Increase in the advanced glycation end product pentosidine in Bruch's membrane with age

PURPOSE: To determine whether there is an age-related increase of pentosidine in human Bruch's membranes and to localize pentosidine and carboxymethyllysine (CML), two well-characterized, advanced glycation end products (AGEs) in aged human Bruch's membranes and choroid in vivo. METHODS: Human Bruch's membrane samples were isolated from the retinal pigment epithelium (RPE) and choroid and subjected to reversed-phase high-performance liquid chromatography to determine pentosidine content. A polyclonal anti-pentosidine antibody and a monoclonal antibody specific for carboxymethyllysine were used to localize AGEs in 20-month-old nondiabetic, 82-year-old nondiabetic, and 82-year-old diabetic globes. RESULTS: Human Bruch's membranes (n = 20) showed a linear age-dependent increase in pentosidine that reached approximately 0.17 millimoles pentosidine per mole hydroxyproline in late life (r = 0.896; P < 0.001). Immunohistochemical evaluation showed evidence of pentosidine in Bruch's membrane, choroidal extracellular matrix, and vessel walls in the 82-year-old nondiabetic and diabetic globes. A similar staining pattern was found with the anti-CML antibody. Basal laminar deposits and drusen stained with both antibodies in the elderly nondiabetic eye. In contrast, neither antibody stained the 20-month-old tissue. CONCLUSIONS: We provide biochemical and immunohistochemical evidence for the formation of pentosidine and CML structures in human Bruch's membrane and choroid with age. These changes could promote aging of the RPE-Bruch's membrane-choroid complex.     

Nocturnal sleep spindle activity in blind subjects

To determine spindle activity during sleep in congenitally blind subjects, electroencephalogram sleep recordings were done on two or three consecutive nights in five subjects aged in their 20s and 30s. The number per minute and the duration of sleep spindles, scored visually, were compared with the data of sighted persons of comparable ages. The results indicated that the total number of sleep spindles a night was ranged from 117 to 585, and the number per minute ranged 0.52 to 2.06 during stage 2. Both values were much less than the values of sighted persons.     

The effect of interleukin-6 on enhancing the invasiveness of head and neck cancer cells in vitro

Patients with head and neck cancers that produce a high concentration of granulocyte colony-stimulating factor (G-CSF) or patients with esophageal squamous cell carcinomas who have elevated serum interleukin-6 (IL-6) concentrations have been found previously to be at significant risk for tumor invasion to adjacent organs as well as frequent metastases. This suggests that G-CSF and Il-6 enhance the invasiveness and metastatic potential of cancer cells. We studied the in vitro invasiveness of head and neck cancer cell lines with and without recombinant human G-CSF (rhG-CSF) and human IL-6 (hIL-6) in an extracellular matrix membrane system. The degree of invasiveness was affected by incubating cells with hIL-6, but not by pre-incubating the cell-matrix with hIL-6. The maximum concentration of hIL-6 for enhanced invasiveness was approximately 5,000 u/ml. In addition, rhG-CSF enhanced the invasiveness of tumor cells that produced large amounts of G-CSF. The present study also suggests that tumor cells tend to invade and metastasize in an environment rich in hIL-6. Received: 3 November 1997 / Accepted: 1 April 1998     

Characterization of mouse Ire1 alpha: cloning, mRNA localization in the brain and functional analysis in a neural cell line

In yeast, an endoplasmic reticulum (ER)-associated protein, Ire1p, is believed to initiate the unfolded protein response (UPR), that is responsible for protein folding in the ER under stressed conditions. Two mammalian homologs of Ire1p have been identified, Ire1 alpha and Ire1 beta. We have previously reported that familial Alzheimer's disease linked presenilin-1 variants downregulate the signaling pathway of the UPR by affecting the phosphorylation of Ire1 alpha. In the present study, we cloned the mouse homolog of Ire1 alpha for generating genetically modified mice. Ire1 alpha was ubiquitously expressed in all mouse tissues examined, and was expressed preferentially in neuronal cells in mouse brain. This led us to investigate the effects of the downregulation of the UPR on the survival of neuronal cells under conditions of ER stress. Morphological and biochemical studies using a dominant-negative form of mouse Ire1 alpha have revealed that cell death caused by ER stress can be attributed to apoptosis, and that the downregulation of the UPR enhances the apoptotic process in the mouse neuroblastoma cell line, Neuro2a. Our results indicate that genetically modified mice such as transgenic mice with a dominant-negative form of Ire1 alpha might provide further understanding of the pathogenic mechanisms of Alzheimer's disease and other neurodegenerative disorders.     

Multi-impulsivity among bulimic patients in Japan

OBJECTIVE: Studies in Western world patients suggest the possible existence of a subgroup of patients with bulimia nervosa (BN) who display multiple problems with impulsivity, such as suicidal attempts. We assessed impulsive behaviors among BN patients in Japan to discuss them crossculturally. METHOD: Impulsive behaviors in 64 BN patients were assessed and multi-impulsivity (MI) was defined according to the definition proposed by Fichter, Quadflieg, and Rief (Psychological Medicine, 24, 591-604,1994). RESULTS: Nineteen patients (30%) met the definition of MI. BN patients with MI had more severe clinical features, such as concurrent depressive and anxious symptoms, global functioning, and higher prevalence of borderline personality disorder than BN patients without MI. DISCUSSION: These results showed the similarities between BN patients with MI in Japan and those patients in the Western world in clinical and psychopathological characteristics and a life-time incidence of each impulsive behavior. These findings may suggest culturally free bases for linkage between BN and MI.     

C1 inhibitor for prophylaxis of xenograft rejection after pig to cynomolgus monkey kidney transplantation

BACKGROUND: Early rejection of discordant porcine xenografts in primate recipients is initiated by the intragraft binding of either preformed (hyperacute xenograft rejection) or induced (acute vascular rejection) antiporcine recipient antibodies with subsequent complement activation via the classical pathway. We have investigated the efficacy of the supplemental administration of C1-inhibitor (C1-INH), a specific inhibitor of the classical complement activation pathway, for prophylaxis of xenograft rejection in a pig to primate kidney xenotransplantation setting. METHODS: Based on the results of pharmacokinetic studies performed in two nontransplanted monkeys, supplemental C1-INH therapy was administered daily to three Cynomolgus monkeys receiving a life-supporting porcine kidney transplant together with cyclophosphamide-induction/cyclosporine A/mycophenolat-mofetil/steroid immunosuppressive therapy. RESULTS: In the three monkeys receiving porcine kidney xenografts and continuous C1-INH treatment none of the grafts underwent hyperacute rejection; all xenografts showed initial function. Recipient survival was 13, 15, and 5 days. No graft was lost due to acute vascular rejection. All animals died with a functioning graft (latest creatinine 96, 112, and 96 micromol/liter) due to bacterial septicemia. CONCLUSION: We conclude that, in our model, supplemental C1-INH therapy together with a standard immunosuppressive regimen can be helpful for prevention of xenograft rejection in a pig to primate kidney xenotransplantation setting. The optimal dose and duration of C1-INH treatment, however, has yet to be determined.     

Prediction of the response to chemoradiation and prognosis in oesophageal squamous cancer

BACKGROUND: The sensitivity of cancer cells to chemotherapy and radiation therapy depends on various biological properties. This study investigated the expression of p53, CDC25B and metallothionein (MT), and evaluated their clinical significance in chemoradiation therapy (CRT) for oesophageal squamous cell carcinoma.METHODS: The expression of p53, CDC25B and MT was evaluated by immunohistochemistry using biopsy specimens taken before CRT for 77 patients with oesophageal squamous cell carcinoma, and correlated with the pathological effects of CRT and survival.RESULTS: p53-positive tumours and MT-positive tumours had a poor response to CRT, whereas tumours with strong CDC25B expression were associated with a good response. When each patient was scored for the presence of the three biological factors, there was a strong correlation between the sensitivity score and the pathological effect of CRT (P < 0.001), and a (non-significant) difference in the 5-year survival rate between patients with a high score and those with a low score (67 versus 34 per cent respectively; P = 0.12).CONCLUSION: The combined evaluation of p53, CDC25B and MT may help to identify patients with advanced oesophageal squamous cell carcinoma who will benefit from preoperative CRT.