共查询到20条相似文献，搜索用时 31 毫秒
1.
Elzbieta Jastrzebska Ilona Grabowska-Jadach Michal Chudy Artur Dybko Zbigniew Brzozka 《Biomicrofluidics》2012,6(4)
Cell migration is an important physiological process, which is involved in cancer metastasis. Therefore, the investigation of cell migration may lead to the development of novel therapeutic approaches. In this study, we have successfully developed a microsystem for culture of two cell types (non-malignant and carcinoma) and for analysis of cell migration dependence on distance between them. Finally, we studied quantitatively the influence of photodynamic therapy (PDT) procedures on the viability of pairs of non-malignant (MRC5 or Balb/3T3) and carcinoma (A549) cells coculture. The proposed geometry of the microsystem allowed for separate introduction of two cell lines and analysis of cells migration dependence on distance between the cells. We found that a length of connecting microchannel has an influence on cell migration and viability of non-malignant cells after PDT procedure. Summarizing, the developed microsystem can constitute a new tool for carrying out experiments, which offers a few functions: cell migration analysis, carcinoma and non-malignant cells coculture, and evaluation of PDT procedure in the various steps of cell migration. 相似文献
2.
Bishnubrata Patra Ying-Hua Chen Chien-Chung Peng Shiang-Chi Lin Chau-Hwang Lee Yi-Chung Tung 《Biomicrofluidics》2013,7(5)
Culture of cells as three-dimensional (3D) aggregates, named spheroids, possesses great potential to improve in vitro cell models for basic biomedical research. However, such cell spheroid models are often complicated, cumbersome, and expensive compared to conventional Petri-dish cell cultures. In this work, we developed a simple microfluidic device for cell spheroid formation, culture, and harvesting. Using this device, cells could form uniformly sized spheroids due to strong cell–cell interactions and the spatial confinement of microfluidic culture chambers. We demonstrated cell spheroid formation and culture in the designed devices using embryonic stem cells, carcinoma cells, and fibroblasts. We further scaled up the device capable of simultaneously forming and culturing 5000 spheroids in a single chip. Finally, we demonstrated harvesting of the cultured spheroids from the device with a simple setup. The harvested spheroids possess great integrity, and the cells can be exploited for further flow cytometry assays due to the ample cell numbers. 相似文献
3.
4.
Cell-microscale pattern surface interactions are crucial to understand many fundamental biological questions and develop regenerative medicine and tissue engineering approaches. In this work, we demonstrated a simple method to pattern PDMS surface by sacrificing poly vinyl pyrrolidone (PVP) electrospinning nanofibers and investigated the growth profile of cells on the modified patterned surfaces using stroma cells. The stromal cells were observed to exhibit good viability on this modified surface and the patterned surface with alignment nanofibers could promote cell migration. Furthermore, the modified PDMS surface was integrated with microfluidic channels to create the microscale spatial factor and was used to explore the cell migration and orientation under this microsystem. Both spatial factor and patterned surfaces were found to contribute to the complex cell orientation under the combined dual effects. This established method is simple, fast, and easy for use, demonstrating the potential of this microsystem for applications in addressing biological questions in complex environment. 相似文献
5.
Emad Y. Moawad 《Indian journal of clinical biochemistry : IJCB》2014,29(4):442-451
The purpose of this study is optimizing the l-arginine (l-Arg) doses on the basis of chemical structure in regional accessible tumor therapy to settle down a new protocol for the treatment of cancer. 3H-thymidine-based cell proliferation assay was performed in vitro on tumor cell lines of fibrosarcoma (FS), lymphosarcoma-ascitic and on normal cell line of NIH 3T3 after treatment with different concentrations of l-Arg in phosphate buffered saline (PBS). The cultures were harvested after 22 h and the incorporated radioactivity was counted to identify their histologic grades as described in earlier studies. In vivo therapy of murine tumors was conducted where FS cells injected subcutaneously at ventro-lateral position of mice. Various drug delivery schedules were injected into the centre of tumor base, once a day for 4 days. Tumor diameter and survivals were monitored where the day of sacrifice was considered for monitoring the survival period. By identifying the histologic grades of the treated cultures in vitro and in vivo by different concentrations of l-Arg, the corresponding energy of such concentrations were determined. An efficient model with a good fit (R2 = 0.98) was established to describe the energy yield by l-Arg dose. The equivalence between the tumor histologic grade and energy of the l-Arg dose delivered in saline (PBS) environment is the optimum condition for regional tumor therapy achieves higher survival rate. The selective cytotoxicity to tumor cells with minimal damage to normal cells by l-Arg due to its chemical structure suggests to be considered the most promising drug for regional therapy of the accessible tumors like breast cancers of early stage with no distant metastasis. 相似文献
6.
