RESUMEN

Herein, a Cs2CO3-promoted N-alkylation of 3-cyano-2(1H)-pyridones containing alkyl groups with diverse alkyl halides to synthesize N-alkyl-2-pyridones over O-alkylpyridines is reported. The use of alkyl dihalides resulted in complex mixtures of N- and O-alkylated products. The primary factor influencing regioselectivity in these reactions is the electronic effects of substituents on the 2(1H)-pyridone ring, as evidenced by the preferential formation of O-alkylpyridines upon the introduction of aryl groups. Remarkably, we efficiently employed CuAAC and Ti(Oi-Pr)4-catalyzed amidation reactions to functionalize N-alkyl-2-pyridones containing propargyl and ester groups, leading to the synthesis of 1,2,3-triazoles and amides, respectively. Moreover, O-alkylpyridines 10 b and 10 d displayed remarkable selectivity toward the A-498 renal cancer cell line with growth inhibition percentages (%GI) of 54.75 and 67.64, respectively. The binding modes of compounds 10 b and 10 d to the PIM-1 kinase enzyme were determined through molecular docking studies.

Asunto(s)

Antineoplásicos , Simulación del Acoplamiento Molecular , Piridonas , Humanos , Piridonas/química , Piridonas/farmacología , Piridonas/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Alquilación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Carbonatos/química , Ensayos de Selección de Medicamentos Antitumorales , Relación Estructura-Actividad , Estructura Molecular , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/antagonistas & inhibidores

RESUMEN

PURPOSE: To evaluate short-term patient reported urinary quality of life scores in patients with prostate cancer treated at our institution with and without perioperative prednisone following Cesium-131 (131Cs) prostate LDR brachytherapy. METHODS AND MATERIALS: We started routinely using a perioperative 7-day course of prednisone at a dose of 5 mg per day, beginning 1 day prior to 131Cs prostate LDR brachytherapy from 2013 with goal of improving acute urinary symptomatology. One hundred consecutive patients treated with prednisone were selected, with comparison to 100 consecutive patients who were not treated with prednisone. We analyzed for differences in mean change with standard deviation (SD) in EPIC and AUA scores at 0.5-1 month and 3 months with or without prednisone by Mann-Whitney U Test. Binary logistic regression was performed to assess for impact of prednisone on postoperative urinary catheter use. RESULTS: Pretreatment EPIC and AUA scores were available in 197 patients. Less reduction in EPIC US score was noted at 0.5-1.0 month in the group who received prednisone with mean change of -22.9 (SD 15.4) when compared to the group who did not receive prednisone with mean change of -31.7 (SD 19.3), p < 0.01, with significance lost at 3 months. There was no significant difference in acute urinary retention requiring postoperative urinary catheter placement with perioperative prednisone (OR 1.13, p = 0.71). CONCLUSIONS: A short course of perioperative low-dose prednisone was associated with less severe worsening in urinary symptoms by the EPIC questionnaire at the 0.5-1.0-month timepoint suggesting some improvement in acute urinary quality of life, although differences did not remain statistically significant at 3 months.

Asunto(s)

Braquiterapia , Neoplasias de la Próstata , Corticoesteroides , Braquiterapia/métodos , Radioisótopos de Cesio , Estudios de Seguimiento , Humanos , Masculino , Prednisona/uso terapéutico , Próstata , Neoplasias de la Próstata/radioterapia , Calidad de Vida

RESUMEN

To ensure a reliable verification of a radiation detector, the right parameters for this response verification must be determined and a specific characterization on the detectors of interest must be performed. These were the main pillars of this study, where four Geiger-Müller at the University of Costa Rica's Cyclotron Facilities' main laboratories were studied and characterized using a 137Cs source. First, a verification of the inverse-square law was performed to corroborate the correct measurement by the detectors as the distance from a 137Cs source to the detectors was varied using a new design for a positioner support to ensure repeatability. This verification yielded a potential fit curve with and equation D=670635 x-1.961 (error percentage of 1.95%) and an R2 value of 0.9836. Then, using combinations of copper plates of widths 1.0 mm and 2.0 mm as attenuators between the source and the detectors, the mass attenuation coefficient for copper was obtained only as a reference value for future calibrations of the detectors. The result for this value was 0.040 cm2 /g. The results obtained in this study and the method developed to achieve these results will serve as a base for calibrations of the detectors at these facilities, which will ensure the safety of the patients and personnel in this building.

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Para asegurar respuesta correcta de un detector de radiación, se deben determinar los parámetros correctos para esta verificación y debe realizarse una caracterización específica de los detectores de interés. Estos fueron los pilares principales de este estudio, donde se estudiaron y caracterizaron 4 detectores Geiger-Müller en los laboratorios principales del Ciclotrón de la Universidad de Costa Rica utilizando una fuente radiactiva de 137Cs. Primero, se realizó una verificación de la ley del inverso-cuadrado para corroborar la medición correcta de los detectores según se varía la distancia entre la fuente de 137Cs al detector utilizando un diseño nuevo de un soporte posicionador para la fuente que asegura la repetibilidad entre experimentos. Esta verificación resultó en una curva de ajuste potencial de ecuación D=670635x-1,961 (porcentaje de error de 1,95%) y un valor de R2 de 0,9836. Luego, utilizando combinaciones de placas de cobre de espesores 1,0 mm y 2,0 mm como atenuadores entre la fuente y los detectores, se obtuvo el coeficiente de atenuación másico para el cobre como un valor de referencia para futuras calibraciones de los detectores. Este resultado fue de 0,040 cm2/g. Los resultados obtenidos en esta investigación y el método desarrollado para lograr estos resultados servirán como una base para una futura confirmación metrológica calibraciones de los detectores en estos laboratorios, lo cual colaborará con la seguridad y protección radiológica de pacientes y trabajadores en este edificio.

