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71.

Summary

This cross-sectional study showed that peak bone mineral density in Vietnamese women is comparable to that in Caucasian women; however, the prevalence of osteoporosis in post-menopausal Vietnamese women was slightly higher than in Caucasian women. The age of achieving peak bone mass in Vietnamese women was between 26 and 30 years.

Introduction

While peak bone mass and its determinants have been well-documented in Caucasian populations, little has been studied in Asian populations. The present study was designed to estimate the peak bone mineral density (BMD), age of its attainment, and to examine the prevalence of osteoporosis in Vietnamese women aged 50+.

Methods

The study was designed as a cross-sectional study with 328 women aged between 10 and 65 years (average age: 41) who were randomly selected from two districts around Hanoi city according to a stratified sampling scheme. BMD at the lumbar spine, femoral neck and total hip was measured by a DXA instrument (GE Lunar Prodigy, WI, USA). BMD was modeled as a cubic function of age, from which peak BMD and age at peak BMD were estimated. Bootstrap method was utilized to estimate the 95% confidence interval of peak BMD and age at peak BMD. From the peak BMD, T-score was calculated for each woman, and using the World Health Organization criteria, any woman with femoral neck BMD T-score ≤ -2.5 was classified as having osteoporosis.

Results

Peak BMD was estimated at 1.16 g/cm2 (standard deviation [SD]: 0.13 g/cm2) at the lumbar spine, 1.02 g/cm2 (SD 0.12) at the total hip, and 0.94 g/cm2 (SD 0.11) at the femoral neck. In the cubic polynomial model, the age at peak BMD was estimated to range between 27 and 29 years. The prevalence of osteoporosis among those aged between 50 and 65 years was 23%. This prevalence was higher than in Chinese, Japanese, Korean and Caucasian populations.

Conclusion

These data suggest that although the peak BMD in Vietnamese women is comparable to, the prevalence of osteoporosis is higher than, in some other Asian and Caucasian women. It seems that osteoporosis is an important public health burden in Vietnam.  相似文献   
72.
Chitosan is a polysaccharide scaffold used to enhance cartilage repair during treatments involving bone marrow stimulation, and it is reported to increase angiogenesis and osteogenesis in vivo. Here, we tested the hypotheses that addition of chitosan particles to the media of human bone marrow stromal cell (BMSC) cultures stimulates osteogenesis by promoting osteoblastic differentiation and by favoring the release of angiogenic factors in vitro. Confluent BMSCs were cultured for 3 weeks with 16% fetal bovine serum, ascorbate-2-phosphate and disodium β-glycerol phosphate, in the absence or presence of dexamethasone, an anti-inflammatory glucocorticoid commonly used as an inducer of BMSC osteoblast differentiation in vitro. As expected, dexamethasone slowed cell division, stimulated alkaline phosphatase activity and enhanced matrix mineralization. Added chitosan particles accumulated intra- and extracellularly and, while not affecting most osteogenic features, they inhibited osteocalcin release to the media at day 14 and interfered with mineralized matrix deposition. Interestingly, dexamethasone promoted cell attachment and suppressed the release and activation of matrix metalloprotease-2 (MMP-2). While chitosan particles had no effect on the release of angiogenic factors, dexamethasone significantly inhibited (p < 0.05 to p < 0.0001) the release of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-α), interleukins 1β, 4, 6, and 10 (IL-1β, IL-4, IL-6, IL-10), and a host of other inflammatory factors that were constitutively secreted by BMSCs. These results demonstrate that chitosan particles alone are not sufficient to promote osteoblast differentiation of BMSCs in vitro, and suggest that chitosan promotes osteogenesis in vivo through indirect mechanisms. Our data further show that continuous addition of dexamethasone promotes osteoblastic differentiation in vitro partly by inhibiting gelatinase activity and by suppressing inflammatory cytokines which result in increased cell attachment and cell cycle exit.  相似文献   
73.
A paraprotein is a monoclonal immunoglobulin or light chain present in the blood or urine; it is produced by a clonal population of mature B cells, most commonly plasma cells. In individuals aged >50 years the incidence of a paraprotein is 3.2%. Plasma cell disorders can be considered as a spectrum of conditions ranging from monoclonal gammopathy of undetermined significance (MGUS), through asymptomatic, to symptomatic myeloma. MGUS is defined by a low level of paraprotein <30 g/l, bone marrow plasma cells <10% and the absence of myeloma related organ or tissue damage (predominantly renal, skeletal or bone marrow impairment.) MGUS requires no therapy and the overall risk of progression to myeloma is 1% per year. Myeloma remains incurable with a median survival of 3-4 years; autologous stem cell transplant can prolong survival, if appropriate. Thalidomide in combination with dexamethasone has an emerging role in the treatment of myeloma.  相似文献   
74.
Probiotics: sorting the evidence from the myths   总被引:1,自引:0,他引:1  
Probiotics consist of yeast or bacteria, especially lactic acid bacteria. They are available as capsules, powder, fermented milks or yoghurts. Probiotics exhibit strain-specific differences in their resistance to acid and bile, ability to colonise the gastrointestinal tract, clinical efficacy, and benefits to the health of the host. There is level I evidence for the use of probiotics in treating acute infectious diarrhoea and preventing antibiotic-associated diarrhoea, with Lactobacillus rhamnosus GG and Saccharomyces boulardii having the most evidence to support their use for these conditions. There is level II evidence that S. boulardii combined with high-dose vancomycin is more effective than the antibiotic alone in preventing recurrent Clostridium difficile diarrhoea. There is level I evidence that probiotics prevent traveller's diarrhoea. There is level I evidence for use of the high-potency probiotic VSL#3 in preventing pouchitis, and level II evidence for this agent in preventing relapse in patients with ulcerative colitis. Probiotics are generally regarded as safe and well tolerated. Some probiotics may be contraindicated in patients who are immunocompromised or have severe underlying illness, as they have been reported to cause fungaemia and bacteraemia.  相似文献   
75.
OBJECTIVE: To evaluate the safety and efficacy of 5% imiquimod cream for cutaneous dysplasia in high-risk renal transplant recipients. DESIGN: A randomized, blinded, placebo-controlled study comparing treated with control skin. SETTING: A specialist organ transplant dermatology clinic. PATIENTS: Twenty-one high-risk patients with skin cancer with comparable areas of clinically atypical skin on dorsal hands or forearms. INTERVENTIONS: Imiquimod or placebo (randomly assigned) applied 3 times a week for 16 weeks to 1 dorsal hand or forearm, with 8 months of follow-up. At week 16, biopsy samples were collected from pre-assigned sites in the treatment and control areas and were examined for dysplasia. MAIN OUTCOME MEASURES: The proportion of patients showing reduced numbers of viral and keratotic lesions and reduced histological severity of dysplasia in the treatment vs control areas at week 16, serum creatinine levels, and tumors developing in the study sites. RESULTS: Fourteen patients receiving imiquimod and 6 receiving placebo completed the study. Seven patients using imiquimod (1 taking placebo) had reduced skin atypia, 7 using imiquimod (none taking placebo) had reduced viral warts, and 5 using imiquimod (1 taking placebo) showed less dysplasia histologically. In 1 year, fewer squamous skin tumors arose in imiquimod-treated skin than in control areas. Renal function was not adversely affected. CONCLUSIONS: Topical 5% imiquimod cream seems to be safe on skin areas up to 60 cm2 in renal transplant recipients. It may be effective in reducing cutaneous dysplasia and the frequency of squamous tumors developing in high-risk patients. Larger studies are required to confirm these results.  相似文献   
76.
77.

BACKGROUND

Enhancing patient-centered care and shared decision making (SDM) has become a national priority as a means of engaging patients in their care, improving treatment adherence, and enhancing health outcomes. Relatively little is known about the healthcare experiences or shared decision making among racial/ethnic minorities who also identify as being LGBT. The purpose of this paper is to understand how race, sexual orientation and gender identity can simultaneously influence SDM among African-American LGBT persons, and to propose a model of SDM between such patients and their healthcare providers.

METHODS

We reviewed key constructs necessary for understanding SDM among African-American LGBT persons, which guided our systematic literature review. Eligible studies for the review included English-language studies of adults (≥ 19 y/o) in North America, with a focus on LGBT persons who were African-American/black (i.e., > 50 % of the study population) or included sub-analyses by sexual orientation/gender identity and race. We searched PubMed, CINAHL, ProQuest Dissertations & Theses, PsycINFO, and Scopus databases using MESH terms and keywords related to shared decision making, communication quality (e.g., trust, bias), African-Americans, and LGBT persons. Additional references were identified by manual reviews of peer-reviewed journals’ tables of contents and key papers’ references.

RESULTS

We identified 2298 abstracts, three of which met the inclusion criteria. Of the included studies, one was cross-sectional and two were qualitative; one study involved transgender women (91 % minorities, 65 % of whom were African-Americans), and two involved African-American men who have sex with men (MSM). All of the studies focused on HIV infection. Sexual orientation and gender identity were patient-reported factors that negatively impacted patient/provider relationships and SDM. Engaging in SDM helped some patients overcome normative beliefs about clinical encounters. In this paper, we present a conceptual model for understanding SDM in African-American LGBT persons, wherein multiple systems of social stratification (e.g., race, gender, sexual orientation) influence patient and provider perceptions, behaviors, and shared decision making.

DISCUSSION

Few studies exist that explore SDM among African-American LGBT persons, and no interventions were identified in our systematic review. Thus, we are unable to draw conclusions about the effect size of SDM among this population on health outcomes. Qualitative work suggests that race, sexual orientation and gender work collectively to enhance perceptions of discrimination and decrease SDM among African-American LGBT persons. More research is needed to obtain a comprehensive understanding of shared decision making and subsequent health outcomes among African-Americans along the entire spectrum of gender and sexual orientation.
  相似文献   
78.
79.
We are interested in the characterization of the effects of alcohol on human T-cell activation, maturation, and migration, because this cell population is crucial in the initiation, regulation, and propagation of cellular immunity. We and others have described the effects of both acute and chronic exposure of human immune cells to ethanol (EtOH) in vitro. Herein, we briefly, review these reports and expand this body of literature with the inclusion of new data recently obtained in our laboratory. We confirm the blunting effects of EtOH on the production of interleukin-2 and mitogen proliferative response following T-cell mitogen stimulation, and on the expression of membrane markers of activation. We show that EtOH significantly alters the expression of the CD4 cell-associated marker of activation, CD26. We report the effect of EtOH on the expression of the homing receptor CD62L by CD4+ cells, and on their ability to adhere by a CD18-mediated process to a defined cellular substratum. Furthermore, we demonstrate the effects of EtOH and EtOH and 0-endor-phin pretreatment on the activation of CD4+ lymphocytes endowed with the homing receptor CD62L.  相似文献   
80.
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