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1.
J Homosex ; : 1-26, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37405701

RESUMO

Research finds that sexual minority university students experience considerable psychological and emotional distress. Furthermore, a recent study at Brigham Young University (BYU)-a university affiliated with The Church of Jesus Christ of Latter-day Saints-found that suicidality prevalence and severity were twice as high among sexual minority students compared to their heterosexual peers. To better understand this finding, we interviewed ten sexual minority students at BYU who reported clinically significant current or previous suicidality. A coding team and auditors then analyzed and categorized the transcripts of these interviews using the Consensual Qualitative Research methodology. Five domains emerged related to suicidality among sexual minority students: deterrents from suicidal ideation and intent; contributors to suicidal ideation and intent; religious and spiritual experiences; experiences with BYU; and suggested improvements. We found patterns consistent with previous literature, including relational and belonging factors contributing to suicidality; we also found that certain doctrinal interpretations were related to increased suicidality. The primary improvement requested by participants was feeling better understood and accepted (rather than ignored or marginalized). We discuss study limitations (including small sample size and low generalizability,), future directions for research, and implications for religious university campuses.

2.
Macromol Rapid Commun ; 43(24): e2200487, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35822234

RESUMO

Incorporating dynamic covalent bonds into block copolymers provides useful molecular level information during mechanical testing, but it is currently unknown how the incorporation of these units affects the resultant polymer morphology. High-molecular-weight polyisobutylene-b-polystyrene block copolymers containing an anthracene/maleimide dynamic covalent bond are synthesized through a combination of postpolymerization modification, reversible addition-fragmentation chain-transfer polymerization, and Diels-Alder coupling. The bulk morphologies with and without dynamic covalent bond are characterized by atomic force microscopy  and small-angle X-ray scattering, which reveal a strong dependence on annealing time and casting solvent. Morphology is largely unaffected by the inclusion of the mechanophore. The high-molecular-weight polymers synthesized allow interrogation of a large range of polymer domain sizes.

3.
BMJ Case Rep ; 14(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108156

RESUMO

We present a case of a 70-year-old Caucasian woman with multisystem granulomatous disease involving her lungs, bones and lymph nodes. The patient initially presented with cervical lymphadenopathy and subsequently developed progressive breathlessness. Imaging revealed extensive mediastinal, hilar and intra-abdominal lymphadenopathy as well as bilateral pulmonary parenchymal infiltrates. Lymph node and lung biopsy confirmed non-necrotising granulomatous inflammation while a BAL showed scanty growth of Cryptococcus neoformans and moderate growth of Staphylococcus aureus The patient received intravenous ceftriaxone and had a good response to treatment. She also completed 3 months of oral fluconazole. Although a diagnosis of sarcoidosis was considered most likely, the patient was not initially started on systemic corticosteroids due to concern around possible infection and initial response to antimicrobials. However, her exercise tolerance gradually deteriorated. A craniofacial CT revealed multiple lytic lesions involving the skull and visualised cervical spine. Biopsy of a clivus lesion revealed non-necrotising granulomatous inflammation while fungal cultures and histopathological stains were negative. The patient was diagnosed with widespread sarcoidosis and she was initiated on prednisolone and methotrexate which led to marked clinical and radiological improvement.


Assuntos
Linfadenopatia , Sarcoidose , Idoso , Biópsia , Feminino , Granuloma/diagnóstico por imagem , Granuloma/tratamento farmacológico , Humanos , Pulmão , Sarcoidose/diagnóstico , Sarcoidose/diagnóstico por imagem
4.
Diabetes Care ; 43(12): 3034-3041, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33055138

