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1.
BJOG ; 119(7): 800-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22571746

RESUMEN

OBJECTIVE: To assess the efficacy and morbidity and mortality of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in recurrent epithelial ovarian cancer (EOC). DESIGN: A retrospective study conducted using information extracted from a multi-institutional prospective database on peritoneal surface malignancies (PSMs). Setting Four Italian centres specializing in locoregional treatment of PSM. POPULATION: Patients with recurrent EOC. METHODS: Fifty-six patients underwent 57 combined procedures. CRS was performed using peritonectomy procedures and HIPEC using the closed-abdomen technique with cisplatin and doxorubicin or cisplatin and mitomycin-C. MAIN OUTCOME MEASURES: Overall survival (OS), progression-free survival (PFS), morbidity and mortality rates. RESULTS: The median age of the patients was 55.2 years (range 30-75 years). The median peritoneal cancer index was 15.2 (range 4-30). Forty-seven patients had microscopic residual disease (completeness of cytoreduction, CC-0), seven had residual disease ≤2.5 mm (CC-1) and one had residual disease >2.5 mm (CC>2). Major complications occurred in 15 patients (26.3%), and procedure-related mortality occurred in three patients (5.3%). The median follow-up time was 23.1 months. The median OS and PFS were 25.7 (95% CI 20.3-31.0) and 10.8 (95% CI 5.4-16.2) months, respectively. The 5-year OS and PFS were 23% and 7%, respectively. Independent prognostic factors affecting OS according to the multivariate analysis were Eastern Cooperative Oncology Group performance status, preoperative serum albumin, and completeness of cytoreduction. CONCLUSIONS: Patients with recurrent EOC treated with CRS and HIPEC showed promising results in terms of outcome. The combined treatment strategy could benefit subsets of patients wider than that defined for conventional secondary debulking surgery without HIPEC. These data warrant further evaluation in randomised clinical trials.


Asunto(s)
Antineoplásicos/uso terapéutico , Hipertermia Inducida , Recurrencia Local de Neoplasia/terapia , Neoplasias Glandulares y Epiteliales/terapia , Neoplasias Ováricas/terapia , Neoplasias Peritoneales/terapia , Peritoneo/cirugía , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Epitelial de Ovario , Cisplatino/uso terapéutico , Terapia Combinada , Doxorrubicina/uso terapéutico , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Infusiones Parenterales , Persona de Mediana Edad , Mitomicina/uso terapéutico , Análisis Multivariante , Recurrencia Local de Neoplasia/mortalidad , Neoplasias Glandulares y Epiteliales/mortalidad , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Neoplasias Peritoneales/mortalidad , Neoplasias Peritoneales/secundario , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
2.
Med Eng Phys ; 34(9): 1339-55, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22472525

RESUMEN

The ossicular chain of the human middle ear has a key role in sound conduction since it transfers vibrations from the tympanic membrane to the cochlea, connecting the outer and the inner part of the hearing organ. This study reports firstly a description of the main anatomical features of the middle ear to introduce a detailed survey of its biomechanics, focused on model development, with a collection of geometric, inertial and mechanical/material parameters. The joint issues are particularly discussed from the perspective of developing a model of the middle ear both explanatory and predictive. Such a survey underlines the remarkable dispersion of data, due also to the lack of a standardization of the experimental techniques and conditions. Subsequently, a 3D multi-body model of the ossicular chain and other structures of the middle ear is described. Such an approach is justified as the ossicles were proven to behave as rigid bodies in the human hearing range and was preferred to the more widely used finite element one as it simplifies the model development and improves joint modeling. The displacement of the umbo (a reference point of the tympanic membrane) in the 0.3-6kHz frequency range was defined as input of the model, while the stapes footplate displacement as output. A parameter identification procedure was used to find parameter values for reproducing experimental and numerical reference curves taken from the literature. This simple model might represent a valid alternative to more complex models and might provide a useful tool to simulate pathological/post-surgical/post-traumatic conditions and evaluate ossicular replacement prostheses.


