从西藏微小牛蜱检出类查菲埃立克体和边缘无形体16S rDNA

目的　鉴定微小牛蜱 (Boophilusmicroplus)所携带的埃立克体病原体。方法　依据蜱传埃立克体 16SrDNA序列设计引物 ,建立埃立克体属特异性套式PCR检测微小牛蜱DNA样本 (每份DNA由 2个蜱提取 ) ;克隆DNA样本中的埃立克体 16SrDNA的 5′末端片段并测定其序列。结果　西藏某地的 4 3份蜱DNA样本中有 16份 (37% )经套式PCR扩得阳性片段 ,而四川某地的 2 7份蜱DNA样本扩增结果均为阴性。测定 16SrDNA的 5′末端片段 (～ 4 5 0bp)的序列 ,发现两种序列 ,一种与边缘无形体 16SrDNA完全一致 ,另一种与查菲埃立克体 16SrDNA最相关 ,但它们之间有 7个碱基 (～ 1 6 % )的不同。结论　西藏某地的微小牛蜱中携带有类查菲埃立克体和边缘无形体 ,该类查菲埃立克体可能是一个埃立克体新种     

蜱中人粒细胞埃立克体DNA的PCR检测及序列分析

目的了解吉林地区蜱种感染人粒细胞埃立克体的情况。方法采用16S rRNA基因特异引物进行半套式PCR,检测吉林省部分林区蜱中人粒细胞埃立克体DNA,并对扩增产物进行克隆和测序,与已知序列进行同源性比较。结果从采集于吉林地区的全沟硬蜱中检出人粒细胞埃立克体的特异性DNA片段,阳性率为1.98%。扩增产物经克隆、测序发现吉林地区人粒细胞埃立克体扩增片段与美国人粒细胞埃立克体分离株(GenBank注册号为U02521)16SrRNA基因序列相对应片段相差2个核苷酸,同源性为99.7%。结论吉林地区的全沟硬蜱携带人粒细胞埃立克体,提示吉林地区可能存在人粒细胞埃立克体病的自然疫源地。     

福建厦门微小牛蜱中埃立克体的检测与鉴定

目的 检测福建厦门微小牛蜱携带的埃立克体，进行分类鉴定。方法 采用套式PCR方法检测埃立克体，然后对阳性标本中的埃立克体进行16SrRNA全基因序列测定并分析。结果 共检测吸血微小牛蜱标本299份，27份阳性，阳性率为9．0％。选择其中的1份阳性样本扩增16SrRNA的全基因序列，全长1458bp，序列对比显示与泰缅边境和越南的埃立克体同源性为99．9％，相差2个碱基；与西藏埃立克体同源性为99．7％，相差4个碱基；与非洲埃立克体同源性为99．6％，相差7个碱基；与中国南方的查菲埃立克体同源性为98．9％，相差17个碱基。结论 从福建厦门微小牛蜱中检测到埃立克体，可能是一个埃立克体新的亚种。     

湖北省随州市羊携带嗜吞噬细胞无形体的调查

目的调查湖北省随州市羊携带嗜吞噬细胞无形体的状况。方法运用聚合酶链反应方法对湖北随州市采集的羊血标本进行嗜吞噬细胞无形体16SrRNA基因片段进行扩增和序列分析,将扩增序列与GenBank相应基因序列进行同源性比较和进化分析。结果共检测羊血标本29份,阳性标本25份,嗜吞噬细胞无形体阳性感染率为86．2％;所检出的嗜吞噬细胞无形体16SrRNA基因（1442bp）与GenBank中收录的部分嗜吞噬细胞无形体16srRNA基因序列的同源性高达97．1％～99．8％,进化分析显示与嗜吞噬细胞无形体同在一个分支上。结论湖北随州地区山羊存在嗜吞噬细胞无形体的感染。     

广州市郊鼠中检出埃立克体样微生物

目的　了解曾经两次暴发犬埃立克体病流行的广州市郊某养犬基地野生啮齿动物感染埃立克体情况。方法　用 16SrRNA基因埃立克体属特异引物对抓捕的动物全血及脾脏样本进行PCR检测 ,阳性样本克隆测序 ,所得序列与Gen Bank中注册的核苷酸序列进行比较。结果　在所抓捕的 2 6只野生啮齿动物中 ,3份褐家鼠全血样本和一份脾样本检出埃立克体特异阳性带。序列测定结果显示 ,这 3只鼠所携带的埃立克体样微生物基因完全一致。该基因与核酸数据库中的埃立克体Schotti株有最大同源性 (99 0 4 % )。结论　此次发现的埃立克体与该基地流行的犬埃立克体Gzh982株和扁平埃立克体Gzh981株有很大差异。该菌在流行病学上的意义有待进一步研究。     

通辽市家畜感染无形体属病原体的调查

目的 调查内蒙古通辽地区绵羊和牛的无形体感染情况。方法 采用PCR方法检测内蒙古通辽市扎鲁特旗及科左中旗散放76只绵羊和20头牛的血样本,扩增嗜吞噬细胞无形体(Anaplasma phagocytophilum)、中央无形体(A. centrale)和牛无形体(A. bovis)的16S rRNA基因和羊无形体(A. capra)的gltA基因。结果 76只绵羊血样本中37份扩增到嗜吞噬细胞无形体目的基因,阳性率为 48.7%;76只绵羊血样本中16份扩增到中央无形体目的基因,阳性率为21.1%。所有绵羊的血样本均未扩增到羊无形体和牛无形体的目的基因,20头牛的血样本均未扩增到4种无形体的目的基因。结论 通辽地区羊存在嗜吞噬细胞无形体和中央无形体感染,提示该地区存在无形体病的自然疫源地和可能存在人无形体病。     

云南临沧地区蜱种分子生物学鉴定及埃立克体基因序列分析

目的 了解云南临沧地区蜱虫种类及其自然感染埃立克体的情况。方法 采集耕牛体表寄生的蜱虫,经形态学鉴定和分组后,从蜱虫中提取DNA,应用PCR扩增蜱虫COI基因以及埃立克体16S rRNA和groEL基因,并测序分析。结果 共采集到蜱虫42只,其中微小牛蜱38只占90.48%、血蜱4只占9.52%。将每种蜱的2只为1组,在21组样本中,检出COI片断21份(检出率100%);在相同的4组样本中均检出埃立克体16S rRNA片断和groEL片断4份(检出率19.05%)。基因序列分析,检出的COI片断序列中有2份与澳大利亚pava血蜱(JX573136)的同源性最高(89.3%),其余19份序列与马来西亚微小牛蜱B3的同源性最高(99.5%);检出的4份16S rRNA片断序列完全一致,与美国查菲埃立克体Arkansas和埃文埃立克体Aa2FT349及中国北京查菲埃立克体BY-YQ-HME-O18株的同源性均为100%;检出的4份groEL片断序列也完全一致,与日本埃立克体Yonaguni206 株的同源性最高均为93.9%。结论 经分子检测证实云南临沧地区耕牛体表微小牛蜱中存在一种类似日本Yonaguni206株的埃立克体感染,耕牛体表还可能寄生一种新的血蜱。     

云南省泸西县啮齿动物携带立克次体调查

目的 调查云南省泸西县啮齿动物携带恙虫病东方体、无形体和埃立克体的状况,了解该类病原体在当地自然界中的保存状况和基因特征。方法 用鼠笼和鼠夹在云南省泸西县捕鼠,将捕获的动物种类鉴定后解剖取脾脏,活鼠取血。采用巢式PCR扩增脾脏的恙虫病东方体groEL基因,无形体和埃立克体的16S rRNA基因特异片段;测定PCR扩增阳性产物的DNA序列,对获得序列进行序列比对和系统进化分析。IFA法检测鼠血清中恙虫病东方体IgG抗体。结果 在泸西县共捕获啮齿动物10种225只。其中黄胸鼠36.89%(83/225)、大绒鼠35.11%(79/225)和中华姬鼠13.78%(31/225)为优势鼠种。获得鼠血清85份。鼠脾脏中检测到5株东方体groEL基因阳性标本,带毒鼠种为黄胸鼠2.41%(2/83)和大绒鼠3.80%(3/79)。同源性比较显示,这5株东方体的相似性在99.02%~100%之间,他们分别与GenBank中已知立克次体序列的相似性在98.75%~100%。系统发生树显示,5株OT与来自日本、泰国和中国安徽的菌株位于同一分支。3份16S rRNA阳性标本,其中1份埃立克体阳性,来源于大绒鼠;1份沃尔巴克氏体和1份巴尔通体阳性均来源于黄胸鼠。无形体均为阴性。埃立克体株序列比对显示与来自美国、中国和巴西的埃立克体基因同源性为98.0%~100%,并与分离自美国野外工作者皮肤的伊文氏埃立克体在同一分支。鼠血清恙虫病IgG抗体阳性7份,阳性率8.24%(7/85)。结论 该地区存在以黄胸鼠和大绒鼠为主要宿主的恙虫病自然疫源地。埃立克体、巴尔通体和沃尔巴克氏体在啮齿动物中也存在感染,需注意防控。     

福建省鼠类携带新埃立克体调查及16S rRNA和groEL基因特征研究

目的调查福建省鼠类携带新埃立克体情况,了解福建新埃立克体的16S rRNA和groEL基因特征。方法在福建省5个市15个县(市、区)采用笼日法捕鼠,心脏采血,PCR扩增新埃立克体的16S rRNA基因和groEL基因,纯化、测序后进行序列比对分析。结果福建省鼠中新埃立克体阳性率为6.67%,福州、南平、三明和宁德4个市的8个县检出新埃立克体,以三明市阳性率较高,为12.21%;其次为南平、宁德市和福州市分别为6.61%、5.56%和3.51%。黄胸鼠、褐家鼠、板齿鼠和黄毛鼠均有新埃立克体检出,其中野鼠阳性率为9.40%,以板齿鼠阳性率较高,为23.53%;家鼠阳性率为4.28%,以黄胸鼠阳性率较高,为6.94%。家鼠和野鼠阳性率差异有统计学意义(P0.05)。影响鼠类感染新埃立克体的因素为鼠龄和生境。序列分析显示福建省鼠感染新埃立克体的16S rRNA和groEL基因序列高度一致。结论福建省鼠类新埃立克体感染普遍,且基因序列高度同源。属新埃立克体的自然疫源地,可为福建省新埃立克体病的防治提供基础资料和参考。     

山东省沂源县无形体病实验室调查分析

目的通过山东省沂源县人粒细胞无形体及其他立克次体病疫源地小样本试点调查,为全面深入开展立克次体病调查提供数据支持.方法对2004、2005、2006年该地区调查收集的26例可疑患者标本进行血清IgG抗体及PCR回顾性检测分析.2007年7月进一步现场流行病学调查,采集当地48名正常人、10只山羊及8只家狗的血标本以及170只蜱标本进行血清学及分子生物学检测分析.结果 26例发热患者中,8例明确诊断为人粒细胞无形体感染,6例为可疑病例.当地正常人群人粒细胞无形体IgG抗体阳性率为26.7%,人单核细胞埃立克体IgG抗体阳性率为1.8%.检测的10份家养黑山羊血清标本9份阳性.8份家狗标本中,人粒细胞无形体抗体7份阳性,而人单核细胞埃立克体血清抗体全部阳性.来自发热患者、山羊及媒介蜱标本PCR扩增16S rRNA及部分序列分析结果显示高度同源性(100%).结论沂源县农业人群普遍存在人粒细胞无形体、人单核细胞埃立克体及其他立克次体隐性感染状况.当地主要优势蜱种为长角血蜱及嗜群血蜱,两者可能是人粒细胞无形体的重要传播媒介.黑山羊可能是人粒细胞无形体的重要动物宿主,而家狗可能是人粒细胞无形体及人单核细胞埃立克体两者兼顾的重要动物宿主.     

胰岛素瘤的解剖分布特点分析

目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤，因其临床表现多样，导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用，拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点，以期有助于提高影像学的诊断准确率和降低漏诊率，尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料，检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例，通过查阅病例的方法，提取出胰岛素瘤的大小和解剖分布等数据，进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例，其中，男45例、女71例，年龄13～76岁，平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布：头颈部46例(39.7%)，单发45例、多发1例；体尾部68例(58.6%)，单发65例、多发3例；全胰腺多发2例(1.7%)。病变大小特点：最大径0.4～3.4 cm，平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例，≤3 cm 15例，>3 cm 3例。年龄与肿瘤的大小相关，≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm，P<0.05。头颈部的肿瘤大于体尾部的肿瘤，头颈部肿瘤平均大小(1.66±0.63)cm，体尾部(1.42±0.52)cm，P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发；绝大多数单发，但可以全胰腺多发；多数小于1.5 cm，肿瘤的大小与患者年龄和肿瘤的解剖分布相关。     

Pathogenesis of carcinoma of the papilla of Vater

Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.     

Demonstration of the mechanism of action of biguanides

Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.     

Lack of correlation of degree of villous atrophy with severity of clinical presentation of coeliac disease

BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.     

血吸虫童虫生长发育及其机制的研究进展

血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。     

氯硝柳胺悬浮剂的毒性评价

目的评价氯硝柳胺悬浮剂的毒性，为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg，经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3，该药经口、经皮肤、经呼吸道毒性均属微毒类药物；兔眼用药后，观察期内无不良反应，对眼无刺激性；皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比，氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物，对鱼的毒性低于其乙醇胺盐可湿性粉剂，适合于现场应用。     

124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。     

Assessment of quality of life of parents of children with juvenile chronic arthritis

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002     

Numerical Simulation of the Effect of Rate of Change of Glucose on Measurement Error of Continuous Glucose Monitors

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl⁻¹•min⁻¹ (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl⁻¹•min⁻¹ (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.     

Study of constancy of hydrogen-consuming flora of human colon

The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H₂-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.