Magnetic resonance microscopy: in vivo sectioning of a developing insect

Summary The utility of magnetic resonance imaging vis-a-vis insect morphology and development was investigated. MRI is a noninvasive technique that distinguishes between tissues based on proton content and proton environment. At present a resolution of 100 m is achievable. The technique avoids fixation artifacts and allows the detection of motion within the organism.     

Fourier analysis of vertebral shape change due to growth and selection for large and small body size

Summary Fourier analysis of videodigitised outlines of mouse vertebrae from two stocks, a pseudo-longitudinal series of mice aged 25–60 days and one selected for large or small body size over many generations shows that the shape changes due to normal growth are not similar to those produced by selection for body size.     

Influence of pinealectomy on serum estrogen and progesterone levels in blind-anosmic female rats

Summary Previous studies show that the suppression of gonadal function in blind-anosmic rats is dependent on the pineal gland. The present results demonstrate that in young female rats both the pineal gland and dual sensory deprivation have additional independent antigonaldal effects.This work was partially supported by state institutional funds and by NSF grant No. PCM 74-06276-276-A02. The radioimmunoassays of the steroids were carried out with the aid of the Radioimmunoassay Core which is supported by USPHS grant No. 1T30 HD-10202. We also thank Constance Stahl for typing assistance.     

Alkaloid studies XXV. The structure of the Aspidosperma alkaloids cylindrocarpine and cylindrocarpidine

Zusammenfassung Die Strukturaufklärung von Cylindrocarpin (II) und Cylindrocarpidin (IV) zeigt, dass diese zwei Alkaloide die ersten Mitglieder der Aspidosperminfamilie (I) sind, in denen eine sauerstoffhaltige Seitenkette anstatt der gewöhnlichen C-5-Äthylgruppe vorliegt.

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Paper XXIV,T. Nakano, C. Djerassi, R. A. Corral, andO. O. Orazi, J. org. Chem., in press.

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Postdoctorate research fellow, 1958–1960.     

Neurotransmitter receptors as glycoproteins

Summary Incubation of calf brain membrane preparations with the plant lectins, concanavalin A and wheat germ agglutinin did not inhibit neurotransmitter receptor binding sites directly. Plant lectins did however protect these sites against subsequent trypsin digestion suggesting that neurotransmitter binding sites may be associated with glycoprotein structures.     

A novel pantothenate kinase gene (PANK2) is defective in Hallervorden-Spatz syndrome

Hallervorden-Spatz syndrome (HSS) is an autosomal recessive neurodegenerative disorder associated with iron accumulation in the brain. Clinical features include extrapyramidal dysfunction, onset in childhood, and a relentlessly progressive course. Histologic study reveals iron deposits in the basal ganglia. In this respect, HSS may serve as a model for complex neurodegenerative diseases, such as Parkinson disease, Alzheimer disease, Huntington disease and human immunodeficiency virus (HIV) encephalopathy, in which pathologic accumulation of iron in the brain is also observed. Thus, understanding the biochemical defect in HSS may provide key insights into the regulation of iron metabolism and its perturbation in this and other neurodegenerative diseases. Here we show that HSS is caused by a defect in a novel pantothenate kinase gene and propose a mechanism for oxidative stress in the pathophysiology of the disease.     

Association of cadherin 23 with polygenic inheritance and genetic modification of sensorineural hearing loss

Age-related hearing loss (AHL) in common inbred mouse strains is a genetically complex quantitative trait. We found a synonymous single-nucleotide polymorphism in exon 7 of Cdh23 that shows significant association with AHL and the deafness modifier mdfw (modifer of deafwaddler). The hypomorphic Cdh23(753A) allele causes in-frame skipping of exon 7. Altered adhesion or reduced stability of CDH23 may confer susceptibility to AHL. Homozygosity at Cdh23(753A) or in combination with heterogeneous secondary factors is a primary determinant of AHL in mice.     

Lymphatic vascular defects promoted by Prox1 haploinsufficiency cause adult-onset obesity

Multiple organs cooperate to regulate appetite, metabolism, and glucose and fatty acid homeostasis. Here, we identified and characterized lymphatic vasculature dysfunction as a cause of adult-onset obesity. We found that functional inactivation of a single allele of the homeobox gene Prox1 led to adult-onset obesity due to abnormal lymph leakage from mispatterned and ruptured lymphatic vessels. Prox1 heterozygous mice are a new model for adult-onset obesity and lymphatic vascular disease.