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1.
Phys Chem Chem Phys ; 20(7): 4721-4731, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29379922

RESUMO

The phase behaviour, ionic conductivity, electrochemical stability and diffusion coefficients of mobile components in three organic ionic plastic crystals (OIPCs): triisobutylmethylphosphonium bis(fluorosulphonyl)amide (P1i444FSI), triisobutylmethylphosphonium bis(trifluromethanesulphonyl)amide (P1i444NTf2) and trimethylisobutylphosphonium bis(trifluoromethanesulphonyl)amide (P111i4NTf2) are compared to study the effect of the anions and cations on phase behaviour and dynamics. The FSI-based OIPC shows lower melting point and higher conductivity values most likely because of the higher degree of charge distributions and weaker ion-ion interactions compared to NTf2 anion-based OIPCs. Cyclic voltammetry of electrolytes consisting of these OIPCs with 70 mol% sodium salt incorporated indicates stable sodium plating/stripping behaviour at 70 and 50 °C for all samples. The magnitude of the peak currents, however, are much higher for the FSI-based electrolyte.

2.
Phys Chem Chem Phys ; 17(14): 8706-13, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25820549

RESUMO

Electrolytes of a room temperature ionic liquid (RTIL), trimethyl(isobutyl)phosphonium (P111i4) bis(fluorosulfonyl)imide (FSI) with a wide range of lithium bis(fluorosulfonyl)imide (LiFSI) salt concentrations (up to 3.8 mol kg(-1) of salt in the RTIL) were characterised using a combination of techniques including viscosity, conductivity, differential scanning calorimetry (DSC), electrochemical impedance spectroscopy (EIS), nuclear magnetic resonance (NMR) and cyclic voltammetry (CV). We show that the FSI-based electrolyte containing a high salt concentration (e.g. 1 : 1 salt to IL molar ratio, equivalent to 3.2 mol kg(-1) of LiFSI) displays unusual transport behavior with respect to lithium ion mobility and promising electrochemical behavior, despite an increase in viscosity. These electrolytes could compete with the more traditionally studied nitrogen-based ionic liquids (ILs) in lithium battery applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37970570

RESUMO

Background: There is little evidence describing respiratory disease among 40.5 million small-scale miners worldwide. Objectives: To describe the prevalence and clinical characteristics of adult respiratory inpatients with silicosis and silicotuberculosis in a tertiary hospital in Tanzania that serves a small-scale mining region. Methods: In this retrospective, cross-sectional survey, patient files from admissions between 2010 and 2020 were opportunistically selected and included if a respiratory diagnosis had been made. Results: Of 223 patients with respiratory conditions, 32 (14.3%; 95% confidence interval (CI) 10.0 - 19.6) were diagnosed with silicosis and 17 (7.6%; 95% CI 4.5 - 11.9) with silicotuberculosis. Mining was the most frequent occupation in those with silicosis (n=15/32; 46.9%) and silicotuberculosis (n=15/17; 88.2%). Of those with silicosis or silicotuberculosis, 26/49 (53.1%) were aged <45 years. Conclusion: Our study suggests that silicosis and silicotuberculosis are common among male and female respiratory inpatients with occupational exposure. The study highlights the role of occupational exposures in respiratory disease in developing economies. Study synopsis: What the study adds. This retrospective, cross-sectional survey describes the prevalence of silicosis and silicotuberculosis among adult respiratory inpatients admitted to a tertiary hospital in northern Tanzania. It is the first study to describe the prevalence and characteristics of respiratory inpatients with silicosis and silicotuberculosis in a small-scale mining region of Africa. A high prevalence of silicosis (14.3%) and silicotuberculosis (7.6%) was found. Patients were often aged <45 years, and the majority required oxygen therapy.Implications of the findings. The high prevalence of advanced silicosis and silicotuberculosis in miners presenting at a young age raises concerns about high occupational silica exposures and, importantly, suggests a need for community-based research, which our team is planning to undertake.

4.
Perfusion ; 27(2): 156-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22143091

RESUMO

An 81-year-old woman with recurrent episodes of dizzy spells was found to have a mass in the right atrium on transthoracic echocardiography. The patient underwent successful surgery to excise the mass, which was arising from the anterior leaflet of the tricuspid valve. Histology showed a papillary fibroelastoma. Although management is still controversial when such tumours are found incidentally in asymptomatic patients, surgery may be considered, especially if the tumour is large, due to the high risk of embolism.


Assuntos
Átrios do Coração/cirurgia , Neoplasias Cardíacas/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Valva Tricúspide/cirurgia , Idoso de 80 Anos ou mais , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/patologia , Humanos , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/patologia , Ultrassonografia
6.
Int J Tuberc Lung Dis ; 21(7): 746-752, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28633698

RESUMO

OBJECTIVE: To assess the feasibility of a streamlined strategy for improving tuberculosis (TB) diagnostic evaluation and treatment initiation among patients with presumed TB. DESIGN: Single-arm interventional pilot study at five primary care health centers of a streamlined, SIngle-saMPLE (SIMPLE) TB diagnostic evaluation strategy: 1) examination of two smear results from a single spot sputum specimen using light-emitting diode fluorescence microscopy, and 2) daily transportation of smear-negative sputum samples to Xpert® MTB/RIF testing sites. RESULTS: Of 1212 adults who underwent sputum testing for TB, 99.6% had two smears examined from the spot sputum specimen. Sputum was transported for Xpert testing within 1 clinic day for 83% (907/1091) of the smear-negative patients. Of 157 (13%) patients with bacteriologically positive TB, 116 (74%) were identified using sputum smear microscopy and 41 (26%) using Xpert testing of smear-negative samples. Anti-tuberculosis treatment was initiated in 142 (90%) patients with bacteriologically positive TB, with a median time to treatment of 1 day for smear-positive patients and 6 days for smear-negative, Xpert-positive patients. CONCLUSION: The SIMPLE TB strategy led to successful incorporation of Xpert testing and rapid treatment initiation in the majority of patients with bacteriologically confirmed TB in a resource-limited setting.


Assuntos
Antituberculosos/uso terapêutico , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/diagnóstico , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Microscopia de Fluorescência/métodos , Pessoa de Meia-Idade , Projetos Piloto , Atenção Primária à Saúde/métodos , Escarro/microbiologia , Fatores de Tempo , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
8.
J Laryngol Otol ; 130(4): 380-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26991876

RESUMO

OBJECTIVE: This study aimed to develop a functional model of subglottic stenosis by inducing direct airway irritation in transplanted mouse laryngotracheal complexes. METHODS: Laryngotracheal complexes from C57BL/6 mice were harvested and divided into three groups: uninjured, mechanically injured and chemically injured. Donor laryngotracheal complexes from each group were placed in dorsal subcutaneous pockets of recipient mice. Each week, the transplanted laryngotracheal complexes were harvested, and tissues were fixed, sectioned, and stained with haematoxylin and eosin. Representative slides were reviewed by a blinded pathologist, to determine the formation of granulation tissue, and graded as to the degree of granulation formation. RESULTS: Direct airway irritation induced granulation tissue formation under the disrupted epithelium of airway mucosa; this was seen as early as two weeks after chemical injury. CONCLUSION: Results indicate that granulation tissue formation in a murine model may be an efficient tool for investigating the development and treatment of subglottic stenosis.


Assuntos
Tecido de Granulação/patologia , Laringoestenose/patologia , Animais , Modelos Animais de Doenças , Laringoestenose/induzido quimicamente , Laringe/patologia , Laringe/transplante , Camundongos , Camundongos Endogâmicos C57BL , Traqueia/patologia , Traqueia/transplante
9.
Anesth Prog ; 52(3): 91-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16252738

RESUMO

This study with 24 volunteers compared the discomfort produced by needle penetration in different parts of the palatal mucosa. In addition, comparing a fresh needle to one that was used for a previous penetration in the same patient, we assessed the influence of the status of the needle on insertion discomfort during buccal mucosal penetration. The results showed that needle penetration in the anterior hard palate was more uncomfortable than in the posterior palate. Although men could not differentiate between fresh and used needles for a second buccal mucosal penetration, women reported a significant increase in discomfort with used needles.


Assuntos
Anestesia Dentária/instrumentação , Anestésicos Locais/administração & dosagem , Dor Facial/etiologia , Injeções/efeitos adversos , Agulhas/efeitos adversos , Administração Bucal , Adulto , Análise de Variância , Método Duplo-Cego , Reutilização de Equipamento , Feminino , Humanos , Injeções/instrumentação , Masculino , Mucosa Bucal , Medição da Dor , Palato Duro , Fatores Sexuais
10.
Biomed Res Int ; 2015: 910267, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26229966

RESUMO

Atrial fibrillation (AF) is the commonest sustained arrhythmia globally and results in significantly increased morbidity and mortality including a fivefold risk of stroke. Paroxysmal atrial fibrillation (PAF) constitutes approximately half of all AF cases and is thought to represent an early stage of the disease. This intermittent form of atrial arrhythmia can be a challenge to identify and as a result many affected individuals are not prescribed appropriate antithrombotic therapy and hence are at risk of stroke and thromboembolism. Despite these adverse outcomes there have been relatively few diagnostic advances in the field since the introduction of the Holter monitor in 1949. This review aims to establish the available evidence for electrophysiological, molecular, and morphological biomarkers to improve the detection of PAF with reference to the underlying mechanisms for the condition.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/sangue , Biomarcadores/sangue , Humanos
11.
Mayo Clin Proc ; 76(11): 1167-70, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702906

RESUMO

We report a case of Waterhouse-Friderichsen syndrome associated with group A streptococcus (GAS) toxic shock syndrome in a previously healthy man. The patient presented with neck pain and fevers of 2 days' duration. Computed tomography of the neck revealed a mass in the retropharyngeal space, suggesting an abscess. Despite prompt treatment with appropriate antibiotics, the patient experienced a fulminant course and died within 8 hours of presentation. Antemortem blood cultures grew GAS positive for exotoxins A, B, and C. Postmortem examination revealed bilateral adrenal hemorrhage, consistent with Waterhouse-Friderichsen syndrome. Immunohistochemical analysis of the adrenal glands revealed the presence of GAS antigens. However, no disseminated intravascular coagulation was evident. This case demonstrates that adrenal hemorrhage can occur without associated coagulopathy and may result directly from the action of bacterial toxins.


Assuntos
Antibacterianos/uso terapêutico , Choque Séptico/complicações , Infecções Estreptocócicas/complicações , Streptococcus pyogenes/isolamento & purificação , Síndrome de Waterhouse-Friderichsen/microbiologia , Glândulas Suprarrenais/patologia , Adulto , Evolução Fatal , Humanos , Masculino , Síndrome de Waterhouse-Friderichsen/fisiopatologia
12.
Chest ; 105(3): 947-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8131573

RESUMO

A patient with adult acid maltase deficiency (AMD) developed severe obstructive sleep apnea (OSA) and respiratory insufficiency. Weaning failure was followed by diffuse pneumonia and death. At autopsy, profound muscle replacement by fibrofatty tissue was noted in the tongue and diaphragm, while the accessory and nonrespiratory muscles were variably preserved. To our knowledge, this case represents the first detailed clinical description of OSA associated with adult AMD. In addition, we suggest that severe tongue weakness due to fatty metamorphosis, in concert with macroglossia, provides a unique pathophysiologic mechanism for OSA.


Assuntos
Glucana 1,4-alfa-Glucosidase/deficiência , Doença de Depósito de Glicogênio Tipo II/complicações , Macroglossia/etiologia , Síndromes da Apneia do Sono/etiologia , Língua/patologia , Doença de Depósito de Glicogênio Tipo II/patologia , Humanos , Macroglossia/patologia , Masculino , Pessoa de Meia-Idade , Músculos Respiratórios/patologia , Síndromes da Apneia do Sono/terapia , alfa-Glucosidases
13.
Br J Radiol ; 57(679): 581-4, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6428505

RESUMO

We have compared the 7-day retention of the radioisotope bile salt analogue SeHCAT (75Se-23-selena-25-homotaurocholate), by whole body counting and by uncollimated gamma camera measurement, in phantoms and in 25 patients with inflammatory bowel disease. The results correlate with a linear correlation coefficient of 0.96. An uncollimated gamma camera can be used to assess bile acid malabsorption when a whole body radioactivity monitor is not available.


Assuntos
Colite Ulcerativa/diagnóstico por imagem , Doença de Crohn/diagnóstico por imagem , Íleo/diagnóstico por imagem , Radioisótopos , Selênio , Ácido Taurocólico/análogos & derivados , Contagem Corporal Total , Colite Ulcerativa/metabolismo , Doença de Crohn/metabolismo , Humanos , Íleo/metabolismo , Absorção Intestinal , Métodos , Modelos Estruturais , Cintilografia , Selênio/metabolismo , Ácido Taurocólico/metabolismo
14.
J Med Eng Technol ; 15(4-5): 162-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1800747

RESUMO

PICS (portable imaging computer software), is a software system designed for handling and processing a variety of types of medical image. It has been designed to satisfy the following criteria: (a) the software should be portable between different items of hardware with minimal alteration; (b) there should be a simple operator interface to enable use by inexperienced users, while avoiding the need for experienced users to be directed through tedious menu trees; (c) the programming environment should enable simple integration of new data handling protocols. To meet these requirements the software was written in FORTRAN using structured subroutine organization. The software has basic image handling and processing facilities and contains a comprehensive set of nuclear medicine clinical protocols. Other facilities include alignment of images from different modalities with display of superimposed images and ability to handle, analyse and display three-dimensional data sets. Data transfer programs have been written to capture data from gamma camera, CT, MRI, ultrasound and radiographs by converting the images to a common data format. The system provides a hospital with a central digital image handling resource, enabling investigation of the value of digital image processing in potential clinical applications.


Assuntos
Processamento de Imagem Assistida por Computador , Software , Diagnóstico por Imagem/métodos , Desenho de Equipamento , Sistemas de Informação Hospitalar , Linguagens de Programação , Reino Unido , Interface Usuário-Computador
15.
J Phys Chem B ; 118(18): 4895-905, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24712560

RESUMO

In order to expand our understanding of a potential zinc-based battery electrolyte, we have characterized the physical and transport properties of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium dicyanamide ([C4mpyr][dca]) containing various levels of both Zn(2+) and H2O. Detailed measurements of density, viscosity, conductivity, and individual anion and cation diffusion coefficients using pulsed-field-gradient (PFG) NMR combined with NMR chemical shifts and spin-lattice relaxation (T1) NMR experiments provide insights into the motion and chemical environment of all molecular species. We find that the various techniques for probing ion transport and dynamics form a coherent picture as a function of electrolyte composition. Zn(2+) addition causes a moderate reduction in the self-diffusion of the IL anion and cation, whereas the addition of H2O increases ion mobility by increasing the liquid's overall fluidity. Temperature-dependent (13)C T1 experiments of the dca carbon analyzed using Bloembergen-Purcell-Pound fits show monotonic slowing of anion dynamics with Zn(2+) addition, suggesting increased Zn(2+)/dca(-) association. T1 experiments show minimal change in the spin-lattice relaxation of cation or anion upon H2O addition, suggesting that H2O is playing no significant role in Zn(2+) speciation. Finally, we employ a novel electrophoretic NMR technique to directly determine the electrophoretic mobility of the C4mpyr cation, which we discuss in the context of impedance-based conductivity measurements.

20.
Can Vet J ; 31(2): 118, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17423513
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