[A new nortriterpenoid from mastic].

Ten compounds were separated by various modern chromatographic methods from mastic. They were identified by HR-ESI-MS, IR, UV, NMR, quantum chemical calculation of NMR(qcc-NMR) and comparison with reported data in literature as 17β-hydroxy-28-norolean-18-en-3-one(1), 28-norolean-12,17-dien-3,11-dione(2), 28-norolean-16,18-dien-3-one(3),(24Z)-26-hydroxy-7,24-dientirucalla-3-one(4), masticadienonic acid(5)、masticadienolic acid(6)、erythrodiol(7), 3β,28-dihydroxyoleana-11,13(18)-diene(8), 3-oxo-olean-9(11),12-dien-28-oic acid(9), and 12-oleane-3,11-dione(10). Among them, compound 1 was a novel compound and compound 2 was a novel natural product.

Two-Step Chirality Transfer to Twisted Assemblies: Synergistic Interplay of Chiral and Aggregation Interactions.

Chirality plays a pivotal role in both the origin of life and the self-assembly of materials. However, the governing principles behind chirality transfer in hierarchical self-assembly across multiple length scales remain elusive. Here, we propose a concise and versatile simulation strategy using the patchy particle chain model to investigate the self-assembly of rods interacting through chiral and aggregation interactions.

Association between psychiatric disorders and irritable bowel syndrome: A bidirectional Mendelian randomization study.

Objective: Previous studies have suggested that irritable bowel syndrome (IBS) is strongly associated with psychiatric disorders. However, it is unclear whether this association is causal, concomitant, or accidental. Thus, we performed Mendelian randomization (MR) analysis to evaluate the causal effects of several psychiatric disorders on IBS.

Relative kinetic stability of defect patterns in two-dimensional nematic liquid crystals with rectangular confinement.

Guiding and dynamically modulating topological defects are critical challenges in defect engineering of liquid crystals. Here, we employ molecular dynamics simulations to investigate the transition dynamics and relative kinetic stability of defect patterns in two-dimensional nematic Gay-Berne liquid crystals confined within rectangular geometries. We observe the formation of various defect patterns including long-axis, diagonal, X-shaped, composite, and bend configurations under different confinement conditions.

Seven New Noroleanane Triterpenoids from Mastic and Their NO Inhibitory and Cytotoxic Activities.

Mastic is a natural resin produced by Pistacia lentiscus L. (Anacardiaceae) with high medicinal value and have been traditionally used as Uighur imported medicine for centuries. In this study, 16 triterpenoids including seven new noroleanane triterpenoids (1-7), along with nine known oleanane triterpenoids (8-16), were isolated from the mastic.

A Ligand-Directed Spatial Regulation to Structural and Functional Tunability in Aggregation-Induced Emission Luminogen-Functionalized Organic-Inorganic Nanoassemblies.

Aggregation-induced emission luminogen (AIEgen)-functionalized organic-inorganic hybrid nanoparticles (OINPs) are an emerging category of multifunctional nanomaterials with vast potential applications. The spatial arrangement and positioning of AIEgens and inorganic compounds in AIEgen-functionalized OINPs determine the structures, properties, and functionalities of the self-assembled nanomaterials. In this work, a facile and general emulsion self-assembly tactic for synthesizing well-defined AIEgen-functionalized OINPs is proposed by coassembling alkane chain-functionalized inorganic nanoparticles with hydrophobic organic AIEgens.

Surface Engineering and Programmed Self-Assembly of Silica Nanoparticles with Controllable Polystyrene/Poly(4-vinybenzyl azide) Patches.

The programmed self-assembly of patchy nanoparticles (NPs) through a bottom-up approach is an efficient strategy for producing highly organized materials with a predetermined architecture. Herein, we report the preparation of di- and trivalent silica NPs with polystyrene (PS)/poly(4-vinylbenzyl azide) (PVBA) patches and assemble them in a THF mixture by lowering the solvent quality. Silica-PS/PVBA colloidal hybrid clusters were synthesized through the seeded growth emulsion copolymerization of styrene and 4-vinylbenzyl azide (VBA) in varying ratios.

Exploring mechanical properties and failure mechanisms of aramid and PBO crystals through molecular dynamics simulations.

Molecular dynamics simulations were used to analyze the mechanical properties and failure processes of poly(p-phenylene-terephthalamide) (PPTA), poly(p-phenylene-benzimidazole-terephthalamide) (PBIA), PBIA-PPTA (formed by 1:1 copolymerization of PPTA and PBIA), and poly(p-phenylene-benzobisoxazole) (PBO) crystals at different strain rates and temperatures. The failure stress and strain were found to be linear with the temperature and logarithmic strain rate. Moreover, based on the kinetic theory of fracture and the comprehensive simulation results, we formulated a model that describes the failure stress of the aforementioned crystals under varying strain rates and temperatures.

Cloning and functional study of , which is the critical gene of photosynthesis in soybean.

Light provides energy for photosynthesis and is also an important environmental signal that regulates plant growth and development. Ribose-5-phosphate isomerase plays a crucial role in photosynthesis. However, ribose-5-phosphate isomerase has yet to be studied in soybean photosynthesis.

Helical structures of achiral liquid crystals under cylindrical confinement.

Confined liquid crystals (LCs) exhibit complex and intriguing structures, which are fascinating fundamental problems in soft matter. The helical structure of cylindrical cavities is of great importance in LC studies, particularly for their application in optical devices. In this study, we employ molecular dynamics simulations to explore the behavior of achiral smectic-B LCs confined in narrow cylindrical cavities, where geometric frustration plays an important role.

Defect transition of smectic liquid crystals confined in spherical cavities.

The formation and transformation of defects in confined liquid crystals are fascinating fundamental problems in soft matter. Here, we use molecular dynamics (MD) simulations to study ellipsoidal liquid crystals (LCs) confined in a spherical cavity, which significantly affects the orientation and translation of LC molecules near the surface. The liquid-crystal droplet can present the isotropic to smectic-B phase transition through the smectic-A phase, as the number density of the LC molecules increases.

External field induced defect transformation in circular confined Gay-Berne liquid crystals.

Normally, defects in two-dimensional, circular, confined liquid crystals can be classified into four types based on the position of singularities formed by liquid crystal molecules, i.e., the singularities located inside the circle, at the boundary, outside the circle, and outside the circle at infinity.

Immobilization of Actinobacillus succinogenes on nano- and micro-fiber membranes for efficient and robust production of succinic acid.

This work aimed to study the efficiency of nano- and micro- fiber membranes in immobilizing Actinobacillus succinogenes CCTCC M2012036 for succinic acid production. Among the four kinds of electrospun nanofiber membranes of cellulose acetate, chitosan, poly(vinyl alcohol) (PVA) and chitosan-PVA, the cellulose acetate nanofiber membrane-immobilized cells performed the best with a succinic acid concentration and yield to be 27.3 ± 3.

A Comprehensive Appraisal of Meta-Analyses of Exercise-Based Stroke Rehabilitation with Trial Sequential Analysis.

Meta-analysis is a common technique used to synthesise the results of multiple studies through the combination of effect size estimates and testing statistics. Numerous meta-analyses have investigated the efficacy of exercise programmes for stroke rehabilitation. However, meta-analyses may also report false-positive results because of insufficient information or random errors.

Research progress in targeted therapies for gastric cancer.

Patients with advanced gastric cancer experience rapid disease progression with limited survival, high mortality, and a lack of surgical options. Thus, radiochemotherapy or a combination of chemotherapeutics with targeted therapy is the mainstay of treatment. In comparison to the treatment of other malignant tumors, in gastric cancer, the development of molecularly targeted drugs has been relatively slow.

Colloidal cubic diamond photonic crystals through cooperative self-assembly.

Colloidal cubic diamond crystals with low-coordinated and staggered structures could display a wide photonic bandgap at low refractive index contrasts, which makes them extremely valuable for photonic applications. However, self-assembly of cubic diamond crystals using simple colloidal building blocks is still considerably challenging, due to their low packing fraction and mechanical instability. Here we propose a new strategy for constructing colloidal cubic diamond crystals through cooperative self-assembly of surface-anisotropic triblock Janus colloids and isotropic colloidal spheres into superlattices.

A chiral smectic phase induced by an alternating external field.

Using simple achiral building blocks modulated by an external field to achieve chiral liquid crystal phases remains a challenge. In this study, a chiral helix liquid crystal phase is obtained for a simple Gay-Berne ellipsoid model under an alternating external field by using molecular dynamics simulations. Our results show that the chiral helix liquid crystal phase can be observed in a wide range of external field strengths when the oscillation period is smaller than the rotational characteristic diffusion timescale of ellipsoids.

A highly selective 2''--glycosyltransferase from and biosynthesis of isovitexin 2''--glucoside.

A novel and efficient 2''--glycosyltransferase ZjOGT38 was identified from . It could regio-selectively glycosylate 2-hydroxyflavanone -glycosides. ZjOGT38 allowed biosynthesis of isovitexin 2''--glucoside in .

Transition kinetics of defect patterns in confined two-dimensional smectic liquid crystals.

Topological defects in liquid crystals under confined geometries have attracted extensive research interests. Here, we perform molecular dynamics simulations to investigate the formation and transition of defect patterns in two-dimensional smectic Gay-Berne liquid crystals with a simple rectangular confinement boundary. Two typical types of defect patterns, bridge and diagonal defect patterns, are observed, which can be transformable continuously between each other over time.

Intercluster Exchange-Stabilized Novel Complex Colloidal χ Phase.

Designing complex cluster crystals with a specific function using simple colloidal building blocks remains a challenge in materials science. Herein, we propose a conceptually new design strategy for constructing complex cluster crystals via hierarchical self-assembly of simple soft Janus colloids. A novel and previously unreported colloidal cluster-χ (χ) phase, which resembles the essential structural features of α-manganese but at a larger length scale, is obtained through molecular dynamics simulations.

Softness-Enhanced Self-Assembly of Pyrochlore- and Perovskite-like Colloidal Photonic Crystals from Triblock Janus Particles.

It remains extremely challenging to build three-dimensional photonic crystals with complete photonic bandgaps by simple and experimentally realizable colloidal building blocks. Here, we demonstrate that particle softness can enhance both the self-assembly of pyrochlore- and perovskite-like lattice structures from simple deformable triblock Janus colloids and their photonic bandgap performances. Dynamics simulation results show that the region of stability of pyrochlore lattices can be greatly expanded by appropriately increasing softness, and the perovskite lattices are unexpectedly obtained at enough high softness.

Kinetics-controlled design principles for two-dimensional open lattices using atom-mimicking patchy particles.

The design and discovery of new two-dimensional materials with desired structures and properties are always one of the most fundamental goals in materials science. Here we present an atom-mimicking design concept to achieve direct self-assembly of two-dimensional low-coordinated open lattices using three-dimensional patchy particle systems. Besides honeycomb lattices, a new type of two-dimensional square-octagon lattice is obtained through rational design of the patch configuration of soft three-patch particles.

Enthalpy-driven self-assembly of amphiphilic Janus dendrimers into onion-like vesicles: a Janus particle model.

Synthetic vesicles of amphiphilic Janus dendrimers are known as dendrimersomes. The understanding of the conditions and formation mechanism of dendrimersomes is meaningful for further controlling the structures. Herein, the characteristics of the self-assembly of amphiphilic Janus dendrimer/water solutions into unilamellar and onion-like dendrimersomes are studied by molecular dynamics simulations via a spherical single-site Janus particle model.

Secondary acute promyelocytic leukemia following chemotherapy for gastric cancer: a case report.

Therapy-related acute myeloid leukemia (t-AML) refers to a heterogeneous group of myeloid neoplasms that develop in patients following extensive exposure to either cytotoxic agents or radiation. The development of t-AML has been reported following treatment of cancers ranging from hematological malignancies to solid tumors; however, to our knowledge, t-AML has never been reported following treatment of gastric cancer. In this study, we report the development of t-acute promyelocytic leukemia in a cT4N1M0 gastric cancer patient after an approximate 44 mo latency period following treatment with 4 cycles of oxaliplatin (OXP) (85 mg/m(2) on day 1) plus capecitabine (1250 mg/m(2) orally twice daily on days 1-14) in combination with recombinant human granulocyte-colony stimulating factor treatment.