Two TPB-based HTMs were synthesized and their energy levels were tuned to match with perovskite by introducing electron-donating groups asymmetrically. The TPBC based doping-free perovskite solar cell afforded an impressive PCE of 13.10% under AM 1.5G illumination, which is the first case of an effective device with TPB-based doping-free HTMs.

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Heat stress will stimulate cells of living organisms to generate heat shock proteins (Hsps). In the mouse liver, impacts of heat stress on hepatocyte proliferation, apoptosis and metabolism have not been studied systematically at different temperatures. In this research, the test mice were heated to 40, 42, 44 and 46°C, respectively, for 20 min and recovered at room temperature for 8 h in normal feeding conditions; the control animals were kept at room temperature without heat stress. The expression levels of Hsp70, Pcna, Bax, Bcl2, cytochrome P450 1A2 (CYP1A2), CYP2E1 and analog of CYP3A4 (not reported in mouse before), the parameters reflecting stress strength, cell proliferation, apoptosis and metabolism, were detected by western blotting, immunohistochemistry and semi-quantitative RT-PCR in test and control mice. Haematoxylin-eosin (H&E) staining and TUNEL analysis were further used to study the impacts of heat stress at different temperatures on hepatocellular necrosis and apoptosis. Serum AST and ALT levels, the markers of liver injury, were measured after heat stress at different temperatures. The data show that Hsp70 expression was significantly increased when temperature increased (P < 0.05). At lower temperatures (40 or 42°C), expression of Pcna, CYP1A2 and analog of CYP3A4 were considerably increased (P < 0.05) while hepatocyte necrosis and apoptosis were not induced (P > 0.05). At higher temperatures (44 or 46°C), expression of Pcna was decreased while hepatocyte necrosis and apoptosis were induced (P < 0.05). Expressions of CYP1A2 and analog of CYP3A4 were decreased especially at 46°C (P < 0.05). Expression of CYP2E1 could not be detected to increase at 40°C but was at high levels at 42, 44 and 46°C (P < 0.05). Expressions of AST and ALT were not different between the test mice and control mice at 40°C while they were significantly higher in the test mice than those in the control mice at 42 (P < 0.05), 44 and 46°C (P < 0.01). In conclusion, heat stress at lower temperatures promotes hepatocyte proliferation and improves the metabolic efficiency in mouse liver while heat stress at higher temperatures inhibits hepatocyte proliferation, promotes hepatocyte apoptosis and induces hepatocyte necrosis. This may give a hint to understanding human liver injury in high temperatures. Moreover, it is the first time that the analog of CYP3A4 was detected in mouse hepatocellular cytoplasm. It is worthwhile to dissect its function in future work.

To investigate the effect of mitochondrial heteroplasmy on embryo development, cloned embryos produced using bovine oocytes as the recipient cytoplasm and ovine granulosa cells as the donor nuclei were complemented with 2pL mitochondrial suspension isolated from ovine (BOOMT embryos) or bovine (BOBMT embryos) granulosa cells; cloned embryos without mitochondrial injection served as the control group (BO embryos). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and sodium bisulfite genomic sequencing were used to analyse mRNA and methylation levels of pluripotency genes (OCT4, SOX2) and mitochondrial genes (TFAM, POLRMT) in the early developmental stages of cloned embryos. The number of mitochondrial DNA copies in 2pL ovine-derived and bovine-derived mitochondrial suspensions was 960±110 and 1000±120, respectively. The blastocyst formation rates were similar in BOBMT and BO embryos (P>0.05), but significantly higher than in BOOMT embryos (P<0.01). Expression of OCT4 and SOX2, as detected by RT-qPCR, decreased significantly in BOOMT embryos (P<0.05), whereas the expression of TFAM and POLRMT increased significantly, compared with expression in BOOMT and BO embryos (P<0.05). In addition, methylation levels of OCT4 and SOX2 were significantly greater (P<0.05), whereas those of TFAM and POLRMT were significantly lower (P<0.01), in BOOMT embryos compared with BOBMT and BO embryos. Together, the results of the present study suggest that the degree of mitochondrial heteroplasmy may affect embryonic development.