Clinical Epidemiology in China series. Paper 1: Evidence-based medicine in China: An oral history study

OBJECTIVE

To describe and record the evolution of EBM in China.

STUDY DESIGN AND SETTING

We conducted the study following the general methodology of oral history. The interviews were done at Lanzhou University, between 18^th and 22^nd April 2019 using pre-defined questions. All interviews were videorecorded. Two investigators extracted and analyzed the information from the interviews independently.

RESULTS

One international expert and ten Chinese experts participated in the interviews. After the introduction of EBM in China in the mid-1990s, more than 20 EBM centres have been established. According to the interviewees, Gordon Guyatt, David Sackett and Iain Chalmers are the international experts who played the most important role in the development of EBM in China. China has contributed to EBM on the international level by conducting systematic reviews, developing reporting checklists, and introducing the principles of EBM into Traditional Medicine. The Chinese Cochrane Centre and the EBM Centre of Lanzhou University were ranked the top two EBM Centres in China by the interviewees.

CONCLUSION

EBM has been developing in China for nearly a quarter of a century. Many achievements have been reached, however, EBM is still facing many challenges in China, including shortages of funding support and personnel, as well as limited local high-quality evidence.

A combination of cecum microbiome and metabolome in CUMS depressed rats reveals the antidepressant mechanism of traditional Chinese medicines: A case study of Xiaoyaosan

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaoyaosan (XYS), a representative and classic prescription in traditional Chinese medicines (TCMs), has been used for thousands of years for treating depression. The anti-depression effect of XYS has been demonstrated both clinically and experimentally. However, it is still unclear that whether XYS could regulate the abnormalities of gut microbiota and metabolites of cecum induced by depression, and in which way. This study aimed to explore the underlying mechanism of the anti-depressant effects of XYS from the perspective of cecal microbiota and metabolites.

MATERIALS AND METHODS

Chronic unpredictable mild stress (CUMS)-induced depression-like rats were used as the depression animal model. Various classic behavioral tests were performed to assess the anti-depressant effects of XYS. Additionally, the composition, the richness, and the diversity of the cecum microbiota were assessed by 16S rRNA gene sequencing technology. Besides, the metabolic profiling of cecum samples was analyzed by 1H-NMR metabolomics. Multivariate data analysis was then applied to screen the differential metabolites and to characterize the changes in cecum metabolites. Moreover, a correlation analysis between differential metabolites and crucial microbiota was conducted.

RESULTS

XYS significantly improved depressive behaviors and the abnormal diversity of cecum microbiota induced by CUMS. At the phylum level, XYS could significantly increase the abundance of Firmicutes while decrease the abundance of Actinobacteria in depressed rats. XYS significantly regulated the abundances of 9 out of 13 potential microbial biomarkers at the genus level. Cecal metabolomics showed that XYS could also regulate the abnormal levels of alanine, proline, lactate, and valine of depression rats.

CONCLUSIONS

This study revealed, for the first time, from the perspectives of microbiota and cecum metabolites, the anti-depression mechanisms of XYS. This study is of significance for not only comprehensively understanding the anti-depression effects and mechanisms of XYS, but also for providing a research approach for revealing the underlying mechanisms of action of TCMs, i.e. to apply a combination of 16S rRNA gene sequencing and metabolomics.

Conventional transarterial chemoembolization combined with systemic therapy versus systemic therapy alone as second-line treatment for unresectable colorectal liver metastases: randomized clinical trial

BACKGROUND

The combination of conventional transarterial chemoembolization (cTACE) and systemic therapy has the potential to treat chemotherapy-refractory unresectable colorectal liver metastases (CRLMs). This study aimed to compare survival after this combined treatment versus systemic chemotherapy alone.

METHODS

This single-centre RCT included patients with unresectable CRLMs that progressed after first-line treatment. Patients were randomized on a 1 : 1 basis to either systemic chemotherapy with or without cTACE, without further stratification. The primary outcome was progression-free survival (PFS). Secondary outcomes were overall response rate, disease control rate, conversion rate to liver resection, overall survival, and adverse events.

RESULTS

Of 180 patients recruited, 168 were randomized. Eighty-five patients in arm A received systemic chemotherapy plus cTACE and 83 in arm B received systemic chemotherapy alone. Median PFS was longer in arm A than B (6.7 versus 3.8 months; hazard ratio (HR) 0.67, 95 per cent c.i. 0.49 to 0.91; P = 0.009), but did not translate into prolonged median overall survival (18.4 versus 14.8 months; HR = 0.92, 0.62 to 1.36; P = 0.669). Overall response rates (20 versus 22 per cent; P = 0.788) and conversion rate to liver resection (18 versus 16 per cent; P = 0.730) were no different between arms A and B. The disease control rate was higher in arm A than arm B (67 versus 51 per cent; P = 0.030). No adverse event higher than grade 3 according to the Common Terminology Criteria for Adverse Events was observed during treatment.

CONCLUSION

Systemic chemotherapy plus cTACE is a safe option as second-line treatment for unresectable colorectal liver metastases, with a modest effect on PFS. Registration number: NCT03783559 (http://www.clinicaltrials.gov).

Spatial-Spectral Density Peaks-Based Discriminant Analysis for Membranous Nephropathy Classification Using Microscopic Hyperspectral Images

The traditional differential diagnosis of membranous nephropathy (MN) mainly relies on clinical symptoms, serological examination and optical renal biopsy. However, there is a probability of false positives in the optical inspection results, and it is unable to detect the change of biochemical components, which poses an obstacle to pathogenic mechanism analysis. Microscopic hyperspectral imaging can reveal detailed component information of immune complexes, but the high dimensionality of microscopic hyperspectral image brings difficulties and challenges to image processing and disease diagnosis. In this paper, a novel classification framework, including spatial-spectral density peaks-based discriminant analysis (SSDP), is proposed for intelligent diagnosis of MN using a microscopic hyperspectral pathological dataset. SSDP constructs a set of graphs describing intrinsic structure of MHSI in both spatial and spectral domains by employing density peak clustering. In the process of graph embedding, low-dimensional features with important diagnostic information in the immune complex are obtained by compacting the spatial-spectral local intra-class pixels while separating the spectral inter-class pixels. For the MN recognition task, a support vector machine (SVM) is used to classify pixels in the low-dimensional space. Experimental validation data employ two types of MN that are difficult to distinguish with optical microscope, including primary MN and hepatitis B virus-associated MN. Experimental results show that the proposed SSDP achieves a sensitivity of 99.36%, which has potential clinical value for automatic diagnosis of MN.

Developing evidenced-based quality assessment checklist for real practice in primary health care using standardized patients: a systematic review

BACKGROUND

The aim of this review was to explore the quality assessment checklists development methods in previous researches using standardized patients (SPs), as well as to propose an evidence-based checklist development procedure for quality assessment of common conditions in primary health care (PHC) settings.

METHODS

We conducted a systematic review of studies that described checklist development method and extracted the methodology in terms of the developer, the basis and processes. Based on that, we formulated the development procedure according to the recommendations of the WHO Handbook for Guideline Development.

RESULTS

We identified a total of 13 articles, and proposed the following five key steps: (I) forming a multidisciplinary team; (II) selecting and evaluating relevant references; (III) extracting medical information and forming the basic items; (IV) clinical expert consensus on the items; and (V) pre-testing the item pool and determining final items.

DISCUSSION

SP has been proven to be an effective method to assess performance in practice. There are still some deficiencies in the developing of case-specific checklists using SPs. To ensure the validity and reliability of checklists, the development processes need to be more standardized and procedural.

Anti-depressive effects of Xiaoyaosan, Shugan and Jianpi herbal treatments: Role on the gut microbiome of CUMS rats

BACKGROUND

Xiaoyaosan (XYS), a classic traditional Chinese medicine (TCM) prescription that contained eight Chinese herbs, has been used for treating depression for thousands of years. Yet, the underlying mechanisms are still unclear, which need to be investigated from various perspectives. Disassembling a prescription is one of the effective approaches to study the effects and the mechanisms of TCM prescriptions. By disassembling the prescription, we can find effective combinations of individual herbs to simplify the scale of a given prescription. Accordingly, herein, XYS was disassembled into Shugan and Jianpi groups.

PURPOSE

This study aimed to explore the anti-depressive effects of XYS and its disassembled groups on the digestive system functions and the cecal microbiota of rats.

METHODS

XYS was divided into two efficacy groups, i.e., the Shugan (SG) and the Jianpi (JP) groups. A depression model was applied by using the chronic unpredictable mild stress (CUMS) method. Various classic behavioral tests were performed to assess the anti-depressive effects of the XYS, the SG, and the JP. Afterward, the effects of the three groups on the digestive system functions and the cecum microbiota of depression rats were evaluated. On top of this, correlation analyses between behavioral and digestive system function indexes and cecum microbiota were conducted.

RESULTS

The XYS, the SG, and the JP had significant callback effects on depressive behaviors and gastrointestinal dysfunctions of CUMS rats. The compositions of the gut bacterial community were variable among the five groups. The community composition of the SG was the most similar to that of NC, followed by the XYS and the JP. At phylum, family, and genus levels, 31 potential microbial biomarkers associated with CUMS were identified. Twenty biomarkers were significantly reversed by the SG while 16 and 11 biomarkers were reversed by the XYS and the JP, respectively. The results of degrees of regulatory effects showed that the SG had the highest efficacy index (EI) than the XYS and the JP.

CONCLUSION

Regarding the regulation of cecal microbiota of depression rats, the SG treatment was better than XYS and JP. Therefore, SG could be used individually for the clinical treatment of depression, especially in patients with gastrointestinal and gut microbiota disorders.

MiR-200b-5p inhibits proliferation of ovarian cancer cells by targeting ATAD2 and regulating PI3K/AKT signaling pathway

OBJECTIVE

The purpose of this study was to investigate the influences of micro ribonucleic acid (miR)-200b-5p on proliferation and apoptosis of ovarian cancer (OC) cells, and to explore its correlations with the target gene ATPase family, AAA domain containing 2 (ATAD2), and the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway.

MATERIALS AND METHODS

Human ovarian fibroblasts (HOFs) or human OC cell lines (A2780) were cultured in vitro, and then, A2780 cells were separately transfected with miR-200b mimics or miR-NC or cultured with ATAD2-specific inhibitor BAY-850. Thereafter, the expression levels of miR-200b and ATAD2 messenger RNA (mRNA) were measured via qRT-PCR, and the proliferative capacity of cells was detected by CCK-8 assay. Next, the cell apoptosis was determined by means of flow cytometry and one-step TUNEL assay. Finally, the targeted regulatory relationship between miR-200b and ATAD2 was examined using a Luciferase reporter assay system, and the protein expressions were detected through Western blot (WB) assay.

RESULTS

It was found that the expression level of miR-200b was remarkably lower (p<0.05), while the mRNA expression level of ATAD2 was notably higher (p<0.05) in A2780 cells than those in HOFs. The transfection with miR-200b mimics markedly reduced the mRNA expression level of ATAD2 (p<0.05) and the proliferative capacity (p<0.05) and increased the apoptosis rate (p<0.05) of A2780 cells. Besides, it was detected via the Luciferase reporter assay system that miR-200b inhibited ATAD2. BAY-850 significantly decreased the expression level of ATAD2 protein (p<0.05) and the proliferative capacity (p<0.05) but improved the apoptosis rate (p<0.05) of cells. Moreover, both miR-200b mimics and BAY-850 could distinctly repress the protein expression levels of PI3K and p-Akt of the PI3K/Akt signaling pathway (p<0.05) and enhance the expression of suppressor gene p53 (p<0.05).

CONCLUSIONS

MiR-200b-5p can inhibit the proliferation and promote the apoptosis of OC cells through targeted inhibition of ATAD2 expression and regulation of the PI3K/Akt signaling pathway.

Washed Microbiota Transplantation Accelerates the Recovery of Abnormal Changes by Light-Induced Stress in Tree Shrews

The gut and brain interact constantly in a complex fashion. Its intricacy and intrigue is progressively being revealed in the study of the "gut-brain axis". Among many factors, abnormal light exposure is a potential powerful stressor, which is becoming ever more pervasive in our modern society. However, little is known about how stress, induced by staying up late by light, affects the gut-brain axis. We addressed this question by extending the normal circadian light for four hours at night in fifteen male tree shrews to simulate the pattern of staying up late in humans. The behavior, biochemical tests, microbiota dynamics, and brain structure of tree shrews were evaluated. The simple prolongation of light in the environment resulted in substantial changes of body weight loss, behavioral differences, total sleep time reduction, and an increased level of urine cortisol. These alterations were rescued by the treatment of either ketamine or washed microbiota transplantation (WMT). Importantly, the sustainability of WMT effect was better than that of ketamine. Magnetic Resonance Imaging analysis indicated that ketamine acted on the hippocampus and thalamus, and WMT mainly affected the piriform cortex and lateral geniculate nucleus. In conclusion, long-term light stimulation could change the behaviors, composition of gut microbiota and brain structure in tree shrews. Targeting microbiota thus certainly holds promise as a treatment for neuropsychiatric disorders, including but not limited to stress-related diseases.

Bound electron screening effect on ion-ion potential of warm and hot dense matter

The effects of bound electron screening in warm and hot dense matter are investigated analytically and a theoretical description of screened short-range repulsion is given meanwhile. An empirical ion-ion potential including the classic charge screening and chemical bond attraction at various temperatures and densities is proposed. By solving hypernetted chain equations and comparing the obtained radial distribution function (RDF) with ab initio simulations, the proposed ion-ion potential is found to be promising over a wide range of temperatures and densities for warm dense aluminum and iron. The elastic scattering amplitude and the x-ray absorption near the edge structure of warm dense aluminum calculated from the obtained RDF are in good agreement with experiment results.

M2 macrophages, but not M1 macrophages, support megakaryopoiesis by upregulating PI3K-AKT pathway activity

Dysfunctional megakaryopoiesis hampers platelet production, which is closely associated with thrombocytopenia (PT). Macrophages (MФs) are crucial cellular components in the bone marrow (BM) microenvironment. However, the specific effects of M1 MФs or M2 MФs on regulating megakaryocytes (MKs) are largely unknown. In the current study, aberrant BM-M1/M2 MФ polarization, characterized by increased M1 MФs and decreased M2 MФs and accompanied by impaired megakaryopoiesis-supporting abilities, was found in patients with PT post-allotransplant. RNA-seq and western blot analysis showed that the PI3K-AKT pathway was downregulated in the BM MФs of PT patients. Moreover, in vitro treatment with PI3K-AKT activators restored the impaired megakaryopoiesis-supporting ability of MФs from PT patients. Furthermore, we found M1 MФs suppress, whereas M2 MФs support MK maturation and platelet formation in humans. Chemical inhibition of PI3K-AKT pathway reduced megakaryopoiesis-supporting ability of M2 MФs, as indicated by decreased MK count, colony-forming unit number, high-ploidy distribution, and platelet count. Importantly, genetic knockdown of the PI3K-AKT pathway impaired the megakaryopoiesis-supporting ability of MФs both in vitro and in a MФ-specific PI3K-knockdown murine model, indicating a critical role of PI3K-AKT pathway in regulating the megakaryopoiesis-supporting ability of M2 MФs. Furthermore, our preliminary data indicated that TGF-β released by M2 MФs may facilitate megakaryopoiesis through upregulation of the JAK2/STAT5 and MAPK/ERK pathways in MKs. Taken together, our data reveal that M1 and M2 MФs have opposing effects on MKs in a PI3K-AKT pathway-dependent manner, which may lead to new insights into the pathogenesis of thrombocytopenia and provide a potential therapeutic strategy to promote megakaryopoiesis.

Tumor-associated macrophages-mediated CXCL8 infiltration enhances breast cancer metastasis: Suppression by Danirixin

Breast cancer is the most frequent cancer among females and the second most common cause of cancer deaths worldwide. Tumor-associated macrophages (TAMs) are the most abundant immune cell population in the tumor microenvironment, including breast cancer. Breast cancer stem cells (BCSCs) play an important role in regulating breast cancer growth and metastasis, which still remains an obstacle for successful treatment of breast cancer and requires further investigation, as well as the potential therapeutic strategies. Cytokine array validated that C-X-C motif chemokine ligand 8 (CXCL8) is a pivotal chemokine secreted by TAMs, and CXCL8 could enhance breast cancer migration, invasion ability, and epithelial-mesenchymal transition (EMT) in both animal and human breast cancer. In this study, the clinical data firstly indicated that high CXCL8 expression was significantly associated with metastasis and tumor growth in breast cancer patients. Then, we showed that TAMs-released CXCL8 could markedly elevate the migration, invasion and EMT events in breast cancer cells, as well as the self-renewal of BCSCs in vitro. These processes were markedly abrogated by the treatment of Danirixin, a reversible and selective antagonist of CXC chemokine receptor 2 (CXCR2). Consistently, the in vivo analysis confirmed that CXCL8 suppression using Danirixin effectively reduced the tumor growth, lung metastasis and repressed the self-renewal of BCSCs. Collectively, TAMs/CXCL8 could enhance BCSCs self-renewal and breast cancer metastasis, and these effects could be markedly abolished by Danirixin treatment, suppressing breast cancer progression consequently. Therefore, Danirixin could be considered as a novel and effective therapeutic strategy for breast cancer treatment without obvious toxicity to major organs.

Organisational innovation climate and innovation behaviour among nurses in China: A mediation model of psychological empowerment

AIM

This study aimed to explore the effect of organisational innovation climate on nurse innovation behaviour and the mediating role of psychological empowerment.

BACKGROUND

Encouraging nurses to generate more innovative behaviours has become an important development direction for improving the quality of nursing services.

METHOD

We employed a self-report questionnaire to collect data in Jinan City, China. A total of 2018 valid surveys were obtained. Hierarchical multiple regression model analysis was conducted to test the study hypothesis.

RESULT

The mean values of innovation behaviour and organisational innovation climate were 35.29 and 83.30, respectively. Psychological empowerment was found to have partially mediating effect on the relationship between organisational innovation climate and innovation behaviour.

CONCLUSION

Organisational innovation climate has significant impact on innovation behaviour, and it can indirectly affect innovation behaviour via the mediating role of psychological empowerment.

IMPLICATIONS FOR NURSING MANAGEMENT

Nursing managers should enhance innovation climate through formal rules, procedures and training activities. They can establish resource guarantee system and information sharing platform, and strengthen work autonomy for nurses to improve their psychological empowerment.

Hepatic metabolomics of the compatibility effect of Xiaoyaosan on CUMS-induced depression based on the TCM theory of "Treating Diseases via Regulating the Liver's Function"

This study aimed to demonstrate the scientific connotations and compatibility effects of Xiaoyaosan (XYS) based on the theory of "Treating Diseases via Regulating the Liver's Function" by hepatic metabolomics. XYS was divided into two efficacy groups, i.e. the Shugan (SG) and the Jianpi (JP) groups, according to the strategy of "Efficacy Compositions". The chronic unpredictable mild stress (CUMS) depression model was constructed. A ¹H NMR-based hepatic metabolomics approach coupled with multivariate data (MVD) analysis was performed. Meanwhile, relative distance (RD) and Efficacy Index (EI) were calculated. XYS and its efficacy groups significantly reversed the abnormality of behavior and hepatic metabolomics of depression rats, but to different degrees. The results of ethology and metabolomics showed the same order, i.e. XYS > JP > SG. Two metabolites, i.e. tyrosine and malate, were regulated by all the treatment groups. Four metabolites were significantly regulated only by XYS group. Of note, the results showed the two efficacy groups of XYS exhibited synergistic anti-depression effects, and glutamate, malate and taurine could be the key hepatic metabolites for these synergistic effects. The current study not only complements and consummates the mechanisms of depression and the anti-depression effects of XYS from the perspective of hepatic metabolomics, but also lays a solid foundation for comprehensively and deeply understanding the compatibility effects of XYS against depression, especially from the points of view of compatibility in Traditional Chinese medicine (TCM) theory and synergism in modern medicine theory.

Serum metabolomics reveals compatibility rules of the antidepressant effects of Xiaoyaosan and its efficacy groups

Traditional Chinese medicines (TCMs) have attracted more attentions in the treatment of depression. Xiaoyaosan (XYS), a classic anti-depression TCM prescription, contains eight herbs. However, the compatibility effects of XYS in modern pharmacology need to be investigated in depth. In this study, the chronic unpredictable mild stress (CUMS) depression-like model was constructed. Afterwards, XYS was divided into the Shugan and the Jianpi groups according to the research strategy ofefficacy groups. Meanwhile, a proton nuclear magnetic resonance spectrometry (¹H NMR) based serum metabolomics was applied. XYS and its efficacy groups significantly regulated the abnormal levels of differential metabolites related to depression, but to different degrees. Metabolic profiling by orthogonal partial least squares discriminant analysis showed that XYS at high dose (XH) exhibited the strongest effects than other treatment groups. Ten metabolites related to depression were identified as differential metabolites. Besides, relative distance (R_d) was calculated to quantitatively evaluate the effects. We found that XH group had the highest R_d value. Moreover, among the five metabolic pathways of depression, XYS and Jianpi groups significantly regulated all pathways while Shugan group regulated four pathways. These findings lay a solid foundation for comprehensively and deeply understanding the compatibility effects of XYS against depression.

Membranous nephropathy classification using microscopic hyperspectral imaging and tensor patch-based discriminative linear regression

Optical kidney biopsy, serological examination, and clinical symptoms are the main methods for membranous nephropathy (MN) diagnosis. However, false positives and undetectable biochemical components in the results of optical inspections lead to unsatisfactory diagnostic sensitivity and pose obstacles to pathogenic mechanism analysis. In order to reveal detailed component information of immune complexes of MN, microscopic hyperspectral imaging technology is employed to establish a hyperspectral database of 68 patients with two types of MN. Based on the characteristic of the medical HSI, a novel framework of tensor patch-based discriminative linear regression (TDLR) is proposed for MN classification. Experimental results show that the classification accuracy of the proposed model for MN identification is 98.77%. The combination of tensor-based classifiers and hyperspectral data analysis provides new ideas for the research of kidney pathology, which has potential clinical value for the automatic diagnosis of MN.

Effect of UV-B radiation on growth, flavonoid and podophyllotoxin accumulation, and related gene expression in Sinopodophyllum hexandrum

Sinopodophyllum hexandrum is an alpine medicinal plant that produces the anticancer compound podophyllotoxin (PPT). Although a positive relationship between PPT content and altitude has been proved and low temperature enhances plant growth and PPT accumulation has also been revealed, the role of UV radiation in regulating growth and PPT accumulation is still unclear In this study, morphophysiological traits, metabolites content and related genes expression were investigated by exposing S. hexandrum seedlings to treatment with UV-B radiation. The results showed that the contents of soluble sugars and flavonoids, and the expression levels of genes involved in glycometabolism (XET and β-1,3-glucanase) and flavonoid biosynthesis (PAL,C4H,4CL,CHS1 and DTX41) were enhanced in response to UV-B compared to CK. Moreover, genes involved in stress tolerance (MYB, WRKY,APX3 and EX2) were also upregulated in response to UV-B radiation. Although the whole plant biomass exhibited slightly increased values that depended largely on root development, the contents of chlorophyll and PPT and the expression levels of genes involved in photosynthesis (matK, ndhF,rbcL and ycf5) and PPT biosynthesis (C3H,CCoAMT,CCR,CAD, DPO, PLR,SDH, CPY719A23,OMT3,CYP71CU1,OMT1and 2-ODD) were significantly decreased in response to UV-B compared to CK. It can be concluded that UV-B radiation promotes soluble sugars and flavonoids accumulation, but inhibits PPT biosynthesis in S. hexandrum.

Retrospective Analysis of Clinicopathological Characteristics of Lacrimal Gland Pleomorphic Adenoma and Mechanism of Tumorigenesis by the Imbalance Between Apoptosis and Proliferation

BACKGROUND Lacrimal gland pleomorphic adenoma (LGPA) is the most common clinically benign epithelial tumor of the lacrimal gland and is predominantly comprised of epithelial cells and interstitial components. At present, the exact pathogenesis of LGPA remains unclear. Previous research has indicated that the occurrence of LGPA may be related to excessive cell proliferation. MATERIAL AND METHODS This study observed the clinicopathological characteristics of LGPA and investigated the tumorigenesis mechanism of cell over-proliferation caused by the imbalance between apoptosis and proliferation. A total of 27 cases were collected from the Department of Ophthalmology of the Affiliated Hospital of Chengde Medical University and the Third Medical Center of Chinese PLA General Hospital from April 2017 to November 2019. Hematoxylin-eosin (HE) staining and immunohistochemical staining were used to observe the pathological characteristics and analyze the expression of bcl-2 and bax in the lacrimal gland. RESULTS Compared with normal lacrimal gland tissues, LGPA tumor tissues had obvious changes in pathological morphology. The expression of bcl-2 in LGPA lesion tissues was dramatically higher (P<0.001), the expression of bax was not significantly different between groups (P=0.25), but the ratio of bcl-2/bax was significantly higher in tumor tissues (P=0.01). CONCLUSIONS We found that the lacrimal gland tumor tissues had obvious excessive proliferation in pathomorphology, which revealed the necessity of complete surgical removal of the capsule from the perspective of pathological morphology and provided a theoretical basis for the hypothesis that the imbalance between apoptosis and proliferation could lead to cell hyperproliferation.

Shallow distance-dependent triplet energy migration mediated by endothermic charge-transfer

Conventional wisdom posits that spin-triplet energy transfer (TET) is only operative over short distances because Dexter-type electronic coupling for TET rapidly decreases with increasing donor acceptor separation. While coherent mechanisms such as super-exchange can enhance the magnitude of electronic coupling, they are equally attenuated with distance. Here, we report endothermic charge-transfer-mediated TET as an alternative mechanism featuring shallow distance-dependence and experimentally demonstrated it using a linked nanocrystal-polyacene donor acceptor pair. Donor-acceptor electronic coupling is quantitatively controlled through wavefunction leakage out of the core/shell semiconductor nanocrystals, while the charge/energy transfer driving force is conserved. Attenuation of the TET rate as a function of shell thickness clearly follows the trend of hole probability density on nanocrystal surfaces rather than the product of electron and hole densities, consistent with endothermic hole-transfer-mediated TET. The shallow distance-dependence afforded by this mechanism enables efficient TET across distances well beyond the nominal range of Dexter or super-exchange paradigms.

Identification and fine-mapping of RppCML496, a major QTL for resistance to Puccinia polysora in maize

Southern corn rust (SCR), which is caused by the fungal pathogen Puccinia polysora Underw, is a prevalent foliar disease in maize. Breeding for resistant cultivars is a desirable way for the efficient control of this disease. To identify quantitative trait loci (QTL) for conferring resistance to SCR, a recombinant inbred population including 138 lines (RILs) derived from the SCR-resistant line CML496 and susceptible line Lx9801 was evaluated for phenotypic reaction to SCR in three trials in two locations over 2 years. The population was genotyped with the maize 9.4K SNP Genotyping Array marker platform. A total of 3 QTL were mapped on chromosomes 6, 9 and 10, respectively. One major QTL on chromosome 10 (bin 10.00/10.01), RppCML496, was consistently detected across environments, which explained 43-78% of the total phenotypic variation. Using a fine mapping strategy, we delimited RppCML496 to an interval of 128 Kb. Genome mining of this region suggests two candidate genes, and a NBS-LRR gene is the promising one for RppCML496 against SCR. The tightly linked molecular markers developed in this study can be used for molecular breeding of resistance to SCR in maize.

Natural and human environment interactively drive spread pattern of COVID-19: A city-level modeling study in China

A novel Coronavirus COVID-19 has caused high morbidity and mortality in China and worldwide. A few studies have explored the impact of climate change or human activity on the disease incidence in China or a city. The integrated study concerning environment impact on the emerging disease is rarely reported. Therefore, based on the two-stage modeling study, we investigate the effect of both natural and human environment on COVID-19 incidence at a city level. Besides, the interactive effect of different factors on COVID-19 incidence is analyzed using Geodetector; the impact of effective factors and interaction terms on COVID-19 is simulated with Geographically Weighted Regression (GWR) models. The results find that mean temperature (MeanT), destination proportion in population flow from Wuhan (WH), migration scale (MS), and WH*MeanT, are generally promoting for COVID-19 incidence before Wuhan's shutdown (T1); the WH and MeanT play a determinant role in the disease spread in T1. The effect of environment on COVID-19 incidence after Wuhan's shutdown (T2) includes more factors (including mean DEM, relative humidity, precipitation (Pre), travel intensity within a city (TC), and their interactive terms) than T1, and their effect shows distinct spatial heterogeneity. Interestingly, the dividing line of positive-negative effect of MeanT and Pre on COVID-19 incidence is 8.5°C and 1 mm, respectively. In T2, WH has weak impact, but the MS has the strongest effect. The COVID-19 incidence in T2 without quarantine is also modeled using the developed GWR model, and the modeled incidence shows an obvious increase for 75.6% cities compared with reported incidence in T2 especially for some mega cities. This evidences national quarantine and traffic control take determinant role in controlling the disease spread. The study indicates that both natural environment and human factors integratedly affect the spread pattern of COVID-19 in China.

The synergistic anti-depression effects of different efficacy groups of Xiaoyaosan as demonstrated by the integration of network pharmacology and serum metabolomics

Compatibility investigations are vital but also the most difficult aspect of traditional Chinese medicine (TCM) prescriptions. Previous researches have demonstrated that Xiaoyaosan (XYS) is an effective treatment for depression. However, the compatibility rules of XYS and the underlying mechanisms remain unclear. Herein, we combined network pharmacology and serum metabolomics to investigate the scientific connotations and the compatibility effects of XYS. First, the Traditional Chinese Medicine Systems Pharmacology (TCMSP) and the GeneCards databases were applied to identify the chemical components and the putative targets of XYS, and its efficacy groups. We then analyzed the herb-component-target pathways and constructed PPI networks. Potential pathways were determined by gene ontology (GO) and pathway enrichment analyses. Additionally, a chronic unpredictable mild stress (CUMS) model was applied on rats. A proton nuclear magnetic resonance spectrometry (¹H NMR) based serum metabolomics was then used to identify potential metabolites and the corresponding pathways that were involved in depression and the potential anti-depression effects of XYS and its efficacy groups. A total of 121 components of XYS and 111 targets were associated with depression. Additionally, we screened 105 targets of 24 components in Shugan (SG) group and 106 targets of 95 components in Jianpi (JP) group. 13 targets were common to all three groups. Protein-protein interaction network analysis showed that Caspase-3 and Nitric oxide synthase-3 were nodes that overlapped with proteins known to be associated with depression. Pathway enrichment analysis further indicated that the putative targets of XYS and its efficacy groups mostly participated in pathways associated with cancer. Also, XYS and its efficacy groups significantly reversed abnormalities of serum metabolites and metabolic pathways, but to different degrees. Overall, different efficacy groups of XYS exhibit synergistic anti-depression effects and contribute to the whole prescription against depression. This study shows that the combination of network pharmacology and metabolomics is an effective approach to demonstrate scientific connotations and compatibility of TCMs from a holistic perspective.

Consistency of recommendations and methodological quality of guidelines for the diagnosis and treatment of COVID-19

OBJECTIVE

Since the beginning of the COVID-19 epidemic, a large number of guidelines on diagnosis and treatment of COVID-19 have been developed, but the quality of those guidelines and the consistency of recommendations are unclear. The objective of this study is to evaluate the quality of the diagnosis and treatment guidelines on COVID-19 and analyze the consistency of the recommendations of these guidelines.

METHODS

We searched for guidelines on diagnosis and/or treatment of COVID-19 through PubMed, CBM, CNKI, and WanFang Data, from January 1, 2020 to August 31, 2020. In addition, we also searched official websites of the US CDC, European CDC and WHO, and some guideline collection databases. We included diagnosis and/or treatment guidelines for COVID-19, including rapid advice guidelines and interim guidelines. Two trained researchers independently extracted data and four trained researchers evaluated the quality of the guidelines using the AGREE II instruments. We extracted information on the basic characteristics of the guidelines, guideline development process, and the recommendations. We described the consistency of the direction of recommendations for treatment and diagnosis of COVID-19 across the included guidelines.

RESULTS

A total of 37 guidelines were included. Most included guidelines were assessed as low quality, with only one of the six domains of AGREE II (clarity of presentation) having a mean score above 50%. The mean scores of three domains (stakeholder involvement, the rigor of development and applicability) were all below 30%. The recommendations on diagnosis and treatment were to some extent consistent between the included guidelines. Computed tomography (CT), X-rays, lung ultrasound, RT-PCR, and routine blood tests were the most commonly recommended methods for COVID-19 diagnosis. Thirty guidelines were on the treatment of COVID-19. The recommended forms of treatment included supportive care, antiviral therapy, glucocorticoid therapy, antibiotics, immunoglobulin, extracorporeal membrane oxygenation (ECMO), convalescent plasma, and psychotherapy.

CONCLUSIONS

The methodological quality of currently available diagnosis and treatment guidelines for COVID-19 is low. The diagnosis and treatment recommendations between the included guidelines are highly consistent. The main diagnostic methods for COVID-19 are RT-PCR and CT, with ultrasound as a potential diagnostic tool. As there is no effective treatment against COVID-19 yet, supportive therapy is at the moment the most important treatment option.

TLR4 signaling induces the release of microparticles by tumor cells that regulate inflammatory cytokine IL-6 of macrophages via microRNA let-7b

Tumor cells expressing TLRs is generally recognized to mediate tumor inflammation. However, whether and how tumor TLR signaling pathways negatively regulate tumor inflammation remains unclear. In this report, we find that TLR4 signaling of H22 hepatocarcinoma tumor cells is transduced through MyD88 pathway to actin cytoskeletons, leading to the release of microparticles (MPs), the cellular membrane-derived vesicles. As a result, tumor macrophages take up MPs and acquire MP-contained microRNA let-7b, which attenuates tumor inflammation by targeting proinflammatory cytokine IL-6. Thus, tumor TLR signaling, contrary to the original promoting effect, may play an opposite role in downregulating tumor inflammation through MP pathways.