Effect of methyl ester of aristolic acid fromAristolochia indica Linn. on fertility of female mice

Summary Methyl ester of aristolic acid, a pure compound isolated from the roots ofAristolochia indica (Linn.), was found to exert 100% abortifacient activity at a single oral dose of 60 mg/kg b. wt when administered on 6th or 7th day of pregnancy; 20 and 25% abortifacient effect were observed at the same dose on day 10 and 12, respectively.The authors wish to thank Dr S.C. Pakrashi and his associate Mr P.P. Ghosh Dastidar for the compound. Thanks are also due to the Director General of Indian Council of Medical Research for granting a fellowship to one of them (C.S.).     

Effect of the extracts fromAristolochia indica Linn. on interception in female mice

Summary The crude petroleum ether, chloroform and alcoholic extracts of the roots ofAristolochia indica (Linn.) showed 100% interceptive activity in mature female mice at the single dose of 100 mg/kg body wt. The follow-up studies with the chloroform extract showed the most significant effect in the basic part and two acidic fractions at the single dose levels of 50 mg/kg body wt. No toxic effect was observed at the dose levels used.The authors are thankful to Mr.P. P. Ghosh Dastidar, Medicinal Chemistry Division for the plant extracts. Thanks are also due to Indian Council of Medical Research and Council of Scientific and Industrial Research for granting scholarships to two of them (B.C. and A.D.) and to Prof.R. N. Chakravarti, Director of the Institute for encouragement.     

A fungitoxic principle from the leaves ofLawsonia inermis Lam.

Summary During antifungal screening of higher plants, the leaves ofLawsonia inermis were found to exhibit strong fungitoxicity. On chemical investigation, the antifungal factor was found to be 2-hydroxy-1,4-naphthoquinone (Lawsone). The minimum effective dose against test organism was found to be 1000 ppm. Lawsone was found to exhibit fungicidal activity, wide fungitoxic spectrum and nonphytotoxicity.Acknowledgment. Authors are thankful to Dr Nitya Nand, Central Drug Research Institute, Lucknow, for providing facilities to carry out chemical investigations. Our thanks are particularly due to Dr R. S. Kapil, Dr Geeta Devi Tripathi and Dr S. C. Tripathi for their help rendered in various ways.     

Effect of p-coumaric acid on immature estrogen treated and cyclic female mice

Summary Oral administration of p-coumaric acid to estrogen-primed immature female mice exerts neither estrogenic nor anti-estrogenic activity, but when it is administered to cyclic female mice in single dose at proestrus or in repeated doses, induces alteration in estrus cycle, ovarian and uterine weight and structure.The authors wish to thank Dr S. C. Pakrashi and his associates of Medicinal Chemistry Department for isolating the compound. Thanks are also due for granting Senior Research Fellowship to P.P. and Junior Research Fellowship to S.N.K. respectively.     

Laccase production byPolyporus sanguineus under different nutritional and environmental conditions

Summary Laccase production was higher in malt extract medium than in lignin, andPolyporus sanguineus appears to be better thanPolyporus versicolor andTrametes hirsuta (syn.Polyporus hirsutus) for enzyme production. Phenolic compounds, of which resorcinol was the most active, induced enzyme production; while sugars repressed it. A temperature of 37°C, pH 3 and indulin AT at a concentration of 0.2% gave the best enzyme yield.A part of Ph. D. thesis of D.S. Arora.Acknowledgments. We thank Westvaco Chemical Division, USA, and Dr P.S. Rehill, Forest Research Institute, Dehradun, India for providing lignin samples and the fungal strain, respectively. D.S. Arora further thanks University Grants Commission, New Delhi for financial assistance.     

Mitosis in the haemocytes ofSarcophaga ruficornis (diptera)

Summary Among the haemocytes ofSarcophaga ruficornis, only the prohaemocytes divide. Injection of phytohaemagglutinin-P induces 100% prohaemocytes to undergo mitosis but does not induce mitosis in other cells. Mitotic stages other than the prophase are apparently very short lived.Acknowledgment. We express our gratitude to the State Council of Scientific and Industrial Research, U.P. for the grant of financial assistance to U.S.S.     

Effect of the juvenoid methoprene on the hemolymph composition of the cabbage maggotDelia radicum (Diptera: Anthomyiidae)

Summary Treatment of post-feeding larvae of the cabbage maggotDelia radicum with methoprene did not affect the capacity of the insect to pupate, but suppressed eclosion to the adult stage. The concentration of hemolymph trehalose was significantly decreased by methoprene treatment, although hemolymph protein and amino nitrogen levels were unaffected.19 December 1986The authors are grateful to D. C. Read of the Research Centre, Agriculture Canada, Charlottetown, P.E.I., Canada for supplying eggs ofD. radicum for the stock colony. TheD. radicum colony was maintained at the Agriculture Canada Research Station, St. John's West, Newfoundland, Canada. The sample of methoprene was donated by Zoecon Corp., Palo Alto, California, U.S.A. This research was supported by a grant from the Natural Sciences and Engineering Research Council of Canada (Operating grant A6679).     

