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Biomedical subjects

M Kondo

Publications and source records attributed to M Kondo.

At least 721 records · Page 40Linked to original sources
PubMed1993

Cultures of bovine tracheal epithelium with differentiated ultrastructure and ion transport.

Tracheal epithelial cells were grown on Nuclepore filters coated with human placental collagen. When grown immersed in medium containing fetal bovine serum, cells displayed an undifferentiated ultrastructure (no cilia and a cell height of approximately 10 microns). Short-circuit current (Isc) was approximately 1/10 that of the native epithelium. By contrast, when grown in hormonally defined, serum-free medium with an air interface, cells showed Isc equal to or greater than the original tissue, possessed cilia, and had a cell height of approximately 50 microns. Responses in Isc to mediators were similar to those of the original tissue, but differed from those of dog or human tracheal epithelium. Given the ready availability and low cost of the native tissues, bovine tracheal cultures grown in serum-free medium with an air interface should prove useful in studies of airway epithelial physiology.

Amiloride↗
PubMed1993

Sympathetic hyperinnervation protects vascular smooth muscle cells from necrosis in stroke-prone spontaneously hypertensive rats.

Sympathetic nerve fiber distribution and vascular smooth muscle morphology were investigated in the ophthalmic artery of stroke-prone spontaneously hypertensive rats (SHRSP) and were compared with those of normotensive Wistar Kyoto (WKY) rats at the age of 120 days. The distribution of fluorescent noradrenergic (NA) nerve fibers was examined by the glyoxylic acid method. The ophthalmic artery was divided into two portions according to the size of the outer diameter, that is into a proximal portion (above 100 microns) and a distal portion (30-70 microns). The distribution densities of noradrenergic nerve fibers were measured by quantitative image analysis using the Interactive Bild-Analyse System (IBAS). The distribution densities of NA nerve fibers in both portions of the ophthalmic artery were significantly higher (p < 0.01) in SHRSP than that in WKY rats. The difference in the density of NA fibers of the ophthalmic arteries between SHRSP and WKY rats was 1.9 times in the proximal portion and 1.5 times in the distal portion. The vascular smooth muscle cells of the ophthalmic arteries in SHRSP were observed by scanning electron microscope to examine the trophic effect of NA nerve fibers on the vascular smooth muscle cells. The smooth muscle cells of both portions of the ophthalmic arteries in SHRSP showed a smooth surface texture and no necrosis, and were very similar to those of WKY rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic Fibers↗
PubMed1993

In vivo and in vitro study of the effects of chlorpromazine on tooth mineralization in rats and mice.

The effects of chlorpromazine (CPZ) on tooth mineralization were examined using incisor dentine in adult rats and cultured tooth germs of mandibular first molars dissected from mouse embryos. CPZ (10, 50 and 250 mg/kg, s.c.) substantially inhibited dentine mineralization as evaluated by contact microradiographs. Plasma calcium and phosphorus concentrations were not decreased by CPZ (10 and 50 mg/kg). Physicochemical effects were not involved in the action of CPZ on the mineralization. In vitro experiments showed that CPZ (1 and 10 microM) inhibited mineralization and alkaline phosphatase (ALP) activity in the tooth germs. As CPZ has the properties of a calmodulin antagonist, the calmodulin antagonists W-7 and W-5 were also examined. Both inhibited mineralization and ALP activity in tooth germs; W-5 had less effect than W-7. These in vivo and in vitro findings suggest that CPZ inhibited cell-mediated mineralization in dentine without affecting the calcium-regulating system and physicochemical mineral deposition. In addition, calmodulin could be involved in cell-mediated mineralization.

Alkaline Phosphatase↗
PubMed1993

Is ST segment re-elevation associated with reperfusion an indicator of marked myocardial damage after thrombolysis?

OBJECTIVES: The significance of ST segment re-elevation at reperfusion by thrombolysis was evaluated. BACKGROUND: The significance of ST re-elevation has not been studied. Hence, we evaluated whether ST re-elevation is an indicator of marked myocardial necrosis after reperfusion. METHODS: Twelve-lead electrocardiograms were recorded serially, before thrombolysis and immediately after each coronary angiographic procedure during thrombolysis. RESULTS: In 32 patients with acute myocardial infarction, 15 showed transient ST re-elevation at reperfusion (group 1) and 17 showed reduction (group 2). Peak creatine kinase (CK) and CK-MB isoenzyme activity levels were significantly higher in group 1 than in group 2. Twelve patients in group 1 had strongly positive findings on early technetium-99m pyrophosphate scintigraphy, compared with one patient in group 2 (p < 0.001). The regional ejection fraction did not increase from the acute phase to the chronic phase in group 1. The ST deviation before thrombolysis was significantly greater in group 1 than in group 2 (p < 0.001). All 14 patients in group 1 showed Thrombolysis in Myocardial Infarction (TIMI) grade 0 flow and 12 of these patients did not have good collateral flow before thrombolysis. CONCLUSIONS: These data suggest that 1) ST re-elevation at reperfusion is a sign of limited myocardial salvage by thrombolysis, and 2) high ST elevation and TIMI grade 0 flow without good collateral flow before thrombolysis may be predictive variables for marked myocardial necrosis after reperfusion.

Aged↗
PubMed1993

Role of oxygen radicals in indomethacin-induced gastric mucosal microvascular injury in rats.

To investigate the pathogenesis of indomethacin-induced gastric mucosal injury, vascular injury was examined in the rat using Evans blue and monastral blue vascular tracers. Extravasation of intravenously injected Evans blue into the gastric mucosa was used as an indicator of vascular permeability. Monastral blue was used to demonstrate vascular injury morphologically. The extravasated content of Evans blue significantly increased and reached the maximum at 2 h after indomethacin administration. The increase in Evans blue content was significantly inhibited by the pretreatment with superoxide dismutase (SOD) and SOD + catalase, but not with catalase alone. Monastral blue-labeled damaged endothelial cells in the gastric mucosa also increased at 2 h after indomethacin administration, which increase was reduced by pretreatment with SOD and SOD + catalase. These results indicate that oxygen radicals, including the superoxide radical, play an important role in the microvascular injury induced by indomethacin, which in turn plays a primary role in the development of gross hemorrhagic erosions.

Animals↗
PubMed1993

Effect of sofalcone on gastric mucosal injury induced by ischemia-reperfusion and its antioxidant properties.

The effect of sofalcone on gastric mucosal injury induced by ischemia-reperfusion (I-R) injury was studied in rats. I-R injury was produced in rat stomach by applying a small clamp to the celiac artery for 30 min and by removal of the clamp for 60 min. The increase in total area of erosions in the stomach after I-R and the increase in lipid peroxides in the gastric mucosa were significantly inhibited by intragastric administration of sofalcone. In addition, sofalcone significantly inhibited the lipid-soluble free radical initiator-induced increase in lipid peroxides of the gastric mucosal homogenate, and could show scavenging action of superoxide radicals in aprotic solvent. These results showed that the protective effect of sofalcone against I-R-induced gastric mucosal injury is attributable to its antioxidant activities in the lipophilic phase.

Animals↗
PubMed1993

[Mutations of HIV-1 RT gene isolated from patients treated with AZT].

HIV-1 strains were isolated from three patients treated with AZT and from three patients not treated with AZT. Progenomes of HIV-1 RT gene were amplified by PCR and cloned to M13mp18 vecter. Four amino acid mutations in RT gene (Asp67, Lys70, Thr215, Lys219) associated with resistance to AZT were analysed. All of the 14 clones obtained from the three patients with AZT therapy had mutations at codon 215 (Thr-->Tyr or Phe). Some of the 14 clones also had other mutations at codon 67 (Asp-->Asn or Ser), codon 70 (Lys-->Arg) and codon 219 (Lys-->Glu). All of 18 clones obtained from the patients not treated with AZT have no mutation at any codon mentioned above.

Amino Acid Sequence↗
PubMed1993

[Investigation of AZT sensitivity of HIV-1 isolates from patients treated with AZT].

AZT sensitivity was investigated on 6 HIV-1 isolates by culture method. Three of the isolates derived from 2 patients treated with AZT and the others were isolated from patients not treated with AZT. Cultures of 2 isolates (005 and 038) from a patient not treated with AZT did not show cytopathic effect (CPE) in the presence of 0.1 microM or 1.0 microM AZT. Meanwhile, cultures of isolate (043) from a patient treated with AZT for 2 months showed CPE in the presence of 0.1 microM AZT. Furthermore, cultures of isolates from patients treated with AZT for 6 months (043-2) and for 4 months (091) showed CPE in the presence of 1.0 microM AZT. HIV-1 p24 antigen was not detected by ELISA in the supernatants of cultures which did not show CPE. However, HIV-1 p24 antigen was detected in the culture supernatants which showed CPE. These results demonstrated that isolates from patients treated with AZT contained AZT-resistant variants which could replicate in the presence of 1.0 microM AZT.

Adolescent↗
PubMed1993

[Reverse transcriptase gene analysis of HIV-1 mutants cultured in the presence of AZT].

HIV-1 strains were isolated from four patients treated with AZT for more than 6 months and from three patients untreated with AZT. Isolates from patients treated with AZT have been cultured by passage of virus in cell culture in the presence of 1 microM AZT. However the isolates from patients untreated with AZT could not be cultured in the presence of AZT. The RT gene of HIV-1 isolates which had been cultured in the presence of AZT were amplified by PCR and cloned to M13 vector. Four amino acid mutations in RT gene (Asp67, Lys70, Thr215, Lys219) associated with resistance to AZT were analysed. All of the 22 clones obtained from the isolates in the presence of 1 microM AZT had mutations at codon 215(Thr-->Tyr or Phe). Some of the 22 clones also had other mutations at codon 67 (Asp-->Ser), codon 70 (Lys-->Arg) and codon 219 (Lys-->Glu or Gln). Four amino acid residues in RT gene of the isolates which had been cultured in the presence of AZT were compared to that of the isolates cultured in the absence of AZT. The clones of the isolates obtained from the patients (04 or 05) had mutations at only codon 215 Thr-->Tyr) in both the presence and the absence of AZT. All of the clones of the isolates obtained from the patients (06 or 07) had mutations at codon 215 and some of them had other mutations.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Role of active oxygen, lipid peroxidation, and antioxidants in the pathogenesis of gastric mucosal injury induced by indomethacin in rats.

The roles of active oxygen, lipid peroxidation, and the antioxidative defence mechanism in gastric mucosal injury induced by treatment with indomethacin in rats were investigated. The total area of gastric erosions and concentration of lipid peroxides in the gastric mucosa increased with time after administration of indomethacin (20 mg/kg, orally). The alpha-tocopherol:total cholesterol ratio in serum was significantly decreased and the activity of glutathione peroxidase, an important enzyme to scavenger of lipid peroxides, was inhibited by the administration of indomethacin. Treatments with superoxide dismutase and catalase inhibited the increases in gastric mucosal erosions and lipid peroxides in the gastric mucosa, and the reduction of serum alpha-tocopherol. Treatment with these scavengers did not improve the decreased glutathione peroxidase activity. These findings suggest that active oxygen species and lipid peroxidation play an important part in the pathogenesis of gastric mucosal injury induced by indomethacin, and that the decreased glutathione peroxidase activity aggravated the injury due to accelerated accumulation of hydrogen peroxide and lipid peroxides in the gastric mucosal cell.

Animals↗
PubMed1993

Cryostat sectioning of formalin-fixed brain: further attempt to improve section quality by previous infiltration with O.C.T. compound.

We previously reported that in non-brain and formalin-fixed specimens, one can obtain frozen sections of markedly improved quality not only by supporting specimens with O.C.T. compound as usually done, but by infiltrating them with the medium prior to embedding. In the present paper we show that this technic also proved to be quite effective in the cryosectioning of brain tissues, which so far has been difficult because of the liability of sections to shattering, particularly when one attempts to obtain a thick section. The present paper also discusses about the reason why sectioning is improved by the procedure, and aims to establish the optimal temperature for cryostat sectioning in relation to section thickness.

Brain↗
PubMed1993

Selective IgM deficiency in a patient with Hashimoto's disease.

A 70-year-old man with Hashimoto's disease had selective IgM deficiency, while other immunoglobulin levels were normal. In vitro mixing experiments were carried out in which B cells and T cells from the patient and from a healthy control donor were co-cultured in the presence of pokeweed mitogen, in order to investigate the etiology of IgM hypoproduction. The results indicated that the patient had B-cell dysfunction, involving the impairment of B-cell differentiation. In addition, both IgG of the healthy control donor and thyroid hormone may play important roles in the pathogenesis of this case.

Aged↗
PubMed1993

Stage IA non-Hodgkin's lymphoma of the Waldeyer's ring. Limited chemotherapy and radiation therapy versus radiation therapy alone.

Seventeen patients with stage IA non-Hodgkin's lymphoma of the Waldeyer's were treated with radiation therapy with or without chemotherapy. All lesions were judged as having intermediate grade malignancy in the Working Formulation. Eight patients received combined treatment with three cycles of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) and radiation therapy with 30 to 40 Gy. Another 9 patients were treated with radiation therapy 40 to 60 Gy alone. After a median follow-up of 69 months, all 8 patients, treated with combined modality were alive and relapse-free, whereas 4 of the 9 treated with irradiation alone had relapsed. All relapses occurred trans-diaphragmatically. Two of the 4 relapsing patients were saved, but the other two died of the disease. The 5-year relapse-free and cause-specific survival rates were 100% and 100% in the combined modality group, and 56% and 76% in the radiation therapy alone group (relapse-free: p = 0.04, cause-specific: p = 0.16). There were no serious complications related to the treatment, although most patients complained of mouth dryness and most patients given CHOP had paresthesia. Our opinion was that the total impact of these two side-effects on quality of life was less pronounced after combined modality than after radiation therapy alone. Limited chemotherapy and radiation therapy seemed to be more beneficial than radiation therapy alone not only in relapse-free survival but also in quality of life after treatment.

Adult↗
PubMed1993

Megakaryocytic ploidy in myelodysplastic syndromes.

The megakaryocytic ploidy was microfluorometrically measured in 12 normal controls and 15 myelodysplastic syndrome (MDS) patients using DAPI (4',6-diamidino-2-phenylindole) staining after destaining of the Wright-Giemsa (WG) stain. MDS patients had slightly more immature megakaryocytes when compared with normal controls. The megakaryocytic ploidy distribution had a peak at 16N in normal controls, at 8N in the 11 of the 15 MDS patients, and at 4N in the remaining 4 patients, which is suggestive of impaired polyploidization in MDS patients. In MDS, micromegakaryocytes were shown not to be immature but much more impaired in polyploidization than non-micromegakaryocytes. However, there was no difference in the megakaryocytic ploidy pattern among the type of the modification of Feinendegen' classification in each case for both the normal controls and the MDS patients, suggesting that the megakaryocytic ploidy is probably determined at the maturation level of the megakaryoblasts or the precursor cells. The study of megakaryocytic ploidy before and after therapy in the case of refractory anemia with excess of blasts might suggest that the remission of MDS patients might be qualitatively different from that seen in acute leukemia patients. Furthermore, the DNA histogram of the megakaryocytes from one of the two MDS patients obtained by the new method, which is able to determine the amount of DNA in the immunologically identified megakaryocytes microfluorometrically, using the monoclonal anti-glycoproteins IIb/IIIa antibody on bone marrow smears, showed a shift towards small ploidy compared with those defined on the basis of WG staining. This finding indicates that the micromegakaryocytes or the megakaryoblasts which could not be identified morphologically can be identified immunologically.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Antioxidant properties of antiulcer Kampo medicines.

Kampo medicines, aqueous extracts of a mixture of natural crude drugs, have numerous ingredients. Recent pharmacologic studies on Kampo medicines have clarified their many and varied biological activities. In this study, based on recent research that has been directed toward the excellent antioxidant properties of Kampo medicines, we investigated antioxidant activities of three Kampo medicines (TJ-10, TJ-35, TJ-43), which are clinically used for gastritis or peptic ulcer, by the electron paramagnetic resonance (EPR) spin trapping method. These Kampo medicines, especially TJ-35 scavenged superoxide generated from the hypoxanthine-xanthine oxidase system, and slightly inhibited the superoxide generation from polymorphonuclear leukocytes stimulated by phorbol myristate acetate or opsonized zymosan. Three Kampo medicines, especially TJ-35 also inhibited the generation of hydroxyl radicals by the Fenton reaction. These results suggest that these antioxidant properties may be partly responsible for anti-ulcer actions of these three Kampo medicines, especially TJ-35.

Antioxidants↗
PubMed1993

Detection of free radicals in the blood of animals using extracorporeal circulation.

A method was designed to detect free radicals in circulating blood of animals using extracorporeal circulation and electron paramagnetic resonance (EPR). An arterial-venous shunt was inserted into male Wistar rats between the distal abdominal aorta and the inferior vena cava. The polyethylene tube of the shunt was flowed through a quartz EPR cell. The circulation was supported by manual pumping and maintained at a rate of 3 ml/min. No signal was detected in the blood of untreated rats. After a bolus injection of four spin labels, 2,2,6,6-tetramethyl-piperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethyl-piperidine-1-oxyl, 3-carbamoyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl, and 3-carbamoyl-2,2,5,5-tetramethyl-pyrroline-1-oxyl, signals from each were detected. The intensity of the signal decreased exponentially and the half time was 23.9, 21.6, 47.1, 42.4 sec, respectively. After administration of ascorbic acid, ascorbyl radical signals were detected. This was enhanced by ethylenediaminetetraacetic acid-Fe or diethylenetriaminepentaacetic acid-Fe but not desferrioxamine-Fe. This assay system is useful in detecting free radicals either administered or generated in vivo.

Animals↗
PubMed1993

Antioxidant therapy in digestive diseases.

This paper reviewed the recent advance in the antioxidant therapy for digestive diseases. Many reports have supported that lipid peroxidation mediated by oxygen radicals is implicated in the pathogenesis of gastric mucosal injury, intestinal damage, acute pancreatitis, and liver injury, and several kinds of antioxidant, which are divided into the preventive antioxidant and chain-breaking antioxidant, are effective in the treatment of these diseases. A new therapeutic approach using synthesized antioxidants, such as zinc-carnosine chelate compound and ebselen, has been also proposed in these fields.

Animals↗