共查询到20条相似文献,搜索用时 15 毫秒
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This work was undertaken to compare the behavior of Friend erythroleukemia cells in a solenoid, where the magnetic field was 70 μT at 50 Hz (plus 45 μT DC of Earth) with that of the same cells in a magnetically shielded room, where the magnetic field was attenuated to 20 nT DC and 2.5 pT AC. The control laboratory magnetic field corresponded to 45 μT DC and a stray 50 Hz field below 0.2 μT. The culture growth cycle of cells maintained inside the solenoid was slightly accelerated compared with that of cells maintained outside the solenoid (P < .05). This stimulation probably depended on sensitivity of cell cycle to a magnetic field, because, inside the solenoid, the percentage of G1 cells slightly increased during the culture growth cycle, whereas that of S cells slightly decreased. Acceleration of growth was detected soon after exposure of the cultures to the solenoid field, and growth did not change further if the action of this field continued for a long time, accounting for adaptation. The solenoid field also caused a small increase of cell survival without influencing cell volume. By contrast, the culture growth cycle of cells maintained inside the magnetically shielded room was slightly decelerated compared with that of cells maintained outside the room (P < .05). The essential absence of any field inside the magnetically shielded room also caused a small increase of cell volume, whereas, during the culture growth cycle, the percentage of G1 cells decreased, and that of S cells increased. The majority of these events did not change in cells induced to differentiate hemoglobin through dimethylsulfoxide. Bioelectromagnetics 18:58–66, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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Marie Goepp Delphine Le Guennec Adrien Rossary Marie-Paule Vasson 《BioEssays : news and reviews in molecular, cellular and developmental biology》2020,42(9):1900116
This study shows that double thymidine block treatment efficiently arrests the EO771 cells in the S-phase without altering cell growth or survival. A long-term analysis of cell behavior, using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) staining, show synchronization to be stable and consistent over time. The EO771 cell line is a medullary breast-adenocarcinoma cell line isolated from a spontaneous murine mammary tumor, and can be used to generate murine tumor implantation models. Different biological (serum or amino acid deprivation), physical (elutriation, mitotic shake-off), or chemical (colchicine, nocodazole, thymidine) treatments are widely used for cell synchronization. Of the different methods tested, the double thymidine block is the most efficient for synchronization of murine EO771 cells if a large quantity of highly synchronized cells is recommended to study functional and biochemical events occurring in specific points of cell cycle progression. 相似文献
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Cornelia Speth Jörg T. Epplen Ilse Oberbäumer 《In vitro cellular & developmental biology. Animal》1991,27(8):646-650
Summary Oligonucleotide fingerprinting was applied to investigate the relatedness of several cell lines that were established between
1973 and 1977 from a teratocarcinoma. We were able to distinguish cell lines derived at different times. In addition, sublines
from one cell line (PYS-2) could be discriminated by using a combination of different probes. Therefore multilocus fingerprinting
with oligonucleotides is a useful method for monitoring changes in cell lines kept in culture for many generations.
This work was supported by the Deutsche Forschungsgemeinschaft (OB 66/2-1) and by the VW-Stiftung. 相似文献
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Kano J Ishiyama T Nakamura N Iijima T Morishita Y Noguchi M 《In vitro cellular & developmental biology. Animal》2003,39(10):440-448
The existence, origin, and bipotency of the hepatic stem cell (HeSC) have been investigated. However, the isolation and culture of HeSCs from adult liver tissue is not yet well established, and the mechanism by which HeSCs differentiate into mature cells remains unclear. On the other hand, the development of HeSC-isolating and -culturing methods and the in vitro clonal analysis of their mechanism of differentiation are required to enable clinical applications of regenerative medicine in the liver. For the purpose of providing HeSCs for these studies, we attempted to establish an HeSC line from a normal adult porcine liver using a unique culture system, a poly-D-lysine-coated culture dish with NAIR-1 medium (the PDL-NAIR-1 culture system). Moreover, we examined the differentiating capacity of HeSCs in vitro. We demonstrated that it was possible in the culture system that immature epithelial cells capable of proliferating grew selectively into aggregates and that two hepatic stem-like cell lines, PHeSC-A1 and PHeSC-A2, were established. The results from our data suggest that these hepatic stem-like cell lines were capable of self-renewing and differentiating into hepatocytes or biliary epithelial cells and show that the PDL-NAIR-1 culture system offers the immense advantage of isolating and culturing HeSCs from a normal adult liver. Furthermore, because of the ability to use a clonal analysis in vitro, these cell lines are useful for the investigation of various mechanisms in which HeSCs seem to participate and their application in the study of regenerative medicine in the liver. 相似文献
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精原干细胞(spermatogonial stem cells,SSCs)是位于睾丸曲细精管基膜上能自我更新和连续分化产生精子的最原始精原细胞,是雄性体内唯一能将遗传信息自然传至子代并可终生复制的双倍体细胞,对复杂的精子发生过程有着至关重要的作用。作为一个未分化细胞群体,SSCs在精子生成和物种进化所必需的基因传递中发挥作用。基于课题组多年的研究,该文较系统地评述了SSCs的生物学特性、分离富集、体外培养影响因素和移植技术等方面的进展,以期对雄性辅助生殖、细胞再生治疗、畜牧业生产等研究应用提供借鉴。 相似文献
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Ieharu Hishinuma Tetsuro Ishii Hiroyuki Watanabe Shiro Bannai 《In vitro cellular & developmental biology. Plant》1986,22(3):127-134
Summary Mouse lymphoma L1210 cells maintained in vitro at a high cell density for a certain time period adapted themselves to the
in vitro environment and were able to grow indefinitely. From these adapted cells, more than 30 clones were isolated. They
all had much higher activity to take up cystine than the original L1210 cells, supporting a previous view that the deficiency
of the cystine uptake limits the survival and growth of L1210 cells in vitro. The cystine uptake of one cloned cell line was
characterized. The enhanced uptake of cystine in these cells was mainly mediated by a Na+-independent, saturable system and was potently inhibited by glutamate and some other anionic amino acids, but less by aspartate.
Such activity of cystine uptake was not observed in the original L1210 cells. The results suggest that, upon adaptation in
vitro, L1210 cells acquire a new cystine transport activity necessary for survival and growth in vitro. 相似文献
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Young Seung Lee Jae‐Young Chung Sang Bong Jeon Ae‐Kyoung Lee Hyung‐Do Choi 《Bioelectromagnetics》2019,40(7):445-457
This paper proposes a novel in vitro exposure system operating at millimeter‐wave (mmWave) 28 GHz, one of the frequency bands under consideration for fifth generation (5G) communication. We employed the field uniformity concept along cross‐sectional observation planes at shorter distances from the radiation antenna for better efficiency and a small‐size system. A choke‐ring antenna was designed for this purpose in consideration of a wider beamwidth (BW) and a symmetric far‐field pattern across three principal planes. The permittivity of Dulbecco's modified Eagle's medium solution was measured to examine the specific absorption rate (SAR) of the skin cell layer inside a Petri dish model for a three‐dimensional (3D) cell culture in vitro experiment. The best deployment of Petri dishes, taking into account a geometrical field symmetry, was proposed. Local SAR values within the cell layer among the Petri dishes were determined with different polarization angles. It was determined that this polarization effect should be considered when the actual exposure and deployment were conducted. We finally proposed an in vitro exposure system based on the field uniformity including downward exposure from an antenna for 3D cell culture experiments. A small‐size chamber system was obtained, and the size was estimated using the planar near‐field chamber design rule. Bioelectromagnetics. 2019;40:445–457. © 2019 Bioelectromagnetics Society 相似文献
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Tonia Luca Edoardo Napoli Giovanna Privitera Nicol Musso Giuseppe Ruberto Sergio Castorina 《化学与生物多样性》2020,17(8)
Colon cancer is one of the most common human malignancies, and chemotherapy cannot yet prevent recurrence in all patients. Essential oils are phytocomplexes with antiproliferative properties. In this study, we elucidated the antiproliferative properties and the effect on cell cycle progression of Sicilian Salvia officinalis essential oil and its three main compounds, α‐thujone, 1,8‐cineole (eucalyptol) and camphor, on three human colon cancer cell lines. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography. Cell proliferation was evaluated by MTT assay, and the cell cycle distribution was determined by flow cytometry. Thirty‐four compounds were identified in the tested essential oil. Growth inhibition was observed after 72 h, with an impact on cell cycle progression and no effect on the viability of normal colonic epithelial cells. The study shows that S. officinalis essential oil and its three main components have an in vitro antiproliferative effect on colon cancer cells. 相似文献
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干细胞以其多潜能性和自我更新能力成为人类早期胚胎研究、干细胞治疗和组织工程修复中的主要细胞来源和种子细胞。但传统细胞研究方法难以提供干细胞生长和分化所需的复杂多层次的微环境,使研究结果与体内真实情况相差甚远,尽可能模拟和精确调控干细胞培养微环境,进而控制干细胞自我更新或分化命运,成干细胞研究的难点。微流控芯片可以更真实地模拟干细胞小生境(niche);实时可控的对单个干细胞加载剪切力和生长因子;其透明的装置可对细胞行为进行跟踪观察等研究细胞微环境中占有优势,从而受到越来越多干细胞研究者的关注。结合对微流控技术研究经验,对干细胞微环境构建所需条件进行了综述,总结了微流控在干细胞研究中所取得的成果,并展望了微流控技术在干细胞研究中的应用前景。 相似文献
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Atsushi Tsuboi Mieko Matsui Isamu Hayata Takehiko Tsuchiya 《In vitro cellular & developmental biology. Plant》1980,16(7):600-608
Summary The establishment of mouse tumor cell lines capable of proliferating in vivo and in suspension culture was undertaken. The
MM-46 tumor line, initiated from primary mammary carcinoma arising in a C3H/He mouse, was maintained for over 100 generations
in the peritoneal cavities of syngenic mice. At the 50th generation of the tumor suspension, cultures were initiated. The
established cell lines, designated TMT-1 and TMT-2, were characterized in vitro and in vivo. The morphological finding indicated
that TMT-1 and TMT-2 cells from mice closely resembled the MM-46 tumor cells. The oncogenic potential of the cultured cells
was comparable to that of the original ascites tumor. The population doubling time of TMT-1 and TMT-2 cell lines was about
12 hr in mice, whereas the population doubling time of both cell lines lengthened to 20 hr in suspension culture. The increase
of doubling time in culture was due to the prolongation of the G1 period. The cell lines, TMT-1 and TMT-2, whether from culture or mice, possessed colony forming ability in soft agar medium.
The colony forming ability of the cells decreased gradually through in vivo passages but it recovered upon recultivation of
the cells from mouse to culture. Chromosome analysis and cytotoxicity test by anti-MM antiserum indicated that TMT-1 and TMT-2
cell lines closely resembled and had been derived from MM-46 tumor line. Therefore, it is possible to assay cell survival
in vitro after in vivo experiments on these cells. 相似文献
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SYNOPSIS DNA synthesis of intracellular Trypanosoma cruzi amastigotes, following the infection of bovine embryo skeletal muscle (BESM) cells, was studied by autoradiography. After penetration, there was a prereplicative lag period (∼12 h) followed by a synchronous round of DNA synthesis which was found to be independent of parasite number/BESM cell and the host cell DNA synthesis cycle. Parasite reproduction occurred, for the first time, at ∼ 21 h postinfection. It was concluded that T. cruzi trypomastigotes are in the G1 /G, phase of their cell division cycle and that after penetration parasite reproduction occurs independent of events controlling host cell DNA synthesis and growth. The early synchronous growth of intracellular amastigotes should facilitate further studies on the biochemical events controlling trypomastigote-to-amastigote transformation and amastigote reproduction. A further application is envisaged for studies on the mode of action of drugs with trypanocidal activity. 相似文献
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体外培养条件下SCF、LIF与bFGF对昆明白小鼠精原干细胞增殖的影响 总被引:13,自引:2,他引:11
生长因子作为细胞体外培养和在体细胞生长及增殖必需的调节因子 ,一直被广泛的关注。业已证明干细胞因子(StemCellFactor,SCF)、白血病抑制因子 (leukaemiainhibitoryfactor,LIF)和碱性成纤维细胞生长因子 (BsaicFibroblastGrowthFactor,bFGF)具有刺激细胞增殖的作用[1~ 4] ,但大都是对单一因子进行研究。本实验探讨用这三种生长因子的不同组合观察对小鼠精原干细胞增殖的作用 ,以期定性和定量的探讨出体外培养初期三种因子对小鼠精原干细胞生长的影响 ,为小… 相似文献
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Charles M. McGrath Herbert D. Soule 《In vitro cellular & developmental biology. Plant》1984,20(8):652-662
Summary The concentration of Ca++ in culture media profoundly affected the growth and differentiation properties of normal human mammary epithelial cells in
short-term culture. In media where Ca++ was above 0.06 mM, longevity was limited to an average of three to four cell divisions. The extended growth fraction (those cells able, to
divide more than once) was only approximately 50% and diminished to zero quickly with time. Stationary cells inhibited from
dividing appeared differentiated in the formation of lipid vacuoles and accumulation of α-lactalbumin. Growth of stationary
cultures could be reinstituted in about half the cells, either by disruption and transfer or by a reduction in Ca++ to less than 0.08 mM.
The reduction of Ca++ to levels below 0.08 mM extended the longevity of normal cells to eight to nine divisions. The extended growth fraction was 100%. Under these conditions,
cells did not differentiate. The effects of Ca++ on growth and differentiation were specific (Mg++ and Mn++ variations were without effect) and reversible and in many respects resembled Ca++ effects on epidermal cells. One major difference is that the dual pathways of growth and differentiation in mammary cells
were controlled by glucocorticoid and insulin. Based on the kinetics of the reversible Ca++-induced coupling and uncoupling of proliferation and the program of differentiation, we propose that Ca++ may be an essential trigger for cell divisions that commit a mammary cell to differentiate progressively in a permissive
hormonal milieu.
This study was supported by grants NIH-CA18175 and CA36399 and an institutional grant from the United Foundation of Greater
Detroit. 相似文献
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Margaret J. Sekellick William J. Biggers Philip I. Marcus 《In vitro cellular & developmental biology. Plant》1990,26(10):997-1003
Summary When confluent monolayers of cells derived from chicken embryos of different gestational age were cultured for several days
without a medium change, a condition termed in vitro aging, the cells' developed an increased capacity to express the interferon
(IFN) system. The capacity to both produce IFN and to respond to its antiviral action were enhanced up to 1000- and 100-fold,
respectively. Remarkably, the programmed development of the IFN system in these cells seemed to continue virtually uninterrupted
after monodispersion of the cells and seeding at high cell density. Cells prepared from young embryos required more time to
develop the IFN system than cells from older embryos with the yield of IFN, and sensitivity to its action, related directly
to the total in ovo and in vitro age of the cells in culture. For example, essentially the same yields of IFN were obtained
from cell cultures made from 5-d-old embryos “aged” for 10 d in vitro, as were obtained from 10-d-old embryos whose cells
were aged in vitro for 5 d. In contrast, inducibility of 2′–5′ oligoadenylate synthetase by IFN and the induction of heat
shock genes by elevated temperature are not enhanced with in vitro aging. The programmed development of the IFN system that
starts in ovo seems to continue on schedule in vitro, making the development of the IFN system in chick embryo cells appear
as a time-dependent process.
This study was supported by the grant RO1 AI18381 from the national Institute of Allergy and Infectious Diseases, Bethesda,
MD, and benefited from services of the Cell Culture Facility of the Biotechnology Center at The Univeristy of Connecticut. 相似文献
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