DKK1 Mediated Inhibition of Wnt Signaling in Postnatal Mice Leads to Loss of TEC Progenitors and Thymic Degeneration

Thymic epithelial cell (TEC) microenvironments are essential for the recruitment of T cell precursors from the bone marrow, as well as the subsequent expansion and selection of thymocytes resulting in a mature self-tolerant T cell repertoire. The molecular mechanisms, which control both the initial development and subsequent maintenance of these critical microenvironments, are poorly defined. Wnt signaling has been shown to be important to the development of several epithelial tissues and organs. Regulation of Wnt signaling has also been shown to impact both early thymocyte and thymic epithelial development. However, early blocks in thymic organogenesis or death of the mice have prevented analysis of a role of canonical Wnt signaling in the maintenance of TECs in the postnatal thymus.Here we demonstrate that tetracycline-regulated expression of the canonical Wnt inhibitor DKK1 in TECs localized in both the cortex and medulla of adult mice, results in rapid thymic degeneration characterized by a loss of DeltaNP63(+) Foxn1(+) and Aire(+) TECs, loss of K5K8DP TECs thought to represent or contain an immature TEC progenitor, decreased TEC proliferation and the development of cystic structures, similar to an aged thymus. Removal of DKK1 from DKK1-involuted mice results in full recovery, suggesting that canonical Wnt signaling is required for the differentiation or proliferation of TEC populations needed for maintenance of properly organized adult thymic epithelial microenvironments.Taken together, the results of this study demonstrate that canonical Wnt signaling within TECs is required for the maintenance of epithelial microenvironments in the postnatal thymus, possibly through effects on TEC progenitor/stem cell populations. Downstream targets of Wnt signaling, which are responsible for maintenance of these TEC progenitors may provide useful targets for therapies aimed at counteracting age associated thymic involution or the premature thymic degeneration associated with cancer therapy and bone marrow transplants

The Wnt Signaling Antagonist Kremen1 is Required for Development of Thymic Architecture

Wnt signaling has been reported to regulate thymocyte proliferation and selection at several stages during T cell ontogeny, as well as the expression of FoxN1 in thymic epithelial cells (TECs). Kremen1 (Krm1) is a negative regulator of the canonical Wnt signaling pathway, and functions together with the secreted Wnt inhibitor Dickkopf (Dkk) by competing for the lipoprotein receptor-related protein (LRP)-6 co-receptor for Wnts. Here krm1 knockout mice were used to examine krm1 expression in the thymus and its function in thymocyte and TEC development. krm1 expression was detected in both cortical and medullary TEC subsets, as well as in immature thymocyte subsets, beginning at the CD25+CD44+ (DN2) stage and continuing until the CD4+CD8+(DP) stage. Neonatal mice show elevated expression of krm1 in all TEC subsets. krm1− / − mice exhibit a severe defect in thymic cortical architecture, including large epithelial free regions. Much of the epithelial component remains at an immature Keratin 5+ (K5) Keratin 8+(K8) stage, with a loss of defined cortical and medullary regions. A TOPFlash assay revealed a 2-fold increase in canonical Wnt signaling in TEC lines derived from krm1− / − mice, when compared with krm1+ / + derived TEC lines. Fluorescence activated cell sorting (FACS) analysis of dissociated thymus revealed a reduced frequency of both cortical (BP1+EpCAM+) and medullary (UEA-1+ EpCAMhi) epithelial subsets, within the krm1− / − thymus. Surprisingly, no change in thymus size, total thymocyte number or the frequency of thymocyte subsets was detected in krm1− / − mice. However, our data suggest that a loss of Krm1 leads to a severe defect in thymic architecture. Taken together, this study revealed a new role for Krm1 in proper development of thymic epithelium

Fetal Goitrous Hypothyroidism due to Maternal Thyroid Stimulation-Blocking Antibody: A Case Report

Most fetal goitrous hypothyroidisms are reportedly caused by the maternal use of an antithyroid drug or fetal dyshormonogenesis. However, fetal goitrous hypothyroidism due to the transplacental passage of maternal thyroid stimulation-blocking antibody (TSBAb) is extremely rare. A woman at 28 weeks of gestation was found to have a fetal goiter by ultrasonography. Because the maternal serum showed hypothyroidism with an elevated titer of TSBAb, levothyroxine sodium was administered. The patient delivered a male infant, 3,412 g, with a goiter at term. Umbilical blood revealed primary hypothyroidism with increased TSBAb, and the infant was given levothyroxine sodium. After a month, neonatal thyroid function and TSBAb levels became normal. Attention should be paid to possible fetal hypothyroidism when a fetal goiter is observed to avoid impaired mental development of the neonate.ArticleFETAL DIAGNOSIS AND THERAPY. 28(4):220-224 (2010)journal articl

Label Retention Identifies a Multipotent Mesenchymal Stem Cell-Like Population in the Postnatal Thymus

Thymic microenvironments are essential for the proper development and selection of T cells critical for a functional and self-tolerant adaptive immune response. While significant turnover occurs, it is unclear whether populations of adult stem cells contribute to the maintenance of postnatal thymic epithelial microenvironments. Here, the slow cycling characteristic of stem cells and their property of label-retention were used to identify a K5-expressing thymic stromal cell population capable of generating clonal cell lines that retain the capacity to differentiate into a number of mesenchymal lineages including adipocytes, chondrocytes and osteoblasts suggesting a mesenchymal stem cell-like phenotype. Using cell surface analysis both culture expanded LRCs and clonal thymic mesenchymal cell lines were found to express Sca1, PDGFRα, PDGFRβ,CD29, CD44, CD49F, and CD90 similar to MSCs. Sorted GFP-expressing stroma, that give rise to TMSC lines, contribute to thymic architecture when reaggregated with fetal stroma and transplanted under the kidney capsule of nude mice. Together these results show that the postnatal thymus contains a population of mesenchymal stem cells that can be maintained in culture and suggests they may contribute to the maintenance of functional thymic microenvironments

Fetal Goitrous Hypothyroidism due to Maternal Thyroid Stimulation-Blocking Antibody: A Case Report

Most fetal goitrous hypothyroidisms are reportedly caused by the maternal use of an antithyroid drug or fetal dyshormonogenesis. However, fetal goitrous hypothyroidism due to the transplacental passage of maternal thyroid stimulation-blocking antibody (TSBAb) is extremely rare. A woman at 28 weeks of gestation was found to have a fetal goiter by ultrasonography. Because the maternal serum showed hypothyroidism with an elevated titer of TSBAb, levothyroxine sodium was administered. The patient delivered a male infant, 3,412 g, with a goiter at term. Umbilical blood revealed primary hypothyroidism with increased TSBAb, and the infant was given levothyroxine sodium. After a month, neonatal thyroid function and TSBAb levels became normal. Attention should be paid to possible fetal hypothyroidism when a fetal goiter is observed to avoid impaired mental development of the neonate.ArticleFETAL DIAGNOSIS AND THERAPY. 28(4):220-224 (2010)journal articl

Aspects of Midwifery Care Valued by Independent Midwives

目的：開業助産師に妊産褥婦への「関わり」を語ってもらう中で、その思考・判断・実践を明らかにすることである。方法：研究対象者は、研究協力に同意を得られた開業助産師８名で、半構造化インタビューを行い語られた内容から逐語録を作成し、質的に内容を分析した。研究期間は、2020 年９月～2023 年２月である。結果：開業助産師の語りを分析した結果、23 コードから 10 サブカテゴリーと３カテゴリーを生成した。３カテゴリーは、【助産師職にこだわる】【開業助産師としての日常と助産ケア】【未来へ向かう助産ケア】であった。考察：開業助産師は、継続的に寄り添うケアを基本とし、これは少しの異常を見逃さないことに繋がることと考える。さらに、ケアの対象は地域への母子を含めた広がりを示唆していると考える。結論：今回、開業助産師の思考・判断・実践内容を教授することは、助産師学生への助産ケアへの教育に貢献できると考える。Purpose：This study was to determine the thoughts, judgments, and practices of independent midwives when asked to “relate” to pregnant women, postpartum women, and postpartum mothers. Methods：The study subjects were eight practicing midwives who agreed to cooperate in the study. Semi-structured interviews were conducted, verbatim transcripts were made from their statements, and their contents were analyzed qualitatively. The study period was from September 2020 to February 2023. Results: After analyzing the narratives of practicing midwives, 10 subcategories and 3 categories were generated from 23 codes, and the 3 categories were [Focusing on the midwifery profession], [Daily life and midwifery care as a practicing midwife], and [Midwifery care for the future]. Discussion: It is believed that practicing midwives realize that the basis of care is to be continuously close to women, and that this leads to not overlooking even the slightest abnormality. Furthermore, we believe that this suggests that the scope of care is expanding to include mothers and children in the community. We believe that teaching the thinking, judgment, and practice of independent midwives can contribute to the education of midwifery care for midwifery students.departmental bulletin pape

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives