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2.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 843-849, maio-jun. 2018. ilus
Article in English | LILACS, VETINDEX | ID: biblio-911619

ABSTRACT

Feather samples were obtained from the following Psittaciformes birds: Amazona amazonica, Amazona aestiva, Aratinga jandaya, Brotogeris spp., Ara ararauna and Ara chloropterus (total of 37 individuals). These birds were housed at the Wild Animal Screening Center of Maranhão, São Luís, Brazil. Four feathers were taken from the following regions: head, back, wings, belly/breast, thighs, and tail/covert. Mites were found on 17 birds (45.94%). Astigmatid mites belonging to the genera Fainalges (Xolalgidae), Chiasmalges (Psoroptoididae) and Tanyaralichus (Pterolichidae) were identified. The highest dominance coefficient was for the mite Fainalges sp. (DC= 96.29). Chiasmalges sp. was obtained only from Ara chloropterus, and Tanyaralichus was found in A. aestiva. The genus Fainalges was obtained from all the species of Psittaciformes studied, except for A. ararauna. In evaluating mite density according to body region, statistical differences were found between the back and wing regions (P= 0.041), back and thighs (P= 0.02), wings and tail (P= 0.002), belly and tail (P= 0.031) and thighs and tail (P= 0.001). The morphological variations observed in Fainalges spp. suggested the existence of three species that probably have not been described yet. This was the first record of the genus Tanyaralichus in Brazil.(AU)


As amostras de penas foram obtidas das seguintes aves da ordem Psittaciformes: Amazona amazonica, Amazona aestiva, Aratinga jandaya, Brotogeris spp., Ara ararauna e Ara chloropterus, totalizando 37 aves, alojadas no Centro de Triagem de Animais Silvestres do Maranhão, São Luís, Brasil. Colheram-se quatro penas de cada uma das regiões: cabeça, dorso, asas, ventre/peito, coxas e cauda/crisso. Verificou-se a presença de ácaros em 17 aves (45,94%). Foram identificados ácaros Astigmata, pertencentes aos gêneros Fainalges (Xolalgidae), Chiasmalges (Psoroptoididae) e Tanyaralichus (Pterolichidae), sendo o maior coeficiente de dominância correspondente ao ácaro Fainalges sp. (CD= 96,29). Chiasmalges sp. foi obtido apenas de Ara chloropterus, e Tanyaralichus foi encontrado em A. amazônica. O gênero Fainalges foi obtido de todas as espécies de Psittaciformes estudadas, exceto em A. ararauna. Na avaliação da densidade de ácaros por região do corpo, verificou-se diferença estatística entre regiões dorsal e asas (P= 0,041), dorsal e coxas (P= 0,02), asas e caudal (P=0,002), ventral e caudal (P= 0,031) e coxas e caudal (P= 0,001). Variações morfológicas observadas em Fainalges spp., sugerem a existência de três espécies provavelmente ainda não descritas. Este é o primeiro registro do gênero Tanyaralichus no Brasil.(AU)


Subject(s)
Animals , Acari/pathogenicity , Mite Infestations , Psittaciformes/metabolism
3.
Braz. j. biol ; 76(3): 568-576, tab, graf
Article in English | LILACS | ID: lil-785053

ABSTRACT

Abstract Results obtained in studies can contribute to the advancement of science and innovative methods and techniques for developing practical activities. Reporting conditions that may restrict the implementation of research is critical to ensure the optimal development of further technical studies. The objective of this study was to assess the walking stability of R. dominica on a flat and smooth surface. The study was based on the determination of mortality, morphology and walking stability of the insect outside the grain mass, on a flat and smooth surface. Mortality of adults of this Coleoptera in conditions with and without food was similar, which explains the difficulty that this insect had for accessing the food source on the flat and smooth surface. The measurements of body length (BOL), width (BOW) and height (BOH) of R. dominica were compared with those of Tribolium castaneum (Coleoptera: Tenebrionidae), which showed good ability to walk in these conditions. This study indicated that the former presents lower BOL and BOW, and greater BOH than the second, and all these variables showed differences when analyzed simultaneously by means of the construction of multivariate morphometric indices (Width × Height, Length × Height and Height × Length × Width). These morphometric variables, together with the definition of the geometry most similar to the body shape, resulted in determination of the center of gravity (CG) and static rollover threshold (SRTgeom) for both species. Rhyzopertha dominica and T. castaneum presented CGs considered high and low, respectively, and together with the values obtained for SRTgeom, may justify that R. dominica can be considered a less stable species during movement, and presents greater risk of rollover on flat and smooth surfaces.


