Photoperiod-induced changes in temperature-metabolism curve,shivering threshold and body temperature in the pigeon

Summary A short photphase combined with cold-acclimation changed the shivering threshold of the pigeon from 21 to 14 °C. The change of critical temperature was also found in the temperature-metabolism curve. A long photophase both alone and combined with warm-acclimation induced a reduction of body temperature to a lower level (about 2°C) at all ambient temperatures, ranging from 5 40°C.     

Central course of photic input in the ventral nerve cord of scorpion (Heterometrus fulvipes)

Summary The course of the photic input from the metasoma in the ventral nerve cord of scorpion was studied. The input was found to influence the activity in a large number of neurons in the nerve cord. The phenomenon of contralateral stimulation of units at various levels of the nerve cord has heen demonstrated.Acknowledgments. The electronic equipment used for the study was obtained with the help of Prof.T. H. Bullock and the late Prof.K. Pampapathi Rao who initiated me into this field of study, through a research grant from the USAFOSR to them. I am highly grateful to Prof.Bullock for permitting me to use the equipment. I am also grateful to Dr.A. R. Kasturi Bai for her kind encouragement and Dr.S. A. T. Venkatachari for his helpful comments.     

Heat evolution of cultured human keratinocytes

Summary The heat production of normal and transformed human epidermal keratinocytes precultured in Petriperm ^tm tissue culture dishes was measured calorimetrically. For this purpose, the membrane at the bottom of the culture dish was cut out aseptically and put into a microcalorimeter vessel with the cell layer inwards. A continuous heat output of (83±12) pW/cell was measured for normal keratinocytes from a confluent primary culture. A value of (134±35) pW/cell was obtained when the transformed kerationocyte line SV-K14 was used. The method described in this paper is simple, leads to reproducible results, and can be easily adapted to the calorimetric study of other mammalian cells in vitro.     

Estrogen-induced uterine metaplasia in rats given oral supplements of vitamin A

Zusammenfassung An der Ratte wurde der Einfluss von oral verabreichtem Vitamin A auf die östrogeninduzierte Metaplasie der Uterusschleimhaut untersucht. Kleine Dosen von Vitamin A (250 IE pro Woche) sind zur Vermeidung dieser Metaplasie wirksamer als grosse Dosen von Vitamin A (100 000 IE pro Woche).

---

---

This research was completed while the author was a student in the Department of Anatomy, Bowman Gray School of Medicine, Winston-Salem, N.C. It was supported by a grant from the National Vitamin Foundation. The author is indebted to Dr. W. J. Bo for suggesting the problem and for making himself available for consultation.     

Phenobarbital and SKF-525A on vinblastine and vincristine toxicity in mice

Summary The effect of SKF-525A and phenobarbirtal on the LD₅₀ values of vinblastine and vincristine suggests that the toxicity of these agents in mice does not arise from a toxic metabolite.This work was supported by PHS Grant No. GM 15956. The author wishes to thankMary-Lucille Mantz for her valuable technical assistance and the Eli Lilly Company for graciously providing generous samples of VLB and VCR. The ample gift of SKF-525A from Smith, Kline and French Laboratories is also gratefully acknowledged.     

Formation of 4-ketocyclophosphamide by the oxidation of cyclophosphamide with KMnO4

Zusammenfassung Oxydation des (³²P) Cyclophosphamides durch KMnO₄ in Wasser oder Aceton führt zu 4-Ketocyclophosphamid und einem N-dechloroäthylierten Derivat des Cyclophosphamides, beides bekannte Metaboliten der Droge. Die Auftrennung der Produkte gelingt durch Dünnschichtchromatographie und die Richtigkeit der Strukturen wurde durch Massenspectrometrie nachgewiesen.

---

---

Acknowledgments. This investigation was supported by grants to the Chester Beatty Research Institute (Institute of Cancer Research: Royal Cancer Hospital) from the Medical Research Council and Cancer Research Campaign. The A.E.I. MS-12 mass spectrometer was purchased on a special grant No. G969/189/C from the Medical Research Council. The work was carried out partly during the tenure of a Ludwig Fellowship awarded by Cancer Research Institute. The interest of ProfessorA. B. Foster and Dr.T. A. Connors in this work, and the skilled technical assistance of Mr.M. H. Baker, are gratefully acknowledged.     

Preferential neurotoxicity of pentobarbital on nerve and glial cells in culture

Summary The effect of pentobarbital was studied in a mixed population of nerve and glial cells dissociated from brains of 7-day chick embryos and maintained in culture. Pentobarbital-Na was added in various concentrations ranging from 5×10^–5 M to 1×10^–3 M. The neuronal density was monitored by counting of neurons, neuronal identity was established by staining for Nissl Bodies and acetylcholinesterase. Over a culture period of 3 weeks, it was found that the barbiturate exerts a preferential dose-dependent cytotoxic effect on neurons.The expert technical assistance of Miss A. Wolf is appreciated. This work was supported by grant 6-74-27, INSERM (Physiologie et Pathologie du Développement Nerveux).     

9-Methyl-7-bromoeudistomin D,a potent inducer of calcium release from sarcoplasmic reticulum of skeletal muscle

Summary The Ca²⁺-releasing action of several derivatives of eudistomin D isolated from a marine tunicate was compared with that of caffeine. It was found that 9-methyl-7-bromoeudistomin D was approximately 1000 times more potent than caffeine in causing Ca²⁺ release from the sarcoplasmic reticulum.The authors thank Ms A. Muroyama of this institute for her technical assistance and Prof. K. L. Rinehart of University of Illinois for his encouragement.     

A cyanoglucoside stored by aSedum-feeding Apollo butterfly,Parnassius phoebus

A bitter tasting cyanoglucoside, sarmentosin, was isolated from an aposematic Apollo butterfly,Parnassius phoebus, and from its plant-host,Sedum stenopetalum. The content of sarmentosin in the body tissues was as high as 500 g/insect, suggesting a defensive role for this substance; a high concentration was detected in the wings. Sarmentosin was also present in the eggs.     

Immunosuppressive effect of a mouse placenta fraction on H-2 incompatible split heart allografts

Summary A soluble placenta fraction from mice (A.CA) mated with H-2 histoincompatible males (A/Sn) significantly prolonged the survival of heterotopic A/Sn heart transplants in A.CA recipients. No prolongation of A/Sn heart graft survival was obtained with the corresponding A.CA placenta fraction after A.CA × A.CA mating.The work was supported by the Danish Medical Research Council (Project No. 512-3088).     

Occurrence of tetrodotoxin in the starfishAstropecten latespinosus

Summary A toxin causing paralysis was detected in the starfishAstropecten latespinosus. The toxin was purified by a method consisting of charcoal treatment and chromatography on CM-Sephadex C-25 and Bio-Rex 70. The toxin was identified as tetrodotoxin by its behavior in thin-layer chromatography and electrophoresis and its¹H-NMR spectrum.Acknowledgment. This work was in part supported by a research fund from the Ministry of Agriculture, Forestry and Fisheries of Japan.     

Inhibitory effect of halocyamine,an antimicrobial substance from ascidian hemocytes,on the growth of fish viruses and marine bacteria

Summary Halocyamine A, an antimicrobial substance isolated from hemocytes of the solitary ascidianHalocynthia roretzi, inhibited in vitro the growth of fish RNA viruses (infectious hematopoietic necrosis virus and infectious pancreatic necrosis virus). Pretreatment of RNA virus with halocyamine A reduced the infectivity of the virus toward host cells. The growth of marine bacteria,Achromobacter aquamarinus andPseudomonas perfectomarinus, was also inhibited by halocyamine A but that ofAlteromonas putrefaciens andVibrio anguillarum was not. These results suggest that halocyamine may have a role in the defense mechanisms ofH. roretzi against marine viruses and bacteria.     

Accumulation of3H-dopamine by synaptic vesicles from rat striatum in an impermeant medium

Summary The accumulation of³H-dopamine by synaptic vesicles from rat striatum was significantly stabilized in a membrane impermeant medium. The characteristics of dopamine accumulation by striatal vesicles were quite similar to those reported for dopamine accumulation by a whole brain vesicle preparation in the same medium, and were siginificantly different from the characteristics previously reported for vesicular accumulation of norepinephrine.Acknowledgments. This work was supported by grant NS 18752 (NIH) of the United States Public Health Service. Reprint requests to J. A. R.     

Polyclinal,a new sulfated polyhydroxy benzaldehyde from the marine ascidianPolyclinum planum

Summary A new sulfated polyhydroxy benzaldehyde has been isolated from extracts of the temperate colonial ascidianPolyclinum planum. The structure of the new metabolite was solved by an X-ray crystallographic study. The highest concentration of this metabolite was found in the zooid-rich outer layers of this ascidian suggesting that it may represent a potential chemical defense against predators.     

Catestatin, an endogenous Chromogranin A-derived peptide, inhibits in vitro growth of Plasmodium falciparum

Catestatin, an endogenous peptide derived from bovine chromogranin A, and its active domain cateslytin display powerful antimicrobial activities. We have tested the activities of catestatin and other related peptides on the growth of Plasmodium falciparum in vitro. Catestatin inhibits growth of the chloroquine-sensitive strain of P. falciparum 3D7, exhibiting 88% inhibition at 20 μM. A similar partial inhibition of parasite growth was observed for the chloroquine-resistant strain, 7G8 (64%,) and the multidrug-resistant strain, W2 (62%). In the presence of parasite-specific lactate dehydrogenase, a specific protein–protein interaction between catestatin and plasmepsin II precursor was demonstrated. In addition, catestatin partially inhibited the parasite-specific proteases plasmepsin in vitro. A specific interaction between catestatin and plasmepsins II and IV from P. falciparum and plasmepsin IV from the three remaining species of Plasmodium known to infect man was observed, suggesting a catestatin-induced reduction in availability of nutrients for protein synthesis in the parasite.     

Trisomy of the T6 translocation chromosome in the mouse

Résumé En utilisant le chromosome T6 pour des expériences de transplantations dans la souris, nous avons trouvé des cellules contenant 41 chromosomes et le trisomique pour le chromosome T6.

---

---

This work was supported by The Spastics Society, A.A.M. was in receipt of a grant from the Instituto de Alta Cultura, Portugal. Mr.L. Kelberman processed the photograph.     

Nonspecific reaction of a thiol:Protein disulfide oxidoreductase with the disulfide bonds of insulin

Summary A thiol:protein disulfide oxidoreductase from bovine liver was isolated after separation from protein disulfide isomerase. The enzyme, after activation (reduction) with glutathione, was reacted with stoichiometric amounts of insulin and the sulfhydryl groups of the partially reduced hormone were labeled with iodo (l-¹⁴C)acetamide. After separation of the insulin chains, the radioactivity was found in both the peptides, with a ratio A-chain/B-chain equal to 2/1.     

Red cell metabolism in red and grey kangaroos

Summary Glucose utilization, lactate production and glutathione regeneration were measured in the red blood cells of 2 species of Australian Marsupials, Eastern grey kangaroo (Macropus gigantus) and red kangaroo (Macropus rufus), and were found to be significantly lower in the red blood cells from grey than that of red kangaroos.The author wishes to thank Mrs T. Stephens, M. A. Gruca and A. Mulley for help in blood collection and laboratory work. This work was supported by a grant from the National Health and Medical Research Council of Australia.     

Effects of chronic lithium administration on concanavalin A binding to plasma membranes from the corpus striatum of rat brain

Summary The effects of chronic in vivo lithium administration on mannose-containing components of plasma membranes from rat corpus striatum were examined by a³H-concanavalin A binding displacement method. No difference in Con A binding was observed between sodium or lithium-treated rats during a 1-month period.We thank Dr S. Gershon of this research unit for his encouragement and support during these studies.     

Improved separation at low temperature of glycoproteins by Con A-Sepharose affinity chromatography in the presence of sodium dodecyl sulfate (SDS)

Summary The Con A-Sepharose affinity chromatography of glycoproteins was even more effective at 4°C than that at room temperature (26–28°C) in the presence of sodium dodecyl sulfate (SDS). Application of this methodology to the seperation of several glycoproteins from SDS-solubilized membrane proteins in rat cerebellum, including a glycoprotein characteristics of the Purkinje cells, was sucessful.Acknowledgments. A part of this research was supported by a Grantin-Aid for Scientific Research from the Ministry of Education, Science and Culture (No. 58480150), and also by a grant from National Center of Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare (No.83-11) in Japan.