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Biomedical subjects

D Schiffer

Publications and source records attributed to D Schiffer.

At least 127 records · Page 7Linked to original sources
PubMed1987

Hereditary motor and sensory neuropathies: a genetic and epidemiological study in the province of Turin, Italy.

A clinical, genetic and epidemiological study of hereditary motor and sensory neuropathies (HMSN) was performed in the province of Turin, Italy. The patients were allocated to 5 groups, according to genetic and electroneurographic features. The high proportion of males among recessive and sporadic cases in the present series may suggest the existence of a recessive X-linked form of the disease. The crude prevalence rate was 3.18 (+/- 0.72)/100.000 population for all cases. The slow progression rate and the frequently mild symptoms of the disease, already suggested in literature, are confirmed by the analysis of the survival curves of the cases.

Adult↗
PubMed1987

Chondroitin, chondroitin 6-sulphate, chondroitin 4-sulphate and dermatan sulphate proteoglycans in normal and pathological human muscle.

Chondroitin, chondroitin 6-sulphate, chondroitin 4-sulphate and dermatan sulphate proteoglycans were immunolocalized by monoclonal antibodies applied to human muscle sections digested with chondroitinase. In normal muscle the 4 proteoglycans presented a different extracellular localization: unsulphated chondroitin sulphate (chondroitin) was present in the endomysium and around capillaries, chondroitin 6-sulphate in the basal membrane zone, chondroitin 4-sulphate in the vessel adventitia, in the endomysium around capillaries and, to a lesser degree, in the perimysium, dermatan sulphate in the perimysium and, to a lesser extent, in the vessel adventitia and in the endomysium around capillaries. The enlarged endomysium of pathological muscle contained chondroitin and chondroitin 4-sulphate. Chondroitin 6-sulphate and dermatan sulphate did not seem present in the increased connective tissue. No peculiar pattern was observed in the various neuromuscular diseases studied. The specific extracellular distribution, the different biochemical composition and the different ability to bind to other extracellular components suggest a different biological role of these compounds. Chondroitin 6-sulphate is a component of a highly specialized extracellular structure, namely basal membrane. Chondroitin and chondroitin 4-sulphate participate in the composition of actively changing extracellular matrix such as the endomysium in pathological muscle. On the other hand, dermatan sulphate is a constituent of the perimysium that is a more static extracellular structure.

Antibodies, Monoclonal↗
PubMed1987

Phenotypic and genotypic heterogeneity of dominantly inherited amyotrophic lateral sclerosis.

Twenty-seven cases of hereditary amyotrophic lateral sclerosis (ALS), belonging to 8 families, are reported. The analysis of the pedigrees suggests an autosomal dominant transmission, apparently with incomplete penetration. The mean age at onset of symptoms was 50.3 (SD 12.4) years. The mean duration of the disease was 31.2 (SD 20.4) months, ranging from 9 to 86. The median survival time was 24 months. The degree of variation of some quantitative characters, both within and among families, was statistically analyzed. The results support the hypothesis of a phenotypic and genetic heterogeneity of autosomal dominant transmitted ALS.

Adolescent↗
PubMed1987

42-hour methotrexate infusions as relapse therapy for childhood malignancies: toxicity and efficacy of 109 infusions.

Thirty-six children and adolescents received 42-h methotrexate (MTX) infusions in doses of 5.5-22 g/m2 as a single drug or as part of a combination chemotherapy for relapsed childhood leukemias or solid tumors. In a total of 109 courses serum MTX concentrations were maintained at 2 x 10(-5) -2 x 10(-4) M for 42 h before leukovorin rescue was started. There were responses in one of two hemangiopericytomas, two of five Ewing's sarcomas, and six of eight rhabdomyosarcomas. In ALL, NHL, and neuroblastomas, responses were seen with 42-h MTX infusions as part of a combination chemotherapy. The major toxicities were mucositis in 45%, nausea and vomiting in 35%, and hepatic toxicity in 25% of the courses. Bone marrow depression as well as neuro- and nephrotoxicity were rare. Long-term MTX infusions in high doses are strongly recommended for the treatment of relapsed childhood malignancies because of their efficacy and mild toxicity.

Adolescent↗
PubMed1986

Glial fibrillary acidic protein and vimentin in the experimental glial reaction of the rat brain.

Glial reaction has been studied in the rat by the immunohistochemical demonstration of glial fibrillary acidic protein (GFAP) and vimentin (VIM) in two experimental conditions. The first was represented by a necrotic cerebral lesion obtained by laser irradiation and the second by the development of experimental tumors induced by transplacental ethylnitrosourea. Reactive astrocytes develop not only in the proximity of the lesion but also distant from it. The intensity of the glial response seems to depend upon the normal distribution of astrocytes and the perilesional edema. GFAP decorates all the reactive astrocytes, whereas VIM is positive only in those at the edges of the lesion. The significance of the different responses in the two models and between the two intermediate filaments is discussed.

Animals↗
PubMed1986

Anaplasia and heterogeneity of GFAP expression in gliomas.

GFAP (glial fibrillary acidic protein) distribution was investigated in selected areas of glioblastomas and astrocytomas. The proliferating cell population of glioblastomas was GFAP negative and contained many mitoses which were also negative. The old, deeply located areas were composed of cells with visible cytoplasm, intensely GFAP-positive; mitoses in these areas were both GFAP-positive and negative. GFAP-positive reactive astrocytes, once trapped in the tumor, were no longer distinguishable from positive tumor cells. They sometimes contained mitoses. In astrocytoma, anaplasia was due to the development of a GFAP-negative population with negative mitoses. The problem of dedifferentiation and differentiation of malignant gliomas in discussed taking into account the possibility that malignancy may be due to increasing mutation rates of tumors. The problem of redifferentiation of already dedifferentiated cells is also discussed.

Anaplasia↗
PubMed1986

Simultaneous and successive localization of two antigens in the same tissue section using 3,3'-diaminobenzidine and 1-naphthol basic dye.

We describe two procedures for the simultaneous and successive localization of two antigens in the same tissue section. In the simultaneous staining procedure, the first antigen was localized using 3,3'-diaminobenzidine (DAB), while the second antigen was stained using the 1-naphthol basic dye (1-NBD) method. The colour of the second antigen depended on the basic dye used, and no mixing of colours was observed when the two antigens were localized in different cells or structures. However, sequential double staining proved to be more convenient for the demonstration of two antigens in the same cell. In this procedure, the first antigen was stained using 1-NBD, and the interesting microscopic fields were photographed. The basic dye was then completely removed, and the second antigen was stained using DAB.

3,3'-Diaminobenzidine↗
PubMed1986

Immunohistochemical study of chondroitin sulfate in human gliomas.

A polyclonal rabbit antiserum was utilized to localize chondroitin sulfate in human gliomas. Tissue sections were digested with chondroitinase ABC to create the antigenic determinant on the chondroitin sulfate proteoglycan molecule. Normal CNS tissue showed a positive immunohistochemical staining both in white and gray matter, sparing the cytoplasm of glial and neuronal cells. Differentiated astrocytomas presented the same pattern as the normal CNS. Anaplastic astrocytomas and glioblastomas showed progressive reduction of parenchymal positivity as anaplasia increased. These data suggest that chondroitin sulfate is a character expressed by differentiated CNS cells and that it is lost with dedifferentiation. Vascular structures presented positive material in the adventitia in all the oncotypes. A discontinuous positivity was observed in the basal membrane zone of the vessels.

Astrocytoma↗
PubMed1986

Immunohistochemical demonstration of vimentin in human cerebral tumors.

