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M Kiguchi

Publications and source records attributed to M Kiguchi.

14 recordsLinked to original sources
PubMed1993

[Studies on screening for hard-of-hearing children by questionnaire. 2. Comparison of response rates to individual questions in 1-year-6-month-old children with normal hearing and hearing loss using a health screening questionnaire].

We report the results of studies on responses to questions on hearing impairment, comparing 165 school children whose hearing was diagnosed as normal at the time of admission to primary school and 37 children with hearing loss attending facilities for children with this disability. These children had been covered by similar surveys as part of the health screening for 1-year-6-month-old infants conducted by municipal authorities. Significant differences between the two groups were noted in the response rates to all questions on hearing. Similar differences were noted in the responses to questions on family history of hearing impairment. There were no significant differences in the incidences of asphyxia and jaundice at birth. The most striking differences were noted in the response rates to questions 6, 7, 8, 10, 11, 16, and 18. Most useful and universally valid in this survey were questions 8, 10 and 18 in addition to the question on whether or not parents suspected infantile hearing loss.

Child, Preschool↗
PubMed1990

[Three-month oral subacute toxicity study of mofezolac (N-22) in rats].

A three-month oral subacute toxicity study of mofezolac (N-22), a non-steroidal anti-inflammatory agent, was performed using dose levels of 6, 20, 60 and 200 mg/kg in rats, and recovery was also assessed one month after withdrawal. 1. Toxic signs caused by N-22 administration, observed only in the 200 mg/kg group, were as follows: soiling around the mouth and/or nose, piloerection, anemia, diarrhea, emaciation and decreased spontaneous locomotor activity. Nine males and thirteen females in the 200 mg/kg group excreted bloody diarrhea and died of general exhaustion between weeks four and thirteen of study. 2. In the 200 mg/kg group, decrease in food consumption and suppression of body weight gain were noted in males from about week four and in females from about week six after initiation of administration, and increase in water consumption was noted in males from about week seven. 3. Urinary examination revealed a decline in urinary pH in males of the 20 mg/kg and above groups and elevation of urobilinogen levels in males of the 60 and 200 mg/kg groups. 4. Hematological examination showed decreases in erythrocyte count (RBC), hematocrit value (Ht) and hemoglobin concentration (Hb) and increase in reticulocyte rate in both sexes of the 200 mg/kg group and an increase in neutrophil rate in males of the 200 mg/kg group. 5. Biochemical examination demonstrated a decrease in chloride (Cl-) in males receiving the 20 mg/kg or above doses and a decrease in calcium (Ca++) in males of the 60 and 200 mg/kg groups. Moreover, there were decreases in cholinesterase (ChE) activity, total protein (TP) and albumin (Alb) values, as well as increases in blood urea nitrogen (BUN), uric acid (UA) and potassium (K+) in both sexes of the 200 mg/kg group, along with elevations in GOT and lactate dehydrogenase (LDH) activities in females of the 200 mg/kg group. 6. The absolute and/or relative organ weights for liver, kidneys, spleen and adrenals were increased in the 200 mg/kg group. 7. On pathological examination, perforating ulceration in the jejunum and ileum, turbid ascites, adhesion and inflammatory changes in capsules of the abdominal organs, splenomegaly, mesenteric lymph node hyperplasia and inflammatory changes in the thoracic cavity were observed in dead animals of the 200 mg/kg group. Similar pathological changes were observed in a few survival cases of the 200 mg/kg group. 8. After a one month recovery period, the above-mentioned changes had mostly recovered, indicating that they were reversible.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1990

[Three-month subacute oral toxicity study of mofezolac (N-22) in dogs].

