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J Fischer

Publications and source records attributed to J Fischer.

At least 397 records · Page 22Linked to original sources
PubMed1986

Argyria: microanalytic-morphologic correlation using paraffin-embedded tissue.

Scanning electron microscopes, which have energy dispersive spectroscopy (x-ray microanalysis) capability, can provide accurate identification of the composition of inorganic deposits in tissue. We report a case of florid argyria in which the same deparaffinized 4-micron sections were sequentially examined by light microscopy, scanning electron microscopy, backscattered electron imaging, and x-ray microanalysis to confirm the clinical impression of argyria. We recommend the use of x-ray microanalysis of paraffin-embedded tissue as a simple, rapid and inexpensive means of precise identification of inorganic deposits of heavy elements in tissue sections.

Administration, Intranasal↗
PubMed1986

Production and characterization of mouse monoclonal antibodies to allergenic epitopes on LolpI (Rye I).

This study describes the production and characterization of mouse monoclonal antibodies (Mab) to LolpI (Rye I), the major allergen of rye-grass pollen. Hybridoma cell lines were screened for the secretion of Mab, the binding of which to labelled LolpI could be inhibited by pooled human sera containing IgE and IgG anti-LolpI antibodies. Twenty monoclonal hybridoma cell lines were expanded, and their product was purified and characterized. Each Mab bound to LolpI but not to unrelated antigens. Cross-inhibition studies allowed the grouping of these 20 Mab into five families differing by their epitope specificity. One representative Mab of each family was tested for its ability to inhibit human IgE/IgG anti-Lolp-I from 15 allergic donors as well as for its inhibition by affinity-purified anti-LolpI antibodies isolated from 14 donors. The results indicated that each family of Mab was specific for an epitope that was identical or close to that recognized by some human anti-LolpI antibodies. It is further shown that human IgE/IgG anti-LolpI are heterogeneous with some patients reacting preferentially with one or two epitopes defined by the Mab LolpI, and others reacting with epitopes different from those identified by the Mab LolpI.

Allergens↗
PubMed1986

[Hepatitis B risk in dental personnel].

Dependent on the profession, medical personal is at different risk of hepatitis B infection. 505 staff members of 48 Berlin dental clinics were investigated for hepatitis B virus markers and demonstrated a significantly lower prevalence of HBsAg and its antibody than other hospital personal: anti-HBs positivity (EIA) was found in only 5.5 per cent of them (dental technicians: 1.6%, dental assistants: 3.8%, dentists: 8.0%). We conclude that in the GDR dental staff is not at higher risk of hepatitis B infection than other non-risk medical personal. Legal aspects of insurance and measures for hygienic prevention in dental practice are discussed.

Adult↗
PubMed1985

[Multidisciplinary study of the prolonged treatment of involution osteoporosis using sodium fluoride with calcium, phosphate and vitamin D].

A multidisciplinary study on the prolonged treatment of involution osteoporosis with fluoride was performed on a homogeneous population of 31 women aged 51 to 75 years (mean 64 years). The selection criteria were the following: significant backache, vertebral compression fractures on X-rays, bone biopsy evidence of osteoporosis, and absence of other risk factors after a complete workup. The patients were treated for a period of 3 to 6 years (mean 4 years) with daily doses of 30 mg (10 mg 3 times) fluorides ion associated during the last 3 years with 500 mg calcium twice daily, 750 mg phosphate and 1000 units vitamin D daily. The study demonstrated a favourable effect of the treatment on the backache and that it was well tolerated in the majority of cases, the side effects being intermittent osteo-articular pains of the lower extremities due to the fluoride in 9 patients, and gastric intolerance to the phosphate in 7. X-ray follow-up showed slowing of the vertebral compressions after the first year of treatment, but no effect on fractures of the extremities. There was no evidence of alterations in parameters of mineral and bone metabolism, and in endocrine, hepatic, renal or hematological assays. Histomorphometric and biophysical examination of biopsies indicated that, although there was no significant increase in the quantity of mineralized bone under the treatment, there was a very significant improvement in the crystallinity of the mineral substance, thus enhancing the quality of the bone tissue and its resistance to pressure. This study is the first in which a catamnesis of the patients was undertaken, 28 of them having received a clinical and radiological examination 2 years after the end of therapy: a favourable evolution was observed in most of the cases, both in those patients treated for a period of 3 years and in those whose treatment had lasted for a longer period.

Aged↗
PubMed1985

Demonstration of regional blood-brain barrier permeability in human brain.

The brain of a 78-year-old woman with argyria was examined at autopsy. Silver nitrate deposition was observed in circumventricular organs (CVO) and in the paraventricular and supraoptic nuclei of the hypothalamus. These findings parallel animal experiments of other investigators and are the best demonstration so far of regional absence of the blood-brain barrier in humans. These observations demonstrate similarities between humans and other mammals of CVO anatomy, permeability to blood-borne agents, and perhaps neural connections between CVOs and magnocellular nuclei.

Aged↗
PubMed1985

Gliosarcomas: histological, immunohistochemical, ultrastructural, and tissue culture studies.

Thirty-nine cases of gliosarcomas, two initiating as fibrosarcomas, 25 as mixed gliomas and sarcomas, and 12 as anaplastic gliomas with secondary sarcomas, were studied by light microscopy, immunohistochemistry, using GFAP, factor VIII/RAg, and Ulex europaeus I agglutinin (UEA I), electron microscopy and tissue culture. GFAP was found variably positive in the glial areas; F VIII/RAg and UEA I, markers of both normal and neoplastic endothelial cells and their derivatives, were found in vessels of both gliomatous and sarcomatous parts of GS, less intensive in hyperplastic glomeruloid structures and, with decreasing intensity, in adjacent fibrosarcomatous areas, while UEA I, giving stronger reaction than F VIII/RAg, was occasionally demonstrated in sarcomatous cells. In vitro studies confirmed previous data of a separate growth of glial and mesenchymal cells with a divergent migratory speed. Electron microscopy demonstrated the frequent close admixture of glial and mesenchymal tumor cells, which showed the feature of either fibrosarcoma or angiosarcoma. The frequent resemblance of the latter with endothelial cells was supported by the occasional demonstration of Weibel-Palade-like bodies in both vascular endothelial and adjacent sarcomatous cells. These observations confirm the hypothesis that at least part of the sarcomatous components in many GS originate from vascular endothelial proliferation and obviously represent the final stage of a process starting with the endothelial hyperplasia in anaplastic gliomas.

Adolescent↗
PubMed1985

[Instrumental esophageal perforation--its treatment and results].

The number of oesophagus perforations has increased considerably with the increase in endoscopic, diagnostic and therapeutic procedures. 46 instrumental oesophagus perforations have been observed between 1973 and 1984. The youngest patient was a 2-year-old girl with a benign oesophagus stenosis and the eldest was an 89-year-old man with a neoplasm of the cardia. The average age was 62 years. 26 patients were treated conservatively; 20 patients were treated surgically. In 2 cases the oesophagus was diverted at the cervical level and the cardia detached. 8 months later this was successfully reconstructed. 9 out of 43 patients died. In every case, the cause of death were cardio-pulmonal complications accompanying general sepsis.

Adolescent↗