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1.
Toxicol Appl Pharmacol ; 468: 116525, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37076090

RESUMO

Smoking can lead to several diseases and cause a reduction in fertility in men and women. Among the various components of cigarettes harmful during pregnancy, nicotine stands out. It can cause a reduction in placental blood flow, compromising the development of the baby with neurological, reproductive and endocrine consequences. Thus, we aimed to evaluate the effects of nicotine on the pituitary-gonadal axis of rats exposed during pregnancy and breastfeeding (1st generation - F1), and whether the possible damage observed would reach the 2nd generation (F2). Pregnant Wistar rats received 2 mg/kg/day of nicotine throughout the entire gestation and lactation. Part of the offspring was evaluated on the first neonatal day (F1) for macroscopic, histopathological and immunohistochemical analyses of brain and gonads. Another part of the offspring was kept until 90 days-old for mating and obtainment of progenies that had the same parameters evaluated at the end of pregnancy (F2). The occurrence of malformations was more frequent and diversified in nicotine-exposed F2. Brain alterations, including reduced size and changes in cell proliferation and death, were seen in both generations of nicotine-exposed rats. Male and female gonads of F1 exposed rats were also affected. The F2 rats showed reduced cellular proliferation and increased cell death on the pituitary and ovaries, besides increased anogenital distance in females. The number of mast cells was not enough altered to indicate an inflammatory process in brain and gonads. We conclude that prenatal exposure to nicotine causes transgenerational alterations in the structures of pituitary-gonadal axis in rats.


Assuntos
Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Ratos , Gravidez , Feminino , Animais , Masculino , Humanos , Exposição Materna/efeitos adversos , Nicotina/toxicidade , Ratos Wistar , Placenta , Reprodução
2.
Toxicol Appl Pharmacol ; 426: 115638, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34242569

RESUMO

Gonadal development begins in the intrauterine phase and females from most species are born with an established oocyte reserve. Exposure to drugs during gestation can compromise the offspring health, also affecting the gametes quality. Nicotine, the main component of cigarettes, is an oxidant agent capable of altering the fertility in men and women. As female gametes are susceptible to oxidative stress, this drug can damage the oolemma and affect oocyte maturation, induce errors during chromosomal segregation and DNA fragmentation. Oocyte mitochondria are particularly susceptible to injuries, contributing to the oocyte quality loss and embryonic development disruption. Thus, considering the high number of women who smoke during pregnancy, while significant events are occurring in the embryo for future fertility of offspring, we seek to verify the quality of the oocytes from adult rats exposed to nicotine during intrauterine phase and breastfeeding. Pregnant Wistar rats received nicotine by osmotic mini-pumps and the female progenies were evaluated in adulthood for oocyte quality (viability, lipid peroxidation, generation of reactive oxygen species and mitochondrial integrity) and reproductive capacity. Embryos (3dpc) and fetuses (20dpc) generated by these rats were also evaluated. The results showed that the dose of 2 mg/kg/day of nicotine through placenta and breast milk does not affect the number of oocytes and the fertility capacity of adult rats. However, it causes some morphological alterations in oocytes, mitochondrial changes, embryonic fragmentation and disruption of fetal development. The malformations in fetuses generated from these gametes can also indicate the occurrence of epigenetic modifications.


Assuntos
Nicotina/toxicidade , Oócitos/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Reprodução/efeitos dos fármacos , Animais , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Lactação , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Troca Materno-Fetal , Mitocôndrias/efeitos dos fármacos , Oócitos/metabolismo , Gravidez , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-31111183

RESUMO

Albinism is a rare phenotype that affects the pigmentation in eyes, hair, and skin. The effects of albinism in color vision are still unclear. Our study aimed to evaluate the color vision phenotype and genotype of an albino capuchin monkey. An adult albino male capuchin monkey (Sapajus apella) had the L and M opsin gene analyzed, and was trained in a behavioral task of color discrimination. Color discrimination thresholds were determined along 20 chromatic axes around the background chromaticity. A color discrimination ellipse was drawn by interpolation among these thresholds. The albino monkey's behavioral color discrimination ellipse showed poor discrimination along the red-green axis indicating a deutan phenotype. Genetic analysis revealed only the presence of the L gene in the albino monkey. This result did not differ from that obtained with ten previously tested non-albino monkeys. Behavioral and molecular analyses agreed that the albino capuchin monkey had color vision similar to that of non-albino dichromat monkeys, suggesting no influence of albinism on color discrimination.


