Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Pediatr Surg ; 34(1): 56-62, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37406675

RESUMO

OBJECTIVE: This article tests the protective effect of a commercially available mixture of hyaluronic acid, chondroitin sulfate, and poloxamer 407 on the damage caused by the exposure of esophageal mucosa to button batteries in an animal model. METHODS: Experimental study. Sixty porcine esophageal samples were distributed in three groups: control (CG), exposure (EG), and exposure-protection (EPG). In EG and EPG, one CR2032 button battery per sample was inserted, both were subdivided into 2-, 4-, 6-, and 24-hour exposure subgroups, with subsequent battery removal. EPG samples were irrigated with the solution 1 hour after battery exposure. Esophageal pH and final voltage of the battery were measured. RESULTS: pH in CG remained stable. No significant differences in pH at 1 hour were found between EG and EPG. In EPG, the pH of the mucosa exposed to the anode was lower than in GE at 2 hours (12.44 vs. 11.89, p = 0.203) and 4 hours (13.78 vs. 11.77, p < 0.0001). In the cathode pH was significantly higher in EG at 2 hours (2.5 vs. 4.11, p < 0.0001), 4 hours (2.33 vs. 4.78, p < 0.0001), and 6 hours (2.17 vs. 2.91, p < 0.0001). Significant voltage reduction at 1 hour was found in EG compared to EPG (0.48 vs. 1.08 V, p = 0.004). CONCLUSION: Exposure to hyaluronic acid solution buffers the acidification on the side exposed to the cathode and basification on the anode. This effect can be maintained up to 3 to 5 hours, even after stopping its application. Our results suggest that a solution containing hyaluronic acid could be used as an esophageal protector after accidental ingestion of button batteries.


Assuntos
Corpos Estranhos , Ácido Hialurônico , Animais , Suínos , Esôfago/cirurgia , Fontes de Energia Elétrica
2.
ScientificWorldJournal ; 2013: 402196, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23843734

RESUMO

This paper presents the next step in the evolution of multi-sensor wireless network systems in the early automatic detection of forest fires. This network allows remote monitoring of each of the locations as well as communication between each of the sensors and with the control stations. The result is an increased coverage area, with quicker and safer responses. To determine the presence of a forest wildfire, the system employs decision fusion in thermal imaging, which can exploit various expected characteristics of a real fire, including short-term persistence and long-term increases over time. Results from testing in the laboratory and in a real environment are presented to authenticate and verify the accuracy of the operation of the proposed system. The system performance is gauged by the number of alarms and the time to the first alarm (corresponding to a real fire), for different probability of false alarm (PFA). The necessity of including decision fusion is thereby demonstrated.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Monitoramento Ambiental/instrumentação , Incêndios , Interpretação de Imagem Assistida por Computador/instrumentação , Termografia/instrumentação , Transdutores , Tecnologia sem Fio/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos
3.
Cir Pediatr ; 36(2): 78-82, 2023 Apr 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37093117

RESUMO

OBJECTIVE: To assess the efficacy of the endourological treatment of ectopic ureterocele in children in a large series and with a long-term follow-up. MATERIALS AND METHODS: A retrospective, descriptive study of patients with ectopic ureterocele who had undergone surgery in our institution in the last 15 years was carried out. All patients were treated using an endourological approach, both for ureterocele and postoperative vesicoureteral reflux (VUR). RESULTS: 40 patients were treated -55% with left involvement and 5% with bilateral involvement. Mean age at diagnosis was 4.97 months, with diagnosis being established prenatally in 54.1% of cases. In all patients but one, endourological puncture of the ureterocele was conducted. Mean age at surgery was 6.96 months (0-1.11). Surgery was performed on an outpatient basis in 94.9% of patients. No perioperative complications were recorded. In the last 30 patients, preoperative voiding cystourethrography was not carried out. 72.5% of patients had postoperative VUR (44.8% into the upper pyelon, 10.3% into the lower pyelon, 17.2% into both, 6.9% into the contralateral system, and 20.7% into the bilateral system), but it was resolved with a single endoscopic procedure in 48.1% of cases (65% of patients were healed with two procedures). VUR was not endoscopically resolved in 3 patients who required ureteral re-implantation. 6 patients required heminephrectomy (n=3) or nephrectomy (n=3) as a result of functional impairment and infections. CONCLUSION: The endourological treatment of ectopic ureterocele is a little aggressive and little invasive technique that allows the obstruction to be resolved on an outpatient basis, which means bladder surgery -if required- can be performed outside the neonatal period.


OBJETIVO: Evaluar la eficacia del tratamiento endourológico del ureterocele ectópico en niños en una serie amplia y con seguimiento a largo plazo. MATERIAL Y METODOS: Estudio retrospectivo descriptivo de los pacientes con ureterocele ectópico intervenidos en nuestro centro en los últimos 15 años. Todos los pacientes se tratan por vía endourológica, tanto el ureterocele como el reflujo vesicoureteral (RVU) postoperatorio. RESULTADOS: Se trataron 40 pacientes, 55% eran izquierdos y 5% bilaterales. La edad media al diagnóstico fue de 4,97 meses siendo de diagnóstico prenatal el 54,1%. En todos los pacientes menos uno se realizó una punción endourológica del ureterocele. La edad media en el momento de la cirugía era de 6,96 meses (0-1,11). La cirugía fue ambulante en un 94,9% de los pacientes. No se registraron complicaciones perioperatorias. En los últimos 30 pacientes no se realizó cistouretrografía miccional preoperatoria. Un 72,5% de los pacientes presentaron RVU postoperatorio (44,8% a pielón superior, 10,3% a pielón inferior, 17,2% a ambos, 6,9% al sistema contralateral y 20,7% bilateral), pero este se resolvió con un único procedimiento endoscópico en un 48,1% de los casos (curación del 65% de los pacientes con dos procedimientos). El RVU no se resolvió de forma endoscópica en 3 pacientes que requirieron un reimplante ureteral. Seis pacientes precisaron heminefrectomía (n= 3) o nefrectomía (n= 3) por anulación funcional e infecciones. CONCLUSION: El tratamiento endourológico del ureterocele ectópico es una técnica poco agresiva invasiva que consigue la resolución de la obstrucción de forma ambulante permitiendo diferir la cirugía vesical (si fuera necesaria) fuera del periodo neonatal.


Assuntos
Ureter , Ureterocele , Refluxo Vesicoureteral , Criança , Recém-Nascido , Humanos , Lactente , Ureterocele/complicações , Ureterocele/diagnóstico , Ureterocele/cirurgia , Estudos Retrospectivos , Endoscopia/efeitos adversos , Procedimentos Cirúrgicos Urológicos , Resultado do Tratamento , Refluxo Vesicoureteral/complicações
4.
Cir Pediatr ; 36(3): 140-143, 2023 Jul 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37417219

RESUMO

Pediatric pneumonectomies are exceptional nowadays, being reserved for cases with destroyed lungs with frequent exacerbations and reinfections and only two cases of thoracoscopic pneumonectomy have been previously published. We present the case of a 4-year-old patient with no relevant history who developed complete atelectasis of the left lung (LL) after influenza A pneumonia, followed by secondary recurrent infections. A year later a diagnostic bronchoscopy without alterations was performed. A complete loss of volume and hypoperfusion of the LL (right lung perfusion 95%, LL perfusion: 5%) with bronchiectasis and hyperinsufflation and herniation of the right lung into the left hemithorax was observed in a pulmonary perfusion SPECT-CT. After unsuccessful conservative management and recurrent infections a pneumonectomy was indicated. The pneumonectomy was performed through a five-port thoracoscopy. The dissection of the hilum was made using hook electrocautery and sealing device. The left main bronchus was sectioned with an endostapler. There were no intraoperative complications. An endothoracic drain was removed the first postoperative day. The patient was discharged on the fourth postoperative day. The patient has not presented any complications 10 months after surgery. Although pneumonectomy is an exceptional surgery in children, it can be performed by minimally invasive surgery with success and safety in centers with extensive experience in pediatric thoracoscopic surgery.


Hoy en día, las neumonectomías pediátricas son algo excepcional. El procedimiento se reserva para aquellos casos en los que los pulmones están destruidos y presentan exacerbaciones y reinfecciones frecuentes, con tan solo dos casos de neumonectomía toracoscópica publicados hasta la fecha. Presentamos el caso de un paciente de 4 años sin antecedentes de interés que desarrolló atelectasia completa del pulmón izquierdo (PI) tras neumonía por gripe A, seguido de infecciones secundarias recurrentes. Un año después, se le practicó broncoscopia diagnóstica, sin que esta mostrara alteraciones significativas. Tras realizársele un SPECT-CT de perfusión pulmonar, se evidenció pérdida completa de volumen e hipoperfusión del PI (perfusión del pulmón derecho: 95%; perfusión del pulmón izquierdo: 5%), con bronquiectasia e hiperinsuflación y herniación del pulmón derecho hacia el hemitórax izquierdo. Tras fracasar el manejo conservador y registrarse infecciones recurrentes, se estableció la indicación de neumonectomía. La neumonectomía se llevó a cabo mediante toracoscopia por cinco puertos. La disección del hilio se realizó mediante gancho de electrocoagulación y dispositivo de sellado. El bronquio principal izquierdo se seccionó con endograpadora. No se registraron complicaciones intraoperatorias. El drenaje endotorácico se retiró al día siguiente de la intervención, mientras que el paciente fue dado de alta a los cuatro días, sin que haya presentado complicaciones transcurridos 10 meses desde la cirugía. Aunque la neumonectomía es una intervención excepcional en niños, puede llevarse a cabo de manera exitosa y segura por cirugía mínimamente invasiva en centros con amplia experiencia en cirugía toracoscópica pediátrica.


Assuntos
Pneumonectomia , Pneumonia Viral , Humanos , Criança , Pré-Escolar , Reinfecção , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Toracoscopia
5.
Balkan J Med Genet ; 15(2): 7-14, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24052726

RESUMO

This study reports on variations at the mitochondrial DNA (mtDNA) hypervariable region 1 (HVR-1) and at seven Y-chromosome microsatellites in an African-American population sample from Chicago, IL, USA. Our results support the hypothesis that the population studied had undergone a European male-biased gene flow. We show that comparisons of intra-and inter-population diversity parameters between African-Americans, Europeans and Africans may help detect sex-biased gene flow, providing a complement to quantitative methods to estimate genetic admixture.

6.
Mol Ther Methods Clin Dev ; 26: 207-223, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-35859694

RESUMO

Autologous cell immunotherapy using B cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR)-T cells is an effective novel treatment for multiple myeloma (MM). This therapy has only been used for relapsed and refractory patients, at which stage the endogenous T cells used to produce the CAR-T cells are affected by the immunosuppressive nature of advanced MM and/or side effects of previous therapies. An alternative pool of "fitter" T cells is found in leukocytoapheresis products that are routinely collected to obtain hematopoietic progenitor cells for autologous stem cell transplantation (ASCT) early in the treatment of MM. However, to mobilize the progenitor cells, patients are dosed with granulocyte colony-stimulating factor (G-CSF), which is reported to adversely affect T cell proliferation, function, and differentiation. Here, we aimed to first establish whether G-CSF treatment negatively influences T cell phenotype and to ascertain whether previous exposure of T cells to G-CSF is deleterious for anti-BCMA CAR-T cells. We observed that G-CSF had a minimal impact on T cell phenotype when added in vitro or administered to patients. Moreover, we found that CAR-T cell fitness and anti-tumor activity were unaffected when generated from G-CSF-exposed T cells. Overall, we showed that ASCT apheresis products are a suitable source of T cells for anti-BCMA CAR-T cell manufacture.

7.
Cir Pediatr ; 34(3): 138-142, 2021 Jul 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34254752

RESUMO

INTRODUCTION: Congenital paraesophageal hernia (CPH) is a rare pathology in pediatric patients. Clinical signs may occur as early as in newborns, which means it requires early surgical repair. CLINICAL CASES: This is a series of three patients under 1 year of age diagnosed with type IV CPH - with symptoms occurring since they were newborns - who underwent laparoscopic surgical repair. One patient had been diagnosed prenatally. Age at surgery was 6 days, 36 days, and 9 months, respectively. Weight at surgery was 3.60 kg, 3.79 kg, and 8.20 kg, respectively. The patients underwent laparoscopy, with removal of the hernia sac, closure of the diaphragmatic pillars, placement of a reinforcement absorbable mesh, and Nissen fundoplication. Mean operating time was 130 minutes. No intraoperative complications were recorded. One patient developed a sliding hernia, which was subsequently repaired without complications. Mean follow-up time was 24 months.


INTRODUCCION: Las hernias paraesofágicas congénitas (HPC) son una patología poco frecuente en la edad pediátrica. Pueden presentar clínica desde la época neonatal precisando una reparación quirúrgica temprana. CASOS CLINICOS: Presentamos 3 casos diagnosticados de HPC tipo IV en pacientes menores de 1 año, que presentaron síntomas desde la época neonatal, en los que se ha realizado reparación quirúrgica laparoscópica. Un paciente presentaba diagnóstico prenatal. La edad en el momento de la cirugía fue 6 días, 36 días y 9 meses. El peso en el momento de la cirugía fue de 3,60 kg, 3,79 kg y 8,20 kg. Los pacientes fueron intervenidos por laparoscopia realizando excisión del saco herniario, cierre de pilares diafragmáticos, colocación de malla reabsorbible de refuerzo y una funduplicatura Nissen. El tiempo medio de cirugía fue de 130 minutos. No hubo complicaciones intraoperatorias. Un paciente presentó una hernia de deslizamiento que se reparó posteriormente sin complicaciones. El tiempo medio de seguimiento es de 24 meses.


Assuntos
Hérnia Hiatal , Laparoscopia , Criança , Diafragma , Fundoplicatura , Hérnia Hiatal/cirurgia , Humanos , Lactente , Recém-Nascido , Complicações Intraoperatórias
8.
Cir Pediatr ; 34(1): 28-33, 2021 Jan 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33507641

RESUMO

OBJECTIVES: The primary objective was to describe the characteristics and demographics of the surgical procedures carried out at a tertiary hospital during the SARS-CoV-2 pandemic. The secondary objective was to study the impact of the pandemic on the acute appendicitis cases treated at our healthcare facility and to compare them with a pre- SARS-CoV-2 period. MATERIAL AND METHODS: A retrospective study of all patients undergoing surgery at the pediatric surgery department in the pandemic period, from the beginning of the state of emergency in Spain until the first restrictions were removed, was conducted. RESULTS: A total of 61 patients underwent surgery in 58 days vs. 406 patients in the same 2019 period (p < 0.00001). 59.01% of surgeries were urgent. 5.1% of patients had a positive SARS-CoV-2 diagnostic test. 30 different procedures were carried out, with appendectomy being the most frequent one (n = 13, 19.6% of patients). 61.5% of appendicitis cases were complicated vs. 42.4% in the non-COVID period (p = 0.17). Surgical approach was open in 46.1% of patients vs. 6.1% in the non-COVID period (p = 0.004). No statistically significant differences were found in terms of complication rate or hospital stay. CONCLUSIONS: During the SARS-CoV-2 pandemic, a significant decrease in the number of daily procedures was noted, with more than half being urgent. Appendicular pathologies were in a more advanced stage than usual, with a clear trend towards open surgery vs. laparoscopy.


OBJETIVOS: Describir las características y demografía de los procedimientos quirúrgicos realizados en un hospital de tercer nivel durante la pandemia del SARS-CoV-2. Como objetivo secundario se estudia el impacto de la pandemia en las apendicitis agudas tratadas en nuestro centro y su comparación con un periodo previo al SARS-CoV-2. MATERIAL Y METODOS: Estudio retrospectivo incluyendo a todos los pacientes intervenidos por parte del Servicio de Cirugía Pediátrica durante el periodo de pandemia. Abarca desde el primer día del estado de alarma hasta la desescalada de las restricciones. RESULTADOS: Se intervinieron un total de 61 pacientes en 58 días frente a 406 pacientes durante el mismo periodo de 2019 (p < 0,00001). El 59,01% de las intervenciones eran de carácter urgente. Un 5,1% de los pacientes tuvieron un test diagnóstico de SARS-CoV-2 positivo. Se realizaron 30 procedimientos distintos, siendo el más frecuente la apendicectomía (n = 13, 19,6% de los pacientes). El 61,5% de las apendicitis fueron complicadas frente a un 42,4% en periodo no COVID (p = 0,17). El abordaje quirúrgico fue abierto en un 46,1% de los pacientes frente al 6,1% no COVID (p = 0,004). No hubo diferencias estadísticamente significativas en la tasa de complicaciones o la estancia hospitalaria. CONCLUSIONES: Durante la pandemia por SARS-CoV-2 se ha producido una importante disminución del número de procedimientos diarios, pasando a ser más de la mitad de carácter urgente. La patología apendicular se ha presentado más evolucionada de lo habitual, habiendo una clara tendencia a la cirugía abierta frente a la laparoscopia.


Assuntos
Apendicectomia/métodos , Apendicite/cirurgia , COVID-19 , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Laparoscopia/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Pediatria , Estudos Retrospectivos , Espanha , Centros de Atenção Terciária
9.
Front Pediatr ; 8: 600962, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33634051

RESUMO

Introduction: Congenital hypopituitarism (CH) is characterized by a deficiency of one or more pituitary hormones. The pituitary gland is a central regulator of growth, metabolism, and reproduction. The anterior pituitary produces and secretes growth hormone (GH), adrenocorticotropic hormone, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, and prolactin. The posterior pituitary hormone secretes antidiuretic hormone and oxytocin. Epidemiology: The incidence is 1 in 4,000-1 in 10,000. The majority of CH cases are sporadic; however, a small number of familial cases have been identified. In the latter, a molecular basis has frequently been identified. Between 80-90% of CH cases remain unsolved in terms of molecular genetics. Pathogenesis: Several transcription factors and signaling molecules are involved in the development of the pituitary gland. Mutations in any of these genes may result in CH including HESX1, PROP1, POU1F1, LHX3, LHX4, SOX2, SOX3, OTX2, PAX6, FGFR1, GLI2, and FGF8. Over the last 5 years, several novel genes have been identified in association with CH, but it is likely that many genes remain to be identified, as the majority of patients with CH do not have an identified mutation. Clinical manifestations: Genotype-phenotype correlations are difficult to establish. There is a high phenotypic variability associated with different genetic mutations. The clinical spectrum includes severe midline developmental disorders, hypopituitarism (in isolation or combined with other congenital abnormalities), and isolated hormone deficiencies. Diagnosis and treatment: Key investigations include MRI and baseline and dynamic pituitary function tests. However, dynamic tests of GH secretion cannot be performed in the neonatal period, and a diagnosis of GH deficiency may be based on auxology, MRI findings, and low growth factor concentrations. Once a hormone deficit is confirmed, hormone replacement should be started. If onset is acute with hypoglycaemia, cortisol deficiency should be excluded, and if identified this should be rapidly treated, as should TSH deficiency. This review aims to give an overview of CH including management of this complex condition.

10.
Cir Pediatr ; 33(4): 160-165, 2020 Oct 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33016654

RESUMO

OBJECTIVE: To analyze bronchoalveolar lavage diagnostic effectiveness and impact on therapeutic management in pediatric patients. MATERIAL AND METHODS: Retrospective study of patients undergoing bronchoalveolar lavage at the pediatric surgery department from 2009 to 2019. The sample was divided into two groups: hemato-oncological patients and non-hemato-oncological patients. Demographic variables, bronchoalveolar lavage result, and subsequent therapeutic attitude were collected. RESULTS: 45 bronchoalveolar lavages were carried out in 38 patients. The hemato-oncological group consisted of 25 bronchoalveolar lavages. Patient mean age was 9.99 ± 2.34 years. 80% of patients had received anti-infective treatment prior to bronchoalveolar lavage. Bronchoalveolar lavage culture was positive in 52% of cases. Bronchoalveolar lavage results translated into therapeutic management change in 24% of cases (6/25). 3 postoperative complications were recorded, all mild. In the non-hemato-oncological group (n = 20), mean age was 6.70 ± 5.17 years. Bronchoalveolar lavage was positive in 25% of cases, and translated into management change in 5% of patients. Complication rate in this group was 30%. 2 patients required mechanical ventilation. CONCLUSIONS: According to our results, bronchoalveolar lavage in hemato-oncological patients helps achieve microbiological diagnosis in infectious respiratory conditions and is relatively well-tolerated. In non-hemato-oncological patients, diagnostic and therapeutic usefulness is low, and complication rate is not negligible. The risk-benefit balance should be individually considered in each patient.


