15 research outputs found
Relaxant effect of Jatropha gossypiifolia L. on uterine smooth muscle
Jatropha gossypiifolia L. (Euphorbiaceae) is popularly known in Brazil as pião roxo and extensively used for hypotensive, spasmolytic and tocolytic purposes. In the present work, ethanolic extract and fractions from aerial parts of J. gossypiifolia L. were assayed for their effects on calcium-evoked uterine smooth muscle contraction. Rat uterus strips were incubated with ethanolic extract (0.1, 0.5 and 1.0 mg/ml), chloroformic fraction (0.25; 0.5 mg/ml) or aqueous fraction (0.25; 0.5 mg/ml). Ethanolic extract promoted a rightward displacement of calcium cumulative curves, as well as, reduced the maximal contractions in 27.3% and 80.3% (0.5 and 1.0 mg/ml, respectively). Clhoroformic fraction inhibited the responsiveness of uterine muscle to calcium causing the maximal contractile response to be reduced in 27.4 % and 45.1 %, respectively. On the other hand, these parameters were only slightly reduced in the presence of aqueous fraction. Taken together, our results suggest that ethanolic extract and fractions from J. gossypiifolia reduce calcium-evoked contractile response of the uterine smooth muscle, corroborating its ethnopharmacological application as tocolytic remedy
Relaxant effect of Jatropha gossypiifolia L. on uterine smooth muscle
Jatropha gossypiifolia L. (Euphorbiaceae) is popularly known in Brazil as pião roxo and extensively used for hypotensive, spasmolytic and tocolytic purposes. In the present work, ethanolic extract and fractions from aerial parts of J. gossypiifolia L. were assayed for their effects on calcium-evoked uterine smooth muscle contraction. Rat uterus strips were incubated with ethanolic extract (0.1, 0.5 and 1.0 mg/ml), chloroformic fraction (0.25; 0.5 mg/ml) or aqueous fraction (0.25; 0.5 mg/ml). Ethanolic extract promoted a rightward displacement of calcium cumulative curves, as well as, reduced the maximal contractions in 27.3% and 80.3% (0.5 and 1.0 mg/ml, respectively). Clhoroformic fraction inhibited the responsiveness of uterine muscle to calcium causing the maximal contractile response to be reduced in 27.4 % and 45.1 %, respectively. On the other hand, these parameters were only slightly reduced in the presence of aqueous fraction. Taken together, our results suggest that ethanolic extract and fractions from J. gossypiifolia reduce calcium-evoked contractile response of the uterine smooth muscle, corroborating its ethnopharmacological application as tocolytic remedy
Maturidade de Méis produzidos por Abelhas Tubi (Scaptotrigona sp.) da região Litoral Norte Maranhense
A abelha tubi (Scaptotrigona sp.) é uma espécie de abelha sem ferrão que pertence a tribo Meliponini (Hymenoptera, Apidae), encontrada principalmente nas florestas tropicais, sendo que no Brasil, há ocorrência da espécie nas regiões norte, nordeste, sudeste e centro-oeste. A falta de regulamentação técnica de identidade e padrão para a produção de mel da abelha tubi é um obstáculo para a cadeia produtiva desta espécie, uma vez que a meliponicultura é uma atividade alternativa de geração de renda de grande importância para as populações tradicionais. Com isso, visando contribuir para a avaliação da qualidade de méis de abelhas sem ferrão, este trabalho teve como objetivo avaliar os parâmetros de maturidade de amostras de méis de abelhas tubi. As análises de umidade, açúcares redutores e sacarose aparente foram realizadas no Laboratório de Macromoléculas e Produtos Naturais da Universidade Estadual do Maranhão. Conforme os resultados obtidos para os parâmetros de maturidade, as amostras de méis apresentaram percentual médio total de umidade de 26,29 % ± 1,47, para açúcares redutores a média total encontrada foi de 53,97 g.100 g-1 ± 2,71 e para a sacarose aparente, o valor médio total obtido foi de 6,29 g.100 g-1 ± 2,97, variando de 2,84 a 11,19 g.100 g-1. Observou-se que os resultados encontrados estão compatíveis com os padrões estabelecidos para mel de meliponíneos do Brasil. Os méis das abelhas sem ferrão tubi apresentam composição e características químicas próprias da espécie
Naturally Occurring Acetylcholinesterase Inhibitors and Their Potential Use for Alzheimer's Disease Therapy
Alzheimer's disease (AD) is a main cause of dementia, accounting for up to 75% of all dementia cases. Pathophysiological processes described for AD progression involve neurons and synapses degeneration, mainly characterized by cholinergic impairment. This feature makes acetylcholinesterase inhibitors (AChEi) the main class of drugs currently used for the treatment of AD dementia phase, among which galantamine is the only naturally occurring substance. However, several plant species producing diverse classes of alkaloids, coumarins, terpenes, and polyphenols have been assessed for their anti-AChE activity, becoming potential candidates for new anti-AD drugs. Therefore, this mini-review aimed to recapitulate last decade studies on the anti-AChE activity of plant species, their respective extracts, as well as isolated compounds. The anti-AChE activity of extracts prepared from 54 plant species pertaining 29 families, as well as 36 isolated compounds were classified and discussed according to their anti-AChE pharmacological potency to highlight the most prominent ones. Besides, relevant limitations, such as proper antioxidant assessment, and scarcity of toxicological and clinical studies were also discussed in order to help researchers out with the bioprospection of potentially new AChEi
Corrigendum to “Cross-sectional analysis of students and school workers reveals a high number of asymptomatic SARS-CoV-2 infections during school reopening in Brazilian cities” [Heliyon 8 (11) (November 2022) Article e11368]
Cross-sectional analysis of students and school workers reveals a high number of asymptomatic SARS-CoV-2 infections during school reopening in Brazilian cities
Brazil experienced one of the most prolonged periods of school closures, and reopening could have exposed students to high rates of SARS-CoV-2 infection. However, the infection status of students and school workers at the time of the reopening of schools located in Brazilian cities is unknown. Here we evaluated viral carriage by RT-PCR and seroprevalence of anti-SARS-CoV-2 antibodies (IgM and IgG) by immunochromatography in 2259 individuals (1139 students and 1120 school workers) from 28 schools in 28 Brazilian cities. We collected the samples within 30 days after public schools reopened and before the start of vaccination campaigns. Most students (n = 421) and school workers (n = 446) had active (qRT-PCR + IgM− IgG− or qRT-PCR + IgM + IgG−/+) SARS-CoV-2 infection. Regression analysis indicated a strong association between the infection status of students and school workers. Furthermore, while 45% (n = 515) of the students and 37% (n = 415) of the school workers were neither antigen nor antibody positive in laboratory tests, 16% of the participants (169 students and 193 school workers) were oligosymptomatic, including those reinfected. These individuals presented mild symptoms such as headache, sore throat, and cough. Notably, most of the individuals were asymptomatic (83.9%). These results indicate that many SARS-CoV-2 infections in Brazilian cities during school reopening were asymptomatic. Thus, our study highlights the need to promote a coordinated public health effort to guarantee a safe educational environment while avoiding exacerbating pre-existent social inequalities in Brazil, reducing social, mental, and economic losses for students, school workers, and their families
Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.
BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca
Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
Background
A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials.
Methods
This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674.
Findings
Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation.
Interpretation
ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials
Naturally Occurring Acetylcholinesterase Inhibitors and Their Potential Use for Alzheimer's Disease Therapy
Development and in vivo evaluation of the moisturising potential of cosmetic formulations containing Babassu (Orbignya phalerata Martius) oily extract
The objective of this study was to use oily extracts of the species Orbignya phalerata Martius (Babassu) from three ecological regions in Maranhão state, Brazil: Forest (BBF), Coast (BBC) and Lowlands (BBL) to develop cosmetic formulations. Formulations with 10 wt% of Babassu oily extracts were characterised regarding their stability for 30 days (separation of phases after centrifugation, pH, density, viscosity and droplets size distribution) and evaluation of efficacy in vivo by cutaneous biometry. Results indicated that the formulations were physically stable and presented pseudo-plastic fluid behavior as evaluated by rheology. Concerning the in vivo efficacy assays, the formulation containing BBL increased the hydration of the volunteers’skin when compared to a formulation containing only a commercial standard moisturising ingredient, without altering the skin pH. BBL showed to be a promising ingredient to cosmetics, behaving as an excellent moisturiser likely because it contains the highest amounts of lauric, myristic and oleic acids that present great emollient potential