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1.
Morphologie ; 108(362): 100784, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38696841

RESUMEN

Histology is part of the curricular base of all health courses, being the basis for understanding the composition of all tissues in the human body. Over the years, more and more technologies have entered the academic environment, with the aim of improving the teaching and learning process. Thus, the objective of this work was to conduct a systematic review on the use of digital technologies in teaching histology. The PICo strategy was used to develop the guiding question and the results were presented in a Prisma Flow. The following platforms were used to search for articles: PubMed, Embase. Web of Science, Science Direct, Medline, Scielo, Periódicos CAPES and LILACS, Open Gray and Google Scholar, with a time limit between 2012 and 2022. The results showed that this area is still little explored, with there not being a wide range of technologies being used and applied in teaching, with gamification and virtual microscopy being the most applied. However, it was realized that the use of these technologies can improve student performance and increase their interest in the subject. Therefore, these tools are great methods to reduce difficulties and encourage the development of a more receptive environment for the histology teaching and learning process.


Asunto(s)
Histología , Humanos , Instrucción por Computador/métodos , Curriculum , Tecnología Digital , Tecnología Educacional/tendencias , Histología/educación , Aprendizaje , Microscopía/métodos , Enseñanza
2.
Rev. Soc. Cardiol. Estado São Paulo, Supl. ; 34(2B): 199-199, abr-jun. 2024. ilus
Artículo en Portugués | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1562000

RESUMEN

INTRODUÇÃO: A elevação do segmento ST com morfologia em lápide foi descrita primeiramente por Wimalaratna em 1993, tem prevalência descrita na literatura entre 10 e 26,1% das oclusões coronarianas agudas com supradesnivelamento do segmento ST (SCA-CSST). No padrão em lápide, o segmento ST se funde com a onda T, e por vezes a torna indistinguível. Além disso, assemelha-se a um potencial monofásico devido à união do complexo QRS com a onda T e pode apresentar infradesnivelamento de ST em paredes opostas como alterações recíprocas. O objetivo deste trabalho é relatar um caso clínico de SCA-CSST com morfologia em lápide. DESCRIÇÃO: Paciente de meia idade, histórico de hipertensão, dislipidemia, obesidade grau I e ex-tabagismo (10 maços/ano). Chega ao pronto-socorro por dor torácica retroesternal atípica, iniciada há um dia. Histórico familiar de doença arterial coronariana precoce. O exame físico não apresentava alterações e o eletrocardiograma (ECG) inicial não demonstrava alterações sugestivas de isquemia. Após solicitação dos exames iniciais, apresentou súbita piora da dor torácica, de forte intensidade, sendo realizado novo ECG com evidência de Supra-ST em padrão de lápide. Transferido à sala de hemodinâmica, apresentava sinais de baixo débito e evoluiu com parada cardiorrespiratória (PCR). Iniciado protocolo de ressuscitação cardiopulmonar (RCP) e procedida angiografia, observando-se oclusão total em terço proximal da artéria descendente anterior. Realizada angioplastia, apresentou retorno à circulação espontânea após dois minutos da reperfusão. Devido à gravidade do quadro de oclusão coronariana aguda levando a choque cardiogênico, refratário à elevadas doses de drogas vasoativas, foi iniciado suporte circulatório com balão intra-aórtico. Em detrimento de todas as medidas instituídas, evolui com nova PCR que o levou a óbito mesmo após 45 minutos de nova tentativa de RCP. CONCLUSÃO: A apresentação eletrocardiográfica do padrão morfológico em lápide do segmento ST no contexto do infarto agudo do miocárdio está associada a uma extensa lesão coronariana, maior liberação de biomarcadores cardíacos e desfechos clínicos desfavoráveis. Portanto, sua identificação precoce e a implementação de medidas terapêuticas intensivas são cruciais para melhorar os resultados clínicos e reduzir a morbimortalidade associada a essa condição.


Asunto(s)
Persona de Mediana Edad , Paro Cardíaco
3.
Braz J Biol ; 84: e273999, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451628

RESUMEN

The production of seedlings of the passion fruit tree, usually, is sexual, and the seeds are not uniform in the seedling emergence, and soaking treatments of seeds can provide faster and more uniform germination. It was aimed to study the action of plant growth regulators and the mobilization of reserves in the stages of soaking of yellow passion fruit seeds. The seeds were soaked for five hours in solutions containing plant growth regulators, in a completely randomized design, in a factorial 8 x 4, with four replications. The first factor corresponds to eight plant growth regulators: T1 - distilled water (control); T2 - 6-benzylaminepurine ​​500 mg L-1; T3 - 4-(3-indolyl) butyric acid 500 mg L-1; T4 - gibberellic acid 500 mg L-1; T5 - spermine 250 mg L-1; T6 - spermine 750 mg L-1; T7 - spermidine 750 mg L-1; T8 - spermidine 1250 mg L-1; and the second factor, to the four soaking times: zero, four, 72 and 120 hours, corresponding, respectively, to the dry seed, and to phases I, II, and III of the imbibition curve. It was evaluated the biochemical composition of seeds (lipids, soluble sugars and starch). The seeds showed accumulation of lipids in phase III; the content of soluble sugars increased in phase I and decreased in phase II. The starch content increased until the phase II and decreased in phase III. Starch is the main reserve in the seeds and the main source of energy used in phase III; soaking the seeds in polyamines generates an accumulation of lipids in the seeds and soaking in plant growth regulators increases the burning of starch.


Asunto(s)
Passiflora , Reguladores del Crecimiento de las Plantas , Reguladores del Crecimiento de las Plantas/farmacología , Frutas , Espermidina , Espermina , Ácido Butírico , Plantones , Almidón , Azúcares
4.
Braz J Biol ; 83: e277437, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422256

RESUMEN

The use of residues from coffee production to obtain biochar is a sustainable approach, which aims to minimize the environmental impact of these materials. In this study, the effect of adding coffee straw biochar on the physiological quality of lettuce and sorghum seeds was investigated. Thus, the objective of this work was to study the effect of adding different concentrations of coffee biochar in the substrate composition on the physiological quality of lettuce (Lactuca sativa) and sorghum (Sorghum bicolor) seeds. The experimental design used was completely randomized, with five concentrations of biochar (0; 7.5; 15; 30 and 60%), conducted with four replications of 25 seeds. The use of biochar in the concentrations studied does not provide an increase in the average germination percentage and vigor of lettuce and sorghum seeds. The increase in the concentration of biochar caused less seed vigor, suggesting a toxic effect. For seed germination, there was no significant difference between lettuce and sorghum species, regardless of treatment. For the germination speed index, sorghum seeds have higher means, except for the treatment with the addition of 15% coffee straw biochar. Lettuce seeds have higher shoot length averages, except for treatment with 100% commercial substrate. The sorghum seeds have higher mean root length and dry mass than lettuce, regardless of the treatment.


Asunto(s)
Carbón Orgánico , Germinación , Sorghum , Café , Grano Comestible , Lactuca , Semillas/fisiología
5.
Braz. j. biol ; 84: e251883, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1350313

RESUMEN

Abstract The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.


Resumo O menor teor de lignina em espécies de plantas com potencial energético resulta na maior facilidade de quebra da celulose, disponibilizando glicose para geração de etanol. Porém, maiores teores de lignina representa um fator de resistência ao ataque de insetos. O objetivo deste trabalho foi avaliar como importantes pragas do sorgo energia, Diatraea saccharalis e Spodoptera frugiperda, se comportam quanto à alimentação e desempenho em sorgo bmr-6, um genótipo mutante com menor concentração de lignina. Foram realizados experimentos em laboratório e casa de vegetação, avaliando o desenvolvimento destas pragas nos híbridos de sorgo biomassa bmr 007, 008, TX635 e seus respectivos genótipos isogênicos convencionais (sem o gene bmr). O teor de lignina foi maior nos híbridos não bmr, mas nos parâmetros avaliados nos insetos, houve variação entre os tratamentos, não sendo consistente em apenas um híbrido e nem por ser ou não bmr. A menor sobrevivência de S. frugiperda foi verificada no híbrido BR008 tanto bmr quanto não bmr. As notas de injúria por S. frugiperda no sorgo em casa de vegetação foram altas (>7) em todos os tratamentos. Para D. saccharalis, não houve diferença significativa para a sobrevivência larval em laboratório, mas em casa de vegetação o híbrido BR007 tanto bmr quanto não bmr proporcionaram maior sobrevivência. Diante da necessidade de diversificar a matriz energética e o fato de que não foi comprovada neste estudo maior suscetibilidade dos híbridos bmr a ambas as pragas, estes resultados são promissores para o cultivo desses híbridos de sorgo biomassa para produção de biocombustíveis.


Asunto(s)
Animales , Saccharum/genética , Sorghum/genética , Mariposas Nocturnas , Spodoptera , Larva
6.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469264

RESUMEN

Abstract The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.


Resumo O menor teor de lignina em espécies de plantas com potencial energético resulta na maior facilidade de quebra da celulose, disponibilizando glicose para geração de etanol. Porém, maiores teores de lignina representa um fator de resistência ao ataque de insetos. O objetivo deste trabalho foi avaliar como importantes pragas do sorgo energia, Diatraea saccharalis e Spodoptera frugiperda, se comportam quanto à alimentação e desempenho em sorgo bmr-6, um genótipo mutante com menor concentração de lignina. Foram realizados experimentos em laboratório e casa de vegetação, avaliando o desenvolvimento destas pragas nos híbridos de sorgo biomassa bmr 007, 008, TX635 e seus respectivos genótipos isogênicos convencionais (sem o gene bmr). O teor de lignina foi maior nos híbridos não bmr, mas nos parâmetros avaliados nos insetos, houve variação entre os tratamentos, não sendo consistente em apenas um híbrido e nem por ser ou não bmr. A menor sobrevivência de S. frugiperda foi verificada no híbrido BR008 tanto bmr quanto não bmr. As notas de injúria por S. frugiperda no sorgo em casa de vegetação foram altas (>7) em todos os tratamentos. Para D. saccharalis, não houve diferença significativa para a sobrevivência larval em laboratório, mas em casa de vegetação o híbrido BR007 tanto bmr quanto não bmr proporcionaram maior sobrevivência. Diante da necessidade de diversificar a matriz energética e o fato de que não foi comprovada neste estudo maior suscetibilidade dos híbridos bmr a ambas as pragas, estes resultados são promissores para o cultivo desses híbridos de sorgo biomassa para produção de biocombustíveis.

7.
Braz J Biol ; 83: e274888, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38055577

RESUMEN

Ateleia glazioveana Baill. is a pioneer, rustic and can be used for forest recovery. This work aimed to study the process of physiological maturation of this species. The research was carried out in the city of Alegre - ES, the trees were identified in the floral anthesis and accompanied during the filling of the fruits and development of the seeds until the complete maturation. The fruits were harvested at the following stages 7, 14, 21, 28, 35 and 42 days after anthesis, and characterized according to: morphometry, moisture, fresh and dry mass of fruits and seeds, germination, germination speed index, shoot and root length and dry mass of seedlings. The regression equations were adjusted for the main characteristics analyzed as a function of the harvest period. The point of physiological maturity of timbó occurred at 42 days after anthesis.


Asunto(s)
Fabaceae , Semillas , Germinación/fisiología , Plantones , Frutas
8.
Braz J Biol ; 83: e275338, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37970903

RESUMEN

Simultaneous analysis studies of several agronomic traits in cultivated plants make it possible to identify phenotypic and genotypic differences due to environmental variations, such as altitude. Therefore, the objective was to evaluate, through multivariate analysis of agronomic, physicochemical and physiological characters, passion fruit hybrids cultivated in different environments. The hybrids used were Gigante Amarelo, Rubi do Cerrado and Sol do Cerrado, cultivated in the southern region of Espírito Santo in four municipalities/environments: Marataízes (41 m), Jerônimo Monteiro (104 m), Alegre (711 m), and Ibitirama (1016 m). The agronomic characters of the plants, the physical-chemical characteristics of the fruits and the physical, biochemical and physiological qualities of the seeds were analyzed. The Singh method was used to determine the most important differentiating characters between hybrids growing in different environments. Based on these characters, a dissimilarity matrix was generated and a principal coordinate analysis was performed. It was observed that the pulp yield was influenced by altitude. The three hybrids showed greater performance in terms of agronomic characters at altitude (41 m) than at altitude (104 m). The Sol do Cerrado hybrid showed high performance in the physical-chemical characteristics of the fruits at altitude (104 m).


Asunto(s)
Frutas , Passiflora , Frutas/genética , Passiflora/genética , Semillas , Agricultura , Análisis Multivariante
9.
Cryo Letters ; 44(3): 151-159, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37883168

RESUMEN

BACKGROUND: Semen cryopreservation is a biotechnology used frequently in animal production; however, there are some obstacles, such as those caused by high levels of reactive oxygen species (ROS). Moringa oleifera (MO) is known as a potent source of antioxidants and might be an important adjuvant. OBJECTIVE: The objective of this study was to determine the effect of different concentrations of MO extract supplementation on goat semen cryopreservation efficiency. MATERIALS AND METHODS: Ejaculates (n=6) from four goat breeders were pooled and diluted in skimmed milk (SM) or Tris-egg yolk (TEY)-based extenders and supplemented with different concentrations of MO extract (0, 1, 2 and 5 mg/mL). After the freeze-thaw cycle, sperm kinetics and viability were assessed. RESULTS: With the SM extender, straightness, wobble and plasma membrane integrity were lower than in the control group (P < 0.05). With the TEY extender, wobble was lower in with 5 mg/mL MO extract than in the control group (P < 0.05). As regards sperm ultrastructure, evaluated by SEM, the MO extract, regardless of the diluent used, damaged the membrane of sperm cells in a dose-dependent manner. CONCLUSION: The addition of aqueous extract of MO leaves in both diluents at all concentrations tested affects the parameters of sperm progressivity and damages the plasma membrane in a dose-dependent manner. DOI: 10.54680/fr23310110712.


Asunto(s)
Moringa oleifera , Preservación de Semen , Masculino , Animales , Congelación , Cabras , Criopreservación/veterinaria , Motilidad Espermática , Preservación de Semen/veterinaria , Semillas , Espermatozoides , Yema de Huevo/química , Crioprotectores/farmacología
10.
Auton Neurosci ; 246: 103073, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36736078

RESUMEN

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.


Asunto(s)
Hipertermia Inducida , Canales Catiónicos TRPV , Animales , Masculino , Ratas , Capsaicina/farmacología , Ratas Sprague-Dawley , Ratas Wistar , Canales Catiónicos TRPV/fisiología
11.
Braz J Med Biol Res ; 55: e11976, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35857996

RESUMEN

Non-biodegradable metals such as mercury accumulate in living organisms during life (bioaccumulation) and also within trophic webs (biomagnification) and may reach high concentrations in humans. The contamination of humans by mercury in drinking water and food may be common, in particular in riverside communities that have a diet rich in fish. In vitro studies of human cell lines exposed to the cytotoxic and mutagenic effects of methylmercury have shown that prolactin has potential cytoprotective properties and may act as a co-mitogenic factor and inhibitor of apoptosis. The present in vivo study investigated the protective potential of prolactin against the toxic effects of methylmercury in the mammal Mus musculus. Histological and biochemical analyses, together with biomarker of genotoxicity, were used to verify the protective potential of prolactin in mice exposed to methylmercury. The reduction in kidney and liver tissue damage was not significant. However, results of biochemical and genotoxic analyses were excellent. After prolactin treatment, a significant reduction was observed in biochemical parameters and mutagenic effects of methylmercury. The study results therefore indicated that prolactin has protective effects against the toxicity of methylmercury and allowed us to suggest the continuation of research to propose prolactin in the future, as an alternative to prevent the damage caused by mercury, especially in populations that are more exposed.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Animales , Daño del ADN , Peces , Humanos , Mamíferos/metabolismo , Mercurio/análisis , Mercurio/metabolismo , Mercurio/toxicidad , Compuestos de Metilmercurio/toxicidad , Ratones , Prolactina/metabolismo
12.
Neurochirurgie ; 68(6): 583-588, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35700789

RESUMEN

BACKGROUND: Mesial temporal lobe epilepsy (MTLE) is a symptomatic epilepsy syndrome clinically characterized by high prevalence, pharmacoresistance, good surgical prognosis and hippocampal sclerosis (HS); however, no singular criteria can be considered sufficient for the MTLE-HS diagnosis. MicroRNAs (miRNAs) are small non-coding molecules that act as important gene-expression regulators at post-transcriptional level. Evidences on the involvement of miRNAs in epilepsy pathogenesis as well as their potential to be employed as biomarkers claim for investigations on miRNAs' applicability as epilepsy diagnosis and prognosis biomarkers. Consequently, the present study aimed to evaluate the applicability of three specific miRNAs as biomarkers of diagnosis and surgical outcomes in adult patients with MTLE-HS. METHOD: Hippocampus, amygdala and blood samples from 20 patients with MTLE-HS were analyzed, 10 with favorable surgical prognosis (Engel I) and 10 with unfavorable surgical prognosis (Engel III-IV). For the control groups, hippocampus and amygdala from necropsy and blood samples from healthy individuals were adopted. The miRNAs expression analysis was performed using Real-Time Quantitative Polymerase Chain Reaction for miRNAs highlighted from microarray as being involved in GABAergic neurotransmission. RESULTS: The miRNAs miR-629-3p, miR-1202 and miR-1225-5p were found to be hyper-expressed in MTLE-HS patients' blood. CONCLUSIONS: Our data suggest the existence of three circulating miRNAs (miR-629-3p, miR-1202 and miR-1225-5p) that could possibly act as additional tools in the set of factors that contribute to MTLE-HS diagnose.


Asunto(s)
Epilepsia del Lóbulo Temporal , MicroARNs , Adulto , Humanos , Epilepsia del Lóbulo Temporal/diagnóstico , Epilepsia del Lóbulo Temporal/genética , Epilepsia del Lóbulo Temporal/cirugía , Esclerosis/diagnóstico , Esclerosis/metabolismo , Esclerosis/patología , Hipocampo/cirugía , Hipocampo/metabolismo , Hipocampo/patología , MicroARNs/genética , MicroARNs/metabolismo , Biomarcadores
13.
Biochem Cell Biol ; 100(3): 246-265, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35443139

RESUMEN

Macrophages play critical roles in inflammation and defense against pathogens, as well as in the return to tissue homeostasis. Macrophage subpopulations displaying antagonistic phenotypes are generally classified as proinflammatory M1, implicated in antipathogen and antitumoral activities, or as anti-inflammatory M2, associated with tissue repair. Granulocytic and monocytic myeloid-derived suppressor cells recruited from the bone marrow to tissues and phagocytosis of apoptotic neutrophils can attenuate macrophage microbicidal activity. Here, we showed that bone marrow neutrophils, but not thioglycollate-recruited neutrophils, directly suppress the responses of macrophages that were previously committed to an inflammatory phenotype. Cocultures of inflammatory macrophages with bone marrow CD11b+Ly6Ghi granulocytes led to reduced release of IL-1ß, TNF-α, and IL-6 by macrophages after lipopolysaccharide stimulation. The suppressive activity was unrelated to granulocyte apoptosis or to secreted factors and required cell-to-cell contact. The suppressive effect was paralleled by reduction in the nuclear levels of the NF-κB p65 subunit, but not of the p50 subunit. Furthermore, bone marrow granulocytes decreased the phagocytic activity of macrophages and their capacity to kill intracellular Escherichia coli. Taken together, these results show that bone marrow granulocytes can function as suppressors of the proinflammatory activity and microbial-killing responses of macrophages.


Asunto(s)
Médula Ósea , Macrófagos , Granulocitos , Humanos , Inflamación , Fagocitosis
15.
Comput Biol Med ; 141: 105103, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34959112

RESUMEN

During recent years there has been a growing interest in stochastic dynamic neural fields employed for modeling and predictions in biomedical and technical systems. In this paper, given some incomplete noisy data available from sensors, we propose and explore a state estimation method for fast restorations of membrane potential in the cortex based on such measurements and the Amari equation used for simulations of neural population activity in a stochastic setting. Our novel technique relies upon a Galerkin-type spectral approximation utilized within the conventional state-space approach. Translating a stochastic system into its state-space form creates a straightforward and fruitful way to the data-driven parameter estimation, filtering, prediction and smoothing. The present study is particularly focused on establishing a nonlinear stochastic Galerkin-spectral-approximation-induced system of large size, which is further estimated by the traditional extended Kalman filter (EKF). The efficiency of calculations is the main purpose of our research. That is why the fast filtering solution devised is based on processing the incoming data incrementally, that is, by processing measurements one at a time, rather than handling them as a unified high-dimensional vector. Such sequential filters suit well for dealing with large data sets as well as with real-time on-line computations. Also, their derivation and substantiation is of great interest in the context of neural network training because of large stochastic systems arisen there. In comparison to the batch filtering, our novel algorithm reduces the computational cost of membrane potential reconstructions in terms of the amount of grid nodes N accepted in the underlying spacial discretization, significantly. Apart from its computation efficiency, this sequential method is more robust to round-off errors committed within a computer-based finite precision arithmetics than the classical EKF because of the (N × N)-matrix inversion elimination from such membrane potential calculations. The superior performance of our technique is examined and confirmed in comparison to the batch one on two known scenarios in the dynamic neural field modeling.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Corteza Cerebral
16.
Braz. j. med. biol. res ; 55: e11976, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1384153

RESUMEN

Non-biodegradable metals such as mercury accumulate in living organisms during life (bioaccumulation) and also within trophic webs (biomagnification) and may reach high concentrations in humans. The contamination of humans by mercury in drinking water and food may be common, in particular in riverside communities that have a diet rich in fish. In vitro studies of human cell lines exposed to the cytotoxic and mutagenic effects of methylmercury have shown that prolactin has potential cytoprotective properties and may act as a co-mitogenic factor and inhibitor of apoptosis. The present in vivo study investigated the protective potential of prolactin against the toxic effects of methylmercury in the mammal Mus musculus. Histological and biochemical analyses, together with biomarker of genotoxicity, were used to verify the protective potential of prolactin in mice exposed to methylmercury. The reduction in kidney and liver tissue damage was not significant. However, results of biochemical and genotoxic analyses were excellent. After prolactin treatment, a significant reduction was observed in biochemical parameters and mutagenic effects of methylmercury. The study results therefore indicated that prolactin has protective effects against the toxicity of methylmercury and allowed us to suggest the continuation of research to propose prolactin in the future, as an alternative to prevent the damage caused by mercury, especially in populations that are more exposed.

17.
Braz J Biol ; 84: e251883, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34852137

RESUMEN

The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.


Asunto(s)
Mariposas Nocturnas , Saccharum , Sorghum , Animales , Larva , Saccharum/genética , Sorghum/genética , Spodoptera
18.
Braz. j. biol ; 81(4): 928-933, Oct.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153425

RESUMEN

Abstract Species of Trichogramma Westwood, 1833 (Hymenoptera: Trichogrammtidae) are frequently used as biological control agents against Lepidoptera, but practical application of these egg endoparasitoids are complicated because of their complex taxonomy. This study aimed to compare sequences of internal transcribed spacer regions of ribosomal DNA (ITS2-rDNA) of Trichogramma accessions with those deposited in GenBank in order to access the reliability of the ITS2 as a barcode for discriminating species and evaluating the genetic diversity. ITS2-rDNA sequences obtained from seventeen specimens of Trichogramma confirmed previous identifications based on morphological characteristics. Multiple sequence alignment revealed the existence of highly conserved regions in ITS2 sequences while the neighbour-joining dendrogram indicated that the specimens formed three clusters comprising T. manicobai and T. marandobai (group I), T. galloi (group II) and T. pretiosum (group III). The ITS2 marker was shown to be a powerful DNA barcode for discriminating Trichogramma species and could be used to complement the morphological approach.


Resumo Espécies de Trichogramma Westwood, 1833 (Hymenoptera: Trichogrammatidae) são freqüentemente usadas como agentes de controle biológico contra Lepidoptera, esses endoparasitóides de ovos apresentam taxonomia complexa, o que dificulta sua aplicação prática. Este estudo teve como objetivo comparar seqüências de regiões espaçadoras internas transcritas de DNA ribossômico (ITS2-rDNA) de acessos de Trichogramma com aquelas depositadas no GenBank, a fim de avaliar a confiabilidade do ITS2 barcode para discriminar espécies e avaliar a diversidade genética. As seqüências de ITS2-rDNA obtidas de dezessete espécimes de Trichogramma confirmaram identidades anteriores com base em características morfológicas. O alinhamento de múltiplas sequências revelou a existência de regiões altamente conservadas nas sequências ITS2, enquanto o dendrograma indicou que os espécimes formavam três grupos compreendendo T. manicobai e T. marandobai (grupo I), T. galloi (grupo II) e T. pretiosum (grupo III). O marcador ITS2 mostrou ser um poderoso DNA barcode para discriminar espécies de Trichogramma podendo ser usado como complemento da abordagem morfológica.


Asunto(s)
Animales , Himenópteros/genética , Filogenia , Variación Genética/genética , ADN Ribosómico/genética , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN , ADN Espaciador Ribosómico/genética
19.
AJNR Am J Neuroradiol ; 42(12): 2119-2126, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34674995

RESUMEN

In the field of interventional neuroradiology, antiplatelet agents are commonly used to prepare patients before the implantation of permanent endovascular materials. Among the available drugs, clopidogrel is the most frequently used one, but resistance phenomena are considered to be relatively common. Prasugrel and ticagrelor were recently added to the pharmacologic arsenal, but the safety of these agents in patients undergoing neurointerventional procedures is still a subject of discussion. The cumulative experience with both drugs is less extensive than that with clopidogrel, and the experience with patients in the neurology field is less extensive than in the cardiology domain. In the present article, we provide a narrative review of studies that investigated safety issues of oral P2Y12 inhibitors in interventional neuroradiology and discuss potential routes for future research.


Asunto(s)
Inhibidores de Agregación Plaquetaria , Antagonistas del Receptor Purinérgico P2Y , Clopidogrel , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Clorhidrato de Prasugrel , Antagonistas del Receptor Purinérgico P2Y/efectos adversos , Ticagrelor , Resultado del Tratamiento
20.
J Eur Acad Dermatol Venereol ; 35(9): 1881-1887, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33988887

RESUMEN

BACKGROUND: Melasma can be refractory to treatment, and relapses are frequent. Thiamidol is a new potent tyrosinase inhibitor that has been found effective as a cosmeceutical for the depigmenting of melasma. OBJECTIVE: This study compared the efficacy and tolerability of topical 0.2% Thiamidol vs. 4% hydroquinone for facial melasma. METHODS: Fifty women with facial melasma participated in a randomized, evaluator-blinded, controlled study from September through November 2020. Patients were randomly assigned to apply a double layer of 0.2% Thiamidol twice a day or 4% hydroquinone cream at bedtime, for 90 days. Both groups received tinted sunscreen (sun protection factor 60, PPD 20). The primary outcome was the change from the baseline Modified Melasma Area Seve:rity Index (mMASI) score. Secondary outcomes were improvements in the patients' quality of life [Melasma Quality of Life Index (MELASQoL)], colourimetry, and Global Aesthetic Improvement Scale (GAIS) evaluation. RESULTS: One participant, from the hydroquinone group, did not complete the study (unrelated to adverse effects). The mean (SD) age of the participants was 43 (6) years, and 86% were phototypes III-IV. Both groups exhibited a reduction in mMASI, MELASQoL, and colour contrast scores (P < 0.01). The mean [95% confidence interval (CI 95%)] reductions of the mMASI scores were 43% (35-50%) for Thiamidol and 33% (23-42%) for hydroquinone. There was no difference between the groups in the reductions in mMASI, MELASQoL, colourimetric contrast and GAIS scores (P ≥ 0.09). The GAIS analysis resulted in an improvement of 84% (CI: 95% 67-97%) for participants in the Thiamidol group and 74% (CI: 95% 61-93%) for those in the hydroquinone group. There were only mild adverse effects in the Thiamidol group, but allergic contact dermatitis was evidenced in two (8%) participants. CONCLUSION: The melasma improvement achieved using 0.2% Thiamidol did not differ from that of 4% hydroquinone cream. Thiamidol can be considered a suitable option for melasma patients with poor tolerability or treatment failure with hydroquinone.


Asunto(s)
Hidroquinonas , Melanosis , Adulto , Femenino , Humanos , Hidroquinonas/efectos adversos , Melanosis/tratamiento farmacológico , Recurrencia Local de Neoplasia , Calidad de Vida , Resorcinoles/efectos adversos , Resultado del Tratamiento
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