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Biomedical subjects

L Persson

Publications and source records attributed to L Persson.

At least 253 records · Page 14Linked to original sources
PubMed1982

Antibodies to ornithine decarboxylase. Immunochemical cross-reactivity.

L-Ornithine decarboxylase was purified to apparent homogeneity from the kidneys of testosterone-treated mice. Antibodies to ornithine decarboxylase were raised in a rabbit using the purified enzyme. Ouchterlony double diffusion technique revealed a single precipitin line between the antiserum and purified mouse kidney ornithine decarboxylase. The antibodies inhibited ornithine decarboxylase from various tissues of mice and rats to the same extent, indicating a close immunological relationship. S-Adenosyl-L-methionine decarboxylase and L-histidine decarboxylase from mouse kidney as well as ornithine decarboxylase from Escherichia coli were unaffected by the antibodies.

Animals↗
PubMed1981

Putrescine turnover in kidneys of testosterone-treated mice.

Putrescine turnover was studied in testosterone stimulated mouse kidney after labeling the endogenous pool of putrescine with the polyamine precursor [3H]ornithine. Renal putrescine was rapidly labeled after the administration of radioactive ornithine, reaching maximal activities at the time of the earliest measurement (5 min after injection). The content of labeled putrescine then declined extremely rapid with a half-life of about 15 min. Treatment with the diamine oxidase inhibitor, aminoguanidine, did not affect this rapid turnover. The decline in radioactive putrescine was not accompanied by an increase in labeled spermine. However, testosterone treatment resulted in a marked increase in urinary content of both labeled and unlabeled putrescine indicating that most of the newly synthesized renal putrescine is excreted in the urine.

Animals↗
PubMed1981

Polyamine metabolism as related to growth and hormones.

Previous work had revealed a connection between high histamine formation and certain types of rapid growth. Since then evidences have accumulated that diamines abd polyamines affect an impressive number of reactions pertinent to cell growth and proliferation. In studies on polyamine metabolism as related to growth and hormones we have preferentially been working with three types of biological model systems, i.e. the pregnant rat, the gonadotrophin stimulated rat ovary and the mouse kidney induced to growth by androgenic or anabolic steroids.

Amine Oxidase (Copper-Containing)↗
PubMed1980

Polyamine metabolism in mouse kidney after administration of mercuric chloride.

Testosterone administration to gonadectomized male mice, besides giving rise to a distinct hypertrophy of the kidneys, results in a large increase in renal ornithine decarboxylase activity and accumulation of polyamines. Experiments were performed to examine the effects of localized renal injury caused by mercuric chloride administration on the polyamine metabolism in the testosterone stimulated mouse kidney. A single injection of mercuric chloride resulted in severe damage of tubular epithelium primarily in the proximal convolutions situated in the cortex and outer medullary stripe. Although the injection of mercuric chloride to testosterone treated mice decreased the stimulation of ornithine decarboxylase activity it did not prevent the increase in the concentration of putrescine. The levels of spermidine as well as of RNA were elevated. These results may indicate early reperative growth following mercuric chloride administration. The observations are discussed in relation to the effects of 1,3-diaminopropane, another nephrotoxic agent on renal growth and polyamine metabolism.

Animals↗
PubMed1980

Antibiotic resistance patterns of coliform bacteria isolated from food.

308 strains of coliform bacteria isolated from food of various origin were identified and their resistance patterns were studied. The strains belonged to 10 different species and Escherichia coli was the most common. Coliforms isolated from samples incubated at 44 degrees C were more often identified as E. coli than coliforms isolated from samples incubated at 37 degrees C. Klebsiella and Enterobacter spp. taken together were, on the contrary, mor often isolated at 37 degrees C than at 44 degrees C. E. coli was most frequently isolated from raw meat and egg products. Klebsiella dn Enterobacter spp. more often in other types of products. 54% of the strains were resistant to at least one of the 9 antibiotics tested. Resistance to nitrofurantoin and sulphaisodimidine was most frequent (30 and 25% respectively). No strain resistant to streptomycin, neomycin or trimethoprim/sulphamethoxazole was registered. 40% of the resistant strains were multiresistant. The lowest number of resistant strains was recorded from custards and desserts and from raw meat products (42 and 46% respectively) and the highest from ice-cream (89%). Multiresistant strains were recorded most frequently from pasteurized milk products, custards and desserts. None of the 66 multiresistant strains tested could transfer the resistance to E. coli in vitro. The results do not indicate that food of animal origin in Sweden represents a source for bacteria with transferable resistance determinants.

Anti-Bacterial Agents↗
PubMed1979

Canine hip dysplasia: study of heritability in 401 litters of German Shepherd dogs.

Heritability of hip dysplasia was estimated to be about 0.4 to 0.5 when based on the radiographic evaluations of the hip joints of 2,404 German Shepherd Dogs born at The Armed Forces Dog Training Center in Sweden. The material included all dogs in 401 litters born at the Center from 1965 through 1973 that reached the age of 15 months. To be expected with such high heritability, frequency of hip dysplasia in the offspring was shown to be affected by the hip joint status of sire and dam as well as by the hip joint status of their parents and littermates. Even matings between sires with normal hip joints and dams with only slight dysplasia resulted in significantly higher frequency of hip dysplasia in the offspring, when compared with the frequency if both sires and dams had normal hip joints. Frequency of hip dysplasia in the progeny of sires with normal hip joints varied greatly. Since 1973, selection of the breeding stock has been based on hip joint status (phenotype) of the breeding animals and of their relatives as well as on what had become known about frequency of hip dysplasia in the litters already born (progeny testing). In this way, frequency of hip dysplasia in 347 dogs born at the Center during 1975 was lowered to 28%. This figure should be compared with the figure of 50%, which represents the frequency of hip dysplasia in the kennel up to 1970, when selection was not as strict as could be expected in a well-controlled kennel.

Animals↗
PubMed1979

Polyamine metabolism in the kidneys of castrated and testosterone-treated mice after administration of methylglyoxal bis(guanylhydrazone).

The effects of methylglyoxal bis(guanylhydrazone) on S-adenosyl-L-methionine decarboxylase (EC 4.1.1.50) activity were studied in the mouse kidney stimulated to growth by testosterone administration. The drug was found a potent inhibitor of the enzyme in vitrol Administration of methylglyoxal bis(guanylhydrazone) in vivo resulted in a transient inhibition followed by a strong enhancement of the enzyme activity. Dialysis of the kidney extract, to remove remaining methylglyoxal bis(guanylhydrazone), revealed a great and rapid increase in the activity of S-adenosyl-L-methionine decarboxylase. Injections of testosterone to castrated mice resulted in a marked increase in kidney weight and an accumulation of renal putrescine, spermidine and spermine. These effects of testosterone could not be blocked by simultaneous injections of methylglyoxal bis(guanylhydrazone). It appears that due to secondary effects by which the inhibition of methylglyoxal bis(guanylhydrazone) on S-adenosyl-L-methionine decarboxylase activity is circumvented the inhibitor seems to be of uncertain value in attempts to decrease selectively the in vivo levels of polyamines.

Animals↗
PubMed1979

Latent herpes simplex virus trigeminal ganglionic infection in mice and demyelination in the central nervous system.

Mice were inoculated with herpes simplex virus (HSV) type 1 by gently scraping the skin of the nose with a fine needle. About 80% of the animals developed latent inapparent HSV infections in trigeminal ganglia. Virus was demonstrable for at least 6 months post inoculation (p.i.) by cocultivation of ganglionic tissue with GMK cells. Histologically, trigeminal ganglia revealed infiltrations of inflammatory cells even 6 months p.i. In addition, lesions occurred in the brainstem corresponding to the entry of trigeminal roots, trigeminal tracts and nuclei. Inflammatory cell infiltration, disruption of myelin sheaths and macrophages laden with myelin degradation products were observed 7 days p.i. Fourteen to 30 days p.i. electron microscopy demonstrated completely naked axons. In the transitional region of the trigeminal root denuded axons occurred in the central part of the region while the peripheral myelin, bordering the demyelinated central segments, was intact. Small areas of demyelination were still detectable 3 and 6 months p.i. but there were then also signs of remyelination. Possible mechanisms causing the demyelinations are discussed.

Animals↗
PubMed1979

Effects of 1,3-diaminopropane on testosterone induced hypertrophy and polyamine synthesis in mouse kidney.

The effects of prolonged treatment with 1,3-diaminopropane, a structural analogue of putrescine, on polyamine metabolism and growth in kidney tissue, were studied in mice in which renal hypertrophy was induced by testosterone treatment. Injections of 1,3-diaminopropane resulted in an almost total suppression of the testosterone induced stimulation of ornithine decarboxylase activity and prevented the accumulation of putrescine and spermidine in the kidneys. Renal spermine concentration was even lowered. Administration of 1,3-diaminopropane effectively prevented the testosterone induced increase in renal weight and RNA. In mice receiving 1,3-diaminopropane proteinuria was observed and histological examination revealed renal damage. Due to the nephrotoxic action of 1,3-diaminopropane caution is essential in relating the prevention of renal hypertrophy and the inhibition of polyamine synthesis.

Adenosylmethionine Decarboxylase↗
PubMed1978

14-3-2 protein in rat brain.

The distribution of the 14-3-2 protein in rat brain was investigated by immuno-electron microscopy using antiserum to the protein conjugated with peroxidase. 14-3-2 was demonstrated in the nuclear membrane, the endoplasmic reticular membranes and in the plasma membrane of nerve cells. The protein was also localized to the presynaptic densities and to the pre- and postsynaptic membranes. It could not be demonstrated in the membranes of the Golgi complex, inner membrane of mitochondria or in the nucleoplasm of neurons. No 14-3-2 protein was found in astrocytes, oligodendrocytes or in non-neuroectodermal tissue elements.

Animals↗