Monitoring cellular bioenergetic pathways provides the basis for a detailed understanding of the physiological state of a cell culture. Therefore, it is widely used as a tool amongst others in the field of in vitro toxicology. The resulting metabolic information allows for performing in vitro toxicology assays for assessing drug-induced toxicity. In this study, we demonstrate the value of a microsystem for the fully automated detection of drug-induced changes in cellular viability by continuous monitoring of the metabolic activity over several days. To this end, glucose consumption and lactate secretion of a hepatic tumor cell line were continuously measured using microfluidically addressed electrochemical sensors. Adapting enzyme-based electrochemical flat-plate sensors, originally designed for human whole-blood samples, to their use with cell culture medium supersedes the common manual and laborious colorimetric assays and off-line operated external measurement systems. The cells were exposed to different concentrations of the mitochondrial inhibitor rotenone and the cellular response was analyzed by detecting changes in the rates of the glucose and lactate metabolism. Thus, the system provides real-time information on drug-induced liver injury in vitro. 相似文献
7.
8.
Sara M. Bjork Staffan L. Sjostrom Helene Andersson-Svahn Haakan N. Joensson 《Biomicrofluidics》2015,9(4)
We investigate the impact of droplet culture conditions on cell metabolic state by determining key metabolite concentrations in S. cerevisiae cultures in different microfluidic droplet culture formats. Control of culture conditions is critical for single cell/clone screening in droplets, such as directed evolution of yeast, as cell metabolic state directly affects production yields from cell factories. Here, we analyze glucose, pyruvate, ethanol, and glycerol, central metabolites in yeast glucose dissimilation to establish culture formats for screening of respiring as well as fermenting yeast. Metabolite profiling provides a more nuanced estimate of cell state compared to proliferation studies alone. We show that the choice of droplet incubation format impacts cell proliferation and metabolite production. The standard syringe incubation of droplets exhibited metabolite profiles similar to oxygen limited cultures, whereas the metabolite profiles of cells cultured in the alternative wide tube droplet incubation format resemble those from aerobic culture. Furthermore, we demonstrate retained droplet stability and size in the new better oxygenated droplet incubation format. 相似文献
9.
Atherosclerotic lesions occur non-randomly at vascular niches in bends and bifurcations where fluid flow can be characterized as "disturbed" (low shear stress with both forward and retrograde flow). Endothelial cells (ECs) at these locations experience significantly lower average shear stress without change in the levels of pressure or strain, which affects the local balance in mechanical stresses. Common in vitro models of atherosclerosis focus primarily on shear stress without accounting for pressure and strain loading. To overcome this limitation, we used our microfluidic endothelial cell culture model (ECCM) to achieve accurate replication of pressure, strain, and shear stress waveforms associated with both normal flow seen in straight sections of arteries and disturbed flow seen in the abdominal aorta in the infrarenal segment at the wall distal to the inferior mesenteric artery (IMA), which is associated with high incidence of atherosclerotic lesion formation. Human aortic endothelial cells (HAECs) were cultured within the ECCM under both normal and disturbed flow and evaluated for cell shape, cytoskeletal alignment, endothelial barrier function, and inflammation using immunofluorescence microscopy and flow cytometry. Results clearly demonstrate quantifiable differences between cells cultured under disturbed flow conditions, which are cuboidal with short and randomly oriented actin microfilaments and show intermittent expression of β-Catenin and cells cultured under normal flow. However, in the absence of pro-inflammatory stimulation, the levels of expression of activation markers: intra cellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), platelet endothelial cell adhesion molecule-1 (PECAM-1), and vascular endothelial cell growth factor - receptor 2 (VEGF-R2) known to be involved in the initiation of plaque formation were only slightly higher in HAECs cultured under disturbed flow in comparison to cells cultured under normal flow. 相似文献
10.
BackgroundTo reduce costs associated with productivity of recombinant proteins in the biopharmaceutical industry, research has been focused on regulatory principals of growth and survival during the production phases of the cell culture. The main strategies involve the regulation of cell proliferation by the modulation of cell cycle control points (G1/S or G2/M) with mild hypothermia and the addition of sodium butyrate (NaBu). In this study, batch culture strategies were evaluated using CHO TF 70R cells producing the recombinant human tissue plasminogen activator (rh-tPA), to observe their individual and combined effect on the cellular physiological state and relevant kinetic parameters.ResultsNaBu addition has a negative effect on the mitochondrial membrane potential (∆ Ψm), the values of which are remarkably diminished in cultures exposed to this cytotoxic compound. This effect was not reflected in a loss of cell viability. NaBu and mild hypothermic conditions increased the doubling time in the cell cultures, suggesting that these strategies triggered a general slowing of each cell cycle phase in a different way. Finally, the individual and combined effect of NaBu and mild hypothermia produced an increase in the specific rh-tPA productivity in comparison to the control at 37°C without NaBu. Nevertheless, both strategies did not have a synergistic effect on the specific productivity.ConclusionsThe combination of NaBu addition and mild hypothermic condition causes an impact on physiological and metabolic state of CHO TF 70R cells, decreasing cell growth rate and improving glucose consumption efficiency. These results therefore provide a promising strategy to increase specific productivity of rh-tPA. 相似文献
11.
Serum glycoproteins were evaluated in oral squamous cell carcinoma patients treated with radiotherapy and also the effect
of vitamin E was studied. Cell surface glycoconjugates are important parameters in the detection of malignancy. Thus, the
objective of the present study is to evaluate the efficacy of vitamin E on glycoproteins in oral cavity cancer patients treated
with radiotherapy. The study includes 26 age and sex matched normal healthy individuals and 26 patients with squamous cell
carcinoma of oral cavity. These patients were divided into two groups, one for radiotherapy alone (at a dosage of 6000 cGy
in five fractions per week for a period of six weeks) and the other for radiotherapy plus vitamin E supplementation (at a
dosage of 400 IU / day of vitamin E) for the entire period of radiotherapy. Levels of hexose, hexosamine, fucose and sialic
acid were increased in oral squamous cell carcinoma patients and a significant decrease was observed in radiation treated
patients when compared to control. The levels of glycoconjugates were significantly decreased in radiation treated patients
supplemented with vitamin E. This measurement may be useful in assessing disease progression and identifying patients resistant
to therapy and a possible role of vitamin E on reduction in glycoconjugate levels of radiation treated oral squamous cell
carcinoma patients. 相似文献
12.
用单克隆抗体MC_3在福尔马林固定的48例大肠癌、31例癌变腺瘤、42例伴有不典型增生腺瘤、40例腺瘤、13例息肉以及48例正常肠粘膜组织切片上用免疫组化(PAP)法检测,结果MC_3相应抗原的表达阳性率分别为93.8％(45/48)、80.65％ (25/31)、47.62％ (20/42)、37.5％(15/40),其阳性率差异有非常显著性(P<0.001).48例正常肠粘膜均为阴性.MC_3在大肠癌组织中的反应程度与患者3年生存率有关,差异有显著意义(P<0.05).MC_3反应强度在高分化肠癌组与中～低分化肠癌组比较差异有显著意义(P<0.05).在绒毛状腺瘤、混合性腺瘤和管状腺瘤中MC_3相应抗原表达阳性率分别为71.4％(25/35)、60.0％(9/15)、41.3(26/63),差异有显著性(p<0.05).绒毛状腺瘤、混合性腺瘤和管状腺瘤其癌变率分别为45.7％(16/35)、13.3％(2/15)、20.6％(13/63),其癌变率比较差异有显著性(P<0.05). 相似文献
13.
