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61.
Constrained multiple sequence alignment tool development and its application to RNase family alignment 总被引:1,自引:0,他引:1
Tang CY Lu CL Chang MD Tsai YT Sun YJ Chao KM Chang JM Chiou YH Wu CM Chang HT Chou WI 《Journal of bioinformatics and computational biology》2003,1(2):267-287
In this paper, we design a heuristic algorithm of computing a constrained multiple sequence alignment (CMSA for short) for guaranteeing that the generated alignment satisfies the user-specified constraints that some particular residues should be aligned together. If the number of residues needed to be aligned together is a constant alpha, then the time-complexity of our CMSA algorithm for aligning K sequences is O(alphaKn(4)), where n is the maximum of the lengths of sequences. In addition, we have built up such a CMSA software system and made several experiments on the RNase sequences, which mainly function in catalyzing the degradation of RNA molecules. The resulting alignments illustrate the practicability of our method. 相似文献
62.
Wang FI Chiou MT Chang CH Chang PH Liu CH Jeng CR Pang VF 《Proceedings of the National Science Council, Republic of China. Part B, Life sciences》2001,25(3):193-196
A 10-year-old male aardwolf (Proteles cristatus) was presented abdominal distention and emaciation for 3 months. Physical examination revealed firm abdominal masses with effusions. Cytologic assessment of the effusion showed uniform round tumor cells with a surface brush border. Necropsy showed white velvety masses covering the peritoneal surface of the liver, gall bladder, stomach, omentum, mesentery, spleen, intestine, abdominal wall and diaphragm. Histologic examination demonstrated papillary projections, lined with cuboidal tumor cells supported by fibrous connective tissue cores, arising from the serosa of visceral organs. Cytoplasmic vacuolation and a surface brush border were evident on some cells under light microscopy. Tumor cells stained positive for both cytokeratin (AE1/AE3) and vimentin. Electron microscopy showed prominent surface microvilli, rough endoplasmic reticulum, mitochondria and desmosomes in tumor cells. This may be the first reported case of peritoneal mesothelioma in a captive wild aardwolf. 相似文献
63.
Undecaprenyl pyrophosphate synthase (UPPs) catalyzes the condensation of eight molecules of isopentenyl pyrophosphate (IPP) with farnesyl pyrophosphate (FPP) to generate C(55) undecaprenyl pyrophosphate. We investigated the kinetics and mechanism of this reaction pathway using Escherichia coli UPPs. With a variety of different ratios of enzyme to substrate and FPP to IPP in the presence or absence of Triton, different product distributions were found. In the presence of excess FPP, the intermediates (C(25)-C(50)) accumulated. Under a condition with enzyme and FPP in excess of IPP, instead of C(20)-geranylgeranyl pyrophosphate, C(20), C(25), and C(30) were the major products. The UPPs steady-state k(cat) value (2.5 s(-1)) in the presence of 0.1% Triton was 190-fold larger than in the absence of Triton (0.013 s(-1)). The k(cat) value matched the rate constant of each IPP condensation obtained from the enzyme single-turnover experiments. This suggested that the IPP condensation rather than product release was the rate-limiting step in the presence of Triton. In the absence of Triton, the intermediates formed and disappeared in a similar manner under enzyme single turnover in contrast to the slow steady-state rate, which indicated a step after product generation was rate limiting. This was further supported by a burst product formation. Judging from the accumulation level of C(55), C(60), and C(65), their dissociation from the enzyme cannot be too slow and an even slower enzyme conformational change with a rate of 0.001 s(-1) might govern the UPPs reaction rate under the steady-state condition in the absence of Triton. 相似文献
64.
Fan CK Su KE Chung WC Tsai YJ Chiou HY Lin CF Su CT Tsai MC Chao PH 《Japanese journal of medical science & biology》1998,51(1):35-42
Atayal aborigines, living at an altitude of 1,500-1,600 m in northeastern Taiwan, still hunt for wild animals with the help of hunting dogs. In this study, the latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies in this community as a measure of their exposure to Toxoplasma gondii. The positive rates for sera anti-toxoplasma antibodies were 21.8% and 19.6%, respectively, in 422 Atayal and 51 hunting dogs tested. Neither of the positive rates were found to be significantly different between male (22.1%) and female Atayal (21.4%), or between humans (21.8%) and dogs (19.6%) (P > 0.05) when compared by the Chi-Squared test (chi 2-test). A significant difference was observed between the positive rates in adults (28.3%) and children (18.7%) (P < 0.05), and the age pattern of prevalence is consistent with an increasing duration of exposure to Toxoplasma gondii with age. The consumption of raw liver of wild animals or insufficiently cooked meat may be the major mode of transmission of toxoplasmosis in Atayal. 相似文献
65.
Chiou S Cerstiaens A Kotanen SP De Loof A Schoofs L 《Journal of insect physiology》1998,44(5-6):405-411
Acidic methanolic extracts of larvae of nine different insect species were found to contain substances that cause a lethal effect in the adult stage of the same species and of other species. These endogenous toxic substances, apparently being widely spread over the class of insects, were designated as paralysins, because of their immediate and observable paralytic effect upon injection. The developmental concentration curves of five different species of insects (Galleria mellonella (Lepidoptera), Neobellieria bullata (Diptera), Spodoptera frugiperda (Lepidoptera), Tenebrio molitor (Coleoptera) and Schistocerca gregaria (Orthoptera) indicate that the toxins are not present throughout all the developmental stages in the same concentration. The strongest paralytic activity was found in late instar larvae or in the early pupal stage. The temporal distribution of paralysins during development suggests that they might be involved in metamorphosis. 相似文献
66.
67.
Li-Nien Chien Quinn T. Ostrom Haley Gittleman Jia-Wei Lin Andrew E. Sloan Gene H. Barnett J. Bradley Elder Christopher McPherson Ronald Warnick Yung-Hsiao Chiang Chieh-Min Lin Lisa R. Rogers Hung-Yi Chiou Jill S. Barnholtz-Sloan 《PloS one》2015,10(6)
Background
High grade gliomas are the most common type of malignant brain tumor, and despite their rarity, cause significant morbidity and mortality. This study aimed to compare the treatment patterns of high grade glioma to examine survival patterns in patients who receive specific treatments between cohorts in Ohio and Taiwan.Method
Patients aged 18 years and older at age of diagnosis with World Health Organization (WHO) grade III or IV astrocytoma from 2007-2012 were selected from the Ohio Brain Tumor Study and the Taiwan Cancer Registry. The treatment information was derived from medical chart reviews in Ohio and National Health Insurance Research Data in Taiwan. Treatment examined included surgical procedure (brain biopsy and/or resection), radiotherapy (radiation and/or radiosurgery), and alkylating chemotherapy. Kaplan-Meier and parametric survival models were used to examine the effect of treatment on survival, adjusted for age, sex, and comorbidities.Results
294 patients in Ohio and 1,097 patients in Taiwan met the inclusion criteria. 70.3% patients in Ohio and 51.4% in Taiwan received surgical resection, followed by concurrent chemoradiation. Patients who received this treatment had the highest survival rate, with a 1-year survival rate of 72.8% in Ohio and 73.4% in Taiwan. Patients who did not receive surgical resection, followed by concurrent chemoradiation had an increased risk of death (hazard ratio of 5.03 [95% confidence interval (CI): 3.61-7.02] in Ohio and 1.49 [95% CI: 1.31-1.71] in Taiwan) after adjustment for age, sex, and comorbidities.Conclusion
Surgical resection followed by concurrent chemoradiation was associated with higher survival rate of patients with high grade glioma in both Ohio and Taiwan; however, one-third of patients in Ohio and half in Taiwan did not receive this treatment. 相似文献68.
A Systematic Approach to Species–Level Identification of Chile Pepper (Capsicum spp.) Seeds: Establishing the Groundwork for Tracking the Domestication and Movement of Chile Peppers through the Americas and Beyond The chile pepper (Capsicum spp.), a plant held in great esteem throughout history, was independently domesticated in a series of places including highland Bolivia, central Mexico, the Amazon, the Caribbean, and other locales with a particularly long history of cultivation and use in the central Andes of South America. Though identification of chile pepper species through fruit morphology is possible and has been utilized by botanists studying modern and archaeological specimens, species–level identification of Capsicum seeds has remained undetermined. Given the greater abundance of seed remains in the archaeological record due to the higher likelihood of preservation, the ability to identify specific Capsicum domesticates has profound implications for tracking the domestication and spread of chile peppers prehistorically through the Americas and historically through trade and exchange to the rest of the world. This article presents a systematic procedure to identify Capsicum seeds to the species level created by adopting a morphometric approach to compare attributes of modern Capsicum seeds to archaeological seeds. 相似文献
69.
Shen-Long Howng Chi-Ching Hwang Chia-Yi Hsu Meng-Yu Hsu Chun-Yen Teng Chia-Hua Chou Mei-Feng Lee Chia-Hung Wu Shean-Jaw Chiou Ann-Shung Lieu Joon-Khim Loh Chia-Ning Yang Chan-Shing Lin Yi-Ren Hong 《Molecular and cellular biochemistry》2010,339(1-2):23-33
The specificity and regulation of GSK3β are thought to involve in the docking interactions at core kinase domain because of the particular amino acid residues. Recent X-ray diffraction studies illuminated the relative binding residues on AxinGID and FRATtide for GSK3β docking and appeared that GSK3β Val267Gly (V267G) and Tyr288Phe (Y288F) could distinguish the direct interaction between AxinGID and FRATtide. In order to explore the mode that involved the binding of GSKIP to GSK3β and compare it with that of AxinGID and FRATtide, we pinpointed the binding sites of GSKIP to GSK3β through the single-point mutation of four corresponding sites within GSK3β (residues 260–300) as scaffold-binding region I (designated SBR-I260–300). Our data showed that these three binding proteins shared similar binding sites on GSK3β. We also found that the binding of GSK3β V267G mutant to GSKIP and AxinGID, but not that of Y288F mutant (effect on FRATtide), was affected. Further, based on the simulation data, the electron-density map of GSKIPtide bore closer similarity to the map AxinGID than to that of FRATtide. Interestingly, many C-terminal helix region point-mutants of GSK3β L359P, F362A, E366K, and L367P were able to eliminate the binding with FRATtide, but not AxinGID or GSKIP. In addition, CABYR exhibited a unique mode in binding to C-terminal helix region of GSK3β. Taken together, our data revealed that in addition to the core kinase domain, SBR-I260–300, another novel C-terminus helix region, designated SBR-II339–383, also appeared to participate in the recognition and specificity of GSK3β in binding to other specific proteins. 相似文献
70.
Yue Xu Diane R. Wagner Elena Bekerman Michael Chiou Aaron W. James Dennis Carter Michael T. Longaker 《PloS one》2010,5(6)