Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 144(5): 703-18, 2011 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-21376233

RESUMEN

Among breast cancers, triple-negative breast cancer (TNBC) is the most poorly understood and is refractory to current targeted therapies. Using a genetic screen, we identify the PTPN12 tyrosine phosphatase as a tumor suppressor in TNBC. PTPN12 potently suppresses mammary epithelial cell proliferation and transformation. PTPN12 is frequently compromised in human TNBCs, and we identify an upstream tumor-suppressor network that posttranscriptionally controls PTPN12. PTPN12 suppresses transformation by interacting with and inhibiting multiple oncogenic tyrosine kinases, including HER2 and EGFR. The tumorigenic and metastatic potential of PTPN12-deficient TNBC cells is severely impaired upon restoration of PTPN12 function or combined inhibition of PTPN12-regulated tyrosine kinases, suggesting that TNBCs are dependent on the proto-oncogenic tyrosine kinases constrained by PTPN12. Collectively, these data identify PTPN12 as a commonly inactivated tumor suppressor and provide a rationale for combinatorially targeting proto-oncogenic tyrosine kinases in TNBC and other cancers based on their profile of tyrosine-phosphatase activity.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 12/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 12/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Transformación Celular Neoplásica , Receptores ErbB/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Sistema de Señalización de MAP Quinasas , MicroARNs/metabolismo , Mutación , Metástasis de la Neoplasia , Procesamiento Proteico-Postraduccional
2.
Clin Infect Dis ; 78(2): 248-258, 2024 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-37738153

RESUMEN

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAb) is 1 of the most problematic antimicrobial-resistant bacteria. We sought to elucidate the international epidemiology and clinical impact of CRAb. METHODS: In a prospective observational cohort study, 842 hospitalized patients with a clinical CRAb culture were enrolled at 46 hospitals in five global regions between 2017 and 2019. The primary outcome was all-cause mortality at 30 days from the index culture. The strains underwent whole-genome analysis. RESULTS: Of 842 cases, 536 (64%) represented infection. By 30 days, 128 (24%) of the infected patients died, ranging from 1 (6%) of 18 in Australia-Singapore to 54 (25%) of 216 in the United States and 24 (49%) of 49 in South-Central America, whereas 42 (14%) of non-infected patients died. Bacteremia was associated with a higher risk of death compared with other types of infection (40 [42%] of 96 vs 88 [20%] of 440). In a multivariable logistic regression analysis, bloodstream infection and higher age-adjusted Charlson comorbidity index were independently associated with 30-day mortality. Clonal group 2 (CG2) strains predominated except in South-Central America, ranging from 216 (59%) of 369 in the United States to 282 (97%) of 291 in China. Acquired carbapenemase genes were carried by 769 (91%) of the 842 isolates. CG2 strains were significantly associated with higher levels of meropenem resistance, yet non-CG2 cases were over-represented among the deaths compared with CG2 cases. CONCLUSIONS: CRAb infection types and clinical outcomes differed significantly across regions. Although CG2 strains remained predominant, non-CG2 strains were associated with higher mortality. Clinical Trials Registration. NCT03646227.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Humanos , Acinetobacter baumannii/genética , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Estudios Prospectivos , Pruebas de Sensibilidad Microbiana , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
3.
Camb Q Healthc Ethics ; 29(4): 585-591, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32892778

RESUMEN

This paper analyzes in the use of virtual reality when used to induce full-body ownership in violent offenders in order to elicit empathetic feelings by allowing them to embody the virtual body of a victim of domestic abuse. The authors explore potentially harmful effects to individuals participating in this kind of therapy and question whether consent is fully informed. The paper concludes with guidelines for ethical research and rehabilitation using this innovative technology.


Asunto(s)
Ilusiones , Terapia de Exposición Mediante Realidad Virtual , Realidad Virtual , Humanos , Consentimiento Informado , Propiedad
4.
Methods Mol Biol ; 2793: 55-64, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38526723

RESUMEN

Phage-assisted evolution has emerged as a powerful technique for improving a protein's function by using mutagenesis and selective pressure. However, mutations typically occur throughout the host's genome and are not limited to the gene-of-interest (GOI): these undesirable genomic mutations can yield host cells that circumvent the system's selective pressure. Our system targets mutations specifically toward the GOI by combining T7 targeted mutagenesis and phage-assisted evolution. This system improves the structure and function of proteins by accumulating favorable mutations that can change its binding affinity, specificity, and activity.


Asunto(s)
Bacteriófagos , Bacteriófagos/genética , Mutación , Mutagénesis , Bacteriófago T7/genética
5.
PLoS One ; 18(11): e0295303, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38033135

RESUMEN

BACKGROUND & PURPOSE: Previous research has noted that Hispanic pre-adolescents may be at an increased probability for engagement in risk-taking behaviors. The purpose of this study was to explore parent-child communication among Hispanic parents and 4th-6th grade children related to substance use, puberty, sex, and social media use. METHODS: A qualitative descriptive design was used to examine Hispanic parents'/caregivers' communication with their children about substance use behaviors, pubertal developments, engagement in sexual risk behaviors, and social media use. The study included two components: four focus groups consisting of 23 children; five focus groups and one interview consisting of 24 adults. All were conducted until data saturation was reached. Parents and pre-adolescents were interviewed separately. Interviews with parents and pre-adolescents were audio-recorded, transcribed verbatim, and analyzed using content analysis techniques. RESULTS & CONCLUSION: The themes that emerged from the interviews were about children's feelings, parents' feelings, communication messages that children received from their parents, and information parents provided to their children during parent-child communication. The results indicate discrepancies between information that parents provided and information that the pre-adolescents reported. The results have implications for healthcare providers in that parents need to be better educated on communicating effectively with their pre-adolescents about risk-taking behaviors. Healthcare providers may help facilitate parent-child communication with Hispanic families. More research is needed to develop intervention programs for Hispanic parents to learn how to effectively communicate with their pre-adolescent children in a developmentally appropriate manner.


Asunto(s)
Relaciones Padres-Hijo , Medios de Comunicación Sociales , Trastornos Relacionados con Sustancias , Adulto , Humanos , Comunicación , Hispánicos o Latinos , Padres , Pubertad , Niño
6.
Camb Q Healthc Ethics ; 26(2): 288-291, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28361726
7.
Breast Cancer Res ; 13(6): R121, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22123186

RESUMEN

INTRODUCTION: The human epidermal growth factor receptor 2 (HER2)-targeted therapies trastuzumab (T) and lapatinib (L) show high efficacy in patients with HER2-positive breast cancer, but resistance is prevalent. Here we investigate resistance mechanisms to each drug alone, or to their combination using a large panel of HER2-positive cell lines made resistant to these drugs. METHODS: Response to L + T treatment was characterized in a panel of 13 HER2-positive cell lines to identify lines that were de novo resistant. Acquired resistant lines were then established by long-term exposure to increasing drug concentrations. Levels and activity of HER2 and estrogen receptor (ER) pathways were determined by qRT-PCR, immunohistochemistry, and immunoblotting assays. Cell growth, proliferation, and apoptosis in parental cells and resistant derivatives were assessed in response to inhibition of HER or ER pathways, either pharmacologically (L, T, L + T, or fulvestrant) or by using siRNAs. Efficacy of combined endocrine and anti-HER2 therapies was studied in vivo using UACC-812 xenografts. RESULTS: ER or its downstream products increased in four out of the five ER+/HER2+ lines, and was evident in one of the two intrinsically resistant lines. In UACC-812 and BT474 parental and resistant derivatives, HER2 inhibition by T reactivated HER network activity to promote resistance. T-resistant lines remained sensitive to HER2 inhibition by either L or HER2 siRNA. With more complete HER2 blockade, resistance to L-containing regimens required the activation of a redundant survival pathway, ER, which was up-regulated and promoted survival via various Bcl2 family members. These L- and L + T-resistant lines were responsive to fulvestrant and to ER siRNA. However, after prolonged treatment with L, but not L + T, BT474 cells switched from depending on ER as a survival pathway, to relying again on the HER network (increased HER2, HER3, and receptor ligands) to overcome L's effects. The combination of endocrine and L + T HER2-targeted therapies achieved complete tumor regression and prevented development of resistance in UACC-812 xenografts. CONCLUSIONS: Combined L + T treatment provides a more complete and stable inhibition of the HER network. With sustained HER2 inhibition, ER functions as a key escape/survival pathway in ER-positive/HER2-positive cells. Complete blockade of the HER network, together with ER inhibition, may provide optimal therapy in selected patients.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Antineoplásicos/farmacología , Neoplasias de la Mama/metabolismo , Quinazolinas/farmacología , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos/genética , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Lapatinib , Ratones , Ratones Desnudos , Quinazolinas/uso terapéutico , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/genética , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Receptores de Estrógenos/antagonistas & inhibidores , Receptores de Estrógenos/genética , Trastuzumab , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Rev Panam Salud Publica ; 30(6): 627-33, 2011 Dec.
Artículo en Español | MEDLINE | ID: mdl-22358414

