PubMed Health⌕ Search

Biomedical subjects

M Kido

Publications and source records attributed to M Kido.

At least 19 recordsLinked to original sources
PubMed1992

Escherichia coli RecA protein modified with a nuclear location signal binds to chromosomes in living mammalian cells.

We tried to make a well-characterized bacterial protein function in mammalian cell nuclei. For this purpose we chose Escherichia coli RecA protein and fused its carboxy terminus to the nuclear location signal of SV40 large T-antigen by oligonucleotide-dependent modification of the gene. When injected into the cytoplasm, the modified RecA protein (T-RecA for the T-antigen signal) accumulated efficiently in the nuclei, whereas the wild-type RecA protein remained in the cytoplasm. The T-RecA protein retained its original in vivo activity, judging from the finding that uv-sensitive bacteria (recA- E. coli) became uv-resistant on transformation with the T-recA plasmid as well as the recA plasmid. For expression of the T-recA gene in mammalian cells, the 5' region was replaced by the chicken beta-actin promoter and Kozak's initiation signal. A high level of expression was observed when Chinese hamster ovary (CHO-K1) cells were transfected with this plasmid. Indirect immunofluorescence examination revealed that the T-RecA protein in nuclei of mammalian cells bound to chromatin.

Amino Acid Sequence↗
PubMed1992

Comparison of Ki-ras gene mutation among simultaneously occurring multiple urethan-induced lung tumors in individual mice.

Mouse lung tumors were induced in C57BL/6J(female) x A/J(male) F1 mice by a single s.c. injection of urethan. About 6 months later, multiple small-sized lung tumors were detectable in almost all mice. After a further 6 months, some of these tumors became larger than the rest. We examined whether there were any mutational differences among multiple lung tumors in a single mouse. Direct DNA sequencing of a separately amplified Ki-ras gene by polymerase chain reaction (PCR) was carried out with 25 DNA samples from multiple tumors in four mice. Twenty-four of 25 tumors (96%) had mutations at the codon 61 of the Ki-ras gene. The major mutations involved were either AT to GC transition (44%) or AT to TA transversion (44%) at the second base of codon 61. We compared the types of these gene mutations among the tumors from each of two mice from two different groups of siblings and then compared the two groups. Interestingly, in the first group of siblings, we detected CTA in 5/6 tumors in the first mouse and again CTA in 4/6 tumors in the second one. In the second group of siblings, we detected CGA in 5/7 tumors in one mouse and CGA again in 3/5 tumors in the second mouse. These results show that the pattern of Ki-ras codon 61 mutations in urethan-induced lung tumors is similar in tumors developing in siblings, suggesting that host factors have an effect on the carcinogen-induced mutational pattern. There was no major mutational difference between small and large tumors. The results suggested that other event(s) in addition to the mutation of the Ki-ras gene might play a role during the development of large-sized tumors.

Amino Acid Sequence↗
PubMed1992

A case-control study on occupational lung cancer risks in an industrialized city of Japan.

A hospital-based case-control study was conducted to evaluate occupational risks of lung cancer in an industrialized city of Japan. The lung cancer cases were obtained from 3 major hospitals in the city. The control group consisted of patients with a variety of diseases hospitalized in the same wards of the same hospitals as the cases. After matching on sex, 5-year age category and hospital, 144 cases and 676 controls comprised the study group. A self-administered questionnaire was used to obtain lifetime job histories and smoking status. The conditional logistic regression model was used to estimate relative risks after controlling for smoking and employment in other jobs. The workers in shipbuilding, ironworks and other plants (mostly chemical plants) showed statistically significant increases in lung cancer risk with relative risks of 6.18, 2.02, and 2.66, respectively. An increase in risk with the duration of employment was also observed in the "other plants" category. Building and road construction workers also showed increased relative risks, 1.95 and 1.79, but they were not significant. When the risk was evaluated on the exposure chemicals, the workers exposed to inorganic acids and bases had significantly increased risk. The workers exposed to asbestos, dust or organic chemicals also showed increased risk but the effects were not significant. The combined effect of smoking and employment in ironworks showed a good fit to an additive model, while that in the "other plants" category was closer to a multiplicative model.

