Karyotypes of seven species of bats from Thailand (Chiroptera, Mammalia)

Karyotypes of Myotis siligorensis, Myotis mystacinus, Pipistrellus pulveratus, Tylonycteris robustula, Miniopterus schreibersi fuliginosus, Hipposideros fulvus and Aselliscus stoliczkanus from Thailand are investigated.     

Serologisch-hämatologische und immunologische Untersuchungen an winterschlafenden Fledermäusen (Myotis myotis S.)

Summary Antibody deficiency in hibernating bats (Myotis myotis S.) was shown by precipitin reaction. The-globulins in serum of hibernating bats decreased to one half of the normal value. There is significant leukopenia, lymphopenia and eosinopenia. Injected bovine albumin was completely removed within 9 days in active animals, in torpid animals only 1/25 was absorbed from the 6th to the 23rd day.     

Aktivitätsuntersuchungen bei Fransenfledermäusen (Myotis nattereri,Kuhl 1818)

Summary Field experiments on the diurnal activity of Natterer's bat (Myotis nattereri, Kuhl 1818) are described. The diurnal activity pattern follows the course of the light intensity with a phase difference. This phase difference and certain details of the activity pattern are subject to seasonal changes and are influenced by the ambient temperature.     

Mast cells and hibernation: Observations in the Indiana bat,Myotis sodalis

Zusammenfassung Untersuchungen über die Zahl der Mastzellen und den Histamingehalt in Gewebe der Indiana-FledermausMyotis sodalis während des Winterschlafes zeigten keine Unterschiede zwischen den im Herbst, Winter und Frühling getöteten Tieren.     

Calcium and phosphate levels in bats (Myotis lucifugus) as function of season and activity

Zusammenfassung Untersuchungen an Laboratoriums-FledermäusenMyotis lucifugus während aller Phasen der Winterschlaflethargie zeigen, dass Unbeweglichkeit der Tiere entscheidend auf den Verlust an Knochenmineralien wirkt. Die Vermehrung an Osteoklasten sowie die Hyperkalzemie und die Hypophosphatemie bei winterschlafenden Fledermäusen weisen ebenfalls in Richtung der Resorptionsvorgänge im Knochen.     

Development of DNA probes for cytotoxin and enterotoxin genes in enteric bacteria

Summary DNA probes to identify the genes encoding toxins in enteric bacteria have been developed. Use of these probes reduces the number of animals required for toxicity testing, as suspect bacteria can be directly tested for the presence of toxin. We have augmented the gene probes available by developing probes against theEscherichia coli enterotoxin LTII and shiga toxin fromShigella dysenteriae 1.The LTII gene fromE. coli 357900 was identified and characterised and a suitable internal probe was obtained. The LTII gene was found not to be common among enterobacteriae from various geographical locations. Isolates predominately of animal origin from Nigeria and Thailand hybridized with the probe.The shiga toxin gene was isolated fromS. dysenteriae 1 by a combination of in vivo and in vitro methods. An internal probe was identified and used against different serogroups ofShigella andE. coli isolated. The probe was found to hybridize withS. dysenteriae 1 isolates and also someS. flexneri andS. sonnei strains. Representatives were tested for toxin production and found to produce toxin at low levels.     

La formule chromosomique chez cinq espèces de Chiroptères

Summary Five species ofChiroptera were studied and the following numbers were found:Rhinolophus hipposideros Bechst.N=27;Barbastella barbastellus Schr.N=16;Plecotus auritus L.N=16;Myotis myotis Bork.N=21;Miniopterus schreibersii Kuhl,N=23. Centric fusions occur in the chromosomal evolution ofChiroptera. Sex-chromosomes ofX-Y type.     

Die mit Hilfe der Beringungsmethode erzielten Ergebnisse über Lebensdauer und jährliche Verlustziffern beiMyotis myotis Borkh

Summary (1) The greatest age ofMyotis myotis hitherto ascertained by means of the marking method, is 12 years.(2) The annual loss, observed with striking regularity, amounts to 40%.(3) It is remarkable that in the first years of control the number of losses of females is far higher than that of males. This observation coincides with the ascertained fact that the reported number of females found dead is nearly double the corresponding number of males.(4) According to the notifications of dead animals found the months most rich losses are May and June. Evidently the females are particularly exposed to peril by the development of the embryo which takes place at that time, and by the breeding of their young ones.     

Quenching of intrinsic fluorescence accompanies the activation of prococoonase

Summary The intrinsic fluorescence of prococoonase fromBombyx mori is largely quenched upon its activation. The rates of fluorescence quenching and enzyme activation are equal, indicating that both reflect the same process.This work was supported by a grant from the National Research Council of Thailand.     

Binding of antimalarial drugs to hemozoin fromPlasmodium berghei

Summary Chloroquine, quinacrine and mefloquine bind toPlasmodium berghei hemozoin, hemin, heme, protoporphyrin IX and protease digested methemoglobin. This binding may be the basis for drug accumulation and action in the parasite.Acknowledgments. We thank the World Health Organization, the National Research Council of Thailand and Mahidol University for financial support. Dr Prapin Wilairat's suggestions are appreciated.     

Ansamitocin P-3, a maytansinoid,fromClaopodium crispifolium andAnomodon attenuatus or associated actinomycetes

Summary Guided by cytotoxicity, ansamitocin P-3, a maytansinoid, was isolated in very low yield from two members of the moss family Thuidiaceae,Claopodium crispifolium (Hook.) Ren & Card. andAnomodon attenuatus (Hedw.) Hueb. Ansamitocin P-3 showed potent cytotoxicity against the human solid tumor cell lines A-549, HT-29. A possible basis for the occurrence of this compound in mosses is discussed.Presented at the XV International Symposium on Natural Product Chemistry, Monterrey (Mexico) April 28–30, 1988 and at the International Research Congress on Natural Products, Park City (Utah, USA) in July 1988.Acknowledgments. This work was supported by grant No. CA 33326 from the NCI, NIH, USA. K.S. is the recipient of support from the Anandha-Mahidol Foundation, Thailand. The 470 MHz NMR instrument was available through the Purdue University Biochemical Magnetic Resonance Laboratory supported by NIH grant No. RR1077 from the Biotechnology Resources Program of the Division of Research Resources. Special thanks are due to the Purdue Cell Culture Laboratory for in vitro testing data and to Dr M. Antoun forC. crispifolium extraction. The animal testing data are the results of screening performed under the auspices of the Developmental Therapeutics Program, Division of Cancer Treatment, the NCI.     

Body temperature cycling of winter little brown bats in the cold following heat exposure

Zusammenfassung Kleine braune Fledermäuse,Myse, Myotis lucifugus, wurden dem Winterschlaf entzogen und eiund einer neutralen Temperatur von 33°C während 0–48 Tagen agen ausgesetzt und darauf drei Tage lang 10°C. Bei Fledermäuermäusen, welche Kälte (10°C) ausgesetzt waren, erwies die To die Temperaturkurve im allgemeinen, dass das Verhältnis altnis und das Ausmass des Erwachens sowie die Regelungelung der Tätigkeit oder Körpertemperatur proportional mital mit der Dauer abnahmen, während welcher sie der Hitze (33tze (33°C) ausgesetzt waren.

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This investigation was supported by the National Institutes of Health Grant GM-10811 and the Purdue Research Foundation X-R Grant 3269.     

Structure and assembly of the 20S proteasome

The barrel-shaped 20S proteasome is one of the two components of a larger 26S particle, the multicatalytic 2000-kDa protease complex. The proteolytic sites are located in the inner chamber of the 20S particle and are only accessible via narrow entrances. This paper reviews the current knowledge concerning proteasome formation, proteolytic activities, structural aspects and assembly. Eukaryotic proteasomes are made up by four rings each of which contains seven different subunits occurring at fixed positions. While the outer rings contain α-type subunits, the inner ones comprise β-type subunits. The current assembly model for eukaryotic 20S proteasomes is based upon the detection of 13S and 16S intermediates, respectively, in addition to previous findings with archaebacterial and eubacterial proteasome assembly. The available data suggest a cooperative assembly of the α-type and β-type subunits into half proteasome-like complexes followed by dimerization into proteasomes. During or after dimerization of half proteasomes, the β-type subunits are processed. The prosequence of the β-type subunits is essential for the assembly process and prevents protease activity of immature proteasomes.     

La formule chromosomique deSorex minutus L. (Mammalia-Insectivora)

Summary The chromosome complement ofSorex minutus L. has been determined. The caryotype is characterized by a diploid number of 42 and by aNF (fundamental number) of 56. The sex-chromosomes are of theX−Y type usual in mammals. The origin and the evolution of the chromosome set ofS. minutus, S. unguiculatus, andS. araneus have been discussed.      

Distribution of 5 S RNA in the liver of the South American rattlesnake,Crotalus durissus terrificus

Résumé Nous avons étudié la distribution du RNA 5S dans le foie du serpent sud-américainCrotalus durissus terrificus. Nos résultats ont montré que le RNA 5S de ce reptile est associé à la sous-unité ribosomique 60 S. D'autre part, la mobilité electrophorétique de ce RNA de faible poids moléculaire est la même que celle d'Escherichia coli et de pupe d'Apis mellifera L.

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Acknowledgment. We are greatly indebted to Dr.T. Yamane for a supply of 5S RNA ofEscherichia coli.     

Robertsonian translocation,pericentric inversion and heterochromatin block in the evolution of the Tailless Fruit Bat

Summary The karyotype ofMegaerops ecaudatus from Peninsular Malaysia consists of 24 chromosomes as compared to 2n=26 for specimens from Thailand. The difference in diploid number is the result of Robertsonian translocation. The Peninsular Malaysian specimens also exhibit pericentric inversion in the smallest pair of autosomes, and the presence of a totally heterochromatic short arm in the second longest metacentric pair. There is 1 pair of Ag-NOR, located on the secondary constriction of the longest metacentric autosome.This work is supported by a University of Malaya research grant.     

Occurrence of carotid labyrinth in the catfish group of teleost fishes

Summary A structure similar in topography and morphology to the carotid labyrinth of amphibians has been found in 4 catfishes, namely,Clarias batrachus, Heteropneustes fossilis, Rita rita andMystus seenghala. The present finding of the presence of the carotid labyrinth in fishes is the first report, and the results are discussed in the light of the amphibious habit of these catfishes.We are grateful to Prof. U.S. Srivastava for providing laboratory facilities and for encouragement. The work was financially supported by the S.C.S.T., U.P. which is thankfully acknowledged.     

Mutagenic effect of UV-light and X-rays onStreptomyces nigrifaciens and yield of the antifungal substance

Résumé Changement de capacité de production antibiotique chez mutants nouveaux deStreptomyces nigrifaciens.

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Thanks are due to PrincipalS. Sinha of Agra College, Agra, for providing all facilities and to C.S.I.R., New Delhi, for award of research followship to S.G.     

The antimicrobial activity of some insect extracts possessing juvenile hormone activity

Zusammenfassung Extraktstoffe vonH. cecropia, S. cynthia undR. orizaba zeigten antibakterielle Wirkung gegenüber mehreren Mikroorganismen. Ein schwächerer Effekt wurde auch mit den Extraktstoffen vonGalleria mellonella, adulten Männchen vonCynthia- und vonCecropia-Puppen beobachtet. Die antimikrobielle Aktivität wurde mit dem Fettsäureanteil der Extraktstoffe in Beziehung gesetzt und von der Wirkung des Juvenilhormons abgegrenzt.

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Supported by Grants G-7597 from NSF and A-2818 from U.S.P.H.S.