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21.

Background and objectives

In ANCA-associated GN, severe renal dysfunction portends a poor prognosis for renal recovery and patient survival. This study evaluated the prognostic factors affecting renal and patient outcomes in patients presenting with severe kidney failure to guide immunosuppressive therapy.

Design, setting, participants, & measurements

This study retrospectively evaluated clinical and histopathologic characteristics of 155 patients who underwent biopsy between October 1985 and February 2011 (median eGFR at presentation, 7.1 ml/min per 1.73 m2; 87% required hemodialysis), all treated with immunosuppressive medications. Three outcomes of interest were measured: patient survival, renal survival, and treatment response (defined as dialysis-free survival without active vasculitis by 4 months after biopsy). Competing risk, Cox, and logistic regression analyses were conducted for each outcome measure.

Results

Within 4 months after biopsy, treatment response was attained in 51% of patients, 35% remained on dialysis, and 14% died. In a competing risk analysis, estimated cumulative incidence rates of ESRD and disease-related mortality were 26% and 17% at 1 year and 32% and 28% at 5 years, respectively. Cyclophosphamide therapy and treatment response by 4 months were independently associated with patient and renal survival, adjusting for the percentage of normal glomeruli, histopathologic chronicity index score, and baseline clinical characteristics. Only 5% of patients still dialysis dependent at 4 months subsequently recovered renal function. Low chronicity index score (odds ratio [OR], 1.16; 95% confidence interval [95% CI], 1.04 to 1.30, per unit decrease) and baseline eGFR>10 ml/min per 1.73 m2 (OR, 2.77; 95% CI, 1.09 to 7.01) were significantly associated with treatment response by 4 months. Among cyclophosphamide-treated patients, the likelihood of treatment response was >14% even with highest chronicity index score and eGFR<10 ml/min per 1.73 m2.

Conclusions

Although low baseline renal function and severe renal scarring are associated with lower treatment response rate, no “futility” threshold could be identified. Conversely, continued immunosuppressive therapy beyond 4 months is unlikely to benefit patients who remain dialysis dependent.  相似文献   
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目的探讨血小板源性生长因子D(PDGF-D)与髓过氧化物酶(MPO)在大肠癌组织和大肠腺瘤组织中的表达及其临床意义。方法通过免疫组织化学染色法检测大肠癌组织及大肠腺瘤组织中PDGF-D与MPO的表达及其相关性。采用免疫组化染色方法检测88例大肠癌石蜡包埋组织、72例大肠腺瘤组织中PDGF-D与MPO的表达,并分析MPO和PDGF-D的表达与大肠癌临床病理特征的关系。结果大肠癌组织中PDGF-D与MPO阳性表达率分别为85.23%、63.64%,均显著高于大肠腺瘤组织(34.72%、27.78%),差异有统计学意义(P0.01)。PDGF-D与MPO在大肠癌组织中的表达呈正相关(r=0.29,P0.05)。结论 PDGF-D与MPO可能参与了大肠癌的启动及发生过程,在大肠癌的发生、发展和转移过程中起着重要作用。  相似文献   
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Inflammation is involved in the pathophysiology of Alzheimer’s disease (AD), with multiple inflammatory processes implicated in its risk and progression. This review included original peer-reviewed studies measuring the cerebrospinal fluid or peripheral blood concentrations of protein markers specifically related to neutrophil activity in healthy controls (HC) and in patients with AD or mild cognitive impairment (MCI). A total of 35 studies (NHC = 3095, NAD = 2596, NMCI = 1203) were included. Random-effects meta-analyses were used to estimate between-groups standardized mean differences (SMD) and 95 % confidence intervals. In blood, concentrations of myeloperoxidase (MPO; NAD/NHC = 271/209, SMD = 0.41 [0.20, 0.62]; I2 = 15.7 %) and neutrophil gelatinase associated lipocalin (NGAL; NAD/NHC = 273/185, SMD = 0.30 [0.11, 0.49]; I2 < 0.005 %) were significantly higher in AD relative to HC. Peripheral blood concentrations of NGAL were also higher in MCI compared to HC (NMCI/NHC = 489/145, SMD = 0.39 [0.11, 0.67]; I2 = 38.6 %). None of the protein markers exhibited a significant difference between HC, MCI, or AD groups in the cerebrospinal fluid. The evidence suggests that peripheral neutrophil activation, as indicated by blood concentrations of NGAL and MPO, may be a pathological feature of cognitive impairment due to AD, evident at stages of MCI and AD dementia.  相似文献   
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Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10–4.59 and P = 0.032 OR 2.32 CI 1.07–5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.  相似文献   
27.

Aim of the study

Water extract of Geijigajakyak-Tang (GJT) consisting of five crude drugs [dried root of P. lactiflora Peony (Paeoniaceae), dried trunk bark of C. cassia Blume (Lauraceae), seed of Z. jujube var. inermis Mill (Rhamnaceae), fresh root of Z. officinale Rocoe (Zingiberaceae) and dried trunk bark of G. uralensis Fish (Leguminosae)] is a folk medicine used for the treatment of chronic colitis. This study was designed to further elucidate the effect of GJT on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.

Materials and methods

GJT orally given to mice before and after TNBS intoxication, and their clinical and morphological changes, myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels in colon tissues, were evaluated on Day 8 post-TNBS. Furthermore, the effect of six major constituents of individual herbs on ileum smooth muscle contraction and neutrophil chemotaxis was studied.

Results

GJT had a significant anti-inflammatory effect based on clinical and morphologic changes, MPO activity and MDA levels in colon tissues as compared with sham control. GJT and 5 major active constituents of individual herbs, paeoniflorin, cinnamaldehyde, jujuboside A, jujubogenin, and diammonium glycyrhhizinate significantly inhibited neutrophil chemotaxis. GJT significantly inhibited muscle contraction (IC50; 2.10 ± 0.11 mg/ml), and 1,8-cineol has the most spasmolytic activity (IC50; 0.10 ± 0.03 mg/ml).

Conclusion

GJT has significant anti-inflammatory effects on TNBS-induced colitis via inhibitions of smooth muscle contraction and neutrophil chemotaxis.  相似文献   
28.
ObjectiveTo investigate the clinical features, pathological renal findings, and outcomes in young adults with anti-neutrophil cytoplasmic antibody (ANCA) seropositivity.MethodsAdults aged ≤35 years, with ANCA seropositivity, who underwent renal biopsy and received treatment comprising a combination of corticosteroids and cyclophosphamide between January 2004 and May 2018, were retrospectively enrolled.ResultsThirteen patients with ANCA seropositivity were included, all of whom presented with kidney disease at diagnosis: 10 (76.9%) with ANCA-associated pauci-immune glomerulonephritis, one with ANCA-associated crescentic glomerulonephritis with immune complex deposition, one with immunoglobulin A nephropathy, and one with membranous nephropathy. The median serum creatinine level was 183.2 μmol/l (range, 55.0–1024.0 μmol/l). Respiratory symptoms (9/13 [69.2%]) and nonspecific gastrointestinal symptoms (5/13 [38.5%]) were the most common extrarenal manifestations. Remission was achieved in 10 (91%) of 11 ANCA-associated nephritis cases, and median interval from diagnosis to relapse was 30 months (range, 9–63 months). Cumulative relapse-free survival rates at 1 and 5 years were 100% and 88.9%, respectively. Overall, 1-year and 5-year renal survival rates were 80.8% and 58.9%, respectively.ConclusionRenal histopathology varied in young adults with ANCA seropositivity. Although relapse rates in this young adult population were generally low, long-term renal survival rates remain unsatisfactory.  相似文献   
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BACKGROUND & AIMS: We tested whether the attenuation of experimental colitis by live probiotic bacteria is due to their immunostimulatory DNA, whether toll-like receptor (TLR) signaling is required, and whether nonviable probiotics are effective. METHODS: Methylated and unmethylated genomic DNA isolated from probiotics (VSL-3), DNAse-treated probiotics and Escherichia coli (DH5 alpha) genomic DNA were administered intragastrically (i.g.) or subcutaneously (s.c.) to mice prior to the induction of colitis. Viable or gamma-irradiated probiotics were administered i.g. to wild-type mice and mice deficient in different TLR or in the adaptor protein MyD88, 10 days prior to administration of dextran sodium sulfate (DSS) to their drinking water and for 7 days thereafter. RESULTS: Intragastric and s.c. administration of probiotic and E. coli DNA ameliorated the severity of DSS-induced colitis, whereas methylated probiotic DNA, calf thymus DNA, and DNase-treated probiotics had no effect. The colitis severity was attenuated to the same extent by i.g. delivery of nonviable gamma-irradiated or viable probiotics. Mice deficient in MyD88 did not respond to gamma-irradiated probiotics. The severity of DSS-induced colitis in TLR2 and TLR4 deficient mice was significantly decreased by i.g. administration of gamma-irradiated probiotics, whereas, in TLR9-deficient mice, gamma-irradiated probiotics had no effect. CONCLUSIONS: The protective effects of probiotics are mediated by their own DNA rather than by their metabolites or ability to colonize the colon. TLR9 signaling is essential in mediating the anti-inflammatory effect of probiotics, and live microorganisms are not required to attenuate experimental colitis because nonviable probiotics are equally effective.  相似文献   
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