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K Omoe

Publications and source records attributed to K Omoe.

27 records · Page 2Linked to original sources
PubMed1994

Expression level of Rps4 mRNA in 39,X mice and 40,XX mice.

Contrary to the effects of X-chromosome monosomy in humans (Turner syndrome), XO mice are fertile and anatomically normal. The human RPS4X gene encodes ribosomal protein S4 and escapes X-chromosome inactivation, and its haplo-insufficiency has been suspected to contribute to Turner syndrome. Therefore, we compared the expression level of mRNA of Rps4 (the mouse homolog of RPS4X) between XX and XO mice using Northern blot analysis. The XO/XX ratio of Rps4 mRNA obtained from Northern blot analysis was 0.9. There was no difference in the expression level of Rps4 mRNA between XX and XO mice. The difference in the RPS4/Rps4 transcription pattern between humans and mice may contribute, at least in part, to the phenotypic difference in monosomy X between humans and mice.

Aneuploidy↗
PubMed1993

Ecological factors affecting body size of Japanese adolescents.

Prefectural data of 17-year-old Japanese adolescents' body size were excerpted from the annual series of Reports on School Health Statistics (Ministry of Education) for the last 35 years, and were correlated with the mean annual temperature of prefectural capitals. A negative correlation was found for both height and weight. Thus, it can be stated that children in colder climates conform to Bergmann's rule that they are larger in their height and weight than children growing up in warmer climates. Partial correlation coefficients indicate that body weight is primarily related to the temperature. Further, the results of a multiple regression analysis, using temperature, daily energy intake (National Nutrition Surveys), and annual per capita income (Annual Reports of Prefectural Accounts) as the independent variables among the 12 districts (groups of prefectures) for the last 25 years, suggest that the observed Bergmann's phenomenon is related to geographical differences in nutrition; people in colder regions consume more calories than those in warmer regions.

Adolescent↗
PubMed1993

Growth and development of 39,X mouse embryos at mid-gestation.

We examined the growth and development of XO embryos at mid-gestation (day 10) by assessing crown-rump length, head length, somite number, and morphological score (Van Maele-Fabry et al., 1990), using an XO mouse colony established from the Jcl/ICR strain. Contrary to expectation, there were no differences between the XO and XX embryos in any parameter measured. Also, no particular region was specifically retarded in XO embryos during development. We therefore concluded that the growth and development of XO embryos were not retarded when compared with their XX littermates at day 10 of gestation.

Animals↗
PubMed1992

Growth and differentiation schedule of mouse embryos obtained from delayed matings.

We previously showed that digit formation in mouse embryos from early morning mating seemed to progress faster than those from overnight mating. In this study, to confirm this phenomenon, we examine whether the embryos from normal (0 hr from ovulation to fertilization) and delayed matings (3, 6, or 9 hr from ovulation to fertilization) respond differently to some acute teratogens when they are treated at the same time point from mating. Five mg/kg of cytosine arabinoside (Ara-C) was given to pregnant mice intraperitoneally at 246, 249, or 252 hr (day of gestation (dg) 10) after mating. The patterns of Ara-C induced digit malformations in embryos from the delayed mating groups were those of more advanced stages, when compared with normal mating groups with the same time intervals from mating to Ara-C treatment. In other words, oocytes fertilized up to 9 hr after the presumed time of ovulation could grow similarly to those of normally fertilized oocytes. This catch-up phenomenon suggests that the ovulation clock should be used for the startpoint of the time scale of the growth and differentiation of embryos rather than fertilization clock.

Animals↗
PubMed1992

Susceptibility to teratogenicity of hypervitaminosis-A in X-monosomy mice.

We previously showed that the incidence of external malformations induced by biotin deficiency did not differ either between XO and XX dams or between XO and XX fetuses. To clarify whether this phenomenon is specific to biotin deficiency or more generally associated with other teratogens, we examined whether XO mice are more susceptible to teratogenic effects of hypervitaminosis-A. Pregnant XO and XX mice were given an excessive vitamin A diets (1.0 to 1.5 x 10(6) IU/kg) from days 0 to 17 of gestation. Maternal hypervitaminosis-A produced a high incidence of external malformations (65 to 80%), skeletal anomalies (33 to 47%), and variations (99 to 100%) in the fetuses. However, there is no difference in their incidences between XO and XX dams or between XO and XX fetuses. Together with previous findings, this suggests that developmental stability of the mouse embryo is not affected by missing of one whole X chromosome even with exposure to teratogens.

Aneuploidy↗
PubMed1992

Compensatory development in preimplantation mouse embryos derived from delayed mating.

Rodent embryos resulting from delayed mating grow relatively faster than those resulting from normal mating. To evaluate this phenomenon quantitatively, in the present study we compared the number of cells at the preimplantation stage of mouse embryos derived from normal mating and those derived from delayed mating (3 and 6 h after ovulation). The mean cell numbers (45.4 and 43.0 for delayed mating at 3 and 6 h postovulation, respectively) of embryos at 77 h postcoitus (hpc) in the delayed mating groups were greater than that (38.4) of the normal mating group. Further, when the mean cell numbers (38.8 and 38.5) in the delayed mating groups were counted at 74 hpc, they were almost equal to that of the normal mating group at 77 hpc. The study demonstrated that preimplantation mouse embryos derived from delayed mating progress more rapidly than their normally mated counterparts. However, a 3-h advance in development seems to be the limit of this increased rate of growth, even when the time interval from ovulation to mating is longer than 3 h. The mechanism(s) of this interesting compensatory phenomenon should be investigated.

Animals↗
PubMed1992

Origin and evolutionary characteristics of antigenic reassortant influenza A (H1N2) viruses isolated from man in China.

During the 1988/1989 influenza season, five antigenic reassortant influenza A (H1N2) viruses not previously isolated from man were isolated in Hebei province, People's Republic of China. All isolates contained haemagglutinins (HAs) and neuraminidases (NAs) which were antigenically similar to those of the recent Russian (H1N1) and Hong Kong influenza A (H3N2) viruses, respectively. The results of antigenic and nucleotide sequence analyses revealed that the genes encoding the polymerase, nucleoprotein, NA, matrix and non-structural proteins of the reassortant A/Hebei/24/89 (H1N2) virus were derived from the H3N2 parent virus, whereas its HA gene was from the H1N1 parent virus. The nucleotide sequences of the HA (encoding the HA1 subunit) and NA genes of the reassortant viruses were also determined. Phylogenetic trees constructed from these data by the neighbour-joining method revealed that the HA gene of the reassortant virus was closely related to those of recent human H1N1 viruses, whereas the NA gene was related to a recent human Hong Kong (H3N2) virus lineage.

Antigens, Viral↗
PubMed1991

Immunological studies on staphylococcal enterotoxin D: production of murine monoclonal antibodies and immunopurification.

Eight murine monoclonal antibodies (MAbs) against staphylococcal enterotoxin D (SED) were obtained by fusion of myeloma cells with mouse spleen cells immunized with SED only or a combination of SED and either enterotoxin A (SEA) or enterotoxin E (SEE). When only SED was used as an immunogen, six MAbs were specific for SED only, whereas one MAb was reactive with both SED and SEE when both SEs were used as immunogens. One MAb reacted with SEA, SED, and SEE when both SEA and SED were used as immunogens. A MAb with the highest reactivity to SED was used to prepare an immunosorbent for purification of SED by immunoaffinity chromatography. Approximately 70% of the partially purified SED was recovered in the eluate. The purified SED was electrophoretically and antigenically pure. Immunoaffinity chromatography proved useful in the purification of SED in terms of ease of purification, percent enterotoxin, and enterotoxin purity.

Animals↗