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1.
J Child Adolesc Psychopharmacol ; 30(1): 48-54, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31730370

RESUMO

Objective: To explore blinded observational outcomes in the Treatment of Severe Childhood Aggression (TOSCA) study. Methods: During a 9-week acute trial, children with severe physical aggression and attention-deficit/hyperactivity disorder received parent training + titrated psychostimulant for 3 weeks, and those who failed to show an optimal response during Week 4 through Week 6 received in addition either randomly assigned placebo (Basic treatment) or titrated risperidone (Augmented treatment). Child and parent behaviors were videotaped in a Standardized Observation Analogue Procedure (SOAP) designed to elicit problems and strengths in child and parent interactions. SOAPs were collected at baseline and Week 9 and 52 follow-up. Results: During the acute 9-week trial, augmented treatment was associated with better outcomes than basic treatment for 3 of 13 measures: increased Child Compliance (p = 0.004; significant after correction for multiple tests), greater use of positive Parent Reinforcement (p = 0.03), and more Shared Enjoyment (p = 0.04). At follow-up, when medication was no longer by randomized assignment, parents used more Alpha Commands and displayed fewer Parent Negative Behaviors, and the dyads showed more Shared Enjoyment regardless of original randomization. Thus, there were better parent-child interactions with Augmented treatment, and interactions improved overall at follow-up regardless of original treatment assignment. Conclusions: The SOAP demonstrated sensitivity to behavior changes between short-term treatments for a few (but not most) measures. The acute treatment differences for Child Compliance and Child Negative Behavior are generally consistent with the moderate superiority of Augmented over Basic treatment previously reported for the primary study outcome.


Assuntos
Agressão/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Risperidona/uso terapêutico , Agressão/psicologia , Antipsicóticos/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Criança , Terapia Combinada , Aconselhamento , Feminino , Humanos , Masculino , Resultado do Tratamento
2.
J Child Adolesc Psychopharmacol ; 27(8): 708-714, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28509573

RESUMO

OBJECTIVE: Attention-deficit/hyperactivity disorder (ADHD) symptoms, including inattention and over activity, occur in approximately one-third of children with autism spectrum disorder (ASD). We describe the rate and duration of adverse events in a randomized controlled trial of atomoxetine (ATX) and parent training (PT) for ADHD symptoms and noncompliance in children with ASD. METHODS: We conducted a 10-week, double-blind, 2 × 2 trial of ATX and PT with 128 children (ages 5-14) randomized to ATX alone, ATX+PT, placebo+PT, or placebo alone. For 6 weeks, ATX (or placebo) doses were clinically adjusted to a maximum of 1.8 mg/(kg·day) and maintained for an additional 4 weeks. An average of seven PT sessions were conducted in the two PT arms. Adverse events (AEs) were assessed through parent ratings of common symptoms on a seven-point Likert severity scale and through direct interviews with study medical staff. RESULTS: ATX was associated with decreased appetite and fatigue, but was otherwise well tolerated. Most reported AEs lasted 4 weeks or less. Unlike reports with typically developing (TD) children, there were no concerns with QTc changes or suicidal ideation. CONCLUSIONS: This study extends the findings of previous studies of ATX in ASD by documenting that the type of AEs was similar to that of TD children, with no significant safety concerns.


Assuntos
Inibidores da Captação Adrenérgica/efeitos adversos , Cloridrato de Atomoxetina/efeitos adversos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Espectro Autista/tratamento farmacológico , Adolescente , Inibidores da Captação Adrenérgica/administração & dosagem , Apetite/efeitos dos fármacos , Cloridrato de Atomoxetina/administração & dosagem , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Espectro Autista/psicologia , Criança , Pré-Escolar , Método Duplo-Cego , Fadiga/induzido quimicamente , Feminino , Humanos , Masculino , Pais/educação
3.
J Am Acad Child Adolesc Psychiatry ; 55(10): 868-876.e2, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27663942

RESUMO

OBJECTIVE: The authors previously reported on a 2-by-2 randomized clinical trial of individual and combined treatment with atomoxetine (ATX) and parent training (PT) for attention-deficit/hyperactivity disorder (ADHD) symptoms and behavioral noncompliance in 128 5- to 14-year-old children with autism spectrum disorder. In the present report, they describe a 24-week extension of treatment responders and nonresponders. METHOD: One-hundred seventeen participants from the acute trial (91%) entered the extension; 84 of these were in 2 subgroups: "treatment responders" (n = 43) from all 4 groups in the acute trial, seen monthly for 24 weeks, and "placebo nonresponders" (n = 41), treated with open-label ATX for 10 weeks. Participants originally assigned to PT continued PT during the extension; the remainder served as controls. Primary outcome measurements were the parent-rated Swanson, Nolan and Pelham ADHD scale and the Home Situations Questionnaire. RESULTS: Sixty percent (26 of 43) of treatment responders in the acute trial, including 68% of responders originally assigned to ATX, still met the response criteria at the end of the extension. The response rate of placebo nonresponders treated with 10-week open-label ATX was 37% (15 of 41), similar to the acute trial. Children receiving open-label ATX + PT were significantly more likely to be ADHD responders (53% versus 23%) and noncompliance responders (58% versus 14%) than those receiving open-label ATX alone. CONCLUSION: Most ATX responders maintained their responses during the extension. PT combined with ATX in the open-label trial appeared to improve ADHD and noncompliance outcomes more than ATX alone. Clinical trial registration information-Atomoxetine, Placebo and Parent Management Training in Autism (Strattera); http://clinicaltrials.gov; NCT00844753.


Assuntos
Cloridrato de Atomoxetina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Espectro Autista/terapia , Pais/educação , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Espectro Autista/tratamento farmacológico , Criança , Pré-Escolar , Terapia Combinada , Método Duplo-Cego , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Inquéritos e Questionários , Resultado do Tratamento
4.
J Am Acad Child Adolesc Psychiatry ; 55(6): 469-78, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27238065

RESUMO

OBJECTIVE: The objective of this study was to evaluate 52-week clinical outcomes of children with co-occurring attention-deficit/hyperactivity disorder (ADHD), disruptive behavior disorder, and serious physical aggression who participated in a prospective, longitudinal study that began with a controlled, 9-week clinical trial comparing the relative efficacy of parent training + stimulant medication + placebo (Basic; n = 84) versus parent training + stimulant + risperidone (Augmented; n = 84). METHOD: Almost two-thirds (n = 108; 64%) of families in the 9-week study participated in week 52 follow-ups (Basic, n = 55; Augmented, n = 53) and were representative of the initial study sample. The assessment battery included caregiver and clinician ratings and laboratory tests. RESULTS: Only 43% of participants in the Augmented group and 36% in the Basic group still adhered to their assigned regimen (not significant [NS]); 23% of those in the Augmented group and 11% in the Basic group were taking no medication (NS). Both randomized groups improved baseline to follow-up, but the 3 primary parent-reported behavioral outcomes showed no significant between-group differences. Exploratory analyses indicated that participants in the Augmented group (65%) were more likely (p = .02) to have a Clinical Global Impressions (CGI) severity score of 1 to 3 (i.e., normal to mildly ill) at follow-up than those in the Basic group (42%). Parents rated 45% of children as impaired often or very often from ADHD, noncompliant, or aggressive behavior. The Augmented group had elevated prolactin levels, and the Basic group had decreased weight over time. Findings were generally similar whether groups were defined by randomized assignment or follow-up treatment status. CONCLUSION: Both treatment strategies were associated with clinical improvement at follow-up, and primary behavioral outcomes did not differ significantly. Many children evidenced lingering mental health concerns, suggesting the need for additional research into more effective interventions. Clinical trial registration information-Treatment of Severe Childhood Aggression (the TOSCA Study); http://clinicaltrials.gov/; NCT00796302.


Assuntos
Agressão/fisiologia , Antipsicóticos/farmacologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Risperidona/farmacologia , Agressão/efeitos dos fármacos , Criança , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino
5.
J Am Acad Child Adolesc Psychiatry ; 54(11): 905-15, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26506581

RESUMO

OBJECTIVE: Impairments associated with attention-deficit/hyperactivity disorder (ADHD) and noncompliance are prevalent in children with autism spectrum disorder (ASD). However, ADHD response to stimulants is well below rates in typically developing children, with frequent side effects. Group studies of treatments for noncompliance are rare in ASD. We examined individual and combined-effectiveness of atomoxetine (ATX) and parent training (PT) for ADHD symptoms and noncompliance. METHOD: In a 3-site, 10-week, double-blind, 2 × 2 trial of ATX and PT, 128 children (ages 5-14 years) with ASD and ADHD symptoms were randomized to ATX, ATX+PT, placebo+PT, or placebo. ATX was adjusted to optimal dose (capped at 1.8 mg/kg/day) over 6 weeks and maintained for 4 additional weeks. Nine PT sessions were provided. Primary outcome measures were the parent-rated DSM ADHD symptoms on the Swanson, Nolan and Pelham (SNAP) scale and Home Situations Questionnaire (HSQ). RESULTS: On the SNAP, ATX, ATX+PT and placebo+PT were each superior to placebo (effect sizes 0.57-0.98; p values of .0005, .0004, and .025, respectively). For noncompliance, ATX and ATX+PT were superior to placebo (effect sizes 0.47-0.64; p values .03 and .0028, respectively). ATX was associated with decreased appetite but was otherwise well tolerated. CONCLUSION: Both ATX and PT resulted in significant improvement on ADHD symptoms, whereas ATX (both alone and combined with PT) was associated with significant decreases on measures of noncompliance. ATX appears to have a better side effects profile than psychostimulants in the population with ASD. CLINICAL TRIAL REGISTRATION INFORMATION: Atomoxetine, Placebo and Parent Management Training in Autism; http://clinicaltrials.gov/; NCT00844753.


Assuntos
Inibidores da Captação Adrenérgica/administração & dosagem , Cloridrato de Atomoxetina/administração & dosagem , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Espectro Autista/tratamento farmacológico , Pais/educação , Adolescente , Inibidores da Captação Adrenérgica/efeitos adversos , Cloridrato de Atomoxetina/efeitos adversos , Escala de Avaliação Comportamental , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento , Estados Unidos
6.
J Child Adolesc Psychopharmacol ; 25(3): 213-24, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25885011

RESUMO

OBJECTIVE: In this study, we evaluated parent and child characteristics as predictors and moderators of response in the four-site Treatment of Severe Childhood Aggression (TOSCA) study. METHODS: A total of 168 children with severe aggression, disruptive behavior disorder, and attention-deficit/hyperactivity disorder (ADHD) were enrolled in a 9-week trial of basic treatment (n=84, stimulant+parent training+placebo) versus augmented treatment (n=84, stimulant+parent training+risperidone). In the initial report, augmented treatment surpassed basic treatment in reducing the primary outcome of disruptive behavior (D-Total) scores. In the current study, we evaluated parent (income, education, family functioning, employment) and child variables (intelligence quotient [IQ], aggression type, comorbid symptomatology) as predictors or moderators, using linear mixed models and the MacArthur guidelines. RESULTS: Higher scores on ADHD symptom severity and callous/unemotional traits predicted better outcome on D-Total regardless of treatment assignment. Two moderators of D-Total were found: Higher anger/irritability symptoms and lower mania scores were associated with faster response, although not better overall effect at endpoint, in the augmented but not the basic group. Several variables moderated response on secondary outcomes (ADHD severity and prosocial behavior), and were characterized by faster response, although not better outcome, in the augmented but not in the basic group. Maternal education moderated outcome on the measure of positive social behavior; children of mothers with less education benefited more from augmented treatment relative to basic than those with more education. CONCLUSION: Although these findings require validation, they tentatively suggest that augmented treatment works equally well across the entire sample. Nevertheless, certain child characteristics may be useful indicators for the speed of response to augmented treatment.


Assuntos
Agressão/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Risperidona/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/complicações , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pais/educação , Risperidona/administração & dosagem , Índice de Gravidade de Doença , Comportamento Social , Resultado do Tratamento
7.
J Child Adolesc Psychopharmacol ; 25(3): 225-33, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25885012

