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91.
Cardiac fibroblasts in culture produce factor(s) that induce hypertrophy of neonatal rat ventricular myocytes in vitro. As
in vivo, the myocyte hypertrophy response in culture is characterized by an increase in cell size and contractile protein
content, and by the activation of embryonic genes, including the gene for atrial natriuretic peptide. The purpose of this
study was to identify the factor(s) produced by fibroblasts that induce myocyte hypertrophy. The fibroblast hypertrophy activity
was inhibited using a combination of the endothelin A receptor blocker BQ-123 and an antibody to leukemia inhibitory factor.
The individual antagonists each caused a partial inhibition. The mRNAs for both leukemia inhibitory factor and endothelin
were detected by RT-PCR analysis and the concentration of both proteins was determined to be approximately 200 pmol/L in the
conditioned medium using immunoassays. Purified leukemia inhibitory factor and endothelin each induced distinctive morphological
changes in the myocytes. Their combination generated a different morphology similar to that induced by fibroblast conditioned
medium. Each factor also induced atrial natriuretic peptide production, but both were required for the myocytes to produce
the levels measured after exposure to fibroblast conditioned medium. These results show that hypertrophy activity produced
by cardiac fibroblasts in culture is a result of leukemia inhibitory factor and endothelin. 相似文献
92.
Hui Hua Chang Mei Hung Chi I Hui Lee Hsin Chun Tsai Po Wu Gean Yen Kuang Yang Ru-Band Lu Po See Chen 《Journal of affective disorders》2013
Background
A reciprocal relationship between diabetes risk and depression has been reported. There are few studies investigating glucose–insulin homeostasis before and after short-term antidepressant treatment in drug-naïve major depressive disorder (MDD) patients.Methods
This study included 104 healthy controls and 50 drug-naïve MDD patients diagnosed according to the DSM-IV criteria. These MDD patients were randomly assigned to receive fluoxetine or venlafaxine for six weeks. Depressive symptoms, body mass index, fasting plasma levels of glucose and insulin were measured.Results
Compared to the healthy controls, the fasting plasma insulin and the homeostasis model of assessment for pancreatic β-cell secretory function (HOMA-β) was significantly lower in the MDD patients before antidepressant treatment (7.7±4.8 μIU/mL vs. 5.1±4.2 μIU/mL, p=0.006; 114.2±72.3% vs. 74.8±52.0%, p=0.005, respectively). However, these indices were not correlated with depression severity. After 6 weeks of fluoxetine or venlafaxine treatment, the level of HOMA-β borderline significantly increased (108.1±75.5%, p=0.059).Limitations
The study was limited by the follow-up duration and lack of a placebo group.Conclusions
Antidepressants might affect insulin secretion independently of the therapeutic effects on MDD. Further studies are needed to investigate the long-term effects of antidepressants on insulin regulation in MDD patients. 相似文献93.
Chia-Cheng Tseng Chin-Chou Wang Huang-Chih Chang Tzu-Hsien Tsai Li-Teh Chang Kuo-Tung Huang Steve Leu Chia-Hung Yen Shih-Feng Liu Chih-Hung Chen Cheng-Ta Yang Hon-Kan Yip Meng-Chih Lin 《Disease markers》2013,35(5):301-310
Background. Endothelial-derived microparticles (EDMPs) and platelet-derived microparticles (PDMPs) have been reported to be increasing in various diseases including malignant diseases. Here, we investigated whether these MPs may be useful biomarkers for predicting lung cancer (LC) disease status, cell type, or metastasis. Methods and Results. One hundred and thirty LC patients were prospectively enrolled into the study between April 2011 and February 2012. Flow cytometric analysis demonstrated that the circulating levels of platelet-derived activated MPs (PDAc-MPs), platelet-derived apoptotic MPs (PDAp-MPs), endothelial-derived activated MPs (EDAc-MPs), and endothelial-derived apoptotic MPs (EDAp-MPs) were significantly higher in LC patients than in 30 age- and gender-matched normal control subjects (all P < 0.05). Additionally, circulating level of PDAc-MPs was significantly lower (P = 0.031), whereas the circulating levels of the other three biomarkers did not differ (all P > 0.1) in early stage versus late stage LC patients. Furthermore, the circulating levels of the four types of MPs did not differ among patients with different disease statuses (i.e., disease controlled, disease progression, and disease without treatment, i.e., fresh case) (all P > 0.2) or between patients with or without LC metastasis (all P > 0.5). Moreover, only the circulating level of EDAp-MPs was significantly associated with the different cell types (i.e., squamous cell carcinoma, adenocarcinoma, and small cell carcinoma) of LC (P = 0.045). Conclusion. Circulating MP levels are significantly increased in LC patients as compared with normal subjects. Among the MPs, only an increased level of EDAp-MPs was significantly associated with different LC cell types. 相似文献
94.
95.
96.
Ranawaka A. P. M. Perera Ronald Ko Owen T. Y. Tsang David S. C. Hui Mike Y. M. Kwan Christopher J. Brackman Esther M. W. To Hui-ling Yen Kathy Leung Samuel M. S. Cheng Kin Ho Chan Karl C. K. Chan Ka-Chi Li Linda Saif Vanessa R. Barrs Joseph T. Wu Thomas H. C. Sit Leo L. M. Poon Malik Peiris 《Journal of clinical microbiology》2021,59(2)
97.
Chia-Ter Chao Szu-Ying Lee Wei-Shun Yang Huei-Wen Chen Cheng-Chung Fang Chung-Jen Yen Chih-Kang Chiang Kuan-Yu Hung Jenq-Wen Huang 《International journal of medical sciences》2013,10(9):1092-1098
Introduction: Non-Pseudomonas gram-negative bacteria are responsible for an increasing proportion of cases of peritoneal dialysis (PD)-related peritonitis. The role of Citrobacter species in the etiology of PD-related peritonitis is often underestimated. In the present study, we aimed to describe the clinical features, laboratory findings, and short- and long-term outcomes in PD-related peritonitis caused by Citrobacter.Methods: A retrospective review of all episodes of PD-related peritonitis caused by Citrobacter from a single center between 1990 and 2010 was performed. Clinical features, microbiological data, and outcomes of these episodes were analyzed.Results: Citrobacter species was responsible for 11 PD-related episodes (1.8% of all peritonitis episodes) in 8 patients. Citrobacter freundii was the most common etiologic species (73%), and mixed growth was found in the other 3 episodes (27%). Approximately half (46%) of the episodes were associated with constipation and/or diarrhea. Of the Citrobacter isolates from all episodes, 54% were resistant to cefazolin, and only 18% were susceptible to cefmetazole. All isolates were susceptible to ceftazidime, cefepime, carbapenem, and aminoglycosides. More than half of the patients (54%) were hospitalized for index peritonitis, and 27% of the episodes involved a change in antibiotic medication. One patient had relapsing peritonitis caused by C. koseri (9%). The mortality rate of PD-related peritonitis caused by Citrobacter was 18%, and 89% of surviving patients developed technique failure requiring a modality switch after an average of 12 months of follow-up (range 1.2-31.2 months).Conclusion: PD-related peritonitis caused by Citrobacter is associated with poor outcomes, including high rates of antibiotic resistance, a high mortality rate, and a high rate of technique failure among survivors during the follow-up period. 相似文献
98.
Rob Mintenko David B. Kennedy Jolanta Aleksejuniene Alan G. Hannam Edwin H. Yen 《The Angle orthodontist》2020,90(2):187
Objectives:To determine changes in occlusal curves and dental tipping occurring from mandibular second premolar serial extraction, early extraction of deciduous mandibular second molars with missing second premolars, and late second premolar extraction compared with untreated controls.Materials and Methods:Information was collected from 85 subjects at three time points: T0, prior to serial extraction; T1, after serial extraction and drift prior to orthodontic treatment, and pretreatment for the late premolar extraction patients; and T2, posttreatment. Untreated age- and gender-matched controls were used for comparison. Three occlusal curves were measured on digitized mandibular casts, and dental tipping was assessed using lateral cephalograms.Results:At T0, there were no significant differences among groups. At T1, there was significant steepening of Monson''s sphere and the curve of Wilson between early and late extraction and control groups. At T2, the differences in Monson''s sphere and the curve of Wilson were fully corrected. At T1, there were significant differences in the tipping of mandibular 6''s, 4''s, and 3''s between the early extraction groups compared with the late extraction and control groups. At T2, these differences in tipping were fully corrected. There were no differences in mandibular incisor tipping between groups at T1 or T2.Conclusions:Serial extraction produced steeper occlusal curves and significant tipping of mandibular first molars, first premolars, and canines after extraction and physiologic drift (T1). Accentuated occlusal curves and tooth tipping were fully corrected following orthodontic treatment (T2). Mandibular incisor position was unchanged by serial or late second premolar extraction. 相似文献
99.