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1.
N Engl J Med ; 380(24): 2307-2316, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31059641

RESUMO

BACKGROUND: Huntington's disease is an autosomal-dominant neurodegenerative disease caused by CAG trinucleotide repeat expansion in HTT, resulting in a mutant huntingtin protein. IONIS-HTTRx (hereafter, HTTRx) is an antisense oligonucleotide designed to inhibit HTT messenger RNA and thereby reduce concentrations of mutant huntingtin. METHODS: We conducted a randomized, double-blind, multiple-ascending-dose, phase 1-2a trial involving adults with early Huntington's disease. Patients were randomly assigned in a 3:1 ratio to receive HTTRx or placebo as a bolus intrathecal administration every 4 weeks for four doses. Dose selection was guided by a preclinical model in mice and nonhuman primates that related dose level to reduction in the concentration of huntingtin. The primary end point was safety. The secondary end point was HTTRx pharmacokinetics in cerebrospinal fluid (CSF). Prespecified exploratory end points included the concentration of mutant huntingtin in CSF. RESULTS: Of the 46 patients who were enrolled in the trial, 34 were randomly assigned to receive HTTRx (at ascending dose levels of 10 to 120 mg) and 12 were randomly assigned to receive placebo. Each patient received all four doses and completed the trial. Adverse events, all of grade 1 or 2, were reported in 98% of the patients. No serious adverse events were seen in HTTRx-treated patients. There were no clinically relevant adverse changes in laboratory variables. Predose (trough) concentrations of HTTRx in CSF showed dose dependence up to doses of 60 mg. HTTRx treatment resulted in a dose-dependent reduction in the concentration of mutant huntingtin in CSF (mean percentage change from baseline, 10% in the placebo group and -20%, -25%, -28%, -42%, and -38% in the HTTRx 10-mg, 30-mg, 60-mg, 90-mg, and 120-mg dose groups, respectively). CONCLUSIONS: Intrathecal administration of HTTRx to patients with early Huntington's disease was not accompanied by serious adverse events. We observed dose-dependent reductions in concentrations of mutant huntingtin. (Funded by Ionis Pharmaceuticals and F. Hoffmann-La Roche; ClinicalTrials.gov number, NCT02519036.).


Assuntos
Proteína Huntingtina/antagonistas & inibidores , Doença de Huntington/tratamento farmacológico , Nucleotídeos/farmacologia , Oligonucleotídeos/uso terapêutico , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Proteína Huntingtina/líquido cefalorraquidiano , Proteína Huntingtina/genética , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Mutação , Nucleotídeos/síntese química , Oligonucleotídeos/líquido cefalorraquidiano
2.
N Engl J Med ; 377(3): 222-232, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28538111

RESUMO

BACKGROUND: Epidemiologic and genomewide association studies have linked loss-of-function variants in ANGPTL3, encoding angiopoietin-like 3, with low levels of plasma lipoproteins. METHODS: We evaluated antisense oligonucleotides (ASOs) targeting Angptl3 messenger RNA (mRNA) for effects on plasma lipid levels, triglyceride clearance, liver triglyceride content, insulin sensitivity, and atherosclerosis in mice. Subsequently, 44 human participants (with triglyceride levels of either 90 to 150 mg per deciliter [1.0 to 1.7 mmol per liter] or >150 mg per deciliter, depending on the dose group) were randomly assigned to receive subcutaneous injections of placebo or an antisense oligonucleotide targeting ANGPTL3 mRNA in a single dose (20, 40, or 80 mg) or multiple doses (10, 20, 40, or 60 mg per week for 6 weeks). The main end points were safety, side-effect profile, pharmacokinetic and pharmacodynamic measures, and changes in levels of lipids and lipoproteins. RESULTS: The treated mice had dose-dependent reductions in levels of hepatic Angptl3 mRNA, Angptl3 protein, triglycerides, and low-density lipoprotein (LDL) cholesterol, as well as reductions in liver triglyceride content and atherosclerosis progression and increases in insulin sensitivity. After 6 weeks of treatment, persons in the multiple-dose groups had reductions in levels of ANGPTL3 protein (reductions of 46.6 to 84.5% from baseline, P<0.01 for all doses vs. placebo) and in levels of triglycerides (reductions of 33.2 to 63.1%), LDL cholesterol (1.3 to 32.9%), very-low-density lipoprotein cholesterol (27.9 to 60.0%), non-high-density lipoprotein cholesterol (10.0 to 36.6%), apolipoprotein B (3.4 to 25.7%), and apolipoprotein C-III (18.9 to 58.8%). Three participants who received the antisense oligonucleotide and three who received placebo reported dizziness or headache. There were no serious adverse events. CONCLUSIONS: Oligonucleotides targeting mouse Angptl3 retarded the progression of atherosclerosis and reduced levels of atherogenic lipoproteins in mice. Use of the same strategy to target human ANGPTL3 reduced levels of atherogenic lipoproteins in humans. (Funded by Ionis Pharmaceuticals; ClinicalTrials.gov number, NCT02709850 .).


Assuntos
Angiopoietinas/antagonistas & inibidores , Aterosclerose/tratamento farmacológico , Doença da Artéria Coronariana/genética , Dislipidemias/tratamento farmacológico , Lipídeos/sangue , Oligonucleotídeos Antissenso/uso terapêutico , Oligonucleotídeos/uso terapêutico , Adulto , Idoso , Proteína 3 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/genética , Animais , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Doença da Artéria Coronariana/metabolismo , Modelos Animais de Doenças , Método Duplo-Cego , Dislipidemias/sangue , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Pessoa de Meia-Idade , Oligonucleotídeos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , RNA Mensageiro/antagonistas & inibidores
3.
Materials (Basel) ; 8(11): 7900-7912, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-28793686

RESUMO

Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 1013 to 105 Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods.

4.
Gac. méd. Méx ; 134(4): 385-96, jul.-ago. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-232770

RESUMO

El presente trabajo explora la digitalización de imágenes de "western blot" (WB) para extraer mayor información acerca de la respuesta inmune humoral del paciente infectado por el virus de la inmunodeficiencia adquirida humana (VIH) y analizar de manara multivariada los datos obtenidos. Se realizó la digitalización y análisis de las imágenes de WB de 115 sueros. Con estos datos se hicieron análisis tanto cualitativos: dendograma y análisis de componentes principales (ACP), como cuantitativos: ACP con el total de bandas tomando sólo los antígenos propios del virus o utilizando los antígenos que no pertenecen al virus. Los resultados demuestran la factibilidad de diagnosticar de forma mecánica un número grande de imágenes de WB. Tanto el dendograma como el ACP cualitativo separaron, de manera adecuada, imágenes blancas, imágenes con menos de cuatro bandas e imágenes con patrones más complejos. El análisis cuantitativo, que conserva más información, separa perfectamente imágenes de diagnóstico negativo, indeterminado y positivo. Además, se encontró que las imágenes con patrones complejos correlacionan más con individuos asintomáticos. Este análisis reveló también la existencia de banda que no parecen corresponder a proteínas virales, mismas que pudieran corresponder a autoantígenos o antígenos cruzados entre el VIH y el ser humano, dando cauce a autoinmunidad. El análisis digital de imágenes de WB en el caso del VIH, prueba así su gran utilidad en el diagnóstico de caso y en el seguimiento de la evolución y patogenia de la enfermedad


Assuntos
Humanos , Western Blotting , Sorodiagnóstico da AIDS/métodos
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