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Transforming growth factor β (TGFβ) causes the acquisition of epithelial–mesenchymal transition (EMT). Although the tumor suppressor gene PTEN (phosphatase and tensin homologue deleted from chromosome 10) can negatively regulate many signaling pathways activated by TGFβ, hyperactivation of these signaling pathways is observed in lung cancer cells. We recently showed that PTEN might be subject to TGFβ‐induced phosphorylation of its C‐terminus, resulting in a loss of its enzyme activities; PTEN with an unphosphorylated C‐terminus (PTEN4A), but not PTEN wild, inhibits TGFβ‐induced EMT. Nevertheless, whether or not the blockade of TGFβ‐induced EMT by the PTEN phosphatase activity might be attributed to the unphosphorylated PTEN C‐terminus itself has not been fully determined. Furthermore, the lipid phosphatase activity of PTEN is well characterized, whereas the protein phosphatase activity has not been determined. By using lung cancer cells carrying PTEN domain deletions or point mutants, we investigated the role of PTEN protein phosphatase activities on TGFβ‐induced EMT in lung cancer cells. The unphosphorylated PTEN C‐terminus might not directly retain the phosphatase activities and repress TGFβ‐induced EMT; the modification that keeps the PTEN C‐terminus not phosphorylated might enable PTEN to retain the phosphatase activity. PTEN4A with G129E mutation, which lacks lipid phosphatase activity but retains protein phosphatase activity, repressed TGFβ‐induced EMT. Furthermore, the protein phosphatase activity of PTEN4A depended on an essential association between the C2 and phosphatase domains. These data suggest that the protein phosphatase activity of PTEN with an unphosphorylated C‐terminus might be a therapeutic target to negatively regulate TGFβ‐induced EMT in lung cancer cells.  相似文献   
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Aim: Recent studies have demonstrated that selective sodium–glucose cotransporter 2 inhibitors (SGLT2is) reduce cardiovascular events, although their mechanism remains obscure. We examined the effect of canagliflozin, an SGLT2i, on atherogenesis and investigated its underlying mechanism.Method: Canagliflozin (30 mg/kg/day) was administered by gavage to streptozotocin-induced diabetic apolipoprotein E-deficient (ApoE−/−) mice. Sudan IV staining was performed at the aortic arch. Immunostaining, quantitative RT-PCR, and vascular reactivity assay were performed using the aorta. In vitro experiments using human umbilical vein endothelial cells (HUVECs) were also performed.Result: Canagliflozin decreased blood glucose (P < 0.001) and total cholesterol (P < 0.05) levels. Sudan IV staining showed that 12-week canagliflozin treatment decreased atherosclerotic lesions (P < 0.05). Further, 8-week canagliflozin treatment ameliorated endothelial dysfunction, as determined by acetylcholine-induced vasodilation (P < 0.05), and significantly reduced the expressions of inflammatory molecules such as ICAM-1 and VCAM-1 in the aorta at the RNA and protein levels. Canagliflozin also reduced the expressions of NADPH oxidase subunits such as NOX2 and p22phox in the aorta and reduced urinary excretion of 8-OHdG, suggesting a reduction in oxidative stress. Methylglyoxal, a precursor of advanced glycation end products, increased the expressions of ICAM-1 and p22phox in HUVECs (P < 0.05, both). Methylglyoxal also decreased the phosphorylation of eNOSSer1177 and Akt but increased the phosphorylation of eNOSThr495 and p38 MAPK in HUVECs.Conclusion: Canagliflozin prevents endothelial dysfunction and atherogenesis in diabetic ApoE−/− mice. Anti-inflammatory and antioxidative potential due to reduced glucose toxicity to endothelial cells might be its underlying mechanisms.  相似文献   
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A female who had had no previous cerebrovascular events suffered a subarachnoid hemorrhage and was referred to our hospital. Angiography revealed an anterior communicating artery aneurysm and bilateral occlusion of the middle cerebral artery at its origin. She exhibited mild ischemic symptoms after clipping of the aneurysm, possibly as a consequence of disturbance of the collateral blood flow during surgery. This is the third such case reported in the literature.  相似文献   
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We report a patient with primary ulnar entrapment neuropathy in the midarm. Stimulation of multiple sites along the ulnar nerve showed a motor conduction block at a distance of 7.5–10 cm proximal to the medial epicondyle, where the nerve was compressed by the medial intermuscular septum. Anatomically, the possibility of ulnar nerve entrapment in this segment has long been suggested, and stimulation at least 10 cm above the medial epicondyle may reveal the entrapment. Muscle Nerve 39: 707–710, 2009  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Previous studies examined the right atrial (RA) input site of the antegrade fast pathway (AFp) (AFpI). However, the left atrial (LA) input to...  相似文献   
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A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials.  相似文献   
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The molecular species composition of alpha-mycolic acids ranging from C68 to C86 in 13 rapidly growing and 12 slowly growing mycobacterial species was determined by gas chromatography, gas chromatography-mass spectrometry, and mass chromatography. In gas chromatographic analysis, the molecular species of alpha-mycolic acids were well separated as trimethylsilyl ether derivatives of the methyl esters, according to their total carbon numbers. The total carbon and double-bond numbers of mycolic acids at each peak on gas chromatograms were determined from the [M]+, [M - 15]+, and [M - 90]+ ions on the mass spectrum, and straight and branched chain structures were identified by the mass fragment ions [A]+, due to C2--C3 cleavage [R-CH-O-Si(CH3)3]+, and [B]+, due to C3--C4 cleavage [(CH3)3-Si-O-CH-CH(R')-COOCH3]+. The concentration of odd- and even-carbon-numbered mycolic acids, which often overlap each other on gas chromatograms, and the composition of three homologous mycolic acids with different alpha units (C22:0, C24:0, and C26:0) were clearly determined by mass chromatography monitoring [M - 15]+ ions and [B - 29]+ ions, respectively. The molecular species composition of alpha-mycolic acids and their average carbon numbers (av. cn.) as a simple expression of the composition were calculated from the mass chromatograms. Each mycobacterial species examined was demonstrated to possess a characteristic profile of alpha-mycolic acid composition, and based on this the species were classified approximately into eight groups: C68 to C76 (av. cn. 72), dienoic, possessing a C20 alkyl branch at the 2 position (C22 alpha-unit) for Mycobacterium diernhoferi and Mycobacterium sp. strain 3707, a chromogenic rapid grower; C72 to C78 (av. cn. 75), dienoic with both C22 and C24 alpha units, containing a small or a large amount of odd-carbon-numbered molecules, for M. vaccae, M. rhodesiae, and M. phlei (chromogenic rapid growers); C72 to C80 (av. cn. 75 to 77), dienoic with C24 alpha-unit, containing a moderate or a large amount of odd-carbon-numbered molecules, for M. smegmatis, M. chitae, M. chelonae (M. chelonei), and M. fortuitum (nonchromogenic rapid growers); C78 to C82 (av. cn. 80), even-carbon-numbered dienoic with C24 alpha unit for M. agri and M. thermoresistible (rapid growers); C75 to C81 (av. cn. 77 to 79), odd-carbon-numbered dienoic with C24 alpha unit for M. nonchromogenicum complex (M. nonchromogenicum, M. terrae, and "M. novum") (slow growers); (vi) C76 to C84 (av. cn. 79 to 81), even-carbon-numbered dienoic with C24 alpha unit for MAIS complex including M. scrofulaceum, M. avium, and M. intracellulare (slow growers); (vii) C72 to C80 (av. cn. 77 to 79), even-carbon-numbered dienoic with C24 alpha unit for M. szulgai, M. gordonae, and M. kansasii (chromogenic slow growers); and (viii) C76 to C86 (av. cn. 79 to 81), even-carbon-numbered dienoic with C26 alpha unit M. bovis Ravenol and BCG and M. tuberculosis H37Rv. This study demonstrated that gas chromatography-mass spectrometric analysis of the molecular species composition of alpha-mycolic acid can give rapid, important, and very precise information for the identification of pathogenic and nonpathogenic mycobacterial species.  相似文献   
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