Structural insights into adhesion GPCR ADGRL3 activation and Gq, Gs, Gi, and G12 coupling.

Adhesion G-protein-coupled receptors (aGPCRs) play key roles in a diversity of physiologies. A hallmark of aGPCR activation is the removal of the inhibitory GAIN domain and the dipping of the cleaved stalk peptide into the ligand-binding pocket of receptors; however, the detailed mechanism remains obscure. Here, we present cryoelectron microscopy (cryo-EM) structures of ADGRL3 in complex with Gq, Gs, Gi, and G12. The structures reveal unique ligand-engaging mode, distinctive activation conformation, and key mechanisms of aGPCR activation. The structures also reveal the uncharted structural information of GPCR/G12 coupling. A comparison of Gq, Gs, Gi, and G12 engagements with ADGRL3 reveals the key determinant of G-protein coupling on the far end of αH5 of Gα. A detailed analysis of the engagements allows us to design mutations that specifically enhance one pathway over others. Taken together, our study lays the groundwork for understanding aGPCR activation and G-protein-coupling selectivity.

Over 104 -fold amplified upconversion luminescence of lanthanide nanocrystals through optical oscillator-like system.

Recently, lanthanide (Ln) luminescent nanocrystals have attracted increasing attention in various fields such as biomedical imaging, lasers, and anticounterfeiting. However, due to the forbidden 4f-4f transition of lanthanide ions, the absorption cross-section and luminescence brightness of lanthanide nanocrystals are limited. To address the challenge, we constructed an optical oscillator-like system to repeatedly simulate lanthanide nanocrystals to enhance the absorption efficiency of lanthanide ions on excitation photons. In this optical system, the upconversion luminescence (UCL) of Tm3+ emission of ~450 nm excited by a 980 nm laser can be amplified by a factor beyond 104 . The corresponding downshifting luminescence of Tm3+ at 1460 nm was enhanced by three orders of magnitude. We also demonstrated that the significant luminescence enhancement in the designed optical oscillator-like system was general for various lanthanide nanocrystals including NaYF4 :Yb3+ /Ln3+ , NaErF4 @NaYF4 and NaYF4 :Yb3+ /Ln3+ @NaYF4 :Yb3+ @NaYF4 (Ln = Er, Tm, Ho) regardless of the wavelengths of excitation sources (808 and 980 nm). The mechanism study revealed that both elevated laser power in the optical system and multiple excitations on lanthanide nanocrystals were the main reason for the luminescence amplification. Our findings may benefit the future development of low-threshold upconversion and downshifting luminescence of lanthanide nanocrystals and expand their applications.

Relationship between caffeine intake and thyroid function: results from NHANES 2007-2012.

BACKGROUND: Moderate caffeine intake decreases the risk of metabolic disorders and all-cause mortality, and the mechanism may be related to its ergogenic actions. Thyroid hormones are vital in metabolic homeostasis; however, their association with caffeine intake has rarely been explored. OBJECTIVE: To investigate the association between caffeine intake and thyroid function. METHODS: We collected data on demographic background, medical conditions, dietary intake, and thyroid function from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Subgroups were classified using two-step cluster analysis, with sex, age, body mass index (BMI), hyperglycemia, hypertension, and cardio-cerebral vascular disease (CVD) being used for clustering. Restrictive cubic spline analysis was employed to investigate potential nonlinear correlations, and multivariable linear regression was used to evaluate the association between caffeine consumption and thyroid function. RESULTS: A total of 2,582 participants were included, and three subgroups with different metabolic features were clustered. In the most metabolically unhealthy group, with the oldest age, highest BMI, and more cases of hypertension, hyperglycemia, and CVD, there was a nonlinear relationship between caffeine intake and serum thyroid stimulating hormone (TSH) level. After adjusting for age, sex, race, drinking, smoking, medical conditions, and micronutrient and macronutrient intake, caffeine intake of less than 9.97 mg/d was positively associated with serum TSH (p = 0.035, standardized ß = 0.155); however, moderate caffeine consumption (9.97-264.97 mg/d) indicated a negative association (p = 0.001, standardized ß = - 0.152). CONCLUSIONS: Caffeine consumption had a nonlinear relationship with serum TSH in people with metabolic disorders, and moderate caffeine intake (9.97 ~ 264.97 mg/d) was positively associated with serum TSH.

S-nitrosylation of EMMPRIN influences the migration of HSCs and MMP activity in liver fibrosis.

The mechanism of extracellular matrix metalloproteinase inducer (EMMPRIN) in the regulation of liver fibrosis has not been clarified. This study aims to investigate the role of EMMPRIN S-nitrosylation (SNO) in the regulation of hepatic stellate cell (HSC) migration and matrix metalloproteinase (MMP) activities in liver fibrosis. The results from the tissue microarrays and rat/mouse liver tissues suggest that EMMPRIN mRNA and protein levels in the fibrotic livers are lower than those in the corresponding normal control livers, but higher SNO level of EMMPRIN in fibrotic liver area was shown by immunohistochemistry, immunofluorescence staining, and biotin-switch assay conversely in vivo. Primary EMMPRIN comes from hepatocytes and liver sinus epithelial cells (LSECs) rather than quiescent HSCs. To mimic the uptake of extrinsic EMMPRIN, supernatants from mouse primary hepatocytes/293 cells transfected with EMMPRIN wild-type plasmids (WT) and EMMPRIN SNO site (cysteine 87) mutation plasmids (MUT) were collected and added to JS-1/LX2 cell medium. The MUT EMMPRIN diminishes SNO successfully, enhances the activities of MMP2 and MMP9, and subsequently increases HSC migration. In conclusion, SNO of EMMPRIN influences HSC migration and MMP activities in liver fibrosis. This finding may shed light on the possible regulatory mechanism of MMPs in ECM accumulation in liver fibrosis.

Rational Design of NIR-II AIEgens with Ultrahigh Quantum Yields for Photo- and Chemiluminescence Imaging.

Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) using small-molecule dyes has high potential for clinical use. However, many NIR-II dyes suffer from the emission quenching effect and extremely low quantum yields (QYs) in the practical usage forms. The AIE strategy has been successfully utilized to develop NIR-II dyes with donor-acceptor (D-A) structures with acceptable QYs in the aggregate state, but there is still large room for QY improvement. Here, we rationally designed a NIR-II emissive dye named TPE-BBT and its derivative (TPEO-BBT) by changing the electron-donating triphenylamine unit to tetraphenylethylene (TPE). Their nanoparticles exhibited ultrahigh relative QYs of 31.5% and 23.9% in water, respectively. By using an integrating sphere, the absolute QY of TPE-BBT nanoparticles was measured to be 1.8% in water. Its crystals showed an absolute QY of 10.4%, which is the highest value among organic small molecules reported so far. The optimized D-A interaction and the higher rigidity of TPE-BBT in the aggregate state are believed to be the two key factors for its ultrahigh QY. Finally, we utilized TPE-BBT for NIR-II photoluminescence (PL) and chemiluminescence (CL) bioimaging through successive CL resonance energy transfer and Förster resonance energy transfer processes. The ultrahigh QY of TPE-BBT realized an excellent PL imaging quality in mouse blood vessels and an excellent CL imaging quality in the local arthrosis inflammation in mice with a high signal-to-background ratio of 130. Thus, the design strategy presented here brings new possibilities for the development of bright NIR-II dyes and NIR-II bioimaging technologies.

Exploring the impact of under-reported cases on the COVID-19 spatiotemporal distributions using healthcare workers infection data.

A timely understanding of the spatiotemporal pattern and development trend of COVID-19 is critical for timely prevention and control. However, the under-reporting of casesis widespread in fields associated with public health. It is also possible to draw biased inferences and formulate inappropriate prevention and control policies if the phenomenon of under-reporting is not taken into account. Therefore, in this paper, a novel framework was proposed to explore the impact of under-reporting on COVID-19 spatiotemporal distributions, and empirical analysis was carried out using infection data of healthcare workers in Wuhan and Hubei (excluding Wuhan). The results show that (1) the lognormal distribution was the most suitable to describe the evolution of epidemic with time; (2) the estimated peak infection time of the reported cases lagged the peak infection time of the healthcare worker cases, and the estimated infection time interval of the reported cases was smaller than that of the healthcare worker cases. (3) The impact of under-reporting cases on the early stages of the pandemic was greater than that on its later stages, and the impact on the early onset area was greater than that on the late onset area. (4) Although the number of reported cases was lower than the actual number of cases, a high spatial correlation existed between the cumulatively reported cases and healthcare worker cases. The proposed framework of this study is highly extensible, and relevant researchers can use data sources from other counties to carry out similar research.

