El Tor型霍乱弧菌L型的某些生物学性状

本研究主要对El Tor型霍乱弧菌(Vibrio cholerae biotvpe eltor,EVC)L型的某些生物学特性如生化反应、抗生素敏感性及超微结构等进行了探讨.研究发现EVC不稳定L型的生化性状与EVC流行株的非常相似,而稳定L型则变化很大.抗生素敏感性试验显示EVC稳定L型对某些作用于细胞壁的抗生素的敏感性减弱,而对大多数作用于蛋白质合成的抗生素的敏感性增强.与流行株相比,EVC稳定L型和不稳定L型的超微结构的改变很明显.此外,本文还讨论了产生这些改变的可能机制.     

我国5岁以下儿童小肠结肠炎耶尔森菌感染临床特征及病原学分析

目的 了解我国5岁以下儿童小肠结肠炎耶尔森菌腹泻病例临床与病原学特征,分析其可能的感染来源,为小肠结肠炎耶尔森菌病的防控与诊断提供科学依据。 方法 收集2010—2020年间来自全国10个省市自治区哨点医院儿童腹泻标本、调查及回访问卷;对标本进行小肠结肠炎耶尔森菌的分离鉴定;菌株进行生物分型、血清型鉴定;毒力基因检测以及脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)分型。 结果 2010—2020年共监测11 377例,分离到致病性小肠结肠炎耶尔森菌63株,包括61株O:3血清型、2株O:9血清型菌株,5岁以下腹泻儿童感染率0.55%(63/11 377)。不同性别儿童对致病性小肠结肠炎耶尔森菌的感染率差异无统计学意义,1～5岁感染率高于≤1岁病例(χ²=44.836,P＜0.05),感染患儿中1～5岁发热比例高于≤1岁(χ²=11.508 ,P<0.05),随访病例未发现后遗症。我国儿童感染O:3血清型致病性小肠结肠炎耶尔森菌的PFGE带型存在多样性,优势带型为K6GN11C30021、K6GN11C30012。 结论 我国5岁以下儿童感染致病性小肠结肠炎耶尔森菌的生物血清型以3/O:3为主,偶有4/O:3与2/O:9。根据患儿感染特点与高发季节推测食源为主要感染来源,需进一步调查研究。     

锥形束CT测量牙龈厚度准确性的初步研究

目的评价锥形束CT(CBCT)法测量牙龈厚度的可信度及准确性。方法选择20例牙龈健康者的120颗上颌前牙,采用CBCT法和牙龈穿刺法测量唇侧中央龈缘下2mm处牙龈厚度,比较两组差异并用Kappa系数评价两种方法的一致性;应用Kappa系数评价不同检查者用CBCT法测量牙龈厚度的一致性,以及组内相关系数ICC评价同一检查者重复测量数据的可信度。结果CBCT法测量牙龈厚度为(1.23±0.27)mm,牙龈穿刺法测量结果为(1.24±0.26)mm,差异无统计学意义(P>0.05),两组之间一致率为83.33%(Kappa=0.547)。不同的检查者CBCT法测量牙龈厚度的一致性检验Kappa系数为0.814,可信度良好(ICC=0.795),同一检查者CBCT法重复测量数据之间一致性检验Kappa系数为0.864,可信度良好(ICC=0.893);CBCT法对厚牙龈生物型具有高的灵敏度(92.05%)和低的特异度(59.38%)。结论CBCT测量牙龈厚度的结果与牙龈穿刺法的结果较一致,具有良好的可信度。     

Periodontally accelerated osteogenic orthodontics with platelet-rich fibrin in an adult patient with periodontal disease: A case report and review of literature

BACKGROUNDIn the clinical scenario, adult patients with periodontal diseases and dental malformation, characterized by dental crowding in lower anterior teeth with the thin biotype, often require orthodontic treatment. This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics (PAOO) combined with autologous platelet-rich fibrin (PRF) in an adult patient with class I malocclusion along with dental crowding, a thin periodontal biotype, and buccal plate deficiency.CASE SUMMARYA 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic. The patient underwent periodontal risk assessment prior to orthodontic treatment. She was diagnosed with a high risk of gingival recession due to dental crowding, root prominence, loss of buccal plates, and a thin gingival tissue biotype. The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding. Clinically, PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling. Radiographic outcomes also showed statistically significant improvements (P < 0.01) in the mandibular buccal alveolar bone. CONCLUSIONThis case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.     

