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Biomedical subjects

T Mannen

Publications and source records attributed to T Mannen.

At least 109 records · Page 6Linked to original sources

Neuropathological changes of the brain in myotonic dystrophy--some new observations.

Brain autopsy materials from 2 patients with myotonic dystrophy (MyD) were studied. The results obtained in these 2 cases were quite similar. Besides thalamic inclusion bodies and minor abnormalities in gyral architecture with a disordered cortical cellular arrangement, some new observations have been made. First, no more than one intracytoplasmic inclusion body per cell was present in the cerebral cortex, the thalamus, the caudate nucleus and the putamen; this inclusion body was oval or elongated with smooth, sharply defined contours and was usually located at the periphery of the cell. Second, irregular intracytoplasmic inclusion bodies, often multiple and not surrounded by a halo, were found at the periphery or within accumulations of neuromelanin granules in the pigmented cells of the substantia nigra. All the bodies described above stained highly eosinophilic with hematoxylin-eosin and the ultrastructure of the bodies in the thalamus and the substantia nigra was almost the same; these bodies were composed of stacks of alternating parallel, light and dark rectilinear profiles oriented perpendicularly to the longitudinal axis of the bodies. Third, Marinesco bodies were observed with a very high frequency in the pigmented cells of the substantia nigra.

Aged↗

Myopathology of hypothyroid myopathy. Some new observations.

Eight muscle biopsies (3 from the left biceps, 3 from the left gastrocnemius, and 2 from the left quadriceps) of patients with hypothyroid myopathy were studied in the light of the previous literature. Some new observations have been made. First, the percentage of type II fibres is higher than that of type I fibres in all but 1 cases before treatment. Second, 5 of 8 cases before treatment disclosed 'core-like' structures, readily recognized with oxidative enzyme preparations in eccentric positions or in the periphery of type I fibres. They were reactive with myofibrillar adenosine triphosphatase (ATPase) activity and periodic acid-Schiff(PAS) staining, whereas with hematoxylineosin (HE) and modified Gomori trichrome the regions were more strongly reactive than the rest of the fibre. When examined by electron microscopy, within the 'core-like' structures of affected fibres, the A, I, and Z banding pattern was markedly disrupted. These structures disappeared after treatment with L-thyroxine. Third, none of the cases with Hoffmann's syndrome showed individual muscle fibre hypertrophy. Further study of these findings may yield information on clarifying the characteristics of muscle pathology of hypothyroid myopathy.

Aged↗

"Ragged-red" fibres in myotonic dystrophy.

Twenty-five muscle biopsies (18 from the left biceps and 7 from the left quadriceps) of 25 patients suffering from myotonic dystrophy (MyD) were studied, 13 of which showed "ragged-red" fibres (RRFs); all the RRFs, which were type I fibres, were found in biceps muscles, while none of the quadriceps muscles showed RRFs. The incidence of RRFs varied from 0.5% to 20.0% (average 4.2%). On electron microscopy, RRFs contained enlarged mitochondria, usually in subsarcolemmal clusters, including dense granular matrix materials, concentrically whired membranous cristae, and paracrystalline inclusions, consistent with those of previously reported cases of mitochondrial myopathy, suggesting that RRFs observed in biopsies from patients with MyD are due to abnormal mitochondria. The biopsy findings indicative of MyD including pyknotic nuclear clumps, moth-eaten fibres, ring fibres, type I fibre atrophy, and type I fibre predominance, were much more common findings in biceps muscles than quadriceps muscles, and in biopsies with RRFs than those without RRFs. From our observations, it is possible that RRFs in biopsied muscles from patients with MyD are not incidental observations but are intimately associated with the pathogenesis of this disorder, and that RRFs may be a special form of pathological reaction in which accumulation of abnormal mitochondria occurs.

Adolescent↗

Amyotrophic lateral sclerosis: histologic, histochemical, and ultrastructural abnormalities of skin.

We studied the reticular dermis in patients with amyotrophic lateral sclerosis (ALS) and controls with or without neurologic diseases. By light microscopy, collagen bundles in ALS dermis were reduced in amount and more loosely woven than in controls. Electronmicroscopy revealed a significant negative correlation between duration of illness and the diameter of collagen fibrils in patients with ALS. There was also a marked increase of amorphous material positive for ruthenium red in the ground substance. These findings were not observed in controls.

Adult↗