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1.
Serum starvation induces binucleation in HeLa cells, but the effects of serum starvation on mitosis and the significance of binucleation remain unknown. We investigated the effect of serum starvation on mitosis and analyzed the growth of binucleated cells. The frequency of binucleation caused by cytokinesis failure in DMEM without FBS (0% medium) was higher than that in DMEM with FBS (10% medium). In 0% medium, the metaphase spindle location was off-center, and RhoA localization significantly lacked symmetry. The frequency of the extension of intercellular bridge with the midbody in 0% medium was significantly higher than that in 10% medium. Moreover, all mononucleated mitotic cells caused bipolar mitosis and produced only mononucleated daughter cells, but binucleated cells produced various nucleated cells by multipolar mitosis in 0% medium. These results suggest that serum starvation may have various effects on mitosis, and binucleated cells may be related to formation of aneuploidy.  相似文献   

2.
We developed a novel large-scale micropropagation pathway for date palm (Phoenix dactylifera L.) based on organogenesis. We obtained organogenic stems from shoot tip explants of the Moroccan date palm cultivar Najda, and investigated shoot proliferation from these organogenic stems in vitro on various media; Beauchesne medium (BM) and Murashige and Skoog medium (MS) at full-strength, half-strength, and one-third-strength, containing various concentrations (0, 0.25, 0.5, and 1 mg/L) of 2-naphthoxyacetic acid (NOAA) and kinetin. The optimal medium during the multiplication phase was half-strength Murashige and Skoog medium (MS/2) supplemented with 0.5 mg/L NOAA and 0.5 mg/L kinetin (23.5 morphologically superior shoots per explant, with low vitrification rates). For the shoot elongation phase, shoots were transferred to the same proliferation medium, or to MS or MS/2 media without plant growth regulators (PGRs). Shoots elongated rapidly and showed a high rate of root formation on media supplemented with PGRs. For example, on MS/2 medium containing 1 mg/L NOAA and 1 mg/L kinetin, the average shoot length was 15.1 cm, the average number of roots per shoot was 6.2, and their average length was 3.4 cm. On PGR-free media, shoots were shorter with wider and greener leaves, and had fewer roots. The plantlets were transferred to a greenhouse for acclimation. The survival rate after 2 months was related to the medium used during the elongation phase; >90 % of shoots that were cultured on PGR-free media survived, while there was a poor survival rate of shoots that had been cultured on media containing PGRs.  相似文献   

3.
A recent report showed that reversine treatment could induce murine myoblasts dedifferentiation into multipotent progenitor cells and inhibit proliferation of some tumors, and other reports showed that apoptosis of lung adenocarcinoma cells could be induced by aspirin. The aim of the present study was to evaluate the synergistic antitumor effects of reversine and aspirin on cervical cancer. The inhibition rate of reversine and aspirin on cervical cancer cell lines’ (HeLa and U14) was determined by MTT method, cell cycle of HeLa and U14 cells was analyzed by FACS, mitochondrial membrane potential of HeLa and U14 was detected using a JC-1 kit. HeLa and U14 colony formation was analyzed by soft agar colony formation assay. The expression of caspase-3, Bcl-2/Bax, cyclin D1 and p21 was detected by qRT-PCR and Western Blotting. Moreover, tumor weight and tumor volume was assessed using a murine model of cervical cancer with U14 cells subcutaneously (s.c.) administered into the neck, separately or combined with drug administration via the intraperitoneal (i.p.) route. The inhibition rate of cells in the combination group (10 μmol/L reversine, 10 mmol/L aspirin) increased significantly in comparison to that when the drugs were used alone (P < 0.05); moreover, this combination could synergistically inhibit the proliferation of five cervical cancer cell lines (HeLa, U14, Siha, Caski and C33A). In the therapeutic mouse model, tumor weight and tumor volume of cervical cancer bearing mice was more reduced when compared with the control agents (P < 0.05) in tumor-bearing mice. The combination of reversine and aspirin exerts synergistic growth inhibition and apoptosis induction on cervical cancers cells.  相似文献   

4.
This experiment aimed to study equine fibroblasts in culture analyzing and the cell cycle and viability of cells pre- and post-freezing. Skin fragments were obtained from 6 horses and cultured in DMEM high glucose + 10% FCS in 5% CO2 until the beginning of confluence. Two passages were performed before freezing. Cells subjected to serum starvation (0.5% FCS) were analyzed for viability and cell cycle at 24, 48, 72, 96, 120, 144 and 168 h of culture. For the confluent groups, cells were analyzed at the moment they achieved confluence. Cellular viability was assisted with Hoescht 33342 and propidium iodide. The analysis of apoptosis/necrosis and cell cycle was performed using a flow cytometer (FACS Calibur BD®) after staining the cells with annexin V and propidium iodide. Both optical microscopy and flow cytometry confirmed that cellular viability was similar for serum starvation and confluent groups (average 84%). Similarly, both methods were efficient to synchronize the cell cycle before freezing. However, after thawing, serum starvation, for more than 24 h, was superior to culture for synchronizing cells in G0/G1 (69% × 90%). The results of this experiment indicate that equine fibroblasts can be efficiently cultured after thawing.  相似文献   

5.
In order to develop conservation protocols for Campanula incurva, the geographical information systems (GIS) were used to unveil its ecological requirements; this facilitated the selection of substrates and of appropriate temperatures for cultivation and guided propagation experiments and acclimatization. Seed germination was tested under (i) dark, (ii) 16-h photoperiod, (iii) immersion in 400 ppm gibberellic acid (GA3) followed by incubation at dark, and (iv) immersion in 400 ppm GA3 followed by incubation at 16-h photoperiod (all at 21 ± 1°C). Dormancy was not detected. Germination exceeded 85% in 10 days. Shoot tips were established in vitro in Murashige and Skoog (MS) medium with 1 μM 6-benzyladenine (BA) and 0.1 μM indole-3-butyric acid (IBA). The effect of 1–8 μM BA and 1–8 μM kinetin on shoot proliferation was studied. Moreover, 8 μM BA was combined with 0, 1, 5, and 10 μM IBA to investigate effects of cytokinin/auxin. The highest number of microshoots/explant (4.03) was obtained with 8 μM BA. Microshoots were transferred to half strength MS and full strength MS media with 0, 0.5, 1, 5, and 10 μM IBA to evaluate their root induction ability. Half strength MS medium with 5 μM IBA resulted in 100% rooting (16.80 average number of roots/microshoot). Plantlets produced were successfully acclimatized.  相似文献   

6.
An efficient hairy root induction system for an important endangered medicinal plant, Dracocephalum kotschyi, was developed through Agrobacterium rhizogenes-mediated transformation by modifying the co-cultivation medium using five bacterial strains, A4, ATCC15834, LBA9402, MSU440, and A13 (MAFF-02-10266). A drastic increase in transformation frequency was observed when a Murashige and Skoog medium lacking NH4NO3 KH2PO4, KNO3 and CaCl2 was used, resulting in hairy root induction frequencies of 52.3 %, 69.6 %, 48.6 %, 89.0 %, and 80.0 % by A4, A13, LBA9402, MSU440, and ATCC15834 strains, respectively. For shoot induction, hairy roots and unorganized tumors induced by strain ATCC15834 were placed on an MS media supplemented with 0.1, 0.25, 0.5, and 1 mg/l BA plus 0.1 mg/l NAA. The high frequency of shoot regeneration and number of shoot were obtained in the medium containing 0.25 mg/l BA and 0.1 mg/l NAA. Root induction occurred from the base of regenerated shoots on the MS medium supplemented with 0.5 mg/l IBA after 10 days.  相似文献   

