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101.
BackgroundThis pilot study aimed to investigate the current status of e‐cigarettes (ECs) use patterns among patients with chronic airway disease or chronic respiratory symptoms and the effects of ECs use on respiratory and mental health.MethodsA cross‐sectional survey was conducted at the outpatient clinic of eight teaching hospitals in South Korea between November 2019 and December 2019. All adult ECs users (19 years and above) who visited the outpatient clinic as a patient with chronic airway disease or chronic respiratory symptoms were eligible to participate in this study.ResultsA total of 51 subjects responded to the survey. Most of the participants were male (92.2%) and the mean age was 41.8 years. Dominant airway diseases were asthma and chronic obstructive pulmonary disease. Most of the subjects had a history of cigarette smoking, and 19 subjects were dual users of current cigarettes and ECs. Most of the subjects started ECs use due to health‐related reasons. When comparing exclusive ECs users and dual users, St. George''s respiratory questionnaire (SGRQ) scores, the proportion of cases with moderate to severe depressive symptoms, and average Fagerstrom test for nicotine dependence scores for ECs were higher in dual users than exclusive ECs users (mean 4.64 vs. 2.38, p = 0.006), respectively.ConclusionMost of the subjects started ECs use due to health concerns, but dual users have more respiratory symptoms and higher nicotine dependence in this pilot study. One hypothesis that comes from these results is that greater nicotine dependence may influence behaviours, habits, and views about ECs. These preliminary observations need confirmation in a large cohort.  相似文献   
102.
BackgroundThis study aimed to examine the prognostic significance of sarcopenia combined with systemic inflammation in patients who underwent curative hepatectomy for hepatocellular carcinoma (HCC).MethodsBetween January 2010 and July 2019, we identified 159 patients with HCC who underwent curative hepatectomy at three institutional centers. We retrospectively analyzed clinicopathological outcomes, surgical outcomes, platelet lymphocyte ratio (PLR) as a systemic inflammatory marker, and computed tomography (CT)-assessed sarcopenia at the third lumbar vertebra level (L3).ResultsSarcopenia was noted in 74 (46.5%) of 159 patients and was significantly associated with male sex, low body mass index (BMI), and high PLR. In the multivariate analysis, sarcopenia [hazard ratio (HR): 2.127, P=0.026] and high PLR (HR: 1.971, P=0.038) were associated with a decrease in overall survival (OS) but not in recurrence-free survival (RFS). The combination of sarcopenia and PLR status stratified the 5-year OS into 82.0% (non-sarcopenia and a low PLR), 68.3% (sarcopenia or a high PLR), and 44.4% (sarcopenia and a high PLR) (P=0.001). In the multivariate analysis, “sarcopenia and a high PLR” and “sarcopenia or a high PLR” were revealed to be significant predictors of OS (HR: 4.300, P=0.001 and HR: 2.723, P=0.010, respectively).ConclusionsSarcopenia and high PLR were significantly associated with poor OS. The combination of these two factors may be useful for predicting survival of patients with HCC undergoing curative hepatectomy.  相似文献   
103.
Type 1 diabetes (T1D) is caused by dysregulation of the immune system in the pancreatic islets, which eventually leads to insulin-producing pancreatic β-cell death and destabilization of glucose homeostasis. One of the major characteristics of T1D pathogenesis is the production of inflammatory mediators by macrophages that result in destruction or damage of pancreatic β-cells. In this study the inflammatory microenvironment of T1D was simulated with RAW264.7 cells and MIN6 cells, acting as macrophages and pancreatic β-cells respectably. In this setting, peroxiredoxin-1, an anti-oxidant enzyme was knocked down to observe its functions in the pathogenesis of T1D. RAW264.7 cells were primed with lipopolysaccharide and co-cultured with MIN6 cells while PRX-1 was knocked down in one or both cell types. Our results suggest that hindrance of PRX-1 activity or the deficiency of this enzyme in inflammatory conditions negatively affects pancreatic β-cell survival. The observed decrease in viability of MIN6 cells seems to be caused by nitric oxide production. Additionally, it seems that PRX-1 affects previously reported protective activity of IL-6 in pancreatic β cells as well. These results signify new, undiscovered roles for PRX-1 in inflammatory conditions and may contribute toward our understanding of autoimmunity.  相似文献   
104.
Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.  相似文献   
105.
