PubMed Health⌕ Search

Biomedical subjects

Noboru Uchiyama

Publications and source records attributed to Noboru Uchiyama.

11 recordsLinked to original sources

Inhibition of tumor cell-induced platelet aggregation using a novel anti-podoplanin antibody reacting with its platelet-aggregation-stimulating domain.

The mucin-type sialoglycoprotein, podoplanin (aggrus), is a platelet-aggregating factor on cancer cells. We previously described up-regulated expression of podoplanin in malignant astrocytic tumors including glioblastoma. Its expression was associated with tumor malignancy. In the present study, we investigated podoplanin expression and platelet-aggregating activities of glioblastoma cell lines. First, we established a highly reactive anti-podoplanin antibody, NZ-1, which inhibits podoplanin-induced platelet aggregation completely. Of 15 glioblastoma cell lines, LN319 highly expressed podoplanin and induced platelet aggregation. Glycan profiling using a lectin microarray showed that podoplanin on LN319 possesses sialic acid, which is important in podoplanin-induced platelet aggregation. Interestingly, NZ-1 neutralized platelet aggregation by LN319. These results suggest that podoplanin is a main reason for platelet aggregation induced by LN319. We infer that NZ-1 is useful to determine whether platelet aggregation is podoplanin-specific or not. Furthermore, podoplanin might become a therapeutic target of glioblastoma for antibody-based therapy.

Animals↗

High-throughput analysis of lectin-oligosaccharide interactions by automated frontal affinity chromatography.

Frontal affinity chromatography (FAC) is a quantitative method that enables sensitive and reproducible measurements of interactions between lectins and oligosaccharides. The method is suitable even for the measurement of low-affinity interactions and is based on a simple procedure and a clear principle. To achieve high-throughput and efficient analysis, an automated FAC system was developed. The system designated FAC-1 consists of two isocratic pumps, an autosampler, and a couple of miniature columns (bed volume, 31.4 microl) connected in parallel to either a fluorescence or an ultraviolet detector. By use of this parallel-column system, the time required for each analysis was reduced substantially. Under the established conditions, fewer than 10 hrs are required for 100 interaction analyses, consuming as little as 1 pmol pyridylaminated oligosaccharide for each analysis. This strategy for FAC should contribute to the construction of a lectin-oligosaccharide interaction database essential for future glycomics. Overall features and practical protocols for interaction analyses using FAC-1 are described.

Animals↗

Development of a lectin microarray based on an evanescent-field fluorescence principle.

To investigate protein-carbohydrate interactions in a comprehensive and high-throughput manner, carbohydrate biosensors including microarrays have recently attracted increased attention. In this context, carbohydrate and lectin microarrays are emerging as techniques to meet such requisites. However, most of these methods adopt a conventional immuno-detection system, which requires repetitive washing steps before detection. Since lectin-carbohydrate interactions are relatively weak compared with those between antigens and antibodies, a more precise analytical method, which does not require any washing step, is desirable. We describe here a novel platform for lectin microarray that enables direct observation of lectin-carbohydrate interactions under equilibrium conditions, on the basis of an evanescent-field fluorescence-assisted detection principle. This method allows the analysis of a panel of glycoproteins (glycopeptides) in an extremely sensitive manner. The system also allows real-time observation of lectin-glycoprotein interactions in an aqueous phase. No washing procedures are required, thus relatively weak interactions are detectable. The described lectin microarray is expected to be useful for various fields of glycomics requiring high-throughput analysis of not only purified glycoproteins but also of crude samples.

Animals↗

Application of lectin microarray to crude samples: differential glycan profiling of lec mutants.

We recently developed a novel system for lectin microarray based on the evanescent-field fluorescence-detection principle, by which even weak lectin-oligosaccharide interactions are detectable without a washing procedure. For its practical application, cell glycan analysis was performed for Chinese hamster ovary (CHO) cells and their glycan profile was compared with those of their glycosylation-defective Lec mutants. Each of the cell surface extracts gave a significantly different profile from that of the parental CHO cells in a manner reflecting denoted biosynthetic features. Hence, the developed lectin microarray system is considered to be fully applicable for differential glycan profiling of crude samples.

Animals↗

Nocardia exalbida sp. nov., isolated from Japanese patients with nocardiosis.

