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991.
Kaposi sarcoma-associated herpesvirus in non-Hodgkin lymphoma and reactive lymphadenopathy in Uganda
Engels EA Mbulaiteye SM Othieno E Gomez M Mathew S Cesarman E Knowles DM Chadburn A 《Human pathology》2007,38(2):308-314
Kaposi sarcoma-associated herpesvirus (KSHV) causes Kaposi sarcoma and is also associated with primary effusion lymphoma, a subset of diffuse large B-cell lymphomas, and multicentric Castleman disease. Because KSHV infection is endemic in sub-Saharan Africa, we sought to identify cases of KSHV-positive non-Hodgkin lymphomas (NHLs) and reactive lymphadenopathy in this region. One hundred forty-four cases (80 NHLs, 64 reactive lymph nodes) from the major pathology laboratory in Uganda were reviewed. One NHL was KSHV-positive, as indicated by staining for the viral latent nuclear antigen. This NHL was a diffuse large B-cell lymphoma in a 5-year-old boy. The tumor was also Epstein-Barr virus-positive. In addition, 2 reactive lymph nodes, both classified histologically as follicular involution, stained KSHV latent nuclear antigen-positive and thus most likely represent multicentric Castleman disease. In all 3 KSHV-positive cases, a minority of cells expressed KSHV viral interleukin 6, a biologically active cytokine homolog. In conclusion, we show that KSHV is rarely associated with lymphoproliferative disorders in sub-Saharan Africa. We describe the first case of a KSHV-positive NHL from this region; this case is also the first reported pediatric lymphoma associated with KSHV infection. 相似文献
992.
Prediction of children's reading skills using behavioral, functional, and structural neuroimaging measures 总被引:1,自引:0,他引:1
Hoeft F Ueno T Reiss AL Meyler A Whitfield-Gabrieli S Glover GH Keller TA Kobayashi N Mazaika P Jo B Just MA Gabrieli JD 《Behavioral neuroscience》2007,121(3):602-613
The ability to decode letters into language sounds is essential for reading success, and accurate identification of children at high risk for decoding impairment is critical for reducing the frequency and severity of reading impairment. We examined the utility of behavioral (standardized tests), and functional and structural neuroimaging measures taken with children at the beginning of a school year for predicting their decoding ability at the end of that school year. Specific patterns of brain activation during phonological processing and morphology, as revealed by voxel-based morphometry (VBM) of gray and white matter densities, predicted later decoding ability. Further, a model combining behavioral and neuroimaging measures predicted decoding outcome significantly better than either behavioral or neuroimaging models alone. Results were validated using cross-validation methods. These findings suggest that neuroimaging methods may be useful in enhancing the early identification of children at risk for poor decoding and reading skills. 相似文献
993.
Norris EH Uryu K Leight S Giasson BI Trojanowski JQ Lee VM 《The American journal of pathology》2007,170(2):658-666
The factors initiating or contributing to the pathogenesis of Parkinson's disease and related neurodegenerative synucleinopathies are still largely unclear, but environmental factors such as pesticides have been implicated. In this study, A53T mutant human alpha-synuclein transgenic mice (M83), which develop alpha-synuclein neuropathology, were treated with the pesticides paraquat and maneb (either singly or together), and their effects were analyzed. Immunohistochemical and biochemical analyses showed that chronic treatment of M83 transgenic mice with both pesticides (but not with either pesticide alone) drastically increased neuronal alpha-synuclein pathology throughout the central nervous system including the hippocampus, cerebellum, and sensory and auditory cortices. alpha-Synuclein-associated mitochondrial degeneration was observed in M83 but not in wild-type alpha-synuclein transgenic mice. Because alpha-synuclein inclusions accumulated in pesticide-exposed M83 transgenic mice without a motor phenotype, we conclude that alpha-synuclein aggregate formation precedes disease onset. These studies support the notion that environmental factors causing nitrative damage are closely linked to mechanisms underlying the formation of alpha-synuclein pathologies and the onset of Parkinson's-like neurodegeneration. 相似文献
994.
Favaloro EJ Wong RC Jovanovich S Roberts-Thomson P 《American journal of clinical pathology》2007,127(3):441-448
We evaluated the results of lgG beta2-glycoprotein-I (B2GPI) antibody assays in a multilaboratory setting by analyzing data from an external quality assurance program for the 2003 through 2005 cycles for 27 serum samples, including quantitative IgG-B2GPI values and qualitative interpretation and grading (ie, negative or positive; grade of positivity), according to method type and in conjunction with clinical data. We report high interlaboratory variation in numeric IgG-B2GPI results, comparable to that reported for IgG anticardiolipin antibody (aCL) testing, and some method-based variation. For example, interlaboratory coefficients of variation for IgG-B2GPI were more than 50% in 19 samples (70%). For qualitative reporting, there was generally better consensus than previously reported for semiquantitative IgG-aCL testing; although 100% consensus occurred for only 11 samples (41%), more than 90% of laboratories agreed for 19 samples (70%). In some cases, laboratory findings (negative or positive IgG-B2GPI) did not agree with clinical information. Despite the lack of formal standardization for IgG-B2GPI testing compared with IgG-aCL, there seems to be better cross-laboratory consensus. Improvement in standardization of these assays is still required to improve interlaboratory and intermethod concordance of results and interpretation between laboratories and the clinical usefulness of IgG-B2GPI testing. 相似文献
995.
Rouse DJ Caritis SN Peaceman AM Sciscione A Thom EA Spong CY Varner M Malone F Iams JD Mercer BM Thorp J Sorokin Y Carpenter M Lo J Ramin S Harper M Anderson G;National Institute of Child Health Human Development Maternal-Fetal Medicine Units Network 《The New England journal of medicine》2007,357(5):454-461
996.
Okie S 《The New England journal of medicine》2007,356(20):2017-2021
997.
Moseley KL Freed GL Bullard CM Goold SD 《Journal of the National Medical Association》2007,99(1):15-21
BACKGROUND: African Americans' mistrust of healthcare is often cited as a cause of racial disparities in health and has been linked to cultural mistrust. African-American parents' level of cultural mistrust while in a general healthcare setting has not been previously measured. OBJECTIVE: To determine the performance, participant acceptance, feasibility of administration and demographic associations of a measure of cultural mistrust, the Cultural Mistrust Inventory (CMI), in African-American parents seeking healthcare. METHODS: A cross-sectional sample of 69 self-identified African-American parents of minor children recruited in a university-affiliated, urban pediatric/family practice outpatient clinic completed an anonymous, self-administered questionnaire containing demographic items and the CMI. RESULTS: The response rate was 91% (n=63), and 49 (78%) -- answered all questions. Measured mistrust did not vary with gender, insurance or education. The CMI's internal consistency was similar to previously published studies of the instrument (alpha=0.92). Parents indicating discomfort with the CMI's questions reported significantly less mistrust than parents who did not indicate discomfort (p=0.01). CONCLUSIONS: The CMI is feasible to administer in a clinic setting and demonstrates good internal consistency. It can be a useful tool to assess the effect of cultural mistrust on the healthcare decisions African-American parents make for their children. However, when measuring cultural mistrust in a healthcare setting, respondents' comfort with the survey questions should be assessed. 相似文献
998.
Hager-Theodorides AL Rowbotham NJ Outram SV Dessens JT Crompton T 《European journal of immunology》2007,37(2):487-500
Expression of TCRbeta and pre-TCR signalling are essential for differentiation of CD4- CD8- double negative (DN) thymocytes to the CD4+ CD8+ double-positive (DP) stage. Thymocyte development in adult Rag1, Rag2 or TCRbetadelta-deficient mice is arrested at the DN3 stage leading to the assumption that pre-TCR signalling and beta-selection occur at, and are obligatory for, the transition from DN3 to DN4. We show that the majority of DN3 and DN4 cells that differentiate during early embryogenesis in wild-type mice do not express intracellular (ic) TCRbeta/gammadelta. These foetal icTCRbeta-/gammadelta- DN4 cells were T lineage as determined by expression of Thy1 and icCD3 and TCRbeta DJ rearrangement. In addition, in the foetal Rag1-/- thymus, a normal percentage of DN4 cells were present. In wild-type mice after hydrocortisone-induced synchronisation of differentiation, the majority of DN4 cells that first emerged did not express icTCRbeta/gammadelta, showing that adult thymocytes can also differentiate to the DN4 stage independently of pre-TCR signalling. Pre-TCR signalling induced expansion in the DN4 population, but lack of TCRbeta/gammadelta expression did not immediately induce apoptosis. Our data demonstrate in vivo differentiation from DN3 to DN4 cell in the absence of TCRbeta/gammadelta expression in the foetal thymus, and after hydrocortisone treatment of adult mice. 相似文献
999.
Charles Miller Roxanne Karimi Susan Silbernagel Danielle Kostrubiak Frederick Schiavone Qiao Zhang 《Archives of environmental & occupational health》2018,73(4):251-257
Mercury (Hg), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) concentrations differ across seafood types. Our aim was to investigate the association of Hg, EPA, and DHA, as well as avid consumption of diverse seafood types, with cardiovascular variables heart rate variability (HRV) and QT interval duration (QTc) in a contemporary population. We measured HRV and QTc by Holter monitor, EPA and DHA in plasma, total Hg in whole blood, and possible confounders in 94 avid seafood consumers from Long Island, NY. Participants had mean Hg of 8.4 mcg/L, mean EPA of 1.2%, and mean DHA of 3.7% of total fatty acids. Adjusted for possible confounders, EPA+DHA, Hg, and total seafood consumption were not associated with HRV or QTc. Associations with consumption of specific seafood types were suggested (eg, tuna steak with QTc and anchovies with HRV) but require verification. 相似文献
1000.
Sabrina Iuglio Habib Chaudhury Susan E. Slaughter Christina Lengyel Jill Morrison 《Journal of nutrition in gerontology and geriatrics》2018,37(2):82-104
Long-term care (LTC) physical and psychosocial mealtime environments have been inconsistently assessed due to the lack of a standardized measure. The purpose of this study was to examine the construct validity of a new standardized observational measure, the Mealtime Scan (MTS), using the Making Most of Mealtimes data collected on 639 residents in 82 dining rooms in 32 LTC homes. The MTS includes physical, social, and person-centered care summary scales scored from 1 to 8. Mean ratings on these summary scales were moderate for physical (5.6 SD 0.9), social (5.0 SD 0.9), and person-centered care (PCC; 5.5 SD 0.8). Regression analyses determined which items within the MTS were associated with these summary scales: physical – music (B?=?0.27, p?=?0.04), number of staff passing food (B?=??0.11, p?=?0.03), number of residents (B?=??0.03, p?=?0.01); social – social sound (B?= 0.31 p?0.0001), number of residents requiring eating assistance (B?=?0.11, p?=?0.02); PCC – lighting (B?=?0.01 p?=?0.04), and total excess noise (B?=?0.05, p?0.0001). The Mealtime Relational Care Checklist (M-RCC) was associated positively with ratings on all three summary scales. Correlations revealed that the MTS summary scales were associated with other constructs: Dining Environment Audit Protocol functionality scale, resident and dining room level M-RCC, Mini Nutritional Assessment- Short Form, and resident Cognitive Performance Scale. These results demonstrate that the MTS summary scales exhibit construct validity, as the ratings were associated with expected observed mealtime characteristics and correlated with dining room and resident level constructs in anticipated directions. 相似文献