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M Tomizawa

Publications and source records attributed to M Tomizawa.

At least 55 records · Page 3Linked to original sources
PubMed1996

Novel neonicotinoid-agarose affinity column for Drosophila and Musca nicotinic acetylcholine receptors.

Neonicotinoids such as the insecticide imidacloprid (IMI) act as agonists at the insect nicotinic acetylcholine receptor (nAChR). Head membranes of Drosophila melanogaster and Musca domestica have a single high-affinity binding site for [3H]IMI with KD values of 1-2 nM and Bmax values of 560-850 fmol/mg of protein. Locusta and Periplaneta nAChRs isolated with an alpha-bungarotoxin (alpha-BGT)-agarose affinity column are known to be alpha-subunit homooligomers. This study uses 1-[N-(6-chloro-3-pyridylmethyl)-N-ethyl]amino-1-amino-2-nitroethene++ + (which inhibits [3H]IMI binding to Drosophila and Musca head membranes at 2-3 nM) to develop a neonicotinoid-agarose affinity column. The procedure-introduction of Triton-solubilized Drosophila or Musca head membranes into this neonicotinoid-based column, elution with IMI, and analysis by lithium dodecyl sulfate-polyacrylamicle gel electrophoresis-gives only three proteins (69, 66, and 61 kDa) tentatively assigned as putative subunits of the nAChR; the same three proteins are obtained with Musca using the alpha-BGT-agarose affinity column. Photoaffinity labeling of the Drosophila and Musca putative subunits from the neonicotinoid column with 125I-alpha-BGT-4-azidosalicylic acid gives a labeled derivative of 66-69 kDa. The yield is 2-5 micrograms of receptor protein from 1 g of Drosophila or Musca heads. Neonicotinoid affinity chromatography to isolate native Drosophila and Musca receptors will facilitate studies on the structure and function of insect nAChRs.

Animals↗
PubMed1995

Neuropathy target esterase of hen brain: active site reactions with 2-[octyl-3H]octyl-4H-1,3,2-benzodioxaphosphorin 2-oxide and 2-octyl-4H-1,3,2-[aryl-3H]benzodioxaphosphorin 2-oxide.

2-Octyl-4H-1,3,2-benzodioxaphosphorin 2-oxide (octyl-BDPO) is one of the most potent inhibitors known for neuropathy target esterase (NTE) of hen brain with 50% inhibition at 0.2 nM. Two NTE-like proteins, i.e., resistant to paraoxon and sensitive to mipafox, of approximately 155 and approximately 119 kDa (designated NTE-155 and NTE-119, respectively) are labeled by [octyl-3H]octyl-BDPO and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Labeling with [aryl-3H]octyl-BDPO is only approximately 15% of that with [octyl-3H]octyl-BDPO, indicating that the majority of the phosphorylated NTE undergoes aging with only a small proportion of nonaged target or intramolecular group transfer ("alkylation"). NTE-155 and NTE-119 have the same kinetic constants and maximal number of phosphorylation sites, equivalent for each of them to 26 fmol/mg of protein and totaling at least 0.44-1.2 micrograms of NTE protein/g of brain. Structure-activity investigations involving 17 combinations of organophosphorus (OP) compounds of varied chemical type, stereochemistry, and concentration establish an excellent correlation (r = 0.95) between inhibition of NTE activity and protein labeling and thereby the toxicological relevance of these assays, which equally implicate NTE-155 and NTE-119 (probably an autolysis product of NTE-155) as target in OP-induced delayed neuropathy. [octyl-3H]-Octyl-BDPO is an improved probe for NTE in terms of its potency, reactivity, selectivity, and the formation of 3H-labeled NTE with a stable phosphorus-carbon bond.

Animals↗
PubMed1995

Growth patterns and interstitial invasion of small hepatocellular carcinoma.

Twenty-five cases of small hepatocellular carcinoma (HCC; diameter < or = 30 mm) were evaluated for overall morphologic features and growth patterns. The tumors often showed a well-differentiated, normotrabecular histologic pattern and insidious interstitial invasion, which resembled benign hepatocytes scattered in connective tissues. As the tumor grew, a less-differentiated tumor area became predominant. Portal tracts included in small HCC nodules were quantitatively assessed, revealing that they progressively reduced in number with tumor growth. The tumor margin was often reported to be unclear. The present results indicate that the histologic grade of tumor differentiation, capsular formation, existence of liver cirrhosis and patterns of interstitial invasion are important factors for determining the nature of the margin. The score of argyrophilic nuclear organizer regions (AgNOR) was examined in 5 cases showing typical interstitial invasion with the insidious type. In each case, the AgNOR score of the invading tumor cells was lower than that of tumor cells within the HCC nodules, but higher than benign hepatocytes in cirrhotic parenchyma. It clarified that the growth activity of well-differentiated HCC was rather suppressed upon their interstitial invasion.

