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T Kojima

Publications and source records attributed to T Kojima.

At least 37 records · Page 2Linked to original sources
PubMed1992

Rotation vector, a new method for representation of three-dimensional deformity in scoliosis.

Rotation vector for three-dimensional deformity, a new concept in scoliosis, is presented. This vector quantifies three-dimensional deformity in scoliosis. Rotation vectors are calculated between pairs of end plates. Any three-dimensional malalignments (scoliosis, lordosis [or kyphosis] and rotation) existing between a pair of end plates should be cancelled perfectly by rotating one end plate against the other about an axis represented by the rotation vector. A rotation vector suggests how the deformity in scoliosis should be corrected three-dimensionally.

Adolescent↗
PubMed1992

Dual Bar homeo box genes of Drosophila required in two photoreceptor cells, R1 and R6, and primary pigment cells for normal eye development.

In the Bar mutation of Drosophila, ommatidial differentiation is known to be suppressed in the anterior portion of the eye. Our structural analysis shows that the Bar region contains a pair of homeo box genes, BarH1 and BarH2. These genes encode polypeptides similar in size and sequence and share a common homeo domain that is identical in sequence except for putative trans-activator-binding sites. We also show, by mosaic analysis and immunostaining with anti-BarH1/BarH2 antibodies, that BarH1 and BarH2 are not only specifically coexpressed but also functionally required in R1/R6 prephotoreceptors and primary pigment cells in developing ommatidia. In R1/R6, the expression of BarH1 and BarH2 appears to be regulated by rough and glass gene products. BarH1 and BarH2 proteins are essential to normal lens formation, formation of three types of pigment cells, and elimination of excess cells from mature ommatidia. Taken together, our results suggest that Bar homeo domain proteins may play key roles in the fate-determination processes of pigment cells and cone cells.

Amino Acid Sequence↗
PubMed1992

Inhibitory effects of the natural products indole-3-carbinol and sinigrin during initiation and promotion phases of 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis.

The modifying effects of indole-3-carbinol (I3C) and sinigrin (SIN) on the initiation and post-initiation phases of tongue carcinogenesis induced by 4-nitroquinoline 1-oxide (4-NQO) were investigated in male ACI/N rats. Rats were divided into eight groups: group 1 was given 4-NQO (10 ppm) in the drinking water for 12 weeks, starting at 7 weeks of age; groups 2 and 3 were given 4-NQO and fed the diets containing I3C (1,000 ppm) and SIN (1,200 ppm) for 14 weeks, respectively, starting at 6 weeks of age; groups 4 and 5 were given 4-NQO and then they were fed I3C and SIN containing diets for 23 weeks, respectively, starting one week after 4-NQO exposure; groups 6 and 7 were given I3C and SIN alone, respectively, during the experiment; group 8 served as an untreated control. At the termination of the experiment (week 37), the incidence of tongue neoplasms (squamous cell papilloma and carcinoma) in group 2 (1/15, 7%), group 3 (1/15, 7%), group 4 (3/15, 20%) or group 5 (2/15, 13%) was significantly smaller than that in group 1 (12/17, 71%) (P = 0.0003, P = 0.005 or P = 0.002). No tongue carcinomas developed in rats of groups 2, 3, and 5. Similarly, the incidence of preneoplastic lesions (hyperplasia and dysplasia) of the tongue in group 2 (11/15, 73%), group 3 (10/15, 67%), group 4 (11/15, 73%) or group 5 (10/15, 67%) was significantly lower than that in group 1 (17/17, 100%) (P = 0.04 or P = 0.02). There were no tongue neoplasms in rats of groups 6, 7, and 8. Administration of I3C and SIN also caused significant decreases in the number and area of silver-stained nucleolar organizer regions protein (AgNORs), a new cell proliferation index, of tongue squamous epithelium. Thus, I3C and SIN inhibited rat tongue carcinogenesis in both the initiation and post-initiation phases, when administered in these respective phases together with, or following treatment with, 4-NQO.

4-Nitroquinoline-1-oxide↗
PubMed1992

Disodium cromoglycate in the treatment of bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) has become the most common form of chronic lung disease in the neonate. Recently, we have experienced a severe case of BPD and examined the effect of disodium cromoglycate (DSCG) on BPD. The gestational age and birthweight of the patient were 27 weeks and 1,000 g, respectively. Although RDS subsided after surfactant replacement therapy, the arterial-alveolar oxygen tension ratio (a/APO2) gradually decreased and FiO2 increased with age, respectively, and pure oxygen supplementation was eventually required after 67 days of life. The DSCG treatment was commenced at 80 days of life. After 6 days of the inhalation therapy, a/APO2 gradually increased. After 10 days of the treatment, the baby was extubated. While the baby was intubated, intratracheal lavage fluid samples were obtained. Eosinophilic cationic protein (ECP) and polymorphonuclear (PMN) elastase concentrations were determined. ECP and PMN elastase concentrations of intratracheal lavage fluids gradually decreased with the DSCG treatment. These results may indicate that DSCG has led to an improvement of pulmonary function and facilitated weaning from mechanical ventilation in an infant with BPD.

Bronchoalveolar Lavage Fluid↗
PubMed1992

Clinical course of early fetal loss and its chromosomal characteristics.

The relationship between types of chromosomal abnormalities and fetal development documented by ultrasonography was discussed in early spontaneous abortions. The subjects were 113 patients who had vaginal ultrasonography at least twice between 6 and 8 weeks of pregnancy, among 167 abortuses with chromosome analyzed. The results were also compared against those for 303 normally developing fetuses. The results obtained in the present study suggested that each fetus with a chromosomal abnormality succumbed at or after a specific stage of fetal development and that the fetal death might be the results of severe fetal growth suppression.

Abortion, Spontaneous↗
PubMed1992

Circulating levels of endothelin and atrial natriuretic factor during postnatal life.

We determined plasma endothelin-1-like immunoreactivity and atrial natriuretic factor concentrations in preterm and full-term newborn infants during the first month of life. Plasma endothelin-1-like immunoreactivity levels were far greater than those of maternal blood in the newborn infants. The highest plasma endothelin-1-like immunoreactivity levels were observed on the first day of life (8.7 +/- 3.7 pmol/l) and gradually decreased with age. There was no significant difference in plasma endothelin-1-like immunoreactivity levels between preterm and full-term infants. A good correlation was observed between plasma endothelin-1-like immunoreactivity levels and atrial natriuretic factor concentrations (p < 0.01). These results suggest that circulating endothelin may regulate the cardiovascular system in the newborn period.

Atrial Natriuretic Factor↗
PubMed1992

Regulation of Na,K-ATPase gene expression by thyroid hormone in rat cardiocytes.

Synthesis and activity of the enzymatic equivalent of the sodium pump, Na,K-ATPase, are regulated by thyroid hormone in responsive tissues. The purpose of this study was to determine whether triiodothyronine (T3) regulates the level of the messenger RNA (mRNA) coding for Na,K-ATPase alpha- and beta-subunits in the heart. The expression of Na,K-ATPase mRNAs in in vitro myocardial cells was directly assayed by Northern and slot blot hybridization using Na,K-ATPase alpha- and beta-isoform-specific cDNA probes. Exposure of cultured neonatal rat cardiocytes to 10(-8) M T3 resulted in 1) threefold to fourfold increase in alpha 1- and beta 1-mRNA accumulation, with a maximum elevation at 48 hours, 2) sevenfold increase in alpha 2-mRNA accumulation with a peak elevation at 72 hours, and 3) transient threefold increase in alpha 3-mRNA within the first 24 hours followed by a deinduction thereafter. The increase in alpha 1-mRNA accumulation by T3 occurred over the physiological T3 concentration range with an EC50 of 5 x 10(-10) M. This was associated with a twofold increase in alpha 1-subunit protein accumulation and an increase in Na,K-ATPase transport activity. The half-life of alpha 1-mRNA analyzed by actinomycin D chase was less than 3 hours and was not affected by T3. Transfection experiments with the luciferase reporter gene revealed that thyroid hormone response sequences are located within the 5'-flanking regions of each alpha-isoform gene.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Ouabain as an amplifier of mineralocorticoid-induced hypertension.

Ouabain has recently been reported to be an endogenous Na, K-ATPase inhibitor. To evaluate whether it exerts hypertensive action itself or amplifies the hypertensive action of small doses of mineralocorticoids, 5 mg deoxycorticosterone acetate (DOCA), 1 mg ouabain, or a combination of both were injected into mononephrectomized rats weekly for 6 weeks, and changes in blood pressure were evaluated. The blood pressures of control, DOCA-treated, ouabain-treated, and the combination treatment group at the sixth week were 138 +/- 3 (SE), 160 +/- 6, 144 +/- 6, and 201 +/- 14 mmHg, respectively. The blood pressure of rats given DOCA or ouabain alone was not significantly different from that of controls. In contrast, the blood pressure of rats given the combination of DOCA and ouabain was significantly higher than that of control rats and those given DOCA or ouabain separately. Cardionephromegaly and histopathological changes found in rats given the combination of DOCA and ouabain were consistent with the effects of an elevation of blood pressure. Further evaluation revealed that the amplification effect of ouabain on the hypertensive action of DOCA was dose dependent, with the minimum dose that caused the amplification effect being 0.25 mg/week. These results indicate that ouabain, although devoid of hypertensive action itself, amplifies the hypertensive action of small doses of DOCA and can cause a hypertensive state similar to that induced by larger doses of DOCA. It is inferred that the amplification effect of ouabain on mineralocorticoids is important in the genesis of hypertension.

Animals↗
PubMed1992

Solitary eosinophilic granuloma in the frontal lobe: case report.

A rare case of a solitary eosinophilic granuloma in the brain is reported. The mass, located in the right frontal lobe, mimicked a glioma not only grossly, but also by neuroimaging. The lesion was confirmed to be an eosinophilic granuloma by electron microscopy and immunohistochemical staining for S-100 protein and HLA-DR.

Biomarkers↗
PubMed1992

Non-cholinergic mechanisms underlying the acute lethal effects of P = S type organophosphorus insecticides in rats.

Intravenous administration of the lethal dose of diazinon or fenthion, P = S type organophosphates, to urethan anesthetized rats induced bradycardia and transient apnea followed by a decline of blood pressure, and death. We investigated the mechanisms of the lethal action of these organophosphates in rats through measurements of blood pressure, heart rate, and respiratory pattern. We compared their cardiorespiratory effects in the five different conditions under anesthesia; 1) normal (without treatment), 2) artificially ventilated, 3) vagotomized, 4) atropinized, 5) pithed, vagotomized and atropinized. It was found that the administration of 200 mg/kg of fenthion and 100 mg/kg of diazinon, caused sudden bradycardia, transient apnea and gradual decline of blood pressure in the anesthetized normal rat, and the rat died. The rats in other conditions also died except the artificially ventilated rats, in which 400 mg/kg of fenthion was administered to cause hypotension and subsequent death. Hypotension was observed consistently even after the cardiac effect such as bradycardia was eliminated by atropine treatment. In the pithed rats which were further vagotomized and atropinized, these organophosphates also caused hypotension. These results may indicate that hypotension is the main cause of death which resulted from intravenous administration of the P = S types. Hypotension may be caused by peripheral cardiovascular effect of the P = S types, which is unrelated to cholinergic mechanisms.

Animals↗
PubMed1992

Carcinogenicity examination of 1-nitropyrene oxides and related chemicals: lack of their tumorigenic effects in a newborn mice assay.

Carcinogenicity of 1-nitropyrene (NP) oxides (1-NP 4, 5-oxide and 1-NP 9, 10-oxide) and related chemicals (1-NP and 1-nitro-6-hydroxypyrene) was examined in the newborn mouse model by i.p. administration at 1, 8, 15 days after birth (each chemical was given at a total dose of 700 nmol per mouse). Low incidences of hepatocellular neoplasms were recognized in male mice exposed to either of these chemicals. However, the incidences were not significantly different from those of animals given solvent alone or of non-treatment. Lymphoma was infrequently seen in female mice given some of tested chemicals. The incidences were also not significantly different from those of mice with the solvent alone or of the controls. The results suggest that although these aromatic hydrocarbons exert genotoxicity or mutagenicity, they may not be potent carcinogens, or the assay with use of newborn mice may be insufficient to monitor carcinogenicity of such chemicals.

Adenoma↗
PubMed1992

Study on the dye leakage response of nasal mucosa following topical, capsaicin challenge in guinea pigs.

We examined the serial changes of intravenously applied dye leakage and preliminary examined histamine release into nasal lavage fluid after topical stimulation with capsaicin in guinea pigs. A significant increase in the dye leakage response was detected for 30-40 min, with the maximum response occurring between 5 and 10 min after topical capsaicin stimulation. The dye leakage response to nasal capsaicin challenge was abolished by pretreatment with topical lidocaine, general substance P analogue, topical or general high dosage capsaicin. The dye leakage response to topical capsaicin challenge was significantly reduced following pretreatment with antihistamine, diphenhydramine or atropine sulfate, although it was not affected by pretreatment with an anti-leukotriene, FPL 55712. Topical methacholine challenge did not induce a dye leakage response. An increase in the concentration of histamine in the nasal lavage fluid was noted at 5 min after topical capsaicin challenge. The concentrations of released histamine tended to be positively correlated with those of leaked dye in the nasal lavage fluids. The histamine release induced by topical stimulation with capsaicin tended to be reduced following general and topical pretreatments with high dosage of capsaicin, and was almost completely abolished following atropine pretreatment. From this study it was concluded that nasal capsaicin stimulation can reflexively induce an intravenously applied dye leakage into the nasal cavity, and that C-fiber related cholinergic nerve reflex and histamine release might, at least partially, be related to this response.

Administration, Intranasal↗
PubMed1992

[Toxicology in legal medicine].

The purpose of toxicology in legal medicine is to determine the presence of chemicals effecting the human body in biological samples and to interpret the concentrations of chemicals. Analytical methods and medico-legal interpretations of the results of poisoning cases were discussed. 1. "Yusho," PCB poisoning "Yusho" was determined to be PCB poisoning by the detection of PCB in Rice-oil used by a "Yusho" family. My toxicological works were based on the study of "Yusho," which taught me the importance of the collaboration between faculties, the moral of the co-worker, and the PCB contamination in the laboratory. 2. Drugs In order to interpret the concentration of bromvalerylurea in blood, a very sensitive method was developed using a Florisil mini-column for cleaning up, and ECD-GC for analysis. GC/MS is used to determine the concentrations of other drugs in biological samples as well. 3. Pesticides In the first case of fatal ethyl parathion poisoning, only ethyl parathion in the stomach contents was analyzed by ECD-GC, and the cause of death was determined to be ethyl parathion poisoning. In the second case, parathion in the blood, brain, and stomach contents was analyzed. Both cases, however, were not reported in detail in the journal. Joint study on pesticides with the Division of Emergency Medicine is carrying on now. 4. Thinner Male rats were exposed to toluene vapor in pure oxygen, air, and 10%-O2 air. Anesthetic death from thinner vapor was confirmed. It seems that inhalation of toluene in a hypoxic atmosphere, such as from a plastic bag, is very dangerous.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[DNA typing and analysis of the D1S8 (MS 32) allele in the Japanese population by the minisatellite variant repeat (MVR) mapping by polymerase chain reaction (PCR) assay].

Minisatellite variant repeat (MVR) mapping using the polymerase chain reaction (PCR) of the D1S8 (MS32) locus from total genomic DNA and size separated alleles in the Japanese population was performed. DNA was extracted from blood in healthy non-related Japanese individuals. The digital data obtained were computer analysed, and from this single assay all unrelated individuals tested could be unambiguously distinguished. The average difference in diploid codes between unrelated individuals was 36 exclusions over the first 60 repeat unit positions. The mean proportions of a-, t-, and 0-type repeat units were 73.5%, 24.5% and 2.1%, respectively. MVR-PCR gives digital profiles which show extreme levels of individual variation and should prove very useful for personal identification. The advantages and further applications of MVR-PCR are also discussed.

Alleles↗
PubMed1992

[A new method for the determination of xanthine oxidase activity by high-performance liquid chromatography with electrochemical detection].

A non-radiochemically sensitive method for the determination of xanthine oxidase (XO, EC 1.1. 3.22) activity is devised. We have enabled to detect the low activity of XO in human serum or peripheral lymphocyte lysates by the pretreatment of samples with activated charcoal, and by the employment of a sensitive high-performance liquid chromatography with electrochemical detection. This method was shown to be reliable and reproducible, and allowed us to evaluate XO activity in various clinical samples. XO activity in serum, but not in peripheral lymphocytes reflected the degree of liver damage. No relationship was found between serum XO activity and serum uric acid. No XO activity was detected in sera from patients with hereditary xanthinuria. These results suggested this method to be quite useful for rapid diagnosis of the patients with abnormal purine metabolism, especially in that with hereditary xanthinuria.

Adult↗
PubMed1992

[Effects of anti-PAF agents on nasal response after allergen challenge in guinea pigs].

We previously reported that Platelet-activating factor (PAF) activities were detected in nasal lavage fluids from patients with allergic rhinitis and in ovalbumin (OA) sensitized guinea pigs after topical allergen challenge. In guinea pigs, a topical application of PAF produced an increase in nasal vascular permeability which was inhibited by a PAF-antagonist (CV3988). To define the role of PAF in allergic rhinitis, we examined the effects of anti-PAF agents (WEB2086) and anti-allergic agents (Azelastine) on nasal airway resistance (NAR) and nasal symptoms in actively sensitized guinea pigs. Guinea pigs (200-300g) were sensitized by intraperitoneal injection of OA (10 micrograms/kg) and alum (5mg/kg) three times at two week intervals and repeated inhalation of OA (1mg/min., for 3 minutes) everyday for four weeks. The NAR was measured serially for 6 hours by an apparatus using the oscillation method. NAR change was expressed as a percent ratio to the pre-challenge value. Nasal symptoms were evaluated by counting the number of sneezing discharges and scratching movements for 30 minutes. The anti-PAF agent or Azelastine were administered orally at 2-3 hours before the topical allergen challenge. We noted a biphasic increase in NAR after allergen challenge. The increase in NAR during early phase was not affected but that during late phase was significantly inhibited by the anti-PAF agent and Azelastine. The nasal symptoms were inhibited by WEB2086 and Azelastine. Our results suggest that PAF activities might play an important role in late phase NAR increase following allergen challenge.

Airway Resistance↗