Biomedical subjects

M Shimoyama

Publications and source records attributed to M Shimoyama.

At least 73 records · Page 4Linked to original sources

PubMed1998

Japan Clinical Oncology Group (JCOG).

The Japan Clinical Oncology Group (JCOG) is a cooperative oncology group with the aims of conducting, developing, coordinating and stimulating clinical research in Japan on the treatment of cancer and related problems. The purpose of JCOG is to establish and improve the standard of cancer treatment, mainly in solid cancer, through the testing of new therapeutic regimens or combined modalities, using drugs that are newly-approved or already commercially available. Research sponsored by JCOG is accomplished mainly through the execution of large, prospective, randomized, multicenter, clinical trials. In this way, JCOG facilitates the passage of new clinical trial discoveries into state-of-the-art treatment.

Clinical Trials as Topic↗

PubMed1998

Visual function and gene analysis in a family with Oguchi's disease.

A family with 1 case of retinitis pigmentosa (III-1) and 2 cases of Oguchi's disease (III-2, 3) was examined in terms of electrophysiology as well as molecular biology. The proband (III-3), a 42-year-old female, and 2 older brothers (III-1, 2, aged 52 and 45 years) and 2 unaffected members in the same family participated in this study. Corrected visual acuities of the individuals with Oguchi's disease (III-2, 3) were 1.2. On funduscopy, blood vessels stood out in relief against a metallic-appearing background and a Mizuo-Nakamura phenomenon was evident. Full-field electroretinograms (ERGs) recorded from the proband were indicative of rod dystrophy, but results of other electrophysiological examinations (multifocal ERG, pattern ERG and visual-evoked cortical potential recordings) were within normal limits. Patient III-1 had corrected visual acuities of RE 20 cm/m.m. and LE 30 cm/n.d., severe chorioretinal atrophy in both fundi, and full-field ERG revealed rod-cone dystrophy. Mutation of the arrestin gene (1147de1A) was detected in all 3 patients. Visual function in each patient coincides with that of retinitis pigmentosa or Oguchi's disease, respectively.

Adult↗

PubMed1998

Hematuria in patients with renal hypouricemia.

The characteristics of urate metabolism in renal hypouricemic patients with hematuria were studied to clarify the risk factors for hematuria in patients with renal hypouricemia. In 16 Japanese patients with isolated renal hypouricemia, urate metabolism was measured using the urate clearance study and the subtype of renal hypouricemia [defective presecretory reabsorption (Pre), defective postsecretory reabsorption (Post), enhanced tubular secretion (Secretion) and defective presecretory and postsecretory reabsorption (Pre&Post)] were determined by the pharmacological tests. Hematuria was seen in 7 out of the 16 patients (44%), all of whom were females (58%). Serum urate and urinary urate concentrations were significantly higher in the group with hematuria (Sur = 1.76 +/- 0.31 mg/dl and Uur/Ucr = 0.75 +/- 0.12: p<0.05) than in the group without hematuria (Sur = 1.44 +/- 0.46 mg/dl and Uur/Ucr = 0.56 +/- 0.04), although there was no difference in the urate excretion rate between the two groups. Hematuria was more likely to be accompanied by Post (75%) and Secretion (75%), which showed significantly higher urinary urate concentration (Uur/Ucr = 0.75 +/- 0.1 and 0.69 +/- 0.13, respectively) than by Pre (25%) and Pre&Post (0%), which showed lower urinary urate concentration (0.61 +/- 0.06 and 0.62 +/- 0.05, respectively). The risk factors for hematuria in patients with renal hypouricemia are the elevation of urinary urate concentration and the subtypes of Post and Secretion.

Adult↗

PubMed1998

Excess urate excretion correlates with severely acidic urine in patients with renal hypouricemia.

We evaluated the renal handling of urate in 12 Japanese renal hypouricemia patients, and studied the relationship between the renal handling of urate and the urinary pH. The patients were classified into the 4 subtypes of renal hypouricemia: (defective presecretory reabsorption (Pre), defective postsecretory reabsorption (Post), enhanced tubular secretion (Secretion), and defective presecretory and postsecretory reabsorption (Pre&Post) as based on a pharmacological test. Seven patients showed acid urine with a urinary pH of less than 5.9, although this was not accompanied by any abnormality of blood pH, partial pressure of carbon dioxide (PaCO2), or blood HCO3-. The urinary pH in the morning significantly correlated with the ratio of urate clearance to creatinine clearance in the morning, whereas the urinary urate concentration in the morning did not correlate with the urinary pH in the morning. In the Pre&Post patients, the urate excretion was higher and the urinary pH was more acidic compared to the other subtypes. The administration of K+-, Na+-citrate significantly alkalized the urinary pH in the patients with renal hypouricemia. These results suggest that the acidic urine was significantly related to the Pre&Post subtype of renal hypouricemia with the higher urate excretion, and that this subtype might be a risk factor for complications in renal hypouricemia. The alkalization of urine might be a useful treatment for the complication of renal hypouricemia.

Adult↗

PubMed1998

Reoxygenation injury in a cultured corneal epithelial cell line protected by the uptake of lactoferrin.

PURPOSE: To investigate whether reoxygenation after extended hypoxia causes cellular damage in cultured corneal epithelial cells and to demonstrate the protective effects of lactoferrin. METHODS: Immortalized human corneal epithelial cells (T-HCECs) were cultured to confluence in 96-well culture plates, subjected to stringent hypoxia (1% O2, 5% CO2, 94% N2 at 37 degrees C) for 24 hours, and returned to normoxic conditions (5% CO2, 95% air at 37 degrees C). Cell viability was observed by 1 microM propidium iodide staining 0, 2, 4, and 6 hours after reoxygenation. Inhibition studies were performed after 2 hours' reoxygenation, using 2 mM iron chelator desferrioxamine and 0.2 mg/ml lactoferrin. Confocal immunocytochemistry for human lactoferrin and western blot analysis for lactoferrin-induced ferritin were performed in cultured T-HCECs to demonstrate the internalization of lactoferrin after application. RESULTS: After 2 hours, reoxygenation of T-HCECs after hypoxia produced an increase in cell death that was significantly greater than that observed in normoxic control cells or in cells subjected to hypoxia for the same time span without reoxygenation. The addition of desferrioxamine and lactoferrin at the time of reoxygenation significantly attenuated cellular damage. Confocal immunocytochemistry revealed that lactoferrin is taken into the cytoplasm of T-HCECs as early as 30 minutes after application. This was also demonstrated in western blot analysis by the upregulation of intracellular ferritin at 18 hours by the addition of iron-bound lactoferrin but not by iron-free lactoferrin. CONCLUSION: Reoxygenation is responsible for increased cellular damage after extensive hypoxia, which is attenuated by chelators of free iron in the cytosol, including the major tear protein lactoferrin.

Blotting, Western↗

PubMed1998

[The management of Hodgkin's disease with chemotherapy or combined modality treatment].

Systemic polychemotherapy and local radiation are two well-established treatments for Hodgkin's disease. With the use of modern techniques, the great majority of patients with pathologic stage I-II Hodgkin's disease can be cured with irradiation alone. Since the invention of the MOPP and ABVD schemes, polychemotherapy has become indispensable for the treatment of advanced-stage Hodgkin's disease. The role of radiotherapy in combination with chemotherapy is limited to specific indications. ABVD therapy is as effective as MOPP alternating with ABVD, and both are superior to MOPP alone in the treatment of advanced Hodgkin's disease. MOPP/ABVD hybrid chemotherapy was significantly more effective than sequential MOPP-ABVD in 8-year failure-free survival and overall survival. The patients with advanced-stage Hodgkin's disease who did not achieve a complete remission from their initial treatment with combination chemotherapy have a dismal prognosis. Those whose initial remissions had lasted longer than 12 months had a very high probability of obtaining a second complete remission when re-treated with MOPP or ABVD, but those whose remission lasted less than 12 months fared less well with any conventional-dose chemotherapy. High-dose chemotherapy and radiotherapy with autologous hemopoietic stem cell transfusion are superior in the treatment of those whose disease is refractory or resistant to the initial therapy.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1997

ADP-ribosylation of tuftsin suppresses its receptor-binding capacity and phagocytosis-stimulating activity to murine peritoneal macrophages.

Arginine-specific ADP-ribosyltransferase present in granules of chicken polymorphonuclear leukocytes (so-called heterophils) is released into the extracellular space by stimulus of calcium ionophore A23187 or opsonized zymosan [Terashima et al. (1996) J. Biochem. 120, 1209-1215]. In the present work, we examined extracellular targets of the released transferase and identified tuftsin, a phagocytosis-stimulating tetrapeptide derived from leukokinin, as a preferential substrate of the enzyme in chicken plasma. Specific binding of FITC-tuftsin to murine peritoneal macrophages, observed under a fluorescent microscope, was impaired by ADP-ribosylation of the labelled peptide. Phagocytic assay analyzed by flow cytometry revealed that ADP-ribosylation of tuftsin decreased its phagocytosis-stimulating activity towards the macrophages. Thus, the ADP-ribosylation of tuftsin apparently decreases its biological activity and ADP-ribosylation may possibly be involved in inflammatory processes through alterations in tuftsin activity.

Adenosine Diphosphate Ribose↗

PubMed1997

Expression of a kinase-defective Eph-like receptor in the normal human brain.

We have identified a human Eph-family protein, HEP, gene located in human chromosomal region 7q33-->q35. The deduced amino acid sequence shared primary structural properties of Eph-family receptor tyrosine kinases. However, six invariant amino acids such as a lysine in the ATP-binding site and an aspartic acid in the phosphotransfer site of a conserved catalytic domain were substituted with other amino acid residues in HEP. Thus, no intrinsic tyrosine kinase activity was detectable in the catalytic domain expressed in CHO-K1 cell transfectants. Although most kinase-defective mutants of growth factor receptors have been reported as pathogenic receptors, its transcript was abundantly expressed in normal human adult tissues. A 135-kDa HEP protein was expressed in the human brain as much as in CHO-K1 cells transfected with a HEP cDNA expression vector. HEP is the first description of a kinase-defective Eph-family protein expressed abundantly in normal human tissues.

Adenosine Triphosphate↗

PubMed1997

Spinal gabapentin is antinociceptive in the rat formalin test.

Gabapentin is a novel anticonvulsant that may be of value for the relief of clinical pain. To determine whether gabapentin is antinociceptive after spinal administration, the drug was given via an intrathecal catheter in doses from 6 to 200 micrograms/rat 10 min prior to intraplantar formalin. Five percent formalin injected subcutaneously in the right hind paw produced a biphasic reaction consisting of flinching and licking behaviors (phase 1, 0-10 min; phase 2, 10-60 min). Gabapentin dose-dependently reduced the numbers of flinches and the duration of licking during phase 2 of the formalin test. The highest dose of gabapentin (200 micrograms/rat) did not affect the tail-flick response. These results demonstrate that spinal gabapentin is antinociceptive in the formalin test.

Acetates↗

PubMed1997

Immunohistochemical localization of ADP-ribosylarginine hydrolase in rodent CNS.

Polyclonal antibodies were generated against ADP-ribosylarginine hydrolase (AAH), using recombinant fusion protein of rat AAH and glutathione-S-transferase as a immunogen, and affinity-purified. Western blotting showed that the antibodies recognized in mouse brain homogenate a single protein with a molecular mass of 38 kDa, the expected size for mouse AAH. An analysis using the antibodies revealed that heavy labelings were apparent in various brain regions. In the cerebral cortex, pyramidal cells in layers III and V were the most heavily labeled. In the hippocampal formation, labeling was present on the pyramidal neurons and granule cells. The most heavily immunostained cell type was the pyramidal neuron of CA3. In the cerebellum, Purkinje cells were the most heavily labeled. Less intense staining was present over the granule cells. In the basal ganglia, neurons in the caudate nucleus and large multipolar cells in the amygdaloid complex were immunoreactive. Heavy labeling was seen in many midbrain and brainstem nuclei. Neurons in the habenula and ependymal cells were stained heavily. On Western blot analysis of rat cerebrospinal fluid (CSF), the anti-AAH antibodies recognized a protein with a molecular mass of 38 kDa. This is apparently the first evidence of a widespread but distinctive distribution of AAH in neurons of mouse brain and the presence of extracellular AAH in rat CSF.

Animals↗

PubMed1997

Molecular cloning and characterization of arginine-specific ADP-ribosyltransferases from chicken bone marrow cells.

Among a number of tissues and peripheral blood cells in chicken, leukocytes, bone marrow cells, liver and spleen showed high ADP-ribosyltransferase activity, with leukocytes having the highest. Density gradient centrifugation of the leukocytes revealed that the leukocyte ADP-ribosyltransferase originates in the polymorphonuclear cells, so called heterophils. Subcellular distribution of the cells showed the localization of the enzyme in the granule fraction. Based on the obtained amino acid sequences of arginine-specific ADP-ribosyltransferase purified from chicken peripheral heterophils, two arginine-specific ADP-ribosyltransferase cDNAs (designated AT1 and AT2) were obtained from chicken bone marrow cells. Each cDNA encodes a different peptide of 312 amino acid residues. Homology of the deduced amino acid sequences between AT1 and AT2 was 78.3%. Arginine-specific ADP-ribosyltransferase activity was detected in culture medium of COS 7 cells transiently transfected with AT1 cDNA, while activity from the cells transfected with AT2 cDNA was found in both culture medium and cell lysate. AT1 transferase required 2-mercaptoethanol (MSH) for the activity and in the presence of NaCl, the activity was inhibited while the AT2 enzyme was activated by either agent. Highly conserved regions were observed among the deduced amino acid sequences of AT1, AT2, chicken erythroblast and rabbit and human skeletal muscle ADP-ribosyltransferases, and rodent T-cell surface antigen RT6. Two forms of the transferase with much the same properties as AT1 and AT2 proteins, regarding the effect of NaCl and MSH, were detected in bone marrow cells. Based on these results it seems that AT1 and AT2 cDNAs encode the two forms of arginine-specific ADP-ribosyltransferase detected in chicken bone marrow cells.

ADP Ribose Transferases↗

PubMed1997

A newly identified glycosylphosphatidylinositol-anchored arginine-specific ADP-ribosyltransferase in chicken spleen.

An arginine-specific ADP-ribosyltransferase activity was detected in chicken spleen membrane fraction using a capillary electrophoresis assay and the activity was extracted by phosphatidylinositol-specific phospholipase C but not by 1 M NaCl or 1% Triton X-100. The enzyme protein was purified from chicken spleen membrane fraction to apparent homogeneity with a six-step method containing phosphatidylinositol-specific phospholipase C treatment, ammonium sulfate precipitation and conventional column chromatographies. Apparent molecular mass of the purified enzyme estimated with SDS/PAGE was 44 kDa. N-glycanase treatment of the enzyme reduced the apparent molecular size on SDS/PAGE. The enzyme was recognized by anti-cross reacting determinant antibodies. Partial amino acid sequence of the purified enzyme protein showed high homologies with primary structures of previously reported chicken arginine-specific ADP-ribosyltransferases.

ADP Ribose Transferases↗

PubMed1997

Oral ketamine produces a dose-dependent CNS depression in the rat.

The oral to parenteral potency of ketamine to produce central nervous system (CNS) depression was estimated in rats using a behavioral scale. As a function of dose, ketamine produces CNS depression that ranges from ataxia to anesthesia by either route of administration. The oral ED50 value for ketamine was 120 mg/kg (82.2-159.2, 95% CI) while the intravenous ED50 value was 3.7 mg/kg (2.4-5.1, 95% CI). Oral ketamine produces CNS effects comparable to intravenous ketamine, although the drug is approximately 32 fold less potent by the oral route.

Administration, Oral↗

PubMed1997

GTP-dependent modification of a 21-kDa substrate with NAD+ in bovine brain soluble fraction is not ADP-ribosylation of small G-protein but tailing of tRNA.

Labeling of 21-kDa material was observed when bovine brain soluble fraction was incubated with [adenylate-32P]NAD+ in the presence of GTP. The 21-kDa substrate, slightly smaller than C3 substrate in size, was labeled even without C3 exoenzyme. GTP could be replaced by nucleoside triphosphates other than ATP while ATP inhibited the GTP-induced labeling of 21-kDa substrate. After incubation of the soluble fraction with [adenylate-32P]NAD+ in the presence of GTP, [32P]ADP and [32P]ATP were detected in addition to [32P]AMP and [32P]ADP-ribose while only the last two nucleotides were observed without GTP. The 21-kDa substrate was labeled with [alpha-32P]ATP even in the absence of GTP, suggesting adenylylation rather than ADP-ribosylation. The labeled 21-kDa substrate, was extractable by phenol, disappeared with RNase treatment but not with tryptic digestion. Alkaline treatment of the phenol extract yielded an equal mixture of 3'-[32P]CMP and 2'-[32P]CMP. From these results we concluded that the 21-kDa labeling is a result of tRNA tailing with [alpha-32P]ATP generated from the [32P]AMP moiety of [adenylate-32P]NAD+. Results from reconstitution experiments using enzymes and tRNA purified from bovine brain soluble fraction, which are involved in this pathway, confirmed our conclusion.

ADP Ribose Transferases↗

PubMed1997

Gabapentin enhances the antinociceptive effects of spinal morphine in the rat tail-flick test.

The antinociceptive effects of the combination of spinal morphine and gabapentin were evaluated in the tail-flick test in rats. The intrathecal coadministration of a subantinociceptive dose of morphine at 0.2 microgram and gabapentin at 300 micrograms produced significant antinociception. Pretreatment with spinal gabapentin at 300 micrograms shifted the dose-response curve of spinal morphine to the left with a decrease in morphine ED50 value from 1.06 micrograms to 0.34 microgram. The antinociceptive effects produced by the combination of a subantinociceptive dose of morphine and gabapentin were reversed by spinal naloxone at 30 micrograms but were not reversed by spinal bicuculline at 0.3 microgram. Furthermore, the concurrent administration of spinal naloxone at 30 micrograms with the combination of morphine and gabapentin blocked antinociception, while the concurrent administration of spinal bicuculline at 0.3 microgram failed to prevent antinociception. These results indicate that the combination of spinal gabapentin and morphine produces an enhancement of antinociception that appears to involve the spinal mu opioid receptors. Furthermore, repeated administration of gabapentin for 3 days did not affect the enhancing effect of gabapentin on the antinociceptive effect of morphine, indicating that tolerance did not develop to gabapentin's ability to enhance morphine antinociception.

Acetates↗

PubMed1997

Prognostic factors and prognostic staging system for small cell lung cancer.

This study was performed to assess the prognostic factors and the predictors of long-term (3-year) survival in patients with small cell carcinoma of the lung, accrued in one randomized trial, and to define patient subgroups showing significantly different survivals using recursive partitioning and amalgamation analysis. A total of 300 patients with small cell carcinoma of the lung were entered into a randomized study comparing cyclophosphamide, adriamycin and vincristine (CAV), cisplatin and etoposide (PE) and alternating treatments of CAV and PE. Of these, 286 patients were analysed for the present study of prognostic factors. Multivariate analysis showed that poor performance status (2-3) (P = 0.0001), extensive disease (P = 0.0015) and abnormally elevated serum lactate dehydrogenase (P = 0.0001) and alkaline phosphatase (P = 0.0013) were independently adverse pretreatment prognostic factors. Of limited disease patients, performance status (P = 0.029) and white blood cell count (P = 0.044) had a significant influence on the probability of 3-year disease-free survival. Using recursive partitioning and amalgamation analysis, three classes of similar prognosis were identified: the most favorable class was defined by knowledge of lactate dehydrogenase (normal), performance status (0-1) and serum sodium levels (normal) with median survival time of 16.0 months, and the class with the poorest prognosis was defined by knowledge of lactate dehydrogenase (elevated) and performance status (2-3) (median survival time 6.6 months). The intermediate class had a median survival time of 9.4 months. In conclusion, this subclassification system will be used for the design, implementation and interpretation of clinical studies as well as decision-making in individual patients.

Adult↗

PubMed1997

A phase II study of high-dose epirubicin (EPI) plus cyclophosphamide (CPA) with G-CSF for breast cancer patients with visceral metastases or hormone-independent tumors: a trial of the Japan Clinical Oncology Group.

To evaluate the efficacy and toxicity of high-dose epirubicin (EPI) plus cyclophosphamide (CPA) therapy, a phase II study of EPI, 130 mg/m2, plus CPA, 1000 mg/m2, with G-CSF every 3 weeks was carried out for 51 advanced or recurrent breast cancer patients by the Japan Clinical Oncology Group (JCOG). Fifty out of the 51 patients who were eligible for our criteria were treated with this regimen as first-line chemotherapy for visceral metastases or hormone-independent tumors. In this trial, 203 cycles were administered with an average of four cycles per patients. In 50 patients who were evaluable for response, there were 7 complete (CR) and 25 partial responses (PR) with an overall response rate of 64% (95% confidence interval, 50.1-75.9%). Symptomatic and hematological acute toxicity more than grade 3 occurred frequently; however, no treatment-related death occurred. The incidence of toxicities (> or = grade 3) was as follows: leukopenia 98%, thrombocytopenia 42%, nausea/vomiting 56% and hair loss 12%. In each cycle, daily administration of 2 micrograms/kg G-CSF (granulocyte-colony stimulating factor) was given on days 2-15 subcutaneously. The incidence of cardiotoxicity was low. Arrhythmia (< or = grade 2) was observed in 8% and a slight decrease of ejection fraction index (< or = grade 2) was observed in 2% in this trial. The median follow-up period for patients was 37.2 (24.6-51.5) months and the median survival period was 17.4 months. These data indicate that high-dose EPI + CPA combination chemotherapy was effective and well tolerated for breast cancer patients with visceral metastases or hormone-independent tumors. A randomized trial of high-dose EPI vs conventional chemotherapy is required to ascertain the usefulness of this regimen.

Adult↗

PubMed1997

Nitric oxide-induced modification of glyceraldehyde-3-phosphate dehydrogenase with NAD+ is not ADP-ribosylation.

One biological effect of nitric oxide (NO) has been believed to be exerted through induction of the ADP-ribosyltransferase activity of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Though this notion is based on the finding that NO increases the auto-ADP-ribosylation of GAPDH, controversial data have also been reported. To determine whether or not NO really activates ADP-ribosylation, we re-examined the NO-induced modification of GAPDH with NAD+. GAPDH was modified equally with [adenosine-14C]NAD+ and [carbonyl-14C]NAD+, indicating that the glycoside bond of NAD+ between ADP-ribose and nicotinamide is intact. The release of nicotinamide from NAD+ was not evident during incubation of GAPDH with [carbonyl-14C]NAD+. Thus, the modification of GAPDH is apparently not ADP-ribosylation. In addition, we found that basal and glyceraldehyde-3-phosphate-induced modifications of GAPDH, both of which have also been explained as ADP-ribosylation, were not ADP-ribosylation, and that the modification of GAPDH in the absence and presence of NO or GA3P was distinct in the dithiothreitol effect or resistance to HgCl2.

Adenosine Diphosphate Ribose↗