Biomedical subjects

Hiroshi Uchida

Publications and source records attributed to Hiroshi Uchida.

15 recordsLinked to original sources

PubMed2003

Ccd1, a novel protein with a DIX domain, is a positive regulator in the Wnt signaling during zebrafish neural patterning.

Wnt signaling plays a crucial role in directing cell differentiation, polarity, and growth. In the canonical pathway, Wnt receptors activate Dishevelled (Dvl), which then blocks the degradation of a key signal transducer, beta-catenin, leading to the nuclear accumulation of beta-catenin and induction of Wnt target genes through TCF/LEF family transcription factors. Here we identified a novel zebrafish gene encoding Ccd1, which possesses a DIX (Dishevelled-Axin) domain. DIX domains are essential for the signal transduction of two major Wnt downstream mediators, Dvl and Axin. Ccd1 formed homomeric and heteromeric complexes with Dvl and Axin and activated TCF-dependent transcription in vitro. In addition, overexpression of ccd1 in zebrafish embryos led to a reduction in the size of the eyes and forebrain (posteriorization), as seen with wnt8 overexpression, whereas a dominant-negative ccd1 (DN-ccd1) caused the opposite phenotype. Furthermore, the Wnt activation phenotype induced by ccd1 was inhibited by the expression of axin1 or DN-ccd1, and the wnt8 overexpression phenotype was rescued by DN-ccd1, suggesting that Ccd1 functions downstream of the Wnt receptor and upstream of Axin. These results indicate that Ccd1 is a novel positive regulator in this Wnt signaling pathway during zebrafish neural patterning.

Amino Acid Sequence↗

PubMed2003

Quick and reversible inhibition of soybean root nodule growth by nitrate involves a decrease in sucrose supply to nodules.

The upper part of a nodulated soybean root hydroponically cultured in a glass bottle was monitored using a computer microscope under controlled environmental conditions, and the diameter of individual nodules was measured from 10-24 d after planting. The diameter of a root nodule attached to the primary root increased from 1 mm to 6 mm for 2 weeks under nitrogen-free conditions. The increase in diameter of the nodules was almost completely stopped after 1 d of supplying 5 mM nitrate, and was due to the cessation of nodule cell expansion. However, nodule growth quickly returned to the normal growth rate following withdrawal of nitrate from the solution. The reversible depression of nodule growth by nitrate was similar to the restriction of photoassimilate supply by continuous dark treatment for 2 d followed by normal light/dark conditions. In addition, the inhibitory effect of nitrate was partially alleviated by the addition of 3% (w/v) sucrose to the medium. Plant leaves were exposed to (11)C or (14)C-labelled carbon dioxide to investigate the effects of 5 mM nitrate on the translocation and distribution of photosynthates to nodules and roots. Supplying 5 mM nitrate stimulated the translocation rate and the distribution of labelled C in nitrate-fed parts of the roots. However, the (14)C partitioning to nodules decreased from 9% to 4% of total (14)C under conditions of 5 mM nitrate supply. These results indicate that the decrease in photoassimilate supply to nodules may be involved in the quick and reversible nitrate inhibition of soybean nodule growth.

Biological Transport↗

PubMed2003

[General anesthesia for disabled patients undergoing dental treatment in a general hospital].

BACKGROUND: General anesthesia for dental treatment in disabled patients may present particular problems, especially when it is done in a general hospital, compared with specialized dental hospitals. METHODS: We surveyed 24 patients who underwent dental treatment under general anesthesia in our institution during the last decade. RESULTS: Electrocardiography or chest x-ray photography was not obtained in 8 patients owing to lack of patients' cooperation. Slow induction with sevoflurane was selected in 5 patients, because intravenous cannulae could not be placed owing to their rejection. Nasotracheal intubation was performed in all patients, but no difficulty in intubation was documented. As postoperative complications, we observed convulsion in one patient and muscle rigidity in another, but no critical troubles related to circulatory or respiratory status. In patients who were treated for more than ten teeth, we observed differences in age, body weight, duration of anesthesia, maximum concentration of sevoflurane administered during anesthesia, and use of postoperative analgesics compared with the other patients. CONCLUSIONS: We found particular problems of anesthesia for disable patients undergoing dental treatment in a general hospital, and suggest that information on numbers of teeth to be treated is helpful.

Adolescent↗

PubMed2002

Profiles of connectin (titin) in atrophied soleus muscle induced by unloading of rats.

Responses of the properties of connectin molecules in the slow-twitch soleus (Sol) and fast-twitch extensor digitorum longus muscles of rats to 3 days of unloading with or without 3-day reloading were investigated. The wet weight (relative to body wt) of Sol, not of extensor digitorum longus, in the unloaded group was significantly less than in the age-matched control (P < 0.05). Immunoelectron microscopic analyses showed that a monoclonal antibody against connectin (SM1) bound to the I-band region close to the edge of the A band at resting length and moved reversibly away from the Z line as the muscle fibers were stretched. In Sol, the displacement of the SM1-bound dense spots in response to stretching decreased after hindlimb suspension. There were no changes in the molecular weights and the percent distributions of alpha- and beta-connectin in both muscles after hindlimb suspension. A significant increment of percent beta-connectin in Sol was observed after 3 days of reloading after hindlimb suspension (P < 0.05). It is suggested that the elasticity of connectin filaments in the I-band region of the atrophied Sol fibers was reduced relative to that of the control fibers. The lack of the elasticity in atrophied muscle fibers may cause a decrease in contractile function.

Animals↗

PubMed2002

Different pattern of loss of heterozygosity among endocervical-type adenocarcinoma, endometrioid-type adenocarcinoma and adenoma malignum of the uterine cervix.

It is unclear which chromosome arms frequently show loss of heterozygosity (LOH) in adenocarcinoma of the uterine cervix. To identify such chromosomal arms, LOH on 52 different chromosome loci was examined using laser capture microdissection and PCR-LOH analysis in 25 common-type adenocarcinomas, comprising 13 cases of endocervical type, 12 cases of endometrioid type and 7 cases of adenoma malignum without the component of conventional endocervical-type adenocarcinoma (designated as "pure" form). In adenocarcinomas of endocervical type and endometrioid type, LOH was commonly detected on chromosome arms 17p (62% and 50%, respectively), 1p (33% and 67%) and 22q (40% and 33%). In addition, endocervical-type adenocarcinoma frequently (> or = 30%) showed LOH on 18p (71%), 19q (50%), 19p (38%) and 16q (38%), whereas endometrioid-type adenocarcinoma frequently showed LOH on 10q (43%) and 5q (40%). LOH was only sporadically detected on 9q, 18q, or 21q in 3 of 7 cases of "pure" adenoma malignum. In a case of coexistence of "pure" adenoma malignum and adenocarcinoma in situ (AIS), LOH on 1q, 5p, 11p, 17p, 18p and 18q was detected only in AIS. LOH was accumulated on a number of chromosome arms in the adenocarcinoma at the early developmental stage before stromal invasion. Chromosomal arms that are prone to show LOH appeared to differ between the 2 types of cervical adenocarcinoma. We could suggest that "pure" adenoma malignum is of clonal and neoplastic nature in view of the detection of LOH.

Adenocarcinoma↗

PubMed2002

Bacterial fimbriae activate human peripheral blood monocytes utilizing TLR2, CD14 and CD11a/CD18 as cellular receptors.

Bacterial fimbriae are associated with a specific adherence factor, adhesin, in their microbial etiology. Porphyromonas gingivalis, as an anaerobic Gram-negative periodontopathogenic organism, is known to possess fimbriae on its cell surfaces. In this study, we demonstrated that P. gingivalis fimbriae and an active synthetic peptide composed of residues 69 - 73 of thefimbrial subunit protein, ALTTE, induced IL-6 mRNA expression and cytokine production, p38 mitogen-activated protein (MAP) kinase phosphorylation, and NF-kappaB activation in human peripheral blood monocytes. P. gingivalis fimbriae and ALTTE also induced IL-6 production via human Toll-like receptor (TLR) 2, CD14, and CD11a/CD18 (LFA-1) molecules on human monocytes. These results suggest that P. gingivalis fimbriae and these degraded peptides may play an important role in the inflamed gingival and periodontal tissues seen in the development and progression of periodontal diseases.

Adhesins, Bacterial↗

PubMed2002

Identification of a novel nonlysosomal sulphatase expressed in the floor plate, choroid plexus and cartilage.

BACKGROUND: Sulphated glycosaminoglycans (GAGs) attached to proteoglycan core proteins are implicated in cell adhesion, motility and morphogenesis. Variable sulphation patterns, which are thought to be important for regulating proteoglycan function, are generated by sequential reactions during GAG biosynthesis. However, the mechanism by which such diversity is generated remains unclear. RESULTS: A novel sulphatase, designated RsulfFP1, was isolated from rat embryos by screening for floor plate specific genes. RsulfFP1 and its orthologues show homology with other sulphatases, and have a distinctive hydrophilic insertion. In situ hybridization showed that RsulfFP1 mRNA is strongly expressed in the floor plate, choroid plexus and cartilage in rat embryos. In vitro transfection experiments revealed that the RsulfFP1 protein is localized to the Golgi apparatus and endoplasmic reticulum, and is not present in the lysosomes. It also appears to be localized on the cell surface. CONCLUSIONS: RsulfFP1, a phylogenetically conserved sulphatase, forms a novel subgroup in the sulphatase family. It shows homology with the lysosomal sulphatases involved in GAG degradation. Localization of the RsulfFP1 protein in the Golgi apparatus and on the cell surface, however, suggests that it may play a role in regulating proteoglycan-mediated signalling by the desulphation of GAGs during biosynthesis or after GAGs are presented in the extracellular space.

Amino Acid Sequence↗

PubMed2002

Expression and subcellular distribution of the active form of c-Src tyrosine kinase in differentiating human endometrial stromal cells.

Decidual growth factors and locally produced cytokines are thought to activate specific phosphorylation signalling pathway(s), thereby eliciting a variety of decidual functions. We have previously reported the activation of c-Src tyrosine kinase during ovarian steroid-induced decidualization of cultured human endometrial stromal cells. As chicken c-Src is known to be activated upon dephosphorylation of tyrosine 527 (Y527, corresponding to Y530 in human), we here employed a monoclonal antibody, clone 28, directed against the active form of human c-Src whose Y530 is dephosphorylated, and investigated whether c-Src became dephosphorylated at Y530 and thereby activated during decidualization. We found that the active form of c-Src was up-regulated and demonstrated increased kinase activity during in-vitro decidualization. Immunohistochemistry revealed that decidual cells in early pregnancy decidua were intensely stained with clone 28 when compared with the stromal cells in the non-pregnant endometrium. Moreover, the active form of c-Src translocated from a perinuclear region to the cytoplasm upon decidualization. Thus, the Y530 dephosphorylation, kinase activation, and subcellular translocation of c-Src may be intracellular signalling events associated with decidualization in vivo as well as in vitro.

CSK Tyrosine-Protein Kinase↗

PubMed2002

[Suddenly developing low output syndrome during acute thoracic aortic dissection surgery in a patient with progressive systemic sclerosis].

A 70-year-old man with progressive systemic sclerosis (PSS) suddenly developed low output syndrome (LOS) after weaning from cardiopulmonary bypass during acute thoracic aortic dissection and died in an early postoperative stage because of multiple organ failure. PSS was kept in a relatively good condition before onset of his surgical disease, but his Raynaud's phenomenon was much worse and inflammation findings were very severe before his operation. We suspected that PSS might have been involved in LOS in this case. PSS has many cardiac complications, for example spasm or organic changes of coronary artery, cardiac fibrosis, arrhythmia, secondary cardiac failure of pulmonary hypertension, pericardial inflammation, and so on, but we speculate that LOS might be caused by peripheral vessel disturbance. LOS occurs easily in chronic hypovolemic states and abnormal response of peripheral vessels due to PSS. We advise more careful anesthetic and circulatory management especially in invasive operation in PSS patients.

Acute Disease↗

PubMed2002

[Surgical stress in perioperative period of combined off-pump coronary artery bypass grafting and abdominal aortic aneurysm repair].

OBJECTIVES: It is still controversial whether we should choose simultaneous operation or two-staged operation for patients who need both coronary artery bypass grafting (CABG) and abdominal aortic aneurysm (AAA) repair. Some reports suggest that combined CABG without cardiopulmonary bypass and AAA repair is less invasive than those with cardiopulmonary bypass. We estimated surgical stress of combined off pump CABG and AAA repair (CABG + AAA) in perioperative period compared with simple AAA repair retrospectively. METHODS: Seven patients (mean 60 years) underwent simultaneous operation of off pump CABG and AAA repair in our institution. We gathered data associated with circulatory, respiratory, renal function, recovery, and so on. We also examined postoperative complication and mortality. RESULTS: All parameters, except operation time and amount of catecholamine used, were not significantly different between the two groups. There were no operative mortality and only a slight morbidity in CABG + AAA. CONCLUSIONS: Our findings suggest that careful circulatory management with adequate transfusion and catecholamine use under precise monitoring is necessary during operation, but recovery after surgery, complication, and mortality in this combined operation are almost equivalent to those of simple AAA repair. We suggest that combined operation of CABG and AAA repair can be performed effectively.

Aged↗

PubMed2002

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). I. Susceptibility distribution].

The bacterial strains isolated from patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between the period of August 2000 and July 2001. Then, the susceptibilities of them to many kinds of antimicrobial agents were investigated. The number of them were 511 strains. The breakdown of these strains was Gram-positive bacteria as 29.0% and Gram-negative bacteria as 71.0%. Susceptibilities of these bacteria to antimicrobial agents were as follows; vancomycin (VCM), ampicillin (ABPC) and imipenem (IPM) showed strong activities against Enterococcus faecalis. No increase in low-susceptible strains of E. faecalis observed against these antimicrobial agents. VCM showed a strong activity against MRSA preventing growth of all strains with 1 microgram/ml. In addition, the activity of arbekacin (ABK) was strong with the MIC90 of 2 micrograms/ml against MRSA and prevented growth of all strains with 4 micrograms/ml. ABK showed a strong activity against Staphylococcus epidermidis preventing growth of all strains with 0.5 microgram/ml. ABPC, cefotiam (CTM) and cefozopran (CZOP) also showed a relatively strong activity against S. epidermidis (MIC90: 4 to 8 micrograms/ml). Against Escherichia coli, carbapenems showed high activities: meropenem (MEPM) prevented growth of all strains within 0.125 microgram/ml; IPM prevented growth of all strains with 0.25 microgram/ml. CZOP and CTM also showed strong activities against E. coli: MIC90 of CZOP was within 0.125 microgram/ml; MIC80 and MIC90 of CTM were 0.25 and 0.5 microgram/ml, respectively. Quinolone resistant E. coli was detected at frequency of 14.0%, which was significantly higher than that in the last year. Almost all drugs showed strong activities against Klebsiella pneumoniae and Proteus mirabilis, and MEPM prevented growth of all strains within 0.125 microgram/ml. Against Pseudomonas aeruginosa, almost drugs were not so active. The MIC90 of carbapenems and gentamicin (GM) were 16 micrograms/ml and those of all other drugs were more than 32 micrograms/ml. Against Serratia marcescens, the MIC90 of IPM and GM were the lowest value being 2 micrograms/ml, and that of MEPM was 4 micrograms/ml.

4-Quinolones↗

PubMed2002

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). II. Background of patients].

Five-hundred eighty eight bacterial strains isolated from 435 patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between August 2000 and July 2001. Then, the clinical background of patients were investigated such as sex, age, and type of infections, infections and kind of bacteria, frequency of bacteria isolation by age and infections, bacteria and infections by timing of antibiotics administration, and bacteria and infections by surgical procedures. About the relationship between age and sex of patients and type of infections, the number of male patients aged less than 50 years was few, and complicated UTIs without indwelling catheter was the most frequent. In females, the number of patients aged less than 20 years was few. The majority of female patients aged 40 years and over had complicated UTIs while uncomplicated UTIs was most frequent in the patients being twenties. As for type of infections and kind of bacteria, Escherichia coli decreased when the infections became complicated, and pseudomonas aeruginosa increased when the infection became complicated. Enterococcus faecalis was isolated more frequently in complicated UTIs than in uncomplicated UTIs. Considering this result by age of patients, isolated frequency of E. coli was gradually decreased with aging in patients aged 20 years and over with uncomplicated UTIs or complicated UTIs without indwelling catheter. The isolated frequencies of Klebsiella spp., P. aeruginosa, and E. faecalis were high in the patients with complicated UTIs without indwelling catheter. In the patients aged 70 years and over with complicated UTIs with indwelling catheter, P. aeruginosa and E. faecalis were frequently isolated. As for type of causative organisms in UTIs before and after the administration of antibiotics, the isolation of bacteria was remarkably decreased after administration in the patients with uncomplicated UTIs and complicated UTIs without indwelling catheter. E. coli decreased after administration of antibiotics, and P. aeruginosa increased after administration in the patients with all types of infections. As for type of causative organisms in UTIs and surgical procedures, E. coli was frequently isolated in the patients without surgery in all types of infections, while P. aeruginosa was frequently isolated in the patients who underwent surgery. In uncomplicated UTIs, Proteus spp. and E. faecalis were frequently isolated in the patients with surgery. In complicated UTIs without indwelling catheter, Klebsiella spp. was frequently isolated in the patients without surgery and E. faecalis was frequently isolated in the patients with surgery. In complicated UTIs with indwelling catheter, most of organisms except P. aeruginosa and S. aureus were frequently isolated in the patients without surgery.

Adolescent↗

PubMed2002

[Anesthetic experience for carotid endarterectomy in a patient with dilated cardiomyopathy under jugular venous oxygen saturation monitoring].

A 73-year-old male with dilated cardiomyopathy was scheduled for carotid endarterectomy. General anesthesia was administered with intravenous propofol and fentanyl. Cardiac output and jugular venous oxygen saturations were continuously monitored during the operation to maintain adequate cerebral circulation. The jugular venous oxygen saturation was maintained at above 85% during the operation. The patient recovered smoothly without any neurological sequelae.

Aged↗

PubMed2002

[Comparative studies on activities on antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). III. Secular changes in susceptibility].

The bacteria (Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between August 2000 and July 2001. Then, the susceptibilities of these bacteria to various antimicrobial agents were examined, and the results were compared with those obtained between 1992 and 1999. Comparison was made by classifying strains isolated from patients into those in uncomplicated UTIs and those in complicated UTIs (including with or without indwelling catheter). E. faecalis showed good susceptibility to ampicillin (ABPC) and imipenem (IPM), and the MIC90s were 2 micrograms/ml. Also, E. faecalis showed good susceptibility to vancomycin (VCM). However, the MIC90, which was 2 micrograms/ml between 1992 and 1999, rose to 4 micrograms/ml in patients with complicated UTIs because the strains inhibited at 4 micrograms/ml increased more than before. The low susceptibility of S. aureus to arbekacin (ABK) in complicated UTIs, as shown in 1998 and 1999, recovered in 2000, and no strains inhibited at > or = 4 micrograms/ml were detected. E. coli showed good susceptibility to CTM (MIC90: 0.25-0.5 microgram/ml) and CZOP (MIC90: < or = 0.125 microgram/ml) and was not resistant to those. E. coli also showed good susceptibility to the other drugs except to penicillins. Decreases in susceptibility of E. coli to quinolones, ciprofloxacin (CPFX), and sparfloxacin (SPFX) were observed in the patients with complicated UTIs. The susceptibility of Klebsiella spp. to all drugs did not significantly change in 2000 and was generally good except to penicillins. Although the susceptibility of P. aeruginosa to carbapenems was notable, the MIC90 went up from 4 micrograms/ml to 16 micrograms/ml in complicated UTIs compared with those observed in the previous year.

Anti-Infective Agents, Urinary↗

PubMed2002

[Comparative in vitro activities of several antimicrobial agents against Helicobacter pylori].

Comparative in vitro activities of several antimicrobial agents against Helicobacter pylori were evaluated. Minimum inhibitory concentrations against 41 strains of H. pylori were determined by using E test. All 41 strains were isolated from gastric mucosa of patients suspected to have gastric ulcer. The ranges of MIC of amoxicillin was from 0.016 microgram/ml and less to 0.064 microgram/ml. The ranges of MIC of clarithromycin, erythromycin, and azithromycin were from 0.016 microgram/ml and less to 64 micrograms/ml, from 0.016 microgram/ml and less to more than 256 micrograms/ml, from 0.064 to more than 256 micrograms/ml, respectively. The ranges of MIC of ciprofloxacin, sparfloxacin, levofloxacin, norfloxacin were from 0.016 microgram/ml and less to 32 micrograms/ml, from 0.002 microgram/ml and less to more than 32 micrograms/ml, from 0.002 microgram/ml and less to more than 32 micrograms/ml, from 0.064 to more than 32 micrograms/ml, respectively.

Amoxicillin↗