RESUMO

OBJECTIVE: The purpose of this study was to examine the satisfaction of families who participated in the Treatment of Severe Childhood Aggression (TOSCA) study. METHODS: TOSCA was a randomized clinical trial of psychostimulant plus parent training plus placebo (basic treatment) versus psychostimulant plus parent training plus risperidone (augmented treatment) for children with severe physical aggression, disruptive behavior disorder, and attention-deficit/hyperactivity disorder. Parents completed a standardized Parent Satisfaction Questionnaire (PSQ). RESULTS: Of the 168 families randomized, 150 (89.3%) provided consumer satisfaction data. When they were asked if they would join the study again if they had the option to repeat, 136 (91%) said "yes," 11 (7%) said "maybe," and one (<1%) said "no." When asked if they would recommend the study to other parents with children having similar problems, 147 (98%) said "yes" and 3 (2%) said "maybe." Between 71% (rating one aspect of the Parent Training) and 96% (regarding the diagnostic interview) endorsed study procedures using the most positive response option. Asked if there were certain aspects of the study that they especially liked, 64 (43%) spontaneously reported parent training. Treatment assignment (basic vs. augmented) and responder status were not associated with reported satisfaction. However, responder status was strongly associated with parent confidence in managing present (p<0.001) and future (p<0.005) problem behaviors. CONCLUSIONS: These findings indicate high levels of satisfaction with TOSCA study involvement and, taken together with previous pediatric psychopharmacology social validity studies, suggest high levels of support for the research experience. These findings may inform research bioethics and may have implications for deliberations of institutional review boards. TRIAL REGISTRY: Treatment of Severe Childhood Aggression (The TOSCA Study), NCT00796302, clinicaltrials.gov .


Assuntos
Agressão/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Risperidona/uso terapêutico , Antipsicóticos/administração & dosagem , Antipsicóticos/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/complicações , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pais/educação , Pais/psicologia , Satisfação do Paciente , Risperidona/administração & dosagem , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento
8.
J Am Acad Child Adolesc Psychiatry ; 53(9): 948-959.e1, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25151418

RESUMO

OBJECTIVE: In this study, we aimed to expand on our prior research into the relative efficacy of combining parent training, stimulant medication, and placebo (Basic therapy) versus parent training, stimulant, and risperidone (Augmented therapy) by examining treatment effects for attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD) symptoms and peer aggression, symptom-induced impairment, and informant discrepancy. METHOD: Children (6-12 years of age; N = 168) with severe physical aggression, ADHD, and co-occurring ODD/CD received an open trial of parent training and stimulant medication for 3 weeks. Participants failing to show optimal clinical response were randomly assigned to Basic or Augmented therapy for an additional 6 weeks. RESULTS: Compared with Basic therapy, children receiving Augmented therapy experienced greater reduction in parent-rated ODD severity (p = .002, Cohen's d = 0.27) and peer aggression (p = .02, Cohen's d = 0.32) but not ADHD or CD symptoms. Fewer children receiving Augmented (16%) than Basic (40%) therapy were rated by their parents as impaired by ODD symptoms at week 9/endpoint (p = .008). Teacher ratings indicated greater reduction in ADHD severity (p = .02, Cohen's d = 0.61) with Augmented therapy, but not for ODD or CD symptoms or peer aggression. Although both interventions were associated with marked symptom reduction, a relatively large percentage of children were rated as impaired for at least 1 targeted disorder at week 9/endpoint by parents (Basic 47%; Augmented 27%) and teachers (Basic 48%; Augmented 38%). CONCLUSION: Augmented therapy was superior to Basic therapy in reducing severity of ADHD and ODD symptoms, peer aggression, and symptom-induced impairment, but clinical improvement was generally context specific, and effect sizes ranged from small to moderate. Clinical trial registration information-Treatment of Severe Childhood Aggression (The TOSCA Study); http://clinicaltrials.gov/; NCT00796302.


Assuntos
Agressão/efeitos dos fármacos , Antipsicóticos/farmacologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Estimulantes do Sistema Nervoso Central/farmacologia , Transtorno da Conduta/terapia , Educação em Saúde/métodos , Pais/educação , Risperidona/farmacologia , Antipsicóticos/administração & dosagem , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Terapia Combinada , Transtorno da Conduta/tratamento farmacológico , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Grupo Associado , Risperidona/administração & dosagem , Resultado do Tratamento
9.
J Am Acad Child Adolesc Psychiatry ; 53(1): 47-60.e1, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24342385

RESUMO

OBJECTIVE: Although combination pharmacotherapy is common in child and adolescent psychiatry, there has been little research evaluating it. The value of adding risperidone to concurrent psychostimulant and parent training (PT) in behavior management for children with severe aggression was tested. METHOD: One hundred sixty-eight children 6 to 12 years old (mean age 8.89 ± 2.01 years) with severe physical aggression were randomized to a 9-week trial of PT, stimulant (STIM), and placebo (Basic treatment; n = 84) or PT, STIM, and risperidone (Augmented treatment; n = 84). All had diagnoses of attention-deficit/hyperactivity disorder and oppositional-defiant disorder (n = 124) or conduct disorder (n = 44). Children received psychostimulant (usually Osmotic Release Oral System methylphenidate) for 3 weeks, titrated for optimal effect, while parents received PT. If there was room for improvement at the end of week 3, placebo or risperidone was added. Assessments included parent ratings on the Nisonger Child Behavior Rating Form (Disruptive-Total subscale was the primary outcome) and Antisocial Behavior Scale; blinded clinicians rated change on the Clinical Global Impressions scale. RESULTS: Compared with Basic treatment (PT + STIM [44.8 ± 14.6 mg/day] + placebo [1.88 mg/day ± 0.72]), Augmented treatment (PT + STIM [46.1 ± 16.8 mg/day] + risperidone [1.65 mg/day ± 0.75]) showed statistically significant improvement on the Nisonger Child Behavior Rating Form Disruptive-Total subscale (treatment-by-time interaction, p = .0016), the Nisonger Child Behavior Rating Form Social Competence subscale (p = .0049), and Antisocial Behavior Scale Reactive Aggression subscale (p = .01). Clinical Global Impressions scores were substantially improved for the 2 groups but did not discriminate between treatments (Clinical Global Impressions-Improvement score ≤2, 70% for Basic treatment versus 79% for Augmented treatment). Prolactin elevations and gastrointestinal upset occurred more with Augmented treatment; other adverse events differed modestly from Basic treatment; weight gain in the Augmented treatment group was minor. CONCLUSIONS: Risperidone provided moderate but variable improvement in aggressive and other seriously disruptive child behaviors when added to PT and optimized stimulant treatment. Clinical trial registration information-Treatment of Severe Childhood Aggression (The TOSCA Study), URL: http://clinicaltrials.gov, unique identifier: NCT00796302.


Assuntos
Agressão/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Estimulantes do Sistema Nervoso Central/farmacologia , Pais/educação , Risperidona/farmacologia , Agressão/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Terapia Combinada , Sinergismo Farmacológico , Humanos , Masculino , Risperidona/administração & dosagem , Resultado do Tratamento
10.
Opt Express ; 18(12): 12411-4, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20588367

RESUMO

We report evidence of beam cleanup during stimulated Raman scattering in silicon. An amplified near-diffraction-limited Stokes beam is obtained from a severely aberrated pump beam.

11.
Opt Express ; 18(5): 4972-9, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20389508

RESUMO

For the first time to the best of our knowledge a glass-clad optical fiber comprising a crystalline binary III-V semiconductor core has been fabricated. More specifically, a phosphate glass-clad fiber containing an indium antimonide (InSb) core was drawn using a molten core approach. The core was found to be highly crystalline with some oxygen and phosphorus diffusing in from the cladding glass. While optical transmission measurements were unable to be made, most likely due to free carrier absorption associated with the conductivity of the core, this work constitutes a proof-of-concept that optical fibers comprising semiconductor cores of higher crystallographic complexity than previously realized can be drawn using conventional fiber fabrication techniques. Such binary semiconductors may open the door to future fiber-based nonlinear devices.

12.
Opt Lett ; 33(4): 354-6, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18278108

RESUMO

A diffractive optical element (DOE) is used as a beam combiner for an actively phase-locked array of fiber lasers. Use of a DOE eliminates the far-field sidelobes and the accompanying loss of beam quality typically observed in tiled coherent laser arrays. Using this technique, we demonstrated coherent combination of five fiber lasers with 91% efficiency and M2=1.04. Combination efficiency and phase locking is robust even with large amplitude and phase fluctuations on the input laser array elements. Calculations and power handling measurements suggest that this approach can scale to both high channel counts and high powers.

13.
Am J Hum Genet ; 80(6): 1037-54, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17503323

RESUMO

Interindividual gene copy-number variation (CNV) of complement component C4 and its associated polymorphisms in gene size (long and short) and protein isotypes (C4A and C4B) probably lead to different susceptibilities to autoimmune disease. We investigated the C4 gene CNV in 1,241 European Americans, including patients with systemic lupus erythematosus (SLE), their first-degree relatives, and unrelated healthy subjects, by definitive genotyping and phenotyping techniques. The gene copy number (GCN) varied from 2 to 6 for total C4, from 0 to 5 for C4A, and from 0 to 4 for C4B. Four copies of total C4, two copies of C4A, and two copies of C4B were the most common GCN counts, but each constituted only between one-half and three-quarters of the study populations. Long C4 genes were strongly correlated with C4A (R=0.695; P<.0001). Short C4 genes were correlated with C4B (R=0.437; P<.0001). In comparison with healthy subjects, patients with SLE clearly had the GCN of total C4 and C4A shifting to the lower side. The risk of SLE disease susceptibility significantly increased among subjects with only two copies of total C4 (patients 9.3%; unrelated controls 1.5%; odds ratio [OR] = 6.514; P=.00002) but decreased in those with > or =5 copies of C4 (patients 5.79%; controls 12%; OR=0.466; P=.016). Both zero copies (OR=5.267; P=.001) and one copy (OR=1.613; P=.022) of C4A were risk factors for SLE, whereas > or =3 copies of C4A appeared to be protective (OR=0.574; P=.012). Family-based association tests suggested that a specific haplotype with a single short C4B in tight linkage disequilibrium with the -308A allele of TNFA was more likely to be transmitted to patients with SLE. This work demonstrates how gene CNV and its related polymorphisms are associated with the susceptibility to a human complex disease.


Assuntos
Complemento C4/genética , Dosagem de Genes , Variação Genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , População Branca/genética , Adulto , Alelos , Estudos de Casos e Controles , Estudos de Coortes , Suscetibilidade a Doenças , Feminino , Frequência do Gene , Genética Populacional , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco
14.
Opt Express ; 15(6): 3396-408, 2007 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19532581

RESUMO

We propose a new type of waveguide optical amplifier. The device consists of collinearly propagating pump and amplified Stokes beams with periodic imaging of the Stokes beam due to the Talbot effect. The application of this device as an Image preamplifier for Mid Wave Infrared (MWIR) remote sensing is discussed and its performance is described. Silicon is the preferred material for this application in MWIR due to its excellent transmission properties, high thermal conductivity, high damage threshold and the mature fabrication technology. In these devices, the Raman amplification process also includes four-wave-mixing between various spatial modes of pump and Stokes signals. This phenomenon is unique to nonlinear interactions in multimode waveguides and places a limit on the maximum achievable gain, beyond which the image begins to distort. Another source of image distortion is the preferential amplification of Stokes modes that have the highest overlap with the pump. These effects introduce a tradeoff between the gain and image quality. We show that a possible solution to this trade-off is to restrict the pump into a single higher order waveguide mode.

15.
Opt Express ; 15(22): 14355-62, 2007 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-19550712

RESUMO

We demonstrate, for the first time, a mid infrared silicon Raman amplifier. Amplification of 12 dB is reported for a signal at 3.39 micron wavelength. The active medium was a 2.5 cm long silicon sample that was pumped with 5ns pulses at 2.88 micron. Such a technology can potentially extend silicon photonics' application beyond data communication in the near IR and into the mid-IR world of remote sensing, biochemical detection and laser medicine. Challenges faced in the mid-IR regime such as a higher free carrier scattering rate longer lifetime in mid-IR waveguides are also discussed.

16.
Methods Enzymol ; 392: 405-19, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15644195

RESUMO

We describe two complementary strategies for preparing DNA-directed RNA interference (ddRNAi) constructs designed to express hpRNA. The first, oligonucleotide assembly (OA), uses a very simple annealing protocol to combine up to 20 short nucleotides. These are then cloned into appropriately designed restriction sites in expression vectors. OA can be used to prepare simple hairpin (hp)-expressing constructs, but we prefer to use the approach to generate longer constructs. The second strategy, long-range cloning (LRC), uses a novel adaptation of long-range PCR protocols. For LRC, entire vectors are amplified with primers that serve to introduce short sequences into plasmids at defined anchor sites during PCR. The LCR strategy has proven highly reliable in our hands for generating simple ddRNAi constructs. Moreover, LCR is likely to prove useful in many situations in which conventional cloning strategies might prove problematic. In combination, OA and LRC can greatly simplify the design and generation of many expression constructs, including constructs for ddRNAi.


Assuntos
DNA/química , Interferência de RNA , Sequência de Bases , Clonagem Molecular , Eletroforese em Gel de Ágar
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