True conversive hallucinations

A case of true conversive hallucinations in a 19-year-old female soldier is described. This phenomenon is rare and should be distinguished from psychotic or dissociative states.     

Brain neurons and glial cells express Neu differentiation factor/heregulin: a survival factor for astrocytes.

Neu differentiation factor (NDF, also called heregulin) was isolated from mesenchymal cells on the basis of its ability to elevate phosphorylation of ErbB proteins. Earlier in situ hybridization analysis showed that NDF was transcribed predominantly in the central nervous system during embryonic development. To gain insights into the role of NDF in brain we analyzed its distribution by immunohistochemistry and in situ hybridization. Late-gestation (day 17) rat embryos displayed high NDF immunoreactivity in both motor (e.g., putamen) and limbic (e.g., septum) regions. Lower levels of the factor were exhibited by adult brain, except for the cerebellum, where NDF expression was increased postnatally. Both neurons and glial cells were identified by immunohistochemistry as NDF-producing cells (e.g., pyramidal neurons in the cerebral cortex and glial cells in the corpus callosum). By establishment of primary cultures of rat brain cells we confirmed that NDF was expressed in neurons as well as in astrocytes. In addition, by using such primary cultures we observed that NDF treatment exerted only a limited mitogenic effect, which was accompanied by significant acceleration of astrocyte maturation. Furthermore, long-term incubation with the factor specifically protected astrocytes from apoptosis, implying that NDF functions in brain as a survival and maturation factor for astrocytes.     

Initiator and recruited T lymphocytes are distinct subclasses of T lymphocytes.

In previous studies we found that the generation of a cell-mediated immune reaction required interaction between sensitized initiator T lymphocytes (ITL) and syngeneic recruited T lymphocytes (RTL). ITL were sensitized in vitro against allogeneic mouse fibroblasts and injected into a footpad of syngeneic recipient mice. ITL were observed to migrate from the connective tissues of the footpad to the draining popliteal lymph node (PLN). Sensitized ITL recruited RTL from the blood circulation into the PLN. This recruitment led to the generation of immunospecific effector and memory lymphocytes. In the present study we investigated the cellular characteristics of ITL and RTL. We found that both ITL and RTL were positive for Thy-1 antigen, and were absent from B mice. However, ITL and RTL differed in their response to various treatments. ITL were sensitive to adult thymectomy and resistant to antithymocyte serum (ATS). RTL were resistant to adult thymectomy and sensitive to ATS. Sensitized ITL were adherent to nylon wool or histamine-rabbit serum albumin-Sepharose, while RTL were not retained on such columns. ITL and RTL also differed in their relative distributions in various lymphoid organs and migratory pathways. The thymus demonstrated ITL but not RTL activity. In contrast, lymph node lymphocytes were a rich source of RTL, but had no detectable ITL activity. Both ITL and RTL could be demonstrated in the spleen. Thus, ITL and RTL functions are mediated by distinct subclasses of T lymphocytes which reside in particular compartments of the immune system.     

Recruitment of effector lymphocytes by initiator lymphocytes. In vivo migration of in vitro sensitized initiator T lymphocytes.

We previously found that mouse T lymphocytes sensitized in vitro against allo- or syngeneic fibroblasts, upon injection into syngeneic recipients, do not themselves differentiate into effector cells, but recruit effector T lymphocytes within the draining lymph nodes. As a result of sensitization, these initiator lymphocytes acquire a trypsin-sensitive membrane property which is necessary for recruitment. We now report studies on the in vivo migratory behavior of initiator lymphocytes following sensitization. We injected 51Cr-labeled initiator lymphocytes into recipient footpads and found significantly increased migration of sensitized cells to the draining popliteal lymph node (PLN) during the first day. By amputation of the foot at various times, we showed that migration during the first 12-24 hours was critical for subsequent recruitment. Trypsin treatment of initiator lymphocytes abolished this accelerated migration. Lymphocytes triggered nonspecifically by Con A migrated to the PLN like antigen-sensitized cells. We also compared the migration of injected lymphocytes from the footpad to the PLN in graft-versus-host and host-versus-graft reactions, and found these reactions to differ both from each other and from recruitment in terms of lymphocyte migration. These findings are discussed in terms of the physiology of the cell-mediated immune response and the notion of peripheral sensitization.     

Monoclonal antibodies against receptor for epidermal growth factor induce early and delayed effects of epidermal growth factor.

Mice were immunized with human epidermoid carcinoma cells (A-431 cell line) that possess an unusually high number of membrane receptors for epidermal growth factor (EGF). Spleen cells from these mice were fused with NSI cells, a nonsecreting murine myeloma. The immunoglobulins secreted by the obtained hybridomas were screened for specific binding to A-431 cells and selected according to their ability to inhibit the binding of radiolabeled EGF to the membrane of A-431 cells. Several antibodies secreted by cloned hybrid lines were found to inhibit the binding of radiolabeled EGF to membrane receptors of living A-431 cells, human foreskin fibroblasts, and mouse 3T3 fibroblasts and also to membrane preparations from A-431 cells. These monoclonal antibodies induced the early and delayed biological effects mediated by EGF. Like EGF, the antibodies induced morphological changes in A-431 cells and enhanced the phosphorylation of endogenous membrane proteins in membranes from these cells. They also stimulated DNA synthesis in human foreskin fibroblasts. These observations support the notion that the biological information of the EGF-receptor complex resides in the membrane receptor. Furthermore, the antibodies offer a powerful tool to study the structure, processing, and mode of action of EGF receptors.     

The in-vitro effect of fibrinogen, factor XIII and thrombin-activatable fibrinolysis inhibitor on clot formation and susceptibility to tissue plasminogen activator-induced fibrinolysis in hemodilution model

Patients suffering major traumatic or surgical bleeding are often exposed to hemodilution resulting in dilutional coagulopathy. The aim of this study was to evaluate in vitro the effects of fibrinogen, factor XIII and thrombin-activatable fibrinolysis inhibitor (TAFI) on clot formation and resistance to fibrinolysis in hemodilution conditions. Citrated whole blood from 36 healthy volunteers was diluted to 30 and 60% with lactated Ringer's solution. Blood samples were subsequently supplemented with fibrinogen, FXIII, TAFI or their combinations. Rotation thromboelastometry (ROTEM) in whole blood and thrombin generation in plasma were performed in the presence of CaCl? and tissue factor/EXTEM reagent, and fibrinolysis was induced by tissue plasminogen activator (tPA). Hemodilution was expressed by decrease of peak height in thrombin generation and α-angle and maximum clot firmness (MCF) in ROTEM. Fibrinogen, FXIII or TAFI did not correct the decrease in thrombin generation peak height. In ROTEM, spiking of diluted blood with fibrinogen stimulated clot propagation. In tPA-treated blood fibrinogen, FXIII and TAFI increased clot firmness and inhibited fibrinolysis. Stronger protection against fibrinolysis was achieved combining FXIII with TAFI. Hemodilution was associated with inhibition of thrombin generation; however, this effect was not sensitive to blood spiking with fibrinogen, FXIII and TAFI. In ROTEM, these hemostasis agents improved clot strength and decreased clot susceptibility to tPA in nondiluted and to more extent in diluted blood. The maximal protection against fibrinolysis was caused by TAFI. Combining FXIII with TAFI exerted synergistic inhibitory effect on fibrinolysis.     

Educational lectures enhance knowledge about the human immunodeficiency virus (HIV) and reduce risky behavior and fear among methadone maintenance treatment patients

Abstract

Background: The aim of this study was to characterize human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS)-related knowledge and stigma among methadone maintenance treatment (MMT) patients and evaluate the contribution of an educational lecture in reducing risky behavior and unjustified overprotective behavior due to fear and stigma among MMT patients. Methods: Patients from an MMT clinic within a tertiary medical center were invited to an educational lecture on HIV/AIDS. Seventy participants (of current 330) were chosen by a random sample (December 2015), plus at-risk patients and HIV patients. Attendee compliance and change in scores of questionnaires on knowledge (modified HIV-K-Q-22) and on sexual and injection behaviors were studied. Results: Forty-six patients (65.7% compliance) attended the lecture, and their knowledge and behavior scores improved 2?weeks post-lecture (knowledge: from 14.2?±?3 to 19.0?±?2.2 [P?<?.0005], sexual behavior: from 12.1?±?2.9 to 8.8?±?3.0 [P?<?.0005], and injection behavior: from 7.3?±?6.2 to 0.2?±?1.3 [P?<?.0005]). The unjustified fear of proximity to HIV carriers reported by 50% attendees fell to 35% post-lecture. Eight months post-lecture, the scores on knowledge and risky behavior of 21 randomly chosen attendees were still better than pre-lecture scores (knowledge: 15.4?±?2.3 vs. 17.2?±?1.8 [paired t test, P?=?.001], sexual behavior: 13.2?±?2.3 vs. 9.7?±?2.9 [P?<?.0005], and injection behavior: 9.3?±?5.6 vs. 2.8?±?3.1 [P?<?.0005]). Drug abuse and treatment adherence were not related to intervention and to risky behavior. Conclusions: More knowledge, less fear, and less risky behavior immediately and at 8?months post-lecture reflect the success and importance of the educational intervention. Future efforts are needed in order to reduce ignorance and fear associated with HIV/AIDS.