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Biomedical subjects

M Miyake

Publications and source records attributed to M Miyake.

At least 19 recordsLinked to original sources

MRP-1/CD9 gene transduction regulates the actin cytoskeleton through the downregulation of WAVE2.

Motility-related protein-1 (MRP-1/CD9) is involved in cell motility. We studied the change in the actin cytoskeleton, and the expression of actin-related protein (Arp) 2 and Arp3 and the Wiskott-Aldrich syndrome protein (WASP) family according to MRP-1/CD9 gene transduction into HT1080 cells. The frequency of cells with lamellipodia was significantly lower in MRP-1/CD9-transfected HT1080 cells than in control HT1080 cells (P<0.0001). MRP-1/CD9 gene transduction affected the subcellular localization of Arp2 and Arp3 proteins. Furthermore, MRP-1/CD9 gene transduction induced a downregulation of WAVE2 expression (P<0.0001). However, no difference was observed in the expression of Arp2, Arp3 or other WASPs. A neutralizing anti-MRP-1/CD9 monoclonal antibody inhibited downregulation of WAVE2 in MRP-1/CD9-transfected HT1080 cells (P<0.0001), and reversed the morphological effects of MRP-1/CD9 gene transduction. Furthermore, downregulation of WAVE2 by transfection of WAVE2-specific small interfering RNA (siRNA) mimicked the morphological effects of MRP-1/CD9 gene transduction and suppressed cell motility. However, transfection of each siRNA for Wnt1, Wnt2b1 or Wnt5a did not affect WAVE2 expression. Transfection of WAVE2-specific siRNA also did not affect expressions of these Wnts. These results indicate that MRP-1/CD9 regulates the actin cytoskeleton by downregulating of the WAVE2, through the Wnt-independent signal pathway.

Actin-Related Protein 2↗

Portal venous tumor thrombus associated with hepatic metastasis of renal cell carcinoma: case report.

We report a case of liver metastasis of renal cell carcinoma with portal venous tumor thrombus. Abdominal computed tomographic images showed a large hepatic mass that enhanced slightly during arterial phase. Multiple hypoattenuating lesions were seen in the intrahepatic portal venous branches and were traced directly from the mass. The histologic specimen confirmed metastatic liver tumor of renal cell carcinoma with portal venous tumor thrombus.

Adult↗

Exogenous hyaluronic acid enhances porcine parthenogenetic embryo development in vitro possibly mediated by CD44.

Exogenous hyaluronic acid (HA) has been reported to improve early embryo development in vitro in pigs and cows. Although early embryo development in vitro is improved by exogenous HA, the mechanism mediating the action of HA is not clearly defined. In the present study, two possible HA actions on early embryo development were proposed to understand interactions between HA and the embryos using porcine parthenotes. We hypothesized that improvement of early embryo development mediated by HA would be caused by embryo-derived growth factors due to the high molecular weight of HA or cellular response through its receptor (CD44). We examined the effects of HA molecular weight on parthenogenetic embryo development, permeability of HA into the zona pellucida, expression of CD44 in porcine parthenotes at various stages, and blocking interactions between HA and CD44 by monoclonal anti-CD44 antibody (mCD44Ab). As a result, although development of porcine parthenotes to the blastocyst stage was significantly enhanced by exogenous HA with various molecular weights, there was no difference in blastocyst formation among the various molecular weights (P < 0.05). Immunofluorescence revealed that exogenous HA was accessible to CD44 through the zona pellucida, irrespective of the oocyte activation and that CD44 was also expressed in both oocytes and parthenotes at all developmental stages. In addition, development of parthenotes was partially blocked by mCD44Ab. In conclusion, we demonstrated that exogenous HA enhanced development of porcine parthenotes in vitro. This improvement mediated by exogenous HA on parthenogenetic embryo development was possibly caused by cellular response via CD44.

Animals↗

Effects of spaceflight on postnatal development of arterial baroreceptor reflex in rats.

