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K Bernhard

Publications and source records attributed to K Bernhard.

At least 19 recordsLinked to original sources
PubMed2001

Photo- and radiation-chemical formation and electrophilic and electron transfer reactivities of enolether radical cations in aqueous solution.

In aqueous solution, enolether radical cations (EE.+) were generated by photoionization (lambda < or = 222 nm) or by electron transfer to radiation-chemically produced oxidizing radicals. Like other radical cations, the EE.+ exhibit electrophilic reactivity with respect to nucleophiles such as water or phosphate as well as electron transfer reactivity, for example, towards one-electron reductants such as phenols, amines, vitamins C and E, and guanine nucleosides. The reactivity of these electron donors with the radical cation of cis-1,2-dimethoxyethene.+ (DME.+) can be described by the Marcus equation with the reorganization energy lambda = 16.5 kcalmol(-1). By equilibrating DME.+ with the redox standard 1,2,4-trimethoxybenzene, the reduction potential of DME.+ is determined to be 1.08 +/- 0.02 V/NHE. The oxidizing power of the radical cation of 2,3-dihydrofuran, which can be considered a model for the enolether formed on strand breakage of DNA, is estimated to be in the range 1.27-1.44 V/NHE.

Journal Article↗
PubMed2001

(9Z)-capsanthin-5,6-epoxide, a new carotenoid from the fruits of Asparagus falcatus.

From the fruits of Asparagus falcatus a novel minor (Z)-carotenoid has been isolated and, on the basis of spectral data interpretation, characterized as (9Z)-capsanthin-5,6-epoxide [(9Z,3S,5R,6S,3'S,5'R)-5,6-epoxy-3,3'-dihydroxy-5,6-dihydro-beta,kappa-caroten-6'-one, (1)]. In addition, seven other (Z)-carotenoids [namely, (9Z)-, (9'Z)-, (13Z)-, and (13'Z)-capsanthins, (9Z)- and (13Z)-capsorubins, and (9Z)-violaxanthin], which have been previously described from other plants, were isolated and identified.

Asparagus Plant↗
PubMed1987

[Demonstration of rectal myiasis in humans].

During a period of over 10 years 4 cases (2 women; 2 men) of rectal myiasis were observed after periods of warm weather. The patients had interpreted myiasis as a symptom of infestation with worms. In 3 cases maggots of Fannia canicularis (Linnaeus, 1761) and in one case maggots of Muscina stabulans (Fallén, 1816) could be found. The patients had only minor complaints.

Adult↗
PubMed1986

[House dust mites in bed dust and on the body].

In the urine of a ten-year-old girl mites of the species Tarsonemus minusculus (Can et Fanz.) and Cheyletus eruditus (Schr.) were found. A following examination of the bed dust from the bed of the child produced yet two further species of house dust mites Dermatophagoides pteronyssinus (Trouess) and Tyrophagus putrescentiae (Schr.). The demonstration of Tarsonemus minusculus in this area is new, just as the hitherto unknown male of this species.

Animals↗
PubMed1980

[Intestinal helminths in the DDR district of Rostock].

The population of a rural municipality in the district of Rostock including the staff members of a research institute at that place, who daily go there from a nearby city, were examined helminthologically (as a whole 910 persons). 1.5% of these persons were affected by helminths. Comparative examinations with 407 animal breeders of other municipalities showed the same results (also 1.5%). The examination of seamen going to the trophics (1471 persons) showed other results: 3% were attacked. Foreigners from the tropics staying in the district of Rostock during the same period of time (426 persons) were affected far more: 88%.

Ascariasis↗
PubMed1979

[The effects of the xenon arc lamp upon the iris of the pigmented rabbit eye (author's transl)].

The ultrastructural alterations of 10 pigmented rabbit irides 15 minutes to 257 days after irradiation with a xenon arc lamp were analysed. Pulse duration was varied while irradiation power was kept constant at 3.24 W. 0.32 J (= 100 ms pulse duration) were delivered to the left eye and 3.2 J (= 1 second pulse duration) to the right side. The area of damage event was considerably smaller at the lower energy level. However depth of the crater was the same at both higher and lower levels. Cells and organelles disintegrate forming lamellar structures and coarse granules. The shape of the pigment granules remains intact. Collagen fibres disintegrate into subunits loosing their periodicity. Mesenchymal cells cover the area of damage few days after irradiation at the low energy level. A thin scar remains at the impact site. High energy irradiation shifts the equilibrium towards degenerative phenomena. Secondary degenerative processes are powerful enough to induce a total decay of the iris substance. The reactivity of the iris irradiated by a xenon arc lamp thus depends from either irradiation duration, power level or from both (energy).

Animals↗
PubMed1978

Bacteriocin and antibiotic resistance plasmids in Bacillus cereus and Bacillus subtilis.

A number of plasmids have been isolated as covalently closed circular DNAs from strains of Bacillus cereus and B. subtilis. From 12 out of 15 strains of B. cereus, plasmids could be isolated. Most of the B. cereus strains contained two or more plasmids. Their molecular weights ranged from 1.6 X 10(6) to 105 X 10(6). Bacteriocin production could be attributed to a 45 X 10(6)-dalton plasmid (pBC7) from B. cereus DSM 336, and tetracycline resistance to a 2.8 X 10(6) plasmid (pBC16) from B. cereus GP7. Two streptomycin-resistant strains of B. subtilis harbored plasmids of 5.2 X 10(6) and 9 X 10(6), respectively, which were, however, not correlated with the antibiotic resistance. The plasmid carrying resistance to tetracycline, pBC16, which was originally isolated from B. cereus, could be subsequently transformed in B. subtilis, where it is stably maintained.

Anti-Bacterial Agents↗
PubMed1976

[Malignant hyperthermia: attempt at an early diagnosis by means of determination of creatine phosphokinase (CPK) and its isoenzymes].

Creatinphosphokinase (CPK) was elevated in sera of patients with malignant hyperthermia and in sera of some of their relatives. Only the MM-isoenzyme (but not the MB- or the BB-isoenzyme) could be detected by paperchromatographic analysis. In some of the patients elevation of muscle aldolase was also observed. Thus, the appearance of the BB-isoenzyme in sera of patients with malignant hyperthermia, as described by another group of investigators, was not confirmed. No specific screening method exists as yet to detect patients with a high risk of developing this often lethal reaction to anesthesia. However, in patients without muscle disease or trauma and without prior i.m. injections, myocardial infarction or major physical strain, elevation of CPK in serum should be interpreted as meaning that malignant hyperthermia may develop during anesthesia. The pathophysiology of malignant hyperthermia is discussed.

Creatine Kinase↗