Synergistic Effects of Icariin and Extracellular Vesicles Derived from Rabbit Synovial Membrane-Derived Mesenchymal Stem Cells on Osteochondral Repair via the Wnt/ß-Catenin Pathway.

Objectives: Osteochondral defects (OCDs) are localized areas of damaged cartilage and underlying subchondral bone that can produce pain and seriously impair joint function. Literature reports indicated that icariin (ICA) has the effect of promoting cartilage repair. However, its mechanism remains unclear. Here, we explored the effects of icariin and extracellular vesicles (EVs) from rabbit synovial-derived mesenchymal stem cells (rSMSCs) on repairing of OCDs. Materials and Methods: Rabbit primary genicular chondrocytes (rPGCs), knee skeletal muscle cells (rSMCKs), and rSMSCs, and extracellular vesicles derived from the latter two cells (rSMCK-EVs and rSMSC-EVs) were isolated and identified. The rPGCs were stimulated with ICA, rSMSC-EVs either separately or in combination. The rSMCK-EVs were used as a control. After stimulation, chondrogenic-related markers were analyzed by quantitative RT-PCR and western blotting. Cell proliferation was determined by the CCK-8 assay. The preventative effects of ICA and SMSC-EVs in vivo were determined by H&E and toluidine blue staining. Immunohistochemical analyses were performed to evaluate the levels of COL2A1 and ß-catenin in vivo. Results. In vitro, the proliferation of rPGCs was markedly increased by ICA treatment in a dose-dependent manner. When compared with ICA or rSMSC-EVs treatment alone, combined treatment with ICA and SMSC-EVs produced stronger stimulative effects on cell proliferation. Moreover, combined treatment with ICA and rSMSC-EVs promoted the expression of chondrogenic-related gene, including COL2A1, SOX-9, and RUNX2, which may be via the activation of the Wnt/ß-catenin pathway. In vivo, combined treatment with rSMSC-EVs and ICA promoted cartilage repair in joint bone defects. Results also showed that ICA or rSMSC-EVs both promoted the COL2A1 and ß-catenin protein accumulation in articular cartilage, and that was further enhanced by combined treatment with rSMSC-EVs and ICA. Conclusion: Our findings highlight the promising potential of using combined treatment with ICA and rSMSC-EVs for promoting osteochondral repair.

Proper use of light environments for mitigating the effects of COVID-19 and other prospective public health emergency lockdowns on sleep quality and fatigue in adolescents.

Coronavirus disease 2019 (COVID-19) remains a public health emergency of international concern, and some countries still implement strict regional lockdowns. Further, the upcoming 2023 Asian Games and World University Games will implement a closed-loop management system. Quarantine can harm mental and physical health, to which adolescents are more vulnerable compared with adults. Previous studies indicated that light can affect our psychology and physiology, and adolescents were exposed to the artificial light environment in the evening during the lockdown. Thus, this study aimed to establish and assess appropriate residential light environments to mitigate the effects of lockdowns on sleep quality and fatigue in adolescents. The participants were 66 adolescents (12.15 ± 2.45 years of age) in a closed-loop management environment, who participated in a 28-day (7-day baseline, 21-day light intervention) randomized controlled trial of a light-emitting diode (LED) light intervention. The adolescents were exposed to different correlated color temperature (CCT) LED light environments (2000 K or 8000 K) for 1 h each evening. The results for self-reported daily sleep quality indicated that the low CCT LED light environment significantly improved sleep quality (p < 0.05), and the blood test results for serum urea and hemoglobin indicated that this environment also significantly reduced fatigue (p < 0.05) and moderately increased performance, compared to the high CCT LED light environment. These findings can serve as a springboard for further research that aims to develop interventions to reduce the effects of public health emergency lockdowns on mental and physical health in adolescents, and provide a reference for participants in the upcoming Asian Games and World University Games.

Room-temperature polariton lasing in GaN microrods with large Rabi splitting.

Room-temperature polariton lasing is achieved in GaN microrods grown by metal-organic vapor phase epitaxy. We demonstrate a large Rabi splitting (Ω = 2g0) up to 162 meV, exceeding the results from both the state-of-the-art nitride-based planar microcavities and previously reported GaN microrods. An ultra-low threshold of 1.8 kW/cm2 is observed by power-dependent photoluminescence spectra, with the linewidth down to 1.31 meV and the blue shift up to 17.8 meV. This large Rabi splitting distinguishes our coherent light emission from a conventional photon lasing, which strongly supports the preparation of coherent light sources in integrated optical circuits and the study of exciting phenomena in macroscopic quantum states.

Analytical models of electron leakage currents in gallium nitride-based laser diodes and light-emitting diodes.

The electrical-to-optical power conversion efficiencies of the light-emitting devices based on gallium nitride (GaN) are seriously limited by electron leakage currents due to the relatively low mobility and activation ratio of holes. However, there have been few theoretical models on the behavior of the leakage current with an increasing total current. We develop an Ohmic-law-like method to describe the transport behaviors of the systems with electron and hole currents simultaneously. Based on reasonable assumptions, the ratio of the leakage current to the total current is related to the differential resistances of the devices. Through the method, we develop analytical models of the leakage currents in GaN-based laser diodes (LDs) and light-emitting diodes (LEDs). The ratios of the leakage currents with total currents in LDs and LEDs are shown to increase, which explains the sublinear behaviors of the luminescence-current (LI) curves of the devices. The theory agrees well with the numerical simulation and experimental results in larger current ranges in comparison to the traditional ABC model. The above analytical model can be used to fast evaluate the leakage currents in GaN-based LDs and LEDs.

Dominant ß-Thalassemia Phenotype Caused by Hb Dieppe (HBB: c.383A>G): Another Case Report.

Homozygous or compound heterozygous mutations of the ß-globin gene lead to ß-thalassemia (ß-thal) major (ß-TM) or ß-thal intermedia (ß-TI), whereas heterozygotes usually show microcytosis with negligible or no hemolysis. Certain missense mutations in exon 3, however, produce unstable globins causing a dominant ß-thal phenotype or hemolytic anemia in heterozygotes. Here we report a mutation in exon 3 of the ß-globin gene, which results in an unstable globin (Hb Dieppe) [ß127(H5)Gln→Arg; HBB: c.383A>G] with a dominant ß-thal phenotype in two generations of a Chinese family. Physicians should be alerted to this mechanism of ß-thal considering its relative rarity.

Two-round quasi-whispering gallery mode exciton polaritons with large Rabi splitting in a GaN microrod.

We investigate the exciton polaritons and their corresponding optical modes in a hexagonal GaN microrod at room temperature. The dispersion curves are measured by the angle-resolved micro-photoluminescence spectrometer, and two types of exciton polaritons are identified with the help of the finite-difference time-domain simulation. By changing the pump position, the photon part of the exciton polaritons is found to switch between the quasi-whispering gallery modes and the two-round quasi-whispering gallery modes. The exciton polaritons formed by the latter are observed and distinguished for the first time, with a giant Rabi splitting as large as 2Ω = 230.3 meV.

Verification and fine mapping of qGW1.05, a major QTL for grain weight in maize (Zea mays L.).

Grain weight, one of the important factors to determine corn yield, is a typical quantitative inheritance trait. However, the molecular genetic basis of grain weight still remains limited. In our previous researches, a major QTL associated with grain weight, qGW1.05, has been identified between SSR markers umc1601 and umc1754 at bin locus 1.05-1.06 in maize. Here, its genetic and environmental stabiliteis were verified using a BC3F2 population to identify the effect of qGW1.05 on grain weight. Further, qGW1.05-NILs were obtained by MAS successfully. Via a large BC6F2 segregation population, together with polymorphic microsatellite markers developed between the parents to screen the genotype of the recombinant plants, qGW1.05 was positioned to a 1.11 Mb genome interval. Furthermore, the progenies of 15 recombinants were tested to confirm the effect of qGW1.05 on grain weight. Combining collinearity among cereal crops and genome annotation, the several candidate genes taking part in grain development were identified in the qGW1.05 region. In this study, qGW1.05 was limited to a 1.11 Mb region on chromosome 1, which established the foundation for understanding the molecular basis underlying kernel development and improving grain weight through MAS using the tightly flanking molecular markers in maize.

Molecular Recognition Properties of Biphen[4]arene.

Biphen[n]arenes (n=3, 4) are a new family of macrocyclic hosts. Here, we describe the molecular recognition behavior of hydroxylated biphen[4]arene (OHBP4) for the first time. A series of cationic guests with different sizes and shapes, including quaternary ammonium salts (1⋅PF6 and 2⋅PF6 ), pyridinium-based guests (3⋅2 PF6 -6⋅2 PF6 ), and cobaltocenium hexafluorophosphate (7⋅PF6 ), were chosen as model guest molecules. OHBP4 exhibits good selectivity towards the 2,7-dibutyldiazapyrenium bis(hexafluorophosphate) (4⋅2 PF6 ) axle to form a [2]pseudorotaxane-type complex. In contrast, hydroxylated biphen[3]arene (OHBP3) cannot bind with this big guest. In addition, OHBP4 strongly interacts with adamantane derivative 2⋅PF6 and cobaltocenium 7⋅PF6 , which have tridimensional shape and relatively large size. The association constant of the 7+ ⊂OHBP4 complex in 1:1 (v/v) [D6 ]acetone/CD2 Cl2 solution is up to 3100±300 m-1 .

Host-guest complexation of pillar[6]arenes towards neutral nitrile guests.

The selective binding behavior of a series of nitrile derivatives by ethylated pillar[6]arene (EtP6A) is described. This work represents the first example of complexation of neutral guests by pillar[6]arenes, although those for pillar[5]arenes have been well documented.

[Case-control study on T-shaped locking internal fixation and external fixation for the treatment of dorsal Barton's fracture].

OBJECTIVE: To compare clinical effect of T-shaped locking internal fixation and external fixation in treating dorsal Barton's fracture,and investigate selective strategy of internal fixation. METHODS: From January 2008 to January 2013, 100 patients with dorsal Barton's fracture were randomly divided into two groups. In treatment group, there were 30 males and 20 females with an average age of (33.8±3.6) years old;30 cases were type B, 20 cases were type C;and treated with T-shaped locking internal fixation. In control group, there were 32 male and 18 females with an average age of (32.9±3.4) years old; 29 cases were type B, 21 cases were type C; and treated with external fixation. Volar tilt, ulnar deviation and radial height at 3 months after operation were detected and compared between two groups. Mechara functional evaluation were used to evaluate postoperative clinical effects. Clinical cure time, postoperative complications,joint mobility and function score were recorded and compared between two groups. RESULTS: In treatment group,volar tilt was (11.9±2.7)°, ulnar deviation was (20.8+ 2.9)°,and radial height was (10.9±1.8) mm; while volar tilt was (9.1±1.6)°, ulnar deviation was (17.1±2.9)°, and radial height was (8.1±1.5) mm in control group. Treatment group was better than control group in volar tilt, ulnar deviation and radial height. Clinical cure time in treatment group was(12.0±2.3) weeks, shorter than control group (18.0±4.1) weeks. The incidence of complications in treatment group was lower than control group. According to Mehara functional evaluation,20 cases got excellent results, 25 good, 3 moderate and 2 poor in treatment group; 16 cases got excellent results, 14 good, 10 moderate and 10 poor in control group. Treatment group was better than control group in clinical effects. CONCLUSION: T-shaped locking internal fixation with postoperative functional exercise for the treatment of dorsal Barton's fracture fits for biomechanics demands,and has advantages of stable fixation,rapid recovery, less complications and good functional recovery, it has better clinical effects.

Biphen[n]arenes.

To design and exploit novel macrocyclic synthetic receptors is a permanent and challenging topic in supramolecular chemistry. Here we describe the one-pot synthesis, unique geometries and intriguing host-guest properties of a new class of supramolecular macrocycles - biphen[n]arenes (n = 3, 4), which are made up of 4,4'-biphenol or 4,4'-biphenol ether units linked by methylene bridges at the 3- and 3'- positions. The biphenarene macrocycles are conveniently accessible/modifiable and extremely guest-friendly. Particularly, biphen[4]arene is capable of forming inclusion complexes with not only organic cationic guests but also neutral π-electron deficient molecules. Compared with calixarenes, resorcinarenes, cyclotriveratrylenes and pillararenes with substituted mono-benzene units, the biphen[n]arenes reported here possess significantly different characteristics in both their topologic structures and their recognition properties, and thus can find broad applications in supramolecular chemistry and other areas.

Silencing Fas-associated phosphatase 1 expression enhances efficiency of chemotherapy for colon carcinoma with oxaliplatin.

AIM: To investigate whether silencing Fas-associated phosphatase 1 (FAP-1) expression enhances the efficiency of chemotherapy for colon carcinoma with oxaliplatin. METHODS: Expression of FAP-1 in mRNA and protein was detected by reverse transcription polymerase chain reaction (RT-PCR) and flow cytometry. Small interfering RNA (siRNA) was designed according to the FAP-1 mRNA sequence. Cell proliferation was evaluated by methyl thiazolyl tetrazolium (MTT) assay. Anenxin V- and propidine iodine (PI) were assayed by flow cytometry for the detection of apoptosis. RESULTS: The expression of FAP-1 was increased in SW480 cells after chemotherapy with oxaliplatin. Transfection of FAP-1 siRNA into SW480 cells silenced the expression of FAP-1 and consequently abolished the inhibitory function of Fas/FasL-mediated apoptosis pathway, thus increasing the efficacy of chemotherapy for colon carcinoma with oxaliplatin. CONCLUSION: RNA interference combined with conventional chemotherapy is more effective against colon cancer.