Extravascular iodine in contrast enhancement with computed tomography

Using specimens obtained at operation, tissue-blood ratios of iodinated contrast material (iodine), and in some cases also those of red blood cell tracer (51Cr), were measured in 23 patients with various kinds of intracranial mass lesions. Results provided confirmatory evidence on the major role played by extravascular iodine in the positive enhancement effect with computed tomography.

Computed tomography with giant intracranial aneurysms

Five patients with giant intracranial aneurysms were studied by computed tomography. Secondary intracranial changes such as hemorrhage, cerebral infarction and communicating hydrocephalus are easily demonstrated by computed tomography. In addition, computed tomography provides precise information concerning the actual size and location of large but partially thrombosed or calcified aneurysm to better advantage than angiography.

Effect of cyclic AMP on placental active transport of amino acid in rats

In pursuit of the probable relationship of cAMP to the placental active transport of amino acids as suggested by our previous human data, experiments were done in this study with dibutyryl cAMP and theophylline loaded in pregnant rats to examine the changes in level of 14C-lysine in the maternal liver, placenta and fetus. The results are: (1) Loading of dibutyryl cAMP had no effect on the uptake of 14C-lysine in the maternal liver, placenta or fetus, except that the correction of the values with its concentration in the maternal blood revealed only a slightly significant elevation in the value in each of them 30 min after the loading. (2) Loading of theophylline significantly increased the uptake of 14C-lysine in all these organs. (3) The content of cAMP in the placenta significantly increased with the loading of theophylline. These results have led the authors to believe that endogenous cAMP is significantly linked with the placental active transport of amino acids, though there is no apparent contribution to it by exogenous cAMP.

Enzymological properties of pantothenate synthetase from Escherichia coli B

Following a previous report on physicochemical properties, the enzymological properties of a homogeneously purified preparation of pantothenate synthetase were described. The optimum pH was 10.0 and optimum temperature 30 degrees C. The lyophilized enzyme was very stable on standing at -20 degrees C. K+ or NH4+ and Mg2+ were required as activators; other cations examined were inhibitive to various extents and the enzyme required ATP as the energy supplier. Some omega-amino acids exerted strong inhibition, and the enzyme was inhibited by some chelating agents but was not affected by SH compounds and SH inhibitors. Apparent Km for pantoate was 6.3 x 10(-5)M, for beta-alanine 1.5 x 10(-4)M, and for ATP 1.0 x 10(-4)M. According to the method of Cleland, the enzyme reaction proceeds by a Bi Uni Uni Bi Ping Pong mechanism and a scheme showing the order of binding of substrates and releasing of products is presented.

CT cisternography with intracranial arachnoidal cysts

Four patients with an intracranial arachnoidal cyst studied by computed tomography are reported. On the routine CT scan, arachnoid cysts are well defined lesions with the same density as cerebrospinal fluid and are not enhanced with contrast. Metrizamide CT cisternography further provides precise anatomic and physiologic information which may be difficult to obtain by angiography or air encephalography.

Periventricular lucency in hydrocephalus on computerized tomography

The ventricular margin on computerized tomography (CT) was examined in patients with dilated ventricles. In childhood and adult hydrocephalus of various causes, periventricular lucency of several degrees was often detected in the frontal horn, when hydrocephalus had progressed to an advanced stage. Since the periventricular low density zone disappears in a short time after a shunting operation, together with a reduction of the ventricles to normal size, the lucent zone around the ventricles may represent an increase in water content in periventricular white matter. This is consistent with periventricular edema, rather than loss of lipids and proteins.

Antigenic competition in the induction of contact sensitivity in mice

Antigenic competition in contact sensitivity was found to occur between DNFB and PCl and also between some other pairs of non-cross reacting sensitizers. When mice were painted with DNFB 0-7 days before the sensitization with PCl, the responsiveness to PCl was suppressed completely, whereas when DNFB was painted after sensitization with PCl, the responsiveness to PCl was affected. The prior application of DNFB resulted in the reduction of DNA synthesis in the draining lymph nodes of PCl-sensitization. This indicated that the suppression by painting with DNFB was not attributable to the inactivation of PCl-specific effector T cells which had already been generated by the sensitization with PCl, but to the inhibition of the generation of PCl-specific effector T cells. The antigenic competition occurred even when two contact sensitizing agents were applied to different lymphoid regions of mice. The suppressive effect of DNFB on the PCl-sensitization was observed also in the mice which had been made tolerant to DNFB. These results seem to imply that the antigenic competition in the present experimental system is the phenomenon which may not be mediated by effector T cells but rather by other cells, possibly suppressor cells.

Computerized tomography in Moyamoya syndrome

Twelve patients with Moyamoya syndrome were examined by computerized tomography (CT); nine children and three adults. In one patient, CT was normal. Significant abnormalities on the precontrast CT in the remaining 11 patients were: cortical atrophy with or without varying degree of ventricular dilatation, and irregularly shaped, various sized, often multiple or bilateral lucent foci in the cortex, subcortical white matter and the central gray matter. After contrast enhancement, no significant increase in the attenuation number was observed in and around the lucent foci except in one patient. In three patients, there was a slight increase in density in the central gray matter, however the increase in density was slight when the dense angiographic vascular networks in the basal ganglia were considered.

Two omega-amino acid transaminases from Bacillus cereus

Bacillus cereus strain K-22 produced two distinct omega-amino acid transaminases, one catalyzing the transamination between beta-alanine and pyruvic acid and the other that between gamma-aminobutyric acid and alpha-ketoglutaric aic. The two enzymes were partially purified and separated from each other by various chromatographies. beta-Alanine:pyruvic acid transaminase and gamma-aminobutyric acid:alpha-ketoglutaric acid transaminase were induced by the addition of beta-alanine and gamma-aminobutyric acid, respectively, to the growth medium. beta-Alanine transaminase showed an optimum pH of 10.0 and optimum temperature of 35 degrees C, and its Km values for beta-alanine and pyruvic acid were both 1.1 mM. gamma-Aminobutyric acid, epsilon-aminocaproic acid, 2-aminoethylphosphonic acid, and propylamine showed about 30-40% of the activity of beta-alanine as amino donors, and oxalacetic acid was as good an amino acceptor as pyruvic acid. The optimum pH and temperature of gamma-aminobutyric acid transaminase were 9.0 and 50 degrees C, respectively, and its Km value for gamma-aminobutyric acid was 2.8 mM, while that for alpha-ketoglutaric acid was 2.3 mM. gamma-Aminobutyric acid and delta-aminovaleric acid were good amino donors but other omega-amino acids were virtually inactive with gamma-aminobutyric acid transaminase; alpha-ketoglutaric acid, and to a lesser extent glyoxylic acid, were active amino acceptors. Sulfhydryl reagents specifically activated gamma-aminobutyric acid transaminase.

Feto-maternal amino acid patterns and cyclic AMP in the human placenta with abnormal pregnancies, particularly with SFD

To clarify the causes of SFD from the view-point of placental function, investigations were made on feto-maternal amino acid circumstances and on how cyclic AMP behaves in the placenta, particularly in relation to the transport of amino acid across the placenta. Amino acids were measured by gas liquid chromatography (hydrogen-flame ion detector), c-AMP by the binding protein method, adenyl cyclase activity by Krishna's method, and proteins by Lowry's method. Results show: (1) The levels of maternal amino acids were indistinctive between the SFD group and the normal pregnancy group. (2) The feto-maternal ratio of amino acid concentrations (f/m ratio) was lower in the SFD group than in the normal control. (3) The level of c-AMP in the placenta was lower in the SFD group than in the control. (4) The lower level of placenta c-AMP in the SFD placenta seems partly attributable to the decreased adenyl cyclase activity. (5) There was a positive correlation (gamma=0.61) between the content of c-AMP in the placenta and the f/m ratio of amino acid concentrations. These findings suggest a decline in placental active transport of acids in SFD; adenyl cyclase and c-AMP in the placenta presumably play a key role in such course.

Separation and properties of the NAD-linked and NADP-linked isozymes of succinic semialdehyde dehydrogenase in Euglena gracilis z

Euglena gracilis z contained two succinic semialdehyde dehydrogenases (EC 1.2.1.16), one requiring NAD and the other NADP, and these isozymes were separated from each other and partially purified. The NAD-linked isozyme was relatively stable on storage at 5 degrees C whereas the NADP-linked one was extremely unstable unless 30% glycerol or ethyleneglycol was added. The optimum pH was 8.7 and optimum temperature 35-45 degrees C for both isozymes. They were inhibited by Zn2+ and activated, particularly the NAD-linked enzyme, by K+. Sulfhydryl reagents activated both isozymes. The Km values for succinic semialdehyde were 1.66 - 10(-4) M with the NAD-linked isozyme and 1.06 - 10(-3) M with the NADP-linked one. The NADP-linked isozyme was induced by glutamate while the NAD-linked one was not. Probable roles of these isozymes in the physiology of Euglena gracilis are discussed.

Pantothenate synthetase of Escherichia coli B. I. Physicochemical properties

Using a new apparatus for preparative polyacrylamide gel electrophoresis, pantothenate synthetase (D-pantoate: beta-alanine ligase (AMP-forming), [EC 6.3.2.1] was purified about 500-fold from Escherichia coli B. It was found to be homogeneous in analytical disc gel electrophoresis and sedimentation ultracentrifugation (so20, w=4.9). From sedimentation equilibrium ultracentrifugation, a molecular weight of 70,100 was obtained, which is in good agreement with the value obtained by the Sephadex G-150 gel filtration method (69,000); the diffusion constant was calculated to be 5.88X10(-7) cm2/sec. The minimum molecular weight calculated from the amino acid composition of this enzyme protein was 19,700, a value in reasonable accord with molecular weight of the enzyme subunit, 18,000, obtained by gel electrophoresis in the presence of sodium dodecylsulfate. The partial specific volume, v, was calculated to be 0.71 cm3/g. The enzyme had an amino-terminal glycyl residue and a Leu-Ala-Ser-OH sequence at the carboxyl end. Electrophoresis of the enzyme with carrier ampholine gave an isoelectric point of pH 4.6.

Phytohemagglutinin skin test: diagnostic value for showing immunodeficiency in patients with cancer

The skin response to 5 mug of purified phytohemagglutinin (PHA) was studied in 299 subjects, including 58 normal controls, 92 patients without malignancies, and 149 patients with nonlymphomatous cancer. Other immunological responses, such as in vitro lymphocyte stimulation (62 subjects) and skin response to purified protein derivatives (PPD) (95 subjects), were tested simultaneously to examine their correlation with the PHA skin test. A positive reaction was observed 24 hr after intradermal injection of 5 mug of purified PHA in 56 (96.6%) of 58 normal controls, 40 (49.4%) of 81 untreated patients with cancer, and 24 (35.3%) of 68 cancer patients receiving anticancer therapy. Among 32 patients with gastric cancer tested, impaired skin reactivity to purified PHA was noted in patients in stage III or IV. A correlation was found between in vivo and in vitro responses to PHA in 46 (74.2%) of 62 individuals (P less than 0.001). The PHA skin test was repeated 4 times over a period of three months in patients without malignancies, and no significant change in tehir skin reactivity was detected. In repeated tests, the skin reactivity to purified PHA of patients with lung cancer varied depending on the clinical status, and the extent and type of anticancer therapy the patients were receiving. It is concluded that the PHA skin test is a simple diagnostic method for screening for immunodeficiency in cancer patients before and during the course of anticancer therapy. Other advantages of this test are that no presensitization is required and that it can be used repeatedly.

Clinical studies on diabetes mellitus and diseases of the oral region

Of the 25,672 patients who visited this clinic between January 1964 and March 1973, 126 were diabetic. These were examined statistically and the following results were obtained. 1. Together with diabetes the following disorders pertaining to the realm of oral surgery were observed: Alveolar pyorrhea (49 cases), infection of oral tissues other than periodontal tissues (24 cases), simple periodontitis (15 cases), tumors (13 cases), dental caries (9 cases), neuralgia (6 cases) and several disorders. 2. Of these 126 cases, 85 needed tooth extraction, which was actually performed in 67 cases with the following results: (a) Of the 67 cases, 13 developed complications such as dry socket, postoperative infection, sequestrum around the extraction socket, etc. This was a significantly higher incidence than in an equal number of controls. (b) In the cases with complications convalescence was prolonged to an average of 54.2 days. (c) In the cases with complications, the preoperative fasting blood sugar level averaged 194.5 mg/dl, which was much higher than in the cases which did not develop complications (average 142.4 mg/dl).