Mutations in genes in the renin-angiotensin system are associated with autosomal recessive renal tubular dysgenesis

Autosomal recessive renal tubular dysgenesis is a severe disorder of renal tubular development characterized by persistent fetal anuria and perinatal death, probably due to pulmonary hypoplasia from early-onset oligohydramnios (Potter phenotype). Absence or paucity of differentiated proximal tubules is the histopathological hallmark of the disease and may be associated with skull ossification defects. We studied 11 individuals with renal tubular dysgenesis, belonging to nine families, and found that they had homozygous or compound heterozygous mutations in the genes encoding renin, angiotensinogen, angiotensin converting enzyme or angiotensin II receptor type 1. We propose that renal lesions and early anuria result from chronic low perfusion pressure of the fetal kidney, a consequence of renin-angiotensin system inactivity. This is the first identification to our knowledge of a renal mendelian disorder linked to genetic defects in the renin-angiotensin system, highlighting the crucial role of the renin-angiotensin system in human kidney development.     

Nuclear morphology in the nutritive cells ofDrosophila testes

Resumen Se describe en microscopía óptica una serie de estructuras características dentro del núcleo de celulas nutricias viventes en testículos de varias especies deDrosophila. Estas estructuras consisten en corpúsculos densos, homogeneos o vaculados, y en masas de material difuso o granular.

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Supported by The Population Council, Inc., New York.     

Halbe haploide Chromosomenzahl im Hoden vonMyrmica sulcinodis Nyl. (Formicidae)

Summary In the testes ofMyrmica sulcinodis there are not only haploid and some diploid cells to be found, as in the testes ofM. ruginodis, M. sabulsti andM. rubida, but a large mass of cells that have only half the haploid chromosome number. The diploid chromosome number ofM. sulcinodis is 56, those of six otherMyrmica species are between 42 and 48.     

Serendipitous precise and unique staining of cell nuclei

Zusammenfassung Frischgefrorene Gewebesektionen verschiedener Gewebe wurden in Kalium-Eisen-Cyanid bei pH 5,2 inkubiert; dabei wurde eine präzise und einzigartige Färbung nur der Zellnuklei beobachtet. Die Ursache dieser selektiven Kernfärbung ist nicht verständlich, doch stellt sie höchstwahrscheinlich eine Färbung von Ferro-Verbindungen in den Nuklei dar.

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This investigation was supported in part by Public Health Service Research Grants Nos. CA 02624 and CA 02903 from the National Cancer Institute and in part by an institutional grant to the Detroit Institute of Cancer Research Division of the Michigan Cancer Foundation from the United Foundation of Greater Detroit, and Detroit General Hospital Research Corporation. Newaygo County Cancer Association. We wish to express our gratitude for stenographic assistance to Mrs.Georgette M. Bellmay.     

Feulgen positive nucleoli in Epon semithin sections: fact or artifact?

Epon semithin sections from glutaraldehyde fixed tissues show stained nucleoli after treatment with the Schiff's reagent. The possibility that aldehyde groups already present could account for this positive staining reaction is briefly discussed.     

The indigogenic reaction for histochemical demonstration of alkaline and acid phosphatase

Résumé Le principe indigogénique à la détection histochimique des phosphates alcalins et acides a été appliqué. Ces substrates ont l'avantage de permettre une localisation précise de l'enzyme, sans ou avec minime diffusion. C'est aussi une méthode simple et directe pour la mise en évidence de ces enzymes sans passer par une réaction couplée. Un bisindigo très insoluble a lieu apparaît aux points d'activité enzymatique. Le 5-bromo-4-chlorocomposé donne un indigo bleu-vert tandis que le 5-bromo-6-chloro-composé donne un indigo magenta.     

Sound-stimulated14C-glutamate release from the nucleus cochlearis

Summary The exogenous release of glutamate has been successfully studied in the cochlear nucleus of guinea-pigs after physiological sound stimulation of the ear (frequency 2000–20,000 Hz at 100 dBA).Acknowledgments. This study was supported by grants from the Swedish Medical Research Council (B80-12X-05666-01) and Torsten Söderbergs och Ragnar Söderbergs stiftelser.     

Prenucleolar bodies in the cytoplasm of meristematic cells after thermal shock

Resumen Uno de los efectos producidos por el choque térmico, a temperaturas supraóptimas y subletales, sobre células meristemáticas deA. cepa es la aparición de cuerpos argentófilos en el citoplasma de las células telofásicas. Las características citoquímicas y ultraestructurales de estos cuerpos permiten identificarlos con los cuerpos prenucleolares.

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The work reported in this paper was undertaken during the tenure of a Research Training Fellowship awarded by the International Agency for Research on Cancer.