Biomedical subjects

H Hirose

Publications and source records attributed to H Hirose.

At least 19 recordsLinked to original sources

PubMed2007

Mobile phone base station-emitted radiation does not induce phosphorylation of Hsp27.

An in vitro study focusing on the effects of low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields act to induce phosphorylation and overexpression of heat shock protein hsp27. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced activation or gene expression of hsp27 and other heat shock proteins (hsps). Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80 and 800 mW/kg for 2-48 h, and CW radiation at 80 mW/kg for 24 h. Human IMR-90 fibroblasts from fetal lungs were exposed to W-CDMA at 80 and 800 mW/kg for 2 or 28 h, and CW at 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the expression levels of phosphorylated hsp27 at serine 82 (hsp27[pS82]) were observed between the test groups exposed to W-CDMA or CW signal and the sham-exposed negative controls, as evaluated immediately after the exposure periods by bead-based multiplex assays. Moreover, no noticeable differences in the gene expression of hsps were observed between the test groups and the negative controls by DNA Chip analysis. Our results confirm that exposure to low-level RF field up to 800 mW/kg does not induce phosphorylation of hsp27 or expression of hsp gene family.

Brain Neoplasms↗

PubMed2007

Surgical resection of solitary adrenal metastasis from esophageal carcinoma following esophagectomy.

The prognosis of esophageal carcinoma following esophagectomy is poor due to a high frequency of metastasis to periesophageal lymph nodes and distant organs. However, we experienced a case with good prognosis following resection of a solitary adrenal metastatic tumor. The patient was a 70-year-old man diagnosed with type 2 esophageal cancer (Lt-Ae, T2N1M0, Stage IIB) who was treated with esophagectomy. Eight months following surgery, solitary adrenal metastasis was detected by CT, and was resected. At 42 months follow-up he has had a good quality of life in the community without evidence of recurrence. To the best of our knowledge, only five cases with resected solitary adrenal metastases including our case, have been reported, and show a greater than 1-year survival. Consequently, we suggest that resection of solitary organ metastases is a good alternative, even following esophagectomy.

Adrenal Gland Neoplasms↗

PubMed2006

Electromyography of the cricoarytenoid unit during supracricoid laryngectomy with a cricohyoidoepiglottopexy procedure.

Two patients who received supracricoid laryngectomy with cricohyoidoepiglottopexy to treat laryngeal cancers, underwent intra-operative electromyography analysis. After the lesion was removed and the electrodes were inserted into the remaining intrinsic laryngeal muscles, the depth of anaesthesia was carefully reduced. Gentle tactile stimulations were applied to the pharynx to trigger the reflex movement of the remaining arytenoids. Recordings were made when reflex movement was achieved. Case one: Electromyography (EMG) of the remaining arytenoid demonstrated clear phase differences indicating reciprocal activities between the adductor group (lateral cricoarytenoid muscle, interarytenoid muscle) and the abductor muscle (posterior cricoarytenoid muscle). Case two: EMG of the remaining arytenoid demonstrated reciprocal activities between the interarytenoid muscle and the posterior cricoarytenoid muscle. Activity of the lateral cricoarytenoid muscle was not evident because the muscle was excised during removal of the paraglottic space. Mobility of the arytenoid was attributed to interaction between the interarytenoid muscle and posterior cricoarytenoid muscle. Reciprocal interaction between the interarytenoid muscle and posterior cricoarytenoid muscle alone is also capable of maintaining post-operative laryngeal functions after supracricoid laryngectomy with cricohyoidoepiglottopexy.

Aged↗

PubMed2006

DNA strand breaks are not induced in human cells exposed to 2.1425 GHz band CW and W-CDMA modulated radiofrequency fields allocated to mobile radio base stations.

We conducted a large-scale in vitro study focused on the effects of low level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system in order to test the hypothesis that modulated RF fields may act as a DNA damaging agent. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced different levels of DNA damage. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts from fetal lungs were exposed to mobile communication frequency radiation to investigate whether such exposure produced DNA strand breaks in cell culture. A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 2 and 24 h, while IMR-90 cells were exposed to both W-CDMA and CW radiations at a SAR of 80 mW/kg for the same time periods. Under the same RF field exposure conditions, no significant differences in the DNA strand breaks were observed between the test groups exposed to W-CDMA or CW radiation and the sham exposed negative controls, as evaluated immediately after the exposure periods by alkaline comet assays. Our results confirm that low level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.

Cell Line↗

PubMed2006

Phosphorylation and gene expression of p53 are not affected in human cells exposed to 2.1425 GHz band CW or W-CDMA modulated radiation allocated to mobile radio base stations.

A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields induce apoptosis or other cellular stress response that activate p53 or the p53-signaling pathway. First, we evaluated the response of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and wideband code division multiple access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced apoptosis or any signs of stress. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg, and CW radiation at 80 mW/kg for 24 or 48 h. Human IMR-90 fibroblasts from fetal lungs were exposed to both W-CDMA and CW radiation at a SAR of 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the percentage of apoptotic cells were observed between the test groups exposed to RF signals and the sham-exposed negative controls, as evaluated by the Annexin V affinity assay. No significant differences in expression levels of phosphorylated p53 at serine 15 or total p53 were observed between the test groups and the negative controls by the bead-based multiplex assay. Moreover, microarray hybridization and real-time RT-PCR analysis showed no noticeable differences in gene expression of the subsequent downstream targets of p53 signaling involved in apoptosis between the test groups and the negative controls. Our results confirm that exposure to low-level RF signals up to 800 mW/kg does not induce p53-dependent apoptosis, DNA damage, or other stress response in human cells.

Amino Acid Sequence↗

PubMed2005

Effects of exposure to a 1950 MHz radio frequency field on expression of Hsp70 and Hsp27 in human glioma cells.

Human glioma MO54 cells were used to investigate whether radio frequency (RF) field exposure could activate stress response genes. Cells were exposed to continuous wave 1950 MHz or sham conditions for up to 2 h. Specific absorption rates (SARs) were 1, 2, and 10 W/kg. For the cell growth experiment, cell numbers were counted at 0-4 days after exposure. Expression of Hsp27 and Hsp70, as well as the level of phosphorylated Hsp27 (78Ser) protein, was determined by Western blotting. It was found that sham exposed and RF exposed cells demonstrated a similar growth pattern up to 4 days after RF field exposure. RF field exposure at both 2 and 10 W/kg did not affect the growth of MO54 cells. In addition, there were no significant differences in protein expression of Hsp27 and Hsp70 between sham exposed and RF exposed cells at a SAR of 1, 2, or 10 W/kg for 1 and 2 h. However, exposure to RF field at a SAR of 10 W/kg for 1 and 2 h decreased the protein level of phosphorylated Hsp27 (78Ser) significantly. Our results suggest that although exposure to a 1950 MHz RF field has no effect on cell proliferation and expression of Hsp 27 and Hsp70, it may inhibit the phosphorylation of Hsp27 at Serine 78 in MO54 cells.

Cell Line, Tumor↗

PubMed2005

Looped reconstruction of the internal and external iliac arteries in repair of abdominal aortic or iliac artery aneurysm with a bifurcated graft.

AIM: The aim of our study is to describe an original technique of distal anastomosis of a bifurcated graft, coining looped reconstruction, and our preliminary clinical experience. METHODS: This technique has been applied in 16 of 24 distal anastomoses of 12 patients with abdominal aortic aneurysm (AAA) and/or iliac artery aneurysm. Both the internal (IIA) and external iliac arteries (EIA) are transected and anastomosed with end-to-end fashion to reconstruct their continuity, and the limb of a bifurcated graft is anastomosed to the EIA with end-to-side fashion. RESULTS: Operative and in-hospital death, ischemic colitis, or ischemia of the lower extremities including blue toe syndrome has never occurred. All the 28 reconstructed IIAs and EIAs have been patent in 11 patients who could undergo early postoperative computed tomography scans with contrast medium. CONCLUSIONS: The looped reconstruction of the IIA and the EIA in repair of an AAA and/or an iliac artery aneurysm with a bifurcated graft is an anatomically easy and technically simple method.

Aged↗

PubMed2005

Stent placement for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal arteries.

In both superficial and deep femoral artery involvement, where angioplasty of the former is not suitable or feasible, angioplasty of the latter seems to be the method of choice and is a less invasive and efficient treatment particularly for limb threatening ischemia, an appropriate obstruction morphology provided. The authors describe a case of a 73-year-old man, with a rest pain of the foot and intermittent cyanosis of the toe, who underwent stent placement with transluminal angioplasty for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal artery. The patient's ankle brachial index was remarkably increased from 0.25 to 0.61, and the preoperative symptoms were improved.

Aged↗

PubMed2004

Extremely low frequency magnetic fields and the promotion of H2O2-induced cell death in HL-60 cells.

PURPOSE: To test whether exposure to an extremely low frequency magnetic field (60 Hz, 5 mT) affects hydrogen peroxide (H2O2)-induced cell death in human leukaemia HL-60 cells. MATERIALS AND METHODS: Cells were treated with H2O2 with or without exposure to an extremely low frequency magnetic fields. Viable cells, apoptotic and necrotic cells were determined by annexin V flow cytometry assay. The levels of apoptosis-related proteins (caspase-3, caspase-7, Bcl-2 and Bax) and poly(ADP-ribose) polymerase were detected using Western blotting. RESULTS: Simultaneous treatment with exposure to the magnetic field and H2O2 (85 or 100 microM) for 24 h increased the number of apoptotic and necrotic cells significantly, and significantly decreased the number of viable cells compared with cells treated with H2O2 alone. The protein levels of Bax and Bcl-2 showed no differences between H2O2-treated cells and those treated with both H2O2 and an extremely low frequency magnetic field. Exposure to the magnetic field also had no effect on H2O2-induced caspase-3 activation. However, the protein levels of active caspase-7 in cells simultaneously exposed to an extremely low frequency magnetic field and H2O2 for 2 and 8 h was higher than that of H2O2 treatment alone. In addition, simultaneous exposure to an extremely low frequency magnetic field and H2O2 caused poly(ADP-ribose) polymerase cleavage and induced early inactivation at 2 h, while H2O2 treatment alone did not produce this effect until 4 h. CONCLUSIONS: The data suggest that although the magnetic field itself cannot induce apoptosis and necrosis, it exerts a promoting effect on H2O2-induced cell death, and it demonstrates that caspase-7 as well as poly(ADP-ribose) polymerase might be involved in this process.

Apoptosis↗

PubMed2003

Experimental model to estimate intestinal viability using charge-coupled device microscopy.

BACKGROUND: Intraoperative assessment of intestinal viability following release of strangulation remains difficult. The aim of this study was to establish clinical standards for the evaluation of intestinal viability by charge-coupled device (CCD) microscopy. METHODS: A rat ileus model with strangulation for between 15 and 120 min was used. The images obtained by CCD microscopy were used to calculate maximum velocity (V (max)) ratio (ratio of V (max) of blood cell transition in the experimental segment to that in the reference segment) and S ratio (the ratio of S-the effective area of the vascular bed against the total area of the vascular bed-in the experimental segment to that in the reference segment). Rats were divided into group 1, comprising animals that survived for 7 days or more, and group 2, which consisted of animals that died within 4 days. RESULTS: V (max) ratio and S ratio in group 1 were both significantly higher than those in group 2 (P < 0.01). No death occurred at a V (max) ratio of 0.76 or higher and an S ratio of 0.61 or more, while there were no survivors with a V (max) ratio of 0.54 or less and an S ratio of 0.51 or less. CONCLUSION: V (max) ratio and S ratio could be used as indices for evaluation of intestinal viability.

Animals↗

PubMed2003

The intravenous xylitol tolerance test in non-lactating cattle.

Xylitol is a five-carbon sugar alcohol that is often used for treatment of ketosis in dairy cattle in Japan. An intravenous xylitol tolerance test (IVXTT, 0.1 g/kg, bolus injection through the jugular vein) was performed in 4 non-lactating cows (n = 4) and the results were compared with those of an intravenous glucose tolerance test (IVGTT) performed under equivalent conditions. The serum xylitol concentration reached a peak value (41.4+/-9.0 mg/dl) at 5 min, and then rapidly decreased and almost disappeared within 2 h. The C0 for xylitol was 56.9+/-16.6 mg/dl and the t(1/2) was 8.5+/-0.9 min. The administration of xylitol appeared to cause similar secretion of insulin to that caused by glucose. There was also a reduction in the concentration of free fatty acids. It seems that xylitol has value for the treatment of ketosis. However, rapid administration of xylitol appeared to have an osmotic diuretic action and might be a cause of dehydration.

Animals↗

PubMed2003

Hepatocyte growth factor gene transfer into the liver via the portal vein using electroporation attenuates rat liver cirrhosis.

Although a variety of gene transfer methods to the liver have been designed, there are some problems such as the transfection efficiency and safety. In the present study, we developed a modified method of gene transfer into the liver by infusion of plasmid DNA via the portal vein followed by electroporation. After green fluorescence protein gene transfer, transgene expressions were detected in 24 h, and then maximally at 3 days, and persisted for 3 weeks. Histological analysis revealed that very mild tissue damage was induced in the liver to which electroporation was applied. In the second study, human hepatocyte growth factor (HGF) was more detected in the liver injected with 500 microg of human HGF gene than 100 microg of human HGF gene. However, serum HGF did not increase with 100 or 500 microg of human HGF gene. Moreover, 500 microg of HGF gene transfer into the liver by using this method could achieve the long survival of all dimethylnitrosamine-treated rats and attenuate the fibrous regions in the liver. These results suggest that HGF gene transfer into the liver via the portal vein using electroporation might be one of the useful methods for the treatment of various liver diseases.

Animals↗

PubMed2003

Characteristics of F-wave in different stretched positions of the affected arm in patients with cerebrovascular diseases.

To investigate the effect of continued stretching of affected arms in patients with cerebrovascular disease (CVD), F-wave was tested from the abductor pollicis brevis (APB) during relaxation (trial 1) and 3 different continued stretches: stretched position with shoulder abduction (trial 2), stretched position with shoulder abduction and elbow extension (trial 3), and stretched position with shoulder abduction, elbow extension and wrist extension (trial 4) of the affected arm for 1 min. in 20 hemiparesis patients with moderate hypertonus (modified Ashworth scale of 2 or 3) caused by CVD (mean age of 49.5 years). Persistence and amplitude ratio of F/M in trial 2 were the same as those in trial 1. Persistence and amplitude ratio of F/M in trials 3 and 4 were significantly lower than those in trial 1. It was suggested that excitability of spinal neural function of the distal part, the APB, of the affected arm was reduced during continued stretching of the proximal part, shoulder and elbow joints, or all of the shoulder, elbow and wrist joints in hemiparesis patients with moderate hypertonus caused by CVD.

Adult↗

PubMed2002