Isolation and Structural Determination of the First 8-epi-type Tetrodotoxin Analogs from the Newt, Cynops ensicauda popei, and Comparison of Tetrodotoxin Analogs Profiles of This Newt and the Puffer Fish, Fugu poecilonotus

Identification of new tetrodotoxin (TTX) analogs from TTX-possessing animals might provide insight into its biosynthesis and metabolism. In this study, four new analogs, 8-epi-5,6,11-trideoxyTTX, 4,9-anhydro-8-epi-5,6,11-trideoxyTTX, 1-hydroxy-8-epi-5,6,11-trideoxyTTX, and 1-hydroxy-4,4a-anhydro-8-epi-5,6,11-trideoxyTTX, were isolated from the newt, Cynops ensicauda popei, and their structures were determined using spectroscopic methods. These are the first 8-epi-type analogs of TTX that have been found in a natural source. Furthermore, we examined the composition of the TTX analogs in this newt and in the ovary of the puffer fish, Fugu poecilonotus, using LC/MS. The results indicate that TTX and 11-deoxyTTX were present in both sources. However, 6-epiTTX and 8-epi-type analogs were detected only in the newt, while 5,6,11-trideoxyTTX was a specific and major analog in the puffer fish. Such considerable differences among analog compositions might reflect differences in the biosynthesis or metabolism of TTX between these animals

Epoxide-Opening Cascades in the Synthesis of Polycyclic Polyether Natural Products

The structural features of polycyclic polyether natural products can, in some cases, be traced to their biosynthetic origin. However in case that are less well understood, only biosynthetic pathways that feature dramatic, yet speculative, epoxide-opening cascades are proposed. We summarize how such epoxide-opening cascade reactions have been used in the synthesis of polycyclic polyethers (see scheme) and related natural products. The group of polycyclic polyether natural products is of special interest owing to the fascinating structure and biological effects displayed by its members. The latter includes potentially therapeutic antibiotic, antifungal, and anticancer properties, and extreme lethality. The polycyclic structural features of this class of compounds can, in some cases, be traced to their biosynthetic origin, but in others that are less well understood, only to proposed biosynthetic pathways that feature dramatic, yet speculative, epoxide-opening cascades. In this review we summarize how such epoxide-opening cascade reactions have been used in the synthesis of polycyclic polyethers and related natural products

複数の埋伏過剰歯を伴った石灰化嚢胞性歯原性腫瘍の1例

石灰化嚢胞性歯原性腫瘍(以下CCOT)は病理組織学的に,裏装上皮内にghost cellの出現とそれらの石灰化を特徴とし,また,歯牙腫をはじめとする歯原性腫瘍を合併することがある.さらに,CCOT症例の半数前後は埋伏歯を伴うことが知られているが,複数の埋伏過剰歯を伴うことは稀である。今回われわれは,歯牙腫と8本の埋伏過剰歯を伴ったCCOTの1例を経験したので,その概要を報告する.症例は40歳代の男性で,近歯科医院を受診した際にX線検査にて右側上顎洞部に嚢胞様透過像が認められ,精査・加療目的に当科紹介となった.初診時,上顎右側側切歯から右側第一大臼歯部の頬側歯肉に弾性軟の腫脹を認め,波動が触知された.CTにて,右側上顎洞および鼻腔の下部に境界明瞭で単胞性の嚢胞様病変を認め,病変内部に大小の石灰化像および歯牙様石灰化像を認めた.全身麻酔下にて摘出術および対孔形成術を施行した.摘出組織ではCCOTとともに歯牙腫ならびに8本の埋伏歯を認めた.病理組織学的に上皮層内にghost cellとその石灰化がみられた.文献的に本症例のように複数の埋伏過剰歯を伴ったCCOTはきわめてまれであった.It is well known that an associated impacted tooth is seen in about half of cases with calcifying cystic odontogenic tumor (CCOT), but CCOT with two or more impacted teeth is extremely rare. This paper reports a case of CCOT with 8 impacted, supernumerary teeth. The patient is an adult male with swelling of right maxilla. X-ray examination showed a cystic lesion with calcification and with numerous impacted, supernumerary teeth. A clinical diagnosis of CCOT with odontoma was made. And surgical excised of the lesion was performed. Macroscopically, surgically excised specimen showed eight supernumerary teeth with formal and/or unformal shape were involved in the lesion, but these teeth were not enclosed by fibrous capsule. The lesion was diagnosed finally as CCOT with odontoma and with eight impacted, supernumerary teeth by pathological examination. The review of the literature yielded CCOT with more than 3 associated supernumerary has not been documental

Landscape Print

Print, morning glory and thistle landscape, dark colors, in gold framehttps://scholarworks.umt.edu/mansfieldartifacts/1457/thumbnail.jp