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1.
Artigo em Inglês | MEDLINE | ID: mdl-33937907

RESUMO

Objective: Pregnancy requires a complex physiological adaptation of the maternal cardiovascular system, which is disrupted in women with pregnancies complicated by preeclampsia, putting them at higher risk of future cardiovascular events. The measurement of body movements in response to cardiac ejection via ballistocardiogram (BCG) can be used to assess cardiovascular hemodynamics noninvasively in women with preeclampsia. Methods: Using a previously validated, modified weighing scale for assessment of cardiovascular hemodynamics through measurement of BCG and electrocardiogram (ECG) signals, we collected serial measurements throughout pregnancy and postpartum and analyzed data in 30 women with preeclampsia and 23 normotensive controls. Using BCG and ECG signals, we extracted measures of cardiac output, J-wave amplitude × heart rate (J-amp × HR). Mixed-effect models with repeated measures were used to compare J-amp × HRs between groups at different time points in pregnancy and postpartum. Results: In normotensive controls, the J-amp × HR was significantly lower early postpartum (E-PP) compared with the second trimester (T2; p = 0.016) and third trimester (T3; p = 0.001). Women with preeclampsia had a significantly lower J-amp × HR compared with normotensive controls during the first trimester (T1; p = 0.026). In the preeclampsia group, there was a trend toward an increase in J-amp × HR from T1 to T2 and then a drop in J-amp × HR at T3 and further drop at E-PP. Conclusions: We observe cardiac hemodynamic changes consistent with those reported using well-validated tools. In pregnancies complicated by preeclampsia, the maximal force of contraction is lower, suggesting lower cardiac output and a trend in hemodynamics consistent with the hyperdynamic disease model of preeclampsia.

2.
IEEE J Biomed Health Inform ; 25(3): 634-646, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32750964

RESUMO

OBJECTIVE: To estimate instantaneous oxygen uptake VO2 with a small, low-cost wearable sensor during exercise and daily activities in order to enable monitoring of energy expenditure (EE) in uncontrolled settings. We aim to do so using a combination of seismocardiogram (SCG), electrocardiogram (ECG) and atmospheric pressure (AP) signals obtained from a minimally obtrusive wearable device. METHODS: In this study, subjects performed a treadmill protocol in a controlled environment and an outside walking protocol in an uncontrolled environment. During testing, the COSMED K5 metabolic system collected gold standard breath-by-breath (BxB) data and a custom-built wearable patch placed on the mid-sternum collected SCG, ECG and AP signals. We extracted features from these signals to estimate the BxB VO2 data obtained from the COSMED system. RESULTS: In estimating instantaneous VO2, we achieved our best results on the treadmill protocol using a combination of SCG (frequency) and AP features (RMSE of 3.68 ± 0.98 ml/kg/min and R2 of 0.77). For the outside protocol, we achieved our best results using a combination of SCG (frequency), ECG and AP features (RMSE of 4.3 ± 1.47 ml/kg/min and R2 of 0.64). In estimating VO2 consumed over one minute intervals during the protocols, our median percentage error was 15.8[Formula: see text] for the treadmill protocol and 20.5[Formula: see text] for the outside protocol. CONCLUSION: SCG, ECG and AP signals from a small wearable patch can enable accurate estimation of instantaneous VO2 in both controlled and uncontrolled settings. SCG signals capturing variation in cardio-mechanical processes, AP signals, and state of the art machine learning models contribute significantly to the accurate estimation of instantaneous VO2. SIGNIFICANCE: Accurate estimation of VO2 with a low cost, minimally obtrusive wearable patch can enable the monitoring of VO2 and EE in everyday settings and make the many applications of these measurements more accessible to the general public.


Assuntos
Exercício Físico , Dispositivos Eletrônicos Vestíveis , Eletrocardiografia , Humanos , Oxigênio , Consumo de Oxigênio , Caminhada
3.
IEEE Trans Biomed Eng ; 67(5): 1303-1313, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31425011

RESUMO

OBJECTIVE: To improve home monitoring of heart failure patients so as to reduce emergency room visits and hospital readmissions. We aim to do this by analyzing the ballistocardiogram (BCG) to evaluate the clinical state of the patient. METHODS: 1) High quality BCG signals were collected at home from HF patients after discharge. 2) The BCG recordings were preprocessed to exclude outliers and artifacts. 3) Parameters of the BCG that contain information about the cardiovascular system were extracted. These features were used for the task of classification of the BCG recording based on the status of HF. RESULTS: The best AUC score for the task of classification obtained was 0.78 using slight variant of the leave one subject out validation method. CONCLUSION: This work demonstrates that high quality BCG signals can be collected in a home environment and used to detect the clinical state of HF patients. SIGNIFICANCE: In future work, a clinician/caregiver can be introduced into the system so that appropriate interventions can be performed based on the clinical state monitored at home.


Assuntos
Balistocardiografia , Insuficiência Cardíaca , Artefatos , Insuficiência Cardíaca/diagnóstico , Humanos , Monitorização Fisiológica
4.
Am J Med Genet A ; 179(1): 85-93, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30569586

RESUMO

Measures of adaptive behavior are important in the assessment and treatment of individuals with intellectual disabilities (ID). The purpose of the current study was to evaluate the stability of an established and a novel measure of adaptive behavior over time, and their suitability as outcome measures in clinical trials targeting individuals with Down syndrome (DS). This 6-month, longitudinal, noninterventional, multinational study included adolescents (12-17 years) and adults (18-30 years) with DS. Participants were from seven countries (11 different sites) with English, Spanish and French as their native language. The Vineland Adaptive Behavior Scales-II (VABS-II) and a newly developed Clinician Global Impression (CGI) scale were administered at baseline, 1 and 6 months. Adults had lower composite standard scores on all domains of the VABS-II compared with adolescents. The communication domain was a weakness relative to the socialization and daily living skills domains on the VABS-II and the CGI-Severity scale. These findings were stable over 6 months, as exhibited by high intraclass correlations (>0.75). These results provide valuable baseline data for use in trial design and endpoint selection for studies including individuals with DS. ClinicalTrials.gov identifier: NCT01580384.


Assuntos
Adaptação Psicológica , Síndrome de Down/genética , Deficiência Intelectual/fisiopatologia , Atividades Cotidianas/psicologia , Adolescente , Adulto , Criança , Síndrome de Down/fisiopatologia , Feminino , Humanos , Deficiência Intelectual/psicologia , Estudos Longitudinais , Masculino , Socialização , Adulto Jovem
5.
Am J Med Genet A ; 170(6): 1545-55, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27061338

RESUMO

Individuals with Down syndrome (DS) have decreased cholinergic function and an uneven profile of cognitive abilities, with more pronounced deficits in learning, memory, and expressive language. Cholinesterase inhibitors may improve cognitive function in adults and adolescents with DS, but studies in children with DS have been limited. This study aimed to: (i) investigate the safety and efficacy of rivastigmine treatment; (ii) build upon our open-label studies in children with DS in a double-blind, placebo-controlled clinical trial; and (iii) investigate specific cognitive domains that may respond to rivastigmine treatment. We conducted a 20-week double-blind, placebo-controlled trial to investigate the safety and efficacy of rivastigmine in 22 children and adolescents with DS aged 10-17 years. Safety measures included reports of adverse events, laboratory parameters, and electrocardiograms. Efficacy measures included parental assessments of adaptive behavior and executive function, and direct measures of language and memory. No group differences were found on safety measures and 22 of 24 participants that passed study screening completed the study. The results did not demonstrate evidence for significant improvement in aspects of cognition, language, or overall function in the children receiving rivastigmine. Our results suggest that rivastigmine is safe and well-tolerated for children and adolescents with DS, but may not be effective for improving performance on the selected measures in this study. However, larger samples and/or alternate measures could possibly reveal improvements in cognitive function with rivastigmine treatment. Further research is needed to define a battery of cognitive measures that is sensitive to treatment effects in DS. © 2016 Wiley Periodicals, Inc.


Assuntos
Síndrome de Down/tratamento farmacológico , Rivastigmina/uso terapêutico , Adaptação Psicológica/efeitos dos fármacos , Adolescente , Criança , Cognição/efeitos dos fármacos , Síndrome de Down/diagnóstico , Eletrocardiografia , Feminino , Humanos , Masculino , Rivastigmina/administração & dosagem , Rivastigmina/efeitos adversos , Resultado do Tratamento
6.
ASAIO J ; 62(2): 169-75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26692401

RESUMO

Silicon nanopore membranes (SNMs) with compact geometry and uniform pore size distribution have demonstrated a remarkable capacity for hemofiltration. These advantages could potentially be used for hemodialysis. Here, we present an initial evaluation of the SNM's mechanical robustness, diffusive clearance, and hemocompatibility in a parallel plate configuration. Mechanical robustness of the SNM was demonstrated by exposing membranes to high flows (200 ml/min) and pressures (1,448 mm Hg). Diffusive clearance was performed in an albumin solution and whole blood with blood and dialysate flow rates of 25 ml/min. Hemocompatibility was evaluated using scanning electron microscopy and immunohistochemistry after 4 hours in an extracorporeal porcine model. The pressure drop across the flow cell was 4.6 mm Hg at 200 ml/min. Mechanical testing showed that SNM could withstand up to 775.7 mm Hg without fracture. Urea clearance did not show an appreciable decline in blood versus albumin solution. Extracorporeal studies showed blood was successfully driven via the arterial-venous pressure differential without thrombus formation. Bare silicon showed increased cell adhesion with a 4.1-fold increase and 1.8-fold increase over polyethylene glycol (PEG)-coated surfaces for tissue plasminogen factor (t-PA) and platelet adhesion (CD41), respectively. These initial results warrant further design and development of a fully scaled SNM-based parallel plate dialyzer for renal replacement therapy.


Assuntos
Membranas Artificiais , Diálise Renal/instrumentação , Diálise Renal/métodos , Animais , Desenho de Equipamento , Nanoporos , Silício , Suínos
7.
Front Behav Neurosci ; 9: 300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26635554

RESUMO

Down syndrome (DS) is the most commonly identifiable genetic form of intellectual disability. Individuals with DS have considerable deficits in intellectual functioning (i.e., low intellectual quotient, delayed learning and/or impaired language development) and adaptive behavior. Previous pharmacological studies in this population have been limited by a lack of appropriate endpoints that accurately measured change in cognitive and functional abilities. Therefore, the current longitudinal observational study assessed the suitability and reliability of existing cognitive scales to determine which tools would be the most effective in future interventional clinical studies. Subtests of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Cambridge Neuropsychological Test Automated Battery (CANTAB), and Clinical Evaluation of Language Fundamentals-Preschool-2 (CELF-P-2), and the Observer Memory Questionnaire-Parent Form (OMQ-PF), Behavior Rating Inventory of Executive Function®-Preschool Version (BRIEF-P) and Leiter International Performance Scale-Revised were assessed. The results reported here have contributed to the optimization of trial design and endpoint selection for the Phase 2 study of a new selective negative allosteric modulator of the GABAA receptor α5-subtype (Basmisanil), and can be applied to other studies in the DS population.

9.
Am J Med Genet C Semin Med Genet ; 160C(1): 22-9, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22253038

RESUMO

This report documents the long-term cognitive and adaptive outcome of children with infantile Pompe disease. Specifically, we describe the cognitive and adaptive functioning of seven children with classic infantile Pompe disease and two children with atypical infantile Pompe disease who have received enzyme replacement therapy (Myozyme®) for an average of 6 years, 8 months and 4 years, 1. 5 months, respectively. Multiple assessments of cognitive functioning were completed over time by means of individualized intelligence (IQ) testing. Adaptive functioning was measured by means of the Vineland Adaptive Behavior Scales-Second Edition (VABS-II). Consistent with our earlier findings regarding infants treated with ERT, children with classic infantile Pompe disease (ages 4 years, 11 months to 8 years, 11 months) were functioning at the lower end of the average range in comparison to their typical peers on their most recent IQ test. There was no evidence of a decline in their cognitive abilities over time. In contrast, the two children with atypical infantile Pompe disease (ages 5 years, 4 months and 5 years, 11 months) obtained above average IQ scores and demonstrated significant gains in IQ over time. For all children where adaptive functioning was assessed, their overall level of adaptive functioning on the VABS-II was lower than their Full Scale IQ scores on cognitive testing. Motor function appears to be an important factor impacting on reduced adaptive behavior. The implication of these findings on our understanding of a possible relationship between CNS status in children with Pompe and their adaptive and cognitive function is discussed.


