Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros











Intervalo de año de publicación
1.
Environ Pollut ; 243(Pt B): 1008-1014, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30248600

RESUMEN

In the 21st century, severe droughts associated with climate change will increase biomass burning (BB) in Brazil caused by the human activities. Recent droughts, especially in 2005, 2010, and 2015, caused strong socioeconomic and environmental impacts. The 2015 drought considered the most severe since 1901, surpassed the 2005 and 2010 events in respect to area and duration. Herein, based on satellite data, the 2005, 2010 and 2015 drought impacts on wildfire episodes and carbon monoxide (CO) variability during the dry and the dry-to-wet transition seasons were examined. The BB occurrences in the dry season were fewer during 2015 than during 2005 (-44%) and 2010 (-47%). Contrasting, the BB events in the dry-to-wet transition season, were higher during 2015 than during 2005 (+192%) and 2010 (+332%). The BB outbreaks were concentrated in the southern and southwestern Amazon during 2005, in the Cerrado region during 2010, and mainly in the central and northern Amazon during 2015, an area normally with few fires. The CO concentration showed positive variations (up to +30%) occurred in the southern Amazon and central Brazil during the 2005 and 2010 dry seasons, and north of 20 °S during the 2015-2016 dry-to-wet transition season. The BB outbreaks and the CO emissions showed a considerable spatiotemporal variability among the droughts of 2005, 2010, and 2016, first of them driven by local conditions in the tropical North Atlantic (TNA), characterized by warm than normal sea surface waters and the other two by the El Niño occurrences.


Asunto(s)
Monóxido de Carbono/análisis , Sequías/estadística & datos numéricos , Monitoreo del Ambiente , Incendios/estadística & datos numéricos , Biomasa , Brasil , Cambio Climático , Actividades Humanas , Estaciones del Año
2.
Ars vet ; 27(3): 161-167, 2011. tab
Artículo en Inglés, Portugués | VETINDEX | ID: biblio-1462925

RESUMEN

The occurrence of neutralizing antibodies against bovine viral diarrhea virus genotypes (BVDV-1 and BVDV-2) has been confirmed by virus neutralization test (VN) in samples of blood serum from 26 cattle herds which were not BVDV vaccinated, located in the states of Minas Gerais and São Paulo, Brazil. Ten blood samples were collected from each herd, five samples from 6 to 12-month-old calves and five samples from adult bovines. Of the total samples analyzed, 102 (39.2%) were reactive to BVDV, more specifically, 81 (31.1%) were reactive to BVDV-1 and BVDV-2, seven (2.7%) were reactive to BVDV-1 only and 14 (5.4%) were reactive to BVDV-2 only. Except for two herds, in all others at least one animal was detected reactive to BVDV, however, one of them was reactive to BVDV-2 only. In six herds, neutralizing antibodies were detected in blood serum from 6 to 12-month-old calves. Therefore, were indicative of recent BVDV infection and also suggested the likely presence of an infection source in the herd. The results showed the occurrence of neutralizing antibodies against BVDV genotypes in cattle herds located in the states analyzed, but these same results demonstrated the differences in the number of bovines reactive for BVDV-1 and BVDV-2, thus demonstrating the need to use strains from each genotype in VN tests for serological diagnosis of BVDV.


A ocorrência de anticorpos neutralizantes contra os genótipos do vírus da diarréia viral bovina (BVDV-1 e BVDV-2) foi determinada pelo teste de virusneutralização (VN) em amostras de soro sangüíneo provenientes de 26 rebanhos bovinos não vacinados contra o BVDV, localizados nos Estados de Minas Gerais e São Paulo, Brasil. Foram analisadas 10 amostras por rebanho, sendo cinco de bovinos adultos e cinco de bovinos com idade entre 6 e 12 meses. Do total de 260 amostras analisadas, 102 (39,2%) reagiram ao BVDV, das quais 81 (31,1%) foram reagentes tanto ao BVDV-1 quanto ao BVDV-2, sete (2,7%) reagiram apenas ao BVDV-1 e 14 (5,4%) reagiram apenas ao BVDV-2. Com exceção de dois rebanhos, nos demais foram detectados pelo menos um animal reagente ao BVDV, entretanto, foram detectados animais reagentes apenas ao BVDV-2 em um deles. Em seis rebanhos foram detectados anticorpos neutralizantes nos bovinos da faixa etária de 6 a 12 meses, sendo, portanto, indicativos da infecção recente pelo vírus e também sugestivos da provável presença da fonte de infecção no rebanho. Os dados obtidos mostraram a ocorrência de anticorpos neutralizantes contra os genótipos do BVDV em rebanhos bovinos localizados nos Estados analisados, mas os resultados apresentaram diferenças no número de bovinos reagentes ao BVDV-1 e ao BVDV-2, ressaltando assim a necessidade da utilização de estirpes de cada genótipo nos testes de VN para o diagnóstico sorológico do BVDV.


Asunto(s)
Animales , Bovinos , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Anticuerpos Neutralizantes , Pruebas de Neutralización/veterinaria
3.
Ars vet ; 27(3): 161-167, 2011.
Artículo en Portugués | VETINDEX | ID: vti-765187

RESUMEN

A ocorrência de anticorpos neutralizantes contra os genótipos do vírus da diarréia viral bovina (BVDV-1 e BVDV-2) foi determinada pelo teste de virusneutralização (VN) em amostras de soro sangüíneo provenientes de 26 rebanhos bovinos não vacinados contra o BVDV, localizados nos Estados de Minas Gerais e São Paulo, Brasil. Foram analisadas 10 amostras por rebanho, sendo cinco de bovinos adultos e cinco de bovinos com idade entre 6 e 12 meses. Do total de 260 amostras analisadas, 102 (39,2%) reagiram ao BVDV, das quais 81 (31,1%) foram reagentes tanto ao BVDV-1 quanto ao BVDV-2, sete (2,7%) reagiram apenas ao BVDV-1 e 14 (5,4%) reagiram apenas ao BVDV-2. Com exceção de dois rebanhos, nos demais foram detectados pelo menos um animal reagente ao BVDV, entretanto, foram detectados animais reagentes apenas ao BVDV-2 em um deles. Em seis rebanhos foram detectados anticorpos neutralizantes nos bovinos da faixa etária de 6 a 12 meses, sendo, portanto, indicativos da infecção recente pelo vírus e também sugestivos da provável presença da fonte de infecção no rebanho. Os dados obtidos mostraram a ocorrência de anticorpos neutralizantes contra os gen&o

4.
Ars vet ; 26(3): 147-152, 2010. graf
Artículo en Portugués | VETINDEX | ID: biblio-1419098

RESUMEN

O presente estudo teve como objetivo avaliar os títulos de anticorpos de bezerras de zero a doze meses de idade, em três propriedades de baixa, média e alta prevalência de BoHV-1. Os soros colhidos periodicamente foram analisados e titulados pelo teste de vírus-neutralização. Em rebanho de baixa prevalência de BoHV-1, não existiu diferença nos títulos de anticorpos colostrais entre filhas de vacas vacinadas e não vacinadas contra o BoHV-1. Em rebanhos de média e alta prevalência de BoHV-1, os títulos de anticorpos foram mais elevados nas bezerras nascidas de vacas positivas e vacinadas contra BoHV-1. A avaliação zootécnica demonstrou que quando as bezerras são manejadas corretamente e mantidas com cuidados de higiene sanitária e alimentação balanceada, não sofrem infecção em quaisquer circunstâncias de prevalência de BoHV-1. Assim, o manejo é fundamental quando se tem por objetivo controlar e/ou erradicar o BoHV-1 do rebanho.


This study aimed to evaluate the antibody titers of calves from zero to twelve months in three properties, with low, medium and high prevalence of BoHV-1. Sera were collected periodically, analyzed and titrated by virus neutralization test. In herd with low BoHV-1 prevalence, there was not difference in antibody titers from colostrum in calves born from cows vaccinated or not against BoHV-1. In herds with medium and high BoHV-1 prevalence, antibody titers were greater in calves born from cows positive and vaccinated against BoHV-1. The zootechnical evaluation showed that calves well-managed in relation to hygiene and quality of feed do not get infected in any type of BoHV-1 situation prevalence. Thus, the management is essential when it aims to control or eradicate the BoHV-1 from the herd.


Asunto(s)
Animales , Femenino , Bovinos , Vacunación/veterinaria , Herpesvirus Bovino 1/inmunología , Anticuerpos/análisis , Brasil , Pruebas de Neutralización/veterinaria
5.
Ars vet ; 26(3): 147-152, 2010.
Artículo en Portugués | VETINDEX | ID: vti-765162

RESUMEN

O herpesvírus bovino tipo 1 (BoHV-1) é um importante agente infeccioso dos bovinos responsável por expressivas perdas econômicas. Assim, o presente estudo teve como objetivo avaliar os títulos de anticorpos de bezerras nascidas e criadas, durante doze meses, em três propriedades, apresentando baixa, média e alta prevalência de BoHV-1, onde foram adotadas medidas de manejo sanitário. Os soros colhidos periodicamente foram analisados e titulados pelo teste de vírus-neutralização. Os resultados mostraram que em relação à vacinação das vacas e transferência da imunidade passiva, em rebanhos de baixa prevalência de BoHV-1, não existiram diferenças nos títulos de anticorpos colostrais entre filhas de vacas vacinadas e não vacinadas contra o BoHV-1. Entretanto, em rebanhos de média e alta prevalência de BoHV-1, os títulos de anticorpos maternos foram mais elevados nas bezerras nascidas de vacas positivas e vacinadas contra BoHV-1. Com relação à avaliação zootécnica e sanitária, foi observado que quando as bezerras são manejadas corretamente, mantidas com cuidados de higiene veterinária e alimentação balanceada, não sofrem infecção em quaisquer circunstâncias de prevalência de BoHV-1, ou seja, independentemente do rebanho apresentar baixa, média ou alta prevalência para este vírus, o manejo constitui uma ferramenta fundamental quando se tem por objetivo controlar e/ou erradicar o BoHV-

8.
Anim Reprod Sci ; 89(1-4): 105-13, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16099609

RESUMEN

Stallion semen cryopreservation, despite its impact on the horse industry, is not an established technology. During the last years, a number of modifications have been proposed to the freezing process, however, a large population of stallions still have poor semen quality and fertility after frozen-thawed. Glycerol toxicity could be a reason for the variation on stallion sperm freezability. There are limited publications concerning the use of alternative cryoprotectants for equine sperm. Glycerol is contraceptive for some species and other cryoprotectors, such as amides, have been show to be a good option for freezing semen of these species. Recent reports have shown encouraging data respecting the use of amides as cryoprotectants for stallions, with more remarkable improvements for semen from stallions that freeze poorly when glycerol is used.


Asunto(s)
Amidas , Criopreservación/veterinaria , Crioprotectores , Caballos , Preservación de Semen/veterinaria , Animales , Criopreservación/métodos , Fertilidad , Masculino , Preservación de Semen/métodos
9.
Genet. mol. res. (Online) ; Genet. mol. res. (Online);3(1): 167-180, Mar. 2004.
Artículo en Inglés | LILACS | ID: lil-417575

RESUMEN

Chromobacterium violaceum is a Gram-negative beta-proteobacterium that inhabits a variety of ecosystems in tropical and subtropical regions, including the water and banks of the Negro River in the Brazilian Amazon. This bacterium has been the subject of extensive study over the last three decades, due to its biotechnological properties, including the characteristic violacein pigment, which has antimicrobial and anti-tumoral activities. C. violaceum promotes the solubilization of gold in a mercury-free process, and has been used in the synthesis of homopolyesters suitable for the production of biodegradable polymers. The complete genome sequence of this organism has been completed by the Brazilian National Genome Project Consortium. The aim of our group was to study the DNA repair genes in this organism, due to their importance in the maintenance of genomic integrity. We identified DNA repair genes involved in different pathways in C. violaceum through a similarity search against known sequences deposited in databases. The phylogenetic analyses were done using programs of the PHILYP package. This analysis revealed various metabolic pathways, including photoreactivation, base excision repair, nucleotide excision repair, mismatch repair, recombinational repair, and the SOS system. The similarity between the C. violaceum sequences and those of Neisserie miningitidis and Ralstonia solanacearum was greater than that between the C. violaceum and Escherichia coli sequences. The peculiarities found in the C. violaceum genome were the absence of LexA, some horizontal transfer events and a large number of repair genes involved with alkyl and oxidative DNA damage


Asunto(s)
Chromobacterium/genética , Proteínas Bacterianas/genética , Reparación del ADN/genética , Homología de Secuencia , Bases de Datos Genéticas , Filogenia , Disparidad de Par Base/genética , Recombinación Genética , Respuesta SOS en Genética/genética
10.
J Appl Physiol (1985) ; 91(2): 803-10, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11457797

RESUMEN

Respiratory system, lung, and chest wall mechanical properties were subdivided into their resistive, elastic, and viscoelastic/inhomogeneous components in normal rats, to define the sites of action of sevoflurane. In addition, we aimed to determine the extent to which pretreatment with atropine modified these parameters. Twenty-four rats were divided into four groups of six animals each: in the P group, rats were sedated (diazepam) and anesthetized with pentobarbital sodium; in the S group, sevoflurane was administered; in the AP and AS groups, atropine was injected 20 min before sedation/anesthesia with pentobarbital and sevoflurane, respectively. Sevoflurane increased lung viscoelastic/inhomogeneous pressures and static elastance compared with rats belonging to the P group. In AS rats, lung static elastance increased in relation to the AP group. In conclusion, sevoflurane anesthesia acted not at the airway level but at the lung periphery, stiffening lung tissues and increasing mechanical inhomogeneities. These findings were supported by the histological demonstration of increased areas of alveolar collapse and hyperinflation. The pretreatment with atropine reduced central and peripheral airway secretion, thus lessening lung inhomogeneities.


Asunto(s)
Anestésicos por Inhalación/farmacología , Pulmón/efectos de los fármacos , Éteres Metílicos/farmacología , Mecánica Respiratoria/fisiología , Anestesia por Inhalación , Animales , Atropina/farmacología , Pulmón/citología , Masculino , Pentobarbital/farmacología , Ratas , Ratas Wistar , Valores de Referencia , Mecánica Respiratoria/efectos de los fármacos , Sevoflurano
11.
Cleft Palate Craniofac J ; 37(3): 271-3, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10830806

RESUMEN

OBJECTIVE: The objective of this study was to determine the prevalence of ectopic eruption of intranasal teeth. DESIGN: This was a retrospective study, where records of children with repaired cleft lip and palate were analyzed. SETTING: The study was conducted at a large craniofacial center, the Hospital for Rehabilitation of Craniofacial Anomalies, USP, Bauru, São Paulo, Brazil. SUBJECTS: The sample consisted of 815 records from patients with bilateral cleft lip and palate (BCLP) and 1,495 records from patients with unilateral cleft lip and palate (UCLP). The age of the subjects was 5 to 10 years old and the groups included both males and females. RESULTS: The results showed that 0.61% of the children with BCLP and 0.40% of those with UCLP had an intranasal tooth. The prevalence of an intranasal tooth for the whole group was 0.48%, and it appeared to be more common in females.


Asunto(s)
Labio Leporino/complicaciones , Fisura del Paladar/complicaciones , Erupción Ectópica de Dientes/epidemiología , Brasil/epidemiología , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Masculino , Cavidad Nasal , Prevalencia , Estudios Retrospectivos , Distribución por Sexo , Erupción Ectópica de Dientes/etiología
12.
Br J Anaesth ; 84(3): 372-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10793600

RESUMEN

It is generally accepted that halothane reduces airway and tissue resistance in lungs with preexisting airway tone. However, under conditions of resting airway tone, pulmonary resistance remains unaltered. In this study, we have determined the effects of halothane on respiratory system, pulmonary and chest wall resistive, elastic and viscoelastic mechanical properties, and related the results to findings from lung histology in intact normal rats. Sixteen adult male Wistar rats were allocated randomly to one of two groups (n = 8 in each group): control or halothane group. In the control group, animals were sedated with diazepam 5 mg i.p. and anaesthetized with pentobarbital 20 mg kg-1 i.p. In the halothane group, the anaesthetic was administered at an end-tidal concentration of I MAC throughout the study. Rats were paralysed and underwent mechanical ventilation. Halothane decreased airway resistance but increased the tissue component of resistance (caused by viscoelastic elements and lung inhomogeneity). Static and dynamic elastance also increased with halothane anaesthesia. Pulmonary resistance remained unchanged. Lung histopathology demonstrated airway dilatation and a greater degree of lung collapse and hyperinflation in the halothane group. We conclude that halothane anaesthesia acts both on airway and lung tissue. In airway tissue, dilatation occurs but the lung periphery stiffens. Consequently, these opposing effects result in no overall apparent change in mechanical properties, although changes are observed during halothane anaesthesia in normal animal and subjects.


Asunto(s)
Anestésicos por Inhalación/farmacología , Halotano/farmacología , Pulmón/efectos de los fármacos , Mecánica Respiratoria/efectos de los fármacos , Resistencia de las Vías Respiratorias/efectos de los fármacos , Animales , Pulmón/patología , Masculino , Ratas , Ratas Wistar
13.
Eur Respir J ; 14(4): 751-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10573216

RESUMEN

Acute myocardial infarction (AMI) may yield several respiratory changes. Nevertheless, no comprehensive pulmonary morphological/physiological correlation has been performed under this condition. The aims of the present investigation were: 1) to determine the respiratory parameters in an experimental model of coronary artery occlusion, 2) to relate these results to findings from lung histopathology, and 3) to evaluate the effects of propranolol used prior to AMI. Twenty-eight rats were anaesthetized and mechanically ventilated. In the control group (C), a suture line was passed around the left anterior descending coronary artery (LADCA). The infarct group (I) was similarly prepared but the LADCA was ligated and infarct resulted. In the control/propranolol (CP) and infarct/propranolol (IP) groups, propranolol was intravenously injected 5 min before surgery as performed in groups C and I, respectively. Lung static (EL,st) and dynamic (EL,dyn) elastances, airway resistance (RL,int), and viscoelastic/inhomogeneous pressure (deltaP2L) were determined before and 30, 60 and 120 min after surgery. In group I, EL,st, EL,dyn, RL,int and deltaP2L increased progressively throughout the experiment, and were higher than those found in groups C, CP and IP. All respiratory parameters but EL,st remained unaltered in group IP. Lung histopathological examination demonstrated alveolar, interstitial and intrabronchial oedema in group I. Group IP showed only interstitial oedema. Acute myocardial infarction yields lung resistive, elastic and viscoelastic changes. The last two results from alveolar and interstitial oedema, respectively. The previous use of propranolol diminishes respiratory changes.


Asunto(s)
Pulmón/fisiopatología , Infarto del Miocardio/complicaciones , Edema Pulmonar/fisiopatología , Mecánica Respiratoria , Antagonistas Adrenérgicos beta/uso terapéutico , Animales , Análisis de los Gases de la Sangre , Modelos Animales de Enfermedad , Elasticidad , Pulmón/patología , Masculino , Infarto del Miocardio/tratamiento farmacológico , Propranolol/uso terapéutico , Edema Pulmonar/etiología , Edema Pulmonar/patología , Ratas , Ratas Wistar
14.
Respir Physiol ; 115(1): 35-43, 1999 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-10344413

RESUMEN

Respiratory mechanics and thoracoabdominal morphometry were determined in four sets of animal experiments before and after surgery. In group RRA the rectus abdominus muscles were removed; in RRAH rats the muscle resection was followed by lung hyperinflation; in PPM animals the defect was repaired by suturing a polypropylene mesh (Marlex); and in PPMH lung hyperinflation was performed after abdominal wall reconstruction. Lung and chest wall elastances, and chest wall viscoelastic/inhomogeneous pressures increased in RRA, RRAH and PPM groups. Static lung elastance was progressively smaller in the following order: RRA, PPM, and PPMH. In conclusion, removal of the rectus abdominus muscles and abdominal wall reconstruction could account for higher energy losses against viscoelastic and elastic forces acting on the chest wall, and these are related to a cephalad deviation of the diaphragm. Furthermore, hyperinflation reverses lung elastic modification after abdominal wall reconstruction with PPM, without beneficial effects in the presence of abdominal wall defect.


Asunto(s)
Músculos Abdominales/cirugía , Implantación de Prótesis , Mecánica Respiratoria/fisiología , Animales , Elasticidad , Pulmón/fisiología , Rendimiento Pulmonar/fisiología , Masculino , Presión , Ventilación Pulmonar/fisiología , Ratas , Ratas Wistar , Tórax/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA