BACKGROUND: Previous studies have identified the association between diabetes mellitus and liver cancer. However, the detail of this association is still unclear, in terms of confounding factors, the trend according to the duration of diabetes, and the interaction between diseases associated with the liver cancer and this association. The purpose of the present study was to examine the association between diabetes and liver cancer in view of the trend and the interaction. METHODS: The baseline survey was conducted during the period 1986-1989 among the general population of Fukuoka Prefecture, Japan (15 417 persons aged 30-79 years). The respondents were assessed for history of diabetes, age at which they had had diabetes, and other covariates by means of a baseline questionnaire. A total of 7308 persons aged 40-79 years were retrieved for the main analysis and 4902 persons for a subcohort from which the information on history of diseases associated with liver cancer were obtained. The relative risks (RRs) and their 95% confidence intervals (CIs) were estimated using the Cox proportional hazards model. RESULTS: After adjustment for smoking, alcohol and the diseases associated with liver cancer, the RR for liver cancer was 2.06 (95% CI=1.01-4.19). Diabetes increased the risk of liver cancer in persons with hepatitis and/or cirrhosis (RR=2.90, 95% CI=1.13-7.41). However, the RR of diabetes for liver cancer was 1.35 (95% CI=0.41-4.43) in persons without hepatitis and cirrhosis. The trend according to the duration of diabetes was not seen. CONCLUSIONS: A significant association between diabetes and liver cancer was observed. Moreover, this association was modified by hepatitis and cirrhosis.

Adult↗

PubMedDate not supplied

The motor end-plate fine structure and ultrastructural localization of acetylcholine receptors in amyotrophic lateral sclerosis.

The motor end-plate fine structure and distribution of junctional acetylcholine receptors (AChRs) in patients with amyotrophic lateral sclerosis (ALS) were studied. Morphometric analysis was carried out in 74 end-plates (92 innervated and 47 denuded postsynaptic regions) from 10 patients with ALS. AChR was studied by means of peroxidase-labeled alpha-bungarotoxin binding in 45 end-plates (86 innervated and 36 denuded postsynaptic regions) from 6 patients with ALS. The postsynaptic regions were denuded of their nerve terminals in 33.8% (9.8% in controls). However, the postsynaptic folds in denuded regions were fairly well preserved, as were junctional AChRs. No highly simplified postsynaptic regions were observed. These results suggest that reinnervation of the skeletal muscle by nerve sprouting in ALS may occur in the previously denuded postsynaptic regions and the preserved postsynaptic regions including AChRs, the basement membrane, and Schwann cells may play an important role in this process.

Adult↗

PubMedDate not supplied

Molecular characterization of the "26S" proteasome complex from rat liver.

The molecular properties of an ATP/ubiquitin-dependent "26S" proteasome complex purified from rat liver were examined by physicochemical, biochemical, and morphological analyses. On ultracentrifugation, the proteasome complex sedimented as almost a single component with a sedimentation coefficient of 30.3S. Dynamic light-scattering measurements indicated that it has a diffusion coefficient of 1.38 x 10(-7) cm2/sec and a Stokes radius of 15.5 nm. From these two coefficients, the protein complex was estimated to have the high molecular weight of 2.02 x 10(6). Static light-scattering analysis indicated a molecular weight of 1.91 x 10(6) and a radius of gyration of 16.8 nm. The proteasome complex was found to be composed of multiple subunits of the 20S proteasome with molecular weights of 2.1-3.1 x 10(4) and 15-20 protein species with molecular weights of 3.5-11.0 x 10(4), which were directly associated with the 20S proteasome. The electron micrographic finding that the 26S proteasome complex had a caterpillar shape, direct electronmicroscopic observations on the subunit arrangement of the 20S proteasome, and classification of the subunits of the latter into two groups with respect to sequence homology suggested that the 26S complex is a symmetrical assembly of two domains, each containing a large terminal subset and half the central 20S subset of components. For clarification of the molecular structure of the 26S proteasome complex in solution, its physicochemical parameters were calculated theoretically using a model based on this caterpillar-shaped complex. The values obtained for the Stokes radius and radius of gyration of 12.2 and 14.9 nm were consistent with the experimental values. These results provide evidence that the 26S proteasome complex is a cylindrical caterpillar-like structure of "30S" in solution, consisting of a 20S proteasome component with proteolytic function and multiple other components, which possibly have regulatory roles.

Adenosine Triphosphate↗