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1.
Reprod Health ; 20(1): 172, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37990327

RESUMO

PURPOSE: The COVID-19 pandemic led to major service disruptions in the healthcare sector, especially regarding sexual and reproductive health services. However, the impact of the pandemic on Canadian adolescents is relatively unknown. This study aimed to investigate the impacts of the COVID-19 pandemic and associated public health measures on the sexual and reproductive health (SRH) of adolescents in Alberta, Canada. METHODS: A qualitative study using an interpretive description (ID) approach and community-based participatory research principles was conducted to capture the subjective experience and perceptions of adolescents and service providers. With the collaboration of the Adolescent Advisory Group and community partners, 18 adolescents and 15 service providers were recruited for the study through purposive sampling. Findings from the qualitative interviews were analyzed using thematic analysis. RESULTS: Three major themes emerged from the analysis: (1) COVID-19 SRH experience, (2) barriers to SRH, and (3) adolescent SRH strategies. Our findings highlight numerous barriers and challenges that prevented adolescents from accessing SRH education, products, and services. CONCLUSION: The COVID-19 pandemic had a profound impact on the SRH and the well-being of adolescents. Our study reflects the need for diverse SRH strategies to maintain continued access to SRH resources during disruptive events, such as the pandemic.


Access to sexual and reproductive health (SRH) services is a basic human right. All individuals require access to appropriate SRH services to maintain their optimal sexual and reproductive health. Adolescents require special guidance, support, and youth-friendly services in matters of SRH as they enter puberty and explore their sexual identity. However, during the COVID-19 pandemic, many health and SRH services were suspended. Access to SRH products and services became difficult due to public health restrictions, which has possible negative consequences for adolescents' SRH. The experiences of adolescents during the COVID-19 pandemic regarding their SRH are not reported in Alberta, Canada. Therefore, we explored the impacts of these public health restrictions on adolescents' SRH. We performed qualitative interviews with adolescents and SRH service providers to know their perspectives on how the pandemic influenced the SRH of adolescents. This paper provides insights into the barriers faced by adolescents while accessing SRH services during the pandemic, as well as their perceptions of digital strategies, such as mobile applications, and other recommendations for supporting SRH education and services. Based on the study findings, an adolescent-friendly mobile application will be developed to provide a virtual platform connecting adolescents to SRH educational resources, services, and support.


Assuntos
COVID-19 , Serviços de Saúde Reprodutiva , Adolescente , Humanos , Saúde Reprodutiva/educação , Pandemias , Alberta/epidemiologia , COVID-19/epidemiologia , Comportamento Sexual
2.
Molecules ; 27(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296407

RESUMO

(1) Background: An earlier study on the hypoglycemic activity of S. polyanthum (Wight.) leaf methanol extract identified squalene as the major chemical compound. The present study was conducted to assess the hypoglycemic effect of fractions and subfractions of the methanol extract of S. polyanthum compared to the squalene using a bioassay-guided in vivo study. (2) Methods: The methanol extract was fractionated using the liquid−liquid fractionation method. Streptozotocin-induced type 1 diabetic rat was used to study the hypoglycemic effect. (3) Results: The findings showed that chloroform fraction significantly (p < 0.05) lowered blood glucose levels of diabetic rats as compared to the control. Further fractionation of chloroform fraction yielded subfraction-1 and -2, whereby subfraction-1 exhibited a higher blood-glucose-lowering effect. The lipid profile test showed that the total cholesterol level of subfraction-1 and squalene-treated groups decreased significantly (p < 0.05). An immunohistochemistry study revealed that none of the treatments regenerated pancreatic ß-cells. Gas chromatography−mass spectrophotometer analysis identified the presence of squalene in the active methanol extract, chloroform fraction, and subfraction-1. In silico analysis revealed a higher affinity of squalene against protein receptors that control lipid metabolism than metformin. (4) Conclusions: Data obtained from the present work suggested the crude methanol extract exerted the highest hypoglycemic effect compared to fraction, subfraction, and squalene, confirming synergistic effect may be responsible for the hypoglycemic activity of S. polyanthum.


Assuntos
Diabetes Mellitus Experimental , Metformina , Syzygium , Ratos , Animais , Syzygium/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Estreptozocina , Diabetes Mellitus Experimental/metabolismo , Glicemia , Metanol/química , Clorofórmio , Esqualeno , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Lipídeos , Colesterol
3.
BMC Complement Altern Med ; 19(1): 152, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253153

RESUMO

BACKGROUND: The leaves of Gongronema latifolium Benth. have long been recognized traditionally as a remedy for a variety of ailments in Africa. This study was conducted to evaluate the safety profile of the ethanolic extract of G. latifolium (GLES) leaves through a repeated dose 90-day oral toxicity study in male and female of Sprague Dawley rats. METHODS: GLES was orally administered at doses of 250, 500 and 1000 mg/kg/day consecutively for 90 days. RESULTS: No behavioral or physiological changes and mortality were observed. GLES did not have a marked impact on general hematological parameters and did not precipitate nephrotoxicity. However, compared to the control, serum triglycerides, total cholesterol and low-density lipoprotein levels were lower and white adipose tissue paired retroperitoneal fat depots were depleted in male rats treated with GLES3 by the end of the experiment. The liver was significantly enlarged in GLES-treated rats of both sexes. Negative gender-specific alterations were observed with the highest dose. Adverse risk was evident in the female rats mainly due to marked body weight gain and cerebrum weight reduction. CONCLUSION: Further research is needed to reach more specific conclusions about to the safety of ingesting high doses of GLES for long periods of time.


Assuntos
Apocynaceae/química , Extratos Vegetais/administração & dosagem , Tecido Adiposo Branco/efeitos dos fármacos , Administração Oral , Animais , Feminino , Fígado/efeitos dos fármacos , Masculino , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
4.
BMC Complement Altern Med ; 18(1): 262, 2018 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261874

RESUMO

After the publication of this article [1] it came to our attention that one author, Boon Yin Khoo, was erroneously omitted from the authorship list.

5.
Pharm Biol ; 55(1): 2083-2094, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28832263

RESUMO

CONTEXT: Vernonia amygdalina Del. (VA) (Asteraceae) is commonly used to treat hypertension in Malaysia. OBJECTIVE: This study investigates the vasorelaxant mechanism of VA ethanol extract (VAE) and analyzes its tri-step FTIR spectroscopy fingerprint. MATERIALS AND METHODS: Dried VA leaves were extracted with ethanol through maceration and concentrated using rotary evaporator before freeze-dried. The vasorelaxant activity and the underlying mechanisms of VAE using the cumulative concentration (0.01-2.55 mg/mL at 20-min intervals) were evaluated on aortic rings isolated from Sprague Dawley rats in the presence of antagonists. RESULTS: The tri-step FTIR spectroscopy showed that VAE contains alkaloids, flavonoids, and saponins. VAE caused the relaxation of pre-contracted aortic rings in the presence and absence of endothelium with EC50 of 0.057 ± 0.006 and 0.430 ± 0.196 mg/mL, respectively. In the presence of Nω-nitro-l-arginine methyl ester (EC50 0.971 ± 0.459 mg/mL), methylene blue (EC50 1.203 ± 0.426 mg/mL), indomethacin (EC50 2.128 ± 1.218 mg/mL), atropine (EC50 0.470 ± 0.325 mg/mL), and propranolol (EC50 0.314 ± 0.032 mg/mL), relaxation stimulated by VAE was significantly reduced. VAE acted on potassium channels, with its vasorelaxation effects significantly reduced by tetraethylammonium, 4-aminopyridine, barium chloride, and glibenclamide (EC50 0.548 ± 0.184, 0.158 ± 0.012, 0.847 ± 0.342, and 0.304 ± 0.075 mg/mL, respectively). VAE was also found to be active in reducing Ca2+ released from the sarcoplasmic reticulum and blocking calcium channels. CONCLUSIONS: The vasorelaxation effect of VAE involves upregulation of NO/cGMP and PGI2 signalling pathways, and modulation of calcium/potassium channels, and muscarinic and ß2-adrenergic receptor levels.


Assuntos
Aorta Torácica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Vernonia , Animais , Aorta Torácica/fisiologia , Relação Dose-Resposta a Droga , Etanol/farmacologia , Masculino , Técnicas de Cultura de Órgãos , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Ratos , Ratos Sprague-Dawley , Vasodilatação/fisiologia , Vasodilatadores/isolamento & purificação
6.
Molecules ; 21(4): 495, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27092479

RESUMO

This paper is a review on the types of antagonists and the signaling mechanism pathways that have been used to determine the mechanisms of action employed for vasodilation by test compounds. Thus, we exhaustively reviewed and analyzed reports related to this topic published in PubMed between the years of 2010 till 2015. The aim of this paperis to suggest the most appropriate type of antagonists that correspond to receptors that would be involved during the mechanistic studies, as well as the latest signaling pathways trends that are being studied in order to determine the route(s) that atest compound employs for inducing vasodilation. The methods to perform the mechanism studies were included. Fundamentally, the affinity, specificity and selectivity of the antagonists to their receptors or enzymes were clearly elaborated as well as the solubility and reversibility. All the signaling pathways on the mechanisms of action involved in the vascular tone regulation have been well described in previous review articles. However, the most appropriate antagonists that should be utilized have never been suggested and elaborated before, hence the reason for this review.


Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Humanos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Transdução de Sinais/efeitos dos fármacos , Vasodilatadores/química
7.
BMC Complement Altern Med ; 14: 426, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25358757

RESUMO

BACKGROUND: This study evaluated the impact of Vernonia amygdalina (VA) on the transcription of key enzymes involved in cellular modulation of glucose in streptozotocin-induced diabetic rats in a bid to understand the possible anti-diabetic mechanism of VA. METHODS: The chloroform fraction of VA (200 mg/kg and 400 mg/kg body weight) was administered to SDRs for 7 and 14 days. Thereafter, the expression (transcription) of key carbohydrate regulatory genes was evaluated in selected tissues - adipose, muscle and liver. Also, the body weight and blood glucose changes were monitored. RESULTS: A 14-day administration of 200 mg and 400 mg of the extract and metformin (500 mg/kg) showed a striking decrease (P <0.05) in the expression of the gluconeogenic enzymes - fructose 1,6-bisphosphatase, phosphoenol pyruvate carboxykinase and glucose 6-phosphatase in the liver and muscle compared to the diabetic control. These genes were highly expressed in tissues of untreated diabetic rats (P <0.05) indicating severe gluconeogenesis. Furthermore, the extract as well as metformin significantly increased glucose oxidation via the pentose phosphate pathway (PPP) i.e. increased expression of the glucose 6-phosphate dehydrogenase (G6PDH) gene (P <0.05) in the liver. Conversely, the expression of the G6PDH in the muscle and adipose tissues significantly decreased (P <0.05), suggesting enhanced utilization of NADPH and ribose in the clearance of reactive oxygen species and for expression of other relevant genes respectively. Also, transcription of the cell proliferation regulatory enzyme, phosphatidylinositol 3-kinase increased in the liver, but decreased in the muscle and adipose tissues (P <0.05) upon treatment with the extract or metformin, implying that the liver responded to the VA and metformin treatments more than other organs. The extract administration also caused a decrease in the expression of key enzymes of glycolysis namely hexokinase and phosphofructokinase, suggestive of a glucose sparing for ribose and NADPH production in PPP. CONCLUSION: Overall, data obtained in this study suggest that VA exerts little or no effect on glycolysis; rather, it may achieve its anti-diabetic action by a simultaneous suppression of gluconeogenesis and potentiation of glucose oxidation via PPP pathway, almost exclusively in the liver.


Assuntos
Diabetes Mellitus Experimental/enzimologia , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Fígado/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vernonia , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Expressão Gênica , Glucose-6-Fosfatase/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glicólise/efeitos dos fármacos , Hexoquinase/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Fígado/enzimologia , Fígado/metabolismo , Masculino , Músculos/metabolismo , Oxirredução , Fosfatidilinositol 3-Quinases/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos
8.
BMC Complement Altern Med ; 14: 220, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-24993916

RESUMO

BACKGROUND: Recently, there has been increasing interest in Ficus deltoidea Jack. (Moraceae) due to its chemical composition and the potential health benefits. The present study was undertaken to investigate the effect of extracts of F. deltoidea leaves on diabetes. METHODS: The petroleum ether, chloroform and methanol extracts of F. deltoidea were prepared and subjected to standardization using preliminary phytochemical and HPLC analysis. Dose selection was made on the basis of acute oral toxicity study (50-5000 mg/kg b. w.) as per OECD guidelines. Diabetes mellitus was induced with streptozotocin and rats found diabetic were orally administered with the extract (250, 500 and 1000 mg/kg) for 14 days. Levels of blood glucose and insulin were measured in control as well as diabetic rats on 0, 7 and 14th day. In addition, glucose metabolism regulating gene expression was assessed using RT-PCR. RESULTS: HPLC analysis revealed that the methanol extract is enriched with C-glycosylflavones particularly, vitexin and isovitexin. In oral glucose tolerance test, oral administration of the methanol extract increased the glucose tolerance. The methanol extract showed significant (P < 0.01) antidiabetic activity. The extract treatment caused significant reduction (p < 0.01) in elevated fasting blood glucose level in streptozotocin-induced diabetic rats. The streptozotocin-related weight loss in rats was noticeably reversed by the extract treatment. Finally, RT-PCR analysis revealed a novel mechanisms for the anti-diabetic action of methanol extract of F. deltoidea. The extract exerted its effect via an increase of insulin secretion which impeded the hepatic glucose production, via down-regulation of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase genes expression on one hand, and up-regulation of hepatic GK and PPARγ genes expression on the other hand. The extract caused an increased expression of GLUT-4 gene expression in skeletal muscles which leads to normalize the hyperglycemia. The extract also nullified the toxic effects of streptozitocin by blocking its entry into the islet ß-cells through reducing the expression of GLUT-2 gene. CONCLUSION: It can be concluded that, F. deltoidea could potentially inhibits the streptozitocin-induced hyperglycemia in rats. Further the herb can be utilized as useful remedy for alleviation of diabetes complications.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Ficus/química , Glucose/biossíntese , Insulina/metabolismo , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/sangue , Secreção de Insulina , Fígado/química , Fígado/metabolismo , Masculino , Extratos Vegetais/química , Folhas de Planta/química , Ratos , Ratos Sprague-Dawley
9.
ACS Appl Mater Interfaces ; 16(13): 16580-16588, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38529895

RESUMO

Nonfullerene acceptors (NFAs) have dramatically improved the power conversion efficiency (PCE) of organic photovoltaics (OPV) in recent years; however, their device stability currently remains a bottleneck for further technological progress. Photocatalytic decomposition of nonfullerene acceptor molecules at metal oxide electron transport layer (ETL) interfaces has in several recent reports been demonstrated as one of the main degradation mechanisms for these high-performing OPV devices. While some routes for mitigating such degradation effects have been proposed, e.g., through a second layer integrated on the ETL surface, no clear strategy that complies with device scale-up and application requirements has been presented to date. In this work, it is demonstrated that the development of sputtered titanium oxide layers as ETLs in nonfullerene acceptor based OPV can lead to significantly enhanced device lifetimes. This is achieved by tuning the concentration of defect states at the oxide surface, via the reactive sputtering process, to mitigate the photocatalytic decomposition of NFA molecules at the metal oxide interlayers. Reduced defect state formation at the oxide surface is confirmed through X-ray photoelectron spectroscopy (XPS) studies, while the reduced photocatalytic decomposition of nonfullerene acceptor molecules is confirmed via optical spectroscopy investigations. The PBDB-T:ITIC organic solar cells show power conversion efficiencies of around 10% and significantly enhanced photostability. This is achieved through a reactive sputtering process that is fully scalable and industry compatible.

10.
BMC Complement Altern Med ; 13: 39, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23425283

RESUMO

BACKGROUND: One vital therapeutic approach for the treatment of type 2 diabetes mellitus is the use of agents that can decrease postprandial hyperglycaemia by inhibiting carbohydrate digesting enzymes. The present study investigated the effects of bioassay-guided extract and fractions of the dried fruit pericarp of Phaleria macrocarpa, a traditional anti-diabetic plant, on α-glucosidase and α-amylase, in a bid to understand their anti-diabetic mechanism, as well as their possible attenuation action on postprandial glucose increase. METHODS: Methanol extract (ME), obtained by successive solvent extraction, its most effective liquid-liquid n-butanol fraction (NBF) and the flash column chromatographic sub-fraction (SFI), were evaluated for in vitro α-glucosidase (yeast) and α-amylase (porcine) activity inhibition. Furthermore, confirmatory in vivo tests were carried out in streptozotocin-induced diabetic rats (SDRs) using oral glucose, sucrose and starch tolerance tests. RESULTS: At the highest concentration employed (100 µg/ml), NBF showed highest inhibition against α-glucosidase (75%) and α-amylase (87%) in vitro (IC50 = 2.40 ± 0.23 µg/ml and 58.50 ± 0.13 µg/ml, respectively) in a dose-dependent fashion; an effect found to be about 20% higher than acarbose (55%), a standard α-glucosidase inhibitor (IC50 = 3.45 ± 0.19 µg/ml). The ME and SFI also inhibited α-glucosidase (IC50 = 7.50 ± 0.15 µg/ml and 11.45 ± 0.28 µg/ml) and α-amylase (IC50 = 43.90 ± 0.19 µg/ml and 69.80 ± 0.25 µg/ml), but to a lesser extent. In in vivo studies with diabetic rats, NBF and SFI effectively reduced peak blood glucose (PBG) by 15.08% and 6.46%, and the area under the tolerance curve (AUC) by 14.23% and 12.46%, respectively, after an oral sucrose challenge (P < 0.05); thereby validating the observed in vitro action. These reduction effects on PBG and AUC were also demonstrated in glucose and starch tolerance tests, but to a lesser degree. CONCLUSIONS: These findings reveal that P. macrocarpa can attenuate hyperglycaemia in both in vitro and in vivo conditions by potently inhibiting carbohydrate hydrolysing enzymes, making it a viable plant for sourcing natural compounds for the management of type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Carboidratos da Dieta/metabolismo , Inibidores de Glicosídeo Hidrolases , Hiperglicemia/prevenção & controle , Extratos Vegetais/uso terapêutico , Thymelaeaceae , alfa-Amilases/antagonistas & inibidores , Animais , Área Sob a Curva , Glicemia/metabolismo , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Digestão/efeitos dos fármacos , Relação Dose-Resposta a Droga , Frutas , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Sacarose/metabolismo
11.
ACS Appl Mater Interfaces ; 15(47): 55065-55072, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37972316

RESUMO

The implementation of sputter-deposited TiOx as an electron transport layer in nonfullerene acceptor-based organic photovoltaics has been shown to significantly increase the long-term stability of devices compared to conventional solution-processed ZnO due to a decreased photocatalytic activity of the sputtered TiOx. In this work, we utilize synchrotron-based photoemission and absorption spectroscopies to investigate the interface between the electron transport layer, TiOx prepared by magnetron sputtering, and the nonfullerene acceptor, ITIC, prepared in situ by spray deposition to study the electronic state interplay and defect states at this interface. This is used to unveil the mechanisms behind the decreased photocatalytic activity of the sputter-deposited TiOx and thus also the increased stability of the organic solar cell devices. The results have been compared to similar measurements on anatase TiOx since anatase TiOx is known to have a strong photocatalytic activity. We show that the deposition of ITIC on top of the sputter-deposited TiOx results in an oxidation of Ti3+ species in the TiOx and leads to the emergence of a new O 1s peak that can be attributed to the oxygen in ITIC. In addition, increasing the thickness of ITIC on TiOx leads to a shift in the O 1s and C 1s core levels toward higher binding energies, which is consistent with electron transfer at the interface. Resonant photoemission at the Ti L-edge shows that oxygen vacancies in sputtered TiOx lie mostly in the surface region, which contrasts the anatase TiOx where an equal distribution between surface and subsurface oxygen vacancies is observed. Furthermore, it is shown that the subsurface oxygen vacancies in sputtered TiOx are strongly reduced after ITIC deposition, which can reduce the photocatalytic activity of the oxide, while the oxygen vacancies in model anatase TiOx are not affected upon ITIC deposition. This difference can explain the inferior photocatalytic activity of the sputter-deposited TiOx and thus also the increased stability of devices with sputter-deposited TiOx used as an electron transport layer.

12.
Regul Toxicol Pharmacol ; 63(1): 106-14, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22440551

RESUMO

Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.


Assuntos
Cactaceae , Frutas , Extratos Vegetais/toxicidade , Animais , Creatinina/sangue , Feminino , Dose Letal Mediana , Masculino , Metais Pesados/análise , Metanol/química , Extratos Vegetais/análise , Ratos , Ratos Sprague-Dawley , Soroglobulinas/análise , Solventes/química , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica , Ureia/sangue
13.
Sensors (Basel) ; 12(7): 9603-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23012561

RESUMO

The stepping forces of normal and Freund Complete Adjuvant (FCA)-induced arthritic rats were studied in vivo using a proposed novel analgesic meter. An infrared charge-coupled device (CCD) camera and a data acquisition system were incorporated into the analgesic meter to determine and measure the weight of loads on the right hind paw before and after induction of arthritis by FCA injection into the paw cavity. FCA injection resulted in a significant reduction in the stepping force of the affected hind paw. The stepping force decreased to the minimum level on day 4 after the injection and then gradually increased up to day 25. Oral administration of prednisolone significantly increased the stepping forces of FCA-induced arthritic rats on days 14 and 21. These results suggest that the novel device is an effective tool for measuring the arthritic pain in in vivo studies even though walking is a dynamic condition.

14.
Molecules ; 17(5): 4986-5002, 2012 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-22547320

RESUMO

An earlier anti-hyperglycemic study with serial crude extracts of Phaleria macrocarpa (PM) fruit indicated methanol extract (ME) as the most effective. In the present investigation, the methanol extract was further fractionated to obtain chloroform (CF), ethyl acetate (EAF), n-butanol (NBF) and aqueous (AF) fractions, which were tested for antidiabetic activity. The NBF reduced blood glucose (p < 0.05) 15 min after administration, in an intraperitoneal glucose tolerance test (IPGTT) similar to metformin. Moreover, it lowered blood glucose in diabetic rats by 66.67% (p < 0.05), similar to metformin (51.11%), glibenclamide (66.67%) and insulin (71.43%) after a 12-day treatment, hence considered to be the most active fraction. Further fractionation of NBF yielded sub-fractions I (SFI) and II (SFII), and only SFI lowered blood glucose (p < 0.05), in IPGTT similar to glibenclamide. The ME, NBF, and SFI correspondingly lowered plasma insulin (p < 0.05) and dose-dependently inhibited glucose transport across isolated rat jejunum implying an extra-pancreatic mechanism. Phytochemical screening showed the presence of flavonoids, terpenes and tannins, in ME, NBF and SFI, and LC-MS analyses revealed 9.52%, 33.30% and 22.50% mangiferin respectively. PM fruit possesses anti-hyperglycemic effect, exerted probably through extra-pancreatic action. Magniferin, contained therein may be responsible for this reported activity.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Frutas/química , Fitoterapia , Extratos Vegetais/administração & dosagem , Thymelaeaceae/química , Animais , Bioensaio , Transporte Biológico , Glicemia/análise , Fracionamento Químico , Diabetes Mellitus Experimental/metabolismo , Feminino , Teste de Tolerância a Glucose , Glibureto/administração & dosagem , Glibureto/química , Glibureto/uso terapêutico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Jejuno/metabolismo , Masculino , Metformina/administração & dosagem , Metformina/química , Metformina/uso terapêutico , Metanol/química , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Solventes/química
15.
Ocul Immunol Inflamm ; 30(2): 355-356, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33021419

RESUMO

Endophthalmitis caused by Abiotrophia defectiva has never before been reported in a child. We report a case of a 12-year-old female with a history of penetrating keratoplasty, followed years later by open globe injury and repair, and subsequent anterior vitrectomy, which resulted in endophthalmitis caused by Abiotrophia defectiva. We review previous cases of endophthalmitis by this organism and argue that its detection will become more common with the use of 16S rDNA PCR and MALDI-TOF mass spectrometry.


Assuntos
Abiotrophia , Endoftalmite , Infecções por Bactérias Gram-Positivas , Criança , Endoftalmite/diagnóstico , Endoftalmite/etiologia , Feminino , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Vitrectomia/efeitos adversos
16.
Sensors (Basel) ; 11(5): 5058-70, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163890

RESUMO

Behavioural assessment of experimental pain is an essential method for analysing and measuring pain levels. Rodent models, which are widely used in behavioural tests, are often subject to external forces and stressful manipulations that cause variability of the parameters measured during the experiment. Therefore, these parameters may be inappropriate as indicators of pain. In this article, a stepping-force analgesimeter was designed to investigate the variations in the stepping force of rats in response to pain induction. The proposed apparatus incorporates new features, namely an infrared charge-coupled device (CCD) camera and a data acquisition system. The camera was able to capture the locomotion of the rats and synchronise the stepping force concurrently so that each step could be identified. Inter-day and intra-day precision and accuracy of each channel (there were a total of eight channels in the analgesimeter and each channel was connected to one load cell and one amplifier) were studied using different standard load weights. The validation studies for each channel also showed convincing results whereby intra-day and inter-day precision were less than 1% and accuracy was 99.36-100.36%. Consequently, an in vivo test was carried out using 16 rats (eight females and eight males). The rats were allowed to randomly walk across the sensor tunnel (the area that contained eight channels) and the stepping force and locomotion were recorded. A non-expert, but from a related research domain, was asked to differentiate the peaks of the front and hind paw, respectively. The results showed that of the total movement generated by the rats, 50.27 ± 3.90% in the case of the male rats and 62.20 ± 6.12% in that of the female rats had more than two peaks, a finding which does not substantiate the assumptions made in previous studies. This study also showed that there was a need to use the video display frame to distinguish between the front and hind paws in the case of 48.80 ± 4.01% of the male rats and 66.76 ± 5.35% of the female rats. Evidently the assumption held by current researchers regarding stepping force measurement is not realistic in terms of application, and as this study has shown, the use of a video display frame is essential for the identification of the front and hind paws through the peak signals.


Assuntos
Artrite/fisiopatologia , Técnicas Biossensoriais/instrumentação , Medição da Dor/instrumentação , Animais , Técnicas Biossensoriais/métodos , Feminino , Locomoção/fisiologia , Masculino , Medição da Dor/métodos , Ratos
17.
Molecules ; 15(12): 9008-23, 2010 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-21150821

RESUMO

Gynura procumbens (Lour.) Merr (family Compositae) is cultivated in Southeast Asia, especially Indonesia, Malaysia and Thailand, for medicinal purposes. This study evaluated the in vivo hypoglycemic properties of the water extract of G. procumbens following 14 days of treatment and in vitro in RIN-5F cells. Glucose absorption from the intestines and its glucose uptake in abdominal skeletal muscle were assessed. The antidiabetic effect of water extract of G. procumbens leaves was investigated in streptozotocin-induced diabetic rats. The intraperitoneal glucose tolerance test (IPGTT) was performed in diabetic rats treated with G. procumbens water extract for 14 days. In the IPGTT, blood was collected for insulin and blood glucose measurement. After the IPGTT, the pancreases were collected for immunohistochemical study of ß-cells of the islets of Langerhans. The possible antidiabetic mechanisms of G. procumbens were assessed through in vitro RIN-5F cell study, intestinal glucose absorption and glucose uptake by muscle. The results showed that G. procumbens significantly decreased blood glucose levels after 14 days of treatment and improved outcome of the IPGTT. However, G. procumbens did not show a significant effect on insulin level either in the in vivo test or the in vitro RIN-5F cell culture study. G. procumbens also showed minimal effects on ß-cells of the islets of Langerhans in the pancreas. However, G. procumbens only significantly increased glucose uptake by muscle tissues. From the findings we can conclude that G. procumbens water extract exerted its hypoglycemic effect by promoting glucose uptake by muscles.


Assuntos
Asteraceae/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Água/química
18.
J AAPOS ; 23(2): 90.e1-90.e6, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30772472

RESUMO

PURPOSE: To compare the characteristics of infants whose retinopathy of prematurity (ROP) resolves in <50 weeks with those of infants whose ROP resolves in >50 weeks' postmenstrual age (PMA) in order to identify which infants are at risk for delayed resolution and to evaluate whether severe ROP developed after 50 weeks' PMA. METHODS: The medical records of infants screened for ROP from January 2008 to December 2016 at a tertiary care facility were reviewed retrospectively. Infants without follow-up prior to ROP resolution or complete retinal vascularization and those with retinal detachment were excluded. Delayed resolution of ROP was defined as presence of immature retinal vasculature at ≥50 weeks' PMA. The birth characteristics, neonatal complications, and ROP characteristics of infants with and without delayed resolution were compared. RESULTS: A total of 996 infants were included, of whom 136 (13.6%) showed delayed resolution. Increasing severity of ROP (higher stage, lower zone, plus/pre-plus disease) and type 2 ROP was associated with delayed resolution (P < 0.05). Other variables associated with delayed resolution included <28 weeks gestational age, ≤3rd percentile birth weight, positive blood culture sepsis, necrotizing enterocolitis, intraventricular hemorrhage, and bronchopulmonary dysplasia (P < 0.05). No infants developed type 1 after 50 weeks' PMA. After a prolonged follow-up course consistent with AAP guidelines, a single patient in our study cohort was treated at 81 weeks' PMA for persistent type 2 ROP. CONCLUSIONS: In our cohort, delayed resolution of ROP was more likely in infants with more severe ROP or a complex neonatal course. No patient with delayed resolution developed type 1 ROP after 50 weeks' PMA, supporting AAP guidelines.


Assuntos
Retinopatia da Prematuridade/fisiopatologia , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Exame Físico , Remissão Espontânea , Retinopatia da Prematuridade/complicações , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
19.
J Ethnopharmacol ; 232: 135-144, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30543913

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Citrus reticulatae Pericarpium (Chen pi) was widely used as an important ingredient in the prescription of TCM to treat phlegm fluid retention type hypertension. Since Chen pi is involved in treatment as antihypertensive TCM formula, we have reasonable expectation in believing that it might possess vasorelaxant activity. AIM OF THE STUDY: This study is designed to investigate the vasorelaxant effect of Chen pi and to study its pharmacology effects. MATERIALS AND METHODS: The vasorelaxant effect of water extract of Chen pi (CRW) were evaluated on thoracic aortic rings isolated from Sprague Dawley rats. The fingerprint of Chen pi and the extracts were developed with quantification of hesperidin content by HPTLC. RESULTS: CRW exhibited the strongest vasorelaxant activity. CRW caused the relaxation of the phenylephrine pre-contracted aortic rings in the presence and absence of endothelium as well as in potassium chloride pre-contracted endothelium-intact aortic ring. The incubation of propranolol (ß-adrenergic receptor blocker), atropine (muscarinic receptor blocker), Nω-nitro-L-arginine methyl ester (NO synthase inhibitor), ODQ (sGC inhibitor), indomethacin (COX inhibitor), 4-aminopyridine (KV blocker), barium chloride (Kir blocker), and glibenclamide (KATP blocker) significantly reduced the vasorelaxant effects of CRW. CRW was also found to be active in reducing Ca2+ releases from the sarcoplasmic reticulum and suppressing the voltage-operated calcium channels. CONCLUSION: The vasorelaxant effect of CRW on rat aorta involves NO/sGC, calcium and potassium channels, muscarinic and ß-adrenergic receptors.


Assuntos
Aorta Torácica/efeitos dos fármacos , Citrus , Extratos Vegetais/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta Torácica/fisiologia , Canais de Cálcio/fisiologia , Citrus/química , Técnicas In Vitro , Masculino , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Canais de Potássio/fisiologia , Ratos Sprague-Dawley , Receptores Adrenérgicos beta/fisiologia , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/fisiologia , Vasodilatadores/química
20.
J Med Food ; 21(3): 289-301, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29420109

RESUMO

The seeds of Swietenia macrophylla King (SM) (Meliaceae) are used as a folk medicine for the treatment of hypertension in Malaysia. However, the antihypertensive and vasorelaxant effects of SM seeds are still not widely studied. Thus, this study was designed to investigate the in vivo antihypertensive effects and in vitro mechanism of vasorelaxation of a 50% ethanolic SM seed extract (SM50) and the fingerprint of SM50 was developed through tri-step Fourier transform infrared (FTIR) spectroscopy. The vasorelaxant activity and the underlying mechanisms of SM50 were evaluated on thoracic aortic rings isolated from Sprague-Dawley rats in the presence of antagonists. The pharmacological effect of SM50 was investigated by oral administration of spontaneously hypertensive rats (SHRs) with three different doses of SM50 (1000, 500, and 250 mg/kg/day) for 4 weeks and their systolic blood pressure (SBP) and diastolic blood pressure (DBP) values were measured weekly using tail-cuff method. The tri-step FTIR macro-fingerprint of SM50 showed that SM50 contains stachyose, flavonoids, limonoids, and ester, which may contribute to its vasorelaxant effect. The results showed that the vasorelaxant activity of SM50 was mostly attributed to channel-linked receptors pathways through the blockage of voltage-operated calcium channels (VOCC). SM50 also acts as both potassium channels opener and inositol triphosphate receptor (IP3R) inhibitor, followed by ß2-adrenergic pathway, and ultimately mediated through the nitric oxide/soluble guanylyl cyclase/cyclic 3',5'-guanosine monophosphate (NO/sGC/cGMP) signaling pathways. The treatment of SM50 also significantly decreased the SBP and DBP in SHRs. In conclusion, the antihypertensive mechanism of SM50 was mediated by VOCC, K+ channels, IP3R, G-protein-coupled ß2-adrenergic receptor, and followed by NO/sGC/cGMP signaling mechanism pathways in descending order. The data suggested that SM50 has the potential to be used as a herbal medicament to treat hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Meliaceae/química , Extratos Vegetais/uso terapêutico , Sementes/química , Vasodilatadores/uso terapêutico , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Aorta Torácica , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Endotélio Vascular/fisiopatologia , Etnofarmacologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Técnicas In Vitro , Malásia , Masculino , Medicina Tradicional , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Músculo Liso Vascular/fisiopatologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Vasodilatadores/química , Vasodilatadores/farmacologia
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