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1.
2.
N D Vaziri M Ismail D C Martin E Gonzales 《The International journal of artificial organs》1992,15(6):365-369
Renal transplant recipients treated with cyclosporine (CS) have been reported to be at increased risk of thrombotic complications. The present study was intended to examine the blood coagulation, fibrinolytic, and inhibitory systems in such patients. Eight transplant recipients on maintenance immunosuppression with CS and prednisone were studied. Five transplant recipients maintained on azathioprine (AZA) and prednisone and 32 normal volunteers served as controls. Plasma antigen concentrations and/or activities of various proteins in the above pathways were measured. Both the CS and AZA groups exhibited significant elevations of factor IX activity, von Willebrand factor (vWF), D-dimer, protein C and tissue type plasminogen activator (t-PA) levels when compared with the normal controls. In addition, CS group showed a significant elevation of alpha 2-macroglobulin activity and AZA group showed a significant reduction in factor XII activity when compared with the normal controls. Comparison of data from CS and AZA groups revealed higher factor XII activity and vWF concentration in the former group. In conclusion, transplant recipients treated with long-term cyclosporine and prednisone exhibited significant elevation of plasma vWF, D-dimer and protein C concentrations. In addition, both CS and AZA-treated transplant recipients showed increased plasma concentrations of D-dimer and t-PA. The latter observations suggest in vivo thrombin generation, fibrin formation and degradation. 相似文献
3.
BACKGROUND: Chronic renal failure (CRF) is associated with an atherogenic
lipid profile and an increased risk of ischaemic cardiovascular disease.
The associated hyperlipidaemia is reportedly ameliorated by erythropoietin
(Epo) therapy. According to a recent report, rats studied 3 weeks after 5/6
nephrectomy and fed a high- protein diet exhibited increased activities of
hepatic HMG-CoA reductase (HMG-CoAR) and cholesterol 7 alpha-hydroxylase
(Ch-7 alpha- H), despite normal corresponding mRNA values. DESIGN AND
METHODS: This study was designed to examine the effects of naturally
progressing CRF of longer duration as well as those of Epo therapy on gene
expressions of the key factors involved in hepatic cholesterol metabolism,
i.e., LDL receptor (LDLR), HMG-CoAR, and Ch-7 alpha-H. Sprague-Dawley rats
were randomized to the CRF group (5/6 nephrectomy), Epo-treated CRF group
(given Epo 150 U/kg/twice weekly) and sham-operated, placebo- treated
normal controls. They were allowed free access to regular rat chow and
studied 6 weeks after surgery. Liver mRNAs and protein mass or activities
of the above factors were studied. RESULTS: Plasma cholesterol
concentration was significantly increased in the CRF group (P < 0.001)
and was modestly lowered (P < 0.05) by Epo therapy. However, microsomal
cholesterol concentration and LDLR, HMG-CoAR, and Ch-7 alpha-H mRNA as well
as HMG-CoAR activity, and Ch-7 alpha-H and LDLR protein mass measurements
were virtually identical in the three groups. Thus, hepatic LDLR, HMG-CoAR,
and Ch-7 alpha-H mRNA and protein measurements in rats with CRF were
similar to those of the normal control group representing an inappropriate
response to the associated hypercholesterolemia. Epo therapy led to partial
amelioration of CRF- associated hypercholesterolaemia with no discernible
effect on hepatic tissue expression of the above factors.
相似文献
4.
5.
Autopsy data from 78 patients with end-stage renal disease (ESRD) treated with long-term hemodialysis were examined. Various pancreatic abnormalities were found in 47 (60%) patients. The most prevalent abnormality was pancreatitis which was seen in 22 patients (28%). Other lesions found with considerable frequency included fibrosis, hemosiderin deposits, calcification, cystic changes, amyloidosis and abscess formation. In addition hyalinization, atrophy or absence of islands of Langerhans and necrosis of peripancreatic fat were seen in several cases and inspissated secretions, focal ductular epithelial metaplasia and dilatation were noted in some patients. Comparison of the present data with those of a large survey of ESRD patients conducted prior to dialysis era indicates a considerable increase in the prevalence of pancreatic pathology in ESRD patients sustained by long-term hemodialysis treatment. 相似文献
6.
A necropsy study of the pathological findings in the digestive system of 19 renal transplant recipients revealed that gastrointestinal (GI), hepatobiliary, and pancreatic pathologies are common in renal transplant recipients. Fifteen of the 19 patients studied had GI pathology. Hepatobiliary pathology was the most common finding with all but one of the 19 cases exhibiting one or more abnormalities. Pancreatic abnormalities were less frequent with 11 patients demonstrating normal findings. 相似文献
7.
Marguerite Hatch Robert W. Freel N. D. Vaziri 《Pflügers Archiv : European journal of physiology》1993,423(3-4):206-212
In order to characterize oxalate handling by the P2 segment of the rabbit proximal colon, the fluxes of [14C]oxalate, 22Na+, and 36Cl– were measured in vitro using conventional short-circuiting techniques. In standard buffer the proximal colon exhibited net secretion of Na+ (–2.31±0.64 equiv cm–2 h–1), negligible net Cl– transport, and net secretion of oxalate (–12.7±1.6 pmol cm–2 h–1). Replacement of buffer Na+ or Cl– abolished net oxalate secretion, while HCO
3
–
-free media revealed a net absorption of oxalate (19.3±4.2 pmol cm–2 h–1) and stimulated NaCl absorption. Mucosal amiloride and dimethylamiloride (1 mM) significantly reduced the unidirectional fluxes of oxalate and enhanced sodium secretion by decreasing J
ms
Na
. The anion exchange inhibitor 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS; 0.1 mM, both sides) reduced the unidirectional fluxes of oxalate and chloride. Serosal epinephrine (50 M) stimulated oxalate absorption (21.3±6.3 pmol cm–2 h–1) and sodium absorption (5.71±1.20 equiv cm–2 h–1), whereas dibutyryl-cAMP enhanced oxalate secretion (–43.4±6.9 pmol cm–2 h–1) and stimulated chloride secretion (–7.27 ±0.64 equiv cm–2 h–1). These results indicate that the P2 segment of the proximal colon possesses (a) secretory as well as absorptive capacities, (b) oxalate fluxes that are mediated by pathways involving Na+, Cl–, HCO
3
–
transport and (c) a net oxalate flux that is sensitive to absorptive and secretory stimuli. 相似文献
8.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph. 相似文献
9.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
10.