The distribution of vimentin (VIM) has been histochemically investigated in 53 cerebral tumors and compared in gliomas to that of glial fibrillary acidic protein (GFAP). In gliomas VIM is less positive than GFAP, but shows the same distribution. It cannot be considered as indicating immaturity of glial tumor cells. VIM is also positive in glial processes of cerebellar pilocytic astrocytomas, in Schwann cells of neurinomas and in endothelial cells of all oncotypes. In medulloblastomas, VIM decorates reactive glia cells. A diffuse positive reaction has been observed in meningiomas. In hemangioblastomas, besides intervascular and endothelial cells, groups of polygonal cells are intensely positive for both VIM and GFAP. The interpretation of VIM in cerebral tumors is largely based on the distribution patterns of this intermediate filament in the developing CNS of rodents.

Astrocytoma↗
PubMed1986

Glycosaminoglycan changes in human gliomas. A biochemical study.

Glycosaminoglycans (GAGs) were isolated, separated by electrophoresis and quantified in 36 neurosurgical specimens of human gliomas and in 8 samples of normal white and gray matter. Gliomas of various degrees of malignancy exhibited different GAG patterns. Total GAG concentration was three times higher in low grade gliomas than in normal white matter. The mean percentage of single GAG classes was usually similar in both tissues, although in certain tumor samples a higher percentage of hyaluronate was found. GAG patterns in anaplastic astrocytomas, however, more closely resembled normal white and gray matter, both quantitatively and qualitatively. Glioblastomas, on the other hand, showed high GAG concentrations, in particular of heparan sulfate and dermatan sulfate. This finding could be secondary to the abundant vessels and mesodermal material associated with this oncotype. The hyaluronate/sulfated GAGs ratio was lower in oligodendrogliomas than in low grade astrocytomas. This biochemical feature may be correlated with the alcianophilia found in the honey-comb degeneration of oligodendrogliomas. The significance of these findings as they relate to tumor histology and biology have been discussed.

Brain Neoplasms↗
PubMed1986

Prevalence of hereditary ataxias and paraplegias in the province of Torino, Italy.

A descriptive epidemiological survey of hereditary ataxias and spastic paraplegias was conducted in the province of Torino, Italy (2,327 996 inhabitants). On prevalence day (31 December 1982) 142 patients were alive. Total prevalence was 6.1 cases/100,000 inhabitants (95% confidence limits = 5.1-7.0). The prevalence rate was 2.6 for recessive or sporadic juvenile ataxias, 1.3 for spastic paraplegias, 1.2 for autosomal dominant cerebellar ataxias, and 1.1 for late onset cerebellar ataxias. The prevalence of hereditary ataxias is similar in our province to that recorded in other populations, but hereditary spastic paraplegias are less frequent than in other populations.

Adult↗
PubMed1986

Quantitative analysis of quadriceps muscle biopsy. Results in 7 definite and 45 possible carriers of Duchenne muscular dystrophy.

Quadriceps muscle biopsy was performed in 7 definite and 45 possible carriers of Duchenne muscular dystrophy. Unequivocal morphological changes were observed in 8 women; all but one of them were already detected as carriers by increased serum CK. Histometric analysis of muscle biopsy was performed on two fibre types (type 1 and type 2) in all 52 women; in 38 of them the two subgroups of type 2 fibres (type 2a and type 2b) were also quantified. Results of histometric analysis were matched with control values obtained from 30 healthy females in the same age as the carriers (20-50 yr). Histometric analysis on two fibre types detected a percentage of carriers (27%) much lower than that detected by serum CK determination (44%). The detection rate of combined serum CK determination and histometric analysis of muscle biopsy was: 100% in definite carriers, 65% in mothers possible carriers, 38% in sisters and 25% in the group of cousins and aunts. The histometric parameters most frequently altered were atrophy factor and variability coefficient of mean diameter. Histometric analysis carried out on three fibre types in 38 women detected 2 more carriers showing atrophy of type 2b fibres. The results indicate that quantitative analysis of muscle biopsy may be used to detect some possible carriers with normal serum CK. However, an adequate number of controls is mandatory; in fact the detection rate of histometric analysis of muscle biopsy decreased by increasing the number of controls, resulting much lower than previously reported.

Adult↗
PubMed1986

Clinical-anatomic study of a family with bulbo-spinal muscular atrophy in adults.

Four cases are presented, with bulbo-spinal muscular atrophy characterised by adult onset and rapid evolution. They belong to a family in which the type of inheritance is probably dominant. Two cases were studied histologically. The most striking feature was the disappearance of neurons in the lower motor nuclei of medulla and of the spinal anterior horns. An electron microscopic study was carried out in one case. Accumulation of neurofilaments was a general characteristic, in addition to the picture of different sized spheroids. The clinical-pathological relationship is discussed.

Adult↗
PubMed1986

Immunohistochemistry in neuro-oncology.

The technical modalities of the immunohistochemical demonstration of antigens of neuroectodermal differentiation and of mesenchymal nature in neural tissue are discussed. On the main antigens (S-100 protein, GFAP, Vimentin, Neuronal specific Enolase, neurofilaments, myelin basic protein, carboanhydrase C, FVIII/RAg, laminin, fibronectin) the most important findings are described and critically considered. They are interpreted in the light of the present knowledge on the problems of differentiation of the oncotypes and on particular aspects of bio-pathology of brain tumors.

Astrocytes↗
PubMed1985

1-Naphthol basic dye (1-NBD). An alternative to diaminobenzidine (DAB) in immunoperoxidase techniques.

The usefulness of 1-naphthol as substrate for horseradish peroxidase (HRP) in immunohistochemistry was studied using the peroxidase-antiperoxidase (PAP) and avidin-biotin-complex (ABC) methods in the demonstration of glial fibrillary acidic protein (GFAP), vimentin, carbonic anhydrase C (CA.C), and factor VIII-related antigen (FVIII/RAg) in central nervous tissue and cerebral tumors. In the presence of ammonium carbonate, 1-naphthol is oxidized by HRP and hydrogen peroxide, producing a fine gray-violet precipitate. The oxidation product of 1-naphthol proved capable of binding a great number of basic dyes. For each stain the final reaction product had a characteristic color that was different from the spontaneous color of the dye and from the color displayed by nuclei. The final color obtained with this procedure was alcohol resistant and could be mounted in solvent-based mounting media. The results obtained with the 1-naphthol basic dye (1-NBD) method were compared with those obtained using the diaminobenzidine (DAB) reaction in the demonstration of GFAP-positive astrocytes. The DAB reaction produced a more intense staining but also a coarser precipitate than the 1-NBD reaction. The 1-NBD procedure showed more morphological detail of fine structures and did not obscure nuclei and mitosis. The very low toxicity of 1-naphthol compared with DAB (a suspected carcinogen) is an important advantage of the 1-NBD method, as is its high specificity and sensitivity.

3,3'-Diaminobenzidine↗
PubMed1985

The distribution of laminin in human brain tumors: an immunohistochemical study.

The immunohistochemical distribution of laminin in 70 cases of primary and secondary brain tumors has been studied. The sections were fixed in Carnoy, embedded in paraffin, and treated with collagenase before applying the specific immune serum. In normal neural tissue and in gliomas, the distribution of laminin overlaps with that of basement membrane, as is known from observations on ultrastructure in the literature. The overlapping was observed also in neurinomas, papillomas of the choroid plexus, ependymomas, and meningiomas. Problems arise in the interpretation of the results in the other oncotypes. In hemangiopericytomas and hemangioblastomas, laminin demonstrates a basement membrane around the vessels only; it is absent around stromal cells. In desmoplastic medulloblastomas, laminin forms a network among the tumor cells. In primary lymphomas, concentric rings of laminin are evidenced around some vessels. In discussing the results, the ultrastructural distribution of basement membranes is taken into account.

Basement Membrane↗