Investigating the mincing method for isolation of adipose-derived stem cells from pregnant women fat

The success of stem cell application in regenerative medicine, usually require a stable source of stem or progenitor cells. Fat tissue represents a good source of stem cells because it is rich in stem cells and there are fewer ethical issues related to the use of such stem cells, unlike embryonic stem cells. Therefore, there has been increased interest in adipose-derived stem cells (ADSCs) for tissue engineering applications. Here, we aim to provide an easy processing method for isolating adult stem cells from human adipose tissue harvested from the subcutaneous fat of the abdominal wall during gynecologic surgery. We used a homogenizer to mince fat and compared the results with those obtained from the traditional cut method involving a sterile scalpel and forceps. Our results showed that our method provides another stable and quality source of stem cells that could be used in cases with a large quantity of fat. Furthermore, we found that pregnancy adipose-derived stem cells (P-ADSCs) could be maintained in vitro for extended periods with a stable population doubling and low senescence levels. P-ADSCs could also differentiate in vitro into adipogenic, osteogenic, chondrogenic, and insulin-producing cells in the presence of lineage-specific induction factors. In conclusion, like human lipoaspirates, adipose tissues obtained from pregnant women contain multipotent cells with better proliferation and showed great promise for use in both stem cell banking studies as well as in stem cell therapy.     

Antheridiogen production and response in Polypodiaceae species

Antheridiogen chemicals secreted by living fern gametophytes have been shown to influence production of male gametangia and thus mating systems in a large number of terrestrial fern species. Antheridiogens have not previously been thought to be prevalent in the Polypodiaceae, a large family composed mostly of tropical epiphytes. This study presents bioassay methods more sensitive than previously used to detect antheridiogen and demonstrates that antheridiogens are also operative in the Polypodiaceae and in epiphytic species. Seven species in six genera (Campyloneurum angustifolium, C. phyllitidis, Lepisorus thunbergianus, Microgramma heterophylla, Phlebodium aureum, Phymatosorus scolopendria, and Polypodium pellucidum) were tested for the presence of an antheridiogen system. All species tested except P. aureum were induced to produce antheridia precociously by their own antheridiogen and by that of Pteridium aquilinum (APt). Phlebodium aureum responded to APt and promoted antheridium formation in Onoclea sensibilis but did not respond to its own antheridiogen. Spores of all species except P. aureum were induced to germinate in darkness by antheridiogen of the same species and by APt and to form antheridia in the dark, further enhancing the possibility of intergametophytic mating.     

Utilizing the macroporous media for insect cell/baculovirus expression

Due to their bio-compatibility and high porosity, cellulose foam and polyurethane foam (PUF) were selected as the media to immobilize insect cells for recombinant baculovirus expression. In packed beds, entrapment efficiency and axial cell distribution are two prime important parameters associated with reactor performance. These two parameters were found to be affected by initial cell loading density and liquid circulation rate. Based on the entrapment kinetic model, the entrapment parameters as K ₀, σ _m could be evaluated. The establishment of the correlation between K ₀, σ _m and Reynolds number, N _Re, described in this study provided convenient tools to achieve an efficient cell entrapment in the packed bed. The appropriated circulation velocity for uniform cell distribution was also determined.     

The use of egg chorion glycoprotein of Epinephelus malabaricus for egg identification

An immuno‐probe against a glycoprotein in the egg chorion was developed for egg identification. The 97 kD glycoprotein in the chorion of unfertilized eggs of Epinephelus malabaricus was isolated and separated by SDS‐PAGE as an antigen to induce antibody from rabbit. The reactivity of the antibody as the immuno‐probe to E. malabaricus eggs was significantly positive, and was specific in that it did not react with the eggs of other fish species. The immuno‐probe should be useful in identifying the eggs of E. malabaricus among mixed egg populations.     

Why we need mechanics to understand animal regeneration

Mechanical forces are an important contributor to cell fate specification and cell migration during embryonic development in animals. Similarities between embryogenesis and regeneration, particularly with regards to pattern formation and large-scale tissue movements, suggest similarly important roles for physical forces during regeneration. While the influence of the mechanical environment on stem cell differentiation in vitro is being actively exploited in the fields of tissue engineering and regenerative medicine, comparatively little is known about the role of stresses and strains acting during animal regeneration. In this review, we summarize published work on the role of physical principles and mechanical forces in animal regeneration. Novel experimental techniques aimed at addressing the role of mechanics in embryogenesis have greatly enhanced our understanding at scales from the subcellular to the macroscopic – we believe the time is ripe for the field of regeneration to similarly leverage the tools of the mechanobiological research community.     

Somaclonal variation does not preclude the use of rice transformants for genetic screening

Rice (Oryza sativa) is one of the world's most important crops. Rice researchers make extensive use of insertional mutants for the study of gene function. Approximately half a million flanking sequence tags from rice insertional mutant libraries are publicly available. However, the relationship between genotype and phenotype is very weak. Transgenic plant assays have been used frequently for complementation, overexpression or antisense analysis, but sequence changes caused by callus growth, Agrobacterium incubation medium, virulence genes, transformation and selection conditions are unknown. We used high‐throughput sequencing of DNA from rice lines derived from Tainung 67 to analyze non‐transformed and transgenic rice plants for mutations caused by these parameters. For comparison, we also analyzed sequence changes for two additional rice varieties and four T‐DNA tagged transformants from the Taiwan Rice Insertional Mutant resource. We identified single‐nucleotide polymorphisms, small indels, large deletions, chromosome doubling and chromosome translocations in these lines. Using standard rice regeneration/transformation procedures, the mutation rates of regenerants and transformants were relatively low, with no significant differences among eight tested treatments in the Tainung 67 background and in the cultivars Taikeng 9 and IR64. Thus, we could not conclusively detect sequence changes resulting from Agrobacterium‐mediated transformation in addition to those caused by tissue culture‐induced somaclonal variation. However, the mutation frequencies within the two publically available tagged mutant populations, including TRIM transformants or Tos17 lines, were about 10‐fold higher than the frequency of standard transformants, probably because mass production of embryogenic calli and longer callus growth periods were required to generate these large libraries.