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1.
PLoS One ; 16(1): e0244422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33439902

RESUMO

Here we adapt and evaluate a full-face snorkel mask for use as personal protective equipment (PPE) for health care workers, who lack appropriate alternatives during the COVID-19 crisis in the spring of 2020. The design (referred to as Pneumask) consists of a custom snorkel-specific adapter that couples the snorkel-port of the mask to a rated filter (either a medical-grade ventilator inline filter or an industrial filter). This design has been tested for the sealing capability of the mask, filter performance, CO2 buildup and clinical usability. These tests found the Pneumask capable of forming a seal that exceeds the standards required for half-face respirators or N95 respirators. Filter testing indicates a range of options with varying performance depending on the quality of filter selected, but with typical filter performance exceeding or comparable to the N95 standard. CO2 buildup was found to be roughly equivalent to levels found in half-face elastomeric respirators in literature. Clinical usability tests indicate sufficient visibility and, while speaking is somewhat muffled, this can be addressed via amplification (Bluetooth voice relay to cell phone speakers through an app) in noisy environments. We present guidance on the assembly, usage (donning and doffing) and decontamination protocols. The benefit of the Pneumask as PPE is that it is reusable for longer periods than typical disposable N95 respirators, as the snorkel mask can withstand rigorous decontamination protocols (that are standard to regular elastomeric respirators). With the dire worldwide shortage of PPE for medical personnel, our conclusions on the performance and efficacy of Pneumask as an N95-alternative technology are cautiously optimistic.


Assuntos
Máscaras , Equipamento de Proteção Individual , Recursos Humanos em Hospital , COVID-19/epidemiologia , COVID-19/prevenção & controle , Dióxido de Carbono/química , Desenho de Equipamento , Expiração , Filtração , Humanos , Modelos Teóricos
2.
J Food Sci ; 84(6): 1439-1446, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31106862

RESUMO

The fumigant toxicity of eight individual essential oils (EOs; basil, cinnamon, eucalyptus, mandarin, oregano, peppermint, tea tree, and thyme) and one binary combination (thyme and oregano) for control of the rice weevil, Sitophilus oryzae, were investigated. In bioassays, all individual and combined EOs were toxic to the rice weevil. Eucalyptus EO exhibited the highest toxicity among the individual EO treatments, causing 100% mortality at a minimum concentration of 0.8 µL/mL after 24 hr of exposure. The combination treatment of oregano and thyme EO displayed higher fumigant activity than the individual oregano or thyme treatments. A stable oil-in-water nanoemulsion was evaluated using high-pressure homogenization (microfluidization [MF]) and varying the pressure and number of cycles. The droplet size of the emulsions was found to decrease from 217 to 71 nm and encapsulation efficiency increased from 37% to 84% with increasing MF pressure and number of cycles. The optimum conditions for preparing the mixture of oregano and thyme EO nanoemulsions were evaluated to be homogenization pressure of 103 MPa and three cycles. Incorporating an oregano:thyme nanoemulsion (0.75%) into cellulose nanocrystal (CNC) containing chitosan (CH/CNC), methyl cellulose (MC/CNC), and polylactic acid (PLA/CNC) composite films resulted in extended diffusion matrices causing 32% to 51% rice weevil mortality after 14 days exposure. Irradiation at 200 Gray alone caused 79% mortality and increased to 100% when combined with the bioactive chitosan film containing the oregano:thyme nanoemulsion. PRACTICAL APPLICATION: A binary combination of oregano:thyme has potential as a biopesticide against stored product pests. The encapsulation of EO nanoemulsions into biopolymeric support could be used for bioactive packaging to prevent food spoilage and extend shelf life. Combining bioactive films with irradiation can provide complete control of rice weevil in packaged rice. The system developed in this research may also be extended to explore other food-packaging films with various food models to control different types of stored pests.


Assuntos
Irradiação de Alimentos , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos/métodos , Nanocompostos , Óleos Voláteis/farmacologia , Gorgulhos/efeitos dos fármacos , Animais , Agentes de Controle Biológico , Biopolímeros/química , Quitosana , Cinnamomum zeylanicum , Grão Comestível , Emulsões , Óleo de Eucalipto/farmacologia , Embalagem de Alimentos/métodos , Fumigação , Origanum/química , Controle de Pragas/métodos , Radiação Ionizante , Thymus (Planta)/química , Gorgulhos/efeitos da radiação
3.
Obstet Gynecol ; 133(3): 459-467, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30741812

RESUMO

OBJECTIVE: To compare the effectiveness of cervical pessary to vaginal progesterone for the prevention of preterm birth in women with twin pregnancies and short cervix. METHODS: This randomized controlled trial was conducted at My Duc Hospital, Vietnam. Asymptomatic women with twin pregnancies and cervical length less than 38 mm were randomized to Arabin pessary or vaginal progesterone (400 mg once a day) group. The primary outcome was preterm birth at less than 34 weeks of gestation. Secondary outcomes were adverse maternal and perinatal complications. We planned a subgroup analysis according to quartile of cervical length. Analysis was conducted on an intention-to-treat basis. We estimated that the primary outcome would occur in 28.4% of women treated with progesterone. Thus a total sample size of 290 women divided equally into two groups was required to detect a 14% absolute risk difference in the primary outcome between the two groups (power 80%, alpha-error 5%, 10% loss to follow-up). RESULTS: Between March 2016 and June 2017, we randomized 300 women, 150 women in each group. Preterm birth at less than 34 weeks of gestation occurred in 24 (16%) women in the pessary group and 33 (22%) women in the progesterone group (relative risk [RR] 0.73, 95% CI 0.46-1.18). The use of pessary significantly reduced the composite of poor perinatal outcomes (19% vs 27%; RR 0.70, 95% CI 0.43-0.93). In women with cervical length of 28 mm or less (25th percentile), pessary significantly reduced the preterm birth rate at less than 34 weeks of gestation from 46% (16/35) to 21% (10/47) (RR 0.47, 95% CI 0.24-0.90) and significantly improved the composite of poor perinatal outcomes. CONCLUSION: Cervical pessary and 400 mg vaginal progesterone resulted in similar rates of preterm birth at less than 34 weeks of gestation in women with twin pregnancies and cervical length less than 38 mm. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02623881.


Assuntos
Colo do Útero/anatomia & histologia , Pessários , Nascimento Prematuro/prevenção & controle , Progesterona/uso terapêutico , Progestinas/uso terapêutico , Administração Intravaginal , Adulto , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Terapia Intensiva Neonatal , Análise de Intenção de Tratamento , Pessários/efeitos adversos , Gravidez , Gravidez de Gêmeos , Progesterona/administração & dosagem , Progesterona/efeitos adversos , Progestinas/administração & dosagem , Progestinas/efeitos adversos
4.
Food Microbiol ; 53(Pt B): 24-30, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26678126

RESUMO

The antifungal activities of eight essential oils (EOs) namely basil, cinnamon, eucalyptus, mandarin, oregano, peppermint, tea tree and thyme were evaluated for their ability to inhibit growth of Aspergillus niger, Aspergillus flavus, Aspergillus parasiticus and Penicillium chrysogenum. The antifungal activity of the EOs was assessed by the minimum inhibitory concentration (MIC) using 96-well microplate analysis. The interactions between different EO combinations were done by the checkerboard technique. The highest antifungal activity was exhibited by oregano and thyme which showed lower MIC values amongst all the tested fungi. The antifungal activity of the other EOs could be appropriately ranked in a descending sequence of cinnamon, peppermint, tea tree and basil. Eucalyptus and mandarin showed the least efficiency as they could not inhibit any of the fungal growth at 10,000 ppm. The interaction between these two EOs also showed no interaction on the tested species. A combined formulation of oregano and thyme resulted in a synergistic effect, showing enhanced efficiency against A. flavus and A. parasiticus and P. chrysogenum. Mixtures of peppermint and tea tree produced synergistic effect against A. niger. Application of a modified Gompertz model considering fungal growth parameters like maximum colony diameter, maximum growth rate and lag time periods, under the various EO treatment scenarios, showed that the model could adequately describe and predict the growth of the tested fungi under these conditions.


Assuntos
Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Aspergillus flavus/efeitos dos fármacos , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Origanum/química , Thymus (Planta)/química
5.
Bioorg Med Chem Lett ; 21(18): 5633-7, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21798738

RESUMO

A novel class of pyrazolopyrimidine-sulfonamides was discovered as selective dual inhibitors of aurora kinase A (AKA) and cyclin-dependent kinase 1 (CDK1). These inhibitors were originally designed based on an early lead (compound I). SAR development has led to the discovery of potent inhibitors with single digit nM IC(50)s towards both AKA and CDK1. An exemplary compound 1a has demonstrated good efficacy in an HCT116 colon cancer xenograft model.


Assuntos
Antineoplásicos/farmacologia , Proteína Quinase CDC2/antagonistas & inibidores , Neoplasias do Colo/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Aurora Quinase A , Aurora Quinases , Proteína Quinase CDC2/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Neoplasias do Colo/patologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Desenho de Fármacos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Pirimidinas/síntese química , Pirimidinas/química , Estereoisomerismo , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Bioorg Med Chem Lett ; 19(11): 3128-35, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19398333

RESUMO

Chloro-oxime derivatives were investigated as novel small molecule chaperone amplifiers. Lead optimization led to the discovery of compounds that displayed potent HSF1 activation activity, significant cytoprotection in MG-132 stress, ER stress and PolyQ stress cell models (EC(50)<10 microM).


Assuntos
Chaperonas Moleculares/química , Oximas/química , Linhagem Celular Tumoral , Citoproteção , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição de Choque Térmico , Humanos , Chaperonas Moleculares/metabolismo , Oximas/síntese química , Oximas/farmacologia , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
7.
Neurosci Lett ; 449(3): 224-7, 2009 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-19010389

RESUMO

Metabotropic glutamate receptors (mGluRs) are densely expressed in the limbic system of the mammalian brain. Increasing evidence suggests a critical role of mGluRs in the pathogenesis of various mental illnesses, including drug abuse and addiction. In this study, we investigated the effect of psychostimulant, cocaine, on protein expression of a specific mGluR subtype, mGluR8, in the rat forebrain in vivo. A rabbit antibody against the extracellular N-terminus of mGluR8 was developed to detect changes in mGluR8 proteins in immunoblot assays. With this antibody, we found that acute systemic injection of cocaine reduced mGluR8 protein levels in the striatum. The reduction of mGluR8 proteins was rapid and transient as it was induced 25min after cocaine injection and returned to the normal level by 6h. No significant change in mGluR8 protein levels in the prefrontal cortex and the hippocampus was observed following cocaine administration. These data demonstrate that protein expression of mGluR8 is subject to the modulation by dopamine stimulation. Acute exposure to cocaine results in a dynamic and region-specific downregulation of mGluR8 expression in the striatum.


Assuntos
Cocaína/administração & dosagem , Corpo Estriado/efeitos dos fármacos , Inibidores da Captação de Dopamina/administração & dosagem , Receptores de Glutamato Metabotrópico/metabolismo , Animais , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
8.
J Med Chem ; 49(17): 5352-62, 2006 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-16913725

RESUMO

We report on the discovery of benzo- and pyridino- thiazolothiopurines as potent heat shock protein 90 inhibitors. The benzothiazole moiety is exceptionally sensitive to substitutions on the aromatic ring with a 7'-substituent essential for activity. Some of these compounds exhibit low nanomolar inhibition activity in a Her-2 degradation assay (28-150 nM), good aqueous solubility, and oral bioavailability profiles in mice. In vivo efficacy experiments demonstrate that compounds of this class inhibit tumor growth in an N87 human colon cancer xenograft model via oral administration as shown with compound 37 (8-(7-chlorobenzothiazol-2-ylsulfanyl)-9-(2-cyclopropylamino-ethyl)-9H- purin-6-ylamine).


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Purinas/farmacologia , Compostos de Sulfidrila/química , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Purinas/administração & dosagem , Purinas/química , Estereoisomerismo , Relação Estrutura-Atividade , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
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