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In order to elucidate the specific thyrotropic area in the hypothalamus, thyrotropin releasing hormone (TRH) content and concentration were measured in discrete hypothalamic nuclei and areas after triiodothyronine (T3) administration (T3 10 micrograms/rat/day for 6 days), thyroidectomy (TX) and acute cold exposure in male rats. In th TX and T3 groups, serum TSH levels were significantly increased in TX group and markedly decreased in T3 and TX with T3 groups as compared to the sham operated control group (Sham). TX produced a slight but nonsignificant decrease in TRH content in most of the hypothalamic nuclei examined as compared with the Sham group. However, a significant increase in TRH contents was seen in the anterior hypothalamic nucleus (AHN), median eminence (ME) and posterior pituitary (PP) in TX with T3 group as compared to the rats with only TX. In the acute cold stress experiments, serum TSH levels were elevated from 15 to 30 min of 4 degrees C exposure. Together with these peripheral changes, TRH content and concentration in the suprachiasmatic nucleus (SC) were increased significantly at 15 min and had returned to the normal level by 30 min after 4 degrees C cold exposure. However, in the paraventricular nucleus (PV) and dorsal premammillary nucleus (PMD), marked decrease in TRH concentrations were observed with this stress. Therefore, 1) decreased TSH release in TX rats treated with T3 was induced by the block of TRH release from the AHN and ME as compared with the TX group, and 2) elevated serum TSH levels in 4 degrees C cold stress might be induced by the release of TRH from the PMD and PV. These experiments demonstrate that the specific hypothalamic area for TSH release was located in some of the anterior and posterior hypothalamic nuclei and in the ME.

The effect of cytochalasin B (CB) on the surface structure of Ehrlich ascites tumor cells was investigated using the scanning electron microscope. The effect occurs in two steps: formation of zeiotic knobs on the cell surface and subsequent grouping of the knobs at one pole of the cell. The early step of zeiotic knob formation occurs at low concentrations of CB (0.5-1 microgram/ml) at 37 degrees C and at high concentrations of the drug (5-10 microgram/ml) at low temperature but within 1 min at 37 degrees C. This step is only partially inhibited by 5 x 10(-3) M sodium azide. The subsequent grouping of zeiotic knobs lasts for more than 2 min at 37 degrees C and occurs only in the case of high concentrations of CB. It is inhibited by sodium azide and is often associated with grouping of the microvilli, which are then lost from all of the cell surface except the area of knob-grouping.

125I-labeled insulin binding to peripheral human erythrocytes was studied in patients with chronic liver disease. The maximum specific 125I-labeled insulin binding was 12.10 +/- 1.13 %/4 x 10(9) cells (mean +/- SD, n = 10) in normal subjects, and significantly higher in cirrhotic patients (15.32 +/- 1.73 %, n = 11, P less than 0.01) but not in patients with acute and chronic hepatitis (11.44 +/- 2.10 %, n = 3 and 13.2 +/- 1.87 %, n = 7 respectively). The complication of diabetes mellitus significantly increased (P less than 0.05) the maximum insulin binding in chronic hepatitis. Scatchard analysis and average affinity analysis of the binding data suggest that increased insulin binding in cirrhotic patients is due to an increase in the number of insulin binding sites per erythrocytes. The complication of diabetes in chronic liver diseases results in an increase in affinity of insulin binding sites.

3-(3-methyl-3-butenyl)-1,2,3,4,5,6-hexahydro-6, 11-dimethyl-8-hydroxy-2,6-methano-3-benzazocine (KF-1820) is a derivative of benzomorphan and is different from pentazocine only in the site of the double bond. KF-1820 showed potent analgesic activity in all tests performed. KF-1820 was 6 to 12 times and 30 to 40 times more potent than morphine and pentazocine, respectively, when administered subcutaneously. KF-1820 had little or no narcotic antagonist property. Physical dependence liability tests indicated that KF-1820 may be a little less, or as liable as, pentazocine to produce physical dependence. ID50 values of KF-1820, pentazocine and morphine for depression of contractions of isolated guinea pig ileum to coaxial stimulation correlated well with their analgesic activities in the rodent. The dissociation equilibrium constant of KP-1820 confirmed the in vivo finding that KF-1820 had little or no narcotic antagonist property.

Generation of superoxide and hydrogen peroxide during interaction of nitrite with human hemoglobin was detected by chemiluminescence of luminol. Luminol chemiluminescence was inhibited by the addition of superoxide dismutase (SOD) and catalase. Methemoglobin formation induced by nitrite was also inhibited by the addition of SOD and catalase. The mechanism of methemoglobin formation by nitrite was discussed in regard to the oxidation of hemoglobin by superoxide and hydrogen peroxide as generated by the interaction of nitrite with hemoglobin.

Computer processed adrenal imaging using dual-radioisotopes, 6 beta-iodomethyl-19-nor-cholest-5(10)-en-3 beta-ol-131I and 99mTc-phytate was performed in 12 patients with primary aldosteronism and 4 with Cushing's syndrome due to adrenocortical tumor. Adreno-photoscanning and hepato-photoscanning were performed in the same position 2-4 days following intravenous administration of radiocholesterol. The scintigraphic information was stored on cassettes and scan subtraction and a digital-computer method for data smoothing were performed on an oscilloscope. The tumor site could be determined in all cases until day 4 by this computer processed image.

The distribution of 2,4-dinitrophenyl (DNP) groups in the draining lymph nodes of guinea pigs 12 h after painting the skin with 2,4-dinitrochlorobenzene (DNCB) was examined by a peroxidase labelled antibody method using antibody against DNP groups. DNP groups were detected on cells that were found mainly in the subcapsular sinus of the lymph nodes. Electron microscopic examination showed DNP groups distributed on the surface of lymphocytes. The significance of these findings is discussed.

Arginine vasopressin (AVP) was released in vitro in a pulsatile pattern from the hypothalamo-neurohypophyseal system (HNS) and from the hypothalamus during continuous hyperosmotic stimuli with NaCl or fructose. No significant difference was found in the AVP pulse frequency between the two kinds of hyperosmotic agents. AVP was released from the HNS in a dose-related manner under NaCl stimulation. When the neural lobe was stimulated with NaCl or fructose, a clear AVP pulse pattern was not apparent. Urea failed to evoke a significant AVP release from the neural lobe or HNS. A stepwise increase in NaCl stimulation from 5 to 25 mEq induced a AVP response from the HNS and hypothalamus similar to that under constant stimulation at 25 mEq NaCl. This phenomenon was also found with fructose or sucrose. These results suggest that AVP release from the HNS during continuous osmotic stimulation has a pulsatile pattern regardless of the hyperosmotic substance or osmotic pressure. This AVP release accurately reflects the physiological function of the hypothalamus without modulation in the neural lobe. These results also suggest that the total amount of AVP was related to the osmotic pressure or the osmotic substance but that the frequency of the pulse release was not, moreover, that the AVP release depends not only on the absolute osmotic pressure, but also on the changing rate of osmotic pressure.

In rats anesthetized with urethane, the effects of distention of the stomach upon cecal motility and neural mechanisms which generate this effect were studied. Cecal motility was inhibited which generate this effect were studied. Cecal motility was inhibited when the pars glandularis of the stomach was distended by pressure ranging from 25 to 30 cm H2O. This inhibitory reflex was not affected by bilateral cervical vagotomy, but completely abolished following bilateral severance of the greater splanchnic nerves or after intravenous administration of guanethidine. After transection of the spinal cord at the level of the 5th thoracic segment the inhibitory reflex remained intact, but was abolished following pithing of the 6th thoracic segment and below. It may be concluded that the afferent and efferent path of the gastrocecal inhibitory reflex mainly pass through the greater splanchnic nerves and the reflex center is located in thoracic segments caudal to the 6th thoracic segment.

The integrated proviral DNA of avian sarcoma virus (ASV) in host cell chromosomes has been isolated and stored in saline sodium citrate (SSC) solution or in 70% ethanol at 4 degrees C in a refrigerator over 4 years. This DNA was assayed by transfection of chick embryo cells(CEC). The biological activity of cellular transformation by the stored DNA was compared with that of a fresh isolate of the proviral DNA. The efficiency of the transfection by each DNA was almost the same.

Drug effects were studied on anaphylactic histamine release from rat mast cells sensitized in vitro with mouse IgE antibody. When histamine release was elicited by adding Ca-++ at various times after antigen-stimulation of sensitized cells in Ca++-free medium, the drugs to be tested were added shortly before each Ca++ addition. Quercetin was effective only when added before or immediately after antigen. Theophylline and disodium cromoglycate (DSCG) were active irrespective of the time interval between antigen and Ca++ addition. Verapamil was more effective when added before or simultaneously with antigen than when added later. When tested in the two-stage experiments, quercetin showed inhibition only in Stage 1 and verapamil was inhibitive primarily in Stage 1, while theophylline and DSCG wee only inhibitive in Stage 2. It seems that quercetin selectively and verapamil primarily act to block calcium-gate opening resulting from antigen-antibody interaction on the mast cell membrane, while theophylline and DSCG selectively inhibit the passage of calcium through open calcium channels.

<p>A cytogenetic study was performed on 74 children with at least three major or minor congenital malformations and mental retardation, and whose phenotypes did not fit any well-defined syndrome. The chromosomes were examined routinely using banding techniques. A total of 11 patients (14.9%) was found to have a major chromosome abnormality: one patient had a sex chromosome structural abnormality and 10 patients had an autosomal structural abnormality, including 4 patients with partial trisomies, 4 patients with partial monosomies, and 2 patients with tertiary trisomies. Two of them had probable intrachromosomal duplication which would not have been identified by conventional staining alone. Familial transmission was ascertained in 5 of 10 cases in which both parents were studied. In addition, 5 patients (6.8%) were noted to have the following chromosome heteromorphisms: partial inv 1qh, inv 9qh, 9qh+, and Yqh+. These results show that chromosome abnormalities contribute much to the etiology of unclassifiable multiple malformations associated with mental retardation. Furthermore, the demonstration of subtle chromosome rearrangements by means of banding techniques provides important implications in medical practice for the diagnosis of affected patients as well as for the genetic counseling of the families.</p>

The antimycotic action of 1, 4-bis-(m, m'-amidinophenoxymethyl)-cyclohexane dilactate (MAC), a synthetic diamidine compound, on Candida albicans was studied. The minimum inhibitory concentration (MIC) ranged from 3.31 to 6.25 micrograms/ml against both standard and clinically isolated strains. MAC was fungistatic at MIC and weakly fungicidal at the concentration of 100 micrograms/ml. MAC did not affect the cell wall or cause cell lysis. Intracellular constituents, such as 260 nm and 280 nm absorbing materials, were released from the cells by treatment with MAC indicating that MAC affected membrane permeability. The release of 260 nm absorbing material was inhibited by the presence of Ca2+ and Mg2+. Acidic phospholipids such as cardiolipin and phosphatidylglycerol inhibited the anti-Candida activity of MAC, but sterols and lecithin were not inhibitory, indicating that MAC interacted with acidic phospholipids of the cell membrane. Freeze-fracture electron microscopy showed that MAC caused aggregation of membrane particles and patch formation on the P face, which may indicate that MAC is a membrane disrupting agent. It appeared that MAC affected C. albicans at the cell membrane by interacting with acidic phospholipids and caused disorganization of the membrane structure resulting in the release of intracellular constituents without lysis.

Simian virus 40 (SV40) DNA was microinjected into cultured mammalian cells by means of electrophoresis (iontophoresis). Successful transfer of DNA into cells was confirmed by detecting SV40 T antigen using the indirect immunofluorescent technique.

To investigate cellular interactions between human T and B lymphocytes in various diseases, we established a technique to prove terminal differentiation of B lymphocytes into immunoglobulin synthesizing and secreting cells. We also established a double antibody radioimmunoassay to measure the amount of IgG, IgA and IgM synthesized and secreted in culture supernatants. Purified immunoglobulins were obtained from sera of patients with myeloma or macroglobulinemia. The peripheral blood lymphocytes from 25 normal individuals had the geometric mean synthetic rates of 1886 ng for IgG, 1607 ng for IgA and 1173 ng for IgM per 1 X 10(6) cells when cultured for nine days in the presence of pokeweed mitogen. The method is simple and sensitive, and is thought to be useful for examining human lymphocyte function in vitro.

Masugi nephritis was induced in rats by a single intravenous injection of rabbit anti-rat kidney serum, and studied with a scanning electron microscope. A characteristic finding was the presence of white cells, probably polymorphonuclear leukocytes, with many microspikes which penetrated through degenerated glomerular endothelial cells to be in direct contact with the glomerular basement membrane. This finding confirms the pathogenic role of leukocytes in glomerulonephritis induced by anti-glomerular basement membrane antibody.

Thirty-seven consecutive cases of mitral valve replacement have been retrospectively reviewed. The prognostic significance of preoperative clinical, hemodynamic and quantitative angiographic factors for survival has been evaluated. In the Mitral stenosis (MS) group, all of the patients who showed small Stroke volume index (SVI) (less than 45 ml/m2) with pulmonary hypertension died from the low output syndrome. The prognosis was poor in patients who had large cardiothoracic ratio (CTR) in the MS group. Aortic valve replacement must be considered when moderate aortic regurgitation is associated with mitral valve disease. In the MR factors for predicting the survival. The eccentricity ratio is also a sensitive parameter for recognizing a patient who will have a poor prognosis after mitral valve replacement. The main mode of death was found to be heart failure due to myocardial impairment.

Insulin and human erythrocyte cell membrane interactions were studied with respect to binding and dissociation. The per cent of specific binding of 125I-labeled insulin to erythrocytes was directly proportional to the cell concentration. The optimum pH for binding was 8.1. The initial binding rate was directly proportional to, and the steady state insulin binding was reversely proportional to, the incubation temperature. The per cent of specific binding of 125I-labeled insulin was 12.10 +/- 1.13 per cent (mean +/- SD)/4 X 10(9) cells (n = 10) at 0.8 ng/ml insulin. Native insulin competed with 125I-labeled insulin for binding and showed almost complete inhibition at 10(4) ng/ml. The Scatchard plots were upward concave. Maximum binding capacity was 230 binding sites per cell. The average affinity constant decreased as the per cent of fractional occupancy increased. Affinity constants for the empty and filled sites were 1.49 and 0.16 X 10(8) M-1 respectively. Bound insulin was displaced by native insulin. The dissociation rate by "dilution + native insulin" was higher than that by "dilution only". The dissociation rate was accelerated even by the physiological concentration of insulin and maximum at 100 ng/ml. It is concluded that human erythrocytes have insulin binding sites which are indistinguishable from insulin receptors on the target tissues for insulin.

A permeable cell system has been developed by treatment with saponin for studying in vitro replication of DNA and chromatin. DNA replication of simian virus 40 nucleoprotein complexes (SV40 chromatin) in saponin-treated permeable cells was found to be more efficient than that in digitonin-treated permeable cells. Autoradiography of the agarose-gel revealed that [alpha-32P]dCTP was incorporated into SV40 DNA I, II and replicating intermediates. The time course of the incorporation indicated complete replication of SV40 DNA and chromatin with a full number of nucleosomes. The saponin-treated permeable cell system will serve as a useful system for studying in vitro replication of DNA and chromatin in eukaryotic cells.

Serum specimens from 12 patients with type A hepatitis were analyzed for immunoglobulin M-type antibody to hepatitis A virus (IgM anti-HA). A recently developed solid-phase radioimmunoassay kit for IgM anti-HA (HAVAB-M, Abbott Laboratories) and a competitive binding radioimmunoassay kit (HAVAB, Abbott Laboratories) with or without 2-mercaptoethanol treatment, as modified by Yano et al. (Acta Hepatol. Jpn. 21, 704-712, 1980) were used to obtain an M-index. All specimens obtained within 60 days of the onset of illness and specimens from 2 of 4 patients later than 60 days after the onset were positive with the HAVAB-M test. This test gave negative results to sera which were positive for anti-HA by a standard HAVAB test in the following: 3 patients with type B hepatitis; 5 with non-A, non-B hepatitis; 11 healthy adults; and 10 sera strongly positive for rheumatoid factor. The M-index for type A hepatitis in sera within 30 days of the onset (mean value of the M-index, m, = 1.52; standard deviation, SD, = 0.25) was significantly higher than that for non-A hepatitis (m = 1.05; SD = 0.15) and for healthy adults (m = 1.02; SD = 0.10). The simplicity and usefulness of the HAVAB-M test in diagnosis of acute type A hepatitis over those measuring the M-index by HAVAB tests were shown by direct comparison of the results.