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1.
Dr AR Holmes RD Cannon HF Jenkinson 《Journal of industrial microbiology & biotechnology》1995,15(3):208-213
The yeastCandida albicans coaggregates with a variety of streptococcal species, an interaction that may promote oral colonization by yeast cells.C. albicans andCandida tropicalis are the yeasts most frequently isolated from the human oral cavity and our data demonstrate that both these species bind toStreptococcus gordonii NCTC 7869 while two otherCandida species (Candida krusei andCandida kefyr) do not. Adherence ofC. albicans was greatest when the yeast had been grown at 30° C to mid-exponential growth phase. For 21 strains ofC. albicans there was a positive correlation between the ability to adhere toS. gordonii and adherence to experimental salivary pellicle. Whole saliva either stimulated or slightly inhibited adherence ofC. albicans toS. gordonii depending on the streptococcal growth conditions. The results suggest that the major salivary adhesins and coaggregation adhesins ofC. albicans are co-expressed. 相似文献
2.
Willmar L. Leiser Marcus O. Olatoye H. Frederick W. Rattunde Günter Neumann Eva Weltzien Bettina I. G. Haussmann 《Plant and Soil》2016,409(1-2):51-64
Background and aims
Herbaspirillum seropedicae (Hs) Z67 a diazotrophic endophyte was genetically engineered for secretion of 2-keto-D-gluconic acid by heterologous expression of genes for pqq synthesis and gluconate dehydrogenase to study its beneficial effect on plants.Methods
Two plasmids, pJNK5, containing a 5.1 Kb pqq gene cluster of Acinetobacter calcoaceticus and pJNK6, carrying in addition the Pseudomonas putida KT2440 gluconate dehydrogenase (gad) operon were constructed in pUCPM18Gmr under Plac promoter. H. seropedicae Z67 transformants were monitored for P and K solubilization, cadmium (Cd) tolerance and rice growth promotion.Results
Hs (pJNK5) secreted 23.5 mM gluconic acid and Hs (pJNK6) secreted 3.79 mM gluconic acid and 15.8 mM 2-ketogluconic acid respectively. Under aerobic conditions, Hs (pJNK5) and Hs (pJNK6) solubilized 239.7 μM and 457.7 μM P on HEPES rock phosphate and, 76.7 μM and 222.7 μM K on HRPF (feldspar), respectively, in minimal medium containing 50 mM glucose. Under N free minimal medium, similar effects of P and K solubilization were obtained. Hs (pJNK5) and Hs (pJNK6) inoculation increased the biomass, N, P, K content of rice plants (Gujarat – 17). These plants also accumulated 0.73 ng/g PQQ, and had improved growth and tolerance to CdCl2.Conclusions
Incorporation of pqq and gad gene clusters in H. seropedicae Z67 imparted additional plant growth promoting traits of P and K solubilization and ability to alleviate Cd toxicity to the host plant.3.
4.
Dagmar Waberski Anke Döhring Florencia Ardón Nadine Ritter Holm Zerbe Hans-Joachim Schuberth Marion Hewicker-Trautwein Karl Fritz Weitze Ronald HF Hunter 《Acta veterinaria Scandinavica》2006,48(1):13-8
Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilts. As a means of clarifying
this influence, the contribution of uterine lymphatics and their white cell populations has been examined. After duct visualisation
with Evan's blue, lymph was sampled from a mesometrial vessel in eight pre-ovulatory gilts whose uterine lumen was infused
simultaneously with whole semen in one ligated horn and saline in the contralateral ligated horn. Lymph was collected from
cannulated vessels for periods of up to four hours under general anaesthesia. Thereafter, mesometrial lymph nodes, utero-tubal
junction and uterine wall tissues were sampled. The proportion of nucleated cells in the sampled lymph increased towards the
end of the collection period, but erythrocytes were found in all instances preventing a meaningful differentiation and identification
of leukocytes. Prominent uterine lymph nodes were present in the mesometrium on both sides of the reproductive tract in 7
of 10 gilts. Differences in cellular contents were demonstrated between the side of the tract infused with semen and that
infused with saline control. Two of 4 gilts had lower values for CD4 (Cluster Differentiation) and 3 of 6 gilts higher values
for MHC II (Major Histocompatibility Complex) markers on the side challenged with semen. In contrast, values remained constant
for CD8 but ranged widely for CD18. Immunohistochemical analysis of uterine tissue samples for MHC II+ cells revealed significant
differences (P < 0.05) between the control and semen-treated ligated portions of the horns, as well as between the tissue
sample of uterine wall and that from the utero-tubal junction, but there were no significant differences for CD4+ cells. It
therefore remains plausible that semen-induced cytokines in the uterine lymph undergo counter-current transfer to the ipsilateral
ovary and accelerate the final maturation of pre-ovulatory Graafian follicles. 相似文献
5.
We report here an analysis of the structure of genetic diversity in cultivated sorghums. A core collection of 210 landraces representative of race, latitude of origin, response to day length, and production system was analysed with 74 RFLP probes dispersed throughout the genome. Multivariate analyses showed the specificity of the subrace guinea margaritiferum, as well as the geographical and racial pattern of genetic diversity. Neighbour-joining analysis revealed a clear differentiation between northern and southern equatorial African accessions. The presence of Asian accessions in these 2 major geographical poles for sorghum evolution indicated two introductions of sorghum into Asia. Morphological race also influenced the pattern of sorghum genetic diversity. A single predominant race was identified in 8 of 10 clusters of accessions, i.e., 1 kafir, 1 durra, 4 guinea, and 2 caudatum clusters. Guinea sorghums, with the exception of accessions in the margaritiferum subrace, clustered in 3 geographical groups, i.e., western African, southern African, and Asian guinea clusters; the latter two appeared more closely related. Caudatum were mainly distributed in 2 clusters, the African Great Lakes caudatum cluster and those African caudatum originating from other African regions. This last differentiation appears related to contrasting photoperiod responses. These results aid in the optimization of sampling accessions for introgression in breeding programs. 相似文献
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7.
Marcia Berrêdo-Pinho Dario E Kalume Paloma R Correa Leonardo HF Gomes Melissa P Pereira Renata F da Silva Luiz RR Castello-Branco Wim M Degrave Leila Mendonça-Lima 《BMC microbiology》2011,11(1):80
Background
Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB) and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO) affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE) and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs) from M. bovis BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection. 相似文献8.
Anton?C?van de Vusse Suzanne?GM?Stomp-van den Berg Alfons?HF?Kessels Wim?EJ?WeberEmail author 《BMC neurology》2004,4(1):13
Background
Complex Regional Pain Syndrome type one (CRPS I) or formerly Reflex Sympathetic Dystrophy (RSD) is a disabling syndrome, in which a painful limb is accompanied by varying symptoms. Neuropathic pain is a prominent feature of CRPS I, and is often refractory to treatment. Since gabapentin is an anticonvulsant with a proven analgesic effect in various neuropathic pain syndromes, we sought to study the efficacy of the anticonvulsant gabapentin as treatment for pain in patients with CRPS I. 相似文献9.
Thomas M Wishart Stephen HF MacDonald Philip E Chen Michael J Shipston Michael P Coleman Thomas H Gillingwater Richard R Ribchester 《Molecular neurodegeneration》2007,2(1):1-6
Background
The strain of MeCP2tm1.1Bird mice is a broadly used model for Rett syndrome. Because males carrying the invalidated MeCP2 locus are sterile, this strain has to be maintained in a heterozygous state. All animals therefore have to be genotyped at every generation to discriminate those carrying the invalidated allele (+/- females and y/- males) from those that do not. This is conveniently carried out by PCR on tail genomic DNA but because the primer pairs described initially for this purpose yield very similar size DNA bands on the WT and the KO alleles, this requires to carry out two independent PCR reactions on tail DNA preparations from all animals.Results
After cloning and sequencing the PCR fragment amplified on the KO allele, we tested several sets of primers that were designed to yield PCR fragments of different sizes on the KO and WT alleles.Conclusion
We have thus identified a set of three primers that allows for efficient genotyping of the animals by a single PCR reaction. Furthermore, using of this set of primers also resolves a recurrent problem related to the tendency of one of the initial primers to give rise to a non specific band because of its capacity to anneal at both ends of a repeated genomic element which we have identified as MurvyLTR. 相似文献10.
Cross validation (CV) was used to analyze the effects of different environments and different genotypic samples on estimates of the proportion of genotypic variance explained by QTL (p). Testcrosses of 344 F(3) maize lines grown in four environments were evaluated for a number of agronomic traits. In each of 200 replicated CV runs, this data set was subdivided into an estimation set (ES) and various test sets (TS). ES were used to map QTL and estimate p for each run (p(ES)) and its median (p(ES)) across all runs. The bias of these estimates was assessed by comparison with the median (p(TS.ES)) obtained from TS. We also used two independent validation samples derived from the same cross for further comparison. The median p(ES) showed a large upward bias compared to p(TS.ES). Environmental sampling generally had a smaller effect on the bias of p(ES) than genotypic sampling or both factors simultaneously. In independent validation, p(TS.ES) was on average only 50% of p(ES). A wide range among p(ES) reflected a large sampling error of these estimates. QTL frequency distributions and comparison of estimated QTL effects indicated a low precision of QTL localization and an upward bias in the absolute values of estimated QTL effects from ES. CV with data from three QTL studies reported in the literature yielded similar results as those obtained with maize testcrosses. We therefore recommend CV for obtaining asymptotically unbiased estimates of p and consequently a realistic assessment of the prospects of MAS. 相似文献