海藻酸盐的理化特性及其在组织工程研究和临床中的应用

目的:对藻酸钠和藻酸钙的理化特性及在骨、软骨组织工程研究和临床中的应用作一系统回顾。资料来源:检索2000/2006 Medline与藻酸钠或藻酸钙相关的文献,检索词"sodium alginate,Calcium alginate",并限定文章语言种类为"English";同时检索中国医院数字图书馆1994/2006中国医学核心期刊关于藻酸钠或藻酸钙的相关文献,检索词"藻酸钠,藻酸钙",限定文章语言种类为中文。同时手工检索相关书籍。资料选择:对检索到的与藻酸钠或藻酸钙相关文献212篇进行筛选,并排除综述类文献,符合纳入标准的有71篇。资料提炼:对71篇文献进行分类整理,排除重复性文献,纳入33篇文献,其中22篇关于海藻酸理化特性,11篇为临床应用。资料综合:①藻酸钠水溶液在钙离子的作用下发生侧向交联由液态变为凝胶态,该水凝胶具有很好的亲水性,营养物质易于渗透扩散,其酶解产物对人体无毒害作用。这类凝胶以其良好的生物相容性在骨或软骨组织工程中、在药物缓释系统、创伤修复、治疗返流性食管炎等临床过程和改善水质、净化环境等方面发挥重要作用。②藻酸钙凝胶是藻酸钠的置换物,是一种中性偏碱的基质材料,除机械强度较差外,它在生物相容性、可降解性、细胞-材料界面、三维立体多孔结构和可塑性等方面都有利于种子细胞的接种和生长,是理想的组织工程基质材料,尤其在骨和软骨组织工程中。结论:海藻酸盐主要从海藻中提取,其凝胶具有良好的生物相容性,在组织工程及临床应用方面有巨大的潜力。     

Frequency of platelet-specific antigens among Chinese in Taiwan

The frequencies of six platelet-specific antigens among Chinese in Taiwan are reported, which have not previously been well studied. HPA- 1a (PlA1) antigen was positive in all 1100 Chinese tested. HPA-4b (Yukb) antigen was positive in all 100 persons tested. HPA-2b (Ko(a), Sib(a)) antigen was positive in 9 percent of 100 persons tested, HPA-3a (Bak(a)) in 77 percent, and NAKa in 96 percent. HPA-4a (Yuk(a)) antigen occurred in 0 percent in this study but is estimated to be present in 0.5 percent of the Taiwanese population.     

The Medical Bookman

This article was written by Dr. Frederick R. Taylor, friend and physician to Dr. White. Dr. Taylor is part-time Professor of Medical Literature and Associate Professor of Clinical Medicine at Bowman-Gray School of Medicine, Winston-Salem, North Carolina.     

Smokers With Behavioral Health Comorbidity Should Be Designated a Tobacco Use Disparity Group

Smokers with co-occurring mental illness or substance use disorders are not designated a disparity group or priority population by most national public health and tobacco control groups.These smokers fulfill the criteria commonly used to identify groups that merit special attention: targeted marketing by the tobacco industry, high smoking prevalence rates, heavy economic and health burdens from tobacco, limited access to treatment, and longer durations of smoking with less cessation. A national effort to increase surveillance, research, and treatment is needed.Designating smokers with behavioral health comorbidity a priority group will bring much-needed attention and resources. The disparity in smoking rates among persons with behavioral health issues relative to the general population will worsen over time if their needs remain unaddressed.ELIMINATING DISPARITIES IN health and health care is a major priority in the United States.1,2 Groups with health disparities are referred to as vulnerable or priority populations and can be defined by factors such as race/ethnicity, socioeconomic status, geography, gender, age, disability status, or sexual orientation.3 The sources of these disparities are complex, rooted in historic and social inequities.4 Cigarette smoking, the leading cause of preventable death, is listed as one of 21 conditions with ongoing health disparities that must be addressed.1 Indeed, as the American Legacy Foundation points out, tobacco is not an equal opportunity killer.5 The criteria organizations such as the Centers for Disease Control and Prevention use to designate a tobacco disparity group are that they experience disproportionate tobacco consumption, disproportionate consequences or health burden from tobacco use, disproportionate economic burden from tobacco use, or limited access to tobacco-related health care.1,6,7 These groups may also be targeted by the tobacco industry with special marketing.6 Increased tobacco consumption may stem from differences in risk for tobacco use initiation or progression, differences in tobacco use prevalence and rates of nicotine dependence, and differences in smoking cessation rates.Smokers with a co-occurring mental illness or substance use disorder (SUD) have historically been underserved.8–13 Persons with behavioral health conditions, a collective term whose use is increasing because it may reduce stigma, compose a significant subset of smokers in the United States. A recent study found that cigarette smoking prevalence was 37.8% among people with any anxiety disorder, 45.1% among those with any affective disorder, 63.6% among those with a substance use disorder, and only 21.3% among those with no mental disorder.14 Smoking rates have plateaued despite ongoing tobacco control efforts, and clinical data support the concern that public health techniques that have been largely successful in the past may have reduced impact with remaining smokers.15,16 Although population-level data are less consistent on this point, data from both the National Health Interview Survey17 and the National Survey of Drug Use and Health18 suggest that smokers with moderate to high levels of general psychological distress are less likely than those with lower levels to have quit smoking. These data raise the possibility that behavioral health comorbidity may contribute to existing concerns about the impact of current tobacco approaches on today’s smokers.Surprisingly, most tobacco control Web sites and organizations, such as the Centers for Disease Control and Prevention’s Office on Smoking and Health,19 Healthy People 2020,2 and the American Legacy Foundation,20 do not designate smokers with behavioral health comorbidity as a disparity group or priority population. Understanding and eliminating disparities are such high priorities that these larger organizations have sponsored dedicated spin-off groups, such the National Networks for Tobacco Control and Prevention (sponsored by the Centers for Disease Control and Prevention)21 and the Tobacco Research Network on Disparities (TReND; cosponsored by the National Cancer Institute and American Legacy Foundation).22 These groups have paid only cursory attention to smokers with behavioral health comorbidity.23 For example, these smokers are included on the TReND Web site with a long list of “other historically underserved groups” that includes lesbian, gay, bisexual, and transgender persons; people with disabilities; and the military. (Major tobacco control groups in the United States and their identified disparity populations are listed in

Evaluating Provider Advice and Women’s Beliefs on Total Weight Gain During Pregnancy

Excessive gestational weight gain (GWG) is associated with complications for both mother and child. Minority women are at increased risk for excessive GWG, yet are underrepresented in published weight control interventions. To inform future interventions, we examined the prevalence and accuracy of provider advice and its association with personal beliefs about necessary maternal weight gain among predominantly Latina pregnant women. Secondary analysis examining baseline data (N = 123) from a healthy lifestyle randomized controlled trial conducted in and urban area of the South East. Only 23.6 % of women reported being told how much weight to gain during pregnancy; although 58.6 % received advice that met Institute of Medicine recommendations. Concordance of mothers’ personal weight gain target with clinical recommendations varied by mothers’ pre-pregnancy weight status [χ ₍₄₎ ²  = 9.781, p = 0.044]. Findings suggest the need for prenatal providers of low-income, minority women to engage patients in shaping healthy weight gain targets as a precursor to preventing excessive GWG and its complications.     

Genetic risk score does not correlate with body mass index of Latina women in a clinical trial

Obesity disproportionately affects Latina women. Common genetic variants are convincingly associated with body mass index (BMI) and may be used to create genetic risk scores (GRS) for obesity that could define genetically influenced forms of obesity and alter response to clinical trial interventions. The objective of this study was (1) to identify the frequency and effect size of common obesity genetic variants in Latina women; (2) to determine the clinical utility of a GRS for obesity with Latina women participating in a community-based clinical trial. DNA from 85 Latina women was genotyped for eight genetic variants previously associated with BMI in Caucasians, but not yet assessed in Latina populations. The main outcome measure was the correlation of GRS (sum of eight risk alleles) with BMI, waist circumference, and percent body fat. A majority (83%) of participants had a BMI ≥25. Frequency of loci near FTO, MC4R, and GNPDA2 were lower in Latinas than Caucasians. Association of each locus with BMI was lower in Latinas compared to Caucasians with no significant correlations with BMI. We conclude that an eight locus GRS has no clinical utility for explaining obesity or predicting response to intervention in Latina women participating in a clinical trial.     

Association between antidepressant drug use during pregnancy and child healthcare utilisation

Objective  To evaluate healthcare utilisation by children who were exposed to antidepressant drug use during pregnancy and those whose mothers stopped using antidepressants before pregnancy compared with a control group.
Design  Cohort study.
Setting  Health insurance records in the Netherlands.
Population  A total of 38 602 children born between 2000 and 2005.
Methods  Survey of child healthcare utilisation in relation to gestational antidepressant use.
Main outcome measure  Healthcare utilisation rates during the first year of life, with special emphasis to medical care related to cardiac disease.
Results  Children of mothers who used antidepressants during pregnancy showed increased healthcare use during the first year of life, independent of the mother's healthcare use. The relative risk of more than two visits to general practitioners was 1.5 (95% confidence interval, CI: 1.3–1.8) in the continuous antidepressant users group and 1.3 (95% CI: 1.2–1.5) in the group of children whose mothers stopped taking medication. In both study groups there was a trend towards more drug use for infections and inflammation compared with the control group. Children continuously exposed to antidepressants had an increased risk of cardiac interventions such as cardiovascular surgery or heart catheterisation, relative risk of 5.6 (95% CI: 1.8–17.4). The risk of physiotherapy was twice as high in the antidepressant group compared with the control group (relative risk 2.0; 95% CI: 1.5–2.6).
Conclusion  Antidepressant use during pregnancy is associated with increased child healthcare utilisation and increased risk of major cardiac interventions in early childhood.     

Pituitary adenomas in patients with Cushing disease: initial experience with Gd-DTPA-enhanced MR imaging

To assess the role of magnetic resonance imaging in the evaluation of adrenocorticotropic-hormone (ACTH)-producing pituitary adenomas, and the effect of intravenously administered gadolinium-diethylenetriaminepentaacetic acid (DTPA) on lesion/pituitary contrast, imaging was performed in 13 patients with clinical and chemical evidence of Cushing disease. Images were obtained at 0.5 T before and after the injection of Gd-DTPA (0.1 mmol/kg). Lesions were identified in eight of 12 precontrast and ten of 12 postcontrast studies. In these 12 patients adenomas were found at transsphenoidal surgery. The other patient, with normal images, was found to have an ectopic source of ACTH. Coronal images corresponded remarkably well with the neurosurgeon's intraoperative findings. Serial T1-weighted images disclosed early enhancement of the pituitary gland and delayed enhancement of the cystic adenomas. The discrepancy in times to peak enhancement accounted for improved lesion/pituitary contrast in some early images and for reversal or diminution of lesion/pituitary contrast in later images.     

Binding characteristics of ortho-toluidine to rat hemoglobin and albumin

The binding characteristics of [14C]ortho-toluidine (OT), a suspect human carcinogen, were investigated in male Sprague-Dawley rats. Rats were administered [14C]OT i.p. at 10, 20, 40, 50, or 100 mg/kg body weight, then sacrificed at 2, 4, 8, 18, 24, 48, or 72 h, or 7, 14, or 28 days. Hemoglobin (Hb) and albumin (Alb) were isolated from blood, and OT binding was determined by liquid scintillation counting. For Alb, peak binding occurred at 50 mg/kg at the 4-h time point (15.6 ng OT/mg Alb), while for Hb peak binding was observed at 24 h at the 100 mg/kg dose (23.0 +/- 5.1 ng OT/mg Hb). OT-Alb binding was not linear; however, OT-Hb binding appeared to increase linearly in a dose-dependent manner. Biological half-lives of OT bound to Alb or Hb were observed to be 2.6 and 12.3 days, respectively, after rats were administered a single dose of [14C]OT and sacrificed after 4 h to 28 days. The effect of route of administration on OT-Hb adduct formation was investigated, and approximately a two-fold increase in radioactivity bound to Hb was observed after i.p. administration of 100 mg/kg [14C]OT versus oral intubation. Additional studies were carried out to investigate the effect of microsomal enzyme induction. An increase in OT-Hb binding was seen in rats pretreated with phenobarbital compared to rats pretreated with beta-naphthoflavone or without pretreatment; however, this increase was not statistically significant. These results suggest that OT-Hb and OT-Alb adduct formation may be a valuable biomarker for assessing workplace exposure.