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Don Vu Prashant Sakharkar Eglis Tellez-Corrales Tariq Shah Ian Hutchinson David I. Min 《Molecular biology reports》2013,40(2):933-939
Polymorphism of genes encoding components of the vitamin D pathway including vitamin D receptor (VDR) and vitamin D binding protein (VDBP), have been widely explored due to the complex role played by vitamin D in renal transplant outcomes. In this study, we investigated whether polymorphisms of genes encoding VDR and VDBP were associated with allograft survival or acute rejection (AR) among a Hispanic kidney transplant population. A total of 502 Hispanic renal allograft recipients at the St. Vincent Medical Center between 2001 and 2010 were genotyped for four different single nucleotide polymorphisms of VDR: FokI C>T (rs2228570), BsmI G>A (rs1544410), ApaI T>G (rs7975232), and TaqI T>C (rs731236). We also performed genotyping for one common polymorphism in the VDBP gene (rs4588). Survival was significantly improved for patients who were homozygous GG for the rs4588 G>T allele in the VDBP gene (GG vs. GT + TT, OR = 0.63, p = 0.02) while GT genotype was associated with a higher risk of graft loss (GT vs. GG + TT, OR = 1.67, p = 0.01). We found no association for polymorphic markers in VDR with allograft survival and AR. The frequency of the haplotype GTCG (in the order of VDR FokI C>T, BsmI G>A, ApaI T>G, and TaqI T>C), was significantly different in the patients with graft rejection compared to the control (p = 0.007) while ACCA haplotype was found to be associated with graft loss (p = 0.02). Hence, the VDBP G>T polymorphism (rs4588) and two haplotypes (GTCG and ACCA) of VDR appear to be associated with renal allograft outcomes among Hispanic allograft recipients. 相似文献
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Manju Shri Arti Rai Pankaj Kumar Verma Prashant Misra Sonali Dubey Smita Kumar Sikha Verma Neelam Gautam Rudra Deo Tripathi Prabodh Kumar Trivedi Debasis Chakrabarty 《Protoplasma》2013,250(2):631-636
Agrobacterium-mediated transformation of indica rice varieties has been quite difficult as these are recalcitrant to in vitro responses. In the present study, we established a high-efficiency Agrobacterium tumefaciens-mediated transformation system of rice (Oryza sativa L. ssp. indica) cv. IR-64, Lalat, and IET-4786. Agrobacterium strain EHA-101 harboring binary vector pIG121-Hm, containing a gene encoding for β-glucuronidase (GUS) and hygromycin resistance, was used in the transformation experiments. Manipulation of different concentrations of acetosyringone, days of co-culture period, bacterial suspension of different optical densities (ODs), and the concentrations of l-cysteine in liquid followed by solid co-culture medium was done for establishing the protocol. Among the different co-culture periods, 5 days of co-culture with bacterial cells (OD600 nm?=?0.5–0.8) promoted the highest frequency of transformation (83.04 %) in medium containing l-cysteine (400 mg l?1). Putative transformed plants were analyzed for the presence of a transgene through genomic PCR and GUS histochemical analyses. Our results also suggest that different cultural conditions and the addition of l-cysteine in the co-culture medium improve the Agrobacterium-mediated transformation frequencies from an average of 12.82 % to 33.33 % in different indica rice cultivars. 相似文献
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Dong Xiao Anandan Palani Xianhai Huang Michael Sofolarides Wei Zhou Xiao Chen Robert Aslanian Zhuyan Guo James Fossetta Fang Tian Prashant Trivedi Peter Spacciapoli Charles E. Whitehurst Daniel Lundell 《Bioorganic & medicinal chemistry letters》2013,23(11):3262-3266
Conformation restriction of linear N-alkylanilide MK2 inhibitors to their E-conformer was developed. This strategy enabled rapid advance in identifying a series of potent non-ATP competitive inhibitors that exhibited cell based activity in anti-TNFα assay. 相似文献
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Ayan Dey Natalie A. Molodecky Harish Verma Prashant Sharma Jae Seung Yang Giulietta Saletti Mohammad Ahmad Sunil K. Bahl Thomas F. Wierzba Ranjan K. Nandy Jagadish M. Deshpande Roland W. Sutter Cecil Czerkinsky 《PloS one》2016,11(1)
Background
The “gold standard” for assessing mucosal immunity after vaccination with poliovirus vaccines consists in measuring virus excretion in stool after challenge with oral poliovirus vaccine (OPV). This testing is time and resource intensive, and development of alternative methods is a priority for accelerating polio eradication. We therefore evaluated circulating antibody-secreting cells (ASCs) as a potential means to evaluate mucosal immunity to poliovirus vaccine.Methods
199 subjects, aged 10 years, and previously immunized repeatedly with OPV, were selected. Subjects were assigned to receive either a booster dose of inactivated poliovirus vaccine (IPV), bivalent OPV (bOPV), or no vaccine. Using a micro-modified whole blood-based ELISPOT assay designed for field setting, circulating poliovirus type-specific IgA- and IgG-ASCs, including gut homing α4β7+ ASCs, were enumerated on days 0 and 7 after booster immunization. In addition, serum samples collected on days 0, 28 and 56 were tested for neutralizing antibody titers against poliovirus types 1, 2, and 3. Stool specimens were collected on day 28 (day of bOPV challenge), and on days 31, 35 and 42 and processed for poliovirus isolation.Results
An IPV dose elicited blood IgA- and IgG-ASC responses in 84.8 to 94.9% of subjects, respectively. In comparison, a bOPV dose evoked corresponding blood ASC responses in 20.0 to 48.6% of subjects. A significant association was found between IgA- and IgG-ASC responses and serum neutralizing antibody titers for poliovirus type 1, 2, 3 (p<0.001). In the IPV group, α4β7+ ASCs accounted for a substantial proportion of IgA-ASCs and the proportion of subjects with a positive α4β7+ IgA-ASC response to poliovirus types 1, 2 and 3 was 62.7%, 89.8% and 45.8%, respectively. A significant association was observed between virus excretion and α4β7+ IgA- and/or IgG-ASC responses to poliovirus type 3 among immunized children; however, only a weak association was found for type 1 poliovirus.Discussion
Our results suggest that virus-specific blood ASCs, especially for type 3 poliovirus, can serve as surrogate of mucosal immunity after vaccination. Further studies are needed to evaluate the duration of such memory responses and to assess the programmatic utility of this whole blood-based mucosal ASC testing for the polio eradication program. 相似文献19.