Two bacterial strains isolated from different hospitals in Japan were subjected to a polyphasic analysis. Strains IFM 0803(T) and IFM 10383 were found to have morphological, biochemical, physiological and chemotaxonomic properties consistent with their classification in the genus Nocardia. Strains IFM 0803(T) and IFM 10383 clustered with the type strain of Nocardia xishanensis, showing 16S rRNA gene sequence similarities of 98.6-98.9 % with this species. The novel strains could be distinguished from N. xishanensis by a range of phenotypic properties. Based on their phenotypic and phylogenetic characteristics, the two isolates are proposed as members of a novel species of the genus Nocardia, Nocardia exalbida sp. nov., with the type strain IFM 0803(T) (=NBRC 100660(T) = JCM 12667(T) = DSM 44883(T)).

Humans↗

Mobility moment analysis of molecular interactions by capillary electrophoresis.

A new method for the quantitative evaluation of molecular interactions that are observed in electrophoresis is described. One component taking part in the interaction is labeled with a fluorescent dye and is subjected to capillary zone electrophoresis with fluorescence detection in the presence or absence of an unlabeled interacting component. Fluorescence signals are collected at constant time intervals, and the electropherograms are converted to represent the fluorescence signal against mobility. After baseline subtraction, the first statistical moment of fluorescence signals on the mobility axis is calculated. This moment represents the average mobility of a labeled component. The change in the mobility moment in the presence and absence of the unlabeled component is used to evaluate the degree of saturation of the binding site of a labeled molecule with an unlabeled molecule. Mixtures of fluorescence-labeled protein (Fab' fragment of antibody or concanavalin A) and its unlabeled interacting partner (alpha(1)-antitrypsin or succinylated ovalbumin, respectively) at various concentrations were injected into a bare-silica capillary, and zone electrophoresis was carried out. The change in the mobility moment of the fluorescence-labeled molecules was used to determine the dissociation constants of the complexes. The determined constants are comparable to those obtained by a well-established method, that is, an analysis based on the peak height of the complex. Since the mobility moment analysis is not affected by the total intensity of the signals, it should be advantageous in analyses in which multiple capillaries are used, in which the injection volume and the sensitivity of detection might be more difficult to control at constant values. The mobility moment analysis also has advantages for the analysis of heterogeneous samples, since the identification of peaks is not necessarily required.

Antigen-Antibody Reactions↗

Evanescent-field fluorescence-assisted lectin microarray: a new strategy for glycan profiling.

Glycans have important roles in living organisms with their structural diversity. Thus, glycomics, especially aspects involving the assignment of functional glycans in a high-throughput manner, has been an emerging field in the postproteomics era. To date, however, there has been no versatile method for glycan profiling. Here we describe a new microarray procedure based on an evanescent-field fluorescence-detection principle, which allows sensitive, real-time observation of multiple lectin-carbohydrate interactions under equilibrium conditions. The method allows quantitative detection of even weak lectin-carbohydrate interactions (dissociation constant, K(d) > 10(-6) M) as fluorescent signals for 39 immobilized lectins. We derived fully specific signal patterns for various Cy3-labeled glycoproteins, glycopeptides and tetramethylrhodamine (TMR)-labeled oligosaccharides. The obtained results were consistent with the previous reports of glycoprotein and lectin specificities. We investigated the latter aspects in detail by frontal affinity chromatography, another profiling method. Thus, the developed lectin microarray should contribute to creation of a new paradigm for glycomics.

Animals↗

[Advanced non-small cell lung cancer responded to both vinorelbine and carboplatin over long-term outpatient treatment].

We treated a patient with lung adenocarcinoma who responded to chemotherapy with vinorelbine (VNR) plus carboplatin (CBDCA) on an outpatient basis. The patient was a 68-year-old man. He visited a local physician complaining of wet coughing, headache and general fatigne. The symptoms remained unchanged and the patient was admitted to our department for treatment in June 2000. A massive shadow in the right upper lobe and multiple cerebral metastases were found. Based on this, the diagnosis was lung adenocarcinoma (T3N2M1, clinical stage IV). Whole-brain irradiation and systemic chemotherapy were initiated from July 2000. The patient received 1 course of systemic chemotherapy with vindesine (VDS) plus cisplatin (CDDP) on an inpatient basis. This regimen was replaced with combination therapy of paclitaxel (TXL) plus CBDCA in the outpatient setting, along with VNR plus CBDCA due to side effects caused by TXL. The cerebral metastases almost disappeared due to whole-brain irradiation. Chest CT after 3 courses revealed a reduction in primary tumor size. The VNR plus CBDCA combination therapy was continued for a further 6 courses. As the result, neither the primary tumor nor the cerebral metastases enlarged. The combination therapy with VNR plus CBDCA seems to be a useful regimen that can maintain high QOL and be conducted for a long term on an outpatient basis.

Aged↗

[A case of mediastinal metastasis of renal small cell carcinoma, performing CHOP therapy for an acute respiratory failure by the air way obstruction under the mechanical ventilation].

A case of mediastinal metastasis of renal small cell carcinoma was reported. A 45-year-old female was admitted to our hospital complaining of worsening dyspnea. The chest radiograph and CT showed stenosis of the bronchi bilaterally due to the mediastinal mass. Prior to pathological diagnosis, CHOP therapy with cyclophosphamide, adriamycin, vincristine and prednisolone was performed under mechanical ventilation for the purpose of resuscitation. The therapy was effective; and the was weaned from the mechanical ventilator, resulting in complete remission. Transbronchial samples from the left main bronchus confirmed that the mediastinal mass was identical pathologically to the renal small cell carcinoma (RSCC) resected 5 years before. As a result, the mediastinal mass was diagnosed as a metastatic focus of RSCC. RSCC is known to have one of the most unfavorable prognoses among malignancies. Despite efforts with chemotherapy, almost all cases that appear in the literature died within 1 year after diagnosis. No standard treatment modality has yet been established. Thus, the present case is rare because an RSCC relapse after a long free period went into remission as a result of CHOP therapy. It is suggested that CHOP therapy may well be an effective tool against RSCC, and could be a valuable choice for a treatment regimen.

Acute Disease↗

Determination of the affinity constants of recombinant human galectin-1 and -3 for simple saccharides by capillary affinophoresis.

The affinity constants of recombinant human galectin-1 and galectin-3 for sugars were determined by capillary affinophoresis. The monoliganded affinophore contains p-aminophenyl-beta-lactoside as an affinity ligand in the matrix of succinylglutathione and has three negative charges. An analysis of the mobility change of the lectins caused by the affinophore and its inhibition by neutral sugars allowed, for the first time, a determination of the affinity constants between the binding sites of the lectins and sugars. The relative magnitude of the affinity constants for each of the sugars in terms of dissociation constants found to be consistent with previously reported data on the concentrations of sugars that caused a 50% inhibition (I50) in the binding assay of the lectin to oligosaccharide-immobilized agarose beads but the absolute values of the dissociation constants were considerably smaller than the I50 values. Capillary affinophoresis indicated microheterogeneity of the lectin preparations and enabled the separate analysis of the affinity of each component simultaneously showing the advantage in using a separation method for analysis of bioaffinity.

Antigens, Differentiation↗

[Usefulness of clinical pathway for community-acquired pneumonia as both an educational and a cost-management tool--an intervention study to compare the usefulness of management with a critical pathway to historical control of conventional management].

To delineate the usefulness of a clinical pathway for community-acquired pneumonia (CAP) as an educational tool as well as a cost management tool, we conducted a prospective controlled trial including a historical control group. Consecutive CAP patients classified under Category 3 of the American Thoracic Society and admitted to our hospital were evaluated. Using the clinical pathway method, 42 patients were managed between April and December 2000 as the intervention group, and 33 patients received conventional management between April and December 1999 as a historical control. For the intervention group, the clinical pathway, which was a time-task matrix formatted with consideration for guidance for disease treatment, laboratory tests, physical examinations, oxygen saturation monitoring, ambulation, diet, education for the patient and clinical outcomes, was implemented. We determined (1) educational effect, measured using reduction of delay caused by physicians; (2) quality of clinical practice, measured using the success rate of the initial antimicrobial therapy and readmission rate; and (3) economic efficacy, measured using health care cost and length of hospital stay. The delay caused by physicians was reduced by 16% in the Intervention Group (5% vs. 21%; p = 0.045). The success rates of initial antimicrobial therapy in the two groups were similar (85.7% vs. 84.8%). In the intention-to-treat set, the median value of health care cost was reduced by yen 48,055 (yen 277,460 vs. yen 325,515; p = 0.017) and the median length of a hospital stay was shortened by 3 days (8 vs. 11 days; p = 0.0007) in the Intervention Group. In conclusion, the clinical pathway had an educational effect on physicians regarding the management of hospitalized patients with community-acquired pneumonia as well as on the cost management.

Aged↗