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Biomedical subjects

Y Abe

Publications and source records attributed to Y Abe.

At least 955 records · Page 53Linked to original sources
PubMed1986

Effects of ouabain on autoregulation of renal blood flow in dogs.

Effects of ouabain on the autoregulation of renal blood flow (RBF) and renin release were examined in filtering and nonfiltering kidneys of anesthetized dogs. Autoregulation of RBF was observed in both kidneys; however, autoregulation in the nonfiltering kidney was comparatively less efficient. These findings indicate that both the myogenic mechanism via a sensor element in the afferent arteriole, a so-called baroreceptor, and the tubuloglomerular feedback mechanism via the macula densa are essential for complete autoregulation. In both the control and nonfiltering kidney, intrarenal arterial infusion of ouabain abolished the autoregulation of RBF and glomerular filtration rate, with no change in the renal vascular sensitivity to vasoactive substances or in renin release induced by pressure reduction. Since various vasoactive drugs elicited a normal vascular response, it appears that the site of action of ouabain was not the vascular contractile elements; at least, an impairment of autoregulation during ouabain infusion was apparently not due to a defect in these elements. These results suggest the possible existence of another mediator, a sensor element in the afferent arteriole that is affected by ouabain. Ouabain may abolish the autoregulation of RBF and renin release via a modification of this baroreceptor in the afferent arteriole as well as through inhibition of the macula densa.

Animals↗
PubMed1986

Conjugate pendular nystagmus evoked by accommodative vergence.

Conjugate pendular nystagmus evoked by accommodative vergence in a healthy 18-year-old girl is described. This is clinically demonstrated to be induced by accommodative convergence, and not related to fusional convergence. The lack of neurological or ophthalmic abnormalities supports the classification of a 'congenital' type of this rare phenomenon. A differential diagnosis is also discussed.

Accommodation, Ocular↗
PubMed1986

Orbital tumor diagnosis by positron emission tomography using 18F-fluorodeoxyuridine.

The distribution of 18F-labeled 5-fluoro-2'-deoxyuridine (18F-FdUrd) in orbital tissue, tumor and aseptic inflammation was examined in rats. The distribution in paraorbital structures, other than bone, was low. The tumor-to-organ ratios were sufficient for tumor imaging by positron emission tomography (PET). Positron emission tomography with 18F-FdUrd clearly showed the experimental orbital VX-2 tumor in rabbits. The difference between the experimental orbital tumor and croton oil-induced aseptic inflammation or a normal orbit was apparently established in the PET image with slow and fast clearance of radioactivity, respectively.

Animals↗
PubMed1986

Role of the valence of concanavalin A in the activation of guinea pig polymorphonuclear leukocytes.

Stimulation of polymorphonuclear leukocytes (PMN) by tetravalent concanavalin A (alpha-ConA) induces membrane depolarization preceding the onset of superoxide anion (O2-) production. Both divalent and monovalent ConA analogues were studied to evaluate the role of valence. Monovalent ConA (m-ConA) was inactive in stimulating O2- production and divalent derivatives were less active than native alpha-ConA. Similarly, membrane depolarization was dependent on the valency of ConA. m-ConA did not induce a marked change in membrane potential, whereas sustained depolarization occurred with multivalent ConA. The formation of multiple linked interactions between surface receptors may be an important early event in the activation of PMN by ConA.

Animals↗
PubMed1986

Plasma thromboxane and prostacyclin: comparison during normal pregnancy and pregnancy complicated by hypertension.

Plasma levels of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), stable metabolites of two prostanoids with opposing biological effects, TXA2 and prostacyclin, were measured by radioimmunoassay in normal pregnancy (controls) and pregnancy complicated by hypertension (PIH) from 32 to 36 (Period 1; P1) and from 36 to 40 (Period 2; P2) weeks of gestation. The plasma concentration of each compound in the control subjects was 265.6 +/- 58.4 (TXB2), 132.4 +/- 16.5 (6-keto-PGF1 alpha) for P1 (n = 10) and 142.6 +/- 11.8 (TXB2), 68.5 +/- 5.2 (6-keto-PGF1 alpha) for P2 (n = 10) respectively (pg/ml, mean +/- s.e). In the patients with PIH, TXB2 concentrations increased moderately for P1 (419.2 +/- 21.2; n = 7) and significantly (p less than 0.005) for P2 (452.8 +/- 31.0; n = 7) respectively (pg/ml, mean +/- s.e), while the plasma levels of 6-keto-PGF1 alpha revealed a slight to moderate decrease both for P1 (84.5 +/- 4.0; n = 7) and P2 (59.7 +/- 8.1; n = 7) respectively (pg/ml, mean +/- s.e). The physiological balance of TXB2 to 6-keto-PGF1 alpha was significantly greater (p less than 0.005) in the patients with PIH, where the TXB2/6-keto-PGF1 alpha ratio was 5.2 +/- 0.7 for P1 and 9.4 +/- 2.3 for P2 respectively (mean +/- s.e) compared with that of the controls, where it was 2.4 +/- 0.4 for P1 and 2.0 +/- 0.2 for P2 respectively (mean +/- s.e).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Comparison of plasma prostanoid levels in the human cord artery in normal and fetal distressed deliveries.

Prostaglandin E2 (PGE2), thromboxane B2 (TXB2; as a stable metabolite of TXA2), prostaglandin F2 alpha (PGF2 alpha) and 6-keto-PGF1 alpha (as a stable end product of prostacyclin) have been measured by using specific radioimmunoassay in the plasma of the cord artery immediately after delivery before the cord was clamped. Plasma prostanoid concentrations in normal deliveries (n = 8, as controls) were 24.8 +/- 2.6 (PGE2), 246.8 +/- 37.0 (TXB2), 122.2 +/- 13.3 (PGF2 alpha) and 82.1 +/- 7.7 (6-keto-PGF1 alpha) respectively (pg/ml, mean +/- s.e). On the other hand, in fetal distressed deliveries showing continuous bradycardia (n = 6), they increased significantly to 275.4 +/- 20.1 (PGE2), 948.6 +/- 102.5 (TXB2), 218.0 +/- 21.4 (PGF2 alpha) and 1498.6 +/- 298.4 (6-keto-PGF1 alpha) respectively (pg/ml, mean +/- s.e, p less than 0.005). However, both PGF2 alpha/PGE2 and TXB2/6-keto-PGF1 alpha ratios declined significantly from 4.70 +/- 0.33 to 0.68 +/- 0.05 and from 3.07 +/- 0.37 to 0.68 +/- 0.12 respectively (mean +/- s.e, p less than 0.005) in the fetal distressed group compared with those of the controls. From these results, it may be concluded that the cord artery, which is known as the patent source for the production of PGE2 and prostacyclin, did exert a sufficiently strong reaction to overcome the undesirable haemodynamic changes to maintain the fetal well-being in utero.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

Effect of proximal and distal coronary pressure change on the resistance of stenotic coronary segment.

While dynamic changes in the resistance of stenotic coronary segments were recently proposed by several investigators, the mechanisms of these changes are obscure. This study was conducted to correlate changes in coronary pressure distal to the stenosis to dynamic changes in the stenosis resistance in the canine heart. Coronary pressure distal to the stenosis was raised by either proximal aortic pressure elevation or intracoronary blood infusion distal to the stenosis. The pressure rise resulted in a significant fall in the stenosis resistance. Distal coronary pressure drop induced by phlebotomy or removal of blood from the distal coronary bed caused the reverse effects on resistance. Linear regression analysis revealed a close relationship between changes in distal coronary pressure (delta DCP) and those in resistance of the stenotic coronary segment (delta RL) represented by the following equation; delta RL (dyne X cm-5 X sec X 10(-3)) = 0.50 X [delta DCP (mmHg)]-6.0 X 10(-2), r = 0.86, p less than 0.01. The results suggest that dynamic changes in stenosis resistance appear largely to be a function of the pressure changes distal to the stenosis.

Animals↗
PubMed1986

Immunohistochemical demonstration of HNK-1-defined antigen in gynecologic tumors with argyrophilia.

Gynecologic tumors with argyrophilia were tested immunohistochemically for reactivity with monoclonal antibody HNK-1, which detects normal and neoplastic cells derived from the neuroectodermal and the amine-precursor-uptake and decarboxylation (APUD) systems. The tumors included six small cell carcinomas and four adenocarcinomas of the cervix; 23 adenocarcinomas of the endometrium (13 with type I and 10 with type II argyrophil cells); and 11 mucinous tumors (three benign, three borderline, and five malignant), eight endometrioid carcinomas (four with type I and four with type II argyrophil cells), and two carcinoid tumors (one insular and one strumal) of the ovary. HNK-1 reactive cells were found in almost every category of tumor: in four small cell carcinomas and two adenocarcinomas of the cervix; 11 adenocarcinomas of the endometrium (eight with type I and three with type II argyrophil cells); and four mucinous (two benign and two borderline), two endometrioid (one with type I and one with type II argyrophil cells), and two carcinoid tumors of the ovary. These cells corresponded to at least some of the type I argyrophil cells in endometrial and ovarian endometrioid carcinomas and to similar cells in mucinous and carcinoid tumors of the ovary and small cell carcinoma and adenocarcinoma of the cervix. However, the remaining type I and similar argyrophil cells and almost all type II argyrophil cells were HNK-1 negative, and some of the nonargyrophil tumor cells were HNK-1 positive. Although the significance of such discrepancies in reactivity with HNK-1 antibody remains unknown, the present results suggest that some of the gynecologic tumors with argyrophilia are related to APUDomas.

Antigens, Neoplasm↗
PubMed1986

Hemodynamic effects of labetalol in the dog. Comparative study in the anesthetized open-chest dog and in the conscious dog.

Hemodynamic effects of labetalol, an alpha- and beta-adrenoceptor blocking drug, were investigated in the conscious dog and in the anesthetized open-chest dog. In the conscious dog, intravenous injection of labetalol, in a dose of 0.5 mg/kg, decreased the total peripheral resistance by approximately 20% (P less than 0.01) in association with falls in blood pressure and heart rate. The total peripheral resistance of the anesthetized open-chest dog was not affected by labetalol in the presence of the same extent of blood pressure fall as results of the conscious dog. In contrast, agents which have beta-adrenoceptor blocking effect alone provided substantial elevation of the total peripheral resistance in the anesthetized dog. These results indicate that the different responses of the resistance to labetalol probably result from the vascular alpha-adrenoceptor blocking action, and also show that in the conscious state alpha-adrenoceptor blocking action of labetalol is enhanced in comparison with the effect in the anesthetized open-chest dog.

Adrenergic beta-Antagonists↗
PubMed1986

[Immunohistological demonstration of peptide hormones and serotonin in ovarian mucinous and endometrioid tumors with argyrophil cells].

The localization of peptide hormones and serotonin in ovarian mucinous and endometrioid tumors with argyrophil cells was examined by immunohistochemistry. All of the 15 mucinous tumors had argyrophil cells which resemble the enterochromaffin cells seen in the gastrointestinal tract, and peptide hormones such as gastrin and somatostatin were found in 3 of 5 benign, in 3 of 5 borderline, and in all of 5 malignant tumors. Serotonin was found in 4 benign, 3 borderline and 2 malignant tumors. Of 19 endometrioid adenocarcinomas, type I argyrophil cells which resemble enterochromaffin cells were found in 4 tumors, type II argyrophil cells which contain argyrophil granules mainly in the apical portion or throughout the whole cytoplasm were found in 14, and mixed type cells were found in one. Somatostatin-positive cells were found only in type I cells of a tumor with mixed type argyrophil cells. Serotonin-positive cells were found in 3 tumors containing type I cells. The results obtained were discussed in the comparison with those of cervical and endometrial adenocarcinomas of the uterus. In conclusion, the present study suggests that type I or similar argyrophil cells in ovarian tumors may have endocrine activity.

Adenocarcinoma↗
PubMed1986

Enhanced expression of HLA antigens on gynecologic cancer cells by interferon-gamma.

With flow-cytometry we tested whether or not interferon can induce surface expression of HLA-ABC antigen on cell lines derived from various gynecologic cancers. The tumor cell lines used were Hela S3 derived from cervical cancer, OVK-18 derived from ovarian cancer, HHUA derived from endometrial cancer, SCH, JaR and BeWo derived from choriocarcinoma. 1000 IU/ml of interferon-gamma induced HLA-ABC antigen expression on Hela S3, OVK-18 and SCH but not on BeWo. HLA-ABC antigen was expressed on neither the surface of HHUA or JaR nor was its appearance induced by interferon. The clinical application of interferon may be effective in killing some tumors, taking advantage of the increased expression of HLA antigen.

Cell Line↗
PubMed1986

[Comparison of continuous venous infusion of 5-FU and FT-207 under total parenteral nutrition].

Yoshida sarcoma-bearing rats were continuously infused with 5-FU at a dose of 20 mg/kg/day, and FT-207 at a dose of 40 mg/kg/day, 100 mg/kg/day or 140 mg/kg/day under TPN. After 4 days, rats were sacrificed and the 5-FU and FT-207 concentrations in their organs were measured. The 5-FU level in the tumor was almost the same at when 5-FU was injected at 20 mg/kg/day and FT-207 at 140 mg/kg/day. This 5-FU level in the tumor was twice and four times higher than that of the group injected with FT-207 at 100 mg/kg/day and 40 mg/kg/day. The 5-FU level in the tumor in all four groups was almost twice as high as that in the stomach, intestine and kidney, 7-10 times higher than that in the liver, and 10-30 times higher than that in serum. The FT-207 levels in the alimentary tract, kidney, tumor and serum were almost the same. The conclusion of our preliminary research is that FT-207 is recommended for use in continuous infusion at 7 times the dose of 5-FU when injected under TPN.

Animals↗
PubMed1986

[Clinical effect of prostaglandin F2 alpha on postoperative bowel movement in transurethral and transretroperitoneal urologic surgery].

The clinical effectiveness of prostaglandin F2 alpha (PGF2 alpha) injection on postoperative bowel movement was studied in 455 patients who underwent transurethral and transretroperitoneal operation. The patients were divided into two groups, 417 patients with PGF2 alpha injection and 38 without injection. 1,000 micrograms of PGF2 alpha were infused twice a day postoperatively until the onset of active flatus. The onset of flatus was recorded in each group. The onset of flatus after operation was 15 hours and 47 minutes for the injection group of 194 patients operated transurethrally, which was shorter than the 21 hours and 50 minutes for the uninjected group (p less than 0.01), but the onset of flatus was not significantly affected by the injection in the patients operated transretroperitoneally. Postoperative PGF2 alpha infusion facilitated flatus in the patients undergoing transretroperitoneal urologic surgery which took 1 and a half hours or more in doing so (p less than 0.05). Generally, postoperative paralytic ileus was milder after urological surgery than after bowel surgery, but PGF2 alpha injection was effective clinically both in transurethral surgery and transretroperitoneal surgery.

Adult↗