Search results for "Tissue culture"
showing 10 items of 108 documents
Animal Models of Cardiovascular Disease
2009
The use of animal models to study cardiovascular disease has made a substantial contribution to increasing our understanding of disease pathogenesis, has led to the development of diagnostic techniques, and has made it possible to verify the effectiveness of different preventative and therapeutic approaches, whether pharmacological or interventional. The main limitations stem from differences between human and experimentally induced pathology, in terms of both genetic regulatory mechanisms and factors that influence cardiovascular function. The experimental models and preparations used in cardiovascular research include those based on isolated cells or tissues or structures immersed in orga…
Low level 809-nm diode laser-induced in vitro stimulation of the proliferation of human gingival fibroblasts
2002
Background and Objective The authors investigated the effects of low level laser irradiation on the proliferation rate of human gingival fibroblasts (HGF) in vitro. Study Design/Materials and Methods HGF were obtained from gingival connective tissue explants and cultured under standard conditions. 110 cell cultures in their logarithmic growth phase were spread on 96-well tissue culture plates and were irradiated at energy fluences of 1.96–7.84 J/cm2. Another 110 cultures served as control. An 809-nm semiconductor laser operated at a power output of 10 mW in the cw-mode was used. The time of exposure varied between 75 and 300 seconds. Laser treatment was performed alternatively once, twice, …
Hemmung von DNA-Synthese und Zellvermehrung durch Apurins�ure und Apyrimidins�ure
1968
Apurinic acid (APA) and apyrimidinic acid (APyA) prepared from deoxyribonucleic acid (DNA) by removing either purine or pyrimidine bases have been reported to inhibit enzymatic DNA-synthesis in vitro (Heicke, 1970). The present paper deals with in vivo effects of APA and APyA on mammalian cells in tissue culture.
Morphogenesis and Cardenolide Formation in Digitalis obscura Cultures
1991
Summary Cardenolide formation was investigated in hypocotyl cultures of Digitalis obscura L. established on MS medium with growth regulators selected to promote either callus formation, caulogenesis, embryogenesis or rhizogenesis. Examination of the cardenolide composition of leaves from mature plants was also performed. Several compounds of series A and C were identified by HPLC in in vitro and in vivo grown tissues, no marked differences being found between their cardenolide patterns. RIA determinations showed that shoot- or embryo-forming calli accumulated significantly higher amounts of digoxigenin derivatives than undifferentiated or rhizogenic cultures. In any case, field plants prese…
Improved Mesophyll Protoplast Culture and Plant Regeneration in Arabidopsis thaliana (L.) Heynh., Genotype Landsberg Erecta
1993
Summary The response of in vitro cultured Arabidopsis thaliana mesophyll protoplasts was investigated with the aim of characterising the crucial factors that affect plating efficiencies and plant regeneration. We selected the genotype Landsberg erecta, which is frequently used for genetic studies, but which is known to respond poorly in protoplast culture. Factors permitting vigorous vegetative growth of the donor plants, i.e. short light period and avoidance of high temperature, were found to be advantageous. Selection of competent leaves and fractionation of protoplast populations indicated that predominantly protoplasts derived from still expanding, yet not highly immature mesophyll cell…
Evidence for a negative inotropic effect of obesity in human myocardium?
2009
Objective: The present study was performed as an attempt to analyze the relationship between body weight and human myocardial performance. As overweight is frequently associated with hypertension, stenosis of epimyocardial coronary arteries and other factors that influence myocardial performance, the experimental model of isolated human atrial myocardium was selected. Atrial contractile performance does neither depend on the extent of stenosis of epicardial coronary arteries nor on the degree of hypertension and its secondary pathology. Methods:Rightatrialmusclepreparations(0.5 6 mm)of183patientsundergoingcoronaryarterybypasssurgerywereelectricallystimulatedat optimal length. Active tension…
Foreed flushing of branch segments as a method for obtaining reactive explants of mature Quercus robur trees for micropropagation
1994
The aim of this study was to micropropagate mature Quercus robur L. trees when material retaining physiologically juvenile characteristics (stump sprouts, epicormic shoots) is not available. Branch segments from 70–300 year-old trees were force-flushed and the flushed, partially rejuvenated or reinvigorated shoots were used as a source of explants for establishment of cultures. In vitro establishment and multiplication was achieved with seven of the eight selected trees. The proliferation capacity of cultures of vertically placed explants declined after several subcultures, but efficient shoot multiplication was achieved by culturing decapitated shoots placed horizontally on GD medium suppl…
IFN-gamma-induced protein 10 is a novel biomarker of rhinovirus-induced asthma exacerbations
2007
BACKGROUND: Rhinovirus-induced acute asthma is the most frequent trigger for asthma exacerbations. OBJECTIVE: We assessed which inflammatory mediators were released from bronchial epithelial cells (BECs) after infection with rhinovirus and then determined whether they were also present in subjects with acute virus-induced asthma, with the aim to identify a biomarker or biomarkers for acute virus-induced asthma. METHODS: BECs were obtained from bronchial brushings of steroid-naive asthmatic subjects and healthy nonatopic control subjects. Cells were infected with rhinovirus 16. Inflammatory mediators were measured by means of flow cytometry with a cytometric bead array. Subjects with acute a…
Anthraquinones from Ophiorrhiza pumila tissue and cell cultures
1998
We have succeeded in initiating and establishing systems of tissue and cell cultures of Ophiorrhiza pumila. Examination of the constituents of the methanol extract of the cultured calli revealed the presence of 11 anthraquinones including two new ones whose structures have been rigorously proved using advanced spectroscopic methods. These findings demonstrated a remarkable difference in the constituents between the wild plants and the callus tissue or cultured cells; the former is devoid of anthraquinones and contains a variety of camptothecin-related alkaloids whereas the latter contains a significant amount of anthraquinones and shows no indication of the presence of alkaloids after sever…
Cell culture models of higher complexity in tissue engineering and regenerative medicine.
2007
Cell culture techniques have tended to be used in biomaterial research as a screening method prior to embarking on specific in vivo experimentation. This presentation aims at showing that it is possible to develop more sophisticated in vitro systems using primary human cells in co-culture with other cell types and biomaterials in a three-dimensional setting. While the predictive value of such systems is still not proven these models can be employed to unravel the complexity of biological systems in order to understand molecular mechanisms of cell-cell and cell-material interactions. The brief overview is under the headings of basic principles of relevant culture systems, the study of inflam…