ADHD患児とその保護者の服薬アドヒアランス調査

【目的】注意欠如・多動症（ADHD）の患児とその保護者が薬物治療をどのように評価し，治療に向き合っているのかを明らかにする。【方法】ADHDの診断を受け，メチルフェニデート徐放剤およびアトモキセチンを処方された小１から高３までの患児94 人と保護者106人に質問紙調査と半構造化面接を行った。【結果】90％以上で服薬は規則正しく行われており，薬物治療に対する肯定的な評価は，患児・保護者で約80 ～ 90％と高かった。一方で，全面的に賛成しているわけではなく，約80％の保護者が否定的な意見も持っていた．否定的評価をする要因は，保護者は副作用を含めた長期的な影響への不安，患児は服薬の煩わしさや胃腸症状が多かった。定期的な薬物治療を続けているにも関わらず，効果と不安等を天秤にかけて治療を継続することへの積極的な支持は，患児・保護者で約50 ～ 60％であった。【結論】小児では，低年齢のため客観的に自身の状況を判断し，見通しをもって治療に参加することが難しい場合がある。患児へは胃腸症状への対処を，保護者へは治療の見通しや副作用について丁寧な説明を繰り返すことによって，薬物治療への否定的評価が軽減され，服薬アドヒアランスが向上する可能性がある

Atomic structures and functional implications of the archaeal RecQ-like helicase Hjm

<p>Abstract</p> <p>Background</p> <p><it>Pyrococcus furiosus </it>Hjm (<it>Pfu</it>Hjm) is a structure-specific DNA helicase that was originally identified by <it>in vitro </it>screening for Holliday junction migration activity. It belongs to helicase superfamily 2, and shares homology with the human DNA polymerase Θ (PolΘ), HEL308, and <it>Drosophila </it>Mus308 proteins, which are involved in DNA repair. Previous biochemical and genetic analyses revealed that <it>Pfu</it>Hjm preferentially binds to fork-related Y-structured DNAs and unwinds their double-stranded regions, suggesting that this helicase is a functional counterpart of the bacterial RecQ helicase, which is essential for genome maintenance. Elucidation of the DNA unwinding and translocation mechanisms by <it>Pfu</it>Hjm will require its three-dimensional structure at atomic resolution.</p> <p>Results</p> <p>We determined the crystal structures of <it>Pfu</it>Hjm, in two apo-states and two nucleotide bound forms, at resolutions of 2.0–2.7 Å. The overall structures and the local conformations around the nucleotide binding sites are almost the same, including the side-chain conformations, irrespective of the nucleotide-binding states. The architecture of Hjm was similar to that of <it>Archaeoglobus fulgidus </it>Hel308 complexed with DNA. An Hjm-DNA complex model, constructed by fitting the five domains of Hjm onto the corresponding Hel308 domains, indicated that the interaction of Hjm with DNA is similar to that of Hel308. Notably, sulphate ions bound to Hjm lie on the putative DNA binding surfaces. Electron microscopic analysis of an Hjm-DNA complex revealed substantial flexibility of the double stranded region of DNA, presumably due to particularly weak protein-DNA interactions. Our present structures allowed reasonable homology model building of the helicase region of human PolΘ, indicating the strong conformational conservation between archaea and eukarya.</p> <p>Conclusion</p> <p>The detailed comparison between our DNA-free <it>Pfu</it>Hjm structure and the structure of Hel308 complexed with DNA suggests similar DNA unwinding and translocation mechanisms, which could be generalized to all of the members in the same family. Structural comparison also implied a minor rearrangement of the five domains during DNA unwinding reaction. The unexpected small contact between the DNA duplex region and the enzyme appears to be advantageous for processive helicase activity.</p

Cyclophosphamide Promotes Arrested Development of the Dental Root in Mice

Cyclophosphamide (CPA) is a commonly used chemotherapeutic agent to treat cancer. Among its many side effects is the well-known consequence on tooth development when administered at early ages. This study elucidated the effects of CPA on development of the mandibular molar in mice. Mice received a single intraperitoneal injection of CPA at different doses and development times. CPA treatment led to weight loss and alopecia but had no effect on disturbances in tooth eruption or crown shape. However, at higher doses, there was arrested root development and early apical foramen closure histologically related to the formation of the cervical loop structure in the apical portion of the root. In cell culture experiments, the Hertwig\u27s epithelial root sheath cell line (HERS01a) was cultured with or without CPA. At high doses of CPA, HERS01a cells showed decreases in E-cadherin expression, while N-cadherin expression was upregulated, indicating that this cadherin switch may promote an epithelial-to-mesenchymal transition (EMT)-like phenomenon. These findings suggest that administration of high doses of CPA can lead to arrested root development of the molars and an EMT-like phenomenon.福岡歯科大学2019年

Fibrillin-1 and fibrillin-2 are essential for formation of thick oxytalan fibers in human nonpigmented ciliary epithelial cells in vitro.

The ciliary zonule, also known as Zinn\u27s zonule, is composed of oxytalan fibers. However, the mechanism by which epithelial cells in the ciliary body form these fibers in not fully understood. We examined human nonpigmented ciliary epithelial cells to determine the appearance and amount of oxytalan fibers in terms of positivity for their major components, fibrillin-1 and fibrillin-2. Examination of fibrillin-1 and fibrillin-2 expression by immunofluorescence revealed that thin fibers positive for fibrillin-1 on Day 2 changed to thick fibers by Day 8. The fibers positive for fibrillin-2 appeared on the thick fibrillin-1-positive fibers after Day 4. Northern blot analysis revealed that the level of fibrillin-1 did not change markedly, while induction of fibrillin-2 gene was evident on Day 5. Western blot analysis showed that fibrillin-1 deposition increased gradually, while that of fibrillin-2 increased markedly from Day 5 to Day 8. Fibrillin-1 suppression did not lead to the formation of fibrillin-2-positive thick fibers, whereas fibrillin-2 suppression led to the formation of fibrillin-1-positive thin fibers, but not thick fibers. These results suggest that both fibrillin-1 and fibrillin-2 are essential for the formation of thick oxytalan fibers in the ciliary zonule and are informative for clarifying the mechanism of homeostasis of the ocular matrix.福岡歯科大学2013年

TGF-β mediated FGF10 signaling in cranial neural crest cells controls development of myogenic progenitor cells through tissue–tissue interactions during tongue morphogenesis

AbstractSkeletal muscles are formed from two cell lineages, myogenic and fibroblastic. Mesoderm-derived myogenic progenitors form muscle cells whereas fibroblastic cells give rise to the supportive connective tissue of skeletal muscles, such as the tendons and perimysium. It remains unknown how myogenic and fibroblastic cell–cell interactions affect cell fate determination and the organization of skeletal muscle. In the present study, we investigated the functional significance of cell–cell interactions in regulating skeletal muscle development. Our study shows that cranial neural crest (CNC) cells give rise to the fibroblastic cells of the tongue skeletal muscle in mice. Loss of Tgfbr2 in CNC cells (Wnt1-Cre;Tgfbr2flox/flox) results in microglossia with reduced Scleraxis and Fgf10 expression as well as decreased myogenic cell proliferation, reduced cell number and disorganized tongue muscles. Furthermore, TGF-β2 beads induced the expression of Scleraxis in tongue explant cultures. The addition of FGF10 rescued the muscle cell number in Wnt1-Cre;Tgfbr2flox/flox mice. Thus, TGF-β induced FGF10 signaling has a critical function in regulating tissue–tissue interaction during tongue skeletal muscle development

Epimorphin Mediates Mammary Luminal Morphogenesis through Control of C/EBPβ

We have shown previously that epimorphin (EPM), a protein expressed on the surface of myoepithelial and fibroblast cells of the mammary gland, acts as a multifunctional morphogen of mammary epithelial cells. Here, we present the molecular mechanism by which EPM mediates luminal morphogenesis. Treatment of cells with EPM to induce lumen formation greatly increases the overall expression of transcription factor CCAAT/enhancer binding protein (C/EBP)β and alters the relative expression of its two principal isoforms, LIP and LAP. These alterations were shown to be essential for the morphogenetic activities, since constitutive expression of LIP was sufficient to produce lumen formation, whereas constitutive expression of LAP blocked EPM-mediated luminal morphogenesis. Furthermore, in a transgenic mouse model in which EPM expression was expressed in an apolar fashion on the surface of mammary epithelial cells, we found increased expression of C/EBPβ, increased relative expression of LIP to LAP, and enlarged ductal lumina. Together, our studies demonstrate a role for EPM in luminal morphogenesis through control of C/EBPβ expression

MLH1-mediated recruitment of FAN1 to chromatin for the induction of apoptosis triggered by O6-methylguanine

O6 -Methylguanines (O6 -meG), which are produced in DNA by the action of alkylating agents, are mutagenic and cytotoxic, and induce apoptosis in a mismatch repair (MMR) protein-dependent manner. To understand the molecular mechanism of O6 -meG-induced apoptosis, we performed functional analyses of FANCD2 and FANCI-associated nuclease 1 (FAN1), which was identified as an interacting partner of MLH1. Immunoprecipitation analyses showed that FAN1 interacted with both MLH1 and MSH2 after treatment with N-methyl-N-nitrosourea (MNU), indicating the formation of a FAN1-MMR complex. In comparison with control cells, FAN1-knockdown cells were more resistant to MNU, and the appearances of a sub-G1 population and caspase-9 activation were suppressed. FAN1 formed nuclear foci in an MLH1-dependent manner after MNU treatment, and some were colocalized with both MLH1 foci and single-stranded DNA (ssDNA) created at damaged sites. Under the same condition, FANCD2 also formed nuclear foci, although it was dispensable for the formation of FAN1 foci and ssDNA. MNU-induced formation of ssDNA was dramatically suppressed in FAN1-knockdown cells. We therefore propose that FAN1 is loaded on chromatin through the interaction with MLH1 and produces ssDNA by its exonuclease activity, which contributes to the activation of the DNA damage response followed by the induction of apoptosis triggered by O6 -meG.福岡歯科大

Paediatric HIV and elimination of mother-to-child transmission of HIV in the ASEAN region: a call to action

Recent achievements in scaling up paediatric antiretroviral therapy (ART) have changed the life of children living with HIV, who now stay healthy and live longer lives. However, as it becomes more of a chronic infection, a range of new problems have begun to arise. These include the disclosure of HIV serostatus to children, adherence to ART, long-term toxicities of antiretroviral drugs and their sexual and reproductive health, which are posing significant challenges to the existing health systems caring for children with HIV with limited resources, experiences and capacities. While intensified efforts and actions to improve care and treatment for these children are needed, it is crucial to accelerate the prevention of mother-to-child transmission (PMTCT) of HIV, which is the main cause of paediatric HIV in the ASEAN region so as to eliminate the fundamental cause of the problem. This report argues that given over 70% of women have access to at least one antenatal care visit in the region and acceptance of HIV testing after receiving counselling on PMTCT could be as high as 90%, there is an opportunity to strengthen PMTCT services and eventually eliminate new paediatric HIV infections in the ASEAN countries