Long-term effects of chromium on morphological and immunological parameters of Wistar rats.

Hexavalent chromium raises high concern because of its wide industrial applications and reported toxicity. Long-term (135 days) oral exposure of Wistar rats to chromium in the form of K2Cr2O7 (exposed group~20 mg/kg/day) led to a decrease in thymus mass and thymocytes' number and caused structural and functional changes in the lymph nodes and spleen, namely lymphoreticular hyperplasia and plasmocytic macrophage transformation. Programmed cell death was increased in both thymocytes and splenocytes and decreased in lymphocytes in the T-zones of spleen and lymph nodes. Moreover, Cr (VI) administration decreased myeloid cells' and neutrophils' number, while it increased lymphoid and erythroid cells' number in bone marrow. Cr (VI) immune system effects seem to be related to oxidative stress induction, as depicted by the increased levels of diene conjugates and malondialdehyde in the spleen and liver and by the decreased activity of catalase and superoxide dismutase in rats' erythrocytes. In addition, exposure to Cr (VI) decreased copper, nickel and iron concentrations in blood and liver, while Cr levels in blood, spleen and liver were increased, as expected. The observed changes in the series of immunological parameters studied contribute to the development of new approaches for the prevention of low level Cr exposure toxicity.

Cardioprotective effects of insulin on carbon monoxide-induced toxicity in male rats.

Carbon monoxide (CO) poisoning is a significant cause of death especially in developing countries. The current study investigated cardioprotective effects of insulin in CO-poisoned rats. Male rats were exposed to 3000 ppm CO for 1 h. Insulin (100 and 120 U/kg intraperitoneally) was immediately administered after CO exposure and on the next 4 days, on a daily basis (a total of 5 doses). On day 5, animals were euthanized, and the hearts were harvested for Western blotting and histopathological studies. The electrocardiograms (ECG) were recorded postexposure to CO and after the completion of insulin treatment period. Histopathological evaluations showed reduction of myocardial necrosis in insulin-treated animals compared to controls. BAX/BCL2 ratio, as a proapoptotic index, was significantly reduced in treatment groups ( p < 0.01). The ECG findings showed no differences among groups; also, compared to control animals, myocardial Akt levels were not markedly affected by insulin. The current study showed that insulin significantly reduces myocardial necrotic and apoptotic indices in CO-poisoned rats.

Simulating real-life exposures to uncover possible risks to human health: A proposed consensus for a novel methodological approach.

In real life, consumers are exposed to complex mixtures of chemicals via food, water and commercial products consumption. Since risk assessment usually focuses on individual compounds, the current regulatory approach doesn't assess the overall risk of chemicals present in a mixture. This study will evaluate the cumulative toxicity of mixtures of different classes of pesticides and mixtures of different classes of pesticides together with food additives (FAs) and common consumer product chemicals using realistic doses after long-term exposure. Groups of Sprague Dawley (CD-SD) rats (20 males and 20 females) will be treated with mixtures of pesticides or mixtures of pesticides together with FAs and common consumer product chemicals in 0.0, 0.25 × acceptable daily intake (ADI)/tolerable daily intake (TDI), ADI/TDI and 5 × ADI/TDI doses for 104 weeks. All animals will be examined every day for signs of morbidity and mortality. Clinical chemistry hematological parameters, serum hormone levels, biomarkers of oxidative stress, cardiotoxicity, genotoxicity, urinalysis and echocardiographic tests will be assessed periodically at 6 month intervals. At 3-month intervals, ophthalmological examination, test for sensory reactivity to different types of stimuli, together with assessment of learning abilities and memory performance of the adult and ageing animals will be conducted. After 24 months, animals will be necropsied, and internal organs will be histopathologically examined. If the hypothesis of an increased risk or a new hazard not currently identified from cumulative exposure to multiple chemicals was observed, this will provide further information to public authorities and research communities supporting the need of replacing current single-compound risk assessment by a more robust cumulative risk assessment paradigm.

The heart failure pandemic: The clinical and economic burden in Greece.

BACKGROUND: The objective of this study was to identify the epidemiological and clinical characteristics of heart failure (HF) patients in Greece as well as the economic burden and the distribution of costs for the management of the disease. METHODS: Eight Greek secondary and tertiary cardiology centres from different cities have participated in a prospective, observational survey, the ESC HF Pilot Survey. 307 patients with HF, 177 hospitalised and 130 outpatients, have been recruited and monitored for 12months. Clinical and epidemiological data, along with data on mortality, hospitalisations and health care resources used have been collected. The economic evaluation was conducted from the social security system perspective. RESULTS: The annual mortality rate was 24.3% for the hospitalised patients vs 7.7% for the outpatients (P<0.001) and the annual rehospitalisation rate was 42.9% vs 19.2% respectively (P<0.001). Kaplan-Meier analyses revealed that patients with kidney dysfunction, S3 gallop and higher NYHA class have a significantly worse survival. The mean annual economic burden of the social security system per HF patient was estimated at €4411±4764. About two thirds of this cost is due to in-patient care. CONCLUSIONS: Despite the progress in the management of the disease, about one in four hospitalised patients dies and four in ten are rehospitalised in less than one year. Moreover, the disease imposes a significant economic burden for the social security system and national economy. Their findings suggest that there is still need of more effective drug treatment and efficient disease management programs focused in the reduction of the hospital admissions.

Cardiotoxicity in rabbits after a low-level exposure to diazinon, propoxur, and chlorpyrifos.

Lethal cardiac complications leading to death and various arrhythmias have been reported after organophosphate and/or carbamate poisonings. The present study focuses on the long-term effects of repeated low-level exposure to diazinon, propoxur, and chlorpyrifos (CPF) on cardiac function in rabbits. The yearly based experimental scheme of exposure consisted of two oral administration periods, lasting 3 months and 1 month each, interrupted by an 8-month washout period (total duration 12 months). At the end of the experimental scheme, the rabbits underwent an echocardiographic evaluation under sedation, after which they were killed and the tissue and serum samples were collected. A mild localized cardiotoxic effect was established by echocardiography for the three pesticides tested. Severe histological alterations were identified, especially in the diazinon-treated animals in agreement with increased persistence of this pesticide established in the cardiac tissue. In addition, all pesticides tested increased the oxidative stress and oxidative modifications in the genomic DNA content of the cardiac tissues, each one following a distinct mechanism.

Electrocardiographic findings compatible with Brugada syndrome in a patient with febrile respiratory infection.

Brugada syndrome is an inherited autosomal dominant-type disease characterized by ST-segment abnormalities and increased fatal ventricular tachyarrhythmias. We hereby present a 57-years-old patient with no symptoms or history of cardiovascular disease, diagnosed with febrile respiratory infection (39℃). Electrocardiographic (ECG) findings were typical of Brugada-like type I syndrome that gradually turned to Brugada type II and III, following fever remission, and finally became normal. Other clinical evaluation tests (echocardiographic evaluation, treadmill stress test, Holter ECG, procainamide provocation test) did not relate to Brugada syndrome.

The prognostic impact of allopurinol in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention.

Oxidative stress has been shown to increase after acute myocardial infarction and during coronary reperfusion. Allopurinol inhibits xanthine oxidase, an enzyme involved in reperfusion injury. In this study, 40 patients with ST elevation myocardial infarction and symptoms' onset 3-12 h, who underwent primary coronary intervention, were administered either allopurinol (loading dose 400 mg followed by 100 mg for 1 month--group A, 21 patients), or placebo (group B). Allopurinol resulted in a more effective ST-E recovery (P<0.05 for all comparisons) and lower peak values of troponin I (P=0.04), CPK (P=0.01) and CK-MB (P=0.03). After 1-month follow-up period, 13% lower incidence of major adverse cardiac events (P=0.002) was also observed in group A, whereas no significant differences in the EF were detected between the groups studied. In our study population, allopurinol administration was beneficial concerning tissue reperfusion, myocardial injury and clinical outcomes.

Medication use by athletes during the Athens 2004 Paralympic Games.

OBJECTIVE: To examine the use of food supplements and pharmaceutical preparations by elite Paralympic athletes. DESIGN: Survey study. SETTING: Athens 2004 Paralympic Games. PARTICIPANTS: Data obtained from two sources: (i) athletes' declaration of intake of drugs/supplements recorded on the Doping Control Official Record during sample collection for doping control; (ii) athletes' application forms for granting of a therapeutic use exemption. MAIN OUTCOME MEASURES: Classification of declared food supplements according to the active ingredient and medications according to therapeutic actions and active compounds. RESULTS: 64.2% of the athletes tested for doping control declared use of medications or food supplements, and 81.3% of these athletes declared intake of fewer than four preparations. Non-invasive routes of administration dominated. Food supplements (42.1%) were popular, and drugs used to treat several pathological conditions noted. Non-steroidal anti-inflammatory agents and analgesics were commonly used (9.8% and 5.6%, respectively). The prevalence of inhaled beta2-agonist use (4.8%) was higher than expected and exceeded that at the Athens Olympic Games. CONCLUSIONS: This review, the first to examine elite Paralympic athletes, shows a more rational approach to the use of medication and food supplements, but a similar consumption pattern to that of athletes at the Athens Olympic Games. Because of the dearth of such studies, consumption trends among Paralympic athletes remain unclear. The need to counsel athletes with disabilities on their nutritional needs is confirmed, and close monitoring by healthcare professionals is recommended.