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A regeneratively cooled combustion chamber of a cryogenic liquid rocket engine is exposed to a large temperature difference between a combustion gas and a liquid hydrogen coolant. The large temperature difference induces large thermal stress in the chamber wall, and the strain is accumulated throughout the cyclic firing tests. Evaluation of the stress and the strain distribution in a chamber wall is essential for chamber life prediction because the chamber life is related to such stress and strain. A feasibility study on a neutron diffraction method for evaluation of residual strain distribution in a chamber wall was conducted. A method of positioning cooling channels inside a combustion chamber was established. The measurement time was adjusted to improve the fluctuation of the diffraction data. The measured data were compared with the numerical data by finite element analysis.

It is known empirically that the lightning stimulates plant growth in realm of agriculture. Furthermore, growth stimulations of pulsed power for mushrooms have been reported as well. Therefore, the application of pulsed power technology could enhance the growth of agricultural crops easily. This study examined the effects of electrical stimulation on mycelium of a fungus. Sparassis crispa. S. crispa contains a large amount of β-1, 3-glucan which has anticancer action. While there have been several experimental studies producing fruit body of fungi, we selected an experiment for mycelium of S. crispa. In case of mycelium cultivation, the culture period is shorter than fruit body and, the culture operation is relatively facile. A Blumlein-type pulse forming network (B-PFN) was used to generate electrical pulsed discharges of approximately 20 kV and 450 ns on the surface of the culture solution containing the mycelium of S. crispa. The length of discharges was approximately 14 mm. During the 10 day culture period, electrical pulse discharge treatment was applied on the second, fourth, and sixth day. The mycelium pellets were observed and metabolites were evaluated with a high-performance liquid chromatography (HPLC). The observed amount of β-1, 3-glucan in pulse-treated samples was significantly 1.22 times higher than in control samples.

The review article deals mainly with nonlinear convection (NLC) in porous media and discusses analytical and numerical techniques to handle them. A section on experimental heat transfer in porous media relates to the state of the art on the subject. Five techniques for studying NLC are presented in a logical order of traversal. The first technique, due to Lyapunov, is useful to obtain energy bounds and in conjunction with a variation technique can be used to investigate for possible subcritical instabilities. The power integral and the spectral methods concern steady finite-amplitude convection. The former method is useful in obtaining information on physically preferred cell patterns, whereas the latter can handle cross-interaction of different modes in addition to estimating heat transfer. The Fourier decomposition for unsteady large-amplitude convection is capable of predicting chaos and quantifying heat transfer. The finite-difference method, or any numerical method, when guided by the results of the existing analytical methods and experiment, can be used effectively to handle a more general problem with realistic boundary conditions. The results of the experimental and theoretical study are meant to mutually ratify the respective findings. The present scenario on heat transfer in porous media is such that not all observed aspects can be covered in a theoretical study and also not all results predicted by the theory are experimentally realizable. It thus calls for concerted effort from various quarters. It is on this ground that the review puts together many aspects of NLC in porous media, taking essential excerpts from previous works, with an unavoidable lean on the authors' own works.

Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat.We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice.Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout.These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia.

The Rayleigh-Taylor (RT) instability at the interface between fluid and fluid saturated sparsely packed porous medium has been investigated making use of boundary layer approximation and Saffmann [8] boundary condition. An analytical solution for dispersion relation is obtained and is numerically evaluated for different values of the parameters. It is shown that RT instability can be controlled by a suitable choice of the thickness of porous layer, ratio of viscosities and the slip parameter.

The swelling equilibrium of an ionic polymer gel soaked in a solution of two components has been investigated in terms of a modified Flory-Huggins model. A variety of phase diagrams are calculated for gel systems of liquid 1/liquid 2/polymer network for different values of the model parameters. It can be anticipated that gels can change their volume discontinuously even in a mixture of partially miscible liquids. In some systems, there is no critical point though a discontinuous change does take place. For gel systems of solvent/electrolyte/polymer network, calculation shows that the concentration of electrolyte inside the gel will change discontinuously at a point of discontinuous volume change. Calculation of transition points under a uniaxial swelling condition successfully explains the composition hysteresis between swelling and shrinking transitions.

