Studies on entomological monitoring: mosquito species frequency in riverine habitats of the Igarapava Dam, Southern Region, Brazil

Diversity of mosquito species was evaluated in different habitats before and after the Igarapava reservoir flooding in the Grande River, Southern Cerrado of Brazil. We aimed at verifying changes in these mosquito populations in consequence of the lake formation. Four habitats were selected as sampling stations: peridomiciliary habitat, pasture, "veredas" and gallery forest patch. Bimonthly collections were made with the Shannon trap and human bait, including diurnal, crepuscular and nocturnal period of mosquito activity. The Shannon Index results from the potential vectors were compared using Student t-test. Aedes scapularis, Anopheles darlingi and An. albitarsis senso latu seasonal abundance were described with moving average and compared using chi2 test. There were changes in the mosquito frequency in the habitats, except for the "veredas" that was 13 km away from the catchment area. The altering in mosquito species seasonal abundance suggests breeding places expansion. Diversity indexes can be used to monitor changes in mosquito vector population in environments where abrupt disturbance can alter disease transmission cycles.     

Late incidence and determinants of stroke after aortic and mitral valve replacement

Background

Stroke is a devastating complication in patients with prosthetic valves, but characterization of its late occurrence from a large cohort is lacking.

Methods

Three thousand one hundred eighty-nine adult patients who underwent a total of 3,576 operations for left-heart valve replacement were managed with contemporary anticoagulation guidelines and prospectively followed in a dedicated clinic. Total follow-up was 20,096 patient years. Bootstrapped survival analysis was used to determine the impact of patient and valve related factors on the incidence of stroke.

Results

Most strokes were embolic. Linearized embolic stroke rates were 1.3% ± 0.2% per year for aortic bioprostheses, 1.4% ± 0.2% per year for aortic mechanical valves, 1.3% ± 0.3% per year for mitral bioprostheses, and 2.3% ± 0.4% per year for mitral mechanical valves (p = 0.002, vs other implant types). Age more than 75 years, female gender, and smoking were independent risk factors after aortic and mitral valve replacement. Atrial fibrillation, coronary disease, and tilting-disc mechanical prostheses were independent predictors of embolic stroke after aortic valve replacement. Preoperative left ventricular (LV) dysfunction was an independent risk factor in patients with mitral prostheses. Primary operative indication, diabetes, redo status, or the presence of two prosthetic valves were not associated with an increased hazard. The addition of acetyl salicylic or dipyridamole to warfarin anticoagulation did not significantly lower embolic stroke risk in patients with mechanical prostheses.

Conclusions

Approximately 20% of patients with valve prostheses have an embolic stroke by 15 years after valve replacement. Some risk factors such as the avoidance of smoking, mitral mechanical prostheses, aortic tilting-disc valves, and proceeding to mitral surgery before LV dysfunction occurs are potentially modifiable.     

Coronary artery calcification and aortic pulse wave velocity in chronic kidney disease patients

BACKGROUND: Patients with end-stage renal disease (ESRD) are at increased risk of cardiovascular mortality and morbidity. Many complications arise in ESRD patients as a result of the twin arterial pathologies of atherosclerosis and arteriosclerosis. Part of this latter process is calcification of the arterial media, which is thought significantly to increase vascular stiffness. The aim of our study was to explore the relationship between measures of arterial stiffness-pulse wave velocity (PWV)-and the extent of calcification in the coronary arteries (CAC). METHODS: Over a period of 2 years 82 patients from our renal unit were invited to participate in our study. Sixty-two patients agreed to undergo electron beam computerized tomography (EBCT), and in 55 (38 males and 17 females), PWV measurements were made. EBCT and PWV measurements were done according to previously described protocols. RESULTS: The mean age of the 55 patients was 56.4 years. The mean duration of dialysis was 65.4 months, and the mean CAC score was 2551. The mean PWV was 9.13 m/s. PWV strongly correlated with total CAC even after correction for age, dialysis duration, and time averaged C-reactive protein (CRP) (P= 0.0001). CAC scores were significantly different when compared according to PWV tertiles (P= 0.0001). CONCLUSION: We have demonstrated that PWV is strongly related to the degree of EBCT-derived coronary artery calcium score in chronic kidney disease patients.     

