375 research outputs found
Prokaryotic assemblages and metagenomes in pelagic zones of the South China Sea
BACKGROUND: Prokaryotic microbes, the most abundant organisms in the ocean, are remarkably diverse. Despite numerous studies of marine prokaryotes, the zonation of their communities in pelagic zones has been poorly delineated. By exploiting the persistent stratification of the South China Sea (SCS), we performed a 2-year, large spatial scale (10, 100, 1000, and 3000 m) survey, which included a pilot study in 2006 and comprehensive sampling in 2007, to investigate the biological zonation of bacteria and archaea using 16S rRNA tag and shotgun metagenome sequencing. RESULTS: Alphaproteobacteria dominated the bacterial community in the surface SCS, where the abundance of Betaproteobacteria was seemingly associated with climatic activity. Gammaproteobacteria thrived in the deep SCS, where a noticeable amount of Cyanobacteria were also detected. Marine Groups II and III Euryarchaeota were predominant in the archaeal communities in the surface and deep SCS, respectively. Bacterial diversity was higher than archaeal diversity at all sampling depths in the SCS, and peaked at mid-depths, agreeing with the diversity pattern found in global water columns. Metagenomic analysis not only showed differential %GC values and genome sizes between the surface and deep SCS, but also demonstrated depth-dependent metabolic potentials, such as cobalamin biosynthesis at 10 m, osmoregulation at 100 m, signal transduction at 1000 m, and plasmid and phage replication at 3000 m. When compared with other oceans, urease at 10 m and both exonuclease and permease at 3000 m were more abundant in the SCS. Finally, enriched genes associated with nutrient assimilation in the sea surface and transposase in the deep-sea metagenomes exemplified the functional zonation in global oceans. CONCLUSIONS: Prokaryotic communities in the SCS stratified with depth, with maximal bacterial diversity at mid-depth, in accordance with global water columns. The SCS had functional zonation among depths and endemically enriched metabolic potentials at the study site, in contrast to other oceans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1434-3) contains supplementary material, which is available to authorized users
Incidence Rates of Enterovirus 71 Infections in Young Children during a Nationwide Epidemic in Taiwan, 2008–09
Enterovirus 71 (EV71) was first isolated in California, USA, in 1969. Since then, EV71 has been identified globally. Recently, EV71 caused several life-threatening outbreaks in young children in tropical Asia. Development of EV71 vaccines becomes national priority in several Asia countries including Taiwan. To design clinical trials of EV71 vaccines, age-specific incidence rates of EV71 infections are required to identify target populations, estimate disease burdens, select endpoints of clinical efficacy, and estimate sample size. In Taiwan, nationwide EV71 epidemics occurred every 3–4 years but age-specific incidences of EV71 infection are not available. In 2006, we initiated a prospective cohort study in northern Taiwan to recruit neonates and follow up them. In 2008–09, a nationwide EV71 epidemic occurred and we found that age-specific incidence rates of EV71 infection increased from 1.71 per 100 person-years at 0–6 months of age to 4.09, 5.74, and 4.97 per 100 person-years at 7–12, 13–24, and 25–36 months of age, respectively. The cumulative incidence rate was 15% by 36 months of age, and 29% of EV71 infections were asymptomatic in young children. These findings would be helpful to development of EV71 vaccines in Taiwan and other Asian tropical countries
Exploration of anti-cancer effects and mechanisms of Zuo-Jin-Wan and its alkaloid components in vitro and in orthotopic HepG2 xenograft immunocompetent mice
BACKGROUND: Zuo-Jin-Wan (ZJW), a two-herb formula consisting of Coptis chinensis (CC) and Evodia rutaecarpa (ER), is commonly used in traditional Chinese medicine for the treatment of cancers. However, the efficacies and mechanisms of ZJW and its alkaloid components on cancers are still unclear. METHODS: Here we investigated the anti-cancer effects and mechanisms of ZJW, CC, ER, berberine, and evodiamine in cells and in intrahepatic xenograft mice. RESULTS: Treatment of HepG2 cells with ZJW, CC, ER, berberine, and evodiamine significantly displayed cytotoxic effects in a dose- and time-dependent manner. Hierarchical cluster analysis of gene expression profiles showed that CC and ZJW shared a similar mechanism for the cytotoxic effects, suggesting that CC was the active ingredient of ZJW for anti-cancer activity. Network analysis further showed that c-myc was the likely key molecule involved in the regulation of ZJW-affected gene expression. A human hepatoma xenograft model was established by intrahepatic injection of HepG2 cells containing nuclear factor-κB-driven luciferase genes in immunocompetent mice. In vivo bioluminescence imaging showed that cells had been successfully transplanted in mouse liver. Oral administration of ZJW for 28 consecutive days led to a significant decrease in the accumulation of ascites, the ratio of tumor-to-liver, and the number of transplanted cells in livers. CONCLUSIONS: In conclusion, our findings suggested for the first time that ZJW significantly suppressed human cancer cell growth in orthotopic HepG2 xenograft-bearing immunocompetent mice. Moreover, c-myc might play a potent role in the cytotoxic mechanisms of ZJW, CC, ER, berberine, and evodiamine
Simple and Specific Dual-Wavelength Excitable Dye Staining for Glycoprotein Detection in Polyacrylamide Gels and Its Application in Glycoproteomics
In this study, a commercially available fluorescent dye, Lissamine rhodamine B sulfonyl hydrazine (LRSH), was designed to specifically stain the glycoproteins in polyacrylamide gels. Through the periodate/Schiff base mechanism, the fluorescent dye readily attaches to glycoproteins and the fluorescence can be simultaneously observed under either 305 nm or 532 nm excitation therefore, the dye-stained glycoproteins can be detected under a regular UV transilluminator or a more elegant laser-based gel scanner. The specificity and detection limit were examined using a standard protein mixture in polyacrylamide gels in this study. The application of this glycoprotein stain dye was further demonstrated using pregnancy urine samples. The fluorescent spots were further digested in gel and their identities confirmed through LC-MS/MS analysis and database searching. In addition, the N-glycosylation sites of LRSH-labeled uromodulin were readily mapped via in-gel PNGaseF deglycosylation and LC-MS/MS analysis, which indicated that this fluorescent dye labeling does not interfere with enzymatic deglycosylation. Hence, the application of this simple and specific dual-wavelength excitable dye staining in current glycoproteome research is promising
Biodistribution and pharmacokinetics of 188Re-liposomes and their comparative therapeutic efficacy with 5-fluorouracil in C26 colonic peritoneal carcinomatosis mice
Chia-Che Tsai1, Chih-Hsien Chang1, Liang-Cheng Chen1, Ya-Jen Chang1, Keng-Li Lan2, Yu-Hsien Wu1, Chin-Wei Hsu1, I-Hsiang Liu1, Chung-Li Ho1, Wan-Chi Lee1, Hsiao-Chiang Ni1, Tsui-Jung Chang1, Gann Ting3, Te-Wei Lee11Institute of Nuclear Energy Research, Taoyuan, 2Cancer Center, Taipei Veterans General Hospital, Taipei, 3National Health Research Institutes, Taipei, Taiwan, ROCBackground: Nanoliposomes are designed as carriers capable of packaging drugs through passive targeting tumor sites by enhanced permeability and retention (EPR) effects. In the present study the biodistribution, pharmacokinetics, micro single-photon emission computed tomography (micro-SPECT/CT) image, dosimetry, and therapeutic efficacy of 188Re-labeled nanoliposomes (188Re-liposomes) in a C26 colonic peritoneal carcinomatosis mouse model were evaluated.Methods: Colon carcinoma peritoneal metastatic BALB/c mice were intravenously administered 188Re-liposomes. Biodistribution and micro-SPECT/CT imaging were performed to determine the drug profile and targeting efficiency of 188Re-liposomes. Pharmacokinetics study was described by a noncompartmental model. The OLINDA|EXM® computer program was used for the dosimetry evaluation. For therapeutic efficacy, the survival, tumor, and ascites inhibition of mice after treatment with 188Re-liposomes and 5-fluorouracil (5-FU), respectively, were evaluated and compared.Results: In biodistribution, the highest uptake of 188Re-liposomes in tumor tissues (7.91% ± 2.02% of the injected dose per gram of tissue [%ID/g]) and a high tumor to muscle ratio (25.8 ± 6.1) were observed at 24 hours after intravenous administration. The pharmacokinetics of 188Re-liposomes showed high circulation time and high bioavailability (mean residence time [MRT] = 19.2 hours, area under the curve [AUC] = 820.4%ID/g*h). Micro-SPECT/CT imaging of 188Re-liposomes showed a high uptake and targeting in ascites, liver, spleen, and tumor. The results were correlated with images from autoradiography and biodistribution data. Dosimetry study revealed that the 188Re-liposomes did not cause high absorbed doses in normal tissue but did in small tumors. Radiotherapeutics with 188Re-liposomes provided better survival time (increased by 34.6% of life span; P < 0.05), tumor and ascites inhibition (decreased by 63.4% and 83.3% at 7 days after treatment; P < 0.05) in mice compared with chemotherapeutics of 5-fluorouracil (5-FU).Conclusion: The use of 188Re-liposomes for passively targeted tumor therapy had greater therapeutic effect than the currently clinically applied chemotherapeutics drug 5-FU in a colonic peritoneal carcinomatosis mouse model. This result suggests that 188Re-liposomes have potential benefit and are safe in treating peritoneal carcinomatasis of colon cancer.Keywords: biodistribution, dosimetry, 5-fluorouracil, micro-SPECT/CT, 188Re-liposome
Cardiac Myosin Binding Protein C and MAP-Kinase Activating Death Domain-Containing Gene Polymorphisms and Diastolic Heart Failure
OBJECTIVE: Myosin binding protein C (MYBPC3) plays a role in ventricular relaxation. The aim of the study was to investigate the association between cardiac myosin binding protein C (MYBPC3) gene polymorphisms and diastolic heart failure (DHF) in a human case-control study. METHODS: A total of 352 participants of 1752 consecutive patients from the National Taiwan University Hospital and its affiliated hospital were enrolled. 176 patients diagnosed with DHF confirmed by echocardiography were recruited. Controls were matched 1-to-1 by age, sex, hypertension, diabetes, renal function and medication use. We genotyped 12 single nucleotide polymorphisms (SNPs) according to HapMap Han Chinese Beijing databank across a 40 kb genetic region containing the MYBPC3 gene and the neighboring DNA sequences to capture 100% of haplotype variance in all SNPs with minor allele frequencies ≥ 5%. We also analyzed associations of these tagging SNPs and haplotypes with DHF and linkage disequilibrium (LD) structure of the MYBPC3 gene. RESULTS: In a single locus analysis, SNP rs2290149 was associated with DHF (allele-specific p = 0.004; permuted p = 0.031). The SNP with a minor allele frequency of 9.4%, had an odds ratio 2.14 (95% CI 1.25-3.66; p = 0.004) for the additive model and 2.06 for the autosomal dominant model (GG+GA : AA, 95% CI 1.17-3.63; p = 0.013), corresponding to a population attributable risk fraction of 12.02%. The haplotypes in a LD block of rs2290149 (C-C-G-C) was also significantly associated with DHF (odds ratio 2.10 (1.53-2.89); permuted p = 0.029). CONCLUSIONS: We identified a SNP (rs2290149) among the tagging SNP set that was significantly associated with early DHF in a Chinese population
Genome-Wide Association Study of Young-Onset Hypertension in the Han Chinese Population of Taiwan
Young-onset hypertension has a stronger genetic component than late-onset counterpart; thus, the identification of genes related to its susceptibility is a critical issue for the prevention and management of this disease. We carried out a two-stage association scan to map young-onset hypertension susceptibility genes. The first-stage analysis, a genome-wide association study, analyzed 175 matched case-control pairs; the second-stage analysis, a confirmatory association study, verified the results at the first stage based on a total of 1,008 patients and 1,008 controls. Single-locus association tests, multilocus association tests and pair-wise gene-gene interaction tests were performed to identify young-onset hypertension susceptibility genes. After considering stringent adjustments of multiple testing, gene annotation and single-nucleotide polymorphism (SNP) quality, four SNPs from two SNP triplets with strong association signals (−log10(p)>7) and 13 SNPs from 8 interactive SNP pairs with strong interactive signals (−log10(p)>8) were carefully re-examined. The confirmatory study verified the association for a SNP quartet 219 kb and 495 kb downstream of LOC344371 (a hypothetical gene) and RASGRP3 on chromosome 2p22.3, respectively. The latter has been implicated in the abnormal vascular responsiveness to endothelin-1 and angiotensin II in diabetic-hypertensive rats. Intrinsic synergy involving IMPG1 on chromosome 6q14.2-q15 was also verified. IMPG1 encodes interphotoreceptor matrix proteoglycan 1 which has cation binding capacity. The genes are novel hypertension targets identified in this first genome-wide hypertension association study of the Han Chinese population
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Clinical impact of pharmacogenetic risk variants in a large chinese cohort.
Incorporating pharmacogenetics into clinical practice promises to improve therapeutic outcomes by optimizing drug selection and dosage based on genetic factors affecting drug response. A key advantage of PGx-guided therapy is to decrease the likelihood of adverse events. To evaluate the clinical impact of PGx risk variants, we performed a retrospective study using genetic and clinical data from the largest Han Chinese cohort, comprising 486,956 individuals, assembled by the Taiwan Precision Medicine Initiative. We found that nearly all participants carried at least one genetic variant that could affect drug response, with many carrying multiple risk variants. Here we show the detailed analyses of four gene-drug pairs, azathioprine (NUDT15/TPMT), clopidogrel (CYP2C19), statins (ABCG2/CYP2C9/SLCO1B1), and NSAIDs (CYP2C9), for which sufficient data exists for statistical power. While the results validate previous findings that PGx risk variants are significantly associated with drug-related adverse events or ineffectiveness, the excess risk of adverse events or lack of efficacy is small compared to that found in those without the PGx risk variants, and most patients with PGx variants do not suffer from adverse events. Our results point to the complexity of implementing PGx in clinical practice and the need for integrative approaches to optimize precision medicine
Gastro-oesophageal reflux disease increases the risk of intensive care unit admittance and mechanical ventilation use among patients with chronic obstructive pulmonary disease: a nationwide population-based cohort study
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