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1.
Braz J Biol ; 84: e286941, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39230086

RESUMEN

Seed priming with biostimulant for soybean is a promising practice contributing positively to the physiological quality and vigor of seedlings, but there are little studies regarding protocols of bioinputs, such as Ascophyllum nodosum L. seaweed extract. We aimed to evaluate the effect of doses of A. nodosum macroalgae in seed priming and its impact on germination and seedling vigor of soybean. Seeds were subjected to priming with A. nodosum extract (ANE) at doses of 0, 1, 2, 3, 4, and 5 mL kg seed-1 during 15 min. Priming with ANE did not influence the first count and seed germination. Soybean seedlings from priming with 5 mL kg-1 ANE showed higher growth and shoot and root dry biomass. We observed increase 18% for shoot dry matter with priming of 5 mL kg-1 ANE compared to untreated seeds. The responses were variable for the emergence speed index in function ANE and did not influence the photochemical processes in photosystem II. Seed priming with ANE contributed in higher chlorophyll index. ANE showed a biostimulant effect on soybean seedlings, providing better growth and biomass characteristics, being promising in seed priming, but further studies are suggested in order to increase information regarding its use protocol for soybean.


Asunto(s)
Ascophyllum , Germinación , Glycine max , Plantones , Semillas , Ascophyllum/química , Glycine max/crecimiento & desarrollo , Glycine max/efectos de los fármacos , Germinación/fisiología , Germinación/efectos de los fármacos , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Plantones/crecimiento & desarrollo , Biomasa , Algas Marinas/fisiología , Extractos Vegetales/farmacología , Clorofila/análisis
2.
Eur Biophys J ; 52(8): 661-671, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37542583

RESUMEN

The kinetics of an ion channel are classically understood as a random process. However, studies have shown that in complex ion channels, formed by multiple subunits, this process can be deterministic, presenting long-term memory. Staphylococcus aureus α-hemolysin (α-HL) is a toxin that acts as the major factor in Staphylococcus aureus virulence. α-HL is a water-soluble protein capable of forming ion channels into lipid bilayers, by insertion of an amphipathic  ß-barrel. Here, the α-HL was used as an experimental model to study memory in ion channel kinetics. We applied the approximate entropy (ApEn) approach to analyze randomness and the Detrended Fluctuation Analysis (DFA) to investigate the existence of long memory in α-HL channel kinetics. Single-channel currents were measured through experiments with α-HL channels incorporated in planar lipid bilayers. All experiments were carried out under the following conditions: 1 M NaCl solution, pH 4.5; transmembrane potential of + 40 mV and temperature 25 ± 1 °C. Single-channel currents were recorded in real-time in the memory of a microcomputer coupled to an A/D converter and a patch-clamp amplifier. The conductance value of the α-HL channels was 0.82 ± 0.0025 nS (n = 128). The DFA analysis showed that the kinetics of α-HL channels presents long-term memory ([Formula: see text] = 0.63 ± 0.04). The ApEn outcomes showed low complexity to dwell times when open (ApEno = 0.5514 ± 0.28) and closed (ApEnc = 0.1145 ± 0.08), corroborating the results of the DFA method.


Asunto(s)
Proteínas Hemolisinas , Canales Iónicos , Membrana Dobles de Lípidos , Proteínas Hemolisinas/metabolismo , Canales Iónicos/metabolismo , Cinética , Staphylococcus aureus
3.
Public Health ; 221: 66-72, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37421755

RESUMEN

OBJECTIVE: To describe trends in the prevalence of diabetes mellitus (DM) in Brazil and to analyze its association with the consumption of artificially sweetened beverages among individuals aged 18 years or older. STUDY DESIGN: This was a repeated cross-sectional study. METHODS: Annual data from VIGITEL surveys (2006-2020) were used, which included adults from all Brazilian state capitals. The outcome was the prevalence of DM (type 1 and type 2). The main exposure variable was consuming beverages like soft drinks and artificial juices, either in its 'diet, light, or zero' form. Covariates included sex, age, sociodemographic characteristics, smoking, alcohol consumption, physical activity, fruit consumption, and obesity. The temporal trend in the indicators and the etiological fraction (population attributable risk [PAR]) were calculated. Analyses were performed using Poisson regression. The association between DM and consumption of beverages was tested, excluding the year 2020 due to the pandemic; restricting the analysis to the final three years (2018-2020). RESULTS: Overall, 757,386 subjects were included. The prevalence of DM increased from 5.5% to 8.2%, with an annual growth of 0.17 percentage points (95% CI 0.11-0.24). Among those who consumed diet/light/zero beverages, the annual percentage change of DM was four times greater. The PAR corresponding to the consumption of diet/light/zero beverages on the occurrence of DM was 17%. CONCLUSIONS: An increasing prevalence of DM was observed, while diet/light/zero beverages consumption remains stable. A substantial reduction in the annual percentage change of DM could be observed if people stopped consuming diet/light soda/juice.


