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11.
H W Peng T S Su S H Han C K Ho C H Ho K N Ching B N Chiang 《Journal of medical virology》1988,24(4):405-412
In order to study the prevalence of hepatitis B virus (HBV) in the adult population of Taiwan, we screened for the presence of HBV DNA in 205 blood samples from adult (20-59-year-old) volunteers. According to the serological markers of HBV, samples were divided into three groups: group I (173 subjects) was negative for both HBsAg and HBeAg; group II (14 subjects) was positive for both HBsAg and HBeAg; and group III consisted of 18 subjects who were HBsAg-positive but HBeAg-negative. Plasma HBV DNA was not detected in group I, but it was found in 85.7% and 11.8% of samples in group II and group III, respectively. A free-form HBV DNA was found in 14.3% of the leukocyte samples in group II. Furthermore, an integrated form of HBV DNA was detected in the leukocytes of two cases of group I who remained healthy based on clinical data. HBV DNA was also detected in the spermatozoa and liver cells of one of the cases. 相似文献
12.
Shyh Ren Chiang Hung Jen Tang Ping Chin Chang Kuo Chen Cheng Wen Chien Ko Chung Hua Chen Yin Ching Chuang 《Journal of microbiology, immunology, and infection》2007,40(2):123-133
BACKGROUND AND PURPOSE: Vibrio vulnificus causes primary bacteremia and necrotizing wound infection, leading to high morbidity and mortality in humans. This study aimed to evaluate the antimicrobial effect of cefotaxime and minocycline on proinflammatory cytokine levels in a murine model of V. vulnificus infection. METHODS: We investigated the dynamics of proinflammatory cytokines and their modulation by antimicrobial agents using a murine model of V. vulnificus infection. The change in cytokine levels was followed over a time course to identify the antimicrobial activity of the drugs against V. vulnificus. BALB/c female mice were challenged with an intraperitoneal infection using a clinical invasive isolate of Vv05191, and their cytokine levels were assayed over various time points. RESULTS: Serum levels of tumor necrosis factor-alpha, interleukin (IL)-1 beta, and IL-6 post-infection were found to be inoculum dose-dependent and positively correlated to the subsequent fatality rate in the infected mice. With an inoculum of 6.6 x 10(6) colony-forming units and intraperitoneal administration of cefotaxime, minocycline, or both, the serum and peritoneal fluid cytokine levels increased and then declined gradually. Comparison of the 3 antimicrobial regimens revealed that the magnitude of reduction in cytokine levels was greatest in mice treated with cefotaxime-minocycline combination. Moreover, the peritoneal fluid cytokine level in the combination group was significantly lower than that in the groups treated with minocycline or cefotaxime alone. CONCLUSIONS: The current results support the superiority of the combination therapy in treating invasive V. vulnificus infections. 相似文献
13.
Christina T Teng Wesley Gladwell Clara Beard David Walmer Ching S Teng Robert Brenner 《Molecular human reproduction》2002,8(1):58-67
We have previously shown that the estrogen responsiveness of the human lactoferrin gene in a transient transfection system is mediated through an imperfect estrogen response element (ERE) and a steroidogenic factor 1 binding element (SFRE) 26 bp upstream from ERE. Reporter constructs containing SFRE and ERE respond to estrogen stimulation in a dose-dependent manner, whereas mutations at either one of the response elements severely impaired the estrogen responsiveness. In this study, we demonstrated that estrogen receptor (ERalpha) binds to the human lactoferrin gene ERE and forms two complexes in an electrophoresis mobility shift assay (EMSA). These complexes could be supershifted by an antibody to ERalpha. We also showed that in normal cycling women, lactoferrin gene expression in the endometrium increases during the proliferative phase and diminishes during the luteal phase. This in-vivo study thus supported the finding from transient transfection experiments that the human lactoferrin gene expression is elevated in an environment with a high level of estrogen. The estrogen effect on lactoferrin gene expression in the rhesus monkey endometrium was studied by Western blotting and immunohistochemistry. The immunohistochemistry results showed that immunoreactive lactoferrin protein was not detectable in the untreated ovariectomized monkey endometrium, was elevated by estrogen treatment, and was suppressed by sequential, combined estrogen plus progesterone treatment. In conclusion, this study has shown that lactoferrin gene expression is responsive to estrogen in primate endometrium. 相似文献
14.
Purification of a baculovirus-expressed hepatitis E virus structural protein and utility in an enzyme-linked immunosorbent assay. 总被引:2,自引:0,他引:2 下载免费PDF全文
We report on the purification of the full-length structural protein encoded by open reading frame 2 (ORF-2) of hepatitis E virus. The ORF-2 protein, expressed in Sf9 cells by using a recombinant baculovirus vector system, was successfully purified to homogeneity. Gel electrophoresis of the purified ORF-2 protein showed a single polypeptide of 75 kDa by Coomassie blue staining and by Western blot (immunoblot) analysis. We demonstrated that the partially purified ORF-2 protein could be used successfully in a sensitive and specific enzyme-linked immunosorbent assay for the detection of antibodies to hepatitis E virus. 相似文献
15.
Comparison of ethanol versus formalin fixation on preservation of histology and RNA in laser capture microdissected brain tissues 总被引:1,自引:0,他引:1
Su JM Perlaky L Li XN Leung HC Antalffy B Armstrong D Lau CC 《Brain pathology (Zurich, Switzerland)》2004,14(2):175-182
Although RNA can be retrieved from formalin-fixed, paraffin-embedded (FFPE) tissues, the yield is low, and the RNA is fragmented. Recent advances in gene expression profiling underscore the importance of identifying a fixative that preserves histology and mRNA. We demonstrated that, for immersion fixation of brains, 70% ethanol is superior to formalin for mRNA preservation. RNA yield from ethanol-fixed tissues was 70% of the yield from fresh frozen specimens, but only a negligible quantity was recovered from formalin-fixed tissues. RNA from ethanol-fixed brains showed integrity comparable to RNA from fresh frozen tissues, and RT-PCR using RNA from ethanol-fixed tissues was consistently successful. RNA from FFPE tissues composed of low-molecular weight fragments, and their use in RT-PCR failed repeatedly. The yield and quality of RNA from ethanol-fixed brains were unaffected after immersion at 4 degrees C for 2 weeks. In a blinded comparison to FFPE tissues, ethanol-fixed specimens were judged to show comparable histology and superior immunostaining. After laser capture microdissection (LCM), we failed to recover mRNA from FFPE tissues but retrieved mRNA from ethanol-fixed tissues for RT-PCR and cDNA microarray analysis. We conclude that 70% ethanol preserves RNA integrity and is suitable for expression profiling of brain tissues by LCM and cDNA microarray. 相似文献
16.
A selenium-containing nucleoside at the first position of the anticodon in seleno-tRNAGlu from Clostridium sticklandii. 总被引:4,自引:3,他引:1 下载免费PDF全文
W M Ching B Alzner-DeWeerd T C Stadtman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(2):347-350
In previous studies, the single selenonucleoside component of a selenium-containing tRNAGlu isolated from Clostridium sticklandii has been shown to be 5-methyl-aminomethyl-2-selenouridine. Here, we show that this selenonucleoside is most likely located at the "wobble" position of the anticodon of the clostridial seleno-tRNAGlu. Nuclease T1 digestion of this seleno-tRNAGlu generated one major selenium-containing oligonucleotide (25 bases long). The selenium-containing residue within this oligonucleotide was located by sequence analysis of the oligonucleotide before and after removal of selenium by treatment with cyanogen bromide. The sequence of this oligonucleotide, A-A-C-C-G-C-C-C-U-U+-U-C-A+C-G-G-C-G-G-U-A-A-C-A-G, is homologous to that of the Escherichia coli tRNAGlu2 from residues 27 to 50, including the anticodon region and the variable loop, except that the E. coli tRNA has 5-methylaminomethyl-2-thiouridine instead of the selenonucleoside. 相似文献
17.
Winnie K. W. So Judy Y. W. Chan Bernard M. H. Law Kai Chow Choi Jessica Y. L. Ching Kam Leung Chan Raymond S. Y. Tang Carmen W. H. Chan Justin C. Y. Wu Stephen K. W. Tsui 《Nutrients》2021,13(2)
Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended. 相似文献
18.
Gabriela E. Leghi Merryn J. Netting Ching T. Lai Ardra Narayanan Michael Dymock Alethea Rea Mary E. Wlodek Donna T. Geddes Beverly S. Muhlhausler 《Nutrients》2021,13(6)
Maternal diet has the potential to affect human milk (HM) composition, but very few studies have directly assessed the effect of maternal diets on HM composition. The primary aim of this study was to assess the effect of improving dietary quality in lactating women over 2 weeks on the concentrations of macronutrients and metabolic hormones in HM. The secondary aims were to assess the impact of the dietary intervention on 24 h milk production, maternal body composition and infant growth. Fifteen women completed a 1-week baseline period followed by a 2-week dietary intervention phase targeted towards reducing fat and sugar intake. Maternal anthropometric and body composition and infant growth measurements were performed weekly. Total 24 h milk production was measured before and after the dietary intervention, and HM samples were collected daily. Maternal intakes of energy (−33%), carbohydrate (−22%), sugar (−29%), fat (−54%) and saturated fat (−63%) were significantly reduced during the dietary intervention. HM insulin, leptin and adiponectin concentrations were 10–25% lower at the end of the dietary intervention, but HM concentrations of macronutrients were unaffected. Maternal body weight (−1.8%) and fat mass (−6.3%) were significantly reduced at the end of the dietary intervention, but there were no effects on 24 h milk production or infant growth. These results suggest that reducing maternal energy, carbohydrate, fat and sugar intake over a 2-week period is associated with significant reductions in HM insulin, leptin and adiponectin concentrations. These changes may be secondary to decreases in maternal weight and fat mass. The limited studies to date that have investigated the association between metabolic hormone concentrations in HM and infant growth raise the possibility that the changes in HM composition observed in the current study could impact infant growth and adiposity, but further studies are required to confirm this hypothesis. 相似文献
19.
Ching Shan Wan Jade Mitchell Andrea B. Maier 《Journal of the American Medical Directors Association》2021,22(6):1331.e1-1331.e9
ObjectivesTo evaluate the effect of Hospital Admission Risk Program (HARP) on unplanned hospitalization, bed days, and mortality of enrolled individuals and to evaluate the cost-effectiveness of HARP.DesignA retrospective longitudinal analysis of hospital administrative data.InterventionIndividuals at risk of hospitalization were provided with multidisciplinary, community-based care support managed by care coordinators including integrated care planning, education, monitoring, service linkages, and general practitioner liaison over 6-9 months.Setting and ParticipantsIndividuals who were enrolled into 1 of 8 HARP chronic disease management programs between July 1, 2017, and June 30, 2018, at the Royal Melbourne Hospital, Australia.MethodsHospital admissions between 18 months before and 18 months after HARP enrollment were analyzed. Total hospital costs were compared between 18 months before and 12 months after HARP enrollment.ResultsA total of 1553 individuals with a median age of 71 years (interquartile range 60-81), 63.4% males, were admitted to HARP. Both unplanned hospitalizations and bed days were reduced during the HARP intervention compared to within 3 months before enrollment in each of the HARP management programs. After the HARP intervention, cardiac coach, cardiac heart failure, chronic respiratory, diabetes comanagement, and medication management programs had higher hospitalizations and bed days than individuals’ baseline of at least 3 months before HARP enrollment. Individuals in cardiac heart failure and chronic respiratory management programs had a higher mortality rate than other HARP chronic disease management programs. Individuals in cardiac coach, diabetes comanagement, and medication management programs had lower hospital costs during the HARP intervention compared to within 3 months before HARP enrollment.Conclusions and ImplicationsHARP reduced unplanned hospitalization and bed days but did not return individuals’ hospital use to baseline before the intervention. The variations in mortality between HARP chronic disease management programs implies that condition-specific goals between programs is preferable. 相似文献
20.
Johnson Bryan A. Lindgren Bruce R. Blaes Anne H. Parsons Helen M. LaRocca Christopher J. Farah Ronda Hui Jane Yuet Ching 《Annals of surgical oncology》2021,28(10):5668-5676
Annals of Surgical Oncology - Telemedicine was adopted to minimize exposure risks for patients and staff during the coronavirus disease 2019 pandemic. This study measured patient satisfaction and... 相似文献