Pharmacological characterization of a novel AVP(4-9) binding site in rat hippocampus

pGlu-Asn-Cys (Cys)-Pro-Arg-Gly-NH(2) (AVP(4-9)), a major metabolite C-terminal fragment of Arginine(8)-vasopressin (AVP), improves the disruption of the learning and memory, and is a far more potent in the mnemonic function than AVP. In this study, we pharmacologically characterized its putative binding site and mechanism of intracellular signaling. Radioligand binding assay showed that [35S]AVP(4-9) could detect specific binding sites in the rat hippocampus membrane preparations, and the binding site was specifically displaced by AVP(4-9) but not by either V(1) or V(2) antagonists. Furthermore, [35S]AVP(4-9) could not detect the cloned rat V(1a), V(1b) and V(2) vasopressin receptors. Even at a low doses (10-100 pM), AVP(4-9) caused an increase in both inositol(1,4, 5)-trisphosphate (Ins(1,4,5)P(3)) and intracellular calcium concentrations ([Ca(2+)](i)) in rat hippocampal cells. The AVP(4-9)-induced [Ca(2+)](i) increase was partially inhibited by the absence of Ca(2+) or by Ca(2+)-channel blocker, suggesting that AVP(4-9) caused the [Ca(2+)](i) increase via release from intracellular calcium store as well as influx from extracellular calcium. For the first time, this study provides evidence to show that AVP(4-9) activates Ins(1,4,5)P(3)/[Ca(2+)](i) pathway through a novel type of receptor in rat hippocampus, which might be potentially important in improving the mnemonic function.     

Role of caspase-1 subfamily in cytotoxic cytokine-induced oligodendrocyte cell death

Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS.     

The low prevalence of high levels of expressed emotion in Bali

The present study contrasts the expressed emotion (EE) status in family members of schizophrenic patients between Bali (Indonesia) and Tokyo (Japan), the former being a non-industrialized society and the latter an industrialized society in Asia. The EE ratings of each key relative for 62 consecutively hospitalized schizophrenic patients at the Bangli State Mental Hospital (Bali) and 33 consecutively admitted schizophrenics at Komagino Hospital (Tokyo) were obtained using the Five Minute Speech Sample (FMSS) method. A significantly lower prevalence of high EE (12.9%) was observed in Bali compared with Tokyo (36.4%) (P<0.01). This result may explain the better social adjustment of schizophrenics in Bali. In addition, in Bali, to clarify the EE effect in this non-industrialized society, we examined the relationship between each key relative's EE and the patient's psychotic symptoms at admission, as assessed by the Brief Psychiatric Rating Scale (BPRS) and the Scales for the Assessment of Negative Symptoms (SANS). Moreover, the association between each family member's EE and a patient's rate of re-admission over the 1-year period following discharge was evaluated. The EE value was significantly related to the anxious-depression factor score in the BPRS, but not to either of the other factor scores in the BPRS or SANS subscales. Furthermore, EE status was not a reliable predictor of patient re-admission over the 1-year period following discharge in Bali.     

High Expression of SQSTM1/p62 Protein Is Associated with Poor Prognosis in Epithelial Ovarian Cancer

High expression of SQSTM1/p62 (p62) protein, which functions as a hub for various cellular signaling pathways, has been detected in several human cancers. However, the clinicopathological impact of high p62 expression is largely unknown in epithelial ovarian cancer (EOC). Here, the expression level of p62 in primary EOCs (n=266) was assessed by immunohistochemistry, and its clinical significance was analyzed. Univariate and multivariate analyses were used to determine the impact of p62 expression on overall survival. p62 was expressed in the cytoplasm (Cyto) and/or nucleus (Nuc) in primary EOCs, and an expression subtype (Cyto^High/Nuc^Low), showing high expression in the cytoplasm but low expression in the nucleus, was significantly correlated with serous carcinoma (P<0.001), advanced stage (P=0.005), presence of residual tumor (P<0.001), and low overall survival rate (P=0.013). Furthermore, in serous carcinomas (n=107), the p62 Cyto^High/Nuc^Low subtype was significantly correlated with low overall survival rate (P=0.019) as an independent factor (P=0.044). Thus, our findings suggest that high expression of cytoplasmic p62 may be a novel prognostic biomarker in EOC, particularly in serous carcinoma.     

Laparoscopic grasper for intramedullary biopsy: a technique to improve tissue sampling

Reaming samples are usually sent for histological testing to establish or confirm the primary source of malignancy while intramedullary nailing is performed for impending or established pathological fracture of the long bones. However, this conventional technique of sampling does not always yield accurate results. Herein, we introduce a technique for intramedullary biopsy using a laparoscopic grasper under image intensifier guidance. This novel technique was applied in three cases, and the tissue samples obtained successfully established or confirmed the primary source of malignancy. In comparison, reaming samples obtained via the conventional method showed negative findings in one case and tumour cells that were of poor sample quality in another case. We opine that this new technique is an effective and reproducible method that could improve tissue sampling and achieve a more reliable histological diagnosis.