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1.
Appl Radiat Isot ; 202: 111037, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37782981

RÉSUMÉ

The Thermoluminescent dosimeter is a solid material used as instrumentation for environmental monitoring through determining environmental equivalent dose H∗(10). This work presents the calibration methodology for TLDs LiF:Mg, Cu, P dosimeters and their application to measure H∗(10) in internal buildings occupied by inhabitants of an urban area. The calibration factor and type tests were made according to ISO 4037-3 and IEC 62387, and the uncertainty was determined. The values found are under the reference values. Therefore, the dosimeters can be applied.

2.
Int J Mol Sci ; 24(16)2023 Aug 18.
Article de Anglais | MEDLINE | ID: mdl-37629124

RÉSUMÉ

Turbot aquaculture production is an important economic activity in several countries around the world; nonetheless, the incidence of diseases, such furunculosis, caused by the etiological agent A. salmonicida subsp. salmonicida, is responsible for important losses to this industry worldwide. Given this perspective, this study aimed to evaluate early immune responses in turbot (S. maximus L.) following infection with A. salmonicida subsp. salmonicida. For this, 72 fish were individually weighed and randomly distributed into 6 tanks in a circulating seawater system. For the bacterial challenge, half of the individuals (3 tanks with 36 individuals) were infected using a peritoneal injection with the bacterial suspension, while the other half of individuals were injected with PBS and kept as a control group. Several factors linked to the innate immune response were studied, including not only haematological (white blood cells, red blood cells, haematocrit, haemoglobin, mean corpuscular volume, mean cell haemoglobin, mean corpuscular haemoglobin concentration, neutrophils, monocytes, lymphocytes, thrombocytes) and oxidative stress parameters, but also the analyses of the expression of 13 key immune-related genes (tnf-α, il-1ß, il-8, pparα-1, acox1, tgf-ß1, nf-kB p65, srebp-1, il-10, c3, cpt1a, pcna, il-22). No significant differences were recorded in blood or innate humoral parameters (lysozyme, anti-protease, peroxidase) at the selected sampling points. There was neither any evidence of significant changes in the activity levels of the oxidative stress indicators (catalase, glutathione S-transferase, lipid peroxidation, superoxide dismutase). In contrast, pro-inflammatory (tnf-α, il-1ß), anti-inflammatory (il-10), and innate immune-related genes (c3) were up-regulated, while another gene linked with the lipid metabolism (acox1) was down-regulated. The results showed new insights about early responses of turbot following infection with A. salmonicida subsp. salmonicida.


Sujet(s)
Poissons plats , Animaux , Immunité innée , Interleukine-10 , Facteur de nécrose tumorale alpha
3.
Foods ; 12(9)2023 Apr 27.
Article de Anglais | MEDLINE | ID: mdl-37174348

RÉSUMÉ

Seaweeds are a sustainable source of protein and lipids that may be used to replace fish by-products in aquaculture feed. This study aimed at using the macroalgae Pelvetia canaliculata as an ingredient in gilthead seabream (Sparus aurata) feed, either as freeze-dried powder or as algae residue (waste) that was obtained after the supplementation of sunflower oil. The formulated diets and the fish muscle were analyzed concerning the proximate composition and the fatty acid profile. The health lipid indices hypocholesterolemic/hypercholesterolemic (h/H), atherogenic (AI), thrombogenic (TI), as well as n-3/n-6 and polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) ratios were calculated. Additionally, the peroxidizability index (PI) was determined. No differences were observed in the proximate composition of fish muscle regardless of the diet used. Fish fed a diet supplemented with 10% of algae waste (W10) stand out for the highest content in oleic acid (C18:1 n-9), and the lowest in both linoleic (C18:2 n-6) and palmitic (C16:0) fatty acids. All fish samples showed values of health lipid indices within the limits recommend for a nutritional balanced diet. These results highlight that fish fed diets supplemented with P. canaliculata are sources of healthy lipids that might be consumed on a regular basis to prevent cardiovascular diseases.

4.
Sci Rep ; 12(1): 14836, 2022 09 01.
Article de Anglais | MEDLINE | ID: mdl-36050345

RÉSUMÉ

Seaweeds are an important source of nutrients and bioactive compounds and have a high potential as health boosters in aquaculture. This study evaluated the effect of dietary inclusion of Gracilaria gracilis biomass or its extract on the European seabass (Dicentrarchus labrax) gut microbial community. Juvenile fish were fed a commercial-like diet with 2.5% or 5% seaweed biomass or 0.35% seaweed extract for 47 days. The gut microbiome was assessed by 16S rRNA amplicon sequencing, and its diversity was not altered by the seaweed supplementation. However, a reduction in Proteobacteria abundance was observed. Random forest analysis highlighted the genera Photobacterium, Staphylococcus, Acinetobacter, Micrococcus and Sphingomonas, and their abundances were reduced when fish were fed diets with algae. SparCC correlation network analysis suggested several mutualistic and other antagonistic relationships that could be related to the predicted altered functions. These pathways were mainly related to the metabolism and biosynthesis of protective compounds such as ectoine and were upregulated in fish fed diets supplemented with algae. This study shows the beneficial potential of Gracilaria as a functional ingredient through the modulation of the complex microbial network towards fish health improvement.


Sujet(s)
Serran , Microbiome gastro-intestinal , Gracilaria , Aliment pour animaux/analyse , Animaux , Serran/métabolisme , Régime alimentaire , Extraits de plantes/métabolisme , ARN ribosomique 16S/génétique , ARN ribosomique 16S/métabolisme
5.
Appl Radiat Isot ; 186: 110217, 2022 Aug.
Article de Anglais | MEDLINE | ID: mdl-35594698

RÉSUMÉ

Radon and its progeny are the major cause of natural radiation emission and its activity concentration is measured by alpha detectors, such as Solid-State Nuclear Track Detector (SSNTD). This work aims to present the applications of CR-39-type SSNTD according to the Natural Radiation Laboratory (LRN) and reports in the literature, aiming to ensure the radioprotection of public and occupationally exposed individuals in indoor and outdoor environments. Therefore, it was reinforced that CR-39 is an important detector for radon radioprotection and dosimetry.


Sujet(s)
Polluants atmosphériques radioactifs , Pollution de l'air intérieur , Contrôle des radiations , Radon , Polluants atmosphériques radioactifs/analyse , Pollution de l'air intérieur/analyse , Humains , Contrôle des radiations/méthodes , Radiométrie/méthodes , Radon/analyse , Produits de filiation du radon/analyse
6.
Int J Mol Sci ; 23(6)2022 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-35328519

RÉSUMÉ

Currently, aquaculture production of rainbow trout (Oncorhynchus mykiss) is a multibillion dollar industry; nevertheless, the development of this sector has not been exempt from pitfalls related to the recurrent presence of pathogens of bacterial origin. This is the case of Yersinia ruckeri, the etiologic agent of the infectious pathology known as Enteric Red Mouth Disease (ERM), causing serious economic losses that can be as high as 30-70% of production. Although several studies have been performed regarding pathogen features and virulence factors, more information is needed about the host defense mechanism activation after infection. Given this perspective, this study aimed to evaluate rainbow trout's short-term innate immune response against infection with Y. ruckeri. A series of factors linked to the innate immune response were evaluated, including determination of hematological parameters, oxidative stress biomarkers, and analysis of the expression of immune-related genes. Results showed a significant decrease in several hematological parameters (white blood cell count, hematocrit, neutrophils, monocytes, lymphocytes, and thrombocytes) and oxidative stress indicators (SOD) between the control and infected groups. In addition, there were significant differences in the level of gene expression between infected individuals and the control group. Most of these genes (il-1ß, il-8, il-10, tnf-α1, tnf-α2, socs3, mmp-9, cath, hsp-70, saa, fer, pcb) were upregulated within the first 24 h following infection. Results from this study showed more insights into the short-term immune response of rainbow trout to infection with Y. ruckeri, which may be useful for the establishment of biomarkers that may be used for the early detection of ERM.


Sujet(s)
Maladies des poissons , Oncorhynchus mykiss , Yersinioses , Animaux , Immunité innée , Oncorhynchus mykiss/génétique , Yersinioses/médecine vétérinaire , Yersinia ruckeri/génétique
7.
Int. j. cardiovasc. sci. (Impr.) ; 35(2): 191-201, Mar.-Apr. 2022. tab, graf
Article de Anglais | LILACS | ID: biblio-1364978

RÉSUMÉ

Abstract Background Physical Fitness Tests (PFTs) are part of military routines and are usually administered to applicants for the Brazilian corps member, including the civil police. Objective To identify in the literature, scientific articles aimed at assessing physical fitness of police and military personnel in Brazil, using PFTs. Methods This was a systematic review, using the PRISMA systematization, using the following search keywords "police", "military", "physical fitness test" and " PFT", in English and Portuguese. The databases used were ScienceDirect, PubMed, BVS (Lilacs) and Scielo. Only original works performed with police and military personnel in Brazil were selected, through the application of inclusion and exclusion criteria. Results After the screening process, 11 articles were selected from a total of 1,487. Conclusions The data collected from the selected articles suggest that older age is related to a decrease in physical fitness, and better performance in the tests is related to a lower risk of comorbidities. Although high-intensity training improves physical fitness and anthropometric data, it is associated with injury rates; physically active lifestyle is associated with better flexibility.


Sujet(s)
Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Jeune adulte , Aptitude physique , Police , Épreuve d'effort/méthodes , Personnel militaire , Poids et mesures du corps , Brésil , Exercice physique , Comorbidité , Facteurs de risque , Facteurs âges , Santé militaire , Mode de vie
8.
Int J Mol Sci ; 23(3)2022 Jan 29.
Article de Anglais | MEDLINE | ID: mdl-35163486

RÉSUMÉ

Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases.


Sujet(s)
Immunité , Photobacterium/physiologie , Dorade/immunologie , Dorade/microbiologie , Animaux , Cellules sanguines/métabolisme , Protéines de poisson/génétique , Protéines de poisson/métabolisme , Régulation de l'expression des gènes , Rein céphalique/métabolisme , Immunité humorale/génétique , Immunité innée/génétique , Stress oxydatif/génétique , Dorade/sang , Dorade/génétique
9.
Environ Technol ; 43(10): 1437-1445, 2022 Apr.
Article de Anglais | MEDLINE | ID: mdl-33016235

RÉSUMÉ

Sunlight-mediated disinfection in wastewater treatment ponds is widely recognised as the main role for disinfection, but pathogen removal can be limited by poor light penetration in the water column. The aim of this research is to evaluate a different and simple type of intervention for improving bacterial disinfection, by placing mid-depth transverse baffles perpendicular to the theoretical flow in an existing shallow maturation pond, aiming at increasing the opportunity for bacteria to receive radiation at the upper layers of the pond. In order to understand the hydrodynamic mechanisms and evaluate the effectiveness of the proposed intervention, a 3D Computational Fluid Dynamic (CFD) model was applied, including the transverse baffles and a particle-tracking model. This was complemented by monitoring E. coli in the pond, in the phase before and after inclusion of the transversal baffles. Overall, the transverse baffles increased disinfection efficiency by moulding/re-routing the hydrodynamic flow and increasing microorganism exposure to the sunlight.


Sujet(s)
Désinfection , Étangs , Escherichia coli , Lumière du soleil , Élimination des déchets liquides
10.
Fish Shellfish Immunol ; 119: 105-113, 2021 Dec.
Article de Anglais | MEDLINE | ID: mdl-34600116

RÉSUMÉ

Seaweeds still possess a large undisclosed potential, mainly due to their constituent's richness, which may have several uses for society. In aquaculture, they may play a role as an ecological sustainable aquafeed supplement to increase overall health and fight pathogenic outbreaks. This study aimed to evaluate the general health modulation that the inclusion of Gracilaria gracilis could accomplish in the diet of Dicentrarchus labrax. Dried algae at 2.5% and 5% and algal extract at 0.35% inclusion levels were supplemented to seabass diet to evaluate possible growth, haematological, immunological, antioxidant, metabolic, and intestinal morphological modulations. The supplementations did not impact growth or feed utilization, and barely affected the haematological profile and some metabolic parameters. Nevertheless, it caused a marked outcome on lysozyme, some oxidative stress biomarkers, and intestine morphology, suggesting beneficial consequences from the algal inclusion. Dried algae powder, with a 2.5% inclusion, boosted immune response, with higher plasmatic lysozyme and intestinal acid goblet cells and protected against oxidative damages by improved enzymatic and non-enzymatic responses. Thus, we provide evidence that dietary seaweed application may be a path towards a more sustainable aquaculture industry.