Carcinoma, Hepatocellular↗
PubMed1995

[A comparative study of tazobactam/piperacillin and piperacillin in bacterial pneumonia].

The efficacy, safety and usefulness of tazobactam/piperacillin (TAZ/PIPC), in bacterial pneumonia and lung abscess were determined with PIPC as the control in a multi-institutional comparative study a penicillin antibiotic for injection prepared by combining a newly developed beta-lactamase inhibitor, tazobactam (TAZ), with a broad spectrum penicillin antibiotic, piperacillin (PIPC), at a ratio of 1:4. TAZ/PIPC was intravenously injected at a dose of 2.5 g (titer) twice a day, and PIPC at a dose of 2.0 g (titer) twice a day as a rule for 14 days. The following results were obtained: 1. The efficacy rates for bacterial pneumonia and lung abscess were 94% (80/85) in TAZ/PIPC group and 89% (70/79) in PIPC group, showing no significant difference between the two groups. 2. In a comparison of degrees of improvement in clinical symptoms, signs and laboratory findings, there were no significant differences between the two groups except for results on thoracic rales after three days of administration. 3. As for bacteriological effects, the elimination rates of causative organisms were 98% (40/41) in the TAZ/PIPC group and 80% (28/35) in the PIPC group. Thus, the TAZ/PIPC group was significantly superior to the PIPC group. The TAZ/PIPC group showed significantly better eradication of bacteria as well. Bacteria considered to be pyogenic were detected in 80 patients (43 administered TAZ/PIPC and 37 administered PIPC), but beta-lactamase production was confirmed in only 11 patients of each group. There were no significant differences in bacteriological effects among these patients. Minimum inhibitory concentrations of TAZ/PIPC against beta-lactamase producing organisms were distinctly superior to those of PIPC. 4. Side effects occurred in 10% (10/96) of the TAZ/PIPC group and 7% (7/95) of the PIPC group. Abnormal clinical laboratory test values were observed in 22% (20/92) of the TAZ/PIPC group and 18% (17/93) of the PIPC group. Thus, there were no significant differences between the two administration groups. 5. The usefulness rate in the TAZ/PIPC group was 87% (75/86) and it was 85% (67/79) in the PIPC group, showing no significant difference between them. The results suggest that TAZ/PIPC administered at a dose of 2.5 g (titer) twice a day is more useful than PIPC administered at a dose of 2.0 g (titer) twice a day in the treatment of bacterial pneumonia.

Adult↗
PubMed1994

Effect of sugars-addition on the survival of vitrified bovine blastocysts produced in vitro.

We investigated the effect of addition of sugars to a vitrification solution on the survival rate of bovine blastocysts produced in vitro. In vitro-matured (IVM) and in vitro-fertilized (IVF) bovine Day-6 to Day-8 bovine blastocysts were classified into 3 developmental stages: early blastocysts, blastocysts and expanded blastocysts. The blastocysts were cryopreserved in 1 of 3 vitrification solutions: 1) 25% glycerol25% ethylene glycol (GE); 2) 20% glycerol20% ethylene glycol3/4 M sucrose (GES); and 3) 20% glycerol20% ethylene glycol3/8 M sucrose3/8 M dextrose (GESD). The basic solution was Dulbecco's PBS supplemented with 20% of fetal calf serum. Embryos were exposed to each vitrification solution in 3 steps, and after loading into 0.25-ml straws, were plunged into liquid nitrogen. After warming in water bath at 20 degrees C, cryoprotectants were diluted in 1/2 M and 1/4 M sucrose each for 5 min. Equilibration and dilution procedure except warming were conducted at room temperature (23 to 27 degrees C). After dilution, the embryos were cultured in Ham's F10 medium0.1 mM beta-mercaptoethanol20% fetal calf serum. Survival rates of embryos at 48 h of incubation of each of the 3 developmental stages (early blastocysts, blastocysts and expanded blastocysts) exposed to the 3 types of the vitrification solutions (GE, GES and GESD) were 23.5, 33.3, 65.8% (early blastocysts, blastocysts and expanded blastocysts respectively) in GE, 55.6, 71.9, 90.5% in GES and 84.6, 83.3, 95.8% in GESD respectively. These results indicate that a mixture of 25% glycerol25% ethylene glycol is not suitable for vitrification of early bovine blastocysts; however, addition of sugars to the solution significantly (P<0.01) improved the survival rate of the vitrified blastocysts, independently of their stage of development.

Journal Article↗
PubMed1994

Compound odontomes associated with impacted maxillary primary central incisors: report of two cases.

Odontomes associated with primary teeth are rare. This report describes two cases of compound odontome associated with impacted maxillary primary central incisors in patients aged 1 year 8 months and 1 year 2 months, the latter being the youngest to have been reported with the condition. The odontomes were removed under local anaesthesia. Histological examination revealed immature dental tissues in both cases, but no evidence of root formation. Case 1 revealed 'ghost cells' within the enamel epithelium. The impacted incisors erupted following removal of the odontomes; in Case 2 the crown had an unusual ridge on its labial surface, extending from the gingival margin to a few millimetres from the incisal edge.

Female↗
PubMed1990

[A clinical observation of epithelial pearls in newborn babies. 1. Appearances and continuous changes].

The purpose of this study was to learn about the appearances and continuous changes of epithelial pearls. The study group comprised 517 normal newborn babies (261 males and 256 females) aged from 24 hours of birth to 22 days. Furthermore, we made the follow-up survey on the continuous changes in 21 newborn babies at the Niigata University Medical Hospital. The following results were obtained by analyses of the examination of the oral cavity in newborn babies during the period from December 1987 to December 1988. 1) Yellow-white in colour, pinhead shaped, 1-3 mm diameter in size, elevated firm nodules were seen in the alveolar ridge mucosa of the maxilla, mandible and/or palate. The average number of epithelial pearls was 1-3. 2) The number of newborn babies who had epithelial pearls was 226 (109 males and 117 females) out of 517 (43.7%). There was no predominant sex preference. 3) The most common location was the maxillary alveolar mucosa (309, 72.5%) followed by the median palatine raphe (97, 22.8%) and mandibular alveolar mucosa (20, 4.7%). 4) In this study, the relationship between the environmental factors of newborn babies in the prenatal and postnatal periods (mother's age, the course of the pregnancy, trouble at birth, the period of pregnancy, baby weight at birth etc.) and the rate of appearances of the epithelial pearls was examined. These factors showed no significant relationships. 5) Based on the findings of the clinical investigation of epithelial pearls during neonatal period, some cases were found and involved thickening and/or thinning in changes in the quantity and number.

Dental Enamel↗
PubMed1990

[Clinico-statistical observation of the dental surgery in the pedodontics clinic of Niigata University Dental Hospital during the period from 1979 to 1989].

Clinico-statistical observation was performed on the dental surgery in the Pedodontic Clinic of Niigata University Dental Hospital during the period from August 1979 to September 1989. 1. The number of surgical operations amounted to 656 cases (males 384 and female 272) and the highest age incidence was in the 6-8 year old range. 2. The incidence of the impacted teeth (62.8%) and the abnormality of the frenum (22.8%) occupied over 85% of all the cases. 3. Based on sex, the impacted supernumerary teeth and the abnormality of the buccal frenum, odotoma were more frequent in males, while the abnormality of the upper frenum and the mucous cysts were more frequent in females. 4. About 40% of the operative patients accepted were introduced from other medical institutions. 5. Regarding the methods of surgery, the impacted permanent teeth were frequent revealed by surgical exposure, while the diseases of salivary glands were revealed by extirpation. The benign tumors were removed by extirpation, the diseases of soft tissues by excision, cysts in the jaws were all surgically removed by marsupialization. 6. In regard to the age at the time of the operation, the abnormal frenum were often seen under 4 years of age but large increases were found in the impacted teeth from 4 to 8 years of age. The diseases of salivary glands and of soft tissues were seen more frequently under 10 years of age, and cysts in the jaws were noted after 7 years of age. 7. Children undergoing surgery who suffered from general diseases amounted to 31 cases and were found most commonly in cases of nervous mental diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1990

[An investigation into the actual condition of children with blood diseases in the pedodontic clinic of Niigata University Dental Hospital].

Children with blood diseases do not infrequently visit the dental clinics. Therefore, it is important to recognize the actual condition of blood diseases in association with the oral treatment of patients. During the period from Sept. 1979 to June 1989, 68 patients who had blood diseases visited the Pedodontic Clinic of Niigata University Dental Hospital. This report is the investigation of the dental situation of these patients. The result were as follows: 1. The ratio of patients with blood diseases in our clinic was 0.7%. The patients with leukemia were most frequent. 2. Most of the first visit-patients with blood diseases were children aged 6, while the general patients group was younger. The ages of first visit-patients corresponded to the most frequent ages of primary diseases. 3. The majority of their chief complaints were "the treatment of decayed teeth for caries". Others were "the extraction of loose teeth for exchange" or "the diseases of oral soft tissues". 4. The patients visited our clinic from all over Niigata prefecture, some of which visited from a great distance and were introduced by Niigata University Medical Hospital. 5. As to the treatment of decayed teeth for caries, the patients with hemophilia had a large number of treated teeth as compared with the other diseases. In case of leukemia, anaphylactoid purpura and idiopathic thrombocytopenic purpura (ITP), the outpatients generally tend to be subject to more severe caries than the inpatients in Niigata University Medical Hospital. 6. The percentage of recall of patients with blood disease was lower than that of general children at the rate of about 20%.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Disorders↗
PubMed1990

[Clinical evaluation of BMY-28100 for bacterial pneumonia in comparison with cefaclor in a double-blind study].

The efficacy, safety and usefulness of BMY-28100 for the treatment of bacterial pneumonia were compared with those of cefaclor (hereinafter referred to as CCL) in a double-blind study. The daily dosages were 750 mg for BMY-28100 and 1,500 mg for CCL, divided into 3 administrations daily. These drugs were administered orally for at least 14 days. A total of 172 cases were enrolled in this study. Of these, cases which deviated from the protocols were excluded from evaluations. Thus, clinical efficacy was evaluated in 124 cases, adverse reactions were evaluated in 160 cases, and abnormal laboratory test values were evaluated in 146 cases. The following results were obtained. 1. Efficacy rates ("good" or better responses) in bacterial pneumonia cases as evaluated by the subcommittee were 81.7% (49/60) in the BMY-28100 group and 89.1% (41/46) in the CCL group, thus no significant difference was found between the 2 groups. 2. Efficacy rates ("good" or better responses), as evaluated by investigators, in the same bacterial pneumonia cases which were subjected to the evaluation by the subcommittee were 83.3% (50/60) in the BMY-28100 group and 88.9% (40/45) in the CCL group, thus no significant difference between the 2 groups was found also. 3. Bacteriological response rates in bacterial pneumonia cases were 86.2% (25/29) in the BMY-28100 group and 85.7% (18/21) in the CCL group with no significant difference between the 2 groups. 4. Incidences of subjective/objective clinical adverse symptoms were 3.5% (3/85) in the BMY-28100 group and 1.3% (1/75) in the CCL group, and no significant difference was observed between the 2 groups. No significant difference was also found between the 2 groups in incidences of abnormal laboratory test values, as abnormalities were found in 21.1% (16/76) of the cases in the BMY-28100 group and 25.7% (18/70) in the CCL group. 5. As for overall usefulness of the drug in bacterial pneumonia cases, utility rates ("useful" or better evaluations) as evaluated by the subcommittee were 83.6% (46/55) in the BMY-28100 group and 90.5% (38/42) in the CCL group, and the rates as evaluated by investigators in cases judged as evaluable by the subcommittee were 78.3% (47/60) and 82.2% (37/45), respectively. There were no significant differences between the 2 groups. The utility rates as evaluated by investigators in cases in which diseases were diagnosed as bacterial pneumonia or lung abscess by investigators were 78.3% (47/60) in the BMY-28100 group and 82.2% (37/45) in the CCL group.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1989

[Double-blind comparative study of roxithromycin (RU 28965) and midecamycin acetate (MOM) in the treatment of pneumonia].

The clinical efficacy and safety of Roxithromycin (RU) were compared with those of Midecamycin acetate (MOM) in patients with pneumonia in a double blind study. RU and MOM were administered orally for 14 days with daily doses of 300 mg (150 mg b.i.d.) and 600 mg (200 mg t.i.d.), respectively. The following results were obtained. 1. RU and MOM were administered to a total of 204 patients (RU: 101, MOM: 103). The clinical efficacy was judged in 150 patients (RU: 70, MOM: 80), with 54 of the patients excluded from the total by the committee. 2. The clinical efficacy rates were 81.4% for RU and 70.0% for MOM on the basis of the committee's judgement. There was no significant difference between the two groups. In the evaluation of the clinical efficacy by the doctors in charge, the efficacy rates were 81.4% for RU and 67.5% for MOM, which constitutes a significant difference between the two groups (p less than 0.05). 3. No significant difference was found between the two drugs in bacteriological efficacy. 4. No significant differences were observed in either the incidence of side effects between RU (4.3%) and MOM (4.0%) or in abnormal changes in the laboratory findings. 5. Regarding the clinical usefulness judged by the committee, RU showed a significantly higher rate than MOM (79.2% vs. 67.9%). There was no significant difference in the judgement by the doctors in charge. From the above results, it was concluded that a daily dosage of 300 mg of RU was equal in usefulness to 600 mg daily of MOM in the treatment of mild to moderate pneumonia.

Adolescent↗
PubMed1989

[Clinical studies on 16 cases of odontoma in children].

16 cases of odontoma (male: 12, female: 4) in young patients from 1 year 2 months to 14 years of age at the Pedodontic Clinic of Niigata University Dental Hospital in a recent 9 year period were investigated clinically. As for the pathologic histology, 12 cases were of the compound type, 2 were of the complex type, 1 was of the intermediate type between compound and complex, and 1 was of ameloblastic fibro-odontoma type. 9 cases occurred in the maxilla, 7 cases occurred in the mandible. Most of the compound type were observed in the area of the maxillary incisors and cuspids, and the complex type cases were noted in the anterior part of the maxilla. In many cases, there were clinical symptoms such as retarded eruption. Some cases of odontoma in children were small in scale and showed a low degree of calcification. Therefore they showed a tendency not to be found out at radiography, and it is difficult to diagnose them as odontoma. By finding odontoma prematurely and removing it in time, the retarded eruption teeth were able to erupt spontaneously or to be guided to a normal position.

Child↗
PubMed1989

[Dental findings in a case of idiopathic hypoparathyroidism].

Idiopathic hypoparathyroidism is characterized by a deficiency of the parathyroid hormone, origin unknown, and causes a low serum calcium and a high serum inorganic phosphorus. This report concerns a clinical observation of a case of idiopathic hypoparathyroidism. This case was examined from the dental point of view. The findings were as follows: 1. The roentgenographic findings revealed that there was no demonstrable abnormality concerning bone age indicated between the ages of 5 and 6 years. 2. Severe dental caries were noted in the deciduous teeth and the permanent teeth. 3. Hypoplasia and hypocalcemia were recognized in most of the permanent teeth. 4. Large pulp chambers were observed in the deciduous teeth and the permanent teeth, and thickening of the lamina dura was observed in the permanent teeth. 5. The histological findings of the extracted deciduous teeth and the upper right first molar were such that: (1) there was hypoplasia and hypocalcemia in the dentin of deciduous teeth, and there were multiple resorptions in the cementum. (2) there was hypoplasia in the enamel of the upper right first molar. 6. Electron probe microanalysis of the upper left second molar revealed that the degree of mineralization and concentration of Ca, P and Mg in the dentin of the root showed a lower intensity than in the dentin of the normal one. 7. It was assumed from the dental point of view that this hypoparathyroid condition first appeared at about 11'months approximately 18'months of age.

Child, Preschool↗
PubMed1989

[Treatment of Riga-Fede's disease by resin-coverage of the incisal edges and seven cases of natal and neonatal teeth].

This report concerned 2 cases (1-month and 8-day-old boy and 5-month and 27-day-old boy) of Riga-Fede's disease. The cases were treated with photopolymerized resin coverage of the incisal edges. Generally, the treatment methods for Riga-Fede's disease are discing and extraction of the traumatized teeth. The photopolymerized resin coverage proved to help in the rapid healing of the ulcerations. This method is useful because it is easy and is able to avoid a false pulp exposure of the hypoplastic natal and neonatal teeth by discing. 7 cases of natal and neonatal teeth were encountered at the Pedodontic Clinic of Niigata University Dental Hospital during 8 years from September 1979 to August 1987. 1) 7 cases were 3 boys and 4 girls, aging from 21 days after birth to 3 months 19 days. 2) Only one baby had a low birth weight. 3) The natal teeth accounted for 6 cases and the neonatal teeth accounted for 1 case. All were lower central primary incisors (5 on the right side, 1 on the left side and 1 bilateral). There were no supernumerary teeth. 4) 5 cases were of hypoplastic teeth. 5) Riga-Fede's disease was recognized in 3 cases. 6) The prognosis was 1 case of shedding, 2 cases extracted and 4 cases remaining. 7) Mesial inclination of the neighboring teeth and narrowness of the extracted space wee observed in the cases where extraction was performed at an early age. 8) Microradiogram and undemineralized specimens of the extracted tooth revealed that the tooth was very thin and mineralization was so poor and there was almost no root formation.

Child, Preschool↗