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1.
Mariann Thymann Bernadette Hoste Wolfgang Scheffrahn Jacques Constans Hartwig Cleve 《Human genetics》1985,69(3):224-227
Summary The proteins of three anodal Gc1 variants, Gc 1A16, 1A11, and 1A17, are characterized by the most acidic isoelectric points observed so far among the different Gc mutants. Stepwise removal of N-acetylneuraminic acid (NANA) by treatment with neuraminidase was performed to estimate the degree of sialilation of these Gc variants. The results indicate that both proteins, the anodal and the cathodal component of these Gc 1 mutants, carry sialic acid residues. This observation is remarkable in so far as usually only the anodal component of the Gc 1 protein contains NANA and only a single residue. From the experiments carried out it can be deduced that Gc 1A16 has two NANA residues in the anodal and one NANA residue in the cathodal component. Gc 1A16 was found in four members of three generations in a Danish family; the variant segregated as a Mendelian trait. More difficult to interprete are the results obtained with the variants Gc 1A11 and Gc 1A17. Gc 1A11 probably has three NANA residues in the anodal and two NANA residues in the cathodal component. Gc 1A11 has been observed in two mother-child pairs and is presumably also a simple genetic trait. Gc 1A17 has also several NANA residues in both Gc proteins; it is suggested that the anodal component has either three or four NANA residues and the cathodal component either two or three NANA residues. Family information on this variant is not yet available. 相似文献
2.
Simone Prospero Malve Heinz Eva Augustiny Ying-Yu Chen Juanita Engelbrecht Marina Fonti Aliona Hoste Beat Ruffner Romina Sigrist Noelani van den Berg Patrick Fonti 《Environmental microbiology》2023,25(11):2250-2265
Emerging diseases caused by both native and exotic pathogens represent a main threat to forest ecosystems worldwide. The two invasive soilborne pathogens Phytophthora cinnamomi and Phytophthora × cambivora are the causal agents of ink disease, which has been threatening Castanea sativa in Europe for several centuries and seems to be re-emerging in recent years. Here, we investigated the distribution, causal agents, and infection dynamics of ink disease in southern Switzerland. A total of 25 outbreaks were identified, 19 with only P. cinnamomi, 5 with only P. × cambivora, and 1 with both species. Dendrochronological analyses showed that the disease emerged in the last 20–30 years. Infected trees either died rapidly within 5–15 years post-infection or showed a prolonged state of general decline until death. Based on a generalized linear model, the local risk of occurrence of ink disease was increased by an S-SE aspect of the chestnut stand, the presence of a pure chestnut stand, management activities, the proximity of roads and buildings, and increasing annual mean temperature and precipitation. The genetic structure of the local P. cinnamomi population suggests independent introductions and local spread of the pathogen. 相似文献
3.
An anaerobic modification of conventional polyscrylamide-gel electrophoretic equipment is described. The modified apparatus has been applied to the separation of Azotobacter vinelandii nitrogenase components and should prove useful in the analysis of other O2-sensitive proteins. Electrophoresis in reducing gels can be followed with a dithionite-resistant tracking dye, potassium gualazulene-1-sulfonate. 相似文献
4.
The feasibility of infecting laboratory rabbits experimentally with the ovine nematode Nematodirus spathiger was examined. Eight-week-old rabbits were dosed either with 5000 or with 17,000 third-stage larvae and killed on days 10, 21 or 42 post-infection. With the lower dose, 20 to 40% of the inoculum were recovered at necropsy. Similar values were observed with the 17,000 dose on days 10 and 21 post-infection, but on day 42 the worm population was residual (0.6%). With both dose levels, during the course of infection, the worm populations were mainly composed of fourth-stage larvae and worm egg excretion was low. N. spathiger mainly inhabited the proximal jejunum. The results were compared with N. spathiger infection in sheep to assess the usefulness of the rabbit as an experimental model for Nematodirus infection. 相似文献
5.
Bruno Hoste Lieve Luyten Ilse Claeys Elke Clynen Mazibur M. Rahman Arnold De Loof Michael Breuer 《Entomologia Experimentalis et Applicata》2002,104(2-3):281-288
In order to unravel the physiological, endocrine, and behavioral differences between gregarious and solitarious forms of the desert locust, Schistocerca gregaria (Forsk.) (Orthoptera, Acrididae), a constant supply of rather large numbers of solitary individuals has to be guaranteed. This represents a bottleneck, mainly because of the intensity of the labor involved and limited laboratory accommodation. The method we describe here substantially reduces the space and manpower needed. The survival rate we obtained in the solitarised population was relatively high, reaching about 55%. The optimal rearing temperature proved to be 32–36 °C. Cabbage leaves and oat flakes sufficed for feeding all year round. Special racks have been designed that enable high density stacking and easy handling. The solitarisation process was monitored over ten consecutive generations. Changes in morphometrics, eye stripes, color, and behavior were recorded, of which only morphometrics, temperature related development, and mortality are discussed. A shift towards the solitarious phase was recorded, with clear differences between gregarious, 1st generation and 7th to 10th generation solitarious locusts. 相似文献
6.
7.
Maria C Romay Mark J Millard Jeffrey C Glaubitz Jason A Peiffer Kelly L Swarts Terry M Casstevens Robert J Elshire Charlotte B Acharya Sharon E Mitchell Sherry A Flint-Garcia Michael D McMullen James B Holland Edward S Buckler Candice A Gardner 《Genome biology》2013,14(6):R55
Background
Genotyping by sequencing, a new low-cost, high-throughput sequencing technology was used to genotype 2,815 maize inbred accessions, preserved mostly at the National Plant Germplasm System in the USA. The collection includes inbred lines from breeding programs all over the world.Results
The method produced 681,257 single-nucleotide polymorphism (SNP) markers distributed across the entire genome, with the ability to detect rare alleles at high confidence levels. More than half of the SNPs in the collection are rare. Although most rare alleles have been incorporated into public temperate breeding programs, only a modest amount of the available diversity is present in the commercial germplasm. Analysis of genetic distances shows population stratification, including a small number of large clusters centered on key lines. Nevertheless, an average fixation index of 0.06 indicates moderate differentiation between the three major maize subpopulations. Linkage disequilibrium (LD) decays very rapidly, but the extent of LD is highly dependent on the particular group of germplasm and region of the genome. The utility of these data for performing genome-wide association studies was tested with two simply inherited traits and one complex trait. We identified trait associations at SNPs very close to known candidate genes for kernel color, sweet corn, and flowering time; however, results suggest that more SNPs are needed to better explore the genetic architecture of complex traits.Conclusions
The genotypic information described here allows this publicly available panel to be exploited by researchers facing the challenges of sustainable agriculture through better knowledge of the nature of genetic diversity. 相似文献8.
Constantin Jansen Natalia de Leon Nick Lauter Candice Hirsch Leah Ruff Thomas Lübberstedt 《Bioenergy Research》2013,6(3):903-916
Expected future cellulosic ethanol production increases the demand for biomass in the US Corn Belt. With low nutritious value, low nitrogen content, and compact biomass, maize cobs can provide a significant amount of cellulosic materials. The value of maize cobs depends on cob architecture, chemical composition, and their relation to grain yield as primary trait. Eight traits including cob volume, fractional diameters, length, weight, tissue density, and grain yield have been analyzed in this quantitative trait locus (QTL) mapping experiment to evaluate their inheritance and inter-relations. One hundred eighty-four recombinant inbred lines of the intermated B73?×?Mo17 (IBM) Syn 4 population were evaluated from an experiment carried out at three locations and analyzed using genotypic information of 1,339 public SNP markers. QTL detection was performed using (1) comparison-wise thresholds with reselection of cofactors (α?=?0.001) and (2) empirical logarithm of odds score thresholds (P?=?0.05). Several QTL with small genetic effects (R 2?=?2.9–13.4 %) were found, suggesting a complex quantitative inheritance of all traits. Increased cob tissue density was found to add value to the residual without a commensurate negative impact on grain yield and therefore enables for simultaneous selection for cob biomass and grain yield. 相似文献
9.
Isabel A. Cáceres Mariana Arcaya Eugene Declercq Candice M. Belanoff Vanitha Janakiraman Bruce Cohen Jeffrey Ecker Lauren A. Smith S. V. Subramanian 《PloS one》2013,8(3)
Objective
We examined the extent to which differences in hospital-level cesarean delivery rates in Massachusetts were attributable to hospital-level, rather than maternal, characteristics.Methods
Birth certificate and maternal in-patient hospital discharge records for 2004–06 in Massachusetts were linked. The study population was nulliparous, term, singleton, and vertex births (NTSV) (n = 80,371) in 49 hospitals. Covariates included mother''s age, race/ethnicity, education, infant birth weight, gestational age, labor induction (yes/no), hospital shift at time of birth, and preexisting health conditions. We estimated multilevel logistic regression models to assess the likelihood of a cesarean deliveryResults
Overall, among women with NTSV births, 26.5% births were cesarean, with a range of 14% to 38.3% across hospitals. In unadjusted models, the between-hospital variance was 0.103 (SE 0.022); adjusting for demographic, socioeconomic and preexisting medical conditions did not reduce any hospital-level variation 0.108 (SE 0.023).Conclusion
Even after adjusting for both socio-demographic and clinical factors, the chance of a cesarean delivery for NTSV pregnancies varied according to hospital, suggesting the importance of hospital practices and culture in determining a hospital''s cesarean rate. 相似文献10.
Luqiao?Wang Hangfei?Fu Gayani?Nanayakkara Yafeng?Li Ying?Shao Candice?Johnson Jiali?Cheng William?Y.?Yang Fan?Yang Muriel?Lavallee Yanjie?Xu Xiaoshu?Cheng Hang?Xi Jonathan?Yi Jun?Yu Eric?T.?Choi Hong?Wang Xiaofeng?Yang