Oxidative stress increases Fas ligand expression in endothelial cells

BACKGROUND: Fas ligand (FasL) induces apoptosis in Fas-bearing target cells, such as leukocytes, and up-regulation of FasL expression on the endothelium may contribute to anti-inflammatory reactions that attenuate leukocyte extravasation during inflammation. Since oxidants generated during inflammation and cigarette smoking may modulate endothelial function, we examined the effect of H(2)O(2 )and cigarette smoke on endothelial FasL expression. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to nontoxic concentrations of H(2)O(2 )and cigarette smoke extracts (CSE). Membrane FasL expression was assessed by immunostaining with anti-FasL antibody followed by either monolayer-cell-based spectrofluorimetry or flow cytometry. Soluble FasL in culture supernatants was measured by enzyme-linked immunosorbent assay. For the cytotoxic assay, HUVECs were exposed to H(2)O(2 )and co-cultured with neutrophils. Neutrophils were stained by a peroxidase/diaminobenzidine-based reaction, and apoptosis was evaluated on the basis of nuclear morphology after Giemsa staining. To analyze in vitro FasL expression in arteries, rat thoracic aortas were incubated with H(2)O(2), and paraffin-embedded sections were prepared for immunohistochemistry with anti-FasL antibody. RESULTS: Exposure of HUVECs to H(2)O(2 )dose-dependently increased their levels of both membrane and soluble forms of FasL expression. CSE exposure also caused increased levels of FasL expression, but the increase was partially inhibited by the addition of catalase. When co-cultured with neutrophils, HUVECs exposed to H(2)O(2 )significantly promoted neutrophil apoptosis. Rat thoracic aortas incubated with H(2)O(2 )exhibited increased FasL expression on their endothelium. CONCLUSION: Low levels of oxidative stress increase FasL expression on endothelial cells, thereby potentially reducing leukocyte extravasation and tissue damage

Des-gamma-carboxy Prothrombinは肝細胞癌のAutologousな増殖因子である

Des-gamma-carboxyl prothrombin (DCP) is a well recognized tumor marker for hepatocellular carcinoma (HCC). In the present study, we demonstrate that DCP has a mitogenic effect on HCC cell lines. Purified DCP stimulated DNA synthesis of Hep3B and SK-Hep-1 cells in a dose-dependent manner. DCP was found to bind with cell surface receptor Met causing Met autophosphorylation and also to activate STAT3 signaling pathway through Janus kinase 1. Luciferase gene reporter analysis showed that DCP induced STAT3-related transcription. Small interfering RNAs against both STAT3 and Met abrogated DCP-induced cell proliferation. DCP did not affect the mitogen-activated protein kinase pathway, Myc signaling pathway, or phosphoinositide 3-kinase/Akt pathway. Based on these results, we believe that DCP acts as an autologous mitogen for HCC cell lines. The Met-Janus kinase 1-STAT3 signaling pathway may be a major signaling pathway for DCP-induced cell proliferation

Causal Model of Work Engagement among Registered Nurses and Licensed Practical Nurses Working in Long-Term Care Contexts in Japan

The objective of this study was to determine a causal process underlying work engagement, in which individual resources (i.e., resilience) and job resources influence work performance, mediated by work engagement in different types of nurses working in long-term care contexts. We investigated a work engagement causal model in which individual and job resources were set as antecedent factors, work engagement as a mediating factor, and work performance as the outcome, to clarify differences between registered nurses (RNs) and licensed practical nurses (LPNs) working in long-term care contexts. We conducted a questionnaire-based survey with 1,786 Japanese nurses working in long-term care contexts in the Tohoku region. Using 1,269 respondents, we examined the causal model using structural equation modeling (SEM) and multiple population analysis to compare between RNs and LPNs. The results revealed a process whereby individual and job resources influenced work performance, mediated by work engagement, in RNs. In other words, greater individual and job resources enhance pride in work and positive emotion (i.e., work engagement), and greater positive emotion improves work performance. This process was not equivalent in LPNs. In LPNs, the most significant factor affecting work performance was the direct effect of job resources; moreover, the mediating effect of work engagement was not supported. The results demonstrated that in order to improve performance among LPNs working in long-term care contexts, it is important to provide job resource support, as well as to facilitate positive emotion through pride in one’s work

Radiotherapy for inoperable and refractory endometriosis presenting with massive hemorrhage: a case report

INTRODUCTION: Many patients with endometriosis are treated with medication or by surgical approaches. However, a small number of patients do not respond to medication and are inoperable because of comorbidities. This case report shows the effectiveness of radiotherapy for refractory endometriosis and includes a time series of serum estradiol levels. CASE PRESENTATION: A 47-year-old Asian woman presented to our facility with uncontrolled endometriosis refractory to medication. Our patient was considered inoperable because of severe idiopathic thrombocytopenic purpura, and underwent radiotherapy for massive genital bleeding requiring blood transfusions. A radiation dose of 20Gy in 10 fractions was delivered to the pelvis, including the bilateral ovaries, uterus, and myomas. An additional 10Gy in five fractions was delivered to the endometrium to control residual bleeding. Genital bleeding was completely inhibited on day 46 after radiotherapy. Hormonal analysis revealed that radiotherapy induced post-menopausal status. Two years after radiotherapy, atypical genital bleeding had not recurred and has been well controlled without side effects. CONCLUSIONS: Disrupted ovarian function is an adverse effect of radiotherapy. However, radiotherapy can be useful for inducing menopause. In cases of medication-refractory or inoperable endometriosis, radiotherapy would be an effective treatment option

Inhibitory action of a macrolide antibiotic, roxithromycin, on co-stimulatory molecule expressions in vitro and in vivo.

OBJECTIVE: The influence of a macrolide antibiotic, roxithromycin (RXM), on co-stimulatory molecule expression was examined in vitro and in vivo. MATERIALS AND METHODS: Spleen cells obtained from BALB/c mice 10 days after immunization with 8.0 microg of hemocyanin absorbed to 4.0 mg of aluminum hydroxide were cultured in the presence of 100.0 microg/ml of hemocyanin and various concentrations of RXM. We first examined the influence of RXM on cell activation by examining the proliferative response of cells and cytokine production. We also examined the influence of RXM on co-stimulatory molecule (CD40, CD80 and CD86) expressions on cultured splenic B-lymphocytes induced by in vitro antigenic stimulation using flow cytometry. In the second part of experiments, non-immunized and immunized mice were treated orally with 2.5 mg/kg of RXM once a day for 4 or 8 weeks. Splenic B lymphocytes were obtained from these mice 24 h after antigenic challenge, and co-stimulatory molecule expressions were examined by flow cytometer. RESULTS: Cell activation induced by in vitro antigenic stimulation was suppressed by RXM when cells were cultured in the presence of more than 5.0 microg/ml of the agent. Addition of RXM at a concentration of 5.0 microg/ml into cell cultures also suppressed co-stimulatory molecule (CD40, CD80 and CD86) expressions on splenic B lymphocytes, which was enhanced by antigenic stimulation in vitro. Oral RXM administration for 4 weeks clearly suppressed the enhancement of CD40 and CD86 (but not CD80) expressions on splenic B lymphocytes induced by antigenic stimulation in vivo. This suppressive activity of RXM on co-stimulatory molecule (CD40 and CD86) expressions was further strengthened by the treatment of mice for 8 weeks. Long-term treatment with oral RXM also suppressed CD80 expressions, which was not suppressed by 4-week treatment. CONCLUSION: The present results suggest that RXM exerts its immunomodulating effects through suppression of both cell activation and co-stimulatory molecule expressions induced by antigenic stimulation. These suppressive activities of RXM might contribute, in part, to the therapeutic mode of action of RXM on inflammatory diseases

Optimization of Light-Inducible Gal4/UAS Gene Expression System in Mammalian Cells

