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111.
Gene expression variation increase in trisomy 21 tissues 总被引:1,自引:0,他引:1
Ching Yu Chou Li Yu Liu Chien Yu Chen Cheng Hsien Tsai Hsiao Lin Hwa Li Yun Chang Yi Shing Lin Fon Jou Hsieh 《Mammalian genome》2008,19(6):398-405
Congenital development disorders with variable severity occur in trisomy 21. However, how these phenotypic abnormalities develop
with variations remains elusive. We hypothesize that the differences in euploid gene expression variation among trisomy 21
tissues are caused by the presence of an extra copy of chromosome 21 and may contribute to the phenotypic variations in Down
syndrome. We used DNA microarray to measure the differences in gene expression variance between four human trisomy 21 and
six euploid amniocytes. The three publicly available data sets of fetal brains, adult brains, and fetal hearts were also analyzed.
The numbers of euploid genes with greater variance were significantly higher in all four kinds of trisomy 21 tissues (p < 0.01) than in the corresponding euploid tissues. Seventeen euploid genes with significantly different variance between
trisomy 21 and euploid amniocytes were found using the F test. In summary, there is a set of euploid genes that shows greater variance of expression in human trisomy 21 tissues than
in euploid tissues. This change may contribute to producing the variable phenotypic abnormalities observed in Down syndrome. 相似文献
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114.
Yuan Ru Tsai Su Jing Yang Shih Sheng Jiang Shu Jin Ko Shu Hsien Hung Soong Yu Kuo Rong Long Pan 《Journal of Protein Chemistry》1998,17(2):161-172
A high-hydrostatic-pressure technique was employed to study the structure-function relationship of plant vacuolar H+-ATPase from etiolated mung bean seedlings (Vigna radiata L.). When isolated vacuolar H+-ATPase was subjected to hydrostatic pressure, the activity of ATP hydrolysis was markedly inhibited in a time-, protein concentration- and pressure-dependent manner. The pressure treatment decreased both V
max and K
m of solubilized vacuolar H+-ATPase, implying an increase in ATP binding affinity, but a decrease in the ATP hydrolysis activity. Physiological substrate, Mg2+-ATP, augmented the loss of enzymatic activity upon pressure treatment. However, ADP, AMP, and Pi exerted substantial protective effects against pressurization. Steady-state ATP hydrolysis was more sensitive to pressurization than single-site ATPase activity. The inactivation of solubilized vacuolar H+-ATPase by pressure may result from changes in protein–protein interaction. The conformational change of solubilized vacuolar H+-ATPase induced by hydrostatic pressure was further determined by spectroscopic techniques. The inhibition of vacuolar H+-ATPase under pressurization involved at least two steps. Taken together, our work indicates that subunit–subunit interaction is crucial for the integrity and the function of plant vacuolar H+-ATPase. It is also suggested that the assembly of the vacuolar H+-ATPase complex is probably not random, but follows a sequestered pathway. 相似文献
115.
116.
Chen Yuan Chiang Kuan Jen Bai Hsien Ho Lin Shun Tien Chien Jen Jyh Lee Donald A. Enarson Ting-I Lee Ming-Chih Yu 《PloS one》2015,10(3)
Background
To assess the influence of diabetes mellitus (DM), glycemic control, and diabetes-related comorbidities on manifestations and outcome of treatment of pulmonary tuberculosis (TB).Methodology/Principal Findings
Culture positive pulmonary TB patients notified to health authorities in three hospitals in Taiwan from 2005–2010 were investigated. Glycemic control was assessed by glycated haemoglobin A1C (HbA1C) and diabetic patients were categorized into 3 groups: HbA1C<7%, HbA1C 7–9%, HbA1C>9%. 1,473 (705 with DM and 768 without DM) patients were enrolled. Of the 705 diabetic patients, 82 (11.6%) had pretreatment HbA1C<7%, 152 (21.6%) 7%–9%, 276 (39.2%) >9%, and 195 (27.7%) had no information of HbA1C. The proportions of patients with any symptom, cough, hemoptysis, tiredness and weight loss were all highest in diabetic patients with HbA1C>9%. In multivariate analysis adjusted for age, sex, smoking, and drug resistance, diabetic patients with HbA1C>9% (adjOR 3.55, 95% CI 2.40–5.25) and HbA1C 7–9% (adjOR 1.62, 95% CI 1.07–2.44) were significantly more likely to be smear positive as compared with non-diabetic patients, but not those with HbA1C<7% (adjOR 1.16, 95% CI 0.70–1.92). The influence of DM on outcome of TB treatment was not proportionately related to HbA1C, but mainly mediated through diabetes-related comorbidities. Patients with diabetes-related comorbidities had an increased risk of unfavorable outcome (adjOR 3.38, 95% CI 2.19–5.22, p<0.001) and one year mortality (adjOR 2.80, 95% CI 1.89–4.16). However, diabetes was not associated with amplification of resistance to isoniazid (p = 0.363) or to rifampicin (p = 0.344).Conclusions/Significance
Poor glycemic control is associated with poor TB treatment outcome and improved glycemic control may reduce the influence of diabetes on TB. 相似文献117.
Robert J. Lennox Gale A. Bravener Hsien‐Yung Lin Charles P. Madenjian Andrew M. Muir Christina K. Remucal Kelly F. Robinson Andrew M. Rous Michael J. Siefkes Michael P. Wilkie Daniel P. Zielinski Steven J. Cooke 《Global Change Biology》2020,26(3):1118-1137
Control programs are implemented to mitigate the damage caused by invasive species worldwide. In the highly invaded Great Lakes, the climate is expected to become warmer with more extreme weather and variable precipitation, resulting in shorter iced‐over periods and variable tributary flows as well as changes to pH and river hydrology and hydrogeomorphology. We review how climate change influences physiology, behavior, and demography of a damaging invasive species, sea lamprey (Petromyzon marinus), in the Great Lakes, and the consequences for sea lamprey control efforts. Sea lamprey control relies on surveys to monitor abundance of larval sea lamprey in Great Lakes tributaries. The abundance of parasitic, juvenile sea lampreys in the lakes is calculated by surveying wounding rates on lake trout (Salvelinus namaycush), and trap surveys are used to enumerate adult spawning runs. Chemical control using lampricides (i.e., lamprey pesticides) to target larval sea lamprey and barriers to prevent adult lamprey from reaching spawning grounds are the most important tools used for sea lamprey population control. We describe how climate change could affect larval survival in rivers, growth and maturation in lakes, phenology and the spawning migration as adults return to rivers, and the overall abundance and distribution of sea lamprey in the Great Lakes. Our review suggests that Great Lakes sea lamprey may benefit from climate change with longer growing seasons, more rapid growth, and greater access to spawning habitat, but uncertainties remain about the future availability and suitability of larval habitats. Consideration of the biology of invasive species and adaptation of the timing, intensity, and frequency of control efforts is critical to the management of biological invasions in a changing world, such as sea lamprey in the Great Lakes. 相似文献
118.
Yu‐Cheng Hsu Shou‐Hsien Li Yao‐Sung Lin Mark T. Philippart Lucia Liu Severinghaus 《Journal of avian biology》2006,37(1):36-40
The genetic mating system is known for only a few species of owls. Most of them are genetically monogamous. The Lanyu scops owl Otus elegans botelensis breeds in high density in the forests of Lanyu (Orchid Island), southeast of Taiwan. Because extra‐pair copulations (EPCs) have frequently been observed, we suspected a high degree of extra‐pair fertilizations (EPFs). Through intensive field observations we quantified both within‐pair and extra‐pair copulations of this owl, and used a set of microsatellite loci to assign the parentage of 200 offspring from 108 families collected between 1999 and 2004. Among copulations for which we could identify both participants, 19.77% were EPC. However, no EPC was observed in the period just before egg laying. We found only two cases of parentage mismatch among 108 broods. The first case was most likely a case of brood usurpation, which would be the first case reported in the Strigidae. The second case was an EPF resulting in one offspring. Our study found that parentage mismatch in the Lanyu scops owls to be extremely low, therefore reproductive success can be estimated accurately by simply counting chicks in nests. 相似文献
119.
This study attempted to determine the optimal temperature and initial cultivation pH by conducting a series of batch tests
in stirred-tank bioreactor using fructose-producing wastewater as an organic substrate. The bioreactor temperature was controlled
at 35–55°C with an initial pH of 4–8. Hydrogen production efficiency was assessed using specific hydrogen production potential
(SHPP) and the maximum specific hydrogen production rate (SHPRm). Experimental results indicated that temperature and initial pH markedly affected SHPP and SHPRm, volatile fatty acids distribution as well as the ratio of butyrate/acetate (BHu/HAc). Two-fold higher SHPP and SHPRm were obtained at thermophilic condition (55°C) than those at mesophilic condition (35°C). The optimal initial pH was 6 for
hydrogen production with peak values of SHPP of 166.8 ml-H2/g-COD and SHPRm of 26.7 ml-H2/g-VSS-h for fructose-processing wastewater. Molasses-processing wastewater had a higher SHPP (187.0 ml-H2/g-COD) and SHPRm (42.7 ml-H2/gVSS-h) than fructose-processing wastewater at pH 6. The DGGE profiles indicated that molasses-processing wastewater is a
better substrate than fructose-processing wastewater for growth of hydrogen-producing bacteria due to the high staining intensity
of bands. 相似文献
120.
The interspecific relationships among extant laughingthrushes have been unclear for a long time and this has resulted in a confusing taxonomic history. Recent advances in molecular methods have greatly improved the resolution of the phylogeny of birds; however, little works has been done on this specific group because of the inaccessibility to many species. This diverse group includes 50 species mostly distributed in South China and South-east Asia, and were traditionally arranged into the genus Garrulax , for which the non monophyly had been questioned by previous molecular studies. In this study, we infer a phylogeny for 23 Garrulax species and 20 species from close related genera. Mitochondrial data or combined with nuclear sequences both indicate paraphyly of Garrulax , dividing Garrulax species into two groups. Based on these results, we suggest resurrecting the genus name Trochalopteron Blyth, 1843 for one group and retaining Garrulax for the other pending further study. Using dating methods with a secondary calibration point, we develop a profile of the speciation history of laughingthrushes, which suggests that the Hengduan Mountains might not be the centre of origin for these birds as previously suggested. 相似文献