Asunto(s)
Diabetes Mellitus , Edulcorantes , Adulto , Humanos , Brasil/epidemiología , Bebidas Endulzadas Artificialmente , Estudios Transversales , Bebidas/efectos adversos , Diabetes Mellitus/epidemiología , Diabetes Mellitus/etiología
4.
Cuad. psicol. deporte ; 22(3): 41-47, sep.-dic. 2022. graf, tab
Artículo en Inglés | IBECS | ID: ibc-209141

RESUMEN

The study evaluates the perception of body image associated with food consumption, sedentary behavior, and practice of physical activity responses during the COVID-19 lockdown in the academic population ofa Brazilian University. Four hundred fifteenstudentsanswered an online survey during 1-31 May/2020. Frequencieswere used to describe the outcomes, and the Chi-square test (p< 0.05)to determine associations. A negativeperception of change in body image was found in both females and males (e.g., 73% and 55%, respectively), significantly associated with a perception of an increase in food consumption, watching TV and social media (more than 2 hours), not practicing physical activity in females, and with an increase in food consumption in males. The results presented a generalpicture of behavioral responses during the COVID-19 pandemicofstudents in Brazil, suggesting that a negative perception of body image changinghas been associated with health-related behaviors, especially in females. (AU)


El estudio evalúa la percepción de la imagen corporal asociada al consumo de alimentos, el comportamiento sedentario y las respuestas a la práctica de actividad física durante el confinamientodelaCOVID-19 en la población académica de una universidad brasileña. Cuatrocientos y quince estudiantes respondieron un survey 1 al 31 de mayo de 2020. Se utilizaron frecuencias para describir los resultados y la prueba de Chi-Squared(p< 0,05) para las asociaciones. Se encontró una percepción negativa del cambio en la imagen corporal tanto en mujeres como en hombres (73% y 55%), significativamente asociada con una percepción de aumento en el consumo de alimentos, ver televisión y redes sociales (más de 2 horas),no practicar actividad física en mujeres y con el consumo de alimentos en hombres. Los resultados presentaron un panorama general de las respuestas de comportamiento durante laCOVID-19 en estudiantes de Brasil, lo que sugiere que una percepción negativa del cambio de la imagen corporal se ha asociado con comportamientos relacionados con la salud, especialmente en las mujeres. (AU)


O presente estudo avaliou a percepção da imagem corporal com consumo de alimentos, comportamento sedentário e a prática de atividade física durante o lockdodown em uma população acadêmica de uma universidade brasileira. Quatrocentos e quinze estudantes responderam um questionário on-line durante 1-31 de maio de 2020. Frequências foram utilizadas para descrever os resultados e o teste Qui-Quadrado (p<0,05) para determinar a associação. Foi encontrada uma mudança negativa na percepção da imagem corporal em ambos homens e mulheres (73% e 55%), sendo significativamente associadas com o aumento perceptual do consumo alimentar, assistir TV e uso de mídia social(mais de 2 horas), não praticar atividade física pelas mulheres, e consumo alimentar para homens. Os resultados apresentam uma resposta geral do comportamento de estudantes brasileiros durante o surto do COVID-19, sugerindo que uma percepção negativa de mudança na imagem corporal seja associada com comportamentos relacionados a saúde, especialmente em mulheres. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Pandemias , Infecciones por Coronavirus/epidemiología , Imagen Corporal , Actividad Motora , 24457 , Conducta Sedentaria , Estudios Transversales , Epidemiología Descriptiva , Encuestas y Cuestionarios , Brasil
5.
Plant Biol (Stuttg) ; 24(2): 292-301, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34806266

RESUMEN

'Brejos de altitude' is an ecosystem that has been subjected to severe exploitation, leading to an intense reduction in Brazil. Understanding the patterns of bryophyte diversity and composition, particularly of specialized species such as the epiphylls, to anthropic and abiotic variables is crucial for implementing protection measures. We investigated the relationship between composition and diversity of epiphyllous bryophytes and anthropic (edge effects) and abiotic (altitude) variables at local (within each 'Brejo') and regional (set of three 'Brejos') scale. Abiotic and anthropic variables were correlated with alpha and beta diversity (decomposed into species replacement and richness differences) using GLM. Their effects on species composition were evaluated using PERMANOVA. The localities at higher elevations harboured a richer bryoflora and overall beta diversity patterns were associated with altitude and locality, which acted over different scales. Regionally, the contribution of richness differences was limited with increasing altitude. Yet, dissimilarities among localities were associated with richness differences and replacement, denoting the importance of local factors. The composition was explained by local factors interacting with the regional altitudinal gradient. Anthropic activity was significant only when interacting with local factors and altitudinal gradient. Environmental filtering associated with altitude played a more important role in shaping the diversity and composition of epiphyllous bryophytes, at both regional and local scales. Each 'Brejo' acts as an ecological refuge, harbouring part of the whole environmental gradient, and presents a unique floristic composition. Moreover, partitioning beta diversity highlighted the interplay of local and regional forces shaping diversity patterns.


Asunto(s)
Briófitas , Ecosistema , Altitud , Biodiversidad , Brasil
6.
Acta Biotheor ; 69(4): 697-722, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34043104

RESUMEN

Ion channels are transport proteins present in the lipid bilayers of biological membranes. They are involved in many physiological processes, such as the generation of nerve impulses, hormonal secretion, and heartbeat. Conformational changes in the ion channel-forming protein allow the opening or closing of pores to control the ionic flux through the cell membranes. The opening and closing of the ion channel have been classically treated as a random kinetic process, known as a Markov process. Here the time the channel remains in a given state is assumed to be independent of the condition it had in the previous state. More recently, however, several studies have shown that this process is not random but a deterministic one, where both the open and closed dwell-times and the ionic current flowing through the channel are history-dependent. This property is called long memory or long-range correlation. However, there is still much controversy regarding how this memory originates, which region of the channel is responsible for this property, and which models could best reproduce the memory effect. In this article, we provide a review of what is, where it is, its possible origin, and the mathematical methods used to analyze the long-term memory present in the kinetic process of ion channels.


Asunto(s)
Canales Iónicos , Modelos Biológicos , Canales Iónicos/metabolismo , Cinética , Cadenas de Markov
7.
Braz J Med Biol Res ; 52(2): e7559, 2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30698224

RESUMEN

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.


Asunto(s)
Percepción de Color , Visión de Colores , Pruebas de Visión/métodos , Adulto , Femenino , Humanos , Embarazo , Complicaciones del Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;52(2): e7559, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-984027

RESUMEN

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.


Asunto(s)
Humanos , Femenino , Embarazo , Adulto , Pruebas de Visión/métodos , Percepción de Color , Visión de Colores , Complicaciones del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Primer Trimestre del Embarazo
9.
J Hum Nutr Diet ; 31(2): 266-275, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28791776

RESUMEN

BACKGROUND: Predictive equations are the main clinical tools for determining resting energy expenditure (REE). However, their adequate use in overweight and obese individuals is unclear. Thus, we investigated the best predictive equations for estimating REE in overweight and obese women with polycystic ovary syndrome (PCOS). METHODS: Eleven analyses were performed with prediction equations (pREE) based on anthropometric parameters in 30 overweight or obese women with PCOS without other chronic diseases. The measured REE (mREE) was calculated by indirect calorimetry. The validity of the equations was investigated by comparison, accuracy and agreement tests between pREE and mREE at both the individual and group level. RESULTS: Four analyses were similar to those of mREE, and smallest mean differences were observed for the World Health Organization/Food and Agriculture Organization of the United Nations/United Nations University (WHO/FAO/UNU) considering weight (W) [0.07 (1.13) MJ (16 [270] kcal)]. Individual accuracy was greater than 50% for Harris and Benedict, Müller and Lazzer equations. The percentage of REE underestimation ranged between 16.7% and 73.3%, whereas higher rates of overestimation were observed in the De Luis (66.7%) and Ireton-Jones (43.3%) equations. Mean bias at the group level was lowest in the WHO/FAO/UNU W and WHO/FAO/UNU considering weight and height (WH), Müller and Lazzer equations (-2.8 to 0.5). The WHO/FAO/UNU W and WHO/FAO/UNU WH formulas were optimal in individual agreement (33.3%). CONCLUSIONS: FAO/WHO/UNU W equations may estimate the REE in overweight and obese women with PCOS. However, the low individual accuracy and agreement in relation to mREE suggest caution regarding when to use the formula to perform an individual nutritional plan.


Asunto(s)
Metabolismo Basal , Índice de Masa Corporal , Conceptos Matemáticos , Modelos Biológicos , Obesidad/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Descanso , Adolescente , Adulto , Antropometría , Calorimetría Indirecta , Femenino , Humanos , Persona de Mediana Edad , Modelos Teóricos , Obesidad/complicaciones , Sobrepeso , Síndrome del Ovario Poliquístico/complicaciones , Reproducibilidad de los Resultados , Adulto Joven
10.
Plant Dis ; 101(6): 957-963, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30682922

RESUMEN

The roots of maize seedlings typically are attacked by a complex of organisms that includes fungal pathogens and plant-parasitic nematodes but few studies have examined the effects of these organisms in combination. Rhizoctonia solani can be an important component of the seedling disease complex; like other fungi, its effect on the plant may be influenced by the activity of nematodes such as the root-lesion nematode Pratylenchus penetrans. In this study, we assessed the impact of seed treatments, including fungicide-nematicide combinations, on maize seedlings exposed to R. solani and P. penetrans alone or in combination. In growth-chamber and greenhouse experiments, seed treated with various active ingredient combinations were planted in an autoclaved sand-soil mixture with or without inoculum of R. solani. In some treatments, a suspension of P. penetrans adults and juveniles was added to the sand-soil mixture. In the greenhouse experiments, infection by R. solani caused dramatic reductions in root length, volume, surface area, and numbers of root tips and root forks, whereas P. penetrans infestation alone reduced only shoot fresh weight. Statistical interactions between the effects of the two organisms were not significant, although fungal infestation significantly reduced the numbers of nematodes extracted from roots. Seed treatments significantly improved most root development variables, and the combination that included four fungicides, thiamethoxam, and abamectin was the best treatment for most variables. Results were similar in the growth-chamber experiments, where R. solani caused significant reductions in nearly all shoot and root development measurements, and seed treatment with sedaxane, alone or combined with abamectin, consistently provided the best results. R. solani was more damaging to seedlings than P. penetrans, and the combination of the two organisms did not cause more damage than R. solani alone. Seed-treatment active ingredients that specifically targeted R. solani (sedaxane) and P. penetrans (abamectin) had large positive effects on seedling health, causing significant improvements in root and shoot growth and development compared with untreated seedlings exposed to these pathogens.

11.
Interação psicol ; 20(2): 226-233, maio-ago. 2016.
Artículo en Portugués | Index Psicología - Revistas | ID: psi-69574

RESUMEN

Essa revisão tem por objetivo apresentar os resultados dos estudos que avaliaram prevalência e/ou níveisde depressão e ansiedade nas mulheres com endometriose. Para isso, uma pesquisa bibliográfica foirealizada no PubMed, LILACS e Web of Science e foram selecionados para leitura 21 artigos. Destes,onze analisaram depressão e ansiedade simultaneamente, nove apenas depressão e um ansiedade. Foiobservado que as pacientes com endometriose exibem níveis elevados de depressão e ansiedade,provavelmente devido aos quadros frequentes de dor, a infertilidade, ao atraso no diagnóstico e arecorrência da doença. Conclui-se que um acompanhamento psicológico deve ser oferecido a mulherescom endometriose sendo, portanto um componente essencial para o tratamento dessa condiçãoginecológica(AU)


Asunto(s)
Depresión/psicología , Endometriosis/psicología , Ansiedad/psicología
12.
Plant Dis ; 100(2): 431-437, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30694121

RESUMEN

Seedling diseases of maize are caused by a complex of organisms, including fungi in the genus Fusarium. Root-lesion nematodes (Pratylenchus spp.) are common in fields where maize is grown, and they are known to interact with Fusarium spp. in several crops. The objectives of this study were to assess the impacts of seed treatment combinations on maize seedlings coinfected with Pratylenchus penetrans and two Fusarium spp. that cause seedling disease symptoms (Fusarium graminearum and F. verticillioides) and to determine whether there were interactions between P. penetrans and the Fusarium spp. Growth-chamber experiments were conducted with fungicide- or nematicide-treated or untreated maize seed planted in a sand-soil mixture infested with inoculum of either F. graminearum or F. verticillioides. A suspension of 4,000 P. penetrans (mixed stages) was added to the pots at the time of planting. After 30 days, shoot length and fresh and dry shoot and root weights were determined. Total root length and fine root length, root volume, numbers of root tips and forks, and root surface area were measured through analysis of digital images of the root systems. After 42 days, P. penetrans nematodes were extracted and quantified from roots and soil. There were significant effects of the treatments on root health with interactions between Fusarium spp. and P. penetrans. F. graminearum caused the greatest reductions in root and shoot growth, and interactions with P. penetrans were more evident for F. verticillioides than for F. graminearum. Image analysis of root system architecture showed that seed treatment significantly improved root system characteristics. Seed treatments containing the nematicide abamectin in combination with fungicides reduced root infection by P. penetrans and provided the healthiest root system when under attack by the Fusarium-Pratylenchus complex.

13.
Chem Biol Interact ; 244: 129-139, 2016.
Artículo en Inglés | LILACS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1022413

RESUMEN

The use of natural products has a long tradition in medicine, and they have proven to be an important source of lead compounds in the development of new drugs. Among the natural compounds, terpenoids present broad-spectrum activity against infective agents such as viruses, bacteria, fungi, protozoan and helminth parasites. In this study, we report a biological screening of 38 chemically characterized terpenes from different classes, which have a hydroxyl group connected by hydrophobic chain or an acceptor site, against the blood fluke Schistosoma mansoni, the parasite responsible for schistosomiasis mansoni. In vitro bioassays revealed that 3,7-dimethyl-1-octanol (dihydrocitronellol) (10) was the most active terpene (IC50 values of 13­52 µM) and, thus, we investigated its antischistosomal activity in greater detail. Confocal laser scanning microscopy revealed that compound 10 induced severe tegumental damage in adult schistosomes and a correlation between viability and tegumental changes was observed. Furthermore, we compared all the inactive compounds with dihydrocitronellol structurally by using shape and charge modeling. Lipophilicity (miLogP) and other molecular properties (e.g. molecular polar surface area, molecular electrostatic potential) were also calculated. From the 38 terpenes studied, compound 10 is the one with the greatest flexibility, with a sufficient apolar region by which it may interact in a hydrophobic active site. In conclusion, the integration of biological and chemical analysis indicates the potential of the terpene dihydrocitronellol as an antiparasitic agent.


Asunto(s)
Parásitos , Parasitología , Bacterias , Preparaciones Farmacéuticas , Hongos
14.
Mol Cell Endocrinol ; 400: 102-11, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25451978

RESUMEN

The phenotypic differentiation between oxytocin (OT)- and vasopressin (VP)-secreting magnocellular neurosecretory cells (MNCs) from the supraoptic nucleus is relevant to understanding how several physiological and pharmacological challenges affect their electrical activity. Although the firing patterns of OT and VP neurons, both in vivo and in vitro, may appear different from each other, much is assumed about their characteristics. These assumptions make it practically impossible to obtain a confident phenotypic differentiation based exclusively on the firing patterns. The presence of a sustained outward rectifying potassium current (SOR) and/or an inward rectifying hyperpolarization-activated current (IR), which are presumably present in OT neurons and absent in VP neurons, has been used to distinguish between the two types of MNCs in the past. In this study, we aimed to analyze the accuracy of the phenotypic discrimination of MNCs based on the presence of rectifying currents using comparisons with the molecular phenotype of the cells, as determined by single-cell RT-qPCR and immunohistochemistry. Our results demonstrated that the phenotypes classified according to the electrophysiological protocol in brain slices do not match their molecular counterparts because vasopressinergic and intermediate neurons also exhibit both outward and inward rectifying currents. In addition, we also show that MNCs can change the relative proportion of each cell phenotype when the system is challenged by chronic hypertonicity (70% water restriction for 7 days). We conclude that for in vitro preparations, the combination of mRNA detection and immunohistochemistry seems to be preferable when trying to characterize a single MNC phenotype.


Asunto(s)
Potenciales de Acción/fisiología , Neuronas/metabolismo , Oxitocina/metabolismo , ARN Mensajero/metabolismo , Núcleo Supraóptico/metabolismo , Vasopresinas/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Dieta , Expresión Génica , Masculino , Microtomía , Neuronas/clasificación , Neuronas/citología , Neuronas/efectos de los fármacos , Oxitocina/genética , Técnicas de Placa-Clamp , Fenotipo , ARN Mensajero/genética , Ratas , Ratas Wistar , Análisis de la Célula Individual , Sodio en la Dieta/farmacología , Núcleo Supraóptico/citología , Núcleo Supraóptico/efectos de los fármacos , Técnicas de Cultivo de Tejidos , Vasopresinas/genética , Privación de Agua
15.
Rev. bras. plantas med ; Rev. bras. plantas med;17(4,supl.3): 1187-1191, 2015. tab, graf
Artículo en Portugués | LILACS | ID: lil-776599

RESUMEN

RESUMO O fator mais importante na manutenção da saúde periodontal é o adequado controle do biofilme dentário. Face às dificuldades no controle mecânico por parte dos pacientes, métodos alternativos ou complementares têm sido utilizados como coadjuvantes químicos do controle do biofilme, auxiliando no tratamento da gengivite. Dentre esses métodos alternativos, destaca-se a fitoterapia, através da utilização de plantas medicinais. Dessa forma, esse estudo faz uma revisão sistemática tendo como objetivo a busca, na literatura atual, de estudos que comprovem a eficácia de produtos fitoterápicos à base de aroeira no controle do biofilme dental auxiliando no tratamento da gengivite. Foi realizada busca computadorizada nos indexadores MedLine, Lilacs, BBO e Scielo no período de Setembro a Outubro de 2014. Os descritores de pesquisa utilizados foram “biofilme”, “gengivite”, “aroeira”, “plantas medicinais” e “fitoterápicos”, bem como seus correspondentes em língua inglesa. Através dos descritores utilizados, foram encontrados 54 artigos. Após a aplicação dos critérios de inclusão e exclusão, chegou-se a 08 artigos: 05 revisões, 01 estudo clínico randomizado, 01 estudo experimental e 01 estudo observacional descritivo. De acordo com os estudos analisados, a aroeira apresentou atividades antifúngica e antimicrobiana eficazes, bem como potencial efeito de redução do índice de sangramento gengival, o que justifica seu uso no tratamento da gengivite.


ABSTRACT The most important factor to keep periodontal health is proper control of biofilm. Given the difficulties in the mechanical control by patients, alternative or complementary methods have been used as chemical supporting of biofilm control, helping the treatment of gingivitis. Among these alternatives, there is the phytotherapy, through the use of medicinal plants. Thus, this study it is a systematic review and aims to seek, in the current literature, researches proving the effectiveness of aroeira herbal products in the control of dental biofilm, assisting in the treatment of gingivitis. A computerized search was conducted in Medline, Lilacs, Scielo and BBO, from September to October of 2014. The search words used were “biofilm”, “gingivitis”, “aroeira”, “herbal medicines” and “phytotherapics” in Portuguese and English language. Through this method, 54 articles were found. After applying the inclusion and exclusion criteria, the research reached 08 items: 05 reviews, 01 randomized clinical trial, 01 experimental study and 01 descriptive observational study. According to the analyzed papers, the aroeira demonstrated effective antifungal and antimicrobial activities, as well as a potential reduction impact on gingival bleeding index, which would justify its use in the treatment of gingivitis.


Asunto(s)
Anacardiaceae/clasificación , Gingivitis/fisiopatología , Fitoterapia/instrumentación , Plantas Medicinales/clasificación , Placa Dental/clasificación
16.
Eur J Clin Microbiol Infect Dis ; 33(12): 2095-104, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24947175

RESUMEN

Bovine mastitis is the primary disease of dairy cattle that has a great impact on the dairy industry. It is estimated that worldwide economic losses due to mastitis range between US$82 and US$131 per cow/year. A fast and efficient diagnosis of the disease remains a major bottleneck that directly influences the speed with which treatment decisions and management are undertaken. Microbiological culture remains the gold standard in the identification of bacteria that cause mastitis, but the method has inherent limitations, such as a delay in obtaining results and cost, and requires special care during the collection and processing of the sample. For this reason, multiple groups have devoted efforts to develop alternative methods that, preferably, can be easily accomplished in the field. The specificity of the antigen-antibody reaction has enabled the emergence of major diagnostic methods used in clinical practice, such as immunoassays, which have significant advantages in terms of speed, sensitivity, specificity, and portability. Commercially, immunodiagnostics have been used in the detection of various diseases in cattle. However, in several cases, only a presumptive diagnosis can be made, which requires confirmation using culture-based methods. This review discusses the immunological-based assays developed since the 1990s for the detection of Staphylococcus aureus, which is considered the primary pathogen of contagious bovine mastitis. Although no ideal antigens ensure the accurate performance of tests and the costs need to be reduced to allow for good market competitiveness, immunoassays, particularly lateral flow immunoassay and immunoagglutination, have emerged as promising tests to be used in the field.


Asunto(s)
Pruebas Inmunológicas/métodos , Mastitis Bovina/diagnóstico , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/aislamiento & purificación , Animales , Bovinos , Femenino , Mastitis Bovina/inmunología , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología
17.
Sci Total Environ ; 488-489: 197-207, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24830932

RESUMEN

Tropospheric ozone is a secondary pollutant having a negative impact on health and environment. To control and minimize such impact the European Community established regulations to promote a clean air all over Europe. However, when an episode is related with natural mechanisms as Stratosphere-Troposphere Exchanges (STE), the benefits of an action plan to minimize precursor emissions are inefficient. Therefore, this work aims to develop a tool to identify the sources of ozone episodes in order to minimize misclassification and thus avoid the implementation of inappropriate air quality plans. For this purpose, an artificial neural network model - the Multilayer Perceptron - is used as a binary classifier of the source of an ozone episode. Long data series, between 2001 and 2010, considering the ozone precursors, (7)Be activity and meteorological conditions were used. With this model, 2-7% of a mean error was achieved, which is considered as a good generalization. Accuracy measures for imbalanced data are also discussed. The MCC values show a good performance of the model (0.65-0.92). Precision and F1-measure indicate that the model specifies a little better the rare class. Thus, the results demonstrate that such a tool can be used to help authorities in the management of ozone, namely when its thresholds are exceeded due natural causes, as the above mentioned STE. Therefore, the resources used to implement an action plan to minimize ozone precursors could be better managed avoiding the implementation of inappropriate measures.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Redes Neurales de la Computación , Ozono/análisis , Atmósfera/química , Europa (Continente)
18.
Braz J Med Biol Res ; 47(2): 90-100, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24519124

RESUMEN

Physiological evidence indicates that the supraoptic nucleus (SON) is an important region for integrating information related to homeostasis of body fluids. Located bilaterally to the optic chiasm, this nucleus is composed of magnocellular neurosecretory cells (MNCs) responsible for the synthesis and release of vasopressin and oxytocin to the neurohypophysis. At the cellular level, the control of vasopressin and oxytocin release is directly linked to the firing frequency of MNCs. In general, we can say that the excitability of these cells can be controlled via two distinct mechanisms: 1) the intrinsic membrane properties of the MNCs themselves and 2) synaptic input from circumventricular organs that contain osmosensitive neurons. It has also been demonstrated that MNCs are sensitive to osmotic stimuli in the physiological range. Therefore, the study of their intrinsic membrane properties became imperative to explain the osmosensitivity of MNCs. In addition to this, the discovery that several neurotransmitters and neuropeptides can modulate their electrical activity greatly increased our knowledge about the role played by the MNCs in fluid homeostasis. In particular, nitric oxide (NO) may be an important player in fluid balance homeostasis, because it has been demonstrated that the enzyme responsible for its production has an increased activity following a hypertonic stimulation of the system. At the cellular level, NO has been shown to change the electrical excitability of MNCs. Therefore, in this review, we focus on some important points concerning nitrergic modulation of the neuroendocrine system, particularly the effects of NO on the SON.


Asunto(s)
Neuronas/fisiología , Sistemas Neurosecretores/fisiología , Óxido Nítrico/fisiología , Oxitocina/metabolismo , Núcleo Supraóptico/fisiología , Vasopresinas/metabolismo , Potenciales de Acción/fisiología , Animales , Guanilato Ciclasa/metabolismo , Humanos , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Ratas , Equilibrio Hidroelectrolítico/fisiología
19.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;47(2): 90-100, 2/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-699775

RESUMEN

Physiological evidence indicates that the supraoptic nucleus (SON) is an important region for integrating information related to homeostasis of body fluids. Located bilaterally to the optic chiasm, this nucleus is composed of magnocellular neurosecretory cells (MNCs) responsible for the synthesis and release of vasopressin and oxytocin to the neurohypophysis. At the cellular level, the control of vasopressin and oxytocin release is directly linked to the firing frequency of MNCs. In general, we can say that the excitability of these cells can be controlled via two distinct mechanisms: 1) the intrinsic membrane properties of the MNCs themselves and 2) synaptic input from circumventricular organs that contain osmosensitive neurons. It has also been demonstrated that MNCs are sensitive to osmotic stimuli in the physiological range. Therefore, the study of their intrinsic membrane properties became imperative to explain the osmosensitivity of MNCs. In addition to this, the discovery that several neurotransmitters and neuropeptides can modulate their electrical activity greatly increased our knowledge about the role played by the MNCs in fluid homeostasis. In particular, nitric oxide (NO) may be an important player in fluid balance homeostasis, because it has been demonstrated that the enzyme responsible for its production has an increased activity following a hypertonic stimulation of the system. At the cellular level, NO has been shown to change the electrical excitability of MNCs. Therefore, in this review, we focus on some important points concerning nitrergic modulation of the neuroendocrine system, particularly the effects of NO on the SON.


Asunto(s)
Animales , Humanos , Ratas , Neuronas/fisiología , Sistemas Neurosecretores/fisiología , Óxido Nítrico/fisiología , Oxitocina , Núcleo Supraóptico/fisiología , Vasopresinas , Potenciales de Acción/fisiología , Guanilato Ciclasa/metabolismo , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Equilibrio Hidroelectrolítico/fisiología
20.
J Dairy Sci ; 97(3): 1812-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24440248

RESUMEN

This study aimed to investigate the in silico biofilm production ability of Staphylococcus aureus strains isolated from milking parlor environments on dairy farms from São Paulo, Brazil. The Staph. aureus isolates were obtained from 849 samples collected on dairy farms, as follows: milk from individual cows with subclinical mastitis or history of the disease (n=220); milk from bulk tank (n=120); surfaces of milking machines and utensils (n=389); and milk handlers (n=120). Thirty-one Staph. aureus isolates were obtained and categorized as pulsotypes by pulsed-field gel electrophoresis and submitted to assays for biofilm formation on polystyrene, stainless steel, rubber, and silicone surfaces. Fourteen (45.2%) pulsotypes were considered producers of biofilm on the polystyrene microplate assay, whereas 13 (41.9%) and 12 (38.7%) pulsotypes were biofilm producers on stainless steel and rubber, respectively. None of the pulsotypes evaluated produced biofilms on silicone. Approximately 45% of Staph. aureus pulsotypes isolated from different sources on dairy farms showed the ability to produce biofilms in at least one assay, indicating possible persistence of this pathogen in the milking environment. The potential involvement of Staph. aureus in subclinical mastitis cases and its occurrence in milk for human consumption emphasize the need to improve hygiene practices to prevent biofilm formation on the farms studied.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Leche/microbiología , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/fisiología , Animales , Brasil , Bovinos , Industria Lechera/instrumentación , Electroforesis en Gel de Campo Pulsado/veterinaria , Femenino , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Humanos , Mastitis , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/veterinaria
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