Optimal indication of adding pancreatic juice cytology in the diagnosis of malignant intraductal papillary mucinous neoplasm of the pancreas.

Background/objectives: Positive pancreatic juice cytology (PJC) is an important finding when considering surgical resection in patients with intraductal papillary mucinous neoplasm (IPMN); however, guidelines do not recommend endoscopic retrograde cholangiopancreatography (ERCP) for PJC. This study aimed to clarify the findings worthy of adding PJC for diagnosing high-grade dysplasia (HGD) and invasive carcinoma (IC) in patients with IPMN.

Methods: Patients with IPMN who underwent preoperative PJC and surgical resection at Hiroshima University Hospital were enrolled, and the diagnostic yield of malignant IPMN based on PJC and clinical and imaging findings and the incidence of post-ERCP pancreatitis (PEP) were retrospectively analyzed.

Synthesis of ()-Enediynes via Stereoinvertive Nucleophilic Substitution of ()-Sulfonylethenes with Arylethynide, and Their Aggregation-Induced Optical Properties.

()-Enediynes were successfully synthesized from a trio of terminal ethynes through consecutive three-step reactions: iodosulfonylation of ethyne with I/PhSONa, followed by ethynylations of iodo and sulfonyl moieties of the resulting iodosulfonylethene via Sonogashira-Hagihara coupling and nucleophilic addition-elimination, respectively. The molecular structure of the obtained ()-enediyne was fully characterized by X-ray crystal structure analysis, revealing that the nucleophilic substitution of ()-sulfonylethene with arylethynide underwent a selective stereoinversion. The ()-enediynes exhibited photoluminescence in both the solution and solid states (crystals and powders).

Effectiveness and safety of a new clip for delivery using a duodenoscope for bleeding after endoscopic sphincterotomy.

Hemostasis for post-endoscopic sphincterotomy (post-EST) bleeding involves no standard strategy. New clips designed for delivery using the duodenoscope (SureClip, Micro-Tech, Nanjing, China) have been utilized for gastrointestinal bleeding hemostasis and bleeding prevention after polypectomy and papillectomy. We retrospectively analyzed the effectiveness and safety of SureClip for post-EST bleeding.

Chemodivergent Synthesis of Polycyclic Aromatic Diarylamines and Carbazoles by Thermal/Photochemical Process-Controlled Dephosphinylative Functionalizations of Amino(phosphinyl)arenes.

A chemodivergent synthesis of polycyclic aromatic diarylamines and carbazoles was established by employing thermally or photochemically controlled processes using KOBu/1,10-phenanthroline. The synthetic processes involved the dephosphinylation of 9-amino-10-(phosphinyl)phenanthrenes, which were obtained through a regioselective palladium-catalyzed direct [4 + 2] benzannulation of phosphinyl ynamines with 2-iodobiphenyls. When the dephosphinylation was conducted under heating conditions (∼100 °C), it proceeded to yield 9-aminophenanthrene.

Synthesis, optical properties and crystal structure of (,)-1,3-(3,4:9,10-dibenzododeca-1,11-diene-5,7-diyne-1,12-di-yl)benzene.

The de-hydro-benzannulene (,)-1,3-(3,4:9,10-dibenzododeca-1,11-diene-5,7-diyne-1,12-di-yl)benzene, CH, was successfully synthesized photocatalyst-assisted stereoselective reductive de-sulfonyl-ation of 1,3-bis-{1-phenyl-sulfonyl-2-[2-(tri-methyl-silylethyn-yl)phen-yl]ethen-yl}benzene, CHOSSi, and subsequent desilylative cyclization of the resulting (,)-bis-silyl-protected dienyne, CHSi. The structure of the de-hydro-benzannulene thus obtained was confirmed by single-crystal X-ray analysis; three benzene rings are connected to one another by a 1,3-butadiynylene and a pair of ethenylene arrays. Although the π-system expanded efficiently in the de-hydro-benzannulene, it was observed that the butadiynylene and ethenylene arrays were strained, showing smaller [171.

Process-Divergent Syntheses of 4- and 5-Sulfur-Functionalized 1,2,3-Triazoles via Copper-Catalyzed Azide-Alkyne Cycloadditions of 1-Phosphinyl-2-sulfanylethynes.

4-Sulfanyl-substituted 1,2,3-triazoles were provided regioselectively with good yields and broad scope via consecutive -BuOK-promoted dephosphinylation of 1-phosphinyl-2-sulfanylethynes and copper-catalyzed azide-alkyne cycloadditions (CuAAC) with alkyl azides. Unsymmetrically substituted ditriazoles were successfully obtained using a tandem dephosphinylative CuAAC protocol with diazides. Direct CuAAC of the 1-phosphinyl-2-sulfanylethynes with azides afforded regioisomeric mixtures of 4-phosphinyl-5-sulfanyl- and 5-phosphinyl-4-sulfanyl-1,2,3-triazoles that were easily separable from one another.

Curative surgery for primary squamous cell carcinoma of the liver: a rare case study.

Primary squamous cell carcinoma (SCC) of the liver is an extremely rare disease with a very poor prognosis. An 83-year-old woman was referred to our hospital with left abdominal pain. Laboratory data showed mildly elevated C-reactive protein and biliary enzymes.

Endoscopic approach in the diagnosis of high-grade pancreatic intraepithelial neoplasia.

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is essential for improving prognosis; however, diagnosing PDAC at an early stage is challenging. In patients with localized high-grade pancreatic intraepithelial neoplasia (HG-PanIN), whose tumorous lesion is undetectable on cross-sectional images such as computed tomography or magnetic resonance image, long-term survival is expected. Pancreatic cystic lesions or main pancreatic duct (MPD) dilatation are important indirect findings for the initial diagnosis of HG-PanIN.

Dephosphinylative [4 + 2] Benzannulation of Phosphinyl Ynamines: Application to the Modular Synthesis of Polycyclic Aromatic Amines.

A series of 9-amino-10-halophenanthrenes were synthesized through a one-pot process, including dephosphinylative Sonogashira-Hagihara coupling of 2-bromobiphenyls with air-stable phosphinyl ynamines, followed by halonium-promoted [4 + 2] benzannulation of the resulting 2-(aminoethynyl)biphenyls. Nonsubstituted and methyl-substituted 2-bromobiphenyls rapidly underwent the Sonogashira-Hagihara aminoethynylation and the halogenative Friedel-Crafts benzannulation to provide the corresponding amino(halo)phenanthrenes in high yields, while electron-sufficient and -deficient substrates did slowly undergo the former and the latter to result in low yields, respectively. This protocol worked well for the syntheses of highly π-extended aminophenanthrenes and aminobenzonaphthothiophenes with different optical properties.

Head-to-Tail Oligomerization by Silylene-Tethered Sonogashira Coupling on Ag(111).

On-surface synthesis is a powerful method for the fabrication of π-conjugated nanomaterials. Herein, we demonstrate chemoselective Sonogashira coupling between (trimethylsilyl)ethynyl and chlorophenyl groups in silylethynyl- and chloro-substituted partially fluorinated phenylene ethynylenes (SiCPFPEs) on Ag(111). The desilylative Sonogashira coupling occurred with high chemoselectivity up to 75 %, while the competing Ullmann and desilylative Glaser homocoupling reactions were suppressed.

Pathological Features and Imaging Findings in Pancreatic Carcinoma In Situ.

Objectives: This study aimed to evaluate the pathological features and imaging findings of pancreatic carcinoma in situ (PCIS).

Methods: Twenty patients with PCIS were categorized as flat (F) (n = 6) and low papillary (LP) (n = 14) types.

Results: None of F type and 8 (57%) of 14 with LP type lesions showed intraductal infiltrations of the main pancreatic duct (MPD) greater than 10 mm.

Process-Controlled Regiodivergent Copper-Catalyzed Azide-Alkyne Cycloadditions: Tailor-made Syntheses of 4- and 5-Bromotriazoles from Bromo(phosphoryl)ethyne.

We developed a regiodivergent syntheses of 4- and 5-bromo-substituted 1,2,3-triazoles in copper-catalyzed azide-alkyne cycloadditions (CuAACs) by taking advantage of bromo(phosphoryl)ethyne as a bromoethyne equivalent. A one-shot dephosphorylative CuAAC of afforded 4-bromotriazoles, which was transformed into a histone deacetylase 8 (HDAC8)-selective inhibitor, NCC-149. However, the direct CuAAC catalyzed by CuI/Cu(OAc) provided 5-bromo-4-phosphoryltriazoles.

Nickel-Catalyzed Decarbonylative Alkylation of Aroyl Fluorides Assisted by Lewis-Acidic Organoboranes.

Herein, nickel-catalyzed decarbonylative C-F bond alkylation of aroyl fluorides with organoboron reagents is reported. Aroyl fluorides are more chemically stable than the corresponding aroyl chlorides and can be readily synthesized from the corresponding carboxylic acids. The fluoronickel intermediate formed via oxidative addition interacts with Lewis-acidic trialkylboranes, and the subsequent decarbonylative alkylation proceeds.

Cobalt-Catalyzed Hydroacylative Dimerization of Allenes Leading to Skipped Dienes.

A cobalt-diphosphine catalyst has been found to promote a selective 1:2 coupling reaction between aldehydes and allenes to form β,δ-dialkylidene ketones, featuring skipped diene moieties, with high regioselectivities and stereoselectivities. The reaction is distinct from previously reported, rhodium-catalyzed aldehyde-allene 1:2 coupling to afford β,γ-dialkylidene ketones bearing 1,3-diene moieties. The present hydroacylative dimerization involves a unique allene/allene oxidative cyclization mode to form a C1-C2 linkage between the allene molecules.

Disproportionation-induced solid-state fluorescence in 6,13-dihydropentacenes.

The thermally and photolytically induced disproportionation of 6,13-dihydropentacene derivatives into tetrahydropentacenes and pentacenes results in unique solid-state fluorescence. The fluorescence thereby depends on the molecular structure and the molecular arrangement in the solid state.

A meso-meso β-β β-β Triply Linked Subporphyrin Dimer.

A meso-meso β-β β-β triply linked subporphyrin dimer 6 was synthesized by stepwise reductive elimination of β-to-β doubly Pt -bridged subporphyrin dimer 9. Dimer 6 was characterized by spectroscopic and electrochemical measurements, theoretical calculations, and picosecond time-resolved transient absorption spectroscopy. X-ray diffraction analysis reveals that 6 has a bowl-shaped structure with a positive Gaussian curvature.

A Directly Fused Subporphyrin Dimer with a Wavelike Structure.

[Ni(cod)2 ]-mediated intramolecular reductive coupling of β-β' linked meso,meso'-dibromosubporphyrin dimer gave the anti-isomer of meso-meso', β-β' doubly linked subporphyrin dimer as the first example of a fused subporphyrin dimer. The fused dimer 3anti displays an wavelike coplanar structure, a perturbed and red-shifted absorption spectrum, reversible redox behaviors with a decreased electrochemical HOMO-LUMO band gap, and a short S1 -state lifetime owing to the delocalized π-electronic network.

The molecular mechanism of palladium-catalysed cyanoesterification of methyl cyanoformate onto norbornene.

Potential energy surface mapping was completed for the entire catalytic cycle of palladium-catalysed cyanoesterification onto norbornene (NBE) using density functional theory calculations. We found that after the oxidative addition step of the reagent methyl cyanoformate, the reaction proceeds through an insertion of olefin into a Pd(II)-COOMe bond first. Subsequently, reductive elimination occurs by transferring the cyanide group from the Pd center to NBE.

β,β-Diborylated Subporphyrinato Boron(III) Complexes as Useful Synthetic Precursors.

Iridium-catalyzed borylation of B-aryl meso-free subporphyrinato boron(III) complexes (hereinafter referred to simply as subporphyrins) with bis(pinacolato)diboron gave 2,13-diborylated subporphyrins regioselectively, which served as promising synthetic precursors for 2,13-diarylated subporphyrins and doubly β-to-β 1,3-butadiyne-bridged subporphyrin dimers. 2,13-Diarylated subporphyrins display perturbed absorption spectra, depending upon the β-aryl substituents. Doubly 1,3-butadiyne-bridged syn and anti subporphyrin dimers thus prepared exhibit differently altered absorption spectra with split Soret-like bands, which have been accounted for in terms of exciton coupling.

Skeletal rearrangement of cyano-substituted iminoisobenzofurans into alkyl 2-cyanobenzoates catalyzed by B(C6F5)3.

An efficient method for the direct conversion of cyano-substituted iminoisobenzofurans into their corresponding alkyl 2-cyanobenzoates has been developed. This transformation proceeds via cleavage of C-C, C-O, and C-N bonds in starting iminoisobenzofurans. DFT study revealed that intermediate α-iminonitriles are produced in situ via C-C bond formation between 2-iminium benzoates and a cyanide ion.

The origin of exo-selectivity in methyl cyanoformate addition onto the C=C bond of norbornene in Pd-catalyzed cyanoesterification.

A computational investigation has been carried out to elucidate the origin of the exclusive exo-selectivity in the Pd-catalyzed cyanoesterification of strained cyclic olefins, norbornene and norbornadiene. A hybrid density functional was selected for the level of theory with a triple-ζ quality basis set, which was proposed in an earlier study to provide an experimentally sound ground state electronic structure description for palladium(ii) and palladium(iv) complexes from multi-edge X-ray absorption spectroscopic measurements. Given that the product of oxidative addition can be isolated, we focused on the olefin coordination as the earliest possible origin of exo-selectivity.

Synthesis of substituted picenes through Pd-catalyzed cross-coupling reaction/annulation sequences and their physicochemical properties.

A novel and versatile synthetic method for picene derivatives is developed using the Pd-catalyzed intramolecular double cyclization of the corresponding 2,3-bis[(1Z)-2-phenylethenyl]-1,4-dichlorobenzenes, which are readily prepared by Suzuki-Miyaura cross-coupling reactions of polyhalobenzenes with (Z)-arylethenylboronates. The physical properties of the obtained picenes can be modified via introducing a variety of functional groups to the picene framework. All compounds are investigated by UV-vis and fluorescence spectroscopic measurements, CV, and DFT calculations as well as X-ray diffraction analysis.

Experimental study on stability of a high-porosity expanded polytetrafluoroethylene graft in dogs.

Purpose: The purpose of the present study was to evaluate the stability of a high-porosity expanded polytetrafluoroethylene (ePTFE) graft, which has been shown to possess excellent biocompatibility and tissue integration.

Methods: The graft used in the present study was a high-porosity ePTFE graft , which had an average internodal distance of approximately 60 microm and a random node architecture with tortuous path channels extending from the outer to the inner surface. Eleven beagle dogs (each group n = 3 or 4) weighing 10-12 kg were used.