A hydrophilic composite membrane for blood plasma separation has been prepared by surface graft copolymerization initiated by low-temperature plasma (LTP). After short LTP pre-irradiation onto a microporous polypropylene (PP) membrane, N-N -dimethylacrylamide (DMAA) vapor was introduced for grafting. The PP membrane had a 0.45 μm effective pore size and a 130 μm thickness. The rate of DMAA grafting onto PP was very high, even in vapor-solid phase reaction under reduced pressure; DMAA 1 mm Hg (133Pa). The percentage of grafted poly-DMAA (PDMAA) reached 15% within 5 min post graft polymerization, and the membrane surface, including the interior surface of pores, became completely hydrophilic. There was no apparent change observed in the membrane morphology in the dry state after the PDMAA-grafted layer was formed. However, water flux significantly decreased, probably due to swelling of the PDMAA-grafted layer. With a grafting yield below 17%, the PDMAA-grafted PP (PP-g-PDMAA) membrane showed a good separation capability of plasma from whole blood. The PP-g-PDMAA membrane exhibited low complement activating potential, high sieving coefficient for plasma proteins and high blood compatibility. Decreases in adsorption of blood cells, plasma proteins, and other biomolecules may be the reason for the membrane performance.

The treatment of a severe post-burn contracture of the left hand is presented. A free scapular flap was transplanted to the inguinal area and then used to release the contracture in the manner of a pedicled groin flap. The advantages of this method are that it can be utilized regardless of the condition of the recipient site, and the major vessels of the hand remain intact.

The beam source is composed of a thermal contact–ionization plasma source and an accelerating lens system. The plasma source is made of a rhenium‐foil cylinder 5 mm in diameter and it can be heated up to about 3000 K. A Li+ beam current over 500 μA has been obtained with this source. For the production of a Li− beam, an additional reservoir is attached to the source to supply Cs vapor into the plasma. The ion species can be examined by the time‐of‐flight (TOF) technique. In the case of Li+ production, ions of alkaline impurities, Na and K, in the Li metal have been observed in the TOF spectra. In the case of Li− ion production, the current intensity of negative ions also changes with the passage of operating time from K−, Na− to H− or H−2. This is also attributable to alkaline impurities in Li metal. A negative ion beam, which has been observed after the evaporation of impurities amounting to 200 nA, is very likely attributable to the Li− beam, though the corresponding TOF signal is very noisy.

We experimentally and theoretically investigate the turbulence characteristics in porous media. Experiments are made on the flow through a bank of tubes in a narrow gap to examine the microscopic turbulent field in porous media and we recognize that the flow through porous media becomes turbulent at high Reynolds number and that flow distortions due to the obstructions in the solid matrix produces additional mixing to that of the interstitial vortex. Then we introduce the concept of the eddy diffusivity which is characterized by the pseudo vortex and the void vortex, and we propose the macroscopic momentum and energy equations for the turbulent flow through porous media The present 0-equation model describes well the Forchheimer flow resistance and the thermal dispersion, and we clarify that the void vortex mainly contributes to the Forchheimer flow resistance and that the pseudo vortex mainly contributes to the thermal dispersion. Furthermore, we discuss the mechanism of the production and thermal dissipation of the turbulence in porous media and we estimate Kolmogorov’s micro-length scale.

Quantitative phase analysis of equilibrium ventriculography was performed to study the character of left ventricular (LV) wall motion abnormalities in patients with spastic angina pectoris, who may have clinically and electrocardiographically silent ischemia combined with myocardial stunning, during rest and hyperventilation stress testing.Phase analysis of the left ventricle at rest was performed by equilibrium radionuclide ventriculography in 13 control subjects and 36 patients with spastic angina pectoris. First-pass methodology along with hyperventilation stress testing was performed to assess spasm occurrences. Phase analysis of equilibrium multigated blood-pool scintigrams was performed to evaluate LV asynchrony at rest.The mean s.d. of LV phase distribution in the patients with variant and vasospastic angina was greater than that in the healthy control subjects (11.28 +/- 1.79 and 10.02 +/- 1.57 degrees versus 6.16 +/- 1.07 degrees). In addition, the mean s.d. of LV phase distribution in the variant angina group was greater than that in the vasospastic angina group. Furthermore, a linear correlation was found between the s.d. of LV phase distribution at rest and the percent decrease in ejection fraction during hyperventilation stress.Asynchronous LV contraction without significant hypokinesis was detected at rest in spastic angina pectoris. The severity of this asynchronous contraction corresponded well with decreases in ejection fraction during hyperventilation stress testing. Thus, analysis of the s.d. of LV phase distribution at rest is expected to provide useful information regarding LV asynchrony in spastic angina pectoris.

It is well known that left ventricular regional contraction abnormality (hypokinesis: hypo) occurs during myocardial ischemia. However, it is uncertain whether left ventricular asynchronous contraction (asynchrony) is an index of myocardial ischemia. To validate asynchrony as an index of myocardial ischemia, isoproterenol infusion stress (ISP) cardiac blood-pool scintigraphy (RI angiography) was performed in patients with ischemic heart disease. The subjects were classified into 2 groups: 1) 15 patients with coronary artery disease (CAD) and 2) 8 patients with "normal" coronary arteries (NC). None had any electrical ventricular conduction disturbance. ISP was administered with increasing doses of 0.02, 0.04, 0.08 microgram/kg/min at 3-min intervals, and it was terminated in the event of angina, significant ST changes or target heart rate. Symptom-limited ergometer exercise testing (EX) was also administered in 14 patients. Regional decrease in amplitude and phase delay identified by phase analysis was diagnosed as hypo and asynchrony, respectively. ISP myocardial scintigraphy was also performed in 15 patients. Results were as follows: ISP and EX induced asynchrony in 14 (93%) and 13 patients (93%), respectively, while, did hypo in 4 (27%) and 9 (64%), respectively. Ten (67%) of 15 patients had asynchrony without hypo in ISP; whereas, only 4 (28%) of 14 patients did in EX. ISP-induced asynchrony occurred in one of 8 patients with NC. The locations of ISP-induced asynchrony and those of EX-induced asynchrony were concordant in 11 (79%) of 14 patients. Asynchrony on the ISP RI angiogram was observed at the same sites of redistribution on the ISP myocardial scintigram. We concluded that asynchrony itself is a sensitive and specific index of myocardial ischemia.

The effect of aging on cardiac function in patients with right bundle branch block (RBBB) was commonly unknown, so left ventricular function and right ventricular function were investigated, using first-pass radionuclide angiography. Twenty-six patients with RBBB and 28 normal subjects were studied at rest and during bicycle exercise. Patients with RBBB but normal cardiovascular systems aged 33 to 75 years were divided into those within 60 years (n = 17) and those over 65 years (n = 9). Using the same method, normal subjects aged 38 to 83 years were divided into those within 60 years (n = 18) and those over 65 years (n = 10). Mean age between normal subjects and patients with RBBB didn't differ significantly. The response of left ventricular ejection fraction in normal groups rose during exercise, but its exercise tolerance function declined with aging. Left ventricular diastolic filling in normal groups declined at rest and during exercise with aging. Left ventricular function in RBBB groups showed the same results as those of normal groups. The response of right ventricular ejection fraction and its exercise tolerance function in normal groups was not influenced by aging. However, in contrast, right ventricular function in RBBB groups decreased with aging. We suggest that the mechanism of decrease of right ventricular function in aging patients with RBBB may be caused by the change of right ventricular contraction which is affected by the aging process.

