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111.
Development of induced pluripotent stem cell (iPSC) technology introduced a novel way to derive pluripotent stem cells, but the genetic manipulation required to generate iPSCs may lead to uncontrolled tumorigenesis of the established cells and thus limit clinical feasibility of the technology. Numerous attempts have been made to date, and alternative reprogramming of somatic cells to reactivate cellular plasticity after differentiation has been suggested. As a result, it had become clear that cell-to-cell interactions and specific acellular environments can be utilized for somatic cell reprogramming. In our previous studies, embryonic stem cell (ESC)-like cells could be derived from transforming ovarian cells and fetal fibroblasts by cell-to-cell interaction or specific cell-mediated microenvironmental factor(s). This cellular event was induced without undertaking genetic manipulation of progenitor cells. Several differences were found between the cellular properties of niche-induced, ESC-like cells and those of genetically manipulated iPSCs and the referenced ESCs. Thus, we provided evidence that terminally differentiated somatic cells either acquire pluripotency-like activity or possess cellular and genetic plasticity under a specific microenvironment and/or cell-to-cell interaction. In this minireview, we discuss derivation of stem cell-like cells under specific microenvironmental conditions in terms of technical perspectives and limitations.  相似文献   
112.

Background

Microalbuminuria is associated with increased risk of renal disease and cardiovascular diseases even in non-diabetic subjects. High incidence rates of microalbuminuria have been found in a number of population-based studies. However, the prevalence and risk factors associated with microalbuminuria in the general population in Korea are unclear.

Objectives

The present study was performed to estimate the prevalence of microalbuminuria and investigate the associated risk factors in the general adult population using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-2) data from 2011.

Methods

A total of 5,202 participants (mean age, 45.6 years; men, 2,337; women, 2,865) were included in the analysis. Microalbuminuria was evaluated in participants of KNHANES V-2 based on the urine albumin–creatinine ratio. Estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease study equation.

Results

The weighted prevalence of microalbuminuria was 5.2% (95% CI, 4.4–6.1) in the general population. The prevalence of albuminuria is increased with age. After adjustment for age and sex, the presence of albuminuria was associated with increased waist circumference, systolic and diastolic blood pressure, aspartate aminotransferase, triglyceride, fasting plasma glucose, and the presence of hypertension and diabetes. In logistic regression analyses, older age, female sex, diabetes, hypertension, and serum aspartate aminotransferase were independently associated with the presence of albuminuria.

Conclusion

The prevalence of microalbuminuria was found to be 5.2%, and conventional risk factors for cardiovascular diseases are closely related to the presence of microalbuminuria in Korea. Microalbuminuria may be a useful marker to identify individuals with increased risk of cardiovascular disease.  相似文献   
113.

Background

The objective of this study was to determine whether acute histologic chorioamnionitis is associated with adverse neonatal outcomes in late preterm infants who were born after preterm PROM.

Methodology/Principal Findings

The relationship between the presence of acute histologic chorioamnionitis and adverse neonatal outcome was examined in patients with preterm PROM who delivered singleton preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Nonparametric statistics were used for data analysis. The frequency of acute histologic chorioamnionitis was 24% in patients with preterm PROM who delivered preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Newborns born to mothers with histologic chorioamnionitis had significantly higher rates of adverse neonatal outcome (74% vs 51%; p<0.005) than those without histologic chorioamnionitis. This relationship remained significant after adjustment for gestational age at preterm PROM, gestational age at delivery, and exposure to antenatal corticosteroids.

Conclusions/Significance

The presence of acute histologic chorioamnionitis is associated with adverse neonatal outcome in late preterm infants born to mothers with preterm PROM.  相似文献   
114.
Type 1 diabetes mellitus (T1DM) usually begins in childhood and adolescence and causes lifelong damage to several major organs including the brain. Despite increasing evidence of T1DM-induced structural deficits in cortical regions implicated in higher cognitive and emotional functions, little is known whether and how the structural connectivity between these regions is altered in the T1DM brain. Using inter-regional covariance of cortical thickness measurements from high-resolution T1-weighted magnetic resonance data, we examined the topological organizations of cortical structural networks in 81 T1DM patients and 38 healthy subjects. We found a relative absence of hierarchically high-level hubs in the prefrontal lobe of T1DM patients, which suggests ineffective top-down control of the prefrontal cortex in T1DM. Furthermore, inter-network connections between the strategic/executive control system and systems subserving other cortical functions including language and mnemonic/emotional processing were also less integrated in T1DM patients than in healthy individuals. The current results provide structural evidence for T1DM-related dysfunctional cortical organization, which specifically underlie the top-down cognitive control of language, memory, and emotion.  相似文献   
115.

