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Metagentiana striata is an alpine annual herbaceous plant endemic to the east of the Qinghai–Tibet (Q–T) Plateau and adjacent areas. The phylogeography of M. striata was studied by sequencing the chloroplast DNA (cpDNA) trnS– trnG intergenic spacer. Ten haplotypes were identified from an investigation of 232 individuals of M. striata from 14 populations covering the entire geographical range of this species. The level of differentiation amongst populations was very high ( GST = 0.746; NST = 0.774) and a significant phylogeographical structure was observed ( P < 0.05). An analysis of molecular variance found a high variation amongst populations (76%), with FST = 0.762 (highly significant, P < 0.001), indicating that little gene flow occurred amongst the different regions; this was explained by the isolation of populations by high mountains along the Q–T Plateau and adjacent areas ( Nm = 0.156). Only one ancestral haplotype (A) was common and widespread throughout the distributional range of M. striata. The populations of the Hengduan Mountains region of the south-eastern Q–T Plateau showed high diversity and uniqueness of haplotypes. It is suggested that this region was the potential refugium of M. striata during the Quaternary glaciation, and that interglacial and postglacial range expansion occurred from this refugium. This scenario was in good agreement with the results of nested clade analysis, which inferred that the current spatial distribution of cpDNA haplotypes and populations resulted from range expansion, together with past allopatric fragmentation events. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 125–140. [ABSTRACT FROM AUTHOR]

We studied the phylogeography of Rhodiola alsia (Fröderström) S.H. Fu, which is a perennial herbaceous plant endemic to the Qinghai–Tibet (Q–T) Plateau, by sequencing one intergenic chloroplast spacer, rpl20–rps12 (844 bp). The sampling design included 18 populations and 315 individuals, and spanned the entire distribution range of the species. Thirty-one haplotypes were characterized, and polymorphism was observed both within and among populations. Most haplotypes were restricted to single sites or to neighbouring populations, suggesting an extremely low level of long distance gene flow via seeds. Only three haplotypes were common and widespread throughout the distributional range of R. alsia. The present geographical distribution of haplotypes probably reflects an ancient geographical pattern between the platform and southeastern margin of the Q–T Plateau identified as genetic hotspot areas. We suggest that populations of R. alsia survived in isolated refugia located in the platform and the southeastern margin of the Q–T Plateau during the Quaternary glaciation, at least during the last glaciation maximum (LGM, 32 000–16 000 years ago). The populations of R. alsia were geographically isolated by a subsequent local range expansion and independent evolution. The genetic structure of R. alsia is very different from previous phylogeographical studies of Q–T Plateau alpine plants and illustrates the importance of species-specific characteristics such as distribution areas and life-history traits which are mainly responsible for different patterns of genetic variation. Our investigation thus provides a new pattern of several refugia on the plateau platform. [ABSTRACT FROM AUTHOR]

Objective: Questions exist regarding the causal relationship between malnutrition and stroke outcomes. This study aimed to determine whether nutritional status changes or malnutrition during hospitalisation could predict 3-month outcomes in acute stroke patients.Methods: During a 10-month period, patients who suffered their first stroke within 7 days after stroke onset were included in this prospective multi-centre study. The demographic parameters, stroke risk and severity factors, malnutrition risk factors and dysphagia were recorded. Nutritional status was assessed by 3 anthropometric and 3 biochemical indices. Changes in nutritional status were defined by comparing the admission values with the 2-week values. A Modified Rankin Scale score of 3-6 was defined as a poor outcome at the 3-month follow-up. Univariate and multiple logistic regression analyses were used to investigate the power of nutritional status changes in predicting poor patient outcomes.Results: Data from 760 patients were analysed. Poor outcomes were observed in 264 (34.7%) patients. Malnutrition prevalence was 3.8% at admission and 7.5% after 2-weeks in hospital, which could not predict 3-month outcome. Emerging malnutrition was observed in 36 patients (4.7%) during the 2-week hospitalisation period and independently predicted poor 3-month outcomes after adjusting for confounding factors (odds ratio 1.37, 95% confidence interval 1.03-1.83).Conclusions: Emerging malnutrition during hospitalisation independently predicted poor 3-month outcomes in acute stroke patients in this study. [ABSTRACT FROM AUTHOR]