Brain lipids of a case of juvenile Niemann-Pick disease

—Lipids of frontal lobe grey and white matter were examined in parallel from a normal and a diseased child (M. Niemann-Pick), both nine years of age. In the grey matter of the pathological case the following changes, although small, were found: a slight increase in all phospholipids and decreased values for nervonic acid in cerebrosides and for hydroxy fatty acids in sulphatides. White matter seemed much more affected by the disease: water content was about 6 per cent higher which corresponds to an approx. 20 per cent loss of dry substance compared with the normal brain. Further increases were observed in ‘ganglioside’ fraction and in all phosphatides. Cerebroside and sulphatide levels appeared decreased owing to destruction of myelin. In all of the glycerophosphatides oleic acid portions were lowered whereas in sphingolipids mainly nervonic acid values were reduced. Aldehyde content of both tissues seemed lowered in the disease, however, changes in composition were observed only in white matter, where the stearaldehyde portion of ethanolamine glycerophospholipid increased at the expense of palmitaldehyde and oleinaldehyde.     

A simple vertebrate collagenase assay using soluble radioactive collagen substrate

A highly sensitive assay for vertebrate collagenase has been developed using [14C]proline- or [3H]proline-labeled collagen as soluble substrate. The substrate was easy to prepare, gave high specific activity (1.4 X 10(6) cpm/mg collagen), and was stable at -20 degrees C for a long period. The digestion reaction for the assay was done at 21 degrees C to minimize the cleavage of collagen by proteases other than collagenase and to protect the 3/4 and 1/4 cleavage fragments of collagen from being further attacked by proteases. The cleaved products were denatured and then separated from undigested native collagen by precipitation with 1 M NaCl at pH 3.5. The conditions selected for denaturation and separation gave better discrimination between the cleaved products and uncleaved substrate than did conditions used in some other assays. The digestion products can be examined further by gel electrophoresis at the end of the assay to confirm the activity of vertebrate collagenase. This assay can also be adapted to assess telopeptidase activity independently of collagenase activity.     

Quantitative patterns of Hsps in tubular adenoma compared with normal and tumor tissues reveal the value of Hsp10 and Hsp60 in early diagnosis of large bowel cancer

Large bowel carcinogenesis involves accumulation of genetic alterations leading to transformation of normal mucosa into dysplasia and, lastly, adenocarcinoma. It is pertinent to elucidate the molecular changes occurring in the pre-neoplastic lesions to facilitate early diagnosis and treatment. Heat shock proteins (Hsps), many of which are molecular chaperones, are implicated in carcinogenesis, and their variations with tumor progression encourage their study as biomarkers. There are many reports on Hsps and cancer but none to our knowledge on their systematic quantification in pre-neoplastic lesions of the large bowel. We performed immunohistochemical determinations of Hsp10, Hsp60, Hsp70, and Hsp90 in biopsies of large bowel tubular adenomas with moderate grade of dysplasia and compared to normal mucosa and adenocarcinoma with a moderate grade of differentiation (G2). A significant elevation of Hsp10 and Hsp60 only, i.e., in the absence of elevation of Hsp70 or Hsp90, in both epithelium and lamina propria was found in tubular adenoma by comparison with normal mucosa. In contrast, adenocarcinoma was characterized by the highest levels of Hsp10 and Hsp60 in epithelium and lamina propria, accompanied by the highest levels of Hsp70 only in epithelium and of Hsp90 only in lamina propria, by comparison with normal and tubular adenoma counterparts. Hsp10 and Hsp60 are promising biomarkers for early diagnosis of tubular adenoma and for its differentiation from more advanced malignant lesions. Hsp10 and Hsp60 may be implicated in carcinogenesis from its very early steps and, thus, are potentially convenient targets for therapy.