血管紧张素原基因5’端启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性

目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014～1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087～7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。     

Detection of Cyclospora cayetanensis oocysts in human fecal specimens by flow cytometry

A diagnosis of cyclosporiasis typically involves stool examinations for the presence of Cyclospora oocysts by means of microscopy. In recent years, flow cytometry has been gaining in popularity as a novel method of detecting pathogens in environmental and clinical samples. The present study is an evaluation of a flow cytometric method for the detection and enumeration of Cyclospora oocysts in human fecal specimens associated with food-borne outbreaks of cyclosporiasis in Ontario, Canada. Flow cytometry results were generally very comparable to the original microscopy results for these specimens, in terms of both presence or absence of oocysts and relative oocyst concentrations. Of the 34 fecal specimens confirmed positive for Cyclospora by microscopy, 32 were also found positive by flow cytometry, and 2 others were considered equivocal. Of the eight fecal specimens reported to be negative by microscopy, two were found positive by flow cytometry and five others were considered equivocal. These two flow cytometry-positive samples and one of the equivocal samples were confirmed by microscopic reexamination, suggesting that flow cytometry may be more sensitive than microscopy. While the sample preparation time for flow cytometry is similar to or slightly longer than that for microscopy, the actual analysis time is much shorter. Further, because flow cytometry is largely automated, an analyst's levels of fatigue and expertise will not influence results. Flow cytometry appears to be a useful alternative to microscopy for the screening of large numbers of stool specimens for Cyclospora oocysts, such as in an outbreak situation.     

Seroprevalence of hepatitis B and C viruses in moderate and severe COVID-19 inpatients: A cross-sectional study at a referral center in Mexico

Introduction and ObjectivesThe emergence of SARS-CoV-2, which causes the coronavirus disease (COVID-19) has caused a great impact on healthcare systems worldwide, including hepatitis B and C viruses screening and elimination programs. The high number of COVID-19 hospitalizations represent a great opportunity to screen patients for hepatitis B virus (HBV) and hepatitis C virus (HCV), which was the aim of this study.Material and MethodsCross-sectional, retrospective study performed between April 2020 and 20201 at a referral center in Mexico dedicated to the care of adults with severe/critical COVID-19. We retrieved clinical, demographic, and laboratory results from each patient´s medical records, including antibodies against HCV (anti-HCV), HBV surface antigen (HBsAg), antibodies against the HBV core antigen (anti-HBcAg), and antibodies against HBsAg (anti-HBsAg).ResultsOut of 3620 patients that were admitted to the hospital, 24 (0.66%), 4 (0.11%), and 72 (1.99%) tested positive for anti-HCV, HBsAg, and anti-HBcAg, respectively. Of all seronegative patients, 954 (27%) had undetectable anti-HBsAg and 401 (12%) had anti-HBsAg at protective levels. Blood transfusion was the most relevant risk factor. Only 9.7% of the anti-HBc positive, 25% of the HBsAg positive, and 52% of the anti-HCV positive were aware of their serological status.ConclusionsIn this study we found a prevalence of anti-HCV of 0.66%, HBsAg in 0.11%, and isolated anti-HBcAg in 1.99%. We also found that HBV vaccination coverage has been suboptimal and needs to be reinforced. This study gave us a trustworthy insight of the actual seroprevalence in Mexico, which can help provide feedback to the Hepatitis National Elimination Plan.     

Caudal-posteroanterior view in coronary arteriography

Posteroanterior (PA) and caudally angulated PA views were obtained in 20 patients undergoing routine coronary arteriography. Although the left main coronary artery (LMCA) was seen well on both views in all patients, the PA-caudal view improved depiction of the LMCA bifurcation in 15 (75%). In addition, the PA-caudal view markedly improved depiction of the circumflex artery, affording optimal depiction of this artery and its branches in 78%-89% of patients. Neither the PA nor the PA-caudal view allowed adequate depiction of the left anterior descending artery. Thus, the PA-caudal view should supplant the PA view in routine coronary arteriography.     

Yeast arginine permease: nucleotide sequence of the CAN1 gene

Summary The yeast CAN1 gene, thought to encode arginine permease, has found use in genetics as a selectable locus. We have sequenced the cloned CAN1 gene, which contains an open reading frame of 1770 nucleotides, encoding a polypeptide of calculated molecular weight 65,766. Disruption of this open reading frame largely abolishes CAN1 gene expression, while subcloned fragments of the open reading frame hybridize strand —specifically to a 2.3 kb yeast RNA message. The encoded protein has no leader signal sequence, and is highly hydrophobic, with a possible twelve membrane-spanning domains, several of which have the high hydrophobic moments seen in channel-forming or permease proteins. This protein structure is consistent with the CAN1 product being the plasma membrane arginine permease.     

Oral anticoagulation: challenges in the case-management setting

By understanding barriers, providing education, and advocating appropriate treatment, case managers play an essential role in the prevention and treatment of thromboembolic disorders. Yet, thromboembolic events such as stroke and deep-vein thrombosis still result in substantial morbidity and mortality despite the availability of effective prophylactic anticoagulation therapy. Although oral warfarin, because of its established efficacy, remains the mainstay in the prevention and treatment of thromboembolic disorders associated with atrial fibrillation, a common antecedent, it is fraught with enduring impediments that hinder effectiveness, safety, and use. With a narrow therapeutic widow, optimal treatment relies on maintaining a tight international normalized ratio (INR) range, usually between 2.0 and 3.0. Lacking intensive anticoagulation clinic monitoring, patients are often outside the therapeutic range, compromising efficacy or safety. Furthermore, the need for frequent and demanding INR monitoring, a slow onset of action, and an elevated risk for drug-drug and food-drug interactions conspire to undermine the use of warfarin, especially in high-risk groups, such as the elderly. Unquestionably, well-tolerated, convenient, and effective alternatives to oral warfarin are needed to improve the management of patients in need of anticoagulation therapy. Several new oral anticoagulants are in development, but only one, ximelagatran, has completed Phase-III development and awaits Food and Drug Administration (FDA) approval. An oral direct thrombin inhibitor, ximelagatran, appears to offer a profile quite different from warfarin: a wide therapeutic window that obviates routine drug-level monitoring and twice-daily oral administration with minimal drug interactions; however, transient liver enzyme elevations remain an unresolved issue. As case managers typically work with those who present with clinical or psychosocial challenges, or both, this treatment approach may provide an alternative that would enhance patient outcomes.     

Quantitation of antibody to Candida mannan by enzyme-linked immunosorbent assay

Early clinical diagnosis of invasive candidiasis is difficult. To facilitate rapid diagnosis of Candida infections, we developed an ELISA to quantitate levels of antibody to Candida mannan. The test was standardized by analysis of a nonselected inpatient population to determine a cutoff point defining the upper 5% of such a population as test-positive. Passively acquired sera from patients in intensive care units, patients with neoplastic disease or recent renal allografts, and other patients were analyzed. There was no significant difference between the number of positive tests obtained from patients in whom candidiasis was considered but cultures were negative and from the nonselected inpatient population. Positive tests were obtained from 18.5% of patients with Candida mucocutaneous colonization or infection and 40% and 63.6% of patients with probable and proven invasive candidiasis, respectively. Patients with neoplastic disease had lower test sensitivity than patients in other test categories. These results demonstrate the usefulness of a simple, rapid, standardized test for quantitation of levels of antibody activity to Candida mannan in the serodiagnosis of candidiasis.     

A non-invasive technique for assessing innominate bone motion

OBJECTIVE: To determine the suitability of a magnetic tracking device to measure pelvic bone range of motion based on palpated and digitized pelvic landmarks. DESIGN: A repeated measures study was conducted in two experiments to determine the reliability and validity of innominate bone range of motion measured with a magnetic tracking device in healthy subjects through passive hip abduction and external rotation. BACKGROUND: Because of the anatomical position of the pelvic joints, kinematic analysis of joint motion is difficult. Accurate and precise measurements typically require highly invasive techniques involving implantation of titanium markers and exposing the subject to multiple radiographs. There is a need for a practical and accurate measurement method that will allow researchers and clinicians to accurately and reliably evaluate motion in the pelvis. METHODS: Innominate bone angles were measured for two static hip postures from the 3D spatial coordinates of the pelvic landmarks. By palpating and subsequently digitizing pelvic landmarks using an electro-magnetic tracking device the 3D coordinates were obtained. Palpated results were validated using CT scans and a metallic bead attached to the palpated landmarks. RESULTS: The mean range of innominate bone motion was between 3 degrees and 4 degrees (transverse plane) for each side with large variability across the subjects in the range of motion. Despite this variability, the measurements were found to be reliable and valid.     

低血糖指数膳食改善超重老年糖尿病患者氧化应激水平

目的:观察低血糖指数的膳食对2型糖尿病患者氧化应激状态的影响。方法:2004-10/11在上海市静安区二个社区卫生服务中心招募受试者,经医生明确诊断为2型糖尿病、病程超过6个月,体质量指数≥24kg/m2的老年糖尿病志愿者43名,受试者对试验知情同意。采用随机交叉试验随机分配至低血糖指数饮食组和高血糖指数饮食组,每种膳食分别连续使用4周,间隔洗脱期4周,比较试验前后患者超氧化物歧化酶、脂质过氧化产物丙二醛和谷胱甘肽过氧化物酶含量的变化。结果:受试者依从性好,除1人因试验期间发现肿瘤而退出试验,42名志愿者按设计要求完成试验。膳食干预后低血糖指数饮食组和高血糖指数饮食组的超氧化物歧化酶活力分别升高了15.68%和21.33%,丙二醛水平分别下降23.94%和21.55%,谷胱甘肽过氧化物酶活力分别升高了15.74%和17.09%;干预后低血糖指数饮食组丙二醛下降水平与高血糖指数饮食组比较差异有显著性意义(P<0.05),而超氧化物歧化酶和谷胱甘肽过氧化物酶活性两组间差异无显著性意义(P>0.05)。结论:在控制总能量的基础上给予平衡膳食能够改善其氧化应激水平,采用低血糖指数食物有助于氧化应激水平的改善。