Mechanisms underlying the hormetic effect of conjugated linoleic acid: Focus on Nrf2, mitochondria and NADPH oxidases.

Nuclear factor erythroid 2-related factor2 (Nrf2) is a redox-sensitive transcription factor. Its activation by low dietary intake of ligands leads to antioxidant effects (eustress), while pro-oxidant effects (oxidative distress) may be associated with high doses. NADPH oxidases (NOXs) and the mitochondrial electron transport chain are the main sources of intracellular ROS, but their involvement in the biphasic/hormetic activity elicited by Nrf2 ligands is not fully understood. In this study, we investigated the involvement of NOX expression and mitochondrial function in the hormetic properties of omega-3 typically present in fish oil (FO) and conjugated linoleic acid (CLA) in the mouse liver. Four-week administration of FO, at both low and high doses (L-FO and H-FO) improves Nrf2-activated cyto-protection (by phase 2 enzymes), while a significant increase in respiration efficiency occurs in the liver mitochondria of H-FO BALB/c mice. Eustress conditions elicited by low dose CLA (L-CLA) are associated with increased activity of phase 2 enzymes, and with higher NOX1-2, mitochondrial defences, mitochondrial uncoupling protein 2 (UCP2), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) expression, compared with controls. Steatogenic effects (lipid accumulation and alteration of lipid metabolism) elicited by high CLA (H-CLA) elicited that are associated with oxidative distress, increased mitochondrial complex I/III activity and reduced levels of phase 2 enzymes, in comparison with L-CLA-treated mice. Our results confirm the steatogenic activity of H-CLA and first demonstrate the role of NOX1 and NOX2 in the eustress conditions elicited by L-CLA. Notably, the negative association of the Nrf2/PGC-1α axis with the different CLA doses provides new insight into the mechanisms underlying the hormetic effect triggered by this Nrf2 ligand.

Toxoplasma infection in individuals in central Italy: does a gender-linked risk exist?

An accurate estimate of the impact of toxoplasmosis on the population in Italy is not available. We performed a cross-sectional study on individuals living in Italy to assess: (1) differences in access to Toxo testing and in the prevalence of recent and past Toxoplasma gondii infection according to gender and age, and (2) the clinical impact of disease burden on the male patient subset. Reason for testing, condition of in- or outpatient and clinical data were analysed. Between-gender differences were observed in access to the test. Immunoglobulin M (IgM) prevalence was increased in males in the age range 5-34 years [odds ratio (OR) = 2.03, 95% confidence interval (CI) 1.18-3.49, p = 0.01), with a peak at 25-34 years. In females, it decreased in the age range 20-39 years (OR = 0.49, 95% CI 0.32-0.74, p = 0.0008). The attack rate of recent infection was twice as high for males than for females. Estimates pointed out 3.3 and 1.7 events in 1000 at-risk person-years in the male and female cohorts, respectively. Most IgM-positive subjects did not experience severe forms of toxoplasmosis, with 35% having lymphadenopathy. Chorioretinitis, systemic and neurological manifestations were also observed. Our findings suggest that the acute phase of toxoplasmosis is largely unapparent or clinically mild in this area. It is also possible that the disease burden for Toxoplasma infection in Italy is underestimated. Further study should focus on information acquisition and Toxo test access in hospital units for a better estimation of the real burden of mild and severe forms of the disease.

[Managing the hospitalizations for older patients in University Hospital of Pisa]. / L'andamento dei ricoveri ordinari relativi ai pazienti anziani in un' Azienda Ospedaliera di Alta Specializzazione.

We have analyzed hospitalizations of older people (> 64) from 2002 to 2005. Patients, discharges and stay in hospital have increased, the variation has been statistically significant. We have noticed the same trend about the rehospitalizations. Patients and discharges coming from ASL 5 and zone 4 have decreased in relation with all the elderly people. The reduction of stay in hospital and the decrease of rehospitalizations have been statistically significant.

[Extent of endemic Chlamydia trachomatis in the metropolitan area of Buenos Aires (Argentina)]. / Dimensión de la endemia por Chlamydia trachomatis en el área de la ciudad de Buenos Aires (Argentina).

BACKGROUND: In this report we inform laboratory results accumulated over ten years (1986-1995). The number of cases, and the geographic distribution, allow us to present a very reliable data about the dimension of Chlamydia trachomatis urogenital infections in Buenos Aires city and we also compare this profile with the prevalence of Neisseria gonorrhoeae in the same area and period of time. METHODS: Patients were females and males (aged from 15 to 49 years old) attending clinics not specialize in Sexually Transmitted Diseases (STD). Intent to isolation of C. trachomatis was done in McCoy cells culture. Patients for Neisseria gonorrhoeae investigation were a population assisted at the Clinic for STD of an University Hospital (aged from 15 to 75 years old). Study for detection of N. gonorrhoeae was developed by direct and conventional culture technics. RESULTS: 4128 endocervical samples from women with lower genital tract pathology were studied and C. trachomatis infection was detected in 25.6 +/- 4.8%. Over 1206 male urethral samples 29.5 +/- 4.47% shows positive cultures. Except for years 1989 and 1990 in which annual percentage of infected women showed slightly higher percentage over the global average, the results shows a very stable annual values, as it was also found in male patients. Infection in males shows a discrete tendency to be higher compare with values obtained in women. Global results of the evolution of prevalence of N. gonorrhoeae infection shows a very different pattern. Since 1992 we demonstrate a very significant decrease in the number of confirmed cases. CONCLUSIONS: We concluded that patients not attending a STD clinic, reveal a high and very stable endemic level of C. trachomatis lower tract urogenital infections. N. gonorrhoeae in this population is a very sporadic or null finding. Prevalence of Chlamydial infection in STD centers is even higher and also shows an stable profile. In people attending STD clinics N. gonorrhoeae shows a very different kinetics, with an important decrease in prevalence in the last five years.