Search PubMed⌕ Search

Biomedical subjects

K Goto

Publications and source records attributed to K Goto.

At least 829 records · Page 46Linked to original sources
PubMed1986

[Restorative effect of traxanox on the suppression of antibody production in BALB/c mice].

The number of spleen-rosette forming cells (RFC) and thymus-RFC was assayed on day 4 after immunization with 5 X 10(8) sheep red blood cells (SRBC) in BALB/c mice. The number was decreased significantly by oral administration of cyclophosphamide (20 mg/kg) on days--1 and 0. The decrease in spleen-RFC and thymus-RFC by the pretreatment with cyclophosphamide was significantly restored or had a tendency to be restored by traxanox at doses of 3 and 30 mg/kg (p.o.). In addition, traxanox (30 mg/kg, p.o.) protected the reduced number of RFC in mice treated with cyclophosphamide (3 mg/kg, p.o.). Traxanox (30 mg/kg, p.o.) restored the decreased number of spleen-RFC and thymus-RFC in mice pretreated with dexamethasone (0.1 mg/kg, p.o.), and protected the decrease in the RFC in mice treated with prednisolone (10 mg/kg, p.o.). Also, phagocytosis of SRBC by the spleen adherent cells obtained from mice treated with dexamethasone (0.1 mg/kg, p.o.) was inhibited markedly in comparison with that by the spleen adherent cells of untreated mice. The transfer of the spleen adherent cells treated with dexamethasone into syngeneic recipient mice had no effect on the number of spleen hemolytic plaque forming cells (HPFC). On the other hand, the inhibition of phagocytosis of SRBC by spleen adherent cells of mice pretreated with dexamethasone was restored by the addition of traxanox (10 and 30 microM). The transfer of the spleen adherent cells treated with traxanox resulted in an increase in HPFC number. Traxanox (30 mg/kg, p.o.) protected the decrease in spleen-RFC and thymus-RFC in mice treated with indomethacin 1 mg/kg, p.o.) or acetylsalicylic acid (300 mg/kg, p.o.). Traxanox (3-30 mg/kg, p.o.) restored the decreased number of HPFC, spleen-RFC and thymus-RFC in mice pretreated with carrageenan (0.03 mg). The suppression of phagocytosis of SRBC by spleen adherent cells was restored by the treatment with traxanox (3 and 30 microM). The transfer of the spleen adherent cells treated with traxanox also resulted in an increase in HPFC count. These results strongly suggest that traxanox restores the artificially suppressed immune responses via macrophages.

Adjuvants, Immunologic↗
PubMed1986

Analysis of new imidazoline derivative-induced increase in the maximum response to norepinephrine in the rat vas deferens.

The effects of newly synthesized 5-imidazoline derivatives on the dose-response relationship to norepinephrine were investigated in the normal and denervated vasa deferentia of the rat. Three derivatives (K-3827, K-4011 and K-4300) exerted alpha-antagonistic action, the potency of which was similar to that of tolazoline. The pA2 values of these derivatives and currently known alpha-antagonists (tolazoline, phentolamine and prazosin, but not yohimbine) in the denervated tissue were slightly but significantly larger than those in the normal tissue. All imidazoline derivatives and alpha-antagonists produced an increase in the maximum response to norepinephrine in the normal vas deferens. In the denervated tissue, however, K-3827, K-4011 and alpha-antagonists caused only a rightward shift of the dose-response curve to norepinephrine, but not an increase in the maximum response, i.e., relatively pure alpha-antagonism. In contrast, the other 3 imidazoline derivatives, K-4299 and K-6342 which exhibited neither alpha-agonistic nor antagonistic action and K-4300, increased the maximum response to norepinephrine even after denervation. Their effects were nonspecific in that they also potentiated acetylcholine-induced contractions in both normal and denervated tissues. These 3 imidazoline derivatives antagonized the action of diltiazem. The effects of imidazoline derivatives and alpha-antagonists were discussed in relation to those of denervation, and the drug enhancement by 3 imidazoline derivatives was analyzed from the viewpoint of calcium movement.

Acetylcholine↗
PubMed1986

The effects of extracellular calcium removal on sino-atrial node cells treated with potassium-depleted solutions.

The effect of extreme calcium reduction was studied in rabbit sino-atrial node cells treated with K-free media. Ca removal (Ca = 0, EGTA = 6 mM) suppressed spontaneous miniature fluctuations elicited by exposure to the K-free media. Further, successive exposure to the Ca-free, EGTA solutions produced a propagated action potential and suppressed a contracture. The action potential was not noticeably altered by tetrodotoxin (TTX). In the presence of normal Ko, reducing the bathing calcium concentration with EGTA prolonged the duration of the action potential. The potential induced by Ca removal was similar to that observed in the K-free media. From these results, we have concluded that a drastic reduction in the extracellular Ca concentration produces a decrease in the overloaded Ca in the cell exposed to the K-free media, resulting in an increase in the amplitude of action potentials.

Action Potentials↗
PubMed1986

Pharmacological analysis of autonomic innervation of the right atria of rats and guinea pigs: demonstration of nonadrenergic noncholinergic nerves.

Transmural nerve stimulation (TNS) of the right atria in vitro produced positive and negative chronotropic responses in rats and guinea pigs. The negative component appeared only temporarily soon after the cessation of TNS and was usually masked by the positive component. The positive and negative chronotropic responses were accompanied by an increase and decrease in contractile force, respectively. Atenolol (3 X 10(-6) M) decreased and atropine (10(-6) M) potentiated the TNS-induced positive chronotropic response. In the presence of both atenolol and atropine, TNS accelerated the heart rate markedly in the right atria of guinea pigs and slightly in those of rats. TNS-induced acceleration of the heart rate was also observed in surgically sympathectomized or reserpine-pretreated (5 mg/kg/48 hr and 2.5 mg/kg/24 hr i.p.) right atrium, in which tyramine (up to 10(-4) M) exerted no appreciable effect. Inasmuch as tetrodotoxin (10(-6) M) almost abolished the TNS-induced chronotropic response, this atenolol- and atropine-resistant response is likely mediated by nonadrenergic noncholinergic (NANC) nerve(s). The NANC nerve-mediated positive chronotropic response was not affected by diphenhydramine (10(-6) M), cimetidine (10(-6) M), methysergide (10(-6) M) and hexamethonium (3 X 10(-6) M). The NANC nerve-mediated response was relatively slow at the onset yet long-lasting compared with adrenergic and cholinergic responses, suggesting that the neurotransmitter of the NANC nerve is a certain substance which may be inactivated more slowly than biogenic amines. Histochemical studies demonstrated the presence of vasoactive intestinal polypeptide-like and substance P-like immunoreactive nerves in the right atrium, as well as catecholamine-fluorescence and acetylcholinesterase-positive nerves.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholinesterase↗
PubMed1986

[Effect of human recombinant-gamma interferon on the immune function of peripheral blood lymphocytes in cancer patients].

We administered recombinant gamma-interferon (ReIFN-gamma) daily to 7 cancer patients, and the effect on the immune function of peripheral blood lymphocytes was studied. Following the administration of ReIFN-gamma, no characteristic changes were observed in leukocyte count, lymphocyte count, OKT4/OKT8 or Leu 7. Natural killer cell cytotoxicity was augmented in all cases from the first week of administration and retained a high level of activity during the period of treatment. In contrast, the blastogenesis of PBL with PHA decreased from the first week. Suppressor cell activity was augmented from the first week and maintained throughout this period. As to clinical effect, two patients who had metastatic liver tumors showed a response to the administration of ReIFN-gamma.

Aged↗
PubMed1986

Radiologic diagnosis of lateral parasellar masses and their classifications.

Computed tomography (CT) and cerebral angiography of lateral parasellar masses were reviewed and classified into 6 categories according mainly to operative findings, as: 1) intradural or dural masses, 2) pituitary fossa masses, 3) intracranial extradural masses, 4) bony or cartilaginous masses, 5) masses of sphenoid sinus origin, and 6) carcinomas. Each of the 6 categories shows characteristic combinations of 3 cardinal radiologic features. These are: a) transverse displacement of the ganglial and cavernous carotid arteries on antero-posterior carotid angiography, b) erosion or destruction of bone in the lateral parasellar region, and c) sphenoid sinus involvement on CT and conventional radiography. Use of this classification scheme based on the 3 cardinal radiologic features described should be of considerable aid in the diagnosis of lateral parasellar masses.

Brain Neoplasms↗
PubMed1986

Treatment of direct carotid cavernous sinus fistulae. Various therapeutic approaches and results in 148 cases.

From 1974 to 1986, 148 patients with carotid cavernous fistula (CCF) were evaluated for intravascular therapy. Four patients died from hemorrhage before treatment could be instituted and the CCF closed spontaneously in 5. Therapeutic approaches which resulted in complete occlusion in the remaining 139 cases were transarterial in 118, transvenous in 15 and external compression of the carotid artery and jugular vein in 6. The current treatment of choice of the direct CCF is intravascular embolization using detachable balloons, particulate emboli or liquid adhesive agents to occlude the CCF while attempting to preserve the carotid artery. In 15 patients it was technically too difficult to use the transarterial approach. The patients were therefore treated from a transvenous approach including access via the femoral vein, superior ophthalmic vein, intraoperatively from the inferior petrosal sinus or direct puncture of the cavernous sinus. Embolic agents used included detachable silicone balloons, steel minicoils, particulate emboli and isobutyl-2-cyanoacrylate. In 14 of these 15 patients total obliteration was achieved with marked improvement in symptoms. Complications occurred in 3 patients including perforation of the cavernous sinus resulting in subarachnoid hemorrhage, delayed pontine hemorrhage from subtotal occlusion of the fistula and transient increased proptosis.

Arteriovenous Fistula↗
PubMed1986

Closure of carotid cavernous sinus fistulae by external compression of the carotid artery and jugular vein.

From 1974-1986, 152 patients with carotid cavernous sinus fistulae (CCF) have been evaluated. Progressive closure of both dural and direct types of CCF have been noted utilizing intermittent external manual compression of the cervical carotid artery and jugular vein. In a group of 71 patients in whom this treatment was attempted, we have observed that 7 of 23 patients (30%) with dural CCF, and 8 of 48 patients (17%) with direct CCF had complete closure of their fistulae with no recurrence either clinically or at angiography done one year later. Closure occurred at varying times, from several minutes to 6 months (mean 41 days) following compression therapy. In those patients with CCF without rapidly progressive visual deterioration, cerebral ischemia, or other complicating factors, we recommend this technique with serial clinical follow-up and angiography before more definitive therapy is employed.

Adolescent↗
PubMed1986

Cervical carotid artery aneurysms and pseudoaneurysms. Treatment by balloon embolization therapy.

The treatment of high cervical carotid artery aneurysms and pseudoaneurysms is often difficult due to relative surgical inaccessibility. We are currently managing such lesions by detachable balloon embolization therapy. In 7 patients with acute cervical carotid pseudoaneurysms, the carotid artery was occluded by a trapping procedure above and below the lesion using detachable silicone balloons. In 3 patients with aneurysms that had well organized walls, a detachable balloon was placed directly within the aneurysm, inflated to exclude it from the circulation, and then detached. The carotid artery was therefore preserved.

Adult↗
PubMed1986

Intravascular detachable balloon embolization of intracranial aneurysms. Indications and techniques.

The treatment of intracranial aneurysms from a transvascular approach, with preservation of the parent vessel is now being performed in selected cases. From a transfemoral approach, a silicone detachable balloon is flow-directed up the carotid or vertebral-basilar artery, guided directly into the aneurysm and detached. The aneurysm is thus excluded from the circulation and the parent artery is preserved. Thus far, this technique has been successful in treating aneurysms in the cavernous carotid, carotid ophthalmic, posterior communicating, distal basilar, and posterior cerebral artery distributions. The indications and techniques of detachable balloon embolization therapy are presented.

Embolization, Therapeutic↗
PubMed1986

[The influence of weight loss on the reproductive function of the female rat: changes in the estrous cycle and hypothalamo-pituitary-ovarian function during feed restriction and subsequent refeeding period].

Twelve-week-old female SD rats were restricted to an 8 g/day feed intake for 2 months followed by feeding ad libitum for 3 weeks. Feed restriction resulted in weight loss and constant diestrous. A persistent increase in the hypothalamic GnRH content was observed during the underfed period. Serum LH and PRL levels dropped throughout the period but the initial reduction in the serum FSH level was observed on the 60th day. The reductions in the pituitary content of these hormones were observed on the 30th day. The decrease in the serum and ovarian E2 levels were detected on the 14th day. Anterior pituitary showed a significant response to GnRH + TRH during the course, and the relative increases in LH, FSH and PRL were greater than those in the pretreatment rats. In the course of refeeding, the body weight returned to the control level and regular estrous cycles were reestablished on the 15th and 21st day, respectively. Elevated hypothalamic GnRH content returned to the control level on the 16th day. The changes in the pituitary-ovarian axis were prompt rebound rises in serum FSH and PRL levels and pituitary FSH content, delayed restoration of serum and pituitary LH levels and serum and ovarian E2 levels, and a marked increase in the serum and ovarian progesterone levels on the 16th day. The relative increases in FSH and PRL after GnRH + TRH injection were smaller than those in the underfed period.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