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OBJECTIVES: This study aimed to evaluate the association of chronic diseases and indigenous ethnicity on the poor prognosis of outpatients with coronavirus disease 2019 (COVID-19) and hospitalised patients in Mexico. STUDY DESIGN: The study design is an observational study of consecutive COVID-19 cases that were treated in Mexican healthcare units and hospitals between February 27 and April 27, 2020. METHODS: Epidemiological, clinical and sociodemographic data were analysed from outpatients and hospitalised patients. Cox regression models were used to analyse the risk of mortality after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. RESULTS: In total, 15,529 patients with COVID-19 were characterised; 62.6% of patients were aged older than 40 years, 57.8% were men and 1.4% were of indigenous ethnicity. A high proportion had a history of diabetes (18.4%), hypertension (21.9%) and obesity (20.9%). Among hospitalised patients, 11.2% received health care in the intensive care unit. Advanced age, male sex, indigenous ethnicity and having a history of chronic diseases, such as hypertension, diabetes and obesity, were significantly associated with a high risk of death after SARS-CoV-2 infection. Diabetes and obesity were the comorbidities most highly associated with death through the models used in this study. Moreover, living in Mexico City and Mexico State (where there is easy access to medical services) and walking (rather than driving or getting public transport) were negatively associated with mortality after SARS-CoV-2 infection. CONCLUSIONS: Diabetes, hypertension and obesity combined with older age, male sex and indigenous ethnicity increase the risk of death after SARS-CoV-2 infection in the Mexican population. It is recommended that the incidence of COVID-19 is monitored in indigenous communities, and access to health services is increased nationwide.
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COVID-19/mortalidade , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , SARS-CoV-2 , Adolescente , Adulto , Idoso , COVID-19/etnologia , Comorbidade , Diabetes Mellitus/epidemiologia , Etnicidade , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Obesidade/epidemiologia , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Populações Vulneráveis , Adulto JovemRESUMO
Objetivo. Determinar la toxicidad a dosis repetidas durante 28 días, de la ingestión por vía oral del agua termal de San Antonio de Putina-SAP-(Puno), en un modelo murino. Materiales y métodos. Diseño experimental, se utilizaron diez ratas de experimentación de cepa Holtzman, los que fueron divididos en dos grupos de cinco cada uno: un grupo de estudio, al que se le administró en forma repetida, agua termal traída de SAP, en una dosis de 1000 mg/kg en un volumen de 2 mL/100g, y un grupo control con agua potable esterilizada en el mismo volumen. Se realizaron observaciones clínicas diarias, determinación semanal del peso corporal, y después de 28 días se procedió con el estudio histopatológico de órganos (corazón, riñón, hígado y pulmón) y la determinación de parámetros hematológicos y bioquímicos; previo sacrificio de los animales de experimentación. Resultados. No se produjeron muertes (DL50> 1000 mg/kg) ni alteraciones permanentes de signos clínicos. Se observó aumento de peso, sin diferencias estadísticas entre los grupos. Los resultados hematológicos y bioquímicos reflejaron ligeras variaciones no significativas entre grupos, pero dentro del rango de la normalidad. No se observaron alteraciones histopatológicas. Conclusiones. No se encontraron signos de toxicidad aguda ante la administración de agua termomineral de San Antonio de Putina (Puno) en dosis repetidas por un periodo de 28 días.
Objective. To determine 28-day oral acute toxicity at repeated doses of hot springs water from San Antonio de Putina SAP- (Puno) in rats. Materials and methods. Experimental design, ten Holtzman rats were used, which were divided into two groups of five each: a study group that was exposed to repeated administration of SAP hot spring water in a dose of 1000 mg / kg in a volume of 2 mL/100g; and a control group, which sterilized water was given in the same volume. Daily clinical observations were made, weekly determination of body weight; and after 28 days; previous sacrifice of animals, the histopathological study of organs (heart, kidney, liver and lung) and determination of hematological and biochemical parameters were made. Results. No deaths (LD50> 1000 mg/kg) or permanent alterations of clinical signs were observed. Weight gain without statistical differences between the groups was observed. The hematological and biochemical results showed slight nonsignificant variations between groups, but in normality levels. No histopathological alterations were observed. Conclusions. No signs of acute toxicity were found after 28-days repeated administration of hot spring water from San Antonio de Putina (Puno).
