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Many critical biological processes, like wound healing, require densely packed cell monolayers/tissues to transition from a jammed solid-like to a fluid-like state. Although numerical studies anticipate changes in the cell shape alone can lead to unjamming, experimental support for this prediction is not definitive because, in living systems, fluidization due to density changes cannot be ruled out. Additionally, a cell's ability to modulate its motility only compounds difficulties since even in assemblies of rigid active particles, changing the nature of self-propulsion has non-trivial effects on the dynamics. Here, we design and assemble a monolayer of synthetic cell-mimics and examine their collective behaviour. By systematically increasing the persistence time of self-propulsion, we discovered a cell shape-driven, density-independent, re-entrant jamming transition. Notably, we observed cell shape and shape variability were mutually constrained in the confluent limit and followed the same universal scaling as that observed in confluent epithelia. Dynamical heterogeneities, however, did not conform to this scaling, with the fast cells showing suppressed shape variability, which our simulations revealed is due to a transient confinement effect of these cells by their slower neighbors. Our experiments unequivocally establish a morphodynamic link, demonstrating that geometric constraints alone can dictate epithelial jamming/unjamming.
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Forma Celular , Células Artificiais , Movimento Celular , Modelos Biológicos , Animais , Células Epiteliais , HumanosAssuntos
Adjuvantes Imunológicos , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Glândula Tireoide/diagnóstico por imagem , Tireoidite Autoimune , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , COVID-19/epidemiologia , ChAdOx1 nCoV-19/administração & dosagem , ChAdOx1 nCoV-19/efeitos adversos , Feminino , Humanos , Imunogenicidade da Vacina , Pessoa de Meia-Idade , Administração dos Cuidados ao Paciente/métodos , SARS-CoV-2 , Testes de Função Tireóidea/métodos , Tireoidite Autoimune/induzido quimicamente , Tireoidite Autoimune/diagnóstico , Tireoidite Autoimune/fisiopatologia , Tireoidite Autoimune/terapia , Tomografia Computadorizada de Emissão/métodos , Resultado do TratamentoRESUMO
BACKGROUND: Physical frailty as a measure of physiological reserve is an important yet understudied topic in necrotizing pancreatitis. We measured frailty metrics in patients with necrotizing pancreatitis at baseline and at 1 month to assess dynamic change. We hypothesized that greater baseline frailty and steeper decline in frailty biomarkers are associated with worse outcomes in necrotizing pancreatitis. METHODS: A retrospective analysis of an institutional, necrotizing pancreatitis-specific database was performed. First order outcomes were organ failure, infected necrosis, step-up approach failure, and mortality. Baseline frailty assessment included measurement of comorbid diseases (modified frailty index), nutritional status (prognostic nutritional index), and radiologic sarcopenia (psoas muscle index, Hounsfield unit average calculation). Dynamic frailty was evaluated using psoas muscle index and Hounsfield unit average calculation. Significant associations between baseline and dynamic frailty with outcomes were analyzed. RESULTS: Three hundred and forty-one patients were included in this study. Most patients were male (65%) with biliary etiology of necrotizing pancreatitis (46%). Baseline comorbid diseases and baseline sarcopenia were not associated with first order outcomes. Lower baseline prognostic nutritional index was associated with organ failure (P < .001) and infected necrosis (P < .001). After 30 days, 25% of patients became sarcopenic. Larger declines in all sarcopenia metrics were associated with organ failure, infected necrosis, and/or death (P < .05). Lower psoas area and density were independent risk factors for organ failure and infected necrosis. CONCLUSION: Dynamic changes in sarcopenia-focused frailty metrics were significantly and consistently associated with organ failure, infected necrosis, and death. Further development of a dynamic frailty index to objectively guide decision-making in necrotizing pancreatitis is warranted.
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Fragilidade/etiologia , Estado Nutricional , Pancreatite Necrosante Aguda/complicações , Pancreatite Necrosante Aguda/mortalidade , Sarcopenia/complicações , Adulto , Idoso , Comorbidade , Feminino , Humanos , Indiana/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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PURPOSE: The purpose of this prospective study was to evaluate the feasibility of positron emission tomography/computed tomography (PET/CT)-guided biopsy of Ga-68 avid lesions using an automated robotic arm and determine the diagnostic yield of this technique. MATERIAL AND METHODS: Patients who underwent Ga-68 labelled tracers imaging followed by PET/CT-guided biopsies of tracer-avid lesions were prospectively included. Biopsies were performed using a dedicated automated-robotic-arm assisted PET/CT-guided biopsy device on the same-day of diagnostic PET/CT-imaging. The tissue samples were retrieved after confirming the position of needle-tip in the target lesion. Procedure-related complications and radiation exposure of the interventionist were recorded. Histopathological reports were reviewed for diagnostic yield. RESULTS: A total of 25 patients (19 men, six women) with a mean age of 50.8±17.3 (SD) years (range: 17-83 years) were included. The biopsies were performed after PET/CT using Ga-68 DOTANOC (n=16) or Ga-68 PSMA (n=8) and Ga-68 chemokine-analogue (n=1). The biopsy samples were obtained from the liver (n=9), bone (n=8), lymph-nodes (n=3), lung (n=1), pancreas (n=1), anterior mediastinal lesion (n=1), peritoneal-deposit (n=1) and thigh-lesion (n=1). No immediate or delayed procedure-related complications were documented in any patient. PET/CT-guided molecular sampling was technically successful in all the patients. Histopathology revealed malignancies in all the biopsied specimens without the need for repeat sampling or further invasive-diagnostic workup, with a diagnostic yield of 100%. The estimated absorbed-radiation dose was 566.7µSv/year for the interventionist. CONCLUSION: PET/CT-guided molecular biopsy using Ga-68 labelled radiotracers is feasible and can be performed safely and accurately with a high-diagnostic yield. It is helpful in accurately staging the disease when tracer-avid isolated distant lesion evident on imaging and highly practical in patients with previous inconclusive sampling.
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Radioisótopos de Gálio , Biópsia Guiada por Imagem/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/instrumentação , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Robótica , Adulto JovemRESUMO
PURPOSE: Patients with stage III non-small-cell lung cancer (NSCLC) treated with chemoradiotherapy (CRT) in low- and middle-income countries (LMIC) continue to have a poor prognosis. It is known that FDG PET/CT improves staging, treatment selection and target volume delineation (TVD), and although its use has grown rapidly, it is still not widely available in LMIC. CRT is often used as sequential treatment, but is known to be more effective when given concurrently. The aim of the PERTAIN study was to assess the impact of introducing FDG PET/CT-guided concurrent CRT, supported by training and quality control (QC), on the overall survival (OS) and progression-free survival (PFS) of patients with stage III NSCLC. METHODS: The study included patients with stage III NSCLC from nine medical centres in seven countries. A retrospective cohort was managed according to local practices between January 2010 and July 2014, which involved only optional diagnostic FDG PET/CT for staging (not for TVD), followed by sequential or concurrent CRT. A prospective cohort between August 2015 and October 2018 was treated according to the study protocol including FDG PET/CT in treatment position for staging and multimodal TVD followed by concurrent CRT by specialists trained in protocol-specific TVD and with TVD QC. Kaplan-Meier analysis was used to assess OS and PFS in the retrospective and prospective cohorts. RESULTS: Guidelines for FDG PET/CT image acquisition and TVD were developed and published. All specialists involved in the PERTAIN study received training between June 2014 and May 2016. The PET/CT scanners used received EARL accreditation. In November 2018 a planned interim analysis was performed including 230 patients in the retrospective cohort with a median follow-up of 14 months and 128 patients in the prospective cohort, of whom 69 had a follow-up of at least 1 year. Using the Kaplan-Meier method, OS was significantly longer in the prospective cohort than in the retrospective cohort (23 vs. 14 months, p = 0.012). In addition, median PFS was significantly longer in the prospective cohort than in the retrospective cohort (17 vs. 11 months, p = 0.012). CONCLUSION: In the PERTAIN study, the preliminary results indicate that introducing FDG PET/CT-guided concurrent CRT for patients with stage III NSCLC in LMIC resulted in a significant improvement in OS and PFS. The final study results based on complete data are expected in 2020.
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Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Quimiorradioterapia , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Carcinoma Pulmonar de Células não Pequenas/terapia , Intervalo Livre de Doença , Estônia , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Índia , Jordânia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Paquistão , Estudos Prospectivos , Controle de Qualidade , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Resultado do Tratamento , Turquia , VietnãRESUMO
Anti-vascular endothelial growth factor (VEGF) therapy has demonstrated efficacy in treating human metastatic cancers, but therapeutic resistance is a practical limitation and most tumors eventually become unresponsive. To identify microenvironmental factors underlying the resistance of cancer to antiangiogenesis therapy, we conducted genomic analyses of intraperitoneal ovarian tumors in which adaptive resistance to anti-VEGF therapy (B20 antibody) developed. We found that expression of the microseminoprotein, prostate-associated (MSMP) gene was substantially upregulated in resistant compared with control tumors. MSMP secretion from cancer cells was induced by hypoxia, triggering MAPK signaling in endothelial cells to promote tube formation in vitro. Recruitment of the transcriptional repressor CCCTC-binding factor (CTCF) to the MSMP enhancer region was decreased by histone acetylation under hypoxic conditions in cancer cells. MSMP siRNA, delivered in vivo using the DOPC nanoliposomes, restored tumor sensitivity to anti-VEGF therapy. In ovarian cancer patients treated with bevacizumab, serum MSMP concentration increased significantly only in non-responders. These findings imply that MSMP inhibition combined with the use of antiangiogenesis drugs may be a new strategy to overcome resistance to antiangiogenesis therapy.
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Bevacizumab/farmacologia , Carcinoma Epitelial do Ovário/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias das Tubas Uterinas/patologia , Proteínas de Neoplasias/metabolismo , Neoplasias Peritoneais/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Apoptose , Biomarcadores Tumorais , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/metabolismo , Hipóxia Celular , Proliferação de Células , Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias das Tubas Uterinas/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Neovascularização Patológica , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/metabolismo , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Chronic pancreatitis (CP) leads to malabsorption and metabolic bone disease (MBD). Alcoholic CP (ACP) and tropical CP (TCP) are the two common types of CP. OBJECTIVE: We investigated the presence of occult MBD in patients with CP and compared the same between ACP and TCP. MATERIALS AND METHODS: In this cross-sectional, observational study, we included serial patients of CP in different stages and are grouped as ACP (Group 1; n = 67) and TCP (Group 2; n = 35). We determined serum calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D (25OHD), and intact parathyroid hormone (PTH) levels. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry in the neck of the left femur. MBD was defined by the presence of either low bone mass (Z-score Results: The study participants (85 males; 17 females) had a mean age of 40.8 ± 12.6 years, CP duration of 3.7 ± 4.7 years, and Body Mass Index of 22.5 ± 3.2 kg/m2. A total of 37 (36%) patients had MBD (osteomalacia in 31 and low bone mass in 6). The frequency of MBD was same in the TCP (16/35) and ACP (21/65) groups (P = 0.1940). Elevated PTH (>70 pg/mL) was seen in 14 patients with 25OHD deficiency and low calcium (<8.5 mg/dL) in 29 patients. BMD did not show a significant correlation with the duration of CP. CONCLUSION: Occult MBD is seen in a third of patients with CP and is similar irrespective of the etiology. The disease is silent and mandates active screening in all susceptible individuals.
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Fosfatase Alcalina/sangue , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico , Cálcio/sangue , Pancreatite Crônica/diagnóstico , Hormônio Paratireóideo/sangue , Vitamina D/análogos & derivados , Absorciometria de Fóton , Adulto , Índice de Massa Corporal , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteomalacia/epidemiologia , Pancreatite Crônica/sangue , Pancreatite Crônica/epidemiologia , Vitamina D/sangueRESUMO
BACKGROUND: A critical appraisal of the benefits of minimally invasive surgery (MIS) is needed, but is lacking. This study examined the associations between MIS and 30-day postoperative outcomes including complications graded according to the Clavien-Dindo classification, unplanned readmissions, hospital stay and mortality for five common surgical procedures. METHODS: Patients undergoing appendicectomy, colectomy, inguinal hernia repair, hysterectomy and prostatectomy were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Non-parsimonious propensity score methods were used to construct procedure-specific matched-pair cohorts that reduced baseline differences between patients who underwent MIS and those who did not. Bonferroni correction for multiple comparisons was applied and P < 0·006 was considered significant. RESULTS: Of the 532 287 patients identified, 53·8 per cent underwent MIS. Propensity score matching yielded an overall sample of 327 736 patients (appendicectomy 46 688, colectomy 152 114, inguinal hernia repair 59 066, hysterectomy 59 066, prostatectomy 10 802). Within the procedure-specific matched pairs, MIS was associated with significantly lower odds of Clavien-Dindo grade I-II, III and IV complications (P ≤ 0·004), unplanned readmissions (P < 0·001) and reduced hospital stay (P < 0·001) in four of the five procedures studied, with the exception of inguinal hernia repair. The odds of death were lower in patients undergoing MIS colectomy (P < 0·001), hysterectomy (P = 0·002) and appendicectomy (P = 0·002). CONCLUSION: MIS was associated with significantly fewer 30-day postoperative complications, unplanned readmissions and deaths, as well as shorter hospital stay, in patients undergoing colectomy, prostatectomy, hysterectomy or appendicectomy. No benefits were noted for inguinal hernia repair.
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Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Readmissão do Paciente , Complicações Pós-Operatórias/mortalidade , Apendicectomia/efeitos adversos , Apendicectomia/economia , Colectomia/efeitos adversos , Colectomia/economia , Gastos em Saúde , Herniorrafia/efeitos adversos , Herniorrafia/economia , Humanos , Histerectomia/efeitos adversos , Histerectomia/economia , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Readmissão do Paciente/economia , Complicações Pós-Operatórias/economia , Pontuação de Propensão , Prostatectomia/efeitos adversos , Prostatectomia/economia , Resultado do Tratamento , Estados UnidosRESUMO
BACKGROUND: To ascertain 3-year urinary continence (UC) and sexual function (SF) recovery following robot-assisted radical prostatectomy (RARP) for clinically high-risk prostate cancer (PCa). METHODS: Retrospective analyses of a prospectively maintained database for 769 patients with D'Amico high-risk PCa undergoing RARP at two tertiary care centers in the United States and Europe between 2001 and 2014. The association between time since RARP and recovery of UC (defined as 0 pad/one safety liner per day) and SF (defined as sexual health inventory for men (SHIM) score ⩾17) was tested in separate preoperative and post-operative Cox-proportional hazards regression models. Sensitivity analyses were conducted using continence 0 pad per day and erection sufficient for intercourse as end points for UC and SF recovery, respectively. RESULTS: Mean age of the cohort was 62.3 years, and 62.1% harbored ⩾PT3a disease. Nerve sparing (unilateral or bilateral) RARP was performed in 87.7% of patients. Kaplan-Meier estimates of UC recovery at 12, 24 and 36 months after surgery was 85.2%, 89.1% and 91.2%, respectively, while 33.8, 52.3 and 69.0% of preoperatively potent men (preoperative SHIM ⩾17; n=548; 71.3%) recovered SF. Similar results were noted in sensitivity analyses. Patient age and year of surgery were associated with UC and SF recovery; additionally, preoperative SHIM score, degree of nerve sparing, pT3b-T4 disease and surgical margins were associated with SF recovery over the period of observation. CONCLUSIONS: Patients with D'Amico high-risk PCa treated with RARP may continue to recover UC and SF beyond 12 months of surgery and show promising outcomes at 3-year follow-up. Appropriate patient selection and counseling may aid in setting realistic expectations for functional recovery post RARP.
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Disfunção Erétil/fisiopatologia , Prostatectomia/reabilitação , Neoplasias da Próstata/cirurgia , Procedimentos Cirúrgicos Robóticos/reabilitação , Idoso , Disfunção Erétil/reabilitação , Disfunção Erétil/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/reabilitação , Robótica , Resultado do Tratamento , Coletores de UrinaRESUMO
KRas is mutated in a significant number of human cancers and so there is an urgent therapeutic need to target KRas signalling. To target KRas in lung cancers we used a systems approach of integrating a genome-wide miRNA screen with patient-derived phospho-proteomic signatures of the KRas downstream pathway, and identified miR-193a-3p, which directly targets KRas. Unique aspects of miR-193a-3p biology include two functionally independent target sites in the KRas 3'UTR and clinically significant correlation between miR-193a-3p and KRas expression in patients. Rescue experiments with mutated KRas 3'UTR showed very significantly that the anti-tumour effect of miR-193a-3p is via specific direct targeting of KRas and not due to other targets. Ex vivo and in vivo studies utilizing nanoliposome packaged miR-193a-3p demonstrated significant inhibition of tumour growth, circulating tumour cell viability and decreased metastasis. These studies show the broader applicability of using miR-193a-3p as a therapeutic agent to target KRas-mutant cancer.
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Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias/genética , Neoplasias/patologia , Células Neoplásicas Circulantes/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Interferência de RNA , Regiões 3' não Traduzidas , Ciclo Celular , Linhagem Celular Tumoral , Bases de Dados Genéticas , Genes Reporter , Humanos , Metástase Neoplásica , Células Neoplásicas Circulantes/patologia , RNA Mensageiro/genéticaRESUMO
Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further.
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Inibidores da Angiogênese/metabolismo , Cistadenocarcinoma Seroso/prevenção & controle , Proteínas de Ligação a Ácido Graxo/antagonistas & inibidores , Neovascularização Patológica/prevenção & controle , Neoplasias Ovarianas/prevenção & controle , Animais , Apoptose , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Cistadenocarcinoma Seroso/irrigação sanguínea , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Seguimentos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Camundongos , Camundongos Nus , Gradação de Tumores , Invasividade Neoplásica , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Prognóstico , Estudos Prospectivos , Receptor Notch1/metabolismo , Transdução de Sinais , Taxa de Sobrevida , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: The utilization and extent of pelvic lymph node dissection (PLND) varies depending on the disease and practice patterns. AIMS: This study compares practice patterns in utilization of PLND between Indian and United States (US) practices. SETTINGS AND DESIGN: We focused on 415 patients (204 India; 211 US) prostate cancer patients treated with robot-assisted radical prostatectomy, between 2015 and 2016, within the Vattikuti Collective Quality Initiative database. SUBJECTS AND METHODS: Utilization of PLND and number of nodes removed were evaluated for the entire cohort, and after stratifying for Country of treatment and D'Amico risk groups. Logistic regression tested the relationship between PLND and country of treatment, after adjusting for disease risk. RESULTS: Indian patients had a higher risk distribution (D'Amico high-risk 53.4% in India vs. 27% in the US; P< 0.001) compared to their US counterparts. Overall, 193/204 (94.6%) Indian patients underwent PLND versus 181/211 (85.8%) US patients (P = 0.003). When stratified based on disease risk, PLND was performed more frequently in Indian patients with low-risk disease (81.0% vs. 41.4%,P= 0.008), but not in those with intermediate and high-risk disease. On multivariable analysis, Indian patients had a 2.57-fold higher probability of undergoing PLND than their US counterparts (P = 0.02). The analysis of the number of lymph nodes removed showed similar trends. CONCLUSIONS: Indian patients are more likely to undergo PLND than US patients. This is, especially true for patients with low-risk disease, who are unlikely to benefit from this procedure. Efforts should focus on optimizing the utilization of PLND, and deliver it only when there is clinical indication.
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Excisão de Linfonodo/métodos , Prostatectomia/métodos , Idoso , Bases de Dados Factuais , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados UnidosRESUMO
To investigate the mechanisms underlying our recent paradoxical finding that mitotically incapacitated and genomically unstable polyploid giant cancer cells (PGCCs) are capable of tumor initiation, we labeled ovarian cancer cells with α-tubulin fused to green fluorescent protein, histone-2B fused to red fluorescent protein and FUCCI (fluorescent ubiquitination cell cycle indicator), and tracked the spatial and time-dependent change in spindle and chromosomal dynamics of PGCCs using live-cell fluorescence time-lapse recording. We found that single-dose (500 nm) treatment with paclitaxel paradoxically initiated endoreplication to form PGCCs after massive cell death. The resulting PGCCs continued self-renewal via endoreplication and further divided by nuclear budding or fragmentation; the small daughter nuclei then acquired cytoplasm, split off from the giant mother cells and acquired competency in mitosis. FUCCI showed that PGCCs divided via truncated endoreplication cell cycle (endocycle or endomitosis). Confocal microscopy showed that PGCCs had pronounced nuclear fragmentation and lacked expression of key mitotic proteins. PGCC-derived daughter cells were capable of long-term proliferation and acquired numerous new genome/chromosome alterations demonstrated by spectral karyotyping. These data prompt us to conceptualize a giant cell cycle composed of four distinct but overlapping phases, initiation, self-renewal, termination and stability. The giant cell cycle may represent a fundamental cellular mechanism to initiate genomic reorganization to generate new tumor-initiating cells in response to chemotherapy-induced stress and contributes to disease relapse.
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The degree of tumor removal at surgery is a major factor in predicting outcome for ovarian cancer. A single multimodality agent that can be used with magnetic resonance (MR) for staging and pre-surgical planning, and with optical imaging to aid surgical removal of tumors, would present a new paradigm for ovarian cancer. We assessed whether a dual-mode, dual-Gadolinium (DM-Dual-Gd-ICG) contrast agent can be used to visualize ovarian tumors in the peritoneal cavity by multimodal MR and near infra-red imaging (NIR). Intraperitoneal ovarian tumors (Hey-A8 or OVCAR3) in mice enhanced on MR two days after intravenous DM-Dual Gd-ICG injection compared to controls (SNR, CNR, p < 0.05, n = 6). As seen on open abdomen and excised tumors views and confirmed by optical radiant efficiency measurement, Hey-A8 or OVCAR3 tumors from animals injected with DM-Dual Gd-ICG had increased fluorescence (p < 0.05, n = 6). This suggests clinical potential to localize ovarian tumors by MR for staging and surgical planning, and, by NIR at surgery for resection.
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Meios de Contraste/farmacologia , Gadolínio/farmacologia , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Imagem Óptica/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Animais , Feminino , Humanos , Lipossomos , Camundongos , Camundongos NusRESUMO
BACKGROUND: To study the prevalence of occult hepatitis B virus infection (OBI) in a tertiary care hospital. METHODS: 50 HBsAg negative individuals, each amongst blood donors, alcohol dependence syndrome (ADS), alcoholic cirrhotics, hepatitis C virus (HCV)/cryptogenic cirrhotics, end-stage renal disease (ESRD) on maintenance haemodialysis for one year, all malignancies prior to chemotherapy and HIV positive patients were evaluated for anti-HBc total antibody, and blood hepatitis B virus (HBV) DNA amplification in those tested positive. RESULTS: A total of 60/369 (16.2%) individuals were anti-HBc total positive, 13/50 (26%) of HCV/cryptogenic cirrhotics, 13/52 (25%) of HIV positive, 10/50 (20%) of patients with malignancy, 10/51 (19.6%) and 7/59 (11.9%) of alcoholic cirrhotics and ADS respectively had intermediate prevalence, while, blood donors 5/55 (9.1%), ESRD patients 2/52 (3.8%) had low prevalence. 12 patients (20% of all anti-HBc total positive cases) were HBV DNA positive, 5 HCV cirrhotics (10% of total HCV/cryptogenic), 4 HIV positive (7.69%), 1 each of ADS (1.69%), alcoholic cirrhotics (1.96%) and malignancy group (2%). Blood donors and ESRD patients were negative for HBV DNA. CONCLUSION: HBV DNA amplification may under diagnose OBI and anti-HBc total positivity may be a better surrogate marker. Nucleic acid testing of blood donors, however is preferred, especially in high endemic areas. OBI must be looked for in cirrhotics, HIV infection, and patients with cancers prior to chemotherapy, as they may contribute to morbidity in them.
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BACKGROUND: Evaluation of new surgical procedures is a complex process challenged by evolution of technique, operator learning curves, the possibility of variable procedural quality, and strong treatment preferences among patients and clinicians. Preliminary studies that address these issues are needed to prepare for a successful randomized trial. The IDEAL (Idea, Development, Exploration, Assessment and Long-term follow-up) Framework and Recommendations provide an integrated step-by-step evaluation pathway that can help investigators achieve this. METHODS: A practical guide was developed for investigators evaluating new surgical interventions in the earlier phases before a randomized trial (corresponding to stages 1, 2a and 2b of the IDEAL Framework). The examples and practical tips included were chosen and agreed upon by consensus among authors with experience either in designing and conducting IDEAL format studies, or in helping others to design such studies. They address the most common challenges encountered by authors attempting to follow the IDEAL Recommendations. RESULTS: A decision aid has been created to help identify the IDEAL stage of an innovation from literature reports, with advice on how to design and report the IDEAL study formats discussed, along with the ethical and scientific rationale for specific recommendations. CONCLUSION: The guide helps readers and researchers to understand and implement the IDEAL Framework and Recommendations to improve the quality of evidence supporting surgical innovation.
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Medicina Baseada em Evidências/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Procedimentos Cirúrgicos Operatórios , HumanosRESUMO
Non-invasive characterization of adrenal lesions is a commonly encountered diagnostic challenge. Characteristic clinical and correlative imaging findings may assist in only arriving at a probable diagnosis. Currently, (18)F-FDG PET/CT is considered to provide the most comprehensive imaging information. We here present a case of bilateral adrenal tuberculosis that highlights the need for caution during the interpretation of (18)F-FDG PET/CT and also the need to suggest histopathological correlation.
Assuntos
Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Doenças das Glândulas Suprarrenais/microbiologia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Tuberculose Endócrina/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
MicroRNAs (miRNAs) are small RNA molecules that affect cellular processes by controlling gene expression. Recent studies have shown that hypoxia downregulates Drosha and Dicer, key enzymes in miRNA biogenesis, causing a decreased pool of miRNAs in cancer and resulting in increased tumor growth and metastasis. Here we demonstrate a previously unrecognized mechanism by which hypoxia downregulates Dicer. We found that miR-630, which is upregulated under hypoxic conditions, targets and downregulates Dicer expression. In an orthotopic mouse model of ovarian cancer, delivery of miR-630 using 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanoliposomes resulted in increased tumor growth and metastasis, and decreased Dicer expression. Treatment with the combination of anti-miR-630 and anti-vascular endothelial growth factor antibody in mice resulted in rescue of Dicer expression and significantly decreased tumor growth and metastasis. These results indicate that targeting miR-630 is a promising approach to overcome Dicer deregulation in cancer. As demonstrated in the study, use of DOPC nanoliposomes for anti-miR delivery serves as a better alternative approach to cell line-based overexpression of sense or antisense miRNAs, while avoiding potential in vitro selection effects. Findings from this study provide a new understanding of miRNA biogenesis downregulation observed under hypoxia and suggest therapeutic avenues to target this dysregulation in cancer.