Pressure Study of BiS2-Based Superconductors Bi4O4S3 and La(O,F)BiS2

We report the electrical resistivity measurements under pressure for the recently discovered BiS2-based layered superconductors Bi4O4S3 and La(O,F)BiS2. In Bi4O4S3, the transition temperature Tc decreases monotonically without a distinct change in the metallic behavior in the normal state. In La(O,F)BiS2, on the other hand, Tc initially increases with increasing pressure and then decreases above ? 1 GPa. The semiconducting behavior in the normal state is suppressed markedly and monotonically, whereas the evolution of Tc is nonlinear. The strong suppression of the semiconducting behavior without doping in La(O,F)BiS2 suggests that the Fermi surface is located in the vicinity of some instability. In the present study, we elucidate that the superconductivity in the BiS2 layer favors the Fermi surface at the boundary between the semiconducting and metallic behaviors.Comment: 4 pages, 6 figures, Accepted for publication in J. Phys. Soc. Jp

Chondrocyte Migration Mediated by Smad3/S1P3

Temporomandibular joint osteoarthritis is a degenerative disease that is characterized by permanent cartilage destruction. Transforming growth factor (TGF)-β is one of the most abundant cytokines in the bone matrix and is shown to regulate the migration of osteoprogenitor cells. It is hypothesized that TGF-β/Smad3 signaling affects cartilage homeostasis by influencing sphingosine 1-phosphate (S1P)/ S1P receptor signaling and chondrocyte migration. We therefore investigated the molecular mechanisms by which crosstalk may occur between TGF-β/Smad3 and S1P/S1P receptor signaling to maintain condylar cartilage and to prevent temporomandibular joint osteoarthritis. Abnormalities in the condylar subchondral bone, including dynamic changes in bone mineral density and microstructure, were observed in Smad3-/- mice by microcomputed tomography. Cell-free regions and proteoglycan loss characterized the cartilage degradation present, and increased numbers of apoptotic chondrocytes and matrix metalloproteinase 13+ chondrocytes were also detected. Furthermore, expression of S1P receptor 3 (S1P3), but not S1P1 or S1P2, was significantly down-regulated in the condylar cartilage of Smad3-/- mice. By using RNA interference technology and pharmacologic tools, S1P was found to transactivate Smad3 in an S1P3/TGF-β type II receptor-dependent manner, and S1P3 was found to be required for TGF-β-induced migration of chondrocyte cells and downstream signal transduction via Rac1, RhoA, and Cdc42. Taken together, these results indicate that the Smad3/S1P3 signaling pathway plays an important role in the pathogenesis of temporomandibular joint osteoarthritis

Skeletal open bite with amelogenesis imperfecta treated with compression osteogenesis : a case report

Background: We successfully treated a 37-year-old male who had skeletal open bite with severe amelogenesis imperfecta (AI) with orthodontics, compression osteogenesis, and prosthodontics. Case presentation: The patient was diagnosed with severe anterior open bite caused by severe AI. Corticotomy was performed on both buccal and palatal sides of the molar regions, and anchor plates were placed onto the bilateral zygomatic buttress and the center of the hard palate. After corticotomy, posterior maxillary segments were moved 3.5 mm superiorly to correct skeletal open bite with elastic chains. After 8-month, overbite had decreased by 2.0 mm. After further 5 months of prosthodontic preparation, orthodontic appliances were removed, and provisional crowns were set on all teeth. The anterior open bite was corrected, and ideal occlusion with a Class I molar relationship was achieved. The upper first molars were intruded 3.5 mm, resulting in 3.0o counter-clockwise rotation of the mandible. The total active treatment period was 16 months. Acceptable occlusion with a good facial profile was well maintained throughout the 8-year retention period. Conclusions: Our results indicate long-term stability after interdisciplinary treatment combining orthodontics, oral surgery, and prosthodontics in a patient with severe anterior open bite and AI

Asymmetric Synthesis of N-Fmoc-(S)-7-aza-tryptophan via Alkylation of Chiral Nucleophilic Glycine Equivalent

Ni(II)-complexes, derived from glycine Schiff bases with chiral tridentate ligands, have been used as powerful tools for the synthesis of structurally diverse tailor-made amino acids. In this manuscript, asymmetric alkylation reaction between chiral nucleophilic glycine derived Ni-complex and 3-(chloromethyl)-1H-pyrrolo[2,3-b]pyridine has been developed under convenient conditions, which affords the corresponding alkylated Ni-complex in 74 % yield and excellent diastereoselectivity (only one isomer). This reaction features convenient conditions and completely controlled diastereoselectivity, which provides a highly valuable approach for asymmetric synthesis of 7-aza-tryptophan

Asymmetric Synthesis of Tailor-Made Amino Acids Using Chiral Ni(II) Complexes of Schiff Bases. An Update of the Recent Literature

Tailor-made amino acids are indispensable structural components of modern medicinal chemistry and drug design. Consequently, stereo-controlled preparation of amino acids is the area of high research activity. Over last decade, application of Ni(II) complexes of Schiff bases derived from glycine and chiral tridentate ligands has emerged as a leading methodology for the synthesis of various structural types of amino acids. This review article summarizes examples of asymmetric synthesis of tailor-made α-amino acids via the corresponding Ni(II) complexes, reported in the literature over the last four years. A general overview of this methodology is provided, with the emphasis given to practicality, scalability, cost-structure and recyclability of the chiral tridentate ligands.This research was funded by the National Natural Science Foundation of China (No. 21761132021), and IKERBASQUE, Basque Foundation for Science

Next generation organofluorine containing blockbuster drugs

Funding: the National Natural Science Foundation of China (No. 21761132021), the Hungarian Research Foundation (NKFIH No. K 119282), and Ministry of Human Capacities, Hungary grant 20391-3/2018/FEKUSTRAT. The Qinlan Project of Jiangsu Province, and IKERBASQUE, the Basque Foundation for Science are also acknowledged.The role of organo-fluorine compounds in modern health, food and energy related industries is widely-appreciated. The unique properties that fluorine imparts to organic molecules, stemming from its high electronegativity and stability when bound to carbon, finds it increasing being used in the development of new bioactivities. Around 25% of the current blockbuster drugs contain fluorine and this number is increasing to well above 30% for recent FDA approvals. In this Review we highlight a selection of the most successful organo-fluorine drugs, that have achieved blockbuster status, namely, sitagliptin (diabetes), sofosbuvir (hepatitis C), emtricitabine (HIV), glecaprevir/pibrentasvir (hepatitis C), elvitegravir (HIV), dolutegravir (HIV), bictegravir (HIV), efavirenz (HIV), enzalutamide (prostate cancer), aubagio (immunomodulatory) and paliperidone palmitate (schizophrenia). For each compound we discuss their discovery, their relevant disease state and how they are made, emphasizing the source of fluorine-containing moieties, and where known, their mode of action.PostprintPeer reviewe