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Biomedical subjects

J Sander

Publications and source records attributed to J Sander.

At least 55 records · Page 3Linked to original sources
PubMed1993

New neonatal thyrotropin enzyme immunoassay with fluorimetric detection: comparison with time-resolved fluoroimmunoassay.

This short communication compares a novel fluorimetric microplate enzyme immunoassay (FEIA) with a commercial time-resolved fluoroimmunoassay for the determination of thyrotropin in dried blood spots. The evaluation was performed using a retrospective study design with newborn blood samples from three screening centres. Non-parametric Spearman rank correlation analysis revealed highly significant positive correlation between methods: rs = 0.465, p < 0.0001 (Hannover), rs = 0.659, p < 0.0001 (Minsk), rs = 0.755, p < 0.0001 (Helsinki). Wilcoxon signed rank test performed for paired FEIA and time-resolved fluoroimmunoassay showed that the results obtained by both tests represented the same distribution (p < 0.0001). The new method, using fluorimetric detection, can be performed with the instrumentation commonly used for the screening of congenital hypothyroidism and phenylketonuria. Results are obtained within three to four hours after arrival of the sample in the laboratory. Preliminary evaluation indicates the method to be a suitable alternative to time-resolved fluoroimmunoassay for neonatal thyroid function screening.

Congenital Hypothyroidism↗
PubMed1992

[Infection control in Norwegian somatic hospitals 1990].

The authors present results from a survey of infection control in Norwegian somatic hospitals, carried out during summer/autumn 1990. In 15 of 74 hospitals (20%) one of the hospital doctors was appointed as responsible for infection control. 35 hospitals (48%) had an infection control nurse. Only nine hospitals (12%) reported routine prospective surveillance of hospital infections. The survey revealed a clear under-utilization of commonly accepted methods to survey and prevent hospital infections. Many of the respondents stated the need for national guidelines for infection control. The health authorities should take the initiative to remedy this situation. A new law concerning secondary health care will be passed in the near future, requiring hospitals to establish effective quality assurance systems. Infection control is a very concrete example of quality assurance, and should be given priority when setting up quality assurance systems for hospitals.

Cross Infection↗
PubMed1992

[Fluoroquinolones--a new and important group of antimicrobial agents].

The fluoroquinolones ciprofloxacin (Ciproxin) and ofloxacin (Tarivid) have recently been marketed in Norway. Fluoroquinolones are active against most Gram-negative aerobic pathogens, but have a relatively poor impact on Gram-positive organisms. Mutation in the gyrase-A-gene of a bacteria may lead to resistance to all quinolones. There is little cross-resistance towards other antibiotics. A strong tendency to resistance has been observed among Pseudomonas, Staphylococci and Enterococci. Ciprofloxacin and ofloxacin are administered orally, and are distributed well in the body. The dose should be reduced in elderly patients. Approximately 10% experience adverse effects, mostly in the gastrointestinal and central nervous systems. Ciprofloxacin and ofloxacin are used mainly in the treatment of recurrent and/or complicated urinary tract infections. Other indications include gonorrhea, serious gastrointestinal infections and chronic Salmonella carrier states.

Anti-Bacterial Agents↗
PubMed1992

Colorimetric determination of galactose and galactose-1-phosphate from dried blood.

A colorimetric microassay for the simultaneous quantitative determination of galactose (Gal) and galactose-1-phosphate (Gal-1-P) in dried blood spots is described. An enzymatic reaction involving alkaline phosphatase (EC 3.1.3.1) and galactose dehydrogenase (EC 1.1.1.48) produces NADH, which is coupled with diaphorase (EC 1.8.1.4) and iodonitrotetrazolium violet (INT). The colourless INT is converted to a formazan of red colour the intensity of which is quantitated either photometrically by a microplate reader or determined visually with sufficient sensitivity for screening purposes. We evaluated the assay on 200,000 blood samples in a newborn screening program, and were able to distinguish between classical and milder forms of galactosemia with ease.

Alkaline Phosphatase↗
PubMed1991

[Biotinidase deficiency. Results of neonatal screening 1985-1989 in Lower Saxony].

During a five-year-period (1985-1989) 420,000 newborns in Lower Saxony, FRG, were screened for biotinidase deficiency using biotinyl-para-amino-benzoic-acid as substrate. Three newborns with profound biotinidase deficiency (activity 1.1%, 2.1%, 2.3% of mean normal activity level) were detected. Nine newborns had partial biotinidase deficiency (activity 17-26% of mean normal activity level), thus giving an incidence of 1:140,000 with profound, and 1:46,667 with partial biotinidase deficiency, respectively. The infants with profound biotinidase deficiency are treated with biotin (2 x 5 mg/day) from the 3rd, 6th and 8th week of life and have developed normally so far. The children with partial biotinidase deficiency are not treated but followed up closely. The necessity of newborn screening for biotinidase deficiency is stressed.

Amidohydrolases↗
PubMed1990

A new approach to the newborn screening for hyperphenylalaninemias: use of L-phenylalanine dehydrogenase and microtiter plates.

We adapted the recently described colorimetric method for the specific determination of phenylalanine to a microplate assay using a NAD(H)-dependent L-phenylalanine dehydrogenase. With respect to sensitivity, analytical recovery and interrun imprecision this method for measuring phenylalanine in eluates of paper-dried blood spots is suitable for routine newborn screening for hyperphenylalaninemias. In contrast to the microbiological Guthrie assay, with the enzymatic method quantitative data may be obtained on the same day, also in the blood of newborns on antibiotic treatment.

Amino Acid Oxidoreductases↗
PubMed1990

Regulation of prostaglandin E2 synthesis in human amnion by protein kinase C.

A role for protein kinase C (PKC) in mediation of prostaglandin E2 synthesis in human amnion cells has been suggested. We have investigated the specificity of the stimulation of PGE2 synthesis by phorbol esters and employed putative PKC inhibitors to demonstrate the specificity of PKC stimulation. The three phorbol esters, tetradecanoyl phorbol-13-acetate, phorbol-12,13-dibutyrate and phorbol-12,13-didecanoate gave concentration-dependent (10(-10)-10(-7)M) increases in PGE2 synthesis when added to amnion cells in monolayer, however, no effect was seen with the structurally similar phorbols phorbol-12-13-diacetate, 4 alpha phorbol-12-13-didecanoate or phorbol base. The stimulatory effect of TPA (10(-8)M) on amnion PGE2 synthesis could be prevented by coincubation with the putative protein kinase C inhibitors 1-(5-isoquinoline sulphonyl) piperazine, 1-0-octadecyl-2-0-methyl-rac-glycero-3-phosphocholine, sphingosine and chlopromazine at concentrations of 10(-6)-10(-4)M. Addition of the transcription inhibitor actinomycin D at 10(-6)-10(-5)M prevented TPA (10(-8)M)-induced PGE2 synthesis. However, paradoxically, a further increase in PGE2 synthesis was seen when 10(-9)-10(-7)M actinomycin D was added together with TPA. The phospholipase A2 inhibitor quinacrine was able to prevent the TPA-induced increase in PGE2 synthesis even in the presence of exogenous arachidonic acid suggesting that phospholipase A2 may be a target for PKC action.

Amnion↗
PubMed1987

[Nitrate concentration in drinking water in southwest Lower Saxony].

The investigation of 8544 water samples from central water supply plants and of about 20,000 from own water supply plants of Southwest Lower Saxony with respect to nitrate pollution showed that 97.5% of the samples from the central water supply plants and of 63.6% from the own water supply plants contained nitrate concentrations lower than 50 mg/l. On the other hand, the nitrate concentrations of samples from own water supply plants were in 12.5% more than 90 mg/l and in 24.0% between 50 and 90 mg/l. There was a remarkable tendency of increasing of the nitrate pollution comparing the data from 1979 and 1984. The nitrate concentrations correlated well with the depth of the wells but not with bacteriological findings.

Enterobacteriaceae↗
PubMed1986

[Results of a pilot study of neonatal screening for congenital biotinidase deficiency].

Biotinidase activity was determined in a pilot study of 78,000 dried blood samples on filter paper. In the assay the liberation of p-aminobenzoic-acid from biotinyl-p-aminobenzoic-acid by biotinidase is tested. One boy was identified to be with biotinidase deficiency. Transient reduction of biotinidase activity to virtually negative test results was observed in 8 preterm babies (recall: 0,01%). Specificity and sensitivity of the test were nearly 100%. We suggest that screening for biotinidase deficiency should be incorporated into existing neonatal screening programs for inborn errors of metabolism. This suggestion is based on the ease of testing, the necessity for presymptomatic laboratory diagnosis, and on the effectiveness of early treatment of the multiple carboxylase deficiency caused by defective biotinidase.

Amidohydrolases↗
PubMed1986

[Screening for congenital hypothyroidism with an immunoradiometric assay (IRMA) for thyroid stimulating hormone].

A commercial immunoradiometric assay (IRMA) for thyroid stimulating hormone (TSH) was modified to be used with dried blood on filter paper of our neonatal screening programme. Sensitivity and precision were as good as with the conventional radioimmunoassay (RIA), but the IRMA was faster. In addition the IRMA was extremely cheap, because all kit reagents could be prediluted 1:4. Our screening procedure for congenital hypothyroidism now combines a determination of TSH with the IRMA technic and a determination of free thyroxin (FT4) by radioimmunoassay. The kit for FT4 can be diluted 1:3, as described earlier. The combination of TSH-IRMA und FT4-RIA to our knowledge is not only much faster but also considerably cheaper than measuring one parameter with consecutive retesting of suspicious samples, which is the procedure in some countries. As the combination gives two independent results it is also of greater clinical value than measuring TSH in dublicates, which is still officially recommended in the Federal Republic of Germany.

Antibodies, Monoclonal↗