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M Papini

Publications and source records attributed to M Papini.

At least 73 records · Page 4Linked to original sources

Scrapie strain infection in vitro induces changes in neuronal cells.

PC12 cells, in the presence of nerve growth factor (NGF), support replication of the mouse-derived scrapie strains 139A and ME7, with the former yielding 100-1000-fold higher levels of infectivity. Infectivity remained cell-associated and cells did not show any gross morphological alterations, although changes were observed by electron microscopy in the form of an increased number of lipid droplets in 139A-infected cultures. Analysis of phospholipid metabolism in 139A infected cells indicated that scrapie replication did not change the inositol phosphate levels, but did stimulate phosphoinositide synthesis. Replication was not detected in PC12 cells infected with either the hamster-derived 263K or rat-derived 139R scrapie strains. Since scrapie-infected cultures did not exhibit cell death or any gross changes, any scrapie-induced effects would probably be manifested in nonvital cellular functions. When compared to controls, infection with the 139A scrapie strain resulted in decreased activity of the cholinergic pathway-related enzymes, as well as the GABA synthetic pathway; however, the adrenergic pathway was unaffected by scrapie infection. The effects of the 139A scrapie strain on the cholinergic system appeared to be dose-dependent and were first detected prior to the detection of scrapie agent replication in these cells. No neurotransmitter-related enzymatic changes were detected in 263K- or 139R-infected PC12 cells. The enzymatic changes observed in ME7-infected PC12 cells and in Chandler agent-infected mouse neuroblastoma cells suggest that the significant changes in neurotransmitter levels in cultures exhibiting low infectivity titers must involve factors other than, but not excluding, replication of the agent. The role of additional factors is also suggested in studies of protein kinase C activity in 139A- and 139R-infected PC12 cells. These studies emphasize the value of the PC12 cell model system in examining the scrapie strain-host cell interaction and, in addition, support the concept of variation among scrapie strains.

Acetylcholinesterase↗

Tinea capitis in infants less than 1 year of age.

Tinea capitis is the most frequent manifestation of dermatophyte infection in children, but because it is rare in the first months of life it is often misdiagnosed. Here we report 15 cases of tinea capitis observed in Italy in infants less than 1 year of age. There were 10 boys and 5 girls (mean age 6 months). Diagnosis was confirmed by mycologic examination. Microsporum canis was isolated in nine cases and Trichophyton mentagrophytes in three. These 12 infants were Italian and animals were the source of infection. Trichophyton erinacei was isolated in one Italian infant, and the source was soil. In the other two cases, Trichophyton tonsurans and Trichophyton violaceum were isolated; these infants were from Central America and India, respectively, and had contracted the infection from humans. All achieved clinical and mycologic recovery after systemic and topical antimycotic therapy.

Age Factors↗

Cutaneous toxoplasmosis.

Nine patients with cutaneous toxoplasmosis had slowly regressing erythema-multiforme-like eruptions or lichenoid, papulonodular and purpurictelangiectatic disorders. The most common histologic finding was subacute histiolymphocytic perivasculitis with frequent demonstration of the parasite. Another group of patients showed similar clinical and histological findings, but the parasite was not evidenced in these.

Adolescent↗

Sjögren's syndrome: a retrospective review of the cutaneous features of 93 patients by the Italian Group of Immunodermatology.

OBJECTIVE: Various cutaneous manifestations have been described (xerosis, eyelid dermatitis, angular cheilitis, cutaneous vasculitis and annular erythema) in Sjögren's syndrome (SS), but so far only three studies on large numbers of SS patients have been carried out. The frequency of cutaneous manifestations and their association with specific clinical or immunological parameters have never been studied. The aim of the Italian Group of Immunodermatology was to evaluate these associations in a large number of SS patients. METHODS: A retrospective review was performed on 93 patients with SS followed over a ten-year period (1990-2000) at 6 Italian dermatological centers. They were subdivided into two groups, 62 with primary SS and 31 with secondary SS, and the frequency of cutaneous manifestations and specific antibodies was determined and compared between them. RESULTS: We found significantly higher levels of xerosis (p = 0.009) (56.4% versus 25.8%) and angular cheilitis (p = 0.017) (38.7% versus 16.1%) in primary SS patients than in those with secondary SS. A significant association of xerosis with anti-SSA + SSB (p = 0.033) antibodies was also demonstrated. Eyelid dermatitis and pruritus were common but less specific cutaneous symptoms. Annular erythema was found more often in primary (6.45%) than in secondary (3.2%) SS and was associated with SSA + SSB antibodies in 75% of the cases. Cutaneous vasculitis was present in 30.6% of primary SS (manifesting as palpable purpura in 84%) and in 29.3% of secondary SS cases. CONCLUSION: Xerosis is the most frequent and characteristic cutaneous manifestation of primary SS. It is not linked to decreased sebaceous or sweat gland secretion, but more probably to a specific alteration of the protective function of the stratum corneum. Angular cheilitis is a common but less specific skin lesion in SS and is associated with xerosis and xerostomia.

Adult↗

[CNV and SEP in shoe-industry workers affected by neuropathy due to toxic effects of adhesive solvents (author's transl)].

The sensitivity of the CNV and somatosensory evoked potentials (SEP) was assessed in shoe industry workers suffering from neurotoxic effects of adhesive solvents. We have examined 21 patients with clear electroneuromiographic and clinical signs of polyneuropathy as well as EEG signs of diffuse brain damage. 10 normal volunteers served as a control group. The maximal motor conduction velocity (MMCV) was considerably reduced in all patients. The maximal sensory conduction velocity (MSCV) was in the lower normal range (or borderline) in 12 patients, whereas in 9 or more severe decrement was detected. In comparison with normal subjects, none of the patients showed clear differences in latency or amplitude of SEP components (p always greater than .2). It was very easy to elicit CNVs over all areas explored and all the 10 patients showed normal characteristics. These results, therefore, suggest that CNV and SEP are not helpful for an early diagnosis of toxic effects of the solvents on the function of the central and peripheral nervous system.

Adolescent↗

[Event-related slow potentials (ERSPs) of the brain in cases of temporal psychomotor and petit mal status].

Two cases have been studied by means of the usual method for eliciting CNV (S-1.5 OR 1 SEC-S-operant response) during and after the end of an episode of prolonged epileptic twilight state with almost continuous strictly unilateral temporal lobe discharge. From the clinical viewpoint in both cases the twilight state, lasting respectively about 12 and 48 hours, was characterized by a slightly clouded consciousness and moderate impairment of awareness and of psychic performances, at times associated with simple and complex psychomotor automatism and hallucinations. The EEG recorded an almost continous left temporal discharge of pseudorhythmic mixed slow waves and sharps. The third case had typical prolonged petit mal states with continuous spike-and-slow-wave activity, impaired intellectual and motor performances (very long reaction time etc.). In this patient for eliciting ERSPs, besides the standard method, we have used a paradigm in which S consisted of a colored slide, with various semantic contents, remaining visible for 5 seconds on a screen. At the trials of the standard paradigm during the epiliptic twilight state, all patients showed they had understood the signal to interrupt (S loud repetitive tone) in the shortest time possible and could clearly distinguish them from the S. The operant response was almost always made with sufficient precision and sometimes with fairly short reaction time, especially by the patients with temporal psychomotor status. During the episodes of prolonged clouded consciosness in all series of trials administered to the patients, no negative slow potential shifts were observed in the averaged EEG recordings obtained from F-T, F-T or F, FCZ and referred to to linked mastoids. On repetition of the examinations some time after the end of the epileptic twilight state, fairly normal ERSPs were obtained in all cases. Taking also into account the results of previous researches, these studies show that the temporal lobe and "centrencephalic" epileptic discharges, under certain conditions, may influence negatively the neurophysiological mechanisms which contribute to the information of complex contingent connections and which also underly the particular attentional, cognitive and sensorimotor functions involved in the inhibiting the appearance of ERSPs probably related to more specific perceptual and integrative functions. Some AA. maintain that negative slow potential shifts express the functional activity of the brain structures, particularly of determined cerebral cortex regions, involved not only in attentional, perceptual, cognitive and psychomotor functioning, but also in information processing (memory recording mechanism). Hence, the negative influence of prolonged temporal lobe or meso-diencephalic epileptic discharges on these structures may explain the almost complete amnesia that patients generally show at the termination of this kind of twilight state.

Adult↗

Late infantile neuroaxonal dystrophy. An unusual case with predominantly myoclonic-epileptic symptomatology.

A case of infantile neuroaxonal dystrophy (I.N.A.D.) with late onset is described with protracted course and predominant myoclonic-epileptic symptomatology. A girl of 13 years died in myoclonic-epileptic state. She had suffered from a mild cerebellar deficit, slight intellectual impairment and increasing myoclonic attacks since the age of 5 years. A similar neurological syndrome, beginning at almost the same age, occurred in her younger brother who died at the age of 11 years from acute hepatic failure (without autopsy). Histological examination of the CNS in the girl revealed a diffuse neuroaxonal dystrophy, some areas of spongy degeneration in the cerebral and cerebellar white matter, cortical atrophy of cerebellum accompanied by demyelination of the spinocerebellar tracts, the fasciculus gracilis and the cortico-bulbar tracts. Such histological features are in keeping with those of I.N.A.D. or Seitelberger's disease. The clinical features, however, differ considerably from the latter as well as from Hallervorden-Spatz's disease and seem to belong, instead, to the group of progressive myoclonus epilepsies. In the differential diagnosis of these rare conditions, therefore, also the I.N.A.D. ought to be considered.

Adolescent↗