Acute and chronic effects of cadmium on blood homeostasis of an estuarine crab, Chasmagnathus granulata, and the modifying effect of salinity

Whole body oxygen consumption and some hemolymph parameters such as pH, partial pressure of gases, level of ions and lactate were measured in the estuarine crab Chasmagnathus granulata after both acute (96 h) and chronic (2 weeks) exposure to cadmium at concentrations ranging from 0.4 to 6.3 mg/l. In all instances, the crabs developed hemolymph acidosis, but no respiratory (increased PCO2) or lactate increases were evident. Hemolymph levels of sodium and calcium were always increased by cadmium exposure. The chronic toxicity of cadmium was enhanced at 12‰ salinity, even causing a significantly higher mortality in comparison with the higher salinity (30‰) used. A general metabolic arrest took place at 12‰ salinity in the crabs chronically exposed to cadmium, as indicated by decreases of oxygen consumption and PCO2, an increase of PO2, along with no changes in lactate levels. These imbalances were associated with severe necrosis and telangiectasia in the respiratory gills, probably leading to respiratory impairment and finally histotoxic hypoxia and death of the animals.

L-carnitine as an ergogenic aid for patients with chronic obstructive pulmonary disease submitted to whole-body and respiratory muscle training programs

The effects of adding L-carnitine to a whole-body and respiratory training program were determined in moderate-to-severe chronic obstructive pulmonary disease (COPD) patients. Sixteen COPD patients (66 ± 7 years) were randomly assigned to L-carnitine (CG) or placebo group (PG) that received either L-carnitine or saline solution (2 g/day, orally) for 6 weeks (forced expiratory volume on first second was 38 ± 16 and 36 ± 12%, respectively). Both groups participated in three weekly 30-min treadmill and threshold inspiratory muscle training sessions, with 3 sets of 10 loaded inspirations (40%) at maximal inspiratory pressure. Nutritional status, exercise tolerance on a treadmill and six-minute walking test, blood lactate, heart rate, blood pressure, and respiratory muscle strength were determined as baseline and on day 42. Maximal capacity in the incremental exercise test was significantly improved in both groups (P < 0.05). Blood lactate, blood pressure, oxygen saturation, and heart rate at identical exercise levels were lower in CG after training (P < 0.05). Inspiratory muscle strength and walking test tolerance were significantly improved in both groups, but the gains of CG were significantly higher than those of PG (40 ± 14 vs 14 ± 5 cmH2O, and 87 ± 30 vs 34 ± 29 m, respectively; P < 0.05). Blood lactate concentration was significantly lower in CG than in PG (1.6 ± 0.7 vs 2.3 ± 0.7 mM, P < 0.05). The present data suggest that carnitine can improve exercise tolerance and inspiratory muscle strength in COPD patients, as well as reduce lactate production.

Whole-body vibration decreases the proliferativeb response of TCD4+ cells in elderly individuals with knee osteoarthritis

The aim of this study was to investigate the effect of adding whole-body vibration (WBV; frequency = 35 to 40 Hz; amplitude = 4 mm) to squat training on the T-cell proliferative response of elderly patients with osteoarthritis (OA) of the knee. This study was a randomized controlled trial in which the selected variables were assessed before and after 12 weeks of training. Twenty-six subjects (72 ± 5 years of age) were divided into three groups: 1) squat training with WBV (WBV, N = 8); 2) squat training without WBV (N = 10), and 3) a control group (N = 8). Women who were ≥60 years of age and had been diagnosed with OA in at least one knee were eligible. The intervention consisted of 12 uninterrupted weeks of squatting exercise training performed 3 times/week. Peripheral blood mononuclear cells were obtained from peripheral blood collected before and after training. The proliferation of TCD4+ and TCD8+ cells was evaluated by flow cytometry measuring the carboxyfluorescein succinimidyl ester fluorescence decay before and after the intervention (∆). The proliferative response of TCD4+ cells (P = 0.02, effect size = 1.0) showed a significant decrease (23%) in the WBV group compared to the control group, while there was no difference between groups regarding the proliferative response of TCD8+ cells (P = 0.12, effect size = 2.23). The data suggest that the addition of WBV to squat exercise training might modulate T-cell-mediated immunity, minimizing or slowing disease progression in elderly patients with OA of the knee.