Background
Clarity of the transplanted tissue and restoration of visual acuity are the two primary metrics for evaluating the success of corneal transplantation. Participation of the transplanted eye in habitual binocular viewing is seldom evaluated post-operatively. In unilateral corneal disease, the transplanted eye may remain functionally inactive during binocular viewing due to its suboptimal visual acuity and poor image quality, vis-à-vis the healthy fellow eye.Methods and Findings
This study prospectively quantified the contribution of the transplanted eye towards habitual binocular viewing in 25 cases with unilateral transplants [40yrs (IQR: 32–42yrs) and 25 age-matched controls [30yrs (25–37yrs)]. Binocular functions including visual field extent, high-contrast logMAR acuity, suppression threshold and stereoacuity were assessed using standard psychophysical paradigms. Optical quality of all eyes was determined from wavefront aberrometry measurements.Binocular visual field expanded by a median 21% (IQR: 18–29%) compared to the monocular field of cases and controls (p = 0.63). Binocular logMAR acuity [0.0 (0.0–0.0)] almost always followed the fellow eye’s acuity [0.00 (0.00 –-0.02)] (r = 0.82), independent of the transplanted eye’s acuity [0.34 (0.2–0.5)] (r = 0.04). Suppression threshold and stereoacuity were poorer in cases [30.1% (13.5–44.3%); 620.8arc sec (370.3–988.2arc sec)] than in controls [79% (63.5–100%); 16.3arc sec (10.6–25.5arc sec)] (p<0.001). Higher-order wavefront aberrations of the transplanted eye [0.34μ (0.21–0.51μ)] were higher than the fellow eye [0.07μ (0.05–0.11μ)] (p<0.001) and their reduction with RGP contact lenses [0.09μ (0.08–0.12μ)] significantly improved the suppression threshold [65% (50–72%)] and stereoacuity [56.6arc sec (47.7–181.6arc sec)] (p<0.001).Conclusions
In unilateral corneal disease, the transplanted eye does participate in gross binocular viewing but offers limited support to fine levels of binocularity. Improvement in the transplanted eye’s optics enhances its participation in binocular viewing. Current metrics of this treatment success can expand to include measures of binocularity to assess the functional benefit of the transplantation process in unilateral corneal disease. 相似文献20.
Karthikeyan Thiyagarajan Fabio Vitali Valentina Tolaini Patrizia Galeffi Cristina Cantale Prashant Vikram Sukhwinder Singh Patrizia De Rossi Chiara Nobili Silvia Procacci Antonella Del Fiore Alessandro Antonini Ombretta Presenti Andrea Brunori 《PloS one》2016,11(3)
Phenylalanine Ammonia Lyase (PAL) gene which plays a key role in bio-synthesis of medicinally important compounds, Rutin/quercetin was sequence characterized for its efficient genomics application. These compounds possessing anti-diabetic and anti-cancer properties and are predominantly produced by Fagopyrum spp. In the present study, PAL gene was sequenced from three Fagopyrum spp. (F. tataricum, F. esculentum and F. dibotrys) and showed the presence of three SNPs and four insertion/deletions at intra and inter specific level. Among them, the potential SNP (position 949th bp G>C) with Parsimony Informative Site was selected and successfully utilised to individuate the zygosity/allelic variation of 16 F. tataricum varieties. Insertion mutations were identified in coding region, which resulted the change of a stretch of 39 amino acids on the putative protein. Our Study revealed that autogamous species (F. tataricum) has lower frequency of observed SNPs as compared to allogamous species (F. dibotrys and F. esculentum). The identified SNPs in F. tataricum didn’t result to amino acid change, while in other two species it caused both conservative and non-conservative variations. Consistent pattern of SNPs across the species revealed their phylogenetic importance. We found two groups of F. tataricum and one of them was closely related with F. dibotrys. Sequence characterization information of PAL gene reported in present investigation can be utilized in genetic improvement of buckwheat in reference to its medicinal value. 相似文献