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1.
Arthrosc Tech ; 13(3): 102874, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38584631

RESUMEN

This article presents an adaptation of the internal brace ulnar collateral ligament (UCL) repair technique using knotless suture anchors, which shows promise for improved postsurgical functionality and a shortened recovery period in patients with UCL injuries. Traditional methods of UCL reconstruction often require a lengthy 12- to 18-month recovery period, presenting a significant challenge for athletes keen to return to their sport. The modified technique uses smaller sutures and drill holes, thereby eliminating the need for larger anchors and simplifying the surgical process. Furthermore, we provide a comprehensive exploration of the rehabilitation protocol involved after surgery, which includes various phases of physical therapy and use of the "thrower's ten" program to improve shoulder and elbow stability, strength, and mobility. This technique paves the way for a promising alternative to traditional UCL reconstruction or repair methods, with the potential to significantly enhance clinical outcomes, improve recovery times, and positively impact athletes' lives.

2.
J Orthop Surg Res ; 18(1): 442, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37340426

RESUMEN

INTRODUCTION: Open reduction internal fixation (ORIF) and intramedullary nail fixation (IMN) are the predominant repair methods for operative treatment of humeral diaphyseal fractures; however, the optimal method is not fully elucidated. The purpose of this study was to analyze whether IMN or ORIF humeral diaphyseal surgeries result in a significantly higher prevalence of adverse outcomes and whether these outcomes were age dependent. We hypothesize there is no difference in reoperation rates and complications between IMN and ORIF for humeral diaphyseal fractures. METHODS: Data collected from 2015 to 2017 from the Nationwide Readmissions Database were evaluated to compare the prevalence of six adverse outcomes: radial nerve palsy, infections, nonunion, malunion, delayed healing, and revisions. Patients treated for a primary humeral diaphyseal fracture with either IMN or ORIF were matched and compared (n = 2,804 pairs). Patients with metastatic cancer were excluded. RESULTS: Following an ORIF procedure, there was a greater odds of undergoing revision surgery (p = 0.03) or developing at least one of the complications of interest (p = 0.03). In the age-stratified analysis, no significant differences were identified in the prevalence of adverse outcomes between the IMN and ORIF cohorts in the 0-19, 20-39, and 40-59 age groups. Patients who were 60 + had 1.89 times the odds of experiencing at least one complication and 2.04 times the odds of undergoing a revision after an ORIF procedure versus an IMN procedure (p = 0.03 for both). DISCUSSION: IMN and ORIF for humeral diaphyseal fractures are comparable in regard to complications revision rates in patients under the age of 60. Meanwhile, patients 60 + years show a statistically significant increase in the odds of undergoing revision surgery or experiencing complications following an ORIF. Since IMN appears to be more beneficial to older patients, being 60 + years old should be considered when determining fracture repair techniques for patients presenting with primary humeral diaphyseal fractures.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas del Húmero , Humanos , Persona de Mediana Edad , Readmisión del Paciente , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Fijadores Internos/efectos adversos , Reducción Abierta/efectos adversos , Reducción Abierta/métodos , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Fracturas del Húmero/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Fijación Intramedular de Fracturas/métodos , Húmero , Resultado del Tratamiento , Estudios Retrospectivos , Placas Óseas/efectos adversos , Clavos Ortopédicos/efectos adversos
3.
J Orthop Trauma ; 37(8): e302-e306, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36952595

RESUMEN

BACKGROUND: Removal of orthopaedic intramedullary implants can be difficult and time-consuming. Instrumentation for implant removal is frequently deficient for effective removal. The purpose of this study was to compare the efficiency of a C-type jig with a standard slap hammer attachment. We hypothesize that a C-type jig will be a more energy-efficient method for implant removal. METHODS: An intramedullary (IM) nail removal was simulated in a series of 10 tests using 40 PCF Sawbones bone blocks with drilled holes and custom-made IM nails. Each attachment was secured to a Shukla Medical threaded connector from their IM nail revision product. A camera recorded each hammer swing, and a caliper recorded the distance the nail traveled out of the bone block. The data were then analyzed to determine extraction rate and efficiency. RESULTS: The c-frame hammer exerted a greater force, had a greater extraction efficiency, and required 37.4% less energy expenditure than the slap hammer to extract the nail the same distance. The c-frame hammer also removed the nail 38.1% faster with the same energy expenditure and possessed greater usable kinetic energy, whereas the slap hammer had more "lost" energy. CONCLUSIONS: The c-frame hammer attachment was found to have a considerably higher extraction rate and efficiency than the slap hammer. It will be a more useful method of implant extraction, especially for cases involving larger bones or larger implants. However, the slap hammer may be more suitable for smaller tools or bones for which larger impact loading would be detrimental.


