Biomedical subjects

K Miyata

Publications and source records attributed to K Miyata.

At least 271 records · Page 15Linked to original sources

PubMed1992

A YIGSR-containing novel mutein without the detrimental effect of human TNF-alpha of enhancing experimental pulmonary metastasis.

The injection of B16F10 melanoma cells with recombinant human tumor necrosis factor alpha (TNF-alpha) into the tail vein of C57BL/6 mice resulted in 2- to 25-fold more metastatic foci in the lungs than the injection of tumor cells alone. Clearly, TNF-alpha significantly enhanced experimental tumor metastasis. Furthermore, it enhanced the metastasis of Lewis lung carcinoma cells. In contrast, a mutein of TNF-alpha, designated as F4236, having the cell-adhesive sequence (Tyr-Ile-Gly-Ser-Arg) at the N-terminus of the TNF molecule did not enhance metastasis, but rather exhibited similar antitumor activity to wild-type TNF-alpha in fibrosarcoma-bearing mice.

Amino Acid Sequence↗

PubMed1992

A sero-epidemiological study on mother-to-child transmission of HTLV-I in southern Kyushu, Japan.

In vertical transmission of HTLV-I the duration of breast-feeding seems to be an important risk factor. In this study, we made prospective and retrospective surveys on the rate of vertical transmission of HTLV-I in infants and their siblings born to HTLV-I seropositive mothers. The results obtained were as follows. (1) In the prospective study, 885 of the 16,283 pregnant women examined were HTLV-I seropositive, and the seropositive rate was 5.4%. The seroconversion rates of short-term (< 7 months) and long-term (> or = 7 months) breast-feeders were 3.8% (1/26 cases) and 25.0% (1/4 cases) respectively, and the rate of bottle-feeders was 5.6% (10/177 cases). Short-term breast-feeding tended to yield a lower seroconversion rate of infants. In addition, the seroconversion rate of short-term breast-feeders was nearly equal to that of bottle-feeders: 3.8% vs. 5.6%. (2) In the retrospective study, the seroconversion rates of short-term and long-term breast-feeders in their siblings were 4.5% (3/67 cases) and 14.0% (19/136 cases) respectively. There was a significant difference between the 2 groups (p < 0.01). Thus, the results of our retrospective and prospective studies suggest that short-term breast-feeding might lessen the risk of breast-milk-borne transmission of HTLV-I from carrier mothers to their children.

Adult↗

PubMed1992

[Quantitative analyses of the normal throat flora of children with upper respiratory tract infections].

Relationship between the normal throat flora and pathogenic bacteria recovered from the throat in 139 children with upper respiratory tract infections in winter were studied using quantitative analyses. Pathogenic bacteria examined include S. pyogenes, H. influenzae, S. aureus, and S. pneumoniae, and the normal floras include alpha-streptococci, gamma-streptococci, Neisseria species, and Micrococci. Children with S. pyogenes in their throats (S. pyogenes group) were examined with anti-streptococcal antibodies such as anti-streptolysin O, anti-streptokinase, and anti-deoxyribonuclease B. Eighty seven pathogenic bacteria were recovered from 72 children (51.8%) out of 139. S. pyogenes and S. pneumoniae groups showed significantly lower alpha-streptococci and gamma-streptococci in incidence of appearance when compared with children with the no pathogenic bacteria in their throats (no bacteria group). H. influenzae group showed significantly lower gamma-streptococci and higher Neisseria sp. in incidence of appearance compared with the no bacteria group. Positive cases for anti-streptococcal antibodies showed a significantly lower alpha-streptococci in number compared with negative cases for antibodies and the no bacteria group, and a significantly lower gamma-streptococci in incidence of appearance compared with the no bacteria group. These data suggest that the normal throat flora may have a role in prevention of colonization by the pathogenic bacteria in vivo, as were shown in vitro by many authors, and that the quantitative analysis of the normal flora is useful because this methodology might reveal whether the bacteria recovered from the throat show the pathogenicity.

Adolescent↗

PubMed1992

L-365,260, a potent CCK-B/gastrin receptor antagonist, suppresses gastric acid secretion induced by histamine and bethanechol as well as pentagastrin in rats.

