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Therapeutic drug monitoring (TDM) of Neoral has been studied widely and C2 monitoring has been shown to be superior to C0 monitoring in predicting outcomes. However, data are scarce in diabetic renal transplant recipients who may have gastroparesis. We studied 0 to 8 hour pharmacokinetic profiles (AUC(0-8h)) of Neoral on 3 consecutive days in 18 diabetic adults who had stable renal function for at least 6 months after transplantation and no overt symptoms of diabetic gastroparesis. All patients had diabetes mellitus (DM) for at least 5 years. Intrapatient variability of C2 levels was 28% (range, 6%-68%); it was < or =20% in 9 patients (50%) and >60% in 2 patients. Correlation coefficients between AUC(0-8h) and AUC(0-4h), between C2 and AUC(0-8h), and between C0 and AUC(0-8h) were 0.95, 0.86, and 0.77, respectively. Exposure phase (85% of AUC(0-8h)) was longer than 4 hours in all completed (48/54; 89%) profiles; it was longer than 6 hours in 20 profiles. C4 levels had good correlation with AUC(0-8h) (0.86) and low intrapatient variability (16% +/- 11%; range, 2%-39%). Thirteen of 18 patients (72%) had intrapatient variability of C4 < or = 20%. We conclude that the exposure phase of Neoral is prolonged more than 4 hours in adult renal transplant recipients with long-term diabetes, even in the absence of symptoms of gastroparesis. Because of very high intrapatient variability in this group of patients, C2 levels may not be reliable for TDM of Neoral despite high correlation with AUC(0-8h). C4 level may be a valid alternative for these patients.  相似文献   
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OBJECTIVE: The insertion of absent or underexpressed genes into cancer cells to alter their malignant phenotype is an important potential application of available gene therapy technology. One of the more common viral vector systems that has been extensively studied for this purpose are the replication-deficient adenoviruses (Ad). Adenoviral infection of cells is mediated through a complex pathway, initiated following viral-cell attachment. Adenoviral-cell attachment occurs following interactions with a 46-kDa transmembrane protein with high affinity for both the Coxsackie and adenovirus, designated the CAR (Coxsackie and adenoviral receptor). Additional important cell-viral interactions that occur involve the alpha(v)-based integrins, specifically alpha(v)beta3 and alpha(v)beta5. The purpose of the present study was to determine the extent of expression and localization of the known Ad receptor proteins (CAR, alpha(v)beta3, and alpha(v)beta5) in normal and cancerous human bladders. MATERIAL AND METHODS: Frozen tissue samples of normal bladder and invasive transitional cell cancers of the bladder were evaluated. Tissue blocks containing muscle-invasive transitional cell carcinoma (TCC) were obtained following radical cystectomy, which were performed at our institution. Thirty-two invasive transitional cell bladder tumors were evaluated, each with a matched sample of histologically normal-appearing bladder used as a control. Four additional samples of normal bladder were obtained from patients with no evidence of disease of the bladder and served as further controls. Three additional cases of invasive bladder cancer with no matching normal tissue were also evaluated. Identification of the CAR receptor was performed using the anti-CAR mouse monoclonal antibody designated RmBC. The integrins alpha(v)beta3 and alpha(v)beta5 were identified using the mouse monoclonal antibodies designated LM609 and P1F6 respectively. All slides were evaluated by two of the authors (M.B., B.B.) without knowledge of the clinical and pathological data. RESULTS: Normal bladder: Normal bladder mucosa demonstrated a marked positivity for CAR in 29/35 (82.8%) cases. In contrast, normal transitional epithelial cells were uniformly negative when tested for the integrins alpha(v)beta3 and alpha(v)beta5. Subepithelial tissues, specifically the connective tissue components of the lamina propria and deep muscle wall of the bladder, were positive for alpha(v)beta3 and for alpha(v)beta5 in 61 and 75% of samples, respectively. Endothelial cells associated with the various layers throughout the bladder uniformly expressed both integrins and served as a consistent internal control for both antibodies. An almost identical staining pattern of the endothelium was observed using LM609 and P1F6 in all samples tested. Bladder transitional cell carcinoma: CAR immunoreactivity against TCC cells was uniformly decreased compared to normal transitional cells. Nine tumors exhibited a weak positivity for CAR while the remaining samples were negative. In some cases, the absence of CAR positivity was associated with histological evidence of carcinoma in situ. In 6 cases, it led to the identification of small regions of carcinoma in situ that were not noted on primary pathological evaluation. Peritumoral connective tissue expressed both integrins in the majority of cases, similar to the pattern described above for normal bladder. Transitional cell cancers demonstrated a similar pattern of expression of alpha(v)beta5, in which all tumor cells exhibited minimal or no staining. CONCLUSIONS: The success of all viral-mediated gene therapy strategies relies on the ability of the vector to efficiently deliver its genetic material to a target cell population. In the current study, we demonstrate that the bladder epithelial layer consistently expresses high levels of CAR. Deeper layers of the epithelium also express CAR, including the basal layer cells. A decrease in the expression of CAR appears as an early event in bladder carcinogenesis. We observed that both alpha(v)beta3 and alpha(v)beta5 are strongly expressed in muscle cells surrounding the neoplastic cells, as well as within the peritumoral connective tissue. In cases of invasive bladder cancer that have lost CAR expression, an adenoviral vector may still be utilized through the less efficient interactions with the integrins. Bladder tumor tissue may be less susceptible to an adenoviral-mediated gene therapy approach in which a significant percentage of tumor cells require transduction. Adenoviral uptake by tumor or peritumoral cells with subsequent gene transfer could be predicted by the level of CAR and alpha(v)-based integrin expression. This would enhance our ability to identify those patients whose tumors would be more susceptible to Ad-mediated gene delivery as part of an antitumor treatment.  相似文献   
134.
Chronic contained rupture of an abdominal aortic aneurysm (AAA) is a rare event, making its diagnosis difficult. A delayed diagnosis and delayed surgical repair compromise the outcome. In this paper the authors report the case of a chronic contained rupture of an AAA causing spinal destruction, in which diagnosis was difficult because the lesion produced symptoms mimicking those of pyogenic spondylitis.  相似文献   
135.
The aim of this study was to determine genotypes and clinical aspects associated with bone mineral density (BMD) in postmenopausal women from Córdoba, Argentina. Polymorphisms were assessed by RFLP-PCR technique using BsmI and FokI for vitamin D receptor gene (VDR) and XbaI and PvuII for estrogen receptor-alpha gene (ERalpha) as restrictases. Sixty-eight healthy, 54 osteopenic, and 64 osteoporotic postmenopausal women were recruited. Femoral neck and lumbar spine BMD were inversely correlated with age in the entire analyzed population. Height was lower in osteopenic and osteoporotic women as compared to healthy women (P < 0.05). Weight and body mass index (BMI) were the lowest in osteoporotic women (P < 0.01 versus healthy group). Serum procollagen type I Nterminal propeptide (PINP) was higher in osteoporotic women as compared to the other groups. Distribution of VDR and ERalpha genotypes was similar in the three groups. Genotype bb (VDR) was associated with low values of lumbar BMD in the healthy group (P < 0.05 versus genotype Bb), and with low values of femoral BMD (P < 0.05 versus genotype BB) in osteoporotic women. BB*Pp interaction was associated with the highest femoral neck BMD (P < 0.05), whereas the bb*xx interaction was associated with the lowest femoral neck BMD in the total population analyzed (P < 0.05). In conclusion, parameters such as age, height, weight, BMI, serum PINP, VDR genotypes, and interactions between VDR and ERalpha genotypes could be useful to predict a decrease in BMD in Argentine postmenopausal women.  相似文献   
136.
Gene therapies to produce insulin in diabetic patients have been considered for several years. Genetic engineering of ectopic insulin production and secretion in autologous non-beta-cells has been tested in different tissues. Recently, gut K-cells have been shown to express glucokinase, the glucose sensor of pancreatic beta-cells. K-cells are responsible for the secretion of the glucose-dependent insulinotropic peptide (GIP). Transfection of K-cells by a specific plasmid to produce insulin correlated to glucose level is being considered. Cationic liposomes are non-viral gene delivery to lung, spleen, liver and intestinal cells. DOTAP-GIP/Ins plasmid complex was used for transfection of K-cells in vivo. RT-PCR assay of human insulin mRNA revealed that the transfection of insulin gene by DOTAP liposome is an efficient tool. The genetic engineering of ectopic insulin production and secretion in autologous non-beta-cells is an appropriate method. The potential of the transmission of a constructed plasmid, which contains human insulin gene under the control of GIP promoter, to gut K-cells could be considered for treatment of diabetes.  相似文献   
137.
OBJECTIVES: Although children with very low birth weight (VLBW, <1500 g) are at high risk for developmental impairments, we know little about the long-term effects of VLBW on families. This study examined long-term family outcomes and their stability over time. METHODS: Participants were the families of 64 children with <750 g birth weight, 54 with 750-1499 g birth weight, and 66 term-born controls. Family burden and parental distress were assessed annually as part of longitudinal follow-up of the children from mean ages 11-14 years. RESULTS: Family burden and parental distress were higher in the <750 g group than in the term-born group, but differences varied with the child's age and family environment. CONCLUSIONS: The findings document long-term effects of VLBW on families that are moderated by the degree of low birth weight, child's age, and family environment.  相似文献   
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Background Esophageal injury is a rare, but catastrophic complication of radiofrequency (RF) pulmonary vein isolation. It is not known if cryoablation is less likely to injure esophageal tissue. The purpose of this study is to compare the effects of RF and cryoablation on the structural integrity of esophageal tissue. Methods and results Porcine esophageal tissue was sectioned into 396 strips measuring 3 mm in width by 30 mm in length. Samples were randomly assigned to receive no ablation (149 specimens in the control group), RF ablation (126 specimens) or cryoablation (121 specimens). A single ablation was administered in the center of the tissue sample. A force gauge was used to measure the tensile strength of the tissue sample in Newtons. Groups were compared using ANOVA and a Bonferroni post-test. The mean tensile strength in the control group was 2.19 N (SD, 2.17), 1.66 N (SD, 0.88) for RF ablated tissue and 1.96 N (SD, 1.68) for cryo. RF ablation resulted in a significant reduction in esophageal tensile strength when compared to control (t = 2.59), however cryo did not (t = 1.11). On microscopic evaluation RF ablation disrupted elastic fiber architecture whereas cryoablation did not. Conclusions Cryoablation has no significant adverse impact on the structural integrity of esophageal tissue. Cryoablation may be a safer alternative to RF for left atrial ablation and reduce the risk of esophageal injury and atrial-esophageal fistula formation.  相似文献   
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