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411.
Although the human and the nonhuman primate fetal adrenal glands undergo a highly unique pattern of cortical zone-specific intrauterine growth and development, studies of the regulatory components of the cell cycle responsible for this growth have not been conducted. Therefore, the present study determined expression of the cell cycle regulators, cyclin D1 and cyclin E, and their cyclin-dependent kinases, Cdk2, Cdk4, and Cdk6, and Ki67 a marker of cell proliferation within the baboon fetal adrenal cortex during advancing stages of gestation. Fetal adrenal glands were obtained on days 60 (early), 100 (mid), and 160-170 (late) of gestation (term = 184 days). Mean (+/- s.e.) cyclin D1 mRNA levels, determined by RT-PCR and expressed relative to 18S rRNA, were similar at early (0.85 +/- 0.09) and mid (1.04 +/- 0.08) gestation, then decreased (P < 0.001, ANOVA) approximately 50% by late gestation (0.57 +/- 0.04). Cyclin E mRNA levels were also similar at early (2.03 +/- 0.07) and mid (1.63 +/- 0.31) gestation, and decreased by 70% (P < 0.001) in late gestation (0.53 +/- 0.09). Coinciding with the decrease in cyclin D1 and cyclin E, the percentage of Ki67 positive cells in the definitive zone decreased twofold (P < 0.01) between mid (28.2 +/- 3.6) and late (13.8 +/- 1.7) gestation. The cyclin D1 and cyclin E proteins, determined by immunocytochemistry, were expressed at high levels in the definitive zone of baboon fetal adrenal gland, where they decreased between mid- and late gestation. In contrast, immunocytochemical expression of the functionally important steroidogenic enzyme Delta(5)-3beta-hydroxysteroid dehydrogenase (3beta-HSD) became abundant in the definitive and transitional zones with advancing pregnancy. However, fetal adrenal Cdk2, Cdk4, and Cdk6 mRNA levels and protein immunoexpression were similar in the baboon fetal adrenal at early-, mid-, and late gestation. In summary, expression of cyclin D1, cyclin E, and Ki67 decreased, while 3beta-HSD expression increased, in the fetal adrenal cortex, particularly in the definitive zone, between mid- and late-baboon gestation. We propose that a developmental decline in cellular proliferation permits functional differentiation of fetal adrenal cortical cells, leading to increased production of steroid hormones important for placental estrogen synthesis and maturation of organ systems within the developing fetus. 相似文献
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413.
Adelina Silvana Gheorghe Elena Adriana Dumitrescu Isabela Anda Komporaly Raluca Ioana Mihil Cristian Virgil Lungulescu Dana Lucia Stnculeanu 《Current oncology (Toronto, Ont.)》2022,29(4):2835
This review of the meaningful data from 2021 on cervical, endometrial, and ovarian cancers aims to provide an update of the most clinically relevant studies presented at important oncologic congresses during the year (the American Society of Clinical Oncology (ASCO) Annual Meeting, the European Society for Medical Oncology (ESMO) Congress and the Society of Gynecologic Oncology (SGO) Annual Meeting). Despite the underlying existence of the COVID-19 pandemic, the last year has been notable in terms of research, with significant and promising advances in gynecological malignancies. Several major studies reporting the effects of innovative therapies for patients with cervical, endometrial, and ovarian cancers might change the medical practice in the future. 相似文献
414.
Cristina-Rodica Dumitrescu Vasile-Adrian Surdu Hermine Stroescu Adrian-Ionut Nicoara Ionela Andreea Neacsu Roxana Trusca Ecaterina Andronescu Lucian Toma Ciocan 《Materials》2022,15(15)
For more than five decades, alkali niobate-based materials (KxNa1−xNbO3) have been one of the most promising lead-free piezoelectric materials researched to be used in electronics, photocatalysis, energy storage/conversion and medical applications, due to their important health and environmentally friendly nature. In this paper, our strategy was to synthetize the nearest reproductible composition to KxNa1−xNbO3 (KNN) with x = 0.5, placed at the limit of the morphotropic phase boundary (MPB) with the presence of both polymorphic phases, orthorhombic and tetragonal. The wet synthesis route was chosen to make the mix crystal powders, starting with the suspension preparation of Nb2O5 powder and KOH and NaOH alkaline solutions. Hydrothermal microwave-assisted maturation (HTMW), following the parameter variation T = 200–250 °C, p = 47–60 bar and dwelling time of 30–90 min, was performed. All powders therefore synthesized were entirely KxN1−xNbO3 solid solutions with x = 0.06–0.69, and the compositional, elemental, structural and morphological characterization highlighted polycrystalline particle assemblage with cubic and prismatic morphology, with sizes between 0.28 nm and 2.95 μm and polymorphic O-T phase coexistence, and a d33 piezoelectric constant under 1 pC/N of the compacted unsintered and unpoled discs were found. 相似文献
415.
【Objective】 To investigate effects of combined usage of dynamic neuro-electric stimulation(DNES) and M-cholynolytic therapy(oxybutynin) upon manifestations of neurogenic bladder dysfunctions(NBD) in children.【Method】 Urodynamics examination included registration of extemporaneous urinary excretion,urofluometry,and retrograde cytometry in horizontal and vertical position by example of urodynamic system(UDS) ACS 180 Plus(MENFIS BioMed.,USA).In accordance to severity of clinician manifestations,three groups of patients have been defined(27-highest one,49-middle and 51 low levels).Dynamic neuro-electrostimulation(DNES) procedures were conducted using the"DiaDNES-PKM"device(Russian Federation).The children were exposed to juxtaspinal stimulation on S1-S3 level-altogether 10 sessions have been performed.Oxybutynin(driptan) was used in dosage of 2.5 mg per diem.【Result】It was established that combined usage of DNES and oxybutynin in the group with highest severity caused the reduction of manifestations by 3.1 times while separately given DNES and basic therapy were followed by 34.1% and 28.0% reduction correspondently.Meanwhile,DNES and oxybutynin reduced severity in patients with pronounced disturbances by 7.5 times.Combined usage of oxybutynin and DNES in severely manifested NBD increased the effective volume of bladder by 2.3 times.Also significant reduction of both intrabladder pressure(by 48.0%) and compliance of the bladder(by 4.8 times) were detected under condition of combined usage of DNES and oxybutynin.All mentioned indices were modified to less extent in case of separate usage of DNES or oxybutynin when compared with the one registered after the combined their usage(P <0.05).【Conclusion】Combined usage of DENS and oxybutinin(driptan) is effective in most severe cases in children suffered from neurogenic overactive bladder. 相似文献