Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
J Med Entomol ; 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967513

RESUMO

Numerous factors influence insect colonization and development on decomposing remains and can influence postmortem interval (PMI) estimations when insects are used in investigations of suspicious deaths. This study aimed to determine whether insect repellent influences insect colonization of decomposing remains. Pig feet were divided into 4 groups: a control not sprayed with repellent, 40% DEET repellent, 98% DEET repellent, and lemon eucalyptus repellent. The feet were placed in containers, and insect visitation was observed over the course of 3 days, then insects were collected at the end of the third day. This was repeated twice a month from April through November 2022. The analysis focused on the order Diptera. Pairwise comparison determined that there was a significant delay in visitation time for remains with 98% DEET compared to remains with no repellent and 40% DEET. There were significantly fewer adult Diptera collected and more remains with no larvae or eggs present among remains treated with 98% DEET. It was concluded that low concentrations of DEET and lemon eucalyptus repellent did not delay colonization, but that high concentrations of DEET delayed visitation, reduced the number of adult flies collected from the remains, and reduced the likelihood of collecting eggs or larvae from the remains. This contributes to the understanding of factors that can influence insect colonization and development that allow for more accurate PMI estimations by suggesting that insect repellent does not need to be accounted for in PMI estimation, but a high concentration of DEET can deter insects in the short term.

2.
Radiol Bras ; 55(3): 145-150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795608

RESUMO

Objective: To estimate the frequency of lipid-poor adenomas (LPAs) in magnetic resonance imaging (MRI) examinations. Materials and Methods: We retrospectively investigated adrenal lesions on MRI examinations performed in a total of 2,014 patients between January 2016 and December 2017. After exclusions, the sample comprised 69 patients with 74 proven adenomas. Two readers (reader 1 and reader 2) evaluated lesion size, laterality, homogeneity, signal drop on out-of-phase (OP) images, and the signal intensity index (SII). An LPA was defined as a lesion with no signal drop on OP images and an SII < 16.5%. For 68 lesions, computed tomography (CT) scans (obtained within one year of the MRI) were also reviewed. Results: Of the 69 patients evaluated, 42 (60.8%) were women and 27 (39.2%) were men. The mean age was 59.2 ± 14.1 years. Among the 74 confirmed adrenal adenomas evaluated, the mean lesion size was 18.5 ± 7.7 mm (range, 7.0-56.0 mm) for reader 1 and 21.0 ± 8.3 mm (range, 7.0-55.0 mm) for reader 2 (p = 0.055). On the basis of the signal drop in OP MRI sequences, both readers identified five (6.8%) of the 74 lesions as being LPAs. When determined on the basis of the SII, that frequency was three (4.0%) for reader 1 and four (5.4%) for reader 2. On CT, 21 (30.8%) of the 68 lesions evaluated were classified as LPAs. Conclusion: The prevalence of LPA was significantly lower on MRI than on CT. That prevalence tends to be even lower when the definition of LPA relies on a quantitative analysis rather than on a qualitative (visual) analysis.


Objetivo: Estimar a frequência de adenomas pobres em lipídios (APLs) em exames de ressonância magnética (RM). Materiais e Métodos: Investigaram-se, retrospectivamente, as lesões adrenais em exames de RM realizados de janeiro de 2016 a dezembro de 2017. Um total de 2.014 pacientes foi submetido a exames abdominais e, após exclusões, 69 pacientes com 74 adenomas foram recuperados. Determinaram-se o tamanho da lesão, a lateralidade, a homogeneidade, a queda do sinal em imagens fora-de-fase (FF) e o índice de intensidade do sinal (IIS). Foram utilizadas as seguintes definições para APLs: sem queda de sinal nas imagens FF e IIS < 16,5%. Para 68 lesões, havia imagens de tomografia computadorizada (TC), com intervalo de até um ano da RM, que também foram analisadas. Resultados: Sessenta e nove pacientes foram incluídos, sendo 42 mulheres (60,8%) e 27 homens (39,2%). A média de idade foi 59,2 ± 14,1 anos. O tamanho médio do adenoma adrenal foi 18,5 ± 7,7 mm para o leitor 1 (7,0-56,0 mm) e 21,0 ± 8,3 mm (7,0-55,0 mm) para o leitor 2 (p = 0,055). A queda de sinal nas imagens FF mostrou que a frequência de APLs para ambos os leitores foi 6,8% (5/74). Para a análise quantitativa, a frequência foi 4,0% (3/74) para o leitor 1 e 5,4% (4/74) para o leitor 2. A frequência de APLs nas imagens de TC foi 21/68 lesões (30,8%). Conclusão: A prevalência de APLs em imagens de RM foi significativamente menor do que em exames de TC. Essa prevalência tende a ser ainda menor quando a definição de APL é baseada na análise quantitativa (IIS < 16,5%), em vez da análise visual.

