Prospects for NMR imaging in the study of biological morphogenesis

Small objects can be visualised with a spatial resolution that approaches microscopic dimensions using the technique of high resolution nuclear magnetic resonance (NMR) imaging. Some important features of the method are described and the prospects for using the technique to study morphogenesis are discussed. It is concluded that NMR imaging, in conjunction with the related method of localised spectroscopy, is capable of producing novel structural information.     

Prospects for NMR imaging in the study of biological morphogenesis

Summary Small objects can be visualised with a spatial resolution that approaches microscopic dimensions using the technique of high resolution nuclear magnetic resonance (NMR) imaging. Some important features of the method are described and the prospects for using the technique to study morphogenesis are discussed. It is concluded that NMR imaging, in conjunction with the related method of localised spectroscopy, is capable of producing novel structural information.     

Partial migration in birds: experimental proof of polymorphism as a controlling system

Summary When, from a partially migratory population of blackcaps, migratory-active (a) and-inactive (i) individuals were bred, the a×a pairs produced more birds of the type a than the original population and the i×i pairs, and the latter also more birds of the type i than the original population. Thus the characters migratory and resident in the blackcap are inherited and polymorphism is now demonstrated as a controlling system for partial migration in birds.With support by the Deutsche Forschungsgemeinschaft.We thank the French embassy for arranging permission to collect experimental birds.     

Orientation in birds: a foreword

The Editors wish to thank Professor P. Berthold for coordinating this multi-author review.     

Gastrulation in the housefly,Musca vicina,macquart

Résumé L'«innere blastemma» de l'uf de la mouche domestique est riche en acide ribonucléique et en glycogène. Ce stratum s'incorpore dans le blastoderme et le mouvement gastrulaire commence peu après, avant même que la délimitation des cellules soit complète. La signification de ce caractère est soulignée.     

Evaluation of oral vaccination against mouse-typhoid in a new animal model

Summary In a simple, new animal model the spread of mouse-typhoid within a mouse-colony was studied and oral vaccination against this disease was evaluated. Live vaccine was superior to inactivated vaccine.     

Measuring migratory restlessness in captive birds by an ultrasonic system

Summary A new simple ultrasonic system is described with which whirring and hopping, expressions of noctural migratory activity in captive birds, can be measured. Pronounced differences are found if the results are compared with those from the most often used perch-microswitch system, which responds only to hopping.     

A study of the mode of action of chloramphenicol on the chick morphogenesis

Zusammenfassung Hühnerembryonen, die in vitro mit Chloramphenicol behandelt wurden, zeigten verschiedene Missbildungen, wie Mikrocephalie, offene Neuralrinne, gerade bleibenden Herzschlauch, verkürzte Körperachse. Nachbehandlung solcher Chloramphenicol-Keime mit äquimolaren Lösungen von Phenylalanin, Tyrosin oderOrtho-Aminobenzoesäure ergibt weitgehend oder völlig normale Entwicklung. Durch Behandlung mit Alanin, Phenylmilchsäure oderPara-Aminobenzoesäure wird dagegen die Chloramphenicolwirkung nicht aufgehoben. Auf Grund dieser Ergebnisse wird der mögliche Mechanismus der Chloramphenicolwirkung diskutiert.

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One of us (L.M.) wishes to thank the Atomic Energy Commission for financial assistance.     

Renal ammonia production as a model for the study of enzyme adaptation in mammals

Zusammenfassung Chronische Verabreichung von Säure führt zu einer erhöhten Glutaminase-I-Konzentration in der Niere und zu einer gesteigerten Ammoniakausscheidung im Urin. Das ammoniakproduzierende biokatalytische System (Glutaminase I) ist besonders gut zum Studium der Enzymadaptation (Induktion) bei Säugetieren geeignet. Der Stand der Adaptation kann nicht nur durch die Bestimmung der Enzymveränderungen in der Niere, sondern auch durch den Nachweis des Reaktionsproduktes (Ammoniak) im Urin am lebenden Tier beurteilt werden.

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This investigation was supported by a research grant, RG-3795, from the National Institutes of Health, United States Public Health Service.     

Re-examination of Rattus norvegicus as an animal model for Aeromonas-associated enteritis in man

We have developed an oral feeding model for Aeromonas hydrophila enteritis using Rattus norvegicus with clindamycin pretreatment. All animals in the clindamycin group developed a self-limited, loose stool by day four of feeding. Intestinal examination revealed evidence of enteritis. Moreover, antibiotic usage may be a predisposing risk factor to infection.     

Heavy and light roles: myosin in the morphogenesis of the heart

Myosin is an essential component of cardiac muscle, from the onset of cardiogenesis through to the adult heart. Although traditionally known for its role in energy transduction and force development, recent studies suggest that both myosin heavy-chain and myosin light-chain proteins are required for a correctly formed heart. Myosins are structural proteins that are not only expressed from early stages of heart development, but when mutated in humans they may give rise to congenital heart defects. This review will discuss the roles of myosin, specifically with regards to the developing heart. The expression of each myosin protein will be described, and the effects that altering expression has on the heart in embryogenesis in different animal models will be discussed. The human molecular genetics of the myosins will also be reviewed.