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Notes: It has been an earnest desire of protein crystallographers to collect fast, accurate, high resolution diffraction data from protein crystals, preferably with exposure time as short as possible. In order to meet this challenge, a new type of Weissenberg camera has been developed for the recording of diffraction intensity from protein crystals using synchrotron radiation. The BL6A2 line has a plane-bending mirror designed by Y. Sato. The optical bench with triangular tilt-cut Si crystal monochromator was designed by N. Kamiya and was installed in the BL6A2 hutch. The Weissenberg camera was set on the 2θ arm of the optical bench. This camera can be used with Fuji Imaging Plate (IP) as an x-ray detector, and the reading out of the image from the IP is carried out by using BA100. The characterization of this system was carried out using the native crystal of chicken gizzard G-actin DNase I complex and its Yb3+, PCMB, indium, and FMA derivatives. Since these crystals are very sensitive for x rays, the resolution limit of the diffraction was 5 A(ring) with a 4-circle diffractometer on a rotating anode x-ray generator (N. Sakabe et al., J. Biochem. 95, 887. This complex was crystallized in space group P2,2,2, with a=42.0, b=225.3, and c=77.4 A(ring). The data were collected with this system with the 430-mm radius cassette when Photon Factory was operated at 2.5 GeV and 270 mA and the wavelength λ=1.004 A(ring) was chosen. In order to avoid overlapping of diffraction spots, oscillation angle range and coupling constant (degree/mm) were settled on the basis of simulation patterns of diffraction spots up to the maximum resolution to be measured considering the direction of the crystal axes, wavelength, radius of the camera, and mosaicness of the crystal. When the oscillation axis was a axis, the oscillation angle range was selected at either 10° (1°/mm) or 5° (0.5°/mm) depending on the density of reciprocal lattice points along the incident beam, and typical exposure time in each IP was 50 and 25 s, respectively. The exposure was stopped after 10 times oscillation. The total range of 117.5° was recorded on 16 sheets of IP with an overlapping range 0.5°.The data processing was carried out using program weis coded by T. Higashi. Two complete data sets along the a and c axes were collected using two crystals, independently, and the merge R(F2) for native crystal was 0.068. In order to know the feasibility of the data (F+−F−), Patterson maps were calculated with data of each derivative, and heavy atom vectors clearly appeared as prominent peaks in the Harker sections of the Patterson maps of both Yb3+ and PCMB derivatives. The heavy atom positions were obtained from the combinations of different Patterson and different Fourier maps, and were refined by using least-squares techniques. The final figure of merit up to 2.5 A(ring) resolution was 0.61 with 22 700 reflections. The assignment of DNase I part on the electron density maps is progressing using the Nicholson molecular model referring to its structure reported by C. Oefner and D. Suck [J. Mol. Biol. 192, 605 (1986)]. In addition to promising results of ω-aminoacid pyruvate aminotransferase [N. Watanabe et al., Book of abstracts of second Japan-China Bilateral Symposium on Biophysics, p. 83 (1988)], these results support that this data collection system consisting of a new type of Weissenberg camera using SR, Fuji Imaging Plate, BA100, and program weis is one of the fastest and most accurate systems for protein crystallography in use today. We thank the Education Ministry and the Foundations of Yamada, Naito and Toray for the financial support of this project. We are grateful to Dr. K. Namba of ERATO for our use of BA100.

Notes: The spatial and temporal organization of climbing fibre activation of Purkinje cells, the so-called complex spikes, were studied in the rat cerebellar Crus II folium utilizing a multiple microeletrode recording technique. As many as 32 Purkinje cells could be simultaneously recorded by using a custom-built electronic amplifier system and a special data storage device. Analysis of the auto-correlation activity of complex spikes in any given group of Purkinje cells indicated that activation occurs with a particular rhythmicity having a base firing of 10 Hz. Cross-correlation of spontaneous complex spikes demonstrated, in addition to a particular rhythmicity, an extraordinarily high degree of synchronicity within a particular spatial distribution of Purkinje cells. Thus, Purkinje cells organized in rostra-caudal rows tend to fire within 1 ms of each other for distances as far as 800 μm (the width of a folium) from the ‘master’ neuron. By contrast, Purkinje cells located medial or lateral to the master neuron showed almost no cross-correlation. Administration of harmaline to the animal increased the degree of auto- and cross-correlation but did not change the spatial order of the distribution of the cross-correlation. The results indicate that the olivo-cerebellar system is organized in such a way that climbing fibre afferents may be activated in a close-to-synchronous and rhythmic fashion. The spatial distribution of these afferents over the cortex is such as to activate rostro-caudal bands of Purkinje cells which tend to fire in a close-to-synchronous manner.

Notes: Multiple recordings from Purkinje cells in the rat cerebellum allowed the mechanism responsible for the activation of rows of synchronous complex spikes to be investigated. By determining the spatial distribution of the climbing fibre reflex that follows electrical microstimulation of the cerebellar cortex, it was shown that the mechanism for the simultaneity of firing was the electrotonic interactions between neurons in the inferior olive (IO). The spatial organization of the complex spike activity was shown to be regulated by GABAergic inhibitory input into the IO, probably arising from the cerebellar nuclear neurons. The rostro-caudal organizion of the complex spike activity following physiological stimulation (tactile stimulation of the upper and lower lip) demonstrated the same spatial distribution of synchronous activity in the cerebellar cortex as did the spontaneous activity and this was also disrupted by GABA blockers. Finally, complex spike responses to physiological stimulation indicate that the IO is capable of gating sensory inputs in accordance with its intrinsic autorhythmicity and that strong peripheral stimuli reset the oscillatory properties of the IO. The functional implications of the synchronicity and of the temporo-spatial organizion of complex spikes in the cerebellar cortex are discussed in the context of motor coordination and timing.

Notes: Summary Voluntary dislocation of the hip is very uncommon. Only twelve cases have been reported and most affected one hip. We report voluntary dislocation of both hips in a three year old girl which gradually resolved without treatment.

Notes: Summary A 46-year-old woman presented acute sensori-motor neuropathy of the Guillain-Barré type, followed by a protracted course of profound autonomic and sensory dysfunction. Tests of autonomic functions showed denervation hypersensitivity. Neuropathologically, the trigeminal sensory nuclei, solitary nucleus, the dorsal columns of the spinal cord and dorsal spinal roots showed severe degeneration. Degeneration was found both in the preganglionic (intermediolateral cell columns of the spinal cord) and postganglionic (sympathetic ganglion and celiac ganglion) neurons of the sympathetic nervous system, and the preganglionic (dorsal motor nucleus of the vagus) and postganglionic (Auerbach's plexus) neurons of the parasympathetic nervous system.

Notes: Summary This is the first autopsy case report of a syndrome with autosomal recessive inheritance, muscular atrophy, contracture, skin eruption, hyper γ-globulinemia, decreased subcutaneous fat, mental retardation and abnormal ECG findings. Skeletal muscles showed severe, discrete, multifocal muscular fibrosis which replaced several primary fasciculi. The tongue, heart and extraocular muscles showed identical but less severe findings. In the involved muscle fasciculi, veins and venules as well as arteries and arterioles showed medial hyperplasia and luminal constriction. Degeneration of endothelial cells of arterioles and narrowing of the lumen of terminal arterioles by the debris were observed. The peripheral nerves in the muscles were relatively well preserved. The correlation and pathogenesis of these findings are discussed.

Notes: Summary A component-spectroanalysis technique was used to study the multicolor properties of histochemically stained tissue sections. We developed a method that makes it possible to obtain separately both the spectral patterns and spatial distributions of different color components in tissue sections. To illustrate the application of this technique, we examined the extinction spectrum of reduced nitroblue tetrazolium (NBT), which is used for the detection of dehydrogenase activity. Upon the reduction of NBT, mono-and diformazans are formed, and these exhibit overlapping extinction spectra. When succinate dehydrogenase (SDH) activity in rat liver lobules was examined using NBT, monoformazan was found to be present at higher concentrations than diformazan and to have a uniform distribution, whereas the concentration of diformazan increased with a steep gradient between the center and periphery of lobules. In rat skeletal muscle fibers, diformazan was present at higher concentrations than monoformazan. The level of SDH activity was topographically represented by the hydrogen concentration calculated from the concentrations of the two formazans. This method is effective for separating multiple components such as mono-and diformazans in histochemical reactions.

Notes: Summary Monkeys were trained to perform hand movements in a reaction time task with discrimination between positive (go) and negative (no-go) light signals, and field potentials in various cortical areas were recorded and analysed with chronically implanted cortical electrodes. As previously reported, areas such as the prefrontal, premotor and motor cortices were active in association with simple visually-initiated, reaction-time hand movements. The caudal part of the dorsal bank of the principal sulcus was found to be activated specifically on no-go trials during discrimination, and revealed a relatively sharp surface-negative, depth-positive potential. The potential appeared at a latency of 110–150 ms, which was 150–210 ms earlier than the movement onset on go trials. With reversal of the go and no-go signals, this potential was found to be recorded only on no-go trials, irrespective of the colour used for the stimulus. It is suggested that the activity in the dorsal bank of the principal sulcus is related to the judgement not to execute the movement and/or the suppression of motor execution.