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The formation of the swim-bladder gases of some sea and fresh water fishes were investigated and the results may be summarized as follows : 1. As a rule, oxygen content in the swim-bladder is higher in a fish living at greater depth than at shallow, and sea water fishes, than fresh water ones. 2. Oxygen content in the swim-bladder of the fish living at great depth decreases after 1-2 days stay in the aquarium. 3. Carbon dioxide content in the swim-bladder of all fishes examined is very small. 4. Through the poisoning of carbon monoxide, the swim-bladder gas decreases in its oxygen content and increases slightly in its carbon dioxide. 5. Corresponding to the artificial increase or decrease of the external pressures influencing the body surface of the fish, oxygen content of the swim-bladder gases increases or decreases respectively. 6. After the evacuation of the swim-bladder gases, newly formed gases always contain high oxygen percentage. 7. When oxygen or carbon dioxide of high concentration are injected in the swim-bladder, these gases diffuse out easily through the wall of the swim-bladder during 1-2 days. 8. Oxygen dissociation curve of carp blood is remarkably steep compared with the human blood, and influenced very much with the presence of carbon dioxide so as to decrease the affinity of the blood to oxygen. 9. Histological examination of the swim-bladder of Sebastiscus marmoratus and Carassius auratus indicate characteristic structure of the blood capillaries which distributed in the internal layer of membranes and sinus-like dilated. 10. From the above experimental results, some considerations on the gas formation in the swim-bladder were offered.

The release of indomethacin from fatty-base suppositories, which had been stored at a low (4 degrees C) and a high (25-30 degrees C) temperature for about one month, was examined in vitro and in vivo. In the in vivo experiments, the plasma indomethacin levels after administration of suppositories stored at different temperatures were measured in conscious and anesthetized rats. In the in vitro release test using a dialysis cell method, much lower amounts of indomethacin were released from the suppositories stored at a high temperature than from those stored at a low temperature. The melting point of suppositories stored at a high temperature was higher by approximately 2 degrees C than those stored at a low temperature. In conscious rats, the plasma indomethacin levels attained after the intrarectal administration of suppositories stored at a high temperature were slightly lower than those after the animals were given suppositories stored at a low temperature, but the difference was significant only 30 min after administration. In anesthetized rats, the plasma indomethacin levels were markedly lower than those in conscious rats, and the influence of the storage temperature on the plasma indomethacin levels was clearly observed. These results suggest that in conscious rats many factors such as a locomotor hyperactivity and enhancement of gastrointestinal motility caused by the rectal administration mask the real character of suppositories. The in vitro and in vivo results show that the release of indomethacin from fatty-base suppositories stored at a high temperature is less than the release from those stored at a low temperature.

We constructed a plasmid, pBH103-ME5, in which the region encoding the 10 preS2 amino acid residues and the S domain of the hepatitis B surface antigen (HBsAg) were regulated by the promoter of the yeast repressible acid phosphatase gene. Saccharomyces cerevisiae carrying pBH103-ME5 produced the HBs antigen (yHBsAg), when it was cultured in a medium containing a low concentration of phosphate. The antigen was purified to homogeneity. Its molecular weight was determined by Western blotting to be 24,000, and its amino acid composition agreed well with that deduced from the nucleotide sequence. The C-terminal amino acid sequence of yHBsAg was exactly the same as that predicted from the nucleotide sequence, while the N-terminal amino acid acetylserine, which was followed by 8 amino acid residues coded by the preS2 region. These results indicate that the recombinant yeast produced a single polypeptide consisting of the preS2 region and the subsequent S domain after being processed at the N-terminus

Antroduodenal contractions were studied in rat preparations. Augmented duodenal contractions occurred spontaneously in coordination with antral contractions in normal and saline-pretreated preparations. The coordination did not occur when muscle layers and the myenteric plexus were transversely cut at the duodenum just anal to the gastroduodenal junction. In silent preparations, the coordinated contractions were produced by neostigmine or domperidone. When the antroduodenal junctional zone was pretreated with benzalkonium chloride, the augmented duodenal contractions did not occur spontaneously, and even after administration of neostigmine and domperidone although antral contractions occurred spontaneously. In these preparations, there were notably few myenteric neurons in the junctional zone, but the neurons were distributed normally in the areas where motility was recorded. The results suggest that myenteric neurons mediate antroduodenal coordinated contractions and that the coordination is modified by myenteric cholinergic excitatory and dopaminergic inhibitory pathways.

