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1.
Auton Neurosci ; 246: 103073, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36736078

RESUMO

AIMS: In rats, stress-induced hyperthermia caused by social interaction depends on brown adipose tissue (BAT) thermogenesis and peripheral vasoconstriction. However, the peripheral mechanisms responsible for regulating the level of hyperthermia during social stress are still unknown. The transient receptor potential vanilloid 1 (TRPV1) subfamily, expressed in sensory and visceral neurons, can serve as a thermoreceptor. Here, we tested the hypothesis that the abdominal TRPV1 is essential in regulating stress-induced hyperthermia during social stress. MAIN METHODS: Male Wistar rats received an intraperitoneal injection of Resiniferatoxin (RTX) - an ultra-potent capsaicin analog, (i.e., to desensitize the TRPV1 channels) or vehicle. Seven days later, we evaluated the effects of abdominal TRPV1 channels desensitization on core body temperature (CBT), brown adipose tissue (BAT) temperature, tail skin temperature, and heart rate (HR) of rats subjected to a social stress protocol. KEY FINDINGS: We found abdominal TRPV1 desensitization increased CBT and BAT temperature but did not change tail skin temperature and HR during rest. However, under social stress, we found that abdominal TRPV1 desensitization heightened the increase in CBT and BAT caused by stress. Also, it abolished the increase in tail skin temperature that occurs during and after social stress. TRPV1 desensitization also delayed the HR recovery after the exposure to the social stress. SIGNIFICANCE: These results show that abdominal TRPV1 channels desensitization heightens stress-induced hyperthermia, causing heat dissipation during and after social stress, enabling optimal thermal control during social encounters.


Assuntos
Hipertermia Induzida , Canais de Cátion TRPV , Animais , Masculino , Ratos , Capsaicina/farmacologia , Ratos Sprague-Dawley , Ratos Wistar , Canais de Cátion TRPV/fisiologia
2.
Int J Environ Sci Technol (Tehran) ; 20(3): 2797-2818, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35529589

RESUMO

The Covid-19 pandemic has negatively disrupted the way our economy and society functions. Nonetheless, there have also been some positive externalities of the pandemic on the environment. This paper aims to evaluate the concentration of nitrogen dioxide in Brazilian metropolitan regions after the policies adopted to confront Covid-19. In terms of methodological approach, the study employs cross-sectional quantitative analyses to compare the period of 36 days, i.e., 12 March to 16 April-before (in 2019) and after (in 2020) the pandemic declaration. The data were obtained from the Sentinel 5-P low-Earth polar satellite concerning Brazilian metropolitan regions (n = 24). Thorough spatial and statistical analyses were undertaken to identify the pre- and during pandemic nitrogen dioxide concentrations. Complementarily, Spearman's correlation test was performed with variables that impact air quality. The study results a fall in nitrogen dioxide concentration levels in 21 of the 24 metropolitan regions which was observed. The Spearman's correlation coefficient between the nitrogen dioxide variation and the vehicle density was 0.485, at a significance level of 0.05. With these findings in mind, the paper advocates that while the pandemic has a significant negative consequence on the health of population globally, a series of measures that result in a new social organization directly interfere in the reduction of air pollution that contributes to the quality of the air we breathe.

3.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 513-516, Mar.-Apr. 2021. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1248925

