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151.

Background

The protective effects of granulocyte colony-stimulating factor (G-CSF) have been demonstrated in a variety of renal disease models. However, the influence of G-CSF on diabetic nephropathy (DN) remains to be examined. In this study, we investigated the effect of G-CSF on DN and its possible mechanisms in a rat model.

Methods

Otsuka Long-Evans Tokushima Fatty (OLETF) rats with early DN were administered G-CSF or saline intraperitoneally. Urine albumin creatinine ratio (UACR), creatinine clearance, mesangial matrix expansion, glomerular basement membrane (GBM) thickness, and podocyte foot process width (FPW) were measured. The levels of interleukin (IL)-1β, transforming growth factor (TGF)-β1, and type IV collagen genes expression in kidney tissue were also evaluated. To elucidate the mechanisms underlying G-CSF effects, we also assessed the expression of G-CSF receptor (G-CSFR) in glomeruli as well as mobilization of bone marrow (BM) cells to glomeruli using sex-mismatched BM transplantation.

Results

After four weeks of treatment, UACR was lower in the G-CSF treatment group than in the saline group (p<0.05), as were mesangial matrix expansion, GBM thickness, and FPW (p<0.05). In addition, the expression of TGF-β1 and type IV collagen and IL-1β levels was lower in the G-CSF treatment group (p<0.05). G-CSFR was not present in glomerular cells, and G-CSF treatment increased the number of BM-derived cells in glomeruli (p<0.05).

Conclusions

G-CSF can prevent the progression of DN in OLETF rats and its effects may be due to mobilization of BM cells rather than being a direct effect.  相似文献   
152.
The anti-inflammatory activity of eriodictyol and its mode of action were investigated. Eriodictyol suppressed tumor necrosis factor (mTNF)-α, inducible nitric oxide synthase (miNOS), interleukin (mIL)-6, macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine release in LPS-stimulated macrophages. We found that the anti-inflammatory cascade of eriodictyol is mediated through the Toll-like Receptor (TLR)4/CD14, p38 mitogen-activated protein kinases (MAPK), extracellular-signalregulated kinase (ERK), Jun-N terminal kinase (JNK), and cyclooxygenase (COX)-2 pathway. Fluorescence quenching and saturation-transfer difference (STD) NMR experiments showed that eriodictyol exhibits good binding affinity to JNK, 8.79 × 105 M-1. Based on a docking study, we propose a model of eriodictyol and JNK binding, in which eriodictyol forms 3 hydrogen bonds with the side chains of Lys55, Met111, and Asp169 in JNK, and in which the hydroxyl groups of the B ring play key roles in binding interactions with JNK. Therefore, eriodictyol may be a potent anti-inflammatory inhibitor of JNK. [BMB Reports 2013; 46(12): 594-599]  相似文献   
153.
In the present study, we screened proteomic and cytokine biomarkers between patients with adenomatous polyps and colorectal cancer (CRC) in order to improve our understanding of the molecular mechanisms behind turmorigenesis and tumor progression in CRC. To this end, we performed comparative proteomic analysis of plasma proteins using a combination of 2DE and MS as well as profiled differentially regulated cytokines and chemokines by multiplex bead analysis. Proteomic analysis identified 11 upregulated and 13 downregulated plasma proteins showing significantly different regulation patterns with diagnostic potential for predicting progression from adenoma to carcinoma. Some of these proteins have not previously been implicated in CRC, including upregulated leucine‐rich α‐2‐glycoprotein, hemoglobin subunit β, Ig α‐2 chain C region, and complement factor B as well as downregulated afamin, zinc‐α‐2‐glycoprotein, vitronectin, and α‐1‐antichymotrypsin. In addition, plasma levels of three cytokines/chemokines, including interleukin‐8, interferon gamma‐induced protein 10, and tumor necrosis factor α, were remarkably elevated in patients with CRC compared to those with adenomatous polyps. Although further clinical validation is required, these proteins and cytokines can be established as novel biomarkers for CRC and/or its progression from colon adenoma.  相似文献   
154.
Follicular populations were investigated in female F344/N rats to better understand the aging process of the rat ovary. Ovaries dissected at various ages (spanning 1–36 months old) were submitted for histological examination. The total number of primordial, growing (primary and secondary), tertiary, and atretic follicles as well as corpora lutea (CL) were counted in hematoxylin–eosin- and azocarmine–aniline-blue-stained ovarian sections. The number of healthy follicles including primordial, growing and tertiary follicles decreased rapidly between the first and third months and gradually thereafter. CL were found in 3-month-old rats, and their number remained unchanged until 18 months of age, at which point it decreased. The number of atretic follicles started to increase in rats older than 18 months, which corresponded to the cessation of estrous cyclicity. Several healthy follicles and CL were observed even in 36-month-old rats.  相似文献   
155.
In this study, nuclear magnetic resonance techniques coupled with multivariate data analysis were used for the metabolic profiling of mycelia and fruiting bodies of the entomopathogenic fungi, Cordyceps bassiana according to developmental stages. A direct extraction method using two deuterated solvents of D2O and CDCl3 was used to investigate the relative levels of identified metabolites in each extraction condition in the mycelium and fruiting body formation stages. There was a clear separation among mycelia and fruiting bodies with various developmental stages in partial least-squares discriminant analysis (PLS-DA) derived score plots. During the transition from mycelia to fruiting bodies, the major metabolic change observed was the conversion of glucose to mannitol, and beauvericin to phenylalanine and 1-hydroxyisovaleric acid. In the developmental stages of fruiting bodies studied, there was a clear separation between stage 3 and the other stages in PLS-DA derived score plots. Nineteen compounds including 13 amino acids, 2 nucleosides, 3 organic acids, and glucose showed the highest levels in stage 3 fruiting bodies. The flavonoid content in the fruiting bodies showed similar levels during stages 1, 2, and 3, whereas the level at stage 4 was significantly decreased compared to the other stages. Results suggest that the fruiting body of C. bassiana is richer in natural resources at stage 3 compared to the other fruiting body stages due to its high abundance of compounds including total flavonoids. The metabolome information acquired in this study can be useful criteria for the quality control of commercial use of C. bassiana.  相似文献   
156.
Two closely related bacterial species, Segniliparus rotundus and Segniliparus rugosus, have emerged as important human pathogens, but little is known about the immune responses they elicit or their comparative pathophysiologies. To determine the virulence and immune responses of the two species, we compared their abilities to grow in phagocytic and non-phagocytic cells. Both species maintained non-replicating states within A549 epithelial cells. S. rugosus persisted longer and multiplied more rapidly inside murine bone marrow-derived macrophages (BMDMs), induced more pro-inflammatory cytokines, and induced higher levels of macrophage necrosis. Activation of BMDMs by both species was mediated by toll-like receptor 2 (TLR2), followed by mitogen-activated protein kinases (MAPK) and nuclear factor κB (NF-κB) signaling pathways, indicating a critical role for TLR2 in Segniliparus-induced macrophage activation. S. rugosus triggered faster and stronger activation of MAPK signaling and IκB degradation, indicating that S. rugosus induces more pro-inflammatory cytokines than S. rotundus. Multifocal granulomatous inflammations in the liver and lung were observed in mice infected with S. rugosus, but S. rotundus was rapidly cleared from all organs tested within 15 days post-infection. Furthermore, S. rugosus induced faster infiltration of innate immune cells such as neutrophils and macrophages to the lung than S. rotundus. Our results suggest that S. rugosus is more virulent and induces a stronger immune response than S. rotundus.  相似文献   
157.