Sujet(s)
Serran , Gracilaria , Algue marine , Aliment pour animaux/analyse , Animaux , Régime alimentaire/médecine vétérinaire , Compléments alimentaires , Lysozyme
11.
Environ Res ; 195: 110808, 2021 04.
Article de Anglais | MEDLINE | ID: mdl-33513382

RÉSUMÉ

Although much has been discovered regarding the characteristics of SARS-CoV-2, its presence in aerosols and their implications in the context of the pandemic is still controversial. More research on this topic is needed to contribute to these discussions. Presented herein are the results of ongoing research to detect SARS-CoV-2 RNA in aerosol in different hospital facilities (indoor environments) and public spaces (outdoor environments) of a metropolitan center in Brazil. From May to August 2020, 62 samples were collected using active sampling method (air samplers with filters) and passive method (petri dishes) in two hospitals, with different occupancies and infrastructure for contamination control. Outdoor public spaces such as sidewalks and a bus station were also investigated. Five air samples from four facilities in a hospital tested positive for SARS-CoV-2 in suspended and sedimentable particles. SARS-CoV-2 was found in aerosols inside the Intensive Care Unit (ICU), in the protective apparel removal room, in the room containing patient mobile toilets and used clothes (room with natural ventilation) and in an external corridor adjacent to the ICU, probably coming from infected patients and/or from aerosolization of virus-laden particles on material/equipment. Our findings reinforce the hypothesis of airborne transmission of the new coronavirus, contributing to the planning of effective practices for pandemic control.


Sujet(s)
COVID-19 , SARS-CoV-2 , Aérosols , Brésil , Hôpitaux , Humains , ARN viral
12.
Arq Neuropsiquiatr ; 78(6): 361-369, 2020 06.
Article de Anglais | MEDLINE | ID: mdl-32520231

RÉSUMÉ

BACKGROUND: Active games based on virtual reality have been widely used in the rehabilitation of many clinical conditions. However, studies on the use of Xbox/Kinect are rare, and technology application in stroke treatment is not clear yet. OBJECTIVE: To verify the outcomes (O) analyzed in randomized controlled trials (C; S) that investigated the use of Xbox/Kinect (I) in patients with stroke (P). METHODS: This is a systematic literature review that meets PRISMA standards and the eligibility criteria according to the PICOS strategy. The search procedure was performed by two researchers. The research strategy was repeated in case of divergence. Effect size was calculated by Cohen's formula and Hopkins rank. The risk of individual bias was assessed using PEDro Score and Higgins Classification. RESULTS: The main outcomes were postural balance and activities of daily living, with four studies addressing these variables. However, only one study showed the effect of Xbox/Kinect intervention on balance as large, as in two other studies evaluating manual dexterity and depression, respectively. CONCLUSION: The greater use of Xbox/Kinect in treating patients after stroke is in recovery of balance and motor function, and the evidence support its application. These findings enable the use of virtual reality technology through Xbox/Kinect in rehabilitation programs, focusing on postural balance and motor skills. However, conclusive results are still not possible. Therefore, caution in the use of this technology is required.


Sujet(s)
Réadaptation après un accident vasculaire cérébral , Accident vasculaire cérébral , Jeux vidéo , Activités de la vie quotidienne , Humains , Équilibre postural/physiologie
13.
Arq. neuropsiquiatr ; 78(6): 361-369, June 2020. tab, graf
Article de Anglais | LILACS | ID: biblio-1131715

RÉSUMÉ

ABSTRACT Background: Active games based on virtual reality have been widely used in the rehabilitation of many clinical conditions. However, studies on the use of Xbox/Kinect are rare, and technology application in stroke treatment is not clear yet. Objective: To verify the outcomes (O) analyzed in randomized controlled trials (C; S) that investigated the use of Xbox/Kinect (I) in patients with stroke (P). Methods: This is a systematic literature review that meets PRISMA standards and the eligibility criteria according to the PICOS strategy. The search procedure was performed by two researchers. The research strategy was repeated in case of divergence. Effect size was calculated by Cohen's formula and Hopkins rank. The risk of individual bias was assessed using PEDro Score and Higgins Classification. Results: The main outcomes were postural balance and activities of daily living, with four studies addressing these variables. However, only one study showed the effect of Xbox/Kinect intervention on balance as large, as in two other studies evaluating manual dexterity and depression, respectively. Conclusion: The greater use of Xbox/Kinect in treating patients after stroke is in recovery of balance and motor function, and the evidence support its application. These findings enable the use of virtual reality technology through Xbox/Kinect in rehabilitation programs, focusing on postural balance and motor skills. However, conclusive results are still not possible. Therefore, caution in the use of this technology is required.


RESUMO Introdução: Jogos ativos baseados em realidade virtual têm sido amplamente utilizados na reabilitação de muitas condições clínicas. No entanto, estudos sobre a utilização do Xbox/Kinect são raros, e não está clara a aplicabilidade da tecnologia no tratamento de pacientes que tiveram acidente vascular cerebral. Objetivo: Verificar os desfechos (O) analisados em ensaios clínicos randomizados e controlados (C; S), que investigaram a utilização do Xbox/Kinect (I) em pacientes que tiveram acidente vascular cerebral (P). Métodos: Trata-se de uma revisão sistemática da literatura que atende aos padrões do PRISMA e aos critérios de elegibilidade, de acordo com a estratégia PICOS. O procedimento de busca foi realizado por dois pesquisadores e, em caso de divergência, a estratégia de busca foi repetida. O tamanho do efeito foi calculado por meio da fórmula de Cohen e da escala de Hopkins. O risco de viés individual foi analisado utilizando o escore PEDro e a classificação de Higgins. Resultados: Os principais desfechos foram o equilíbrio postural e as atividades de vida diária, com quatro estudos abordando essas variáveis. No entanto, apenas um estudo mostrou o efeito da intervenção com Xbox/Kinect sobre o equilíbrio como sendo grande, assim como em dois outros artigos que avaliaram destreza manual e depressão, respectivamente. Conclusão: A utilização mais comum do Xbox/Kinect no tratamento de pacientes que tiveram acidente vascular cerebral acontece na recuperação do equilíbrio e da função motora, e as evidências apoiam o seu uso. Esses achados permitem o uso da tecnologia de realidade virtual por meio do Xbox/Kinect em programas de reabilitação, com foco no equilíbrio postural e nas habilidades motoras. Porém, resultados conclusivos ainda não são possíveis, o que exige cautela no uso dessa tecnologia.


Sujet(s)
Humains , Jeux vidéo , Accident vasculaire cérébral , Réadaptation après un accident vasculaire cérébral , Activités de la vie quotidienne , Équilibre postural/physiologie
14.
Trop Med Int Health ; 23(11): 1269-1279, 2018 11.
Article de Anglais | MEDLINE | ID: mdl-30282110

RÉSUMÉ

OBJECTIVES: To analyze the relationship between the occurrence of dengue and ovitrap positivity and dengue egg density in two Amazonas municipalities (Brazil) in 2016. METHODS: We performed a case-control study using secondary data from the dengue fever surveillance system. Ovitraps distributed regularly in the urban area of two cities were used to monitor the presence of the vector. The relationship between egg positivity, egg density and the location of dengue cases was evaluated using two approaches as follows: (i) based on the result of the nearest neighbour ovitrap and (ii) based on the results of the set of ovitraps within the influence area of 300 m from the location of each case and control. RESULTS: During the study period, 229 confirmed cases of dengue fever were reported in Tabatinga and 89 cases in Itacoatiara. In this study, we found that the positivity of ovitraps was related to the occurrence of dengue in Tabatinga and Itacoatiara. An association between egg density of Ae. aegypti and dengue occurrence was also observed in Itacoatiara. The temporal lags for ovitrap positivity measurements were predominantly 15 or 30 days. A dengue association for egg density for a 15-day time lag was detected for one of the case-control approaches. CONCLUSIONS: The location of dengue cases is related to ovitrap egg positivity, while a less evident possible association may exist for egg density. This indicates that these traps could be used to improve vector control actions.


