Culture and differentiation of chondrocytes entrapped in alginate gels

Summary We studied the response to culture conditions and the differentiative ability in suspension culture in alginate gels of resting chondrocytes from the preosseous cartilage of adult pig scapula. It was found that the maximum rate of chondrocyte duplication is reached at the fourth day in culture whereas the rate of proteoglycan synthesis and alkaline phosphatase expression do not gain a maximum value before the seventh day. During the culture time, the chondrocytes undergo differentiation as it is demonstrated by the alkaline phosphatase specific activity increase and by morphological criteria (hypertrophy, increase of the number of mitochondria per cell, increased endoplasmic reticulum, matrix vesicle production). The alginate gels can be easily dissolved to obtain cell populations in which the variation of cytosolic calcium concentration following a proliferative stimulus can be conveniently observed using the conventional procedure of Fura 2.     

Comparative effects of heating and fasting in mice, with particular reference to development of Sarcoma 180

Effects of heating and fasting, both alone and associated, have been studied in normal and Sarcoma 180 bearing mice. Heating reduced body weight and tumour mass and increased body temperature. Fasting reduced body weight, while tumour mass and body temperature were slightly affected. By associating heating and fasting a more marked decrease of body weight was produced than by each of the two factors involved, while effects on body temperature and on tumour mass were unchanged with respect to heating alone. 6-mercaptopurine was similar to heating in reducing body weight and tumour mass.     

Percutaneous gastrostomy for enteral feeding

Over a period of 18 months, percutaneous nonendoscopic gastrostomy using the Seldinger technique was successfully performed in 32 adults for enteral feeding. There were no deaths or major morbidity related to the procedure. Three patients died of existing disease within 30 days; one had peritoneal irritation following dislodgement of the catheter two days after the procedure but responded to conservative treatment with antibiotics alone. The authors conclude that this procedure is simple and safe and represents the preferred method of gastrostomy for enteral feeding.     

Abnormal glycosylation of hemopexin in arthritic rats can be blocked by bindarit.

Induction of arthritis in rats with Freund's complete adjuvant was accompanied by a distinctive alteration of concanavalin A (Con-A) reactivity in their serum proteins in which the concentrations of selected Con-A reactive proteins were significantly higher when compared to healthy rats. To assess if the observed increase in Con-A reactivity of specific serum proteins reflects an increase in carbohydrate moieties in these proteins in addition to an increase in their protein concentrations, a heme binding serum glycoprotein, hemopexin, also an acute phase reactant, was selected as a marker protein. Hemopexin was purified to apparent homogeneity from pools of serum samples derived from rats with yeast induced inflammation, a monospecific polyclonal antibody was prepared and was used for immunoblot analysis. It was noted that the concentration of hemopexin increased in rats with adjuvant induced arthritis; however, its concentration fell to normal levels after administration with a newly synthesized drug, bindarit, (2-[(1-benzyl-indazol-3-yl)methoxy]-2-methyl propionic acid, C19H20N2O3. Hemopexin was micropurified individually from healthy rats, adjuvant induced arthritic rats, and adjuvant arthritic rats treated with bindarit, cleaved with a Glu-C endopeptidase, Staphylococcus aureus protease V8, and the resultant peptide fragments resolved by SDS-PAGE and examined by silver staining, Coomassie blue staining, and lectin blots using Con-A. It was subsequently noted that hemopexin isolated from adjuvant induced arthritic rats showed a significant increase in Con-A reactivity in selected peptide fragments and that such an increase in glycosylation could be reversed to a pattern similar to healthy rats following treatment with bindarit.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparative analysis of [3H]-thymidine labelling index and monoclonal antibody Ki-67 in non-Hodgkin's lymphomas

The relation between the [³H]-thymidine labelling index (3H-Thy LI), which evaluates the S-phase cells, and the monoclonal antibody Ki-67 (MoAb Ki-67), which recognizes a nuclear antigen expressed during the cell cycle, was defined in 35 non-Hodgkin's lymphomas (NHL). Significantly higher median values of [³H]-Thy LI and Ki-67-positive cells were observed for high-grade than for low-grade malignancy tumours according to the Kiel classification, but with wide and overlapping values for the two morphologic subgroups. A significant correlation was observed between [³H]-Thy LI and Ki-67-positive cells (P < 0.0001; r = 0.62). However, the ratio between the two cell kinetic variables on individual tumours was not constant. It sharply increased with decreasing [³H]-Thy LI values and was much higher in low-grade NHL than in high-grade NHL. Follow-up studies are needed to establish the role of the tumour growth fraction as evaluated by MoAb Ki-67 as a prognostic indicator in NHL.