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Clothier, Richard H. "Book Review: Culture of Animals Cells: Manual of Basic Technique — Third Edition". Alternatives to Laboratory Animals 23, n. 1 (gennaio 1995): 161. http://dx.doi.org/10.1177/026119299502300121.
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Hulme, Lesley. "Book Review: Culture of Animal Cells: A Manual of Basic Technique— 2Nd Edition". Alternatives to Laboratory Animals 16, n. 1 (settembre 1988): 97. http://dx.doi.org/10.1177/026119298801600119.
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Braylan, Raul C., e Elaine Kay Jordan. "Rapid and Simple Procedure For Isolation and Concentration Of Human Megakaryocytes From Marrow Aspirates". Blood 122, n. 21 (15 novembre 2013): 5269. http://dx.doi.org/10.1182/blood.v122.21.5269.5269.
Testo completoAbstract (sommario):
Abstract Background Numerical and morphologic abnormalities of megakaryocytes (MKs) are present in a variety of primary or secondary bone marrow (BM) disorders such as myeloproliferative neoplasms, myelodysplastic syndromes or ITP. Currently, these changes are assessed exclusively on microscopic preparations of marrow aspirates and biopsies and are used as criteria for disease diagnosis, classification and therapy monitoring despite the inherent subjectivity of microscopic evaluations. In contrast to other cells, adequate studies of freshly isolated MKs have proven difficult because of the relative rarity of these cells in the BM (∼0.05% of total nucleated cells) and separation techniques such as density gradients, magnetic beads, centrifugal elutriation or fluorescence activated cell sorting are labor-intensive, time-consuming or costly. The primary means for studying MKs is based on the isolation of progenitors primed with cytokines to differentiate in culture. While extremely valuable, these techniques are not directly translatable to the routine clinical arena for assessing MK pathology in human BM. Mature marrow MKs are large, polyploid cells whose size distribution overlaps minimally with that of all other marrow cells. This distinct size threshold is a discriminatory parameter for MK isolation. Thus, we developed a simple and inexpensive manual mesh filtration method for separation of MKs that allows a rapid and easy, size-based concentration and purification of these cells. Methods We examined 15 discarded anonymized BM aspirate samples suitable for our analysis. These samples were from patients with a variety of hematologic disorders originally submitted to our laboratory for evaluation. Sample age ranged from 1-4 days (mean 1.5 days). Samples were diluted with heparin/albumin-containing buffered saline solution. The cell suspensions were first filtered through a 70µm filter to remove large BM stromal particles and then twice (by gravity) through 9mm-diameter wetted 8 µm nylon filters placed in a simple plastic holder. This filtration procedure allowed the retention of MKs and removal of smaller cells. The MK-rich suspension was collected by rinsing and flushing the filters with the buffered solution. On average, the procedure only lasted 15 minutes. The pre-filtered, 8 µm filter-retained, and effluent cell suspensions collected were stained with an FITC-anti CD61 or PE-anti CD41a antibody [Becton Dickinson (BD)] to label MKs, concurrently with the cell permeable DNA-binding DRAQ5 (Cell Signaling Technology) to identify all nucleated cells. Final cell viability was assessed by C12Resazurin (Molecular probes). Cell analysis was performed by flow cytometry (FCM) using a CANTO II flow cytometer (BD). Absolute MK enumeration was performed using the Flow Cytometry Absolute Count Standard beads (Bangs). MK enrichment efficiency was expressed as the percentage of MKs of all nucleated cells determined by FCM. No cell lysing, fixation or centrifugation was used at any step of the MK separation procedure. Results The median (range) volume of the BM aspirate samples used in this study was 0.54 (0.24-1.99) mL. MKs were identified by FCM on the basis of their large size, expression of platelet-associated antigens and DNA ploidy levels. The median (range) MK recovery was 31 (14-100) % of the original number of MKs and the yield was 9,882 (1,519-49,921) MKs per mL of BM aspirate. The median (range) fraction of MKs among all nucleated cells after filtration was 39 (14-68) %, representing a 904 (439-3029)-fold MK enrichment. The MK viability after filtration was near 100%. Conclusions This simple, gentle, rapid and inexpensive isolation and concentration method results in a MK recovery and purification that is comparable or better than other more elaborate techniques. Despite the inherent heterogeneity of the samples used, we obtained a reasonably good recovery of MKs per mL of marrow aspirate and more than 900-fold median MK concentration. The yield and level of purification of freshly isolated MKs obtained by this simple procedure may be useful in studies of a variety of primary or secondary marrow disorders. In particular, it should facilitate the application of analytical methods such as flow cytometry or in situ hybridization, and even be useful for biochemical or molecular testing that require adequate cell representation and purity. Disclosures: No relevant conflicts of interest to declare.
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Hidayat, Nurul, Mega Novia Putri e Ronal Kurniawan. "Nannochloropsis sp phytoplankton culture technique laboratory scale". South East Asian Marine Sciences Journal 1, n. 2 (15 marzo 2024): 73–76. http://dx.doi.org/10.61761/seamas.1.2.73-76.
Testo completoAbstract (sommario):
Nannochloropsis sp is a phytoplankton often used in marine fish hatchery activities as feed for the mass production of rotifers, and its availability is very much needed for rearing marine fish larvae. This activity aims to study pure culture techniques for Nannochloropsis sp on a laboratory scale. The method used is a literature study method and a direct practical method regarding Nannochloropsis sp phytoplankton culture techniques laboratory scale and conducted interviews with employees at the BPBL Batam Phytoplankton Live Food Production Unit Laboratory. Based on observations, it was found that the peak growth or optimum cell density of Nannochloropsis sp. occurred on the sixth day in a 1000 mL Erlenmeyer, namely 60.95 - 62.10 million cells/mL with an initial density of 10.15 - 10.55 million cells/mL and in a 2000 mL Erlenmeyer, namely 58.75 - 60, 25 million cells/mL with an initial density of 8.25 – 8.45 million cells/mL.
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Lewis, Jennifer R., Mark S. Kotur, Omar Butt, Sumant Kulcarni, Alyssa A. Riley, Nick Ferrell, Kathryn D. Sullivan e Mauro Ferrari. "Biotechnology Apprenticeship for Secondary-Level Students: Teaching Advanced Cell Culture Techniques for Research". Cell Biology Education 1, n. 1 (marzo 2002): 26–42. http://dx.doi.org/10.1187/cbe.02-02-0003.
Testo completoAbstract (sommario):
The purpose of this article is to discuss small-group apprenticeships (SGAs) as a method to instruct cell culture techniques to high school participants. The study aimed to teach cell culture practices and to introduce advanced imaging techniques to solve various biomedical engineering problems. Participants designed and completed experiments using both flow cytometry and laser scanning cytometry during the 1-month summer apprenticeship. In addition to effectively and efficiently teaching cell biology laboratory techniques, this course design provided an opportunity for research training, career exploration, and mentoring. Students participated in active research projects, working with a skilled interdisciplinary team of researchers in a large research institution with access to state-of-the-art instrumentation. The instructors, composed of graduate students, laboratory managers, and principal investigators, worked well together to present a real and worthwhile research experience. The students enjoyed learning cell culture techniques while contributing to active research projects. The institution's researchers were equally enthusiastic to instruct and serve as mentors. In this article, we clarify and illuminate the value of small-group laboratory apprenticeships to the institution and the students by presenting the results and experiences of seven middle and high school participants and their instructors.
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Bleotu, Coralia, Carmen Diaconu, Mihaela Chivu, Irina Alexiu, Simona Ruta e Costin Cernescu. "Evaluation of TV cell line viral susceptibility using conventional cell culture techniques". Open Medicine 1, n. 1 (1 marzo 2006): 12–22. http://dx.doi.org/10.2478/s11536-006-0007-x.
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AbstractDespite the fact that a lot of methods have been developed for rapid virus detection, classic cell culture is still “the golden standard”. The range of viruses that can be isolated and cultured in cell line systems is often limited by the susceptibility of cells to support viral replication. Since the primary cell culture, the best cellular system available to support replication of a large number of viruses, is very expensive and diffcult to obtain, cell lines, which are easier to manipulate, are commonly used for virus growth and isolation.In two previous papers we described the TV cell line initiated by our team from a laryngeal tumor, which harbors human papillomavirus (HPV) gene sequences. In this paper we analyze its capacity to support virus replication. Depending on the virus, different cytopathic effects were produced. Comparison of viral effect observed on this cell line with the effect obtained on other cell lines has been performed. This cell line might be used in the clinical virology laboratory for virus isolation.
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Ciapetti, Gabriela, Elisabetta Cenni, Daniela Cavedagna, Loredana Pratelli e Arturo Pizzoferrato. "Cell Culture Methods to Evaluate the Biocompatibility of Implant Materials". Alternatives to Laboratory Animals 20, n. 1 (gennaio 1992): 52–60. http://dx.doi.org/10.1177/026119299202000107.
Testo completoAbstract (sommario):
Cell culture techniques are usually used in the field of biomaterials research and development in order to detect toxic components. Morphological assays are the most widely used methods and give the very first information about the biological compatibility of materials. Cell function assays give more quantitative data, but the comparison of data between different laboratories is difficult. Some of the cell culture methods that are used for biocompatibility studies are described briefly here, and results from our laboratory are reported. Despite some inherent limitations of the cell culture techniques, they are an accurate and reliable method of predicting the biological compatibility of materials to be implanted in vivo.
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Marion, Rebecca E., Grant E. Gardner e Lisa D. Parks. "Multiweek cell culture project for use in upper-level biology laboratories". Advances in Physiology Education 36, n. 2 (giugno 2012): 154–57. http://dx.doi.org/10.1152/advan.00080.2011.
Testo completoAbstract (sommario):
This article describes a laboratory protocol for a multiweek project piloted in a new upper-level biology laboratory (BIO 426) using cell culture techniques. Human embryonic kidney-293 cells were used, and several culture media and supplements were identified for students to design their own experiments. Treatments included amino acids, EGF, caffeine, epinephrine, heavy metals, and FBS. Students researched primary literature to determine their experimental variables, made their own solutions, and treated their cells over a period of 2 wk. Before this, a sterile technique laboratory was developed to teach students how to work with the cells and minimize contamination. Students designed their experiments, mixed their solutions, seeded their cells, and treated them with their control and experimental media. Students had the choice of manipulating a number of variables, including incubation times, exposure to treatment media, and temperature. At the end of the experiment, students observed the effects of their treatment, harvested and dyed their cells, counted relative cell numbers in control and treatment flasks, and determined the ratio of living to dead cells using a hemocytometer. At the conclusion of the experiment, students presented their findings in a poster presentation. This laboratory can be expanded or adapted to include additional cell lines and treatments. The ability to design and implement their own experiments has been shown to increase student engagement in the biology-related laboratory activities as well as develop the critical thinking skills needed for independent research.
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Shyam, Rohin, L. Reddy e Arunkumar Palaniappan. "Fabrication and Characterization Techniques of In Vitro 3D Tissue Models". International Journal of Molecular Sciences 24, n. 3 (18 gennaio 2023): 1912. http://dx.doi.org/10.3390/ijms24031912.
Testo completoAbstract (sommario):
The culturing of cells in the laboratory under controlled conditions has always been crucial for the advancement of scientific research. Cell-based assays have played an important role in providing simple, fast, accurate, and cost-effective methods in drug discovery, disease modeling, and tissue engineering while mitigating reliance on cost-intensive and ethically challenging animal studies. The techniques involved in culturing cells are critical as results are based on cellular response to drugs, cellular cues, external stimuli, and human physiology. In order to establish in vitro cultures, cells are either isolated from normal or diseased tissue and allowed to grow in two or three dimensions. Two-dimensional (2D) cell culture methods involve the proliferation of cells on flat rigid surfaces resulting in a monolayer culture, while in three-dimensional (3D) cell cultures, the additional dimension provides a more accurate representation of the tissue milieu. In this review, we discuss the various methods involved in the development of 3D cell culture systems emphasizing the differences between 2D and 3D systems and methods involved in the recapitulation of the organ-specific 3D microenvironment. In addition, we discuss the latest developments in 3D tissue model fabrication techniques, microfluidics-based organ-on-a-chip, and imaging as a characterization technique for 3D tissue models.
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Malovrh, Tadej, e Peter Hostnik. "Diagnostics procedures in rabies". Veterinarski glasnik 59, n. 1-2 (2005): 99–105. http://dx.doi.org/10.2298/vetgl0502099m.
Testo completoAbstract (sommario):
Rabies is a major zoonosis for which diagnostic techniques can only be performed in the laboratory. Laboratory techniques are preferably oriented on tissue removed from the cranium: hippocampus (Ammon's horn), cerebellum and the medulla oblongata or tissue liquids. Clinical observation may only lead to a suspicion of rabies. The only way to perform a reliable diagnosis of the disease is to identify the virus or some of its specific components using laboratory tests such as histological identification of characteristic cell lesions, immunochemical identification of rabies virus antigen and virus isolation. Serological tests are rarely used in epidemiological surveys but much more frequently in control of the vaccination programs (e.g. oral vaccination). Most commonly used serological tests are the virus neutralization test on cell culture (FAVN), virus neutralization in mice and ELISA.
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Tahir, Sonia, Saadia Chaudhary e Tahir Naeem. "Antimicrobial Resistance in Carbapenem resistance Pseudomonas". Pakistan Journal of Medical and Health Sciences 15, n. 9 (30 settembre 2021): 2280–81. http://dx.doi.org/10.53350/pjmhs211592280.
Testo completoAbstract (sommario):
Aim: To figure out the antimicrobial sensitivity effect of multidrug resistant Pseudomonas aeruginosa obtained from several type of clinical specimens. Study setting: Department of Microbiology and Resource laboratory, University of Health Sciences Lahore. Methods: A sum total of 53 isolates of multi-resistant Pseudomonas aeruginosa were selected from Jinnah hospital Lahore during the period of 1st January 2016 to 2nd February 2017. Nutrient agar slants were used for the transportation of resistant strains. In accordance with the CLSI manuals re-confirmation and processing of the strains were accomplished. The sub culturing and incubation was done on culture media such as MacConkey and blood agar at room temperature for 1 day. Standard confirmation of isolates under went by the graded morphological, cultural and biochemical techniques. In order to achieve this, Gram staining, culture media such as blood, oxidase test, motility test were executed. Results: The resistance pattern of Pseudomonas aeruginosa against antibiotics was as follows: Meropenem 53(100%), 51(96%) to piperacillin–tazobactam, 49(92%) to ceftazidime, 43(81%) to amikacin, 41(77%) showed resistance to aztreonam, 48(91%) to quinolones as shown in figure. Almost all the Pseudomonas aeruginosa were resistant to aztreonam except for 23% (n=12 isolates). Colistin was predominant as the major strength of treatment for Pseudomonas aeruginosa with sensitivity of 48(91%). Keywords: Disk-diffusion, Carbapenem, McFarland.
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MacLean, Lorna M., Mark Ariyanayagam, Lalitha Sastry, Christy Paterson, Manu De Rycker e Alan H. Fairlamb. "Validation of Trypanosoma cruzi inactivation techniques for laboratory use". PLOS ONE 19, n. 4 (18 aprile 2024): e0300021. http://dx.doi.org/10.1371/journal.pone.0300021.
Testo completoAbstract (sommario):
Trypanosoma cruzi (T. cruzi) is the causative agent of Chagas’ disease, a parasitic infection responsible for significant morbidity and mortality in Latin America. The current treatments have many serious drawbacks and new drugs are urgently required. In the UK, T. cruzi is classified by the Advisory Committee on Dangerous Pathogens (ACDP) as a Hazard Group 3 organism and strict safety practices must be adhered to when handling this pathogen in the laboratory. Validated inactivation techniques are required for safe T. cruzi waste disposal and removal from Containment Level 3 (CL3) facilities for storage, transportation and experimental analysis. Here we assess three T. cruzi. inactivation methods. These include three freeze-thaw cycles, chemical inactivation with Virkon disinfectant, and air drying on Whatman FTA cards (A, B, C, Elute) and on a Mitra microsampling device. After each treatment parasite growth was monitored for 4–6 weeks by microscopic examination. Three freeze-thaw cycles were sufficient to inactivate all T. cruzi CLBrener Luc life cycle stages and Silvio x10/7 A1 large epimastigote cell pellets up to two grams wet weight. Virkon treatment for one hour inactivated T. cruzi Silvio x10/7 subclone A1 and CLBrener Luc both in whole blood and cell culture medium when incubated at a final concentration of 2.5% Virkon, or at ≥1% Virkon when in tenfold excess of sample volume. Air drying also inactivated T. cruzi CLBrener Luc spiked blood when dried on FTA A, B or Elute cards for ≥30 minutes and on a Mitra Microsampler for two hours. However, T. cruzi CLBrener Luc were not inactivated on FTA C cards when dried for up to two hours. These experimentally confirmed conditions provide three validated T. cruzi inactivation methods which can be applied to other related ACDP Hazard Group 2–3 kinetoplastid parasites.
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Toranzos, Gary A., Abdiel J. Alvarez e Elizabeth A. Dvorsky. "Application of the Polymerase Chain Reaction Technique to the Detection of Pathogens in Water". Water Science and Technology 27, n. 3-4 (1 febbraio 1993): 207–10. http://dx.doi.org/10.2166/wst.1993.0347.
Testo completoAbstract (sommario):
Enteric pathogens may be present in fecally contaminated waters at extremely low concentrations. In addition, these pathogens may be injured when exposed to the environment and may not be able to grow in laboratory culture media or such media may simply not exist for their progagation in the laboratory. It is paramount thus to use techniques which do not depend on culture techniques for the detection of these pathogens and that allow for the detection of single-cell concentrations. The polymerase chain reaction (PCR) technique has been shown to be an excellent and sensitive means of detecting pathogens in waters. Membrane filtration has been combined with PCR and DNA hybridization techniques to be able to detect the DNA equivalent of one single cell in large volumes of water. In addition, this combination of methods allows for the amplification of different target genes fiat may be present in the sample, since the membrane can be subjected to repeated amplification reactions under different conditions. A Most Probable Number PGR was developed which allows for the quantification of gene copy number and thus permits extrapolation to estimate the number of bacterial cells in the original sample.
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Leland, Diane S., e Christine C. Ginocchio. "Role of Cell Culture for Virus Detection in the Age of Technology". Clinical Microbiology Reviews 20, n. 1 (gennaio 2007): 49–78. http://dx.doi.org/10.1128/cmr.00002-06.
Testo completoAbstract (sommario):
SUMMARY Viral disease diagnosis has traditionally relied on the isolation of viral pathogens in cell cultures. Although this approach is often slow and requires considerable technical expertise, it has been regarded for decades as the “gold standard” for the laboratory diagnosis of viral disease. With the development of nonculture methods for the rapid detection of viral antigens and/or nucleic acids, the usefulness of viral culture has been questioned. This review describes advances in cell culture-based viral diagnostic products and techniques, including the use of newer cell culture formats, cryopreserved cell cultures, centrifugation-enhanced inoculation, precytopathogenic effect detection, cocultivated cell cultures, and transgenic cell lines. All of these contribute to more efficient and less technically demanding viral detection in cell culture. Although most laboratories combine various culture and nonculture approaches to optimize viral disease diagnosis, virus isolation in cell culture remains a useful approach, especially when a viable isolate is needed, if viable and nonviable virus must be differentiated, when infection is not characteristic of any single virus (i.e., when testing for only one virus is not sufficient), and when available culture-based methods can provide a result in a more timely fashion than molecular methods.
