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Patient-specific, immune-matched human embryonic stem cells (hESCs) are anticipated to be of great biomedical importance for studies of disease and development and to advance clinical deliberations regarding stem cell transplantation. Eleven hESC lines were established by somatic cell nuclear transfer (SCNT) of skin cells from patients with disease or injury into donated oocytes. These lines, nuclear transfer (NT)–hESCs, grown on human feeders from the same NT donor or from genetically unrelated individuals, were established at high rates, regardless of NT donor sex or age. NT-hESCs were pluripotent, chromosomally normal, and matched the NT patient's DNA. The major histocompatibility complex identity of each NT-hESC when compared to the patient's own showed immunological compatibility, which is important for eventual transplantation. With the generation of these NT-hESCs, evaluations of genetic and epigenetic stability can be made. Additional work remains to be done regarding the development of reliable directed differentiation and the elimination of remaining animal components. Before clinical use of these cells can occur, preclinical evidence is required to prove that transplantation of differentiated NT-hESCs can be safe, effective, and tolerated.

Novel meso−meso directly linked porphyrin dimers tethered at β-pyrrolic positions of the porphyrin ring with 2-propenoic acids or 2,4-pentadienoic acids were prepared for sensitization of nanocrystalline titanium dioxide solar cells. Most importantly, the absorption spectra of dimeric porphyrins were notably extended into the midvisible region in the solar spectrum while the LUMO levels are sufficiently high to inject electrons to the conduction band of TiO2. Among these dimers, PEG-2b-bd-Zn2 dimer, bearing a poly(ethylene glycol) end group at one meso position, showed the highest incident photon-to-photocurrent generation with 47% efficiency at the Soret region as well as the power conversion efficiency of 4.2% under standard AM 1.5 solar condition. To elucidate electronic structures and excited-state properties, UV−vis absorption and emission, cyclic voltammetry measurements, and density functional theory calculations were performed. To our best knowledge, the obtained conversion efficiency of 4.2% from PEG-2b-bd-Zn2-sensitized DSSC is the highest photovoltaic performance among DSSCs based on oligomeric porphyrins. Thus, this work suggests that the wide spectral response of directly linked porphyrin dimers due to the excitonic coupling is an intriguing aspect of directly linked pophyrin dimers to be utilized for DSSCs and gives an insight into the design of more efficient light-harvesting molecules.

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In an effort to improve the quality of in vitro produced porcine embryos, we investigated the effect of brain-derived neurotropic factor (BDNF), a neurotropin family member, on in vitro maturation (IVM) of porcine oocytes. The expression of BDNF and truncated isoforms of its receptor, tyrosine kinase B (TrkB), and p75 common neurotropin receptor was detected in both follicular cells and metaphase-I stage oocytes by RT-PCR. However, mRNA of full-length TrkB was not found in oocytes although it was detected in follicular cells. The expression pattern of BDNF and TrkB was confirmed by immunohistochemistry. Supplementation with BDNF (30 ng/ml) during IVM significantly (P!0.05) increased the first polar body extrusion and glutathione levels in oocytes, whereas the effect of BDNF on nuclear maturation was diminished when gonadotropin and epidermal growth factor (EGF) were added to the culture media. However, treatment with BDNF (30 ng/ml) along with EGF (10 ng/ml) in the presence of gonadotropin significantly (P!0.05) increased the developmental competence of oocytes to the blastocyst stage after both in vitro fertilization (IVF; 29.1% when compared with control, 15.6%) and somatic cell nuclear transfer (SCNT; 13.6% when compared with control, 3%). This appeared to reflect a stimulatory interaction between BDNF and EGF to enhance the cytoplasmic maturation of oocytes to support successful preimplantation development. In conclusion, BDNF enhanced nuclear and cytoplasmic maturation of oocytes by autocrine and/or paracrine signals. Also, when used together with EGF, BDNF increased the developmental potency of embryos after IVF and SCNT, demonstrating an improved in vitro production protocol for porcine oocytes.

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