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1.
The value of genome-specific repetitive DNA sequences for use as molecular markers in studying genome differentiation was investigated. Five repetitive DNA sequences from wild species of rice were cloned. Four of the clones, pOm1, pOm4, pOmA536, and pOmPB10, were isolated from Oryza minuta accession 101141 (BBCC genomes), and one clone, pOa237, was isolated from Oryza australiensis accession 100882 (EE genome). Southern blot hybridization to different rice genomes showed strong hybridization of all five clones to O. minuta genomic DNA and no cross hybridization to genomic DNA from Oryza sativa (AA genome). The pOm1 and pOmA536 sequences showed cross hybridization only to all of the wild rice species containing the C genome. However, the pOm4, pOmPB10, and pOa237 sequences showed cross hybridization to O. australiensis genomic DNA in addition to showing hybridization to the O. minuta genomic DNA. 相似文献
2.
Nucleophilic addition of 4-methoxy-alpha-toluenethiol to capped cyclodextrins followed by deprotection in TFA affords cyclodextrin dithiols in good yields with no disulfide formation and requires only minimal purification. 相似文献
3.
Qing Lin Ling Song Poon Junling Chen Linan Cheng Basil HoYuen Peter CK Leung 《Reproductive biology and endocrinology : RB&E》2009,7(1):115-8
Background
Obesity has been linked to an increased risk of female infertility. Leptin, an adipocytokine which is elevated during obesity, may influence gonadal function through modulating steroidogenesis in granulosa cells. 相似文献4.
Yangbo Sun Chao Qiang Jiang Kar Keung Cheng Wei Sen Zhang Gabriel M. Leung Tai Hing Lam C. Mary Schooling 《PloS one》2015,10(8)
Objective
To examine the adjusted associations of fruit consumption and vegetable consumption with the Framingham score and its components in the non-Western setting of Southern China, considering health status.Method
Linear regression was used to assess the cross-sectional associations of fruit and vegetable consumption with the Framingham score and its components, among 19,518 older Chinese (≥50 years) from the Guangzhou Biobank Cohort Study in Southern China (2003–2006), and whether these differed by health status.Results
The association of fruit consumption with the Framingham score varied by health status (P-value<0.001), but not vegetable consumption (P-value 0.51). Fruit consumption was associated with a lower Framingham score (-0.04 per portions/day, 95% confidence interval (CI) -0.08 to -0.004) among participants in poor health, adjusted for age, sex, recruitment phase, socio-economic position and lifestyle. However, similarly adjusted, fruit consumption was associated with a higher Framingham score (0.05, 95% CI 0.02 to 0.09) among participants in good health, perhaps due to a positive association of fruit consumption with fasting glucose. Similarly adjusted, vegetable consumption was associated with a higher Framingham score (0.03, 95% CI 0.01 to 0.05) among all participants, with no difference by health status.Conclusion
This large study from a non-western setting found that fruit and vegetable consumption was barely associated with the Framingham score, or major CVD risk factors. 相似文献5.
6.
Cheuk-Chun Szeto Bonnie Ching-Ha Kwan Kai-Ming Chow Jeffrey Sung-Shing Kwok Ka-Bik Lai Phyllis Mei-Shan Cheng Wing-Fai Pang Jack Kit-Chung Ng Michael Ho-Ming Chan Lydia Choi-Wan Lit Chi-Bon Leung Philip Kam-Tao Li 《PloS one》2015,10(5)
BackgroundCirculating bacterial DNA fragment is related to systemic inflammatory state in peritoneal dialysis (PD) patients. We hypothesize that plasma bacterial DNA level predicts cardiovascular events in new PD patients.MethodsWe measured plasma bacterial DNA level in 191 new PD patients, who were then followed for at least a year for the development of cardiovascular event, hospitalization, and patient survival.ResultsThe average age was 59.3 ± 11.8 years; plasma bacterial DNA level 34.9 ± 1.5 cycles; average follow up 23.2 ± 9.7 months. At 24 months, the event-free survival was 86.1%, 69.8%, 55.4% and 30.8% for plasma bacterial DNA level quartiles I, II, III and IV, respectively (p < 0.0001). After adjusting for confounders, plasma bacterial DNA level, baseline residual renal function and malnutrition-inflammation score were independent predictors of composite cardiovascular end-point; each doubling in plasma bacterial DNA level confers a 26.9% (95% confidence interval, 13.0 – 42.5%) excess in risk. Plasma bacterial DNA also correlated with the number of hospital admission (r = -0.379, p < 0.0001) and duration of hospitalization for cardiovascular reasons (r = -0.386, p < 0.0001). Plasma bacterial DNA level did not correlate with baseline arterial pulse wave velocity (PWV), but with the change in carotid-radial PWV in one year (r = -0.238, p = 0.005).ConclusionsCirculating bacterial DNA fragment level is a strong predictor of cardiovascular event, need of hospitalization, as well as the progressive change in arterial stiffness in new PD patients. 相似文献
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Ronghai Cheng Ross Ka-Kit Leung Yao Chen Yidan Pan Yin Tong Zhoufang Li Luwen Ning Xuefeng B. Ling Jiankui He 《PloS one》2015,10(10)
We present Virtual Pharmacist, a web-based platform that takes common types of high-throughput data, namely microarray SNP genotyping data, FASTQ and Variant Call Format (VCF) files as inputs, and reports potential drug responses in terms of efficacy, dosage and toxicity at one glance. Batch submission facilitates multivariate analysis or data mining of targeted groups. Individual analysis consists of a report that is readily comprehensible to patients and practioners who have basic knowledge in pharmacology, a table that summarizes variants and potential affected drug response according to the US Food and Drug Administration pharmacogenomic biomarker labeled drug list and PharmGKB, and visualization of a gene-drug-target network. Group analysis provides the distribution of the variants and potential affected drug response of a target group, a sample-gene variant count table, and a sample-drug count table. Our analysis of genomes from the 1000 Genome Project underlines the potentially differential drug responses among different human populations. Even within the same population, the findings from Watson’s genome highlight the importance of personalized medicine. Virtual Pharmacist can be accessed freely at http://www.sustc-genome.org.cn/vp or installed as a local web server. The codes and documentation are available at the GitHub repository (https://github.com/VirtualPharmacist/vp). Administrators can download the source codes to customize access settings for further development. 相似文献
10.
Joseph C. Y. Liu Janice M. Leung David A. Ngan Negar F. Nashta Silvia Guillemi Marianne Harris Viviane D. Lima Soo-Jung Um Yuexin Li Sheena Tam Tawimas Shaipanich Rekha Raju Cameron Hague Jonathon A. Leipsic Jean Bourbeau Wan C. Tan P. Richard Harrigan Don D. Sin Julio Montaner S. F. Paul Man 《PloS one》2015,10(4)
Combination antiretroviral therapy (cART) has extended the longevity of human immunodeficiency virus (HIV)-infected individuals. However, this has resulted in greater awareness of age-associated diseases such as chronic obstructive pulmonary disease (COPD). Accelerated cellular senescence may be responsible, but its magnitude as measured by leukocyte telomere length is unknown and its relationship to HIV-associated COPD has not yet been established. We measured absolute telomere length (aTL) in peripheral leukocytes from 231 HIV-infected adults. Comparisons were made to 691 HIV-uninfected individuals from a population-based sample. Subject quartiles of aTL were assessed for relationships with measures of HIV disease severity, airflow obstruction, and emphysema severity on computed tomographic (CT) imaging. Multivariable regression models identified factors associated with shortened aTL. Compared to HIV-uninfected subjects, the mean aTL in HIV-infected patients was markedly shorter by 27 kbp/genome (p<0.001); however, the slopes of aTL vs. age were not different (p=0.469). Patients with longer known durations of HIV infection (p=0.019) and lower nadir CD4 cell counts (p=0.023) had shorter aTL. Shorter aTL were also associated with older age (p=0.026), smoking (p=0.005), reduced forced expiratory volume in one second (p=0.030), and worse CT emphysema severity score (p=0.049). HIV-infected subjects demonstrate advanced cellular aging, yet in a cART-treated cohort, the relationship between aTL and age appears no different from that of HIV-uninfected subjects. 相似文献