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Kerr-lens mode-locked Cr:LiSrAlF/sub 6/ lasers are demonstrated with various prism pairs based on a recalculation of the condition for compensating the intracavity dispersion. The minimum pulse duration is 9.9 fs, which is the limit for ordinary nonchirped dielectric mirrors. To develop an efficient diode-pumped Kerr-lens mode-locked Cr:LiSAF laser, diode-pumping geometry is also discussed.

The high pressure effect on resistance of the LB film of ditetradecyldimethylammonium-Au(dmit)2 [2C14N+Me2-Au(dmit)2] salt has been investigated; the measurements were performed down to 0.8 K and pressures up to 1.03 GPa using a clamptype pressure cell. The resistance gradually decreases with increasing pressure reaching a 57% smaller value at 1.03 GPa compared to the ambient one. The resistance increases with decreasing temperature for three different conditions of the measurement: at 0 GPa and under pressure (clamped at 0.80 GPa and 1.03 GPa) in the temperature range of 18−295 K. Over the whole temperature range, the higher the pressure is, the lower the sheet resistance is, indicating that the application of pressure is effective to reduce the sheet resistance. Although we have already reported the magnetic anomaly suggesting the Meissner state in the LB film below 3.9 K, no resistance drop is observed even if the resistance was measured down to 0.8 K.

Effects of a kampo (Japanese herbal) medicine "kami-untan-to (KUT)" on central cholinergic neurons were examined in vitro and in vivo. When rat embryo septal cells were cultured in the presence of KUT (50-500 μg/ml) for 3 days, significant increase of choline acetyltransferase (ChAT) activity was observed. However, KUT had no significant effect on nerve growth factor (NGF)-induced ChAT activity in basal forebrain cultures. When KUT was orally administered to the ibotenic acid-induced forebrain lesioned rats, mean latency was significantly increased on passive avoidance of step through type and ChAT activity in cerebral cortex was also increased. These results indicate that KUT is a neurotrophic-like agents which is effective to the cholinergic nervous system and may be useful as a potential therapeutic agent in diseases exhibiting cholinergic deficit.

A wave-acoustics theory has been developed to describe the propagation of zero sound parallel to vortex lines in rotating 3 He-A. We show that a diffraction «shadow» is formed in which the wave amplitude is suppressed by interference around vortices. This phenomenon contributes to the experimentally observed effect of rotation on the sound amplitude and exceeds the attenuation at large core radii. The dependence of the diffraction contribution on the angular velocity changes drastically at the transition from vortices with a finite core to foreless vortices when the magnetic field is decreased to zero

We have observed in superfluid {sup 3}He-{ital B} two-phonon absorption, which is one of the nonlinear effects recently predicted by McKenzie and Sauls. The {ital J}=2{sup +} real squashing mode was excited with two coincident sound pulses at the temperature {ital T}{sup +}, f{sub signal}+{ital f}{sub pump}={ital f}{sub rsq}({ital T}{sup +}), under 0, 2.7, and 3.5 bars pressure. The heights of the attenuation peaks scale almost linearly with the energy of the higher-intensity wave, in qualitative agreement with the theory. Furthermore, a satellite peak appears even in zero magnetic field, which originates from the reflected wave.

Vortices in {sup 3}He-{ital A} in low magnetic fields ({ital H}{le}20 mT) have been studied by ultrasonics. A first-order phase change between two vortex types, with dissimilar sound absorption, has been found. The magnetic field at the transition is on the order of the dipolar field {ital H}{sub {ital d}}. The observed change occurs between continuous vortex textures with different topological charges in the {bold {cflx d}} field (where {bold {cflx d}} is the magnetic anisotropy vector).

Zero sound attenuation at 8.9 and 26.8 MHz in {sup 3}He-{ital B} shows an extremum at {ital T}{sub {ital AB}} in a field of {approx}2 kG at low pressures, both in the stationary and in the rotating superfluid. This is in accordance with the prediction that a critical magnetic field separates two types of {ital B} phases at the {ital AB} transition line, with and without nodes in the energy gap, respectively, and with a change in the nature of the transition. The {ital AB} phase transition takes place via an intermediate state, possibly a new phase, characterized by excess sound attenuation.

