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1.
Pediatr Surg Int ; 39(1): 191, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140693

RESUMO

PURPOSE: Preoperative evaluation of Image Defined Risk Factors (IDRFs) in neuroblastoma (NB) is crucial for determining suitability for upfront resection or tumor biopsy. IDRFs do not all carry the same weighting in predicting tumor complexity and surgical risk. In this study we aimed to assess and categorize a surgical complexity (Surgical Complexity Index, SCI) in NB resection. METHODS: A panel of 15 surgeons was involved in an electronic Delphi consensus survey to identify and score a set of shared items predictive and/or indicative of surgical complexity, including the number of preoperative IDRFs. A shared agreement included the achievement of at least 75% consensus focused on a single or two close risk categories. RESULTS: After 3 Delphi rounds, agreement was established on 25/27 items (92.6%). A severity score was established for each item ranging from 0 to 3 with an overall SCI range varying from a minimum score of zero to a maximum score of 29 points for any given patient. CONCLUSIONS: A consensus on a SCI to stratify the risks related to neuroblastoma tumor resection was established by the panel experts. This index will now be deployed to critically assign a better severity score to IDRFs involved in NB surgery.


Assuntos
Neuroblastoma , Humanos , Neuroblastoma/cirurgia , Neuroblastoma/patologia , Fatores de Risco , Cuidados Pré-Operatórios , Biópsia
2.
Br J Surg ; 108(6): 632-637, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33720314

RESUMO

Fetal medicine is a super-specialty enterprise and a technology-driven field. The growth and interest in fetal surgery can be largely attributed to advances in fetal imaging and bespoke instruments for in utero intervention. Previously fatal fetal conditions are now being treated using open surgery, minimally invasive procedures, and percutaneous fetal technologies. Several fetal conditions, including myelomeningocele and twin-to-twin transfusion syndrome, have been tested rigorously in RCTs. However, as the specialty of fetal surgery grows, a robust evidence base with long-term follow-up is obligatory for every procedure. This article offers an overview of fetal surgery and antenatal intervention. As more cutting edge therapies come into clinical practice, growing public opinion and medical ethics will play a significant role in the future of this multidisciplinary specialty.


Assuntos
Doenças Fetais/cirurgia , Feto/cirurgia , Feminino , Humanos , Gravidez
3.
Br J Surg ; 107(6): 636-646, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32083325

RESUMO

BACKGROUND: Antireflux surgery is commonly performed in children, yet evidence for its efficacy is limited. The aim of this review was to determine the effect of antireflux surgery with regard to objective measures of quality of life (QoL) and value of upper gastrointestinal investigations in neurologically normal (NN) and neurologically impaired (NI) children. METHODS: A systematic review was conducted of articles reporting children undergoing antireflux surgery in whom preoperative and postoperative objective testing was performed. Primarily, Embase, CINAHL, MEDLINE and PubMed were searched from inception to April 2019. Methodological Index for Non-randomized Studies (MINORS) criteria were used to assess article quality. RESULTS: Of 789 articles, 14 met the eligibility criteria, 12 prospective observational and 2 retrospective studies. The median MINORS score was 59·4 (i.q.r. 39 to 62·5) per cent. Seven studies reported assessment of validated QoL measures before and after antireflux surgery in 148 children. Follow-up ranged from 1 to 180 months. All studies confirmed significant improvements in QoL measures among NN and NI children at all follow-up points. Eleven studies reported on preoperative and postoperative investigations in between 416 and 440 children children. Follow-up ranged from 0·5 to 180 months. Nine studies confirmed improvements in gastro-oesophageal reflux using 24-h oesophageal pH monitoring with or without manometry, but conflicting results were identified for four studies reporting gastric emptying. No studies reported fluoroscopy or endoscopy adequately. CONCLUSION: Based on the results of studies of low-to-moderate quality, antireflux surgery improved QoL and reduced oesophageal acid exposure in NN and NI children in the short and medium term. Although antireflux surgery is a common elective operation, the lack of rigorous preoperative and postoperative evaluation(s) in the majority of patient-reported studies is striking.


ANTECEDENTES: La cirugía antirreflujo (antireflux surgery, ARS) se realiza con frecuencia en niños, aunque la evidencia sobre su eficacia es limitada. Nos propusimos determinar la eficacia de la ARS con respecto a medidas objetivas de calidad de vida (quality of life, QoL) y la utilidad de las exploraciones del tracto gastrointestinal superior en niños con funciones neurológicas normales (neurologically normal, NN) y con discapacidad neurológica (neurologically impaired, NI). MÉTODOS: Se llevó a cabo una revisión sistemática (de acuerdo con la normativa PRISMA) de artículos que describiesen series de niños sometidos a ARS en los que se realizaron pruebas objetivas preoperatorias y postoperatorias. Principalmente, se efectuó una búsqueda en EMBASE, CINAHL, Medline y Pubmed desde un comienzo hasta 04/19. La calidad de los artículos se evaluó siguiendo los criterios MINORS. RESULTADOS: De 789 artículos, 14 reunían los criterios de elegibilidad - 12 estudios observacionales prospectivos y 2 estudios retrospectivos. La mediana de la puntuación MINORS fue de 59,4 % (rango intercuartílico 23,4%). Siete estudios describieron la evaluación de medidas de QoL validadas antes y después de ARS en 148 niños. El seguimiento varió de 1 a 180 meses. Todos los estudios confirmaron mejorías significativas en medidas de QoL en los niños NN y NI en todos los puntos del seguimiento. Once estudios describieron sobre las investigaciones preoperatorias y postoperatorias en 507 niños. El seguimiento oscilaba de 0,5 a 180 meses. Nueve estudios confirmaron mejorías en el reflujo gastroesofágico utilizando la monitorización del pH esofágico de 24 horas +/- manometría, pero los resultados eran contradictorios en 3 estudios que evaluaron el vaciamiento gástrico. Ningún estudio describió de forma adecuada los datos de la fluoroscopia o endoscopia. CONCLUSIÓN: De los estudios identificados de baja o moderada calidad, en un seguimiento a corto y medio plazo, la ARS mejora la QoL y reduce la exposición del esófago al ácido en niños NN y niños NI. A pesar de que la ARS es una cirugía electiva habitual, es llamativa la falta de evaluaciones preoperatorias y postoperatorias rigurosas en la mayoría de los estudios de pacientes.


Assuntos
Fundoplicatura , Refluxo Gastroesofágico/cirurgia , Doenças do Sistema Nervoso/complicações , Estudos de Casos e Controles , Criança , Refluxo Gastroesofágico/complicações , Humanos , Qualidade de Vida , Resultado do Tratamento
5.
Br J Surg ; 100(13): 1833-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24227372

RESUMO

BACKGROUND: The anatomical defect in congenital diaphragmatic hernia (CDH) can usually be closed primarily but prosthetic patch repair may be required in newborns with a deficient diaphragm. High rates of patch failure and hernia recurrence (up to 50 per cent) have been reported. This study evaluated contemporary outcomes following patch repair of CDH at a UK paediatric surgical centre. METHODS: Medical records of newborns undergoing surgery for CDH between 1 February 1990 and 1 November 2010, and attending a multidisciplinary follow-up clinic, were examined. Operative details and patch utilization are reported. RESULTS: Of 118 newborns with CDH, 37 required a patch to the diaphragmatic defect. Gore-Tex® patches were used in 35 and biological Surgisis® patches in two. Eight babies additionally required an abdominal wall patch. Seven infants had an abdominal patch alone with primary diaphragm repair. A total of 102 infants (86·4 per cent) survived after surgery. Two early recurrences were both related to the use of biological patches, leading to revisional surgery with Gore-Tex® patch reconstruction. Diaphragmatic patch use was associated with a greater requirement for intensive cardiovascular and respiratory support, although there was no significant difference in mortality between patch versus primary diaphragm repair. The mortality rate was significantly higher among infants requiring abdominal wall patching (with or without a diaphragmatic patch): 40 per cent (6 of 15) versus 9·7 per cent (10 of 103) (P = 0·006). Postoperative survival rates for infants with a diaphragmatic patch alone, abdominal wall patch alone, and both abdominal and diaphragmatic patches were 86 per cent (25 of 29), 57 per cent (4 of 7) and 63 per cent (5 of 8) respectively. CONCLUSION: Prosthetic diaphragmatic hernia repair at this centre has a good outcome and low rate of recurrence (5 per cent). The recognition of an inadequate abdominal domain prenatally may additionally prove to be a useful marker for predicting increased mortality in newborns with CDH.


Assuntos
Hérnias Diafragmáticas Congênitas , Politetrafluoretileno/uso terapêutico , Próteses e Implantes , Telas Cirúrgicas , Seguimentos , Hérnia Diafragmática/cirurgia , Humanos , Recém-Nascido , Recidiva , Resultado do Tratamento
6.
Br J Surg ; 104(12): 1589-1590, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29044487
7.
Br J Surg ; 99(7): 929-38, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22513659

RESUMO

BACKGROUND: Addition of glutamine to parenteral nutrition in surgical infants remains controversial. The aim of this trial was to determine whether glutamine supplementation of parenteral nutrition in infants requiring surgery would reduce the time to full enteral feeding and/or decrease the incidence of sepsis and septicaemia. METHODS: A prospective double-blind multicentre randomized clinical trial was performed in surgical infants less than 3 months old who required parenteral nutrition. Patients were allocated to treatment or control groups by means of minimization. Infants received either 0·6 g per kg per day alanyl-glutamine (treatment group) or isonitrogenous isocaloric parenteral nutrition (control group) until full enteral feeding was achieved. Primary outcomes were time to full enteral feeding and incidence of sepsis. Cox regression analysis was used to compare time to full enteral feeding, and to calculate risk of sepsis/septicaemia. RESULTS: A total of 174 patients were randomized, of whom 164 completed the trial and were analysed (82 in each group). There was no difference in time to full enteral feeding or time to first enteral feeding between groups, and supplementation with glutamine had no effect on the overall incidence of sepsis or septicaemia. However, during total parenteral nutrition (before the first enteral feed), glutamine administration was associated with a significantly decreased risk of developing sepsis (hazard ratio 0·33, 95 per cent confidence interval 0·15 to 0·72; P = 0·005). CONCLUSION: Glutamine supplementation during parenteral nutrition did not reduce the incidence of sepsis in surgical infants with gastrointestinal disease. REGISTRATION NUMBER: ISRCTN83168963 (http://www.controlled-trials.com).


Assuntos
Suplementos Nutricionais , Gastroenteropatias/cirurgia , Glutamina/administração & dosagem , Nutrição Parenteral/métodos , Peso Corporal , Método Duplo-Cego , Ingestão de Energia , Feminino , Gastroenteropatias/dietoterapia , Humanos , Lactente , Recém-Nascido , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sepse/prevenção & controle
8.
Eur J Surg Oncol ; 48(1): 283-291, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34489122

RESUMO

INTRODUCTION: Surgery plays a key role in the management of Neuroblastic tumours (NB), where the standard approach is open surgery, while minimally invasive surgery (MIS) may be considered an option in selected cases. The indication(s) and morbidity of MIS remain undetermined due to small number of reported studies. The aim of this study was to critically address the contemporary indications, morbidity and overall survival (OS) and propose guidelines exploring the utility of MIS for NB. MATERIALS & METHODS: A SIOPEN study where data of patients with NB who underwent MIS between 2005 and 2018, including demographics, tumour features, imaging, complications, follow up and survival, were extracted and then analysed. RESULTS: A total of 222 patients from 16 centres were identified. The majority were adrenal gland origin (54%) compared to abdominal non-adrenal and pelvic (16%) and thoracic (30%). Complete and near complete macroscopic resection (>95%) was achieved in 95%, with 10% of cases having conversion to open surgery. Complications were reported in 10% within 30 days of surgery. The presence of IDRF (30%) and/or tumour volume >75 ml were risk factors for conversion and complications in multivariate analysis. Overall mortality was 8.5%. CONCLUSIONS: MIS for NB showed that it is a secure approach allowing more than 95% resection. The presence of IDRFs was not an absolute contraindication for MIS. Conversion to open surgery and overall complication rates were low, however they become significant if tumour volume >75 mL. Based on these data, we propose new MIS guidelines for neuroblastic tumours.


Assuntos
Neoplasias Abdominais/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Ganglioneuroblastoma/cirurgia , Ganglioneuroma/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neuroblastoma/cirurgia , Neoplasias Pélvicas/cirurgia , Neoplasias Torácicas/cirurgia , Neoplasias Abdominais/patologia , Neoplasias das Glândulas Suprarrenais/patologia , Criança , Pré-Escolar , Conversão para Cirurgia Aberta , Feminino , Ganglioneuroblastoma/patologia , Ganglioneuroma/patologia , Humanos , Lactente , Masculino , Neuroblastoma/patologia , Neoplasias Pélvicas/patologia , Guias de Prática Clínica como Assunto , Neoplasias Torácicas/patologia , Carga Tumoral
10.
Ann R Coll Surg Engl ; 103(4): e114-e115, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33661045

RESUMO

Neuropathic bladder may be a co-associated morbidity in newborn babies following resection of a sacrococcygeal teratoma. We report a case of a male newborn showing features of incomplete urinary voiding requiring intermittent catheterisation after operation for bladder emptying. Videourodynamic assessment excluded neuropathic bladder and posterior urethral valves were demonstrated on micturating cystography. Urology outcomes have been excellent following curative valve ablation. This report highlights the crucial importance of being aware of the rare coexistence of lower urinary tract pathology in male babies with sacrococcygeal teratoma. Routine urodynamic assessment should be considered in all children following sacrococcygeal teratoma resection.


Assuntos
Complicações Pós-Operatórias/diagnóstico , Teratoma/cirurgia , Uretra/anormalidades , Bexiga Urinaria Neurogênica/diagnóstico , Anormalidades Urogenitais/diagnóstico , Cistografia , Diagnóstico Diferencial , Humanos , Recém-Nascido , Masculino , Região Sacrococcígea , Teratoma/complicações , Teratoma/diagnóstico , Uretra/diagnóstico por imagem , Anormalidades Urogenitais/etiologia
11.
BJS Open ; 5(3)2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-34052849

RESUMO

BACKGROUND: Inferior vena cava (IVC) tumour thrombus in children with Wilms tumour is typically managed with neoadjuvant chemotherapy with the intention of achieving thrombus regression in order to minimize the risks associated with complex vascular surgery. METHODS: A systematic review of Medline and Embase databases was undertaken to identify all eligible studies with reference to thrombus viability in Wilms tumour index cases with caval/cardiac extension. A meta-analysis of proportions was utilized for pooled thrombus viability data across studies. Logistic regression was used to analyse the relationship between thrombus viability and duration of chemotherapy. RESULTS: Thirty-five eligible observational studies and case reports met inclusion criteria describing a total of 236 patients with thrombus viability data. The pooled proportion of patients with viable tumour thrombus after neoadjuvant chemotherapy was 0.53 (0.43-0.63). Logistic regression analysis of 54 patients receiving either a standard (4-6 weeks) or extended (more than 6 weeks) course of neoadjuvant chemotherapy resulted in an odds ratio of 3.14 (95 per cent c.i. 0.97 to 10.16), P = 0.056, with extended course therapy trending towards viable tumour thrombus. CONCLUSION: Preoperative chemotherapy is successful in achieving non-viability of caval and cardiac thrombi in around 50 per cent of children, without added benefit from extended cycles of neoadjuvant chemotherapy. Risks versus benefits of extirpative vascular surgery must be considered, therefore, for these high-risk patients.


Assuntos
Neoplasias Renais , Trombose , Tumor de Wilms , Criança , Humanos , Neoplasias Renais/tratamento farmacológico , Terapia Neoadjuvante , Estudos Retrospectivos , Trombose/tratamento farmacológico , Veia Cava Inferior/cirurgia , Tumor de Wilms/tratamento farmacológico , Tumor de Wilms/cirurgia
12.
Ultrasound Obstet Gynecol ; 35(5): 609-14, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20178116

RESUMO

OBJECTIVES: Intrathoracic liver herniation (ILH) is being used to estimate prognosis and hence guide antenatal interventions in fetal congenital diaphragmatic hernia (CDH). However, the literature regarding its utility in this role is conflicting. This review systematically examines the currently available evidence of ILH use in fetal CDH. METHODS: MEDLINE and EMBASE databases were searched for the terms ((congenital diaphragmatic hernia) OR CDH) AND liver. Inclusion criteria were human case series of fetuses diagnosed with CDH using either ultrasound or magnetic resonance imaging. Included studies were required to have reported the antenatal liver position and the outcome (survival or not). Case reports, reviews and eventration series were excluded. Studies reporting similar cases from the same center over an overlapping time period were considered duplicates; only the larger of the studies were therefore included. Absolute totals were extracted and sums calculated. Fisher's exact test (FET) was used to compare survival rates in different groups. RESULTS: The original search retrieved 338 studies. Applying inclusion/exclusion criteria and removing duplicates left 21 case series in 20 studies. Retrieved studies differed in the definitions of liver herniation, survival and treatment modality. In total, there were 407 fetuses in the liver-up (herniated) and 303 in the liver-down (not herniated) groups. Survival rates were 45.4% and 73.9%, respectively. The difference was statistically significant (FET = 56.4, P < 0.005). Sensitivity analysis for cases that had only conventional postnatal treatment was still significant (FET = 52.8, P < 0.005). CONCLUSIONS: Liver herniation is associated with poorer prognosis in fetal CDH. Grading liver herniation or using it as part of a panel of markers may enhance the value of liver herniation as a prognostic test in fetal CDH.


Assuntos
Hérnia Diafragmática/diagnóstico , Hepatopatias/diagnóstico , Feminino , Idade Gestacional , Hérnia Diafragmática/mortalidade , Hérnias Diafragmáticas Congênitas , Humanos , Hepatopatias/congênito , Hepatopatias/mortalidade , Gravidez , Diagnóstico Pré-Natal/métodos , Prognóstico
13.
J Pediatr Surg ; 55(10): 2026-2029, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31837839

RESUMO

BACKGROUND: Ovarian tumors in children are rare, mature teratoma being the most common histological entity. Robust guidelines to aid patient follow-up after resection are distinctly lacking. Although mature teratoma has a very good prognosis following complete resection, small studies have reported the occurrence of metachronous disease and recurrence to a variable degree (2.5-23% of patients). Nevertheless, there are surgeons who recommend no follow-up is required for these children after primary tumor resection. We investigated the incidence of (i) recurrence and (ii) metachronous disease in pediatric patients following ovarian tumor resection. METHODS: Retrospective multicenter study amongst UK pediatric surgical oncology centers. Females <16 years with diagnosis of ovarian tumor from 2006 to 2016 were included. Functional/neonatal ovarian cysts were excluded. RESULTS: Three hundred ten patients with ovarian tumors treated at 12 surgical oncology centers were identified. Mean age at surgery was 11 years [IQR 8-14]. Most common diagnosis were mature teratoma (57%, 177 cases), immature teratoma (10.9%, 34 cases) and serous cystadenoma (7.7%, 24 cases). 8.1% (25 cases) of all females were identified with tumor recurrence/ metachronous disease. 5.1% (9 cases) of patients with mature teratoma had recurrent/ metachronous disease. Most of these patients were diagnosed at routine clinic follow-up. CONCLUSION: Our study clearly shows that ovarian tumor recurrence(s) and metachronous disease occur, even in "benign" ovarian tumors. We recommend female pediatric patients should have robust follow-up care plans after primary diagnosis and resection of ovarian tumor(s). LEVEL OF EVIDENCE STATEMENT: This is a level II evidence study. It is a retrospective multicentre collaborative study which summarizes data from a national cohort of children.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Ovarianas , Teratoma , Adolescente , Criança , Feminino , Humanos , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Teratoma/epidemiologia , Teratoma/patologia , Reino Unido
14.
J Laryngol Otol ; : 1-4, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31971119

RESUMO

BACKGROUND: Whilst aortopexy is an accepted and established procedure, there remains considerable heterogeneity within the literature, with inconsistencies in both the approach taken and the technique employed. Furthermore, limited data exist on both patient selection and long-term outcomes. This study aimed to report the experience of managing severe tracheomalacia by way of aortopexy in a large UK paediatric centre. METHOD: A retrospective case note review was conducted. Mean follow up was five years. RESULTS: Twenty-five patients underwent aortopexy for severe tracheomalacia caused by external vascular compression. Acute life-threatening events precipitated investigation in 72 per cent of cases. Twenty-one patients initially presented to ENT services for investigation, which comprised upper airway endoscopy and imaging with computed tomography angiography. Post-operatively, the majority of patients demonstrated complete resolution of symptoms and were discharged from all associated services. Only four patients required a tracheostomy. CONCLUSION: Aortopexy offers an effective method of treating severe tracheomalacia due to vascular compression.

15.
Br J Neurosurg ; 22(4): 575-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18661320

RESUMO

Infantile myofibromatosis (IM) is a rare pathological entity characterized by solitary or multiple nodular skin, soft tissues or bony lesions. Craniovertebral (CV) junction lesions are rare. We report the successful management of a solitary IM involving the posterior elements of the CV junction in a 6-month-old child.


Assuntos
Vértebras Cervicais , Miofibromatose/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Doenças do Nervo Acessório/etiologia , Diatermia/métodos , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Miofibromatose/cirurgia , Paralisia/etiologia , Complicações Pós-Operatórias/etiologia , Neoplasias de Tecidos Moles/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico
16.
Arch Dis Child Fetal Neonatal Ed ; 91(5): F381-4, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16923940

RESUMO

Oesophageal atresia-tracheo-oesophageal fistula has featured in paediatric surgery since its beginnings. The first successful primary repair was in 1941. With overall survival now exceeding 90% in dedicated centres, the emphasis has changed to reducing morbidity and achieving improvements in the quality of life. An overview of current and emerging strategies in managing patients with this condition is presented. Advances in developmental biology and molecular genetics reflecting improved understanding of the pathogenesis are highlighted.


Assuntos
Atresia Esofágica/cirurgia , Fístula Traqueoesofágica/cirurgia , Atresia Esofágica/complicações , Atresia Esofágica/reabilitação , Humanos , Recém-Nascido , Prognóstico , Qualidade de Vida , Fístula Traqueoesofágica/complicações , Fístula Traqueoesofágica/reabilitação
18.
Oncogenesis ; 4: e138, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25664931

RESUMO

Therapies targeting cancer metastasis are challenging owing to the complexity of the metastatic process and the high number of effectors involved. Although tumour hypoxia has previously been associated with increased aggressiveness as well as resistance to radio- and chemotherapy, the understanding of a direct link between the level and duration of hypoxia and the individual steps involved in metastasis is still missing. Using live imaging in a chick embryo model, we have demonstrated that the exposure of neuroblastoma cells to 1% oxygen for 3 days was capable of (1) enabling cell migration towards blood vessels, (2) slowing down their velocity within blood vessels to facilitate extravasation and (3) promoting cell proliferation in primary and secondary sites. We have shown that cells do not have to be hypoxic anymore to exhibit these acquired capabilities as a long-term memory of prior hypoxic exposure is kept. Furthermore, non-hypoxic cells can be influenced by neighbouring hypoxic preconditioned cells and be entrained in the metastatic progression. The acquired aggressive phenotype relies on hypoxia-inducible factor (HIF)-dependent transcription of a number of genes involved in metastasis and can be impaired by HIF inhibition. Altogether, our results demonstrate the need to consider both temporal and spatial tumour heterogeneity because cells can 'remember' an earlier environment and share their acquired phenotype with their close neighbours. As a consequence, it is necessary to monitor the correct hypoxic markers to be able to predict the consequences of the cells' history on their behaviour and their potential response to therapies.

19.
J Appl Physiol (1985) ; 77(2): 1036-43, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8002489

RESUMO

We designed an accurate method to study respiratory static volume-pressure relationships in small fetal and neonatal animals on the basis of Archimedes' principle. Our method eliminates the error caused by the compressibility of air (Boyle's law) and is sensitive to a volume change of as little as 1 microliters. Fetal and neonatal rats during the period of rapid lung development from day 19.5 of gestation (term = day 22) to day 3.5 postnatum were studied. The absolute lung volume at a transrespiratory pressure of 30-40 cmH2O increased 28-fold from 0.036 +/- 0.006 (SE) to 0.994 +/- 0.042 ml, the volume per gram of lung increased 14-fold from 0.39 +/- 0.07 to 5.59 +/- 0.66 ml/g, compliance increased 12-fold from 2.3 +/- 0.4 to 27.3 +/- 2.7 microliters/cmH2O, and specific compliance increased 6-fold from 24.9 +/- 4.5 to 152.3 +/- 22.8 microliters.cmH2O-1.g lung-1. This technique, which allowed us to compare changes during late gestation and the early neonatal period in small rodents, can be used to monitor and evaluate pulmonary functional changes after in utero pharmacological therapies in experimentally induced abnormalities such as pulmonary hypoplasia, surfactant deficiency, and congenital diaphragmatic hernia.


Assuntos
Animais Recém-Nascidos/fisiologia , Feto/fisiologia , Medidas de Volume Pulmonar/métodos , Pulmão/fisiologia , Mecânica Respiratória/fisiologia , Pressão do Ar , Animais , Animais Recém-Nascidos/anatomia & histologia , Feminino , Feto/anatomia & histologia , Idade Gestacional , Pulmão/anatomia & histologia , Pulmão/crescimento & desenvolvimento , Complacência Pulmonar/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley
20.
Arch Dis Child Fetal Neonatal Ed ; 78(3): F204-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9713033

RESUMO

AIMS: To study the effect of prenatal glucocorticoid treatment on endothelial nitric oxide synthase (eNOS) expression in rats with congenital diaphragmatic hernia (CDH). METHODS: CDH was induced in fetal rats by the maternal administration of nitrofen on day 9.5 of gestation. Dexamethasone was administered on days 18.5 and 19.5 before delivery of the fetuses on days 20.5 and 21.5. Pulmonary eNOS protein expression was studied by western immunoblotting and immunohistochemistry. RESULTS: On day 20.5, eNOS expression was significantly reduced in CDH pups compared with normal control rats. Dexamethasone treated CDH pups had eNOS concentrations equivalent to those of normal animals. By day 21.5, however, there was no detectable difference in eNOS expression between the experimental groups. CONCLUSIONS: eNOS is deficient in near term (day 20.5) CDH rats. Dexamethasone restores eNOS expression in these animals to that seen in normal rat lungs. At term, the precise role of eNOS in the pathophysiology of CDH remains uncertain.


Assuntos
Dexametasona/farmacologia , Endotélio Vascular/enzimologia , Glucocorticoides/farmacologia , Hérnias Diafragmáticas Congênitas , Óxido Nítrico Sintase/efeitos dos fármacos , Animais , Western Blotting , Feminino , Doenças Fetais/enzimologia , Herbicidas , Hérnia Diafragmática/induzido quimicamente , Hérnia Diafragmática/enzimologia , Pulmão/irrigação sanguínea , Óxido Nítrico Sintase/deficiência , Óxido Nítrico Sintase/metabolismo , Éteres Fenílicos , Gravidez , Ratos , Ratos Sprague-Dawley
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