Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Cephalalgia ; 36(9): 887-98, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27269043

RESUMO

AIM: The aim of this trial was to evaluate the efficacy and tolerability of ubrogepant (MK-1602), a calcitonin gene-related peptide receptor antagonist (CGRP-RA), for the acute treatment of migraine. METHODS: This double-blind, placebo-controlled study randomized 834 participants to treat one migraine attack with ubrogepant 1 mg, 10 mg, 25 mg, 50 mg, 100 mg, or placebo in a 1:1 ratio. The co-primary endpoints were pain freedom and headache response at two hours. The first primary hypothesis tested the dose-response trend for two-hour pain freedom using a logistic regression model. Subsequent hypotheses tested the effects of each dose on the co-primary endpoints, using a closed sequential testing procedure to control for multiplicity. RESULTS: A total of 527 participants received ubrogepant and 113 received placebo. A positive response trend in the proportion of participants achieving two-hour pain freedom was demonstrated (p < 0.001). Ubrogepant 100 mg was significantly superior to placebo for two-hour pain freedom (25.5% vs 8.9%) but not for two-hour headache response. Per the prespecified multiplicity strategy, this nonsignificant result precluded further formal hypothesis testing, although the 50 mg and 25 mg doses demonstrated nominal significance over placebo for two-hour pain freedom (unadjusted p < 0.05). Overall, adverse events were similar between ubrogepant and placebo. CONCLUSION: This trial supports ubrogepant's efficacy and provides further evidence that CGRP-RAs are viable options for the acute treatment of migraine.


Assuntos
Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Transtornos de Enxaqueca/tratamento farmacológico , Piridinas/uso terapêutico , Pirróis/uso terapêutico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Epilepsy Behav ; 51: 321-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26340046

RESUMO

PURPOSE: Periventricular nodular heterotopia (PVNH) is a malformation of cortical development due to impaired neuronal migration resulting in the formation of nodular masses of neurons and glial cells in close proximity to the ventricular walls. We report the clinical characteristics of the largest case series of FLNA-negative patients with seizures and bilateral periventricular heterotopia. METHODS: Participants were recruited through the Epilepsy Phenome/Genome Project (EPGP), a multicenter collaborative effort to collect detailed phenotypic data and DNA on a large number of individuals with epilepsy, including a cohort with symptomatic epilepsy related to PVNH. Included subjects had epilepsy, and MRI confirmed bilateral PVNH. Magnetic resonance imaging studies were visually and quantitatively reviewed to investigate the topographic extent of PVNH, symmetry, and laterality. KEY FINDINGS: We analyzed data on 71 patients with bilateral PVNH. The incidence of febrile seizures was 16.6%. There was at least one other family member with epilepsy in 36.9% of this population. Developmental delay was present in 21.8%. Focal onset seizures were the most common type of seizure presentation (79.3%). High heterotopia burden was strongly associated with female gender and trigonal nodular localization. There was no evidence for differences in brain volume between PVNH subjects and controls. No relationship was observed between heterotopic volume and gender, developmental delay, location of PVNH, ventricular or cerebellar abnormalities, laterality of seizure onset, age at seizure onset, and duration of epilepsy. SIGNIFICANCE: A direct correlation was observed between high heterotopia burden, female gender, and trigonal location in this large cohort of FLNA-negative bilateral PVNH patients with epilepsy. Quantitative MRI measurements indicated that this correlation is based on the diffuse nature of the heterotopic nodules rather than on the total volume of abnormal heterotopic tissue.


Assuntos
Epilepsia/genética , Filaminas/genética , Heterotopia Nodular Periventricular/genética , Adolescente , Adulto , Idade de Início , Encéfalo/patologia , Criança , Pré-Escolar , Estudos de Coortes , Deficiências do Desenvolvimento/patologia , Epilepsia/complicações , Epilepsia/patologia , Feminino , Febre/epidemiologia , Febre/etiologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Heterotopia Nodular Periventricular/complicações , Heterotopia Nodular Periventricular/patologia , Convulsões/epidemiologia , Convulsões/etiologia , Caracteres Sexuais , Adulto Jovem
3.
Acc Chem Res ; 46(1): 116-28, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23110511

RESUMO

The development of high-performance electrochemical energy storage and conversion devices, including supercapacitors, lithium-ion batteries, and fuel cells, is an important step on the road to alternative energy technologies. Carbon-containing nanomaterials (CCNMs), defined here as pure carbon materials and carbon/metal (oxide, hydroxide) hybrids with structural features on the nanometer scale, show potential application in such devices. Because of their pronounced electrochemical activity, high chemical and thermal stability and low cost, researchers are interested in CCNMs to serve as electrodes in energy-related devices. Various all-carbon materials are candidates for electrochemical energy storage and conversion devices. Furthermore, carbon-based hybrid materials, which consist of a carbon component with metal oxide- or metal hydroxide-based nanostructures, offer the opportunity to combine the attractive properties of these two components and tune the behavior of the resulting materials. As such, the design and synthesis of CCNMs provide an attractive route for the construction of high-performance electrode materials. Studies in these areas have revealed that both the composition and the fabrication protocol employed in preparing CCNMs influence the morphology and microstructure of the resulting material and its electrochemical performance. Consequently, researchers have developed several synthesis strategies, including hard-templated, soft-templated, and template-free synthesis of CCNMs. In this Account, we focus on recent advances in the controlled synthesis of such CCNMs and the potential of the resulting materials for energy storage or conversion applications. The Account is divided into four major categories based on the carbon precursor employed in the synthesis: low molecular weight organic or organometallic molecules, hyperbranched or cross-linked polymers consisting of aromatic subunits, self-assembling discotic molecules, and graphenes. In each case, we highlight representative examples of CCNMs with both new nanostructures and electrochemical performance suitable for energy storage or conversion applications. In addition, this Account provides an overall perspective on the current state of efforts aimed at the controlled synthesis of CCNMs and identifies some of the remaining challenges.

4.
Headache ; 53(1): 104-117, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23078588

RESUMO

OBJECTIVE: To evaluate the safety/tolerability of rizatriptan in the long-term acute treatment of migraine in pediatric patients. BACKGROUND: Acute migraine treatment options for children are limited. A recent single-attack trial demonstrated that rizatriptan is effective in eliminating migraine headache pain in this population. We evaluated the long-term safety and efficacy of rizatriptan when used for intermittent acute treatment. METHODS: Open-label study in pediatric migraineurs ages 12-17 years. Patients weighing <40 kg received rizatriptan (orally disintegrating tablet) 5 mg, and those weighing ≥40 kg received 10 mg. Patients could treat up to 8 mild/moderate/severe migraine attacks per month for up to 12 months. One dose of study medication was allowed in a 24-hour period. RESULTS: A total of 674 patients were enrolled, and 606 patients were treated with study medication (N = 583 for 10 mg, N = 23 for 5 mg). The mean duration in the study was 292 days, and the mean number of doses of study medication taken was 20. Over the course of the study within 14 days post-any-dose, 66.0% (400) of the 606 treated patients had any adverse event, 2.3% (14) discontinued due to an adverse event, 2.6% (16) had a serious adverse event, and 23.4% (142) had a triptan-related adverse event. Of the 16 patients with serious adverse events within 14 days post-any-dose, the adverse events in 3 were considered drug-related; all 3 patient's adverse events were classified as serious only because they were associated with an overdose (use of >1 dose of study medication in a 24-hour period). The mean percentage of patient's attacks with pain freedom at 2-hours post-dose was 46.3%; this was relatively consistent over time (Months 1-3 = 43.7%, Months 4-6 = 51.9%, Months 7-9 = 49.9%, Months 10-12 = 49.5%). CONCLUSION: Rizatriptan was generally safe and well tolerated in the long-term acute treatment of migraine in pediatric patients aged 12-17 years and demonstrated a consistent treatment effect over time.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Agonistas do Receptor de Serotonina/uso terapêutico , Triazóis/uso terapêutico , Triptaminas/uso terapêutico , Adolescente , Criança , Feminino , Humanos , Masculino , Agonistas do Receptor de Serotonina/efeitos adversos , Triazóis/efeitos adversos , Triptaminas/efeitos adversos
5.
Langmuir ; 28(1): 27-30, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22142229

