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41.
Background
Ypt/Rab GTPases and their GEF activators regulate intra-cellular trafficking in all eukaryotic cells. In S. cerivisiae, the modular TRAPP complex acts as a GEF for the Golgi gatekeepers: Ypt1 and the functional pair Ypt31/32. While TRAPPI, which acts in early Golgi, is conserved from fungi to animals, not much is known about TRAPPII, which acts in late Golgi and consists of TRAPPI plus three additional subunits. 相似文献42.
The ability of taxa to cross/hybridize is useful information for plant systematists and breeders. Crossability reflects reproductive isolation and the biological species concept stresses the need for reproductive isolation between species to maintain morphological distincness. For plant breeders knowledge on crossing ability facilitate selection of taxa for character improvement breeding. In this study, the crossing relationships and chromosome numbers within and among Ugandan species of Solanum sect. Solanum is studied by making 800 crosses involving 246 combinations. Less than half of these combinations were successful, producing F1 offspring. All studied accessions are self‐compatible and most accessions crossed readily with accessions of their own species. Interspecific crossings failed either to yield seeds, yielded F1 seeds that did not germinate, or resulted in F1s that did not have stainable pollen – implying a crossing barrier; or stainable pollen, but with chromosome numbers that indicated reproduction by apomixis. The results support the taxonomic treatment of Solanum based on classical, numerical and partly molecular evidences. The material studied represents eight Ugandan taxa: S. americanum, a diploid (2n = 2x = 24); five tetraploids (2n = 4x = 48) S. florulentum, S. memphiticum, S. tarderemotum, S. villosum ssp. villosum and S. villosum ssp. miniatum; and two hexaploids (2n = 6x = 72) S. scabrum subsp. scabrum and S. scabrum subsp. laevis. In addition to confirming the ploidy levels of the Ugandan accessions, the ploidy levels of S. florulentum, S. memphiticum and S. tarderemotum are reported for the first time. Non‐Ugandan material of Solanum sarrachoides was found to be diploid. Knowledge of the crossing behaviour and ploidy levels in Solanum will facilitate breeding for character improvement in these important species that are used commonly as food and/or medicine in eastern Africa. 相似文献
43.
Hoffmann TJ Kvale MN Hesselson SE Zhan Y Aquino C Cao Y Cawley S Chung E Connell S Eshragh J Ewing M Gollub J Henderson M Hubbell E Iribarren C Kaufman J Lao RZ Lu Y Ludwig D Mathauda GK McGuire W Mei G Miles S Purdy MM Quesenberry C Ranatunga D Rowell S Sadler M Shapero MH Shen L Shenoy TR Smethurst D Van den Eeden SK Walter L Wan E Wearley R Webster T Wen CC Weng L Whitmer RA Williams A Wong SC Zau C Finn A Schaefer C Kwok PY Risch N 《Genomics》2011,98(2):79-89
The success of genome-wide association studies has paralleled the development of efficient genotyping technologies. We describe the development of a next-generation microarray based on the new highly-efficient Affymetrix Axiom genotyping technology that we are using to genotype individuals of European ancestry from the Kaiser Permanente Research Program on Genes, Environment and Health (RPGEH). The array contains 674,517 SNPs, and provides excellent genome-wide as well as gene-based and candidate-SNP coverage. Coverage was calculated using an approach based on imputation and cross validation. Preliminary results for the first 80,301 saliva-derived DNA samples from the RPGEH demonstrate very high quality genotypes, with sample success rates above 94% and over 98% of successful samples having SNP call rates exceeding 98%. At steady state, we have produced 462 million genotypes per week for each Axiom system. The new array provides a valuable addition to the repertoire of tools for large scale genome-wide association studies. 相似文献
44.
45.
Chen EC Yagi S Kelly KR Mendoza SP Tarara RP Canfield DR Maninger N Rosenthal A Spinner A Bales KL Schnurr DP Lerche NW Chiu CY 《PLoS pathogens》2011,7(7):e1002155
Adenoviruses are DNA viruses that naturally infect many vertebrates, including humans and monkeys, and cause a wide range of clinical illnesses in humans. Infection from individual strains has conventionally been thought to be species-specific. Here we applied the Virochip, a pan-viral microarray, to identify a novel adenovirus (TMAdV, titi monkey adenovirus) as the cause of a deadly outbreak in a closed colony of New World monkeys (titi monkeys; Callicebus cupreus) at the California National Primate Research Center (CNPRC). Among 65 titi monkeys housed in a building, 23 (34%) developed upper respiratory symptoms that progressed to fulminant pneumonia and hepatitis, and 19 of 23 monkeys, or 83% of those infected, died or were humanely euthanized. Whole-genome sequencing of TMAdV revealed that this adenovirus is a new species and highly divergent, sharing <57% pairwise nucleotide identity with other adenoviruses. Cultivation of TMAdV was successful in a human A549 lung adenocarcinoma cell line, but not in primary or established monkey kidney cells. At the onset of the outbreak, the researcher in closest contact with the monkeys developed an acute respiratory illness, with symptoms persisting for 4 weeks, and had a convalescent serum sample seropositive for TMAdV. A clinically ill family member, despite having no contact with the CNPRC, also tested positive, and screening of a set of 81 random adult blood donors from the Western United States detected TMAdV-specific neutralizing antibodies in 2 individuals (2/81, or 2.5%). These findings raise the possibility of zoonotic infection by TMAdV and human-to-human transmission of the virus in the population. Given the unusually high case fatality rate from the outbreak (83%), it is unlikely that titi monkeys are the native host species for TMAdV, and the natural reservoir of the virus is still unknown. The discovery of TMAdV, a novel adenovirus with the capacity to infect both monkeys and humans, suggests that adenoviruses should be monitored closely as potential causes of cross-species outbreaks. 相似文献
46.
Roodenburg AJ Schlatmann A Dötsch-Klerk M Daamen R Dong J Guarro M Stergiou M Sayed N Ronoh E Jansen L Seidell JC 《PloS one》2011,6(2):e14721
Introduction
Nutrient profiling is defined as the science of categorising foods based on their nutrient composition. The Choices Programme is a nutrient profile system with criteria that determine whether foods are eligible to carry a “healthier option” stamp. The Daily Menu Method which has been developed to evaluate these criteria is described here. This method simulates the change in calculated nutrient intakes which would be the result of consumers changing their diets in favour of food products that comply with the criteria.Methods
Average intakes of energy, trans fatty acids (TFA), saturated fatty acids (SAFA), sodium, added sugar and fibre were derived from dietary intake studies and food consumption surveys of 7 countries: The Netherlands, Greece, Spain, the USA, Israel, China and South Africa. For each of the key nutrients, these average intakes were translated into three Typical Daily Menus per country. Average intakes based on these three menus were compared with average intakes from three Choices Daily Menus. To compose the Choices Menus, foods from the Typical Menus that did not comply with the Choices criteria were replaced with foods that did comply and are available on the market.Results
Comparison of intakes from the Choices Menus with the survey data showed that calculated intakes of energy, SAFA, TFA, sodium and added sugar were reduced. Fibre intakes were increased. The size of the effect differed per country.Conclusion
The Daily Menu Method is a useful means to predict the potential effects of nutrient profiles such as the Choices criteria, on daily nutrient intakes. The method can be applied internationally and confirms that the criteria of the Choices Programme are in line with the aim of the programme: to improve nutrient intakes in the direction of the recommendations. 相似文献47.
Stewart JM Gera L Chan DC York EJ Simkeviciene V Bunn PA Taraseviciene-Stewart L 《Peptides》2005,26(8):1288-1291
Lung and prostate cancers are major health problems worldwide. Treatments with standard chemotherapy agents are relatively ineffective. Combination chemotherapy gives better treatment than a single agent because the drugs can inhibit the cancer in different pathways, but new therapeutic agents are needed for the treatment of both tumor types. Bradykinin (BK) antagonists offer advantages of combination therapy in one compound. These promising multitargeted anti-cancer compounds selectively stimulate apoptosis in cancers and also inhibit both angiogenesis and matrix metalloprotease (MMP) action in treated lung and prostate tumors in nude mice. The highly potent, metabolism-resistant bradykinin antagonist peptide dimer, B-9870 [SUIM-(DArg-Arg-Pro-Hyp-Gly-Igl-Ser-DIgl-Oic-Arg)2] (SUIM=suberimidyl; Hyp=4-hydroxyproline; Igl=alpha-(2-indanyl)glycine; Oic=octahydroindole-2-carboxylic acid) and its non-peptide mimetic, BKM-570 [2,3,4,5,6-pentafluorocinnamoyl-(o-2,6-dichlorobenzyl)-L-tyrosine-N-(4-amino-2,2,6,6-tetramethylpiperidyl)amide] are superior to the widely used but toxic chemotherapeutic drugs cisplatin and taxotere. In certain combinations, they act synergistically with standard anti-cancer drugs. Due to its structure and biological activity, BKM-570 is an attractive lead compound for derivatization and evaluation for lung and prostate cancer drugs. 相似文献
48.
Savani ES Nunes VL Galati EA Castilho TM Araujo FS Ilha IM Camargo MC D'Auria SR Floeter-Winter LM 《Memórias do Instituto Oswaldo Cruz》2005,100(7):739-741
A natural case of co-infection by Leishmania and Trypanosoma is reported in a dog (Canis familiaris) in south- western state of Mato Grosso do Sul, Brazil. Both amastigote and trypomastigote forms were observed after Giemsa staining of cytological preparations of the dog's bone marrow aspirate. No parasite was detected using medium culture inoculation of the sample. DNA obtained from the bone marrow aspirate sample and from the blood buffy coat was submitted to polymerase chain reaction (PCR) with a set of rDNA-based primers S4/S12. The nucleotide sequence of the PCR product was identical to that of Trypanosoma (Trypanozoon) evansi. The S4/S12 PCR was then used as template in a nested-PCR using a specific Leishmania set S17/S18 as primers, to explain the amastigote forms. The nucleotide sequence of the new PCR product was identical to that of Leishmania (Leishmania) chagasi. This case, as far as we know, is the first report of a dog co-infected with these parasites, suggesting that besides L. (L.) chagasi, the natural transmission of T. (T.) evansi occurs in the area under study. 相似文献
49.
Silas?D.?ObukosiaEmail author Esther?Kimani Kimani?Waithaka Eunice?Mutitu P.?M.?Kimani 《In vitro cellular & developmental biology. Plant》2005,41(2):162-166
Summary The effects of growth regulators on culture response of different pyrethrum (Chrysanthemum cinerariaefolium Vis.) genotypes were investigated. In the genotype Sb/66/107, the presence of 2,4-dichorophenoxyacetic acid (2,4-D) at 2
mgl−1 promoted growth of callus, whereas benzyladenine and 1-naphthaleneacetic acid had no effect. Callus growth was also affected
by the 2,4-D, ranging from 0.5 mgl−1 for genotype Marwanga to 3.0 mgl−1 for Ks/75/336. Among the genotypes, shoots were regenerated from calluses of Sb/66/107, 4331, Marwanga, and MA/70/1013. 相似文献
50.
Inhibition of respiratory syncytial virus infection with intranasal siRNA nanoparticles targeting the viral NS1 gene 总被引:17,自引:0,他引:17
Zhang W Yang H Kong X Mohapatra S San Juan-Vergara H Hellermann G Behera S Singam R Lockey RF Mohapatra SS 《Nature medicine》2005,11(1):56-62
Respiratory syncytial virus (RSV) infection is one of the major causes of respiratory tract infection for which no vaccine or antiviral treatment is available. The RSV NS1 protein seems to antagonize the host interferon (IFN) response; however, its mechanism is unknown. Here, we used a plasmid-borne small interfering RNA targeting the NS1 gene (siNS1) to examine the role of NS1 in modulating RSV infection. RSV replication was reduced in A549 cells, but not IFN-deficient Vero cells, transfected with siNS1. siNS1 induced upregulated expression of IFN-beta and IFN-inducible genes in A549 cells. siNS1-transfected human dendritic cells, upon RSV infection, produced elevated type-1 IFN and induced differentiation of naive CD4+ T cells to T helper type 1 (TH1) cells. Mice treated intranasally with siNS1 nanoparticles before or after infection with RSV showed substantially decreased virus titers in the lung and decreased inflammation and airway reactivity compared to controls. Thus, siNS1 nanoparticles may provide an effective inhibition of RSV infection in humans. 相似文献