The protective effect of MT-α-glucan against streptozotocin (STZ)-induced NIT-1 pancreatic ß-cell damage.

The protective effect of an alpha-glucan (designated here as MT-α-glucan) from fruit body of maitake (Grifola frondosa) on NIT-1 pancreatic ß-cells damaged by streptozotocin (STZ) in vitro was investigated. The cell viability, insulin secretion, the activity of superoxide dismutase (SOD), glutathione peroxidase (GSHpx) and the content of reduced glutathione (GSH) increased significantly when the cells were incubated with MT-α-glucan (400, 200 µg ml(-1)). The content of malondialdehyde (MDA), nitric oxide (NO) production, and the activity of NO synthase (NOS), inducible NOS (iNOS) decreased significantly when the cells were incubated with MT-α-glucan. The destructive changes of NIT-1 cells ameliorated when incubated with MT-α-glucan under microscopic observation. These data suggested that MT-α-glucan had obvious protective effect on NIT-1 pancreatic ß-cells damaged by STZ, which might be related to its effects of decreasing levels of ß-cell-destroying factors such as oxidative stress and NO synthesis.

INVESTIGATION OF A HUGE FAMILY WITH AUTOSOMAL DOMINANT HEREDITARY NON-SYNDROMIC HEARING LOSS / 解放军医学杂志

To investigate a huge family with autosomal dominant hereditary non syndromic hearing loss. In this family, sixty six of 113 family members and 8 spouses have been conducted physical examination, pure tone audiometry, immittance testing and auditory brainstem response testing (ABR). The results indicated that 37 of 66 tested family members have sensorineural hearing loss in various degrees. No associated visible abnormalities in other systems were found in this family. The mode of inheritance of this family should be autosomal dominant according to its pedigree. The full collections of both blood samples and physiological hearing assessments of this family have provided the solid basis for future study on identifying disease causing gene.