The homeostasis of microenvironment in central nervous system, essential for normal function, is maintained by blood-brain barrier (BBB). ZO-1 in tight junctions (TJs) plays an important role in maintaining BBB endothelial ion and solute barriers. Malfunction of BBB by reactive oxygen species has been attributed to disruption of TJs. This study examined H2 O2 effects on paracellular permeability and changes in TJ protein ZO-1 using primary culture of bovine brain microvessel endothelial cells. The BBB permeability,measured as TER, increased in a dose-and time-dependent manner when treated with H2O2 (0.01, 0.1, 1.0 mM). Cytotoxicity test revealed that H2O2 did not cause cell death below 1 mM H2 O2 within 4 hr. H2O2 caused intermittent disruption and loss of ZO-1 at tight junctions, but ZO-1 maintained steady state levels of expression. In conclusion, we report that H2O2 induces increased paracellular permeability of BBB that is accompanied with alterations in localization of ZO-1.
Blood-Brain Barrier ; Brain ; Cell Death ; Central Nervous System ; Endothelial Cells ; Homeostasis ; Microvessels ; Oxidative Stress* ; Permeability ; Reactive Oxygen Species ; Tight Junctions*

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by persistent airflow limitation. Therefore, both work ability and workday length may be affected in individuals with this disease. We studied a worker with suspected COPD and assessed fitness to work using post-bronchodilator spirometry, symptom assessment scales, and the exercise stress test. CASE REPORT: The patient was a 58-year-old man due to work as a field supervisor in the ship construction sector. He had a 40 pack-year smoking history and experienced occasional dyspnea when climbing stairs. He visited this hospital to receive cardiopulmonary function tests and to determine his ability to work. Post-bronchodilator spirometry revealed severe irreversible airway obstruction corresponding to a modified Medical Research Council grade of 2 on the dyspnea scale. His COPD Assessment Test score was 12, placing him in patient group D (high risk, more symptoms) based on the Global Initiative for Chronic Obstructive Lung Disease classification system. His maximum oxygen uptake (VO2max) was determined to be 19.16 ml/kg/min, as measured by the exercise stress test, and his acceptable workload for 8 h of physical work was calculated to be 6.51 ml/kg/min. His work tasks required an oxygen demand of 6.89 ml/kg/min, which exceeded the acceptable workload calculated. Accordingly, he was advised to adjust the work tasks that were deemed inappropriate for his exercise capacity. CONCLUSION: As COPD incidence is expected to rise, early COPD diagnosis and determination of fitness to work is becoming increasingly important. Performing the exercise stress test, to evaluate the functional capacity of workers with COPD, is considered an acceptable solution.
Airway Obstruction ; Classification ; Diagnosis ; Dyspnea ; Exercise Test* ; Humans ; Incidence ; Middle Aged ; Oxygen ; Pulmonary Disease, Chronic Obstructive* ; Ships ; Smoke ; Smoking ; Spirometry ; Symptom Assessment ; Weights and Measures

No abstract available.
Environmental Health* ; Housing* ; Life Style*