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   
116.
Newcastle disease (ND) is one of the most devastating poultry infections because of its worldwide distribution and accompanying economical threat. In the present study, we characterized the ND virus (NDV) K148/08 strain from wild mallard duck, with regard to safety, thermostability, immunogenicity, and protective efficacy against velogenic ND viral infection. The NDV K148/08 strain offered enhanced immunogenicity and safety relative to commercially available vaccine strains. The NDV K148/08 strain was safe in 1-day-old SPF chicks after vaccination using a coarse or cabinet-type fine sprayer. We demonstrated that the NDV K148/08 strain elicited high levels of antibody responses and provided protective efficacy against lethal NDV challenge. In addition, the thermostability of the NDV K148/08 strain was as high as that of the thermostable V4 strain. Therefore, the NDV K148/08 strain may be useful to ensure NDV vaccine performance and effectiveness in developing countries, especially in remote areas without cold chains.  相似文献   
117.
Embden-Meyerhof pathway (EMP) in tandem with 2-C-methyl-D-erythritol 4-phosphate pathway (MEP) is commonly used for isoprenoid biosynthesis in E. coli. However, this combination has limitations as EMP generates an imbalanced distribution of pyruvate and glyceraldehyde-3-phosphate (G3P). Herein, four glycolytic pathways—EMP, Entner-Doudoroff Pathway (EDP), Pentose Phosphate Pathway (PPP) and Dahms pathway were tested as MEP feeding modules for isoprene production. Results revealed the highest isoprene production from EDP containing modules, wherein pyruvate and G3P were generated simultaneously; isoprene titer and yield were more than three and six times higher than those of the EMP module, respectively. Additionally, the PPP module that generates G3P prior to pyruvate was significantly more effective than the Dahms pathway, in which pyruvate production precedes G3P. In terms of precursor generation and energy/reducing-equivalent supply, EDP+PPP was found to be the ideal feeding module for MEP. These findings may launch a new direction for the optimization of MEP-dependent isoprenoid biosynthesis pathways.  相似文献   
118.
Protein tyrosine phosphatases play key roles in a diverse range of cellular processes such as differentiation, cell proliferation, apoptosis, immunological signaling, and cytoskeletal function. Protein tyrosine phosphatase non-receptor type 7 (PTPN7), a member of the phosphatase family, specifically inactivates mitogen-activated protein kinases (MAPKs). Here, we report that PTPN7 acts as a regulator of pro-inflammatory TNF-α production in RAW 264.7 cells that are stimulated with lipopolysaccharide (LPS) that acts as an endotoxin and elicits strong immune responses in animals. Stimulation of RAW 264.7 cells with LPS leads to a transient decrease in the levels of PTPN7 mRNA and protein. The overexpression of PTPN7 inhibits LPS-stimulated production of TNF-α. In addition, small interfering RNA (siRNA) analysis showed that knock-down of PTPN7 in RAW 264.7 cells increased TNF-α production. PTPN7 has a negative regulatory function to extracellular signal regulated kinase 1/2 (ERK1/2) and p38 that increase LPS-induced TNF-α production in macrophages. Thus, our data presents PTPN7 as a negative regulator of TNF-α expression and the inflammatory response in macrophages.  相似文献   
119.
BACKGROUND: Clear cell renal cell carcinoma (CRCC) is the most common malignant tumor of the kidney, and the clinical outcome of CRCC is related with the metastatic potential of CRCC. A significant proportion of metastatic CRCC remains incurable. Recently, immunotherapy against specific targets such as programmed death 1 (PD1) has been adapted for fatal cases of CRCC. MATERIALS AND METHODS: In this study, we aimed to evaluate the potential of tumor-infiltrating PD1-positive lymphocytes or FoxP3-positive regulatory T cells (Tregs) as predictors of the metastatic potential or prognosis of CRCC and investigate possible correlations with Epstein-Barr virus (EBV) infection in 199 cases of CRCC. RESULTS: PD1 positivity, high Treg number, and EBV infection all predicted poor overall survival (OS) by univariate analysis. PD1 positivity and high Treg numbers were also significantly correlated with more distant metastatic relapse (DMR) and poor relapse-free survival (RFS) by univariate analysis. PD1 positivity and high Treg number were independent prognostic indicators for OS. In addition, PD1 positivity was an independent predictor of RFS and DMR. EBV infection was an independent predictor of OS of CRCC. CONCLUSION: This study demonstrates that intratumoral infiltration of PD1-positive or FoxP3-positive lymphocytes can be used as significant prognostic indicators of CRCC and PD1 positivity could be very helpful in the prediction of latent distant metastasis of CRCCs. Therefore, evaluation of the infiltration of PD-positive cells or Tregs in CRCC may be useful diagnostic tools for the selection of patients who could benefit from PD1- or Treg-based immunotherapy.  相似文献   
120.
BACKGROUND: Recently, deleted in breast cancer 1 (DBC1) has been suggested as a poor prognostic indicator of various human cancers and may possibly have a role as a coactivator of androgen receptor (AR). However, their roles in lymphoma are still unknown. MATERIALS AND METHODS: We investigated the effect of the expression of DBC1 and AR in diffuse large B cell lymphoma (DLBCL). Immunohistochemical expression of DBC1 and AR were evaluated in 101 DLBCL samples by tissue microarray. RESULTS: Positive expression of DBC1 and AR was seen in 73% and 70% of DLBCL, respectively. In total DLBCL patients, DBC1 and AR expression were significantly associated with high clinical stage, elevated serum lactate dehydrogenase levels, and high international prognostic index scores, and they predicted shorter overall survival (OS) and relapse-free survival (RFS) by univariate analysis. DBC1 expression was also an independent prognostic indicator by multivariate analysis (OS, P = .017; RFS, P = .004). Especially, both DBC1 and AR expression significantly correlated with shorter OS and RFS in non-germinal center B cell (non-GCB)-type DLBCL by univariate analysis. In multivariate analysis, DBC1 expression was an independent prognostic predictor for OS (P = .035) and AR expression significantly correlated with RFS (P = .005). CONCLUSION: We demonstrate that the expression of DBC1 and AR are significant prognostic indicators for DLBCL patients, especially for unfavorable non-GCB-type DLBCL.  相似文献   
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