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131.
132.
The mosquito Aedes japonicus japonicus, originally restricted to temperate East Asia, is now widespread in North America and more recently has become established in Europe. To ascertain the putative number of separate introductions to Europe and examine patterns of expansion we analyzed the genetic makeup of Ae. j. japonicus populations from five cemeteries in North Rhine-Westphalia and Rhineland-Palatinate, two western German federal states, as well as of specimens from populations in Belgium, Switzerland, and Austria/Slovenia. To do so, we genotyped individual specimens at seven pre-existing polymorphic microsatellite loci and sequenced part of the nad4 mitochondrial locus. We found evidence of two different genotypic signatures associated with different nad4 mitochondrial haplotypes, indicating at least two genetically differentiated populations of Ae. j. japonicus in Europe (i.e. two distinct genotypes). Belgian, Swiss, and Austrian/Slovenian populations all share the same genotypic signature although they have become differentiated since isolation. Contrary to expectations, the German Ae. j. japonicus are not closely related to those in Belgium which are geographically nearest but are also highly inbred. German populations have a unique genotype but also evidence of mixing between the two genotypes. Also unexpectedly, the populations closest to the center of the German infestation had the highest levels of admixture indicating that separate introductions did not expand and merge but instead their expansion was driven by punctuated human-mediated transport. Critically, the resulting admixed populations have higher genetic diversity and appear invasive as indicated by their increased abundance and recent spread across western Germany. 相似文献
133.
Andrea M. Weckman Andrea L. Conroy Mwayiwawo Madanitsa Bruno Gnaneswaran Chloe R. McDonald Linda Kalilani-Phiri Jaya Chandna Doreen Ali Victor Mwapasa Carole Khairallah Kyaw Lay Thwai Steven R. Meshnick Steve M. Taylor Feiko O. ter Kuile Kevin C. Kain Melissa Gladstone 《PLoS medicine》2021,18(9)
BackgroundAnnually 125 million pregnancies are at risk of malaria infection. However, the impact of exposure to malaria in pregnancy on neurodevelopment in children is not well understood. We hypothesized that malaria in pregnancy and associated maternal immune activation result in neurodevelopmental delay in exposed offspring.Methods and findingsBetween April 2014 and April 2015, we followed 421 Malawian mother–baby dyads (median [IQR] maternal age: 21 [19, 28] years) who were previously enrolled (median [IQR] gestational age at enrollment: 19.7 [17.9, 22.1] weeks) in a randomized controlled malaria prevention trial with 5 or 6 scheduled assessments of antenatal malaria infection by PCR. Children were evaluated at 12, 18, and/or 24 months of age with cognitive tests previously validated in Malawi: the Malawi Developmental Assessment Tool (MDAT) and the MacArthur–Bates Communicative Development Inventories (MCAB-CDI). We assessed the impact of antenatal malaria (n [%] positive: 240 [57.3]), placental malaria (n [%] positive: 112 [29.6]), and maternal immune activation on neurocognitive development in children. Linear mixed-effects analysis showed that children exposed to antenatal malaria between 33 and 37 weeks gestation had delayed language development across the 2-year follow-up, as measured by MCAB-CDI (adjusted beta estimate [95% CI], −7.53 [−13.04, −2.02], p = 0.008). Maternal immune activation, characterized by increased maternal sTNFRII concentration, between 33 and 37 weeks was associated with lower MCAB-CDI language score (adjusted beta estimate [95% CI], −8.57 [−13.09, −4.06], p < 0.001). Main limitations of this study include a relatively short length of follow-up and a potential for residual confounding that is characteristic of observational studies.ConclusionsThis mother–baby cohort presents evidence of a relationship between malaria in pregnancy and neurodevelopmental delay in offspring. Malaria in pregnancy may be a modifiable risk factor for neurodevelopmental injury independent of birth weight or prematurity. Successful interventions to prevent malaria during pregnancy may reduce the risk of neurocognitive delay in children.Andrea Weckman and co-workers study associations between children’s neurodevelopmental outcomes and malaria in pregnancy. 相似文献
134.
Doreen Ware Pankaj Jaiswal Junjian Ni Xiaokang Pan Kuan Chang Kenneth Clark Leonid Teytelman Steve Schmidt Wei Zhao Samuel Cartinhour Susan McCouch Lincoln Stein 《Nucleic acids research》2002,30(1):103-105
Gramene (http://www.gramene.org) is a comparative genome mapping database for grasses and a community resource for rice. Rice, in addition to being an economically important crop, is also a model monocot for understanding other agronomically important grass genomes. Gramene replaces the existing AceDB database ‘RiceGenes’ with a relational database based on Oracle. Gramene provides curated and integrative information about maps, sequence, genes, genetic markers, mutants, QTLs, controlled vocabularies and publications. Its aims are to use the rice genetic, physical and sequence maps as fundamental organizing units, to provide a common denominator for moving from one crop grass to another and is to serve as a portal for interconnecting with other web-based crop grass resources. This paper describes the initial steps we have taken towards realizing these goals. 相似文献
135.
Richter D Sermann H Jäckel B Büttner CB 《Communications in agricultural and applied biological sciences》2007,72(3):399-410
Strains from Paecilomyces fumosoroseus, Lecanicillium muscarium, Metarhizium anisopliae and Beauveria bassiana were examined in standardized Biotest to control the horse-chestnut leaf miner (Cameraria ohridella) in her pupal stage in winter. The fungi were pathogenic against the hibernating pupae of Cameraria ohridella at dose of 1.9 x 10(7) conidia/ml. They were aggressive, led to infection, death and mouldiness of naked pupae. Even at low temperature of 5 degrees C and 12 degrees C. L. muscarium strain V24 showed the highest pathogenicity after 4 weeks against this host, close followed by P. fumosoroseus strain P6. M. anisopliae strain 72 and 8. bassiana strain B412 were also pathogen but after a long-time period. Experiments gave information for general susceptibility of naked pupae of C. ohridella under low temperatures against entomopathogenic fungi. In further examinations it has to be tested, whether fungi can infected, when the pupae stay in their natural surroundings, the pupal cell in the leaf. 相似文献
136.
Lambros MP Parsa C Mulamalla H Orlando R Lau B Huang Y Pon D Chow M 《Biochemical and biophysical research communications》2011,411(1):102-106
Mature adipocytes are excellent candidates to influence tumor behavior through heterotypic signaling processes since these cells produce hormones, growth factors, cytokines and other molecules, a heterogeneous group of molecules named adipokines. Using a 2D coculture system, we demonstrate that breast tumor cells previously co-cultivated with mature adipocytes exhibit radioresistance and an earlier and higher increase in the effector kinase Chk1, a phenotype that was associated with decreased cell death as compared to tumor cells grown alone. Interestingly, the adipocytes-induced tumor changes taking place during the coculture time preceding the exposure to IR were sufficient to confer the radioresistant effect. Notorious among the changes brought by adipocytes was the significant increase of IL-6 expression in tumor cells, whose activity may well account for the observed tumor cell protection from IR toxicity. Indeed, our data confirmed the protective role of this cytokine as tumor cells incubated after irradiation with recombinant IL-6 exhibit an increased in Chk1 phosphorylation and a radioresistant phenotype, thus far recapitulating the effects observed in the presence of adipocytes. Our current study sheds light on a new role of tumor-surrounding adipocytes in fostering a radioresistant phenotype in breast tumors, a finding that might have important clinical implications in obese patients that frequently exhibit aggressive diseases. 相似文献
137.
Linda H Münger Mar Garcia-Aloy Rosa Vázquez-Fresno Doreen Gille Albert Remus R Rosana Anna Passerini María-Trinidad Soria-Florido Grégory Pimentel Tanvir Sajed David S Wishart Cristina Andres Lacueva Guy Vergères Giulia Praticò 《Genes & nutrition》2018,13(1):26
Dairy and egg products constitute an important part of Western diets as they represent an excellent source of high-quality proteins, vitamins, minerals and fats. Dairy and egg products are highly diverse and their associations with a range of nutritional and health outcomes are therefore heterogeneous. Such associations are also often weak or debated due to the difficulty in establishing correct assessments of dietary intake. Therefore, in order to better characterize associations between the consumption of these foods and health outcomes, it is important to identify reliable biomarkers of their intake. Biomarkers of food intake (BFIs) provide an accurate measure of intake, which is independent of the memory and sincerity of the subjects as well as of their knowledge about the consumed foods. We have, therefore, conducted a systematic search of the scientific literature to evaluate the current status of potential BFIs for dairy products and BFIs for egg products commonly consumed in Europe. Strikingly, only a limited number of compounds have been reported as markers for the intake of these products and none of them have been sufficiently validated. A series of challenges hinders the identification and validation of BFI for dairy and egg products, in particular, the heterogeneous composition of these foods and the lack of specificity of the markers identified so far. Further studies are, therefore, necessary to validate these compounds and to discover new candidate BFIs. Untargeted metabolomic strategies may allow the identification of novel biomarkers, which, when taken separately or in combination, could be used to assess the intake of dairy and egg products. 相似文献
138.
