The translationally controlled tumor protein (TCTP) is a growth-related protein which is regulated at the translational level. It is present in mammals, higher plants and Saccharomyces cerevisiae. This study was undertaken to localize and further characterize the TCTP in human cell lysates using two-dimensional gel electrophoresis, monoclonal antibodies, and 45Ca-gel overlay. TCTP was found in several healthy and tumoral cells including erythrocytes, hepatocytes, macrophages, platelets, keratinocytes, erythroleukemia cells, gliomas, melanomas, hepatoblastomas, and lymphomas. It could not be detected in kidney and renal cell carcinoma (RCC). A monoclonal antibody raised against TCTP detected three isoforms likely due to post-translational modifications. A calcium binding property was found as well as heat stability and cytoplasmic localization. The high degree of homology from plants to man and its expression in many tissues suggests that TCTP most likely has a cell housekeeping function.

The reference plasma protein map, obtained with immobilized pH gradients in the first dimension of two-dimensional electrophoresis, is presented. By microsequencing, more than 40 polypeptide chains were identified. The new polypeptides and previously known proteins are listed in a table and labeled on the protein map, thus providing an update of the human plasma two-dimensional gel database.

Stress, anxiety, and depression (SAD) have a negative impact on the learning and academic performance of university students. Hence, this study aimed to determine the prevalence, as well as the risk factors associated with SAD among a cohort of students pursuing undergraduate degree courses in health sciences. This is part of the strategy in building a healthy nation. A questionnaire containing socio-demographic factors and the short version of Depression, Anxiety, and Stress Scale-21 (DASS-21) was used to assess the likelihood of psychological distress. Logistic regression analysis was conducted to determine the risk factors of SAD. In total, 449 students completed the questionnaire (93.9% response rate). Of these, 65% had stress, 85.1% had anxiety and 51.4% had depression. Most cases of stress (74.6%) and depression (66.2%) were of normal-to-mild level, while 74.6% of them showed moderate-to-extremely severe anxiety. There was a statistically significant association between stress score and the year of study. In the regression analysis, poor sleep quality and fatigue were risk factors of anxiety and depression, whereas low-grade fever and frequent headaches were risk factors for stress and anxiety. Stress, anxiety, and depression scores were significantly higher among students studying medical imaging. A substantial proportion of health science students are suffering from SAD. This study recommends screening and close monitoring of the above-mentioned predictors and the formulation of comprehensive intervention strategies for students with SAD.

SummaryNADPH:protochlorophyllide oxidoreductase (POR) A is a key enzyme of chlorophyll biosynthesis in angiosperms. It is nucleus-encoded, synthesized as a larger precursor in the cytosol and imported into the plastids in a substrate-dependent manner. Plastid envelope membrane proteins, called protochlorophyllidedependent translocon proteins, Ptcs, have been identified that interact with pPORA during import. Among them are a 16-kDa ortholog of the previously characterized outer envelope protein Oep16 (named Ptc16) and a 33-kDa protein (Ptc33) related to the GTP-binding proteins Toc33 and Toc34 of Arabidopsis. In the present work, we studied the interactions and roles of Ptc16 and Ptc33 during pPORA import. Radiolabeled Ptc16/ Oep16 was synthesized from a corresponding cDNA and imported into isolated Arabidopsis plastids. Crosslinking experiments revealed that import of 35 S-Oep16/Ptc16 is stimulated by GTP. 35 S-Oep16/Ptc16 forms larger complexes with Toc33 but not Toc34. Plastids of the ppi1 mutant of Arabidopsis lacking Toc33, were unable to import pPORA in darkness but imported the small subunit precursor of ribulose-1, 5-bisphosphate carboxylase/oxygenase (pSSU), precursor ferredoxin (pFd) as well as pPORB which is a close relative of pPORA. In white light, partial suppressions of pSSU, pFd and pPORB import were observed. Our results unveil a hitherto unrecognized role of Toc33 in pPORA import and suggest photooxidative membrane damage, induced by excess Pchlide accumulating in ppi1 chloroplasts because of the lack of pPORA import, to be the cause of the general drop of protein import.