Assuntos
Albinismo Oculocutâneo/veterinária , Visão de Cores/fisiologia , Sapajus apella/genética , Animais , Genótipo , Masculino , Opsinas/genética , Fenótipo
4.
Braz J Med Biol Res ; 52(2): e7559, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30698224

RESUMO

The visual system of women changes during pregnancy. Few reports have addressed the effects of pregnancy on color vision. We aimed to compare the color vision of women in the first, second, and third trimesters of pregnancy. Fifty women were divided into first (n=10), second (n=10), third trimester pregnancy groups (n=10), and non-pregnant group (n=20). We used the Farnsworth D15 and Lanthony desaturated D15 (D15d) tests. The hue ordering quantified the amount of error (C-index) and the chromatic selectivity of the errors (S-index). Bland-Altman analysis was applied to the hue ordering data. No difference was found for Farnsworth D15 test results obtained from the pregnant groups and the non-pregnant group (P<0.0083). For the Lanthony D15 desaturated test, the third trimester pregnant group had higher C-index and S-index than non-pregnant women and first-trimester pregnant women (P<0.0083). The Bland-Altman analysis showed that the limits of agreement increased as pregnancy advanced, and the errors were biased to the D15d test. In this study, color vision was impaired during pregnancy. Color vision evaluation could be used as an indicator of the functional status of the central vision during pregnancy.


Assuntos
Percepção de Cores , Visão de Cores , Testes Visuais/métodos , Adulto , Feminino , Humanos , Gravidez , Complicações na Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez
5.
Braz. j. med. biol. res ; 52(2): e7559, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-984027

RESUMO

The visual system of women changes during pregnancy. Few reports have addressed the effects of pregnancy on color vision. We aimed to compare the color vision of women in the first, second, and third trimesters of pregnancy. Fifty women were divided into first (n=10), second (n=10), third trimester pregnancy groups (n=10), and non-pregnant group (n=20). We used the Farnsworth D15 and Lanthony desaturated D15 (D15d) tests. The hue ordering quantified the amount of error (C-index) and the chromatic selectivity of the errors (S-index). Bland-Altman analysis was applied to the hue ordering data. No difference was found for Farnsworth D15 test results obtained from the pregnant groups and the non-pregnant group (P<0.0083). For the Lanthony D15 desaturated test, the third trimester pregnant group had higher C-index and S-index than non-pregnant women and first-trimester pregnant women (P<0.0083). The Bland-Altman analysis showed that the limits of agreement increased as pregnancy advanced, and the errors were biased to the D15d test. In this study, color vision was impaired during pregnancy. Color vision evaluation could be used as an indicator of the functional status of the central vision during pregnancy.


Assuntos
Humanos , Feminino , Gravidez , Adulto , Testes Visuais/métodos , Percepção de Cores , Visão de Cores , Complicações na Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Primeiro Trimestre da Gravidez
6.
Braz J Med Biol Res ; 46(2): 154-63, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23369980