Bon Marie-Claude Bonal Damien Goh Doreen K. Monteuuis Olivier 《Plant Cell, Tissue and Organ Culture》1998,53(3):171-177
The influence of five different macronutrient formulations and various growth regulators on micropropagation of single node
explants from Acacia mangium and Paraserianthes falcataria seedlings was examined after 4 weeks and 8 weeks in vitro. The
experiment was repeated 4 months later. On media lacking growth regulators, growth and development were significantly influenced
by the different macronutrient solutions tested, although morphogenic responses could vary according to the species. For instance,
P. falcataria displayed a greater ability for adventitious rooting than A. mangium. Overall, Knop macronutrient solution induced
the weakest responses. Explant responsiveness was significantly influenced by the addition of 2.2 or 4.4 μM 6-benzyladenine
combined with either 1.4 or 2.3 μM kinetin, 1.5 or 2.5 μM indolebutyric acid or 1.6 or 2.7 μM naphthaleneacetic acid. The
various combinations of growth regulators tested were shown to inhibit the rooting ability of the explants, while stimulating
the production of basal shoots for both species, and of axillary shoots only for A. mangium. In such experimental conditions,
A. mangium displayed overall a greater potential for micropropagation than P. falcataria.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
139.
X-ray irradiation influences metastatic properties of tumor cells and, moreover, metastasis and cellular motility can be modified by members of the Eph receptor/ephrin family of receptor tyrosine kinases. We hypothesized that irradiation-induced changes in cellular properties relevant for metastasis in melanoma cells could be mediated by Eph receptor/ephrin signaling. In this pilot study, we analyzed one pre-metastatic (Mel-Juso) and three metastatic human melanoma (Mel-Juso-L3, A375, and A2058) cells lines and predominantly found anti-metastatic effects of X-ray irradiation with impaired cell growth, clonal growth and motility. Additionally, we observed an irradiation-induced increase in adhesion paralleled by a decrease in migration in Mel-Juso and Mel-Juso-L3 cells and, in part, also in A375 cells. We further demonstrate a decrease of EphA2 both in expression and activity at 7 d after irradiation paralleled by an upregulation of EphA3. Analyzing downstream signaling after irradiation, we detected decreased Src kinase phosphorylation, but unchanged focal adhesion kinase (FAK) phosphorylation, indicating, in part, irradiation-induced downregulation of signaling via the EphA2-Src-FAK axis in melanoma cells. However, to which extent this finding contributes to the modification of metastasis-relevant cellular properties remains to be elucidated. 相似文献
140.
Grace G. Y. Lim Doreen S. K. Chua Adeline H. Basil Hui-Ying Chan Chou Chai Thiruma Arumugam Kah-Leong Lim 《The Journal of biological chemistry》2015,290(27):16882-16893
The potential cellular function of the 53-kDa cytosolic form of PINK1 (PINK1-53) is often overlooked because of its rapid degradation by the proteasome upon its production. Although a number of recent studies have suggested various roles for PINK1-53, how this labile PINK1 species attains an adequate expression level to fulfil these roles remains unclear. Here we demonstrated that PINK1-53 is stabilized in the presence of enhanced Lys-63-linked ubiquitination and identified TRAF6-related NF-κB activation as a novel pathway involved in this. We further showed that a mimetic of PINK1-53 promotes mitophagy but, curiously, in apparently healthy mitochondria. We speculate that this “non-selective” form of mitophagy may potentially help to counteract the build-up of reactive oxygen species in cells undergoing oxidative stress and, as such, represent a cytoprotective response. 相似文献