Polymorphism and Light-Driven Forward Movement of TPE Derivative Micro-Crystal due to ArH-pi Interactions Difference.

Aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) are two classes of opposite luminescence phenomena. It is almost impossible to show both AIE and ACQ effect simultaneously by the same molecule. However, here we report that a simple TPE derivative TAP-TPE grows into both AIE crystals and ACQ ones. It is found that equatorial, contact distance-longer and weak ArH-π interactions exist in AIE crystals while vertical, contact distance-shorter and strong ArH-π interactions appear in ACQ crystals. Theoretical calculation of electron density on the interaction atoms unveils that ACQ crystals have much larger change in electron density than AIE ones, suggesting that the intermolecular electron transfer aroused by the strong ArH-π hydrogen bonds leads to ACQ phenomenon. This result provides a new insight into the emission mechanism in aggregation state. Interestingly, due to the ArH-pi interactions difference, only one of five kinds of crystals shows rapid photochromism, and can act as multimode anti-counterfeiting materials. Very exceptionally, for the first time we find that the photochromic micrometric rod-like crystal even makes forward rolling movement as it repeatedly bends and straightens by responding to on and off of the ultraviolet light irradiation, displaying potential for photo-actuator and light-driven micro-vehicle.

Fluorescent TPE Macrocycle Relayed Light-Harvesting System for Bright Customized-Color Circularly Polarized Luminescence.

Artificial systems for sequential chirality transmission/amplification and energy relay are perpetual topics that entail learning from nature. However, engineering chiral light-harvesting supramolecular systems remains a challenge. Here, we developed new chiral light-harvesting systems with a sequential Förster resonance energy transfer process where a designed blue-violet-emitting BINOL (1,1'-Bi-2-naphthol) compound, BINOL-di-octadecylamide (BDA), functions as an initiator of chirality and light absorbance, a new green-emitting hexagonal tetraphenylethene-based macrocycle (TPEM) with aggregation-induced emission serves as a conveyor, and Nile red (NiR) or/and a near-infrared dye, tetraphenylethene (TPE)-based benzoselenodiazole (TPESe), are the terminal acceptors. Benefiting from the close contact and large optical overlap between donors and acceptors at each level, triad and tetrad relaying systems sequentially and efficiently furnish chirality transmission/amplification and energy transfer along the cascaded line BDA-TPEM-NiR (or/and TPESe), leading to bright customized-color circularly polarized luminescence (CPL) and bright white-light-emitting CPL (CIE coordinates: 0.33, 0.34) with an amplified dissymmetry factor (glum) of 3.5 × 10-2 over a wide wavelength range. This work provides a new direction for the construction of chiral light-harvesting systems for a broad range of applications in chiroptical physics and chemistry.

Gastroscopic results for the asymptomatic, average-risk population in Northern China: a cross-sectional study of 60,519 adults.

BACKGROUND: Studies on average-risk individuals undergoing gastroscopy screening in China are scarce. OBJECTIVE: To determine and compare the prevalence of lesions found by gastroscopy and the association between sex, age, Helicobacter pylori infection and gastric premalignant lesions. METHODS: Gastroscopy results were analysed for 60,519 individuals enrolled from January 2013 to December 2019. RESULTS: The median age was 49.84 years (SD, 9.47 years) for women and 48.90 years (SD, 8.82 years) for men, and the ratio of females to males was 35.10% (n = 21,240) to 64.90% (n = 39,279). The most common lesions detected by endoscopy were chronic gastritis, reflux oesophagitis, duodenitis and gastric polyps, detected in 24.48%, 10.28%, 3.96% and 3.61%, respectively. Oesophageal cancer and gastric cancer were detected in 0.33% and 0.47% of patients, respectively. The prevalence of chronic gastritis increased with age and was higher in males than in females (26.47% [n = 10396] versus 20.80% [n = 4417], p < .001). The prevalence of gastric ulcers was highest in the elderly group, and the H. pylori infection rate of gastric ulcer patients was 47.28%. The prevalence of gastric polyps was higher in females than in males (5.47% [n = 1161] versus 2.61% [n = 1024], p < .001), and the H. pylori infection rate in inflammatory polyp patients was higher than that in fundic gland polyp patients (28.32% [n = 442] versus 7.29% [n = 29], p < .001). CONCLUSION: The prevalence of upper gastrointestinal endoscopic lesions is high in the asymptomatic population undergoing physical examination and is associated with sex, age, and H. pylori infection.

Hindered Tetraphenylethylene Helicates: Chiral Fluorophores with Deep-Blue Emission, Multiple-Color CPL, and Chiral Recognition Ability.

New hindered tetraphenylethylene (TPE) helicates with substitution at 2,6-position of phenyl rings were designed and synthesized. Due to the increased hindrance, the TPE helicates emit strong deep-blue to violet fluorescence both in the solid state and in solution, and could be resolved into enantiomers that emit strong and multicolor circularly polarized luminescence (CPL), and exhibit a high enantioselective recognition of chiral tartaric acid and its derivatives. Surprisingly, the derived helicate tetramines possess amino groups with an unpredented planar structure and sp2 -hybridized nitrogen, arousing the change between AIE effect and ACQ phenomenon through photoinduced electron transfer (PET). With advantages of short synthetic route, many modification positions, deep-blue to violet emission, wide CPL tuning, and high chiral recognition ability, the hindered TPE helicates show broad prospects as chiral materials.

NUDT21 knockdown inhibits proliferation and promotes apoptosis of pancreatic ductal adenocarcinoma through EIF2 signaling.

The NUDT family is thought to play an important role in cancer growth and progression. However, the clinicopathologic significance and potential role of nucleotide diphosphate-linked X-component motif 21, NM_007006 (NUDT21) in pancreatic ductal adenocarcinoma (PDAC) remains largely unknown. In this study, we observed that NUDT21 was frequently up-expressed in PDAC. Clinical data revealed that its level positively correlated with poor survival of patients with PDAC. We found that knockdown of NUDT21 significantly inhibited cell proliferation and promoted apoptosis both in vitro and in vivo. Screening by microarray analysis and verifying by Western blot, we found that the EIF2 signaling pathway represented the main molecular mechanism underlying the effects of NUDT21 knockdown in PANC-1 cells, and PKR, HSPA5, EIF4E and DDIT3 may be its target genes. Thus, our results revealed for the first time that NUDT21, a valuable marker of PDAC prognosis, promotes tumor proliferation, inhibits cells apoptosis and might represent a potential target for gene-based therapy.

Macrocycles and cages based on tetraphenylethylene with aggregation-induced emission effect.

Organic molecules with an aggregation-induced emission (AIE) effect have recently been attracting more and more attention due to their colossal potential in solid emitters and chemo/biosensors. The number and variety of AIEgen compounds are expanding very rapidly to obtain better application performance and a wider area of application. Among AIEgen systems, tetraphenylethylene (TPE) and its derivatives are the class that have received the most extensive study and the most rapid development because of their facile synthesis. Due to its C2 symmetry and at least tetratopic reaction positions, the TPE unit is also an ideal building block for constructing macrocycles and cages. The resultant cyclic TPE compounds have exhibited many exceptional performances that are difficult to access in their open chain counterparts, such as AIE enhancement, improvement in selectivity and sensitivity as sensors, emission tuning by guests, supramolecular catalysis, further disclosure of the AIE mechanism, molecular adsorption, storage and release, the propeller-like conformation exploitation of the TPE unit in chiral materials and so on. Recently, therefore, a large variety of studies about the synthesis, properties and application research of TPE macrocycles and cages have been reported. These TPE macrocycles and cages significantly expand the research area for the AIE phenomenon and its applications, and represent a development of the AIE area. However, up to now, no review of TPE macrocycles and cages has been available. Thus, this review serves as a summary of the designs, synthesis, photophysical properties, self-assembly, applications and prospects of TPE macrocycles and cages.

Tetraphenylethylene Foldamers with Double Hairpin-Turn Linkers, TNT-Binding Mode and Detection of Highly Diluted TNT Vapor.

Tetraphenylethylene (TPE) foldamers with double hairpin-turn linkers showing an aggregation-induced emission (AIE) effect have been synthesized for the first time. A crystal structure of a foldamer-TNT complex has been obtained, enabling unprecedented direct observation of the interactions between TNT molecules and the chromophores of the foldamer. Instead of π-π stacking interactions, which have often been considered to be the key mechanism in the binding of TNT by chromophoric receptors, strong n-π interactions between the nitro groups of TNT and the aromatic rings of the foldamer have been found. Exceptionally, by addition of 1 % NaF to a suspension of the foldamer in H2 O/THF (95:5), the fluorescence quenching efficiency by TNT vapor significantly increased from about 20 % to more than 90 %. Even after diluting TNT-saturated air at 25 °C by a factor of 2×104 , an obvious quenching response was observed, indicating that ultratrace TNT vapor (down to 3.4 fg per mL of air) could be detected.

Selective Host-Guest Co-crystallization of Pyridine-Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co-crystals.

Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.

The Fixed Propeller-Like Conformation of Tetraphenylethylene that Reveals Aggregation-Induced Emission Effect, Chiral Recognition, and Enhanced Chiroptical Property.

The propeller-like conformation of tetraphenylethylene (TPE) with aggregation-induced emission (AIE) effect was partially and completely fixed by intramolecular cyclization for the first time. The immobilization of propeller-like conformation was found to show great advantages in determining the enantiomer purity, identifying the chiral amines. The completely fixed conformers are resolved into M- and P-enantiomer, which showed mirror imaged CD and almost quantitative fluorescence quantum yield. Furthermore, it also showed a mirror and large circularly polarized luminescence dissymmetric factor, depending on the helicity of the enantiomer. The result provides the most direct and persuasive evidence for AIE via the restriction of intramolecular rotation and finds the new insight of the compounds in chiroptical property.

Enantioselective Recognition for Many Different Kinds of Chiral Guests by One Chiral Receptor Based on Tetraphenylethylene Cyclohexylbisurea.

A neutral chiral receptor based on TPE cyclohexylbisurea was synthesized and could discriminate the enantiomers of many different kinds of chiral reagents, including chiral acidic compounds, basic compounds, amino acids, and even neutral alcohols. The (1)H NMR spectra disclosed that the ability of chiral recognition could be ascribed to the multiple hydrogen bonds and CH-π interactions between the TPE urea receptor and the enantiomer of the chiral guest, which led to the selective aggregation of the receptor with one of the two enantiomers. This result exhibited a great potential in enantiomer discernment and high-throughput analysis of enantiomer composition of these chiral analytes by one chiral AIE molecule.

Fluorescence Turn-on Enantioselective Recognition of both Chiral Acidic Compounds and α-Amino Acids by a Chiral Tetraphenylethylene Macrocycle Amine.

New chiral tetraphenylethylene (TPE) macrocycles bearing optically pure amine groups were synthesized and found to have a discriminating ability between the two enantiomers of not only chiral acidic compounds but also α-amino acids by enantioselective aggregation and aggregation-induced emission (AIE) effects. NMR spectra, including 2D-NOESY, disclosed that the host-guest interaction of the macrocycle receptor played a key role in addition to the acid-base interactions.

A Porous Tricyclooxacalixarene Cage Based on Tetraphenylethylene.

A quadrangular prismatic tricyclooxacalixarene cage 1 based on tetraphenylethylene (TPE) was efficiently synthesized by a one-pot S(N)Ar condensation reaction. As a result of the porous internal structure in the solid state, cage 1 exhibited a good CO2 uptake capacity of 12.5 wt% and a high selectivity for CO2 over N2 adsorption of 80 (273 K, 1 bar) with a BET surface area of 432 m(2) g(-1). Formation of cage 1 led to the fluorescence of TPE being switched on in solution. The system was employed as a single-molecule platform to study the mechanism of aggregation-induced emission (AIE) by examining the restriction of intramolecular rotation (RIR).

Highly sensitive and selective detection of nitrophenolic explosives by using nanospheres of a tetraphenylethylene macrocycle displaying aggregation-induced emission.

A tetraphenylethylene (TPE) Schiff-base macrocycle showing an aggregation-induced emission (AIE) effect has been synthesized, which could aggregate into nanospheres and emit yellow fluorescence in aqueous media. By virtue of its AIE effect, the macrocycle showed a sensitive and selective response to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP) among a number of nitroaromatic compounds, which could be used to detect TNP and DNP at nanomolar levels. Moreover, it exhibited a superamplified quenching effect with DNP but not with TNP, providing a possible means of discriminating these two compounds. In comparison with open-chain TPE Schiff-bases, the cavity of the macrocycle is essential for the selectivity for DNP over TNP. In addition, quantitative analyses of both DNP and TNP in real water samples and qualitative detection of these two analytes in the solid state by the macrocycle have been tested. The reliability of the quantitative analysis has been confirmed by HPLC. Our findings demonstrate that the TPE Schiff-base macrocycle has great potential as an excellent sensor for DNP and TNP.

Monomer emission and aggregate emission of an imidazolium macrocycle based on bridged tetraphenylethylene and their quenching by C60.

A novel imidazolium macrocycle based on bridged tetraphenylethylene (TPE) was synthesized. Because it bears the bridged TPE units, this macrocycle not only displays an aggregation-induced emission (AIE) effect but also exhibits monomer emission, which is very rare in AIE compounds. With aggregation of the macrocycle, the aggregate emission increases while the monomer emission decreases. It was found that this imidazolium macrocycle can form a stable 2:1 complex with C60, which gives rise to quenching of both the aggregate emission and the monomer emission. Unexpectedly, the aggregate emission exhibited a higher quenching efficiency than the monomer emission, probably because one adsorbed C60 molecule could affect more macrocycle molecules in the aggregate.

Tetraphenylethylene-based expanded oxacalixarene: synthesis, structure, and its supramolecular grid assemblies directed by guests in the solid state.

A novel TPE-based expanded oxacalixarene with typical aggregation-induced emission properties was synthesized by the SNAr reaction of dihydroxytetraphenylethylene with 2,6-dichloropyrazine. The conformation of the oxacalixarene is adjusted by the encapsulated guests (benzene or THF), which results in different supramolecular grid structures in the solid state.

Asymmetric Synthesis of Tetraphenylethylene Helicates and Their Full-Color CPL Emission with High glum and High Fluorescence Quantum Yield.

Tetraphenylethylene (TPE) helicates with single helical handedness not only owe high fluorescence quantum yield but also possess good helical chirality, showing an excellent circularly polarized luminescence active material. In this work, a new method for directly obtaining single-handed TPE helicates has been developed. By using chiral p-phenylenediamine derivatives as an intramolecular cyclization reagent of TPE, the single-handed propeller-like conformation and stable helical chirality of the TPE unit were obtained, avoiding complicated and expensive HPLC chiral column separation. The as-prepared chiral TPE helicates displayed strong emission with an almost quantitative fluorescence quantum yield (Φf) and strong circularly polarized luminescence (CPL). In addition, the chirality and CPL signals of the TPE helicates could be significantly magnified by the helical arrangement together with 4'-pentyl-4-biphenylcarbonitrile (5CB) liquid crystal molecules. Moreover, full-color CPL emissions with both a high absolute CPL dissymmetrical factor up to 0.43 and high Φf were afforded.

Effect of Home Blood Pressure Telemonitoring Plus Additional Support on Blood Pressure Control: A Randomized Clinical Trial.

Objective: Current clinical evidence on the effects of home blood pressure telemonitoring (HBPT) on improving blood pressure control comes entirely from developed countries. Thus, we performed this randomized controlled trial to evaluate whether HBPT plus support (patient education and clinician remote hypertension management) improves blood pressure control more than usual care (UC) in the Chinese population. Methods: This single-center, randomized controlled study was conducted in Beijing, China. Patients aged 30-75 years were eligible for enrolment if they had blood pressure [systolic (SBP) ≥ 140 mmHg and/or diastolic (DBP) ≥ 90 mmHg; or SBP ≥ 130 mmHg and/or DBP ≥ 80 mmHg with diabetes]. We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks. The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure. Results: Totally, 172 patients completed the study, the HBPT plus support group ( n = 84), and the UC group ( n = 88). Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group. The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the 12th week of follow-up. Additionally, the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group. Conclusion: HBPT plus additional support results in greater blood pressure reduction, better blood pressure control, a higher proportion of dipper blood pressure patterns, lower blood pressure variability, and higher drug adherence than UC. The development of telemedicine may be the cornerstone of hypertension management in primary care.

Effect of carboxylic acid on micelles of a neutral amphiphilic dendro-calix[4]arene.

An amphiphilic calix[4]arene bearing branched 3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide groups at the upper rim was synthesized and could increase the solubility of naproxen and ibuprofen in water through hydrogen bonding and π-π stacking interactions. The interactions between amphiphilic calix[4]arene and carboxylic acids such as naproxen and ibuprofen could reverse the direction of the branched substituents and change the shape and size of calixarene micelles from solid to hollow or linear ones.

[A cross-sectional survey of crab intolerance positive rate and its determinants in healthy medical examination population in Beijing].

OBJECTIVE: To explore the positive rate of crab intolerance and its related factors in a healthy physical examination population in Beijing, China. METHODS: A cross-sectional survey was carried out from August 1, 2008 to July 30, 2009. It recruited a total of 12 765 adults with crab intolerance at Health Sciences Center, Chinese PLA General Hospital. The epidemiological data were entered into computer by two persons and organized by Epidata3.0. Non-conditional Logistic regression model was used to calculate the values of odd ratio (OR) and 95%CI. Statistic analysis was performed by SPSS 13.0. RESULTS: The incidence rate of crab intolerance was 24.5% (3128/12 765) and increased with age. Grades of crab intolerance were associated with age and gender and there was a linear correlation tendency (P < 0.05). Incidence rate of crab intolerance in females (27.5%, 1077/3912) was higher than that of males (23.2%, 2051/8853). Multiple regression analysis showed that crab intolerance was correlated with age, gender, body mass index and helicobacter infections(all P < 0.05). In comparison with age group < 40 years old, the values of OR (95%CI) of age groups 41 - 50, 51 - 60 and > 60 years old were 1.224 (1.095 - 1.368), 1.616 (1.431 - 1.827) and 2.177 (1.799 - 2.634) respectively. In comparison with males, the OR (95%CI) of females was 1.286 (1.174 - 1.408). The OR (95%CI) of Helicobacter pylori infections was 1.303(1.201 - 1.413). In comparison with normal weighters, the OR (95%CI) of obese subjects was 1.154 (1.026 - 1.298). CONCLUSIONS: Crab intolerance may be correlated with age, gender, Helicobacter pylori infections and body mass index. Health education should be targeted at its characteristics.

[Body composition analysis among adults with different body weights].

OBJECTIVE: To explore the characteristics of body composition among male and female adults with different body weights. METHODS: A total of 61 379 healthy adults (39 855 males and 21 527 females) were referred to our health examination center between May 2005 and February 2011. Body mass index (BMI) and body composition contents of fat, water, muscle, protein and mineral salt were measured by anthropometric measurements and bioelectrical impedance analysis (BIA). The data were analyzed among groups divided by gender, age and BMI. RESULTS: (1) The prevalence of overweight and obesity defined by BMI was significantly higher in the male group than the female of the same age group under 70 years old (all P < 0.01). (2) Within a certain age range (< 60 in males, < 70 in females), the prevalence of both overweight and obesity defined by BMI increased with age (all P < 0.01). (3) The fat mass percentage was significantly higher in females than in males of the same age group. The difference became more and more significant with advancing age. And the most significant difference was found in the upper 70 years old group (fat mass rate of males vs females, 24% ± 7% vs 36% ± 6%, P < 0.01). (4) Body fat mass percentage progressively elevated with increases of BMI while there was a decreasing trend of other body composition contents. The total male subjects had higher percentage of muscle, water and mineral salt than females (percentage of muscle, water and mineral salt of males vs females, 0.708 ± 0.066 vs 0.664 ± 0.063, 0.520 ± 0.044 vs 0.474 ± 0.042, 0.040 ± 0.004 vs 0.036 ± 0.004, all P < 0.01) while the percentage of protein was higher in the total female group (P < 0.01). CONCLUSIONS: Females has more fat mass than males under the same BMI. So it is more reasonable to introduce adiposity for the evaluation of obesity, especially in females.