Effects of anxiety on TNF-alpha levels during psychological stress

OBJECTIVES

Psychological stress can influence the immune system, which may result in stress-related illnesses. In this study, we investigated the effect of psychological stress and the coping skill on plasma cytokine levels.

MATERIALS AND METHODS

One hundred eighty-three students, at different stages of an academic year, participated in this study. Plasma tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-2 soluble receptor alpha, and IL-4 were measured and examined in relation to the measures of anxiety [State Anxiety Inventory (SAI)] and Bell Adjustment Inventory (BAI) score.

RESULTS

SAI scores were significantly higher in both midterm students (MTS) and examination-taking students (ETS), compared with the freshly admitted students (FAS). In addition, TNF-alpha levels were significantly different between the high- and the low-anxiety groups of ETS but not in MTS or FAS. The correlation between SAI scores and the BAI emotional scores was highest in the ETS group.

CONCLUSIONS

TNF-alpha level was significantly lower in the ETS group with high anxiety scores, and it is situation specific.

Production of fructosyl transferase by Aspergillus oryzae CFR 202 in solid-state fermentation using agricultural by-products

Fructosyl transferase (FTase) production by Aspergillus oryzae CFR 202 was carried out by solid-state fermentation (SSF), using various agricultural by-products like cereal bran, corn products, sugarcane bagasse,cassava bagasse (tippi) and by-products of coffee and tea processing. The FTase produced was used for the production of fructo-oligosaccharides (FOS), using 60% sucrose as substrate. Among the cereal bran used, rice bran and wheat bran were good substrates for FTase production by A. oryzae CFR 202. Among the various corn products used, corn germ supported maximum FTase production, whereas among the by-products of coffee and tea processing used, spent coffee and spent tea were good substrates, with supplementation of yeast extract and complete synthetic media. FTase had maximum activity at 60 degrees C and pH 6.0. FTase was stable up to 40 degrees C and in the pH range 5.0-7.0. Maximum FOS production was obtained with FTase after 8 h of reaction with 60% sucrose. FTase produced by SSF using wheat bran was purified 107-fold by ammonium sulphate precipitation (30-80%), DEAE cellulose chromatography and Sephadex G-200 chromatography. The molecular mass of the purified FTase was 116.3 kDa by SDS-PAGE. This study indicates the potential for the use of agricultural by-products for the efficient production of FTase enzyme by A. oryzae CFR 202 in SSF, thereby resulting in value addition of those by-products.

Proteus mirabilis and rheumatoid arthritis: no association with the disease

Proteus mirabilis (PM) is implicated in different studies in the pathogenesis of rheumatoid arthritis (RA) because of the structural homogeneity of its haemolysin B precursor with EQRRAA sequences in DRB 1 haplotype. The aim of the study was to compare the levels of antibodies specific to PM in the sera of patients with RA and healthy controls in our population. Serum samples from 78 consecutive RA patients and 75 healthy controls were analysed for the presence of IgG isotype and total immunoglobulins (IgG + IgA + IgM) against PM using enzyme-linked immunosorbent assay (ELISA) with two kinds of antigen preparations, whole bacteria and SDS-lysed bacterial extract. There was no significant increase in the concentrations of anti- Proteus antibodies (APA) in patients with RA compared to healthy controls in our population, when SDS-lysed bacterial extract or whole bacteria were used as antigen. The APA levels did not correlate with serum CRP levels. We conclude that P. mirabilis has no pathological or aggravating role in RA.

Proteus mirabilis and rheumatoid arthritis: no association with the disease

Proteus mirabilis(PM) is implicated in different studies in the pathogenesis of rheumatoid arthritis (RA) because of the structural homogeneity of its haemolysin B precursor with EQRRAA sequences in DRB 1 haplotype. The aim of the study was to compare the levels of antibodies specific to PM in the sera of patients with RA and healthy controls in our population. Serum samples from 78 consecutive RA patients and 75 healthy controls were analysed for the presence of IgG isotype and total immunoglobulins (IgG+IgA+IgM) against PM using enzyme-linked immunosorbent assay (ELISA) with two kinds of antigen preparation, whole bacteria and SDS-lysed bacterial extract. There was no significant increase in the concentrations of anti- Proteus antibodies (APA) in patients with RA compared to healthy controls in our population, when SDS-lysed bacterial extract or whole bacteria were used as antigen. The APA levels did not correlate with serum CRP levels. Infection with P. mirabilis is found to have no pathological or aggravating role in RA.

Predicting the behavior of Escherichia coli introduced as a postprocessing contaminant in shrikhand, a traditional sweetened lactic fermented milk product

The increasing popularity of traditional milk-based foods has placed emphasis on the need for microbial safety in food-chain establishments, as there are ample possibilities for foodborne pathogens to occur as postprocessing contaminants. The behavioral pattern of an enterotoxigenic strain of Escherichia coli D 21 introduced as a postprocessing contaminant in shrikhand, a traditional sweetened lactic fermented milk product, was studied with variables of initial inoculum (4.3, 5.3, and 6.3 log10 CFU/g), storage temperature (4, 10, and 16 degrees C), and storage period (4, 9, and 14 days). During storage of shrikhand prepared individually with Lactobacillus delbruecki ssp. bulgaricus CFR 2028 and Lactococcus lactis ssp. cremoris B-634, there was a steady decrease in the viable count of E. coli that was proportional to the initial inoculum of E. coli introduced into shrikhand. The data were subjected to multivariate analysis, and equations were derived to predict the behavior of E. coli in shrikhand. The predicted values for the probable survival of E. coli showed good agreement with the experimental values with a majority of these predictions being fail-safe. The values of statistical indices showed that the model fits ranged between extremely good and satisfactory. Response surface plots were generated to describe the behavioral pattern of E. coli. The derived models and response surface plots enabled prediction of the survival of E. coli in shrikhand as a function of initial inoculum levels, storage temperatures, and storage periods of shrikhand. These predictions were valid within the limits of the experimental variables used to develop the model.