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1.
Medicina (B Aires) ; 84(1): 29-46, 2024.
Artículo en Español | MEDLINE | ID: mdl-38271930

RESUMEN

INTRODUCTION: The objective of this study was to analyze the geographic variability and the relationship between social determinants of health and COVID-19 lethality in Bariloche. METHODS: A database from the National Epidemiological Surveillance System was used to analyze COVID-19 positive cases from January 2020 to December 2021. The data were geocoded and incorporated into a geographic information system (GIS). A three-step analytical framework was applied to measure health inequity, using socioeconomic indicators and access to services. A multivariate analysis was conducted to predict fatality. RESULTS: A total of 25 020 COVID-19 cases were diagnosed in Bariloche during the study period. The fatality rate was 2.1%. Significant variability in socioeconomic indicators was observed among different territorial delegations of the city. DISCUSSION: The results showed health inequities and an association between social determinants and COVID-19 lethality in Bariloche. Individuals living in areas with higher socioeconomic vulnerability had a higher risk of mortality. These findings highlight the importance of addressing health inequities in a pandemic response.


Introducción: El objetivo de este estudio fue examinar cómo la variabilidad geográfica y los determinantes sociales de la salud influyen en la tasa de letalidad por COVID-19 en Bariloche. Métodos: Se utilizó una base de datos del Sistema Nacional de Vigilancia Epidemiológica para analizar los casos positivos de COVID-19 desde enero de 2020 hasta diciembre de 2021. Los datos se geo-codificaron y se incorporaron en un sistema de información geográfica (SIG). Se aplicó un marco de análisis en tres pasos para medir la inequidad en salud, utilizando indicadores socioeconómicos y de acceso a servicios. Se realizó un análisis multivariado para predecir la letalidad. Resultados: Se diagnosticaron un total de 25 020 casos de COVID-19 en Bariloche durante el período de estudio. La letalidad fue del 2.1%. Se observó una variabilidad significativa en indicadores socioeconómicos entre las diferentes delegaciones territoriales de la ciudad. Discusión: Los resultados mostraron inequidades en salud y una asociación entre determinantes sociales y letalidad por COVID-19 en Bariloche. Las personas que vivían en áreas con mayor vulnerabilidad socioeconómica presentaron un mayor riesgo de mortalidad. Estos hallazgos resaltan la importancia de abordar las inequidades en salud en la respuesta a una pandemia.


Asunto(s)
COVID-19 , Inequidades en Salud , Humanos , COVID-19/mortalidad , Análisis Multivariante , Factores Socioeconómicos , Argentina/epidemiología
2.
Environ Sci Pollut Res Int ; 30(3): 6466-6491, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35997874

RESUMEN

Biosurfactants are molecules with wide application in several industrial processes. Their production is damaged due to inefficient bioprocessing and expensive substrates. The latest developments of strategies to improve and economize the biosurfactant production process use alternative substrates, optimization techniques, and different scales. This paper presents a study to compare the performances of classical (polynomial models) and modern tools, such as artificial intelligence to aid optimization of the alternative substrate concentration (alternative based on beet peel and glycerol) and process parameters (agitation and aeration). The evaluation was developed in two different scales: Erlenmeyer flask (100 mL) and bioreactor (7 L). The intelligent models were implemented to verify the ability to predict the emulsification index and biosurfactant concentration in smaller scale and the biosurfactant concentration and the superficial tension reduction (STR) in bigger scale, resulting in four different situations. The overall results of the predictions led to artificial neural networks as the best performing modeling tool in all four situations studied, with R2 values ranging from 0.9609 to 0.9974 and error indices close to 0. Also, four different models (Wu, Contois, Megee, and Ghose-Tyagi) were adjusted by particle swarm optimization (PSO) in order to describe the kinetics of biosurfactant production. Contois model was the only one to present R2 ≥ 0.97 for all monitored variables. The findings described in this work present an adjusted model for the prediction of biosurfactant production and also state that the most adjusted kinetic model for further studies on this process is Contois model, leading to the conclusion that biomass growth is limited by a single substrate, considering only glucose.


Asunto(s)
Inteligencia Artificial , Tensoactivos , Tensoactivos/química , Modelos Estadísticos , Redes Neurales de la Computación , Reactores Biológicos
3.
Curr Biol ; 30(24): R1500-R1510, 2020 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-33352137

RESUMEN

The United Nations General Assembly calls for ecosystem restoration to be a primary intervention strategy used to counter the continued loss of natural habitats worldwide, while supporting human health and wellbeing globally. Restoration of coastal marine ecosystems is perceived by many to be expensive and prone to failure, in part explaining its low rates of implementation compared with terrestrial ecosystems. Yet, marine ecosystem restoration is a relatively new field, and we argue that assessments of its potential to answer this call should not rely on typical outcomes, but also to learn from successful outliers. Here, we review successful restoration efforts across a suite of metrics in coastal marine systems to highlight 'bright spots'. We find that, similar to terrestrial systems, restoration interventions can be effective over large spatial expanses (1,000s-100,000s ha), persist for decades, rapidly expand in size, be cost-effective, and generate social and economic benefits. These bright spots clearly demonstrate restoration of coastal marine systems can be used as a nature-based solution to improve biodiversity and support human health and wellbeing. Examining coastal marine restoration through a historical lens shows that it has developed over a shorter period than restoration in terrestrial systems, partially explaining lower efficiencies. Given these bright spots and the relative immaturity of coastal marine ecosystem restoration, it is likely to advance rapidly over the coming decades and become a common intervention strategy that can reverse marine degradation, contribute to local economies, and improve human wellbeing at a scale relevant to addressing global threats.


Asunto(s)
Ecosistema , Restauración y Remediación Ambiental/métodos , Salud Global , Océanos y Mares , Humanos
4.
Philos Trans R Soc Lond B Biol Sci ; 370(1681)2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26460131

RESUMEN

Models provide useful insights into conservation and resource management issues and solutions. Their use to date has highlighted conditions under which no-take marine protected areas (MPAs) may help us to achieve the goals of ecosystem-based management by reducing pressures, and where they might fail to achieve desired goals. For example, static reserve designs are unlikely to achieve desired objectives when applied to mobile species or when compromised by climate-related ecosystem restructuring and range shifts. Modelling tools allow planners to explore a range of options, such as basing MPAs on the presence of dynamic oceanic features, and to evaluate the potential future impacts of alternative interventions compared with 'no-action' counterfactuals, under a range of environmental and development scenarios. The modelling environment allows the analyst to test if indicators and management strategies are robust to uncertainties in how the ecosystem (and the broader human-ecosystem combination) operates, including the direct and indirect ecological effects of protection. Moreover, modelling results can be presented at multiple spatial and temporal scales, and relative to ecological, economic and social objectives. This helps to reveal potential 'surprises', such as regime shifts, trophic cascades and bottlenecks in human responses. Using illustrative examples, this paper briefly covers the history of the use of simulation models for evaluating MPA options, and discusses their utility and limitations for informing protected area management in the marine realm.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Biología Marina , Modelos Biológicos , Animales , Clima , Arrecifes de Coral , Ecosistema , Humanos
5.
Bol. latinoam. Caribe plantas med. aromát ; 14(3): 251-262, mayo 2015. tab, ilus, graf
Artículo en Inglés | LILACS | ID: biblio-907487

RESUMEN

This search is focused on the study of diet compounds that may have any potential chemopreventive effect against cancer. Some compounds that fulfill this requirement are phytoestrogens. Among them we find genistein (1), the most studied, daidzein (2) and equol (3) (figure 1). To compare the sensitivities of different prostate cancer cells to phytoestrogen treatment, sulphorhodamine B dye assay was performed to determine cell viability. DU-145 and PC-3 prostate cancer cell lines treated with various doses of phytoestrogen (0-12.5-25-50 and 100 μM) for different times (24, 48 and 72h). For cell invasion or migration assay cells were seeded in a Transwell chamber with or without coating Matrigel respectively. DU-145 and PC-3 cells were treated previously with phytoestrogen (50 μM) for 24h. The study showed that equol, daidzein and genistein inhibited migration and invasion in prostate cancer cell lines. Moreover, we analyzed the effects of phytoestrogens in MMP-2 and MMP-9 mRNA expression by RT-PCR. The results indicated that equol, daidzein and genistein diminished the expression of MMP-2 and MMP-9 in a cell-dependent manner. Our data suggested that equol, daidzein and genistein inhibited migration and invasion in prostate cancer cell lines. Moreover, the results also suggest that down-regulation of MMP-2 and MMP- 9 might be involved in the inhibition of invasion of PC-3 and DU-145 cells after genistein, daidzein and equol treatment.


Este trabajo se centra en el estudio de los compuestos de dieta que pueden tener potencial efecto quimiopreventivo contra el cáncer. Algunos de estos compuestos son los fitoestrógenos. Entre ellos encontramos la genisteína (1), el más estudiado, la daidzeína (2) y el equol (3) (figura 1). Para comparar el efecto de estos fitoestrogenos sobre las líneas celulares de cáncer de próstata, DU-145 y PC-3, se utilizó el ensayo de sulforodamina B para determinar la viabilidad celular tras los tratamientos con diferentes concentraciones de fitoestrógenos (0-12.5-25-50-100 μM) durante diferentes tiempos (24, 48, 72 h). Para analizar el efecto sobre la migración celular, las células DU-145 y PC-3 fueron tratadas previamente con una concentración de fitoestrógrno (50 μM) durante 24 horas y sembradas en una cámara Transwell sin recubrir. El estudio mostró que el equol, daidzeína y genisteína inhibió en MMP-2 y MMP-9 expresiones de genes en líneas celulares de cáncer de próstata, la PC-3 y DU-145. Los resultados indicaron que la daidzeína disminuyó la expresión de MMP- 2 y MMP-9 en DU-145 células. Nuestros datos sugieren que equol, daidzeína y genisteína inhiben la migración y la invasión de líneas celulares de cáncer de próstata.


Asunto(s)
Equol/farmacología , Genisteína/farmacología , Isoflavonas/farmacología , Neoplasias de la Próstata , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Dieta , Inhibidores de la Metaloproteinasa de la Matriz , Invasividad Neoplásica/prevención & control , Fitoestrógenos/farmacología
6.
PLoS One ; 9(3): e91833, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24633147

RESUMEN

A theoretical basis is required for comparing key features and critical elements in wild fisheries and aquaculture supply chains under a changing climate. Here we develop a new quantitative metric that is analogous to indices used to analyse food-webs and identify key species. The Supply Chain Index (SCI) identifies critical elements as those elements with large throughput rates, as well as greater connectivity. The sum of the scores for a supply chain provides a single metric that roughly captures both the resilience and connectedness of a supply chain. Standardised scores can facilitate cross-comparisons both under current conditions as well as under a changing climate. Identification of key elements along the supply chain may assist in informing adaptation strategies to reduce anticipated future risks posed by climate change. The SCI also provides information on the relative stability of different supply chains based on whether there is a fairly even spread in the individual scores of the top few key elements, compared with a more critical dependence on a few key individual supply chain elements. We use as a case study the Australian southern rock lobster Jasus edwardsii fishery, which is challenged by a number of climate change drivers such as impacts on recruitment and growth due to changes in large-scale and local oceanographic features. The SCI identifies airports, processors and Chinese consumers as the key elements in the lobster supply chain that merit attention to enhance stability and potentially enable growth. We also apply the index to an additional four real-world Australian commercial fishery and two aquaculture industry supply chains to highlight the utility of a systematic method for describing supply chains. Overall, our simple methodological approach to empirically-based supply chain research provides an objective method for comparing the resilience of supply chains and highlighting components that may be critical.


Asunto(s)
Abastecimiento de Alimentos , Modelos Teóricos , Alimentos Marinos/provisión & distribución , Algoritmos , Animales , Humanos
7.
Adv Mar Biol ; 66: 213-90, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24182902

RESUMEN

The Coral Sea, located at the southwestern rim of the Pacific Ocean, is the only tropical marginal sea where human impacts remain relatively minor. Patterns and processes identified within the region have global relevance as a baseline for understanding impacts in more disturbed tropical locations. Despite 70 years of documented research, the Coral Sea has been relatively neglected, with a slower rate of increase in publications over the past 20 years than total marine research globally. We review current knowledge of the Coral Sea to provide an overview of regional geology, oceanography, ecology and fisheries. Interactions between physical features and biological assemblages influence ecological processes and the direction and strength of connectivity among Coral Sea ecosystems. To inform management effectively, we will need to fill some major knowledge gaps, including geographic gaps in sampling and a lack of integration of research themes, which hinder the understanding of most ecosystem processes.


Asunto(s)
Antozoos/fisiología , Biodiversidad , Océanos y Mares , Animales , Cambio Climático , Demografía , Cadena Alimentaria , Actividades Humanas , Humanos , Contaminación del Agua
9.
J Med Food ; 15(12): 1081-90, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23216111

RESUMEN

Sex hormone replacement therapy provides several advantages in the quality of life for climacteric women. However, estrogen-induced cell proliferation in the uterus and mammary gland increases the risk of cancer development in these organs. The lower incidence of mammary cancer in Asian women as compared with Western women has been attributed to high intake of soy isoflavones, including genistein. We have previously shown that genistein induces an estradiol-like hypertrophy of uterine cells, but does not induce cell proliferation, uterine eosinophilia, or endometrial edema. It also inhibits estradiol-induced mitosis in uterine cells and hormone-induced uterine eosinophilia and endometrial edema. Nevertheless, genistein stimulates growth of human breast cancer cells in culture; therefore, it is not an ideal estrogen for use in hormone replacement therapy (HRD). The present study investigated the effect of another soy isoflavone, daidzein (subcutaneous, 0.066 mg/kg body weight), in the same animal model, and its effect on responses induced by subsequent treatment (1 h later) with estradiol-17ß (E(2); subcutaneous, 0.33 mg/kg body weight). In addition, we investigated the effects of daidzein (1 µg/mL) or E(2) on the growth of human breast cancer cells in culture. Results indicate that daidzein stimulates growth of breast cancer cells and potentiates estrogen-induced cell proliferation in the uterus. We suggest caution for the use of daidzein or formulas containing this compound in HRD. Future research strategies should be addressed in the search for new phytoestrogens that selectively inhibit cell proliferation in the uterus and breast.


Asunto(s)
Estrógenos/farmacología , Isoflavonas/farmacología , Útero/efectos de los fármacos , Animales , Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Interacciones Farmacológicas , Estradiol/farmacología , Femenino , Humanos , Células MCF-7 , Fitoestrógenos/farmacología , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley , Útero/metabolismo
10.
J Med Food ; 14(12): 1597-603, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21612459

RESUMEN

Sex hormone replacement therapy helps improve quality of life in climacteric women. However, estrogen-induced cell proliferation in the uterus and mammary gland increases the risk for cancer in these organs. The lower incidence of mammary cancer in Asian women than in western women has been attributed to high intake of soy isoflavones, including genistein. Our previous work in the prepubertal rat uterus model showed that genistein (0.5 mg/kg body weight subcutaneously) caused an estradiol-like hypertrophy in myometrial and uterine luminal epithelial cells and an increase in RNA content in luminal epithelium; however, it did not induce cell proliferation, uterine eosinophilia, or endometrial edema. The present study investigated, in the same animal model, the effect of genistein administration (0.5 mg/kg body weight subcutaneously) before treatment with estradiol-17ß (0.33 mg/kg body weight subcutaneously) on uterine responses that were not induced by genistein. Pretreatment with this phytoestrogen completely inhibited estradiol-induced mitoses in uterine luminal epithelium, endometrial stroma, and myometrium and partially inhibited estradiol-induced uterine eosinophilia and endometrial edema. These findings indicate that genistein protects against estrogen-induced cell proliferation in the uterus and suggest that future studies should investigate the possibility of using this agent to decrease the risk for uterine cancer after hormone replacement therapy in climacteric women.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Estrógenos/farmacología , Genisteína/administración & dosificación , Fitoestrógenos/administración & dosificación , Útero/efectos de los fármacos , Animales , Anticarcinógenos/administración & dosificación , Endometrio/efectos de los fármacos , Epitelio/efectos de los fármacos , Estradiol/farmacología , Femenino , Hormonas/metabolismo , Isoflavonas/administración & dosificación , Menopausia/efectos de los fármacos , Miometrio/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factores de Riesgo , Útero/metabolismo , beta-Glucanos/administración & dosificación
11.
ISRN Obstet Gynecol ; 2011: 329692, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22263113

RESUMEN

Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and experimental animals and causes infertility and other adverse effects. The present paper investigated the effects of prenatal exposure to lead on different parameters of estrogen stimulation in the uterus of the prepubertal rat. In prenatally and perinatally exposed rats, estrogen-induced endometrial eosinophilia, endometrial stroma edema, and eosinophil migration towards the endometrium, and uterine luminal epithelial hypertrophy are enhanced while several other responses to estrogen appear unchanged. These effects may contribute to decrease in fertility following prenatal exposure to lead. The striking difference between most of these effects of prenatal exposure and the previously reported effects of chronic exposure to lead suggests that prenatal exposure to lead may neutralize the effects of chronic exposure to lead, providing partial protection of cell function against the adverse effects of chronic exposure to lead. We propose that the mechanism involved, named imprinting or cell programming, persisted through evolution as a nongenetic adaptive mechanism to provide protection against long-term environmental variations that otherwise may cause the extinction of species not displaying this kind of adaptation.

12.
Artículo en Inglés | LILACS | ID: lil-613285

RESUMEN

The existence of multiple kinds of estrogen receptors (ERs), involved in independent groups of responses, allows their dissociation and opens the possibility to selectively induce beneficial responses but not those considered at risk (cell proliferation). Based on the low hormone-dependent cancer mortality in Eastern Asia, attributed to high dietary intake of estrogenic isoflavones, we investigated whether genistein (G) or soybean extracts (S) selectively induce some, but not all estrogenic responses in the rat uterus, comparing its activity to that of estradiol-17 (E2). Prepubertal rats were treated with E2, G, concentrated S (Sc), diluted S (Sd), or vehicle, and uterine responses to estrogen were evaluated. Luminal epithelial and myometrial cell hypertrophy, and luminal epithelial RNA increase, were induced by E2, G or S. Uterine eosinophilia, endometrial edema and proliferation of 4 uterine cell-types were induced by E2 only. Results reveal that G and S induce some responses to estrogen but not others, suggesting their use as agents not displaying carcinogenic risk.


La existencia de múltiples tipos de receptores de estrógeno (ERs), involucrados en el desarrollo de grupos independientes de respuestas a estrógeno, permite su disociación y abre la posibilidad de inducir en forma selectiva respuestas benéficas pero no aquellas consideradas de riesgo (proliferación celular). Basado en la baja mortalidad por cánceres hormono-dependientes en el Este Asiático, atribuidos a una alta ingesta dietaria de isoflavonas estrogénicas, nosotros investigamos si la genisteína (G) o extractos de soja (S) inducen en forma selectiva algunas, pero no todas, las respuestas estrogénicas en el útero de rata, comparando su actividad con la del estradiol-17beta (E2). Ratas prepuberales fueron tratadas con E2, G, S concentrado (Sc), S diluido (Sd) o vehículo, y las respuestas estrogénicas en el útero fueron evaluadas. Las hipertrofias celulares en epitelio luminal y miometrio, y el aumento de ARN en células del epitelio luminal fueron inducidas por E2, G o S. La eosinofilia uterina, el edema en estroma endometrial y la proliferación de 4 tipos celulares uterinos fueron inducidos sólo por E2. Los resultados revelan que G y S inducen algunas respuestas estrogénicas pero no otras, sugiriendo su uso terapéutico como agentes estrogénicos que no presentan riesgo de cáncer.


Asunto(s)
Animales , Femenino , Ratas , Fitoestrógenos/farmacología , Genisteína/farmacología , Soja/química , Útero , Estradiol/farmacología , Preparaciones de Plantas , Ratas Sprague-Dawley
14.
Cuad. méd.-soc. (Santiago de Chile) ; 49(4): 254-265, dic. 2009.
Artículo en Español | LILACS | ID: lil-547403

RESUMEN

El uso de drogas de abuso es un grave problema de salud y problema social en todo el mundo. Se conocen muy bien los efectos en salud de la exposición aguda o crónica a drogas de abuso. También que causan efectos directos en la placenta o en órganos en desarrollo de los embriones, causando malformaciones congénitas. Existe sin embargo muy poca información sobre efectos diferidos de la exposición a estos agentes durante las últimas etapas del desarrollo fetal o las primeras etapas de desarrollo postnatal.Estos agentes causan alteraciones irreversibles en la diferenciación y programación celular, que pueden ser consideradas como malformaciones bioquímicas y funcionales, responsables de alteraciones funcionales orgánicas o neuroconductuales que favorecenel desarrollo de enfermedades más tarde en la vida. En el presente trabajo se describen los efectos persistentes de la exposición a drogas de abuso ilícitas (opiáceos, cocaína, ketamina, tolueno, cannabinoides y anfetamina y sus derivados) y a drogas de abusolegalmente permitidas (alcohol etílico - nicotina y consumo de tabaco no se describen por formar parte de publicación previa en Cuadernos). Exposición a estos agentes favorece el desarrollo de una serie de enfermedades y alteraciones de la conducta más tarde en la vida. Además, se presenta evidencia que la exposición prenatal a varios químicos (plomo, el plaguicida malatión, bisfenol) y a varias drogas de abuso (opioides, etanol, cannabinoides) determinan cambios persistentes que favorecen el desarrollo de adicciones a drogas de abuso más tarde en la vida. Se concluye que, además de los problemas sociales y de salud derivadas del uso por adultos de drogas de abuso, la exposición fetal causa cambios que determina el desarrollo de varias enfermedades más tarde en la vida, incluyendo adicción a drogas de abuso. En consecuencia, la legislación gubernamental que restrinja el acceso y uso de estas drogas...


The use of drugs of abuse is a serious health and social problem through all the world. The eff ects of acute and chronic exposure of drugs of abuse on health are well known. They also cause direct eff ects on placenta o the developing embryo organs, causing congenital malformations. There is however very scarce information on the delayed eff ects of exposure to these agents during the last stages of fetal development or the early stages of postnatal development. These agents cause irreversible alterations in cell diff erentiation and programming, that could be considered as biochemical and functional malformations, responsible of functional organic or neurobehavioral alterations that favors the development of diseases later in life. The present report describes persistent effects of prenatal exposure to illicit drugs of abuse (opiates, cocaine, ketamine, toluene, cannabinoids, and amphetamine derivates) and to legal drugs of abuse (ethyl alcohol; nicotine and tobacco smoking are not reviewed since they were analyzed in a previouspublication in Cuadernos). Exposure to these agents favors the development of a myriad of diseases and behavioral alterations later in life. In addition, evidence is presented that prenatal exposure to various chemicals (lead, the pesticide malathion, bisphenol) andseveral drugs of abuse (opioids, ethanol, cannabinoids) determine persistent changes that favor the development of addictions to drugs of abuse later in life. It is concluded that, besides the known health and social problems derived by adults use of drugs of abuse, fetal exposure causes changes that determine the development of various diseases later in life, including drug addiction.Therefore, the dictation of Governmental regulations to decrease access to and use of these drugs, including the “softest” drugs such as cannabinoids, is fundamental to protect future generations health...


Asunto(s)
Humanos , Femenino , Embarazo , Contaminantes Ambientales/efectos adversos , Efectos Tardíos de la Exposición Prenatal , Trastornos Relacionados con Sustancias/complicaciones , Compuestos Químicos/efectos adversos , Drogas Ilícitas/efectos adversos , Etanol/efectos adversos , Tabaquismo/efectos adversos
15.
Trends Ecol Evol ; 24(7): 360-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19324450

RESUMEN

Fewer protected areas exist in the pelagic ocean than any other ecosystem on Earth. Although there is increasing support for marine protected areas (MPAs) as a tool for pelagic conservation, there have also been numerous criticisms of the ecological, logistical and economic feasibility of place-based management in the dynamic pelagic environment. Here we argue that recent advances across conservation, oceanography and fisheries science provide the evidence, tools and information to address these criticisms and confirm MPAs as defensible and feasible instruments for pelagic conservation. Debate over the efficacy of protected areas relative to other conservation measures cannot be resolved without further implementation of MPAs in the pelagic ocean.


Asunto(s)
Conservación de los Recursos Naturales/legislación & jurisprudencia , Explotaciones Pesqueras/legislación & jurisprudencia , Ecosistema , Océanos y Mares
16.
Rev. chil. pediatr ; 79(4): 373-380, ago. 2008. ilus
Artículo en Español | LILACS | ID: lil-517480

RESUMEN

Background: Few information is available about uterine effects of Cadmium (Cd) exposure, where toxic agents affecting the female genital tract interact with estrogen (E) receptors, modifiying myometrial activity and the menstrual cycle, causing dysmenorrhea, infertility and spontaneous abortion. No information exists whether prenatal or early postnatal exposure may cause any gynecologic persistent adverse effect. Our finding of a second mechanism of E interaction and differences between E receptors in the various uterine cell types suggests that Cd may affect differently E interaction in each cell-type. Objective: Evaluate a possible selective effect of acute Cd exposure on E action in the uterus during prepuber age. Method: Female prepuber rats exposed to Cd 4 mg/kg and 2 hours later, treated with Estradiol-17² 0,3 mg/kg. A myometrial sample was obtained under anaesthesia 24 hours after E treatment and histologically processed for the quantification of E responses on different uterine cell-types. Results: Cd exposure potentiates E-induced uterine eosinophilia and endometrial edema and inhibits E-induced cell hypertrophy in circular myometrium and cell proliferation in luminal myometrium. Cd, in the absence of hormone stimulation, causes a slight cell hypertrophy in circular myometrium. Conclusions: Acute exposure to Cd affects differently various responses to E in the different uterine cell-types. Future studies should verify whether this effect explains Cd-induced infertility, postpubertal sex organ development and whether prenatal or early postnatal exposure to Cd induces delayed persistent effects.


Antecedentes: Existe poca información sobre efectos del cadmio (Cd) en el útero. En mujeres altera la actividad miometrial, el ciclo menstrual y causa dismenorrea, abortos espontáneos, infertilidad y mortinatos. No existe información si la exposición prenatal o postnatal temprana causa efectos ginecológicos diferidos persistentes. Los tóxicos que afectan el útero suelen interactuar con receptores de estrógeno (E). Nuestro hallazgo de un segundo mecanismo de acción de E y de diferencias entre receptores de E de los diversos tipos celulares uterinos hacen posible que el Cd interactúe con los E en forma diferente en cada tipo celular. Objetivos: Buscar un posible efecto selectivo de la exposición aguda a Cd con algunas respuestas a E en útero de rata durante la edad prepuberal. Métodos: Ratas hembra impúberes recibieron 4 mg Cd/kg p.c. y 2 h después se trataron con 0,3 mg estradiol-17(3/kg p.c; los úteros fueron obtenidos bajo anestesia a las 24 h del tratamiento con E. Los úteros se procesaron para la cuantificación de respuestas a E en cada tipo celular por separado. Resultados: La exposición a Cd incrementa la eosinofilia uterina y edema endometrial inducidos por E; inhibe las siguientes respuestas a E: hipertrofia celular en miometrio circular, proliferación celular en epitelio luminal y miometrio. En ausencia de hormona, el cadmio causa una leve hipertrofia celular en miometrio circular. Conclusiones: La exposición aguda a Cd afecta de manera diferente las respuestas a E en los diversos tipos celulares uterinos de rata prepuberal. Futuros estudios deberán verificar si este efecto explica la infertilidad causada por exposición a Cd, afecta el desarrollo postpuberal de los órganos sexuales, e investigar si la exposición prenatal o postnatal temprana induce efectos diferidos persistentes, como puede ocurrir en población infantil prenatalmente expuesta a Cd.


Asunto(s)
Animales , Femenino , Cadmio/farmacología , Cadmio/toxicidad , Enfermedades Uterinas/inducido químicamente , Receptores de Estrógenos , Análisis de Varianza , Edema/inducido químicamente , Endometrio , Endometrio/patología , Eosinofilia/inducido químicamente , Estrógenos/metabolismo , Ratas Sprague-Dawley , Útero , Útero/patología
17.
Cuad. méd.-soc. (Santiago de Chile) ; 47(4): 264-276, dic. 2007. ilus, tab
Artículo en Español | LILACS | ID: lil-589290

RESUMEN

Se describe una nueva línea de investigación que tiene como objetivo investigar principios activos presentes en especies vegetales chilenas, para identificar alguna(s) que produzcan los efectos farmacológicos deseables para su uso como terapia de reemplazo hormonal en mujeres peri o postmenopáusicas, pero que no aumenten, o incluso disminuyan, el riesgo de desarrollar cáncer mamario o endometrial. Esta posibilidad se basa en el hallazgo previo de nuestro equipo de investigadores de un nuevo tipo de receptores estrogénicos responsables de respuestas estrogénicas no genómicas y de nuestro hallazgo de diferencias entre los receptores estrogénicos citosólico-nucleares clásicos de los diferentes tipos celulares uterinos. Si existiera, como anteriormente se creía, un solo tipo de receptor de estrógenos, no sería posible el desarrollo de este nuevo fármaco estrogénico selectivo que buscamos, pues todos los receptores tendrían la misma afinidad por este agente, el que en consecuencia, induciría todas las respuestas a la estimulación estrogénica (incluyendo aquellas que deseamos prevenir, como las que presentan riesgo de desarrollo de cáncer), o que actuaría como antiestrógeno, antagonizando todas las respuestas a los estrógenos en el útero.


A new research line aimed at the investigation of active agents from Chilean plant species is described. The purpose is to indentify those agents inducing expected pharmacological effects in a hormone replacement therapy in peri- or post-menopausal women, but not increasing, or even decreasing, the risk for development of mammary or endometrial cancer. This possibility is based on previous findings from our research team of a new kind of estrogen receptors, responsible of non-genomic responses to estrogen, and our finding of differences between the classical cytosol-receptor estrogen receptors from the different uterine cell-types. If there exists one kind of estrogen receptors only in the uterus, as it was formerly accepted, then it is not possible to develop the selective estrogenic drug we search for, because all receptors would display the same affinity for this agent; therefore, it would induce all responses to estrogen stimulation (including those we wish to prevent, such as those presenting risk of cancer development), or would act as antiestrogen, antagonizing all responses to estrogen in the uterus.


Asunto(s)
Humanos , Femenino , Fitoestrógenos/uso terapéutico , Menopausia , Neoplasias Endometriales/prevención & control , Neoplasias de la Mama/prevención & control , Extractos Vegetales , Terapia de Reemplazo de Hormonas/métodos , Chile , Indios Sudamericanos , Patentes como Asunto , Investigación
18.
Rev. chil. obstet. ginecol ; 67(4): 305-308, 2002. ilus, tab
Artículo en Español | LILACS | ID: lil-342270

RESUMEN

El presente trabajo muestra la experiencia clínica en el HBLT con la aplicación de la técnica de Minilap en la esterilización quirúrgica femenina. Se realizó un total de 118 esterilizaciones quirúrgicas, de las cuales 108 (91,5 por ciento del total de casos) fueron bajo anestesia local. En la gran mayoría de los casos (96,3 por ciento) resultó ser un método muy bien tolerado. Se presentaron sólo 2 casos de lesión vesical (1,7 por ciento) que se resolvieron sin inconvenientes y con una evolución favorable


Asunto(s)
Humanos , Adulto , Femenino , Persona de Mediana Edad , Esterilización Reproductiva , Anestesia Local , Complicaciones Intraoperatorias , Paridad
19.
Rev. chil. obstet. ginecol ; 67(5): 364-367, 2002. ilus, tab
Artículo en Español | LILACS | ID: lil-627332

RESUMEN

Se presentan 3 nuevos casos de placenta percreta con invasión a vejiga ocurridos en nuestro Servicio. Uno de ellos fue diagnosticado durante el embarazo, los otros dos casos fueron hallazgos intraoperatorios. La evolución clínica de las tres pacientes fue satisfactoria.


We report three new cases of placenta previa percreta involving the urinary bladder ocurred in our service. One of them was diagnosed antepartum. The other two were found during surgery. All patient had satisfactory outcome.


Asunto(s)
Humanos , Femenino , Adulto , Placenta Accreta/patología , Placenta Previa/patología , Vejiga Urinaria/patología , Placenta Accreta/cirugía , Placenta Previa/cirugía , Vejiga Urinaria/cirugía
20.
Oecologia ; 102(2): 189-201, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-28306874

RESUMEN

The structure of rocky intertidal communities may be influenced by large-scale patterns of productivity. In this study we examine the in situ rates of production by intertidal epilithic microalgae (chlorophyll a production per unit area per month), intertidal nutrient concentrations (nitrates, nitrites, phosphates and silicates), and standing stocks of different functional-form groups of macroalgae around the South African coast, and their relationships to consumer biomass. Clear gradients of in situ intertidal primary production and nutrient concentrations were recorded around the South African coast, values being highest on the west coast, intermediate on the south and lowest on the east coast. Primary production by intertidal epilithic microalgae was correlated with nutrient availability and could also be related to nearshore phytoplankton production. The dominance patterns of different functional forms of macroalgae changed around the coast, with foliose algae prevalent on the west coast and coralline algae on the east coast. However, overall macroalgal standing stocks did not reflect the productivity gradient, being equally high on the east and west coasts, and low in the south. Positive relationships existed between the average biomass of intertidal intertebrate consumers (grazers and filter-feeders) and intertidal productivity, although only the grazers were directly "connected" to in situ production by epilithic intertidal microalgae. The maximum body size of a widely distributed limpet, Patella granularis, was also positively correlated with level of in situ primary production. The maximal values of biomass attained by intertidal filter-feeders were not related to intertidal primary production, and were relatively constant around the coast. At a local scale, filter-feeder biomass is known to be strongly influenced by wave action. This implies that the local-scale water movements over-ride any effects that large-scale gradients of primary production may have on filter-feeders. The large-scale gradient in intertidal productivity around the coast is thus strongly linked with grazer biomass and individual body size, but any effect it has on filter-feeder biomass seems subsidiary to the local effects of wave action.

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