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1.
Community Dent Health ; 39(3): 191-196, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35852232

RESUMEN

OBJECTIVES: Inequalities have been reported between high, middle and low socioeconomic position (SEP) children. However, the effect of contextual and individual SEP on existing inequalities among socioeconomically deprived children varies between local contexts. The aim of this study was to assess the impact of contextual and individual SEP on individual caries experience among socioeconomically deprived children in Chile. METHODS: Cross-sectional multilevel analysis of data from the 2015 electronic register of the National Board of School Aid and Scholarships (JUNAEB) of Chile. The contextual variables were the municipality Human Development Index (HDI) and rurality index. Individual variables included gender, living in extreme poverty and school grade. Multilevel negative binomial models assessed their impact on DMFT/dmft. RESULTS: 112,429 children in 255 municipalities were included. Overall, contextual SEP (HDI) was not associated with caries experience in the primary or permanent dentition. Individual SEP (living in extreme poverty) was associated with caries experience in both dentitions. The proportion of children living in extreme poverty with caries experience in the primary teeth was 17% higher than children not living in extreme poverty (PR 1.17; 95% CI 1.15-1.19), while for children with permanent teeth it was 9% higher (PR 1.09; 95% CI 1.08-1.11). CONCLUSION: These findings could support the development of health strategies focused on individual SEP to efficiently reduce oral health inequalities among socioeconomically deprived children.


Asunto(s)
Caries Dental , Niño , Estudios Transversales , Índice CPO , Caries Dental/epidemiología , Humanos , Análisis Multinivel , Salud Bucal , Pobreza , Prevalencia , Factores Socioeconómicos
2.
Phys Chem Chem Phys ; 22(27): 15321-15332, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32628225

RESUMEN

Conjugated carbon nanorings exhibit unique photophysical properties that, combined with their tunable sizes and conformations, make them suitable for a variety of practical applications. These properties are intimately associated to their strained, bent and sterically hindered cyclic structures. Herein we perform a comparative analysis of the photoinduced dynamics in carbon nanorings composed of nine phenyl units([9]CPP) and nine naphthyl units ([9]CN) respectively. The sterically demanding naphthyl units lead to large dihedral angles between neighboring units. Nevertheless, the ultrafast electronic and vibrational energy relaxation and redistribution is found to be similar for both systems. We observe that vibronic couplings, introduced by nonadiabatic energy transfer between electronic excited states, ensure the intramolecular vibrational energy redistribution through specific vibrational modes. The comparative impact of the internal conversion process on the exciton spatial localization and intra-ring migration indicates that naphthyl units in [9]CN achieve more efficient but less dynamical self-trapping compared to that of phenyl units in [9]CPP. That is, during the photoinduced process, the exciton in [9]CN is more static and localized than the exciton in [9]CPP. The internal conversion processes take place through a specific set of middle- to high-frequency normal modes, which directly influence the spatial exciton redistribution during the internal conversion, self-trapping and intra-ring migration.

3.
Int Nurs Rev ; 67(4): 453-465, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32779196

RESUMEN

AIM: To explore nursing and midwifery managers' views regarding obstacles to compassion-giving across country cultures. BACKGROUND: The benefit of compassionate leadership is being advocated, but despite the fact that health care is invariably conducted within culturally diverse workplaces, the interconnection of culture, compassion and leadership is rarely addressed. Furthermore, evidence on how cultural factors hinder the expression of compassion among nursing and midwifery managers is lacking. METHODS: Cross-sectional, exploratory, international online survey involving 1 217 participants from 17 countries. Managers' responses on open-ended questions related to barriers for providing compassion were entered and thematically analysed through NVivo. RESULTS: Three key themes related to compassion-giving obstacles emerged across countries: 1. related to the managers' personal characteristics and experiences; 2. system-related; and 3. staff-related. CONCLUSIONS: Obstacles to compassion-giving among managers vary across countries. An understanding of the variations across countries and cultures of what impedes compassion to flourish in health care is important. IMPLICATIONS FOR NURSING PRACTICE AND POLICY: Nursing mangers should wisely use their power by adopting leadership styles that promote culturally competent and compassionate workplaces with respect for human rights. Policymakers should identify training and mentoring needs to enable the development of managers' practical wisdom. Appropriate national and international policies should facilitate the establishment of standards and guidelines for compassionate leadership, in the face of distorted organizational cultures and system-related obstacles to compassion-giving.


Asunto(s)
Empatía , Partería , Estudios Transversales , Femenino , Humanos , Liderazgo , Embarazo , Encuestas y Cuestionarios
4.
J Antimicrob Chemother ; 74(4): 1108-1115, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30590545

RESUMEN

BACKGROUND: Infection diagnosis can be challenging, relying on clinical judgement and non-specific markers of infection. We evaluated a supervised machine learning (SML) algorithm for diagnosing bacterial infection using routinely available blood parameters on presentation to hospital. METHODS: An SML algorithm was developed to classify cases into infection versus no infection using microbiology records and six available blood parameters (C-reactive protein, white cell count, bilirubin, creatinine, ALT and alkaline phosphatase) from 160203 individuals. A cohort of patients admitted to hospital over a 6 month period had their admission blood parameters prospectively inputted into the SML algorithm. They were prospectively followed up from admission to classify those who fulfilled clinical case criteria for a community-acquired bacterial infection within 72 h of admission using a pre-determined definition. Predictive ability was assessed using receiver operating characteristics (ROC) with cut-off values for optimal sensitivity and specificity explored. RESULTS: One hundred and four individuals were included prospectively. The median (range) cohort age was 65 (21-98) years. The majority were female (56/104; 54%). Thirty-six (35%) were diagnosed with infection in the first 72 h of admission. Overall, 44/104 (42%) individuals had microbiological investigations performed. Treatment was prescribed for 33/36 (92%) of infected individuals and 4/68 (6%) of those with no identifiable bacterial infection. Mean (SD) likelihood estimates for those with and without infection were significantly different. The infection group had a likelihood of 0.80 (0.09) and the non-infection group 0.50 (0.29) (P < 0.01; 95% CI: 0.20-0.40). ROC AUC was 0.84 (95% CI: 0.76-0.91). CONCLUSIONS: An SML algorithm was able to diagnose infection in individuals presenting to hospital using routinely available blood parameters.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Infecciones/diagnóstico , Admisión del Paciente , Aprendizaje Automático Supervisado , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Biomarcadores , Toma de Decisiones Clínicas , Estudios de Cohortes , Pruebas Diagnósticas de Rutina/métodos , Manejo de la Enfermedad , Femenino , Estudios de Seguimiento , Pruebas Hematológicas , Humanos , Infecciones/epidemiología , Infecciones/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Adulto Joven
5.
Exp Cell Res ; 372(2): 85-91, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30248328

RESUMEN

Cell biology considers most animal tissues as assemblies of "individual" cells that rely on different contact-dependent communication mechanisms, including synapses, gap junctions or - a recent awareness - membrane nano- and microtubes. However, by protease-mediated singularization of dense 2D/ 3D cell cultures and tissue explants, we show here that cell collectives stay connected via a continuous meshwork of F-actin-based membrane tubes, resembling tunneling nanotube (TNT)-based networks observed between dispersed cell cultures. Fusion of respective tubes was accompanied by the ingrowth of microtubules and the invasion of mitochondria and lysosomes. Remarkably, in homology to the plasmodesmata-based plant symplast, we found evidence for expanded, membrane-based syncytia in animal tissues by observing dye transfer among the highly interlinked cells. This approach allows for the first time to visualize and quantify membrane continuity-based connections among densely packed cells and to assess their potential physiological and pathological impact closer to the in vivo situation.


Asunto(s)
Citoesqueleto de Actina/genética , Comunicación Celular/genética , Células Gigantes/fisiología , Péptido Hidrolasas/química , Citoesqueleto de Actina/fisiología , Actinas/genética , Actinas/fisiología , Animales , Comunicación Celular/fisiología , Estructuras de la Membrana Celular/genética , Estructuras de la Membrana Celular/fisiología , Fibroblastos/fisiología , Uniones Comunicantes/genética , Uniones Comunicantes/fisiología , Morfogénesis/genética , Morfogénesis/fisiología , Nanotubos/química , Ratas , Sinapsis/genética , Sinapsis/fisiología
6.
Anim Genet ; 50(4): 347-357, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31257665

RESUMEN

Durability traits in Thoroughbred horses are heritable, economically valuable and may affect horse welfare. The aims of this study were to test the hypotheses that (i) durability traits are heritable and (ii) genetic data may be used to predict a horse's potential to have a racecourse start. Heritability for the phenotype 'number of 2- and 3-year-old starts' was estimated to be h m 2  = 0.11 ± 0.02 (n = 4499). A genome-wide association study identified SNP contributions to the trait. The neurotrimin (NTM), opioid-binding protein/cell adhesion molecule like (OPCML) and prolylcarboxypeptidase (PRCP) genes were identified as candidate genes associated with the trait. NTM functions in brain development and has been shown to have been selected during the domestication of the horse. PRCP is an established expression quantitative trait locus involved in the interaction between voluntary exercise and body composition in mice. We hypothesise that variation at these loci contributes to the motivation of the horse to exercise, which may influence its response to the demands of the training and racing environment. A random forest with mixed effects (RFME) model identified a set of SNPs that contributed to 24.7% of the heritable variation in the trait. In an independent validation set (n = 528 horses), the cohort with high genetic potential for a racecourse start had significantly fewer unraced horses (16% unraced) than did low (27% unraced) potential horses and had more favourable race outcomes among those that raced. Therefore, the information from SNPs included in the model may be used to predict horses with a greater chance of a racecourse start.


Asunto(s)
Caballos/genética , Caballos/fisiología , Animales , Estudio de Asociación del Genoma Completo , Modelos Biológicos , Fenotipo , Condicionamiento Físico Animal , Polimorfismo de Nucleótido Simple
7.
Rev Chil Pediatr ; 90(6): 649-656, 2019 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32186588

RESUMEN

INTRODUCTION: We analyze the effectiveness and safety of a specific analgosedation protocol for procedures, and eva luate the satisfaction of the health personnel with each procedure. PATIENTS AND METHOD: Prospective study of an analgosedation protocol for hospital procedures in children under 18 years of age, with an individualized strategy based on the patient's baseline situation, the type of procedure and the experience of the pediatrician responsible for the sedation. The following variables were recorded: diagnosis motivating the procedure, type of procedure, anthropometric data, allergies, medication, ASA status and baseline disease, fasting time, lung auscultation, temperature, oxygen saturation, res piratory rate, heart rate, blood pressure, sedation location, type of drug, dose, route of administra tion, Ramsay sedation scale, duration of sedation, type and treatment of adverse effects, presence of family members throughout the procedure, and patient satisfaction. RESULTS: 279 sedations were performed. The most commonly used drugs were nitrous oxide (62.7%) and midazolam (16.5%); the most commonly used routes of administration were the inhaled one (62.4%) and the intravenous one (15.8%). The satisfaction was high for the pediatrician (92.5%), the nurse (94.3%), the family (96.8%), and patients (93.6%), with a good correlation between them, and it was significantly lower when using midazolam and the nasal and oral routes. The adverse effects rate was 3.2%, and none was severe. CONCLUSIONS: The implementation of a specific analgosedation protocol for procedures in the hospital environment achieves high levels of effectiveness and safety, as well as a high level of satisfaction, both in family members and in health personnel.


Asunto(s)
Analgesia/métodos , Anestesia/métodos , Protocolos Clínicos , Satisfacción en el Trabajo , Satisfacción del Paciente , Pediatras/psicología , Analgesia/efectos adversos , Analgesia/psicología , Analgésicos no Narcóticos , Anestesia/efectos adversos , Anestesia/psicología , Niño , Preescolar , Familia/psicología , Humanos , Hipnóticos y Sedantes , Lactante , Midazolam , Óxido Nitroso , Personal de Enfermería en Hospital/psicología , Dolor Asociado a Procedimientos Médicos/prevención & control , Estudios Prospectivos
8.
J Environ Manage ; 206: 103-112, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29059565

RESUMEN

Applying ozone to the return flow in an activated sludge (AS) process is a way for reducing the residual solids production. To be able to extend the activated sludge models to the ozone-AS process, adequate prediction of the tri-atoms effects on the particulate COD fractions is needed. In this study, the biomass inactivation, COD mineralization, and solids dissolution were quantified in batch tests and dose-response models were developed as a function of the reacted ozone doses (ROD). Three kinds of model-sludge were used. S1 was a lab-cultivated synthetic sludge with two components (heterotrophs XH and XP). S2 was a digestate of S1 almost made by the endogenous residues, XP. S3 was from a municipal activated sludge plant. The specific ozone uptake rate (SO3UR, mgO3/gCOD.h) was determined as a tool for characterizing the reactivity of the sludges. SO3UR increased with the XH fraction and decreased with more XP. Biomass inactivation was exponential (e-ß.ROD) as a function of the ROD doses. The percentage of solids reduction was predictable through a linear model (CMiner + Ysol ROD), with a fixed part due to mineralization (CMiner) and a variable part from the solubilization process. The parameters of the models, i.e. the inactivation and the dissolution yields (ß, 0.008-0.029 (mgO3/mgCODini)-1 vs Ysol, 0.5-2.8 mg CODsol/mgO3) varied in magnitude, depending on the intensity of the scavenging reactions and potentially the compactness of the flocs for each sludge.


Asunto(s)
Ozono , Aguas del Alcantarillado , Biomasa , Eliminación de Residuos Líquidos
9.
Am J Transplant ; 17(11): 2911-2921, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28397388

RESUMEN

Solid organ transplant recipients have an elevated incidence of thyroid cancer. We evaluated a wide range of potential risk factors in a cohort of 229 300 U.S. solid organ transplant recipients linked with 15 stage/regional cancer registries (1987-2012). Incidence rate ratios (IRRs) were adjusted for age, sex, race/ethnicity, transplanted organ, year of transplantation, and time since transplantation. Hazard ratios (HRs) for death and/or graft failure were adjusted for age, sex, race/ethnicity, transplanted organ, and year of transplantation. After transplantation, 356 thyroid cancers were diagnosed. Thyroid cancer incidence was 2.50-fold higher in transplant recipients than the general population (95% confidence interval [CI] 2.25-2.77). Among recipients of different organs, kidney recipients had the highest incidence of thyroid cancer (IRR = 1.26, 95% CI 1.03-1.53). Elevated thyroid cancer incidence was associated with cholestatic liver disease/cirrhosis as an indication for liver transplantation (IRR = 1.69, 95% CI 1.09-2.63), hypertensive nephrosclerosis as an indication for kidney transplantation (IRR = 1.41, 95% CI 1.03-1.94), and longer prior dialysis among kidney recipients (5+ vs. <1 year, IRR = 1.92, 95% CI 1.32-2.80; p-trend <0.01). Posttransplantation diagnosis of thyroid cancer was associated with modestly increased risk of death (HR = 1.33, 95% CI 1.02-1.73). Overall, our results suggest that end-stage organ disease and longer duration of dialysis may contribute to higher thyroid cancer incidence in transplant recipients.


Asunto(s)
Trasplante de Órganos/efectos adversos , Diálisis Renal/estadística & datos numéricos , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/etiología , Adulto , Factores de Edad , Anciano , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Sistema de Registros , Factores de Riesgo , Receptores de Trasplantes , Estados Unidos/epidemiología
10.
J Water Health ; 15(1): 145-154, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28151447

RESUMEN

Ceramic pot filters (CPFs) are an effective means of household water treatment, but the characterization of CPF lifetimes is ongoing. This paper describes a lifetime field study in Guatemala which was made possible by a collaboration between researchers, CPF-using households, and local non-governmental organizations (NGOs). Disinfection data were collected periodically for two years using field coliform enumeration kits as were flow rate data with the assistance of NGO staff. Consumer acceptance was characterized by surveying householders in the four subject villages at the beginning and end of the study. Flow rate data showed that average CPF flow rates decreased below the recommended minimum of 1 L h-1 after 10 months of use; however, the survey results indicated that the consumers were tolerant of the lower flow rates, and it is reasonable to assume that the daily volume of treated water can be readily increased by refilling the CPFs more frequently. Of greater concern was the finding that disinfection efficacy decreased below the recommended bacterial reduction after 14 months of use because it would not be obvious to users that effectiveness had declined. Finally, the follow-up visits by the researchers and the NGO staff appeared to increase consumer acceptance of the CPFs.


Asunto(s)
Cerámica/análisis , Desinfección/métodos , Agua Potable/análisis , Filtración/métodos , Purificación del Agua/métodos , Desinfección/instrumentación , Filtración/instrumentación , Guatemala , Purificación del Agua/instrumentación
11.
Am J Transplant ; 16(12): 3479-3489, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27160653

RESUMEN

Renal cell carcinoma (RCC) is a common malignancy following kidney transplantation. We describe RCC risk and examine RCC risk factors among US kidney recipients (1987-2010). The Transplant Cancer Match Study links the US transplant registry with 15 cancer registries. Standardized incidence ratios (SIRs) were used to compare RCC risk (overall and for clear cell [ccRCC] and papillary subtypes) to the general population. Associations with risk factors were assessed using Cox models. We identified 683 RCCs among 116 208 kidney recipients. RCC risk was substantially elevated compared with the general population (SIR 5.68, 95% confidence interval 5.27-6.13), especially for papillary RCC (SIR 13.3 versus 3.98 for ccRCC). Among kidney recipients, RCC risk was significantly elevated for blacks compared to whites (hazard ratio [HR] 1.50) and lower in females than males (HR 0.56). RCC risk increased with prolonged dialysis preceding transplantation (p-trend < 0.0001). Risk was variably associated for RCC subtypes with some medical conditions that were indications for transplantation: ccRCC risk was reduced with polycystic kidney disease (HR 0.54), and papillary RCC was increased with hypertensive nephrosclerosis (HR 2.02) and vascular diseases (HR 1.86). In conclusion, kidney recipients experience substantially elevated risk of RCC, especially for papillary RCC, and multiple factors contribute to these cancers.


Asunto(s)
Carcinoma de Células Renales/etiología , Rechazo de Injerto/etiología , Neoplasias Renales/etiología , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias , Adulto , Carcinoma de Células Renales/epidemiología , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/epidemiología , Humanos , Incidencia , Fallo Renal Crónico/cirugía , Pruebas de Función Renal , Neoplasias Renales/epidemiología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Estados Unidos/epidemiología
12.
Am J Transplant ; 16(10): 2986-2993, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27062091

RESUMEN

US transplant centers are required to report cancers in transplant recipients to the transplant network. The accuracy and completeness of these data, collected in the Scientific Registry of Transplant Recipients (SRTR), are unknown. We compared diagnoses in the SRTR and 15 linked cancer registries for colorectal, liver, lung, breast, prostate and kidney cancers; melanoma; and non-Hodgkin lymphoma (NHL). Among 187 384 transplants, 9323 cancers were documented in the SRTR or cancer registries. Only 36.8% of cancers were in both, with 47.5% and 15.7% of cases additionally documented solely in cancer registries or the SRTR, respectively. Agreement between the SRTR and cancer registries varied (kappa = 0.28 for liver cancer and kappa = 0.52-0.66 for lung, prostate, kidney, colorectum, and breast cancers). Upon evaluation, some NHLs documented only in cancer registries were identified in the SRTR as another type of posttransplant lymphoproliferative disorder. Some SRTR-only cases were explained by miscoding (colorectal cancer instead of anal cancer, metastases as lung or liver cancers) or missed matches with cancer registries, partly due to recipients' outmigration from catchment areas. Estimated sensitivity for identifying cancer was 52.5% for the SRTR and 84.3% for cancer registries. In conclusion, SRTR cancer data are substantially incomplete, limiting their usefulness for surveillance and research.


Asunto(s)
Recolección de Datos/normas , Neoplasias/diagnóstico , Trasplante de Órganos , Sistema de Registros/normas , Adulto , Femenino , Humanos , Incidencia , Masculino , Neoplasias/epidemiología , Pronóstico , Estados Unidos/epidemiología
13.
BJOG ; 123(3): 427-36, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26259689

RESUMEN

OBJECTIVE: To generate a global reference for caesarean section (CS) rates at health facilities. DESIGN: Cross-sectional study. SETTING: Health facilities from 43 countries. POPULATION/SAMPLE: Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10,045,875 women giving birth from 43 countries for model testing. METHODS: We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. MAIN OUTCOME MEASURES: Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. RESULTS: According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). CONCLUSIONS: This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. TWEETABLE ABSTRACT: The C-Model provides a customized benchmark for caesarean section rates in health facilities and systems.


Asunto(s)
Cesárea/estadística & datos numéricos , Modelos Estadísticos , Adulto , Estudios Transversales , Femenino , Humanos , Internacionalidad , Embarazo , Valores de Referencia
14.
Phys Chem Chem Phys ; 18(9): 6955, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-26877266

RESUMEN

Correction for 'Miscibility studies of two twist-bend nematic liquid crystal dimers with different average molecular curvatures. A comparison between experimental data and predictions of a Landau mean-field theory for the NTB-N phase transition' by D. O. López et al., Phys. Chem. Chem. Phys., 2016, 18, 4394-4404.

15.
Phys Chem Chem Phys ; 18(6): 4394-404, 2016 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-26790976

RESUMEN

We report a calorimetric study of a series of mixtures of two twist-bend liquid crystal dimers, the 1'',7''-bis(4-cyanobiphenyl)-4'-yl heptane (CB7CB) and 1''-(2',4-difluorobiphenyl-4'-yloxy)-9''-(4-cyanobiphenyl-4'-yloxy) nonane (FFO9OCB), the molecules of which have different effective molecular curvatures. High-resolution heat capacity measurements in the vicinity of the NTB-N phase transition for a selected number of binary mixtures clearly indicate a first order NTB-N phase transition for all the investigated mixtures, the strength of which decreases when the nematic range increases. Published theories predict a second order NTB-N phase transition, but we have developed a self-consistent mean field Landau model using two key order parameters: a symmetric and traceless tensor for the orientational order and a short-range vector field which is orthogonal to the helix axis and rotates around of the heliconical structure with an extremely short periodicity. The theory, in its simplified form, depends on two effective elastic constants and explains satisfactorily our heat capacity measurements and also predicts a first-order NTB-N phase transition. In addition, as a complementary source of experimental measurements, the splay (K1) and bend (K3) elastic constants in the conventional nematic phase for the pure compounds and some selected mixtures have been determined.

16.
Ginecol Obstet Mex ; 84(3): 127-35, 2016 Mar.
Artículo en Español | MEDLINE | ID: mdl-27424438

RESUMEN

BACKGROUND: Metaplasic carcinoma of the breast was initially described by Huvos in 1974. It is a rare and aggressive entity characterized by the presence of mesenchymal and epithelial components. OBJECTIVE: To know the incidence and biologic behaviour of the metaplasic carcinoma of the breast at the Instituto de Enfermedades de la Mama, FUCAM, AC. METHODS: Data on women diagnosed with metaplasic carcinoma of the breast between January 2005 and December 2014 was collected by retrospectively reviewing in FUCAM. Clinical, pathological and immunohistochemical characteristics were assessed. The five-year disease-free survival (DFS) and overall survival (OS) were evaluated. RESULTS: a total of 4198 patients have been diagnosed with breast cancer in our institution, 40 (0.95%) of them with metaplasic carcinoma. The median age of the patients was 46 years (27-73). 60% of the patients were diagnosed with an advanced clinical stage (III) and the triple-negative subtype was the most frequently found. A mean follow-up of 24 months showed rates of overall survival and disease-free survival of 80% and 69.9%, respectively. The presence of both, cytokeratins 5/6 and p63, seems to have a negative impact in local recurrence. CONCLUSION: this study demonstrates that metaplasic carcinoma is a rare and aggressive disease. Expression of both tumor cytokeratins was associated with a worse outcome.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma/metabolismo , Queratina-5/biosíntesis , Queratina-6/biosíntesis , Factores de Transcripción/biosíntesis , Proteínas Supresoras de Tumor/biosíntesis , Adulto , Anciano , Neoplasias de la Mama/mortalidad , Carcinoma/mortalidad , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
17.
Cir Pediatr ; 29(4): 171-174, 2016 Oct 10.
Artículo en Español | MEDLINE | ID: mdl-28481071

RESUMEN

OBJECTIVES: To assess the long-term evolution of the testicles preserved after testicular torsion (TT). MATERIAL AND METHODS: We realized a prospective study by ultrasound of patients diagnosed TT that underwent orchidopexy. We reviewed 85 patients treated for acute scrotum (2004-2014), finding 49TT. We excluded from the study 15 perinatal torsions, 14 orchiectomies and 5 patients who refused to participate. We analyzed 15 patients, comparing testicular volumes between affected and contralateral testes, and the difference in volume between the two testes of the 15 cases with 14 control patients (Mann-Whitney U test). RESULTS: 15 patients underwent surgery at a mean age of 10,7 years, with an average time of 6 hours evolution [0,7-24]. The control ultrasound was performed at a mean age of 14,7 years, after a mean time of 47 months after the episode, finding a medium volume of the affected and contralateral testicle of 9,3 cc and 12,6 cc, respectively (p = 0,683). The median of the difference between the volumes was 0'8 cc [0,1-12,80]. In the control group, ultrasounds were performed at a mean age of 16 years, with an average volume of 6,64 cc on right testicle and 6,26 cc on the left, and median volume difference of 0,34 cc [0,05-4,59]; with no statistically significant difference (p = 0,270) between testicular volume differences of cases and controls. CONCLUSION: Testicular orchidopexy in patients with TT with less than 6 hours of evolution does not affect the long-term testicular growth, compared with the contralateral testis growth and testes of the normal population.


OBJETIVOS: Valorar la evolución a largo plazo de los testículos preservados tras torsión testicular (TT). MATERIAL Y METODOS: Estudio prospectivo mediante ecografía de pacientes diagnosticados de TT a los que se les realizó detorsión y orquidopexia. Revisamos 85 pacientes intervenidos por escroto agudo (2004-2014), encontrando 49TT. Excluimos del estudio 15 torsiones perinatales, 14 orquiectomías y 5 pacientes que se negaron a participar. Analizamos 15 pacientes, comparando volúmenes testiculares entre testes afectos y contralaterales, y la diferencia de volúmenes entre ambos testes de los 15 casos con 14 pacientes control (prueba U de Mann-Whitney). RESULTADOS: Los 15 pacientes se intervinieron a una edad media de 10,7 años, con un tiempo medio de evolución de 6 horas [0,7-24]. La ecografía control se realizó a una edad media de 14,7 años, tras un tiempo medio de 47 meses después del episodio, encontrando unas medianas del volumen del teste torsionado y contralateral de 9,3 cc y 12,6 cc, respectivamente (p = 0,683). La mediana de la diferencia entre los volúmenes fue de 0,8 cc [0,1-12,80]. En el grupo control, las ecografías fueron realizadas a una edad media de 16 años, con media de volumen de teste izquierdo de 6,26 cc y derecho de 6,64 cc, y mediana de diferencia de volúmenes de 0,34 cc [0,05-4,59]; no encontrándose diferencias estadísticamente significativas (p = 0,270) entre las diferencias de volúmenes de los testículos de casos y controles. CONCLUSION: La detorsión testicular en pacientes con TT con un tiempo de evolución inferior a 6 horas no influye en el crecimiento testicular a largo plazo, comparado con el crecimiento del teste contralateral y de los testículos de la población normal.


Asunto(s)
Torsión del Cordón Espermático/cirugía , Testículo/diagnóstico por imagen , Adolescente , Niño , Humanos , Masculino , Orquidopexia , Estudios Prospectivos , Escroto , Torsión del Cordón Espermático/diagnóstico por imagen , Resultado del Tratamiento
18.
J Food Sci Technol ; 53(12): 4159-4167, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28115756

RESUMEN

This work examined changes in color that can be explained solely on the basis of the total myoglobin content and the relative proportions of deoxymyoglobin, oxymyoglobin (OMb) and metmyoglobin (MMb) during storage of meat. Meat color was evaluated for L*, a*, b*, C* and hab. Total pigment content was measured from the reflex attenuance at 525 nm (A525). The relative proportions of each pigment was determined using two different methods: the Krzywicki method based on the reflex attenuance values at 473, 525, 572 and 700 nm and the KS method based on K/S ratios of the absorption and scattering coefficients (K/S)474 ÷ (K/S)525, (K/S)572 ÷ (K/S)525 and (K/S)610 ÷ (K/S)525. The study was performed on beef (Longissimus lumborum) samples measured after 1, 4 and 7 days of exposure to air. Result revealed that L* values can be fully explained by A525 alone. C* and a* were well explained by those parameters related to OMb content. The other color parameters depended on pigment forms. The KS method gave better results. The parameters related to MMb content were relevant to classify samples according to the time of exposure to air. In any case, information provided by color and pigment parameters were complementary to each other.

19.
Kathmandu Univ Med J (KUMJ) ; 14(54): 112-119, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28166065

RESUMEN

Background Nepal is in the midst of a disease transition, including a rapid increase of noncommunicable diseases. In order for health policy makers and planners to make informed programmatic and funding decisions, they need up to date and accurate data regarding cause of death throughout the country. Methods of improving cause of death reporting in Nepal are urgently required. Objective We sought to validate SmartVA-Analyze, an application which computer certifies verbal autopsies, to evaluate it as a method for collecting mortality data in Nepal. Method We conducted a medical record review of mortality cases at Dhulikhel Hospital, Kathmandu University Hospital. Cases with a verifiable underlying cause of death were used as gold standard reference cases. Verbal autopsies were conducted with caregivers of 48 gold standard cases. Result Of the 66 adult gold standard mortality cases reviewed, 76% were caused by cancer, cirrhosis, cardiovascular disease, COPD or injury. When assessing concordance between cause of death from verbal autopsy vs. gold standards, we found an overall agreement (Kappa) of 0.50. Kappa based on broader ICD-10 categories was 0.69. Cause-Specific Mortality Fraction Accuracy was 0.625, and disease specific measures of concordance varied widely, with sensitivities ranging from 0-100%. Conclusion Ongoing, countrywide mortality data collection is crucial for evidence-based priority setting in Nepal. Though not valid for all causes, we found SmartVA-Analyze to provide useful general cause of death data, particularly in settings where death certification is unavailable.


Asunto(s)
Autopsia/estadística & datos numéricos , Causas de Muerte , Adulto , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Recolección de Datos , Femenino , Humanos , Masculino , Nepal/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Heridas y Lesiones/mortalidad
20.
J Opt Soc Am A Opt Image Sci Vis ; 32(2): 228-37, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26366594

RESUMEN

In this work we obtain general expressions for the complex refractive indices of refracted waves as a function of the angle of incidence in the case of an electromagnetic wave propagating in a transparent isotropic medium that reaches an interface with a biaxial absorbing medium. The biaxial absorbing medium is only required to have a diagonalizable complex dielectric tensor. Obtained expressions can be applied to any orientation of the principal axes and can be specialized for isotropic, uniaxial or biaxial, or transparent or absorbing media. By using these expressions we have also obtained the surface of indices and the surface of absorption coefficients for an example of a biaxial absorbing medium.

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