Beyond genetics. Influence of dietary factors and gut microbiota on type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease ultimately leading to destruction of insulin secreting β-cells in the pancreas. Genetic susceptibility plays an important role in T1D etiology, but even mono-zygotic twins only have a concordance rate of around 50%, underlining that other factors than purely genetic are involved in disease development. Here we review the influence of dietary and environmental factors on T1D development in humans as well as animal models. Even though data are still inconclusive, there are strong indications that gut microbiota dysbiosis plays an important role in T1D development and evidence from animal models suggests that gut microbiota manipulation might prove valuable in future prevention of T1D in genetically susceptible individuals.     

2008～2009年青岛地区手足口病病原学的调查分析

本研究对2008～2009年青岛地区手足口病的病原学进行调查研究。首先对HFMD病例的咽拭子标本直接进行病毒核酸的提取,然后采用多重荧光逆转录-聚合酶链反应(RT-PCR)方法对总肠道病毒(Enterovirus,EV)、肠道病毒71型(Enterovirus Type 71,EV71)和柯萨奇病毒A组16型(Coxsackievirus Group A 16,CVA16)进行检测,对EV阳性而EV71和CVA16均阴性的标本采用半巢式反转录PCR进行肠道病毒VP1基因部分序列的扩增和序列分析以鉴定其血清型别。结果提示2008～2009年青岛地区手足口病的主要病原为EV71和CVA16,无论轻症和重症病例,EV71的比例都大于CVA16。2008年共获得5个(8株)其它血清型,分别是柯萨奇病毒(Cox-sackievirus,CV)的A5、A6、A10、A12及埃可病毒9(Echovirus 9,E9),血清型分布比较分散、均匀。2009年共获得3个其它血清型(13株),分别是CVA9、CVA12及CVB2,CVA12所占比例较大(11/13),分布比较集中。CVA12成为2009年青岛地区HFMD病原中除EV71和CVA16外,新的较为流行的病原。     

2009年全国其他感染性腹泻报告病例分析

目的了解我国2009年其他感染性腹泻的流行特点和病原学信息,提出改善建议,为更好的控制其他感染性腹泻病的流行提供数据支持。方法收集中国疾病控制信息系统"疾病监测信息报告管理系统"中2009年其他感染性腹泻的病例报告,对其流行病学及病原学信息进行描述性统计分析。结果 2009年全国共报告655 965例其他感染性腹泻病例,其中≤5岁儿童分别占报告总病例的50.38%和死亡病例的70.0%。实验室确诊病例占报告病例数的5.04%,其中病毒性感染占92.79%,细菌性感染占6.92%。结论≤5岁的散居儿童应为其他感染性腹泻的重点监测人群。其他感染性腹泻报告病例中约有95%为临床诊断病例。我国其他感染性腹泻的病原学诊断率及病原学诊断结果的报告率亟待提高。     

Detection of mosaicism in lymphocytes of parents of free trisomy 21 offspring

Down syndrome (DS) resulting from free trisomy 21 (FT21) has been largely associated with advanced maternal age. However, approximately 60% of FT21 cases are born to young couples. Thus, the etiological factors responsible for these FT21 children must differ from those proposed for maternal age-related FT21. These factors have not been defined. In this study, we analyzed the chromosomes of peripheral blood lymphocytes from three groups of couples aged ≤35 years, to identify chromosomal trisomies: Group I included 5 couples with normal offspring; Group II included 22 couples with one FT21 child; and Group III consisted of 3 couples with recurrent FT21. A total of 13,809 metaphases were analyzed with G-banding and 60,205 metaphases were analyzed with FISH using a 13/21 centromeric probe. Aneuploidy was significantly more frequent in Groups II and III. The frequencies of hyperdiploid cells were 0.19, 0.49 and 0.96% in Groups I–III, respectively. FISH analysis showed that trisomy 21 cell percentages were 0.08, 0.21 and 0.76 for Groups I–III, respectively, and were very similar to those obtained with G-banding. Trisomy 21 mosaicism was found in 2/22 couples with one FT21 offspring, and in 2/3 couples with recurrent FT21. Our data suggest that mosaicism is an important cause of FT21 offspring in young couples, and that aneuploidy is more frequent among couples with FT21 offspring. This may be related with age and other undetermined intrinsic and extrinsic factors.     

The aetiology of myocardial injury after non-cardiac surgery

Recognition of myocardial injury after non-cardiac surgery is difficult, since strong analgesics (e.g. opioids) can mask anginal symptoms, and ECG abnormalities are subtle or transient. Thorough knowledge of the pathophysiological mechanisms is therefore essential. These mechanisms can be subdivided into four groups: type I myocardial infraction (MI), type II MI, non-ischaemic cardiac pathology, and non-cardiac pathology. The incidence of type I MI in patients with a clinical suspicion of perioperative acute coronary syndrome (ACS) is 45–57 %. This percentage is higher in patients with a high likelihood of MI such as patients with ST-elevation ACS. Of note, the generalisability of this statement is limited due to significant study limitations. Non-ischaemic cardiac pathology and non-cardiac pathology should not be overlooked as a cause of perioperative myocardial injury (PMI). Especially pulmonary embolism and dysrhythmias are a common phenomenon, and may convey important prognostic value. Implementation of routine postoperative troponin assessment and accessible use of minimally invasive imaging should be considered to provide adequate individualised therapy. Also, addition of preoperative imaging may improve the stratification of high-risk patients who may benefit from preoperative or perioperative interventions.     

Antibody fingerprints in lyme disease deciphered with high density peptide arrays

Lyme disease is the most common tick‐borne infectious disease in Europe and North America. Previous studies discovered the immunogenic role of a surface‐exposed lipoprotein (VlsE) of Borreliella burgdorferi. We employed high density peptide arrays to investigate the antibody response to the VlsE protein in VlsE‐positive patients by mapping the protein as overlapping peptides and subsequent in‐depth epitope substitution analyses. These investigations led to the identification of antibody fingerprints represented by a number of key residues that are indispensable for the binding of the respective antibody. This approach allows us to compare the antibody specificities of different patients to the resolution of single amino acids. Our study revealed that the sera of VlsE‐positive patients recognize different epitopes on the protein. Remarkably, in those cases where the same epitope is targeted, the antibody fingerprint is almost identical. Furthermore, we could correlate two fingerprints with human autoantigens and an Epstein‐Barr virus epitope; yet, the link to autoimmune disorders seems unlikely and must be investigated in further studies. The other three fingerprints are much more specific for B. burgdorferi. Since antibody fingerprints of longer sequences have proven to be highly disease specific, our findings suggest that the fingerprints could function as diagnostic markers that can reduce false positive test results.     

体外牙周微生态模型构建方法及应用研究进展

牙周炎的病因学研究经历了从非特异性菌斑学说、特异性菌斑学说到生态菌斑学说的转变,但其具体的发病机制仍有待进一步研究.近年来,有学者提出了多微生物协同和生态失调模型,病原体组作为疾病病因学中的新概念也逐渐引起重视,这些都提示牙周感染中牙菌斑生物膜与宿主之间存在复杂的相互作用.因此,构建牙周微生态模型对牙周炎病因及防治的研...     

Is early osteoarthritis associated with differences in joint congruence?

Previous studies suggest that osteoarthritis (OA) is related to abnormal or excessive articular contact stress. The peak pressure resulting from an applied load is determined by many factors, among which is shape and relative position and orientation of the articulating surfaces or, referring to a more common nomenclature, joint congruence. It has been hypothesized that anatomical differences may be among the causes of OA. Individuals with less congruent joints would likely develop higher peak pressure and thus would be more exposed to the risk of OA onset. The aim of this work was to determine if the congruence of the first carpometacarpal (CMC) joint differs with the early onset of OA or with sex, as the female population has a higher incidence of OA. 59 without and 38 with early OA were CT-scanned with their dominant or arthritic hand in a neutral configuration. The proposed measure of joint congruence is both shape and size dependent. The correlation of joint congruence with pathology and sex was analyzed both before and after normalization for joint size. We found a significant correlation between joint congruence and sex due to the sex-related differences in size. The observed correlation disappeared after normalization. Although joint congruence increased with size, it did not correlate significantly with the onset of early OA. Differences in joint congruence in this population may not be a primary cause of OA onset or predisposition, at least for the CMC joint.     

A multi-etiology model of systemic degeneration in schizophrenia

We discuss the possibility of multiple underlying etiologies of the condition currently labeled as schizophrenia. We support this hypothesis with a theoretical model of the prefrontal-limbic system.We show how the dynamical behavior of this model depends on an entire set of physiological parameters, representing synaptic strengths, vulnerability to stress-induced cortisol, dopamine regulation and rates of autoantibody production. Malfunction of such different parameters produces similar outward dysregulation of the system, which may readily lead to diagnostic difficulties for a clinician.Techniques that provide a spectrum/profile of neural and steroid functions may be helpful in clarifying these diagnostic dilemmas.