Control of the 3D microenvironment for cultured cells is essential for understanding the complex relationships that biomolecular concentration gradients have on cellular growth, regeneration, and differentiation. This paper reports a microfluidic device for delivering gradients of soluble molecules to cells in an open reservoir without exposing the cells to flow. The cells are cultured on a polyester membrane that shields them from the flow that delivers the gradient. A novel "lid" design is implemented which prevents leakage from around the membrane without requiring sealing agents or adhesives. Once layers are molded, device fabrication can be performed within minutes while at room temperature. Surface gradients were characterized with epifluorescence microscopy; image analysis verified that sharp gradients (～33 μm wide) can be reproducibly generated. We show that heterogeneous laminar flow patterns of Orange and Green Cell Tracker (CT) applied beneath the membrane can be localized to cells cultured on the other side; concentration profile scans show the extent of CT diffusion parallel to the membrane's surface to be 10-20 μm. Our device is ideal for conventional cell culture because the cell culture surface is readily accessible to physical manipulation (e.g., micropipette access), the cell culture medium is in direct contact with the incubator atmosphere (i.e., no special protocols for ensuring proper equilibration of gas concentrations are required), and the cells are not subjected to flow-induced shear forces, which are advantageous attributes not commonly found in closed-channel microfluidic designs. 相似文献
14.
阐述了干细胞研究现状、发展趋势和应用前景 ,对如何推进我国干细胞工程学的发展提出了建议。 相似文献
15.
Rupprecht P Golé L Rieu JP Vézy C Ferrigno R Mertani HC Rivière C 《Biomicrofluidics》2012,6(1):14107-1410712
We have developed a method for studying cellular adhesion by using a custom-designed microfluidic device with parallel non-connected tapered channels. The design enables investigation of cellular responses to a large range of shear stress (ratio of 25) with a single input flow-rate. For each shear stress, a large number of cells are analyzed (500–1500 cells), providing statistically relevant data within a single experiment. Besides adhesion strength measurements, the microsystem presented in this paper enables in-depth analysis of cell detachment kinetics by real-time videomicroscopy. It offers the possibility to analyze adhesion-associated processes, such as migration or cell shape change, within the same experiment. To show the versatility of our device, we examined quantitatively cell adhesion by analyzing kinetics, adhesive strength and migration behaviour or cell shape modifications of the unicellular model cell organism Dictyostelium discoideum at 21 °C and of the human breast cancer cell line MDA-MB-231 at 37 °C. For both cell types, we found that the threshold stresses, which are necessary to detach the cells, follow lognormal distributions, and that the detachment process follows first order kinetics. In addition, for particular conditions’ cells are found to exhibit similar adhesion threshold stresses, but very different detachment kinetics, revealing the importance of dynamics analysis to fully describe cell adhesion. With its rapid implementation and potential for parallel sample processing, such microsystem offers a highly controllable platform for exploring cell adhesion characteristics in a large set of environmental conditions and cell types, and could have wide applications across cell biology, tissue engineering, and cell screening. 相似文献
16.
宫颈鳞状上皮癌变过程中细胞周期调节通路p14^ARF-MDM2-p53作用的研究 总被引：2，自引：0，他引：2
目的 探讨细胞周期调节p14ARF-MDM2-p53通路在宫颈上皮癌变过程中的作用.方法 采用免疫组化SP法检测18例正常宫颈上皮、48例宫颈上皮内瘤变(CIN)和23例宫颈鳞状细胞癌组织p14ARF、MDM2及p53蛋白的表达.结果 p14ARF蛋白表达阳性率在正常宫颈上皮、CIN和宫颈鳞癌组分别为28%、42%和78%,宫颈鳞癌组表达较正常上皮和CIN组升高(P＜0.05);MDM2蛋白表达阳性率在正常宫颈上皮、CIN和宫颈鳞癌组分别为0%、23%和43%,CIN和宫颈鳞癌组较正常宫颈上皮表达升高(P＜0.05);p53蛋白表达阳性率在正常宫颈上皮、CIN和宫颈鳞癌组分别为6%、31%和39%,CIN及宫颈鳞癌组表达水平较正常宫颈上皮升高(P＜0.05);统计分析未发现三种蛋白的表达存在显著相关性.结论 p14ARF-MDM2-p53细胞周期调节通路与宫颈癌发生发展有关并有望用于CIN及宫颈癌的诊断. 相似文献
17.
