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1.
《Cell reports》2020,30(3):807-819.e4
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2.
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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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
6.
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
7.
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
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Jerry R. Colca Nirmala Kotagal Paul E. Lacy Michael L. McDaniel 《生物化学与生物物理学报:生物膜》1983,729(2):176-184
The properties of active or ATP-dependent calcium transport by islet-cell endoplasmic reticulum and plasma membrane-enriched subcellular fractions were directly compared. These studies indicate that the active calcium transport systems of the two membranes are fundamentally distinct. In contrast to calcium uptake by the endoplasmic reticulum-enriched fraction, calcium uptake by islet-cell plasma membrane-enriched vesicles exhibited a different pH optimum, was not sustained by oxalate, and showed an approximate 30-fold greater affinity for ionized calcium. A similar difference in affinity for calcium was exhibited by the Ca2+-stimulated ATPase activities which are associated with these islet-cell subcellular fractions. Consistent with the effects of calmodulin on calcium transport, calmodulin stimulated Ca2+-ATPase in the plasma membranes, but did not increase calcium-stimulated ATPase activity in the endoplasmic reticulum membranes. The physiological significance of the differences observed in calcium transport by the endoplasmic reticulum and plasma membrane fractions relative to the regulation of insulin secretion by the islets of Langerhans is discussed. 相似文献
10.
Yumiko Ushio Naoki Yamamoto Antonio Sanchez-Bueno Ryotaro Yoshida 《Microbiology and immunology》1996,40(7):489-498
After an i.p. transplantation of an allogeneic tumor (Meth A) to C57BL/6 mice, a macrophage (MΦ)-rich, non-T, non-NK cell population is induced as the major infiltrate and cytotoxic cells. We here evaluated the role of the MΦs in the rejection of allografted Meth A cells and characterized the MΦs in comparison with other well-known MΦs. At all time intervals after transplantation, the highest cytotoxic activities against Meth A tumor were obtained with the MΦ-rich population. In addition, the lymphocyte-rich population had a significant but low cytotoxic activity, whereas two other population types, granulocytes and large granular cells, were inactive. When the MΦ-rich or the T cell-depleted MΦ-rich population was i.p. transplanted simultaneously with Meth A cells into untreated C57BL/6 mice, the tumor cells were rejected without growth. After specific elimination of MΦs by in vivo application of dichloromethylene diphosphonate-containing liposomes, the cytotoxic activity against Meth A cells was hardly induced at the transplantation site of Meth A cells and the allografted Meth A tumor continued to grow, indicating that a type of MΦ is the effector cell essential for the rejection. In contrast to other well-known MΦs, the cytotoxic activity against Meth A cells was cell-to-cell contact dependent and soluble factor (e.g., NO and TNF-α) independent. Moreover, the cytotoxic activity of the MΦs (H-2b) against 51Cr-labeled Meth A (H-2d) cells was inhibited by the addition of unlabeled H-2d, but not H-2a, H-2k or H-2b, lymphoblasts as well as Meth A cells, implying the specific interaction of the MΦs with H-2d cells. 相似文献