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81.
Bernadette Boutard Marie-Louise Bouillant Jean Chopin Philippe Lebreton 《Biochemical Systematics and Ecology》1973,1(3):133-140
The flavonoid patterns of twenty-three species of Fluviales (= Helobieae) were determined. Flavonols and pro-anthocyanidins are uncommon and trihydroxy derivatives are absent. In contrast, flavones (luteolin and chrysoeriol derivatives) are common, often as C-glycosides (Alismataceae, Butomaceae, Potamogetonaceae). From a taxonomic point of view the results suggest that the Fluviales can be divided into two groups: Potamogetonaceae. Zosteraceae, Ruppiaceae, Zanichelliaceae and Juncaginaceae forming the first, and Hydrocharitaceae, Butomaceae. Alismataceae and Aponogetonaceae the second. This arrangement agrees for the most part with the views of Emberger and Takhtajan.
Résumé
Le contenu flavonique de 23 Fluviales (= Hélobiées) a été analysé. Flavonols et leuco-anthocyanes sont rares, les dérivés phényl-trihydroxylés absents. Les flavones, par contre, sont fréquentes (lutéoline, chrysoériol). notamment sous forme de C-glycosides (Alismatacées, Butomacées, Potamogétonacées). D'un point de vue taxinomique, les résultats permettent de regrouper, d'une part Potamogétonacées, Zostéracées, Ruppiacées. Zanichelliacées et Juncaginacées; d'autre part Hydrocharitacées, Butomacées, Alismatacées et Aponogétonacées. Cette proposition s'accorde dans ses grandes lignes avec les rues des botanistes Emberger et Takhtajan. 相似文献82.
Jeffrey Q. Chambers Amanda L. Robertson Vilany M. C. Carneiro Adriano J. N. Lima Marie-Louise Smith Lucie C. Plourde Niro Higuchi 《Oecologia》2009,160(1):107-117
Advanced recruitment and neutral processes play important roles in determining tree species composition in tropical forest
canopy gaps, with few gaps experiencing clear secondary successional processes. However, most studies are limited to the relatively
limited spatial scales provided by forest inventory plots, and investigations over the entire range of gap size are needed
to better understand how ecological processes vary with tree mortality events. This study employed a landscape approach to
test the hypothesis that tree species composition and forest structural attributes differ between large blowdown gaps and
relatively undisturbed primary forest. Spectral mixture analysis on hyperspectral satellite imagery was employed to direct
field sampling to widely distributed sites, and blowdown plots were compared with undisturbed primary forest plots. Tree species
composition and forest structural attributes differed markedly between gap and non-gap sites, providing evidence of niche
partitioning in response to disturbance across the region. Large gaps were dominated by classic Neotropical pioneer genera
such as Cecropia and Vismia, and average tree size was significantly smaller. Mean wood density of trees recovering in large gaps (0.55 g cm−3) was significantly lower than in primary forest plots (0.71 g cm−3), a difference similar to that found when comparing less dynamic (i.e., tree recruitment, growth, and mortality) Central
Amazon forests with more dynamic Western Amazon forests. Based on results, we hypothesize that the importance of neutral processes
weaken, and niche processes strengthen, in determining community assembly along a gradient in gap size and tree mortality
intensity. Over evolutionary time scales, pervasive dispersal among colonizers could result in the loss of tree diversity
in the pioneer guild through competitive exclusion. Results also underscore the importance of considering disturbance processes
across the landscape when addressing forest carbon balance. 相似文献
83.
Cord Drögemüller Marco Rossi Arcangelo Gentile Stefania Testoni Hannes Jörg Gerald Stranzinger Michaela Drögemüller Marie-Louise Glowatzki-Mullis Tosso Leeb 《Mammalian genome》2009,20(1):53-59
Arachnomelia in Brown Swiss cattle is a monogenic autosomal recessive inherited congenital disorder of the skeletal system
giving affected calves a spidery look (OMIA ID 000059). Over a period of 20 years 15 cases were sampled in the Swiss and Italian
Brown cattle population. Pedigree data revealed that all affected individuals trace back to a single acknowledged carrier
founder sire. A genome scan using 240 microsatellites spanning the 29 bovine autosomes showed homozygosity at three adjacent
microsatellite markers on bovine Chr 5 in all cases. Linkage analysis confirmed the localization of the arachnomelia mutation
in the region of the marker ETH10. Fine-mapping and haplotype analysis using a total of 34 markers in this region refined the critical region of the arachnomelia
locus to a 7.19-Mb interval on bovine Chr 5. The disease-associated IBD haplotype was shared by 36 proven carrier animals
and allows marker-assisted selection. As the corresponding human and mouse chromosome segments do not contain any clear functional
candidate genes for this disorder, the mutation causing arachnomelia in the Brown Swiss cattle might help to identify an unknown
gene in bone development.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
84.
85.
Ivan Dimitrijevic Marie-Louise Edvinsson Qingwen Chen Malin Malmsjö Per-Ola Kimblad Lars Edvinsson 《BMC cardiovascular disorders》2009,9(1):1-11
Background
Endothelin-1 and angiotensin II are strong vasoconstrictors. Patients with ischemic heart disease have elevated plasma levels of endothelin-1 and angiotensin II and show increased vascular tone. The aim of the present study was to examine the endothelin and angiotensin II receptor expression in subcutaneous arteries from patients with different degrees of ischemic heart disease.Methods
Subcutaneous arteries were obtained, by biopsy from the abdomen, from patients undergoing coronary artery bypass graft (CABG) surgery because of ischemic heart disease (n = 15), patients with angina pectoris without established myocardial infarction (n = 15) and matched cardiovascular healthy controls (n = 15). Endothelin type A (ETA) and type B (ETB), and angiotensin type 1 (AT1) and type 2 (AT2) receptors expression and function were examined using immunohistochemistry, Western blot and in vitro pharmacology.Results
ETA and, to a lesser extent, ETB receptor staining was observed in the healthy vascular smooth muscle cells. The level of ETB receptor expression was higher in patients undergoing CABG surgery (250% ± 23%; P < 0.05) and in the patients with angina pectoris (199% ± 6%; P < 0.05), than in the healthy controls (100% ± 28%). The data was confirmed by Western blotting. Arteries from CABG patients showed increased vasoconstriction upon administration of the selective ETB receptor agonist sarafotoxin S6c, compared to healthy controls (P < 0.05). No such difference was found for the ETA receptors. AT1 and, to a lesser extent, AT2 receptor immunostaining was seen in the vascular smooth muscle cells. The level of AT1 receptor expression was higher in both the angina pectoris (128% ± 25%; P < 0.05) and in the CABG patients (203% ± 41%; P < 0.05), as compared to the healthy controls (100% ± 25%). The increased AT1 receptor expression was confirmed by Western blotting. Myograph experiment did however not show any change in vasoconstriction to angiotensin II in CABG patients compared to healthy controls (P = n.s).Conclusion
The results demonstrate, for the first time, upregulation of ETB and AT1 receptors in vascular smooth muscle cells in ischemic heart disease. These receptors may play a role in the pathophysiology of ischemic heart disease and could provide important targets for pharmaceutical interventions. 相似文献86.
Michael D. Moore Olga A. Nikolaitchik Jianbo Chen Marie-Louise Hammarskj?ld David Rekosh Wei-Shau Hu 《PLoS pathogens》2009,5(10)
Once transcribed, the nascent full-length RNA of HIV-1 must travel to the appropriate host cell sites to be translated or to find a partner RNA for copackaging to form newly generated viruses. In this report, we sought to delineate the location where HIV-1 RNA initiates dimerization and the influence of the RNA transport pathway used by the virus on downstream events essential to viral replication. Using a cell-fusion-dependent recombination assay, we demonstrate that the two RNAs destined for copackaging into the same virion select each other mostly within the cytoplasm. Moreover, by manipulating the RNA export element in the viral genome, we show that the export pathway taken is important for the ability of RNA molecules derived from two viruses to interact and be copackaged. These results further illustrate that at the point of dimerization the two main cellular export pathways are partially distinct. Lastly, by providing Gag in trans, we have demonstrated that Gag is able to package RNA from either export pathway, irrespective of the transport pathway used by the gag mRNA. These findings provide unique insights into the process of RNA export in general, and more specifically, of HIV-1 genomic RNA trafficking. 相似文献
87.
Gangwei Ou Pramod Kumar Rompikuntal Aziz Bitar Barbro Lindmark Karolis Vaitkevicius Sun Nyunt Wai Marie-Louise Hammarstr?m 《PloS one》2009,4(11)
Background
Vibrio cholerae is the causal intestinal pathogen of the diarrheal disease cholera. It secretes the protease PrtV, which protects the bacterium from invertebrate predators but reduces the ability of Vibrio-secreted factor(s) to induce interleukin-8 (IL-8) production by human intestinal epithelial cells. The aim was to identify the secreted component(s) of V. cholerae that induces an epithelial inflammatory response and to define whether it is a substrate for PrtV.Methodology/Principal Findings
Culture supernatants of wild type V. cholerae O1 strain C6706, its derivatives and pure V. cholerae cytolysin (VCC) were analyzed for the capacity to induce changes in cytokine mRNA expression levels, IL-8 and tumor necrosis factor-α (TNF-α) secretion, permeability and cell viability when added to the apical side of polarized tight monolayer T84 cells used as an in vitro model for human intestinal epithelium. Culture supernatants were also analyzed for hemolytic activity and for the presence of PrtV and VCC by immunoblot analysis.Conclusions/Significance
We suggest that VCC is capable of causing an inflammatory response characterized by increased permeability and production of IL-8 and TNF-α in tight monolayers. Pure VCC at a concentration of 160 ng/ml caused an inflammatory response that reached the magnitude of that caused by Vibrio-secreted factors, while higher concentrations caused epithelial cell death. The inflammatory response was totally abolished by treatment with PrtV. The findings suggest that low doses of VCC initiate a local immune defense reaction while high doses lead to intestinal epithelial lesions. Furthermore, VCC is indeed a substrate for PrtV and PrtV seems to execute an environment-dependent modulation of the activity of VCC that may be the cause of V. cholerae reactogenicity. 相似文献88.
Makandwe Nyirenda Basia Zaba Till B?rnighausen Victoria Hosegood Marie-Louise Newell 《PloS one》2010,5(8)
Background
The main source of HIV prevalence estimates are household and population-based surveys; however, high refusal rates may hinder the interpretation of such estimates. The study objective was to evaluate whether population HIV prevalence estimates can be adjusted for survey non-response using mortality rates.Methodology/Principal Findings
Data come from the longitudinal Africa Centre Demographic Information System (ACDIS), in rural South Africa. Mortality rates for persons tested and not tested in the 2005 HIV surveillance were available from routine household surveillance. Assuming HIV status among individuals contacted but who refused to test (non-response) is missing at random and mortality among non-testers can be related to mortality of those tested a mathematical model was developed. Non-parametric bootstrapping was used to estimate the 95% confidence intervals around the estimates. Mortality rates were higher among untested (16.9 per thousand person-years) than tested population (11.6 per thousand person-years), suggesting higher HIV prevalence in the former. Adjusted HIV prevalence for females (15–49 years) was 31.6% (95% CI 26.1–37.1) compared to observed 25.2% (95% CI 24.0–26.4). For males (15–49 years) adjusted HIV prevalence was 19.8% (95% CI 14.8–24.8), compared to observed 13.2% (95% CI 12.1–14.3). For both sexes (15–49 years) combined, adjusted prevalence was 27.5% (95% CI 23.6–31.3), and observed prevalence was 19.7% (95% CI 19.6–21.3). Overall, observed prevalence underestimates the adjusted prevalence by around 7 percentage points (37% relative difference).Conclusions/Significance
We developed a simple approach to adjust HIV prevalence estimates for survey non-response. The approach has three features that make it easy to implement and effective in adjusting for selection bias than other approaches. Further research is needed to assess this approach in populations with widely available HIV treatment (ART). 相似文献89.
Josephine V. J. Lightowler Graham S. Cooke Portia Mutevedzi Richard J. Lessells Marie-Louise Newell Martin Dedicoat 《PloS one》2010,5(1)
Background
Cryptococcal meningitis (CM) remains a leading cause of death for HIV-infected individuals in sub-Saharan Africa. Improved treatment strategies are needed if individuals are to benefit from the increasing availability of antiretroviral therapy. We investigated the factors associated with mortality in routine care in KwaZulu-Natal, South Africa.Methodology/Principal Findings
A prospective year long, single-center, consecutive case series of individuals diagnosed with cryptococcal meningitis 190 patients were diagnosed with culture positive cryptococcal meningitis, of whom 186 were included in the study. 52/186 (28.0%) patients died within 14 days of diagnosis and 60/186 (32.3%) had died by day 28. In multivariable cox regression analysis, focal neurology (aHR 11 95%C.I. 3.08–39.3, P<0.001), diastolic blood pressure <60 mmHg (aHR 2.37 95%C.I. 1.11–5.04, P = 0.025), concurrent treatment for tuberculosis (aHR 2.11 95%C.I. 1.02–4.35, P = 0.044) and use of fluconazole monotherapy (aHR 3.69 95% C.I. 1.74–7.85, P<0.001) were associated with increased mortality at 14 and 28 days.Conclusions
Even in a setting where amphotericin B is available, mortality from cryptococcal meningitis in this setting is high, particularly in the immediate period after diagnosis. This highlights the still unmet need not only for earlier diagnosis of HIV and timely access to treatment of opportunistic infections, but for better treatment strategies of cryptococcal meningitis. 相似文献90.
Roncarati R Latronico MV Musumeci B Aurino S Torella A Bang ML Jotti GS Puca AA Volpe M Nigro V Autore C Condorelli G 《Journal of cellular physiology》2011,226(11):2894-2900
Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiac disease. Fourteen sarcomeric and sarcomere‐related genes have been implicated in HCM etiology, those encoding β‐myosin heavy chain (MYH7) and cardiac myosin binding protein C (MYBPC3) reported as the most frequently mutated: in fact, these account for around 50% of all cases related to sarcomeric gene mutations, which are collectively responsible for approximately 70% of all HCM cases. Here, we used denaturing high‐performance liquid chromatography followed by bidirectional sequencing to screen the coding regions of MYH7 and MYBPC3 in a cohort (n = 125) of Italian patients presenting with HCM. We found 6 MHY7 mutations in 9/125 patients and 18 MYBPC3 mutations in 19/125 patients. Of the three novel MYH7 mutations found, two were missense, and one was a silent mutation; of the eight novel MYBPC3 mutations, one was a substitution, three were stop codons, and four were missense mutations. Thus, our cohort of Italian HCM patients did not harbor the high frequency of mutations usually found in MYH7 and MYBPC3. This finding, coupled to the clinical diversity of our cohort, emphasizes the complexity of HCM and the need for more inclusive investigative approaches in order to fully understand the pathogenesis of this disease. J. Cell. Physiol. 226: 2894–2900, 2011. © 2011 Wiley‐Liss, Inc. 相似文献