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1.
Gut ; 68(1): 94-100, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29066576

RESUMO

BACKGROUND: In general, academic but not community endoscopists have demonstrated adequate endoscopic differentiation accuracy to make the 'resect and discard' paradigm for diminutive colorectal polyps workable. Computer analysis of video could potentially eliminate the obstacle of interobserver variability in endoscopic polyp interpretation and enable widespread acceptance of 'resect and discard'. STUDY DESIGN AND METHODS: We developed an artificial intelligence (AI) model for real-time assessment of endoscopic video images of colorectal polyps. A deep convolutional neural network model was used. Only narrow band imaging video frames were used, split equally between relevant multiclasses. Unaltered videos from routine exams not specifically designed or adapted for AI classification were used to train and validate the model. The model was tested on a separate series of 125 videos of consecutively encountered diminutive polyps that were proven to be adenomas or hyperplastic polyps. RESULTS: The AI model works with a confidence mechanism and did not generate sufficient confidence to predict the histology of 19 polyps in the test set, representing 15% of the polyps. For the remaining 106 diminutive polyps, the accuracy of the model was 94% (95% CI 86% to 97%), the sensitivity for identification of adenomas was 98% (95% CI 92% to 100%), specificity was 83% (95% CI 67% to 93%), negative predictive value 97% and positive predictive value 90%. CONCLUSIONS: An AI model trained on endoscopic video can differentiate diminutive adenomas from hyperplastic polyps with high accuracy. Additional study of this programme in a live patient clinical trial setting to address resect and discard is planned.


Assuntos
Pólipos Adenomatosos/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia , Aprendizado Profundo , Competência Clínica , Diagnóstico Diferencial , Humanos , Imagem de Banda Estreita/métodos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Gravação em Vídeo
2.
Echocardiography ; 35(1): 17-23, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29160919

RESUMO

BACKGROUND: There is a growing interest in appropriate use criteria (AUC) for cardiovascular imaging referrals in Europe. These criteria, developed by American subspecialty societies, have been in use since 2007 and show a temporal reduction in inappropriate transthoracic echocardiogram (TTE) requests. When applied to European centers, inappropriate referral rates as high as 15% have been observed. METHODS: A retrospective analysis of TTE referrals for appropriateness and major abnormality detection was conducted over a two-month period at Cork University Hospital (CUH). RESULTS: Overall, 1277 requests were assessed, of which 97.7% were classifiable. Of the 1235 classifiable studies, 1049 (84.9%) were appropriate, 135 (10.9%) were inappropriate, and 51 (4.1%) were uncertain. Main indications were the evaluation of cardiac structure and function (496, 40.2%), hypertension, heart failure or cardiomyopathy (349, 28.3%), and valvular function (228, 18.5%). Inappropriate referral rates were significantly higher for outpatients compared to inpatients (13.8% vs 7.1%, P < .05) and cardiologist referrals compared to noncardiologists (13.1 vs 8.0%, P < .05), while one in three requests for the evaluation of valvular function (32.5%) were inappropriate. Compared to inappropriate studies, appropriate and uncertain scans had a greater prevalence of ≥1 major abnormalities (33.6% vs 19.3%, P < .001) and greater detection rates of new abnormalities (27.6% vs 13.3%, P < .001). CONCLUSION: Application of the 2011 AUC yields similar results to those reported from the US. The application of said criteria to our center could avoid one of every ten scans currently ordered.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Ecocardiografia/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Centros Médicos Acadêmicos , Europa (Continente) , Humanos , Estudos Retrospectivos
3.
Cleft Palate Craniofac J ; 55(9): 1277-1281, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29578807

RESUMO

OBJECTIVES: Numerous scales assessing the aesthetics of cleft lip repair exist. Most, including the Asher-McDade scale, use frontal and lateral views, while neglecting a basal view. We believe this view is important for properly assessing the aesthetics of repair. In this study, we evaluate the basal view in comparison to the Asher-McDade scale. METHODS: This scale was based on progressive columellar shortening and alar flaring/slumping. A panel of 4 plastic surgeons applied the basal and Asher-McDade scales to pictures of patients with repaired unilateral cleft lip in 56 multiethnic participants aged 5 years to 18 years; images were scored from 1 to 5 (best). Statistical analysis was done via Spearman correlation. RESULTS: Scores from plastic surgeons correlated strongly for each view. There was moderate correlation for the basal view with both nasal form and deviation scores ( P < .05). As expected, there were no strong correlations between the basal view and vermillion border or profile. DISCUSSION: The Asher-McDade scale has been used to evaluate cleft lift repairs but is limited due to its subjective nature. The basal view scale grades these repairs by using a scale of progressive columellar shortening and alar flaring/slumping, which provides an opportunity for quantification and standardization. Our results show that the basal view correlates with the Asher-McDade scale among raters, thus providing an objective and validated measure of cleft lip repair.


Assuntos
Atitude do Pessoal de Saúde , Fenda Labial/cirurgia , Estética , Avaliação de Resultados em Cuidados de Saúde , Adolescente , Criança , Pré-Escolar , Fenda Labial/etnologia , Feminino , Humanos , Masculino , Fotografação , Reprodutibilidade dos Testes , Resultado do Tratamento
4.
Ir J Med Sci ; 188(3): 873-877, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30560341

RESUMO

BACKGROUND: Registry data for total hip arthroplasty (THA) has allowed optimal fixation methods, bearing surfaces and many other factors to be assessed. We describe 10-year THA outcomes from an Irish perspective using regional THA registry data for the first time. AIMS: We assess the main predictors of revision in primary total hip arthroplasty (THA) using regional registry data. METHODS: This was a prospective study of registry data from a National Orthopaedic Hospital for all THAs with 10-year follow-up data. All metal-on-metal THAs and resurfacings were excluded from the analysis. All-cause revision was the primary outcome. Univariate and multivariate analyses controlling for confounding variables were performed to assess predictor impact on primary and secondary outcomes. RESULTS: A total of 1697 THAs were performed in 1553 patients. The three significant predictors for all-cause revision were fixation type (p < 0.01), surface bearing type (p < 0.01) and femoral head size (p < 0.05). The lowest 10-year all-cause revision rates were seen in cemented THRs at 1.2%. Ceramic-on-poly bearings had the lowest revision rate at 0.9%. The 22.225-mm head sizes had a significantly lower revision rate than other head sizes (p < 0.05). The causes for revision in order of decreasing frequency were infection (0.7%), dislocation (0.4%), periprosthetic fracture (0.2%) and aseptic loosening (0.1%). There were two re-revisions at 10 years in total. CONCLUSIONS: Based on this registry and other emerging registry data, the shift towards uncemented THAs may not be fully supported. We also acknowledge that ceramic-on-polyethylene bearings afford the lowest revision rates in this registry.


Assuntos
Artroplastia de Quadril/métodos , Sistema de Registros/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
Pain Physician ; 21(5): E523-E532, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30282400

RESUMO

BACKGROUND: The growth of interventional pain medicine in recent years has resulted in more procedures being carried out under fluoroscopic guidance. The proximity of the pain physician (PP) to ionization radiation (IR) potentially increases the risk of radiation exposure to the ocular region. A European directive has reduced the limits of occupational ocular dose 7.5-fold. OBJECTIVES: The objectives of this study are to quantify the typical IR exposure in the ocular region of PP and to compare it to recommended international guidelines. STUDY DESIGN: Three consultants involved in the pain unit service were enrolled in the study to reflect the dose implications involved with different caseloads, training obligations, and procedure types. All 3 consultants were experienced primary operators. SETTING: The study was undertaken at the pain management suite in the South Infirmary Victoria University Hospital (SIVUH). Annually, this unit performs 2,800 fluoroscopic guide pain procedures. METHODS: Thermoluminescent dosimeters (TLDs) calibrated to measure eye lens doses [Hp (0.07)] and whole-body doses (WBDs) were fitted to 3 pain consultants while they undertook imaging-guided pain procedures using mobile C-arm fluoroscopy over a 3-month period. The duration of radiation exposure, screening time (seconds), and procedure type were recorded. Radiation dose was calculated to estimate the effective radiation dose to the ocular region using (i) dose-area product (DAP) in milliGray per centimeter squared (mGycm2) and (ii) Air Kerma (AK) values in mGy. RESULTS: IR doses were effectively recorded in 682 cases over 3 months and the data extrapolated. The estimated annual lens dose experienced by pain physicians performing fluoroscopy-guided procedures is less than the recommended international guidelines. A significant linear relationship between screening time and IR exposure was estimated (rs = 0.93, P < 0.01). LIMITATIONS: In many centers, including our own, fluoroscopy procedures are undertaken by nonconsultant staff. Therefore, a small single-center cohort recruiting experienced consultant staff and not including pain fellows or registrars/residents with varying levels of experience is a limitation. CONCLUSION: While IR to the ocular region was significantly less than the recommended European safety guidelines, the annual dose needs to be confirmed in pain physicians with a lesser degree of clinical experience. KEY WORDS: Ionizing radiation, ocular, radiation protection, pain medicine, interventional.


Assuntos
Olho/efeitos da radiação , Exposição Ocupacional/análise , Médicos , Exposição à Radiação , Radiografia Intervencionista/efeitos adversos , Estudos de Coortes , Fluoroscopia/efeitos adversos , Fluoroscopia/métodos , Humanos , Exposição Ocupacional/efeitos adversos , Doses de Radiação , Proteção Radiológica , Radiação Ionizante , Radiografia Intervencionista/métodos
6.
BMJ Case Rep ; 20172017 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-28433984

RESUMO

Haemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal, haematological disorder, which can be clinically challenging to diagnose and manage. We report a case of HLH in a previously healthy 33-year-old primigravida. The patient presented at 22 weeks gestation with dyspnoea, abdominal pain, anaemia, thrombocytopenia and elevated liver enzymes suggestive of HELLP syndrome.HELLP, a syndrome characterised by haemolysis, elevated liver enzymes and low platelets is considered a severe form of pre-eclampsia. Despite delivery of the fetus, her condition deteriorated over 3-4 days with high-grade fever, worsening thrombocytopenia and anaemia requiring transfusion support. A bone marrow biopsy showed haemophagocytosis and a diagnosis of HLH was made. Partial remission was achieved with etoposide-based chemotherapy and complete remission following bone marrow transplantation. Eleven months post-transplant, the disease aggressively recurred, and the patient died within 3 weeks of relapse.


Assuntos
Etoposídeo/uso terapêutico , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/terapia , Adulto , Transplante de Medula Óssea , Diagnóstico Diferencial , Evolução Fatal , Feminino , Síndrome HELLP/patologia , Humanos , Gravidez
7.
Ann N Y Acad Sci ; 973: 555-8, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12485928

RESUMO

Increased expression of the type I insulin-like growth factor receptor (IGF-1R) is associated with colon cancer, while the antioxidant N-acetyl-l-cysteine (NAC) is known to suppress colonic proliferation. We demonstrate that NAC down-regulates the expression of IGF-1R on three colorectal adenocarcinoma cell lines (HT29, SW480, and LoVo). NAC also abrogates the proliferative effect of IGF-I on HT29 cells. This indicates a novel mechanism for the therapeutic effects of NAC.


Assuntos
Acetilcisteína/farmacologia , Anticarcinógenos/farmacologia , Receptor IGF Tipo 1/genética , Adenocarcinoma , Divisão Celular/efeitos dos fármacos , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células Tumorais Cultivadas
9.
Proc Natl Acad Sci U S A ; 102(43): 15294-8, 2005 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-16129826

RESUMO

Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.


Assuntos
Evolução Biológica , Hominidae/psicologia , Violência , Agressão , Animais , Arqueologia , Etnologia
10.
Expert Opin Ther Targets ; 9(5): 1031-44, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16185156

RESUMO

Fas is a transmembrane receptor that can induce apoptosis after cross-linking with either agonistic antibodies or with Fas ligand (FasL). Although originally described as an important regulator of peripheral immune homeostasis, accumulating evidence suggests that the Fas/FasL system plays an important role in tumour development. In addition to its proapoptotic functions, accumulating evidence demonstrates that Fas can activate numerous nonapoptotic signalling pathways, and that activation of these pathways can result in increased tumourigenicity and metastasis. This review summarises the current understanding of the Fas/FasL system in tumorigenesis and discusses attempts to utilise the Fas/FasL system in the treatment of cancer.


Assuntos
Antineoplásicos/farmacologia , Proteína Ligante Fas/metabolismo , Neoplasias/tratamento farmacológico , Receptor fas/metabolismo , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/metabolismo
11.
Am J Gastroenterol ; 99(8): 1539-43, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15307874

RESUMO

OBJECTIVES: We previously reported the use of laser capture microdissection (LCM) and PCR to detect the presence of Mycobacterium paratuberculosis DNA in granulomas of patients with Crohn's disease. While this does not imply a cause-effect relationship, it may influence the disease process because bacterial DNA has immunomodulatory effects. The aim of this study was to determine whether DNA from nonmycobacterial commensals, such as Escherichia coli, is also increased in the granulomas of Crohn's disease. METHODS: Archival tissue from 15 surgical cases of Crohn's disease and 10 non-Crohn's granulomatous bowel disease controls were examined. Granulomas were isolated using LCM, and the extracted DNA was examined for presence of E. coli DNA by nested PCR amplification of a 135 base-pair segment of the uidA gene. RESULTS: E. coli DNA was detected in microdissected granulomas in 12/15 Crohn's disease patients and in 1/10 non-Crohn's control granulomas (p < 0.001). Also, E. coli DNA was detected in 8/15 Crohn's full-thickness sections and in 4/10 control full-thickness sections. CONCLUSIONS: E. coli DNA may be detected more frequently in Crohn's granulomas than in other non-Crohn's bowel granulomas. This may indicate a tendency for lumenal bacteria to colonize inflamed tissue, or may be due to increased uptake of bacterial DNA by gut antigen presenting cells. In light of previous detection of M. paratuberculosis DNA in Crohn's granulomas, the nonspecific nature of the type of bacterial DNA present in granulomas is evidence against any one bacterium having a significant causative role in Crohn's disease.


Assuntos
Doença de Crohn/microbiologia , DNA Bacteriano/análise , Escherichia coli/isolamento & purificação , Granuloma/microbiologia , Intestinos/microbiologia , Doença de Crohn/patologia , Humanos , Intestinos/patologia , Microdissecção , Microscopia Confocal , Reação em Cadeia da Polimerase
12.
J Cell Sci ; 115(Pt 23): 4469-82, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12414993

RESUMO

Assembly of muscle sarcomeres is a complex dynamic process and involves a large number of proteins. A growing number of these have regulatory functions and are transiently present in the myofibril. We show here that the novel tubulin-associated RING/B-box protein MURF2 associates transiently with microtubules, myosin and titin during sarcomere assembly. During sarcomere assembly, MURF2 first associates with microtubules at the exclusion of tyrosinated tubulin. Then, MURF2-labelled microtubules associate transiently with sarcomeric myosin and later with A-band titin when non-striated myofibrils differentiate into mature sarcomeres. Finally, MURF2 labelled microtubules disappear from the sarcomere after the incorporation of myosin filaments and the elongation of titin. This suggests that the incorporation of myosin into nascent sarcomeres and the elongation of titin require an active, microtubule-dependent transport process and that MURF2-associated microtubules play a role in the alignment and extension of nascent sarcomeres. MURF2 is expressed in at least four isoforms, of which a 27 kDa isoform is cardiac specific. A C-terminal isoform is generated by alternative reading frame use, a novelty in muscle proteins. In mature cardiac sarcomeres, endogenous MURF2 can associate with the M-band, and is translocated to the nucleus. MURF2 can therefore act as a transient adaptor between microtubules, titin and nascent myosin filaments, as well as being involved in signalling from the sarcomere to the nucleus.


Assuntos
Microtúbulos/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Miofibrilas/metabolismo , Miosinas/metabolismo , Proteínas Quinases/metabolismo , Actinas/metabolismo , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular , Linhagem Celular , Núcleo Celular/metabolismo , Clonagem Molecular , Conectina , Células HeLa , Humanos , Dados de Sequência Molecular , Proteínas Musculares/genética , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Ligação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sarcômeros/metabolismo
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