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Biomedical subjects

K Konno

Publications and source records attributed to K Konno.

At least 307 records · Page 17Linked to original sources

[A case of aortitis syndrome which presented coarctation of aorta due to intraluminal flap formation in the middle of the thoracic aorta].

We present a rare case of aortitis syndrome associated with dilatation of aorta and coarctation-like effect due to the intraluminal flap formation originated from dissected wall of the aorta. A 31-year-old woman was admitted to our hospital complaining of shortness of breath, palpitation and cough. On admission, her physical status showed congestive heart failure and hypertension of upper extremities and hypotension of lower extremities. Bruits were audible over the neck, the anterior chest and the back. Serological studies showed active inflammation. Chest X-ray film showed upper mediastinal widening, cardiomegaly and pulmonary edema. Aortitis syndrome was strongly suggested by these clinical findings, so that prednisolone therapy was started on 3rd hospital day. Special examinations were performed several days later when inflammatory changes showed a tendency to improve. Chest CT scan, RI angiography and MRI studies showed an aneurysmal dilatation from the ascending aorta to the mid-thoracic aorta. Aortography demonstrated a flap at the terminal portion of this aneurysmal dilatation and grade II (Sellars) aortic regurgitation. There was a pressure difference of 80 mmHg between the parts abutting cranial and caudal sides of the flap. A surgical operation was, then, performed to correct the pressure difference. The dissected wall was extruded toward the aortic lumen creating a flap (2 cm in length). This flap was resected and an artificial graft was inserted. Histologically, the flap consisted of adventitia, media and intima.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Respiratory muscle fatigue].

To estimate the effect of the increase in ventilation induced by exercise on the dynamics of respiratory muscle in normal subjects and cases of respiratory diseases, we measured the changes of transdiaphragmatic pressure (Pdi), gastric pressure (Pga), tension time index of the diaphragm (TTdi) and tension time index of the abdomen (TTab). To confirm the effect of oxygen on exercise endurance, we investigated changes of parameters measured during exercise under air breathing and oxygen inhalation. In normal subjects, we found the increase in diaphragmatic activity as a gradual increase of exercise level, but TTdi always stayed in the non-fatigue zone. On the contrary, patients with COPD showed that TTdi was near fatigue threshold during quiet breathing and crossed easily into fatigue zone during exercise. There was an increase in endurance time with oxygen for COPD patients. Breathing with oxygen was associated with a smooth increase in Pdi during the inspiratory phase which indicates efficient contraction of the diaphragm. During the expiratory phase, the degree of increase in Pga was markedly reduced by oxygen inhalation.

Diaphragm↗

[A case of bronchobronchiolitis obliterans with Castleman's lymphoma].

The aim of this paper is to report a very rare case of bronchobronchiolitis obliterans accompanied by mesenteric Castleman's lymphoma. A 45-year-old woman was admitted to our hospital with progressive exertional dyspnea. Chest radiography showed overinflated lungs suggesting emphysema and pulmonary function tests revealed severely restrictive as well as obstructive impairments. Selective alveolobronchogram and endoscopy using a thin fiberoptic bronchoscope (3 mm in diameter) demonstrated multiple obstructions of small bronchi. Using a biopsy forceps, a small piece of tissue of bronchial wall was obtained from the focus of obstructive change, which showed histologically nonspecific inflammatory change including granulation. Therefore, we diagnosed her disease as bronchobronchiolitis obliterans (BBO). In addition, she had a large abdominal mass. On operation, it was found to be located in the mesenterium. It was then removed and the histological examination revealed Castleman's lymphoma, hyaline-vascular type. After operation, the blood IgM level, which was high on admission decreased rapidly and her dyspnea was reduced, suggesting that Castleman's lymphoma was related to the pathogenesis of her respiratory disease.

Bronchiolitis Obliterans↗

Effect of fibroblast-derived differentiation inducing factor on the differentiation of human monocytoid and myeloid leukemia cell lines.

A fibroblast-derived differentiation inducing factor (F-DIF) purified from medium conditioned by a human fibroblast cell line (WI-26VA4) induced differentiation of human monocytic leukemia cell lines (U-937, THP-1) into cells with macrophage characteristics. F-DIF alone induced the differentiation of ML-1 cells only marginally, but it synergistically increased the differentiation when combined with TNF. Interferon-gamma, tumor necrosis factor, GM-CSF, interleukin-1 and interlukin-4 synergistically enhanced the differentiation of U-937 cells when combined with F-DIF.

Cell Differentiation↗

Serum doxapram and respiratory neuromuscular drive in normal man.

To investigate the means by which doxapram affects the control of ventilation, ventilatory function and P0.1 have been related to serum doxapram concentration during a 45-min infusion of doxapram hydrochloride in 7 healthy, conscious subjects under normoxic conditions. Serum doxapram concentrations increased during the infusion: 1.88, 2.48, 3.42, and 3.97 micrograms/ml after 5, 10, 30 and 45 min, respectively. The majority of significant changes in the measurements from the baseline were observed at 30 and 45 min: VE, VT, P0.1, P0.1/end-tidal CO2 tension, VT/Ti and blood pressure were increased, and end-tidal CO2 tension was decreased. No significant changes in Pdimax, Ti/Ttot, VE/P0.1, and P0.1/(VT/Ti) were observed. A correlation was observed between the % increases in P0.1 and VE and doxapram concentration, and between VE and P0.1. The doxapram-induced increase in VE appears to be caused by increased neural drive. It is related to the serum drug concentration in the conscious subject.

Adult↗

Mucociliary clearance in pulmonary vascular disease.

The mucociliary clearance function was studied by radioaerosol inhalation lung cinescintigraphy and its quantification in 8 patients with pulmonary vascular diseases; pulmonary embolism, 5 cases, and right pulmonary artery hypoplasia, pulmonary arteriovenous fistulas, aortitis syndrome, 1 case each. The mucociliary clearance function was found to be well maintained in pulmonary vascular diseases unless ventilation was disturbed. There was no difference in the mucociliary clearance function between pulmonary embolism and other pulmonary vascular diseases.

Adolescent↗

Thick filaments of fish myosin and its actin-activated Mg-ATPase activity.

1. Tilapia (Tilapia nilotica) myosin forms short, mini-filaments, and are easily disassembled upon addition of ATP showing no saturated activation in its actin-activated Mg-ATPase activity. 2. The presence of 5-10 mM MgCl2 allows tilapia myosin to form native thick-filaments and are resistant to ATP. 3. The rod portion of Tilapia myosin molecule is responsible for its characteristic filament forming ability. 4. The similar filament forming ability as Tilapia myosin was suggested for other fish myosins.

Actins↗

Structure and synthesis of a potent glutamate receptor antagonist in wasp venom.

A low molecular weight toxin isolated from the venom of the digger wasp Philanthus triangulum, first noted by T. Piek, is a potent antagonist of transmission at quisqualate-sensitive glutamate synapses of locust leg muscle. This philanthotoxin 433 (PTX-433) has been purified, chemically characterized, and subsequently synthesized along with two closely related analogues. It has a butyryl/tyrosyl/spermine sequence and a molecular weight of 435. Its two analogues, PTX-343 and PTX-334 (the numerals denoting the number of methylenes between the amino groups of the spermine moiety), are also active on the glutamate synapse of the locust leg muscle; PTX-334 was more potent and PTX-343 was less potent than the natural toxin. Such chemicals are useful for studying, labeling, and purifying glutamate receptors and may become models for an additional class of therapeutic drugs and possibly insecticides.

Animals↗

G-actin structure revealed by chymotryptic digestion.

The chymotryptic digestion of G-actin in the presence of calcium produces not only a C-terminal 33 kDa "core," spanning from residue 68 to the C-terminus, but also an N-terminal Cys-10-containing fragment (10 kDa fragment), spanning from the N-terminus to the 44th residue. The minimum calcium concentration required for producing just these two structures is 10(-7.5) M. In a Ca medium, the 10 kDa fragment remains attached to the 33 kDa core, and the 10 kDa fragment detaches when the divalent cation is removed from the complex, as was proved by Sephacryl S-200 gel filtration. We conclude that 10 and 33 kDa form a complex that is calcium-sensitive. The Cys-10 in the 10 kDa moiety of the complex reacts with 5-iodoacetamide fluorescein in the presence of calcium ion, whereas Cys-257 is practically inert. The removal of calcium allows Cys-257 also to react with the reagent. Therefore, the complex seems to retain the calcium binding site. The nucleotide binding ability of the complex was also demonstrated.

Actins↗

Comparative activities of several nucleoside analogs against influenza A, B, and C viruses in vitro.

A set of 20 nucleoside analogs were examined for their inhibitory effects on the cytopathogenicity and growth of influenza virus type A, B, and C strains in Madin-Darby canine kidney (MDCK) cells. Among the compounds evaluated, pyrazofurin, 3-deazaguanine, ribavirin, carbodine, and cyclopentenyl cytosine inhibited viral cytopathogenicity at concentrations that were lower than those found cytotoxic for the MDCK cells. No differences were observed in the 50% effective doses (based on inhibition of viral cytopathogenicity) of these five compounds for a number of influenza virus type A (subtypes H1N1 and H3N2), B, and C strains. Pyrazofurin showed the lowest 50% effective dose (0.15 microgram/ml), which was about 20- to 30-fold lower than those of the other four compounds. The selectivity indices of the five compounds, calculated as the ratio of the 50% cytotoxic dose (determined by trypan blue exclusion) to the 50% effective dose, were greater than 100. When the selectivity indices were calculated as the ratios of the 50% inhibitory doses for cellular RNA synthesis to the 50% effective doses, they were greater than 100 for ribavirin, pyrazofurin, and 3-deazaguanine but less than 2 for carbodine and cyclopentenyl cytosine. All five compounds inhibited the growth of influenza virus types A and B in MDCK cells at a concentration which was well below their cytotoxicity threshold for MDCK cells and, therefore, deserve further exploration for their potential in the treatment of influenza virus type A, B, and C infections.

Cells, Cultured↗

In vitro activity of desacetylcefotaxime and the interaction with its parent compound, cefotaxime.

Antibacterial activities of cefotaxime and its major metabolite, desacetylcefotaxime, against 178 strains (of 10 species) were assessed in terms of minimum inhibitory concentrations (MIC50 and MIC80), and were compared with those of cefoperazone and ceftazidime. The activity of desacetylcefotaxime was several times less than that of cefotaxime against almost all of the species tested. Against Staphylococcus aureus, Morganella morganii, Enterobacter cloacae and Pseudomonas aeruginosa, the MIC80 values of desacetylcefotaxime were higher than those of cefoperazone and ceftazidime. The antibacterial potency of desacetylcefotaxime against Klebsiella pneumoniae and Pseudomonas cepacia was superior to that of cefoperazone and ceftazidime, and comparable with the activities of the latter compounds against the other 4 Gram-negative species. Partial synergy was demonstrated in the activity of cefotaxime and desacetylcefotaxime against most of the strains examined. Antagonism was observed in activity against 2 of 18 strains of M. morganii. In general, desacetylcefotaxime enhances the potency of its parent compound, cefotaxime, when they coexist. Intravenous infusion of cefotaxime 1 g over a period of 1 hour resulted in mean peak serum concentrations of 48.5 mg/L of cefotaxime and 6.5 mg/L of desacetylcefotaxime at the end of the infusion. The mean elimination half-life in beta-phase of cefotaxime was 0.8 hour and that of desacetylcefotaxime was 2 hours.

Bacteria↗

Epidemiologic studies on schistosomiasis japonica in a newly found habitat of Oncomelania snails in Japan.

Epidemiologic studies' on schistosomiasis japonica were carried out in the Obitsu River basin of central Boso Peninsula, a newly found habitat of Oncomelania snails in Japan. Forty-five (4.1%) of 1,102 schoolchildren and 64 (10.4%) of 618 junior high school students were positive for the skin test with veronal buffered saline-extracted Schistosoma japonicum antigen. None was positive by the enzyme-linked immunosorbent assay, complement fixation test, double diffusion test in agar, and circumoval precipitin test. About one fifth of 356 adult inhabitants showed positive reactions in the enzyme-linked immunosorbent assay and complement fixation test as well as in the skin test, although only 25 individuals (7%) were positive for the circumoval precipitin test. All of 70 individuals who had shown positive reactions in at least two of the immunological tests were negative for a series of 5 stool examinations with the AMS III method. Release of S.japonicum cercariae was not observed in 15,000 O. hupensis nosophora collected in this area. Repeated examinations by dipping mice into irrigation ditches were negative. These observations, with the fact that all of 15 patients reported from nearby hospitals to have schistosome eggs in their tissues were over 45 years old, suggest that schistosomiasis has become a disease of the past in this area.

Adolescent↗

[Clinical studies on S 6472 granule preparation (sustained-release cefaclor) in chronic respiratory tract infections].

S 6472 granule preparation (sustained-release cefaclor) was orally administered to 15 patients with chronic respiratory tract infections (2 acutely exacerbated cases of chronic bronchitis, 13 cases of secondary infections consisting of 1 case of bronchial asthma, 2 cases of bronchial asthma/pulmonary emphysema, and 10 cases of bronchiectasis) at a daily dose of 750 mg divided into 2 doses administered after breakfast and dinner, for a duration of 14 days. The drug was ineffective in 3 of the 10 cases of bronchiectasis but was effective in the other 12 cases, with a rate of efficacy of 80%. There were no side effects of abnormal laboratory findings due to administration of this drug.

Administration, Oral↗