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41.
OBJECTIVE: Defects in glycosylation of alpha-dystroglycan are associated with several forms of muscular dystrophy, often characterized by congenital onset and severe structural brain involvement, collectively known as dystroglycanopathies. Six causative genes have been identified in these disorders including fukutin. Mutations in fukutin cause Fukuyama congenital muscular dystrophy. This is the second most common form of muscular dystrophy in Japan and is invariably associated with mental retardation and structural brain defects. The aim of this study was to determine the genetic defect in two white families with a dystroglycanopathy. METHODS: The six genes responsible for dystroglycanopathies were studied in three children with a severe reduction of alpha-dystroglycan in skeletal muscle. RESULTS: We identified pathogenic fukutin mutations in these two families. Affected children had normal intelligence and brain structure and shared a limb girdle muscular dystrophy (LGMD) phenotype, had marked elevation of serum creatine kinase, and were all ambulant with remarkable steroid responsiveness. INTERPRETATION: Our data suggest that fukutin mutations occur outside Japan and can be associated with much milder phenotypes than Fukuyama congenital muscular dystrophy. These findings significantly expand the spectrum of phenotypes associated with fukutin mutations to include this novel form of limb girdle muscular dystrophy that we propose to name LGMD2L.  相似文献   
42.

OBJECTIVE

To determine the role of hepatocyte growth factor (HGF)/c-Met on β-cell survival in diabetogenic conditions in vivo and in response to cytokines in vitro.

RESEARCH DESIGN AND METHODS

We generated pancreas-specific c-Met-null (PancMet KO) mice and characterized their response to diabetes induced by multiple low-dose streptozotocin (MLDS) administration. We also analyzed the effect of HGF/c-Met signaling in vitro on cytokine-induced β-cell death in mouse and human islets, specifically examining the role of nuclear factor (NF)-κB.

RESULTS

Islets exposed in vitro to cytokines or from MLDS-treated mice displayed significantly increased HGF and c-Met levels, suggesting a potential role for HGF/c-Met in β-cell survival against diabetogenic agents. Adult PancMet KO mice displayed normal glucose and β-cell homeostasis, indicating that pancreatic c-Met loss is not detrimental for β-cell growth and function under basal conditions. However, PancMet KO mice were more susceptible to MLDS-induced diabetes. They displayed higher blood glucose levels, marked hypoinsulinemia, and reduced β-cell mass compared with wild-type littermates. PancMet KO mice showed enhanced intraislet infiltration, islet nitric oxide (NO) and chemokine production, and β-cell apoptosis. c-Met-null β-cells were more sensitive to cytokine-induced cell death in vitro, an effect mediated by NF-κB activation and NO production. Conversely, HGF treatment decreased p65/NF-κB activation and fully protected mouse and, more important, human β-cells against cytokines.

CONCLUSIONS

These results show that HGF/c-Met is critical for β-cell survival by attenuating NF-κB signaling and suggest that activation of the HGF/c-Met signaling pathway represents a novel strategy for enhancing β-cell protection.Type I diabetes is an autoimmune disease that results from cellular cytotoxicity leading to selective and progressive destruction of insulin-secreting cells (13). Many growth factors known to control cell growth and survival in physiologic and pathologic conditions are expressed in the pancreas and could potentially participate in an autocrine/paracrine fashion in the final fate of β-cells in an autoimmune environment. Overexpression of IGF-1, transforming growth factor-β, or granulocyte macrophage-colony stimulating factor ameliorates islet infiltration and β-cell death in mouse models of increased islet inflammation and diabetes (46). However, the role of endogenous pancreatic growth factors in type I diabetes has not been examined. Because growth factors can locally affect β-cell survival, neogenesis, and regeneration, and modulate chemokine production and immune responses, alterations in the level/activation of growth factor signaling pathways might contribute to the delay/acceleration of the onset of diabetes.Hepatocyte growth factor (HGF)/c-Met signaling pathway participates in the control of multiple biological functions, including development, proliferation, survival, regeneration, and branching morphogenesis (7). HGF binds with high affinity to, and induces the dimerization of, c-Met, its transmembrane tyrosine kinase receptor (8). Deletion of exon 16 of the c-Met gene, which encodes Lys1108 (ATP binding site), essential for the kinase activity of this receptor, in knockout mice results in embryonic lethality (9). These mice display a phenotype identical to HGF knockout mice (10). Both HGF and c-Met are expressed in the pancreas; HGF localizes to endothelial, islet, and mesenchymal cells, and c-Met is expressed in islet, ductal, and pancreatic progenitor cells (1114). Conditional ablation of the c-Met gene in mouse β-cells using RIP-Cre and lox-c-Met mice leads to deficient insulin secretion without alteration of β-cell mass (12,13). On the other hand, HGF overexpression in the β-cell of transgenic mice increases β-cell replication, mass, and function (15,16). Furthermore, HGF improves islet graft survival in animal models of diabetes (1719). HGF positively influences autoimmune responses, reducing the severity of autoimmune myocarditis and arthritis (20,21). HGF also downregulates airway and kidney inflammation, and inflammatory bowel disease (2224). Whether HGF plays a role in autoimmune diabetes is unknown.To address the function of c-Met in the development, growth, and maintenance of β-cells under physiologic conditions, as well as its role in β-cell survival and response to injury in vivo, we generated pancreas-specific c-Met-null (PancMet KO) mice. We report that although c-Met is dispensable for normal β-cell growth and function under basal conditions, it is critically important for β-cell survival in diabetogenic conditions. β-Cell survival is dramatically worsened in the absence of HGF/c-Met signaling, resulting in accelerated diabetes onset. These observations also apply to human β-cells, underscoring a therapeutic opportunity for the HGF/c-Met signaling pathway in human diabetes.  相似文献   
43.
OBJECTIVES: Hemophilia is a sex-linked condition affecting about 1 of every 5000 males in the United States. The management of children with hemophilia can be improved with regular intravenous infusion of factor VIII or IX, thus preventing crippling and sometimes fatal hemorrhage. Maintaining this vital intravenous access is often hampered by gradual loss of superficial veins or repeated central catheter sepsis and thrombosis. This study reviewed an experience with arteriovenous fistula in selected hemophilia patients with limited venous access. METHODS: Consecutive patients operated on between October 2000 and July 2006 for venous access with the creation of an arteriovenous fistula were reviewed. They were selected because of repeated problems with other venous access. Patency, ease of use, duplex scan derived brachial artery diameter, and arm length were assessed. RESULTS: During a 69-month period, 10 arteriovenous fistulas (five brachial artery-basilic vein fistulas, 5 brachial artery-cephalic vein fistulas) were created for nine patients. The patients were a median age of 5.5 years (range, 1 to 27 years), and all were <13 except the 27-year-old patient. There were no postoperative hematomas requiring evacuation. One arteriovenous fistula failed to mature and was redone in the opposite arm, which subsequently occluded after 13 months. Of the mature fistulas, patency was 100% at 1 year, 80% (4/5) at 3 years, and 75% (3/4) at 4 years, with mean follow-up of 22 months. Brachial artery diameter increased in the involved arm by a ratio of 1.95 (range, 1.51 to 2.5) compared with the opposite arm. Arm length disparity was increased by 0.5 cm (range, 0.8 to 1.5 cm) in the involved arm. All fistulas allowed good access at home by a care provider. CONCLUSIONS: For hemophilia patients with compromised venous access, arteriovenous fistulas provide good early patency. Brachial artery diameter and arm length require continued follow-up.  相似文献   
44.

Background

Hypocalcemia and nerve injury are the most severe complications after thyroid surgery. The duration of surgery has not been previously considered as a risk factor for postoperative complications in patients undergoing total thyroidectomy. We sort to investigate the influence of prolonged surgery on postoperative complications in patients undergoing total thyroidectomy.

Methods

We hypothesized that a threshold of?>?120 minutes of surgical time could represent a surrogate marker for postoperative complications in patients undergoing total thyroidectomy for benign thyroid disorders. The study population was divided into two groups based on the median duration of surgery (120 min): group I?≤?120 minutes (control group), group II?>?120 minutes (study group). The charts of eligible patients undergoing total thyroidectomy within a six-year period from January 1st 2006 to December 31st 2012 were reviewed. The primary outcomes included the rates postoperative hypocalcemia and recurrent laryngeal nerve palsy. The secondary outcomes included the rates of postoperative hemorrhage, wound dehiscence and length of hospital stay.

Results

305 cases of thyroidectomy were included for analysis; 130 (42.6%) control group and 175 (57.4%) study group. Transient (15.4% vs 19.4%) and permanent (3.8% vs. 2.9%) hypocalcemia were recorded in control and study group respectively. The incidence of nerve palsy was 1.5% in the control group and 1.4% in the study group. The mean length of postoperative hospital stay was 3d in both groups. There was no significant difference amongst both groups with regard to postoperative bleeding (p?=?0.57) and wound dehiscence (p?=?0.31). Prolonged surgery (> 120 min) was not identified as a risk factor for increased postoperative complication.

Conclusion

Prolonged duration of surgery?>?120 minutes is not a surrogate marker for postoperative complications in patients undergoing total thyroidectomy.
  相似文献   
45.

Purpose

To evaluate the effect of a multidisciplinary rehabilitation programme on disability, kinesiophobia, catastrophizing, pain, quality of life and gait disturbances in patients with chronic low back pain (CLBP).

Methods

This was a parallel-group, randomised, superiority-controlled pilot study in which 20 patients were randomly assigned to a programme consisting of motor training (spinal stabilising exercises plus usual-care) and cognitive–behavioural therapy (experimental group, 10 subjects) or usual-care alone (control group, 10 subjects). Before treatment, 8 weeks later (post-treatment), and 3 months after the end of treatment, the Oswestry Disability Index, the Tampa Scale for Kinesiophobia, the Pain Catastrophizing Scale, a pain numerical rating scale, and the Short-Form Health Survey were assessed. Spatio-temporal gait parameters were also measured by means of an electronic walking mat. A linear mixed model for repeated measures was used for each outcome measure.

Results

The programme had significant group (p = 0.027), time (p < 0.001), and time-by-group interaction (p < 0.001) effects on disability, with the experimental group showing an improvement after training of about 61 % (25 % in the control group). The analyses of kinesiophobia, catastrophizing, and the quality of life also revealed significant time, group, and time-by-group interaction effects in favour of the experimental group, and there was a significant effect of time on pain. Both groups showed a general improvement in gait parameters, with the experimental group increasing cadence significantly more.

Conclusion

The multidisciplinary rehabilitation programme including cognitive–behavioural therapy was superior to the exercise programme in reducing disability, kinesiophobia, catastrophizing, and enhancing the quality of life and gait cadence of patients with CLBP.  相似文献   
46.
47.
Physical exercise stimulates cell proliferation in the adult dentate gyrus and facilitates acquisition and/or retention of hippocampal‐dependent tasks. It is established that regular physical exercise improves cognitive performance. However, it is unclear for how long these benefits last after its interruption. Independent groups of rats received both free access to either unlocked (EXE Treatment) or locked (No‐EXE Treatment) running wheels for 7 days, and daily injections of bromodeoxyuridine (BrdU) in the last 3 days. After a time delay period of either 1, 3, or 6 weeks without training, the animals were tested in the Morris water maze (MWM) either in a working memory task dependent on hippocampal function (MWM‐HD) or in a visible platform searching task, independent on hippocampal function (MWM‐NH). Data confirmed that exposure of rats to 7 days of spontaneous wheel running increases cell proliferation and neurogenesis. In contrast, neurogenesis was not accompanied by significant improvements of performance in the working memory version of the MWM. Longer time delays between the end of exercise and the beginning of cognitive training in the MWM resulted in lower cell survival; that is, the number of novel surviving mature neurons was decreased when this delay was 6 weeks as compared with when it was 1 week. In addition, data showed that while exposure to the MWM‐HD working memory task substantially increased survival of novel neurons, exposure to the MWM‐NH task did not, thus indicating that survival of novel dentate gyrus neurons depends on the engagement of this brain region in performance of cognitive tasks. © 2015 Wiley Periodicals, Inc.  相似文献   
48.
The study discusses the construct of spontaneity and its causal relationship with psychological well-being. It develops a preview phase of validation of the SAI-R and its correlation with the Clinical Outcomes for Routine Evaluation-Outcome Measure (CORE-OM) and the Beck Depression Inventory (BDI-II) and assumes the hypothesis that a high level of spontaneity is correlated negatively with low level of well-being and positively with depression. The research involved Italian and Austrian participants, consisting of 166 Italian and 146 Austrian university students. The findings suggested a causal relationship between low spontaneity and psychological suffering. The results obtained confirm the hypothesized model, showing significant negative causal relationship. The verification of this theoretical model on non-clinical samples allows us to set the ground for future use in clinical samples. Furthermore, this result encourages the development of further research into the use of SAI-R.  相似文献   
49.
The aim of this study was to identify at species level and to investigate the antibiotic susceptibility of oral streptococcal strains isolated from 100 pus samples collected from Romanian patients with different odontogenic infections. The isolates were identified at species level using the Rapid ID 32 STREP system and their susceptibility was testing by the Etest, against: penicillin G, ampicillin, erythromycin, clindamycin and tetracycline. For the investigation of erythromycin resistance phenotype the disk diffusion test was used. The isolates belonged to several species, with Streptococcus anginosus and Streptococcus oralis predominating. Reduced susceptibility to beta-lactam antibiotics was found only among the isolates belonging to S. mitis and S. sanguinis groups. Resistance to erythromycin was detected among all species, except for: S. constellatus, S. intermedius and S. gordonii, and the M phenotype was established, while resistance to tetracycline was detected within all species but S. gordonii. In contrast, clindamycin was fully active. As most odontogenic infections are mixed infections, often involving strictly anaerobic bacteria, which are frequently beta-lactamase producers, the association of a penicillin and a beta-lactamase inhibitor, like Amoxiclav, is recommended when the antimicrobial treatment is necessary.  相似文献   
50.
Even though very precise at describing pelvic organ position, our criticism to the Pelvic Organ Prolapse Quantification (POP-Q) system is its limited ability to quantify the prolapse itself, since it still classifies prolapse into four stages, almost the same way as Baden and Walker (Clin Obstet Gynecol 15(4):1070-1072, 1972) did in 1972. As a result, the same grade can include a wide prolapse intensity range. The objective of this study was to assess inter-observer reliability in the Pelvic Organ Prolapse Quantification Index (POP-Q-I; Lemos et al., Int Urogynecol J 18(6):609-611, 2007) on a prospective randomized trial. Fifty consecutive women were prospectively examined by two members of the urogynecology staff, blinded to each other's results. Spearman's rank correlation was used to assess inter-observer reliability. Excellent correlation coefficients were observed, with an overall coefficient of 96.5% (CI: 0.889-1.042; p < 0.0001). The POP-Q-I is a method that makes POP research more efficient by directly measuring prolapse as a continuous variable, which is statistically more powerful than the categorical variables proposed by the POP-Q system. This study suggests that the POP-Q-I is applicable to clinical POP research.  相似文献   
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