Medically serious versus non-serious suicide attempts: relationships of lethality and intent to clinical and interpersonal characteristics.

BACKGROUND: The study of near-fatal suicide attempts may provide insight into the minds of suicidal subjects. The aim of the study was to investigate the relationship of intent and lethality in medically serious and medically non-serious suicide attempts and to examine relationship of specific psychological and clinical variables with the subjective and objective components of suicide intent. METHODS: The study group included 102 participants, 35 consecutive subjects hospitalized for a medically serious suicide attempt and 67 subjects who presented to the same tertiary medical center after a medically non-serious suicide attempt. All were interviewed with the SCID-I and completed the Suicide Intent Scale (SIS), the Lethality Rating Scale, and instruments measuring mental pain and communication difficulties. RESULTS: Patients who made medically serious suicide attempts had higher total SIS score and higher objective and subjective subscale scores. The objective component of the SIS was highly correlated with the lethality of the suicide attempt and communication difficulties; the subjective component was associated with mental pain variables. The interaction of mental pain and communication difficulties was predictive of the severity of the objective suicide intent. LIMITATIONS: Relatively small number of patients with medically serious suicide attempt and the relatively large number of questionnaires which may to some extent have diminished informant reliability. CONCLUSIONS: Suicidal individuals with depression and hopelessness who cannot signal their pain to others are at high risk of committing a medically serious suicide attempts.

Signal transduction by CD58: the transmembrane isoform transmits signals outside lipid rafts independently of the GPI-anchored isoform.

The adhesion molecule CD58 is natively expressed in both a glycosylphosphatidylinositol (GPI)-anchored form and a transmembrane form. We previously demonstrated that the two isoforms of CD58 are differentially distributed in the cell membrane. The GPI-linked form resides in lipid rafts while the transmembrane form resides outside lipid rafts. Following cross-linking a fraction of transmembrane CD58 redistributes to lipid rafts. It has also been demonstrated that ligand binding to CD58 induces biological functions such as cytokine production and immunoglobulin isotype switching, indicating that cell-cell interactions result in CD58-mediated signal transduction. However, the signaling pathways involved in these activation processes are poorly defined. Here we show for the first time that cross-linking of CD58 induces protein tyrosine phosphorylation of BLNK, Syk and PLCgamma, and activation of ERK and Akt/PKB. In addition, we studied how these signaling events relate to the distinct membrane localization of the two isoforms of CD58. We demonstrate that cross-linking of CD58 triggers signaling that is predominantly associated with transmembrane CD58 in nonraft microdomains. Moreover, signaling through transmembrane CD58 does not depend on coexpression of the GPI-linked isoform. Thus, despite the residence of its GPI-anchored isoform in lipid rafts and the translocation of a fraction of its transmembrane isoform to lipid rafts, CD58 signaling is triggered by the transmembrane isoform outside lipid rafts. These findings corroborate signaling outside lipid rafts, as opposed to the established notion that rafts function as essential platforms for signaling.

Mental pain and its communication in medically serious suicide attempts: an "impossible situation".

BACKGROUND: The study of near-fatal suicide attempters may provide insight into the minds of suicidal subjects. Our aim is to test the hypothesis that mental pain is a general risk factor for suicidal behavior and communication difficulties are a particular risk factor for medically serious suicidal behavior. METHODS: Thirty five subjects who made medically serious suicide attempts were compared with 67 medically not serious suicide attempters and 71 healthy controls. All were interviewed with the SCID-I and completed questionnaires covering mental pain, communication difficulties and seriousness of suicide attempt. RESULT: Variables from the mental pain domain (e.g. depression) predicted the presence of suicidal behavior, and variables from the communication difficulties domain (e.g., self-disclosure) predicted the lethality and seriousness of the suicide attempts. LIMITATIONS: Relatively small number of patients with medically serious suicide attempt and the relatively large number of questionnaires which may to some extent have diminished informant reliability. CONCLUSIONS: Problems with sharing of feelings with others are an important risk factor for near-lethal suicide, over and above the contribution of psychiatric illness and mental pain, including depression and hopelessness.