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Study design:Experimental training model of rats with spinal cord injury (SCI).Setting:Osaka, JapanObjective:To investigate the effect of forced treadmill training by plantar placement (PP), as compared with dorsal placement (DP), of the dorsal paws on the locomotor behaviors of spinal cord-injured rats.Methods:The spinal cord was contusion-injured at the thoracic level. Rats were divided into three groups: forced training involving stepping by PP and DP and non-forced training/assistance (nT). Training began 1 week after injury and was conducted for 4 weeks. Locomotor behaviors were estimated using Basso–Beattie–Bresnahan (BBB) scores, dorsiflexion of the hind paws and footprints of the hind paws. Histological and immunohistochemical examinations of the spinal cord lesions were conducted after 4 weeks of training.Results:The values, respectively, of PP, DP and nT groups at 4 weeks of training were as follows: BBB scores were 15.6±0.8, 7.7±1.3 and 10.3±0.4. The paw dorsiflexion angles were 34.1±5.2, 16.4±2.4 and 23.6±3.0 degrees, respectively. The stride angles were 5.1±0.9, 13.7±4.9 and 17.8±4.0 degrees for the left paws. Cavity volumes were 10.3±2.1, 31.0±2.0 and 28.2±4.9%. In addition to cavities, there were astrocyte-devoid areas containing some loose tissues, through which many axons extended longitudinally.Conclusions:The BBB score, dorsiflexion angle and stride angle were consistently improved in the PP group. Cavity formation was more reduced, and many axons extended through coarse tissues formed in astrocyte-devoid areas at the lesion in the PP group. Forced training by PP of the hind paws promoted the behavioral and histological improvement of rats with SCI.

A micro-tomographic System developed at BL47XU in SPring-8 (SP-μCT 47XU) was used to obtain three-dimensional structures of synthetic and natural substances for a test study. Al2O3-YAG cutectic composites, synthetic quartzites (SiO2) and Antarctic micro-meteorites (AMMs) were successfully imaged with the spatial resolution of 1 μm three-dimensionally. Three-dimensional elemental distribution was also obtained using X-ray adsorption edge of Fe in the measurement of an AMM.

A white rot basidiomycete, Ceriporiopsis subvermispora, degraded vulcanized natural rubber (NR) sheets on a wood medium. The fungus decreased the total sulfur content of the rubber by 29% in 200 days, accompanied by the cleavage of sulfide bonds between polyisoprene chains. X-ray photoelectron spectroscopy (XPS) demonstrated that C. subvermispora reduced the frequency of S−C bonds by 69% with a concomitant formation of S−O bonds during the culture period. Dipolar decoupling/magic angle spinning (DD/MAS) solid state ¹³C NMR revealed that the fungus preferentially decomposed monosulfide bonds linked to a cis- and trans-1,4-isoprene backbone but the cleavage of polysulfide bonds was also observed. In contrast, no decrease in weight or devulcanization of rubber was observed in cultures of a white rot fungus, Dichomitus squalens. The oxidative cleavage of sulfide bonds by C. subvermispora demonstrates that ligninolytic basidiomycetes are potential microbes for the biological devulcanization of rubber products.

A mechanical study on skinned rat psoas muscle fibers was performed at about 16°C with X-ray diffraction and caged-ATP photolysis. The amount of photoreleased ATP was set <0.2 mM for analysis of a `single turnover' of the cross-bridge ATPase. With regard to the phase of activation, the results under the single turn-over condition were generally consistent with previous results obtained with larger amount of photoreleased ATP. Formation of the ADP-rigor state was mechanically monitored by the 90° out-of-phase component of stiffness at 500 Hz, which was elevated on activation and then decreased to zero with a half-time of 0.2–0.3 s. Intensity changes of the X-ray reflections (e.g. equatorial reflections, actin layer lines and a myosin meridional reflection) indicated that a large number of cross-bridges returned to the rigor structure with a half-time of 0.5–0.7 s. During this phase, tension did not increase but slowly decreased with a half-time of about 1.0 s. The in-phase stiffness increased only 20–30% at the most. These results indicate that, even if the number of cross-bridges formed at any moment during full contraction is small, they can interact with actin and form rigor bonds with a rate of 1 s−1. The force developed in the rigor formation is probably lost due to the presence of rigor bridges and compliance in the preparation.

An energy spectrum of electrons from 180 to 550 keV precipitating into the dayside polar ionosphere was observed under a geomagnetically quiet condition (AE ≤ 100 nT, Kp = 1‐). The observation was carried out at 73–184 km altitudes by the HEP instrument onboard the RockSat‐XN sounding rocket that has been launched from Andøya, Norway. The observed energy spectrum of precipitating electrons follows a power law of −4.9 ± 0.4 and the electron flux does not vary much over the observation period (∼274.4 s). A nearby ground‐based VLF receiver observation at Lovozero, Russia shows the presence of whistler‐mode wave activities during the rocket observation. A few minutes before the RockSat‐XN observation, POES18/MEPED observed precipitating electrons, which also suggest whistler‐mode chorus wave activities at the location close to the rocket trajectory. A test‐particle simulation for wave‐particle interactions was carried out using the data of the Arase satellite as the initial condition which was located on the duskside. The result of the simulation shows that whistler‐mode waves can resonate with sub‐relativistic electrons at high latitudes. These results suggest that the precipitation observed by RockSat‐XN is likely to be caused by the wave‐particle interactions between whistler‐mode waves and sub‐relativistic electrons. Sub‐relativistic electrons precipitating into the Earth's dayside polar ionosphere are observed by a sounding rocket under geomagnetically quiet conditions. An energy spectrum of these electrons in an energy range from 180 to 550 keV is reported at the rocket altitude. A possible mechanism for generating this precipitation is the resonance scattering of electrons by whistler‐mode waves, which we conducted a test‐particle simulation based on the ground and satellite observations. A sounding rocket observed an energy spectrum of sub‐relativistic electron precipitation in the dayside polar ionosphere during quiet timeGround and satellite observations suggest that the precipitation observed by RockSat‐XN was caused by the whistler‐mode wavesA test‐particle simulation for wave‐particle interactions based on the data of the Arase satellite supports the RockSat‐XN observation A sounding rocket observed an energy spectrum of sub‐relativistic electron precipitation in the dayside polar ionosphere during quiet time Ground and satellite observations suggest that the precipitation observed by RockSat‐XN was caused by the whistler‐mode waves A test‐particle simulation for wave‐particle interactions based on the data of the Arase satellite supports the RockSat‐XN observation

Objective: The aim of this study is to compare the pulmonary function after a segmentectomy with that after a lobectomy for small peripheral carcinoma of the lung. Patients And Methods: Between 1993 and 1996, segmentectomy and lobectomy were performed on 48 and 133 good-risk patients, respectively. Lymph node metastases were detected after the operation in 6 and 24 patients of the segmentectomy and lobectomy groups, respectively. For bias reduction in comparison with a nonrandomized control group, we paired 40 segmentectomy patients with 40 lobectomy patients using nearest available matching method on the estimated propensity score. Results: Twelve months after the operation, the segmentectomy and lobectomy groups had forced vital capacities of 2.67 +/- 0.73 L (mean +/- standard deviation) and 2.57 +/- 0.59 L, which were calculated to be 94.9% +/- 10.6% and 91.0% +/- 13.2% of the preoperative values (P = .14), respectively. The segmentectomy and lobectomy groups had postoperative 1-second forced expiratory volumes of 1.99 +/- 0.63 L and 1.95 +/- 0.49 L, which were calculated to be 93.3% +/- 10.3% and 87.3% +/- 14.0% of the preoperative values, respectively (P = .03). The multiple linear regression analysis showed that the alternative of segmentectomy or lobectomy was not a determinant for postoperative forced vital capacity but did affect postoperative 1-second forced expiratory volume. Conclusion: Pulmonary function after a segmentectomy for a good-risk patient is slightly better than that after a lobectomy. However, segmentectomy should be still the surgical procedure for only poor-risk patients because of the difficulty in excluding patients with metastatic lymph nodes from the candidates for the procedure. (J Thorac Cardiovasc Surg 1999;118:536-41)

Hypothermia is reported to increase intensive care unit (ICU) mortality. The heat loss that occurs during continuous renal replacement therapy (CRRT) favors the development of hypothermia. In an effort to assess the influence of CRRT on body temperature, we reviewed the records of 72 consecutive ICU patients treated with CRRT and further prospectively studied the temperature in the inlet and outlet lines for blood and dialysate of 27 other patients at various flow settings during continuous venovenous hemodialysis (CVVHD). Among the 72 retrospective cases, 36 episodes of hypothermia (core body temperature <35.5 degrees C) occurred and persisted for a mean of 2.6+/- 1.8 days. It was more frequent during venovenous than arteriovenous modalities (31 of 67 v5 of 20, respectively); no patients developed hypothermia during arteriovenous slow continuous ultrafiltration (AVSCUS), whereas 48% of the patients undergoing CVVHD became hypothermic, occurring earlier in the therapy course (days 2 to 4). Mean arterial pressure (MAP) tended to increase after CRRT initiation, but absolute changes were not statistically significant. In the prospective arm, the CVVHD circuit temperatures were directly measured. Whereas no attempt was made to change body temperature, stepwise changes in blood (Qb) and dialysate flow rate (Qd) produced venous circuit temperature changes: the higher the Qb, the smaller the arteriovenous temperature differences independent of changes in Qd (P < 0.001). Also, venous circuit temperature varied directly with Qd at fixed Qb (P < 0.001). This relationship also held for temperature conversion to lost energy units per minute. Using room temperature dialysate, CRRT may significantly lower patients' core temperatures. Although the clinical significance of this effect is not clear at this point, energy loss during CVVHD may be important in hemodynamic stability or patient prognosis. (Am J Kidney Dis 1998 Dec;32(6):1023-30)

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Using an imaging plate exchanger and a synchrotron X-ray source, X-ray diffraction patterns were recorded from frog skeletal muscles shortening near the maximum velocity from a sarcomere length of 2·6 to 2·1 µm. The major findings were as follows: (1) the intensity of the second-order myosin meridional reflection, which decreased to 18% of the resting value during isometric contraction, increased to 34% during shortening, showing that the perturbation in the axial arrangement of myosin heads recovered. (2) The intensity of the third-order myosin meridional reflection increased by 32% on isometric contraction and decreased to 51% of the resting intensity during rapid shortening, showing disorder in the axial arrangement of the myosin heads. (3) The axial Bragg spacing of the third-order meridional reflection, which increased by 1·22% during insometric contraction, was still 0·47% larger than the resting value during shortening, indicating that the increase is not entirely due to extension of the filament by tension. (4) The intensity ratio of the (1,0) and (1,1) equatorial reflections increased a small extent (from ·to 0·62) during shortening, while the 5·9 nm and 5·1 nm actin layer-lines showed large intensity decreases (126 to 101% and 190 to 124% of the resting intensity, respectively), suggesting that considerable numbers of myosin heads are in the vicinity of the thin filament but not tightly bound to actin molecules during rapid shortening. These results are consistent with a model of muscle contraction in which myosin heads attach to actin in two different manners with weak and strong affinities and show that, during shortening, the number of thightly attached heads decreases by half, while the total number of attached heads decreases only slightly. Copyright 1993, 1999 Academic Press

1. By applying the X‐ray diffraction method to chemically skinned papillary muscles of the rat, the transfer of myosin heads from the thick to the thin filaments was studied as a function of Ca2+ concentration. 2. No significant transfer of the heads occurred when the Ca2+ concentration was below the threshold of contraction (pCa 6.2). 3. During the maximum isometric contraction at pCa 4.4, 80% of the myosin heads were transferred to the thin filament. 4. When the muscle was activated isometrically at low Ca2+ concentrations (pCa 6.2‐5.8), where the average tension was less than 20% of the maximum, a disproportionately large number of myosin heads were transferred to the thin filament. 5. It was concluded that a significant fraction of the heads transferred at the low Ca2+ concentrations does not produce tension.

1. Fast (posterior latissimus dorsi, PLD) and slow (anterior latissimus dorsi, ALD) muscles of the chick were studied by time‐resolved X‐ray diffraction using a synchrotron radiation source. 2. In both muscles and at both 20 and 30 degrees C, intensities of the X‐ray equatorial reflections changed faster than tension at the beginning of tetanus. When the intensity change was converted into the mass transfer from the thick to the thin filament, the difference between the half‐rise times of the transfer and tension development at 20 degrees C was 140 ms in ALD and 37 ms in PLD. At 30 degrees C it was 110 ms and 10‐20 ms for ALD and PLD respectively. 3. These results indicate that in the early stage of contraction, some of the myosin heads in the vicinity of the thin filament are developing little or no tension, and suggest that the fast and slow muscles differ in the transition rate of myosin heads from the state of attachment with low tension to that with high tension.

1. A position sensitive X‐ray counter was connected to a data‐collection system which registered the outputs of the counter as a function of time. This enabled us to study time‐dependent changes in the intensities of the equatorial reflexions from frog sartorius muscle during an isometric twitch. 2. The intensity ratio of the 1.0 and 1.1 equatorial reflexions (I1,0/I1,1) decreased during a twitch. The time at which the intensity ratio started to decrease coinsided approximately with the onset of tension development. No detectable change in the intensity ratio occurred during the latency relaxation. 3. The intensity ratio reached a minimum level approximately 90 msec before the peak of tension, and stayed at that level until the peak tension. 4. The intensity ratio returned to the 'resting' value 0.7‐‐1.1 sec after the twitch tension had fallen to zero. 5. The observed decrease in the intensity ratio was interpreted as being caused by radial movements of the myosin projections from the vicinity of thick filaments to that of thin filaments. This leads us to conclude that, early in the rising phase of twitch tension, the number of myosin projections in the vicinity of thin filaments reaches the value obtained during a maximum isometric tetanus.

A mouse toe muscle was chemically skinned with saponin and the 1,0 spacing of the hexagonal myofilament lattice at a sarcomere length of 2.5 micron was measured with the X‐ray‐diffraction method. In the relaxed state, the 1,0 spacing was 40.8 nm. When the muscle was maximally activated at pCa 4.4, the spacing decreased to 38.4 nm. During contractions at lower calcium concentrations, the spacing decreased less. In rigor, the spacing decreased to almost the same extent as during maximum contraction, although the rigor tension was only 8% of the maximum tension. When the spacing in relaxed muscle had been adjusted osmotically to about 38 nm, activation caused no further decrease in the spacing. The results support the view that the force responsible for the lattice shrinkage during contraction is produced by cross‐bridges displaced from their optimum lateral positions.

The cross‐bridge movements underlying the tension responses of active muscle to slow length changes were studied by a time‐resolved X‐ray diffraction method. During an isometric tetanus at 2 degrees C, the meridional reflexion at 1/14.3 nm‐1 was 55% more intense than in the resting state, suggesting that the myosin heads maintain the 14.3 nm periodicity of the thick filament. When active muscle was stretched by 7% at a constant speed of 0.03‐0.70 muscle lengths s‐1, the intensity of the meridional reflexion decreased progressively as the tension increased continuously during the stretch. This suggests that the myosin heads spread out along the thick filament. During stress relaxation after a stretch, the intensity returned gradually toward the active isometric level, suggesting a rearrangement of the myosin heads. The meridional intensity changed in a similar manner when active muscle was released by 7% at the same speeds; it decreased progressively during the release and returned gradually to the isometric level after completion of the release. The intensity decrease during a release was smaller than that during a stretch, provided the speed was low (0.03‐0.09 muscle lengths s‐1). It was concluded that the tension responses to slow length changes are due to shifts of the myosin heads along the thick filament, and that the elastic element responsible for tension production is located in the myosin molecules.

1. The equatorial X‐ray diffraction pattern was recorded from a papillary muscle of a cross‐circulated canine heart at different phases of the cardiac cycle. The intensity ratio of the 1, 0 and the 1, 1 reflexions (I1, o/I1,1) was 0‐79 in the systolic phase and 1‐19 in the diastolic phase. 2. Using the intensity ratio obtained, the approximate proportion of the myosin projections present in the vicinity of the thin filaments was calculated. This was 70‐71% in the systolic phase and 51‐52% in the diastolic phase of the total myosin projections. 3. The peak systolic tension was roughly proportional to the proportion of the projections present in the vicinity of the thin filaments during systole. 4. The projections which stayed in the vicinity of the thin filaments during diastole did not produce significant contractile force.

X-ray diffraction patterns from frog sartorius muscle were recorded during steady shortening with various loads. The intensity of the third meridional reflection from the thick filament decreased on shortening to an extent proportional to the drop in tension. The intensity correlated more closely with the tension than with the shortening velocity. The Bragg spacing of the third meridional reflection decreased in proportion to the decrease in tension. The intensity decrease of the actin layer lines at 1/5.1 and 1/5.9 nm-1 was roughly proportional to the decrease in the load, indicating that the number of cross-bridges decreases similarly. The intensity of the (1,1) equatorial reflection showed a significant decrease only with low loads. Assuming that a steady structural state is attained during steady shortening, the results are consistent with the cross-bridge model in which the number of myosin cross-bridges decreases during shortening.

Summary The effects of N-ethylmaleimide (NEM) and other sulfhydryl modifiers on the structure of skinned frog skeletal muscles were studied using the X-ray diffraction technique. In sartorius muscle with full overlap between the thick and thin filaments, 0.1-1.0 mM NEM changed the intensity ratio of the (1,0) and (1,1) equatorial reflections from 4.35 to 0.72, and the (1,0) spacing of the hexagonal filament lattice from 40.4 to 41.4 nm. The axial X-ray diffraction pattern showed weak myosin layer-lines after the NEM treatment but enhancement of the actin layer-lines was not observed. In overstretched semitendinosus muscle, NEM did not affect the equatorial spacing but the myosin layer-lines were weakened. These results indicate that modification of myosin by NEM destroys the helical arrangement of myosin heads around the shaft of the thick filament and that when thin filaments are available, myosin heads move towards, and possibly bind to them. This binding is different from that in rigor since the ‘ladder-like’ appearance of the higher actin layer-lines, which is typical of patterns from rigor muscles, was not observed. On removal of ATP after the NEM treatment, the diffraction pattern showed features characteristic of that from normal rigor muscles but no tension was produced. The pattern showed well-defined samplings on layer-lines in the small-angle region, indicating the presence of an extensive lattice order and exact axial alignment of the filaments. The first actin layer-line did not show samplings from the superlattice of the thick filaments, which are observed on the myosin layer-lines in patterns from resting muscles. This indicates that in NEM-treated rigor muscles the pattern of binding of myosin heads to the thin filaments is not influenced by the azimuthal orientation of the thick filament.

Summary We studied the effects of BDM (2,3-butanedione monoxime) on the tetanic contraction of frog skeletal muscles using an X-ray diffraction technique. BDM significantly increased the resting equatorial intensity ratio (I1,0/I1,1). In sartorius muscle, 3mm BDM suppressed tetanic tension by 40–70% whereas the equatorial intensity ratio, which is 2.6 at rest, decreased to 0.75 during tetanus, close to the value in normal contraction (about 0.50). BDM (3mm) reduced the intensity increase of the 5.1-nm layer-line to 41%, that of the 5.9-nm layer-line to 24%, and the intensity decrease of the second myosin meridional reflection (at 1/21.5 nm-1) at 81%. In overstretched semitendinosus muscle, 3mm BDM did not significantly reduce the intensity increase of the second actin layer-line during activation, suggesting that enough calcium is released to activate the regulatory system and the regulatory proteins are intact. These results indicate that BDM suppresses tetanic tension by mainly inhibiting actin-myosin interaction. It has a smaller effect on the equatorial reflections and myosin layer-lines than on the actin layer-lines, suggesting that BDM-influenced myosin heads may bind to actin without following the symmetry of the actin helix.

A change in endocochlear potential (EP) following furosemide injection was observed in regard to prior glycerol administration in two groups of guinea pigs. In one group, various doses of furosemide (20, 30, 40, 50 mg/kg) were injected, while in the other, glycerol (50 v/v%, I ml/kg) was injected prior to the furosemide (20, 30, 40 mg/kg) injection. In the glycerol-furosemide group, the decrease in EP was 40% greater than in the furosemide group. Therefore, glycerol was thought to potentiate the EP lowering action of furosemide. Such an effect of glycerol was assumed to be resulted by facilitating the access of furosemide to the site of action in the stria vascularis.

Marked differences have been reported in the prevalence of glutamic acid decarboxylase (GAD) antibodies between Caucasian (63–84 %) and Japanese (30–50 %) or Asian (5–50 %) IDDM patients. Using a new immunoprecipitation assay based on 125l‐labelled recombinant human GAD65, we have reassessed prevalence of GAD65antibodies in Japanese patients. We also assessed prevalence of IA‐2 antibodies.

— The oxygenation of the perilymph in response to the intravenous injection of vasoactive drugs has been measured in 67 cats using the polarographic method. Of all drugs used, only angiotensin induced a significant raise of perilymphatic PO2. Histamine, 50% glycerol and 7% Na2CO3reduced the perilymphatic PO2. Papaverine, furosemid, pyridylcarbinol, naftidrofuryl and low molecular dextran have no significant effect upon the perilymphatic oxygen tension. Rapid changes of systemic blood pressure were found to correlate with subsequent modifications of the oxygen tension in the perilymphatic space.

1The cross‐bridges in slow‐ and fast‐twitch fibres (taken, respectively, from soleus and psoas muscles of rats) were examined in mechanical experiments using caged ATP and X‐ray diffraction, to compare their binding of ATP and ADP.2Caged ATP was photolysed in rigor fibres. When ADP was removed from pre‐photolysis fibres, the initial relaxation (±Ca2+) in soleus was as fast as that in psoas fibres, whereas the subsequent contraction (+Ca2+) was slower in soleus than in psoas. The ATPase rate during the steady‐state contraction was also slower in soleus fibres.3When ADP was added to pre‐photolysis fibres (±Ca2+), tension developed even in the initial phase, the overall tension development being biphasic. Both initial and late components of the Ca2+‐free contraction were enhanced when ADP was added before photolysis, although pre‐photolysis ADP was not a prerequisite for the late component. The effect of ADP was greater in soleus than in psoas fibres. Static experiments on rigor fibres revealed a higher ADP affinity in soleus fibres.4The intensity of the actin layer‐line from ADP rigor soleus fibres decreased rapidly on photorelease of ATP. We conclude that, despite the tight ADP binding of the soleus cross‐bridge, its isometric reaction is not rate limited by the ‘off’ rate of ADP.

The effect of a novel histamine H"2 receptor antagonist IT-066 (3-amino-4-[4-[4-(1-piperidinomethyl)-2-pyridyloxy]-cis-2-butenylamino]-3-cyclobutene-1,2-dione hydrochloride), on acute gastric mucosal injury induced by ischemia-reperfusion was investigated from the standpoint of oxygen radical-mediated lipid peroxidation in rats. Ischemia-reperfusion injury was produced in the rat stomach by applying a small vascular clamp to the celiac artery for 30 min and subsequent removal of the clamp for 60 min. The decrease in gastric mucosal blood flow was not influenced by treatment with IT-066. The antiulcer activity of IT-066 was demonstrated in this injury after intragastric ingestion as well as after intravenous injection. IT-066 significantly inhibited this injury in the presence of exogenous HCl. The mucosal protection by IT-066 was not reversed by pretreatment with indomethacin or nitric oxide synthase inhibitor. The increase in lipid peroxides in the gastric mucosa after ischemia-reperfusion was significantly inhibited by the intragastric treatment with IT-066 at doses of 1.0 and 3.0 mg/kg. The total area of erosions closely paralleled the accumulation of lipid peroxide with a significant correlation. A spin trapping method using 5,5-dimethyl-1-pyrroline-N-oxide showed that IT-066 scavenged superoxide radical and hydroxyl radical generated by the hypoxanthine-xanthine oxidase system and the hydrogen peroxide-ferrous iron system, respectively. IT-066 also significantly inhibited the in vitro increase of lipid peroxide in the gastric mucosal homogenates induced by a free radical initiator. These results suggest that the protective effect of IT-066 against ischemia/reperfusion-induced gastric mucosal injury may result in part from its antioxidative properties.

We have previously reported that in four transcription factor families the DNA-recognition rules can be described as (i) chemical rules, which list possible pairings between the 20 amino acid residues and the four DNA bases, and (ii) stereochemical rules, which describe the base and amino acid positions in contact. We have incorporated these rules into a computer program and examined the nature of the rules. Here we conclude that the DNA recognition rules are simple, logical, and consistent. The rules are specific enough to predict DNA-binding characteristics from a protein sequence.

Blutserum, Liquor cerebrospinalis und Perilymphe von Scala vestibuli und Scala tympani wurden von 85 normalen Meerschweinchen vor und nach i.v. Glycerolapplikation entnommen und die Na- und K-Konzentration bestimmt. Dabei wurde nach Glycerolgabe ein deutlicher Anstieg der Na-Konzentration in der Perilymphe der Scala tympani und im Liquor festgestellt, während die Perilymphe der Scala vestibuli keine Veränderungen zeigte. Die Zunahme der Na-Konzentration wird auf die Dehydration durch das Glycerol zurückgeführt, wobei die unterschiedliche Reaktion beider Perilymphen noch weiterer Untersuchungen bedarf. Die erhobenen Befunde könnten zur Aufklärung der Glycerolwirkung auf das Hören beim endolymphatischen Hydrops von Bedeutung sein.

The response of Purkinje neurons of the flocculus to caloric stimulation was investigated in the Urethane-chlorarose anesthetized rabbit. Twenty-five of 37 flocculus neurons which responded to ipsilateral caloric stimulation showed an increase in firing response, while 12 neurons showed a decrease. Fifteen of 28 flocculus neurons which responded to contralateral caloric stimulation showed an increase, while the firing of 13 neurons was decreased. Forty-one percent of flocculus neurons responded to ipsilateral caloric stimulation, and 41% responded to caloric stimulation of both sides. Eighteen percent of flocculus neurons responded only to contralateral stimulation. The ipsilateral flocculus may thus be responsible for the major control of the primary vestibular signal flow in the cerebellum.

The effect of the intravenous injection of cholinergic drugs on perilymphatic oxygen tension (Po2) was measured using the polarographic method in 20 cats. Acetylcholine, pilocarpine and neostigmine produced minimal but statistically significant changes in perilymphatic Po2. Atropine and scopolamine did not influence the Po2of the perilymphatic space. The reported results show that under normal conditions the cholinergic receptors of the vestibular vessels have little effect on the permeability of arterial Po2.

Summary The structure of the needle-shaped aggregate ofa-tropomyosin formed in the presence of Mg2+ ions (the Mg-tactoid) was studied by X-ray diffraction. Orientated specimens were prepared by magnetic orientation. The meridional reflections corresponding to a Bragg spacing of up to 2.6 nm were recorded and phased by the isomorphous replacement method usingp-chloromercuribenzoate bound to the unique cysteine residue of thea-chain of tropomyosin. The axial electron density profile thus obtained was compared with the model proposed from electron microscopic investigations. With an adequate phase combination for the observed intensities, the agreement was satisfactory. Comparison with electron micrographs of negatively stained Mg-tactoids suggests that the C-terminus of the molecule has an extended conformation and penetrates into the N-N overlap region. The principal repeat length along the tactoid was 39.0 nm, which was about 5% shorter than the expected periodicity of the tropomyosin molecules with an end-to-end overlap of eight residues, suggesting supercoiling. The equatorial reflections consisted of the diffuse peaks at 1/8 nm-1 and 1/2.3 nm-1. The former indicates, for the first time, the presence of a large structural unit with low crystallinity. The spacing of the latter probably corresponds to the average centre-to-centre distance between neighbouring tropomyosin molecules.

Structural changes of guinea pig taenia coli and rat anococcygeus muscle during contraction were studied by X-ray diffraction. The diffraction pattern of the taenia coli showed the 14.4-nm myosin reflection, the 5.9-nm actin layer-line and a diffuse equatorial peak at 1/11.4 nm-1. On application of carbachol, the muscle contracted and the intensity of the 14.4-nm reflection showed a concentration-dependent decrease: the maximum decrease was 24% at 2×10-5 M. Such an intensity decrease was not observed in K-contrature (154 mM). The intensity of the 5.9-nm actin layer-line did not change appreciably on activation. The equatorial peak became broader during contraction. The 14.4-nm myosin reflection of the anococcygeus muscle was weak. Its intensity increased by 106% during contraction induced by 2×10-5 M phenylephrine and by 75% during K-contracture. These results suggest that the number of myosin filaments may increase during contraction of rat anococcygeus muscle but not guinea pig taenia coli.

1. Local differences in the effects of stimulation of parts of the eye by light are expressed in Dixippus morosus by differential circus movements. 2. The angle of inclination of the body axis toward one source of light when the animal is on a vertical plane with light from one side is inversely proportional to the logarithm of the intensity of the light.

Whistler mode chorus waves scatter magnetospheric electrons and cause precipitation into the Earth's atmosphere. Previous measurements showed that nightside chorus waves are indeed responsible for diffuse/pulsating aurora. Although chorus waves and electron precipitation have also been detected on the dayside, their link has not been illustrated (or demonstrated) in detail compared to the nightside observations. Conventional low‐altitude satellite observations do not well resolve the energy range of 10–100 keV, hampering verification on resonance condition with chorus waves. In this paper we report observations of energetic electrons with energies of 30–100 keV that were made by the electron sensor installed on the NASA's sounding rocket RockSat‐XN. It was launched from the Andøya Space Center on the dayside (MLT ∼ 11 h) at the L‐value of ∼7 on January 13, 2019. Transient electron precipitation was observed at ∼50 keV with the duration of <100 s. The VLF receiver of a ground station at Kola peninsula in Russia near the rocket's footprint observed intermittent emissions of whistler‐mode waves at the VLF frequency range simultaneously with the rocket observations. The energy of precipitating electrons is consistent with those derived from the quasilinear theory of pitch angle scattering by chorus waves through cyclotron resonance, assuming a typical dayside magnetospheric electron density. Precise interaction region is discussed based on the obtained energy spectrum below 100 keV. The Earth's magnetosphere was filled with energetic electrons and various waves. Energetic electrons sometimes precipitate into the Earth's atmosphere and cause aurora. Whistler mode waves are believed to cause such precipitation and previous measurements showed that nightside chorus waves are responsible for aurora. Energetic electrons and chorus waves are also observed on the dayside magnetosphere. However, their link has not been illustrated in detail compared to the nightside observations. In this study, we verified the energy spectrum of precipitating electrons on the dayside by installing the sensor which can resolve the 30–100 keV energy range on a sounding rocket and observed transient electron precipitation. We conducted a sounding rocket experiment, which obtained detailed energy spectrum of precipitating electrons of 30–100 keV on the daysideOur sounding rocket experiment identified precipitating energetic electrons within typical resonance energy with chorus waves on the daysideGround‐based and satellite observations of chorus waves support that the observed electron precipitation was caused by chorus waves We conducted a sounding rocket experiment, which obtained detailed energy spectrum of precipitating electrons of 30–100 keV on the dayside Our sounding rocket experiment identified precipitating energetic electrons within typical resonance energy with chorus waves on the dayside Ground‐based and satellite observations of chorus waves support that the observed electron precipitation was caused by chorus waves