Biomedical subjects

K Ueno

Publications and source records attributed to K Ueno.

At least 91 records · Page 5Linked to original sources

PubMed1999

Embryonic silk gland development in Bombyx: molecular cloning and expression of the Bombyx trachealess gene.

We describe embryonic development of the Bombyx silk gland. To extend the analysis further we isolated a Bombyx counterpart gene of the Drosophila trachealess (trh) gene. Bombyx trh encodes a protein of 849 amino acids. When compared with the amino acid sequence of Drosophila trh, the identity of Bombyx bHLH, PAS-A and PAS-B domains is 100%, 97%, and 80%, respectively. Northern blot analysis revealed the presence of a single Bombyx trh transcript of 5.4 kb. We analyzed the expression pattern of the Bombyx trh transcript during embryogenesis by in situ hybridization. Bombyx trh mRNA was first detected in the tracheal primordial cells at around embryonic stage 18. Thereafter levels of Bombyx trh mRNA increased, and the high expression level was maintained until hatching. At embryonic stage 19 the transcript was also detected in the posterior basal region of the labial segment from where the silk gland invaginates. By the blastokinesis stage (around stage 23), the silk gland was lengthened, and, interestingly, the Bombyx trh transcript was restricted to the anterior silk gland. These results suggest that Bombyx trh plays a role in the formation of the trachea and the anterior silk glands.

Animals↗

PubMed1999

Role of bipolar electrogram polarity mapping in localizing recurrent conduction in the isthmus early and late after ablation of atrial flutter.

OBJECTIVES: Bipolar electrogram polarity was analyzed to localize the recurrent conduction site in the isthmus between the tricuspid annulus (TA) and inferior vena cava (IVC) in recurrent atrial flutter (AF). BACKGROUND: Despite the initial successful linear isthmus ablation, recurrence of transisthmus conduction and AF is not uncommon. It is unclear how the recurrent conduction site can be identified. METHODS: Fourteen patients with recurrent AF were studied: four with late recurrence remote from the first ablation and 10 with early recurrence within 60 minutes after the initial successful ablation. Bipolar electrogram polarity mapping was performed during low lateral right atrium (LLRA) pacing during sinus rhythm while recording bipolar electrograms from the septal portion of the isthmus along the previously ablated line. The septal side of the isthmus from TA to IVC was arbitrarily divided into five sites, and the bipolar electrodes with cathode at the tip and anode at the second was placed at each site. The recurrent conduction site was localized by analyzing the polarity of the bipolar electrogram recorded at each site. RESULTS: All recurrent AF was due to reentry around TA. During pacing from LLRA, as the mapping electrode was moved from TA to IVC side, the major polarity of the electrogram changed from negative to positive in all patients. A transitional electrogram with the equal amplitudes in positive and negative components was recorded between the sites showing mainly negative and positive electrograms, indicating electrogram polarity reversal at this site. Application of radiofrequency energy to this single site resulted in the elimination of transisthmus conduction in all patients with a single application in 11 patients and 2 or 3 in the remaining 3. CONCLUSIONS: Bipolar electrogram polarity mapping with attention to the polarity reversal point is useful for identifying and ablating the recurrent conduction site.

Adult↗

PubMed1999

Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS).

OBJECTIVES: This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA. BACKGROUND: It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established. METHODS: Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA. RESULTS: Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups. CONCLUSIONS: With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.

Aged↗

PubMed1999

Aging and salt-loading modulate blood pressure QTLs in rats.

To evaluate the effects of nongenetic factors, aging, and salt-loading on the quantitative trait loci (QTLs) for blood pressure (BP), we conducted a genome-wide linkage analysis using multiple sets of BP measurements in 125 male F2 generation cross derived from stroke-prone spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. The experiment was arranged in two stages. In the first stage, corresponding to the developing period of the rats, BP was measured repeatedly without loading of salt; this continued until the rats were 5 months of age. In the second stage, after the baseline BP leveled off, 1% salt water was given to the rats and BP was monitored for the subsequent 7 months. Genome scanning was performed using 201 markers. In the developing period, three QTLs were identified on chromosomes 1, 3, and 4 (logarithmic odds [LOD] scores of 5.6, 3.1, and 3.2, respectively), which had peaks at 8 or 10 weeks of age. In the latter salt-loading stage, QTLs for BP were detected on chromosomes 1 and 10 (LOD scores 4.6 and 4.5, respectively). When the BP increase during salt-loading was analyzed as a phenotype, however, only the region on chromosome 10 showed linkage at a suggestive level (LOD score 3.2). The present study provides experimental evidence that QTLs for BP could be modulated by nongenetic factors, such as aging and salt-loading.

Aging↗

PubMed1999

Serum soluble interleukin-2 receptor levels before and during interferon treatment in patients with chronic hepatitis B virus infection.

To determine the role of serum soluble interleukin-2 receptor (sIL-2R) in chronic hepatitis B virus (HBV) infection, the level of serum sIL-2R was measured in sera of 105 patients with chronic HBV infection and in 21 healthy controls, using enzyme-linked immunosorbent assay. Serum sIL-2R levels were significantly higher in chronic HBV-infected patients with chronic hepatitis (508+/-310 units/ml) and liver cirrhosis (543+/-283 units/ml) than in healthy controls (331+/-106 units/ml, P < 0.05). Moreover, serum sIL-2R levels were significantly higher in patients with chronic hepatitis or liver cirrhosis than in asymptomatic HBV carriers (341+/-150 units/ml, P < 0.01). There was no difference in serum sIL-2R levels between asymptomatic HBV carriers and healthy controls or between patients with chronic hepatitis and liver cirrhosis. A significant relationship was found between serum sIL-2R and ALT levels (P < 0.05) in patients with chronic HBV infection, although there was no correlation between sIL-2R and HBV DNA levels. Serum sIL-2R levels in most patients decreased to the same level as asymptomatic HBV carriers and healthy controls at 48 weeks after the end of treatment, and serum ALT and HBV DNA levels were decreased to within the normal range at 96 weeks. Thus, serum sIL-2R levels indicate the degree of liver damage among patients with chronic HBV infection. The serum sIL-2R levels one year after interferon administration may be a useful marker of determined at the effectiveness by this treatment.

Alanine Transaminase↗

PubMed1999

Clinical course of chronic hepatitis C virus infection is not influenced by concurrent hepatitis G virus infection.

To determine the effects of hepatitis G virus (HGV) infection on chronic hepatitis C virus infection (HCV) and to evaluate HGV response to interferon, we investigated HGV RNA by polymerase chain reaction in 247 Japanese patients with chronic HCV infection (166 men and 81 women; 124 had chronic hepatitis and 26 cirrhosis, and 97 hepatocellular carcinoma). HGV RNA was detectable in 22 (8.9%) patients, among whom 21 were men: this male predominance was statistically significant (P < 0.01). There were no differences in age, aminotransferase level, stage of liver disease, HCV RNA level by competitive polymerase chain reaction, genotype, or interferon response to HCV RNA between patients with HCV infection alone or with HCV/HGV coinfection. Sustained elimination of HGV RNA was found in 28.6% of the 14 treated patients with HCV/HGV coinfection. In the 14 treated patients, sustained elimination of both viruses was seen in two, HCV alone was eliminated in two, and HGV alone was eliminated in two. Aminotransferase level improvement by interferon treatment was associated with clearance of HCV, but not of HGV. Thus, HGV infection had no apparent effects on HCV infection, and the sensitivity of HGV to interferon is comparable to but independent of HCV.

Antiviral Agents↗

PubMed1999

Inhibition of virus-induced neuronal apoptosis by Bax.

The Bax protein is widely known as a pro-apoptotic Bcl-2 family member that when overexpressed can trigger apoptosis in multiple cell types and is important for the developmental cell death of neurons. However, Bax was found here to be a potent inhibitor of neuronal cell death in mice infected with Sindbis virus. Newborn mice, which are highly susceptible to a fatal infection with neurotropic Sindbis virus, were significantly protected from neuronal apoptosis and fatal disease when infected with a recombinant Sindbis virus encoding Bax. Deletion of the N terminus of Bax, which mimics cleaved Bax, converted Bax into a pro-apoptotic factor in vivo. As mice mature during the first week after birth, they acquire resistance to a fatal Sindbis virus infection. However, Bax-deficient mice remained very sensitive to fatal disease compared with their control littermates, indicating that endogenous Bax functions as a survival factor and contributes to age-dependent resistance to Sindbis virus-induced mortality. The protective effects of Bax were reproduced in cultured hippocampal neurons but not in cultured dorsal root ganglia neurons. These findings indicate that cell-specific factors determine the anti-apoptotic versus pro-apoptotic function of Bax.

Alphavirus Infections↗

PubMed1999

Transcatheter adrenal arterial embolization of cortisol-producing tumors. Two cases of Cushing's syndrome.

Transcatheter arterial embolization (TAE) was performed in 2 patients with Cushing's syndrome caused by adrenal adenoma by using a mixture of absolute ethanol and iohexol. In 1 patient successful suppression of the hypersecretion of cortisol has continued for 9 months after TAE without complications. However, in the other patient, TAE was discontinued due to marked hypertension and tachycardia induced by a massive release of catecholamines from the embolized "normal" part of the tumor-bearing adrenal gland during the procedure. These results suggest that it is important to perform TAE of only the arterial branches feeding the tumor.

Adenoma↗

PubMed1999

Comparative study of assays for prostate-specific antigen molecular forms.

BACKGROUND: The detection of prostate-specific antigen (PSA) molecular forms such as free PSA and PSA-ACT and the use of PSA molecular ratios, especially the percentage of free to total PSA, have been reported to improve the diagnostic accuracy of prostate cancer in the patients with slightly elevated serum PSA values. However, the correlation among the values of serum free PSA or PSA-ACT obtained in various assays remains unclear. METHODS: Serum free PSA and PSA-ACT values were detected with the following assays: Hybritech, DPC, EIKEN, Abbott, Roche and Can-Ag for free PSA and Dainippon, Chugai, EIKEN and Bayer for PSA-ACT. The data obtained with each assay were compared with Hybritech (free PSA) and Dainippon (PSA-ACT) as standards. RESULTS: The free PSA data obtained with the Hybritech, EIKEN, Abbott and Can-Ag kits were similar. The values obtained with the DPC and Roche kits showed a linear regression of y = ax + b with those obtained with the Hybritech, with a b value of zero and an a value of 1.20 and 1.57, respectively. The serum PSA-ACT values detected with the Dainippon and Chugai kits were identical. The equation for converting the data obtained with the EIKEN kits to the Dainippon value was 0.7636 x (EIKEN) + 0.1381. CONCLUSIONS: Serum free PSA and PSA-ACT values obtained with various assays were not necessarily the same. Some kits for the assay of free PSA and PSA-ACT gave the same serum values. The free PSA values obtained with the other kits could be converted using appropriate equations. The gamma-Sm values showed wide variations and were not considered suitable as a measurement of free PSA.

Humans↗

PubMed1999

Isolation and characterization of two 20S proteasomes from the endoplasmic reticulum of rat liver microsomes.

Two new forms of proteasomes, designated as the endoplasmic reticulum (ER) membrane-associated proteasome (ERa proteasome) and ER membrane-bound proteasome (ERb proteasome), were purified to homogeneity from 0.0125 and 2.5% sodium cholate extracts, respectively, of a rat liver microsomal fraction. SDS-PAGE analysis revealed that the purified ERa and ERb proteasomes were composed of multiple subunits similar to the cytosolic 20S proteasome. However, electrophoretic, structural and immunochemical differences between the ERa, ERb and cytosolic 20S proteasomes were observed on native PAGE, two-dimensional (2D) PAGE, and immunoblot analyses. Purification of ERb from a 2.5% sodium cholate extract of the trypsin-treated microsomal fraction yielded a trypsin-modified form of ERb (tERb), which lacked the C2 subunit at least. On the other hand, no ERa proteasome was obtained from the 0.0125% sodium cholate extract of the trypsin-treated microsomes, suggesting that ERa and ERb are ER membrane-associated and -bound proteasomes, respectively. The ERa, ERb, and cytosolic 20S proteasomes exhibited similar specificities as to peptide hydrolyzing activity, although differences in their activities were noted in the presence of SDS and phospholipid. With respect to the proteolysis of protein substrates, only the ERb proteasome cleaved beta-casein, and it also degraded reduced and carboxymethylated lysozyme considerably faster than the cytosolic 20S and ERa proteasomes. Collectively our results suggest that the ERa and ERb proteasomes may play roles in intracellular proteolysis distinct from that of the cytosolic 20S proteasome.

Amino Acid Sequence↗

PubMed1999

A case of renal juxtaglomerular cell tumor: usefulness of segmental sampling to prove autonomic secretion of the tumor.

A 27-year-old female patient had been treated for hypertension with conventional therapy for years, because renal vein renin levels failed to show lateralization in renal venous samplings and a renal juxtaglomerular cell tumor (RJGCT) had gone undiagnosed. Abdominal computed tomography revealed a mass at the middle of the right kidney. The right renal venogram demonstrated distinct segmental veins from the upper pole and from the middle and lower poles in the right kidney. On segmental renin sampling from each renal vein, the plasma renin concentration (PRC) of the segmental veins from the middle and lower poles was higher than that from other sites. We diagnosed RJGCT of the right kidney and performed right-sided nephrectomy. After the resection, the PRC rapidly decreased. Immunohistochemical studies using antihuman renin antibodies revealed positive staining of the tumor cells. It is an important strategy to make a segmental sampling at the site as close as possible to the RJGCT.

Adenocarcinoma↗

PubMed1999

Characterization of a facultatively psychrophilic bacterium, vibrio rumoiensis sp. nov., that exhibits high catalase activity

A novel facultatively psychrophilic bacterium, strain S-1, which exhibits extraordinarily high catalase activity was isolated from the drain pool of a fish product processing plant that uses H2O2 as a bleaching and microbicidal agent. The catalase activity of the isolate was 1 or 2 orders of magnitude higher than those of Corynebacterium glutamicum, Staphylococcus aureus, Pseudomonas fluorescens, and five other species tested in this study. The strain seemed to possess only one kind of catalase, according to the results of polyacrylamide gel electrophoresis of the cell extract. The optimum temperature for catalase activity was about 30 degreesC, which was about 20 degreesC lower than that for bovine catalase activity. Electron microscopic observation revealed that the surface of the microorganism was covered by blebs. Although the isolate was nonflagellated, its taxonomic position on the basis of physiological and biochemical characteristics and analysis of 16S rRNA sequence and DNA-DNA relatedness data indicated that strain S-1 is a new species belonging to the genus Vibrio. Accordingly, we propose the name Vibrio rumoiensis. The type strain is S-1 (FERM P-14531).

Journal Article↗

PubMed1999

Prevalence of enterotoxigenic Bacteroides fragilis in children with diarrhea in Japan.

In age-matched controlled studies performed in Japan, enterotoxigenic Bacteroides fragilis was isolated from 14.9% of 114 children aged 1 to 14 years with antibiotic-unassociated diarrhea (AUD) and 6.5% of 108 children aged 1 to 6 years with antibiotic-associated diarrhea (AAD). The difference in comparison with control children, was significant for AUD children but not AAD children.

Adenoviruses, Human↗

PubMed1999

Correlation between respiratory function and airway inflammation in asthma.

BACKGROUND: Eosinophilic airway inflammation is thought to be associated with airflow limitation and airway hyperresponsiveness. METHODS: Spirometry, peak expiratory flow (PEF) measurement, histamine challenge test, and sputum induction with hypertonic saline inhalation were performed in 70 asymptomatic patients with asthma who were treated with bronchodilators or an inhaled corticosteroid (beclomethasone dipropionate, 400-800 microg/day) or both for more than 2 months. The relationships between the sputum eosinophils, respiratory function, and airway responsiveness to histamine were investigated. RESULTS: Induced sputum was obtained from 53 patients. Although significant correlations between sputum eosinophils and forced expiratory volume in 1 s/forced vital capacity x 100% (FEV1%) or maximum expiratory flow at 25% of the forced vital capacity (V25) divided by height (V25/Ht) were observed, no significant correlations were found between sputum eosinophils and percent predicted PEF (%PEF) or airway responsiveness to histamine. Furthermore, airway responsiveness to histamine was not correlated with FEV1%, V25/Ht or %PEF. CONCLUSION: Single-point measurements of FEV1% and V25/Ht but not PEF or airway responsiveness to histamine correlate with the degree of airway inflammation evaluated indirectly with induced sputum.

Adult↗

PubMed1999

Congenitally corrected transposition of the great arteries with a patent foramen ovale in an 81-year-old man--a case report.

Congenitally corrected transposition of the great arteries is a rare cardiac anomaly with a poor prognosis. In this report, the authors describe an 81-year-old man admitted to the hospital with generalized fatigue, chest pain, and cyanosis. Computed tomography and cardiac catheterization revealed corrected transposition of the great arteries. Transesophageal echocardiography disclosed moderate right atrioventricular regurgitation and a right-to-left shunt across a patent foramen ovale during systole. Because this patient had no other congenital cardiac anomalies, the right-to-left shunt through the patent foramen ovale was thought to be the major cause of cyanosis.

Aged↗

PubMed1999

Solitary squamous papilloma of the bronchus associated with human papilloma virus type 11.

A 79-year-old female presented with persistent dry cough, and a chest radiograph showed a mass shadow in the right upper lung. Bronchoscopic examination revealed that the right main bronchus was severely obstructed by a polypoid tumor, which was diagnosed pathologically as squamous papilloma. After the failure of the attempted endobronchial snare to remove the tumor, right upper lobectomy was performed. The polymerase chain reaction (PCR) examination showed the presence of human papilloma virus type 11 DNA in the resected tumor, suggesting that this virus was the cause of this solitary squamous papilloma of the lung.

Aged↗

PubMed1999

[A case of acute disseminated encephalomyelitis accompanying Mycoplasma pneumoniae infection].

We report a 30-year-old man with acute disseminated encephalomyelitis (ADEM) accompanying Mycoplasma pneumoniae (M. pneumoniae) infection. He was admitted to our hospital because of headache, disturbed behavior, and unconsciousness following an upper respiratory tract infection on December 19, 1996. On admission, he was febrile (37.3 degrees C) and showed hypersomnia and neck stiffness. There were scattered rhonchi in both lungs. Cerebrospinal fluid (CSF) contained 19 white cells; the protein was 20 mg/dl and glucose 71 mg/dl (blood glucose 170 mg/dl); no organisms were seen or cultured. Cranial MRI showed multiple T 2-weighted hyperintense in the periventricular region of the cerebral white matter. M. pneumoniae antibody titer in serum was remarkably elevated. ADEM related to M. pneumoniae was suspected. Although intravenous methylprednisolone, piperacillin and clindamycin were administered, there was no subsequent improvement in the symptoms. Further MRI scan revealed extension of the inflammatory lesion. He had both pneumonia and he required mechanical ventilation. Since the end of the critical period, he has been in an akinetic mutism. We conclude that M. pneumoniae has to be considered as a possible cause of ADEM with severe respiratory symptoms.

Adult↗

PubMed1999

[Pathophysiology and strategy of shock in terms of tissue oxygen metabolism].

In both septic shock and hypovolemic shock, global oxygen consumption is characterized by the supply dependency phenomenon, which suggests tissue hypoxia. The conventional measurements of blood lactate level, oxygen delivery/oxygen consumption, and mixed venous oxygen saturation may not provide reliable information on the adequacy of tissue oxygenation. The intestinal mucosal villus is particularly vulnerable to a reduction in oxygen delivery because of the countercurrent mechanism. Intestinal mucosal hypoxia may have important clinical ramifications as it has been implicated in the etiology of bacterial translocation and cytokine synthesis. Gastric tonometry has been proposed as a simple, relatively noninvasive technique to detect occult tissue hypoxia. Since gastric intramucosal PCO2 is directly related to arterial PCO2, the gradient between gastric and arterial PCO2 is recommended as a sensitive and specific index of intestinal hypoperfusion. Although the effects of therapeutic interventions are far from consistent, dobutamine, but not dopamine, appears to increase intestinal mucosal blood flow in critically ill patients the most consistently. Further studies are needed to demonstrate the effects of other agents, such as angiotensin-converting enzyme inhibitor and vasodilator prostaglandins. Plasma volume expansion with colloid solution may improve the splanchnic microvascular blood flow. Older stored-blood transfusion, however, may lead to tissue hypoxia.

Animals↗