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Biomedical subjects

C Suzuki

Publications and source records attributed to C Suzuki.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Comparison of microfissures between the oval and round window niche areas in human temporal bone].

There are numerous reports on microfissures in the round window niche area, but not many reports have appeared on microfissures in the oval window niche area. In addition, few studies have compared microfissures between the oval and round window niche areas in the same subjects. Hence, the present study investigated the prevalence of microfissures in both areas in human temporal bones. The study was conducted on the 637 ears of 333 cases. Specimens were prepared according to the conventional methods: after fixation, decalcification and dehydration, each specimen was embedded in Celloidin, and the temporal bones were sectioned horizontally at 25-micron intervals. Every 10th section was stained with hematoxylin & eosin, and each section was analyzed under a light microscope. The prevalence of microfissures was analyzed in relation to the sex, left/right differences and age of the subjects. Microfissures were seen in the oval window niche area in 66.2%, and in the round window niche area in 92.0%. When a microfissure was seen in the oval window niche area, it was also detected in the round window niche area in every case. There were no sex or left/right differences in the prevalence of microfissures, and microfissures occurred bilaterally in most cases. The youngest subject with a microfissure in the oval window niche area was a 14-year-old, and the prevalence increased with age up to approximately 60 years. On the other hand, microfissures in the round window niche area were seen in a 3-year-old, and were seen in most cases over the age of ten. These findings suggest that microfissures are more likely to occur in the round window niche area as compared to the oval window niche area. However, the prevalence of microfissures in the oval window niche area was not low either, and it is important to pay attention to both the oval and round niche areas when microfissures are involved in the formation of perilymph fistulae. Given that the prevalence of microfissures in the oval window niche area increased up to about 60 years of age, not only growth, but also mastication, may be involved in the occurrence of microfissures.

Adult↗
PubMed2000

Temporal bone pathology in Wegener's granulomatosis.

This study aimed to demonstrate the temporal bone histopathology of two cases of Wegener's granulomatosis in which the initial symptoms were profound hearing loss and facial nerve palsy respectively. The first case, a woman of 44, suffered profound hearing loss which was remarkably improved by steroid and cyclophosphamide treatment for a time, and which seemed to be caused by invasion from granulation tissue filled in the tympanic cavity. The second case was a 61-year-old woman presenting with the facial nerve palsy. The bony canal of the horizontal portion of the facial nerve was destroyed due to granulation tissue which filled in the tympanic cavity, and granulomatous involvement was observed in the facial nerve. Wegener's granulomatosis can involve the middle ear and/or inner ear, causing hearing loss of conductive, mixed or sensorineural type. Pathogenesis of facial nerve palsy seems to be related to Wegener's granulomatous involvement of facial nerve, because the facial nerve palsy also resolved by using steroid and cyclophosphamide.

Adult↗
PubMed2000

Effects of activin A and follistatin on developmental kinetics of bovine embryos: cinematographic analysis in a chemically defined medium.

The effects of recombinant human activin A and follistatin on the developmental kinetics of bovine presumptive zygotes matured and fertilized in vitro using time-lapse cinematography were investigated. The presumptive zygotes were cultured for 9 days in a chemically defined medium (modified synthetic oviduct fluid, control) and modified synthetic oviduct fluid supplemented with activin A or follistatin. Development under cine-recording conditions was similar to that in an incubator. Addition of activin A to modified synthetic oviduct fluid increased, while addition of follistatin decreased, the percentage of zygotes that developed to morulae and blastocysts. Follistatin significantly prolonged the timing of development to the 9-16-cell stage compared with the control and activin A media. Activin A significantly shortened the duration of the third cell cycle compared with the control, but follistatin significantly prolonged the fourth cell cycle compared with the control and activin A. Developmental arrest ('lag-phase') during the 4-8-cell stage was observed in 95% of embryos developed to more than the 9-16-cell stage in all treatments. The greater the number of cells at the onset of the lag-phase, the earlier the onset of the phase and the shorter the duration of the phase, the further embryos were able to develop by day 9 in all treatments. The number of cells at the onset of the lag-phase in the medium containing activin A was significantly higher than it was in control or follistatin-containing media. Moreover, activin A significantly shortened the duration of the lag-phase compared with follistatin. The present results indicate that activin A may enhance in vitro development of bovine embryos by improving developmental kinetics, especially by increasing the number of cells at the onset of the lag-phase and shortening the duration of this phase.

Activins↗
PubMed1999

Direct detection of endogenous histamine in rat peritoneal mast cells by in-capillary derivatization high-performance capillary electrophoresis.

A simple method for the detection of endogenous histamine in rat peritoneal mast cells was evaluated using on-line mode in-capillary derivatization high-performance capillary electrophoretic (ICD-HPCE) techniques, which were previously developed by our group [S. Oguri et al., J. Chromatogr. A, 787 (1997) 253-260]. The method involves a suspension of peritoneal mast cells (1 x 10(6) cells/ml of saline) collected from a male Wistar rat (eight weeks of age), which are directly introduced into the capillary tube from the anodic end by hydrostatic injection (at 25 cm height, for 2-20 s). When a high-voltage potential (25 kV) is applied to the capillary, which is already filled with the run buffer containing both a lysing reagent (SDS, sodium dodecyl sulfate,) and a derivatizing reagent (OPA, o-phthalaldehyde; NAC, N-acetylcysteine), histamine in the mast cells was detected at high-sensitivity level without further procedures. During ICD-HPCE, the mast cells injected in the capillary were lysed with the lysing reagent, free histamine released from the cell was labeled with the derivatizing reagent, and its derivative was electromigrated, separated and detected with a fluorescence detector (excitation wavelength at 340 nm, emission wavelength at 450 nm) in a fused-silica capillary (75 cm x effective length x 50 microm I.D.). The run buffer used was a 20 mM phosphate-borate buffer (pH 10) containing 20 mM SDS, 2 mM OPA and 2 mM NAC. This method was also examined with regard to the possibility of its use for determination of histamine at the single mast cell level.

Animals↗
PubMed1999

Open sandwich ELISA with V(H)-/V(L)-alkaline phosphatase fusion proteins.

The Sandwich ELISA is a widely used technique to measure antigen concentration. Recently, a novel ELISA based on the interchain interaction of separated V(H) and V(L) chains from a single antibody variable region (Fv) was proposed (Open Sandwich ELISA). Since it employs a single antibody recognizing one epitope, the assay requires, in essence, only one cycle of incubation and washing steps. To demonstrate this directly, we have constructed a recombinant gene fusion encoding the V(H) chain of an anti-hen egg lysozyme (HEL) antibody HyHEL-10 and Escherichia coli alkaline phosphatase (V(H)-PhoA). The same type of gene fusion using V(L) chain instead of V(H) chain (V(L)-PhoA) was also constructed and the proteins were obtained with an E. coli expression/secretion system. Open Sandwich ELISAs were performed using microtiter plates with immobilized V(L) or V(H) fragment, and V(H)-PhoA or V(L)-PhoA, respectively, as the detection reagent which was simultaneously added to each well with samples. As a result, HEL concentrations in the samples were determined after one round of incubation and washing steps, with a signal generated in a direct relationship to the concentration of HEL added to the reaction mixture. The minimum detectable HEL concentration was approximately 10 ng/ml, which was almost equal to the value previously obtained with plate-immobilized V(L) and V(H) fragment displayed on M13 phage. When the active-site mutant V(H)-PhoA(D101S) was employed instead of V(H)-PhoA and reacted at an optimum pH of 10, a significant enhancement in signal was attained.

Alkaline Phosphatase↗
PubMed1999

Secretion of a protoxin post-translationally controlled by NaCl in a halotolerant yeast, Pichia farinosa.

The halotolerant yeast, Pichia farinosa KK1 secretes a killer toxin consisting of alpha (6.3 kDa) and beta (7.8 kDa) subunits, produced from a chromosomally encoded preprotoxin. In the presence of a high concentration of NaCl, a 26-kDa glycoprotein (gp26) that reacted with anti-beta-subunit antiserum was found to be secreted into the medium. Amino acid sequence analysis confirmed that gp26 is a protoxin generated by removal of the signal peptide from the preprotoxin. The purified gp26 did not have killer activity, suggesting that further processing is necessary for acquisition of this activity. Secretion of gp26 increased with increasing concentrations of NaCl in the medium and maximum secretion was observed at 2 M NaCl. Western blot analysis and RT-PCR showed that the secretion of gp26 is post-translationally controlled by NaCl.

Amino Acid Sequence↗
PubMed1999

P-type ATPase spf1 mutants show a novel resistance mechanism for the killer toxin SMKT.

SMKT, a killer toxin produced by the halotolerant yeast Pichia farinosa KK1, consists of alpha and beta subunits with folding remarkably similar to that of the fungal killer toxin KP4, a Ca2+ channel inhibitor. The budding yeast Saccharomyces cerevisiae is sensitive to SMKT. To understand the killing mechanism of SMKT, we isolated SMKT-resistant mutants of S. cerevisiae and characterized them. Five spf mutants (sensitivity to the P. farinosa killer toxin) fell into a single genetic complementation group, designated spf1. The SPF1 gene was cloned by complementation of the mutant phenotype. The SPF1 gene encodes a putative P-type ATPase of 1215 amino acid residues that contains 12 membrane-spanning regions. Gene disruption revealed that the SPF1 gene is not essential for viability but is required for the sensitivity to SMKT. The spf1 disruptant showed some phenotypes characteristic of glycosylation-defective mutants and secreted underglycosylated invertase. Fluorescence-activated cell-sorting analysis and indirect immunofluorescence microscopy showed that SMKT interacts with the cell surface of the resistant cells but not with that of sensitive cells, suggesting a novel resistance mechanism for this toxin. The glycosylation-defective phenotype and possible killer-resistant mechanisms are discussed in comparison with the Golgi Ca2+ pump Pmr1p.

ATP-Binding Cassette Transporters↗
PubMed1999

Twin-to-twin transfusion syndrome with hydrops: a retrospective analysis of ten cases.

We retrospectively studied 10 cases of twin-to-twin transfusion syndrome (TTTS) with fetal hydrops. TTTS was diagnosed sonographically between the 17-31 weeks of gestation. All twins were delivered by emergency cesarean section because of cardiac decompensation of one or both fetuses. The mean (+/-SD) age at diagnosis was 26.1 +/- 4.5 and the mean age at delivery was 28.8 +/- 2.0 weeks. Gestational age at birth was similar in survivors and nonsurvivors. However, surviving infants were diagnosed later in gestation (23.6 +/- 4.8 vs. 28.7 +/- 1.9 weeks; p < 0.01); and gestational age at appearance of hydrops were later in survivors (26.1 +/- 3.2 vs. 29.2 +/- 2.4 weeks; p < 0.05). Overall survival rate was 50% (10 of 20 infants). All survivors were delivered within 3 days after the appearance of fetal hydropic changes. Extrauterine treatment in earlier stages of TTTS might improve the outcome. Nevertheless, more aggressive intrauterine treatment should be considered in the most severe cases of TTTS developing before 24-25 weeks' gestation.

Cesarean Section↗
PubMed1999

Characterization of the epitope on murine T-cell receptor (TCR) alpha proteins recognized by H28-710 monoclonal antibody.

Antigen recognition by alphabeta T lymphocytes is mediated via the multisubunit T-cell receptor (TCR) complex consisting of invariant CD3-gamma,delta,epsilon, and zeta chains associated with clonotypic TCRalpha,beta molecules. In the current report, we evaluated the molecular basis for recognition of murine TCRalpha proteins by H28-710 monoclonal antibody (MAb), specific for the constant region of murine TCRalpha chains. H28-710 is widely used in the study of the TCR complex as it is the only reagent currently available that recognizes all murine TCRalpha proteins, regardless of their clonotype. These data show that H28-710 is useful for the immunoprecipitation of TCRalpha proteins not associated with CD3 subunits, and that H28-710 effectively recognizes denatured TCRalpha proteins synthesized in several different cell types. Most importantly, these results demonstrate that H28 binding involves a serine/threonine-rich region between amino acids 150-177 on murine TCRalpha polypeptides.

Amino Acids↗
PubMed1999

Prevalence of maternal cytomegalovirus (CMV) antibody and detection of CMV DNA in amniotic fluid.

The prevalence of cytomegalovirus (CMV) IgG antibody was determined in 573 pregnant women in the first trimester. The overall prevalence of CMV IgG antibody was 77.5%. The rate of seropositivity was 67.7% in women < 25 yr, and increased with age to 85.7% in women 40 yr. These results imply that young women in Japan are at increased risk for primary CMV infection during pregnancy and that congenital CMV infection rates might increase in the future. We conducted a prospective study of 75 pregnant women who underwent amniocentesis for various indications to determine if CMV DNA could be detected in the amniotic fluid. None had symptoms associated with CMV infection, CMV IgM antibody, or seroconversion to CMV IgG antibody during pregnancy. CMV DNA was not detected in the amniotic fluid using a polymerase chain reaction assay. The 65 fetuses, including 3 sets of twins, were followed through birth. CMV DNA was not detected in urine samples obtained within the first 2 weeks of life. In conclusion, CMV DNA was not detected in the amniotic fluid of women who did not have CMV infection. These results, however, suggest that the negative predictive value of prenatal amniotic fluid analysis is high and that the presence of CMV DNA in the amniotic fluid has clinical significance for the diagnosis of congenital CMV infection if detected in pregnant women.

Adult↗
PubMed1999

Inflammatory response to chronic otitis media in DiGeorge syndrome: a case study using immunohistochemistry on archival temporal bone sections.

Immunohistochemical analyses were conducted on archival celloidin-embedded human temporal bone sections from an 8-month-old boy with chronic otitis media and DiGeorge syndrome. We employed antigen retrieval methods with saturated sodium hydroxide-methanol solution, microwave incubation, and proteolytic treatment to demonstrate the distribution of T-lymphocytes, B-lymphocytes, macrophages, and intercellular adhesion molecule 1 (ICAM-1) expression in the middle ear. B-lymphocytes and macrophages were observed predominantly within the middle ear mucosa. T-lymphocytes were rare. Further, ICAM-1 was expressed in the vascular endothelium of the lamina propria, as well as infiltrating mononuclear cells. This suggests that the expression of ICAM-1 can be induced in the middle ear with otitis media, even if T-lymphocytes are depressed in a cell-mediated immunodeficiency disorder such as DiGeorge syndrome.

Antibodies, Monoclonal↗
PubMed1999

Distribution of psammoma bodies in the internal auditory canal and its extended areas in the human temporal bone.

The internal auditory canal (IAC) and its extended areas of 27 normal human temporal bone specimens were investigated histologically for the distribution of psammoma bodies. A total of 145 +/- 25 (mean +/- SE) psammoma bodies were counted in series of every tenth 30-microm-thick section. Psammoma bodies were observed in the IAC and around the labyrinthine portion of the facial nerve (FN), the geniculate ganglion of the FN, and the posterior ampullary nerve in the singular canal. The number of psammoma bodies increases with age. We believe that psammoma bodies are a normal finding of aging in the IAC. The compression of the FN by psammoma bodies in the labyrinthine portion of the facial canal and the distribution of numerous psammoma bodies surrounding the posterior ampullary nerve in the narrow singular canal raise the questions of the involvement of psammoma bodies in the FN and in vestibular dysfunction and the presence of psammoma bodies in the subarachnoid space.

Adolescent↗
PubMed1999

[Genoepidemiology and pathogenicity of TT virus in Japanese men with history of intravenous drug abuse and tattoo].

Blood contamination has been proposed as TTV transmission. We studied the genoprevalence of TTV in Japanese men with history of intravenous drug abuse and/or tattoo. TTV was identified in serum by a polymerase chain reaction. TTV was detected in 89.7 percent of the men with history of intravenous drug abuse and/or tattoo, 74.4 percent of chronic hepatitis C patients, 78.0 percent of the chronic hepatitis B, and 65.8 percent of chronic hepatitis nonB nonC patients. Serum ALT levels of those infected with TTV alone were 27.2 +/- 17.5 IU/L. In the patients with chronic hepatitis C, serum ALT levels of those coinfected with TTV were similar to serum ALT levels of those without TTV infection. These results suggest that TTV causes no or mild hepatitis.

DNA Virus Infections↗
PubMed1999

Esthetic replacement of a maxillary central incisor with an ITI 15-degree angled implant: a case report.

Single-stage implants are frequently used, but their use in the anterior dentition has not been widely published. The purpose of this case report is to present the esthetic result of a single-stage implant to replace a maxillary central incisor, and to demonstrate the unconventional use of a 15-degree angled ITI implant. A 15-degree 12-mm hollow cylinder was placed with the angle reversed facially. The emergence profile of the adjacent roots was matched with the transmucosal portion, turning at the osseous crest. The implant was restored after 6 months with an ITI gold coping and transverse screw-retained crown. The gingival margin and the papillae were shaped by the transmucosal portion and the restoration. To date, the implant has been loaded for 24 months with an ideal soft tissue esthetic and radiographic appearance.

Adult↗
PubMed1998

A recurrent nonrandom translocation (3;7)(q27;p12) associated with BCL-6 gene rearrangement in B-cell diffuse large cell lymphoma.

Two cases of B-cell diffuse large cell lymphoma associated with the t(3;7)(q27;p12) and BCL-6 rearrangement are described. Cytogenetic studies revealed [case 1] 47,XY,t(3;7)(q27;p12),+12 and [case 2] 45,X,-Y,t(3;7)(q27;p12),del(6)(q21q25),+16,-21. The translocation of each case had a non-random chromosomal change involving a 3q27 locus associated with BCL-6 gene rearrangement identified by Southern blot analysis. Both cases involved multiple lymph nodes and extranodal regions, such as stomach and peritoneal cavity in case 1, extranodal retroperitoneal space, subcutis, probable liver, and colon in case 2. Chemotherapy provided only short survival after onset: 17 and 16 months, respectively. Altered expression of adhesion molecules CD44, CD54 (case 1) and CD11a and CD18 (case 2) may help to explain the poor outcome of these patients.

Aged↗