The aim of this study was to assess the expression of significant components of autophagy including beclin-1, light chain (LC) 3A, LC3B, and p62 in the molecular subtypes of triple-negative breast cancer (TNBC) and to evaluate the implications of the results. Tissues from 119 cases of TNBC were used for a tissue microarray. Expression of cytokeratin (CK) 5/6, epidermal growth factor receptor (EGFR), claudin 3, claudin 4, claudin7, E-cadherin, androgen receptor (AR), and gamma-glutamyltransferase 1 (GGT-1) was detected by immunohistochemical staining of the tissue microarrays. According to the results, the 119 cases of TNBC were subclassified into basal-like type (CK5/6-positive and/or EGFR-positive group), molecular apocrine type (AR-positive and/or GGT-1-positive group), claudin low type (claudin 3-, claudin 4-, or claudin 7-negative and/or E-cadherin-negative group), mixed type (having the features of more than two types), or null type (none of the above). Immunohistochemical staining for autophagy-related markers including beclin-1, LC3A, LC3B, and p62 was performed to evaluate the difference between clinicopathological parameters. TNBCs were categorized as basal-like type (36 patients, 30.3?%), molecular apocrine type (8 patients, 6.7?%), claudin low type (16 patients, 13.4?%), mixed type (37 patients, 31.1?%), and null type (22 patients, 18.5?%). Expression of nuclear p62 was higher in the molecular apocrine type and claudin low type than in other types of TNBC (p?=?0.008). Expression of beclin-1 was higher in molecular apocrine type than in other TNBC types (p?=?0.039). Expression of LC3A and LC3B showed no difference between the molecular subtypes. Multivariate Cox analysis revealed that the negative expression of p62 was associated with shorter disease-free survival [p?=?0.012; odds ratio, 3.192; 95?% confidence interval (CI), 1.293?C7.882] and shorter overall survival (p?=?0.009; odds ratio, 3.895; 95?% CI, 1.409?C10.771). Among the subtypes of TNBC, molecular apocrine breast cancer showed a higher expression of nuclear p62 and beclin-1 than others, which reflected higher autophagy activity.  相似文献   
106.
Parkinson??s disease (PD) is a progressive degenerative disorder of the central nervous system. Levodopa (L-dopa), dopamine precursor is the most effective therapeutic drug for PD patients. Levodopa (LDP) and its three metabolites in rat plasma were determined using high performance liquid chromatography coupled with tandem mass spectrometry (LC?CMS/MS). Method validation was conducted in terms of linearity, accuracy, precision, recovery, specificity, limit of detection, limit of quantification and stability. Correlation coefficients (r 2) were above 0.9965. The intra-day accuracy values at LLOQ (low limit of quantification), LQC (low quality control), MQC (medium quality control) and HQC (high quality control) levels were 85.7?C103.3, 96.5?C105.1, 90.7?C100.1 and 94.2?C101.3?%, respectively. The inter-day accuracy values at LLOQ, LQC, MQC and HQC levels were 77.6?C112.0, 91.1?C109.3, 84.3?C101.0 and 88.2?C103.9?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The recoveries (mean?±?%SD) for LLOQ, LQC, MQC and HQC were 82.7?±?3.7?C113?±?2.8?%, 86.6?±?5.7?C110.3±3.4?%, 90.9?±?3.6?C106?±?6.5 and 89.7?±?4.5?C97.4?±?6.7?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The validated LC?CMS/MS method was applied successfully to the measurement of LDP and its metabolites in the rat plasma samples.  相似文献   
107.
We investigated the effects of resveratrol on metastasis in in vitro and in vivo systems. 4T1 cells were cultured in the presence of various concentrations (0-30 µmol/L) of resveratrol. For experimental metastasis, BALB/c mice were injected intravenously with 4T1 cells in the tail vein, and were orally administered various concentrations (0, 100, or 200 mg/kg Body weight) of resveratrol for 21 days. After resveratrol treatment, cell adhesion, wound migration, invasion, and MMP-9 activity were significantly decreased in a dose-dependent manner in 4T1 cells (P < 0.05). The numbers of pulmonary nodules were significantly decreased in mice fed the resveratrol (P < 0.05). The plasma MMP-9 activity was decreased in response to treatment with resveratrol in mice (P < 0.05). We conclude that resveratrol inhibits cancer metastasis both in vitro and in vivo, and this inhibition is likely due to the decrease in MMP-9 activity caused by resveratrol.  相似文献   
108.
To promote the classification accuracy and decrease the time of extracting features and finding (near) optimal classification model of an ultrasound breast tumor image computer-aided diagnosis system, we propose an approach which simultaneously combines feature selection and parameter setting in this study.In our approach ultrasound breast tumors were segmented automatically by a level set method. The auto-covariance texture features and morphologic features were first extracted following the use of a genetic algorithm to detect significant features and determine the near-optimal parameters for the support vector machine (SVM) to identify the tumor as benign or malignant.The proposed CAD system can differentiate benign from malignant breast tumors with high accuracy and short feature extraction time. According to the experimental results, the accuracy of the proposed CAD system for classifying breast tumors is 95.24% and the computing time of the proposed system for calculating features of all breast tumor images is only 8% of that of a system without feature selection. Furthermore, the time of finding (near) optimal classification model is significantly than that of grid search. It is therefore clinically useful in reducing the number of biopsies of benign lesions and offers a second reading to assist inexperienced physicians in avoiding misdiagnosis.  相似文献   
109.
Sialadenosis is characterized by asymptomatic bilateral enlargement of the parotid glands. It is uncommon, especially in children. Diagnosis and analysis of sialadenosis based on imaging modalities have been rarely reported. Here, we report a case of sialadenosis in a child with leukemia, in which the diagnosis was made based on sonography and CT findings.  相似文献   
110.
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