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1.
Lancet Oncol ; 24(9): 978-988, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37433316

RESUMO

BACKGROUND: Paediatric early warning systems (PEWS) aid in the early identification of clinical deterioration events in children admitted to hospital. We aimed to investigate the effect of PEWS implementation on mortality due to clinical deterioration in children with cancer in 32 resource-limited hospitals across Latin America. METHODS: Proyecto Escala de Valoración de Alerta Temprana (Proyecto EVAT) is a quality improvement collaborative to implement PEWS in hospitals providing childhood cancer care. In this prospective, multicentre cohort study, centres joining Proyecto EVAT and completing PEWS implementation between April 1, 2017, and May 31, 2021, prospectively tracked clinical deterioration events and monthly inpatient-days in children admitted to hospital with cancer. De-identified registry data reported between April 17, 2017, and Nov 30, 2021, from all hospitals were included in analyses; children with limitations on escalation of care were excluded. The primary outcome was clinical deterioration event mortality. Incidence rate ratios (IRRs) were used to compare clinical deterioration event mortality before and after PEWS implementation; multivariable analyses assessed the correlation between clinical deterioration event mortality and centre characteristics. FINDINGS: Between April 1, 2017, and May 31, 2021, 32 paediatric oncology centres from 11 countries in Latin America successfully implemented PEWS through Proyecto EVAT; these centres documented 2020 clinical deterioration events in 1651 patients over 556 400 inpatient-days. Overall clinical deterioration event mortality was 32·9% (664 of 2020 events). The median age of patients with clinical deterioration events was 8·5 years (IQR 3·9-13·2), and 1095 (54·2%) of 2020 clinical deterioration events were reported in male patients; data on race or ethnicity were not collected. Data were reported per centre for a median of 12 months (IQR 10-13) before PEWS implementation and 18 months (16-18) after PEWS implementation. The mortality rate due to a clinical deterioration event was 1·33 events per 1000 patient-days before PEWS implementation and 1·09 events per 1000 patient-days after PEWS implementation (IRR 0·82 [95% CI 0·69-0·97]; p=0·021). In the multivariable analysis of centre characteristics, higher clinical deterioration event mortality rates before PEWS implementation (IRR 1·32 [95% CI 1·22-1·43]; p<0·0001), being a teaching hospital (1·18 [1·09-1·27]; p<0·0001), not having a separate paediatric haematology-oncology unit (1·38 [1·21-1·57]; p<0·0001), and having fewer PEWS omissions (0·95 [0·92-0·99]; p=0·0091) were associated with a greater reduction in clinical deterioration event mortality after PEWS implementation; no association was found with country income level (IRR 0·86 [95% CI 0·68-1·09]; p=0·22) or clinical deterioration event rates before PEWS implementation (1·04 [0·97-1·12]; p=0·29). INTERPRETATION: PEWS implementation was associated with reduced clinical deterioration event mortality in paediatric patients with cancer across 32 resource-limited hospitals in Latin America. These data support the use of PEWS as an effective evidence-based intervention to reduce disparities in global survival for children with cancer. FUNDING: American Lebanese Syrian Associated Charities, US National Institutes of Health, and Conquer Cancer Foundation. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.


Assuntos
Deterioração Clínica , Neoplasias , Criança , Humanos , Masculino , Pré-Escolar , Adolescente , Estudos de Coortes , Estudos Prospectivos , América Latina/epidemiologia , Neoplasias/terapia , Hospitais
2.
eNeuro ; 3(2)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27257618

RESUMO

EPSPs occur when the neurotransmitter glutamate binds to postsynaptic receptors located on small pleomorphic membrane protrusions called dendritic spines. To transmit the synaptic signal, these potentials must travel through the spine neck and the dendritic tree to reach the soma. Due to their small size, the electrical behavior of spines and their ability to compartmentalize electrical signals has been very difficult to assess experimentally. In this study, we developed a method to perform simultaneous two-photon voltage-sensitive dye recording with two-photon glutamate uncaging in order to measure the characteristics (amplitude and duration) of uncaging-evoked EPSPs in single spines on the basal dendrites of L5 pyramidal neurons in acute brain slices from CD1 control mice. We were able to record uncaging-evoked spine potentials that resembled miniature EPSPs at the soma from a wide range of spine morphologies. In proximal spines, these potentials averaged 13.0 mV (range, 6.5-30.8 mV; N = 20) for an average somatic EPSP of 0.59 mV, whereas the mean attenuation ratio (spine/soma) was found to be 25.3. Durations of spine EPSP waveforms were found to be 11.7 ms on average. Modeling studies demonstrate the important role that spine neck resistance (Rneck) plays in spine EPSP amplitudes. Simulations used to estimate Rneck by fits to voltage-sensitive dye measurements produced a mean of 179 MΩ (range, 23-420 MΩ; N = 19). Independent measurements based on fluorescence recovery after photobleaching of a cytosolic dye from spines of the same population of neurons produced a mean R eck estimate of 204 MΩ (range, 52-521 MΩ; N = 34).


Assuntos
Córtex Cerebral/citologia , Espinhas Dendríticas/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Células Piramidais/ultraestrutura , Animais , Animais Recém-Nascidos , Biofísica , Simulação por Computador , Estimulação Elétrica , Feminino , Ácido Glutâmico/metabolismo , Técnicas In Vitro , Masculino , Camundongos , Modelos Neurológicos , Técnicas de Patch-Clamp , Fotodegradação , Imagens com Corantes Sensíveis à Voltagem
3.
J Gastrointest Oncol ; 3(4): 314-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23205307

RESUMO

Endoscopic ultrasound (EUS) is considered the most accurate tool for the TNM staging of esophageal cancer, but its role in early Barrett's neoplasia is still debatable. The aim was to evaluate the utility of EUS in Barrett's patients prior to therapy. Retrospective review of 109 patients enrolled in a treatment protocol for Barrett's neoplasia in our institution. EUS assessment was classified as suspicious for invasion in 19 patients; 84% of them had no evidence of invasion in final pathology. The assessment of depth of invasion of Barrett's neoplasia based solely on EUS findings leads to overstaging in most patients.

4.
World J Gastrointest Endosc ; 3(9): 171-82, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21954414

RESUMO

Esophageal adenocarcinoma is the most rapidly increasing cancer in western countries. High-grade dysplasia (HGD) arising from Barrett's esophagus (BE) is the most important risk factor for its development, and when it is present the reported incidence is up to 10% per patient-year. Adenocarcinoma in the setting of BE develops through a well known histological sequence, from non-dysplastic Barrett's to low grade dysplasia and then HGD and cancer. Endoscopic surveillance programs have been established to detect the presence of neoplasia at a potentially curative stage. Newly developed endoscopic treatments have dramatically changed the therapeutic approach of BE. When neoplasia is confined to the mucosal layer the risk for developing lymph node metastasis is negligible and can be successfully eradicated by an endoscopic approach, offering a curative intention treatment with minimal invasiveness. Endoscopic therapies include resection techniques, also known as tissue-acquiring modalities, and ablation therapies or non-tissue acquiring modalities. The aim of endoscopic treatment is to eradicate the whole Barrett's segment, since the risk of developing synchronous and metachronous lesions due to the persistence of molecular aberrations in the residual epithelium is well established.

6.
Curr Biol ; 21(7): 527-38, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21458263

RESUMO

BACKGROUND: Biological networks experience quantitative change in response to environmental and evolutionary variation. Computational modeling allows exploration of network parameter space corresponding to such variations. The intercellular signaling network underlying Caenorhabditis vulval development specifies three fates in a row of six precursor cells, yielding a quasi-invariant 3°3°2°1°2°3° cell fate pattern. Two seemingly conflicting verbal models of vulval precursor cell fate specification have been proposed: sequential induction by the EGF-MAP kinase and Notch pathways, or morphogen-based induction by the former. RESULTS: To study the mechanistic and evolutionary system properties of this network, we combine experimental studies with computational modeling, using a model that keeps the network architecture constant but varies parameters. We first show that the Delta autocrine loop can play an essential role in 2° fate specification. With this autocrine loop, the same network topology can be quantitatively tuned to use in the six-cell-row morphogen-based or sequential patterning mechanisms, which may act singly, cooperatively, or redundantly. Moreover, different quantitative tunings of this same network can explain vulval patterning observed experimentally in C. elegans, C. briggsae, C. remanei, and C. brenneri. We experimentally validate model predictions, such as interspecific differences in isolated vulval precursor cell behavior and in spatial regulation of Notch activity. CONCLUSIONS: Our study illustrates how quantitative variation in the same network comprises developmental patterning modes that were previously considered qualitatively distinct and also accounts for evolution among closely related species.


Assuntos
Comunicação Autócrina , Padronização Corporal , Caenorhabditis/embriologia , Caenorhabditis/metabolismo , Transdução de Sinais , Animais , Evolução Biológica , Caenorhabditis/genética , Caenorhabditis elegans/metabolismo , Simulação por Computador , Indução Embrionária , Fator de Crescimento Epidérmico/metabolismo , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Receptor Notch1/metabolismo , Vulva/citologia , Vulva/embriologia
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