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Animais , Ratos , Balneologia , Testes de Toxicidade Aguda , Fontes Termais , Peru , Terapias Complementares , Medicina TradicionalRESUMO
Resumen ANTECEDENTES: la pandemia de influenza en 2009 renovó el interés por identificar oportunamente casos sospechosos de influenza mediante estudios de laboratorio rutinarios, uno de los más estudiados es la deshidrogenasa láctica (DHL). OBJETIVO: determinar si los pacientes con neumonía por influenza A (H1N1) tienen alteraciones particulares en estudios rutinarios de laboratorio, particularmente en concentraciones de DHL y analizar la implicación pronóstica. MATERIAL Y MÉTODO: estudio de casos y controles de pacientes con diagnóstico confirmado de neumonía por influenza A (H1N1) [caso], y pacientes con neumonía bacteriana (control) atendidos de diciembre de 2013 a julio de 2014. RESULTADOS: se analizaron 31 casos, 45% (n = 14) tenían diagnóstico de neumonía por el virus de la influenza A (H1N1), el 55% restante (n = 17) se consideró de causa bacteriana. La media de edad fue de 38 años (límites: 16-62). Las concentraciones de DHL al momento del diagnóstico fueron, en promedio, de 578.77 UI/L (límites: 191-1096), fue mayor en el grupo con neumonía por influenza A (H1N1) [573 vs 624.7 UI/L, p = 0.366]. En el análisis global las concentraciones de DHL > 350 UI/L al diagnóstico y fin del tratamiento repercutieron fuertemente de manera negativa en la mortalidad (OR: 84.0, IC95%: 4.4754-1576.6044 y OR: 154.0, 8.6261-2749.3255). La supervivencia general fue de 18 días, menor en el grupo de A (H1N1) [4 vs 25 días, p = 0.016). CONCLUSIONES: las concentraciones de DHL > 350 UI/L pueden considerarse un biomarcador de gravedad y repercuten negativamente en la supervivencia de pacientes con neumonía, sin poder discriminar al posible agente etiológico.
Abstract BACKGROUND: The 2009 influenza pandemic renewed interest in timely identification of suspected influenza cases through routine laboratory studies, the most studied is lactic dehydrogenase (DHL). OBJECTIVE: To determine if patients with influenza A (H1N1) pneumonia present particular alterations inside routine laboratory studies, particularly in DHL levels and analyze the prognostic implication. MATERIAL AND METHOD: A case-control study of patients with confirmed diagnosis of influenza A (H1N1) pneumonia (case), and patients with bacterial pneumonia (control) treated from December 2013 to July 2014. RESULTS: Thirty-one cases were analyzed, 45% (n = 14) had a diagnosis of influenza A (H1N1) pneumonia, the remaining 55% (n = 17) was considered of bacterial etiology. The mean age was 38 (16-62) years old. The DHL level at diagnosis time was on average 578.77 IU/L (191-1096), higher in the group with influenza A (H1N1) pneumonia (573 IU/L vs 624.7 IU/L, p = 0.366). In the overall analysis, the levels of DHL > 350 IU/L at diagnosis time and at the end of treatment had a negative impact on mortality (OR: 84.0, 95%CI: 4.4754-1576.6044, and OR: 154.0, 8.6261-2749.3255). Overall survival was 18 days, lower in the A (H1N1) group (4 vs 25 days, p = 0.016). CONCLUSIONS: DHL > 350 IU/L can be considered a severity biomarker, also has a negative impact on the survival of patients with pneumonia without being able to discriminate the possible etiological agent.
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Giardiasis is a worldwide parasitic disease that affects mainly children and immunosuppressed people. Side effects and the emergence of resistance over current used drugs make imperative looking for new antiparasitics through discovering of new biological targets and designing of novel drugs. Recently, it has determined that gastric proton-pump inhibitors (PPI) have anti-giardiasic activity. The glycolytic enzyme, triosephosphate isomerase (GlTIM), is one of its potential targets. Therefore, we employed the scaffold of PPI to design new compounds aimed to increase their antigiardial capacity by inactivating GlTIM. Here we demonstrated that two novel PPI-derivatives (BHO2 and BHO3), have better anti-giardiasic activity than omeprazole in concentrations around 120-130 µM, without cytotoxic effect on mammal cell cultures. The derivatives inactivated GlTIM through the chemical modification of Cys222 promoting local structural changes in the enzyme. Furthermore, derivatives forms adducts linked to Cys residues through a C-S bond. We demonstrated that PPI can be used as scaffolds to design better antiparasitic molecules; we also are proposing a molecular mechanism of reaction for these novel derivatives.
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Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Giardia/metabolismo , Inibidores da Bomba de Prótons/química , Triose-Fosfato Isomerase/metabolismo , Antiprotozoários/química , Sítios de Ligação , Giardia/efeitos dos fármacos , Giardíase/tratamento farmacológico , Humanos , Estrutura Molecular , Omeprazol/farmacologia , Testes de Sensibilidade Parasitária , Proteínas de Protozoários/metabolismo , Triose-Fosfato Isomerase/químicaRESUMO
Enchondroma is the most frequent benign tumor in hand bones. It occasionally occurs in the distal phalanx of the fingers; it is usually an asymptomatic lesion, but pain may occur when it is associated with a fracture. The most recommended treatment is lesion curettage and application of a bone graft, besides fixation as needed. Five cases with location in the distal phalanx are reported, as well as treatment results from January 1978 to May 2010. Of the 5 patients, 4 were females and one was male. The most frequently affected digit was the middle finger followed by the little finger. The most frequent symptom at the time of diagnosis was pain. Lesion curettage was performed in all cases, with the use of an autologous distal radius bone graft in 4 and coralline graft in one. Mean follow-up was 193 months (2-384 months). No complications or relapses were reported.
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Neoplasias Ósseas , Condroma , Falanges dos Dedos da Mão , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Condroma/diagnóstico por imagem , Condroma/cirurgia , Feminino , Humanos , Masculino , Radiografia , Adulto JovemRESUMO
BACKGROUND: Variceal bleeding (VB) is the main cause of death among cirrhotic patients. About 30-50% of early rebleeding is encountered few days after the acute episode of VB. It is necessary to stratify patients with high risk of very early rebleeding (VER) for more aggressive therapies. However, there are few and incompletely understood prognostic models for this purpose. AIMS: To determine the risk factors associated with VER after an acute VB. Assessment and comparison of a novel prognostic model generated by Classification and Regression Tree Analysis (CART) with classic-used models (MELD and Child-Pugh [CP]). PATIENTS AND METHODS: Sixty consecutive cirrhotic patients with acute variceal bleeding. CART analysis, MELD and Child-Pugh scores were performed at admission. Receiver operating characteristic (ROC) curves were constructed to evaluate the predictive performance of the models. RESULTS: Very early rebleeding rate was 13%. Variables associated with VER were: serum albumin (p = 0.027), creatinine (p = 0.021) and transfused blood units in the first 24 hrs (p = 0.05). The area under the ROC for MELD, CHILD-Pugh and CART were 0.46, 0.50 and 0.82, respectively. The value of cut analyzed by CART for the significant variables were: 1) Albumin 2.85 mg/dL, 2) Packed red cells 2 units and 3) Creatinine 1.65 mg/dL the ABC-ROC. CONCLUSION: Serum albumin, creatinine and number of transfused blood units were associated with VER. A simple CART algorithm combining these variables allows an accurate predictive assessment of VER after acute variceal bleeding. Key words: cirrhosis, variceal bleeding, esophageal varices, prognosis, portal hypertension.
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Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/classificação , Hemorragia Gastrointestinal/etiologia , Doença Aguda , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de TempoRESUMO
A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the same region in 2003 and 2004 could not confirm the existence of transgenes, thereby casting doubt on the earlier results. These two studies were based on different sampling and analytical procedures and are thus hard to compare. Here, we present new molecular data for this region that confirm the presence of transgenes in three of 23 localities sampled in 2001. Transgene sequences were not detected in samples taken in 2002 from nine localities, while directed samples taken in 2004 from two of the positive 2001 localities were again found to contain transgenic sequences. These findings suggest the persistence or re-introduction of transgenes up until 2004 in this area. We address variability in recombinant sequence detection by analyzing the consistency of current molecular assays. We also present theoretical results on the limitations of estimating the probability of transgene detection in samples taken from landraces. The inclusion of a limited number of female gametes and, more importantly, aggregated transgene distributions may significantly lower detection probabilities. Our analytical and sampling considerations help explain discrepancies among different detection efforts, including the one presented here, and provide considerations for the establishment of monitoring protocols to detect the presence of transgenes among structured populations of landraces.
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Monitoramento Ambiental , Plantas Geneticamente Modificadas/genética , Transgenes , Zea mays/genética , Sequência de Bases , DNA de Plantas/genética , Fluxo Gênico , Genética Populacional , México , Dados de Sequência Molecular , Alinhamento de SequênciaRESUMO
Recientemente se introdujo en el diagnóstico de malaria una técnica llamada amplificación isotérmica de ácidos nucleicos, que usa el material genético plasmodial. Este escrito revisa la información disponible sobre amplificación isotérmica de ácidos nucleicos, especialmente en el campo del paludismo. Metodología: se revisaron las bases electrónicas Lilacs, Scielo, PubMed (Medline) y Ovid. Resultados: solo se encontraron tres referencias sobre amplificación isotérmica de ácidos nucleicos y malaria pero hubo abundante información sobre amplificación isotérmica de ácidos nucleicos en otras infecciones y campos de la medicina, en especial la infectología. La reacción de amplificación isotérmica de ácidos nucleicos requiere de una ADN polimerasa con actividad de desplazamiento de cadena y cuatro cebadores especialmente diseñados para reconocer seis secuencias distintas. Esto garantiza alta especificidad para la amplificación. Varias alternativas de amplificación isotérmica de ácidos nucleicos se han desarrollado para la identificación de virus, bacterias, micoplasmas, protozoos, hongos y levaduras. Ventajas de amplificación isotérmica de ácidos nucleicos son capacidad de amplificar ácidos nucleicos bajo condiciones isotérmicas (60-65 ºC); posibilidad de lectura y semicuantificación a simple vista y de cuantificación con un turbidímetro; altas sensibilidad y especificidad y, en general, capacidad diagnóstica; rapidez, bajo costo y facilidad de aplicación; tolera los componentes de los medios de cultivo y las sustancias biológicas. Entre las desventajas están que la baja concentración de ADN molde disminuye la eficacia del reconocimiento de los cebadores; la observación de la turbidez fue menos sensible que la visualización de los productos en gel de agarosa teñidos con bromuro de etidio y es crítica la prevención de la contaminación...
Introduction: isothermal nucleic acid amplification (LAMP) was recently reported in the diagnosis of malaria. This uses plasmodial DNA to confi rm the diagnosis. This paper reviews the most relevant available information on LAMP, especially in the field of malaria. Methodology: the electronic databases Lilacs, Scielo, PubMed (Medline) and Ovid, were reviewed. Results: only three references were found on LAMP and malaria but there was abundant information on LAMP and other infections in fields of medicine, mainly in infectious diseases. The LAMP reaction requires a strand displacement DNA polymerase and a system of four primers specifically designed to recognize a total of six different sequences in the DNA target. This guarantees high specificity. Several alternatives of LAMP have been developed to identify viruses, bacteria, mycoplasma, protozoa, fungi and yeast. Advantages of LAMP: ability to amplify nucleic acids under isothermal conditions (60 and 65 ºC9; possibility of semi-quantitative reading by observation and quantitative interpretation using a turbidimeter; high sensitivity and specificity and, in general, diagnostic capacity, speed, low cost and ease of implementation; better performance than PCR when culture media and biological substances are processed. Disadvantages: the low concentration of DNA template reduces the primers effi cacy recognition; turbidimetry was less sensitive than the agarose gel and ethidium bromide analysis, prevention of contamination is critical...
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Diagnóstico , Malária , PlasmodiumRESUMO
Molecular studies were performed to establish the causes of the superior lovastatin productivity of a novel solid-state fermentation (SSF) process, in relation with liquid submerged fermentation (SmF; 20 mg/g vs. 0.65 mg/ml). In SSF, biosynthetic genes lovE and lovF transcripts accumulated to high levels from day 1 to day 7. In this period, lovE transcript showed 4.6-fold higher accumulation levels (transcription) than the highest level detected in SmF (day 5). lovF transcript showed two-fold higher expression than the highest point in SmF. In SmF, the expression was only detected clearly on day 5 and, showing a 50% decrease, on day 7. These results show that the higher lovastatin production in SSF is related to a more intense transcription of these biosynthetic genes. A strong expression of gldB gene in lovastatin SSF indicated that Aspergillus terreus senses osmotic stress during the course of SSF, but not in SmF. However, when a liquid medium of identical concentration was used in SmF, lovastatin production decreased in SSF.
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Aspergillus/metabolismo , Fermentação , Regulação Fúngica da Expressão Gênica , Lovastatina/biossíntese , Aspergillus/genética , Genes Fúngicos , Microbiologia Industrial/métodos , Lovastatina/metabolismo , Transcrição GênicaRESUMO
Con frecuencia en las investigaciones médicas se requiere analizar datos de tipo longitudinal que no pueden ser analizados por los métodos estadísticos clásicos de series cronológicas. El objetivo de este trabajo es presentar la factibilidad del uso del método exploratorio multivariado STATIS (Structuration des Tableaux A Trois Indices de la Statistique) en un estudio antropométrico de una muestra de 57 mujeres adultas mayores de 60 años (rango: 69-82 años) del Gran Santiago, Chile, que fueron estudiadas en 5 ocasiones durante un período de 30 meses. Las variables de interés son las mediciones antropométricas: peso, talla, circunferencia brazo, circunferencia pantorrilla, circunferencia cintura, circunferencia cadera, altura rodilla; medidas cada 6 meses. Las variables peso, circunferencia de brazo, circunferencia de pantorrilla, circunferencia de cintura y circunferencia de cadera, fueron las más correlacionadas con el primer eje de compromiso y responden fundamentalmente a medidas de composición corporal como adiposidad y masa muscular. El eje 2, caracterizado por la talla y la altura de rodilla, responde al tamaño del esqueleto. Los resultados obtenidos sugieren una evolución cronológica regular en los primeros 24 meses de observación, con un cambio de estructura a los 30 meses del estudio, así como una clasificación de grupos con diferente composición corporal.
Although in medical research the use of longitudinal data to analyze short time periods is frequently required, it does not permit the use of classic statistical methods for chronological series. The objective of this study is to present the possibility and plausibility of using the STATIS method (Structuration des Tableaux A Trois Indices de la Statistique), an explorative method for data analysis, in a study of the body composition of a sample of 57 women over 68 years of age in Santiago, Chile who were observed over a period of 30 months. The variables analyzed (measured every 6 months) were the following anthropometric measurements: weight, height, arm circumference, calf circumference, waist circumference, hip circumference and knee height. The results obtained suggested a regular chronological evolution during the first 24 months of observation with a change in structure after 30 months of the study, thereby classifying subjects according to body composition.
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Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Constituição Corporal , Chile , Estudos Longitudinais , Análise Multivariada , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
In arterial hypertension besides reducing blood pressure, we should think about the circadian pressure profile that the patient presents, since the patients non depressors (not descent of arterial pressure during the night with regard to the day) (non-dipper) they associate to a worse cardiovascular prognosis. The purpose of the present study was to determine the circadian pressure profile in patient treated arterial hypertension and never previously treated with antihypertensive medication; and its relationship with the organic damage. They were included in the study to 702 patients with clinical indication for 24 hour ambulatory blood pressure monitoring. The 39% was dipper, 2% extreme dipper, 49.6% non-dipper and 9.4% riser. The patient non dipper had bigger levels of 24 hours systolic blood pressure, night blood pressure and bigger organic damage. The main factors associated to this pattern were the clinic systolic blood pressure, obesity and overalls a filtrate smaller glomerular to 60 ml/min.
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Ritmo Circadiano , Hipertensão/fisiopatologia , Adulto , Pressão Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Objetivos: Determinar la actividad citotóxica de las fracciones procedentes de la combinación 1:1 del extracto etanólico de hojas de Annona muricata L (guanábana) y el extracto acuoso atomizado de la raíz de Kramerialappacea (ratania) en cultivos de líneas celulares cancerosas de glándula mamaria (MCF-7), pulmón (H-460) ysistema nervioso central (SF-268). Materiales y métodos: Para el fraccionamiento de la mezcla 1:1 de Annona mas Krameria se preparó una columna cromatográfica de 50 cm de longitud empleando diclorometano, diclorometano:acetato de etilo y CHCl3:MeOH como sistemas de elusión de polaridad creciente, obteniéndose 186 fracciones. Se evaluaron las fracciones 2 a 83 en cultivo de células cancerosas de glándula mamaria (MCF-7), de pulmón (H-460) y del sistema nervioso central (SF-268). Todas las fracciones fueron ensayadas en duplicado. Aquellas fracciones que presentaronun porcentaje de crecimiento de células cancerosas (por ciento G) <50 por ciento en alguna de las tres líneas celulares fueron ensayadas nuevamente a cinco concentraciones, para determinar finalmente la concentración a la cual se inhibe el 50 por ciento del crecimiento de las células cancerosas (GI50). Se consideraron activas aquellas fracciones con una GI50 <10 µg/mL. Resultados: Las fracciones 7 a 17 procedentes de la asociación de los dos productos naturales frente a loscultivos de las líneas celulares tumorales MCF-7, H-460 y SF-268 mostraron una GI50 de 1,6, 1,4 y 1,4 µg/mL respectivamente. Conclusiones: Las fracciones 7 a 17 procedentes de la asociación de Annona más Krameriamostraron acción citotóxica in vitro frente al cultivo de células cancerosas de glándula mamaria, pulmón y del sistema nervioso central.
Objectives: To determine cytotoxic activity of fractions from a 1:1 combination of an ethanol extract of Annona muricata leaves (soursop) and atomized aqueous extract of Krameria lappacea root (Ratania) in breast (MCF-7), lung (H-460), and central nervous system (SF-268) cancer cell cultures. Material and methods: For fractionating the 1:1 mixture of Annona and Krameria a 50-cm long chromatographic column was prepared using dichloromethane, dicholoromethane: ethyl acetate and ChCl3:MeOH as increasing polarity eluting systems and 186 fractions were obtained. Fractions 2 to 83 were assessed in breast (MCF-7), lung (H-460), and central nervous system (SF-268) cancer cell cultures. All fractions were assessed two times. Those fractions that showed <50% growth of cancer cells (%G) in any of the three cell lines were assayed once again using five different concentrations, in order to determine the concentration where there was a 50% inhibition of cancer cell growth (GI50). Those fractions with a <10 ìg/mL GI50 were considered to be active against cancer cell lines. Results: Fractions 7 to 17 of the association of the two aforementioned natural products has GI50 values reported as 1,6, 1,4, and 1,4 ìg/mL against MCF-7, H-460, and SF-268 cancer cell lines, respectively. Conclusions: Fractions 7 to 17 of the Annona and Krameria combination showed in vitro cytotoxic activity against breast, lung, and central nervous system cancer cultured cells.
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Antineoplásicos , Fitoterapia , Krameriaceae , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Plantas Medicinais , Técnicas de Cultura de Células , Preparações de PlantasRESUMO
To determine the genotoxic risk associated to environmental arsenic exposure, the frequency of micronuclei in buccal cells (BCMN) of people drinking arsenic-contaminated water has been evaluated. A group of 105 individuals from the Antofagasta region (north Chile), and 102 individuals from the area of Concepcion, used as reference group, were included in the study. Arsenic concentration in drinking water was high (0.75 mg/L) in the Antofagasta area, 75-fold the maximum recommended level by WHO (0.01 mg/L), while the values obtained in Concepcion were significantly lower (0.002 mg/L). Individual measures of arsenic exposure were also determined in fingernails, which clearly confirm the existence of chronic exposure in the sampled populations from the Antofagasta region (10.15 microg/g versus 3.57 microg/g). The cytogenetic results indicate that, although the BCMN frequency is higher in exposed than in controls, this increase does not attain statistical significance. When the exposure biomarkers were related with the cytogenetic values, no correlations were observed between BCMN and arsenic content in water or in fingernails. In addition, the genotoxicity values do not seem to be related to the ethnic origin from people belonging to the exposed group. As a conclusion it appears that, in the studied population, the chronic ingestion of arsenic-contaminated water does not induce cytogenetic damage, measured as micronuclei, in the cells of the oral mucous in a significant extent.
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Arsenicais/efeitos adversos , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mucosa Bucal/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Adulto , Chile , Feminino , Humanos , Masculino , Testes para Micronúcleos , Mucosa Bucal/citologia , Unhas/química , Abastecimento de Água/normasRESUMO
In the present study we have evaluated whether or not environmental exposure to arsenic in ground drinking-water results in a significant increase in the frequency of micronuclei (MN) in peripheral blood lymphocytes. Thus, 106 individuals from the Antofagasta region (North Chile), together with 111 individuals from the area of Concepción, were used in this investigation. In the Antofagasta area, arsenic levels in drinking-water as high as 0.750 mg/L were measured. In Concepción, located about 2500 km towards the south and used as reference area, arsenic levels in tap water were as low as 0.002 mg/L. The total content of arsenic in fingernails was determined as a biomarker of individual exposure. The cytogenetic results obtained in this study indicate that in the exposed group the overall frequency of binucleated micronucleated cells (BNMN) is higher than in the reference group, the difference being statistically significant. In addition, no differences were found between the exposed and the reference groups, regarding the cytokinesis-block proliferation index (CBPI). No association was observed between BNMN and arsenic content in water or arsenic in fingernails. On the other hand, when the exposed group was divided according to their Atacameno or Caucasian ethnicity, no significant differences were observed between them. In addition, as usually found in other human biomonitoring studies, sex and age are factors that modulate the frequency of MN in both exposed and reference populations.
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Intoxicação por Arsênico/epidemiologia , Arsênio/análise , Arsênio/toxicidade , Carcinógenos/análise , Exposição Ambiental , Micronúcleos com Defeito Cromossômico , Adulto , Biomarcadores , Células Cultivadas , Chile , Feminino , Testes Hematológicos , Humanos , Linfócitos/citologia , Linfócitos/fisiologia , Masculino , Testes para Micronúcleos , Unhas/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluição Química da Água , Abastecimento de ÁguaRESUMO
Two sets of Saccharomyces cerevisiae strains were compared for their physiological responses to different stress conditions. One group is composed of three strains adapted to controlled laboratory conditions (CEN.PK, LR88 and RS58), whereas the other consisted of five industrial strains (IND1101, SuperStart, LO24, LO41 and Azteca). Most industrial strains showed higher tolerance to heat shock and to an oxidative environment than laboratory strains. Excluding CEN.PK, a similar behavior was observed regarding ethanol production in high sugar concentrations (180 g/l glucose). Addition of acetate (10 g/l) or furfural (2 g/l), in concentrations similar to those found in sugar cane bagasse hydrolysates, decreased cell mass formation and growth rate in almost all strains. CEN.PK and SuperStart showed the highest sensitivity when grown in furfural-containing medium. Acetic acid treatment severely affected cell mass formation and reduced growth rate in all strains; CEN.PK and LO24 were the most resistant. The specific ethanol production rate was not affected by furfural addition. However, specific ethanol production rates decreased in response to acetic acid in four industrial strains, and increased in all laboratory strains and in LO24. No significant correlation was found between the stress tolerance of the strains tested and the transcript accumulation of genes selected by their involvement in the response to each of the stressful environments applied.
Assuntos
Adaptação Fisiológica , Saccharomyces cerevisiae/fisiologia , Ácido Acético/farmacologia , Biomassa , Etanol/metabolismo , Congelamento , Furaldeído/farmacologia , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Inibidores do Crescimento/farmacologia , Temperatura Alta , Concentração Osmolar , Estresse Oxidativo , Polissacarídeos/química , Polissacarídeos/toxicidade , RNA Fúngico/análise , RNA Mensageiro/análise , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismoRESUMO
Objetivo: Determinar el metabolismo del hidrato de cloral en ratas bajo condiciones normales y en ratas con insuficiencia hepática inducida con tetracloruro de carbono. Material y métodos: Se usaron ratas macho de la cepa Hotzman. El proceso de inducción de la insuficiencia hepática se realizó durante 3 días consecutivos; este efecto fue confirmnado a través de cortes histológicos del hígado, administrándose luego hidrato de cloral por vía oral en ambos grupos. Posteriormente, se realizó el dosaje en plasma de tricloroetanol-metabolito activo del hidrato de cloral-por el método de cromatografía gaseosa con un detector de ionización de llama, realizandose la validación de dicho método. Resultados: Se encontró una diferencia significativa en la cantidad de tricloroetanol entre los grupos con y sin insuficiencia hepática. se reporta los períodos de latencia, duración e intensidad del efecto del hidrato de cloral, en todos los grupos en estudio. Conclusiones: El metabolismo puede ser cuantificado a través del dosaje de tricloroetanol, el cual fue realizado optimizando un método existente
Assuntos
Ratos , Hidrato de Cloral , Cromatografia Gasosa , Insuficiência HepáticaRESUMO
Few studies have been performed in Puerto Rico concerning the antimicrobial resistance pattern of clinically significant Gram-negative bacilli. The antimicrobial resistance patterns of 5,590 Gram-negative bacteria obtained from three Community-Private Hospitals (CPH) and three University-Affiliated Hospitals (UAH) were evaluated utilizing the institutions' antimicrobial susceptibility reports for the year 2000. The objectives of this study were: to retrospectively evaluate the reported in vitro resistance of clinical isolates of E. coli, K. pneumoniae, E. cloacae, S. marcescens, P. aeruginosa and A. baumannii to selected standard antibiotics and to compare the antimicrobial resistance patterns between Community-Private (CPH) and University Affiliated hospitals (UAH). E. coli was the most common Gram-negative enteric bacilli in both CPH and UAH. In UAH, E. coli demonstrated a statistically significant higher resistance to the selected beta lactams and amikacin antibiotics but not to ciprofloxacin or gentamicin. For K. pneumoniae, the antimicrobial resistant pattern showed that UAH isolates were significantly more resistant to the tested antibiotics with the exception of ceftriaxone. In CPH, E. cloacae isolates were significantly more resistant to piperacillin-tazobactam, ciprofloxacin and gentamicin, while in UAH this organism was more resistant to amikacin. In UAH, S. marcescens isolates demonstrated a statistically significant higher resistance to all tested antibiotics with the exception of imipenem, which was similar in both hospitals group. Pseudomonas aeruginosa demonstrated a statistically significant higher resistance in UAH to all selected antibiotics with the exception of ciprofloxacin and gentamicin, which was similar in both hospitals group. Acinetobacter baumannii was the most resistant organisms in both hospitals group. UAH isolates were significantly more resistant than CPH isolates for all tested antibiotics. When compare with other large-scale antimicrobial resistance studies, the present study results suggest an apparent higher resistance in the Puerto Rican isolates. The high numbers of antimicrobial resistant Gram-negative bacilli in our study strongly suggest multiple mechanisms of antimicrobial resistance including the presence of extended spectrum and chromosomally derepressed beta-lactamases.