Adenocarcinoma↗
PubMed1992

Determinant factor for clearance of ceramic fibres from rat lungs.

Deposition, clearance, retention, and durability of inhaled particles from lungs are known to be important factors for induction of pulmonary fibrosis or lung cancer. To study the deposition and clearance of alumina silicate ceramic fibres from the lung, male Wistar rats were exposed to ceramic fibre particles with a mass median aerodynamic diameter (MMAD) of 4.2 micron, for six hours a day, five days a week for two weeks. The average exposure concentration was 20.7 (standard deviation (SD) 4.5) mg/m3. The rats were killed at one day, three months, and six months after the end of exposure, and the fibre numbers and dimensions were measured with a scanning electron microscope. No significant differences in number and geometric mean length of residual ceramic fibres in the lungs were found between the groups. The geometric mean diameter, however, decreased according to the duration of the clearance period. These findings suggest that solubility of fibre contributes most in the clearance of the inhaled ceramic fibres from the lungs.

Animals↗
PubMed1992

Guinea pig model of immunologic asthma induced by inhalation of trimellitic anhydride.

We established a model of asthma induced by trimellitic anhydride (TMA) in guinea pigs and assessed the role of sensitization in the development of their bronchial hyperresponsiveness, and relationship between bronchial responsiveness and bronchial inflammation. Fourteen guinea pigs (sensitized group) were administered 1 mg/0.5 ml of trimellity 36-bovine serum albumin intramuscularly and 0.5 ml of complete Freund adjuvant on Day 1 as the priming dose. Booster doses were repeated on Day 15. By Day 28, all of the sensitized animals showed a high passive hemagglutination titer against trimellityl 14-ovalbumin. On Day 29, they were challenged by an inhalation of TMA (150 mg/m3) for 30 min, and respiratory resistance (Rrs) was monitored by the oscillation method. In all sensitized animals, Rrs increased immediately upon challenge and returned to baseline within 6 h. The bronchial reactivity to acetylcholine (Ach), measured 6 h after TMA challenge in the sensitized animals, increased significantly (p < 0.01) compared with that measured 24 h before challenge; that measured 24 h later was not different from that before challenge. There was also a significant difference (p < 0.01) in the number of eosinophils in the lamina propria and the epithelium 6 and 24 h after the challenge inhalation in the sensitized group. The increased airway responsiveness to Ach in the sensitized animals was correlated with an increase in the number of eosinophils in the lamina propria and the epithelium. These observations suggest that humoral antibody and eosinophils are involved in the pathogenesis of TMA-induced asthma.

Acetylcholine↗
PubMed1992

Effect of oral pretreatment with antibiotics on the hydrolysis of salicylic acid-tyrosine and salicylic acid-methionine prodrugs in rabbit intestinal microorganisms.

We examined the hydrolysis mechanism of salicylic acid-tyrosine (salicyl-tyrosine) and salicylic acid-methionine conjugate (salicyl-methionine) in rabbits by exploring their behavior following intraduodenal and intracecal administration (72 and 36 mumol/kg, respectively: salicylic acid equivalent). A large amount of salicyl-methionine was absorbed following intraduodenal administration of salicyl-methionine, without being metabolized to salicylic acid in the small intestinal mucosa. On the contrary, salicylic acid was detected in the blood following intraduodenal administration of salicyl-tyrosine, suggesting that salicyl-tyrosine was metabolized in the small intestinal mucosa. After oral pretreatment of rabbits with kanamycin sulfate (6 x 400 mg) or tinidazole (6 x 160 mg), the hydrolysis of salicyl-tyrosine and salicyl-methionine following intracecal administration was inhibited significantly, indicating that the intestinal microorganisms were responsible for the biotransformation of these prodrugs. Furthermore, in rabbits orally pretreated with both kanamycin sulfate and tinidazole, a significant inhibition of salicylic acid formation from salicyl-tyrosine and salicyl-methionine following intracecal administration was observed.

Animals↗
PubMed1992

[A case of small cell carcinoma of the lung with carcinomatous lymphangiosis-like shadow].

A 60-year-old man was admitted to our hospital on January 29, 1991 with dry cough, shortness of breath on exertion, appetite loss and abnormal shadows on chest X-ray. Chest X-ray on admission showed marked vascular shadows in both lung fields accompanied by left interlobar effusion. Chest CT showed thickening of vessels and bronchial walls with prominent interlobular septa in the subpleural regions. These findings suggested that the lesions were located in the peribronchial and perivascular interstitium and interlobular septa. Biopsy specimens of bronchial epithelium, lung tissue and right supraclavicular lymph nodes revealed small cell carcinoma (intermediate cell type). Because of the absence of lesions in other organs, the initial diagnosis was carcinomatous lymphangiosis of small cell carcinoma of the lung. However, the mild symptoms, normal arterial blood gas and good response to chemotherapy suggested the possibility of extensive small cell carcinoma of longitudinal spread type. Although small cell carcinoma of the lung is not a rare disease, this case suggests two possibilities. 1) Carcinomatous lymphangiosis of small cell carcinoma may have different symptoms, clinical course and prognosis from that of non-small cell carcinoma. 2) Carcinomatous lymphangiosis of small cell carcinoma may not be a clinical entity and in fact may simply represent extensive small cell carcinoma of longitudinal spread type.

Carcinoma, Small Cell↗
PubMed1992

[A case of sarcoidosis with primary acute pulmonary cavitation].

A 23-year-old man was admitted to our hospital on June 24, 1991, because of worsening chest X-ray findings of sarcoidosis. In August 1990, he was referred to our outpatient office, because of BHL and nodular lesions on chest X-ray film performed at his company 4 months earlier. At that time, serum ACE was elevated to 34.0 IU/l, and Ga scintigraphy showed abnormal uptake in bilateral lacrimal and salivary glands, mediastinal and hilar lymph nodes, and in the lung fields. TBLB specimen showed noncaseating epithelioid granuloma with giant cells and negative stains for acid-fast bacilli. Although it was planned to follow this patient without medication, he did not return to our outpatient department. In June 1991, because of worsening of lesions in the lung at annual checkup at his company, he was referred and admitted for steroid therapy. Chest X-ray film on admission showed BHL, multiple nodular lesions in both lung fields, and bullous change in the left upper lobe. Chest CT on admission showed three cavitating lesions within preexisting nodules. PPD skin test was negative, and sputum smears and cultures were repeatedly negative for pyogenic bacteria and acid-fast bacilli. Therapy was initiated with prednisolone 30 mg daily. Four months later, there was marked resolution of BHL and nodular lesions, and the cavitating lesions were no longer visible on chest X-ray film. From the clinical and radiological observations, it is concluded that the cavitating lesions in the present case were primary acute pulmonary cavitation in sarcoidosis, distinct from infection, bullae, or cystic bronchiectasis which are seen in the chronic and fibrotic stages of sarcoidosis.

Adult↗
PubMed1992

[Two cases of chronic respiratory failure in intravenous methylphenidate (Ritalin) abusers].

Marked obstructive ventilatory impairment and diffusion disturbance were noted in two intravenous methylphenidate (Ritalin) abusers. In one patient, chest radiogram demonstrated pulmonary emphysema accompanied by bullae and atelectasis, and spontaneous pneumothorax was also present. The primary finding in the other patient was interstitial shadows. Both patients began to note dyspnea during exertion after about 10 years of use. Since radiography also disclosed pulmonary emphysema in an ex-companion of Ritalin abuse, and since the onset was at relatively young ages, these pulmonary disorders are considered to have been a result of intravenous Ritalin abuse. Intravenous drug abuse should be considered in patients with precocious emphysema or obstructive ventilatory impairment accompanied by diffusion disturbance.

Adult↗
PubMed1992

[A case of psittacosis with migratory infiltrates].

A 56-year-old man with fever, headache, cough and sputum was admitted to another clinic. Chest X-ray examination revealed infiltrates in the upper lobe of the right lung. Cefem and aminoglycoside therapy was not effective, and the infiltrates migrated from the right upper lobe to the right middle and lower lobes and then to the left lung. He was transferred to our clinic, and laboratory data showed that CRP was 6+; ESR, 119 mm/1 h; WBC, 3000/mm3; and CAR, 512. The tentative diagnosis of atypical pneumonia was based on the positive agglutination test for Legionella pneumophila, and treatment with erythromycin, minocycline and rifampicin resulted in alleviation of symptoms and resolution of the infiltrates in the lungs. Complement fixation titer for Chlamydia was 128 at admission and was elevated to 512 after 2 weeks. Indirect fluorescent antibody for Legionella was negative. Transient liver dysfunction was also observed.

Humans↗
PubMed1991

Identification of a plasmid-coded protein required for initiation of ColE2 DNA replication.

The product of the rep gene of ColE2 is required for initiation of ColE2 DNA replication. The rep gene was placed under the control of the promoters, PL and PR, and the heat-labile cl857 repressor of bacteriophage lambda. The Rep protein was identified as a 35 Kd protein by the maxicell method in combination with heat-induced expression. The protein was efficiently expressed from these promoters in unirradiated cells and accumulated up to a few per cent of the total cellular proteins. It was partially purified (about 80% pure) and its properties examined. The amino acid sequence of the amino terminal portion of the partially purified protein agreed well with that predicted from the nucleotide sequence of the rep gene. One of the characteristic features of the rep gene is frequent usage of rare codons, especially those for arginine. The protein specifically stimulated replication of ColE2 DNA but not that of ColE3 DNA in crude cell extracts of Escherichia coli. Specific binding of the protein to plasmid DNA containing the origin region of ColE2 was demonstrated by the filter binding method. Neither endonuclease activity nor topoisomerase activity was detected by using ColE2 DNA.

Amino Acid Sequence↗
PubMed1991

A case of malignant fibrous histiocytoma in the lung--resembling recurrent pulmonary thromboembolism.

Malignant fibrous histiocytoma (MFH) can be classified as a pleomorphic mesenchymal sarcoma which occurs most commonly in the extremities and retroperitoneum. We report a very rare case of MFH presumably originating in the pulmonary artery and resembling recurrent pulmonary thromboembolism. MFH was suggested by transbronchial biopsy and confirmed by open lung biopsy. Obstruction of the right main pulmonary artery and stenosis of the left main pulmonary artery was confirmed by pulmonary angiography.

Adult↗
PubMed1991

Single breath assessment of bronchial responsiveness: a comparison with the astograph method.

Bronchial responsiveness to inhaled doubling concentrations of acetylcholine using the astograph and single breath techniques was assessed in 7 males and 11 females (mean age 22.7, SD = 2.05 and 21.2, SD = 1.11 years for male and female respectively) healthy volunteers. Eleven (61%) of the subjects had neither a history of allergy nor wheezes. Five (28%) had allergic rhinitis and two (11%) had asthma. Seven (64%) of the normal subjects, all asthmatic and subjects with allergic rhinitis responded to inhaled acetylcholine. Respiratory conductance (Grs) and the one second forced expired volume (FEV1) expressed as percentages of the baseline values were compared on a semilogarithmic scale against cumulative dose. In most subjects the pattern of the curves showed close similarities in the two methods. The bronchial sensitivity i. e. minimum cumulative dose of acetylcholine just sufficient to start a fall in the FEV1 and Grs (CminS and CminA respectively), showed good correlation (r = 0.750, P less than 0.01). The results indicate that bronchial responsiveness can be reliably assessed using the simple single breath method as well as the more complex astograph method.

Acetylcholine↗
PubMed1991

Decrease of gastrointestinal mucosal damage by salicyluric acid compared with salicylic acid in rabbits.

The gastrointestinal mucosal damage following the oral administration of salicylic acid or salicyluric acid was examined in rabbits using a scanning electron microscope. Six and 24 h after treatment with salicylic acid, morphological changes of gastric mucosa were recognized. In rabbits treated with salicyluric acid, however, severe damage in the gastric mucosa was not found after 24 h compared with the treatment with salicylic acid. Following the treatment with salicylic acid, some mucosal damage in the duodenum, jejunum and ileum was observed after 24 h. The surface character of the duodenal, jejunal, ileal, caecal and colonic mucosa were almost identical compared with the control following the treatment with salicyluric acid. It was reported that salicyluric acid is metabolized to salicylic acid by the intestinal microorganisms. From these results, it was suggested that prodrugs utilizing the metabolism of salicyluric acid to salicylic acid by intestinal microorganisms may be useful in reducing gastrointestinal mucosal damage.

Administration, Oral↗
PubMed1991

Experimental lung injury induced by trimellitic anhydride inhalation on guinea pigs.

Trimellitic anhydride (TMA) causes lung injury by inhalation exposure in humans. In order to investigate more precisely the mechanism of lung injury by TMA, an experimental animal model of TMA-induced lung injury was established. Guinea pigs were intramuscularly injected with trimellitylated bovine serum albumin (TM BSA) with complete Freund's adjuvant (CFA). Appreciable amounts of antibodies against TM epitopes were detected in the sera of these animals. Guinea pigs that were passively sensitized with anti-TM antisera as well as the actively immunized animals developed hemorrhagic pneumonitis after TMA inhalation. It is well recognized that hyperimmune antisera of guinea pigs contain two subclasses of IgG antibodies, IgG1 and IgG2, which are known as homocytotropic and heterocytotropic antibodies, respectively. To determine the role of these antibodies in the airway injury with alveolar hemorrhages, they were isolated by gel filtration and by ion exchange column chromatography, and the guinea pigs that were sensitized with each of these antibodies were exposed to TMA inhalation. The extent of lung injury in these animals was quantitatively determined by the measurements of lung extravasation of Evans blue dye injected intravenously after TMA inhalation. Significant increases in the extravasation of dye were observed in both animal groups sensitized with IgG1 and IgG2 antibodies. In addition, results obtained with heat-treated antisera and IgG1 antibody did not significantly differ from those obtained with untreated samples. These results suggest that the lung injury resulting from TMA inhalation exposure can be induced with humoral antibodies, not only IgG1 but also IgG2, and that at least two types of allergic reactions are involved in the pathogenesis of lung injury.

Alveolitis, Extrinsic Allergic↗
PubMed1991

Targeted introduction of a diphtheria toxin-resistant point mutation into the chromosomal EF-2 locus by in vivo homologous recombination.

We have introduced a specific point mutation into the gene for chromosomal elongation factor 2 (EF-2) in Chinese hamster ovary cells (CHO-K1) by in vivo homologous recombination. To obtain a selectable construct for gene-targeting, we modified a diphtheria toxin-resistant mutant EF-2 gene (Gly717 to Arg) by deleting its promoter and first exon so that homologous recombinants could be distinguished from randomly integrated transformants, and also by inserting a second positive selection marker, the neomycin-resistance gene, into the 3'-flanking region to increase the selective accuracy. More than 80% of the clones surviving after selection for resistance to both the toxin and neomycin were the desired homologous recombinants in which the wild-type, toxin-sensitive EF-2 gene was replaced by the modified gene giving resistance to both the toxin and neomycin. This result shows that the specific point mutation was co-introduced with a second selective marker into an endogenous chromosomal gene and that the modified gene was expressed.

Animals↗
PubMed1991

Novel inhibitors of superoxide anion generation, OPC-15160 and OPC-15161. Taxonomy, fermentation, isolation, physico-chemical properties, biological characteristics and structure determination.

A new inhibitor of superoxide anion generation by guinea pig macrophages, OPC-15160, was isolated from the culture broth of fungus Thielavia minor OFR-1561, and a more potent inhibitor, OPC-15161, was obtained as a major degradation product of OPC-15160. OPC-15161 was five times more active than the natural inhibitor and its IC50 value was 2.8 x 10(-5) M. The structure of OPC-15161 was elucidated by X-ray analysis to be 6-(1H-indol-3-ylmethyl)-5-methoxy-3- (2-methylpropyl)-2-(1H)-pyrazinone, 4-oxide and had a novel and highly functionalized pyrazine skeleton.

Animals↗