RESUMO

OBJECTIVE: To use optical coherence tomography angiography (OCTA) to determine whether retinal microvascular parameters are associated with carotid arterial disease in people with type 2 diabetes. RESEARCH DESIGN AND METHODS: Participants (community-based) underwent detailed assessments including carotid ultrasonography and OCTA. Ultrasound images were assessed for mean intima-media thickness (IMT) and the presence of stenosis. OCTA image analysis provided measures of vessel density, foveal avascular zone (FAZ) area, blood flow areas, and retinal thickness. For each OCTA variable, the most parsimonious model was generated using generalized estimating equations, then ipsilateral and contralateral carotid disease-related variables were added to determine their significance. RESULTS: A total of 474 eyes from 261 participants (mean ± SD age 72.0 ± 9.3 years, 57.1% males, median diabetes duration 15.4 years [interquartile range 11.1-22.4]) were analyzed. When carotid variables were added to the most parsimonious models, the ipsilateral natural logarithm of common carotid artery IMT (coefficient -2.56 [95% CI -4.76, -0.35], P = 0.023) and presence of any ipsilateral stenosis (-0.82 [-1.48, -0.17], P = 0.014) were statistically significantly associated with a lower parafoveal density in the deep capillary plexus. A mean bifurcation IMT ≥1 mm was associated with a decreased vessel density in the 300-µm ring surrounding the FAZ (coefficient -0.79 [-1.50, -0.08], P = 0.030)). Contralateral carotid disease-related variables were also significantly associated with retinal microvascular parameters. CONCLUSIONS: This is the first study to show that carotid disease is an independent associate of retinal microvascular disease assessed by OCTA in type 2 diabetes. Appropriately intensive management of carotid disease may improve the retinal microcirculation.


Assuntos
Doenças das Artérias Carótidas/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Capilares/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/epidemiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/etiologia , Feminino , Angiofluoresceinografia/métodos , Humanos , Macula Lutea/irrigação sanguínea , Masculino , Microvasos/diagnóstico por imagem , Pessoa de Meia-Idade , Doenças Retinianas/diagnóstico , Doenças Retinianas/epidemiologia , Doenças Retinianas/etiologia , Tomografia de Coerência Óptica/métodos
5.
JSLS ; 21(3)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28890650

RESUMO

BACKGROUND AND OBJECTIVES: Studies have shown economic and clinical advantages of laparoscopic left-colon resections. Laparoscopic conversion to open is an important surgical outcome. We estimated conversion incidence, identified risk factors, and measured the clinical and economic impact. METHODS: In this retrospective study, we used the Premier Perspective database to analyze left-sided colectomies from 2009 to 2014. Operating room time (ORT), length of stay (LOS), total hospital cost (2014 U.S. dollars); along with incidence of in-hospital clinical outcomes (anastomotic leak surrogate [Leak], transfusion, and mortality) were evaluated. Multivariable models accounting for hospital clustering were used to identify conversion risk factors and analyze the effect of conversion on economic and clinical outcomes. RESULTS: A total of 41,417 patients: 8,468 left hemicolectomy and 32,949 sigmoidectomy were identified. Lap-Conversion incidence was 13.3% (95% CI, 12.9-13.7). Adjusted mean LOS (±SE) days was significantly lower for the Lap-Successful group (4.9 compared with Lap-Conversion 6.8 and Open-Planned 7.0), but Lap-Conversion and Open-Planned had similar LOS. Adjusted mean cost was higher for Lap-Conversion $20,165 compared to Open-Planned $18,797; but this difference was smaller than the cost savings for Lap-Successful $16,206 ± $219. Open-Planned had lower odds of Leak compared to Lap-Conversion. Open-Planned and Lap-Conversion had similar odds of transfusion and mortality. Conversion risk factors included inflammatory bowel disease and left-hemicolectomy. Colorectal specialists were associated with 38% decreased odds of conversion. CONCLUSIONS: Successful laparoscopic surgery was the most cost effective, with decreased LOS and odds of blood transfusion, leak surrogate, and mortality. Conversion was the most expensive and had increased odds of leak surrogate, but similar LOS compared to Open-Planned. The beneficial effect size of successful laparoscopic surgery was larger than the negative effect of conversion compared to Open-Planned.


Assuntos
Colectomia/economia , Colectomia/métodos , Conversão para Cirurgia Aberta/economia , Custos Hospitalares/estatística & dados numéricos , Laparoscopia/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Conversão para Cirurgia Aberta/estatística & dados numéricos , Análise Custo-Benefício , Feminino , Humanos , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Estados Unidos
6.
Stud Health Technol Inform ; 220: 295-300, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27046595

RESUMO

The Virtual Pediatric Airways Workbench (VPAW) is a patient-centered surgical planning software system targeted to pediatric patients with airway obstruction. VPAW provides an intuitive surgical planning interface for clinicians and supports quantitative analysis regarding prospective surgeries to aid clinicians deciding on potential surgical intervention. VPAW enables a full surgical planning pipeline, including importing DICOM images, segmenting the airway, interactive 3D editing of airway geometries to express potential surgical treatment planning options, and creating input files for offline geometric analysis and computational fluid dynamics simulations for evaluation of surgical outcomes. In this paper, we describe the VPAW system and its use in one case study with a clinician to successfully describe an intended surgery outcome.


