20 research outputs found
Development of an in vitro cell system from zebrafish suitable to study bone cell differentiation and extracellular matrix mineralization
Mechanisms of bone formation and skeletal development have been successfully investigated in zebrafish using a variety of in vivo approaches, but in vitro studies have been hindered due to a lack of homologous cell lines capable of producing an extracellular matrix (ECM) suitable for mineral deposition. Here we describe the development and characterization of a new cell line termed ZFB1, derived from zebrafish calcified tissues. ZFB1 cells have an epithelium-like phenotype, grow at 28 degrees C in a regular L-15 medium supplemented with 15% of fetal bovine serum, and are maintained and manipulated using standard methods (e.g., trypsinization, cryopreservation, and transfection). They can therefore be propagated and maintained easily in most cell culture facilities. ZFB1 cells show aneuploidy with 2n=78 chromosomes, indicative of cell transformation. Furthermore, because DNA can be efficiently delivered into their intracellular space by nucleofection, ZFB1 cells are suitable for gene targeting approaches and for assessing gene promoter activity. ZFB1 cells can also differentiate toward osteoblast or chondroblast lineages, as demonstrated by expression of osteoblast- and chondrocyte-specific markers, they exhibit an alkaline phosphatase activity, a marker of bone formation in vivo, and they can mineralize their ECM. Therefore, they represent a valuable zebrafish-derived in vitro system for investigating bone cell differentiation and extracellular matrix mineralization.FISHCELL project [PTDC/MAR/105313/2008]; Portuguese Science and Technology Foundation (FCT); European Regional Development Fund (ERDF) through the COMPETE Program; National Fund through FCT [PEst-C/MAR/LA0015/2011]; FCT [SFRH/BPD/39189/2007]; Association of European Marine Biological Laboratories through the ASSEMBLE project [FP7/227799]info:eu-repo/semantics/publishedVersio
Nations within a nation: variations in epidemiological transition across the states of India, 1990–2016 in the Global Burden of Disease Study
18% of the world's population lives in India, and many states of India have populations similar to those of large countries. Action to effectively improve population health in India requires availability of reliable and comprehensive state-level estimates of disease burden and risk factors over time. Such comprehensive estimates have not been available so far for all major diseases and risk factors. Thus, we aimed to estimate the disease burden and risk factors in every state of India as part of the Global Burden of Disease (GBD) Study 2016
A comparison of aerosol size distributions obtained from bistatic lidar and low-pressure impactor experiments at a coastal station
42-49Size distribution of aerosols in the atmospheric mixed region is studied using a bistatic CW lidar and a low-pressure impactor. Results obtained from these two experiments are compared. CW lidar observations showed that the size index (assuming the size distribution to follow a power law) generally lies in the range 3.5-5, whereas the size index obtained using the low-pressure impactor generally lies in the range 3.7-4.2
Effect of atmospheric relative humidity on aerosol size distribution
175-188A method of accounting for the effect of variation in relative humidity on aerosol size distribution obtained from a low-pressure impactor (KPI) experiment is proposed. The size distribution of atmospheric aerosols under the prevailing relative humidities estimated by this method is compared with that obtained using a bistatic CW lidar. These results are used to study the effect of relative humidity on aerosol size distributions. At higher altitudes in the mixing region, increase in relative humidity causes a decrease in aerosol size index. The seasonal variation of aerosol number density near the surface is found to agree fairly well with the seasonal variation of the mixing region aerosol optical depth
Lidar observations on aerosol mixing height in a tropical coastal environment
15-21The aerosol mixing height is derived from the altitude distribution of aerosols in the lower atmosphere up to ~1.2 km during the post-sunset period (~2000 hrs IST) using a bi-static CW lidar at a tropical coastal station, Trivandrum. The mixing height shows significant seasonal variation with maxima in the dry months of March and November as well as in the south-west monsoon period. The maxima in March and November are attributed to strong convective mixing, whereas the maximum in the south-west monsoon is attributed to mechanical mixing due to strong wind shears
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Disciplinary, interdisciplinary and transdisciplinary aquaculture researchA new continuous cell line designated as SGA has been developed from the skin tissue of the freshwater mosquitofish Gambusia affinis. The cell line grew well in Leibovitz's L-15 medium supplemented with 15% fetal bovine serum at 28 °C. Immunophenotyping of the cell line showed the epithelial nature of the cells. Chromosome number analysis showed that SGA cells have a modal diploid chromosome number of 48. Replication of the two different strains of betanodavirus (RGNNV and SJNNV) in SGA cell line showed the maximum virus titre of 108.82 TCID50 mL−1 for RGNNV and 107.2 TCID50 mL−1 for SJNNV. The cytopathic effect in the cell line was observed at 3 days post-infection (dpi) and multiple vacuolations were observed at 7 dpi. Further, DsRed2 plasmid was efficiently delivered into SGA cell line and was found that these cells were transfectable and can be used for assessing gene promoter activity. In vivo challenge experiments using the RGNNV infected cell culture supernatant showed signs of the disease in healthy mosquitofish with mortality commencing from 15 dpi. The above results suggest that the cell line is permissive for propagating betanodavirus and also could be an essential tool for studying the molecular pathogenesis of betanodavirus infection.Not Availabl
Cells isolated from regenerating caudal fin of Sparus aurata can differentiate into distinct bone cell lineages
Teleosts have the ability to regenerate their caudal fin upon amputation. A highly proliferative mass of undifferentiated cells called blastema forms beneath wound epidermis and differentiates to regenerate all missing parts of the fin. To date, the origin and fate of the blastema is not completely understood. However, current hypotheses suggest that the blastema is comprised of lineage-restricted dedifferentiated cells. To investigate the differentiation capacity of regenerating fin-derived cells, primary cultures were initiated from the explants of 2-days post-amputation (dpa) regenerates of juvenile gilthead seabream (Sparus aurata). These cells were subcultured for over 30 passages and were named as BSa2. After 10 passages they were characterized for their ability to differentiate towards different bone cell lineages and mineralize their extracellular matrix, through immunocytochemistry, histology, and RT-PCR. Exogenous DNA was efficiently delivered into these cells by nucleofection. Assessment of lineage-specific markers revealed that BSa2 cells were capable of osteo/chondroblastic differentiation. BSa2 cells were also found to be capable of osteoclastic differentiation, as demonstrated through TRAP-specific staining and pit resorption assay. Here, we describe the development of the first successful cell line viz., BSa2, from S. aurata 2-dpa regenerating caudal fins, which has the ability of multilineage differentiation and is capable of in vitro mineralization. The availability of such in vitro cell systems has the potential to stimulate research on the mechanisms of cell differentiation during fin regeneration and provide new insights into the mechanisms of bone formation.Portuguese Science and Technology Foundation (FCT)Portuguese Foundation for Science and Technology [PTDC/MAR/105313/2008, UID/Multi/04326/2019]European Community (EC)European CommissionEuropean Commission Joint Research Centre [FP7/227799]FCTPortuguese Foundation for Science and TechnologyEuropean Commission [SFRH/BPD/39189/2007
Seasonal and long term variations of aerosol content in the atmospheric mixing region at a tropical station on the Arabian sea-coast
Altitude profiles of aerosol number density in the atmospheric mixing region obtained using a bistatic CW lidar at Trivandrum (8.55°N, 77°E), a station situated on the West coast, near the southern tip of the Indian peninsula, during the period 1989 to 1994 showed a systematic seasonal dependence. The number density shows a peak at ~300-400 m which is quite prominent during the local summer period and becomes less discernable during the North-East monsoon period. The mixing region aerosol optical depth estimated using these aerosol number density profiles shows a seasonal variation with two maxima; one during the winter to summer transition period and the other during the South-West monsoon period. A long term increasing trend is also observed in the aerosol optical depth from 1989 to 1994. A comparison of the mixing region aerosol optical depth with the total aerosol optical depth obtained using a solar radiometer has shown that this increasing trend is not confined to the mixing region alone but extends to higher altitudes also. This study also shows that under quiescent conditions, ~30% on average of the total aerosol optical depth, at 0.5 μm wavelength, is contributed by the aerosols in the altitude region below 1 km