Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Braz. j. biol ; 84: e261001, 2024. tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1384066

RESUMO

Drought variability analysis is of utmost concern for planning and efficiently managing water resources and food security in any specific area. In the current study, drought spell occurrence has been investigated in the Balochistan province of Pakistan during the past four decades (1981-2020) using standardized precipitation index (SPI), reconnaissance drought index (RDI), and precipitation deciles (PD) at an annual timescale. Precipitation and temperature data collected from 13 synoptic meteorological stations located in Balochistan were used to calculate the SPI, the RDI, and the PD for calculation of drought severity and duration. Based on these indices, temporal analysis shows adverse impacts of drought spells in Nokkundi during 1991-1993, in Barkhan, Dalbandin, Quetta stations during 1999-2000, whereas Barkhan, Dalbandin, Lasbella, Sibi during 2002-2003, Zhob during 2010-2011, Kalat and Khuzdar during 2014-2015, and Panjgur during 2017-2018. Also, the aridity index for each station was calculated based on the UNEP method shows that major part of Balochistan lies in the arid zone, followed by the hyper-arid in the southwestern part and the semi-arid zones in the northeastern part of the province. SPI and RDI results were found more localized than PD, as PD shows extensive events. Furthermore, principal component analysis shows a significant contribution from all the indices. For SPI, RDI, and PD, the first three principal components have more than 70% share, contributing 73.63%, 74.15%, and 72.30% respectively. By integrating drought patterns, long-term planning, and preparedness to mitigate drought impacts are only possible. The RDI was found more suitable and recommended in case of temperature data availability.


A análise da variabilidade da seca é de extrema importância para o planejamento e gestão eficiente dos recursos hídricos e da segurança alimentar em qualquer área específica. No estudo atual, a ocorrência de períodos de seca foi investigada na província do Baluchistão, no Paquistão, durante as últimas quatro décadas (1981-2020), usando índice de precipitação padronizado (SPI), índice de seca de reconhecimento (RDI) e decis de precipitação (PD) em uma escala anual. Dados de precipitação e temperatura coletados de 13 estações meteorológicas sinóticas localizadas no Baluchistão foram usados ​​para calcular o SPI, o RDI e o PD para cálculo da severidade e duração da seca. A análise temporal mostra os impactos adversos dos períodos de seca em Nokkundi durante 1991-1993 e na maior parte da província de 1999 a 2004. Além disso, o índice de aridez para cada estação foi calculado com base no método do PNUMA. Os resultados de SPI e RDI foram encontrados mais localizados do que PD, pois PD apresenta eventos extensos. Além disso, a análise de componentes principais mostra uma contribuição significativa de todos os índices. Para SPI, RDI e PD, os três primeiros componentes principais têm mais de 70% de participação, contribuindo com 73,63%, 74,15% e 72,30%, respectivamente. O planejamento e a preparação de longo prazo para mitigar os impactos da seca só são possíveis por meio da integração dos padrões de seca.


Assuntos
Chuva , Recursos Hídricos , Estações Meteorológicas , Secas , Abastecimento de Alimentos , Paquistão
2.
Bol. latinoam. Caribe plantas med. aromát ; 22(2): 268-276, mar. 2023. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1555682

RESUMO

Grewia tenax (Forssk.) Fiori (Malvaceae) grows in the Arabian Peninsula and is used for several medicinal purposes. To characterize the dermatological bioactivities of G. tenax in terms of its antimelanoma, antityrosinase and antioxidant activities. Cytotoxicity was assessed by cell proliferation and mitochondrial viability assays. Ability to inhibit mushroom tyrosinase and scavenge free radicals were evaluated by an enzymatic and DPPH scavenging microtiter assay, respectively. Phytochemical analyses were carried out using TLC, HPLC-UV and NMR. The chloroform extract shown significant cytotoxic activity in terms of mitochondrial viability (43 ± 14 µg/mL). We identified lupeol and b-sitosterol as the main active components for the tyrosinase inhibitory activity of the hexane extract. Scavenging activity of the DPPH· radical was confined to the water extract. Extracts from this plant have the potential to be used as a base in the development of cosmeceutical products intended to whiten skin or to combat radical-induced physiopathological processes.


Grewia tenax (Forssk.) Fiori (Malvaceae) crece en la Península Arábiga y se utiliza con varios fines medicinales. Para caracterizar las bioactividades dermatológicas de G. tenax en cuanto a sus actividades antimelanoma, antitirosinasa y antioxidante; la citotoxicidad se evaluó mediante ensayos de proliferación celular y viabilidad mitocondrial. La capacidad para inhibir la tirosinasa de hongo y eliminar los radicales libres se evaluó mediante un ensayo de microtitulación enzimático y de eliminación de DPPH, respectivamente. Los análisis fitoquímicos se realizaron mediante TLC, HPLC-UV y NMR. El extracto de cloroformo mostró una actividad citotóxica significativa en términos de viabilidad mitocondrial (43 ± 14 µg/mL). Identificamos lupeol y b-sitosterol como los principales componentes activos para la actividad inhibitoria de tirosinasa del extracto de hexano. La actividad depuradora del radical DPPH· se limitó al extracto acuoso. Los extractos de esta planta tienen potencial para ser utilizados como base en el desarrollo de productos cosmecéuticos destinados a blanquear la piel o combatir procesos fisiopatológicos inducidos por radicales.


Assuntos
Citotoxinas/química , Grewia/química , Arábia Saudita , Técnicas In Vitro , Monofenol Mono-Oxigenase/farmacologia , Melanoma/terapia , Antioxidantes/farmacologia
3.
Braz J Biol ; 84: e261001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35674598

RESUMO

Drought variability analysis is of utmost concern for planning and efficiently managing water resources and food security in any specific area. In the current study, drought spell occurrence has been investigated in the Balochistan province of Pakistan during the past four decades (1981-2020) using standardized precipitation index (SPI), reconnaissance drought index (RDI), and precipitation deciles (PD) at an annual timescale. Precipitation and temperature data collected from 13 synoptic meteorological stations located in Balochistan were used to calculate the SPI, the RDI, and the PD for calculation of drought severity and duration. Based on these indices, temporal analysis shows adverse impacts of drought spells in Nokkundi during 1991-1993, in Barkhan, Dalbandin, Quetta stations during 1999-2000, whereas Barkhan, Dalbandin, Lasbella, Sibi during 2002-2003, Zhob during 2010-2011, Kalat and Khuzdar during 2014-2015, and Panjgur during 2017-2018. Also, the aridity index for each station was calculated based on the UNEP method shows that major part of Balochistan lies in the arid zone, followed by the hyper-arid in the southwestern part and the semi-arid zones in the northeastern part of the province. SPI and RDI results were found more localized than PD, as PD shows extensive events. Furthermore, principal component analysis shows a significant contribution from all the indices. For SPI, RDI, and PD, the first three principal components have more than 70% share, contributing 73.63%, 74.15%, and 72.30% respectively. By integrating drought patterns, long-term planning, and preparedness to mitigate drought impacts are only possible. The RDI was found more suitable and recommended in case of temperature data availability.


Assuntos
Secas , Meteorologia , Paquistão , Temperatura , Recursos Hídricos
4.
Metab Brain Dis ; 35(8): 1341-1351, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32827287

RESUMO

Serotonin exerts a significant role in the mammalian central nervous system embryogenesis and brain ontogeny. Therefore, we investigate the effect of perinatal fluoxetine (FLX), a selective serotonin reuptake inhibitor, administration on the behavioral expression of adult male Swiss mice. For this purpose, two groups (n = 6 each, and ~ 35 g) of pregnant female Swiss mice were mated. Their offspring were treated with FLX (10 mg/Kg, s.c.) from postnatal day (PND) 5 to 15. At PND 16, one male puppy of each litter was euthanized, and the hippocampus was dissected for RNA analysis. At 70 days of life, the male offspring underwent a behavioral assessment in the open field, object recognition task, light-dark box, tail suspension and rotarod test. According to our results, the programmed animals had a decrease in TPH2, 5HT1a, SERT, BDNF, and LMX1B expression. Also, it was observed less time of immobility in tail suspension test and higher grooming time in the open field test. In the light-dark box test, the FLX-treated offspring had less time in the light side than control. We also observed a low cognitive performance in the object recognition task and poor motor skill learning in the rotarod test. These findings suggest that programming with FLX during the neonatal period alters a hippocampal serotonergic system, promoting anxiety and antidepressant behavior in adults, as well as a low mnemonic capacity.


Assuntos
Ansiedade/induzido quimicamente , Ansiedade/metabolismo , Fluoxetina/toxicidade , Hipocampo/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/toxicidade , Animais , Animais Recém-Nascidos , Ansiedade/psicologia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , Feminino , Fluoxetina/administração & dosagem , Hipocampo/metabolismo , Masculino , Camundongos , Gravidez , Serotonina/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Fatores de Tempo
5.
Front Genet ; 9: 737, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30693019

RESUMO

Extreme environmental conditions are a major challenge in livestock production. Changes in climate, particularly those that contribute to weather extremes like drought or excessive humidity, may result in reduced performance and reproduction and could compromise the animal's immune function. Animal survival within extreme environmental conditions could be in response to natural selection and to artificial selection for production traits that over time together may leave selection signatures in the genome. The aim of this study was to identify selection signatures that may be involved in the adaptation of indigenous chickens from two different climatic regions (Sri Lanka = Tropical; Egypt = Arid) and in non-indigenous chickens that derived from human migration events to the generally tropical State of São Paulo, Brazil. To do so, analyses were conducted using fixation index (Fst) and hapFLK analyses. Chickens from Brazil (n = 156), Sri Lanka (n = 92), and Egypt (n = 96) were genotyped using the Affymetrix Axiom®600k Chicken Genotyping Array. Pairwise Fst analyses among countries did not detect major regions of divergence between chickens from Sri Lanka and Brazil, with ecotypes/breeds from Brazil appearing to be genetically related to Asian-Indian (Sri Lanka) ecotypes. However, several differences were detected in comparisons of Egyptian with either Sri Lankan or Brazilian populations, and common regions of difference on chromosomes 2, 3 and 8 were detected. The hapFLK analyses for the three separate countries suggested unique regions that are potentially under selection on chromosome 1 for all three countries, on chromosome 4 for Sri Lankan, and on chromosomes 3, 5, and 11 for the Egyptian populations. Some of identified regions under selection with hapFLK analyses contained genes such as TLR3, SOCS2, EOMES, and NFAT5 whose biological functions could provide insights in understanding adaptation mechanisms in response to arid and tropical environments.

6.
Dent Mater ; 31(12): 1510-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26494267

RESUMO

OBJECTIVES: In pulpal revascularization, a protective material is placed coronal to the blood clot to prevent recontamination and to facilitate osteogenic differentiation of mesenchymal stem cells to produce new dental tissues. Although mineral trioxide aggregate (MTA) has been the material of choice for clot protection, it is easily displaced into the clot during condensation. The present study evaluated the effects of recently introduced calcium silicate cements (Biodentine and TheraCal LC) on the viability and osteogenic differentiation of human dental pulp stem cells (hDPSCs) by comparing with MTA Angelus. METHODS: Cell viability was assessed using XTT assay and flow cytometry. The osteogenic potential of hDPSCs exposed to calcium silicate cements was examined using qRT-PCR for osteogenic gene expressions, alkaline phosphatase enzyme activity, Alizarin red S staining and transmission electron microscopy of extracellular calcium deposits. Parametric statistical methods were employed for analyses of significant difference among groups, with α=0.05. RESULTS: The cytotoxic effects of Biodentine and TheraCal LC on hDPSCs were time- and concentration-dependent. Osteogenic differentiation of hDPSCs was enhanced after exposure to Biodentine that was depleted of its cytotoxic components. This effect was less readily observed in hDPSCs exposed to TheraCal LC, although both cements supported extracellular mineralization better than the positive control (zinc oxide-eugenol-based cement). SIGNIFICANCE: A favorable tissue response is anticipated to occur with the use of Biodentine as a blood clot-protecting material for pulpal revascularization. Further investigations with the use of in vivo animal models are required to validate the potential adverse biological effects of TheraCal LC on hDPSCs.


Assuntos
Compostos de Alumínio/química , Bismuto/química , Compostos de Cálcio/química , Cimentos Dentários/química , Polpa Dentária/irrigação sanguínea , Polpa Dentária/citologia , Osteogênese/efeitos dos fármacos , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Células-Tronco/efeitos dos fármacos , Adolescente , Adulto , Compostos de Alumínio/toxicidade , Bismuto/toxicidade , Compostos de Cálcio/toxicidade , Sobrevivência Celular , Cimentos Dentários/toxicidade , Combinação de Medicamentos , Citometria de Fluxo , Humanos , Teste de Materiais , Óxidos/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Cimento de Óxido de Zinco e Eugenol/química , Cimento de Óxido de Zinco e Eugenol/toxicidade
7.
J Dent ; 43(5): 597-604, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25593001

RESUMO

OBJECTIVES: To evaluate the effectiveness of TRUShape® 3D Conforming Files, compared with Twisted Files, in reducing bacteria load from root canal walls, in the presence or absence of irrigant agitation. METHODS: Extracted human premolars with single oval-shaped canals were infected with Enterococcus faecalis. Teeth in Group I (N=10; NaOCl and QMix® 2in1 as respective initial and final irrigants) were subdivided into 4 subgroups: (A) TRUShape® instrumentation without irrigant activation; (B) TRUShape® instrumentation with sonic irrigant agitation; (C) Twisted Files without irrigant agitation; (D) Twisted Files with sonic irrigant agitation. To remove confounding factor (antimicrobial irrigants), teeth in Group II (N=10) were irrigated with sterile saline, using the same subgroup designations. Specimens before and after chemomechanical débridement were cultured for quantification of colony-forming units (CFUs). Data from each group were analyzed separately using two-factor ANOVA and Holm-Sidak multiple comparison (α=0.05). Canal wall bacteria were qualitatively examined using scanning electron microscopy (SEM) and light microscopy of Taylor-modified Brown and Brenn-stained demineralised sections. RESULTS: CFUs from subgroups in Group I were not significantly different (P=0.935). For Group II, both file type (P<0.001) and irrigant agitation (P<0.001) significantly affected log-reduction in CFU concentrations. The interaction of these two factors was not significant (P=0.601). Although SEM showed reduced canal wall bacteria, bacteria were present within dentinal tubules after rotary instrumentation, as revealed by light microscopy of longitudinal root sections. CONCLUSIONS: TRUShape® files removed significantly more canal wall bacteria than Twisted Files when used without an antibacterial irrigant; the latter is required to decontaminate dentinal tubules. CLINICAL SIGNIFICANCE: Root canal disinfection should not be focused only on a mechanistic approach. Rather, the rational choice of a rotary instrumentation system should be combined with the use of well-tested antimicrobial irrigants and delivery/agitation techniques to establish a clinically realistic chemomechanical débridement protocol.


Assuntos
Ligas , Instrumentos Odontológicos/microbiologia , Cavidade Pulpar/microbiologia , Preparo de Canal Radicular/instrumentação , Tratamento do Canal Radicular/instrumentação , Anti-Infecciosos/farmacologia , Carga Bacteriana , Dente Pré-Molar/microbiologia , Biguanidas/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Dentina/microbiologia , Desinfecção/instrumentação , Desinfecção/métodos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/patogenicidade , Humanos , Polímeros/farmacologia , Irrigantes do Canal Radicular/farmacologia , Preparo de Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Rotação , Hipoclorito de Sódio/farmacologia
8.
Genet Mol Res ; 9(1): 386-93, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20309824

RESUMO

Tagetes, a genus of flowering marigolds in the family Asteraceae (Compositeae), is reported to be a medicinal plant with hypotensive, spasmolytic, anti-inflammatory, antimicrobial, and antifungal properties. Tagetes minuta characteristically contains high concentrations of essential oils, flavonoids, polyphenols, and polysaccharides that interfere with DNA, causing erroneous or no PCR products. We tested and modified various standard protocols in an effort to isolate high-quality DNA from different plant tissues of T. minuta. We used sun-dried, shade-dried and fresh-leaf tissues, as well as seeds for DNA analysis. The DNA obtained from seeds and fresh-leaf tissues with a modified cetyltrimethylammonium bromide buffer protocol was of good quality, with no colored pigments and contaminants. We were able to obtain good quality DNA from fresh leaf tissues without using liquid nitrogen. A relatively large amount of DNA was also extracted from the sun- and shade-dried tissues, but its quality was not as good as that from seeds. The DNA extracted from seeds and fresh leaves was successfully amplified by PCR using arbitrary RAPD primers. The same protocol will probably be useful for extracting high-molecular weight DNA from other plant materials containing large amounts of secondary metabolites and essential oils.


Assuntos
DNA de Plantas/isolamento & purificação , Folhas de Planta/genética , Reação em Cadeia da Polimerase/métodos , Sementes/genética , Tagetes/genética , Eletroforese em Gel de Ágar , Etídio/metabolismo , Coloração e Rotulagem
9.
Int Braz J Urol ; 36(1): 29-37, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20202232

RESUMO

PURPOSE: To compare the results of percutaneous and open drainage for perinephric abscess. MATERIALS AND METHODS: The files of 86 patients who underwent drainage for perinephric abscesses from April 2001 through March 2008 were evaluated. The method of drainage for each patient was performed according to the clinical decision of the treating physician. Percutaneous tube drain (PCD) was used for drainage of the abscess in 43 patients (group 1), while the other 43 patients were managed with open drainage (group 2). Cure was defined as complete obliteration of the abscess cavity. The cure rates, complications, and hospital stay were compared between both groups. RESULTS: The study included 50 males and 36 females with mean age 44.2 + or - 17.3. The most common predisposing factors were diabetes mellitus and/or stones. Open drainage of perinephric abscesses resulted in a statistically significant higher cure rate (98% versus 69%, p < 0.001) and shorter hospital stay than PCD (3.6 versus 6 days, p < 0.001). Failure of complete drainage of multilocular abscess was observed in 8 of 13 cases (61.5%) in group 1 and one of 38 cases (2.6%) in group 2 (P < 0.001). Complications were observed in 7% of group 1 and 11.5% in group 2 (P = 0.45). After mean follow-up of 19 months, 9 of 46 patients (19.6%) had recurrence; 7 of them were in group 1. CONCLUSION: Percutaneous drainage of perinephric abscess is an effective minimally invasive treatment. However, PCD is not the optimal method for drainage of multilocular abscess because open surgical drainage provided higher cure rates and shorter hospitalization than PCD.


Assuntos
Abscesso/terapia , Drenagem/métodos , Nefropatias/terapia , Adulto , Drenagem/efeitos adversos , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Resultado do Tratamento
10.
Int. braz. j. urol ; 36(1): 29-37, Jan.-Feb. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-544071

RESUMO

Purpose: To compare the results of percutaneous and open drainage for perinephric abscess. MATERIALS AND METHODS: The files of 86 patients who underwent drainage for perinephric abscesses from April 2001 through March 2008 were evaluated. The method of drainage for each patient was performed according to the clinical decision of the treating physician. Percutaneous tube drain (PCD) was used for drainage of the abscess in 43 patients (group 1), while the other 43 patients were managed with open drainage (group 2). Cure was defined as complete obliteration of the abscess cavity. The cure rates, complications, and hospital stay were compared between both groups. Results: The study included 50 males and 36 females with mean age 44.2 ± 17.3. The most common predisposing factors were diabetes mellitus and/or stones. Open drainage of perinephric abscesses resulted in a statistically significant higher cure rate (98 percent versus 69 percent, p < 0.001) and shorter hospital stay than PCD (3.6 versus 6 days, p < 0.001). Failure of complete drainage of multilocular abscess was observed in 8 of 13 cases (61.5 percent) in group 1 and one of 38 cases (2.6 percent) in group 2 (P < 0.001). Complications were observed in 7 percent of group 1 and 11.5 percent in group 2 (P = 0.45). After mean follow-up of 19 months, 9 of 46 patients (19.6 percent) had recurrence; 7 of them were in group 1. CONCLUSIONS: Percutaneous drainage of perinephric abscess is an effective minimally invasive treatment. However, PCD is not the optimal method for drainage of multilocular abscess because open surgical drainage provided higher cure rates and shorter hospitalization than PCD.


Assuntos
Adulto , Feminino , Humanos , Masculino , Abscesso/terapia , Drenagem/métodos , Nefropatias/terapia , Drenagem/efeitos adversos , Seguimentos , Tempo de Internação , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA