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1.
Muscle Nerve ; 66(4): 508-512, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35778789

RESUMO

INTRODUCTION/AIMS: Disease progression in myotonic dystrophy (DM) is marked by milestone events when functional thresholds are crossed. DM type 2 (DM2) is considered less severe than DM type 1 (DM1), but it is unknown whether this applies uniformly to all features. We compared the age-dependent risk for milestone events in DM1 and DM2 and tested for associations with age of onset and sex. METHODS: We studied a large cohort of adult participants in a national registry of DM1 and DM2. Using annual surveys from participants, we ascertained milestone events for motor involvement (use of cane, walker, ankle brace, wheelchair, or ventilatory device), systemic involvement (diabetes, pacemaker, cancer), loss of employment due to DM, and death. RESULTS: Mean follow-up of registry participants (929 DM1 and 222 DM2 patients) was 7 years. Disability and motor milestones occurred at earlier ages in DM1 than in DM2. In contrast, the risk of diabetes was higher and tended to occur earlier in DM2 (hazard ratio [HR], 0.56; P ≤ .001). In DM1, the milestone events tended to occur earlier, and life expectancy was reduced, when symptoms began at younger ages. In DM1, men were at greater risk for disability (HR, 1.34; P ≤ .01), use of ankle braces (HR, 1.41; P = .02), and diabetes (HR, 2.2; P ≤ .0001), whereas women were at greater risk for needing walkers (HR, 0.68; P = .001) or malignancy (HR, 0.66; P ≤ .01). DISCUSSION: Milestone events recorded through registries can be used to assess long-term impact of DM in large cohorts. Except for diabetes, the age-related risk of milestone events is greater in DM1 than in DM2.


Assuntos
Diabetes Mellitus Tipo 2 , Distrofia Miotônica , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Distrofia Miotônica/diagnóstico , Sistema de Registros
2.
Langmuir ; 34(9): 2989-2995, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29432688

RESUMO

Silicon- and oxygen-containing hydrogenated amorphous carbon (a-C:H:Si:O) coatings are amorphous thin-film materials composed of hydrogenated amorphous carbon (a-C:H), doped with silicon and oxygen. Compared to a-C:H, a-C:H:Si:O exhibits much lower susceptibility to oxidative degradation and higher thermal stability, making a-C:H:Si:O attractive for many applications. However, the physical mechanisms for this improved behavior are not understood. Here, the thermally induced structural evolution of a-C:H:Si:O was investigated in situ by X-ray photoelectron and absorption spectroscopy, as well as molecular dynamics (MD) simulations. The spectroscopy results indicate that upon high vacuum annealing, two thermally activated processes with a Gaussian distribution of activation energies with mean value E and standard deviation σ take place in a-C:H:Si:O: (a) ordering and clustering of sp2 carbon ( E ± σ = 0.22 ± 0.08 eV) and (b) conversion of sp3- to sp2-bonded carbon ( E ± σ = 3.0 ± 1.1 eV). The experimental results are in qualitative agreement with the outcomes of MD simulations performed using a ReaxFF potential. The MD simulations also indicate that the higher thermal stability of a-C:H:Si:O compared to a-C:H (with similar fraction of sp2-bonded carbon and hydrogen content) derives from the significantly lower fraction of strained carbon-carbon sp3 bonds in a-C:H:Si:O compared to a-C:H, which are more likely to break at elevated temperatures.

3.
Muscle Nerve ; 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29328504

RESUMO

INTRODUCTION: When preparing for clinical trials in myotonic dystrophy type-1 (DM1), it is important that researchers develop and identify patient-reported outcome measures with good measurement properties. METHODS: Fifty-two DM1 patients enrolled in 2 clinical studies completed the Myotonic Dystrophy Health Index (MDHI), 36-Item Short Form Health Survey (version 2; SF-36v2), Individualized Neuromuscular Quality of Life questionnaire (INQoL), and a questionnaire comparing the relevance, usability, overall preference, and perceived responsiveness of each measure. The associations between instrument scores and physical function, genetic test results, and employment status were examined. RESULTS: The MDHI was preferred over the INQoL in 13 of 13 areas and was preferred over the SF-36v2 in 9 of 13 areas. The MDHI was the only score that was associated with participant employment status, CTG repeat length, and the 3 measurements of clinical function. DISCUSSION: The MDHI correlates well with physical function and is viewed favorably by participants in DM1 clinical studies. Muscle Nerve, 2018.

4.
Eur J Clin Pharmacol ; 74(2): 161-169, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127458

RESUMO

PURPOSE: The CD40-CD40L pathway is a promising treatment target for autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus and lupus nephritis. The safety, pharmacokinetics and pharmacodynamics of BI 655064, a novel humanised antagonistic anti-CD40 monoclonal antibody, were investigated in this first-in-human trial. METHODS: Healthy male subjects (n = 72) were randomised 3:1, within each BI 655064 dose group, to single intravenous (IV; 0.2-120 mg) or subcutaneous (SC; 40-120 mg) doses of BI 655064 or placebo. Safety, plasma exposure, CD40 receptor occupancy and CD40L-induced CD54 upregulation were assessed over 12 weeks. RESULTS: Adverse events (AEs) were reported in 43% of subjects (n = 31). Frequency and intensity of AEs were generally similar between BI 655064 and placebo and showed no dose relationship. The most frequent AEs were headache and nasopharyngitis. One mild rash and one local reaction occurred with SC BI 655064; two serious AEs were reported, both judged unrelated to BI 655064. Pharmacokinetic evaluation demonstrated a more than proportional increase in plasma exposure relative to BI 655064 dose, with a terminal half-life between 4 h and 4 days IV and approximately 5 days SC; doses ≥ 20 mg IV and 120 mg SC showed > 90% CD40 receptor occupancy and inhibition of CD54 upregulation, which lasted 7 days in the 120 mg IV and SC groups. CONCLUSIONS: Single doses up to 120 mg BI 655064 IV and SC were well tolerated and showed a high potential to block the CD40-CD40L pathway, supporting further clinical development of BI 655064 in patients with autoimmune disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01510782.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Antígenos CD40/antagonistas & inibidores , Administração Intravenosa , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/farmacologia , Ligante de CD40/farmacologia , Relação Dose-Resposta a Droga , Voluntários Saudáveis , Humanos , Injeções Subcutâneas , Molécula 1 de Adesão Intercelular/biossíntese , Masculino , Pessoa de Meia-Idade , Ensaio Radioligante , Método Simples-Cego , Adulto Jovem
5.
Allergy Asthma Proc ; 38(2): 157-164, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28234053

RESUMO

BACKGROUND: Asthma is characterized by a complex interaction of inflammatory mediators. The prostaglandin D2 receptor, chemoattractant receptor-homologous molecule on Th2 cells (CRTH2), plays a pivotal role in the pathogenesis of allergic airway inflammation. OBJECTIVE: To ealuate the efficacy, safety, and pharmacokinetics of BI 671800, a CRTH2 antagonist, when added to inhaled corticosteroid therapy in adult patients with symptomatic asthma. METHODS: In this phase IIa, 12-week, randomized, double-blind, three-period, four-treatment, incomplete block crossover trial, BI 671800 was administered either as a single 400-mg dose in the morning (A.M.) or evening (P.M.), or 200 mg twice daily (A.M. and P.M.) versus placebo, together with fluticasone propionate (44 µg, two inhalations twice daily). The primary end point was the change from baseline in trough forced expiratory volume in 1 second percentage predicted after 4 weeks. The secondary end point was the change in Asthma Control Questionnaire score from baseline. RESULTS: A total of 108 patients were randomized and treated. After 4 weeks, the adjusted mean (± SE) treatment differences for the primary end point versus placebo were 0.08 ± 0.62%, 0.28 ± 0.61%, and 0.67 ± 0.63% for BI 671800 at 200 mg twice daily, 400 mg A.M., and 400 mg P.M., respectively (not statistically significant). No statistically significant or clinically meaningful differences in the Asthma Control Questionnaire score were observed versus placebo. Each treatment was well tolerated. CONCLUSION: BI 671800 at a dose of 400 mg administered for 4 weeks with fluticasone propionate did not provide clinical improvement in patients with asthma; reasons for this are unclear, but it may be due to insufficient inhibition of the CRTH2 receptor at the doses used.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Benzamidas/uso terapêutico , Pirimidinas/uso terapêutico , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Adulto , Anti-Inflamatórios/uso terapêutico , Asma/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fluticasona/uso terapêutico , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Capacidade Vital
6.
Muscle Nerve ; 53(2): 183-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26044513

RESUMO

INTRODUCTION: The Myotonic Dystrophy Health Index (MDHI) is a disease-specific patient-reported outcome measure. Here, we examine the associations between the MDHI and other measures of disease burden in a cohort of individuals with myotonic dystrophy type-1 (DM1). METHODS: We conducted a cross-sectional study of 70 patients with DM1. We examined the associations between MDHI total and subscale scores and scores from other clinical tests. Participants completed assessments of strength, myotonia, motor and respiratory function, ambulation, and body composition. Participants also provided blood samples, underwent physician evaluations, and completed other patient-reported outcome measures. RESULTS: MDHI total and subscale scores were strongly associated with muscle strength, myotonia, motor function, and other clinical measures. CONCLUSIONS: Patient-reported health status, as measured by the MDHI, is associated with alternative measures of clinical health. These results support the use of the MDHI as a valid tool to measure disease burden in DM1 patients.


Assuntos
Distrofia Miotônica/diagnóstico , Distrofia Miotônica/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Índice de Gravidade de Doença , Absorciometria de Fóton , Adulto , Idoso , Creatina Quinase/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Exame Neurológico , Estatística como Assunto , Adulto Jovem
7.
Dev Med Child Neurol ; 58(7): 698-705, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26510705

RESUMO

AIM: The frequency and impact of symptoms experienced by patients with congenital, childhood, and juvenile-onset myotonic dystrophy (CDM/ChDM/JDM) is not documented. This report identifies symptomatic areas with the greatest disease burden in an international population of patients with early-onset myotonic dystrophy type-1 (DM1). METHOD: We distributed surveys to parents of patients with CDM/ChDM/JDM. Patients with CDM/ChDM/JDM were members of the US National Registry of DM1 Patients and Family Members, the Canadian Neuromuscular Disease Registry, or the Swedish Health System. Surveys inquired about 325 symptoms and 20 themes associated with CDM/ChDM/JDM. Parents identified the importance of each symptom and theme to their affected child. The prevalence of each symptom and theme were compared across subgroups of patients. The statistical analysis was performed using Fisher's exact and Kruskal-Wallis tests. RESULTS: One hundred and fifty parents returned surveys. The most frequently reported symptomatic themes in children were issues involving communication (81.7%) and problems with hands or fingers (79.6%). Problems with communication and fatigue were the issues that were reported to have the greatest impact on childrens' lives, while 24.1% of children reported cardiac disorders and 15.8% had problems with anesthesia. INTERPRETATION: A range of symptoms contribute to the burden of disease faced by children with DM1. Many of these symptoms are under-recognized.


Assuntos
Cooperação Internacional , Distrofia Miotônica/fisiopatologia , Distrofia Miotônica/psicologia , Pais/psicologia , Adolescente , Idade de Início , Criança , Transtornos da Comunicação/etiologia , Fadiga/etiologia , Feminino , Gastroenteropatias/etiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Distrofia Miotônica/epidemiologia , Qualidade de Vida/psicologia
8.
Invest New Drugs ; 33(2): 409-22, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25529193

RESUMO

Purpose BI 831266 is a potent, selective, low-molecular-weight inhibitor of Aurora kinase B. This trial aimed to determine the maximum tolerated dose (MTD) of BI 831266 in patients with advanced solid tumors (NCT00756223; EudraCT 2008-001631-36; 1257.1). Methods BI 831266 (4-130 mg) was administered over 24 h on days 1 and 15 of a 4-week schedule. A modified 3 + 3 dose-escalation design was utilized to evaluate the MTD. Safety, pharmacokinetics, pharmacodynamics, objective response rate, progression-free survival (PFS) and exploratory biomarkers were secondary endpoints. Results Twenty-five patients received BI 831266. The most frequent tumor type was colorectal cancer (48%). One patient (130 mg) experienced a dose-limiting toxicity of grade 3 febrile neutropenia. The trial was prematurely terminated (sponsor decision) without further dose-escalation. The most frequent treatment-related adverse events (AEs) were fatigue (20%), neutropenia, alopecia (16% each), anemia, dry skin, and nausea (12% each). Treatment-related grade ≥3 AEs were neutropenia (12%), anemia (8%), and febrile neutropenia (4%); 15 patients experienced serious AEs. High variability in the pharmacokinetic profiles precluded definitive pharmacokinetic conclusions. Exploratory biomarker determination revealed consistency with the mode of action as an Aurora kinase B inhibitor. One patient (4%; 32 mg) with cervical cancer demonstrated a confirmed partial response (duration 141 days, PFS 414 days). Four patients had stable disease. Conclusion The MTD of BI 831266 was not reached because of early trial termination. BI 831266 demonstrated a generally manageable safety profile and signs of antitumor activity in some patients' solid tumors.


Assuntos
Antineoplásicos/farmacologia , Aurora Quinase B/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/farmacologia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Serina-Treonina Quinases/administração & dosagem , Proteínas Serina-Treonina Quinases/efeitos adversos , Proteínas Serina-Treonina Quinases/farmacocinética
9.
J Allergy Clin Immunol ; 133(2): 414-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24332218

RESUMO

BACKGROUND: The inflammatory response in patients with seasonal allergic rhinitis (SAR) is partly mediated by the prostaglandin D2 receptor chemoattractant receptor homologous molecule on T(H)2 cells (CRTH2). OBJECTIVE: We sought to investigate the efficacy and safety of the oral CRTH2 antagonist BI 671800 (50, 200, and 400 mg twice daily), fluticasone propionate nasal spray (200 µg once daily), or oral montelukast (10 mg once daily) administered for 2 weeks in patients with SAR. METHODS: In this randomized, double-blind, placebo-controlled, partial-crossover study, participants aged 18 to 65 years with a positive skin prick test to Dactylis glomerata pollen were exposed to out-of-season allergen in the environmental challenge chamber for 6 hours. The primary efficacy variable was the total nasal symptom score assessed as the area under the curve (AUC)(0-6h). RESULTS: In total, 146 patients (63.7% male; mean age, 36.1 years) were randomized. The adjusted mean total nasal symptom score AUC(0-6h) was significantly reduced versus placebo with 200 mg of BI 671800 (absolute difference, -0.85; percentage difference, -17%; P = .0026), montelukast (absolute difference, -0.74; percentage difference, -15%; P = .0115), and fluticasone propionate (absolute difference, -1.64; percentage difference, -33%; P < .0001). Compared with placebo, BI 671800 significantly reduced nasal eosinophil values (P < .05 for all doses), significantly inhibited nasal inflammatory cytokine levels (IL-4 and eotaxin, P < .05; 200 mg twice daily), and induced a dose-related reduction in ex vivo prostaglandin D2-mediated eosinophil shape change. CONCLUSION: Two hundred milligrams of BI 671800 twice daily demonstrated efficacy in treating SAR symptoms induced by environmental challenge chamber allergen exposure and had a favorable safety profile.


Assuntos
Antialérgicos/uso terapêutico , Benzamidas/uso terapêutico , Pirimidinas/uso terapêutico , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Rinite Alérgica Sazonal/tratamento farmacológico , Adulto , Alérgenos/imunologia , Antialérgicos/farmacologia , Benzamidas/farmacologia , Estudos Cross-Over , Citocinas/imunologia , Método Duplo-Cego , Eosinófilos/citologia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/citologia , Mucosa Nasal/imunologia , Poaceae/imunologia , Pólen/imunologia , Pirimidinas/farmacologia , Receptores Imunológicos/imunologia , Receptores de Prostaglandina/imunologia , Rinite Alérgica Sazonal/imunologia , Resultado do Tratamento
11.
Muscle Nerve ; 49(6): 906-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24142420

RESUMO

INTRODUCTION: In preparation for clinical trials we examine the validity, reliability, and patient understanding of the Myotonic Dystrophy Health Index (MDHI). METHODS: Initially we partnered with 278 myotonic dystrophy type-1 (DM1) patients and identified the most relevant questions for the MDHI. Next, we used factor analysis, patient interviews, and test-retest reliability assessments to refine and evaluate the instrument. Lastly, we determined the capability of the MDHI to differentiate between known groups of DM1 participants. RESULTS: Questions in the final MDHI represent 17 areas of DM1 health. The internal consistency was acceptable in all subscales. The MDHI had a high test-retest reliability (ICC = 0.95) and differentiated between DM1 patient groups with different disease severities. CONCLUSIONS: Initial evaluation of the MDHI provides evidence that it is valid and reliable as an outcome measure for assessing patient-reported health. These results suggest that important aspects of DM1 health may be measured effectively using the MDHI.


Assuntos
Avaliação da Deficiência , Distrofia Miotônica/diagnóstico , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados da Assistência ao Paciente , Índice de Gravidade de Doença , Adulto , Idoso , Efeitos Psicossociais da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autorrelato/normas , Inquéritos e Questionários/normas , Estados Unidos
12.
JAMA ; 306(22): 2480-6, 2011 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-22166607

RESUMO

CONTEXT: Myotonic muscular dystrophy (MMD) is an autosomal-dominant multisystem neuromuscular disorder characterized by unstable nucleotide repeat expansions. Case reports have suggested that MMD patients may be at increased risk of malignancy, putative risks that have never been quantified. OBJECTIVE: To quantitatively evaluate cancer risk in patients with MMD, overall and by sex and age. DESIGN, SETTING, AND PARTICIPANTS: We identified 1658 patients with an MMD discharge diagnosis in the Swedish Hospital Discharge Register or Danish National Patient Registry between 1977 and 2008. We linked these patients to their corresponding cancer registry. Patients were followed up from date of first MMD-related inpatient or outpatient contact to first cancer diagnosis, death, emigration, or completion of cancer registration. MAIN OUTCOME MEASURES: Risks of all cancers combined and by anatomic site, stratified by sex and age. RESULTS: One hundred four patients with an inpatient or outpatient discharge diagnosis of MMD developed cancer during postdischarge follow-up. This corresponds to an observed cancer rate of 73.4 per 10,000 person-years in MMD vs an expected rate of 36.9 per 10,000 person-years in the general Swedish and Danish populations combined (standardized incidence ratio [SIR], 2.0; 95% CI, 1.6-2.4). Specifically, we observed significant excess risks of cancers of the endometrium (n = 11; observed rate, 16.1/10,000 person-years; SIR, 7.6; 95% CI, 4.0-13.2), brain (n = 7; observed rate, 4.9/10,000 person-years; SIR, 5.3; 95% CI, 2.3-10.4), ovary (n = 7; observed rate, 10.3/10,000 person-years; SIR, 5.2; 95% CI, 2.3-10.2), and colon (n = 10; observed rate, 7.1/10,000 person-years; SIR, 2.9; 95% CI, 1.5-5.1). Cancer risks were similar in women and men after excluding genital organ tumors (SIR, 1.9; 95% CI, 1.4-2.5, vs SIR, 1.8; 95% CI, 1.3-2.5, respectively; P = .81 for heterogeneity; observed rates, 64.5 and 47.7 per 10,000 person-years in women and men, respectively). The same pattern of cancer excess was observed first in the Swedish and then in the Danish cohorts, which were studied sequentially and initially analyzed independently. CONCLUSION: Patients with MMD identified from the Swedish and Danish patient registries were at increased risk of cancer both overall and for selected anatomic sites.


Assuntos
Distrofia Miotônica/epidemiologia , Neoplasias/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Comorbidade , Dinamarca/epidemiologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Risco , Fatores Sexuais , Suécia/epidemiologia , Adulto Jovem
13.
ACS Appl Mater Interfaces ; 13(10): 12610-12621, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33656848

RESUMO

The incorporation of silicon and oxygen into hydrogenated amorphous carbon (a-C:H) is an effective approach to decrease the dependence of the tribological properties of a-C:H on the environment. Here, we evaluate the effect of hydrogen and oxygen partial pressures in vacuum on the tribological response of steel pins sliding against films consisting of silicon- and oxygen-containing a-C:H (a-C:H:Si:O). Experiments are conducted in the low-friction/low-wear regime, where sufficient gas pressure prevents steel from adhering to the a-C:H:Si:O, with the velocity accommodation mode being interfacial sliding between the tribotrack formed in the a-C:H:Si:O film and the carbonaceous tribofilm that is formed on the countersurface. The experiments indicated a decrease (increase) in friction and wear with the hydrogen (oxygen) pressure (hydrogen pressures between 50 and 2000 mbar; oxygen pressures between 10 and 1000 mbar). Characterization by X-ray photoelectron and absorption spectroscopies indicated the occurrence of tribologically induced rehybridization of carbon-carbon bonds from sp3 to sp2. This mechanically induced structural transformation coincided with the dissociative surface reaction between hydrogen (oxygen) gas molecules and sp2 carbon-carbon bonds that are highly strained, which results in the formation of carbon-hydrogen groups (carbonyl or ether groups together with silicon atoms having higher oxidation states). On the basis of variations of the fraction of these surface functional groups with gas pressure, a phenomenological model is proposed for the gas pressure dependence of friction for steel when sliding on a-C:H:Si:O films: while the decrease in friction with hydrogen pressure is induced by an increase in the percentage of carbon-hydrogen groups, the increase in friction with oxygen pressure is caused by a progressive increase in the relative fraction of silicon atoms having higher oxidation states and an increase in surface oxygen concentration.

14.
Neurology ; 96(2): e228-e240, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046619

RESUMO

OBJECTIVE: To assess mexiletine's long-term safety and effect on 6-minute walk distance in a well-defined cohort of patients with myotonic dystrophy type 1 (DM1). METHODS: We performed a randomized, double-blind, placebo-controlled trial of mexiletine (150 mg 3 times daily) to evaluate its efficacy and safety in a homogenous cohort of adult ambulatory patients with DM1. The primary outcome was change in 6-minute walk distance at 6 months. Secondary outcomes included changes in hand grip myotonia, strength, swallowing, forced vital capacity, lean muscle mass, Myotonic Dystrophy Health Index scores, and 24-hour Holter and ECG results at 3 and 6 months. RESULTS: Forty-two participants were randomized and 40 completed the 6-month follow-up (n = 20 in both groups). No significant effects of mexiletine were observed on 6-minute walk distance, but hand grip myotonia was improved with mexiletine treatment. There were no differences between the mexiletine and placebo groups with respect to the frequency or type of adverse events. Changes in PR, QRS, and QTc intervals were similar in mexiletine- and placebo-treated participants. CONCLUSIONS: There was no benefit of mexiletine on 6-minute walk distance at 6 months. Although mexiletine had a sustained positive effect on objectively measured hand grip myotonia, this was not seen in measures reflecting participants' perceptions of their myotonia. No effects of mexiletine on cardiac conduction measures were seen over the 6-month follow-up period. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for ambulatory patients with DM1, mexiletine does not significantly change 6-minute walk distance at 6 months.


Assuntos
Força da Mão/fisiologia , Mexiletina/uso terapêutico , Distrofia Miotônica/tratamento farmacológico , Distrofia Miotônica/fisiopatologia , Bloqueadores do Canal de Sódio Disparado por Voltagem/uso terapêutico , Teste de Caminhada/tendências , Adulto , Estudos de Coortes , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Eletrocardiografia/tendências , Feminino , Humanos , Masculino , Mexiletina/farmacologia , Pessoa de Meia-Idade , Distrofia Miotônica/diagnóstico , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Teste de Caminhada/métodos
15.
Cancer Causes Control ; 20(10): 2009-20, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19642006

RESUMO

Tumorigenesis is a multi-step process due to an accumulation of genetic mutations in multiple genes in diverse pathways which ultimately lead to loss of control over cell growth. It is well known that inheritance of rare germline mutations in genes involved in tumorigenesis pathways confer high lifetime risk of neoplasia in affected individuals. Furthermore, a substantial number of multiple malformation syndromes include cancer susceptibility in their phenotype. Studies of the mechanisms underlying these inherited syndromes have added to the understanding of both normal development and the pathophysiology of carcinogenesis. Myotonic dystrophy (DM) represents a group of autosomal dominant, multisystemic diseases that share the clinical features of myotonia, muscle weakness, and early-onset cataracts. Myotonic dystrophy type 1 (DM1) and myotonic dystrophy type 2 (DM2) result from unstable nucleotide repeat expansions in their respective genes. There have been multiple reports of tumors in individuals with DM, most commonly benign calcifying cutaneous tumors known as pilomatricomas. We provide a summary of the tumors reported in DM and a hypothesis for a possible mechanism of tumorigenesis. We hope to stimulate further study into the potential role of DM genes in tumorigenesis, and help define DM pathogenesis, and facilitate developing novel treatment modalities.


Assuntos
Distrofia Miotônica/complicações , Distrofia Miotônica/epidemiologia , Neoplasias/complicações , Neoplasias/epidemiologia , Formação de Conceito , Suscetibilidade a Doenças , Humanos , Modelos Biológicos , Neoplasias/etiologia , Fatores de Risco
16.
Front Neurol ; 10: 1071, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681146

RESUMO

Introduction: Recent evidence demonstrates that women with myotonic dystrophy type 1 are at increased risk of reproductive organ tumors. However, studies of reproductive cancer risk factors in those patients are lacking. Methods: Using questionnaires, we collected and analyzed personal history information related to cancer risk factors from women enrolled in a UK and US registry for myotonic dystrophy (dystrophia myotonica; DM) patients. Results: The survey was completed by 242 DM type 1 (DM1) and 44 DM type 2 (DM2) women enrolled in the UK Registry (N = 124) and the US National Registry (N = 162). The mean age at DM1 diagnosis was 33.8 years (standard deviation, SD = 13.2) and for DM2 was 49.2 (SD = 13.0). Mean age at survey was 48.7 (SD = 12.8) and 59.1 years (SD = 12.8) for DM1 and DM2, respectively. There were no statistically significant differences between DM1 and DM2 regarding menstrual history or fertility-related factors. Yet, women with DM2 were more likely to have used menopausal hormone therapy (HT) than women with DM1 (52.3 vs. 22.1%, p < 0.0001), and more women with DM2 had a hysterectomy (53.5 vs. 29.5%, p < 0.01). These differences were not statistically significant after age adjustment (OR = 2.00, p = 0.08, and OR = 1.40, p = 0.38, respectively). The frequency of self-reported reproductive organ tumors was not significantly different comparing DM1 to DM2 (p = 0.28). However, the data suggested that women with DM2 appear to have a lower risk of malignant tumors compared to those with DM1 (OR = 0.72, p = 0.69). Discussion: Our study is the first to characterize a wide range of reproductive risk factors in women with DM. We observed no significant differences between DM1 and DM2 in the factors that were evaluated, which suggests that the known excesses of ovarian and endometrial cancer previously reported in women with DM1 cannot be attributed to greater prevalence of standard cancer-related reproductive risk factors. Larger studies evaluating the possible link between reproductive cancer risk factors and risk of tumors in women with DM are needed.

17.
Neurol Clin Pract ; 9(4): 343-353, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31583190

RESUMO

PURPOSE OF REVIEW: Myotonic dystrophy type 2 (DM2) is a rare, progressive multisystem disease particularly affecting the skeletal muscle. A causal therapy is not yet available; however, prompt, appropriate symptomatic treatments are essential to limit disease-related complications. Evidence-based guidelines to assist medical practitioners in the care of DM2 patients do not exist. RECENT FINDINGS: The Myotonic Dystrophy Foundation (MDF) previously worked with an international group of 66 clinicians to develop consensus-based care recommendations for myotonic dystrophy type 1. Following a similar approach, the MDF recruited 15 international clinicians with long-standing experience in the care of DM2 patients to develop consensus-based care recommendations. The single text procedure was adopted. This process generated a 4-page Quick Reference Guide and a comprehensive 55-page document that provides care recommendations for DM2 patients. SUMMARY: The resulting recommendations will help standardize and improve care for DM2 patients and facilitate appropriate management in centers without neuromuscular specialists.

20.
J Clin Pharmacol ; 58(12): 1566-1577, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30113724

RESUMO

BI 655064 is a humanized antagonistic anti-cluster of differentiation (CD) 40 monoclonal antibody that selectively blocks the CD40-CD40L interaction. The CD40-CD40L pathway is a promising treatment target for autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and lupus nephritis. The safety, tolerability, pharmacokinetics, and pharmacodynamics of repeated once-weekly BI 655064 subcutaneous dosing over 4 weeks were evaluated in a multiple-dose study in healthy subjects. Subjects (N = 40) were randomized 4:1 to four sequential BI 655064 dose groups (80, 120, 180, 240 mg) or to placebo. Safety and tolerability, plasma exposure, CD40 receptor occupancy, and CD40L-induced CD54 upregulation were assessed over 64 and 78 days for the 80- to 180-mg and 240-mg dose groups, respectively. BI 655064 exposure increased in a supraproportional manner, due to target-mediated drug clearance, for doses between 80 mg and 120 mg, but was near proportional for doses greater than 120 mg. Terminal half-life ranged between 6 and 8 days. Dose-dependent accumulation of BI 655064 supports the use of a loading dose in future clinical studies. Following 4 weeks of dosing, >90% CD40 receptor occupancy and inhibition of CD54 upregulation were observed at all dose levels, lasting for 17 days after the last dose. BI 655064 was generally well tolerated. There were no serious adverse events and the frequency and intensity of adverse events were similar for BI 655064 and placebo; no dose relationship or relevant signs of an acute immune reaction were observed. These findings support further investigation of BI 655064 as a potential treatment for autoimmune diseases.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Doenças Autoimunes/terapia , Antígenos CD40/imunologia , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
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