Potential capsule switching from serogroup Y to B: The characterization of three such Neisseria meningitidis isolates causing invasive meningococcal disease in Canada

Three group B Neisseria meningitidis isolates, recovered from meningococcal disease cases in Canada and typed as B:2c:P1.5, were characterized. Multilocus sequence typing showed that all three isolates were related because of an identical sequence type (ST) 573. Isolates typed as 2c:P1.5 are common in serogroup Y meningococci but rare in isolates from serogroups B or C. Although no serogroup Y isolates have been typed as ST-573, eight isolates showed five to six housekeeping gene alleles that were identical to that of ST-573. This suggested that the B:2c:P1.5 isolates may have originated from serogroup Y organisms, possibly by capsule switching.Key Words: Capsule switching, Neisseria meningitidis, Serogroup YNeisseria meningitidis is a significant pathogen that causes invasive meningococcal disease (IMD). The average case fatality rate of 9% to 12% remains high despite the availability of effective antibiotics and vaccines (1). Laboratory study and surveillance of N meningitidis involves the characterization of a number of surface markers of the bacterium, including its capsule and outer membrane proteins (OMPs). Most epidemiological studies of meningococcal disease rely on differentiating meningococcal isolates based on their serogroup, serotype and serosubtype. Serogrouping is determined by the demonstration of serologically distinct epitopes present on chemically and structurally different capsules. Serotyping and serosubtyping rely on the detection of distinct epitopes present on three of five different classes of OMPs of N meningitidis. Serotyping epitopes are found on the class 2 or class 3 OMP (also called PorB) of N meningitidis; these OMPs are expressed in a mutually exclusively manner (ie, a strain will only express either a class 2 or class 3 OMP but not both). Serosubtyping epitopes are present on the class 1 OMP (also called PorA). Based on this nomenclature scheme, a strain can therefore be characterized by its antigenic formula; for example, B:15:P1.7,16 refers to serogroup B, serotype 15 and serosubtype P1.7,16.One of the most important virulence factors of meningococci is the capsular polysaccharide antigen, which is also the basis for serogrouping and is the target antigen for the currently licensed vaccines against A, C, Y and W135 organisms. Of the 13 known serogroups, five (serogroups A, B, C, Y and W135) are responsible for most of the meningococcal disease worldwide (2). In North America, most endemic and epidemic strains belong to serogroups B, C, Y and W135 (3,4). Capsules of serogroups B, C, Y and W135 meningococci contain sialic acid, either as a homopolymer of sialic acids assembled by alpha-2,8 linkages (serogroup B) or alpha-2,9 linkages (serogroup C), or as a heteropolymer of sialic acids with glucose (serogroup Y) or galactose (serogroup W135). Besides demonstrating structural similarities, these four serogroups of meningococci also have very similar capsule polysaccharide synthesis (cps) gene loci (5). Because of this similarity, capsule switching has been demonstrated in vivo and in vitro by specific gene replacement within the cps loci between different serogroups. To date, a number of IMD cases have been described in the literature to be caused by organisms in which capsule switching between serogroup B and C meningococci occurred (6-8).In the present paper, the authors describe three unusual serogroup B meningococci isolated from separate IMD cases in Nanaimo, British Columbia, that presented with the OMP antigens 2c:P1.5, characteristic of serogroup Y strains found in Canada (4). This antigenic profile prompted the authors to examine the relationship of these three serogroup B strains with antigenically similar serogroup Y organisms isolated in Canada. The authors describe the characterization of these antigenically similar isolates and postulate that the B:2c:P1.5 isolates arose by capsule switching from serogroup Y organisms.     

肾移植术后肺炎淋巴细胞HLA-DR表达与复方清热颗粒的干预作用

目的:观察肾移植术后肺炎患者外周血淋巴细胞表面HLA-DR抗原表达的动态变化及中药复方清热颗粒的治疗效果。方法:选择2005-01/2006-02于北京友谊医院感染科就诊的肾移植术后肺炎患者32例,患者均知情同意。将32例患者按随机数字表法分为2组:①西医治疗组(n=18)单纯采用西医方法进行抗感染及免疫抑制等治疗。②中西医结合组(n=14)在上述基础上加用中药复方清热颗粒(由首创大地药业有限公司配制生产,主要成分为蒲公英30g,败酱草30g,生黄芪30g,大黄6g)口服治疗,1袋/次,3次/d,14d为1个疗程。分别于入院时、治疗7,14d后行血HLA-DR检测,以反映T细胞的活化状态。治疗14d后进行疗效评估:体温下降,呼吸道症状有所改善,X射线显示病灶有吸收为好转。结果:纳入肾移植术后肺炎患者32例,全部进入结果分析,无脱落。①两组患者治疗好转率比较:中西医结合组患者的治疗好转率高于西医治疗组,但差异无显著性意义(93%,78%,P>0.05)。②两组患者淋巴细胞表面HLA-DR抗原阳性细胞百分率比较:治疗14d后中西医结合组显著高于西医治疗组[(48.87±1.98)%,(36.56±2.43)%,P<0.05];且显著高于中西医结合组入院时(33.89±1.45)%(P<0.05)。结论:中药复方清热颗粒制剂能够上调肾移植术后肺炎患者外周血淋巴细胞HLA-DR表达。     

辽西地区汉族成人的体型特征

目的:应用Heath-Carter法分析辽西地区汉族成人的体型特征,为体质人类学补充必要的资料。方法:于2002-09随机选择辽西地区20～82岁的汉族成人1002名(男490名,女512名)为测量对象。从20岁起,每5岁为一组,55岁以上为1个年龄组;每个年龄组按性别又分男、女两个小组,每小组测量人数不低于30名。由专人负责按Heath-Carter体型法进行指标测量和计算。10项测量指标分别是身高、体质量、上臂紧张围、小腿围、肱骨和股骨内外上髁间径、肱三头肌皮褶厚度、肩胛下皮褶厚度、髂前上棘皮褶厚度、腓肠肌皮褶厚度,测试数据按年龄、性别在微机中建立数据库。依次计算出各年龄组的内因子、中因子、外因子、体型图上的X,Y坐标值、身高体质量比、体型位置均数、两体型点间距离、体脂率和各类体型分布频数等。结果:1002名的各项指标均被测量,全部进入结果分析。①城市男女在内因子值(代表脂肪发育程度)方面占有明显的优势,中因子值(代表骨骼肌肉发育程度)方面和外因子值(代表身材相对瘦削程度)方面,城乡两组呈交替领先局面。提示汉族成人城市男女与农村男女相比,脂肪较发达,骨骼肌肉发育中等,身体线性度较差。②男性体型分布主要集中在偏中胚层的内胚层体型(53.5%),均衡内胚层体型(13.9%),偏外胚层的内胚层体型(9.1%),女性体型分布主要集中在偏中胚层的内胚层体型(62.8%),偏外胚层的内胚层体型(16.3%),均衡内胚层体型(13.7%)。体型频数分布提示汉族成年男女体型分布均较集中,以女性最为突出。③男女间体型相比,只有20～24岁和40～44岁年龄组男女间差异有显著性意义(P<0.05),其余各组差异无显著性意义。提示20～24岁为青春期的发育后期,男性得到充分的发育,而女性由于发育较早,发育已经停滞或缓慢。40～44岁女性更容易有脂肪沉积,而影响到其他有关体型的参数,出现男女差异。④辽西汉族城市成年人与农村成年人体型比较,内因子值城市成年男女均明显高于农村成年男女,中因子值和外因子值城乡较为接近,差异无显著性意义。结论:辽西地区城市成年男女骨骼、肌肉中等发达,体脂较多,身体线性度较差;农村成年男女,骨骼、肌肉较发达,体脂少于城市成人,身体线性度尚佳。     

Acanthopanax senticosus root inhibits mast cell-dependent anaphylaxis

BACKGROUND: Mast cells synthesize and secrete chemical mediators which play a central role in anaphylaxis. METHODS: The effect of Acanthopanax senticosus root (ASR) on mast cell-dependent anaphylaxis was investigated. RESULTS: ASR inhibited compound 48/80-induced systemic anaphylactic shock at the dose of 1.0 g/kg by 50%. When ASR was given as pre-treatment at concentrations ranging from 0.01 to 2.0 g/l, the histamine release from rat peritoneal mast cells induced by compound 48/80 was reduced in a dose-dependent manner. ASR (2.0 g/kg) also inhibited passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) IgE to 53.17+/-6.62%. Moreover, ASR inhibited tumor necrosis factor-alpha production in a concentration-dependent manner, and the treatment of 1 g/l blocked the production by 32.5+/-3.50% compared to saline value. CONCLUSIONS: ASR may possess effective anti-anaphylactic activity.     

Endoscopic salvage treatment of histoacryl after stent application on the anastomotic leak after gastrectomy: A case report

BACKGROUNDEndoscopic approach could effectively manage postoperative anastomotic leakage. Various endoscopic methods have been developed for the treatment of anastomotic leakage.CASE SUMMARYA 53-year-old woman developed anastomotic leak after laparoscopic proximal gastrectomy. Endoscopic clip closure failed due to strong wall tension; therefore, a fully covered self-expandable esophageal metal stent (fc-SEMS) was placed to cover the leak after it was filled with a mixture of fibrin glue and histoacryl. However, fluoroscopy with gastrograffin showed dye leaking out of the fc-SEMS. Using the previous fluoroscopic image for guidance, a catheter was inserted at the leakage site. The radiocontrast dye was injected and was seen spreading along the sinus tract. Thereafter, histoacryl was injected. Seven days after the last procedure, upper gastrointestinal contrast studies showed no leaks. The patient was subsequently discharged 9 d after histoacryl injection without any complications.CONCLUSIONTo seal an anastomosis leak after stent application, salvage technique using histoacryl injection at the leakage site with fluoroscopy guidance could be considered cautiously.     

Oral sodium phenylbutyrate therapy in homozygous beta thalassemia: a clinical trial

Butyrate analogues have been shown to increase fetal hemoglobin (HbF) production in vitro and in vivo. Sodium phenylbutyrate (SPB), an oral agent used to treat individuals with urea-cycle disorders, has been shown to increase HbF in nonanemic individuals and in individuals with sickle cell disease. We have treated eleven patients with homozygous beta thalassemia (three transfusion dependent) and one sickle-beta- thalassemia patient with 20 g/d (forty 500-mg tablets) of SPB for 41 to 460 days. All patients showed an increase in the percent of F reticulocytes associated with treatment, but only four patients responded by increasing their Hb levels by greater than 1 g/dL (mean increase, 2.1 g/dL; range, 1.2 to 2.8 g/dL). None of the transfusion- dependent thalassemia subjects responded. Increase in Hb was associated with an increase in red blood cell number (mean increase, 0.62 x 10(12)/L), and mean corpuscular volume (mean increase, 6 fL). Changes in percent HbF, absolute HbF levels, or alpha- to non-alpha-globin ratios as measured by levels of mRNA and globin protein in peripheral blood did not correlate with response to treatment. Response to treatment was not associated with the type of beta-globin mutation, but baseline erythropoietin levels of greater than 120 mU/mL was seen in all responders and only two of eight nonresponders to SPB. Compliance with treatment was greater than 90% as measured by pill counts. Side effects of the drug included weight gain and/or edema caused by increase salt load in 2/12, transient epigastric discomfort in 7/12, and abnormal body odor in 3/12 subjects. Two splenectomized patients who were not on prophylactic antibiotics developed sepsis while on treatment. We conclude that SPB increases Hb in some patients with thalassemia, but the precise mechanism of action is unknown.     

Guidance on home blood pressure monitoring: A statement of the HOPE Asia Network

Hypertension is an important modifiable cardiovascular risk factor and a leading cause of death throughout Asia. Effective prevention and control of hypertension in the region remain a significant challenge despite the availability of several regional and international guidelines. Out‐of‐office measurement of blood pressure (BP), including home BP monitoring (HBPM), is an important hypertension management tool. Home BP is better than office BP for predicting cardiovascular risk and HBPM should be considered for all patients with office BP ≥ 130/85 mm Hg. It is important that HBPM is undertaken using a validated device and patients are educated about how to perform HBPM correctly. During antihypertensive therapy, monitoring of home BP control and variability is essential, especially in the morning. This is because HBPM can facilitate the choice of individualized optimal therapy. The evidence and practice points in this document are based on the Hypertension Cardiovascular Outcome Prevention and Evidence (HOPE) Asia Network expert panel consensus recommendations for HBPM in Asia.     

Expert panel consensus recommendations for ambulatory blood pressure monitoring in Asia: The HOPE Asia Network

Hypertension is an important public health issue because of its association with a number of significant diseases and adverse outcomes. However, there are important ethnic differences in the pathogenesis and cardio‐/cerebrovascular consequences of hypertension. Given the large populations and rapidly aging demographic in Asian regions, optimal strategies to diagnose and manage hypertension are of high importance. Ambulatory blood pressure monitoring (ABPM) is an important out‐of‐office blood pressure (BP) measurement tool that should play a central role in hypertension detection and management. The use of ABPM is particularly important in Asia due to the specific features of hypertension in Asian patients, including a high prevalence of masked hypertension, disrupted BP variability with marked morning BP surge, and nocturnal hypertension. This HOPE Asia Network document summarizes region‐specific literature on the relationship between ABPM parameters and cardiovascular risk and target organ damage, providing a rationale for consensus‐based recommendations on the use of ABPM in Asia. The aim of these recommendations is to guide and improve clinical practice to facilitate optimal BP monitoring with the goal of optimizing patient management and expediting the efficient allocation of treatment and health care resources. This should contribute to the HOPE Asia Network mission of improving the management of hypertension and organ protection toward achieving “zero” cardiovascular events in Asia.     

Laboratory diagnosis of syphilis: A survey to examine the range of tests used in Canada

Laboratory diagnosis of syphilis has undergone major changes in the past decade with the introduction of immunoassays and recombinant Treponema pallidum antigens as screening tools for syphilis infection. To address this change in laboratory practice, a national syphilis laboratory working group was established with members from the Public Health Agency of Canada, provincial public health laboratories across the country as well as sexually transmitted infection researchers, clinicians and epidemiologists. This working group aims to examine how the use of newer immunoassays will affect syphilis diagnosis, surveillance and disease management. To provide a baseline for this work, an e-mail survey was conducted in the fall of 2009 to determine current laboratory practices for syphilis diagnosis in Canada. The most commonly used tests were rapid plasma reagin, enzyme immunoassay, T pallidum passive particle agglutination, venereal disease research laboratory, fluorescent treponemal antibody absorption, line immunoassay and polymerase chain reaction with 92%, 36%, 32%, 20%, 12%, 12% and 12% of the responding laboratories reporting using these tests, respectively. The ultimate goal of this working group will be to update laboratory guidelines for the diagnosis of syphilis, and to identify syphilis surveillance and research priorities in Canada.     

米帕明对局灶性脑缺血再灌注大鼠脑组织一氧化氮浓度和一氧化氮合酶活性的影响

目的:观察米帕明对局灶性脑缺血再灌注大鼠脑组织中含一氧化氮浓度和一氧化氮合酶活性的影响。方法:实验于2005-03/12在解放军总医院老年心血管病研究所生化药理实验室进行。①选用健康Wistar大鼠96只,随机分成假手术组、模型组、尼莫地平组和米帕明组4组,每组24只。②米帕明组腹腔注射米帕明10mg/kg,尼莫地平组腹腔注射尼莫地平2mg/kg,假手术组和模型组腹腔注射等容积生理盐水;60min后用线栓法建立大鼠局灶性脑缺血-再灌注损伤模型,假手术组尼龙线的头端不插入颈内动脉。③于缺血2h再灌注2,12和24h每组随机取6只大鼠断头,测定脑组织中一氧化氮浓度和一氧化氮合酶活性。每组剩余6只再灌注2h处死取脑,光镜下观察脑组织病理变化。结果:96只大鼠进入结果分析。①一氧化氮浓度:模型组、尼莫地平组和米帕明组再灌注2,12和24h均高于假手术组(P<0.05);尼莫地平组再灌注2,12和24h均低于模型组[(45.99±8.13),(40.63±3.13),(36.72±4.38)μmol/L;(65.54±6.01),(57.08±4.79),(48.13±5.12)μmol/L;P均<0.05];米帕明组再灌注2h和24h也低于同期模型组[(55.98±6.89),(39.42±4.28)μmol/L;P均<0.05]。②一氧化氮合酶活性:模型组、尼莫地平组和米帕明组再灌注2,12和24h均高于假手术组(P<0.05);尼莫地平组和米帕明组各个时间点均低于模型组(P<0.05)。③脑组织病理变化:尼莫地平组和米帕明组神经元损伤较模型组轻。结论:米帕明可降低局灶性脑缺血再灌注大鼠脑组织中一氧化氮浓度和一氧化氮合酶活性,从而对大鼠脑缺血再灌注有保护作用,其效果与尼莫地平相似。