3.
Medicina (B Aires) ; 82(4): 496-504, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35904904

RESUMO

BACKGROUND: Information about COVID infection in physicians is limited. This knowledge would allow the implementation of actions to reduce its impact. The objective was determining the incidence of SARSCoV-2 infection in physicians from health institutions in Argentina, its characteristics, and associated factors. METHODS: We conducted a multicenter prospective / retrospective cohort study with nested case-control study. Physicians active at the beginning of the pandemic were included, those on leave due to risk factors were excluded. The incidence of confirmed cases was estimated. We conducted bivariate analyses with various factors and used those significant in a logistic regression. RESULTS: Three hundred and forty three physicians with COVID-infection from 8 centers were included. The incidence of disease was 12.1% and that of global absenteeism related to COVID, 34.1%. Almost 70% of close contacts were work-related. In the multivariate analysis living in Autonomous City of Buenos Aires (CABA) (OR 0.19, p = 0.01), working in high-risk areas (OR 0.22, p = 0.01) and individual transportation (OR 0, 34, p = 0.03) reduced the risk of COVID. The odds of infection increased 5.6 times (p = 0.02) for each close contact isolation. DISCUSSION: The number of close contact isolation increased considerably the risk of infection. Living in Buenos Aires City, individual transportation and working in high-risk areas reduced it. Given the high frequency of close contact in the workplace, we strongly recommend the reinforcement of prevention measures in rest areas and non-COVID-wards.


Introducción: La información sobre COVID en médicos es limitada. Su conocimiento permitiría implementar acciones para reducir su impacto. El objetivo general fue determinar la incidencia de infección por SARS-CoV-2 en médicos de instituciones de salud de Argentina, sus características y factores asociados. Materiales y Métodos: Se realizó un estudio multicéntrico de cohorte prospectiva/retrospectiva con estudio de casos-controles anidado. Se incluyeron médicos activos al inicio de la pandemia no exceptuados por riesgo. Se estimó incidencia de casos confirmados. Se compararon factores asociados en casos y controles y se creó un modelo de regresión logística con las variables significativas del análisis bivariado. Resultados: Se incluyeron 343 médicos con COVID de 8 centros. La incidencia de la enfermedad fue de 12.1% y la de ausentismo global relacionado a COVID, de 34.1%. El 70% de los contactos estrechos fueron laborales. En el análisis multivariado de casos y controles, la residencia en la Ciudad Autónoma de Buenos Aires (OR 0.19, p = 0.01), el trabajo en áreas de alto riesgo (OR 0.22, p = 0.01) y vehículo individual (OR 0.34, p = 0.03) redujeron el riesgo de COVID. El odds de enfermar aumentó 4.6 veces (p = 0.02) por cada aislamiento por contacto estrecho. Discusión: El riesgo de enfermar aumentó considerablemente con cada aislamiento por contacto estrecho. La residencia en Ciudad Autónoma, el traslado en vehículo individual y el trabajo en áreas de alto riesgo lo redujeron. Dada la alta frecuencia de contactos estrechos en el ámbito laboral recomendamos reforzar las medidas de prevención en áreas de descanso y no COVID.


Assuntos
COVID-19 , Médicos , Argentina/epidemiologia , COVID-19/epidemiologia , Estudos de Casos e Controles , Humanos , Incidência , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2
4.
Medicina (B.Aires) ; 82(4): 496-504, 20220509. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1405694

RESUMO

Resumen Introducción: La información sobre COVID en médicos es limitada. Su conocimiento permitiría implementar acciones para reducir su impacto. El objetivo general fue determinar la incidencia de infección por SARS-CoV-2 en médicos de instituciones de salud de Argentina, sus características y factores aso ciados. Materiales y Métodos: Se realizó un estudio multicéntrico de cohorte prospectiva/retrospectiva con estudio de casos-controles anidado. Se incluyeron médicos activos al inicio de la pandemia no exceptuados por riesgo. Se estimó incidencia de casos confirmados. Se compararon factores asociados en casos y controles y se creó un modelo de regresión logística con las variables significativas del análisis bivariado. Resultados: Se incluyeron 343 médicos con COVID de 8 centros. La incidencia de la enfermedad fue de 12.1% y la de ausentismo global relacionado a COVID, de 34.1%. El 70% de los contactos estrechos fueron laborales. En el análisis multivariado de casos y controles, la residencia en la Ciudad Autónoma de Buenos Aires (OR 0.19, p = 0.01), el trabajo en áreas de alto riesgo (OR 0.22, p = 0.01) y vehículo individual (OR 0.34, p = 0.03) redujeron el riesgo de COVID. El odds de enfermar aumentó 4.6 veces (p = 0.02) por cada aislamiento por contacto estrecho. Discusión: El riesgo de enfermar aumentó considerablemente con cada aislamiento por contacto estrecho. La residencia en Ciudad Autónoma, el traslado en vehículo individual y el trabajo en áreas de alto riesgo lo redujeron. Dada la alta frecuencia de contactos estrechos en el ámbito laboral recomendamos reforzar las medidas de prevención en áreas de descanso y no COVID.


