Specific stimulation of basal lamina heparan sulfate proteoglycan in mouse uterine epithelium by matrigel and by transforming growth factor-β1

Summary The basal lamina of differentiated epithelium normally turns over only slowly unless stimulated by tissue repair and growth. We show here that one mechanism of this stimulation, as modeled by basal lamina proteoglycan synthesis, may be the release of basal lamina-bound transforming growth factor (TGF-β). A large heparan sulfate proteoglycan (HSPG, 0.2K _av on Sepharose CL-4B) that was extractable from mouse uterine epithelium with 4M guanidine-HCl or 1M KCl was recognized by a specific monoclonal antibody to the basal lamina HSPG, perlecan. This HSPG was metabolically inactive with respect to [³⁵S]-sulfate labeling in pieces of whole uterus during 4 h of culture, but it was labeled in isolated cells under the same conditions, provided that the cells had been cultured at least 6 to 12 h before labeling. The rate of labeling was then constant during at least 4 days in culture in serum-containing medium. Cultures on Matrigel showed an enhanced [³⁵S]-sulfate labeling specifically in the 0.2K _av HSPG fraction. Partial stimulation was obtained with a serum-free medium extract of Matrigel, which fractionated on Sephadex G-50 in two components; a major one >30 kDa and the other at about 15 to 25 kDa. The specific stimulation was mimicked by the addition of 10 ng/ml of TGF-β1, but there was no specific stimulation by basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), insulinlike growth factor-1 (IGF-1), or interleukin-1 (IL-1). TGF-β1 was identified as a 12.5 kDa monomer in thiol-reduced Matrigel and Matrigel extracts by polyclonal blocking antibodies on transblots following sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Failure of excess amounts of these antibodies to block Matrigel-stimulated basal lamina HSPG synthesis indicates that TGF-β1 may be only one component of Matrigel that is important in stimulating basal lamina HSPG synthesis in culture. We suggest that in vivo TGF-β1 is bound to macromolecular components of mouse uterine epithelial basal lamina, where it may be sequestered until microenvironmental changes make it available to promote basal lamina HSPG synthesis.     

Development of preimplantation rabbit embryos in uterine flushing-supplemented culture media

The development of cultured rabbit preimplantation embryos grown in standard media (Ham's F-10 or BSM II supplemented with bovine serum albumin (BSA) or homologous serum) or in Ham's medium supplemented with uterine flushings was compared. The uterine flushings derived from donors of 0.5-6 years of age. Uterine flushing supplemented media were used natively or after treatments like sterilization by filtration, lyophilization, three times freezing/thawing, heat denaturation, dialysis, or ultrafiltration. Compared with in vivo controls, embryonic growth was substantially reduced during in vitro culture, demonstrably by smaller diameters and impaired cell proliferation (measured by thymidine incorporation). The growth retardation was more pronounced in blastocysts (recovered at day 4 post coitum [p.c.]) than in morulae (recovered at day 3 p.c.). Development in uterine flushing media was notably better than in standard media but did not comply with in vivo development. Highest thymidine incorporation was observed in media with increased concentrations of uterine secretions and after sequential supplementation of flushings from subsequent progestational stages. Advanced donor ages, heating up to 80 degrees C, freezing, and lyophilizing did not affect incorporation data statistically significantly, whereas sterilization by filtration, ultrafiltration, and dialysis led to a significantly reduced thymidine incorporation in the cultured embryos. The positive effects of uterine flushing supplementation are attributed to the supply of components more adjusted to the needs of the cultured embryos and/or to a reduction of pathological effects in vitro like washing out of nutritive and regulatory components from the embryo into the surrounding culture medium.     

Functional differentiation of mouse uterine epithelial cells grown on collagen gels or reconstituted basement membranes

Summary Epithelial cells were isolated from mouse endometrium and cultured on two types of extracellular matrix, namely, rat-tail collagen (type I) gels and basement membrane extract (BME) derived from the Engelbreth-Holm-Swarm murine sarcoma. Cell attachment in serum-free medium during the initial 24 h after seeding was approximately twofold higher on BME compared with collagen type I. Addition of serum to the medium enhanced cell attachment on both matrices. On both collagen and BME, uterine cells grew as smooth-bordered colonies, and within a week of culture the cells became cuboidal to columnar in shape. Electron microscopy revealed the presence of apical microvilli associated with a glycocalyx, junctional complexes, tonofilaments, short strands of undilated endoplasmic reticulum, Golgi complex, and lipid droplets. However, cells on BME showed a higher degree of differentiation as assessed by occasional formation of small patches of basement membranelike structure subjacent to the flattened basal surface and formation of glandlike structures within the matrix. Proliferation of these cells as measured by radioactive thymidine incorporation into DNA was increased threefold by addition of epidermal growth factor (EGF) and insulin to the medium, but was not changed by 17β-estradiol. The expression of progesterone receptors by uterine epithelial cells grown on both matrices was doubled by addition of EGF and estradiol to the medium. This work was supported in part by a Rockefeller Foundation postdoctoral fellowship (D.G.), and NIh grant 23511.     

早期妊娠兔子宫液WGA和PNA结合糖蛋白的变化

本文利用凝集素为探针,以蛋白质免疫印渍分析法(Western Blot)研究了早期妊娠(D_1至D_(12),交配日定为D_0)兔子宫液中,WGA和PNA两种凝集素结合糖蛋白的动态变化规律,并用凝胶扫描仪对定性结果进行了定量分析。结果表明,着床前后(D_6、D_7和D_9)子宫液中出现分子量分别为42kd和28kd的两种特异WGA结合糖蛋白,妊娠后出现大量分子量为75kd的PNA结合糖蛋白,于着床前(D_6)达高峰,着床后逐渐减少,至D_(12)消失。可见这三种子宫液糖蛋白均为阶段特异性糖蛋白,与着床关系密切。     

Relationship of troponin to incident atrial fibrillation occurrence,recurrence after radiofrequency ablation and prognosis: a systematic review,meta-analysis and meta-regression

Objective: To explore the association between the levels of troponin (Tn) and incident atrial fibrillation (AF) occurrence, AF recurrence after radiofrequency ablation (RFA), and the risk trend of AF related prognosis (stroke, major bleeding and mortality).

Methods: Twenty-seven studies were included after a systematic search in PubMed from 2005 to 2017, including 13 associated with incident AF occurrence, 8 associated with AF recurrence after RFA and 6 studies evaluating the risk trend of AF-related prognosis with increased Tn levels.

Results: Compared with ‘no incident AF occurrence’ patients, the incident AF occurrence group had similar baseline troponin I (TnI) levels (standardized mean differences [SMD]?=?0.42, 95% CI: ?0.02–0.86, p?=?0.06; I²?=?87.0%, N?=?6), but higher troponin T (TnT) levels (SMD?=?3.77, 2.13–5.42, p?<0.001; I²=99.7%, N?=?8). AF recurrence patients had similar peri-ablation TnI levels, but higher peri-ablation TnT levels compared to the ‘no AF recurrence’ group with pooled SMD. (TnI: SMD: ?0.61, ?1.22to 0, p?=?0.049; I²?=?87.1%; TnT: 0.38, 0.14–0.62, p?=?0.002; I²?=?64.7%). On meta-regression, there was an increased risk trend for stroke/systemic embolism (SE) (r²?=?0.93, p?=?0.04) or major bleeding (r²?=?0.99, p?r²?=?0.09, p?=?0.25) or TnT (r²?=?0.20, p?=?0.31), and stroke/SE (r²?=?0.02, p?=?0.74) or major bleeding (r²?=?0.002, p?=?0.92) was non-significantly related to increasing TnI levels.

Conclusions: In our systematic review, meta-analysis and meta-regression, TnT was associated with both incident AF occurrence and AF recurrence after RFA, as well as stroke/SE and major bleeding. In contrast, TnI was not associated with incident AF occurrence, AF recurrence after RFA or prognosis (stroke/SE, major bleeding).     

Effects of ovarian hormones on cell membranes in the rat uterus

Freeze-fracture techniques have been used to study tight junctions on the lateral plasma membrane of cells of the luminal epithelium of the rat uterus under various hormonal regimes. Tight junctions from ovariectomized control rats extended some 0.5 μm down the lateral membrane and the junctional strands often formed a network of closely packed, circular compartments. Following treatment of rats with estrogen for 3 days the tight junctional regional still extended 0.5 μm down the lateral membrane, but the strands ran more parallel to the apical surface. They did not enclose circular compartments. After treatment with progesterone, either alone or with estrogen in such a way as to condition the ovariectomized uterus for implantation, a third pattern of junctional organization emerged. In these animals the junctional region extended 1.1 μm down the lateral membrane and the strands frequently crosslinked, enclosing compartments of varying and irregular size and shape. Our observations suggest that ovarian hormones could regulate the contents of the uterine lumen by altering the structure extent of the tight junctions which connect the epithelial cells enclosing the lumen.     

Light control of periodicity of bleeding from roots of Vicia faba

The light control of the periodicity of bleeding sap was investigated, and it appears that the metabolic activity of the roots controls the exudation. Nitrite, nitrate, fructose, glucose and sucrose, various amino acids and some other unidentified compounds, were detected in the bleeding sap.     

Phospholipid Containing Choline Histochemistry of Mouse Uterine Epithelia during Preimplantation Stage

The physiological role of high lipid content in endometrial cells during pregnancy has not been well established. In the present work we used histochemical techniques to analyze the total lipids and phospholipid containing choline (PCC) in the mouse uterine glandular and luminal epithelia during preimplantation stage. Sudan black histochemistry showed the highest intensity during the second day of pregnancy in both the basal and apical portions of luminal epithelium. Peaks of PCC staining were seen both in the luminal and glandular epithelia at the second and fifth days of pregnancy. Changes in localization and in the amount of lipid in the uterine epithelia suggest high mobility and metabolic rates of this substance, which maybe related to morphological and/or functional changes occurring at the same time in the pregnant uterus. The increase and depletion timing of PCC content in the uterine epithelia during preimplantation stage, when uterine prostaglandin is also oscillating, suggest a possible involvement of PCC in prostaglandin biosynthesis. Therefore, the fate of lipid droplets found in the uterine epithelia may be related to critical changes of the pregnant endometrium, rather than the nourishment of developing embryos alone.     

Changes in kinetic properties of oxytocin receptors in longitudinal muscle membranes of rat uterus during gestation

Receptors of oxytocin were found to occur in the membrane fraction obtained from longitudinal muscle of pregnant rat uterus. The affinity of the membrane receptor for oxytocin increased through an increase in the association rate and a decrease in the dissociation rate during gestation. The membrane oxytocin receptor concentrations rose almost three-fold from Day 15 to Day 21. A transition of oxytocin receptors from a single class of independent sites to site–site interacted multiple binding sites, which most likely exhibit positive cooperativity during the last seven days of gestation, was observed. These results suggest that changes in the dynamics of uterine oxytocin receptors also play an important role in the onset of labor.     

Effect of radiotherapy and chemoradiotherapy on circulating antioxidant system of human uterine cervical carcinoma

Circulating lipid peroxide, antioxidant components and the activities of defense enzymes were estimated in uterine cervical carcinoma patients (before and after radiotherapy and radiotherapy combined chemotherapy) and compared with controls. Some of the antioxidant components such as glutathione, vitamin E and selenium are reduced in cervical cancer. The reduced levels of vitamin E and glutathione were normalized after treatment. Erythrocyte lipid peroxide (E-LPx) and erythrocyte membrane lipid peroxide (EM-LPx) levels were found to be increased in all the stages of uterine cervical carcinoma. The important antioxidant enzymes such as erythrocyte superoxide dismutase (E-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) and glucose-6-phosphate dehydrogenase (G6PDH) were found to be decreased in uterine cervical carcinoma. These altered biochemical parameters were reversed to normal, of course with varied degree after different mode of therapy. Significant normalization was observed in Type 11 chemoradiotherapy.