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A reliable copper-mediated nucleophilic radiosynthesis of the PET imaging probe [18F]FBPA was developed using novel aryldiboron precursors. The carrier-free [18F]FBPA with radiochemical purity >99% was prepared routinely via the two-step synthesis with an automatic module and can be used for clinical PET imaging of tumours.

In this work, free radical photopolymerization of trimethylolpropane trimethacrylate (TMPTMA) is initiated. We investigated the corresponding photoreactivity by using Type II photoinitiator (PI) systems based on thioxanthone (TX) as a hydrogen acceptor and five amine-type molecules, such as N-phenylglycine (NPG), triethylamine (TEA), triethanolamine (TEOA), 2,2′-(4-methylphenylimino)diethanol (p-TDEA), and N-phenyldiethanolamine (n-PDEA), as hydrogen donors. Their photochemical and photophysical properties are studied. The TX hydrogen acceptor displayed rather red-shifted compared to all the hydrogen donor compounds. The hydrogen donor compounds exhibited the absorption band at lower than 300 nm, which followed the trend of p-TDEA > n-PDEA > NPG > TEOA > TEA. All the packages exhibit good electron-transfer ability by the calculation of the free energy changes (ΔGET) through cyclic voltammetry (CV) measurement. However, the hydrogen donors with different steric hindrance, secondary, and tertiary amines have a decisive influence on the photoreactivity; that is, the TX/TEOA package shows the best double-bond conversion (DC) efficiency than other formulations under similar weight ratios (hydrogen acceptor: hydrogen donor = 1:2 wt%). We then conduct the photoreactivity based on TX/TEOA formulation with different weight ratios. The DC values are in the order of 1:2 wt% > 1.5:1.5 wt% > 2:1 wt%. Under suitable amount of hydrogen donor, the TX/TEOA-based formulation also exhibits stable DC value at air atmosphere.

A mild HPLC method for the quality control of [18F]sodium fluoride solution for injection was developed. The method used anion exchange column for separation, UV and online radio-detectors for fluoride content and fluorine-18 determination. A mixture of 100 mM sodium acetate and 25 mM sodium chloride was chosen as mobile phase. The method was validated for system suitability, specificity, fluoride concentration and radiochemical purity determination with good linearity, accuracy and precision. The good robustness of the system was also verified, enabling routine analysis of fluoride content and radiochemical purity of the [18F]sodium fluoride product.

In this paper, polymeric graphitic carbon nitride (pgCN) with disordered in-plane and ordered inter-plane structure was prepared via a two-step method of low-temperature solvothermal synthesis and post-calcination, using dicyandiamide and cyanuric chloride mixture as raw materials and acetonitrile as solvent. Disordered in-plane structure of the pgCN was confirmed by X-ray diffraction (XRD), transmission electron microscope (TEM) and electron diffraction (ED). The microstructure, chemical states, bandgap, charge migration and photocatalytic performance of the pgCN were compared with that of classic bulk graphitic carbon nitride (bulk g-C3N4) obtained from melamine by calcination and its post-hydrothermal product. The pgCN showed highly efficient in both the photodegradation of Rhodamine B (RhB) and hydrogen evolution reaction (HER) benefiting from disordered–ordered hybrid plane structure which can inhibit photoelectron recombination and provide higher charge separation efficiency. Under visible light irradiation, the average HER rate of pgCN could reach 4541 μmol h−1 g−1, which is 18.2 times higher than that of bulk g-C3N4 crystal.

In this study, three triphenylamine-based hexaarylbiimidazole (HABI) derivatives featuring different numbers of methoxy groups (none for HABI1, two for HABI2, and four for HABI3) have been synthesized. For comparison, a common hydrogen acceptor photoinitiator, ocl-HABI (2-chlorohexaarylbiimidazole), was also applied to compare the corresponding properties. The new HABIs displayed a more red-shifted and higher molar extinction coefficient than ocl-HABI with the absorption region extended to visible light. A larger free radical concentration of HABIs was also achieved, which was confirmed via electron paramagnetic resonance (ESR) spectroscopy. These visible light-sensitive HABIs or ocl-HABI in combination with a suitable hydrogen donor, i.e., N-phenyl glycine (NPG) were utilized as photoinitation systems for conventional radical polymerization (RDRP). All the packages exhibited good electron-transfer ability by the calculation of the free energy changes (ΔGET). The HABI1/NPG system exhibited the best double bond conversion efficiency and outperformed the corresponding ocl-HABI/NPG-based formulation under similar UV light source testing conditions. We then employed the HABI1/NPG and ocl-HABI/NPG systems for LED light source testing. Again, HABI1/NPG had better photocuring conversion efficiency and shorter time at maximum heat flow than ocl-HABI/NPG, indicating that the HABI1/NPG system can be applied to light curing applications under different light sources, such as UV and LED.

SARS-CoV-2 infection-induced hyper-inflammation links to the acute lung injury and COVID-19 severity. Identifying the primary mediators that initiate the uncontrolled hypercytokinemia is essential for treatments. Mast cells (MCs) are strategically located at the mucosa and beneficially or detrimentally regulate immune inflammations. Here we showed that SARS-CoV-2-triggeed MC degranulation initiated alveolar epithelial inflammation and lung injury. SARS-CoV-2 challenge induced MC degranulation in ACE-2 humanized mice and rhesus macaques, and a rapid MC degranulation could be recapitulated with Spike-RBD binding to ACE2 in cells; MC degranulation alterred various signaling pathways in alveolar epithelial cells, particularly, led to the production of pro-inflammatory factors and consequential disruption of tight junctions. Importantly, the administration of clinical MC stabilizers for blocking degranulation dampened SARS-CoV-2-induced production of pro-inflammatory factors and prevented lung injury. These findings uncover a novel mechanism for SARS-CoV-2 initiating lung inflammation, and suggest an off-label use of MC stabilizer as immunomodulators for COVID-19 treatments.Graphical abstractIn BriefSARS-CoV-2 triggers an immediate mast cell (MC) degranulation, which initiates the alveolar epithelial inflammation and disrupts the tight junction. MC stabilizers that block degranulation reduce virus-induced lung inflammation and injury.HighlightsThe binding of RBD of Spike protein of SARS-CoV-2-to ACE2 receptor protein triggers an immediate MC degranulationMC degranulation induces transcriptomic changes include an upregulated inflammatory signaling and a downregulated cell-junction signalingMC degranulation leads to alveolar epithelial inflammation and disruption of tight junctionsMC stabilizer that inhibits degranulation reduces SARS-CoV-2-induced lung inflammation and injury in vivo

Extracellular vesicles (EVs) are heterogeneous nanoparticles actively released by cells that comprise highly conserved and efficient systems of intercellular communication. In recent years, numerous studies have proven that EVs play an important role in the field of bone tissue engineering (BTE) due to several advantages, such as good biosafety, stability and efficient delivery. However, the application of EVs therapies in bone regeneration has not been widely used. One of the major challenges for the application of EVs is the lack of sufficient scaffolds to load and control the release of EVs. Thus, in this review, we describe the most advanced current strategies for delivering EVs with various biomaterials for the use in bone regeneration, the role of EVs in bone regeneration, the distribution of EVs mediated by biomaterials and common methods of promoting EVs delivery efficacy with a focus on biomaterial properties.

Solution-processed bulk heterojunction (BHJ) solar cells based on ternary blends have previously achieved high power conversion efficiencies (PCEs). In this study, we obtained a combination of good cell performance and high thermal stability for an inverted ternary organic solar cell based on a single polymer donor (PTB7-Th) and two acceptors: one a polymer (N2200) and the other a fullerene component (PC71BM). The ternary blended film based on PTB7-Th:N2200:PC71BM at a composition of 2:0.5:2.5 (w/w/w) featured suitable cascade energy levels, a broad comprehensive absorption region, and smooth interfaces; its corresponding device exhibited a best PCE of 6.2%, an open-circuit voltage of 0.82 V, and a short-circuit current density of 14.4 mA cm−2. After introducing 1% of 1,8-diiodoctane (DIO), the highest PCE reached 7.7%. Furthermore, this ternary cell exhibited good long-term thermal stability after annealing at 100 °C for 1000 h.

In this work, a three dimensional graphene-multiwalled carbon nanotubes (3DG-MWCNTs) network is successfully fabricated on the surface of glassy carbon electrode (GCE) using pulse potential method (PPM) in a graphene oxide-multi walled carbon nanotubes (GO-MWCNTs) homogeneous dispersion. Scanning electron microscopy (SEM) images and electrochemical experiments confirmed the 3D structure of interpenetrated graphene-MWCNTs network and excellent electrochemical performance. The 3DG-MWCNTs network was presented to develop a sensitive voltammetric sensor for detection of natamycin. Systematic electrochemical tests demonstrate that the 3DG-MWCNTs network modified electrode can effectively increase response to the oxidation of natamycin due to the large accessible surface area as well as its excellent conductivity. Under optimized conditions, the voltammetric sensor showed a linear relationship in the range of 5.0 × 10−8–2.5 × 10−6 mol L−1 and a low detection limit of 1.0 × 10−8 mol L−1. Moreover, the proposed method was also applied for detection of natamycin content in real samples (commercial red wine and beverage).

This study investigated the effect of konjac glucomannan (KGM) of different molecular weight on fecal microflora against antibiotic disturbance. KGM (~1.8 × 107 Da) was partially hydrolysed with trifluoroacetic acid (TFA) for 10 and 60 min to KGM1 (~2.1 × 104 Da) and KGM2 (7413 Da), respectively. The acid treatment caused significant reduction of intrinsic viscosity, average molecular weight (MW) and particle size of KGM, but brought limited change to the molecular structure. Low-MW KGM2 showed the most significant effect on fecal microflora in the presence of two common antibiotics (ampicillin and clindamycin), by increasing the relative abundance of Bifidobacteriaceae while decreasing the proportion of Enterobacteriaceae. Additionally, both the native and acid-treated KGM counteracted the adverse influence of antibiotics on the production of short chain fatty acids. The results have demonstrated the effect of KGM on gut microbiota with antibiotic disturbance.

Several HIV-1 subtypes are co-circulating among various high-risk groups in China, and an increasing prevalence of CRF01_AE was observed among MSM (men who have sex with men) within recent years. Patients infected with CRF01_AE may experience a more rapid disease progression than patients infected with non-CRF01_AE; however, the underlying mechanisms remains elusive. HIV-1 Nef is a multifunctional protein and plays critical roles in viral pathogenesis. Nef downregulates CD4 and human leukocyte antigen (HLA) to promote viral transmission and escape from the host immune response. In this study, we investigated the CD4 downmodulation activity of Nef proteins isolated from HIV-1 CRF01_AE and analyzed a potential relationship of Nef's capacity to downregulate CD4 with disease progression. We found that the majority of these Nefs from HIV-1 CRF01_AE efficiently downregulated CD4; Nefs with weaker CD4 downmodulation activity tended to be associated with higher CD4 levels and lower viral loads. Further elucidation revealed that amino acid residues at positions 3, 168, and 169 of CRF01_AE Nefs were associated with the capacity to downregulate CD4. Our data suggest that the capacity of Nef-mediated CD4 downregulation is not the only determinant for controlling disease progression, and other host and viral factors should be considered to explain the rapid disease progression of patients infected with HIV-1 CRF01_AE.

Cellular metabolic pathways that are altered by HIV-1 infection may accelerate disease progression. Dysfunction in tryptophan (Trp) metabolism has been observed clinically in association with accelerated HIV-1 pathogenesis, but the mechanism responsible was not known. This study demonstrates that Trp metabolites augment the activation of aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, to promote HIV-1 infection and transcription. These findings not only elucidate a previously unappreciated mechanism through which cellular Trp metabolites affect HIV pathogenesis but also suggest that a downstream target AHR may be a potential target for modulating HIV-1 infection., Multiple cellular metabolic pathways are altered by HIV-1 infection, with an impact on immune activation, inflammation, and acquisition of non-AIDS comorbid diseases. The dysfunction of tryptophan (Trp) metabolism has been observed clinically in association with accelerated HIV-1 pathogenesis, but the underlying mechanism remains unknown. In this study, we demonstrated that the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, is activated by Trp metabolites to promote HIV-1 infection and reactivation. AHR directly binds to the HIV-1 5′ long terminal repeat (5′-LTR) at the molecular level to activate viral transcription and infection, and AHR activation by Trp metabolites increases its nuclear translocation and association with the HIV 5′-LTR; moreover, the binding of AHR with HIV-1 Tat facilitates the recruitment of positive transcription factors to viral promoters. These findings not only elucidate a previously unappreciated mechanism through which cellular Trp metabolites affect HIV pathogenesis but also suggest that a downstream target AHR may be a potential target for modulating HIV-1 infection.

Accounting for a quarter of the population in the United States, the millennial generation is believed to have stronger buying power than other generations. But does targeting orange juice marketing to millennials, and, in particular, millennial parents, reap rewards? This 4-page fact sheet written by Yan Heng, Ronald W. Ward, and Lisa A. House and published by the UF/IFAS Food and Resource Economics Department presents the results of a survey examining several generations and their impact on demand for orange juice to find out whether targeting this one is a wise marketing strategy. https://edis.ifas.ufl.edu/fe1089

Microdamage accumulation in bone is one of the mechanisms for energy dissipation during the fracture process. Changes in the ultrastructure and composition of bone constituents due to aging or diseases could affect microdamage accumulation. Low concentration (1 mM) of sodium fluoride (NaF) has been used in this study to investigate the effect of ultrastructural changes on microdamage accumulation in mouse tibias following free-fall impact loadings. Twenty-two tibias were divided randomly into control and NaF-treated groups. Free-fall impact loading was conducted twice on each tibia to produce microdamage. The elastic modulus of NaF-treated tibias decreased significantly after the impact loadings, while there was no significant difference in the modulus of untreated samples between pre- and post-damage loadings. Microdamage morphology analysis showed that less and shorter microcracks existed in NaF-treated tibias compared with control bones. Meanwhile, more and longer microcracks were observed in tensile regions in untreated samples compared with that in compressive regions, whereas no significant difference was observed between tensile and compressive regions in NaF-treated bones. The results of this study indicate that more energy is required to generate microcracks in NaF-treated bone than in normal bone. A low concentration of fluoride treatment may increase the toughness of bone under impact loading. This study focused on the effect of ultrastructural changes on microdamage in bones under impact loadings. The elastic modulus of the NaF-treated tibias decreased significantly after impact loadings. Less and shorter microcracks existed in NaF-treated tibia bones. More energy is required to generate microdamage in NaF-treated bones. A low concentration of fluoride treatment may increase the toughness of bone.

Microdamage would be accumulated in bone due to high-intensity training or even normal daily activity, which may consequently cause fragility fracture or stress fracture. On the other hand, microdamage formation serves as a toughening mechanism in bone. However, the mechanisms that control microdamage initiation and accumulation in bone are still poorly understood. Our previous finite element model indicated that different interfacial properties between mineral and collagen in bone may lead to distinct patterns of microdamage accumulation. Therefore, the current study was designed to examine such prediction and to investigate the role of water and mineral–collagen interactions on microdamage accumulation in bone. To address these issues, 48 mice femurs were divided randomly into four groups. These groups were dehydrated or treated with perfluorotripropylamine (PFTA) or NaF solution to change water distribution and mineral–collagen interfacial bonding in bone. After three-point bending fatigue tests, the types of microdamage (i.e., linear microcracks or diffuse damage) formed in bone were compared between different groups. The results suggested that (1) bone tissues with strong mineral–collagen interfacial bonding facilitate the formation of linear microcraks, and (2) water has little contribution to the growth of microcracks. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:217–223, 2014.

Total gaseous mercury (TGM) concentration in ambient air, particulate-bound mercury concentrations and particulate-bound mercury contents in total suspended particles (TSP) from locations in Central Taiwan were measured and discussed relative to their ranges and potential sources. Meteorological conditions in terms of average temperature, wind direction, wind speed, and humidity were also monitored at a traffic sampling site in Sha-Lu central Taiwan from July 2011 to November 2011. The results revealed that the average concentrations of total gaseous mercury (TGM) and particulate-bound mercury in TSP were 8.73±5.53 (ng/m3) and 0.000164±0.00007 (ng/m3), respectively. The monthly average TGM concentrations were highest in July (17.50±4.79 ng/m3) and lowest in November (4.10±0.72 ng/m3). The monthly average particulate-bound mercury concentrations were highest in July (0.000293±0.00021 ng/m3) and lowest in November (0.000109±0.00002 ng/m3). The average particulate-bound mercury Hg(p) contents were 0.15 (ng/g...

Tumor suppressor p53 has been implicated in cell stress response and determines cell fate of either growth arrest or apoptosis. Heat shock proteins (Hsps) expressed under stress usually confer survival protection to the cell or interruption in the apoptotic pathways. Although Hsp90 can physically interact with p53, whether or not the hsp90 gene is influenced downstream of p53 in UV irradiation-induced apoptosis remains unclear. We have found that the level of p53 is elevated with the decline of Hsp90 in UV-irradiated cells and that malfunction of Hsp90, as inhibited by geldanamycin, enhances the p53-involved UV irradiation-induced apoptosis. In addition, the expression of the hsp90beta gene was reduced in both UV-irradiated and wild type p53-transfected cells. These results suggest a negative correlation between the trans factor p53 and a chaperone gene hsp90beta in apoptotic cells. Mutation analysis demonstrated that the p53 binding site in the first exon was indispensable for p53 regulation on the hsp90beta gene. In addition, with p53 bound at the promoter of the hsp90beta gene, mSin3a and p300 were differentially recruited in UV irradiation-treated or untreated Jurkat cells in vivo. The evidence of p53-repressed hsp90beta gene expression in UV-irradiated cells shed light on a novel pathway of Hsp90 in the survival control of the stressed cells.

Pyrolysis characteristics and mechanism of tobacco stem were studied by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS), thermogravimetric analyzer coupled with Fourier transform infrared spectrometry, and mass spectrometry (TG-FTIR and TG-MS) techniques. The composition of evolved volatiles from fast pyrolysis of tobacco stem was determined by Py-GC/MS analysis, and the evolution patterns of the major products were investigated by TG-FTIR and TG-MS. Py-GC/MS data indicated that furfural and phenol were the major products in low temperature pyrolysis, and these were generated from depolymerization of cellulose. Indene and naphthalene were the major products in high temperature pyrolysis. TG-FTIR and TG-MS results showed that CO, CO2, phenols, aldehydes, and ketones were released between 167ºC and 500ºC; at temperatures >500ºC, CO and CO2 were the main gaseous products.

Specificity protein 1 (Sp1) is often overexpressed in cancer cells. Its binding sites are known to exist in the phosphatase and tension homolog deleted on chromosome 10 (PTEN) promoter. In this study, we hypothesized that Sp1 negatively regulates PTEN expression. We used several cell lines to determine the effects of Sp1. The results showed that Sp1 overexpression inhibited the expression and promoter activity of PTEN and correspondingly upregulated AKT phosphorylation, whereas Sp1 knockdown upregulated the expression and promoter ability of PTEN and downregulated AKT phosphorylation. Moreover, a series of deletion and site-directed mutations of the PTEN promoter indicated that Sp1 can inhibit PTEN promoter activity through a specific Sp1-binding site at the PTEN core promoter in vivo. Meanwhile, non-acetylated Sp1, with its loss of DNA binding activity, failed to inhibit the expression and promoter activity of PTEN. Histone deacetylase 1 was necessary for Sp1 to inhibit PTEN expression. The inverse expression of Sp1 and PTEN was found in tongue cancer cells and salivary adenoid cystic cancer (SACC)-LM cells (possessing higher potential for lung metastasis than SACC-83) as compared with that in adjacent normal tissue and SACC-83 cells, respectively. Sp1 knockdown decreased the migration and invasion of SACC-LM cells, whereas Sp1 overexpression increased the migration and invasion of SACC-83 cells. Overall, these results suggest that Sp1 is involved in the development and invasiveness of cancer through inhibition of PTEN.

A LC-diode array detection (DAD)-ESI-MS/MS method was established for the online characterization and identification of saikosaponins (SSs) from extracts of roots of Bupleurum scorzonerifolium Willd, B. marginatum var. stenophyllum and B. komarovianum. In ESI-MS/MS spectra of SSs, [M-H](- )ions were subjected to the cleavage of glycosidic bonds and produced Y type ions, which can be used to elucidate the structures of saccharide chains and aglycones. Fragmentation of aglycones provided mass information about their major substitutions. For three structural types of SSs, type III can be easily identified by their fragmentation behaviors; while type I and II often occur as isomers and they can be discriminated by their typical UV absorption data. The only sugar ring-cross cleavage corresponding to 76 Da took place at a furanose sugar moiety. As a result, more than 75 SSs, including eight novel compounds, were identified or tentatively characterized based on their UV and mass spectra and retention times. The approach established here allows a comprehensive analysis of the SSs in the genus of Bupleurum and will be helpful for quality control of the crude materials and their related preparations.

An experimental device is constructed for measuring the density and liquidus temperature of molten fluorides by using the Archimedean and cooling curve methods respectively. Its operation is tested by measuring the density and liquidus temperature of NaCl salt. The accuracy of the liquidus temperature measurement is about +/- 1 K. The density of NaCl measured is in good agreement with the widely recognized data and the deviation is less than 0.2%. The liquidus temperature and density of a typical heat transfer fluoride LiF-NaF-KF (46.5-11.5-42mol%) are investigated.

The paper will describe a duoplasmatron ion source recently developed for solid materials such as As and P. The beam current of As + or P + on the target is above 100 μA; the beam current of As 2+ or P 2+ on the target exceeds 6 μA. One load in the crucible can last more than one hundred hours and there is no contamination at the cathode discharge area or the extractor area. With other materials such as Cd, S, Se, Zn, Te, Mg, etc. good results are obtained. Therefore, the performance of the implanter will be further improved.