus indicating that SiPS were similar to ESCs in miR profile. Four weeks after transplantation into the immunocompetent mice model of acute myocardial infarction (n = 12 per group), extensive myogenesis was observed in SiPS transplanted hearts as compared to DMEM controls (n = 6 per group). A significant reduction in fibrosis and improvement in global heart function in the hearts transplanted with SiPS derived cardiac progenitor cells were observed.

Conclusions

Reprogramming of SMs by DNMT inhibitor is a simple, reproducible and efficient technique more likely to generate transgene integration-free iPS cells. Cardiac progenitors derived from iPS cells propagated extensively in the infarcted myocardium without tumorgenesis and improved cardiac function.  相似文献   
8.
Many individuals cannot obtain the optimum calcium requirement from food for a variety of reasons. Therefore, calcium supplements are important sources of dietary calcium. One of the calcium sources commercially available is LactoCalcium (milk minerals) that has 28% calcium, and a 2:1 ratio of calcium to phosphorus. The objectives of this study were (a) to examine whether calcium can be released from LactoCalcium by using digestive enzymes and (b) to determine its biological activity by examining its ability to stimulate bone formation. LactoCalcium was treated in vitro by using simulated gastric and intestinal fluids or porcine gastric, pancreatic and intestinal extracts. Our results indicate the role of enzymes or bile extract in the digestion of the product. We show that, by increasing the concentration of pepsin at a fixed concentration of LactoCalcium (substrate), the percentage of released calcium increased in a dose-dependent manner, showing that, at the right enzyme concentration, as much as 100% of the calcium present in LactoCalcium can be made available. The biological activity of the digested calcium was demonstrated by the stimulation of mineralized bone nodules in SaOS-2 cells in a dose-dependent manner. Thus, 1 mM and 3 mM calcium released from LactoCalcium increased the nodule area by 23.17 mm(2) (p<0.0001) and 77.78 mm(2) (p<0.0001), respectively, as compared to a value of 0.99 mm(2) at 0.5 mM calcium from LactoCalcium. These results demonstrate the in vitro bioavailability and bioactivity of calcium from LactoCalcium and serve as a basis for carrying out in vivo analyses to determine the suitability of using LactoCalcium as a source of calcium for individuals at risk of developing osteoporosis.  相似文献   
9.
Based on a detailed study of the solubility of serum albumin, a procedure for its purification by selective ammonium sulphate precipitation has been developed. Using buffalo serum, first extraneous proteins were precipitated by making the serum 2.26 M saturated with ammonium sulphate at pH 7.0 and then albumin was precipitated from the supernatant at 1.9 M ammonium sulphate concentration at pH 4.2. The overall yield of serum albumin thus isolated was about 55% with a purity of 97%. The protein preparation gave a single nearly symmetrical peak on Sephadex G-100 column and virtually a single band on polyacrylamide gel electrophoresis in the presence and absence of SDS. Buffalo serum albumin has a molecular weight of 69,000 Da. The hydrodynamic properties such as Stoke's radius (3.70 nm), diffusion coefficient (6.03 X 10(-7) cm2/s) and frictional ratio (1.36) obtained by analytical gel chromatography, bilirubin binding characteristics and its interaction with anti-bovine serum albumin antiserum suggest that buffalo serum albumin is very similar to BSA in its molecular properties.  相似文献   
10.
Seedling hypocotyl explants ofGlycine canescens were inoculated withAgrobacterium rhizogenes carrying a chimaeric NPTII gene cointegrated into the TL-DNA of pRiA4. Transformed roots produced shoots on B5 based medium with 10.0 mgl–1 BAP, 0.05 mgl–1 IBA and 50 gml–1 kanamycin. Cultured roots and regenerated plants expressed NPTII enzyme activity which was correlated with the presence of Ri TL-DNA and the structural sequence of the NPTII gene.Abbreviations BAP 6-benzylaminopurine - BSA bovine serum albumin - DTT dithiothreitol - EDTA ethylenediaminetetraacetic acid - IBA indole-butyric acid - PAGE polyacrylamide gel electrophoresis - NPTII neomycin phosphotransferase II - PMSF phenylmethylsulphonyl fluoride - SDS sodium dodecylsulphate  相似文献   
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