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51.
52.
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53.
Frank Fang-Yao Lee Hsiang-Chieh Chuang Nai-Yu Chen Govindarajulu Nagarajan Pinwen Peter Chiou 《PloS one》2015,10(5)
Toll-like receptor 9 (TLR9) recognizes and binds unmethylated CpG motifs in DNA, which are found in the genomes of bacteria and DNA viruses. In fish, Tlr9 is highly diverse, with the number of introns ranging from 0 to 4. A fish Tlr9 gene containing two introns has been reported to express two alternatively spliced isoforms, namely gTLR9A (full-length) and gTLR9B (with a truncated Cʹ-terminal signal transducing domain), whose regulation and function remain unclear. Here, we report a unique regulatory mechanism of gTLR9 signaling in orange-spotted grouper (Epinephelus coioides), whose gTlr9 sequence also contains two introns. We demonstrated that the grouper gTlr9 gene indeed has the capacity to produce two gTLR9 isoforms via alternative RNA splicing. We found that gTLR9B could function as a negative regulator to suppress gTLR9 signaling as demonstrated by the suppression of downstream gene expression. Following stimulation with CpG oligodeoxynucleotide (ODN), gTLR9A and gTLR9B were observed to translocate into endosomes and co-localize with ODN and the adaptor protein gMyD88. Both gTLR9A and gTLR9B could interact with gMyD88; however, gTLR9B could not interact with downstream IRAK4 and TRAF6. Further analysis of the expression profile of gTlr9A and gTlr9B upon immune-stimulation revealed that the two isoforms were differentially regulated in a time-dependent manner. Overall, these data suggest that fish TLR9B functions as a negative regulator, and that its temporal expression is mediated by alternative RNA splicing. This has not been observed in mammalian TLR9s and might have been acquired relatively recently in the evolution of fish. 相似文献
54.
Purpose
To estimate the rate of hospitalized eye trauma in Taiwan and investigate the role between principal and secondary diagnoses of such trauma.Methods
Nationwide fixed cohort study of 1,000,000 beneficiaries from the Taiwan Longitudinal Health Database was used and 4819 patients who were hospitalized for eye trauma during 1996-2010 were analyzed.Results
During 1996-2010, the incidence rates of hospitalized eye trauma (per 100 000 person-years) were 35.0 (95% confidence interval (CI), 34.0 to 36.0) for total diagnosis, 9.8 (95% CI, 9.3 to 10.3) for a principal diagnosis, and 25.3 (95% CI, 24.4 to 26.1) for a secondary diagnosis. The sex risk ratio was 3.1 for a principal diagnosis and 2.1 for a secondary diagnosis. The main causes of eye trauma were traffic accident, work accident, assault (among males <60 years of age), and falls (among elderly men and women). The proportion admitted to an ophthalmic department among those with a principal diagnosis of eye trauma (64.8%) was significantly higher than among those with a secondary diagnosis (2.3%) (p<.0001). Patients with a principal diagnosis of eye trauma had shorter hospital stays (7.1±10.2 days) and lower fatality (0.07%) than those with a secondary diagnosis of eye trauma (10.0±31.6 days and 0.3%, respectively).Conclusion
Data only from ophthalmic admissions tends to underestimate the true incidence rate of hospitalized eye trauma. Patients with a principal diagnosis of eye trauma had less severe injuries than did those with a secondary diagnosis. 相似文献55.
Objective
The transition from childhood to teenaged years is associated with increased testosterone and a decreased iron status. It is not clear whether higher testosterone levels cause the decreased iron status, and to what extent, obesity-related inflammation influences the iron-testosterone relationship. The aim of the present study was to examine relationships of testosterone, iron status, and anti-/proinflammatory cytokines in relation to nutritional status in boys and young adolescent Taiwanese males.Methods
In total, 137 boys aged 7~13 yr were included. Parameters for obesity, the iron status, testosterone, and inflammatory markers were evaluated.Results
Overweight and obese (ow/obese) boys had higher mean serum testosterone, interleukin (IL)-1β, and nitric oxide (NO) levels compared to their normal-weight counterparts (all p<0.05). Mean serum ferritin was slightly higher in ow/obese boys compared to normal-weight boys, but this did not reach statistical significance. A multiple linear regression showed that serum ferritin (β = -0.7470, p = 0.003) was inversely correlated with testosterone, while serum IL-10 (β = 0.3475, p = 0.009) was positively associated with testosterone after adjusting for covariates. When normal-weight boys were separately assessed from ow/obesity boys, the association between testosterone and serum ferritin became stronger (β = -0.9628, p<0.0001), but the association between testosterone and IL-10 became non-significant (β = 0.1140, p = 0.4065) after adjusting for covariates. In ow/obese boys, only IL-10 was weakly associated with serum testosterone (β = 0.6444, p = 0.051) after adjusting for age.Conclusions
Testosterone and serum ferritin are intrinsically interrelated but this relationship is weaker in ow/obese boys after adjusting for age. 相似文献56.
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
57.
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
58.
Yue Xu Diane R. Wagner Elena Bekerman Michael Chiou Aaron W. James Dennis Carter Michael T. Longaker 《PloS one》2010,5(6)
Background
Cytoskeletal tension is an intracellular mechanism through which cells convert a mechanical signal into a biochemical response, including production of cytokines and activation of various signaling pathways.Methods/Principal Findings
Adipose-derived stromal cells (ASCs) were allowed to spread into large cells by seeding them at a low-density (1,250 cells/cm2), which was observed to induce osteogenesis. Conversely, ASCs seeded at a high-density (25,000 cells/cm2) featured small cells that promoted adipogenesis. RhoA and actin filaments were altered by changes in cell size. Blocking actin polymerization by Cytochalasin D influenced cytoskeletal tension and differentiation of ASCs. To understand the potential regulatory mechanisms leading to actin cytoskeletal tension, cDNA microarray was performed on large and small ASCs. Connective tissue growth factor (CTGF) was identified as a major regulator of osteogenesis associated with RhoA mediated cytoskeletal tension. Subsequently, knock-down of CTGF by siRNA in ASCs inhibited this osteogenesis.Conclusions/Significance
We conclude that CTGF is important in the regulation of cytoskeletal tension mediated ASC osteogenic differentiation. 相似文献59.
Aims: In this study, three facile repetitive‐sequence PCR (rep‐PCR) techniques have been compared with the pulsed‐field gel electrophoresis (PFGE) method for differentiating the genetic relatedness of clinical Stenotrophomonas maltophilia isolates. Methods and Results: The dendrograms of 20 S. maltophilia isolates were constructed based on the data obtained from PFGE and three PCR‐based methods, i.e. enterobacterial repetitive intergenic consensus‐PCR (ERIC‐PCR), BOX‐PCR and repetitive extragenic palindromic‐PCR (REP‐PCR). When compared with PFGE, ERIC‐PCR displayed a much lower discriminatory power, whereas BOX‐PCR and REP‐PCR had a comparable discriminatory power for close genetic‐related isolates. Conclusion: BOX‐PCR and REP‐PCR can be convenient and effective methods for evaluating the close genetic relatedness of clinical S. maltophilia isolates. Significance and Impact of the Study: A rapid method for determining S. maltophilia’s close genetic relatedness provides a convenient tool for understanding the epidemiology of S. maltophilia. 相似文献
60.
The structure and function of polynucleotide phosphorylase (PNPase) and the exosome, as well as their associated RNA-helicases
proteins, are described in the light of recent studies. The picture raised is of an evolutionarily conserved RNA-degradation
machine which exonucleolytically degrades RNA from 3′ to 5′. In prokaryotes and in eukaryotic organelles, a trimeric complex
of PNPase forms a circular doughnut-shaped structure, in which the phosphorolysis catalytic sites are buried inside the barrel-shaped
complex, while the RNA binding domains create a pore where RNA enters, reminiscent of the protein degrading complex, the proteasome.
In some archaea and in the eukaryotes, several different proteins form a similar circle-shaped complex, the exosome, that
is responsible for 3′ to 5′ exonucleolytic degradation of RNA as part of the processing, quality control, and general RNA
degradation process. Both PNPase in prokaryotes and the exosome in eukaryotes are found in association with protein complexes
that notably include RNA helicase. 相似文献