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N Suzuki

Publications and source records attributed to N Suzuki.

At least 361 records · Page 20Linked to original sources
PubMed1999

Expression of Babesia equi merozoite antigen-2 by recombinant baculovirus and its use in the ELISA.

In this study, the gene encoding Babesia equi merozoite antigen-2 was inserted into a baculovirus transfer vector, and a recombinant virus expressing B. equi merozoite antigen-2 was isolated. Two B. equi merozoite antigen-2-related recombinant baculovirus-expressed peptides of 25 and 30 kDa were detected with a murine anti serum against B. equi merozoite antigen-2; these corresponded to the native B. equi merozoite antigen-2 and were secreted into the supernatants of insect cell cultures. Recombinant B. equi merozoite antigen-2 was not effected by tunicamycin treatment, indicating that B. equi merozoite antigen-2 was not glycosylated. The potential of recombinant B. equi merozoite antigen-2 for use in the ELISA was evaluated by measuring the antibody response to B. equi merozoite antigen-2 in horses experimentally infected with B. equi.

Amino Acid Sequence↗
PubMed1999

Increase in nucleoli after x-radiation of fibroblasts of patients with Gorlin syndrome.

Gorlin syndrome (GS) is an autosomal dominant disorder in which patients are abnormally susceptible to ionizing radiation with radiotherapeutic doses. Radiogenic basal cell carcinomas may develop with a short latent period in patients. The mechanisms underlying the abnormal radiosusceptibility of cells in patients with GS has not been well characterized. In this study we report an increase in the number of nucleoli in fibroblast cells from 3 patients with GS after x-radiation. In GS fibroblasts, the increase in nucleolus number concomitant with the increase of ribonucleoprotein immunoreactive aggregates within the nucleus was observed after x-radiation, whereas significant change was not found in normal fibroblasts derived from healthy donors. This increase disappeared when cells were cultured with the RNA synthesis inhibitor actinomycin D after x-radiation but not when they were cultured with cycloheximide or aphydicolin, which are protein and DNA synthesis inhibitors, respectively. Ultraviolet exposure did not induce remarkable changes in the GS nucleoli. Thus the increase in nucleoli was induced after x-radiation of GS fibroblasts, and this increase seemed to be related to RNA synthesis metabolism.

Basal Cell Nevus Syndrome↗
PubMed1999

Incidence of intrahepatic biliary cysts in biliary atresia after hepatic portoenterostomy and associated histopathologic findings in the liver and porta hepatis at diagnosis.

BACKGROUND/PURPOSE: The association of intrahepatic biliary cysts in biliary atresia (BA) after hepatic portoenterostomy has drawn the attention of many pediatric surgeons and has become an important subject in clinical management, but the incidence and causes of this association are not well known. METHODS: During the last 14 years, we operated on 33 BA patients by hepatic portoenterostomy. Five patients could not be followed up over a 1-year period, so the remaining 28 patients had their intrahepatic structure investigated by periodic magnetic resonance imaging (MRI), and were confirmed at autopsy. The authors also reviewed the preoperative conditions of these patients and the histopathologic changes in the liver biopsy and the porta hepatis specimens taken at portoenterostomy. RESULTS: (1) Intrahepatic biliary cysts were found in 6 of the 28 patients studied (21%). Of 16 patients who were operated on after 1989 and are undergoing follow-up by MRI, 4 (25%) had cysts. (2) Five of the 6 patients with cysts had episodes of cholangitis before or at the time of discovery of the cysts, and 4 of them have had their jaundice reappear since the discovery of the cysts. (3) The intralobular spaces (ILS) with fibrosis and the number of bile ducts had increased in the group with cysts compared with those in the group without cysts. (4) The bile duct maximum size in the porta hepatis (PH) was similar in the groups with and without cysts, but a denudation of the mucosal lining cells in the duct, and a fibrosis and inflammation around the duct had increased in the group with cysts compared with those in the group without cysts. (5) Statistically, the fibrosis found in the ILS and the inflammation around the bile duct found in the PH were induced as a correlative factor affecting cyst formation. CONCLUSIONS: The association of intrahepatic biliary cysts in BA after portoenterostomy is frequent. The fibrous change in the ILS and the inflammatory process around the bile ducts might be potential causes of cyst formation.

Bile Ducts↗
PubMed1999

A case of well-differentiated, fetal-type hepatoblastoma with very low serum alpha-fetoprotein.

Serum alpha-fetoprotein (AFP) is elevated in 96.6% of infants and children with hepatoblastoma and hepatocarcinoma. Serum AFP was of normal level in only one case of immature-type hepatoblastoma, and very low in only one case of fetal-type hepatoblastoma among 43 cases reviewed in 1986. Recently, a case of hepatoblastoma with very low serum AFP was encountered in the authors' surgical department. In October 1998, a 55-month-old girl was admitted. Her birth weight was 717 g. A large space-occupying lesion (SOL) located in the left lobe of the liver was seen by magnetic resonance imaging (MRI), and her serum AFP level was 322 ng/mL with a subfractionation pattern of the "benign liver disease" type based on reactivity with lens culnaris hemagglutinin and concanavalin A. The patient underwent successful left lobectomy, and histological examination showed that the tumor, weighing 268 g, was hepatoblastoma of the well-differentiated, fetal type. Immunohistochemistry findings for AFP were negative. A hepatic mass in infants and children with low serum AFP level indicates the presence of either well-differentiated or immature hepatoblastoma, or fibrolamellar hepatocellular carcinoma. Subfractionation of AFP may contribute to the differential diagnosis of these subtypes.

Child, Preschool↗
PubMed1999

The effects of alterations in nitric oxide levels in the paraventricular nucleus on copulatory behavior and reflexive erections in male rats.

PURPOSE: To examine the effects of altered nitric oxide (NO) levels in the paraventricular nucleus (PVN) on copulatory behavior and reflexive erections in male rats. MATERIALS AND METHODS: Extracellular nitrite (NO2-) and nitrate (NO3-) levels were measured in the PVN following administration of the NO precursor L-arginine (L-arg, 10 mM), the NO synthase inhibitor N(G)-monomethyl L-arginine (L-NMMA, 10 mM), or Ringer's solution via a dialysis probe to the PVN. The effects of alterations in extracellular NO on reflexive erections and copulatory behavior were assessed. RESULTS: L-arg administration was associated with significant elevations of extracellular NO2- and NO3- in the PVN, while L-NMMA significantly reduced NO2- and NO3- levels. A corresponding increase in reflexive erections was noted during infusion of L-arg in the PVN, with a corresponding decrease in reflexive erections observed during administration of L-NMMA into the PVN (Student's t test for paired samples, p <0.05). Mount rate was unaffected by infusion of the either L-arg or L-NMMA. CONCLUSIONS: Altered NO levels in the PVN affected the frequency of reflexive erections, but not the mount rate. These studies contrast with previous observations of the effects of altered NO levels in the MPOA, and support the hypothesis that physiological specificity in the actions of NO on discrete brain nuclei may have important implications to erectile physiology and dysfunction.

Animals↗
PubMed1999

Autoimmune disease induced by dendritic cell immunization against leukemia.

Induction of an optimal immune response will likely be a prerequisite for successful immunotherapy of human leukemias and other malignancies. Dendritic cells are highly effective at inducing an immune response to antigens to which the host is unresponsive, while transgenic expression of the costimulator molecule CD40 ligand (gp39/CD154) and the T cell growth factor interleukin 2 (IL2) are also able to augment immune responsiveness. We therefore investigated whether a combination of these two distinctive approaches to immunostimulation could safely increase the anti-tumor immune response compared to each stimulus alone. We injected BALB/CBYJ mice with syngeneic dendritic cells (DC) exposed to A20 lymphoblastic leukemia cell-derived peptides and proteins which had been acid-eluted from the cell surface. In additional mice, the pulsed DC were mixed with genetically modified syngeneic fibroblasts that were expressing CD40 ligand or secreting interleukin 2 (IL2). Three days after their third, weekly, vaccination, they were challenged with parental A20 cells. Tumor growth was suppressed by responses to pulsed DC alone (P < 0.02). This suppression was further enhanced when pulsed DC were coinjected with fibroblasts expressing CD40 ligand and IL2 (P < 0.0005 compared to DC alone) even though CD40 ligand and IL2-expressing fibroblasts alone offered no significant protection in this model. Mice receiving the full complement of immunostimulants either failed to develop visible tumors or developed small tumors which quickly necrosed and regressed, allowing the mice to become long term tumor-free survivors. Antibody mediated depletion of either CD4+ or CD8+ T-cell subset significantly reduced the level of protection afforded by the vaccination. However, it became evident that this intensive stimulation of the immune system lead not only to tumor eradication but also to destruction of cells bearing normal self antigens. Hence, 60 days after challenge with A20 cells all mice in the DC/IL2/CD40 ligand group developed a severe, systemic autoimmune disorder that resembled graft versus host disease and manifest itself by significant peripheral blood cytotoxicity against autologous fibroblasts, blood dyscrasias, gross hepatosplenomegaly, cachexia and fur loss. This phenomenon depended on CD8+ cytotoxic T lymphocytes. Our results therefore suggest that the most effective strategies of immunotherapy against leukemia may also exceed the threshold of anergic cells, leading to a loss of self tolerance to normal self-antigens and the induction of an CD8+ anti-self effector response.

Animals↗
PubMed1999

Determination of MKT-077, a novel antineoplastic agent, in plasma samples by high-performance liquid chromatography and its application to pharmacokinetics in rats.

A simple high-performance liquid chromatographic method was developed for determination of a novel antineoplastic agent MKT-077 in plasma. MKT-077 was extracted from 50 microl of plasma with acetonitrile containing 1 ml trifluoroacetic acid per liter. Chromatographic separation was achieved within 13.5 min using a reverse-phase Puresil C18 analytical column. A visible detector operated at 490 nm was used. The linearity of the calibration curve was obtained (r2 = 0.99986) over the analytical range of 10-500 ng/ml(-1). The intra- and inter-assay precision was in the range of 0.9-11.1 and 0.3-4.4%, respectively. The intra- and inter-assay bias ranged from -7.3 to 11.1% and from 0.4 to 11.6%, respectively. The utility of this assay was demonstrated after the administration of a single dose of MKT-077 to rats. The plasma elimination half-life of MKT-077 was 1.8-4 h.

Animals↗
PubMed1999

Effect of intravenous omega-6 and omega-3 fat emulsions on nitrogen retention and protein kinetics in burned rats.

The effect of omega-3 fat emulsion on nitrogen retention and kinetics in relation to fatty acid profile were investigated in burned rats receiving total parenteral nutrition (TPN). A fat emulsion of a structured symmetrical triacylglycerol containing only eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (2:1) was prepared. Sprague-Dawley rats were fed by fat-free chow for 2 wk. Then rats were fed exclusively with one of three types of TPN for 7 d. Animals in group C received fat-free TPN (n = 11). Group omega 6 received safflower oil fat emulsion, which accounted for 20% of total caloric intake (n = 11). Group omega 3 received fat emulsion containing only EPA and DHA (1% of total calories, n = 11), in addition to safflower oil emulsion (19% of total calories). On day 5, each rat was subjected to 20% full-thickness scald burns. Rats were sacrificed under ether anesthesia 48 h after burning. The rats in group C became deficient in omega-6 essential fatty acids. Cumulative nitrogen balance was decreased significantly in group omega 6. The rates of whole-body protein synthesis were increased significantly in both groups omega 6 and omega 3. In omega 6, however, the rates of whole-body protein breakdown were increased significantly. In conclusion, the rates of whole-body protein breakdown increased and nitrogen retention was aggravated significantly in animals administered the safflower oil emulsion. Significant increases of urinary excretion of total catecholamine were also observed. Prostaglandin E2 and thromboxane B2 concentrations were not significantly different among three groups. Supplementation with the new omega-3 fat emulsion, however, improved protein metabolism in burned rats receiving TPN.

Animals↗
PubMed1999

The concept of the digital morgue as a 3D database.

The concept of the construction of a 3-dimensional database of a body structure, or a digital morgue, and its advantages to the field of forensic medicine was proposed. The digital morgue stores the body structure of each case as a 3D data set of sectioning planes of the whole body obtained from computer tomograms or magnetic resonance imaging figures. Furthermore, the medical virtual reality technique makes it possible to perform a simulated autopsy of the body in the digital morgue (virtual autopsy). Therefore, in the digital morgue, retrospective observation and quantitative analysis of the structural damage of the body are possible using high-dimensional medical imaging and medical virtual reality.

Journal Article↗
PubMed1999

Tamoxifen-DNA adducts detected in the endometrium of women treated with tamoxifen.

Women treated for breast cancer with tamoxifen are at increased risk of developing endometrial cancer. This carcinogenic effect has been attributed to estrogenic stimulation and/or to a genotoxic effect of this drug. To examine genotoxicity, we developed a (32)P-postlabeling TLCL/HPLC procedure for quantitative analysis of tamoxifen-DNA adducts in endometrial tissue. This assay is several orders of magnitude more sensitive than those previously used for this purpose; with it, we can detect five tamoxifen-DNA adducts in 10(11) bases. Endometrial tissue was obtained from women undergoing tamoxifen therapy and from untreated control subjects. DNA adducts, identified as trans and cis epimers of alpha-(N(2)-deoxyguanosinyl)tamoxifen, were detected in six of thirteen patients in the tamoxifen-treated group. Levels of trans and cis adducts ranged from 0.5 to 8.3 and from 0.4 to 4.8 adducts/10(8) nucleotides, respectively. Tamoxifen-DNA adducts were not detected in endometrial tissue obtained from the control subjects. We conclude from this study that one or more tamoxifen metabolites react with endometrial DNA to form covalent adducts, establishing the potential genotoxicity of this drug for women and suggesting the use of TAM-DNA adducts as biomarkers for investigations of tamoxifen-induced endometrial cancer.

Antineoplastic Agents↗
PubMed1999

Ependymomas of the spinal cord and cauda equina: An analysis of 26 cases and a review of the literature.

STUDY DESIGN: Retrospective review. OBJECTIVES: To clarify the clinical features of patients with spinal ependymomas and to compare the clinical results between the patients in whom microsurgical technique and spinal cord monitoring were used intraoperatively and the patients in whom they were not used. SETTING: Keio University Hospital, Tokyo, Japan. METHODS: Twenty-six consecutive patients with spinal ependymomas were treated surgically between 1958 and 1995. All patients underwent tumor resection through a posterior approach. Complete tumor resection was possible in 15 patients (57. 7%), and subtotal tumor resection (more than 90%) was done in two patients (7.7%). Only a partial tumor resection (less than 90%) was performed in the remainder of the patients (34.6%). The operative results of the patients were evaluated by the Japanese Orthopaedic Association Scoring System (JOA score) and its recovery rate. RESULTS: The overall average recovery rate was 18.3%. The mean recovery rate was 14.4% in cervical lesion, 11.1% in thoracic lesion and 40% in lumbar lesion. The recovery rate of eight patients with cervical ependymomas who underwent tumor resection under both microscopic surgical procedure and intraoperative spinal cord monitoring was 37.1% although the recovery rate of the rest of the patients was -1.6%. There was a statistical difference between the two groups (P<0.02). The survival rate of patients following complete excision was statistically better compared to that of patients after incomplete resection. CONCLUSION: Both microsurgical technique and spinal cord monitoring are indispensable to achieve total removal of ependymomas and to obtain improvement of neurological recovery.

Adolescent↗
PubMed1999

Increased carbon monoxide in exhaled air of patients with seasonal allergic rhinitis.

BACKGROUND: Carbon monoxide (CO) can be detected in exhaled air and is increased in asthmatic patients. However, it is uncertain whether exhaled CO is increased in patients with allergic rhinitis. OBJECTIVE AND METHODS: To study whether exhaled CO is increased in patients with allergic rhinitis, exhaled CO concentrations were measured on a CO monitor by vital capacity manoeuvre in 86 patients with seasonal allergic rhinitis during and out of the cedar pollen season. RESULTS: During the season, exhaled CO concentrations were 3. 6 +/- 0.3 p.p.m. and decreased to 1.2 +/- 0.1 p.p.m. out of the season. The values of exhaled CO out of the season were similar to those in age-matched non-smoking healthy control subjects (1.2 +/- 0. 1 p.p.m.). Exhaled CO concentrations were significantly higher in patients with symptoms than in those without symptoms (P < 0.01). Exhaled CO concentrations in patients did not differ significantly among oral and nasal exhalation, and oral exhalation with an expiratory resistance (P > 0.20). CONCLUSION: These findings suggest that allergic rhinitis increases the concentration of CO in exhaled air and increases in exhaled CO may be derived from lower airways.

Adult↗
PubMed1999

Effects of propofol anesthesia on cognitive recovery of patients undergoing electroconvulsive therapy.

The effects of different doses of propofol on post-electroconvulsive therapy (ECT) cognitive recovery were evaluated together with the effects on seizure duration and hemodynamic changes during ECT in 15 depressive patients. Propofol attenuated the increase in arterial blood pressure and heart rate in a dose-dependent manner compared with thiamylal. Propofol showed a clinically significant anticonvulsant effect during ECT in a dose-dependent manner. There were no significant differences among the four different induction groups in the mean recovery time from anesthesia, however, a low dose of propofol suppressed the early recovery of cognitive function. For early cognitive recovery after ECT, a deep anesthetic level is necessary when the traditional ECT apparatus is used which produces sine curve wave stimuli.

Adult↗
PubMed1999

Immunohistochemical finding of alpha-1-antichymotrypsin in tissues of benign prostatic hyperplasia and prostate cancer.

BACKGROUND: Ratio of free to total (F/T) prostate-specific antigen (PSA) is higher in the blood of patients with benign prostatic hyperplasia than those with prostate cancer. To clarify the difference between ratios in these two, alpha-1-antichymotrypsin, the major component of the bound PSA in the blood, was immunohistochemically examined. METHODS: Tissues were obtained surgically via a retropubic approach from patients with benign prostatic hyperplasia (nine cases) and prostate cancer (27 cases). These samples were processed in paraffin blocks, cut into 5 mm sections and stained with antibodies against alpha-1-antichymotrypsin and PSA. RESULTS: The percentage of alpha-1-antichymotrypsin-stained cells in prostate cancer was higher than that in benign prostatic hyperplasia (P<0.05). Almost all of glandular and cancer cells were stained with PSA antibody. The percentage of alpha-1-antichymotrypsin-stained cells in prostate cancer did not correlate to histologic grade, although alpha-1-antichymotrypsin-stained cells were more widely scattered in high grade tissues. No correlation was found between alpha-1-antichymotrypsin-stained cells and ratio of F/T in the blood of cancer patients. In about 20% of cancer tissues, histiocytes with positive alpha-1-antichymotrypsin staining were found in stroma but not in that of benign prostatic hyperplasia. CONCLUSIONS: Prostate cancer tissues are shown to have a richer environment of alpha-1-antichymotrypsin than those of benign prostatic hyperplasia. Some cancer tissues contained alpha-1-antichymotrypsin-stained histiocytes. These local events may correlate to a high amount of the bound form among total PSA in the blood of prostate cancer patients.

Aged↗
PubMed1999

CT examination of the head of the Baikal seal (Phoca sibirica).

We carried out a computerised tomographic (CT) examination to elucidate the modifications in the head related to orbital enlargement in the Baikal seal. Transverse CT images showed that (1) the external frontal contours and the frontal sinuses are compressed medially and ventrally by the orbital enlargement; (2) the caudal part of the nasal cavity and nasopharynx are compacted ventrally; and (3) the cranial cavity is displaced caudally. The neurocranium is obviously separated from the facial part in the transverse plane at the caudal region of the orbit. The disposition of the mandible, zygomatic arch, temporal bone, and the masseter, temporal, digastric and pterygoid muscles is changed by the enlarged orbit in the 3-dimensional reorganisation of the head in this species. It is suggested that adaptation for the Lake Baikal environment primarily resulted in orbital enlargement, and that the altered orbital design may subsequently have influenced the form and function of the masticatory and respiratory system.

Adaptation, Physiological↗