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D Schulz

Publications and source records attributed to D Schulz.

At least 73 records · Page 4Linked to original sources

[Anatomical structures, physiology and pathophysiology of cerebrospinal fluid metabolism; a review for an understanding of cerebrospinal fluid findings].

The very different macroscopic and microscopic details of the structures involved in production and reabsorption of cerebrospinal fluid in the different parts of the central nervous system are causing confusing laboratory findings in cerebrospinal fluids, the ingredients of which change even under normal condition in these different parts. Moreover the chemical ingredients of cerebrospinal fluid differ especially from the normal situation during some diseases of the central nervous system. Although we can be sure that there is much more diagnostic information in cerebrospinal fluid, we mainly prefer certain standard methods today, as there are cell counts and measuring of the protein concentration, as diagnostic parameters. Their unspecific changes during several pathologic states do not yet allow to point out the exact localization of the disease, nor can they contribute in every case in finding the cause of the disease. Therefore other and more specific diagnostic laboratory methods are to be developed, which will make possible more precise statements about the nature and the localization of central nervous system diseases.

Absorption↗

[Development and current possibilities of cerebrospinal fluid diagnosis in the routine laboratory. 2. Studies on protein composition].

In the 1st part of this paper (Schulz et al. 1979) a survey was given of the cytological and the chemical procedures at present available for cerebrospinal fluid diagnostics. The 2nd part describes different laboratory methods to separate the protein mixture of cerebrospinal fluid into protein fractions or single proteins. These surveys intend both an improvement of the quality and a unification of laboratory methods regarding diagnostic examinations of cerebrospinal fluid.

Electrophoresis↗

[Development and current possibilities of cerebrospinal fluid diagnosis in the routine laboratory. 1. Cytological and microbiological studies and methods of chemical analysis].

Although there are many precisely working procedures for diagnostic examinations of cerebrospinal fluid, very often methods are used which do not fulfill conditions of adequate quality. The aim of this survey of several cytological and chemical methods, of their development during the past 80 years, of their advantages or disadvantages, and of the various difficulties is to contribute to a discussion on improvement of quality and on unification of laboratory methods regarding diagnostic examinations of cerebrospinal fluid. Several procedures to separate protein fractions or single proteins in cerebrospinal fluid will be discussed in the second part of this paper.

Central Nervous System Diseases↗

[Glucose-6-phosphate dehydrogenase deficiency of the mediterranean type B minus. 2. Etiological basis for severe hyperbilirubinemia in the newborn].

After having described in detail the pathophysiology, symptomatology, X-chromosomal inheritance and some laboratory methods in detecting G-6-PD-deficiency by demonstrating a case of favism (Schulz et al. 1977), the authors now discuss the particularities of the enzyme deficiency in the newborn. These are complicated by additional physiological and transient deficiency of the enzymes catalase, NAD-diaphorase, glutathione peroxidase, and glucuronyl transferase. Several chemical substances, acidosis, hypoxia, hypoglycemia, and immaturity may cause a severe hyperbilirubinemia in G-6-PD-deficient newborns. The development of a kern-icterus in these cases may be prevented by early exchange transfusion. From clinical findings and some observations in different regions of Greece an additional factor influencing the liver function has been postulated which favors the development of hyperbilirubinemias in G-6-PD-deficient newborns. The nature of this possible factor is discussed. The authors emphasize the necessity of screening for G-6-PD-deficiency during pregnancy in families of mediterranian descent.

Cephalexin↗

[Changes in liver haemodynamics after mesenterico-caval dacron prosthesis anastomosis ("H-shunt") in portal hypertension (author's transl)].

In fourteen patients with portal hypertension and bleeding from oesophageal varices, mesentericocaval anastomoses using a dacron-velour prosthesis ("H-shunt") were carried out. Evaluation of the haemodynamics showed: 1. Comparison of 13 pre- and post-operative angiograms showed an haemodynamicically effective shunt in 12 and a stenosed shunt in one. 2. The aim of relieving the portal circulation while maintaining antegrade portal flow was achieved in six patients. 3. In six patients, the portal vein was not seen in a splenic or mesenteric portogram despite an open shunt. Functionally, this corresponds to a porto-caval anastomosis. 4. Pressure reduction in the portal circulation can be so marked as to obtain retrograde portal flow from the hepatic artery. 5. If the portal blood flow through the liver disappears, the hepatic artery may obtain additional flow from the superior mesenteric artery (reversed flow in the gastroduodenal artery). 6. Increased arterial flow to the liver is made possible by a reduction in intrahepatic resistance. The role of collaterals, either arterio-portal shunts or shunts between the sinusoids, is discussed. 7. The hepato-fugal collateral circulation was reversed in twelve patients.

Adult↗

Analysis of the distribution of spindle microtubules in the diatom Fragilaria.

The spindle of the colonial diatom Fragilaria contains two distinct sets of spindle microtubules (MTs): (a) MTs comprising the central spindle, which is composed of two half-spindles interdigitated to form a region of "overlap"; (b) MTs which radiate laterally from the poles. The central spindles from 28 cells are reconstructed by tracking each MT of the central spindle through consecutive serial sections. Because the colonies of Fragilaria are flat ribbons of contiguous cells (clones), it is possible, by using single ribbons of cells, to compare reconstructed spindles at different mitotic stages with minimal intercellular variability. From these reconstructions we have determined: (a) the changes in distribution of MTs along the spindle during mitosis; (b) the change in the total number of MTs during mitosis; (c) the length of each MT (measured by the number of sections each traverses) at different mitotic stages; (d) the frequency of different classes of MTs (i.e., free, continuous, etc.); (e) the spatial arrangement of MTs from opposite poles in the overlap; (f) the approximate number of MTs, separate from the central spindle, which radiate from each spindle pole. From longitudinal sections of the central spindle, the lengths of the whole spindle, half-spindle, and overlap were measured from 80 cells at different mitotic stages. Numerous sources of error may create inaccuracies in these measurements; these problems are discussed. The central spindle at prophase consists predominantly of continuous MTs (pole to pole). Between late prophase and prometaphase, spindle length increases, and the spindle is transformed into two half-spindles (mainly polar MTs) interdigitated to form the overlap. At late anaphase-telophase, the overlap decreases concurrent with spindle elongation. Our interpretation is that the MTs of the central spindle slide past one another at both late prophase and late anaphase. These changes in MT distribution have the effect of elongating the spindle and are not involved in the poleward movement of the chromosomes. Some aspects of tracking spindle MTs, the interaction of MTs in the overlap, formation of the prophase spindle, and our interpretation of rearrangements of MTs, are discussed.

Cell Cycle↗

[Fractionation of human erythrocytes according to their sedimentation behaviour caused by gravity. II. Application for the differential diagnosis of erythroblastosis caused by incompatibility in the abo blood group system (author's transl)].

In contrast to Rh-erythroblastosis the diagnosis of A/B0-erythroblastosis by means of serological methods is often impossible. Further biochemical investigations, the demonstration of elevated erythrocyte sedimentation rates in polyvinylpyrrolidone and of typical microsphaerocytes in blood smears can support the diagnosis. Using a modified method by Danon et al. the authors demonstrate an additional population of heavy erythrocytes in the blood of patients suffering from A/B0-erythroblastosis, the relative amount of which correlates with the severity of the disease. The fast method seems to permit prognostic predictions in cord blood.

ABO Blood-Group System↗

[Fractionation of human erythrocytes according to their sedimentation behaviour caused by gravity. I. Methodical Investigations (author's transl)].

The usefulnes of a method to differentiate erythrocytes according to their specific gravity introduced by Danon et al. is demonstrated by using blood samples of healthy children and of others with different haematological diseases. Several conditions affecting the results are investigated. For clinical purposes the simple method is only applicable, if the results are presented as intervals of density.

Adolescent↗

[Results of transjugular antegrade cholangiography and retrograde portography (author's transl)].

Via the jugular approach to the liver diagnosis of the liver could be extended by transjugular cholangiography, liver biopsy and retrograde portography. Transjugular cholangiography makes possible an antegrade picture of the bile ducts - particularly when conventional techniques or retrograde measures fail. 85% of blocked bile ducts were recognized. Transjugular liver biopsy complements cholangiography. Tissue can be removed from right and left lobes of the liver. Retrograde portography makes possible assessment of hemodynamics of the liver in portal hypertension before and after shunt operations. Isolated pictures of portal circulation in the right or left lobes permits clear allocation of tumorous or parasitical disease in the respective parts of the liver. This is of special importance for surgery of the liver, a precondition of hemihepatectomy.

Adult↗

[Trans-jugular retrograde portography. Preliminary communication].

Retrograde portography is carried out through a trans-jugular route. Contrary to previously available techniques of trans-juglar portography, the method does not inflict any trauma on the parenchyma or vessels. Demonstration of the portal system is achied by reserved flow through the liver sinusoids. Together with arterial hepatography and indirect splenic and mesenteric portography, the method provides additional information in various forms of pre-, intra- and post-hepatic block without submitting the patient to any additional risk.

Aged↗

[How reliable are assays with the ictometer? Comparative studies with direct measurement of billirubin and a diazo technique (author's transl)].

Comparison of measurements of a diazo technique with those of a direct assessment of bilirubin with the photo-ictometer type II (Hirtz & Co., Cologne). Comparative analysis of total bilirubin-concentration in 172 non-hemolytic sera of neonates and in dilution series with and without contamination by hemoglobin and/or lipid-suspension gave the following results and conclusions drawn from them: 1. In non-contaminated sera the relation between the two techniques is linear, well correlated, parallel and with little divergence. 2. In contrast to the ictometer the diazo technique used underrates the bilirubin content in hemolytic sera. 3. In contrast to the diazo technique the ictometer underrates the bilirubin content in strongly turbid sera. 4. The precision of the ictometer is superior in series and from day to day to the already good precision of the diazo technique. 5. The standard built- in after calibration has to be checked daily and adjusted during the first working hour of the ictometer on several occasions. 6. In order to aboid major systematic faults each apparatus should be compared with a safely calibrated technique. 7. The very simple and rapidly serviced apparatus is suitable for the assay of total bilirubin in sera of the newborn. For older neonates and after exchanges transfusions the results should not be trusted.

Age Factors↗

[Catheter embolisation of the splenic artery as treatment for acute bleeding from varices (author's transl)].

Embolisation of the splenic artery with fibrin foam, in order to stop acute bleeding from varices, was carried out in two patients. This was performed immediately after diagnostic arterial indirect demonstration of the portal vein; by this method it is possible to achieve at least a temporary cessation of bleeding from oesophageal or gastric varices. The procedure is indicated in desparate situations, if intubation has been unsuccessful or has had to be discontinued, when endoscopic sclerosis is contra-indicated or when an emergency shunt cannot be carried out because of poor liver function or the general condition of the patient. Permanent results cannot be expected and recurrence of bleeding cannot be avoided. The use of splenic embolisation depends on stopping the acute bleeding in order to obtain an interval during which liver function can be improved so that a decompressing shunt operation becomes possible subsequently.

Acute Disease↗

[Cancer arising on cirrhosis of regenerative node (author's transl)].

12 patients with cancer arising from a cirrhosis of the liver and 8 patients with regenerative nodes in a cirrhotic liver have been examined with scintigraphy, serial scintigraphy, angiography and biopsy. The results show that defects in the parenchyma of the liver can be shown with relative certainty using conventional scintigraphy with radiocolloids. But nothing can be said about their nature. Because of the simplicity of this technique and the minor claims on the patient scintigraphy should be the first diagnostic step. If angiography is contra-indicated serial scintigraphy may further elucidate the effects. When, however, angiography can be done, it will offer the best chance of differentiating between cancer and regenerative nodes on the basis of cirrhosis.

Angiography↗