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51.
Park JW  Kim S  Bahk YY 《Proteomics》2006,6(8):2433-2443
To elucidate an understanding into H-Ras protein network, we have established various oncogene H-Ras-expressing NIH/3T3 mouse embryonic fibroblast cell clones, which are expressing G12V H-Ras, G12R H-Ras, and G12V/T35S H-Ras proteins under the tight control of expression by an antibiotic doxycycline. Here we provide a catalog of proteome profiles in total cell lysate derived from the oncogenic and partial loss of function H-Ras-expressing NIH/3T3 cells. In this biological context, we compared total proteome changes by the combined methods of 2-DE, quantitative image analysis and MALDI-TOF-MS analysis both commonly in oncogenic and partial loss of function H-Ras expression system. Thus, we tried to dissect H-Ras signaling pathway, especially a downstream effector molecule, Raf in NIH/3T3 cells using proteomics tools. In this study, we centralized upon the proteome profile changes as common targets for oncogenic H-Ras and a partial loss of function H-Ras in the H-Ras-expressing cells. Thirteen protein spots were selected as what the staining intensities on the gels for 2-DE images from both kinds of cells were consistently changed in their protein expression level. Differentially regulated expression was further confirmed for some subsets of candidates by semiquantitative RT-PCR and Western blot analysis using specific antibodies. Taken together, our results obtained and present here show that the comparative analysis of proteome from oncogenic and partial loss of function H-Ras-expressing cells has yielded interpretable data to elucidate the protein network directly and/or indirectly.  相似文献   
52.
Adult mosquito surveillance was conducted using black light traps in August of 2006 and 2007 at Wangging county and Yanji city, Jilin Province, China to identify the distribution of anopheline mosquitoes in northern China. A total of 2459 female mosquitoes comprising three genera and eight species including Anopheles (Anopheles) lesteri, An. (Ano.) kleini, An. (Ano.) pullus, Culex inatomii, Cx. orientalis, Cx. pipiens, Cx. bitaeniorhynchus and Aedes vexans nipponii were collected. The most commonly collected species was An. kleini which had not been previously reported from China. Anopheles sinensis sensu stricto is commonly collected throughout China, but was not collected from these areas.  相似文献   
53.
Ultraviolet A (UVA) radiation (λ = 320–400 nm) is considered a major cause of human skin cancer. Pin1, a peptidyl prolyl isomerase, is overexpressed in most types of cancer tissues and plays an important role in cell proliferation and transformation. Here, we demonstrated that Pin1 expression was enhanced by low energy UVA (300–900 mJ/cm2) irradiation in both skin tissues of hairless mice and JB6 C141 epidermal cells. Exposure of epidermal cells to UVA radiation increased cell proliferation and cyclin D1 expression, and these changes were blocked by Pin1 inhibition. UVA irradiation also increased activator protein-1 (AP-1) minimal reporter activity and nuclear levels of c-Jun, but not c-Fos, in a Pin1-dependent manner. The increases in Pin1 expression and in AP-1 reporter activity in response to UVA were abolished by N-acetylcysteine (NAC) treatment. Finally, we found that pre-exposure of JB6 C141 cells to UVA potentiated EGF-inducible, anchorage-independent growth, and this effect was significantly suppressed by Pin1inhibition or by NAC.  相似文献   
54.

Background

The independent skeletal effect of thyrotropin (thyroid stimulating hormone, TSH) has been suggested in animal studies. However, clinical data on the association between bone loss and variations in TSH levels is inconsistent. This study aimed to investigate the relationship between TSH levels and bone mineral density (BMD).

Methods

We conducted a cross-sectional study with 37,431 subjects (33,052 cases with euthyroidism and 4,379 cases with subclinical thyroid dysfunction) aged over 35 years. We performed thyroid function tests and measured BMD at the lumbar spine, femur neck, and total hip.

Results

Levels of TSH and T3 were positively correlated in women (r = 0.076, P = 0.001) and uncorrelated in men. In both men and women, TSH levels correlated positively and T3 levels correlated negatively with BMD at all skeletal sites in age and body mass index adjusted analyses. BMD increased steadily with TSH levels from the subclinical hyperthyroid to subclinical hypothyroid range in subjects with T3 levels in the highest tertile (119.5–200.0 ng/dL), but was no longer significant in subjects with lower plasma T3 levels.

