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R Scheer

Publications and source records attributed to R Scheer.

10 recordsLinked to original sources
PubMed1993

[The effect of mistletoe lectins on the limulus amebocyte lysate test].

Former reports about too high and from batch to batch changing endotoxin contents in mistletoe preparations and phytopharmaceuticals for parenteral administration correlated with clinically observed side effects led to investigations of the endotoxin content of ABNOBA-viscum. For that purpose the endotoxin levels of the raw materials, the equipment and the production steps were observed by using the limulus amebocyte lysate (LAL) test. The mean value found in the preparation containing the highest available concentration (dilution level 2 containing 15 mg of plant extract from 20 mg of fresh mistletoe in 1 ml) came to 66.7 endotoxin units (EU) per ml, corresponding to about one fifth of the commonly accepted limit value of 350 EU/ml, the human pyrogenic dose. Depending on their dilution level, lower concentrated preparations led also to lower LAL test results. It could be proved that lectins contained in mistletoe preparations cause false positive LAL tests. Such results implicate false too high contents of endotoxin. Different lysates, i.e. Limusate, Pyrogel, Pyrogent, and Pyroquant showed approximately the same results. Microbiological and LAL test results indicate that only 10% of the total amount of the LAL test result was caused by endotoxins. So it is necessary to form a new estimation of the former results of determination of the endotoxin content of mistletoe preparations.

Animals↗
PubMed1988

Serum concentration and dose-response relationships for carprofen in rheumatoid arthritis.

Thirty-eight patients with active, definite, or classical rheumatoid arthritis were tested in a double-blind, 3-week-per-arm, multiple-crossover, randomized, block-design comparison of 100, 300, 600, and 800 mg/day carprofen given b.i.d. A linear dose-response relationship was demonstrated for six of nine efficacy measures (p less than 0.052). A plasma concentration to therapeutic response relationship was shown just before or 1 to 2 hours after a dose (p less than 0.05) for seven efficacy parameters for the patients with at least three serum carprofen concentrations. By nonparametric analysis, with the patients divided into three equal groups, the percent of responders rose from 38.1% to 50% to 59.1%. Sixty-nine percent of patients responded when carprofen concentrations were greater than 10 micrograms/ml, whereas only 9% responded when they were below 1.9 micrograms/ml. Although only seven patients had limiting side effects, there was a tendency toward a dose-toxicity relationship through 600 mg daily carprofen.

Adult↗
PubMed1988

[Microbial growth in mixed-bed ion exchange columns].

The microbial growth in ion-exchange columns of Christ GmbH Leonberg (Germany) was studied under differing water processing conditions. Continuous processing led to the same or slightly higher microbial counts in the product water compared to the feed water. Feeding the considerably contaminated column with slightly contaminated water (less than 40 CFU/100 ml) also didn't prevent microbial growth in the column. If water was withdrawn on demand only, an overnight no-demand period with closed inlet of the column led to considerable microbial growth, raising the microbial counts of the product water to well above the feed water level. But lower microbial counts were found in the product water than in the feed water by tightly closing the outlet of the column and hereby keeping the column at the same pressure as exists in the piping system. This was observed in several months long experiments operating with disinfected as well as freshly regenerated resin. The passage through a column of freshly regenerated resin led to a germ reduction of approximately 2 powers of ten and to an elimination of pyrogens.

Bacteria↗
PubMed1979

Alteration of cortical orientation selectivity: importance of asymmetric input.

Rearing cats so that each of the two eyes sees stripes of a different orientation alters the orientation preference of visual cortex cells. This result can be obtained by rearing the cats in striped cylinders or with goggles attached to their faces, but a tighter control of orientation preference is achieved by the goggles.

Animals↗