遺伝子発現を光で制御できる新技術を開発 --発生・幹細胞研究への貢献に期待--. 京都大学プレスリリース. 2020-08-28.Light-inducible gene expression systems represent powerful methods for studying the functional roles of dynamic gene expression. Here, we developed an optimized light-inducible Gal4/UAS gene expression system for mammalian cells. We designed photoactivatable (PA)-Gal4 transcriptional activators based on the concept of split transcription factors, in which light-dependent interactions between Cry2-CIB1 PA-protein interaction modules can reconstitute a split Gal4 DNA-binding domain and p65 transcription activation domain. We developed a set of PA-Gal4 transcriptional activators (PA-Gal4cc), which differ in terms of induced gene expression levels following pulsed or prolonged light exposure, and which have different activation/deactivation kinetics. These systems offer optogenetic tools for the precise manipulation of gene expression at fine spatiotemporal resolution in mammalian cells

An Analysis of Factors that Exacerbate Asthma, Based on a Japanese Questionnaire

ABSTRACTBackgroundIt is known that a wide variety of factors exacerbate asthma; however, few studies have investigated the factors that exacerbate asthma from a patient's perspective. The aim of this study was to analyze the factors that exacerbate asthma, based on a questionnaire completed by asthma patients in Niigata Prefecture.MethodsBased on questionnaires given to 3085 patients who visited the medical institutes in the Niigata Prefecture monthly from September through October 2006, groups stratified by sex, age, disease type and disease severity, were analyzed for factors contributing to asthma exacerbation, as described in the guideline of the Japanese Society of Allergology.ResultsThe leading exacerbating factor chosen by patients was a change in the weather, followed by smoking, allergen exposure, fatigue, stimulants, and air pollutants. Respiratory infection, widely recognized as a critical factor of severe exacerbation, was ranked seventh. Allergen exposure and air pollutants were prominent in younger individuals, whereas respiratory infection tended to be more common in elderly subjects. Allergen exposure, air pollutants, and exercise were significantly more common in atopic-type patients, in contrast with respiratory infection in non-atopic-type patients. According to multiple regression analysis, poor asthma control during the last one year was associated with changes in the weather, whereas the non-atopic disease type was related to exacerbation by respiratory infection. Current smoking was associated with both factors.ConclusionsMany factors exacerbate asthma, depending on the individual case and his/her background. These data suggest that changes in the weather may be more important factor for patients in asthma exacerbation

Effects of red pepper on appetite and energy intake

Two studies were conducted to investigate the effects of red pepper (capsaicin) on feeding behaviour and energy intake. In the first study, the effects of dietary red pepper added to high-fat (HF) and high-carbohydrate (HC) meals on subsequent energy and macronutrient intakes were examined in thirteen Japanese female subjects. After the ingestion of a standardized dinner on the previous evening, the subjects ate an experimental breakfast (1883 kJ) of one of the following four types: (1) HF; (2) HF and red pepper (10 g); (3) HC; (4) HC and red pepper. Ad libitum energy and macronutrient intakes were measured at lunch-time. The HC breakfast significantly reduced the desire to eat and hunger after breakfast. The addition of red pepper to the HC breakfast also significantly decreased the desire to eat and hunger before lunch. Differences in diet composition at breakfast time did not affect energy and macronutrient intakes at lunch-time. However, the addition of red pepper to the breakfast significantly decreased protein and fat intakes at lunch-time. In Study 2, the effects of a red-pepper appetizer on subsequent energy and macronutrient intakes were examined in ten Caucasian male subjects. After ingesting a standardized breakfast, the subjects took an experimental appetizer (644 kJ) at lunch-time of one of the following two types: (1) mixed diet and appetizer; (2) mixed diet and red-pepper (6 g) appetizer. The addition of red pepper to the appetizer significantly reduced the cumulative ad libitum energy and carbohydrate intakes during the rest of the lunch and in the snack served several hours later. Moreover, the power spectral analysis of heart rate revealed that this effect of red pepper was associated with an increase in the ratio sympathetic: parasympathetic nervous system activity. These results indicate that the ingestion of red pepper decreases appetite and subsequent protein and fat intakes in Japanese females and energy intake in Caucasian males. Moreover, this effect might be related to an increase in sympathetic nervous system activity in Caucasian males

Association between the quality of life and asymptomatic episodes of paroxysmal atrial fibrillation in the J-RHYTHM II study

AbstractBackgroundParoxysmal atrial fibrillation (AF) patients have a reduced quality-of-life (QoL) despite the fact that the majority of AF episodes are asymptomatic. Asymptomatic AF is likely to be associated with substantial morbidity and mortality rates similar to those with symptomatic AF, whereas its effect on the QoL has not yet been clarified.PurposeWe studied the specific contribution of asymptomatic AF episodes to reducing the QoL.MethodsWe assessed the QoL in 233 patients with paroxysmal AF and hypertension (age 64.9±9.7 years, 71% male) enrolled in the Japanese Rhythm Management Trial II for Atrial Fibrillation (J-RHYTHM II study) using an AF-specific QoL questionnaire (AFQLQ). The AFQLQ comprised 3 components: AFQLQ1, the frequency and duration of symptoms; AFQLQ2, severity of symptoms; and AFQLQ3, limitations in daily activities and mental anxiety. Higher scores indicated a better QoL. Each patient transmitted electrocardiograms for 30s daily at a predetermined time as well as whenever arrhythmia-related symptoms were experienced. We examined the relationship between the 3 AFQLQ components and frequency of symptomatic and asymptomatic AF episodes (days/month) during 12 months of follow-up.ResultsThe symptomatic and asymptomatic AF frequencies were 0.9±3.1 days/month and 1.5±3.5 days/month, respectively. AFQLQ1 negatively correlated with the symptomatic AF frequency (Spearman's correlation coefficient: r=−0.332, p<0.001). AFQLQ2 and AFQLQ3 correlated with both the symptomatic AF frequency (r=−0.27, p<0.001 and r=−0.265, p<0.001, respectively) and asymptomatic AF frequency (r=−0.197, p<0.01 and r=−0.229, p<0.005, respectively).ConclusionThe asymptomatic AF episode frequency correlates with a reduced QoL in patients with paroxysmal AF, suggesting that there would be psychological benefits to its reduction

Enhancement of Vivid-based photo-activatable Gal4 transcription factor in mammalian cells

The Gal4/UAS system is a versatile tool to manipulate exogenous gene expression of cells spatially and temporally in many model organisms. Many variations of light-controllable Gal4/UAS system are now available, following the development of photo-activatable (PA) molecular switches and integration of these tools. However, many PA-Gal4 transcription factors have undesired background transcription activities even in dark conditions, and this severely attenuates reliable light-controlled gene expression. Therefore, it is important to develop reliable PA-Gal4 transcription factors with robust light-induced gene expression and limited background activity. By optimization of synthetic PA-Gal4 transcription factors, we have validated configurations of Gal4 DNA biding domain, transcription activation domain and blue light-dependent dimer formation molecule Vivid (VVD), and applied types of transcription activation domains to develop a new PA-Gal4 transcription factor we have named eGAV (enhanced Gal4-VVD transcription factor). Background activity of eGAV in dark conditions was significantly lower than that of hGAVPO, a commonly used PA-Gal4 transcription factor, and maximum light-induced gene expression levels were also improved. Light-controlled gene expression was verified in cultured HEK293T cells with plasmid-transient transfections, and in mouse EpH4 cells with lentivirus vector-mediated transduction. Furthermore, light-controlled eGAV-mediated transcription was confirmed in transfected neural stem cells and progenitors in developing and adult mouse brain and chick spinal cord, and in adult mouse hepatocytes, demonstrating that eGAV can be applied to a wide range of experimental systems and model organisms