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Francesca Passaretta Domenico Bosco Lucia Centurione Maria Antonietta Centurione Fabio Marongiu Roberta Di Pietro 《Journal of cellular and molecular medicine》2020,24(7):4350-4355
Human Amniotic Epithelial Cells (hAEC) isolated from term placenta are a promising source for regenerative medicine. However, it has long been debated whether the hAEC population consists of heterogeneous or homogeneous cells. In a previous study, we investigated the characteristics of hAEC isolated from four different regions of the amniotic membrane finding significant heterogeneity. The aim of this study was to evaluate the hepatic differentiation capability of hAEC isolated from these four regions. Human term placentae were collected after caesarean section and hAEC were isolated from four regions of the amniotic membrane (R1-R4, according to their relative distance from the umbilical cord) and treated in hepatic differentiation conditions for 14 days. hAEC-derived hepatocyte-like cells showed marked differences in the expression of hepatic markers: R4 showed higher levels of Albumin and Hepatocyte Nuclear Factor (HNF) 4α whereas R1 expressed higher Cytochrome P450 enzymes, both at the gene and protein level. These preliminary results suggest that hAEC isolated from R1 and R4 of the amniotic membrane are more prone to hepatic differentiation. Therefore, the use of hAEC from a specific region of the amniotic membrane should be taken into consideration as it could have an impact on the outcome of therapeutic applications. 相似文献
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In searching for differentially expressed genes in human uterine leiomyomas (ULs), suppression sub-tractive hybridization was used to construct an UL up-regulated library, which turned out to represent 88genes. After two rounds of screening by reverse Northern analysis, twenty genes were proved to be up-regulated, including seventeen known genes and three genes with unknown function. All these genes werefirstly associated with UL. Three genes with notable difference were selected for Northern confirmationOur results proved the authenticity of the twenty genes. One gene named Phospholipase A2 (PLA2) showedup-regulation in 4/6 of the patients and investigation of tissue distribution indicated that it had obviousexpression in prostate, testis, liver, heart and skeletal muscle. 相似文献
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Summary The presence of neurofilament (NF)-like and glial fibrillary acidic protein (GFAP)-like immunoreactivities was studied in sympathetic ganglia of adult rats and guinea pigs during normal conditions and after perturbation. In the superior cervical ganglion (SCG) of normal rats, many ganglion cells and nerve fibers show NF immunoreactivity. Some of these nerve fibers disappear after preganglionic decentralization of SCG; this indicates the presence of a mixture of preand postganglionic NF-positive nerves in the ganglion. Cuts in both preand postganglionic nerves result in a marked increase in GFAP immunoreactivity in SCG, whereas NF immunoreactivity increases in nerve cell bodies after preganglionic cuts. Only a few ganglion cells show NF immunoreactivity in the normal SCG of guinea pig. All intraganglionic NF-positive nerves are of preganglionic origin; decentralization abolishes NF immunoreactivity in these nerve fibers. The inferior mesenteric ganglion, the hypogastric nerves and colonic nerves in guinea pigs contain large numbers of strongly NF-immunoreactive nerve fibers.When the SCG of adult rat is grafted to the anterior eye chamber of adult rat recipients, both ganglionic cell bodies and nerve fibers, forming on the host iris from the grafted ganglion, are NF-positive. As only the perikarya of these neurons normally exhibit NF immunoreactivity, and the terminal iris arborizations are NF-negative, it appears that the grafting procedure causes NF immunoreactivity to become more widespread in growing SCG neurons. 相似文献
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In this paper, we describe the procedure of large-scale and efficient electrofusion for pronuclear transplantation in mouse eggs and the tolerance of the eggs for electric stimulus, assessed in vitro and in vivo development. The fusion chamber was arranged in parallel by dielectrodes (30-mm length, 1-mm width, and 2-mm height), and 0.3 M mannitol in distilled water was used as a fusion solution. The agglutination cleavage of enucleated eggs with karyoplast was easily orientated in parallel with electrodes by alternating current between 100 and 500 kHz at 2 and 10 V/mm. Immediately after the orientation, a direct current of 150 V/mm was given for 200 μsec twice and repeated three times to induce fusion of the enucleated eggs with karyoplast. More than five eggs, at least, can be submitted to electrofusion at the same time. The eggs that were not fused were treated again in the same manner. The proportion of eggs fused with karyoplast was increased by preincubation in M16 medium prior to submitting them to the electrofusion. When the eggs were incubated for 60 min, 80% of them were fused with karyoplast by the first electric treatment; in contrast, only 19% of the eggs were fused if they were submitted to electrofusion directly. It was found that between the CD-1 and F1 strains there was a difference in tolerance of the eggs to electric stimulus and that this was depend on the nuclei but not on cytoplasm. The proportion of development to blastocyst in the eggs fused with the pronuclear karyoplast derived from F1 (75 and 71%) was twice that of the eggs fused with the pronuclei derived from CD-1 strain (25 and 37%). After transfer to recipients, live young were obtained from both the eggs fused with karyoplast following one or two electrofusion exposures. 相似文献
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A comparative study on immunosuppressive effects of cyclosporin A and FK 506 on peripheral blood lymphocytes in dogs 总被引:1,自引:0,他引:1
Kyoichi Takaori Yoshinori Nio Kazutomo Inoue Thein Tun Manaba Fukumoto Tohru Hashida Masato Yasuhara Ryohei Hori Takayoshi Tobe 《Biotherapy》1992,4(2):129-137
Immunosuppressive effects of cyclosporin A (CsA) and FK 506 (FK) on peripheral blood lymphocytes were studied in dogs in respect to mixed lymphocyte reaction, proliferative responses to recombinant interleukin-2 (rIL-2), phytohemagglutinin (PHA) and concanavalin-A (Con-A); phenotypes of OKIa1, CD3, CD8 and surface IgM; cytotoxic activity against xenogeneic tumor cells. CsA (2.0 or 5.0 mg/kg, intravenously) or FK (0.16 mg/kg, intramuscularly) was given to mongrel dogs every morning for serial 21 days. The blood concentrations of CsA, measured as trough levels by fluorescence polarization method, ranged from 37 to 350 ng/ml in dogs administered at 2.0 mg/kg and from 170 to 894 ng/ml in dogs administered at 5.0 mg/kg during treatment, respectively. In dogs treated with FK at a dose of 0.16 mg/kg, the drug concentrations in the plasma during treatment ranged from 0.16 to 1.8 ng/ml. Mixed lymphocyte reaction and proliferative responses to rIL-2, PHA and Con-A, which were declined by CsA, were not affected by FK. In contrast, the proportion of OKIa1+ cells was not affected by CsA, whereas FK decreased the proportion of OKIa1+ cells progressively during the course of treatment. Cytotoxic activity was suppressed by both CsA and FK. These results possibly indicate that CsA and FK exert their immunosuppressive effects via different mechanisms. 相似文献
8.
Uterine biopsy in the mare on day 4 post-ovulation causes an acute inflammatory reaction which results in premature luteolysis. In this study, seven mares (4 to 6 years of age) were used in a switchback experimental design to test the hypothesis that in the mare parenterally administered PBZ will block luteolysis induced by uterine biopsy on day 4 post-ovulation. All mares were allowed two normal estrous cycles (range 18 to 24 days). On the first day of estrus of the third estrous cycle each mare was intravenously given 2 grams PBZ (treatment) or 10 ml 0.9% saline (control) daily until signs of estrus were exhibited. The day of ovulation (day 0) was determined by rectal palpation and subsequently verified by peripheral plasma progesterone concentrations. On day 4 following ovulation all mares were subjected to uterine biopsy, and subsequent estrus detection was performed daily using an andro-genized gelding. A total of 19 estrous cycles (ten for PBZ treatment and nine for controls) were evaluated. Mean number of days (+/-SE) from uterine biopsy to induced estrus was 5.00+/-0.16 for control cycles and was significantly different (P<0.025) when compared with 9.20+/-0.34 days for treatment cycles. Results of this study suggest that PBZ can block luteolysis in the mare induced by uterine biopsy on day 4 post-ovulation, possibly as a result of accumulating PBZ in acutely inflamed uterine tissue and inhibiting prostaglandin synthesis. 相似文献
9.
Location of the embryonic vesicle within the uterus of mares was recorded every. five minutes for two consecutive hours (25 location determinations per trial) in three experiments. In Experiment 1 (n=7), the number of location changes among nine uterine segments (three body segments and three segments for each horn) was greater (P<0.05) on Day 13 than on Day 10. The vesicle was located in the body more frequently (P<0.05) and tended (P<0.1) to move to a more caudal position more frequently on Day 10 than on Day 13. Fixation occurred on Day 15 in four of seven mares and on Day 16 in the remaining three mares. The number of location changes was not significantly different between two days prior to fixation and one day prior to fixation. In Experiment 2, the effect of clenbuterol, a B2 sympathomimetic blocker of uterine contractions, was studied on Days 12 or 13 of pregnancy. Location changes occurred less frequently (P<0.05) in treated mares (n=9) than in controls (n=10), indicating involvement of uterine contractions in the mobility of the embryonic vesicle. In Experiment 3, when the initial direction of location changes was caudal within a horn and cranial within the uterine body, the vesicle was more likely (P<0.05) to continue moving in the same direction than in the opposite direction. However, when the direction within a horn was cranial, the next location change was as likely to be in the opposite direction as in the same direction (not significantly different from equality). When the direction within the uterine body was caudal, the next location change was more likely (P<0.05) to be in the opposite direction. 相似文献
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The Drosophila melanogaster mutant fs(1)1304 is an ovary autonomous female sterile mutant that causes abnormal morphology of the egg. Vitellogenesis proceeds at an abnormally slow rate in homozygous females. We have used pole cell transplantation to construct germ line mosaics in order to determine whether the 1304 defect depends upon the genotype of the germ line cells (oocyte or nurse cells) or the somatic line (follicle cells). We have found that the germ line is the primary target tissue where the mutant gene is expressed. 相似文献