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Imagen de apoyo de  The double threat to human health: climate change and its influence on emergence and rapid spread of antibiotic resistance

The double threat to human health: climate change and its influence on emergence and rapid spread of antibiotic resistance

Por: Lina Maria Beltrán Toca | Fecha: 2023

Abstract: At the present time, climate change and antimicrobial resistance are considered as the most critical threats, affecting human, animal, plant, and environmental health. Although these terms may initially appear different, they are interconnected and share similarities in their causes (human interventions and natural cycles), health, and societal consequences. Climate change is associated through direct and indirect pathways with an increase in infectious diseases. Nonetheless, the association between global warming and antimicrobial resistance requires a comprehensive summary of evidence exploring it. Methods: A literature review was conducted to identify and describe the association between climate change and the rapid emergence and spread of antimicrobial resistance. The search was conducted in the following databases: PubMed, Web of Science, Scopus, Embase, Epistemonikos, and Google Scholar. The search period was restricted to articles published from January 2010 to June 2021. Additionally, a snowballing approach was conducted to identify any additional papers. Data extraction included study location, weather factors, environmental elements, antibiotics, and bacteria analysed, as well as the results. Results: 29 articles were included (ten literature or systematic reviews, eight experimental, six ecological, four observational, and one quasi-experimental). In terms of location, all the studies were conducted in countries between 35° and 75° north latitude. The results suggested some evidence of the effects of climate change (alterations in temperature, precipitation, and humidity) on the emergence and rapid spread of antimicrobial resistance in different environments (water, soil, cryosphere, and air). Temperature was described as a main effect of climate change that had effects on antibiotic resistance (increasing bacteria growth, altering metabolism, inducing crossprotection, and facilitating horizontal gene transfer between bacteria). Additionally, results also described the association between altered rain patterns and humidity and antimicrobial resistance, through the runoff of antibiotic molecules or the transport of antibiotic resistance mechanisms to other areas. Conclusions: This literature review has underscored the association between climate change and antimicrobial resistance. According to the results shown in the selected studies, the alterations in weather factors resulting from climate change have varying effects on the emergence and spread of antibiotic resistance. However, further research is imperative to decipher the complex interactions between other environmental processes, pollutants, patterns of antibiotic consumption, wastewater, animal migration, and regions below the latitudes covered in this literature review.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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The double threat to human health: climate change and its influence on emergence and rapid spread of antibiotic resistance

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Imagen de apoyo de  Diagnostic Agreement of Microscopy Observation of Drug Susceptibility assay (MODS+) with Sensititre Myco-TB plate for first- and second-line anti-TB drugs

Diagnostic Agreement of Microscopy Observation of Drug Susceptibility assay (MODS+) with Sensititre Myco-TB plate for first- and second-line anti-TB drugs

Por: Natalia; Lopez Castaño Villegas | Fecha: 2018

Abstract: Background: Multidrug resistant TB cases have been on the rise, risking advances in TB prevalence and control. Early diagnosis and targeted initial treatment are paramount for effective management and control of spreading of MDR/XDR-TB cases Methods: 161 isolates from patients with L-J culture confirmed TB in Lima, Peru, were tested with MODS+ assay, the diagnostic test and Sensititre, the reference standard. Analysis of growth patterns of bacteria in both methods were used to determine susceptibility/resistance of each isolate to three first line and six second line anti-TB agents, using two different critical concentrations (CC) for each antibiotic. Results: Agreement between susceptibility profiles and operational characteristics of diagnostic test yielded high performance and strong agreement with rifampicin 1μg/ml (agreement percent 90%, Kappa value 0.80) and amikacin 1μg/ml (agreement percent 96%, Kappa value 0.81), moderate for isoniazid 0.4μg/ml (agreement percent 89.4%, Kappa value 0.78), moxifloxacin at both CC’s 0.5μg/ml and 0.25μg/ml (agreement percent 93 and kappa values 0.73 for both), levofloxacin 2μg/ml (agreement 93%, kappa 0.69) and amikacin 2μg/ml (agreement 96%, Kappa 0.81), minimal for levofloxacin at CC 1.5μg/ml (agreement 90%, kappa 0.57) kanamycin at both CC’s 10μg/ml and 5μg/ml (agreement 87%, kappa 0.52) and ethionamide 5μg/ml (agreement 89%, kappa 0.46), weak for PAS 10μg/ml (agreement percent 93.9, kappa value 0.29), and none for ethambutol (Kappa value 0.02 for CC 10μg/ml, 0.07 for CC 5μg/ml). Conclusions: MODS+ assay is a cost-effective option for the diagnosis of TB and MDR/XDRTB, specially, in low resource settings with high TB incidence. Further operational research using lower CC’s, results read on different days and placed in settings with high and low TB and MDR/XDRTB burden could offer better sensitivities and wider applicability of results.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Diagnostic Agreement of Microscopy Observation of Drug Susceptibility assay (MODS+) with Sensititre Myco-TB plate for first- and second-line anti-TB drugs