Objective

Our study aims to describe changes in carcinoma in situ (CIS) and invasive cervical carcinoma (ICC) in Korean women diagnosed between 1993 and 2009.

Methods

All cases of CIS and invasive cervical carcinoma diagnosed from 1993 to 2009 in the Korean National Cancer Incidence database were analyzed. Age-standardized rates (ASRs) and annual percent changes (APCs) in incidence rates were compared according to age and histological type. Additionally, we used Korea National Health and Nutrition Examination Survey (KNHANES) to know the association between screening rate for cervical cancer and incidence rate of cervical cancer.

Results

Between 1993 and 2009, 72,240 cases of ICC were reported in Korea. Total incidence rate of ICC was 14.7 per 100,000 females. ASRs of ICC declined 3.8% per year, from 19.3 per 100,000 in 1993 to 10.5 per 100,000 in 2009. Although the overall incidence rate of adenocarcinoma remained stable, invasive squamous cell carcinoma showed a decreasing trend (APC −4.2%). For women aged 60–79 years, ASRs for squamous cell carcinoma increased from 1993 to 2001, and decreased from 2001 to 2009 (APC: −4.6%). Total 62,300 cases of CIS were diagnosed from 1993 to 2009. Total incidence rate of CIS was 12.2 per 100,000 females. ASRs of CIS increased 5.7% per year, from 7.5 per 100,000 in 1993 to 19.0 per 100,000 in 2009. Adenocarcinoma in situ increased 13.2% per year. There was a strong positive correlation between screening rate for cervical cancer and incidence rate for CIS (p-value = 0.03) whereas screening rate showed a strong negative correlation with incidence rate for squamous ICC (p-value = 0.04).

Conclusions

The increasing trend in CIS, coupled with a decreasing trend in ICC, suggests the important role of cervix cancer screening. The incidence of adenocarcinoma showed a plateau, but the incidence of adenocarcinoma in situ showed an increasing trend.  相似文献   
158.
159.
The mechanisms by which B lymphocytes inhibit anti-tumor immunity remain poorly understood. Murine EMT-6 mammary tumors grow readily in immune competent mice (BALB/c), but poorly in B-cell-deficient μ?/? BALB/c mice (BCDM). T regulatory cell (Treg) expansion and function were impaired in BCDM compared with BALB/c. In this study, we compared tumor growth, Treg cell proliferation, tumor lymphocyte infiltration and cytolytic T cell activity in BALB/c, BCDM and BCDM partially reconstituted with B cells by adoptive transfer (BCDM+B). Partial reconstitution of BCDM with adoptively transferred B cells restored EMT-6 tumor growth, which was independent of IL-10 secretion by B cells. Instead, high frequencies of intratumoral B cells were associated with increased recruitment and proliferation of Treg cells within the tumor microenvironment. The B-cell-dependent accumulation of Treg within the tumor microenvironment was associated with reduced tumor infiltration by CD49+ NK and CD8+ T cells and reduced cytotoxic T cell activity against EMT-6 targets. Our studies indicate that tumor-dependent immunosuppression of T-cell-mediated anti-tumor immunity is coordinated within the tumor microenvironment by B-cell-dependent cross talk with Treg cells, which does not require production of IL-10 by B cells.  相似文献   
160.
Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system.  相似文献   
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