Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
1.
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.

2.
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.

3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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.

10.
Nutrients ; 10(8)2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30096951

RESUMO

The growth of adipose tissues is considered angiogenesis-dependent during non-alcoholic fatty liver disease (NAFLD). We have recently reported that our standardized 50% methanolic extract (ME) of Phyllanthus niruri (50% ME of P. niruri) has alleviated NAFLD in Sprague⁻Dawley rats. This study aimed to assess the molecular mechanisms of action, and to further evaluate the antiangiogenic effect of this extract. NAFLD was induced by eight weeks of high-fat diet, and treatment was applied for four weeks. Antiangiogenic activity was assessed by aortic ring assay and by in vitro tests. Our findings demonstrated that the therapeutic effects of 50% ME among NAFLD rats, were associated with a significant increase in serum adiponectin, reduction in the serum levels of RBP4, vaspin, progranulin, TNF-α, IL-6, and significant downregulation of the hepatic gene expression of PPARγ, SLC10A2, and Collα1. Concomitantly, 50% ME of P. niruri has exhibited a potent antiangiogenic activity on ring assay, cell migration, vascular endothelial growth factor (VEGF), and tube formation, without any cytotoxic effect. Together, our findings revealed that the protective effects of P. niruri against NAFLD might be attributed to its antiangiogenic effect, as well as to the regulation of adipocytokines and reducing the expression of adipogenic genes.


Assuntos
Adipocinas/metabolismo , Inibidores da Angiogênese/farmacologia , Proteínas Angiogênicas/metabolismo , Fígado/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Phyllanthus , Extratos Vegetais/farmacologia , Adipocinas/genética , Inibidores da Angiogênese/isolamento & purificação , Proteínas Angiogênicas/genética , Animais , Linhagem Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Phyllanthus/química , Extratos Vegetais/isolamento & purificação , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
11.
Nanomaterials (Basel) ; 8(2)2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29462883

RESUMO

Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.

12.
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
13.
Biomed Pharmacother ; 97: 985-994, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29136777

RESUMO

Although Banxia Baizhu Tianma Tang (BBT) has been long administered for hypertensive treatment in Traditional Chinese Medicine (TCM), the ratio of the herbal components that makes up the formulation has not been optimized with respect to the anti-hypertensive effect that it inherently possesses. A newly amended BBT (ABBT) formulation was developed using the evidence-based approach of orthogonal stimulus-response compatibility model. The ABBT showed enhanced therapeutic effect while maintaining its traditional theoretical approach rooted in TCM. This study was designed to investigate the possible mechanism of actions involved in the vasodilatory activity of ABBT-50 by evaluating its vasodilative effect on isolated Sprague Dawley rats in the presence of absence of various antagonists. When pre-contracted with phenylephrine, relaxation was observed in endothelium intact (EC50=0.027±0.003mg/ml, Rmax=109.8±2.12%) and denuded aortic rings (EC50=0.409±0.073mg/ml, Rmax=63.15±1.78%), as well as in endothelium intact aortic rings pre-contracted with potassium chloride (EC50=32.7±12.16mg/ml, Rmax=34.02±3.82%). Significant decrease in the vasodilative effect of ABBT-50 was observed in the presence of Nω-nitro-l-arginine methyl ester (EC50=0.12±0.021mg/ml, Rmax=75.33±3.28%), 1H-[1,2,4] Oxadiazolo[4,3-a]quinoxalin-1-one (EC50=0.463±0.18mg/ml, Rmax=54.48±2.02%), methylene blue (EC50=0.19±0.037mg/ml, Rmax=83.69±3.19%), indomethacin (EC50=0.313±0.046mg/ml, Rmax=71.33±4.12%), atropine (EC50=0.146±0.013mg/ml, Rmax=77.2±3.41%), and 4-aminopyridine (EC50=0.045±0.008mg/ml, Rmax=95.55±2.36%). ABBT-50 was also suppressing Ca2+ release from sarcoplasmic reticulum and inhibiting calcium channels. Vasodilatory effects of ABBT-50 are mediated through NO/sGC/cGMP cascade and PGI2, followed by muscarinic pathways and calcium channels.


Assuntos
Anti-Hipertensivos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , GMP Cíclico/metabolismo , Endotélio Vascular/efeitos dos fármacos , Masculino , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo
14.
J Med Food ; 20(12): 1201-1213, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28953423

RESUMO

Hypertension, one of the famous "silent killers" that can attack people at any age, is a current hot topic among scientists due to multiple syndromic behavior and concomitant diseases. The new scientific-based Traditional Chinese Medicine (TCM) formulation approach was used in a previous study by combining five TCM herbs, including Gastrodia elata Bl., Uncaria rhynchophylla (Miq.) Miq. ex Havil., Pueraria thomsonii Benth., Panax notoginseng (Burk.) F.H. Chen, and Alisma orientalis (Sam.) Juzep in optimized ratio (named BPAid). The objective of the present study was to evaluate the mechanism pathways employed by BPAid for vasodilatory effect with the use of an in vitro isolated aortic rings assay. Interestingly, all the mechanisms investigated were involved in the BPAid's vasodilation activity in which the majority contributed through the nitric oxide/soluble guanylyl cyclase/cyclic guanosine monophosphate (NO/sGC/cGMP) pathways, followed by prostacyclin (PGI2), ß2-adrenergic, and M3-receptors pathways. Furthermore, the BPAid appeared to manage vascular tone by regulating action potential through potassium and both voltage-operated calcium channel and inositol triphosphate receptor (IP3R) pathways. The results obtained has confirmed the expected outcome that the benefits of TCM herbs in BPAid can meet the criteria of counteracting multiple signaling mechanism pathways involved in the etiology of hypertension. In addition to this study, the fingerprints and chemical properties of BPAid was identified by using tri-step Fourier transform infrared spectroscopy and compared with its derivatives. The results obtained suggested that the majority of the vasodilatory effects exerted by BPAid were attributed to the presence of saponins and aromatic ring-containing vasoactive compounds.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Hipertensão/tratamento farmacológico , Vasodilatadores/administração & dosagem , Animais , Canais de Cálcio/metabolismo , Medicamentos de Ervas Chinesas/química , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos , Vasodilatadores/química
15.
J Med Food ; 20(9): 895-911, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28771084

RESUMO

Uncaria rhynchophylla is one of the major components included in Traditional Chinese Medicine prescriptions for hypertensive treatment. Previous studies have suggested that U. rhynchophylla might contain vasodilation-mediating active compounds, especially indole alkaloids. Hence, this study was carried out to determine the vasodilatory effects of U. rhynchophylla, which was extracted by different solvents. The most effective extract was then further studied for its signaling mechanism pathways. The authenticity of U. rhynchophylla was assured by using modernized tri-step Fourier transform infrared (FTIR), including conventional 1D FTIR, second derivative scanning combined with 2D-correlated IR spectroscopy. Results obtained proved that the fingerprint of U. rhynchophylla used was identical to the atlas. Isolated aortic rings from male Sprague-Dawley rats were preconstricted with phenylephrine (PE) followed by cumulative addition of U. rhynchophylla extracts. The signaling mechanism pathways were studied by incubation with different receptor antagonists before the PE precontraction. In conclusion, the 95% ethanolic U. rhynchophylla extract (GT100) was found to be most effective with an EC50 value of 0.028 ± 0.002 mg/mL and an Rmax value of 101.30% ± 2.82%. The signaling mechanism pathways employed for exerting its vasodilatory effects included nitric oxide/soluble guanylyl cylcase/cyclic guanosine monophosphate (NO/sGC/cGMP) and PGI2 (endothelium-derived relaxing factors), G protein-coupled M3- and ß2 receptors, regulation of membrane potential through voltage-operated calcium channel, intracellular Ca2+ released from inositol triphosphate receptor (IP3R), and all potassium channels except the Kca channel.


Assuntos
Hipertensão/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Uncaria/química , Vasodilatadores/administração & dosagem , Animais , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
16.
Nutrients ; 9(9)2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28832548

RESUMO

BACKGROUND: An aqueous extract (AE) of vinegar made from Nypa fruticans Wurmb. can improve postprandial glucose levels in normoglycaemic rats. The aim of this study was to evaluate its antihyperglycaemic activity further using in vivo and in vitro approaches. METHODS: AE was administered to streptozotocin (STZ)-induced diabetic rats twice daily at three doses (1000, 500, and 250 mg/kg b.w.) for 12 days p.o. Several biochemical analyses and a histological study of the pancreas and liver were performed, accompanied by a cell culture assay. RESULTS: As compared to diabetic control (DC), AE at the doses of 500 and 1000 mg/kg b.w. caused significant reduction (p < 0.05) of blood glucose, total cholesterol and triglycerides levels, with positive improvement of serum insulin levels. Interestingly, immunohistochemical staining of the pancreas suggested no ß-cell regeneration, despite significant increase in insulin production. AE-treated groups, however, showed overall restoration of the hepatic histoarchitecture of STZ-induced liver damage, suggesting a possible hepatoprotective effect. The pancreatic effect of AE was further studied through RIN-5F cell culture, which revealed a positive stimulatory effect on insulin release at a basal glucose concentration (1.1 mM). CONCLUSION: Nypa fruticans Wurmb. vinegar's aqueous extract exerts its antihyperglycaemic activity, at least in part, through insulin stimulatory and hepatoprotective effects.


Assuntos
Arecaceae , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/sangue , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Arecaceae/química , Biomarcadores/sangue , Glicemia/metabolismo , Linhagem Celular Tumoral , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Hipoglicemiantes/isolamento & purificação , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Lipídeos/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Ratos Sprague-Dawley , Estreptozocina
17.
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
18.
Nutrients ; 9(7)2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28718838

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is one of the major global health issues, strongly correlated with insulin resistance, obesity and oxidative stress. The current study aimed to evaluate anti-NAFLD effects of three different extracts of Phyllanthus niruri (P. niruri). NAFLD was induced in male Sprague-Dawley rats using a special high-fat diet (HFD). A 50% methanolic extract (50% ME) exhibited the highest inhibitory effect against NAFLD progression. It significantly reduced hepatomegaly (16%) and visceral fat weight (22%), decreased NAFLD score, prevented fibrosis, and reduced serum total cholesterol (TC) (48%), low-density lipoprotein (LDL) (65%), free fatty acids (FFAs) (25%), alanine aminotransferase (ALT) (45%), alkaline phosphatase (ALP) (38%), insulin concentration (67%), homeostatic model assessment of insulin resistance (HOMA-IR) (73%), serum atherogenic ratios TC/high-density lipoprotein (HDL) (29%), LDL/HDL (66%) and (TC-HDL)/HDL (64%), hepatic content of cholesterol (43%), triglyceride (29%) and malondialdehyde (MDA) (40%) compared to a non-treated HFD group. In vitro, 50% ME of P. niruri inhibited α-glucosidase, pancreatic lipase enzymes and cholesterol micellization. It also had higher total phenolic and total flavonoid contents compared to other extracts. Ellagic acid and phyllanthin were identified as major compounds. These results suggest that P. niruri could be further developed as a novel natural hepatoprotective agent against NAFLD and atherosclerosis.


Assuntos
Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Phyllanthus/química , Extratos Vegetais/farmacologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/sangue , Resistência à Insulina , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue , alfa-Glucosidases/metabolismo
19.
J AAPOS ; 21(3): 249-251, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28532706

RESUMO

Blau syndrome is an early-onset granulomatous disease known to affect the skin, joints, and eyes. We report a child with diffuse rash, arthritis, and subconjunctival nodules. Biopsy of the bulbar conjunctiva revealed noncaseating lipogranulomas that lead to a diagnosis of Blau syndrome. To our knowledge, noncaseating lipogranulomas of the conjunctiva have not been reported previously as a presenting finding in Blau syndrome. Although uveitis is the classic manifestation, it is important to broaden the awareness of other ocular signs, as these variations can aid in diagnosis.


Assuntos
Artrite/diagnóstico , Doenças da Túnica Conjuntiva/diagnóstico , Lipogranulomatose de Farber/diagnóstico , Sinovite/diagnóstico , Uveíte/diagnóstico , Artrite/tratamento farmacológico , Artrite/genética , Doenças da Túnica Conjuntiva/tratamento farmacológico , Doenças da Túnica Conjuntiva/genética , Lipogranulomatose de Farber/tratamento farmacológico , Lipogranulomatose de Farber/genética , Fluormetolona/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Lactente , Masculino , Mutação , Proteína Adaptadora de Sinalização NOD2/genética , Sarcoidose , Sinovite/tratamento farmacológico , Sinovite/genética , Uveíte/tratamento farmacológico , Uveíte/genética , Sequenciamento do Exoma
20.
J AAPOS ; 21(3): 215-218, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28450179

RESUMO

PURPOSE: To investigate the indications for and results of amniotic membrane transplantation (AMT) for the treatment of ocular disease in pediatric patients at a single institution. METHODS: The medical records of patients <18 years of age who underwent AMT for ocular disease between January 1, 2003, and September 1, 2015, were reviewed retrospectively. Patients were determined to have reached a clinical endpoint if there was resolution of the ocular condition being treated after AMT placement, no additional surgery required for treatment of the ocular condition, and no active disease at most recent follow-up. RESULTS: A total of 48 records were reviewed. Of these, 32 patients (67%) received AMT for treatment of ocular disease related to Stevens Johnson syndrome (SJS), 29 (94%) of whom reached the clinical endpoint. The remaining 16 patients (33%) underwent AMT for indications other than SJS, including difficult-to-treat corneal epithelial defects and ulcers, conjunctival reconstruction, and scarring after strabismus surgery. Of these, 80% reached the clinical endpoint. There were no adverse effects related to AMT in either group. CONCLUSIONS: In our series, AMT was used successfully and without complications.


Assuntos
Âmnio/transplante , Cicatriz/cirurgia , Doenças da Túnica Conjuntiva/cirurgia , Doenças da Córnea/cirurgia , Síndrome de Stevens-Johnson/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA