Let-7 family regulates HaCaT cell proliferation and apoptosis via the ΔNp63/PI3K/AKT pathway.

We evaluated the expression profiles of differentially expressed miRNAs (DEmiRNAs) involved in human fetal skin development via high-throughput sequencing to explore the expression difference and the regulatory role of miRNA in different stages of fetal skin development. Analysis of expression profiles of miRNAs involved collecting embryo samples via high-throughput sequencing, then bioinformatics analyses were performed to validate DEmiRNAs. A total of 363 miRNAs were differentially expressed during the early and mid-pregnancy of development, and upregulated DEmiRNAs were mainly concentrated in the let-7 family. The transfection of let-7b-5p slowed down HaCaT cell proliferation and promoted apoptosis, as evidenced by the cell counting kit-8 assay, quantitative real-time polymerase chain reaction, and flow cytometry. The double luciferin reporter assay also confirmed let-7b-5p and ΔNp63 downregulation through the combination with the 3'-untranslated region of ΔNp63. Moreover, treatment with a let-7b-5p inhibitor upregulated ΔNp63 and activated the phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) signaling pathway. The let-7b-5p caused a converse effect on HaCaT cells because of Np63 upregulation. Let-7b-5p regulates skin development by targeting ΔNp63 via PI3K-AKT signaling, contributing to future studies on skin development and clinical scar-free healing.

Improvement and Evaluation of a Device That Determines the Interfacial Shear Strength of Carbon Fiber/Polyphenylene Sulfide Composites.

This study improved homemade apparatus for characterizing the interfacial shear strength (IFSS) of carbon-fiber-reinforced polyphenylene sulfide (PPS/CF) composites. The upgraded generation II experimental device includes a newly developed experimental clamp for samples, as well as testing systems. Compared with the initial generation I apparatus and the commercial Toei instrument, the generation II device is easier and more efficient to operate. The average interfacial adhesion values obtained using these devices were consistently approximately 40 MPa, with relatively low data scatter, showing excellent repeatability and applicability during microbond tests. Notably, the generation II experimental device was equipped with an additional high-frequency data-capturing tool to identify the debonding peak force more precisely, which demonstrated a higher interfacial shear strength of 42.81 MPa during testing. Therefore, the new instrument was able to reflect the change in the interfacial stress state during the interface debonding process more accurately and reliably.

Real-Time Sniffing Mass Spectrometry Aided by Venturi Self-Pumping Applicable to Gaseous and Solid Surface Analysis.

Based on the Venturi self-pumping effect, real-time sniffing with mass spectrometry (R-sniffing MS) is developed as a tool for direct and real-time mass spectrometric analysis of both gaseous and solid samples. It is capable of dual-mode operation in either gaseous or solid phase, with the corresponding techniques termed as Rg-sniffing MS and Rs-sniffing MS, respectively. In its gaseous mode, Rg-sniffing MS is capable of analyzing a gaseous mixture with response time (0.8-2.1 s rise time and 7.3-9.6 s fall time), spatial resolution (<80 µm), three-dimensional diffusion imaging, and aroma distribution imaging of red pepper. In its solid mode, an appropriate solvent droplet desorbs the sample from a solid surface, followed by the aspiration of the mixture using the Venturi self-pumping effect into the mass spectrometer, wherein it is ionized by a standard ion source. Compared with the desorption electrospray ionization (DESI) technique, Rs-sniffing MS demonstrated considerably improved limit of detection (LOD) values for arginine (0.07 µg/cm2 Rs-sniffing vs 1.47 µg/cm2 DESI), thymopentin (0.10 µg/cm2 vs 2.67 µg/cm2), and bacitracin (0.16 µg/cm2 vs 2.28 µg/cm2). Rs-sniffing is applicable for the detection of C60(OCH3)6Cl-, an intermediate in the methoxylation reaction involving C60Cl6 (solid) and methanol (liquid). The convenient and highly sensitive R-sniffing MS has a characteristic separation of desorption from the ionization process, in which the matrix atmosphere of desorption can be interfaced by a pipe channel and self-pumped by the Venturi effect with consequent integration using a standard ion source. The R-sniffing MS operates in a voltage-, heat-, and vibration-free environment, wherein the analyte is ionized by a standard ion source. Consequently, a wide range of samples can be analyzed simultaneously by the R-sniffing MS technique, regardless of their physical state.

Nitrogen-Embedded Quintuple [7]Helicene: A Helicene-Azacorannulene Hybrid with Strong Near-Infrared Fluorescence.

Herein, a nitrogen-embedded quintuple [7]helicene (N-Q7H) with an azapentabenzocorannulene core, which can be considered to be a helicene/azacorannulene hybrid π-system, was synthesized from azapentabenzocorannulene in a three-step process. N-Q7H is the first example of a multiple helicene with an azabuckybowl core. Single-crystal X-ray diffractometry unambiguously confirmed the structure of the propeller-shaped hybrid π-system. Owing to nitrogen-atom doping in the multiple helicenes and effective hybridization between the helicene and azacorannulene, N-Q7H exhibits considerably redshifted absorption and emission (yellow-to-green color change and green-to-near-infrared fluorescence change) relative to the azapentabenzocorannulene core. The broad absorption from the ultraviolet-visible to the NIR region is ascribable to the allowed transition between the highest occupied molecular orbital and the lowest unoccupied molecular orbital after symmetry breaking, as revealed by density functional theory calculations. Compared to previous propeller-shaped multiple helicenes with corannulene or hexabenzocoronene (etc.) as cores, N-Q7H demonstrates a significantly higher NIR fluorescence quantum efficiency of 28%. Additionally, the chiral-resolution and redox properties of N-Q7H were investigated. The excellent photophysical and inherent chiral properties of N-Q7H suggest that azapentabenzocorannulene can be used as an outstanding nitrogen-embedded core to construct novel multiple helicenes with wide application potential, including as NIR fluorescent bio-probes.

Effects of fluoride on the proliferation and activation of osteoblasts by regulating methylation of the DNA repair genes MGMT and MLH1.

INTRODUCTION: Fluoride can induce the proliferation and activation of osteoblasts, resulting in skeletal fluorosis progression; however, the specific mechanism is unclear. METHODS: Cell proliferation was examined using the MTT assay. Flow cytometry was performed to detect the cell cycle distribution. Alkaline phosphatase (ALP) was calculated to evaluate bone formation and turnover. Gene methylation was examined using the MSP assay. mRNA and protein expression levels were assessed using qRT-PCR and Western blot assays. RESULTS: Low-concentration NaF treatment promoted the cell cycle progression of osteoblasts to S-phase, thus accelerating cell proliferation and activation in a concentration-dependent manner. In addition, the methylation of the MGMT and MLH1 genes was increased, and their mRNA expression was reduced. Furthermore, the DNA methyltransferase inhibitor 5-AZA-dC suppressed cell viability, cell number in S-phase, ALP activity and osteogenesis-related protein levels in osteoblasts treated with low doses of NaF. Meanwhile, 5-AZA-dC suppressed the increase in MGMT and MLH1 gene methylation in osteoblasts treated with low doses of NaF, leading to enhanced expression of MGMT and MLH1 mRNA. CONCLUSION: NaF treatment led to methylation of the DNA repair genes MGMT and MLH1 in osteoblasts, resulting in cell proliferation and activation and causing the development of skeletal fluorosis.

Early 1,25-Dihydroxyvitamin D3 Supplementation Effectively Lowers the Incidence of Type 2 Diabetes Mellitus via Ameliorating Inflammation In KK-Ay Mice.

Few studies have been performed to investigate the effect of vitamin D supplementation and T2DM in type 2 diabetic animal models. The present study aimed to explore the relationship between early 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and the incidence of T2DM and determine whether early 1,25(OH)2D3 supplementation was associated with inflammation in KK-Ay mice. The KK-Ay mice were divided into 4 vitamin D treatment groups, the low-dose vitamin D supplementation group (VDS-L, 1.5 µg/kg 1,25(OH)2D3), moderate-dose vitamin D supplementation group (VDS-M, 3.0 µg/kg 1,25(OH)2D3), high-dose vitamin D supplementation group (VDS-H, 6.0 µg/kg 1,25(OH)2D3) and the model control group (MC). C57BL/6J mice were used as the controls. The treatment period lasted for 9 wk. During this treatment period, fasting blood glucose (FBG) level of the mice was measured on a weekly basis. The levels of lipid profile, insulin and inflammation biomarkers were determined after 9 wk of 1,25(OH)2D3 intragastric gavage. After 9 wk of 1,25(OH)2D3 intragastric gavage, FBG level was significantly decreased in the vitamin D treatment groups compared with the MC group. The number of T2DM incidence in the VDS-L group (n=7), VDS-M group (n=5) and VDS-H group (n=3) was lower than those in the MC group (n=10) on week 9. Moreover, serum C-reactive protein (CRP) and interleukin-6 (IL-6) in the vitamin D treatment groups were significantly suppressed by 1,25(OH)2D3 administration compared with the MC group. Early 1,25(OH)2D3 supplementation could effectively lower the incidence of T2DM via ameliorating inflammation in KK-Ay mice.

Effect of acupoint catgut embedding in chronic fatigue syndrome patients: A protocol for systematic review and meta-analysis.

BACKGROUND: Chronic fatigue syndrome (CFS) is a relatively complex and disabling illness with a substantial economic burden and functional impairment. Until now, many CFS patients lack appropriate healthcare. Acupoint catgut embedding is an effective and emerging alternative therapy for CFE. With this research, we endeavor to investigate the effect and safety of ACE for CFS. METHODS: Eight databases will be searched from inception to December 2020: PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chong-Qing VIP database, and Wan-fang database. We regard studies as eligible for inclusion if they were RCTs done in CFS patients, compare acupoint catgut embedding to another treatment strategy, and report fatigue changes at the end of the intervention period. Two independent reviewers complete the study selection, data extraction, and the risk of bias assessment. We assess pooled data using a random-effects model through Revman software (v.5.3) and Stata (version 15.0). ETHICS AND DISSEMINATION: Ethics approval is not required because the individual patient data will not be involved, with no privacy concerns. This systematic review and meta-analysis will provide a reference for CFS patients and clinicians on the non-drug interventions. We will publish and disseminate the results of this review in a peer-reviewed journal or relevant conference. OSF REGISTRATION NUMBER: 10.17605/OSF.IO/7SHD9 (https://osf.io/7shd9).

The Association of Serum Vitamin D Deficiency and Metabolic Risk Factors in Chinese Adults with Prediabetes: A Cross-Sectional Study.

The association of serum vitamin D deficiency and metabolic risk factors in Chinese adults with prediabetes (PreDM) has not been investigated. The present study aimed to investigate the association of serum vitamin D deficiency and metabolic risk factors in Chinese adults with PreDM. In this cross-sectional study, we stratified 412 PreDM patients into vitamin D sufficient, vitamin D insufficient and vitamin D deficient subgroups. The physical examination data was collected. Serum 25-hydroxyvitamin D3 [25(OH)D3] were measured by high performance liquid chromatography. The prevalence of vitamin D deficiency and insufficiency in PreDM patients were 30.58% and 26.70%, respectively. Compared with the vitamin D deficient group, the prevalence of metabolic syndrome, central obesity, hyperglycemia and hypertension were higher than those in the vitamin D insufficient or sufficient group (p<0.05). Moreover, the prevalence of dyslipidemia in the vitamin D deficient group was higher than those in the vitamin D sufficient group (p<0.05). We observed an inverse relationship between 25(OH)D3 levels and waist circumference, triglyceride, and serum uric acid (ß=-0.315; ß=-0.134; ß=-0.239), a positive relationship between 25(OH)D3 levels and high-density lipoprotein cholesterol (ß=0.197) after adjusting for age, sex and body mass index. Vitamin D deficiency is very common among PreDM patients in China and this deficiency is related to metabolic risk factors.

Enhancement of the efficiency of oocyte vitrification through regulation of histone deacetylase 6 expression.

OBJECTIVE: Successful oocyte vitrification (OV) is critical for cryopreservation of the oocytes from female patients with infertility, polycystic ovaries, and gynecologic cancers. Recent evidence suggests that relatively low levels of histone acetylation are critical for maintenance of the maturation capacity of cryopreserved oocytes. However, previous studies have only demonstrated a key role of histone deacetylases (HDAC) 1 and 2 in the cryopreservation of oocytes. METHODS: In this study, we investigated the role of HDAC6 in these settings. We found that mouse oocytes with low HDAC6 levels decreased survival rate, cleavage rate, and blastocyst rate after OV. Bioinformatics analyses were used to predict HDAC6-targeting microRNAs (miRNAs), while the functional binding of miRNAs to HDAC6 mRNA was evaluated by a dual luciferase reporter assay. RESULTS: Among all HDAC6-targeting miRNAs, we detected expression of miR-558, miR-527, and miR-762 in mouse oocytes. Specifically, we found that only miR-762 significantly inhibited protein translation of HDAC6 via binding to the 3'-UTR of the HDAC6 mRNA. Transfection of oocytes with HDAC6 or antisense of miR-762 significantly increased the survival rate, the cleavage rate, and blastocyst rate after OV. CONCLUSION: As a result, our data suggest that induction of HDAC6 levels by miR-762 suppression may improve the current protocol for OV.

Sniffing with mass spectrometry.

Gaseous compounds are usually on-line detectable on sensors. The limitations of conventional sensors are suffering from incapability for exactly identifying multiple components as well as incompatibility to possible toxicants in every odor sample. Herein, we discuss an inlet modification to the laboratory standard mass spectrometer, inspired by the sensitive olfactory systems of animals, for direct sniffing, established by connecting a mini pump to the nebulizer gas tubing. The modified mass spectrometry method-sniffing-mass spectrometry (sniffing-MS)-can acquire detailed fingerprint spectra of mixed odors and shows high tolerance to toxicants. Furthermore, the method has a low limit of detection in the order of parts per trillion and is a 'sampling-free' technique for analyzing various gaseous compounds simultaneously, thus offering versatility for smelling daily commodities, tracking diffusion, and locating position of odors. Sniffing-MS can mimic or even surpass the olfaction of animals and is applicable for analyzing gaseous/volatile compounds, especially those polar compounds, in a simple manner depending on the intrinsic molecular mass-to-charge ratio.

Wellens syndrome caused by spasm of the proximal left anterior descending coronary artery.

Electrocardiographic characteristics of Wellens syndrome (WS) consist of deeply inverted T waves or biphasic T waves in anterior precordial leads. Studies have shown that patients with WS have critical stenosis or complete obstruction of the proximal left anterior descending coronary artery (LAD) and high risk for the development of extensive anterior myocardial infarction. Here, we reported a case presenting with WS and with a small plaque in the proximal LAD and slow flow in the LAD other than significant stenosis of the proximal LAD detected by coronary angiography. The mechanisms for WS of our case are discussed.

The role of the conjugate bridge in electronic structures and related properties of tetrahydroquinoline for dye sensitized solar cells.

To understand the role of the conjugate bridge in modifying the properties of organic dye sensitizers in solar cells, the computations of the geometries and electronic structures for 10 kinds of tetrahydroquinoline dyes were performed using density functional theory (DFT), and the electronic absorption and fluorescence properties were investigated via time dependent DFT. The population analysis, molecular orbital energies, radiative lifetimes, exciton binding energies (EBE), and light harvesting efficiencies (LHE), as well as the free energy changes of electron injection ( ) and dye regeneration ( ) were also addressed. The correlation of charge populations and experimental open-circuit voltage (Voc) indicates that more charges populated in acceptor groups correspond to larger Voc. The elongating of conjugate bridge by thiophene units generates the larger oscillator strength, higher LHE, larger absolute value of , and longer relative radiative lifetime, but it induces the decreasing of EBE and . So the extending of conjugate bridge with thiopene units in organic dye is an effective way to increase the harvest of solar light, and it is also favorable for electron injection due to their larger . While the inversely correlated relationship between EBE and LHE implies that the dyes with lower EBE produce more efficient light harvesting.

Serum uric acid and appropriate cutoff value for prediction of metabolic syndrome among Chinese adults.

The relation between serum uric acid and metabolic syndrome is observed not only with frank hyperuricemia but also with serum uric acid levels within the normal range. The current "normal" range set for hyperuricemia often fails to identify patients with potential metabolic disorders. We investigate the association between serum uric acid within the normal range and incident metabolic syndrome risk, and further to determine the optimal cut-off value of serum uric acid for the diagnosis or prediction of metabolic syndrome. A total of 7399 Chinese adults (2957 men and 4442 women; ≥20 years) free of metabolic syndrome were followed for 3 years. During the 3-year follow-up, 1190 normouricemic individuals developed metabolic syndrome (16.1%). After adjusting the associated variables, the top quartile of serum uric acid levels was associated with higher metabolic syndrome development compared with the bottom quartile in men (hazard ratio (HR), 1.29; p<0.05) and women (HR, 1.62; p<0.05). ROC curve analysis indicated that the optimal cut-off values for serum uric acid to identify metabolic syndrome were 6.3 mg/dl in men and 4.9 mg/dl in women. Our results suggested that high baseline serum uric acid levels within the normal range predict future development of metabolic syndrome after 3 y of follow-up.

Hierarchical CdSe-gold hybrid nanocrystals: synthesis and optical properties.

The synthesis of hybrid nanostructures with controlled size, shape, composition and morphology has attracted increasing attention due to the fundamental and applicable interest. Here, we demonstrate the synthesis and optical properties of hierarchical CdSe-Au hybrid nanostructures with zinc blende (ZB) CdSe nanocrystals (NCs). For 3.5 nm ZB CdSe NCs, one Au cluster was deposited on each CdSe NC. Nevertheless, several Au clusters were selectively deposited on the apexes of 5 nm and 8 nm ZB CdSe NCs, resulting from the different reactivity of crystal facets. Furthermore, hierarchical CdSe-Au nanostructures with complex morphology were organized with the isolated CdSe-Au hybrid NCs by the coalescence of Au domains on the CdSe-Au hybrid NCs. UV-Vis spectra revealed a red tail upon the deposition of Au clusters. The chemical joint of Au on CdSe NCs was further confirmed by fluorescence quenching. The optical limiting performance of CdSe-Au hybrid NCs dispersed in toluene was investigated at 532 nm using a Nd:YAG laser with the pulse width of 8 ns.

N-[Bis(4-fluoro-phen-yl)methyl-ene]aniline.

The title compound, C(19)H(13)F(2)N, was synthesized by an addition reaction of bis-(4-fluoro-phen-yl)methanone with aniline. The dihedral angles formed by the fluoro-benzene rings with the aniline ring are 81.04 (5) and 64.15 (5)°. In the crystal packing, inter-molecular C-H⋯F hydrogen bonds link mol-ecules into zigzag chains parallel to the c axis.

[A case control study on the relationship between trace elements and human neural tube defects].

OBJECTIVE: To explore the relationship between multi-trace elements levels in hair and human neural tube defects as well as other risk factors. METHODS: Using 88 paired cases and controls, an 1:1 matched case control study was carried out. The study subjects were collected from the China-U. S. Collaborative Project on Neural Tube Defects Prevention and Birth Defects Surveillance System. Risk factors were obtained by field investigation with standardized questionnaires and hair trace elements levels were determined by AAS and ICP-MS methods. Microwave digestion was used to digest hair samples. The detected elements would include three groups, namely nutritional elements: Cr, Mn, Cu, Zn, Co, Mo; toxic elements: Pb, As, Cd, Hg; and Lanthanons: Y, La, Pr, Nd. Cox Proportional Hazard Regression Model was used to perform risk factors analysis. RESULTS: Pregnancy fever appeared to be a risk factor of neural tube defects (OR = 6.525, P = 0.034) while hair zinc level (OR = 0.541 microg/100 g, P = 0.02) and times of prenatal physical examination (OR = 0.634, P < 0.001) served as two protective factors appeared in the last model. CONCLUSION: Zinc deficiency might serve as a risk factor for human neural tube defects, suggesting that the avoidance of pregnancy infection together with more periodical prenatal physical examination might reduce the incidence of neural tube defects.