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Biomedical subjects

G Sandrini

Publications and source records attributed to G Sandrini.

At least 91 records · Page 5Linked to original sources
PubMed1982

Membrane processes in myotonic dystrophy during in vitro aging of erythrocytes.

The present communication is devoted to investigating the possibility that in myotonic dystrophy (MyD) a decreased ATP utilization by the membrane may produce modifications in glycoprotein structure and/or in the supramolecular arrangement of some membrane proteins. The study was carried out a) by determining the membrane sialic acid content and the cellular ATP concentration in 10 cases of MyD, b) by evaluating the structural modifications of membrane glycoproteins occurring during in vitro incubation, c) by testing the presence on the membrane of high molecular weight aggregates of proteins, and d) by evaluating the distribution of hydrophobic and hydrophilic domains of the membrane by using 1-anilino-8-naphthalene sulfonate (1,8 ANS) as a fluorescent probe. Our evidence suggests that the ATP concentration and membrane sialic acid content are within normal values. Only in two cases did structural modifications of membrane glycoproteins occur while the supramolecular assembly of membrane proteins could be considered normal. The fluorescent probe behaviour after in vitro aging was indicative of a decreased polarity of its environment.

Adolescent↗
PubMed1981

An ocular myopathy with glycogen storage and abnormal mitochondria in muscle fibres. Histochemical and ultrastructural findings.

The case of a 66-year-old woman with progressive external ophthalmoplegia and involvement of the proximal muscles of the upper and lower limbs is described. EMG examinations show signs of myopathic involvement. Histochemical and biochemical studies exclude a primary defect in glycogenolysis. The authors stress the peculiarity of the histochemical findings, characterized by the rare associated appearance of both mitochondrial changes and glycogen accumulation in muscle fibres. The most prominent ultrastructural findings are evidence of increased glycogen, usually present in vesicles or in mitochondria, and changes in number, size and structure of mitochondria. Quantitative biochemical examination of muscle homogenates confirmed the increased content of glycogen in muscle fibres.

Aged↗
PubMedDate not supplied

[Automatic analysis of M.U.A.P.s (author's transl)].

The authors have studied the Motor Unit Action potentials derived from Extensor Digitorum Brevis and tibialis anterior muscles in normal subjects, using a new method of automatic analysis by means of a digital computer. In the light of the results they have obtained they discuss the validity and the sensitivity of the method as well as the opportuneness of the choice of the muscular region to examine when it comes to determining subclinical or "border-line" cases.

Action Potentials↗
PubMedDate not supplied

The position of the head in space: a kinematic analysis in patients with cervical dystonia treated with botulinum toxin.

Many instruments have been employed in recent years in order to quantify the posture and motion of the head in normal and pathological subjects. Evaluations of this type present many difficulties related to the influence of individual and external factors and to the accuracy of the system used. In patients with cervical dystonia (CD) the only rating scales currently used are semi-quantitative and subjective. More precise information on disease severity and response to the treatment is needed. Posture and motion of the head were evaluated by means of ELITE motion analyser (BTS, Milan, Italy) in 6 patients with the left laterocollis form of CD undergoing treatment with botulinum toxin (BTX). The method emerged as very useful for the quantification of the therapeutic response (which was more marked in motion than in posture). We found an inverse relationship between the degree of motion improvement and the restriction of motion before treatment.

Adult↗
PubMedDate not supplied

Electrophysiological study on jaw-opening reflex recorded from digastric muscle in Parkinson's disease and primary cranial dystonias.

We investigated digastric reflex excitability in normals and in patients with extrapyramidal disorders such as primary cranial dystonias and Parkinson's disease. Relationships between exteroceptive suppression of masseter muscle and digastric reflex were also investigated in some cases. Digastric reflex hyperexcitability was observed in dystonic patients when compared to normals and parkinsonian patients. Furthermore, some patients with cranial dystonia presented absence of exteroceptive suppression reflex in masseter muscle with enlarged digastric response. These results indicate hyperexcitability of the digastric reflex and abnormal agonist-antagonist muscle co-contraction in chewing reflexes of patients with cranial dystonias. This shows that digastric reflex is an important electrophysiological investigation to explore the physiopathological mechanisms of primary cranial dystonias.

Aged↗
PubMedDate not supplied

[Prevalence of primary headache related to work activity in a group of hospital workers undergoing periodic visits (D. Lgs. 626/94 s.s.m. ed i.)].

Since headache is one of the most frequent complaints in clinical practice, its burden in terms of the both social cost and individual sufference is considerable. Headache is a frequent cause of absence from work and decreased productivity; it is therefore clear that investigating its possible relationship with working conditions represents a topic of increasing interest for the scientific community. This study was aimed at identifying specific occupational factors able to modify the prevalence of headache in a population of hospital workers undergoing periodic examinations. It was indeed suspected that the hospital environment could be per se a predisposing factor for headache onset, due to the considerable impact of stress on such working environment. The results obtained suggest that specific occupational conditions such as shift work and P.C. use may play an important role in headache development even in the presence of a wide number of professional risk factors.

Adult↗
PubMedDate not supplied

[Headache as "sentinel" symptom in personnel involved in the preparation and administration of antineoplastic drugs].

The increased prevalence of neoplastic diseases observed over the last years has resulted for in more frequent operations of preparation and administration of antiblastic drugs performed by the medical personnel. In this study, we examined a group of subjects involved in the preparation of ACNU, Methotrexate, Novantrone, Vincristine, Cyclophosphamide, Carboplatinum, Mythoxantrone, in order to elucidate whether headache may represent an early symptom of exposure to these products. At the same time, we measured the degree of pollution in the air surrounding the vertical laminar flow aspiration cabinet used for drug preparation. The 66.6% of the 12 subjects studied, 9 females and 3 males, complained of headache. However, the environmental detection using high performance liquid chromatography coupled with triple quadrupole mass spectrometry (HPLC/MS/MS) gave negative results with respect to a possible environmental damage. These findings suggest that headache is the onset symptom of the toxic effect of antiblastic chemiotherapics in the medical personnel involved in drug preparation and administration.

Adult↗
PubMedDate not supplied

Cognitive and neuroradiological findings in myotonic dystrophy.

Cognitive functions were investigated in 37 patients with myotonic dystrophy (MD) and correlated with clinical and neuroradiological variables. The whole cognitive performance was at a low-average level; in about 1/3 of the subjects, in fact, the scores at the neuropsychological tests were below the normal range. There was a consistent trend for patients with inheritance on maternal side to perform worse on Wechsler verbal score and to present cerebral atrophy. In 7 out of 12 subjects focal white matter lesions were found at nuclear magnetic resonance. The significance of these findings and its relation to cognitive performance are discussed.

Adult↗
PubMedDate not supplied

Local venous lactate changes and spectral analysis of surface EMG during fatiguing isometric efforts in intrinsic hand muscles.

In this study relationships between local venous lactate concentrations and power spectrum changes in surface EMG due to fatiguing isometric contractions were investigated. Two different isometric efforts of the opponents pollicis muscle, 25% and 50% of maximum voluntary contraction, were examined. In 25% of maximum voluntary contraction no changes in local venous lactate were observed, whereas mean power frequency values of surface EMG shifted significantly towards lower frequencies. On the contrary, in 50% of maximum voluntary contraction lactate significantly increased and was related to the mean power frequency shifts of the surface EMG. These data suggest that lactate plays a role in muscle fatigue only in a limited intensity range of isometric muscle contractions.

Adult↗
PubMedDate not supplied

The trigeminal pupillary reflex as a model of vegetative-nociceptive interaction: physiological and clinical aspects.

The study of pupil response to stimuli applied at the corneal level is particularly interesting for the study of integrative sensory-vegetative functions in both physiological and clinical research. In the present study we tried to evaluate and describe pupil response to quantified corneal stimuli in 7 healthy subjects by means of a binocular TV pupillometric device. The pupil response to corneal stimuli was bilateral, direct and consensual. It was characterized by a biphasic progression with an initial response in mydriasis and a later miotic component which was smaller, slower and of longer duration. A direct correlation was observed between the intensity of the stimulus applied and the extent of the mydriasis and between the intensity of the stimulus at the corneal level and the length of the mydriatic response.

Adult↗