We evaluated the effects of a potent cholecystokinin (CCK)-B/gastrin receptor antagonist, L-365,260 (3R(+)-N-(2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin - 3-yl)-N'-( 3-methylphenyl) urea); a selective CCK-A receptor antagonist, devazepide (L-364,718); and cimetidine on gastric acid secretion induced by pentagastrin, histamine and bethanechol in anesthetized rats. We also evaluated the effects of L-365,260 and cimetidine on acid secretion in pylorus-ligated rats. Intravenous administration of L-365,260, L-364,718 and cimetidine dose-dependently reduced acid secretion induced by pentagastrin (20 nmol/kg/hr), with ED50 values of 0.63, 19.1 and 2.5 mumol/kg, respectively. Of interest was the finding that L-365,260, like cimetidine, dose-dependently inhibited acid secretion induced by histamine (100 mumol/kg/hr) and bethanechol (5 mumol/kg/hr) with ED50 values of 5.9 and 4.3 mumol/kg, respectively. L-364,718, even at 30 mumol/kg, i.v., had only a slight effect on histamine- or bethanechol-induced acid secretion. Gastric acid secretion was suppressed by treatment with L-365,260 (3-100 mumol/kg, i.v.) and cimetidine (11.9-396.4 mumol/kg, i.v.) in pylorus-ligated rats, with ED50 values of 13.3 and 96.9 mumol/kg, respectively. These results indicate that L-365,260 suppresses acid secretion induced by histamine and bethanechol in rats and that the gastrin receptor plays an important role in acid secretion in pylorus-ligated rats.

Animals↗

PubMed1992

[Cryopreservation of spermatozoa of a transgenic mouse].

Spermatozoa of a homozygous transgenic mouse, in which the firefly luciferase gene was expressed under the control of beta-actin promoter, were frozen at -196 degrees C. One fourth of the frozen sperm was later thawed and used for in vitro fertilization. Thirty-six of 65 oocytes (55.4%) developed to the 2-cell stage. All the 2-cell embryos were transferred to the oviducts of pseudopregnant recipients and 23 young (63.9%, 23/36) were born. All of young analyzed carried the transgene and showed the luciferase gene expression.

Actins↗

PubMed1992

[A case of malignant rheumatoid arthritis with corticosteroid-reactive subacute myelopathy and multiple peripheral neuropathy].

We reported a 64-year-old man who had malignant rheumatoid arthritis (MRA) and developed subacute myelopathy and peripheral neuropathy. He had suffered from seropositive rheumatoid arthritis for 4 years, and developed weakness of four limbs, dysuria and constipation two months before the admission. Neurological examination revealed the diffuse muscle wasting and weakness in four limbs. Deep tendon reflexes were hyperactive in four limbs, but not in jaw jerk. Babinski sign was positive bilaterally. Deep sensation was decreased in four limbs and superficial sensation was decreased below the neck. Dysuria and constipation were noted, but anal and bulbocavernosus reflexes were present. On laboratory examination, RF and RAHA increased markedly. Serum complements decreased and immune complexes were positive. Nerve conduction study demonstrated multiple entrapment neuropathy in addition to mononeuritis multiplex. Histological examination of the biopsied sural nerve disclosed the obliterating endarteritis in the epineurium, and marked decrease in number of myelinated fibers. No compressive lesions were seen in the spinal canal by spine X-ray and MRI. Assuming that inflammatory process induced cervical myelopathy, corticosteroid therapy (predonisolone 60 mg/day) was administered and alleviated neurological symptoms, in accordance with the improvement of serological abnormalities. Therefore, an inflammatory process associated with MRA was supposed to damage the spinal cord as well as peripheral nerves in the present case.

Acute Disease↗

PubMed1992

Characterization of YM060, a potent and selective 5-hydroxytryptamine3 receptor antagonist, in rabbit nodose ganglion and N1E-115 neuroblastoma cells.

The 5-hydroxytryptamine (5-HT)3 receptor blocking properties of YM060, [(R)-5-[(1-methyl-3-indolyl)carbonyl]-4,5,6,7-tetrahydro-1H- benzimidazole hydrochloride], were examined by electrophysiological and radioligand binding studies. Results were compared with those for ondansetron, granisetron and the enantiomer (S-form) of YM060. 5-HT and 2-methyl-5-HT, a selective 5-HT3 receptor agonist, induced dose-dependent depolarizations of rabbit nodose ganglion with ED50 values of 24.0 (19.9-29.1) and 40.1 (30.9-52.1) nmol, respectively (geometric mean, 95% CL). YM060, ondansetron, granisetron and the S-form dose-dependently inhibited 5-HT-induced depolarizations with IC50 values of 3.85 (2.47-5.98), 1.55 (1.26-1.91), 1.45 (1.18-1.79) and 13.5 (11.2-16.2) nM, respectively. Methysergide, a 5-HT1-like and 5-HT2 receptor antagonist, at a concentration of 10(-5) M had no effect on responses to 5-HT. YM060 up to 10(-5) M produced no significant depression of depolarizing responses to 1,1-dimethyl-4-phenylpiperazinium iodide and gamma-aminobutyric acid. YM060, ondansetron, granisetron and the S-form displaced specific binding of [3H]GR65630 to N1E-115 neuroblastoma cell membranes with Ki values of 0.091 (0.086-0.097), 7.03 (5.96-8.01), 2.02 (1.74-2.30) and 10.3 (9.96-10.6) nM, respectively. These results show that YM060, compared with ondansetron and granisetron, has considerably higher affinity for 5-HT3 receptors in N1E-115 cells and slightly less potent 5-HT3 receptor antagonistic activity in rabbit nodose ganglion. Moreover, the isomeric activity ratio (R-form/S-form) was approximately 112 in N1E-115 cells and no greater than 4 in the ganglion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

[Recurrence and survival rate of advanced gastric cancer after preoperative cisplatin intra-arterial injection therapy].

In our department, curative operations were performed for 49 patients with resectable advanced gastric cancer from Jan. 1988 to Feb. 1990. Among these patients, preoperative intra-arterial therapy using cisplatin (40 or 60 mg) was done for 17 patients. In this report, recurrence and survival rate of these patients were investigated. Survival rate of patients with preoperative intra-arterial injection therapy 42 months after operation was 56.15%, while that of patients without preoperative intra-arterial injection therapy was 56.62%. There were no significant differences between these two groups. And two peritoneal disseminations and one brain metastasis were seen in patients with preoperative intra-arterial injection therapy (recurrence rate, 17.6%), but no liver metastasis and local recurrence were noted. Seven recurrences were observed in patients without pre-operative intra-arterial CDDP injection therapy (local 3, liver 3, peritoneal dissemination 1, recurrence rate, 21.2%). We have already reported that much platinum accumulated in gastric cancer tissue and regional lymph nodes. This high accumulation of cisplatin can be the reason why no local recurrence was seen in patients with preoperative intra-arterial injection therapy. In conclusion, preoperative intra-arterial injection therapy using cisplatin may be an effective method to prevent postoperative local recurrence of resectable advanced gastric cancer.

Brain Neoplasms↗

PubMed1992

[Superior mesenteric arterial infusion chemotherapy in patient with both peritoneal carcinomatosis and liver metastasis].

Experimental study of superior mesenteric arterial infusion chemotherapy was done to evaluate the effect of this therapy on metastatic liver tumor. This treatment has been tried clinically for ileus caused by peritoneal carcinomatosis with good result. Moreover, the infused drug is expected to reach the liver via portal route, just like intraportal administration. This study disclosed that superior mesenteric arterial infusion made for a sufficiently high 5-FU concentration of portal blood but the concentration in the metastatic liver tumor was lower when compared with intravenous infusion. However, because the 5-FU concentration in blood of the aorta was lower than in the intravenous administration group, our method may decrease the unfavorable side effects of anti-cancer drugs.

Animals↗

PubMed1992

[A patient with liver cirrhosis manifesting various symptoms including cerebellar ataxia due to germanium intoxication].

A patient with hepatitis B virus-associated cirrhosis manifested various symptoms such as anemia, renal damage and neurological signs including cerebellar ataxia due to long-term administration of germanium-containing food. The patient was a 40-year-old male who had taken germanium containing mineral cheese for 26 months after he was diagnosed as having cirrhosis. Twenty four months after beginning to take the mineral cheese, he began manifesting paresthesia of the extremities, dysarthria and gait ataxia. Laboratory findings revealed anemia and renal damage. Biopsy of the peripheral nerve revealed loss of the large sheathed nerve, a characteristic feature of germanium intoxication. A high concentration of germanium (GeO2) was detected in patient's hair and urine. Cerebellar ataxia was characteristic in this patient, which was not reported in the previous papers.

Adult↗

PubMed1992

Role of the serotonin3 receptor in stress-induced defecation.

The possibility that 5-hydroxytryptamine (serotonin; 5-HT) mediates bowel dysfunction caused by stress was evaluated in rats and mice treated with 5-HT or thyrotropin-releasing hormone (TRH) injection and in rats subjected to stress. Restraint stress at room temperature (23 degrees C) significantly increased fecal pellet output without the formation of gastrointestinal mucosal lesions in free-feeding rats, and caused diarrhea in 90 to 100% of animals within 3 hr in food-deprived rats. Oral YM060, ondansetron, granisetron, atropine and diazepam and s.c. tetrodotoxin inhibited these stress-induced changes in bowel function in fed and fasted rats. ED50 values were 1.1 (0.2-6.6) and 2.5 (1.1-5.7) micrograms/kg for YM060, 483 (338-691) and 354 (262-477) micrograms/kg for ondansetron, 208 (111-393) and 142 (48.9-414) micrograms/kg for granisetron, 811 (639-1,030) and 847 (641-1,118) micrograms/kg for atropine, 3,099 (1,499-6,405) and 5,396 (4,768-6,106) micrograms/kg for diazepam and 1.9 (1.7-2.1) and 3.3 (1.6-6.5) micrograms/kg for tetrodotoxin, respectively. Methysergide inhibited stress-induced diarrhea with an ED50 value of 724 (384-1,366) micrograms/kg s.c., whereas it had partial effect on stress-induced increases in fecal pellet output. Exogenous 5-HT increased fecal pellet output in rats and caused diarrhea in mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

[Corneal endothelial cell damage in penetrating keratoplasty].

Fifty-eight corneal grafts were investigated by specular microscopy to determine the corneal endothelial damage in penetrating keratoplasty. The center of the donor corneal endothelium was examined before and after 2 weeks, 1, 3, 6 and 12 months after surgery. The cell density decreased periodically during the observation period, and the endothelial cell loss in all the cases averaged 10. 4% at 2 weeks after the operation, 16.0% at 1 month, 33.0% at 3 months, 39.4% at 6 months, and 48. 2% at 12 months. However, the cell loss in the keratoconus subgroup averaged -1.9%, 1.2%, 9.9%, 30. 6%, and 33.4% corresponding to the above period. The least cell loss among the diagnostic subgroups was in the keratoconus, followed by corneal leukoma. The cell loss in bullous keratopathy was higher than in keratoconus and corneal leukoma case. It was concluded that the cell loss in penetrating keratoplasty during the first postoperative year depends on the primary disease.

Adolescent↗

PubMed1992

[Acute nongonococcal epididymitis--pharmacological and therapeutic aspects of levofloxacin].

We performed basic and clinical studies on the effects of a new oral quinolone derivative, levofloxacin (LVFX, Code No. DR 3355) which is an optical l-isomer of ofloxacin, in acute epididymitis. LVFX was administered in a dose of 200 mg to prostatic cancer patients 2 hours before operation. The mean concentration of LVFX in the tissues of testis and epididymis were 4.73 micrograms/g and 313-3.6 micrograms/g, respectively. Tissue/Serum ratios were 1.63 and 1.16-1.32, respectively. LVFX was administered in a dose of 100 mg three times daily for 13 days to healthy male volunteers. Semen and blood samples were taken 2 hrs after 7th and last day of administration. The concentration of LVFX in semen were 1.19 micrograms/ml (7th day) and 1.32 micrograms/ml (13th day). Semen/serum ratios were 1.12 and 1.26, respectively. No affection of LVFX on the sperm was observed. Antimicrobial activity of LVFX to C. trachomatis showed good MICs of 0.25-1.0 micrograms/ml. LVFX was administered in a dose of 100 mg two or three times daily for 14 days to 23 patients with acute epididymitis. The overall efficacy rate based on a criteria for acute epididymitis showed 100% (excellent: 16, good: 4, 20/20). A better efficacy rate was obtained on the 14th day than 7th day. No subjective or objective adverse reactions were observed.

Acute Disease↗

PubMed1991

Inhibitory effect of maternal antibody on mother-to-child transmission of human T-lymphotropic virus type I. The Mother-to-Child Transmission Study Group.

In order to evaluate the protective role of the maternal antibody against mother-to-child transmission of HTLV-I, we followed a total of 780 children born to HTLV-I carrier mothers by investigating the level of anti-HTLV-I antibody transferred in utero, decline of the maternal antibody and seroconversion in post-natal life. The anti-HTLV-I antibody was positively detected within the first 3-6 months of life and declined at 6-12 months after birth in all children. After the maternal antibody declined, seroconversion occurred in some of the children following either breast feeding or bottle feeding. The seroconversion rates of short-term (less than or equal to 6 months) and long-term (greater than or equal to 7 months) breast feeders were 4.4% (4/90 cases) and 14.4% (20/139 cases), and the rate of bottle feeders was 5.7% (9/158 cases). Long-term breast feeding yielded more seroconverters than short-term breast feeding; 14.4% (20/139 cases) vs. 4.4% (4/90 cases), RR = 3.68, p = 0.018. The seroconversion rate of short-term breast feeders was nearly equal to that of bottle feeders; 4.4% (4/90 cases) vs. 5.7% (9/158 cases), RR = 0.770, p = 0.471. When neonatal lymphocytes were cultured with breast milk cells of HTLV-I carrier mothers, the in vitro infection of HTLV-I was inhibited by the addition of HTLV-I-seropositive cord-blood plasma. Our results suggest that the maternal antibody may inhibit HTLV-I infection by short-term breast feeding but not by long-term breast feeding after decline of the maternal antibody.

Adolescent↗

PubMed1991

CO2 laser-induced pain-related somatosensory evoked potentials in peripheral neuropathies: correlation between electrophysiological and histopathological findings.

Pain-related somatosensory evoked potentials (pain SEPs) following CO2 laser stimulation as well as conventional electrically stimulated SEPs (electric SEPs) were examined in 10 patients with peripheral neuropathies in whom the histopathological examination of the sural nerve was done. Results of pain SEPs showed a positive relationship with clinical impairment of pain sensation and densities of small myelinated fibers of the sural nerve. In contrast, results of electric SEPs showed a positive relationship with clinical impairment of deep and tactile sensations and with densities of large myelinated fibers of the sural nerve. Therefore, pain SEPs are considered to be generated by ascending signals mediated through nociceptive receptors and A delta fibers. The pain SEP is only one noninvasive and objective method currently available to investigate a physiological condition of the sensory pathway responsible for pain sense, and is especially useful when combined with the conventional electric SEPs.

Adolescent↗

PubMed1991

Doppler echocardiographic evaluation of an infant with HCM during ACTH therapy.

Adrenocorticotropic hormone (ACTH) therapy is useful in the treatment of patients with West syndrome, and hypertrophic cardiomyopathy (HCM) in association with ACTH therapy has recently been reported. We describe the Doppler echocardiographic evaluation of an infant who had West syndrome and HCM. ACTH therapy produced increases in the interventricular septal thickness, the pressure gradient of the left ventricular outflow tract, and the heart rate. Doppler echocardiographic examination was found to be much more sensitive for monitoring the cardiac changes than either 2-dimensional echocardiography or the heart rate.

Adrenocorticotropic Hormone↗

PubMed1991

[Nosocomial infections due to methicillin-resistant S. aureus (MRSA) at the Kagoshima University Hospital (1). Coagulase typing of MRSA].

Nosocomial infection due to MRSA at the Kagoshima University Hospital and their coagulase typing were examined using S. aureus (349 strains) clinically isolated in 1989. The results were as follows: 1) S. aureus consisted of 43.6% of MRSA and 56.7% of Methicillin-sensitive S. aureus (MSSA). 2) MRSAs were recovered most frequently from the specimens from the respiratory tract (47.8%). 3) The isolation of MRSA gradually increased in frequency from January to August; however, that of MSSA did not show a similar tendency. 4) The isolation of MRSA was higher in frequency in the surgical wards, the ICU and the pediatric ward. 5) When classified into 8 coagulase types, MRSAs (133 strains) consisted of only 3 types (54.1% of type II, 32.3% of type VII, and 12.0% of type IV), whereas MSSAs contained all coagulase types. As compared with the results of coagulase typing at other institutions, the incidence of type VII was much more frequent at our hospital. 6) A few coagulase types of MRSA appeared in each ward. Also, type II MRSA strains increased in June and July, and type VII MRSA increased in August. However, MSSA strains did not show any similar tendency.

Bacterial Typing Techniques↗

PubMed1991

[Nosocomial infections due to methicillin-resistant S. aureus (MRSA) at the Kagoshima University Hospital (2). Susceptibility to antibiotics].

Susceptibility to antibiotics of 123 MRSA strains isolated at the Kagoshima University Hospital in 1989 was examined. The results were as follows: 1) Susceptibility of MRSA strains was excellent to VCM, MINO, and RFP, followed by IMP, CLDM, and CPFX. However, most strains were resistant to PCG, MPIPC, ABPC, CET, CMZ, CZON, GM, and AMK. 2) Five strains highly resistant to RFP were isolated. Three of these strains were isolated on the ward for tuberculosis. This suggests easy development of resistance to RFP by MRSA. 3) Differences in susceptibility to antibiotics between coagulase type II and type VII strains were examined. The cumulative percentage of type II strains susceptible to CLDM (MICs less than 0.5 microgram/ml) was 15.3%, and that of type VII was 45.2%. Strains resistant to CLDM were more frequently isolated among type II than among type VII strains (p less than 0.001). A similar relationship between strains and antibiotics was also found with EM and CPEX. On the other hand, the cumulative percentage of type II strains susceptible to AMK (MICs less than 25 micrograms/ml) was 89.7%, and that of type VII was 9.7%. Strains resistant to AMK were more frequently isolated among type VII than among type II strains (p less than 0.001).

Anti-Bacterial Agents↗