In order to elucidate the mechanism of latent infection of herpes simplex virus (HSV), reactivatable latency of three avirulent strains (SKO-1B, -GCr Miyama, SKa) of HSV type 1 was comparatively examined in a mouse latency model. The SKO-1B strain showed high rate of virus reactivation from explanted trigeminal ganglia without n-butyrate enhancement, while the other two strains showed a very low rate of virus reactivation in the absence of n-butyrate. In the presence of n-butyrate, however, the rate of the -GCr Miyama strain jumped to a comparable level with that of SKO-1B, although the rate of SKa remained at a low level. A more precise follow-up experiment changing the virus dose highlighted the difference of the ability to reactivate from the latent state between SKO-1B and -GCr Miyama. Virus titer in trigeminal ganglia during acute phase, infectivity to cell lines of neural origin, and susceptibility to acyclovir and phosphonoacetate were assayed to know the reasons for the variation in the ability of reactivatable latency among these strains. It was concluded that the reduced infectivity to neural cells, and limited ability of reactivatable latency shown by the SKa strain could mainly be attributed to the deficiency of thymidine kinase activity.</P>

Determination was made of step length, stride width, time factors and deviation in the center of pressure during up- and downslope walking in 17 healthy men between the ages of 19 and 34 using a force plate. Slope inclinations were set at 3, 6, 9 and 12 degrees. At 12 degrees, walking speed, the product of step length and cadence, decreased significantly (p less than 0.01) in both up- and downslope walking. The most conspicuous phenomenon in upslope walking was in cadence. The steeper the slope, the smaller was the cadence. The most conspicuous phenomenon in downslope walking was in step length. The steeper the slope, the shorter was the step length.

The cardioprotective effect of calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W-7) was examined on the isolated rat heart exposed to hypothermic and ischemic conditions by measuring distribution of lysosomal enzymes in myocardial cells, and leakage of creatine kinase (CK) during reperfusion and postischemic recovery in myocardial systolic function. Experimental hearts were infused with 20 degrees C Krebs-Henseleit bicarbonate buffer (KHB) or KHB containing TFP or W-7 for 2min every 30min during hypothermic ischemia. After ischemia for 120min at 20 degrees C, rat hearts were reperfused at 37 degrees C for 30min. TFP and W-7 improved functional recovery and prevented CK release. In TFP treated hearts, leakage of lysosomal enzymes was reduced significantly, whereas stabilization of lysosomes by W-7 did not occur. These results suggest that calcium-calmodulin dependent enzymes may play an important role in the development of cellular damage of the myocardium during hypothermic ischemia, although levels of leakage of lysosomal enzymes may be unreliable predictors of functional recovery after hypothermic ischemia.</P>

The role of alpha-1 adrenergic mechanism in the shaking stress-induced adrenocorticotropic hormone (ACTH), and plasma noradrenaline secretion and pressor response were investigated using conscious rats. We also studied whether or not central corticotropin releasing hormone (CRH) is involved in the shaking stress-induced ACTH secretion. The shaking stress caused significant elevations of plasma ACTH, noradrenaline, and systolic blood pressure. Intra-third ventricular administration of alpha-1 adrenergic blocker, bunazosin, inhibited the shaking stress-induced ACTH secretion, but did not alter stress-induced noradrenaline secretion and pressor response. Furthermore, intra-third ventricular administration of CRH antagonist, alpha-helical CRH, significantly attenuated stress-induced ACTH secretion. These results indicate that alpha-1 adrenergic pathway and CRH at least partly mediate the shaking stress-induced ACTH secretion.</P>

Previously, we pointed out the importance of the kynurenine metabolism in fetuses and neonates. We examined localization and developmental change of indoleamine 2,3-dioxygenase activity in human placenta. The indoleamine 2,3-dioxygenase was found localized in syncytiotrophoblast in the placenta. The indoleamine 2,3-dioxygenase activity was not detected in placenta in the early stage of gestation. It was first detected at around 14 weeks of gestation, increased rapidly thereafter and was maintained at high levels till near term. The indoleamine 2,3-dioxygenase activity was significantly lower in placenta with retarded intrauterine development. These results suggest the importance of placental indoleamine 2,3-dioxygenase during fetal development.</P>

<P>Peripheral T-cell lymphoma (PTL) is a distinctive clinical entity, albeit it comprises several diseases with histologically heterogeneous diagnoses. We studied prognostic factors on 30 patients diagnosed and treated at Shikoku Cancer Center Hospital. Clinical findings and laboratory data were evaluated by statistical analysis to investigate the important factors influencing survival duration. Variables influencing survival were stage, leukemic change, bone marrow infiltration (BMI), anti-human T-lymphocyte virus-type I antibody, white blood cell count, and lactate dehydrogenase (LDH). Multivariate analysis revealed high level of LDH and positive BMI as the important factors for short survival. Histological classifications of the Working Formulation and the T-lymphoma classification by Suchi et al. were also evaluated whether these were related with prognosis. Our data revealed that there was no significant relationship between histological subtype and survival duration. The study of prognostic factors provides valuable aids for us to understand the clinical characteristics of PTL patients with various backgrounds.

