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1.
Int J Mol Sci ; 22(10)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34065020

RESUMEN

Although optical hyperthermia could be a promising anticancer therapy, the need for high concentrations of light-absorbing metal nanoparticles and high-intensity lasers, or large exposure times, could discourage its use due to the toxicity that they could imply. In this article, we explore a possible role of silica microparticles that have high biocompatibility and that scatter light, when used in combination with conventional nanoparticles, to reduce those high concentrations of particles and/or those intense laser beams, in order to improve the biocompatibility of the overall procedure. Our underlying hypothesis is that the scattering of light caused by the microparticles would increase the optical density of the irradiated volume due to the production of multiple reflections of the incident light: the nanoparticles present in the same volume would absorb more energy from the laser than without the presence of silica particles, resulting either in higher heat production or in the need for less laser power or absorbing particles for the same required temperature rise. Testing this new optical hyperthermia procedure, based on the use of a mixture of silica and metallic particles, we have measured cell mortality in vitro experiments with murine glioma (CT-2A) and mouse osteoblastic (MC3T3-E1) cell lines. We have used gold nanorods (GNRs) that absorb light with a wavelength of 808 nm, which are conventional in optical hyperthermia, and silica microparticles spheres (hereinafter referred to as SMSs) with a diameter size to scatter the light of this wavelength. The obtained results confirm our initial hypothesis, because a high mortality rate is achieved with reduced concentrations of GNR. We found a difference in mortality between CT2A cancer cells and cells considered non-cancer MC3T3, maintaining the same conditions, which gives indications that this technique possibly improves the efficiency in the cell survival. This might be related with differences in the proliferation rate. Since the experiments were carried out in the 2D dimensions of the Petri dishes, due to sedimentation of the silica particles at the bottom, whilst light scattering is a 3D phenomenon, a large amount of the energy provided by the laser escapes outside the medium. Therefore, better results might be expected when applying this methodology in tissues, which are 3D structures, where the multiple reflections of light we believe will produce higher optical density in comparison to the conventional case of no using scattering particles. Accordingly, further studies deserve to be carried out in this line of work in order to improve the optical hyperthermia technique.


Asunto(s)
Glioblastoma/terapia , Hipertermia Inducida , Nanopartículas del Metal/administración & dosificación , Osteoblastos/citología , Dióxido de Silicio/química , Animales , Supervivencia Celular , Células Cultivadas , Glioblastoma/patología , Rayos Láser , Nanopartículas del Metal/química , Ratones
2.
Environ Geochem Health ; 42(9): 2685-2701, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31912340

RESUMEN

Groundwater pollution in tropical and human-altered coastal landscapes is receiving novel attention due to decreasing in annual recharge as a consequence of recurrent droughts and overexploitation, whereby saline intrusion, point and diffuse source contamination, and water conflicts are common denominators. This study presents a detailed groundwater evaluation in a coastal aquifer within the central Pacific coast of Costa Rica. Three sampling campaigns including major ions, heavy metals, and fecal coliform analyses were conducted between July 2013 and March 2014 across 17 wells within the alluvial and fissured units of the Jacó aquifer. The groundwater system is classified as mixed HCO3--Ca2+-Mg2+ type. Coliforms presence was found in two wells, nearby Mona Creek headwaters and near the coastal line. Heavy metal concentrations were below quantification limits in most of the wells; however, chromium concentrations up to 6.56 µg/L were quantified within the coastal line and central portion of the alluvial aquifer in 20 out of the 48 samples. The spatial distribution of major ions (K+, Na+, Ca2+, Mg2+, Cl-, SO42-, and HCO3-) exhibited an increasing trend towards the central portion of the alluvial aquifer, which may be potentially associated with the large unregulated urban expansion, invoking a need of a continuous water quality monitoring program in this touristic hot spot. This study provides useful information for other similar coastal aquifers in Central America, whereby increasing population growth and unregulated touristic, industrial, and agricultural activities are posing a truly challenge to ensure water security and sustainability parallel to the economic development in a changing climate.


Asunto(s)
Agua Subterránea/análisis , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Agricultura , Costa Rica , Enterobacteriaceae , Monitoreo del Ambiente , Heces/microbiología , Agua Subterránea/microbiología , Humanos , Metales Pesados/análisis , Océano Pacífico , Microbiología del Agua , Calidad del Agua , Pozos de Agua
3.
Nanotechnology ; 30(35): 355101, 2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31082814

RESUMEN

Metallic nanorods are promising agents for a wide range of biomedical applications. We report an optical hyperthermia method capable of inducing slowdown tumor progression of an experimental in vivo CT-2A glioblastoma tumor. The tumor model used in this research is based on the transplantation of mouse astrocytoma CT-2A cells in the striatum of mice by intracranial stereotaxic surgery. Two weeks after cell implant, the resulting tumor is treated by irradiating intratumoral injected gold nanorods, biofunctionalized with CD133 antibody (B-GNRs), using a continuous wave laser. Nanoparticles convert the absorbed light into localized heat (reaching up to 44 °C) due to the effect of surface plasmon resonance. A significant slowdown in CT-2A tumor progression is evident, by histology and magnetic resonance imaging, at one (p = 0.03) and two weeks (p = 0.008) after irradiation treatment. A notable deceleration in tumor size (15%-75%) as compared to the control untreated groups, it is observed. Thus, laser irradiation of B-GNRs is found to be effective for the treatment of CT-2A tumor progression. Similarities between the pre-clinical CT-2A tumor model and the human astrocytoma disease, in terms of anatomy, metastatic behavior and histopathology, suggest that hyperthermic treatment by laser irradiation of B-GNRs administered into high-grade human astrocytoma might constitute a promising alternative treatment to limit the progression of this deadly disease.


Asunto(s)
Astrocitoma/terapia , Neoplasias Encefálicas/terapia , Oro/farmacología , Hipertermia Inducida/métodos , Terapia por Láser/métodos , Nanotubos/química , Antígeno AC133/antagonistas & inhibidores , Antígeno AC133/inmunología , Animales , Anticuerpos Neutralizantes/farmacología , Astrocitoma/inmunología , Astrocitoma/patología , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Oro/administración & dosificación , Oro/química , Humanos , Inyecciones Intralesiones , Rayos Láser , Ratones , Ratones Endogámicos C57BL , Nanotubos/ultraestructura , Trasplante de Neoplasias , Técnicas Estereotáxicas , Resonancia por Plasmón de Superficie , Carga Tumoral/efectos de la radiación
4.
Clin Genet ; 93(5): 1075-1080, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29231959

RESUMEN

Congenital lipomatous overgrowth with vascular, epidermal, and skeletal (CLOVES) anomalies and Klippel-Trenaunay (KTS) syndromes are caused by somatic gain-of-function mutations in PIK3CA, encoding a catalytic subunit of phosphoinositide 3-kinase. Affected tissue is needed to find mutations, as mutant alleles are not detectable in blood. Because some patients with CLOVES develop Wilms tumor, we tested urine as a source of DNA for mutation detection. We extracted DNA from the urine of 17 and 24 individuals with CLOVES and KTS, respectively, and screened 5 common PIK3CA mutation hotspots using droplet digital polymerase chain reaction. Six of 17 CLOVES participants (35%) had mutant PIK3CA alleles in urine. Among 8 individuals in whom a mutation had been previously identified in affected tissue, 4 had the same mutant allele in the urine. One study participant with CLOVES had been treated for Wilms tumor. We detected the same PIK3CA mutation in her affected tissue, urine, and tumor, indicating Wilms tumors probably arise from PIK3CA mutant cells in patients with CLOVES. No urine sample from a participant with KTS had detectable PIK3CA mutations. We suggest that urine, which has the advantage of being collected non-invasively, is useful when searching for mutations in individuals with CLOVES syndrome.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/genética , Síndrome de Klippel-Trenaunay-Weber/genética , Lipoma/genética , Anomalías Musculoesqueléticas/genética , Nevo/genética , Malformaciones Vasculares/genética , Tumor de Wilms/genética , Adolescente , Adulto , Alelos , Niño , Preescolar , ADN/genética , ADN/orina , Femenino , Predisposición Genética a la Enfermedad , Humanos , Lactante , Síndrome de Klippel-Trenaunay-Weber/patología , Síndrome de Klippel-Trenaunay-Weber/orina , Lipoma/patología , Lipoma/orina , Masculino , Persona de Mediana Edad , Anomalías Musculoesqueléticas/patología , Anomalías Musculoesqueléticas/orina , Mutación , Nevo/patología , Nevo/orina , Fenotipo , Malformaciones Vasculares/patología , Malformaciones Vasculares/orina , Tumor de Wilms/patología , Tumor de Wilms/orina
5.
Org Biomol Chem ; 15(46): 9855-9865, 2017 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-29139516

RESUMEN

Bioorthogonal dissociative reactions boast diverse potential applications in chemical biology and drug delivery. The reaction of benzonorbornadienes with tetrazines to release amines from carbamate leaving groups was recently introduced as a bioorthogonal bond-cleavage reaction. The present study aimed at investigating the scope of leaving groups that are compatible with benzonorbornadienes. Synthesis of several benzonorbornadienes with different releasable groups is reported, and the reaction of these molecules with tetrazine was found to be rapid and afforded high release yields. The tetrazine-induced release of molecules proceeds in a cascade of steps including inverse-electron demand cycloaddition and cycloreversion reactions that form unstable isoindoles/isobenzofuran intermediates and spontaneously eliminate a leaving group of interest. In the case of oxygen-bridged BNBDs at room temperature, we observed the formation of an unproductive byproduct.

6.
An Acad Bras Cienc ; 88(2): 933-40, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27192196

RESUMEN

This study aims to verify the effects of coconut oil supplementation (COS) in the body composition and lipid profile of rats submitted to physical exercise. The animals (n=6 per group) were randomly assigned to: G1=Sedentary and Non-supplemented (Control Group), G2=Sedentary and Supplemented, G3=Exercised and Non-supplemented and G4=Exercised and Supplemented. The COS protocol used was 3 mL/Kg of body mass by gavage for 28 days. The physical exercise was the vertical jumping training for 28 days. It was determined the body mass parameters, Lee Index, blood glucose and lipid profile. The COS did not interfere with body mass, but the lean body mass was lower in G3 compared to G2. The final Lee Index classified G1 and G2 as obese (>30g/cm). The lipid profile showed total cholesterol was decreased in G3, LDL-c concentration was decreased in G2, triglycerides, VLDL-c and HDL-c concentrations were increased in G2 and G4 in relation to G1 and G3. The COS decreased LDL-c/HDL-c ratio. In conclusion, the COS associated or not to physical exercise worsen others lipid parameters, like triglycerides and VLDL-c level, showing the care with the use of lipid supplements.


Asunto(s)
Composición Corporal/efectos de los fármacos , Aceite de Coco/farmacología , Animales , Aceite de Coco/administración & dosificación , Lípidos/análisis , Obesidad/diagnóstico , Condicionamiento Físico Animal , Distribución Aleatoria , Ratas , Triglicéridos/análisis
7.
Ginecol Obstet Mex ; 84(2): 122-5, 2016 Feb.
Artículo en Español | MEDLINE | ID: mdl-27290838

RESUMEN

CASE REPORT: We report the case of a 55-year-old patient who pre- sented a pelvic mass, ascites and elevated serum CA125. Suspecting a malignant process she underwent surgery and a total hysterectomy with bilateral salpigo-oforectomy was performed. Pathologic report revealed a bilateral ovarian fibroma and non-tumoral ascites. The presence of elevated serum CA125 levels in a postmenopausal woman with a pelvic mass and ascites suggest an ovarian malignant disease. However, in case of Meigs'syndrome, all symptoms will diappear after removal of the pelvic tumor, so a fast surgical management of the patients is mandatory.


Asunto(s)
Fibroma/diagnóstico , Síndrome de Meigs/diagnóstico , Neoplasias Ováricas/diagnóstico , Ascitis/etiología , Antígeno Ca-125/sangre , Femenino , Fibroma/patología , Fibroma/cirugía , Humanos , Histerectomía/métodos , Síndrome de Meigs/etiología , Persona de Mediana Edad , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Posmenopausia
8.
Cancer Causes Control ; 24(2): 241-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23184121

RESUMEN

PURPOSE: Currently, studies on serologic diagnosis of Helicobacter pylori-associated gastric cancer (GC) in Latin America are scarce. The aim of the present study was to evaluate the association between H. pylori serology tests in patients with early precancerous lesions or GC, when compared with non-atrophic gastritis in Colombia, Paraguay, and Mexico, three countries in Latin America with a high prevalence of H. pylori infection but contrasting rates of GC mortality. METHODS: Gastric biopsies and blood samples were obtained from patients attending the gastroenterology or oncology services of hospitals in the three participating countries. IgG antibodies against H. pylori whole-cell antigens and CagA were tested in 1,117 sera using an enzyme-linked immunoabsorbent assay. RESULTS: Positive and significant associations were shown for H. pylori seropositivity and preneoplastic lesions in Mexico (OR 2.0; 95 % CI 1.1-3.4) but not in Colombia (OR 1.2; 95 % CI 0.6-2.1) or Paraguay (OR 1.5; 95 % CI 0.6-3.2); no significant associations were shown for GC in any country. CagA seropositivity was associated with preneoplasic lesions in all three countries (ORs = 2.1, 3.0, and 3.1 for Mexico, Colombia, and Paraguay, respectively), and with GC only in Colombia (OR 4.3; 95 % CI 2.1-9.2). CONCLUSIONS: In countries of Latin America, the IgG CagA test might be a useful biomarker for patients with gastric preneoplastic lesions and for those at risk of developing gastric cancer.


Asunto(s)
Biomarcadores de Tumor/sangre , Infecciones por Helicobacter/sangre , Helicobacter pylori/aislamiento & purificación , Lesiones Precancerosas/sangre , Lesiones Precancerosas/microbiología , Neoplasias Gástricas/sangre , Neoplasias Gástricas/microbiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/epidemiología , Lesiones Precancerosas/patología , Neoplasias Gástricas/epidemiología
9.
Neuropathol Appl Neurobiol ; 39(7): 722-35, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23941684

RESUMEN

Brain ischaemia and reperfusion produce alterations in the microenvironment of the parenchyma, including ATP depletion, ionic homeostasis alterations, inflammation, release of multiple cytokines and abnormal release of neurotransmitters. As a consequence, the induction of proliferation and migration of neural stem cells is redirected towards the peri-infarct region. The success of new neurorestorative treatments for damaged brain implies the need to describe with greater accuracy the mechanisms in charge of regulating adult neurogenesis, under both physiological and pathological conditions. Recent evidence demonstrates that many neurotransmitters, glutamate in particular, control the subventricular zone (SVZ), thus being part of the complex signal network that exerts a remarkable influence on the production of new neurones. Neurotransmitters provide a link between brain activity and SVZ neurogenesis. Therefore, a deeper knowledge of the role of neurotransmitters systems, such as glutamate and its transporters, in adult neurogenesis, may prove a valuable tool to be utilized as a neurorestorative therapy in this pathology.


Asunto(s)
Isquemia Encefálica/metabolismo , Neurogénesis/fisiología , Neuronas/citología , Neurotransmisores/metabolismo , Accidente Cerebrovascular/patología , Animales , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Isquemia Encefálica/patología , Humanos
10.
Eur Rev Med Pharmacol Sci ; 27(16): 7738-7748, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37667952

RESUMEN

OBJECTIVE: The aim of this study was to develop an initial valid tool to measure attitudes toward cancer-related cognitive changes. SUBJECTS AND METHODS: After revising the literature, three main dimensions were hypothesized. Eight judges were contacted to obtain content validity evidence. A robust Exploratory Factor Analysis (EFA) was performed via a parallel analysis with an Unweighted Least Squares (ULS) estimator and polychoric correlations. The results were crossed with sociodemographic variables to find possible statistical differences and estimate the size effect. Analysis was performed in the software Factor and the statistical package R. RESULTS: A sample of 374 participants was obtained, involving oncology patients, their caregivers, and people from the general community. A statistical fit was found in two dimensions: Awareness and Judgments [root mean squared error of approximation (RMSEA) = 0.042, standardized root mean square residual (SRMR) = 0.02, comparative fit index (CFI) = 0.99, Tucker-Lewis index (TLI) = 0.98] with a moderate correlation between them (r = 0.612). Optimal reliability indices were obtained for the total scale and its dimensions. No real statistical difference was found between sociodemographic variables; the interpretation norms were established via the quartiles. CONCLUSIONS: The first attempt to measure the construct of interest was developed with two primary validity evidence based on the content and its internal structure. This instrument could help strengthen the prevention of cancer-related cognitive changes. More research is needed to adhere more valid evidence to the scale.


Asunto(s)
Oncología Médica , Neoplasias , Humanos , Colombia , Reproducibilidad de los Resultados , Programas Informáticos , Cognición
11.
Sci Total Environ ; 844: 156941, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-35753477

RESUMEN

The inter-mountainous region of central Honduras has been experiencing abrupt urban drinking water shortages during the last decade. Land use fragmentation and rainfall deficits have rapidly reduced surface water quality and quantity in this region. Here we present a 3-yr (2018-2020) tracer study within the headwaters of the Choluteca River basin (2949 km2). We sampled rainfall (weekly N = 156; daily N = 270), drilled wells (N = 166; up to ~300 m depth), boreholes (N = 70; ~4-12 m depth), and springs (N = 128) to assess the spatiotemporal connectivity between rainfall and mean groundwater recharge elevations (MREs). Clear W-shaped incursions characterized rainfall isotopic seasonality from the dry to the wet season. Air mass back trajectory analysis revealed three primary moisture sources: 73 % (east, Caribbean Sea), 17 % (southwest, Pacific Ocean), and 10 % (north; Gulf of Mexico). Groundwater sources exhibited a strong meteoric origin with evidence of secondary evaporation evolution, characterized by low d-excess values. MREs for the drilled wells ranged from 821 to 2018 m asl with a mean value of 1570 ± 150 m asl. Seasonal isotopic variability during dry-wet transitions and the influence of rapid infiltration limited the performance of the MRE method in springs and boreholes. MREs coincided primarily with coniferous forests, pasture, and crop areas, within regions of moderate to high transmissivity. These results are intended to guide the mapping and delineation of critical recharge areas in central Honduras to enhance municipal water regulations, effective environmental protection, and long-term conservation practices.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Monitoreo del Ambiente/métodos , Honduras , Isótopos/análisis , Isótopos de Oxígeno/análisis , Ríos
12.
Nat Commun ; 13(1): 7529, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36477027

RESUMEN

Precision oncology research is challenging outside the contexts of oncogenic addiction and/or targeted therapies. We previously showed that phosphoproteomics is a powerful approach to reveal patient subsets of interest characterized by the activity of a few kinases where the underlying genomics is complex. Here, we conduct a phosphoproteomic screening of samples from HER2-negative female breast cancer receiving neoadjuvant paclitaxel (N = 130), aiming to find candidate biomarkers of paclitaxel sensitivity. Filtering 11 candidate biomarkers through 2 independent patient sets (N = 218) allowed the identification of a subgroup of patients characterized by high levels of CDK4 and filamin-A who had a 90% chance of achieving a pCR in response to paclitaxel. Mechanistically, CDK4 regulates filamin-A transcription, which in turn forms a complex with tubulin and CLIP-170, which elicits increased binding of paclitaxel to microtubules, microtubule acetylation and stabilization, and mitotic catastrophe. Thus, phosphoproteomics allows the identification of explainable factors for predicting response to paclitaxel.


Asunto(s)
Neoplasias de la Mama , Paclitaxel , Femenino , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Quinasa 4 Dependiente de la Ciclina , Genómica , Paclitaxel/farmacología , Medicina de Precisión
13.
Bioorg Med Chem ; 19(16): 4876-81, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21775156

RESUMEN

Phytochemical investigations of the n-hexane extract from the roots of Peltodon longipes (Lamiaceae) resulted in the isolation of 12 known abietane diterpenes (1-12). Structures were established on the basis of one and two dimensional nuclear magnetic resonance spectroscopic data ((1)H and (13)C, COSY, HSQC and HMBC), electron ionization mass spectrometric analysis (EIMS) as well as comparison with data from literature. These compounds, as well as eight known diterpenes (13-19) from Salvia miltiorrhiza, and two from Salvia sahendica (20 and 21) were evaluated for their cytotoxic effects in human pancreatic (MIAPaCa-2) and melanoma (MV-3) tumor cell lines using the MTT assay. Tanshinone IIa (13), 7α-acetoxyroyleanone (1), 1,2-dihydrotanshinone (16) and cryptotanshinone (14) had the highest cytotoxic effects in MIAPaCa-2, displaying IC(50) of 1.9, 4.7, 5.6, and 5.8 µM, respectively. Structure-activity relationships of abietane diterpenoid quinones are discussed.


Asunto(s)
Abietanos/farmacología , Antineoplásicos Fitogénicos/farmacología , Citotoxinas/farmacología , Lamiaceae , Extractos Vegetales/farmacología , Salvia , Abietanos/análisis , Abietanos/química , Abietanos/aislamiento & purificación , Antineoplásicos Fitogénicos/análisis , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Citotoxinas/química , Citotoxinas/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Fitoterapia , Extractos Vegetales/análisis , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas , Relación Estructura-Actividad
14.
Neurologia ; 26(2): 105-10, 2011 Mar.
Artículo en Inglés, Español | MEDLINE | ID: mdl-21163186

RESUMEN

INTRODUCTION: The progress of effective therapies for stroke has become a challenging task for both researchers and clinicians. Some pitfalls in clinical trials might have their origins in the pre-clinical experimental ischaemic models for the evaluation of potential neuro-protective agents. METHODS: We aim to standardise the methods for the development of stroke animal models throughout Spain, to produce document with appropriate recommendations and best practice in order to improve experimental methods in the field of stroke research. RESULTS: Members of several experienced stroke research groups prepared a guide with recommendations in the application of focal cerebral ischaemic models. The main features of this guide are based on the selection of the most appropriate animal model, taking in account the objective of the study, the species, strain, age, sex of animals, as well as risk factors. The experimental design must include a sham control group and the sample size calculation. Animal randomisation and blind analysis, masked assessment of outcomes, monitoring of body temperature and cerebral blood flow, and the reporting of reasons for excluding animals from the study, as well as the mortality rate, are other main points to fulfil in the application of stroke models. CONCLUSIONS: Standardised methods are essential to increase the success of the pre-clinical findings in the stroke neuroprotection field to be able to translate to the clinical practice.


Asunto(s)
Investigación Biomédica/normas , Modelos Animales de Enfermedad , Accidente Cerebrovascular , Animales , Guías como Asunto
15.
J Med Screen ; 28(2): 70-79, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32517538

RESUMEN

OBJECTIVE: To assess the determinants of the participation rate in breast cancer screening programs by conducting a systematic review of reviews. METHODS: We conducted a systematic search in PubMed via Medline, Scopus, Embase, and Cochrane identifying the literature up to April 2019. Out of 2258 revealed unique abstracts, we included 31 reviews, from which 25 were considered as systematic. We applied the Walsh & McPhee Systems Model of Clinical Preventive Care to systematize the determinants of screening participation. RESULTS: The reviews, mainly in high-income settings, reported a wide range for breast cancer screening participation rate: 16-90%. The determinants of breast cancer screening participation were simple low-cost interventions such as invitation letters, basic information on screening, multiple reminders, fixed appointments, prompts from healthcare professionals, and healthcare organizational factors (e.g. close proximity to screening facility). More complex interventions (such as face-to-face counselling or home visits), mass media or improved access to transport should not be encouraged by policy makers unless other information appears. The repeated participation in mammography screening was consistently high, above 62%. Previous positive experience with screening influenced the repeated participation in screening programs. The reviews were inconsistent in the use of terminology related to breast cancer screening participation, which may have contributed to the heterogeneity in the reported outcomes. CONCLUSIONS: This study shows that consistent findings of systematic reviews bring more certainty into the conclusions on the effects of simple invitation techniques, fixed appointments and prompts, as well as healthcare organizational factors on promoting participation rate in screening mammography.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/diagnóstico , Detección Precoz del Cáncer , Femenino , Humanos , Mamografía , Tamizaje Masivo , Revisiones Sistemáticas como Asunto
16.
Sci Total Environ ; 754: 142258, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33254946

RESUMEN

Groundwater plays an important role in the economic development of the Chaco-Pampean Plain (Argentina), where industry, agriculture and cattle farming are the main economic activities. The 66% of the country's population lives in this area. The low slopes of this region condition the water movement and the occurrence of physical and chemical processes. The aim of this work is to update the hydrological conceptual model of the Del Azul Creek basin (Buenos Aires Province), a sub-humid and continental plain, using environmental tracers. In total, the study was based on the analysis of 201 samples (stable isotopes) and 184 samples (chemical data) including rainwater, surface water and groundwater. The temporal and spatial variation in the isotopic composition of rainfall and the hydrological physical-processes, evaporation, surface water-groundwater interaction and recharge were studied. Isotopic compositions of rainfall revealed a seasonal variation across the basin. Low δ18O rainfalls occur during the coldest seasons, while high δ18O rainfalls occur during the warmest seasons. The isotopic compositions of rainfall varied only during the cold period in the upper basin. At this time, the lowest δ18O rainfall fell in the upper basin, while in the other areas and during the warmer seasons, no differences were observed. Evaporation was a relevant process in the flatter area of the basin, mainly during the warmest seasons. Samples taken from the wetlands and from the lower section of the Del Azul Creek were strongly evaporated. In the first 30 m depth of the aquifer, groundwater reflected the isotopic composition of rainfall from the warmest seasons, thus revealing seasonal preferential recharge and a good hydraulic connection. This study provides direct evidence showing that both evaporation and the surface water-groundwater interaction are processes that play a key role in the control of the isotopic and chemical composition of water.

17.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33191151

RESUMEN

PURPOSE: To describe the results of MRI (magnetic resonance image) guided ROLL (radioguided occult lesion localization) and SNOLL (sentinel node occult lesion localization) in the localization of residual disease after neoadjuvant chemotherapy for breast cancer, as well as assessing the surgical results obtained and disease free survival. METHODS: Prospective observational analysis of 132 patients with 136 tumors, treated with neoadjuvant chemotherapy at our hospital between 2011-2017. Residual disease was located presurgically with MRI guided ROLL/SNOLL technique. We analyzed technical aspects of localization, and variables corresponding to surgical procedures and events occurred during follow-up. RESULTS: The median tumor size was of 20.5mm (interquartilic range [IQR]: 14-28). The majority (96.3%) were invasive ductal carcinomas. Sentinel lymph node detection rate was 98.9%. Complete pathological response (CPR) in the breast was achieved in 58.1% of cases. The rate of affected margins in 89 cases operated by conservative surgery was 2.2%. With a median follow-up of 50 months (IQR: 37-61) we found a 7.4% rate of relapses. Of these, seven were loco-regional and three at distant sites. The estimated mean of disease-free survival time was 83.2 months (Confidence Interval [CI] 95%: 79.6-86.6). CONCLUSIONS: MRI guided ROLL/SNOLL is a great tool for breast cancer residual disease localization following neoadjuvant chemotherapy. In addition, this technique attains good loco-regional control of the diseases and has excellent surgical results.

18.
Environ Sci Technol ; 44(17): 6901-4, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20704282

RESUMEN

This paper presents a new solids looping process for capturing CO2 while generating hydrogen and/or electricity from natural gas. The process is based on the sorption enhanced reforming of CH4, employing CaO as a high temperature CO2 sorbent, combined with a second chemical loop of CuO/Cu. The exothermic reduction of CuO with CH4 is used to obtain the heat necessary for the decomposition of the CaCO3 formed in the reforming step. The main part of the process is completed by the oxidation of Cu to CuO, which is carried out with air diluted with a product gas recycle of this reactor at sufficiently low temperatures and high pressures to avoid the decomposition of a substantial fraction of CaCO3.


Asunto(s)
Calcio/química , Dióxido de Carbono/química , Cobre/química , Hidrógeno/química , Fuentes Generadoras de Energía , Presión , Temperatura
19.
Br J Cancer ; 100(7): 1184-90, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19293802

RESUMEN

Little is known about the dynamics of human papillomavirus (HPV) infection and subsequent development of high-grade cervical intraepithelial neoplasia (CIN2/3), particularly in women >30 years of age. This information is needed to assess the impact of HPV vaccines and consider new screening strategies. A cohort of 1728 women 15-85 years old with normal cytology at baseline was followed every 6 months for an average of 9 years. Women with squamous intraepithelial lesions were referred for biopsy and treatment. The Kaplan-Meier method was used to estimate the median duration of infection and Cox regression analysis was undertaken to assess determinants of clearance and risk of CIN2/3 associated with HPV persistence. No difference in the likelihood of clearance was observed by HPV type or woman's age, with the exception of lower clearance for HPV16 infection in women under 30 years of age. Viral load was inversely associated with clearance. In conclusion, viral load is the main determinant of persistence, and persistence of HPV16 infections carry a higher risk of CIN2/3.


Asunto(s)
Infecciones por Papillomavirus/complicaciones , Displasia del Cuello del Útero/etiología , Neoplasias del Cuello Uterino/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Persona de Mediana Edad , Riesgo , Carga Viral
20.
Neuroscience ; 158(4): 1390-6, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19135137

RESUMEN

Stroke is the second most common cause of death and major cause of disability worldwide. Actual treatment involves surgery and/or thrombolytic drugs, but there is an urgent need for new approaches. Periodic acceleration, a rocking headward to footward movement of the whole body, is a non-invasive method to induce pulsatile shear stress on the vascular endothelium eliciting an enhanced production and secretion of endothelium-derived products such as nitric oxide, prostacyclin, prostaglandin E2, tissue plasminogen activator (tPA), and adrenomedullin. All these products have been shown to protect the brain from ischemic injuries. A rat model of focal brain ischemia was treated with application of periodic acceleration for 3 h immediately after the onset of ischemia. Controls remained static for the same period of time. Brain damage was assessed by magnetic resonance imaging (MRI) and biochemical markers. A significant reduction in brain damage was observed, 7 days post-ischemia, in rocked rats when compared with the static controls, through MRI. Furthermore, rocked animals had significantly lower levels of Beclin 1 and fractin than their static counterparts, and some isoforms of nitric oxide synthase were regulated by periodic acceleration. Our results show that periodic acceleration may provide a novel, affordable, non-invasive therapeutic option for the treatment of stroke.


Asunto(s)
Aceleración , Lesiones Encefálicas/etiología , Lesiones Encefálicas/terapia , Isquemia Encefálica/complicaciones , Terapia por Ejercicio/métodos , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Beclina-1 , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Isquemia Encefálica/inducido químicamente , Isquemia Encefálica/etiología , Caspasa 3/genética , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Endotelina-1 , Regulación de la Expresión Génica/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa/metabolismo , Periodicidad , Ratas , Ratas Wistar , Factores de Tiempo
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