An Efficient In Vitro Propagation Protocol of Cocoyam [Xanthosoma sagittifolium (L) Schott]

Sprouted corm sections of “South Dade” white cocoyam were potted and maintained in a greenhouse for 8 weeks. Shoot tips of 3–5 mm comprising the apical meristem with 4–6 leaf primordial, and approximately 0.5 mm of corm tissue at the base. These explants were treated to be used into the culture medium. A modified Gamborg's B5 mineral salts supplemented with 0.05 μM 1-naphthaleneacetic acid (NAA) were used throughout the study. Thidiazuron (TDZ) solution containing 0.01% dimethyl sulfoxide (DMSO) was used. Erlenmeyer flasks and test tubes were used for growing cultures. The effect of different media substrate, thidiazuron, and the interaction between TDZ and Benzylaminopurine (BAP) on cocoyam culture were tested. Results indicated that cocoyam can be successfully micropropagated in vitro through various procedures. All concentrations tested (5–20 μM BAP and 1–4 μM TDZ) produced more axillary shoots per shoot tip than the control without cytokinins. Greater proliferation rates were obtained through the use of 20 μM BAP and 2 μM TDZ, respectively, 12 weeks from initiation. Shoots produced with BAP were larger and more normal in appearance than those produced with TDZ, which were small, compressed, and stunted. The use of stationary liquid media is recommended for economic reasons

Osteogenic Differentiation Potential of Human Bone Marrow and Amniotic Fluid-Derived Mesenchymal Stem Cells in Vitro & in Vivo

BACKGROUND: Cell therapies offer a promising potential in promoting bone regeneration. Stem cell therapy presents attractive care modality in treating degenerative conditions or tissue injuries. The rationale behind this is both the expansion potential of stem cells into a large cell population size and its differentiation abilities into a wide variety of tissue types, when given the proper stimuli. A progenitor stem cell is a promising source of cell therapy in regenerative medicine and bone tissue engineering. AIM: This study aimed to compare the osteogenic differentiation and regenerative potentials of human mesenchymal stem cells derived from human bone marrow (hBM-MSCs) or amniotic fluid (hAF-MSCs), both in vitro and in vivo studies. SUBJECTS AND METHODS: Human MSCs, used in this study, were successfully isolated from two human sources; the bone marrow (BM) and amniotic fluid (AF) collected at the gestational ages of second or third trimesters. RESULTS: The stem cells derived from amniotic fluid seemed to be the most promising type of progenitor cells for clinical applications. In a pre-clinical experiment, attempting to explore the therapeutic application of MSCs in bone regeneration, Rat lumbar spines defects were surgically created and treated with undifferentiated and osteogenically differentiated MSCs, derived from BM and second trimester AF. Cells were loaded on gel-foam scaffolds, inserted and fixed in the area of the surgical defect. X-Ray radiography follows up, and histopathological analysis was done three-four months post- operation. The transplantation of AF-MSCs or BM-MSCs into induced bony defects showed promising results. The AF-MSCs are offering a better healing effect increasing the likelihood of achieving successful spinal fusion. Some bone changes were observed in rats transplanted with osteoblasts differentiated cells but not in rats transplanted with undifferentiated MSCs. Longer observational periods are required to evaluate a true bone formation. The findings of this study suggested that the different sources; hBM-MSCs or hAF-MSCs exhibited remarkably different signature regarding the cell morphology, proliferation capacity and osteogenic differentiation potential CONCLUSIONS: AF-MSCs have a better performance in vivo bone healing than that of BM-MSCs. Hence, AF derived MSCs is highly recommended as an alternative source to BM-MSCs in bone regeneration and spine fusion surgeries. Moreover, the usage of gel-foam as a scaffold proved as an efficient cell carrier that showed bio-compatibility with cells, bio-degradability and osteoinductivity in vivo

Exploring the importance of within-canopy spatial temperature variation on transpiration predictions

Models seldom consider the effect of leaf-level biochemical acclimation to temperature when scaling forest water use. Therefore, the dependence of transpiration on temperature acclimation was investigated at the within-crown scale in climatically contrasting genotypes of Acer rubrum L., cv. October Glory (OG) and Summer Red (SR). The effects of temperature acclimation on intracanopy gradients in transpiration over a range of realistic forest growth temperatures were also assessed by simulation. Physiological parameters were applied, with or without adjustment for temperature acclimation, to account for transpiration responses to growth temperature. Both types of parameterization were scaled up to stand transpiration (expressed per unit leaf area) with an individual tree model (MAESTRA) to assess how transpiration might be affected by spatial and temporal distributions of foliage properties. The MAESTRA model performed well, but its reproducibility was dependent on physiological parameters acclimated to daytime temperature. Concordance correlation coefficients between measured and predicted transpiration were higher (0.95 and 0.98 versus 0.87 and 0.96) when model parameters reflected acclimated growth temperature. In response to temperature increases, the southern genotype (SR) transpiration responded more than the northern (OG). Conditions of elevated long-term temperature acclimation further separate their transpiration differences. Results demonstrate the importance of accounting for leaf-level physiological adjustments that are sensitive to microclimate changes and the use of provenance-, ecotype-, and/or genotype-specific parameter sets, two components likely to improve the accuracy of site-level and ecosystem-level estimates of transpiration flux

Freezability of buffalo semen with TRIS extender enriched with disaccharides (trehalose or sucrose) and different glycerol concentrations

Objective: To display the effect of different concentrations of glycerol, as a cryopreservative, on the quality of the frozen-thawed buffalo semen extended in TRIS extender enriched with disaccharides (trehalose or sucrose). Methods: Semen samples were extended in Tris-Citric acid-Fructose-Egg yolk without addition of trehalose/sucrose and with 6.4% glycerol as a control (TFEG-C) and with the addition of Trehalose/Sucrose and different concentrations of glycerol to ensure 60 million motile spermatozoa mL−1. Semen cooled slowly up to 5 and equilibrated for 4 h. Semen was packed into 0.25 mL polyvinyl French straws. The straws were placed horizontally on a rack and frozen in a vapor 4 cm above liquid nitrogen (LN2) for 10 min then dipped in liquid LN2. Frozen straws were thawed at 37 °C for 1 min. The parameters studied were sperm motility, sperm viability, sperm abnormality, sperm membrane integrity (HOST), percent of normal intact acrosome and DNA fragmentation. Results: The best sperm motility, sperm liveability, sperm abnormality, sperm cell membrane and DNA integrities appeared with TFES-G 5.5% (41.00 ± 2.08%, 70.40 ± 2.27%, 7.80 ± 1.19%, 68.10 ± 1.55%, 98.90 ± 0.50%, respectively) and TFES-G 7.3% (41.50 ± 1.98%, 70.70 ± 2.03%, 10.80 ± 0.88%, 69.30 ± 1.85% and 96.40 ± 0.88%, respectively). Conclusion: From the present study, it can be concluded that addition of glycerol (5.5% or 7.3%) to Tris-Fructose-Egg yolk-Sucrose extender might help in improvement of the post-thawed characteristics of buffalo frozen semen

Effect of butylated hydroxytoluene on quality of pre—frozen and frozen buffalo semen

Objective: To clarify the antioxidant effect of butylated hydroxytoulene (BHT) at different concentrations on cooled and post frozen semen diluted in tris-citrate-fructose egg yolk glycerol and lecithin -based extenders. Methods: Forty ejaculates were harvested from four buffalo bulls by means of the artificial vagina. Ejaculated semen samples were diluted with each of the tris citrate-fructose egg yolk glycerol and lecithin-based extender diluents. The semen samples diluted with each of the two extenders were added to pre-warmed dried test tubes containing BHT (prepared in ethanol) to get concentrations at 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mM/mL BHT. These ingredients were put at 37 °C for 5 min to allow the proper BHT spermatozoal permeation. The diluted semen samples were cooled to 5 °C and then frozen to -196 °C in 0.25 mL ministraws before dipping in liquid nitrogen pending its evaluation. Sperm motility, viability, morphology, intact acrosome and membrane integrity were tested. Visual motility was tested using a high power ordinary microscope (at 400 ×) with closed circuit television, and sperm concentration was tested using Neubauer haemocytometer and abnormality % using eosin-nigrosin stain. Spermatozoal membrane integrity was tested using the hypo-osmotic swelling test. The sperm with swollen twisting tail was normally intact. Sperm acrosomal integrity % was tested as mentioned by Watson. Results: Addition of BHT improved (P<0.01) progressive motility, viability, morphology and acrosome as well as plasma membrane integrities at 0.5-2.0 mM/mL depending upon types of used extenders and stages of pre-and post-freezing process. Higher levels of 2.5 and 3.0 mM/mL BHT had a deteriorating (P<0.01) result if compared to the control and all extenders assayed. Conclusions: BHT addition at lower concentration can improve pre-frozen and post-thawed buffalo sperm quality

Impact of replacing egg yolk with lecithin on quality of pre-freeze and post-thaw buffalo spermatozoa

Objective: To estimate the result of egg yolk replacement with alternative cryopreservatives such as plant-derived lecithin from soybean on sperm quality parameters pre and post freezing in buffalo bulls. Methods: The control cryopreservation extender was tris-citric acid-fructose-egg yolk-glycerol (TCFYG) diluent. Semen samples were extended gradually 1:10 with TCFYG control extender and tris-citric acid-fructose-glycerol (TCFG) extender plus variable concentrations of soybean lecithin (0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0%) to ensure 60 million active spermatozoa/mL of the extended semen. The diluted semen samples were refrigerated slowly (roughly for 2 h) up to 5 °C and equilibrated for 2 h. Semen was filled into 0.25 mL polyvinyl French straws (IMV, France). After equilibration period, the straws were placed horizontally on a rack and frozen in a vapor 4 cm above liquid nitrogen for 10 min and were then dipped stored in liquid nitrogen at -196 °C. Results: The respective overall percentages of forward motile spermatozoa, live spermatozoa, morphologically normal spermatozoa, acrosome integrity and hypo-osmotic swelling reactivity observed primarily in fresh semen, after equilibration (pre-freeze stage) and post freezing (post-thaw stage) in TCFYG (control) extended semen declined progressively and statically (P<0.01) during these periods of study. Pre-freezing stage: replacement of egg yolk into TCFG with soybean lecithin at concentrations of 1.0% and 1.5% significantly (P<0.01) ameliorated the maintenance of (motility, viability, acrosome and membrane integrity %), meanwhile it had significantly (P<0.01) reduced the abnormality % of spermatozoa to the lowest value compared to control TCFYG and to some other concentrations in use. Post-thaw stage: the replacement of egg yolk with 1.0% soybean lecithin (SL) showed significantly (P<0.01) higher percentage of sperm progressive motility compared to 1.5% SL and TCFYG control. These values were significantly (P<0.01) higher than 0.5%, 2.0%, 2.5% and 3.0% SL. The post thawing live sperm percentage mean values were significantly (P<0.01) higher in 1.0% SL and 1.5% SL compared to control. These values were significantly (P<0.01) higher than in 0.5%, 2.0%, 2.5% and 3.0% SL. The mean values of post-thaw morphological normal sperm percentage did not differ between 1.0% SL and control groups but significantly (P<0.01) higher than 0.5%, 1.5%, 2.0%, 2.5% and 3.0% SL. The respective percentage mean values of post-thaw sperm with head, mid-piece and tail abnormalities were significantly (P<0.01) lower in 1.0% SL than all other SL concentrations. Concerning the post-thaw percentages of acrosome and sperm membrane integrity, the respective mean values were significantly (P<0.01) higher in 1.0% SL and 1.5% SL as compared to control. Mean values of both parameters in the 0.5% SL were intermediate between 1.0% and 1.5% SL versus control groups. The previously mentioned mean values in acrosome/membrane integrity were significantly (P<0.01) higher than 2.0% SL, 2.5% SL and 3.0% SL. Conclusions: Lecithin-based diluent can be a potent proper alternative extender for preservation of spermatozoa during pre- and post-freezing process. SL 1.5% extenders have supplied an optimal environment and condition for ameliorating the quality of pre-freezing and post-thaw buffalo spermatozoa by means of improved motility, viability, functional acrosome, sperm membrane integrity and morphologically normal spermatozoa

Genome-wide association study for systemic lupus erythematosus in an egyptian population

Systemic lupus erythematosus (SLE) susceptibility has a strong genetic component. Genome-wide association studies (GWAS) across trans-ancestral populations show both common and distinct genetic variants of susceptibility across European and Asian ancestries, while many other ethnic populations remain underexplored. We conducted the first SLE GWAS on Egyptians-an admixed North African/Middle Eastern population-using 537 patients and 883 controls. To identify novel susceptibility loci and replicate previously known loci, we performed imputation-based association analysis with 6,382,276 SNPs while accounting for individual admixture. We validated the association analysis using adaptive permutation tests (n = 109). We identified a novel genome-wide significant locus near IRS1/miR-5702 (Pcorrected = 1.98 × 10-8) and eight novel suggestive loci (Pcorrected &lt; 1.0 × 10-5). We also replicated (Pperm &lt; 0.01) 97 previously known loci with at least one associated nearby SNP, with ITGAM, DEF6-PPARD and IRF5 the top three replicated loci. SNPs correlated (r 2 &gt; 0.8) with lead SNPs from four suggestive loci (ARMC9, DIAPH3, IFLDT1, and ENTPD3) were associated with differential gene expression (3.5 × 10-95 &lt; p &lt; 1.0 × 10-2) across diverse tissues. These loci are involved in cellular proliferation and invasion-pathways prominent in lupus and nephritis. Our study highlights the utility of GWAS in an admixed Egyptian population for delineating new genetic associations and for understanding SLE pathogenesis