rho-mediated protein tyrosine phosphorylation in lysophosphatidic-acid-induced tumor-cell invasion

Rat ascites hepatoma cells (MMI) invade a mesothelial cell monolayer in vitro in assay medium containing serum, but not in serum-free medium. Serum could be completely replaced by I-oleoyl lysophosphatidic acid (LPA) in inducing invasion. LPA-induced invasion was inhibited by genistein, a tyrosine-kinase inhibitor. Protein tyrosine phosphorylation in response to LPA was thus analyzed in order to determine the molecular mechanism of invasion. LPA of invasion-inducible concentrations evoked a transient increase in tyrosine phosphorylation, mainly of 110- to 130-kDa proteins in MMI cells but not in mesothelial cells. These concentrations of LPA were over 10 times higher (10 to 25 μM) than those necessary to produce a variety of biological actions, such as tyrosine phosphorylation in fibroblasts, neurite retraction and platelet aggregation. Protein tyrosine phosphorylation and invasion by MMI cells induced by LPA are largely regulated by rho p21, because both were inhibited by Clostridium botulinum C3 exo-enzyme, which is known to specifically inactivate rho p21. Invasion of MCL by MMI cells induced by serum and that by B16FE7 cells induced by LPA were inhibited by genistein or C3 as well. By immunoprecipitation, we detected p125 focal adhesion kinase (FAK) as a major protein of 110- to 130-kDa tyrosine phosphorylated in response to LPA. Tyrosine phosphorylation of paxillin by LPA was also detected. © 1996 Wiley-Liss, Inc.     

阿尔茨海默病和额颞叶痴呆徘徊行为的比较

目的 比较阿尔茨海默病和额颞叶痴呆徘徊者步行活动水平及活动节律的差异.方法 利用电子示踪监测系统对阿尔茨海默病(Alzheimer disease,AD)徘徊者27例及额颞叶痴呆(frontotemporal dementia,FTD)徘徊者7例进行连续30 d的24 h活动监测,比较两组日、夜活动水平(步行距离),以及活动节律的日间稳定性和日内变异性.结果 AD组和FTD组的年龄分别为 (73.89 ± 9.12)岁和(63.43 ± 14.93)岁,而发病年龄分别为 (70.16 ± 9.26)岁、(58.17 ± 15.16)岁.AD组的年龄较大而发病年龄较晚(P ＜ 0.05).AD组和FTD组在6:00 ～ 23:59的步行距离分别为(2119.39 ± 2535.59)m、(4842.44 ± 2617.94)m,后者较长(P ＜ 0.05),但两组在0:00 ～ 5:59的活动水平差异无统计学意义(P ＞ 0.05).FTD组活动节律更加稳定[(0.50 ± 0.11) vs (0.29 ± 0.15),P ＜ 0.01],日内活动变异片段数更少[(2.80 ± 0.74) vs (4.07 ± 0.95),P ＜ 0.01].结论 AD 和FTD 两类痴呆的徘徊行为特点不同,提示有必要建立痴呆亚型特异性徘徊行为的非药物干预策略.     

Semi-quantitative immunohistochemical studies on Thy-1 antigen expressed by thymic myoid cells

Thy-1 antigen expression in the rat thymic myoid cell line R615B2 (Thy-1(+] and R613Ad (Thy-1(-] was studied with a semi-quantitative immunohistochemical assay without disrupting the cell cultures. With this assay, the quantity of Thy-1 antigen on R615B2 cells was detected separately in the cytoplasm and on the cell surface by the use of appropriate fixatives such as chilled ethanol and methanol + 0.3% H2O2. Extracellular Thy-1 antigen was also found in the culture supernatant of R615B2 cells. More than half of extracellular Thy-1 antigen remained in the supernatant even after 100,000 X g centrifugation. No form of Thy-1 antigen was detected at significant levels in R613Ad cells.     

Lung resection affects the postoperative arrhythmia and electrocardiographic axis deviation]

After lung lobectomy or pneumonectomy, the mediastinal shift and diaphragmatic elevation are occurred. Because this phenomenon may affect the heart positional change, we studied the electrocardiographic QRS axis in the frontal plane (from leads I and III) and the postoperative arrhythmia. Seventy three patients who had no heart disease including arrhythmia before the surgery were recorded their electrocardiogram (ECG) before their surgery and after their discharge. When the postoperative ECG was recorded, they had no respiratory failure nor cancer recurrence, and their lungs were fully expanded in their thoracic cages. After right upper lobectomy (19 cases), the axis was twisted rightward slightly (2.1 degrees). Right middle lobectomy (2 cases, 9.5 degrees) and right upper and middle lobectomies (3 cases, 7.3 degrees) twisted the heart axes more rightwards. Right lower lobectomy (12 cases, -1.0 degree) and right middle and lower lobectomies (3 cases, -17.7 degrees) contorted their axes leftwards and right pneumonectomy (5 cases, 31.4 degrees) rightwards. The axes were turned rightwards after the left upper lobectomy (18 cases, 2.8 degrees) and the left lower lobectomy (7 cases, 3.9 degrees). Left pneumonectomy (4 cases, -4.0 degrees) twisted the axis leftwards. After the surgery, arrhythmias were recorded in 14 cases and, among these patients, 5 cases were required the oral anti-arrhythmic medication. Most of these cases changed their heart axes after the surgery and it is suggested that the axial deviation may contribute to their postoperative arrhythmia.     

The Inverse Correlation of Isoflavone Dietary Intake and Headache in Peri- and Post-Menopausal Women

This study investigated the relationship between headache and dietary consumption of a variety of nutrients in middle-aged women. This cross-sectional analysis used first-visit records of 405 women aged 40–59 years. The frequency of headaches was assessed using the Menopausal Health-Related Quality of Life Questionnaire. Of the 43 major nutrient intakes surveyed using the brief-type self-administered diet history questionnaire, those that were not shared between women with and without frequent headaches were selected. Multiple logistic regression analysis was used to identify nutrients independently associated with frequent headaches. After adjusting for background factors related to frequent headache (vasomotor, insomnia, anxiety, and depression symptoms), the estimated dietary intake of isoflavones (daidzein + genistein) (mg/1000 kcal/day) was negatively associated with frequent headaches (adjusted odds, 0.974; 95% confidence interval, 0.950–0.999). Moreover, the estimated isoflavone intake was not significantly associated with headache frequency in the premenopausal group, whereas it significantly correlated with that in the peri- and post-menopausal groups. Headache in peri- and post-menopausal women was inversely correlated with the dietary intake of isoflavones. Diets rich in isoflavones may improve headaches in middle-aged women.     

Pharmacoepidemiologic investigation of a clonazepam-valproic acid interaction by mixed effect modeling using routine clinical pharmacokinetic data in Japanese patients

Non-linear Mixed Effects Modeling (NONMEM) was used to estimate the effects of clonazepam-valproic acid interaction on clearance values using 576 serum levels collected from 317 pediatric and adult epileptic patients (age range, 0.3-32.6 years) during their clinical routine care. Patients received the administration of clonazepam and/or valproic acid. The final model describing clonazepam clearance was CL = 144.0 TBW-0.172 1.14VPA, where CL is total body clearance (mL/kg/h); TBW is total body weight (kg); VPA = 1 for concomitant administration of valproic acid and VPA = zero otherwise. The final model describing valproic acid clearance was CL (mL/kg/h) = 17.2 TBW-0.264 DOSE0.159 0.821CZP 0.896GEN, where DOSE is the daily dose of valproic acid (mg/kg/day); CZP = 1 for concomitant administration of clonazepam and CZP = zero otherwise; GEN = 1 for female and GEN = zero otherwise. Concomitant administration of clonazepam and valproic acid resulted in a 14% increase in clonazepam clearance, and a 17.9% decrease in valproic acid clearance.     

Prevalence of Burnout among Internal Medicine and Primary Care Physicians before and during the COVID-19 Pandemic in Japan

Objective To evaluate the change in the prevalence of burnout during the COVID-19 pandemic among internists and primary care physicians in Japan, and to identify factors associated with the exacerbation of burnout among these populations during this period. Methods This was a cross-sectional study based on two web-based surveys conducted in January 2020 (before the declaration of the COVID-19 pandemic) and June 2020 (during the pandemic). The participants were internists and primary care physicians of the Japanese Chapter of the American College of Physicians. The main outcome was the change in the prevalence of burnout between before and during the “first wave” of the pandemic. We also examined factors associated with the exacerbation of burnout during this period. Results Among the 283 respondents in the first survey and 322 in the second survey, 98 (34.6%) and 111 (34.5%) reported symptoms of burnout, respectively. In June 2020, 82 respondents (25.5%) reported that their level of burnout exacerbated compared to January 2020. Only the experience of self-quarantine was associated with the exacerbation of burnout [odds ratio (OR) 3.12; 95% confidence interval (CI) 1.49-6.50; p=0.002], while being a woman, being a resident physician, and an experience of having worked in a prefecture under a state of emergency were not. Conclusions No marked change in the prevalence of burnout among internists and primary care physicians in Japan was observed during the COVID-19 pandemic as a whole. However, self-quarantine was associated with the exacerbation of the burnout level.