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M Carreras

Publications and source records attributed to M Carreras.

At least 37 records · Page 2Linked to original sources
PubMed1988

Effect of vanadate on the glucose-1,6-bisphosphate synthase and glucose-1,6-bisphosphatase activities of phosphoglucomutase.

Phosphoglucomutase, in addition to catalyzing the interconversion of glucose 1-P and glucose 6-P, catalyzes both the synthesis of glucose 1,6-P2 from glucose monophosphate and either fructose 1,6-P2 or glycerate 1,3-P2, and the hydrolysis of glucose 1,6-P2. Vanadate inhibits the mutase activity, activates the synthase activities, and does not affect the phosphatase activity. These effects suggest that the "exchange" step postulated for the phosphoglucomutase pathway is specifically inhibited by vanadate.

Animals↗
PubMed1988

Metabolism of glucose 1,6-P2--III. Partial purification and characterization of glucose 1,6-P2 synthase from pig skeletal muscle.

1. Glycerate 1,3-P2-dependent glucose, 1,6-P2 synthase has been purified 2000-fold from pig skeletal muscle, with a yield of 75%. 2. The enzyme possesses fructose 1,6-P2-dependent glucose 1,6-P2 synthase and phosphoglucomutase activities, which represent 0.1 and 60% of the main activity, respectively. 3. Both glucose 1-P and glucose 6-P can act as acceptors of the phosphoryl group from glycerate 1,3-P2. 4. The Km values are 19 microM and 67 nM for glucose 1-P and glycerate 1,3-P2, respectively. 5. The enzyme is inhibited by glycerate 2,3-P2, fructose 1,6-P2, glycerate 3-P, phosphoenolpyruvate and lithium, the inhibition pattern varying with the compound.

Animals↗
PubMed1988

Apparent recurrence of hemolytic uremic syndrome in azathioprine-treated allograft recipients.

The present study describes 3 adult patients with hemolytic uremic syndrome (HUS) leading to chronic renal failure. Following renal transplantation, the 3 patients developed microangiopathic hemolytic anemia associated with acute rejection crises and graft failure. In 2 patients the renal histology of the transplanted kidney was consistent with HUS. It is concluded that, in adult patients, HUS may recur after renal transplantation and contribute to renal graft failure.

Adult↗
PubMed1988

Motor neuron disease in the province of Ferrara, Italy, in 1964-1982.

We carried out an intensive incidence, prevalence, and mortality survey of motor neuron disease (MND) in the province of Ferrara, northern Italy. Based on 72 patients, the mean incidence per year for the period 1964 through 1982 was 0.98 cases per 100,000. On December 31, 1981, the prevalence rate was 3.95 per 100,000. In the 19-year period the average mortality rate was 0.83 per 100,000 per year. The disease was more common in men, in individuals aged 50 to 70 years, and in residents in rural areas engaged in agricultural work. A retrospective case-control study, confirming a significantly higher frequency of MND in farmers and persons living in rural areas, revealed that the disease was more common in the lower social classes to which most unskilled and heavy laborers belong. In addition, a significantly increased risk for MND was found in patients with previous histories of trauma, but confounding variables may account for this association.

Adult↗
PubMed1988

Effects of vanadate and insulin on glucose 1,6-P2 and fructose 2,6-P2 levels in rat skeletal muscle.

Levels of glucose 1,6-P2 but not fructose 2,6-P2 were found decreased in skeletal muscle of alloxan-diabetic ketotic rats. Administration of both insulin and vanadate restored the altered values without affecting fructose 2,6-P2 concentrations. In normal rats, insulin increased muscle levels of both sugars, and vanadate decreased glucose 1,6-P2 without changing fructose 2,6-P2 levels. Enzymatic activities involved in glucose 1,6-P2 and fructose 2,6-P2 metabolism were not affected under any experimental condition.

Animals↗
PubMed1986

Effects of fructose 2,6-bisphosphate on phosphoglucomutase from plants.

Fructose 2,6-bisphosphate affects phosphoglucomutase from plant and animal sources in a similar way. As previously found with rabbit muscle phosphoglucomutase, fructose 2,6-bisphosphate cannot substitute for glucose 1,6-bisphosphate as a cofactor in the reaction catalyzed by phosphoglucomutase from potato tubers, pea seeds, and string-beans. In the presence of glucose 1,6-bisphosphate, fructose 2,6-bisphosphate inhibits phosphoglucomutase from potato tubers. Activation of phosphoglucomutase from plant sources by fructose 2,6-bisphosphate reported by others was probably due to contamination of the commercial preparation of fructose 2,6-bisphosphate by glucose 1,6-bisphosphate.

Journal Article↗
PubMed1985

Inhibition of phosphoglucomutase by fructose 2,6-bisphosphate.

Fructose 2,6-bisphosphate inhibits phosphoglucomutase. The inhibition is mixed with respect to glucose 1,6-bisphosphate and non-competitive with respect to glucose 1-phosphate. In contrast with fructose 1,6-bisphosphate and glycerate 1,3-bisphosphate, which also possess inhibitory effect, fructose 2,6-bisphosphate does not phosphorylate phosphoglucomutase. Fructose 2,6-bisphosphate preparations contain contaminants which can explain artefactual results previously reported.

Animals↗
PubMed1985

The frequency of multiple sclerosis in Italy: a descriptive study in Ferrara.

Results of intensive prevalence surveys on multiple sclerosis carried out in different small regions of Italy have suggested that this country falls into the high-frequency zone for the disease. To verify this hypothesis by studying a large population, we conducted intensive incidence and prevalence survey in the province of Ferrara, northern Italy (mean population, 386,000). Based on 128 patients, the mean incidence per year for the period 1965 through 1979 was 2.2 cases per 100,000. On October 24, 1981, the prevalence rate was 46.1 cases per 100,000. The results support the view that northern Italy is a high-risk area for multiple sclerosis.

Adolescent↗
PubMed1985

Predisposing factors in Bell's palsy: a case-control study.

The frequency of diabetes mellitus reported in subjects affected by Bell's palsy varies widely. In this investigation, a case-control study, we encountered a frequency of 24.8%. In addition, arterial hypertension and lipid disturbances were found to affect subjects with Bell's palsy more frequently than controls. These findings appear to suggest a primarily ischaemic pathogenesis for most cases of idiopathic peripheral facial paralysis. Furthermore, the finding of significantly lower taste impairment in diabetics than in non-diabetics with Bell's palsy may support the hypothesis of a vascular rather than a metabolic pathogenesis in these cases also. In fact, the vessels supplying the distal portion of the facial nerve, probably more affected in the diabetic patients in order to preserve taste sensation, have such a particular anatomical configuration that this might favour the onset of a diabetic small vessel disease which, in turn, would represent a factor of easier decompensation.

Adult↗
PubMed1985

Metabolism of glucose 1,6-P2. I. Enzymes involved in the synthesis of glucose 1,6-P2 in pig tissues.

Pig tissues show four enzymatic activities of glucose 1,6-P2 synthesis: (A) 2 [glucose 1-P]----glucose 1,6-P2 + glucose; (B) glucose 1-P + ATP----glucose 1,6-P2 + ADP; (C) glucose 1-P + fructose 1,6-P2----glucose 1,6-P2 + fructose 6-P; (D) glucose 1-P + glycerate 1,3-P2----glucose 1,6-P2 + glycerate 3-P. Brain is the tissue with highest capability of glucose 1,6-P2 synthesis. With the exception of skeletal muscle, activity "D" represents the highest activity of glucose 1,6-P2 synthesis. In muscle, activity "B" is the major activity. The existence of a specific glucose 1,6-P2 synthase which catalyzes reaction "D" is confirmed. Two peaks of such an enzyme are isolated by ion-exchange chromatography. There is an enzyme which specifically catalyzes reaction "C", not previously described. There is a glucose 1-P kinase not identical to phosphofructokinase.

Animals↗
PubMed1984

Muscle-nerve ephaptic excitation in some repetitive after-discharges.

We describe high frequency muscular repetitive after-discharges (MRDs), induced by maximal or near maximal electrical nerve stimulation, in 5 patients suffering from different peripheral neuropathies. No MRDs were observed at rest or during voluntary contraction. In all the MRDs the interval between the onset of the M wave and the onset of the MRD did not change in relation to the nerve stimulation point; double supramaximal stimulation with adequate delay, delivered at the same nerve site, could suppress the MRDs. From the electrophysiological features the authors suggest an interpretative model: the muscular electric field of the M wave could reexcite ephaptically an intramuscular axon, with defective repolarizing capacity, producing a muscle-nerve reverberating loop.

Adult↗
PubMed1984

Pattern electroretinogram in multiple sclerosis.

The pattern electroretinogram obtained in patients affected by multiple sclerosis were compared with those in a normal population. The pattern electroretinogram amplitude in multiple sclerosis optic neuritis frequently appeared normal, but pattern electroretinogram amplitude abnormalities were found in patients suffering from recurrent multiple sclerosis optic neuritis. Pattern electroretinogram examination appears a useful method in the differential diagnosis between axonal and demyelinating optic nerve impairment.

Adult↗
PubMed1983

The frequency of multiple sclerosis in Mediterranean Europe. An incidence and prevalence study in Barbagia, Sardinia, insular Italy.

Recent investigations on multiple sclerosis (MS) distribution in Italy, based on relatively small population groups, contradict the current thesis, derived from studies undertaken in populations exceeding 300,000, of a lower spreading of the disease in Mediterranean Europe. Intensive surveys on small populations strengthen the suggestion that Italy is a high-risk area, although MS studies based on prevalence rather than incidence could also be biased by geographic variables making prevalence unsuitable for comparing MS prevalence rates found in different years and/or zones. We report a further epidemiologic study in Barbagia, Sardinia, insular Italy, undertaken both to establish the MS incidence in the last 20 years, and to estimate a new prevalence rate. Based on 31 probable incident cases, the mean incidence per year for the years 1961-1980 was 2.9 per 100,000 (3.2 if age- and sex-standardized to the Italian population). On October 24, 1981, the prevalence per 100,000 was 65.3 (77.9 if standardized to the Italian population). These results confirm that in Barbagia, MS occurs more frequently than expected in a Mediterranean area, and give further support to the idea that MS frequency in Italy is similar to that established for most central and northern European countries.

Adolescent↗
PubMed1981

Multiple sclerosis in northern Italy. Prevalence in the province of Ferrara in 1978.

Most available Italian studies indicate that the prevalence of multiple sclerosis (MS) in Italy is lower than 20 per 100,000. Much higher prevalence figures, however, have been recently found in small communities in Sicily. On this basis, it has been suggested that the frequency the MS in Italy has been seriously underestimated and that the true prevalence for MS is probably similar to that established for northern European countries. This paper reports the results of a survey of MS in the various public health districts of the province of Ferrara. The public health districts are homogeneous medical units serving small populations and therefore represent ideal areas for epidemiological purposes. The total prevalence rate of probable MS for the whole province has been found to be at least 26.9 per 100,000. This result supports the view that the frequency of MS in Italy is higher than that indicated by most published studies, but not that Italy is an area of high risk for MS.

Adolescent↗
PubMed1980

Multiple sclerosis in southern Europe. A prevalence study in the sociosanitary district of Copparo, northern Italy.

The prevalence of multiple sclerosis (MS) in the Italian studies presently available is reported to be between 3.3 and 19.5 per 100,000. All these studies, however, have been undertaken in populations exceeding 300,000 and probably offer underestimates of MS frequency. Current sanitary organization in Italy is inadequate for epidemiological search and many patients with MS may be overlooked when large populations are studied. So, accurate estimates of MS frequency are possible only as a result of intensive surveys in small population groups. Prevalence figures of 53 and 32 per 100,000 have been recently reported by Dean et al. who studied the frequency of MS in small population groups in Sicily. The present study reports the results of a similar survey in the district of Copparo (population 45,153) in northern Italy. The prevalence of probable MS found in Copparo was 31 per 100,000. This result confirms the findings of Dean et al. in southern Italy and supports Dean's opinion that the true frequency of MS in Italy as a whole is higher than that indicated by the Italian studies.

Adult↗
PubMed1978

Ictal prosopagnosia and epileptogenic damage of the dominant hemisphere. A case history.

This case report concerns a patient whose episodes of prosopagnosia appeared to be epileptic manifestations arising from the left occipital lobe. The underlying pathology, as revealed by radiologic and surgical findings, was an atrophic-hypoplastic lesion of the left hemisphere, more prominent in the posterior sections, likely dating from early life. Removal of an arachnoidal cyst of the occipital pole and excision of the damaged gray matter were followed by the disappearance of the prosopagnosic seizures for the two years between the date of the surgical intervention and the publication of this article.

Adult↗