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Imagen de apoyo de  Contribuições da enfermagem para a detecção precoce do câncer de colo uterino = Contributions of nursing to the early detection of cervix cancer

Contribuições da enfermagem para a detecção precoce do câncer de colo uterino = Contributions of nursing to the early detection of cervix cancer

Por: María Angélica Arzuaga Salazar | Fecha: 2011

Resumo: Neste estudo analisam-se o câncer de colo uterino como problema social e as contribuições da enfermagem na realização de testes para detectá-lo precocemente. Metodologicamente se fundamenta na epidemiologia descritiva e na revisão sistemática. Os resultados são apresentados na forma de artigos. No primeiro, Câncer de colo do útero: um problema social mundial, é analisado o câncer de colo de útero como problema social. Estudo transversal, com dados populacionais coletados na base de dados Globocan-2008. Foram utilizados dados das Taxas de Incidência e das Taxas de Mortalidade por 100.000 mulheres e percentuais de risco acumulado de incidência e mortalidade antes dos 75 anos pela doença nas regiões desenvolvidas e em desenvolvimento do mundo. Na análise são aplicadas as classificações da Organização das Nações Unidas (ONU) de desenvolvimento dos países ou regiões com base em projeções sociais e demográficas e os níveis de classificação das Taxas de Incidência e de Mortalidade do International Agency for Research on Cancer (IARC). O segundo artigo, Câncer de colo do útero: mortalidade em Santa Catarina – Brasil, 2000 a 2009, foi desenvolvido com base nos dados dos óbitos de mulheres por câncer de colo do útero, inclusive os de porção não especificada, ocorridos em Santa Catarina no período de 2000 a 2009, obtidos no Sistema de Informação de Mortalidade (SIM) do Ministério da Saúde e do Instituto Brasileiro de Geografia e Estatística (IBGE). Observou-se que as taxas de mortalidade mais elevadas incidiram em mulheres a partir dos trinta anos e que o câncer de colo uterino ainda não foi controlado. No terceiro artigo, A enfermagem na detecção precoce do câncer de colo uterino: revisão sistemática, são analisadas as contribuições da Enfermagem para a título e resumo foram pré-selecionados 174, os quais foram lidos integralmente, resultando na seleção de 10 artigos. O pessoal de enfermagem atuou como participante em nove pesquisas e como pesquisador em três pesquisas. A maioria dos artigos foi classificada com o nível de evidência 3B segundo a classificação Oxford; somente um obteve nível 4. Há contribuição de Enfermagem na realização de exames para detecção precoce do câncer de colo uterino, apesar do nível de evidência com que foram classificados os artigos. Conclui-se que o impacto da doença nas mulheres, nas suas famílias e nas sociedades demanda modificações no quadro das iniquidades sociais com adoção de estratégias intersetoriais que também facilitem o acesso aos serviços de saúde. O cuidado de enfermagem é uma estratégia para atender a responsabilidade social com as mulheres, as famílias e as sociedades e contribuir na detecção precoce da doença, favorecendo a qualidade de vida de milhares de mulheres. Resumen: En este estudio se analizan el cáncer de cuello uterino como problema social y las contribuciones de la enfermería en la realización de pruebas para detectarlo precozmente. Metodológicamente se fundamenta en la epidemiologia descriptiva y en la revisión sistemática. Los resultados son presentados en la forma de artículos. En el primer, El cáncer de cuello de útero: un problema social mundial, es analizado el cáncer de cuello de útero como problema social. Estudio transversal, con datos poblacionales recolectados en la base de datos Globocan-2008. Fueron utilizados datos de las Tasas de Incidencia y de las Tasas de Mortalidad por 100.000 mujeres y porcentajes de riesgo acumulado de incidencia y mortalidad antes de los 75 años por cáncer de cuello uterino en las regiones desarrolladas y en desarrollo. En el análisis son aplicadas las clasificaciones de la Organización de las Naciones Unidas (ONU) de desarrollo de los países o regiones con base en proyecciones sociales y demográficas y los niveles de clasificación de las Tasas de Incidencia y de Mortalidad de la International Agency for Research on Cancer (IARC). El segundo artículo, Cáncer de cuello de útero: mortalidad en Santa Catarina – Brasil, 2000 a 2009, fue desarrollado con base en los datos de las muertes de mujeres por cáncer de cuello de útero, inclusive los de porción no específica, ocurridos en Santa Catarina en el período de 2000 a 2009, obtenidos en el Sistema de Información de Mortalidad (SIM) del Ministerio de Salud y del