Mofezolac (N-22) is a new developed analgesic and anti-inflammatory agent. A subacute oral toxicity test of N-22 was carried out at dose-levels of 0, 2, 6 and 20 mg/kg/day using male and female beagle dogs. Treatment for 3 months was followed by 1 month recovery period except in the case of both sexes receiving 20 mg/kg/day. The results obtained from the present study were as follows. 1. Observation of general conditions revealed vomiting, sporadic bloody feces, anemia, recumbency and hyposthenia in both sexes receiving 20 mg/kg/day. Anemia or erosion of tongue was observed in each female receiving 6 mg/kg/day. 2. Respectively 3 dogs of both sexes receiving 20 mg/kg/day died during dosing period. In these animals, perforating ulcers were observed in the pars pylorica ventriculi or duodenum, and loss of blood, peritonitis and aggravation of general exhaustion were considered as causes of death. 3. Body weight tended to decrease in both sexes receiving 20 mg/kg/day, and food and water consumption levels decreased in males receiving 2 mg/kg/day or above and females receiving 2 mg/kg/day. 4. Urinalysis demonstrated an increasing tendency for specific gravity of urine and a decreasing tendency for urine volume in males receiving 2 mg/kg/day or above. 5. Hematological examination showed decreases in red blood cell count and Hb concentration in males receiving 2 mg/kg/day or above, and in Ht values in males receiving 6 mg/kg/day or above. 6. Serum biochemical examination revealed decreases in total protein and albumin in both sexes receiving 20 mg/kg/day. 7. There were no remarkable changes in hepatic and renal function, ophthalmological findings or electrocardiogram. 8. In the organ weights, significant decrease in thymus weights was observed in the dead animals receiving 20 mg/kg/day. 9. Pathologically, the dead animals receiving 20 mg/kg/day were found to exhibit peritonitis with perforating ulcers in the pars pylorica ventriculi or duodenum. In the surviving animals of this group, scar ulcers in the pars pylorica ventriculi and small intestine were evident on necropsy, and histopathology revealed neutrophils infiltration and thrombosis in blood vessels in the thickened submucosal stomach tissues. Moreover, localized hepatocyte necrosis and intrasinusoidal cellular infiltration in liver, as well as interstitial cellular infiltration, degeneration and dilatation of the renal tubules in the kidney were observed. In females receiving 6 mg/kg/day, the changes in kidney were similar to those in surviving animals receiving 20 mg/kg/day, and male of the group showed atrophy of thymus.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1987

Comparative study of colorimetric method using diazotization reaction and high-performance liquid chromatographic method in determination of para-aminohippuric acid.

In this study, colorimetric method and high-performance liquid chromatographic (HPLC) method were improved and established, respectively, in order to minimize analytical errors in determination of para-aminohippuric acid (PAH) in rat urine and plasma. In terms of the colorimetric method, an operative step following addition of Tsuda reagent was modified as follows: after the addition of Tsuda reagent, reaction mixture was kept at 40 degrees C for 70 min before spectrophotometry. Linearities were observed both in the higher range of 0 and 2.5 to 12.5 micrograms and in the lower range of 0 and 100 to 1,000 ng per test tube, and its practical detection limit was 100 ng per test tube. In terms of HPLC method, using a reversed-phase column (Nucleosil 5 C18), PAH was separated by a mobile phase of acetonitrile/50 mM KH2PO4 (pH 2.8) = 9/95. Linearities were observed in the higher range of 0 and 10 ng to 2 micrograms and in the lower range of 0 and 1 to 10 ng per injection, and its practical detection limit was 1 ng per injection. These results denote that the above two methods are applicable to routine PAH determination. In addition, our HPLC method is considered to be applicable to microassay of PAH, because its sensitivity is more sensitive and minimization of volume system is more easily achieved as compared with the colorimetric method.

Aminohippuric Acids↗
PubMed1985

[Study on toxicity of halopredone acetate. (II). Subacute toxicity study in rats].

Halopredone acetate (THS-201), a synthetic corticosteroid, is expected to be used clinically for intra-articular injection because of its long-lasting activity in the synovial bursa. Subacute toxicity study was carried out on THS-201 by using Jcl: Wistar rats. THS-201 was subcutaneously administered to the rat in doses of 0.1, 0.5, 2.5 and 12.5 mg/kg/day, with the periods for administration and recovery being 3 and 2 months, respectively. Methylprednisolone acetate (MPA) was used for the positive control in dose of 0.5 mg/kg/day. In the group of THS-201 12.5 mg/kg, the below findings were observed: thinning of lumbar hair, swelling of injection site, suppression in body weight gain and decrease of food consumption. The lesions to lymphatic system were indicated by the examinations of peripheral blood, autopsy and histopathology. Slight changes in erythrocytic and biochemical values were seen, and foreign body granuloma was observed in injected subcutis. These findings, exception for lesion of injection site, were almost recovered after the 2 month-recovery period. In the group of THS-201 2.5 mg/kg, some of the changes were noted slightly. In the groups of THS-201 0.5 and 0.1 mg/kg, any toxic changes attributable to THS-201 were not observed. On the other hand, in the group of MPA 0.5 mg/kg, similar findings noted in THS-201 12.5 mg/kg group were observed, but these changes were recovered almost completely at the end of the 2 month-recovery period. It was concluded that the non-toxic dose and the defined toxic dose of THS-201 in this study were 0.5 and 2.5 mg/kg/day, respectively.

Animals↗
PubMed1984

[Chronic toxicity study of AC-1370 sodium, an antibiotics, intravenously administered in rats].

A study on chronic toxicity of AC-1370 sodium (AC) in addition to recovery from its toxicity, was carried out using the rat. AC was administered to the rat through the tail vein in doses of 30, 100, 300 and 1000 mg/kg body weight/day, with the periods for administration and recovery being 26 and 13 weeks, respectively. The results obtained from the present study were as follows. In each group, neither death case nor fatal damage was observed throughout the whole process. In the group of 1000 mg/kg, the below findings were observed in one or both sexes: suppression in increase of body weight, increases in drunk amount of water, urinary volume and urinary excretions of electrolytes, degeneration in renal tubules and several correlated changes, tendency of anemia, changes in serum biochemical tests, and changes in each organ weight. In the group of 300 mg/kg, the above findings were observed slightly in comparison to the group of 1000 mg/kg. In the groups of 100 and 30 mg/kg, any changes suggesting the damages were not observed. In the recovery test, the group of 1000 mg/kg was found to be incompletely restored from the damages, with the partially residual damages being shown. In contrast, the group of 300 mg/kg showed to be almost restored from the damages. These results denotes that the maximal non-toxic dose of AC in this study is 100 mg/kg/day in long-term administration.

Animals↗
PubMed1983

[Chronic toxicity study of ranitidine hydrochloride orally administered in rats].

Chronic toxicity of ranitidine hydrochloride, a new histamine H2-receptor antagonist, was studied using Sprague Dawley rats. Ranitidine was administered orally at dose levels of 30, 100, 300 and 1000 mg/kg/day for 26 or 53 weeks. In the 1000 mg/kg/day group, ten of 31 females died showing acute toxic signs. In the survived animals of this dose group, changes were observed, such as salivation, depression of body weight gain, increase in water consumption, increase in urinary Na and K excretion, increase in serum albumin content, increase in weights of the liver, kidneys and heart. Main histopathological findings were as follows: centrolobular or midzonal fat deposition in liver, increase in s-ER in hepatocytes, increase in foamy cells in lung and some slight degenerative changes occasionally seen in renal tubules. In the 300 mg/kg/day group, the changes similar to those in the 1000 mg/kg/day group were observed, however, the degree of these changes was more moderate. All of the above-mentioned findings were demonstrated to be reversible in recovery period for 8 weeks. In the 100 and 30 mg/kg/day groups, no remarkable changes were observed in both sexes. It was concluded that the maximum nontoxic dose of ranitidine hydrochloride was 100 mg/kg/day in male and female rats.

Administration, Oral↗
PubMedDate not supplied

Rat two-generation reproductive toxicity study of bisphenol A.

This study was conducted to determine the low-dose effects of bisphenol A (BPA) in a rat two-generation reproduction study. Groups of 25 male and 25 female Crj: CD (SD) IGS rats were given BPA at 0.2, 2, 20, or 200 microg/kg/day by gastric intubation throughout the study beginning at the onset of a 10- and 2-week premating period, in F0 males and females, respectively, and continuing through the mating, gestation, and lactation periods, for two generations. There were adult (F0, F1, F2) and postnatal day (PND) 22 (F1, F2) necropsies: the oldest F2 males and females being killed at postnatal weeks 7 and 14, respectively. No compound-related clinical signs or effects on body weight or food consumption were observed in any generation. There were no compound-related changes in surface righting reflex, negative geotaxis reflex, mid-air righting reflex, pinna detachment, incisor eruption, eye opening, testes descent, preputial separation, or vaginal opening in F1 and F2 generations, or behavior in the open field or water filled multiple T-maze in the F1 generation. No test compound-related changes in estrous cyclicity, copulation index, fertility index, number of implantations, gestation length, litter size, pup weight, pup sex ratio, pup viability, or other functional reproductive measures were noted in any generation. A few significant changes in the anogenital distance (AGD) per cube root of body weight ratio were found at 0.2 and 20 microg/kg in F1 males, at 2, 20, and 200 microg/kg in F1 females, and at 20 and 200 microg/kg in F2 females. However, the changes in the AGD were consistently small (within 5% of control values), and no continuous changes in the AGD or AGD/cube root of body weight ratio were detected. There were no compound-related changes in epididymal sperm counts or motility in F0 and F1 males. No compound-related necropsy findings or effects on organ weight including the reproductive organs were found in any generation. Histopathologic examinations revealed no evidence of compound-related changes in any organs including the reproductive organs of both sexes. The data indicate that oral doses of BPA of between 0.2 and 200 microg/kg over 2 generations did not cause significant compound-related changes in reproductive or developmental parameters in rats.

Administration, Oral↗
PubMedDate not supplied

Fabrication and observation of a standard sample for near-field optical microscopy.

We fabricated a standard sample for a near-field optical microscope using scanning probe lithography. The sample contains a wedged pattern, which allows the measurement of various sizes within one image. The optical resolution of our near-field optical microscope has been evaluated as 40 nm, which was obtained by measuring the narrowest separable gap width of the wedged pattern. Thus a standard sample containing the wedged pattern enables clear evaluation of the resolution.

Journal Article↗
PubMedDate not supplied

Effects of NMDA and MK-801 injected into the substantia nigra pars reticulata on jaw movements evoked by dopamine D1-/D2 receptor stimulation in the ventrolateral striatum: studies in freely moving rats.

The effects of NMDA and MK-801 injected into the substantia nigra pars reticulata on jaw movements evoked by dopamine D1/D2 receptor stimulation in the ventrolateral striatum were examined in freely moving rats, by using a magnet-sensing system combined with intracerebral drug microinjection technique. Bilateral injections of a mixture of SKF 82958 (5 microg) and quinpirole (10 microg), agonist at dopamine D1 and D2 receptors respectively, into the ventrolateral striatum elicited repetitive jaw movements. Bilateral injections of NMDA (0.01 and 0.05 microg/0.2 microl in each side) into the substantia nigra pars reticulata, which alone did not produce jaw movements, reduced the repetitive jaw movements evoked by the dopamine D1/D2 receptor agonist mixture in a dose-dependent manner. Injection of the non-competitive NMDA receptor antagonist, MK-801 (0.1 and 0.5 microg/0.2 microl in each side), into the substantia nigra pars reticulata, which alone did not produce jaw movements, prevented the dopaminergic jaw movements in a dose-dependent manner. Moreover, other behaviors such as grooming, rearing, yawning, vacuous chewing, and locomotor activity that occurred after injections of the dopamine receptor agonist mixture were not significantly altered by the bilateral injections of NMDA or MK-801 into the substantia nigra pars reticulata. Given our previous results showing that both agonist and antagonist of GABA(A) receptors injected into the substantia nigra pars reticulata inhibit the jaw movements elicited by dopamine D1/D2 receptor stimulation in the ventrolateral striatum, the present results suggest that there are complex functional interactions between NMDA and GABA(A) receptors within the substantia nigra pars reticulata that may be responsible for the common profiles in the effects of NMDA and GABA(A) receptor agents.

Animals↗