Proteolytic enzymes in green wheat leaves II. Purification by affinity chromatography, and some properties of proteinases with acid pH optima

A comparison of haemoglobin, 2,4-dinitrophenyl and N,O-dibenzyloxycarbonyltyrosineas ligands for the affinity chromatography of wheat-leaf proteinasesdelete widi acid pH optima, established that haemoglobin wasthe most satisfactory. Using haemoglo-bin-Sepharose 4B affinitychromatography it was possible to purify wheat-leaf acid proteinases,previously isolated on DEAE-cellulose, to homogeneity as judgedby polyacrylamide gel electrophoresis. Some properties of threepurified proteinases are presented and discussed. (Received January 17, 1978; )     

Motor practice and neurophysiological adaptation in the cerebellum: a positron tomography study.

We have used positron tomography (PET) to demonstrate that some parts of the motor system exhibit physiological adaptation during the repeated performance of a simple motor task, but others do not. In contrast to the primary sensori-motor cortex, the cerebellum exhibits a decrease in physiological activation (increases in regional blood flow during performance) with practice. A new application of factorial experimental design to PET activation studies was used to make these measurements in four normal males. This design allowed adaptation to be examined by testing for an interaction between regional cerebral blood flow (rCBF) increases brought about by a motor task and the number of trials (time). These findings are interpreted as the neurophysiological correlates of synaptic changes in the cerebellum associated with motor learning in man.     

A morphologic classification and incidence of alveolar-bronchiolar neoplasms in BALB/c female mice

Lungs from 505 (21.1%) of 2,397 untreated control female BALB/c mice examined at various age intervals up to 1,001 days contained alveolar-bronchiolar neoplasms. Tumors were evaluated for histomorphological type, degree of differentiation, and size. Most of the tumors (286 of 505 or 56% of those examined) were of the papillary type and 450 of 505 (89.1%) were well differentiated. The incidence of the solid type and the well differentiated tumors was highest in the smallest size group (less than 0.5 mm) while that of the papillary and mixed types and the moderately and poorly differentiated tumors was highest in the larger size groupings. One hundred twenty-seven of 131 (97%) of all solid tumors were well differentiated while a lower percentage of papillary and mixed types (86.7% and 85.2%, respectively) were well differentiated. The mean age of mice with tumors from each histomorphological type, degree of differentiation, and size grouping also was determined.     

Oxytocin Influences Male Sexual Activity via Non-synaptic Axonal Release in the Spinal Cord

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frizzled 9 is expressed in neural precursor cells in the developing neural tube

The wnt signaling pathway has important functions in nervous system development. To better understand this process we have cloned and analyzed the expression of the wnt receptor, frizzled 9, in the developing nervous system in mouse, chick and zebrafish. The earliest expression of mouse frizzled 9 mRNA expression begins at E8.5 with expression throughout the entire rostral-caudal neuraxis. This early expression pattern within the neural tube appears to be conserved between chick and zebrafish. Expression becomes restricted to a ventral domain in the mouse ventricular zone at E11.5, a region specified to give rise to neurons and glia. Using a polyclonal antibody to MFZ9 further shows expression limited to neural restricted precursors cells.