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1.
Radiography (Lond) ; 26(3): e179-e185, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32052790

RESUMEN

OBJECTIVES: The aim of this review is to explore the impact of educational interventions on clinicians' knowledge of radiation protection. KEY FINDINGS: Following a comprehensive search of MEDLINE and EMBASE from 2000 to 2018, 1795 studies were identified, eight of which met the criteria for this review. All eight studies utilised pretest-posttest designs and involved the education of medical students or doctors. All studies reported an increase in participants' knowledge of radiation protection, five of which were statistically significant. In two studies, over half of participants stated that education received would impact on their future imaging requesting practice. CONCLUSION: Whilst a range of educational interventions have been shown to improve knowledge of radiation protection, there was wide variation in the study settings and type of educational programmes delivered. No studies assessed long-term knowledge retention or the impact on clinical practice. Therefore, robust research is needed to accurately measure the impact of educational programmes on knowledge of radiation protection in the UK and the implications this may have on referral practices. IMPLICATIONS FOR PRACTICE: This review revealed that educational interventions are effective in increasing participants' knowledge levels of radiation protection. It is necessary to assess and ensure that this improvement in knowledge actually translates into an impact on referral practice/behaviour. The ideal outcome being that fewer unnecessary examinations are requested and our patients are protected from a needless increased radiation burden.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Protección Radiológica/métodos , Radiología/educación , Humanos
2.
Thorax ; 58(2): 116-21, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12554891

RESUMEN

BACKGROUND: The relationship between the clinical pattern of asthma and airway inflammation in childhood asthma is poorly characterised, yet underpins the treatment recommendations in current asthma guidelines. A study was undertaken to examine the relationship between airway inflammation and clinical asthma in children. METHODS: Children with asthma (n=146) and healthy controls (C, n=37) were recruited from primary and specialist clinics. Sputum induction and hypertonic saline challenge were performed. RESULTS: As the frequency of asthma episodes in the past 12 months increased, there were significant increases in sputum eosinophils (median; infrequent episodic (IE) 1.5%, frequent episodic (FE) 2.3%, persistent (P) 3.8%, control (C) 1.0%; p=0.002), sputum eosinophil cationic protein (ECP) (IE 113 ng/ml, FE 220, P 375, C 139; p=0.003), and desquamated bronchial epithelial cells (IE 2.0%, FE 6.0%, P 5.0%, C 2.5%; p=0.04). Treatment intensity was also associated with increased sputum eosinophils (p=0.005). The relationships between other severity markers (current symptoms, lung function) were less strong. CONCLUSION: Children with more frequent episodes of clinical asthma exhibit increasing airway inflammation that is characterised by sputum eosinophilia and bronchial epithelial desquamation. The results support clinical assessment by frequency of wheezing episodes over the past 12 months when determining anti-inflammatory treatment requirements, and indicate that current symptoms are determined by mechanisms in addition to sputum eosinophilia.


Asunto(s)
Asma/patología , Eosinófilos , Esputo/citología , Adolescente , Agonistas Adrenérgicos beta/uso terapéutico , Asma/tratamiento farmacológico , Asma/fisiopatología , Pruebas de Provocación Bronquial , Niño , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Recuento de Leucocitos , Masculino , Análisis de Regresión , Capacidad Vital/fisiología
3.
Am J Respir Crit Care Med ; 164(7): 1146-9, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11673200

RESUMEN

Induced sputum using hypertonic saline (HS) is a useful research tool to study airway inflammation (AI). HS provocation testing can also be used to measure airway hyperresponsiveness (AHR). A combined HS challenge and sputum induction procedure has been developed to permit assessment of AI and AHR in a single test. The aim of this study is to report the success and tolerability of sputum induction alone, and in combination with a HS bronchial provocation challenge. Sputum induction alone was performed with beta2-agonist pretreatment. In the combined challenge, no beta2-agonist pretreatment was used. A high-output ultrasonic nebulizer with valve box and tubing were used to deliver 4.5% saline in doubling time periods from 0.5 s to 4 min. Outcomes assessed were completion of the test protocol, adequacy of sputum samples, decrease in FEV1, and adverse effects during the procedure. Fifty-three children who underwent a sputum induction alone, and 182 children who underwent a combined sputum induction and bronchial provocation using HS. Sputum induction alone was well tolerated, with 98% of children completing the procedure and only 4% experiencing a significant (> 15%) fall in FEV1. An adequate sample of sputum was obtained in 92% of children. The combined challenge was completed by 90% of children. A distressing cough occurred in 13% of children and irritation of the mucosa in 1% of children. In the combined challenge an adequate sample of sputum was obtained in significantly fewer children than with sputum induction alone (70% versus 92%, p < 0.05). Sputum cellular changes reflected the shorter nebulization time with sputum induction alone. We conclude that induction of sputum using HS after pretreatment with bronchodilator is well tolerated with a high success rate in children. Combining the HS challenge with sputum induction provides additional information and is a useful means of comparing AHR and AI simultaneously, but at the expense of having a reduced success rate in obtaining an adequate sample of sputum, as well as increased side effects.


Asunto(s)
Asma/diagnóstico , Solución Salina Hipertónica , Esputo , Adolescente , Agonistas Adrenérgicos beta , Albuterol , Niño , Femenino , Humanos , Masculino
4.
Am J Clin Pathol ; 116(1): 41-50, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11447750

RESUMEN

We describe 2 male patients in whom hepatosplenic gamma/delta T-cell lymphoma (HSTL) developed 6 and 10 years after renal transplantation. The onset was abrupt with systemic symptoms, cytopenia, and hepatosplenomegaly. The histologic examination of the spleen (case 1), liver, and bone marrow revealed sinusoidal infiltrates of markedly abnormal lymphocytes. The neoplastic cells in these cases were CD2+, CD3+, CD4-, CD5-, CD7+, CD8+, CD16+, CD56+, beta F1-negative, and TIA-1-negative. Both cases displayed clonal rearrangement of the T-cell receptor (TCR) delta gene and the TCR beta gene. The spleen in case 1 was positive for Epstein-Barr virus genome and showed TCR-gamma gene rearrangement by polymerase chain reaction. Isochromosome 7 [i(7)(q10)] was found in each case. Both patients died within 4 months of diagnosis. HSTL has been reported in only 5 renal transplant recipients. HSTL may be relatively more frequent in immunocompromised patients compared with the general population.


Asunto(s)
Huésped Inmunocomprometido , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Neoplasias del Bazo/genética , Neoplasias del Bazo/inmunología , Adulto , Médula Ósea/metabolismo , Médula Ósea/patología , Análisis Citogenético , Humanos , Inmunofenotipificación , Terapia de Inmunosupresión/efectos adversos , Trasplante de Riñón , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Neoplasias del Bazo/etiología , Neoplasias del Bazo/patología
5.
Mol Ecol ; 10(6): 1527-37, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11412373

RESUMEN

Natal dispersal can have important effects on mammal population structure and dynamics following a local population crash. Such dispersal is of practical importance when applied to the control of pest species because dispersal may significantly, and undesirably, reduce the population recovery time following a control operation. The relative dispersal rate of the sexes is also critical because that too will affect the rate of population increase. Here, we describe a field experiment in which we reduce the density of two populations of the Australian brushtail possum, and use genetic similarity, as estimated by minisatellite DNA profiles, to investigate dispersal in the original (undisturbed) and recovering populations. Our results show that the genetic similarity within the undisturbed populations was lower between males than between females. Conversely, the genetic similarities between males and females in the two recovering populations were not significantly different, while relatedness among males was significantly higher in the recovering populations when compared with those in the pre-removal populations. These data indicate two important characteristics of dispersal in possums: (i) that dispersal in established populations is sex biased towards males; and (ii) that within the first 3 years following population control, 'the vacuum effect', whereby individuals from areas adjacent to a control area expand their home range and invade the depopulated area, is the most important factor in the re-colonization process for possums. We found no evidence that the mating system, which is polygynous, varied when the density was markedly reduced. These results indicate that drastic reductions in population density by conventional control will not affect the rate of spread of biological control agents that rely on sexual transmission for dissemination.


Asunto(s)
ADN Satélite , Genética de Población , Zarigüeyas/fisiología , Conducta Sexual Animal/fisiología , Animales , Australia , Femenino , Masculino , Nueva Zelanda , Paternidad
6.
Arch Pathol Lab Med ; 123(12): 1182-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10583923

RESUMEN

OBJECTIVE: This article summarizes the most useful ancillary immunohistochemical and molecular assays for use in the diagnosis of mantle cell lymphoma. DATA SOURCES: The English language literature was surveyed, with an emphasis on recent publications, for articles presenting key advances in the molecular characterization of mantle cell lymphomas and for series of cases testing the utility of molecular diagnostic tests. The authors' series of 26 small B-cell lymphomas, analyzed for the cyclin D1 protein by paraffin immunohistochemistry and for t(11;14) by polymerase chain reaction, is included. CONCLUSIONS: Mantle cell lymphoma, a B-cell lymphoma now recognized in the 1994 Revised European-American Classification of Lymphoid Neoplasms (REAL) classification, is a relatively aggressive lymphoma with a poor prognosis. Its characteristic t(11;14)(q13;q32) translocation has a role in oncogenesis and has been exploited for molecular diagnostic tests, but these tests vary in sensitivity, specificity, and ease of use. Improved immunohistochemical tests are sufficient to confirm the diagnosis in most cases. Conventional cytogenetics and molecular diagnostic tests for t(11;14)-Southern blot and polymerase chain reaction analysis-may be helpful in selected cases, but are laborious or of limited sensitivity. Other methods, such as fluorescence in situ hybridization, need further development to provide faster, more sensitive diagnosis.


Asunto(s)
Linfoma de Células B/diagnóstico , Linfoma de Células B/genética , Citogenética/métodos , Humanos , Inmunofenotipificación , Interfase/genética , Linfoma de Células B/inmunología , Linfoma de Células B/patología , Biología Molecular/métodos
7.
Am J Clin Pathol ; 111(6): 811-6, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10361518

RESUMEN

Patients with chronic viral hepatitis and cirrhosis often have elevated serum alpha-fetoprotein (AFP) values, the causes of which are unclear. We studied 81 patients with chronic hepatitis C and the relationships of serum AFP and alanine aminotransferase (ALT) values, hepatic histologic features, and hepatocyte proliferation activity scores. Twenty-two patients had nil to mild fibrosis, 34 had moderate fibrosis, and 25 had marked fibrosis-cirrhosis. The mean serum AFP value was significantly greater in patients with more fibrosis. Serum ALT values were slightly greater in the marked fibrosis-cirrhosis patient group. The differences in the HAI and in hepatocyte MIB-1 scores were not significant. Among all patients, increasing serum AFP values significantly correlated with increasing ALT values. However, there were no significant correlations with serum ALT or HAI and serum AFP values. There was no association between serum AFP values and immunohistochemical staining for AFP within hepatocytes. These results suggest that elevated serum AFP values are the result of altered hepatocyte-hepatocyte interaction and loss of normal architectural arrangements. The presence of marked fibrosis or cirrhosis, a state of significant altered hepatocyte architecture, may be the underlying cause of increased serum AFP, rather than necrosis or active regeneration.


Asunto(s)
Alanina Transaminasa/sangre , Hepatitis C Crónica/sangre , Hepatitis C Crónica/patología , alfa-Fetoproteínas/análisis , Antígenos Nucleares , División Celular , Hepatitis C Crónica/metabolismo , Humanos , Técnicas para Inmunoenzimas , Antígeno Ki-67 , Proteínas Nucleares/metabolismo
8.
J Hazard Mater ; 66(3): 211-26, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10334822

RESUMEN

The Major Hazard Assessment Unit of the Health and Safety Executive (HSE) provides advice to local planning authorities on land use planning in the vicinity of major hazard sites. For sites with the potential for large scale releases of toxic heavy gases such as chlorine this advice is based on risk levels and is informed by use of the computerised risk assessment tool RISKAT [C. Nussey, M. Pantony, R. Smallwood, HSE's risk assessment tool RISKAT, Major Hazards: Onshore and Offshore, October, 1992]. At present RISKAT uses consequence models for heavy gas dispersion that assume flat terrain. This paper is the first part of a three part paper. Part 1 describes the mathematical basis of TWODEE, the Health and Safety Laboratory's shallow layer model for heavy gas dispersion. The shallow layer approach used by TWODEE is a compromise between the complexity of CFD models and the simpler integral models. Motivated by the low aspect ratio of typical heavy gas clouds, shallow layer models use depth-averaged variables to describe the flow behaviour. This approach is particularly well suited to assess the effect of complex terrain because the downslope buoyancy force is easily included. Entrainment may be incorporated into a shallow layer model by the use of empirical formulae. Part 2 of this paper presents the numerical scheme used to solve the TWODEE mathematical model, and validated against theoretical results. Part 3 compares the results of the TWODEE model with the experimental results taken at Thorney Island [J. McQuaid, B. Roebuck, The dispersion of heavier-than-air gas from a fenced enclosure. Final report to the US Coast Guard on contract with the Health and Safety Executive, Technical Report RPG 1185, Safety Engineering Laboratory, Research and Laboratory Services Division, Broad Lane, Sheffield S3 7HQ, UK, 1985].


Asunto(s)
Gases/farmacocinética , Matemática , Modelos Moleculares , Difusión , Monitoreo del Ambiente/métodos , Gases/análisis , Gravitación , Humanos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Reología , Medición de Riesgo/métodos , Termodinámica
9.
J Hazard Mater ; 66(3): 227-37, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10334823

RESUMEN

Part 1 of this three part paper described the mathematical and physical basis of TWODEE, the Health and Safety Laboratory's shallow layer model for heavy gas dispersion. In this part, the numerical solution method used to simulate the TWODEE mathematical model is developed. The boundary conditions for the leading edge, discussed in part 1, make demanding requirements on the computational scheme used. The flux correction scheme of Zalesak [S.T. Zalesak, Fully multidimensional flux-corrected transport algorithms for fluids, Journal of Computational Physics, 31 (1979) 335-362] is used in TWODEE as this has all the required properties. The TWODEE code is then tested against a number of theoretical and computational benchmark problems.


Asunto(s)
Algoritmos , Gases/farmacocinética , Modelos Moleculares , Análisis Numérico Asistido por Computador , Sesgo , Difusión , Transferencia de Energía , Gases/análisis , Gravitación , Humanos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Reología
10.
J Hazard Mater ; 66(3): 239-61, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10334824

RESUMEN

Part 1 of this three-part paper described the mathematical and physical basis of TWODEE, the Health and Safety Laboratory's shallow layer model for heavy gas dispersion. In part 2, the numerical solution method used to simulate the TWODEE mathematical model was developed; the flux correction scheme of Zalesak [S.T. Zalesak, Fully multidimensional flux-corrected transport algorithms for fluids, Journal of Computational Physics, 31 (1979) 335-362.] was used in TWODEE. This paper compares results of the TWODEE model to the experimental results taken at Thorney Island [J. McQuaid, B. Roebuck, The dispersion of heavier-than-air gas from a fenced enclosure. Final report to the U.S. Coast Guard on contract with the Health and Safety Executive. Technical Report RPG 1185, Safety Engineering Laboratory, Research and Laboratory Services Division, Broad Lane, Sheffield S3 7HQ, UK, 1985.]. There is no evidence to suggest that TWODEE predictions could be improved by changing any of the entrainment parameters from generally accepted values [R.K.S. Hankin, Heavy gas dispersion over complex terrain, PhD thesis, Cambridge University, 1997.]. The TWODEE model was broadly insensitive to the exact values of the entrainment parameters.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Contaminantes Ocupacionales del Aire/farmacocinética , Algoritmos , Monitoreo del Ambiente , Gases/análisis , Gases/farmacocinética , Modelos Moleculares , Análisis Numérico Asistido por Computador , Altitud , Sesgo , Difusión , Monitoreo del Ambiente/métodos , Humanos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Reología , Sensibilidad y Especificidad , Viento
11.
Am J Clin Pathol ; 110(2): 200-9, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9704619

RESUMEN

Some believe endocervical glandular atypia (EGA), purportedly composed of cells that are less atypical than cells of adenocarcinoma in situ (AIS), is a preneoplastic precursor of AIS. We examined 246 neoplastic and nonneoplastic cervical cone biopsy and hysterectomy specimens from 221 patients for lesions composed of glandular cells with less atypia than AIS to define and characterize their association with other glandular processes. To avoid the circular argument of high-grade EGA (dysplasia) vs AIS, we set the minimum degree of AIS cells as the degree of atypia of the cells constituting a moderately differentiated invasive adenocarcinoma. Only 4 endocervical glandular lesions with mild atypia were found, 3 in patients with AIS or invasive endocervical-primary adenocarcinoma and 1 in a patient with invasive endometrial-primary, adenocarcinoma with endocervical extension. There were no lesions with high-grade atypia, nor was there a morphologic spectrum of cells with less atypia than AIS. Of the specimens, 14% had benign endocervical cell changes. The percentage of specimens in each group with benign endocervical cell changes was approximately equal. Although our study is small and retrospective, it suggests that no morphologic evidence exists to support the existence of a spectrum of endocervical glandular changes that culminates in AIS.


Asunto(s)
Adenocarcinoma/patología , Carcinoma in Situ/patología , Cuello del Útero/patología , Lesiones Precancerosas/patología , Neoplasias del Cuello Uterino/patología , Biopsia , Femenino , Humanos , Invasividad Neoplásica/patología
12.
Pediatr Pulmonol ; 26(1): 74-7, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9710282

RESUMEN

Inflammation with infiltrations of eosinophils and mast cells into the walls of airways is considered to increase airway hyperresponsiveness (AHR), which in turn characterizes asthma. We present a child with AHR in whom the clinical course of asthma was related to eosinophilic bronchitis. Our patient was admitted at age 6 months with bronchiolitis and at age 4 years with asthma. Inhaled corticosteroids were begun at age 7 years. At age 8 he developed a meningeal sarcoma. While on chemotherapy, his asthma symptoms resolved and he no longer required prophylactic asthma treatment. After 14 months off all chemotherapy, he again had mild episodic asthma. While receiving chemotherapy for malignancy, he had an admission with a coagulase negative staphylococcal bacteremia. During sputum induction with 4.5% saline, he developed cough, wheeze, and a 20% reduction in peak expiratory flow (220 to 180 L/min) that reversed after treatment with salbutamol. The sputum cell count was 1.7 x 10(6)/ml with 1.1 x 10(6) being neutrophils. Two weeks later and prior to the induction of the second sputum, a 21% increase in FEV1 was recorded after bronchodilator inhalation (82% to 99% of predicted). The second sputum contained 2.7 x 10(6)/ml cells with 1.6 x 10(6)/ml neutrophils. Neither eosinophils nor mast cells were identified in the sputum. A third sputum obtained 14 months after the cessation of chemotherapy showed a sputum cell count of 16 x 10(6)/ml, with 11.6 x 10(6) neutrophils and 0.4 x 10(6) eosinophils; no mast cells were detected. A reversible 15% reduction in FEV1 was detected on hypertonic saline challenge testing. This boy had persistent airway hyperreactivity and reversible airways obstruction on three occasions during and following chemotherapy. When he developed asthma symptoms, his sputum contained neutrophils and eosinophils; while on chemotherapy his sputum did not contain eosinophils and he was symptom-free and off all asthma therapy. One can speculate that chemotherapy for malignancy can induce a remission in asthma symptoms but not AHR, and remission in symptoms is associated with a lack of eosinophilic or mast cell infiltrates in the sputum.


Asunto(s)
Asma/fisiopatología , Neoplasias Meníngeas/tratamiento farmacológico , Sarcoma/tratamiento farmacológico , Asma/complicaciones , Hiperreactividad Bronquial , Bronquitis/fisiopatología , Niño , Eosinófilos , Humanos , Masculino , Mastocitos , Neoplasias Meníngeas/complicaciones , Sarcoma/complicaciones , Esputo/citología
13.
Med J Aust ; 167(4): 195-8, 1997 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-9293265

RESUMEN

OBJECTIVE: To examine general practitioners' (GPs') management of childhood gastroenteritis and their perceptions about barriers to optimal management in the community. DESIGN: Cross-sectional postal survey in which GPs' self-reported practices were assessed by a paediatric gastroenterologist for compliance with published guidelines. SETTING: Hunter region of NSW, mid 1994. PARTICIPANTS: All 422 urban and rural GPs practising in the Hunter region were sent questionnaires; 289 (243 urban and 46 rural) GPs responded. RESULTS: Nearly all GPs (97%) recommended clear fluids in the management of childhood gastroenteritis, with 195 (67%) recommending oral electrolyte solution. Management practices were assessed as: optimal, 170 GPs (59%); acceptable, 33 GPs (11%); inappropriate or potentially dangerous, 38 GPs (13%); and too vague to classify, 48 GPs (17%). Multiple logistic regression analysis showed that better management strategies were associated with being younger and practising in rural areas. GPs perceived the main barriers to effective management of gastroenteritis were: inadequate parenting skills, 131 GPs (45%); lack of parental understanding about the illness, 118 GPs (41%); other social problems, 67 GPs (23%); parental anxiety, 57 GPs (20%); and conflicting advice given by others, 42 GPs (15%). Only 33 GPs (11%) identified the taste and 16 (6%) the cost of oral electrolyte solution as major barriers. CONCLUSIONS: Most GPs reported management of gastroenteritis was acceptable, although not necessarily optimal. GPs need to ensure that parents fully understand the nature of their child's illness and their recommendations for management at home.


Asunto(s)
Medicina Familiar y Comunitaria , Gastroenteritis/terapia , Pautas de la Práctica en Medicina/estadística & datos numéricos , Niño , Estudios Transversales , Fluidoterapia/economía , Humanos , Responsabilidad Parental , Relaciones Profesional-Familia
14.
Am J Orthop (Belle Mead NJ) ; 26(6): 432-40, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9193698

RESUMEN

We describe 2 cases of low-grade central osteosarcoma mimicking fibrous dysplasia and present a review of the literature. These cases illustrate the importance of obtaining a large representative sample of tumor in suspicious lesions, because it may be difficult or impossible to histologically distinguish low-grade central osteosarcoma from a benign lesion with limited samples from a core biopsy or needle aspiration. The treatment of choice for low-grade central osteosarcoma is resection with wide surgical margins or, if limb salvage is not technically feasible, amputation.


Asunto(s)
Neoplasias Femorales/patología , Displasia Fibrosa Ósea/patología , Osteosarcoma/patología , Adolescente , Diagnóstico Diferencial , Femenino , Neoplasias Femorales/cirugía , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Osteosarcoma/cirugía
15.
J Spinal Disord ; 10(6): 467-72, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9438810

RESUMEN

This study evaluated the use of recombinant human bone morphogenetic protein (rhBMP-2) with various types of carrier media, and the effect of rhBMP-2 as an adjunct to autogenous iliac crest bone graft in the canine spinal fusion model. BMP induces mesenchymal cells to differentiate into cartilage and bone. The recent availability of rhBMP-2 has created the opportunity to evaluate this material's properties in augmenting autogenous bone graft in spinal fusion. Currently, the most appropriate type of carrier media for rhBMP-2 is undetermined. Bilateral intertransverse spinal fusions were performed on six canine lumbar spines at L1-L2, L3-L4, and L5-L6, using autogenous posterior iliac crest bone graft at each level, creating a total of 18 segmental fusion sites. All 18 sites were then randomly assigned to one of six fusion methods: autogenous bone graft (ABG) alone, ABG + rhBMP-2, ABG + collagen (Helistat) "sandwich" + rhBMP-2, ABG + collagen (Helistat) morsels + rhBMP-2, ABG + polylactic/glycolic acid sponge (PLGA) sandwich + rhBMP-2, and ABG + open-pore polylactic acid morsels + rhBMP-2. Each material was evaluated for ease of handling and application at the index surgery. The animals underwent computed tomography (CT) scanning of the lumbar fusion sites after 8 weeks. Volumetric measurements of total fusion mass at each level were performed using two-dimensional CT scan slices and a volumetric program supplied by the Siemens Medical System. The animals were killed after imaging studies. The lumbar spine fusion sites were evaluated for integrity of the fusion mass, both visually and with manual mechanical stressing. Crossover of the fusion mass to adjoining levels was also evaluated. Histologic evaluation of all fusion sites was performed. The addition of rhBMP-2 significantly increased bone graft volume as noted on CT scan. Carrier that could be mixed with morselized bone graft offered easier handling and application and all spine segments fused. Polylactic/glycolic acid (PLGA) sites were associated with a greater incidence of voids within the fusion mass. No significant difference in carrier media for rhBMP-2 could be determined. However, PLGA was associated with a higher rate of fusion mass void formation. rhBMP-2, when added to autograft, significantly increased the volume and the maturity of the resulting fusion mass.


Asunto(s)
Proteínas Morfogenéticas Óseas/uso terapéutico , Trasplante Óseo , Osteogénesis/efectos de los fármacos , Fusión Vertebral , Factor de Crecimiento Transformador beta , Animales , Materiales Biocompatibles , Proteína Morfogenética Ósea 2 , Diferenciación Celular/efectos de los fármacos , Colágeno/administración & dosificación , Perros , Portadores de Fármacos , Ilion/trasplante , Ácido Láctico/administración & dosificación , Mesodermo/efectos de los fármacos , Ácido Poliglicólico/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Tapones Quirúrgicos de Gaza
17.
Am J Clin Pathol ; 103(4): 409-14, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7726136

RESUMEN

Ploidy analysis of hydropic placentas is used in conjunction with morphology and clinical data to classify hydatidiform moles and hydropic abortuses. In most studies, ploidy has been assessed by flow cytometry (FCM). To validate image cytometry (ICM) as a method to determine ploidy in this setting, the authors used both FCM and ICM to study 19 hydropic placentas in which cytogenetic analysis was available. Nuclear suspensions from paraffin-embedded tissue were used for both ICM and FCM. Image cytometry of tissue sections was performed in some cases. Image cytometry and FCM were concordant in all 19 cases, but discordant with cytogenetics in 2 of 19 cases. Two hydropic abortuses (HA) with a diploid karyotype were triploid and tetraploid, respectively, by both ICM and FCM, which suggested that the cultured tissue was not representative. DNA indices were most accurate when an internal diploid control was used as the reference. In ICM, higher resolution was achieved by analyzing cell suspensions rather than tissue sections. This study shows that ICM is a valid method of determining ploidy of hydropic placentas and partial hydatidiform moles in archival tissue.


Asunto(s)
Citogenética/métodos , Citometría de Flujo , Mola Hidatiforme/genética , Hidropesía Fetal/genética , Procesamiento de Imagen Asistido por Computador , Ploidias , Femenino , Humanos , Cariotipificación , Embarazo
18.
J Paediatr Child Health ; 30(3): 253-6, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8074912

RESUMEN

The aim of this study was to investigate the association between headache and asthma, bronchodilators and atopy in school children. A cross-sectional survey of all primary school children was conducted in two towns near Newcastle, New South Wales, Australia; one in the vicinity of two coal-fired power stations, the other free of outdoor industrial air pollution. The main outcome measures were frequent headache, wheezing, bronchial reactivity, use of bronchodilators and atopy. Eight hundred and fifty-one primary school children aged 5-12 years participated (92% response rate). Twenty-three per cent of the children were reported to have had a history of frequent headache. Crude odds ratios indicated that the odds of frequent headache was significantly higher in children with asthma and atopy and where there was a smoker in the home, but that there was no association between frequent headache and use of bronchodilators or the sex of the child or socio-economic status measured as father's occupation. Stepwise logistic regression with frequent headache as the outcome of interest showed that, after adjusting for age and smoking in the home, the odds ratio for asthma (defined as current wheeze) was 3.24 (95% confidence interval [CI] 2.19-4.77). The similarly adjusted odds ratio for asthma defined as bronchial hyperreactivity (BHR) was 1.60 (95% CI 1.09-2.37). Atopy was not statistically significantly associated with headache for either model. Asthma (defined as wheeze or BHR) is an independent risk factor for frequent headache. The relationship between headache and asthma is an association with bronchial hyperresponsiveness rather than atopy.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Asma/complicaciones , Hiperreactividad Bronquial/complicaciones , Cefalea/etiología , Hipersensibilidad Inmediata/complicaciones , Vigilancia de la Población , Ruidos Respiratorios , Factores de Edad , Asma/tratamiento farmacológico , Asma/epidemiología , Asma/fisiopatología , Hiperreactividad Bronquial/epidemiología , Hiperreactividad Bronquial/fisiopatología , Broncodilatadores/uso terapéutico , Niño , Preescolar , Estudios Transversales , Femenino , Cefalea/epidemiología , Encuestas Epidemiológicas , Humanos , Hipersensibilidad Inmediata/epidemiología , Modelos Logísticos , Masculino , Nueva Gales del Sur/epidemiología , Oportunidad Relativa , Prevalencia , Ruidos Respiratorios/fisiopatología , Factores de Riesgo , Contaminación por Humo de Tabaco/efectos adversos
19.
J Epidemiol Community Health ; 47(4): 282-6, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8228762

RESUMEN

STUDY OBJECTIVE: In a previous study a higher than expected prevalence of asthma was found in Lake Munmorah, a coastal town near two power stations, compared with another coastal control town. This study aimed to compare atopy, bronchial hyperreactivity, and reported symptoms of asthma in the power station town and a second control area with greater socioeconomic similarity. DESIGN: A cross sectional survey was undertaken. SETTINGS: Lake Munmorah, a coastal town near two power stations, and Dungog, a country town in the Hunter Valley, NSW, Australia. PARTICIPANTS: All children attending kindergarten to year 6 at all schools in the two towns were invited to participate in 1990. The response rates for the questionnaire for reported symptoms and associated demographic data were 92% in Lake Munmorah and 93% in Dungog, with 84% and 90% of children respectively being measured for lung function, atopy, and bronchial reactivity. There were 419 boys and 432 girls aged 5 to 12 years. MEASUREMENTS AND MAIN RESULTS: Main outcome measures were current wheeze and bronchial hyper-reactivity, defined as a fall in forced expiratory volume in 1 second (FEV1) or peak expiratory flow (PEF) of 20% or more. Current wheeze was reported in 24.8% of the Lake Munmorah children compared with 14.6% of the Dungog children. Bronchial hyper-reactivity was similar for both groups--25.2% in Lake Munmorah and 22.3% in Dungog. The mean baseline FEV1 was lower in Lake Munmorah than in Dungog (p < 0.001). Dungog children were more likely to have positive skin test to house dust mite (Dungog 27.0%, Lake Munmorah 20.2%, p = 0.028) but there were no other differences in skin test atopy in the two towns. After adjusting for age, gender, any smoker in the house, and positive dust mite skin test, the odds of current wheeze in Lake Munmorah compared with Dungog was 2.16 (95% confidence interval 1.45, 3.15). CONCLUSIONS: Baseline lung function was lower and reported symptoms of asthma were higher in the power station town, but bronchial hyper-reactivity and skin test defined atopy were similar in the two communities. These results are consistent with the previous study and confirm the increased presence of reported symptomatic illness in the town near power stations.


Asunto(s)
Asma/etiología , Hiperreactividad Bronquial/etiología , Contaminación Ambiental/efectos adversos , Centrales Eléctricas , Ruidos Respiratorios/etiología , Asma/epidemiología , Hiperreactividad Bronquial/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Nueva Gales del Sur/epidemiología , Prevalencia
20.
Orthop Rev ; 21(8): 963-70, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1523011

RESUMEN

The incidence of malignant soft-tissue sarcomas in the general population is approximately 1.4 per 100,000. Approximately 2% of all cancer deaths are attributable to these tumors. Presented is a case history of a soft-tissue malignant neoplasm that was originally thought to be an interdigital neuroma and that eventually required a modified Chopart's amputation. A review of the literature is presented on other soft-tissue malignant tumors that have an affinity for the foot and ankle. The intention of presenting this case is to caution physicians that malignant lesions can simulate a benign process and should always be considered in the differential diagnosis of any foot mass.


Asunto(s)
Enfermedades del Pie/diagnóstico , Melanoma/diagnóstico , Sarcoma/diagnóstico , Neoplasias de los Tejidos Blandos/diagnóstico , Adolescente , Amputación Quirúrgica , Diagnóstico Diferencial , Femenino , Enfermedades del Pie/patología , Enfermedades del Pie/cirugía , Humanos , Imagen por Resonancia Magnética , Melanoma/patología , Melanoma/cirugía , Rango del Movimiento Articular , Sarcoma/patología , Sarcoma/cirugía , Neoplasias de los Tejidos Blandos/patología , Neoplasias de los Tejidos Blandos/cirugía , Tomografía Computarizada por Rayos X
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