Biomedical subjects

N Suzuki

Publications and source records attributed to N Suzuki.

At least 127 records · Page 7Linked to original sources

PubMed2001

Increased urinary leukotriene E4 excretion in patients with atopic dermatitis.

BACKGROUND: Synthesis of cysteinyl leukotrienes (LTs) is known to play a part in the pathogenesis of inflammatory diseases. OBJECTIVES: To define the involvement of cysteinyl LTs in atopic dermatitis (AD). METHODS: Synthesis of cysteinyl LTs was assessed in patients with AD and healthy volunteers by measuring urinary LTE4, a useful index of systemic cysteinyl LT synthesis, using liquid chromatography/tandem mass spectrometry. RESULTS: Mean +/- SD urinary LTE4 levels in patients with AD (125 +/- 69 pg mg(-1) creatinine, n = 20) were significantly higher (P < 0.01) than in healthy volunteers (60 +/- 19 pg mg(-1) creatinine, n = 17). A significant correlation between urinary LTE4 and total serum IgE levels in patients with AD was observed (r = 0.643, P < 0.05). CONCLUSIONS: Our findings demonstrate an enhanced synthesis of cysteinyl LTs in patients with AD and suggest that cysteinyl LTs are involved in the pathophysiology of AD.

Adolescent↗

PubMed2001

Progression of prostate cancer to neuroendocrine cell tumor.

BACKGROUND: The progression to endocrine therapy-resistant prostate cancer is partly due to clonal change to neuroendocrine cell tumor. To elucidate this pathologic process, the clinical courses of four cases of neuroendocrine cell tumor that were found at autopsy are reported. METHODS: Between 1995 and 1999, autopsies were performed for 20 cases of prostate cancer. Lesions predominantly composed of a neuroendocrine cell tumor (small cell carcinoma) were found in four men. The clinical courses of these cases were compared to 16 other non-neuroendocrine cell tumors (adenocarcinomas). RESULTS: The outstanding features of the neuroendocrine cell tumors were: (i) survival was brief after relapse, although the duration of control by employing endocrine therapy varied; (ii) the prostate-specific antigen level did not increase after relapse; and (iii) the sites of metastasis were similar to those of common adenocarcinomas. CONCLUSION: The progression to a neuroendocrine cell tumor indicated a poor prognosis and slight (if any) changes in the serum prostate-specific antigen level. This tumor might not appear to respond to any therapeutic attempt.

Aged↗

PubMed2001

A new method for removal of albumin-binding uremic toxins: efficacy of an albumin-dialysate.

It is difficult for conventional hemodialysis to remove albumin-binding uremic toxins (ABUTs) even though they are low molecular weight substances. We investigated the efficiency of albumin-dialysate (AD) for removal of ABUT. Phenols and indoxyl sulfate were selected as ABUT. In vitro dialysis was performed for 2 h in the closed circuit with ABUT containing plasma as a test solution using conventional dialysate (CD) or AD. By the use of CD, the ABUT concentration in the test solution only was reduced by 20 to 30%. On the other hand, AD caused a marked reduction and an increase in test solution and dialysate concentration of ABUT, respectively. ABUT in AD could be adsorbed effectively by activated-charcoal column; accordingly, the ABUT concentration in the test solution continued to decrease throughout the study period. These results suggest that AD could remove ABUT more efficiently than CD, and AD may be useful for reducing accumulated ABUT levels.

Dialysis Solutions↗

PubMed2001

Ultrastructural studies of Sarcocystis cruzi (Hasselmann, 1926) Wenyon, 1926 infection in cattle (Bos taurus): Philippine cases.

This paper documents the first report of Sarcocysti s cruzi infection in domesticated cattle (Bos taurus) in the Philippines. Fusiform-shaped microscopic sarcocysts (183-578 microns long and 20-98 microns wide) with distinct septae were found in the skeletal, striated and heart muscle. The sarcocyst wall or parasitophorous vacuolar membrane, 1.37-2.75 microns thick consisted of closely-packed villar protrusions 80-400 nm in dm. Middle and distal segments of VP were bent approximately 90 degrees parallel to the cyst wall surface. The villar core lacked microtubules, and at some points, the distal ends of the VP collectively formed conical tufts. Primary cyst wall had numerous 70-100 nm bubble-like undulations, and the ground substance was 0.25-0.5 micron in thickness. The ultrastructure of S. cruzi cyst wall typifies the Type 7 sarcocyst wall, and bears close similarities with the Philippine and the Vietnam strain of bubaline Sarcocystis levinei.

Animals↗

PubMed2001

Inflammatory pseudotumor of the liver: case report and review of the literature.

Inflammatory pseudotumor is a rare lesion that generally is considered to be benign in biological behavior, although some may recur or metastasize. The authors report on a patient with inflammatory pseudotumor of the liver whose preoperative radiologic findings resembled those of focal nodular hyperplasia. The biological investigation showed a polyclonality of the cells and diploidy of the DNA content and suggested benign characteristics of the lesion. J Pediatr Surg 36:663-666.

Angiography↗

PubMed2001

Magnetic resonance angiography of portal collateral pathways after hepatic portoenterostomy in biliary atresia: comparisons with endoscopic findings.

BACKGROUND/PURPOSE: This study was undertaken to assess the usefulness of magnetic resonance angiography (MRA) in detecting varices and to investigate the possibility of avoiding routine endoscopy after surgery for biliary atresia (BA). METHODS: The subjects are 21 patients who have undergone periodical MRA since 1996. The esophageal and gastric vessels were investigated as the sites of potential development of collateral vessels. The collateral vessels on MRA were compared with endoscopic findings. RESULTS: (1) Detection of collateral vessels: of 21 patients examined, 9 patients had 12 varices. MRA depicted collateral vessels in all of the 12 varices (sensitivity, 100%). However, all MRA findings, but one was compatible with endoscopic findings (specificity, 92.9%). Outside of a series of these 21 patients, there were 3 additional patients who had undergone endoscopic treatments previously with success, and in whom esophageal vessels were not depicted on MRA, but endoscopy showed remnant varices. (2) Time-dependent relationship between the appearance of collateral vessels and varices: of 4 varices that appeared after the start of MRA, 3 esophageal varices were found endoscopically simultaneously with or after delineation of collateral vessels on MRA. In the remaining patient, varices were found enodscopically 6 months before the MRA delineation, because a simultaneous MRA was not performed in this case. All these varices were in the early stage. CONCLUSIONS: MRA was highly sensitive and specific in detecting esophagogastric collateral vessels of the portal venous system. An endoscopic examination is unnecessary until collateral vessels are seen on MRA after surgery for BA.

Biliary Atresia↗

PubMed2001

Results of bowel plication in addition to primary anastomosis in patients with jejunal atresia.

BACKGROUND/PURPOSE: Disturbed intestinal transit (DIT) associated with bowel dilation occurs in some postoperative patients with jejunal atresia. Bowel plication (BP) has been introduced to prevent the DIT, but the long-term results of BP are unclear. METHODS: The authors reviewed the preoperative and operative records and postoperative clinical courses (for 2.3 to 7.0 years; mean period, 3.7 years) of 19 jejunal atresia patients, 4 of whom had undergone additional BP with primary anastomosis after dilated bowel resection or tapering jejunoplasty at neonatal surgery. The degree of DIT was evaluated by the clinical symptoms, weight gain, whether reoperation was performed, and duration from the operation to receiving an oral feeding volume of at least 130 mL/kg/d. The patients then were assigned 4 grades (0 to 3). To determine the presence or absence of bowel dilation at the BP site, the plain abdominal x-rays were reviewed. RESULTS: (1) Within 2 months after surgery, 4 patients without BP underwent operation because of severe DIT. The degree of postoperative DIT in patients who had received additional BP at neonatal surgery was less than that in patients without BP (mean grade, 0.50 v. 2.08). (2) The preoperative clinical features, operative method, and postoperative weight gain were almost similar in patients with and without BP. (3) On abdominal x-ray the bowel dilation remained 6 to 12 months after the operation, but was not observed over 1 year after the operation. CONCLUSIONS: In this preliminary study, the addition of BP after tapering jejunoplasty or resection of dilated bowel may be effective in preventing early postoperative DIT. Further study is necessary to evaluate the long-term results of additional BP at neonatal surgery. J Pediatr Surg 36:1752-1756.

Anastomosis, Surgical↗

PubMed2001

Involvement of c-Jun NH2-terminal kinase-1 in heat-induced apoptotic cell death of human monoblastic leukaemia U937 cells.

PURPOSE: To determine the involvement of c-Jun NH(2)-terminal kinase-1 (JNK1) and possibly of HSP27 in heat-induced apoptosis of human monoblastic leukaemia U937 cells. MATERIALS AND METHODS: Dominant negative JNK1 (APF), in which the phosphorylation sites Thr-Pro-Tyr were changed to Ala-Pro-Phe, was overexpressed in U937 cells. Cell viability and DNA fragmentation were analysed by the erythrosin-B dye exclusion test and by agarose gel electrophoresis, respectively. Expression of activated caspase-9, phosphorylated JNK1, JNK2, p38 and HSP27 was examined by Western blotting. JNK1 kinase assay was also performed using c-Jun as a substrate. RESULTS: Loss of viability, activated cleavage form of caspase-9 and DNA fragmentation were rapid in U937 cells after 44 degrees C hyperthermia, while overexpression of dominant negative JNK1 interfered with phosphorylation or activation of JNK1 without affecting that of JNK2 or p38/SAPK, and apparently delayed or reduced cleavage and activation of caspase-9, DNA fragmentation and cell death. Heat-induced phosphorylation of HSP27, observed in parental U937 cells, was suppressed and only slightly detectable in jnk1 mutant cells. CONCLUSIONS: Prolonged phosphorylation or activation of JNK1 was considered important for heat-induced apoptosis and JNK1 may control the process possibly through phosphorylation of HSP27 and caspase-9 activation in U937 cells.

Apoptosis↗

PubMed2001

Comparison between the removal effect of mechanical, Nd:YAG, and Er:YAG laser systems in carious dentin.

OBJECTIVE: The purpose of this study was to compare the effectiveness of carious dentin removal by using an Er:YAG laser irradiation and Nd:YAG laser under a continuous water spray with that of the conventional mechanical treatment in vitro. BACKGROUND DATA: Lasers are being considered as a potential replacement of conventional mechanical systems to remove diseased and healthy dental hard tissues. METHODS: First, one half of the 10 carious lesions were treated with the round steel bur and then removed. The other half were treated with the Er:YAG laser at 200-mJ pulse energy at 2 Hz. After that, one half of another set of 10 teeth was subjected to the round steel bur in which the other half was removed using the Nd:YAG laser at 6-W output power, 20 pps, and under a continuous water spray (120 mL/min). Thermal change during each treatment and the time required for carious dentin removal was determined, and the surface characteristic was observed using the scanning electron microscopic (SEM). RESULTS: The Er:YAG or Nd:YAG laser irradiation time was almost two or three times longer than the bur treatment, respectively. From the SEM study, it was found that the lased cavity surface revealed various patterns of microirregularity, and there was also no smear layer. CONCLUSIONS: It can be suggested that under adequate water spray and with a careful irradiation technique, cavities without sign of thermal damage to the surrounding tissues as well as dental pulp could be produced with the Er:YAG and Nd:YAG laser.

Dental Caries↗

PubMed2001

Removal of carious dentin by Er:YAG laser irradiation with and without carisolv.

OBJECTIVE: The purpose of this study was to investigate the effectiveness of caries removal by using an Er:YAG laser irradiation with and without Carisolv, in vitro. BACKGROUND DATA: Effective ablation of dental hard tissues using Er:YAG laser has been reported and its application to caries removal has been expected. METHODS: Five extracted human teeth were selected for Carisolv and burr treatment. One-half of the lesion was treated with the Carisolv and then removed. The other half was removed using burr treatment. Fifty teeth were subjected to Er:YAG laser treatment with and without Carisolv. First, Carisolv was applied on one-half of each carious lesions for 1 min and followed by the Er:YAG laser irradiation at 60-140 mJ, 2 Hz for another 1 min; the other half was treated with Er:YAG laser only. The cavity was carefully assessed by DIAGNOdent. Each lesion was photographed before and after treatment, and the treated cavity was observed by microscopy and with scanning electron microscope (SEM). RESULTS: Our results revealed that application of Carisolv followed by Er:YAG laser irradiation at 100-140 mJ pulse energy effectively removed dentin caries. From the SEM study, it was found that the cavity surface treated with the laser revealed various patterns of microirregularity, often accompanied by microfissure propagation. There was also no smear layer. CONCLUSIONS: It was revealed that Er:YAG laser and Carisolv could provide an alternative technique for caries removal for conventional mechanical drilling and cutting.

Dental Caries↗

PubMed2001

Study on acid resistance of human dental enamel and dentin irradiated by semiconductor laser with Ag(NH3)2F solution.

OBJECTIVE: The purpose of this study was to investigate the acquired acid resistance of human dental enamel and dentin treated by 38% diamine silver fluoride [Ag(NH3)2F] solution and semiconductor (diode) laser irradiation in vitro. BACKGROUND DATA: There have been no reports on the acid-resistant effect by combined use of fluoride and semiconductor laser. METHODS: Sixty crowns of extracted human molars were divided into two groups for enamel and dentin samples, and each group was subdivided into three subgroups of 10 each. Each subgroup of enamel and dentin samples served as a control; one was treated with Ag(NH3)2F and the other was treated with Ag(NH3)2F and semiconductor laser irradiation at 2 W for 30 sec. Then all samples were immersed in 5 ml of 0.1 M lactic acid (pH 4.8) at 37 degrees C for 24 h. The concentration of calcium ion (Ca2+) dissolved in the solution was measured by atomic absorption spectrophotometry, and the samples were observed by stereoscopy and scanning electron microscopy (SEM). RESULTS: In both enamel and dentin samples, dissolved Ca2+ concentration in Ag(NH3)2F- or Ag(NH3)2F- and laser-treated group was significantly decreased compared with that in the control (p < 0.01). SEM findings showed that numerous cubic particles ranging from 0.1 to 0.5 mcirom were observed only in the combined treated groups of both enamel and dentin samples. CONCLUSIONS: A significantly decreased solubility of human enamel and dentin was acquired after treatment by Ag(NH3)2F and semiconductor laser irradiation, which suggested that this combined use has the capability of a more efficient acid-resistant effect on human dental hard tissues.

Cariostatic Agents↗

PubMed2001

Analysis of surface roughness of enamel and dentin after Er,Cr:YSGG laser irradiation.

OBJECTIVE: The purpose of this investigation was to compare the surface roughness of enamel and dentin following the Er,Cr:YSGG laser irradiation and acid etching. BACKGROUND DATA: Laser-roughened enamel or dentin surfaces have been expected to enhance restorative materials bond strength. MATERIALS AND METHODS: Er,Cr:YSGG laser irradiation was performed in one half of each polished enamel or dentin sample at 3 W (33.9 J/cm2, with air 70% and water 20%,) pulse energy for 6 sec. Then the other half was treated with 37% phosphoric acid for 30 sec. Surface roughness and morphological studies were performed. RESULTS: It was found that surface roughness was significantly increased with the laser system. Scanning electron microscopy analysis showed that irradiated surface produces a rough surface that was completely lacking of a smear layer; there was also no cracking of enamel or dentin. CONCLUSION: Er,Cr:YSGG laser irradiation could provide an effective and alternative method to the acid etch technique.

Acids↗

PubMed2001

Whole-cell response characteristics of ciliated and microvillous olfactory receptor neurons to amino acids, pheromone candidates and urine in rainbow trout.

Olfactory lamellae of teleosts contain two morphologically different types of olfactory receptor neurons (ORNs): ciliated ORNs (cORNs) and microvillous ORNs (mORNs). However, little is known about the functional difference between these two types of ORNs in fish olfaction. We isolated cORNs and mORNs using a Ca(2+)-free solution method from olfactory organs of the rainbow trout and examined their response characteristics to various odorants including fish pheromone candidates by whole-cell voltage-clamp techniques. Quadruple mixture of amino acids, single amino acids, steroids (analogues of DHP; 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one and ECG; etiocholan-3 alpha-ol-17-one glucuronide), prostaglandins (PGFs) and urine samples collected from immature and mature female fish were applied focally to olfactory cilia or microvilli using a multi-barreled stimulation pipette with a pressure ejection system. Inward current responses to odorants were recorded from both cORNs and mORNs at a holding potential of -60 mV. cORNs responded to the amino acid mixture, single amino acids, urine samples and ECG, whereas mORNs responded specifically either to the amino acid mixture or single amino acids. The response profiles of both cORNs and mORNs to various odorants varied widely. None of cORNs and mORNs responded to fish pheromone candidates, PGFs and DHPs. Androgen treatment of immature fish did not influence olfactory sensitivity of both cORNs and mORNs to the amino acid mixture and both urine samples. Amino acid and bile acid analyses by HPLC showed that both urine samples contained 35 amino acids (1-40 mM) and trace amounts of taurocholic acid and glycoursodeoxycholic acid. Our results suggest that cORNs are 'generalists' that respond to a wide variety of odorants, including pheromones, whereas mORNs are 'specialists', specific to amino acids, and also suggest that PGFs and DHPs are not pheromones for the rainbow trout.

Amino Acids↗

PubMed2001

A putative GDP-GTP exchange factor is required for development of the excretory cell in Caenorhabditis elegans.

The Caenorhabditis elegans excretory cell extends tubular processes, called canals, along the basolateral surface of the epidermis. Mutations in the exc-5 gene cause tubulocystic defects in this canal. Ultrastructural analysis suggests that exc-5 is required for the proper placement of cytoskeletal elements at the apical epithelial surface. exc-5 encodes a protein homologous to guanine nucleotide exchange factors and contains motif architecture similar to that of FGD1, which is responsible for faciogenital dysplasia. exc-5 interacts genetically with mig-2, which encodes Rho GTPase. These results suggest that EXC-5 controls the structural organization of the excretory canal by regulating Rho family GTPase activities.

Amino Acid Sequence↗

PubMed2001

The Saccharomyces cerevisiae small GTPase, Gsp1p/Ran, is involved in 3' processing of 7S-to-5.8S rRNA and in degradation of the excised 5'-A0 fragment of 35S pre-rRNA, both of which are carried out by the exosome.

Dis3p, a subunit of the exosome, interacts directly with Ran. To clarify the relationship between the exosome and the RanGTPase cycle, a series of temperature-sensitive Saccharomyces cerevisiae dis3 mutants were isolated and their 5.8S rRNA processing was compared with processing in strains with mutations in a S. cerevisiae Ran homologue, Gsp1p. In both dis3 and gsp1 mutants, 3' processing of 7S-to-5.8S rRNA was blocked at three identical sites in an allele-specific manner. In contrast, the 5' end of 5.8S rRNA was terminated normally in gsp1 and in dis3. Inhibition of 5.8S rRNA maturation in gsp1 was rescued by overexpression of nuclear exosome components Dis3p, Rrp4p, and Mtr4p, but not by a cytoplasmic exosome component, Ski2p. Furthermore, gsp1 and dis3 accumulated the 5'-A0 fragment of 35S pre-rRNA, which is also degraded by the exosome, and the level of 27S rRNA was reduced. Neither 5.8S rRNA intermediates nor 5'-A0 fragments were observed in mutants defective in the nucleocytoplasmic transport, indicating that Gsp1p regulates rRNA processing through Dis3p, independent of nucleocytoplasmic transport.

Active Transport, Cell Nucleus↗

PubMed2001

Serum immunosuppressive acidic protein as a potent prognostic factor for patients with metastatic renal cell carcinoma.

BACKGROUND: Estimation of survival probability of individual patients with metastatic renal cell carcinoma was difficult owing to diverse prognostic factors. We analyzed serum immunosuppressive acidic protein (IAP) levels and the cutoff value, then tested its validity for assessing patients' prognoses. METHODS: Serum IAP was measured longitudinally in 84 patients with metastatic disease. Before therapy, cutoff levels of IAP were tested every 20 microg/ml between 600 and 1200 microg/ml. The prognostic importance of IAP and its cutoff level was estimated. RESULTS: The cutoff level of IAP was set at 800 microg/ml for 40 patients who had metastatic disease with the primary tumor in situ and for 44 patients with recurrent disease. IAP was found to be a significant prognostic factor for both patient groups. CONCLUSIONS: Serum IAP is an important prognostic factor for patients with metastatic renal cell carcinoma. Stratification of patients according to prognosis is feasible using the cutoff level.

Adult↗

PubMed2001

Successful unrelated cord blood transplantation in Philadelphia chromosome positive acute lymphoblastic leukemia during pulmonary aspergillosis treated by anti-fungal therapy, granulocyte colony-stimulating factor-mobilized granulocytes and surgical resection: case report.

A 3-year-old girl with Philadelphia chromosome positive acute lymphoblastic leukemia developed pulmonary aspergillosis during severe neutropenia by re-induction therapy. She was treated by intravenous fluconazole, oral itraconazole with plasma level monitoring and surgical resection of the focus for 3 months after clinical diagnosis of fungal infection was made. Once she had recovered from surgery we attempted to induce remission with anti-fungal treatment. She developed fever and neutropenia and appeared unlikely to remit with conventional chemotherapy. Unrelated one-antigen-mismatched cord blood (CB) transplantation was performed 2 months after the induction therapy. Her pulmonary aspergillosis was reactivated during subsequent conditioning. Anti-fungal drugs were switched to amphotericin B and granulocyte colony-stimulating factor-mobilized granulocyte concentrates were transfused. She obtained engraftment and has maintained complete hematological and molecular remission without signs of aspergillus infection for 13 months so far after transplantation. Even very high-risk transplantation in pediatric patients could be successfully supported by carefully designed intense comprehensive medical care.

Amphotericin B↗

PubMed2001

Expression and exon/intron organization of two medaka fish homologs of the mammalian guanylyl cyclase A.

Two cDNA clones (OlGC2 and OlGC7) and their genomic DNA clones encoding medaka fish homologs of mammalian natriuretic peptide receptor/membrane guanylyl cyclase A (GC-A) were isolated, and their complete nucleotide sequences were determined. The open reading frame predicts a protein of 1,063 amino acids for OlGC2 cDNA (4,283 bp), and one of 1,055 amino acids for OlGC7 cDNA (3,721 bp), respectively. Northern blot analyses demonstrated 4.7 kb OlGC2 transcripts in the kidney and gill, and 4.0 kb OlGC7 transcripts in the kidney, brain, and ovary, while RNase protection analyses revealed that both genes are expressed in various adult organs. Both the OlGC2 (about 33.0 kbp) and OlGC7 (about 44.3 kbp) genes consist of 22 exons with an exon/intron organization similar to those of the human GC-A gene (about 16.6 kbp) and medaka fish GC-B homolog gene (OlGC1, about 93 kbp). Intron 4 of OlGC2 contains two repeated sequence (RS) clusters, designated as RS1 (about 1 kbp) and RS2 (about 5 kbp), consisting of nucleotide 5'-AGCCTCTGCTCCTCCTTC-3'. In addition, many identical but variably sized nucleotide sequences were found in introns in OlGC1, OlGC2, OlGC6, and OlGC7. The OlGC2 and OlGC7 genes both have no apparent TATA box in the 5' flanking region upstream of the putative transcription initiation point, but several consensus sequences for cis-regulatory elements, including C/EBP, CREB, NF-IL6, and Sp1 and AP-2, NF-IL6, c-Myb, and Sp1 are present in the 5'-flanking region of OlGC2 and OlGC7, respectively.

Amino Acid Sequence↗