Partitioning Clustering Based on Support Vector Ranking

Postprin

Risk factors for high-altitude headache upon acute high-altitude exposure at 3700 m in young Chinese men: a cohort study.

BackgroundThis prospective and observational study aimed to identify demographic, physiological and psychological risk factors associated with high-altitude headache (HAH) upon acute high-altitude exposure.MethodsEight hundred fifty subjects ascended by plane to 3700 m above Chengdu (500 m) over a period of two hours. Structured Case Report Form (CRF) questionnaires were used to record demographic information, physiological examinations, psychological scale, and symptoms including headache and insomnia a week before ascending and within 24 hours after arrival at 3700 m. Binary logistic regression models were used to analyze the risk factors for HAH.ResultsThe incidence of HAH was 73.3%. Age (p =0.011), physical labor intensity (PLI) (p =0.044), primary headache history (p <0.001), insomnia (p <0.001), arterial oxygen saturation (SaO2) (p =0.001), heart rate (HR) (p =0.002), the Self-Rating Anxiety Scale (SAS) (p <0.001), and the Epworth Sleepiness Scale (ESS) (p <0.001) were significantly different between HAH and non-HAH groups. Logistic regression models identified primary headache history, insomnia, low SaO2, high HR and SAS as independent risk factors for HAH.ConclusionsInsomnia, primary headache history, low SaO2, high HR, and high SAS score are the risk factors for HAH. Our findings will provide novel avenues for the study, prevention and treatment of HAH

Impacts of recent cultivation on genetic diversity pattern of a medicinal plant, Scutellaria baicalensis (Lamiaceae)

<p>Abstract</p> <p>Background</p> <p>Cultivation of medicinal plants is not only a means for meeting current and future demands for large volume production of plant-based drug and herbal remedies, but also a means of relieving harvest pressure on wild populations. <it>Scutellaria baicalensis </it>Georgi (Huang-qin or Chinese skullcap) is a very important medicinal plant in China. Over the past several decades, wild resource of this species has suffered rapid declines and large-scale cultivation was initiated to meet the increasing demand for its root. However, the genetic impacts of recent cultivation on <it>S. baicalensis </it>have never been evaluated. In this study, the genetic diversity and genetic structure of 28 wild and 22 cultivated populations were estimated using three polymorphic chloroplast fragments. The objectives of this study are to provide baseline data for preserving genetic resource of <it>S. baicalensis </it>and to evaluate the genetic impacts of recent cultivation on medicinal plants, which may be instructive to future cultivation projects of traditional Chinese medicinal plants.</p> <p>Results</p> <p>Thirty-two haplotypes of <it>S. baicalensis </it>(HapA-Y and Hap1-7) were identified when three chloroplast spacers were combined. These haplotypes constituted a shallow gene tree without obvious clusters for cultivated populations, suggesting multiple origins of cultivated <it>S. baicalensis</it>. Cultivated populations (<it>h</it>_T= 0.832) maintained comparable genetic variation with wild populations (<it>h</it>_T= 0.888), indicating a slight genetic bottleneck due to multiple origins of cultivation. However, a substantial amount of rare alleles (10 out of 25 haplotypes within wild populations) lost during the course of <it>S. baicalensis </it>cultivation. The genetic differentiation for cultivated group (<it>G</it>_ST= 0.220) was significantly lower than that of wild group (<it>G</it>_ST= 0.701). Isolation by distance analysis showed that the effect of geographical isolation on genetic structure was significant in wild populations (<it>r </it>= 0.4346, <it>P </it>< 0.0010), but not in cultivated populations (<it>r = </it>0.0599, <it>P </it>= 0.2710). These genetic distribution patterns suggest that a transient cultivation history and the extensive seed change among different geographical areas during the course of <it>S. baicalensis </it>cultivation.</p> <p>Conclusions</p> <p>Although cultivated <it>S. baicalensis </it>maintains comparable genetic diversity relative to wild populations, recent cultivation has still imposed profound impacts on genetic diversity patterns of the cultivated <it>S. baicalensis </it>populations, i.e., the loss of rare alleles and homogenization of cultivated populations. This study suggests that conservation-by-cultivation is an effective means for protecting genetic resources of <it>S. baicalensis</it>, however, the wild resources still need to be protected <it>in situ </it>and the evolutionary consequences of extensive seed exchange mediated by human being should be monitored carefully.</p

6-Chloro-3-nitro-N-(propan-2-yl)pyridin-2-amine

There are two mol­ecules in the asymmetric unit mol­ecule of the title compound, C8H10ClN3O2. Intra­molecular N—H⋯O hydrogen bonds stabilize the mol­ecular structure. There are no classical inter­molecular hydrogen bonds in the crystal structure

CMTM2 is essential for spermiogenesis in mice

Objective: This study is to investigate whether CKLF-like MARVEL transmembrane domain-containing protein 2 (CMTM2) is involved in spermatogenesis in mice. CMTM2 is highly expressed in testis, and could possibly a potential spermagogenesis specific gene. Methods: CMTM2-deficient mouse model was generated. Northern, RT-PCR and Western blotting analysis were performed on total RNA derived from wild-type (WT, CMTM2(+/+)) and CMTM2(+/-)(heterozygote) and CMTM2(-/-)(homozygote) mice to examine the CMTM2 level. The number of litters and the number of pups were counted and pregnancy rates calculated. The motility and morphology of the sperm and the histology of testes were analyzed. Serum testosterone and FSH concentrations were also measured. Standard t-tests (Excel, Microsoft, Redmond, WA, USA) were used and standard error of means were calculated. Results: CMTM2 is highly expressed in a finely regulated pattern in the mouse testis during spermatogenesis. The body weight of adult mice with CMTM2 deficiency was not significantly different from that of wild type mice. No obvious anatomical or behavioral abnormalities were observed. The testes of CMTM2(-/-)were smaller than that of CMTM2(+/+) mice. Female CMTM2 null mice are fertile, indicating that CMTM2 is not required for female gametogenesis. The CMTM2(-/-)mice produced virtually no sperm, and CMTM2(+/-)mice sperm count showed a significant decline. The hormone levels are not significantly different. The CMTM2(-/-)male mice are sterile due to a late, complete arrest of spermiogenesis. The organized architecture of the seminiferous epithelium of the seminiferous tubules seen in CMTM2(+/+) mice was lost in CMTM2(-/-)mice. Conclusions: This study suggests CMTM2 is not required for embryonic development in the mouse but is essential for spermiogenesis.NIH [AG14875]; Specialized Research Fund for the Doctoral Program of Higher Education, China [20-120001120056]SCI(E)[email protected]

Identification of Predictive Pathways for Non-Hodgkin Lymphoma Prognosis

Despite decades of intensive research, NHL (non-Hodgkin lymphoma) still remains poorly understood and is largely incurable. Recent molecular studies suggest that genomic variants measured with SNPs (single nucleotide polymorphisms) in genes may have additional predictive power for NHL prognosis beyond clinical risk factors. We analyzed a genetic association study. The prognostic cohort consisted of 346 patients, among whom 138 had DLBCL (diffuse large B-cell lymphoma) and 101 had FL ( follicular lymphoma). For DLBCL, we analyzed 1229 SNPs which represented 122 KEGG pathways. For FL, we analyzed 1228 SNPs which represented 122 KEGG pathways. Unlike in existing studies, we targeted at identifying pathways with significant additional predictive power beyond clinical factors. In addition, we accounted for the joint effects of multiple SNPs within pathways, whereas some existing studies drew pathway-level conclusions based on separate analysis of individual SNPs. For DLBCL, we identified four pathways, which, combined with the clinical factors, had medians of the prediction logrank statistics as 2.535, 2.220, 2.094, 2.453, and 2.512, respectively. As a comparison, the clinical factors had a median of the prediction logrank statistics around 0.552. For FL, we identified two pathways, which, combined with the clinical factors, had medians of the prediction logrank statistics as 4.320 and 3.532, respectively. As a comparison, the clinical factors had a median of the prediction logrank statistics around 1.212. For NHL overall, we identified three pathways, which, combined with the clinical factors, had medians of the prediction logrank statistics as 5.722, 5.314, and 5.441, respective. As a comparison, the clinical factors had a median of the prediction logrank statistics around 4.411. The identified pathways have sound biological bases. In addition, they are different from those identified using existing approaches. They may provide further insights into the biological mechanisms underlying the prognosis of NHL

Hemoconcentration is associated with early faster fluid rate and increased risk of persistent organ failure in acute pancreatitis patients.

Background:Controversies existed surrounding the use of hematocrit to guide early fluid therapy in acute pancreatitis (AP). The association between hematocrit, early fluid therapy, and clinical outcomes in ward AP patients needs to be investigated. Methods:Data from prospectively maintained AP database and retrospectively collected details of fluid therapy were analyzed. Patients were stratified into three groups: Group 1, hematocrit 44% at 24 h; Group 3: hematocrit >44% on admission and decreased thereafter during first 24 h. "Early" means first 24 h after admission. Baseline characteristics, early fluid rates, and clinical outcomes of the three groups were compared. Results:Among the 628 patients, Group 3 had a higher hematocrit level, greater baseline predicted severity, faster fluid rate, and more fluid volume in the first 24 h compared with Group 1 or 2. Group 3 had an increased risk for persistent organ failure (POF; odds ratio 2, 95% confidence interval [1.1-3.8], P = 0.03) compared with Group 1 after adjusting for difference in baseline clinical severity scores, there was no difference between Group 2 and Group 3 or Group 1. Multivariate regression analyses revealed that hemoconcentration and early faster fluid rate were risk factors for POF and mortality (both P < 0.05). Conclusions:Hemoconcentration is associated with faster fluid rate and POF in ward AP patients. Randomized trials comparing standardized early fast and slow fluid management is warranted