Estrogen is an active neuroprotectant and is presently investigated as a potential therapy against Alzheimer's disease for women. To determine if male hormones could also be neuroprotective, we investigated the effect of testosterone, methyltestosterone, and epitestosterone at physiological concentrations on primary cultures of human neurons induced to undergo apoptosis by serum deprivation. Serum deprivation signi®cantly induces neuronal apoptosis in a protracted fashion. As expected, physiological concentrations of 17-bestradiol and transcriptionally inactive 17-a-estradiol protect neurons against apoptosis. Similar to 17-b-estradiol, physiological concentrations of testosterone are also neuroprotective. Androgen receptors are present at 8^2 fmol/mg protein in the neuron cultures. The non-aromatizable androgen, mibolerone, is also neuroprotective and aromatase inhibitor, 4-androsten-4-OL-3,17-dione, does not prevent testosteronemediated neuroprotection. In contrast, anti-androgen,¯utamide, eliminates testosterone-mediated neuroprotection. Testosterone analog, methyltestosterone, showed androgen receptordependent neuroprotection that was delayed in time indicating that a metabolite may be the active agent. The endogenous anti-androgen, epitestosterone, also showed a slight neuroprotective effect but not through the androgen receptor. These results indicate that androgens induce neuroprotection directly through the androgen receptor. These data suggest that androgens may also be of therapeutic value against Alzheimer's disease in aging males.

Cytoplasmic microinjection (CI) of the CRISPR/Cas9 system enabled the induction of site-specific mutations in porcine zygotes and resulting pigs. However, mosaicism is a serious problem for genetically modified pigs. In the present study, we investigated suitable timing and concentration of CRISPR/Cas9 components for introduction into oocytes/zygotes by CI, to reduce mosaicism in the resulting blastocysts. First, we introduced 20 ng/μl of Cas9 protein and guide RNA (gRNA), targeting the α-1,3-galactosyltransferase ( GalT ) gene in oocytes before in vitro fertilization (IVF), in zygotes after IVF, or in oocytes/zygotes before and after IVF, twice. CI treatment had no detrimental effects on blastocyst formation rates. The highest value of the rate of mutant blastocysts was observed in zygotes injected after IVF. Next, we injected Cas9 protein and gRNA into zygotes after IVF at a concentration of 20 ng/μl each (20 ng/μl group) or 100 ng/μl each (100 ng/μl group). The ratio of the number of blastocysts that carried mutations to the total number of blastocysts examined in the 100 ng/μl group was significantly higher (P < 0.05) than that in the 20 ng/μl group. Although no blastocysts from the 20 ng/μl group carried a biallelic mutation, 16.7% of blastocysts from the 100 ng/μl group carried a biallelic mutation. In conclusion, increasing the concentration of Cas9 protein and gRNA is effective in generating biallelic mutant blastocysts. To reduce mosaicism, however, further optimization of the timing of CI, and the concentration of CRISPR/Cas9 components, is needed.

TP53 (which encodes p53) is one of the most frequently mutated genes in cancers. In this study, we generated TP53-mutant pigs by gene editing via electroporation of the Cas9 protein (GEEP), a process that involves introducing the Cas9 protein and single-guide RNA (sgRNA) targeting exon 3 and intron 4 of TP53 into in vitro-fertilized zygotes. Zygotes modified by the sgRNAs were transferred to recipients, two of which gave birth to a total of 11 piglets. Of those 11 piglets, 9 survived. Molecular genetic analysis confirmed that 6 of 9 live piglets carried mutations in TP53, including 2 piglets with no wild-type (WT) sequences and 4 genetically mosaic piglets with WT sequences. One mosaic piglet had 142 and 151 bp deletions caused by a combination of the two sgRNAs. These piglets were continually monitored for 16 months and three of the genome-edited pigs (50%) exhibited various tumor phenotypes that we presumed were caused by TP53 mutations. Two mutant pigs with no WT sequences developed mandibular osteosarcoma and nephroblastoma. The mosaic pig with a deletion between targeting sites of two sgRNAs exhibited malignant fibrous histiocytoma. Tumor phenotypes of TP53 mosaic mutant pigs have not been previously reported. Our results indicated that the mutations caused by gene editing successfully induced tumor phenotypes in both TP53 mosaic- and bi-allelic mutant pigs.

The overspread of the novel coronavirus—SARS-CoV-2—over the globe has caused significant damage to manufacturing and service businesses, regardless of whether they are commercial, public, or not-for-profit sectors. While both the short-term and long-term impacts of most companies can be approximately measured or estimated, it is challenging to address the enduring effects of COVID-19 on teaching and learning activities. The target of this research is to investigate students’ manners of studying at home during the school suspension time as a result of COVID-19. Through analyzing original survey data from 420 K6–12 students in Hanoi, Vietnam, this work demonstrates the different learning habits of students with different socioeconomic statuses and occupational aspirations during the disease’s outbreak. In particular, we featured the differences in students’ learning behaviours between private schools and public schools, as well as between students who plan to follow STEM-related careers and those who intend to engage in social science-related careers. The empirical evidence of this study can be used for the consideration of the local government to increase the sustainability of coming policies and regulations to boost students’ self-efficacy, as it will affect 1.4 million students in Hanoi, as well as the larger population of nearly 10 million Vietnamese students. These results can also be the foundation for future investigations on how to elevate students’ learning habits toward Sustainable Development Goal 4 (SDG4)— Quality Education—especially in fanciful situations in which the regular school operation has been disrupted, counting with limited observation and support from teachers and parents.

Genetically modified animal models play an important role in elucidating pathogenesis and developing therapeutic strategies for human diseases. Pigs are considered one of the best animal models because their anatomy and physiology are similar to those of humans (Fan & Lai, 2013; Niemann & Lucas-Hahn, 2012). Clustered regularly interspaced short palindromic repeat (CRISPR) and CRISPR-associated protein 9 (Cas9) are part of a genome engineering method based on the bacterial CRISPR immune system and have been developed and widely used for gene editing to produce genetically modified pigs (Wang, Du, et al., 2015; Yu et al., 2016). In these previous studies, modern techniques, such as somatic cell nuclear transfer (SCNT) and microinjection for the production of genetically modified pigs were used. Recently,