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Yi Dong Wenjie Cao Jinma Ren Deepak S. Nair Sarah Parker Jan L. Jahnel Teresa G. Swanson-Devlin Judith M. Beck Maureen Mathews Clayton J. McNeil Manas Upadhyaya Yuan Gao Qiang Dong David Z. Wang 《PloS one》2015,10(8)
Intravenous (IV) tissue-type plasminogen activator (tPA) is the only approved noninvasive therapy for acute ischemic stroke (AIS). However, after tPA treatment, the outcome of patients with different subtypes of stroke according to their vascular risk factors remains to be elucidated. We aim to explore the relationship between the outcome and different risk factors in patients with different subtype of acute strokes treated with IV tPA. Records of patients in this cohort were reviewed. Data collected and analysed included the demographics, vascular risk factors, baseline National Institutes of Health Stroke Scale (NIHSS) scores, 90-day modified Rankin Scores (mRS), and subtypes of stroke. By using the 90-day mRS, patients were dichotomized into favorable versus unfavorable outcome in each subtype of stroke. We identified the vascular risk factors that are likely associated with the poor outcome in each subtype. Among 570 AIS patients received IV tPA, 217 were in the large artery atherosclerosis (LAA) group, 146 in the small vessel occlusion(SVO) group, and 140 in the cardioaortic embolism(CE) group. Lower NIHSS score on admission was related to favorable outcome in patients in all subtypes. Patients with history of dyslipidemia were likely on statin treatment before their admission and hence less likely to have elevated cholesterol level on admission. Therefore, there was a possible paradoxical effect on the outcome in patients with LAA and SVO subtypes of strokes. SVO patients with history of diabetes had higher risk of unfavorable outcome. SVO patients had favorable outcome if their time from onset to treatment was short. In conclusion, the outcome of patients treated with IV tPA may be related to different vascular risk factors associated with different subtypes of stroke. 相似文献
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Enhanced ascorbic acid accumulation in transgenic potato confers tolerance to various abiotic stresses 总被引:2,自引:0,他引:2
Hemavathi Chandrama Prakash Upadhyaya Nookaraju Akula Ko Eun Young Se Chul Chun Doo Hwan Kim Se Won Park 《Biotechnology letters》2010,32(2):321-330
l-Ascorbic acid (Vitamin C, AsA) is an important component of human nutrition. Plants and several animals can synthesize their
own ascorbic acid, whereas humans lack the gene essential for ascorbic acid biosynthesis and must acquire from their diet.
In the present study, we developed transgenic potato (Solanum tuberosum L. cv. Taedong Valley) over-expressing l-gulono-γ-lactone oxidase (GLOase gene; NCBI Acc. No. NM022220), isolated from rat cells driven by CaMV35S constitutive promoter
that showed enhanced AsA accumulation. Molecular analyses of four independent transgenic lines performed by PCR, Southern
and RT-PCR revealed the stable integration of the transgene in the progeny. The transformation frequency was ca. 7.5% and
the time required for the generation of transgenic plants was 6–7 weeks. Transgenic tubers showed significantly enhanced AsA
content (141%) and GLOase activity as compared to untransformed tubers. These transgenics were also found to withstand various
abiotic stresses caused by Methyl Viologen (MV), NaCl or mannitol, respectively. The T1 transgenic plants exposed to salt stress (100 mM NaCl) survived better with increased shoot and root length when compared
to untransformed plants. The elevated level of AsA accumulation in transgenics was directly correlated with their ability
to withstand abiotic stresses. These results further demonstrated that the overexpression of GLOase gene enhanced basal levels of AsA in potato tubers and also the transgenics showed better survival under various abiotic
stresses. 相似文献
247.
Sangam L. Dwivedi Enrico Perotti Hari D. Upadhyaya Rodomiro Ortiz 《Sexual plant reproduction》2010,23(4):265-279
Arabidopsis, Mimulus and tomato have emerged as model plants in researching genetic and molecular basis of differences in mating systems. Variations
in floral traits and loss of self-incompatibility have been associated with mating system differences in crops. Genomics research
has advanced considerably, both in model and crop plants, which may provide opportunities to modify breeding systems as evidenced
in Arabidopsis and tomato. Mating system, however, not recombination per se, has greater effect on the level of polymorphism. Generating
targeted recombination remains one of the most important factors for crop genetic enhancement. Asexual reproduction through
seeds or apomixis, by producing maternal clones, presents a tremendous potential for agriculture. Although believed to be
under simple genetic control, recent research has revealed that apomixis results as a consequence of the deregulation of the
timing of sexual events rather than being the product of specific apomixis genes. Further, forward genetic studies in Arabidopsis have permitted the isolation of novel genes reported to control meiosis I and II entry. Mutations in these genes trigger
the production of unreduced or apomeiotic megagametes and are an important step toward understanding and engineering apomixis. 相似文献
248.
Gargi Roy Elaine M. Chalfin Anita Saxena Xiaodong Wang 《Molecular biology of the cell》2010,21(4):597-609
Multiple mutations in cystic fibrosis transmembrane conductance regulator (CFTR) impair its exit from the endoplasmic reticulum (ER). We compared two processing mutants: ΔF508 and the ER exit code mutant DAA. Although both have severe kinetic processing defect, DAA but not ΔF508 has substantial accumulation in its mature form, leading to higher level of processing at the steady state. DAA has much less profound conformational abnormalities. It has lower Hsp70 association and higher post-ER stability than ΔF508. The ER exit code is necessary for ΔF508 residual export and rescue. R555K, a mutation that rescues ΔF508 misprocessing, improves Sec24 association and enhances its post-ER stability. Using in situ limited proteolysis, we demonstrated a clear change in trypsin sensitivity in ΔF508 NBD1, which is reversed, together with that of other domains, by low temperature, R555K or both. We observed a conversion of the proteolytic pattern of DAA from the one resembling ΔF508 to the one similar to wild-type CFTR during its maturation. Low temperature and R555K are additive in improving ΔF508 conformational maturation and processing. Our data reveal a dual contribution of ER exit code and domain conformation to CFTR misprocessing and underscore the importance of conformational repair in effective rescue of ΔF508. 相似文献
249.
Ravi Koppolu Hari D Upadhyaya Sangam L Dwivedi David A Hoisington Rajeev K Varshney 《BMC plant biology》2010,10(1):15
Background
The genus Arachis, originated in South America, is divided into nine taxonomical sections comprising of 80 species. Most of the Arachis species are diploids (2n = 2x = 20) and the tetraploid species (2n = 2x = 40) are found in sections Arachis, Extranervosae and Rhizomatosae. Diploid species have great potential to be used as resistance sources for agronomic traits like pests and diseases, drought related traits and different life cycle spans. Understanding of genetic relationships among wild species and between wild and cultivated species will be useful for enhanced utilization of wild species in improving cultivated germplasm. The present study was undertaken to evaluate genetic relationships among species (96 accessions) belonging to seven sections of Arachis by using simple sequence repeat (SSR) markers developed from Arachis hypogaea genomic library and gene sequences from related genera of Arachis. 相似文献250.
Gargi Bagchi Yijing Zhang David J Waxman 《Reproductive biology and endocrinology : RB&E》2010,8(1):65