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81.
82.
Glucagon like peptide 1 (GLP-1) is an incretin hormone released as a bioactive peptide from intestinal L-cells in response to eating. It acts on target cells and exerts several functions as stimulating insulin and inhibiting glucagon. It is quickly deactivated by the serine protease dipeptidyl peptidase IV (DPP-IV) as an important regulatory mechanism. GLP-1 analogues are used as antidiabetic drugs in patients with type 2 diabetes. We served patients with cystic fibrosis (CF, n=29), cystic fibrosis related diabetes (CFRD, n=19) and healthy controls (n=18) a standardized breakfast (23 g protein, 25 g fat and 76 g carbohydrates) after an overnight fasting. Blood samples were collected before meal as well as 15, 30, 45 and 60 min after the meal in tubes prefilled with a DPP-IV inhibitor. The aim of the study was to compare levels of GLP-1 in patients with CF, CFRD and in healthy controls. We found that active GLP-1 was significantly decreased in patients with CF and CFRD compared to in healthy controls (p<0.01). However, levels in patients with CFRD tended to be lower but were not significantly lower than in patients with CF without diabetes (p=0.06). Total GLP-1 did not differ between the groups, which points to that the inactive form of GLP-1 is more pronounced in CF patients. The endogenous insulin production (measured by C-peptide) was significantly lower in patients with CFRD as expected. However, levels in non-diabetic CF patients did not differ from the controls. We suggest that the decreased levels of GLP-1 could affect the progression toward CFRD and that more studies need to be performed in order to evaluate a possible treatment with GLP-1 analogues in CF-patients.  相似文献   
83.

Purpose

The aim of this pilot study was to describe the hydration and nutritional status of a cohort of elderly dialysis patients and to explore the association between these parameters and the quality of life (QoL).

Methods

All patients over 75?years of age being in chronic dialysis by January 2008 at 3 dialysis units (n?=?34) were asked to participate in this pilot study, 24 patients were entered. Hydration status was assessed by bioimpedance spectroscopy (BIS) and nutritional status by the subjective global assessment (SGA), BIS, anthropometric measures and biochemical parameters. Based on these assessments the patients were classified as being cachectic or not according to newly defined criteria. QoL was measured using the SF-36.

Results

The results showed cachexia in 6 (25?%), 37.5?% had a body mass index below 24, whereas according to SGA 91?% were malnourished. BIS showed low lean tissue index in 46?% and overhydration in 35?% of the patients. Compared to non-cachectic and normohydrated, cachectic and overhydrated patients reported consistently poorer QoL. For cachectic patients, the differences were clinically significant for all SF-36. BIS was easily applicable when used before dialysis.