Asunto(s)
Clavos Ortopédicos , Fijación Intramedular de Fracturas , Humanos , Fijación Intramedular de Fracturas/métodos , Fijación Interna de Fracturas , Tornillos Óseos , Remoción de Dispositivos
4.
J Shoulder Elb Arthroplast ; 7: 24715492231152146, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36727143

RESUMEN

Introduction: Total elbow arthroplasty (TEA) is an increasingly popular surgical option for many debilitating conditions of the elbow. There currently exists a paucity of literature regarding patient and hospital factors that lead to inferior outcomes following TEA. The purpose of this study is to identify independent predictors of increased complication and revision rates following TEA. Methods: The National Readmissions Database (NRD) was queried from 2011 to 2018 to identify all cases of TEA (n = 8932). Relevant patient demographic factors, comorbidities, and hospital characteristics were identified and run in a univariate binomial logistic regression model. All significant variables were included in a multivariate binomial logistic regression model for data analysis. Results: Independent predictors of increased complication rates included age, female sex, Medicare and Medicaid payer status, medium bed-sized center, and 18 of 34 medical comorbidities (all P < .05). Independent predictors of increased revision rates included medium bed-sized centers, non-teaching hospital status, chronic pulmonary disease, depression, and pulmonary circulatory disorders (all P < .05). Conclusion: This study identified several patient and hospital characteristics that are independently associated with both increased complication and revision rates following TEA. This information can aid orthopedic surgeons during shared decision making when considering TEA in patients. Level of Evidence: Level III, retrospective cohort study.

5.
Psychol Assess ; 34(10): 952-965, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35980696

RESUMEN

The growth of school-based initiatives incorporating multitiered systems of support (MTSS) for social, emotional, and behavioral domains has fueled interest in behavioral assessment. These assessments are foundational to determining risk for behavioral difficulties, yet research to date has been limited with regard to when and how often to administer them. The present study evaluated these questions within the framework of behavioral stability and examined the extent to which behavior is stable when measured by two school-based behavioral assessments: the Direct Behavior Rating-Single-Item Scales (DBR-SIS), and the Behavioral and Emotional Screening System (BESS). Participants included 451 students rated three times per year across 4 years, with the primary teacher from each year providing the within-year ratings. Latent variable models were employed to measure the constructs underlying the observed assessment scores. Models demonstrated that the DBR-SIS best captured changes within the year, whereas the BESS scores remained stable across time points within a year. Across years, scores from both assessments captured changes. The unique contributions of each assessment in the data-based decision-making process are discussed, and recommendations are given for their combined use within and across school years. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Conducta Infantil , Instituciones Académicas , Escala de Evaluación de la Conducta , Niño , Conducta Infantil/psicología , Humanos , Tamizaje Masivo , Estudiantes/psicología
6.
Environ Eng Sci ; 38(5): 389-401, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34079210

RESUMEN

Individuals experiencing unsheltered homelessness face significant barriers to accessing water, sanitation, and hygiene services, but the risks associated with this lack of access and barriers to service provision have been largely understudied. We analyzed water samples upstream and downstream of three homeless encampments in the San Diego River watershed and interviewed service providers from public and nonprofit sectors to assess local perceptions about challenges and potential solutions for water and sanitation service provision in this context. Water upstream from encampments contained detectable levels of caffeine and sucralose. Escherichia coli concentrations downstream of the encampments were significantly greater than concentrations upstream, but there was no significant change in the concentrations of other pollutants, including caffeine and sucralose. The HF183 marker of Bacteroides was only detected in one sample upstream of an encampment and was not detected downstream. Overall, there was insufficient evidence to suggest that the encampments studied here were responsible for contributing pollution to the river. Nevertheless, the presence of caffeine, sucralose, and HF183 indicated that there are anthropogenic sources of contamination in the river during dry weather and potential risks associated with the use of this water by encampment residents. Interviews with service providers revealed perceptions that the provision of water and sanitation services for this population would be prohibitively expensive. Interviewees also reported perceptions that most riverbank residents avoided contact with service providers, which may present challenges for the provision of water and sanitation service unless trust is first built between service providers and residents of riverine encampments.

7.
Artículo en Inglés | MEDLINE | ID: mdl-33669672

RESUMEN

Homelessness is a persistent problem in the United States in general and in Southern California especially. While progress has been made in reducing the number of people experiencing homelessness in the United States from 2007 (647,000) to 2019 (567,000), it remains an entrenched problem. The purpose of this paper is to outline a novel, interdisciplinary academic-practice partnership model to address homelessness. Where singular disciplinary approaches may fall short in substantially reducing homelessness at the community and population level, our model draws from a collective impact model which coordinates discipline-specific approaches through mutually reinforcing activities and shared metrics of progress and impact to foster synergy and sustainability of efforts. This paper describes the necessary capacity-building at the institution and community level for the model, the complementary strengths and contributions of each stakeholder discipline in the proposed model, and future goals for implementation to address homelessness in the Southern California region.


Asunto(s)
Personas con Mala Vivienda , Creación de Capacidad , Humanos , Estados Unidos
8.
Sch Psychol Q ; 34(1): 43-53, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29792497

RESUMEN

Responsive service delivery frameworks rely on the use of screening approaches to identify students in need of support and to guide subsequent assessment and intervention efforts. However, limited empirical investigations have been directed to informing how often screening should occur for social, emotional, and behavioral difficulties in school settings. The purpose of the current study was to evaluate the stability of risk status on 3 different screening instruments across 3 administrations across the course of a school year. A total of 1,594 students had complete screening data across 3 time points, corresponding to a total of 187 teachers from 22 different public schools located within the northeastern and midwestern United States. Across measures, we examined patterns of risk across time points and investigated the utility of (a) different screening schedules (fall, winter, and spring) and (b) borderline screening when conducting multiple screenings per year. Results indicated that a large proportion of students exhibited stable risk patterns across time points and suggested that borderline screening may be a viable alternative for schools with limited resources. Implications for practice and future research are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Conducta Infantil/psicología , Estudiantes/psicología , Adolescente , Niño , Trastornos de la Conducta Infantil/psicología , Femenino , Humanos , Masculino , Tamizaje Masivo , Factores de Riesgo , Instituciones Académicas
9.
J Sch Psychol ; 68: 53-72, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29861031

RESUMEN

Reliable and valid data form the foundation for evidence-based practices, yet surprisingly few studies on school-based behavioral assessments have been conducted which implemented one of the most fundamental approaches to construct validation, the multitrait-multimethod matrix (MTMM). To this end, the current study examined the reliability and validity of data derived from three commonly utilized school-based behavioral assessment methods: Direct Behavior Rating - Single Item Scales, systematic direct observations, and behavior rating scales on three common constructs of interest: academically engaged, disruptive, and respectful behavior. Further, this study included data from different sources including student self-report, teacher report, and external observers. A total of 831 students in grades 3-8 and 129 teachers served as participants. Data were analyzed using bivariate correlations of the MTMM, as well as single and multi-level structural equation modeling. Results suggested the presence of strong methods effects for all the assessment methods utilized, as well as significant relations between constructs of interest. Implications for practice and future research are discussed.


Asunto(s)
Conducta del Adolescente/psicología , Conducta Infantil/psicología , Estudiantes/psicología , Adolescente , Niño , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Instituciones Académicas
10.
Psychol Assess ; 29(1): 98-109, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27099978

RESUMEN

Counterbalancing treatment order in experimental research design is well established as an option to reduce threats to internal validity, but in educational and psychological research, the effect of varying the order of multiple tests to a single rater has not been examined and is rarely adhered to in practice. The current study examines the effect of test order on measures of student behavior by teachers as raters utilizing data from a behavior measure validation study. Using multilevel modeling to control for students nested within teachers, the effect of rating an earlier measure on the intercept or slope of a later behavior assessment was statistically significant in 22% of predictor main effects for the spring test period. Test order effects had potential for high stakes consequences with differences large enough to change risk classification. Results suggest that researchers and practitioners in classroom settings using multiple measures evaluate the potential impact of test order. Where possible, they should counterbalance when the risk of an order effect exists and report justification for the decision to not counterbalance. (PsycINFO Database Record


Asunto(s)
Conducta Infantil , Maestros , Estudiantes/psicología , Adolescente , Niño , Emociones , Humanos , Masculino , Trastornos Mentales , Problema de Conducta , Habilidades Sociales
11.
J Sch Psychol ; 54: 39-57, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26790702

RESUMEN

The implementation of multi-tiered systems in schools necessitates the use of screening assessments which produce valid and reliable data to identify students in need of tiered supports. Data derived from these screening assessments may be evaluated according to their classification accuracy, or the degree to which cut scores correctly identify individuals as "at-risk" or "not-at-risk." The current study examined the performance of mean scores derived from over 1700 students in Grades 1, 2, 4, 5, 7, and 8 using Direct Behavior Rating-Single Item Scales. Students were rated across three time points (Fall, Winter, Spring) by their teachers in three areas: (a) academically engaged behavior, (b) disruptive behavior, and (c) respectful behavior. Classification accuracy indices and comparisons among behaviors were derived using Receiver Operating Characteristic (ROC) curve analyses, partial area under the curve (pAUC) tests, and bootstrapping methods to evaluate the degree to which mean behavior ratings accurately identified students who demonstrated elevated behavioral symptomology on the Behavioral and Emotional Screening System. Results indicated that optimal cut-scores for mean behavior ratings and a composite rating demonstrated high levels of specificity, sensitivity, and negative predictive value, with sensitivity point estimates for optimal cut-scores exceeding .70 for individual behaviors and .75 for composite scores across grade groups and time points.


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Conducta Infantil/psicología , Instituciones Académicas , Estudiantes/psicología , Niño , Trastornos de la Conducta Infantil/psicología , Femenino , Humanos , Masculino , Tamizaje Masivo
12.
Sch Psychol Q ; 30(2): 184-196, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25111469

RESUMEN

The purpose of this study was to examine the relation between teacher-implemented screening measures used to identify social, emotional, and behavioral risk. To this end, 5 screening options were evaluated: (a) Direct Behavior Rating - Single Item Scales (DBR-SIS), (b) Social Skills Improvement System - Performance Screening Guide (SSiS), (c) Behavioral and Emotional Screening System - Teacher Form (BESS), (d) Office discipline referrals (ODRs), and (e) School nomination methods. The sample included 1974 students who were assessed tri-annually by their teachers (52% female, 93% non-Hispanic, 81% white). Findings indicated that teacher ratings using standardized rating measures (DBR-SIS, BESS, and SSiS) resulted in a larger proportion of students identified at-risk than ODRs or school nomination methods. Further, risk identification varied by screening option, such that a large percentage of students were inconsistently identified depending on the measure used. Results further indicated weak to strong correlations between screening options. The relation between broad behavioral indicators and mental health screening was also explored by examining classification accuracy indices. Teacher ratings using DBR-SIS and SSiS correctly identified between 81% and 91% of the sample as at-risk using the BESS as a criterion. As less conservative measures of risk, DBR-SIS and SSiS identified more students as at-risk relative to other options. Results highlight the importance of considering the aims of the assessment when selecting broad screening measures to identify students in need of additional support.


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Emociones , Adolescente , Niño , Diagnóstico Precoz , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Servicios de Salud Escolar , Estudiantes/psicología , Estados Unidos
13.
J Sch Psychol ; 52(1): 13-35, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24495492

RESUMEN

Generalizability Theory (GT) offers increased utility for assessment research given the ability to concurrently examine multiple sources of variance, inform both relative and absolute decision making, and determine both the consistency and generalizability of results. Despite these strengths, assessment researchers within the fields of education and psychology have been slow to adopt and utilize a GT approach. This underutilization may be due to an incomplete understanding of the conceptual underpinnings of GT, the actual steps involved in designing and implementing generalizability studies, or some combination of both issues. The goal of the current article is therefore two-fold: (a) to provide readers with the conceptual background and terminology related to the use of GT and (b) to facilitate understanding of the range of issues that need to be considered in the design, implementation, and interpretation of generalizability and dependability studies. Given the relevance of this analytic approach to applied assessment contexts, there exists a need to ensure that GT is both accessible to, and understood by, researchers in education and psychology. Important methodological and analytical considerations are presented and implications for applied use are described.


Asunto(s)
Psicología Educacional , Proyectos de Investigación , Humanos , Psicometría , Reproducibilidad de los Resultados , Instituciones Académicas
14.
J Sch Psychol ; 52(1): 63-82, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24495495

RESUMEN

The purpose of this study was to evaluate the utility of Direct Behavior Rating Single Item Scale (DBR-SIS) targets of disruptive, engaged, and respectful behavior within school-based universal screening. Participants included 31 first-, 25 fourth-, and 23 seventh-grade teachers and their 1108 students, sampled from 13 schools across three geographic locations (northeast, southeast, and midwest). Each teacher rated approximately 15 of their students across three measures, including DBR-SIS, the Behavioral and Emotional Screening System (Kamphaus & Reynolds, 2007), and the Student Risk Screening Scale (Drummond, 1994). Moderate to high bivariate correlations and area under the curve statistics supported concurrent validity and diagnostic accuracy of DBR-SIS. Receiver operating characteristic curve analyses indicated that although respectful behavior cut scores recommended for screening remained constant across grade levels, cut scores varied for disruptive behavior and academic engaged behavior. Specific cut scores for first grade included 2 or less for disruptive behavior, 7 or greater for academically engaged behavior, and 9 or greater for respectful behavior. In fourth and seventh grades, cut scores changed to 1 or less for disruptive behavior and 8 or greater for academically engaged behavior, and remained the same for respectful behavior. Findings indicated that disruptive behavior was particularly appropriate for use in screening at first grade, whereas academically engaged behavior was most appropriate at both fourth and seventh grades. Each set of cut scores was associated with acceptable sensitivity (.79-.87), specificity (.71-.82), and negative predictive power (.94-.96), but low positive predictive power (.43-.44). DBR-SIS multiple gating procedures, through which students were only considered at risk overall if they exceeded cut scores on 2 or more DBR-SIS targets, were also determined acceptable in first and seventh grades, as the use of both disruptive behavior and academically engaged behavior in defining risk yielded acceptable conditional probability indices. Overall, the current findings are consistent with previous research, yielding further support for the DBR-SIS as a universal screener. Limitations, implications for practice, and directions for future research are discussed.


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Conducta Infantil/psicología , Instituciones Académicas , Estudiantes/psicología , Niño , Femenino , Humanos , Masculino , Tamizaje Masivo , Sensibilidad y Especificidad
15.
J Sch Psychol ; 51(3): 367-85, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23816230

RESUMEN

The purpose of this study was to investigate how Direct Behavior Rating Single Item Scales (DBR-SIS) involving targets of academically engaged, disruptive, and respectful behaviors function in school-based screening assessment. Participants included 831 students in kindergarten through eighth grades who attended schools in the northeastern United States. Teachers provided behavior ratings for a sample of students in their classrooms on the DBR-SIS, the Behavioral and Emotional Screening System (Kamphaus & Reynolds, 2007), and the Student Risk Screening Scale (Drummond, 1994). Given variations in rating procedures to accommodate scheduling differences across grades, analysis was conducted separately for elementary school and middle school grade levels. Results suggested that the recommended cut scores, the combination of behavior targets, and the resulting conditional probability indices varied depending on grade level grouping (lower elementary, upper elementary, middle). For example, for the lower elementary grade level grouping, a combination of disruptive behavior (cut score=2) and academically engaged behavior (cut score=8) was considered to offer the best balance among indices of diagnostic accuracy, whereas a cut score of 1 for disruptive behavior and 8 for academically engaged behavior were recommended for the upper elementary school grade level grouping and cut scores of 1 and 9, respectively, were suggested for middle school grade level grouping. Generally, DBR-SIS cut scores considered optimal for screening using single or combined targets including academically engaged behavior and disruptive behavior by offering a reasonable balance of indices for sensitivity (.51-.90), specificity (.47-.83), negative predictive power (.94-.98), and positive predictive power (.14-.41). The single target of respectful behavior performed poorly across all grade level groups, and performance of DBR-SIS targets was relatively better in the elementary school than middle school grade level groups. Overall, results supported that disruptive behavior is highly important in evaluating risk status in lower grade levels and that academically engaged behavior becomes more pertinent as students reach higher grade levels. Limitations, future directions, and implications are discussed.


Asunto(s)
Conducta del Adolescente/psicología , Conducta Infantil/psicología , Servicios de Salud Escolar , Instituciones Académicas , Estudiantes/psicología , Adolescente , Niño , Docentes , Femenino , Humanos , Masculino
16.
Sch Psychol Q ; 27(1): 41-50, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22582935

RESUMEN

This study presents an evaluation of the diagnostic accuracy and concurrent validity of Direct Behavior Rating Single Item Scales for use in school-based behavior screening of second-grade students. Results indicated that each behavior target was a moderately to highly accurate predictor of behavioral risk. Optimal universal screening cut scores were also identified for each scale, with results supporting reduced false positive rates through the simultaneous use of multiple scales.


Asunto(s)
Déficit de la Atención y Trastornos de Conducta Disruptiva/diagnóstico , Pruebas Psicológicas/normas , Medición de Riesgo , Servicios de Salud Escolar/normas , Estudiantes/psicología , Adolescente , Déficit de la Atención y Trastornos de Conducta Disruptiva/etnología , Déficit de la Atención y Trastornos de Conducta Disruptiva/prevención & control , Distribución de Chi-Cuadrado , Niño , Preescolar , Docentes/estadística & datos numéricos , Femenino , Humanos , Estudios Longitudinales , Masculino , Tamizaje Masivo , Pruebas Psicológicas/estadística & datos numéricos , Psicometría/instrumentación , Curva ROC , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Medición de Riesgo/normas , Distribución por Sexo , Facilitación Social , Participación Social/psicología , Factores Socioeconómicos , Estudiantes/estadística & datos numéricos , Factores de Tiempo
17.
Breast Cancer Res Treat ; 114(3): 549-58, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18437558

RESUMEN

OBJECTIVE: Many studies that have estimated the breast cancer risk attributable to family history have been based on data collected within family units. Use of this study design has likely overestimated risks for the general population. We provide population-based estimates of breast cancer risk and different tumor subtypes in relation to the degree, number, and age at diagnosis of affected relatives. METHODS: Cox Proportional Hazards to calculate risks (hazard ratios; 95% confidence interval) of breast cancer and tumor subtypes for women with a family history of breast cancer relative to women without a family history among a cohort of 75,189 women age >or=40 years of whom 1,087 were diagnosed with breast cancer from June 1, 2001-December 31, 2005 (median follow-up 3.16 years). RESULTS: Breast cancer risk was highest for women with a first-degree family history (1.54; 1.34-1.77); and did not differ substantially by the affected relative's age at diagnosis or by number of affected first-degree relatives. A second-degree family history only was not associated with a significantly increased breast cancer risk (1.15; 0.98-1.35). There was a suggestion that a positive family history was associated with risk of triple positive (Estrogen+/Progesterone+/HER2+) and HER2-overexpressing tumors. CONCLUSIONS: While a family history of breast cancer in first-degree relatives is an important risk factor for breast cancer, gathering information such as the age at diagnosis of affected relatives or information on second-degree relative history may be unnecessary in assessing personal breast cancer risk among women age >or=40 years.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , Estudios de Cohortes , Salud de la Familia , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Receptor ErbB-2/biosíntesis , Receptor ErbB-2/genética , Riesgo
18.
Exp Hematol ; 33(12): 1493-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16338492

RESUMEN

OBJECTIVE: Iron overload is a key contributor to the pathogenesis of multiple disorders including the sideroblastic anemias. The specific iron compounds present in tissues or cells that are the target of iron deposition remain poorly understood, but there is evidence that some forms are magnetically active. We have developed a simple and specific method to purify iron-overloaded red blood cells using magnetic affinity columns. Here we describe this method and characterize purified Sod2-deficient siderocytes. MATERIALS AND METHODS: RBC derived from mice transplanted with Sod2-deficient hematopoietic stem cells served as a source of iron-laden cells. Purification was based upon the observation that iron deposits in Sod2-deficient cells are "magnetically susceptible" and allow for retention of iron-laden cells in a strong magnetic field. Peripheral blood from Sod2-deficient chimeric mice was passed through magnetic separation columns; iron-overloaded cells were eluted and characterized by flow cytometry, Western blot, and microscopy. RESULTS: We were able to purify 2.8% of the total red cells as iron-laden siderocytes. The magnetically purified Sod2-deficient cells were predominantly identified as reticulocytes. They had numerous siderotic granules, produced enhanced levels of reactive oxygen species, and showed increased protein oxidative damage, mitochondrial enrichment, and mitochondrial hyperpolarization. CONCLUSIONS: Our method can be used to purify iron-laden cells as well as iron-associated subcellular fractions prepared from iron-loaded tissues, allowing elucidation of the structure, location, and protein composition of such iron deposits. This data will help develop our understanding of the pathogenesis of SA and other disorders characterized by iron overload.


Asunto(s)
Anemia Sideroblástica/sangre , Eritrocitos/patología , Separación Inmunomagnética/métodos , Sobrecarga de Hierro/sangre , Animales , Cromatografía de Afinidad , Hierro/metabolismo , Métodos , Ratones , Mitocondrias/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/deficiencia
19.
Blood ; 104(8): 2565-73, 2004 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-15205258

RESUMEN

SOD2 is an antioxidant protein that protects cells against mitochondrial superoxide. Hematopoietic stem cells (HSCs) lacking SOD2 are capable of rescuing lethally irradiated hosts, but reconstituted animals display a persistent hemolytic anemia characterized by increased oxidative damage to red cells, with morphologic similarity to human "sideroblastic" anemia. We report further characterization of this novel SOD2-deficiency anemia. Electron micrographs of SOD2-deficient reticulocytes reveal striking mitochondrial proliferation and mitochondrial membrane thickening. Peripheral blood smears show abundant iron-stainable granules in mature red cells (siderocytes). Fluorescence-activated cell sorting (FACS) analysis of cells labeled with oxidation-sensitive dyes demonstrates enhanced production of superoxide and hydrogen peroxide by SOD2-deficient cells. Oxidative damage to proteins is increased in SOD2-deficient cells, with much of the damage affecting membrane/insoluble proteins. Red cell proteome analysis demonstrates that several proteins involved in folding/chaperone function, redox regulation, adenosine triphosphate (ATP) synthesis, and red cell metabolism show altered expression in SOD2-deficient cells. This data, combined with information on how protein expression levels change upon antioxidant therapy, will aid in identification of proteins that are sensitive to oxidative damage in this model, and by extension, may have a role in the regulation of red cell lifespan in other hemolytic disorders.


Asunto(s)
Anemia/metabolismo , Anemia/patología , Antioxidantes/metabolismo , Regulación de la Expresión Génica , Estrés Oxidativo , Superóxido Dismutasa/deficiencia , Adenosina Trifosfato/metabolismo , Anemia/enzimología , Anemia/genética , Animales , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Médula Ósea/metabolismo , Médula Ósea/patología , Catálisis , Cloruros/metabolismo , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Eritrocitos/patología , Eritropoyesis , Peróxido de Hidrógeno/metabolismo , Transporte Iónico , Hierro/metabolismo , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Mitocondrias/patología , Oxidación-Reducción , Potasio/metabolismo , Proteómica , Protoporfirinas/metabolismo , Bazo/metabolismo , Bazo/patología , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo
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