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1.
Breast Cancer Res Treat ; 202(1): 129-137, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37584883

RESUMO

PURPOSE: High-risk breast pathology is a breast cancer risk factor for which timely treatment is crucial. Nurse navigation programs have been implemented to minimize delays in patient care. This study evaluated nurse navigation in terms of timeliness to surgery for patients with high-risk breast pathology. METHODS: This was a single-institution, retrospective review of patients with identified high-risk breast pathology undergoing lumpectomy between January 2017 and June 2019. Patients were stratified into cohorts based on periods with and without nurse navigation. Preoperative and postoperative time to care as well as demographic and tumor characteristics were compared using univariate and multivariate analysis. RESULTS: 100 patients had assigned nurse navigators and 29 patients did not. Nurse navigation was associated with reduced time from referral to date of surgery (DOS) by 16.9 days (p = 0.003). Patients > 75 years had a shorter time to first appointment (p = 0.03), and patients with Medicare insurance had a reduced time from referral to DOS (p = 0.005). 20% of all patients were upstaged to cancer on final surgical pathology. CONCLUSION: Nurse navigation was significantly associated with decreased time to care for patients with high-risk breast pathology undergoing lumpectomy. We recommend nurse navigation programs as part of a comprehensive approach for patients with high-risk breast pathology.


Assuntos
Neoplasias da Mama , Navegação de Pacientes , Humanos , Idoso , Estados Unidos , Feminino , Medicare , Neoplasias da Mama/cirurgia , Encaminhamento e Consulta , Estudos Retrospectivos
2.
Artigo em Inglês | MEDLINE | ID: mdl-37227853

RESUMO

OBJECTIVE: Non-White sexual minorities experience disproportionate adverse childhood experiences (ACEs) and adulthood discrimination, as compared to their White or heterosexual counterparts. These stressors lead to increased psychological distress and worsened clinical outcomes, including suicidality. Minority stress theory posits that systemic marginalization, as experienced by minoritized individuals, leads to distress. Intersectionality theory suggests that marginalization compounds over time for individuals with intersectional minority identities. Yet, the mechanisms underlying the stress proliferation process for individuals with intersectional minority identities remain largely unexamined. METHOD: The present study used nationally representative data of sexual minority individuals (n = 1,518, Mage = 31 years, ethnoracial minority = 38.7%, female and gender minority = 50.6%) to investigate the relations among ethnoracial minoritization, ACEs, discrimination, distress, and self-injurious/suicidal outcomes. We proposed a novel integration of minority stress, intersectionality, and stress proliferation theories. Via longitudinal mediation, we tested models of stress persistence, stress accumulation, and stress sensitization. RESULTS: Our results confirmed disparities between White versus non-White sexual minorities on ACEs, discrimination experiences, and psychological distress. We found support for the stress persistence and the stress accumulation models, but not the stress sensitization model. Moreover, we found distress and discrimination were associated with future nonsuicidal self-injurious behaviors and suicidal outcomes, highlighting the deleterious consequences of intersectional minority stress proliferation. CONCLUSION: Our results support our proposed theory of intersectional minority stress proliferation where ethnoracial and sexual minoritization intersect and beget disproportionate ACEs, which in turn contribute to accumulation and persistence of psychological distress and discrimination experiences in adulthood. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

