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351.
352.
We conducted an integrated analysis of gene expression and chromatin structure of mouse uterus to understand the regulation of uterine‐expressed genes on gestation day 4 (GD4) during the peri‐implantation period. The genes expressed in the uterus showed a significant association (p < .0001) with the presence of the nucleosome‐free region (open chromatin) in the 5′‐untranslated region of the genes. The majority of these upstream open chromatins harbored a common class of regulatory elements known as upstream open reading frames. We also compared the gene expression profiles between the uterus and brain which showed that specific gene pairs were expressed in a correlated manner, either positively or negatively. In addition, specific ligand/receptor genes showed coordinated patterns of expression between the uterus and brain on GD4, and the level of expression of these ligand/receptors altered significantly in the brain during late pregnancy (GD15) compared with the peri‐implantation period (GD4). Collectively, these results suggest that regulation of the uterine genes during the peri‐implantation period is likely to have a functional link with the maternal brain in pregnant mice.  相似文献   
353.
《Endocrine practice》2021,27(8):765-768
ObjectiveThough gingivitis is common in children with type 1 diabetes mellitus (T1DM), the overall periodontal health in T1DM during the pubertal stage is less well-characterized. The study was undertaken to explore the possible influence of puberty and metabolic derangement on periodontal health in T1DM.MethodsIn this cross-sectional study, 110 subjects between 10-18 years with T1DM and 52 healthy siblings of similar age were evaluated for pubertal stage, glycosylated hemoglobin (HbA1c), and periodontal health. Simplified oral hygiene index (OHIS), gingival index (GI), plaque index (PI), bleeding on probing (BOP), and probing depth (PPD) were evaluated at 4 sites per tooth as per 6 Ramfjord index teeth used to assess periodontal disease (PD).ResultsPD not merely gingivitis was significantly higher in T1DM (84/110, 76.36%) than the control group (28/52, 53.8%) (P = .004). Irrespective of pubertal status, children with T1DM had worse GI, PI, BOP, and PPD than nondiabetic subjects, although OHIS was better in diabetes. In both T1DM and nondiabetic subjects, pubertal subjects showed significantly worse OHIS, PPD, BOP, and GI than prepubertal subjects. PD was correlated with pubertal stage, age, and HbA1c, although less strongly with the duration of diabetes. In logistic regression, pubertal stage was a stronger predictor of PD (OR = 14.26) than age (OR = 2.22), and HbA1c (OR = 1.5) rather than the presence of diabetes and its duration.ConclusionsThough pubertal status, age, and poor glycemic control rather than the presence of diabetes and its duration are associated with gingivitis and other forms of PD, puberty had a more profound effect in the pathogenesis of PD in T1DM.  相似文献   
354.
Uterine fluid is an aqueous milieu to which sperm are exposed during their storage and ascent. In this study, a bottom‐up proteomic strategy and bioinformatic analysis of hen uterine fluid was performed to improve the understanding of this fluid and its potential role in sperm survival mechanisms. The proteomic data were submitted to ProteomeXchange. Among the 913 proteins identified, 160 are known to be secreted and 640 are referenced in exosomes databases. We isolated exosomes from the avian uterine fluid, analyzed them using electron microscopy, and targeted several exosomes markers (ANXA1/2/4/5, VCP, HSP90A, HSPA8, PARK7, and MDH1) using immunoblotting. Electron microscopy and immunohistochemistry were also used to analyze uterovaginal junctions for the exosomal proteins ANXA4, VCP, and PARK7. Exosomes were observed both at the surface epithelium and inside sperm storage tubules. Our data were compared with two previously published studies on proteomic of hen uterine fluid, and with one study describing the proteomic content of rooster seminal plasma and sperm. In conclusion, we demonstrated for the first time that avian uterine fluid contains exosomes. These may play a key role in preserving sperm functions within the female genital tract. Their presence in the sperm storage tubules may represent an important mechanism regarding interaction between the female genital tract and sperm.  相似文献   
355.
Rat identical twins were produced from two-cell embryos. In the presence of cytochalasin B, rat two-cell embryos could be separated efficiently into two blastomeres by micromanipulation. Isolated blastomeres, embedded in agar cylinders and cultivated in ligated rat oviducts for 3 days, developed to the morula or blastocyst stage. After removing the agar, pairs of developed one-half embryos were transferred into Day 1 oviducts or Day 4 uteri of pseudopregnant rats. The percentage of embryos, separated either in the presence or absence of cytochalasin B, that developed into live fetuses was higher in cases of uterine transfer than in cases of oviduct transfer (38% vs. 18%, 31% vs. 15%, respectively). Throughout the present experiment, nine pairs of identical twins were successfully produced. This is the first report of the production of identical rat twins by separating two-cell embryos.  相似文献   
356.
Summary The murine uterine cervix cancer (MUCC) cell line was derived from a chemically induced Kunming mouse uterine cervix cancer (U27) and maintained in culture on solid substrates for over 100 passages. Cultures were morphotypically heterogeneous and heteroploid, with a modal number of chromosomes = 80. Each cell showed at least two abnormal chromosomes. Immunogold-silver staining was positive for keratin, vimentin, and laminin but not for desmin. The population doubling time was 27.8 h with a saturation density of 3.2 × 105 cells/cm2 and a peak mitotic index of about 6%. MUCC cells produced colonies on tissue culture plastic (68%) and in soft agar (8%). MUCC cells were fully malignant inasmuch as they produced in syngeneic mice invasive tumors that reproducibly were metastatic to lymph nodes and lungs. The MUCC cell line is the first mouse cervix cancer cell line useful for the study of invasion and metastasis. Work done at the Laboratory of Experimental Cancerology, Ghent, Belgium, was supported by a grant from the Kankerfonds van de Algemene Spaar-en Lijfrentekas, Brussels, Belgium.  相似文献   
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We describe a non-invasive technique to obtain blood samples from incubating birds without trapping and handling. A larval instar of the blood-sucking bug Dipetalogaster maximus (Heteroptera) was put in a hollowed artificial egg which was placed in a common tern (Sterna hirundo) nest. A gauze-covered hole in the egg allowed the bug to draw blood from the brood patch of breeding adults. We successfully collected 68 blood samples of sufficient amount (median=187 μl). The daily success rate was highest during the early breeding season and averaged 34% for all trials. We could not detect any visible response by the incubating bird to the sting of the bug. This technique allows for non-invasive blood collection from bird species of various sizes without disturbance.  相似文献   
360.
Ultrastructural and light microscopic cytochemical methods were used to study the distribution and changes in distribution of three phosphatase enzymes: 5'-nucleotidase (5N); thiamine pyrophosphatase (TPP); and adenosine triphosphatase (ATP) in the rat endometrium during early pregnancy up to the time of blastocyst attachment. The authors were particularly interested in changes in the apical plasma membrane and reaction product for all three enzymes was clearly localized along this membrane especially on day 1 of pregnancy. However, the three enzymes showed markedly different patterns of organization of reaction product at later times during early pregnancy. 5N, while showing a continuous lining along the microvilli on day 1 was virtually undetectable by day 6. TPP was also strongly present apically on day 1, but reaction product was not always found as a continuous lining. Again, by day 6, there was no presence of this enzyme along the apical surface. ATP differed from the other two in that it produced a strong, and relatively unchanged reaction product along the apical plasma membrane from day 1 through to day 6 of pregnancy. The changes in distribution of these enzymes was particularly obvious at the electron microscopic level and we consider their contribution to the process of 'plasma membrane transformation' of early pregnancy.  相似文献   
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