Biomedical subjects

K Miyauchi

Publications and source records attributed to K Miyauchi.

At least 19 recordsLinked to original sources

PubMed2006

Influence of administration methods on the accumulation of ALA-induced Pp-IX in mouse tongue tumors.

OBJECTIVE: 5-Aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) has been used as a photosensitizer in photodynamic therapy (PDT) for oral cancer. This study investigates the optimal method of administrating ALA by analyzing PpIX fluorescence in tongue tumor tissue. METHODS: Protoporphyrin IX intensities in the mouse (C3H)-transplanted tongue cancer (NR-S1) were compared with those in normal tongue after intraperitoneal (i.p.), oral (p.o.) or topical administration of ALA. Tongues were sampled at various times after ALA administration. PpIX intensities were obtained from frozen sections of each sample by using a spectrophotometer. RESULTS: Protoporphyrin IX intensity in the tumor group peaked at 3 h after the i.p. and 5 h after the p.o. administration of ALA, and these levels were about twice as high as those in the normal group. Maximum PpIX accumulation in the tongue tumor tissue was seen at 5 h after p.o. administration of ALA. In contrast, the topical administration of 20% ALA cream was associated with the lowest PpIX accumulation in the tumor throughout the experiments. CONCLUSION: These results suggested that p.o. administration of ALA was the most effective method in ALA-PDT for oral cancer.

Administration, Oral↗

PubMed2005

[Congenital cystic adenomatoid malformation detected by prenatal sonography; report of 2 cases].

We report 2 cases of congenital cystic adenomatoid malformation (CCAM) detected by prenatal sonography. The first CCAM was diagnosed by fetal sonography in a female fetus at 30 weeks' gestation. The infant was born at 37 weeks' gestation, with a body weight of 2,770 g. After birth, chest computed tomography (CT) showed a multicystic mass in the middle lobe of the lung. She remained asymptomatic until age 21 months, when she suffered pneumonia. Two months later, middle lobectomy was performed. The second CCAM was diagnosed by fetal sonography in a female fetus at 25 weeks' gestation. She was born at 39 weeks' gestation, with a body weight of 3,292 g. Four days after birth, CCAM type II was diagnosed by chest CT. The infant was asymptomatic, and left lower lobectomy was performed 11 months after birth.

Cystic Adenomatoid Malformation of Lung, Congenita↗

PubMed2004

Electron bunch trapping and compression by an intense focused pulse laser.

A focused short-pulse laser of TEM (1,0)+TEM (0,1) mode has two intensity peaks in the radial direction, so that the transverse ponderomotive force may trap electrons between the two peaks. At the same time the longitudinal ponderomotive force may accelerate electrons at the head of the laser pulse, when the laser is focused. When the electrons move to the laser tail, the laser may diverge and the electron deceleration becomes relatively weak. Our numerical analyses demonstrate that electrons are trapped well by the laser potential well, and that at the same time the acceleration by the longitudinal ponderomotive force induces the electron bunch compression. This trapping and compression mechanism is unique: the electron bunch can be compressed to the scale of the laser pulse length.

Journal Article↗

PubMed2004

Effects of toremifene (TOR) and tamoxifen (TAM) on serum lipids in postmenopausal patients with breast cancer.

This study clarified the difference in the effects on serum lipids between toremifene (TOR) and tamoxifen (TAM). To remove influencing factors, we investigated adjuvant therapy for hormone receptor-positive patients with breast cancer without lymph node metastasis. The subjects were 65 patients who were enrolled in a multicenter randomized comparative study between April 1997 and March 2001. As adjuvant therapy, 20 mg of TAM or 40 mg of TOR was administered for 1 year. The levels of triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A-1 (Apo A-1), apolipoprotein A(Apo B), and lipoprotein a (Lp(a)) were measured prior to administration and 3, 6, and 12 months after the start of administration. TC, LDL-C, Lp(a) and Apo B significantly decreased from the third month of administration compared with values before the start of administration in both the TOR and TAM groups. HDL-C significantly increased from the third month only in the TOR group. TG significantly increased in the TAM group but significantly decreased in the TOR group in the 12th month of administration. When these two groups were compared, HDL-C was significantly higher (p < 0.01) and TG was significantly lower (p < 0.01) in the TOR group in the 12th month. Improvement of abnormal values of TG, HDL-C and LDL-C was better in the TOR group than in the TAM group after administration for 12 months. The effect on lipid metabolism showed different profiles between the two selective estrogen receptor modulators (SERMs), and TOR gave better results than TAM.

