Proton and molecular permeation through the basal plane of monolayer graphene oxide

Two-dimensional (2D) materials offer a prospect of membranes that combine negligible gas permeability with high proton conductivity and could outperform the existing proton exchange membranes used in various applications including fuel cells. Graphene oxide (GO), a well-known 2D material, facilitates rapid proton transport along its basal plane but proton conductivity across it remains unknown. It is also often presumed that individual GO monolayers contain a large density of nanoscale pinholes that lead to considerable gas leakage across the GO basal plane. Here we show that relatively large, micrometer-scale areas of monolayer GO are impermeable to gases, including helium, while exhibiting proton conductivity through the basal plane which is nearly two orders of magnitude higher than that of graphene. These findings provide insights into the key properties of GO and demonstrate that chemical functionalization of 2D crystals can be utilized to enhance their proton transparency without compromising gas impermeability.

[Exploration of functional reconstruction and rehabilitation strategies for patients with destructive electric burns]

Electric burn is a kind of three-dimensional destructive damage. It is necessary to attach great importance to the functional reconstruction and rehabilitation of patients with destructive electric burns. Wound repair and limb salvage are not the end of the treatment of destructive electric burns, but functional rehabilitation and reintegration into society of patients are the goals of treatment. This paper systematically discusses the early wound repair, late functional reconstruction and rehabilitation, limb salvage and amputation, minimized damage of donor area, psychological rehabilitation, and multi-disciplinary cooperation of destructive electric burns. Only by attaching great importance to the functional reconstruction and rehabilitation, and embedding these concepts in people's brains, perfect repair and rehabilitation of destructive electric burns can be realized.

ScRNA-Seq Reveals a Distinct Osteogenic Progenitor of Alveolar Bone

The metabolism and remodeling of alveolar bone are the most active among the whole skeletal system, which is related to the biological characteristics and heterogeneity of the bone mesenchymal stromal cells (MSCs). However, there is a lack of systematic description of the heterogeneity of MSC-derived osteoblastic lineage cells as well as their distinct osteogenic differentiation trajectory of alveolar bone. In this study, we constructed a single-cell atlas of the mouse alveolar bone cells through single-cell RNA sequencing (scRNA-seq). Remarkably, by comparing the cell compositions between the alveolar bone and long bone, we uncovered a previously undescribed cell population that exhibits a high expression of protocadherin Fat4 (Fat4⁺ cells) and is specifically enriched around alveolar bone marrow cavities. ScRNA-seq analysis indicated that Fat4⁺ cells may initiate a distinct osteogenic differentiation trajectory in the alveolar bone. By isolating and cultivating Fat4⁺ cells in vitro, we demonstrated that they possess colony-forming, osteogenic, and adipogenic capabilities. Moreover, FAT4 knockdown could significantly inhibit the osteogenic differentiation of alveolar bone MSCs. Furthermore, we revealed that the Fat4⁺ cells exhibit a core transcriptional signature consisting of several key transcription factors, such as SOX6, which are involved in osteogenesis, and further demonstrated that SOX6 is required for the efficient osteogenic differentiation of the Fat4⁺ cells. Collectively, our high-resolution single-cell atlas of the alveolar bone reveals a distinct osteogenic progenitor that may contribute to the unique physiological characteristics of alveolar bone.

Oct4 reduction contributes to testicular injury of unilateral testicular torsion in mice model and apoptotic death of Sertoli cells through mediating CIP2A expression

This study explored the mechanism of ipsilateral testis injury after ipsilateral testicular torsion detorsion (T/D) and the potential testis-protective part of the octamer-binding transcription factor 4 (Oct4)-cancerous inhibitors of protein phosphatase 2A (CIP2A) axis in a T/D animal model and in ischemia-reperfusion (IR)-treated testicular Sertoli TM4 cells. Quantitative Polymerase chain reaction (PCR) and western blot (WB) confirmed the downregulation of both CIP2A and Oct4 expression in the testicular tissue from T/D mice compared with sham-operated mice. T/D model was then established in mice with upregulated Oct4 expression in the testis. Oct4 elevation restored CIP2A expression in testes after T/D treatment. Furthermore, we observed that an increase in Oct4 ameliorated the testicular damage caused by torsion in the testis. Biochemical analysis indicated that T/D treatment increased serum anti-sperm antibody levels, but reduced testosterone levels. Meanwhile, in testicular tissue, reactive oxygen species (ROS), malondialdehyde (MDA), and activity of testicular myeloperoxidase (MPO) enzymes were promoted, while glutathione peroxidase activity (GPx) was decreased by T/D injury. Notably, testicular Oct4 restoration partially counteracted the effect of T/D treatment on these biochemical indices. Hypoxia/reoxygenation (HR) treatment was applied to TM4 cells to mimic TT injury in vitro. A gain-of-function study showed that Oct4 overexpression partly counteracted the promoting role of HR in cell damage, apoptosis, and oxidative stress in TM4 cells. These observations provide novel insights into the possible biochemical mechanism underlying the mediation of the Oct4-CIP2A axis in T/D injury.

Osteoblastic RAR Inhibition Causes VAD-Like Craniofacial Skeletal Deformity

Retinoid signaling disorders cause craniofacial deformity, among which infants with maternal vitamin A deficiency (VAD) exhibited malformation of the eye, nose, palate, and parietal and jaw bone. Previous research uncovered the pathogenesis of eye defect and cleft palate of VAD in mice, but the studies on craniofacial skeletal deformity met obstacles, and the cell/lineage and underlying mechanism remain unclear. The retinoic acid receptor (RAR) is the key transcription factor in retinoid signaling, but individual knockout cannot simulate pathway inhibition. Here, we conditionally expressed dominant-negative RARα mutation (dnRARα) in osteoblasts to specifically inhibit the transcription activity of RAR in mice, which mimics the craniofacial deformities caused by VAD in clinical cases: hypomineralization of cranial bones, mandibular deformity, and clavicular hypoplasia. Furthermore, we performed 3-dimensional reconstruction based on micro-computed tomography and confirmed the abnormalities in the shape, size, and ossification of craniofacial bones due to osteoblastic RAR inhibition. Histological analysis indicated that inhibition of RAR in osteoblasts impaired both bone formation and bone resorption, which was confirmed by transcriptome sequencing of the calvaria. Furthermore, mechanism investigation showed that inhibition of RAR in osteoblasts directly decreased osteoblast differentiation in a cell-autonomous manner by impairing osteogenic gene transcription and also inhibited osteoclast differentiation via osteoblast-osteoclast crosstalk by impairing Rankl transcription. In summary, osteoblastic RAR activity is critical to craniofacial skeletal development, and its dysfunction leads to skeletal deformities mimicking VAD craniofacial defects, providing a new insight for VAD pathogenesis.

Accounting for the High Enrollment of African Americans on Winship Cancer Institute's Myeloma Clinical Trials

Background

Thirty-four percent of Multiple Myeloma (MM) clinical trial participants at Winship Cancer Institute (Winship) are African American (AA); however, AAs make up only 4.5 percent of myeloma clinical trial participants in the United States. Given our high enrollment, we aimed to measure AAs' trust in providers and identify if clinical trial enrollment barriers exist.

Methodology

A member of the ethics research team surveyed AA patients who had consented to a MM clinical trial at Winship. Three validated surveys were used: Trust in Medical Research (TMR); Human Connection (THC) which measures how much patients feel they are heard and valued by their physicians; and the Duke Intrinsic Religiosity Scale (DUREL) which measures strength of religious engagement and belief. The survey also included questions about the impact of side effects, distance to the trial center and trial related costs on the decision to participate in clinical trial.

Results

Ninety-two percent (61/67) of patients approached consented. The mean TMR score and the mean THC score were significantly higher (P-value < 0.001) than the results obtained in key national surveys (TMR 14.9 compared to 11.65; THC 57.7 compared to 54.6). These two surveys were significantly correlated, meaning trust and human connection increase or decrease in tandem. The 3 religiosity subscale results showed high religiosity (3.84, 4.36, and 4.35 with 5 being the highest score). The mean scores of the importance of the investigational agent's side effects, trial costs, and distance to trial center on the decision to enroll in a clinical trial were also high (8.5, 7.8, and 6.5, respectively, with 10 being the most important).

Conclusion

In our study population, high trust and human connection overcame other trial participation barriers: strong religious beliefs and concerns about side effects, costs, and travel distance. We present a roadmap to guide investigators to increase human connection, and hopefully trust.

Salvage endoscopic surgery for skull base osteoradionecrosis in nasopharyngeal carcinoma patients: A prospective, observational, single-arm clinical study

BACKGROUND

Postradiation skull base osteoradionecrosis (ORN) is a severe complication that occurs after radiotherapy in patients with nasopharyngeal carcinoma (NPC) that can severely affect quality of life (QOL) and be life threatening. Only 13.4% - 28.6% of patients can be cured by traditional repeated endoscopic debridement. Here, we introduced salvage endoscopic surgery for skull base ORN patients and evaluated its clinical efficacy.

METHODS

This was a prospective, observational, single-arm clinical study. Clinical data from 18 skull base ORN patients who underwent radical endoscopic necrectomy followed by reconstruction using a septal pedicled mucosal flap or temporal muscle flap were included in the study. The endpoint was an overall survival (OS) of 2 years. The numeric rating scale (NRS) scores for pain and foul odor were analyzed to determine the efficacy and safety of this surgery.

RESULTS

A total of 21 patients were recruited, 18 of whom completed the study and were analyzed. All surgeries were successfully performed. During the 2-year study, the OS rate of the entire cohort was 75%. The median NRS score for pain decreased from 6.44 +- 2.62 to 0.50 +- 0.71, and the NRS score for foul odor decreased from 1.89±1.08 to 1 after surgery.

CONCLUSIONS

Salvage endoscopic necrectomy followed by construction using a septal pedicled mucosal flap or temporal muscle flap is a novel, safe, and effective treatment for ORN in patients with NPC.

CLINICAL TRIAL REGISTRATION

This study was approved by the independent ethics committee of the Eye, Ear, Nose and Throat Hospital of Fudan University (IEC No. 2019095-1). Written informed consent was obtained from all patients. The study was registered with the Chinese Clinical Trial registry (ChiCTR2000029327).

Association of Circulating Caprylic Acid with Risk of Mild Cognitive Impairment and Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative (ADNI) Cohort

OBJECTIVE

Medium-chain fatty acids (MCFAs) can rapidly cross the blood-brain barrier and provide an alternative energy source for the brain. This study aims to determine 1) whether plasma caprylic acid (C8:0) is associated with risk of incident mild cognitive impairment (MCI) among baseline cognitively normal (CN) participants, and incident Alzheimer's Disease (AD) among baseline MCI participants; and 2) whether these associations differ by sex, comorbidity of cardiometabolic diseases, apolipoprotein E (APOE) ε4 alleles, and ADAS-Cog 13.

METHODS

Within the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort, plasma C8:0 was measured at baseline in 618 AD-free participants aged 55 to 91. Logistic regression models were used to estimate odds ratios (ORs) and 95% CIs with incident MCI and AD as dependent variables, separately.

RESULTS

The inverse association between circulating C8:0 and risk of incident MCI was of borderline significance. The inverse association between circulating levels of C8:0 and risk of incident MCI was significant among CN participants with ≥1 cardiometabolic diseases [OR (95% CI): 0.75 (0.58-0.98) (P=0.03)], those with one copy of APOE ε4 alleles [OR (95% CI): 0.43 (0.21-0.89) (P=0.02)], female [OR (95% CI): 0.60 (0.38-0.94) (P=0.02)], and ADAS-Cog 13 above the median [OR (95%CI): 0.69 (0.50-0.97)(P=0.03)] after adjusting for all covariates.

CONCLUSION

The inverse associations were present only among subgroups of CN participants, including female individuals, those with one or more cardiometabolic diseases, or one APOE ε4 allele, or higher ADAS-Cog 13 scores. If confirmed, this finding will facilitate precision prevention of MCI, in turn, AD among CN older adults.

Renewable Vanillin-Based Thermoplastic Polybutadiene Rubber: High Strength, Recyclability, Self-Welding, Shape Memory, and Antibacterial Properties

The vast majority of traditional vulcanized rubber products are insoluble and infusible, which is difficult to reprocess and biodegrade, resulting in black pollution. In addition, although most rubber materials based on covalent adaptive networks (CANs) can achieve structural reconstruction, the lack of traditional vulcanization system leads to a decline in strength. In this study, biobased vanillin derivatives (PV) were synthesized to cross-link the commercially available 1,2-polybutadiene rubber precursor to construct imine-based CANs, thereby fabricating a resource-renewable, recyclable, and degradable high-performance rubber material. Due to the rigid tripod structure of the PV, the tensile strength of the material can achieve as high as 16.24 MPa, ranking among the best in the field of recyclable polybutadiene-based materials. Benefiting from the dynamic imine unit, the "dynamic covalent bridge" can be re-established to repair the damaged network and endow the material with excellent weldability. And, shape memory faculty of the material was proved and depicted. Moreover, this material displayed excellent antibacterial property originates from the introduced Schiff-base structure. By mixing with graphene, the application of action sensors can also be achieved.

Self-Strengthening, Self-Welding, Shape Memory, and Recyclable Polybutadiene-Based Material Driven by Dual-Dynamic Units

A covalent adaptable network can endow rubber materials with recyclability and reprocessability and is expected to alleviate black pollution caused by end-of-life rubber. However, the loss of traditional vulcanization systems severely sacrifices their strength, and the tensile strength in the current study rarely exceeds 10 MPa unless fillers are added. In this work, we proposed a self-strengthening process based on dual-dynamic units (imine and disulfide), briefly, under heating, phenylsulfur radicals generated from aromatic disulfide bonds can react with double bonds (mostly vinyl) and/or couple with allyl sites, thus reforming a stronger cross-linked network. The neighboring imine unit is not affected and provides excellent thermal reprocessability and chemical recyclability. The result shows that the tensile strength can reach 19.27 MPa via self-strengthening without adding fillers or any other additives, and this ultra-high-strength is much higher than those of all known recyclable polybutadiene-based rubber materials. In addition, the material also has malleability, shape memory, and self-welding properties. By doping carbon nanotubes, a recyclable conductive composite can also be achieved. In general, we envision that this enhanced strategy has great potential to be generalized for all elastomers containing double bonds (such as styrene-butadiene rubber, nitrile rubber, isoprene rubber, and their derivatives). The reprocessability and self-welding are practical for on-site assembly or repair of composite parts and extend the service life of materials.

Thermally stable vanadium complexes supported by the iminophenyl oxazolinylphenylamine ligands: synthesis, characterization and application for ethylene (co-)polymerization

In this work, a series of oxovanadium complexes bearing the ligands (S,E)-(+)-2, 6-dialkyl-N-(2-((2-(4-isopropyl-4,5-dihydrooxazole-2-yl)phenyl)amino)benzylidene)aniline (dialkyl = dimethyl (V1), diethyl (V2), and isopropyl (V3)) have been synthesized and characterized by FTIR spectroscopy and elemental analysis. Moreover, the molecular structures of complexes V2 and V3 were defined by X-ray diffraction. On activation with ethylaluminium sesquichloride (Al₂Et₃Cl₃), these complexes exhibited high activity towards ethylene polymerization (up to 1.39 × 10⁷ g mol_v^-1 h^-1) and showed excellent thermal stability (up to 60 °C). The obtained polyethylene had a moderate molecular weight (21.9 × 10⁴ to 66.4 × 10⁴ g mol^-1) and exhibited narrow distribution (1.91 to 2.86) and unimodal features. The effect of the substituents on the ligands was also investigated in detail. The compound bearing the diisopropyl group showed the highest activity toward ethylene polymerization as the bimolecular deactivation of the catalyst can be effectively inhibited by the steric hindrance of the ortho-substituent on aniline. The complex V2 with moderate steric hindrance was also evaluated as a catalyst for the copolymerization of ethylene with norbornene and showed moderate to high activity.

Clinical phenotypes of cardiac sarcoidosis by latent class analysis

Background

Sarcoidosis is a systemic granulomatous disease with cardiac involvement reported in 20–27% of patients [1]. Cardiac sarcoidosis (CS) can lead to atrial or ventricular arrhythmias, various conduction system disorders, heart failure or sudden cardiac death, depending on the location of myocardial involvement [2]. Previous studies have investigated the possible types of CS based on the distribution of myocardial involvement on imaging as well as the role of genetic factors [3,4]. However, there are no studies describing the clinical heterogeneity of CS patients.

Purpose

In order to determine if clinical clusters exist in CS, we carried out a latent class analysis (LCA) to explore potential phenotypes in a large sample of CS patients from the National Inpatient Sample (NIS).

Methods

We identified 848 patients with a diagnosis of CS from the NIS in 2016–2018. A LCA was performed based on comorbidities. Utilizing the Bayesian information criterion and Akaike's information criterion we divided our study population into 3 cohorts. We subsequently applied the LCA model for our study population to fit each patient into one of the 3 cohorts. Finally, we compared the clinical outcomes among the 3 groups.

Results

Following LCA, patients in cohort 3 were strongly associated with a cardiometabolic syndrome profile with the highest prevalence of congestive heart failure (CHF, 95.1%), chronic kidney disease (CKD, 69.7%), diabetes mellitus (68.9%), hyperlipidemia (52.5%) and obesity (45.1%). Patients in cohort 2 had an intermediate prevalence of cardiometabolic syndrome with a universal diagnosis of hypertension (100%) but with the lowest number of CHF (32.5%) patients and none with CKD. Finally, patients in cohort 1 had the least comorbidities in comparison to the other groups but there was a higher prevalence of CHF (71.7%). There was no significant difference in mortality among the 3 groups, but acute respiratory failure was the highest in cohort 3. However, ventricular arrhythmias were more prevalent in cohort 1 patients (Table).

Conclusion

We identified 3 different types of CS based on their clinical phenotype. The clinical outcomes varied among the cohorts with ventricular arrhythmias being the most prevalent in patients with the least cardiometabolic comorbidities.

Funding Acknowledgement

Type of funding sources: None.

Catalyst-Free Vitrimer Cross-Linked by Biomass-Derived Compounds with Mechanical Robustness, Reprocessability, and Multishape Memory Effects

Vitrimerization of thermoset polymers plays an important role in addressing resource recovery and reuse. Vitrimer elastomers with good mechanical properties often require well-designed crosslinking agents or fillers, but this increases processing complexity or reduces vitrimer dynamic properties. In this report, a simple green strategy to build a strong vitrimer elastomer is designed. Commercially available epoxidized natural rubber (ENR) is cross-linked with biomass-derived D-Fructose 1,6-bisphosphoric acid to get a vitrimer elastomer cross-linked by β-hydroxy phosphate ester bonds and has abundant hydrogen bonds. Hydrogen bonds can preferentially break and dissipate energy under external forces, which makes the sample robust. The topological network can be reformed at high temperatures through the dynamic exchange of β-hydroxy phosphate ester bonds, which gives the material malleability and recyclability. In addition, through the strategy of combining reprocessing and welding, multiple shape memory effects can be achieved in one postprocessing step. Considering that a variety of commercially available epoxy polymers are easily available, it is believed that this strategy can be a simple and versatile way to enable commercial epoxy polymers to achieve green crosslinking through biomass crosslink agents, which results in robust and recyclable vitrimers based on β-hydroxy phosphate bonds.

Smoking and incidence of insomnia: a systematic review and meta-analysis of cohort studies

OBJECTIVE

This study investigated the impact of smoking on the incidence of insomnia.

STUDY DESIGN

Systematic review and meta-analysis of cohort studies.

METHODS

PubMed, EMBASE, Web of Science, Cochrane Library, and OVID were searched through March 2020. Cohort studies reporting the effect of smoking on the incidence of insomnia were included. We quantitatively analyzed the basic framework and study characteristics and then pooled estimate effects with 95% confidence intervals (CIs) of outcomes of each included study using fixed-effects meta-analyses.

RESULTS

This systematic review included six cohort studies involving 12,445 participants. Quantitatively summarized results suggested that smoking could significantly increase the incidence of insomnia (odds ratio [OR]: 1.07, 95% CI: 1.02, 1.13). Regular smoking was significantly associated with the incidence of insomnia (OR = 1.07, 95% CI: 1.01, 1.13). As for occasional smokers and ex-smokers, the pooled analysis did not indicate a significant association (occasional smoker: OR = 2.09, 95% CI: 0.44, 9.95; ex-smoker; OR = 1.02, 95% CI: 0.67, 1.54). Subgroup analysis by age, gender ratio, and region showed a statistically significant relationship between smoking and the incidence of insomnia in specific groups.

CONCLUSIONS

Integrated longitudinal observational evidence identified smoking as a significant risk factor of insomnia. Considering the limited amount of available studies, more high-quality and prospective cohort studies of large sample sizes are needed to explore details of this association.

The association between the vaginal microenvironment and fecundability: a register-based cohort study among Chinese women

OBJECTIVE

To evaluate the association between the vaginal microenvironment and fecundability among women.

DESIGN

Register-based nationwide cohort study.

SETTING

Chinese National Free Pre-conception Check-up Project from 2015 to 2018.

POPULATION

Our study included a total of 3 388 554 eligible women who were attempting to become pregnant.

METHOD

We assessed the vaginal microenvironment at baseline by considering four indices: vaginal pH, clue cell examination, whiff test and vaginal cleanliness grading. If any of these indicators was abnormal, the vaginal microenvironment was defined as poor. Propensity score matching was used to control for potential confounders and reduce bias. Logistic models were used to estimate the fecundability odds ratios (FORs) after adjustment for covariates.

MAIN OUTCOME MEASURES

Achievement of a pregnancy within 1 year.

RESULTS

Of the total study population, 379 718 women (11.2%) had a poor vaginal microenvironment and their pregnancy rate after 1 year was significantly lower than the group with a normal microenvironment (71.8% versus 76.1%, P < 0.001). After adjusting for potential confounders, the women with a poor vaginal microenvironment were associated with a 9% reduction in fecundability compared with the normal microenvironment group (FOR 0.91, 95% CI 0.90-0.92). The adverse effects of a poor vaginal microenvironment were stronger among multipara (FOR 0.89, 95% CI 0.87-0.90) or women with irregular menstruation (FOR 0.86, 95% CI 0.84-0.89).

CONCLUSION

There was a negative association between a poor vaginal microenvironment and the fecundability of women. These findings highlight the significance of assessing the vaginal microenvironment during pre-pregnancy health examinations.

TWEETABLE ABSTRACT

Women with a poor vaginal microenvironment were associated with a reduction in fecundability.

An In-Situ Self-regeneration Catalyst for the Production of Renewable Penta-1,3-diene

Catalyst deactivation is a problem of great concern for many heterogeneous reactions. Here, an urchin-like LaPO₄ catalyst was easily developed for pentane-2,3-diol dehydration; it has an impressive ability to restore the activity in situ by itself during the reaction, accounting for its high stability. This facilitates the efficient production of renewable penta-1,3-diene from pentane-2,3-dione via a novel approach, where penta-2,3-diol was obtained as an intermediate in 95 % yield under mild conditions.

FOXO3 Mediates Tooth Movement by Regulating Force-Induced Osteogenesis

The high prevalence of malocclusion and dentofacial malformations means that the demand for orthodontic treatments has been increasing rapidly. As the biological basis of orthodontic treatment, the mechanism of mechanical force-induced alveolar bone remodeling during orthodontic tooth movement (OTM) has become the key scientific issue of orthodontics. It has been demonstrated that bone mesenchymal stem cells (BMSCs) are crucial for bone remodeling and exhibit mechanical sensing properties. Mechanical force can promote osteoblastic differentiation of BMSCs and osteogenesis, but the key factor that mediates mechanical force-induced osteogenesis during OTM remains unclear. In this study, by performing reverse-phase protein arrays on BMSCs exposed to mechanical force, we found that the expression level of forkhead box O3 (FOXO3) was significantly upregulated during the mechanical force-induced osteoblastic differentiation of BMSCs. The number of FOXO3-positive cells was consistently higher on the OTM side as compared with the control side and accompanied by the enhancement of osteogenesis. Remarkably, inhibiting FOXO3 with repaglinide delayed OTM by severely impairing mechanical force-induced bone formation in vivo. Moreover, knockdown of FOXO3 effectively inhibited the mechanical force-induced osteoblastic differentiation of BMSCs, whereas the overexpression of FOXO3 enhanced this effect. Mechanistically, we revealed a novel regulatory model in which FOXO3 promoted osteocalcin transcription by activating its promoter in cooperation with runt-related transcription factor 2 (RUNX2). We collectively obtained the first evidence that FOXO3 is critical for OTM, where it responds to mechanical force and directly regulates downstream osteoblastic differentiation in an efficient manner.

MiR-802 inhibits the malignant biological behavior of oral squamous cell carcinoma by targeting proto-oncogene MET

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is one of the frequently occurring malignancies, but effective treatments are lacking. It is believed that exploring new molecular targets could help us to improve the treatment of OSCC. Therefore, we hope to find a new miRNA target to control OSCC.

PATIENTS AND METHODS

qPCR and Western blots were used to test the expressions of miR-802 and target gene in OSCC tissues and cell lines. Luciferase reporter assay was performed to check whether miR-802 could directly target MET. CCK-8, wound healing, cell invasion, colony formation, and tumor growth assays were used to determine the functions of miR-802 and MET in the malignant biological behavior of OSCC.

RESULTS

The results suggested that miR-802 was low expressed in OSCC tissues and cell lines. Overexpression of miR-802 inhibited the cell viability, colony formation, migration and invasion of Tca8113 and SCC9 cells, and tumor growth in vivo. It was predicted that miR-802 might target the mRNA of proto-oncogene MET. Overexpressing miR-802 suppressed the expression of wild-type MET at both protein and mRNA levels in Tca8113 and SCC9 cells. Moreover, the expression of MET was high and significantly correlated with the low expression of miR-802 in OSCC tissues. Overexpression of MET in Tca8113 and SCC9 cells reduced the tumor-suppressive effects, which was induced by miR-802 overexpression.

CONCLUSIONS

MiR-802 suppresses the malignant biological behavior of OSCC by targeting proto-oncogene MET. This work provides a new potential molecular target for treating OSCC.

Assembling of Reprocessable Polybutadiene-Based Vitrimers with High Strength and Shape Memory via Catalyst-Free Imine-Coordinated Boroxine

Vitrimers endow cross-linked polymers with malleability and reprocessability via exchange reactions. However, designing of reprocessable, shape-memory polymer materials with high strength via a catalyst-free method remains a challenge under mild conditions. Here, we propose a facile strategy to address this dilemma by introducing the exchangeable imine bond and N-coordinated boroxine into a polybutadiene (PB)-based network. Specifically, PB grafted with 2-aminoethanethiol is reacted with the formyl group of phenylboronic acid and dehydrated to form a dual-dynamic covalently cross-linked network at room temperature. The dynamic network draws on the advantage of imine (toughness) and N-coordinated boroxine (strength), making the PB-based materials exhibit favorable malleability, mechanical property, reprocessability, and thermal-induced shape-memory behavior. We can obtain customized high mechanical properties by tuning the cross-linking density, and the tensile strength reaches a high value (12.35 MPa) without fillers or any other additives. Meanwhile, the unique network framework makes the material recycle over several times without sacrificing its property. This work presents a facile and effective approach to achieve a multifunctional polymer with customized attributes. Besides, this strategy can recycle end-of-life rubber to alleviate environmental pollution and provide inspiration for fabricating targeted materials by uniting the dynamic covalent or noncovalent bonds.

Fabrication of boron nitride nanosheet/polymer composites with tunable thermal insulating properties

Introduction of hydroxylated hBN improved the thermal insulation performance in binary composites, but enhanced the thermal conductivities in the ternary formula.

Selectively creating oxygen vacancies on PrCe/SiO2 catalysts for the transformation of a furfural–acetone adduct into a functionalized 1,3-diene

Oxygen vacancies were selectively created on PrCe/SiO₂ for efficient transformation of a furfural–acetone adduct into a functionalized 1,3-diene.

Puerarin Stimulates Osteogenic Differentiation and Bone Formation Through the ERK1/2 and p38-MAPK Signaling Pathways

BACKGROUND

Osteoporosis is a world-wide health problem, which leads to decreased bone strength and increased susceptibility to fractures. Puerarin, a phytoestrogen extracted from Pueraria lobata (Willd.) Ohwi, has been identified as a promising intervention for preventing bone loss and promoting bone regeneration. However, the underlying mechanisms for its anabolic action are still not clear. In the present study, we aimed to investigate the effect of puerarin on the osteogenic differentiation of bone marrow stromal cells (BMSCs) and the possible molecular mechanism mediating its action.

METHODS

Bone marrow stromal cells (BMSCs) and intragastric administration on ovariectomized(OVX) rats were used to study the anti-osteoporotic function of puerarin. The involvement of mitogen-activated protein kinase (MAPK) signaling pathways was determined.

RESULTS

Our results demonstrated that at optimal concentration, puerarin could promote osteogenic differentiation of BMSCs in vitro. This induction was mediated by MAPK signaling pathway. Further detailed study revealed that ERK1/2-Runx2 signaling pathway had more prominent effect than p38 signaling pathway in puerarin-induced differentiation of BMSCs toward the osteogenic phenotype. We also found that puerarin protected against reduction in bone mineral density and improved femur trabecular bone structure in ovariectomized rats.

CONCLUSION

Our findings revealed the functional mechanism of puerarin in promoting osteogenic differentiation which involved ERK1/2 and p38-MAPK pathway and provided experimental evidence for the potential application of puerarin for estrogen replacement therapy of osteoporosis.

Facile synthesis of hierarchically porous carbonaceous materials derived from olefin/aldehyde precursors using silica as templates

Porous carbon is exceptionally useful, but it remains a great challenge to develop a facile route to prepare porous carbon materials with hierarchical structure and enhanced porosity. This work demonstrates a novel synthetic pathway for hierarchical carbonaceous materials (HCM) using isobutene and formaldehyde as carbon precursors via silica templates impregnated with phosphorus. Different from the traditional nanocasting method, the formation of the carbon structure is caused by heavy coke deposits on the solid catalyst in the course of the olefin/aldehyde vapor reaction. The coke-derived carbonaceous materials indicated by transmission electron microscopy (TEM) and nitrogen adsorption–desorption measurement are hierarchically mesoporous structures with a large surface area (971 m² g⁻¹) and pore volume (1.91 cm³ g⁻¹). We have demonstrated for the first time that the olefin/aldehyde reaction may provide a convenient route to develop a porous carbon texture. The newly developed method may lead to porous carbon having scientific and technological importance in adsorption and catalysis applications.

This work presents a novel procedure to synthesize hierarchically porous carbonaceous materials by coke formation.

Decreased Expression of MYPT1 Contributes to Tumor Angiogenesis and Poor Patient Prognosis in Human Prostate Cancer

BACKGROUND

Our previous study demonstrated that Myosin Phosphatase Targeting subunit 1 (MYPT1) may function as a direct target of microRNA-30d, which promotes tumor angiogenesis and tumor growth of prostate cancer (PCa). Here, we aimed to investigate the clinical significance of MYPT1 expression and its functions in PCa.

METHODS

Roles of MYPT1 deregulation in tumor angiogenesis of PCa was determined in vitro and in vivo experiments. Expression patterns of MYPT1 and CD31 proteins were examined by immunohistochemistry and immunofluorescence, respectively. Associations of MYPT1/CD31 combination with various clinicopathological features and patients' prognosis of PCa were also statistically evaluated.

RESULTS

Through gain- and loss-of-function experiments, MYPT1 inhibited capillary tube formation of endothelial cells and in vivo tumor angiogenesis in a mouse model with the downregulation of VEGF and CD31 expression. In addition, MYPT1 expression was significantly decreased, while CD31 expression was dramatically increased in PCa tissues compared to benign prostate tissues. Notably, MYPT1 expression levels in PCa tissues were negatively correlated with that of CD31. Statistically, MYPT1-low/CD31- high expression was distinctly associated with high Gleason score, positive biochemical recurrence, and reduced overall survival of PCa patients. Moreover, PCa patients with MYPT1-low/CD31-high expression more frequently had shorter overall, biochemical recurrence-free and metastasis-free survivals. MYPT1/CD31 combination was identified as an independent factor to predict biochemical recurrence-free and metastasis-free survivals of PCa patients.

CONCLUSIONS

Our findings indicate that MYPT1 may inhibit angiogenesis and contribute favorable prognosis in PCa patients, implying that MYPT1 might be a potential drug candidate in anticancer therapy.

Rewarding Network Mechanism of Left Orbito-frontal Cortex Transcranial Magnetic Stimulation in Depression

Objective

The difficulties in the clinical antidepressant treatment lead to the pursuing of more effective methods such as transcranial magnetic stimulation (TMS). Mixed findings from DLPFC targeted TMS result in the exploration of optimal stimulation location. Disturbed function of obitofrontal cortex (OFC) has been indicated in depression, which is involving in the remission of depression. However, whether it could be a more specific treating target is not tested. Simultaneously, disturbed reward network (RN) has been confirmed in depression, however, whether this could be improved by TMS treatment remains unclear.

Methods

Fourteen patients with major depressive disorder (MDD) were allocated in a four-week course of OFC targeted TMS. Motivated by the literature, before and after the treatment, the function connectivity of RN with the seed of ventral striatum was conducted. The results were also compared with the data from 33 healthy controls.

Results

The OFC targeted TMS improved the clinical depression significantly and enhanced the function connectivity within the RN effectively. Specifically, lower baseline dorsolateral striatum connectivity predicted strong therapeutic effect of TMS on depression, while lower baseline insula connectivity predicted weak therapeutic effect on depression.

Conclusions

The findings offer the first experimental evidence of the therapeutic effect of OFC targeted TMS on clinical depression, enhanced function connectivity within RN might be the potential neural mechanism (Fig. 1). Lower dorsolateral striatum connection might be a reliable neural biomarker of strong responding for TMS treatment, which helps to identify the patients who will be cured by TMS most effectively.

Assembly line synthesis of isoprene from formaldehyde and isobutene over SiO2-supported MoP catalysts with active deposited carbon

Isoprene was synthesized over MoP catalysts with active carbonaceous deposits in an “assembly line” process.

The alienation of affection toward parents and influential factors in Chinese left-behind children

OBJECTIVE

Although alienation toward parents is important for children (for current mental health status or later interpersonal relationships in adulthood), it is undervalued and even lacks a standardized tool of assessment. Moreover, the large number of left-behind children in China is a cause of public concern. However, their experienced alienation toward their parents remains unclear, which may be important for early detection or intervention for behavioral problems in this population. Hence, the current study aimed to develop an alienation inventory for children and then use it to investigate the experienced alienation toward parents in Chinese left-behind children.

METHODS

Two studies were carried out. Study 1 was designed to develop a standard inventory of alienation toward parents (IAP). In study 2, 8361 children and adolescents (6704 of them were left-behind status) of the Chongqing area, aged between 8 and 19 years old, were recruited for investigation. All participants were surveyed with a standard sociodemographic questionnaire, children's cognitive style questionnaire, children's depression inventory, adolescent self-rating life events checklist, and newly built IAP in study 1.

RESULTS

In study 1, we developed a two-component (communication and emotional distance) and 18-item (9 items for maternal or paternal form, respectively) IAP questionnaire. In study 2, exploratory factor analysis indicated an expected two-factor structure of IAP, which was confirmed by confirmatory factor analysis. The Cronbach's alpha coefficients showed a good reliability (0.887 and 0.821 for maternal and paternal form, respectively). Children with absent mother experienced the highest alienation toward parents. Boys as well as children aged 8-10 years old experienced higher alienation toward parents. Poor communication with parents (sparse or no connection), level of left-behind condition (parents divorced, been far away from parents), and psychosocial vulnerability (stressful life events, negative cognitive style) were risk factors of alienation toward parents.

CONCLUSIONS

The current study develops a two-factor (communication and emotional distance) IAP, which offers a reliable tool to assess experienced alienation of affection toward parents in children aged between 8 and 19 years old. Our result is the first investigation of experienced alienation and potential influential factors in Chinese left-behind children. The findings that children with absent mother experience higher alienation toward parents, as well as three recognized risk factors for alienation of affection toward parents (poor communication with absent parents, worse left-behind condition, and psychosocial vulnerability), give valuable guidance for parents who intend to leave or who are already leaving as well as for government policymaking.

Mechanical Strain Promotes Osteogenesis of BMSCs from Ovariectomized Rats via the ERK1/2 but not p38 or JNK-MAPK Signaling Pathways

Osteoporosis has become a world-wide health problem. As a promising intervention, mechanical strain is considered to be an important factor in bone remodeling. However, the underlying mechanisms are still not clarified clearly. In the present study, we aim to investigate the possible mechanism by which mechanical stimulation induces osteogenic differentiation of bone mesenchymal stem cells (BMSCs) from ovariectomized rats (OVX BMSCs). The results demonstrated that intermittent mechanical strain (IMS) promoted osteogenic differentiation of OVX BMSCs by activating Runt-related transcription factor 2 (Runx2). When the extracellular regulated kinase1/2-mitogen activated protein kinases (ERK1/2-MAPK) signaling pathway was blocked, the osteogenenic effects of IMS were diminished; while blocking of the p38-MAPK signaling pathway had little effect on subsequent osteogenic events. In addition, the phosphorylation level of JNK was not affected by IMS. Our results indicated that strain-induced osteogenic differentiation of OVX BMSCs may take effect via ERK1/2-MAPK not p38 or c-Jun N-terminal (JNK)-MAPK signaling pathway. These findings may have implications for physical treatment of osteoporosis in vitro.

Toxicity study of ochratoxin A using HEK293 and HepG2 cell lines based on microRNA profiling

Ochratoxin A (OTA) induced DNA damage, cytotoxicity, and apoptosis in mammalian cell lines. Micro RNAs (miRNAs) are involved in physiological and developmental processes and contribute to cancer development and progression. In our study, high-throughput miRNA profiling and Kyoto Encyclopedia of Genes and Genomes analysis were applied to comparatively study the toxicity of OTA in HEK293 cells and HepG2 cells treated with 25 μM OTA for 24 h. In these two cells, the same changing miRNAs were mostly related to signal transduction pathways, whereas the different changing miRNAs were mostly related to human cancer pathways. DGCR8, Dicer1, and Drosha were significantly suppressed in HEK293 cells, indicating an impairment of miRNA biogenesis. The damage seemed more extensive in HEK293 cells. Cell models and in vivo models were also compared. Many miRNAs in vitro were markedly different from those in vivo; however, OTA toxicity was observed both in vitro and in vivo. The classification of deregulated pathways is similar. The biogenesis of miRNA was impaired in both lines. In conclusion, deregulated miRNAs in vitro are mostly related to human cancer and signal transduction pathways. The deregulated pathways in vivo are similar to those in vitro.

Bone marrow cells differentiation into organ cells using stem cell therapy

Bone marrow cells (BMC) are progenitors of bone, cartilage, skeletal tissue, the hematopoiesis-supporting stroma and adipocyte cells. BMCs have the potential to differentiate into neural cells, cardiac myocytes, liver hepatocytes, chondrocytes, renal, corneal, blood, and myogenic cells. The bone marrow cell cultures from stromal and mesenchymal cells are called multipotent adult progenitor cells (MAPCs). MAPCs can differentiate into mesenchymal cells, visceral mesoderm, neuroectoderm and endoderm in vitro. It has been shown that the stem cells derived from bone marrow cells (BMCs) can regenerate cardiac myocytes after myocardial infarction (MI). Adult bone marrow mesenchymal stem cells have the ability to regenerate neural cells. Neural stem/progenitor cells (NS/PC) are ideal for treating central nervous system (CNS) diseases, such as Alzheimer's, Parkinson's and Huntington disease. However, there are important ethical issues about the therapeutic use of stem cells. Neurons, cardiac myocytes, hepatocytes, renal cells, blood cells, chondrocytes and adipocytes regeneration from BMCs are very important in disease control. It is known that limbal epithelial stem cells in the cornea can repair the eye sight and remove symptoms of blindness. Stem cell therapy (SCT) is progressing well in animal models, but the use of SCT in human remains to be explored further.

Field homogeneity improvement of maglev NdFeB magnetic rails from joints

An ideal magnetic rail should provide a homogeneous magnetic field along the longitudinal direction to guarantee the reliable friction-free operation of high temperature superconducting (HTS) maglev vehicles. But in reality, magnetic field inhomogeneity may occur due to lots of reasons; the joint gap is the most direct one. Joint gaps inevitably exist between adjacent segments and influence the longitudinal magnetic field homogeneity above the rail since any magnetic rails are consisting of many permanent magnet segments. To improve the running performance of maglev systems, two new rail joints are proposed based on the normal rail joint, which are named as mitered rail joint and overlapped rail joint. It is found that the overlapped rail joint has a better effect to provide a competitive homogeneous magnetic field. And the further structure optimization has been done to ensure maglev vehicle operation as stable as possible when passing through those joint gaps. The results show that the overlapped rail joint with optimal parameters can significantly reduce the magnetic field inhomogeneity comparing with the other two rail joints. In addition, an appropriate gap was suggested when balancing the thermal expansion of magnets and homogenous magnetic field, which is considered valuable references for the future design of the magnetic rails.

Dihydroartemisinin attenuates lipopolysaccharide-induced osteoclastogenesis and bone loss via the mitochondria-dependent apoptosis pathway

Dihydroartemisinin (DHA) is a widely used antimalarial drug isolated from the plant Artemisia annua. Recent studies suggested that DHA has antitumor effects utilizing its reactive oxygen species (ROS) yielding mechanism. Here, we reported that DHA is inhibitory on lipopolysaccharide (LPS)-induced osteoclast (OC) differentiation, fusion and bone-resorption activity in vitro. Intracellular ROS detection revealed that DHA could remarkably increase ROS accumulation during LPS-induced osteoclastogenesis. Moreover, cell apoptosis was also increased by DHA treatment. We found that DHA-activated caspase-3 increased Bax/Bcl-2 ratio during LPS-induced osteoclastogenesis. Meanwhile, the translocation of apoptotic inducing factor (AIF) and the release of cytochrome c from the mitochondria into the cytosol were observed, indicating that ROS-mediated mitochondrial dysfunction is crucial in DHA-induced apoptosis during LPS-induced osteoclastogenesis. In vivo study showed that DHA treatment decreased OC number, prevents bone loss, rescues bone microarchitecture and restores bone strength in LPS-induced bone-loss mouse model. Together, our findings indicate that DHA is protective against LPS-induced bone loss through apoptosis induction of osteoclasts via ROS accumulation and the mitochondria-dependent apoptosis pathway. Therefore, DHA may be considered as a new therapeutic candidate for treating inflammatory bone loss.

Open reduction and internal fixation for the treatment of fractures of the lateral humeral condyle with an early delayed presentation in children

Aims

The treatment of late presenting fractures of the lateral humeral condyle in children remains controversial.

Methods

We report on the outcome for 16 children who presented with a fracture of the lateral humeral epicondyle at a mean of 7.4 weeks (3 to 15.6) after injury and were treated surgically.

Results

The mean follow-up was four years (1.1 to 8.9), at which time the mean age of the patients was 8.7 years (3.2 to 17.8). The mean Dhillon functional score improved from 3.3 to 5.6 and the mean overall scores improved from 5.6 to 8.5. A total of seven patients had a fishtail deformity and eight had partial lateral epiphyseal closure. None had avascular necrosis. MRI showed an abnormal cartilage signal, incongruence of the joint surface and partial premature closure of the lateral physis in four patients.

Discussion

Neither age at the time of injury, the time interval between injury and operation, nor the pre-operative function were correlated with the incidence of complications. These results support the use of internal fixation for children with a lateral humeral epicondylar fracture with a delayed presentation. Take home message: Open reduction and internal fixation yielded a satisfactory outcome within 16 weeks in children with a lateral humeral epicondylar fracture with a delayed presentation. Cite this article: Bone Joint J 2016;98-B:244–8.

Intake of polyunsaturated fat in relation to mortality among statin users and non-users in the Southern Community Cohort Study

BACKGROUND AND AIMS

Consumption of polyunsaturated fatty acids (PUFA), especially the n3-series, may protect against cardiovascular disease (CVD), but recent randomized studies have failed to demonstrate these benefits. One of the prevailing hypotheses is that PUFA intake may not confer benefits beyond those provided by statins, but studies comparing statin users to non-users with regard to effects of PUFA are lacking.

METHODS AND RESULTS

Black and white men and women (n = 69,559) in the Southern Community Cohort Study were studied. Cox regression models adjusting for age, sex, race, BMI, recruitment site, education, income, smoking, diabetes, and dietary variables were used.

RESULTS

At baseline the mean ± SD age was 52 ± 9 years, 60% of participants were women, 54% had hypertension and 16% used statins. We observed modest inverse associations between n3-PUFA and n6-PUFA intake with mortality among non-statin users but not among statin users. In adjusted analyses, the HRs (95% CIs) for all-cause mortality (6,396 deaths over a median of 6.4 years) comparing the highest to the lowest quintile were 0.90 (0.82-1.00) for n3-PUFA and 0.80 (0.70-0.92) for n6-PUFA among non-statin users, whereas they were 1.06 (0.87-1.28) and 0.96 (0.78-1.19) for n3-PUFA and n6-PUFA, respectively, among statin users.

CONCLUSIONS

Our results suggest potential benefits of PUFA consumption on mortality which are only apparent in the absence of statin therapy. It seems prudent to consider the potential benefit of PUFA consumption in the primary prevention of CVD among patients who are not candidates for statin therapy but are at increased risk for CVD and mortality.

Dynamic changes of global DNA methylation and hypermethylation of cell adhesion-related genes in rat kidneys in response to ochratoxin A

Ochratoxin A (OTA), which is found in a variety of food products, is associated with the development of nephrotoxicity and carcinogenicity in rats and has raised public health concerns. A previous study in our laboratory indicated that OTA exposure induced cytotoxicity by decreasing global DNA methylation in vitro. However, the relationship between OTA-induced nephrotoxicity and DNA methylation changes in vivo remains unclear. The object of this study was to investigate whether OTA can change global DNA methylation or alter the expression of several critical tumour-related genes by inducing methylation modifications before carcinogenesis. We focused on the mechanism of action of OTA in regard to DNA methylation, including the expression of DNA methyltransferases and the regulation of specific cell signalling pathways. Dynamic and dose-dependent changes of global DNA methylation were observed during OTA-induced nephrotoxicity and probably associated with the expression of DNA methyltransferase 1. 13-week exposure of OTA caused hypermethylation in the promoters of critical cell adhesion-related genes, E-cadherin and N-cadherin, leading to reduction of the corresponding mRNA expression, accompanied by transcriptional activation of the Wnt and PI3K/AKT pathways. These findings suggested that long-term OTA exposure could disrupt DNA methylation profile, which might be one of the possible mechanisms of OTA-induced nephrotoxicity.