7.
A chemically defined platform basal medium and feed media were developed using a single Chinese hamster ovary (CHO) cell line that produces a monoclonal antibody (mAb). Cell line A, which showed a peak viable cell density of 5.9 × 106 cells/mL and a final mAb titer of 0.5 g/L in batch culture, was selected for the platform media development. Stoichiometrically balanced feed media were developed using glucose as an indicator of cell metabolism to determine the feed rates of all other nutrients. A fed-batch culture of cell line A using the platform fed-batch medium yielded a 6.4 g/L mAb titer, which was 12-fold higher than that of the batch culture. To examine the applicability of the platform basal medium and feed media, three other cell lines (A16, B, and C) that produce mAbs were cultured using the platform fed-batch medium, and they yielded mAb titers of 8.4, 3.3, and 6.2 g/L, respectively. The peak viable cell densities of the three cell lines ranged from 1.3 × 107 to 1.8 × 107 cells/mL. These results show that the nutritionally balanced fed-batch medium and feeds worked well for other cell lines. During the medium development, we found that choline limitation caused a lower cell viability, a lower mAb titer, a higher mAb aggregate content, and a higher mannose-5 content. The optimal choline chloride to glucose ratio for the CHO cell fed-batch culture was determined. Our platform basal medium and feed media will shorten the medium-development time for mAb-producing cell lines.  相似文献   

8.
The efficacy of hepatocellular carcinoma (HCC) treatment is very low because of the high percentage of recurrence and resistance to anticancer agents. Hepatic cancer stem cells (HCSCs) are considered the origin of such recurrence and resistance. Our aim was to evaluate the stemness of doxorubicin and 5-fluorouracil resistant hepatic cancer cells and establish the new method to isolate the HCSCs from primary cultured HCC tumors. HCC biopsies were used to establish primary cultures. Then, primary cells were selected for HCSCs by culture in medium supplemented with doxorubicin (0, 0.1, 0.25, 0.5 or 1 μg/mL), 5-fluorouracil (0, 0.1, 0.25, 0.5 or 1 μg/mL) or their combination. Selection was confirmed by detection of HCSC markers such as CD133, CD13, CD90, and the side population was identified by rhodamine 123 efflux. The cell population with the strongest expression of these markers was used to evaluate the cell cycle, gene expression profile, tumor sphere formation, marker protein expression, and in vivo tumorigenesis. Selective culture of primary cells in medium supplemented with 0.5 μg/mL doxorubicin and 1 μg/mL 5-fluorouracil selected cancer cells with the highest stemness properties. Selected cells strongly expressed CD13, CD133, CD90, and CD326, efflux rhodamine 123 and formed tumor spheres in suspension. Moreover, selected cells were induced to differentiate into cells with high expression of CD19 and AFP (alpha-fetoprotein), and importantly, could form tumors in NOD/SCID mice upon injection of 1 × 105 cells/mouse. Selective culture with doxorubicin and 5-fluorouracil will enrich HCSCs, is an easy method to obtain HCSCs that can be used to develop better therapeutic strategies for patients with HCC, and particularly HCSC-targeting therapy.  相似文献   

9.
Cell behaviours such as proliferation and attachment can be affected by the length of pre-incubation period of the scaffolds in the culture medium for long term. The aim of this study was to investigate the long term pre-incubation of 3D silk fibroin scaffolds in complete culture medium on cell attachment and proliferation. After the preparation of silk fibroin scaffolds by the technique of freeze drying, the scaffolds were pre-incubated in complete culture medium for 2 d, 6 d or 10 d before apical papilla stem cells (SCAP) seeding. Modifications of the scaffold surface and wettability were examined by FE-SEM and water contact angle, respectively. Results showed a decrease both in roughness and water contact angle as pre-incubation time increases. DNA measurement after 18 h and 10 d cell seeding showed a significant increase of DNA concentration which represents better attachment and proliferation with pre-incubation time increase. Qualitative examination, live&dead assay or H&E staining method after 30 h and 10 d cell seeding respectively, indicated that pre-incubation of scaffolds has time dependent effect on cell proliferation and attachment. This suggests that improvement of cell attachment and proliferation may be mediated by differences in the amount of wettability (decreased water contact angle) after exposure of scaffold to culture medium for long term which, in turn, causes more protein adsorption in the surface of silk fibroin scaffold (decreased roughness).  相似文献   

10.
Advances in cell biology depend, partly, on the development of new cell lines and culture methods. Our research focused on a fibroblast-like cell line, “KSG,” which is derived from scorpionfish fin tissue (Sebastiscus marmoratus). Cells were grown in Leibovitz’s L-15 medium with 10% fetal bovine serum following standard procedures. The optimum growth temperatures for these lines ranged from 15°C to 25°C. All cells survived storage for at least 3 yr at ?80°C. Subsequently, they were continuously cultured until the 78th generation without evident changes in their morphology. Moreover, we were able to culture KSG cells in the absence of fetal bovine serum in a culture medium containing the fish serum “SeaGrow.” Optimum SeaGrow concentrations for these cells ranged from 5% to 20%. The growth rate of KSG cells decreased when the concentration of SeaGrow was reduced to 1%. However, this decrease could be partially reversed by adding 0.5% “Hy-Fish.” In addition, the inclusion of Hy-Fish improved cell adhesion. KSG cells that were cultured in serum-free culture media containing 0.5% and 1% Hy-Fish had been added and were able to survive at low densities. Furthermore, we successfully transfected this cell line with a commercial plasmid vector coding a fluorescent protein using the cationic lipid. Finally, the analyses of cell behavior under hydrostatic pressure showed that some pressures (10 MPa) helped the cells to proliferate more.  相似文献   

11.
Gordonia polyisoprenivorans CCT7137, exopolysaccharide-producing bacterium, was isolated from groundwater contaminated with leachate in a former municipal landfill site (São Paulo, Brazil). The strain was submitted to starvation in phosphate-buffered saline solution for 56 days so as to evaluate its behavior regarding cuturability and cell morphology. As a response to starvation, G. polyisoprenivorans CCT7137 presented reduction in viable cell count, cell size and cell shape alteration. The initial number of viable cells was 1.51 × 107 c.f.u. ml. After 7 days of starvation culturability dropped to 13.70% (2.07 × 106 c.f.u/ml) and, after 56 days, to 3.25% (4.93 × 105 c.f.u/ml). It was also observed that after 7 days of starvation the cell size presented an average reduction in the values of length, length/width ratio, volume and area of 50, 58, 40 and 42%, respectively. The length/width ratio showed a change of shape from rod to coccobacillus. Changes in cell dimensions and distribution of cell into classes were not significant after day 7 of starvation. The results obtained show that it is not necessary for the strain to starve for more than a week to obtain G. polyisoprenivorans CCT7137 size- reduced cells. The results also indicate the potential for its starved forms to be used in future tests in porous medium to study the production of exopolysaccharide in situ.  相似文献   

12.
In the present study a simple and efficient somatic embryogenesis system was developed from leaf explants of Lycopersicon esculentum L. The protocol has been developed by using plant growth regulators and seaweed extracts a natural biostimulant. The leaf sections were initially cultured on to leaf embryogenic callus induction medium fortified with various concentration and combinations of 2,4-dichlorophenoxy acetic acid (0.2–1.0 mg L?1), picloram (0.2–1.0 mg L?1), and kinetin (0.1–0.5 mg L?1). The best responding concentration in induction of friable embryogenic callus was tested for the proliferation. The friable cultures were detached from the mother culture and inoculated in three different media supplemented with plant growth regulators, plus 0–25 % Caulerpa scalpelliformis or 0–25 % Gracilaria corticata extracts for embryo development. A twofold increase in maturation and germination of somatic embryos was observed in the media containing seaweed extracts (MSMG2 and MSMG3) than the control (MSMG1). The plantlets transferred from plant growth chamber to greenhouse conditions exhibited higher survival rate (90 %) than directly shifted plantlets.  相似文献   

13.
Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 106 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to be more beneficial for treating breast cancer than donkey milk.  相似文献   

14.
An improved protocol for plant regeneration via somatic embryogenesis was developed using mature macaw palm (Acrocomia aculeata) zygotic embryos as initial explant. For induction of the embryogenic callus (EC), two basic media (BM) were tested consisting of Murashige and Skoog and Eeuwens (Y3) salts with 30 g L?1 sucrose, 0.5 g L?1 glutamine and 2.5 g L?1 Phytagel. The 3,6-dichloro-2-methoxybenzoic acid (dicamba), 4-amino-3,5,6-trichloro-picolinic acid (picloram) and 2,4-dichlorophenoxyacetic acid (2,4-D) auxins were added to the culture media at concentrations of 0, 1.5 or 3.0 mg L?1. After 240 days, the embryogenic calli were transferred to the respective BM media with auxin concentrations reduced to 0.5 or 1.0 mg L?1 in order to differentiate the somatic embryos (SEs). Plant regeneration was performed on the BM media without growth regulators. Embryogenic calli were observed after 180 days of culture and in all treatments with auxin. The Y3 medium showed the best EC formation results (60.8 %). These calli showed yellowish coloration, compact consistency and nodular aspect. After 60 days in differentiation medium, SEs were verified in different stages of development. Histological analysis showed that the SEs were formed from a nodular EC. The SEs generally presented unicellular origin with suspensor formation, and at the end of development, bipolar embryos were observed. The plant regeneration frequency reached levels up to 31.9 % when using induction medium consisting of Y3 associated to 1.5 mg L?1 of 2,4-D and the subsequent auxin reduction to 0.5 mg L?1 in the differentiation stage. Regenerated plants showed normal development, with root and aerial part growth.  相似文献   

15.
Spodoptera exigua Se301 cells have been successfully adapted to two different commercial serum-free media (SFM; Ex-Cell 420 and Serum-Free Insect Medium-1) by gradually reducing the 10 %-added serum-containing medium content from 100 % to 0 % (v/v) in suspended cultures. Both direct adaptation to a serum-free medium and cell growth in the absence of protective additives against fluid dynamic stress [polyvinyl pyrrolidone and polyvinyl alcohol] and disaggregation [dextran sulfate] proved impossible. Cells grew reproducibly in both SFMs once the serum had been completely removed, although the use of Ex-Cell 420 resulted in higher growth rates and cell densities. Turbulence was sufficiently high to reduce growth rates and final cell densities at the highest Reynolds number investigated, although no clear influence of agitation was observed on virus productivity. Both attached and suspended Se301 cell cultures were successfully infected with the SeMNPV baculovirus. Cells adapted to different conditions (attached or suspended culture, serum-containing or serum-free medium) showed different occlusion bodies productivities at the two multiplicities of infection assayed (0.1 and 0.5).  相似文献   

16.
Chaperones assist in the correct folding of newly synthesised proteins in the endoplasmic reticulum (ER) of cells, this being essential for the translocation of protein molecules to specific subcellular compartments, extracellular matrix or to biological fluids. The biosynthesis of some ER chaperones is regulated by glucose. They are named "glucose-regulated proteins" (GRPs). The function of some GRPs depends on oxygen, a subgroup named "oxygen-regulated proteins" (ORPs). The biosynthesis of ORPs is induced by deprivation of glucose or oxygen. Exposure of HeLa cells to glucose starvation induces the biosynthesis of various GRPs including ORP 150. The expression of ORP 150 is regulated by the concentration of glucose in the culture medium, being induced by a shortage and repressed by a presence of glucose. We have shown that both glucose starvation and transfection of cells with siRNA (specific to ORP 150 mRNA) evoke similar, but quantitatively different, effects. The cells grown for 72 h in a 4.5 mg/ml glucose-containing medium demonstrated low apoptosis (3.7%) whereas in a 0.5 mg/ml glucose-containing medium the apoptosis was increased to 10%. The effect of transfection on apoptosis was distinctly higher with almost 22% of apoptotic cells detected in 72 h cultures. One may conclude that ORP 150 reduces the pro-apoptotic effects of glucose starvation. Such a hypothesis is supported by the observation that the transfection procedure makes HeLa cells resistant to the regulatory effect of glucose on ORP 150 production. The transfected cells do not respond to glucose starvation with an overexpression of ORP 150. It is apparent from our experiments that ORP 150 plays an important role in adaptation of cells to the shortage of glucose and reduces the pro-apoptotic effect of glucose starvation.  相似文献   

17.
Since antizyme (AZ) is known to inhibit cell proliferation and to increase apoptosis, the question arises as to whether these effects occur independently of polyamines. Intestinal epithelial cells (IEC-6) were grown in control medium and medium containing 5 mM difluoromethylornithine (DFMO) to inhibit ODC, DFMO + 5 µM spermidine (SPD), DFMO + 5 µM spermine (SPM), or DFMO + 10 µM putrescine (PUT) for 4 days and various parameters of growth were measured along with AZ levels. Cell counts were significantly decreased and mean doubling times were significantly increased by DFMO. Putrescine restored growth in the presence of DFMO. However, both SPD and SPM when added with DFMO caused a much greater inhibition of growth than did DFMO alone, and both of these polyamines caused a dramatic increase in AZ. The addition of SPD or SPM to media containing DFMO + PUT significantly inhibited growth and caused a significant increase in AZ. IEC-6 cells transfected with AZ-siRNA grew more than twice as rapidly as either control cells or those incubated with DFMO, indicating that removal of AZ increases growth in cells in which polyamine synthesis is inhibited as well as in control cells. In a separate experiment, the addition of SPD increased AZ levels and inhibited growth of cells incubated with DFMO by 50 %. The addition of 10 mM asparagine (ASN) prevented the increase in AZ and restored growth to control levels. These results show that cell growth in the presence or absence of ODC activity and in the presence or absence of polyamines depends only on the levels of AZ. Therefore, the effects of AZ on cell growth are independent of polyamines.  相似文献   

18.
Umbilical cord (UC) is a rich source of rapidly proliferating mesenchymal stem cells (MSCs) that are easily cultured on a large-scale. Clinical applications of UC–MSCs include graft-versus-host disease, and diabetes mellitus types 1 and 2. UC–MSCs should be isolated and proliferated according to good manufacturing practice (GMP) with animal component-free medium, quality assurance, and quality control for their use in clinical applications. This study developed a GMP standard protocol for UC-MSC isolation and culture. UC blood and UC were collected from the same donors. Blood vasculature was removed from UC. UC blood was used as a source of activated platelet rich plasma (aPRP). Small fragments (1–2 mm2) of UC membrane and Wharton’s jelly were cut and cultured in DMEM/F12 medium containing 1 % antibiotic–antimycotic, aPRP (2.5, 5, 7.5 and 10 %) at 37 °C in 5 % CO2. The MSC properties of UC–MSCs at passage 5 such as osteoblast, chondroblast and adipocyte differentiation, and markers including CD13, CD14, CD29, CD34, CD44, CD45, CD73, CD90, CD105, and HLA-DR were confirmed. UC–MSCs also were analyzed for karyotype, expression of tumorigenesis related genes, cell cycle, doubling time as well as in vivo tumor formation in NOD/SCID mice. Control cells consisted of UC–MSCs cultured in DMEM/F12 plus 1 % antibiotic–antimycotic, and 10 % fetal bovine serum (FBS). All UC-MSC (n = 30) samples were successfully cultured in medium containing 7.5 and 10 % aPRP, 92 % of samples grew in 5.0 % aPRP, 86 % of samples in 2.5 % aPRP, and 72 % grew in 10 % FBS. UC–MSCs in these four groups exhibited similar marker profiles. Moreover, the proliferation rates in medium with PRP, especially 7.5 and 10 %, were significantly quicker compared with 2.5 and 5 % aPRP or 10 % FBS. These cells maintained a normal karyotype for 15 sub-cultures, and differentiated into osteoblasts, chondroblasts, and adipocytes. The analysis of pluripotent cell markers showed UC–MSCs maintained the expression of the oncogenes Nanog and Oct4 after long term culture but failed to transfer tumors in NOD/SCID mice. Replacing FBS with aPRP in the culture medium for UC tissues allowed the successful isolation of UC–MSCs that satisfy the minimum standards for clinical applications.  相似文献   

19.
A simple method has been developed for clonal propagation of mature trees of Tecomella undulata (Sm.) Seem, a medicinally important deciduous timber tree of hot arid regions, via multiple shoot proliferation from axillary buds after examining the role of season influences and physico–chemical conditions on micropropagation. Spring season (March–April) was the best period for contamination free establishment of explants and maximum sprouting of healthy axillary buds. Shoots proliferated directly from the explant nodes cultured on Murashige and Skoog’s medium containing cytokinins, BAP supporting better growth compared to kinetin during shoot induction as well as multiplication phase. Cytokinin concentration influenced the bud induction frequency and optimal response of 2.6 buds per explant was achieved in 86.66% explants on media supplemented with 10 µM BAP. Stunted shoot buds with excessive callus were observed when cytokinin concentration was increased beyond optimal levels. Ascorbic acid (50 mg/l), arginine and citric acid (25 mg/l each) were added to proliferation and multiplication media for reducing callus proliferation and better shoot growth. Among the media (B5, MS, NN, WPM and SH) tested, SH was best for shoot multiplication. Shoot cultures were multiplied by regular subculture of axillary shoots on SH medium containing 5.0 µM each of BAP and kinetin. Shoots produced roots when cultured on ½× SH medium + 10 μM IBA. Regenerated plantlets were successfully transferred to field after hardening and acclimatization. Genetic homogeneity of tissue culture raised plants was confirmed by generation of monomorphic DNA fragments with Start codon targeted and intersimple sequence repeat (ISSR) markers.  相似文献   

20.
The present work evaluated biomass productivity, carbon dioxide fixation rate, and biochemical composition of two microalgal species, Phaeodactylum tricornutum (Bacillariophyta) and Tetradesmus obliquus (Chlorophyta), cultivated indoors in high-technology photobioreactors (HT-PBR) and outdoors both in pilot ponds and low-technology photobioreactors in a greenhouse in southern Italy. Microalgae were grown in standard media, under nitrogen starvation, and in two liquid digestates obtained from anaerobic digestion of agro-zootechnical and vegetable biomass. P. tricornutum, cultivated in semi-continuous mode in indoor HT-PBRs with standard medium, showed a biomass productivity of 21.0?±?2.3 g m?2 d?1. Applying nitrogen starvation, the lipid productivity increased from 2.3 up to 4.5?±?0.5 g m?2 d?1, with a 24 % decrease of biomass productivity. For T. obliquus, a biomass productivity of 9.1?±?0.9 g m?2 d?1 in indoor HT-PBR was obtained using standard medium. Applying liquid digestates as fertilizers in open ponds, T. obliquus gave a biomass productivity (10.8?±?2.0 g m?2 d?1) not statistically different from complete medium such as P. tricornutum (6.5?±?2.2 g m?2 d?1). The biochemical data showed that the fatty acid composition of the microalgal biomass was affected by the different cultivation conditions for both microalgae. In conclusion, it was found that the microalgal productivity in standard medium was about doubled in HT-PBR compared to open ponds for P. tricornutum and was about 20 % higher for T. obliquus.  相似文献   

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