Decreasing the oxidant stress from paraquat in isolated perfused rat lung using captopril and niacin

The abilities of captopril and niacin to protect against the lung toxicity of paraquat (PQ) were studied. The anti-oxidative action of captopril, an angiotensin-converting enzyme inhibitor, appears to be attributable to the sulphahydryl group (SH) in the compound, which gives captopril the ability to scavenge reactive oxygen species. Niacin replenishes the NAD and ATP depletion caused by reactive oxygen species. PQ causes lung damage in man and in several species of laboratory animals. The damage is initially manifested by hemorrhage and edema, and later by consolidation of the lung and fibrosis development. In this study, the lungs of male Wistar rats (250-300 g in weight) were perfused by Krebs-Ringer buffer alone (control), niacin (150 microM), captopril (10 microM) and PQ (600 microM) in perfusion fluid, and the biochemical changes that occurred in isolated rat lung were examined within 1 h and compared to PQ alone. The results show that captopril significantly decreases the lung weight/body weight ratio when used as a pretreatment and a post-treatment to captopril (p<0.0001). The results also show that captopril (10 microM) and niacin (150 microM) significantly decreases PQ-induced lung toxicity. Lactate dehydrogenase (LDH) activity significantly decreased in treatment groups as compared to the PQ group (p<0.0001). This study suggests that paraquat causes increased lipid peroxidation and LDH activity and decreased glutathione (GSH) and total protein in isolated perfused rat lung. These effects are reduced under these experimental conditions by captopril and niacin.

Respiratory disorders associated with occupational inhalational exposure to bioaerosols among wastewater treatment workers of petrochemical complexes

Background:

Workers in wastewater treatment plants are exposed to a wide range of chemicals as well as biological contaminants.

Objective:

To ascertain whether exposure to bio-aerosols under the normal working conditions in wastewater treatment plants is associated with any significant changes in the prevalence of respiratory symptoms and lung function capacities.

Methods:

198 employees of wastewater treatment plants and 99 unexposed persons were studied. American thoracic society (ATS) standard respiratory symptom questionnaire was used to determine the prevalence of respiratory symptoms. Pulmonary function tests were conducted for each participant.

Results:

The prevalence of respiratory symptoms among exposed persons was significantly higher than that of unexposed people. Mean values of most pulmonary function test parameters were significantly lower in the exposed compared to the comparison group persons.

Conclusion:

Increased prevalence of respiratory symptoms and decrements in pulmonary function test parameters may be attributed to exposure to bio-aerosols released from wastewater treatment plants.

On intersection graph of intuitionistic fuzzy submodules of a module

There are some interesting relations between submodules of a module and its intuitionistic fuzzy (IF) submodules. In this paper we investigate some relationshipsbetween submodules of a module and its IFsubmodules. Then we introduce a graph structure on IFsubmodules of a module and obtain some properties of it, that is the main goal of this paper. We define the intersection graph of submodules of a module M(G) and we show that a submodule Nof Mis a center in MGif and only if IFNis a center in IFG. We get some relationships between IFsubmodules of a module and their supports, as vertices of IFgraph and crisp graph of a module M, respectively. We show that an IFsubmodule Aof Mis center in IFgraph of Mif and only ifAis a center in crisp graph of M.In prime ring R, we show that every vertex of intersection graph of IFideals of Ris center. In general the nature of intersection graph of IFsubmodules of a module under intersection, homomorphic images, finite sum and other algebraic operations of its vertices, are investigated.