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81.
Background: Gastric electrical stimulation (GES) is currently investigated for the treatment of obesity. The TANTALUS System delivers gastric contractility modulation (GCM) signals in synchrony with gastric slow waves, resulting in significant augmentation of gastric contractions during food intake. We hypothesized that such modulation of contractile activity may affect gastric emptying and plasma ghrelin levels. Aim: To test the effect of GCM of the gastric antrum on gastric emptying of solids and ghrelin levels. Methods: 12 obese subjects were implanted with 2 pairs of antral electrodes and an implantable pulse generator (IPG, TANTALUS TM) Gastric emptying test (GE) for solids was performed twice, on separate days, in each subject, starting few weeks after implantation: 1) control, before the start of stimulation, and 2) with stimulation, after device was turned on. Blood samples for ghrelin, were taken at baseline, and at 15, 30, 60 and 120 min after the test meal. Results as mean + SD, analysis by t‐test and p < 0.05. Results: 11 females, 1 male, age: 39.1 ± 8.9 years, BMI: 41.6 ± 3.4, 3 subjects with type 2 diabetes. One diabetic patient did not complete GE test because of technical issues. GCM significantly accelerated gastric emptying: retention at 2 hours 18.7 ± 12.2% vs. 31.9 ± 16.4%, stimulation vs. control respectively, p = 0.008. T 1/2 78.3 ± 23.5 vs. 95 ± 31.7 min, stimulation vs. control respectively, p = 0.04. Mean results for gastric emptying were within normal at both baseline and stimulation. Meal ingestion induced only minimal, insignificant reduction in ghrelin levels. There was no significant difference in AUC of ghrelin between control and stimulation. Conclusions: After GCM stimulation, there is significant acceleration of gastric emptying of solids in obese patients, without affect on ghrelin levels. The obese subjects did not exhibit the significant, meal‐induced reduction in ghrelin.   相似文献   
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Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are responsible for autosomal recessive proximal spinal muscular atrophy (SMA). SMN orthologues have been identified in the nematode worm Caenorhabditis elegans and the yeast Schizosaccharomyces pombe but, to date, no human paralogues have been described. Here we describe identification and characterization of an SMN-related protein (SMNrp) gene that encodes a novel protein of 239 amino acids, which has recently been identified as a constituent of the spliceosome complex and designated SPF30. Significant similarity to the SMN protein is apparent only within a central region of SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped to chromosome 10q23. It is differentially expressed, with abundant levels in skeletal muscle. An exclusively nuclear localization for SMNrp in cultured cells and muscle sections was revealed using GFP fusion constructs and thereafter confirmed with a polyclonal antibody raised against SMNrp. Overexpression of SMNrp as a fusion protein in HeLa cells in culture induced dose-dependent apoptosis with positive TUNEL staining. In addition to a possible role for this protein as a pro-apoptotic factor, SMN and its related protein share significant similarities in sequence and cellular function.   相似文献   
83.
Human chromosome 11p15.5 and distal mouse chromosome 7 include a megabase-scale chromosomal domain with multiple genes subject to parental imprinting. Here we describe mouse and human versions of a novel imprinted gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a predicted multi-membrane-spanning protein similar to bacterial and eukaryotic polyspecific metabolite transporter and multi- drug resistance pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues with metabolite transport functions, including liver, kidney, intestine, extra-embryonic membranes and placenta, and there is strongly preferential expression of the maternal allele in various mouse tissues at fetal stages. In post-natal tissues there is persistent expression, but the allelic bias attenuates. An allelic expression bias is also observed in human fetal and post-natal tissues, but there is significant interindividual variation and rare somatic allele switching. The fact that Impt1 is relatively repressed on the paternal allele, together with data from other imprinted genes, allows a statistical conclusion that the primary effect of human chromosome 11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative repression of genes on the paternal homolog. Dosage regulation of the metabolite transporter gene(s) by imprinting might regulate placental and fetal growth.   相似文献   
84.
Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
85.
Confidential enquiries into poor perinatal outcomes have identified deficiencies in team working as a common factor and have recommended team training in the management of obstetric emergencies. Isolated aviation-based team training programmes have not been associated with improved perinatal outcomes when applied to labour ward settings, whereas obstetric-specific training interventions with integrated teamwork have been associated with clinical improvements. This commentary reviews obstetric emergency training programmes from hospitals that have demonstrated improved outcomes to determine the active components of effective training. The common features identified were: institution-level incentives to train; multi-professional training of all staff in their units; teamwork training integrated with clinical teaching and use of high fidelity simulation models. Local training also appeared to facilitate self-directed infrastructural change.  相似文献   
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Current management of chest-wall tumors   总被引:2,自引:0,他引:2  
Chest-wall resection can be performed with low morbidity and mortality rates and remains the primary treatment for most chest-wall tumors. However, some lesions are best treated with a multimodality approach including preoperative chemotherapy. Therefore, pretreatment tissue diagnosis is essential in planning. The biopsy should be done at the medical center where the definitive treatment will be undertaken, and frequently, a needle biopsy will be sufficient. Osteosarcoma, rhabdomyosarcoma, Ewing's sarcoma, and other small-cell sarcomas are sensitive to chemotherapy, which should be given preoperatively, continued postoperatively, and modified according to the tumor response. Chondrosarcomas and most adult soft-tissue sarcomas are well controlled by primary excision and selective use of adjuvant irradiation. Better systemic and local therapy is needed for the recurrent soft-tissue sarcomas and the aggressive unclassified sarcomas. Chest-wall resection continues to play a primary role in the management of locally and regionally recurrent breast cancer but is best combined with systemic chemotherapy. Chest-wall resection can provide a long disease-free survival in patients with isolated metastases from sarcomas or carcinomas. In addition, significant palliation can be afforded patients with symptomatic chest-wall metastases and a shortened life expectancy.  相似文献   
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