168 research outputs found

    Resection, including transplantation, for hepatoblastoma and hepatocellular carcinoma: Impact on survival

    Get PDF
    Long-term survival in children with primary hepatic malignancies can not be expected without complete tumor resection. In the last ten years we have treated 21 children with hepatocellular carcinoma (HCC) and 21 children with hepatoblastoma (HEP), with tumor extirpation our surgical goal. Operative treatment included partial hepatectomy ([PH] 20), either primary (10) or delayed (following chemotherapy) (10), total hepatectomy and orthotopic liver transplantation ([OLT] 13), or upper abdominal exenteration and multiple organ transplantation (2). Two patients had both PH and subsequent total hepatectomy and OLT. Overall survival was 48% ( 20 42), with 9 patients dying of progressive disease prior to removal of their tumor. HEP patient survival was 67% ( 14 21), including 2 of 6 who underwent primary PH, 7 of 8 who had delayed PH, and 5 of 6 who underwent OLT. Survival for the children with HCC was 29% ( 6 21), including 1 of 4 after primary PH, 1 of 2 following delayed PH, 3 of 7 following OLT, and 1 of 2 after exenteration and multiple organ transplantation. Preoperative chemotherapy facilitated removal of 10 initially unresectable tumors (8 HEP, 2 HCC) at a second-look procedure. Total hepatectomy and OLT markedly improved survival in patients with disease unresectable by standard methods. Partial hepatectomy, either primary or delayed, should be attempted in all children with hepatic malignancies. Total hepatectomy and OLT appears to be a viable adjunct in the treatment of childhood malignancies, and should be used for otherwise unresectable tumors as part of a carefully planned protocol. © 1992

    Seeing Tree Structure from Vibration

    Full text link
    Humans recognize object structure from both their appearance and motion; often, motion helps to resolve ambiguities in object structure that arise when we observe object appearance only. There are particular scenarios, however, where neither appearance nor spatial-temporal motion signals are informative: occluding twigs may look connected and have almost identical movements, though they belong to different, possibly disconnected branches. We propose to tackle this problem through spectrum analysis of motion signals, because vibrations of disconnected branches, though visually similar, often have distinctive natural frequencies. We propose a novel formulation of tree structure based on a physics-based link model, and validate its effectiveness by theoretical analysis, numerical simulation, and empirical experiments. With this formulation, we use nonparametric Bayesian inference to reconstruct tree structure from both spectral vibration signals and appearance cues. Our model performs well in recognizing hierarchical tree structure from real-world videos of trees and vessels.Comment: ECCV 2018. The first two authors contributed equally to this work. Project page: http://tree.csail.mit.edu

    Working with interpreters: how student behavior affects quality of patient interaction when using interpreters

    Get PDF
    Background: Despite the prevalence of medical interpreting in the clinical environment, few medical professionals receive training in best practices when using an interpreter. We designed and implemented an educational workshop on using interpreters as part of the cultural competency curriculum for second year medical students (MSIIs) at David Geffen School of Medicine at UCLA. The purpose of this study is two-fold: first, to evaluate the effectiveness of the workshop and second, if deficiencies are found, to investigate whether the deficiencies affected the quality of the patient encounter when using an interpreter. Methods: A total of 152 MSIIs completed the 3-hour workshop and a 1-station objective-structured clinical examination, 8 weeks later to assess skills. Descriptive statistics and independent sample t-tests were used to assess workshop effectiveness. Results: Based on a passing score of 70%, 39.4% of the class failed. Two skills seemed particularly problematic: assuring confidentiality (missed by 50%) and positioning the interpreter (missed by 70%). While addressing confidentiality did not have a significant impact on standardized patient satisfaction, interpreter position did. Conclusion: Instructing the interpreter to sit behind the patient helps sustain eye contact between clinician and patient, while assuring confidentiality is a tenet of quality clinical encounters. Teaching students and faculty to emphasize both is warranted to improve cross-language clinical encounters

    Successful management of a chylothorax in infancy using a pleurectomy

    Full text link
    The management of chylothorax is described in three infants. Because none of them had had a direct injury to the thoracic duct, it was suspected that the chylothoraces had a significant chance of recurrence after simple ligation of the duct. To avoid recurrence, formal stripping of the parietal pleura was performed using a technique not previously reported in the literature. The operation was simple to perform and resulted in resolution of the chylothorax in all infants. The three cases and details of the surgical procedure are described.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47151/1/383_2004_Article_BF00183755.pd

    Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

    Get PDF
    Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009), which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.Universidade Federal de São Paulo (UNIFESP) Departamento de MedicinaCentro Assistencial Cruz de MaltaUniversidade Federal de São Paulo (UNIFESP) Departamento de PediatriaUNIFESP, Depto. de MedicinaUNIFESP, Depto. de PediatriaSciEL

    Effective transvascular delivery of nanoparticles across the blood-brain tumor barrier into malignant glioma cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Effective transvascular delivery of nanoparticle-based chemotherapeutics across the blood-brain tumor barrier of malignant gliomas remains a challenge. This is due to our limited understanding of nanoparticle properties in relation to the physiologic size of pores within the blood-brain tumor barrier. Polyamidoamine dendrimers are particularly small multigenerational nanoparticles with uniform sizes within each generation. Dendrimer sizes increase by only 1 to 2 nm with each successive generation. Using functionalized polyamidoamine dendrimer generations 1 through 8, we investigated how nanoparticle size influences particle accumulation within malignant glioma cells.</p> <p>Methods</p> <p>Magnetic resonance and fluorescence imaging probes were conjugated to the dendrimer terminal amines. Functionalized dendrimers were administered intravenously to rodents with orthotopically grown malignant gliomas. Transvascular transport and accumulation of the nanoparticles in brain tumor tissue was measured <it>in vivo </it>with dynamic contrast-enhanced magnetic resonance imaging. Localization of the nanoparticles within glioma cells was confirmed <it>ex vivo </it>with fluorescence imaging.</p> <p>Results</p> <p>We found that the intravenously administered functionalized dendrimers less than approximately 11.7 to 11.9 nm in diameter were able to traverse pores of the blood-brain tumor barrier of RG-2 malignant gliomas, while larger ones could not. Of the permeable functionalized dendrimer generations, those that possessed long blood half-lives could accumulate within glioma cells.</p> <p>Conclusion</p> <p>The therapeutically relevant upper limit of blood-brain tumor barrier pore size is approximately 11.7 to 11.9 nm. Therefore, effective transvascular drug delivery into malignant glioma cells can be accomplished by using nanoparticles that are smaller than 11.7 to 11.9 nm in diameter and possess long blood half-lives.</p
    corecore