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1.
Stroke ; 47(3): 682-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26814235

RESUMO

BACKGROUND AND PURPOSE: We aimed to determine associations of baseline blood glucose and diabetes mellitus with clinical outcomes in participants of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2). METHODS: INTERACT2 was an international prospective, open, blinded end point, randomized controlled trial of 2839 patients with spontaneous intracerebral hemorrhage (<6 hours) and elevated systolic blood pressure randomly assigned to intensive (target systolic blood pressure <140 mm Hg) or guideline-based (systolic blood pressure <180 mm Hg) BP management. Associations of hyperglycemia at presentation (>6.5 mmol/L) and combined and separate poor outcomes of death and major disability (scores of 3-6, 3-5, and 6, respectively, on the modified Rankin scale) at 90 days were determined in logistic regression models. RESULTS: In 2653 patients with available data, there were 1348 (61%) with hyperglycemia and 292 (11%) with diabetes mellitus. Associations of baseline blood glucose and poor outcome were strong and near continuous. After adjustment for baseline variables, the highest fourth (7.9-25.0 mmol/L) of blood glucose was significantly associated with combined poor outcome (adjusted odds ratio 1.35, 95% confidence interval 1.01-1.80; P trend 0.015). Diabetes mellitus also predicted poor outcome (adjusted odds ratio 1.46, 95% confidence interval 1.05-2.02; P=0.023), though more important for residual disability than death on separate analysis. CONCLUSIONS: Hyperglycemia and diabetes mellitus are independent predictors of poor outcome in patients with predominantly mild to moderate severity of intracerebral hemorrhage. These data support guideline recommendations for good glycemic control in patients with intracerebral hemorrhage. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00716079.


Assuntos
Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/epidemiologia , Hiperglicemia/diagnóstico , Hiperglicemia/epidemiologia , Internacionalidade , Doença Aguda , Idoso , Glicemia/metabolismo , Hemorragia Cerebral/sangue , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hiperglicemia/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Método Simples-Cego
2.
Stroke ; 46(3): 653-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25677598

RESUMO

BACKGROUND AND PURPOSE: Intraventricular hemorrhage (IVH) with spontaneous intracerebral hemorrhage indicates a poor prognosis but uncertainty exists over the pattern of association. We aimed to elucidate risk associations of IVH and outcome in the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2) data set. METHODS: INTERACT2 was an international prospective, open-blinded end point, randomized controlled trial in 2839 patients with intracerebral hemorrhage (<6 hours) with elevated systolic blood pressure randomly assigned to intensive (target systolic blood pressure <140 mm Hg) or guideline-based (systolic blood pressure <180 mm Hg) blood pressure management. Associations of baseline IVH in 740 of 2613 (28%) patients and poor outcomes (death and major disability defined on the modified Rankin Scale) at 90 days were determined in linear and logistic regression models. RESULTS: Patients with IVH were significantly older and with greater neurological impairment, history of ischemic stroke, and larger hematomas more often deep hemisphere located at presentation, after adjustment for other baseline variables. Death or major disability occurred in 66% with IVH versus 49% in intracerebral hemorrhage-alone patients (adjusted odds ratio, 1.68; 95% confidence interval, 1.38-2.06; P<0.01). Associations of IVH volume and clinical outcomes were strong and near continuous. Adjusted analyses by thirds of IVH volume indicate thresholds of ≈5 and 10 mL for significantly increased odds of death and death or major disability, respectively. CONCLUSIONS: A strong association exists between the amount of IVH and poor outcome in intracerebral hemorrhage. An IVH volume of 5 to 10 mL emerges as a significant threshold for decision making on prognosis in these patients. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00716079.


Assuntos
Neoplasias Encefálicas/patologia , Hemorragia Cerebral/patologia , Doença Aguda , Idoso , Pressão Sanguínea , Bases de Dados Factuais , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Análise de Regressão , Sístole , Tomografia Computadorizada por Raios X , Resultado do Tratamento
3.
J Nanosci Nanotechnol ; 12(12): 8975-84, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23447947

RESUMO

The present work deals with the preparation and characterization of silane grafted MMT (S-MMT), organomodified MMT (O-MMT) and silane grafted organomodified montmorillonite (OS-MMT) reinforced silicone rubber (SR) nanocomposites. XRD of SR filled with O-MMT (1-8 wt%), OS-MMT (1-8 wt%) and S-MMT (1-5 wt%) suggested the formation exfoliated morphology, which has also been supported by the corresponding TEM images of 3 wt% filled SR nanocomposites. TGA and DSC studies of SR/OS-MMT (3 wt%) nanocomposites have shown that the thermal stability, glass transition temperature and crystallization temperature are maximum improved with respect to neat SR by 50, 14 and 10 degrees C respectively. This is attributed to the synergistic effect of organo-modification followed by amino silane grafting of MMT on thermal properties of SR. The tensile strength of SR/S-MMT (5 wt%), SR/O-MMT (3 wt%) and SR/OS-MMT (3 wt%) relatively improved by 134, 312, and 259% respectively suggesting that the synergistic effect of OS-MMT is not effective in reinforcing the mechanical properties of SR. In all probability, the curing of SR through hydrosilylation is inhibited by the lone pair on nitrogen in NH2 group of OS-MMT.

4.
ACS Omega ; 7(5): 3844-3859, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35155882

RESUMO

Nanofillers (NFs) are becoming a ubiquitous choice for applications in different technological innovations in various fields, from biomedical devices to automotive product portfolios. Potential physical attributes like large surface areas, high surface energy, and lower structural imperfections make NFs a popular filler over microfillers. One specific application, where NFs are finding applications, is in adhesive science and technology. Incorporating NFs in the adhesive matrix is seen to tune the adhesives' different properties like wettability, rheology, etc. Additionally, the functional benefits (like electrical/thermal conductivity) of these NFs are translated into the adhesives' properties. Such an improvement in the properties is far to achieve using microfillers in the adhesive matrix. This mini-review provides an account of the impact of the addition of various nanofillers (NFs) on the properties of the adhesive composition.

5.
ACS Omega ; 5(35): 22482-22493, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923807

RESUMO

Polydimethylsiloxane (PDMS) polymers are highly appreciated materials that are broadly applied in several industries, from baby bottle nipples to rockets. Momentive researchers are continuously working to understand and expand the scope of PDMS-based materials. Fluorofunctional PDMS has helped the world to apply in specialty applications. Efforts are taken to develop such siloxane-fluoropolymer composite materials with good thermal, solvent, and chemical resistance performances. We leveraged inherently flexible PDMS as the model matrix, whereas polytetrafluoroethylene (PTFE) was used as the additive to impart the functional benefits, offering great value in comparison to the individual polymers. The composites were made at three different mixing temperatures, that is, 0-35 °C, and different loadings of PTFE, that is, 0.5-8% (w/w), were selected as the model condition. A strong dependency of the mixing temperature against the performance attributes of the developed composites was noted. Mechanical and thermal stability of the composites were evaluated along with optical properties. X-ray diffraction demonstrated the change in the crystallite size of the PTFE particles as a function of processing temperature. Compared to the phase II crystallite structure of the PTFE, the fibrils formed in phase IV imparted a better reinforcing capability toward the PDMS matrix. A synergistic balance between higher filler loading and mechanical properties of the composite can be achieved by doping the formulation with short-chain curable PDMS, with 238% increment of tensile strength at 8 wt % PTFE loading when compared to the control sample. The learning was extended to check the applicability of doping such PTFE powder in commercial liquid silicone rubber (LSR). In the window of study, the formulated LSR demonstrated improved mechanical properties with additional functional benefits like resistance toward engine oil and other chemical solvents.

6.
Stroke Vasc Neurol ; 3(1): 22-27, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29600004

RESUMO

The benefits and safety of intravenous recombinant tissue plasminogen activator (IV-tPA) for patients with mild ischaemic stroke (MIS) are still unclear. The objective of this meta-analysis was to evaluate the efficacy and safety of IV-tPA as treatment for patients with MIS. We performed a systematic literature search across MEDLINE, Embase, Central, Global Health and Cumulative Index to Nursing and Allied Health Literature (CINAHL), from inception to 10 November 2016, to identify all related studies. Where possible, data were pooled for meta-analysis with odds ratio (OR) and corresponding 95% confidence interval (CI) using the fixed-effects model. MIS was defined as having National Institutes of Health Stroke Scale score of ≤6. We included seven studies with a total of 1591 patients based on the prespecified inclusion and exclusion criteria. The meta-analysis indicated a high odds of excellent functional outcome based on the modified Rankin Scale or Oxfordshire Handicap Score 0-1 (OR=1.43; 95% CI 1.14 to 1.79; P=0.002, I2=35%) in patients treated with IV-tPA compared with those not treated with IV-tPA (74.8% vs 67.6%). There was a high risk of symptomatic intracranial haemorrhage (sICH) with IV-tPA treatment (OR=10.13; 95% CI 1.93 to 53.02; P=0.006, I2=0%) (1.9% vs 0.0%) but not mortality (OR=0.78; 95% CI 0.43 to 1.43; P=0.43, I2=0%) (2.4% vs 2.9%). Treatment with IV-tPA was associated with better functional outcome but not mortality among patients with MIS, although there was an increased risk of sICH. Randomised trials are warranted to confirm these findings.


