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Biomedical subjects

G Comi

Publications and source records attributed to G Comi.

At least 343 records · Page 19Linked to original sources
PubMed1993

Multiple deletions of mitochondrial DNA in a patient with periodic attacks of paralysis.

In this study multiple deletions of mitochondrial genome were found in a patient presenting with periodic attacks of paralysis. Morphological studies revealed mitochondrial abnormalities along with typical histopathological features of periodic paralysis. Southern blot and PCR analysis revealed multiple mtDNA deletions. Our patient could be affected by two unrelated diseases, idiopathic periodic paralysis and presymptomatic mitochondrial myopathy. Alternatively, mtDNA alterations and oxidative deficiency might express themselves phenotypically as periodic paralytic attacks, although this correlation has never been reported.

Biopsy↗
PubMed1993

Brain magnetic resonance imaging correlates of cognitive impairment in multiple sclerosis.

We evaluated the correlations between cognitive impairment, clinical and brain magnetic resonance imaging (MRI) findings in 100 patients with multiple sclerosis (MS). The performance on one or more neuropsychological tests was abnormal in 47% of the 64 patients who completed the entire neuropsychological battery; the cognitive impairment was mild in 14 (22%) and severe in 16 (25%). Performance on any single neuropsychological test was unrelated to clinical parameters (age, duration of the disease, disability). The neuropsychological performance of relapsing-remitting patients was better than in patients with a chronic-progressive disease. The mean scores for almost all the neuropsychological tests were significantly lower in patients with severe ventricular dilatation and corpus callosum atrophy than in patients in whom these structures were little affected. Mean scores for WMS, performance Intelligence Quotient (IQ), total IQ and Token Test (TT) were also significantly correlated with the widening of cortical sulci and total lesional scores. Our data support the contention that the involvement of pathways that are critical for a given cognitive process as well as the progression of the axonal degeneration and sclerosis seem to play important roles in the pathophysiology of cognitive dysfunction in MS.

Adult↗
PubMed1993

Absence of oligoclonally restricted immunoglobulins in tears from multiple sclerosis patients.

To study the extent of systemic immunodysregulation in multiple sclerosis (MS) we measured immunoglobulin (Ig)G, A, and M levels and studied their migrational properties after agarose isoelectric focusing in serum, cerebrospinal fluid (CSF) and tear samples from 18 MS patients, 17 patients with other neurological diseases (OND), and tears and serum samples from ten normal controls (NC). A slight elevation of total IgG, IgM and IgA levels was detected in tears from patients with MS and OND compared to NC. Of the five patients (two MS, three OND) that showed IgG oligoclonal bands (OCB) in tears, only one MS patient showed unique bands in tears not seen in the paired CSF and serum. We never found IgA, and IgM OCB in serum, CSF or tear samples. Our results suggest that polyclonal Igs are systemically elevated during chronic neurological inflammatory diseases. Oligoclonal Ig in MS, although occasionally detectable in tears, is mainly confined to the central nervous system and appears restricted to class G.

Adolescent↗
PubMed1993

Biometric Study of Acetoin Production in Hanseniaspora guilliermondii and Kloeckera apiculata.

Gas chromatographic analysis by direct injection of samples yielded quantitative data on acetoin content. Ninety-six strains of Hanseniaspora guilliermondii and Kloeckera apiculata were investigated for the ability to produce acetoin in synthetic medium and in must. High-level production of acetoin was found to be a characteristic of both species. In synthetic medium, the two species were not significantly different with respect to sugar utilization and ethanol or acetoin production. In grape must, the two species were significantly different (P = 0.001) in acetoin production and K. apiculata exhibited a significantly negative correlation between acetoin production and either sugar consumption or ethanol production. Use of selected apiculate yeasts in mixed cultures with Saccharomyces cerevisiae seems promising for optimization of wine bouquet.

Journal Article↗
PubMed1993

Lambert-Eaton myasthenic syndrome and polyneuropathy in a patient with epidermoid carcinoma of the lung.

We describe a patient affected by the Lambert-Eaton myasthenic syndrome, sensory motor axonal neuropathy and epidermoid carcinoma of the lung. Serum autoantibodies to voltage-operated calcium channels were detected. After lobectomy, voltage-operated calcium channel-related structures were demonstrated in the patient's tumor. By immunocytochemistry, the patient's IgG reacted with neural structures and particularly with intermediate filaments. We think that these autoantibodies may be implicated in the pathogenesis of the neurological symptomatology.

Aged↗
PubMed1993

Brain stem magnetic resonance imaging and evoked potential studies of symptomatic multiple sclerosis patients.

