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1.
Int J Cosmet Sci ; 39(5): 511-517, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28493610

RESUMO

BACKGROUND: Xerosis is an abnormally dry and flaky skin condition that is associated with a change in the packing behaviour of the lipid matrix in the stratum corneum (SC), the outermost layer of the skin. This skin condition can lead to an increase in transepidermal water loss (TEWL). As ultralong-chain fatty acids have a positive effect on maintaining the packing behaviour of the SC lipid matrix, a moisturizer which contains glycerides of ultralong-chain fatty acids could act as a semi-occlusive layer on the surface of the skin. This will lower the rate of water evaporation through the epidermis and consequently help prevent or improve skin xerosis. OBJECTIVE: To identify a novel source of ultralong-chain lipids and develop monoacylglycerols with mixed fatty acyl chain lengths that have occlusive properties superior to petrolatum. METHODS: Initially, Performacol 425, a mixture of very long-chain fatty alcohols, was fractionated using short path distillation to yield a fraction enriched with C22:0-C26:0 fatty alcohols. The fatty alcohol fraction was then oxidized using Jones reagent, and the resulting fatty acids were esterified with glycerol to yield the corresponding monoglycerides using Novozym 435. These were then evaluated using Fourier transform infrared spectroscopy, differential scanning calorimetry and water vapour transmission rate measurements. RESULTS: The monoacylglycerols enriched with C22:0-C26:0 displayed a melting point of 80°C and orthorhombic packing; packing behaviour mainly present in healthy SC. In addition, a phospholipid-structured emulsion containing 3% of the monoglycerides displayed occlusive properties superior to the vehicle containing 3% petrolatum jelly. CONCLUSIONS: Performacol 425 can be a potential source of fatty alcohols to synthesize monoacylglycerols that can improve the occlusive behaviour of phospholipid-structured emulsions.


Assuntos
Álcoois/química , Monoglicerídeos/química , Creme para a Pele , Varredura Diferencial de Calorimetria , Cromatografia Gasosa , Cromatografia em Camada Fina , Emulsões , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Int J Cosmet Sci ; 39(2): 206-216, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27614102

RESUMO

OBJECTIVE: The focus of this communication was to study phospholipid-structured emulsions whose phase behaviour is modified with monoalkyl fatty amphiphiles. Ideally, these systems would mimic key physical and structural attributes observed in human stratum corneum (SC) so that they better alleviate xerotic skin conditions. METHODS: Phosphatidylcholine-structured emulsions were prepared, and their phase behaviour modified with monoalkyl fatty amphiphiles. The effect of molecular volume, acyl chain length and head-group interactions was studied using a combination of physical methods. Water vapour transmission rate (WVTR) was used as a primary test to assess occlusive character. Changes in the vibrational modes observed in Fourier transform infrared (FTIR) spectroscopy and bilayer spacing measured by X-ray diffraction (XRD) were then applied to elucidate the lateral and lamellar microstructural characteristics in the systems. RESULTS: Water vapour transmission rate demonstrated that as the phosphatidylcholine acyl chain length increased from C14, to C18, to C22, there was a corresponding increase in occlusive character. The addition of monoalkyl fatty amphiphiles such as behenic acid, behenyl alcohol or cetostearyl alcohol to a base formulation incorporating dipalmitoyl and distearoylphosphatidylcholine (C18) was seen to further increase barrier characteristics of the emulsions. FTIR methods used to probe lipid-chain conformational ordering demonstrated that as phosphatidylcholine acyl chain lengths increased, there was a corresponding improvement in acyl chain ordering, with an increase in thermal transition temperatures. The addition of a monoalkyl fatty amphiphile resulted in conformational order and thermal transition temperature improvements trending towards those observed in stratum corneum. FTIR also demonstrated that systems containing behenic acid or behenyl alcohol exhibited features associated with orthorhombic character. X-ray diffraction data showed that addition of monoalkyl fatty amphiphile also resulted in thicker lamellar structures than when those agents are not present. CONCLUSION: The generalized approach described herein is shown to mechanistically describe the occlusive character of phospholipid-structured formulations in the presence of long-chain fatty acids or alcohols and that they exhibit characteristics mimicking those found in human SC lipids.


Assuntos
Biomimética , Composição de Medicamentos , Desenho de Fármacos , Lipídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Int J Cosmet Sci ; 39(2): 217-223, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27643384

RESUMO

OBJECTIVES: The present work analysed the antioxidative activity of phenol-based antioxidants using an electron spin resonance method to predict the activity and stability of these antioxidants in cosmetic products. METHODS: The antioxidative power (AP) method was chosen to measure both the capacity and kinetics of an antioxidative reaction by detecting the DPPH (diphenylpicrylhydrazyl) radical. The antioxidative capacity (wc ) relates to the amount of free radicals that can be reduced, whereas the antioxidative reactivity (tr ) relates to the reaction speed and offers a fingerprinting of the redox state of the antioxidant molecules. Fifteen phenolic molecules have been analysed. They differed in the position of the hydroxyl groups and substituents on the aromatic ring. The AP of two distinct formulations containing hydroxytyrosol is presented as well as three phenol-based antioxidants within the same formulation vehicle. RESULTS: The rate at which phenol (ArOH) reacts with DPPH radicals, defined by the term reactivity (tr ) in this paper, was dependent upon the bond dissociation enthalpy (BDE) of the OH bond. Molecules having weak OH bonds and consequently low BDE values showed high antioxidant reactivity. On the other hand, the capacity factor (wc ), which is the concentration of phenol required to reduce a fixed concentration of DPPH radical, depends on the number and position of hydroxyl groups. The results showed that ortho and para positions of the two hydroxyl groups are important for higher capacity. If one of the two hydroxyl groups is blocked by methylation, both the antioxidative capacity and reactivity are reduced, mainly for ortho disubstituted compounds. The presence of a vinylic side chain improved reactivity and capacity tremendously. AP values may be useful in formulation design when identifying antioxidants that are likely to be physically and chemically stable. The importance of optimization of the formulation vehicle itself for a given antioxidant is also illustrated. CONCLUSION: Based on the presented findings, it is possible to predict the antioxidative performance of a phenol-based molecule and its stability and oxidation resistance within a cosmetic formulation. This is essential for antioxidant containing dermal formulations designed to combat skin ageing.


Assuntos
Antioxidantes/farmacologia , Fenóis/farmacologia , Pele/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade
4.
BMC Med Educ ; 15: 237, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26715145

RESUMO

BACKGROUND: Evaluations of clinical assessments that use judgement-based methods have frequently shown them to have sub-optimal reliability and internal validity evidence for their interpretation and intended use. The aim of this study was to enhance that validity evidence by an evaluation of the internal validity and reliability of competency constructs from supervisors' end-of-term summative assessments for prevocational medical trainees. METHODS: The populations were medical trainees preparing for full registration as a medical practitioner (74) and supervisors who undertook ≥2 end-of-term summative assessments (n = 349) from a single institution. Confirmatory Factor Analysis was used to evaluate assessment internal construct validity. The hypothesised competency construct model to be tested, identified by exploratory factor analysis, had a theoretical basis established in workplace-psychology literature. Comparisons were made with competing models of potential competency constructs including the competency construct model of the original assessment. The optimal model for the competency constructs was identified using model fit and measurement invariance analysis. Construct homogeneity was assessed by Cronbach's α. Reliability measures were variance components of individual competency items and the identified competency constructs, and the number of assessments needed to achieve adequate reliability of R > 0.80. RESULTS: The hypothesised competency constructs of "general professional job performance", "clinical skills" and "professional abilities" provides a good model-fit to the data, and a better fit than all alternative models. Model fit indices were χ2/df = 2.8; RMSEA = 0.073 (CI 0.057-0.088); CFI = 0.93; TLI = 0.95; SRMR = 0.039; WRMR = 0.93; AIC = 3879; and BIC = 4018). The optimal model had adequate measurement invariance with nested analysis of important population subgroups supporting the presence of full metric invariance. Reliability estimates for the competency construct "general professional job performance" indicated a resource efficient and reliable assessment for such a construct (6 assessments for an R > 0.80). Item homogeneity was good (Cronbach's alpha = 0.899). Other competency constructs are resource intensive requiring ≥11 assessments for a reliable assessment score. CONCLUSION: Internal validity and reliability of clinical competence assessments using judgement-based methods are acceptable when actual competency constructs used by assessors are adequately identified. Validation for interpretation and use of supervisors' assessment in local training schemes is feasible using standard methods for gathering validity evidence.


Assuntos
Competência Clínica/normas , Avaliação Educacional/normas , Corpo Clínico Hospitalar/normas , Pessoal Administrativo/normas , Austrália , Certificação/normas , Avaliação Educacional/métodos , Análise Fatorial , Feminino , Humanos , Julgamento , Masculino , Psicometria , Reprodutibilidade dos Testes
5.
Adv Health Sci Educ Theory Pract ; 18(4): 701-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23053869

RESUMO

Supervisor assessments are critical for both formative and summative assessment in the workplace. Supervisor ratings remain an important source of such assessment in many educational jurisdictions even though there is ambiguity about their validity and reliability. The aims of this evaluation is to explore the: (1) construct validity of ward-based supervisor competency assessments; (2) reliability of supervisors for observing any overarching domain constructs identified (factors); (3) stability of factors across subgroups of contexts, supervisors and trainees; and (4) position of the observations compared to the established literature. Evaluated assessments were all those used to judge intern (trainee) suitability to become an unconditionally registered medical practitioner in the Australian Capital Territory, Australia in 2007-2008. Initial construct identification is by traditional exploratory factor analysis (EFA) using Principal component analysis with Varimax rotation. Factor stability is explored by EFA of subgroups by different contexts such as hospital type, and different types of supervisors and trainees. The unit of analysis is each assessment, and includes all available assessments without aggregation of any scores to obtain the factors. Reliability of identified constructs is by variance components analysis of the summed trainee scores for each factor and the number of assessments needed to provide an acceptably reliable assessment using the construct, the reliability unit of analysis being the score for each factor for every assessment. For the 374 assessments from 74 trainees and 73 supervisors, the EFA resulted in 3 factors identified from the scree plot, accounting for only 68 % of the variance with factor 1 having features of a "general professional job performance" competency (eigenvalue 7.630; variance 54.5 %); factor 2 "clinical skills" (eigenvalue 1.036; variance 7.4 %); and factor 3 "professional and personal" competency (eigenvalue 0.867; variance 6.2 %). The percent trainee score variance for the summed competency item scores for factors 1, 2 and 3 were 40.4, 27.4 and 22.9 % respectively. The number of assessments needed to give a reliability coefficient of 0.80 was 6, 11 and 13 respectively. The factor structure remained stable for subgroups of female trainees, Australian graduate trainees, the central hospital, surgeons, staff specialist, visiting medical officers and the separation into single years. Physicians as supervisors, male trainees, and male supervisors all had a different grouping of items within 3 factors which all had competency items that collapsed into the predefined "face value" constructs of competence. These observations add new insights compared to the established literature. For the setting, most supervisors appear to be assessing a dominant construct domain which is similar to a general professional job performance competency. This global construct consists of individual competency items that supervisors spontaneously align and has acceptable assessment reliability. However, factor structure instability between different populations of supervisors and trainees means that subpopulations of trainees may be assessed differently and that some subpopulations of supervisors are assessing the same trainees with different constructs than other supervisors. The lack of competency criterion standardisation of supervisors' assessments brings into question the validity of this assessment method as currently used.


Assuntos
Competência Clínica/normas , Avaliação de Desempenho Profissional/normas , Corpo Clínico Hospitalar , Território da Capital Australiana , Análise Fatorial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
6.
Biochim Biophys Acta ; 1800(3): 392-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20004233

RESUMO

alpha-Crystallin, one of the main constituent proteins in the crystalline lens, is an important molecular chaperone both within and outside the lens. Presently, the structural relationship between alpha-crystallin and its target proteins during chaperone action is poorly understood. It has been hypothesised that target proteins bind within a central cavity. Small-angle neutron-scattering (SANS) experiments in conjunction with isotopic substitution were undertaken to investigate the interaction of a target lens protein (gammaE-crystallin) with alpha-crystallin (alpha(H)) and to measure the radius of gyration (Rg) of the proteins and their binary complexes in solution under thermal stress. The size of the alpha(H) in D(2)O incubated at 65 degrees C increased from 69+/-3 to 81+/-5 A over 40 min, in good agreement with previously published small-angle X-ray scattering (SAXS) and SANS measurements. Deuterated gammaE-crystallin in H(2)O buffer (gammaE(D)/H(2)O) and hydrogenous gammaE-crystallin in D(2)O buffer (gammaE(H)/D(2)O) free in solution were of insufficient size and/or too dilute to provide any measurable scattering over the angular range used, which was selected primarily to investigate gammaE:alpha(H) complexes. The evolution of the aggregation size/shape as an indicator of alpha(H) chaperone action was monitored by recording the neutron scattering in different H:D solvent contrasts under thermally stressed conditions (65 degrees C) for binary mixtures of alpha(H), gammaE(H), and gammaE(D). It was found that Rg(alpha(H):gammaE(D)/D(2)O)>Rg(alpha(H):gammaE(H)/D(2)O)>Rg(alpha(H)/D(2)O) and that Rg(alpha(H):gammaE(H)/D(2)O) approximately Rg(alpha(H)/D(2)O). The relative sizes observed for the complexes weighted by the respective scattering powers of the various components imply that gammaE-crystallin binds in a central cavity of the alpha-crystallin oligomer, during chaperone action.


Assuntos
Cristalino/metabolismo , alfa-Cristalinas/metabolismo , gama-Cristalinas/metabolismo , Animais , Bovinos , Peso Molecular , Nêutrons , Espalhamento de Radiação , Software , Solventes , Termodinâmica , alfa-Cristalinas/química , gama-Cristalinas/química , gama-Cristalinas/isolamento & purificação
7.
Eur J Vasc Endovasc Surg ; 41(1): 38-40, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21074461

RESUMO

Challenging access situations continue to arise in endovascular aneurysm repair, despite evolving arterial access techniques. We report a modified access approach, where an ascending aortic conduit was successfully used for antegrade delivery of a thoracic endograft to repair a descending thoracic aortic aneurysm, in a patient with previous surgical ligation of the infra-renal aorta.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Próteses Valvulares Cardíacas , Angiografia Digital , Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Humanos , Ligadura , Masculino , Pessoa de Meia-Idade , Polietilenotereftalatos , Tomografia Computadorizada por Raios X
8.
Adv Health Sci Educ Theory Pract ; 16(3): 405-25, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21607744

RESUMO

Even though rater-based judgements of clinical competence are widely used, they are context sensitive and vary between individuals and institutions. To deal adequately with rater-judgement unreliability, evaluating the reliability of workplace rater-based assessments in the local context is essential. Using such an approach, the primary intention of this study was to identify the trainee score variation around supervisor ratings, identify sampling number needs of workplace assessments for certification of competence and position the findings within the known literature. This reliability study of workplace-based supervisors' assessments of trainees has a rater-nested-within-trainee design. Score variation attributable to the trainee for each competency item assessed (variance component) were estimated by the minimum-norm quadratic unbiased estimator. Score variance was used to estimate the number needed for a reliability value of 0.80. The trainee score variance for each of 14 competency items varied between 2.3% for emergency skills to 35.6% for communication skills, with an average for all competency items of 20.3%; the "Overall rating" competency item trainee variance was 28.8%. These variance components translated into 169, 7, 17 and 28 assessments needed for a reliability of 0.80, respectively. Most variation in assessment scores was due to measurement error, ranging from 97.7% for emergency skills to 63.4% for communication skills. Similar results have been demonstrated in previously published studies. In summary, overall supervisors' workplace based assessments have poor reliability and are not suitable for use in certification processes in their current form. The marked variation in the supervisors' reliability in assessing different competencies indicates that supervisors may be able to assess some with acceptable reproducibility; in this case communication and possibly overall competence. However, any continued use of this format for assessment of trainee competencies necessitates the identification of what supervisors in different institutions can reliably assess rather than continuing to impose false expectations from unreliable assessments.


Assuntos
Competência Clínica/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Avaliação Educacional/métodos , Análise de Variância , Avaliação Educacional/estatística & dados numéricos , Escolaridade , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos , Local de Trabalho/psicologia
9.
Eur J Vasc Endovasc Surg ; 39(2): 217-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19939710

RESUMO

Aortoenteric fistulae are infrequent causes of gastrointestinal bleeding and usually occur as a late complication of aortic aneurysm repair. Primary aortoenteric fistulae are very rare and most have an aetiological association with atherosclerotic aneurysmal disease.(1,2) We report a primary aortoenteric fistula (PAEF) occurring in a 3 year old as a result of duodenal perforation after ingestion of a twig. To our knowledge this is the first case of a primary aortoenteric fistula reported in a child. Emergency aortic surgery in children needs certain considerations which are briefly discussed.


Assuntos
Doenças da Aorta/etiologia , Duodenopatias/etiologia , Corpos Estranhos/complicações , Fístula Intestinal/etiologia , Fístula Vascular/etiologia , Doenças da Aorta/diagnóstico , Doenças da Aorta/cirurgia , Pré-Escolar , Diagnóstico Diferencial , Duodenopatias/diagnóstico , Duodenopatias/cirurgia , Corpos Estranhos/diagnóstico , Corpos Estranhos/cirurgia , Humanos , Fístula Intestinal/diagnóstico , Fístula Intestinal/cirurgia , Masculino , Fístula Vascular/diagnóstico , Fístula Vascular/cirurgia , Madeira
10.
Int J Clin Pract ; 63(6): 841-54, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19490195

RESUMO

BACKGROUND: Randomised controlled trials are the most effective way to differentiate between the effects of competing interventions. However, head-to-head studies are unlikely to have been conducted for all competing interventions. AIM: Evaluation of different methodologies used to indirectly compare interventions based on meta analyses of randomised controlled trials. METHODS: Systematic review of Cochrane Database of Systematic Reviews, Cochrane Methodology Register, EMBASE and MEDLINE for reports including meta analyses that contained an indirect comparison. Searching was completed in July 2007. No restriction was placed on language or year of publication. RESULTS: Sixty-two papers identified contained indirect comparisons of treatments. Five different methodologies were employed: comparing point estimates (1/62); comparing 95% confidence intervals (26/62); performing statistical tests on summary estimates (8/62); indirect comparison using a single common comparator (20/62); and mixed treatment comparison (MTC) (7/62). The only methodologies that provide an estimate of the difference between the interventions under consideration and a measure of the uncertainty around that estimate are indirect comparison using a single common comparator and MTC. The MTC might have advantages over other approaches because it is not reliant on a single common comparator and can incorporate the results of direct and indirect comparisons into the analysis. Indirect comparisons require an underlying assumption of consistency of evidence. Utilising any of the methodologies when this assumption is not true can produce misleading results. CONCLUSIONS: Use of either indirect comparison using a common comparator or MTC provides estimates for use in decision making, with the preferred methodology being dependent on the available data.


Assuntos
Pesquisa Comparativa da Efetividade , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Intervalos de Confiança , Projetos de Pesquisa , Resultado do Tratamento
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(4 Pt 1): 041701, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17500907

RESUMO

In this paper, we report on the flexoelastic and viscoelastic ratios for a number of bimesogens compounds with the same generic structure. Values are obtained indirectly by measuring the flexoelectro-optic response in the chiral nematic phase. By varying the molecular structure we alter the bend angle, transverse dipole moment, and length of the molecule. First, to examine the influence of the bend angle we use a homologous series whereby the only alteration in the molecular structure is the number of methylene units in the aliphatic spacer, n . Results show that the flexoelastic ratio, e/K , and the effective flexoelectric coefficient, e , both exhibit an odd-even effect with values for n=odd being greater than that for n=even . This is understood in terms of an increase in the bend angle of the molecule and an increase in the transverse dipole moment. Second, in order to investigate the impact of the dipole moment, we have altered the mesogenic units so as to vary the longitudinal dipole moment and used different linkages in the aliphatic spacer in an attempt to alter the transverse dipole moment. Qualitatively, the results demonstrate that the odd-spaced bimesogen with larger transverse dipole moments exhibit larger flexoelastic ratios.

12.
J Colloid Interface Sci ; 490: 137-146, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27870954

RESUMO

A series of O-acylated-ω-hydroxy fatty acids (Acyl acids) of up to 34 carbons were synthesized and characterized through DSC, FTIR and Langmuir isotherm measurements to identify potential replacements to petrolatum, a highly used occlusive technology that if unrefined, it can potentially be classified as carcinogenic. Fourier transform infrared spectroscopy studies demonstrated that long acyl acids engender orthorhombic packing; packing behavior that is predominant in the lipid matrix of healthy stratum corneum, the outmost layer of the skin. In addition, Differential Scanning Calorimetry (DSC) and Langmuir isotherm studies suggested that the length of the hydrocarbon chain and the position of the ester bond influence the molecular organization of the acyl acids. For instance, 16-(tetradecanoyloxy)hexadecanoic acid (30 carbons) displayed a higher melting point (mp=68°C) than 10-(stearoyloxy)decanoic acid (28 carbons; mp=63°C) and 10-(tetradecanoyloxy)decanoic acid (24 carbons; mp=55°C) according to DSC. Moreover, Langmuir isotherm studies showed that mixtures of acyl acid with distearoylphosphatidylcholine improved packing behavior. Finally, Water Vapor Transmission Rate (WVTR) measurements showed that the compounds in fact decrease WVTR compared to untreated control (P<0.001) which demonstrates the potential of these ingredients as occlusive technologies to combat skin barrier diseases.


Assuntos
Ácidos Graxos/química , Substâncias Protetoras/química , Acilação , Varredura Diferencial de Calorimetria , Ácidos Graxos/síntese química , Humanos , Modelos Moleculares , Substâncias Protetoras/síntese química , Pele/química , Pele/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor/análise
13.
J Neurosurg Sci ; 50(2): 41-4, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16841026

RESUMO

Two patients presenting with intradural, extramedullary, transforaminal ''dumbbell-shaped'' tumors are discussed. While imaging studies were strongly suggestive of schwannoma, both patients were diagnosed with meningioma. Presentation, imaging studies, operative intervention and pathology are described. Due to the difficulty in achieving complete resection, and the propensity for recurrence, long-term follow-up is recommended.


Assuntos
Vértebras Cervicais/patologia , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Neurilemoma/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Neurilemoma/patologia
14.
Singapore Med J ; 47(12): 1092-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17139410

RESUMO

Lemierre's syndrome is an oropharyngeal infection leading to secondary septic thrombophlebitis of the internal jugular vein (IJV). It is classically anaerobic in origin and Fusobacterium necrophorum is the commonest pathogen. We report an unusual variant of this condition in a 68-year-man with uncontrolled diabetes mellitus who presented with extensive cellulitis of the left neck. No primary oropharyngeal sepsis was detected. Neck radiographs revealed soft tissue gas and computed tomography confirmed neck space infection with gas formation and complete thrombosis of the left IJV. Klebsiella pneumoniae was isolated from the fluid, tissue and blood samples. Repeated debridement was required until complete healing. Computed tomography of the neck at six months showed resolution of infection, although the vein remained thrombosed. Although the radiological features resemble Lemierre's syndrome, this case differs from it in the absence of oropharyngeal sepsis and presence of background diabetes mellitus. The isolation of Klebsiella pneumoniae as a cause has not been previously described.


Assuntos
Celulite (Flegmão)/microbiologia , Complicações do Diabetes/microbiologia , Infecções por Klebsiella/complicações , Tromboflebite/etiologia , Idoso , Celulite (Flegmão)/diagnóstico por imagem , Celulite (Flegmão)/cirurgia , Humanos , Veias Jugulares/diagnóstico por imagem , Veias Jugulares/microbiologia , Veias Jugulares/patologia , Infecções por Klebsiella/sangue , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/patogenicidade , Masculino , Radiografia , Síndrome , Tromboflebite/diagnóstico por imagem , Tromboflebite/microbiologia
15.
J Clin Oncol ; 16(3): 830-43, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9508163

RESUMO

PURPOSE: To assess the effect of more extensive radiotherapy and of adjuvant combination chemotherapy on long-term outcome of early-stage Hodgkin's disease. METHODS: In a collaborative worldwide systematic overview, individual patient data were centrally reviewed on 1,974 patients in eight randomized trials of more versus less extensive radiotherapy and on 1,688 patients in 13 trials of radiotherapy plus chemotherapy versus radiotherapy alone. Crude mortality data on 226 patients in two other trials of chemotherapy were also reviewed. RESULTS: More extensive radiotherapy reduced the risk of treatment failure (resistant or recurrent disease) at 10 years by more than one third (31.3% v 43.4% failures; P < .00001), but there was no apparent improvement in overall 10-year survival (77.1 % v 77.0% alive). The addition of chemotherapy to radiotherapy halved the 10-year risk of failure (15.8% v 32.7%; P < .00001), with a small, nonsignificant improvement in survival (79.4% v 76.5% alive). This involved a reduction of borderline significance for deaths from Hodgkin's disease (12.3% v 15.4% dead at 10 years; P = .07), which was partly counterbalanced by a nonsignificant excess of deaths from other causes (12.4% v 10.0% 10-year risk). CONCLUSION: More extensive radiotherapy fields or the addition of chemotherapy to radiotherapy in the initial treatment of early-stage Hodgkin's disease had a large effect on disease control, but only a small effect on overall survival. Recurrences could be prevented by more extensive radiotherapy or by additional chemotherapy. However, if chemotherapy had not been given initially, recurrences were generally salvageable by re-treatment with chemotherapy. Hence, less intensive primary treatment--particularly a reduction in radiotherapy fields--appears to achieve similar survival rates as more intensive treatment, although more randomized evidence is needed to confirm this.


Assuntos
Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Doença de Hodgkin/mortalidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estatística como Assunto , Análise de Sobrevida , Resultado do Tratamento
16.
Water Sci Technol ; 51(3-4): 39-46, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15850172

RESUMO

The sodium dominance index was developed to quantify weathering rates and critical loads in Scotland, where atmospheric aerosols of maritime origin dominate over biogeochemical weathering in providing base cation inputs to catchment soils and drainage waters. High sodium dominance in river or lake water indicates low weathering rate. Here, this concept is evaluated using intensive temporal and spatial sampling strategies in two substantial catchments, one in Scotland and the other in central England, with particular reference to detection of groundwater inputs, and to possible problems from road salting in the calibration. In the Dee network, the spatial distribution of sodium dominance reflects the distribution of soil parent material geology, but land use also influences the equations. It is postulated that road density, via winter road salting, influences the sodium dominance calibration in lowland agricultural areas. Although road salting can also be problematic in some upland areas, the index still can provide clear indication of the likely severity of acid flush events in remote upland streams. In the Etherow catchment, sodium dominance varies markedly, sometimes over relatively small distances, reflecting soil type distribution, the occurrence of ground-water inputs to streams, and the influence of water in tributaries above the sampling point.


Assuntos
Conservação dos Recursos Naturais , Sódio/análise , Abastecimento de Água , Inglaterra , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Modelos Teóricos , Rios , Escócia , Movimentos da Água , Tempo (Meteorologia)
17.
J Neurosurg Sci ; 59(2): 181-93, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25649066

RESUMO

ìTumors of the spine, though rare, may significantly impact quality of life. The management depends not only on clinical presentation, but also on histology, stage and grade of the tumor. Primary benign tumors usually are a focal problem, however, may be focally aggressive. Primary malignant tumors are always considered aggressive and are managed in a multidisciplinary fashion. Surgical treatment often requires aggressive en bloc resection to maximize potential for cure. Metastatic tumors of the spine may cause a significant impact on the quality of life. In select cases with spine instability, pain and neurologic deficit surgical management is indicated.


Assuntos
Neoplasias da Coluna Vertebral/cirurgia , Humanos , Qualidade de Vida
18.
BJR Case Rep ; 1(3): 20150017, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30363658

RESUMO

Pseudoangiomatous stromal hyperplasia (PASH) is a benign breast disorder with the tumoral variety being extremely rare. We report a rare case of synchronous, massive axillary and breast tumoral PASH in a 55-year-old post-menopausal woman. Mammography, ultrasonography and sonoelastography features are illustrated with histopathological correlation. A high-grade invasive ductal carcinoma was detected in the contralateral breast on annual follow-up imaging. Radiologists need to be familiar with the imaging appearances of PASH and be aware of its association with subsequent cancer risk. To the best of our knowledge, the present case of synchronous tumoral PASH in the breast and axillary tissue is the second reported case till now.

19.
J Endocrinol ; 116(3): 349-56, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2895160

RESUMO

Primary cultures of rat hypothalamic neurones were maintained either in a serum-supplemented medium or in a serum-free chemically defined medium for up to 6 weeks. The release of the 41 amino acid-containing peptide, corticotrophin-releasing factor (CRF-41), vasopressin (AVP) and somatostatin (SRIF) were followed using immunoassays. In response to K+ (56 mmol/l) depolarization both the quantities of peptides released and the magnitude of responses were significantly greater from cultures maintained in the fully supplemented defined medium. As a consequence, release of CRF-41 and AVP could be measured directly, without requiring the concentration step necessary for cultures grown in serum. The response to K+ depolarization increased with the age of the culture, suggesting neuronal maturation. Responses to K+ depolarization were Ca2+-dependent, and the addition of corticosterone (100 nmol/l) to the defined medium caused a significant reduction in the response of neurones secreting CRF-41 and AVP, but not those secreting SRIF, to depolarization. This suggests the retention in vitro of the responsiveness of stress-associated neuropeptides to the negative feedback effects of corticosterone. Neurones producing CRF-41 and AVP responded significantly in a dose-dependent manner to acetylcholine stimulation, whereas those producing SRIF did not. As cultures matured, the CRF-41- and AVP-producing neurones became more sensitive to acetylcholine with the maximal response at 1 nmol acetylcholine/l. In conclusion, the culture of rat hypothalamic neurones is improved in terms of peptide output when the cultures are maintained in a defined medium.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hipotálamo/metabolismo , Neurônios/metabolismo , Peptídeos/metabolismo , Animais , Arginina Vasopressina/metabolismo , Sangue , Células Cultivadas , Hormônio Liberador da Corticotropina/metabolismo , Meios de Cultura , Neurônios/efeitos dos fármacos , Potássio/farmacologia , Ratos , Somatostatina/metabolismo
20.
Pediatr Infect Dis J ; 18(5): 451-5, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10353519

RESUMO

BACKGROUND: Kawasaki syndrome (KS) is a leading cause of acquired heart disease among US children, but the epidemiologic features of KS among American Indian and Alaska Native (AI/AN) children have not been described. METHODS: We examined Indian Health Service computerized records of hospital discharges for AI/AN children <18 years of age with KS during 1980 through 1995. RESULTS: During 1980 through 1995, 85 AI/AN children were reported with a hospitalization for KS; 10 of the children had an additional KS hospitalization record within 5 months. The average annual KS hospitalization rate for children <5 years of age, based on first KS hospitalization only, was 4.3 cases per 100000 children; the rate for children age <1 year (n = 21) was 8.6 per 100000 and for children ages 1 to 4 years was 3.6 per 100000. The annual rates for children < 5 years of age ranged from 0 to 8.5 per 100000 children. KS hospitalizations for children peaked in January and February; 50.6% of the children were hospitalized during January through April. The overall median length of hospital stay was 4 days (range, 1 to 29 days); the median duration decreased from 8 days from 1980 through 1982 to 4 days from 1993 through 1995. CONCLUSIONS: The overall annual hospitalization rate of KS among AI/AN children <5 years of age was slightly lower than rates for several majority white populations in the United States. (4.6 to 15.2 cases per 100000) and much lower than rates for blacks and Asians/Pacific Islanders.


Assuntos
Indígenas Norte-Americanos , Inuíte , Síndrome de Linfonodos Mucocutâneos/etnologia , Adolescente , Criança , Pré-Escolar , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Vigilância da População , Estados Unidos/epidemiologia , United States Indian Health Service
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