Assuntos
Cognição , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Doença de Depósito de Glicogênio Tipo II/terapia , Testes de Inteligência , Adaptação Psicológica , Criança , Pré-Escolar , Feminino , Seguimentos , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Humanos , Lactente , Masculino , Resultado do Tratamento
10.
Mol Genet Metab ; 105(3): 428-32, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22217428

RESUMO

This report describes the cognitive development of 17 children with infantile Pompe disease who participated in a 52-week clinical trial of enzyme replacement therapy (ERT) via biweekly infusion of Myozyme® (alglucosidase alfa). Subjects were six months of age or younger (adjusted for gestational age) upon initiation of ERT. The Mental Scale of the Bayley Scales of Infant Development-Second Edition (BSID-II) was administered to obtain a Mental Development Index (MDI) at baseline and weeks 12, 26, 38, and 52 of ERT to assess cognitive development in this treated cohort. Data regarding motor development were also obtained at the same visits and these were used to determine correlations between cognitive and motor development. Over the course of the study, two subgroups of subjects emerged: high responders who were sitting independently and/or ambulating by week 52 (n=13) and limited responders who showed minimal motor gains throughout the first year of ERT (n=4). In the high responder group, MDI scores on the BSID-II remained stable throughout the study and were within normal limits. Positive correlations between cognitive and motor development were also present. These data suggest that the cognitive function of infants up to 18 months of age with Pompe disease is unaffected by the possible presence of glycogen in the central nervous system. Continued investigation of the cognitive development of older survivors is warranted.


Assuntos
Cognição , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/uso terapêutico , Estudos de Coortes , Feminino , Glicogênio/análise , Doença de Depósito de Glicogênio Tipo II/psicologia , Humanos , Lactente , Recém-Nascido , Masculino , Destreza Motora , alfa-Glucosidases/deficiência , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
11.
J Child Adolesc Psychopharmacol ; 20(6): 517-20, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21186971

RESUMO

Following the completion of a 20-week, open-label study of the safety and efficacy of liquid rivastigmine for adolescents with Down syndrome, 5 of the 10 adolescents in the clinical trial continued long-term rivastigmine therapy and 5 did not. After an average period of 38 months, all 10 subjects returned for a follow-up assessment to determine the safety and efficacy of long-term rivastigmine use. Rivastigmine was well tolerated and overall health appeared to be unaffected by long-term rivastigmine use. Performance change on cognitive and language measures administered at the termination of the open-label clinical trial was compared between the two groups. No between-group difference in median performance change across the long-term period was found, suggesting that the long-term use of rivastigmine does not improve cognitive and language performance. However, two subjects demonstrated remarkable improvement in adaptive function over the long-term period. Both subjects had received long-term rivastigmine therapy. The discussion addresses the challenge of assessing cognitive change in clinical trials using adolescents with Down syndrome as subjects and the use of group versus individual data to evaluate the relevance of medication effects.


Assuntos
Cognição/efeitos dos fármacos , Síndrome de Down/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fenilcarbamatos/uso terapêutico , Adolescente , Seguimentos , Humanos , Transtornos da Linguagem/tratamento farmacológico , Transtornos da Linguagem/etiologia , Testes de Linguagem , Masculino , Fármacos Neuroprotetores/efeitos adversos , Fenilcarbamatos/efeitos adversos , Rivastigmina , Fatores de Tempo
12.
Am J Med Genet A ; 152A(12): 3028-35, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21108390

RESUMO

The objective of this 10-week, randomized, double-blind, placebo-controlled multicenter study was to assess the efficacy and safety of donepezil for the treatment of cognitive dysfunction exhibited by children with Down syndrome (DS). Intervention comprised donepezil (2.5-10 mg/day) in children (aged 10-17 years) with DS of mild-to-moderate severity. The primary measures were the Vineland-II Adaptive Behavior Scales (VABS-II) Parent/Caregiver Rating Form (PCRF) the sum of nine subdomain standardized scores and standard safety measures. Secondary measures included the VABS-II/PCRF scores on the following domains and their respective individual subdomains: Communication (receptive, expressive, and written); Daily Living Skills (personal, domestic, and community); Socialization (interpersonal relationships, play and leisure time, and coping skills), and scores on the Test of Verbal Expression and Reasoning, a subject-performance-based measure of expressive language. At baseline, 129 participants were assigned treatment with donepezil or placebo. During the double-blind phase, VABS II/PCRF sum of the nine subdomain standardized scores, called v-scores, improved significantly from baseline in both groups (P < 0.0001), with no significant between-group differences. This trial failed to demonstrate any benefit for donepezil versus placebo in children and adolescents with DS, although donepezil appeared to be well tolerated.


Assuntos
Inibidores da Colinesterase/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Síndrome de Down/tratamento farmacológico , Indanos/uso terapêutico , Piperidinas/uso terapêutico , Adolescente , Comportamento/efeitos dos fármacos , Cuidadores/psicologia , Criança , Inibidores da Colinesterase/efeitos adversos , Inibidores da Colinesterase/farmacologia , Transtornos Cognitivos/fisiopatologia , Diarreia/induzido quimicamente , Donepezila , Relação Dose-Resposta a Droga , Método Duplo-Cego , Síndrome de Down/fisiopatologia , Tolerância a Medicamentos , Feminino , Humanos , Indanos/efeitos adversos , Indanos/farmacologia , Aprendizagem/efeitos dos fármacos , Masculino , Testes Neuropsicológicos , Piperidinas/efeitos adversos , Piperidinas/farmacologia , Índice de Gravidade de Doença , Vômito/induzido quimicamente
13.
Dysphagia ; 25(4): 277-83, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19763689

RESUMO

Pompe disease is a rare genetic progressive neuromuscular disorder. The most severe form, infantile Pompe disease, has historically resulted in early mortality, most commonly due to cardiorespiratory failure. Treatment with enzyme replacement therapy (ERT) using alglucosidase alfa (Myozyme(®)) has extended the lifespan of individuals with this disease. With the introduction of ERT and the resultant improved survival, dysphagia is being encountered clinically with increasing regularity though systematic data remain unavailable. We retrospectively studied the oropharyngeal swallowing of 13 infants and children with Pompe disease using videofluoroscopy before initiation of ERT, allowing for baseline swallow function to be established in an untreated cohort. Dysphagia was present in all 13 subjects, even in a participant only 15 days old. Oral stage signs were present in 77%, most frequently a weak suck in 69%. Pharyngeal stage signs were present in 100%, including a pharyngeal swallow delay in 92% and pharyngeal residue in 77%. Airway invasion was present in 76.9% of subjects, including penetration in five (38.46%) and silent aspiration in an additional five (38.46%). No relationship in the relative involvement of swallowing, gross motor function, and cardiac disease appeared to be present.


Assuntos
Transtornos de Deglutição/etiologia , Terapia de Reposição de Enzimas/métodos , Doença de Depósito de Glicogênio Tipo II/complicações , Doença de Depósito de Glicogênio Tipo I/complicações , alfa-Glucosidases/uso terapêutico , Transtornos de Deglutição/tratamento farmacológico , Transtornos de Deglutição/patologia , Progressão da Doença , Feminino , Fluoroscopia , Doença de Depósito de Glicogênio Tipo I/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo I/patologia , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/patologia , Indicadores Básicos de Saúde , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Estatística como Assunto , Fatores de Tempo , Gravação em Vídeo , alfa-Glucosidases/metabolismo
14.
Mol Genet Metab ; 99(1): 26-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19775921

RESUMO

Deficiency of acid alpha glucosidase (GAA) causes Pompe disease, which is usually fatal if onset occurs in infancy. Patients synthesize a non-functional form of GAA or are unable to form native enzyme. Enzyme replacement therapy with recombinant human GAA (rhGAA) prolongs survival in infantile Pompe patients but may be less effective in cross-reactive immunologic material (CRIM)-negative patients. We retrospectively analyzed the influence of CRIM status on outcome in 21 CRIM-positive and 11 CRIM-negative infantile Pompe patients receiving rhGAA. Patients were from the clinical setting and from clinical trials of rhGAA, were 6 months of age, were not invasively ventilated, and were treated with IV rhGAA at a cumulative or total dose of 20 or 40 mg/kg/2 weeks. Outcome measures included survival, invasive ventilator-free survival, cardiac status, gross motor development, development of antibodies to rhGAA, and levels of urinary Glc(4). Following 52 weeks of treatment, 6/11 (54.5%) CRIM-negative and 1/21 (4.8%) CRIM-positive patients were deceased or invasively ventilated (p<0.0001). By age 27.1 months, all CRIM-negative patients and 4/21 (19.0%) CRIM-positive patients were deceased or invasively ventilated. Cardiac function and gross motor development improved significantly more in the CRIM-positive group. IgG antibodies to rhGAA developed earlier and serotiters were higher and more sustained in the CRIM-negative group. CRIM-negative status predicted reduced overall survival and invasive ventilator-free survival and poorer clinical outcomes in infants with Pompe disease treated with rhGAA. The effect of CRIM status on outcome appears to be mediated by antibody responses to the exogenous protein.


Assuntos
Reações Cruzadas , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Galactosidase/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Doença de Depósito de Glicogênio Tipo II/imunologia , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Força Muscular/efeitos dos fármacos , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , alfa-Galactosidase/genética , alfa-Galactosidase/imunologia
15.
J Occup Med Toxicol ; 4: 23, 2009 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-19698165

RESUMO

INTRODUCTION: While epidemiological methods have grown in sophistication during the 20th century, their application in historical occupational (and environmental) health research has also led to a corresponding growth in uncertainty in the validity and reliability of the attribution of risk in the resulting studies, particularly where study periods extend back in time to the immediate postwar era (1945-70) when exposure measurements were sporadic, unsystematically collected and primitive in technique; and, more so, to the pre-WWII era (when exposure data were essentially non-existent). These uncertainties propagate with animal studies that are designed to confirm the carcinogenicity by inhalation exposure of a chemical putatively responsible for historical workplace cancers since exact exposure conditions were never well characterized. In this report, we present a weight of scientific evidence examination of the human and toxicological evidence to show that soluble nickel is not carcinogenic; and, furthermore, that the carcinogenic potencies previously assigned by regulators to sulphidic and oxidic nickel compounds for the purposes of developing occupational exposure limits have likely been overestimated. METHODS: Published, file and archival evidence covering the pertinent epidemiology, biostatistics, confounding factors, toxicology, industrial hygiene and exposure factors, and other risky exposures were examined to evaluate the soluble nickel carcinogenicity hypothesis; and the likely contribution of a competing workplace carcinogen (arsenic) on sulphidic and oxidic nickel risk estimates. FINDINGS: Sharp contrasts in available land area and topography, and consequent intensity of production and refinery process layouts, likely account for differences in nickel species exposures in the Kristiansand (KNR) and Port Colborne (PCNR) refineries. These differences indicate mixed sulphidic and oxidic nickel and arsenic exposures in KNR's historical electrolysis department that were previously overlooked in favour of only soluble nickel exposure; and the absence of comparable insoluble nickel exposures in PCNR's tankhouse, a finding that is consistent with the absence of respiratory cancer risk there. The most recent KNR evidence linking soluble nickel with lung cancer risk arose in a reconfiguration of KNR's historical exposures. But the resulting job exposure matrix lacks an objective, protocol-driven rationale that could provide a valid and reliable basis for analyzing the relationship of KNR lung cancer risk with any nickel species. Evidence of significant arsenic exposure during the processing step in the Clydach refinery's hydrometallurgy department in the 1902-1934 time period likely accounts for most of the elevated respiratory cancer risk observed at that time. An understanding of the mechanism for nickel carcinogenicity remains an elusive goal of toxicological research; as does its capacity to confirm the human health evidence on this subject with animal studies. CONCLUDING REMARKS: Epidemiological methods have failed to accurately identify the source(s) of observed lung cancer risk in at least one nickel refinery (KNR). This failure, together with the negative long-term animal inhalation studies on soluble nickel and other toxicological evidence, strongly suggest that the designation of soluble nickel as carcinogenic should be reconsidered, and that the true causes of historical lung cancer risk at certain nickel refineries lie in other exposures, including insoluble nickel compounds, arsenic, sulphuric acid mists and smoking.

16.
Am J Med Genet A ; 149A(8): 1641-54, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19606472

RESUMO

The objective of our study was to assess the efficacy and safety of donepezil in young adults with Down syndrome (DS) but no evidence of Alzheimer disease (AD). A 12-week, randomized, double-blind, placebo-controlled study with a 12-week, open-label extension was conducted. The intervention consisted of donepezil (5-10 mg/day) in young adults (aged 18-35 years) with DS, but no AD. The primary measure was the Severe Impairment Battery (SIB) test and secondary measures were the Vineland Adaptive Behavior Scales (VABS), the Rivermead Behavioral Memory Test for Children, and the Clinical Evaluation of Language Fundamentals, Third Edition. At baseline, 123 subjects were randomly assigned treatment with donepezil or placebo. During the double-blind phase, SIB scores improved significantly from baseline in both groups, with no significant between-group differences. During the open-label phase, SIB scores in the original donepezil group remained stable; the original placebo group showed an improvement similar to that seen in the double-blind phase. VABS scores improved for donepezil, but not placebo, during the double-blind phase (observed cases, P = 0.03; last observation carried forward, P = 0.07). Post hoc responder analyses were significant for donepezil using three of five response definitions (P < or = 0.045). Adverse event rates were comparable to AD studies. In this first large-scale, multicenter trial of a pharmacological agent for DS, donepezil appears safe. Efficacy interpretation was limited for the primary measure due to apparent learning/practice and ceiling effects. Outcomes in post hoc analyses suggested efficacy in some, but not all subjects, consistent with phenotypic variability of DS. Additional studies are required to confirm potential benefits of donepezil in this population.


Assuntos
Síndrome de Down/tratamento farmacológico , Indanos/efeitos adversos , Indanos/uso terapêutico , Nootrópicos/efeitos adversos , Nootrópicos/uso terapêutico , Piperidinas/efeitos adversos , Piperidinas/uso terapêutico , Adulto , Demografia , Donepezila , Método Duplo-Cego , Feminino , Humanos , Indanos/farmacologia , Aprendizagem/efeitos dos fármacos , Masculino , Nootrópicos/farmacologia , Piperidinas/farmacologia , Resultado do Tratamento , Adulto Jovem
17.
Am J Med Genet A ; 143A(13): 1408-13, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17542008

RESUMO

There is growing evidence to support the use of early central cholinergic enhancement to improve cognitive functioning in individuals with Down syndrome (DS). This report summarizes preliminary safety and cognitive efficacy data for seven children (8-13 years) with DS who participated in a 22-week, open-label trial of donepezil hydrochloride. Donepezil was dosed once daily at 2.5 mg and, based on tolerability, increased to 5 mg/day. Safety assessments were conducted at Week 1 (baseline), Week 8 (2.5 mg donepezil), Week 16 (5 mg) and Week 22 (after the donepezil had been discontinued). Measures of cognitive function were administered at each visit, encompassing the following domains: memory; attention; mood; and adaptive functioning. Donepezil was well tolerated at the 2.5 and 5 mg doses. The side effects were mild, transient, and consistent with the adverse events noted with cholinesterase inhibitors. Some children showed improvement on measures of memory (NEPSY Memory for Names and Narrative Memory) and sustained attention to tasks (Conners' Parent Rating Scales), although increased irritability and/or assertiveness were noted in some patients. Overall, this clinical report series adds to our initial findings of language gains in children with DS treated with donepezil. It also supports the need for larger, double-blind studies of the safety and efficacy of donepezil and other cholinesterase inhibitors for children with DS.


Assuntos
Inibidores da Colinesterase/uso terapêutico , Cognição/efeitos dos fármacos , Síndrome de Down/tratamento farmacológico , Indanos/uso terapêutico , Piperidinas/uso terapêutico , Adolescente , Criança , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/efeitos adversos , Donepezila , Síndrome de Down/diagnóstico , Esquema de Medicação , Feminino , Humanos , Indanos/administração & dosagem , Indanos/efeitos adversos , Masculino , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Resultado do Tratamento
18.
Am J Med Genet C Semin Med Genet ; 142C(3): 187-95, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16838317

RESUMO

Clinical and translational research play a key role in the transition of basic research discoveries to effective therapies. In Down syndrome (DS), these research approaches are not well utilized or developed to test new therapies to improve cognitive and/or adaptive function in this population. This article reviews the history of clinical trial research in children with DS from a cognitive research perspective and discusses important issues relevant to the conduct of well designed clinical trials for this population. Specific issues addressed include: funding, study design, study medication, subject recruitment and retention, safety, and efficacy challenges. The Duke Down Syndrome Research Team's program of clinical research of cholinesterase inhibitors for individuals with DS serves as the model application for the identified research principles. It is hoped that this article will raise awareness of the unmet need for clinical research in the cognitive and adaptive function of individuals with DS, especially children with DS.


Assuntos
Cognição , Síndrome de Down/psicologia , Criança , Protocolos Clínicos , Ensaios Clínicos como Assunto/métodos , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Síndrome de Down/complicações , Síndrome de Down/tratamento farmacológico , Humanos , Nootrópicos/uso terapêutico , Seleção de Pacientes , Projetos de Pesquisa
19.
J Child Adolesc Psychopharmacol ; 16(6): 755-65, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17201619

RESUMO

Individuals with Down syndrome (DS) exhibit a cholinergic deficiency similar to that found in Alzheimer's disease. Cholinesterase inhibitors, used to treat Alzheimer's disease, may improve cognitive function in individuals with DS. This is the first investigation of the safety and efficacy of rivastigmine (an acetyl and butyryl cholinesterase inhibitor) on specific cognitive domains in pediatric DS. Eleven subjects with DS (ages 10-17 years) were treated with a liquid formulation of rivastigmine. Four subjects experienced no adverse events (AEs). Seven subjects reported AEs that were mild, transient and consistent with adverse events typically noted with cholinesterase inhibitors. Significant improvements were found in overall adaptive function (Vineland Adaptive Behavior Scales and Clinician's Interview-Based Impression of Change), attention (Leiter Attention Sustained tests A and B), memory (NEPSY: Narrative and Immediate Memory for Names subtests) and language (Test of Verbal Expression and Reasoning and Clinical Evaluation of Language Fundamentals-Preschool) domains. Improved language performance was found across all functional levels. These results underscore the need for larger, controlled studies employing a carefully constructed test battery capable of measuring the full scope of performance across multiple domains and a wide range of functional levels.


Assuntos
Inibidores da Colinesterase/uso terapêutico , Síndrome de Down/tratamento farmacológico , Fenilcarbamatos/uso terapêutico , Adaptação Psicológica/efeitos dos fármacos , Adolescente , Atenção/efeitos dos fármacos , Criança , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/efeitos adversos , Síndrome de Down/psicologia , Feminino , Humanos , Idioma , Masculino , Memória/efeitos dos fármacos , Cooperação do Paciente , Fenilcarbamatos/administração & dosagem , Fenilcarbamatos/efeitos adversos , Rivastigmina , Comportamento Verbal/efeitos dos fármacos
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