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Not AvailableA 28-day experiment was carried out to evaluate different C/N ratios (10:1, 15:1 and 20:1) on growth performance, water quality, survival rate and gene expression related to metabolic pathways of Penaeus vannamei in a biofloc system. To maintain the C/N ratio of the feed input, different carbon sources (molasses, rice bran and wheat flour) in combination were applied after fermentation for a day with biofloc consortium. Results showed that shrimps reared in C/N 10 (630 mg) and C/N 15 (646 mg) biofloc systems showed significantly (p = .0229 and .0263) higher growth when compared to C/N 20 (528 mg) and control (374 mg). With regard to the production of extracellular enzymes, protease, lipase and xylanase were found predominantly in colonized bacteria isolated from biofloc treatments, whereas amylase was commonly found in all the treatments. The proPO activity was considerably increased in C/N 10 and 15 treatments than C/N 20 and control. The ranges of relative expression levels of potential genes entailed in metabolite pathway like hexokinase (HK- 6.57–8.17), pyruvate kinase (PK-5.79–7.96), crustacean hyperglycaemic hormone (CHH- 6.99–7.66) and fatty acid synthase (FAS- 6.57–8.86), triacylglycerol lipase (TGL-6.99–8.66) and immune gene (Toll receptor- 4.57–4.86) fold up-regulated expression were observed in the biofloc treatments than that of the control. The overall findings indicate that the rearing of P. vannamei shrimp in C/N 10 and 15 biofloc systems could improve the growth performance, water quality and development of immune and metabolic responses.Not Availabl

Colonization of enzymatic bacterial flora in biofloc grown shrimp Penaeus vannamei and evaluation of their beneficial effect

Not AvailableExperiments were conducted to explore the colonization of beneficial bacteria in shrimp Penaeus vannamei grown in different sources of biofloc and clear water. Beneficial effect in terms of extracellular enzyme production and antibiofilm activity of the isolated strains was determined. Heterotrophic bacterial population were isolated by using different agar plates and resulted in isolation of 94 isolates in total. Extracellular enzyme production such as amylase, protease, lipase, cellulase, xylanase, and pectinase were screened. Antibiofilm activity of culture supernatants of enzymatic strains against pathogenic Vibrio was also determined. Out of 94 strains screened, 36 strains were found to produce amylase enzyme, 20 strains protease, 27 strains lipase, 6 strains cellulase, and 8 strains xylanase. Totally, 21 isolates selected for further identification and different species of Cobetia, Exiguobacterium, Bacillus, Marinilactibacillus, Staphyllococcus, and Novosphingobium genera from biofloc treatments were identified. In control group animals, strains of Bacillus and Exiguobacterium were isolated and identified. The genus Exiguobacterium was found common in all the different treatments and control. The result showed that shrimp grown on biofloc system allows colonizing more beneficial bacteria in gut than control. Few promising strains under Bacillus genus were found to produce all the extracellular enzymes along with antibiofilm activity.Not Availabl

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Not AvailableA two-month experiment was conducted to evaluate the effect of complex carbon sources on the biofloc system and its influence on Penaeus vannamei culture. Four sources of carbon viz. Tapioca flour (BFTf), Rice bran (BFRb), Wheat flour (BFWf), Rice Flour (BFRf), and biofloc were generated, the absence of CHO being considered as control (C). The experiment was carried out in 100L FRP tanks in triplicate, and the post-larvae (ABW: 0.11 g) were stocked @ 400 PL/m3 . Results revealed that the addition of complex carbon sources effectively reduces the TAN by 62-67%. The average body weight of shrimp in the rice flour and wheat flour treatments were significantly higher compared to control. Similarly, improved survival was observed in rice bran treatment (89%). Beneficial bacteria were isolated from all the treatments as well as control. Real-time analysis revealed significantly (P<0.05) higher expression of digestive enzyme-related genes compared to control the utilization of carbohydrates, exhibiting an encouraging trend. The complex carbon sources (BFRf) and (BFWf) have been effectively utilized, resulting in improved water quality, microbial diversity, growth performance, and enhanced digestive enzyme activity.Not Availabl

Changes in Human Foetal Osteoblasts Exposed to the Random Positioning Machine and Bone Construct Tissue Engineering

Human cells, when exposed to both real and simulated microgravity (s-&micro;g), form 3D tissue constructs mirroring in vivo architectures (e.g., cartilage, intima constructs, cancer spheroids and others). In this study, we exposed human foetal osteoblast (hFOB 1.19) cells to a Random Positioning Machine (RPM) for 7 days and 14 days, with the purpose of investigating the effects of s-&micro;g on biological processes and to engineer 3D bone constructs. RPM exposure of the hFOB 1.19 cells induces alterations in the cytoskeleton, cell adhesion, extra cellular matrix (ECM) and the 3D multicellular spheroid (MCS) formation. In addition, after 7 days, it influences the morphological appearance of these cells, as it forces adherent cells to detach from the surface and assemble into 3D structures. The RPM-exposed hFOB 1.19 cells exhibited a differential gene expression of the following genes: transforming growth factor beta 1 (TGFB1, bone morphogenic protein 2 (BMP2), SRY-Box 9 (SOX9), actin beta (ACTB), beta tubulin (TUBB), vimentin (VIM), laminin subunit alpha 1 (LAMA1), collagen type 1 alpha 1 (COL1A1), phosphoprotein 1 (SPP1) and fibronectin 1 (FN1). RPM exposure also induced a significantly altered release of the cytokines and bone biomarkers sclerostin (SOST), osteocalcin (OC), osteoprotegerin (OPG), osteopontin (OPN), interleukin 1 beta (IL-1&beta;) and tumour necrosis factor 1 alpha (TNF-1&alpha;). After the two-week RPM exposure, the spheroids presented a bone-specific morphology. In conclusion, culturing cells in s-&micro;g under gravitational unloading represents a novel technology for tissue-engineering of bone constructs and it can be used for investigating the mechanisms behind spaceflight-related bone loss as well as bone diseases such as osteonecrosis or bone injuries

Changes in human foetal osteoblasts exposed to the random positioning machine and bone construct tissue engineering

Human cells, when exposed to both real and simulated microgravity (s-µg), form 3D tissue constructs mirroring in vivo architectures (e.g., cartilage, intima constructs, cancer spheroids and others). In this study, we exposed human foetal osteoblast (hFOB 1.19) cells to a Random Positioning Machine (RPM) for 7 days and 14 days, with the purpose of investigating the effects of s-µg on biological processes and to engineer 3D bone constructs. RPM exposure of the hFOB 1.19 cells induces alterations in the cytoskeleton, cell adhesion, extra cellular matrix (ECM) and the 3D multicellular spheroid (MCS) formation. In addition, after 7 days, it influences the morphological appearance of these cells, as it forces adherent cells to detach from the surface and assemble into 3D structures. The RPM-exposed hFOB 1.19 cells exhibited a differential gene expression of the following genes: transforming growth factor beta 1 (TGFB1, bone morphogenic protein 2 (BMP2), SRY-Box 9 (SOX9), actin beta (ACTB), beta tubulin (TUBB), vimentin (VIM), laminin subunit alpha 1 (LAMA1), collagen type 1 alpha 1 (COL1A1), phosphoprotein 1 (SPP1) and fibronectin 1 (FN1). RPM exposure also induced a significantly altered release of the cytokines and bone biomarkers sclerostin (SOST), osteocalcin (OC), osteoprotegerin (OPG), osteopontin (OPN), interleukin 1 beta (IL-1β) and tumour necrosis factor 1 alpha (TNF-1α). After the two-week RPM exposure, the spheroids presented a bone-specific morphology. In conclusion, culturing cells in s-µg under gravitational unloading represents a novel technology for tissue-engineering of bone constructs and it can be used for investigating the mechanisms behind spaceflight-related bone loss as well as bone diseases such as osteonecrosis or bone injuries

Reduced Expression of Cytoskeletal and Extracellular Matrix Genes in Human Adult Retinal Pigment Epithelium Cells Exposed to Simulated Microgravity

Background/Aims: Microgravity (µg) has adverse effects on the eye of humans in space. The risk of visual impairment is therefore one of the leading health concerns for NASA. The impact of µg on human adult retinal epithelium (ARPE-19) cells is unknown. Methods: In this study we investigated the influence of simulated µg (s-µg; 5 and 10 days (d)), using a Random Positioning Machine (RPM), on ARPE-19 cells. We performed phase-contrast/fluorescent microscopy, qRT-PCR, Western blotting and pathway analysis. Results: Following RPM-exposure a subset of ARPE-19 cells formed multicellular spheroids (MCS), whereas the majority of the cells remained adherent (AD). After 5d, alterations of F-actin and fibronectin were observed which reverted after 10d-exposure, suggesting a time-dependent adaptation to s-µg. Gene expression analysis of 12 genes involved in cell structure, shape, adhesion, migration, and angiogenesis suggested significant changes after a 10d-RPM-exposure. 11 genes were down-regulated in AD and MCS 10d-RPM-samples compared to 1g, whereas FLK1 was up-regulated in 5d- and 10d-RPM-MCS-samples. Similarly, TIMP1 was up-regulated in 5d-RPM-samples, whereas the remaining genes were down-regulated in 5d-RPM-samples. Western blotting revealed similar changes in VEGF, β-actin, laminin and fibronectin of 5d-RPM-samples compared to 10d, whereas different alterations of β-tubulin and vimentin were observed. The pathway analysis showed complementing effects of VEGF and integrin β-1. Conclusions: These findings clearly show that s-µg induces significant alterations in the F-actin-cytoskeleton and cytoskeleton-related proteins of ARPE-19, in addition to changes in cell growth behavior and gene expression patterns involved in cell structure, growth, shape, migration, adhesion and angiogenesis