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101.
H Y Lam J H K Chen K H Wong K Chan P Li M P Lee D N Tsang K Y Yuen W C Yam 《Journal of clinical virology》2007,38(1):39-43
BACKGROUND: Monitoring anti-retroviral therapy requires that viral load assays for human immunodeficiency virus type 1 (HIV-1) be applicable to diverse HIV-1 subtypes. OBJECTIVES: To evaluate NucliSens EasyQ HIV-1 assay for quantitation of common HIV-1 subtypes prevalent in South-east Asia. STUDY DESIGN: One hundred and nineteen plasma samples collected in Hong Kong and Cambodia were used to compare the performance of NucliSens EasyQ HIV-1 and COBAS Amplicor HIV-1 Monitor version 1.5 assays. Viral RNA extracted from the NucliSens MiniMAG was also used for HIV-1 subtyping. RESULTS: Performance of NucliSens EasyQ correlated well with COBAS Amplicor (r=0.777, p<0.001) and the small mean difference (0.0462log(10)IU/mL) obtained in the Bland and Altman model indicated good agreement between two assays. The NucliSens EasyQ assay demonstrated a 95% sensitivity at 500IU/mL and 100% specificity. Reproducibility of this assay was within log(10)2-4IU/mL and had a coefficient of variation between 2.3% and 10.4%. Among the 109 specimens included in the analysis, HIV-1 subtyping identified 64 CRF01_AE, 38 subtype B, 3 subtype C, 3 CRF07_BC and 1 subtype G viruses. CONCLUSIONS: Performance of NucliSens EasyQ was comparable to COBAS Amplicor for HIV-1 viral load monitoring. RNA extracts from NucliSens MiniMAG could be used for HIV-1 viral load monitoring, subtyping and drug resistance mutations detection. Our findings highlight the versatility of both NucliSens EasyQ and COBAS Amplicor in monitoring prevalent subtypes and rare circulating recombinant forms (CRFs) in the South-east Asia region. 相似文献
102.
Restriction of Epstein-Barr virus-specific cytotoxic T cells by HLA-A, -B, and -C molecules 总被引:5,自引:0,他引:5
HLA-loss variants of an Epstein-Barr virus-transformed B-lymphoblastoid cell line (EBV-LCL) 721 were used as target cells to identify HLA molecules utilized by EBV-LCL-specific cytotoxic T cells. Split culture analysis of cytotoxic T cells plated at limiting dilution showed killing of HLA-loss variants bearing either HLA-A2 or -B5 molecules, with 10 times higher frequency of cytotoxic T cells restricted by the HLA-B5 molecule. Clonal analysis confirmed the restriction by HLA-A2 or -B5 of some cytotoxic T-cell clones and identified cytotoxic T-cell clones cytolytic for target cells which do not express HLA-A or -B but do express the HLA-C determinant. Thus, our results show immunodominance of the HLA-B5 restriction determinant for EBV-induced antigens in the donor of the HLA-loss variants and provide evidence that the HLA-C molecule can also serve as restriction determinant for EBV-LCL-specific cytotoxic T cells. 相似文献
103.
P. J. Goodfellow H. A. Nevanlinna P. Gorman D. Sheer G. Lam P. N. Goodfellow 《Annals of human genetics》1989,53(1):15-22
A cDNA corresponding to the β-subunit of the human fibronectin receptor (β-FNR) was used as a probe in Southern blot analysis of mouse/human somatic cell hybrid DNAs and in in situ hybridization to metaphase chrmosomes. The β-FNR cDNA detects sequences prosent on parent of the somatic cell hybrids. In situ hybridization refined the localization of human sequences reacting with the β-FNR cDNA to 10p11.2. The A-1A5 monoclonal antibody which recognizes the beta-subunit of the fibronectin receptor on the cell surface was used to confirm that the sequences present on chromosome 10 correspond to those required for expression of β-FNR. 相似文献
104.
Hematopoietic cytokines such as interleukin (IL)-3, IL-5, and granulocyte macrophage colony-stimulating factor (GM-CSF) play a fundamental role in eosinophil functions in allergic asthma. The intracellular signal transduction mechanisms of these cytokines regulating the activation of eosinophils have been potential therapeutic targets. We investigated the roles of p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-kappaB) in IL-3, IL-5, and GM-CSF-induced adhesion, morphological changes, and subsequence transmigration of human eosinophils. IL-3, IL-5, and GM-CSF could augment the phosphorylation of p38 MAPK and nucleus translocation of NF-kappaB in eosinophils. cDNA expression arrays demonstrated that the gene expression levels of several adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), alpha6, beta2 integrin (CD18), and CD44 were upregulated by these cytokines. Results from functional assays showed that adhesion of eosinophils onto airway epithelial cells was enhanced after IL-3 and IL-5 but not GM-CSF stimulation. These cytokines could markedly induce shape change and augment the transmigration of eosinophils. Moreover, administration of either p38 MAPK inhibitor, SB 203580, or proteasome inhibitor, N-cbz-Leu-Leu-leucinal (MG-132), could inhibit the cytokine-induced adhesion, shape change, and transmigration of eosinophils. Together, our findings suggest that IL-3, IL-5, and GM-CSF regulated the adhesion and chemotaxis of human eosinophils through shared signaling pathways involving both p38 MAPK and NF-kappaB. Our results therefore shed light on the further development of more effective agents for allergic and inflammatory diseases. 相似文献
105.
106.
Ramaseshan R Kohli KS Zhang TJ Lam T Norlinger B Hallil A Islam M 《Physics in medicine and biology》2004,49(17):4031-4048
The commercially available microMOSFET dosimeter was characterized for its dosimetric properties in radiotherapy treatments. The MOSFET exhibited excellent correlation with the dose and was linear in the range of 5-500 cGy. No measurable effect in response was observed in the temperature range of 20-40 degrees C. No significant change in response was observed by changing the dose rate between 100 and 600 monitor units (MU) min(-1) or change in the dose per pulse. A 3% post-irradiation fading was observed within the first 5 h of exposure and thereafter it remained stable up to 60 h. A uniform energy response was observed in the therapy range between 4 MV and 18 MV. However, below 0.6 MeV (Cs-132), the MOSFET response increased with the decrease in energy. The MOSFET also had a uniform dose response in 6-20 MeV electron beams. The directional dependence of MOSFET was within +/-2% for all the energies studied. The inherent build-up of the MOSFET was evaluated dosimetrically and found to have varying water equivalent thickness, depending on the energy and the side of the beam entry. At depth, a single calibration factor obtained by averaging the MOSFET response over different field sizes, energies, orientation and depths reproduced the ion chamber measured dose to within 5%. The stereotactic and the penumbral measurements demonstrated that the MOSFET could be used in a high gradient field such as IMRT. The study showed that the microMOSFET dosimeter could be used as an in vivo dosimeter to verify the dose delivery to the patient to within +/-5%. 相似文献
107.
Priyanka Sharma Guojun Wu Deeptha Kumaraswamy Natalie Burchat Hong Ye Yongjia Gong Liping Zhao Yan Y. Lam Harini Sampath 《Nutrients》2021,13(2)
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies. 相似文献
108.
Energy drinks containing significant quantities of caffeine, taurine and sugar are increasingly consumed, particularly by adolescents and young adults. The putative effects of chronic ingestion of either standard energy drink, MotherTM (ED), or its sugar-free formulation (sfED) on metabolic syndrome were determined in wild-type C57BL/6J mice, in comparison to a soft drink, Coca-Cola (SD), a Western-styled diet enriched in saturated fatty acids (SFA), and a combination of SFA + ED. Following 13 weeks of intervention, mice treated with ED were hyperglycaemic and hypertriglyceridaemic, indicating higher triglyceride glucose index, which was similar to the mice maintained on SD. Surprisingly, the mice maintained on sfED also showed signs of insulin resistance with hyperglycaemia, hypertriglyceridaemia, and greater triglyceride glucose index, comparable to the ED group mice. In addition, the ED mice had greater adiposity primarily due to the increase in white adipose tissue, although the body weight was comparable to the control mice receiving only water. The mice maintained on SFA diet exhibited significantly greater weight gain, body fat, cholesterol and insulin, whilst blood glucose and triglyceride concentrations remained comparable to the control mice. Collectively, these data suggest that the consumption of both standard and sugar-free forms of energy drinks induces metabolic syndrome, particularly insulin resistance. 相似文献
109.
The European Journal of Health Economics - Social support is increasingly acknowledged as an important resource for promoting well-being. We test whether social support changes around retirement.... 相似文献
110.