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Biomedical subjects

H Yamaguchi

Publications and source records attributed to H Yamaguchi.

At least 37 records · Page 2Linked to original sources

The Japanese integrated staging score using liver damage grade for hepatocellular carcinoma in patients after hepatectomy.

AIMS: The new Japanese staging system for hepatocellular carcinoma (HCC), the Japan integrated staging (JIS) score, accounts for both Child-Pugh classification and Japan tumour node metastasis (TNM) staging. However, in HCC patients who undergo hepatectomy, liver function is relatively good and a better prognostic classification of hepatic function is necessary. METHODS: The present study was designed to analyse the modified JIS score using liver damage grade by the Liver Cancer Study Group of Japan instead of the Child-Pugh classification (using the category indocyanine green retention rate at 15 min [ICG(R15)] instead of encephalopathy), and to compare the Japan TNM stage in 101 patients who underwent resection of HCC. RESULTS: The liver damage grade showed significantly better discrimination of disease-free and overall survival than did the Child-Pugh classification. The modified JIS score system showed significant differences of disease-free and overall survivals in each score and this system was superior for discriminating survivals compared with the TNM staging. CONCLUSIONS: The combined staging system of hepatic function, particularly ICG(R15), and tumour stage provides a better prediction of prognosis. The JIS score using the liver damage grade was a useful predictor of prognosis of HCC patients who underwent hepatic resection.

Adult↗

Phylogenetic relationships among medically important yeasts based on sequences of mitochondrial large subunit ribosomal RNA gene.

Sequences of the mitochondrial large subunit ribosomal RNA (mtLsurRNA) gene of medically important yeasts were analysed. Sixteen strains of eight species including two varieties were subjected to sequencing. Sequencing enabled us to recognize the differences between all the species and varieties. Alignment analysis revealed that these sequences consisted of three clusters: the Candida albicans group, the C. glabrata group, and the basidiomycetous group. It is possible, therefore, that the mtLsurRNA gene is one of the targets not only for species identification but also for phylogenetic analysis of closely related yeasts. The dendrogram of each group, obtained from this gene, supports the previous study of yeasts based upon the chromosomal genes.

Base Sequence↗

A case of Kallmann syndrome associated with Dandy-Walker malformation.

A 19-year-old man was admitted to our hospital for delayed puberty. At birth, he had macrocephalia and showed delayed physical and mental development. At 9 years of age, right cryptorchism was diagnosed. His parents had noticed that he could not recognize any smells since his infancy. Physical examination on admission revealed ocular hypertelorism, high myopia, high arched palate, and intermittent external strabismus. Sense of smell was scaled out by olfactometry. External genitalia were infantile. Neurological examination showed on IQ of 83, and mild truncal ataxia. Magnetic resonance imaging (MRI) showed a cystic distension of the IV ventricle, partial aplasia of the cerebellar vermis, elevation of the tentorium cerebelli, enlargement of the III ventricle, and agenesis of the corpus callosum. These findings revealed that the patient had Dandy-Walker malformation. The basal FSH, LH, and testosterone levels were all low compared with normal adult reference values. The serial LH-RH provocation tests showed stepwise LH and FSH elevation. After the fifth day of LH-RH administration, both LH and FSH responses clearly improved. Olfactory tracts were defective in MRI findings. These findings were consistent with hypogonadotropic hypogonadism of hypothalamic origin with anosmia, and the patient was therefore diagnosed with Kallmann syndrome. Sequence analysis of the KAL1 gene showed no mutation in the coding region. To our knowledge, this is the first case report of the coexistence of Kallmann syndrome and Dandy-Walker malformation in the same patient.

Adult↗

Near-triploidy and near-tetraploidy in hematological malignancies and mutation of the p53 gene.

Hyperdiploidy of > or =58 chromosomes is reported in 0.5-3% of hematological malignancies, but reports of near-triploidy (58-80 chromosomes) and near-tetraploidy (81-103 chromosomes), are few. We examined these chromosome abnormalities and analyzed the relationship with the mutation of the p53 gene. Thirty-one of 979 adult patients (3.2%) with hematological malignancies were identified as having near-triploid or near-tetraploid (tri-/tetraploid) chromosomes. These included 11 with B-cell neoplasms, seven with Hodgkin's lymphoma, five with T-cell neoplasms, four with myelodysplastic syndromes and four with acute myeloid leukemias. All patients had concurrent complex chromosome aberrations. Deletion of one allele of the p53 gene was found in two patients and a point mutation of the p53 gene was detected in five patients. Although abnormalities of the p53 gene have been reported in about 10% of hematological malignancies, these were found in seven of 31 (23%) patients with tri-/tetraploidy. These findings suggest that the abnormality of the p53 gene may be closely related with tri-/tetraploidy. The four myelodysplastic syndrome (MDS) patients with tri-/tetraploidy had a significantly worse prognosis than those with diploid cytogenetics (n = 35; P < 0.002). In B-cell neoplasms (n = 3), triploidy was associated with a worse prognosis than tetraploidy (n = 8) and diploidy (n = 130; P < 0.02).

Adult↗

Expression of glucose transporter 5 by microglia in human gliomas.

Our previous studies indicate that glucose transporter 5 (GLUT5) is a microglial marker in routine paraffin sections, and is rarely present in monocytes/macrophages of the peripheral organs. We examined the expression of GLUT5 in 91 cases of human gliomas to characterize the microglial phenotype in glioma tissues. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections using such antibodies as a GLUT5 antibody, two markers for activated microglia: major histocompatibility complex (MHC) class II Ag and macrophage scavenger receptor class A (MSR-A), and MIB-1 antibody. The immunoreactivity of GLUT5 was present in three microglial phenotypes: ramified (resting), activated, and ameboid (macrophagic) microglia in most of the cases. A double-labelling study of astrocytic tumours using GLUT5 and MIB-1 antibodies demonstrated a proportion of proliferating microglia. However, no morphological difference between MIB-1-positive, microglial cells and MIB-1-negative, microglial cells was found. The number of GLUT5-positive microglia was significantly (P < 0.001) higher in astrocytic tumours than in oligodendroglial tumours. Many GLUT5-positive microglia (up to 52% in total cells) were often observed in pilocytic astrocytomas, where microglial cells were predominantly ramified, and the number of MHC class II- or MSR-A-positive microglia was less than GLUT5-positive microglia. Thus, the present study indicated that intrinsic microglia can be a source of microglia/macrophages cell populations in astrocytic tumours, and that pilocytic astrocytomas often have a high proportion of microglial cells with mild activation.

Blotting, Western↗

Direct measurement of transition frequencies in isolated pHe+ atoms, and new CPT-violation limits on the antiproton charge and mass.

A radio frequency quadrupole decelerator and achromatic momentum analyzer were used to decelerate antiprotons and produce p4He+ and p3He+ atoms in ultra-low-density targets, where collision-induced shifts of the atomic transition frequencies were negligible. The frequencies at near-vacuo conditions were measured by laser spectroscopy to fractional precisions of (6-19) x 10(-8). By comparing these with QED calculations and the antiproton cyclotron frequency, we set a new limit of 1 x 10(-8) on possible differences between the antiproton and proton charges and masses.

Journal Article↗

High resolution spectroscopy of the 12Lambda B hypernucleus produced by the (e,e'K+) reaction.

High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique.

Journal Article↗

Gasless, video endoscopic transanal excision for carcinoid and laterally spreading tumors of the rectum.

BACKGROUND: The aim of this study is to determine whether gasless, video endoscopic transanal-rectal tumor excision (gasless VTEM) is a valid treatment for rectal carcinoid and laterally spreading tumors (LST). METHODS: Eighty-four patients with an adenoma, adenocarcinoma (Tis/T1), or carcinoid tumor of the rectum were divided into three groups: (i) LST ( n = 17 patients), (ii) carcinoid ( n = 11), and (iii) control with other types of tumors ( n = 56). RESULTS: The LST group had a longer median operating time than in the control group, whereas the carcinoid group had a shorter operating time. Two patients (11.7%) in LST group developed peritoneal entry during the operation, while 2 patients (3.6%) in the control group experienced postoperative complications. During a median follow-up length of 55.2 months, one patient in the LST group developed a recurrence. CONCLUSIONS: Gasless VTEM is a simple, minimally invasive procedure used to treat LST and carcinoid tumors of the rectum. However, resection for the LST group had a high risk of peritoneal entry during operation.