Luminescence Lifetime Imaging Based on Lanthanide Nanoparticles.

Luminescence lifetime imaging has exhibited significant advantages over traditional optical imaging in terms of precise quantification detection because of the intrinsic stability of luminescence lifetimes. Recently, great emphasis has been put on the exploration of lanthanide-doped nanoparticles (LnNPs) with long-lived luminescence. The long luminescence lifetime of LnNPs not only makes it easier to filter out background signals during imaging, but also provides a wide range of tunable lifetime. Here, we introduce the luminescence mechanisms of LnNPs, the key strategies for luminescence lifetime modulation, data acquisition methods, and several cutting-edge applications in lifetime imaging systems. Then we describe several prospects to inspire efforts for improving technologies and extending applications of luminescence lifetime imaging.

Transcriptomic responses to drought stress in Polygonatum kingianum tuber.

BACKGROUND: Polygonatum kingianum Coll. et Hemsl. is an important plant in Traditional Chinese Medicine. The extracts from its tubers are rich in polysaccharides and other metabolites such as saponins. It is a well-known concept that growing medicinal plants in semi-arid (or drought stress) increases their natural compounds concentrations. This study was conducted to explore the morpho-physiological responses of P. kingianum plants and transcriptomic signatures of P. kingianum tubers exposed to mild, moderate, and severe drought and rewatering. RESULTS: The stress effects on the morpho-physiological parameters were dependent on the intensity of the drought stress. The leaf area, relative water content, chlorophyll content, and shoot fresh weight decreased whereas electrolyte leakage increased with increase in drought stress intensity. A total of 53,081 unigenes were obtained; 59% of which were annotated. We observed that 1352 and 350 core genes were differentially expressed in drought and rewatering, respectively. Drought stress driven differentially expressed genes (DEGs) were enriched in phenylpropanoid biosynthesis, flavonoid biosynthesis, starch and sucrose metabolism, and stilbenoid diarylheptanoid and gingerol biosynthesis, and carotenoid biosynthesis pathways. Pathways such as plant-pathogen interaction and galactose metabolism were differentially regulated between severe drought and rewatering. Drought reduced the expression of lignin, gingerol, and flavonoid biosynthesis related genes and rewatering recovered the tubers from stress by increasing the expression of the genes. Increased expression of carotenoid biosynthesis pathway related genes under drought suggested their important role in stress endurance. An increase in starch and sucrose biosynthesis was evident from transcriptomic changes under drought stress. Rewatering recovered the drought affected tubers as evident from the contrasting expression profiles of genes related to these pathways. P. kingianum tuber experiences an increased biosynthesis of sucrose, starch, and carotenoid under drought stress. Drought decreases the flavonoids, phenylpropanoids, gingerol, and lignin biosynthesis. These changes can be reversed by rewatering the P. kingianum plants. CONCLUSIONS: These results provide a transcriptome resource for P. kingianum and expands the knowledge on the effect of drought and rewatering on important pathways. This study also provides a large number of candidate genes that could be manipulated for drought stress tolerance and managing the polysaccharide and secondary metabolites' contents in P. kingianum.

High-Fidelity NIR-II Multiplexed Lifetime Bioimaging with Bright Double Interfaced Lanthanide Nanoparticles.

Fluorescence lifetime imaging provides more possibility of in vivo multiplexing in second near infrared (NIR-II) window. However, it still faces the obstacle that fluorescent probes with differentiable lifetime often exhibit quite different fluorescence intensity, especially the short lifetime usually accompanies with a weak fluorescence intensity, resulting in the difficulty for simultaneously decoding multiplexed lifetime information due to the interference of background noise. To facilitate high-fidelity lifetime multiplexed imaging, we developed a series of Er3+ doped double interface fluorescent nanoprobes (Er-DINPs): α-NaYF4 @NaErF4 : Ce@NaYbF4 @NaErF4 : Ce@NaYF4 with strong fluorescence intensity and easily distinguishable fluorescence lifetime. Both in vitro and in vivo experimental results confirmed the advantage of these probes with comparable fluorescence intensity for high-fidelity multiplexed lifetime bioimaging.

Detection of Indoor High-Density Crowds via Wi-Fi Tracking Data.

Accurate detection of locations of indoor high-density crowds is crucial for early warning and emergency rescue during indoor safety accidents. The spatial structure of indoor environments is more complicated than outdoor environments. The locations of indoor high-density crowds are more likely to be the sites of security accidents. Existing detection methods for high-density crowd locations mostly focus on outdoor environments, and relatively few detection methods exist for indoor environments. This study proposes a novel detection framework for high-density indoor crowd locations termed IndoorSRC (Simplification-Reconstruction-Cluster). In this paper, a novel indoor spatiotemporal clustering algorithm called Indoor-STAGNES is proposed to detect the indoor trajectory stay points to simplify indoor movement trajectory. Then, we propose use of a Kalman filter algorithm to reconstruct the indoor trajectory and properly align and resample the data. Finally, an indoor spatiotemporal density clustering algorithm called Indoor-STOPTICS is proposed to detect the locations of high-density crowds in the indoor environment from the reconstructed trajectory. Extensive experiments were conducted using indoor Wi-Fi positioning datasets collected from a shopping mall. The results show that the IndoorSRC framework evidently outperforms the existing baseline method in terms of detection performance.

Precise In†Vivo Inflammation Imaging Using In†Situ Responsive Cross-linking of Glutathione-Modified Ultra-Small NIR-II Lanthanide Nanoparticles.

To improve the bioimaging signal-to-noise ratio (SNR), long-term imaging capability, and decrease the potential biotoxicity, an in vivo cross-linking strategy was developed by using sub-10 nm, glutathione-modified, lanthanide nanoprobes. After administration, the nanoprobes cross-link in response to reactive oxygen species (ROS) at the inflamed area and enable the quick imaging of ROS in the second near-infrared (NIR-II) window. These nanoprobes could be rapidly excreted due to their ultra-small size. This strategy may also be applied to other ultra-small contrast agents for the precise bioimaging by in situ lesion cross-linking.

Identification of Potential Biomarkers from Aconitum carmichaelii, a Traditional Chinese Medicine, Using a Metabolomic Approach.

Despite their well-known toxicity, Aconitum species are important traditional medicines worldwide. Aconitum carmichaelii, known in Chinese as (fuzi), is an officially recognized traditional Chinese medicine with characteristic analgesic and anti-inflammatory activities, whose principal pharmacological ingredients are considered as aconitine-type diterpene alkaloids. Notwithstanding the long-recorded use of A. carmichaelii in traditional Chinese medicine, no single-entity aconitum alkaloid drug has been developed for clinical use. UPLC-Q-TOF-MS was used to investigate the marker compounds that can be used to differentiate A. carmichaelii from seven other Aconitum species collected in Yunnan Province. Nontargeted principle component analysis scores plots found that all the tested Aconitum species clustered into three distinct groups, and A. carmichaelii was significantly different chemically than the other seven species. Furthermore, the primary and lateral roots of A. carmichaelii also showed significant differences. Using orthogonal partial least squares discriminate analysis analysis, eight marker compounds were identified, including 14-acetylkarakoline, aconitine, carmichaeline, fuziline, hypaconitine, mesaconitine, neoline, and talatisamine. Four of these aconitum alkaloids, fuziline, hypaconitine, mesaconitine, and neoline, showed significant analgesic activity in a dose-dependent manner compared to the negative and positive controls. However, hypaconitine, mesaconitine, and neoline exhibited significant acute toxicity activity, while fuziline showed no acute toxicity in mice, suggesting the relative safety of this alkaloid. This study provides a good example of how to differentiate an authentic medicinal plant from common adulterants using a metabolomics approach, and to identify compounds that may be developed into new drugs.

An Adaptive Method for Switching between Pedestrian/Car Indoor Positioning Algorithms based on Multilayer Time Sequences.

Pedestrian dead reckoning (PDR) positioning algorithms can be used to obtain a target's location only for movement with step features and not for driving, for which the trilateral Bluetooth indoor positioning method can be used. In this study, to obtain the precise locations of different states (pedestrian/car) using the corresponding positioning algorithms, we propose an adaptive method for switching between the PDR and car indoor positioning algorithms based on multilayer time sequences (MTSs). MTSs, which consider the behavior context, comprise two main aspects: filtering of noisy data in small-scale time sequences and using a state chain to reduce the time delay of algorithm switching in large-scale time sequences. The proposed method can be expected to realize the recognition of stationary, walking, driving, or other states; switch to the correct indoor positioning algorithm; and improve the accuracy of localization compared to using a single positioning algorithm. Our experiments show that the recognition of static, walking, driving, and other states improves by 5.5%, 45.47%, 26.23%, and 21% on average, respectively, compared with convolutional neural network (CNN) method. The time delay decreases by approximately 0.5-8.5 s for the transition between states and by approximately 24 s for the entire process.

Deep Learning Scene Recognition Method Based on Localization Enhancement.

With the rapid development of indoor localization in recent years; signals of opportunity have become a reliable and convenient source for indoor localization. The mobile device cannot only capture images of the indoor environment in real-time, but can also obtain one or more different types of signals of opportunity as well. Based on this, we design a convolutional neural network (CNN) model that concatenates features of image data and signals of opportunity for localization by using indoor scene datasets and simulating the situation of indoor location probability. Using the method of transfer learning on the Inception V3 network model feature information is added to assist in scene recognition. The experimental result shows that, for two different experiment sceneries, the accuracies of the prediction results are 97.0% and 96.6% using the proposed model, compared to 69.0% and 81.2% by the method of overlapping positioning information and the base map, and compared to 73.3% and 77.7% by using the fine-tuned Inception V3 model. The accuracy of indoor scene recognition is improved; in particular, the error rate at the spatial connection of different scenes is decreased, and the recognition rate of similar scenes is increased.

[Testing methods for seed quality of Bletilla striata].

In order to provide a basis for establishing seed testing rules and seed quality standard of Bletilla striata, the seed quality of B.striata from different producing area was measured referring to the Rules for Agricultural Seed Testing(GB/T 3543-1995).The results showed that the seeds of B.striata passed through 20-mesh sieve for purity analysis.The weight of seeds was measured by 1000-seed method and the water content was measured at the higher temperature (133±2) ℃ for 3 hours.The seeds were cultured on the wet filter paper at 30 ℃ for 4-20 days in light for germination testing.The method of testing seed viability was that seeds were dipped into 1% TTC solution for 7 hours at temperature of 40 ℃.

[Qualitative characteristics and classification study on commodity specification and grade standard of Panax notoginseng].

Through the markets investigations and literature surveying, this paper investigates and analyzes the qualitative characteristics and commodity condition of Panax notoginseng. And the samples collected from market and origin were analyzed in order to revise the commodity specification and grade standard of P. notoginseng combined with production practice. In this paper, the authors divide the P. notoginseng into 4 commodity specification which are root (including Cunqi and Dongqi ), Rhizome and rootlet according to different parts and harvest time. And the root were divided into 8 grade which are 20, 30, 40, 60, 80, 120, countless and substandard. The density and internal components between the different commodity specification and grade of P. notoginseng were also compared. As well as the effect of different producing area, cultivation years and harvesting time on the commodity specification and grade of P. notoginseng were researched. On this basis, we revise and improve the commodity specification and grade standard of P. notoginseng. Moreover, we suggest the quality control indexes of P. notoginseng should be developed according to the different medicinal part and commodity specification in CHP. In order to guide the standardized production of traditional Chinese medicine and ensure the quality of medicinal materials, the cultivation years and density of each medicinal materials should also be indicated in CHP.

The role of phospholipase D1 in liver fibrosis induced by dimethylnitrosamine in vivo.

BACKGROUND: Phospholipase D (PLD) has been proved to be involved in regulating function of fibroblasts and might play a role in mediating organic fibrosis. AIMS: To investigate the role and mechanism of PLD on dimethylnitrosamine (DMN)-induced rat liver fibrosis. METHODS: Fifty-five male Wistar rats were divided into normal control group, DMN model group, N-methylethanolamine (MEA) control group, and MEA-intervention group. We observed the effects of MEA, a PLD inhibitor on the development and progression of rat liver fibrosis by comparing the physical and biochemical indexes, tissue pathology, PLD activity, and typical markers and cytokines related to fibrosis in the four groups. RESULTS: Accompanied by the down-regulation of PLD1 expression, the MEA-intervention group had improved outcomes compared with the DMN model group in terms of spleen weight, spleen/weight index, serum and tissue biochemical indexes, tissue hydroxyproline, and tissue pathology. The MEA-intervention group had lower TIMP1, COL1A1, and higher MMPs expression level than the DMN model group. The activity of PLD and PLD1, α-SMA expression level in the MEA-intervention group was much lower than those in the DMN model group. There was no significant difference between the two groups in the expression level of TGF-ß1 and MCP1. Meanwhile, there were no significant differences between normal control group and MEA control group in the parameters stated above. CONCLUSION: Phospholipase D1 may play an important role in the development and progression of rat liver fibrosis. Inhibition of PLD may become a new strategy to prevent or alleviate liver fibrosis.

[Study on dynamic change law of N, P and K in Panax notoginseng plant soils with different interval year].

OBJECTIVE: To study effects of different interval year on Panax notoginseng plant soils macro element content. METHOD: The dynamic change of total N, P, K and available N, P, K in soil from Mabai, Matang, Gumu and Panlong was determined under different planting patterns (new soil, interval 5 years soil and continuous cropping soil). RESULT: Contents order of soil total N, P and available N, P were interval 5 years soil > continuous cropping soil > new soil. No significant quarter change on soil total N was found, but the other three showed inverted "v" curve, and the peak value appeared on April 2010. Content of soil total K did not change significantly, but the available K content order was new soil > continuous cropping soil > interval 5 years soil, the quarter change was similar as soil available N or P. The soil total N, P, K and available N, P, K were different of the 4 monitoring sites under the 3 interval planting modes. There was a significant correlation between soil total P and available P under all these 3 interval planting modes, but N and K. The propitiation of N-P-K of new soil, interval 5 years soil and continuous cropping soil were 1: 0.4: 2.4, 1: 0.4:1.4, 1:0. 4:2.0, respectively. CONCLUSION: Continuous cropping pattern induce the accumulation of P, but deficient of K. The imbalance proportion of N, P and K was one of the incentives of continuous cropping induced obstacles. Strengthen the research of optimum proportion of soil N, P and K, and then eliminate continuous cropping obstacles by means of formulated fertilization is the future research direction.

[Study on dynamic change of middle and micro element in Panax notoginseng plant soils with different interval year].

OBJECTIVE: To study effects of different interval year on Panax notoginseng plant soils middle and micro element content. METHOD: The dynamic change of Ca, Mg, Mn, Cu, Zn, B from Mabai, Matang, Gumu and Panlong were determined under different planting patterns (new soil, interval 5 years soil and continuous cropping soil). RESULT: All the micro elements (except Ca, Mg) of interval 5 years soil and continuous cropping soil were significantly higher than those of new soil. All the middle and micro elements (except B) of interval 5 years soil were significantly higher than those of the continuous cropping soil. Planting patterns had remarkable influence on the content of Mn, Cu, B, but not Zn Ca, Mg. Cu, Ca under the 3 planting patterns, and Zn under the continuous cropping pattern did not show significant quarter changes. B content increased with the elongation of implantation time. Zn in new soil and interval 5 years also increased with prolonging of planted time. Mg, Mn and Cu content reached to peak value on April next year, and reached to minimum on the end of this experiment. Compared with new soil, the proportion of Mn, Cu in total elements increased by 29%, 114%, Mg, B decreased by 18%, 38%, Zn and Ca changed slightly of interval 5 years soils; In continuous cropping soil, Mn, Cu and B increased by 50%, 120%, 22%, respectively, but Zn, Ca, Mg had no significant change. CONCLUSION: Continuous cropping pattern could not induce the deficient of soil middle and micro elements, and thereafter might not result in continuous cropping obstacles. But the imbalance proportional of soil middle and micro elements in P. notoginseng plant soils may be one of the main reasons for continuous cropping obstacles.