Asunto(s)

Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Radiometría/instrumentación , Radiometría/métodos , Universidades , Calibración , Radioisótopos de Cesio , Ciclotrones , Exposición a la Radiación/análisis , Exposición a la Radiación/prevención & control , Costa Rica

RESUMEN

Cosmogenic 7Be was used to evaluate soil loss in a mountainous micro-watershed near Belo Horizonte, Southwest Brazil. Two nearby sites were selected, a reference site in a flat area and an eroded site in a hill slope. At the reference site, soil samples were collected monthly throughout the year in order to evaluate seasonal variations of 7Be inventory in soil and its relation with the precipitation regime. Additionally, rainwater was collected and the expected 7Be soil content was predicted. At the reference site, the 7Be inventory shows seasonal variations, in accordance with the rainy season, and its distribution in the soil profile shows an exponential decrease in depth (h0 = 6.9 ± 0.6 kg m-2; r2 = 0.97). At the eroded site, two soil sampling campaigns were performed in order to measure soil erosion in the watershed. The estimated net erosion was 42.2 ± 3.7 t ha-1, indicating the loss of upper 5mm of soil per year. This corresponds to soil losses in the area in the range from moderate to severe erosion.

Asunto(s)

Berilio/análisis , Radioisótopos/análisis , Erosión del Suelo , Brasil , Lluvia , Suelo/química

RESUMEN

AIMS: To report on the PSA outcomes in men undergoing prostate seed implant (PSI) with Cesium-131 at a single institution. MATERIALS AND METHODS: All patients who underwent prostate brachytherapy with Cesium-131 (131Cs) at our institution and had the potential for at least 24 months of follow up were included in this study. Results are reported for the by NCCN risk group (low, low/high-intermediate, and high), as well as by treatment received (monotherapy, combination external beam radiation + PSI, or trimodal therapy with androgen deprivation). The Phoenix definition (absolute nadir plus 2 ng/mL) was used to define biochemical freedom from disease (BFD). RESULTS: Eight hundred and six men have undergone prostate brachytherapy with Cesium-131 at our institution, and 669 men were included in analysis. Median follow up was 60.0 months (range: 0-144 months). According to NCCN risk categories, 29.9% were low-, 55.6% intermediate-, and 14.5% high-risk. Using the Phoenix criteria, 5/10-year BFD was 97.1/95.3% for patients in the low-risk category, 94.0/90.1% for patients in the intermediate-risk category, and 86.2/56.6% for patients in the high-risk category. PSA ≤0.2 ng/dL at 4 years was predictive of 10 year biochemical control: 96.3% vs 70.4%, p < 0.001. CONCLUSIONS: The present study demonstrates that prostate brachytherapy with 131Cs achieves excellent long-term biochemical control.

Asunto(s)

Braquiterapia/métodos , Radioisótopos de Cesio/uso terapéutico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/radioterapia , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos/uso terapéutico , Terapia Combinada , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/terapia , Factores de Riesgo

RESUMEN

Objective:to describe the incidence of cancer cases in the direct victims of the accident, Groups I and II, and compare with overall cancer incidence rates for the population of Goiânia. Method: A descriptive study is presented herein, on the cohort of patients directly exposed and contaminated (Groups I and II) during the cesium-137 accident, which occurred in Goiania (Midwest Brazil) in 1987. The incident cases of malignant neoplasms diagnosed between 1988 and 2017 are described. Analysis included calculation of the Incidence Rate Ratio (IRR) with 95% confidence intervals (CI95%), according to gender. Results: In the 30-year period (1987-2017) following individual exposure, there were seven cancer cases in six directly exposed victims of the cesium-137 accident. Of these, five neoplasms occurred in men, in the esophagus (1), prostrate (3), bladder (1), and two in women, involving breast cancer (1) and skin melanoma (1). The accumulated incidence rates in the direct victims of the Cesium-137 accident were 327.9/100,000 for men and 148.6/100,000 for women. For the overall population of Goiânia, rates were 221.4/100,000 and 231.2/100,000 in men and women, respectively. The ratios of brute incidence rates (direct victims of Cesium-137/population of Goiânia) were 1.5 (IC95%:0.4;5.9) in men and 0.6 (IC95%:0.1;3.8) in women, with no statistically significant differences. Conclusion: Cancer incidence in the direct victims of the Cesium-137 accident (Groups I and II), according to sex, was not different from the incidence in those not exposed to Cesium-137 in the municipality of Goiânia. Cancer risk was similar to that of the general population of the municipality of Goiânia

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Objetivo: descrever a incidência de casos de câncer nas vítimas diretas do acidente Grupo I e II e comparar com as taxas de incidência de câncer na população de Goiânia. Método: Estudo descritivo da coorte de pacientes diretamente expostos e contaminados (Grupos I e II), no acidente com Césio 137, ocorrido em Goiânia (Brasil), em 1987. Descrevemos os casos incidentes de neoplasia maligna diagnosticados no período entre 1988 e 2017. Foram calculados a razão das taxas de incidência e os intervalos de confiança de 95% (IC95%), segundo o sexo na população de estudo. Resultados: No período de 30 anos (1987-2017), ocorreram sete casos de câncer, em seis vítimas diretas do acidente pelo césio-137. Desses, cinco ocorreram em homens (esôfago [1], próstata [3] e bexiga [1]) e dois, em mulheres (mama [1] e melanoma da pele [1]). As taxas de incidência acumulada nas vítimas diretas do Césio-137 foram de 327,9/100,000 entre homens e de 148,6/100,000 entre as mulheres. Na população de Goiânia, as taxas foram de 221,4/100,000 e 231,2/100,000 em homens e mulheres, respectivamente. As razões das taxas de incidência bruta (vítimas diretas do Césio-137/população de Goiânia) foram 1,5 (IC95%:0,4;5,9) em homens e 0,6 (IC95%:0,1;3,8) em mulheres, não houve diferenças estatisticamente significativas. Conclusão: A incidência de câncer nas vítimas diretas do acidente pelo Césio 137 (Grupos I e II), segundo o sexo, não foi diferente da população não exposta ao Césio-137 do município de Goiânia; portanto, o risco de câncer foi semelhante ao da população geral do Município de Goiânia.

Asunto(s)

Cesio , Radiación , Neoplasias

RESUMEN

Human exposure to ionizing radiation has increased over time, mainly due to medical applications, occupational and environmental exposure, as well as accidents involving radioactive materials. In September 1987, an accident with 137Cesium occurred in Goiânia city, Brazil; the accident started with the removal of a 50.9-TBq 137Cesium source from an abandoned radiotherapy unit. Among the radiation-exposed victims, at least 50 individuals showed symptoms of whole-body and local acute irradiation, and also external or internal contamination. In this report, the purpose was to review and summarize the main results of cytogenetic studies carried out with victims of 137Cesium, for blood collection performed shortly after the accident, and following several years post-exposure. The importance of dose estimates by biological dosimetry is highlighted, and also several lessons that were learned from the initial to follow-up (7-10 years after the accident) studies, mainly by applying the fluorescence in situ hybridization (FISH) method. A relevant aspect discussed on the basis of the results obtained in those studies refers to the incidence of chromosomal translocations, which were directly compared to the initial frequencies of dicentrics that were previously used to estimate the absorbed doses. In general, translocation frequencies were two to three times lower than the dicentric frequencies, and the differences were dose-dependent. Furthermore, regarding attempts to perform retrospective dosimetry (10 years post-accident), the dose estimates using translocation frequencies for victims of 137Cesium indicate the feasibility of this approach only for low level exposure (below 0.5 Gy), while for higher doses there are some limitations, and the requirement to apply appropriate correction factors, which were discussed on the basis of literature data. Apart of this, in general terms, important aspects to be mentioned refer to the need for better care and control of radioactive devices, as well as adequate education programs for professionals and also the population.

Asunto(s)

Radioisótopos de Cesio/efectos adversos , Exposición a la Radiación/efectos adversos , Radiación Ionizante , Liberación de Radiactividad Peligrosa , Radiometría/métodos , Translocación Genética/efectos de la radiación , Humanos , Dosis de Radiación , Estudios Retrospectivos

RESUMEN

PURPOSE: To review brachytherapy use in recurrent head and neck carcinoma (RHNC) with focus on its efficacy and complication rates. MATERIAL AND METHODS: A literature search of PubMed, Ovid, Google Scholar, and Scopus was conducted from 1990 to 2017. Publications describing treatment of RHNC with brachytherapy with or without surgery were included. The focus of this review is on oncologic outcomes and the safety of brachytherapy in the recurrent setting. RESULTS: Thirty studies involving RHNC treatment with brachytherapy were reviewed. Brachytherapy as adjunctive treatment to surgical resection appears to be associated with an improved local regional control and overall survival, when compared with the published rates for re-irradiation utilizing external beam radiotherapy (RT) or brachytherapy alone. Safety data remains variable with different isotopes and dose rates with implantable brachytherapy demonstrating a tolerable side effect profile. CONCLUSIONS: Although surgery remains a mainstay treatment for RHNC, intraoperative interstitial brachytherapy delivery as adjunctive therapy may improve the treatment outcome and may be associated with fewer complication rates as compared to reirradiation using external beam radiotherapy. Further investigations are required to elucidate the role of brachytherapy for RHNC.

RESUMEN

The in situ immobilization of granulated Cs-saturated crystalline silicotitanates (Cs-CST) in fixed-bed columns has been investigated using commercially available phenol formaldehyde (PF) resin as a binding agent. Two types of PF resin were investigated as part of this study both being prepared from resol polymer having a formaldehyde:phenol ratio of 3:1. However, one of the resol polymers had water as the primary solvent and the other ethanol. Both resol polymers were observed to completely infiltrate the space between the Cs-CST beads and also the pores within the beads themselves. PF resin monoliths prepared after curing the water-based resol at 180 °C were considerably less porous than the ethanol-based counterparts cured under the same conditions. The enhanced macroporosity of the resin prepared from the ethanol-based resol was presumably the result from enhanced gas bubble generation. Little or no micro- or mesoporosity was measured using nitrogen porosimetry. For both resins cured at 180 °C, intimate contacts with the Cs-CST beads were observed that were not modified even after complete immersion in water over long time frames. Little or no migration of Cs from Cs-CST to the resin binder was observed. The compressive strength of the Cs-CST-PF resin monoliths was measured and benchmarked against cement monoliths and was found to be two to three times higher than cement in the case of the water-based resin. Leaching of the monoliths was conducted in demineralized water at 90 °C. Normalized Cs mass losses of the order of 1.0 g/m2 were measured after 30 days for the ethanol-based resin monoliths. For the less porous water-based monoliths, the normalized mass loss was one order of magnitude lower. The leaching of monoliths irradiated with a 2-MGy dose of γ radiation showed no difference in Cs mass loss suggesting that the ability to retain Cs of either the CST or PF resin was not affected. PF resins are capable of acting as a mechanically robust, radiation-resistant, and impermeable active secondary barrier reducing the likelihood of Cs entry into the biosphere.

Asunto(s)

Radioisótopos de Cesio/análisis , Descontaminación/métodos , Formaldehído/química , Fenoles/química , Polímeros/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Radiactivos del Agua/análisis , Solventes/química

RESUMEN

Several alkali chlorides were compared for their use in reverse transcription (RT) and PCR of different types of nucleic acid templates. On a test region of biological DNA incapable of forming G quadruplex (G4) structures, Taq DNA polymerase showed similar PCR performance with 50 mM KCl, CsCl, LiCl, and NaCl. In contrast, on a synthetic model polydeoxyribonucleotide prone to G4 formation, good PCR amplification was obtained with 50 mM CsCl, but little or none with LiCl or KCl. Similarly, in RT of a G4-prone model polyribonucleotide, MMLV reverse transcriptase produced a good yield with 50 mM CsCl, mediocre yields with LiCl or without added alkali chloride, and a poor yield with 50 mM KCl. The full RT-PCR assay starting from the G4-prone polyribonucleotide, showed good results with CsCl in both stages, poor results with LiCl, and no product formation with KCl. The model polynucleotides showed fast G quadruplex formation under PCR or RT conditions with 50 mM KCl, but not with CsCl or LiCl. The results argue for the use of CsCl instead of KCl for RT and PCR of G4-prone sequences. No advantage was observed when using the 7-deaza type nucleotide analog c7dGTP in PCR amplification of the G4-prone polydeoxyribonucleotide.

Asunto(s)

ADN/genética , G-Cuádruplex , Polinucleótidos/química , Polinucleótidos/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Reversa/genética , Cesio/química , Cloruros/química , Cloruro de Litio/química , Cloruro de Potasio/química , Cloruro de Sodio/química

RESUMEN

Abstract Background: Systemic Arterial Hypertension (SAH) in the Brazilian population, in populations not exposed to Césio-137, presents a prevalence of 28% nationwide. However, in the group of radioactivity victims, these values are unknown. Objective: To analyze the prevalence of hypertension in patients exposed to Cesium-137 in Goiânia, enrolled in the Sistema de Monitoramento dos Radioacidentados (SISRAD) (Radioactivtity Victims Monitoring System) of the Centro de Assistência aos Radioacidentados (C.A.R.A) (Assistence Center for Radioactivity Victims). Methods: This is a descriptive, observational cross-sectional epidemiological study carried out in Goiânia-Goiás, from August 2013 to October 2014, with a group of patients enrolled in the Sistema de Monitoramento dos Radioacidentados (SISRAD) of the Centro de Assistência a Radioacidentados (C.A.R.A.). A total of 102 radioactive patients were divided into two groups: group 1 with 40 and group 2 with 62 participants. A field survey was conducted with a closed and semi-structured questionnaire in which the following contexts were addressed: sociodemographic profile, life habits and personal background. A database was created using the Google Forms application from the Google Web technologies company. The duly collected and stored data were imported and analyzed in the statistical software SPSS, version 21. Results: The prevalence of SAH reached a total of 25% (12 individuals) of the 48 interviewees, 50% of women (24) and 50% of men (24), of which 22.9% (11) of the radioactivity victims revealed to be smokers. Conclusion: The prevalence of SAH in the radioactivity victims population is similar to that of the population in general.

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Resumo Fundamentos: A Hipertensão Arterial Sistêmica (HAS) na população brasileira, em populações não expostas ao Césio-137, apresenta prevalência de 28% em âmbito nacional. Porém, no grupo de radioacidentados, esses valores são desconhecidos. Objetivo: Analisar a prevalência da HAS em pacientes expostos ao Césio-137 ocorrido em Goiânia, cadastrados no Sistema de Monitoramento dos Radioacidentados (SISRAD) do Centro de Assistência aos Radioacidentados (C.A.R.A). Métodos: Estudo epidemiológico do tipo descritivo, observacional de caráter transversal realizado em Goiânia-Goiás, no período de agosto de 2013 a outubro de 2014, com grupo de pacientes cadastrados no Sistema de Monitoramento dos Radioacidentados (SISRAD) do Centro de Assistência aos Radioacidentados (C.A.R.A). Participaram da pesquisa 48 radioacidentados de um total de 102 que foram subdivididos em dois grupos: grupo 1 com 40 e o grupo 2 com 62 participantes. Realizou-se uma pesquisa de campo com questionário fechado e semi-estruturado em que foram abordados os seguintes contextos: perfil sociodemográfico, hábitos de vida e antecedentes pessoais. Criou-se um banco de dados utilizando-se o aplicativo Google Forms, da empresa de tecnologias na Web Google. Os dados devidamente coletados e armazenados foram importados e analisados no software estatístico SPSS, versão 21. Resultados: Dos 48 entrevistados a prevalência de HAS atingiu um total 25% deles (12 indivíduos), sendo 50% de mulheres (24) e 50% de homens (24), dentre estes, 22,9% (11) dos radioacidentados revelaram ser tabagistas. Conclusão: A prevalência de HAS na população de radioacidentados se manifesta de forma semelhante ao da população em geral.

Asunto(s)

Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Radioisótopos de Cesio/toxicidad , Liberación de Radiactividad Peligrosa , Hipertensión/etiología , Factores Socioeconómicos , Brasil/epidemiología , Prevalencia , Estudios Transversales , Factores de Riesgo , Hipertensión/epidemiología

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Following Venezuelan traditional medicine, females with heavy menstrual blood loss (menorrhagia) drink Brownea grandiceps Jacq. flowers (BG) decoctions to reduce the bleeding. In a previous study, we demonstrated that BG aqueous extract (E) possesses a potent anti-fibrinolytic activity capable of inhibiting plasmin, the main serine-protease that degrades fibrin. It is widely known that plasmin inhibitors are often used as anti-fibrinolytics to reduce bleeding during surgeries with high risk of blood loss such as cardiac, liver, vascular, tooth extraction and large orthopedic procedures, as well as for menorrhagia treatments. The aim of this work was to isolate and characterize from BGE the compound responsible for the reported anti-fibrinolytic activity. MATERIALS AND METHODS: A decoction of BG was prepared; then it was homogenized, centrifuged and lyophilized to obtain BGE. Subsequently the extract was fractionated by gel filtration and reverse phase using HPLC and the active compound was characterized by MALDI-ToF MS. The kinetic parameters of anti-plasmin activity were evaluated by an amidolytic assay using a chromogenic substrate; also the anti-plasmin activity was estimated by fibrin plate method. Data were analyzed by nonparametric statistics. RESULTS: The active compound was a condensed tannin denominated Browplasminin, which is capable of inhibiting the plasmin activity in a dose-dependent manner when measured in fibrin plates or by the amidolytic activity method; it also has a minor effect on the FXa activity. However, it does not affect the activity of other serine-proteases such as trypsin, t-PA or u-PA. Browplasminin consists predominately of heteroflavan-3-ols of catechin with B-type linkages, and extents up to heptadecamers (~ 5000Da), with hexose residues attached to the polymer that presents a high degree of galloylation. Its IC50 for plasmin was 47.80µg/mL and for FXa was 237.08µg/mL, while the Ki were 0.76 and 61.61µg/mL for plasmin and FXa, respectively. CONCLUSIONS: The overall outcome of this study suggests that Browplasminin could be responsible for reducing heavy menstrual bleeding in women because its kinetic parameters showed that is a good plasmin inhibitor.

Asunto(s)

Antifibrinolíticos/farmacología , Fabaceae/química , Fibrinolisina/antagonistas & inhibidores , Extractos Vegetales/farmacología , Antifibrinolíticos/administración & dosificación , Antifibrinolíticos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Flores , Taninos Hidrolizables , Concentración 50 Inhibidora , Medicina Tradicional , Extractos Vegetales/administración & dosificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Venezuela

RESUMEN

At present, selective and efficient removal of cesium ions (Cs+) from nuclear waste is of significant importance but still challenging. In this study, an easy-to-get and low-cost hydrogel adsorbent has been developed for effective adsorption and removal of Cs+ from aqueous environment. The novel Cs+-recognizable poly(acrylic acid-co-benzo-18-crown-6-acrylamide) (poly(AAc-co-B18C6Am)) hydrogel is specifically designed with a synergistic effect, in which the AAc units are designed to attract Cs+ via electrostatic attraction and the B18C6Am units are designed to capture the attracted Cs+ by forming stable 2:1 "sandwich" complexes. The poly(AAc-co-B18C6Am) hydrogels are simply synthesized by thermally initiated free-radical copolymerization and display excellent Cs+ adsorption from commonly coexisting metal ions. Important parameters affecting the adsorption are investigated comprehensively, and the adsorption kinetics and adsorption isotherms are also discussed systematically. The poly(AAc-co-B18C6Am) hydrogels exhibit rapid Cs+ adsorption within 30min and the adsorption process is governed by the pseudo-second order model. Adsorption isotherm results demonstrate that the equilibrium data are well fitted by the Langmuir isotherm model, indicating that the Cs+ adsorption is probably a monolayer adsorption process. Such Cs+-recognizable hydrogel materials based on the host-guest complexation are promising as efficient and feasible candidates for adsorption and removal of radioactive Cs+ from nuclear contaminants.

RESUMEN

Las tecnologías de radiotrazadores y de escaneo son herramientas bien consolidadas para el estudio, análisis y evaluación de los procesos industriales y medioambientales. En este trabajo se sintetizan los principales resultados alcanzados por el Grupo de Aplicaciones Industriales y Medioambientales de los Radiotrazadores en el Departamento de Radioquímica. La tecnología de radiotrazadores se ha empleado con éxito para la caracterización del mezclado en reactores discontinuos, los estudios sobre el comportamiento del 99mTc en aguas naturales y residuales, la calibración y validación del modelo de calidad de agua del río Almendares, la caracterización de un reactor anaerobio para el tratamiento de los residuales en el CAI “Pablo Noriega”, la verificación y validación del modelo DFC en un cristalizador azucarero, el desarrollo de un generador radisotópico de ? / ?, la modelación de la calidad del agua en el segmento medio del río Luyanó, y para la modelación de la calidad del agua en el río Guaire, Caracas, Venezuela. En los últimos años el grupo ha desarrollado y evaluado a nivel de laboratorio radiotrazadores para fluidos orgánicos, particularmente relacionados con la industria del petróleo y para sólidos, empleando como precursor al ?. Mientras la técnica de escaneo se ha utilizado para el perfilaje gamma en torres de destilación de alcohol de los CAI "Héctor Molina”“Heriberto Duquesne" y "Jesús Rabí".

RESUMEN

Flavonoid galetin 3,6-dimethyl ether (FGAL) has been isolated from the aerial parts of Piptadenia stipulaceae and has shown a spasmolytic effect in guinea pig ileum. Thus, we aimed to characterize its relaxant mechanism of action. FGAL exhibited a higher relaxant effect on ileum pre-contracted by histamine (EC50=1.9±0.4×10(-7) M) than by KCl (EC50=2.6±0.5×10(-6) M) or carbachol (EC50=1.8±0.4×10(-6) M). The flavonoid inhibited the cumulative contractions to histamine, as well as to CaCl2 in depolarizing medium nominally Ca(2+)-free. The flavonoid relaxed the ileum pre-contracted by S-(-)-Bay K8644 (EC50=9.5±1.9×10(-6) M) but less potently pre-contracted by KCl or histamine. CsCl attenuated the relaxant effect of FGAL (EC50=1.1±0.3×10(-6) M), but apamin or tetraethylammonium (1mM) had no effect (EC50=2.6±0.2×10(-7) and 1.6±0.3×10(-7) M, respectively), ruling out the involvement of small and big conductance Ca(2+)-activated K(+) channels (SKCa and BKCa, respectively). Either 4-aminopyridine or glibenclamide attenuated the relaxant effect of FGAL (EC50=1.8±0.2×10(-6) and 1.5±0.5×10(-6) M, respectively), indicating the involvement of voltage- and ATP-sensitive K(+) channels (KV and KATP, respectively). FGAL did not alter the viability of intestinal myocytes in the MTT assay and decreased (88%) Fluo-4 fluorescence, indicating a decrease in cytosolic Ca(2+) concentration. Therefore, the relaxant mechanism of FGAL involves pseudo-irreversible noncompetitive antagonism of histaminergic receptors, KV and KATP activation and blockade of CaV1, thus leading to a reduction in cytosolic Ca(2+) levels.

Asunto(s)

Calcio/metabolismo , Flavonoides/farmacología , Íleon/efectos de los fármacos , Contracción Muscular/efectos de los fármacos , Canales de Potasio/agonistas , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , 4-Aminopiridina/farmacología , Animales , Apamina/farmacología , Cloruro de Calcio/antagonistas & inhibidores , Cloruro de Calcio/farmacología , Carbacol/antagonistas & inhibidores , Carbacol/farmacología , Supervivencia Celular/efectos de los fármacos , Cesio/farmacología , Cloruros/farmacología , Flavonoides/antagonistas & inhibidores , Gliburida/farmacología , Cobayas , Histamina/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Íleon/fisiología , Células Musculares/efectos de los fármacos , Bloqueadores de los Canales de Potasio/farmacología , Cloruro de Potasio/antagonistas & inhibidores , Cloruro de Potasio/farmacología , Tetraetilamonio

RESUMEN

Para la aplicación exitosa de la técnica del en estudios de erosión del suelo es necesario establecer correctamente el inventario de referencia que representa la entrada total de este radionúclido a la superficie terrestre. En tal sentido, se selecciona un sitio que no haya sido perturbado ni por la erosión ni por el depósito, reconocido como sitio de referencia. En la práctica encontrar estos sitios suele ser difícil. El objetivo de esta investigación fue establecer el inventario de referencia de para localidades de la provincia de Cienfuegos. Quedó establecido que el intervalo de confianza del inventario de referencia de es [1082; 1266] , con una confiabilidad del 90% y el coeficiente de variación del inventario de referencia en las localidades investigadas fue de 11%. Estos valores están en correspondencia con los reportados por otros autores para sitios similares. Asimismo, se determinó la dependencia lineal entre los inventarios de y los promedios históricos de las precipitaciones, con un coeficiente de correlación de 0.94. Esta función lineal se podrá utilizar en la estimación de los inventarios de referencia donde sea complejo encontrar sitios de referencia y por el contrario se disponga de suficiente información respecto a las precipitaciones.

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For the successful application of the technique in soil erosion studies, it is necessary to establish the reference inventory correctly as it represents the total entrance of this radionuclide into the earth’s surface. In this sense, a site that has not been perturbed neither for the erosion nor for the deposit, is selected as reference site. In practice to find such sites is usually difficult. The objective of this research was to establish the reference inventory of for the studied localities of Cienfuegos province. It was established that the confidence interval at 90% of probability of the reference inventory is [1082; 1266] , and the variation coefficient of the reference inventory in the researched localities was of 11%. These values are in correspondence with those reported by other authors for similar places. Also the lineal dependence between the inventories of and the historical averages of the precipitations was determined, with a correlation coefficient of 0.94. This lineal function will be able to be used to obtain or to confirm the reference inventories from rainfall data.

RESUMEN

Estudo observacional transversal realizado em Goiânia, Goiás, Brasil, em uma amostra de 56% de 111 pessoas, objetivando avaliar a qualidade de vida dos indivíduos expostos ao césio-137 e sua associação com fatores sociodemográficos. Utilizou-se o WHOQOL-BREF e o Sistema de Monitoramento dos Radioacidentados. Os participantes foram divididos segundo critérios internacionais em: Grupo I - radiodermites e/ou dosimetria citogenética acima de 20 rads (n = 33); e Grupo II - dosimetria citogenética ≤ 20 rads (n = 29), totalizando 62 sujeitos. Dentre os domínios do WHOQOL-BREF, o meio ambiente apresentou a média de escores mais alta (59,88; DP = 20,39) e o psicológico a média mais baixa (53,02; DP = 17,98). As associações entre os domínios físico, psicológico e relações sociais foram significativas para a variável idade. Não houve diferença entre grupos. A associação entre os fatores sociodemográficos e qualidade de vida não foi significativa. Os radioacidentados sofrem considerável impacto na qualidade de vida, com persistência de problemas psicossociais, especialmente para aqueles com mais de 41 anos.

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This cross-sectional observational study in Goiânia, Goiás State, Brazil in a sample of 56% of 111 individuals exposed to cesium-137 aimed to evaluate their quality of life and associations with socio-demographic factors. The study used the WHOQOL-BREF and the Monitoring System for Radiation Victims. Participants were divided according to international criteria: Group I - radiation dermatitis and / or cytogenetic dosimetry above 20 rads (n = 33) and Group II - cytogenetic dosimetry ≤ 20 rads (n = 29), totaling 62 subjects. Among the WHOQOL-BREF domains, environment showed the highest mean scores (59.88, SD = 20.39) and psychological the lowest (53.02, SD = 17.98). Associations between the physical, psychological, and social domains were significant for the age variable. There was no difference between groups. The association between socio-demographic factors and quality of life was not significant. Radiation victims suffer considerable impact on quality of life, with persistent psychosocial problems, especially among those older than 41 years.

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Estudio transversal observacional realizado en Goiânia, Goiás, Brasil, con un 56% de 111 individuos para evaluar la calidad de vida de las personas expuestas al cesio-137 y su asociación con factores sociodemográficos. Se utilizó el WHOQOL-BREF y el Sistema de Monitoreo de Radio accidentados. Los participantes fueron divididos: Grupo I - Dosimetría radiodermitis y/o citogenética mayor de 20 rads (n = 33) y Grupo II - dosimetría citogenética ≤ 20 rad (n = 29), de un total de 62 sujetos. Entre los dominios del WHOQOL-BREF, el medio ambiente tenía los puntos más altos de promedio (59,88; SD = 20,39) y el promedio más bajo fue el psicológico (53,02; SD = 17,98). Las asociaciones entre las relaciones físicas, psicológicas y sociales fueron significativas para la variable edad. No hubo diferencias entre los grupos y entre los factores sociodemográficos y de calidad de vida. Los radioaccidentados sufren un impacto considerable en la calidad de vida, con la persistencia de los problemas psicosociales, especialmente para aquellos con más de 41 años.

Asunto(s)

Adulto , Femenino , Humanos , Masculino , Radioisótopos de Cesio/efectos de la radiación , Calidad de Vida , Radiodermatitis/complicaciones , Brasil , Estudios Transversales , Estado de Salud , Impacto Psicosocial , Exposición a la Radiación , Factores Socioeconómicos , Encuestas y Cuestionarios

RESUMEN

O objetivo do presente estudo foi avaliar os efeitos dos processos de irradiação (com dose de 1,5kGy) e embalagem em atmosfera modificada (60% N2 e 40% CO2), aplicados isoladamente ou combinados, na extensão da validade comercial de filés de Tilápia do Nilo (Oreochromis niloticus) resfriados. Nos experimentos, foram utilizados 120 filés separados em lotes, de acordo com o tratamento: (T1) embalagem em ar (controle), (T2) embalagem em atmosfera modificada, (T3) embalagem em ar e irradiação, (T4) embalagem em atmosfera modificada e irradiação. Foram realizadas análises físico-químicas (BVT, TMA, pH, amônia e TBARS), bacteriológicas (contagem de bactérias heterotróficas, aeróbias, mesófilas e psicrotróficas) e avaliação sensorial. Os resultados consistentemente indicaram uma redução progressiva da qualidade do produto com o tempo de armazenamento, a qual foi significativamente mais rápida nas amostras controle do que naquelas submetidas aos demais tratamentos, tendo sido observada uma extensão na validade comercial dos filés embalados em atmosfera modificada e/ou irradiados de 4 dias para aproximadamente duas semanas.

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This paper investigated the effects of modified atmosphere packing (60% N2 and 40% CO2) and irradiation (with a 1.5kGy dose) either used alone or combined on the shelf life of fillets of refrigerated Nile Tilapia. A total of 120 fillets were used in the experiments in order to test four different treatments and included samples: packed in air (control), packed in modified atmosphere, packed in air and irradiated, and finally, packed in modified atmosphere and irradiated. Regular monitoring of physicochemical parameters (TVB, pH, ammonia and TBARS), bacteriological conditions (heterotrophic aerobic mesophilic and psychrotrophic bacteria) and sensory acceptance were performed. The results consistently indicated an increasing deterioration of the fillets with time, however those treated with irradiation, modified atmosphere or both combined had longer shelf lives (around two weeks) in comparison with the control (4 days only).

RESUMEN

This paper investigated the effects of modified atmosphere packing (60% N2 and 40% CO2) and irradiation (with a 1.5kGy dose) either used alone or combined on the shelf life of fillets of refrigerated Nile Tilapia. A total of 120 fillets were used in the experiments in order to test four different treatments and included samples: packed in air (control), packed in modified atmosphere, packed in air and irradiated, and finally, packed in modified atmosphere and irradiated. Regular monitoring of physicochemical parameters (TVB, pH, ammonia and TBARS), bacteriological conditions (heterotrophic aerobic mesophilic and psychrotrophic bacteria) and sensory acceptance were performed. The results consistently indicated an increasing deterioration of the fillets with time, however those treated with irradiation, modified atmosphere or both combined had longer shelf lives (around two weeks) in comparison with the control (4 days only).

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O objetivo do presente estudo foi avaliar os efeitos dos processos de irradiação (com dose de 1,5kGy) e embalagem em atmosfera modificada (60% N2 e 40% CO2), aplicados isoladamente ou combinados, na extensão da validade comercial de filés de Tilápia do Nilo (Oreochromis niloticus) resfriados. Nos experimentos, foram utilizados 120 filés separados em lotes, de acordo com o tratamento: (T1) embalagem em ar (controle), (T2) embalagem em atmosfera modificada, (T3) embalagem em ar e irradiação, (T4) embalagem em atmosfera modificada e irradiação. Foram realizadas análises físico-químicas (BVT, TMA, pH, amônia e TBARS), bacteriológicas (contagem de bactérias heterotróficas, aeróbias, mesófilas e psicrotróficas) e avaliação sensorial. Os resultados consistentemente indicaram uma redução progressiva da qualidade do produto com o tempo de armazenamento, a qual foi significativamente mais rápida nas amostras controle do que naquelas submetidas aos demais tratamentos, tendo sido observada uma extensão na validade comercial dos filés embalados em atmosfera modificada e/ou irradiados de 4 dias para aproximadamente duas semanas.

RESUMEN

This paper investigated the effects of modified atmosphere packing (60% N2 and 40% CO2) and irradiation (with a 1.5kGy dose) either used alone or combined on the shelf life of fillets of refrigerated Nile Tilapia. A total of 120 fillets were used in the experiments in order to test four different treatments and included samples: packed in air (control), packed in modified atmosphere, packed in air and irradiated, and finally, packed in modified atmosphere and irradiated. Regular monitoring of physicochemical parameters (TVB, pH, ammonia and TBARS), bacteriological conditions (heterotrophic aerobic mesophilic and psychrotrophic bacteria) and sensory acceptance were performed. The results consistently indicated an increasing deterioration of the fillets with time, however those treated with irradiation, modified atmosphere or both combined had longer shelf lives (around two weeks) in comparison with the control (4 days only).

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O objetivo do presente estudo foi avaliar os efeitos dos processos de irradiação (com dose de 1,5kGy) e embalagem em atmosfera modificada (60% N2 e 40% CO2), aplicados isoladamente ou combinados, na extensão da validade comercial de filés de Tilápia do Nilo (Oreochromis niloticus) resfriados. Nos experimentos, foram utilizados 120 filés separados em lotes, de acordo com o tratamento: (T1) embalagem em ar (controle), (T2) embalagem em atmosfera modificada, (T3) embalagem em ar e irradiação, (T4) embalagem em atmosfera modificada e irradiação. Foram realizadas análises físico-químicas (BVT, TMA, pH, amônia e TBARS), bacteriológicas (contagem de bactérias heterotróficas, aeróbias, mesófilas e psicrotróficas) e avaliação sensorial. Os resultados consistentemente indicaram uma redução progressiva da qualidade do produto com o tempo de armazenamento, a qual foi significativamente mais rápida nas amostras controle do que naquelas submetidas aos demais tratamentos, tendo sido observada uma extensão na validade comercial dos filés embalados em atmosfera modificada e/ou irradiados de 4 dias para aproximadamente duas semanas.