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991.
992.
The velvet complex containing VeA, VelB and LaeA has been showed to play critical roles in the regulation of secondary metabolism and diverse cellular processes in Aspergillus spp. In this study, we identified FgVelB, a homolog of Aspergillus nidulans VelB, from Fusarium graminearum using the BLASTP program. Disruption of FgVELB gene led to several phenotypic defects, including suppression of aerial hyphae formation, reduced hyphal hydrophobicity and highly increased conidiation. The mutant showed increased resistance to osmotic stress and cell wall-damaging agents, which may be related to a high level of glycerol accumulation in the mutant. Additionally, the mutant exhibited increased sensitivity to the phenylpyrrole fungicide fludioxonil. Ultrastructural and histochemical analyses revealed that conidia of FgVELB deletion mutant contained numerous lipid droplets. Pathogenicity assays showed FgVELB deletion mutant was impaired in virulence on flowering wheat head, which is consistent with the observation that FgVelB is involved in the regulation of deoxynivalenol biosynthesis in F. graminearum. All of the defects were restored by genetic complementation of the mutant with wild-type FgVELB gene. Yeast two hybrid assays showed that FgVelB does not interact with FgVeA. Taken together, results of this study indicated that FgVelB plays a critical role in the regulation of various cellular processes in F. graminearum.  相似文献   
993.
The bacterial community structure associated with filter materials in the recirculating aquaculture system of Scortum barcoo was investigated using the 16S rRNA gene clone library method. Preliminary results showed that the clone library constructed from the initial operation condition was characterized by 31 taxa of bacteria belonging to eight phyla including Proteobacteria, Acidobacteria, Firmicutes, Fusobacteria, Sphingobacteria, Bacteroidetes, Verrucomicrobiae, and Actinobacteria. There were 14 taxa of bacteria belonging to four phyla including Proteobacteria, Acidobacteria, Planctomycetacia, and Nitrospirae from the stable operation condition where the water quality was well maintained. Nitrospirae was only found under the stable operation condition in this study. Our results further indicated that Nitrospira was dominated by members of the Nitrospira sp. lineages, with a minor fraction related to Nitrospira moscoviensis and an unknown Nitrospira cluster. These great differences of both diversity and composition between two operation conditions suggested that the composition of the microbial community varied with the degree of water quality in the recirculating aquaculture system of S.?barcoo.  相似文献   
994.

Purpose

Genetic basis of Developmental dysplasia of the hip (DDH) remains largely unknown. To find new susceptibility genes for DDH, we carried out a genome-wide association study (GWAS) for DDH.

Methods

We enrolled 386 radiology confirmed DDH patients and 558 healthy controls (Set A) to conduct a genome-wide association study (GWAS). Quality-control was conducted at both the sample and single nucleotide polymorphism (SNP) levels. We then conducted a subsequent case-control study to replicate the association between a promising loci, rs6060373 in UQCC gene and DDH in an independent set of 755 cases and 944 controls (set B).

Results

In the DDH GWAS discovering stage, 51 SNPs showed significance of less than 10-4, and another 577 SNPs showed significance of less than 10-3. In UQCC, all the 12 genotyped SNPs showed as promising risk loci. Genotyping of rs6060373 in set A showed the minor allele A as a promising risk allele (p = 4.82*10-7). In set A, the odds ratio of allele A was 1.77. Genotyping of rs6060373 in Set B produced another significant result (p = 0.0338) with an odds ratio of 1.18 for risk allele A. Combining set A and set B, we identified a total p value of 3.63*10-6 with the odds ratio of 1.35 (1.19–1.53) for allele A.

Conclusion

Our study demonstrates common variants of UQCC, specifically rs6060373, are associated with DDH in Han Chinese population.  相似文献   
995.
996.

Background

Aortocaval fistula (AV) in rat is a unique model of volume-overload congestive heart failure and cardiac hypertrophy. Living donor kidney transplantation is regarded as beneficial to allograft recipients and not particularly detrimental to the donors. Impact of AV on animals with mild renal dysfunction is not fully understood. In this study, we explored the effects of AV in unilateral nephrectomized (UNX) rats.

Methods

Adult male Sprague-Dawley (SD) rats were divided into Sham (n = 10), UNX (right kidney remove, n = 10), AV (AV established between the levels of renal arteries and iliac bifurcation, n = 18) and UNX+AV (AV at one week after UNX, n = 22), respectively. Renal outcome was measured by glomerular filtration rate, effective renal plasma flow, fractional excretion of sodium, albuminuria, plasma creatinine, and cystatin C. Focal glomerulosclerosis (FGS) incidence was evaluated by renal histology. Cardiac function was measured by echocardiography and hemodynamic measurements.

Results

UNX alone induced compensatory left kidney enlargement, increased plasma creatinine and cystatin C levels, and slightly reduced glomerular filtration rate and increased FGS. AV induced significant cardiac enlargement and hypertrophy and reduced cardiac function and increased FGS, these changes were aggravated in UNX+AV rats.

Conclusions

Although UNX only induces minor renal dysfunction, additional chronic volume overload placement during the adaptation phase of the remaining kidney is associated with aggravated cardiac dysfunction and remodeling in UNX rats, suggesting special medical care is required for UNX or congenital monokidney subjects in case of chronic volume overload as in the case of pregnancy and hyperthyroidism to prevent further adverse cardiorenal events in these individuals.  相似文献   
997.
Abstract In vitro derivation of oocytes from embryonic stem (ES) cells has the potential to be an important tool for studying oogenesis as well as advancing the field of therapeutic cloning by providing an alternative source of oocytes. Here, we demonstrate a novel, two-step method for inducing mouse ES cells to differentiate into oocyte-like cells using mouse ovarian granulosa cells. First, primordial germ cells (PGCs) were differentiated within the embryonic body (EB) cells around day 4 as defined by the expression of PGC-specific markers and were distinguished from undifferentiated ES cells. Second, day 4 EB cells were co-cultured with ovarian granulosa cells. After 10 days, these cells formed germ cell colonies as indicated by the expression of the two germ cell markers Mvh and SCP3. These cells also expressed the oocyte-specific genes Fig α, GDF-9 , and ZP1-3 but not any testis-specific genes by RT-PCR analysis. EB cultured alone or cultured in granulosa cell-conditioned medium did not express any of these oocyte-specific markers. In addition, EB co-cultured with Chinese hamster ovary (CHO) cells or cultured in CHO cell-conditioned medium did not express all of these oocyte-specific markers. Immunocytochemistry analysis using Mvh and GDF-9 antibodies confirmed that some Mvh and GDF-9 double-positive oocyte-like cells were generated within the germ cell colonies. Our results demonstrate that granulosa cells were effective in inducing the differentiation of ES cell-derived PGCs into oocyte-like cells through direct cell-to-cell contacts. Our method offers a novel in vitro system for studying oogenesis; in particular, for studying the interactions between PGCs and granulosa cells.  相似文献   
998.
The synthesis and follow-up SAR studies of our development candidate 1 by incorporating 2-aryl-4-oxazolylmethoxy and 2-aryl-4-thiazolylmethoxy moieties into the oxybenzylglycine framework of the PPARα/γ dual agonist muraglitazar is described. SAR studies indicate that different substituents on the aryloxazole/thiazole moieties as well as the choice of carbamate substituent on the glycine moiety can significantly modulate the selectivity of PPARα versus PPARγ. Potent, highly selective PPARα activators 2a and 2l, as well as PPARα activators with significant PPARγ activity, such as 2s, were identified. The in vivo pharmacology of these compounds in preclinical animal models as well as their ADME profiles are discussed.  相似文献   
999.
Burkholderia cepacia complex (Bcc) is a group of bacteria with conflicting biological characteristics, which make them simultaneously beneficial and harmful to humans. They have been exploited for biocontrol, bioremediation, and plant growth promotion. However, their capacity as opportunistic bacteria that infect humans restricts their biotechnological applications. Therefore, the risks of using these bacteria should be assessed. In this study, Burkholderia multivorans WS-FJ9 originally isolated from pine rhizosphere, which was shown to be efficient in solubilizing phosphate, was evaluated with respect to its biosafety, colonization in poplar rhizosphere, and growth-promoting effects on poplar seedlings. Pathogenicity of B. multivorans WS-FJ9 on plants was determined experimentally using onion and tobacco as model plants. Onion bulb inoculated with B. multivorans WS-FJ9 showed slight hypersensitive responses around the inoculation points, but effects were not detectable based on the inner color and odor of the onion. Tobacco leaves inoculated with B. multivorans WS-FJ9 exhibited slightly water-soaked spots around the inoculation points, which did not expand or develop into lesions even with repeated incubation. Pathogenicity of the strain in alfalfa, which has been suggested as an alternative Bcc model for mice, was not detectable. Results from gene-specific polymerase chain reactions showed that the tested B. multivorans WS-FJ9 strain did not possess the BCESM and cblA virulence genes. Scanning electron microscopy revealed that the colonization of the WS-FJ9 strain reached 1.4?×?104 colony forming units (cfu)?g?1 rhizosphere soil on day 77 post-inoculation. The B. multivorans WS-FJ9 strain could colonize the rhizosphere as well as the root tissues and cells of poplars. Greenhouse evaluations in both sterilized and non-sterilized soils indicated that B. multivorans WS-FJ9 significantly promoted growth in height, root collar diameter, and plant biomass of inoculated poplar seedlings compared with controls. Phosphorus contents of roots and stems of treated seedlings were 0.57 and 0.55 mg g?1 higher than those of the controls, respectively. Phosphorus content was lower in the rhizosphere soils by an average of 1.03 mg g?1 compared with controls. The results demonstrated that B. multivorans WS-FJ9 is a nonpathogenic strain that could colonize the roots and significantly promote the growth of poplar seedlings.  相似文献   
1000.
摘要:【目的】筛选一株可以将琼胶转化为新琼寡糖的菌株,并对该菌株进行鉴定。【方法】从紫菜生长区域采集紫菜和该区域海水,用含1‰琼胶的培养基富集培养,逐级稀释涂布、平板划线进行初筛,液体培养进行复筛,DNS法测定琼胶降解产物中还原糖的含量。通过16S rDNA序列分析,结合菌体形态、菌落特征及生理生化特性,确立该菌的系统发育学地位。【结果】从紫菜振荡液中筛选出一株可以产琼胶酶的菌株HJPHYXJ-1,该菌属于革兰氏阴性菌,16S rDNA序列同源性与需钠弧菌(Vibrio natriegens)的达到了99%,结合形态特征和生理生化实验结果鉴定该菌为需钠弧菌。HPLC法测定酶解产物为新琼寡糖。【结论】HJPHYXJ-1被筛选用于转化琼胶,酶解产物的聚合度在2-12 之间,是以二糖为单位的新琼寡糖,该菌产生的酶为β-琼胶酶。  相似文献   
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