Assuntos
Imageamento Tridimensional/métodos , Modelos Biológicos , Doenças Respiratórias/diagnóstico por imagem , Doenças Respiratórias/cirurgia , Cirurgia Assistida por Computador/métodos , Interface Usuário-Computador , Simulação por Computador , Feminino , Treinamento com Simulação de Alta Fidelidade/métodos , Humanos , Masculino , Pediatria/métodos , Cuidados Pré-Operatórios/métodos , Sistema Respiratório/diagnóstico por imagem , Sistema Respiratório/cirurgia
7.
Laryngoscope ; 126(5): 1225-31, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26226933

RESUMO

OBJECTIVES/HYPOTHESIS: Determine whether quantitative geometric measures and a computational fluid dynamic (CFD) model derived from medical imaging of children with subglottic stenosis (SGS) can be effective diagnostic and treatment planning tools. STUDY DESIGN: Retrospective chart and imaging review in a tertiary care hospital. METHODS: Computed tomography scans (n = 17) of children with SGS were analyzed by geometric and CFD methods. Polysomnograms (n = 15) were also analyzed. Radiographic data were age/weight flow normalized and were compared to an atlas created from radiographically normal airways. Five geometric, seven CFD, and five polysomnography measures were analyzed. Statistical analysis utilized a two-sample t test with Bonferroni correction and area under the curve analysis. RESULTS: Two geometric indices (the ratio of the subglottic to midtracheal airway, the percent relative reduction of the subglottic airway) and one CFD measure (the percent relative reduction of the hydraulic diameter of the subglottic airway) were significant for determining which children with SGS received surgical intervention. Optimal cutoffs for these values were determined. Polysomnography, the respiratory effort-related arousals index, was significant only prior to Bonferroni correction for determining which children received surgical intervention. CONCLUSIONS: Geometric and CFD variables were sensitive at determining which patients with SGS received surgical intervention. Discrete quantitative assessment of the pediatric airway was performed, yielding preliminary data regarding possible objective thresholds for surgical versus nonsurgical treatment of disease. This study is limited by its small, retrospective, single-institution nature. Further studies to validate these findings and possibly optimize treatment threshold recommendations are warranted. LEVEL OF EVIDENCE: 4 Laryngoscope, 126:1225-1231, 2016.


Assuntos
Laringoestenose/diagnóstico , Laringe/patologia , Criança , Pré-Escolar , Eletrodiagnóstico , Feminino , Humanos , Hidrodinâmica , Lactente , Laringoestenose/patologia , Laringoestenose/fisiopatologia , Laringoestenose/cirurgia , Laringe/fisiopatologia , Masculino , Modelos Biológicos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
8.
Neuro Oncol ; 18(3): 350-60, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26245525

RESUMO

BACKGROUND: Glioblastoma (GBM) is a fatal cancer that has eluded major therapeutic advances. Failure to make progress may reflect the absence of a human GBM model that could be used to test compounds for anti-GBM activity. In this respect, the development of brain tumor-initiating cell (BTIC) cultures is a step forward because BTICs appear to capture the molecular diversity of GBM better than traditional glioma cell lines. Here, we perform a comparative genomic and genetic analysis of BTICs and their parent tumors as preliminary evaluation of the BTIC model. METHODS: We assessed single nucleotide polymorphisms (SNPs), genome-wide copy number variations (CNVs), gene expression patterns, and molecular subtypes of 11 established BTIC lines and matched parent tumors. RESULTS: Although CNV differences were noted, BTICs retained the major genomic alterations characteristic of GBM. SNP patterns were similar between BTICs and tumors. Importantly, recurring SNP or CNV alterations specific to BTICs were not seen. Comparative gene expression analysis and molecular subtyping revealed differences between BTICs and GBMs. These differences formed the basis of a 63-gene expression signature that distinguished cells from tumors; differentially expressed genes primarily involved metabolic processes. We also derived a set of 73 similarly expressed genes; these genes were not associated with specific biological functions. CONCLUSIONS: Although not identical, established BTIC lines preserve the core molecular alterations seen in their parent tumors, as well as the genomic hallmarks of GBM, without acquiring recurring BTIC-specific changes.


Assuntos
Neoplasias Encefálicas/genética , Variações do Número de Cópias de DNA/genética , Genoma Humano , Glioblastoma/genética , Células-Tronco Neoplásicas/patologia , Idoso , Autoanticorpos/uso terapêutico , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Testes Genéticos , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
9.
Nat Commun ; 6: 6351, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25690954

RESUMO

While significant effort has been dedicated to the characterization of epigenetic changes associated with prenatal differentiation, relatively little is known about the epigenetic changes that accompany post-natal differentiation where fully functional differentiated cell types with limited lifespans arise. Here we sought to address this gap by generating epigenomic and transcriptional profiles from primary human breast cell types isolated from disease-free human subjects. From these data we define a comprehensive human breast transcriptional network, including a set of myoepithelial- and luminal epithelial-specific intronic retention events. Intersection of epigenetic states with RNA expression from distinct breast epithelium lineages demonstrates that mCpG provides a stable record of exonic and intronic usage, whereas H3K36me3 is dynamic. We find a striking asymmetry in epigenomic reprogramming between luminal and myoepithelial cell types, with the genomes of luminal cells harbouring more than twice the number of hypomethylated enhancer elements compared with myoepithelial cells.


Assuntos
Mama/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Mama/citologia , Ciclo Celular , Diferenciação Celular , Separação Celular , Cromatina/química , Imunoprecipitação da Cromatina , Ilhas de CpG , Epigenômica , Células Epiteliais/citologia , Éxons , Feminino , Citometria de Fluxo , Genoma Humano , Histonas/química , Humanos , Íntrons , Cariotipagem , MicroRNAs/metabolismo , Análise de Sequência de RNA , Transcrição Gênica
10.
Med Image Anal ; 18(4): 684-98, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24747271

RESUMO

Atlas-building from population data is widely used in medical imaging. However, the emphasis of atlas-building approaches is typically to estimate a spatial alignment to compute a mean/median shape or image based on population data. In this work, we focus on the statistical characterization of the population data, once spatial alignment has been achieved. We introduce and propose the use of the weighted functional boxplot. This allows the generalization of concepts such as the median, percentiles, or outliers to spaces where the data objects are functions, shapes, or images, and allows spatio-temporal atlas-building based on kernel regression. In our experiments, we demonstrate the utility of the approach to construct statistical atlases for pediatric upper airways and corpora callosa revealing their growth patterns. We also define a score system based on the pediatric airway atlas to quantitatively measure the severity of subglottic stenosis (SGS) in the airway. This scoring allows the classification of pre- and post-surgery SGS subjects and radiographically normal controls. Experimental results show the utility of atlas information to assess the effect of airway surgery in children.


Assuntos
Atlas como Assunto , Encéfalo/anatomia & histologia , Corpo Caloso/anatomia & histologia , Humanos , Lactente , Modelos Estatísticos , Sistema Respiratório/anatomia & histologia , Estatística como Assunto
11.
Dis Colon Rectum ; 57(3): 365-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24509461

RESUMO

BACKGROUND: Hemorrhoidectomy is considered by many to be a contaminated operation that requires antibiotic prophylaxis to lower the incidence of surgical site infection. In reality, little evidence exists to either support or refute the use of antibiotic prophylaxis in this setting. OBJECTIVE: This study aimed to determine if antibiotic prophylaxis is associated with reduced incidence of postoperative surgical site infection following hemorrhoidectomy. DESIGN: This is a retrospective database review. SETTING: This study was conducted at multiple institutions. PATIENTS: All patients undergoing hemorrhoidectomy with minimum 3-month follow-up were included. MAIN OUTCOME MEASURES: The primary outcome measure was the incidence of postoperative surgical site infection. RESULTS: Eight hundred fifty-two patients met the inclusion criteria (50.1% female; mean age, 50.0 ± 13.7 years). The prevalence of preoperative risk factors for surgical site infection included 7.7% with a smoking history, 2.5% with diabetes mellitus, 0.8% receiving steroids, and 0.2% with Crohn's disease. Surgery was performed predominately for 3-column prolapsed internal and mixed internal/external hemorrhoidal disease. All surgeries performed were closed hemorrhoidectomies. Antibiotic prophylaxis was used in a fewer number of cases (41.3% vs 58.7%). Overall, there were only 12 documented postoperative infections identified, producing an overall incidence of 1.4%. Of those patients who developed postoperative surgical site infections, 9 (75%) did not receive antibiotic prophylaxis (p = 0.25). On multivariate regression analysis, no perioperative risk factor was associated with an increased risk of developing a posthemorrhoidectomy surgical site infection. Conversely, there were no adverse antibiotic-related complications such as Clostridium difficile colitis or antibiotic-associated diarrhea in those receiving antibiotic prophylaxis. LIMITATIONS: This study was limited by the retrospective nature of the analysis. CONCLUSIONS: Postoperative surgical site infection is an exceedingly rare event following hemorrhoidectomy. Antibiotic prophylaxis does not reduce the incidence of postoperative surgical site infection, and its routine use appears unnecessary.


Assuntos
Antibioticoprofilaxia , Hemorroidectomia , Infecção da Ferida Cirúrgica/prevenção & controle , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia
12.
Macromol Rapid Commun ; 35(2): 186-192, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24214162

RESUMO

Activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) conditions utilizing a low concentration of catalyst are successfully applied for the preparation of well-defined poly(glycidyl methacrylate) without the addition of external reducing agents. The living character of polymerization is evidenced by successful chain extensions with methyl methacrylate and methyl acrylate, again, in the absence of additional reducing agents, yielding block copolymers. The epoxide groups in glycidyl methacrylate or the corresponding polymer can serve as an intrinsic reducing agent to continuously regenerate the Cu(I) -based ATRP activator from the Cu(II) halide complex present in the systems. The reactivity of various epoxides in the reduction of the Cu(II) Br2 complex of tris(2-pyridylmethyl)amine is compared.


Assuntos
Compostos de Epóxi/química , Polimerização , Substâncias Redutoras/química , Catálise , Cinética , Espectroscopia de Ressonância Magnética
13.
Am J Surg ; 207(4): 520-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24239525

RESUMO

BACKGROUND: The Model for End-Stage Liver Disease Sodium Model (MELD-Na) is a validated scoring system that uses bilirubin, international normalized ratio, serum creatinine, and sodium to predict mortality in cirrhotic patients awaiting liver transplantation. The aim of this study was to identify the utility of MELD-Na to predict patient outcomes, with and without liver disease, after elective colon cancer surgery. METHODS: A review of the American College of Surgeons National Surgical Quality Improvement Program database (2005 to 2010) was conducted to calculate risk-adjusted 30-day outcomes using regression modeling. RESULTS: A total of 10,842 patients (mean age, 68 years; 51% women) were included. MELD-Na scores were higher in men (10.2 vs 9.1, P < .001) and in open procedures (9.9 vs 9.1, P < .001). The overall complication and mortality rates were 26.3% and 3.3%, respectively. Incremental increases in MELD-Na score correlated with a 1.2% increase in mortality and a 1.1% increase in complications. On multivariate analysis, complications increased with MELD-Na score (odds ratio [OR], 1.05 per 1 point increase; 95% confidence interval [CI], 1.038 to 1.066). MELD-Na score was also associated with increased mortality (OR, 1.13; 95% CI, 1.1 to 1.16), along with ascites (OR, 5.7; 95% CI, 3.7 to 8.8) and corticosteroids (OR, 2.1; 95% CI, 1.3 to 3.3). CONCLUSIONS: Elevated preoperative MELD-Na score is significantly associated with worse outcomes after elective resection for colon cancer.


Assuntos
Colectomia/métodos , Neoplasias do Colo/cirurgia , Procedimentos Cirúrgicos Eletivos/métodos , Falência Hepática/epidemiologia , Medição de Risco/métodos , Idoso , Neoplasias do Colo/complicações , Neoplasias do Colo/epidemiologia , Feminino , Seguimentos , Humanos , Hepatopatias/diagnóstico , Falência Hepática/complicações , Falência Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Período Pós-Operatório , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
14.
J Biomech Eng ; 136(2): 021004, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24337168

RESUMO

Effectively addressing population-level variability within orthopedic analyses requires robust data sets that span the target population and can be greatly facilitated by statistical methods for incorporating such data into functional biomechanical models. Data sets continue to be disseminated that include not just anatomical information but also key mechanical data including tissue or joint stiffness, gait patterns, and other inputs relevant to analysis of joint function across a range of anatomies and physiologies. Statistical modeling can be used to establish correlations between a variety of structural and functional biometrics rooted in these data and to quantify how these correlations change from health to disease and, finally, to joint reconstruction or other clinical intervention. Principal component analysis provides a basis for effectively and efficiently integrating variability in anatomy, tissue properties, joint kinetics, and kinematics into mechanistic models of joint function. With such models, bioengineers are able to study the effects of variability on biomechanical performance, not just on a patient-specific basis but in a way that may be predictive of a larger patient population. The goal of this paper is to demonstrate the broad use of statistical modeling within orthopedics and to discuss ways to continue to leverage these techniques to improve biomechanical understanding of orthopedic systems across populations.


Assuntos
Articulações/fisiologia , Articulações/cirurgia , Modelos Biológicos , Modelos Estatísticos , Procedimentos Ortopédicos , Próteses e Implantes , Animais , Simulação por Computador , Humanos , Dinâmica Populacional , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
World J Gastroenterol ; 19(27): 4277-88, 2013 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-23885138

RESUMO

Despite multiple efforts aimed at early detection through screening, colon cancer remains the third leading cause of cancer-related deaths in the United States, with an estimated 51000 deaths during 2013 alone. The goal remains to identify and remove benign neoplastic polyps prior to becoming invasive cancers. Polypoid lesions of the colon vary widely from hyperplastic, hamartomatous and inflammatory to neoplastic adenomatous growths. Although these lesions are all benign, they are common, with up to one-quarter of patients over 60 years old will develop pre-malignant adenomatous polyps. Colonoscopy is the most effective screening tool to detect polyps and colon cancer, although several studies have demonstrated missed polyp rates from 6%-29%, largely due to variations in polyp size. This number can be as high as 40%, even with advanced (> 1 cm) adenomas. Other factors including sub-optimal bowel preparation, experience of the endoscopist, and patient anatomical variations all affect the detection rate. Additional challenges in decision-making exist when dealing with more advanced, and typically larger, polyps that have traditionally required formal resection. In this brief review, we will explore the recent advances in polyp detection and therapeutic options.


Assuntos
Neoplasias do Colo/diagnóstico , Neoplasias do Colo/terapia , Pólipos do Colo/diagnóstico , Pólipos do Colo/terapia , Colonoscopia/métodos , Adenoma/diagnóstico , Adenoma/terapia , Humanos , Mucosa Intestinal/patologia , Laparoscopia/métodos , Lesões Pré-Cancerosas , Recidiva , Resultado do Tratamento
16.
IEEE Trans Med Imaging ; 32(10): 1939-51, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23846465

RESUMO

Longitudinal imaging studies are frequently used to investigate temporal changes in brain morphology and often require spatial correspondence between images achieved through image registration. Beside morphological changes, image intensity may also change over time, for example when studying brain maturation. However, such intensity changes are not accounted for in image similarity measures for standard image registration methods. Hence, 1) local similarity measures, 2) methods estimating intensity transformations between images, and 3) metamorphosis approaches have been developed to either achieve robustness with respect to intensity changes or to simultaneously capture spatial and intensity changes. For these methods, longitudinal intensity changes are not explicitly modeled and images are treated as independent static samples. Here, we propose a model-based image similarity measure for longitudinal image registration that estimates a temporal model of intensity change using all available images simultaneously.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Animais , Encéfalo/anatomia & histologia , Encéfalo/citologia , Encéfalo/patologia , Macaca mulatta
17.
Proc IEEE Int Symp Biomed Imaging ; 2013: 1206-1209, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26929791

RESUMO

Young children with upper airway problems are at risk for hypoxia, respiratory insufficiency and long term morbidity. Computational models and quantitative analysis would reveal airway growth patterns and benefit clinical care. To capture expected growth patterns we propose a method to build a pediatric airway atlas as a function of age. The atlas is based on a simplified airway model in combination with kernel regression. We show experimental results on children with subglottic stenosis to demonstrate that our method is able to track and measure the stenosis in pediatric airways.

18.
Gastroenterol Rep (Oxf) ; 1(1): 58-63, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24759668

RESUMO

BACKGROUND: Patients with Crohn's disease (CD) are believed to have more aggressive anorectal abscess and fistula disease. We assessed the types of procedures performed and perioperative complications associated with the surgical management of anorectal abscess and fistula disease in patients with and without CD. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database (ACS-NSQIP, 2005-2010) was used to calculate 30-day outcomes using regression modeling, accounting for demographics, comorbidities and surgical procedures. ICD-9 codes for anorectal abscess or fistula were used for initial selection. Patients were then stratified, based on the presence or absence of underlying CD. Local procedures included incision and drainage of abscesses, fistulotomy and seton placement. Cutaneous fistulas were considered simple, while all others were classified as complex (-vaginal, -urethral and -vesical). RESULTS: A total of 7,218 patients (mean age 45 years; 64% male) met inclusion criteria, with underlying CD in 345 (4.8%). CD patients were more likely to have a seton placed (9.9 vs 8.2%, P < 0.001) and be on steroids (15.4 vs 4.3%, P < 0.001). Thirty-seven percent of CD patients underwent local procedures, while 46% had a proctectomy and 8% underwent diversion. Fistulotomy was more common in those without underlying CD (16 vs 11%, P < 0.001). The overall complication rate after local treatment was 4.9%, with no difference between patients with and without CD (7.7 vs 4.9%, P = 0.144). This was not affected by fistula type-simple (7.9 vs 3.9%, P = 0.194) vs complex (33 vs 7.1%, P = 0.21)-or when stratified by wound (3.8 vs 2.4%; P = 0.26) or systemic complications (3.8 vs 2.5%; P = 0.53). Yet, complications following emergency procedures were higher in patients with CD (21.4 vs 5.9%, P = 0.047). Factors significantly associated with increased complications were Crohn's disease (OR = 8.2), lack of functional independence (OR = 2.0), pre-operative weight loss (OR = 2.6) and pre-operative acute renal failure (OR = 5.6). Steroids were also associated with a 1.7-fold increase in complications, independent from CD. CONCLUSIONS: While most patients with anorectal abscess/fistula are treated with local procedures, proctectomy and diversion use is fairly common in those with underlying CD. Although complication rates following elective local procedures for anorectal abscess/fistula are similar in patients with and without CD, they are higher in patients on steroids and in CD patients undergoing emergent procedures.

19.
Med Image Comput Comput Assist Interv ; 16(Pt 3): 584-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24505809

RESUMO

Atlas-building from population data is widely used in medical imaging. However, the emphasis of atlas-building approaches is typically to compute a mean / median shape or image based on population data. In this work, we focus on the statistical characterization of the population data, once spatial alignment has been achieved. We introduce and propose the use of the weighted functional boxplot. This allows the generalization of concepts such as the median, percentiles, or outliers to spaces where the data objects are functions, shapes, or images, and allows spatio-temporal atlas-building based on kernel regression. In our experiments, we demonstrate the utility of the approach to construct statistical atlases for pediatric upper airways and corpora callosa revealing their growth patterns. Furthermore, we show how such atlas information can be used to assess the effect of airway surgery in children.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Modelos Anatômicos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Simulação por Computador , Interpretação Estatística de Dados , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Artigo em Inglês | MEDLINE | ID: mdl-23286141

RESUMO

Longitudinal imaging studies are frequently used to investigate temporal changes in brain morphology. Image intensity may also change over time, for example when studying brain maturation. However, such intensity changes are not accounted for in image similarity measures for standard image registration methods. Hence, (i) local similarity measures, (ii) methods estimating intensity transformations between images, and (iii) metamorphosis approaches have been developed to either achieve robustness with respect to intensity changes or to simultaneously capture spatial and intensity changes. For these methods, longitudinal intensity changes are not explicitly modeled and images are treated as independent static samples. Here, we propose a model-based image similarity measure for longitudinal image registration in the presence of spatially non-uniform intensity change.


Assuntos
Envelhecimento/patologia , Encéfalo/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Algoritmos , Animais , Haplorrinos , Aumento da Imagem/métodos , Estudos Longitudinais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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