Search PubMed⌕ Search

Biomedical subjects

T Aoki

Publications and source records attributed to T Aoki.

At least 361 records · Page 20Linked to original sources
PubMed1998

Successful resection of a glomus tumor arising from the lower trachea: report of a case.

Tracheal glomus tumors are extremely rare. We present herein the case of a 43-year-old man with hoarseness who was found to have a glomus tumor arising from the lower trachea. Bronchoscopy and chest computed tomography revealed a polypoid mass in the membranous portion of the trachea just above the carina. The patient underwent successful tracheal sleeve resection and reconstruction. A pathologic diagnosis of a glomus tumor with clear surgical margins was subsequently confirmed, and the patient is well 20 months postoperatively with an intact anastomosis.

Adult↗
PubMed1998

Cartilage folding method for main bronchial stapling.

Bronchopleural fistula is one of the most severe complications of lung operations. To prevent bronchopleural fistula, we modified the stapling technique to include folding of both sides of the cartilaginous main bronchus. This reduces the tension at the center of the membranous portion of the airway. From 1991 to 1994, this technique was performed in 7 patients. Despite the fact that 4 of these patients received adjuvant therapy, none had development of a bronchopleural fistula.

Bronchi↗
PubMed1998

Increasing incidence of streptococcal impetigo in atopic dermatitis.

Streptococcal impetigo associated with atopic dermatitis has dramatically increased from 1989 to 1994 in outpatients visiting our hospital, totalling 174 cases. The most frequent causative agents were group A streptococci (Streptococcus pyogenes, 70.7%) followed by group G (19.5%) and group B (9.8%). Streptococcus was isolated singly in 28.2% of cases and in concomitant with Staphylococcus aureus (S. aureus) in 71.8%. Major clinical features of streptococcal impetigo, especially caused by group A streptococci, were non-bullous pustules with thick crusted ceiling. Impetigo caused by group G or B streptococci generally formed smaller sized pustules of fewer numbers. Impetigo was usually present, associated with severe eczematous lesions. Various degrees of fever were noticed in 32.8% (group A, 39.8%; group G, 17.6%; group B, 11.8%) during active stages. The lesions on the face often resembled Kaposi's varicelliform eruption in any group. Systemic antimicrobial agents were administered in 71.3% of cases and the remainder were treated with topical antibiotics (oxytetracycline hydrochloride) or disinfectants (povidone-iodine). Recurrence occurred within a month in 38.0% of cases treated with topical agents only and in 17.7% treated with systemic antimicrobial agents. Antimicrobial susceptibility tests and the results of treatment seem to indicate that cephems, as well as penicillins, are the first choice of treatment for streptococcal impetigo.

Adolescent↗
PubMed1998

Video-assisted thoracic surgery (VATS) lobectomy: the Japanese experience.

Between September 1992 and October 1997, we performed 128 video-assisted thoracic surgery (VATS) lobectomies. The indications for surgery were 103 cases of lung cancer, 11 cases of bronchiectasis, 8 cases of granuloma, 4 cases of benign lesions, and 2 cases of metastatic tumors. Of the 103 cases of lung cancer, 62 were treated by VATS lobectomy with extended lymph node dissection for clinical stage I lung cancer, and the 4-year survival rate of final stage I lung cancer was 94.4%. VATS lobectomy is far less invasive than open thoracotomy, and survival rates after VATS lobectomy with extended lymph node dissection are comparable with those after open thoracotomy. Thus, VATS lobectomy with extended lymph node dissection should be considered as a standard surgical alternative to open thoracotomy for stage I lung cancer.

Adult↗
PubMed1998

1alpha,24-dihydroxyvitamin D3 (tacalcitol) is effective against Hailey-Hailey disease both in vivo and in vitro.

We report a case of Hailey-Hailey disease (HHD) in which 1alpha, 24-dihydroxyvitamin D3 (tacalcitol) was effective both clinically (in vivo) and in explant cultures (in vitro) of a skin lesion. The patient was a 65-year-old man with HHD lesions in the axillary and inguinal areas bilaterally. We applied ointment containing 1alpha, 24-dihydroxyvitamin D3 (tacalcitol), an analogue of active vitamin D3, to the lesions and assessed its clinical effectiveness. The HHD lesions in both groins disappeared after treatment with the 1alpha, 24-dihydroxyvitamin D3 ointment, and the remission has continued to the present. A punch biopsy specimen of the lesion that had remitted showed no acantholysis. In addition, dissociation of migrating keratinocytes was observed when biopsy specimens of the HHD skin lesion were cultured in medium without 1alpha,24-dihydroxyvitamin D3, but inhibition of keratinocyte dissociation was observed in medium containing it. These results suggest the effectiveness of 1alpha, 24-dihydroxyvitamin D3 against HHD both in vivo and in vitro.

Aged↗
PubMed1998

Note: molecular cloning of chitinase genes from Vibrio anguillarum and V. parahaemolyticus.

Chitinase genes from Vibrio anguillarum KV9001 and V. parahaemolyticus ATCC17802 were cloned into Escherichia coli. Open reading frames of chitinase genes from V. anguillarum (vac) and V. parahaemolyticus (vpc) are 1755 bp and 1890 bp, respectively. The deduced amino acid sequences of these genes have 71.6% identity. There are two consensus sequence regions in the VAC and VPC proteins. The vac gene was highly prevalent in V. anguillarum, and the DNA probe of the vac gene hybridized to V. alginolyticus and Beneckea proteolytica DNA. The DNA probe of the upc gene hybridized to V. alginolyticus, V. harveyi and V. ordalii DNA.

Amino Acid Sequence↗
PubMed1998

An autopsied case of Creutzfeldt-Jakob disease with the lateral geniculate body lesion showing antagonizing correlation between periodic synchronous discharges and photically induced giant evoked responses.

We reported an necropsy finding of a patient with Creutzfeldt-Jakob disease (CJD) who showed photo-stimulated giant spikes that simultaneously suppressed periodic synchronous discharges (PSD) and the loss of pupillary light reflex during the course of the illness. The necropsy revealed extensive gray and white matter lesions, and both the lateral geniculate body (LGB) and pregeniculate body were primarily affected. The superior colliculus, optic nerve and tracts were not affected. The cerebral cortices particularly of the occipital lobe were severely damaged. The Gennari line, however, was spared from lesion. The primary involvement of the LGB has been reported infrequently in CJD, however, it appears to be associated with the unusual electroencephalograph (EEG) feature of the present case. The pregeniculate lesion contributed to the loss of pupillary reflex. This finding indicates that the visual pathway may be involved in the mechanism of the generation of PSD in CJD.

Action Potentials↗
PubMed1998

Purification of recombinant human pepsinogens and their application as immunoassay standards.

Human pepsinogen (PG) A and C were cloned in Escherichia coli, but the levels of expression were low and unstable. When there were fused to maltose-binding protein (MBP), the fusion proteins (MBP-PGA and MBP-PGC) were expressed as the major products. Although these fused products were almost totally recovered from the insoluble fraction, the renaturation and purification procedures were easy and simple. MBP-PGA and the PGA segment obtained by factor Xa digestion (designated as r-PGA) possessed proteolytic activities equivalent to native PGA purified from gastric tissue (t-PGA). For PGCs (MBP-PGC, r-PGC and t-PGC) also, the specific activities were almost the same. However, the activities of PGCs were about 3- to 4-hold higher than those of PGAs. In PGA and PGC immunoassay systems, r-PGs (r-PGA and r-PGC) and the EIA kit standard PGs (gastric mucosal PGs) exhibited a good correlation. From these results, r-PGs would seem to be applicable as assay standards without compromising the sensitivity of the immunoassay systems.

ATP-Binding Cassette Transporters↗
PubMed1998

Detection of blotted antigen using a fusion protein between protein A and pepsinogen C.

Human pepsinogen (PG) A and C were fused with protein A and expressed in Escherichia coli. Although the fusion proteins (PA-PGA and PA-PGC) were not expressed at high levels and were almost totally recovered from the insoluble fraction, the renaturation and purification procedures were easy and simple. PA-PGA and PA-PGC possessed proteolytic activity equivalent to the gastric mucosal PGA and PGC, respectively. However, the activity of PA-PGC was about 3-fold higher than that of PA-PGA. Therefore, PA-PGC was applied to the subsequent immunoblotting studies. The proteolytic activity of PA-PGC was used for digesting the blocking reagent around the target antigen (in situ digestion method) or casein-clotting in the agarose plate containing skimmed milk (caseogram print method). Although the sensitivity of these methods was lower than that of the conventional color detection, the caseogram print method was superior in that the reaction was linear over a wide range. On the other hand, the in situ digestion method possessed a unique property on Western blotting, and it was very easy to identify the relative position of the target, which could be recognized as a clear band. For PA-PGC detection, no special chemicals are required, and so the procedure is simple, rapid, and inexpensive.

Antigens↗
PubMed1998

Caveolae: from a morphological point of view.

Caveolae in the plasma membrane have been a focus of intensive research during the past several years. There has been confusion concerning caveolae and caveola-like membrane domains, but it is now generally thought that the latter is a region distinct from caveolae. However, due to similar buoyancy of caveolae and caveola-like membranes, whether caveolae in situ are enriched with a given molecule is often difficult to be concluded by biochemical techniques alone. Furthermore, relatively shallow caveolae may be detected by some techniques, but not by others. Thus whether a molecule is enriched in caveolae should be confirmed by methods based on different principles. Among many putative caveolar molecules, those related to Ca2+ influx and extrusion were shown to be concentrated in caveolae by both immunocytochemical and biochemical techniques. In conjunction with other characteristics, the result implies that caveolae may function as a mobile compartment for Ca2+ signalling.

Animals↗
PubMed1998

Effects of oxyhemoglobin on vasoconstriction in response to 5-hydroxytryptamine in isolated, perfused canine basilar arteries.

OBJECTIVE: Oxyhemoglobin (OxyHb) is thought to be a critical trigger in the pathogenesis of cerebral vasospasm after aneurysmal subarachnoid hemorrhage. We investigated whether extraluminally applied OxyHb influenced vascular responses to intraluminally applied vasoactive agents in isolated, perfused, canine basilar arteries. METHODS: The steel cannula insertion method was used to examine vascular responses to intraluminally applied 5-hydroxytryptamine (5-HT) receptor agonists, i.e., 5-HT, 5-carboxamidotryptamine (selective for 5-HT1 receptors), and alpha-methyl-5-hydroxytryptamine (selective for 5-HT2 receptors), potassium chloride, and acetylcholine, before and after extraluminal treatment with OxyHb. RESULTS: Extraluminal application of 2.5 x 10(-5) mol/L OxyHb immediately induced a transient elevation of the basal perfusion pressure, which gradually decreased and then stabilized at a level slightly higher than the control level. Each 5-HT agonist induced dose-dependent vasoconstriction. The potencies of the agonists were not very different, but the efficacies varied, i.e., alpha-methyl-5-hydroxytryptamine > 5-HT > 5-carboxamidotryptamine. Each response was strongly inhibited by ketanserin (a selective 5-HT2 receptor antagonist), indicating that each agonist induces vasoconstriction mediated by 5-HT2 receptors. The vasoconstriction in response to each 5-HT receptor agonist was consistently potentiated by treatment with OxyHb (2.5 x 10(-5) mol/L). 5-HT receptor agonist-induced constrictions after OxyHb treatment were much more markedly inhibited by ketanserin, compared with those before OxyHb treatment. Acetylcholine-induced constrictions were enhanced by OxyHb, but KCl-induced constrictions were significantly decreased by OxyHb. CONCLUSION: It is suggested that OxyHb enhancement of constrictions in response to 5-HT receptor agonists may be mediated by increased sensitivity of 5-HT2 receptors, in addition to actions in the endothelium, in canine basilar arteries. This potentiated vasoconstrictor mechanism may be partially implicated in cerebral vasospasm after subarachnoid hemorrhage.

Animals↗
PubMed1998

Induction of granulomas in interferon-gamma gene-disrupted mice by avirulent but not by virulent strains of Mycobacterium tuberculosis.

To gain a better understanding of the pathological role of interferon-gamma (IFN-gamma) in specific granuloma formation, IFN-gamma gene-deficient mice (BALB/c and C57BL/6) were produced. The IFN-gamma gene in embryonic stem (ES) cells was disrupted by inserting the beta-galactosidase gene (lacZ) and the neomycin resistance gene (neo) at the translation initiation site in exon 1 by homologous recombination. Six-week-old IFN-gamma-deficient and wild-type mice were inoculated with 10(3)-10(7) bacilli of various strains of Mycobacterium tuberculosis (Kurono, H37Rv, H37Ra and BCG Pasteur) through their tail veins. The mice were examined 7 weeks later for granuloma formation. The avirulent BCG Pasteur and H37Ra strains (10(3)-10(4) bacilli/ml) induced granulomas in the spleen, liver and lungs of IFN-gamma-deficient mice. The granulomas consisted of epithelioid macrophages and Langhans multinucleate giant cells, but lacked caseous necrosis. The virulent Kurono and H37Rv strains induced disseminated abscesses but not granulomas in various organs of IFN-gamma-deficient mice and Mac-3-positive macrophages were not detected in the abscess lesions. These results suggest that IFN-gamma may be primarily responsible for macrophage activation and that other factor(s) may be involved in the granuloma formation mechanism.

Animals↗
PubMed1998

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits.

BACKGROUND: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1. METHODS: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation. RESULTS: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents. CONCLUSIONS: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.

Anesthetics, Inhalation↗
PubMed1998

Ulcerative colitis with skip lesions at the mouth of the appendix: a clinical study.

OBJECTIVE: We examined the clinical characteristics of ulcerative colitis patients who demonstrated endoscopically discontinuous lesions at the mouth of the appendix. METHODS: Of patients with initial or recurrent active ulcerative colitis who underwent total colonoscopy during the past 3 yr at Osaka City General Hospital, we selected those who had skip lesions in the mouth of the appendix before treatment, and examined their gender, age, disease type, sites of lesions, inflammatory reaction, severity of disease, effects of treatment, and posttreatment course. RESULTS: Discontinuous lesions at the mouth of the appendix were found in 10 patients, who had the following common clinical features: the major lesion was usually present in the lower part of the large bowel including the rectum, many of the patients had suffered an initial attack only, all patients had mild disease, and many of the patients responded quite satisfactorily to treatment with salicylazosulfapyridine. CONCLUSION: Numerous patients with ulcerative colitis with discontinuous lesions at the mouth of the appendix were observed and their clinical characteristics were examined. Determination of the clinical significance of skip lesions in the appendix will contribute to elucidation of the pathogenesis of ulcerative colitis.

Adult↗