Differentiation Induction of Human Stem Cells for Corneal Epithelial Regeneration.

Deficiency of corneal epithelium causes vision impairment or blindness in severe cases. Transplantation of corneal epithelial cells is an effective treatment but the availability of the tissue source for those cells is inadequate. Stem cells can be induced to differentiate to corneal epithelial cells and used in the treatment. Multipotent stem cells (mesenchymal stem cells) and pluripotent stem cells (embryonic stem cells and induced pluripotent stem cells) are promising cells to address the problem. Various protocols have been developed to induce differentiation of the stem cells into corneal epithelial cells. The feasibility and efficacy of both human stem cells and animal stem cells have been investigated for corneal epithelium regeneration. However, some physiological aspects of animal stem cells are different from those of human stem cells, the protocols suited for animal stem cells might not be suitable for human stem cells. Therefore, in this review, only the investigations of corneal epithelial differentiation of human stem cells are taken into account. The available protocols for inducing the differentiation of human stem cells into corneal epithelial cells are gathered and compared. Also, the pathways involving in the differentiation are provided to elucidate the relevant mechanisms.

Development of Lipid-Based Nanocarriers for Increasing Gastrointestinal Absorption of Lupinifolin.

Lupinifolin, a plant flavonoid, has been reported to possess various pharmacological effects. It most likely exerts low oral bioavailability because of poor water solubility. The objective of this study was to develop lipid nanocarriers as drug delivery systems to increase the gastrointestinal absorption of lupinifolin extracted from Albizia myriophylla. Three types of nanocarriers, lupinifolin-loaded solid lipid nanoparticles, lupinifolin-loaded nanostructured lipid carriers, and lupinifolin-loaded nanoemulsions, were prepared by an emulsification-sonication technique. All three types of nanocarriers loaded with lupinifolin, lupinifolin-loaded solid lipid nanoparticles, lupinifolin-loaded nanostructured lipid carriers, and lupinifolin-loaded nanoemulsions, were successfully synthesized. The lipid components chosen to formulate nanocarriers were tripalmitin and/or medium chain triglyceride. Physicochemical characterizations along with releasing profiles of lupinifolin-loaded lipid nanocarriers were compared. It was found that the best lipid nanocarrier for lupinifolin was lupinifolin-loaded nanostructured lipid carriers, which demonstrated the particle size of 151.5 ± 0.1 nm, monodispersity distribution with a polydispersity index of 0.24, negative surface charge at - 41.2 ± 0.7 mV, high encapsulation (99.3%), and high loading capacity (5.0%). The obtained lupinifolin-loaded nanostructured lipid carriers exhibited prolonged release in a simulated circulatory system but produced a low release in gastrointestinal conditions (3.7%). Intestinal permeability of the nanocarriers was further evaluated in everted intestinal sacs. The results from the ex vivo study indicated that lupinifolin-loaded nanostructured lipid carriers significantly increased the absorption of lupinifolin compared to the native form. In conclusion, lupinifolin-loaded lipid nanocarriers were successfully formulated as delivery systems to enhance its oral bioavailability. Further in vivo experiments are needed to validate the results from this study.

Live sharksucker Echeneis naucrates (Linnaeus 1758) mitochondrial genome: the first report of Echeneidae complete mitochondrial genome.

The complete mitochondrial genome of Echeneis naucrates is 16,611 bp in length. It comprises a control region, 13 protein-coding genes, 2 ribosomal RNAs (rRNAs) and 22 transfer RNAs (tRNAs), with an arrangement typical of vertebrate mitochondrial genomes. Base composition on the heavy strand is 30.24% A, 25.45% C, 15.02% G and 29.29% T. The control region is 940 bp in length, containing putative termination associated sequences (TASs) and conserved sequence blocks (CSBs). Two copies of a tandem repeat (AATATTAT) were found in all six individuals investigated. The hypothesis of selection for an optimal number of repeats as well as the evolutionary dynamics of tandem repeats in E. naucrates control regions await further investigations.

Reanalysis and revision of the complete mitochondrial genome of Rachycentron canadum (Teleostei, Perciformes, Rachycentridae).

The complete mitochondrial genome of cobia, Rachycentron canadum, was reanalyzed and revised. The genome is 18,008 bp in length, containing 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a control region or displacement loop (D-loop). The gene arrangement is identical to that observed in most vertebrates. Base composition on the heavy strand is 30.14% A, 25.22% C, 15.80% G and 28.84% T. The D-loop region exhibits an A + T rich pattern, containing short tandem repeats of TATATACATGG, TATATGCACAA and TATATGCACGG. The mitochondrial genome studied differs from the previously published genome in two segments; the control region to 12S and ND5 to tRNA(Glu). The 12S sequence also differs from those published in the databases. Phylogeny analyses revealed that the differences could be due to errors in sequence assembly and/or sample misidentification of the previous studies.