Lateral shelf acetabuloplasty in the early stage of Legg-Calvé-Perthes disease with special emphasis on the remaining growth of the acetabulum: a preliminary report

This study reports on the preliminary results in 43 patients with an early stage of unilateral Legg-Calvé-Perthes disease, treated with a shelf acetabuloplasty. The mean postoperative follow-up was 3.7 years (1.3-6.2 years). The results suggest an improved outcome in children older than 5 years of age at onset. According to the Stulberg classification, 16 hips were classified as Stulberg 2, 19 hips as Stulberg 3 and eight hips as Stulberg 4. The acetabular size, which is a measurement of the length of the acetabulum relative to the size of the shelf, increased from 48.86 to 69.13%. This reflects an incorporation of the shelf-graft into the pelvis as a result of continued growth of the lateral acetabular structures. The coverage of the femoral head by the bony acetabulum increased from 68.51 to 73.83%. The acetabular cover increases in children younger than 8 years of age and decreases in patients older than 8 years. We suggest that shelf acetabuloplasty can be considered as an appropriate surgical treatment for children older than 5 years of age, with severe Legg-Calvé-Perthes disease.     

Are lethal audiogenic seizures a missing link to the sudden infant death syndrome?

The pathogenesis of human seizure disorders has largely been derived from rodent models. A number of rodent and chick strains exhibit a genetic predisposition for lethal audiogenic seizures (AGSs) in the first year of life. Consideration is warranted that this disorder may be linked to the sudden infant death syndrome (SIDS). Factors that carry a strong association with SIDS such as hyperthermia and the prone sleeping position would conceivably play a significant role in a human AGS syndrome. Importantly, there is data to support the likelihood that motor seizure activity may be absent in infants with an AGS syndrome. Rodent AGSs may hold important clues to unraveling the mystery of SIDS.     

Psychoactive drug use in school age adolescents, Brazil

To quantify psychoactive drug use and investigate use-related variables among students of Assis, Brazil, a questionnaire was administered to collect sociodemographic data and identify the pattern of non-medical use of psychoactive drugs in 20% of public and private school students. The largest consumption indexes for lifetime use were seen for alcohol (68.9%) and tobacco (22.7%). Drugs most often used were: solvents (10.0%); marijuana (6.6%); benzodiazepines (3.8%); amphetamines (2.6%); cocaine (1.6%); and anticholinergics (1.0%).     

Investigation into the effect of household triatomine infestation on awareness among inhabitants of settlements and re-settlements in areas infested with Triatoma sordida in São Paulo State, Brazil

This study aims to analyze the effect of domiciliary infestation by triatomine bugs on the degree to which inhabitants are aware of potential vector transmission of Chagas disease. Such recently constructed dwellings comprise housing groups classified as settlements and re-settlements, selected respectively in the municipalities of Euclides da Cunha Paulista and Paulicéia, S?o Paulo State, Brazil. Both municipalities are under the jurisdiction of the Presidente Prudente Health Administrative Region. Of the 319 residents, some 100 (76.0% of whom were re-settlement residents) knew about triatomine bugs. Housing units infested with triatomines were inhabited by 93 people. In 79.2% of the infested houses, 26.8% of the residents knew about Chagas disease and its vectors, but in 50.0% of the households, some people did not know what to do in case of triatomine infestation. Population samples from settlements and re-settlements, regardless of sex, age, and the State of origin, showed no difference in attitudes towards the prevention of Chagas disease or knowledge of the disease vector.     

Ocular manifestations in Dengue fever

PURPOSE: To report a case of Dengue fever resulting in permanent visual loss in both eyes due to retinal capillary occlusion. METHODS: Case report. RESULTS: Severe permanent visual loss occurred in a patient with Dengue fever. Dilated fundus exam showed vascular sheathing with associated retinal hemorrhages at the equator and cotton wool spots in the maculae of both eyes. Fluorescein angiography revealed areas of capillary nonperfusion at the equator and in the macula. The diagnosis of Dengue fever was confirmed by serology detecting IgM antibodies to the Dengue virus. CONCLUSION: Ocular abnormalities may be seen in patients with Dengue fever, therefore ophthalmoscopy should be performed in patients presenting with severe forms of the disease.     

Simultaneous repair of myelomeningocele and shunt insertion

Methods Simultaneous shunt placement and neural tube repair are described and compared with a concomitant series of patients with delayed shunting. Twenty-eight patients with a myelomeningocele underwent closure of neural tube defects at our Institution from 1998 to 2001. Eleven patients (Group 1) had concomitant surgery performed after birth. Group 2 (7 out of 28) included patients without hydrocephalus at birth, in Group 3 (4 out of 28) the children did not develop hydrocephalus, and Group 4 (6 out of 28) patients were born outside our hospital and referred for surgical care after birth.Discussion Simultaneous insertion of shunt and correction of a myelomeningocele do not pose an additional risk to the child and do have some advantages, facilitating healing of the back without CSF leakage and protecting the brain from the effects of progressive ventricular dilatation. Patients with a myelomeningocele born outside the hospital are prone to infectious complications.