Substrate-Controlled Regioselectivity Switchable [3 + 2] Annulations To Access Spirooxindole Skeletons.

The additive-free [3 + 2] annulation from isatins, amino acids with 2-styrylbenzoxazoles, was described, providing a series of functional and structurally complex 3,3'-pyrrolidinyl-spirooxindole derivatives containing four contiguous and two quaternary stereogenic centers in high yields (up to 95%) and excellent diastereoselectivities (up to >25:1 dr). Interestingly, the reaction exhibits switchable regioselectivity depending on the substrate of amino acids. With proline or thioproline as the substrate, the reaction afforded α-regioselective spirooxindole skeletons. In contrast, when piperidine acid is the substrate, the reaction provided γ-regioselective spirooxindole skeletons.

The PPAR-γ/SFRP5/Wnt/ß-catenin signal axis regulates the dexamethasone-induced osteoporosis.

BACKGROUND: The inhibition of glucocorticoid (GC) on osteoblastic differentiation of bone marrow stromal stem cells (BMSC) is an important pathway for GC to reduce bone formation. Recent studies implicated an important role of peroxisome proliferator-activated receptor-gamma (PPAR-γ) in GC-mediated cell proliferation and differentiation. Thus, our purpose is to investigate the role of PPAR-γ in regulating rat BMSC (rBMSC) osteoblastic differentiation. METHODS: The rBMSC treated with dexamethasone (Dex) was used to construct an in vitro cell model of GC-induced osteoporosis. The expressions of PPAR-γ, RUNX2, ALP, OPN and SFRP5 in cells were detected by RT-qPCR and western blot assays. Osteogenic differentiation of rBMSC was measured by Alizarin Red S (ARS) staining analysis. Lentivirus-delivered shRNA was used to knock down PPAR-γ or SFRP5, and lentivirus-delivered constructs were used to overexpress SFRP5 in rBMSC to verify the effect of PPAR-γ or SFRP5 on cell osteogenic differentiation. RESULTS: Dex significantly reduced rBMSC osteoblastic differentiation. The expression of PPAR-γ was enhanced in Dex treated rBMSC. PPAR-γ down-regulation improved Dex inhibition of rBMSC osteogenic differentiation. Moreover, PPAR-γ knockdown promoted protein levels of RUNX2, ALP, OPN and Dex-decreased rBMSC osteogenic differentiation. The expression of SFRP5 was reduced while Wnt and ß-catenin were increased in PPAR-γ knockdown and Dex treated rBMSC. Moreover, the up-regulation of SFRP5 reversed the osteogenic differentiation of rBMSC induced by PPAR-γ knockdown. CONCLUSION: These data indicated that in GC-induced osteoporosis, PPAR-γ/SFRP5 affects osteogenic differentiation by regulating the Wnt/ß-catenin signaling pathway.

Effects of Anthropogenic and Biogenic Volatile Organic Compounds on Los Angeles Air Quality.

Assessing the role of volatile organic compounds (VOCs) in production of ozone and secondary organic aerosol (SOA) is especially important in light of ongoing policy goals. Here, we estimated the ozone formation potential (OFP) and SOA formation potential (SOAP) of anthropogenic and biogenic VOC emissions to evaluate (1) anthropogenic VOCs and associated sectors that dominate OFP and SOAP and (2) the potential impacts of enhanced biogenic VOCs from urban greening programs on air quality in Los Angeles county. In the present-day scenario, ethylene had the largest OFP followed by m & p-xylene, toluene, propylene, and formaldehyde. The top five contributors to SOAP were toluene, mineral spirits, benzene, heptadecane, and hexadecane. Mobile and solvent sources were the dominant VOC sources for both OFP and SOAP. The potential increases in biogenic VOC emissions due to future urban greening had significant effects on urban air quality that offset the benefits of reducing anthropogenic VOC emissions. This study demonstrates that urban greening programs in Los Angeles county, and likely other cities as well, need to account for both anthropogenic and biogenic VOC contributions to secondary pollution, and greening cities should consider using vegetation types with low VOC emissions to avoid further degradation to urban air quality.

Apatinib Inhibits Angiogenesis in Intrahepatic Cholangiocarcinoma by Regulating the Vascular Endothelial Growth Factor Receptor-2/Signal Transducer and Activator of Transcription Factor 3/Hypoxia Inducible Factor 1 Subunit Alpha Signaling Axis.

INTRODUCTION: Intrahepatic cholangiocarcinoma (ICC), which is difficult to diagnose and is usually fatal due to its late clinical presentation and a lack of effective treatment, has risen over the past decades but without much improvement in prognosis. OBJECTIVE: The study aimed to investigate the role of apatinib that targets vascular endothelial growth factor receptor-2 (VEGFR2) in ICC. METHODS: MTT assays, cell scratch assays, and tube formation assays were used to assess the effect of apatinib on human ICC cell line (HuCCT-1) and RBE cells proliferation, migration, and angiogenic capacity, respectively. Expression of vascular endothelial growth factor (VEGF), VEGFR2, signal transducer and activator of transcription factor 3 (STAT3), pSTAT3, and hypoxia inducible factor 1 subunit alpha (HIF-1α) pathway proteins was assessed using Western blotting and mRNA expression analysis in HuCCT-1 was performed using RT-qPCR assays. The pcDNA 3.1(-)-VEGFR2 and pcDNA 3.1(-)-HIF-1α were transfected into HuCCT-1 and RBE cells using Lipofectamine 2,000 to obtain overexpressed HuCCT-1 and RBE cells. RESULTS: We found that apatinib-inhibited proliferation, migration, and angiogenesis of HuCCT-1 and RBE cells in vitro in a dose-dependent manner. We also proved that apatinib effectively inhibits angiogenesis in tumor cells by blocking the expression of VEGF and VEGFR2 in these cells. In addition, we demonstrated that apatinib regulates the expression of STAT3 phosphorylation by inhibiting VEGFR2. Finally, we showed that apatinib regulates ICC angiogenesis and HIF-1α/VEGF expression via STAT3. CONCLUSIONS: Based on the above findings, we conclude that apatinib inhibits HuCCT-1 and RBE cell proliferation, migration, and tumor angiogenesis by inhibiting the VEGFR2/STAT3/HIF-1α axis signaling pathway. Apatinib can be a promising drug for ICC-targeted molecular therapy.

Sevoflurane Postconditioning Reduces Hypoxia-Reoxygenation Injury in H9C2 Embryonic Rat Cardiomyocytes and Targets the STRADA Gene by Upregulating microRNA-107.

BACKGROUND Sevoflurane as a widely used inhalational general anesthetic that also has a cardioprotective role in hypoxia-reoxygenation (H/R) injury. This study aimed to investigate the effects of microRNA-107 (miR-107) on sevoflurane postconditioning (SpostC) in H9C2 embryonic rat cardiomyocytes and to use bioinformatics analysis to identify the molecular basis of cardioprotection from sevoflurane in human cardiac tissue. MATERIAL AND METHODS The STRADA gene was identified from the Gene Expression Omnibus (GEO) database. H9C2 embryonic rat cardiomyocytes were cultured with sevoflurane. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to measure the mRNA expression and protein expression of STRADA and miR-107 in H9C2 cells. TargetScanHuman version 7.2 was used to identify the target gene of miR-107 and to predict the STRADA 3'-UTR binding site of miR-107. The dual-luciferase reporter assay measured the relative luciferase activity. The cell proliferation rate and cell apoptosis were measured using the MTT assay and flow cytometry, respectively. RESULTS H/R injury in H9C2 cells following SpostC resulted in increased expression of miR-107 and reduced expression of STRADA. Specific binding of miR-107 was identified to STRADA 3'-UTR. Upregulation of the miR-107 in SpostC H/R injured H9C2 cells promoted cell proliferation, reduced cell apoptosis, and downregulating the protein expression of caspase-3. STRADA overexpression reduced the effects of a miR-107 mimic on SpostC. CONCLUSIONS SpostC reduced H/R injury in H9C2 embryonic rat cardiomyocytes by targeting the STRADA gene and by upregulating the expression of microRNA-107.

O-GlcNAcylation destabilizes the active tetrameric PKM2 to promote the Warburg effect.

The Warburg effect, characterized by increased glucose uptake and lactate production, is a well-known universal across cancer cells and other proliferating cells. PKM2, a splice isoform of the pyruvate kinase (PK) specifically expressed in these cells, serves as a major regulator of this metabolic reprogramming with an adjustable activity subjected to numerous allosteric effectors and posttranslational modifications. Here, we have identified a posttranslational modification on PKM2, O-GlcNAcylation, which specifically targets Thr405 and Ser406, residues of the region encoded by the alternatively spliced exon 10 in cancer cells. We show that PKM2 O-GlcNAcylation is up-regulated in various types of human tumor cells and patient tumor tissues. The modification destabilized the active tetrameric PKM2, reduced PK activity, and led to nuclear translocation of PKM2. We also observed that the modification was associated with an increased glucose consumption and lactate production and enhanced level of lipid and DNA synthesis, indicating that O-GlcNAcylation promotes the Warburg effect. In vivo experiments showed that blocking PKM2 O-GlcNAcylation attenuated tumor growth. Thus, we demonstrate that O-GlcNAcylation is a regulatory mechanism for PKM2 in cancer cells and serves as a bridge between PKM2 and metabolic reprogramming typical of the Warburg effect.

Identification of consensus sequence from matrix attachment regions and functional analysis of its activity in stably transfected Chinese hamster ovary cells.

Matrix attachment regions (MARs) can enhance transgene expression levels and maintain stability. However, the consensus sequence from MARs and its functional analysis remains to be examined. Here, we assessed a possible consensus sequence from MARs and assessed its activity in stably transfected Chinese hamster ovary (CHO) cells. First, we analyzed the effects of 10 MARs on transfected CHO cells and then analyzed the consensus motifs from these MARs using a bioinformatics method. The consensus sequence was synthesized and cloned upstream or downstream of the eukaryotic vector. The constructs were transfected into CHO cells and the expression levels and stability of enhanced green fluorescent protein were detected by flow cytometry. The results indicated that eight of the ten MARs increased transgene expression in transfected CHO cells. Three consensus motifs were found after bioinformatics analyses. The consensus sequence tandemly enhanced transgene expression when it was inserted into the eukaryotic expression vector; the effect of the addition upstream was stronger than that downstream. Thus, we found a MAR consensus sequence that may regulate the MAR-mediated increase in transgene expression.

[Determination of arsenic speciation in 17 commonly used traditional Chinese herbal medicines by HPLC-ICP-MS].

The element speciation analysis for heavy metals in herbal medicines is still in the beginning stage. In this study,the total amount of arsenic( As) in 103 batches of 17 commonly used Chinese medicines( including 16 plant medicines and 1 medicinal fungus) was detected by inductively coupled plasma mass spectrometry( ICP-MS). Furthermore,based on HPLC-ICP-MS,the simultaneous detection methods of six As speciation kinds in traditional Chinese medicines were established. An AS7 anion exchange column was selected and the As forms in 17 traditional Chinese medicines was systematically analyzed. The results showed that the method of pretreatment of medicinal materials by microwave digestion and the detection of total amount of As by ICP-MS was stable and reliable. As for the speciation analysis of As,the high-speed ultrasonic extraction method was adopted,and it showed that the linear relationship of the six As speciation was satisfied with the correlation coefficient R2>0. 999 9. The LOQ of six kinds of As speciation were 0. 20,0. 10,0. 15,0. 10,0. 25,0. 10 µg·L~(-1) for arsenic betaine( As B),arsenious acid [As( Ⅲ) ],dimethyl arsenic( DMA),arsenic choline( As C),monomethyl arsenic( MMA),arsenic acid[As( Ⅴ) ],respectively. The recoveries were between 84. 24% and 121. 5%,and the relative standard deviations were 2. 7% to 11%. Among the 103 batches of medicinal materials,only one batch of sample As exceeded the Chinese Pharmacopoeia limit standard; As( Ⅲ) and As( Ⅴ) had high detection rate in 103 batches of Chinese herbal medicines,within which As( Ⅴ) was the main detected form,and inorganic As accounted for the ratio reached 80. 90%-98. 73%; some samples detected DMA,MMA and As B,As C was not detected in any batch. This study established an analytical method suitable for the speciation of As in Chinese herbal medicines,and provided basic data for As residual residue in Chinese herbal medicines,which can provide important reference for the risk assessment and quality standards.

The human PMR1 endonuclease stimulates cell motility by down regulating miR-200 family microRNAs.

The motility of MCF-7 cells increases following expression of a human PMR1 transgene and the current study sought to identify the molecular basis for this phenotypic change. Ensemble and single cell analyses show increased motility is dependent on the endonuclease activity of hPMR1, and cells expressing active but not inactive hPMR1 invade extracellular matrix. Nanostring profiling identified 14 microRNAs that are downregulated by hPMR1, including all five members of the miR-200 family and others that also regulate invasive growth. miR-200 levels increase following hPMR1 knockdown, and changes in miR-200 family microRNAs were matched by corresponding changes in miR-200 targets and reporter expression. PMR1 preferentially cleaves between UG dinucleotides within a consensus YUGR element when present in the unpaired loop of a stem-loop structure. This motif is present in the apical loop of precursors to most of the downregulated microRNAs, and hPMR1 targeting of pre-miRs was confirmed by their loss following induced expression and increase following hPMR1 knockdown. Introduction of miR-200c into hPMR1-expressing cells reduced motility and miR-200 target gene expression, confirming hPMR1 acts upstream of Dicer processing. These findings identify a new role for hPMR1 in the post-transcriptional regulation of microRNAs in breast cancer cells.

[Estimation of bioaccessibility and risk assessment of heavy metals in decoction pieces of Bupleuri Radix].

This project was launched to study on the overall residual status of heavy metals of comprehensive understanding in decoction pieces of Bupleuri Radix (DPBR) from different habitats and risk assessment. In this study, inductively coupled plasma mass spectrometry was used to determine the heavy metals of 30 batches of Bupleuri Radix in different producing areas. Simulated gastrointestinal fluid method was used to determine the dissolution rate of heavy metals in the simulated gastrointestinal fluid and the average daily intake Average Daily Dose (ADD) and Hazard Quotient (HQ) index were used to assess the risk of heavy metals in DPBR. The results showed that the contents of copper (Cu), lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) in the 30 batches of DPBR didn't exceed the limit of Chinese Pharmacopeia, however, the chromium (Cr) in DPBR exeeded the limit set by NSF in USA and the limit for herbal ingredients in Canada. The mean bioaccessible heavy metal concentrations decreased from Cu (5.27 mg·kg⁻¹)>Cr (4.67 mg·kg⁻¹)>As (0.18 mg·kg⁻¹)>Pb (0.12 mg·kg⁻¹)>Cd (0.06 mg·kg⁻¹), and Hg was not detected in this test. In addition, cumulative non-carcinogenic health risks (HI) for adults and children were 0.799 and 0.714, respectively. Both HI values in adults and children for combined trace element and heavy metal element exposures were below the value of 1 (HI<1), indicating very low carcinogenic health risk. Heavy metals toxicity in herbal medicines and its health risk to humans would be overestimated when assessed only by the total concentrations without considering the bioaccessibility. Therefore, bioaccessibility has great significance for evaluating the human health risks induced by heavy metals.

[Research progress of chromium and its speciation analysis].

Chromium has been discovered for more than two hundred years, and it has advantages of wear-resisting, high temperature, corrosion resistance and so on. Chromium has been widely used in industrial production and received extensive attention in China and abroad. Detailed limit standards have been set for chromium in food and fishery product, and chromium can also be enriched in many traditional Chinese medicines. Besides, the toxicities of different chromium speciation are quite different, and thus morphological analysis is necessary. However, the transformation or migration is easily happened among different speciation which brings difficulties to research and analysis. This article summarizes the research status of chromium and its aims to provide reference for scientific research and pollution prevention of chromium.

A three-dimensional model of a group II intron RNA and its interaction with the intron-encoded reverse transcriptase.

Group II introns are self-splicing ribozymes believed to be the ancestors of spliceosomal introns. Many group II introns encode reverse transcriptases that promote both RNA splicing and intron mobility to new genomic sites. Here we used a circular permutation and crosslinking method to establish 16 intramolecular distance relationships within the mobile Lactococcus lactis Ll.LtrB-DeltaORF intron. Using these new constraints together with 13 established tertiary interactions and eight published crosslinks, we modeled a complete three-dimensional structure of the intron. We also used the circular permutation strategy to map RNA-protein interaction sites through fluorescence quenching and crosslinking assays. Our model provides a comprehensive structural framework for understanding the function of group II ribozymes, their natural structural variations, and the mechanisms by which the intron-encoded protein promotes RNA splicing and intron mobility. The model also suggests an arrangement of active site elements that may be conserved in the spliceosome.

Exogenous GA3 Application Enhances Xylem Development and Induces the Expression of Secondary Wall Biosynthesis Related Genes in Betula platyphylla.

Gibberellin (GA) is a key signal molecule inducing differentiation of tracheary elements, fibers, and xylogenesis. However the molecular mechanisms underlying the effect of GA on xylem elongation and secondary wall development in tree species remain to be determined. In this study, Betula platyphylla (birch) seeds were treated with 300 ppm GA3 and/or 300 ppm paclobutrazol (PAC), seed germination was recorded, and transverse sections of hypocotyls were stained with toluidine blue; the two-month-old seedlings were treated with 50 µM GA3 and/or 50 µM PAC, transverse sections of seedling stems were stained using phloroglucinol-HCl, and secondary wall biosynthesis related genes expression was analyzed by real-time quantitative PCR. Results indicated that germination percentage, energy and time of seeds, hypocotyl height and seedling fresh weight were enhanced by GA3, and reduced by PAC; the xylem development was wider in GA3-treated plants than in the control; the expression of NAC and MYB transcription factors, CESA, PAL, and GA oxidase was up-regulated during GA3 treatment, suggesting their role in GA3-induced xylem development in the birch. Our results suggest that GA3 induces the expression of secondary wall biosynthesis related genes to trigger xylogenesis in the birch plants.

[Informed consent right of the appraised individuals in forensic clinical examination].

Informed consent right is not just for basic ethical consideration, but is important for protecting patient's right by law, which is expressed through informed consent contract. The appraised individuals of forensic clinical examination have the similar legal status as the patients in medical system. However, the law does not require informed consent right for the appraised individuals. I recommend giving certain informed consent right to the appraised individuals in the forensic clinical examination. Under the contracted relationship with the institution, the appraised individuals could participate in the examination process, know the necessary information, and make a selected consent on the examination results, which can assure the justice and fairness of judicial examination procedure.

Degradation of cardiac myosin light chain kinase by matrix metalloproteinase-2 contributes to myocardial contractile dysfunction during ischemia/reperfusion.

Although ischemia/reperfusion (I/R)-induced myocardial contractile dysfunction is associated with a prominent decrease in myofilament Ca(2+) sensitivity, the underlying mechanisms have not yet been fully clarified. Phosphorylation of ventricular myosin light chain 2 (MLC-2v) facilitates actin-myosin interactions and enhances contractility, however, its level and regulation by cardiac MLC kinase (cMLCK) and cMLC phosphatase (cMLCP) in I/R hearts are debatable. In this study, the levels and/or effects of MLC-2v phosphorylation, cMLCK, cMLCP, and proteases during I/R were determined. Global myocardial I/R-suppressed cardiac performance in isolated rat hearts was concomitant with decreases of MLC-2v phosphorylation, myofibrillar Ca(2+)-stimulated ATPase activity, and cMLCK content, but not cMLCP proteins. Consistently, simulated I/R in isolated cardiomyocytes inhibited cell shortening, Ca(2+) transients, MLC-2v phosphorylation, and myofilament sensitivity to Ca(2+). These observations were reversed by cMLCK overexpression, while the specific cMLCK knockdown by short hairpin RNA (shRNA) had the opposite effect. Moreover, the inhibition of matrix metalloproteinase-2 (MMP-2, a zinc-dependent endopeptidase) reversed IR-decreased cMLCK, MLC-2v phosphorylation, myofibrillar Ca(2+)-stimulated ATPase activity, myocardial contractile function, and myofilament sensitivity to Ca(2+), while the inhibition or knockdown of cMLCK by ML-9 or specific shRNA abolished MMP-2 inhibition-induced cardioprotection. Finally, the co-localization in cardiomyocytes and interaction in vivo of MMP-2 and cMLCK were observed. Purified recombinant rat cMLCK was concentration- and time-dependently degraded by rat MMP-2 in vitro, and this was prevented by the inhibition of MMP-2. These findings reveal that the I/R-activated MMP-2 leads to the degradation of cMLCK, resulting in a reduction of MLC-2v phosphorylation, and myofibrillar Ca(2+)-stimulated ATPase activity, which subsequently suppresses myocardial contractile function through a decrease of myofilament Ca(2+) sensitivity.

Identification of the human PMR1 mRNA endonuclease as an alternatively processed product of the gene for peroxidasin-like protein.

The PMR1 endonuclease was discovered in Xenopus liver and identified as a member of the large and diverse peroxidase gene family. The peroxidase genes arose from multiple duplication and rearrangement events, and their high degree of sequence similarity confounded attempts to identify human PMR1. The functioning of PMR1 in mRNA decay depends on the phosphorylation of a tyrosine in the C-terminal polysome targeting domain by c-Src. The sequences of regions that are required for c-Src binding and phosphorylation of Xenopus PMR1 were used to inform a bioinformatics search that identified two related genes as potential candidates for human PMR1: peroxidasin homolog (PXDN) and peroxidasin homolog-like (PXDNL) protein. Although each of these genes is predicted to encode a large, multidomain membrane-bound peroxidase, alternative splicing of PXDNL pre-mRNA yields a transcript whose predicted product is a 57-kDa protein with 42% sequence identity to Xenopus PMR1. Results presented here confirm the existence of the predicted 57-kDa protein, show this is the only form of PXDNL detected in any of the human cell lines examined, and confirm its identity as human PMR1. Like the Xenopus protein, human PMR1 binds to c-Src, is tyrosine phosphorylated, sediments on polysomes, and catalyzes the selective decay of a PMR1 substrate mRNA. Importantly, the expression of human PMR1 stimulates cell motility in a manner similar to that of the Xenopus PMR1 expressed in human cells, thus providing definitive evidence linking endonuclease decay to the regulation of cell motility.

Emerging investigator series: secondary organic aerosol formation from photooxidation of acyclic terpenes in an oxidation flow reactor.

One major challenge in predicting secondary organic aerosol (SOA) formation in the atmosphere is incomplete representation of biogenic volatile organic compounds (BVOCs) emitted from plants, particularly those that are emitted as a result of stress - a condition that is becoming more frequent in a rapidly changing climate. One of the most common types of BVOCs emitted by plants in response to environmental stress are acyclic terpenes. In this work, SOA is generated from the photooxidation of acyclic terpenes in an oxidation flow reactor and compared to SOA production from a reference cyclic terpene - α-pinene. The acyclic terpenes used as SOA precursors included ß-myrcene, ß-ocimene, and linalool. Results showed that oxidation of all acyclic terpenes had lower SOA yields measured after 4 days photochemical age, in comparison to α-pinene. However, there was also evidence that the condensed organic products that formed, while a smaller amount overall, had a higher oligomeric content. In particular, ß-ocimene SOA had higher oligomeric content than all the other chemical systems studied. SOA composition data from ultra-high performance liquid chromatography with electrospray ionization mass spectrometry (UHPLC-ESI-MS) was combined with mechanistic modeling using the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to explore chemical mechanisms that could lead to this oligomer formation. Calculations based on composition data suggested that ß-ocimene SOA was more viscous with a higher glass transition temperature than other SOA generated from acyclic terpene oxidation. This was attributed to a higher oligomeric content compared to other SOA systems studied. These results contribute to novel chemical insights about SOA formation from acyclic terpenes and relevant chemistry processes, highlighting the importance of improving underrepresented biogenic SOA formation in chemical transport models.

Limonene Enantiomeric Ratios from Anthropogenic and Biogenic Emission Sources.

Emissions from volatile chemical products (VCPs) have been identified as contributors to air quality degradation in urban areas. Limonene can be a tracer compound for VCPs containing fragrances in densely populated regions, but limonene is also emitted from conifers that are planted in urban areas. This creates challenges for using limonene to estimate VCP emissions. In this study, the -/+ enantiomeric ratios of limonene from VCP and conifer emission sources were quantified to evaluate if this measurement could be used to aid in source apportionment and emission inventory development. Samples were analyzed using a gas chromatograph equipped with a chiral column and mass spectrometry. The results demonstrate that limonene exhibits distinct enantiomeric ratios when sourced from VCPs versus conifers. (+)-Limonene was dominant in VCP sources (>97%), which was not universally true for conifer sources. The results were compared to those of air samples collected outside at two locations and indoors. The levels of (-)-limonene in outdoor air in Irvine and Portland and in indoor air were 50%, 22%, and 4%, respectively. This suggests outdoor limonene had both VCP and plant emission sources while indoor air was dominated by VCP sources. This study demonstrates the potential utility of enantiomeric analysis for improving VCP emission estimates in urban areas.

Rehydration effect of qingshu buye decoction on exercise and high temperature-induced dehydration.

OBJECTIVE: The aim of this study was to conduct a comprehensive evaluation of the rehydration efficacy of QSBYD and elucidate its potential underlying mechanism. DESIGN: 38 participants were randomly assigned to receive either QSBYD or placebo before and after exercise and heat-induced dehydration. Hydration indicators were measured over time. Blood tests assessed cellular anaerobic respiration metabolites, serum inflammatory markers, and coagulation markers. Perceptual measures of thirst, fatigue, and muscular soreness were also taken. RESULTS: QSBYD consumption resulted in lower urine volume (Control vs. QSBYD: 260.83 ± 167.99 ml vs. 187.78 ± 141.34 ml) and smaller decrease in percentage of nude body weight change from baseline (Control vs. QSBYD: -0.52 ± 0.89% vs. -0.07 ± 0.52%). Although no significant differences in urine specific gravity, QSBYD resulted in reduced urine volume at 120 min, suggesting improved fluid retention. Furthermore, QSBYD resulted in lower levels of IL-1ß (Control vs. QSBYD: 2.40 ± 0.68 vs. 1.33 ± 0.66 pg/mL), suggesting QSBYD may provide benefits beyond hydration. CONCLUSION: Further investigation into the underlying mechanisms and long-term effects of QSBYD on hydration is warranted. QSBYD may be an effective alternative to commercial sports drinks in mitigating dehydration effects.

Identification of lignans as ATP citrate lyase (ACLY) inhibitors from the roots of Pouzolzia zeylanica.

A new lignan, named pouzolignan P (1), together with 14 known ones (2 - 15) were isolated from the roots of Pouzolzia zeylanica (L.) Benn. Their structures were deduced based on the detailed spectroscopic analysis. All the isolates were evaluated for their inhibitory activities toward the ATP citrate lyase (ACLY). Among them, four lignans, isopouzolignan K (3), gnemontanins E (5), gnetuhainin I (6), and styraxlignolide D (15) showed excellent ACLY inhibitory effect with IC50 values of 9.06, 0.59, 2.63, and 7.62 µM, respectively. These compounds were further evaluated for their cholesterol-lowing effects on ox-LDL-induced high-cholesterol HepG2 cells. Compound 15 emerges as the most potent ACLY inhibitor, which significantly decreased the TC level in a dose-dependent manner. In addition, molecular docking simulations elucidated that 15 formed a strong hydrogen-bond interaction with Glu599 of ACLY, which was an important site responsible for the enzyme catalytic activity.