Instituto Brasileiro de Geografía y Estadística (IBGE). Se observó que las tasas de mortalidad elevadas incidieron en mujeres a partir de los treinta años y que el cáncer de cuello uterino todavía no fue controlado. En el tercer artículo, Contribuciones de la enfermería en la detección precoz del cáncer de cuello de útero: revisión sistemática, son analizadas las contribuciones de la enfermería para la detección precoz de esa neoplasia. Revisión sistemática con artículos recuperados en el año de 2010 en las bases de datos MEDLINE, Cochrane, CINHAHL y LILACS. De los 3091 artículos identificados, después de la lectura del título y resumen fueron preseleccionados 174, los cuales fueron leídos integralmente, resultando en la selección de 10 artículos. El personal de enfermería actuó como participante en nueve investigaciones y como investigador en tres investigaciones. El nivel de evidencia 3B, en la clasificación Oxford, ocurrió en la mayoría de los artículos; solamente uno obtuvo nivel 4. Hay contribuciones de enfermería en la realización de exámenes para detección precoz del cáncer de cuello uterino, a pesar del nivel de evidencia en el que fueron clasificados los artículos. Se concluye que el impacto de la enfermedad en las mujeres, en las familias y en las sociedades demanda modificaciones en el cuadro de las inequidades sociales con adopción de estrategias intersectoriales que también faciliten el acceso a los servicios de salud. El cuidado de enfermería es una estrategia para atender la responsabilidad social con las mujeres, las familias y las sociedades y contribuir en la detección precoz de la enfermad, favoreciendo la calidad de vida de millares de mujeres. Abstract: In this study cervix cancer is analyzed as a social problem and the contribution of nursing in applying screening tests for the early detection of cervical cancer. Methodology is based on descriptive epidemiology and a systematic review. The results were presented like articles. In the first article, Cervical cancer: a social problem, and analyzing cervical cancer as a social problem. Cross sectional Study, with population data collected using the Globocan-2008 databases. Data from incidence and mortality rates per 100.000 women, and accumulated risk rates of cervical cancer incidence and mortality before the age of 75 in developed and developing regions of the world were used. In the analysis, the United Nations Organization classifications of countries or regions development based on social and demographic projections and the levels of classification of the incidence and mortality rates of the International Agency for Research on Cancer (IARC) are applied. The second article, Cervical Cancer: Mortality in Santa Catarina – Brazil, 2000 to 2009, obtained from the Information Mortality System (SIM) of the Ministry of Health and the Brazilian Institute of Geography and Statistics (IBGE). It was observed that the Mortality rate was higher in women in their early thirties and in whom the cervical cancer was not yet controlled. In the third article, Contributions of Nursing in the early detection of cervical cancer: systematic review. The contributions of nursing for the early detection of the disease were analyzed. Systematic review with articles recovered in the year of 2010 from MEDLINE, Cochrane, CINAHL and LILACS databases. After reading the titles and abstracts of the articles, from 3091 identified, 174 were pre-selected and read exhaustively resulting in the selection of 10 articles. The nursing staff participated in nine of the researches and in three of them they participated as researchers. Most of the articles had a level of evidence 3B, in the Oxford classification; only one of them had a level 4. There are also nursing contributions in the application of tests for the early detection of cervical cancer despite the level of evidence in which the articles were classified. It is concluded that the impact of the disease in women, their families and the society demand modifications in the role of social inequities with the adoption of inter-sector strategies that also facilitate the access to health services. Nursing care is a strategy to attend the social responsibility with women, their families and the society and contribute in the early detection of diseases, favoring the quality of life of millions of women.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Contribuições da enfermagem para a detecção precoce do câncer de colo uterino = Contributions of nursing to the early detection of cervix cancer

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Imagen de apoyo de  The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

Por: Stefany Brigetty Guarnizo Peralta | Fecha: 2021

Abstract: Background: Seasonal Influenza is considered to be a cyclic and ordered sequence of values, influenced by external factors that can be predicted and used to detect disease outbreaks and monitoring. In machine learning, the key challenges that limit these analyses are in model explainability and limitations associated with ecological bias. Aim: Determine the best environmental variable selection method to predict Seasonal Influenza in Norway, using an environmental medicine approach combined with machine learning techniques. Methods: This is a quasi-experimental study that compares three approaches (non-variable selection, isolate component, and multipollutant mixture), represented in five methods (univariable, bivariable, multivariable AME, multivariable PCA, multivariable LDA). Per method, the best co-variable combination will be performed, following the internal rules of each method. The best covariable combination is the result of three components: variable selection, validation data set and lag. The first one involves 13 environmental variables (temperature, relative humidity, specific humidity, air pressure, wind speed, precipitation, CO, NO, NO2, O3, PM10, PM2,5 and SO2); second one compares a test dataset compiled from the data from 2019, last year (2018) and a synthetic environmental (avg. 2013-2018) data set in the validation process; and the third one compares a combination of lag from 0 to 12. All the predictions are made using ARIMA algorithm. The evaluation is given in terms of MAE, MSE, RMSE, OR. The training set is from 2 Jun 2013 (week 22/2013) to 28 May 2018 (week 21/2018), and test set is from (week 22/2018) to (week 21/2019) with a window of predictions of 52 weeks. Results: The increment of dimensionality in the environmental variable selection introduce different noise levels and optimize the prediction. Considerations that impact the explainability, usability, ecological bias and performance will be described. Conclusion: The increment of dimensionality in the variable selection has a better impact on performance than using complex algorithms.
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The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

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Imagen de apoyo de  Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of  TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

Por: Ingrid Lizeth Lizarazo Rodríguez | Fecha: 2021

Abstract: Biological and physiological changes in response to stress are crucial to achieving adaption to environmental constraints. Typical stress responses activate the sympathetic nervous system and the hypothalamic-pituitary-adrenal cortical axis, which aim to maintain homeostasis in response to demands and influence various biological responses at neuroendocrine, cellular, and immune levels. In particular, there is compelling evidence showing the devastating effects of high-stress levels on immune responses and brain functionality. In that sense, data suggest that a sustained stress-physiological response predicts decreases in immunity and leads to allostatic load, the wear, and tear of biological systems. Similarly, in cancer research, chronic stress levels have been reported to impair the bodysurveillance systems and be related to cancer incidence, progression, and mortality. Despite the evidence demonstrating the associations between stress and cancer, there are limited data on whether lifetime stress exposure relates to clinical indicators of cancer aggressiveness. Considering the evidence showing the adverse effects of prolonged stress exposure on cancer disease, this thesis aimed to explore the relationship between lifetime stress exposure and the clinical characteristics of tumor-aggressiveness in a cohort of patients affected with triple-negative breast cancer (TNBC). Likewise, as research has shown that coping responses moderate the stress-physiological response, we aimed to investigate the role of coping responses in moderating the association between tumor aggressiveness and lifetime stress exposure. According to the scientific literature, high-stress levels would increase physiological arousal and allostatic load favoring a debilitated immune system. Thus, we hypothesized finding positive associations between lifetime stress exposure and tumor-aggressiveness. In the same line, we suspected that adaptative coping styles would be negatively related to tumoraggressiveness. The participants of this study were 29 women diagnosed with TNBC who were treated in the University Hospital for Gynecology Pius-Hospital (Oldenburg, Germany). Correlation and moderation regression analyses with the use of composite scores were conducted. Overall, we could not demonstrate significant associations between lifetime stress exposure and coping responses on the clinical indicators of tumor aggressiveness in this cohort of patients. Possible explanations for these results are discussed, and suggestions for future research are provided. This study was the first to investigate the effect of lifetime stress exposure and coping response on the aggressive tumor characteristics of TNBC. We provided a deep theoretical framework to understand the interplay between biological and psychological aspects of cancer disease, and we hope that our recommendations may serve as a base for upcoming studies.
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Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

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Imagen de apoyo de  Involvement of LRP5 in cardiovascular diseases = Implicación de LRP5 en la enfermedad cardiovascular

Involvement of LRP5 in cardiovascular diseases = Implicación de LRP5 en la enfermedad cardiovascular

Por: July Carolina Romero Sandoval | Fecha: 2014

Las enfermedades cardiovasculares (CVD) son la primera causa de discapacidad y muerte prematura en el mundo. La aterosclerosis, caracterizada por la acumulación de lípidos y elementos fibrosos en las arterias, es el principal proceso patológico que da lugar a las CVD. En el desarrollo de esta patología participan la diferenciación, la proliferación y la migración celular, dando lugar a diferentes respuestas celulares y moleculares, que son características de una enfermedad inflamatoria. La vía de señalización por Wnt es un regulador de la proliferación, la supervivencia y la diferenciación celular y es una de las primeras repuestas celulares al daño. En esta tesis quisimos discernir si la vía canónica de señalización por Wnt tiene un papel anti- o pro-inflamatorio durante la progresión de la lesión aterosclerótica, así como la implicación de su activación mediante LRP5 en los estados iniciales de la aterosclerosis. Con este fin, analizamos la expresión de LRP5 en los tipos celulares implicados en la formación de la lesión aterosclerótica y su modulación por los lípidos extracelulares. Estudiamos la implicación del LRP5 en la diferenciación y proliferación de las células inflamatorias que participan en la formación de la lesión aterosclerótica y caracterizamos la función de LRP5 y la vía canónica de señalización por Wnt en un modelo de ratones hipercolesterolémicos deficientes para LRP5. Nuestros resultados demuestran que los lípidos extracelulares aumentan la expresión de LRP5 en cultivos de macrófagos humanos provocando la activación de la vía de de señalización por Wnt, mientras que el silenciamiento de LRP5 provoca una menor migración de los macrófagos. La sobreexpresión de LRP5 en monocitos induce una menor diferenciación a macrófagos, una disminución de la proliferación y un aumento de la apoptosis. En ratones hipercolesterolémicos deficientes para LRP5 la vía canónica de señalización por Wnt se encuentra bloqueada empeorando el perfil dislipémico de los ratones Lrp5-/- mediante el aumento de la infiltración de monocitos en la pared vascular y de la respuesta inflamatoria de los leucocitos. Además, demostramos que los efectos proaterogénicos ocasionados por el exceso de lípidos en el plasma están mediamos en parte por la modulación de la expresión de LRP5 en la aorta y que LRP5 y la vía canónica de señalización por Wnt ejercen un mecanismo de defensa contra de la hiperlipidemia y la progresión de las lesiones ateroscleróticas. Así, este trabajo describe la implicación de LRP5 en diferentes procesos celulares claves durante la formación de la lesión, como son la infiltración y diferenciación de las células monocíticas, la adhesión y migración celular y la captación de lípidos. Además, demostramos que la ausencia de este receptor durante la hipercolesterolemia ocasiona una deficiencia en la respuesta inflamatoria y en el metabolismo de las lipoproteínas a nivel sistémico. En conjunto, nuestros resultados demuestran la participación de LRP5 en el desarrollo de la lesión aterosclerótica y evidencian un papel ateroprotector y de supervivencia para LRP5 y la vía canónica de señalización por Wnt.
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Involvement of LRP5 in cardiovascular diseases = Implicación de LRP5 en la enfermedad cardiovascular

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Imagen de apoyo de  Approximal caries: Prevalence and progression rate in Young Danish adults and an innovative non-operative approach for lesions around the EDJ

Approximal caries: Prevalence and progression rate in Young Danish adults and an innovative non-operative approach for lesions around the EDJ

Por: Stefania Martignon | Fecha: 2005

A literature review disclosed that even under very strict caries preventive control, in young Swedish people many initial approximal lesions slowly progress. A study was performed to investigate if the same trend could be seen in young Danish adults. In 1996 a group of Danish military conscripts were investigated clinically and radiographically. Based on the radiographs, one lesion with radiolucency up to one third in the dentine was randomly selected from each conscript. Contact was established with these former conscripts in 2002 and radiographs taken around 2002 were used to investigate the state of the selected lesions in terms of regression, stabilization or progression. It was observed that about 60% of the selected lesions had progressed during the 5 to 6 year period. Therefore there was a need to look for other preventive measures than those traditionally used in a Danish context, such as instructions in flossing and local application of fluoride. Looking through the literature, it was realized that sealing of occlusal lesions was highly effective but this procedure was not used on approximal surfaces. The next step was to investigate if it was technically possible to seal approximal lesions and if so what material should be used. A laboratory study was conducted in which 6 dental materials were compared in relation to: their handling, presence at the surface of the lesion, and ability to penetrate into a lesion. Based on that study Gluma One Bond® (Heraeus Kulzer) was selected to be used in further studies. The final step was an 18-month clinical investigation to evaluate the effect of sealing approximal lesions. About 80 young adults from Denmark and Colombia participated in this investigation; each had at least 2 initial approximal lesions. One lesion was selected for sealing; the other one acted as control. Baseline radiographs were taken by means of special equipment so new radiographs could be taken in the same position after 18 months. The sealing procedure was performed in accordance with the guideline designed in the laboratory study. The patient was instructed to floss all sealed and non-sealed approximal lesions. Radiographs were used to assess caries progression in the test and control lesions in three ways: by comparing baseline with final scoring of the lesions on the individual conventional radiographs, by reading the conventional radiographs as pairs and finally using subtraction radiography of digitized images. The examiner was blind to lesion type (test or control) for all comparisons and also blind to whether radiographs were baseline or follow up in the case of examinations of the single radiographs and paired comparison. Repeat assessment of the radiographs was conducted on 20% of the radiographs and the subtraction images. For the paired comparison of radiographs and subtraction radiography assessment significantly more control lesions progressed (47.2%; 85%) than test lesions (22.2%; 43%) (P-values<0.05). For the independent examination of the radiographs a similar pattern was seen but the difference between the two groups was not statistically significant (P=0.06). In conclusion, many approximal lesions seemed to progress on young adults irrespective of the preventive regime they were advised to take. This study has developed and investigated a technique for sealing early approximal lesions which seems to be more effective at preventing lesion progression than conventional interventions such as brushing and flossing. There is a need however, for defining more precisely criteria at selecting lesions to be sealed; for developing better materials in terms of better penetration skill and that they stay there, and for clinical investigations which evaluate the long term effect of sealing the approximal lesions.
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Approximal caries: Prevalence and progression rate in Young Danish adults and an innovative non-operative approach for lesions around the EDJ

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Imagen de apoyo de  Establishment of a suitable model for the further study of mechanisms affecting autophagy of aged insulin SGs = Diseño de un modelo que permita estudiar el mecanismo que afecta el proceso de autofagia de los gránulos de insulina que han envejecido

Establishment of a suitable model for the further study of mechanisms affecting autophagy of aged insulin SGs = Diseño de un modelo que permita estudiar el mecanismo que afecta el proceso de autofagia de los gránulos de insulina que han envejecido

Por: Andrés Felipe Soto López | Fecha: 2016

Insulin hormone is produced by pancreatic beta-cells and its biosynthesis, secretion, and intracellular degradation is tightly regulated. Newly formed SGs are preferentially released upon glucose stimulation while aged SGs are less competitive to be released and are more prompt to degradation mainly within lysosomes. The most assumed mechanism leading aged SGs to lysosome is autophagy, a degradation system for altered proteins and damaged organelles. The autophagic marker LC3 has facilitated the detection of autophagy through LC3-based biochemical and microscopic assays, as well as the possibility to experimentally manipulate the autophagy pathway. Here, we intended to establish a model for the further study of mechanism that target aged Ins-SNAPTMR-Star+ SGs to GFP-LC3+ autophagosomes in INS-1 cells by using three different approaches. Our results show that in INS-1 cells, modulation of autophagy with chemical agents can be detected by western blot. Likewise, TIRF Microscopy allowed for the detection of positive GFP-LC3+ aged Ins-SNAPTMR-Star+ objects in the cortical region of INS-1 cells. Additionally, we implemented SIM microscopy to gain more detail in the morphological aspect of autophagosomes vesicles. Despite some hints about the autophagosomal structures were uncovered through these approaches, further experiments should be performed to complement and confirm our findings. Thus, establishment of a suitable model for the study of autophagy, will allow us to further study the mechanisms behind the targeting process of aged SGs and to better understand how impairment of autophagy contributes to deterioration of pancreatic beta-cell function and subsequent onset of type 2 diabetes.
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Establishment of a suitable model for the further study of mechanisms affecting autophagy of aged insulin SGs = Diseño de un modelo que permita estudiar el mecanismo que afecta el proceso de autofagia de los gránulos de insulina que han envejecido

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Imagen de apoyo de  Fluorescence staining as a detection method of indicators and pathogens in aerobic granular sludge. A study with Escherichia coli and Cryptosporidium parvum = Tinción fluorescente como método de detección de indicador y patógenos en lodo granular aerobio. Un estudio con Escherichia coli y Cryptosporidium parvum

Fluorescence staining as a detection method of indicators and pathogens in aerobic granular sludge. A study with Escherichia coli and Cryptosporidium parvum = Tinción fluorescente como método de detección de indicador y patógenos en lodo granular aerobio. Un estudio con Escherichia coli y Cryptosporidium parvum

Por: María Clara Vanegas Camero | Fecha: 2018

Waterborne diseases are transmitted by the faecal-oral route when water contaminated with faeces is ingested. Cryptosporidiosis is one of these diseases and is caused by one of the most widespread enteric parasites in the world; Cryptosporidium. To reduce the waterborne diseases, domestic wastewater needs to be treated sufficiently to reduce its pathogenic content. One of the recently introduced technologies for wastewater treatment is Aerobic Granular Sludge (AGS). AGS has proven to produce effluents with high chemical quality standards. However, little is known regarding the pathogen removal efficiencies or their removal mechanisms. In addition, there is a worldwide need to treat domestic wastewater appropriately to reduce pathogens causing waterborne diseases. The removal efficiencies and fate of some pathogens, such as Cryptosporidium, have not been studied in detail within wastewater treatment processes. Indicator microorganisms such as Escherichia coli (E. coli), have been used to understand the removal mechanisms and fate of pathogens in wastewater. However, it was found there is a miscorrelation between indicators and pathogens, and therefore there is a need for studies with pathogens themselves. Due to these reasons, this research aimed to develop a fluorescent staining method for E. coli and Cryptosporidium parvum (C. parvum) oocysts to allow their detection in AGS batch reactors, and evaluate the fate of fluorescently stained E. coli and C. parvum in these reactors. Pre-staining of E. coli and C. parvum was carried out using two fluorescent stains: dsGreen and SYBR. Experiments were carried out to test different pre-staining conditions. The stains were serial diluted, TWEEN was used to determine if it improved the staining, and the prestained microorganisms were incubated at 4 ºC, room temperature and 37 ºC. Two different batch reactors, 250 mL and 2 mL, were set up with AGS and were spiked with pre-stained microorganisms. Both reactors were run for 120 mins and sludge samples were collected and analysed using fluorescent microscopy. The filtered supernatant samples from the 250 mL were also analysed using the fluorescent microscope and the fluorescent cell count method. The best staining conditions for E. coli and C. parvum oocysts with dsGreen proved to be: 1,000x dilution of dye, incubation of stained microorganisms at room temperature for 15 mins and no need of TWEEN. SYBR photobleached rapidly and was therefore not an appropriate stain for this research. With the experiments in batch reactors, the fluorescent cell count method proved to be a generic and faster quantitative alternative to estimate E. coli concentrations in filtered supernatant samples than the E. coli agar plate method. In addition, it was qualitatively confirmed that fluorescently stained E. coli was removed by the predation of different species of protozoa. However, no conclusive results regarding protozoan predation of C. parvum oocysts were observed. Resumen: Las enfermedades transmitidas por el agua se transmiten por la ruta fecal-oral cuando se ingiere agua contaminada con heces. La criptosporidiosis es una de estas enfermedades y es causada por uno de los parásitos entéricos más extendidos del mundo; Cryptosporidium. Para reducir las enfermedades transmitidas por el agua, las aguas residuales domésticas deben tratarse lo suficiente como para reducir su contenido patógeno. Una de las tecnologías recientemente introducidas para el tratamiento de aguas residuales es el lodo granular aeróbico (AGS por sus siglas en inglés). AGS ha demostrado producir efluentes con altos estándares de calidad química. Sin embargo, se sabe poco sobre las eficiencias de eliminación de patógenos o sus mecanismos de eliminación. Además, existe una necesidad mundial de tratar las aguas residuales domésticas de manera adecuada para reducir los patógenos que causan enfermedades transmitidas por el agua. Las eficiencias de eliminación y el destino de algunos patógenos, como el Cryptosporidium, no se han estudiado en detalle en los procesos de tratamiento de aguas residuales. Se han utilizado microorganismos indicadores como Escherichia coli (E. coli) para comprender los mecanismos de eliminación y el destino de los patógenos en las aguas residuales. Sin embargo, se descubrió que existe una mala correlación entre los indicadores y los agentes patógenos y, por lo tanto, es necesario realizar estudios con los mismos agentes patógenos. Debido a estas razones, esta investigación tuvo como objetivo desarrollar un método de tinción fluorescente para E. coli y ooquistes de Cryptosporidium parvum (C. parvum) para permitir su detección en reactores discontinuos de AGS, y evaluar el destino de E. coli y C. parvum teñidos con fluorescencia en estos reactores. La tinción previa de E. coli y C. parvum se llevó a cabo utilizando dos tinciones fluorescentes: dsGreen y SYBR. Se llevaron a cabo experimentos para probar diferentes condiciones de pre-tinción. Las tintas se diluyeron en serie, se utilizó TWEEN para determinar si mejoraba la tinción, y los microorganismos pre-teñidos se incubaron a 4 ºC, temperatura ambiente y 37 ºC. Se prepararon dos reactores discontinuos diferentes, 250 ml y 2 ml, con AGS y se añadieron microorganismos previamente teñidos. Ambos reactores funcionaron durante 120 minutos y las muestras de lodo se recogieron y analizaron usando microscopía fluorescente. Las muestras de sobrenadante filtradas de 250 ml también se analizaron utilizando el microscopio fluorescente y el método de recuento de células fluorescentes. Las mejores condiciones de tinción para la E. coli y los ooquistes de C. parvum con dsGreen demostraron ser: dilución de colorante a 1,000x, incubación de microorganismos teñidos a temperatura ambiente durante 15 minutos y sin necesidad de TWEEN. SYBR se blanqueó rápidamente y, por lo tanto, no fue una tinta adecuada para esta investigación. Con los experimentos en reactores discontinuos, el método de recuento de células fluorescentes demostró ser una alternativa cuantitativa genérica y más rápida para estimar las concentraciones de E. coli en muestras de sobrenadante filtradas que el método de la placa de agar de E. coli. Además, se confirmó cualitativamente que E. coli teñida con fluorescencia se removió por la predación de diferentes especies de protozoos. Sin embargo, no se observaron resultados concluyentes con respecto a la predación de protozoos de los ooquistes de C. parvum.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Fluorescence staining as a detection method of indicators and pathogens in aerobic granular sludge. A study with Escherichia coli and Cryptosporidium parvum = Tinción fluorescente como método de detección de indicador y patógenos en lodo granular aerobio. Un estudio con Escherichia coli y Cryptosporidium parvum

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The effect of abortion legalization on child and maternal health in Mexico City = El efecto de la legalización del aborto en la salud materno infantil en Ciudad de México

Por: Tatiana Castillo Betancourt | Fecha: 2017

In 2007, Mexico City legalized abortion in the first 12 weeks of pregnancy. By doing so, it became the first and only state in Mexico where abortion on demand is legal. In this paper, I use this natural experiment to estimate the effects of abortion legalization on child and maternal health. I perform Difference-In-Differences estimates using information from all births and deaths occurred between 2002 and 2012. My findings suggest that the change in the abortion legislation in Mexico City reduced the Infant Mortality Rate and the Under 5 Mortality Rate by approximately 2.3 and 2.4 deaths per 1,000 live births, respectively. Moreover, for the Maternal Mortality Rate I find that the estimations range from -5.49 to -6 deaths per 100,000 live births. These results are validated by the use of a more accurate control group generated by the Synthetic Control Method. To the best of my knowledge, this if the first paper that attempts to examine the effects of abortion legalization in Mexico City on child health. En el 2007, Ciudad de México legalizó el aborto en las 12 primeras semanas de gestación. Al hacerlo, se convirtió en el primero y único estado del país en donde el aborto voluntario es legal. En este artículo utilizo este experimento natural para estimar los efectos de la legalización del aborto en la salud materno infantil. Realizo estimaciones de Diferencias en Diferencias utilizando información de todos los nacimientos y muertes ocurridos entre 2002 y 2012. Mis hallazgos sugieren que el cambio en la legislación relativa el aborto en la Ciudad de México redujo la tasa de mortalidad Infantil y la tasa de mortalidad en menores de 5 años en aproximadamente 2.3 y 2.4 muertes por cada 1.000 nacidos vivos, respectivamente. Además, para la tasa de mortalidad materna, encuentro que las estimaciones oscilan entre -5,49 y -6 muertes por 100.000 nacidos vivos. Estos resultados se validan mediante el uso de un grupo de control más preciso, utilizando la metodología de control sintético. Según mi conocimiento, este es el primer artículo que intenta examinar los efectos de la legalización del aborto en la Ciudad de México sobre la salud infantil.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
  • Temas:
  • Otros
  • Medicina

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The effect of abortion legalization on child and maternal health in Mexico City = El efecto de la legalización del aborto en la salud materno infantil en Ciudad de México

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