Some mechanisms to reduce methemoglobin (metHb) formation for the maintenance of normal oxygen transport have been proposed. To study the role of catalase (EC 1.11.1.6), metHb formation in the hemolysate of normal and Japanese acatalasemic human subjects were examined spectrophotometrically. Significantly increased level of metHb was induced by potassium ferrocyanide in the hemolysate of acatalasemic subject. The addition of catalase reduced the metHb formation, while 3-amino-1,2,4-triazole (AT), a specific inhibitor of catalase-H2O2 compound I, increased it. These results obtained from human subjects were well consistent with those from mice and suggested that catalase plays a role in protecting erythrocytes against metHb formation.

We investigated the antitumor activities of 5-fluorouracil (5-FU), 5'-deoxy-5-fluorouridine (5'-DFUR), 1-hexylcarbamoyl-5-fluorouracil (HCFU) and 1-(tetrahydro-2-furanyl)-5-fluorouracil (FT-207) in combination with hyperthermia in vitro. The antitumor effect of 5-FU (10(-4) M) was slightly enhanced by combination with hyperthermia (42 degrees C) for 2h, and the effect was determined to be additive. Synergistic enhancement of antitumor activity was obtained by the concurrent use of hyperthermia (42 degrees C, 2h) and 5'-DFUR (10(-4) M) or HCFU (10(-5) M). However, the antitumor effect of FT-207 (10(-4) M) in combination with hyperthermia was comparable that of hyperthermia alone. The synergistic enhancement of antitumor activity was not obtained for all drugs when the cells were preheated at 42 degrees C for 2h. On the other hand, when cells were pretreated with drugs before heat exposure, weak interactions were obtained after 5-FU and 5'-DFUR treatment, and a synergistic interaction was obtained after HCFU treatment. It is speculated that the metabolites of 5'-DFUR and HCFU enhance the cytotoxicity of 5-FU, or might change the threshold concentration for a cytotoxic effect of 5-FU in cancer cells.

A centrifugal pump was successfully used as a left ventricular assist device (LVAD) in a 54-year-old female who developed cardiogenic shock following open heart surgery. Cardiac index prior to the LVAD support was 1.4 l/min/m2 and increased to 3.0 l/min/m2 at removal of the device, which assisted for 88h. She resumed her daily activity 10 months after the operation and is in New York Heart Association functional class I.

Effects of Gabexate mesilate (GM) (([ethyl-4-(6-guanidino hexanoyloxy) benzoate] methane sulfonate)), a protease inhibitor, on the activities of catalase in liver, erythrocytes and reticulocytes from acatalasemic mice were examined. Preincubation without GM at 37 degrees C for 160 min lowered the catalase activities of liver, erythrocytes and reticulocytes from acatalasemic mice, to 24%, 40% and 10% of the initial levels, respectively. But, preincubation with GM at 37 degrees C for 160 min delayed the rapid decrease in activities of residual catalases in the liver, erythrocytes and reticulocytes of acatalasemic mice to 65%, 93% and 85% of the initial values, respectively. At 20 degrees C or below, no reduction in catalase activity of reticulocytes from acatalasemic mice occurred with or even without GM. At pH 5.0, the decrease in catalase activity of acatalasemic mice was small both in the presence and the absence of GM. In the alkaline range, the reduction in the enzyme activity of the mutant mice without GM was enhanced with increase in pH values up to 8.5. But the presence of GM during preincubation at pH 7.5, retained the catalase activity of acatalasemic mice, to 64% of the activity at pH 6.5. These data suggest that some factors affected by GM, might be responsible for the low stability and activity of catalase in the acatalasemic mice.

L-Dopa and three catecholamines in the amniotic fluid before and after labor were measured to confirm the amniotic fluid catecholamine levels at the end of gestation. L-Dopa values were higher than those of three catecholamines, and dopamine which was the predominant catecholamine, rose significantly after the onset of labor. Then, to evaluate the effects of L-dopa or dopamine on prostaglandin synthesis, strips of human decidua vera obtained from fetal membranes at the time of elective cesarean sections before the onset of labor were incubated in Krebs-Ringer buffer in the presence of L-dopa or dopamine. When L-dopa was added, the net production of prostaglandin(PG)F was significantly greater than that of the control at each incubation time. On the other hand, the significant rise was observed only after 10 min of incubation for PGE2 production. Dopamine had a stimulatory effect on PGF synthesis only after 15 and 30 min of incubation, and it also stimulated the release of PGE2 at each incubation time. These results suggest that dopamine and L-dopa in amniotic fluid stimulate the production of prostaglandin by the decidua in humans.

The left ventricular studies by Doppler echocardiography were performed in 50 patients with a Bjork-Shiley (B-S) mitral valve and 50 patients after implantation of a St. Jude Medical (SJM) mitral valve; the effect of valve replacement on the hemodynamic performance at rest and during bicycle exercise was determined from serial echocardiographic data. Twenty-eight patients (56%) of the B-S group and 42 patients (84%) of the SJM group showed a good response to the exercise. There was no significant difference in the effective orifice area at rest among each sizes of the B-S valve. In the SJM valve, on the contrary, the effective valve orifice area increases in parallel to the size of the SJM valve. There was a clear relation between the valve size and pressure gradient. The pressure gradient directly depends on the valve size and the effective orifice area in the SJM valve. High pressure gradient group in both prostheses had a tendency to take negative values of percent increase in stroke volume. Further, there were no cases showing positive values of percent increase in end-diastolic volume among the patients whose pressure gradients were assumed to be more than 10 mmHg at rest. It is suggested that impairment of inflow caused by the artificial valve, prosthetic valve stenosis, is possibly a significant factor causing left ventricular dysfunction, notably a decrease in stroke volume during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

DNA repair synthesis induced in permeable mouse ascites sarcoma cells by peplomycin, an antitumor antibiotic, was studied. Mouse ascites sarcoma (SR-C3H/He) cells were permeabilized with a low concentration of Triton X-100 in an isotonic condition. Permeable cells were treated with an appropriate concentration of peplomycin to introduce single-strand breaks in permeable cell DNA. DNA repair synthesis in peplomycin-treated permeable cells was measured by incubating the cells with four deoxynucleoside triphosphates in an appropriate buffer system. The DNA repair synthesis was enhanced by ATP and NaCl at near physiological concentrations. More than 90% of DNA synthesis in the present system depended on the peplomycin-treatment. The repair nature of the DNA synthesis was confirmed by a BrdUMP density shift technique. The repair patches were largely completed and ligated in the presence of ATP. Analyses using selective inhibitors for DNA polymerases showed that both DNA polymerase Beta and aphidicolin-sensitive DNA polymerases (DNA polymerase alpha and/or delta) were involved in the repair DNA synthesis.</P>

Polyester-crystic cast was observed to reach the peritubular capillary plexus following injection in sheep kidneys. Microvascular structures in this region are also reported in this study. Glomeruli were found to vary in size and shape. Diameters of afferent arterioles were larger than those of efferent arterioles. The glomerulus is supplied by more than one afferent arteriole, and in some regions, the blood in afferent arterioles joins collateral circulation via the intercapillary plexus. Morphological properties at the end of the peritubular capillary plexus were found to be remarkably significant.</P>

A 46-year-old woman with acromegaly and hyperthyroidism due to a pituitary adenoma. She had high serum thyroid-stimulating hormone (TSH) levels and very high serum growth hormone (GH) levels. Transsphenoidal removal of the tumor, post-operative irradiation, frontal craniotomy for removal of residual tumor and large-dose bromocriptine therapy were carried out consecutively. After therapy, serum GH levels gradually decreased, but not to the normal range, and serum TSH levels remained at inappropriately normal levels. Using immunoperoxidase techniques, GH-, TSH- and follicle-stimulating hormone (FSH)-containing cells were demonstrated in the adenoma. A long-acting somatostatin analogue (SMS 201-995, 600 micrograms/day) suppressed the serum GH level to the normal range with a concomitant suppression of TSH. Furthermore, the paradoxical serum GH responses to TRH and LH-RH were slightly improved. No important subjective side-effects were noted. Therefore, SMS 201-995 appeared to be a very effective drug in this patient with a GH- and TSH-producing pituitary tumor.</P>