Adenocarcinoma↗

Cerebral blood flow index image as a simple indicator for the fate of acute ischemic lesion.

BACKGROUND AND PURPOSE: To evaluate the feasibility of utilizing cerebral blood flow (CBF) index images, we attempted to investigate 1) whether CBF index images can reveal the resulting infracted area, 2) whether the CBF index can correlate other modality (SPECT). METHODS: DWI and DPI were obtained in 17 patients within 12 hours of stroke onset and follow up MRI. On three DPI delivered images, namely relative regional cerebral blood volume (rrCBV), uncorrected mean transit time (MTTu) and CBF index images, correlations between initial lesion volume of and follow up infarction volume of three images and rCBF images delivered with singular value decomposition (SVD) methods were assessed. Then 99mTc-ECD SPECT was taken immediately after MRI to correlate to MRI data. RESULTS: Among the three images, lesion volume of CBF index images against follow up infarct volume had the highest correlation (r = 0.995) to a linear fit and the slope was closest to 1.0 (0.91) and had identical accuracy to the regression coefficient of rCBF images. CBF index well correlated to SPECT delivered CBF. CONCLUSION: CBF index images can accurately predict final infarct volume. Evaluating CBF index images together with DWI can guide the initial assessment in the acute stage of cerebral ischemia.

Acute Disease↗

Modified CLIP using PIVKA-II for evaluating prognosis after hepatectomy for hepatocellular carcinoma.

AIMS: The new staging system proposed by the Cancer of the Liver Italian Program (CLIP) for hepatocellular carcinoma (HCC) accounts for both liver dysfunction and tumour characteristics. The present study was designed to analyze UICC TNM stage, CLIP and modified CLIP in 91 patients who underwent hepatic resection for HCC. METHODS: In the modified CLIP, scoring of AFP was replaced by that of protein induced by vitamin K absence or antagonist II (PIVKA-II; predictive value, > or = 400 mAU/ml). RESULTS: After hepatic resection, 54 patients developed recurrent tumours. High PIVKA-II was a significant determinant of recurrence (p<0.05). However, a high score of the modified CLIP as well as those other staging systems did not correlate with tumour-recurrence rate. Univariate analysis showed that high TNM score, CLIP score and our modified CLIP score were significant predictors of poor prognosis. Multivariate Cox's analysis revealed that high PIVKA-II and high modified CLIP score were associated with higher risk for disease-free and overall survival as well as high TNM stage. CONCLUSIONS: Compared with the original CLIP, our modified CLIP was a better predictor of prognosis of HCC patients who underwent hepatic resection.

Adult↗

Biochemical markers of vasospastic coronary artery disease.

OBJECTIVE: The risk factors for vasospastic angina pectoris (VSA) have not yet been well defined. We compared the plasma levels of lipids, apo(lipo)proteins, remnants of triglyceride (TG)-rich lipoproteins, oxidized low density lipoprotein (Ox-LDL), cholesteryl ester transfer protein (CETP) [which transfers esterified cholesterol (EC) from HDL to TG-rich lipoproteins and reduces plasma HDL levels], high-sensitivity C-reactive protein (hs-CRP), homocysteine and plasminogen-activator inhibitor (PAI)-1 in background-matched groups of controls, and patients with VSA or coronary atherosclerotic disease (CAD) (n=50 subjects each). METHODS AND RESULTS: The cholesterol levels of remnant-like particles (RLP), which are equivalent to the remnants of TG-rich lipoproteins, were measured using a precipitation method. Ox-LDL, CETP and PAI-1 were measured by means of sandwich ELISA; hs-CRP by means of nephelometry; and homocysteine by means of HPLC. Plasma LDL-C levels were high only in the CAD group, and plasma apo E and PAI-1 levels were high only in the VSA group. The plasma levels of TG, apo CII and RLP-C were highest in the VSA group, followed by the CAD group. The plasma levels of apoB, apo CIII, Ox-LDL, CETP, hs-CRP and homocysteine were equally increased in both the VSA and CAD groups. The increases in plasma RLP-C, CETP, hs-CRP and homocysteine were not significantly different between stable and unstable states of angina pectoris in either the VSA or CAD group. CONCLUSION: The increases in plasma TG-rich lipoproteins and their remnants were more significant markers of VSA than of CAD. The increases in plasma CETP, Ox-LDL, hs-CRP and homocysteine were equally important markers of VAS and CAD.

Analysis of Variance↗

Chromosomal imbalances associated with acquired resistance to fluoropyrimidines in human colorectal cancer cells.

The chromosomal aberrations underlying the development of resistance to fluoropyrimidines have not yet been identified. To characterise the genomic changes that induce the development of resistance to fluoropyrimidines, we used comparative genomic hybridisation (CGH) to analyse and compare the parent DLD-1 human colorectal cancer cell line and two cell lines, DLD-1/5-FU and DLD-1/FdUrd, which were resistant to 5-fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd), respectively. Both resistant cell lines showed a genetic aberration derived from the parental cell line DLD-1. Losses of 3p and 3q were also detected as additional genetic changes in the two resistant cell lines. Both resistant cell lines showed decreased orotate phosphoribosyltransferase (OPRT) activity, which is associated with the activity of the uridine monophosphate (UMP) synthase gene (3q13). These results suggested that the loss of 3q might be a genetic change responsible for the decreased OPRT activity and fluoropyrimidine cytotoxic response in cancer cells. Amplification of 18p11.2-p11.3 containing the thymidine synthase (TS) gene (18p11.32) was observed only in the DLD-1/FdUrd-resistant cell line, which overexpresses TS. These findings suggested that 18p amplification represents a genetic change associated with the overexpression of the TS protein. Our results indicate that chromosomal aberrations identified by CGH could explain, at least in part, acquired fluoropyrimidine resistance.

Antimetabolites, Antineoplastic↗

A case of pulmonary aspergilloma molecular biological identification and typing of the isolates from antemortem sputa and autopsy fungus ball.

Filamentous fungi were isolated from antemortem sputum and an autopsy fungus ball of the lung in a case of aspergilloma. Both of the isolates were analyzed for the sequences of species or strain-specific nuclear ribosomal DNA (partial 28S and ITS1 regions), and were identified as Aspergillus fumigatus. The molecular biological technique saved time and is thought to be a powerful tool in the accurate diagnosis of pulmonary fungal infection to assure effective treatment.

Aspergillosis↗

An epidemiological and clinical study of untreated patients with tinea pedis within a company in Japan.

In this study, we investigated epidemiological and clinical aspects of dermatophyte foot infections among employees of one dairy product company located in Kanagawa prefecture in central Japan. Sixty-nine of 377 subjects were reported having "athlete's foot" in response to a simple questionnaire. A subsequent mycological examination revealed 41 untreated patients with tinea pedis and/or tinea unguium (89% of subjects examined) and the overall prevalence was estimated at 18%. Comparing severity scores of five clinical symptoms (itching, erythema, vesicles/pustules, erosion/maceration, and scales) between those untreated patients within the subjects and another group of patients who spontaneously attended dermatological clinics to treat tinea pedis, itching, erythema, and total score were significantly higher in the latter group.

Adult↗

Long-term outcomes of intragastric endoscopic mucosal resection using a modified buess technique for early gastric cancer.

BACKGROUND/AIMS: The aim of this study was to clarify long-term outcomes of endoscopic mucosal resection (EMR) using a modified Buess technique for mucosal gastric cancer. METHODS: The procedure included en bloc mucosal resection using a Buess-type rectoscope into the gastric lumen via a temporary gastrostomy under video camera guidance. We reviewed 5 patients who underwent this procedure between 1995 and 1997 with a single mucosal cancer of the stomach that was unsuitable for en bloc excision by endoscopic snare diathermy. RESULTS: All tumors were superficial elevated types (type 0-IIa) located in the middle third and posterior wall of the stomach. Median maximum tumor diameter was 2.2 (range 1.1-3.5) cm. There was no operative mortality. One patient developed a hemorrhagic gastric ulcer postoperatively. All tumors histologically showed curative potential of the mucosal resection without margin involvement. During a median follow-up period of 64 (50-77) months, none of the patients developed local recurrence. One patient had an early gastric cancer that metachronously developed at another stomach site. CONCLUSION: Intragastric EMR using a modified Buess technique appears to be a useful treatment for cure of mucosal gastric cancer for a limited group of patients unsuitable for complete en bloc excision by endoscopic snare diathermy.

Adenocarcinoma↗

Canine counterpart of senile dementia of the Alzheimer type: amyloid plaques near capillaries but lack of spatial relationship with activated microglia and macrophages.

Senile plaques and cerebrovascular amyloidosis are major histopathological lesions in the brains of aged dogs. Different types of amyloid beta protein (A beta) positive plaques are known: diffuse ones and neuritic plaques. Diffuse plaques may contain membrane-bound A beta and/or small amounts of amyloid fibrils. Neuritic plaques are cored plaques with clusters of amyloid fibrils and degenerating neurities. In human amyloid plaques, a pathogenetic role for microglia cells has been described. The aim of this investigation was to study microglia cells in relationship to canine plaques and to investigate the localisation of amyloid plaques in relationship to vasculature. The lesions were studied by hematoxylin and eosin Congo red staining and immunohistochemistry with anti-A beta for plaques, with Mac 387, anti lysozyme and a series of lectins for mononuclear cells, with anti von Willebrand Factor and Lycopersicon esculentum (tomato) lectin for the endothelium of brain capillaries. Diffuse A beta-positive plaques were found in dogs of 10.8 years and older, and cored A beta-positive plaques with birefringent amyloid in Congo red-stained sections in subjects of 15 years and older. Accumulation of microglia cells in relationship to the plaques was not obvious. With anti A beta 8-17 the distribution of the plaques in the cortical layers varied. The younger dogs had primarily diffuse plaques in the deeper layers of the cortical grey matter. The older dogs showed more cored plaques than diffuse plaques which were found throughout all cortical grey matter layers. With anti A beta x-42 more plaques were found positive, especially diffuse ones, whereas staining results of anti A beta x-40 were more confined to amyloid plaques and vascular amyloid. A close spatial relationship was found between the cored plaques and capillaries.

Aging↗

Hyperfine structure of antiprotonic helium revealed by a laser-microwave-laser resonance method.

Using a newly developed laser-microwave-laser resonance method, we observed a pair of microwave transitions between hyperfine levels of the (n,L)=(37,35) state of antiprotonic helium. This experiment confirms the quadruplet hyperfine structure arising from the interaction of the antiproton orbital angular momentum, the electron spin and the antiproton spin as predicted by Bakalov and Korobov. The measured frequencies of nu(+)(HF)=12.895 96+/-0.000 34 GHz and nu(-)(HF)=12.924 67+/-0.000 29 GHz agree with recent theoretical calculations on a level of 6x10(-5).

Journal Article↗

Human GLUT5 immunolabeling is useful for evaluating microglial status in neuropathological study using paraffin sections.

In neuropathological studies it is important to detect both resting and reactive microglia in paraffin sections. We examined the usefulness of human (h) GLUT5, a glucose transporter, as a microglial marker. We produced an hGLUT5 antibody against its C-terminal sequence and stained human brain tissue sections. The hGLUT5 antibody consistently stained microglia in cryostat sections. In paraffin sections fixed with formalin, paraformaldehyde or ethanol, both resting and reactive microglia were stained; the latter were stained more intensely than the former. The hGLUT5 and glial fibrillary acidic protein labeling did not overlap each other in double immunofluorescence analyses. Oligodendrocytes, perivascular cells, choroid plexus epithelium and ependymal cell were negative for hGLUT5. Even after 1-month fixation in formalin, the hGLUT5 antibody stained microglia well. Microwave pretreatment enhanced the immunoreactivity of hGLUT5. As compared with other microglial markers, KP-1, KiM1p, CR3.43 and RCA-1, the hGLUT5 antibody could be considered good morphological marker. hGLUT5 immunolabeling clearly showed the detailed microglial processes, whereas immunolabeling with Ki-M1P and KP-1 showed cytoplasmic granules, and it was difficult to trace the microglial processes. The hGLUT5 antibody stained both resting and reactive microglia, whereas CR3.43 stained only reactive microglia, and RCA-1 labeled microvessels more intensely than microglia. Thus, hGLUT5 is a marker that is suitable for routine histopathological staining procedures.

Adult↗