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Zhou Q  Tripathi P 《Cell Stem Cell》2012,10(4):347-348
In this issue of Cell Stem Cell and in a recent issue of PNAS, Thier et?al. (2012), Han et?al. (2012), and Lujan et?al. (2012) report the derivation of multipotent neural stem/progenitor cells from cultured mouse fibroblasts using distinct reprograming approaches.  相似文献   
53.

BACKGROUND:

Idiopathic pulmonary arterial hypertension (IPAH) is a poorly understood complex disorder, which results in progressive remodeling of the pulmonary artery that ultimately leads to right ventricular failure. A two-hit hypothesis has been implicated in pathogenesis of IPAH, according to which the vascular abnormalities characteristic of PAH are triggered by the accumulation of genetic and/or environmental insults in an already existing genetic background. The multifactor dimensionality reduction (MDR) analysis is a statistical method used to identify gene–gene interaction or epistasis and gene–environment interactions that are associated with a particular disease. The MDR method collapses high-dimensional genetic data into a single dimension, thus permitting interactions to be detected in relatively small sample sizes.

AIM:

To identify and characterize polymorphisms/genes that increases the susceptibility to IPAH using MDR analysis.

MATERIALS AND METHODS:

A total of 77 IPAH patients and 100 controls were genotyped for eight polymorphisms of five genes (5HTT, EDN1, NOS3, ALK-1, and PPAR-γ2). MDR method was adopted to determine gene–gene interactions that increase the risk of IPAH.

RESULTS:

With MDR method, the single-locus model of 5HTT (L/S) polymorphism and the combination of 5HTT(L/S), EDN1(K198N), and NOS3(G894T) polymorphisms in the three-locus model were attributed to be the best models for predicting susceptibility to IPAH, with a P value of 0.05.

CONCLUSION:

MDR method can be useful in understanding the role of epistatic and gene–environmental interactions in pathogenesis of IPAH.  相似文献   
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Isolation and characterization of fluorescent pseudomonads with high phosphate-solubilizing ability is reported from the alkaline and calcium-rich soils with low P availability in the cold desert region of Lahaul and Spiti in the trans-Himalayas of India. Of 216 phosphate-solubilizing isolates, 12 exhibiting high solubilization of tricalcium phosphate (TCP) in NBRIP liquid culture were identified as Pseudomonas trivialis, P. poae, P. fluorescens, and Pseudomonas spp. on the basis of phenotypic features, whole-cell fatty acids methyl ester (FAME) profiles, and 16S rDNA sequencing. These isolates also showed relatively high solubilization of North Carolina rock phosphate (NCRP) in comparison to the solubilization of Mussoorie rock phosphate (MRP) and Udaipur rock phosphate (URP). The solubilization of phosphate substrates by P. trivialis and P. poae is reported for the first time.  相似文献   
56.
A protocol for large-scale propagation of Piper betle cvs Desawari and Desi Bangla was developed through axillary shoot proliferation. Due to systemic infection as well as high phenol content the crop was very difficult to establish in aseptic condition. But a mixture of 5 mg l?1 each of chloramphenicol and oxytetracyclin and 100 mg l?1 each of citric acid and ascorbic acid used in MS medium for 2 days helped in establishment. After 48 h, the explants were transferred to the antibiotic free medium having PVP and ascorbic acid (100 mg l?1 each), citric acid (50 mg l?1), and glutathione (20 mg l?1). Regular subculturing of the explants into liquid medium, use of antioxidants and incubation of the cultures in the dark for initial 7–10 days played a crucial role for keeping them fresh and green. Maximum numbers of axillary shoots were obtained with 2 mg l?1 BA and 0.2 mg l?1 NAA as growth supplements. The plants were rooted in 0.25 mg l?1 IBA and hardened in the soil. Phenolic compound analysis showed almost the same results in tissue-raised and in vivo grown plants in Desawari.  相似文献   
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Medical educators and patients are turning to YouTube to teach and learn about medical conditions. These videos are from authors whose credibility cannot be verified & are not peer reviewed. As a result, studies that have analyzed the educational content of YouTube have reported dismal results. These studies have been unable to exclude videos created by questionable sources and for non-educational purposes. We hypothesize that medical education YouTube videos, authored by credible sources, are of high educational value and appropriately suited to educate the public. Credible videos about cardiovascular diseases were identified using the Mayo Clinic''s Center for Social Media Health network. Content in each video was assessed by the presence/absence of 7 factors. Each video was also evaluated for understandability using the Suitability Assessment of Materials (SAM). User engagement measurements were obtained for each video. A total of 607 videos (35 hours) were analyzed. Half of all videos contained 3 educational factors: treatment, screening, or prevention. There was no difference between the number of educational factors present & any user engagement measurement (p NS). SAM scores were higher in videos whose content discussed more educational factors (p<0.0001). However, none of the user engagement measurements correlated with higher SAM scores. Videos with greater educational content are more suitable for patient education but unable to engage users more than lower quality videos. It is unclear if the notion “content is king” applies to medical videos authored by credible organizations for the purposes of patient education on YouTube.  相似文献   
59.
Plasmonics - In this paper, focus is on the light trapping surface in crystalline silicon (c-Si) solar cells where thinner c-Si wafers are expected to be used by industry to reduce the cost of cell...  相似文献   
60.
Emergence of Amsoy soybean (Glycine max) seed inoculated withSclerotinia sclerotiorum was significantly reduced below noninoculated seed at soil temperatures of 25°, 30°, and 35 °C, but not at 20 °C.S. sclerotiorum was readily reisolated from wound-inoculated stems of seedlings and nearly mature plants above the point of inoculation and below to the crown area, but not from roots. The fungus was recovered from stems but not roots of 15-day seedlings grown in sterile soil before infestation of the soil surface with a suspension of mycelium and sclerotia and assayed at 15 days after soil infestation. When compared to healthy, seeds, infected seeds withS. sclerotiorum were characterized by appearing flattened.Supported in part by the Illinois Agricultural Experiment Station; Regional Project S-72; and U.S. Agency for International Development, grant csd-1922.  相似文献   
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