Adult↗

PubMed2004

Alterations in enzyme histochemical characteristics of the masseter muscle caused by long-term soft diet in growing rabbits.

OBJECTIVE: Recently young people have an increasing tendency to intake an easily chewable diet and spend less time on mastication. The aim of the present study was to investigate the histochemical effects of long-term soft diet on the masseter muscle in growing rabbits. MATERIALS AND METHODS: Twelve young male Japanese white rabbits were divided into two groups (n = 6 each) at weaning (1 month after birth) and fed a solid diet (control group) or a powder diet (soft-diet group). The duration of the experimental period was 6 months. Masseter fibers from the superficial and the deep portions were histochemically defined as type 1, 2A, 2B, or 2C fibers. RESULTS: As compared with that of the control, the deep masseter of the soft-diet group showed a significantly lower ratio of type 1 fiber cross-sectional area to total area (6.3 and 10.1% for the soft-diet and control group, respectively), significantly more type 2A fibers (74.0%vs 50.3%) and significantly fewer type 2B fibers (4.3%vs 12.5%). However, fiber size did not differ between the two groups. NADH-tetrazolium-reductase (NADH-TR) of the masseter was less reactive in the soft-diet group, reflecting a lower oxidative capacity. CONCLUSIONS: These findings indicate that the alteration of the functional activities contributed to selective disuse influences on the type 1 and type 2B fibers, and a resultant increase in type 2A fibers. This study suggests that long-term alteration of jaw function induced by a soft diet can lead to adaptations of the masseter muscle.

Adaptation, Physiological↗

PubMed2003

Mucoepidermoid carcinoma of the esophagus treated by endoscopic mucosal resection.

Mucoepidermoid carcinoma is a mixed cell tumor with both adenocarcinomatous and squamous components. We report a rare case of superficial mucoepidermoid carcinoma of the esophagus with mucosal gastric cancer. Endoscopic mucosal resection was performed on a 67-year-old man with a slight but defined depressed lesion of the thoracic esophagus and two lesions of mucosal gastric cancer. Histological examination revealed that the lesion of the esophagus was a mucoepidermoid carcinoma and the two lesions of the stomach were well-differentiated adenocarcinoma. Since the mucoepidermoid carcinoma had only slightly invaded the submucosal layer, it was thought to arise from the ductal epithelium of the esophageal gland or the stratified squamous epithelium of the esophagus. Radiation therapy with a total dose of 60 Gy was performed and there has been no recurrence or metastasis to other organs during 36 months of follow-up.

Aged↗

PubMed2003

[Lung cancer associated with the right aortic arch; report of a case].

We report a rare case of lung cancer associated with the right aortic arch. A 72-year-old male was admitted to our hospital for surgical treatment of squamous cell carcinoma arising from left B3. The patient had a right aortic arch with the type of mirror-image branching. He underwent a left upper lobectomy and lymph node dissection. We easily resected the lymph nodes in the left side of the upper mediastinum without rotating aortic arch because the aortic arch was positioned on the other side.

Aged↗

PubMed2002

Concomitant laparoscopic splenectomy and cholecystectomy as an effective and minimally invasive treatment of pyruvate kinase deficiency with gallstones.

A 4-year-old girl with pyruvate kinase deficiency underwent partial splenic embolization initially. However, even after this procedure, she still had to be transfused every 2 months and then every month. At 5 years of age, she was admitted to our hospital to undergo splenectomy. She underwent laparoscopic splenectomy and concomitant cholecystectomy for gallstones. The hemogram recovered to the normal range after surgery, and her postoperative course was uneventful. Considering the absence of morbidity, the short hospitalization, the quick return to normal activity, the good cosmetic result, and the improved clinical and hematologic results, we consider that simultaneous laparoscopic splenectomy and cholecystectomy is safe and effective for the management of hemolytic anemia resulting from pyruvatre kinase deficiency and associated with cholelithiasis.

Child, Preschool↗

PubMed2002

Molecular cloning and characterization of mouse calcitonin gene-related peptide receptor.

The calcitonin gene-related peptide (CGRP) plays important roles as a neurotransmitter/neuromodulator in the central nervous system, and as a potent vasodilator when secreted from peripheral, perivascular nerves through its specific receptors. In this study, we cloned mouse cDNA counterparts of the human CGRP receptor composed of calcitonin receptor-like receptor (CRLR) and receptor activity modifying protein 1 (RAMP1) and examined the signal transduction mechanism through the CGRP receptor. Mouse CRLR (mCRLR) is a 462-amino acid G protein-coupled heptahelical receptor, and mouse RAMP1 (mRAMP1) is a 148-amino acid single membrane-spanning protein with a short cytoplasmic portion. Specific binding of (125)I-CGRP was detected only when both mCRLR and mRAMP1 cDNAs were cotransfected to COS-7 cells, and the Kd value of the receptor was 2.2 x 10(-10) M. CGRP induced a marked elevation of the intracellular cAMP levels in COS-7 cells cotransfected with mCRLR and mRAMP1. CGRP signaling through the mCRLR/mRAMP1 receptor complex was found to increase the promoter activities of cyclic AMP responsive element and serum responsive element in the co-transfected HeLa cells. These results indicate that mCRLR and mRAMP1 constitute a functional mouse CGRP receptor for the transduction of CGRP signaling by PKA and extracellular signal-regulated kinase signal transduction pathways.

Amino Acid Sequence↗

PubMed2001

Surgical technique for combined intestine-auxiliary liver transplantation in rats: development of a new microsurgical model.

Combined liver-intestine transplantation is an evolving procedure, and auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. We present a new model of combined intestine-auxiliary liver transplantation in rats. Total small bowel and 60% liver were harvested en bloc. An aortic segment that contained the celiac axis and superior mesenteric artery ensured blood supply to the graft. Venous drainage of the grafted intestine was achieved via the intact portal vein of the graft. The infrahepatic vena cava was cut at different levels during the modification period and at the oblique level of the left renal vein in consecutive series. Revascularization was accomplished by end-to-side anastomosis of the aorta and of the infrahepatic vena cava. The recipient small bowel was resected and the intestine continuity restored by anastomosis. Total operation time averaged 130 min. The overall survival rate of 3 months in the consecutive series was 80% (16/20). Exploratory laparatomy and histologic study in 3 rats on 90 days after transplantation revealed normal and viable grafts. Liver function was normal and both grafted liver and intestine showed normal histologic architectures in 5 rats observed for 12 months after transplantation. The present model is reproducible and allows preclinical research on several aspects of experimental combined intestine-auxiliary liver transplantation.

Animals↗

PubMed2001

Cardiac surgery in patients with end-stage renal disease. Utility of continuous ambulatory peritoneal dialysis.

OBJECTIVES: The number of patients with end-stage renal disease undergoing open heart surgery continues to grow. We evaluated continuous ambulatory peritoneal dialysis and the extracorporeal ultrafiltration method during cardiopulmonary bypass in the management of these difficult patients. METHODS: These 2 methods were used in 4 patients with renal failure who underwent open heart surgery between July 1997 and March 1999. Preoperative continuous ambulatory peritoneal dialysis was conducted using standard protocols. Extracorporeal ultrafiltration method was used only during cardiopulmonary bypass. Continuous ambulatory peritoneal dialysis was initiated upon arrival at the intensive care unit. Mean follow-up was 12 months. RESULTS: Postoperative blood urea nitrogen and creatinine concentrations were lower than preoperative concentrations. No patients required hemodialysis. All 4 patients were discharged to their homes. No deaths occurred. CONCLUSIONS: Continuous ambulatory peritoneal dialysis and extracorporeal ultrafiltration method are combined to treat patients with end-stage renal disease who require open heart surgery. This combination is simple, and does not require specialized personnel, and obviates the hemodynamic instability associated with hemodialysis.

Aged↗

PubMed2001

Cloning and characterization of benzoate catabolic genes in the gram-positive polychlorinated biphenyl degrader Rhodococcus sp. strain RHA1.

Benzoate catabolism is thought to play a key role in aerobic bacterial degradation of biphenyl and polychlorinated biphenyls (PCBs). Benzoate catabolic genes were cloned from a PCB degrader, Rhodococcus sp. strain RHA1, by using PCR amplification and temporal temperature gradient electrophoresis separation. A nucleotide sequence determination revealed that the deduced amino acid sequences encoded by the RHA1 benzoate catabolic genes, benABCDK, exhibit 33 to 65% identity with those of Acinetobacter sp. strain ADP1. The gene organization of the RHA1 benABCDK genes differs from that of ADP1. The RHA1 benABCDK region was localized on the chromosome, in contrast to the biphenyl catabolic genes, which are located on linear plasmids. Escherichia coli cells containing RHA1 benABCD transformed benzoate to catechol via 2-hydro-1,2-dihydroxybenzoate. They transformed neither 2- nor 4-chlorobenzoates but did transform 3-chlorobenzoate. The RHA1 benA gene was inactivated by insertion of a thiostrepton resistance gene. The resultant mutant strain, RBD169, neither grew on benzoate nor transformed benzoate, and it did not transform 3-chlorobenzoate. It did, however, exhibit diminished growth on biphenyl and growth repression in the presence of a high concentration of biphenyl (13 mM). These results indicate that the cloned benABCD genes could play an essential role not only in benzoate catabolism but also in biphenyl catabolism in RHA1. Six rhodococcal benzoate degraders were found to have homologs of RHA1 benABC. In contrast, two rhodococcal strains that cannot transform benzoate were found not to have RHA1 benABC homologs, suggesting that many Rhodococcus strains contain benzoate catabolic genes similar to RHA1 benABC.

Base Sequence↗

PubMed2001

Association of seropositivity for antibody to Chlamydia-specific lipopolysaccharide and coronary artery disease in Japanese men.

Recent studies suggest an association between Chlamydia pneumoniae infection and coronary artery disease (CAD). To examine this relationship in Japanese men, serum IgA and IgG antibodies to Chlamydia-specific lipopolysaccharide were measured by enzyme-linked immunosorbent assay in 507 patients with CAD and 200 age-matched controls. CAD patients were divided into (1) 269 patients with myocardial infarction (MI) and (2) 238 patients with chronic coronary heart disease (CCHD). Compared with the control group, the CAD group did not differ in the prevalences of both antibodies (IgA: 23.7 vs 18.0%, p=0.10; IgG: 52.7 vs 51.0%, p=0.6). The index of IgG antibody was not significantly different between CAD and control groups (median 1.19 vs 1.18, p=0.3), whereas the index of IgA antibody was significantly higher in CAD than control group (median 0.60 vs 0.46, p<0.0001). Compared with the control group, the MI group had a significantly higher prevalence of IgA antibody (28.6 vs 18.0%, p=0.007); however, there was no difference in the prevalence of IgG antibody (58.0 vs 51.0%, p=0.13). The CCHD group did not differ in the prevalences of both antibodies (IgA: 18.1 vs 18.0%, p=0.9; IgG: 45.6 vs 51.0%, p=0.2). After the adjustment for coronary risk factors, odds ratios (ORs) of seropositive antibodies for CAD were 1.59 [95% confidence interval (CI): 0.88-2.87, p=0.12] for IgA seropositivity and 0.92 (95%CI: 0.58-1.47, p=0.7) for IgG seropositivity in all cases. In the MI and control groups, ORs of seropositive antibodies for MI were 2.67 (95%CI: 1.32-5.38, p=0.007) for IgA seropositivity, and 1.36 (95%CI: 0.79-2.36, p=0.2) for IgG seropositivity. This study discovered that IgA antibody to Chlamydia was significantly associated with CAD, especially with MI, in Japanese Men and the findings suggest that chronic infection of Chlamydia may be linked to the pathogenesis of MI.

Aged↗

PubMed2000

Effect of probucol on repeat revascularization rate after percutaneous transluminal coronary angioplasty (from the Probucol Angioplasty Restenosis Trial [PART]).

To address the issue of whether probucol reduces clinical events after percutaneous transluminal coronary angioplasty (PTCA), we surveyed clinical status at 1 year after PTCA of 101 patients who had entered the Probucol Restenosis Angioplasty Trial. Repeat angioplasty at index lesions were required in 5 patients in the probucol group and in 12 in the control group, suggesting that probucol administered beginning 4 weeks before PTCA reduces repeat revascularization rates for 1 year.

Angioplasty, Balloon, Coronary↗

PubMed2000

Attenuated coronary flow reserve and vascular remodeling in patients with hypertension and left ventricular hypertrophy.

OBJECTIVES: The purpose of this study was to evaluate the association between hypertension and left ventricular hypertrophy (LVH) with both coronary vascular remodeling and endothelial function. BACKGROUND: The association between endothelial and nonendothelial coronary flow reserve with vascular remodeling in patients with hypertension and LVH is still unclear. METHODS: One hundred and eleven patients with normal or mildly diseased coronary arteries at angiography underwent intravascular ultrasound examination of the left anterior descending coronary artery. Patients were divided into three groups: group 1: n = 13, hypertensive patients with LVH; group 2: n = 30, hypertensive patients without LVH; group 3: n = 68, normotensive patients. Vessel and lumen area and atherosclerotic plaque area were evaluated. Vascular reactivity was examined using intracoronary adenosine and acetylcholine. RESULTS: Vessel area in group 1 (with LVH) was significantly (p < 0.01) greater than that in group 2 (without LVH), whereas, vessel area in both groups 1 and 3 was similar (12.8 +/- 0.8 mm2, 10.7 +/- 0.4 mm2 and 11.5 +/- 0.3 mm2). Coronary blood flow at baseline for patients in group 1 (with LVH) was significantly greater than it was for patients in groups 2 and 3 (81.1 +/- 9.9 ml/min, 56.5 +/- 6.2 ml/min and 48.1 +/- 3.2 ml/min, both p < 0.05). In comparison with groups 2 and 3, the response to both acetylcholine and adenosine was significantly impaired in patients with LVH. CONCLUSIONS: The current study demonstrates that hypertension with LVH is associated with both coronary vascular remodeling and attenuated endothelial and nonendothelial coronary flow reserve.

Acetylcholine↗

PubMed2000

Successful endoscopic resection of intramural metastasis after esophagectomy for esophageal cancer: a case report.

Carcinoma of the esophagus is often accompanied by intramural metastasis (IM) at the time of diagnosis, and the prognosis of patients with such metastasis is very poor. Here we report the case of a 60-year-old man who presented with a submucosal tumor in the wall of the cervical esophagus at 2 years after esophagectomy for thoracic esophageal cancer. The tumor was resected endoscopically and was histologically shown to be an IM of esophageal cancer. He has shown no recurrence and no metastasis during 2 years of follow-up after endoscopic resection and radiation therapy.

Carcinoma, Squamous Cell↗

PubMed2000

Development of battery charging system for the FE gun system of HVEM.

We have developed a reliable and efficient battery-charging system for the field emission (FE) gun system of high voltage electron microscopes, where the operating condition of the whole FE gun system can be controlled and monitored through a bi-directional optical fiber system, and the control and monitoring circuits located on the high potential of 1 MV are driven by rechargeable Ni-Cd batteries. The power transmission from ground to the high potential is performed through filter condenser circuit. Under the condition that the filter condenser current is limited to 0.2 A(rms) (root-mean-square value), it is possible to transmit the maximum power as high as 65 W, which is enough for the daily operation of the FE gun system. The charging circuit has a function of protecting the batteries from over-charging.

Journal Article↗

PubMed2000

Cholesterol-lowering treatment is associated with improvement in coronary vascular remodeling and endothelial function in patients with normal or mildly diseased coronary arteries.

Coronary vascular remodeling and altered endothelial function have been described in the early stages of native atherosclerosis. The purpose of this study was to evaluate the association between cholesterol-lowering therapy and coronary vascular remodeling and endothelial function in patients with normal or mildly diseases coronary arteries. Patients (N=101) with normal or mildly diseased coronary arteries by coronary angiography underwent intravascular ultrasound examination of the left anterior descending coronary artery. Vessel and lumen area, atherosclerotic plaque area, and plaque morphology were evaluated. Vascular reactivity was examined with the use of intracoronary adenosine, acetylcholine, and nitroglycerin. Patients were divided into 3 groups based on the total cholesterol levels: group 1 (n=25), patients with a history of hypercholesterolemia adequately treated (total cholesterol <240 mg/dL); group 2 (n=26), patients with hypercholesterolemia not adequately controlled (total cholesterol >/=240 mg/dL); and group 3 (n=50), patients without hypercholesterolemia. Vessel area and lumen area were significantly greater in groups 1 and 3 than in group 2 (for respective values in groups 1, 2, and 3: vessel area 11.9+/-0.5, 10.6+/-0.4, and 11.8+/-0.4 mm(2), both P<0.05; lumen area 8.3+/-0.4, 6.9+/-0.3, and 8.9+/-0.3 mm(2), both P<0.01). However, plaque areas in groups 1 and 2 were similar. Furthermore, acetylcholine-induced percent increases in coronary blood flow were significantly greater in groups 1 and 3 than in group 2 (for respective values in groups 1, 2, and 3: 70.5+/-20.1%, 22.8+/-13.7%, and 68.6+/-14.8%, both P<0. 05). Cholesterol-lowering treatment is associated with an improvement in coronary lumen area that results not from a decrease in plaque area but from an increase in vessel area, reflecting vascular remodeling. Additionally, this adaptive process may occur in association with an improvement of endothelium-dependent vasodilation of the resistance coronary artery.

Anticholesteremic Agents↗