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Biomedical subjects

Y Miyata

Publications and source records attributed to Y Miyata.

At least 181 records · Page 10Linked to original sources

[Beneficial effect of steroid pulse therapy on Wernicke-Korsakoff syndrome due to hyperemesis gravidarum].

A 25-year-old woman suffered from hyperemesis gravidarum when she was seven weeks pregnant. Since her vomiting continued, she received intravenous dextrose and electrolytes without thiamine in a hospital. One month later, she developed gait disturbance, followed by confusion and dysarthria. On admission to our department, she was confusional and had ataxic dysarthria. Spontaneous and gaze evoked nystagmus was present. Limb coordination was bilaterally ataxic. Based on her clinical course and symptoms, she was diagnosed as having Wernicke's encephalopathy. From the admission day, intravenous infusion of vitamin B1 (600 mg/day) was started. A few days later, her consciousness and limb ataxia began to improve. However, truncal ataxia and polyneuropathy became evident. Eight weeks after onset, she developed Korsakoff's psychosis such as anterograde and retrograde amnesia, disorientation and confabulation. We administered large amounts of corticosteroid (methylprednisolone 500 mg/day) in order to reduce brain edema or stabilize the impaired blood-brain barrier. Soon after, her psychosis began to improve gradually. She recovered remarkably from the psychosis, but she was left with persistent nystagmus, mild ataxic gait and polyneuropathy. The present case suggests that corticosteroid may have the beneficial effect on Wernicke-Korsakoff syndrome.

Adult↗

Benign recurrent intrahepatic cholestasis: a long-term follow-up.

We report on a case with a 50-year history of benign recurrent intrahepatic cholestasis, including 33 years of follow-up at our hospital. The attacks of jaundice began at the age of 1 year and have been repeated more than 14 times to date. During the follow-up period at our hospital, the patient has suffered 6 attacks of cholestasis. During the episodes of cholestasis, a dissociation between the serum level of bilirubin and that of bile acids was observed. The analysis of serum bile acids during cholestasis showed that cholic acid and chenodeoxycholic acid were the main bile acids, and no appreciable amounts of the secondary bile acids were detected. Between episodes the liver function tests, including serum bile acids, were normal. Despite multiple attacks of cholestasis over many years, no permanent liver damage has occurred. This case reaffirms the essentially benign nature of this disease.

Adolescent↗

High-dose rate and low-dose rate intracavitary therapy for carcinoma of the uterine cervix. Final results of Osaka University Hospital.

BACKGROUND: High-dose rate (HDR) intracavitary radiation therapy for carcinoma of the uterine cervix has gradually found wider acceptance. In 1983, the authors first presented the results of prospective randomized comparative study of HDR versus low-dose rate (LDR) therapy. In the current study, the final results of this study with a longer follow-up are presented. METHODS: From January 1975 through August 1983, 430 previously untreated patients with carcinoma of the uterine cervix in Stages I-III were treated with either HDR 60Co therapy or LDR 137Cs therapy at our department. HDR was administered to a total of 259 patients: 32 patients in Stage I, 80 in Stage II, and 147 in Stage III. LDR was administered to a total of 171 patients: 28 patients in Stage I, 61 in Stage II, and 82 in Stage III. RESULTS: The 5-year cause-specific survival rates of Stage I-III patients treated with HDR were 85%, 73%, and 53%, respectively. The corresponding figures for LDR were 93%, 78%, and 47%, respectively. There was no significant difference between these survival rates. Moderate-to-severe complications developed in 10% of the patients treated with HDR and 4% of those with LDR. This difference in the incidence of complications was statistically significant (P = 0.023). CONCLUSIONS: Treatment results in terms of cause-specific survival were equivalent for HDR and LDR treatment. However, the incidence of complications was higher for the HDR group, although within acceptable levels, than for the LDR group.

Actuarial Analysis↗

Radiosensitization by a new potent nucleoside analog: 1-(1',3',4'-trihydroxy-2'-butoxy)methyl-2-nitroimidazole(RP-343).

PURPOSE: A new hypoxic cell sensitizer has been synthesized; this is a 2-nitroimidazole nucleoside analog having erythritol as a sugar moiety at the N-1 position of the imidazole ring (RP-343). Its possibility as a potent hypoxic cell sensitizer was compared with those of RP-170 and etanidazole. METHODS AND MATERIALS: Radiosensitization was tested in two murine tumors, EMT6 using in vitro and in vivo-in vitro assays and SCCVII using growth delay and TCD50 assays. Pharmacokinetic study was performed in Balb/c mice bearing EMT6 tumors and in Beagle dogs. LD50 of each sensitizer was obtained with ICR mice. RESULTS: As might be expected from the almost identical electron affinities of the three sensitizers, they were equally effective against hypoxic EMT6 cells in vitro. While having the lowest partition coefficient (0.035), RP-343 exhibited almost equally effective distribution to tumors and sensitizing radiation activity. An intravenous (i.v.) injection of 100 mg/kg of RP-343, RP-170 and etanidazole showed an almost equal sensitizer enhancement ratio (SER) of about 1.4 to solid EMT6 tumor under in vivo-in vitro assay and a virtually equal SER of 1.33-1.44 to solid SCCVII tumor under both tumor growth delay assay and TCD50 assay. A great advantage of RP-343 over RP-170 and etanidazole is its very much lower toxicity; their LD50 in mice were > 6.0, 4.3 and 4.8 g/kg, respectively, on i.v. injection. The lower toxicity of RP-343 was supported by its lower concentrations in the brain; the RP-343 AUC for brain was 0.43 times that of RP-170. Three indices were selected to compare the three nitroimidazoles. SER at 5% LD50 doses of RP-343, RP-170 and etanidazole was 1.66, 1.59 and 1.56. At the same toxicity levels, RP-343 was found to have better sensitization of solid tumors over both etanidazole and RP-170. The maximum tumor concentration/AUC for brain (Cmax,tumor/AUCbrain) ratios for RP-343 and RP-170 were 9.62 and 3.98. CONCLUSIONS: This extremely high ratio of RP-343 could explain its lower toxicity than RP-170 or etanidazole. The therapeutic risk index defined as D1.5/LD50 (D1.5 is the sensitizer dose to obtain the SER of 1.5 in vivo) for RP-343, RP-170 and etanidazole were 0.022, 0.033 and 0.036, respectively. Especially, the effectively lower therapeutic risk index for RP-343 presents the possibility of clinical advantage over etanidazole.

Animals↗

Weak N activity of En(a-) human erythrocyte membranes.

The propositus's erythrocytes with phenotype En(a-), which was found for the first time in a Japanese family, reacted more weakly with anti-N serum than the ordinary phenotype N erythrocytes. The En(a-) erythrocytes lack the major membrane sialoglycoprotein (glycophorin A) as demonstrated by Bio-Gel 1.5m gel filtration from active sialoglycoproteins, which were isolated from En(a-) erythrocyte membranes by the method of lithium diiodosalicylate (LIS)-phenol extraction. It is suggested from observation via enzyme-linked immunosorbent assay (ELISA) that N activity is derived from the glycophorin B molecule on En(a-) erythrocyte membranes.

Antigens↗

Insulin-induced circular membrane ruffling on rat 1 cells expressing a high number of human insulin receptors: circular ruffles caused by rapid actin reorganization exhibit high density of insulin receptors and phosphotyrosines.

The early effects of insulin on morphological changes were examined using Rat1 cells expressing approximately one million human insulin receptors (Rat1HIR cells). Insulin transiently induced circular membrane ruffling on Rat1HIR cells. The circular ruffles were detected by phase microscopy as well as by fluorescence microscopy when actin was stained with rhodamine-conjugated phalloidin. The circular ruffles were also visualized by fluorescence microscopy when stained with either anti-insulin receptor monoclonal antibody, alpha IR-1, or anti-phosphotyrosine antibody, followed by fluorescein isothiocyanate-labeled second antibodies. Control Rat1 cells or Rat1HIR A/K1018 cells expressing kinase-defective insulin receptors did not show any circular ruffles when treated with insulin. These results suggest that the circular ruffles are formed by actin reorganization induced by insulin and that this process requires the protein-tyrosine kinase activity of the receptor. Detection of insulin receptors and phosphotyrosines in the circular ruffles suggests the possibility that the insulin receptors in the ruffles may be highly active and phosphorylating either the receptors themselves or proteins associated with the ruffles. These results are consistent with our previous in vitro observations that a large aggregate form of the purified insulin receptor is a highly active protein-tyrosine kinase.

Actin Cytoskeleton↗

Induction of discriminant function concerning postoperative local recurrence or distant metastasis in 589 patients with differentiated thyroid cancer.

For the purpose of predicting postoperative local recurrence and/or distant metastasis in differentiated thyroid cancer, a discriminant analysis was done. To assess the reliability of this method and the induced function, simulation was done by using random samples under various conditions. Simulation revealed that the results obtained by this method were relatively stable. The discriminant functions Z1 and Z2 were induced, which are required at many hospitals. If the ratio of recurrence is less than 1:8 in a hospital, function Z1 should be applied. If the ratio is 1:10, function Z2 should be applied. Z1 = -(sex x 2.104) + (age x 0.032) - (diameter of tumor x 0.033)-(site of tumor x 0.871) - (histology x 0.393) + 0.249 (discriminant boundary 0.451) Z2 = -(sex x 1.967) + (age x 0.018) + (diameter of tumor x 0.025) - (site of tumor x 0.646) + (histology x 0.014) - (local invasion x 0.840) - (lymph node metastasis x 0.009) + (operation x 0.364) - (lymph node dissection x 0.235) + 1.058 (discriminant boundary 0.400). In an internal check, sensitivity was 78%, specificity 64%; and false-negative rate 5%. In an external check, sensitivity was 68%, specificity 93%, and false-negative rate 9%. In the actual application to hospitals, sensitivity was 58% to 100%, specificity 47% to 63%, and false-negative rate 0% to 16%. In clinical usage, a high sensitivity and low false-negative rate are required. These results fulfilled this condition.

Adenocarcinoma, Follicular↗

Primary osteosarcoma of the skull--a case report and review of the literature.

Primary osteosarcoma of the skull (POS) in a young man with intracranial involvement is reported. After an initial transient remission by surgical intervention and chemotherapy, he began to deteriorate due to tumor recurrence and intracranial hemorrhage, and died 15 months following the time of diagnosis. The rarity and poor prognosis of POS are emphasized together with the review of the clinical and therapeutic aspects in the previously reported 98 cases in the literature.

Adult↗

Identification of alloantisera reacting with HLA-C blank (Cx52) using a mouse L-cell transfected with the HLA-Cw*1201 allele.

The HLA-C locus frequently has a serologically undefined "blank" (CwBL) specificity. A cDNA clone derived from the HLA-C gene with a blank specificity (Cx52) strongly associated with the most common haplotype in a Japanese population, A24-CwBL-B52-DR2-DQ6-DP9, has been recently cloned and sequenced in our laboratory and officially designated Cw*1201 as an allelic name, indicating that the inability to define the HLA-C antigen serologically in this haplotype is not due to an HLA-C antigen gene deletion or mutation, but to the absence of typing sera. In this paper, a mouse L-cell transfectant expressing this Cw*1201 gene product was constructed and employed for screening of alloantisera recognizing the HLA-C antigen with the Cw*1201 specificity. Two alloantisera against Cw*1201 were thus identified and characterized using HLA homozygous B-cell lines and local panel PBL cells, indicating that a transfectant expressing a single HLA provides an efficient screening system for collection of HLA-typing sera, especially reacting with serologically unclassifiable "blank" antigens.

Alleles↗

Effects of cigarette smoking on electrodermal orienting reflexes to stimulus change and stimulus significance.

Skin conductance responses (SCRs) evoked by novel, signal, and frequent tone stimuli were measured in 20 male heavy smokers and 10 male nonsmokers over two sessions. All smokers abstained from smoking for 12 hr prior to each session. Half of the smokers smoked a cigarette of their preferred brand prior to SCR measurement in the first session, whereas the remaining smokers smoked in the second session. Nonsmokers did not smoke. Results combined across the two sessions indicated that abstinence was associated with selective depression of SCRs to the novel tone. Separate analyses of results from each session revealed that, in the second session, SCRs to both novel and signal tones were depressed in abstinent smokers, partially replicating previous findings. By contrast, first session results showed no significant effects of smoking or abstinence. Results were interpreted in terms of nicotine's effects on nonspecific arousal, with some reservations.

Acoustic Stimulation↗

Electrical properties of the rabbit cortical collecting duct from obstructed and contralateral kidneys after unilateral ureteral obstruction.

Electrophysiological techniques were used to determine the electrical properties of the collecting duct (CD) cell in the isolated cortical collecting duct from obstructed (UUOOK) and contralateral (UUOCK) kidneys in rabbits 24 h after unilateral ureteral obstruction (UUO); results were compared with those from sham-operated kidneys. The lumen-negative transepithelial voltage and the basolateral membrane voltage (VB) were decreased in the UUOOK, and increased in the UUOCK. The transepithelial conductance (GT) was decreased in parallel with an increase in the fractional apical membrane resistance (fRA) and a decrease in apical membrane conductance in the UUOOK. By contrast, the GT was increased in parallel with increases in apical and basolateral membrane conductances in the UUOCK. The amiloride-sensitive changes in apical membrane voltage (VA), GT and fRA were lower in the UUOOK, but greater in the UUOCK. The changes in VA and GT upon raising the perfusate K+ concentration and upon addition of luminal Ba2+ were decreased in the UUOOK, and increased in the UUOCK. Addition of ouabain to the bath resulted in a smaller depolarization of VB in the UUOOK, but in a greater depolarization in the UUOCK. Upon lowering bath Cl-, the change in basolateral membrane electromotive force (delta EMF) was increased in the UUOOK, and decreased in the UUOCK. Reversely, upon raising bath K+, the delta EMF was decreased in the UUOOK, and increased in the UUOCK. We conclude: (a) the conductances of Na+ and K+ in the apical membrane, and active Na(+)-K+ pump activity and relative K+ conductance in the basolateral membrane are decreased in the UUOOK, and increased in the UUOCK; (b) the relative basolateral membrane Cl- conductance was increased in the UUOOK, and decreased in the UUOCK.

Amiloride↗

En(a-) phenotype in a Japanese blood donor.

The first Japanese En(a-) individual (T.N.) was found by screening red cells from 250,000 Japanese blood donors with monoclonal anti-Ena. His serum contained no atypical antibodies and his partial red cell phenotype was M-N-S+s-, although a trypsin- resistant N antigen was detected. His red cells were En(a-) and Wr(b-), as determined by various human and mouse monoclonal antibodies. The absence of glycophorin A (GPA) and the presence of apparently normal glycophorin B (GPB) were demonstrated by immunoblotting with antibodies to the extracellular and cytoplasmic domain of GPA and to epitopes common to GPA and GPB. Sialic acid levels of T.N.'s intact red cells were substantially lower than those of control MN cells. Serologic tests suggested that both of T.N.'s parents were heterozygous for a recessive GPA deficiency gene.

Journal Article↗

Small cell carcinoma of the esophagus with an esophago-mediastinal fistula successfully treated by chemoradiation therapy and intubation: a case report.

A case of esophageal small cell carcinoma with cervical node metastases and an esophago-mediastinal fistula was treated successfully by chemoradiotherapy. The fistula, after irradiation, was handled successfully by esophageal intubation, followed by infusional 5-fluorouracil and cisplatinum chemotherapy, resulting in the closure of the fistula. Two courses of concurrent chemoradiotherapy, followed by additional cisplatinum and etoposide chemotherapy, were administered. The tumor, including the cervical lymph node metastases, disappeared completely after the treatment.

Antineoplastic Combined Chemotherapy Protocols↗

[A case of food-dependent exercise-induced anaphylaxis associated with repeated episodes of syncope].

This report describes a patient with food-dependent exercise-induced anaphylaxis (FEA). A 25-year-old female has had three episodes of syncopal attack associated with urticaria in the past two years: the attacks have been developed by exercise after taking meals made of wheat flour. She has an allergic predisposition to metals. No abnormal findings were observed in the routine work up for syncope including, ECG, 24-hour Holter ECG, UCG, tilt table test, and EEG examinations. A provocative test for FEA was performed. It included food (sandwich) intake followed by exercise. The serum histamine concentration was elevated to a three times higher than the control value after the provocation. Accordingly, she was diagnosed as FEA and advised not to take wheat flour prior to physical exercise. No syncopal episode has been observed during the 16 months since the diagnosis.

Adult↗

The 90-kDa heat shock protein, HSP90, binds and protects casein kinase II from self-aggregation and enhances its kinase activity.

We found that a preparation of the 90-kDa heat shock protein, HSP90, purified to apparent homogeneity, contains a serine/threonine kinase which phosphorylates HSP90. The protein kinase was identified as casein kinase II (CKII) according to its properties. The protein kinase was separable from HSP90 by adsorption to heparin-Sepharose or phosphocellulose. CKII was coimmunoprecipitated with HSP90 by anti-HSP90 antibodies from cell extracts. Sucrose density gradient centrifugation analysis revealed that an addition of anti-HSP90 antibodies to cell extracts induces a shift of the sedimentation peak of CKII toward the bottom of a centrifuge tube. These results suggest that CKII is associated with HSP90 in cell lysates at low salt conditions. Furthermore, the CKII.HSP90 complex was reconstituted from purified HSP90-free CKII and CKII-free HSP90. In a buffer at low ionic strength, CKII forms large aggregates, but HSP90 dissociates the aggregates. Finally, we found that HSP90 activates CKII; an addition of HSP90 to CKII dramatically increased phosphorylation of exogenous substrates as well as the CKII beta subunit. Taken altogether, these observations suggest that CKII is structurally and functionally active when it forms a complex with HSP90.

Amino Acid Sequence↗

A case of combined primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia.

A rare case of primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia is described in a 49-year-old Japanese diabetic woman. Primary biliary cirrhosis was diagnosed by characteristic liver histology and positive serum mitochondrial antibody test. Ulcerative colitis was diagnosed by typical findings of barium enema and colonoscopy, negative fecal test for pathogens and compatible rectal histology. Chronic myelocytic leukemia was determined by representative hematologic findings and positive result for Ph1 chromosome. This is the first case with combination of primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia.

Colitis, Ulcerative↗

Heavy chain binding protein (BiP/GRP78) and endoplasmin are exported from the endoplasmic reticulum in rat exocrine pancreatic cells, similar to protein disulfide-isomerase.

Previously we found that in rat exocrine pancreatic cells, protein disulfide-isomerase (PDI), one of the major resident proteins in the lumen of the endoplasmic reticulum (ER) of many cells, is localized not only in the ER but also in the Golgi apparatus, secretory granules, plasma membranes, and even in the glandular lumens, despite possessing the ER retention signal KDEL (Lys-Asp-Glu-Leu) at the carboxyl terminus. In this report, we examined whether other ER luminal proteins bearing the KDEL signal at their C-termini, such as BiP/GRP78 and endoplasmin/GRP94 are also exported from the ER. We prepared two kinds of affinity-purified polyclonal antibodies; one against a synthetic peptide with 12 amino acids which is identical to the carboxyl terminus of BiP and another against purified endoplasmin. Immunoblot analysis using these two antibodies showed that BiP and endoplasmin exist in both the plasma membrane and the microsomal fractions, similar to the intracellular distribution of PDI in rat exocrine pancreas. The ratios of the amount of the three proteins in the two fractions, however, were variable, suggesting that the KDEL-bearing proteins such as PDI, BiP, and endoplasmin are exported from the ER with different efficiencies. Postembedding protein A-immunogold electron microscopy revealed that endoplasmin was exported from the ER and secreted to the extracellular space. The secretion of PDI in rat pancreatic lobules was inhibited by Brefeldin A (BFA) and by guanidino acid esters (FOY-305), which are known to be the inhibitors of the intracellular transport. Taken together with the previous immunogold electron microscopic analyses by Akagi et al. (1988), it is strongly suggested that in rat exocrine pancreatic cells PDI and the other KDEL-bearing proteins found in the extracellular space were not artificially released by cell damage during incubation but were secreted via the normal secretory pathway.

Amino Acid Sequence↗