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1.
Toxins (Basel) ; 16(6)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38922129

RESUMO

Polyamines (PAs) are polycationic biogenic amines ubiquitously present in all life forms and are involved in molecular signaling and interaction, determining cell fate (e.g., cell proliferation, dif-ferentiation, and apoptosis). The intricate balance in the PAs' levels in the tissues will determine whether beneficial or detrimental effects will affect homeostasis. It's crucial to note that endoge-nous polyamines, like spermine and spermidine, play a pivotal role in our understanding of neu-rological disorders as they interact with membrane receptors and ion channels, modulating neuro-transmission. In spiders and wasps, monoamines (histamine, dopamine, serotonin, tryptamine) and polyamines (spermine, spermidine, acyl polyamines) comprise, with peptides and other sub-stances, the low molecular weight fraction of the venom. Acylpolyamines are venom components exclusively from spiders and a species of solitary wasp, which cause inhibition chiefly of iono-tropic glutamate receptors (AMPA, NMDA, and KA iGluRs) and nicotinic acetylcholine receptors (nAChRs). The first venom acylpolyamines ever discovered (argiopines, Joro and Nephila toxins, and philanthotoxins) have provided templates for the design and synthesis of numerous analogs. Thus far, analogs with high potency exert their effect at nanomolar concentrations, with high se-lectivity toward their ionotropic and ligand receptors. These potent and selective acylpolyamine analogs can serve biomedical purposes and pest control management. The structural modification of acylpolyamine with photolabile and fluorescent groups converted these venom toxins into use-ful molecular probes to discriminate iGluRs and nAchRs in cell populations. In various cases, the linear polyamines, like spermine and spermidine, constituting venom acyl polyamine backbones, have served as cargoes to deliver active molecules via a polyamine uptake system on diseased cells for targeted therapy. In this review, we examined examples of biogenic amines that play an essential role in neural homeostasis and cell signaling, contributing to human health and disease outcomes, which can be present in the venom of arachnids and hymenopterans. With an empha-sis on the spider and wasp venom acylpolyamines, we focused on the origin, structure, derivatiza-tion, and biomedical and biotechnological application of these pharmacologically attractive, chemically modular venom components.


Assuntos
Inseticidas , Poliaminas , Venenos de Aranha , Vespas , Animais , Poliaminas/química , Venenos de Aranha/química , Venenos de Aranha/toxicidade , Inseticidas/farmacologia , Inseticidas/química , Inseticidas/toxicidade , Humanos , Aranhas
2.
Curr Org Synth ; 20(1): 77-95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35184705

RESUMO

Advances in molecular probes have recently intensified because they are valuable tools in studying species of interest for human health, the environment, and industry. Among these species, cyanide (CN-) and fluoride (F-) stand out as hazardous and toxic ions in trace amounts. Thus, there is a significant interest in probes design for their detection with diverse diazoles (pyrazole and imidazole) used for this purpose. These diazole derivatives are known as functional molecules because of their known synthetic versatility and applicability, as they exhibit essential photophysical properties with helpful recognition centers. This review provides an overview of the recent progress (2017-2021) in diazole-based sensors for CN- and F- detection, using the azolic ring as a signaling or recognition unit. The discussion focuses on the mechanism of the action described for recognizing the anion, the structure of the probes with the best synthetic simplicity, detection limits (LODs), application, and selectivity. In this context, the analysis involves probes for cyanide sensing first, then probes for fluoride sensing, and ultimately, dual probes that allow both species recognition.


Assuntos
Fluoretos , Humanos
3.
Metabolites ; 11(12)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34940560

RESUMO

Acute mesenteric ischemia, caused by an abrupt interruption of blood flow in the mesenteric vessels, is associated with high mortality. When treated with surgical interventions or drugs to re-open the vascular lumen, the reperfusion process itself can inflict damage to the intestinal wall. Ischemia and reperfusion injury comprise complex mechanisms involving disarrangement of the splanchnic microcirculatory flow and impairment of the mitochondrial respiratory chain due to initial hypoxemia and subsequent oxidative stress during the reperfusion phase. This pathophysiologic process results in the production of large amounts of reactive oxygen (ROS) and nitrogen (RNS) species, which damage deoxyribonucleic acid, protein, lipids, and carbohydrates by autophagy, mitoptosis, necrosis, necroptosis, and apoptosis. Fluorescence-based systems using molecular probes have emerged as highly effective tools to monitor the concentrations and locations of these often short-lived ROS and RNS. The timely and accurate detection of both ROS and RNS by such an approach would help to identify early injury events associated with ischemia and reperfusion and increase overall clinical diagnostic sensitivity. This abstract describes the pathophysiology of intestinal ischemia and reperfusion and the early biological laboratory diagnosis using fluorescent molecular probes anticipating clinical decisions in the face of an extremely morbid disease.

4.
J. Bras. Patol. Med. Lab. (Online) ; 57: e2882021, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1350885

RESUMO

RESUMEN Las arbovirosis son enfermedades virales transmitidas por artrópodos (arthropod-borne virus). Dengue, zica y chikungunya se destacan entre los arbovirus emergentes y reemergentes en los últimos años en todo el mundo. La similitud de los síntomas de estas infecciones hace que el diagnóstico clínico sea ineficaz, dificultando las medidas profilácticas y preventivas para nuevos brotes. El diagnóstico molecular mediante la técnica de reacción en cadena de la polimerasa (PCR) en tiempo real es una de las formas de diagnosticar esas enfermedades. En este estudio se recopiló y evaluó la literatura sobre el diagnóstico de arbovirosis. Nuestro objetivo era responder a una pregunta orientadora: ¿la metodología de PCR en tiempo real es eficaz para diagnosticar arbovirosis? Se buscaron artículos científicos de acceso abierto en las bases de datos Pubmed (50 artículos) y Scielo (107 artículos), entre 2014 y 2019. La selección se realizó utilizando los criterios de inclusión y exclusión, quedando solo 20 artículos. Entre estos, el 85% fueron estudios transversales, el 10% fueron revisiones sistemáticas y el 5% fueron estudios de casos. El período de publicaciones fue del 50% en 2017; 35% en 2016; y 5% en 2014, 2015 y 2019, cada. En cuanto a los virus tratados en los artículos, el 25% de los estudios investigaron sobre el dengue; el 25% el chikungunya y el 20% el virus del Zica. La efectividad del diagnóstico molecular se publicó en el 21% de los artículos (sensibilidad y especificidad); el 53% destacó el límite de detección; 70%, ausencia de reacciones cruzadas; y el 80%, la diferenciación entre virus.

5.
Rev. colomb. ciencias quim. farm ; 49(1): 114-136, Jan.-Apr. 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144342

RESUMO

RESUMEN El diseño eficiente de compuestos aprovechando las características estructurales de las moléculas y la búsqueda eficiente de dianas terapéuticas, ha proporcionado herramientas efectivas en la investigación de nuevos tratamientos cuando esta se enfoca en mecanismos celulares de la enfermedad. Los cambios fenotípicos producidos por la interacción in vitro entre molécula-diana, pueden controlarse cuantitativamente mediante imagenología de células vivas. Para garantizar una interacción adecuada, es necesario considerar diferentes elementos cruciales: 1. Las características estructurales y la dinámica molecular del compuesto a evaluar. 2. La relevancia del blanco para la fisiopatología de interés. Sin embargo, el desconocimiento del panorama general en el descubrimiento de fármacos, desde problemáticas estructurales y celulares, ha enlentecido la búsqueda de nuevos tratamientos. Esta revisión descriptiva de tema presenta algunos aspectos estructurales importantes para la caracterización de compuestos como candidatos terapéuticos, y aproximaciones experimentales para desarrollo de sistemas celulares. Los tópicos discutidos se enfocan en la monitorización por imagenología de células vivas y así mismo proporcionamos ejemplos relevantes. La monitorización de efectos fenotípicos producidos por interacciones entre candidato químico y blanco terapéutico en un sistema celular puede favorecer la búsqueda eficiente de moléculas potencialmente terapéuticas.


SUMMARY The efficient compounds' design taking advantage of the molecule's structural characteristics and efficient search for therapeutic targets has provided effective tools for the research of new treatments when this is focused on disease cellular mechanisms. Phenotypic changes produced by in vitro interaction between molecules and targets can be monitored quantitatively by live cell imaging. To guarantee adequate interaction, it is necessary to consider different crucial elements: 1. Structural characteristics and molecular dynamics of the evaluated compound. 2. Target relevance for the concern physiopathology. However, overview's ignorance of the drug discovery, from structural and cellular problems, has slowed the new treatments research. This literature review presents some important structural aspects for compounds' characterization as therapeutic candidates and experimental approaches for cellular systems development. Subjects discussed are focused on live cell imaging and we also provide relevant examples. Phenotypic monitoring of interactions' produced effects between the chemical candidate and therapeutic target in a cellular system can favor the efficient search of potentially therapeutic molecules.

6.
Scand J Clin Lab Invest ; 79(3): 218-224, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30813849

RESUMO

Most quantitative real-time PCR (qPCR) detection methods use two types of chemistries to measure the expression levels of ChREBP isoforms, hydrolysis probes for ChREBPα and SYBR Green for ChREBPß. Hydrolysis probes are not available to determine the ChREBPß isoform. The aim of this study was to develop a qPCR assay based only on hydrolysis probes for both ChREBP isoforms. Liver and adipose tissue biopsies from patients undergoing elective cholecystectomy surgery were used to perform qPCR. To validate this assay, the results were compared with sequencing and High Resolution Melting (HRM) PCR assays. Direct sequencing was used to determine the sequence showing site where ChREBPß presents its specific splicing (1 b exon/2 exon) in order to design the primers and the probe. We developed a qPCR assay to determine the ChREBP isoforms expression based on hydrolysis probes. It assays showed good efficiency (95.50%, on average), high reproducibility, and a strong linear correlation (R2 ≥ 0.99) for tissues tested. HRM analysis confirmed the specificity of the primers and the result of this assay matched (100%) with the outcomes obtained by sequencing and qPCR. Also, we obtained the ChREBPß sequence showing exon 1b spliced to exon 2, bypassing exon 1a, and retaining the remainder of the ChREBPα exons. Based on the use of hydrolysis probes, our method can efficiently identify the expression of both ChREBP isoforms. Thus, the comparability of the qPCR results using a single chemistry (hydrolysis probes) to discriminate between both ChREBP isoforms was possible.


Assuntos
Tecido Adiposo/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fígado/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Humanos , Omento/metabolismo , Isoformas de Proteínas/metabolismo , Tela Subcutânea/metabolismo
7.
Metro cienc ; 25(2): 7-18, 2017.
Artigo em Espanhol | LILACS | ID: biblio-987068

RESUMO

Objetivo: las mujeres inmigrantes enfrentan problemas para acceder a programas de salud, en relación al tamizaje del cáncer cervical y su prevención. Estudios demuestran que mientras más reciente es la migración (<10 años), es menos probable la realización de exámenes para detectar cáncer cervical. Se plantea la hipótesis de que las mujeres inmigrantes tendrán índices menores de tamizaje de lesiones cervicales causadas por el virus del papiloma humano (HPV) comparadas con las mujeres ecuatorianas. Métodos: se realizó un estudio observacional en 113 mujeres de 17 a 55 años de edad: 56 mujeres inmigrantes/refugiadas y 57 mujeres ecuatorianas Se usó citología cérvico-vaginal y una prueba de detección de ADN del HPV basada en Captura Híbrida II. Las participantes fueron reclutadas mediante selección no probabilística (desde mayo 2014 hasta junio 2015). Las mujeres ecuatorianas fueron incluidas por solicitud voluntaria una vez que recibieron toda la información del proceso; mientras que las mujeres inmigrantes se incluyeron mediante información gráfica y entrevistas, lográndose alianzas entre organizaciones comunitarias dedicadas a ayudarlas y proveedores médicos privados. Resultados: tanto las ecuatorianas (14.15%, n=16) como las inmigrantes (5.3%, n=6) que nunca se realizaron un examen de citología, presentan resultados positivos en el examen de ADN-HPV (alto o bajo riesgo). Las ecuatorianas acceden a la citología cérvico-vaginal, independientemente de su edad, mientas que las mujeres inmigrantes menores de 30 años no han conseguido, hasta el momento del estudio, acceder a este servicio (p < 0.05). Conclusiones: existe una diferencia significativa en los índices de tamizaje de cáncer cervical entre los grupos de inmigrantes /refugiadas y residentes, de acuerdo al lugar de nacimiento y la duración de su estadía en Ecuador.


Objective: immigrant women face health problems and challenges to access health care, no matter what destination country they choose. Regarding cervical cancer screening and prevention, migrant women access to a health care programme is an important issue. Some studies have shown that while migration is recent (under 10 years), is less likely to get cervical cancer examination services comparing with non-immigrant women. The hypothesis stated that immigrant women would have lower rates of screening and a higher prevalence of HPV related lesions, compared to those women from Ecuador. Methods: a 12 months period study was performed including 113 women age 17 to 55, split into two groups: 56 migrant/refugee and 57 Ecuadorian residents, using cervical cytology and a DNA for HPV test based on hybrid capture II. Agreements between community organizations and private providers were reached to help the groups. Results: both groups, Ecuadorian women (14.15%, n=16) and immigrant women (5.3%, n=6) that never had a Papanicolaou test, have HPV-DNA test positive for high and low risk types. Ecuadorian residents have access to cervical cytology regardless their age, while immigrant/refugee women under 30 years have not access to the test, the difference is statistically significant. Conclusions: there is a significant difference in screening levels for cervical cancer between immigrant/refugee women according to place of origin and duration of stay in Ecuador.


Assuntos
Humanos , Feminino , Neoplasias do Colo do Útero , Colo do Útero , Neoplasias Urogenitais , Migrantes , Peneiramento de Líquidos
8.
Rev. panam. salud pública ; 39(1): 19-25, Jan. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-783027

RESUMO

ABSTRACT Objective To determine the use and performance of a line probe assay (LPA) compared with conventional culture and drug sensitivity testing (CDST) in patients registered with tuberculosis (TB) under routine program conditions in Peru in 2011–2013. Methods This was a descriptive, operational research, cross-sectional study of sputum specimens from patients with smear-positive pulmonary TB and mycobacterial cultures from patients with smear-negative or positive TB. Drug resistance to rifampicin and/or isoniazid detected by LPA was compared to CDST. Sensitivity, specificity, and predictive values were calculated and reliability for detecting drug resistance was assessed through kappa coefficient, with values 0.61–0.80 showing substantial correlation, and 0.81 or above showing almost-perfect correlation. Results In 2011–2013, there were 16 169 LPA tests performed, with the proportion of TB patients receiving the test increasing from 3.2% to 30.2%. In all, 2 905 LPA test results were compared to CDST. For LPA in sputum specimens, sensitivity for rifampicin was 92%; isoniazid, 94%; and MDR-TB, 88%; while specificity for rifampicin was 92%; isoniazid, 92%; and MDR-TB, 95%. For LPA in mycobacterial cultures, sensitivity for rifampicin was 95%; isoniazid, 96%; and MDR-TB, 90%; while specificity for rifampicin was 85%; isoniazid, 91%; and MDR-TB, 94%. Kappa coefficients were at 0.81 or above for all comparisons of LPA with CDST using sputum specimens and cultures, except for isoniazid in cultures, which was at 0.79. Conclusions This study suggests that LPA is a reliable and rapid screening test for drug-resistant TB and should be considered suitable for routine use and scale up in Peru.


RESUMEN Objetivo Definir la utilización de un ensayo con sondas en línea y evaluar su desempeño, en comparación con el método convencional de cultivo y antibiograma, en los pacientes registrados con tuberculosis en condiciones programáticas en el Perú del 2011 al 2013. Métodos Investigación operativa descriptiva con un estudio transversal de las muestras de esputo de los pacientes con diagnóstico de tuberculosis pulmonar y baciloscopia positiva y de los cultivos de micobacterias de los pacientes con tuberculosis y baciloscopia positiva o negativa. La farmacorresistencia a la rifampicina, la isoniacida o a ambas, detectada mediante el ensayo con sondas en línea, se comparó con los resultados obtenidos por el método de cultivo y antibiograma. Se calculó la sensibilidad, la especificidad y los valores predictivos del ensayo con sondas en línea y se evaluó su fiabilidad en la detección de la farmacorresistencia mediante el coeficiente k, cuyos valores de 0,61 a 0,80 correspondían a una fuerte correlación y los valores de 0,81 o superiores reflejaban una correlación casi perfecta. Resultados Del 2011 al 2013 se practicaron 16 169 ensayos con sondas en línea, y la proporción de pacientes con diagnóstico de tuberculosis en quienes se practicaba aumentó de 3,2% a 30,2%. En total, se compararon 2 905 resultados del ensayo molecular con el método convencional. En las muestras de esputo, el ensayo molecular ofreció una sensibilidad de 92% para la resistencia a la rifampicina, 94% a la isoniacida y 88% para la tuberculosis multirresistente; su especificidad fue 92% con respecto a la rifampicina, 92% a la isoniacida y 95% a la tuberculosis multirresistente. En los cultivos de micobacterias, el ensayo con sondas en línea mostró una sensibilidad de 95% para la resistencia a la rifampicina, 96% a la isoniacida y 90% para la tuberculosis multirresistente; la especificidad fue 85% para la rifampicina, 91% para la isoniacida y 94% para la tuberculosis multirresistente. El coeficiente k fue 0,81 o superior en todas las comparaciones del ensayo molecular con el método tradicional cuando se usaron muestras de esputo y cultivo, excepto con la isoniacida en cultivo, cuyo coeficiente fue 0,79. Conclusiones Los resultados del presente estudio indican que el ensayo con sondas en línea constituye una prueba de detección fiable y rápida para la tuberculosis multirresistente, y se debe considerar apropiada su utilización en la práctica de rutina y la ampliación de su empleo en el Perú.


Assuntos
Tuberculose/diagnóstico , Ensaio Clínico , Sonda de Prospecção , Peru
9.
Med Mycol ; 53(2): 160-4, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25537280

RESUMO

Fluorescence in situ hybridization (FISH) has been shown to be useful for the detection of Candida and Cryptococcus species in blood culture materials. FISH procedures for the detection of Histoplasma capsulatum var. capsulatum have not been reported so far. This study describes the development and evaluation of fluorescently labeled rRNA-targeting FISH probes to detect and identify H. capsulatum in blood cultures. All three analyzed H. capsulatum reference strains and clinical isolates showed positive signals with the newly designed specific oligonucleotide probes for H. capsulatum, whereas negative reactions were observed for all three nontarget yeast species and the two nontarget bacteria. The assay was also successfully applied for detections of H. capsulatum cells in pre-incubated blood culture samples of patients with clinical suspicion of histoplasmosis (n = 33). The described FISH-based assay was shown to be easy to apply, sensitive, and specific (compared to polymerase chain reaction) for the detection and identification of H. capsulatum in this proof-of-principle analysis. Larger multicentric assessments are recommended for a thorough diagnostic evaluation of the procedure.


Assuntos
Sangue/microbiologia , Histoplasma/isolamento & purificação , Histoplasmose/diagnóstico , Hibridização in Situ Fluorescente/métodos , Técnicas de Diagnóstico Molecular/métodos , Histoplasma/genética , Histoplasmose/microbiologia , Humanos , Sondas de Oligonucleotídeos/genética , RNA Fúngico/genética , RNA Ribossômico/genética , Sensibilidade e Especificidade , Fatores de Tempo
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