Assuntos
Fibrinolíticos/administração & dosagem , AVC Isquêmico/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/efeitos adversos , Estado Funcional , Humanos , Infusões Intravenosas , Hemorragias Intracranianas/induzido quimicamente , AVC Isquêmico/diagnóstico , AVC Isquêmico/mortalidade , AVC Isquêmico/fisiopatologia , Masculino , Proteínas Recombinantes/administração & dosagem , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/mortalidade , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
7.
Chem Commun (Camb) ; (25): 2705-7, 2006 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-16786094

RESUMO

Unique conformations such as rod, semicircle, and circle structures of isolated semi-flexible helical polysilanes were observed by atomic force microscopy (AFM); the chain topology was significantly related to the chain length (molecular weight) on the surfaces.

8.
Cerebrovasc Dis Extra ; 6(3): 71-75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27603933

RESUMO

BACKGROUND: Intraventricular hemorrhage (IVH) extension is common following acute intracerebral hemorrhage (ICH) and is associated with poor prognosis. AIM: To determine whether intensive blood pressure (BP)-lowering therapy reduces IVH growth. METHODS: Pooled analyses of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trials (INTERACT1 and INTERACT2) computed tomography (CT) substudies; multicenter, open, controlled, randomized trials of patients with acute spontaneous ICH and elevated systolic BP, randomly assigned to intensive (<140 mm Hg) or guideline-based (<180 mm Hg) BP management. Participants had blinded central analyses of baseline and 24-hour CT. Association of BP lowering to IVH growth was assessed in analysis of covariance. RESULTS: There was no significant difference in adjusted mean IVH growth following intensive (n = 228) compared to guideline-recommended (n = 228) BP treatment (1.6 versus 2.2 ml, respectively; p = 0.56). Adjusted mean IVH growth was nonsignificantly greater in patients with a mean achieved systolic BP ≥160 mm Hg over 24 h (3.94 ml; p trend = 0.26). CONCLUSIONS: Early intensive BP-lowering treatment had no clear effect on IVH in acute ICH.

9.
Chem Commun (Camb) ; (5): 538-9, 2004 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-14973596

RESUMO

Cooperative amplification of the C-F...Si weak interaction between side chains and the main chain was found to afford rigid rodlike helical polysilanes with a preferential screw sense.

11.
Langmuir ; 21(9): 3957-62, 2005 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-15835961

RESUMO

The present paper reports uniqueness of a simple, programmed design of disk-shaped homochiral nickel phthalocyanine (Pc) molecules bearing four enantiomerically pure 1-(p-tolyl)ethylaminocarbonyl groups at their peripheral positions, (Pc-(R) and Pc-(S)), and their controlled self-organization into mesoscopic supramolecular helical fibers with a preferential handedness in solution and onto solid surfaces. A combination of four fundamental intermolecular interactions, including quadruple hydrogen bonding, pi-pi stacking, homochiral interactions of the enantiopure bulky aralkyl entities, and noncoordinating nature of nickel ion of the Pc molecules afforded a high thermal stability of the Pc self-assembly in chloroform (CHCl(3)), tetrahydrofuran, and o-dichlorobenzene and onto hydrophilic mica and hydrophobic HOPG surfaces. A higher-ordered helical self-assembly of Pc disks was observed in these solutions (approximately 200 Pc molecules), while the self-assembly was completely dissociated into monomeric species in N,N-dimethylformamide due to a loss of hydrogen-bonding interactions between Pc molecules. Supramolecular chirality in the hierarchical self-assembly of Pc molecules originated from the presence of (R)- or (S)-chiral centers in the peripheral tails, which rotate noncovalently linked molecular building blocks to effectively form the helical architectures. The helical Pc nanofibers dissolved in CHCl(3), estimated to be ca. 70 nm from peak molecular weight obtained by SEC analysis, acts as a building block for higher-order helical fibers (ca. 1 microm) at single molecular level on the solid surfaces, as demonstrated by the dynamic force mode atomic force microscopy. Regardless of hydrophilic and hydrophobic substrates, the interaction between these Pc molecules and the solid surfaces could not affect the morphology of helical assemblies, indicating a unique robustness of these assemblies.


Assuntos
Biopolímeros/química , Etilaminas/química , Indóis/química , Níquel/química , Clorobenzenos/química , Clorofórmio/química , Dicroísmo Circular , Furanos/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Isoindóis , Microscopia de Força Atômica , Estrutura Molecular , Peso Molecular , Espectrofotometria Ultravioleta , Estereoisomerismo , Temperatura
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