Role of Computed Tomography in Predicting Programmed Death Ligand-1 Positivity in Gastric Adenocarcinoma.

Objective: To examine the association between computed tomography (CT) imaging characteristics and programmed death ligand-1 (PD-L1) expression in patients with gastric adenocarcinoma (GAC), and to develop a nomogram model for prediction.

Methods: The patients were randomly allocated into a training set and a validation set at a ratio of 7:3. The training set was further divided into a PD-L1 positive group and a PD-L1 negative group, based on the combined positive score (CPS).

L-Amino acid ester as a biomimetic reducing agent for the reduction of unsaturated CC bonds.

The first example of an efficient protocol for the reduction of disubstituted methyleneindolinones, isoindigos and tetrasubstituted olefins for the synthesis of 3-substituted 2-oxindoles, dihydroisoindigos and tetrasubstituted ethane derivatives using an L-amino acid ester as an attractive biomimetic reducing agent has been developed. This new protocol has the advantages of mild reaction conditions without the need for any metal catalysts, a broad substrate scope (31 examples), excellent yields (90-98%) and good functional group tolerance, providing an operationally simple and practically useful methodology for reductive reactions. The L-amino acid derivative, which is cheap, nontoxic and easy to handle, serves as a new biomimetic reducing agent for use in organic chemistry, providing a novel and promising approach for future applications in reductive reactions.

Umpolung Strategy for the One-Pot Synthesis of Highly Steric Bispirooxindoles via the l-Amino Acid Ester-Promoted In Situ Reduction/Nucleophilic Addition/Cyclization Cascade Reaction.

On the basis of a novel umpolung strategy, an efficient l-amino acid ester-mediated in situ reduction of 2-(2-oxoindolin-3-ylidene)malononitrile and sequential nucleophilic addition/cyclization cascade reaction is reported. Various densely substituted cyclopentene bispirooxindoles and dihydrofuran bispirooxindoles with two quaternary spirocenters were constructed in high yields (≤93%) with excellent diastereoselectivities (>20:1 dr). The method has advantages of readily available starting materials, mild reaction conditions, a one-pot process, a metal-free biomimetic reducing agent, a wide substrate scope, and operational simplicity (single filtration without column chromatography).

Synthesis of Dipeptide, Amide, and Ester without Racemization by Oxalyl Chloride and Catalytic Triphenylphosphine Oxide.

An efficient triphenylphosphine oxide-catalyzed amidation and esterification for the rapid synthesis of a series of dipeptides, amides, and esters is described. This reaction is applicable to challenging couplings of hindered carboxylic acids with weakly nucleophilic amines or alcohols, giving the products in good yields (67-90%) without racemization. This system employs the highly reactive intermediate PhPCl as the activator of the carboxylate in a catalytic manner and drives the reaction to completion in a short reaction time (less than 10 min).

Organocatalytic, Enantioselective, Polarity-Matched Ring-Reorganization Domino Sequence Based on the 3-Oxindole Scaffold.

A one-pot squaramide-catalyzed enantioselective ring-reorganization domino sequence (Michael addition/intramolecular ring-opening/lactamization) of 3-hydroxyoxindole and methyleneindolinone, which can be readily derived from 3-oxindole, has been established in this work. As a result, novel polycyclic quinolinone-spirooxindoles bearing three contiguous chiral centers were efficiently and step-economically assembled under mild conditions in high yields (up to 97%) with excellent enantioselectivities (up to >99% ee) and moderate to good diastereoselectivities (up to >95:5 dr).

A One-Pot Ring-Opening/Ring-Closure Sequence for the Synthesis of Polycyclic Spirooxindoles.

One-pot ring-opening/ring-closure process of combining methyleneindolinone with 3-aminooxindole has been developed in this work. Novel polycyclic spirooxindoles were efficiently assembled under mild conditions in high yields (up to 95 %) with moderate to good diastereoselectivities (up to >95:5 d.r.

Photocatalytic reductive radical-radical coupling of N,N'-cyclicazomethine imines with difluorobromo derivatives.

A visible-light-induced difluoroalkylation of N,N'-cyclicazomethine imine was successfully realized through a novel photoredox radical-radical cross-coupling reaction. This developed protocol exhibits high functional group tolerance and affords a variety of difluorinated 3-pyrazolidinone scaffolds. Extensive mechanistic investigations have been undertaken, well revealing the involvement of a reductive radical-radical coupling pathway.

Generation and Characterization of Fibroblast-Specific Basigin Knockout Mice.

Basigin is a well-known extracellular stimulator of fibroblasts and may confer resistance to apoptosis of fibroblasts in vitro under some pathological status, but its exact function in fibroblasts and the underlying mechanism remain poorly understood. The systematic Basigin gene knockout leads to the perinatal lethality of mice, which limits the delineation of its function in vivo. In this study, we generated a fibroblast-specific Basigin knock-out mouse model and demonstrated the successful deletion of Basigin in fibroblasts.

L-Pyroglutamic Sulphonamide as Hydrogen-Bonding Organocatalyst: Enantioselective Diels-Alder Cyclization to Construct Carbazolespirooxindoles.

Hydrogen-bonding organocatalysts L-pyroglutamic sulphonamides were readily synthesized for the first time by fully exploiting the potentials of L-pyroglutamic acid. The newly designed catalyst was successfully applied in catalyzing asymmetric Diels-Alder cyclization of methyleneindolinones with 2-vinyl-1H-indoles to efficiently assemble carbazolespirooxindoles in excellent stereoselectivity (up to 99% ee, >20:1 dr) and yields (up to 99%). Mechanistic studies disclosed that the well-designed hydrogen-bonding modes between L-pyroglutamic sulphonamide and substrates were crucial for stereocontrol in the cyclization.

An Analysis of Prognostic Factors in Patients with Ovarian Malignant Germ Cell Tumors Who Are Treated with Fertility-Preserving Surgery.

Background/aims: To analyze the clinicopathological factors that affect the prognosis and fertility of patients with malignant ovarian germ cell tumors (MOGCTs).

Methods: The medical records and follow-up data of 106 patients with MOGCTs who were treated at The Affiliated Tumor Hospital of Guangxi Medical University between January 1986 and December 2010 were enrolled in this study. A Kaplan-Meier analysis was used to analyze the survival curves.

Synthesis of pyrrolo(spiro-[2.3']-oxindole)-spiro-[4.3"]-oxindole via 1,3-dipolar cycloaddition of azomethine ylides with 3-acetonylideneoxindole.

A series of novel dispirooxindole derivatives, 3-acetyl-5-phenyl-pyrrolo(spiro-[2.3']-1'-benzyl-oxindole)-spiro-[4.3"]-1"-benzyl-oxindoles, were synthesized via 1,3-dipolar cycloaddition of the azomethine ylide with 3-acetonylideneoxindole in high regioselectivities and yields.

[Prognostic factors analysis in patients with ovarian malignant germ cell tumor treated with fertility-preserving surgery].

Objective: To analyse the clinicopathologic factors affecting prognosis and fertility of patients with malignant ovarian germ cell tumor (MOGCT).

Methods: The medical records and follow up data of 106 patients with MOGCT treated at Affiliated Tumor Hospital of Guangxi Medical University between January 1986 and December 2010.Kaplan-Meier method was used to analyse survival curves.