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Biomedical subjects

H Seki

Publications and source records attributed to H Seki.

At least 19 recordsLinked to original sources
PubMed2004

Immunohistochemical localization of cyclooxygenase-1 and -2 in synovial tissues from patients with internal derangement or osteoarthritis of the temporomandibular joint.

This study examined the immunohistochemical expression and localization of cyclooxygenase-1 and -2 (COX-1 and COX-2) in synovial tissues from patients with internal derangement (ID) or osteoarthritis (OA) of the temporomandibular joint (TMJ). Synovial tissues from patients with condylar fractures of the mandible were studied as control. Synovial tissues from 13 TMJs of 10 patients with ID or OA and from 5 TMJs of 4 patients with fractures were examined for COX-1 and COX-2 expression by immunohistochemical staining using two monoclonal antibodies. In addition, whether the COX-2 expression grade correlated with the synovitis score and clinical findings was assessed. COX-2 was expressed in the synovial lining, infiltrating mononuclear cells, fibroblast-like cells, and blood vessels, including CD31-positive endothelial cells, in the synovium of patients with ID or OA. Expression levels of COX-1 in synovial lining cells and endothelial cells were similar in the specimens obtained from the patients with ID or OA and those obtained from the controls. The expression of COX-2 positively correlated with arthroscopic findings of synovitis (p = 0.55, P = 0.023) and with joint pain (p = 0.56, P = 0.021). These results suggest that up-regulation of COX-2 in synovium may play a part in the pathogenesis of synovitis in patients with ID or OA of the TMJ.

Adult↗
PubMed2003

Formant interaction as a cue to vowel perception: a case report.

Accumulating evidence indicates that cerebral processing of consonants and vowels is separable. It has been shown that disordered temporal acuity leads to disturbed consonant perception in cases with pure word deafness. In contrast, there has been no clear explanation of how vowel perception is impaired. We examined a patient with auditory agnosia, who showed a differential ability to identify the five Japanese vowels after bilateral cerebral lesions. He correctly identified the vowel [a] in more than 70% of auditory presentations, whereas he identified [i] in only about 30% of presentations. The difference between the first and second formant frequencies "F2-F1" and an artificially defined value "F1-(F2-F1)" for each vowel correlated significantly with the percentage of correct identifications. These findings support the hypothesis that vowel perception is based on formant interactions.

Adult↗
PubMed2002

Long-term treatment with nicardipine for severe pre-eclampsia.

OBJECTIVE: To evaluate the safety of long-term nicardipine treatment in severely pre-eclamptic women and their fetuses/newborns. METHODS: We divided 50 pregnant women into three groups according to the length of their treatment: short-term treatment of severely pre-eclamptic women (7 days or less, n=20); medium-term treatment also of severely pre-eclamptic women (8-28 days, n=20); and long-term treatment of women with severe superimposed pre-eclampsia (29 days or more, n=10). RESULTS: Nicardipine significantly lowered both systolic (P<0.01) and diastolic blood pressures (P<0.025) in all three groups. The incidence of delivery before 28 weeks of gestation was very low in all three groups. There were no maternal or fetal/neonatal adverse effects. CONCLUSION: Our results suggest that long-term treatment with nicardipine for severe pre-eclampsia is as effective and safe as a short- and medium-term treatment.

Adult↗
PubMed2001

Oxindole derivatives as orally active potent growth hormone secretagogues.

A series of substituted oxindole derivatives was synthesized and evaluated for growth hormone (GH) releasing activity using cultured rat pituitary cells. (+)-6-Carbamoyl-3-(2-chlorophenyl)-(2-diethylaminoethyl)-4-trifluoromethyloxindole (SM-130686, 37S) was found to have potent activity (EC(50) = 3.0 nM), while the other enantiomer 37R had reduced activity. The absolute configuration of 37S was confirmed by X-ray crystallographic analysis. Compound 37S showed a good pharmacokinetic profile in rats with 28% oral bioavailability at 10 mg/kg and excellent in vivo activity as evidenced by a significant weight gain after 4 days of oral administration at 10 mg/kg twice a day. Compound 37S displaced the binding of (35)S-MK-677 to human GHS-R with an IC(50) value of 1.2 +/- 0.2 nM.

Administration, Oral↗
PubMed2001

Differential cellular targets of Epstein-Barr virus (EBV) infection between acute EBV-associated hemophagocytic lymphohistiocytosis and chronic active EBV infection.

Unusual Epstein-Barr virus (EBV) infection into T or natural killer cells plays a pivotal role in the pathogenesis of acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV). The precise frequency and localization of EBV genome in lymphocyte subpopulations especially within T-cell subpopulations are unclear in these EBV-related disorders. This study analyzed the frequency of EBV-infected cells in circulating lymphocyte subpopulations from 4 patients with acute EBV-HLH and 4 with CAEBV. EBV- encoded small RNA-1 in situ hybridization examination of peripheral blood lymphocytes showed a significantly higher frequency of EBV-infected cells of 1.0% to 13.4% in EBV-HLH and 1.6% to 25.6% in CAEBV, respectively. The patterns of EBV infection in lymphocyte subpopulations were quite different between acute EBV-HLH and CAEBV. EBV infection was predominant in CD8(+) T cells in all EBV-HLH patients, whereas the dominant EBV-infected cell populations were non-CD8(+) lymphocyte subpopulations in CAEBV patients. Phenotypical analysis revealed that EBV-infected cell populations from both EBV-HLH and CAEBV were activated. There was no predominance of any EBV substrain of latent membrane protein-1, EBV-associated nuclear antigen (EBNA)-1, and EBNA-2 genes between the 2 abnormal EBV-associated disorders, and self-limited acute infectious mononucleosis. These results showing differential virus-cell interactions between acute EBV-HLH and CAEBV indicated different pathogenic mechanisms against EBV infection between the 2 EBV-associated diseases, which accounts for the difference in clinical manifestations between the 2 diseases.

Acute Disease↗
PubMed2001

Mutation frequencies of EXT1 and EXT2 in 43 Japanese families with hereditary multiple exostoses.

Hereditary multiple exostoses (EXT) is an autosomal dominant bone disease characterized by the formation of cartilage-capped prominences. EXT is genetically heterogeneous with at least four chromosomal loci. Among the four loci, the exostosis type 1 gene (EXT1) and type 2 gene (EXT2) have been cloned. Previous studies have shown that disease-type-specific frequency of mutations is different among various ethnic populations. To determine those frequencies in the Japanese, we conducted a large-scale mutation screening on both genes. In 23 of 43 Japanese families examined, we found 21 different mutations, of which 18 are novel. Seventeen (40%) of the 23 families had a mutation in EXT1 and six (14%) had a mutation in EXT2, suggesting that the former mutations are more frequent than the latter in Japanese EXT families. Of the 17 families with EXT1 mutations, 13 had those causing premature termination of the EXT1 protein and four showed missense mutations, whereas five of the six families with EXT2 mutations had those causing premature termination and one showed missense mutation. Interestingly, all four EXT1 missense mutations occurred in an arginine residue at codon 340 (R340) that is known as a critical site for expression of heparan sulfate glycosaminoglycans, suggesting that the region encompassing the arginine residue may play an important role in the function of the EXT1 protein. These results expand our knowledge of the ethnic difference of EXT and the structure-function relationship of the EXT genes.

DNA↗
PubMed2001

Solitary thyroid metastasis of renal clear cell carcinoma: report of a case.

A case of solitary thyroid metastasis of renal clear cell carcinoma is described. The patient was a 77-year-old Japanese woman, who was referred to our department after a thyroid tumor was identified in May 1999. She had a history of renal clear cell carcinoma of the left kidney, which had been partially resected 3 years previously. Ultrasound sonography demonstrated that a well-demarcated hypoechoic mass containing high-echo spots representing small calcifications, which measured 45 x 34 x 31 mm in size, occupied the left lobe. Computed tomography revealed a low-density mass containing small calcifications. The results of preoperative fine-needle aspiration cytology strongly suggested a clear cell carcinoma metastasizing to the thyroid. A left hemithyroidectomy was performed on July 27, 1999. A histological examination revealed that the neoplasm was composed of tumor cells with abundant clear cytoplasm and round nuclei. The histological characteristics of this thyroid tumor were virtually identical to the renal cell carcinoma resected 3 years previously. Thyroglobulin stained negatively in the clear cells of the resected thyroid tumor in an immunohistochemical analysis. Clinically, the thyroid gland is a rare site of tumor metastasis; however, we should also consider the possibility of metastasis in the case of thyroid tumor patients with a history of renal cell carcinoma.

Aged↗
PubMed2001

Spontaneous esophageal perforation related to a duodenal ulcer with pyloric stenosis: report of a case.

This report describes a case of spontaneous esophageal perforation that was considered to be etiologically related to a duodenal ulcer with pyloric stenosis. The patient was a 54-year-old Japanese man who presented following the sudden onset of severe abdominal pain and dyspnea after an episode of vomiting. He had a history of duodenal ulcer. Computed tomography revealed an extremely dilated stomach containing abundant food residue, intraabdominal effusion, bilateral pleural effusion, and mediastinal emphysema, findings that strongly suggested esophageal perforation. Esophagoscopy confirmed perforation of the lower esophagus. Laparotomy revealed marked contamination, including food residue in the abdominal cavity, and a severely dilated stomach attributed to pyloric stenosis caused by a duodenal ulcer. A 2-cm longitudinal perforation was found on the right side of the lower esophagus. Because the patient's general condition was too poor to tolerate a one-stage operation (primary closure of the perforation, gastrectomy, and reconstruction), we initially performed decompression gastrostomy and control of the esophageal leakage with T-tube placement. Following the T-tube was removed 1 month later, distal gastrectomy and reconstruction of the gastrojejunostomy (Billroth II method) could be safely performed.

Digestive System Surgical Procedures↗
PubMed2001

Immunohistochemical localization of inducible nitric oxide synthase in synovial tissue of human temporomandibular joints with internal derangement.

The expression and distribution of inducible nitric oxide synthase (iNOS) was examined in 12 samples of human temporomandibular joint (TMJ) with internal derangement (ID) and four control specimens. In the diseased joints, strong or definite iNOS reactivity was expressed in synovial lining and endothelial cells; weaker activity was present in synovial fibroblasts. In contrast, although there was weak expression of iNOS in synovial fibroblasts and endothelial cells in the two control specimens, there was no iNOS staining in the synovial lining cell layers. This original report that iNOS is expressed in the synovial tissue of the temporomandibular joint indicates that nitric oxide is produced locally at least in the synovial lining in these joints when affected by internal derangement.

Adolescent↗
PubMed2001

Molecular cloning and functional analysis of pea cDNA E86 encoding homologous protein to hypersensitivity-related hsr203J.

Clone E86 was isolated as cDNA for elicitor-inducible gene from pea epicotyls by differential screening. The deduced amino acid sequence of E86 showed high homology to hypersensitivity-related protein hsr203J in tobacco and also showed significant homologies to the Ser-active hydrolases, such as mammalian hormone-sensitive lipases, bacterial lipases and esterases. E86 polypeptide possesses consensus amino acid sequence motifs (His-Gly) and (Gly-X-Ser-X-Gly) conserved in lipases and esterases and showed esterase degradation of p-nitrophenyl butyrate. Northern blot analysis revealed that the E86-transcript is abundant in roots and stems and was induced by fungal elicitor in pea epicotyls. However, elicitor-induced accumulation of E86 mRNA was significantly inhibited by the fungal suppressor. Furthermore the expression of the genes encoding E86 and phenylalanine ammonia-lyase was induced within 1 h after the inoculation of a nonpathogen, but it was delayed for 5 h by the inoculation of a compatible pathogen. These results suggest that the elicitor-induced Ser-active hydrolase derived from E86 gene might be related to the plant defense responses.

Journal Article↗
PubMed2001

Cloning and expression of the ferredoxin gene from extremely halophilic archaeon Haloarculajaponica strain TR-1.

The gene encoding a ferredoxin (Fd) from Haloarculajaponica strain TR-1 was cloned and sequenced. Sequence analysis of the cloned Ha. japonica Fd gene revealed that the structural gene consisted of an open reading frame of 387 nucleotides encoding 129 amino acids. The deduced amino acid sequence of Ha. japonica Fd showed 84 to 98% identity with corresponding sequences in other extremely halophilic archaea. The Ha. japonica Fd gene was inserted into the shuttle vector pWL102 and used to transform Ha. japonica. Ha. japonica Fd could then be produced as a fusion with His-Tag (6xHis) in Ha. japonica host cells. The absorption and ESR spectra of the Fd/His Tag fusion protein revealed the presence of a [2Fe-2S] cluster which is characteristic of native Ha. japonica Fd.

Amino Acid Sequence↗
PubMed2001

Cytotoxic effects of soluble factor in preeclamptic sera on human trophoblasts.

Evidence indicating abnormal biological behavior of trophoblasts has been seen in preeclamptic patients, but the mechanism is still unknown. We have previously shown that endothelial injury and neutrophil activation are induced by certain factors in preeclamptic sera. We investigated the effect of sera from eight preeclamptic and 11 normal pregnant women on cellular proliferation and viability of trophoblasts using 3H-thymidine incorporation and the trypan-blue dye exclusion test, respectively. Five of eight preeclamptic sera, but none of the normal pregnant sera, inhibited 3H-thymidine incorporation. The trypan-blue test revealed the sera reduced cellular viability. Gel permeation showed that the greatest growth-inhibitory activity corresponded to a molecular weight of 50 kDa. The serum-mixing test revealed this permeation and inhibitory preeclamptic sera suppressed the growth-promoting activity of normal pregnant sera in a dose-dependent manner. These results suggested the presence of certain factors in some preeclamptic sera that can affect cellular behavior of human trophoblasts.

Adult↗
PubMed2001

Effect of the reducing agent on the oxygen-inhibited layer of the cross-linked reline material.

The purpose of this study was to clarify the effect of the reducing agent on the oxygen-inhibited layer of the cross-linked reline material. A commercial autopolymerizing reline resin containing 1,6-hexanediol dimethacrylate as cross-linking agent and 1 wt.% sodium sulphite solution as a reducing agent was prepared. The inhibited layer was observed using an optical transmission microscope under the conditions of the application of sodium sulphite for 0, 1, 5 and 15 min after curing for 10 min in air. As a control, the reline material was cured on sealing from air. Moreover, the three-point flexural strength test was performed under the same conditions. The fracture was then observed using scanning electron microscopy (SEM). Although hardness of the inhibited layer was enhanced after the application of the reducing agent, the layer was still observed. The flexural strength of the control and the groups after application of the reducing agent was significantly higher than the group without reducing agent. SEM examination revealed many polymer beads on the group without reducing agent, whereas polymer beads could not be observed on the groups applying the reducing agent. These results indicated that the application of sodium sulphite was effective in hardening the surface unpolymerized zone.

Analysis of Variance↗
PubMed2001

Cytoprotective role of heme oxygenase (HO)-1 in human kidney with various renal diseases.

BACKGROUND: We previously reported that glomerular changes in the renal specimen of a human case with heme oxygenase-1 (HO-1) deficiency were mild, but tubulointerstitial injury advanced progressively. This study examined the patterns of HO-1 production in the kidney in various renal diseases. Furthermore, the critical cytoprotective roles of HO-1 were evaluated in the kidney by comparing HO-1 production and expressions of carboxymethyllysine (CML) and pentosidine, both of which are markers of oxidative stress. METHODS: Renal biopsy or autopsy materials were obtained from a total of 74 patients. Degrees of hematuria and proteinuria and the levels of urinary N-acetyl-beta-D-glucosaminidase (NAG), beta2-microglobulin (beta2m), and creatinine were evaluated. Immunohistochemical studies for HO-1, CML, and pentosidine expressions were performed with their specific antiserum. RESULTS: HO-1 staining was observed within tubular epithelial cells in all of the renal diseases, but was not detected within intrinsic glomerular cells. HO-1 staining tended to be more intense within distal tubuli than in proximal tubuli. Within distal tubuli, there was no significant correlation between intensity of HO-1 staining and degree of hematuria or presence of proteinuria. Within proximal tubuli, HO-1 staining tended to be more intense with greater degrees of hematuria, presence of proteinuria, and moderate tubulointerstitial damage. Intense staining of CML and pentosidine was observed within renal tubular epithelial cells only in HO-1-deficient patients. CONCLUSIONS: HO-1 plays important roles in protecting renal tubuli from oxidative injuries, as these cells are constantly exposed to various oxidative stresses. It is suggested that renal tubular epithelia are more susceptible to oxidative stress due to the lack of this critical enzyme in HO-1 deficiency.

Adolescent↗
PubMed2001

The 'superficial' peroneal artery: a variation in cutaneous branching from the peroneal artery, nourishing the distal third of the leg.

Two different vascular patterns were encountered in cutaneous branches from the peroneal artery to the posterolateral aspect of the distal third of the leg in 22 flaps from 22 patients who underwent cutaneous or osteocutaneous peroneal flap surgery. In the type 1 vascular pattern, a branch from the peroneal artery, named the 'superficial peroneal artery', nourished the posterolateral aspect of the leg by splitting into several septocutaneous branches. In the type 2 pattern a few septocutaneous branches originated directly from the main peroneal artery and nourished the same area as that fed by the type 1 branch. The type 1 vascular pattern has not been reported to date but was seen in nine out of the 22 consecutive peroneal flaps. The superficial peroneal artery, with its considerable vascular diameter, may serve as a recipient vessel for free flaps or may serve as a donor nutrient vessel for a cutaneous flap, which can be transferred without sacrificing the main peroneal artery. Awareness of these two vascular patterns in the distal third of the leg should also help to reduce the small percentage of skin-flap failures that occur when the cutaneous or osteocutaneous peroneal flap is used.

Adult↗