Conclusions

The high frequency of nutritional deficits in this study calls for more attention to nutritional status in elderly dialysis patients. There is a need for a general agreement on how nutritional status should be assessed and reported, both in clinics and in research.  相似文献   
84.
OBJECTIVE: Aortic valve replacement for aortic valve stenosis (AS) and regurgitation (AR) in patients with severe left ventricular (LV) dysfunction contains an increased risk. Few data are available on the outcome of such patients. METHODS: Fifty-five consecutive patients with severe LV dysfunction (ejection fraction, EF; <30%) and aortic valve replacement for AS (n=35) or AR (n=20) were investigated between 1994 and 2001. EF was 25+/-5%, mean transvalvular gradient 26+/-6mmHg (AS), aortic valve area 0.66+/-0.18cm(2) (AS), cardiac index (CI) 2.4+/-0.9l/min/m(2), enddiastolic LV diameter (LVEDD) 64+/-8mm and endsystolic LV diameters (LVESD) was 55+/-3mm. Ninety percent of patients were in New York Heart Association (NYHA) functional class III/IV at admission to the hospital. Concomitant coronary artery bypass grafts (CABG) were performed in 14 patients. Follow-up examinations including chest X-ray, echocardiography, exercise testing, were performed among survivors. RESULTS: The survival rates for AS were: 1-year 76%, 2-year 68.8%, 5-year 64.2%; for AR: 1-year 94.4%, 2-year 86.5%, 5-year 74.2%. NYHA functional class improved from 90% in class III/IV to 45 (AR group) and 24% (AS group) at follow-up (P<0.02). The LVEDD decreased to 54+/-8mm after 1 year. The EF improved to 38+/-4 (AR group) and 40+/-5% (AS group) at follow-up. CONCLUSIONS: Despite severe LV dysfunction, increased 1-year mortality especially in the AS group, aortic valve replacement was associated with improved functional status, symptoms and EF in both groups and in most patients. We, therefore, conclude that aortic valve replacement in patients with severe LV dysfunction can be performed with acceptable risk.  相似文献   
85.
BACKGROUND: Many studies have demonstrated that either glutamate -methyl-d-aspartate (NMDA) receptor antagonists or opioid receptor agonists provide antinociception. Spinal coadministration of an NMDA receptor antagonist and morphine has an additive action for control of various pain states in animal models. The current study examined spinal coadministration of low doses of NMDA receptor antagonist, D-(-)-2-Amino-5-phosphonovalerate (D-APV), and mu-opioid receptor agonist, morphine sulfate (MS), in reducing visceral nociception using an acute bradykinin induced pancreatitis model in rats. METHODS: An intrathecal catheter was surgically inserted into the subarachnoid space for spinal drug administration in Sprague-Dawley rats. A laparotomy was performed for ligation and cannulation of the bile-pancreatic duct. Rats were pretreated intrathecally with artificial cerebrospinal fluid (aCSF), D-APV, MS, or combined administration of D-APV and MS. These treatments were given 30 min before noxious visceral stimulation with bradykinin injected through the bile-pancreatic catheter. Spontaneous behavioral activity tests, including cage crossing, rearing, and hind limb extension, were conducted before and after bradykinin injection into the bile-pancreatic duct to assess visceral nociception. RESULTS: Spinal pretreatment of D-APV or low doses of MS partially reduced visceral pain behaviors in this model. Pretreatments with combinations of low doses of MS (0.05-0.5 microg) and D-APV (1 microg) were maximally effective in returning all spontaneous behavioral activities to baseline. CONCLUSIONS: Spinal administration of combined doses of NMDA receptor antagonist, D-APV, and MS reversed three behavioral responses to induction of an acute pancreatitis model. These results suggest that in the clinical management of visceral pain, such as pancreatitis, restricted usage of glutamate antagonists might be useful as adjuvant potentiation at the onset of morphine therapy.  相似文献   
86.
OBJECTIVE: To examine, in a 2-year, non-comparative, open-label extension study, the safety, tolerability and efficacy of darifenacin controlled-release (CR) 7.5/15 mg once daily in patients with overactive bladder (OAB) who completed two 12-week randomized, double-blind, placebo-controlled 'feeder' studies. PATIENTS AND METHODS: Patients entering the extension received darifenacin 7.5 mg once daily for 2 weeks, after which a voluntary increase in dose to 15 mg was permitted. Thereafter, patients could adjust the dose (either 7.5 or 15 mg). Safety and tolerability were assessed from adverse events (AEs) and discontinuations. Efficacy was determined using various endpoints. RESULTS: In all, 716 patients entered the extension (mean age 57.3 years; 85.1% women) and 475 (66.3%) completed it (1089.9 patient-years of exposure). Darifenacin was well tolerated with no significant safety concerns. The most commonly reported AEs were dry mouth and constipation (all-causality rates 23.3% and 20.9%, respectively), leading to discontinuation in 1.3% and 2.4% of patients, respectively. Constipation infrequently required intervention, and analysis of bowel-habit questionnaires revealed that the reporting of constipation was related to minor changes in bowel habit rather than true constipation. The efficacy of darifenacin was maintained, including significant improvements in the number of incontinence episodes/week (median change -84.4% at 2 years, P < 0.001 vs feeder-study baseline). After 2 years, > 40% of patients achieved a > or = 90% reduction in incontinence episodes/week. CONCLUSION: In the first published 2-year, open-label study of a CR antimuscarinic agent, darifenacin 7.5/15 mg once daily had a favourable safety, tolerability and efficacy profile during the long-term treatment of OAB. As such, darifenacin represents a valuable therapeutic option for OAB.  相似文献   
87.
Signaling through the epidermal growth factor receptor (EGFR) by ligands such as epidermal growth factor (EGF), transforming growth factor α (TGFA), and amphiregulin (AREG) has been reported to have effects on skeletal growth. The role of betacellulin (BTC), another EGFR ligand, in skeletal development and bone metabolism is unknown. In previous experiments, transgenic mice overexpressing BTC ubiquitously under the control of the chicken β‐actin promoter (BTC‐tg) exhibited stunted growth and disproportionately sized long bones. In this study, we performed a detailed phenotypic analysis of BTC‐tg mice at 3, 6, and 9 wk of age. Osteoblastic cells from transgenic mice showed strong expression of BTC as determined by Western blots and by immunohistochemistry on bone sections. In femurs of male and female BTC‐tg mice, we found reduced longitudinal bone growth and a pronounced increase in total volumetric BMD. The increased femoral BMD was mainly caused by augmented endocortical bone apposition and subsequent cortical bone thickening. In contrast, vertebral BMD was reduced in BTC‐tg mice of both sexes. An overall similar phenotype was found in 6‐mo‐old BTC‐tg mice. The increase in cortical bone mass in the appendicular skeleton of BTC‐tg mice was largely blocked when they were crossed into the EgfrWa5 background characterized by a dominant negative EGFR. Our study showed that overexpression of BTC results in an EGFR‐dependent upregulation of cortical bone mass in the appendicular skeleton of mice, uncovering a potential novel anabolic pathway for cortical bone.  相似文献   
88.
To retrospectively compare low‐dose (7–10 mCi) to high‐dose (15–30 mCi) breast‐specific gamma imaging (BSGI) in the detection of breast cancer. A retrospective review of 223 consecutive women who underwent BSGI exam between February 2011 and August 2013 with subsequent pathologic analysis was performed. Women were divided into low‐dose and high‐dose groups. The results of BSGI and pathology were compared, and the sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were determined. A subgroup analysis was performed to evaluate specificity using benign follow‐up imaging to establish true‐negative results. There were 223 women who met inclusion criteria with 109 patients with 153 lesions in the low‐dose group and 114 patients with 145 lesions in the high‐dose group. Pathologic correlation demonstrates sensitivities of 97.6% (95% CI = 90.9–99.6%) and 94.6% (95% CI = 84.2–98.6%; p = 0.093), PPVs of 62.1% (95% CI = 53.2–70.3%) and 50.5% (95% CI = 40.6–60.3%, p = 0.089), and NPVs of 90.5% (95% CI = 68.2–98.3%) and 92.5% (95% CI = 78.5–98.0%, p = 0.781) in the low‐dose and high‐dose groups, respectively. Subgroup analysis included 72 patients with 98 lesions in the low‐dose group and 116 patients with 132 lesions in the high‐dose group, with a specificity of 53.7% (95% CI = 39.7–67.1%) and 66.3% (95% CI = 56.2–75.2%%, p = 0.143), respectively. Low‐dose BSGI demonstrated high sensitivity and NPV in the detection of breast cancer comparable to the current standard dose BSGI, with moderate specificity and PPV in a limited subgroup analysis, which was associated with a substantial number of false‐positives.  相似文献   
89.
DAA‐based regimens for chronic hepatitis C infection encourage treatment of “difficult‐to‐treat” cohorts. This study investigated efficacy and safety of DAA‐based regimens in HCV patients on dialysis or postkidney or liver/kidney transplantation. Twenty‐five patients treated with DAA combinations were evaluated: 10 were on dialysis (eight: hemodialysis, two: peritoneal dialysis), eight were kidney transplant recipients, and seven were liver/kidney transplant recipients. Except for one patient treated with daclatasvir ([DCV]/60 mg/QD)/simeprevir ([SMV]/150 mg/QD), the others received sofosbuvir‐based regimens ([SOF];400 mg/QD) combined with SMV:eight, DCV:13 or either ledipasvir ([LDV]90 mg/QD), ribavirin ([RBV];weight based) or pegylated interferon/RBV. HCV‐RNA was determined by Abbott RealTime (LLOQ]:12 IU/ml) or Roche AmpliPrep/COBAS TaqMan assay (LLOQ:15 IU/ml); treatment response evaluated every 4 weeks, at the end of treatment, and 4 and 12 weeks thereafter. Twenty‐four (96%) patients achieved SVR 12/24 (ITT‐analysis). Mean treatment duration was 15.1 ± 5.1 weeks (±SD), and two patients terminated prematurely – both reached SVR12. Six patients were hospitalized due to complications of underlying disease. One patient achieved SVR24 but was re‐infected (week 27). Kidney function remained stable; serum creatinine increased in only one patient – SOF was reduced to 400 mg/48 h. Treatment with DAA combinations in renally impaired HCV patients is highly effective and well tolerated. These findings call for further controlled trials and data from real‐life cohorts.  相似文献   
90.
After intramuscular implantation, BMP4-expressing NIH/3T3 fibroblasts and BMP4-expressing C2C12 myoblasts can promote ectopic cartilage and bone formation. Fibroblasts tend to undergo chondrogenesis, whereas myoblasts primarily undergo osteogenesis. These results suggest that endochondral bone formation may involve different cell types, a finding that could have major implications for the tissue engineering of bone and cartilage. INTRODUCTION: The delivery of BMP4 through cell-based gene therapy can trigger ectopic endochondral bone formation in skeletal muscle. We hypothesized that, when stimulated with or transduced to express BMP4, different types of cells residing within skeletal muscle might participate in different stages of endochondral bone formation. MATERIALS AND METHODS: We compared the responses of a fibroblast cell line (NIH/3T3), a myoblast cell line (C2C12), primary fibroblasts, and primary myoblasts to BMP4 stimulation in vitro. We then transduced the four cell populations to express BMP4 and compared their ability to promote ectopic endochondral bone formation in skeletal muscle. RESULTS: Under the influence of BMP4 in vitro and in vivo, NIH/3T3 cells differentiated toward both chondrogenic and osteogenic lineages, whereas most C2C12 cells underwent primarily osteogenic differentiation. NIH/3T3 cells genetically modified to express BMP4 induced delayed but more robust cartilage formation than did genetically modified C2C12 cells, which promoted rapid ossification. These differences in terms of the timing and amount of cartilage and bone formation persisted even after we introduced a retrovirus encoding dominant negative Runx2 (DNRunx2) into the C2C12 cells, which interferes with the function of Runx2. Superior osteogenic potential was also displayed by the primary myoblasts in vitro and in vivo compared with the primary fibroblasts. The different proliferation abilities and differentiation potentials exhibited by these cells when influenced by BMP4 may at least partially explain the differing roles that BMP4-expressing myogenic cells and BMP4-expressing fibroblastic cells play in endochondral bone formation. CONCLUSIONS: Our findings suggest that the process of endochondral bone formation in skeletal muscle after delivery of BMP4 involves different cell types, including fibroblastic cells, which are more involved in the chondrogenic phases, and myoblastic cells, which are primarily involved in osteogenesis. These findings could have important implications for the development of tissue engineering applications focused on bone and cartilage repair.  相似文献   
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