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Biomedical subjects

T Nakano

Publications and source records attributed to T Nakano.

At least 145 records · Page 8Linked to original sources
PubMed2001

High expression of CD34-positive sinusoidal endothelial cells is a risk factor for hepatocellular carcinoma in patients with HCV-associated chronic liver diseases.

CD34 has been widely used for the assessment of sinusoid-like neoangiogenesis in hepatocellular carcinoma (HCC). Recently, it was demonstrated that CD34-positive cells isolated from human peripheral blood differentiate into endothelial cells and contribute to neoangiogenesis in adults. We investigated the localization and the substantial role of CD34-positive endothelial cells in the liver with hepatitis C virus (HCV)--associated chronic liver diseases. Liver tissue sections obtained by biopsy from 56 patients with HCV-associated chronic liver diseases by were examined immunohistochemically using anti-CD34, anti-von Willebrand factor (vWF), and anti-vascular endothelial growth factor (VEGF) antibodies. CD34 was stained in the sinusoid, showing dotty, linear, semicircular, or circular patterns. However, sinusoidal expression of vWF was not substantially identified in the same specimens, indicating the existence of sinusoidal CD34-positive but vWF-negative endothelial cells. We classified these cells as CD34 LI and found that CD34 LI was correlated with the expression of VEGF. Among 34 patients with advanced-stage disease, the cumulative incidence of HCC was significantly higher in patients with CD34 LI >or= 12 (n = 16) than in those with CD34 LI < 12 (n = 18; P = .009). Moreover, among several clinicopathologic risk factors, CD34 LI could be recognized as an independently significant factor for development of HCC (relative risk, 7.36; P = .019). We conclude that CD34-positive endothelial cells are regulated by several factors, such as VEGF, and might play a substantial role in hepatocarcinogenesis. Furthermore, high expression of CD34-positive sinusoidal endothelial cells is a risk factor for HCC in patients with HCV-associated chronic liver diseases.

Adult↗
PubMed2001

Stimulation of arterial smooth muscle cell proliferation by remnant lipoprotein particles isolated by immuno-affinity chromatography with anti-apo A-I and anti-apo B-100.

Postprandial lipidemia, characterized by high plasma triglyceride-rich lipoprotein remnants, is associated with atherosclerosis. It has also been known that proliferation of vascular smooth muscle cells is crucial for the development of atherosclerosis. In this study, we investigated the direct effect of remnant lipoprotein particles, which consist of chylomicron remnants and very low density lipoprotein remnants, on vascular smooth muscle cell proliferation. Blood was collected from six patients with postprandial lipidemia two hours after their usual meal. Remnant lipoprotein particles were isolated from plasma by immuno-affinity chromatography containing two monoclonal antibodies, anti-apo A-I (H-12) and anti-apo B-100 (JI-H). Remnant lipoprotein particles, as well as betaVLDL, significantly stimulated the proliferation of porcine coronary artery smooth muscle cells in a concentration-dependent manner, whereas very low density lipoprotein (d < 1.006) was virtually ineffective. These observations are consistent with recent reports that triglyceride-rich lipoprotein remnants, which are rich in apo E as well, are atherogenic.

Animals↗
PubMed2001

Prospective study of laparoscopic findings with regard to the development of hepatocellular carcinoma in patients with hepatitis C virus-associated cirrhosis.

BACKGROUND: The laparoscopic findings of hepatocarcinogenesis are not well defined. The purpose of this prospective study was to evaluate the predictive value of laparoscopic findings with regard to the development of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-associated cirrhosis. METHODS: One hundred nineteen patients with HCV-associated cirrhosis who underwent laparoscopy were enrolled in this study. Ten laparoscopic variables, including degree of development and size of regenerating nodules, irregularity of regenerating nodules, and size of both hepatic lobes, were measured. The predictive value of each finding for the development of HCC was investigated by using univariate and multivariate analyses. RESULTS: HCC developed in a total of 42 of the 119 patients (35.3%) during a mean follow-up period of 62.9 months. The degree of regenerating nodules, the presence of irregular regenerative nodules, and atrophic right lobe were significant predictive factors for HCC with univariate analysis. In particular, 67.1% of patients with irregular regenerative nodules had HCC develop within 5 years. Multivariate analysis revealed that irregular regenerative nodules (relative risk 6.32, p = 0.012), the degree of regenerative nodules (relative risk 4.78, p = 0.029), and atrophic right lobe (relative risk 3.87, p = 0.048) were independent predictive factors. CONCLUSIONS: Morphologic observation of the liver surface by laparoscopy is important and provides information on factors that are statistically significant early predictors of the development of HCC.

Adult↗
PubMed2001

Inhibition by combined therapy with ticlopidine and aspirin of enhanced platelet aggregation during physical exercise in patients with coronary artery disease.

BACKGROUND: Strenuous exercise can be a major trigger for coronary thrombosis and it enhances platelet aggregation. METHODS: We evaluated the effect of antiplatelet therapy on shear stress-induced platelet aggregation (SIPA), in addition to agonist-induced aggregation, before and immediately after ergometer exercise in patients with stable coronary artery diseases (CAD). Forty-eight patients with stable CAD were randomly distributed into 3 groups: no antiplatelet drug (patient control, n = 16), aspirin (ASA) monotherapy (n = 16), and combined therapy with ticlopidine (TIC) and ASA (n = 16). RESULTS: There were significant increases in not only adenosine phosphate (ADP)- and collagen-induced platelet aggregation but also in SIPA during exercise by the patient control group. ASA monotherapy did not attenuate the enhanced ADP-induced aggregation nor SIPA. Combined ASA + TIC therapy significantly inhibited SIPA as well as ADP-induced aggregation both before and after exercise. Significant increases in levels of plasma von Willebrand factor (vWF) occurred during exercise, and these antiplatelet therapies had no apparent effect on increased vWF levels during exercise. Exercise induced a significant increase in the plasma thrombin-antithrombin III complex level with no significant changes in the level of plasmin-plasmin inhibitor complex level in all 3 groups. CONCLUSIONS: Combined therapy with ASA + TIC effectively inhibited increased platelet aggregability in response to acute exercise, with no effects on coagulant or fibrinolytic potentials in patients with CAD. The data suggest that TIC combined with ASA may be superior to ASA alone in preventing acute coronary events during exercise in patients with coronary atherosclerotic disease.

Adenine Nucleotides↗
PubMed2001

A case report of early idiopathic portal hypertension.

We report herein a case (46 years, female) of very early idiopathic portal hypertension. During an examination for in situ uterine cervical cancer, splenomegaly and hypersplenism were incidentally found. CT and MRI showed a nonatrophic liver with dilated portal veins and marked splenomegaly. The portal venous blood flow was increased, while portal venous blood pressure was not high. The spleen (1,220 g) showed hyperplasia of white pulp and congestion. The lobular architecture of the liver was well-preserved, and the subcapsular regions were not atrophic or dropped out. The portal tracts were not fibrotic, and portal veins were neither stenotic nor sclerotic. Instead, lymphoid cell infiltrations were found in about half the portal tracts, and there was subendothelial mononuclear cell infiltration of small portal vein branches. The hepatic lobules showed non-specific reactive change. This case suggests that early hepatic changes recognizable histologically in this disease are lymphoid cell infiltration of the portal tract and of subendothelial regions of portal vein branches, and nonspecific lobular hepatitis. These hepatic changes, as well as marked splenomegaly, may represent an altered immunophenomenon of this disease.

Carcinoma in Situ↗
PubMed2001

The combined use of US and MR imaging for the diagnosis of masses in the parotid region.

PURPOSE: To evaluate the usefulness of the combination of the two non-invasive modalities US and MR imaging to diagnose masses in the parotid region. MATERIAL AND METHODS: The US and MR findings of 21 patients with parotid masses were analyzed retrospectively by two radiologists without any clinical or histopathological information. The specific points evaluated were location, shape, margin, internal architecture, and intensity level on both US and MR, posterior echo enhancement on US, and capsule-like lining of the tumor on MR. RESULTS: The findings concerning the shape and margin on US and MR were in fairly good agreement. Concerning the findings of the internal architecture, US could reveal the minute structures of the tumor while MR demonstrated differences in the signal intensities of histological tissue types of the various tumors. The posterior echo enhancement on US and the capsule-like lining on MR of the tumors were also useful for the diagnosis. CONCLUSION: Our results suggest that the combination of US and MR is useful for examining soft tissue masses in the parotid region to make a more accurate diagnosis, and not just differentiate malignant lesions from those which are benign.

Adolescent↗
PubMed2001

Assessment of coronary flow velocity reserve using fast velocity-encoded cine MRI for noninvasive detection of restenosis after coronary stent implantation.