In this study we evaluated the sensitivity of neuroradiological and neurophysiological tests for detecting brain stem (BS) lesions in multiple sclerosis patients, since the recent introduction of the gradient motion rephasing technique has markedly increased the image quality of magnetic resonance imaging (MRI). From 50 MS patients (33 women and 17 men; mean age 35.9 +/- 8.3 years; mean duration of the disease 7.2 +/- 4.1 years) with clinical signs of BS involvement, brain MRI, BS auditory evoked potentials (BAEPs), and left and right median somatosensory evoked potentials (mSEPs) were obtained. BS MRI lesions were detected in 41 patients (82%); in 14 cases they were located in the medulla oblongata, in 55 in the pons, and in 24 in the midbrain. Single lesions were present in 20 patients, while two or more BS lesions were demonstrated in 21 patients; 30 patients had at least one lesion located close to the inner or the outer cerebrospinal fluid border. BAEPs were abnormal in 19 of the 50 patients (38%), and BS components of mSEPs were abnormal in 15 of 46 (33%). With combined use of these neurophysiological techniques, BS abnormalities were revealed in 24 patients (48%). Only 1 patient had neurophysiological BS abnormalities and normal MRI. Moreover, there was a good correlation (74%) between the clinical and MRI BS findings in the 23 patients with signs referable to focal neurological BS lesions. The concordances considering clinical and evoked potential reports were positive, but less marked.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Microbiological quality of artisanal ice cream.

In the course of the years 1990 and 1991, 396 samples of artisanal ice-cream had been collected from different ice-cream shops in Udine and province and analysed. All tested flavours contained aerobic germs, coliforms, Enterococci and yeasts in different quantities. In the analysed samples neither Salmonellae spp., nor Listeria monocytogenes nor Staphylococcus aureus were detected. Numerous species of coliforms and yeasts were randomly isolated and identified. The statistical analysis, used to compare the variables (flavour, month, year), showed significant differences among the samples analysed in the two years. In September, the means of the total aerobic count were significantly different from the ones of July and of August. No significant differences were noted in the means of coliforms, total aerobic counts and yeasts in the different flavours. The techniques for recovery of freeze-stressed coliforms in artificially contaminated samples of ice-cream showed that the three techniques, which use both selective and non-selective mediums, are better than those ones, which use only selective mediums. Lastly, with regard at the coliform values, the ice-creams tested have small-medium quality. In fact 26% of the ice-creams cannot be sealed, according to the Italian Ministry Ordinance (October 11, 1978).

Enterobacteriaceae↗
PubMed1992

Effects of hyperglycaemia on visual evoked potentials in insulin-dependent diabetic patients.

Multimodality evoked potentials frequently reveal subclinical involvement of the central nervous system in patients with insulin-dependent diabetes mellitus. We devised this study to evaluate the possible effects of acute hyperglycaemia on visual evoked potential (VEP) parameters in type 1 diabetic patients. A hyperglycaemic clamp (250 mg/dl for 180 min) was performed in ten patients. Monocular pattern reversal VEPs (check size 15', contrast 50%) were recorded before, and every 30 min after the start of the clamp. Basal VEP latencies and amplitudes were normal bilaterally in nine patients. No significant changes in pattern reversal and flash VEP parameters were observed after the induction or during the clamp period. None of the neurophysiological parameters evaluated during the test was related to the duration of the disease, the basal VEP latency or amplitude or the presence of retinopathy. Our data suggest that the neurophysiological abnormalities detected in insulin-dependent diabetic patients are due to structural involvement of the central nervous pathways and not to functional damage induced by acute short-term hyperglycaemia.

Adult↗
PubMed1992

Relationship between corpus callosum atrophy and cerebral metabolic asymmetries in multiple sclerosis.

Corpus callosum (CC) atrophy by magnetic resonance imaging (MRI) is a common finding in multiple sclerosis (MS). In order to examine the relationship between CC atrophy and cortical brain metabolism, we compared the cerebral metabolic rates for glucose (CMRglc), measured by positron emission tomography (PET), of 8 MS patients with evidence of CC atrophy on midsagittal MRI, 8 MS patients without CC atrophy and 10 healthy controls. Results showed no significant differences in supratentorial CMRglc absolute values between the three groups, although a slight metabolic reduction was observed in both MS groups compared with normal controls. By contrast, only patients with CC atrophy showed greater directional metabolic asymmetry than normals, the left frontal, temporal and parietal association cortices being significantly lower than the right. Predominant left hemispheric metabolic reductions were not accompanied by a corresponding left-sided predominance in the extent of MRI-detected demyelinating lesions. Therefore our data suggest that CC atrophy interfers more with left than with right metabolic function.

Adult↗
PubMed1992

The role of transcranial Doppler in carotid artery surgery.

In order to evaluate the usefulness of transcranial Doppler (TCD) in carotid artery surgery, 90 patients who underwent carotid endarterectomy were studied. Transcranial Doppler was performed preoperatively with digital compression of the carotid artery and intraoperatively at the time of cross-clamping, together with routine EEG monitoring. The percentage residual middle cerebral artery velocity (%MCAV) during carotid artery compression or cross-clamping was considered. The intraoperative %MCAV at cross-clamping was compared with the values obtained in the preoperative examination during the compression test and with the EEG data; the EEG records were blindly reviewed by a neurologist and divided into three groups: group A, normal; group B, moderate anomalies and group C, major anomalies. There were no significant differences between preoperative %MCAV (compression test) and intraoperative %MCAV (cross-clamping) by separate analysis of the data related to systolic, diastolic and mean velocity. The systolic, diastolic, mean %MCAV and the Gosling index after cross-clamping were then compared with the EEG data: no significant differences were seen between groups A and B; on the other hand, in all patients with major EEG anomalies (group C) the %MCAV at TCD was reduced to 0. In conclusion, preoperative TCD associated with carotid artery compression appears a safe and useful way of identifying patients at risk of cerebral ischaemia during carotid artery cross-clamping. Patients with no residual flow at intraoperative TCD need to be considered as presenting a very high risk of ischaemia and in this group the use of a shunt is mandatory.

Aged↗
PubMed1992

Normal tissue plasminogen activator and plasminogen activator inhibitor activity in plasma from patients with type 1 diabetes mellitus.

The fibrinolytic system was investigated in 38 patients (21 males and 17 females) affected by type 1 diabetes mellitus (18 free from complications, 10 with retinopathy, and 10 with autonomic neuropathy) and in 8 healthy controls. Two separate fibrinolysis-stimulating tests were done: standardized venous occlusion and 1-desamino-8-D-arginine vasopressin infusion. Plasma tissue plasminogen activator antigen and activity and plasma plasminogen activator inhibitor activity were measured. All the patients were in good metabolic control (mean HbA1c 7.4%, range 6.1-8.0%). No significant differences were observed either between the diabetic patients and the control subjects, nor among the subgroups of diabetic patients. The fibrinolytic system is probably not involved in type 1 diabetes mellitus.

Deamino Arginine Vasopressin↗
PubMed1991

Neurophysiological study of the effect of combined kidney and pancreas transplantation on diabetic neuropathy: a 2-year follow-up evaluation.

Previous study have reported a significant improvement of peripheral neuropathy following combined pancreas and kidney transplantation attributed to improvement of blood glucose control by some authors and to elimination of uraemia by others. To asses the specific role of uraemia and hyperglycaemia in neuropathy, 16 diabetic uraemic patients with combined pancreas and kidney transplantation were compared to 9 diabetic patients with a renal graft only. Neurophysiological studies of peripheral neuropathy included ulnar and deep peroneal nerve motor conduction velocity, median and sural nerve sensory conduction velocity were performed at baseline and 1 and 2 years after transplantation. One year after transplantation mean nerve conduction velocity significantly improved in both groups. However, changes were statistically significant in the kidney-pancreas group only. At the 2 year follow-up nerve conduction velocity had increased further in the pancreas-kidney group only. These data suggest that improvement of nerve conduction velocity following pancreas and kidney transplantation is predominantly due to the long-term euglycaemic state.

Adult↗
PubMed1991

Appearance and localization of dystrophin in normal human fetal muscle.

We studied the localization of dystrophin in normal human fetal muscle by immunohistochemistry. Our results show the appearance of dystrophin at week 11 and a progressive organization of the protein along membrane in the following weeks of gestation. At week 22 almost all fibers show a clear membrane immunostaining. Concomitant analysis of muscle fiber-type composition reveals no correlation between progressive appearance of dystrophin and muscle fiber-type differentiation. Our findings suggest that synthesis and localization of dystrophin in developing human skeletal muscle is time-related and probably independent of neuronal influences.

Dystrophin↗
PubMed1991

Paraclinical tests in acute-onset optic neuritis: basal data and results of a short follow-up.

Up to now it is still doubtful whether there is a real risk of developing multiple sclerosis (MS) after initial monosymptomatic optic neuritis (ON). In this study we evaluated 43 patients with isolated acute-onset ON, in order to demonstrate the presence of oligoclonal bands (OBs) in the cerebrospinal fluid (CSF) and any additional clinically silent central nervous system (CNS) lesions. All examinations were performed from 5 days to 4 months (mean 43 days), from the onset of visual disturbances. Brain magnetic resonance imaging (MRI) detected white matter areas with increased signal in 21 patients (49%), while somatosensory and brainstem auditory evoked potentials revealed CNS abnormalities in only 5 patients (12%). OBs were present in the CSF of 20 patients (46%). Visual evoked potentials were abnormal in 39 patients (91%). Seven out of the 37 patients (19%) with at least one year follow-up, (mean duration of the follow-up = 32 months, range = 12-74), developed clinically definite MS (CDMS). All 7 patients had positive brain MRI and 6 had positive CSF examination at the basal evaluation. Our data suggest that MRI and CSF-OBs are the most reliable means of identifying patients with isolated ON who subsequently develop CDMS. They may therefore have a predictive value in defining MS risk.

Acute Disease↗
PubMed1991

Glucose-6-phosphate dehydrogenase Lodi844C: a study on its expression in blood cells and muscle.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency was found in erythrocytes, lymphocytes and muscle of an Italian male, whose family has lived for at least three generations in Lodi (Lombardy, northern Italy). The subject was hospitalized for myalgia and dark urine after intense physical exercise, but no sign of anemia and chronic hemolysis were present at rest. Family studies revealed that the mother and the maternal aunt had the same enzymopathy. The enzyme-specific activity in red blood cells was 15% of control and the kinetic properties were the following: slower electrophoretic mobility; biphasic pH activity curve; slightly reduced thermal stability, and increased utilization of the substrate analogs. The analysis of our patient's DNA showed a G----C mutation at nucleotide 844 which causes an Asp----His amino acid change in position 282. This is the same mutation found by De Vita et al. in the G6PD Seattle-like variant. However, by following a new convention, we labelled our variant as G6PD Lodi844C. As far as the muscle is concerned, we found that the enzyme-specific activity in this tissue was 14% of control values, but cultured myotubes and myoblasts revealed a normal level of G6PD as well as skin fibroblasts. On the contrary in the same type of cultured cells obtained from G6PD Mediterranean subjects, the G6PD activity was about 20% of normal. Our results complete the characterization of this mutant enzyme, demonstrate the expression of the deficit in muscle and describe the enzyme behaviour in cultured cells.

Adult↗
PubMed1991

Evaluation of an enzymatic method for fast identification of Listeria spp. in cheese and meat products.

Listeria-Tek ELISA was compared with conventional cultural procedure of FIL/IDF (Federation International de Laiterie/International Dairy Federation) modified by us. The ELISA assay is able to detect Listeria innocua, Listeria monocytogenes, Listeria murrayi and Listeria welshimeri, after 48 h in artificially contaminated cheeses. No specific reactions, no false positive or negative were detected and the assay has a high correlation with the conventional method used in this research. We also analyzed meat products and cheeses and identified Listeria spp. and Listeria monocytogenes serotypes. In 313 food samples examined there were only 3 false positives. With ELISA Kit we obtained 0.9% more than with the cultural method and the percentage of false positives is 1.6%. So in commercial products the total absence of false negatives demonstrates the great sensitivity of the method in respect to investigated microorganisms. As determined by cultures 218 samples contained 47 Listeriae monocytogenes, 67 Listeriae innocua, 21 Listeriae welshimeri, 7 Listeriae ivanovii, 3 Listeriae murrayi and 3 Listeriae denitrificans. Listeria monocytogenens includes serotypes 1 (13) and serotypes 4 (14). 20 Listeriae monocytogenes were serotyped by polyantisera Difco (Detroit, Michigan).

Animals↗
PubMed1991

Multicenter trial with ubidecarenone: treatment of 44 patients with mitochondrial myopathies.

Fourty four patients with mitochondrial myopathies were treated with Ubidecarenone (CoQ10) for six months in an open multicentric trial. No side effects due to the drug administration were observed. Sixteen patients showing at least 25% decrease of post exercise lactate levels were selected as responders. Responsiveness was apparently not related to CoQ10 level in serum and platelets or to the presence or absence of mtDNA deletions. The responders were further treated for 3 months with CoQ10 or placebo in the second blind part of the trial; no significant differences between the 2 groups were observed. It is not clear why CoQ10 had therapeutic effects in some patients and not in others with the same clinical presentation and biochemical defect, and we failed to identify candidate responders before treatment. At the dosage of CoQ10 used in the study (2 mg/kg/day) the therapy requires long administration time before a response is demonstrable.

Adolescent↗