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81.
Excess risk of renal allograft loss associated with cigarette smoking.   总被引:6,自引:0,他引:6  
BACKGROUND: Cigarette smoking contributes to a number of health-related problems, but its impact on renal transplant survival beyond accelerated patient death is unclear. METHODS: We performed a cohort study of 645 adult renal allograft recipients from 1985 to 1995 to evaluate the relationship between smoking and graft outcome. RESULTS: Twenty-four percent of recipients (156/645) were smokers at the time of transplant evaluation. Of these, 90% continued to smoke after transplantation. Pretransplant smoking was significantly associated with reduced overall graft and death-censored graft survival. Patients who were smokers at the time of pretransplant evaluation had kidney graft survival of 84%, 65%, and 48% at 1, 5, and 10 years, respectively, compared with graft survival in nonsmokers of 88%, 78%, and 62% (P=0.007). Pretransplant smoking adversely affected death-censored graft survival in recipients of cadaveric (P=0.02) and of living donor kidneys (P=0.02). Reduced graft survival in pretransplant smokers could not be accounted for by differences in rejection (64% vs. 61%, P=0.35). In a multivariate analysis, pretransplant smoking was associated with a relative risk of 2.3 for graft loss. Among patients with a smoking history before transplantation, death-censored graft survival was significantly higher for those who quit smoking before transplant evaluation. CONCLUSIONS: Cigarette smoking before kidney transplantation contributes significantly to allograft loss. The effect of smoking on graft outcome is not explained by increases in rejection or patient death. Smoking cessation before renal transplantation has beneficial effects on graft survival. These effects should be emphasized to patients with end-stage renal disease who are considering renal transplantation.  相似文献   
82.
Acute interstitial nephritis (AIN) is a known cause of acute renal failure in children. In most instances, drug therapy is the offending agent. Although granuloma formation has been observed in drug-induced interstitial nephritis, it is not a commonly associated manifestation. This is a case of a 15-year-old white female with Tetralogy of Fallot and pulmonary atresia who developed acute renal failure secondary to drug-induced interstitial nephritis and renal granulomas. In addition to interstitial edema with eosinophils and lymphocytes, her renal biopsy showed interstitial granulomas, immune complexes within tubular basement membranes, and the unusual feature of multinucleated giant cells engulfing tubules. Her acute renal failure resolved after the withdrawal of antibiotics and the initiation of intravenous steroid therapy.  相似文献   
83.

Objective

Restoration of acetabular anatomy and biomechanics at revision hip surgery by replacing deficient acetabular bone through impaction of allograft and/or autograft bone chips.

Indications

Aseptic loosening of the socket due to osteolysis, bone loss from infection, iatrogenic bone loss due to implant removal, and in the primary setting protrusio acetabuli, dysplasia and previous acetabular fracture.

Contraindications

Large segmental peripheral acetabular defects which cannot be contained, the presence of untreated infection, unstable acetabular fractures, previous radiotherapy to the affected hip area.

Surgical technique

Sound exposure of the acetabulum with delineation of the bony defect. Creation of a host environment suitable for bone graft and containment of segmental defects using rim mesh or porous augments. Impaction grafting using layered allograft or autograft bone chips of 0.8–1 cm3, packed using hemispherical impactors, followed by cementing of a polyethylene acetabular component with pressurisation.

Postoperative management

Partial weight bearing 6 weeks, modified depending on level of containment and intra-operative findings.

Results

A successful and reproducible technique with survival up to 87?% at 20 years for aseptic loosening in the revision setting.  相似文献   
84.
Recurrence of hepatitis C (HCV) postliver transplant is universal, with a subgroup developing rapid hepatic fibrosis. Toll‐like receptors (TLRs) are critical to innate antiviral responses and HCV alters TLR function to evade immune clearance. Whether TLRs play a role in rapid HCV recurrence posttransplant is unknown. We stimulated peripheral blood mononuclear cells (PBMCs) from 70 patients with HCV postliver transplant with TLR subclass‐specific ligands and measured cytokine production, TLR expression and NK cell function. Rate of fibrosis progression was calculated using posttransplant liver biopsies graded by Metavir scoring (F0–4; R = fibrosis stage/year posttransplant; rapid fibrosis defined as >0.4 units/year). Thirty of 70 (43%) patients had rapid fibrosis progression. PBMCs from HCV rapid‐fibrosers produced less IFNα with TLR7/8 stimulation (p = 0.039), less IL‐6 at baseline (p = 0.027) and with TLR3 stimulation (p = 0.008) and had lower TLR3‐mediated monocyte IL‐6 production (p = 0.028) compared with HCV slow fibrosers. TLR7/8‐mediated NKCD56 dim cell secretion of IFNγ was impaired in HCV rapid fibrosis (p = 0.006) independently of IFNα secretion and TLR7/8 expression, while cytotoxicity remained preserved. Impaired TLR3 and TLR7/8‐mediated cytokine responses may contribute to aggressive HCV recurrence postliver transplantation through impaired immune control of HCV and subsequent activation of fibrogenesis.  相似文献   
85.
This study examined bereaved children's HPA‐axis functioning (cortisol awakening response; CAR) in relation to psychological distress, coping, and surviving parents' grief reactions. Participants included 38 children (20 girls) with recent parental loss (previous 6 months) and 28 of their surviving caregivers (23 women) who were assessed using self‐report instruments and in‐person, semistructured interviews. Interviews involved discussions about the child's thoughts and feelings related to the loss. Participants provided 3 saliva samples at home (awakening, 30 minutes later, and evening) over 3 successive days, beginning on the day following the interview. Results show a significant relation between dampening of the child's Day 1 CAR and more symptoms of anxiety (r = ?.45), depression (r = ?.40), posttraumatic stress (r = ?.45), and maladaptive grief (r = ?.43), as well as higher levels of avoidant coping (r = ?.53). Higher levels of parental maladaptive grief were also associated (r = ?.47) with a dampening of the child's Day 1 CAR. Our results raise the possibility that blunted CAR may be a result of accumulating allostatic load and/or a result of emotionally challenging events (discussions regarding the deceased) and their subsequent processing (or lack thereof) within the family, which may be particularly stressful for those bereaved children experiencing high levels of psychological distress, avoidant coping, and parental maladaptive grief.  相似文献   
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To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.  相似文献   
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