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1.
Prev Sci ; 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477808

RESUMO

Current childhood obesity treatment programs do not address medically underserved populations or settings where all members of an interdisciplinary team may not exist-either within one organization or within the community. In this paper, we describe the use of a community-academic partnership to iteratively adapt Epstein's Traffic Light Diet (TLD), into Building Healthy Families (BHF), a community-placed evidence-based pediatric weight management intervention (PWMI) and evaluate its effectiveness in reducing BMI z scores. Nine cohorts of families completed BHF. Participants included children aged 6-12 years with obesity (M = 9.46, SD = 1.74). The Framework for Reporting Adaptations and Modifications-Expanded guided our classification of modifications across BHF cohorts. Using the FRAME reporting structure, the changes that were documented were (1) planned and occurred pre-implementation, (2) based on decisions from local stakeholders (e.g., school administrator, members of the implementation team), and (3) specific to changes in content and context-with a focus on implementation and potential for local scale-up. The nature of the adaptations included adding elements (whole of family approach), removing elements (calorie counting), and substituting elements (steps for minutes of physical activity). Across 9 cohorts, 84 families initiated the BHF program, 69 families successfully completed the 12-week program, and 45 families returned for 6-month follow-up assessments. Results indicated that the BMI z score in children was reduced by 0.31 ± 0.17 at 6 months across all cohorts. Reduction in BMI z score ranged from 0.41 in cohort 4 to 0.13 in cohort 5. Iterative adaptations to BHF were completed to improve the fit of BHF to the setting and participants and have contributed to a sustained community PWMI that adheres to the underlying principles and core elements of other evidence-based PWMIs. Monitoring adaptations and related changes to outcomes can play a role in long-term sustainability and effectiveness.

2.
Sci Adv ; 5(4): eaav3006, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30949578

RESUMO

Protected areas (PAs) are fundamental for biodiversity conservation, yet their impacts on nearby residents are contested. We synthesized environmental and socioeconomic conditions of >87,000 children in >60,000 households situated either near or far from >600 PAs within 34 developing countries. We used quasi-experimental hierarchical regression to isolate the impact of living near a PA on several aspects of human well-being. Households near PAs with tourism also had higher wealth levels (by 17%) and a lower likelihood of poverty (by 16%) than similar households living far from PAs. Children under 5 years old living near multiple-use PAs with tourism also had higher height-for-age scores (by 10%) and were less likely to be stunted (by 13%) than similar children living far from PAs. For the largest and most comprehensive socioeconomic-environmental dataset yet assembled, we found no evidence of negative PA impacts and consistent statistical evidence to suggest PAs can positively affect human well-being.


Assuntos
Conservação dos Recursos Naturais , Nível de Saúde , Saúde Pública , Biodiversidade , Países em Desenvolvimento , Ecossistema , Características da Família , Geografia , Saúde Global , Humanos , Modelos Teóricos
3.
Geohealth ; 1(6): 248-257, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32158990

RESUMO

Iron deficiency reduces capacity for physical activity, lowers IQ, and increases maternal and child mortality, impacting roughly a billion people worldwide. Recent studies have shown that certain highly consumed crops-C3 grains (e.g., wheat, rice, and barley), legumes, and maize-have lower iron concentrations of 4-10% when grown under increased atmospheric CO2 concentrations (550 ppm). We examined diets in 152 countries globally (95.5% of the population) to estimate the percentage of lost dietary iron resulting from anthropogenic CO2 emissions between now and 2050, specifically among vulnerable age-sex groups: children (1-5 years) and women of childbearing age (15-49 years), holding diets constant. We also cross-referenced these with the current prevalence of anemia to identify most at-risk countries. We found that 1.4 billion children aged 1-5 and women of childbearing age (59% of global total for these groups) live in high-risk countries, where the prevalence of anemia exceeds 20% and modeled loss in dietary iron would be in the most severe tertile (>3.8%). The countries with the highest anemia prevalence also derive their iron from the fewest number of foods, even after excluding countries consuming large amounts of unaccounted wild-harvest foods. The potential risk of increased iron deficiency adds greater incentive for mitigating anthropogenic CO2 emissions and highlights the need to address anticipated health impacts via improved health delivery systems, dietary behavioral changes, or agricultural innovation. Because these are effects on content rather than yield, it is unlikely that consumers will perceive this health threat and adapt to it without education.

4.
Proc Natl Acad Sci U S A ; 106(26): 10415-22, 2009 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-19556548

RESUMO

InfoMax and FastICA are the independent component analysis algorithms most used and apparently most effective for brain fMRI. We show that this is linked to their ability to handle effectively sparse components rather than independent components as such. The mathematical design of better analysis tools for brain fMRI should thus emphasize other mathematical characteristics than independence.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Simulação por Computador , Humanos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Radiografia , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador
5.
Child Care Health Dev ; 30(4): 385-94, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15191430

RESUMO

BACKGROUND: Despite the availability of effective screening measures, primary care providers continue to fail to identify and manage many children with psychosocial problems. One of the best predictors of identification by a primary care physician is whether mothers disclose concerns about their child's psychosocial functioning to their child's physician. This study examined if maternal distress and child behaviour predicted whether mothers had and discussed concerns about their child's behaviour and emotions with paediatricians. METHODS: Participants were 138 mothers who accompanied their 4-12-year-old children to a health supervision visit at an urban teaching hospital. Mothers completed a demographic questionnaire, the Pediatric Symptom Checklist, the Beck Depression Inventory, and an exit questionnaire. Results Logistic regression correctly classified 97.3% of mothers who did not disclose child problems. Only 34.5% of mothers who did disclose were correctly classified. CONCLUSIONS: The results supported the hypothesis that mothers' psychosocial functioning is significantly related to concern about child behaviour and disclosure of concerns to the paediatrician. The inability of child behaviour and maternal functioning to predict which mothers were concerned and disclosed concerns supports the hypothesis that disclosure and identification of psychosocial problems in primary care is complex and requires a multifactor model.


Assuntos
Transtornos do Comportamento Infantil/diagnóstico , Mães/psicologia , Adulto , Criança , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Revelação/tendências , Feminino , Humanos , Modelos Logísticos , Comportamento Materno/psicologia , Pessoa de Meia-Idade , Pediatria , Relações Profissional-Família , Psicologia da Criança , Inquéritos e Questionários
6.
Neurogastroenterol Motil ; 16 Suppl 1: 106-11, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15066014

RESUMO

Interstitial cells of Cajal (ICC) are involved in generation of gut pacemaker activity, neurotransmission and stretch sensation. Pacemaker ICC exhibit spontaneous cyclic calcium oscillations that are in synchrony with its pacemaker activity. The spontaneous rhythmic inward currents in ICC that underlie gut pacemaker activity are linked to this calcium oscillation. It is probable that more than one type of channel contributes to the inward current with a high conductance chloride channel and a nonselective cation channel being the main candidates. The activation of these channels is linked to intracellular calcium cycling mechanism and involves inositol 1,4,5-trisphosphate (IP3)-mediated calcium release from the sarcoplasmic reticulum, and calcium uptake into mitochondria. This ion channel activity is modulated by signalling through neurotransmitter receptors, including the NK1 receptor. This finding and the presence of other neurotransmitter receptor mRNA transcripts indicates that ion channels in ICC are targets for neurotransmitter action. The ether-a-go-go-related (ERG) K channel is probably the most important K channel contributing to the resting membrane potential and excitability of the ICC. Many ion channels in ICC are regulated by second messenger systems which makes them highly susceptible to neurotransmitter modulation.


Assuntos
Cálcio/metabolismo , Sistema Digestório/inervação , Canais Iônicos/fisiologia , Neurônios/metabolismo , Neurotransmissores/metabolismo , Animais , Relógios Biológicos/fisiologia , Humanos , Potenciais da Membrana/fisiologia
7.
Clin Psychol Rev ; 21(7): 1061-93, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11584516

RESUMO

The Conners' Parent Rating Scales (CPRS) have undergone a considerable amount of scrutiny--and subsequent refining, reshaping, and revising--since their development in 1970. While such longitudinal scrutiny has ultimately led to a more reliable, valid assessment tool, it has left behind a wake of literature filled with misinformation and ambiguity. Multiple versions of the Conners' Rating Scales (CRS), their misuse, and inaccurate reporting by researchers have created a body of literature that is difficult to interpret and misleading to both researchers and clinicians. This review is aimed at clarifying issues regarding the proper use of the CPRS as both a diagnostic instrument and a research tool.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Pais , Agonistas alfa-Adrenérgicos/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/tratamento farmacológico , Transtornos do Comportamento Infantil/etiologia , Clonidina/uso terapêutico , Feminino , Humanos , Masculino , Metilfenidato/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários
8.
Assessment ; 8(3): 351-3, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11575627

RESUMO

This study assesses the test-retest reliability of the revised Advanced Psychodiagnostic Interpretation (API) scoring system for the Bender Gestalt Test (BGT). The API system identifies 207 possible distortions in a BGT protocol. Test-retest reliability for 40 schizophrenic patients tested twice with a mean interval of 6.4 years (SD=3.8 years) was good, ranging from .71 to .80. Further reliability and validity studies are needed to further demonstrate the effectiveness of the system.


Assuntos
Teste de Bender-Gestalt , Esquizofrenia/diagnóstico , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
9.
Clin Psychol Rev ; 21(6): 907-29, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11497212

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed disorder in children today with estimated prevalence rates falling between 3 and 5% of children (American Psychiatric Association, 1994). From inception, research has focused on studying varying facets of this disorder with initial efforts primarily focusing on treatment outcome. However, prominent efforts have been made in recent research efforts to shed light on the etiology of this disorder. Such research has discovered the contribution of genetic inheritance, as well as environmental factors that lead to the development of this disorder. Furthermore, studies using neurological and neuropsychological assessment measures have implicated the involvement of various Parts of the brain. This article critically reviews this body of research in light of its impact on the current specific neuropsychologically based etiological theories, as well as the most beneficial directions for future research.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encefalopatias/complicações , Encefalopatias/fisiopatologia , Criança , Pré-Escolar , Meio Ambiente , Feminino , Lobo Frontal/fisiopatologia , Predisposição Genética para Doença , Humanos , Masculino , Teoria Psicológica
10.
Int J Neurosci ; 111(3-4): 235-40, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11912678

RESUMO

The purpose of the study was to examine the relationship between the Luria-Nebraska Neuropsychological Battery-Third Edition (LNNB-III) and the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III). Participants were 85 adults referred for neuropsychological evaluation. The mean age of participants was 38.73 years (SD = 16.54) and average education was 13.07 years (SD = 2.60). The sample was predominantly female (52.9%), right-handed (86.3%), and Caucasian (68.6%), with the remainder of the population classified as Hispanic (13.7%), African-American (5.9%), or other (11.8%). Diagnoses included 26% psychiatric disorders, 64% neurological disorders, and 10% with no diagnosis. Pearson product correlation yielded a number of significant relationships between the WAIS-III IQ scores and the LNNB-III scales. The highest correlations were with the LNNB Intelligence, Visual-Spatial, Complex Auditory, and Arithmetic scales. Additionally, significant correlations were found between the WAIS-III subtests and a moderate proportion of the LNNB-III subtests. Correlations were also reported for the new WAIS-III scales, Letter-Number Sequencing and Matrix Reasoning. The results suggest that similar abilities are being assessed on both tests. These findings allow clinicians to not only evaluate the consistency of performance across this testing battery, but provide a useful screening instrument for intelligence.


Assuntos
Encefalopatias/complicações , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Bateria Neuropsicológica de Luria-Nebraska , Transtornos Mentais/psicologia , Escalas de Wechsler , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
11.
Int J Neurosci ; 111(3-4): 241-53, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11912679

RESUMO

The present investigation examined neuropsychological functioning in 50 male batterers court-ordered into treatment and 23 nonpatient controls. Subjects were administered a neuropsychological screening battery consisting of the Screening Test for the Luria-Nebraska Neuropsychological Battery, the Stroop Color and Word Test, two memory subtests from the Luria-Nebraska Neuropsychological Battery-III (Figural Memory and Delayed Figural Memory), and two subtests from the Halstead-Reitan Neuropsychological Battery (Trails A & B). Subjects were categorized as having neuropsychological dysfunction if their scores exceeded the statistical cut offs on two or more subtests. Results indicated that 24 (48%) of the male batterers exhibited cognitive dysfunction, as compared to only 1 (4.3%) of the nonpatient controls. Inspection of individual neuropsychological measures indicated poorer performance across all subtests for impaired male batterers as compared to both nonimpaired batterers and normal controls. In contrast, no significant differences on any of these measures emerged between nonimpaired male batterers and normal controls. Implications for the appropriate screening and treatment of male batterers are discussed.


Assuntos
Agressão/psicologia , Transtornos Cognitivos/diagnóstico , Maus-Tratos Conjugais , Adulto , Transtornos Cognitivos/epidemiologia , Humanos , Masculino , Testes Neuropsicológicos , Índice de Gravidade de Doença
12.
Int J Neurosci ; 111(1-2): 109-21, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11913332

RESUMO

In order to better understand whether adolescents with early onset conduct disorder are predisposed to this disorder because of neurological problems, the present study compared the performance of early onset conduct disordered adolescents to adolescents with left hemisphere and right hemisphere brain injuries and normal controls. It was hypothesized that adolescents with early onset conduct disorder would perform similar to adolescents with left hemisphere injury, confirming theories that neurological dysfunction may predispose children to the development of conduct disorder. Fifteen adolescents with conduct disorder were compared on a battery of cognitive tests to 12 left hemisphere brain injured, 11 right hemisphere brain injured, and 15 normal middle school adolescents. F-tests indicated that there were significant differences among the four groups on all measures (p < .01). According to a series of t-tests on each of the nine cognitive measures, there were no differences found between the early onset conduct disordered subjects and the left hemisphere subjects. The early onset conduct disordered group performed worse than the right hemisphere group on 7 of the 9 comparisons, and worse than the normals on 9 of 9 comparisons. The normal group performed better than all three of the other groups. These results demonstrate that the pattern of neuropsychological performance by early onset conduct disordered adolescents was similar to that of left hemisphere injured adolescents and different from that of the right hemisphere injured and normal adolescents. Potential applications of this research include describing new approaches to treatment of this disorder based on their similarity with the left hemisphere brain injured group.


Assuntos
Lesões Encefálicas , Cognição , Transtorno da Conduta , Adolescente , Lesões Encefálicas/psicologia , Transtorno da Conduta/fisiopatologia , Transtorno da Conduta/psicologia , Feminino , Humanos , Inteligência , Masculino , Testes Neuropsicológicos , Fatores de Tempo
14.
Int J Neurosci ; 104(1-4): 113-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11011977

RESUMO

The purpose of this research was to investigate the relationship between recent and long term substance use on adolescents' neuropsychological functioning. Subjects were 77 adolescents who were referred for outpatient treatment for drug and conduct problems. Subjects were administered the Luria-Nebraska Neuropsychological Battery-III, structured interviews to assess substance use, and urine tests. Subjects were divided into neuropsychologically impaired and nonimpaired groups. Results indicated no significant group differences for: self-reports of lifetime use of alcohol, cannabis, and hard drugs; self or collateral reports of recent (past 30 days) use of alcohol, cannabis, and hard drugs; or urinalysis detection of alcohol, cannabis, and hard drugs. Correlations between these dependent measures of substance use and neuropsychological functioning were also nonsignificant (all ps > .05). Although neuropsychological impairment was observed for some subjects in this sample, it was unrelated to their cannabis, hard drug, or alcohol use. These results are consistent with those found in the adult literature, given the relatively short period of time that these youth have used such substances. However, given the severity of their absolute levels of substance usage, they may be at greater risk for developing future neuropsychological problems, related directly to the ingestion of alcohol and illicit drugs, and to their secondary effects (e.g., head traumas, malnutrition).


Assuntos
Bateria Neuropsicológica de Luria-Nebraska , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adolescente , Comportamento do Adolescente/fisiologia , Transtornos Cognitivos/diagnóstico , Terapia Cognitivo-Comportamental/métodos , Feminino , Seguimentos , Humanos , Entrevista Psicológica , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Transtornos Relacionados ao Uso de Substâncias/terapia , Transtornos Relacionados ao Uso de Substâncias/urina
15.
Int J Neurosci ; 103(1-4): 115-26, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10938568

RESUMO

The purpose of this investigation was to evaluate the concurrent validity of the Luria-Nebraska Neuropsychological Battery-Third Edition (LNNB-III) memory scales with the WSM-R (study 1), as well as to investigate performance differences between brain-injured and nonbrain injured subjects on the LNNB-III memory indices, first trial learning, and learning curves of each scale (study 2). Study 1 had 90 subjects (46 males and 44 females). Study 2 had 228 subjects (109 normals and 119 brain-injured). Significant correlations were found between the LNNB-III memory scales and the WSM-R index scores. Findings also revealed poorer overall performance and initial learning of brain-injured subjects across all LNNB-III memory scales. Brain-injured subjects also demonstrated significantly reduced learning curves across repeated trials on two of the three scales. The clinical implications of these findings are discussed.


Assuntos
Lesões Encefálicas/diagnóstico , Testes Neuropsicológicos/normas , Aprendizagem Verbal , Adulto , Feminino , Humanos , Deficiências da Aprendizagem/diagnóstico , Masculino , Transtornos da Memória/diagnóstico , Rememoração Mental , Reprodutibilidade dos Testes , Escalas de Wechsler
16.
Int J Neurosci ; 103(1-4): 131-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10938570

RESUMO

While the Wisconsin Card Sort Test is a popular procedure used to evaluate executive functions, the test may take extended times to administer, especially in impaired clients. This has led to interest in the development of a short form of the test. Axelrod, Paolo, and Abraham (1997) earlier failed in an attempt to develop a short form of the Wisconsin Card Sort Test (WCST). The authors suggested that a regression-based approach might work better than their predictive model. In a sample of 145 consecutive subjects referred for neuropsychological testing, linear and nonlinear regression formulas were generated to predict the full 128 card version of the test from 32, 64, and 96 item versions of the test. Overall, the data obtained strongly suggests that multiple regression equations can reliably predict WCST whole test scores from a 64 or a 96-item version of the test, but not a 32-item version. The results indicate that the 64-item version is a clinically sound substitute for the entire test.


Assuntos
Lesões Encefálicas/diagnóstico , Transtornos Cognitivos/diagnóstico , Testes Neuropsicológicos , Adulto , Feminino , Humanos , Masculino , Análise de Regressão
17.
Int J Neurosci ; 101(1-4): 157-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10765996

RESUMO

The purpose of this research was to examine the clinical utility of the Luria-Nebraska Neuropsychological Battery-Third Edition (LNNB-III) in estimating intellectual functioning as measured by the WAIS-R. Ninety-one subjects were administered the WAIS-R and the LNNB-III. Multiple regression were calculated to examine the ability of the LNNB-III clinical scales to predict FSIQ, VIQ, and PIQ indices. The LNNB-III General Intelligence Scale (GI) predicted FSIQ within 10 points 79% of the time, and within 15 points 97% of the time. Similarly, GI predicted VIQ and PIQ indices with 67% accuracy within 10 points and with 91% and 87% accuracy, respectively, within 15 points. A combination of LNNB clinical scales fared no better than GI alone when predicting the FSIQ index. However, a combination of LNNB-III scales predicted VIQ with 80% accuracy within 10 points and with 94% accuracy within 15 points. In contrast, a combination of LNNB-III clinical scales predicted the PIQ index 76% of the time within 10 points and 90% of the time within 15 points. GI appears to be a good alternative when an estimate of intellectual functioning is desired given its less than 10 minute administration time. When greater specificity regarding VIQ and PIQ estimates are desired, a combination of specific LNNB-III scales appear preferable.


Assuntos
Transtornos Cognitivos/diagnóstico , Bateria Neuropsicológica de Luria-Nebraska , Escalas de Wechsler , Adulto , Feminino , Humanos , Masculino , Valor Preditivo dos Testes
18.
J Psychiatr Res ; 34(2): 129-32, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10758254

RESUMO

Although research has long recognized a relationship between neurological dysfunction and delinquency, the nature of this relationship is unclear. Based on the theory that there may be clusters of delinquents with different types of neurological dysfunction which contribute to the delinquency in different ways, the present research attempted to identify these subtypes using neuropsychological testing. Seventy-seven such adolescents were administered the full Luria-Nebraska Neuropsychological Battery-III (LNNB-III) and a battery of assessments measuring behavioral functioning and substance use. A Hierarchical Cluster Analysis yielded four identifiable neuropsychological clusters: Verbal/Left-Hemispheric Deficits, Subcortical-Frontal Deficits, Mild-Verbal Deficits, and Normals. The distinctiveness of these subtypes was confirmed by univariate analyses. Results further indicated that the number of LNNB scales that were in the abnormal range differed per subtype, with each subtype differing significantly from one another. These neuropsychological subtypes were found to be associated with specific psychological and behavioral problems.


Assuntos
Dano Encefálico Crônico/diagnóstico , Delinquência Juvenil/classificação , Testes Neuropsicológicos , Adolescente , Agressão/fisiologia , Dano Encefálico Crônico/classificação , Dano Encefálico Crônico/psicologia , Comorbidade , Diagnóstico Diferencial , Dominância Cerebral/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Delinquência Juvenil/psicologia , Bateria Neuropsicológica de Luria-Nebraska/estatística & dados numéricos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Determinação da Personalidade/estatística & dados numéricos , Psicometria
19.
Blood ; 95(7): 2364-71, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10733508

RESUMO

To test the hypothesis that cell cycle regulatory gene abnormalities are determinants of clinical outcome in adult acute lymphoblastic leukemia (ALL), we screened lymphoblasts from patients on a Southwest Oncology Group protocol for abnormalities of the genes, retinoblastoma (Rb), p53, p15(INK4B), and p16(INK4A). Aberrant expression occurred in 33 (85%) patients in the following frequencies: Rb, 51%; p16(INK4A), 41%; p53, 26%. Thirteen patients (33%) had abnormalities in 2 or more genes. Outcomes were compared in patients with 0 to 1 abnormality versus patients with multiple abnormalities. The 2 groups did not differ in a large number of clinical and laboratory characteristics. The CR rates for patients with 0 to 1 and multiple abnormalities were similar (69% and 54%, respectively). Patients with 0 to 1 abnormality had a median survival time of 25 months (n = 26; 95% CI, 13-46 months) versus 8 months (n = 13; 95% CI, 4-12 months) for those with multiple abnormalities (P <.01). Stem cells (CD34+lin-) were isolated from adult ALL bone marrows and tested for p16(INK4A) expression by immunocytochemistry. In 3 of 5 patients lymphoblasts and sorted stem cells lacked p16(INK4A) expression. In 2 other patients only 50% of sorted stem cells expressed p16(INK4A). By contrast, p16 expression was present in the CD34+ lin- compartment in 95% (median) of 9 patients whose lymphoblasts expressed p16(INK4A). Therefore, cell cycle regulatory gene abnormalities are frequently present in adult ALL lymphoblasts, and they may be important determinants of disease outcome. The presence of these abnormalities in the stem compartment suggests that they contribute to leukemogenesis. Eradication of the stem cell subset harboring these abnormalities may be important to achieve cure.


Assuntos
Proteínas de Ciclo Celular , Ciclo Celular/genética , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Supressoras de Tumor , Adolescente , Adulto , Idoso , Medula Óssea/química , Proteínas de Transporte/genética , Separação Celular , Inibidor de Quinase Dependente de Ciclina p15 , Inibidor p16 de Quinase Dependente de Ciclina , Feminino , Citometria de Fluxo , Genes do Retinoblastoma/genética , Genes p53/genética , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Indução de Remissão , Taxa de Sobrevida
20.
Angle Orthod ; 69(5): 433-40, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10515141

RESUMO

The purpose of this study was to investigate the effect of surface roughness on the relative corrosion rates of wires of four alloys-stainless steel, nickel titanium, cobalt chromium, and beta titanium. Batches of wire were divided into two groups. Wires in one group were industrially polished to provide a uniform surface finish; wires in the other group were left for comparison "as received." Wire diameter, hardness, and relative corrosion rates were compared within groups before and after polishing. Comparisons were also made across the four groups of alloys. The samples of as-received wires showed variations in surface finish, with beta titanium having the roughest appearance and cobalt chromium the smoothest. Nickel titanium and stainless steel surfaces were similar. Polishing provided a more uniform finish, but significantly reduced the diameter of the wires. Microhardness testing of wire surfaces of each alloy indicated that no significant work-hardening occurred as a result of polishing. The relative corrosion rates (expressed in terms of corrosion current density) in a 0.9% sodium chloride solution were estimated using the electrochemical technique of polarization resistance. Nickel titanium wires exhibited the greatest corrosion current density in the as-received state. Polishing significantly reduced the corrosion rate of nickel titanium, such that comparison between the four alloys in the polished state revealed no significant difference in their relative corrosion rate/corrosion current density.


Assuntos
Ligas Dentárias/química , Polimento Dentário , Fios Ortodônticos , Ligas de Cromo/química , Corrosão , Impedância Elétrica , Eletroquímica , Dureza , Teste de Materiais , Níquel/química , Cloreto de Sódio/química , Aço Inoxidável/química , Propriedades de Superfície , Titânio/química
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