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991.
Li He Scott Taylor Catherine Costa Irene Grzer Julia Kalser Tong-Ming Fu Daniel Freed Dai Wang Xiaohong Cui Laura Hertel Michael A. McVoy 《Viruses》2022,14(7)
Human cytomegalovirus (CMV) utilizes different glycoproteins to enter into fibroblast and epithelial cells. A trimer of glycoproteins H, L, and O (gH/gL/gO) is required for entry into all cells, whereas a pentamer of gH/gL/UL128/UL130/UL131A is selectively required for infection of epithelial, endothelial, and some myeloid-lineage cells, but not of fibroblasts. Both complexes are of considerable interest for vaccine and immunotherapeutic development but present a conundrum: gH/gL-specific antibodies have moderate potency yet neutralize CMV entry into all cell types, whereas pentamer-specific antibodies are more potent but do not block fibroblast infection. Which cell types and neutralizing activities are important for protective efficacy in vivo remain unclear. Here, we present evidence that certain CMV strains have evolved polymorphisms in gO to evade trimer-specific neutralizing antibodies. Using luciferase-tagged variants of strain TB40/E in which the native gO is replaced by gOs from other strains, we tested the effects of gO polymorphisms on neutralization by monoclonal antibodies (mAbs) targeting four independent epitopes in gH/gL that are common to both trimer and pentamer. Neutralization of fibroblast entry by three mAbs displayed a range of potencies that depended on the gO type, a fourth mAb failed to neutralize fibroblast entry regardless of the gO type, while neutralization of epithelial cell entry by all four mAbs was potent and independent of the gO type. Thus, specific polymorphisms in gO protect the virus from mAb neutralization in the context of fibroblast but not epithelial cell entry. No influence of gO type was observed for protection against CMV hyperimmune globulin or CMV-seropositive human sera, suggesting that antibodies targeting protected gH/gL epitopes represent a minority of the polyclonal neutralizing repertoire induced by natural infection. 相似文献
992.
Luiz Eduardo Fonteles Ritt Rebeca Sadigursky Ribeiro Isabela Pilar Moraes Alves de Souza Joo Victor Santos Pereira Ramos Daniel Sadigursky Ribeiro Gustavo Freitas Feitosa Queila Borges de Oliveira Ricardo Stein Eduardo Sahade Darz 《Arquivos brasileiros de cardiologia》2022,118(6):1118
BackgroundThe New York Heart Association (NYHA) functional classification is the most commonly used classification system for heart failure (HF), whereas cardiopulmonary exercise testing (CPET) is the gold standard for functional status evaluation in HF.ObjectiveThis study aimed to analyze correlation and concordance between NYHA classes and CPET variables.MethodsHF patients with clinical indication for CPET and ejection fraction (EF) < 50% were selected. Correlation (Spearman coefficient) and concordance (kappa) between NYHA classification and CPET-based classifications were analyzed. A p < 0.05 was accepted as significant.ResultsIn total, 244 patients were included. Mean age was 56 ± 14 years, and mean EF was 35.5% ± 10%. Distribution of patients according to NYHA classification was 31.2%% class I, 48.3% class II, 19.2% class III, and 1.3% class IV. Correlation (r) between NYHA and Weber classes was 0.489 (p < 0.001), and concordance was 0.231 (p < 0.001). Correlation (r) between NYHA and ventilatory classes (minute ventilation/carbon dioxide production [VE/VCO2] slope) was 0.218 (p < 0.001), and concordance was 0.002 (p = 0.959). Spearman correlation between NYHA and CPET score classes was 0.223 (p = 0.004), and kappa concordance was 0.027 (p = 0.606).ConclusionThere was a moderate association between NYHA and Weber classes, although concordance was low. Ventilatory (VE/VCO2slope) and CPET score classes had a weak association and a low concordance with NYHA classes. 相似文献
993.
Yamada Shinichi Takahashi Shun Malchow Berend Papazova Irina Stöcklein Sophia Ertl-Wagner Birgit Papazov Boris Kumpf Ulrike Wobrock Thomas Keller-Varady Katriona Hasan Alkomiet Falkai Peter Wagner Elias Raabe Florian J. Keeser Daniel 《European archives of psychiatry and clinical neuroscience》2022,272(6):957-969
European Archives of Psychiatry and Clinical Neuroscience - Significant evidence links white matter (WM) microstructural abnormalities to cognitive impairment in schizophrenia (SZ), but the... 相似文献
994.
Daqian Wang Ji Qi Baoru Huang Elizabeth Noble Danail Stoyanov Jun Gao Daniel S. Elson 《Biomedical optics express》2022,13(4):2364
Smoke generated during surgery affects tissue visibility and degrades image quality, affecting surgical decisions and limiting further image processing and analysis. Polarization is a fundamental property of light and polarization-resolved imaging has been studied and applied to general visibility restoration scenarios such as for smog or mist removal or in underwater environments. However, there is no related research or application for surgical smoke removal. Due to differences between surgical smoke and general haze scenarios, we propose an alternative imaging degradation model by redefining the form of the transmission parameters. The analysis of the propagation of polarized light interacting with the mixed medium of smoke and tissue is proposed to realize polarization-based smoke removal (visibility restoration). Theoretical analysis and observation of experimental data shows that the cross-polarized channel data generated by multiple scattering is less affected by smoke compared to the co-polarized channel. The polarization difference calculation for different color channels can estimate the model transmission parameters and reconstruct the image with restored visibility. Qualitative and quantitative comparison with alternative methods show that the polarization-based image smoke-removal method can effectively reduce the degradation of biomedical images caused by surgical smoke and partially restore the original degree of polarization of the samples. 相似文献
995.
We describe a case of lipoma with osteochondroid metaplasia in the knee joint. Although the location of the lesion and radiographic
findings were unusual, computed tomography and magnetic resonance imaging were useful in characterizing adipose, cartilaginous
and osseous tissue components within the lesion.
Received: 12 October 2000 Revision requested: 3 November 2000 Revision received: 23 December 2000 Accepted: 28 December 2000 相似文献
996.
997.
Daniel B Ennis Frederick H Epstein Peter Kellman Lameh Fananapazir Elliot R McVeigh Andrew E Arai 《Magnetic resonance in medicine》2003,50(3):638-642
Diastolic and systolic left ventricular (LV) dysfunction often significantly contribute to disabling symptoms in familial hypertrophic cardiomyopathy (FHC). This study compares regional LV function (midwall circumferential strain) during systole and diastole in eight FHC patients and six normal volunteers (NVs) using MR tagging. A prospectively-gated fast gradient-echo sequence with an echo-train readout was modified to support complementary spatial modulation of magnetization (CSPAMM) tagging and full cardiac cycle data acquisition using the cardiac phase to order reconstruction (CAPTOR), thus providing tag persistence and data acquisition during the entire cardiac cycle. Total systolic strains in FHC patients were significantly reduced in septal and inferior regions (both P < 0.01). Early-diastolic strain rates were reduced in all regions of the FHC group (all P < 0.03). The combination of CSPAMM and CAPTOR allows regional indices of myocardial function to be quantified throughout the cardiac cycle. This technique reveals regional differences in systolic and diastolic impairment in FHC patients. 相似文献
998.
Dikken JL van de Velde CJ Gönen M Verheij M Brennan MF Coit DG 《Annals of surgical oncology》2012,19(8):2443-2451
Purpose
To evaluate the changes in the 7th edition American Joint Committee on Cancer (AJCC) staging system for stomach cancer compared to the 6th edition; to compare the predictive accuracy of the two staging systems.Methods
In a combined database containing 2,196 patients who underwent an R0 resection for gastric adenocarcinoma, differences between the two staging systems were evaluated and stage-specific survival estimates compared. Concordance probability and Brier scores were estimated for both systems to examine the predictive accuracy.Results
Nodal status cutoff values were changed, leading to a more even distribution for the redefined N1, N2, and N3 group. AJCC 6th edition stage II reflected a highly heterogeneous population, which is now adequately subdivided in the AJCC 7th edition into stages IIA, IIB, and IIIA. The predictive accuracy of N classification improved significantly as measured by concordance. Despite increased complexity, the predictive accuracy of AJCC 7th stage grouping was significantly worse than that of the AJCC 6th edition.Discussion
The increased complexity of the 7th edition staging system is accompanied by improvements in the predictive value of nodal staging as compared to the 6th edition, but it was no better in overall stage-specific predictive accuracy. Future refinements of the tumor, node, metastasis staging system should consider whether increased complexity is balanced by improved prognostic accuracy. 相似文献999.
Daniel E. Klingler James H. Johnson Thomas A. Williams 《Journal of clinical psychology》1977,33(3):658-661
The objective assessment of thought disorder in schizophrenia is problem matic in clinical psychology. Recently and individually administered instrument (WIST) was introduced as a brief, objective, and quantitative measure of schizophrenic thought processes. Possible shortcomings of the WIST are noted; experimental findings that concern extension to group testing conditions, convergent validity with another self-report measure of schizophrenia, and discriminant validity from intellectual level are presented. 相似文献
1000.
Daniel R. Budman E. Bruce Merchant Alfred D. Steinberg Bernard Doft M. Eric Gershwin Elaine Lizzio J. Patton Reeves 《Arthritis \u0026amp; Rheumatology》1977,20(3):829-833
Thirty-seven patients with criteria for systemic lupus erythematosus (SLE) and 18 normal controls were studied for their spontaneous background IgM antibody plaque-forming cell number to specific chemical haptens. Active SLE patients had significantly more plaque-forming cells in their peripheral blood to a total of five chemical determinants than did patients with inactive disease or controls. This increased number of plaque forming-cells correlated with depressed serum C3 levels by Spearman rank-order analysis. The finding of elevated numbers of spontaneous IgM plaque-forming cells to defined chemical haptens supports the concept that active SLE demonstrates a generalized increase in B-cell activity toward a variety of antigens. 相似文献