RESUMO

A twin-tailed glutamate-based lipid with a pyridine headgroup was prepared in good yield using standard amide coupling and protection/deprotection chemistry. The resulting Lewis basic lipid gels a wide array of hydrocarbon solvents at a critical gelation concentration (C(g)) of 0.3 wt %. The gelation of more polar solvents, such as ethanol, THF, dichloromethane, and chloroform, occurs with a C(g) of between 2 and 5 wt %, demonstrating the importance of hydrogen bonding interactions in gel formation. The importance of hydrogen bonding in this system was also demonstrated by IR observation of the amide bands, which show a substantial shift upon gelation. Solutions of this new organogelator with concentrations below C(g) rapidly form gels upon the introduction of a wide variety of metal salts or complexes, providing a convenient general method for the preparation of metallogelators. Spectroscopic evidence suggests that the enhanced gelation seen in the metal-containing systems can be explained by a cross-linking of gel fibril aggregates similar to those formed by the unmetalated gelator.


Assuntos
Géis , Ácido Glutâmico/química , Lipídeos/química , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Peso Molecular , Espectrofotometria Infravermelho
6.
Cephalalgia ; 32(10): 750-65, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22711898

RESUMO

BACKGROUND: Treatment options for children and adolescents with migraine are limited. This study evaluated rizatriptan for the acute treatment of migraine in children and adolescents. METHODS: Randomized, double-blind, placebo-controlled, parallel-group trial in migraineurs 6-17 years old with unsatisfactory response to nonsteroidal anti-inflammatory drugs or acetaminophen/paracetamol. The trial included a double-blind run-in with weight-based rizatriptan dosing (5 mg for < 40 kg, 10 mg for ≥ 40 kg). In the Stage 1 run-in, patients were randomized in a ratio of 20:1 placebo:rizatriptan and were instructed to treat within 30 minutes of a moderate/severe migraine. Patients with mild/no pain after 15 minutes of treatment (responders) took no further study medication, whereas patients with moderate/severe pain (non-responders) proceeded to take study medication in Stage 2. Non-responders who received placebo in Stage 1 were randomized 1:1 to rizatriptan:placebo, whereas non-responders who received rizatriptan in Stage 1 were allocated to placebo in Stage 2. The primary efficacy endpoint was pain freedom at 2 hours after Stage 2 dose in 12-17-year-olds. RESULTS: A higher proportion of 12-17-year-olds on rizatriptan had pain freedom at 2 hours compared with those on placebo: 87/284 (30.6%) versus 63/286 (22.0%), odds ratio = 1.55 [95% CI: 1.06 to 2.26], p = 0.025. Adverse events within 14 days of dose in 12-17-year-olds were similar for rizatriptan and placebo. The pattern of findings was similar in 6-17-year-olds. CONCLUSION: Rizatriptan demonstrated a statistically significant improvement over placebo in eliminating pain and was generally well tolerated in migraineurs aged 12-17 and 6-17 years. TRIAL REGISTRATION: ClinicalTrials.gov NCT01001234.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Agonistas do Receptor de Serotonina/uso terapêutico , Triazóis/uso terapêutico , Triptaminas/uso terapêutico , Adolescente , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
Cephalalgia ; 31(6): 712-22, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21383045

RESUMO

BACKGROUND: This study evaluated the CGRP receptor antagonist MK-3207 for acute treatment of migraine. METHODS: Multicenter, double-blind, randomized, placebo-controlled, parallel-group, two-stage adaptive study with two interim efficacy analyses to facilitate optimal dose selection. Migraine patients were initially randomized to MK-3207 2.5, 5, 10, 20, 50 and 100 mg or placebo to treat a moderate/severe migraine. One or more doses were to be discontinued based on the first interim analysis and a lower or higher dose could be added based on the second interim analysis. The primary endpoint was two-hour pain freedom. RESULTS: A total of 547 patients took study medication. After the first interim analysis, the two lowest MK-3207 doses (2.5, 5 mg) were identified as showing insufficient efficacy. Per the pre-specified adaptive design decision rule, only the 2.5-mg group was discontinued and the five highest doses (5, 10, 20, 50, 100 mg) were continued into the second stage. After the second interim efficacy analysis, a 200 mg dose was added due to insufficient efficacy at the top three (20, 50, 100 mg) doses. A positive dose-response trend was demonstrated when data were combined across all MK-3207 doses for two-hour pain freedom (p < .001). The pairwise difference versus placebo for two-hour pain freedom was significant for 200 mg (p < .001) and nominally significant for 100 mg and 10 mg (p < .05). The incidence of adverse events appeared comparable between active treatment groups and placebo, and did not appear to increase with increasing dose. CONCLUSIONS: MK-3207 was effective and generally well tolerated in the acute treatment of migraine.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Transtornos de Enxaqueca/tratamento farmacológico , Compostos de Espiro/administração & dosagem , Doença Aguda , Adulto , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Índice de Gravidade de Doença , Compostos de Espiro/efeitos adversos , Resultado do Tratamento
8.
PLoS One ; 15(7): e0235667, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730271

RESUMO

Botswana's Okavango Delta is a World Heritage Site and biodiverse wilderness. In 2016-2018, following arrival of the annual flood of rainwater from Angola's highlands, and using continuous oxygen logging, we documented profound aquatic hypoxia that persisted for 3.5 to 5 months in the river channel. Within these periods, dissolved oxygen rarely exceeded 3 mg/L and dropped below 0.5 mg/L for up to two weeks at a time. Although these dissolved oxygen levels are low enough to qualify parts of the Delta as a dead zone, the region is a biodiversity hotspot, raising the question of how fish survive. In association with the hypoxia, histological samples, collected from native Oreochromis andersonii (threespot tilapia), Coptodon rendalli (redbreast tilapia), and Oreochromis macrochir (greenhead tilapia), exhibited widespread hepatic and splenic inflammation with marked granulocyte infiltration, melanomacrophage aggregates, and ceroid and hemosiderin accumulations. It is likely that direct tissue hypoxia and polycythemia-related iron deposition caused this pathology. We propose that Okavango cichlids respond to extended natural hypoxia by increasing erythrocyte production, but with significant health costs. Our findings highlight seasonal hypoxia as an important recurring stressor, which may limit fishery resilience in the Okavango as concurrent human impacts rise. Moreover, they illustrate how fish might respond to hypoxia elsewhere in the world, where dead zones are becoming more common.


Assuntos
Oxigênio/química , Tilápia/metabolismo , Animais , Ceroide/metabolismo , Eritrócitos/citologia , Eritrócitos/metabolismo , Feminino , Hemossiderina/metabolismo , Hipóxia , Ferro/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Oxigênio/metabolismo , Rios , Baço/metabolismo , Baço/patologia
9.
J Am Chem Soc ; 130(43): 14303-10, 2008 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-18826311

RESUMO

Reaction of HAuCl4 x 3 H2O with excess HSAr (Ar = C6F5 or C6F4H) in ethanol, followed by addition of [Et4N]Cl, produced [Et4N][Au(SAr)4] (Ar = C6F5 (1a) or C6F4H (1b)) as red crystalline solids in high yield. These complexes are rare examples of homoleptic gold(III) thiolate complexes. The crystal structures 1 show square planar geometry at the gold center with elongated Au-S bonds. Both complexes undergo reversible reductive elimination/oxidative addition processes in solution via thermal and photochemical pathways. Equilibrium constant and photostationary state measurements indicate that the relative importance of the two pathways depends on the nature of the aromatic groups. The metal-containing reductive elimination products, [Et4N][Au(SAr)2] (Ar = C6F5 (2a) or C6F4H (2b)), were confirmed by both independent synthesis and crystallographic characterization. Cross-reactions between either 1 or 2 and various disulfides led to ligand exchange via an addition-elimination process, a previously unknown reaction pathway for ligand exchange at gold(I) centers.

10.
Lung Cancer ; 125: 273-281, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30429032

RESUMO

OBJECTIVES: Platinum-based chemotherapy for advanced non-small-cell lung cancer (NSCLC) has modest benefit overall, but has the potential to amplify immune responses. In cohorts A-C of the multicohort phase 1/2 study KEYNOTE-021 (Clinicaltrials.gov, NCT02039674), we evaluated combinations of platinum-doublet chemotherapy with the anti-programmed death 1 monocloncal antibody pembrolizumab. MATERIALS AND METHODS: Patients with previously untreated, advanced NSCLC without EGFR/ALK aberrations were randomized to pembrolizumab 2 or 10 mg/kg Q3W plus carboplatin area under the serum concentration-time curve (AUC) 6 mg/mL/min plus paclitaxel 200 mg/m2 (cohort A, any histology), carboplatin AUC 6 mg/mL/min plus paclitaxel 200 mg/m2 plus bevacizumab 15 mg/kg (cohort B, non-squamous), or carboplatin AUC 5 mg/mL/min plus pemetrexed 500 mg/m2 (cohort C, non-squamous) for 4 cycles followed by maintenance pembrolizumab (cohort A), pembrolizumab plus bevacizumab (cohort B), or pembrolizumab plus pemetrexed (cohort C). Response was assessed by blinded independent central review. RESULTS: Overall, 74 patients were randomized; median follow-up was 21.4, 16.4, and 17.4 months in cohorts A, B, and C, respectively. No dose-limiting toxicities occurred in any cohort at either pembrolizumab dose. Most frequent treatment-related adverse events (AEs) were alopecia, fatigue, and nausea. Treatment-related grade 3/4 AEs occurred in 40%, 42%, and 46% of patients in cohorts A, B, and C, respectively; AEs with possible immune etiology occurred in 24%, 50%, and 38% of patients, respectively. Objective response rates were 48%, 56%, and 75% in cohorts A, B, and C, respectively. CONCLUSION: Pembrolizumab in combination with carboplatin-paclitaxel and with pemetrexed-carboplatin yielded encouraging antitumor activity and toxicity consistent with known toxicities of platinum-based chemotherapy or pembrolizumab monotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab/administração & dosagem , Carboplatina/administração & dosagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Paclitaxel/administração & dosagem , Pemetrexede/administração & dosagem
11.
Inorg Chem ; 37(21): 5657-5663, 1998 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11670715

RESUMO

Reaction of AgBF(4) with 2 equiv of Ph(3)P in acetonitrile followed by recrystallization from dichloromethane/hexane yields the mixed phosphine-nitrile complex [(Ph(3)P)(2)AgNCCH(3)]BF(4) (I) as its dichloromethane solvate, I.0.5CH(2)Cl(2). This solvate crystallizes in the monoclinic space group C2/c with a = 22.928(5), b = 12.700(3), c = 25.156(5) Å, beta = 97.53(3) degrees, and Z = 8. The acetonitrile ligand in I is loosely bound to the metal center and easily lost, even in the solid state, without decomposition. Hence, recrystallization of dried samples of I.0.5CH(2)Cl(2) from CH(2)Cl(2)/hexane results in isolation of the novel low-coordinate phosphine complex [(Ph(3)P)(2)Ag]BF(4) (II). II crystallizes in the monoclinic space group C2/c with a = 21.733(9), b = 12.272(4), c = 24.356(9) Å, beta = 95.01(3) degrees, and Z = 8. In both cases, a weak interaction is present between a fluorine atom of the BF(4)(-) anion and the silver cation. However, these interactions appear to be essentially electrostatic rather than dative in nature, implying that I is best considered a three-coordinate silver complex and that II is a rare, structurally characterized example of a two-coordinate silver-phosphine complex. These solid-state geometric assignments are supported by (31)P NMR studies, which reveal a Ag-P coupling constant of 550 Hz for II, consistent with the presence of a linear two-coordinate complex in solution. The NMR data also indicate that the phosphine ligands are involved in exchange processes, which are accelerated by the presence of a donor solvent such as acetonitrile. Comparison of II with its gold analogue supports the previously stated concept that gold atoms are smaller than silver atoms. An analysis of 13 other isostructural pairs of silver and gold complexes culled from the crystallographic database lends further support to this concept.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA