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Biomedical subjects

G Serafini

Publications and source records attributed to G Serafini.

98 records · Page 6Linked to original sources
PubMedDate not supplied

Role of hexokinase in the regulation of glucose metabolism in human erythrocytes.

Red blood cell glucose metabolism was studied in erythrocytes from a patient with trisomy 10 p which resulted in + 50% hexokinase specific activity, in normal controls and in cases of heterozygous hexokinase deficiency. The results obtained show that the hexokinase activity level is an important factor in the control of the erythrocyte's glycolytic rate while having no appreciable effect on the hexose monophosphate pathway under resting conditions. No clear conclusion could be drawn when an oxidative stress was present.

Blood Glucose↗
PubMedDate not supplied

Purification and properties of the cytoplasmic hexokinase from rabbit brain.

About 90% of the total hexokinase activity in rabbit brain was found to be associated with mitochondria while the remaining part was found in the cytosolic fraction. The soluble enzyme was purified 4,700-fold to near homogeneity by a combination of ion-exchange chromatography, dye-ligand chromatography and affinity chromatography. The purified enzyme showed a specific activity of 110 units/mg of protein and was obtained in 70% yield. The molecular weight of the purified hexokinase was found to be approximately 98,000 both for the native and the denatured enzyme. The isoelectric point, pI, was 6.2 pH units by isoelectric focusing and the enzyme was found to be able to phosphorylate several hexoses. Mg . ATP2-, among the nucleotide substrates, was the most effective phosphate donor. The properties of the purified cytoplasmatic hexokinase were compared with those of the solubilized mitochondrial enzyme. No significant differences were found in molecular weight, isoelectric point, pH dependence of activity, electrophoretic mobility and affinity for glucose and Mg.ATP2-. However, the temperature dependence of activity, and the specificity for several hexose substrates were markedly different.

Animals↗
PubMedDate not supplied

[Campylobacter fetus subsp. jejuni: etiological, epidemiological and preventive aspects].

The Authors, after a brief introduction, examine on the basis of the most recent literature, the taxonomy and the microbiological features of Campylobacter fetus subsp. jejuni, giving a detailed description of the chemical composition, of the biochemical, physiological and nutritional characters, of the antigenic composition and of the cultural methods. Later on, they state the problems arising from the epidemiology of the infections caused by this germ either in man or in animals, examining the most relevant sources of infection. Finally, the Authors describe the most recent laboratory diagnostic methods, the pathogenesis, the clinical manifestations and the prevention of infection, concluding with some therapeutical remarks.

Animals↗
PubMedDate not supplied

Effects of buffers and pH on rabbit red blood cell hexokinase.

The kinetic properties of rabbit red blood cell hexokinase in different buffer systems have been studied. At pH 8.0 the reaction velocity (v) is about 30% higher in glycylglycine compared to Tris, Tea, Hepes or ammonium acetate buffers. The enzyme stability, heat-dependence and spectral properties of the enzyme are also affected by the buffer utilized. None of the following kinetic properties of red blood cell hexokinase varies with pH in the range 6.8-8.5: Km of glucose; Km of ATP and Ki of glucose 6-phosphate.

Acetates↗
PubMedDate not supplied

[Retrospective analysis of color Doppler ultrasonography and flowmetry findings in solid nodular pathology of the breast].

The authors tried to identify useful flowmetric values and color-Doppler patterns for the differential diagnosis between benign and malignant solid breast lesions. To this purpose, 106 patients with breast nodules detected at mammography and/or high resolution US were examined. A US scanner with a linear 7.5 MHz transducer, a narrow sample volume, a PRF ranging (650-800 Hz) and a wall filter value of 50 Hz were used. Three parameters were considered: the number vascular sites, systolic peak velocity and pulsatility index. All these parameters related to tumor volume. Several (> 2) vascular sites, high peak velocity and quite high pulsatility index were demonstrated in malignant tumors (46 lesions). Among benign tumors no vascular site was identified in 32 of 60 lesions and no more than 2 sites were identified in 26 of 60 lesions, except for 2 phylloides tumors. Sensitivity, specificity, positive and negative predictive values and overall accuracy rates were, as for the "vascular sites" parameter, 78%, 96%, 94%, 85%, 88%, respectively; as regards the "peak systolic velocity" 81%, 86%, 89%, 75%, 83% respectively; as regards the "pulsatility index" 100%, 85%, 100%, 85%, 94% respectively.

Adult↗
PubMedDate not supplied

[Voluntary dilating pneumosinus (secondary hernia)].

In the present work authors describe an unusual case of pneumosinus dilatans caused willingly by a patient himself operated on a frontal-ethmoidal mucocele. They take the opportunity to summarize what it is known about the etiopathogenesis and the form of display of this uncommon disease.

Aged↗
PubMedDate not supplied

[The use and the potential of auditory electrophysiology in patients in posttraumatic coma].

21 patients in post-traumatic coma status were submitted to a auditory electrophysiological valuation together with EEG, TC, and "Glasgow Coma Scale" (GCS) with the purpose to obtain the relative prognostic value quoad vitam and quoad valetudinem. In particular it was carried out the brainstem auditory evoked potentials (ABR) and the auditory middle latency potentials (MLR and SSR-40 Hz). 12 patients survived and their clinical conditions were classified according to the "Glasgow Outcome Scale"; 9 of 21 patients died. With the aim of quoad vitam prognosis, the ABR showed a good reliability whereas GCS, EEG, TC and MLR proved not much usefulness. On the contrary the absence of SSR-40 Hz always coincided with the subsequent patients death. With the aim of GOS a meaningful relationship was found between the clinical outcome conditions from coma and the improvement in MLR and EEG.

Adolescent↗