OBJETIVO: Analizar la eficacia diagnóstica del lavado broncoalveolar y su impacto en el manejo terapéutico en pacientes pediátricos. MATERIAL Y METODOS: Estudio retrospectivo incluyendo a los pacientes a los que se les realizó un lavado broncoalveolar por parte del Servicio de Cirugía Pediátrica entre 2009 y 2019. Se ha dividido la muestra en dos grupos: pacientes hemato-oncológicos y no hemato-oncológicos. Se han recogido variables demográficas, el resultado del lavado broncoalveolar y la actitud terapéutica posterior. RESULTADOS: Se realizaron 45 lavados broncoalveolares en 38 pacientes. El grupo hemato-oncológico constaba de 25 lavados broncoalveolares. Los pacientes tenían una edad media de 9,99 ± 2,34 años. El 80% de los pacientes tenían tratamiento antiinfeccioso previo al lavado broncoalveolar. El cultivo del lavado broncoalveolar fue positivo en el 52% de los casos. El resultado del lavado broncoalveolar influyó en un cambio de manejo terapéutico en un 24% (6/25). Se produjeron 3 complicaciones postoperatorias, todas leves. En el grupo no hemato-oncológico (n = 20) la edad media era de 6,70 ± 5,17 años. El lavado broncoalveolar fue positivo en el 25% y supuso un cambio de manejo en un 5% de los pacientes. Este grupo tuvo una tasa de complicación del 30%, 2 pacientes requirieron ventilación mecánica. CONCLUSIONES: Según nuestros resultados, el lavado broncoalveolar en los pacientes hemato-oncológicos ayuda al diagnóstico microbiológico en procesos respiratorios infecciosos y es relativamente bien tolerado. En los no hemato-oncológicos, tiene una baja rentabilidad diagnóstico-terapéutica con una tasa de complicaciones no desdeñable. Sería necesario individualizar el balance beneficio-riesgo en cada paciente.


Assuntos
Lavagem Broncoalveolar/métodos , Neoplasias Hematológicas/diagnóstico , Infecções Respiratórias/diagnóstico , Adolescente , Lavagem Broncoalveolar/efeitos adversos , Broncoscopia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
11.
Science ; 233(4770): 1311-4, 1986 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-17843359

RESUMO

Planktotrophic larvae that occur beneath the annual sea ice in the Antarctic assimilate organic solutes and preferentially ingest bacteria, whereas they actively exclude phytoplankton. In regions where phytoplankton biomass is temporally limited by light or nutrient concentrations, the growth and development of planktotrophic larvae may not be directly coupled to phytoplankton production.

12.
Ultrasonics ; 88: 148-156, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29654961

RESUMO

In this paper, the study of frequency-dependent ultrasonic attenuation in strongly heterogeneous cementitious materials is addressed. To accurately determine the attenuation over a wide frequency range, it is necessary to have suitable excitation techniques. We have analysed two kinds of ultrasound techniques: contact ultrasound and airborne non-contact ultrasound. The mathematical formulation for frequency-dependent attenuation has been established and it has been revealed that each technique may achieve similar results but requires specific different calibration processes. In particular, the airborne non-contact technique suffers high attenuation due to energy losses at the air-material interfaces. Thus, its bandwidth is limited to low frequencies but it does not require physical contact between transducer and specimen. In contrast, the classical contact technique can manage higher frequencies but the measurement depends on the pressure between the transducer and the specimen. Cement specimens have been tested with both techniques and frequency attenuation dependence has been estimated. Similar results were achieved at overlapping bandwidth and it has been demonstrated that the airborne non-contact ultrasound technique could be a viable alternative to the classical contact technique.

14.
Nucleic Acids Res ; 28(7): E27, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10710444

RESUMO

The identification of cellular RNA expression profiles by differential display (DD) involves the visualization of RT-PCR products from the RNA. Traditionally, DD protocols require 200-500 ng RNA for each RT reaction. Thus, the limiting factor in DD is the amount of RNA available and the sensitivity of the RT reaction. By replacing the type of reverse transcriptase in our method, the sensitivity of DD increased up to 100-fold. Very significantly, the cDNA species obtained are higher in molecular weight, increasing the chances of detection of differential display genes with less background bands. The false positives and background in general also decreased due to the utilization of Taq polymerase antibody to facilitated DNA synthesis in the PCR reaction step. The reverse transcriptases described here may have a greater priming capacity as well as strong processivity which would explain the higher sensitivity accomplished in comparison to more standard reverse transcriptases. Additionally, the application of a more sensitive DD to samples when the amount of RNA is limited would be highly recommended.


Assuntos
Perfilação da Expressão Gênica , DNA Polimerase Dirigida por RNA/metabolismo , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Linhagem Celular , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida
15.
Transplant Proc ; 38(8): 2419-23, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17097955

RESUMO

BACKGROUND: The prevalence of posttransplant hypertension is high, and it appears to be a major risk factor for graft and patient survival. The aim of this study was to assess the efficacy and safety of valsartan, an angiotensin-receptor blocker (ARB), in the treatment of posttransplant hypertension. METHODS: A multinational, multicenter, prospective, randomized, double-blind, placebo-controlled study was performed on the treatment of hypertension (systolic blood pressure [BP] >/= 140 and/or diastolic BP >/= 90 mm Hg) in adult cyclosporin-treated renal transplant recipients randomized to receive either valsartan (80 mg once daily) or a matching placebo for 8 weeks. After the first 4 weeks, furosemide 20 mg twice daily was added on a open basis if systolic BP remained >/= 130 mm Hg and/or diastolic BP remained >/= 85 mm Hg. RESULTS: One hundred fifteen (valsartan = 57, placebo = 58) uncontrolled hypertensive patients despite monotherapy for hypertension, other than angiotensin-converting enzyme inhibitor or ARB, were randomized. In the valsartan group, significant decreases were seen in systolic BP (from 153 +/- 11 to 140.9 +/- 18.35 mm Hg at 4 weeks, and 136.5 +/- 15 mm Hg at 8 weeks) and diastolic BP (from 93 +/- 9 to 85.2 +/- 11.28 mm Hg at 4 weeks, and 83.8 +/- 9.2 mm Hg at 8 weeks). There was no significant change in the placebo group. In the valsartan group, a statistically but not clinically significant reduction was observed in the mean hemoglobin concentration (12.9 +/- 1.6 g/dL versus 13.8 +/- 1.6 g/dL at 4 weeks, P < .01; and 12.3 +/- 1.6 versus 13.8 +/- 1.7 at 8 weeks; P < .001) as well as a significant increase in serum potassium (4.4 +/- 0.5 mmol/L versus 4.1 +/- 0.4 mmol/L at 4 weeks, P < .01) vs placebo. CONCLUSIONS: Valsartan is effective in the treatment of posttransplant hypertension and is well tolerated.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Transplante de Rim/efeitos adversos , Tetrazóis/uso terapêutico , Valina/análogos & derivados , Adulto , Diástole/efeitos dos fármacos , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Complicações Pós-Operatórias/tratamento farmacológico , Segurança , Sístole/efeitos dos fármacos , Valina/uso terapêutico , Valsartana
17.
J Am Coll Cardiol ; 21(7): 1667-71, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8496535

RESUMO

OBJECTIVES: This study aimed to compare indium-111 (111In)-monoclonal antimyosin antibody uptake in patients with dilated cardiomyopathy before heart transplantation with the histologic findings in the explanted hearts. BACKGROUND: A high prevalence of 111In-monoclonal antimyosin antibody uptake has been described in patients with dilated cardiomyopathy, suggesting the presence of active, ongoing myocyte damage; however, no correlation between monoclonal antimyosin antibodies and histologic findings is available in these patients. METHODS: A consecutive series of 21 patients with dilated cardiomyopathy awaiting heart transplantation were studied with monoclonal antimyosin antibodies before the operation, and the results were compared with the histologic analysis of the explanted hearts. The interval between monoclonal antimyosin antibody studies and transplantation was 1 to 90 days (mean 58 +/- 31). RESULTS: Using a semiquantitative method (heart/lung ratio), monoclonal antimyosin antibody uptake was present in 15 (71%) of 21 patients, but active myocarditis in the explanted hearts was detected in only 7. In 11 patients, intense monoclonal antimyosin antibody uptake coexisting with absent myocyte damage or cellular infiltration of explanted hearts was noted. One patient who showed preoperative monoclonal antimyosin antibody uptake underwent transplantation 11 h later, and ex vivo diffuse myocardial antimyosin uptake was detected, but active myocarditis was seen only at cardiectomy in only a small area of the heart; the rest of the myocardium showed no signs of myocyte damage. CONCLUSIONS: In dilated cardiomyopathy, monoclonal antimyosin antibody uptake cannot be equated with the presence of an inflammatory response detected in the myocardium of the explanted heart.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Miocardite/diagnóstico por imagem , Adulto , Anticorpos Monoclonais , Cardiomiopatia Dilatada/patologia , Feminino , Transplante de Coração , Humanos , Radioisótopos de Índio , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Miosinas/imunologia , Estudos Prospectivos , Cintilografia
18.
Leukemia ; 11(7): 1131-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9205002

RESUMO

P-glycoprotein-mediated multidrug resistance has emerged as one of the most attractive targets to improve anticancer therapy. The P-glycoprotein functions as an energy-dependent, membrane transport pump capable of decreasing the intracellular concentration of a broad range of chemotherapeutic agents. Pharmaceuticals which inhibit P-glycoprotein transport activity are currently being evaluated in clinical trials. Characterization of P-glycoprotein functional activity is critical in determining if these multidrug resistance reversal agents improve therapeutic responses of tumors expressing P-glycoprotein. In this report, we directly compare and characterize assays using rhodamine 123, dimethyloxadicarbocyanine iodide (DiOC2), [3H]daunorubicin and hexakis(2-methoxyisobutyl isonitrile)technetium(I) ([(99m)Tc]Sestamibi) as P-glycoprotein transport probes to quantitate functional activity. The accumulation of certain substrates is concentration dependent and the parameters which determine probe accumulation are impacted by the level of P-glycoprotein expression. In addition, higher concentrations of reversal agents are required to inhibit multidrug resistance in cell lines expressing higher levels of P-glycoprotein. Furthermore, the concentration of reversal agents required to inhibit completely P-glycoprotein transport activity is higher than generally recognized. Thus, the level of P-glycoprotein expression may confound intersample comparisons unless sensitive probes are used in combination with saturating concentrations of potent reversal agents. These results highlight the importance of carefully characterizing assay systems under uniform conditions to quantitate P-glycoprotein function.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Daunorrubicina/farmacocinética , Resistência a Múltiplos Medicamentos , Humanos , Tecnécio Tc 99m Sestamibi/metabolismo , Células Tumorais Cultivadas
19.
Physiol Behav ; 151: 478-84, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26300468

RESUMO

Evaluative conditioning may be an important mechanism for learning food preferences and aversions; however, in both real life and experimental settings it has not been consistently successful. The current study aimed to gain more insight into which underlying factors may contribute to a successful outcome of olfactory evaluative conditioning. Two groups of 18 participants came in on three consecutive days, and were repeatedly exposed to four novel, neutral odors (CS) coupled to varying disliked, neutral, liked, or no stimuli (taste and/or pictures, US), following a 50% reinforcement schedule, leading to 40 odor presentations per session. Liking ratings, as well as changes in the autonomic nervous system were assessed before, during and after conditioning. We were able to induce negative, but not positive, affective changes by pairing neutral odors with tastes and pictures differing in valence. Negative as well as multimodal stimuli appear to be more potent US, since they may be considered more salient. Lastly, results of the current study imply that heart rate is responsive to changes in valence of olfactory stimuli, and perhaps even more sensitive than explicit ratings of liking.


Assuntos
Condicionamento Psicológico , Preferências Alimentares/psicologia , Percepção Gustatória , Condicionamento Psicológico/fisiologia , Reconhecimento Facial/fisiologia , Feminino , Preferências Alimentares/fisiologia , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Percepção Olfatória/fisiologia , Estimulação Física , Testes Psicológicos , Esquema de Reforço , Percepção Gustatória/fisiologia , Adulto Jovem
20.
An Pediatr (Barc) ; 83(3): 201-8, 2015 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-25468452

RESUMO

INTRODUCTION: Tufted angioma (TA) is a rare benign vascular tumor that mostly appears during infancy or early childhood, although there are cases reported in adults. Clinical presentation and evolution of TA can vary. Histologically, it takes on a classic appearance of vascular tufts ("cannon ball" like appearance). PATIENTS AND METHODS: A retrospective observational study was conducted that included all patients diagnosed with TA at our center in the last 20 years. RESULTS: A series of 9 cases of tufted angioma in childhood are presented, 77.7% of which were congenital. This represents a frequency higher than previously described. Spontaneous regression was observed in 55.5% of the cases, and was more frequent in the congenital TA group. Unlike other TA series reported in the literature, a higher proportion of patients with spontaneous regression was observed in this series, with a higher prevalence in females (6 out of 9 children) and predominantly located in the upper limbs. None of our patients had Kasabach-Merritt phenomenon. CONCLUSIONS: There are many ways of treating TA, but none are uniformly effective. Given the high rate of spontaneous regression in congenital or early TA, we suggest that, in the absence of other complications, monitoring would be a good option for management.


Assuntos
Hemangioma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Criança , Feminino , Hemangioma/terapia , Humanos , Lactente , Recém-Nascido , Masculino , Regressão Neoplásica Espontânea , Estudos Retrospectivos , Neoplasias Cutâneas/terapia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA