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Biomedical subjects

K Schmidt

Publications and source records attributed to K Schmidt.

At least 595 records · Page 33Linked to original sources
PubMed1975

[Simplification of the dinitrophenylhydrazine method for the photometric determination of ascorbic acid and dehydroascorbic acid in fruit juices. I. Application to juice of black current (author's transl)].

The photometric determination of ascorbic acid and dehydroascorbic acid by preparing the 2,4-dinitrophenylhydrazone derivative of dehydroascorbic acid and purifying it by thinlayerchromatography was simplified and adapted to the microliter system of Eppendorf Gerätebau, Hamburg, Germany. Using this method with juice of black current, quite reproducible results for vitamin C contents were obtained. Compared with the method of the International Federation of Fruit Juice Producers (titration with 2,6-dichlorphenolindophenol) the contents of vitamin C found with nine different commercial juices of black current were lower from 13 to 30%.

Ascorbic Acid↗
PubMed1975

Pathologic-anatomical findings and cerebral localization in stereotactic treatment of extrapyramidal motor disturbances in multiple sclerosis.

Two postmortem case of multiple sclerosis treated by sterotactic operations for the intention shaking of limbs, trunk, and head, and for the action myoclonus are analyzed to determine the location of the substrate of myoclonic and ballistic movements, the location of the coagulations for relief of these movements, and whether fresh demyelinating foci are elicited by intracerebral interventions. In the first case of a clinically typical multiple sclerosis, the foci responsible for the severe action myoclonus and intention ataxia of the trunk are demyelinations in the right and left red nucleus resulting in nerve cell damage and loss and an almost complete destruction of myelinated fibers. The restricted foci in the white matter of the cerebellum which do not involve the cerebellar nuclei are not extensive enough or old enough to be the cause of the action myoclonus but may, perhaps, sustain the pathogenesis. - In the second case of cerebral palsy and combined multiple sclerosis (detected post mortem), the combination of the severe damage of putamen and caudate nucleus by status marmoratus and the extensive nerve cell and fiber damage due to demyelinating foci in the substantia nigra are probably the substrate of the jactitation and intention myoclonus of the left limbs. The stereotactic coagulation of the dentatothalamic and pallidothalamic fibers in the base of V. o.p. and V.o.a. at the point where they pass through the zona incerta (location confirmed post mortem) resulted in a nearly complete relief of hyperkinetic movements. In the first case, fresh demyelinating foci are present in both hemispheres with stereotactic interventions; these foci are located, amongother places, around the coagulation and the electrode track. In the second case, post mortem serial brain sections demonstrate that stereotactic operations even in subacute multiple sclerosis can be carried out without eliciting any exacerbation of demyelination foci. Therefore, the danger exists that stereotactic intervention in cases of multiple sclerosis may precipitate fresh demyelinating foci. As our clinical experience [Riechert and Richter, 1972a, b] indicates, however, this occurred in markedly less than 10% of the cases.

Adult↗
PubMed1975

Stereotactic treatment of action myoclonus in a case of combined status marmoratus and multiple sclerosis. A contribution to the pathophysiology of basal ganglia with multiple lesions in both the striatum and the substantia nigra.

A patent, who suffered from nonprogressive athetotic-myoclonic hyperkinesia of the left arm and spastic paresis of the underdeveloped left leg since early childhood, experienced a febrile episode at the age of 23, after which a weakness and ataxia of the right limbs with frequent falling persisted; at the age of 28, he developed a right-sided rigidity, tremor at rest and mask-like face as sequelae of encephalitis disseminata exacerbations. The violent intention myoclonus of the left side of the body could be abolished by stereotactic coagulation in the V.o.p and V.o.a and zona incerta until death 11 days later. The athetotic myoclonic hyperkinesia is the consequence of a left-sided severe status marmoratus of the right putamen with extensive loss of nerve cells and shrinkage. The additional nerve cell loss in the right substantia nigra due to demyelinating encephalitic foci did not produce Parkinson symptoms, because these require a normal striatum. This loss did, however, exaggerate the original hyperkinesia to a violent intention myoclonus, which was abolished by interruption of denatatothalamic afferents to the V.o.p nucleus and of pallidothalamic afferents to the V.o.a nucleus. The Parkinson syndrome of the right side is due to demyelinating foci of different ages. The Parkinson symptoms were manifest on the right side, because the left status marmoratus did not severely reduce the striatal nerve cells. In this case, there is no indication that the introduction of the stereotactic electrode has precipitated new demyelinating foci.

Adult↗
PubMed1975

[Peroral intestinal mucosal biopsies. Comparative studies on the histological and the dissecting microscope findings (author's transl)].

From 1969 to 1973 171 peroral intestinal biopsies were carried out at the Children's Hospital Tübingen using the Crosby-Kugler capsule and the Watson intestinal biopsy capsule of paediatric size. The dissecting microscope findings were compared with the histological findings. The former correlated in stage II and III, according to the Shmerling scale, with the histological findings. Findings under the dissecting microscope, stage I, did not correlate in all cases with the histological findings. It is supposed that this results from either an inaccurate orientation or from inadequate sectioning. The plane of sectioning must be parallel to the villi. If the plane of sectioning is not parallel to the villi, the slender villi under the dissecting microscope look like plump villi when examined histologically. It is supposed that this results in a greater number of plump villi and a smaller number of slender villi in the histological findings compared with the dissecting microscope findings. The correspondence of slender villi examined under the dissecting microscope and those which are histologically examined in about 25 to 100%.

Biopsy, Needle↗
PubMed1975

[Hereditary deficiency of isomaltase and saccharase responsible for a malabsorption syndrone (author's transl)].

Among 135 infants and children with a supposed malabsorption syndrome, a deficiency of isomaltase-saccharase of the duodenal mucosa was detected in 5 cases by measuring the disaccharidases directly in the mucosa homogenate. In one instance a deficiency of lactase was found in addition. In all patients the villi were of normal length, with an increased cell infiltration of the stroma detected in two cases. The loading tests with xylose-sucrose yielded a diminuished rise in the blood glucose level. Three of the patients were dwarfish, but only one showed an increased growth after the reduction of sucrose in the supplied diet. As a result of adaptation difficulties in the change of diet, one patient had to be treated with an additional saccharase substitution.

Adolescent↗
PubMed1975

[The difficulties to diagnose a clinical important defect of disaccharidases (author's transl)].

Duodenal mucosa of 100 infants and children was histologically investigated and the activities of dissaccharidases in the mucosa homogenate were determined. In addition, a combined xylose-lactose loading test was carried out and the behaviour of the stools under the test conditions was observed. The results were compared with regard to the clinical importance of an enzyme defect. The rise of xylose in blood gives no evidence for a defect of disaccharidases in the mucosa. The determination of the glucose maximum after a loading test with disaccharides seems rather to lead to false-normal results. The possiblity of a false-pathological interpretation by an exclusive determination of enzymes must be prevented by further gastroenterological examinations.

Adolescent↗
PubMed1975

[Disaccharidases of the small intestine mucosa in infants and children. "Normal values", log normal distribution and age dependence].

In 63 infants and children with a histological normal mucosa of the duodenum, without an isolated defect of enzyme and with a normal increase of xylose and glucose in serum after a combined xylose-lactose loading test the activities of disaccharidases were log normal distributed. The asymmetric distributions were transformed into symmetric ones and the geometric mean (x) as well as the range (+/- 2 s) of maltase, saccharase, isomaltase, lactase and trehalase were calculated. Only the activity of lactase shows a significant dependency on age. In the first year of age the lower limit (x -- 2 s) of this enzyme is much higher than later.

Age Factors↗