Valentina Vidranski Renata Laskaj Dubravka Sikiric Visnja Skerk 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(2):285-294
Background
Platelet satellitism is a phenomenon of unknown etiology of aggregating platelets around polymorphonuclear neutrophils and other blood cells which causes pseudothrombocytopenia, visible by microscopic examination of blood smears. It has been observed so far in about a hundred cases in the world.Case subject and methods
Our case involves a 73-year-old female patient with a urinary infection. Biochemical serum analysis (CRP, glucose, AST, ALT, ALP, GGT, bilirubin, sodium, potassium, chloride, urea, creatinine) and blood cell count were performed with standard methods on autoanalyzers. Serum protein fractions were examined by electrophoresis and urinalysis with standard methods on autoanalyzer together with microscopic examination of urine sediment. Erythrocyte sedimentation rate, blood culture and urine culture tests were performed with standard methods.Results
Due to typical pathological values for bacterial urinary infection, the patient was admitted to the hospital. Blood smear examination revealed phenomenon, which has persisted for three weeks after the disease has been cured. Blood smears with EDTA as an anticoagulant had platelet satellitism whereas the phenomenon was not observed in tubes with different anticoagulants (Na, Li-heparin) and capillary blood.Discussion
We hypothesize that satellitism was induced by some immunological mechanism through formation of antibodies which have mediated platelets binding to neutrophil membranes and vice versa. Unfortunately we were unable to determine the putative trigger for this phenomenon. To our knowledge this is the second case of platelet satellitism ever described in Croatia.Key words: blood platelets, thrombocytopenia, EDTA, urinary infection 相似文献18.
K. Hockemeyer C. Janetopoulos A. Terekhov W. Hofmeister A. Vilgelm Lino Costa J. P. Wikswo A. Richmond 《Biomicrofluidics》2014,8(4)
Stromal cells in the tumor microenvironment play a key role in the metastatic properties of a tumor. It is recognized that cancer-associated fibroblasts (CAFs) and endothelial cells secrete factors capable of influencing tumor cell migration into the blood or lymphatic vessels. We developed a microfluidic device that can be used to image the interactions between stromal cells and tumor cell spheroids in a three dimensional (3D) microenvironment while enabling external control of interstitial flow at an interface, which supports endothelial cells. The apparatus couples a 200-μm channel with a semicircular well to mimic the interface of a blood vessel with the stroma, and the design allows for visualization of the interactions of interstitial flow, endothelial cells, leukocytes, and fibroblasts with the tumor cells. We observed that normal tissue-associated fibroblasts (NAFs) contribute to the “single file” pattern of migration of tumor cells from the spheroid in the 3D microenvironment. In contrast, CAFs induce a rapid dispersion of tumor cells out of the spheroid with migration into the 3D matrix. Moreover, treatment of tumor spheroid cultures with the chemokine CXCL12 mimics the effect of the CAFs, resulting in similar patterns of dispersal of the tumor cells from the spheroid. Conversely, addition of CXCL12 to co-cultures of NAFs with tumor spheroids did not mimic the effects observed with CAF co-cultures, suggesting that NAFs produce factors that stabilize the tumor spheroids to reduce their migration in response to CXCL12. 相似文献
19.
A new strategy for magnetically manipulating and isolating adherent cells with extremely high post-collection purity and viability is reported. Micromolded magnetic elements (termed microrafts) were fabricated in an array format and used as culture surfaces and carriers for living, adherent cells. A poly(styrene-co-acrylic acid) polymer containing well dispersed magnetic nanoparticles was developed for creating the microstructures by molding. Nanoparticles of γFe(2)O(3) at concentrations up to 1% wt.∕wt. could be used to fabricate microrafts that were optically transparent, highly magnetic, biocompatible, and minimally fluorescent. To prevent cellular uptake of nanoparticles from the magnetic polymer, a poly(styrene-co-acrylic acid) layer lacking γFe(2)O(3) nanoparticles was placed over the initial magnetic microraft layer to prevent cellular uptake of the γFe(2)O(3) during culture. The microraft surface geometry and physical properties were altered by varying the polymer concentration or layering different polymers during fabrication. Cells plated on the magnetic microrafts were visualized using standard imaging techniques including brightfield, epifluorescence, and confocal microscopy. Magnetic microrafts possessing cells of interest were dislodged from the array and efficiently collected with an external magnet. To demonstrate the feasibility of cell isolation using the magnetic microrafts, a mixed population of wild-type cells and cells stably transfected with a fluorescent protein was plated onto an array. Microrafts possessing single, fluorescent cells were released from the array and magnetically collected. A post-sorting single-cell cloning rate of 92% and a purity of 100% were attained. 相似文献
20.
Ka?an Huysal Yasemin U. Budak Ayse Ulusoy Karaca Murat Aydos Serdar Kahvecio?lu Mehtap Bulut Murat Polat 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(2):211-217