On the relationship between crown form and clinical features of the gingiva in adolescents

Abstract The purpose of the present study was to examine the relationship between the form of the crowns in the maxillary front tooth segment and (1) a group of morphological characteristics and (2) the thickness of the gingiva. 108 subjects devoid of symptoms of destructive periodontal disease were examined regarding, e.g., probing depth, thickness of the free gingiva, width of the keratinized gingiva and the contour of the marginal gingiva. From clinical photographs of the maxillary front tooth region, the width (at the apical third – CW) and the length (CL) of the crowns of the 6 front teeth were determined. A CW/ CL-ratio was calculated for each tooth and averaged for each tooth region. The individual mean CW/CL-ratio values for the central incisors were ranked. After correction for incisal attrition, the 10 subjects ranked highest and the 10 ranked lowest were selected as having either a long-narrow (group N) or a short-wide (group W) form of the crown of the tooth. The data for each of the examined parameters were averaged for each tooth region in each subject and mean values for subjects in groups W and N were compared using the Student t-test. Stepwise multiple regression analysis, including data from the whole sample, was performed for each tooth region with the thickness of the free gingiva as the dependent variable. The results from the analyses demonstrated that individuals with a long-narrow form of the central incisors displayed, compared to individuals with a short-wide crown, form (i) a narrow zone of keratinized gingiva, (ii) shallow probing depth, and (hi) a pronounced “scalloped” contour of the gingival margin. There was no significant difference between groups N and W with respect to the thickness of the free gingiva. The CW/CL-ratio data revealed that a certain form of the crowns in the central incisors was accompanied by a similar form in the lateral incisor and canine tooth region. The regression analyses demonstrated that the thickness of the free gingiva in central incisors was significantly related to (i) the width of the keratinized gingiva, (ii) the buccolingual width of the crown and (iii) the presence of an interproximal gingival groove. In lateral incisors, the thickness of the free gingiva was associated with the probing depth at the buccal surface. No single variable was significantly related to the thickness of the gingiva in canines.     

中国汉族成人后牙区硬腭黏膜厚度测量及各组织学层次分布规律研究

目的 本文测量中国汉族人群中后牙区硬腭黏膜的厚度,分析其变化规律及相关因素,观察硬腭黏膜固有层结缔组织各组织学层次的厚度、特点及分布规律。方法 36例患者根据牙龈生物型（gingiva biotype）分为三组,使用骨探测法（bone sounding）测量由尖牙至第二磨牙腭侧共45个位点硬腭黏膜的厚度,采集牙周软组织增量手术中移植软组织修剪下来的剩余组织,筛选具有硬腭黏膜全层的样本,采用免疫组化技术,镜下观察结缔组织的组织学特点及分布规律。结果 硬腭黏膜平均厚度(3.52±1.02）mm、尖牙区为(3.26±0.81）mm、第一前磨牙区为(3.57±1.05）mm、第二前磨牙区为(3.72±1.04）mm、第一磨牙区为(3.33±0.96）mm、第二磨牙区为(3.73±1.11）mm;硬腭黏膜的厚度与性别、年龄无显著相关性,与牙龈生物型之间存在统计学差异;HE染色显示硬腭黏膜结缔组织层具有致密的胶原纤维,由第二前磨牙区域开始出现明显的黏膜下层,在第一磨牙区域多见疏松结缔组织,内含大量脂肪组织、血管、腺体等。结论 在中国汉族人群中硬腭黏膜厚度由尖牙向后逐渐增厚,在第一磨牙区变薄,向第二磨牙区再次变厚;在尖牙、第一前磨牙和第二磨牙区可见由龈缘向腭中缝处黏膜厚度逐渐变厚;硬腭黏膜固有层含有致密的结缔组织,由第二前磨牙区开始出现黏膜下层,含大量脂肪组织、血管、腺体等。     

河北省布鲁菌流行菌株生物学特征分析

目的 了解河北省布鲁菌分离株的生物学特征.方法 应用传统分型鉴定方法和分子生物学方法确定布鲁菌属与种型鉴定.结果 8株分离菌株经传统分型方法鉴定均为羊种菌,羊1型1株,羊3型6株,粗糙型羊种菌1株;进一步采用布鲁菌属特异性BCSP31-PCR均扩增出223 bp的特异性条带;经种/型特异性AMOS-PCR均扩增出731bp的特异性条带,鉴定为羊种布鲁菌.结论 河北省近两年人感染布鲁氏菌的流行菌株为羊种菌3型,AMOS-PCR方法可以作为该省布鲁菌分离株鉴定的辅助手段.