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Gradišnik, Lidija, Roman Bošnjak, Gorazd Bunc, Janez Ravnik, Tina Maver e Tomaž Velnar. "Neurosurgical Approaches to Brain Tissue Harvesting for the Establishment of Cell Cultures in Neural Experimental Cell Models". Materials 14, n. 22 (13 novembre 2021): 6857. http://dx.doi.org/10.3390/ma14226857.
Testo completoAbstract (sommario):
In recent decades, cell biology has made rapid progress. Cell isolation and cultivation techniques, supported by modern laboratory procedures and experimental capabilities, provide a wide range of opportunities for in vitro research to study physiological and pathophysiological processes in health and disease. They can also be used very efficiently for the analysis of biomaterials. Before a new biomaterial is ready for implantation into tissues and widespread use in clinical practice, it must be extensively tested. Experimental cell models, which are a suitable testing ground and the first line of empirical exploration of new biomaterials, must contain suitable cells that form the basis of biomaterial testing. To isolate a stable and suitable cell culture, many steps are required. The first and one of the most important steps is the collection of donor tissue, usually during a surgical procedure. Thus, the collection is the foundation for the success of cell isolation. This article explains the sources and neurosurgical procedures for obtaining brain tissue samples for cell isolation techniques, which are essential for biomaterial testing procedures.
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Tanyuksel, Mehmet, e William A. Petri. "Laboratory Diagnosis of Amebiasis". Clinical Microbiology Reviews 16, n. 4 (ottobre 2003): 713–29. http://dx.doi.org/10.1128/cmr.16.4.713-729.2003.
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SUMMARY The detection of Entamoeba histolytica, the causative agent of amebiasis, is an important goal of the clinical microbiology laboratory. To assess the scope of E. histolytica infection, it is necessary to utilize accurate diagnostic tools. As more is discovered about the molecular and cell biology of E. histolytica, there is great potential for further understanding the pathogenesis of amebiasis. Molecular biology-based diagnosis may become the technique of choice in the future because establishment of these protozoa in culture is still not a routine clinical laboratory process. In all cases, combination of serologic tests with detection of the parasite (by antigen detection or PCR) offers the best approach to diagnosis, while PCR techniques remain impractical in many developing country settings. The detection of amebic markers in serum in patients with amebic colitis and liver abscess appears promising but is still only a research tool. On the other hand, stool antigen detection tests offer a practical, sensitive, and specific way for the clinical laboratory to detect intestinal E. histolytica. All the current tests suffer from the fact that the antigens detected are denatured by fixation of the stool specimen, limiting testing to fresh or frozen samples.
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Craig, B., L. Hawkey e A. LeFurgey. "Techniques for cryoultramicrotomy of propane jet frozen biological samples". Proceedings, annual meeting, Electron Microscopy Society of America 44 (agosto 1986): 260–61. http://dx.doi.org/10.1017/s042482010014292x.
Testo completoAbstract (sommario):
Ultra-rapid freezing followed by cryoultramicrotomy is essential for the preservation of diffusible elements in situ within cells prior to scanning transmission electron microscopy and quantitative energy dispersive x-ray microanalysis. For cells or tissue fragments in suspension and for monolayer cell cultures, propane jet freezing provides cooling rates greater than 30,000°C/sec with regions up to 40μm in thickness free of significant ice crystal formation. While this method of freezing has frequently been applied prior to freeze fracture or freeze substitution, it has not been widely utilized prior to cryoultramicrotomy and subsequent x-ray microanalytical studies. This report describes methods devised in our laboratory for cryosectioning of propane jet frozen kidney proximal tubule suspensions and cultured embryonic chick heart cells, in particular a new technique for mounting frozen suspension specimens for sectioning. The techniques utilize the same specimen supports and sample holders as those used for freeze fracture and freeze substitution and should be generally applicable to any cell suspension or culture preparation.
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Chernov, Vladimir E., Margarita O. Sokolova, Anastasia K. Ivanova, Aleksandra S. Buntovskaya, Elena I. Koreshova, Aleksandra E. Trandina, Anna S. Frumkina e Olga N. Harkevich. "Iniciation and cultivation of multipotent mesenchimal human umbilical stroma cells in a laboratory experiment". Russian Military Medical Academy Reports 41, n. 3 (19 ottobre 2022): 283–91. http://dx.doi.org/10.17816/rmmar104363.
Testo completoAbstract (sommario):
BACKGROUND: Whartons jelly of the human umbilical cord is one of the sources of multipotent mesenchymal stromal cells. The cell population obtained from the postpartum biomaterial is characterized by high proliferative and regenerative properties. Isolation of a culture of multipotent mesenchymal stromal cells from the umbilical cord does not pose a threat to the health and life of the donor.
AIM: Optimization of the technique for isolating a reproducible population of multipotent mesenchymal stromal cells from Whartons jelly is an urgent task in biomedicine, which can accelerate the process of obtaining donor cells for cell therapy and tissue engineering.
MATERIALS AND METHODS: In the study, the main techniques and methods for isolating the culture of umbilical cord stroma cells were tested, the cultivation process was optimized to increase its efficiency and reduce the time of growth of cell biomass. The effect of the components of the nutrient medium on the cells obtained from Whartons jelly of the human umbilical cord was studied. Currently, there is no universal composition of the growth medium; in various studies, nutrient media from different manufacturers are used, which differ in composition. The most discussed issue is the selection of serum, which is part of the nutrient medium.
RESULTS: In the work, a comparative evaluation of five different sera was carried out. It has been shown that the most stable physiological parameters are observed in cell suspension samples with the addition of FBS (SKPK, Russia) and FBS (Capricorn, USA) sera. A study of the effect of hypoxia on cell culture in combination with the most effective sera showed that hypoxic stress acts as an activator of primary cell proliferation. The assessment of the effect of serum and hypoxia on cell culture was carried out visually using microscopy, assessment of changes in cell morphology during cultivation, and the results of testing the action of sera by the intensity of respiration of free and immobilized cells under the action of inhibitors.
CONCLUSION: As a result of the experiments, the influence of the type of serum on the initiation of cell expansion from primary explants and further cell proliferation in vitro was established. Hypoxia during exposure of primary explants enhances the expansion of cells from tissue fragments of Whartons jelly tissue.
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Vermorken, A. J. M. "Culture Techniques and Potential Research Applications of Human Hair Follicle Cells In Vitro". Alternatives to Laboratory Animals 13, n. 1 (settembre 1985): 8–37. http://dx.doi.org/10.1177/026119298501300104.
Testo completoAbstract (sommario):
Since 1980, when human hair follicle cells were cultured in vitro for the first time, a whole series of techniques have been developed that render hair follicle keratinocytes as easy to handle in culture as fibroblasts. As a consequence, one can conclude that the need for a method providing for the routine cultivation of easily obtainable human primary epithelial cells has now been met, and it may be expected that more and more workers will use hair follicle keratinocytes for studies that specifically require human epithelial cells. The ease of culture and the ready availability of material may encourage workers to consider human hair follicle cell culture before either animal models or cultures of cells derived from invasive skin biopsies.
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Rausch, Finja, Franziska Tanneberger, Ahmed Abd El Wahed e Uwe Truyen. "Validation of the efficacy of air purifiers using molecular techniques". PLOS ONE 18, n. 1 (9 gennaio 2023): e0280243. http://dx.doi.org/10.1371/journal.pone.0280243.
Testo completoAbstract (sommario):
The importance of air purifiers has increased in recent years, especially with the “coronavirus disease 2019” pandemic. The efficacy of air purifiers is usually determined under laboratory conditions before widespread application. The standard procedure for testing depends on virus cultivation and titration on cell culture. This, however, requires several days to deliver results. The aim of this study was to establish a rapid molecular assay which can differentiate between intact infectious and distorted non-infectious virus particles. Feline Coronavirus was selected as model for screening. First the samples were pretreated with enzymes (universal nuclease and RNase cocktail enzyme mixture) or viability dye (propidium monoazide) to eliminate any free nucleic acids. The ribonucleic acid (RNA) from intact virus was released via magnetic beads-based extraction, then the amount of the RNA was determined using real-time reverse transcription polymerase chain reaction (RT-PCR) or reverse transcription recombinase-aided amplification (RT-RAA). All results were compared to the infectivity assay based on the calculation of the 50% tissue culture infectious dose (TCID50). The nuclease has eliminated 100% of the free Feline Coronavirus RNA, while propidium monoazide underperformed (2.3-fold decrease in free RNA). Both RT-RAA and real-time RT-PCR produced similar results to the infectivity assay on cell culture with limit of detection of 102 TCID50/mL. Two UV-C air purifiers with prosperities of 100% inactivation of the viruses were used to validate the established procedure. Both real-time RT-PCR and RT-RAA were able to differentiate between intact virus particles and free RNA. To conclude, this study revealed a promising rapid method to validate the efficacy of air purifiers by combining enzymatic pretreatment and molecular assays.
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Gallentine, Summer, e Heather Powell. "21 Decreasing Preparation Time of Full-thickness Engineered Constructs: Seeding Dermal Allografts with Non-cultured Keratinocytes". Journal of Burn Care & Research 43, Supplement_1 (23 marzo 2022): S17. http://dx.doi.org/10.1093/jbcr/irac012.025.
Testo completoAbstract (sommario):
Abstract Introduction Early wound closure reduces risk of infection and fluid loss, which can reduce mortality and decrease length of hospital stay. The most common challenge associated with rapid wound closure in patients with large, full-thickness (FT) burns is lack of available donor skin. Tissue engineering can generate significant amounts of tissue for grafting but requires specialized facilities and up to three weeks of culture, substantially increasing time to closure. Off-the-shelf technologies that do not require ex vivo culture of cells represent a major advance in wound care. Point-of-care cell spray technology isolated using an autologous cell harvesting device (ACHD) allows for immediate application of a cell suspension to the wound bed, eliminating specialized laboratory equipment and culture of skin cells. The goal of this project was to assess the ability of freshly isolated skin cells harvested using ACHD or traditional laboratory techniques to regenerate epithelium on engineered dermal tissue, in an effort to decrease time required for preparation of FT engineered skin. Methods Dermal allografts were made by seeding collagen scaffolds with human dermal fibroblasts. Human surgical discard tissue was collected with IRB approval. Split-thickness skin (0.008”) was harvested from the discard tissue and cells were isolated using ACHD or via standard laboratory procedures following epidermal separation. Cell suspensions were seeded on the dermal allografts and cell populations were assessed histologically using H&E and Fontana-Masson’s, and via immunohistochemistry for Ki67, ColIV, ColVII, keratin 15, and involucrin. Advanced phenotyping of the cell suspension isolated using ACHD was assessed using flow cytometry. Results Isolation of cells using ACHD required 8-fold less preparation time and resulted in a different ratio of cell constituents. ACHD yielded suspensions comprised predominantly of keratinocytes (60-75%), fibroblasts (25-40%), and melanocytes (1-3%). Advanced phenotyping indicates subpopulations of keratinocytes including epidermal stem cells, activated keratinocytes, and proliferating keratinocytes. The standard laboratory protocol resulted in a keratinocyte suspension (96-99%) with melanocytes (1-3%) and no fibroblasts. Both cell suspensions were capable of epidermal regeneration with greater pigment and slightly higher numbers of proliferative cells and epidermal stem cells with the ACHD. Conclusions The results suggest non-cultured cell sprays have the potential to regenerate bioengineered dermal allografts in the absence of a split-thickness skin graft. Additionally, ACHD offers a significant time advantage to laboratory-based procedures in the preparation of cell-spray.
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Raee, Mohammad Javad, Alireza Ebrahiminezhad, Mohammad Bagher Ghoshoon, Ahmad Gholami e Younes Ghasemi. "Synthesis and Characterization of L-Lysin Coated Iron Oxide Nanoparticles as Appropriate Choices for Cell Immobilization and Magnetic Separation". Nanoscience & Nanotechnology-Asia 9, n. 4 (25 novembre 2019): 462–66. http://dx.doi.org/10.2174/2210681208666180518084730.
Testo completoAbstract (sommario):
Introduction:Cell separation is one of the important steps of purification in downstream processes. Some separation techniques such as centrifugation and filtration are expensive and would affect cell viability. Magnetic separation can be a good alternative for laboratory and industrial cell separation processes.Methods:For this purpose, L-lysine coated Iron Oxide Nanoparticles (IONs) were synthesized and used for magnetic separation of Escherichia coli as the most applied microbial cell in biotechnological processes.Results:IONs have successfully decorated the bacterial cells and cells were completely separated by applying an external magnetic field.Conclusion:This study showed that coating of E. coli cells with IONs could help to isolate cells from culture media without using expensive instruments.
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Rychłowska, Małgorzata, e Krystyna Bieńkowska-Szewczyk. "Hepatitis C--new developments in the studies of the viral life cycle." Acta Biochimica Polonica 54, n. 4 (25 ottobre 2007): 703–15. http://dx.doi.org/10.18388/abp.2007_3138.
Testo completoAbstract (sommario):
Hepatitis C virus (HCV) is a causative agent of chronic liver disease leading to cirrhosis, liver failure and hepatocellular carcinoma. The prevalence of HCV is estimated as 3% of the world population and the virus is a major public health problem all over the world. For over 16 years, since HCV had been discovered, studies of the mechanisms of the viral life cycle and virus-host interactions have been hampered by the lack of a cell culture system allowing the virus to be grown in laboratory conditions. However, in recent years some new model systems to study HCV have been developed. The major breakthrough of the last two years was the cell culture system for maintaining the virus in an adapted hepatocyte-derived cell line. This review describes the techniques and applications of most of the in vitro systems and animal models currently used for working with hepatitis C virus.
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Rosenthal, Jane K., Dianne L. Atkins, William J. Marvin e Penny A. Krumm. "Application of stereological analysis of cell volume to isolated myocytes in culture with and without adrenergic innervation". Proceedings, annual meeting, Electron Microscopy Society of America 48, n. 3 (12 agosto 1990): 416–17. http://dx.doi.org/10.1017/s042482010015962x.
Testo completoAbstract (sommario):
To comprehend structural changes in cardiac myocytes accompanying adrenergic innervation, it is essential that a three dimensional analysis be performed. To date, biological studies which utilize stereological methods have been limited to cells in tissue and in organs. Our laboratory has utilized current stereological techniques for measuring absolute volumes of individual myocytes in primary culture. Cell volumes are calculated for two distinct groups of cells at 96 hours in culture: isolated myocytes and myocytes innervated with adrenergic neurons (Figure 1).Cardiac myocytes are cultured from the ventricular apices of newborn rats. Cells are plated directly onto tissue culture dishes with or without preplated explants from the paravertebral thoracolumbar sympathetic chain. On day four cultures are photographed and marked for one-to-one cell location. Following conventional fixation and embeddment in eponate-12, the cells are relocated and mounted for microtomy. The cells are completely sectioned at 120nm in their parallel orientation to the surface of the dish (Figure 2). Serial sections are collected on formvar coated slotted grids and are recorded in sequence.
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Rahoma, Mabrouka, Sara A Hwisa, Mabrouka Alfazzani Jira, Mofeda M. Faraj, Enas Abdulsalm Ramih, Sokina Abobaker Almesawey e Fathia Ali Sadik Godid. "Evaluation of medical equipment of the infertility treatment centers in North western of Libya". Libyan Journal of Medical Research 17, n. 2 (31 dicembre 2023): 154–67. http://dx.doi.org/10.54361/ljm17-2.15.
Testo completoAbstract (sommario):
Background Cell culture, particularly in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are both of which assisted reproductive technology (ART) approaches that are most frequently utilized to treat infertility around the world. Objective Highlight the differences and similarities in instruments and equipment in ART laboratories that govern their success, limitations, and potential differences between laboratories by identifying the facilities of laboratories to improve outcomes of ICSI and IVF techniques in clinical centers on the western coast of Libya. Method: descriptive study, comparison of five (5) assisted reproduction laboratories instrument and equipment parameters using the same quality-control application in clinical centers on the western coast of Libya.Result: Among the seven clinical centers specializing in the diagnosis and treatment of infertility that were contacted, four infertility treatment centers and the Medical Research Center (MRC) provided a response. The MRC and four clinical centres had good laboratory facilities for ICSI and IVF techniques compared to Jordan ART laboratory facilities.Conclusion: This study highlights the imperative of enhancing laboratory infrastructure to support optimal implementation of ICSI and IVF procedures.
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Jones, John K., e Mark E. Lyles. "The Viability of Human Adipocytes after Closed-Syringe Liposuction Harvest". American Journal of Cosmetic Surgery 14, n. 3 (settembre 1997): 275–80. http://dx.doi.org/10.1177/074880689701400308.
Testo completoAbstract (sommario):
The notion of free-tissue transplantation of autologous adipose is not new, but has experienced a resurgence in interest due to the popularity of liposuction surgery. Literature review indicates a lack of predictability with previously described techniques, and various theories have been proposed to explain clinical findings. A requisite premise of autologous soft-tissue transplantation is that the tissue must survive the harvest. Recent advances in cell culture technique have allowed us to prove that adipocytes can survive harvesting by aspiration, at least by the method used in this investigation. A surprising finding was that the adipocytes maintained a mature phenotype in culture. This may provide a laboratory model for further investigation.
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Surratt, Christopher K., Paula A. Witt-Enderby, David A. Johnson, Carl A. Anderson, J. Douglas Bricker, Vicki L. Davis, Steven M. Firestine e Wilson S. Meng. "Development of a Neuroscience-oriented “Methods” Course for Graduate Students of Pharmacology and Toxicology". CBE—Life Sciences Education 5, n. 2 (giugno 2006): 188–96. http://dx.doi.org/10.1187/cbe.05-08-0102.
Testo completoAbstract (sommario):
To provide graduate students in pharmacology/toxicology exposure to, and cross-training in, a variety of relevant laboratory skills, the Duquesne University School of Pharmacy developed a “methods” course as part of the core curriculum. Because some of the participating departmental faculty are neuroscientists, this course often applied cutting-edge techniques to neuroscience-based systems, including experiments with brain G protein–coupled receptors. Techniques covered by the course include animal handling and behavioral testing, bacterial and mammalian cell culture, enzyme-linked immunosorbent assay, western blotting, receptor binding of radioligands, plasmid DNA amplification and purification, reverse transcriptase-polymerase chain reaction, gel electrophoresis, and UV-visible and fluorescence spectroscopy. The course also encompasses research aspects such as experimental design and record keeping, statistical analysis, and scientific writing. Students were evaluated via laboratory reports and examinations, and students in turn evaluated the course using a detailed exit survey. This course introduces the graduate student to many more techniques and approaches than can be provided by the traditional graduate “rotation” format alone and should serve as a template for graduate programs in many basic research disciplines.
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Whigham, Amy, Brown Brandee, Avtandyl Kochiashvili, James L. Netterville, Brian B. Burkey, Robert J. Sinard e Wendell G. Yarbrough. "Short-Term Culture and In-Vivo Modeling of Primary HNSCC". Otolaryngology–Head and Neck Surgery 139, n. 2_suppl (agosto 2008): P93—P94. http://dx.doi.org/10.1016/j.otohns.2008.05.502.
Testo completoAbstract (sommario):
Problem Head and neck squamous cell carcinoma (HNSCC) accounts for 4% of annual U.S. cancer deaths. In-vivo models exist using established HNSCC lines, but currently there is no such model that allows consistent growth of HNSCC from primary tumors. Methods Primary HNSCC tissue was obtained from 103 patients at biopsy/resection, disaggregated and seeded onto collagen-coated plates in keratinocyte growth media with 10% FBS, additives and antibiotics. After short-term growth in culture, cells were transferred to denuded rat tracheas and implanted subcutaneously in nude mice. Indirect immunofluorescent staining using antibodies specific to cytokeratin, vimentin and nuclear Ku was performed to determine cell lineage and origin. Results Cultured cells exhibited morphology consistent with epithelial or stromal derivation. 80% of cultures had viable cells present at 10 days and 24% were maintained 30 days or longer. 5 cultures (5%) proliferated after multiple passages and thrived on uncoated plates in the absence of mesenchymal cells. The xenograft model was able to successfully establish tumors in vivo from 59% of primary tumors. Immunostaining for nuclear Ku and cytokeratin confirmed human origin and epithelial cell lineage, respectively. Conclusion The high success rate indicates that selective growth and survival pressures for short-term culture of primary HNSCC may be considerably less than for establishment of cell lines. Additionally, the techniques permit tumor-derived epithelial and mesenchymal cells to be cultured simultaneously. Preliminary data for the in-vivo trachea xenograft model is promising. A luciferase lentiviral system has been created to allow monitoring of tumor growth in vivo with serial live animal imaging. Significance These short-term culture techniques may more accurately characterize both the biological diversity of HNSCC and tumor-stromal cell interactions. Once optimized, the trachea xenograft model can be used to determine the in-vivo response of a heterogeneous group of HNSCC to standard and novel therapies. Support Funds provided by an endowment for the Barry Baker Laboratory for Head and Neck Oncology, the Vanderbilt Ingram Cancer Center Endowed Professorship Fund, and the Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation.
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Kumar, Saraswathisreeram Pranush, Deeki Doma Sherpa, Amit Kumar Sahu, Tarang Jadav, Rakesh Kumar Tekade e Pinaki Sengupta. "Innovation in bioanalytical strategies and in vitro drug–drug interaction study approaches in drug discovery". Bioanalysis 13, n. 6 (marzo 2021): 513–32. http://dx.doi.org/10.4155/bio-2021-0001.
Testo completoAbstract (sommario):
Failure to evaluate actual toxicities of investigational molecules in drug discovery is majorly due to inadequate evaluation of their pharmacokinetics. Limitation of conventional drug metabolism profiling procedure demands advancement of existing approaches. Various techniques such as 3D cell culture system, bio microfluidic OoC model, sandwich culture model is in pipeline to be employed at their full potential in drug discovery phase. Although they outweigh the conventional techniques in various aspects, a more detailed exploration of applicability in terms of automation and high throughput analysis is required. This review extensively discusses various ongoing innovations in bioanalytical techniques. The review also proposed various scientific strategies to be adopted for prior assessment of interaction possibilities in translational drug discovery research.
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Coecke, Sandra, Chantra Eskes, Joanne Gartion, Erwin van Vliet, Agnieszka Kinsner, Alessia Bogni, Laura Raimondo, Nicholaos Parissis e Ingrid Langezaal. "Metabolism and Neurotoxicity: The Significance of Genetically Engineered Cell Lines and New Three-Dimensional Cell Cultures". Alternatives to Laboratory Animals 30, n. 2_suppl (dicembre 2002): 115–18. http://dx.doi.org/10.1177/026119290203002s18.
Testo completoAbstract (sommario):
Until now, no methods have been validated for the determination of neurotoxic effects or for the evaluation of metabolism-mediated hazards of chemical substances. The current test guidelines are based on studies in vivo, involving animals exposed to the test substance. In the EU White Paper on a Strategy for a Future Chemicals Policy, which may result in up to 30,000 chemicals being screened for toxicity, the use of non-animal test methods is seen as essential and is encouraged. The aim of the present work was to demonstrate the significance of novel technologies, including the use of genetically engineered cell lines and three-dimensional cell culture techniques for direct application in the regulatory hazard-assessment process, with an emphasis on metabolism-mediated toxicity and neurotoxicity.
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Jain, Bhawana, Ajay Kr Singh, Tanushree Dangi, Anil Kr Verma, Mukesh Dwivedi, Madan Mohan, K. P. Singh e Amita Jain. "Feasibility of real time PCR over cell culture in diagnosis of influenza virus infection: an experience of rade I viral diagnostic laboratory of developing country". International Journal of Applied Sciences and Biotechnology 2, n. 1 (25 marzo 2014): 97–102. http://dx.doi.org/10.3126/ijasbt.v2i1.9860.
Testo completoAbstract (sommario):
Introduction: In spite of the discovery of viral culture technology about a century ago, its application in diagnostic labs is being used since 1970s. It served as the "gold standard" for virus detection for long. In recent years, rapid, technically less challenging, sensitive and highly specific viral identification is possible by molecular tools. Hence, the purpose of this study was to analyze the importance of real time PCR over virus culture in diagnosis of Influenza virus infections, the biggest viral challenge of present India, a developing country, so that prompt and correct diagnosis can help physicians as well as the policy makers to control the virus spread. Objective: To study the feasibility of real time PCR vis a vis viral culture technique and evaluate the utility of these methods for laboratory diagnosis of Influenza virus infections. Methodology: The study was conducted in Grade I Virology Diagnostic laboratory, Dept of Microbiology, KGMU, Lucknow. We used both real time RT-PCR and viral culture methods (on MDCK cell lines) for detection of Influenza virus infection and compared the effect of transport time, cost per sample and turnaround time on both the techniques. Results & Conclusion: Real time PCR is more practical, more sensitive, quicker and cost effective. It needs less expertise and availability of reagents is better. Though viral culture proved to be highly specific and useful for wide application but the use should currently be limited to mostly research facilities. Therefore for epidemiological diagnosis purposes real time PCR detection of Influenza virus is advised.DOI: http://dx.doi.org/10.3126/ijasbt.v2i1.9860Int J Appl Sci Biotechnol, Vol 2(1): 97-102
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Hammamieh, Rasha, Margery Anderson, Katharine Carr, Christine N. Tran, Debra L. Yourick e Marti Jett. "Students Investigating the Antiproliferative Effects of Synthesized Drugs on Mouse Mammary Tumor Cells". Cell Biology Education 4, n. 3 (settembre 2005): 221–34. http://dx.doi.org/10.1187/cbe.04-10-0053.
Testo completoAbstract (sommario):
The potential for personalized cancer management has long intrigued experienced researchers as well as the naïve student intern. Personalized cancer treatments based on a tumor's genetic profile are now feasible and can reveal both the cells' susceptibility and resistance to chemotherapeutic agents. In a weeklong laboratory investigation that mirrors current cancer research, undergraduate and advanced high school students determine the efficacy of common pharmacological agents through in vitro testing. Using mouse mammary tumor cell cultures treated with “unknown” drugs historically recommended for breast cancer treatment, students are introduced to common molecular biology techniques from in vitro cell culture to fluorescence microscopy. Student understanding is assessed through laboratory reports and the successful identification of the unknown drug. The sequence of doing the experiment, applying logic, and constructing a hypothesis gives the students time to discover the rationale behind the cellular drug resistance assay. The breast cancer experiment has been field tested during the past 5 yr with more than 200 precollege/undergraduate interns through the Gains in the Education of Mathematics and Science program hosted by the Walter Reed Army Institute of Research.
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Chauhan, Brijesh M., Keval M. Kunjadiya e Sanjay N. Parekh. "Camparison of Extraction Techniques for Isolation Fungal DNA". International Journal for Research in Applied Science and Engineering Technology 10, n. 4 (30 aprile 2022): 1413–19. http://dx.doi.org/10.22214/ijraset.2022.41542.
Testo completoAbstract (sommario):
Abstract: For effective molecular screening of fungi using polymerase chain reaction, a simple, quick, reliable, and inexpensive DNA extraction technique is always obliged. Because of the low sensitivity of culture-based detection methods, PCRbased techniques have been developed to amplify DNA from fungal infections. In PCR-based assay, pure DNA must be required, as well as an easy-to-follow DNA extraction approach. Due to amount of fungus in a tissue biopsy or clinical sample may be relatively small, extraction efficiency is extremely crucial in PCR-based medical diagnostic applications. In this study, we are comparing four different methods of DNA extraction and compared their efficacy in the extraction of DNA from filamentous fungi commonly isolated in our laboratory. It was found that the effectiveness of cell wall disruption decreasing in the following order: GeNei™ Fungal Genomic DNA Extraction Teaching Kit > SDS containing extraction buffer > CTAB containing extraction buffer and vortex with glass beads > CTAB and SDS containing extraction buffer. Keywords: DNA isolation, DNA extraction methods, Filamentous fungi, Polymerase chain reaction
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Kiechle, Frederick L. "DNA Technology, the Clinical Laboratory, and the Future". Archives of Pathology & Laboratory Medicine 125, n. 1 (1 gennaio 2001): 72–76. http://dx.doi.org/10.5858/2001-125-0072-dttcla.