Studies on mosquitoes (Diptera: Culicidae) and anthropic environment: 1- Parity of blood seeking Anopheles (Kerteszia) in South-Eastern Brazil

Populations of Anopheles (Kerteszia) were sampled fortnightly over a one-year period (August 1991 to July 1992) at Ribeira Valley, S. Paulo State, Brazil. Indoor and outdoor collections were made on human bait at evening crepuscular period. The Polovodova technique for age grading was applied to 3,501 females of Anopheles cruzii and to 416 females of An. bellator. That sample represented 34.4% of the total number of mosquitoes collected. The most abundant species found was An. cruzii. However, An. bellator showed an endophagy that was almost three times greater than that of An. cruzii. The overall parous rate was 25.4% and uniparity was practically dominant one. A proportion of 26.9% of An. cruzii and 12.0% of An. bellator were found to be uniparous. Only three outdoor females of the former species (0.1%) showed biparity. Parity of An. cruzii was higher in females caught outdoors than in those caught indoors. Nevertheless, 497 nulliparous females examined (417 cruzii and 80 bellator) had ovaries that had advanced to Christophers and Mer stages III to V. These results imply that these females had already practised hematophagy. Relating these results to those from the parous females, a high statistical significance was found, leading to the conclusion that gonothophic discordance is a common pattern among these anophelines. Further, these results obtained with human bait catches strongly suggest that nearly 38.0% of these host-seeking females had already taken at least one previous blood-meal. So it is possible that enough time could thus be available for the plasmodian development in the vectors.

Studies on mosquitoes (Diptera: Culicidae) and anthropic environment: 11 - Biting activity and blood-seeking parity of Anopheles (Kerteszia) in South-Eastern Brazil

An. (Ker.) cruzii and An. (Ker.) bellator were monitored by the use of human bait and Shannon trap collections during a one-year period in 1994. Indoor and outdoor collections were made on human bait and inside the forest environment a Shannon trap was used. Both were undertaken in the evening crepuscular period. Results showed a greater abundance of An. cruzii in the forest, where as An. bellator was more abundant in the domiciliary environment. Through the application of the Polovodova method an age grading was established. Computing the parous and nulliparous females with Christopher's Stage III and above, more than 30.0% of blood-seeking specimens of both anophelines had had a previous blood meal. The higher abundance of An. bellator as compared with that of An. cruzii in the domiciliary environment may be explained by the influence of the neighboring low-lying coastal islands of the estuary system.

Chagas disease in an area of recent occupation in Cochabamba, Bolivia

INTRODUCTION: A descriptive, entomological and seroepidemiological study on Chagas disease was conducted in a place of recent occupation on the outskirts of Cochabamba, Bolivia: Avaroa/Primer de Mayo (population:3,000), where the socio-economic level is low and no control measures have been made available. METHODS: The immunofluorescent antibody test (IFAT) was used for IgG and IgM anti-Trypanosoma cruzi antibodies in filter paper bloodspot eluates from 128 subjects (73 females, 55 males) selected by systematic sampling. Concerning each subject age, gender, birthplace, occupation, duration of residence and building materials used in their houses were recorded. Vectors were captured both in domestic and peridomestic environments. RESULTS: Seropositive, 12.5% (16/128): females, 15.1% (11/73); males, 9.1% (5/55). Average time of residence: 6.1 years for the whole population sample and 7.4 years for the seropositive subjects. Most houses had adobe walls (76.7% , n= 30), galvanized iron rooves (86.7%) and earthen floors (53.4%) 80% of the walls had crevices. One hundred forty seven specimens of Triatoma infestans were captured, of which 104 (70.7%) were domestic, and 1 peridomestic Triatoma sordida. Precipitin host identification: birds, 67.5%; humans, 27.8%; rodents, 11.9%; dogs, 8.7%; cats, 1.6%. House infestation and density indices were 53.3 and 493.0 respectively. We found 21 (14.3%) specimens of T. infestans infected with trypanosomes, 18 (85.7%) of which in domestic environments. DISCUSSION: The elements for the vector transmission of Chagas disease are present in Avaroa/Primer de Mayo and the ancient custom of keeping guinea pigs indoors adds to the risk of human infection. In neighboring Cochabamba, due to substandard quality control, contaminated blood transfusions are not infrequent, which further aggravates the spread of Chagas disease. Prompt action to check the transmission of this infection, involving additionally the congenital and transfusional modes of acquisition, is required.

HTLV-I/II and blood donors: determinants associated with seropositivity in a low risk population

OBJECTIVE: Blood donors in Brazil have been routinely screened for HTLV-I/II since 1993. A study was performed to estimate the prevalence of HTLV-I/II infection in a low risk population and to better understand determinants associated with seropositivity. METHODS: HTLV-I/II seropositive (n=135), indeterminate (n=167) and seronegative blood donors (n=116) were enrolled in an open prevalence prospective cohort study. A cross-sectional epidemiological study of positive, indeterminate and seronegative HTLV-I/II subjects was conducted to assess behavioral and environmental risk factors for seropositivity. HTLV-I/II serological status was confirmed using enzyme-linked immunosorbent assay (EIA) and Western blot (WB). RESULTS: The three groups were not homogeneous. HTLV-I/II seropositivity was associated to past blood transfusion and years of schooling, a marker of socioeconomic status, and use of non-intravenous illegal drugs. CONCLUSIONS: The study results reinforce the importance of continuous monitoring and improvement of blood donor selection process.

Trypanosoma cruzi prevalence and clinical forms in blood donor candidates in Brazil

The prevalence and clinical forms of Trypanosoma cruzi were evaluated among blood donor candidates attended at a general hospital in Rio de Janeiro, Brazil, from January 1997 to April 1999. The investigation was done by means of the indirect hemagglutination test and was confirmed via ELISA. Data were collected from clinical examinations, conventional electrocardiogram, chest radiography and echocar-diography. The results showed that despite Trypanosoma cruzi prevalence of 1.17% (128 patients), mainly in males aged 40 years or over, 70.8% of these patients, mainly males aged 19 to 39 years, demonstrated abnormalities that allowed the diagnosis of cardiopathy and/or esophagopathy. This once again corroborates the importance of Trypanosoma cruzi infection in urban centers.

Blood glucose control in diabetes patients seen in primary health care centers

OBJECTIVE: To identify factors associated to poor glycemic control among diabetic patients seen at primary health care centers. METHODS: A cross-sectional study was carried out in a sample of 372 diabetic patients attending 32 primary health care centers in southern Brazil. Data on three hierarchical levels of health unit infrastructure, medical care and patient characteristics were collected. RESULTS: The frequency of poor glycemic control was 50.5%. Multivariate analysis (multilevel method) showed that patients with body mass indexes below 27 kg/m², patients on oral hypoglycemic agents or insulin, and patients diagnosed as diabetic over five years prior to the interview were more likely to present poor glycemic control when compared to their counterparts. CONCLUSIONS: Given the hierarchical data structuring, all associations found suggest that factors associated to hyperglycemia are related to patient-level characteristics.

Young people's blood alcohol concentration and the alcohol consumption city law, Brazil

The paper assesses blood alcohol concentration and risk behaviors for traffic accidents before and after the implementation of a law which prohibits the use of alcoholic beverages on city gas stations. In Porto Alegre, Southern Brazil, young people go out at night and drive to gas station convenience stores to buy alcoholic beverages which are consumed on the premises of parking lots in gas stations. Data were obtained from self-administered questionnaires and breath analyzers in two cross-sectional collections with purposive samples of youngsters in May and July 2006 (n=62, and n=50, respectively). There were no significant differences between the groups before and after the city law was passed. Blood alcohol concentration greater than 0.06% was found in 35.5% of pre-law group and 40% of post-law group (p=0.62). Results point out heavy alcohol use in both groups, which did not change after the law was passed.

Size at birth and blood pressure in young adults: findings from a Brazilian birth cohort study

^len^lpt^aOBJETIVO: Descrever a prevalência de pressão arterial limítrofe (PAL) e hipertensão (HT) entre adultos jovens e avaliar a associação entre tamanho ao nascer e PAL/HT. MÉTODOS: Dados foram coletados do primeiro estudo brasileiro de coorte de nascimentos em Ribeirão Preto (sudeste do Brasil), iniciado em 1978/79. De 6.827 recém-nascidos de parto único hospitalar, 2.060 foram avaliados aos 23/25 anos. Foram realizadas coleta de sangue, avaliação antropométrica e obtidas informações sobre ocupação, escolaridade, hábitos de vida e doenças crônicas. Pressão arterial (PA) foi classificada em: 1) PAL: PA sistólica (PAS) ≥ 130 e < 140 mm Hg e/ou PA diastólica (PAD) ≥ 85 e < 90 mmHg; 2) HT: PAS ≥ 140 e/ou PAD ≥ 90 mm Hg. Foi aplicado modelo de regressão logística politômica. RESULTADOS: A prevalência de PAL foi de 13,5% (homens 23,2%) e a de HT, 9,5% (homens 17,7%). PAL foi independentemente associada com sexo masculino (RR 8,84; IC95%: 6,09;12,82), comprimento ao nascer ≥ 50 cm (RR 1,97; 1,04; 3,73), índice de massa corporal (IMC) ≥ 30 kg/m² (RR 3,23; 2,02; 5,15) e circunferência de cintura alterada (RR 1,61; 1,13;2,29), enquanto HT associou-se com sexo masculino (RR 15,18; 8,92;25,81), IMC ≥ 30 kg/m² (RR 3,68; 2,23;6,06), circunferência de cintura alterada (RR 2,68; 1,77;4,05) e glicemia elevada (RR 2,55; 1,27;5,10), mas não com comprimento ao nascer. CONCLUSÕES: As prevalências de PAL e HT entre os adultos jovens dessa coorte foram maiores em homens que em mulheres. Maior comprimento ao nascer foi associado com PAL, mas não com HT, enquanto peso ao nascer não foi associado com PAL ou HT. Fatores de risco do adulto explicaram a maioria dos aumentos de PAL ou HT.^les^aOBJETIVO: Describir la prevalencia de presión arterial limítrofe (PAL) e hipertensión (HT) entre adultos jóvenes y evaluar la asociación entre tamaño al nacer y PAL/HT. MÉTODOS: : Los datos fueron colectados en el primer estudio de cohorte de nacimientos brasileño en Ribeirao Preto (sureste de Brasil), iniciado en 1978/79. De 6.827 recién nacidos de parto único hospitalario, 2.060 fueron evaluados a los 23/25 años. Se realizaron colecta de sangre, evaluación antropométrica y obtenidas informaciones sobre ocupación, escolaridad, hábitos de vida y enfermedades crónicas. Presión arterial (PA) fue clasificada en: 1) PAL: PA sistólica (PAS) ≥ 130 y < 140 mm Hg y/o PA diastólica (PAD) ≥ 85 y < 90 mm Hg; 2) HT: PAS ≥ 140 y/o PAD ≥ 90 mm Hg. Se aplicó modelo de regresión logística politómica. RESULTADOS: La prevalencia de PAL fue de 13,5% (hombres 23,2%) y la de HT, 9,5% (hombres 17,7%). PAL fue independientemente asociada con sexo masculino (Riesgo Relativo - RR) 8,84; 95%IC: 6,09;12,82), estatura al nacer ≥ 50 cm (RR 1,97; 1,04; 3,73), índice de masa corporal (IMC) ≥ 30 kg/m2 (RR 3,23; 2,02; 5,15) y circunferencia de cintura alterada (RR 1,61; 1,13;2,29), mientras el HT se asoció con sexo masculino (RR 15,18; 8,92;25,81), IMC ≥ 30 kg/m2 (RR 3,68; 2,23;6,06), circunferencia de cintura alterada (RR 2,68; 1,77;4,05) y glicemia elevada (RR 2,55; 1,27;5,10), pero no con estatura al nacer. CONCLUSIONES: Las prevalencias de PAL y HT entre los adultos jóvenes de la cohorte fueron mayores en hombres que en mujeres. Mayor estatura al nacer fue asociado con PAL, pero no con HT, mientras que el peso al nacer no estuvo asociado con PAL o HT. Factores de riesgo de adulto explicaron la mayoría de los aumentos de PAL o HT.

Weather parameters and nosocomial bloodstream infection: a case-referent study

OBJECTIVE To evaluate if temperature and humidity influenced the etiology of bloodstream infections in a hospital from 2005 to 2010.METHODS The study had a case-referent design. Individual cases of bloodstream infections caused by specific groups or pathogens were compared with several references. In the first analysis, average temperature and humidity values for the seven days preceding collection of blood cultures were compared with an overall “seven-days moving average” for the study period. The second analysis included only patients with bloodstream infections. Several logistic regression models were used to compare different pathogens and groups with respect to the immediate weather parameters, adjusting for demographics, time, and unit of admission.RESULTS Higher temperatures and humidity were related to the recovery of bacteria as a whole (versus fungi) and of gram-negative bacilli. In the multivariable models, temperature was positively associated with the recovery of gram-negative bacilli (OR = 1.14; 95%CI 1.10;1.19) or Acinetobacter baumannii (OR = 1.26; 95%CI 1.16;1.37), even after adjustment for demographic and admission data. An inverse association was identified for humidity.CONCLUSIONS The study documented the impact of temperature and humidity on the incidence and etiology of bloodstream infections. The results correspond with those from ecological studies, indicating a higher incidence of gram-negative bacilli during warm seasons. These findings should guide policies directed at preventing and controlling healthcare-associated infections.

Interrelation between parasitic infections and hypovitaminosis A: Schistosoma mansoni infection and the retinol blood levels in an endemic area of State of Minas Gerais (Brazil)

The interrelation between schistosomiasis and the retinol blood levels was studied in a double blind method, by comparing the serum vitamin A of the infected and non-infected group of an endemic area of Schistosoma mansoni infection. The infected group was characterized by 106 parasitized persons in the intestinal and hepatointestinal forms, who eliminated less than 500 eggs/gram of feces (Modified Kato's method); the non-infected group was characterized by 112 inhabitants of this endemic area without eggs in the stools and presenting negative intradermal reactions, and absence of previous specific treatment. The blood levels of retinol was determinated using trifluoracetic acid method, regarding the normal levels > 20,0mg/100ml. The results of this study point out the absence of correlation between S. mansoni infection and blood levels of vitamin A.

Potential infectivity of blood from HBsAG asymptomatic carriers due to the presence of HBV-DNA and comparison with other markers of hbv infection

Serum samples from 356 HBsAg positive asymptomatic carriers, which were titrated by reverse passive hemagglutination, were analysed for the presence of HBV-DNA, HBsAg and IgM anti-HBc. The samples were divided in three classes, according to the titers of HBsAg and IgM anti-HBc and the distribution of HBV-DNA and HBsAg among these classes was studied. In the high titer class of HBsAg, 65% of samples have one or both markers against only 19% in the low titer class. From the total of 356 samples, 121 gave positive results for IgM anti-HBc (33.9%). From these, 38.9% of HBV-DNA and 47.9% of HBeAg were observed, whereas in samples with absence of IgM anti-HBc, 18.3% and 16.6% were respectively found. A higher frequency of agreement between all these markers was found in the class of high titers of HBsAg; however, HBV-DNA was detected in the low titer class of HBsAg and little or no IgM anti-HBc, showing potential blood infectivity even in HBsAg positive borderline samples.

Trends of T. cruzi infection based on data from blood bank screening

Between October 1988 and April 1989 a cross-sectional survey was carried out in six out of eight blood banks of Goiânia, Central Brazil. Subjects attending for first-time blood donation in the mornings of the study period (n = 1358) were interviewed and screened for T. cruzi infection as a part of a major study among blood donors. Tests to anti-T. cruzi antibodies were performed, simultaneously, by indirect hem agglutination test (IHA) and complement fixation test (CFT). A subject was considered seropositive when any one of the two tests showed a positive result. Information on age, sex, place of birth, migration and socio-economic level was recorded. Results from this survey were compared with seroprevalence rates obtained in previous studies in an attempt to analyse trend of T. cruzi infection in an endemic urban area. The overall seroprevalence of T. cruzi infection among first-time donors was found to be 3.5% (95% confidence interval 2.5%-4.5% ). The seroprevalence rate increased with age up to 45 years and then decreased. Migrants from rural areas had higher seroprevalence rates than subjects from urban counties (1.8%-16.2% vs. 0%-3.6%). A four fold decrease in prevalence rates was observed when these rates were compared with those of fifteen years ago. Two possible hypotheses to explain this difference were suggested: 1. a cohort effect related with the decrease of transmission in rural areas and/or 2. a differential proportion of people of rural origin among blood donors between the two periods. The potential usefulness of blood banks as a source of epidemiological information to monitor trends of T. cruzi infection in an urban adult population was stressed.