Establishment and partial characterization of a continuous human malignant glioma cell line: NG97

1. A human glioma cell line, NG97, was established from tissue obtained from a patient diagnosed with a grade III astrocytoma. 2. The NG97 cell line has been subcultured for more than 100 passages in standard culture media without feeder layer or collagen coatings. 3. NG97 cells grow in vitro as two subpopulations with distinct morphological appearance: stellate cells with pleomorphic nuclei, and small round cells with few processes. The cells have a doubling time of about 72 h and a plating efficiency of 1%. The injection of NG97 cells into congenitally athymic mice induced the formation of solid tumor masses that could be retransplanted every 4 weeks. The cells obtained from tumor mass when cultivated in vitro had a morphology comparable to those of the initial culture. 4. This cell line may prove useful for cellular and molecular studies as well as in studies of gliomas treatment.

The role of hypotension in the pathogenesis of sudden hearing loss

The generic term 'sudden hearing loss' indicates the lack of knowledge about the etiology and pathogenesis of this phenomenon. In most cases it would seem feasible to consider infections or organic circulatory defects, but there are cases, generally affecting young subjects in whom the damage is often reversible, in which a functional origin is possible. We therefore investigated the possible effect of systemic arterial pressure in a retrospective study in a group of 36 patients aged not more than 40 years, treated for sudden hearing loss, comparing the mean values of their arterial pressure with those of a control group of 25 subjects, of similar age, admitted for other disorders. The significantly lower mean values of arterial pressure in the group affected by sudden hearing loss and the easier reversibility of the damage in these patients suggests that, at least in some cases, the cochlear damage may be caused by a perfusion deficit due to the combined effect of hypotension and imperfect vasomotor regulation.

Cardiovascular disease and Lp(a) in the adult population and in the elderly: the Brisighella study

OBJECTIVE

The aim of this study was to evaluate the distribution of the concentrations of lipoprotein(a) [Lp(a)] in a free-living population, that of Brisighella, and to study the degree of association with cardiovascular disease (CVD) and other associated risk factors. The Brisighella study is included in the framework of observational and interventional longitudinal studies; it began in 1972 to monitor the spontaneous trend of the risk factors for atherosclerosis and to evaluate the incidence of CVD in a rural population.

METHODS

The studies were carried out on 1319 subjects, 627 males and 692 females, aged over 14 years, of which 134 men and 113 women were geriatric (age > 64 years); the data are relative to the control of the population in 1988. The following were evaluated for each subject: (a) weight and height; (b) hematological parameters; (c) clinical events; (d) presence of other concomitant diseases. For the dosage of the hematological parameters, enzymatic-colorimetric parameters were used (total and HDL cholesterol, triglycerides, glycemia and uremia), radial immunodiffusion and immunoturbidimetry (apoAI and B), ELISA-sandwich immunoenzymatic method (Lp(a)). All the methods used are standardized and internal and external laboratory quality control was carried out. The data collected were analyzed with the program STATGRAPHIC VERSION 6.0; the mean, the standard deviation and the median were calculated for all the variables. The frequency tables, distribution curves (approximation estimates with the chi 2 test), and single and multiple regression were also calculated. A value of p < 0.01 was taken as the level of significance.

RESULTS

The distribution of Lp(a) in the control population and in subjects with CVD was substantially the same for both sexes; the differences between the mean levels of Lp(a) were not statistically significant (18.5 mg/dl vs 20.09 mg/dl for men and 19.98 mg/dl vs 22.78 mg/dl for women). The same also applies to the elderly population (18.81 mg/dl vs 23.31 in the men and 21.13 mg/dl vs 21.47 mg/dl in the women). No significant variations were observed in the mean values of Lp(a) even when other risk factors were taken into consideration, such as hypertension, obesity and diabetes. Finally, multiple regression analysis did not show any correlation between Lp(a) levels and those of the other hematological parameters.

CONCLUSIONS

In this transversal study, we found no evidence to suggest that Lp(a) can be considered and independent and predictive risk factor for CVD. It would therefore seem that in the population of Brisighella the levels of Lp(a) are "causally" distributed, without any correlation with the presence of cardiovascular events or with hypertension, diabetes or obesity in both sexes.