Testo completoAbstract (sommario):
AbstractObjective.—To review the advances in clinically useful molecular biological techniques and their applications in clinical practice as presented at the Ninth Annual William Beaumont Hospital DNA Symposium.Data Sources.—The 10 manuscripts submitted were reviewed and their major findings were compared with literature on the same topic.Study Selection.—One manuscript reviewed the development of pharmacogenetics, 3 described analytic approaches to detect aneuploidy or cancer, 1 described transcription factor E2F-1 increase during apoptosis, 2 reported on genetic and pharmacologic factors that influence platelet aggregation, 2 described molecular methods for detecting long QT syndrome or mycobacteria, and 1 reported a modification in collection of buccal DNA.Data Synthesis.—Genomic and proteomic approaches to develop clinically useful assays have been successful. Aneuploidy can be easily detected by comparative genomic hybridization, which does not require cell culture like cytogenetics. Mutations have been characterized for a variety of hereditary cancer syndromes, 2 inherited long QT syndromes, and thromboembolism. PlA1 and PlA2 polymorphisms in platelets are associated with a difference in aggregation inhibition by estrogen, another example of genotypic pharmacogenetics. Protein expression differences may define colorectal cancer stage and explain apoptotic signal transduction. Mycobacterial detection by nucleic acid amplification and simplified buccal DNA collection demonstrate cost-effective strategies.Conclusion.—The working draft of the Human Genome Project is completed and the number of clinically useful molecular pathologic techniques and assays will expand as additional disease-associated mutations are defined. Expanded use of database software for genomic and proteomic screening should increase the efficiency of clinical useful assay development.
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Barton, Richard C. "Laboratory Diagnosis of Invasive Aspergillosis: From Diagnosis to Prediction of Outcome". Scientifica 2013 (2013): 1–29. http://dx.doi.org/10.1155/2013/459405.
Testo completoAbstract (sommario):
Invasive aspergillosis (IA), an infection caused by fungi in the genusAspergillus, is seen in patients with immunological deficits, particularly acute leukaemia and stem cell transplantation, and has been associated with high rates of mortality in previous years. Diagnosing IA has long been problematic owing to the inability to culture the main causal agentA. fumigatusfrom blood. Microscopic examination and culture of respiratory tract specimens have lacked sensitivity, and biopsy tissue for histopathological examination is rarely obtainable. Thus, for many years there has been a great interest in nonculture-based techniques such as the detection of galactomannan,β-D-glucan, and DNA by PCR-based methods. Recent meta-analyses suggest that these approaches have broadly similar performance parameters in terms of sensitivity and specificity to diagnose IA. Improvements have been made in our understanding of the limitations of antigen assays and the standardisation of PCR-based DNA detection. Thus, in more recent years, the debate has focussed on how these assays can be incorporated into diagnostic strategies to maximise improvements in outcome whilst limiting unnecessary use of antifungal therapy. Furthermore, there is a current interest in applying these tests to monitor the effectiveness of therapy after diagnosis and predict clinical outcomes. The search for improved markers for the early and sensitive diagnosis of IA continues to be a challenge.
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Patel, Chirag, Stanley Dunn e Paul Takhistov. "Combined Spectrophotometric— Electrochemical Impedance Imaging System for Biofilm Research". JALA: Journal of the Association for Laboratory Automation 10, n. 1 (febbraio 2005): 16–23. http://dx.doi.org/10.1016/j.jala.2004.08.013.
Testo completoAbstract (sommario):
We propose an automatic scanning microscope that is capable of analyzing the properties of the biofilm-associated cells by using optical and impedance spectroscopy. The operating principle of the instrument is based on measuring the electrical impedance of cell culture grown on a conductive substratum that is used as one of the electrodes. At low frequencies, the impedance analysis is capable of characterizing a biofilm at the macroscale, and at high frequencies it is capable of analyzing the peculiarities of a cell layer at the level of single microorganisms. The combination of these two techniques is sufficient to give a quantitative and structural composition of a biofilm at both levels. The developed instrument can be useful in the broad range of biofilmrelated research studies, providing the data for detailed, real-time, computer-controlled, noninvasive analysis of cell-to-cell and cell-to-surface interactions.
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Plant, K. E. "Tricks of the trade: a beginner's guide to practical molecular biology". Journal of Cell Science 113, n. 22 (15 novembre 2000): 3887–88. http://dx.doi.org/10.1242/jcs.113.22.3887a.
Testo completoAbstract (sommario):
Basic Techniques in Molecular Biology by Stefan Surzycki Springer-Verlag (2000) pp. 434. ISBN 3–540-66678-8 pound44.50/$79.95 This laboratory manual differs from many of the numerous others currently on the market in that it explains the ‘Whys’ as well as the ‘Hows’ of the most commonly used molecular techniques. The book describes DNA and RNA isolation, electrophoresis, blotting and hybridisation, cloning, sequencing and of course PCR. Each chapter consists of a description of the principles involved, a schematic outline of the procedure, 3 or 4 detailed protocols and a trouble-shooting guide. The book is principally aimed at students and others who are relatively new to practical molecular biology and the emphasis is very definitely on making techniques accessible to these people. I rather enjoyed reviewing Dr Surzycki's manual. It is absolutely jam packed full of those little titbits of information that friendly Post Docs occasionally feel inclined to share with students. If you love to delve into the details of what you are doing, you want to know why you're using ammonium and not sodium acetate or can't decide between a phenol or a chloroform extraction, then I think you'll enjoy perusing this book too. I defy anybody to read this manual without picking up some little snippet of information they didn't previously know. And even if you did know it, it's nice to have it before you in black and white instead of as a vague memory of something somebody once told you! As the author admits, there is a degree of repetition throughout the book. What this means is that most of the chapters essentially stand alone, so there is no hunting around for recipes, but of course it also pushes up the size (and therefore the price) of the book. Each chapter also has a trouble shooting guide complete with ‘Recovery Protocols’, which could be very handy for the blundering novice. For the less brave there are also lists of suppliers of kits for many of the procedures, complete with the company's website, a brief description of the principles the kit relies on and the odd favourable opinion. The author tries to give users enough background information to allow them to modify and design new protocols, and he certainly succeeds in that respect. Lessons learned in one technique can always be applied to another, and if you can understand exactly what a particular procedure does then trouble shooting those other techniques suddenly becomes a lot easier. So as you'll have gathered by now I liked this book, and really the only criticism I can level at it is that it is rather restricted in the range of techniques it covers. For anyone who is at all serious about molecular biology it is only ever going to serve as a starting place and there is a wealth of other techniques out there which this book doesn't even touch upon. That said there are also plenty of more specialised manuals out there too, and this particular book more than adequately fills the niche it is intended to cover.
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Hong, Yazhen, Ranjith Kumar Kankala, Ruqi Yu, Huaqing Liu e Yuangang Liu. "Enriched Synthesis of Magnetosomes by Expanding the Magnetospirillum magneticum AMB-1 Culture at Optimal Iron Concentration". Magnetochemistry 7, n. 8 (11 agosto 2021): 115. http://dx.doi.org/10.3390/magnetochemistry7080115.
Testo completoAbstract (sommario):
The Magnetospirillum magneticum AMB-1 species is one of the most widely used magnetotactic bacterial strains for producing magnetosomes under laboratory conditions. Nevertheless, there exist several challenges in expanding and purifying the AMB-1 culture due to the restricted culture conditions. In an attempt to enrich the production of magnetosomes, this study reports the utilization of fermenter culture, which substantially promotes the cell densities at different concentrations of iron content. The experimental results confirmed magnetosomes’ high yield (production rate of 21.1 mg L−1) at the iron content of 0.2 μmol L−1. Moreover, different characterization techniques systematically confirmed the coated lipid membrane, particle size, dispersity, stability, and elemental composition of magnetosomes. Notably, the fermenter culture-based process resulted in highly discrete, dispersed, and stable magnetosomes with an average particle diameter of 50 nm and presented the integrated lipid membrane around the surface. The chemical composition by EDS of magnetosomes represented the presence of various elements, i.e., C, O, Na, P, and Fe, at appropriate proportions. In conclusion, the culture method in our study effectively provides a promising approach towards the culture of the magnetotactic bacterium for the enriched production of magnetosomes.
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El-Deiry, Wafik S., Andrew George, Francesca Di Cristofano, Praveen Srinivasan, Lindsey Carlsen, Kelsey E. Huntington, Arielle De La Cruz et al. "Abstract 4185: Inclusive basic and advanced translational laboratory research competencies for research in cancer biology and therapeutics". Cancer Research 83, n. 7_Supplement (4 aprile 2023): 4185. http://dx.doi.org/10.1158/1538-7445.am2023-4185.
Testo completoAbstract (sommario):
Abstract Our Laboratory was established in 1994 at Univ. of Pennsylvania. Lab members demonstrated initial competencies by performing cell culture, western blots, immunofluorescence, and flow cytometry showing induction of p53/p21(WAF1) in cells treated with chemotherapy. Years later, our Laboratory of Translational Oncology & Experimental Cancer Therapeutics moved to Penn State Univ., Fox Chase Cancer Center/Temple Univ. and then Brown Univ. By 2020, with desire for inclusiveness (everyone succeeds), scientific rigor/reproducibility mandated by NIH, and as a training and mentoring activity (lab scientists/trainees/students mentoring others at High School level and beyond), we established a process for onboarding and training new cancer researchers. By Fall of 2022, there were 17 current Brown University undergraduate students (10 receiving research credit and 7 not receiving credit), HS students, 7 graduate students (PhD, masters, MD/PhD), and 6 medical students working with collaborating faculty at our laboratory at Brown’s Legorreta Cancer Center. After completion of biosafety training, and required trainings such as by IACUC, new lab members complete basic competencies in cell culture, cell viability, and western blot analysis that include technical, presentation quality output, and quantitative/statistical rigor to satisfy current standards for journal publication. For cell culture this includes pathogen free conditions, authentication, attention to details of routine procedures, documentation of morphology, freezing, thawing, passaging, seeding density, and managing cell populations to not run out of cells. Cell viability assessment includes attention to culture conditions, synergy analysis, data robustness, and presentation, and for western blots attention to quality of blots, protein quantification, loading, labeling, antibody specificity and sensitivity controls, presentation at 2022 standards, conventions for splicing, and issues with reproducibility including biological replicates, and generalizability. Additional and advanced competencies include RT-PCR, long-term colony assays, 3-D cultures (spheroids, organoids), transfection (overexpression, knockdown, CRISPR), co-culture and triculture with immune cells and fibroblasts, cytokine profiling, in vivo studies, in vivo imaging, immunohistochemistry, flow cytometric analysis, single cell techniques, viral infection, circulating tumor cell isolation, blood immune and cytokine analysis, and work with transgenic organoids and inducible cancer predisposing alleles. Modeling the tumor microenvironment, relevance to human cancer and translational directions are emphasized. Shared online lab resources, protocols, practices, videos, and manuscripts are available for lab members. The framework herein may be of interest to others involved in similar training programs. Citation Format: Wafik S. El-Deiry, Andrew George, Francesca Di Cristofano, Praveen Srinivasan, Lindsey Carlsen, Kelsey E. Huntington, Arielle De La Cruz, Leiqing Zhang, Marina Hahn, Shuai Zhao, Attila Seyhan, Bradley D. DeNardo, Aaron W. Maxwell, Dae Hee Kim, Alex Raufi, Hina Khan, Stephanie L. Graff, Don S. Dizon, Christopher Azzoli, Abbas E. Abbas, Roxanne Wood, Rishi R. Lulla, Howard P. Safran, Benedito A. Carneiro, Arunasalam Navaraj, Xiaobing Tian, Shengliang Zhang, Lanlan Zhou. Inclusive basic and advanced translational laboratory research competencies for research in cancer biology and therapeutics. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4185.
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LeBar, W. D. "Keeping up with new technology: new approaches to diagnosis of Chlamydia infection". Clinical Chemistry 42, n. 5 (1 maggio 1996): 809–12. http://dx.doi.org/10.1093/clinchem/42.5.809.
Testo completoAbstract (sommario):
Abstract Chlamydia trachomatis infections are among the most common sexually transmitted infections in the US today. One of the keys to the prevention of C. trachomatis infection rests on the ability to make this diagnosis on the basis of accurate laboratory testing. For many years the standard for diagnosis of C. trachomatis infections has been isolation in tissue culture. Numerous nonculture methods, including enzyme immunoassay, have been used as an alternative to cell culture. The performance characteristics of these tests have all been compared with a standard, cell culture, which at best will detect 90% of positive specimens. Nucleic acid amplification techniques, including PCR and ligase chain reaction, have been recently introduced. The advantage of these tests is their ability to detect 10-20% more positive specimens when compared with culture or confirmed nonculture methods performed with a single specimen. The sensitivity of amplified tests also allows us to test specimens from multiple sites (endocervix, urethra, urine), which expands our standard from an infected sample to detection of an infected patient. Tests based on amplified nucleic acid technology have greatly improved our ability to diagnose urogenital C. trachomatis infection. The use of an expanded standard will help us accurately define the true performance and clinical utility of nonculture Chlamydia diagnostic tests.
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Koenig, Gerard J., Glen F. Hoffsis, William P. Shulaw, Steen Bech-Nielsen, D. Michael Rings e Guy St-Jean. "Isolation of Mycobacterium paratuberculosis from mononuclear cells in tissues, blood, and mammary glands of cows with advanced paratuberculosis". American Journal of Veterinary Research 54, n. 9 (1 settembre 1993): 1441–45. http://dx.doi.org/10.2460/ajvr.1993.54.09.1441.
Testo completoAbstract (sommario):
Summary Seven mature dairy cows from 6 herds were obtained with history, clinical signs of disease, and laboratory findings suggestive of advanced paratuberculosis. A surgically implanted collection chamber was used to obtain peripheral tissue fluid. Blood, mammary gland flush fluid, and collection chamber flush fluid (ccff) samples were obtained 6 times over a 2-week period from each cow. Mononuclear cell-rich portions of these fluids obtained by gradient centrifugation were submitted for bacteriologic culture of Mycobacterium paratuberculosis and for total and differential cell counts. Bacteriologic culture of feces for M paratuberculosis and complete necropsy performed on each cow at the conclusion of the study confirmed the diagnosis of paratuberculosis. Numbers of tissue macrophages obtained from ccff samples were lower than expected. Mean (± SD) differential count of tissue macrophages collected from ccff was 65.57 (± 23.39). Mean calculated tissue macrophages (total cell count × differential count) collected from ccff samples was 623.1 (±784.55) cells/μl. Mycobacterium paratuberculosis was isolated from 1 of 42 (2.4%) collections of mononuclear cell-rich portions of plasma and from 2 of 42 (4.8%) ccff samples. Mycobacterium paratuberculosis was not isolated from any collections of mammary gland flush fluid. The collection and processing techniques used in this study did not enhance detection of M paratuberculosis infection in cows with advanced paratuberculosis, beyond that of ileocecal lymph node biopsy or fecal culture.
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Kirpichenko, V. V., S. V. Kononova, A. V. Kononov, O. P. Byadovskaya, B. L. Manin e A. V. Sprygin. "CULTURAL PROPERTIES OF BOVINE RESPIRATORY SYNCYTIAL VIRUS STRAIN AB1908". Veterinary Science Today, n. 4 (26 dicembre 2019): 31–36. http://dx.doi.org/10.29326/2304-196x-2019-4-31-31-36.
Testo completoAbstract (sommario):
Cattle respiratory diseases are some of the most spread pathologies that can cause economic damage, resulting from fi nancial losses and costs of treatment and diagnostics. One of the major factors contributing to respiratory pathology development is bovine respiratory syncytial infection. The analysis of serological testing, performed by the FGBI “ARRIAH” Reference Laboratory for Cattle Diseases in 2017–2018, showed that respiratory syncytial virus seroprevalence in animals of dairy farms is 60%. Herewith, it was noted that the most susceptible animals to this infection are calves under one year of age. The eff ectiveness of bovine respiratory syncytial infection control measures depends on timely diagnosis; that is why reliable and accurate diagnostic tools are needed, including optimal techniques of virus isolation from pathological material. For successful virus isolation from clinical samples, it is necessary to adhere strictly to optimal parameters of this agent cultivation. This paper presents data on study of bovine respiratory syncytial virus strain AB 1908 cultural properties. The tests performed showed that a continuous bovine turbinate (BT) cell line, continuous bovine fetal trachea (FBT) cell line and continuous bovine calf kidney (RBT) cell line are sensitive for cultivation of this agent and can be used to prepare viral suspension, needed for further research. Virus titre in BT cell culture was 4.33 ± 0.16 – 4.66 ± 0.12 lg TCID50/ cm3, in RBT cell culture – 4.33 ± 0.33 – 4.7 ± 0.36 lg TCID50/cm3 and in FBT cell culture – 4.13 ± 0.20 – 4.78 ± 0.17 lg TCID50/cm3. The following virus cultivation optimal parameters were also determined during this study: the age of the culture for virus inoculation should be 1–2 days and multiplicity of inoculation should be 0.1 TCID50/cell.
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Vunjak-Novakovic, Gordana. "Engineered tissue grafts: A new class of biomaterials for medical use". Chemical Industry and Chemical Engineering Quarterly 14, n. 4 (2008): 211–14. http://dx.doi.org/10.2298/ciceq0804211v.
Testo completoAbstract (sommario):
Recent advances in the stem cell biology, the biomaterials science, and the design of the tissue culture bioreactors, help us address the growing need to find replacements for lost and worn-out human tissues and organs in an entirely new way. Biological equivalents of native tissues are grown in a laboratory using tissue engineering techniques and investigated for their functionality, both in vitro and in animal models. We briefly review the key principles for engineering these advanced, native-like biomaterials capable to take over the lost function of our tissues. We also provide an example of the state of the art approach to the tissue engineering.
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Brennan, Catherine A., e Mobina Roshandell. "Open Discovery in an Undergraduate Immunology Course Lab: Testing Anti-Inflammatory Drugs". Journal of Immunology 208, n. 1_Supplement (1 maggio 2022): 106.14. http://dx.doi.org/10.4049/jimmunol.208.supp.106.14.
Testo completoAbstract (sommario):
Abstract I will present the design and outcomes from a course laboratory module in which undergraduates apply techniques learned earlier in the semester (cell culture, spectrophotometry, standard curves, ELISA) towards the testing of an anti-inflammatory drug of their choice. Students rationalize their dose and assay selections, calculate all dilutions, perform the assays, and analyse and interpret all results. Student-directed course research experiences have been shown to solidify student understanding of advanced scientific concepts. Additionally, I have observed that this exercise, in which students analyse the function of medications used by themselves or loved ones, leads to enthusiastic engagement with and mastery of complex concepts.
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Brennan, Catherine, e Mobina Roshandell. "Open Discovery in an Undergraduate Immunology Course Lab: Testing Anti-Inflammatory Drugs". Journal of Immunology 204, n. 1_Supplement (1 maggio 2020): 222.27. http://dx.doi.org/10.4049/jimmunol.204.supp.222.27.
Testo completoAbstract (sommario):
Abstract I will present the design and outcomes from a course laboratory module in which undergraduates apply techniques learned earlier in the semester (cell culture, spectrophotometry, standard curves, ELISA) towards the testing of an anti-inflammatory drug of their choice. Students rationalize their dose and assay selections, calculate all dilutions, perform the assays, and analyse and interpret all results. Student-directed course research experiences have been shown to solidify student understanding of advanced scientific concepts. Additionally, we observed that this exercise, in which students analyse the function of medications used by themselves or loved ones, leads to enthusiastic engagement with and mastery of complex concepts.
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Michael, Angelina, e Yussuf Salum Yussuf. "Isolation, culture trials, and biochemical composition of microalga Tetraselmis from coastal waters of Tanzania". Western Indian Ocean Journal of Marine Science 23, n. 1 (17 luglio 2024): 81–90. http://dx.doi.org/10.4314/wiojms.v23i1.8.
Testo completoAbstract (sommario):
Microalgae are primary producers in aquatic ecosystems. Their high nutritional value make them suitable for applications in aquaculture and biotechnology. Serial dilution techniques were used to isolate the green microalga Tetraselmis sp. from water samples collected from the Ruvu Estuary in Tanzania. Laboratory culture trials were undertaken at varying salinity and light intensity levels, followed by biochemical analysis. Intermediate salinities (15 and 35) favoured cell accumulation, and light intensity significantly influenced Tetraselmis biochemical composition. Low light intensity (2.9 ± 1.6 Klux) and early harvests (day 7) increased the protein, lipid, carbohydrate and fibre content, whereas high light intensity (5.5 ± 3.3 Klux) led to greater ash accumulation. The day 16 harvest contained higher levels of minerals, with calcium, potassium, and magnesium being prominent. Trace minerals, including selenium, were present in safe quantities. The potential of Tetraselmis sp. from coastal Tanzania for aquaculture and biotechnological applications is highlighted.
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Garrison, Keith, Sean Purtell e Brian Shaw. "Incorporation of a sequence-based HLA typing method into an immunology undergraduate laboratory course. (P4527)". Journal of Immunology 190, n. 1_Supplement (1 maggio 2013): 176.2. http://dx.doi.org/10.4049/jimmunol.190.supp.176.2.
Testo completoAbstract (sommario):
Abstract Antibody-based laboratory techniques (e.g. Western blots and ELISA) are relatively easy to implement in an immunology course and widely applicable throughout the subfields of molecular biology. Incorporating lab activities with relevance to T cell immunology is more challenging because they often require proficiency in cell culture and sterile technique. HLA typing facilitates exploration of T cell immunology, including HLA presentation and the development of a T cell response. However, clinical HLA typing kits are costly. Numerous PCR amplifications require high yields of genomic DNA, entailing the challenges of working with blood as a source for DNA in the classroom. Also, typing requires precise gel loading of many samples, which can be challenging. We transformed a sequence-based HLA typing methodology recently developed for research use with plasma samples into a protocol for an immunology course lab. Since the methodology works with the low levels of DNA recoverable from plasma, the technique is well suited for DNA extraction from buccal swabs. The HLA typing process required the following labs to complete: (1) DNA extraction and quantitation (2) primary PCR set-up (3) optional verification of amplification success and secondary PCR set-up (4) verification of nested PCR amplification and sample preparation for sequencing. Additional time was required for editing sequence data and interpreting HLA types using dbMHC.
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Zare, Sona, Rahim Ahmadi, Abdolreza Mohammadnia, Mohammad Ali Nilforoushzadeh e Minoo Mahmoodi. "Biological Characteristics and Optical Reflectance Spectroscopy of Human Placenta Derived Mesenchymal Stem Cells for Application in Regenerative Medicine". Journal of Lasers in Medical Sciences 12, n. 1 (1 maggio 2021): e18-e18. http://dx.doi.org/10.34172/jlms.2021.18.
Testo completoAbstract (sommario):
Introduction: The efficiency of stem cell isolation, culture, and biological characterization techniques for treatment is facing serious challenges. The purpose of this study was to provide a protocol for isolation and culture of three types of mesenchymal stem cells (MSCs) derived from the human placenta, amniotic membrane, and umbilical cord with high efficiency used for cell therapy. Methods: During this experimental laboratory study, 10 complete placenta samples were prepared from cesarean section mothers. The protocol for isolation and culture of mesenchymal cells from the placenta tissue, umbilical cord, and amniotic membrane was enzymatically optimized. The morphological features of mesenchymal cells were investigated using an inverted microscope and their biological features were measured using flow cytometry. The differentiation potential of the cells was evaluated by measuring their differentiation capacity into osteocytes and adipocytes. The absorption and reflectance features of the cells were recorded by optical spectroscopy. Finally, the data were statistically analyzed. Results: The expression of CD44, CD73, CD90 and CD29 markers in human placenta tissue-derived cells was significant. CD14, CD34 and CD45 markers were not expressed or were slightly expressed. These cells were highly viable and successfully differentiated into osteocytes and adipocytes. MSCs absorbed more light than visible light by showing light absorption peaks at wavelengths of about 435 and 550 nm. Conclusion: The protocol used in this study for isolation and culture of human placenta tissue-derived MSCs had significant efficiency for the production of MSCs for use in cell therapy and tissue engineering.
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Demyda-Peyrás, S., M. Hidalgo, J. Dorado e M. Moreno-Millan. "87 EVALUATION OF THE NUMERICAL CHROMOSOMAL ABNORMALITIES ON IN VITRO EARLY BOVINE EMBRYOS: EFFECT OF THE CELL CO-CULTURE WITH GRANULOSA CELLS". Reproduction, Fertility and Development 26, n. 1 (2014): 157. http://dx.doi.org/10.1071/rdv26n1ab87.
Testo completoAbstract (sommario):
Chromosomal numerical abnormalities (CNA) were described as a major cause of developmental failures in in vitro-produced (IVP) embryos. It has been described that CNA are influenced by the post-fertilization culture environment of the embryo. Furthermore, it was demonstrated that the use of different culture media affects the CNA rates. The addition of granulosa cells during early embryo development is a well-known procedure to simplify the culture of bovine IVP and cloned embryos. This technique avoids the use of culture environments saturated with N2 (tri-gas chambers). The aim of this study was to determine the effect of the addition of granulosa cells in the chromosomal abnormalities of IVP cattle embryos. Cumulus–oocyte complexes (COC) were matured in TCM-199 medium, supplemented with glutamine, sodium pyruvate, FSH, LH, oestradiol, and gentamicin during 20 h at 38.5°C in a 5% CO2 humid atmosphere. Subsequently, matured oocytes were fertilized in IVF-TALP medium using 1 × 106 spermatozoa mL–1, selected through a Percoll gradient centrifugation. After fertilization, zygotes were divided in 2 groups and cultured in TCM-199 medium for 48 h, with (TCM-GC) or without (TCM) the addition of 1 × 106 granulosa cells. These cells were obtained by centrifuging and washing the follicular fluid remaining from searching dishes and adjusted to the working concentration. After culture, a total of 106 early embryos (72 hpi) were cytogenetically evaluated following our standard laboratory techniques. Embryos showing normal development were individually fixed onto a slide, disaggregated into blastomeres with acetic acid, and stained with Giemsa solution. Chromosomal numerical abnormalities were evaluated by direct observation at 1250× magnification in a brightfield microscope. Percentage of normal diploid embryos (D) and abnormal haploid (H), polyploid (P), or aneuploid (A) embryos were determined. Results were statistically compared between treatments using a Z test for proportions. Results were: D = 81.4%, H = 7.2%, P = 7.2%. and A = 3.6% in TCM and D = 84.3%, H = 3.9%, P = 9.8%, and A = 1.9% in TCM-GC. No significant differences (P > 0.05) were found between culture media in the chromosomal abnormality rates. According to our results, the use of somatic cells in co-culture during embryo development did not influence the appearance of abnormal complements in the produced embryos. This would allow the use of GC as a potential complement to simplify the techniques used in the culture of bovine embryos until Day 3.
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Edward, Mouli, Ferdiansyah Mahyudin e Dionysius Bramta Putra Manyakori. "THE EFFECT OF CULTURE TECHNIQUES OF HYPOXIC STEM CELL SECRETOME ON THE NUMBER OF GROWTH FACTOR TGF-ß, BMP-2, VEGF". (JOINTS) Journal Orthopaedi and Traumatology Surabaya 11, n. 1 (28 aprile 2022): 5–9. http://dx.doi.org/10.20473/joints.v11i1.2022.5-9.
Testo completoAbstract (sommario):
Background: Mesenchymal stem / stromal cell therapy (MSCs) is now an effective therapeutic modality for treating various diseases. In its application, stem cells require signaling molecules which can be growth factors, cytokines, or chemokines. Signal molecules work orderly and are greatly influenced by the physiological environment. Stem cell culture techniques with hypoxic conditions can produce growth factors close to physiological conditions in fractures. This study aims to perceive the different expressions of some growth factors in cultured normoxic and hypoxic BMSC.Methods: This study is an in vitro laboratory experimental study of normoxic Bone Marrow Stem Cells (BMSCs) and Hypoxic Bone Marrow Stem Cells (BMSCs) cultures. The BMSCs experimental unit was taken from rabbits and then propagated in vitro and cultured under two conditions, normoxia and hypoxia. Then the number of VEGF, TGF-β, BMP-2 growth fractures was observed using ELISA.Results: VEGF, TGF-β, and BMP-2 expressions showed significant differences between the normoxia and hypoxia groups. VEGF, TGF-β, and BMP-2 expression were higher in the hypoxia group compared with the normoxia group (p < 0.05).Conclusion: The expression analysis of TGFβ-1, VEGF, and BMP-2 growth factors in cultured BMSC were statistically significant between normoxic and hypoxic conditions. TGFβ-1, VEGF, and BMP-2 expressions increase in hypoxic conditions.