Biomedical subjects

H R Koch

Publications and source records attributed to H R Koch.

5 recordsLinked to original sources

PubMed1978

Experimental cataracts in rats due to tryptophan-free diet.

A tryptophan-free diet induces posterior subcapsular cataracts and reversible corneal opacities in young Wistar rats. Compared to the controls there is a significant decrease of body weight, lens fresh weight, and water-soluble lens protein. Protein separation by isoelectric focusing shows diminished alpha-, beta-, and gamma-crystallin fractions. If tryptophan is restored to the diet after 24 days, new clear lens fibers are laid down again, indicating that the mechanism of protein synthesis has not been permanently damaged by tryptophan-deficiency.

Animals↗

PubMed1977

Phenol oxidase activity of the iris and the ciliary body in rats.

Phenol oxidase activity of the iris and the ciliary body in normal young rats of three differently pigmented strains, Lewis (albino), E3 (light brown, hooded), and BDE (black, hooded), was studied using DL-Dopa. Applicability of the histochemical method was controlled with skin samples taken from the necks of the animals. In the pigmented strains, the appearance of newly formed pigment at the pigmented epithelium and stroma of the iris and ciliary body was observed. In the E3 animals, the reaction was slightly positive, while in the BDE rats it was more pronounced. No phenol oxidase activity was detected in the ocular structures of the albinotic rats.

Animals↗

PubMed1977

[Fistulating operations with Walser's punch Modifications without scleral flap and with fixed or loose scleral flap (author's transl)].

Long term results of fistulating operations with Walser's punch are reported. A comparison between two methods without and with fixed scleral flap shows that the first method was more often associated with hypotonia, while the latter is more often followed by unsatisfactory pressure regulation necessitating additional drug therapy. That is why a third method of operation was developed. Here the scleral flap is shortened by scissors and not resutured to the sclera. The first clinical results indicate that the method makes use of the advantages of a scleral flap with less risk of an insufficient pressure regulation.

Glaucoma↗

PubMed1977

[Lens induced myopia in steroid cataracts (author's transl)].

Longterm investigations of patients on immun-suppressive corticosteroid therapy showed that the development of advanced corticosteroid cataracts is accompanied by a marked increase of lens myopia up to 7.5 dpt. It can be assumed that this phenomenon is due to the optical effect of the discoid posterior subcapsular opacities.

Adrenal Cortex Hormones↗

PubMed1976

[The influence of cortisol treatment on the development of diabetic cataracts in rats (author's transl)].

The influence of daily subcutaneous cortisol injections (10 mg/kg) on the development of cataracts in streptozotocine (STR) diabetes was studied in 6 groups of Wistar rats (n = 10). Cataracts occurred only in the two groups subjected to high STR doses (60 mg/kg). We were astonished to find that in cortisol-treated diabetic animals there were lower blood glucose levels, fewer cases of glucosuria, and less pronounced cataracts than in rats treated with STR only. As STR had been administered after the start of cortisol therapy, it is assumed that the steroid had caused a protection of pancreatic B cells against STR and the onset of a less severe diabetes.

Animals↗