Pertechnetate release from a water/oil microemulsion and an aqueous solution after subcutaneous injection in rabbits.

A water-oil microemulsion and an aqueous solution, both carrying pertechnetate, were injected subcutaneously in rabbits; release was observed by imaging the administration sites with a gamma-camera. Disappearance from the injection site of pertechnetate in aqueous solution was about ten times faster than that of pertechnetate in a microemulsion.

Cerebral blood flow and volume in symptom-free migraineurs: a SPECT study.

Both CBF and CBV were evaluated by gamma-camera SPECT in 14 patients with classic migraine, all studied while symptom-free. Nuclear data were correlated with CT and MRI. A decreased regional CBF was observed in 13 of the 14 patients. The decreased perfusion was localized in the frontal lobe in 6 patients, the temporal lobe in one, the parietal lobe in 11 and the occipital lobe in 5 patients. The parieto-occipital cortex was involved more often than the frontal cortex; the association of hypoperfusion with parieto-occipital cortex was quite high. The right parieto-occipital regions were affected more often than the left ones. Regional CBV was increased in 8 patients. There was good topographical concordance between decreased CBF and increased CBV, but the increase of CBV was in general more evident at the periphery of the hypoperfusion. It is of interest that the only patient with a normal CBF study had a pathological CBV study. Apparently, CBF derangements are very common in symptom-free patients with classic migraine, a CBF decrease being often accompanied by a CBV increase. In these patients both CT and MRI have a lower diagnostic yield than SPECT.

[Insulin receptors in the HL60 human promyelocytic leukemic cells line]. / Recettori insulinici nelle cellule della linea promielocitaria umana HL60.

The insulin binding characteristics of human promyelocitic HL60 cell line was studied by the use pf I(125) insulin. The binding activity was found to increase linearily both with the number of cells and with the incubation time. The competition curve with increasing concentration of unlabeled insulin demonstrated of specific receptors. The number of receptors was estimated to be 6.36 . 10(6) per cell.

[Decrease of insulin binding to human acute leukemic cells during chemically induced differentiation]. / Modificazioni dell'attivita' legante l'insulina di cellule leucemiche umane durante la differenziazione indotta da sostanze chimiche.

The specific insulin binding activity of human promyelocitic HL 60 cell line during the myeloid and macrophagic differentiation induced by chemical compounds was investigated. Dimethyl sulfoxide (DMSO) and retinoic acid myeloid induced differentiation in HHL 60 cells was accompanied by a marked decrease of insulin receptors. In K 562 cell line, where DMS O has no effect on differentiation, the number of insulin receptors was only slightly affected. 12-0-tetradodecanoil phorbol 13-acetate (TPA) induced macrophagic differentiation of HL 60 cell line was also accompanied by a decrease of insulin binding activity. Our results support the hypothesis that during the process of terminal differentiation a decrease of insulin receptors occurs.

Proinsulin and A-component antibodies in diabetics after long-term monocomponent insulin treatment.

In newly diagnosed diabetics treated with Monotard (porcine monocomponent (MC) Lente insulin) for five years, no antibodies against porcine or bovine proinsulin were observed, but 2 of 13 subjects developed a-component antibodies. In newly diagnosed diabetics, treatment for the same period with conventional Lente insulin induced both proinsulin and a-component antibodies (in 5 and 8 of 10 cases, respectively). In 31 patients transferred from conventional Lente to Monotard, proinsulin and a-component antibody levels were significantly lower than in 22 patients maintained on conventional Lente after the 5-year follow-up period. No significant differences were noted between bovine and procine proinsulin antibodies. Insulin antibody production was similar to that of proinsulin antibody.

[Clinical experiences with monocomponent insulins]. / Esperienze cliniche con le insuline monocomponenti

The immunogenicity of conventional therapeutical insulin is discussed according to the concepts of Schlichtkrull: the formation of insulin antibodies is not attributable to the pure Sanger's insulin molecule, but to related protein impurities, present in all crystallized pig and ox insulin preparations. The terms of monocomponent insulin, highly purified insulin, and single peak insulin in defined and personal clinical results obtained with Novo Monocomponent Lente Insulin over a period of 3 years are presented. The Hein Christiansen's radioimmunoelectrophoretic method fo estimation of 125I-insulin IgG binding was used to determine insulin antibody levels. It was found that: 1) Newly detected insulin-dependent diabetics, never previously treated with insulin, do not produce insulin antibodies at a significant level; 2) Long-term insulin treated diabetics, transferred to monocomponent treatment, tend to reduce their antibody levels, if initially high, altough with transient recurrent peaks; 3) Stimulation of the immunocompetent system by intercurrent infection does not generally modify the immunological situation. Apart from immunological changes, satisfactory clinical results were observed in cases of high insulin requirement, insulin allergy, insulin lipoatrophy. Present practical indications for monocomponent insulin therapy (Actrapid-Lenta) are proposed.

[Evaluation of the antibody anti-insulin titer using Christiansen's radioimmunoelectrophoresis in clinical diabetology]. / Valutazione del titolo anticorpale anti-insulina colla tecnica radioimmunoelettroforetica di Christiansen in diabetologia clinica.

On the basis of personal experience concerning 2020 consecutive determinations, the radioimmunoelectrophoretic method of Christiansen for 125I-Insulin-Binding to IgG (= IB, significant limits = mU/ml) has been proved as a reliable tool for the evaluation of insulin antibody titer in clinical diabetology. After a critical review of the recent literature about insulin antibodies both without and after exogenous immunization, the following results are presented and discussed. 1) - In 163 diabetic subjects, never previously treated with insulin, the mean value of IB was X = 0,008 mUml (sigma = 0,023 . Sx = 0,002). 2) - In 221 longterm insulin-treated diabetics the mean value of IB was X = 1,50 mU/ml (sigma = 2,15 . Sx = 0,145). 3) -In 46 insulin-dependent diabetics, serial determinations of IB allowed to follow the insulin antibody production during a 5 years treatment with monocomponent insulin )Lente MC). No or slight antibody formation was observed in newly diagnosed patients, never previously treated with insulin. High antibody starting levels showed tendency to a gradual reduction, after switching from conventional insulin treatment to the monocomponent one. These modifications in the IB values have been studied in correlation with the clinical course of conditions possibly referred to an immunologic pathogenesis, such as: brittle diabetes, high insulin requirement, insulin allergy, insulin lipoatrophy, diabetic microangiopathy. No significant variations in IB values were observed after viral infections.