RESUMO

The purpose of the present study was to measure contrast sensitivity to equiluminant gratings using steady-state visual evoked cortical potential (ssVECP) and psychophysics. Six healthy volunteers were evaluated with ssVECPs and psychophysics. The visual stimuli were red-green or blue-yellow horizontal sinusoidal gratings, 5° × 5°, 34.3 cd/m2 mean luminance, presented at 6 Hz. Eight spatial frequencies from 0.2 to 8 cpd were used, each presented at 8 contrast levels. Contrast threshold was obtained by extrapolating second harmonic amplitude values to zero. Psychophysical contrast thresholds were measured using stimuli at 6 Hz and static presentation. Contrast sensitivity was calculated as the inverse function of the pooled cone contrast threshold. ssVECP and both psychophysical contrast sensitivity functions (CSFs) were low-pass functions for red-green gratings. For electrophysiology, the highest contrast sensitivity values were found at 0.4 cpd (1.95 ± 0.15). ssVECP CSF was similar to dynamic psychophysical CSF, while static CSF had higher values ranging from 0.4 to 6 cpd (P < 0.05, ANOVA). Blue-yellow chromatic functions showed no specific tuning shape; however, at high spatial frequencies the evoked potentials showed higher contrast sensitivity than the psychophysical methods (P < 0.05, ANOVA). Evoked potentials can be used reliably to evaluate chromatic red-green CSFs in agreement with psychophysical thresholds, mainly if the same temporal properties are applied to the stimulus. For blue-yellow CSF, correlation between electrophysiology and psychophysics was poor at high spatial frequency, possibly due to a greater effect of chromatic aberration on this kind of stimulus.


Assuntos
Sensibilidades de Contraste/fisiologia , Potenciais Evocados Visuais/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Percepção de Cores/fisiologia , Eletrofisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa , Psicofísica
7.
Braz. j. med. biol. res ; 46(2): 154-163, 01/fev. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-668780

RESUMO

The purpose of the present study was to measure contrast sensitivity to equiluminant gratings using steady-state visual evoked cortical potential (ssVECP) and psychophysics. Six healthy volunteers were evaluated with ssVECPs and psychophysics. The visual stimuli were red-green or blue-yellow horizontal sinusoidal gratings, 5° × 5°, 34.3 cd/m2 mean luminance, presented at 6 Hz. Eight spatial frequencies from 0.2 to 8 cpd were used, each presented at 8 contrast levels. Contrast threshold was obtained by extrapolating second harmonic amplitude values to zero. Psychophysical contrast thresholds were measured using stimuli at 6 Hz and static presentation. Contrast sensitivity was calculated as the inverse function of the pooled cone contrast threshold. ssVECP and both psychophysical contrast sensitivity functions (CSFs) were low-pass functions for red-green gratings. For electrophysiology, the highest contrast sensitivity values were found at 0.4 cpd (1.95 ± 0.15). ssVECP CSF was similar to dynamic psychophysical CSF, while static CSF had higher values ranging from 0.4 to 6 cpd (P < 0.05, ANOVA). Blue-yellow chromatic functions showed no specific tuning shape; however, at high spatial frequencies the evoked potentials showed higher contrast sensitivity than the psychophysical methods (P < 0.05, ANOVA). Evoked potentials can be used reliably to evaluate chromatic red-green CSFs in agreement with psychophysical thresholds, mainly if the same temporal properties are applied to the stimulus. For blue-yellow CSF, correlation between electrophysiology and psychophysics was poor at high spatial frequency, possibly due to a greater effect of chromatic aberration on this kind of stimulus.


Assuntos
Adulto , Feminino , Humanos , Masculino , Sensibilidades de Contraste/fisiologia , Potenciais Evocados Visuais/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção de Cores/fisiologia , Eletrofisiologia , Estimulação Luminosa , Psicofísica
8.
Arq. Inst. Biol ; 80(1): 83-89, jan.-mar.2013. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1462208

RESUMO

O objetivo do presente trabalho foi avaliar a eficácia de glyphosate e 2,4-D, isolados e em mistura, no controle de Commelina villosa. Foram estudadas duas metodologias de avaliação de absorção de herbicidas em oito intervalos de tempo para a lavagem (simulando chuva após a aplicação) e corte (simulando abortamento, como estratégia de defesa) das folhas: 2, 4, 6, 8, 12, 24 e 48 horas após a aplicação dos herbicidas, além de um tratamento sem lavagem ou corte das folhas, em delineamento experimental inteiramente casualizado com quatro repetições, dispostos em um esquema fatorial 3 x 7 + 1 (três herbicidas x sete períodos – horas após a aplicação). Os herbicidas e doses testados foram: glyphosate (1.440 g ha-1), 2,4-D (720 g ha-1) e a mistura glyphosate + 2,4-D (1.080 + 720 g ha-1). A simulação de chuva interferiu de forma negativa no controle das plantas com o herbicida glyphosate. O controle com o herbicida 2,4-D foi influenciado apenas no período de 2 horas. Os períodos de simulação de chuva não influenciaram no controle das plantas com a mistura de glyphosate + 2,4-D. Para o estudo com corte das folhas tratadas, todos os tratamentos independente do período para corte das folhas foram influenciados de forma negativa no controle, sendo que as plantas apresentaram rebrotas quando tratadas com o herbicida 2,4-D isolado.


Efficacy of glyphosate and 2,4-d in the control of Commelina Villosa. The aim of this study was to evaluate the efficacy of glyphosate and 2,4-D alone and in combination, in the control of Commelina villosa. We studied two methodologies for evaluating herbicide absorption in eight time intervals for washing (simulating rainfall after application) and cutting of leaves (simulating abortion as a defense strategy): 2, 4, 6, 8, 12, 24 and 48 hours after herbicide application, and a treatment without washing or cutting the leaves in a completely randomized design with four replications in a 3 x 7 + 1 factorial design (three herbicides x seven periods – hours after application). Herbicides and doses tested were: glyphosate (1,440 g ha-1), 2,4-D (720 g ha-1) and a mixture of glyphosate + 2,4-D (1,080 + 720 g ha-1). The simulation of rain interfered negatively in the plant control with glyphosate. The control with the herbicide 2,4-D was affected only for the period of 2 hours. Periods of rain simulation did not influence the control of plants with a mixture of glyphosate + 2,4-D. For the study with the cutting of treated leaves, all treatments regardless of the period of cutting the leaves were influenced negatively in terms of plant control, the plants showing regrowth when treated with 2,4-D alone.


Assuntos
Commelina/classificação , Herbicidas/análise , Plantas Daninhas/parasitologia
9.
Arq. Inst. Biol ; 80(2): 177-182, 20130000.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1462230

RESUMO

Eichhornia crassipes is one of the main weeds found in aquatic environments, being undesirable for many activities. The aim of this study was to evaluate the translocation of glyphosate and imazamox in E. crassipes. Eight intervals were studied for cutting leaves that received herbicides: 2, 4, 6, 8, 12 and 24 hours after application (HAA), and a treatment with no cutting (untreated). The glyphosate dose was 2,160 g a.e. ha-1 (commercial product - Rodeo) + 0.5% v v-1 Aterbane adhesive spreader and imazamox at 290.4 g i.a. ha-1 (commercial product - Clearcast). The treatments were installed in a completely randomized design with four replications. Glyphosate showed a bad control for all the periods of leaf cutting. The imazamox did not provide control within 12 HAA, while from 24 HAA onward the control was effective. There was not a great mobility of the glyphosate molecule in water hyacinth plants, a period above 24 hours being needed for a satisfactory translocation. For imazamox at least 24 hours were needed after herbicide application for the translocation to occur along with subsequent control.


Entre as diversas plantas daninhas encontradas em ambientes aquáticos, a Eichhornia crassipes é uma das principais, sendo espécie indesejável para muitas atividades. O objetivo deste trabalho foi avaliar a translocação de glyphosate e imazamox em plantas de E. crassipes. Foram estudados oito intervalos de tempo para o corte das folhas que receberam os herbicidas: 2, 4, 6, 8, 12 e 24 horas após a aplicação (HAA) dos produtos, além de um tratamento sem corte das plantas (testemunha). Utilizaram-se glyphosate na dose de 2.160 g e.a. ha-1 (produto comercial - Rodeo) + 0,5% v v-1 do espalhante adesivo aterbane e imazamox na dose de 290,4 g i.a. ha-1 (produto comercial - Clearcast). Os tratamentos foram instalados em um delineamento experimental inteiramente casualizado com quatro repetições. O glyphosate apresentou um controle insatisfatório quando realizado os cortes das folhas em todos os períodos avaliados. O herbicida imazamox não proporcionou controle em até 12 HAA, enquanto que a partir de 24 HAA do herbicida o controle foi eficiente. Não houve uma grande mobilidade da molécula de glyphosate nas plantas de aguapé, sendo necessário um período superior a 24 horas para uma translocação satisfatória. Já para o imazamox um tempo de mínimo de 24 horas após a aplicação do herbicida foi suficiente para que ocorresse a translocação e um posterior controle.


Assuntos
Eichhornia , Flora Aquática , Herbicidas
10.
Transplant Proc ; 44(8): 2384-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23026600

RESUMO

BACKGROUND: Gastrointestinal (GI) complications are common after renal transplantation, mainly owing to immunosuppressive therapy. Assessment of GI transit time can facilitate rational management of these disorders. OBJECTIVE: We evaluate the GI transit parameters in renal transplant recipients taking tacrolimus, azathioprine, and prednisone with the use of the alternate current biosusceptometry (ACB) technique and compared them with healthy volunteers. METHODS: Ten renal transplant recipients and 10 healthy volunteers were enrolled in this study. After an overnight fast, patients and volunteers ingested a standard meal containing magnetic markers. The biomagnetic monitoring was performed at 10-minute intervals for at least 8 hours to obtain gastric emptying as well as the colonic arrival time-intensity curves. Mean gastric emptying time (MGET), mean colon arrival time (MCAT), and mean small intestinal transit time (MSITT) were quantified and compared between control and patient groups with results expressed as mean ± SD. RESULTS: The MGET measured by the ACB technique was 48 ± 31 minutes and 197 ± 50 minutes for patients and healthy subjects, respectively. MSITT and MCAT values calculated for patients versus volunteers were 171 ± 71 minutes versus 197 ± 71 minutes and 219 ± 83 minutes versus 373 ± 52 minutes, respectively. Renal transplant recipients showed significantly faster; gastric emptying and colon arrival times (P < .001) compared with normal volunteers; however, small intestinal transit time was not significantly different (P = .44). CONCLUSIONS: In stable renal transplant recipients, the GI transit parameters were significantly faster than in normal healthy volunteers. ACB sensors are versatile technologies that can be used for clinical research, because they offer an excellent opportunity to evaluate GI transit in a noninvasive manner without the use of ionizing radiation.


Assuntos
Técnicas de Diagnóstico do Sistema Digestório , Esvaziamento Gástrico , Gastroenteropatias/diagnóstico , Transplante de Rim/efeitos adversos , Magnetismo , Adulto , Estudos de Casos e Controles , Técnicas de Diagnóstico do Sistema Digestório/instrumentação , Feminino , Gastroenteropatias/etiologia , Gastroenteropatias/fisiopatologia , Trânsito Gastrointestinal , Humanos , Imunossupressores/efeitos adversos , Magnetismo/instrumentação , Imãs , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
11.
Braz. j. med. biol. res ; 45(10): 955-961, Oct. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-647757

RESUMO

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.


Assuntos
Adulto , Humanos , Potenciais Evocados Visuais/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Reprodutibilidade dos Testes , Percepção Espacial/fisiologia , Percepção do Tempo , Córtex Visual/fisiologia , Campos Visuais/fisiologia
12.
Braz J Med Biol Res ; 45(10): 955-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22782556

RESUMO

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.


Assuntos
Potenciais Evocados Visuais/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Adulto , Humanos , Reprodutibilidade dos Testes , Percepção Espacial/fisiologia , Percepção do Tempo , Córtex Visual/fisiologia , Campos Visuais/fisiologia
13.
Bull Environ Contam Toxicol ; 89(1): 119-24, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22527003

RESUMO

Our objective was to evaluate the temporal evolution of mercury exposure in two riverside communities, Barreiras and São Luiz do Tapajós, downstream of gold mining areas in the Tapajós basin, Brazilian Amazon. The quantification of mercury in hair sample was made by atomic absorption spectrophotometry in the period between 1994 and 2010. In São Luiz do Tapajós the mercury exposure varied, in log units, from the peak of 1.21 ± 0.03 µg/g in 1996 to 1.16 ± 0.07 µg/g in 2007. Mercury exposure in Barreiras varied, in log units, from 1.25 ± 0.04 µg/g in 1994 to 1 ± 0.03 µg/g in 2010, peaking in 1995 at 1.25 ± 0.06 µg/g. Total mercury concentration found in both communities had no statistical differences across the years (p > 0.05) and they were higher than non-mercury exposed communities in Brazil and in South America. We concluded that the mercury exposure in the Tapajós basin is more than regulatory levels or higher than the general population.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Cabelo/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Adulto , Brasil , Feminino , Contaminação de Alimentos/estatística & dados numéricos , Cabelo/química , Humanos , Masculino , Mercúrio/análise , Pessoa de Meia-Idade , Mineração , Características de Residência , Rios/química , Poluentes Químicos da Água/análise
14.
Appl. radiat. isot ; 69(12): 1748-1751, Dec. 2011.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1059758

RESUMO

Antiproliferative and oxidative damage effects occurring in Boron Neutron Capture Therapy (BNCT) in normal fibroblasts and melanoma cell lines were analyzed. Melanoma cells and normal fibroblasts were treated with different concentrations of Boronophe- nylalanine and irradiated with thermal neutron flux. The cellular viability and the oxidative stress were determined. BNCT induced free radicals production and proliferative potential inhibition in melanoma cells. Therefore, this therapeutic technique could be considered efficient to inhibit growth of melanoma with minimal effects on normal tissues.


Assuntos
Células Cultivadas/efeitos da radiação , Melanoma/radioterapia , Radicais Livres/efeitos da radiação , Radicais Livres/provisão & distribuição
15.
Appl Radiat Isot ; 69(12): 1748-51, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21620718

RESUMO

Antiproliferative and oxidative damage effects occurring in Boron Neutron Capture Therapy (BNCT) in normal fibroblasts and melanoma cell lines were analyzed. Melanoma cells and normal fibroblasts were treated with different concentrations of Boronophenylalanine and irradiated with thermal neutron flux. The cellular viability and the oxidative stress were determined. BNCT induced free radicals production and proliferative potential inhibition in melanoma cells. Therefore, this therapeutic technique could be considered efficient to inhibit growth of melanoma with minimal effects on normal tissues.


Assuntos
Terapia por Captura de Nêutron de Boro , Radicais Livres/metabolismo , Melanoma Experimental/radioterapia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos
16.
Bull Environ Contam Toxicol ; 86(5): 506-10, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21461739

RESUMO

The objective of this study was to identify pesticides found in infants' and children's diets. Fruits and vegetables were collected from 2004 to 2007 and analyzed using a multiresidue method. The most frequently detected residues were procymidone, captan, chlorpyrifos and chlorothalonil. Twenty-eight percent of the samples contained pesticide residues. Strawberry, pear, apple, peach and tomato contained pesticide levels of concern. Twenty-one pesticides were found with the estimated total mean daily intake greater than the acceptable daily intake for four of the pesticides. Residues of carbaryl, diazinon and methidathion exceeded regulatory levels in (apple, strawberry, and orange).


Assuntos
Dieta/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Análise de Alimentos , Resíduos de Praguicidas/análise , Criança , Humanos , Lactente
17.
Doc Ophthalmol ; 122(2): 77-86, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21290166