A new dynamic model for non-Fickian diffusion of calcium spark in cardiac myocytes was developed by introducing time lags on the basis of the microscale mass transport theory. Numerical simulation showed that the size of the calcium spark produced by the new dynamic model was larger than that of Fick diffusion and was in more agreement with experimental results. In addition, the time lags of the calcium spark in cardiac myocytes were about 0.1 –0.8 ms. These results can be used to understand the mechanism of calcium spark diffusion in cardiac myocytes.

Heat transfer by a natural convection in a vertical porous layer heated from below and cooled from above is studied analytically. In the case of linear theory, the normal mode technique is used to find the criteria for the onset of convection and it is shown that convection sets in when the cirtical Reyleigh number exceeds π2. The nonlinear theory is investigated using normal mode technique combined with the orthonormal sequences which determines the amplitudes and hence the heat transfer. It is shown that uni-cellular pattern exist and the corresponding heat transfer increases with Rayleigh number.

This work reports the principle, advantage, and limitations of analytical photoion spectroscopy which has been applied to dissociative photoionization processes for diatomic molecules such as H2, N2, CO, and NO. Characteristic features observed in the differential photoion spectra are summarized with a focus on (pre)dissociation of(i) multielectron excitation states commonly observed in the inner valence regions,(ii) shape resonances, and(iii) doubly charged parent ions. Possible origins for negative peaks in the differential spectra are discussed.

The occurrence of large, intensely fluorescent (LIF) catecholamine-containing spots in the brains of mice and rats has been studied by fluorescence microscopy. LIF spots in C57BL/6J mice increased in number progressively with age. Apparent differences between sexes in the number of spots were not significant at any age. A greater number of LIF spots were present in older mice and rats of different strains indicating that LIF spot formation is neither strain nor species specific. Long-term feeding of antioxidants (ascorbic acid, α-tocopherol, and β-mercaptoethylamine) to C57BLl6J mice did not alter significantly the number of LIF spots, suggesting that age-related LIF spots are formed by a mechanism other than endogenous free radical damage.

Peripheral chemical sympathectomy by 6-hydroxydopamine in rats accelerated turnover of cerebral noradrenaline, but did not change turnover of cerebral dopamine and 5-hydroxytryptamine. This increase in noradrenaline turnover was long lasting and was observed in the first degenerative phase of the action of 6-hydroxydopamine as well as after established degeneration of the peripheral sympathetic nerves.

The biosynthesis of octopamine, p-hydrophenylethanolamine, has been studied in mice and rats. The animals were given of either p-[ 14 C ] hydroxyphenylserine or [14C]tyramine and were sacrified at various times after the injection. The octopamine was extracted separately from the urine and tissues. Authentic carrier octopamine was added before extraction. The whole carcass of each mouse was used, and the adrenals, spleen, heart, brain, and kidneys of each rat were pooled. The extracts were passed through Dowex-50 resin columns before paper chromatography. The chromatograms were exposed to X-ray film for two to three weeks before spraying and also were counted in a liquid scintillation counter. The injected p-[ 14 C ] hydroxyphenyl-serine appeared not to be decarxylated to octopamine to any appreciable extent. After the injection of [14C]tyramine, however, labeled octopamine was positively identified in both tissues and urine.

Summary The localization and distribution of [ 14 C]amphetamine in mouse brain has been studied by an autoradiographic technique and by thin-layer chromatography. Thin-layer chromatography revealed that radioactivity in the brain is chiefly due to unchanged amphetamine. The highest content was found in the cerebral cortex, hippocampus, thalamus, septum and basal ganglia. The possible relationship of this localization to the site of action of amphetamine and the distribution of catecholamine nerve terminals is discussed.

An erythrocyte plasma system was incubated with various thiols (final concentration, 0.003 M) to study the effects on protein sulfhydryl content. After timed incubation, the plasma sulfhydryl concentration, i.e. the protein and nonprotein fractions, was determined by polarographic analysis. The results indicate that sulfhydryl groups of the thiol were transferred or converted to increase the protein sulfhydryl content in the presence of tissue sulfhydryl groups. An increase of protein sulfhydryl did not take place in the absence of cellular elements and was partially inhibited by first blocking the sulfhydryl groups of the cellular elements. Studies in vivo were also conducted to determine whether the sulfhydryl groups of the thiols can be exchanged with, or converted to, tissue protein sulfhydryl groups. N -acetylcysteine was given intravenously in Swiss mice and the protein and nonprotein sulfhydryl content of various tissue fractions was assayed. Distribution studies after administration of the 35 S-labeled N -acetylcysteine were conducted utilizing autoradiographic procedures. A significant increase in the tissue protein sulfhydryl content was again achieved in vivo . These findings support the hypothesis that thiols can be utilized to increase tissue sulfhydryl groups when the latter are deficient, as reported in various clinical disorders. The approach may, therefore, have therapeutic application.

The localization of uptake 5 minutes after the injection of a low dose of 3H-norepinephrine by adrenergic nerve fibers in the heart has been observed by combining autoradiography with the formaldehyde-induced histochemical fluorescence method for aromatic monoamines in the same tissue section. The distribution of 3H-label corresponds exactly to that of the fluorescent nerves. Furthermore, uptake studies in animals depleted of catecholamines by the tyrosine hydroxylase inhibitor (H 44/68), which does not block uptake, indicate that the dosage of 3H-norepinephrine used, under the conditions of the present experiment, was not in itself sufficient to produce the intense formaldehyde-induced fluorescence in nerves. It may be concluded that 3H-norepinephrine was taken up only by those nervous structures in the heart which show a specific fluorescence reaction due to the presence of endogenous catecholamine.

A new apparatus for the study of photoionization processes has been designed and constructed. The main capabilities of the apparatus include measurements of angle‐resolved photoelectrons, as well as time‐of‐flight measurements of photoions in coincidence with total, energy selected, or threshold electrons.

THE catecholaminergic neurones of the mammalian brain are generally believed to be important in the control of voluntary behaviour and affect. The evidence for this comes from work with pharmacological agents which enhance or block the post-synaptic effects of noradrenergic or dopaminergic neurones1–3. This has led to speculations implicating central catecholaminergic dysfunction in affective disorders such as depression1,4,5 and in other disorders such as Parkinson's disease6 and schizophrenia7,8. But research on the behavioural effects in animals of pharmacological interference with the normal functions of central catecholamines has been hindered by the fact that the sudden withdrawal of either noradrenaline or dopamine leads to behavioural sedation and inactivity9–14, which precludes any fine analysis of behavioural deficits.

Brains of C57BL/6J mice, aged 4, 8 and 20--29 months, were examined by the Falck-Hillarp histochemical fluorescence technique. Numerous large, intensely fluorescent green to yellow-green spots (LIFS) were observed in the brains of senescent mice. LIFS were generally round to ovoid in shape and ranged in size from about 10 micrometer to about 30 micrometer. Histochemical and pharmacological procedures and spectral analysis indicated that the formaldehyde-induced fluorescence of the LIFS was due to the presence of catecholamines (CA) rather than aging pigment. Their distribution in the brain suggests an association with nerve axons or terminals rather than cell bodies. The number of LIFS in the hypothalamus increased progressively during aging. It is proposed that LIFS may represent age-related, unusual CA accumulation in enlargements proximal to axonal or terminal portions undergoing spontaneous degeneration.

Although phenobarbital is the most widely used drug to control seizures, dosage guidelines are not available for infants of varying gestational ages. The primary objective of this study was to develop age specific dosage guidelines for phenobarbital in newborn infants with seizures. Fifty-one patients (27 premature infants, gestational ages 27 to 38 weeks; 24 term infants) receiving phenobarbital, 3 to 6 mg/kg/d were studied during the first month of life. Multiple serum concentrations were determined in each patient during extended therapy. Trough serum concentration of phenobarbital ranged from 12.5 to 50.2 mcg/mL. Phenobarbital serum concentrations were within therapeutic range (15 to 40 mcg/mL) in 99 of 114 measurements at a maintenance dose of 3.5 to 4.5 mg/kg/d. The remaining 15 measurements were made in infants, greater than 35 weeks' gestation and required phenobarbital doses of 4.0 to 5.0 mg/kg/d to achieve therapeutic serum concentration. These data suggest that the initial maintenance dose of phenobarbital during the first month of life should be 3.5 to 4.5 mg/kg/d in infants less than or equal to 35 weeks and 4.0 to 5.0 mg/kg/d in those greater than 35 weeks' gestation. Term infants with asphyxia had higher trough serum concentration than those without asphyxia (P less than 0.005). In nine infants, trough serum concentration normalized for dose decreased substantially during a 3-weeks period (P less than 0.0005). This suggests that phenobarbital serum concentration should be monitored frequently during the first month of life.

Both LSD and apomorphine produced hyperactivity in reserpine-treated mice, LSD being more potent and longer-acting than apomorphine. 2-Brom LSD and the serotonin (5-HT) receptor agonist quipazine were ineffective in reversing reserpine sedation. Treatments with phenoxybenzamine and methysergide failed to block the stimulant effects of either LSD or apomorphine, demonstrating the noninvolvement of 5-HT or norepinephrine (NE) receptors in their action. The ineffectiveness of α-methyl-p-tyrosine in modifying the stimulant effects of LSD and apomorphine indicated a probable direct stimulant effect of these two drugs on the dopamine (DA) receptors. Low doses of chlorpromazine, haloperidol, or pimozide blocked the effects of apomorphine in reserpinized mice. Although these neuroleptics significantly reduced the effects of LSD, they failed to block completely the LSD effects even at higher doses. Apomorphine reduced the α-methyl-p-tyrosine-induced depletion of DA in the whole brain of mice, but LSD failed to do so. From these findings it is postulated that apomorphine acts as a direct DA receptor agonist, and that LSD may act directly on a site structurally closely related to DA receptor, but not necessarily identical with it. Repeated treatments with LSD did not lead to development of tolerance to its locomotor effects in reserpinized mice. Moreover, mescaline and psilocybin, which are known to exhibit cross-tolerance to LSD, failed to produce LSD-like effects in reserpine-treated mice. The effects of LSD on the DA or a related site probably are not solely responsible for its psychotomimetic effects.

Adult rats were injected intraventricularly with 6-OHDA and allowed to recover for varying time periods in either an enriched colony environment or in isolation cages. When tested behaviorally in a novel environment, isolated animals showed a cyclical recovery pattern, with behavioral changes at 14 days after lesioning which were different from those seen at 2 and 45 days after lesioning. In contrast, animals housed in a colony environment showed progressive improvement and better recovery than isolates. Biochemical studies of uptake of H3NE and histofluorescence indicated that colony housed animals had enrichment effects (higher cortical NE uptake), but they were also more susceptible to 6-OHDA and did not recover well from the lesions. Isolated animals showed somewhat better recovery of NE uptake following 6-OHDA injections, especially in cortex. Because behavioral recovery from 6-OHDA was dissociated from biochemical indicators of recovery in NE circuitry, these results imply that brain systems other than NE were primarily responsible for the enhanced behavioral recovery which occurs in enriched environments.

The injection of reserpine, 5 mg/kg i.p. (ipRes), the regimen employed by a majority of investigators, results in synaptosomal and vesicular preparations which are incompletely reserpinized as determined by [3H]dopamine ([3H]DA) accumulation. Reserpine administered by the subcutaneous route, 5 mg/kg (scRes), appears to produce complete reserpinization. Release of [3H]DA by d-amphetamine (Amph) was observed from striatal synaptosomes prepared both from normal rats and those pretreated with reserpine intraperitoneally but not from those injected subcutaneously. In the more completely reserpinized scRes synaptosomes, so little [3H]DA had accumulated that release by Amph was not measurable, indicating that if a labile, reserpine-resistant, extravesicular DA storage pool releasable by Amph is present under these conditions, it must be extremely small. In scRes monoamine oxidase (MAO)-inhibited preparations, Amph released preloaded [3H]DA located in the cytosol in the absence of functional vesicles. Although chromatographic analysis of the superfusate from ipRes striatal synaptosomes showed that significant amounts of preloaded [3H]DA were released by Amph, the level of dihydroxyphenylacetic acid was not increased over controls, indicating that Amph releases only DA and not its metabolite and is also acting as a MAO inhibitor. No [3H]DA could be released by Amph from superfused hyposmotically shocked normal or ipRes synaptosomes, suggesting that an intact membrane is required for Amph-induced release.

The value of exercise thallium scintigraphy in detecting coronary artery disease is well established. However, there are at times situations in which the exercise test cannot be readily used. Isoproterenol (ISP) stress ECG (ISP-ECG) is reportedly a useful method in diagnosing coronary artery disease. In the present study, we assessed the diagnostic value of ISP thallium scintigraphy, comparing it with those of ISP-ECG and exercise thallium scintigraphy. The study population consisted of 24 patients who had histories of chest pain without previous myocardial infarction. ISP was given at increasing doses of 0.02, 0.04, 0.08 micrograms/kg/min at 3-minute intervals, and was terminated for any of the following reasons: angina, significant arrhythmia, significant ST segment depression (greater than or equal to 0.1 mV) or target heart rate. Thallium scintigrams were obtained immediately after terminating ISP infusion, and after a 3-hour delay, redistribution scans were obtained. Scintigrams were considered positive when a reversible defect was present. In nine patients who underwent exercise tests, exercise thallium scintigraphy was also performed. After the stress tests, coronary angiography was performed. According to the presence or absence of significant coronary artery stenosis (greater than or equal to 75%), all subjects were divided into two groups: coronary artery disease (CAD) group (n = 12) and so-called normal coronary (NC) group (n = 12). 1. Among 12 patients in the CAD group, ISP induced anginal pain in six (50%), and ISP-ECG and ISP thallium scintigraphy were positive in 10 (83%) and in 11 (92%), compared with four (33%), four (33%) and two (17%) in the NC group.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of early myocardial reperfusion (within six hours after the onset of symptoms) on left ventricular (LV) function in 106 patients with acute myocardial infarction was studied. The subjects consisting of 26 with conventional therapy, 19 with percutaneous transluminal coronary recanalization (PTCR), 16 with percutaneous transluminal coronary angioplasty (PTCA) after PTCR, 32 with direct-PTCA and 13 with coronary artery bypass graft (CABG) were randomly observed after 1981. In these patients, left ventricular ejection fraction (LVEF), regional wall motion, end-diastolic pressure and the contractility index were measured as the indices of LV function. 1. Compared to the conventional therapy group, LVEF and regional wall motion improved significantly in all groups with reperfusion therapy except in the PTCR group. This LV function in patients with subtotal obstruction or good initial collaterals significantly improved compared to patients with total obstruction and no collateral circulation. Patients with a 75 percent or more residual stenosis after reperfusion therapy had significantly decreased LV function compared to those with residual stenosis of less than 75 percent. These findings support the potential role for reperfusion therapy in patients with acute myocardial infarction.

Serum squamous cell carcinoma (SCC) antigen levels were measured in 55 patients with lung cancer, 43 with benign diseases and 50 normal subjects. At the same time, carcinoembryonic antigen (CEA) was measured for comparison. The mean SCC antigen levels were 1.47 + 0.50 ng/ml in 50 normal subjects. The percentage of positive case for SCC antigen (higher than 2.6 ng/ml) was 27.8% in lung cancer as a whole, 17.6% in adenocarcinoma, 47.6% in squamous cell carcinoma, 6.7% in small cell carcinoma and none in large cell carcinoma. Fifty percent of the Stage II patients were positive for SCC antigen, and the assay might be a possibility for early diagnosis. Our study suggests that SCC antigen assay may be a useful test for the identification and evaluation of lung cancer patients.