Conclusions

The variations in TSH levels within the euthyroid and subclinical range were positively correlated with BMD in healthy men and women. The negative effect of T3 on BMD appears to be compensated for by increased TSH in subjects with plasma T3 levels in the upper normal range.  相似文献   
55.
Simple Sequence Repeats (SSRs) represent short tandem duplications found within all eukaryotic organisms. To examine the distribution of SSRs in the genome of Brassica rapa ssp. pekinensis, SSRs from different genomic regions representing 17.7 Mb of genomic sequence were surveyed. SSRs appear more abundant in non-coding regions (86.6%) than in coding regions (13.4%). Comparison of SSR densities in different genomic regions demonstrated that SSR density was greatest within the 5'-flanking regions of the predicted genes. The proportion of different repeat motifs varied between genomic regions, with trinucleotide SSRs more prevalent in predicted coding regions, reflecting the codon structure in these regions. SSRs were also preferentially associated with gene-rich regions, with peri-centromeric heterochromatin SSRs mostly associated with retrotransposons. These results indicate that the distribution of SSRs in the genome is non-random. Comparison of SSR abundance between B. rapa and the closely related species Arabidopsis thaliana suggests a greater abundance of SSRs in B. rapa, which may be due to the proposed genome triplication. Our results provide a comprehensive view of SSR genomic distribution and evolution in Brassica for comparison with the sequenced genomes of A. thaliana and Oryza sativa.  相似文献   
56.
A combined ammonia gas absorption and nitrification was conducted in a single bioscrubber. The reactor was consisted of a bubble column (gas absorption) and a packed bed (nitrification) which contained poly-urethane foams with immobilized nitrifying activated sludge. The entering gas and scrubbing liquid were contacted countercurrently. The bubble column elimination capacity (EC) was 26.74 g NH3/m3 h at >99% ammonia gas removal and effluent gas concentration lower than 2 ppmv. Without ammonium supplement, EC can reach 35.66 g NH3/m3 h which is equivalently the highest tolerable ammonia loading rate of 700 g N/m3 day (1650 mg N/L) at the packed bed. At this level, 593 g N/m3-day ammonia removal rate was achieved via nitrification, dominated by ammonia oxidation. Partial recycling (R/Q = 0.5) of scrubbing solution reduced the secondary wastewater volume by producing 233% more concentrated nitrified products. Hydraulic retention time (HRT) of 24 h was found optimal for both processes (gas absorption and nitrification).  相似文献   
57.
Microbiomes exist in all ecosystems and are composed of diverse microbial communities. Perturbation to microbiomes brings about undesirable phenotypes in the hosts, resulting in diseases and disorders, and disturbs the balance of the associated ecosystems. Engineering of microbiomes can be used to modify structures of the microbiota and restore ecological balance. Consequently, microbiome engineering has been employed for improving human health and agricultural productivity. The importance and current applications of microbiome engineering, particularly in humans, animals, plants and soil is reviewed. Furthermore, we explore the challenges in engineering microbiome and the future of this field, thus providing perspectives and outlook of microbiome engineering.  相似文献   
58.
The tribe Trigonoderini (Hymenoptera: Pteromalidae) contains six genera (Gastracanthus Westwood, Janssoniella Kerrich, Miscogasteriella Girault, Platygerrhus Thomson, Plutothrix Förster and Trigonoderus Westwood). This tribe is recorded from South Korea for the first time. Two new species, Janssoniella albiclava Tselikh & Lee sp. nov. from South Korea and J. magna Tselikh & Lee sp. nov. from South Korea and the South Far East of Russia, are described. Eight species (Gastracanthus acutus (Kamijo), G. nigrescens Kamijo, Janssoniella intermedia Hedqvist, Miscogasteriella sulcate (Kamijo), Plutothrix scrobicula Kamijo, P. trifasciata (Thomson), Trigonoderus fraxini Yang and T. nigrocephalus Kamijo) are recorded from South Korea for the first time. The keys for identification of the Eastern–Palearctic species of Janssoniella and Gastracanthus are given and photos of diagnostic characters of the new species are provided.  相似文献   
59.
In the present study, we investigated the effects of a treadmill exercise on serum glucose levels and Ki67 and doublecortin (DCX) immunoreactivity, which is a marker of cell proliferation expressed during cell cycles except G0 and early G1 and a marker of progenitors differentiating into neurons, respectively, in the subgranular zone of the dentate gyrus (SZDG) using a type II diabetic model. At 6 weeks of age, Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats were put on a treadmill with or without running for 1 h/day/5 consecutive days at 22 m/min for 5 weeks. Body weight was significantly increased in the control (without running)-ZDF rats compared to that in the other groups. In the control groups blood glucose levels were increased by 392.7 mg/dl in the control-ZDF rats and by 143.3 mg/dl in the control-ZLC rats. However, in the exercise groups, blood glucose levels were similar between the exercise-ZLC and ZDF rats: The blood glucose levels were 110.0 and 118.2 mg/dl, respectively. Ki67 positive nuclei were detected in the SZDG in control and exercise groups. The number of Ki67 positive nuclei was significantly high in exercise groups compared to that in the control groups. In addition, Ki67 positive cells were abundant in ZLC groups compared to those in ZDF groups. DCX-immunoreactive structures in the control-ZDF rats were lower than that in the control-ZLC rats. In the exercise groups, DCX-immunoreactive structures (somata and processes with tertiary dendrites) and DCX protein levels were markedly increased in both the exercise-ZLC and ZDF rats compared to that in the control groups. These results suggest that a treadmill exercise reduces blood glucose levels in ZDF rats and increases cell proliferation and differentiation in the SZDG in ZLC and ZDF rats compared to those in control groups.  相似文献   
60.
Autophagy is a cellular degradation-recycling system for aggregated proteins and damaged organelles. Although dysregulated autophagy is implicated in various diseases including neurodegeneration, its role in pancreatic beta cells and glucose homeostasis has not been described. We produced mice with beta cell-specific deletion of Atg7 (autophagy-related 7). Atg7 mutant mice showed impaired glucose tolerance and decreased serum insulin level. beta cell mass and pancreatic insulin content were reduced because of increased apoptosis and decreased proliferation of beta cells. Physiological studies showed reduced basal and glucose-stimulated insulin secretion and impaired glucose-induced cytosolic Ca2+ transients in autophagy-deficient beta cells. Morphologic analysis revealed accumulation of ubiquitinated protein aggregates colocalized with p62, which was accompanied by mitochondrial swelling, endoplasmic reticulum distension, and vacuolar changes in beta cells. These results suggest that autophagy is necessary to maintain structure, mass and function of pancreatic beta cells, and its impairment causes insulin deficiency and hyperglycemia because of abnormal turnover and function of cellular organelles.  相似文献   
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