Sujet(s)
Aedes/croissance et développement , Virus de la dengue/isolement et purification , Dengue/épidémiologie , Vecteurs moustiques/croissance et développement , Ovule/croissance et développement , Animaux , Brésil/épidémiologie , Études cas-témoins , Humains , Surveillance de la population
15.
PLoS Negl Trop Dis ; 12(7): e0006594, 2018 07.
Article de Anglais | MEDLINE | ID: mdl-30011278

RÉSUMÉ

BACKGROUND: Arboviruses are viruses transmitted to humans and other animals by the bite of hematophagous arthropods. Infections caused by chikungunya virus (CHIKV), dengue virus (DENV), Zika virus (ZIKV), and the deadlier yellow fever virus (YFV) are current public health problems in several countries, mainly those located in tropical and subtropical regions. One of the main prevention strategies continues to be vector control, with the elimination of breeding sites and surveillance of infested areas. The use of ovitraps for Aedes mosquitos monitoring has already demonstrated promising results, and maybe be also useful for arboviral surveillance. METHODS: This work aimed to detect natural vertical transmission of arboviruses in Aedes aegypti and Aedes albopictus. Mosquito egg collection was carried out using ovitraps in Itacoatiara, a mid-size city in Amazonas state, Brazil. Collected eggs were allowed to hatch and larvae were tested for CHIKV, DENV, and ZIKV RNA by RT-qPCR. RESULTS: A total of 2,057 specimens (1,793 Ae. aegypti and 264 Ae. albopictus), in 154 larvae pools were processed. Results showed one positive pool for CHIKV and one positive pool for ZIKV. The active ZIKV infection was further confirmed by the detection of the negative-strand viral RNA and nucleotide sequencing which confirmed the Asian genotype. The Infection Rate per 1,000 mosquitoes tested was assessed by Maximum Likelihood Estimation (MLE) with 0.45 and 0.44 for CHIKV and ZIKV, respectively, and by Minimum Infection Rate (MIR) with 0.45 for both viruses. CONCLUSION: To our knowledge, this is the first detection of ZIKV in natural vertical transmission in the Ae. aegypti, a fact that may contribute to ZIKV maintenance in nature during epidemics periods. Furthermore, our results highlight that the use of ovitraps and the molecular detection of arbovirus may contribute to health surveillance, directing the efforts to more efficient transmission blockade.


Sujet(s)
Aedes/virologie , Vecteurs moustiques/virologie , Ovule/virologie , Infection par le virus Zika/transmission , Virus Zika/isolement et purification , Aedes/physiologie , Animaux , Arbovirus/génétique , Arbovirus/isolement et purification , Arbovirus/physiologie , Brésil , Femelle , Larve/croissance et développement , Larve/physiologie , Larve/virologie , Mâle , Vecteurs moustiques/croissance et développement , Vecteurs moustiques/physiologie , Ovule/croissance et développement , Virus Zika/génétique , Virus Zika/physiologie , Infection par le virus Zika/virologie
16.
BMC Public Health ; 18(1): 356, 2018 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-29544456

RÉSUMÉ

BACKGROUND: Dengue is the most prevalent arboviral disease affecting humans. The frequency and magnitude of dengue epidemic have significantly increased over recent decades. This study aimed to identify dengue epidemic types and risk factors for the extensive epidemics that occurred in 2010-2011, across the municipalities of Amazonas state, Brazil. METHODS: Using an ecological approach, secondary data were obtained from the dengue fever surveillance system. Epidemic waves were classified according to three indices: duration, intensity, and coverage. A hierarchical model of multiple logistic regression was used for the identification of risk factors, with the occurrence of extensive dengue epidemic. RESULTS: During the study period, dengue virus affected 49 of the 62 Amazonas municipalities. In 22 of these, the epidemics were of high intensity, wide range, and long time span, and therefore categorized as "extensive epidemics". The final multivariable model revealed a significant association between extensive dengue epidemics occurrence and the average number of days with precipitation (adjusted OR = 1.40, 95% CI: 1.01-1.94) and the number of years with infestation (adjusted OR = 1.53, 95% CI: 1.18-1.98). CONCLUSIONS: Our results indicate that it is crucial to integrate vector control, case management, epidemiological investigation, and health education, in order to respond to the growing threat of multiple mosquito-borne diseases, such as dengue, Zika and chikungunya, which are highly prevalent in the South America region.


Sujet(s)
Dengue/épidémiologie , Épidémies/classification , Épidémies/statistiques et données numériques , Brésil/épidémiologie , Villes , Virus de la dengue/isolement et purification , Humains , Analyse multifactorielle , Pluie , Facteurs de risque , Facteurs temps
17.
Parasit Vectors ; 10(1): 249, 2017 May 19.
Article de Anglais | MEDLINE | ID: mdl-28526066

RÉSUMÉ

BACKGROUND: Transovarial transmission of dengue virus in Aedes spp. mosquitoes is considered an important mechanism for the maintenance of the virus in nature and may be implicated in the occurrence of outbreaks and epidemics of the disease. However, there are few studies involving transovarial transmission and viral vector monitoring as a surveillance tool and control strategy. The present study evaluated transovarial transmission of dengue virus in Aedes aegypti populations as a xenomonitoring strategy in municipalities of the Amazonas state. RESULTS: Aedes sp. eggs (13.164) were collected, with 30% viability of third- and fourth-instar larvae. Transovarial transmission of DENV was detected in all municipalities. The transovarial infection rate (TOR) in the municipalities was 46% of the DENV positive samples. The minimum infection rate (MIR) was 17.7 in the state, varying from 11.4 to 24.1 per 1,000 larvae tested in the respective municipalities. Four DENV serotypes were identified, with DENV I and IV being present in all municipalities investigated. The number of reported dengue fever cases varied during this period. CONCLUSIONS: Our results suggest that transovarial transmission may be an important mechanism for the maintenance and spreading of the disease in Amazonas municipalities. Using qRT-PCR, it was possible to identify the four DENV serotypes in larval samples. The methodology used in the present study proved suitable as a DENV xenomonitoring model in immature mosquitoes, contributing to the development of systems for early detection of viral circulation and predictive models for the occurrence of outbreaks and epidemics of this disease. TRIAL REGISTRATION: CAAE34025414200005015 .


Sujet(s)
Aedes/virologie , Virus de la dengue/physiologie , Dengue/transmission , Vecteurs moustiques/virologie , Animaux , Brésil/épidémiologie , Dengue/épidémiologie , Dengue/virologie , Virus de la dengue/génétique , Virus de la dengue/immunologie , Épidémies , Femelle , Humains , Larve/virologie , Ovaire/virologie , Réaction de polymérisation en chaine en temps réel , Sérogroupe
18.
PLoS One ; 11(8): e0161884, 2016.
Article de Anglais | MEDLINE | ID: mdl-27564084

RÉSUMÉ

Dengue is a major public health problem in tropical and subtropical areas worldwide. There is a lack of information on the risk factors for death due to severe dengue fever in developing countries, including Brazil where the state of Amazonas is located. This knowledge is important for decision making and the implementation of effective measures for patient care. This study aimed to identify factors associated with death among patients with severe dengue, in Amazonas from 2001 to 2013. We conducted a retrospective cohort study based on secondary data from the epidemiological surveillance of dengue provided by the Fundação de Vigilância em Saúde do Amazonas, FVS (Health Surveillance Foundation) of the Secretaria de Saúde do Amazonas, SUSAM (Health Secretariat of the State of Amazonas). Data on dengue cases were obtained from the SINAN (Notifiable Diseases Information System) and SIM (Mortality Information System) databases. We selected cases of severe dengue with laboratory confirmation, including dengue-related deaths of residents in the state of Amazonas from January 1, 2001, to December 31, 2013. The explanatory variables analyzed were sex, age, level of education, spontaneous hemorrhagic manifestations, plasma extravasation and platelet count. Patients who died due to severe dengue had more hematuria, gastrointestinal bleeding, and thrombocytopenia than the survivors. Considering the simultaneous effects of demographic and clinical characteristics with a multiple logistic regression model, it was observed that the factors associated with death were age >55 years (odds ratio [OR] 4.98), gastrointestinal bleeding (OR 10.26), hematuria (OR 5.07), and thrombocytopenia (OR 2.55). Gastrointestinal bleeding was the clinical sign most strongly associated with death, followed by hematuria and age >55 years. The study results showed that the best predictor of death from severe dengue is based on the characteristic of age >55 years, together with the clinical signs of gastrointestinal bleeding, hematuria, and low platelet count.


Sujet(s)
Dengue sévère/épidémiologie , Dengue sévère/mortalité , Adolescent , Adulte , Brésil/épidémiologie , Épidémies de maladies , Femelle , Humains , Modèles logistiques , Mâle , Adulte d'âge moyen , Odds ratio , Études rétrospectives , Facteurs de risque , Indice de gravité de la maladie , Jeune adulte
19.
Malar J ; 14: 379, 2015 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-26419523

RÉSUMÉ

BACKGROUND: Malaria is a major public health problem worldwide. In Brazil, an average of 420,000 cases of malaria have been reported annually in the last 12 years, of which 99.7 % occurred in the Amazon region. This study aimed to analyse the distribution of malaria in the State of Amazonas and the influence of indigenous malaria in this scenario, to evaluate the correlation between incidence rates and socio-economic and environmental factors, and to evaluate the performance of health surveillance services. METHODS: This ecological study used secondary data obtained from the SIVEP-MALARIA malaria surveillance programme. The relationship between demographic, socio-economic and environmental factors, the performance of health surveillance services and the incidence of malaria in Amazonas, a multiple linear regression model was used. RESULTS: The crude rate of malaria in Amazonas was 4142.72 cases per 100,000 inhabitants between 2003 and 2012. The incidence rates for the indigenous and non-indigenous populations were 12,976.02 and 3749.82, respectively, with an indigenous population attributable fraction of only 8 %. The results of the linear regression analysis indicated a negative correlation between the two socio-economic indicators (municipal human development index (MHDI) and poverty rate) and the incidence of malaria in the period. With regard to the environmental indicators (average annual deforestation rate and percentage of areas under the influence of watercourses), the correlation with the incidence rate was positive. CONCLUSIONS: The findings underscore the importance of implementing economic and social development policies articulated with strategic actions of environmental protection and health care for the population.


Sujet(s)
Conservation des ressources naturelles/statistiques et données numériques , Paludisme , Rivières , Brésil/épidémiologie , Humains , Incidence , Modèles linéaires , Paludisme/épidémiologie , Paludisme/transmission , Facteurs socioéconomiques , Analyse spatiale
20.
Water Sci Technol ; 70(3): 569-75, 2014.
Article de Anglais | MEDLINE | ID: mdl-25098890

RÉSUMÉ

Knowledge of the hydraulic behaviour is very important in the characterization of a stabilization pond, since pond hydrodynamics plays a fundamental role in treatment efficiency. An advanced hydrodynamics characterization may be achieved by carrying out measurements with tracers, dyes and drogues or using mathematical simulation employing computational fluid dynamics (CFD). The current study involved experimental determinations and mathematical simulations of a full-scale facultative pond in Brazil. A 3D CFD model showed major flow lines, degree of dispersion, dead zones and short circuit regions in the pond. Drogue tracking, wind measurements and dye dispersion were also used in order to obtain information about the actual flow in the pond and as a means of assessing the performance of the CFD model. The drogue, designed and built as part of this research, and which included a geographical positioning system (GPS), presented very satisfactory results. The CFD modelling has proven to be very useful in the evaluation of the hydrodynamic conditions of the facultative pond. A virtual tracer test allowed an estimation of the real mean hydraulic retention time and mixing conditions in the pond. The computational model in CFD corresponded well to what was verified in the field.


Sujet(s)
Hydrodynamique , Mouvements de l'eau , Étangs
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