Settleable atmospheric particulate matter affects the swimming performance and aerobic metabolic rate of Nile tilapia (Oreochromis niloticus).

Atmospheric particulate matter (APM) produced by the steel industry comprises a complex mixture of particles that includes a wide variety of metals and metallic nanoparticles. These particles settle out onto areas surrounding the industries. There is evidence that this 'settleable' APM (SePM) may cause air-to-water cross-contamination with significant effects on aquatic biota. Recent investigations have reported sublethal impacts on the gill structure and blood oxygen-carrying capacity of fishes, which raises the hypothesis that there will be consequences for gas exchange capacity and ability to support aerobic activities. Therefore, we investigated the effects of an environmentally relevant level of SePM contamination on swimming performance and associated aerobic metabolic rates in Nile tilapia, Oreochromis niloticus. Short-term exposure (96 h) to SePM reduced critical swimming speed, energetic efficiency of aerobic swimming, standard metabolic rate, maximum metabolic rate, and aerobic scope. The compromised swimming performance could have adverse ecological effects by limiting foraging ability, predator evasion, territorial protection, and migration. The impairments to aerobic capacity could also affect overall fish performance by influencing long-term energy balance and allocation to growth and reproduction. Thus, despite being sublethal, SePM contamination is considerably debilitating, and if its limiting effects are not compensated for in the longer term, this may reduce the survival and fitness of fish populations.

Settleable atmospheric particulate matter affects cardiorespiratory responses to hypoxia in Nile tilapia (Oreochromis niloticus).

Atmospheric particulate matter (APM) emitted by iron ore processing industries has a complex composition, including diverse metallic particles and nanoparticles. Settleable APM (SePM) causes air to water cross-contamination and has recently been demonstrated to have harmful sublethal impacts on fish, eliciting stress responses, affecting the immune system, and reducing blood oxygen-carrying capacity. These findings imply potential consequences for fish aerobic performance and energy allocation, particularly in their ability to tolerate respiratory challenges such as aquatic hypoxia. To assess that potential limitation, we analyzed metabolic, cardiorespiratory, and morphological alterations after exposing tilapia, Oreochromis niloticus, to an environmentally relevant concentration of SePM (96 h) and progressive hypoxia. The contamination initiated detectable gill damage, reducing respiratory efficiency, increasing ventilatory effort, and compromising fish capacity to deal with hypoxia. Even in normoxia, the resting respiratory frequency was elevated and limited respiratory adjustments during hypoxia. SePM increased O2crit from 26 to 34% of O2 (1.84 to 2.76 mg O2·L-1). Such ventilatory inefficacy implies higher ventilatory cost with relevant alterations in energy allocation. Progression in gill damage might be problematic and cause: infection, blood loss, ion imbalance, and limited cardiorespiratory performance. The contamination did not cause immediate lethality but may threaten fish populations due to limitations in physiological performance. This was the first investigation to evaluate the physiological responses of fish to hypoxia after SePM contamination. We suggest that the present level of environmental SePM deserves attention. The present results demonstrate the need for comprehensive studies on SePM effects in aquatic fauna.

Analysis of Mendelian inheritance and genetic linkage in microsatellite loci of Eucalyptus urophylla S.T. Blake.

Eucalyptus urophylla is an important species in the Brazilian forest sector due to its rapid growth rates and resistance to disease. The aim of this study was to verify Mendelian inheritance, genetic linkage, and genotypic disequilibrium for 15 microsatellite loci, with the goal of producing a robust set of genetic markers. Mendelian inheritance and genetic linkage analyses were carried out using genotypes from maternal trees, and their open-pollinated seeds and genotypic disequilibrium were assessed using adult trees. By comparing heterozygous maternal genotypes and their seeds, we found no significant deviations from the expected 1:1 Mendelian segregation and the expected 1:1:1:1 segregation hypothesis for pairwise loci. For adult trees, we did not find strong evidence of genotypic imbalance for pairwise loci. Our results indicated that the analyzed set of microsatellite loci could be used to carry out analyses of genetic diversity, mating system, and parentage in E. urophylla.

Pain-autonomic interaction after work-induced sleep restriction.

BACKGROUND AND PURPOSE: Poor sleep is commonly associated with alterations in pain perception. However, there is a lack of studies that address work-associated sleep restriction (SR) and changes in non-nociceptive perception and autonomic responses after work-induced SR. METHODS: This study was performed with 19 medical students after a normal-sleep night (NS phase) and after a night shift at the local emergency room (SR phase). We performed clinical assessment, quantitative sensory testing for electrical and temperature sensation, RR interval analysis, and recorded sudomotor skin responses (SSRs). RESULTS: The total mean duration of sleep was 436 ± 18 min in the NS group and 120 ± 28 min in the SR group (P<0.001). The anxiety scores were higher following the SR phase compared with those after the NS phase (P<0.01). After SR, there was a decrease in heat-pain threshold, but neither warm nor electrical thresholds were affected. Following SR, subjects showed higher SSR amplitudes and an increased number of double responses at an interstimulus interval of 2 s. We also observed a moderate inverse correlation between heat-pain thresholds and SSR amplitude (r= -0.46; P<0.01). However, there was no correlation between anxiety scores and SSR parameters. CONCLUSIONS: The effects of SR in the context of work stress on pain are specific and appear unrelated to general changes in sensory perception. Hyperalgesia was associated with abnormal autonomic responses, but not with increased anxiety, which suggests an association between the nociceptive and autonomic nervous systems that is independent of the emotional state.

Neonatal morphine administration leads to changes in hippocampal BDNF levels and antioxidant enzyme activity in the adult life of rats.

It is know that repeated exposure to opiates impairs spatial learning and memory and that the hippocampus has important neuromodulatory effects after drug exposure and withdrawal symptoms. Thus, the aim of this investigation was to assess hippocampal levels of BDNF, oxidative stress markers associated with cell viability, and TNF-α in the short, medium and long term after repeated morphine treatment in early life. Newborn male Wistar rats received subcutaneous injections of morphine (morphine group) or saline (control group), 5 µg in the mid-scapular area, starting on postnatal day 8 (P8), once daily for 7 days, and neurochemical parameters were assessed in the hippocampus on postnatal days 16 (P16), 30 (P30), and 60 (P60). For the first time, we observed that morphine treatment in early life modulates BDNF levels in the medium and long term and also modulates superoxide dismutase activity in the long term. In addition, it was observed effect of treatment and age in TNF-α levels, and no effects in lactate dehydrogenase levels, or cell viability. These findings show that repeated morphine treatment in the neonatal period can lead to long-lasting neurochemical changes in the hippocampus of male rats, and indicate the importance of cellular and intracellular adaptations in the hippocampus after early-life opioid exposure to tolerance, withdrawal and addiction.

Clinical and biochemical study of 28 patients with mucopolysaccharidosis type VI.

This paper presents data collected by a Brazilian center in a multinational multicenter observational study of patients with mucopolysaccharidosis type VI (MPS VI), aiming at determining the epidemiological, clinical, and biochemical profile of these patients. Twenty-eight south-American patients with MPS VI were evaluated through medical interview, physical exam, echocardiogram, electrocardiogram, ophthalmologic evaluation, quantification of glycosaminoglycans (GAGs) in urine, and measurement of the activity of N-acetylgalactosamine-4-sulfatase (ARSB) in leukocytes. 92.9% of patients were Brazilian. Mean age at diagnosis and at evaluation was 48.4 months and 97.1 months, respectively. 88% of patients had onset of symptomatology before the age of 36 months. Consanguinity was reported by 27% of the families. Mean weight and height at birth were 3.481 kg and 51.3 cm, respectively. The most frequently reported clinical manifestations were short stature, corneal clouding, coarse facial features, joint contractures, and claw hands. All patients presented with echocardiogram changes as well as corneal clouding. Mean ARSB activity in leukocytes was 5.4 nmoles/h/mg protein (reference values: 72-174), and urinary excretion of GAGs was on average 7.9 times higher than normal. The number of clinical manifestations did not show a significant correlation with the levels of urinary GAGs nor with the ARSB activity. Also, no significant correlation was found between the levels of urinary GAGs and the ARSB activity. It was concluded that MPS VI has high morbidity and that, when compared with data published in the literature, patients in our study were diagnosed later and presented with a higher frequency of cardiological findings.

An Mn2+-stimulated neutral-sphingomyelinase in seminiferous tubules of immature Wistar rats.

Mammalian sphingomyelinases have been implicated in many important physiological and pathophysiological processes. The seminiferous tubules of immature (19 day-old) Wistar rats have at least three types of sphingomyelinases, a lysosomal one and two microsomal ones. One of the microsomal sphingomyelinases is active at pH 6.5 and is stimulated by Mn2+ > Co2+ > Mg2+, and the other is active at pH 7.4 and is stimulated by Mn2+ > Mg2+ and inhibited by Co2+. The two microsomal enzymes are only slightly inhibited by EDTA and at pH 7.4 the stimulatory effects of Mn2+ and Mg2+ are additive. These data characterize the existence of two different membrane-bound sphingomyelinases in the seminiferous tubules of the rat.

Selective surveillance for nosocomial infections in a Brazilian hospital.

OBJECTIVE: To devise a system for surveying the frequency of nosocomial infections in a tertiary care hospital in a developing country. DESIGN: Prospective selective surveillance by nurses of the charts of patients at high risk for nosocomial infections, as identified by a form completed by resident physicians. The sensitivity, specificity, and predictive value of this method of selective surveillance were compared with those for total prospective chart review by two infectious disease specialists. SETTING: A university hospital in northeastern Brazil. PATIENTS: All patients hospitalized for more than 72 hours with an identified risk factor for nosocomial infection. RESULTS: The ratio of nosocomial infections to 100 discharges was 13.4 and the incidence density was 11.2/1,000 patient days. The surveillance method demonstrated a sensitivity of 74% and a specificity of 99.7%. Positive predictive value was 93%, negative predictive value was 99%, and overall accuracy was 98%. CONCLUSIONS: This method of selective surveillance for nosocomial infections based on risk factors identified by physicians demonstrated excellent predictive value and overall accuracy and may be of use to other hospitals that lack a nursing care plan book such as the Kardex. The relative frequency of nosocomial infections significantly exceeded the rates reported from hospitals in developed countries.

Infecção perinatal pelo citomegalovirus em hospital publico do municipio de Sao Paulo: estudo prospectivo / Perinatal infection due to cytomegaloviruses in a public hospital of the municipality of Säo Paulo: a prospective study

Com o objetivo de se avaliar a magnitude da infeccao perinatal pelo citomegalovirus em hospital publico do municipio de Sao Paulo, os autores acompanharam prospectivamente 98 recem-nascidos ete o quarto mes de vida. Amostras de urina foram coletadas ao nascimento e posteriormente a cada mes, para inoculacao em tubos contendo fibroblastos humanos. Amostras de sangue foram coletadas ao nascimento, no segundo e quarto mes de vida para pesquisa de anticorpos IgM especificos para o CMV, pelo metodo de imunofluorescencia indireta. Dos 37 recem-nascidos que foram acompanhados ate o quarto mes de vida, 9 se infectaram neste periodo, com diagnostico feito pelo isolamento do CMV. O risco de aquisicao da infeccao pelo citomegalovirus no periodo perinatal estimado pela tabua de sobrevivencia foi de 30,9 por cento. A pesquisa de anticorpos IgM por imunofluorescencia so permitiu tal diagnostico em 2 casos (8,1 por cento). A diferenca observada entre os dois metodos foi estatisticamente significante (p = 0,015). O estudo da prevalencia de anticorpos IgG pelo ensaio imunoenzimatico nas maes das criancas mostrou taxas de 92,7 por cento. Nao se isolou CMV nas amostras de leite materno, coletadas mensalmente ate o terceiro mes de lactacao...

[Perinatal infection due to cytomegaloviruses in a public hospital of the municipality of São Paulo: a prospective study]. / Infecção perinatal pelo citomegalovírus em hospital público do município de São Paulo: estudo prospectivo.

In order to demonstrate the occurrence of CMV perinatal infection in a middle socioeconomic class population, the authors conducted a 8-month prospective study in 37 children, not infected congenitally, born in a public hospital of São Paulo city, Prevalence of CMV-IgG antibodies in mothers, detected by immunoenzymatic assay (ELISA), was 92.7%. Survival analysis showed that the risk of acquiring CMV perinatal infection diagnosed by virus isolation in human fibroblasts was 30.9%. When the diagnostic method was detection of IgM class antibodies by indirect immunofluorescence the risk was 8.1% (p < 0.05). Milk samples inoculated in human fibroblasts failed to demonstrate the presence of virus. The infected children did not present any signal of disease in a 4-month follow-up.

Avaliacao de um servico de abreugrafia dentro de um hospital universitario Aspectos preventivos de educacao medica. / Evaluation of a fluoroscopic service in an university hospital - Preventive aspects of medical education

Os autores avaliam a eficacia de um servico de abreugrafia dentro de um hospital universitario (HC-FMRP-USP) analisando os beneficios resultantes para os pacientes que se submeteram ao exame abreugrafico. Estudam qual e o grau de preocupacao por parte do medico na utilizacao de exames complementares na assistencia medica. Efetuaram a revisao de 10.444 prontuarios medicos de pacientes abreugrafados no periodo setembro/1967 a setembro/1970.Apresentam a prevalencia das anormalidades radiologicas encontradas, numero de pacientes nos quais foi surgida feitura de exames complementares (decorrentes dos achados abreugraficos), porcentagem de casos e tempo medio em que a sugestao foi atendida, bem como a percentagem de pacientes beneficiados pelo fato de terem se submetido ao exame abreugrafico. Discutem aspectos da educacao medica envolvida na utilizacao de exames complementares, como e o caso da abreugrafia, dentro de um hospital universitario. Reafirmam o valor da mesma mostrando sua eficacia e eficiencia como processo de "screenning" para doencas dos sistemas cardiorespiratorio e osteo-muscular