[A new method for the clinical determination of urinary porphobilinogen and delta-aminolevulinic acid]

A new method has been developed for clinical determination of porphobilinogen and delta-aminolevulinic acid in urine. Compared with the method of Mauzerall and Granick, being the most commonly used method for clinical application, there is an essential reduction of work and needed time. During the flow of 0.5 ml urine on a 0.7 cm x 2 cm column of macroporous cation exchange resin in H+-form porphobilinogen and delta-aminolevulinic acid are bound to the resin. After rinsing the column with 3 ml N acetic acid and 1 ml H2O the bound hemprecursors were eluted with 5 ml buffer. Concentration of porphobilinogen and of the pyrrol, synthesized from delta-aminolevulinic acid by Knorr-reaction is measured photometrically at 546 nm after Ehrich-reaction. After a short-time regeneration of columns -- 5 ml buffer, 3 ml N acetic acid -- these columns can be reused at least 20 times.

Comparison of the effect of two groups of diuretics on renin secretion in the anaesthetized dog

1. The effects of two groups of diuretics on renin secretion have been compared in dogs anaesthetized with pentobarbital. 2. Frusemide, ethacrynic acid and bumetanide cause an immediate rise in renin secretion which is not inhibited either by DL-propranolol or by a bilateral ureterovenous anastomosis which prevents salt and water loss. 3. Clopamide, metolazone and indapamide do not cause an immediate rise in renin secretion. Renin hypersecretion is induced only 1 h after intravenous injection of these diuretics. 4. Renin secretion was studied for 6 h after frusemide injection: the immediate rise was followed by a later increase in renin secretion. This later rise was inhibited by propranolol and by ureterovenous anastomosis. 5. These results allow us to distinguish between a direct renal mechanism responsible for early renin hypersecretion, which appears to be connected with the action of the diuretic on the ascending limb of Henle's loop, and an indirect mechanism responsible for late renin hypersecretion, which appears to be connected with salt and water loss.

[Heavy metal content of tobacco products and tobacco smoke]

The authors determined by means of square-wave polarography the copper, lead, cadmium and zinc contents in the tobacco and smoke of cigarettes (16 brands), cigars (5 brands) and pipe tobacco (3 brands) and discuss their possible actions on the human organism. A comparison of the amount of heavy metals taken up by an average smoker (at most 20 cigarettes per day) with the MAC values adopted in the GDR conveys the impression that the loading with copper, lead and zinc is unimportant, whereas, according to the findings of other authors, the loading with cadmium is but seemingly insignificant.

[Infrared-spectroscopic studies of the carbonate apatite structure of dental hard tissues]

Samples of enamel, dentine and cementum were calcined at temperatures of 500 degrees C, 800 degrees C and 1000 degrees C. The infrared spectra recorded at these temperatures were evaluated quantitatively and qualitatively. With increasing temperature, the conversion of the primarily present carbonate apatite into hydroxyapatite increased. At 800 degrees C, a hydroxyapatite proportion of 83% was found. At that, the thermal treatment produced in the dentine an increase in the degree of crystallization from 62% to 100%.

Effects of apomorphine and of pimozide on renin secretion in the anaesthetized dog

This paper presents the results of a study of the receptors involved in renin hypersecretion induced by dopamine. Apomorphine induces renin hypersecretion without significantly modifying the renal blood flow. This renin hypersecretion is inhibited by haloperidol. However, pimozide, a selective dopaminolytic agent, is incapable of inhibiting the renin hypersecretion induced by dopamine. These results provide supplementary evidence for the existence of renal dopaminergic receptors which would appear to differ from the central dopaminergic receptors.

[Reduction of smoking hazards by Denicotea filter-cartridges (author's transl)]

In the present study the efficiency of Denicotea filter-cartridges is determined as indicated by change of heart rate, skin temperature, urinary nicotine-content and subjective symptoms. Compared with standard smoking effects the use of Denicotea filters produces smaller increases in heart rate and significant reductions of urinary nicotine-content. The majority of the probands no longer experienced side effects. Thus, the elimination of nicotine from smoke by Denicotea filters is effectively demonstrated. Because only a minority of smokers is actually willing to discontinue their habit, despite medical advice, the introduction of Denicotea filters presents itself as a useful alternative.

[New method of thrombocyte counting. Technic of electronic counting of low thrombocyte concentrations in peripheral blood]

Starting from recent studies of Balleisen (1972) and Schmidt et al. (1973) about automated counting of platelets an automated method has been developed for accurate platelet counting at very low platelet concentration of peripheral blood. The method can be summarized as follows: 0,1 ml anticoagulated venous blood (Na-EDTA or polystyrol tubes containing EDTA powder) or capillary blood from finger tips was diluted with 20 ml of a mixture of Isoton-Periston-(Bayer-)Na2-EDTA (22:2:1 vol.) in polystyrol tubes. After 5 min centrifugation at 85 g, using an angle head and decantation into a polystyrol tube, second centrifugation. Decantation in a Coulter glass and counting at aperture 8, attenuation 0.500 and theshold 6 respectively 70 using at 70 mikron capillary. Counts at threshold 70 (erythrocyte counts) were subtracted from counts at threshold 6 (platelets and erythrocytes); to calculate platelet counts/mm3 multiplication by factor 2 at undiluted venous or capillary blood. The mean variation coefficient of our method being 4,1%, counting of platelets is possible with the accuracy of other automated methods at normal platelet concentration. At very low platelet counts our method seems to be the most accurate laboratory method for platelet counting.

[Leptospirosis epidemic (L. grippothyphosa) in the Mainz area, concerning the pediatric age group (author's transl)]

31 children, presenting with rather uncharacteristic symptoms of an infectious disease and being referred to this clinic mostly because of lymphadenitis of the neck (81%) and/or signs of meningitis (45%), were seen within a period of only eight weeks and proved to suffer from Leptospirosis (L. grippotyphosa). The majority of the patients belonged to the age group of one to six years and lived in rural environs. Our observation is considered to relate to a Leptospirosis epidemic and suggests, as opposed to the general acceptance, a much higher incidence of Leptospirosis in this country and, moreover, in children.

Summer day camp for multihandicapped children

A six-week enriched sensorimotor, communication, and recreational summer day camp for twenty multihandicapped preschool children is described. The program, planned and supervised by therapists and mental retardation counselors, provided training for students who worked as camp counselors. Each counselor was assigned to work with one child and family and was responsible for assessing, establishing goals, designing appropriate programs, attending the child throughout the day, and relating to the family. The camp provided a trial for use of the Functional Skills Profile (FSP), an assessment battery designed by physical and occupational therapists to measure performance changes in low functioning, developmentally handicapped persons in order to determine the value of therapy programs. The camp is evaluated in terms of improvement in the children, the effectiveness of the student training, and parent satisfaction.

Differences between lymphoid cell populations of guinea pigs and mice as determined by the response to mitogens in vitro

The stimulation of guinea pig lymphocytes by phytohemagglutinin (PHA), concanavalin A (ConA), methanol-extracted residues of tubercle bacilli (MER), purified protein derivative of tubercle bacilli (PPD), dextran sulphate (DS) and E. coli lipopolysaccharide (LPS), was determined and compared with that of mouse lymphoid cells. The sources of lymphocytes tested were spleen, thymus, lymph nodes and bone marrow. The degree of activation of DNA synthesis by PHA and ConA was higher in guinea pig thymocytes and lymph node cells than in corresponding sources of mouse lymphocytes. The optimum degree of stimulation by PHA and ConA was approximately the same in guinea pig thymocytes, while ConA was by far a better stimulator than PHA for mouse thymocytes. All four B-cell mitogens tested (MER, DS, PPD and LPS) activated DNA synthesis in mouse lymphoid cells while only MER and DS were effective in guinea pig lymphocytes. A guinea pig spleen cell population depleted from B cells was not stimulated, neither by DS nor by MER, while it still responded to PHA and ConA. These results indicate that the proliferative response due to MER and DS occurs in the B-cell compartment. It is suggested that the differences between guinea pigs and mice with respect to their ability to develop a cell-mediated type immunity and to respond to T-independent antigens are related to differences in the relative proportions and degrees of maturation of T- and B-cell subpopulations, as reflected by the selective responsiveness to various mitogens.

[Serum bilirubin determination in newborn infants. A new micromethod for the determination of serum of plasma bilirubin in newborn infants]

A micro-method for determination of bilirubin concentration (c) of plasma or serum from newborns was developed. Photometer-readings of the extinction (E) of diluted serum (S) at the bilirubin absorption-band were done against diluted serum as blank, made free from bilirubin by the oxydative power of Chloramin T. Reagents: 1/15 M Na2(HPO4)/K(H2PO4) buffer pH 7,4 (B) and 2 g/dl Chloramin T in B(C). Blank: 0,6 ml C + 0,02 ml S; sample: 0,6 ml B + 0,02 ml S. Reaction time: 4--8 min; filter Hg 436 nm; 1 cm light-path. c (mg/dl) = E X 43,5. Accuracy was determined by a calibration curve (x: mg/dl c of diazo-method; ): E of micro-method); b = 1,008. Reproducibility in series at 14,2 mg/dl resp. 47,9 mg/dl was 1,5% resp. 1,6%. Linearity between E and c is good up to 48 mg/dl c. Specifity was only reduced by serum hemoglobin (h). Sodium heparinate (50 E./ml S) and carotin (952 microgramm/1) had no effect upon E; plasma anticoagulated with heparinate therefore can be used instead of serum. Concentration of h is without importance for clinical purposes; 100 mg/dl h causes about 0,2 mg/dl wrong depression of c.

Effect of dopamine on renin secretion in the anesthetized dog

Intrarenal perfusion of dopamine (6 mug/kg/min for 10 min) caused a significant increase of renin secretion, together with a significant increase in renal blood flow. This renin hypersecretion is not accompanied by any significant alteration in renal perfusion pressure, kalemia or natriuresis. The role of intrarenal dopaminergic receptors has been studied: (a) Haloperidol (intrarenal perfusion of 50 mug/kg/min for 20 min) suppresses the renal vasodilation and renin hypersecretion induced by dopamine. (b) Propranolol (intrarenal perfusion of 1 mg/kg in 15 min, then of 4 mg/kg/hr) alters neither the renal vasodilation nor the renin hypersecretion induced by dopamine. These observations support the assumption that the dopaminergic receptors are brought into play in the two renal responses to dopamine studied by us.

Transplantation of human cancers to nude mice and effects of thymus grafts

Human cancers were transplanted to nude mice; a cell line originating in the foregut (distal stomach or first portion of the duodenum) produced exponential nonmetastasizing growth, preventable by prior thymus implantation. Implantation of thymuses into mice with established tumors resulted in increased animal survival and in four instances in complete regression of the neoplasm. Cell lines of pancreatic carcinoma and melanoma and surgical specimens of melanoma and of neoplasms from the pancreas and colon showed variable growth patterns in this system. Repeated attempts to transplant gastric adenocarcinoma were unsuccessful.

beta-blocking drugs and renin secretion in the anaesthetized dog

1. The effect of propranolol and sotalol on renin secretion was studied in the anaesthetized dog. 2. beta-adrenergic blockade did not modify basal renin secretion and did not affect the rise of renin secretion induced by haemorrhage or aortic constriction. 3. beta-adrenergic blockade diminished the rise in renin secretion induced by stimulation of the renal nerves.