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O Taguchi

Publications and source records attributed to O Taguchi.

At least 145 records · Page 8Linked to original sources

Hypertrophic gastritis with hypergastrinemia and protein loss after neonatal thymectomy in mice.

Hypertrophic gastritis, histologically characterized by a depletion of parietal and chief cells and by varying degrees of lymphocyte infiltration along the thickened muscularis mucosa, could be induced by neonatal thymectomy (Tx) without any additional treatment in about 50% of mice (C3H/HeMs X 129/J)F1 (C3.129). The thickness of the mucosa in gastritic mice increased with age, forming giant folds. In Tx mice with an early stage of abnormal mucosal folds at 6 months of age, numbers of parietal cells per mucosal tissue unit area (parietal cell densities) and ratios of parietal cells to mucous cells became lower than in control mice, and serum gastrin levels became contrastingly higher with the increasing severity of gastritis. Circulating antibodies against parietal cells (APA) were detected by indirect immunofluorescence (IFL) in the mice. A good correlation was observed between APA and gastritis: APA with high titers (more than 1,000-fold dilutions) appeared when severe lesions were found. In mice with giant mucosal folds at 18 months of age, serum protein levels were within normal limits, but fecal clearance rates of 125I-labelled polyvinylpyrrolidone (125I-PVP) were significantly increased. These results suggest that the hypertrophic gastritis induced by neonatal Tx is characterized by hypergastrinemia due to parietal cell depletion caused by the presence of circulating APA and the protein loss from the hypertrophic mucosa. Both histological and physiopathological similarities were found between the gastritis in the mice and Menetrier's disease in man.

Animals↗

Direct-writing recorder of the frequency dependence of dynamic compliance analyzed from one cycle of breathing and pulmonary resistance: effect of fenoterol on asthmatic subjects.

We developed a new method of direct-writing recording of the frequency dependence of dynamic compliance analysed from one cycle of breathing and pulmonary resistance. Both pulmonary resistance (RL) and frequency dependence of dynamic compliance (Cdyn.f) are calculated by Fourier-series analysis of flow and transpulmonary pressure in a single cycle of breathing. RL was obtained from fundamental harmonics. Cdyn.f was calculated from 1st and 2nd harmonics and estimated by the ratio of Cdyn at 0.5 Hz to Cdyn at zero frequency, C0.5/C0. We used fenoterol aerosol which contained 0.2 mg of fenoterol with one puff of aerosol. Two puffs of fenoterol aerosol were used in each subject and followed changes of RL, C0 and C0.5 as long as 30 min. After fenoterol inhalation RL decreased considerably and C0.5/C0 cont [C0.5/(control C0)] increased. With time, while RL was kept stable, C0.5/C0 cont increased further. We suggest that fenoterol has a potent effect on the small airways which is enhanced with time.

Administration, Inhalation↗

Reproductive tract abnormalities in female mice treated neonatally with tamoxifen.

Immature female mice of the NMRI strain were treated with 20 micrograms/day of tamoxifen or vehicle for the first 3 days after birth. At 90 days of age, vaginas, uteri, and ovaries were examined histologically. A benign epithelial change, vaginal adenosis characterized by abnormal growth of columnar epithelium with glandular structures, was found in all of the tamoxifen-treated mice. Anatomic anomalies such as hypospadias, cervical hypoplasia, uterine hypoplasia, and absence of corpora lutea also were commonly observed. Such abnormalities were not found in the control mice.

Abnormalities, Drug-Induced↗

Experimental autoimmune prostatitis after neonatal thymectomy in the mouse.

Experimental autoimmune prostatitis (EAP) could be induced in (C3H/HeMs X 129/J)F1 mice by thymectomy (Tx) at 3 days (Tx-3) but not at 0 or 7 days after birth. Appearance of EAP was noticed in the three lobes of the prostate, most frequently and severely in the anterior lobe (coagulating gland). EAP thus induced was characterized by a loss of secretory products in the lumen, massive lymphocytic infiltration in the stroma, especially beneath the epithelial cells, and by the presence of circulating autoantibody(ies) against the epithelial cells of the prostate (APA). EAP started at puberty and its incidence was 68% in 50-150 day old mice. APA was completely absorbed with the homogenates of prostate but not of seminal vesicles, testes or livers of the mouse. High titres of APA, detectable in sera of more than 1,000-fold dilutions accompanized with the severe lesion, were assayed by indirect immunofluorescence (IFL) technique. No sign of EAP was seen in the immature prostate of 90 day old mice which were orchidectomized at 0 day (Orx-0) followed by Tx-3. Exogenous androgen treatment at an adult age induced EAP in these Orx-0 plus Tx-3 mice. The findings indicate that mice which received Tx at a critical neonatal age develop EAP by autosensitization to the antigen(s) normally expressing in the differentiated prostate.

Animals↗

Timing and irreversibility of Müllerian duct inhibition in the embryonic reproductive tract of the human male.

A study was undertaken to determine (1) the effects of endogenous Müllerian inhibiting substance (MIS) on the developing human fetal genital tract; (2) the time in fetal life when MIS is first capable of inhibiting the growth of the embryonic Müllerian ducts; and (3) the reversibility of the effects of MIS on the developing male Müllerian ducts. Human fetal reproductive tracts were transplanted and grown for sustained periods in vivo in athymic nude mice. The genital tracts from 12 male human fetuses, ages 51 to 68 days postovulation, were grafted without their associated gonads into castrated murine hosts and grown for 30 to 70 days. Controls consisted of genital tracts from 8 female human fetuses, ages day 53 to 70 that were grown under identical conditions. Male specimens grew to approximately one-half the size of female specimens and disclosed varying degrees of inhibition of the Müllerian duct system from absence of the Müllerian ducts in older specimens (after Day 63) to poorly segregated segments of stroma as the mildest defect (less than Day 61). It is concluded that (1) MIS secretion by the embryonic testes probably begins before Day 51 of gestation; (2) the effects of MIS are progressive during the so-called critical window; (3) the effects of MIS are permanent; and (4) the mesenchyme is an important target of MIS.

Animals↗

Epithelial-mesenchymal interactions in prostatic development. II. Biochemical observations of prostatic induction by urogenital sinus mesenchyme in epithelium of the adult rodent urinary bladder.

Adult bladder epithelium (BLE) is induced to differentiate into glandular epithelium after association with urogenital sinus mesenchyme (UGM) and subsequent in vivo growth in syngeneic male hosts. Alteration of epithelial cytodifferentiation is associated with the expression of prostate-specific antigens, histochemical and steroid metabolic activities. These observations suggest that the inductive influence of the UGM has reprogrammed both the morphological and functional characteristics of the urothelium. In this report, differences regarding the mechanisms and effects of androgenic stimulation of prostate and bladder are exploited to determine the extent to which UGM plus BLE recombinants express a prostatelike, androgen-dependent phenotype. Results from cytosolic and autoradiographic binding studies suggest that androgen binding is induced in UGM plus BLE recombinants and that this activity is accounted for by the induced urothelial cells. In UGM plus BLE recombinants, androgen-induced [3H]thymidine or [35S]-methionine uptake analyzed by two-dimensional gel electrophoresis was qualitatively and quantitatively similar to that of prostate as opposed to bladder. These studies indicate that expression within BLE of prostatic phenotype is associated with a loss of urothelial characteristics and that androgen sensitivity is presumably a function of the inductive activities of the stroma.

Animals↗

Experimental study of the effect of diethylstilbestrol on the development of the human female reproductive tract.

Female genital tracts from human embryos and fetuses 5-17 weeks post fertilization were grown for 1-3 months in vivo as grafts to athymic female nude mice. The nude mice were either untreated or treated with diethylstilbestrol (DES). In control (untreated) hosts, anticipated normal development occurred with a high degree of precision. Müllerian ducts fused and proliferated, forming a solid uterovaginal canal that later canalized and formed a normal vaginal mucosa. Uterine glands appeared, and the uterine tube developed its highly plicated mucosa. Under the influence of DES, many of these normal developmental processes were adversely affected. Müllerian epithelium was largely obliterated in the fallopian tube and uterine corpus, mesenchymal stratification into endometrial stroma and myometrium was suppressed, plical development in the fallopian tube was inhibited, cervicovaginal epithelial development was abnormal, and vaginal adenosis was observed in several specimens. This in vivo model of human development is discussed in terms of its potential for resolving the mechanisms of normal human genital development and understanding the teratogenic action of DES on the developing human genital tract.

Animals↗

Normal development of the human female reproductive tract and alterations resulting from experimental exposure to diethylstilbestrol.

An in vivo model is described for the study of human uterovaginal development in the presence and absence of the teratogenic drug diethylstilbestrol (DES). Intact reproductive tracts from fragments of 29 human embryos and fetuses 5.0 to 17.7 weeks of age obtained after dilatation and curettage were grown for four weeks in vivo in athymic (nude) mice that were either untreated (control) or implanted subcutaneously with a DES pellet. Control specimens grown in vivo continued their anticipated morphogenesis for equivalent in-utero ages; the normal processes observed included fusion of the paired embryonic müllerian ducts into a single uterovaginal canal, stratification of endometrial and tubal mesenchyma into inner (presumptive endometrial stroma) and outer (presumptive myometrium) layers; plication of tubal and endometrial mucosa; uterine gland formation; and stratification (transformation) of the simple columnar epithelium of the vagina and cervix into a stratified squamous plate. Specimens exposed in vivo to DES exhibited anomalies, many of which mimicked those observed clinically in young women exposed prenatally to DES. Glandular epithelium (adenosis) was found in the vagina. The upper genital tract was malformed; its growth was stunted, and the inner and outer stromal layers of the uterine corpus and fallopian tubes failed to segregate. The authors conclude that the in vivo model that they describe, with its built-in controls, provides a valid approach for examining the dynamics of morphogenesis and cytodifferentiation in developing human genital tracts under experimentally regulated conditions.

Animals↗

Autoradiographic localization of steroid binding in human tissue labeled in vitro.

A procedure for the rapid preparation of autoradiograms from tissues incubated in vitro with 3H-estradiol is described. Slices of tissue were incubated in culture medium containing 17 nM 3H-estradiol, washed to remove unbound steroid, then processed for thaw-mount autoradiography. Exposure times were generally 3 to 4 weeks. Simultaneous in vitro competition with unlabeled progesterone, dihydrotestosterone, or hydrocortisone had no effect on the distribution or intensity of exposed silver grains, while competition with unlabeled estradiol or moxestrol abolished nuclear localization of silver grains. The exchange of labeled estradiol for bound endogenous estradiol during in vitro incubation of the tissues was demonstrated by a comparison of the pattern of incorporation of 3H-estradiol in tissues previously treated in vivo with unlabeled estradiol versus those not primed. A similar distribution and intensity of silver grains was observed in both the treated and untreated tissue groups. The rationale for the advantages of in vitro steroid autoradiography versus the in vivo technique is discussed.

Adult↗

Mesenchymal-epithelial interactions in hormone-induced development.

An hypothesis of hormone action upon epithelial growth, morphogenesis and cytodifferentiation is proposed in which certain hormonal effects upon epithelial cells are postulated to be mediated by nonsteroidal growth factors or morphogens elaborated by hormone-sensitive mesenchymal cells. Through this process mesenchymal cells induce specific patterns of epithelial morphogenesis and functional (biochemical) activity within urogenital epithelium.

Animals↗

Mesenchymal-epithelial interactions in sex differentiation.

Development of male and female accessory sexual glands is described in terms of the respective roles of epithelium and mesenchyme. During embryonic and neonatal periods mesenchyme alone exhibits androgen receptor activity (nuclear androgen binding sites) and is the actual target and mediator of the morphogenetic effects of androgens upon the epithelium. Mesenchyme induces specific patterns of epithelial morphogenesis, cytodifferentiation, and probably also specifies the functional (biochemical) activities of the epithelium. Mesenchymal influence upon expression of epithelial characteristics occurs in the perinatal period during morphogenesis, but also plays an important role in adulthood by maintaining favorable conditions for maintenance of epithelial morphology and function. Morphogenetic processes in adult hormone-dependent organs are though to be mediated by stromal cells.

Androgens↗

Changes in hypophyseal hormones associated with accelerated aging and tumorigenesis of the ovaries in neonatally thymectomized mice.

Neonatal thymectomy at 3 days of age in mice results in ovarian dysgenesis, characterized by early follicular and oocyte loss, followed by a high incidence of ovarian tumorigenesis. Thymectomized animals with dysgenetic ovaries had extremely high levels of circulating PRL and gonadotropins before the appearance of the ovarian tumors, supporting the hypothesis that prolonged stimulation by gonadotropic hormones induces ovarian tumors. The levels of LH and FSH, however, were low by the time the tumors actually appeared, indicating a lag period between hormonal stimulation and the actual onset of the tumors. The data suggest that since thymectomized female mice exhibit a hastening of reproductive aging, these animals may be useful models for studying aging of the reproductive system, including the hormonal events which precede tumorigenesis.

Aging↗

Experimental autoimmune orchitis after neonatal thymectomy in the mouse.

Experimental autoimmune orchitis (EAO) developed in (C57Bl/6Cr x A/JCr)F1 mice 3-4 months after neonatal thymectomy (Tx) without any sensitization. The age of Tx was critical for induction of EAO: Tx at day 3 (Tx-3) was effective, but Tx at day 0 or day 7 was not effective. This lesion resulted in atrophy of the testis and was characterized by disappearance of mature sperms, formation of multinuclear giant cells in seminiferous tubules and infiltration of lymphocytes in the stroma. Epididymitis was observed prior to the development of EAO. Presence of circulating autoantibody(s) against sperms (ASA) was demonstrated by indirect immunofluorescence. The acrosomal area of mature sperms, but not of immature spermatids, was strongly. The incidence of EAO and titre of ASA increased when Tx-3 mice were unilaterally vasectomized (Vx). The majority of mice with high titres of circulating ASA were sterile. Epididymitis and orchitis could be prevented in Tx-3 mice by injection of adult spleen cells on day 4. The most effective source was normal male. Spleen cells from normal female donors and day-0 orchidectomized (Orx) donors were less effective, while those of Tx-3 male and female donors failed to prevent epididymis and orchitis. The cell population in normal male spleen effective in preventing epididymitis was shown to be a T cell population (Thy 1+, Ig-) by experiments with respective antisera treatment. These results showed that sensitization with sperm autoantigen occurred in the epididymis after Tx-3, more efficiently after Tx-3 plus unilateral Vx, and that this autosensitization was prevented by a specific suppressor T cell population, which was present in normal males but absent in Tx-3 mice.

Animals↗

Fine structure of giant hypertrophic gastritis developed in thymectomized mice.

(C3H/HeMs x 129/J)F1 mice were thymectomized at 3 days of age, and their stomachs were examined by electron microscopy at 3, 6, and 18 months of age. A hypertrophic type of gastritis developed in about half the mice, the fundus being chiefly affected. In the early stage, thickening of the mucosa was attributed mainly to an elongation of the glandular part, but in the later stage it was attributed to both elongated glandular tubules and proliferated foveolar cells. Mature parietal and chief cells were preferentially reduced in number, and immature counterparts were relatively marked in the glandular portion. Thus, the proportion and grade of maturation of these cells in gastritic mice were different from those in normal mice. Foveolar and glandular mucous cells, resembling, respectively, normal surface mucus and mucous neck cells, were the major cell types of the glands. Undifferentiated cells were also frequently encountered. Hyperplasia of endocrine cells, particularly ECL and G cells in the fundic and pyloric mucosa, respectively, was also documented. These results suggest that the gastric hypertrophy of gastritic mice was triggered by the disturbances in differentiation and maturation of parietal and chief cells.

Animals↗

Autoimmune oophoritis in thymectomized mice: T cell requirement in adoptive cell transfer.

Experimental autoimmune oophoritis characterized by rapid loss of oocytes with infiltration of lymphocytes and circulating anti-oocyte antibodies could be induced in (C57Bl/6Cr x A/JCr)F1 mice after thymectomy (Tx) at a critical age of 3 days (Tx-3) but not 0. or 7 days after birth without any sensitization. The lesion of the ovary was passively transferred into neonatal, but not adult, mice 7 days after intraperitoneal (i.p.) injection of spleen cells (10(7)) obtained from syngeneic donors with oophoritis. In contrast, the lesion was never evoked in the recipient ovaries when spleen cells were prepared from Tx-3 mice ovariectomized at day 0. The spleen cells prepared from Tx-3 donors, depleted of T cells by incubation with anti-Thy 1.2 antiserum plus guinea-pig complement (GPC), showed no transfer capacity. However, the spleen cells prepared from the same donors, depleted of B cells with anti-Ig antiserum plus GPC, still kept the capacity to induce oophoritis. The results indicate the presence of autoreactive T cells against ovarian tissues in Tx-3 mice which are capable of inducing oophoritis.

Age Factors↗