PURPOSE: Serial change of the coronary flow velocity reserve was evaluated with fast velocity-encoded cine magnetic resonance imaging (MRI) for noninvasive detection of restenosis after coronary stent implantation. METHOD: In total, 60 MRI flow studies were performed in 10 patients with coronary artery disease who undersvent elective successful stent implantation to the lesion in the proximal left anterior descending artery. Flow velocities in the segment that was distal to the stent were measured before and after intravenous injection of dipyridamole. MRI measurements of coronary flow velocity reserve were repeated every 4 weeks for 6 months, and follow-up angiography was performed 6 months after the procedure. RESULTS: In patients without restenosis (n = 7, % diameter stenosis: 27.8%+/-7.1) at follow-up angiography, the coronary flow velocity reserve remained normal during the 6-month follow-up time. The flow velocity reserve was 2.31+/-0.30 at 1 month and 2.52+/-0.25 at 6 months after stent implantation (p = NS). In contrast, the coronary flow velocity reserve showed a significant decrease after 4 months in patients with restenosis (n = 3, % diameter stenosis: 66.3%+/-8.1) at follow-up angiography. The flow velocity reserve was 2.26+/-0.49 at 1 month and 1.52+/-0.09 at 6 months after stent implantation (p < 0.05). CONCLUSION: Fast velocity-encoded cine MRI is a technique that shows promise in providing non-invasive detection of restenosis of coronary stent implantation.

Adult↗
PubMed2001

Simultaneous determination of gold and copper by reversed-phase high-performance liquid chromatography using online column enrichment as their syn-phenyl-2-pyridylketoximate chelates.

Gold and copper ions react with syn-phenyl-2-pyridylketoxime (PPKO) at 40 degrees C to form neutral chelates. Metal-PPKO chelates subsequently become preconcentrated on a minicolumn packed with a divinylbenzene-methacrylate copolymer. By switching the valve, these chelates are separated on the silica-based phenyl column and detected with a photometric detector. These processes occur automatically except for chelation. The results of the chelation, preconcentration, and separation conditions studies are presented. Calibration curves for Au and Cu ions are linear from nanograms per milliliter (parts per billion) to micrograms per milliliter (parts per million) in the original solution. The precision for 0.5-ppm standards of Au and Cu is 2.1 and 0.9 relative standard deviation (%), respectively. The accuracy of the present method is verified for Au and Cu based on the analysis of a standard alloy of the National Institute of Standards and Technology (NIST). The limits of detection for Au and Cu are 16.7 and 0.6 ppb, respectively. The effects of foreign ions on the determination of Au and Cu are discussed.

Journal Article↗
PubMed2001

Psychiatric disorders in cancer patients: descriptive analysis of 1721 psychiatric referrals at two Japanese cancer center hospitals.

BACKGROUND: Although a diagnosis of cancer today may no longer be considered to be the equivalent of a death sentence, many previous studies in Western countries have revealed that such a diagnosis places many kinds of emotional burden on a patient. However, few studies have focused on the nature of psychiatric disorders in Japanese cancer patients. METHODS: We investigated the characteristics, reason for psychiatric consultation and psychiatric diagnosis of cancer patients by analyzing the database of patients referred to the Psychiatry Divisions at the National Cancer Center Hospital and the National Cancer Center Hospital East, Japan. RESULTS: Among a total of 1721 referrals, most of the cancer patients (78%) were inpatients. Patients with lung cancer (19%) were the most common, followed by patients with breast cancer (13%) and with head and neck cancer (10%). More than half of the patients had recurrent and/or metastatic cancer and 60% of the patients had pain. The most common reason for the consultation was psychiatric evaluation (35%), followed by sleep disorders (19%), anxiety or fear (18%) and depression (18%). Regarding the psychiatric diagnosis, adjustment disorders were the most common (34%), followed by delirium (17%) and major depression (14%). The diagnosis of cancer had been disclosed to more than 99% of the patients. CONCLUSION: The common psychiatric disorders observed in Japanese cancer patients were similar to those in the Western countries provided the cancer diagnosis is disclosed.

Adolescent↗
PubMed2001

Mucinous adenocarcinoma of Bartholin gland treated with radiation therapy: a case report.

Adenocarcinoma of Bartholin gland is a very rare disease and its molecular pathological features are poorly delineated. A 92-year-old woman with mucinous adenocarcinoma of Bartholin gland with metastasis to the right inguinal lymph node was treated with radiation therapy alone. Despite intensive radiation therapy, the tumor was locally recurrent and the patient died 10 months after radiation therapy. We searched for the presence of human papillomavirus 16 and 18 DNA and the expression of p53 protein, CA19-9, CEA and MIB-1 antigen. Immunohistochemical study showed that mucinous adenocarcinoma of Bartholin gland produced CA19-9 and CEA.

Adenocarcinoma, Mucinous↗
PubMed2001

An improved procedure of electron microscopic in situ hybridization for detecting adenovirus DNA.

Electron microscopic in situ hybridization (EM-ISH) is a useful method in determining the localization of a specific nucleic acid at the ultrastructural level. Since the EM-ISH protocol includes many steps, no standard protocol for EM-ISH is available yet. In this study, we optimized quantitatively the critical conditions with respect to embedding resin, nucleic acid labeling and hybridization reaction time, by using adenovirus-infected cells as the indicator cells. The optimal detection of an adenovirus-specific nucleic acid was obtained by overnight hybridization reaction on sections embedded in Lowicryl K4M resin. Random-primed-labeled probes improved the reactivity. At least 60% of virus particles in paracrystalline arrays was found to contain viral DNA. These arrays in adenovirus-infected cells are useful in evaluating quantitatively the efficiency of protocols of EM-ISH.

Adenoviridae↗
PubMed2001

Adduct formation between oxanine and amine derivatives.

Oxanine (Oxa) is a major guanine lesion produced by nitric oxide (NO) under aerobic conditions. To elucidate the genotoxic mechanism of Oxa, this lesion was site-specifically incorporated into an oligonucleotide and allowed to react with cellular amines. Analysis of the reaction product revealed that Oxa formed adducts with spermidine and lysine, suggesting a novel genotoxic mechanism associated with NO-induced DNA damage.

Amines↗
PubMed2001

241Am as a metabolic tracer for inhaled plutonium nitrate in external chest counting.

The plutonium (Pu) treated in the nuclear fuel cycle is usually accompanied by 241Am produced from 241Pu by beta disintegration, which emits gamma rays of 60 keV with the emission rate of 0.36, being more penetrating than the L X rays from Pu. The 241Am could imprve the detection limit of chest counting of Pu, if it was being used as a metabolic tracer for Pu in lungs. Young adult male Wistar rats were exposed to polydisperse aerosols of Pu(NO3)4 with 0.6 microm in activity median aerodynamic diameter. They were periodically killed and the radioactivity of 241Am was cleared from the lungs at almost the same rate as the Pu at least for half a year post-inhalation, which proved the validity of 241Am as a metabolic tracer for inhaled Pu nitrate in external chest counting.

Aerosols↗
PubMed2001

Extraction of glycosaminoglycans from chicken eggshell.

The objectives of this study were to analyze glycosaminoglycan (GAG) and mineral composition in the chicken eggshell. Eggshells were decalcified with acetic acid, and GAG was extracted from the decalcified shell by digestion with papain. The eggshell contained an average of 0.024% of its dry weight as uronic acid, a carbohydrate moiety of GAG. The eggshell GAG consisted of approximately 48% hyaluronic acid and and 52% galactosaminoglycan. In the latter, chondroitin sulfate-dermatan sulfate copolymers were the major galactosaminoglycans with dermatan sulfate disaccharide as a relatively minor component. The inorganic material recovered after decalcification accounted for approximately 140% of dry weight of the eggshell and contained 24.11% calcium, 0.04% phosphorous, and 0.23% magnesium, with an undetectable amount of nitrogen.

Acetates↗
PubMed2001

Light-use properties in two sun-adapted shrubs with contrasting canopy structures.

We investigated the impact of high solar irradiance and elevated temperature on carbon gain by two, co-occurring, sun-adapted, dwarf shrub species, Planchonella obovata var. dubia (Koidz.) Hatusima and Hibiscus glaber Matsumura, growing on sun-exposed ridges in the Bonin Islands, in the subtropical Pacific Ocean. Planchonella had steeply inclined, longer lived, sclerophyllous leaves, whereas Hibiscus has thinner, more horizontally oriented, and shorter lived leaves. We tested the hypothesis that leaf physiological tolerance to high light is lower in Planchonella than in Hibiscus. Under relatively high irradiances (photosynthetic photon flux density, PPFD, > 500 micromol m(-2) s(-1)), net photosynthetic rate (P(n)) was about 8.0 and 0.4 micromol m(-2) s(-1) in mature and young leaves of Planchonella, and about 12.4 and 10.3 micromol m(-2) s(-1) in mature and young leaves of Hibiscus, respectively. Both P(n) and photosystem II (PSII) quantum yield at a given PPFD were lower in Planchonella than in Hibiscus, whereas non-photochemical quenching (NPQ) at a given PPFD was higher in Planchonella. When leaf discs were exposed to high light (1900 micromol m(-2) s(-1) PPFD) at 37, 40 or 43 degrees C for 3 h, the recovery of PSII quantum yield (F(v)/F(m)) in the following 60-min dark period was slower in Planchonella than in Hibiscus, indicating that the ability of PSII to tolerate high light and high temperature was less in Planchonella than in Hibiscus. We postulate that there is a linkage between leaf display and leaf photochemical ability in sun-adapted shrub species.

Magnoliopsida↗