Clinical, Pathological, and Prognostic Characteristics of Glomerulonephritis Related to Staphylococcal Infection.

Staphylococcal infection has become a common cause of postinfectious glomerulonephritis in the past 3 decades. Because few investigations focus on this disease, the demographics and clinicopathological features of glomerulonephritis related to staphylococcal infection are not well characterized. We conducted a pooled analysis of published literature in electronic databases and analyzed the clinical features, laboratory findings, and histopathological changes. The patients were divided into 4 groups based on their prognosis: remission, persistent renal dysfunction, end-stage renal disease (ESRD), or death. A logistic regression model was used to identify the determinants of disease outcome. A total of 83 (64 men) patients with glomerulonephritis related to staphylococcal infection from 31 reports were analyzed. The mean age was 58 years (58 ±â€Š17). Majority of the reports originated from Taiwan, Japan, and the United States. Clinical characteristics of the cases were hematuria (82/83), proteinuria (78/83), and acute kidney injury (75/83). Visceral abscesses (26/83) and skin infections (24/83) were the common sites of infection. Methicillin-resistant Staphylococcus aureus was the most common pathogen. The dominant or codominant deposition of IgA or C3 along the glomeruli was an important feature identified by immunofluorescence. There were 19 patients (22.9%) that progressed to dialysis-dependent ESRD. Twelve patients (14.5%) died. A univariate regression analysis indicated that diabetes mellitus (DM) (odds ratio [OR] 2.96; 95% confidence interval [CI] 1.03-8.48; P = 0.04) and age (OR 4.80; 95% CI 1.84-12.53; P = 0.001) were risk factors for ESRD or death. A multivariate regression analysis also revealed that age (OR 4.90; 95% CI 1.82-13.18; P = 0.002) and DM (OR 3.07; 95% CI 0.98-9.59; P = 0.05) were independent risk factors for unfavorable prognosis. Glomerulonephritis related to staphylococcal infection has different features than typical postinfectious glomerulonephritis. The diagnosis of glomerulonephritis related to staphylococcal infection relies on immunofluorescence and electron microscopy findings. Age and DM are independent risk factors of poor prognosis for glomerulonephritis related to staphylococcal infection.

Effect of c-erbB2 overexpression on prognosis in osteosarcoma: evidence from eight studies.

C-erbB2 (HER-2/neu) plays an important role in the progression of several types of cancer by increasing tumor growth, migration, invasion, and metastasis and is associated with poor disease prognosis. Numerous studies examining the relationship between c-erbB2 expression and prognostic impact in patients with osteosarcoma have yielded inconclusive results. We therefore conducted a meta-analysis to provide a comprehensive evaluation of the prognostic role of c-erbB2 expression on 5-year survival, which compared the positive and negative expression of c-erbB2 in patients of the available studies. A detailed search was made in PubMed for relevant original articles published in English. Finally, a total of eight studies with 411 osteosarcoma patients were involved to estimate the relationship between c-erbB2 expression and 5-year overall survival. Positive expressions of c-erbB2 predicted poorer survival in osteosarcoma with the pooled RR of 1.53 (95 % CI 1.20-1.94, P = 0.0006). In conclusion, the findings from this present meta-analysis suggest that c-erbB2 overexpression is related to poor prognostic of osteosarcoma and can be a useful clinical prognostic factor for those patients.

[FAK/c-Src signaling pathway mediates the expression of cell surface HSP90 in cultured human prostate cancer cells and its association with their invasive capability].

OBJECTIVE: To investigate the expression of heat shock protein 90 (HSP90) on the cell surface of highly invasive human prostate cancer cells PC3 and its possible molecular mechanisms of its effect on cell invasion through analyzing FAK/Src signaling pathway. METHODS: The expression of cell surface HSP90 on PC3 cells was studied by immunofluorescence staining and surface biotinylation assay respectively. A specific HSP90 antibody was used to inhibit the cell surface HSP90. In vitro cell invasion was assessed by modified Boyden chambers. Phosphorylated FAK on tyr 397, 576, 577 and 925, and phosphorylated c-Src on tyr 416 were examined by Western blot assay. The association between FAK and c-Src was analyzed by immunoprecipitation. The effects of FAK knockdown by siRNA or Src kinases inhibitor PP2, with or without anti-HSP90 antibody, on PC3 cell invasion were also evaluated. RESULTS: A pool of HSP90 was detected on the cell surface of PC3 cells. A specific HSP90 antibody significantly retarded tumor cell invasion. Concomitant with this finding, targeting cell surface HSP90 significantly inhibited the phosphorylations of FAK and c-Src, and also the interactions between FAK and c-Src. FAK knockdown or PP2 dramatically suppressed cell invasion, however, anti-HSP90 antibody didn't further inhibit cell invasion. CONCLUSIONS: Cell surface HSP90 promotes human prostate cancer cell invasion through a FAK/c-Src signaling, with may be a novel therapeutic target against metastatic tumors.

