Colite lymphocytaire : apport du pathologiste et interaction entre clinicien et pathologiste

Lymphocytic colitis (LC), a rare entity in microscopic colitis, is an inflammatory disease of the colonic mucosa. The pathologist plays a key role in the positive diagnosis of LC by eliminating a number of differential diagnoses. However, this diagnosis depends on the interaction between the clinician and the pathologist and comparison between histological and clinical findings, which enable correct interpretation. The majority of recent work enhances our knowledge of the histopathogenic, causal and therapeutic factors. However, the debate about the distinction between LC and collagen colitis is still going on, in which the pathologist plays a key role. The diagnosis of microscopic colitis is purely based on the findings of histological examination of systematic colonic biopsies, with a correlation between the clinical manifestations of the patient with chronic diarrhoea and normal endoscopy and the morphology of biopsies of LC lesions. The purpose of our study is to clarify the role and contribution of the pathologist in positive and differential diagnosis of LC and to discuss the interaction between clinicians and pathologists.     

高场磁共振成像仪安装的经验与教训

本文介绍我院在安装多台磁共振成像仪的过程中所出现的问题,以及所得的经验与教训,对提高预安装的工作质量有一定的帮助。     

Evolutionary evidence of the effect of rare variants on disease etiology

Gorlov IP, Gorlova OY, Frazier ML, Spitz MR, Amos CI. Evolutionary evidence of the effect of rare variants on disease etiology. The common disease/common variant hypothesis has been popular for describing the genetic architecture of common human diseases for several years. According to the originally stated hypothesis, one or a few common genetic variants with a large effect size control the risk of common diseases. A growing body of evidence, however, suggests that rare single‐nucleotide polymorphisms (SNPs), i.e. those with a minor allele frequency of less than 5%, are also an important component of the genetic architecture of common human diseases. In this study, we analyzed the relevance of rare SNPs to the risk of common diseases from an evolutionary perspective and found that rare SNPs are more likely than common SNPs to be functional and tend to have a stronger effect size than do common SNPs. This observation, and the fact that most of the SNPs in the human genome are rare, suggests that rare SNPs are a crucial element of the genetic architecture of common human diseases. We propose that the next generation of genomic studies should focus on analyzing rare SNPs. Further, targeting patients with a family history of the disease, an extreme phenotype, or early disease onset may facilitate the detection of risk‐associated rare SNPs.     

Cellular infiltration and cytokine mRNA expression in perennial allergic rhinitis

BACKGROUND: Allergen challenge in allergic rhinitis patients leads to local eosinophilia and Th2-type cytokine expression. Natural exposure to grass pollen is additionally characterized by epithelial mast-cell infiltration. We hypothesized that perennial allergic rhinitis is also associated with T-cell and eosinophil infiltration of the nasal mucosa, local Th2-type cytokine expression, and increased numbers of nasal epithelial mast cells. METHODS: Nasal biopsies from perennial allergic rhinitis patients and controls were analysed by immunocytochemistry for different cell populations and in situ hybridization for cytokine mRNA-expressing cells. RESULTS: Perennial allergic rhinitis was associated with increased numbers of submucosal CD3+ T cells (P=0.05), EG2+ activated eosinophils (P=0.01), and CD68+ macrophages (P=0.01) compared to controls. Epithelial, but not submucosal, tryptase-positive mast cells were also elevated in rhinitics compared to controls (P=0.01). The numbers of cells expressing interleukin (IL)-5 were higher (P=0.01) and the numbers of cells expressing IL-2 were lower (P=0.04) in rhinitic patients than controls. There were no significant differences for either IL-4 or interferon-gamma between the groups. CONCLUSIONS: Perennial allergic rhinitis is characterized by mast-cell migration into the epithelium; submucosal infiltration by T cells, eosinophils, and macrophages; and an imbalance in local T-cell cytokine production in favour of enhanced IL-5 and reduced IL-2 expression.     

冠状动脉运动规律的磁共振电影成像研究

目的利用磁共振电影成像研究冠状动脉的运动规律.方法选取不同心率的志愿者35例,使用电影成像序列显示冠状动脉断面的运动轨迹,以5% R-R间期为标准化时间单位(NTU),分析冠状动脉运动轨迹和速度的特征.结果冠状动脉各分支的运动轨迹存在个体差异.当心率小于75 bpm时,RCA和LCX在ECG触发延迟75% R-R的舒张中期和40% R-R的收缩末期运动速度小于3 mm/NTU,LAD在整个心动周期运动速度基本都小于3 mm/NTU.结论心率小于75 bpm时,建议选择舒张中期进行冠状动脉的断层采样或者重建.     

正常舟月韧带厚度超声与MRI研究

目的提供舟月韧带厚度(SLLT)超声测量正常值,评价超声测量舟月韧带厚度的准确性.方法用超声高频探头探查200只正常手腕,与MRI测量其中的30人60只手腕比较.记录超声和MRI图像上SLLT测值.结果舟月韧带在背侧部正中位声像图最清晰.男、女性舟月韧带背侧部厚度(SLLTd)分别为(2.18±0.35) mm和(1.99±0.23) mm.超声与MRI在测量SLLT相关性比较呈直线相关(P<0.01).结论超声能够清晰显示并准确测量舟月韧带的厚度.