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1.
Molecules ; 25(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202707

RESUMO

Recently, tissue engineering and regenerative medicine studies have evaluated smart biomaterials as implantable scaffolds and their interaction with cells for biomedical applications. Porous materials have been used in tissue engineering as synthetic extracellular matrices, promoting the attachment and migration of host cells to induce the in vitro regeneration of different tissues. Biomimetic 3D scaffold systems allow control over biophysical and biochemical cues, modulating the extracellular environment through mechanical, electrical, and biochemical stimulation of cells, driving their molecular reprogramming. In this review, first we outline the main advantages of using polysaccharides as raw materials for porous scaffolds, as well as the most common processing pathways to obtain the adequate textural properties, allowing the integration and attachment of cells. The second approach focuses on the tunable characteristics of the synthetic matrix, emphasizing the effect of their mechanical properties and the modification with conducting polymers in the cell response. The use and influence of polysaccharide-based porous materials as drug delivery systems for biochemical stimulation of cells is also described. Overall, engineered biomaterials are proposed as an effective strategy to improve in vitro tissue regeneration and future research directions of modified polysaccharide-based materials in the biomedical field are suggested.

2.
Medwave ; 20(9): e8041, 2020 Oct 01.
Artigo em Espanhol | MEDLINE | ID: mdl-33031357

RESUMO

Introduction: Healthcare systems are developed in imperfect scenarios, in which there are constant failures (uncertainty, information asymmetry, agency relationship problem, and supply-induced demand). These failures, based on the imperfection of the sector, determine the relationships and incentives between the actors. It is within this context that payment mechanisms regulate aspects of the system behavior and incentives, acting as instruments for the purchasing of health care from providers, mediated by health insurance on behalf of users. Objective: To characterize the basic elements of most frequent payment mechanisms to help providers in their relationship with payers. Methods: A review of the evidence was conducted in PubMed, Google, Google Scholar, and strategic snowball selection. Payment mechanisms consist of three classical microeconomics variables, fixed or variable: price, quantity, and expense. Time dimensions are used to analyze their attributes and effects. Different mechanisms emerge from the combination of these variables. Results: Among the most used are: Fee-For-Service, Global Budget, Bundled Payments, Diagnosis-Related Groups, Per-capita, Performance Pay, and Risk-Sharing Agreements. A fourth has also gained importance: Financial Risk. Conclusions: Payment mechanisms are essential to link health efforts with clinical practice. They make it possible to regulate relationships between insurers, providers, and users, which, depending on the architecture of the mechanism, can become beneficial or hinder the fulfillment of the objectives of the health system.

3.
Medwave ; 20(9)30-10-2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1140190

RESUMO

Introducción Los sistemas de salud se desarrollan en ámbitos complejos y con fallas constantes (incertidumbre, asimetría de información, problema de relación de agencia e inducción de demanda). Estas fallas determinan las relaciones e incentivos entre los actores y se basan en la imperfección del sector. Frente a ello, los mecanismos de pago regulan aspectos del comportamiento e incentivos del sistema, participando como instrumentos de compra de atenciones de salud a prestadores, mediados por los seguros de salud en representación de los usuarios. Objetivo Caracterizar los elementos básicos de las tipologías más frecuentes de los mecanismos de pago con el propósito de para apoyar la labor de los prestadores en su relación con pagadores. Métodos Se condujo una revisión dirigida de la evidencia en PubMed, Google, Google Scholar y selección estratégica en bola de nieve. Los mecanismos de pago están conformados por tres variables microeconómicas clásicas fijas o variables: precio, cantidad y gasto; y dimensiones temporales utilizadas para analizar sus atributos y efectos. De la combinación de estas variables surgen distintos mecanismos. Resultados Entre los más utilizados se describen: pago por servicio, presupuesto global, Bundled Payments, grupos relacionados de diagnóstico, per cápita, pago por desempeño y acuerdos de riesgo compartido. Dentro de sus variables ha cobrado importancia una cuarta, el riesgo financiero. Conclusiones Los mecanismos de pago resultan esenciales para concatenar esfuerzos sanitarios con la práctica clínica. Permiten regular relaciones entre seguros, prestadores y usuarios. Dependiendo de la arquitectura del mecanismo, estas pueden tornarse beneficiosas o entorpecer el cumplimiento de los objetivos del sistema sanitario.


Introduction Healthcare systems are developed in imperfect scenarios, in which there are constant failures (uncertainty, information asymmetry, agency relationship problem, and supply-induced demand). These failures, based on the imperfection of the sector, determine the relationships and incentives between the actors. It is within this context that payment mechanisms regulate aspects of the system behavior and incentives, acting as instruments for the purchasing of health care from providers, mediated by health insurance on behalf of users. Objective To characterize the basic elements of most frequent payment mechanisms to help providers in their relationship with payers. Methods A review of the evidence was conducted in PubMed, Google, Google Scholar, and strategic snowball selection. Payment mechanisms consist of three classical microeconomics variables, fixed or variable: price, quantity, and expense. Time dimensions are used to analyze their attributes and effects. Different mechanisms emerge from the combination of these variables. Results Among the most used are: Fee-For-Service, Global Budget, Bundled Payments, Diagnosis-Related Groups, Per-capita, Performance Pay, and Risk-Sharing Agreements. A fourth has also gained importance: Financial Risk. Conclusions Payment mechanisms are essential to link health efforts with clinical practice. They make it possible to regulate relationships between insurers, providers, and users, which, depending on the architecture of the mechanism, can become beneficial or hinder the fulfillment of the objectives of the health system.

4.
Molecules ; 25(9)2020 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-32375224

RESUMO

Smart conductive materials are developed in regenerative medicine to promote a controlled release profile of charged bioactive agents in the vicinity of implants. The incorporation and the active electrochemical release of the charged compounds into the organic conductive coating is achieved due to its intrinsic electrical properties. The anti-inflammatory drug dexamethasone was added during the polymerization, and its subsequent release at therapeutic doses was reached by electrical stimulation. In this work, a Poly (3,4-ethylenedioxythiophene): κ-carrageenan: dexamethasone film was prepared, and κ-carrageenan was incorporated to keep the electrochemical and physical stability of the electroactive matrix. The presence of κ-carrageenan and dexamethasone in the conductive film was confirmed by µ-Raman spectroscopy and their effect in the topographic was studied using profilometry. The dexamethasone release process was evaluated by cyclic voltammetry and High-Resolution mass spectrometry. In conclusion, κ-carrageenan as a doping agent improves the electrical properties of the conductive layer allowing the release of dexamethasone at therapeutic levels by electrochemical stimulation, providing a stable system to be used in organic bioelectronics systems.

5.
Medwave ; 20(4): e7910, 2020 05 27.
Artigo em Espanhol | MEDLINE | ID: mdl-32469852

RESUMO

Introduction: Payment mechanisms serve to put into operation the function of purchasing in health. Payment mechanisms impact the decisions that healthcare providers make. Given this, we are interested in knowing how they affect the generalized increase of C-section rates globally. Objective: The objective of this review is to describe existing payment mechanisms for childbirth in countries members of the Organization for Economic Co-operation and Development (OECD) and non-members. Methods: We conducted a scoping review following the five methodological steps of the Joanna Briggs Institute. The search was conducted by researchers independently, achieving inter-reliability among raters (kappa index, 0.96). We searched electronic databases, grey literature, and governmental and non-governmental websites. We screened on three levels and included documents published in the last ten years, in English and Spanish. Results were analyzed considering the function of the reimbursement mechanism and its effects on providers, payers, and beneficiaries. Results: Evidence from 34 countries was obtained (50% OECD members). Sixty-four percent of countries report the use of more than one payment mechanism for childbirth. Diagnosis-Related Groups (47.6%), Pay-for-performance (23.3%), Fee-for-service (16.6%) and Fixed-prospective systems (13.3%) are among the most frequently used mechanisms. Conclusion: Countries use payment mechanism architecture to improve maternal-perinatal health indicators. Therefore, it is necessary to explore the best combination of mechanisms that improve the provision of health care and welfare of the population in the field of sexual and reproductive health.

6.
Medwave ; 20(4)30 de mayo de 2020.
Artigo em Inglês, Espanhol | LILACS-Express | LILACS | ID: biblio-1103968

RESUMO

Introducción Los mecanismos de pago corresponden a la operacionalización de la función de compra en salud, incentivando comportamientos en los proveedores de servicios sanitarios. Resulta pertinente preguntarse cómo afectan la vía de resolución del parto, considerando el aumento generalizado en índices de cesárea a nivel global. Objetivo Describir los mecanismos de pago existentes para la atención del parto en países miembros y no miembros de la Organización para la Cooperación y el Desarrollo Económico. Métodos Revisión sistemática exploratoria (scoping review). Se adoptaron los cinco pasos metodológicos del Joanna Briggs Institute. La búsqueda se realizó por las investigadoras de forma independiente, logrando la confiabilidad interevaluador (κ 0,96) en bases de datos electrónicas, otras fuentes de información, sitios web gubernamentales y no gubernamentales. Se tamizó en tres niveles, considerando literatura no mayor a 10 años de anti-güedad, idioma inglés y español. Se analizaron los resultados considerando el funcionamiento del mecanismo de pago y sus efectos en prestado-res, seguros y beneficiarias. Resultados Se obtuvo evidencia de 34 países (50% pertenecientes a la Organización para la Cooperación y el Desarrollo Económico). El 64% con uso de más de un mecanismo de pago para el parto. Entre los mecanismos más utilizados están: grupos relacionados de diagnósticos (47,6%), pago por resultados (23,3%), pago por servicios (16,6%) y pago fijo prospectivo (13,3%). Conclusión Los países recurren a la arquitectura de los mecanismos de pago para mejorar indicadores en salud materno-perinatales. Es necesario explorar cuál sería la mejor combinación de mecanismos que mejora la provisión de atenciones de salud y bienestar de la población, en el campo de la salud sexual y reproductiva.


Introduction Payment mechanisms serve to put into operation the function of purchasing in health. Payment mechanisms impact the decisions that healthcare providers make. Given this, we are interested in knowing how they affect the generalized increase of C-section rates globally. Objective The objective of this review is to describe existing payment mechanisms for childbirth in countries members of the Organization for Economic Co-operation and Development (OECD) and non-members. Methods We conducted a scoping review following the five methodological steps of the Joanna Briggs Institute. The search was conducted by researchers independently, achieving inter-reliability among raters (kappa index, 0.96). We searched electronic databases, grey literature, and governmental and non-governmental websites. We screened on three levels and included documents published in the last ten years, in English and Spanish. Results were analyzed considering the function of the reimbursement mechanism and its effects on providers, payers, and beneficiaries. Results Evidence from 34 countries was obtained (50% OECD members). Sixty-four percent of countries report the use of more than one payment mechanism for childbirth. Diagnosis-Related Groups (47.6%), Pay-for-performance (23.3%), Fee-for-service (16.6%) and Fixed-prospective systems (13.3%) are among the most frequently used mechanisms. Conclusion Countries use payment mechanism architecture to improve maternal-perinatal health indicators. Therefore, it is necessary to explore the best combination of mechanisms that improve the provision of health care and welfare of the population in the field of sexual and reproductive health.

7.
Educ. med. super ; 34(1): e1727, ene.-mar. 2020. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1124656

RESUMO

RESUMEN Introducción: La determinación de la calidad de un instrumento de medición implica la evaluación tanto de la exactitud como de la estabilidad de dicha medición o el resultado. Objetivo: Evaluar el índice de dificultad y discriminación de los ítems de los instrumentos de medición de algunas asignaturas del eje curricular de Fundamentos de la medicina de una escuela de medicina particular. Métodos: Mediante estudio observacional, comparativo, transversal y prolectivo, se analizaron los ítems del examen ordinario de las asignaturas Morfología, Bioquímica y Biología Molecular, y Microbiología y Virología Médica, los cuales fueron contestados por 112 alumnos de Morfología, 101 de Bioquímica y Biología Molecular y 89 de Microbiología y Virología Médica. El número de reactivos resultó 100 para Morfología, 80 para Bioquímica y Biología Molecular y 75 para Microbiología y Virología Médica. Se utilizó estadística descriptiva, y se calculó el índice de dificultad y el índice de discriminación de los ítems y de todo el examen. Además, se utilizó ANOVA, considerando estadísticamente significativo un resultado igual o menor a 0,05. Resultados: Los ítems resultaron más difíciles en el examen de Morfología, ya que el 19 % correspondió a la clasificación de relativamente difíciles y el 50 % a la de difíciles, con un total del 69 % entre relativamente difíciles y difíciles. El índice de discriminación resultó mayor en la asignatura de Microbiología y Virología Médica, mientras que en Bioquímica y Biología Molecular se presentó una buena capacidad de discriminación. Conclusiones: Existió variabilidad en el grado de dificultad y el poder de discriminación de los ítems de los exámenes analizados.


ABSTRACT Introduction: Determining the quality of a measuring instrument implies the evaluation of both the accuracy and the stability of such measurement or result. Objective: To evaluate the index of difficulty and discrimination of the items of the measuring instruments of some subjects of the curricular axis of Fundamentals of Medicine of a particular medical school. Methods: By means of an observational, comparative, cross-sectional and prolective study, the items of the ordinary examination of the subjects Morphology, Biochemistry and Molecular Biology, and Microbiology and Medical Virology were analyzed, which were answered by 112 students of Morphology, 101 of Biochemistry and Biology Molecular, and 89 of Microbiology and Medical Virology. The number of reagents was 100 for Morphology, 80 for Biochemistry and Molecular Biology, and 75 for Microbiology and Medical Virology. Descriptive statistics were used, and the difficulty index and the discrimination index of the items and of the entire exam were calculated. In addition, ANOVA was used, considering a statistically significant result equal to or less than 0.05. Results: The items were more difficult in the Morphology test, since 19% corresponded to the classification of relatively difficulty and 50% corresponded to those of difficulty, with a total of 69% between relative difficulty and difficulty. The discrimination index was higher in the subject of Microbiology and Medical Virology, while in Biochemistry and Molecular Biology there was a good capacity for discrimination. Conclusions: There was variability in the degree of difficulty and the power of discrimination of the items of the analyzed exams.

8.
Int J Parasitol Parasites Wildl ; 11: 88-92, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31956482

RESUMO

Haemosporidian parasites of birds are found worldwide and include the genera Haemoproteus, Plasmodium and Leucocytozoon. Infection with haemosporidian parasites can affect host physical condition and reproductive success. The aim of this study was to identify the blood parasites and parasitaemia in endemic and non-endemic passerine birds from central Mexico highlands. This study included 157 passerines representing 29 species from 17 families. Overall, 30.6% (48/157) of the birds were infected with blood parasites. Of those, Haemoproteus spp. were found in 14.0% (n = 22), Leucocytozoon spp. 12.1% (n = 19) and microfilariae 0.6% (n = 1). Blood parasites were found in 71.4% (5/7) of endemic bird species and 45.4% (10/22) of non-endemic species. Medium to high parasitaemia (number of parasites/number erythrocytes) was observed in birds with infections of Haemoproteus spp. and Leucocytozoon spp. Co-infections 3.8% (n = 6) were observed in two species of endemic birds. This study contributes to the knowledge of haemoparasites in endemic and non-endemic passerine birds from central Mexico highlands. Additional investigation on the molecular identification of haemosporidian parasites, pathogenicity and health status of these birds is necessary.

9.
Braz J Microbiol ; 49 Suppl 1: 269-275, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30145263

RESUMO

Fusarium oxysporum f. sp. lycopersici is a phytopathogenic fungus that causes vascular wilt in tomato plants. In this work we analyze the influence of metal salts such as iron and copper sulphate, as well as that of bathophenanthrolinedisulfonic acid (iron chelator) and bathocuproinedisulfonic acid (copper chelator) on the activity of laccases in the intra (IF) and extracellular fractions (EF) of the wild-type and the non-pathogenic mutant strain (rho1::hyg) of F. oxysporum. The results show that laccase activity in the IF fraction of the wild and mutant strain increased with the addition of iron chelator (53.4 and 114.32%; respectively). With copper, it is observed that there is an inhibition of the activity with the addition of CuSO4 for the EF of the wild and mutant strain (reduction of 82 and 62.6%; respectively) and for the IF of the mutant strain (54.8%). With the copper chelator a less laccase activity in the IF of the mutant strain was observed (reduction of 53.9%). The results obtained suggest a different regulation of intracellular laccases in the mutant strain compared with the wild type in presence of CuSO4 and copper chelator which may be due to the mutation in the rho gene.


Assuntos
Cobre/metabolismo , Proteínas Fúngicas/metabolismo , Fusarium/enzimologia , Ferro/metabolismo , Lacase/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Fusarium/química , Fusarium/genética , Lacase/química , Lacase/genética , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia
10.
Can J Cardiol ; 34(7): 850-862, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29960614

RESUMO

Worldwide, more than 230 million adults have major noncardiac surgery each year. Although surgery can improve quality and duration of life, it can also precipitate major complications. Moreover, a substantial proportion of deaths occur after discharge. Current systems for monitoring patients postoperatively, on surgical wards and after transition to home, are inadequate. On the surgical ward, vital signs evaluation usually occurs only every 4-8 hours. Reduced in-hospital ward monitoring, followed by no vital signs monitoring at home, leads to thousands of cases of undetected/delayed detection of hemodynamic compromise. In this article we review work to date on postoperative remote automated monitoring on surgical wards and strategy for advancing this field. Key considerations for overcoming current barriers to implementing remote automated monitoring in Canada are also presented.


Assuntos
Monitorização Fisiológica/métodos , Cuidados Pós-Operatórios/métodos , Procedimentos Cirúrgicos Operatórios , Telemedicina/métodos , Sinais Vitais/fisiologia , Humanos
11.
Cardiol Young ; 28(7): 903-909, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29759095

RESUMO

IntroductionIntracardiac rhabdomyomas can cause severe ventricular dysfunction and outflow tract obstruction.Case reportA term newborn infant with antenatal diagnosis of giant left ventricle rhabdomyoma presented with cardiac failure and duct-dependent systemic circulation after birth. She was treated successfully with everolimus, showing decrease in tumour size and improvement in left ventricular ejection fraction.DiscussionTumour regression rate was 0.32 cm2/day and improved to 0.80 cm2/day with the use of everolimus. Herein we report a newborn with inoperable giant left ventricular cardiac rhabdomyoma and significant regression of the tumour. To our knowledge, this is the largest left ventricular rhabdomyoma reported. A review of the literature was undertaken for comparison. CONCLUSION: Everolimus has proven to be efficacious in size reduction of cardiac rhabdomyomas in cases when surgical resection is not possible.


Assuntos
Antineoplásicos/uso terapêutico , Everolimo/uso terapêutico , Neoplasias Cardíacas/tratamento farmacológico , Rabdomioma/tratamento farmacológico , Ecocardiografia , Feminino , Insuficiência Cardíaca/etiologia , Neoplasias Cardíacas/diagnóstico por imagem , Ventrículos do Coração/efeitos dos fármacos , Humanos , Recém-Nascido , Gravidez , Diagnóstico Pré-Natal , Rabdomioma/diagnóstico por imagem , Resultado do Tratamento
12.
J Vis Exp ; (134)2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29757267

RESUMO

Bis-phenols, such as bis-phenol A (BPA) and bis-phenol-S (BPS), are polymerizing agents widely used in the production of plastics and numerous everyday products. They are classified as endocrine disrupting compounds (EDC) with estradiol-like properties. Long-term exposure to EDCs, even at low doses, has been linked with various health defects including cancer, behavioral disorders, and infertility, with greater vulnerability during early developmental periods. To study the effects of BPA on the development of neuronal function, we used an in vitro neuronal network derived from the early chick embryonic brain as a model. We found that exposure to BPA affected the development of network activity, specifically spiking activity and synchronization. A change in network activity is the crucial link between the molecular target of a drug or compound and its effect on behavioral outcome. Multi-electrode arrays are increasingly becoming useful tools to study the effects of drugs on network activity in vitro. There are several systems available in the market and, although there are variations in the number of electrodes, the type and quality of the electrode array and the analysis software, the basic underlying principles, and the data obtained is the same across the different systems. Although currently limited to analysis of two-dimensional in vitro cultures, these MEA systems are being improved to enable in vivo network activity in brain slices. Here, we provide a detailed protocol for embryonic exposure and recording neuronal network activity and synchrony, along with representative results.


Assuntos
Eletrodos/estatística & dados numéricos , Disruptores Endócrinos/química , Neurônios/metabolismo , Vertebrados/crescimento & desenvolvimento , Animais , Embrião de Galinha , Humanos
13.
J Ethnopharmacol ; 222: 159-164, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29704591

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bidens odorata Cavanilles is a medicinal and edible plant known as "mozote blanco, aceitilla, acahual, mozoquelite" which is traditionally used in Mexico as a diuretic, hypoglycaemic, anti-inflammatory, antipyretic, antitussive, to treat gastrointestinal disorders, kidney pain, and lung or respiratory diseases. AIM OF THE STUDY: This research study was aimed at phytochemical analysis of aerial extracts of B. odorata for antimycobacterial and lipid-lowering activities. MATERIALS AND METHODS: Compounds 1 (((2R, 3R, 4S, 5S, 6R)-3,4,5-Tryhidroxy-6-(((E)-3-(4-hydroxyphenyl) acryloyl) oxy) tetrahydro-2H-pyran-2-yl) methyl-4-hydroxybenzoate) and 2 (3,5-Dihydroxybenzoic acid) were isolated from B. odorata aerial shoots and their structural elucidation was carried out using 1 and 2D NMR, infrared spectroscopy (IR) and mass spectrometry (ESI-MS). The antimycobacterial activity of various extracts and compounds 1 and 2 was determined using the Microplate Alamar Blue Assay (MABA). The evaluation of the hypolipidemic effect of the ethanolic extract and the glycosylated compound 1 was tested in a murine model of hypercholesterolemia induced by diet and by Triton WR-1339. On the other hand, the LD50 of the ethanolic extract was evaluated in ICR mice by the OECD protocol TG 423. RESULTS: Antimycobacterial assay of hexane, CH2Cl2, EtOAc, ethanolic and aqueous extracts, as well as the new glycosidic compound 1 and benzoic acid derivative 2 isolated from B. odorata showed minimal inhibitory concentrations (MIC) of 100, 12.5, 12.5, 12.5, ≥200, 3.125 and 50 µg/mL, respectively, against Mycobacterium tuberculosis H37Rv. Only hexane and CH2Cl2 extracts were observed to be active against Mycobacterium smegmatis mc2155 at a concentration of 50 and 100 µg/mL, respectively. The ethanolic extract showed lipid-lowering activity at doses of 100 and 1000 mg/kg, while glycosidic compound 1 was active at doses of 50 and 100 mg/kg. In addition, the LD50 of the ethanolic extract was >2000 mg/kg, meaning that this extract does not cause lethality or adverse effects, and no signs of organs alterations or tissue damage were observed. CONCLUSION: The hexane, CH2Cl2, EtOAc, and ethanolic extracts of B. odorata, as well as their components 1 and 2, displayed antimycobacterial activity against M. tuberculosis. Moreover, the ethanolic extract and glycosidic compound 1 showed an important lipid-lowering effect, without lethality or secondary effect. The results of this study support the documented traditional use for B. odorata.


Assuntos
Antituberculosos , Bidens , Hipolipemiantes , Extratos Vegetais , Animais , Antituberculosos/análise , Antituberculosos/farmacologia , Antituberculosos/toxicidade , Feminino , Hipolipemiantes/análise , Hipolipemiantes/farmacologia , Hipolipemiantes/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/toxicidade , Componentes Aéreos da Planta , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Testes de Toxicidade Aguda
14.
J Vis Exp ; (133)2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29578512

RESUMO

Bisphenols, such as bisphenol A (BPA) and bisphenol S (BPS) are polymerizing agents widely used in the production of plastics and numerous everyday-use products. Based on their chemical structure and estradiol-like biological properties, they have been classified as endocrine disrupting compounds (EDC). Long-term exposure to EDCs, even at low doses, has been linked to various health defects including cancer, behavioral disorders and infertility, with greater vulnerability indicated during early developmental periods. Cellular and molecular studies with the genetically tractable nematode model Caenorhabditis elegans have demonstrated that exposure to BPA causes apoptosis, embryonic lethality and disruption in the DNA repair mechanisms. We have previously reported that exposure of C. elegans embryos to low doses of different bisphenols decreases fecundity. In addition, we have shown that the effects of exposure during the very early stages of development persist into adulthood as assayed by quantifying habituation behavior, a form of non-associative learning. Here, we provide detailed protocols for embryonic exposure to low-dose EDCs as well as the associated fecundity and anterior touch habituation assays, along with representative results.


Assuntos
Comportamento Animal/efeitos dos fármacos , Caenorhabditis elegans/patogenicidade , Substâncias Perigosas/efeitos adversos , Reprodução/efeitos dos fármacos , Animais , Humanos
15.
Support Care Cancer ; 26(7): 2353-2359, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29417293

RESUMO

PURPOSE: Ongoing cancer cachexia trials evaluate sarcopenia by skeletal muscle index (SMI) at the L3 vertebrae level, commonly used as a standard. Routine chest CT institutional protocols widely differ in including L3. We investigated whether SMI at L1 assessment, rather than L3, would be reliable and more practicable for non-small cell lung cancer (NSCLC). METHODS: NSCLC patients with routine CT chest had SMI measurements performed at L1 using Slice-O-Matic software. Accuracy of including L1 level, imaging quality, and ability to detect sarcopenia was collected and correlation of L1 SMI with body mass index (BMI) was performed. RESULTS: Thirty-seven patients with NSCLC (73 CT assessments) were enlisted at three institutions. Characteristics: 47% female; medians: age 59, KPS 80%; BMI 25.49, weight 72.97 kg, SMI 59.24. Sarcopenia was detected in 14.7% of patients; 20% had sarcopenic obesity. Of the 73 CTs, 94.5% included L1 (95% CI 86.6-98.5%). Three images (4%) were difficult to evaluate. Inclusion of L1 was similar among the three participating institutions (90.4 to 96.7% inclusion). BMI correlation with SMI was weak (r = 0.329). CONCLUSIONS: SMI assessment at L1 is achievable in patients with NSCLC receiving routine chest CT, with 96% having acceptable quality evaluations. Similar to results previously reported at L3, BMI showed poor correlation and low sensitivity to detect muscle mass loss. The use of CT at L1 is reliable and presents the opportunity for easier patient evaluation of sarcopenia in patients with lung cancer without the need for additional testing or radiation exposure.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/complicações , Região Lombossacral/fisiopatologia , Neoplasias Pulmonares/complicações , Músculo Esquelético/patologia , Sarcopenia/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Sarcopenia/diagnóstico por imagem , Sarcopenia/patologia
16.
Braz. j. microbiol ; 49(supl.1): 269-275, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974344

RESUMO

ABSTRACT Fusarium oxysporum f. sp. lycopersici is a phytopathogenic fungus that causes vascular wilt in tomato plants. In this work we analyze the influence of metal salts such as iron and copper sulphate, as well as that of bathophenanthrolinedisulfonic acid (iron chelator) and bathocuproinedisulfonic acid (copper chelator) on the activity of laccases in the intra (IF) and extracellular fractions (EF) of the wild-type and the non-pathogenic mutant strain (rho1::hyg) of F. oxysporum. The results show that laccase activity in the IF fraction of the wild and mutant strain increased with the addition of iron chelator (53.4 and 114.32%; respectively). With copper, it is observed that there is an inhibition of the activity with the addition of CuSO4 for the EF of the wild and mutant strain (reduction of 82 and 62.6%; respectively) and for the IF of the mutant strain (54.8%). With the copper chelator a less laccase activity in the IF of the mutant strain was observed (reduction of 53.9%). The results obtained suggest a different regulation of intracellular laccases in the mutant strain compared with the wild type in presence of CuSO4 and copper chelator which may be due to the mutation in the rho gene.


Assuntos
Proteínas Fúngicas/metabolismo , Cobre/metabolismo , Lacase/metabolismo , Fusarium/enzimologia , Ferro/metabolismo , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Lycopersicon esculentum/microbiologia , Lacase/genética , Lacase/química , Fusarium/genética , Fusarium/química
17.
Cell Mol Bioeng ; 10(1): 114-123, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31719853

RESUMO

Tumors are much stiffer than healthy tissue, and progressively stiffen as the cancer develops. Tumor stiffening is largely the result of extracellular matrix (ECM) remodeling, for example, deposition and crosslinking of collagen I. Well established in vitro models have demonstrated the influence of the microenvironment in regulating tissue homeostasis, with matrix stiffness being a particularly influential mediator. Non-malignant MCF10A mammary epithelial cells (MECs) lose their epithelial characteristics and become invasive when cultured in stiff microenvironments, leading to the hypothesis that tumor stiffening could contribute directly to disease progression. However, previous studies demonstrating MCF10A invasion have been performed in gels with constant mechanical properties, unlike the dynamically stiffening tumor microenvironment. Here, we employ a temporally stiffening hydrogel platform to demonstrate that matrix stiffening induces invasion from and proliferation in MCF10A mammary acini. After allowing MCF10A acini to form in soft hydrogels for 14 days, the gels were stiffened to the level of a malignant tumor, giving rise to a proliferative and invasive phenotype. Cells were observed to collectively migrate away from mammary acini while maintaining cell-cell contacts. Small molecule inhibition of PI3K and Rac1 pathways was sufficient to significantly reduce the number and size of invasive acini after stiffening. Our results demonstrate that temporal matrix stiffening can induce invasion from mammary acini and supports the notion that tumor stiffening could be implicated in disease progression and metastasis.

18.
Acta Neurobiol Exp (Wars) ; 77(4): 297-304, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29369295

RESUMO

Determining the characteristics of Omitted Stimulus Potential (OSP) parameters using different sensory modalities is important because they reflect timing processes and have a substantial influence on time perception. At the same time, the central mechanisms of time perception associated with sensory processing can modulate cortical brain waves related to cognition. This experiment tested the relationship between parameters of the whole OSP brain wave when trains of auditory, visual or somatosensory stimuli were applied. Twenty healthy young college volunteers completed within­subjects trials with sensory stimuli at a fixed frequency of 0.5 Hz that ceased unpredictably. These passive trials required no behavioural response and were administered to measure the complete set of OSP (i.e., the rate of rise, amplitude and peak latency). OSPs showed a faster rate of rise for auditory stimuli compared to visual or somatosensory stimuli. Auditory stimuli also produced a shorter time to peak and higher amplitude waves. No significant differences were obtained between visual and somatosensory waves. The results suggest that the brain handles interval timing and expectation with greater efficiency for the auditory system compared to other sensory modalities. This auditory supremacy is congruent with previous behavioural studies using missing stimulus tasks and could be useful for clinical purposes, for example, designing auditory­based brain­computer interfaces for patients with motor disabilities and visual impairment. The rate of rise is a dynamic measure that should be included in the ERPs analysis.


Assuntos
Potenciais Evocados/fisiologia , Sensação/fisiologia , Percepção do Tempo/fisiologia , Adulto , Vias Aferentes/fisiologia , Arrestina , Eletroencefalografia , Feminino , Habituação Psicofisiológica/fisiologia , Humanos , Masculino , Estimulação Física , Tempo de Reação/fisiologia , Adulto Jovem
19.
Syst Parasitol ; 93(8): 825-30, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27638736

RESUMO

A new coccidian species (Protozoa: Apicomplexa: Eimeriidae) collected from the red warbler Cardellina rubra (Swainson) is reported from the Nevado de Toluca National Park, Mexico. Isospora cardellinae n. sp. has subspherical oöcysts, measuring on average 26.6 × 25.4 µm, with smooth, bi-layered wall, c.1.3 µm thick. Micropyle, oöcyst residuum, and polar granule are absent. Sporocysts are ovoidal, measuring on average 19.0 × 12.0 µm, with a knob-like Stieda body, a trapezoidal sub-Stieda body and sporocyst residuum composed of scattered spherules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the fourth description of an isosporoid coccidian infecting a New World warbler.


Assuntos
Isospora/classificação , Isospora/citologia , Aves Canoras/parasitologia , Animais , México , Especificidade da Espécie
20.
Protein Expr Purif ; 128: 81-5, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27544923

RESUMO

Brugia malayi (B. malayi) is one of the three causative agents of lymphatic filariasis, a neglected parasitic disease. Current literature suggests that dihydrofolate reductase is a potential drug target for the elimination of B. malayi. Here we report the recombinant expression and purification of a ∼20 kDa B. malayi dihydrofolate reductase (BmDHFR). A His6-tagged construct was expressed in E. coli and purified by affinity chromatography to yield active and homogeneous enzyme for steady-state kinetic characterization and inhibition studies. The catalytic activity kcat was found to be 1.4 ± 0.1 s(-1), the Michaelis Menten constant KM for dihydrofolate 14.7 ± 3.6 µM, and the equilibrium dissociation constant KD for NADPH 25 ± 24 nM. For BmDHFR, IC50 values for a six DHFR inhibitors were determined to be 3.1 ± 0.2 nM for methotrexate, 32 ± 22 µM for trimethoprim, 109 ± 34 µM for pyrimethamine, 154 ± 46 µM for 2,4-diaminoquinazoline, 771 ± 44 µM for cycloguanil, and >20,000 µM for 2,4-diaminopyrimidine. Our findings suggest that antifolate compounds can serve as inhibitors of BmDHFR.


Assuntos
Brugia Malayi/genética , Expressão Gênica , Proteínas de Helminto , Tetra-Hidrofolato Desidrogenase , Animais , Brugia Malayi/enzimologia , Catálise , Proteínas de Helminto/biossíntese , Proteínas de Helminto/química , Proteínas de Helminto/genética , Proteínas de Helminto/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Tetra-Hidrofolato Desidrogenase/biossíntese , Tetra-Hidrofolato Desidrogenase/química , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/isolamento & purificação
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