Expression of response gene to complement-32 in renal tissue of children with immunoglobulin A nephropathy.

OBJECTIVE: This study aimed to investigate the expression and significance of response gene to complement-32 (RGC-32) in renal tissue of children with immunoglobulin A nephropathy (IgAN). MATERIAL AND METHODS: Forty-five patients diagnosed as having IgAN by renal biopsy were enrolled. The expression of RGC-32, α-smooth muscle actin (α-SMA) and transforming growth factor-ß(1) (TGF-ß(1)) was observed by immunohistostaining. The relationshis between the expression of RGC-32, α-SMA, TGF-ß1, degree of renal pathological lesions in IgAN and clinical index were assessed by Spearman correlation. RESULTS: Immunohistostaining analysis showed that RGC-32 protein was present in epithelial cells of renal tubules in normal and IgAN renal tissues. With more severe renal pathological lesions, the expression of RGC-32 in IgAN was increased. The expression of RGC-32 was positively correlated with that of α-SMA, TGF-ß(1) and the degree of renal pathological lesions in children with IgAN (p < 0.05), but had no relationship with serum creatinine, urinary N-acetyl-ß-d-glucosaminidase/creatinine, urinary microalbuminuria/creatinine, urinary microimmunoglobulin/creatinine or urinary α(1)-microglobulin/creatinine ratio (p > 0.05). CONCLUSION: Expression of RGC-32 can reflect the degree of renal pathological lesions in IgAN. RGC-32 may participate in the renal tubulointerstitial lesions in children with IgAN, especially in epithelial -mesenchymal transition induced by TGF-ß(1).

[Effects of Chinese herbal medicine Huaiqihuang Granule on nephrin and podocin expressions in renal tissues of rats with adriamycin-induced nephrosis].

OBJECT: To investigate the effects of Huaiqihuang Granule, a compound Chinese herbal medicine, on expressions of nephrin and podocin of slit diaphragm of glomerular podocytes in rats with adriamycin-induced nephrosis and to explore the mechanism in reducing the proteinuria. METHODS: Twenty SD rats were randomly divided into five groups: control group, model group, glucocorticoid group, Huaiqihuang Granule group and Huaiqihuang Granule plus glucocorticoid group. The 24-hour urine was collected 7, 14, 21 and 28 days after adriamycin injection respectively to measure 24-hour urinary protein, and all rats were sacrificed after 28-day treatment. Pathological changes in renal tissues were observed under a light microscope and an electron microscope. Expressions of nephrin and podocin mRNAs in renal cortex were determined by real-time polymerase chain reaction, and protein levels of nephrin and podocin were detected by Western blotting. RESULTS: (1) In the model group and the treatment groups, the level of urinary protein increased significantly from the 14th day. (2) Under the light microscope, inflammatory cells and slight fibroplasia were found in renal interstitium of the model group, but there were less inflammatory cells in renal interstitium in the intervention groups than in the model group. Under the electron microscope, 29 days after adriamycin injection, extensive fusion of foot processes was observed. (3) The expressions of nephrin and podocin were higher in treatment groups than in the model group. (4) Proteinuria level was negatively correlated with the expressions of nephrin mRNA and nephrin and podocin proteins. CONCLUSION: The above results indicate that Huaiqihuang Granule can maintain the integrity of the slid diaphragram in podocyte, alleviate the lesion of glomerular filtration membrane, and decrease the proteinuria by up-regulating the expressions of nephrin and podocin. Huaiqihuang Granule plus glucocorticoid maybe has better effects than glucocorticoid alone.

[Effect of interferon-gamma on transforming growth factor beta/Smad signal pathway and expression of matrix metalloproteinase-2 and tissue inhibitors of matrix metalloproteinase-2 in cultured rat mesangial cells].

OBJECTIVE: To study the effect of interferon-gamma (IFN-gamma) on the proliferation of mesangial cells (MsC) and transforming growth factor (TGF)-beta/Smad signal pathway, the mRNA and protein expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase-2 (TIMP-2), and to provide an experimental basis for IFN-gamma treatment of renal fibrosis. METHODS: Cultured MsC were treated with IFN-gamma at different concentrations and the proliferation of MsC was examined by MTT. Protein and RNA samples were extracted from MsC at 0, 0.5, 1, 2, 4, 6, 12, 24 h after treated by 100 IU/ml IFN-gamma. The mRNA and protein expression of Smad3, Smad7, MMP-2 and TIMP-2 were analyzed by real-time RT-PCR and Western blot, respectively. RESULTS: The expression of Smad7 mRNA and protein were promptly elevated at 0.5 hour after the IFN-gamma treatment and lasted for 6 hours, but the proliferation of MsC was not altered. The elevated expression of Smad3, MMP2 mRNA and proteins persisted after 6 hours, whereas the expression of TIMP-2 mRNA and protein decreased. CONCLUSION: The therapeutic effect of IFN-gamma of renal fibrosis may be mediated by TGF-beta/smads signal pathway through up-regulation of MMP-2 expression, coupled with down-regulation of TIMP-2 expression.

Novel gene-modified-tissue engineering of cartilage using stable transforming growth factor-beta1-transfected mesenchymal stem cells grown on chitosan scaffolds.

Rabbit bone marrow-derived mesenchymal stem cells (MSCs) were stably transfected with the TGF-beta1 gene in monolayer culture using Lipofectamine 2000. After transfection, the expression of cartilage-specific extracellular matrix was upregulated, whereas matrix metalloproteinases 1 and 3 (MMP 1 and 3) protein expressions and enzymatic activities were downregulated. Autologous MSCs modified with the TGF-beta1 gene were seeded into chitosan scaffolds to construct gene-modified cartilage, which was then implanted into the full-thickness articular cartilage defects of rabbits' knees. Twelve weeks after implantation, the defects were filled with regenerated hyaline-like cartilage tissue as confirmed by the positive immunohistochemical staining of collagen type II and intense toluidine blue staining of proteoglycan. Our findings suggest that the repair of cartilage defects can be enhanced by TGF-beta1 gene-modified-tissue engineering of cartilage on the basis of a strategy using MSCs, chitosan, and liposomal transfection.

Study on the signalling pathway of inhibitory effect of adreno-medullin on the growth of cultured glomerular mesangial cells.

BACKGROUND: Adrenomedullin (ADM), a potent hypotensive small peptide, was recently found to inhibit the proliferation of glomerular mesangial cells (MsC) in vitro and to attenuate glomerular lesions in vivo, however the mechanisms remain poorly understood. In this study, we attempted to elucidate them using molecular signal transduction. METHODS: Cultured rat MsC were treated with ADM and several inhibitors of signalling molecules. Methyl thiazoleterazolium (MTT) assay and BrdU incorporation method were employed for examining MsC proliferation. Western blot analysis was used for detecting total mitogen activated protein kinases (t-MAPKs) and phosphorylated MAPKs (p-MAPKs) proteins. RESULTS: ADM suppressed MsC proliferation in a concentration- and time-dependent fashion. This response was inhibited by ADM receptor antagonist CGRP8-37 and a potent protein kinase-A (PKA) inhibitor, H89. Forskolin, a direct adenylate cyclase activator, also significantly inhibited MsC proliferation. SB203580, a P38MAPK inhibitor, and U0126, a MEK inhibitor, both completely blocked ADM mediated responses in MsC. However, curcumin, a SAPK/JNK inhibitor, and GF109203X, a potent protein kinase-C (PKC) inhibitor, had no effect on MsC growth. Western blot analysis showed that ADM did not change the expression of t-MAPKs but increased p-SAPK/JNK and p-P38MAPK levels and decreased p-ERK level. These responses were inhibited by CGRP8-37. All these kinase phosphorylations, except for the increase in p-SAPK/JNK, could be stimulated using forskolin. In addition, only ADM mediated changes in ERK and P38MAPK phosphorylations were inhibited by H89. GF109203X did not affect ADM induced changes in three p-MAPKs expressions. CONCLUSIONS: ADM inhibits MsC proliferation possibly through cAMP-PKA pathway. Both phosphorylations of ERK and P38MAPK pathways were necessary in mediating the antiproliferative response of ADM. It does not preclude the involvement of cAMP independent pathways in the ADM mediated responses.

Significance of MMP-2 and TIMP-2 mRNA expressions on glomerular cells in the development of glomerulosclerosis.

OBJECTIVE: To study the expressions of MMP-2 and TIMP-2 mRNA on cultured rat mesangial cells (MsC) and in human diseased glomeruli, and to explore their significance in the development of glomerulosclerosis. METHODS: The expressions of MMP-2, TIMP-2, and Col IV mRNA on cultured rat MsC stimulated by IL-1 or/and TGF-beta1 were investigated through Northern blot analysis. The levels of MMP-2 and TIMP-2 mRNA expressions and immunoreactivity of PCNA and Col IV in human diseased glomeruli from renal biopsies of lupus nephritis (LN) patients were examined by in situ hybridization and immunohistochemistry, respectively. RESULTS: The levels of MMP-2, TIMP-2, and Col IV mRNA expressions were markedly increased on cultured rat MsC stimulated by IL-1 or/and TGF-beta1. Meanwhile, upregulation of MMP-2 and TIMP-2 mRNA expressions was confirmed in diseased glomeruli from patients with various subtypes of LN, and was closely related to the positive cell number of PCNA presentation and deposition of Col IV in glomeruli. CONCLUSION: The results suggest that the over-expressions of MMP-2 and TIMP-2 mRNA on glomerular cells might play a critical role in the development of glomerulosclerosis.

[The antagonistic effect on anti-thy-1 serum-induced nephritis of rats injected by decorin-transfected mesangial cells vector].

OBJECTIVES: To inject decorin-transfected mesangial cells (MsC) vector into the kidneys of rats with anti-thy-1 serum-induced nephritis via left renal artery and observe the survival condition of MsC vector and its influence on glomerular lesions in rats with anti-thy-1 serum induced nephritis. METHODS: Rat mesangio-proliferative glomerulonephritis was established by tail intravenous injection with rabbit anti-thy-1 serum (ATS). Decorin-transfected MsC was injected into rat kidneys via left renal artery. Primary culture, immunostaining for BrdU and decorin of transfected MsC lines were performed to observe their survival. Immunohistochemistry with image analysis was performed to detect the expression of BrdU, alpha-SMA, decorin, TGF-beta1, FN and ColIV in diseased glomeruli. RESULTS: Rat anti-thy-1 serum-induced nephritis identified by pathological examination was successfully established by injecting rabbit ATS, and decorin transfected MsC vector was transfused to rat glomeruli via left renal artery. The active growth and positive expressions of BrdU and decorin proteins on the nuclei and cytoplasms of ex vivo MsC were observed respectively. TGF-beta1, FN, ColIV expressions in diseased glomeruli of rats with ATS nephritis were decreased significantly at day 4 (TGF-beta1, P < 0.05) and day 2 (FN and ColIV, P < 0.01) respectively, compared to uninjected kidneys. CONCLUSIONS: MsC vector is successfully transferred to the glomeruli of experimental rats via left renal artery injection with no affect on cell survival. Decorin protein is expressed on the transfected MsC and shows antagonistic effect on the glomerular lesions of ATS rats. It suggests that the use of ex vivo MsC vector system can provide useful experimental basis for gene therapy of kidney disease in animal model.

[Effect of transforming growth factor beta1/Smad signaling pathway on the expression and enzymatic activity of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in cultured rat mesangial cells].

OBJECTIVE: To explore the effect of transforming growth factor (TGF) beta1/Smad signaling pathway on the expression and enzymatic activity of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in cultured rat mesangial cells (MsC). METHODS: Lipofectin method was used to transfect Smad 2, Smad 3 and Smad 7 vectors into MsC; and immunofluorescence, RT-PCR and Western blot analysis were used to detect their transfection efficiency. The expression and enzymatic activity of MMP-2 and TIMP-2 were determined by Western blot, zymography or reverse zymography assay. RESULTS: MsC transfected with Smad 2 gene showed slightly increased expression and enzymatic activity of both MMP-2 and TIMP-2, which was more obvious upon stimulation by TGF-beta1. MsC transfected with Smad 3 gene showed a slight upregulation of TIMP-2 expression and its enzymatic activity, which was enhanced after TGF-beta1 stimulation. There was however no change in MMP-2 expression and its enzymatic activity. On the other hand, MsC transfected with Smad 7 gene showed a decrease in MMP-2 and TIMP-2 expression and enzymatic activity, which was especially obvious after stimulation by TGF-beta1. CONCLUSIONS: TGF-beta1/Smad signaling pathway may play an important role in the pathogenesis of glomerulosclerosis, probably via MMP-2 and TIMP-2 expression and the associated enzymatic activity.