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601.
Diabet. Med. 29, e398-e401 (2012) ABSTRACT: Background We describe an unplanned pregnancy in a 19-year-old with lipodystrophic diabetes caused by a mutation in the peroxisome proliferator-activated receptor gamma (PPARG) gene. The pregnancy was complicated by poor compliance with treatment, severe hypertriglyceridaemia and pancreatitis. Case report The patient presented at 6?weeks' gestation with an HbA(1c) of 140?mmol/mol (15%), cholesterol 8.1?mmol/l and triglycerides 20.1?mmol/l. She wished to continue the pregnancy so lipid-lowering therapy was discontinued. She was severely insulin resistant and poorly compliant with diet and medication. A continuous subcutaneous insulin infusion was required for efficient delivery of large doses of basal insulin, alongside injected mealtime boluses, (up to 300?units insulin per day). At 17?weeks' gestation she developed acute pancreatitis secondary to hypertriglyceridaemia (triglycerides >?100?mmol/l) and required plasmapheresis. Lipid-lowering therapy was reinstated in the third trimester and plasmapheresis was required repeatedly to maintain triglycerides 相似文献   
602.
Ha CW  Noh MJ  Choi KB  Lee KH 《Cytotherapy》2012,14(2):247-256
Background aimsTissueGene-C (TG-C) represents a cell-mediated gene therapy for localized delivery of allogeneic chondrocytes expressing transforming growth factor (TGF)-β1 directly to the damaged knee joint. Untransduced human chondrocytes (hChonJ cells) have also been incorporated into the TG-C product at a 3:1 ratio with TGF-β1-expressing chondrocytes (hChonJb#7) in order to help fill in the defect and as target cells for the actions of the expressed TGF-β1.MethodsA phase I dose-escalating clinical trial was performed to evaluate the safety and biologic activity of TG-C in patients with advanced osteoarthritis of the knee joint (full thickness cartilage defect) that was refractory to existing non-operative therapies. Following a single intra-articular injection into the joint space of the damaged knee, patients were monitored for safety, and an evaluation was performed to assess the pharmacokinetics and biologic activity of TG-C.ResultsThere were no treatment-related serious adverse events. Swelling, effusion and minor localized reactions such as warming sensation or itching were observed in a dose-dependent manner at the injection site. Knee evaluation scores seemed to indicate a dose-dependent trend toward efficacy; however, patient numbers were not sufficient to determine statistical significance.ConclusionsOverall, there were no significant safety issues related to the administration of TG-C, with only some minor injection site reactions observed. Additionally, knee scoring analyzes indicated a possibility that TG-C may contribute to improvement of arthritic symptoms. More study is warranted to evaluate further the safety and determine the potential efficacy of TG-C.  相似文献   
603.
The generation of induced pluripotent stem (iPS) cells is a powerful tool in regenerative medicine, and advances in nanotechnology clearly have great potential to enhance stem cell research. Here, we introduce a liposomal magnetofection (LMF) method for iPS cell generation. Efficient conditions for generating virus-free iPS cells from mouse embryonic fibroblast (MEF) cells were determined through the use of different concentrations of CombiMag nanoparticle-DNA(pCX-OKS-2A and pCX-cMyc)-lipoplexes and either one or two cycles of the LMF procedure. The cells were prepared in a short reprogramming time period (≤8 days, 0.032–0.040%). Among the seven LMF-iPS cell lines examined, two were confirmed to be integration-free, and an integration-free LMF-iPS cell line was produced under the least toxic conditions (single LMF cycle with a half-dose of plasmid). This cell line also displayed in vitro/in vivo pluripotency, including teratoma formation and chimeric mouse production. In addition, the safety of CombiMag-DNA lipoplexes for the transfection of MEF cells was confirmed through lactate dehydrogenase activity assay and transmission electron microscopy. These results demonstrated that the LMF method is simple, effective, and safe. LMF may represent a superior technique for the generation of virus-free or integration-free iPS cell lines that could lead to enhanced stem cell therapy in the future.  相似文献   
604.
