University of Nebraska Omaha

About: University of Nebraska Omaha is a education organization based out in Omaha, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4526 authors who have published 8905 publications receiving 213914 citations. The organization is also known as: UNO & University of Omaha.

Posttransplantation lymphoproliferative disorders in bone marrow transplant recipients are aggressive diseases with a high incidence of adverse histologic and immunobiologic features.

Abstract: Posttransplantation lymphoproliferative disorders (PT-LPDs) occurring in T-cell depleted (TCD) allogeneic bone marrow transplant recipients seem to be different from those that arise in solid organ recipients in their early development, the high incidence of extensive dissemination at presentation, and their aggressive course and high fatality rate. We report a series of 10 patients with PT-LPDs after TCD allogeneic bone marrow transplant. We studied the correlation between the morphology of the lesions; their clonality based on immunoglobulin (Ig) heavy chain gene rearrangement analysis and immunohistochemistry; their proliferative activity as measured by immunoperoxidase staining for the proliferating cell nuclear antigen (PCNA) and the presence of p53 gene product overexpression. Histologically, our cases corresponded to the two morphologic categories of polymorphic B-cell lymphoma (PBCL, seven cases) and malignant lymphoma immunoblastic (ML-IB, three cases). Ig light-chain staining showed monoclonality in a minority of the cases, whereas Ig gene rearrangement analysis by polymerase chain reaction revealed B-cell clonality in three of seven cases of PBCL and in all three cases of ML-IB. The Epstein-Barr virus (EBV) genome, the expression of EBV latent membrane protein or both were found in all 10 specimens. High proliferative activity (PCNA > or = 66%) was found in all cases, with a mean PCNA value of 56% in PBCL and 84% in ML-IB. Five specimens were p53+ (two of seven PBCL and three of three ML-IB). Two of four PBCL cases resolved with the administration of donor leukocytes. All of the remaining patients died of the PT-LPD within a short time from admission. Our results show that the PT-LPDs after TCD bone marrow transplantation are characterized by a high frequency of high-grade histologic subtypes, frequent monoclonality, high proliferative activity, frequent overexpression of p53 gene product, and poor prognosis. These characteristics observed in only a minority of cases of PT-LPDs occurring after solid organ transplantation may account for the less aggressive clinical behavior observed in those diseases.

Improved twin support vector machine

Abstract: We improve the twin support vector machine (TWSVM) to be a novel nonparallel hyperplanes classifier, termed as ITSVM (improved twin support vector machine), for binary classification. By introducing the different Lagrangian functions for the primal problems in the TWSVM, we get an improved dual formulation of TWSVM, then the resulted ITSVM algorithm overcomes the common drawbacks in the TWSVMs and inherits the essence of the standard SVMs. Firstly, ITSVM does not need to compute the large inverse matrices before training which is inevitable for the TWSVMs. Secondly, different from the TWSVMs, kernel trick can be applied directly to ITSVM for the nonlinear case, therefore nonlinear ITSVM is superior to nonlinear TWSVM theoretically. Thirdly, ITSVM can be solved efficiently by the successive overrelaxation (SOR) technique or sequential minimization optimization (SMO) method, which makes it more suitable for large scale problems. We also prove that the standard SVM is the special case of ITSVM. Experimental results show the efficiency of our method in both computation time and classification accuracy.

Suicide and older African‐American women

Abstract: Suicide is rare among older African American women. This article describes a study in which reasons for this phenomenon were explored. A study of attitudes toward suicide was conducted with a sampl...