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Instead of asking whether money matters, this paper questions whose money matters in public education. Previous literature on education funding uses an aggregate expenditure per pupil to measure the relationship between education funding and academic performance. Federalism creates mainly three levels of funding sources: federal, state, and local governments. Examining New York State school districts, most equitably funded across school districts among the 50 states, this paper shows that neither federal nor state funds are positively correlated with graduation rates. Only local revenues for school districts indicate a strong positive impact. Parents' money matters. This finding contributes to a contentious discourse on education funding policy in the governments, courts, and academia with respect to education funding and inequality in American public schools.

The reflection and refraction of light are more familiar to students than the reflection and refraction of sound. Reflection and refraction that occur during the transmission of sound waves are common phenomena in everyday life but are often difficult to understand during actual learning. In this study, we developed a sound reflection and refraction test apparatus that can measure sound's reflection and refraction angles by injecting sound using a super directional speaker with excellent straightness. Consequently, moving the sound sensor made it possible to find a point with high sound pressure and measure the sound's reflection and refraction angles. Since this device is similar to the experimental device that measures the angle of reflection and refraction of light, it is expected to be able to phenomenologically compare and confirm the reflection and refraction paths of light and sound.

Embryonic stem cells (ESC) hold promise for the treatment of human medical conditions but are allogeneic. Here, we consider the differences between autologous pluripotent stem cells produced by nuclear transfer (NT-ESCs) and transcription factor-mediated, induced pluripotent stem cells (iPSCs) that impact the desirability of each of these cell types for clinical use. The derivation of NT-ESCs is more cumbersome and requires donor oocytes; however, the use of oocyte cytoplasm as the source of reprogramming factors is linked to a key advantage of NT-ESCs-the ability to replace mutant mitochondrial DNA in a patient cell (due to either age or inherited disease) with healthy donor mitochondria from an oocyte. Moreover, in epigenomic and transcriptomic comparisons between isogenic iPSCs and NT-ESCs, the latter produced cells that more closely resemble bona fide ESCs derived from fertilized embryos. Thus, although NT-ESCs are more difficult to generate than iPSCs, the ability of somatic cell nuclear transfer to replace aged or diseased mitochondria and the closer epigenomic and transcriptomic similarity between NT-ESCs and bona fide ESCs may make NT-ESCs superior for future applications in regenerative medicine. Stem Cells 2017;35:26-34.

Vertebrate cells carry two different genomes, nuclear (nDNA) and mitochondrial (mtDNA), both encoding proteins involved in oxidative phosphorylation. Because of the extensive interactions, adaptive coevolution of the two genomes must occur to ensure normal mitochondrial function. To investigate whether incompatibilities between these two genomes could contribute to interspecies reproductive barriers, we performed reciprocal mtDNA replacement (MR) in zygotes between widely divergent Mus m. domesticus (B6) and conplastic Mus m. musculus (PWD) mice. Transfer of MR1 cybrid embryos (B6nDNA-PWDmtDNA) supported normal development of F1 offspring with reduced male fertility but unaffected reproductive fitness in females. Furthermore, donor PWD mtDNA was faithfully transmitted through the germline into F2 and F3 generations. In contrast, reciprocal MR2 (PWDnDNA-B6mtDNA) produced high embryonic loss and stillborn rates, suggesting an association between mitochondrial function and infertility. These results strongly suggest that functional incompatibility between nuclear and mitochondrial genomes contributes to interspecies reproductive isolation in mammals.

Mitochondria have a major role in energy production via oxidative phosphorylation, which is dependent on the expression of critical genes encoded by mitochondrial (mt)DNA. Mutations in mtDNA can cause fatal or severely debilitating disorders with limited treatment options. Clinical manifestations vary based on mutation type and heteroplasmy (that is, the relative levels of mutant and wild-type mtDNA within each cell). Here we generated genetically corrected pluripotent stem cells (PSCs) from patients with mtDNA disease. Multiple induced pluripotent stem (iPS) cell lines were derived from patients with common heteroplasmic mutations including 3243A>G, causing mitochondrial encephalomyopathy and stroke-like episodes (MELAS), and 8993T>G and 13513G>A, implicated in Leigh syndrome. Isogenic MELAS and Leigh syndrome iPS cell lines were generated containing exclusively wild-type or mutant mtDNA through spontaneous segregation of heteroplasmic mtDNA in proliferating fibroblasts. Furthermore, somatic cell nuclear transfer (SCNT) enabled replacement of mutant mtDNA from homoplasmic 8993T>G fibroblasts to generate corrected Leigh-NT1 PSCs. Although Leigh-NT1 PSCs contained donor oocyte wild-type mtDNA (human haplotype D4a) that differed from Leigh syndrome patient haplotype (F1a) at a total of 47 nucleotide sites, Leigh-NT1 cells displayed transcriptomic profiles similar to those in embryo-derived PSCs carrying wild-type mtDNA, indicative of normal nuclear-to-mitochondrial interactions. Moreover, genetically rescued patient PSCs displayed normal metabolic function compared to impaired oxygen consumption and ATP production observed in mutant cells. We conclude that both reprogramming approaches offer complementary strategies for derivation of PSCs containing exclusively wild-type mtDNA, through spontaneous segregation of heteroplasmic mtDNA in individual iPS cell lines or mitochondrial replacement by SCNT in homoplasmic mtDNA-based disease.

Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although embryonic stem cells (ES cells) from in vitro fertilized embryos (IVF ES cells) represent the 'gold standard', they are allogeneic to patients. Autologous induced pluripotent stem cells (iPS cells) are prone to epigenetic and transcriptional aberrations. To determine whether such abnormalities are intrinsic to somatic cell reprogramming or secondary to the reprogramming method, genetically matched sets of human IVF ES cells, iPS cells and nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT) were subjected to genome-wide analyses. Both NT ES cells and iPS cells derived from the same somatic cells contained comparable numbers of de novo copy number variations. In contrast, DNA methylation and transcriptome profiles of NT ES cells corresponded closely to those of IVF ES cells, whereas iPS cells differed and retained residual DNA methylation patterns typical of parental somatic cells. Thus, human somatic cells can be faithfully reprogrammed to pluripotency by SCNT and are therefore ideal for cell replacement therapies.

Allogeneic natural killer (NK) cell therapy has been effective in treating cancer. Many studies have tested NK cell therapy using human pluripotent stem cells (hPSCs). However, the impacts of the origin of PSC-NK cells on competence are unclear. In this study, several types of hPSCs, including human-induced PSCs (hiPSCs) generated from CD34+, CD3−CD56+, and CD56− cells in umbilical cord blood (UCB), three lines of human embryonic stem cells (hESCs, ES-1. ES-2 and ES-3) and MHC I knockout (B2M-KO)-ESCs were used to differentiate into NK cells and their capacities were analyzed. All PSC types could differentiate into NK cells. Among the iPSC-derived NK cells (iPSC-NKs) and ESC-derived NK cells (ES-NKs), 34+ iPSCs and ES-3 had a higher growth rate and cytotoxicity, respectively, ES-3 also showed better efficacy than 34+ iPSCs. B2M-KO was similar to the wild type. These results suggest that the screening for differentiation of PSCs into NK cells prior to selecting the PSC lines for the development of NK cell immunotherapy is an essential process for universal allotransplantation, including the chimeric antigen receptor (CAR). [ABSTRACT FROM AUTHOR]

Author(s): Eunju Kang [sup.1] [sup.2] [sup.12] , Jun Wu [sup.3] , Nuria Marti Gutierrez [sup.1] [sup.2] , Amy Koski [sup.1] [sup.2] , Rebecca Tippner-Hedges [sup.1] [sup.2] , Karen Agaronyan [sup.4] [...], Change history In this Letter, there are several errors regarding the assignments of mtDNA haplotypes for a subset of egg donors from our study. These errors have not been corrected online.

Visual images are widely used in science textbooks to facilitate the understanding of abstract concept of light. This study aims to compare and analyze elementary school textbooks from Korea, the United States, and Japan, focusing on how visual images are utilized to effectively convey light-related content. The findings reveal that all three countries' textbooks predominantly employ photographs as visual representations, primarily serving the purpose of providing data. Through a social semiotic perspective analysis, it was observed that science textbooks commonly utilize realistic images with metaphorical functions, presented at eye level angles, with intermediate distances, and frontal angles. Furthermore, the visual images employed various colors and background expressions to create a sense of familiarity for students. These findings suggest that the composition of visual images in science textbooks was designed to facilitate an easy understanding of light-related concepts. [ABSTRACT FROM AUTHOR]

We studied messenger RNA expression levels and cellular localization of several maternal and embryonic factors in unfertilized oocytes andpre-implantation-stage embryos (9-13), namely, Hsf1, Brg1, Bmi1 (also known as Smarca4), Oct4 [...], Successful mammalian cloning using somatic cell nuclear transfer (SCNT) into unfertilized, metaphase II (MII)-arrested oocytes attests to the cytoplasmic presence of reprogramming factors capable of inducing totipotency in somatic cell nuclei (1-3). However, these poorly defined maternal factors presumably decline sharply after fertilization, as the cytoplasm of pronuclear-stage zygotes is reportedly inactive (4,5). Recent evidence suggests that zygotic cytoplasm, if maintained at metaphase, can also support derivation of embryonic stem (ES) cells after SCNT (6-8), albeit at low efficiency. This led to the conclusion that critical oocyte reprogramming factors present in the metaphase but not in the interphase cytoplasm are 'trapped' inside the nucleus during interphase and effectively removed during enucleation (9). Here we investigated the presence of reprogramming activity in the cytoplasm of interphase two-cell mouse embryos (I2C). First, the presence of candidate reprogramming factors was documented in both intact and enucleated metaphase and interphase zygotes and twocell embryos. Consequently, enucleation did not provide a likely explanation for the inability of interphase cytoplasm to induce reprogramming. Second, when we carefully synchronized the cell cycle stage between the transplanted nucleus (ES cell, fetal fibroblast or terminally differentiated cumulus cell) and the recipient I2C cytoplasm, the reconstructed SCNT embryos developed into blastocysts and ES cells capable of contributing to traditional germline and tetraploid chimaeras. Last, direct transfer of cloned embryos, reconstructed with ES cell nuclei, into recipients resulted in live offspring. Thus, the cytoplasm of I2C supports efficient reprogramming, with cell cycle synchronization between the donor nucleus and recipient cytoplasm as the most critical parameter determining success. The ability to use interphase cytoplasm in SCNT could aid efforts to generate autologous human ES cells for regenerative applications, as donated or discarded embryos are more accessible than unfertilized MII oocytes.

Corneal endothelial cells (CECs) do not proliferate or recover after illness or injury, resulting in decreased cell density and loss of pump/barrier function. Considering the shortage of donor cornea, it is vital to establish robust methods to generate CECs from induced pluripotent stem cells (iPSCs). We investigated the efficacy and safety of transplantation of iPSC-derived CECs into a corneal endothelial dysfunction (CED) rabbit model. iPSCs were generated from human fibroblasts. We characterized iPSCs by demonstrating the gene expression of the PSC markers OCT4, SOX2, TRA-1-60, and NANOG, teratoma formation, and differentiation into three germ layers. Differentiation of iPSCs into CECs was induced via neural crest cell (NCC) induction. CEC markers were detected using immunofluorescence and gene expression was analyzed using quantitative real-time PCR (qRT-PCR). After culturing iPSC-derived NCCs, we found the expression of zona occludens-1 (ZO-1) and Na+/K+ ATPase and a hexagonal morphology. ATP1A1, COL8A1, and AQP1 mRNA expression was higher in iPSC-derived CECs than in iPSCs and NCCs. We performed an injection of iPSC-derived CECs into the anterior chamber of a CED rabbit model and found improved levels of corneal transparency. We also found increased numbers of ZO-1- and ATP1A1-positive cells in rabbit corneas in the iPSC-derived CEC transplantation group. Usage of the coating material vitronectin (VTN) and fasudil resulted in good levels of CEC marker expression, demonstrated with Western blotting and immunocytochemistry. Combination of the VTN coating material and fasudil, instead of FNC mixture and Y27632, afforded the best results in terms of CEC differentiation's in vitro and in vivo efficacy. Successful transplantation of CEC-like cells into a CED animal model confirms the therapeutic efficacy of these cells, demonstrated by the restoration of corneal clarity. Our results suggest that iPSC-derived CECs can be a promising cellular resource for the treatment of CED. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA is localized in the cell's cytoplasm, whereas chromosomal genes are confined to the nucleus. Each cell may have thousands of mtDNA copies, which may all be mutated (homoplasmy) [...], Mutations in mitochondrial DNA (mtDNA) are associated with severe human diseases and are maternally inherited through the egg's cytoplasm. Here we investigated the feasibility of mtDNA replacement in human oocytes by spindle transfer (ST; also called spindle-chromosomal complex transfer). Of 106 human oocytes donated for research, 65 were subjected to reciprocal ST and 33 served as controls. Fertilization rate in ST oocytes (73%) was similar to controls (75%); however, a significant portion of ST zygotes (52%) showed abnormal fertilization as determined by an irregular number of pronuclei. Among normally fertilized ST zygotes, blastocyst development (62%) and embryonic stem cell isolation (38%) rates were comparable to controls. All embryonic stem cell lines derived from ST zygotes had normal euploid karyotypes and contained exclusively donor mtDNA. The mtDNA can be efficiently replaced in human oocytes. Although some ST oocytes displayed abnormal fertilization, remaining embryos were capable of developing to blastocysts and producing embryonic stem cells similar to controls.

Author(s): Hong Ma [1]; Nuria Marti-Gutierrez [1]; Sang-Wook Park [2]; Jun Wu [3]; Yeonmi Lee [1]; Keiichiro Suzuki [3]; Amy Koski [1]; Dongmei Ji [1]; Tomonari Hayama [1]; Riffat Ahmed [...], Genome editing has potential for the targeted correction of germline mutations. Here we describe the correction of the heterozygous MYBPC3 mutation in human preimplantation embryos with precise CRISPRCas9-based targeting accuracy and high homology-directed repair efficiency by activating an endogenous, germline-specific DNA repair response. Induced double-strand breaks (DSBs) at the mutant paternal allele were predominantly repaired using the homologous wild-type maternal gene instead of a synthetic DNA template. By modulating the cell cycle stage at which the DSB was induced, we were able to avoid mosaicism in cleaving embryos and achieve a high yield of homozygous embryos carrying the wild-type MYBPC3 gene without evidence of off-target mutations. The efficiency, accuracy and safety of the approach presented suggest that it has potential to be used for the correction of heritable mutations in human embryos by complementing preimplantation genetic diagnosis. However, much remains to be considered before clinical applications, including the reproducibility of the technique with other heterozygous mutations.