Temperature dependence of neurotransmitter release in the antarctic fishPagothenia borchgrevinki

Summary The quantal contents of endplate potentials from extraocular muscles of an antarctic fishPagothenia borchgrevinki were measured over a range of temperatures. Quantal release was maximal at about 5°C but showed little dependence on temperature between –2°C and 10°C. Above 10°C quantal content declined until release ceased about 18°C. In view of the fact that the ambient temperature at which these fish live is constant at –1.9°C, the results suggest thatPagothenia borchgrevinki is only partially adapted to its environment despite 25 million years acclimatization.The authors wish to thank the staff of New Zealand's Scott Base, Antarctica, without whose cooperation the work would have been impossible. Mr J. Quinn of the Auckland University Physiology Department gave invaluable assistance with computing and electronics and the Antarctic Division of the New Zealand Department of Scientific and Industrial Research provided transportation and logistic support. The project was financially supported by the New Zealand University Grants Committee and the Auckland University Research Committee. S.P. was a Senior Fellow of the N.Z. Medical Research Council.     

Histochemical localization of alkaline and acid phosphatase activities in the skin ofMystus (Mystus) vittatus Bl. (Siluriformes)

Summary An attempt has been made to localize alkaline and acid phosphatase activities in the skin ofMystus vittatus by using histochemical techniques. The alkaline phosphatase activity is found in metabolically active cells such as basal columnar cells, mucous cells and polygonal support cells. The acid phosphatase activity is intense in the outermost squamous support cells and in the basal columnar cells. These activities have been correlated with some physiological functions of the epidermis.Acknowledgment. We are thankful to P. Vishwanatham, Government College, Mhow, and Dr R.S. Shrivastava, Holkar Science College, Indore, for providing laboratory facilities and to the Council of Scientific and Industrial Research, New Delhi, for a fellowship for M.S.     

The generation of toxic activity fromTrypanosoma congolense

Summary Trypanosoma congolense organisms, on incubation at 20°C for 91/2h, were found to generate phospholipaselike activity which was capable of mediating lysis of both nucleated cells and erythrocytes as well as an acute inflammatory response on intradermal inoculation.Acknowledgments. This investigation was supported by the International Development Research Centre.     

Electrical response of bat retina to spectral stimulation: comparison of four microchiropteran species

Summary Electrical responses of the retinas of 4 species of microchiropteran bats stimulated by spectrally restricted light flashes were found to diverge systematically from the rhodopsin absorption spectrum. The divergence was progressively greater across the 4 species. The results appeared explainable by assuming a second photoreceptor class and photopigment which was present in progressively greater numbers in the retinas ofEptesicus fuscus, Desmodus rotundus, Artibeus jamaicensis andCarollia perspicillata.This work was made possible by equipment provided by grant No. EY 01228 from the U.S.P.H.S., Bob Hope Fight for Sight award No. G 522 and a grant from Research to Prevent Blindness, Inc. Portions of this work were presented at the Fifth International Bat Research Conference, Albuquerque, New Mexico, August 11, 1978.The authors would like to express appreciation to Drs A.M. Potts, J. B. Longley, R. S. Crockett and T. G. Wheeler for helpful suggestions and to Drs J. H. Richardson, J. G. Cooper, L. Kundrotas, Mr B. Spoonamore and Mr W. Lopez-Forment for facilitating collection and importation of the Mexican bats.     

Telocentric chromosomes in pearl millet,Pennisetum typhoides

Summary InPennisetum typhoides S. and H., a new karyotype was found with 13 normal chromosomes and 2 stable telocentric chromosomes, which represent 1 arm each of a submetacentric chromosome.The authors are thankful to Dr.J. V. Pantulu, Professor of Cytogenetics, for guidance and encouragement and to Dr.V. Manga, for helpful discussion. They express their thanks to the U. G. C. (PSRLNR) and to the C. S. I. R. (MVSR and INR) for the award of Junior Research Fellowships.     

Functional interaction between TRPC1 channel and connexin-43 protein: a novel pathway underlying S1P action on skeletal myogenesis

We recently demonstrated that skeletal muscle differentiation induced by sphingosine 1-phosphate (S1P) requires gap junctions and transient receptor potential canonical 1 (TRPC1) channels. Here, we searched for the signaling pathway linking the channel activity with Cx43 expression/function, investigating the involvement of the Ca²⁺-sensitive protease, m-calpain, and its targets in S1P-induced C2C12 myoblast differentiation. Gene silencing and pharmacological inhibition of TRPC1 significantly reduced Cx43 up-regulation and Cx43/cytoskeletal interaction elicited by S1P. TRPC1-dependent functions were also required for the transient increase of m-calpain activity/expression and the subsequent decrease of PKCα levels. Remarkably, Cx43 expression in S1P-treated myoblasts was reduced by m-calpain-siRNA and enhanced by pharmacological inhibition of classical PKCs, stressing the relevance for calpain/PKCα axis in Cx43 protein remodeling. The contribution of this pathway in myogenesis was also investigated. In conclusion, these findings provide novel mechanisms by which S1P regulates myoblast differentiation and offer interesting therapeutic options to improve skeletal muscle regeneration.     

Low ambient oxygen tolerance in some freshwater teleosts

Summary Measurements of the asphyxial oxygen level forRhinomugil corsula, Tilapia mossambica, Puntius sarana andCarassius auratus at 30 and 35°C revealed that at 35°C the lethal oxygen level was higher forT. mossambica andP. sarana and lower forR. corsula, but it remained the same forC. auratus at 30 and 35°C. From a thesis (M.P.M.) approved for the degree of Doctor of Philosophy, Madurai Kamaraj University, madurai, India. We wish to express our thanks to Prof. S. Krishnaswamy for providing facilities and to Dr S.V. Job for suggestions.     

High affinity of quinidine for a stereoselective microsomal binding site as determined by a radioreceptor assay

Summary The techniques of the radioreceptor binding assay were applied to detect stereoselective binding of quinidine and quinine to a site on human liver microsomes. Binding of³H-dihydroquinidine was 50% inhibited by 20–100 nM quinidine, while its enantiomer quinine did not displace the³H-ligand at concentrations up to 500 nM. This stereoselectivity agreed with the affinity values measured by functional enzyme assays of cytochrome P450 activity using sparteine or debrisoquine as substrates.Acknowledgments. We thank C. Ulpian for advice and assistance. We also thank Dr M. Robinette of Metro Organ Retrieval and Exchange and Dr T. Inaba for making human hepatic tissue available. This work was supported by grants from the Medical Research Council of Canada.     

A cold-active salmon goose-type lysozyme with high heat tolerance

The Atlantic salmon (Salmo salar) goose-type lysozyme gene was isolated and revealed alternative splicing within exon 2 affecting the signal peptide-encoding region. The lysozyme was produced in Escherichia coli, and the recombinant enzyme showed a high specific lytic activity that was stimulated by low or moderate concentrations of mono- or divalent cations. Relative lytic activities of 70 and 100% were measured at 4°C and 22°C, respectively, and there was no detectable activity at 60°C. However, 30% activity was retained after heating the enzyme for 3 h at 90°C. This unique combination of thermal properties was surprising since the salmon goose-type lysozyme contains no cysteines for protein structure stabilization through disulphide bond formation. The results point to a rapid reversal of inactivation, probably due to instant protein refolding. Received 14 August 2007; received after revision 07 September 2007; accepted 12 September 2007     

Reduced carbonic anhydrase and Na−K-ATPase activity in gills of salmonids exposed to aluminium-containing acid water

Summary Exposure of young specimens ofS. salar andS. gairdneri to aluminium concentrations of 200 g/l in water at pH 5 induced reductions of 25–40% in the activity of carbonic anhydrase and Na–K-ATPase in the gills.Fish were generously supplied by Settefiskanlegget A/S, Lundamo and the Research Station for Salmonids, Sunndalsøra.     

Enantiomeric cannabinoids: stereospecificity of psychotropic activity

Summary The 1,1-dimethylheptyl homolog of (–)-(3R,4R)-7-hydroxy-delta-6-tetrahydrocannabinol (compoundII) is highly psychotropic in mice, rats and pigeons. The (+)-(3S,4S) enantiomer (III) was found to be psychotropically inactive at doses up to several thousand times those of the ED₅₀ of (II).We thank Dr A. Breuer and Mrs H. Amsalem for help with the syntheses. The research reported above was supported in Tucson by NIH grant NS 15441; in Uppsala by grants from the Swedish Medical Research Council (5757) and the Swedish Council for the Planning and Coordination of Research (84/2082); in Jerusalem by the Szold Foundation.Presented in part at a meeting at the US National Institute on Drug Abuse, Washington, D.C., October 1986, see NIDA Research Monographs79 (1987) 15.     

A highly active glutathione peroxidase in red blood cells of normal and acatalasemic mice

Summary The activities of catalase (E.C.1.11.1.6) and glutathione peroxidase (E.C.1.11.1.9) were compared in red blood cells from humans, ducks and normal and acatalasemic mice. In the cells from both strains of mice, an equally high activity of GSH-Px was found which could be inhibited completely by iodoacetate but was not sensitive to N-ethylmaleimide.Acknowledgment. This work was supported by a postdoctoral fellowship from the Gesellschaft für Strahlen- und Umwelt-forschung, München, Federal Republic of Germany, and was performed under contract with the U. S. Energy Research and Development Administration at the University of Rochester Biomedical and Environmental Research Project and has been assigned Report. No. UR-3490-1138.     

A study on the parameters of digestion inPeriplaneta americana L

Summary An attempt was made to provide evidence for the regulatory mechanism for digestion inPeriplaneta americana by studying possible correlations between digestive enzymes, taking midgut protease activity into considerationI wish to acknowledge Prof. J. Bahadur, Jiwaji University, Gwalior, India, for his supervision, criticism and encouragement during the course of this study. Award of Junior Research Fellowship by C.S.I.R., New Delhi is also thankfully acknowledged.