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71.
72.
Cyclosporine Interacts with Mycophenolic Acid by Inhibiting the Multidrug Resistance-Associated Protein 2 总被引:5,自引:0,他引:5
Dennis A. Hesselink Reinier M. van Hest Ron A. A. Mathot Fred Bonthuis Willem Weimar Ron W. F. de Bruin Teun van Gelder 《American journal of transplantation》2005,5(5):987-994
In mycophenolate mofetil (MMF)-treated organ transplant recipients, lower mycophenolic acid (MPA) plasma concentrations have been found in cyclosporine (CsA) compared with tacrolimus (Tac)-based immunosuppressive regimens. We previously demonstrated that CsA decreases exposure to MPA and increases exposure to its metabolite MPA-glucuronide (MPAG), possibly by interfering with the biliary excretion of MPAG. To elucidate the role of the multidrug resistance-associated protein (Mrp)-2 in the interaction between MMF and CsA, we treated three groups of 10 Mrp2-deficient rats (TR- rat) for 6 days with either vehicle, CsA (8 mg/kg) or Tac (4 mg/kg) by oral gavage. Hereafter, co-administration with MMF (20 mg/kg) was started in all groups and continued through day 14. The 24-h MPA/MPAG area under the concentration-time curve (AUC) was determined after single (day 7) and multiple MMF doses (day 14). On both study days, there were no significant differences in the mean MPA and MPAG AUC between CsA and Tac-treated animals. We conclude that the pharmacokinetics of MMF are comparable in Mrp2-deficient rats receiving either CsA or Tac as co-medication. This finding suggests that CsA-mediated inhibition of the biliary excretion of MPAG by the Mrp2 transporter is the mechanism responsible for the interaction between CsA and MMF. 相似文献
73.
74.
Belinda Garner Andrew M. Chanen Lisa Phillips Dennis Velakoulis Stephen J. Wood Henry J. Jackson Christos Pantelis Patrick D. McGorry 《Psychiatry Research: Neuroimaging》2007,156(3):257-261
This study used magnetic resonance imaging to examine pituitary gland volume (PGV) in teenage patients with a first presentation of borderline personality disorder (BPD). No difference in PGV was observed between healthy controls (n = 20) and the total BPD cohort (n = 20). However, within the BPD cohort, those exposed to childhood trauma (n = 9) tended to have smaller pituitaries (− 18%) than those with no history of childhood trauma (n = 10). These preliminary findings suggest that exposure to childhood trauma, rather than BPD, per se, might be associated with reduced PGV, possibly reflecting hypothalamic–pituitary–adrenal axis dysfunction. 相似文献
75.
J. M. Wardlaw M. S. Dennis R. I. Lindley R. J. Sellar C. P. Wadaw 《Journal of neurology》1996,243(3):274-279
The aim of the study reported here was to test the validity of a simple clinical classification of acute ischaemic stroke (Oxfordshire Community Stroke Project, OCSP) in predicting the site and size of cerebral infarction on computed tomography (CT). Consecutive patients admitted to hospital with acute ischaemic stroke were prospectively identified and classified into one of four clinical syndromes according to the OCSP classification, blind to the result of CT. The CT brain scans were classified blind to the clinical features into those demonstrating: small, medium or large cortical infarcts; small or large subcortical infarcts in the anterior circulation territory; and posterior cerebral circulation territory infarcts. A total of 108 patients were included. A recent infarct was seen. on the CT scan in 91 patients (84%), and the clinical classification correctly predicted the site and size of the cerebral infarct in 80 of these (88%; 95% confidence interval 77–92%). The positive predictive value was best for large cortical infarcts (0.94) and worst for small subcortical infarcts (0.63). The OCSP clinical classification is a reasonably valid way of predicting the site and size of cerebral infarction on CT and can, therefore, be used very early after stroke onset before the infarct appears on the scan. 相似文献
76.
Energy requirements for cancer patients and the effect of total parenteral nutrition 总被引:1,自引:0,他引:1
H W Merrick C L Long G P Grecos R S Dennis W S Blakemore 《JPEN. Journal of parenteral and enteral nutrition》1988,12(1):8-14
Limited data are available concerning resting metabolic expenditure (RME) in cancer patients and the effect of RME by varying glucose intake. This study describes the measurements on 21 patients with colorectal cancer while fasting and with incremental levels of standard TPN-glucose system by central vein. Following an overnight fast, the measured mean +/- SEM percent difference from the predicted RME for the male group was 4.13 +/- 1.67% and the female group, 2.09 +/- 2.09%. The overall mean percent difference of 2.95 +/- 1.45 suggests that colorectal cancer does not cause an increase in energy expenditure. Hepatic metastases in 11 of the patients did not influence RME. The data from the 21 patients indicate a statistically significant increase in RME with TPN compared to postabsorptive states in females of 37%, in males 21.88%, and combined of 29.88%. Progressively greater increases in RME were seen when calories provided incrementally exceeded the basal RME. Carbohydrate loading in excess of the patient's calorie need, as indicated by the respiratory quotient (RQ) greater than 1.0, results in fat synthesis and other energy-costing processes. The basal RME demonstrates that these cancer patients are not hypercatabolic, but do respond to high-level force-feeding with markedly increased metabolic expenditures. 相似文献
77.
Bauer Thomas R. Jr; Schwartz Barbara R.; Conrad Liles W.; Ochs Hans D.; Hickstein Dennis D. 《Blood》1998,91(5):1520-1526
78.
79.
Spiros Manolidis C. Gary Jackson Peter G. Von Doersten Dennis Pappas Michael E. Glasscock III 《Skull base》1997,7(3):129-137
Lateral skull base surgery has remained the surgical frontier of new developments in the treatment of lesions heretofore difficult to access. Examination of surgical results stimulates technical innovation and provides an intervention risk-benefit ratio assessment for particular lesions useful in management planning. With this in mind, we report the updated collective experience with lateral skull base surgery at the Otology Group over the past 20 years. Two hundred ninety-eight patients underwent surgical intervention for lateral skull base lesions. In 81 patients these lesions were malignant; in 217, benign. Of the benign lesions, 165 were glomus tumors: 139 glomus jugulare, 19 glomus vagale, and 7 glomus tympanicum. The remainder comprised 21 menigniomas, 14 neuromas, two neurofibromas, and a small group of much rarer entities. The philosophy of surgical approach, results, and follow-up are discussed. 相似文献
80.
A Teratogenic Deformity Index for Evaluating Impacts of Selenium on Fish Populations 总被引:1,自引:0,他引:1
A.Dennis Lemly 《Ecotoxicology and environmental safety》1997,37(3):259-266
This paper describes a method for using teratogenic deformities in fish as the basis for evaluating impacts of selenium contamination. Teratogenic deformities are reliable bioindicators of selenium toxicosis in fish. They are produced in response to dietary exposure of parent fish and subsequent deposition of selenium in eggs. There is a close parallel between selenium concentrations in eggs, incidence of teratogenic deformities in larvae, and magnitude of reproductive failure. Using these relationships, an index was developed for teratogenic-based assessment of impacts to fish populations. The index is composed of three ratings that signify increasing levels of terata-induced population mortality: 1, negligible impact (<5% population mortality); 2, slight to moderate impact (5–20% population mortality); 3, major impact (>20% population mortality). Each rating is based on the anticipated population-level impact of the corresponding degree of mortality. Teratogenic-based impact assessment provides a conclusive cause–effect linkage between the contaminant and the fish. It is particularly useful for verifying selenium-induced impacts on reproductive success because poor reproduction can be caused by many things—i.e., fluctuating water levels, nest predation, food shortages, poor recruitment, etc. The index given here should be a useful tool for evaluating the effect of selenium on fish populations. Moreover, application of this technique may save considerable time and money by identifying the most efficient use of manpower and funds early in the assessment process. 相似文献