Search PubMed⌕ Search

Biomedical subjects

N Kataoka

Publications and source records attributed to N Kataoka.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Measures against hospital infection for students in medical schools in Japan--a survey by questionnaires].

We sent questionnaires to 80 medical schools in Japan to know what the problems in hospital infection for students in medical schools are. Seventy-one % were sent back to us. There have been hospital infection from patients to students in 12% of the medical schools, included 3 cases each of measles, chickenpox and mumps, 2 cases each of rubella, hepatitis B and tuberculosis. Fourteen % of the medical schools had reports about the past history of infection and vaccination from students, 70% of the schools determined their antibodies and the 28% did nothing. Ninety-three%, 25%, 23%, 18%, and 15%, of the schools determined antibodies for hepatitis B, rubella, measles, chickenpox and mumps, respectively. Some assays of the measurement were low in sensitivity. The cost for the determination was fully paid in 48% of the schools, but only partially supported in 35%. Tuberculin reaction was performed in 40% of the schools and then BCG was done in 57%. Vaccination was recommended in 40% of the schools. The cost of vaccination was all paid in 38% of them, which was only for hepatitis B, and partially supported in 15% of them.

Cross Infection↗
PubMed2000

[Comparison of positivity rates for antibodies against measles, rubella, chickenpox and mumps by assays].

Our previous study found mistakes by some doctors in the choice of an assay for determining antibodies in Japan. To compare the positivity rates for antibodies by assays, we measured the antibodies of measles, rubella, chickenpox and mumps from the same sera using such methods as the EIA, HI and CF assays. The subjects were 175 nursing students. The positivity rates for measles, chickenpox and mumps by the EIA assay were 96.6%, 93.7%, and 83.3%, respectively. Those for rubella by the HI and CF assays were 92.0% and 10.1%. The sensitivity rates for measles, chickenpox and mumps by the HI and CF assays, based on the results of the EIA assay, were 75.1%, 102.4% and 69.2% in the HI assay, and 20.6%, 38.7% and 8.0% in the CF assay, respectively. Our previous study showed that the sensitivity of the HI assay for rubella antibody is same as that of the EIA assay in Japan. Currently an EIA assay should be chosen for these antibodies and the HI assay or IAHA assay should be possible selections for rubella and chickenpox. However, international comparison of the cutoff titers for these antibodies should be considered.

Antibodies, Viral↗
PubMed2000

Low induction of varicella-zoster virus-specific secretory IgA antibody after vaccination.

Breakthrough after varicella vaccination occurs in approximately 2. 6% approximately 18.6% of immunocompetent children, but the reason has not been demonstrated clearly. As a first defense, specific secretory IgA antibody on the mucosa plays an important role in preventing invasion of microorganisms. To examine induction of varicella-zoster virus (VZV) specific secretory IgA after natural infection and vaccination and its booster mechanisms, 143 salivary samples were tested by ELISA. The VZV-secretory IgA values were significantly higher in the matched children after natural chickenpox than in those after vaccination, although the total secretory IgA did not differ between them. Two (7%) of the vaccinees lacked the sIgA antibody. In the elderly and in immunocompromised children, the VZV-secretory IgA values were no lower than those in healthy children, and they did not lack VZV-secretory IgA. The doctors and nurses taking care of patients with chickenpox had higher values than the other groups as did individuals who had had herpes zoster recently. VZV-secretory IgA was thought to be stimulated by exogenous and reactivated endogenous VZV to neutralize VZV with weak activity. These results suggest that low or no induction of VZV-secretory IgA antibody after vaccination may be one of the possible explanations for a breakthrough.

Aged↗
PubMed2000

[Genetic analysis of two patients with adenosine deaminase (ADA)-deficiency: detection of three novel mutations and characterization of two paradoxical carriers].

Genetic basis of two patients (AT, MT) with ADA deficiency was studied. We identified three novel mutations (119 Q-->Stop, 235 R-->Q, one base deletion in Exon 4) from the patients. 119 Q-->Stop was detected in AT and her father. Deletion of one base in Exon 4 which would change the reading frame after codon 105 H, was detected in MT, her father and brother. There was no relation between the two families, however, 235 R-->Q was also detected in both the patients and their mothers. Extremely low ADA activity of PBMCs was revealed in healthy MT's mother and brother just as MT, although their dAXP levels of RBCs showed significantly lower than that of MT. We defined that they shared an additional mutation (310 M-->T) together with the mutation described above, respectively. EBV-transformed B-cell line (EBV-B) were established from the carriers. To our surprise, ADA activity of their lines was 1/10-1/5 of normal. The result of heat treatment studies using the EBV-B showed that the mutant ADA rapidly lose its enzyme activity without degradation of the protein. It suggests that 310 M-->T mutant ADA rapidly lost its enzyme activity due to conformational change of the catalytic site of ADA.

Adenosine Deaminase↗
PubMed1999

Transportin-SR, a nuclear import receptor for SR proteins.

The SR proteins, a group of abundant arginine/serine (RS)-rich proteins, are essential pre-mRNA splicing factors that are localized in the nucleus. The RS domain of these proteins serves as a nuclear localization signal. We found that RS domain-bearing proteins do not utilize any of the known nuclear import receptors and identified a novel nuclear import receptor specific for SR proteins. The SR protein import receptor, termed transportin-SR (TRN-SR), binds specifically and directly to the RS domains of ASF/SF2 and SC35 as well as several other SR proteins. The nuclear transport regulator RanGTP abolishes this interaction. Recombinant TRN-SR mediates nuclear import of RS domain- bearing proteins in vitro. TRN-SR has amino acid sequence similarity to several members of the importin beta/transportin family. These findings strongly suggest that TRN-SR is a nuclear import receptor for the SR protein family.

Amino Acid Sequence↗
PubMed1999

The relation between the number of PBSC and number of leukaphereses in children.

Although PBSC transplantation has an advantage over BM transplantation in that fewer burdens are placed on the patient at the time of stem cell collection, the number of collected cells decreases when leukapheresis is done repeatedly. We examined the relation between the number of times leukapheresis is performed and the number of mononuclear cells (MNC), CD34+ cells, and colony-forming unit-granulocyte-macrophages (CFU-GM) collected. The percentage of CD34+ cells was measured by flow cytometry and the number of CFU-GM was measured by a progenitor assay. The number of cells collected was significantly decreased by the third collection. Therefore, to secure enough cells for transplantation, leukapheresis ideally should be performed no more than twice if PBSC collection is to be efficient.

Adolescent↗
PubMed1999

Co-expression of integrin-associated protein (IAP/CD47) and its ligand thrombospondin-1 on human granulosa and large luteal cells.

In the present study, we have raised a monoclonal antibody (mAb) designated OG-4 against human granulosa cells (GC). By immunohistochemistry, the expression of OG-4 antigen was observed on human GC and large luteal cells, but not on thecal and small luteal cells. A complementary DNA (cDNA) clone encoding OG-4 antigen was screened and isolated by a panning method using OG-4 mAb from a human corpus luteum (CL) cDNA library that was expressed transiently in COS-7 cells. Nucleotide sequencing revealed that OG-4 antigen was identical to integrin-associated protein (IAP)/CD47 antigen. Subsequent reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that the isoform 2 mRNA of IAP is predominantly expressed in human GC and CL. The expression of thrombospondin-1 (TSP-1), which is a ligand for IAP, was also observed in human GC by immunocytochemistry and RT-PCR. Co-expression of IAP and TSP-1 on human GC may suggest that TSP-1 has a physiological role in GC function possibly via IAP in an autocrine fashion.

Adult↗
PubMed1999

CD9 is expressed in extravillous trophoblasts in association with integrin alpha3 and integrin alpha5.

The CD9 molecule is a 24-27 kDa cell surface glycoprotein, which may be related to Schwann cell migration and adhesion. In this study, we examined the expression of CD9 in human extravillous trophoblasts, which invade into the endometrium during implantation and placentation. CD9 was detected immunohistochemically on the extravillous trophoblasts in the cell columns of first trimester placentae, but not on villous trophoblasts. In the second and third trimester, CD9 was highly expressed on the extravillous trophoblasts in the basal plate of placentae, and in the chorion laeve in the fetal membrane of term placentae. The molecular mass of CD9 in the chorion laeve was shown to be 27 kDa by Western blotting. The mRNA of CD9 was also detected in the chorion laeve by reverse transcription-polymerase chain reaction (RT-PCR). Proteins were purified from chorion laeve by affinity chromatography with anti-integrin alpha3 and alpha5 monoclonal antibodies and Western blotting, revealed that CD9 was associated with both integrins. These findings indicate that CD9 is a differentiation-related molecule present in the extravillous trophoblasts. Since it is associated with integrin alpha5 which has been proposed to regulate trophoblast invasion, CD9 may be implicated in trophoblast invasion at the feto-maternal interface.

Antigens, CD↗
PubMed1999

CD9 is involved in invasion of human trophoblast-like choriocarcinoma cell line, BeWo cells.

The CD9 molecule is expressed on human extravillous trophoblasts, which invade the endometrium during implantation and placentation. To elucidate the role of CD9 in trophoblastic function, we investigated the expression of CD9 protein and mRNA in BeWo cells, a human trophoblast-like choriocarcinoma cell line, using immunohistochemistry, Western blotting and reverse transcription-polymerase chain reaction (RT-PCR). When BeWo cells were cultured with anti-CD9 monoclonal antibodies (mAb), their invasion through the extracellular matrices was significantly enhanced in a dose-dependent manner. Cell proliferation and human chorionic gonadotrophin production were unaffected. On the other hand, culture in the presence of mAb against integrins alpha3, alpha5 and beta1, which partially block the interaction with the extracellular matrices, inhibited BeWo cell invasion. Anti-CD9 monoclonal antibody had a stimulatory effect on BeWo cell invasion in the presence of anti-integrin alpha3 antibody. In contrast, it had no effect in the presence of mAb against integrins alpha5 and beta1, which were also highly expressed on BeWo cells. These findings suggest that CD9 has a function connected with the invasive properties of BeWo cells, which is partially mediated by integrin alpha5beta1. This may relate to the involvement of CD9 in trophoblastic invasion.

Antibodies, Monoclonal↗
PubMed1999

Clinical results of transcatheter arterial infusion for uterine cervical cancer.

The effects of transcatheter intraarterial infusion of anticancer drugs on the prognosis of cervical cancer were retrospectively studied. Two or three sessions of transcatheter arterial infusion therapy were performed for 68 patients with primary uterine cervical cancer. The number of patients with stage I, II, III, or IV disease were 13, 22, 24, and 9, respectively. Patients with squamous cell carcinoma comprised 3, 17, 17, and 5 of the respective groups, and the patients with stage I and II disease had either adenocarcinoma or adenosquamous carcinoma, or bulky tumor (>4 cm). The drugs infused were cisplatin (60-70 mg/m2), doxorubicin hydrochloride (30-40 mg/m2), mitomycin (15 mg/m2), and 5-fluorouracil (500 mg/body). They were infused via the bilateral internal iliac arteries. Fifty-eight of the 68 patients (85%) received a radical hysterectomy after transcatheter arterial infusion: 12 of 13 with stage I disease, 21 of 22 with stage II disease, 20 of 24 with stage III disease, and five of nine with stage IV disease. Two patients with stage III disease received radical radiotherapy. The other eight patients (one with stage I disease, one with stage II disease, two with stage III disease, and four with stage IV disease) did not receive an operation after transcatheter arterial infusion because they had distant metastases at the time of operation. Thirty-two of 58 patients (56%) received postoperative radiotherapy. The complete histologic response rates (no active cancer cells) after transcatheter arterial infusion were: 2 of 12 patients with stage I disease, 3 of 21 patients with stage II disease, 5 of 20 patients with stage III disease, and one of five patients with stage IV disease. Tumors with squamous cell carcinoma disappeared at a significantly better rate (10/36, 28%) than did tumors with adenocarcinoma or adenosquamous cell carcinoma (1/22, 5%; p < 0.05). The overall 5-year survival rates of the patients with stages I, II, and III disease were 92.3%, 62.2%, and 71%, respectively. The 5-year survival rates of the patients who underwent surgery with stage I, II, and III disease were 100%, 66.3%, and 71.5%, respectively. Leukocytopenia and thrombocytopenia occurred as an acute complication in 75% and 79% of the patients, respectively. As a late complication, ileus occurred in 7%. Transcatheter arterial infusion may improve the prognosis of patients with cervical cancer without increasing the incidence of late complications.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[Accumulative vaccination rate of rubella and positive antibody rate in an area of Japan--future problems with rubella].

The rubella vaccination rate remarkably decreased in Japan after a revised vaccination law was passed in 1994, as a result of which individual vaccination replaced mass vaccination at each school. We investigated the rubella antibody of 887 students and the accumulative rubella vaccination rate in an area of Okayama. The vaccination rate in Ibara, where children were inoculated individually, was 22.8%. In contrast, in Yoshii, where the vaccination was done as mass at each school, the rate was 89.8%. After 2003, when the transit period of the law ends, children 12-90 months of age will be the subjects for rubella vaccine. We presume that the vaccination rate in the future will reach 40-50% through accumulative vaccination. Such a rate of vaccination cannot prevent rubella epidemics and congenital rubella syndrome. In addition, an individual's rubella vaccination is generally done once during lifetime. We doubt whether the immune response induced by a vaccine can be maintained for more than 20 years without boosting. We think that a second vaccination is necessary for at least young girls, and this should be performed as mass at each school.

Adolescent↗
PubMed1999

[A case of Chlamydia trachomatis and Mycoplasma pneumoniae coinfection in a child].

Mycoplasma pneumoniae infection is often experienced as community-acquired pneumonia, whereas Chlamydia trachomatis pneumonia is sometimes experienced as a vertical infection from mother to child through delivery, but is rare after six months of age. We reported the first case to date of a seven-year-old boy with coinfection of C. trachomatis and M. pneumoniae. The patient, who was referred to our hospital because of suspected pneumonia, had had severe cough and pyrexia for four days before his admission. The coinfection was confirmed because the antibodies to both bacteria were significantly increased. In addition the PCR for C. trachomatis detected the presence of C. trachomatis in the throat even after treatment. The PCR from a cervix swab of his mother and from a throat swab of his father were negative, but their antibodies to C. trachomatis were positive. We think that this may have been community-acquired pneumonia or due to persistent infection after a vertical transmission.

Child↗
PubMed1998

A novel function for SMN, the spinal muscular atrophy disease gene product, in pre-mRNA splicing.

Spinal muscular atrophy (SMA) is a common motor neuron degenerative disease that results from reduced levels of, or mutations in, the Survival of Motor Neurons (SMN) protein. SMN is found in the cytoplasm and the nucleus where it is concentrated in gems. SMN interacts with spliceosomal snRNP proteins and is critical for snRNP assembly in the cytoplasm. We show that a dominant-negative mutant SMN (SMNdeltaN27) causes a dramatic reorganization of snRNPs in the nucleus. Furthermore, SMNdeltaN27 inhibits pre-mRNA splicing in vitro, while wild-type SMN stimulates splicing. SMN mutants found in SMA patients cannot stimulate splicing. These findings demonstrate that SMN plays a crucial role in the generation of the pre-mRNA splicing machinery and thus in mRNA biogenesis, and they link the function of SMN in this pathway to SMA.

Autoantigens↗
PubMed1998

Tumor response to neoadjuvant chemotherapy correlates with the expression of P-glycoprotein and PCNA but not GST-pi in the tumor cells of cervical carcinoma.

OBJECTIVE: To identify the clinicopathological and chemoresistant factors predicting the response to neoadjuvant chemotherapy and the patient prognosis in high-risk cervical carcinomas. METHODS: We retrospectively reviewed 47 patients with locally advanced or bulky cervical carcinoma treated with two courses of intraarterial infusion of cisplatin, doxorubicin, mitomycin C, and 5-fluorouracil (5-FU), followed by radical hysterectomy at our hospital between 1988 and 1995. Expressions of the chemoresistance-related proteins, such as P-glycoprotein, glutathione S-transferase pi (GST-pi), and proliferating cell nuclear antigen (PCNA) in the tumor cells, were examined by immunohistochemistry using pretreatment biopsy specimens. These results were compared with the chemotherapeutic response, which was evaluated by magnetic resonance imaging (MRI) and histopathology. Outcome of the patients was also studied. RESULTS: Chemotherapeutic effect of either complete (CR) or partial (PR) response on MRI was obtained in 36 of the 47 (86%) patients. Poor response to chemotherapy was significantly correlated with P-glycoprotein expression (P < 0.005) and low PCNA labeling (P < 0. 05), but not GST-pi expression in the tumor cells. Independent prognostic factors for patient survival were parametrial involvement and lymph node metastasis. Neither the expression of GST-pi nor PCNA was correlated with the patient survival. CONCLUSION: Assessment of the expression of P-glycoprotein and PCNA is potentially useful for the prediction of tumor response to neoadjuvant chemotherapy for cervical carcinomas.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1998

Effect of flow direction on the morphological responses of cultured bovine aortic endothelial cells.

The effect of flow direction on the morphology of cultured bovine aortic endothelial cells is studied. Fully confluent endothelial cells cultured on glass were subjected to a fluid-imposed shear stress of 2 Pa for 20 min and 24 h using a parallel plate flow chamber. Experiments on shear flow exposure were performed for (i) one-way flow, (ii) reciprocating flow with a 30 min interval and (iii) alternating orthogonal flows with a 30 min interval. After flow exposure, the endothelial cells were fixed and F-actin filaments were stained with rhodamine phalloidin. Endothelial cells were observed and photographed by means of a microscope equipped with epifluorescence optics. The shape index (SI) and angle of cell orientation were measured, and F-actin distributions in the cells were statistically studied. Endothelial cells under the one-way flow condition showed marked elongation (SI = 0.39 +/- 0.16, mean +/- S.D.) and aligned with the flow direction. In the case of the reciprocating (SI = 0.63 +/- 0.14) and the alternating orthogonal flows (0.64 +/- 0.14), cells did not elongate so strongly as in the case of one-way flow. Although most cells in the reciprocating flow aligned with the flow direction, the cell axes in the alternate orthogonal flow distributed around a mean value of -45.1 degrees with a large S.D. value. Endothelial cells can be expected to recognise the flow direction, and change their shape and F-actin structure.

Actins↗
PubMed1998

Isolation and characterization of an active mannanase-producing anaerobic bacterium, Clostridium tertium KT-5A, from lotus soil.

Of 10 strains of mannanase-producing anaerobic bacteria isolated from soils and methanogenic sludges, Clostridium tertium KT-5A, which was isolated from lotus soil, produced high amounts of extracellular beta-1,4-mannanase. The isolate was an aerotolerant anaerobe without quinon systems; the cell growth cultivated with no addition of reducing agents was also stable. High yields of mannanase were obtained by inducing enzyme production with galactomannan guar gum and beef extract/peptone as carbon and nitrogen sources, respectively. Fermentation end products on galactomannan fermentation were formate, acetate, lactate, butyrate, carbon dioxide and hydrogen. The extracellular mannanase displayed high activity on galactomannans of locust bean gum galactose/mannose (G/M) ratio 1:4 and spino gum (G/M 1:3), but weak activity on guar gum galactomannan (G/M 1:2) and konjac glucomannan. As far as is known, this is the first report on the isolation of an active mannanase-producing anaerobic bacterium from natural environments.

Bacillus subtilis↗
PubMed1998

Molecular genetic and immunohistochemical study of autosomal recessive Alport's syndrome.

A DNA analysis of autosomal type IV collagen alpha3 and alpha4 chain genes (COL4A3 and COL4A4) and an immunohistochemical study of type IV collagen alpha1 to alpha6 chains were performed in an inbred family with autosomal recessive Alport's syndrome (AS). A linkage study using polymorphic markers around the COL4A3/COL4A4 genes clearly differentiated the affected patients from healthy individuals. These patients were homozygous for all markers analyzed, whereas their parents were heterozygotes. Because of the large size of both the genes and the heterogeneous range of the mutations of these genes, linkage analysis by using highly polymorphic markers is still the method of choice in genetic counseling for autosomal recessive AS, as well as for the X-linked form. Although the distribution of alpha1 and alpha2 chains in the index patient and her affected sister were normal, the alpha3 and alpha4 chains were completely defective in the renal basement membrane (BM). The alpha5 chain could be found in Bowman's capsular basement membrane (BCBM) but not in the glomerular basement membrane (GBM). In addition, our study showed, for the first time, that the alpha6 chain in BCBM is spared in this form of AS. This abnormal pattern of type IV collagen could be a useful tool for differentiation of the autosomal recessive type from the X-linked type of AS.

Adolescent↗