RESUMO

A doxorrubicina (dox) é um medicamento antineoplásico que induz cardiotoxicidade por estresse oxidativo. Os flavonoides são antioxidantes extraídos de plantas como Camellia sinensis e Arrabidaea chica (Fridericia chica). Esta pesquisa objetivou avaliar efeitos protetores do extrato de A. chica (AC), comparado ao de C. sinensis (CS), frente ao estresse oxidativo induzido pela dox, no coração. Cardiomiócitos e células neoplásicas MDA-MB 231 foram incubados com AC e CS. Depois, adicionou-se dox e avaliaram-se taxas de viabilidade e morte celular. A citometria de fluxo para o ensaio de iodeto de propídeo (IP) em cardiomiócitos mostrou as seguintes taxas de morte celular: controle 53%; dox 78% (maior que controle, P=0,015); AC_12,5µg/mL + dox 65% (menor que dox, P=0,031); AC_25µg/mL + dox 62% (menor que dox, P=0,028); AC_50µg/mL + dox 63% (menor que dox, P=0,030); CS_12,5µg/mL + dox 71% (menor que dox, P=0,040); CS_25µg/ml + dox 69% (menor que dox, P=0,037); CS_50µg/mL + dox 74% (menor que dox, P=0,044). Resultados das células MDA-MB 231 mostraram que nenhum extrato interferiu na atividade antitumoral da dox. Os dados de IP foram corroborados pelos de MTT. Este estudo reporta promissora utilização de A. chica na prevenção da cardiotoxicidade induzida pela dox.(AU)


Assuntos
Animais , Ratos , Extratos Vegetais/uso terapêutico , Doxorrubicina , Bignoniaceae/química , Cardiotoxicidade/terapia , Cardiotoxicidade/veterinária , Plantas Medicinais , Flavonoides/uso terapêutico
4.
J Plast Reconstr Aesthet Surg ; 74(2): 364-369, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32888861

RESUMO

INTRODUCTION: With the emergence of blunt-tipped microcannulas, there is a hypothesis that these could cause less damage and reduce pain as compared to conventional sharp needles in eyelid surgery. The purpose is to determine whether an 18G blunt-tipped cannula can be better than a 26G needle. METHODS: This prospective, observer-blinded, randomized clinical trial was conducted from June 2017 to December 2018. Sixty-eight patients were randomized to receive local anesthesia injections for upper blepharoplasty. Infiltration was performed by using a 26-gauge sharp needle on one side and on the other side, infiltration was performed by using an 18-gauge stainless-steel blunt-tipped microcannula. A numeric rating scale (NRS) from 0 to 10 was used to blindly assess pain in patients receiving anesthesia injections with both needle types. Photographs of the eyelids of each patient were taken in five different periods and used by three blinded observers to identify bruise or ecchymoses. RESULTS: A total of 136 eyelid operations were performed. There was no statistically significant difference when both groups were compared; however, the average score of pain was higher in patients taking the infiltration through the needle (2.85 versus 2.50). Regarding the evaluation of bruising and ecchymoses, the results showed that, in the five periods evaluated, there was no statistical difference in bruising and ecchymosis in the eyelids when taking the infiltration through a sharp needle when compared with that of the eyelids taking infiltration through a (blunt-tipped) microcannula. CONCLUSION: The evaluation of the blunt-tipped microcannula showed a lower pain score mean than that obtained for the sharp needle (2.5 versus 2.85) (p > 0.05). There was no statistically significant difference in the bruising and ecchymosis courses.


Assuntos
Anestesia Local/instrumentação , Blefaroplastia , Cânula/efeitos adversos , Contusões/prevenção & controle , Equimose/prevenção & controle , Agulhas/efeitos adversos , Dor Processual/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Local/métodos , Contusões/diagnóstico , Contusões/epidemiologia , Contusões/etiologia , Método Duplo-Cego , Equimose/diagnóstico , Equimose/epidemiologia , Equimose/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Processual/diagnóstico , Dor Processual/epidemiologia , Dor Processual/etiologia , Estudos Prospectivos
6.
Brain Behav Immun ; 80: 500-511, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31022457

RESUMO

Overweight and obesity are a worldwide pandemic affecting billions of people. These conditions have been associated with a chronic low-grade inflammatory state that is recognized as a risk factor for a range of somatic diseases as well as neurodevelopmental disorders, anxiety disorders, trauma- and stressor-related disorders, and affective disorders. We previously reported that the ingestion of a high-fat diet (HFD; 45% fat kcal/g) for nine weeks was capable of inducing obesity in rats in association with increased reactivity to stress and increased anxiety-related defensive behavior. In this study, we conducted a nine-week diet protocol to induce obesity in rats, followed by investigation of anxiety-related defensive behavioral responses using the elevated T-maze (ETM), numbers of FOS-immunoreactive cells after exposure of rats to the avoidance or escape task of the ETM, and neuroinflammatory cytokine expression in hypothalamic and amygdaloid nuclei. In addition, we investigated stress-induced cutaneous thermoregulatory responses during exposure to an open-field (OF). Here we demonstrated that nine weeks of HFD intake induced obesity, in association with increased abdominal fat pad weight, increased anxiety-related defensive behavioral responses, and increased proinflammatory cytokines in hypothalamic and amygdaloid nuclei. In addition, HFD exposure altered avoidance- or escape task-induced FOS-immunoreactivity within brain structures involved in control of neuroendocrine, autonomic, and behavioral responses to aversive stimuli, including the basolateral amygdala (BLA) and dorsomedial (DMH), paraventricular (PVN) and ventromedial (VMH) hypothalamic nuclei. Furthermore, rats exposed to HFD, relative to control diet-fed rats, responded with increased tail skin temperature at baseline and throughout exposure to an open-field apparatus. These data are consistent with the hypothesis that HFD induces neuroinflammation, alters excitability of brain nuclei controlling neuroendocrine, autonomic, and behavioral responses to stressful stimuli, and enhances stress reactivity and anxiety-like defensive behavioral responses.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Dieta Hiperlipídica/efeitos adversos , Neuroimunomodulação/fisiologia , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/metabolismo , Transtornos de Ansiedade/metabolismo , Corticosterona , Hipotálamo/metabolismo , Masculino , Obesidade , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Aumento de Peso
7.
Braz. j. biol ; 78(2): 306-310, May-Aug. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-888877

RESUMO

Abstract The goal of this study was to analyze cytotoxicity, genotoxicity and mutagenicity to bone marrow cells of mice of nature identical synthetic flavorings, passion fruit and strawberry, and artificial synthetic flavorings, vanilla, chocolate, tutti-frutti and cookie, at doses 0.5; 1.0; 2.0; 5.0 and 10.0 mL/kg. The additives were given to the animals by gavage in a single daily application for seven days. Data were subjected to analysis of variance (ANOVA) followed by post Tukey's post hoc test, p <0.05. Animals treated with 2.0; 5.0 and 10.0 mL/Kg of flavorings chocolate, strawberry and cookie, and 5.0 and 10.0 mL/Kg of flavorings vanilla and passion fruit died on the fifth and sixth day of the experiment, respectively. The doses 0.5 and 1.0 mL/Kg of the six additives significantly reduced erythropoiesis in the examined tissue. Also, treatments 0.5 and 1.0 mL/Kg of chocolate, and 1.0 mL/Kg of strawberry and biscuit induced the formation of micronuclei in the bone marrow erythrocytes, at a significant frequency. Therefore, under the study conditions, the six microingredients analyzed were cytotoxic and genotoxic, and additives strawberry, chocolate and cookie were also mutagenic in at least one of the evaluated doses.


Resumo Os aromatizantes são essenciais para a indústria na confecção de alimentos industrializados. Porém, pouco se sabe sobre o potencial tóxico desses microingredientes alimentares. Dessa forma, objetivou-se neste trabalho analisar, em células de medula óssea de camundongos, a citotoxicidade, genotoxicidade e mutagenicidade de aromatizantes alimentares sintéticos idênticos ao natural, de maracujá e morango, e artificiais, de baunilha, chocolate, tutti-frutti e biscoito, nas doses 0,5; 1,0; 2,0; 5,0 e 10,0 mL/Kg. Os aditivos foram administrados aos animais via gavagem em aplicação diária única durante sete dias. Os dados obtidos foram submetidos ao procedimento estatístico ANOVA com pós teste de Tukey, com p < 0.05. Os animais tratados com 2,0; 5,0 e 10,0 mL/Kg dos aromatizantes de chocolate, morango e biscoito, e 5,0 e 10,0 mL/Kg dos aromatizantes de baunilha e maracujá vieram a óbito no quinto e sexto dia de experimento, respectivamente. As doses 0,5 e 1,0 mL/Kg dos seis aditivos reduziram significativamente a eritropoiese do tecido analisado. Ainda, os tratamentos 0,5 e 1,0 mL/kg de chocolate, e 1,0 mL/Kg de morango e biscoito induziram a formação de micronúcleos aos eritrócitos de medula em frequência significante. Portanto, nas condições de estudo estabelecidas, os seis microingredientes analisados foram citotóxico e genotóxicos, e os aditivos de morango, chocolate e biscoito também foram mutagênicos em pelo menos uma das doses avaliadas.


Assuntos
Animais , Camundongos , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Aromatizantes/toxicidade , Citotoxinas/toxicidade , Mutagênicos/toxicidade
8.
Braz J Biol ; 78(2): 306-310, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28832835

RESUMO

The goal of this study was to analyze cytotoxicity, genotoxicity and mutagenicity to bone marrow cells of mice of nature identical synthetic flavorings, passion fruit and strawberry, and artificial synthetic flavorings, vanilla, chocolate, tutti-frutti and cookie, at doses 0.5; 1.0; 2.0; 5.0 and 10.0 mL/kg. The additives were given to the animals by gavage in a single daily application for seven days. Data were subjected to analysis of variance (ANOVA) followed by post Tukey's post hoc test, p <0.05. Animals treated with 2.0; 5.0 and 10.0 mL/Kg of flavorings chocolate, strawberry and cookie, and 5.0 and 10.0 mL/Kg of flavorings vanilla and passion fruit died on the fifth and sixth day of the experiment, respectively. The doses 0.5 and 1.0 mL/Kg of the six additives significantly reduced erythropoiesis in the examined tissue. Also, treatments 0.5 and 1.0 mL/Kg of chocolate, and 1.0 mL/Kg of strawberry and biscuit induced the formation of micronuclei in the bone marrow erythrocytes, at a significant frequency. Therefore, under the study conditions, the six microingredients analyzed were cytotoxic and genotoxic, and additives strawberry, chocolate and cookie were also mutagenic in at least one of the evaluated doses.


Assuntos
Células da Medula Óssea , Aromatizantes/toxicidade , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Citotoxinas/toxicidade , Camundongos , Mutagênicos/toxicidade
9.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1557-1564, set.-out. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-947384

RESUMO

Foram estudados diferentes diluentes no processo de refrigeração do sêmen da garoupa-verdadeira. Inicialmente, a taxa e a duração da motilidade e a concentração espermática foram avaliadas, caracterizando a qualidade do sêmen fresco. Para os testes de refrigeração a 4ºC, diferentes diluentes foram testados em atmosfera normal e modificada (100% oxigênio). O sêmen fresco apresentou concentração espermática de 3,1±0,2 x 109 células mL-1, motilidade média de 90%, permanecendo móvel, em média, por 3.060 segundos. No experimento de refrigeração, a taxa e a duração média da motilidade foram mantidas adequadas durante 144 horas para o diluente A (70%; 3100 segundos) em atmosfera normal. Na atmosfera modificada, a qualidade do sêmen caiu drasticamente durante as primeiras 24 horas, independentemente do diluente empregado, não propiciando vantagem em sua utilização. A refrigeração do sêmen da garoupa-verdadeira permite manter por até 144 horas uma apropriada qualidade espermática.(AU)


This study aimed to evaluate different extenders in refrigerated storage of dusky grouper sperm. Initially, motility rate, motility time, and sperm density were analyzed to characterize the fresh sperm quality. Different diluents were used in the refrigerated storage sperm at 4ºC in normal atmosphere and modified atmosphere (100% oxygen). The fresh sperm has a spermatozoa density of 3.1±0.2 x 109 spermatozoa mL-1, motility rate 90% and motility time of 3,060 seconds. In the experiment of refrigerated storage, the motility rate and the motility time were maintained appropriate for 144 hours for the extender A (70%; 3,100 seconds) in normal atmosphere. In the modified atmosphere, the sperm quality decreased drastically during the first 24 hours, independently of the diluent used, not propitiating advantages. The refrigerated sperm of dusky grouper is a viable alternative for the short-term storage, being possible, to maintain for up to 144 hours an appropriate sperm viability.(AU)


