Alterations of serum and saliva oxidative markers in patients with bronchial asthma.

BACKGROUNDS: The development of asthma is highly affected by exposure to exogenous and endogenous oxidative molecules, but the impact of this exposure on the pathophysiology of asthma has received little attention. OBJECTIVES: Evaluating group of selective oxidative stress markers as a tool in the management of asthma disease. METHODS: In comparison with matched healthy controls, levels of the oxidant and antioxidant markers: lipid peroxidation malondialdehyde (MDA), Total glutathione (tGSH), Uric acid (UA), Glutathione peroxidase (GPx), Catalase (CAT) superoxide dismutase (SOD), and Total antioxidant capacity (TAC) were assessed in serum and saliva of different asthma groups. RESULTS: All oxidative markers in serum and saliva of asthma patients showed significant alterations from normal healthy controls (P < 0.05), except the salivary SOD (P = 0.441). Their levels in serum were significantly correlated with asthma severity (P < 0.05), and the distinguishing between childhood and adult asthma was significantly accomplished by GPx, SOD, TAC markers (P < 0.05). However, in patients with childhood asthma no significant differences were detected between the levels of GPx, CAT, UA, MDA in serum and saliva samples (P > 0.05). CONCLUSION: Determination of the oxidative markers GPx, CAT, UA in serum or saliva can distinguish asthma from healthy states. The serum levels of UA and TAC are highly effective in monitoring asthma severity, while the salivary GPx, CAT, UA, MDA are beneficial in the management of childhood asthma. Discrimination of the age factor between asthma groups can be achieved by testing GPx, SOD, TAC in serum.

Association of RETN +299(G>A) polymorphism with type two diabetes mellitus.

The global prevalence of type-two diabetes mellitus (T2DM) makes it a disease of public health concern. T2DM is strongly linked with insulin resistance caused by increased levels of visceral fat. Visceral fat secretes several adipocytokines that regulate body metabolism. Resistin is one of these adipocytokines which is encoded by the RETN gene. Herein, we tested the association of the RETN +299(G>A) and -420(C>G) single nucleotide polymorphisms (SNPs) with T2DM. T2DM patients (n=282) and healthy subjects (n=125) were included in the study. Subjects with metabolic syndromes other than diabetes were excluded. Genotyping of subjects was performed using PCR-RFLP. The +299(G>A) SNP was associated with T2DM (P=0.038). The AA genotype was higher in T2DM (17%) compared to controls (8%) with an odd ratio of 2.16 and 95% CI of 1.34 to 4.56. With respect to -420(C>G) SNP, no significant association was found with the risk of T2DM (P=0.128). The haplotype analysis of the examined SNPs indicated that the CA haplotype of the -420 and +299 SNPs in RETN was associated with T2DM risk (P=0.004; odd ration 4.0, 95% CI: 1.56-10.0). In conclusion, the present findings suggest a role of the RETN locus in modulating the risk of T2DM.

Synchrony of G6PD activity and RBC fragility under oxidative stress exerted at normal and G6PD deficiency.

OBJECTIVES: To investigative the effects of oxidative stress simultaneously on Glucose-6-phosphate dehydrogenase (G6PD) activity and RBC fragility under normal and G6PD defective conditions. METHODS: The effects of several nitric oxide (NO) generating compounds and sulfhydryl blocking agents were simultaneously tested in vitro on hemolysate G6PD activities and RBC fragility. These effects were compared between normal subjects and patients with G6PD deficiency. RESULTS: The NO donor compounds nitrosocysteine, nitrosoarginine and diethylamine caused strong inhibition on normal and defective G6PD activities, while a similar inhibition was observed only at higher concentrations of the sulfhydryl blocking agents: 2-mercaptoethanol , cysteine and reduced glutathione. All these oxidative compounds promoted RBC hemolysis in parallel to their inhibition extents on G6PD activities. The protection of RBC from this hemolysis was achieved by preincubation with NADPH or SNP but not NAD(+) compound. CONCLUSION: A concomitant response of G6PD activities and RBC fragility towards the oxidative stress was established.

Copper uptake by Pseudomonas aeruginosa isolated from infected burn patients.

Pseudomonas aeruginosa was isolated from infected burn patients and characterized by standard biochemical tests. The in vitro copper uptake was compared between this isolated pathogenic strain and two non-pathogenic control strains of gram positive bacteria Bacillus thuringiensis strain Israelis as well as gram negative bacteria Enterobacter aerogenes. Maximum copper uptake of 470 ppm/g biomass was obtained by P. aeruginosa strain, while the control strains B. thuringiensis and Enterobacter aerogenes had copper uptake of 350 and 383 ppm/g biomass, respectively. However, the lowest copper uptake (60 ppm/g biomass) was observed with another control the saprophytic strain Pseudomonas (Shewanella) putrefaciens. A further investigation regarding the effect of copper toxicity on bacterial growth, gave an MIC score of 600 ppm for P. aeruginosa strain compared to 460 and 300 ppm for the two gram positive and gram negative control strains, respectively. In tandem with these in vitro findings, blood analysis on burn patients infected with P. aeruginosa has indicated a selective decrease of copper (hypocupremia) and ceruloplasmin plasma levels. The iron metabolism was also affected by this copper deprivation leading to a similar decrease in plasma levels of PCV, iron, total iron binding capacity, and transferrin. All these hematological changes were significantly different (P < 0.05) from the matched group of non-infected burn patients. The observed hypocupremia in infected burn patients was attributed to demanding scavenger ability by P. aeruginosa strain for the copper of plasma.

Antibacterial activity in vitro of Thymus capitatus from Jordan.

This study was carried out to evaluate the antibacterial activity of aqueous and organic extracts of Thymus capitatus L. (Lamiaceae) leaves and stems. Dried ground powder leaves and stems were extracted with water (aqueous extracts), ethanol, dichloromethane and hexane (Soxhlet extracts). The antibacterial activity of these extracts was evaluated against bacteria using disc diffusion method. The result obtained showed that the leaves had stronger antibacterial activity than the stems extracts. The ethanolic extract had the highest yield products and the high antibacterial activity than all other solvents. The results suggest that essential oil as non-polar organic compounds could be the main active compounds in this plant. Therefore the antibacterial activity of leaves ethanol extracts (LEE) was compared with essential oils leaves extracts (LEO) of T. capitatus. The LEO showed greater antibacterial activity than LEE. The LEO showed a broad spectrum of antibacterial activity and the Pseudomonas aeruginosa was the most sensitive bacteria.

Effects of carbon source and Vitreoscilla hemoglobin (VHb) on the production of beta-galactosidase in Enterobacter aerogenes.

At fixed concentration (0.5%), lactose and galactose acted as inducers while glucose and other tested carbon sugars showed repression effects on beta-galactosidase production in Enterobacter aerogenes strain. The expression of Vitreoscilla hemoglobin gene (vgb) in this bacterial strain managed to overcome the repression effects as well as improving the induction of beta-galactosidase formation by carbon sources. In parallel, the bacterial O(2) consumption was increased correspondingly to the vgb induction of beta-galactosidase synthesis. When Enterobacter aerogenes strains were grown at the incubation temperature 42 degrees C, about 5-fold higher enzyme productivity was obtained than with a similar incubation at 37 degrees C. The bacterial growth expressed as biomass yield had a different optimum temperature and was not influenced to the same extent by variations in the carbon sources. These data are discussed in terms of proposed enhancement in beta-galactosidase productivity by vgb expression as well as its significance to improve the technology of whey processing.