Drought-flood abrupt alteration events over China.

Drought-flood abrupt alternation (DFAA) is characterized by a period of persistent drought followed by sudden heavy precipitation at a certain level, with impacts on ecosystems and socioeconomic environment. At present, previous studies have mainly focuses on the monthly scale and regional scale. However, this study proposed a multi-indicator daily-scale method for identifying the DFAA occurrence, and explored the DFAA events over China from 1961 to 2018. The DFAA events mainly occurred in the center and southeast of China, especially in the Yangtze River Basin, Pearl River Basin, Huai River Basin, Southeast Rivers Basin, and south part of the Southwest Rivers Basin. The spatial coverage has a statistically significant (p < 0.05) increasing trend over China, of 0.355 %/decade. The occurrence and spatial coverage of DFAA events increased by decades, and were mainly concentrated in summer (around 85 %). The possible formation mechanisms were closely related to global warming, atmospheric circulation index anomalies, soil properties (e.g., soil field capacity), etc.

Continued decline of global soil moisture content, with obvious soil stratification and regional difference.

Soil is an important component connecting atmosphere and vegetation, and is an important 'regulator' of slope hydrological process. Global warming accelerates the global water cycle, and Soil Moisture Content (SMC) will change, but this change is not yet clear. Here, we study the global trend of SMC at different depths over the past 70 years and the next 70 years, based on the GLDAS-NOAH025 dataset and precipitation and temperature data from 15 CMIP6 models. We found that compared with the long-term average of 70 years, the global 0-200 cm SMC is decreasing at a rate of 1.284 kg/m2 per year from 2000 to 2020, and the area showing a significant decreasing trend accounts for 31.67 % of the global. Over the past decade, 0-200 cm SMC reduction rate (2.251 kg/m2) doubled. Global warming and precipitation reduction are the main reasons for the attenuation of SMC at different depths in the global from 2000 to 2020. Under the SSP126, SSP245, SSP370 and SSP585 scenarios, the global 0-200 cm SMC will continue to decay in the future, and the area showing a significant reduction trend accounts for 22.73-49.71 % of the global, but the stratified soil and regional differences are obvious. The attenuation of SMC will further aggravate the global water cycle and enhance the variability of extreme meteorological disasters. We will face more severe soil drought problems.

Lubricant-entrenched slippery surface-based nanocarriers to avoid macrophage uptake and improve drug utilization.

INTRODUCTION: Reducing the protein adsorption of nanoparticles (NPs) as drug carriers to slow their rapid clearance by macrophages uptake is a critical challenge for NPs clinical translational applications. Despite extensive research efforts to inhibit cellular uptake, including covering biological agents or surface chemical coatings to impart "stealth" properties to NPs, their stability remains insufficient. OBJECTIVES: Developed a novel surface modification technology based on a physical infusion engineering approach to achieve persistent inhibition of protein adhesion and cellular uptake by nanocarriers. METHODS: The nanoparticles were prepared based on conventional drug carrier mesoporous silica NPs through a two-step process. A functional nanoscale slippery surface was formed by grafting "liquid-like" brushes on the particles surface, and then a lubricant-entrenched slippery surfaces (LESS) was formed by infusing silicone oil lubricant into the entire surface. Co-incubation with macrophages (in vitro and in vivo) was used to examine the anti-uptake properties of modified NPs. The anti-adhesion properties of LESS coating surfaces to various liquids, proteins and cells were used to analyze the anti-uptake mechanism. Loaded with drugs, combined with tumor models, to evaluate the drug utilization of modified NPs. RESULTS: Relying on the stable and slippery LESS coating, the modified surface could prevent the adhesion of various liquids and effectively shield against the adhesion of proteins and cells, as well as remarkably reduce macrophage cellular uptake in vitro and in vivo. In addition, the LESS coating does not affect cell activity and allows NPs to be loaded with drugs, significantly improving the utilization of drugs in vitro and in vivo. This allows the NPs to reach to the target tumor site for drug delivery without active clearance by macrophages. CONCLUSION: Our research introduces a new nanocarrier technology to improve anti-biofouling performance and stealth efficiency that will facilitate the development of nanomedicines for clinical transformation applications.

A data set of global river networks and corresponding water resources zones divisions v2.

The scale and topological relationship of river networks (RN) and water resources zones (WRZ) directly affect the simulation results of global multi-scale hydrological cycle and the accuracy of water resource refined evaluation. However, few existing global hydrological data sets take account of both aspects simultaneously. Here, we constructed a new hydrologic data set with a spatial resolution of 90 m as an upgraded version of the GRNWRZ V1.0. This data set had proper grading and partitioning thresholds and clear coding of topological relationships. Based on maintaining the accuracy of river networks in the GRNWRZ V1.0, we determined the more refined thresholds and created a new coding rule, which made the grading RN and partitioning WRZ more precise and the topological relationship more intuitive. Supported by this data set, the accuracy and efficiency of the large-scale hydrological simulation can be guaranteed. This data set provides fundamental data support for global water resources governance and global hydrological modeling under climate change.

Determination of human COVID-19 total antibodies in serum using a time-resolved fluorescence immunoassay.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading rapidly around the world. Antibody detection plays an important role in the diagnosis of COVID-19. Here, we established a new time-resolved fluorescence immunoassay (TRFIA) to determine COVID-19 total antibodies. A double-antigen sandwich TRFIA was optimized and established: recombinant nucleocapsid phosphoprotein (N protein) and spike protein (S protein) of COVID-19 immobilized on 96-well plates captured human COVID-19 antibodies and then banded together with the N/S proteins labeled with europium(III) (Eu3+ ) chelates, and finally, time-resolved fluorometry was used to measure the fluorescence values. We successfully established a TRFIA method for the detection of human COVID-19 total antibodies, and the cutoff value was 2.02. There was no cross-reactivity with the negative reference of the National Reference Panel for IgM and IgG antibodies to COVID-19. The CV of the precision assay was 3.19%, and the assay could be stored stably for 15 days at 37°C. Compared with that of the colloidal gold method and chemiluminescence method, the sensitivity of the TRFIA method was higher, and the false positive/negative rate was lower. This established TRFIA has high sensitivity, accuracy, and specificity, which indicates that this method provides a new detection method for the high-throughput routine diagnosis of COVID-19.

Agapetesheana, a new species of A.ser.Longifiles (Ericaceae) from Yunnan, China.

Agapetesheana Y. H. Tong & J. D. Ya (Ericaceae), a new species from Lüchun Xian, Yunnan Province, China is described and illustrated. This new species is assigned to Agapetessect.Agapetesser.Longifiles Airy Shaw. It is closest to A.inopinata Airy Shaw and A.oblonga Craib, but differs in having bead-like tubers, leaf blade with a wholly serrulate margin, subulate and much longer calyx lobes, much larger corollas that are carmine, green at the apex and maroon on angles, and longer stamens without spurs on the back.

Spatiotemporal variation of nitrogen and phosphorus and its main influencing factors in Huangshui River basin.

The foundation of managing excess nutrients in river is the identification of key physical processes and the control of decisive influencing factors. The existing studies seldom consider the influence of rainfall-runoff relationship and only focus on a few anthropogenic activities and natural attributes factors. To address this issue, a comprehensive set of influencing factors including rainfall-runoff relationship (represented by runoff coefficient), basic physical and chemical parameters of water quality, land use types, landscape patterns, topography, and socioeconomic development was constructed in this study. M-K test and cluster analysis were conducted to identify the temporal mutation and spatial clustering characteristics of NH3-N and TP in Huangshui River basin, respectively. Partial least squares regression was used to elucidate the linkages between water contaminants and the factors. As shown in the results, the temporal mutations of NH3-N and TP were obvious in the middle reaches, with 4 out of 7 catchments in the middle reaches have a larger number of mutations of NH3-N than other catchments. The cluster analysis results of NH3-N and TP among catchments were similar. This study also indicated that although the Huangshui River basin was located in the upper reaches of the Yellow River, the influences of rainfall-runoff relationship on spatiotemporal changes of NH3-N and TP in its sub-basins were limited. Only the temporal change of NH3-N in Jintan catchment in the upstream area was significantly affected by runoff coefficient. The indexes of proportion of water area (PWA), proportion of impervious area (PIA), and proportion of primary industry (PPI) were the top three influencing factors of temporal variation of NH3-N and TP for most catchments in the middle reaches. The temporal change of NH3-N in Jintan catchment in the upstream area was obviously affected by runoff coefficient. The spatial variation of NH3-N and TP were all affected by PWA and proportion of secondary industry significantly. The results of this study can provide theoretical basis and technical support for the control and management of nitrogen and phosphorus pollution in upper reaches of rivers.

Intracellular recording of cardiomyocyte action potentials by nanobranched microelectrode array.

Electrophysiological study that records the action potential of cardiomyocyte served as excellent tool to explore cardiology and neuroscience, disease investigation and pharmacological screening. Advances of micro/nanotechnologies promote the development of three-dimensional (3D) nanodevices to record high-quality intracellular recordings by various perforation approaches of cells, however, the complicated fabrication processes limited their large-scale manufacture. In this work, a unique nanobranched microelectrode array (NBMEA) platform is developed to achieve high-quality intracellular recording of cultured cardiomyocytes in a minimally invasive manner. The NBMEA is consisting of high aspect ratio conductive nanobranches fabricated on patterned microelectrodes combining hydrothermal growth and standard microfabrication. The 3D structure of nanobranches enables the electrode to form tight coupling with cardiomyocytes to achieve the low voltage cell electroporation and high-quality intracellular recording. The recorded intracellular action potentials of cardiomyocytes by NBMEA exhibited significant enhancement on amplitude (~5 mV), signal-to-noise ratio (SNR) (~67.47 dB), recording duration (up to 105 min), and recording yield (69.5 ± 17.8%). This NBMEA platform is a promising and powerful tool for electrophysiology that opens up new opportunities for high-quality and stable intracellular recording of cardiomyocytes.

Antibody-free isolation and regulation of adherent cancer cells via hybrid branched microtube-sandwiched hydrodynamic system.

The detection of circulating tumor cells (CTCs) has achieved promising progress for early diagnosis and disease analysis. Microfluidic chip techniques have recently promoted the technologies of CTC sorting and analysis, yet seldom can the microfluidic chips for CTC enrichment via antibody-free capture provide in situ regulation of both extracellular and intracellular activity, which would be advantageous for cell-based pharmaceutical therapeutics and screening. Herein, we have demonstrated a hybrid TiO2/ZnO branched microtube array (HBMTA)-sandwiched hydrodynamic device that integrates the multiple functions of selective enrichment of adherent tumor cells in an antibody-free manner and in situ delivery to the extracellular and intracellular spaces of the enriched tumor cells. More than 90% cancer cells were enriched on the device due to their preferential adhesion with the nano-branches of HBMTA, while more than 91% blood cells were eliminated from the device by constant hydrodynamic fluid shearing. For in situ regulation, temporally and spatially controlled extracellular delivery to the enriched tumor cells could be precisely achieved through the hollow structures of the HBMTA. In addition, reagents (e.g. propidium iodide) could be delivered into the intracellular spaces of enriched tumor cells by coupling an electric field to nondestructively perforate the cell membrane. Our study not only offers a promising and facile strategy for antibody-free isolation of tumor cells, but also provides unique opportunities to facilitate cancer research, including antitumor drug screening and personalized therapeutics.

Intracellular Delivery and Sensing System Based on Electroplated Conductive Nanostraw Arrays.

One-dimensional nanoneedle-like arrays have emerged as an attractive tool for penetrating the cell membrane to achieve intracellular applications including drug delivery, electrical recording, and biochemical detection. Hollow nanoneedles, also called nanostraws (NSs), combined with nanoelectroporation have been demonstrated as a powerful platform for intracellular drug delivery and extraction of intracellular contents. However, the fabrication technique of nanostraws still requires complicated and expensive atomic layer deposition and etching processes and fails to produce conductive nanostraws. Herein, we developed a commonly accessible and versatile electrodeposition approach to controllably fabricate conductive nanostraw arrays based on various types of metal or conductive polymer materials. Representatively, Pt nanostraws (Pt NSs) with 400 nm diameter were further integrated with a low-voltage nanoelectroporation system to achieve cell detection, intracellular drug delivery, and sensing of intracellular enzymes. Both theoretical simulations and experimental results revealed that the conductive nanostraws in direct contact with cells could induce high-efficiency cell electroporation at relatively low voltage (∼5 V). Efficient delivery of reagents into live cells with spatial control and repeated extraction of intracellular enzymes (e.g., caspase-3) for temporal monitoring from the same set of cells were demonstrated. This work not only pioneers a new avenue for universal production of conductive nanostraws on a large scale but also presents great potential for developing nanodevices to achieve a variety of biomedical applications including cell re-engineering, cell-based therapy, and signaling pathway monitoring.

Multifunctional Branched Nanostraw-Electroporation Platform for Intracellular Regulation and Monitoring of Circulating Tumor Cells.

Downstream analysis of circulating tumor cells (CTCs) has provided new insights into cancer research. In particular, the detection of CTCs, followed by the regulation and monitoring of their intracellular activities, can provide valuable information for comprehensively understanding cancer pathogenesis and progression. However, current CTC detection techniques are rarely capable of in situ regulation and monitoring of the intracellular microenvironments of cancer cells over time. Here, we developed a multifunctional branched nanostraw (BNS)-electroporation platform that could effectively capture CTCs and allow for downstream regulation and monitoring of their intracellular activities in a real-time and in situ manner. The BNSs possessed numerous nanobranches on the outer sidewall of hollow nanotubes, which could be conjugated with specific antibodies to facilitate the effective capture of CTCs. Nanoelectroporation could be applied through the BNSs to nondestructively porate the membranes of the captured cells at a low voltage, allowing the delivery of exogenous biomolecules into the cytosol and the extraction of cytosolic contents through the BNSs without affecting cell viability. The efficient delivery of biomolecules (e.g., small molecule dyes and DNA plasmids) into cancer cells with spatial and temporal control and, conversely, the repeated extraction of intracellular enzymes (e.g., caspase-3) for real-time monitoring were both demonstrated. This technology can provide new opportunities for the comprehensive understanding of cancer cell functions that will facilitate cancer diagnosis and treatment.

A multicenter, prospective evaluation of the Chinese Society of Thrombosis and Hemostasis Scoring System for disseminated intravascular coagulation.

INTRODUCTION: Disseminated intravascular coagulation (DIC) is a severe complication of critical conditions. There are several scoring systems used for the diagnosis of DIC, including the International Society on Thrombosis and Hemostasis (ISTH) Overt-DIC criteria, the Japanese Ministry of Health and Welfare (JMHW) criteria and the Chinese Society of Thrombosis and Hemostasis scoring system for DIC (CDSS). The objective of this prospective study was to evaluate the accuracy and predictive value of the CDSS. MATERIALS AND METHODS: 1318 patients, aged 18-70 years old and suspected of DIC were enrolled from 18 hospitals across China. Participants were divided into two groups for analysis (group 1, non-hematological diseases; group 2, hematological diseases). 242 patients were excluded because of incomplete data collection and failure to follow-up. RESULTS AND CONCLUSIONS: The rates of concordance of diagnosis of DIC between the CDSS and two other scoring systems were close to 80%. The area under ROC curves of CDSS had a slight advantage when using the ISTH, JMHW criteria or prognosis as gold standard, respectively. The CDSS DIC was an independent predictor of mortality, and its odds-ratio was superior or comparable to that of the ISTH and JMHW criteria in the two groups. The CDSS DIC score also had a significant correlation with the APACHE II and SOFA score (p < 0.05). In summary, as a quantification standard of the Chinese experts' consensus, the CDSS is conducive to the standardized diagnosis of DIC because of its favorable diagnostic and prognostic utility.

PI3K/Akt signaling transduction pathway, erythropoiesis and glycolysis in hypoxia (Review).

The purpose of this review is to summarize the research progress of PI3K/Akt signaling pathway in erythropoiesis and glycolysis. Phosphatidylinositol­4,5­bisphosphate 3­kinase (PI3K) is activated by numerous genes and leads to protein kinase B (Akt) binding to the cell membrane, with the help of phosphoinositide­dependent kinase, in the PI3K/Akt signal transduction pathway. Threonine and serine phosphorylation contribute to Akt translocation from the cytoplasm to the nucleus and further mediates enzymatic biological effects, including those involved in cell proliferation, apoptosis inhibition, cell migration, vesicle transport and cell cancerous transformation. As a key downstream protein of the PI3K/Akt signaling pathway, hypoxia­inducible factor (HIF)­1 is closely associated with the concentration of oxygen in the environment. Maintaining stable levels of HIF­1 protein is critical under normoxic conditions; however, HIF­1 levels quickly increase under hypoxic conditions. HIF­1α is involved in the acute hypoxic response associated with erythropoietin, whereas HIF­2α is associated with the response to chronic hypoxia. Furthermore, PI3K/Akt can reduce the synthesis of glycogen and increase glycolysis. Inhibition of glycogen synthase kinase 3ß activity by phosphorylation of its N­terminal serine increases accumulation of cyclin D1, which promotes the cell cycle and improves cell proliferation through the PI3K/Akt signaling pathway. The PI3K/Akt signaling pathway is closely associated with a variety of enzymatic biological effects and glucose metabolism.

Chinese guidelines for treatment of adult primary immune thrombocytopenia.

Primary immune thrombocytopenia (ITP) is a bleeding disorder commonly encountered in clinical practice. The International Working Group (IWG) on ITP has published several landmark papers on terminology, definitions, outcome criteria, bleeding assessment, diagnosis, and management of ITP. The Chinese consensus reports for diagnosis and management of adult ITP have been updated to the 4th edition. Based on current consensus positions and new emerging clinical evidence, the thrombosis and hemostasis group of the Chinese Society of Hematology issued Chinese guidelines for management of adult ITP, which aim to provide evidence-based recommendations for clinical decision making.

[Determination of six active ingredients in different parts of Belamcanda chinensis and Iris tectorum and their anti-inflammatory activity].

In order to explore the anti-inflammatory activity and active ingredient basis from the leaves of the Belamcanda chinensis and Iris tectorum, we established an HPLC method for simultaneous determination of six anti-inflammatory active ingredient contents in the root of the B. chinensis and I. tectorum as well as their leaves with different dry methods, and the anti-inflammatory effects of the extract were studied by the mouse ear swelling experiment. The HPLC analysis was performed on an Agilent WondaSil© C18-WR(4.6 mm×250 mm，5 µm)，with isocratic elution of acetonitrile-0.1% ortho-phosphoric acid solution at a flow rate of 1. 0 mL·min⁻¹ and the detection was carried out at 265 nm. The chemical compositions of the B. chinensis and I. tectorum are similar but the contents of them are obviously different. Both rhizome and leaf extract of B. chinensis and I. tectorum had inhibitory effects on inflamed mice induced by dimethylbenzene and had anti-inflammatory effects by animal experiment, which could lay the material and active foundation for the development of the non-medicinal parts of the B. chinensis and I. tectorum.

Evaluation of the new Chinese Disseminated Intravascular Coagulation Scoring System in critically ill patients: A multicenter prospective study.

Disseminated intravascular coagulation (DIC) is a common life-threatening complication in critically ill patients. The diagnostic scoring systems of DIC enable a more prompt and accurate diagnosis of DIC, such as the International Society on Thrombosis and Haemostasis (ISTH), the Japanese Association for Acute Medicine (JAAM) and the Japanese Ministry of Health and Welfare (JMHW). This study prospectively evaluated the newly proposed Chinese DIC Scoring System (CDSS), which was conducted at 18 centers in China during a one-year period. Receiver operating characteristic (ROC) curves showed that, for diagnosis of DIC and for prediction of the 28-day all-cause mortality, the CDSS had larger areas under the ROC curve (AUCs) than the ISTH and the JAAM in different groups. The CDSS also had larger AUC than the JMHW for the ISTH DIC in non-infectious diseases. All of the AUCs of the CDSS were greater than 0.8, accompanied with both high sensitivity and high specificity. Furthermore, the CDSS score was an independent predictor of mortality (odds ratio, 1.882; p < 0.001), and could reflect the illness severity (p < 0.001 for Spearman's rank correlations with the scores of severity). In conclusion, the CDSS is worthy of promotion with a better diagnostic and prognostic value for DIC.

[Changes of Neutrophil CD64 in Patients with Hematological Mali-gnancies Combined with Bacterial Infections].

OBJECTIVE: To explore the changes of CD64 on surface of neutrophils in patients with hematological malignancies combined with bacterial infections. METHODS: Ninety-seven patients with hematological tumor admitted in our hospital from August 2014 to February 2016 were selected and divided into 2 groups: infection group(50 cases) and noninfection group(47 cases) according to their symptoms, physical sings and blood culture results for microbiologic detection. The CD46 index on surface of neutrophils, serum C- reactive protein (CRP), neutrophil count (NC) and procalcitonin (PCT) level were detected by flow cytometry. After treatment of infection patients, the CD46 index, CRP, PCT and NC were detected again. RESULTS: Before antibacterial treatment of patients, the CD64 index in infection group was significantly higher than that in noninfection group, the CRP, PCT and NC levels in infection group also were higher than those in noninfection group; after antibacterial treatment, the CD64 index, CRP, PCT and NC levels in infection group decresed. CONCLUSION: The CD64 index in hematologic malignancy patients complicated with bacterial infections significantly increased, after antibacterial treatment these indexes decreases, confirming the value of CD64 in the diagnosis of bacterial infections for patients with hematologic malignancies.

Decreased miR-144 expression as a non-invasive biomarker for acute myeloid leukemia patients.

MicroRNAs are found to be stable in blood and they demonstrated tissue specific expression patterns. Thus, they may be used as potential non-invasive biomarkers of specific cancers. In the current study, we mainly focused on miR-144, which has never been studied in acute myeloid leukemia (AML). The expression of miR-144 was explored in the bone marrow and peripheral blood of AML patients and healthy control. The correlation between peripheral blood miR-144 level and key clinical parameters, including overall survival and prognostic value, was further explored. We showed that miR-144 was markedly reduced in both the peripheral blood and bone marrow of AML patients compared with healthy controls. Further study revealed that there is a significant correlation between peripheral blood miR-144 level and FAB classification (p=0.0023) and cytogenetics (p=0.001). More importantly, a lower expression of peripheral blood miR-144 level was found to be positively correlated with poorer overall survival rate. In summary, peripheral blood miR-144 may be utilized as a potential novel non-invasive biomarker for AML screening.

[Significance of Plasma HMGB1, IFN-γ, IL-4 and TLR4 Expression on CD4+T Cell Surface in Patients with Immune Thrombocytopenia].

OBJECTIVE: To investigate the effects of plasma HMGB1, IFN-γ, IL-4 and CD4+T cell surface TLR4 expression on the immune thrombocytopenia(ITP). METHODS: Twenty-five patients diagnosed as ITP in our hospital from October 2014 to October 2015, and 20 healthy persons as controls were selected. The ELISA was used to detect the plasma levels of HMGB1, IFN-γ and IL-4 in 2 groups; the flow cytometry was used to detect the expression level of TLR4 on the surface of CD4+ cells. The relatienship between different parameters was analyzed. RESULTS: Before treatment, the plasma HMGB1 level in ITP group was significantly higher than that in control group (t=4.259, P<0.01), while after treatment it significantly decreased and close to level in control group (t=1.267, P>0.05). The plasma IFN-γ level detected in ITP group before and after treatment was not significantly different from level in control group (P>0.05), while the IL-4 level in ITP group before treatment was significantly lower than that in control grup (t=2.107, P<0.05), but the IL-4 level in ITP group after treatment was significantly higher than that in control group (t=2.107, P<0.05). The plasma IFN-γ/IL-4 ratio in ITP group before treatment was significantly higher than that in control group (t=5.436, P<0.01), but it obviously decreased and was slightly lower than that in control group after treatment. The expression level of TLR4 in ITP group before and after treatment was all significantly lower than that in control group (P<0.01). The HMGB1 level in ITP group was directly proportional to the CD3+ content (r=0.824, P<0.01), however it not significantly related with CD4+ content (r=0.074, P>0.05), but than the HMGB1 level in ITP group was directly proportional to CD8+ content (r=0.844, P<0.01) and to IL-4 content (r=0.784, P<0.01), and was inversely proportional to IFN-γ level(r=-0.814,P<0.01),and also was inversely proportional to IFN-γ /IL-4 ratio(r=-0.887,P<0.01),and directly proportional to TLR4 expression level(r=0.772,P<0.01). CONCLUSION: The HMGB1 and TLR4 expression levels in ITP patients are higher, and clinical therapy can relieve the disease by targetly control in HMGB1 and TLR4 expression.