AIM: It has been reported that spaceflight attenuates the arterial baroreceptor reflex. As this reflex function changes dramatically during postnatal development, we hypothesized that space flight depresses the developmental changes of the reflex system. To test this hypothesis, we evaluated the baroreceptor reflex function in rats, which were exposed to a microgravity environment on a space shuttle 9-25 days after birth. METHODS: Baroreceptor reflex sensitivity and the afferent sensitivity were evaluated by measuring heart rate (HR) and aortic nerve activity (ANA) changes in response to an increase in mean arterial pressure (MBP) derived by phenylephrine injection (20-50 microg kg(-1)) under urethane-anaesthesia. RESULTS: Baroreceptor reflex sensitivity (% change of HR/% change of MBP) was lower in the flight group (FLT: -0.19 +/- 0.04, n = 4) than either the asynchronous ground control group (AGC: -0.47 +/- 0.06, n = 6, P < 0.01) or the vivarium group (VIV: -0.41 +/- 0.07, n = 6, P < 0.05). This was similar to the differences of the afferent sensitivity (% change of ANA/% change of MBP) between FLT (2.07 +/- 0.30) and the control groups (AGC: 2.71 +/- 0.22, n.s.; VIV: 3.00 +/- 0.32, P < 0.05). At the end of 30 days of recovery under normal gravity conditions, however, there were no significant group differences in these parameters. conclusion: These results suggest that the space environment attenuates the postnatal development of the arterial baroreceptor reflex function in rats, which may be partially because of a depression of the postnatal development of the baroreceptor afferents. These functional alterations, however, recover to their normal level on re-exposure to the Earth's gravity.

Animals↗

Spaceflight alters the fiber composition of the aortic nerve in the developing rat.

Hydrostatic pressure gradients due to the gravitational force in blood vessels disappear under conditions of microgravity during spaceflight, and the ability of the baroreceptor reflex to control arterial pressure and blood distribution may be altered. We hypothesized, on the basis of the results obtained in our previous experiments using the head-down tilt method in rats and rabbits, that the range of increase in arterial pressure caused by animal behavior narrows under conditions of microgravity, affecting the development of high-threshold unmyelinated fibers in the rat aortic nerve which sends signals from baroreceptors located in the aortic wall to the reflex center. We verified this hypothesis using 9-day-old rat neonates housed with their dams for 16 days on the space shuttle Columbia in outer space (STS-90, Neurolab Mission). Age-matched neonatal rats with the dams remained on the ground as controls. After breeding was carried out in the three experimental groups (FLT, spaceflight; AGC, asynchronous ground control; VIV, vivarium ground control), specimens of the 25-day-old rats were excised and five left aortic nerves in each group were examined by electron microscopy. The number of aortic unmyelinated fibers was significantly less in the FLT group than in each ground control (mean+/-S.D.; 139+/-37 in the FLT, 207+/-36 in the AGC, 283+/-121 in the VIV; P<0.05), which may be related to the weakness of the baroreceptor reflex under conditions of microgravity in space. This result may contribute to understanding of the several cardiovascular issues which occur under microgravity and after reexposure to gravity in human.

Analysis of Variance↗

Comparative analysis and development of microsatellite markers on swine (Sus scrofa) chromosome 1qter.

Several quantitative trait loci (QTL) have been detected on SSC1qter (Sus scrofa chromosome 1qter), including QTL for the number of vertebrae, as reported in our previous study. To provide the tools for analysis of QTLs on SSC1qter, we constructed a comparative map of swine and human. In addition, we identified 26 swine STSs and mapped 16 of them on SSC1qter using the INRA - University of Minnesota porcine radiation hybrid (IMpRH) panel. We screened a BAC library using these swine STSs and developed 35 new polymorphic microsatellite markers from the BAC clones, of which 26 were informative in our reference family. We also mapped nine microsatellite markers we had isolated previously. Consequently a total of 44 new polymorphic microsatellite markers were located within a 60-cM region of SSC1qter, spanning from SW1092 to the telomere.

Animals↗

[Multimodality therapy for diffuse malignant pleural mesothelioma].

Despite the rising incidence of diffuse malignant pleural mesothelioma (MPM), there is still no standard treatment for this disease, and the prognosis for patients remains poor. Recently, long-term survival has been reported when multimodality therapy is used, combining extrapleural pneumonectomy with perioperative chemotherapy and/or radiotherapy in highly selected patients. We report a case of a patient who presented with MPM, accompanied by a large malignant pleural effusion and pneumothorax, who was successfully treated with combination therapy. After being diagnosed with epithelial type MPM using thoracoscopic surgery, the patient underwent extrapleural pneumonectomy. Examination of the surgical specimen revealed invasion of the chest wall muscle and fat, as well as several positive mediastinal lymph nodes. The patient received 2 courses of postoperative chemotherapy using cisplatin and gemcitabine. He is currently alive and has been disease-free for 2 years.

Aged↗

Clinical significance of transmembrane 4 superfamily in colon cancer.

Cell motility is an important cellular function closely related to the processes of tumour progression and metastasis. Several members of transmembrane 4 superfamily (TM4SF) have been reported to be associated with cell motility and metastatic potential of solid tumour. The aim of this study is to clarify the clinical significance of the member of TM4SF (MRP-1/CD9, KAI1/CD82 and CD151) in human colon cancer. We studied 146 colon cancer patients who underwent curative surgery and studied the expression of MRP-1/CD9, KAI1/CD82 and CD151 using reverse transcriptase - polymerase chain reaction and immunohistochemistry. We found that 64 patients (43.8%) had MRP-1/CD9-positive tumours and that the overall survival rate of patients with MRP-1/CD9-positive tumours was much higher than that of patients with MRP-1/CD9-negative tumours (89.8 vs 50.8%, P<0.001). In contrast, 63 patients (43.2%) had KAI1/CD82-positive tumours and the overall survival rate of patients with KAI1/CD82-positive tumours was also higher than that of patients with KAI1/CD82-negative tumours (84.8 vs 54.9%, P=0.002). On the other hand, positive CD151 expression had a bad effect on the overall survival rate of patients with colon cancer (61.2 vs 74.9%, P=0.022). In a multivariate analysis, MRP-1/CD9 status was a good indicator of the overall survival (P=0.007). We have shown that the reduction of MRP-1/CD9 and KAI1/CD82 expression, and the increasing CD151 expression are indicators for a poor prognosis in patients with colon cancer. This is a first report describing about the relation between CD151 and colon cancer.

Aged↗

Stage-specific effects of the osmolarity of a culture medium on the development of parthenogenetic diploids in the pig.

The objective of this study was to investigate the effects of osmolarity of culture media on the development of porcine parthenogenetic diploids. Oocyte-cumulus-granulosa cell complexes were collected from ovaries and then in vitro-cultured for 48 h. The mature oocytes were subjected to a single electro-stimulation (El-St; 100 micros, 1500 V/cm), treated with 5.0 microg/ml Cytochalasin B for 4h and then cultured under various conditions as described below. In Experiment 1, the diploids were cultured for 168 h after El-St in modified Whitten's medium with 256 mOsmol (mWM256), mKRB with 309 mOsmol, and mWM with 309 mOsmol (mWM309), in which the osmolarity was adjusted by addition of NaCl or mannitol, or by reduction of distilled water. In Experiment 2, the diploids were cultured in the five media used in Experiment 1 for the first 48 h, and then in mWM256 until 168 h after El-St. In Experiment 3, the diploids were cultured for the first 48 h in mWM with osmolarity adjusted from 256 to 330 mOsmol by addition of NaCl for the first 48 h and then in mWM256 until 168 h after El-St. In Experiment 4, the diploids were cultured in mWM with 290 mOsmol (mWM290) for the first period of 24, 48, or 72 h, and then in mWM256 until 168 h after El-St. In Experiment 5, after diploids were cultured in mWM290 for the first 48 h, the obtained 4-cell diploids were transferred to mWM with osmolarity adjusted from 200 to 310 mOsmol by addition of NaCl, then cultured until 168 h after El-St. All media were supplemented with 0.5mg/ml hyaluronic acid and 4.0mg/ml bovine serum albumin. The results obtained in Experiments 1-5 indicate that the osmolarity of a medium, but not the Na(+)/K(+) ratio, exerts effects on the development of diploids to the blastocyst stage. The change of osmolarity of the culture media after the 4-cell stage increased the rate of expanded blastocyst formation in porcine diploids. The optimal osmolarities of culture medium for the first 48 h after El-St (before the 4-cell stage) were 290 and 280-320 mOsmol, and those for the later period (after the 4-cell stage) were 256 and 220-270 mOsmol, respectively.

Animals↗

[Surgically treated mucoepidermoid carcinoma in a 6-year-old boy; report of a case].

A 6-year-old boy was admitted to our hospital with a history of recurrent obstructive pneumonia and hemoptysis. A chest computed tomography (CT) showed atelectasis in the left lower lobe. Angiograpy, which was performed for the suspicion of pulmonary sequestration, showed no feeding artery and revealed bleeding from the bronchial artery in the left lower lobe. As hemoptysis would not stop, an emergency left lower lobectomy was performed. Macroscopic examination of the resected specimen revealed a mass measuring 20 x 15 x 17 mm in the S8 proximal lung parenchyma, bronchiectasis, and an abscess in the distal lung parenchyma. Histopathologic examination determined the tumor was a mucoepidermoid carcinoma. Immunohistochemical staining revealed some tumor cells were positive for CA 19-9. The child has not had a recurrence 3 years postoperatively.

Bronchial Neoplasms↗

Clinical and pathologic characteristics of nontyphoidal salmonella encephalopathy.

OBJECTIVE: To investigate the clinical and pathologic characteristics of primary encephalopathy caused by nontyphoidal salmonellosis (NTS). METHODS: Case records of six Japanese hospitals from 1994 to 1999 were reviewed. Eight cases of primary NTS encephalopathy were identified based on strictly defined criteria: 1) encephalopathic feature defined as altered state of consciousness, altered cognition or personality, or seizures; 2) detection of nontyphoidal Salmonella species in stool; 3) absence of other viral or bacterial infection associated with CNS abnormalities; and 4) absence of alternative explanation by underlying neurologic or systemic disease. Three patients died, three had severe sequelae, and two recovered completely. The authors analyzed their clinical course, neurologic symptoms, and histopathologic findings. RESULTS: NTS encephalopathy was clinically characterized by diffuse and rapidly progressive brain dysfunction and circulatory failure that developed following enteritis. There was no evidence of severe dehydration or sepsis, and encephalopathy was rarely accompanied by abnormal laboratory data, except elevated CSF opening pressure, brain edema on CT, and slow waves on EEG. Pathologic findings included minimal ischemic damage and mild edema in the brain, microvesicular fatty change of the liver, severe enterocolitis but no evidence of dehydration, and no fatal organ damage including microvasculature and endothelial cells. CONCLUSION: Noninfectious encephalopathy associated with nontyphoidal salmonella infection is a distinctive clinical entity that can be differentiated from Reye's syndrome and Ekiri.

Adolescent↗

Tumour necrosis factor-alpha receptors are present in the corpus luteum throughout the oestrous cycle and during the early gestation period in pigs.

To determine the physiological significance of tumour necrosis factor-alpha (TNFalpha) in the regulation of luteal functions in pig, this study was conducted to identify the presence of functional TNFalpha receptors in porcine corpora lutea (CL) throughout the oestrous cycle and the early gestation. The CL were isolated from pigs on days 4, 6, 8, 12 or 15 of the oestrous cycle (n=3; day 0 = oestrus) and days 15, 20 or 25 of gestation (n=3; day 0 = mating). A Scatchard analysis revealed the presence of a high-affinity binding site for TNFalpha in all samples (dissociation constant; 2.7 +/- 0.51 to 5.8 +/- 0.50 nM). The concentration of TNFalpha receptors was higher on day 15 of the oestrous cycle than on days 4 and 8 of the oestrous cycle (p < 0.05). Furthermore, TNFalpha receptor concentrations in the CL on days 15, 20 and 25 of gestation were significantly lower than on day 15 of the oestrous cycle (p < 0.05). On day 9 of the oestrous cycle, exposure of cultured luteal cells to 0.06-60 nM TNFalpha stimulated prostaglandin (PG) F2alpha and PGE2 secretion in a dose-dependent manner (p < 0.05). These results indicate that functional TNFalpha receptors are present in the porcine CL throughout the oestrous cycle and early gestation, and suggest that TNFalpha plays one or more physiological roles in regulating CL function throughout the oestrous cycle and the early gestation period. In addition, TNFalpha receptor concentration in the CL of the late luteal stage (day 15) of the oestrous cycle was higher than on the respective day in the early pregnant pig, suggesting that TNFalpha plays a role in accomplishing luteolysis in the porcine CL.

Animals↗

Laparoscopic features of primary biliary cirrhosis in AMA-positive and AMA-negative patients.

BACKGROUND AND STUDY AIMS: Antimitochondrial antibody (AMA)-negative primary biliary cirrhosis (PBC) has been difficult to diagnose. Laparoscopic features of AMA-negative PBC were evaluated in comparison with those of AMA-positive PBC and autoimmune hepatitis. PATIENTS AND METHODS: 71 patients who fulfilled the diagnostic criteria for PBC were enrolled in the study; 48 were AMA-positive and 23 were AMA-negative. As a disease control, 46 autoimmune hepatitis patients were included. Both the frequency and specificity of each laparoscopic finding were evaluated. A laparoscopic scoring system was introduced, which used, common and uncommon laparoscopic findings, and was evaluated for the diagnosis of AMA-negative PBC. RESULTS: The characteristic laparoscopic findings for AMA-positive PBC were yellowish-white marking (92 %), dark-brown discoloration (73 %), gentle undulation (67 %), reddish patch (38 %), and yellowish-white nodules (32 %). On the other hand, laparoscopic findings such as trench-like depression, reddish markings, and wide and small depressions were uncommon in PBC compared with autoimmune hepatitis. The frequencies of characteristic and uncommon laparoscopic findings did not differ statistically between AMA-positive and AMA-negative PBC, but were different between AMA-positive or AMA-negative PBC and autoimmune hepatitis. Scores based on common and uncommon laparoscopic findings were 5.5 +/- 1.5 (mean +/- SD) in AMA-positive PBC, 5.6 +/- 2.0 in AMA-negative PBC, and - 0.30 +/- 0.5 in autoimmune hepatitis. CONCLUSION: The laparoscopic findings in AMA-negative PBC did not differ from those of AMA-positive PBC. A laparoscopic scoring system may be helpful in the diagnosis of AMA-negative PBC.

Adult↗

Accelerated death kinetics of Aspergillus niger spores under high-pressure carbonation.

The death kinetics of Aspergillus niger spores under high-pressure carbonation were investigated with respect to the concentration of dissolved CO2 (dCO2) and treatment temperature. All of the inactivation followed first-order death kinetics. The D value (decimal reduction time, or the time required for a 1-log-cycle reduction in the microbial population) in the saline carbonated at 10 MPa was 0.16 min at 52 degrees C. The log D values were linearly related to the treatment temperature and the concentration of dCO2, but a significant interaction was observed between them.

Aspergillus niger↗

The association of K-ras gene mutation and vascular endothelial growth factor gene expression in pancreatic carcinoma.

BACKGROUND: Previously, the authors reported the role of the vascular endothelial growth factor (VEGF) as an angiogenic factor in 40 patients with pancreatic carcinoma. In this study, they investigated the mechanism underlying the regulation of VEGF gene expression and evaluated VEGF expression and K-ras gene status in 48 patients with pancreatic carcinoma. METHODS: The authors used quantitative reverse transcriptase-polymerase chain reaction analysis and direct sequencing techniques for a retrospective study of VEGF gene expression and K-ras gene status in tumor tissue samples from 48 patients with pancreatic carcinoma. Immunohistochemistry also was used to investigate VEGF protein expression. RESULTS: Thirty-one tumors (64.6%) were evaluated with high VEGF expression, and 17 tumors (35.4%) were evaluated with low VEGF expression. Of the 48 primary pancreatic tumors studied, 33 tumors (68.8%) contained mutations of the K-ras gene. There was a significant correlation between VEGF expression and K-ras status. Twenty-five of 33 tumors (75.8%) with mutant K-ras genes showed high VEGF expression, whereas only 6 of 15 tumors with the wild type K-ras (40.0%) showed high VEGF expression (P = 0.038). The mean (+/- standard error) VEGF conservation rate for the 33 tumors with mutant K-ras was 1.839 +/- 1.241, and that for the 15 tumors with wild type K-ras was 1.057 +/- 0.983 (P = 0.037). Furthermore, the median survival for patients with mutant K-ras was shorter than for those with wild type K-ras (10.6 months vs. 27.6 months, respectively; P = 0.026), whereas the median survival for patients with high VEGF expression was shorter compared with that for patients with low VEGF expression (9.5 months vs. 26.4 months, respectively; P = 0.002). Cox regression model analysis indicated that only the VEGF status was a significant factor for prognosis (P = 0.024). Other variables, i.e., K-ras status, histopathologic tumor grade, tumor status, lymph node status, metastatic status, gender, and age at surgery, were not significant. CONCLUSIONS: The results of this study suggest that K-ras oncogene mutation may be associated with VEGF expression and that patients with pancreatic carcinoma who have high VEGF expression are associated with a poor prognosis.

Biomarkers, Tumor↗

An inhibitory factor for cell-free protein synthesis from Salmonella enteritidis exhibits cytopathic activity against Chinese hamster ovary cells.

A factor inhibiting cell-free protein synthesis was purified from Salmonella enteritidis cell lysate by sequential ammonium sulfate precipitation, chromatography on anion exchange and hydrophobic interaction columns, and polyacrylamide disc gel electrophoresis. The purified factor, which was named SIPS (Salmonella inhibitor of protein synthesis), inhibited in vitro protein synthesis in rabbit reticulocyte lysate and had a molecular mass of 38 kDa, estimated by PAGE under denaturing conditions. SIPS was also cytopathic for Chinese hamster ovary cells. The N-terminal amino acid sequence (20 residues) of SIPS was found to be identical to that of mature L-asparaginase II of Escherichia coli. Indeed, the purified SIPS exhibited asparaginase activity, E. coli L-asparaginase II had cytopathic activity and inhibited in vitro protein synthesis. The results suggest that at least a part of cytotoxicity and inhibition of cell-free protein synthesis caused by S. enteritidis is a property of the bacterial L-asparaginase.

Animals↗

Neutral endopeptidase/CD10 and aminopeptidase N/CD13 gene expression as a prognostic factor in non-small cell lung cancer.

OBJECTIVES: Neutral endopeptidase modulates the growth of lung cancer, while aminopeptidase N degrades the extracellular matrix and is involved in cell motility. We studied the metastasis mechanism to detect novel metastasis-associated molecules and to evaluate them for clinical application. METHODS: We studied the relationship between the expression of neutral endopeptidase and aminopeptidase N by quantitative reverse transcript-polymerase chain reaction analysis in 132 patients with non-small cell lung cancer undergoing radical surgery from 1991 to 1996. RESULTS: Patients with neutral endopeptidase-positive and aminopeptidase N-negative tumors were defined as group A, those with neutral endopeptidase-positive and aminopeptidase N-positive or neutral endopeptidase-negative and aminopeptidase N-negative tumors as group B, and those with neutral endopeptidase-negative and aminopeptidase N-positive tumors as group C. The 5-year survival of group A patients (92.9%) was significantly better than that of group B patients (64.7%) and much better than that of group C patients (38.2%) (P = 0.0011). Neutral endopeptidase and aminopeptidase N thus have statistically significant P in overall survival in Cox regression (P = 0.019). CONCLUSION: Neutral endopeptidase and aminopeptidase N gene expressions are significant indicators of prognosis.

Adult↗