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31.
Paul S Marley Aboubacar Toure Jay Shebayan DA Aba AO Toure AG Diallo 《Archives Of Phytopathology And Plant Protection》2013,46(1):29-34
Fourteen elite sorghum lines were evaluated for their resistance to Striga hermonthica at three locations in Nigeria and Mali. Results showed that many of the lines especially MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64 (Keninkédié) and the check SRN 39 remained resistant to Striga in all locations with low emerged Striga counts, while SAMSORG 14 had the highest Striga infestation in all locations. Considerable variation in reaction to Striga infestation was observed on Séguètana, 97-SB-F5DT-63 (Wasa), 97-SB-F5DT-65, CMDT 38, CMDT 39 and CMDT 45 which were susceptible to Striga at Samaru, Nigeria but were resistant to Striga at both locations in Mali. Based on low Striga resistance and high grain yield, lines MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64, 97-SB-F5DT-65, CMDT 39 and SAMSORT 14 have been nominated for wider evaluation across more West African countries. 相似文献
32.
Yongqi Deng Zhiwei Yang Gerald W. Shipps Sie-Mun Lo Robert West Joyce Hwa Shuqin Zheng Constance Farley Jean Lachowicz Margaret van Heek Alan S. Bass Dinesh P. Sinha Craig R. Mahon Mark E. Cartwright 《Bioorganic & medicinal chemistry letters》2013,23(3):791-796
Inhibitors based on a benzo-fused spirocyclic oxazepine scaffold were discovered for stearoyl-coenzyme A (CoA) desaturase 1 (SCD1) and subsequently optimized to potent compounds with favorable pharmacokinetic profiles and in vivo efficacy in reducing the desaturation index in a mouse model. Initial optimization revealed potency preferences for the oxazepine core and benzylic positions, while substituents on the piperidine portions were more tolerant and allowed for tuning of potency and PK properties. After preparation and testing of a range of functional groups on the piperidine nitrogen, three classes of analogs were identified with single digit nanomolar potency: glycine amides, heterocycle-linked amides, and thiazoles. Responding to concerns about target localization and potential mechanism-based side effects, an initial effort was also made to improve liver concentration in an available rat PK model. An advanced compound 17m with a 5-carboxy-2-thiazole substructure appended to the spirocyclic piperidine scaffold was developed which satisfied the in vitro and in vivo requirements for more detailed studies. 相似文献
33.
ABSTRACT The vocal repertoire of Amazona amazonica during its breeding season has been recorded from wild individuals in Santa Bárbara do Pará, Pará State, Brazil. At individual nests, we continuously recorded vocalizations and behaviour for four hours in the early morning and three hours in the late afternoon, three times a week throughout the breeding season. We identified nine vocalizations that we classified in three behavioural categories: (1) Flight call—emitted when parrots arrive in the nest area; (2) Perched contact calls—two different vocalizations, one of them related to feeding, were emitted when the pair was perched in the nest area and interacted socially between themselves or with other individuals; (3) Aggressive calls—emitted when birds were in a dangerous situation, i.e. alarm (three types of calls), agonistic contact and distress calls (two types of call). The Orange-winged Parrot is a highly social species and the complexity of its social interactions is reflected in the diversity of its vocal repertoire. 相似文献
34.
Emma C. Wall Katharine Cartwright Matthew Scarborough Katherine M. Ajdukiewicz Patrick Goodson James Mwambene Eduard E. Zijlstra Stephen B. Gordon Neil French Brian Faragher Robert S. Heyderman David G. Lalloo 《PloS one》2013,8(7)
Mortality from bacterial meningitis in African adults is significantly higher than those in better resourced settings and adjunctive therapeutic interventions such as dexamethasone and glycerol have been shown to be ineffective. We conducted a study analysing data from clinical trials of bacterial meningitis in Blantyre, Malawi to investigate the clinical parameters associated with this high mortality.
Methods
We searched for all clinical trials undertaken in Blantyre investigating bacterial meningitis from 1990 to the current time and combined the data from all included trial datasets into one database. We used logistic regression to relate individual clinical parameters to mortality. Adults with community acquired bacterial meningitis were included if the CSF culture isolate was consistent with meningitis or if the CSF white cell count was >100 cells/mm3 (>50% neutrophils) in HIV negative participants and >5 cells/mm3 in HIV positive participants. Outcome was measured by mortality at discharge from hospital (after 10 days of antibiotic therapy) and community follow up (day 40).Results
Seven hundred and fifteen episodes of bacterial meningitis were evaluated. The mortality rate was 45% at day 10 and 54% at day 40. The most common pathogens were S.pneumoniae (84% of positive CSF isolates) and N.meningitidis (4%). 607/694 (87%) participants tested were HIV antibody positive. Treatment delays within the hospital system were marked. The median presenting GCS was 12/15, 17% had GCS<8 and 44.9% had a seizure during the illness. Coma, seizures, tachycardia and anaemia were all significantly associated with mortality on multivariate analysis. HIV status and pneumococcal culture positivity in the CSF were not associated with mortality. Adults with community acquired bacterial meningitis in Malawi present with a severe clinical phenotype. Predictors of high mortality are different to those seen in Western settings. Optimising in-hospital care and minimising treatment delays presents an opportunity to improve outcomes considerably. 相似文献35.
目的:探讨初治、年轻、中高/高危弥漫大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的临床特征、治疗措施及预后影响因素。方法:回顾性分析2006年1月至2014年5月军事医学科学院附属医院淋巴瘤科收治的年龄≤60岁、年龄调整的国际预后指数(aa IPI)评分≥2分的初治DLBCL病例,进行疗效及预后相关因素的分析。结果:共收集到资料完整的DLBCL病例120例,中位随访28(4-106)个月,3年PFS率53.25%,OS率61.52%。单因素分析结果显示B症状、治疗方案及近期疗效、自体移植对无进展生存(PFS)及总体生存(OS)率的影响有统计学意义。多因素分析结果显示治疗方案、自体造血干细胞移植是影响PFS、OS率的独立影响因素。结论:年轻、中高/高危DLBCL具有高度异质性,病理细胞来源、Ki-67等在本组病例中未见显著预后意义,有待临床进一步探索。 相似文献
36.
Ellen P. M. van Loon Robert Little Sukhpal Prehar René J. M. Bindels Elizabeth J. Cartwright Joost G. J. Hoenderop 《PloS one》2016,11(4)
Calcium (Ca2+) is vital for multiple processes in the body, and maintenance of the electrolyte concentration is required for everyday physiological function. In the kidney, and more specifically, in the late distal convoluted tubule and connecting tubule, the fine-tuning of Ca2+ reabsorption from the pro-urine takes place. Here, Ca2+ enters the epithelial cell via the transient receptor potential vanilloid receptor type 5 (TRPV5) channel, diffuses to the basolateral side bound to calbindin-D28k and is extruded to the blood compartment via the Na+/Ca2+ exchanger 1 (NCX1) and the plasma membrane Ca2+ ATPase (PMCA). Traditionally, PMCA1 was considered to be the primary Ca2+ pump in this process. However, in recent studies TRPV5-expressing tubules were shown to highly express PMCA4. Therefore, PMCA4 may have a predominant role in renal Ca2+ handling. This study aimed to elucidate the role of PMCA4 in Ca2+ homeostasis by characterizing the Ca2+ balance, and renal and duodenal Ca2+-related gene expression in PMCA4 knockout mice. The daily water intake of PMCA4 knockout mice was significantly lower compared to wild type littermates. There was no significant difference in serum Ca2+ level or urinary Ca2+ excretion between groups. In addition, renal and duodenal mRNA expression levels of Ca2+-related genes, including TRPV5, TRPV6, calbindin-D28k, calbindin-D9k, NCX1 and PMCA1 were similar in wild type and knockout mice. Serum FGF23 levels were significantly increased in PMCA4 knockout mice. In conclusion, PMCA4 has no discernible role in normal renal Ca2+ handling as no urinary Ca2+ wasting was observed. Further investigation of the exact role of PMCA4 in the distal convoluted tubule and connecting tubule is required. 相似文献
37.
Badgers prefer cattle pasture but avoid cattle: implications for bovine tuberculosis control
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Rosie Woodroffe Christl A. Donnelly Cally Ham Seth Y. B. Jackson Kelly Moyes Kayna Chapman Naomi G. Stratton Samantha J. Cartwright 《Ecology letters》2016,19(10):1201-1208
Effective management of infectious disease relies upon understanding mechanisms of pathogen transmission. In particular, while models of disease dynamics usually assume transmission through direct contact, transmission through environmental contamination can cause different dynamics. We used Global Positioning System (GPS) collars and proximity‐sensing contact‐collars to explore opportunities for transmission of Mycobacterium bovis [causal agent of bovine tuberculosis] between cattle and badgers (Meles meles). Cattle pasture was badgers’ most preferred habitat. Nevertheless, although collared cattle spent 2914 collar‐nights in the home ranges of contact‐collared badgers, and 5380 collar‐nights in the home ranges of GPS‐collared badgers, we detected no direct contacts between the two species. Simultaneous GPS‐tracking revealed that badgers preferred land > 50 m from cattle. Very infrequent direct contact indicates that badger‐to‐cattle and cattle‐to‐badger M. bovis transmission may typically occur through contamination of the two species’ shared environment. This information should help to inform tuberculosis control by guiding both modelling and farm management. 相似文献
38.
39.
A dense single-nucleotide polymorphism-based genetic linkage map of grapevine (Vitis vinifera L.) anchoring Pinot Noir bacterial artificial chromosome contigs 总被引:1,自引:0,他引:1
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Troggio M Malacarne G Coppola G Segala C Cartwright DA Pindo M Stefanini M Mank R Moroldo M Morgante M Grando MS Velasco R 《Genetics》2007,176(4):2637-2650
The construction of a dense genetic map for Vitis vinifera and its anchoring to a BAC-based physical map is described: it includes 994 loci mapped onto 19 linkage groups, corresponding to the basic chromosome number of Vitis. Spanning 1245 cM with an average distance of 1.3 cM between adjacent markers, the map was generated from the segregation of 483 single-nucleotide polymorphism (SNP)-based genetic markers, 132 simple sequence repeats (SSRs), and 379 AFLP markers in a mapping population of 94 F(1) individuals derived from a V. vinifera cross of the cultivars Syrah and Pinot Noir. Of these markers, 623 were anchored to 367 contigs that are included in a physical map produced from the same clone of Pinot Noir and covering 352 Mbp. On the basis of contigs containing two or more genetically mapped markers, region-dependent estimations of physical and recombinational distances are presented. The markers used in this study include 118 SSRs common to an integrated map derived from five segregating populations of V. vinifera. The positions of these SSR markers in the two maps are conserved across all Vitis linkage groups. The addition of SNP-based markers introduces polymorphisms that are easy to database, are useful for evolutionary studies, and significantly increase the density of the map. The map provides the most comprehensive view of the Vitis genome reported to date and will be relevant for future studies on structural and functional genomics and genetic improvement. 相似文献
40.
Understanding the nature and timing of metazoan origins is oneof the most important, yet elusive, questions in evolutionarybiology. Fossil data provide the most tangible evidence forthe origin of early animal lineages, although additional evidencefrom molecular phylogenetics, molecular clock studies, and developmenthas contributed to our current understanding. We review severallines of evidence to explore the nature and timing of earlymetazoan evolution and discuss how these data, when consideredtogether, provide a more cohesive picture of the origin of animaldiversity. We discuss how trace fossils and biomarkers providecompelling evidence for the origins of Bilateria and siliceoussponges. Using a molecular phylogenetic framework for metazoans,we discuss how fossils can be used to date the origin of clades.We use these fossil dates to perform a relaxed molecular clockanalysis for estimating dates of nodes when no fossils are available.We also discuss current data from developmental biology thatsuggest that early metazoans possessed a sophisticated moleculartoolkit for building complex body plans. We conclude that thebest evidence for the origin of major metazoan lineages liesin the careful interpretation of the fossil record and thatthese data, when considered with phylogenetic and developmentalevidence, support the notion that the Cambrian radiation isa real phenomenon that marks a critically important time inthe history of life. 相似文献