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Biomedical subjects

A Watanabe

Publications and source records attributed to A Watanabe.

At least 145 records · Page 8Linked to original sources
PubMed2000

Prevention of fibrous layer formation between bone and adhesive bone cement: in vivo evaluation of bone impregnation with 4-META/MMA-TBB cement.

We have studied a new adhesive bone cement, that consists of 4-methacryloyloxyethyl trimellitate anhydride (4-META) and methylmethacrylate (MMA) as monomers, tri-n-butyl borane (TBB) as the initiator, and polymethylmethacrylate powder (4-META/MMA-TBB cement). This cement has shown remarkable adhesive properties to bone in vitro. In this study, we assessed the interface in vivo periodically. The femora of rabbits were fenestrated and filled with either the 4-META/MMA-TBB cement or a conventional polymethylmethacrylate cement. The animals were killed after 1, 4, 12, and 24 weeks to analyze the interface by optical microscopy and transmission electron microscopy. Optical microscopic examinations showed that the cured 4-META/MMA-TBB adhesive cement bonded to bone directly for 24 weeks, whereas a fibrous tissue layer was observed between the bone and cured conventional cement at 12 weeks after the operation. The transmission electron microscopy views of 4-META/MMA-TBB cement bonded to bone demonstrated a unique "hybridized bone" with the cement in the subsurface of the substrate in every case. The formation of the hybridized bone indicates the bonding mechanism of the adhesive cement to bone, which prevents the fibrosis intervention between bone and cement. These results suggest that the biomechanical and adhesive properties of 4-META/MMA-TBB cement make it a useful bone-bonding agent in orthopedic surgery.

Animals↗
PubMed2000

Thrombotic thrombocytopenia purpura caused by piperacillin successfully treated with plasma infusion.

An 81-year-old man was admitted to the hospital with a fever and loss of appetite. After treatment with piperacillin sodium (PIPC), the patient exhibited thrombocytopenia, hemorrhagic colitis, and drug-induced skin eruption. On the fifth day after PIPC induction, he further experienced neurological abnormalities, such as disorientation and confusion, renal dysfunction, and microangiopathic hemolytic anemia (MAHA). The patient was diagnosed with thrombotic thrombocytopenic purpura (TTP) on the basis of thrombocytopenia, MAHA, renal dysfunction, fever, and neurological abnormalities. Infusion of fresh-frozen plasma was initiated for treatment. His condition improved markedly after this treatment. It is rare for TTP to be accompanied with hemorrhagic colitis and skin eruption. These symptoms were induced by PIPC and were successfully treated with plasma infusion.

Aged↗
PubMed2000

Molecular cloning and DNA analysis of the orotidine-5'-phosphate decarboxylase gene from the yeast Saccharomyces exiguus Yp74L-3.

The orotidine-5'-phosphate decarboxylase gene of Saccharomyces exiguus Yp74L-3 was cloned as a DNA fragment complementing a ura4 mutation of this yeast. The coding region of the gene is 807 bp in length, and represents 68.7% similarity to the corresponding gene of S. cerevisiae (URA3). The cloned URA4 gene was shown to be located on the 790-kbp Chromosome (chr) VIII of S. exiguus Yp74L-3. The neighbor-joining phylogenetic tree based on the orotidine-5'-phosphate decarboxylase coding sequences indicates that S. exiguus Yp74L-3 is closely related to Kluyveromyces yeasts, as well as to a S. cerevisiae laboratory strain.

Chromosome Mapping↗
PubMed2000

Rapid growth of a retroperitoneal rhabdomyosarcoma following right hemicolectomy for ascending colon cancer: report of a case.

We report herein the case of a 69-year-old man in whom rapid growth of a retroperitoneal rhabdomyosarcoma occurred following hemicolectomy for ascending colon cancer. On his first admission for surgery, a small lesion, 1.5 cm in diameter, was detected adjacent to the inner side of the left kidney by abdominal axial computed tomography (CT), which was initially suspected to be a benign lesion; however, a postoperative follow-up CT scan done 5 months later revealed that the lesion had enlarged remarkably to 8 cm in diameter. Thus, total resection was performed under the presumed diagnosis of a malignant retroperitoneal tumor. The tumor was found to be adjacent to the inner portion of the left kidney and covered by Gerota's fascia. As it involved the ileolumbar muscle and had a metastatic lymph node, complete resection was performed. The resected specimen was 8.5 x 6.5 x 5 cm in size and was histologically confirmed as a retroperitoneal rhabdomyosarcoma of embryonal type. Two courses of adjuvant chemotherapy with adriamycin, vincristine, and cyclophosphamide were given, and the patient has shown no signs of recurrence for 2 years since his second operation.

Adenocarcinoma↗
PubMed2000

Changes in the expression of lipid-mediated signal-transducing enzymes in the rat liver after partial hepatectomy.

Prostaglandins (PGs), metabolites of arachidonic acid, and other lipid mediators produced by phospholipases C (PLC) and D (PLD) are thought to play important roles in hepatocyte proliferation. The present study examined lipid-mediated signaling in the rat liver after partial hepatectomy (PH). Rats were killed 1-48 h after 70% PH and the remaining liver tissue was removed. The mRNA and protein levels of some signaling molecules were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting, respectively. The levels of hepatocyte growth factor (HGF) mRNA showed a biphasic change, peaking 3 h and 9 h after PH. The expression of PLCdelta4 peaked at 12 h, but no significant changes in the expression of PLCbeta1 and PLCgamma1 were seen after PH. T he enzymes involved in PG production, namely, the expression of cytosolic PLA2 and cyclooxygenase 1 (COX1), remained constant after PH. However, the mRNA of COX2 increased transiently at 3 h, and Western blot analysis showed an increase in COX2 protein at 12 h. The expression of PLD1b peaked at 9 h and PLD1a at 12 h, whereas the expression of PLD2 remained consistent for 24 h. These results suggest that transcriptional controls may act for PLCdelta4, PLD1a/b, and COX2 during hepatocyte regeneration after PH.

Animals↗
PubMed2000

Adenosquamous carcinoma of the remnant stomach: report of a case.

We report herein the case of a 59-year-old man found to have adenosquamous carcinoma of the remnant stomach which demonstrated rapid progression. The patient was admitted to our hospital to undergo surgery for a papillary tumor of the remnant stomach. Total resection of the remnant stomach with lymph node dissection was performed, and pathological examination confirmed a diagnosis of adenosquamous carcinoma with invasion into the muscularis propria and lymph node metastasis around the perigastric areas. Multiple liver metastases were found 6 months after the operation, for which a right hepatectomy was performed with curative intent; however, he died 2 months later due to lymphangitis carcinomatosa of the lung.

Carcinoma, Adenosquamous↗
PubMed2000

Significance of egg-jelly substances in the internal fertilization of the newt, Cynops pyrrhogaster.

Japanese newt, Cynops pyrrhogaster, undergoes internal fertilization as do most urodeles. In this study, we focused on the roles of egg-jelly in fertilization of C. pyrrhogaster and characterized the substances associated with those roles. When dry sperm were directly inseminated onto the egg, normal fertilization occurred without the presence of water. Egg-jelly extract (JE) prepared with Steinberg's salt solution contained the activity for the initiation of sperm motility. A substance of about 50 kDa in JE was significant for this activity; an inactive form of the substance probably exists in JE. Strong activity to induce acrosome reaction was detected in JE. It was inhibited by the treatment of JE with WGA, suggesting that carbohydrate in JE may be important for the induction of the acrosome reaction. This study suggests that two significant processes of fertilization are regulated by substances in the egg-jelly of the newt, C. pyrrhogaster.

Acrosome Reaction↗
PubMed2000

Interferon-gamma increases IL-12 mRNA expression and attentuates allergic late-onset airway responses in the Brown Norway rat.

Interferon gamma is a T-helper cell (Th)-1-type cytokine that has been suggested to inhibit the development of an atopic Th2-type profile of cytokine expression. The aim of this study was to investigated the effect of exogenous rat interferon gamma on antigen-induced airway responses, and on Th1 and Th2-type cytokine messenger ribonucleic acid (mRNA) expression in the Brown Norway rat. Rats were actively sensitized to ovalbumin and 14 days later underwent an aerosolized ovalbumin challenge. Animals were intratracheally administered either interferon gamma (3,000 U) or control solvent 30 min prior to, and 2 and 4 h following, antigen challenge. Lung resistance was monitored over an 8-h time period. Using in situ hybridization and immunocytochemistry, the levels of Th1- (interleukin-12) and Th2-type (interleukin4 and -5) cytokine mRNA, and major basic protein expression in the bronchoalveolar lavage fluid of these rats 8 h after ovalbumin challenge were also determined. Administration of interferon gamma attenuated the development of the late-onset airways response in ovalbumin-sensitized antigen-challenged rats (p<0,05). The expression of interleukin-4 and -5 mRNA in the bronchoalveolar lavage fluid of interferon gamma treated rats was significantly attenuated compared to ovalbumin-challenged saline-treated controls (p<0.001). This was accompanied by a significant increase in the expression of interleukin-12 mRNA, and a reduction in eosinophil numbers. Intratracheal administration of interferon gamma modulates the allergic late-onset airways response in rats, and this is associated with a reduction in the expression of T-helper cell 2-type cytokines and an increase in interleukin-12 messenger ribonucleic acid expression within the airways. The present results support a role for interferon gamma in the pathophysiology of acute allergic airway responses, possibly by virtue of its ability to modulate T-helper cell 1- 2-type cytokine expression within the lungs.

Airway Resistance↗
PubMed2000

Allogeneic hematopoietic transplantation of CD34+ selected cells from an HLA haplo-identical related donor. A long-term follow-up of 135 patients and a comparison of stem cell source between the bone marrow and the peripheral blood.

We studied the outcome of allogeneic transplants in 135 patients who received selected BM and/or PBSC CD34+ cells from HLA haplo-identical related donors. Donor engraftment was achieved in 108 of 128 evaluable transplants. Engraftment failure occurred more often in non-malignant than in malignant diseases (10 of 25 vs 17 of 103, P = 0.010). The CD34+ cell dose was associated with the speed of neutrophil and platelet recovery, but the cell source was not. Acute GVHD (> or = grade II) developed in 21.0 +/- 3.7%. Chronic GVHD occurred more frequently in malignancies than in non-malignancies (44.1 +/- 7.6% vs 0.0%, P = 0.0075), and more in PBSC recipients than in BM recipients (53.6 +/- 9.4% vs 17.4 +/- 9.3%, P = 0.0054). Relapse rate was higher in high risk patients than in standard risk patients (78.7 +/- 7.1% vs 22.1 +/- 10.0%, P = 0.0001). Probabilities of disease-free survival (DFS) were 14.2 +/- 3.5% in malignancies and 25.7 +/- 9.2% in non-malignancies. Probabilities of DFS in standard and high risk patients were 39.4 +/- 9.2% and 5.7 +/- 2.8% (P = 0.0001). A high incidence of graft failure, infection and relapse was observed and resulted in high mortality.

Actuarial Analysis↗
PubMed2000

Identification of a polymorphism in the promoter region of DRD4 associated with the human novelty seeking personality trait.

Polymorphism in the human dopamine D4 receptor gene (DRD4) exon III has been associated in some but not all studies of the human personality trait of Novelty Seeking. We searched for polymorphisms in the 5' region of DRD4 and identified six polymorphisms as follows: -1217G Ins/Del, -809G/A, -616C/G, -603T Ins/Del, -602(G)8-9, and -521C/T. Associations between these polymorphisms and personality traits measured by the Temperament and Character Inventory (TCI) were investigated in 86 healthy Japanese volunteers. The -521C/T polymorphism was significantly associated with Novelty Seeking (P = 0.0001). Subjects with the C/C genotype exhibited the highest Novelty Seeking scores and those with the T/T genotype exhibited the lowest. A transient expression method revealed that the T variant of the C-521T polymorphism reduces transcriptional efficiency. The present study suggests a contribution of dopamine D4 receptor availability to individual differences in Novelty Seeking behavior. Molecular Psychiatry (2000) 5, 64-69.

Adolescent↗
PubMed2000

Association study on the DUSP6 gene, an affective disorder candidate gene on 12q23, performed by using fluorescence resonance energy transfer-based melting curve analysis on the LightCycler.

We introduced a new genotyping method, fluorescence resonance energy transfer-based melting curve analysis on the LightCycler, for the analysis of the gene, DUSP6 (dual specificity MAP kinase phosphatase 6), in affective disorder patients. The DUSP6 gene is located on chromosome 12q22-23, which overlaps one of the reported bipolar disorder susceptibility loci. Because of its role in intracellular signalling pathways, the gene may be involved in the pathogenesis of affective disorders not only on the basis of its position but also of its function. We performed association analysis using a T>G polymorphism that gives rise to a missense mutation (Leu114Val). No evidence for a significant disease-causing effect was found in Japanese unipolars (n = 132) and bipolars (n = 122), when compared with controls (n = 299). More importantly, this study demonstrates that melting curve analysis on the LightCycler is an accurate, rapid and robust method for discriminating genotypes from biallelic markers. This strategy has the potential for use in high throughput scanning for and genotyping of single nucleotide polymorphisms (SNPs). Molecular Psychiatry (2000) 5, 489-494.

Journal Article↗
PubMed2000

Restricted usage of T-cell receptor alpha-chain variable region (TCRAV) and T-cell receptor beta-chain variable region (TCRBV) repertoires after human allogeneic haematopoietic transplantation.

We analysed T-cell receptor alpha-chain variable region (TCRAV) and T-cell receptor beta-chain variable region (TCRBV) repertoires in peripheral blood mononuclear cells (PBMCs) from 34 recipients of allogeneic bone marrow transplantation (allo-BMT), seven of allogeneic peripheral blood stem cell transplantation and 19 of autologous peripheral blood stem cell transplantation using the quantitative microplate hybridization assay. TCR usage skewed at an early period (6-7 weeks) after BMT. The change was more apparent in allogeneic recipients than in autologous recipients. In particular, a predominant increase was detected in the frequency of VA1-4 (26%, 11 of 41 recipients), VA3-1 (32%) and VB24-1 (28%). Interestingly, acidic amino acid residues frequently followed the arginine residue in complementarity-determining region 3 of BV24S1. We further examined the extent of skew using samples obtained at serial time points after transplantation. The normalization of skewed repertoires occurred over a long period of time (> 8 years). There was a significant difference in the rate of normalization of skewed TCR repertoires between adult and child recipients (P < 0.05). The results suggest that these T cells may have expanded in response to allogeneic antigens, such as miHA (minor histocompatibility antigen), and that altered repertoires are eventually normalized by T-cell regeneration via a thymic-dependent pathway in children.

Adolescent↗
PubMed2000

Effect of intramammary infusion of tumour necrosis factor-alpha on milk protein composition and induction of acute-phase protein in the lactating cow.

The present study was designed to evaluate the effects of tumour necrosis factor-alpha (TNF-alpha) on lactating bovine mammary functions such as milk protein secretion and the integrity of the milk-blood barrier. The effect on the induction of the systemic inflammatory response was also examined using concentrations of serum haptoglobin (Hp), a major inflammatory acute-phase protein, as an index. One hundred micrograms per mammary gland of recombinant bovine (rBo) TNF-alpha or placebo saline was individually infused into a rear mammary gland of each of four lactating cows, and milk and blood samples were collected before and 4, 8, 24, 32, 48, 96 and 168 h after infusion. In the rBoTNF-alpha-infused gland, increases of somatic cell counts were observed at 4-48 h. Although concentrations of total milk protein were not changed, compositions of milk proteins varied following rBoTNF-alpha infusion. Concentrations of caseins, alpha-lactalbumin and beta-lactoglobulin were significantly decreased at 4 and 8 h. Lactoferrin concentrations were significantly increased at 4 h. Significant infiltrations of serum albumin, immunoglobulin G1 (IgG1) and IgG2 were observed at 4 and 8 h. Elevations of the serum concentration of Hp were detected at 8-32 h, but were very small in comparison with those reported in inflammatory diseases. Changes in rectal temperature and white blood cell counts were not significant. These results show that single rBoTNF-alpha infusion into the lactating mammary gland suppresses the lactogenic function of the gland and influences the function of the milk-blood barrier, with little effect on the generalized inflammatory response.

Acute-Phase Proteins↗
PubMed2000

Effect of branched-chain amino acids on the composition and cytolytic activity of liver-associated lymphocytes in rats.

BACKGROUND: Although branched-chain aminoacids (BCAA) are reported to be effective in prolongation of the mean survival time of patients with liver cirrhosis, it is not clear whether BCAA could influence the immune function in those patients. METHODS: Branched-chain amino acids were given as a supplement to carbon tetrachloride-induced cirrhotic rats, and an aminogram of the liver and kinetics of liver-associated lymphocytes (LAL) were then analysed. RESULTS: Liver cirrhosis was established at the 12th week, and glutathione S-transferase placental form (GST-P)-positive lesions, which are known to be pre-neoplastic lesions, occupied 1.72+/-0.84% of the liver at the 16th week in the controls. At this time the LAL showed an increase in the number of CD5-, CD8- and CD18-positive cells and augmentation of lectin-dependent cellular cytotoxicity (LDCC) activity. Furthermore, supplementation of BCAA increased the number of LAL, especially CD8-positive cells and natural killer cells, and augmented LDCC activity of LAL at the 16th week. The number of LAL was positively correlated with the valine concentration in the plasma and liver, and the area of GST-P-positive lesions tended to be decreased in the BCAA group. CONCLUSION: These findings suggest that BCAA administration has stimulatory effects on the local immune systems of the liver, which may have a potential to inhibit hepatocarcinogenesis. Moreover, among all amino acids valine might be an important amino acid for enhancing the immune function of LAL.

Amino Acids, Branched-Chain↗
PubMed2000

Portal-systemic encephalopathy in non-cirrhotic patients: classification of clinical types, diagnosis and treatment.

Hepatic encephalopathy is suspected in non-cirrhotic cases of encephalopathy because the symptoms are accompanied by hyperammonaemia. However, the cause of the large portal-systemic shunt formation observed in these cases is not clear, as cirrhosis and portal hypertension are absent. The frequency of such cases reported in the literature is increasing with progress and spread of abdominal imaging diagnostic techniques. Some cases have been misdiagnosed as psychiatric diseases (dementia, depression and others) and consequently patients have been hospitalized in psychiatric institutions or geriatric facilities. Some paediatric cases have also been misdiagnosed. Therefore, the importance of accurate diagnosis of this disease should be strongly emphasized. Some paediatric cases have also been misdiagnosed. When psychoneurological symptoms are suggestive of hepatic encephalopathy but objective and subjective symptoms or abnormal values of liver function tests are not sufficiently indicative of liver cirrhosis, portal-systemic encephalopathy should be suspected. Abnormal angiograms of the portal vein, superior mesenteric vein or splenic vein are conclusive evidence of portal-systemic encephalopathy. Transrectal portal scintigraphy also provides information useful for detection of shunts and a quantitative estimation of shunt index. We classified the disease into five types based on whether the shunt is formed inside or outside the liver. Type I (intrahepatic type) designates cases in which shunts are located between the portal and systemic veins. Type II designates a type of intra/extrahepatic shunt that originates from the umbilical part of the portal vein and serpentines in the liver, then leaves the liver. Type III (extrahepatic type) occurs most frequently. Type IV (extrahepatic) is accompanied by shunts similar to those in type III, but hepatic pathology presents as idiopathic portal hypertension. Type V (extrahepatic) represents the congenital absence of the portal vein, where the superior mesenteric vein joins the intrahepatic inferior vena cava or the left renal vein. The prevalence of each type in our country was examined by a nationwide investigation. In addition to the conventional diet or drug treatments, obliteration by less invasive interventional radiology using a metallic coil and ethanol has recently been used more frequently than surgical occlusion of shunts. Shunt-preserving disconnection of portal and systemic circulation and partial splenic artery embolization are also performed. International investigation of the disease status and establishment of diagnostic and therapeutic methods for the disease are awaited and investigation of long-term prognosis after therapy is also necessary.

Diagnosis, Differential↗
PubMed2000

Experience with 24 cases of reconstructive anterior skull base surgery: classification and evaluation of postoperative facial appearance.

This article details our experience with 24 cases of anterior skull base reconstruction after tumor resection. They were classified into four types according to the resected region. In 11 cases of type I resection, the orbital part of frontal bone and/or cribriform plate of ethmoid bone were resected. In two cases of type II resection, the orbital contents and partial orbital bone were resected with the addition of type I. In five cases of type III resection, the maxillary bone was resected with the addition of type II. In six cases of type IV resection, the zygomatic bone and/or facial skin were resected with the addition of type III. The tumor originating from intracranial region was 25% of this series and all of them belonged to type I. The tumor originating from extracranial region tumor was 75% and its resected region was more extensive. In type I and II resections, the cranial flap, radial forearm free flap, or a combination of the two was used for reconstruction. The rectus abdominis myocutaneous/muscle free flap was used for reconstruction of massive defects in type III and IV defects. Total incidence of postoperative complications was 16.7%. Donor site deformity of the cranial flap at the frontal and temporal region in types I and II resections and facial contour deformity in zygomatic region and defect of upper and/or lower palpebra in type IV resection were major problems with postoperative facial appearance. Although use of the rectus abdominis myocutaneous free flap combined with costal cartilages improved the midfacial contour, palpebral reconstruction remained an unsolved problem in reconstructive skull base surgery. The reconstructive goals in skull base surgery are not only to obtain safe and reliable skull base reconstruction but also to restore the facial appearance postoperatively.

Journal Article↗