RESUMO

The effects of chloroquine intake on the retinal function in a Brazilian population of patients were assessed by multifocal electroretinography. Twenty-four randomly chosen eyes of patients treated with chloroquine for rheumatoid arthritis and systemic lupus erythematosus were examined using multifocal electroretinography (mfERG). Control measurements were acquired from 21 randomly chosen eyes of age-matched healthy subjects. None of the study participants had an inherited retinal disease or a Snellen visual acuity reduced to less than 20/40. In patients and control subjects, cumulative chloroquine dose, total daily dose, duration of treatment, retinal examination, visual field defects, visual acuity, and the mfERG were assessed. The average amplitudes and implicit times of the N1, P1, and P2 components of the mfERGs were measured in the central hexagon (R1) and in five rings (R2-R6). The values measured in patients and normal subjects were compared. The P1 amplitudes in R2 were significantly decreased in the patients. In addition, the amplitudes of N1 and N2 in R1 were significantly smaller in the patients. The implicit times of none of the components were significantly different between patients and controls. The response amplitude was not significantly correlated with cumulative dose and duration of intake. There was no correlation with retinal appearance, visual field, and visual acuity. In agreement with earlier data, the central mfERG amplitudes were decreased in chloroquine patients indicating functional alterations in the retina. These changes are also present in a Brazilian population suggesting that the effects of chloroquine are general and that genetic background and life circumstances probably have, if at all, only little effect.


Assuntos
Antirreumáticos/efeitos adversos , Cloroquina/efeitos adversos , Eletrorretinografia/efeitos dos fármacos , Retina/fisiopatologia , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/fisiopatologia , Adulto , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Brasil , Cloroquina/uso terapêutico , Feminino , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Retina/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos , Campos Visuais/efeitos dos fármacos , Adulto Jovem
18.
Ophthalmic Physiol Opt ; 30(5): 518-24, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20883335

RESUMO

Transient visual evoked cortical potentials (VECP) were recorded from the scalp of healthy normal trichromats (n = 12). VECPs were elicited by onset/offset presentation of patterned stimuli of two kinds: isochromatic luminance-modulated, and equiluminant red-green modulated, sine wave gratings. The amplitude and latency of the major onset components of the onset/offset VECP were measured and plotted as a function of the logarithm of pooled cone contrast. The early onset components, achromatic C1 and chromatic N1, increase linearly with log contrast, but N1 has a higher contrast gain than C1. The late onset components, achromatic C2 and chromatic N2, have similar contrast gain, and similar response as a function of contrast level: both increase in the low-to-medium range of contrasts and saturate at high contrast levels. In the range of pooled cone contrast tested, C1 and N1 show similar latencies, whilst C2 shows shorter latencies than N2. We suggest that C1 and N1 are generated by the same visual mechanism with high red-green contrast gain and low luminance contrast gain, whilst C2 and N2 are generated by different visual mechanisms.


Assuntos
Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Potenciais Evocados Visuais/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Psicofísica , Tempo de Reação/fisiologia , Adulto Jovem
19.
Cad Saude Publica ; 16(3): 701-8, 2000.
Artigo em Português | MEDLINE | ID: mdl-11035509

RESUMO

A survey was conducted to identify socioeconomic conditions and attitudes towards household prevention of American cutaneous leishmaniasis in Corte de Pedra, located in the county of Tancredo Neves, an endemic region in southern Bahia, Brazil. A questionnaire was applied in July 1997, focusing on social and economic variables, habits, and attitudes towards prevention of arthropod bites. All families (100%) living in the study area were surveyed, comprising 168 households with 851 individuals. Approximately 66.7% of the families earned up to one minimum wage, supporting an average of 5.1 residents per household. Most (57.2%) of the families did not use any type of protection against bites. Fumigation by burning various types of materials was the most customary form of prevention. Individual protection measures were rarely used. Since there was evidence of household and peridomiciliary transmission in the study area, use of impregnated bed nets is an alternative for intradomiciliary protection.


Assuntos
Atitude Frente a Saúde , Doenças Endêmicas/prevenção & controle , Habitação , Leishmaniose Cutânea/prevenção & controle , Adolescente , Adulto , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Hábitos , Humanos , Renda , Inseticidas , Leishmania braziliensis , Leishmaniose Cutânea/epidemiologia , Controle de Mosquitos/métodos , Fatores Socioeconômicos , Inquéritos e Questionários
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