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Background

Ingestion of high doses of casein hydrolysate stimulates insulin secretion in healthy subjects and patients with type 2 diabetes. The effects of low doses have not been studied. The aim of this study was to assess the effect of lower doses of a casein hydrolysate on the glucose and insulin responses to an oral glucose tolerance test in patients with type 2 diabetes.

Methods

In this randomized, placebo-controlled, double-blind study, thirteen patients with type 2 diabetes (age: 58 ± 1 years) were studied.Glucose, insulin and C-peptide responses were determined after the oral administration of 0 (control), 6 or 12 g protein hydrolysate in combination with 50 g carbohydrate.

Results

Twelve grams of casein hydrolysate, but not 6 g, elevated insulin levels and decreased glucose levels post-challenge. These changes over time were not large enough to also affect the total area under the curve of glucose and insulin. C-peptide levels did not change after both treatments.

Conclusion

Ingestion of six grams of casein hydrolysate did not affect glucose or insulin responses. Intake of 12 g of casein hydrolysate has a small positive effect on post-challenge insulin and glucose levels in patients with type 2 diabetes.  相似文献   
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Salivary duct carcinoma (SDC), a rare malignancy, manifests remarkable morphologic and biologic resemblance to high-grade mammary ductal carcinoma. We contend that, similar to mammary ductal carcinoma, hormones and growth factors may play a role in SDCs. Our aim was to determine the incidence and clinical significance of the expression of several hormone and growth factor receptors and evaluate their potential in therapeutic stratification of SDC patients in the largest cohort studied to date. Eighty-four archived tumor tissue blocks were analyzed immunohistochemically for expression of estrogen receptor-beta (ERbeta), androgen receptor (AR), and proline, glutamic acid, and leucine-rich protein-1 and growth factor receptors HER-2 and epidermal growth factor receptor. The results were correlated with available pathologic, demographic, and clinical data from 59 of 84 cases. Proline, glutamic acid, and leucine-rich protein-1, ERbeta, and AR were expressed individually in 94% (71/76), 73% (57/80), and 67% (56/84) of SDCs, respectively, and coexpressed in 45% (34/75). AR was expressed significantly more often in SDCs of men than in SDCs of women [79% (35/57) vs. 33% (9/27), P<0.001]. Epidermal growth factor receptor and HER-2 were overexpressed individually in 48% (40/83) and 25% (21/84), respectively, and co-overexpressed in 12% (10/83). Survival decreased significantly in patients with lymph node metastasis (P=0.002) and positive surgical margins (P=0.006). Lack of ERbeta expression correlated with increased local and regional recurrence (P=0.05 and P=0.002, respectively). Together, these results indicate that (a) ERbeta down-regulation is associated with adverse clinical features, (b) lymph node and surgical margin status are significant survival factors, and (c) the differential expression of these hormones and growth factor receptors may assist in triaging patients with SDC for novel therapies.  相似文献   
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OBJECTIVE: Management of lower extremity arterial disease with endovascular intervention is on the rise. Current practice patterns vary widely across and within specialty practices that perform endovascular intervention. This study evaluated reimbursement and costs of different approaches for offering endovascular intervention and identified strategies to improve cost-efficiency. METHODS: The medical records of all patients admitted to a university health system during 2005 for an endovascular intervention were retrospectively reviewed. Procedure type, setting, admission status, and financial data were recorded. Groups were compared using analysis of variance, Student t test for independent samples, and chi2. RESULTS: A total of 296 endovascular interventions were completed, and 184 (62%) met inclusion criteria. Atherectomy and stenting were significantly more costly when performed in the operating room than in the radiology suite: atherectomy, dollars 6596 vs dollars 4867 (P = .002); stent, dollars 5884 vs dollars 3292, (P < .001); angioplasty, dollars 2251 vs dollars 1881 (P = .46). Reimbursement was significantly higher for inpatient vs ambulatory admissions (P < .001). Costs were lowest when the endovascular intervention was done in the radiology suite on an ambulatory basis and highest when done as an inpatient in the operating room (dollars 5714 vs dollars 12,278; P < .001). Contribution margins were significantly higher for inpatients. Net profit was appreciated only for interventions done as an inpatient in the radiology suite. Reimbursement, contribution margins, and net profit were significantly lower among private pay patients in both the ambulatory and inpatient setting. The 30-day hospital readmission after ambulatory procedures was seven patients (6%). CONCLUSIONS: Practice patterns for endovascular interventions differ considerably. Costs vary by procedure and setting, and reimbursement depends on admission status and accurate documentation; these dynamics affect affordability. Organizing vascular services within a hub will ensure that care is delivered in the most cost-efficient manner. Guidelines may include designating the radiology suite as the primary venue for endovascular interventions because it is less costly than the operating room. Selective stenting policies should be considered. Contracts with private insurers must include carve-outs for stent costs and commensurate reimbursement for ambulatory procedures, and Current Procedural Terminology (CPT; American Medical Association, Chicago, Ill) coding must be proficient to make ambulatory endovascular interventions fiscally acceptable.  相似文献   
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CONTEXT: There is increased cyclooxygenase-2 (COX-2) expression in malignant thyroid nodules compared with nonneoplastic and benign thyroid tissue. OBJECTIVE: The objective of the study was to evaluate the efficacy of celecoxib, a selective COX-2 inhibitor, in treating patients with progressive metastatic differentiated thyroid cancer (DTC) and to explore the relationship of clinical response to tumor COX-2 expression with immunohistochemistry in a subset of patients. DESIGN: The study was a prospective phase II trial with Fleming single-stage design powered at 80% with a 5% rejection error to detect more than 20% progression-free survival at 12 months. SETTING: Ambulatory patients were from tertiary referral academic medical centers. PATIENTS: Patients in the study had progressive metastatic DTC and had failed prior standard therapy. INTERVENTION: Patients were treated with celecoxib 400 mg orally twice a day for 12 months. MAIN OUTCOME MEASURE: The main outcome measure was progression-free survival at 12 months of treatment using Response Evaluation Criteria in Solid Tumors and/or serum thyroglobulin. RESULTS: Twenty-three of 32 patients experienced progressive disease or stopped therapy due to toxicity, thus fulfilling the intent-to-treat study endpoint for celecoxib failure. One patient achieved partial response, and one patient completed 12 months of therapy progression-free. The patient with partial response was on therapy along with seven other patients when the study was terminated. CONCLUSIONS: Celecoxib 400 mg orally twice per day fails to halt progressive metastatic DTC in most patients.  相似文献   
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Positive effects of dietary phytase supplementation on pig performance are observed not only when phosphorus is limiting. Improved energy utilization might be one explanation. Using indirect calorimetry, phytase-induced changes in energy metabolism were evaluated in young piglets with adequate phosphorus intake. Eight replicates of 8 group-housed barrows each were assigned to either a control or a phytase-supplemented diet [1500 phytase units (FTU)/kg feed]. Piglets were fed a restricted amount of the control or phytase diet. The diets were made limiting in energy content by formulating them to a high digestible lysine:DE ratio. Fecal nutrient digestibility, portal blood variables, organ weights, and apparent absorption and urinary excretion of ash, Ca, P, Na, K, Mg, Cu, and Fe, were also measured. A model was developed to estimate energy required for absorption and excretion, which are partly active processes. Phytase tended to improve energy digestibility (P = 0.10), but not its metabolizability. Energy retention and heat production were not affected. At the end of the 3-wk period, pancreas weight (P < 0.05) and blood pH were lower (P < 0.01), and CO(2) pressure was higher (P < 0.01) due to phytase. This suggests that phytase reduced energy expenditure of the digestive tract, and increased metabolic activity in visceral organs. The potential increases in energy retention due to phytase were counterbalanced by increased energy expenditures for processes such as increased mineral absorption (for most P < 0.05), and their subsequent urinary excretion. Energy costs of increased absorption of nutrients, and deposition and excretion of minerals was estimated as 4.6 kJ/(kg(0.75) . d), which is 1% of the energy required for maintenance. The simultaneous existence of both increases and decreases in heat production processes resulted in the absence of a net effect on energy retention.  相似文献   
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