Conformational mutations in human mitochondrial DNA

Variation in the human mitochondrial DNA (mtDNA) sequence has been extensively analysed using restriction fragment length polymorphisms (RFLPs). MtDNA RFLPs have previously been attributed to nucleotide changes within restriction endonuclease recognition sites or to small insertion-deletion mutations. We now report that RFLPs detected by polyacrylamide gel electrophoresis can also result from single nucleotide substitutions which alter the mobility of small- to medium-sized restriction fragments that incorporate the sequence. We have defined the mutation responsible at two loci and have identified several possible additional loci. When screening human mtDNAs with multiple restriction endonucleases, such mutations can be misidentified as insertion-deletion mutations or counted as multiple polymorphic restriction sites. This can lead to errors in constructing restriction maps and estimating sequence diversity.     

Peroxidase mediated oxidation of tyrosine: Tyrosine hydroxylation in tea leaves

Zusammenfassung Untersuchungen über die Beeinflussung der Tyrosinhydroxylierung durch Peroxidase in Teeblättern (Camellia sinensis L.) mit Hilfe von Antooxydantien.     

Effect of butyl alcohol inDatura innoxia Mill

Zusammenfassung Die Behandlung der Samen vonDatura innoxia Mill. mitn-Butylalkohol und Temperaturschock ergibt in der nächsten Generation Pflanzen, deren Samen einen höheren Alkaloidgehalt aufweisen. Das Hauptalkaloid ist Scopolamin (Hyoscin) mit einem Anteil von 50–70% am Gesamtalkaloidgehalt.

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The author is grateful to Dr. K.Ganapathi, Director, and Dr. C. K.Atal, Scientist of this Laboratory, for their interest in the work.Shri Het Singh, Dr. K. L.Dhar and MissSubash Kumari helped by analyzing the seeds which is duly acknowledged.     

Effect of nerve stimulation on rat skeletal muscle. A study of plasma membrane

The gastrocnemius muscle of the rat showed no morphological, histometric or plasma membrane changes, after sciatic nerve stimulation with a 5mA current for 30 to 60 min, 10 mA for 30 min and 15 mA for 5 min. However, 10 mA for 60 and 200 min gave rise to mitochondrial and plasma membrane abnormalities. These changes were absent after a rest period. The results indicated that the sciatic nerve stimulation at 10 mA for 60 and 200 min caused reversible changes in the rat skeletal muscle mitochondria and plasma membrane.     

An analytical study of the neurosecretory cells of the brain inPhilosamia ricini (Hutt.) (Lepidoptera: Saturniidae) during post-embryonic development

Summary A multiplicity of types of neurosecretory cell (NSC), and uniformity in the numbers occurring in medial, lateral, posterior and tritocerebral groups, have been observed inP. ricini. 3 types of cells A, B and C, with their subtypes (A-1, A-2, A-3; B-1, B-2; C-1 and C-2) have been reported. Only B-cells increase in numbers during post-embryonic development. Others (A and C) remain constant throughout development. Abnormal staining behaviour of A-cells has also been reported.Acknowledgements. We are grateful to Prof. S.D. Misra for the facilities and to the UGC, New Delhi, for sanctioning a grant No. F. 23-781/78 (SR II) dated 27.4.78 to Dr V.B. Awasthi, which is gratefully acknowledged.     

New non-photodynamic (type B) phototoxic molecules

Summary This report completes the examination of the 3 butadiynes substituted with phenyl and thienyl groups, and their related thiophene molecules. With the exception of 2,5-diphenylthiophene, they are all non-photodynamic (type B) phototoxic compounds.Acknowledgments. We are grateful to the National Institutes of Health for the support of this research (GM 24144).