モンゴル ニ オケル ショチュウトウ キョウイク キカン ムケ ニホンゴ キョウカショ ノ カイハツ -プロフィシェンシー ジュウシ ト ジリツ ガクシュウ シエン ヘノ トリクミ-

モンゴルでは初中等段階の日本語学習者が全体の約7割を占めるに至っているが、初中等教育全体で統一したシラバスや教材がない。そこでモンゴル日本語教師会は「初中等教育機関向け日本語教科書作成プロジェクト」を実施し、モンゴル日本語教育スタンダードと共に教科書シリーズ『にほんご できるモン』を開発することとした。同スタンダードの理念は(1)社会の中で自分の考えを自由に表現し、相互理解するのに必要な外国語能力の育成、(2)子供たちが自分自身の力で学習を進めていく能力の育成であり、教科書にはプロフィシェンシー重視と自律学習支援の2つの特徴がある。新教科書を使用する教師とのやり取りから教科書が改善でき、学習者自身も話す能力の向上を感じているという報告を聞くが、一方で、教師には「書くことが学習である」という従来からのビリーフがあり、教科書が変わっても新しい教え方にならない等の課題が残っている。About 70% of Japanese-language learners in Mongolia are students in elementary and secondary schools. No standardized syllabus or teaching materials currently exist for these schools. Mongolia Japanese-language Teachers Association organized a project to develop Japanese-language textbooks for elementary and secondary schools. The association created a textbook series called "Nihongo Dekirumon", to accompany Mongolia Japanese-language education standard. The standard has two principles; 1) to foster foreign language proficiency needed to express free ideas in the society to achieve mutual understandings, 2) to foster the abilities to self-learning. The textbook series, therefore, has two features to account for proficiency and support learners\u27 autonomy. Discussions with teachers who used the trial edition of these books led to improvement of the books, and the students who used the books perceived the improvement of their speaking abilities. However, we found that most teachers have traditional teaching beliefs that "writing is learning", which hinders their adoption of the new standard. The change of textbooks is not designed to change their ways of teaching, which is our next issue to solve

In Vitro Spermatogenesis in Explanted Adult Mouse Testis Tissues.

Research on in vitro spermatogenesis is important for elucidating the spermatogenic mechanism. We previously developed an organ culture method which can support spermatogenesis from spermatogonial stem cells up to sperm formation using immature mouse testis tissues. In this study, we examined whether it is also applicable to mature testis tissues of adult mice. We used two lines of transgenic mice, Acrosin-GFP and Gsg2-GFP, which carry the marker GFP gene specific for meiotic and haploid cells, respectively. Testis tissue fragments of adult GFP mice, aged from 4 to 29 weeks old, which express GFP at full extension, were cultured in medium supplemented with 10% KSR or AlbuMAX. GFP expression decreased rapidly and became the lowest at 7 to 14 days of culture, but then slightly increased during the following culture period. This increase reflected de novo spermatogenesis, confirmed by BrdU labeling in spermatocytes and spermatids. We also used vitamin A-deficient mice, whose testes contain only spermatogonia. The testes of those mice at 13-21 weeks old, showing no GFP expression at explantation, gained GFP expression during culturing, and spermatogenesis was confirmed histologically. In addition, the adult testis tissues of Sl/Sld mutant mice, which lack spermatogenesis due to Kit ligand mutation, were cultured with recombinant Kit ligand to induce spermatogenesis up to haploid formation. Although the efficiency of spermatogenesis was lower than that of pup, present results showed that the organ culture method is effective for the culturing of mature adult mouse testis tissue, demonstrated by the induction of spermatogenesis from spermatogonia to haploid cells

Genome Editing in Mouse Spermatogonial Stem Cell Lines Using TALEN and Double-Nicking CRISPR/Cas9

Mouse spermatogonial stem cells (SSCs) can be cultured for multiplication and maintained for long periods while preserving their spermatogenic ability. Although the cultured SSCs, named germline stem (GS) cells, are targets of genome modification, this process remains technically difficult. In the present study, we tested TALEN and double-nicking CRISPR/Cas9 on GS cells, targeting Rosa26 and Stra8 loci as representative genes dispensable and indispensable in spermatogenesis, respectively. Harvested GS cell colonies showed a high targeting efficiency with both TALEN and CRISPR/Cas9. The Rosa26-targeted GS cells differentiated into fertility-competent sperm following transplantation. On the other hand, Stra8-targeted GS cells showed defective spermatogenesis following transplantation, confirming its prime role in the initiation of meiosis. TALEN and CRISPR/Cas9, when applied in GS cells, will be valuable tools in the study of spermatogenesis and for revealing the genetic mechanism of spermatogenic failure

Stereomicroscopic view of cultured adult mouse testis tissues.

<p>(A) Six-week-old <i>Acr</i>-GFP mouse testis tissue fragments on culture days 0, 3, and 10. Upper row is GFP excitation view and lower row is bright view. (B) Six-week-old <i>Acr</i>-GFP mouse testis tissue fragments on culture days 0, 15, and 82. Weak GFP expression was maintained. (C-E) Immunohistochemistry of cultured tissues with antibodies to BrdU and GFP, counterstained with Hoechst. Testis tissue fragments of 6-week-old <i>Acr</i>-GFP (C and D) and 24-week-old <i>Gsg2</i>-GFP (E) mice were cultured, and then analyzed on days 42 (<b>C</b>), 85 (<b>D</b>), and 48 (<b>E</b>), respectively. The dashed rectangular area in the left picture of C is enlarged on the right. Arrows indicate BrdU-positive round spermatids in C and elongating spermatids in E. Scale bars, 1 mm (A, B); 10 μm (C, E); 50 μm (D).</p

Extent of GFP expression in adult and pup testis tissues.

<p>(A) GFP expression images of testis tissues, from 2.5 dppp and seven-week-old Acr-GFP mice, cultured for 5 weeks. (B) PAS staining images of testis tissues, from 2.5 dppp and seven-week-old <i>Acr-</i>GFP mice, cultured for 5 weeks. The dotted rectangular areas are enlarged on the right. (C) Adults and pups were compared on the basis of the extent of <i>Acr</i>-GFP expression scored (judged at culture week 5). Testis tissue fragments of <i>Acr</i>-GFP mice, 2.5–4.5 dpp and 7–8 weeks old, were cultured for five weeks. Adult and pup testis tissues were examined in a total of 34 and 39 tissue pieces in three culture experiments, respectively (means±s.d., P<0.025 (Student’s t-test)). (D) The frequency of seminiferous tubules containing differentiated germ cells. Adult and pup testis tissues were examined in a total of 32 and 36 tissue pieces in three culture experiments, respectively. Sections stained with periodic acid Schiff were examined and the number of seminiferous tubules containing differentiated germ cells (spermatocytes, round spermatids, and/or elongating spermatids) asa well as seminiferous tubules not containing them were counted in each tissue to calculate the percentage of spermatogenesis-positive seminiferous tubule (means±s.d., P<0.002 (Student’s t-test)). Scale bars, 1 mm (A); 100 μm (B).</p

Summary of adult <i>Sl/Sl</i>^<i>d</i> mouse experiment, chronologically arranged.

<p>Summary of adult <i>Sl/Sl</i>^<i>d</i> mouse experiment, chronologically arranged.</p

Summary of adult <i>Sl/Sl</i>^<i>d</i> mouse experiment.

<p>Summary of adult <i>Sl/Sl</i>^<i>d</i> mouse experiment.</p

VAD experiment.

<p>(A) Testes of VAD treated <i>Gsg2</i>-GFP mice at, 5, 9 and 13 weeks old, showing decreasing GFP expression. Histology shows a corresponding extent of spermatogenesis on HE staining. At 13 weeks old, the GFP had completely disappeared and differentiating germ cells were totally removed. (B) Testis tissues of a VAD-treated <i>Acr</i>-GFP mouse, 24 weeks old, upper two images, and a VAD-treated <i>Gsg2</i>-GFP mouse, 13 weeks old, lower two images, regained GFP expression during culturing. Images were obtained on culture days 23 (upper two) and 70 (left two), respectively. (C) Immunohistochemistry of cultured testis tissue, on culture day 45, derived from a VAD-treated <i>Acr</i>-GFP 23-week-old mouse. Antibodies used were against GFP and PNA. Counterstaining with Hoechst was applied. The rectangular area in the left upper image is enlarged in the right upper. GFP (green) and PNA (red) channels are independently shown in the lower images. (D) Haploid cells were observed in the dissociated sample of cultured testis tissues from the VAD-treated <i>Gsg2</i>-GFP mouse, 13 weeks old, on culture day 73. Dissociated cells were stained with antibodies against GFP (green) and SP56 (red), a sperm-specific protein that localizes to the sperm surface and in the acrosomal matrix. Nuclei were stained with Hoechst. (E) A sperm was found in a dissociated sample of cultured tissue from a VAD-treated <i>Acr</i>-GFP mouse, 23 weeks old, on culture day 50. It was stained with anti-GFP antibody along with nuclear staining by Hoechst. Scale bars, 1 mm (B); 50 μm (A, C); 10 μm (D, E).</p

Summary of VAD experiment.

<p>Summary of VAD experiment.</p