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1.
The New Zealand obese mouse (NZO/Hl) is characterised by hereditary obesity and type-2 diabetes, including insulin resistance, hyperinsulinaemia, and glucose intolerance. In other diabetic models, it has been revealed that the proper functioning of the glucose transporter isoform 2 (GLUT2) is essential for adequate secretion of insulin. The aim of this study was to compare the distribution of islet cells and GLUT2, as well as the expression of GLUT2-mRNA, in the pancreas of NZO mice and metabolically unimpaired NMRI (Naval Medical Research Institute) mice. Pancreas tissue was obtained from different stages of development. For molecular determination of the expression level of GLUT2-mRNA, total-RNA was extracted from the pancreas and analysed by quantitative real-time RT-PCR. All investigated NZO mice displayed increased weight, elevated hyperinsulinaemia, and slightly enhanced blood glucose levels compared with the NMRI control mice. By means of immunofluorescence microscopy drastically reduced insulin levels were detected, which might be compensated by the observed islet cell hyperplasia and hypertrophy. Furthermore, the normally peripheral localisation of the alpha-cells within islets was disturbed. By contrast, there were no changes in somatostatin cell distribution. However, considerable differences appeared with regard to GLUT2: whereas the beta-cells of NMRI mice showed dense immunostaining of the GLUT2 transporter on the cell surface, in all age groups of NZO mice, GLUT2 on the plasma membranes was reduced and dispersed in the cytoplasm. These findings agree with the molecular biological results, which displayed decreased mRNA-expression of GLUT2. In summary, the observed alteration of islet morphology and of GLUT2 expression in diabetic mice complements our previous results from a superfusion protocol and further clarifies the mechanisms of diabetogenesis in NZO mice.  相似文献   
2.
Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.  相似文献   
3.
Wilson disease (WD) is a rare inherited autosomal recessive disorder caused by a defect in a metal transporting P-type ATPase, resulting in copper overload in various tissues and cells. The aim was to assess both the phenotype in Brazilian WD patients and the corresponding ATP7B genotype. Sixty subjects belonging to 46 pedigrees diagnosed as WD were included in this study. Direct sequencing of all 21 exons within ATP7B and their flanking introns was performed. Demographic, clinical, laboratory and histopathological data at the time of diagnosis were obtained. We identified twenty-five mutations, twelve of them reported for the first time. The c.3402delC mutation had the highest allelic frequency (30.8%), followed by the c.2123T>C (p.L708P) (16.7%). Exons 8 and 15 were the site of 62.5% of the mutations. The common European mutation c.3207C>A (p.H1069Q) was not present at all. Phenotype varied greatly among individuals with the same ATP7B genotype. Our data confirm the heterogeneity of ATP7B genotype in Brazilian WD patients. The mutational spectrum is compatible with the Brazilian history of Mediterranean immigration; however, new mutations, and different frequencies and phenotype associated with the previously known mutations characterize this population. Exons 8 and 15 should be preferentially screened in WD cases from Brazil. Phenotype variation among subjects with the same ATP7B genotype suggests that modifying factors play an additional role in the pathogenesis of WD.  相似文献   
4.
Introduction: Primary open-angle glaucoma (POAG) is a leading cause of visual impairment worldwide and a complex genetic disorder that affects mostly adults. Mutations in the MYOCILIN (MYOC) and OPTINEURIN genes account for rare forms with a Mendelian inheritance and for <5% of all POAG cases. The CYP1B1 gene, a member of the cytochrome P450 gene family, is a major cause of primary congenital glaucoma (PCG), a rare and severely blinding disease with recessive inheritance. However, CYP1B1 mutations have also been associated with cases of juvenile-onset glaucoma in some PCG families or shown to modify the age of onset of glaucoma linked to a MYOC mutation in a large family.

Objective: To investigate the role of CYP1B1 mutations in POAG predisposition, irrespective of the presence of a MYOC mutation.

Methods and subjects: CYP1B1 coding region variation was characterised by denaturing high performance liquid chromatography (DHPLC) and sequencing in 236 unrelated French Caucasian POAG patients and 47 population-matched controls.

Results: Eleven (4.6%) patients carried one or two mutated CYP1B1 gene(s) and no MYOC mutation. They showed juvenile or middle-age onset of disease (median age at diagnosis, 40 years, range 13–52), significantly earlier than in non-carrier patients. Apart from one, all mutations detected in POAG patients were previously associated with PCG.

Conclusion: CYP1B1 mutations might pose a significant risk for early-onset POAG and might also modify glaucoma phenotype in patients who do not carry a MYOC mutation.

  相似文献   
5.
BACKGROUND: Early authors described hypomanic symptoms as mixed features in depressive episode, but this syndrome has not been sufficiently explored in previous studies. METHODS: 958 consecutive depressed patients were assessed by using a standardized method in terms of 43 psychiatric symptoms at hospitalization. RESULTS: A principal component analysis, followed by varimax rotation, extracted six interpretable factors: typical vegetative symptoms, depressive retardation/loss of feeling, hypomanic syndrome, anxiety, psychosis, and depressive mood/hopelessness. The extracted factor structure was relatively stable among several patient groups. There was no evidence that the hypomanic factor was exaggerated by antidepressant pretreatments before hospitalization. Bipolar diagnoses were associated with higher scores on depressive retardation and hypomanic symptoms, and a lower score on anxiety. LIMITATIONS: Psychiatric syndromes and their interrelationships, found in the present study, may be strongly influenced by the rating instrument used. The sample of this study was depressed inpatients. The results should not be generalized for depressed outpatients or epidemiological depressed populations. CONCLUSIONS: Hypomanic symptoms, as characterized by the flight of ideas, racing thought, increased drive, excessive social contact, irritability, and aggression are a salient syndrome in acutely ill depressed patients, lending support to the factor validity of mixed depression. The symptoms may not be related to pretreatments with antidepressants, or comorbidity of substance abuse, suggesting that they reflect various natural phenomenological manifestations of depressive episodes. Anxiety is unlikely to play a major role in the core phenomenological features of mixed depression. Hypomanic symptoms during a depressive episode were more represented in bipolar disorders, which may serve for further clarifications of latent bipolarity in unipolar depression, and prediction of switch into maniform states under biological depression treatments.  相似文献   
6.
Interest in possible microbiological causes of gastritis has increased significantly since the discovery of Helicobacter pylori (Hp). Recently a spiral bacterium named Helicobacter heilmannii (Hh) was described in association with chronic gastritis in adult and pediatric patients. Comparisons between these two organisms, as well as the literature on Hh, have also been reviewed. The incidence of Hh gastritis is far lower than that of Hp gastritis. Concomitant infections by Hh and Hp are very rare. It is very probable that Hh gastritis is transmitted from domestic animals or pets to humans. The frequency of Hh gastritis (11/6059 cases, 0.18%) in authors' material was similar to that reported in Western Europe. The role of touch cytology has been becoming more and more significant recently in the diagnosis of mucosal infections of the GIT.  相似文献   
7.
Yoon HJ  Kim H  Kim HL  Lee SG  Zheng SH  Shin JH  Lim CS  Kim S  Lee JS  Lee DS  Kim YS 《Clinical genetics》2002,62(2):128-134
In order to investigate the interdependent action of the insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene and polymorphism in exon 11 (C1136-->T; Ala379Val) of the platelet-activating factor acetylhydrolase (PAF-AH) gene, which encodes a functional antagonist of PAF, on the progression of immunoglobulin A (IgA) nephropathy, we analysed both polymorphisms in patients with primary IgA nephropathy, who were followed-up for longer than 3 years. During the follow-up (87.3 +/- 50.0 months), the disease progressed in 38 of the 191 patients (19.9%). The D allele of the ACE gene in the absence of the T allele of the PAF-AH gene did not affect the prognosis [odds ratio (OR), 3.6; 95% confidence interval (CI), 0.8-16.4] and neither did the T allele in the absence of the D allele (OR, 3.0; 95% CI, 0.4-24.2). However, the presence of both was a significant prognostic factor (OR, 6.6; 95% CI, 1.4-31.3). After adjusting for other risk factors, the presence of both proved to be an independent risk factor (OR, 4.5; 95% CI, 1.6-12.7). These results suggest that the interdependent effects of ACE and PAF-AH polymorphisms on the progression of IgA nephropathy might be more important than the effect of the individual polymorphisms.  相似文献   
8.
Hu WH  Lu J  Lei YP  Chen BW  Tang WR  Cun YN  Dong YL  Tan SJ  Yu HJ  Xiao CJ 《Tissue antigens》2005,65(3):289-292
A sequencing-based typing of human leukocyte antigen-DPB1 (HLA-DPB1) gene was carried out in 37 unrelated healthy individuals from the Yunnan Lisu ethnic minority. A total of 12 DPB1 alleles, in which DPB1*1301 (33.3%), DPB1*0402 (16.6%), DPB1*040101 (13.8%), and DPB1*0501 (11.1%) were highly predominant, were found, and allele DPB1*200102 was found for the first time in a Chinese population. A dendrogram constructed by neighbor-joining method showed that the Lisu ethnic group belongs to East Asian cluster.  相似文献   
9.
We asked whether dynamization of externally fixed diaphyseal fractures could improve bone healing in comparison to rigid fixation of fractures having similar remaining gap sizes. To answer this question we evaluated metatarsal osteotomies in 12 sheep. The osteotomy with a 0.6-mm gap was stabilized with a specially designed high bending and torsional stiffness external ring fixator. Osteotomies in six sheep were stabilized rigidly (axial movement < 0.06 mm) or dynamically (axial movement 0.15-0.34 mm). The cyclical axial interfragmentary movement was caused by the load-bearing of the operated limb. With increasing healing time, the initially allowed movement was decreased by callus formation around the osteotomy. The reduction in interfragmentary movement was measured and monitored by a linear variable displacement transducer at the external fixator and a telemetry system. After 9 weeks the sheep were sacrificed and the healed bones were investigated biomechanically and histomorphologically. Compared to the rigidly fixed osteotomies, the dynamized osteotomies showed significantly (P < 0.05) greater (+41%) callus formation and 45% greater tensile strength of the newly formed bone in the cortical osteotomy gap. Histological analysis indicated that the effect of dynamization occurred mainly after the 5th week. RELEVANCE: From these results we conclude that dynamic fixation of diaphyseal gaps is advantageous in comparison to stable external fixation.  相似文献   
10.
We included in a prospective study of a standardized indomethacin protocol 134 consecutive patients undergoing primary cementless endoprosthetic hip replacement between January and June 1990. Periarticular heterotopic ossification (HO) was graded according to the Arcq classification (grades 0 to III). At final follow-up, all patients were analyzed clinically and radiographically for HO and aseptic loosening. A similar group of 44 patients (mean age of 64 years, range 38-82 years) undergoing total hip replacement (THR) with the same prosthesis and technique in 1987 did not receive HO prophylaxis and served as a control group. The average age of the 134 prophylaxis patients was 66.5 years (range 32-85 years), and the average follow-up was 65 months (range 60-71 months). Thirty patients (25%) were lost to final follow-up (19 died, 10 unknown, 1 amputation). In the study group, 77% had HO grade 0, while none had HO grade III, compared with 18% HO grade 0 and 16% HO grade III in the control group. These differences were statistically significant (P = < 0.001). At a minimum of 60 months follow-up, clinical and radiographic evaluation revealed no aseptic loosening in the study group: 4 cases of prosthesis subsidence during the first year did not progress. In the control group, there was a higher incidence of radiolucency around the femoral component, and one patient met all criteria for radiographic evidence of aseptic loosening. Statistical analysis revealed no significant difference between the two groups (P = 0.104). Based on our clinical and radiological results, indomethacin does not inhibit stable bony integration of the femoral component.  相似文献   
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