NADPH oxidase (NOX) is a predominant source of reactive oxygen species (ROS), and the activity of NOX, which uses NADPH as a common rate-limiting substrate, is upregulated by prolonged dietary salt intake. β-Lapachone (βL), a well-known substrate of NAD(P)H:quinone oxidoreductase 1 (NQO1), decreases the cellular NAD(P)H/NAD(P)(+) ratio via activation of NQO1. In this study, we evaluated whether NQO1 activation by βL modulates salt-induced renal injury associated with NOX-derived ROS regulation in an animal model. Dahl salt-sensitive (DS) rats fed a high-salt (HS) diet were used to investigate the renoprotective effect of NQO1 activation. βL treatment significantly lowered the cellular NAD(P)H:NAD(P)(+) ratio and dramatically reduced NOX activity in the kidneys of HS diet-fed DS rats. In accordance with this, total ROS production and expression of oxidative adducts also decreased in the βL-treated group. Furthermore, HS diet-induced proteinuria and glomerular damage were markedly suppressed, and inflammation, fibrosis, and apoptotic cell death were significantly diminished by βL treatment. This study is the first to demonstrate that activation of NQO1 has a renoprotective effect that is mediated by NOX activity via modulation of the cellular NAD(P)H:NAD(P)(+) ratio. These results provide strong evidence that NQO1 might be a new therapeutic target for the prevention of salt-induced renal injury.  相似文献   
605.
Xanthomonas oryzae pv. oryzae causes bacterial blight in rice, and this bacterial blight has been widely found in the major rice-growing areas. We constructed a transposon mutagenesis library of X. oryzae pv. oryzae and identified a mutant strain (KXOM9) that is deficient for pigment production and virulence. Furthermore, the KXOM9 mutant was unable to grow in minimal medium lacking aromatic amino acids. Thermal asymmetric interlaced-PCR and sequence analysis of KXOM9 revealed that the transposon was inserted into the aroC gene, which encodes a chorismate synthase in various bacterial pathogens. In planta growth assays revealed that bacterial growth of the KXOM9 mutant in rice leaves was severely reduced. Genetic complementation of this mutant with a 7.9-kb fragment containing aroC restored virulence, pigmentation, and prototrophy. These results suggest that the aroC gene plays a crucial role in the growth, attenuation of virulence, and pigment production of X. oryzae pv. oryzae.  相似文献   
606.
Previously, we have shown that green tea extract (GTE) lowers the intestinal absorption of lipids and lipophilic compounds in rats. This study was conducted to investigate whether GTE inhibits the intestinal absorption and biliary secretion of benzo[a]pyrene (BaP), an extremely lipophilic potent carcinogen, present in foods as a contaminant. Male rats with lymph or bile duct cannula were infused at 3.0 ml/h for 8 h via a duodenal catheter with lipid emulsion containing (14)C-BaP with or without GTE in PBS buffer. Lymph and bile were collected hourly for 8 h. The (14)C-radioactivities in lymph, bile and intestine were determined and expressed as % dose infused. Results showed that GTE drastically lowered the lymphatic absorption of (14)C-BaP (7.6±3.2% in GTE-infused vs. 14.4±2.7% dose/8 h in control rats), with a significantly higher amount of (14)C-radioactivity present in the small intestinal lumen and cecum in rats infused with GTE. GTE also markedly increased the hourly rate (3.9±0.1% dose/h in GTE-infused vs. 3.0±0.1% dose/h in control rats) and the total biliary secretion of (14)C-BaP (31.5±0.8% dose/8 h in GTE-infused vs. 24.3±0.4% dose/8 h in control rats). The findings provide first direct evidence that GTE has a profound inhibitory effect on the intestinal absorption of BaP and promotes the excretion of absorbed BaP via the biliary route. Further studies are warranted to investigate whether green tea could be recommended as a dietary means of ameliorating the toxicity and carcinogenic effect of BaP.  相似文献   
607.
The amperometric immunosensor has demonstrated the toxicity of endocrine disrupters (EDs) through monitoring the in vitro i-NOS concentration change, where the antibody of inducible nitric oxide synthase (i-NOS) was immobilized on the conducting polymer-gold nanoparticles composite. The performance of the sensor and the experimental parameters affecting the immunoreaction were optimized. Neuronal cells treated by EDs decreased in the in vitro i-NOS concentration. The effect of bisphenol A (BPA) on the i-NOS concentration released in the cells was investigated with different incubation times, and the interfering by nonspecific binding species present in a neuronal cell lysate was also examined. Of all the tested EDs, BPA showed the inhibitoriest effect and the minimum inhibitory concentration of BPA affecting the i-NOS concentration was 0.09 ± 0.005 μM. The result shows that monitoring of i-NOS in the neuronal cells treated by EDs will be a useful method to evaluate the toxic behavior of EDs.  相似文献   
608.
609.
Autophagy, a self-eating process, is responsible for degradation of long-lived proteins and damaged cellular proteins/organelles. Double-membrane autophagosomes, formed during the process, engulf proteins/organelles and fuse with lysosomes to degrade the contents. It is important to maintain cell homeostasis and many physiological processes including cellular responses to oxidative stress. Oxidative stress induced by myocardial infarction is a major factor of heart failures. In this study, we examined how propofol modulates hydrogen peroxide (H2O2)-induced autophagic cell death in H9c2 cardiomyocytes. H2O2 dramatically induced cell death, which was similarly reduced in the presence of either propofol or autophagy inhibitors (e.g., wortmannin), suggesting that propofol has a protective effect in H2O2-induced autophagic cell death. Acidic autophagic vacuoles were elevated in H2O2-treated H9c2 cells, but they were largely decreased in the presence of propofol. Furthermore, many autophagy-related proteins such as LC3-II, ATG proteins, p62, AMPK, and JNK were activated in H2O2-treated H9c2 cells and were significantly deactivated in the presence of propofol. These results show that propofol regulates oxidative stress-induced autophagic cell death in cardiomyocytes. We further suggest that propofol can act as a cardioprotectant in heart diseases.  相似文献   
610.
Glycogen synthase kinase-3 (GSK-3) modulates a wide array of cellular processes, including embryonic development, cell differentiation, survival, and apoptosis. Recently, it was reported that a GSK-3 inhibitor attenuates lipopolysaccharide (LPS)-induced septic shock and regulates the mortality of endotoxemic mice. However, the detailed mechanism of reduced mortality via GSK-3 inhibition is not well defined. Herein, we showed that GSK-3 inhibition induces extracellular signal-regulated kinase 1/2 (ERK1/2) activation under LPS-stressed conditions via protein kinase C δ (PKCδ) activation. Furthermore, PKCδ-induced ERK1/2 activation by the inhibition of GSK-3 provoked the production of interleukin (IL)-10, playing a crucial role in regulating endotoxemia. Using a mitogen-activated protein kinase kinase-1 (MEK-1) and PKCδ inhibitor, we confirmed that GSK-3 inhibition induces PKCδ and subsequent ERK1/2 activation, resulting in increased IL-10 expression under LPS-treated conditions. We verified that septic shock caused by LPS is attenuated by GSK-3 inhibition using a GSK-3 inhibitor. This relieved endotoxemia induced by GSK-3 inhibition was restored in an ERK1/2-dependent manner. Taken together, IL-10 expression produced by GSK-3 inhibition-induced ERK1/2 activation via PKCδ relieved LPS-mediated endotoxemia. This finding suggests that IL-10 hyperexpression resulting from GSK-3 inhibition-induced ERK activation could be a new therapeutic pathway for endotoxemia.  相似文献   
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