Abstract Background: Information about COVID infection in physicians is limited. This knowledge would allow the implementation of actions to reduce its impact. The objective was determining the incidence of SARS-CoV-2 infection in physicians from health institutions in Argentina, its characteristics, and associated factors. Methods: We conducted a multicenter prospective / retrospective cohort study with nested case-control study. Physicians active at the beginning of the pandemic were included, those on leave due to risk factors were excluded. The incidence of confirmed cases was estimated. We conducted bivariate analyses with various factors and used those significant in a logistic regression. Results: Three hundred and forty three physicians with COVID-infection from 8 centers were included. The incidence of disease was 12.1% and that of global absenteeism related to COVID, 34.1%. Almost 70% of close contacts were work-related. In the multivariate analysis living in Autonomous City of Buenos Aires (CABA) (OR 0.19, p = 0.01), working in high-risk areas (OR 0.22, p = 0.01) and individual transportation (OR 0, 34, p = 0.03) reduced the risk of COVID. The odds of infection increased 5.6 times (p = 0.02) for each close contact isolation. Discussion: The number of close contact isolation increased considerably the risk of infection. Living in Buenos Aires City, individual transpor tation and working in high-risk areas reduced it. Given the high frequency of close contact in the workplace, we strongly recommend the reinforcement of prevention measures in rest areas and non-COVID-wards.

5.
Radiol. bras ; 55(3): 145-150, May-june 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1387080

RESUMO

Abstract Objective: To estimate the frequency of lipid-poor adenomas (LPAs) in magnetic resonance imaging (MRI) examinations. Materials and Methods: We retrospectively investigated adrenal lesions on MRI examinations performed in a total of 2,014 patients between January 2016 and December 2017. After exclusions, the sample comprised 69 patients with 74 proven adenomas. Two readers (reader 1 and reader 2) evaluated lesion size, laterality, homogeneity, signal drop on out-of-phase (OP) images, and the signal intensity index (SII). An LPA was defined as a lesion with no signal drop on OP images and an SII < 16.5%. For 68 lesions, computed tomography (CT) scans (obtained within one year of the MRI) were also reviewed. Results: Of the 69 patients evaluated, 42 (60.8%) were women and 27 (39.2%) were men. The mean age was 59.2 ± 14.1 years. Among the 74 confirmed adrenal adenomas evaluated, the mean lesion size was 18.5 ± 7.7 mm (range, 7.0-56.0 mm) for reader 1 and 21.0 ± 8.3 mm (range, 7.0-55.0 mm) for reader 2 (p = 0.055). On the basis of the signal drop in OP MRI sequences, both readers identified five (6.8%) of the 74 lesions as being LPAs. When determined on the basis of the SII, that frequency was three (4.0%) for reader 1 and four (5.4%) for reader 2. On CT, 21 (30.8%) of the 68 lesions evaluated were classified as LPAs. Conclusion: The prevalence of LPA was significantly lower on MRI than on CT. That prevalence tends to be even lower when the definition of LPA relies on a quantitative analysis rather than on a qualitative (visual) analysis.


Resumo Objetivo: Estimar a frequência de adenomas pobres em lipídios (APLs) em exames de ressonância magnética (RM). Materiais e Métodos: Investigaram-se, retrospectivamente, as lesões adrenais em exames de RM realizados de janeiro de 2016 a dezembro de 2017. Um total de 2.014 pacientes foi submetido a exames abdominais e, após exclusões, 69 pacientes com 74 adenomas foram recuperados. Determinaram-se o tamanho da lesão, a lateralidade, a homogeneidade, a queda do sinal em imagens fora-de-fase (FF) e o índice de intensidade do sinal (IIS). Foram utilizadas as seguintes definições para APLs: sem queda de sinal nas imagens FF e IIS < 16,5%. Para 68 lesões, havia imagens de tomografia computadorizada (TC), com intervalo de até um ano da RM, que também foram analisadas. Resultados: Sessenta e nove pacientes foram incluídos, sendo 42 mulheres (60,8%) e 27 homens (39,2%). A média de idade foi 59,2 ± 14,1 anos. O tamanho médio do adenoma adrenal foi 18,5 ± 7,7 mm para o leitor 1 (7,0-56,0 mm) e 21,0 ± 8,3 mm (7,0-55,0 mm) para o leitor 2 (p = 0,055). A queda de sinal nas imagens FF mostrou que a frequência de APLs para ambos os leitores foi 6,8% (5/74). Para a análise quantitativa, a frequência foi 4,0% (3/74) para o leitor 1 e 5,4% (4/74) para o leitor 2. A frequência de APLs nas imagens de TC foi 21/68 lesões (30,8%). Conclusão: A prevalência de APLs em imagens de RM foi significativamente menor do que em exames de TC. Essa prevalência tende a ser ainda menor quando a definição de APL é baseada na análise quantitativa (IIS < 16,5%), em vez da análise visual.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35294686

RESUMO

In the present work, halloysite nanotubes modified with gold nanoparticles (AuNPs-HNT) are successfully prepared by wet chemical method for the catalytic degradation of phenothiazine dyes (azure B (AZB) and toluidine blue O (TBO)) and also cleaner reduction of 4-(4-nitrophenyl)morpholine (4NM) in the sodium borohydride (NaBH4) media. The catalyst is formulated by modifying the HNT support with a 0.964% metal loading using the HNT supports modified with 3-aminopropyl-trimethoxysilane (APTMS) coupling agent to facilitate the anchoring sites to trap the AuNPs and to prevent their agglomeration/aggregation. The AuNPs-HNT catalyst is investigated for structural and morphological characterization to get insights about the formation of the catalyst for the effective catalytic reduction of dyes and 4NM. The microscopic studies demonstrate that AuNPs (2.75 nm) are decorated on the outer surface of HNT. The as-prepared AuNPs-HNT catalyst demonstrates AZB and TBO dye degradation efficiency up to 96% in 10 and 11 min, respectively, and catalytic reduction of 4NM to 4-morpholinoaniline (MAN) is achieved up to 97% in 11 min, in the presence of NaBH4 without the formation of any by-products. The pseudo-first-order rate constant (K1) value of the AuNPs-HNT catalyst for AZB, TBO, and 4NM were calculated to be 0.0078, 0.0055, and 0.0066 s-1, respectively. Moreover, the synthesized catalyst shows an excellent reusability with stable catalytic reduction for 7 successive cycles for both the dyes and 4NM. A plausible mechanism for the catalytic dye degradation and reduction of 4NM by AuNPs-HNT catalyst is proposed as well. The obtained results clearly indicate the potential of AuNPs-HNT as an efficient catalyst for the removal of dye contaminants from the aquatic environments and cleaner reduction of 4NM to MAN, insinuating future pharmaceutical applications.

7.
J. negat. no posit. results ; 6(1): 22-31, ene. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-202397

RESUMO

OBJETIVO: Evaluar el adhesión terapéutica a los tratamientos médicos de urgencia de los atletas de la EIDE de Granma. Material y Método. Se realizó un estudio descriptivo, retrospectivo desde Enero a Abril de 2019. La muestra se escogió por muestreo intencional tras criterios de entrada, quedando constituida por 50 atletas. Se analizaron las variables: edad, sexo, medicamento indicado, porcentaje de adhesión, causas de no adherencia. RESULTADOS: La mayoría de los participantes al estudio fueron hembras (62,5%), la media de edad fue de 13,3 años y el deporte predominante atletismo. Los medicamentos más prescritos fueron los suplementos vitamínicos, analgésicos, relajantes musculares y antimicrobianos. La adhesión fue baja a la amoxicilina (24%), naproxeno (24%) y metocarbamol (16%). La evaluación general de la adhesión terapéutica fue incompleta con un 64%. Los factores que influyeron en la insuficiente adherencia fueron la mejoría de los síntomas (3,33%), Reacciones adversas (6,66 %), Desconocimiento (33,3 %), Olvido del atleta (56,6%). CONCLUSIONES: El personal de Atención Médica y el Departamento de Farmacia de los Centros de Medicina del Deporte, deben realizar un control de farmacovigilancia en la población atlética mediante revisiones periódicas de los planes terapéuticos. Resulta esencial la orientación educativa en la relación paciente-médico en la búsqueda de mayor adhesión a los tratamientos


OBJECTIVE: Evaluating the therapeutic adhesion to the medical treatments of urgency of the athletes of Granma's EIDE. Material and Method. The females were the majority of the participating to the study (62,5 %), the stocking of age went from 13.3 years and the prevailing sports athletics. A descriptive, retrospective study from January to April 2019 came true. You chose the sign for intentional sampling after entrance criteria, getting constituted by 50 athletes. They examined variable: age, sex, indicated medication, percentage of adhesión and causes of no adherence. RESULTS: The most prescribed medications were the vitaminic supplements, analgesics, muscular and antimicrobial relaxants. Adhesion was low to the amoxicilin (24 %), naproxeno (24 %) and metocarbamol (16 %). The general evaluation of the therapeutic adhesion was incomplete with a 64 %. The factors that influenced the insufficient adherence were the improvement of the symptoms (3,33 %), adverse Reactions (6,66 %), Ignorance (33,3 %), the athlete's Oversight (56,6 %). CONCLUSIONS: The staff of Medical Attention and Farmacia's Apartment of Medicina's Centers of Sports, periodic revisions of the therapeutic plans must accomplish farmacovigilancia's control in the athletic intervening population. The educational orientation results essential in the patient medical relation in the search of bigger adhesion to the treatments


