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Hidetoshi Sato

Publications and source records attributed to Hidetoshi Sato.

At least 19 recordsLinked to original sources
PubMed2006

Fluorescence-suppressed Raman technique for quantitative analysis of protein solution using a micro-Raman probe, the shifted excitation method, and partial least squares regression analysis.

A practical Raman analyzing technique with suppression of the strong fluorescent background in order to obtain quantitative information is proposed in the present study. The technique is based on the shifted excitation method and partial least squares regression (PLSR) analysis. The Raman system consists of a single Raman spectrometer, a background-free electrically tunable Ti:Sapphire laser (BF-ETL), and a micro-Raman probe (MRP). The system allows one to obtain reliable shifted excitation Raman spectra with a simple operation. The PLSR analysis successfully provides quantitative information from the obtained spectra with the suppression of random noise including photon shot noise. The present study demonstrates that the technique is effective for extracting quantitative information concealed behind a fluorescent background that is more than 200 times stronger than the Raman signal.

Animals↗
PubMed2006

Microscopic polyangitis triggered by fungal infection.

We report a case of microscopic polyangitis associated with fungal infection. A 64-year-old man was admitted to our hospital because of renal dysfunction and high fever. He complained of arthralgia and myalgia. He was diagnosed with antineutrophil cytoplasmic antibody-related vasculitis and also had a fungal infection. We treated him with antibiotics including fluconazole. All symptoms disappeared as the infection resolved without the use of steroid therapy. We speculate that the deteriorating vasculitis could have been triggered by overproduction of cytokines in response to the fungal infection.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2005

Raman probe using a single hollow waveguide.

A simple Raman probe was realized using a single flexible hollow waveguide (HW). A HW coated with a silver film, which had reasonable transmission and little optical background noise, was used as a bidirectional transmission fiber for both the excitation and collection of Raman scattered light. The HW itself generated no Raman scattering or fluorescence noise during transmission. A complex filtering system at the end of the waveguide was thus unnecessary. In addition, the measured Raman spectra showed better signal-to-noise ratios than a conventional Raman fiber probe. The HW's suitability as a Raman fiber probe was also demonstrated.

Equipment Design↗
PubMed2005

Micro-optical fiber probe for use in an intravascular Raman endoscope.

We believe that we have developed the narrowest optical-fiber Raman probe ever reported, 600 microm in total diameter, that can be inserted into coronary arteries. The selection of suitable optical fibers, filters, and a processing method is discussed. Custom-made filters attached to the front end of a probe eliminate the background Raman signals of the optical fiber itself. The experimental evaluation of various optical fibers is carried out for the selection of suitable fibers. Measurement of the Raman spectra of an atherosclerotic lesion of a rabbit artery in vitro demonstrates the excellent performance of the micro-Raman probe.

Angioscopes↗
PubMed2005

First clinical experience of a novel penetration catheter for patients with severe coronary artery stenosis.

The study aimed to evaluate the efficacy of a novel penetration catheter for severe coronary artery disease. Severe coronary artery diseases such as chronic total occlusions or severe calcified stenoses sometimes obstruct the subsequent crossing of balloon catheter after successful wire crossing. A novel penetration over-the-wire catheter has been developed for severe coronary artery disease. The main shaft is a coreless stainless coil that consists of eight stranded stainless wires to cross through a severe stenosis by manual rotation. This device was applied during percutaneous coronary intervention for patients with severe coronary artery disease obstructing the subsequent crossing of balloon or microcatheters after successful wire crossing. Initial results were examined. Fourteen eligible patients were enrolled consecutively. Among those, 10 patients had chronic total occlusion and 7 patients showed severe angiographical calcification. The device was successfully crossed through the lesion and enabled subsequent dilatation in all patients without any complication. This new device enables the crossing of severe coronary artery stenoses and therefore favors further dilatation in this lesion subset.

Aged↗
PubMed2004

Steroid-sensitive nephrotic syndrome associated with positive C1q immunofluorescence.

A 21-year-old woman showed heavy proteinuria and edema. A light microscopic study of a renal biopsy specimen showed diffuse mild mesangial expansion, with borderline mesangial hypercellularity. An immunofluorescence study revealed dominant positive staining (3+) of C1q in the glomerular mesangium. Stainings for C3, C4, IgG, and IgM were weak or 1+. Staining for IgA was negative. Electron-dense deposits were present in the mesangial area. There was significant fusion of foot processes. There was no serological or clinical evidence of collagen disease. She was treated with oral prednisolone (initially, 40 mg/day). The proteinuria was alleviated and the patient remains in complete remission. The histopathological studies were compatible with C1q nephropathy, although the clinical outcome differed in a number of aspects. The clinical picture in the current patient appears to represent a very rare phenotype of nephritis.

Adult↗
PubMed2004

Excitation wavelength dependent surface-enhanced Raman spectra of a dipping film of azobenzene-containing long-chain fatty acid on a silver mirror.

Surface-enhanced Raman scattering (SERS) of dipping films of azobenzene-containing long-chain fatty acids, nAmH (n=8, 12, m=3, 5), on silver mirrors measured with a wide range of excitation wavelengths in the 457.9-1064 nm region is reported. The obtained Raman spectra show great SERS effect even with the 1064 nm excitation, and the excitation with 457.9, 476.5, and 488.0 nm gives surface-enhanced resonance Raman scattering (SERRS) due to the resonance effect of the symmetry-forbidden n-pi* transition of the azo group. Of particular note in the present study is that the SERS spectra with the excitation in the 532-1064 nm region yield Raman bands whose frequencies are almost identical to those bands in Raman spectra of nAmH in solid state while the SERRS spectra with the excitation in the 457.9-514.5 nm region show not only a set of bands which correspond to those of nAmH in the solid state but also a set of bands whose frequencies show a significant shift from those of the bands of nAmH in the solid state. These observations lead us to conclude that there are two kinds of molecular aggregates in the dipping films of azobenzene-containing long-chain fatty acid in which azobenzene moieties are condensed to form small bundles.

Azo Compounds↗
PubMed2004

Multiple elastofibromas.

Elastofibroma is an uncommon fibroelastic tumor or tumorlike process that usually occurs between the scapula and the chest wall of elderly patients. This condition is rarely reported in the dermatologic literature, because it infrequently arises in the skin or within the subcutaneous tissue. We present a 78-year-old man with 15 separate subcutaneous nodules on the buttocks and upper extremities together with bilateral subscapular nodules. All specimens taken from different lesions were histologically confirmed as elastofibromas. As far as we know, this case with 17 distinct elastofibromas demonstrates the largest number ever reported in a single patient. Although the pathomechanism of the occurrence of multiple elastofibromas is unknown, it should be included in the differential diagnosis of multiple subcutaneous nodules.

Aged↗
PubMed2004

Novel technique using intravascular ultrasound-guided guidewire cross in coronary intervention for uncrossable chronic total occlusions.

The experience of using a novel application of intravascular ultrasound (IVUS)-guided percutaneous coronary interventions for chronic total occlusions is reported in 2 cases. In the first case, an IVUS catheter was advanced into a side branch to identify the entry point of the major branch. In the second case, IVUS-guided penetration of the guidewire from the false lumen to the true lumen after causing a dissection was successful.

Aortic Dissection↗
PubMed2004

The influence of diabetes mellitus on plaque volume and vessel size in patients undergoing percutaneous coronary intervention.

We evaluated the influence of diabetes on plaque volume and vessel size at a reference segment in diabetic patients undergoing percutaneous coronary intervention using both angiograms and quantitative intravascular ultrasound. A total of 344 patients with 449 de novo coronary lesions including 97 diabetics (133 lesions) who underwent elective percutaneous coronary intervention under intravascular ultrasound guidance were included in this study. Eleven diabetic patients (19 lesions) received insulin and 52 patients (77 lesions) oral hypoglycemic drugs. The other 34 patients (37 lesions) received diet/exercise therapy alone. We measured vessel area (VA) and lumen area (LA) at proximal and distal reference segments by intravascular ultrasound, which were averaged. Plaque area (VA-LA) and % plaque area (100 x plaque area/VA) were subsequently calculated. Although VA was similar between diabetic and non-diabetic patients (13.46 +/- 4.49 mm2 in diabetics versus 14.11 +/- 5.24 mm2 in non-diabetics, P = 0.214), LA was smaller (6.51 +/- 2.63 mm2 versus 7.38 +/- 3.08 mm2, P = 0.004) and % PA was larger (50.4 +/- 11.7 versus 46.5 +/- 11.3, P < 0.001) in diabetic patients, especially the group receiving a hypoglycemic drug or insulin. VA, LA, and % PA were similar between patients with and without insulin treatment. These results potentially might cause undersized device selection without intravascular ultrasound guidance.

Aged↗
PubMed2004

Squamous metaplasia mimicking papillary carcinoma in the upper urinary tract.

We experienced a case of squamous metaplasia mimicking papillary urothelial cell carcinoma in the upper urinary tract. A 69-year-old woman, who complained of gross hematuria and intermittent left flank dull pain underwent nephrectomy with the clinical diagnosis of papillary urothelial carcinomas in the left upper urinary tract according to positive split urine cytology and tumorous filling defects of contrast media by the abdominal CT scan. Pathological diagnosis was squamous metaplasia and concomitant foreign body granuloma. Those changes were judged due to a tiny calculus in the ureter. Our presented case implies that a tiny calculus can cause the metaplastic change in the urothelial epithelium and the combination of radiographical and cytological diagnoses would not be enough to lead the correct diagnosis and the definitive surgical treatment against protruding lesions in the upper urinary tract requires more reliable diagnostic modalities.

Aged↗
PubMed2003

Attenuation of heart failure due to coronary stenosis by ACE inhibitor and angiotensin receptor blocker.

It is not known how the angiotensin-converting enzyme (ACE) inhibitor and angiotensin II receptor blocker (ARB) attenuate heart failure (HF) in viable ischemic hearts. To assess HF in a rat coronary stenosis (CS) model, we administered vehicle and quinapril or candesartan (or both) orally for 12 wk. Compared with the sham group, the vehicle group showed impaired myocardial perfusion, impaired coronary endothelial nitric oxide (NO) function in vitro, exhausted myocardial mitochondrial respiration, larger left ventricular (LV) dimensions and lower ejection fraction, lower LV rate of pressure development over time (dP/dt), lower slopes of LV end-systolic pressure-dimension relations (ESPDRs), and increased myocardial fibrosis. Treatment with quinapril or candesartan ameliorated these parameters without modifying the epicardial CS severity. Moreover, their combination maintained similar myocardial perfusion, despite a trend toward lower blood pressure, and showed distinctive neurohumoral modulation, normalized mitochondrial respiration, and increased ESPDR slopes. Thus improved myocardial blood flow and coronary flow reserve by quinapril or candesartan are the key to alleviate CS-induced HF, and their combination may have a therapeutic significance partly through ameliorated mitochondrial respiration and improved LV systolic function.

Anesthesia↗
PubMed2003

A rapid biosensor chip assay for measuring of telomerase activity using surface plasmon resonance.

Considerable interest has been focused on telomerase because of its potential use in assays for cancer diagnosis, and for anti-telomerase drugs as a strategy for cancer chemotherapy. A number of assays based on the polymerase chain reaction (PCR) have been developed for evaluation of telomerase activity. To overcome the disadvantages of the conventional telomerase assay [telomeric repeat amplification protocol (TRAP)] related to PCR artifacts and troublesome post-PCR procedures, we have developed a telomeric repeat elongation (TRE) assay which directly measures telomerase activity as the telomeric elongation rate by biosensor technology using surface plasmon resonance (SPR). 5'-Biotinylated oligomers containing telomeric repeats were immobilized on streptavidin-pretreated dextran sensor surfaces in situ using the BIACORE apparatus. Subsequently, the oligomers associated with the telomerase extracts were elongated in the BIACORE apparatus. The rate of TRE was calculated by measuring the SPR signals. We examined elongation rates by the TRE assay in 18 cancer and three normal human fibroblast cell lines, and 12 human primary carcinomas and matching normal tissues. The elongation rates increased in a concentration- and time-dependent manner. Those of cancer cells were two to 10 times higher than fibroblast cell lines and normal tissues. Telomerase activities and its inhibitory effects of anti-telomerase agents as measured by both the TRE and TRAP assays showed a good correlation. Our assay allows precise quantitative comparison of a wide range of human cells from somatic cells to carcinoma cells. TRE assay is suitable for practical use in the assessment of telomerase activity in preclinical and clinical trials of telomerase-based therapies, because of its reproducibility, rapidity and simplicity.

Cell Line↗
PubMed2003

Evaluation of malignancy using Ki-67 labeling index for gastric stromal tumor.

BACKGROUND: Assessment of malignant potential in gastrointestinal stromal tumors (GISTs) is still problematic. The maximum tumor diameter and the mitotic index are generally used as an index of malignancy of GISTs. The Ki-67 labeling index has recently been used as an index of cell growth, and the prognosis of GISTs was reported to be significantly poor when the value of this index was 10% or higher. METHODS: Clinicopathological and immunohistological factors were analyzed in 15 patients who underwent surgical resection of gastric stromal tumors at our department between April 1997 and July 2002. The patients were divided into "metastasis/recurrence" and "benign" groups. Also, the relationship of changes in the Ki-67 labeling index to the degree of malignancy in recurrent lesions was assessed in an 84-year-old woman who underwent five reoperations because of recurrences in the peritoneum. RESULTS: Significant differences were noted between the metastasis/recurrence and benign groups in relation to the mean maximum tumor diameter (186.7 +/- 80.8 mm vs 41.3 +/- 22.9 mm), mitotic index (88.3 +/- 5.0/50 high-power fields [HPF] vs 3.0 +/- 2.9/50 HPF), and the Ki-67 labeling index (11.4 +/- 2.5% vs 0.01 +/- 0.51%). In the patient who had metastasis to the liver 3.5 years after initial operation and underwent five reoperations before death, the intervals until detection of recurrence tended to be shortened gradually. The Ki-67 labeling index varied with each operation, and tended to be higher at the time of reoperations than at the initial operation. CONCLUSION: The maximum tumor diameter, mitotic index, and Ki-67 labeling index were useful as an index of malignancy for gastric stromal tumor. The efficacy of surgical resection alone may be insufficient in patients with disseminated metastasis to the peritoneum.

Aged↗
PubMed2003

Unilateral renal cortical necrosis with contralateral hydronephrosis after surgery for uterus carcinoma.

Renal cortical necrosis (RCN) represents a rare cause of acute renal failure that is characterized by necrosis of the renal cortex with sparing of the medulla. Most previous RCN cases reported have been bilateral and have occurred in pregnancy. Unilateral RCN is a quite rare disorder. Here, we report a case of unilateral RCN with contralateral hydronephrosis after surgery for uterus carcinoma. In this patient it seems that hydronephrosis had been present before RCN occurrence. It is suggested that ureteric obstruction protects against RCN development.

Adenocarcinoma↗
PubMed2002

31P NMR quantification and monophasic solvent purification of human and bovine lens phospholipids.

Most lipid extraction procedures [Folch, J., Lees, M., and Sloane-Stanley, G.H. (1957) A Simple Method for the Isolation and Purification of Total Lipids from Animal Tissues, J. Biol. Chem. 226, 497-509; Bligh, E.G., and Dyer, W.J. (1959) A Rapid Method of Total Lipid Extraction and Purification, Can. J. Biochem. Physiol. 37, 911-917] employ biphasic solvent mixtures designed to dissolve the lipids in an organic phase and remove impurities in an aqueous phase. However, when applying these protocols to biological matrices such as that of the ocular lens, the formation of an emulsion layer between the organic and aqueous phases causes poor reproducibility in extraction yields and gives only a small amount of the lipid-containing chloroform phase. In this study, we quantified phospholipids at each step of the Folch et al. extraction protocol and compared the yield of human and bovine lens phospholipids obtained by the Folch-based approach and a novel monophasic methanol extraction method designed to circumvent the problems associated with biphasic extraction protocols. A monophasic methanol extraction coupled with 31P NMR spectroscopy was found to be the simplest, quickest, and most effective method for quantifying the phospholipid content of the lens.

2-Propanol↗