Assuntos
Animais , Masculino , Pesqueiros/análise , Perciformes/embriologia , Preservação do Sêmen/veterinária
10.
Genet Mol Res ; 16(2)2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28510257

RESUMO

Water deficit is the main reason for instability in the context of soybean culture. The development of strategies for the selection of more tolerant genotypes is necessary. These strategies include the use of polyethylene glycol 6000 solutions (PEG-6000) for conducting the germination test under conditions of water restriction. Thus, the objective of this study was to determine the osmotic potential and the main characteristics that promote the discrimination of soybean genotypes with regard to water stress tolerance during germination and the vigor test. Thirteen soybean cultivars were used. The seeds were allowed to germinate on sheets of germitest paper moistened in solution with PEG-6000, simulating different levels of water availability, which is expressed as osmotic potential (0.0, -0.2, -0.4, and -0.6 MPa). We assessed germination, length, and dry mass for seedlings and seeds, as well as reserve dynamics. Germination and variables related to the dynamics of reservation have great influence on the expression of variability in environments under stress. Among the different osmotic potentials, the -0.2 MPa was the most efficient for the expression of genetic variability among the cultivars. Conducting the germination test with PEG-6000 solution to -0.2 MPa was efficient for selecting soybean cultivars tolerant to water stress. This was accomplished by evaluating the percentage of germination, along with variables related to the dynamics of reservation.


Assuntos
Secas , Genótipo , Germinação/genética , Glycine max/genética , Melhoramento Vegetal/métodos , Seleção Genética , Adaptação Fisiológica , Pressão Osmótica , Glycine max/crescimento & desenvolvimento , Glycine max/fisiologia
11.
N Biotechnol ; 39(Pt A): 90-98, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27343427

RESUMO

Biorefineries have the potential to meet a significant part of the growing demand for energy, fuels, chemicals and materials worldwide. Indeed, the bio-based industry is expected to play a major role in energy security and climate change mitigation during the 21th century. Despite this, there are challenges related to resource consumption, processing optimization and waste minimization that still need to be overcome. In this context, microalgae appear as a promising non-edible feedstock with advantages over traditional land crops, such as high productivity, continuous harvesting throughout the year and minimal problems regarding land use. Importantly, both cultivation and microalgae processing can take place at the same site, which increases the possibilities for process integration and a reduction in logistic costs at biorefinery facilities. This review describes the actual scenario for microalgae biorefineries integration to the biofuels and petrochemical industries in Brazil, while highlighting the major challenges and recent advances in microalgae large-scale production.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Microalgas/metabolismo , Biomassa , Brasil
12.
Rev Sci Instrum ; 88(12): 125005, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29289169

RESUMO

Signal attenuation limits the operating range in wireless communications and location. To solve the reduced range problem, we can use low-frequency signals in combination with magnetic sensing. We propose the use of an optically pumped magnetometer as a sensor and realize a proof-of-principle detection of binary phase shift keying (BPSK) modulated signals. We demonstrate a ranging enhancement by exploiting both the magnetometer's intrinsic sensitivity of below 1 pT/Hz1/2 and its 1 kHz operating bandwidth through the use of BPSK signals.

13.
Genet Mol Res ; 15(4)2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27886345

RESUMO

Slow seed coat darkening is desirable in common bean cultivars and genetic parameters are important to define breeding strategies. The aims of this study were to estimate genetic parameters for plant architecture, grain yield, grain size, and seed-coat darkening in common bean; identify any genetic association among these traits; and select lines that associate desirable phenotypes for these traits. Three experiments were set up in the winter 2012 growing season, in Santo Antônio de Goiás and Brasília, Brazil, including 220 lines obtained from four segregating populations and five parents. A triple lattice 15 x 15 experimental design was used. The traits evaluated were plant architecture, grain yield, grain size, and seed-coat darkening. Analyses of variance were carried out and genetic parameters such as heritability, gain expected from selection, and correlations, were estimated. For selection of superior lines, a "weight-free and parameter-free" index was used. The estimates of genetic variance, heritability, and gain expected from selection were high, indicating good possibility for success in selection of the four traits. The genotype x environment interaction was proportionally more important for yield than for the other traits. There was no strong genetic correlation observed among the four traits, which indicates the possibility of selection of superior lines with many traits. Considering simultaneous selection, it was not possible to join high genetic gains for the four traits. Forty-four lines that combined high yield, more upright plant architecture, slow darkening grains, and commercial grade size were selected.


Assuntos
Phaseolus/genética , Característica Quantitativa Herdável , Sementes/genética , Cruzamentos Genéticos , Variação Genética , Genótipo , Locos de Características Quantitativas , Seleção Genética
14.
Braz J Med Biol Res ; 48(10): 895-901, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26445332

RESUMO

According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.


Assuntos
Lesões por Radiação/diagnóstico , Liberação Nociva de Radioativos/estatística & dados numéricos , Radiometria/métodos , Pele/efeitos da radiação , Brasil/epidemiologia , Chile/epidemiologia , Espectroscopia de Ressonância de Spin Eletrônica , Traumatismos dos Dedos/etiologia , Traumatismos da Mão/etiologia , Humanos , Medições Luminescentes , Doses de Radiação , Exposição à Radiação/efeitos adversos , Lesões por Radiação/epidemiologia
15.
Braz. j. med. biol. res ; 48(10): 895-901, Oct. 2015. tab
Artigo em Inglês | LILACS | ID: lil-761598

RESUMO

According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.


Assuntos
Humanos , Lesões por Radiação/diagnóstico , Liberação Nociva de Radioativos/estatística & dados numéricos , Radiometria/métodos , Pele/efeitos da radiação , Brasil/epidemiologia , Chile/epidemiologia , Espectroscopia de Ressonância de Spin Eletrônica , Traumatismos dos Dedos/etiologia , Traumatismos da Mão/etiologia , Medições Luminescentes , Doses de Radiação , Exposição à Radiação/efeitos adversos , Lesões por Radiação/epidemiologia
16.
Arq. bras. med. vet. zootec ; 67(3): 698-706, May-Jun/2015. tab, graf
Artigo em Português | LILACS | ID: lil-753931

RESUMO

A presente pesquisa analisou o efeito da iluminação constante sobre a estrutura placentária de ratas, abordando parâmetros morfológicos, morfométricos e histoquímicos. Vinte ratas albinas foram submetidas aos seguintes tratamentos: 12hL/12hE por 60 dias, e acasaladas em seguida (GI); ausência de luz por 60 dias, e acasaladas em seguida (GII); iluminação constante por 60 dias, e acasaladas em seguida (GIII); iluminação constante por 60 dias, acasaladas em seguida e tratadas com melatonina (GIV). O estímulo luminoso foi em torno de 400 lux. A melatonina foi administrada na água (400mg/mL de etanol). Os resultados mostraram que histologicamente o GII apresentou vacuolização das células do trofospongio. Morfometricamente, o GIII apresentou camada do labirinto com redução no número de trofoblastos sinciciais e maior vascularização materno-fetal, hiperplasia e hipertrofia das células trofoblásticas gigantes, uma maior média da área total do disco placentário; porém, na camada de trofospongio, as células trofoblásticas e trofoblastos sinciciais não diferiram nos grupos experimentais. As placentas do GIV foram semelhantes às do GI. Histoquimicamente não houve alterações nas fibras colágenas, elásticas, reticulares e glicosaminoglicanas ácidas. Em conclusão, a iluminação constante promove alterações morfológicas e morfométricas na placenta de ratas, podendo acarretar redução funcional e restrições ao crescimento fetal. Essas alterações são abolidas pela reposição de melatonina.


This study examined the effect of constant illumination on the placental structure of rats, addressing morphological, morphometric and immunohistochemical parameters. 20 albino rats were subjected to the following treatments: GI-12hL/12hE for 60 days and then mated; GII- dark for 60 days and then mated; GIII- constant illumination for 60 days and then mated and GIV- constant light for 60 days, mated and then treated with melatonin. The light stimulus was around 400 lux. Melatonin was administered in water (400 mg / ml ethanol). The results showed that GII had histologically trofospongio vacuolization of cells. Morphometrically, GIII presented a labyrinth layer reduction in the number of syncytial trophoblasts and greater maternal-fetal vasculature, hyperplasia and hypertrophy of trophoblast giant cells, a higher average of the total area of the placenta disk, but in the trofospongio layer, the trophoblast cells and syncytial trophoblasts did not differ between experimental groups. The placentas in GIV were similar to GI. Histochemically there were no changes in the collagen and elastic fibers, reticular and acidic glycosaminoglycans. In conclusion, the constant lighting promotes morphological and morphometric changes in the placenta in rats and may lead to functional reduction and restrictions on fetal growth. These changes are abolished by the melatonin replacement.


Assuntos
Animais , Feminino , Gravidez , Ratos , Iluminação/métodos , Placenta/anatomia & histologia , Desenvolvimento Fetal , Melatonina/análise , Fotoperíodo
17.
Neurotoxicology ; 47: 54-61, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25616225

RESUMO

The scorpion envenoming syndrome is an important worldwide public health problem due to its high incidence and potential severity of symptoms. Some studies address the high sensitivity of the central nervous system to this toxin action. It is known that cardiorespiratory manifestations involve the activation of the autonomic nervous system. However, the origin of this modulation remains unclear. Considering the important participation of the dorsomedial hypotalamus (DMH) in the cardiovascular responses during emergencial situations, the aim of this work is to investigate the involvement of the DMH on cardiovascular responses induced by intracerebroventricular (icv) injection of Tityustoxin (TsTX, a α-type toxin extracted from the Tityus serrulatus scorpion venom). Urethane-anaesthetized male Wistar rats (n=30) were treated with PBS, muscimol or ionotropic glutamate receptor antagonists, bilaterally in DMH and later, with an icv injection of TsTX, or treated only with PBS in both regions. TsTX evoked a marked increase in mean arterial pressure and heart rate in all control rats. Interestingly, injection of muscimol, a GABAA receptor agonist, did not change the pressor and tachycardic responses evoked by TsTX. Remarkably, the injection ionotropic glutamate receptors antagonists in DMH abolished the pressor and the tachycardic response evoked by TsTX. Our data suggest that the central circuit recruited by TsTX, whose activation results in an array of physiological and behavioral alterations, depend on the activation of DMH ionotropic glutamate receptors. Moreover, our data provide new insights on the central mechanisms involved in the development of symptoms in the severe scorpion envenomation syndrome.


Assuntos
Núcleo Hipotalâmico Dorsomedial/efeitos dos fármacos , Hipertensão/metabolismo , Receptores Ionotrópicos de Glutamato/metabolismo , Venenos de Escorpião/toxicidade , Taquicardia/metabolismo , Animais , Pressão Arterial/efeitos dos fármacos , Núcleo Hipotalâmico Dorsomedial/metabolismo , Agonistas de Receptores de GABA-A , Hipertensão/induzido quimicamente , Injeções Intraventriculares , Masculino , Ratos , Ratos Wistar , Receptores de GABA-A/metabolismo , Receptores Ionotrópicos de Glutamato/antagonistas & inibidores , Venenos de Escorpião/administração & dosagem , Taquicardia/induzido quimicamente
18.
Genet Mol Res ; 14(4): 18965-73, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782546

RESUMO

The aim of this case-control study was to obtain a comprehensive panel of genetic polymorphisms present only in genes (cytochrome P-450 1A1--CYP1A1 and catechol-O-methyl transferase--COMT) within the metabolic pathway of sex steroids and determine their possible associations with the presence or absence of cervical cancer. Genotypes of 222 women were analyzed: a) 81 with cancer of the cervix treated at the Cancer Hospital Alfredo Abram, between June 2012 and May 2013, with diagnosis confirmed surgically and/or through histomorphological examination; and b) 141 healthy women who assisted at the Endocrine Gynecology and Climacteric Ambulatory, Department of Gynecology, UNIFESP-EPM. These polymorphisms were detected by polymerase chain reaction amplification-restriction fragment length polymorphism analysis and visualized on 3% agarose gels stained with ethidium bromide. We found a significant association between the frequency of the CYP1A1 polymorphism and the development of cervical cancer. A statistical difference was observed between patient and control groups for CYP1A1 polymorphism genotype distributions (P < 0.05). However, no significant differences were found in the COMT gene polymorphism genotype distributions between the patient and control groups (P > 0.05) or between other risk variables analyzed. The CYP1A1 gene involved in the metabolic pathway of sex steroids might influence the emergence of pathological conditions such as cervical cancer in women who carry a mutated allele, and result in 1.80 and 13.46 times increased risk for women with heterozygous or homozygous mutated genotypes, respectively.


Assuntos
Catecol O-Metiltransferase/genética , Citocromo P-450 CYP1A1/genética , Neoplasias do Colo do Útero/genética , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos
19.
Genet Mol Res ; 13(3): 6486-96, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25158267

RESUMO

The maintenance of the light color of the grains of carioca beans is a requirement for the development of new cultivars of common beans because it enables the storage of grains for long periods so that they may be traded at a proper opportunity. Crosses of cultivar BRSMG Madrepérola, which presents slow grain darkening, were made to 10 elite lines presenting normal darkening to obtain information about the genetic control of the trait and estimates of phenotypic and genotypic parameters. Progenies at the tegument generations F3 and F4 and their parents were evaluated at the locations of Santo Antônio de Goiás and Ponta Grossa at 71, 106, and 155 days of storage for seed-coat darkening using a rank of scores ranging from 1 (very light colored grains) to 5 (very dark colored grains). Genotypic and phenotypic variances and broad-sense heritabilities were estimated for each population. The segregation ratios were subjected to the chi-square test to establish the genetic control. Some populations did not present consistent patterns of genetic control, while others presented monogenic or double-recessive digenic segregation, indicating that the trait is controlled by few genes. Six segregant populations were identified with both low means for darkening and high expected gain under selection. Despite the strong environmental influence on the expression of the traits and the occurrence of the genotype by environment interaction, the estimates of genotypic and phenotypic parameters indicate the possibility of successful selection to develop lines with slow seed-coat darkening.


Assuntos
Genes de Plantas , Phaseolus/genética , Característica Quantitativa Herdável , Sementes/genética , Cor , Cruzamentos Genéticos , Armazenamento de Alimentos , Interação Gene-Ambiente , Genótipo , Phaseolus/anatomia & histologia , Fenótipo , Sementes/anatomia & histologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-25019787

RESUMO

We investigate the structural properties of a small binary system of dusty plasma subjected to an anisotropic external confinement. We have found that the ground state can form various symmetrical configurations, which generally correspond to variations of a multiple-ring structure. The presence of such structures is given through a detailed phase diagram constructed for the systems with N=18 and 24 particles. Furthermore, we show that the configurations of multiple rings can present a persistent behavior for the case in which the number of less-charged particles is equal to a multiple of the number of particles per ring. Finally, we discuss the main characteristics of the transitions of first and second orders since these are related to the main configurational changes of the ground states.


Assuntos
Modelos Químicos , Gases em Plasma/química , Eletricidade Estática , Anisotropia , Simulação por Computador , Transição de Fase
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