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Biomedical subjects

R Kirsch

Publications and source records attributed to R Kirsch.

At least 55 records · Page 3Linked to original sources
PubMed1986

Is mucus involved in biocrystallization? Study of the intestinal mucus of the sea-water eel Anguilla anguilla L.

Freeze-dried intestinal mucus of sea-water-adapted eels was analysed by scanning electron microscopy (SEM) and X-ray microanalysis. Calcite crystals were observed in the mucus fibres; their concentration increased along the hindgut. Random SEM observations made in situ indicated that mucus fibres were involved in the genesis of these crystals. Calcium-rich mucus globules were found fused inside crystal matrices. Single typical rhombohedric crystals of various complexity appeared within the mucus framework. The steps of crystal biogenesis were reconstituted in in-vitro conditions.

Anguilla↗
PubMed1986

[Pathology and control of virus-induced enteritis in calves].

Considerable economic loss can arise from virus-caused enteritis in calves, in the form of so-called infectious factor diseases, which often develop more seriously when bacterial organisms, such as E. coli become involved. Rota-, corona- and parvoviruses are of particular interest. These pathogens have a marked predilection for intestinal epithelium. Rotavirus destroys the epithelial cells of the upper parts of the villi. Coronavirus penetrates to the base of the small intestinal villi and the superficial and crypt colonic epithelium is frequently affected. Infection of the small intestinal crypt epithelium is characteristic of parvovirus; loss of epithelium at the villus tip is also observed. Damage of the mucosa results in a reduction in digestive and absorbing capacity. It is not possible to treat these virus strains specifically. Great importance is therefore attached to the vaccination of dams as immune prophylaxis. Consumption of sufficient colostrum and milk from vaccinated dams affords the calves good protection. The mechanism is based on the presence of milk antibodies in the calf's intestine which neutralise orally ingested pathogens.

Animals↗
PubMed1984

Oxygen consumption in the tortoise, Testudo hermanni G., subjected to sudden temperature changes in summer and autumn.

A respirometer for long-term measurements of oxygen consumption in terrestrial vertebrates is described. The tortoise, Testudo hermanni Gmelin, investigated in summer and autumn, presents a day-night rhythm of oxygen consumption at 28 and 18 degrees C but not at 8 degrees C. The standard metabolic rate presents an important and constant thermal dependence in the range 8-18-28 degrees C.

Acclimatization↗
PubMed1983

Failure of repeated injection sclerotherapy to improve long-term survival after oesophageal variceal bleeding. A five-year prospective controlled clinical trial.

The role of sclerotherapy in long-term management after oesophageal variceal bleeding was assessed by comparing repeated sclerotherapy by means of a rigid oesophagoscope in 37 patients with control medical management in 38 patients. Varices were eradicated in 21 of the 22 patients analysed (95%) in the sclerotherapy group, but recurred in 13 of the 21 patients (average 21.5 months). Varices persisted in 13 of 14 surviving controls. The sclerotherapy patients had fewer recurrent bleeds than control patients (43 versus 73); the majority occurred before variceal eradication and were mild. However, there was no difference in survival in the two groups. The commonest cause of death was liver failure (37 patients). 32 complications occurred in 24 patients during 258 injections. Repeated sclerotherapy failed to improve survival in this trial, although varices were eradicated and recurrent variceal bleeds were prevented with adequate follow-up.

Acute Disease↗
PubMed1982

Central nervous system immunoreactive somatostatin, substance P and metenkephalin concentrations in experimental hepatic encephalopathy in the rat.

Immunoreactive somatostatin, substance P and met-enkephalin concentrations were measured in various regions of the rat brain 65 hours after portacaval shunt and compared with concentrations in sham-operated animals. No significant difference was detected in any of the three peptides in the regions studied, suggesting that these peptides do not play a role ion the pathogenesis of hepatic encephalopathy.

Animals↗
PubMed1982

Morphological changes in trichostrongylid eggs after treatment with fenbendazole.

The influence of daily doses of 0.05-0.1 mg fenbendazole/kg body weight on egg development was tested in twenty-seven lambs artificially infected with Haemonchus contortus plus Trichostrongylus colubriformis or Ostertagia circumcincta, as well as in two additional sheep naturally infected with Nematodirus spp. Atypical eggs were detected before a reduction in the number of eggs. Atypical eggs had blastomeres of different sizes and shapes; knot-like, crater-like or bubble-like. In isolated cases eggs with atypical first larvae were recognizable. Morphologically changes eggs occurred in the reproductive organs of female O. circumcincta worms. None, or only a very small number of third stage larvae, could be cultured from the faeces of treated sheep.

Animals↗
PubMed1982

Progressive processing of ingested water in the gut of sea-water teleosts.

The European eel's oesophagus, stomach and anterior and posterior intestine were perfused separately, in vivo. The oesophagus and anterior intestine play a major part in processing of ingested water. Serosal potential differences to mucosal measured in vivo were positive in all gut segments. The C1- concentrations of luminal contents in different parts of the gut were measured in nine species of sea-water teleosts. The progressive decrease in C1- concentration resulted from local processing of the ingested sea water, and the beginnings of the oesophagus and of the intestine were the major processing sites.

Animals↗
PubMed1981

Acute bleeding varices: a five-year prospective evaluation of tamponade and sclerotherapy.

In a five-year study of massive upper gastrointestinal hemorrhage, 143 patients had esophageal varices diagnosed on emergency endoscopic examination. Seventy-one patients had active bleeding from varices and required Sengstaken tube tamponade during at least one hospital admission. The remaining patients included 33 with variceal bleeding which had stopped and 39 who were bleeding from another source. Sixty-six of the former group of 71 patients were referred for emergency injection sclerotherapy. These 66 patients were followed prospectively to August 1980, and had 137 episodes of endoscopically proven variceal bleeding requiring Sengstaken tube control followed by injection sclerotherapy during 93 separate hospital admissions. Definitive control of hemorrhage was achieved in 95% the patients admitted to the hospital (single injection 70%; two or three injections 22%). The death rate per hospital admission was 28%. No patient died of continued variceal bleeding, and exsanguinating variceal hemorrhage no longer poses a major problem at our hospital. The combined use of initial Sengstaken tube tamponade followed by injection sclerotherapy has simplified emergency treatment in the group of patients who continue to bleed actively from esophageal varices, despite initial conservative treatment.

Acute Disease↗
PubMed1979

Chloride cells and chloride exchange in the skin of a sea-water teleost, the shanny (Blennius pholis L.).

The fine structure of the skin and its importance in chloride outfluxes were investigated in a sea-water teleost, the shanny (Blennius pholis L.). The epidermis is composed of three cells types: epithelial cells, mucous cells and chloride cells. These chloride cells typically contain a great number of mitochondria and an extensive agranular reticulum extending through the whole cell body. They open at the surface of the epidermis into an apical pit. An undifferentiated small cell is often observed near these chloride cells and probably corresponds to the "adjacent chloride cell". The values of chloride outfluxes through the skin and the gills are respectively 5333+/-884 muEq.h-1.kh-1 and 4479+/-2521 muEq.h-1.kg-1; n = 6; t degrees = 13+/-0.5 degrees C. Thus the ratio between skin chloride outflux and total chloride outflux is 64.7 +/- 9.3%.

Animals↗
PubMed1978

Cutaneous respiration in seven sea-water teleosts.

The oxygen consumption of excised skin (MO2 is.cut.) and the normal cutaneous oxygen uptake by the skin in situ from the external medium (MO2 ext.cut.) were investigated in seven species of teleosts in normoxic sea water: butterfish (Pholis gunnellus L.), cod (Gadus morhua L.), five-bearded rockling (Ciliata mustela L), shanny (Blennius pholis L.), flounder (Platichthys flesus L.), sole (Solea solea L.) and eel (Anguilla anguilla L.). In the butterfish, cod and rockling, all the oxygen absorbed by the skin is consumed by the skin tissue itself, whereas in the other species there is a net inward transcutaneous oxygen flux. The gain of oxygen through the skin is obtained either by a low MO2is.cut. (shanny, flounder) and/or by high MO2ext.cut. (sole and eel). The blind side of the sole is particularly efficient in oxygen uptake. The results are discussed in relation to the biota of the different species.

Animals↗
PubMed1978

In vitro and in vivo studies on the ovicidal activity of fenbendazole.

The in vitro ovicidal activity of fenbendazole against eggs of Ostertagia ostertagi, Haemonchus contortus and Trichostrongylus colubriformis was observed using different concentrations of active principle. The optimum concentration for ovicidal activity is evidently 0.5 ppm fenbendazole. A further increase in concentration results in a decrease in activity which is probably due to physical causes. Ovicidal activity of the product is assessed by the proportion of non embryonated eggs as well as embryonated eggs which are not capable of hatching. By this method of evaluation a higher ovicidal activity is recorded. Ten h after treating sheep with fenbendazole (dose 5 mg/kg) a large number of eggs whose development was inhibited, as well as atypical eggs were detectable in the faeces. Twelve h after treatment, the capacity for development of the eggs was largely suppressed.

Animals↗
PubMed1978

[Cutaneous respiration in a Selachian (Scyliorhinus caniculus L.)].

Cutaneous oxygen consumption (Mo2) and cutaneous oxygen uptake from the external medium were investigated in an elasmobranch Scyliorhinus caniculus L. In spite of an important Mo2 (2.75 +/- 0.28 nmol.mn-1 cm-2 ; n=6) a positive net flux of oxygen through the skin takes place (2.98 +/- 0.33 nmol. mn-1 .cm-2). The skin of the dogfish in an exchanger for oxygen supplying 10% of oxygen requirements of other organs of the body in these experimental conditions (t = 13 degrees C).

Animals↗
PubMed1977

Cutaneous respiration in three freshwater teleosts.

Cutaneous oxygen consumption and oxygen uptake from the external medium were investigated in three species of freshwater teleosts:eel(Anguilla anguilla L.)(silvered stage), trout (Salmo gairdnerii R.) and tench (Tinca tinca L.). The oxygen consumption of the skin is the same in the three species: 4.5 nmol-cm-2-min-1. It accounts for 35% of total Mo2 in the eel; 23% in the tench, which lives in poorly oxygenated water; and 13% in the trout living in highly oxygenated water. Cutaneous oxygen consumption is equal to (Salmo and Tinca) or greater than (Anguilla) cutaneous oxygen uptake from the external medium. Consequently, the skin in these three species is not an oxygen exchange for the benefit of other organs.

Animals↗
PubMed1976

Ligandin and Z protein in binding of thyroid hormones by the liver.

Sephadex G-100 chromatography of rat liver supernatant after addition of [125I]T3 revealed four peaks of protein-bound radioactivity in the void volume, albumin, ligandin, and Z-containing regions, respectively. The peaks were identified by cochromatography of BSP and [125I]T3 and immonodiffusion with antiratligandin IgG and antirat Z IgG. Binding of [125I]T4 to rat liver supernatant occurred in void volume, albumin, and Z regions only. Studies in vivo reveal a pattern of [125I]T3 binding to rat liver supernatant fractions quantitatively different from that observed in vitro. [125I]T4 binding to liver supernatant fractions in vivo occurred in all four peaks. BSP or bilirubin added to liver supernatant decreased T3 and T4 binding by each fraction. Flavaspidic acid inhibited binding of T3 and T4 to albumin, ligandin, and Z protein. Phenobarbital pretreatment of rats increased binding of T3 by ligandin and of T4 by albumin-containing fractions. Circular dichroism studies with purified rat liver ligandin suggest that T3 and T4 bind competitively to the same site as does bilirubin; the association constants of T3 and T4 for ligandin are 10(6) and 10(5) M-1, respectively. T4 was bound only by purified ligandin and not by ligandin in liver supernatant. To determine whether unconjugated bilirubin interferes with hepatic uptake of T3, [125I]T3 was administered to icteric homozygous and phenotypically normal heterozygous Gunn rats. Hepatic uptake and supernatant binding [125I]T3 were significantly reduced in homozygous Gunn rats. Hepatic uptake of [125I]T3 was also reduced in vivo by infusion of BSP with or without flavaspidic acid. BSP infusion abolished [125I]T3 binding to ligandin; BSP and flavaspidic acid abolished binding to ligandin and Z. These observations suggest that ligandin and Z protein are thyroid hormone binding proteins in rat liver cytosol and may influence the net flux of iodothyronies from plasma into the liver.

Animals↗