Some extracellular matrix elements as markers of 'capillary tunnels' in hypertrophied rat heart.

We studied the distribution of the extracellular matrix proteins fibronectin (FN) and laminin (LM) in the hypertrophied hearts of spontaneously hypertensive rats (SHR), using an immunofluorescence method with specific antibodies. The immunohistochemical reaction was positive in the cytoplasm of some hypertrophied cardiomyocytes. The results showed that FN and LM can be used as markers for tunnels, i.e. intracardiocytic invaginations of the sarcolemma. The tunnels observed contained capillaries.     

Some extracellular matrix elements as markers of ‘capillary tunnels’ in hypertrophied rat heart

We studied the distribution of the extracellular matrix proteins fibronectin (FN) and laminin (LM) in the hypertrophied hearts of spontaneously hypertensive rats (SHR), using an immunofluorescence method with specific antibodies. The immunohistochemical reaction was positive in the cytoplasm of some hypertrophied cardiomyocytes. The results showed that FN and LM can be used as markers for tunnels, i.e. intracardiocytic invaginations of the sarcolemma. The tunnels observed contained capillaries.     

Ventricular fibrillation threshold during acute ischemia in hypertrophied rat hearts

Ventricular fibrillation threshold was significantly lower in hypertrophied hearts than in normal hearts. Ischemia produced by coronary occlusion reduced fibrillation threshold in both normal and hypertrophied hearts, but the maximum reduction in fibrillation threshold was observed earlier in hypertrophied hearts.     

Ventricular fibrillation threshold during acute ischemia in hypertrophied rat hearts

Summary Ventricular fibrillation threshold was significantly lower in hypertrophied hearts than in normal hearts. Ischemia produced by coronary occlusion reduced fibrillation threshold in both normal and hypertrophied hearts, but the maximum reduction in fibrillation theshold was observed earlier in hypertrophied hearts.     

Morphologic alterations induced by aflatoxin B1 in Bacillus thuringiensis (Berliner)]

Significative ultrastructural alterations shown in aflatoxin B1, treated cells of Bacillus thuringiensis are: increase of number of mesosomes which are hypertrophied, decrease of ribosomes and formation of imperfect cell septa.     

A histochemical study of denervated marsupial hemidiaphragm.

The marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. The type II muscle fibres hypertrophied up to 20 days postoperation and then regressed. However, the type I fibres hypertrophied throughout the experimental period (100 days) studied. Unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. An enhancement of the ATPase reaction in the denervated type I fibres may be due to dedifferentiation. Presumably innervation exerts a 'negative control' and prevents increase of type I fibre size in the normal hemidiaphragm.     

The increase of frost resistance of tomato plants through application of 2-chloroethyl trimethylammonium chloride (CCC)

Zusammenfassung Tomatensamen in CCC-Lösung (Konzentration 500 ppm) ausgekeimt, zeigten aktivierten Keimungsprozess bei niedriger Temperatur. Tomatenkeimlinge in Knops Nährlösung mit Zugabe von CCC (100 und 200 ppm) zeigten wesentlich erhöhte Resistenz gegen niedrige Temperaturen.     

A new quaternary ammonium compound with plant growth regulatory activity

Summary Of several quaternary ammonium derivatives tested, 1-allyl-1-(3,7-dimethyloctyl)piperidinium bromide showed the best growth-retarding activity. OnChrysanthemum morifolium the growth retardation obtained with a single application of 100–200 ppm compared favourably with that obtained from 2–3 applications of 3400 ppm of N-dimethylaminosuccinamic acid (daminozide).     

A histochemical study of denervated marsupial hemidiaphragm

Summary The marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. The type II muscle fibres hypertrophied up to 20 days postoperation and then regressed. However, the type I fibres hypertrophied throughout the experimental period (100 days) studied. Unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. An enhancement of the ATPase reaction in the denervated type I fibres may be due to dedifferentiation. Presumably innervation exerts a negative control and prevents increase of type I fibre size in the normal hemidiaphragm.I am grateful to Dr O.M. Sola and Professor B.A. Kakulas for their help and encouragement.     

Inhibition of steroidogenic activity in the adrenal cortex of rats fed benzene hexachloride (hexachlorocyclohexane)

Summary Feeding various dosages of benzene hexachloride (100, 250, 750 and 1500 ppm) in the diet to weanling male albino rats for 90 days resulted in marked hypertrophy of the adrenals with large, vacuolated cells in the cortex at 750 and 1500 ppm. Accumulation of cholesterol-positive lipids and marked reduction in the activities of steroidogenic enzymes such as ⁵ 3 HSDH, 11 HSDH, G-6-PDH and SDH were seen using histochemical methods in the adrenal cortex of rats fed 750 and 1500 ppm. The results are suggestive of steroidogenic inhibition at 750 and 1500 ppm of dietary BHC while 100 and 250 ppm did not produce any discernible changes in the adrenal cortex.Acknowledgments. The authors thank Dr Muralidhara, H.P. Ramesh and K. Nanjundiah for their help and Prof. H.B. Devaraj Sarkar, Department of Zoology, University of Mysore, for providing us facilities for histochemical work. We are grateful to Sri C.P. Natarajan, for his keen interest in this investigation.     

Hormetic concentrations of azadirachtin and isoesterase profiles inTribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

Electrophoretic pattern of esterases from larvae ofTribolium castaneum fed on a diet which included hormetic concentrations of azadirachtin (viz. 0.001, 0.01 and 0.1 ppm) for 10 d were studied. The results showed a dose-dependent variation in the multiple molecular forms of the esterases. The variations, however, were not limited to the synthesis of new isoforms or the deletion of existing ones; there was also variation in their relative abundance.     

Enhancement of boll weevilAnthonomus grandis Boh. (Coleoptera: Curculionidae) pheromone biosynthesis with JH III

Summary The juvenile hormone JH III, when incorporated at 1.0 ppm in the diet of adult male boll weevils (Anthonomus grandis Boh.), increased the biosynthesis of its 4 pheromone compounds by 3 times. The biosynthesis at lower and higher levels of JH III was less. JH I was not active at any of the concentrations tested.In cooperation with the Miss. Agr. and For. Exp. Sta., Miss. State, MS 39762. Mention of a proprietary product does not necessarily imply endorsement of this product by the USDA.     

Levels of lead on the livers of dogs from the Paris region]

Lead level has been determined in the liver of 51 Dogs of different ages, sex and breed from districts of Paris. This level is from 0,16 ppm (fresh weight) up to 5,4 ppm. 23 p. cent of Dogs examined have more than 3 ppm in their livers. The level is not correlated with sex, breed and size. It increases with age of animals.     

Anti-feedant activity of the polyacetylene,phenylheptatriyne (PHT), from the Asteraceae toEuxoa messoria (Lepidoptera: Noctuidae)

Summary Phenylheptatriyne (PHT), a polyacetylene from various species of Asteraceae reduced feeding and weight gain of larvae of the polyphagous insectEuxoa messoria when incorporated into an artificial diet at concentrations of 10–300 ppm. These results suggest a role as insect antifeedants for the widely distributed polyacetylenes of the Asteraceae.Acknowledgment. This work was supported by NSERC and Agriculture Canada (E.M.R.) We thank Dr R. J. Byers (Agriculture Canada) for eggs ofEuxoa. To whom reprint requests should be addressed.     

Lysozyme levels in tissues of iron-deficient rats

Fats were fed either diets sufficient (300 ppm) or insufficient (5 ppm) in iron for 10 weeks. The iron-deficient animals had lowered hemoglobin and hematocrit levels and higher levels of kidney lysozyme activity than did control animals. There were no significant changes in serum and spleen lysozyme activity levels.     

The influence of salt intake on glomerular count in compensatory kidney hypertrophy in rats of different ages

Summary Drinking saline instead of water elevated the glomerular count in hypertrophied kidneys of rats uninephrectomized as adults. No changes occurred in glomerular concentration in kideny tissue indicating a more marked increase of other kidney structures. This procedure was ineffective in immature animals.     

Fehlen einer cancerogenen Wirkung von nitrosen Gasen beim Goldhamster

Summary Continuous exposure of golden hamsters to nitrous fumes (40 ppm NO₂+20 ppm NO) for up to 16 months revealed no carcinogenic action of nitrogen oxides in the lung nor in other organs.     

Lysozyme levels in tissues of iron-deficient rats

Summary Rats were fed either diets sufficient (300 ppm) or insufficient (5 ppm) in iron for 10 weeks. The iron-deficient animals had lowered hemoglobin and hematocrit levels and higher levels of kidney lysozyme activity than did control animals. There were no significant changes in serum and spleen lysozyme activity levels.Supported in part by grant HL18712-02, Heart and Lung Institute, NIH.     

On the use of phosphamidon for eradication of fresh water fish predators

Zusammenfassung Laboratoriumsexperimente mit Phosphamidon ergeben eine günstige kritische Dosisempfindlichkeit für Labeo-Karpfen (150–250 ppm). Es gelingt so leicht, Wasserinsekten (2–10 ppm) und Raubfischstadien (20–125 ppm) aus den Frischwasserreservoiren zu eliminieren.

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Prepared and sold under the name of Dimecron 100 by Ciba Basel, (Switzerland).     

Force development in smooth muscle strips of the hypertrophied urinary bladder of the rat after autonomic decentralization

Summary Active length-tension relations for muscle strips of decentralized bladders differed from those of controls when comparisons were based on length in situ, but not when comparisons were based on lengths relative to optimum lenght for force development. The decentralized bladder behaved similarly to the denervated bladder, thus indicating that the presence of nerves was of no importance for the force production of directly stimulated muscle cells in the hypertrophied bladder.This work was supported by grants from the Swedish Medical Research Council (B82-14X-05927-02 and B82-14X-00028-18) and the Medical Faculty of Lund.