3.
Dev Psychopathol ; : 1-10, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37218034

RESUMO

BACKGROUND: Traditionally, depression phenotypes have been defined based on interindividual differences that distinguish between subgroups of individuals expressing distinct depressive symptoms often from cross-sectional data. Alternatively, depression phenotypes can be defined based on intraindividual differences, differentiating between transitory states of distinct symptoms profiles that a person transitions into or out of over time. Such within-person phenotypic states are less examined, despite their potential significance for understanding and treating depression. METHODS: The current study used intensive longitudinal data of youths (N = 120) at risk for depression. Clinical interviews (at baseline, 4, 10, 16, and 22 months) yielded 90 weekly assessments. We applied a multilevel hidden Markov model to identify intraindividual phenotypes of weekly depressive symptoms for at-risk youth. RESULTS: Three intraindividual phenotypes emerged: a low-depression state, an elevated-depression state, and a cognitive-physical-symptom state. Youth had a high probability of remaining in the same state over time. Furthermore, probabilities of transitioning from one state to another did not differ by age or ethnoracial minority status; girls were more likely than boys to transition from a low-depression state to either the elevated-depression state or the cognitive-physical symptom state. Finally, these intraindividual phenotypes and their dynamics were associated with comorbid externalizing symptoms. CONCLUSION: Identifying these states as well as the transitions between them characterizes how symptoms of depression change over time and provide potential directions for intervention efforts.

4.
Behav Res Ther ; 111: 44-51, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30300779

RESUMO

Previous research has linked sleep disturbance to anxiety. However, evidence for this relation has been inconsistent, largely limited to retrospective reports that do not account for daily variability, and silent on when the association is most pronounced. Thus, the present study utilized ecological momentary assessment (EMA) to examine the effects of daily deviations in total sleep time (TST) and person-average TST on anxiety and whether these effects varied as a function of time of day in a sample of unselected adults (N = 138). Results indicate that the amount of TST on a given night, relative to personal average TST, negatively predicted anxiety, and this relation was significant in the morning and afternoon, but not evening. In contrast, person-average TST was unrelated to average anxiety. Relations between TST and anxiety did not differ across objective (e.g., actigraphy) and subjective (e.g., sleep diary) measures. Furthermore, the pattern of results remained the same when controlling for previous day's anxiety and were not bidirectional. These findings suggest that getting less sleep than is typical for the individual predicts subsequent anxiety, and this effect is particularly strong in the morning. Average sleep duration may be less important to the experience of anxiety than deviations from that average. These findings highlight the importance of EMA to examine how and when variability in sleep confers vulnerability for anxiety symptoms.


Assuntos
Ansiedade/psicologia , Fotoperíodo , Sono , Actigrafia , Adolescente , Adulto , Avaliação Momentânea Ecológica , Feminino , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Adulto Jovem
5.
Am J Epidemiol ; 187(6): 1269-1276, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860470

RESUMO

The self-controlled tree-temporal scan statistic-a new signal-detection method-can evaluate whether any of a wide variety of health outcomes are temporally associated with receipt of a specific vaccine, while adjusting for multiple testing. Neither health outcomes nor postvaccination potential periods of increased risk need be prespecified. Using US medical claims data in the Food and Drug Administration's Sentinel system, we employed the method to evaluate adverse events occurring after receipt of quadrivalent human papillomavirus vaccine (4vHPV). Incident outcomes recorded in emergency department or inpatient settings within 56 days after first doses of 4vHPV received by 9- through 26.9-year-olds in 2006-2014 were identified using International Classification of Diseases, Ninth Revision, diagnosis codes and analyzed by pairing the new method with a standard hierarchical classification of diagnoses. On scanning diagnoses of 1.9 million 4vHPV recipients, 2 statistically significant categories of adverse events were found: cellulitis on days 2-3 after vaccination and "other complications of surgical and medical procedures" on days 1-3 after vaccination. Cellulitis is a known adverse event. Clinically informed investigation of electronic claims records of the patients with "other complications" did not suggest any previously unknown vaccine safety problem. Considering that thousands of potential short-term adverse events and hundreds of potential risk intervals were evaluated, these findings add significantly to the growing safety record of 4vHPV.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/efeitos adversos , Vigilância de Evento Sentinela , Adolescente , Adulto , Criança , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Incidência , Pacientes Internados/estatística & dados numéricos , Masculino , Infecções por Papillomavirus/virologia , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
6.
Molecules ; 24(1)2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30597869

RESUMO

Silicalite is an important nanoporous material that finds applications in several industries, including gas separation and catalysis. While the sorption, structure, and dynamics of several molecules confined in the pores of silicalite have been reported, most of these studies have been restricted to low pressures. Here we report a comparative study of sorption, structure, and dynamics of CO2 and ethane in silicalite at high pressures (up to 100 bar) using a combination of Monte Carlo (MC) and molecular dynamics (MD) simulations. The behavior of the two fluids is studied in terms of the simulated sorption isotherms, the positional and orientational distribution of sorbed molecules in silicalite, and their translational diffusion, vibrational spectra, and rotational motion. Both CO2 and ethane are found to exhibit orientational ordering in silicalite pores; however, at high pressures, while CO2 prefers to reside in the channel intersections, ethane molecules reside mostly in the sinusoidal channels. While CO2 exhibits a higher self-diffusion coefficient than ethane at low pressures, at high pressures, it becomes slower than ethane. Both CO2 and ethane exhibit rotational motion at two time scales. At both time scales, the rotational motion of ethane is faster. The differences observed here in the behavior of CO2 and ethane in silicalite pores can be seen as a consequence of an interplay of the kinetic diameter of the two molecules and the quadrupole moment of CO2.


Assuntos
Dióxido de Carbono/química , Etano/química , Simulação de Dinâmica Molecular , Pressão , Adsorção , Cinética , Estrutura Molecular , Método de Monte Carlo , Temperatura
7.
Cell ; 159(2): 333-45, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25284152

RESUMO

In the thymus, high-affinity, self-reactive thymocytes are eliminated from the pool of developing T cells, generating central tolerance. Here, we investigate how developing T cells measure self-antigen affinity. We show that very few CD4 or CD8 coreceptor molecules are coupled with the signal-initiating kinase, Lck. To initiate signaling, an antigen-engaged T cell receptor (TCR) scans multiple coreceptor molecules to find one that is coupled to Lck; this is the first and rate-limiting step in a kinetic proofreading chain of events that eventually leads to TCR triggering and negative selection. MHCII-restricted TCRs require a shorter antigen dwell time (0.2 s) to initiate negative selection compared to MHCI-restricted TCRs (0.9 s) because more CD4 coreceptors are Lck-loaded compared to CD8. We generated a model (Lck come&stay/signal duration) that accurately predicts the observed differences in antigen dwell-time thresholds used by MHCI- and MHCII-restricted thymocytes to initiate negative selection and generate self-tolerance.


Assuntos
Autoantígenos/imunologia , Tolerância Imunológica , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Cinética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Cadeias de Markov , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T/metabolismo , Timócitos/citologia , Timócitos/imunologia
8.
Vaccine ; 31 Suppl 10: K98-112, 2013 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-24331080

RESUMO

BACKGROUND: The Post-Licensure Rapid Immunization Safety Monitoring (PRISM) program is the immunization safety monitoring component of FDA's Mini-Sentinel project, a program to actively monitor the safety of medical products using electronic health information. FDA sought to assess the surveillance capabilities of this large claims-based distributed database for vaccine safety surveillance by characterizing the underlying data. METHODS: We characterized data available on vaccine exposures in PRISM, estimated how much additional data was gained by matching with select state and local immunization registries, and compared vaccination coverage estimates based on PRISM data with other available data sources. We generated rates of computerized codes representing potential health outcomes relevant to vaccine safety monitoring. Standardized algorithms including ICD-9 codes, number of codes required, exclusion criteria and location of the encounter were used to obtain the background rates. RESULTS: The majority of the vaccines routinely administered to infants, children, adolescents and adults were well captured by claims data. Immunization registry data in up to seven states comprised between 5% and 9% of data for all vaccine categories with the exception of 10% for hepatitis B and 3% and 4% for rotavirus and zoster respectively. Vaccination coverage estimates based on PRISM's computerized data were similar to but lower than coverage estimates from the National Immunization Survey and Healthcare Effectiveness Data and Information Set. For the 25 health outcomes of interest studied, the rates of potential outcomes based on ICD-9 codes were generally higher than rates described in the literature, which are typically clinically confirmed cases. CONCLUSION: PRISM program's data on vaccine exposures and health outcomes appear complete enough to support robust safety monitoring.


Assuntos
Coleta de Dados/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Vigilância de Produtos Comercializados/métodos , Vigilância de Evento Sentinela , Vacinação/efeitos adversos , Vacinas/administração & dosagem , Vacinas/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Processamento Eletrônico de Dados/métodos , Humanos , Revisão da Utilização de Seguros , Classificação Internacional de Doenças , Estados Unidos , United States Food and Drug Administration , Vacinação/estatística & dados numéricos
9.
N Engl J Med ; 367(15): 1428-37, 2012 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23050526

RESUMO

BACKGROUND: In October 2008, the Centers for Medicare and Medicaid Services (CMS) discontinued additional payments for certain hospital-acquired conditions that were deemed preventable. The effect of this policy on rates of health care-associated infections is unknown. METHODS: Using a quasi-experimental design with interrupted time series with comparison series, we examined changes in trends of two health care-associated infections that were targeted by the CMS policy (central catheter-associated bloodstream infections and catheter-associated urinary tract infections) as compared with an outcome that was not targeted by the policy (ventilator-associated pneumonia). Hospitals participating in the National Healthcare Safety Network and reporting data on at least one health care-associated infection before the onset of the policy were eligible to participate. Data from January 2006 through March 2011 were included. We used regression models to measure the effect of the policy on changes in infection rates, adjusting for baseline trends. RESULTS: A total of 398 hospitals or health systems contributed 14,817 to 28,339 hospital unit-months, depending on the type of infection. We observed decreasing secular trends for both targeted and nontargeted infections long before the policy was implemented. There were no significant changes in quarterly rates of central catheter-associated bloodstream infections (incidence-rate ratio in the postimplementation vs. preimplementation period, 1.00; P=0.97), catheter-associated urinary tract infections (incidence-rate ratio, 1.03; P=0.08), or ventilator-associated pneumonia (incidence-rate ratio, 0.99; P=0.52) after the policy implementation. Our findings did not differ for hospitals in states without mandatory reporting, nor did it differ according to the quartile of percentage of Medicare admissions or hospital size, type of ownership, or teaching status. CONCLUSIONS: We found no evidence that the 2008 CMS policy to reduce payments for central catheter-associated bloodstream infections and catheter-associated urinary tract infections had any measurable effect on infection rates in U.S. hospitals. (Funded by the Agency for Healthcare Research and Quality.).


Assuntos
Infecções Relacionadas a Cateter , Infecção Hospitalar , Economia Hospitalar , Hospitais/normas , Reembolso de Incentivo , Bacteriemia , Centers for Medicare and Medicaid Services, U.S. , Humanos , Medicaid/economia , Medicare/economia , Estados Unidos , Infecções Urinárias
10.
Am J Surg ; 204(4): 428-33, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22578407

RESUMO

BACKGROUND: Sentinel lymph node (SLN) biopsy is a staging technique for occult lymph node disease. SLN biopsy has been applied to select patients with sarcoma, although the clinical utility remains uncertain. METHODS: A PubMed/MEDLINE literature search was performed, and SLN biopsy outcomes were analyzed using a Bayesian meta-analytic approach to obtain point and interval estimates of rates of interest. RESULTS: Sixteen studies involving SLN biopsy in patients with sarcoma were identified. Of 114 patients reported, 14 patients had positive SLNs (crude estimate, 12%; meta-analysis estimate, 17%). The meta-analysis false-negative rate was 29% (95% credible interval, 5%-59%). Recurrence and death rates in the SLN-positive group were higher than in the SLN-negative group. CONCLUSIONS: This investigation highlights the current role of SLN biopsy in select patients with sarcoma for tumor staging. Questions regarding the high false-negative rate and management of micrometastatic lymphatic disease in patients with sarcoma still exist.


Assuntos
Linfonodos/patologia , Sarcoma/patologia , Biópsia de Linfonodo Sentinela , Teorema de Bayes , Reações Falso-Negativas , Humanos , Linfonodos/cirurgia , Metástase Linfática , Cadeias de Markov , Método de Monte Carlo , Rabdomiossarcoma/patologia , Sarcoma/cirurgia , Sarcoma de Células Claras/patologia , Sarcoma Sinovial/patologia
11.
Antivir Ther ; 12(7): 1027-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18018760

RESUMO

OBJECTIVES: HLA-B*5701 strongly predicts abacavir hypersensitivity (HSR), but implementation of effective routine screening into clinical practice requires testing be practical and accurate. We tested the proficiency of HLA-B*5701 typing among laboratories using sequence-specific primer PCR. DESIGN AND METHODS: DNA panels (1 and 2) were distributed to seven laboratories (A to G) for blinded typing of the HLA-B*5701 allele. Panel 1 (n = 10 samples; n = 7 laboratories) included 3 positives and other closely related B17 subtypes (B*5702, B*5703, B*5704 and B*5801). Panel 2 (n = 96 samples; n = 4 laboratories) included 36 positives among a broad spectrum of other B alleles. Two laboratories (A and B) also submitted 96 routine samples, typed by the same methodology, to the reference centre for additional analysis by sequence-based typing. RESULTS: All laboratories correctly typed panel 1 for HLA-B*5701 carriage. Laboratories A, B and C identified HLA-B*5701 alleles in panel 2 with 100% sensitivity and 100% specificity. Laboratory D reported one false negative, reportedly due to a sampling error. The results obtained for routine samples typed by laboratories A and B and those generated by the reference laboratory using sequencing were fully concordant. CONCLUSIONS: Detection of HLA-B*5701 alleles among laboratories was 100% specific and 99.4% sensitive, indicating that participating HIV testing laboratories were currently offering effective primary screening to identify individuals at high risk of abacavir HSR. Accurate reporting of HLA-B*5701 status is critical for the safe administration of this drug and participation in quality assurance programmes by all sites who report HLA-B*5701 status should be promoted.


Assuntos
Didesoxinucleosídeos/efeitos adversos , Testes Genéticos/normas , Antígenos HLA-B/genética , Alelos , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Primers do DNA , Sondas de DNA de HLA , Didesoxinucleosídeos/uso terapêutico , Hipersensibilidade a Drogas/genética , Humanos , Reação em Cadeia da Polimerase , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Clin Biochem ; 40(9-10): 585-90, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17493603

RESUMO

It is now 43 years since Berson and Yalow published the first radio-immunoassay (RIA) for parathyroid hormone (PTH) [S.A. Berson, R.S. Yalow, G.D. Aurbach, J.T. Potts, Immunoassay of bovine and human parathyroid hormone. Proc Natl Acad Sci U S A 49 (1963) 613-617] [1]. Since then, there have been marked advances in our understanding of this peptide hormone, its mechanism of action and biological regulation [J.T. Potts, Parathyroid hormone: past and present. J. Endocrinol. 187 (2005) 311-325] [2]. PTH has become a routine assay in tertiary care hospitals and is an essential element in the management of chronic kidney disease, parathyroid disorders and the investigation of abnormalities in calcium homeostasis. Despite continuing technological advances in PTH measurement, analyte heterogeneity remains a problem, while improved turnaround time and better precision are constantly escalating clinical demands. This mini-review begins with a brief update of current knowledge on PTH, followed by a summary of a recent Ontario-wide External Quality Assurance (EQA) survey, and concludes with comments on utilization trends, current and future.


Assuntos
Hormônio Paratireóideo , Humanos , Imunoensaio/normas , Cuidados Intraoperatórios/métodos , Medições Luminescentes/normas , Ontário , Hormônio Paratireóideo/análise , Hormônio Paratireóideo/fisiologia , Paratireoidectomia , Cuidados Pós-Operatórios/métodos , Controle de Qualidade
13.
J Abnorm Psychol ; 115(3): 428-42, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16866584

RESUMO

This study examined the relations between hassles and internalizing and externalizing symptoms across 4 years in adolescents who varied with regard to their risk for psychopathology. The sample comprised 240 adolescents assessed in 6th, 7th, 8th, and 9th grades regarding their level of peer and academic hassles and internalizing and externalizing symptoms. Structural equation modeling was used to construct latent variables of hassles and internalizing and externalizing syndromes. Results varied by informant about the teens' symptoms. For adolescent report, the stress exposure model fit the data best for internalizing syndromes; that is, higher levels of stressors predicted significantly higher levels of self-reported symptoms 1 year later. For mother report of adolescents' symptoms, the stress generation model fit the data best for both internalizing and externalizing syndromes; that is, higher levels of adolescents' internalizing and externalizing symptoms, as reported by their mothers, significantly predicted higher levels of hassles 1 year later.


Assuntos
Meio Ambiente , Acontecimentos que Mudam a Vida , Estresse Psicológico/psicologia , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores Socioeconômicos , Estresse Psicológico/diagnóstico , Inquéritos e Questionários
14.
Arthroscopy ; 21(7): 786-90, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16012490

RESUMO

PURPOSE: To compare the economic costs associated with anterior cruciate ligament (ACL) reconstruction using either autograft or allograft. The surgical costs are reported, including charge categories, for each procedure. All operations were performed in the Southern United States of America. TYPE OF STUDY: Evaluation of cost data collected from a group of patients participating in a prospective, nonrandomized trial. METHODS: A total of 122 patients with ACL-deficient knees undergoing surgical reconstruction using either bone-patellar tendon-bone autograft (n = 86) or freeze-dried Achilles tendon allograft (n = 37) were analyzed (1 patient underwent 2 allograft reconstructions). Patient selection for groups was based on the physician performing the surgery (2 surgeons performed autografts and 1 performed allografts). Groups were compared with respect to age, sex, race, and occupation. Hospital charge data were retrieved from the billing department and divided into various categories for comparison of the 2 groups. RESULTS: The mean hospital charge for ACL reconstruction was 4,622 dollars for allograft and 5,694 dollars for autograft (P < .0001). Differences included increased operating room time and a greater likelihood of overnight hospitalization for autograft procedures. This was slightly offset by higher charges for operating room supplies for allograft reconstructions owing to the cost of the graft itself. CONCLUSIONS: Allograft reconstruction of the ACL was significantly less expensive than autograft bone-patellar tendon-bone reconstruction. Allograft ACL reconstruction is a less costly alternative to autograft reconstruction. LEVEL OF EVIDENCE: Level IV, economic analysis with no sensitivity analysis.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Procedimentos de Cirurgia Plástica/economia , Adulto , Artroscopia/economia , Artroscopia/métodos , Osso e Ossos/cirurgia , Custos e Análise de Custo , Economia Hospitalar , Feminino , Humanos , Masculino , Patela/cirurgia , Estudos Retrospectivos , Transplante Autólogo/economia , Transplante Homólogo/economia , Estados Unidos
15.
Psychol Methods ; 10(1): 3-20, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15810866

RESUMO

The latent trait-state-error model (TSE) and the latent state-trait model with autoregression (LST-AR) represent creative structural equation methods for examining the longitudinal structure of psychological constructs. Application of these models has been somewhat limited by empirical or conceptual problems. In the present study, Monte Carlo analysis revealed that TSE models tend to generate improper solutions when N is too small, when waves are too few, and when occasion factor stability is either too large or too small. Mathematical analysis of the LST-AR model revealed its limitation to constructs that become more highly auto-correlated over time. The trait-state-occasion model has fewer empirical problems than does the TSE model and is more broadly applicable than is the LST-AR model.


Assuntos
Pesquisa Empírica , Psicologia/métodos , Humanos , Computação Matemática , Método de Monte Carlo
16.
Lancet Oncol ; 5(10): 607-16, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15465464

RESUMO

Metastatic bone disease is common in cancer patients and causes substantial disease-related morbidity and mortality. However, several effective treatments are available for the management of these patients. Bisphosphonates, which inhibit osteoclast-mediated resorption of bone matrix, are especially important because they decrease the incidence of skeletal-related events in many tumour types and can complement antineoplastic therapies. At present, assessment of treatment for bone metastases is hindered by a lack of effective, rapid methods to measure disease response. We discuss the difficulties of current measures of response assessment and describe the development of new radiological and biochemical markers of bone metastases. Assays that detect type I collagen telopeptides as markers of bone resorption seem to be most promising at present.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Absorciometria de Fóton , Biomarcadores Tumorais/sangue , Remodelação Óssea , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Resultado do Tratamento
17.
Gynecol Oncol ; 85(3): 397-403, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12051865

RESUMO

OBJECTIVE: Prophylactic oophorectomy (PO) is an accepted treatment strategy for women who are at high risk for the development of ovarian carcinoma, particularly women who are BRCA mutation-positive. This study sought to assess the utility of peritoneal lavage cytology at the time of PO in detecting occult malignancy in this group of patients. METHODS: Thirty-five high-risk women, who were not suspected of having any malignancy or ovarian mass, underwent peritoneal lavage at the time of PO. Thirty-one of the thirty-five women had undergone BRCA mutation analysis (BRCA1+, 18; BRCA2+, 10; BRCA-, 3). Intensive histopathologic examination was used in all 35 cases to identify occult carcinoma. Lavage specimens were reviewed for the presence of malignant cells and endosalpingiosis. The cytologic review was conducted without knowledge of either the histopathologic or BRCA results. RESULTS: In 32 of the 35 lavage specimens no malignancy was detected. In the remaining three cases malignant cells were detected; in two of these cases histopathologic examination confirmed an ovarian/tubal occult carcinoma. Two of these women were BRCA1 mutation positive. Endosalpingiosis was detected in the peritoneal lavage specimens of 7 of the 32 cases showing no evidence of malignancy. All of these 7 women were BRCA mutation positive or unknown. CONCLUSION: Peritoneal lavage cytology can detect occult carcinoma at the time of PO and should be performed at PO. The significance of occult carcinoma detected by either histopathologic or cytopathologic examination is uncertain. Whether the prevalence of endosalpingiosis detectable by lavage cytology is increased in BRCA mutation-positive patients requires further study.


Assuntos
Líquido Ascítico/patologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/prevenção & controle , Ovariectomia/métodos , Cistadenocarcinoma Seroso/patologia , Feminino , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Neoplasias Primárias Desconhecidas/patologia , Neoplasias Ovarianas/genética , Lavagem Peritoneal/métodos , Neoplasias Peritoneais/patologia
18.
MAGMA ; 13(3): 177-85, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11755094

RESUMO

Modern magnetic resonance imaging (MRI) systems consist of several complex, high cost subsystems. The cost and complexity of these systems often makes them impractical for use as routine laboratory instruments, limiting their use to hospitals and dedicated laboratories. However, advances in the consumer electronics industry have led to the widespread availability of inexpensive radio-frequency integrated circuits with exceptional abilities. We have developed a small, low-cost MR system derived from these new components. When combined with inexpensive desktop magnets, this type of MR scanner has the promise of becoming standard laboratory equipment for both research and education. This paper describes the development of a prototype desktop MR scanner utilizing a 0.21 T permanent magnet with an imaging region of approximately 2 cm diameter. The system uses commercially available components where possible and is programmed in LabVIEW software. Results from 3D data sets of resolution phantoms and fixed, newborn mice demonstrate the capability of this system to obtain useful images from a system constructed for approximately $13,500.


Assuntos
Campos Eletromagnéticos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Magnetismo , Animais , Animais Recém-Nascidos , Computadores , Desenho de Equipamento , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/economia , Camundongos , Imagens de Fantasmas , Software
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