Rotation of superfluid $^{3}\mathit{B}$ in an magnetic field enhances the coupling of the nonzero ${\mathrm{m}}_{\mathrm{J}}$ substrates of the real squashing collective mode to the zero sound, and the fivefold line splitting becomes observable even when H is parallel to \ensuremath{\Omega} and to the direction of sound propagation. Equilibrium vortex lattices and vortex-free states can be distinguished by their characteristic absorption spectra. The dependence of the sound attenuation on the angular velocity in magnetic fields up to 32 mT is reported; the data are qualitatively compared with theory.

The existence of Ca2+-activated, phospholipid-dependent protein kinase (protein kinase C), the effect of gastrin on phospholipid metabolism and guanylate cyclase activity were investigated to elucidate the cellular mechanism of action of gastrin on the corporal mucosa of the canine stomach. Protein kinase activity was determined by measuring the incorporation of [32P] into calf thymus H1-histone from [32P]-ATP. One unit of protein kinase was defined as the amount of enzyme which incorporated 1 pmol of phosphate from ATP into H1-histone. Protein kinase C was found in 100,000xg supernatant of homogenate fractionated by a DEAE-cellulose column chromatography. Characteristics of further purified protein kinase C, such as dependency on divalent cations and phospholipids, were in agreement with those of previously reported protein kinase C in other tissues. Furthermore, the gastric corporal mucosa was found to contain protein kinase C in large quantities. The specific activity of protein kinase C was 26,000 units/mg protein. The phospholipid metabolism was evaluated by the incorporation of [14C]-glycerol-3-phosphate and the change of the radioactivity of [32P] in individual phospholipids. Each phospholipid was extracted from the gastric corporal mucosa and isolated by thin layer chromatography. Guanylate cyclase activity was determined by measuring the cGMP produced, using radioimmunoassay. Gastrin significantly increased the incorporation of [14C]-glycerol-3-phosphate into phosphatidylethanolamine in the presence of acetylcholine (Ach). Ach increased the uptake of the tracer into phosphatidylinositol significantly, and the increase was enhanced by the simultaneous addition of gastrin. In the experiments with [32P]-labeled phospholipids, gastrin increased the incorporation of [32P] into phosphatidylethanolamine significantly. The significant increase of the radioactivity in phosphatidylinositol by Ach failed to be enhanced by gastrin, but that of phosphatidylethanolamine by Ach was enhanced by gastrin. No stimulation of guanylate cyclase activity by gastrin was detected in the dispersed gastric corporal mucosal cells. These results indicate that gastric corporal mucosa was one of the most abundant tissues in which protein kinase C was contained, when compared with various mammalian tissues previously reported by Minakuchi, Nishizuka, et al. Nishizuka et al, recently proposed the novel hypothesis that phosphatidylinositol turnover activated by cAMP-independent agonists will be essentially required to activate protein kinase C. Our results suggest that gastrin can provoke phospholipids turnover including phosphatidylinositol turnover in gastric corporal mucosa. Therefore, our data indicate the possibility that the protein kinase C system plays an important role in the cellular mechanism of action of gastrin on gastric corporal mucosa.

Bleomycin, an anticancer drug, was labeled with 99mTc using stannous chloride and ascorbic acid and specific activities of 1-3 mCi/mg-eq with labeling efficiencies of 50-75% were achieved. Very rapid excretion of 99mTc-bleomycin through the kidney and concomitant rapid decrease of radioactivity in blood, various tissues and organs, and whole body were observed after intravenous administration of the radiopharmaceutical into tumor-bearing mice. In such animals, approximately 1% of the label was found in a transplanted fibrosarcoma within 30 min while 0.58% was recovered in such lesions even after 24 hr. In patients positive tumor images were obtained by scintigraphy as early as 1 hr after intravenous administration of 3-5 mCi of 99mTc-bleomycin. A total of 142 cases were examined by scintigraphy after administration of 99mIc-bleomycin and/or 67Ga-citrate. In 93 cases with various malignant tumors, tumor was detected in 80% using 99mTc-bleomycin and in 63% using 67Ga-citrate. Technetium-99m-bleomycin scintigraphy successfully detected tumors of the thyroid, lung, face, breast, extremity, and digestive tract and was also useful in finding metastatic lesions and brain tumors. However, 67Ga scintigraphy gave superior results in detecting lesions in patients with malignant lymphomas. In patients with inflammatory diseases, accumulation in lesions was detected in 13% using 99mTc-bleomycin and in 48% using 67Ga-citrate. The further use of 99mTc-bleomycin scintigraphy for tumor detection in patients appears to be warranted.

Dynamic positron computed tomography (PCT) of the heart was performed with a high-sensitivity, whole-body multislice PCT device and [13N]ammonia. Serial 15-sec dynamic study immediately after i.v. [13N]ammonia injection showed blood pool of the ventricular cavities in the first scan and myocardial images from the third scan in normal cases (n = 4). In patients with myocardial infarction (n = 8) and mitral valve disease (n = 2), tracer washout from the lung and myocardial peak time tended to be longer, suggesting presence of pulmonary congestion. PCT delineated tracer retention in the dorsal part of the lung. Serial 5-min late dynamic study in nine cases showed gradual increase in myocardial activity for 30 min in all normal segments and 42% of infarct segments, while less than 13% activity increase was observed in 50% of infarct segments. Thus, serial dynamic PCT with [13N]ammonia assessing tracer kinetics in the heart and lung is a valuable adjunct to the static myocardial perfusion imaging for evaluation of various cardiac disorders.

Indium-111-(111In) labeled monoclonal antibodies (Ab) prepared with a bifunctional chelating agent, diethylenetriaminepentaacetic acid (DTPA), have been used for the radioimmunoimaging of cancer. In the present experiment, using monoclonal Ab against human alpha-fetoprotein (AFP) as a model, we have studied the effect of DTPA conjugation on the antigen binding activity and the biodistribution in nude mice transplanted with AFP-producing human testicular tumor. In Ab heavily conjugated with DTPA, the Scatchard plot analysis demonstrated that the maximum binding capacity rather than the affinity constant was affected. Under selected conditions, 111In-labeled Ab were made available with almost full retention of the antigen binding activity and scintigrams of nude mice clearly delineated the site of the tumor. However, the number of DTPA molecules incorporated per Ab molecule markedly influenced the in vivo biodistribution as well as the in vitro antigen binding activity.

The effect of low sensitivity areas or gaps between adjacent slices of the multislice positron emission tomography on detection of myocardial perfusion abnormality with 13NH3 was evaluated segmentally in 36 patients with coronary artery disease at rest or during exercise. The detectability of the defects in RCA or LAD region was 80% in single-position scans in stress studies. The false-negative defects were located mainly in the inferior wall, apicoinferior wall, or high anterior wall. When the patients were moved half the slice interval to perform the interpolating scan, and the two sets of images were interlaced with each other, the detectability increased to 88%. The interpolating scan also allowed reconstruction of long-axis and short-axis tomograms in high quality, which further improved the detectability of perfusion defects (100% for RCA or LAD and 75% for LCX lesion) and helped in understanding the anatomic relationships to the coronary artery territories.

We evaluated emission computed tomography (ECT) for thallium-201 (201TI) myocardial imaging in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar 201TI perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of 201TI perfusion defects, the infarct area in planar images and the infarct volume in reconstructed ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r = 0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r = 0.69; for the largest infarct area, r = 0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS.

By the use of xenon-133 and a scintillation camera with digital data storage and processing system, a topographic relationship between ventilation distribution (V) and perfusion distribution (Q) was examined quantitatively in two groups of normal nonsmokers and one of older smokers, all healthy. In addition, subjects with a variety of cardiopulmonary disease were tested. The fractional regional ventilation (VR) and regional perfusion (QR) were plotted against the V/Q ratio on a logarithmic abscissa for the normal subjects; both were distributed log-normally with a narrow standard deviation, and were dissociated slightly from each other. However, with smoking and with increasing age, the s.d. and the dissociation became wider, suggesting an impairment of gas exchange as estimated by alveolar-atrial gas-pressure differences (A-aD), which were calculated by putting these topographic relationships into a gas-exchange program in a computer. In various cardiopulmonary diseases a good correlation was found between the estimated A-aDO2 thus obtained and the actual A-aDO2 derived from analysis of the blood gases.

Monoclonal antibodies HBJ127 and HBJ8, raised against T24 human bladder cancer cells, predominantly react with the cells in proliferating stages and with a portion of epithelial tumor cells, respectively. To investigate the in vivo localization of these monoclonal antibodies, the antibodies were labeled with radioiodine and indium-111 (111In) and injected into nude mice transplanted with human bladder tumors. The BT-11 bladder tumor had the highest concentration of radioiodinated HBJ127 and HBJ8 monoclonal antibodies, with 11.6 and 14.3% of the injected dose per gram and with a tumor-to-blood ratio of 2.6 and 1.6, respectively, at 4 days after the administration. An irrelevant monoclonal antibody did not show any specific accumulation in the BT-11 tumor. The 111In-labeled HBJ127 antibody was also localized in the tumor with a higher tumor-to-blood ratio than the radioiodinated antibody. The xenografted BT-11 tumor was successfully visualized with the radiolabeled HBJ127 and HBJ8 antibodies by scintigraphy. These monoclonal antibodies and the human bladder tumor xenografts may provide a good model for radioimmunoimaging and possibly therapy.

Basic and clinical evaluation of thallium single-photon emission computed tomography (SPECT) using a rotating gamma camera with 180 degrees (LPO to RAO) data collection was carried out and compared with the full 360 degrees rotation. No attenuation correction was used. In a phantom study the reconstructed image from the 180 degrees scan revealed better resolution. Although the 180 degrees scan, when compared with the 360 degrees scan, showed great photon attenuation in the deep location of a line source in water, this problem was not significant in the clinical study of six normal hearts. In 11 cases with myocardial infarction, the perfusion defect was more clearly visualized in the 180 degrees scan. The defect-to-normal (D/N) wall-count ratio was lower in the 180 degrees scan (0.48 +/- 0.16; mean +/- s.d.) than in the 360 degrees scan (0.61 +/- 15, p less than 0.05), indicating superior lesion contrast in the former. These results suggest that for myocardial SPECT the 180 degrees collection method is a more effective technique in the clinical evaluation of coronary artery disease.

A new quantitative method, "Simultaneous Exponential Equation method" (SEE), has been developed for the analysis of pulmonary ventilation studies using 13N-labeled nitrogen gas and positron emission computed tomography. This method uses Kety's model assuming insolubility of nitrogen gas in blood or tissues. Activity in poorly ventilated regions does not reach the equilibrium in the so-called equilibrium scan (EQ) performed following 3 or 4 min of washin. Therefore EQ images do not represent lung volume images nor do they provide the initial value of washout phase. Our method corrects for these transient phenomena observed during EQ scan and yields idealistic equilibrium state images (lung volume images) as well as more accurate regional ventilatory time constants than a modified Stewart-Hamilton (A/H) method and tomograms of high resolution.

Dynamic PET using [13N]ammonia was performed in patients with primary hepatocellular carcinoma (hepatoma). All the tumors started to show remarkable accumulation of radioactivity from a very early period (within 150 sec after the radionuclide injection), whereas the radionuclide was more gradually accumulated in the liver. Central necroses of the tumors were visualized as low radioactivity areas. Daughter nodules of less than 2 cm were also visualized. This dynamic PET study is a valuable technique for the detection of the hepatoma.

In order to obtain spatial distribution of an index for regional blood flow at each element on a scintigraphic image of the kidney, we attempted the construction of the so-called functional image. After injecting a single bolus of 133Xe into a renal artery by means of a catheter, this objective was accomplished using digital computer processing for a sequence of scintillation camera recordings of the following washout process from the kidney. This is expressed in a form of matrix of disappearance rate constant. Calculation for the rate constant, the flow index of the functional image, was done using either the least squares (LS) method or height-over-area (H/A) method. Although the former method was considered to be theoretically suitable without undue participation of background activities, the latter was preferred because of stable results for image construction. On reviewing the functional image thus obtained from 22 patients representing a variety of renal diseases, the H/A gave specific information concerning regional distribution of the perfusion integrity mainly related to the cortical part of the kidney. This is often difficult to accomplish utilizing the conventional method of compartmental analysis of the xenon washout curve or selective renal angiography.

A lung scan using 51Cr-labeled erythrocytes in a patient with Goodpasture's syndrome revealed radioactivity in the lung due to massive intrapulmonary hemorrhage.

A new efficient method has been developed for the labeling of various biologically important proteins with radiogallium, using deferoxamine (DF) as a bifunctional chelating agent. Human serum albumin (HSA) was chosen for studying the DF coupling reaction by a glutaraldehyde two-step method. The DF-HSA conjugate obtained was then easily labeled with Ga-67 with high efficiency and reproducibility. High stability of the Ga-67 DF-HSA was observed both in vitro and in vivo. In rats the half-time of blood clearance at the first phase was 234 min for the Ga-67 DF-HSA, whereas most conventional I-131 HSA gives 121 min. The excellent pharmacological and physiological properties were assessed by plasma clearance and plasma volume measurements in normal volunteers. Even at 2 hr after injection, (90.0 +/- 3.0)% of Ga-67 DF-HSA was retained within the vascular space. The mean plasma volume per kilogram of body weight, measured with Ga-67 DF-HSA, was 46.6 +/- 3.4 ml/kg, compared with 52.2 +/- 2.4 ml/kg as determined with I-131 HSA in the same men.

A technique is described for transaxial imaging of the thorax during pulmonary perfusion study. The contours of the air-containing lungs were obtained by gamma-ray transmission data from a Tc-99m plane flood source. These images were overlaid on the emission tomogram of the pulmonary blood flow obtained with Tc-99m MAA. It permits reliable detection of peripheral perfusion defects. Use of the results from these measurements can be applied to evaluate marginal hypoperfusions of the lungs.

Single-photon emission computed tomography (SPECT) for thallium-201 myocardial imaging with a rotating gamma camera was evaluated in comparison with planar imaging and seven-pinhole tomography (7P). Cardiac phantom studies indicated that defects 2 cm in diameter can be visualized by both tomographic methods, but the 7P method showed propagation of the image into nearby planes, with lower image contrast. In a clinical study of 47 patients with myocardial infarction, both sensitivity and specificity for the SPECT system were high (96 and 89%, respectively); the 7P system, on the other hand, showed good sensitivity (93%) but poor specificity (68%), while planar imaging performed conversely (75 against 89%). The overall accuracy was not significantly improved in the 7P method (planar: 81%, 7P: 83%, and SPECT: 94%). Our study indicates that SPECT, which can reconstruct reliable tomographic sections in either the transaxial, frontal, or sagittal planes, will result in a remarkable improvement in the clinical evaluation of ischemic heart disease.

Synthetic motilin caused a dose-dependent contraction on isolated rabbit intestinal segments, including the duodenum, ileum, and rectum. The contraction of duodenum was significantly greater than that in the ileum or rectum. In the duodenum, motilin was approximately 100 times as potent as acetylcholine on molar basis. The motilin-induced contractions were not influenced by atropine, chlorpheniramine, cimetidine, phentolamine, propranolol, cinanserin, 1-sar-8-ala-angiotensin II, or aspirin. Motilin did not affect the contraction induced by transmural electrical stimulation or acetylcholine. The response to motilin was unaffected by acetylcholine. Removal of Ca++ from bathing media or verapamil suppressed the motilin-induced contractions to a significantly greater extent than the contractions induced by acetylcholine. Thus, it may be concluded that motilin produces intestinal contractions by acting directly on smooth muscles, but not by acting on pharmacologically known drug receptors nor by releasing neurotransmitters such as endogenous acetylcholine. Motilin does not appear to modify autonomic nerve functions.

Studies on peripheral metabolism of simultaneously administered 125-I-labeled L-thyroxine ([125-I]T4) and 131-I labeled L-trilodothyronine ([131-I]T3) were performed in five normal subjects, in four patients with untreated hypothyroidism, and in 3 hypothyroid patients made euthyroid by the administration of T4. The fractional turnover rate (lambda 03) of thyroid hormones irreversibly leaving the site of degradation and the volumes of pool 1 (serum V1) of pool (interstitial fluid, V2), and of pool 3 (all tissues, V3)were obtained by using a three-compartment analysis. In addition to the turnover studies, the ratios for the in vivo T4 to T3 conversion were determined by paper chromatographic study in sera obtained 4, 7, and 10 daysafter the injection. The rate (K12) of the extrathyroidal conversion of T4 to T3 was also estimated by the compartment analysis. The T3 distribution volume (V3) of pool 3, in which T3 is utilized and degraded, was about 60% of totaldistribution volume (V=V1+V2+V3) in normal subjects, whereas only about 25% of the extrathyroidal T4 pool was in the intracellular compartment, indicating that T3 is predominantly an intracellular hormone..

In patients with osteoarthritis of the hip, technetium 99m pertechnetate was injected into the hip joint cavity under fluoroscopy, and the clearance was measured by scintillation counter.An obvious correlation with the clinical and roentgen findings was seen in the slope ratio of the radioisotope clearance rate when affected and healthy sides were compared.In prearthrosis and initial arthrosis, the slope ratio was usually more than 1.0 indicating a relative increase in the clearance rate on the affected side, while in advanced and terminal arthrosis, the slope ratio was usually less than 1.0 indicating a relative decrease in the clearance rate on the affected side.