COBALAMIN DEFICIENCY and SMALL BOWEL BACTERIAL OVERGROWTH: A COMMON ASSOCIATION

Background  Bacterial overgrowth may cause cobalamin deficiency through competition for dietary cobalamin in the small intestine. The objective of this study was to prospectively determine the prevalence of small bowel bacterial overgrowth in patients with documented cobalamin deficiency in a tertiary referral centre.
Methods  Patients identified with cobalamin deficiency underwent diagnostic investigations including: Endoscopy (with gastric antrum, gastric body and duodenal biopsies and duodenal aspirate), ¹⁴C-D-Xylose breath test, intrinsic factor antibody, anti-endomysial antibody and red cell folate level. 'Definite' small bowel bacterial overgrowth was defined as either a positive ¹⁴C-D-Xylose breath test or > 100 000 CFU/mL of culture of duodenal aspirate. 'Suspected' small bowel bacterial overgrowth was defined as an elevated red cell folate in the absence of supplemental folate therapy.
Results  Over a 2-year period, 62 patients with cobalamin deficiency were identified, of whom, 26 (42%) had 'definite' small bowel bacterial overgrowth, whilst a further nine (15%) had 'suspected' small bowel bacterial overgrowth. Nineteen (31%) had pernicious anaemia, and no cause for cobalamin deficiency could be found in eight (13%) patients. The diagnosis found in the remaining patients included coeliac disease (4), Crohn's Disease (1), gastric resection (2), vegan (2), homozygotes of the MTHFR gene (C677T) mutation (2), and one had enteropathy associated with common variable immunodeficiency (CVID). 'Definite' small bowel bacterial overgrowth was found to coexist with nine of the 19 cases of pernicious anaemia, two coeliac subjects, one CVID enteropathy and one patient with the MTHFR gene mutation.
Conclusion  Small bowel bacterial overgrowth is commonly associated with cobalamin deficiency.     

Pseudomembranes in reflux esophagitis

Three cases are presented in which double-contrast esophagograms revealed one or more plaquelike lesions in the distal esophagus, representing pseudomembrane formation in patients with severe reflux esophagitis. Although to our knowledge this finding has not been reported previously in the radiologic literature, pseudomembranes have been documented endoscopically in patients with reflux esophagitis and biopsy-proved Barrett esophagus. Radiologists should be aware of this finding, since these pseudomembranes may be indistinguishable radiographically from plaquelike carcinomas arising in Barrett esophagus.     

Aerobic bacterial contamination in dental materials

Current concern about disease transmission points out the need for better infection control in dentistry. The purpose of this study was to test samples of dental materials in factory-sealed containers for aerobic bacterial contamination. Multiple unopened containers of 12 different dental materials were obtained from the dental school dispensary. Samples were removed from each container and incubated at 38 degrees C in standard broth medium for 1 week. Those that exhibited visual signs of possible bacterial growth were subjected to a Gram stain for verification. The results of that test indicated that 20% to 30% of the samples of alginate, glass ionomer cement and base powders, and retraction cord contained bacterial contamination. The remaining eight dental materials exhibited no apparent bacterial growth. Thus viable aerobic organisms were found in samples from 4 of 12 dental material products.     

c-myc amplification and expression in newly established human osteosarcoma cell lines

Three cell lines were isolated from a patient with osteosarcoma of the femur. These lines were obtained from the primary neoplasm before (HTLA145) and after (HTLA161) chemotherapy and from a metastasis of the lung (HTLA195) in the same patient. The three cell lines exhibited a similar morphology in culture and formed tumors in nude mice which demonstrated a histopathology similar to that which had been observed in the patient. High expression of the genes coding for the alpha-1 and alpha-2 chain of collagen Type I was found in vitro and in s.c. tumors growing in nude mice. The c-myc protooncogene was amplified in all three cell lines and extensive expression of c-myc was found in vitro and in vivo. No heterogeneity in regard to c-myc expression in vivo was detected by in situ localization in tumors growing in nude mice.     

Zur Erstattungsfähigkeit dentinadhäsiver Versorgungen

Ohne Zusammenfassung     

Femoral capital osteonecrosis: MR finding of diffuse marrow abnormalities without focal lesions

Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head.     

力竭运动大鼠心室肌蛋白质组表达特征

目的:采用蛋白质组学技术,建立安静和递增运动负荷训练后力竭大鼠心室肌蛋白质组的差异性表达谱,初步筛选出心室肌对力竭运动产生反应的目标蛋白质。方法:实验于2007-03在湖南师范大学生命科学学院蛋白质化学与蛋白质组学国家教育部重点实验室和省级运动人体科学实验室完成。①实验分组:10只SD雄性大鼠随机分为对照组和运动组,每组5只。②实验方法:运动组经过7周的大强度递增运动负荷训练后(最后一次力竭),对两组心室肌组织的全蛋白进行双向凝胶电泳分离。结果:经图像分析,在运动组的电泳图谱上共展现蛋白质点(338±17)个,对照组展现蛋白质点(352±17)个。运动后差异表达的蛋白质点共有99个。对其中差异表达的9个蛋白质点进行质谱鉴定,共鉴定出7个蛋白质,Stress-70protein,NADH-ubiquinone oxidoreductase Mr75000subnunit,Long-chain specific acyl-CoA dehydrogenase,Tropomyosin-1alphachain在运动后"缺失",Nitrilase family,member2在运动后表达上调在5倍以上,一个相对分子质量为21000的未知蛋白在运动后表达下调在5倍以上,另外有两个点经鉴定均为Myosin-6,在运动后表达量相反。这些蛋白质属于收缩蛋白、能量代谢酶、分子伴侣等。结论:递增运动负荷训练后力竭时,大鼠心室肌蛋白质组明显地发生了反应。运动后"缺失"和下调的蛋白质点与心肌收缩的调控和能量代谢的方式转变以及细胞的应激反应有关,其中,成功筛选出6种在运动医学领域尚未涉足的、具有运动应激特点的目标蛋白质。