Assuntos
Humanos , Feminino , Adolescente , Adesão à Medicação , Atletas/estatística & dados numéricos , Tratamento de Emergência/métodos , Desempenho Atlético , Estudos Retrospectivos , Prescrições de Medicamentos/estatística & dados numéricos , Suplementos Nutricionais , Farmacovigilância , Estilo de Vida , Amoxicilina/uso terapêutico , Naproxeno/uso terapêutico , Metocarbamol/uso terapêutico
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 236: 118281, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32335419

RESUMO

A simple, colorimetric and visual method is described for the determination of cysteamine (CA) using polyvinylpyrrolidone-stabilized silver nanoparticles (PVP-AgNPs) as a colorimetric probe. The sensing method was based on the aggregation of PVP-AgNPs that led to the changes in the color and absorption profile of the probe. The aggregation of PVP-AgNPs in the presence of CA was evidenced by using transmission electron microscopy (TEM), zeta and dynamic light scattering (DLS) measurements. A distinct color transition could be observed with the naked eye from pale yellow color of PVP-AgNPs to purple. PVP-AgNPs probe showed an excellent selectivity towards CA versus other interfering biomolecules, cations and anions. Furthermore, the colorimetric probe had a linear response for CA from 0.1 to 1.0 µM concentration range with the limit of detection (LOD) of 4.9 nM. The prepared probe was successfully utilized for the determination of CA in blood serum as biological samples.


Assuntos
Cisteamina/análise , Nanopartículas Metálicas/química , Povidona/química , Espectrofotometria Ultravioleta/métodos , Ânions , Colorimetria/métodos , Cisteamina/sangue , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Transmissão , Sensibilidade e Especificidade , Prata/química
9.
Materials (Basel) ; 13(4)2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32093015

RESUMO

In this work, Au nanoparticles, supported in Al2O3 nanowires (ANW) modified with (3-aminopropyl)trimethoxysilane were synthetized, for their use as catalysts in the hydrogenation reaction of 4-(2-fluoro-4-nitrophenyl)-morpholine and 4-(4-nitrophenyl)morpholin-3-one. ANW was obtained by hydrothermal techniques and the metal was incorporated by the reduction of the precursor with NaBH4 posterior to superficial modification. The catalysts were prepared at different metal loadings and were characterized by different techniques. The characterization revealed structured materials in the form of nanowires and a successful superficial modification. All catalysts show that Au is in a reduced state and the shape of the nanoparticles is spherical, with high metal dispersion and size distributions from 3.7 to 4.6 nm. The different systems supported in modified-ANW were active and selective in the hydrogenation reaction of both substrates, finding for all catalytic systems a selectivity of almost 100% to the aromatic amine. Catalytic data showed pseudo first-order kinetics with respect to the substrate for all experimental conditions used in this work. The solvent plays an important role in the activity and selectivity of the catalyst, where the highest efficiency and operational stability was achieved when ethanol was used as the solvent.

10.
Vet Sci ; 6(4)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635257

RESUMO

Molecular typing of bacterial isolates provides a powerful approach for distinguishing Mycobacterium bovis (M. bovis) genotypes. It is known that M. bovis strain virulence plays a role in prevalence and spread of the disease, suggesting that strain virulence and prevailing genotypes are associated. However, it is not well understood whether strain virulence correlates with particular genotypes. In this study, we assessed the in vitro intracellular growth of 18 M. bovis isolates in bovine macrophages as an indicator of bacterial virulence and sought a relationship with the genotype identified by spoligotyping. We found 14 different spoligotypes-11 were already known and three spoligotypes had never been reported before. We identified 2 clusters that were phylogenetically related, containing 10 and 6 strains, respectively, and 2 orphan strains. Intracellular growth and phagocytic rates of 18 M. bovis strains were heterogeneous. Our results suggest that M. bovis intracellular growth and phagocytosis are independent of the bacterial lineage identified by spoligotyping.

11.
Materials (Basel) ; 12(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426313

RESUMO

Palladium N,N'-bis(3-allylsalicylidene)o-phenylenediamine complex (PdAS) immobilized onto mesoporous polymeric methyl acrylate (MA) based resins (PdAS(x)-MA, x = 1, 2, 5, or 10 wt.%) were successfully prepared as heterogeneous catalysts for the Heck reaction. The catalysts were synthesized via radical suspension polymerization using PdAS as a metal chelate monomer, divinylbenzene and MA as co-monomers. The effect of the PdAS(x) content on the physicochemical properties of the resins is also reported. The catalysts were characterized by using a range of analytical techniques. The large surface area (>580 m2·g-1) and thermal stability (up to 250 °C) of the PdAS(x)-MA materials allows their application as catalysts in the C-C coupling reaction between iodobenzene and MA in the presence of trimethylamine at 120 °C using DMF as the solvent. The PdAS(10)-MA catalyst exhibited the highest catalytic performance with no significant catalytic loss being observed after five reuses, thereby indicating excellent catalyst stability in the reaction medium.

12.
Elife ; 72018 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-29972352

RESUMO

Coordination of cell growth with division is essential for proper cell function. In budding yeast, although some molecular mechanisms responsible for cell size control during G1 have been elucidated, the mechanism by which cell size homeostasis is established remains to be discovered. Here, we developed a new technique based on quantification of histone levels to monitor cell cycle progression in individual cells with unprecedented accuracy. Our analysis establishes the existence of a mechanism controlling bud size in G2/M that prevents premature onset of anaphase, and controls the overall size variability. While most G1 mutants do not display impaired size homeostasis, mutants in which cyclin B-Cdk regulation is altered display large size variability. Our study thus demonstrates that size homeostasis is not controlled by a G1-specific mechanism alone but is likely to be an emergent property resulting from the integration of several mechanisms that coordinate cell and bud growth with division.


Assuntos
Ciclo Celular , Homeostase , Saccharomyces cerevisiae/citologia , Anáfase , Ciclo Celular/genética , Ciclina B/metabolismo , Fluorescência , Corantes Fluorescentes/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Histonas/biossíntese , Hidroxiureia/farmacologia , Metáfase , Viabilidade Microbiana , Microfluídica , Modelos Biológicos , Mutação/genética , Saccharomyces cerevisiae/genética , Imagem com Lapso de Tempo
13.
Mater Sci Eng C Mater Biol Appl ; 65: 164-71, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27157739

RESUMO

PAMAM-grafted TiO2 nanotubes (PAMAM-TiO2NT) have been synthesized and evaluated as new drug nanocarriers, using curcumin (CUR), methotrexate (MTX), and silibinin (SIL) as model therapeutic compounds. TiO2NT were surface-modified using a silane coupling agent and subsequently conjugated with PAMAM dendrimer of the third generation. The characterization of PAMAM-TiO2NT nanomaterials was performed by FTIR, TEM, N2 adsorption-desorption isotherms, XRD, and TGA techniques, which accounted for a 2.6wt.% of PAMAM grafting in the prepared materials. The drug loading capacity, drug release properties, and cytotoxicity of PAMAM-TiO2NT showed a significant improvement compared to pristine TiO2NT, thus revealing the promising properties of these new materials for drug delivery purposes.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Nanotubos/química , Preparações Farmacêuticas/química , Titânio/química , Sobrevivência Celular/efeitos dos fármacos , Curcumina/química , Curcumina/metabolismo , Curcumina/toxicidade , Liberação Controlada de Fármacos , Células HeLa , Humanos , Metotrexato/química , Metotrexato/metabolismo , Metotrexato/toxicidade , Microscopia Eletrônica de Transmissão , Preparações Farmacêuticas/metabolismo , Silibina , Silimarina/química , Silimarina/metabolismo , Silimarina/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Acta Neurochir Suppl ; 122: 121-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27165890

RESUMO

Intracranial pressure (ICP) monitoring is sometimes required in clinical pictures of stroke, as extensive intraparenchymal hematomas and intracranial bleeding may severely increase ICP, which can lead to irreversible conditions, such as dementia and cognitive derangement. ICP monitoring has been accepted as a procedure for the safe diagnosis of increased ICP, and for the treatment of intracranial hypertension in some diseases. In this work, we evaluated ICP behavior during the induction of an experimental model of autologous blood injection in rats, simulating a hemorrhagic stroke. Rats were subjected to stereotactic surgery for the implantation of a unilateral cannula into the left striatal region of the brain. Autologous blood was infused into the left striatal region with an automatic microinfusion pump. ICP monitoring was performed throughout the procedure of hemorrhagic stroke induction. Analyses consisted of short-time Fourier transform for ICP before and after stroke induction and the histological processing of the animals' brains. Short-time Fourier transform analysis demonstrated oscillations in the ICP frequency components throughout time after the microinjections compared with data before them. Histological analysis revealed neuropathological changes in the striatum in all microinjected animals.


Assuntos
Hemorragia Cerebral/fisiopatologia , Pressão Intracraniana/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Hemorragia Cerebral/complicações , Hemorragia Cerebral/patologia , Corpo Estriado/patologia , Modelos Animais de Doenças , Análise de Fourier , Homeostase , Masculino , Monitorização Fisiológica , Ratos , Ratos Wistar , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/patologia
15.
Curr Biol ; 26(7): 965-71, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27020745

RESUMO

Modern transportation networks have facilitated the migration and mingling of previously isolated populations of plants, animals, and insects. Human activities can also influence the global distribution of microorganisms. The best-understood example is yeasts associated with winemaking. Humans began making wine in the Middle East over 9,000 years ago [1, 2]. Selecting favorable fermentation products created specialized strains of Saccharomyces cerevisiae [3, 4] that were transported along with grapevines. Today, S. cerevisiae strains residing in vineyards around the world are genetically similar, and their population structure suggests a common origin that followed the path of human migration [3-7]. Like wine, coffee and cacao depend on microbial fermentation [8, 9] and have been globally dispersed by humans. Theobroma cacao originated in the Amazon and Orinoco basins of Colombia and Venezuela [10], was cultivated in Central America by Mesoamerican peoples, and was introduced to Europeans by Hernán Cortés in 1530 [11]. Coffea, native to Ethiopia, was disseminated by Arab traders throughout the Middle East and North Africa in the 6(th) century and was introduced to European consumers in the 17(th) century [12]. Here, we tested whether the yeasts associated with coffee and cacao are genetically similar, crop-specific populations or genetically diverse, geography-specific populations. Our results uncovered populations that, while defined by niche and geography, also bear signatures of admixture between major populations in events independent of the transport of the plants. Thus, human-associated fermentation and migration may have affected the distribution of yeast involved in the production of coffee and chocolate.


Assuntos
Cacau/microbiologia , Café/microbiologia , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/isolamento & purificação , Fermentação , Geografia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Meios de Transporte
16.
Rev. colomb. anestesiol ; 43(1): 51-60, Jan.-Mar. 2015. ilus, tab
Artigo em Inglês | LILACS, COLNAL | ID: lil-735046

RESUMO

Introduction: Despite advances in perioperative management, acute pain and postoperative nausea and vomitingcontinue to be significant complications worldwide. The frequency and the implications of these complications for the process of recovery impact clinical findings, patient quality of care, and hospital costs. Materials and methods: A search and systematic review of the literature after 2011 was conducted. Three international guidelines were selected and they were paired-rated for quality using the AGREE II tool. Management recommendations, adjusted to the Colombian setting, were adopted on the basis of expert consensus, using the Delphi methodology. Results: Recommendations were generated for adult patients based on the international pain management guidelines for acute pain, postoperative nausea and vomiting, and transfer of critically ill patients. Some of the recommendations are of general nature while others are specific forparticular situations. They were all adapted to the Colombian context, bearing in mind the use of drugs which have not received approval from the healthcare authorities or which are not included in the Mandatory Healthcare Plan. Conclusions: Updating and standardizing clinical management recommendations based on the literature on international guidelines is a useful process, provided it is adapted to the national context. This process and its outcome may be useful for healthcare providers and has a positive effect on patient safety, practitioner performance and efficient use of resources.


Introducción: A pesar de los avances en el manejo perioperatorio, el dolor agudo y las náuseas y vómito posoperatorio aún son importantes complicaciones a nivel mundial. Su frecuencia de presentación y el grado de afectación en el proceso de recuperación impactan aspectos clínicos, la calidad de la atención de los pacientes y los costos hospitalarios. Materiales y métodos: Se realizó búsqueda y revisión sistemática de la literatura a partir de 2011. Se seleccionaron tres guías internacionales y se calificó la calidad de manera pareada con el instrumento AGREE II. Mediante consenso de expertos y utilizando metodología Delphi, se adaptaron las recomendaciones de manejo adaptadas al medio colombiano. Resultados: Se generaron recomendaciones para pacientes adultos extraídas de las guías de manejo internacional de dolor agudo, náuseas y vómito posoperatorio y transporte de paciente complicado. Algunas de las recomendaciones son generales y otras especificas para situaciones particulares. Todas fueron adaptadas al contexto colombiano teniendo en cuenta medicamentos que no cuentan con registro sanitario o no están incluidos en el Plan Obligatorio de Salud. Conclusiones: La actualización y estandarización de recomendaciones de manejo clínico basadas en la literatura de guías internacionales es un proceso útil siempre y cuando se adapte al contexto nacional. Este proceso y su resultado puede ser utilizado por prestadores de salud e impactar positivamente la seguridad del paciente, el desempeño de los profesionales sanitarios y la eficiencia de los recursos.


Assuntos
Humanos
17.
PLoS One ; 9(6): e99428, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24918601

RESUMO

P-bodies belong to a large family of RNA granules that are associated with post-transcriptional gene regulation, conserved from yeast to mammals, and influence biological processes ranging from germ cell development to neuronal plasticity. RNA granules can also transport RNAs to specific locations. Germ granules transport maternal RNAs to the embryo, and neuronal granules transport RNAs long distances to the synaptic dendrites. Here we combine microfluidic-based fluorescent microscopy of single cells and automated image analysis to follow p-body dynamics during cell division in yeast. Our results demonstrate that these highly dynamic granules undergo a unidirectional transport from the mother to the daughter cell during mitosis as well as a constrained "hovering" near the bud site half an hour before the bud is observable. Both behaviors are dependent on the Myo4p/She2p RNA transport machinery. Furthermore, single cell analysis of cell size suggests that PBs play an important role in daughter cell growth under nutrient limiting conditions.


Assuntos
Transporte Biológico , Ciclo Celular , Grânulos Citoplasmáticos/metabolismo , Saccharomyces cerevisiae/citologia , Microfluídica , Saccharomyces cerevisiae/crescimento & desenvolvimento
18.
Yeast ; 31(5): 167-78, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24610064

RESUMO

Puromycin is an aminonucleoside antibiotic with structural similarity to aminoacyl tRNA. This structure allows the drug to bind the ribosomal A site and incorporate into nascent polypeptides, causing chain termination, ribosomal subunit dissociation and widespread translational arrest at high concentrations. In contrast, at sufficiently low concentrations, puromycin incorporates primarily at the C-terminus of proteins. While a number of techniques utilize puromycin incorporation as a tool for probing translational activity in vivo, these methods cannot be applied in yeasts that are insensitive to puromycin. Here, we describe a mutant strain of the yeast Saccharomyces cerevisiae that is sensitive to puromycin and characterize the cellular response to the drug. Puromycin inhibits the growth of yeast cells mutant for erg6∆, pdr1∆ and pdr3∆ (EPP) on both solid and liquid media. Puromycin also induces the aggregation of the cytoplasmic processing body component Edc3 in the mutant strain. We establish that puromycin is rapidly incorporated into yeast proteins and test the effects of puromycin on translation in vivo. This study establishes the EPP strain as a valuable tool for implementing puromycin-based assays in yeast, which will enable new avenues of inquiry into protein production and maturation.


Assuntos
Antifúngicos/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , Puromicina/farmacologia , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Ribossomos/efeitos dos fármacos , Ribossomos/genética , Ribossomos/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
19.
G3 (Bethesda) ; 3(12): 2163-71, 2013 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-24122055

RESUMO

The budding yeast Saccharomyces cerevisiae is important for human food production and as a model organism for biological research. The genetic diversity contained in the global population of yeast strains represents a valuable resource for a number of fields, including genetics, bioengineering, and studies of evolution and population structure. Here, we apply a multiplexed, reduced genome sequencing strategy (restriction site-associated sequencing or RAD-seq) to genotype a large collection of S. cerevisiae strains isolated from a wide range of geographical locations and environmental niches. The method permits the sequencing of the same 1% of all genomes, producing a multiple sequence alignment of 116,880 bases across 262 strains. We find diversity among these strains is principally organized by geography, with European, North American, Asian, and African/S. E. Asian populations defining the major axes of genetic variation. At a finer scale, small groups of strains from cacao, olives, and sake are defined by unique variants not present in other strains. One population, containing strains from a variety of fermentations, exhibits high levels of heterozygosity and a mixture of alleles from European and Asian populations, indicating an admixed origin for this group. We propose a model of geographic differentiation followed by human-associated admixture, primarily between European and Asian populations and more recently between European and North American populations. The large collection of genotyped yeast strains characterized here will provide a useful resource for the broad community of yeast researchers.


Assuntos
Variação Genética , Genoma Fúngico , Saccharomyces cerevisiae/genética , Análise de Sequência de DNA/métodos , Genética Populacional , Heterozigoto , Filogeografia
20.
Prev Vet Med ; 106(1): 1-8, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22703980

RESUMO

The molecular fingerprints of 878 isolates of Mycobacterium bovis collected from cattle between 2009 and 2010 in different regions of Mexico were used in this study. One hundred and ninety-four spoligotypes were observed in total with a high degree of heterogeneity. Sixty-four percent of the isolates grouped into just nine spoligotypes, and 27% fell into only two spoligotypes: SB0673 and SB0669; 149 were orphan spoligotypes. The two predominant spoligotypes were found in almost all states in Mexico, especially in central Mexico, where there is a high concentration of dairy cattle; however, some spoligotypes were closely associated with restricted geographical areas. The hypothetical evolutionary relationship among spoligotypes was estimated using the spoligoforest program in the spolTools webpage. Four trees with connected components and nine unconnected nodes were found. The biggest tree had SB0140 strain as a root, suggesting this as the oldest strain in the tree. However, the relationship of this spoligotype with SB0673 and SB0669 was weak. The discriminatory power of spoligotyping for this M. bovis sample of isolates was 0.94, and the recent transmission index (RTI) 0.83, suggesting a high rate of recent transmission of some strains of M. bovis in the population. This parameter indicates that new measures are required to stop the dissemination of tuberculosis in cattle.


Assuntos
Técnicas de Tipagem Bacteriana/veterinária , Mycobacterium bovis/classificação , Mycobacterium bovis/genética , Filogenia , Tuberculose Bovina/microbiologia , Animais , Bovinos , Feminino , Masculino , México/epidemiologia , Epidemiologia Molecular , Mycobacterium bovis/isolamento & purificação , Oligonucleotídeos/análise , Tuberculose Bovina/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA