PubMed Health⌕ Search

Biomedical subjects

M Nakagomi

Publications and source records attributed to M Nakagomi.

At least 19 recordsLinked to original sources
PubMed2001

Effects of endocrine disrupting chemicals on the microtubule network in Chinese hamster V79 cells in culture and in Sertoli cells in rats.

The effects of ten endocrine disrupting chemicals, i.e., bisphenol A (BPA), p-nonylphenol (NP), p-octylphenol (OP), p-pentylphenol (PP), butyl benzyl phthalate (BBP), dicyclohexyl phthalate (DCHP), di-n-butyl phthalate (DBP), tetrabutyltin (TBT), tri-n-butyltin chloride (TBC), and di-n-butyltin dichloride (DBD), as well as 17 beta-estradiol (E(2)) as a positive control on the microtubule network in Chinese hamster V79 cells in culture were examined by the indirect immunofluorescence method using anti-beta-tubulin antibody. In the whole-animal system, the effects of BPA, NP, OP, BBP, DBD, and E(2) as well as vinblastine sulfate (VB) as a positive control on microtubules in the cytoplasm of Sertoli cells in rats were examined by electron microscopy. In Chinese hamster V79 cells, TBC and DBD showed higher microtubule-disruptive activity than E(2), while other chemicals had less activity than E(2). The ranking for efficiency on microtubule disruption was (TBC falling dots DBD) > (E(2) = TBT) > (BPA = alkylphenols, NP and OP) >> (phthalate esters, BBP, DHP, and DBP). In rats as a whole-animal system, no disrupting effects on the microtubule network in the cytoplasm of Sertoli cells were observed under any environmental chemicals tested, whereas exposure to VB resulted in marked disruption of the microtubule network. The results of this study suggested that some endocrine disrupting chemicals have disrupting effects on the microtubule network in vitro, but no such effects in vivo.

Animals↗
PubMed2000

Quantitation of catechol estrogens and their N-acetylcysteine conjugates in urine of rats and hamsters.

A method for the analysis of N-acetylcysteine conjugates of catechol estrogens [catechol estrogen mercapturates (CE SRs)], which are likely to be urinary markers of estrogen-induced tumors, was established in this study. The characteristics of the method that was established were (1) cleanup of urine using the immunoaffinity column of CE SRs, (2) detection of catechol estrogens (CEs) and CE SRs by electrochemical detection, which provided the high specificity, and (3) stability of CE SRs through the cleanup. Using this method, the simultaneous quantitation of 2-hydroxy-17beta-estradiol (2-OHE(2)), 4-hydroxy-17beta-estradiol (4-OHE(2)), 2-hydroxyestrone (2-OHE(1)), 4-hydroxyestrone (4-OHE(1)), 2-hydroxyestrone 1-N-acetylcysteine thioether (2-OHE(1) 1SR), 2-hydroxyestrone 4-N-acetylcysteine thioether (2-OHE(1) 4SR), and 4-hydroxyestrone 2-N-acetylcysteine thioether (4-OHE(1) 2SR) in the range of 1-15 ng was performed. We first demonstrated the presence of CE SRs, 2-OHE(1) 1SR and 2-OHE(1) 4SR, in urine from rats treated intraperitoneally with 17beta-estradiol (E(2)) at a dose of 5 mg/kg. In female rats, the amount of 2-OHE(1) 1SR was several-fold greater than that of 2-OHE(1) 4SR, while the presence of 4-OHE(1) 2SR was not confirmed. The level of CEs and CE SRs in male rats was approximately (1)/(2)-(1)/(20) of that in female rats. The excretion rate following administration of 2-OHE(1) at 2 mg/kg and that following the administration of 4-OHE(1) at 2 mg/kg were different in female rats. In addition, 4-OHE(1) 2SR was present in the urine of male Syrian hamsters treated intraperitoneally with E(2), whereas it was absent in rats.

Acetylcysteine↗
PubMed2000

Disruption of the reproductive system and reproductive performance by administration of nonylphenol to newborn rats.

A number of alkylphenolic compounds are used in a variety of commercial products and have been shown in in vitro studies to be weakly estrogenic, but few in vivo data are available addressing this issue in mammals. Human exposure to alkylphenols may occur not only from these environmental contaminants but also through contact with manufactured and metabolic breakdown products. The reproductive function of rats treated subcutaneously with nonylphenol (NP, 500 mg/kg/day) or 17beta-estradiol (E2, 2 mg/kg/day) as a positive control, from postnatal days 1 to 5 was examined after puberty. In addition, masculine sexual behavior, sperm motion, plasma testosterone concentration and histopathological changes in the reproductive organs of the rats were examined. Furthermore, male rats were subjected to an open field test and wheel cage test to evaluate locomotor activity, and the estrous cycle was examined in female rats. All male and female rats exposed neonatally to NP or E2 showed macroscopic and/or microscopic alterations of the gonads. Females treated with NP or E2 showed an altered estrous cycle and abnormal reproductive function, while males treated with NP or E2 showed normal reproduction. In males exposed neonatally to NP or E2, no abnormalities were observed in locomotor activity, sperm motion or plasma testosterone concentration. The results of this study indicate that early neonatal exposure to NP causes dysfunction of postpubertal reproductive function in female rats, as well as disrupted development of gonads in male and female rats. More detailed studies are warranted to assess the possible risks to human and wildlife reproduction from exposure to NP and other environmental chemicals with estrogenic activity.

Animals↗
PubMed1999

Enzyme immunoassay for the measurement of 17alpha-estradiol 17-N-acetylglucosaminide in rabbit urine.

17alpha-estradiol 17-N-acetylglucosaminide (17alphaE2 17NAG) is an estrogen metabolite hitherto obtained only in rabbits. To gain insight into this unique conjugate, an enzyme immunoassay (EIA) was established by using antiserum elicited against 3-[3-(1-carboxypropyl)] ether of 17alphaE2 17NAG-bovine serum albumin conjugate; horseradish peroxidase, as a label; and 3,3',5,5'-tetramethylbenzidine, as a chromogen. The method proved to be specific, and the detection range of the assay was 0.20-10.00 ng/ml. A proposed double conjugate, 3-glucuronide of 17alphaE2 17NAG, was synthesized to validate the EIA. The EIA was applied to the determination of the urinary level of 17alphaE2 17NAG in male and female (pregnant and non-pregnant) rabbits with and without beta-glucuronidase-sulfatase preparation from Helix pomatia. The results showed that 17alphaE2 17NAG was mainly excreted as a double conjugate (17alphaE2 17NAG 3-glucuronide and/or 3-sulfate) and that its level varies during pregnancy.

Acetylglucosamine↗
PubMed1999

Preparation of specific antisera to 15alpha-hydroxyestrogen 15-N-acetylglucosaminides.

3-(1-Carboxypropyl) ether derivatives of 15alpha-hydroxyestradiol 15-N-acetylglucosaminide (15alpha-OHE2 15NAG) and 15alpha-hydroxyestriol (E4) 15NAG were synthesized and conjugated with bovine serum albumin. Antisera elicited in rabbits possessed high affinity and specificity for the 15alpha-hydroxyestrogen (15alpha-OHEs) 15NAG, exhibiting no significant cross-reactivity with 15alpha-OHEs and their positional isomers such as 16NAG and 17NAG. Enzyme immunoassay methods developed by using the purified antisera and horseradish peroxidase-labeled antigens were applied to the measurement of 15alpha-OHEs 15NAG and E4 15NAG in normal pregnancy urine. We demonstrated for the first time that the conjugation of N-acetylglucosamine to E4 occurs at the C-15alpha position.

Animals↗
PubMed1999

Preparation of specific antisera to 15alpha-hydroxyestrogens.

The synthesis of haptens of 15alpha-hydroxyestrone, 15alpha-hydroxyestradiol, and 15alpha-hydroxyestriol (estetrol) was undertaken, to obtain specific antisera required for enzyme immunoassay. 3-(1-Carboxypropyl) ethers of these 15alpha-hydroxyestrogens were prepared and conjugated with bovine serum albumin and horseradish peroxidase. The specificity of antisera elicited against bovine serum albumin conjugates was checked by the enzyme immunoassay by using horseradish peroxidase-labeled antigen, and proved to be satisfactory in terms of cross-reactivities to related compounds.

Animals↗
PubMed1997

Sex difference in the metabolism of pirmenol in rats.

The in vitro metabolism of pirmenol (cis-alpha-[3-(2,6-dimethyl-1-piperidinyl)propyl]-alpha-phenyl-2-pyri dinemethanol) and glucuronidation of its metabolites, a 4-hydroxylated derivative of pirmenol (M3) and 3-methylether of M3 (M5), were investigated using a hepatic 9000 x g supernatant and microsomes, respectively, of female and male rats in order to elucidate the higher urinary excretion of M3G and M5G (glucuronides of M3 and M5, respectively) in females previously observed in in vivo metabolism. Pirmenol delta1' iminium ion (M2) and M3 were formed by the oxidation of pirmenol in both sexes; however, M2 was the main metabolite in males, while M2 and M3 were formed at nearly the same level in females. On glucuronidation of M3 and M5, the Vmax values of both compounds were higher in female rats, consistent with the results in vivo. In addition, the sex difference in the urinary excretion ratio of M5G to M3G (1.1 in female, 2.5 in male) might reflect the lower availability of M3 for glucuronidation in male rats in vivo. The chromatographic separation of diastereomers of M5G was also described.

Animals↗
PubMed1996

Preparation of specific antiserum to 17 alpha-estradiol 17-N-acetylglucosaminide.

A specific enzyme immunoassay (EIA) method has been developed for 17 alpha-estradiol 17-N-acetylglucosaminide as a model compound instead of 15 alpha-hydroxyestrogen 15-N-acetylglucosaminides. Two new haptens, 3-(omega-carboxyalkyl) ether derivatives of 17-alpha-estradiol 17-N-acetylglucosaminide, were synthesized and conjugated with bovine serum albumin (BSA). The EIA was newly established using specific antiserum elicited against 3-(1-carboxypropyl) ether of 17 alpha-estradiol 17-N-acetylglucosaminide (17NAG CPE)-BSA conjugate and beta-galactosidase-labeled 17NAG CPE as a labeled antigen. An appropriate dose-response curve of EIA for 17 alpha-estradiol 17-N-acetylglucosaminide was obtained in the range of 20-1000 pg/tube. The specificity of EIA proved to be satisfactory in terms of cross-reactivities to related compounds including 15 alpha-N-acetylglucosaminides. The proposed method will be applicable to the preparation of antisera for use in EIA of 15 alpha-hydroxyestrogen 15-N-acetylglucosaminides.

Acetylglucosamine↗
PubMed1993

Comparison of etiological and immunological characteristics of two attenuated Erysipelothrix rhusiopathiae strains of serotypes 1a and 2.

Two acriflavine-fast attenuated Erysipelothrix rhusiopathiae strains Koganei 65-0.15 of serotype 1a (strain Kg-1a) and 2 (strain Kg-2) were comparatively characterized. Biochemical characterization showed the similar reactions with slight variation between the strains. Strain Kg-2 was more resistant to acriflavine dye than strain Kg-1a. Pathogenicity of strain Kg-2 was higher than strain Kg-1a in mice of strains ddY. C3H/He and A/J. Significant differences of clinical signs between strains Kg-1a and Kg-2 were observed in occurrence of arthritis (P < 0.05) and systemic signs (P < 0.01) of only ddY mice. C3H/He mice was more resistant than ddY and A/J mice to the infection of strains Kg-1a and Kg-2. Three culture fractions, whole culture: WC, culture filtrate: CF and killed cells: KC, of strain Kg-2 were more protective than those of strain Kg-1a in ddY mice. CF of strain Kg-2 was most protective in all fractions. Heating at 56 degrees C and 100 degrees C or treatment with trypsin completely reduced the protective activity of WC of the two strains, indicating that major protective antigens of WC were protein. The present results demonstrated that immunogenicity and pathogenicity for mice were different between the two attenuated strains.

Acriflavine↗
PubMed1991

[The effect of prostaglandin E1 (PGE1) on body temperature and on postoperative shivering under high dose epidural fentanyl].

Ninety-nine elective abdominal surgeries were performed under high dose epidural fentanyl anesthesia. PGE1 (0.02 microgram.kg-1.min-1 = 0.02 gamma) was administered to 34 patients (0.02 gamma group), and PGE1 (0.05 gamma) was administered to 16 patients (0.05 gamma group). PGE1 was not administered to 49 patients (control group). The effect of PGE1 on body temperature and on postoperative shivering was compared within three groups. In the 0.02 gamma group, the temperature of the fingertip was significantly higher and the rectum-fingertip temperature gradient was significantly lower than in the other groups. The forearm-fingertip temperature gradient was lower in the 0.02 gamma and 0.05 gamma groups than in the control group. The incidence of postanesthetic shivering was significantly lower in the 0.05 gamma group than in the other groups. These results suggest that; 1) PGE1 (0.02 gamma and 0.05 gamma groups) affects the peripheral blood flow and peripheral temperature, and 2) PGE1 (0.05 gamma group) significantly affects the incidence of postanesthetic shivering.

Abdomen↗
PubMed1990

The effects of ulinastatin on cardiac and hepatic energy metabolism in rats subjected to hypovolemic shock.

Ulinastatin is a trypsin inhibitor extracted from human urine. In this study the effects of ulinastatin on myocardial and hepatic tissue concentrations of creatine phosphate (CP), ATP, ADP, AMP, lactate, pyruvate, and glycogen have been investigated in rats which were in hemorrhagic shock state. Hypovolemia was induced by bleeding from the femoral artery, and systolic blood pressure was maintained 40 mmHg for 25 min, then ulinastatin 50,000 units.kg(-1) in saline or saline vehicle was intravenously administered. Thereafter the heart and liver were extirpated and frozen quickly with liquid nitrogen. The tissue concentrations of CP, ATP, ADP, AMP, lactate and glycogen were measured enzymatically. Systolic blood pressure elevated significantly after ulinastatin administration. The myocardial tissue CP level was higher in ulinastatin-treated group than that of control group, whereas no significant difference in energy charge between two groups. The hepatic tissue level of AMP, lactate and L/P ratio was lower in ulinastatin-treated group than that of control group, however, no significant difference was found in hepatic tissue level of ATP, ADP and energy charge. From these results it is concluded that ulinastatin can improve the energy metabolism of myocardium to some extent, but not of the liver in rats with hypovolemic shock.

Journal Article↗
PubMed1990

Successful surgical treatment of incessant automatic atrial tachycardia with atrial aneurysm.

A 9-year-old boy with heart failure and long-term incessant atrial tachycardia mimicking dilated cardiomyopathy was treated surgically. Intraoperatively he was found to have atrial aneurysm, and the ectopic automatic focus was located at the base of it. Excision of the aneurysm including the focus without using cardiopulmonary bypass cured the tachycardia and heart failure.

Child↗
PubMed1989

[Anesthetic management in surgery of a descending aortic aneurysm in an eighteen-month-old boy].

Aortic aneurysm occurs rarely in childhood. Most aneurysms in children are associated with conditions such as Marfan's syndrome, coarctation of the aorta, Ehlers-Danlos syndrome and neurofibromatosis. We report a case of descending thoracic-abdominal aortic aneurysm in an eighteen month old boy with a mask-like face, ocular hypertelorism, blepharoptosis, a high arched palate and low set ears. He was scheduled for a bypass graft of the descending thoracic and abdominal aorta under partial cardiopulmonary bypass. High dose morphine anesthesia (2mg/kg) was employed and halothane was used to control the blood pressure. To our knowledge, anesthetic management of such an infant had not been reported. Therefore, we anesthetized this child according to anesthetic managements for adult cases considering carefully the boy's multiple anomalies. Anesthetic managements for the surgery of aortic aneurysms in childhood are discussed.

Anesthesia↗
PubMedDate not supplied

Reproductive effects in male and female rats of neonatal exposure to genistein.

Sprague-Dawley rats were administered genistein orally at doses of 12.5, 25, 50, or 100 mg/kg on postnatal days 1 through 5 to examine its effects on reproductive function after puberty. In addition, preputial separation and vaginal opening as endpoints of sexual maturation, estrous cycling, sperm count, serum testosterone concentration, and histopathologic changes of reproductive organs of male and female rats were examined. Body weights of male and female rats exposed to genistein at any dose level examined were lower than those of controls. Timing of preputial separation in males and timing of vaginal opening were not affected by genistein treatment. The number of females showing estrous cycle irregularities was increased by genistein treatment. The fertility of female rats exposed neonatally to genistein at 100 mg/kg was disrupted, while neonatal exposure to genistein did not affect male fertility. Neither sperm counts nor serum testosterone concentration were changed by neonatal exposure to genistein. Female rats exposed neonatally to genistein at 100 mg/kg showed histopathologic changes in the ovaries and uterus, while male rats showed no histopathologic alterations in the gonads. The results of this study indicate that early neonatal exposure to genistein caused dysfunction of postpubertal reproductive performance as well as abnormal development of gonads in female but not in male rats.

Administration, Oral↗