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Koichi Nakano

Publications and source records attributed to Koichi Nakano.

14 recordsLinked to original sources
PubMed2006

Multiple label-free detection of antigen-antibody reaction using localized surface plasmon resonance-based core-shell structured nanoparticle layer nanochip.

In this research, a localized surface plasmon resonance (LSPR)-based bioanalysis method for developing multiarray optical nanochip suitable for screening bimolecular interactions is described. LSPR-based label-free monitoring enables to solve the problems of conventional methods that require large sample volumes and time-consuming labeling procedures. We developed a multiarray LSPR-based nanochip for the label-free detection of proteins. The multiarray format was constructed by a core-shell-structured nanoparticle layer, which provided 300 nanospots on the sensing surface. Antibodies were immobilized onto the nanospots using their interaction with Protein A. The concentrations of antigens were determined from the peak absorption intensity of the LSPR spectra. We demonstrated the capability of the array measurement using immunoglobulins (IgA, IgD, IgG, IgM), C-reactive protein, and fibrinogen. The detection limit of our label-free method was 100 pg/mL. Our nanochip is readily transferable to monitor the interactions of other biomolecules, such as whole cells or receptors, with a massively parallel detection capability in a highly miniaturized package. We anticipate that the direct label-free optical immunoassay of proteins reported here will revolutionize clinical diagnosis and accelerate the development of hand-held and user-friendly point-of-care devices.

Antigen-Antibody Reactions↗
PubMed2005

Thyroid cancer with massive invasion into the neck and mediastinal great veins.

Papillary thyroid carcinoma with massive invasion into the great veins of the neck and mediastinum has rarely been reported and is thought to have a poor prognosis. Here we report successful management of a case of papillary thyroid carcinoma with extensive invasion into the left internal jugular vein, left brachiocephalic vein, and superior vena cava, followed by reconstruction of the superior vena cava using an artificial graft. The operation was conducted to prevent sudden death due to complete obstruction of venous flow, improve the patient's quality of life, and prolong survival. The patient has survived for more than two years after surgery, with good general condition.

Brachiocephalic Veins↗
PubMed2005

Diagnostic value of FDG PET and salivary gland scintigraphy for parotid tumors.

PURPOSE: The purpose of this study was to examine the diagnostic value of the combination of F-18 fluorodeoxyglucose (FDG) PET and Tc-99m pertechnetate salivary gland scintigraphy in parotid tumors. MATERIALS AND METHODS: Seventy-two patients with benign parotid gland tumors (n = 52), malignant parotid tumors (n = 12), and inflammation (n = 8) underwent both FDG PET and salivary gland scintigraphy within 1 week, and 66 of the patients also underwent gallium scintigraphy. All patients were negative on their first fine-needle aspiration (FNA). RESULTS: Malignant parotid tumors showed significantly higher FDG uptake (standard uptake values [SUVs]) than both benign tumors and inflammation, except in Warthin's tumor (5.82 +/- 3.95 vs. 2.07 +/- 1.33; P <0.01). Although the SUV values of Warthin's tumor and malignant parotid tumors overlapped somewhat, Warthin's tumor did demonstrate increased radiotracer uptake, and it was reliably distinguished from other parotid gland tumors by the use of salivary gland scintigraphy. Considering a SUV value >3 as being positive for malignancy and excluding Warthin's tumor on the basis of salivary gland scintigraphy, sensitivity and specificity of FDG PET were 75% and 80%, respectively. These results were superior to those of gallium scintigraphy (58% and 72%, respectively). CONCLUSIONS: Although the diagnostic value of FDG PET in the differentiation of malignant from benign parotid gland tumors was limited because of the high FDG uptake in some benign tumors, and particularly pleomorphic adenomas, combining salivary gland scintigraphy with FDG PET may help to negate this drawback, and this combination may be a more promising approach for differentiation of various parotid gland tumors in patients compared with nondiagnostic needle aspiration.

Adolescent↗
PubMed2004

Mrp2 is involved in benzylpenicillin-induced choleresis.

Benzylpenicillin (PCG; 180 micromol/kg), a classic beta-lactam antibiotic, was intravenously given to Sprague-Dawley (SD) rats and multidrug resistance-associated protein 2 (Mrp2)-deficient Eisai hyperbilirubinemic rats (EHBR). A percentage of the [(3)H]PCG was excreted into the bile of the rats within 60 min (SD rats: 31.7% and EHBR: 4.3%). Remarkably, a transient increase in the bile flow ( approximately 2-fold) and a slight increase in the total biliary bilirubin excretion were observed in SD rats but not in the EHBR after PCG administration. This suggests that the biliary excretion of PCG and its choleretic effect are Mrp2-dependent. Positive correlations were observed between the biliary excretion rate of PCG and bile flow (r(2) = 0.768) and more remarkably between the biliary excretion rate of GSH and bile flow (r(2) = 0.968). No ATP-dependent uptake of [(3)H]PCG was observed in Mrp2-expressing Sf9 membrane vesicles, whereas other forms of Mrp2-substrate transport were stimulated in the presence of PCG. GSH efflux mediated by human MRP2 expressed in Madin-Darby canine kidney II cells was enhanced in the presence of PCG in a concentration-dependent manner. In conclusion, the choleretic effect of PCG is caused by the stimulation of biliary GSH efflux as well as the concentrative biliary excretion of PCG itself, both of which were Mrp2 dependent.

Animals↗
PubMed2003

Usefulness of diagnostic imaging in primary hyperparathyroidism.

BACKGROUND: In patients with primary hyperparathyroidism, prevention of urinary stone recurrence can be achieved by surgical removal of the enlarged parathyroid gland. To ensure the efficacy of surgery for primary hyperparathyroidism, preoperative localization of the enlarged gland is important. In the present study, usefulness of diagnostic imaging for localization of the enlarged gland was investigated in primary hyperparathyroidism. METHODS: We retrospectively examined the findings of imaging studies and clinical records in 79 patients (97 glands) who underwent surgical treatment for primary hyperparathyroidism at Chiba University Hospital between 1976 and 2000. The detection rates of accurate localization were investigated for imaging techniques, such as ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), thallium-201 and technetium-99m pertechnetate (Tl-Tc) subtraction scintigraphy and 99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy, and analysed in relation to the size and weight of the gland and pathological diagnosis. RESULTS: The detection rates by US, CT, MRI, Tl-Tc subtraction scintigraphy and MIBI scintigraphy were 70%, 67%, 73%, 38% and 78%, respectively. The overall detection rate changed from 50% to 88% before and after 1987. The detection rate of MIBI scintigraphy was superior to Tl-Tc subtraction scintigraphy. CONCLUSION: In primary hyperparathyroidism, improvement of accurate localization of an enlarged parathyroid gland was demonstrated along with recent advances in imaging techniques including MIBI scintigraphy.

Adenoma↗
PubMed2003

Impact of intranasal budesonide on immune inflammatory responses and epithelial remodeling in chronic upper airway inflammation.

BACKGROUND: Histologic and immunohistologic features of nasal polyps (NP) are similar to those observed in asthma, thus suggesting a similar immunopathology. OBJECTIVE: The primary objective of this study was to further understand the anti-inflammatory and immunoregulatory effects of locally delivered corticosteroids. To this end, the effect of intranasal budesonide on the expression of specific cytokines, lymphocyte subsets, and epithelial remodeling in this model of airway tissue inflammation were studied. METHODS: We used immunohistochemical techniques to examine nasal mucosae (NM) from healthy individuals and nasal polyp (NP) tissues from patients with nasal polyposis obtained before and after intranasal budesonide treatment. RESULTS: First, the density of CD8(+) cells was markedly increased in NP tissues after intranasal budesonide treatment from 16.1 +/- 8.4 (M +/- SEM) per mm(2) to 39.9 +/- 24.1. Second, the density of cells immunoreactive for IL-4, IL-5, IFN-gamma, IL-12, and TGF-beta in NP was significantly greater than in control NM tissues. The density of IL-4(+) and IL-5(+) cells in NP tissues significantly decreased after budesonide treatment from 40 +/- 12 to 17.8 +/- 8 and from 19.3 +/- 11 to 10.4 +/- 7, respectively. In contrast, the density of IFN-gamma(+) and IL-12(+) cells remained unchanged. In addition, we found that the density of TGF-beta(+) cells significantly increased after intranasal budesonide from 18 +/- 5 to 41 +/- 9. Third, damage to the entire length of the NP epithelium was quantified using a grading system. The epithelium of untreated NP was substantially damaged; remarkable epithelial restitution with no apparent changes in stromal collagen deposition was observed after intranasal budesonide treatment. CONCLUSIONS: These findings demonstrate that intranasal budesonide induced an increase in CD8 population and a selective regulatory effect on tissue cytokine expression. Furthermore, intranasal budesonide promoted epithelial remodeling. We hypothesize that these immunoregulatory and remodeling effects elicited by steroids might be, at least in part, mediated by the induction of TGF-beta.

Administration, Intranasal↗
PubMed2002

Interleukin-13 induces thymus and activation-regulated chemokine (CCL17) in human peripheral blood mononuclear cells.

BACKGROUND: In allergic inflammation involving allergic rhinitis, the predominance of Th(2) lymphocytes is one of the primary causal agents in promotion of the allergic condition. Thymus and activation-regulated chemokine (TARC/CCL17) is a recently identified chemokine that induces the development of Th(2) lymphocytes. One of the sources of TARC has been reported to be peripheral blood mononuclear cells (PBMCs). OBJECTIVE: We investigated TARC production from PBMCs by the stimulation of specific antigens and Th(2) type cytokines. METHOD: PBMCs were isolated from both allergic rhinitis patients and healthy volunteers. PBMCs were incubated with cytokine. TARC mRNA expression was examined by real time PCR methods and the amount of TARC production was examined by ELISA. RESULTS: IL-13 was found to be the most potent inducer for TARC mRNA expression and protein production in PBMCs. Furthermore, tumour necrosis factor alpha and IL-13 synergistically induce TARC. The amount of TARC from allergic rhinitis patients was significantly larger than that from healthy volunteers. Moreover, TARC was induced by a specific antigen, and was 35% inhibited by an anti-IL-13 neutralizing antibody. CONCLUSION: These results indicate that IL-13 is important in TARC mediated Th(2) lymphocytes infiltration in the nasal mucosa.

Adolescent↗
PubMed2002

The effect of Japanese cedar-specific immunotherapy on cytokine production in peripheral blood mononuclear cells.

The most common cause of seasonal allergic rhinitis in Japan is the Japanese cedar (JC). Recently, a pullulan-conjugated antigen (CS-560) has been developed to reduce adverse effects and to enhance the effect of JC-specific immunotherapy (IT). If the mechanism of IT can be fully elucidated and the treatment can be used safely and with specificity, IT should be reconsidered as a superior treatment for JC pollinosis. Thirteen patients with JC pollinosis who received IT were compared to 10 patients who did not receive IT. All patients were followed through two pollen seasons by means of allergy diaries. Peripheral blood mononuclear cells (PBMC) were collected before IT and just before each pollen season, and these were stimulated with pollen extract. The concentrations of IL-4, IL-5, IL-13 and IFN-gamma in the culture supernatants were determined using an ELISA. Furthermore, messenger (m)RNA expressions of IL-4 and IL-5 from cultured PBMC were also studied. As a result of the allergy diaries, we confirmed the clinical efficacy of CS-560. The symptom-medication scores were significantly decreased by IT. The levels of IL-4, IL-5 and IL-13 declined only in the IT group. However, the level of IFN-gamma did not change in either group. IL-4 and IL-5 mRNA expressions were inhibited in the IT group compared to that in the non-IT group. In conclusion, specific IT for JC pollinosis using CS-560 clearly modified cytokine expression by PBMC.

Adult↗
PubMedDate not supplied

Subcellular localization of phosducin in rod photoreceptors.

Phosducin (Pd) is a 28-kD phosphoprotein whose expression in retina appears limited to photoreceptor cells. Pd binds to the beta,gamma subunits of transducin (Gt). Their binding affinity is markedly diminished by Pd phosphorylation. While Pd has long been regarded as a candidate for the regulation of Gt, the molecular details of Pd function remain unclear. This gap in understanding is due in part to a lack of precise information concerning the total amount and subcellular localization of rod Pd. While earlier studies suggested that Pd was a rod outer segment (ROS) protein, recent findings have demonstrated that Pd is distributed throughout the rod. In this report, the subcellular distribution and amounts of rat Pd are quantified with immunogold electron microscopy. After light or dark adaptation, retinal tissues were fixed in situ and prepared for ultrathin sectioning and immunogold labeling. Pd concentrations were analyzed over the entire length of the rod. The highest Pd labeling densities were found in the rod synapse. Less intense Pd staining was observed in the ellipsoid and myoid regions, while minimal labeling densities were found in the ROS and the rod nucleus. In contrast with rod Gt, no evidence was found for light-dependent movement of Pd between inner and outer segments. There is a relative paucity of Pd in the ROS as compared with the large amounts of Gt found there. This does not support the earlier idea that Pd could modulate Gt activity by controlling its concentration. On the other hand, the presence of Pd in the nucleus is consistent with its possible role as a regulator of transcription. The functions of Pd in the ellipsoid and myoid regions remain unclear. The highest concentration of Pd was found at the rod synapse, consistent with a suggested role for Pd in the regulation of synaptic function.

Animals↗
PubMedDate not supplied

Inter- and intratumoral variability in magnetic resonance imaging of pleomorphic adenoma: an attempt to interpret the variable magnetic resonance findings.

OBJECTIVES: The purpose of our study was to describe the various magnetic resonance (MR) findings of pleomorphic adenoma and to interpret these findings. METHODS: MR studies of 33 pleomorphic adenomas and 13 malignant tumors in the major salivary glands were reviewed. RESULTS: High signal intensity on short-inversion-time inversion recovery (STIR) and T2-weighted (T2W) images, progressive enhancement on dynamic MR images, and high apparent diffusion coefficient (ADC) values on diffusion-weighted (DW) images reflected myxoid-dominant components in pleomorphic adenomas. Hypercellularity with less-myxoid stroma showed reduced signal intensity on STIR and T2W images and also reduced ADC values on DW images, and the peak of time versus signal intensity curves (TICs) was reached earlier on dynamic MR images. CONCLUSIONS: The MR images of hypercellularity components in pleomorphic adenoma overlap with those of malignant parotid tumors. Detecting myxoid components by STIR, T2W, DW, and dynamic MR images is useful for predicting whether salivary gland tumors are pleomorphic adenoma or not.

Adenoma, Pleomorphic↗
PubMedDate not supplied

Preoperative radiation therapy for carcinoma of the oropharynx: prognostic factors for locoregional control and survival.

BACKGROUND: To assess the role of preoperative irradiation and surgery in patients with oropharyneal cancer. MATERIALS AND METHODS: Seventy-five patients were treated with radiotherapy alone or followed by surgery. The stage distribution was stage II in 15 patients, stage III in 16 patients, stage IVA in 38 patients and stage IVB in 6 patients. RESULTS: Thirty-five patients were treated with radiotherapy alone and the remaining 40 underwent definitive surgery after radiation therapy. In the multivariate analysis, both good Karnofsky Performance Status (KPS) and complete response (CR) after radiation therapy had positive impact on locoregional control and survival. Overall survival at 5 years was 65% and 20% for KPS > or = 90% and KPS < 90%, respectively (p < 0.0001). Corresponding values for CR and non-CR were 80% and 35%, respectively (p = 0.0001). CONCLUSION: The results indicated that the KPS and complete response after radiation therapy were very sensitive surrogates for locoregional control and survival for cancer of the oropharynx.

Adult↗