RESUMEN

OBJECTIVE: Describe and compare the frequency of bacterial resistance phenotypes of microorganisms obtained from patients in intensive care units (ICU) and other (non-ICU) high-complexity public and private hospital services in Colombia. METHODS: A retrospective observational, analytical, multicenter study was conducted. The records from January 2007 to December 2009 on bacterial isolates and bacterial resistance phenotypes of microorganisms obtained from ICU and non-ICU patients in 79 high-complexity public and private hospitals were consolidated. The information was analyzed with the WHONET(®) 5.5 (WHO) software, following the 2009 recommendations of the Clinical and Laboratory Standards Institute, and summarized on an Excel(®) spreadsheet. A descriptive analysis with the calculation of proportions was performed. The trends were analyzed with Spearman rank correlation. RESULTS: The 2007-2009 trends for bacterial resistance phenotypes show increased percentages of vancomycin-resistant Enterococcus faecium, imipenem-resistant Klebsiella pneumoniae, ciprofloxacin-resistant K. pneumoniae, ceftazidime-resistant Escherichia coli and cefotaxime-resistant Enterobacter cloacae (r = 1, P < 0.01), and reduced percentages of ciprofloxacin-resistant E. coli, ceftazidime-resistant K. pneumoniae, oxacillin-resistant Staphylococcus aureus, ceftazidime-resistant Pseudomonas aeruginosa, and ciprofloxacin-resistant P. aeruginosa (r = -1, P < 0.01). CONCLUSIONS: The trend analysis presented in this study is the baseline for establishing a national epidemiological surveillance subsystem. The trends observed reveal that bacterial resistance to antimicrobial drugs in hospitals in Colombia is a dynamic phenomenon, with evidence of the emergence of vancomycin-resistant E. faecium and imipenem-resistant K. pneumoniae phenotypes in the hospitals.


Asunto(s)
Farmacorresistencia Microbiana , Hospitales Privados/estadística & datos numéricos , Hospitales Públicos/estadística & datos numéricos , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/microbiología , Colombia/epidemiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Humanos , Morbilidad/tendencias , Fenotipo , Vigilancia de la Población , Estudios Retrospectivos , Resistencia a la Vancomicina
9.
Nano Lett ; 10(12): 4920-8, 2010 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-21090693

RESUMEN

Nanoparticle-based therapeutics with local delivery and external electromagnetic field modulation holds extraordinary promise for soft-tissue cancers such as breast cancer; however, knowledge of the distribution and fate of nanoparticles in vivo is crucial for clinical translation. Here we demonstrate that multiple diagnostic capabilities can be introduced in photothermal therapeutic nanocomplexes by simultaneously enhancing both near-infrared fluorescence and magnetic resonance imaging (MRI). We track nanocomplexes in vivo, examining the influence of HER2 antibody targeting on nanocomplex distribution over 72 h. This approach provides valuable, detailed information regarding the distribution and fate of complex nanoparticles designed for specific diagnostic and therapeutic functions.


Asunto(s)
Neoplasias de la Mama/terapia , Nanopartículas , Animales , Línea Celular Tumoral , Campos Electromagnéticos , Femenino , Fluorescencia , Humanos , Imagen por Resonancia Magnética , Ratones , Espectroscopía Infrarroja Corta
10.
Environ Pollut ; 265(Pt A): 115034, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32806412

RESUMEN

The influence of palm oil biodiesel content on the cytotoxicity, mutagenicity and genotoxicity of particle- and gas-phase diesel vehicle emissions was investigated. The emissions were collected on-board of a EURO IV diesel truck, fuelled with mixtures of 10% (B10), 20% (B20) and 100% (B100) of palm oil biodiesel, under real driving conditions. Organic extracts of the particulate matter (PM) and gases were characterised for 17 PAH (including EPA priority) and used for the biological assay. Increasing biodiesel content in the fuel mixture results in a decrease in the PM and PAH emission factors, both in the particulate and gas-phase. The majority of the PAH are present in the gas-phase. The mutagenic potencies, in TA98 bacteria, are higher for B20 in both phases, whereas the mutagenicity emission factor, that takes into account the lower emission of PM and PAH, is not significantly different between the fuels. Higher direct mutagenicity (TA98 + S9) is observed in all the tested fuels, indicating the action of carcinogenic compounds other than non-substituted PAH. The gas-phase extracts present higher cytotoxicity and genotoxicity in lung epithelial cell A549, which may be related to the higher PAH content in the gas-phase. The increase in biodiesel content have a different impact on cytotoxicity, being larger in the gas-phase and lower in the particle-phase. This indicates that pulmonary toxicity may be higher for the gaseous emissions, due to the role of different toxic compounds compared to the PM. The adverse biological effects when biodiesel content increases are not consequent with the reduction of the PAH characterised, indicating that other toxic compounds are more relevant. Further investigations to identify these compounds are required in order to update and focus the efforts regarding emission targets and controls.


Asunto(s)
Contaminantes Atmosféricos/análisis , Biocombustibles/análisis , Daño del ADN , Gases , Mutágenos , Aceite de Palma
11.
Int J Infect Control ; 16(3): 1-6, 2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34135996

RESUMEN

Infection control and antimicrobial stewardship programs (ICASPs) are essential to reduce the emergence and spread of antimicrobial resistance. The primary objective of this study was to assess the feasibility of extending a commercial off-the-shelf (COTS) software for ICASPs in low- and middle-income countries (LMICs). This project involved three hospitals in Colombia, including Centro Médico Imbanaco, Clínica San Francisco, and DIME Clínica Neurocardiovascular. A COTS platform (ILÚM Health Solutions™ Kenilworth, NJ) was extended to function in a range of technology settings, and translatable to almost any language. ICASP features were added, including clinical practice guidelines, hand hygiene (HH) documentation, and isolation precaution (IP) documentation. The platform was delivered as a smartphone mobile application ("app") for both iOS and Android. The app was successfully implemented at all sites, however, full back-end data integration was not feasible at any site. In contrast to the United States, a suite of surveillance tools and physician-focused decision support without patient data proved to be valuable. Language translation processing occurred quickly and incurred minimal costs. HH and IP compliance tracking were the most used features among ICASP staff; treatment guidelines were most often used by physicians. Use of the app streamlined activities and reduced the time spent on ICASP tasks. Users consistently reported positive impressions including simplicity of design, ease of navigation, and improved efficiency. This ICASP app was feasible in limited-resource settings, highly acceptable to users, and represents an innovative approach to antimicrobial resistance prevention.

12.
Clin Ophthalmol ; 14: 3427-3438, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33116395

RESUMEN

PURPOSE: To describe ocular surface characteristics and tests' results in a healthy pediatric population. METHODS: We performed a cross-sectional study with 60 healthy children, obtaining consent, OSDI and screen use survey and conducting ocular surface tests. Statistical univariate analysis for categorical and quantitative variables was made. To describe the correlation of the results in both eyes, we used a model of random effects. To characterize the possible profiles of device use, we applied the mixed-cluster methodology. RESULTS: Sixty healthy children between 7 and 17 years old were evaluated. Girl's proportion was 41.6%. Mean Ocular Surface Disease Index Score was 9.98±8.49 points. Daily screen time was 5.59±2.77 hours and the most popular screen was the smartphone. Mean results (with standard deviations or confidence intervals) of ocular surface tests were blink frequency while reading on paper, 6.8±5.68 times per minute; blink frequency while reading on screen, 8.7±7.14 times per minute; tear meniscus height, 0.19[0.18-0.2] mm; non-invasive tear break-up time, 12.44[10.99-13.9] seconds; nasal conjunctival redness, 0.86[0.77-0.94]; temporal conjunctival redness, 0.96[0.87-1.04]; tear osmolarity, 299.3[295.14-303.45] mmol; and Schirmer test, 23.73[21.28-26.18] mm. Lid margin was irregular in three eyes; 44.7% had thin lipid layer; lissamine green staining was positive in 70.8%; fluorescein staining was positive in 47.4%; 36.64% exhibited partial meibomian gland loss. CONCLUSION: Considering the scarcity of specific pediatric values of ocular surface tests, we performed a clinical investigation involving the complete pool of ocular surface tests in children. Although healthy children were included in this study, we found that all the participants had at least one abnormal result and 33.33% had dry eye disease diagnosis, according to the TFOS DEWS II. It would be relevant to carry out further multicentric studies to compare our ocular surface tests' results with other groups of children.

13.
Health Place ; 59: 102162, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31351378

RESUMEN

To assess the association between acute exposure to neighborhood violent crimes and depression we combined representative, individual-level and geo-coded data for individuals aged 60 years and above living in four major cities in Colombia from the 2010 Demographic and Health Survey (DHS) with objective information on the timing and location of violent crimes. Exploiting spatial and temporal variation in the occurrence of crimes we find that being acutely exposed to a violent crime is positively associated with the number of depressive symptoms.


Asunto(s)
Crimen/psicología , Depresión/etiología , Exposición a la Violencia/psicología , Características de la Residencia/estadística & datos numéricos , Anciano , Colombia/epidemiología , Crimen/estadística & datos numéricos , Depresión/epidemiología , Exposición a la Violencia/estadística & datos numéricos , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
14.
Environ Pollut ; 244: 477-485, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30366295

RESUMEN

In this study, we carried out high time-resolution measurements of particle number concentration and size distribution (5-1000 nm) in Singapore, which represents a tropical urban environment. The measurements were taken during the southwest monsoon season in 2017 using a fast-response differential mobility spectrometer at a sampling rate of 1 Hz. In the measurement, short-lived nucleation events were found prominent at early afternoon because of the abundant incoming radiation that enhances the photochemical reactions in atmosphere. For the first time in the region, a five-factor positive matrix factorization approach was applied to the size spectra data. Based on particle number concentration, two sources within nucleation mode (<30 nm) were resolved and account for 43% of total number concentration, which is higher than the available monitoring data in other big cities. Among the sources, O3-related atmospheric photochemical reactions with peak size at 10-12 nm is a unique factor and prominent in early afternoon nucleation events. The findings of this work can serve as a baseline for assessing influence of local and cross-border airborne emissions during various seasons in the future.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Emisiones de Vehículos/análisis , Atmósfera/análisis , Polvo/análisis , Humanos , Tamaño de la Partícula , Estaciones del Año , Singapur , Clima Tropical
15.
Int J Public Health ; 64(5): 703-711, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31119303

RESUMEN

ABSTARCT: OBJECTIVES: We analyzed the relation between exposure to the armed conflict and violence with mental health disorders in Colombia and assessed the extent and determinants of socioeconomic inequalities in mental health related to differential exposure to the conflict and violence. METHODS: Regression and decomposition analyses were used in combination with the 2015 nationally representative Mental Health Survey (N = 10,853). Mental health disorders were assessed using the Self-Reporting Questionnaire (SRQ 20), and socioeconomic status by a Multidimensional Poverty Index. RESULTS: 3% of adults have been victim of a violent crime and 13% victim of the armed conflict. Victims of the armed conflict have 1.74 times higher odds (p < .05) of suffering mental health disorders compared to non-victims. Differential exposure to the armed conflict among lower socioeconomic groups explains 86% of total inequality in mental health disorders. CONCLUSIONS: Interventions that increase quality and access of mental health treatments among victims of the conflict will not only lead to improvements in mental health among victims but also significantly reduce inequalities in mental health in Colombia.


Asunto(s)
Conflictos Armados/psicología , Conflictos Armados/estadística & datos numéricos , Trastornos Mentales/epidemiología , Pobreza/psicología , Pobreza/estadística & datos numéricos , Violencia/psicología , Violencia/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colombia/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoinforme , Clase Social , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
16.
Chem Sci ; 10(5): 1342-1350, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30809349

RESUMEN

A metastable "high-pressure" phase known as α-PbO2-type TiO2 or TiO2-II is prepared via a single-step synthesis using a laminar premixed stagnation flame. Three other TiO2 polymorphs, namely anatase, rutile and TiO2-B phases, can also be obtained by tuning the oxygen/fuel ratio. TiO2-II is observed as a mixture with rutile under oxygen-lean flame conditions. To the best of our knowledge, this is the first time that this phase has been identified in flame-synthesised TiO2. The formation of TiO2-II in an atmospheric pressure flame cannot be explained thermodynamically and is hypothesised to be kinetically driven through the oxidation and solid-state transformation of a sub-oxide TiO2-x intermediate. In this scenario, rutile is nucleated from the metastable TiO2-II phase instead of directly from a molten/amorphous state. Mixtures containing three-phase heterojunctions of anatase, rutile, and TiO2-II nanoparticles as prepared here in slightly oxygen-lean flames might be important in photocatalysis due to enhanced electron-hole separation.

17.
Rev Colomb Obstet Ginecol ; 70(1): 39-48, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-31613069

RESUMEN

OBJECTIVE: To get an insight into the structure and dynamics of the original families of five teenage mothers through their life stories and their own experiences. METHODS: Qualitative study with a narrative approach based on the life stories of five teenage mothers delivered at Engativá Hospital. Semistructured interviews were used to gain insight into the organization and structure of their original families. Emerging categories were identified by means of text hermeneutics, and results were validated using triangulation across researchers. RESULTS: The nuclear families of the pregnant women interviewed were characterized by the inability to deal with conflict appropriately, separations, structuring of new homes, confusion regarding roles, and matriarchal authority; reconstituted homes where the girls lived their own lives on the edge, where little value was attached to education, and where sexual and affective education were ambiguous and contradictory; families with expulsive dynamics where the teenage mother found herself having to survive on her own. CONCLUSIONS: Our pregnant adolescents live in the midst of families with unfavorable structure and dynamics that prevent the nuclear family from responding appropriately to teenage pregnancy. Consequently, pregnancy is an unplanned and rarely desired outcome, and a situation in which the family just normalizes the pregnancy when it occurs. In this context, pregnant adolescents are the result of a chain of inequities, where schooling is not valued and competencies for coping with life cannot grow fully to become an input for development. The noticeable resilience of one of the participants points to the need to undertake new studies focusing on identifying those traits of the individual, the family and the couple that increase their ability to adapt to the new situation.


TITULO: HISTORIAS DE VIDA FAMILIAR EN MADRES ADOLESCENTES: ESTUDIO CUALITATIVO REALIZADO EN EL HOSPITAL ENGATIVÁ ESE EN BOGOTÁ, COLOMBIA. OBJETIVO: Indagar en los relatos personales de cinco madres adolescentes inmersas en sus historias de vida y la vivencia de estas. METODOS: Estudio de tipo cualitativo con enfoque narrativo, mediante historias de vida de cinco mujeres adolescentes a quienes se les atendió su parto en el Hospital Engativá; mediante entrevistas semiestructuradas se indagó sobre la organización y la dinámica familiar de sus familias de origen. Mediante la hermenéutica del texto se identificaron categorías emergentes y se validaron los resultados por medio de triangulación de investigadores. RESULTADOS: Los núcleos familiares de las mujeres gestantes entrevistadas se caracterizaron por el mal manejo del conflicto, por las separaciones, por la estructuración de nuevos hogares y por la confusión en el ejercicio de roles, con una autoridad de tipo matriarcal; hogares reconstituidos donde las adolescentes orbitaban para hacer sus vidas; donde se daba un menor valor a la escolarización y en los que la educación de la sexualidad y la afectividad fueron ambiguas y contradictorias; familias con dinámicas expulsivas donde la madre adolescente debió enfrentarse al mundo de la supervivencia. CONCLUSIONES: Las adolescentes embarazadas del estudio desarrollan su vida en familias con una estructura y una dinámica poco propicia, que no les permite reaccionar adecuadamente a la adolescencia. De esta manera, el embarazo es una resultante no planeada y pocas veces deseada, situación en la que la familia se limita a normalizarlo cuando este se presenta. En este contexto, las adolescentes gestantes son el resultado de una serie de inequidades, donde la escolaridad tiene un menor valor y el desarrollo de competencias para la vida no alcanza a completarse como insumo para el desarrollo. Se destaca la capacidad resiliente de una de las participantes, lo que invita a nuevos estudios que permitan identificar aquellos elementos personales, de la familia y de la pareja que incrementen la capacidad de adaptación a esta nueva situación.


Asunto(s)
Conducta del Adolescente/psicología , Relaciones Familiares/psicología , Madres/psicología , Embarazo en Adolescencia/psicología , Adolescente , Colombia , Conflicto Familiar/psicología , Femenino , Humanos , Entrevistas como Asunto , Embarazo , Investigación Cualitativa
18.
Can J Gastroenterol Hepatol ; 2019: 3926051, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31929980

RESUMEN

Background: Gastroesophageal reflux disease (GERD) is the most frequent chronic gastrointestinal disorder. It is defined as a condition developed when the reflux of gastric contents causes troublesome symptoms (heartburn and regurgitation). This requires adequate treatment since it can lead to long-term complications including esophagus adenocarcinoma. Proton pump inhibitors (PPI) are generally used to treat GERD due to their high-security profile and efficiency on most patients. However, recurrent reflux despite initial treatment is frequent. N-of-1 trial is a study that allows the identification of the best treatment for each patient. The objective of this study is to compare the efficacy of standard dose with double dosage of esomeprazole, to improve the GERD symptoms in a single patient. Methods: A single-patient trial, placebo-controlled, randomized, double-blind, was carried out from September 25th, 2012, to April 26th, 2013. It included one outpatient at the gastroenterology service in a fourth-level hospital, diagnosed with nonerosive reflux disease (NERD). Yet, his symptoms were heartburn and reflux, and his endoscopic results were normal esophageal mucosa, without hiatal hernia, though pathological pH values. A no-obese male without any tobacco or alcohol usage received esomeprazole 40 mg/day and 40 mg/bid for 24 weeks. A standardized gastroesophageal reflux disease questionnaire (GerdQ) was used weekly to evaluate symptom frequency and severity. The consumption of 90% of the capsules was considered as an adequate treatment adherence. D'agostino-Pearson and Wilcoxon test were used to determine normal or nonnormal distribution and compare both treatments, respectively, both with a significant statistical difference of p < 0.05. Results: The patient completed the study with 96% of adherence. The double dosage of esomeprazole did not improve the control of symptoms compared with the standard dosage. Mean symptomatic score was 9.5±0.5 and 10.2±0.6 for each treatment, respectively (p > 0.05). Conclusion: There was no significant improvement in the patient GERD symptoms increasing the dose of oral esomeprazole during the 6 months of study. N-of-1 trials in chronic pathologies including GERD are recommended due to their potential value as systematic methods that evaluate therapies without strong scientific evidence.


Asunto(s)
Esomeprazol/administración & dosificación , Reflujo Gastroesofágico/tratamiento farmacológico , Inhibidores de la Bomba de Protones/administración & dosificación , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Proyectos de Investigación , Resultado del Tratamiento
19.
Brain Res ; 1123(1): 101-11, 2006 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-17045971

RESUMEN

The ventral division of the reticular oral pontine nucleus (vRPO) is a pontine tegmentum region critically involved in REM sleep generation. Previous reports of morphine microinjections in the cat pontine tegmentum have shown that opioid receptor activation in this region modulates REM sleep. Even though opiate administration has marked effects on sleep-wake cycle architecture, the distribution of opioid receptors in vRPO has only been partially described. Using an antiserum directed against delta opioid receptor (DOR), to which morphine binds, in the present study, we use (1) light microscopy to determine DOR cellular distribution in the rostral pontine tegmentum and (2) electron microscopy to determine DOR subcellular distribution in the cat vRPO. In the dorsal pons, DOR immunoreactivity was evenly distributed throughout the neuropil of the reticular formation and was particularly intense in the parabrachial nuclei and locus coeruleus; the ventral and central areas of the RPO and locus coeruleus complex were especially rich in DOR-labeled somata. Within the vRPO, DOR was localized mainly in the cytoplasm and on plasma membranes of medium to large dendrites (47.8% of DOR-labeled profiles), which received both symmetric and asymmetric synaptic contacts mainly from non-labeled (82% of total inputs) axon terminals. Less frequently, DOR was distributed presynaptically in axon terminals (19% of DOR-labeled profiles). Our results suggest that DOR activation in vRPO regulates REM sleep occurrence by modulating postsynaptic responses to both excitatory and inhibitory afferents. DOR activation in vRPO could have, however, an additional role in direct modulation of neurotransmitter release from axon terminals.


Asunto(s)
Neurópilo/ultraestructura , Receptores Opioides delta/metabolismo , Formación Reticular/metabolismo , Formación Reticular/ultraestructura , Animales , Gatos , Inmunohistoquímica , Neurópilo/metabolismo , Receptores Opioides delta/ultraestructura , Sueño REM/fisiología , Sinapsis/metabolismo , Sinapsis/ultraestructura , Distribución Tisular
20.
Am J Clin Pathol ; 123(1): 16-20, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15762275

RESUMEN

Immunohistochemical analysis is used routinely to determine the estrogen receptor (ER) status of breast cancers in paraffin sections. However, lack of standardization has raised concerns that weakly ER+ tumors often are classified erroneously as ER-. To determine the frequency of weakly ER+ tumors, we reviewed ER immunostains of 825 breast cancers. For each case, we estimated the proportion of ER+ tumor cells and also determined an Allred score (which results in scores of 0 or 2 through 8, based on staining intensity and proportion of positive cells). In 817 cases (99.0%), tumor cells showed complete absence of staining or staining in 70% or more of the cells. Similarly, 818 cases (99.2%) exhibited Allred scores of 0 or of 7 or 8. Thus, with the immunohistochemical method used in our laboratory, ER staining is essentially bimodal. The overwhelming majority of breast cancers are either completely ER- or unambiguously ER+, and cases with weak ER immunostaining are rare.


Asunto(s)
Neoplasias de la Mama/química , Inmunohistoquímica/métodos , Receptores de Estrógenos/análisis , Femenino , Humanos , Coloración y Etiquetado
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA