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1.
J Am Chem Soc ; 131(28): 9746-55, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-19555102

RESUMO

The rates of catalytic oxidative decontamination of the chemical warfare agent (CWA) sulfur mustard (HD, bis(2-chlororethyl) sulfide) and a range (chloroethyl) sulfide simulants of variable lipophilicity have been examined using a hydrogen peroxide-based microemulsion system. SANS (small-angle neutron scattering), SAXS (small-angle X-ray scattering), PGSE-NMR (pulsed-gradient spin-echo NMR), fluorescence quenching, and electrospray mass spectroscopy (ESI-MS) were implemented to examine the distribution of HD, its simulants, and their oxidation/hydrolysis products in a model oil-in-water microemulsion. These measurements not only present a means of interpreting decontamination rates but also a rationale for the design of oxidation catalysts for these toxic materials. Here we show that by localizing manganese-Schiff base catalysts at the oil droplet-water interface or within the droplet core, a range of (chloroethyl) sulfides, including HD, spanning some 7 orders of octanol-water partition coefficient (K(ow)), may be oxidized with equal efficacy using dilute (5 wt. % of aqueous phase) hydrogen peroxide as a noncorrosive, environmentally benign oxidant (e.g., t(1/2) (HD) approximately 18 s, (2-chloroethyl phenyl sulfide, C(6)H(5)SCH(2)CH(2)Cl) approximately 15 s, (thiodiglycol, S(CH(2)CH(2)OH)(2)) approximately 19 s {20 degrees C}). Our observations demonstrate that by programming catalyst lipophilicity to colocalize catalyst and substrate, the inherent compartmentalization of the microemulsion can be exploited to achieve enhanced rates of reaction or to exert control over product selectivity. A combination of SANS, ESI-MS and fluorescence quenching measurements indicate that the enhanced catalytic activity is due to the locus of the catalyst and not a result of partial hydrolysis of the substrate.


Assuntos
Substâncias para a Guerra Química/química , Descontaminação/métodos , Gás de Mostarda/química , Catálise , Substâncias para a Guerra Química/isolamento & purificação , Emulsões , Cinética , Espectroscopia de Ressonância Magnética , Gás de Mostarda/isolamento & purificação , Difração de Nêutrons , Óleos/química , Oxirredução , Espalhamento a Baixo Ângulo , Solubilidade , Propriedades de Superfície , Água/química
2.
Am Surg ; 73(11): 1117-21, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18092644

RESUMO

Tracheostomy is associated with increased aspiration rates, and swallowing disorders have not been well-studied in trauma patients with tracheostomy. Swallowing evaluations were conducted in 224 patients (102 trauma and 122 nontrauma patients). Half of the patients in each group had tracheostomies. Bedside swallow studies were conducted in 40 patients, videofluoroscopy swallow studies in 100 patients, and both studies in 84 patients. chi2, Fisher's exact test, Cramer's V, and descriptive statistics were used for data analysis. Aspiration occurred in 35 per cent (36 of 102) of trauma patients with or without tracheostomy and in 36 per cent (22 of 61) of nontrauma patients with tracheostomy. Aspiration with and without penetration was observed in 54 per cent of trauma patients (55% with tracheostomy) compared with 67 per cent of all nontrauma patients (61% with tracheostomy). Trauma patients with head injuries exhibited 41 per cent (26 of 63) aspiration and 68 per cent (43 of 63) dysphagia compared with 26 per cent (10 of 39) and 59 per cent (23 of 39) in trauma patients with other injuries. There was a lower incidence of dysphagia in trauma patients (65% versus 81% in nontrauma) and in patients with tracheostomy (71% versus 77% without tracheostomy). Tracheostomy was not associated with increased dysphagia or aspiration.


Assuntos
Traumatismos Craniocerebrais/terapia , Transtornos de Deglutição/etiologia , Traumatismos da Medula Espinal/terapia , Traqueostomia/efeitos adversos , Traumatismos Craniocerebrais/diagnóstico por imagem , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/epidemiologia , Fluoroscopia , Seguimentos , Humanos , Incidência , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Traumatismos da Medula Espinal/diagnóstico por imagem , Índices de Gravidade do Trauma
3.
Am Surg ; 73(11): 1173-80, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18092658

RESUMO

Serial venous duplex scans (VDS) were done in 507 trauma patients with at least one risk factor (RF) for venous thromboembolism (VTE) during a 2-year study period. Deep vein thrombosis (DVT) was detected in 31 (6.1%) patients. This incidence was 3.1 per cent in low (1-2 RFs), 3.4 per cent in moderate (3-5 RFs), and 7.7 per cent in high (> or =6 RFs) VTE scores (P = 0.172). Incidence was statistically different (3% vs. 7.2%, P = 0.048) on reanalyzing patients in two risk categories, low-risk (1-4 RFs) and high-risk (> or =5 RFs). Only 4 of 16 RFs had statistically higher incidence of DVT in patients with or without RFs: previous VTE (27.3% vs. 5.6%, odds ratio (OR) 6.628, P = 0.024), spinal cord injury (22.6% vs. 5%, OR 5.493, P = 0.001), pelvic fractures (11.4% vs. 5.1%, OR 2.373, P = 0.042), and head injury with a greater than two Abbreviated Injury Score (10.5% vs. 4.2%, OR 2.639, P = 0.014). On reanalyzing patients with > or =5 RFs vs. <5RFs, obesity (14.3 vs. 6.1%, P = 0.007), malignancy (5.6% vs. 0.6%, P = 0.006), coagulopathy (10.8% vs. 1.8%, P = 0.000), and previous VTE (3.2% vs. 0%, P = 0.019) were significant on univariate analysis. Patients with DVT had 3.70 +/- 1.75 RFs and a 9.61 +/- 4.93 VTE score, whereas, patients without DVT had 2.66 +/- 1.50 RFs and a 6.83 +/- 3.91 VTE score (P = 0.000). DVTs had a direct positive relationship with higher VTE scores, length of stay, and number of VDS (>1 r, P < or = 0.001). Increasing age was a weak risk factor (0.03 r, P = 0.5). First two VDS diagnosed 77 per cent of DVTs. Patients with injury severity score of > or =15 and 25 had higher DVTs compared with the ones with lower injury severity score levels (P < or = 0.05). Pulmonary embolism was silent in 63 per cent and DVTs were asymptomatic in 68 per cent.


Assuntos
Traumatismo Múltiplo/complicações , Tromboembolia Venosa/etiologia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/diagnóstico , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Índices de Gravidade do Trauma , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia
4.
Int J Pharm ; 338(1-2): 207-12, 2007 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17363199

RESUMO

The complexation of EPA with ketoprofen was probed in order to rationalise co-operative skin permeation enhancement behaviour observed previously. The modulation of aromatic protons of ketoprofen was determined using (1)H NMR spectra from different formulations containing varying concentrations of fish oil and a control saturated triglyceride. Molecular modelling of possible complexes of ketoprofen with constituents of fish oil was performed. NMR data revealed a dose-dependent change in chemical shift in the aromatic protons of ketoprofen on addition of fish oil and/or EPA. Similar patterns were observed in both cases, although the free fatty acid induced changes in more protons. Molecular modelling results indicate quite large binding energies of all complexes considered, varying between ca. 90 and 160 kJ mol(-1). The geometries of these complexes shows strong O-H...O hydrogen bonds in all cases, and in the case of the complex of ketoprofen with free EPA there is also some evidence of C-H... pi and/or pi-pi interactions, giving rise to regiospecifically solvated complexes. If strongly bound ketoprofen:EPA complexes can form, then the permeation enhancement of EPA by ketoprofen could be attributed to such a complex. Once the complex is formed, the triglyceride/free fatty acid could aid permeation of associated ketoprofen into the lipophilic stratum corneum via the pull effect. Once permeated, the more hydrophilic ketoprofen could aid the permeation of the triglyceride/free fatty acid through the epidermis, again via the pull effect. This could explain the synergistic permeation enhancement seen with these compounds.


Assuntos
Ácido Eicosapentaenoico/química , Cetoprofeno/administração & dosagem , Cetoprofeno/química , Modelos Moleculares , Absorção Cutânea , Química Farmacêutica , Cetoprofeno/farmacocinética , Espectroscopia de Ressonância Magnética
5.
Am J Prev Med ; 30(4): 305-312, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16530617

RESUMO

BACKGROUND: This national study assessed police chiefs' support for various types of firearm control measures, perceptions regarding firearms as a public health problem, and the likelihood of initiating firearm control advocacy activities. METHODS: A 29-item survey instrument was developed to assess respondents' likelihood of firearm policy support, interest, exposure, involvement with firearm control advocacy, and demographic and background characteristics. The survey was sent out in spring 2005 using a three-wave mailing to a national random sample of 600 police chiefs in cities with populations greater than 25,000 in 2002 and 2003. RESULTS: The majority of responding police chiefs supported 11 out of 14 proposed firearm control policies. Most police chiefs (62%) believed that the government should do everything it can to keep handguns out of the hands of criminals, even if it makes it more difficult for law-abiding citizens to purchase handguns. Police chiefs were not likely to participate in the majority of firearm control advocacy activities. The advocacy activities that police chiefs were most likely to participate in were meeting with state legislators (52%) and writing a letter to a legislator in relation to gun control (44%). CONCLUSIONS: Police chiefs support several potentially important firearm control policies. This suggests the need to evaluate interventions aimed at increasing their role in shaping policy on this important public health issue.


Assuntos
Atitude , Armas de Fogo/legislação & jurisprudência , Propriedade/legislação & jurisprudência , Polícia , Percepção Social , Defesa do Consumidor , Feminino , Humanos , Masculino , Saúde Pública , Ferimentos por Arma de Fogo/prevenção & controle
6.
Ann Clin Lab Sci ; 32(4): 363-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12458887

RESUMO

An educational program for cancer patients is reported that focuses specifically on the interpretation of their surgical pathology reports. In this program, features of the surgical pathology report that are important to an understanding of the biology, prognosis, and therapy of the different forms of cancer are explained to the patients. Individual interaction of each patient with an experienced surgical pathologist, who serves as the program moderator, permits frank discussion about aspects of cancer diagnosis that are of particular interest to these patients, but that are not routinely addressed during their disease management. Opportunities are provided for periodic follow-up with the moderator in order to address any additional questions or concerns that arise regarding subsequent surgical pathology reports.


Assuntos
Prontuários Médicos , Neoplasias/patologia , Neoplasias/cirurgia , Patologia Clínica/métodos , Educação de Pacientes como Assunto/métodos , Humanos , Neoplasias/terapia , Relações Médico-Paciente , Prognóstico
8.
Adv Colloid Interface Sci ; 144(1-2): 13-23, 2008 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-18812239

RESUMO

Incorporation of d- or f-block metals into ligand systems that renders a metal complex surface-active or drives its partitioning into surfactant phases enables the localisation of chemical functionality at interfaces. This article discusses a number of fundamental aspects of these interesting materials and examines potential applications.


Assuntos
Metais/química , Micelas , Elementos de Transição/química , Ésteres/química , Hidrólise , Íons , Estrutura Molecular , Nitrofenóis/química , Fosfatos/química , Ácidos Picolínicos/química , Bases de Schiff/química , Soluções , Tensoativos/química , Água
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