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1.
Public Health ; 234: 58-63, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38954883

RESUMO

OBJECTIVES: In the American regions, Brazil accounts for 97% of visceral leishmaniasis (VL) cases, with a case fatality rate of approximately 10%. This study aimed to investigate the VL mortality distribution in Brazil and identify high-priority and high-risk areas for intervention strategies. STUDY DESIGN: This was an ecological study that analysed the spatial-temporal patterns of VL mortality in Brazilian municipalities. METHODS: Age-standardised VL mortality rates from the Global Burden of Disease study from 2001 to 2018 were used. The distribution of mortality in the municipalities was assessed, and subsequently the Local Index of Spatial Autocorrelation (LISA) analysis was conducted to identify contiguous areas with high mortality rates. Scan analysis identified clusters of high spatial-temporal risks. RESULTS: The highest mortality rates and clusters were in municipalities located in the Northeast region and in the states of Tocantins and Roraima (North region), Mato Grosso do Sul (Central-West region), and Minas Gerais (Southeast region). According to LISA, there was an increase in the number of municipalities classified as high priority from the first 3-year period (n = 434) to the last 3-year period (n = 644). The spatio-temporal analysis identified 21 high-risk clusters for VL mortality. CONCLUSION: Areas with a high risk of VL mortality should prioritise preventing transmission, invest in early diagnosis and treatment, and promote the training of healthcare professionals.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38717133

RESUMO

INTRODUCTION: Fragile X syndrome (FXS) is the most common cause of hereditary genetic disorder in a single gene characterised by intellectual disability. Behavioural features such as autism, hyperactivity and anxiety disorder may be present. Biofilm development and pathogenicity of Streptococcus mutans may be altered because FXS renders the dental approach and oral hygiene more complex. OBJECTIVES: The purpose of this study was to compare the levels of transcripts for VicRK and CovR of S. mutans isolated from FXS patients with the levels of transcripts for VicRK and CovR of standard strain ATCC, using a quantitative polymerase chain reaction (qPCR). METHODS: The caries experience index was assessed by the International Caries Detection and Assessment System (ICDAS), Periodontal Condition Index (PCI) and Invasive Dental Treatment Need Index (INI). RESULTS: The clinical index findings revealed a high rate of caries cavities and bleeding on probing of FXS patients. When VicRK and CovR transcript levels were compared with the reference strain, Fragile X patients were found to have significantly higher values. CONCLUSION: The present study demonstrated that FXS patients have more adverse clinical conditions, with increased biofilm accumulation and virulence. When combined with behavioural abnormalities, these patients become even more vulnerable to dental caries.

3.
Braz J Biol ; 84: e281361, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451631

RESUMO

The present study sought to evaluate the antimicrobial and anti-adherent potential of Eucalyptus radiata essential oil against food-borne strains of Escherichia coli. The study was performed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). In addition, the disk diffusion technique was used to evaluate the association of Eucalyptus radiata essential oil with synthetic antimicrobials. The Minimum Inhibitory Adherence Concentration (MIC) was also performed. The results revealed that E. radiata showed antimicrobial activity against the E. coli strains tested, with MIC values ranging from 500 µg/mL to 1000 µg/mL and MBC values ranging from 500 µg/mL to 1,024 µg/mL. As for the associations, it was observed that E. radiata oil exhibited a synergistic effect for some antibiotics, especially Ceftriaxone, with greater interference from the essential oil. Furthermore, it was effective in inhibiting the adherence of bacterial strains of E. coli, showing a more significant antibiofilm effect than the antibacterial agent 0.12% chlorhexidine digluconate. In summary, the essential oil of E. radiata showed antimicrobial potential against strains of E. coli of food origin, and can therefore, through in-depth studies, be used alone or in association with synthetic antimicrobials to combat infections caused by this pathogen.


Assuntos
Eucalyptus , Produtos da Carne , Óleos Voláteis , Escherichia coli , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia
4.
Braz J Biol ; 83: e276814, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970908

RESUMO

Integrated nutrient management is a promising way to avoid plant nutrient shortages because of the positive relationship between the bioavailability of nutrients and greater economic interest in their application through organic amendments and microbial application. To examine how compost, charcoal, and rhizobium influence maize development, an experiment was set up in a container. In addition to the appropriate amounts of nitrogen, phosphorous, and potassium, the soil in the allotted pots was treated with 50 ml of rhizobium, 5 tonnes of compost, and 2.5 tonnes of biochar before maize seeds were planted. A total of nine treatments (with three replicates each) were arranged in a completely randomized design for this experiment. Various agronomic, chemical, and physiological data were measured and recorded after the crop was harvested 110 days after sowing. The results showed that when biochar, compost, and rhizobium were applied together, the root fresh biomass rose by 43.4%, the root dry biomass increased by 38.3%, and the shoot length increased by 61.7%, compared to the control treatment. Chlorophyll content (41.3% higher), photosynthetic rate (58.5% higher), transpiration rate (64.4% higher), quantum yield (32.6% higher), and stomatal conductivity (25.3% higher) were all significantly improved compared to the control. Soil levels of nitrogen, phosphorus, and potassium were also improved with this treatment compared to the control. The combined use of biochar, compost, and rhizobium was more successful than any of the components used individually in boosting maize yields. Based on the findings of our study, the integration of rhizobium, biochar, and compost within a unified treatment shown a substantial enhancement in both the growth and yield of maize.


Assuntos
Solo , Zea mays , Solo/química , Fertilizantes , Fósforo , Plantas , Potássio , Nitrogênio/análise
5.
Braz J Biol ; 83: e273843, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466515

RESUMO

Instead of typical household trash, the heavy metal complexes, organic chemicals, and other poisons produced by huge enterprises threaten water systems across the world. In order to protect our drinking water from pollution, we must keep a close eye on the situation. Nanotechnology, specifically two-dimensional (2D) nanomaterials, is used in certain wastewater treatment systems. Graphene, g-C3N4, MoS2, and MXene are just a few examples of emerging 2D nanomaterials that exhibit an extraordinary ratio of surface (m3), providing material consumption, time consumption, and treatment technique for cleaning and observing water. In this post, we'll talk about the ways in which 2D nanomaterials may be tuned to perform certain functions, namely how they can be used for water management. The following is a quick overview of nanostructured materials and its possible use in water management: Also discussed in length are the applications of 2D nanomaterials in water purification, including pollutant adsorption, filtration, disinfection, and photocatalysis. Fluorescence sensors, colorimetric, electrochemical, and field-effect transistors are only some of the devices being studied for their potential use in monitoring water quality using 2D nanomaterials. Utilizing 2D content has its benefits and pitfalls when used to water management. New developments in this fast-expanding business will boost water treatment quality and accessibility in response to rising awareness of the need of clean, fresh water among future generations.


Assuntos
Nanoestruturas , Purificação da Água , Nanoestruturas/química , Nanotecnologia/métodos , Purificação da Água/métodos , Qualidade da Água
6.
Braz J Biol ; 83: e271809, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37222373

RESUMO

The 2030 Sustainable Development Goals of the United Nations include a strong emphasis on ending hunger worldwide. According to the 2019 Global Food Security Index, while 88% of countries claim there is sufficient food supply in their country, the sad reality is that 1 in 3 countries is facing insufficient availability of food supply, which means that in those countries, more than 10% of the population is malnourished. Since nutrition is crucial to leading a healthy life and satisfying food security needs, several governments have turned to national nutrition surveys to gauge the extent of malnutrition in their populations. Plants are able to grow, develop, and store nutrients by photosynthesis, which convert light into chemical energy through cell redox regulatory networks. A photosynthesis system's electron flow may be adjusted to accommodate varying light and environmental circumstances. Many techniques exist for controlling the flow of electrons emitted during light processes in order to save or waste energy. The two protein molecules TROL and flavoenzyme ferredoxin (oxidoreductase+NADP) (FNR) interact dynamically to form an excellent molecular switch capable of splitting electrons from the photosystem. The TROL-FNR bifurcation may be limited by either generating NADPH or preventing reactive oxygen species from propagating. TROL-based genome editing is an experimental method for enhancing plant stress and defensive responses, efficiency, and ultimately agricultural production.


Assuntos
Agricultura , NADP
7.
Braz J Biol ; 84: e256691, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544787

RESUMO

microRNAs (miRNAs) are recognized as diabetes mellitus type 2 (T2DM) biomarkers useful for disease metabolism comprehension and have great potential as therapeutics targets. BDNF and IGF1 increased expression are highly involved in the benefits of insulin and glucose paths, however, they are down-regulated in insulin resistance conditions, while their expression increase is correlated to the improvement of glucose and insulin metabolism. Studies suggest the microRNA regulation of these genes in several different contexts, providing a novel investigation approach for comprehending T2DM metabolism and revealing potential therapeutic targets. In the present study, we investigate in different animal models (human, rat, and mouse) miRNAs that target BDNF and IGF1 in skeletal muscle tissue with T2DM physiological conditions. Bioinformatics tools and databases were used to miRNA prediction, molecular homology, experimental validation of interactions, expression in the studied physiological condition, and network interaction. The findings showed three miRNAs candidates for IGF1(miR-29a, miR-29b, and miR-29c) and one for BDNF (miR-206). The experimental evaluations and the search for the expression in skeletal muscle from T2DM subjects confirmed the predicted interaction between miRNA-mRNA for miR-29b and miR-206 through human, rat, and mouse models. This interaction was reaffirmed in multiple network analyses. In conclusion, our results show the regulation relationship between miR-29b and miR-206 with the investigated genes, in several tissues, suggesting an inhibition pattern. Nevertheless, these data show a large number of possible interaction physiological processes, for future biotechnological prospects.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Insulinas , MicroRNAs , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Biologia Computacional , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucose/uso terapêutico , Humanos , Resistência à Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/uso terapêutico , Insulinas/uso terapêutico , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/uso terapêutico , Ratos
8.
Theriogenology ; 178: 60-66, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34775200

RESUMO

5 fluorouracil (5FU), an antineoplastic drug, is often utilized in the therapeutic regimen for several types of cancer, including the hepatoblastoma in children. The effects of 5FU on the population of ovarian preantral follicles, which is the largest oocyte reservoir, is still poorly understood. The integrity of the ovarian preantral follicle pool is important for lifelong fertility. The better understanding of such effects may favor intervention strategies to protect fertility in 5FU-treated children and women coping with cancer. To analyze the effects of 5FU on isolated murine secondary follicles in vitro, ovaries were collected from young mice (28-30 days old), and secondary follicles were isolated and cultured for 12 days in basic culture medium, with or without 5FU at concentrations of 0.3 mM, 1 mM, 3 mM, 10 mM, and 30 mM. In the in vitro study, we analyzed the percentage of morphologically normal follicles, antrum formation, follicular diameter, and hormone production. On day 12, oocytes were recovered for in vitro maturation. 5FU treatment did not alter the percentage of morphologically normal follicles. On day 12, only 1, 10, and 30 mM 5FU significantly reduced the percentage of antrum. From day 4 onwards, 5FU treatments significantly reduced follicle diameter. The meiosis resumption rate was significantly lower in all 5FU treatments. 5FU concentrations ≥3 mM reduced estradiol levels. In conclusion, 5FU does not affect follicular morphology. However, 5FU deleteriously affects follicular growth, estradiol production, and oocyte maturation in isolated ovarian follicles.


Assuntos
Antineoplásicos , Fluoruracila , Animais , Feminino , Fluoruracila/farmacologia , Meiose , Camundongos , Oócitos , Folículo Ovariano
9.
Int J Pharm ; 603: 120658, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33964336

RESUMO

Vulvovaginal candidiasis (VVC) is an extremely common type of vaginal infection, which is mainly caused by Candida albicans. However, non-albicans Candida species are frequently more resistant to conventional antifungal agents and can represent up to 30% of cases. Due to side effects and increasing antifungal resistance presented by standard therapies, phenolic compounds, such as p-coumaric acid (p-CA), have been studied as molecules from natural sources with potential antifungal activity. p-CA is a poorly water-soluble compound, thus loading it into liquid crystals (LCs) may increase its solubility and effectiveness on the vaginal mucosa. Thereby, here we propose the development of mucoadhesive liquid crystalline systems with controlled release of p-CA, for the local treatment of VVC. Developed LCs consisted of fixed oily and aqueous phases (oleic acid and cholesterol (5:1) and poloxamer dispersion 16%, respectively), changing only the surfactant phase components (triethanolamine oleate (TEA-Oleate) or triethanolamine (TEA), the latter producing TEA-Oleate molecules when mixed with oleic acid). Systems were also diluted in artificial vaginal mucus (1:1 ratio) to mimic the vaginal environment and verify possible structural changes on formulations upon exposure to the mucosa. From the characterization assays, p-CA loaded TEA-Oleate systems presented mucoadhesive profile, liquid crystalline mesophases, well-organized structures and pseudoplastic behaviour, which are desirable parameters for topical formulations. Moreover, they were able to control the release of p-CA throughout the 12 h assay, as well as decrease its permeation into the vaginal mucosa. p-CA showed antifungal activity in vitro against reference strains of C. albicans (SC5314), C. glabrata (ATCC 2001) and C. krusei (ATCC 6258), and exhibited higher eradication of mature biofilms than amphotericin B and fluconazole. In vivo experiments demonstrated that the formulations reduced the presence of filamentous forms in the vaginal lavages and provided an improvement in swelling and redness present in the mice vaginal regions. Altogether, here we demonstrated the potential and feasibility of using p-CA loaded liquid crystalline systems as a mucoadhesive drug delivery system for topical treatment of VVC.


Assuntos
Candidíase Vulvovaginal , Cristais Líquidos , Animais , Antifúngicos/uso terapêutico , Candida albicans , Candidíase Vulvovaginal/tratamento farmacológico , Ácidos Cumáricos , Feminino , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Propionatos
10.
Animal ; 14(11): 2271-2276, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32580812

RESUMO

The farrowing process is one of the most energy-demanding activities for the modern hyperprolific sow. This study evaluated the effects of supply of energy on the expected date of farrowing on the farrowing kinetics and piglets' performance during the first 24 h after birth. A total of 80 sows were used. The sows and their respective litters were considered as the experimental unit. On the expected day of farrowing, the sows were allocated to one of the following groups: sows that did not have access to feed from farrowing induction until the end of the farrowing process (CON, n = 40); sows fed 500 g of energetic supplement, which consisted of 250 g of the basal lactation diet plus 250 g of cane sugar, 18 h after farrowing induction (SUP, n = 40). The farrowing duration, farrowing assistance, birth interval, number of total born, stillborn and mummified piglets were recorded for each sow. Piglets were weighed individually at birth and 24 h later. The interval from birth to first suckle was evaluated individually for each piglet in 16 randomly selected litters (eight litters per treatment group). Blood glucose concentrations of six sows were measured shortly after expulsion of the first piglet. Farrowing duration, farrowing assistance and stillborn rate tended to be greater (P = 0.06, P = 0.09 and P = 0.07, respectively) in sows from the CON group compared to sows from the SUP group. However, there was no difference (P > 0.05) between the groups for birth interval. Colostrum intake was greater (P < 0.05) for piglets from the SUP group compared to piglets from the CON group. Additionally, BW gain of the piglets suckling the SUP group was greater (P < 0.05) than those suckling the CON group at 24 h after birth. The blood glucose concentrations during the expulsive stage of farrowing were greater (P < 0.05) in the SUP group than for sows from the CON group. In conclusion, supplying modern hyperprolific sows energy on the expected day of farrowing is a valuable nutritional intervention to improve the farrowing kinetics and piglets' performance in early life.


Assuntos
Peso ao Nascer , Parto , Suínos/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Colostro , Feminino , Cinética , Lactação , Gravidez
11.
Braz. j. biol ; 80(2): 273-284, Apr.-June 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132386

RESUMO

Abstract The production of litterfall is essential for nutrient cycling in terrestrial ecosystems. From November 2009 to October 2011, analyzed the monthly litterfall production in two areas of Caatinga, a type of Seasonally Dry Tropical Forest located in the Cariri Paraibano, in the semiarid region of the Paraíba, Northeastern Brazil. One of the areas, Private Natural Heritage Reserve (RPPN) Fazenda Almas, is legally protected, and the other, Fazenda Moreiras, does not. The aims were to evaluate the effects of precipitation, evapotranspiration and vegetation structure on the temporal and spatial dynamics of litterfall production. Eight sampling points were randomly chosen at each site, and two 1 m2 collectors were installed 50 m apart from each other. The collected material was sorted, dried and weighed. Additionally, the characteristics (density, species richness, height and mean basal area) of the tree-shrub stratum in plots with a 10 m radius surrounding each collector. Total litterfall production was 4,500 kg ha-1 yr-1 for Fazenda Almas and 3,300 kg ha-1 yr-1 for Fazenda Moreiras; these values were within the expected range for Seasonally Dry Tropical Forests. The inter- and intra-annual variation in litterfall production was positively correlated with precipitation and evapotranspiration rates, and four months after the highest precipitation rates, there was a marked decrease in litterfall occurred during the dry season. Furthermore, the contributions of the material fractions were distinct with the leaf fraction representing for more than 60% of the litterfall, and the vegetation structure explained 75% of the variation in litterfall production. Therefore, climatic factors and vegetation structure affect the temporal and spatial dynamics of litterfall production and consequently influence nutrient dynamics in the semiarid region of Brazil.


Resumo A produção de serapilheira é essencial para a ciclagem de nutrientes em ecossistemas terrestres. De Novembro de 2009 a Outubro de 2011, foi analisada a produção de serapilheira em duas áreas de Caatinga, um tipo de Floresta Tropical sazonalmente Seca localizada no Cariri Paraibano, na região do semiárido da Paraíba, Nordeste do Brasil. Uma das áreas, Reserva Particular do Patrimônio Natural - RPPN - Fazenda Almas, é legalmente protegida, ao contrário da outra, Fazenda Moreiras. Os objetivos foram avaliar o efeito da precipitação, evapotranspiração e estrutura da vegetação sobre a dinâmica temporal e espacial da produção de serapilheira. Oito pontos de amostragem foram escolhidos aleatoriamente em cada localidade, e dois coletores de 1 m2 foram instalados a 50 m um do outro. O material coletado foi triado, secado e pesado. Adicionalmente, foram registradas as características (densidade, riqueza de espécies, altura e área basal média) das espécies arbóreo-arbustivas na parcela com um raio (r) de 10 m ao redor de cada coletor. A produção total de serapilheira foi 4,500 Kg ha-1 yr-1 para a Fazenda Almas e 3,300 kg ha-1 yr-1 para a Fazenda Moreiras; estes valores estão dentro da faixa esperada para as Florestas Tropicais sazonalmente secas. A variação inter e intranual na produção de serapilheira foi positivamente correlacionada com as taxas de precipitação e evapotranspiração, e quatro meses depois das maiores taxas de precipitação, houve uma diminuição acentuada na serapilheira coletada durante a estação seca. Além disso, as contribuições das frações de material foram distintas com a fração de folha representando mais que 60% da serapilheira, e a estrutura da vegetação explicou 75% da variação na produção de serapilheira. Portanto, os fatores climáticos e a estrutura da vegetação afetam a dinâmica temporal e espacial da produção de serapilheira e, consequentemente, influenciam a dinâmica de nutrientes na região semiárida do Brasil.


Assuntos
Florestas , Ecossistema , Estações do Ano , Árvores , Clima Tropical , Brasil
12.
Neotrop Entomol ; 49(3): 445-455, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32020496

RESUMO

Pest populations are mostly regulated by climate, intra- and interspecific competition, natural enemies, and host plant quality. Myzus persicae (Sulzer) (Hemiptera: Aphididae) is a widely adapted aphid in the agroecosystems and is one of the main bell pepper pests. In the present study, we determined the spatial and temporal dynamics and the regulatory factors of M. persicae populations in bell pepper crops. The number of aphids and their natural enemies were evaluated during 2 years in four commercial bell pepper fields. Myzus persicae density data were related to temperature, rainfall, and natural enemies by multiple regression analysis and were then submitted to geostatistical analysis. The density of M. persicae was higher during the plant's reproductive growth stage. Rainfall, Chrysoperla spp., and Toxomerus spp. regulate M. persicae populations. Initial infestations of this pest occur along the edges of the fields and subsequently spread towards the center. This information is useful for integrated management programs aimed at anticipating periods of higher abundance of M. persicae and identifying arthropods to be prioritized in biological control.


Assuntos
Afídeos/fisiologia , Capsicum , Animais , Brasil , Produtos Agrícolas , Dinâmica Populacional , Estações do Ano , Análise Espaço-Temporal , Tempo (Meteorologia)
13.
Theriogenology ; 144: 67-73, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31918071

RESUMO

The aim of this study was to evaluate follicular survival and development of ovine isolated secondary follicles cultured in medium containing fixed or sequential concentrations of melatonin and further oocyte maturation. Isolated secondary follicles were cultured for 18 days in α-MEM+ alone (control) or with different concentrations of melatonin (100, 500 or 1000 pg/mL) or sequential concentrations of melatonin (Mel Seq: Day 6 = 100; Day 12 = 500; Day 18 = 1000 pg/mL). The percentages of morphologically normal follicles and antral cavity formation increased significantly in 1000 pg/mL melatonin compared to the other treatments. After 18 days, 1000 pg/mL melatonin (Mel 100) showed a greater (P < 0.05) follicular diameter than α-MEM+, 100 and 500 pg/mL melatonin. In addition, the concentration of 500 pg/mL melatonin showed a higher (P < 0.05) percentage of fully grown oocytes than α-MEM+, Mel 100 and Mel Seq treatments. After oocyte maturation, the levels of ROS were lower (P < 0.05) in 1000 pg/mL melatonin (Mel 1000) than in other treatments. Both Mel 1000 and Mel Seq treatments showed significantly higher levels of mitochondrial activity than other treatments. There were no significant differences between 500 and 1000 pg/mL melatonin regarding meiotic stages. In conclusion, the concentration of 1000 pg/mL melatonin maintains survival, promotes follicular development and increases the levels of active mitochondria after in vitro culture of sheep secondary follicles. Moreover, this concentration promotes the meiotic competence of oocytes and decreases the production of ROS during oocyte maturation.


Assuntos
Meiose/fisiologia , Melatonina/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Feminino , Glutationa , Técnicas de Maturação in Vitro de Oócitos/veterinária , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio
14.
Braz J Biol ; 80(2): 273-284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31389481

RESUMO

The production of litterfall is essential for nutrient cycling in terrestrial ecosystems. From November 2009 to October 2011, analyzed the monthly litterfall production in two areas of Caatinga, a type of Seasonally Dry Tropical Forest located in the Cariri Paraibano, in the semiarid region of the Paraíba, Northeastern Brazil. One of the areas, Private Natural Heritage Reserve (RPPN) Fazenda Almas, is legally protected, and the other, Fazenda Moreiras, does not. The aims were to evaluate the effects of precipitation, evapotranspiration and vegetation structure on the temporal and spatial dynamics of litterfall production. Eight sampling points were randomly chosen at each site, and two 1 m2 collectors were installed 50 m apart from each other. The collected material was sorted, dried and weighed. Additionally, the characteristics (density, species richness, height and mean basal area) of the tree-shrub stratum in plots with a 10 m radius surrounding each collector. Total litterfall production was 4,500 kg ha-1 yr-1 for Fazenda Almas and 3,300 kg ha-1 yr-1 for Fazenda Moreiras; these values were within the expected range for Seasonally Dry Tropical Forests. The inter- and intra-annual variation in litterfall production was positively correlated with precipitation and evapotranspiration rates, and four months after the highest precipitation rates, there was a marked decrease in litterfall occurred during the dry season. Furthermore, the contributions of the material fractions were distinct with the leaf fraction representing for more than 60% of the litterfall, and the vegetation structure explained 75% of the variation in litterfall production. Therefore, climatic factors and vegetation structure affect the temporal and spatial dynamics of litterfall production and consequently influence nutrient dynamics in the semiarid region of Brazil.


Assuntos
Ecossistema , Florestas , Brasil , Estações do Ano , Árvores , Clima Tropical
15.
Domest Anim Endocrinol ; 71: 106386, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31809950

RESUMO

This study aimed to evaluate the effect of melatonin on the in vitro culture and maturation of isolated sheep early antral follicles. Isolated early antral follicles were cultured for 12 d in α-minimum essential medium (MEM+) alone (control) or α-MEM+ added with fixed different concentrations (100, 500, or 1,000 pg/mL) or a sequential concentration of melatonin (MelSeq; day 6 = 100; day 12 = 500 pg/mL). The percentage of morphologically normal follicles was higher (P < 0.05) in 500 pg/mL melatonin than the other treatments at 6 d. Mel 500 also showed a higher rate of fully grown oocytes (P < 0.05) than other treatments. After in vitro culture, reactive oxygen species (ROS) levels in oocytes were similar between Mel 500 and MelSeq, with both being lower (P < 0.05) than other treatments. Oocytes cultured in both Mel 500 and Mel 1000 showed glutathione peroxidase levels similar (P > 0.05) to the control group and higher (P < 0.05) than other treatments. Mitochondrial activity was similar (P > 0.05) among control, Mel 500, and Mel 1000 treatments. Mel 500 treatment presented a higher percentage of germinal vesicle breakdown oocytes than the control group and similar percentages to the other treatments. Follicles cultured in melatonin followed by oocyte maturation with the addition of 500 pg/mL melatonin in maturation medium showed increased (P < 0.05) levels of mitochondrial activity compared to α-MEM+ alone. In conclusion, the concentration of 500 pg/mL of melatonin promotes development and decreases ROS levels of ovine oocytes from in vitro grown early antral follicles. Moreover, melatonin increases mitochondrial activity and promotes the acquisition of meiotic competence of these oocytes.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/veterinária , Melatonina/farmacologia , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Feminino , Glutationa/metabolismo , Mitocôndrias/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Cultura de Tecidos/veterinária
16.
Domest Anim Endocrinol ; 67: 71-79, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30765293

RESUMO

This study evaluated the in vitro development and maturation of ovine oocytes from secondary follicles cultured in serum-free medium containing fixed or sequential concentrations of recombinant human FSH (rhFSH). Follicles were cultured in α-MEM+ alone or with constant (500, 750, or 1,000 ng/mL) or sequential concentrations of rhFSH (seq. 1: day 6 = 500; day 12 = 750; day 18 = 1,000 ng/mL and seq. 2: day 6 = 100; day 12 = 500; day 18 = 1,000 ng/mL). At the end of the experiment, follicular survival was higher (P < 0.05) in 750 ng/mL rhFSH than the control and 1,000 ng/mL rhFSH. As early as day 6 of culture, antral cavity formation was observed in all treatments. Follicular diameter increased progressively and significantly in all treatments throughout 18 d of culture. Furthermore, addition of rhFSH to the medium promoted a significant increase in the percentage of fully grown oocytes in all treatments compared to α-MEM+. Mitochondrial activity was higher in rhFSH treatments than in the control, except in rhFSH seq. 2 (P < 0.05). Maturation rates increased in oocytes from intact follicles cultured in 750 ng/mL rhFSH compared to the control (P < 0.05). In conclusion, rhFSH at 750 ng/mL maintained the survival of secondary follicles cultured in serum-free medium, improved oocyte growth, mitochondrial activity, and oocyte maturation.


Assuntos
Meios de Cultura Livres de Soro , Hormônio Foliculoestimulante Humano/administração & dosagem , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Ovinos , Animais , Fragmentação do DNA , Feminino , Humanos , Técnicas de Maturação in Vitro de Oócitos/métodos , Mitocôndrias/fisiologia , Oócitos/efeitos dos fármacos , Oócitos/ultraestrutura , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Proteínas Recombinantes/administração & dosagem
17.
Int J Dent Hyg ; 16(4): 441-449, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29473687

RESUMO

OBJECTIVE: To summarize evidence regarding the effectiveness of using chlorhexidine for oral healthcare on patients in the intensive care unit for the prevention of nosocomial pneumonia and ventilator-associated pneumonia. METHODS: This overview of systematic reviews was developed using articles found in PUBMED, Cochrane Library, LILACS, CRD, CINHAL, manual search and grey literature. RESULTS: Of the total 16 systematic reviews, 14 included meta-analysis. Most of them were classified with high methodological quality. In seven systematic reviews, chlorhexidine was effective for prevention of nosocomial pneumonia and ventilator-associated pneumonia in adult population in cardiothoracic intensive care unit. The effectiveness was contradictory with other population patients in intensive care units. CONCLUSION: Chlorhexidine has proven to be effective for the prevention of NP among adult populations in cardiothoracic ICU. In ICUs with patients who have varied clinical-surgical conditions, the effectiveness of chlorhexidine for the prevention of PN and VAP was inconclusive.


Assuntos
Serviço Hospitalar de Cardiologia , Clorexidina/administração & dosagem , Pneumonia Associada a Assistência à Saúde/prevenção & controle , Unidades de Terapia Intensiva , Antissépticos Bucais/administração & dosagem , Pneumonia/etiologia , Pneumonia/prevenção & controle , Ventiladores Mecânicos/efeitos adversos , Humanos , Metanálise como Assunto , Revisões Sistemáticas como Assunto
18.
Theriogenology ; 110: 44-51, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29331831

RESUMO

This study evaluated the effect of bone morphogenetic proteins 2 (BMP2) and 4 (BMP2) on follicle development and mRNA expression for GDF9, Cyclin B1, BMPR1A, BMPR1B, BMPRII, FSHR and SMAD1 in bovine secondary follicles cultured in vitro. Isolated secondary follicles were cultured for 18 days in TCM199+ medium alone or supplemented with BMP2 (10 ng/mL), BMP4 (100 ng/mL) or combination of both BMP2 and 4. Real-time PCR was used to analyze mRNA levels in fresh and cultured follicles. After 18 days of culture, follicles cultured with BMP2 alone or with BMP4 alone had larger diameters when compared to control (P < .05). In addition, all treatments promoted antrum formation and maintained a high viability rate through the growing period. The presence of BMP2, BMP4 or both together did not influence mRNA expression for the tested genes. However, the in vitro culture induces down-regulation for mRNA expression of BMPR1A. In conclusion, the addition of BMP2 or BMP4 alone in cultured medium promotes follicular growth and antrum formation in bovine follicles after 18 days of in vitro culture.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 4/farmacologia , Folículo Ovariano/efeitos dos fármacos , Animais , Receptores de Proteínas Morfogenéticas Ósseas/genética , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , Oogênese/genética , Folículo Ovariano/fisiologia
19.
Phys Chem Chem Phys ; 19(47): 31756-31765, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29167854

RESUMO

Pr(OH)3 one-dimensional nanostructures are a less studied member of lanthanide hydroxide nanostructures, which recently demonstrated an excellent adsorption capacity for organic pollutant removal from wastewater. In this study, Pr1-xEux(OH)3 (x = 0, 0.01, 0.03, and 0.05) defective nanostructures were synthesized by a facile and scalable microwave-assisted hydrothermal method using KOH as an alkaline metal precursor. The phase and surface composition, morphology, vibrational, electronic and optical properties of the as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectrometry (ICP-OES), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Raman, infrared (IR), photoluminescence (PL), and diffuse reflectance spectroscopy (DRS). It was deduced that the incorporation of Eu3+ ions promoted the formation of oxygen vacancies in the already defective Pr(OH)3, subsequently changing the Pr(OH)3 nanorod morphology. The presence of KNO3 phase was registered in the Eu-doped samples. The oxygen-deficient Eu-doped Pr(OH)3 nanostructures displayed an improved photocatalytic activity in the removal of reactive orange (RO16) dye under UV-vis light irradiation. An enhanced photocatalytic activity of the Eu-doped Pr(OH)3 nanostructures was caused by the synergetic effect of oxygen vacancies and Eu3+ (NO3-) ions present on the Pr(OH)3 surface, the charge separation efficiency and the formation of the reactive radicals. In addition, the 3% Eu-doped sample exhibited very good adsorptive properties due to different morphology and higher electrostatic attraction with the anionic dye. Pr1-xEux(OH)3 nanostructures with the possibility of tuning their adsorption/photocatalytic properties present a great potential for wastewater treatment.

20.
Zygote ; 25(4): 391-403, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28766468

RESUMO

Constant progress in the diagnosis and treatment of cancer disease has increased the number and prognosis of cancer survivors. However, the toxic effects of chemotherapy and radiotherapy on ovarian function have resulted in premature ovarian failure. Patients are, therefore, still expecting methods to be developed to preserve their fertility successfully. Several potential options are available to preserve fertility in patients who face premature ovarian failure, including immature or mature oocyte and embryo cryopreservation. However, for children or prepubertal women needing immediate chemotherapy, cryopreservation of ovarian tissue is the only alternative. The ultimate aim of this strategy is to implant ovarian tissue into the pelvic cavity (orthotopic site) or in a heterotopic site once oncological treatment is completed and the patient is disease free. Transplantation of ovarian tissue with sufficiently large numbers of follicles could potentially restore endocrine function and allow multiple cycles for conception. However, the success of ovarian tissue transplantation still has multiple challenges, such as the low number of follicles in the graft that may affect their longevity as well as the survival of the tissue during ex vivo processing and subsequent transplantation. Therefore, this review aims to summarize the achievements of ovary grafting and the potential techniques that have been developed to improve ovarian graft survival.


Assuntos
Transplante de Órgãos/métodos , Ovário/fisiologia , Ovário/transplante , Animais , Criopreservação/métodos , Feminino , Preservação da Fertilidade/métodos , Humanos , Ovário/irrigação sanguínea , Ovário/citologia , Transplante Heterólogo/métodos
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