Asunto(s)
Osículos del Oído/anatomía & histología , Modelos Anatómicos , Fenómenos Biomecánicos , Calibración , Osículos del Oído/fisiología , Análisis de Elementos Finitos , Humanos , Ligamentos/anatomía & histología , Ligamentos/fisiología , Movimiento
3.
J Biomech ; 44(13): 2418-26, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21767843

RESUMEN

Abdominal aortic aneurysm (AAA) is a cardiovascular disease with high incidence among elderly population. Biomechanical computational analyses can provide fundamental insights into AAA pathogenesis and clinical management, but modeling should be sufficiently accurate. Several constitutive models of the AAA wall are present in the literature, and some of them seem to well describe the experimental behavior of the aneurysmatic human aorta. In this work we compare a two (2FF) and a four (4FF) fiber families constitutive models of the AAA wall. Both these models satisfactorily fit literature data from biaxial tests on the aneurysmatic tissue. To investigate the peculiar characteristics of these models, we considered the problem of AAA inflation, and solved it by implementing the constitutive equations in a finite element code. A 20% axial stretch was imposed to the aneurysm ends, to simulate the physiological condition. Although fitted on the same dataset, the two material models lead to considerably different outcomes. In particular, adopting a 4FF strain energy function (SEF), an increase of the circumferential stress values can be observed, while higher axial stresses are recorded for the 2FF model. These differences can be attributed to the intrinsic characteristics of the SEFs and to the effective stress field, with respect to the one experienced in biaxial experimental tests on which the fitting is based. In fact the two SEFs appear similar within the region of the stress-strain experimental data, but become different outside it, as in case of aneurysms, due to the effects of the data extrapolation process. It is suggested that experimental data should be obtained for conditions similar to those of the application for which they are intended.


Asunto(s)
Aneurisma de la Aorta Abdominal/patología , Modelos Cardiovasculares , Aneurisma de la Aorta Abdominal/fisiopatología , Fenómenos Biomecánicos , Simulación por Computador , Humanos , Cómputos Matemáticos
4.
J Biomech ; 44(7): 1219-36, 2011 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-21376326

RESUMEN

The tympanic membrane is a key component of the human auditory apparatus which is a complex biomechanical system, devoted to sound reception and perception. Over the past 30 years, various bioengineering approaches have been applied to the ear modeling and particularly to the middle part. The tympanic membrane, included in the middle ear, transfers sound waves into mechanical vibration from the ear canal into the middle ear. Changes in structure and mechanical properties of the tympanic membrane due to middle ear diseases or damages can deteriorate sound transmission. An accurate model of the tympanic membrane, which simulates the acoustic-mechanical transmission, could improve clinical surgical intervention. In this paper a detailed survey of the biomechanics and the modeling of the tympanic membrane focusing on the finite element method is conduced. Eight selected models are evaluated and compared deducing the main features and most design parameters from published models, mainly focusing on geometric, constraint and material aspects. Non-specified parameters are replaced with the most commonly employed values. Our simulation results (in terms of modal frequencies and umbo displacement), compared with published numerical and experimental results, show a good agreement even if some scattering appears to indicate the need of further investigation and experimental validation.


Asunto(s)
Membrana Timpánica/fisiología , Acústica , Fenómenos Biomecánicos , Cadáver , Calibración , Simulación por Computador , Oído Medio/fisiología , Elasticidad , Audición , Humanos , Modelos Anatómicos , Modelos Biológicos , Presión , Sonido , Vibración
5.
Int Arch Allergy Immunol ; 154(3): 195-206, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20861641

RESUMEN

BACKGROUND: Ascaris lumbricoides induces a Th2 response and specific IgE synthesis in humans. This confers antiparasite immunity but could modify the natural history of allergic diseases in the tropics, justifying the study of its allergenic composition. We analyzed the allergenic properties of Ascaris tropomyosin and the frequency of sensitization in subjects exposed to the parasite. METHODS: cDNA was obtained by reverse transcription PCR, cloned into pQE30-UA and purified as a 6× His-tagged protein. Equivalence with its natural counterpart was analyzed by cross-inhibition and liquid chromatography-tandem mass spectrometry. Specific IgE was measured by ELISA in 175 asthmatics and 170 nonasthmatics naturally exposed to the parasite and sensitized to the Ascaris extract. RESULTS: The cDNA encoded 287 residues with high sequence identity with other invertebrate tropomyosins. The 40-kDa protein was recognized by human serum and affinity-purified anti-rBlo t 10 IgE. Specific IgE to tropomyosin could represent approximately 50% of the total IgE response to the extract. Ascaris tropomyosin induced wheal and flare in skin prick tests and histamine release from basophils. Although the prevalence of IgE to Ascaris tropomyosin was higher in asthmatic patients, logistic regression analysis suggested that this result was biased by sensitization to mites. CONCLUSIONS: A. lumbricoides tropomyosin (Asc l 3) is a new allergen that binds specific IgE, induces mediator release from effector cells and is cross-reactive to mite tropomyosins. IgE reactivity to this allergen is very frequent in both asthmatic and normal subjects sensitized to Ascaris extract. The potential role of Ascaris tropomyosin in asthma pathogenesis in tropical regions should be further investigated.


Asunto(s)
Alérgenos/inmunología , Ascaris lumbricoides/inmunología , Asma/inmunología , Inmunoglobulina E/sangre , Tropomiosina/inmunología , Adolescente , Adulto , Alérgenos/genética , Secuencia de Aminoácidos , Animales , Ascaris lumbricoides/metabolismo , Niño , Colombia , Reacciones Cruzadas , Femenino , Humanos , Hipersensibilidad/inmunología , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Ácaros/inmunología , Ácaros/metabolismo , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Pruebas Cutáneas , Clima Tropical , Tropomiosina/genética , Adulto Joven
6.
Eur J Surg Oncol ; 37(1): 4-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21112721

RESUMEN

Favorable oncological outcomes have been reported in several trials with the introduction of Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the treatment of Advanced Epithelial Ovarian Cancer (EOC). However most of the studies testing the combined approach are observational and have been conducted in inhomogeneous series so that the evidence supporting the performance of this combined treatment is still poor. Median Overall and Disease Free Survivals of up to 64 months and 57 months, respectively have been reported. Although a rate of morbidity of up to 40% has been observed in some series the CRS + HIPEC continues to gain an increased popularity. Several prospective randomized trials are ongoing using the procedure in various time points of the disease. In this review several issues such as the impact of cytoreduction and residual disease (RD) on outcomes as well as the role of HIPEC will be updated from the literature evidence. Some controversial points HIPEC related will also be discussed. Recent experiences regarding the introduction of a more aggressive surgical approach to upper abdomen to resect peritoneal carcinomatosis (PC) allowed increased rates of optimal cytoreduction and has demonstrated an apparent better outcome. This evidence associated with the positive results phase III trial testing normothermic intraperitoneal as first-line chemotherapy is guiding some investigators to propose the CRS + HIPEC in the primary setting. Several prospective phase II and III trials have recently been launched to validate the role of the combined treatment in various time points of disease natural evolution.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma Epitelial de Ovario , Terapia Combinada , Femenino , Humanos , Hipertermia Inducida , Infusiones Parenterales , Neoplasias Glandulares y Epiteliales/cirugía , Neoplasias Ováricas/cirugía , Nivel de Atención
7.
Acta Trop ; 117(3): 189-95, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21172297

RESUMEN

We evaluated the effect of Ascaris lumbricoides on Giardia duodenalis infection and TH1/TH2 type immune mechanisms toward this parasite in 251 rural parasitized and 70 urban non-parasitized school children. The children were classified according to light (0-5000 eggs/g faeces) or moderate (>5001-50,000 eggs/g faeces) A. lumbricoides infection. Anti G. duodenalis skin hyper-reactivity, IgE, IgG, IL-13, IFN γ, IL6 and IL-10 levels were compared among G. duodenalis infected and non-infected children according to light or moderate A. lumbricoides infection. It was found that 62% of the A. lumbricoides moderately infected children were co-infected by G. duodenalis compared to 45% of the lightly infected group. After treatment, 42% of the A. lumbricoides moderately group were infected with G. duodenalis compared to 11% of their lightly counterparts, being A. lumbricoides IL-10 levels higher (p<0.0001) in the moderately infected group. In the A. lumbricoides lightly parasitized children, G. duodenalis infection was associated to a significant increase (p<0.005) of the levels of G. duodenalis IL-13, IFN-γ, IL-6, IgE, IgG and skin test hyper reactivity. In contrast, there was no effect of G. duodenalis infection in the elevation of these parameters among the A. lumbricoides moderately parasitized group, being those levels similarly lower as those observed in the control group. Inverse correlations were found between the levels of anti G duodenalis antibodies, skin test hyper-reactivity and cytokines with the intensity of A. lumbricoides infection (p>0.0001) and A. lumbricoides IL-10 levels (p>0.0001), suggesting that co-infection with A. lumbricoides may affect both TH1 and TH2 type immunity against G. duodenalis that may play an important role in the susceptibility to the infection after chemotherapy in children from endemic areas.


Asunto(s)
Ascariasis/inmunología , Giardiasis/inmunología , Inmunomodulación , Animales , Anticuerpos/inmunología , Ascariasis/complicaciones , Ascariasis/epidemiología , Ascariasis/parasitología , Ascaris lumbricoides/fisiología , Estudios de Casos y Controles , Niño , Citocinas/inmunología , Giardia lamblia/fisiología , Giardiasis/complicaciones , Giardiasis/epidemiología , Giardiasis/parasitología , Interacciones Huésped-Patógeno , Humanos , Hipersensibilidad/inmunología , Inmunoglobulinas/inmunología , Recuento de Huevos de Parásitos , Población Rural , Índice de Severidad de la Enfermedad , Pruebas Cutáneas , Balance Th1 - Th2 , Venezuela/epidemiología
8.
Acta Trop ; 103(3): 231-41, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17698018

RESUMEN

Asthma and other respiratory diseases have increased in the last years among Venezuelan children from helminthic endemic areas where the infection by Ascaris lumbricoides has been associated to bronchial airway inflammation in parasitized individuals. The aim of this work was to investigate the possible associations between the development of bronchial hyper reactivity and the immune response against A. lumbricoides in urban and rural children. We evaluated 470 school children from rural and urban communities. Pulmonary function tests were performed and >or=20% PC(20) changes were considered as a positive diagnostic of bronchial hyper reactivity. The prevalence and intensity of A. lumbricoides infection was determined by faecal examination. Specific serum IgE levels using a modified ELISA and skin prick tests against A. lumbricoides and the common allergen Dermatophagoides pteronyssinus were done. The number of circulating lymphocyte sub populations was determined by flow cytometry analysis. In rural children, bronchial hyper reactivity was associated with increased specific levels of anti-A. lumbricoides IgE (p<0.0001) and skin test positivity for A. lumbricoides (p<0.0001). The percentage of FEV1 predictive values correlated inversely (p<0.0001) with anti-A. lumbricoides IgE levels. Elevated numbers of circulating CD3+CD4+ and CD20+CD23+ cells were found in rural children with bronchial hyper reactivity compared to their asymptomatic counterparts. They correlated positively with anti-A. lumbricoides IgE levels (p<0.005 and <0.0001, respectively). In contrast, in urban children, bronchial hyper reactivity was associated with elevated anti-D. pteronyssinus IgE levels (p=0. 0089), skin hyper reactivity towards this aero allergen (p=0.003) and to an increase in the number of CD3+CD8+ (p<0.0001). Our results suggest that the IgE response against A. lumbricoides infection may be involved in the development of bronchial hyper reactivity among rural children from endemic areas and also that improved hygienic conditions in the urban environment is associated with increased responses to airborne allergens.


Asunto(s)
Ascariasis/epidemiología , Ascariasis/inmunología , Ascaris lumbricoides , Hiperreactividad Bronquial/parasitología , Enfermedades Endémicas , Animales , Ascariasis/complicaciones , Subgrupos de Linfocitos B , Hiperreactividad Bronquial/diagnóstico , Niño , Ambiente , Femenino , Humanos , Hipersensibilidad/diagnóstico , Inmunoglobulina E/sangre , Recuento de Linfocitos , Masculino , Prevalencia , Pruebas de Función Respiratoria , Enfermedades de la Piel/complicaciones , Enfermedades de la Piel/diagnóstico , Pruebas Cutáneas , Subgrupos de Linfocitos T , Venezuela/epidemiología
10.
Int Surg ; 90(3 Suppl): S21-3, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16463943

RESUMEN

Using mesh or a synthetic prosthesis during tension-free inguinal hernia repair has been shown to be safe and effective. We compared the final outcome in treating inguinal hernia in 45 patients using three different prosthetic materials: 15 patients underwent tension-free inguinal hernia repair using Prolene (polypropylene) mesh, 15 using Vypro (polyglactin and polypropylene) mesh, and 15 with Surgisis-a new bioactive material derived from porcine small intestinal submucosa. The aim of this study was to evaluate the safety and efficacy of tension-free inguinal repair using Surgisis, comparing it with conventional prosthetic materials. From January 2003 to December 2003, 45 male patients underwent Lichtenstein inguinal hernia repair. Median follow-up was 12 months, with a range of 1-16 months. Each patient underwent ultrasound evaluation of the inguinal region 1 month after surgery. All the procedures were completed under local anesthesia. There were no intraoperative complications, and all patients were discharged home the same day of surgery. No recurrent hernias and wound infections were observed in our post-operative follow-up period. Postoperative pain (visual analog score) and discomfort were lower in patients with Surgisis mesh. There was no statistically significant difference between the groups in terms of overall early and late complications; however, there was a tendency toward a higher incidence of pain and discomfort in Vypro and Prolene group. The median time to full recovery was significantly shorter in the Surgisis group. Surgisis mesh seems to be a promising new prosthetic material for hernia repair. Long-term follow-up is necessary to confirm these preliminary results.


Asunto(s)
Hernia Inguinal/cirugía , Mallas Quirúrgicas , Adulto , Anciano , Animales , Distribución de Chi-Cuadrado , Humanos , Mucosa Intestinal , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/epidemiología , Poliglactina 910 , Polipropilenos , Porcinos , Resultado del Tratamiento
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