Dimer formation in radiation-irradiated aqueous solution of lysozyme studied by light-scattering-intensity measurement

The reaction of lysozyme with OH., Br.-2 and e-aq, produced in an aqueous solution by pulsed electrons and gamma-rays, were investigated. Irradiated enzymes showed an increase in the light scattering intensity (LSI) which is proportional to the absorbed dose. Results obtained from SDS gel electrophoresis confirm dimerization of lysozyme, which is considered to be responsible for the increase in LSI. It was found that the rate constant of the dimerization of protein radicals produced in the reaction with OH. is 2K=(1.0 +/- 0.3) X 10(6)M-1 s-1 and the yield of the dimerization is 0.6 in G. The enzymatic activity of the dimer is shown to be reduced to about 30 per cent of that of the intact enzyme. It is concluded that the radiation-induced inactivation of lysozyme is largely due to dimerization.

The oxidation of ferrocytochrome c by Br2-, (SCN)2-, N3 and OH radicals studied by pulsed-electron and gamma-ray radiolysis

The reactions of ferrocytochrome c with Br2-, (SCN)2-, N3 and OH radicals were followed by measuring the change in the optical spectra of cytochrome c on gamma-irradiation as well as the rate of change of absorbance upon pulse irradiation. Ferrocytochrome c is oxidized to ferricytochrome c by Br2-, (SCN)2- or N3 radical with an efficiency of about 100% through a second-order process in which no intermediates were observed. The rate constants in neutral solutions at I = 0.073 are 9.7 . 10(8) M-1 . s-1, 7.9 . 10(8) M-1, 1.3 . 10(9) M-1 . s-1 for the oxidation by Br2-, (SCN)2- and N3 radicals, respectively. The rate constants do not vary appreciably in alkaline solutions (pH 8.9). The ionic strength dependence was observed for the rate constants of the oxidation by br2- and (SCN)2-. Those rate constants estimated on the assumption that the radicals react only with the amino acid residues with the characteristic steric correction factors were less than one-tenth of the observed ones. These results suggest that the partially exposed region of the heme is the probable site of electron transfer from ferrocytochrome c to the radical. Hydroxyl radicals also oxidize ferrocytochrome c with a high rate constant (k greater than 1 . 10(10) M-1 . s-1), but with a very small efficiency (5%).

Acute lead poisoning of the pigeon induced by single, intraperitoneal administration of lead acetate

A single dose of lead acetate (either 30 mg/kg or 150 mg/kg) was intraperitoneally (i.p.) administered to adult feral pigeons, Columba livia var and the effects of calcium disodium ethylenediamine tetraacetate (CaNa2EDTA), (0, 150, 300, 600 mg/kg), administered i.p. twice a week in the ensuing period were observed. Lead acetate caused dose related mortality and decreases in weight, hematocrit and delta-aminolevulinic acid dehydratase activity (ALA-D). Acute toxicity of lead acetate in the pigeon, when given intraperitoneally, appeared approximately equivalent to that in the rat and mouse in terms of LD50. Blood lead (blood Pb) levels observed during the lethal stage were five to ten times less than those reported for chronic oral lead poisoning in the pigeon. Biological implications of elevated levels of blood Pb observed in the feral pigeon in the urban Tokyo area are discussed. CaNa2EDTA induced dose related recovery in ALA-D in 30 mg/kg group, and reduction of blood Pb levels in the group dosed with 150 mg/kg of lead acetate.

Fibrinolytic activity during pregnancy

It has been a general concept that fibrinolytic activity is diminished during pregnancy. However, increase in FDP (fibrin/fibrinogen degradation products by plasmin digestion) which indicates accelerated fibrinolytic activity is also observed during pregnancy. To clarify these conflicting findings, alpha-2-plasmin inhibitor and FDP, sensitive indicators of fibrinolytic activity, were studied during pregnancy. Decrease in plasmin inhibitor and increase in FDP were found during pregnancy suggesting that fibrinolytic activity is accelerated during pregnancy. Since FDP level was higher in blood samples from the uterine vein than those from the artery, the accelerated fibrinolysis characterized by decrease in plasmin inhibitor and increased FDP, might be reflection of local event. On the other hand, systemic blood remains still hypofibrinolytic in normal pregnant condition.

[Correlation between the thalamus EEG and rCBF in the thalamus infarction in the dogs (author's transl)]

We have made an investigation of the correlation between the changes in thalamic EEG and rCBF immediately following occlusion 4 arteries at the base of the brain using thalamic infarction model with 38 dogs. Changes in EEG patterns due to vascular occlusion were divided into 4 grades. A tendency was found for decreases in rCBF to be greater the more marked were the EEG changes. Animals showing mild EEG changes in which there was only slight attenuation of voltage had rCBF values roughly 63% those prior to occlusion; animals with moderate EEG changes in which there was voltage attenuation and an increase in slow wave components had rCBF values of 34%; and animals with severe EEG changes in which there was voltage attenuation and complete disappearances of fast wave components showed rCBF values of roughly 29%.

Recirculation in the acute period of cerebral infarction: experimental research on brain swelling and its suppression by using mannitol or glycerol

Using our previously published "incomplete cerebral hemispheric infarction model in dogs" (produced by simultaneous ipsilateral occlusions of the anterior cerebral artery at the branching of the ethmoidal artery from its A1 portion, the A2 portion, the internal carotid artery, the posterior communication artery, the posterior cerebral artery, and the anterior cerebellar artery), two, four, or six hours occlusion of blood flow was undertaken. Observations were then made on the degree of brain swelling following recirculation due to administration of mannitol or glycerol solutions. Furthermore, the leakage of Evans blue was investigated to determine the damage to the blood brain barrier. 1. In the animals given mannitol or glycerol, brain swelling was suppressed, following two hours occlusion, In the animals given mannitol, however, brain swelling was not suppressed after four or six hours occlusion. 2. After two hours occlusion in the animals given mannitol, leakage of Evans blue was slight compared with the untreated group. In the six hours occlusion groups, severe leakage of Evans blue was seen in both the untreated animals and the mannitol-treated. After two hours occlusion, in some animals which had been given glycerol, severe leakage of Evans blue was seen, even when there was little brain swelling.

Suppression of pokeweed mitogen-induced differentiation of human B cells by in vitro levamisole-treated T lymphocytes

The generation of immunoglobulin-producing cells from human peripheral blood lymphocytes in pokeweed mitogen-simulated cultures was significantly suppressed by levamisole. Greatest suppression was observed when cells were incubated with levamisole at a concentration of 10(-6) M for 20 min or more prior to culture. Such suppression occurred when untreated as well as levamisole-treated B cells were co-cultured only with levamisole-treated T cells. Adding of levamisole-treated T cells to a combination of untreated autologous B and T cells resulted in the suppression of B cell differentiation. The results suggest that levamisole treatment of lymphocytes exerts suppression on pokeweed mitogen-induced B cell differentiation through its effect on T cell regulatory properties.

[Changes of tissue pH in dog brain during ischemia--alkaline shift (author's transl)]

Brain pH changes during ischemia were observed by the newly established histochemical technique in Dr. Kogure's laboratory (Miami). The technique utilizes intravascular injection of neutral red as a pH indicator. Its use is based on the fact that neutral red is red in acid and yellow in alkaline pH. Thalamic infarction model in dogs was used in this experiment. The methods of producing this model by temporary occlusions of brain arteries have been published elsewhere. The animals were anesthetized with sodium thiopental, immobilized with pancronium bromide, and artificially ventilated with room air. Blood gases and blood pH were adjusted to normal. Before the experimental procedure, 3 ml/kg of a 5% saline suspension of neutral red was injected slowly into the femoral artery. After occlusions of cerebral arteries, the brain was frozen in situ by pouring liquid nitrogen into the bottomless cup. The frozen brain was mounted on a cryostat at -20 degrees C and sliced coronally in 10 micron thickness. Color differences in the serial sliced brain surface were observed. No change in the color was observed in the sham operated brains. Thirty minutes following occlusion, the color of the thalamus is reddish, and it was estimated that this area became acidotic. 1 hour following occlusion, too, the thalamus is acidotic. But 2 hour following occlusion, the color of the thalamus became yellowish, indicative of alkaline shift. From this experimental results, it is considered that the pH of ischemic brain changes dynamically, that is, ischemic brain becomes acidotic in the early stage of ischemia but with the lapse of time alkaline shift occurs.

Induction of suppressor activity on B-cell differentiation in human T-cell subset without fc(IgG) receptors by levamisole administration

A single oral dose of 150 mg levamisole was administered to five healthy adults. Circulating Fc(IgG) receptor-bearing T cells (T gamma cells) increased for 5 days after levamisole intake, but total E rosette-forming cells showed no significant alterations. The generation of immunoglobulin-producing cells in the peripheral blood lymphocytes (PBL), which was induced in the in vitro pokeweed mitogen (PWM)-stimulated cultures, was significantly suppressed for 5 days after levamisole administration. Suppressor T-cell activity on B-cell differentiation, which was induced by levamisole intake, was evaluated by co-culturing with allogeneic untreated adult PBL in the PWM system in six other volunteers. A seemingly dose-dependent suppression on B-cell differentiation was exerted by T cells isolated on day 3 of levamisole treatment, but not by T cells differentiation was exerted by T cells isolated on day 3 of levamisole treatment, but not by T cells which were isolated before or on day 14 of the experiment. When T cells were fractionated into two subsets with regard to the presence or absence of Fc(IgG) receptors, suppressor T-cell activity appeared to be generated by levamisole largely in T cells lacking Fc(IgG) receptors, but not in T gamma cells.

Clinical features of 22 cases with "inter-sterno-costo-clavicular ossification". A new rheumatic syndrome

We present 22 cases with inter-sterno-costoclavicular ossification. Clinical and pathological findings show that abnormal ossification observed in this situation is due to non-suppurative chronic inflammation of the soft tissues around the sterno-costo-clavicular region such as the costo-clavicular ligament. We have classified X-ray findings into three stages according to the extent of the ossification; localized, generalized, and hyperostotic, and show that the disease progressed in this sequence. A considerable number of the patients showed abnormal X-ray findings in the spine or the sacro-iliac joint. Frequent association of pustulosis palmaris et plantaris was noted in this disease. Most of the cases were treated effectively with anti-inflammatory drugs, but a few cases required surgical resection of the ossified mass with the clavicle or the first rib in order to relieve the severe pain.

[Production of infarction model in dogs by several brain arteries occlusion. Part 1: Production of hemispheric non blood supply model (author's transl)]

Experimental brain infarction in model animals should most ideally be constant in the site of occurrence, be of severity that is controllable by the occlusion time of blood flow and, moreover, be reproducible at a high rate to desired extent and severity. However, among infarction models elaborated in animals so far, only thalamus infarction model in dogs which were reported by us previously have been proven to satisfy almost all of these requirements. In experiments with these model dogs we found that an extensive infarction can be produced at a high frequency in the involved hemisphere by a transient occlusion of blood flow at such intracranial levels as the internal carotid artery, the junction of the anterior cerebral artery and ophthalmic artery, the middle cerebral artery, the origin of the segment A2 of the anterior cerebral artery, and the junction of the posterior communicating artery and posterior cerebral artery. During about one hour following the releasing of the arteries approximately 2 hours occlusion, the development of severe brain edema resulted involving the whole hemisphere on the affected side invariably in all cases. This method for experimental production of brain infarction permits to control the degree of resultant brain edema by changing the duration of occlusion of blood flow, requires simple manipulations only and ensures production of a constant lesion. With these advantage it can be anticipated to prove of great benefit in the study of postischemic brain edema.

[The relationship between the rupturing of intracranial aneurysm and season, weather and patient's acitivity (author's transl)]

Some physical and mental stresses have been notices as the exciting factors for the occurrence of cerebrovascular diseases. However, little has been known about them of ruptured intracranial aneurysms. From this point of view, the correlation between the several physical strains and the occurrence of ruptured intracranial aneurysm were studied in this report. This study was based on 920 cases of ruptured intracranial saccular aneurysm which were verified by direct aneurysmal surgery. As for the season, the occurrence of ruptured intracranial aneurysms was apt to be frequent in winter and infrequent in summer. No relation between the onsets and the meteorological fronts could be found. The incidence during sleep was about 6%. This incidence was thought to be rather lower considering the fact that one-third of our lives is spent in sleep. Lifting and bending, defecation and/or urination and emotional strain were among the commonest environmental events associated with the onset. Based on these results, wheather or season, which is mild physical stress, can in no way be considered a great cause of rupturing of intracranial aneurysm, but it should seen that patient's activities or events have some influences in rupturing of aneurysm to a great extent.

The anterior and the posterior longitudinal ligaments of the lower cervical spine

The anterior and the posterior longitudinal ligaments (ALL and PLL) of the cervical spine were examined. The ALL and the deep layer of the PLL are continuous, and surround the vertebral body. The superficisl layer of the PLL surrounds the dura mater, nerve roots and the vertebral artery, suggesting that this membrane may serve as a protective membrane for the soft tissues inside the vertebral canal rather than as a conventional ligament.

The position of the superior articular process of the cervical spine. Its relationship to cervical spondylotic radiculopathy

Cervical spondylotic radiculopathy is likely to develop when the superior articular process is anterior to the posterior margin of the vertebral body, as determined by lateral radiographs of the spine.

Endoscopic retrograde cholangiopancreatography (ERCP) performed in children

The value of ERCP in children is demonstrated on 3 cases. By using a usual duodenofiberscope (JF-B2), in 2 cases under general anesthesia and in one case after premedication with 1 ml Buscopan i.m., a similar technique is used as in adults. In congenital choledochal cyst only ERCP allowed the exact judgement of the distal part of the common bile duct and its relation to the pancreatic duct. Therefore, an exact preoperative diagnosis can be established. When duodenofiberscope will be more improved ERCP will also be possible in the newborn infant. Than the differential diagnosis of congenital biliary atresia, other congenital failures in infants causing jaundice and hepatitis in infant will be established endoscopically.

Distribution of HLA-B27 in patients with juvenile rheumatoid arthritis

HLA antigens were examined in 27 patients with juvenile rheumatoid arthritis. HLA-B27 was found in none. The result was different from most other previously reported studies. The most likely explanation for this difference is the possibility that some patients with juvenile ankylosing spondylitis may have been included among the patients in the other studies.

Reactions of the ferri-ferrocytochrome-c system with superoxide/oxygen and CO2-/CO2 studied by fast pulse radiolysis

The reduction of ferricytochrome c by O2- and CO2- was studied in the pH range 6.6-9.2 and Arrhenius as well as Eyring parameters were derived from the rate constants and their temperature dependence. Ionic effects on the rate indicate that the redox process proceeds through a multiply-positively charged interaction site on cytochrome c. It is shown that the reaction with O2- (and correspondingly with O2 of ferrocytochrome c) is by a factor of approx. 10(3) slower than warranted by factors such as redox potential. Evidence is adduced to support the view that this slowness is connected with the role of water in the interaction between O2-/O2 and ferri-ferrocytochrome c in the positively charged interaction site on cytochrome c in which water molecules are specifically involved in maintaining the local structure of cytochrome c and participate in the process of electron equivalent transfer.

Method for estimating the decomposition of hexadecane in the marine environment

A method, based on quantitating 14CO2 produced from [14C]hexadecane, has been developed for estimating the rate of hexadecane decomposition in seawater of Tokyo Bay during the summer stagnation period. The rate of hexadecane decomposition was from 0.1 to 1.3 mug/h per liter of seawater at the surface layer in the polluted gyre of the inner part of Tokyo Bay during the summer of 1974. A similar horizontal distribution pattern was seen for the density of hexadecane-decomposing bacteria.