Resumo Resultados obtidos em pesquisas podem contribuir com o avanço da ciência e inovar métodos e técnicas para o desenvolvimento de atividades práticas. Relatar condições que podem restringir à execução de pesquisas é fundamental para garantir que seja observada a técnica ideal para o desenvolvimento de estudos posteriores. O objetivo deste trabalho foi estudar a estabilidade de caminhamento de R. dominica em superfície plana e polida. O estudo se baseou na determinação da mortalidade, morfologia e estabilidade de caminhamento do inseto fora da massa de grãos, em superfície plana e polida. A mortalidade dos adultos desse Coleoptera nas condições com e sem alimento foram semelhantes, o que justifica a dificuldade que esse inseto tem em acessar a fonte alimentar andando em superfície plana e polida. As medidas obtidas do comprimento (BOL), largura (BOW) e altura (BOH) do corpo de R. dominica foram comparadas com as de Tribolium castaneum (Coleoptera: Tenebrionidae), que pode ser considerado um bom caminhador nessas condições. Esse estudo mostrou que o primeiro é menor no BOL e BOW, e maior BOH que o segundo, e que, todas essas variáveis apresentaram diferenças quando analisadas simultaneamente por meio da construção de índices morfométricos multivariados (Largura × Altura; Comprimento × Altura e Altura × Comprimento × Largura). Essas variáveis morfométricas, juntamente com a definição da forma geométrica que mais se aproxima do formato corporal, proporcionaram a determinação do centro de gravidade (CG) e do limite lateral de tombamento (SRTgeom) para ambas as espécie. Rhyzopertha dominica e T. castaneum apresentaram CGs considerados alto e baixo, respectivamente, e juntamente com os valores obtidos para os SRTgeom, podem justificar que R. dominica pode ser considerada uma espécie menos estável durante o caminhamento, e que, apresenta maiores riscos de tombamento em superfícies plana e polida.


Subject(s)
Animals , Coleoptera/physiology , Behavior, Animal/physiology , Walking/physiology , Body Weights and Measures , Brazil
4.
Arq. bras. med. vet. zootec ; 66(5): 1413-1418, Sep-Oct/2014. tab
Article in Portuguese | LILACS | ID: lil-729759

ABSTRACT

O presente estudo teve como objetivo quantificar os níveis de citocinas pró-inflamatórias, entre as quais TNF-α, interleucina-1β (IL-1β), IL-6, e anti-inflamatórias, como IL-10, interferon-γ (INF-γ), bem como comparar o efeito do tratamento convencional com o efeito do tratamento complementado pelo extrato da planta Mikania glomerata, na intoxicação experimental por Bothropoides jararaca. Foram usados ratos Wistar,divididos em três grupos: C - controle, VB - veneno botrópico + soro antiofídico e VBM - veneno botrópico + soro antiofídico + Mikania glomerata. As citocinas foram quantificadas, no soro e no homogenato desses animais, pelo teste ELISA, em três momentos (M1 - 30 minutos, M2 - seis horas e M3 - 24 horas após a inoculação do veneno). Os resultados obtidos evidenciaram que a intoxicação por veneno botrópico estimula principalmente a produção de IL-6 no soro e TNF-α, IL-1β, IL-6 no homogenato da pata de animais experimentalmente intoxicados. O tratamento complementar, com o extrato da planta Mikania glomerata, teve influência principalmente na produção de IL-6, IL-10 e IFN-γ no soro e IL-6, IL-1β e IFN-γ no homogenato. Porém, são necessários novos estudos com o extrato de Mikania glomerata para que se possa entender a ação dessa planta sobre a intoxicação botrópica, bem como verificar qual a melhor via para administrá-lo...


This experiment aimed to quantify the pro-inflammatory cytokine levels, including TNF-α, interleukin-1β (IL-1β) and IL-6 as well as the anti-inflammatory ones such as IL-10 and INF-γ. It was also proposed to compare the effect of the conventional treatment to a treatment in which was added the Mikania glomerata plant in the experimental intoxication using Bothropoides jararaca venom. It was used Wistar rats that were randomly divided into 3 groups: C - control; VB - Bothrops venom + antivenom serum; and VBM - Bothrops venom + antivenom serum + Mikania glomerata. Cytokines were quantified in the serum and paw homogenate using ELISA test in three different moments (M1- 30 minutes, M2- 6 hours and M3- 24 hours after venom injection). The intoxication by Bothropoides jararaca venoms mainly stimulated the production of IL-6 in the serum and TNF-α, IL-1β, IL-6 in paw homogenate of animals experimentally intoxicated. Adjunctive treatment with the extract of the Mikania glomerata plant mainly influenced the production of IL-6, IL-10 and IFN-γ in the serum and IL-6, IL1β and IFN-γ in paw homogenate. Further research is necessary with the extract of Mikania glomerata in order to understand the action of this plant on the Bothropoides poisoning and also to verify the best way to manage it...


Subject(s)
Animals , Rats , Bothrops , Cytokines/analysis , Mikania/adverse effects , Mikania/poisoning , Antivenins/administration & dosage , Antivenins/analysis , Rats, Wistar , Snake Venoms/analysis
5.
Braz. j. med. biol. res ; 46(10): 855-860, 24/set. 2013. graf
Article in English | LILACS | ID: lil-688555

ABSTRACT

Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Aging/physiology , Contrast Sensitivity/physiology , Photic Stimulation/methods , Pattern Recognition, Visual/physiology , Visual Acuity/physiology
6.
Arq. bras. med. vet. zootec ; 64(1): 53-57, Feb. 2012. tab
Article in Portuguese | LILACS | ID: lil-617928

ABSTRACT

Avaliaram-se, por meio de exame clínico, hemogasométrico e eletrocardiográfico, os efeitos do salbutamol e do fenoterol, administrados por via inalatória em cães. Doze cães foram distribuídos em dois grupos: os do grupo FE receberam fenoterol na dose de 2 gotas/5kg de peso vivo, diluídas em solução de cloreto de sódio 0,9 por cento por aparelho de inalação, e os do grupo SA receberam salbutamol pelo dosador de aerossol, na dose de 100mg. Foram avaliados: frequência cardíaca (FC), frequência respiratória (FR), temperatura retal (TR), pressão arterial sistólica (PAS), hemogasometria e eletrocardiograma antes e após 30min, duas horas e seis horas do uso dos fármacos. Discreta estimulação cardíaca ocorreu nos animais do grupo SA duas horas após sua administração em relação ao momento-controle, e tremores foram predominantes nestes animais. Diminuição da PAS e aumento da FR foram observados nos dois grupos, e não houve alteração significativa da onda T, da hemogasometria e do eletrocardiograma em ambos os grupos. O fenoterol provocou menor estimulação cardíaca e menos tremores comparado ao salbutamol, foi mais seguro e houve maior facilidade, menor custo e menor gasto de tempo na administração do salbutamol por inalador dosimetrado em relação ao fenoterol por nebulização.


Through physical examination, blood gas and the electrocardiographic effects of salbutamol and fenoterol, administered by inhalation in dogs was assessed. Twelve dogs were distributed into two groups: EF group animals received a fenoterol dose of 2 drops/5kg bodyweight, diluted in sodium chloride 0.9 percent inhalation device and animals in the SA group received salbutamol through aerosol feeder at a dose of 100µg. Rectal temperature (RT), heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), blood gas and electrocardiogram before and after 30min., 2h and 6 h after drug were evaluated. Mild cardiac stimulation occurred in SA group animals 2 hours after its administration compared to the control group, and tremors were predominant in these animals. A decrease in SBP and an increase in RR were observed in both animal groups and no significant alteration of the T wave in the electrocardiogram and blood gas analysis in both groups were observed. The fenoterol caused less cardiac pacing and shivering compared to salbutamol, which was more secure. However, there was more ease, lower cost and less time spent in the administration of salbutamol administered through metered-dose inhaler compared to fenoterol nebulization.

7.
J. venom. anim. toxins incl. trop. dis ; 14(1): 82-99, 2008. ilus, graf
Article in English | LILACS | ID: lil-479341

ABSTRACT

The present work evaluated histopathological aspects in experimental envenomation of dogs with Crotalus durissus terrificus venom. Twenty-eight mixed breed adult dogs were divided into three groups of seven animals each: Group I - only venom; Group II - venom + 50ml antiophidic serum + fluid therapy; Group III - venom + 50ml antiophidic serum + fluid therapy + urine alkalization. Lyophilized venom of Crotalus durissus terrificus was reconstituted in saline solution and inoculated subcutaneously at the dose of 1mg/kg body weight. Three animals of each group were subjected to euthanasia, and their muscular tissue, brain, spleen, kidneys, heart, lungs, stomach, small and large intestines, and popliteal lymph node fragments were collected for histopathological evaluation. There was myonecrosis in the inoculated limb, renal tubular degeneration, lymphoid hyperplasia of spleen, and unspecific reactive hepatitis. These results show the antigenicity and action of the venom on the immune system.


Subject(s)
Animals , Male , Female , Dogs/anatomy & histology , Crotalid Venoms/adverse effects , Crotalid Venoms/toxicity
8.
J. venom. anim. toxins incl. trop. dis ; 14(1): 100-112, 2008. ilus, graf, tab
Article in English | LILACS | ID: lil-479342

ABSTRACT

This work evaluated the clinical and therapeutic aspects as well as serum levels of venom and antivenom IgG by enzyme-linked immunosorbent assay (ELISA) in experimental envenomation of dogs with Crotalus durissus terrificus venom. Twenty-eight mixed breed adult dogs were divided into four groups of seven animals each, Group I: only venom; Group II, venom + 50 ml of anti-bothropic-crotalic serum (50mg) + fluid therapy; Group III, venom + 50 ml of anti-bothropic-crotalic serum + fluid therapy + urine alkalination; Group IV, 50 ml of anti-bothropic-crotalic serum. The lyophilized venom of Crotalus durissus terrificus was reconstituted in saline solution and subcutaneously inoculated at the dose of 1mg/kg body weight. The dogs presented clinical signs of local pain, weakness, mandibular ptosis, mydriasis, emesis and salivation. The venom levels detected by ELISA ranged from 0 to 90ng/ml, according to the severity of the clinical signs. Serum antivenom ranged from 0 to 3ug/ml and was detected for up to 138h after treatment. ELISA results showed the effectiveness of the serum therapy for the venom neutralization.


Subject(s)
Animals , Male , Female , Antivenins , Dogs , Crotalid Venoms/adverse effects , Crotalid Venoms/toxicity , Enzyme-Linked Immunosorbent Assay
9.
Mem. Inst. Oswaldo Cruz ; 102(2): 203-208, Mar. 2007.
Article in English | LILACS | ID: lil-447559

ABSTRACT

Among the flaviviruses, dengue, with its four serotypes, has spread throughout the tropics. The most advanced vaccines developed so far include live attenuated viruses, which have been tested in humans but none has been licensed. Preclinical testing of dengue vaccine candidates is performed initially in mice and in nonhuman primates. In the latter the main criteria used to assay protection are neutralizing antibodies elicited by the vaccine candidate and the magnitude and duration of peripheral viremia upon challenge of previously immunized animals. Towards the identification of wild-type viruses that could be used in challenge experiments a total of 31 rhesus monkeys were inoculated subcutaneously of wild dengue types 1, 2, and 3 viruses. The viremia caused by the different viruses was variable but it was possible to identify dengue viruses useful as challenge strains.


Subject(s)
Humans , Animals , Male , Female , Dengue Virus/classification , Dengue Virus/pathogenicity , Viremia/virology , Chlorocebus aethiops , Disease Models, Animal , Macaca mulatta/virology , Vero Cells/virology
10.
J. venom. anim. toxins incl. trop. dis ; 13(4): 800-810, 2007. ilus, tab
Article in English | LILACS | ID: lil-471142

ABSTRACT

The present study aimed at evaluating clinical and laboratory aspects during experimental envenomation by Crotalus durissus terrificus in dogs treated with antiophidic serum. Twenty-one dogs were divided into three groups of seven animals each. Group I received 1mg/kg venom (sc); Group II received 1mg/kg venom (sc), 50mg antiophidic serum (iv), and fluid therapy including 0.9 percent NaCl solution (iv); and Group III received 1mg/kg venom (sc), 50mg antiophidic serum (iv), and fluid therapy including 0.9 percent NaCl solution containing sodium bicarbonate diluted to the dose of 4mEq/kg. The clinical signs of ataxia, sedation, flaccid paralysis, mydriasis, eyeball paralysis, mandible ptosis, sialorrhea, vomiting and diarrhea observed in the dogs were very similar to those observed in humans. The decrease in hemoglobin, hematocrit, erythrocyte, platelet and fibrinogen levels, prolongation of clotting time, prothrombin time (PT) and activated partial thromboplastin time (APTT), as well as hypocellularity in the bone marrow characterized anemia, thrombocytopenia and blood incoagulability, as well as hypofibrinogenemia and decreased bone-marrow activity. Important bleeding was not observed. Increased numbers of leukocytes and neutrophils and decreased numbers of lymphocytes and eosinophils characterized an acute inflammatory response and stress caused by generalized pain. The employed antiophidic serum was effective and all animals survived.


Subject(s)
Animals , Dogs , Antivenins/administration & dosage , Antivenins/therapeutic use , Crotalid Venoms/toxicity
11.
J. venom. anim. toxins incl. trop. dis ; 13(4): 811-820, 2007. ilus, tab
Article in English | LILACS | ID: lil-471143

ABSTRACT

The present work shows laboratory aspects, electrocardiogram and histopathology results during experimental envenomation by Crotalus durissus terrificus in dogs treated with antiophidic serum. Twenty-one dogs were divided into three groups of seven animals each. Group I received 1mg/kg venom (sc); Group II received 1mg/kg venom (sc), 50mg antiophidic serum (iv) and fluid therapy including 0.9 percent NaCl solution (iv); and Group III received 1mg/kg venom (sc), 50mg antiophidic serum (iv) and fluid therapy including 0.9 percent NaCl solution containing sodium bicarbonate diluted to the dose of 4mEq/kg. Urinalysis showed brown urine, proteinuria, occult blood and myoglobinuria. Respiratory acidosis and hypotension were also observed. At the venom inoculation site, there was discreet edema, popliteal lymph node response, musculature presenting whitish areas and necrotic myositis with myoregenerative activity. There was not evidence of electrocardiographical and biochemical alterations.


Subject(s)
Animals , Dogs , Antivenins/administration & dosage , Antivenins/therapeutic use , Electrocardiography , Poisoning/pathology , Crotalid Venoms/toxicity , Clinical Laboratory Techniques
12.
Braz. j. med. biol. res ; 39(6): 791-794, June 2006. ilus
Article in English | LILACS | ID: lil-428271

ABSTRACT

The objective of the present study was to determine contrast sensitivity curves of concentric circular patterns with radial frequencies of 0.25, 0.5, 1.0, 2.0, and 4.0 cycles per degree in young and older adult volunteers. These parameters were also compared with sensitivity contrasts for sine-wave gratings. All participants had normal acuity vision and were free of identifiable ocular illness. Contrast sensitivity was measured in 6 young adults aged 19 to 23 years and 6 older adults aged 60 to 69 years using the psychophysical forced-choice method. In this paradigm the volunteers had to decide which of two stimuli contained the above radial frequencies at low contrast levels. The other neutral stimulus was gray with homogeneous luminance. We detected a decline in contrast sensitivity for older adults at all radial frequencies compared to young adults. Also, contrast sensitivity for sine-wave gratings at all measured frequencies was better, as predicted, for all young adults. Maximum sensitivities in the radial frequency contrast sensitivity function and contrast sensitivity function occurred at 0.25 and 0.5 cycles per degree, respectively, for both young and older adults. These results suggest age-related changes in the contrast sensitivity function for concentric symmetrical stimuli.


Subject(s)
Adult , Aged , Humans , Middle Aged , Aging/physiology , Contrast Sensitivity/physiology , Pattern Recognition, Visual/physiology , Photic Stimulation/methods , Visual Acuity/physiology , Age Factors
13.
J. venom. anim. toxins incl. trop. dis ; 12(2): 285-296, 2006. tab
Article in English | LILACS | ID: lil-434721

ABSTRACT

The present work aimed to evaluate the clinical and hematological aspects during experimental envenomation by Crotalus durissus terrificus in dogs treated with different antiophidic serum doses. Sixteen dogs were divided into two groups of eight animals each. Group I received 1mg/kg venom subcutaneously and 30mg antiophidic serum intravenously; Group II received 1mg/kg venom subcutaneously and 60mg antiophidic serum intravenously. In the clinical evaluation, we observed ataxia, moderate sedation, dilated pupils, sialorrhea, flaccid paralysis of mandibular muscles, and discreet edema at the site of venom inoculation. Evaluating red and white blood cells, we observed a decrease of hemoglobins, globular volume and erythrocytes, and an increase of plasmatic proteins, leukocytes, neutrophils, monocytes and lymphocytes. Clotting time increased and there was blood incoagulability with return to normal clotting time six hours after antiophidic serum administration. Animals treated with six antiophidic serum flasks had a faster recovery than the animals that received three serum flasks


Subject(s)
Animals , Male , Female , Dogs , Crotalus cascavella/administration & dosage , Crotalus cascavella/adverse effects , Crotalus cascavella/poisoning , Dogs , Crotalid Venoms/adverse effects , Crotalid Venoms/therapeutic use
14.
Braz. j. med. biol. res ; 38(3): 419-430, mar. 2005. ilus, graf
Article in English | LILACS | ID: lil-394794

ABSTRACT

An assumption commonly made in the study of visual perception is that the lower the contrast threshold for a given stimulus, the more sensitive and selective will be the mechanism that processes it. On the basis of this consideration, we investigated contrast thresholds for two classes of stimuli: sine-wave gratings and radial frequency stimuli (i.e., j0 targets or stimuli modulated by spherical Bessel functions). Employing a suprathreshold summation method, we measured the selectivity of spatial and radial frequency filters using either sine-wave gratings or j0 target contrast profiles at either 1 or 4 cycles per degree of visual angle (cpd), as the test frequencies. Thus, in a forced-choice trial, observers chose between a background spatial (or radial) frequency alone and the given background stimulus plus the test frequency (1 or 4 cpd sine-wave grating or radial frequency). Contrary to our expectations, the results showed elevated thresholds (i.e., inhibition) for sine-wave gratings and decreased thresholds (i.e., summation) for radial frequencies when background and test frequencies were identical. This was true for both 1- and 4-cpd test frequencies. This finding suggests that sine-wave gratings and radial frequency stimuli are processed by different quasi-linear systems, one working at low luminance and contrast level (sine-wave gratings) and the other at high luminance and contrast levels (radial frequency stimuli). We think that this interpretation is consistent with distinct foveal only and foveal-parafoveal mechanisms involving striate and/or other higher visual areas (i.e., V2 and V4).


Subject(s)
Adult , Humans , Contrast Sensitivity/physiology , Photic Stimulation/methods , Visual Perception/physiology , Radio Waves , Sensory Thresholds/physiology , Time Factors
15.
Braz. j. med. biol. res ; 37(3): 375-378, Mar. 2004. ilus, graf
Article in English | LILACS | ID: lil-356622

ABSTRACT

The aim of the present study was to measure contrast sensitivity curves for angular frequencies in the range between 2 and 96 cycles/360º in older human adult volunteers and to compare these measurements with the more usual contrast sensitivity functions for sine-wave gratings. All subjects were free of identifiable ocular disease and had normal acuity. We measured the contrast thresholds for young adults (N = 6; age range, 20-26 years) and older adults (N = 6; age range, 60-67 years) using the psychophysical forced-choice method. In this paradigm the volunteers had to choose the stimulus containing a test frequency at low contrast (e.g., either a sine-wave grating or an angular frequency stimulus), or another neutral stimulus at mean luminance (without any contrast). Older adults presented a loss in contrast sensitivity at high and medium angular frequencies compared to the young adults (i.e., from 8 to 96 cycles/360º). Contrary to expectation, contrast sensitivity at low angular frequencies, i.e., 2 and 4 cycles/360º, was better for the older group than for the younger group. On the other hand, contrast sensitivity for sine-wave gratings at 3 and 4 cpd was higher for young adults as expected. These results suggest age-related changes in the contrast sensitivity function for angular frequencies.


Subject(s)
Middle Aged , Humans , Adult , Contrast Sensitivity , Photic Stimulation , Visual Perception , Age Factors , Sensory Thresholds
16.
Braz. j. med. biol. res ; 35(8): 869-872, Aug. 2002. ilus
Article in English | LILACS | ID: lil-325541

ABSTRACT

The genetic characterization of dengue virus type 3 (DEN-3) strains isolated from autochthonous cases in the State of Rio de Janeiro, Brazil, in 2001 is presented. Restriction site-specific (RSS)-PCR performed on 22 strains classified the Brazilian DEN-3 viruses as subtype C, a subtype that contains viruses from Sri Lanka, India, Africa and recent isolates from Central America. Nucleic acid sequencing (positions 278 to 2550) of one DEN-3 strain confirmed the origin of these strains, since genotype III - classified by sequencing - and RSS-PCR subtype C are correlated. This genetic subtype has been associated with hemorrhagic dengue epidemics and the information provided here could be useful to implement appropriate prevention and control measures


Subject(s)
Humans , Databases, Nucleic Acid , Dengue Virus , Genome, Viral , Phylogeny , Brazil , Dengue Virus , Polymerase Chain Reaction , Restriction Mapping
17.
Southeast Asian J Trop Med Public Health ; 2002 Mar; 33(1): 68-71
Article in English | IMSEAR | ID: sea-34035

ABSTRACT

Dengue infection that is accompanied by unusual complications has been described in Brazil. We report on the presence of dengue virus in the central nervous system (CNS) of a patient who died in 1998 in Rio Grande do Norte, northeast Brazil. DEN-2 viruses were isolated from the brain liver, and lymphnode tissue of a 67-year-old man whose signs and symptoms were those of dengue infection and a secondary immune response. A postmortem revealed nose bleeds a liver that was brownish with yellow areas, and pulmonary and cerebrae congestion. Immunoperoxidase staining showed a dengue antigen-specific positive reaction in the gray matter cells of the cerebrall cortex; a granular citoplasmatic reaction was seen in the neurons. Dengue infection should always be considered as a cause encephalitis in tropical countries, especially in those where the disease is endemic.


Subject(s)
Aged , Brazil , Central Nervous System Infections/diagnosis , Dengue/diagnosis , Fatal Outcome , Humans , Male
18.
Rev. Soc. Bras. Med. Trop ; 34(1): 49-52, jan.-fev. 2001. tab
Article in Portuguese | LILACS | ID: lil-462073

ABSTRACT

The immune humoral response induced by the rabies vaccine produced in suckling mouse brain was studied in 23 dogs. The mouse neutralization test (MNT) was used to evaluate the level of rabies antibodies. Ten dogs received vaccine stored at 2 to 8 degrees C, showing the following results: 30 days after vaccination, six samples (60%) responded to the MNT; 180 days after vaccination, 4 samples (40%); and 360 days after vaccination, only one sample (10%). The remaining 13 dogs received previously frozen vaccine and 30 days after vaccination, only two samples (l5.4%) responded to the MNT. No titers were detected 180 and 360 days after vaccination. Statistical analysis of each variable used Tuckey analysis of variance, which showed statistically significant differences between the two groups.


A resposta imune humoral induzida pela vacina contra a raiva produzida em cérebros de camundongos recém-nascidos foi estudada em 23 cães e o teste de soroneutralização em camundongos foi usado para avaliação dos níveis de anticorpos rábicos. Um grupo com 10 animais recebeu vacina conservada de 2 a 8oC e apresentou os seguintes resultados: após 30 dias da vacinação 6 (60%) amostras responderam ao teste; após 180 dias 4 (40%) e após 360 dias apenas 1 (10%). O outro grupo com 13 cães recebeu vacina previamente congelada e somente 2 (15,4%) amostras no dia 30 apresentaram resposta satisfatória; os demais períodos (180 e 360) após a vacinação, não foi encontrado título. A análise estatística dos dados referentes a cada uma das variáveis consideradas no estudo foi efetuada segundo a técnica de análise de variância seguida por Tuckey e indicaram diferenças estatisticamente significativas entre os grupos.


Subject(s)
Animals , Dogs , Mice , Antibodies, Viral/biosynthesis , Freezing , Rabies Vaccines , Rabies/immunology , Rabies/prevention & control , Brain
19.
Mem. Inst. Oswaldo Cruz ; 93(2): 155-9, Mar.-Apr. 1998. tab, graf
Article in English | LILACS | ID: lil-203588

ABSTRACT

A retrospective serologic study was carried out in Fortaleza, State of Ceará, Brazil, in order to detect the dengue virus activity before recognizing the epidemic of 1994. Mac-Elisa was performed by using a mixture of specific DEN-1 and DEN-2 antigens on serum samples from the Emilio Ribas Laboratory collection. Samples were obtained from 1,224 patients with exanthematic febrile disease and negative serological results for rubella. All specimens were taken during November 1993 to May 1994. The results confirmed dengue infections in Fortaleza by November 1993, approximately six months before the beginning of the epidemic, proving how misleading diagnosis of dengue infection are still troublesome, in spite of the strong dengue activity in Ceará. The authors stress the urgent necessity to implement the active surveillance system in order to prevent another extensive fever epidemics in the state. Epidemiological background of the dengue activity in the State of Ceará is also described.


Subject(s)
Humans , Dengue , Brazil , Retrospective Studies
20.
Rev. Soc. Bras. Med. Trop ; 30(5): 379-383, set.-out. 1997. tab, graf
Article in English | LILACS | ID: lil-464358

ABSTRACT

Um inquérito soroepidemiológico foi realizado em uma amostra de escolares, em 1994, no município de Paracambi, Estado do Rio de Janeiro. Positividade do teste de Inibição da Hemaglutinação foi detectada em 39,2% (145/370) dos escolares pesquisados. A freqüência de positividade foi de 53,8% (78/145) para o sexo feminino e de 46,2% (67/145) para o sexo masculino. A distribuição por faixa etária mostrou uma positividade crescente com o aumento da idade. Cepas do vírus dengue tipo 1 e vírus dengue tipo 2 foram isoladas anteriormente (1990), mostrando a co-circulação de ambos os sorotipos na área. Os índices de infestação predial pelo Aedes aegypti e pelo Aedes albopictus foram determinados.


A seroepidemiological survey was carried out during 1994 in the municipality of Paracambi, state of Rio de Janeiro. Haemagglutination inhibition test positivity was detected in 145 out of 370 (39.2%) schoolchildren. The frequency of positive test by sex was 53.8% (78/145) female and 46.2% (67/145) male. Distribution by age showed the increasing of antibody positivity in older children. Strains of dengue virus type 1 and dengue virus type 2 were isolated before (1990) showing the co-circulation of both serotypes in that area. The house index infestation of Aedes albopictus and Aedes aegypti has been determined.


Subject(s)
Adolescent , Animals , Child , Child, Preschool , Female , Humans , Male , Dengue/epidemiology , Aedes , Age Distribution , Antibodies, Viral/blood , Brazil/epidemiology , Dengue/immunology , Dengue/transmission , Insect Vectors , Prevalence , Seroepidemiologic Studies , Sex Distribution , Dengue Virus/immunology
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