Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism.

Nowadays, presynaptic dopaminergic positron emission tomography, which assesses deficiencies in dopamine synthesis, storage, and transport, is widely utilized for early diagnosis and differential diagnosis of parkinsonism. This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism. We conducted a thorough literature search using reputable databases such as PubMed and Web of Science. Selection criteria involved identifying peer-reviewed articles published within the last 5 years, with emphasis on their relevance to clinical applications. The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis. Moreover, when employed in conjunction with other imaging modalities and advanced analytical methods, presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker. This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion. In summary, the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials, ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

Impact of Aging on Cardiovascular Diseases: From Chronological Observation to Biological Insights: JACC Family Series.

Cardiovascular disease (CVD) has increasing challenges for human health with an increasingly aging population worldwide, imposing a significant obstacle to the goal of healthy aging. Rapid advancements in our understanding of biological aging process have shed new light on some important insights to aging-related diseases. Although numerous reviews delved into the mechanisms through which biological aging affects CVD and age-related diseases, most of these reviews relied heavily on research related to cellular and molecular processes often observed from animal experiments. Few reviews have provided insights that connect hypotheses regarding the biological aging process with the observed patterns of chronological aging-related impacts on CVD in human populations. The purpose of this review is to highlight some of the major questions in studies of aging-related CVD and provide our perspectives in the context of real-world patterns of CVD with multidimensional information and potential biological insights.

Hospitalization expenses of coronary heart disease inpatients in China: evidence from two hospitals in Ningxia Hui autonomous region.

Aim: The increasing morbidity from coronary health disease (CHD) has imposed a significant social and economic burden in China. We analyzed the factors affecting hospitalization expenses of CHD patients. Design: From 2012 to 2018, data on 16,726 CHD patients were collected from the hospital information system in Ningxia Hui Autonomous Region. Methods: A multiple ordered logistic regression model was used to analyze the factors affecting hospitalization expenses. Results: The average hospitalization expense was RMB30998.26 ± 29890.03. Hospital materials expenses accounted for roughly 60% of total hospitalization costs. The older adult, patients who were male, in critical health status, with longer hospital stays, unemployed, using antibiotics and undergoing an operation without incision had significantly raised hospital expenses, while those with fewer complications, no operations and self-paying for health care had reduced hospitalization costs (p < 0.05). The length of hospital stay played a partial mediator role (p < 0.05). Public contribution: Controlling the increase of medical materials costs and preventing over-consumption of hospital services by insured patients are recommended.

Urolithin A Inhibits Anterior Basolateral Amygdala to Ventral Hippocampal CA1 Circuit to Ameliorate Amyloid-ß-Impaired Social Ability.

Background: Anxiety and social withdrawal are highly prevalent among patients with Alzheimer's disease (AD). However, the neural circuit mechanisms underlying these symptoms remain elusive, and there is a need for effective prevention strategies. Objective: This study aims to elucidate the neural circuitry mechanisms underlying social anxiety in AD. Methods: We utilized 5xFAD mice and conducted a series of experiments including optogenetic manipulation, Tandem Mass Tag-labeled proteome analysis, behavioral assessments, and immunofluorescence staining. Results: In 5xFAD mice, we observed significant amyloid-ß (Aß) accumulation in the anterior part of basolateral amygdala (aBLA). Behaviorally, 6-month-old 5xFAD mice displayed excessive social avoidance during social interaction. Concurrently, the pathway from aBLA to ventral hippocampal CA1 (vCA1) was significantly activated and exhibited a disorganized firing patterns during social interaction. By optogenetically inhibiting the aBLA-vCA1 pathway, we effectively improved the social ability of 5xFAD mice. In the presence of Aß accumulation, we identified distinct changes in the protein network within the aBLA. Following one month of administration of Urolithin A (UA), we observed significant restoration of the abnormal protein network within the aBLA. UA treatment also attenuated the disorganized firings of the aBLA-vCA1 pathway, leading to an improvement in social ability. Conclusions: The aBLA-vCA1 circuit is a vulnerable pathway in response to Aß accumulation during the progression of AD and plays a crucial role in Aß-induced social anxiety. Targeting the aBLA-vCA1 circuit and UA administration are both effective strategies for improving the Aß-impaired social ability.

Tungsten phosphide on nitrogen and phosphorus-doped carbon as a functional membrane coating enabling robust lithium-sulfur batteries.

Lithium-sulfur batteries (LSBs) hold great potential as future energy storage technology, but their widespread application is hampered by the slow polysulfide conversion kinetics and the sulfur loss during cycling. In this study, we detail a one-step approach to growing tungsten phosphide (WP) nanoparticles on the surface of nitrogen and phosphorus co-doped carbon nanosheets (WP@NPC). We further demonstrate that this material provides outstanding performance as a multifunctional separator in LSBs, enabling higher sulfur utilization and exceptional rate performance. These excellent properties are associated with the abundance of lithium polysulfide (LiPS) adsorption and catalytic conversion sites and rapid ion transport capabilities. Experimental data and density functional theory calculations demonstrate tungsten to have a sulfophilic character while nitrogen and phosphorus provide lithiophilic sites that prevent the loss of LiPSs. Furthermore, WP regulates the LiPS catalytic conversion, accelerating the Li-S redox kinetics. As a result, LSBs containing a polypropylene separator coated with a WP@NPC layer show capacities close to 1500 mAh/g at 0.1C and coulombic efficiencies above 99.5 % at 3C. Batteries with high sulfur loading, 4.9 mg cm-2, are further produced to validate their superior cycling stability. Overall, this work demonstrates the use of multifunctional separators as an effective strategy to promote LSB performance.

Bidirectional regulation of levodopa-induced dyskinesia by a specific neural ensemble in globus pallidus external segment.

Levodopa-induced dyskinesia (LID) is an intractable motor complication arising in Parkinson's disease with the progression of disease and chronic treatment of levodopa. However, the specific cell assemblies mediating dyskinesia have not been fully elucidated. Here, we utilize the activity-dependent tool to identify three brain regions (globus pallidus external segment [GPe], parafascicular thalamic nucleus, and subthalamic nucleus) that specifically contain dyskinesia-activated ensembles. An intensity-dependent hyperactivity in the dyskinesia-activated subpopulation in GPe (GPeTRAPed in LID) is observed during dyskinesia. Optogenetic inhibition of GPeTRAPed in LID significantly ameliorates LID, whereas reactivation of GPeTRAPed in LID evokes dyskinetic behavior in the levodopa-off state. Simultaneous chemogenetic reactivation of GPeTRAPed in LID and another previously reported ensemble in striatum fully reproduces the dyskinesia induced by high-dose levodopa. Finally, we characterize GPeTRAPed in LID as a subset of prototypic neurons in GPe. These findings provide theoretical foundations for precision medication and modulation of LID in the future.

MR-based radiomics predictive modelling of EGFR mutation and HER2 overexpression in metastatic brain adenocarcinoma: a two-centre study.

OBJECTIVES: Magnetic resonance (MR)-based radiomics features of brain metastases are utilised to predict epidermal growth factor receptor (EGFR) mutation and human epidermal growth factor receptor 2 (HER2) overexpression in adenocarcinoma, with the aim to identify the most predictive MR sequence. METHODS: A retrospective inclusion of 268 individuals with brain metastases from adenocarcinoma across two institutions was conducted. Utilising T1-weighted imaging (T1 contrast-enhanced [T1-CE]) and T2 fluid-attenuated inversion recovery (T2-FLAIR) sequences, 1,409 radiomics features were extracted. These sequences were randomly divided into training and test sets at a 7:3 ratio. The selection of relevant features was done using the least absolute shrinkage selection operator, and the training cohort's support vector classifier model was employed to generate the predictive model. The performance of the radiomics features was evaluated using a separate test set. RESULTS: For contrast-enhanced T1-CE cohorts, the radiomics features based on 19 selected characteristics exhibited excellent discrimination. No significant differences in age, sex, and time to metastasis were observed between the groups with EGFR mutations or HER2 + and those with wild-type EGFR or HER2 (p > 0.05). Radiomics feature analysis for T1-CE revealed an area under the curve (AUC) of 0.98, classification accuracy of 0.93, sensitivity of 0.92, and specificity of 0.93 in the training cohort. In the test set, the AUC was 0.82. The 19 radiomics features for the T2-FLAIR sequence showed AUCs of 0.86 in the training set and 0.70 in the test set. CONCLUSIONS: This study developed a T1-CE signature that could serve as a non-invasive adjunctive tool to determine the presence of EGFR mutations and HER2 + status in adenocarcinoma, aiding in the direction of treatment plans. CLINICAL RELEVANCE STATEMENT: We propose radiomics features based on T1-CE brain MR sequences that are both evidence-based and non-invasive. These can be employed to guide clinical treatment planning in patients with brain metastases from adenocarcinoma.

Atomistic Insights into Nucleation of Ferroelastic Domains in PbTiO3.

Understanding the nucleation mechanism of domains is essential for domain engineering of perovskite ferroelectric materials. We proposed and examined atomistic details for nucleating ferroelastic (FS) domains by integrating topological analysis and first-principles calculations. FS domains are crystallographically treated as deformation twins. The conventional shear-shuffle nucleation mechanism under simple shear deformation is ruled out because the 1-layer elementary twinning disconnection (TD) cannot nucleate and glide in a perfect matrix. Thus, the pure-shuffle nucleation mechanism under pure shear deformation is proposed due to kinetically favored atomic shuffling. The coherency stress associated with the coherent nucleus is relaxed via forming misfit dislocations, accompanied by formation and sharpening of diffused (110)m∥(110)d domain walls (DWs). The sharp DWs enable growth of the FS nucleus through successive nucleation and gliding of TDs. These findings enrich the knowledge of domain behavior in perovskite ferroelectric materials.

A Piecewise Design Approach to Engineering a Miniature ACE2 Mimic to Bind SARS-CoV-2.

As the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues its global spread, the exploration of novel therapeutic and diagnostic strategies is still needed. The virus enters host cells by binding the angiotensin-converting enzyme 2 (ACE2) receptor through the spike protein. Here, we develop an engineered, small, stable, and catalytically inactive version of ACE2, termed miniature ACE2 (mACE2), designed to bind the spike protein with high affinity. Employing a magnetic nanoparticle-based assay, we harnessed the strong binding affinity of mACE2 to develop a sensitive and specific platform for the detection or neutralization of SARS-CoV-2. Our findings highlight the potential of engineered mACE2 as a valuable tool in the fight against SARS-CoV-2. The success of developing such a small reagent based on a piecewise molecular design serves as a proof-of-concept approach for the rapid deployment of such agents to diagnose and fight other viral diseases.

Polyhydroxy structure orchestrates the intrinsic antibacterial property of acrylamide hydrogel as a versatile wound-healing dressing.

Hydrogel is considered as a promising candidate for wound dressing due to its tissue-like flexibility, good mechanical properties and biocompatibility. However, traditional hydrogel dressings often fail to fulfill satisfied mechanical, antibacterial, and biocompatibility properties simultaneously, due to the insufficient intrinsic bactericidal efficacy and the addition of external antimicrobial agents. In this paper, hydroxyl-contained acrylamide monomers, N-Methylolacrylamide (NMA) and N-[Tris (hydroxymethyl)methyl] acrylamide (THMA), are employed to prepare a series of polyacrylamide hydrogel dressings xNMA-yTHMA, where x and y represent the mass fractions of NMA and THMA in the hydrogels. We have elucidated that the abundance of hydroxyl groups determines the antibacterial effect of the hydrogels. Particularly, hydrogel 35NMA-5THMA exhibits excellent mechanical properties, with high tensile strength of 259 kPa and large tensile strain of 1737%. Furthermore, the hydrogel dressing 35NMA-5THMA demonstrates remarkable inherent antibacterial without exogenous antimicrobial agents owing to the existence of abundant hydroxyl groups. Besides, hydrogel dressing 35NMA-5THMA possesses excellent biocompatibility, in view of marginal cytotoxicity, low hemolysis ratio, and negligible inflammatory response and organ toxicity to mice during treatment. Encouragingly, hydrogel 35NMA-5THMA drastically promote the healing of bacteria-infected wound in mice. This study has revealed the importance of polyhydroxyl in the antibacterial efficiency of hydrogels and provided a simplified strategy to design wound healing dressings with translational potential.

High-Entropy Polymer Electrolytes Derived from Multivalent Polymeric Ligands for Solid-State Lithium Metal Batteries with Accelerated Li+ Transport.

Solid-state polymer-based electrolytes (SSPEs) exhibit great possibilities in realizing high-energy-density solid-state lithium metal batteries (SSLMBs). However, current SSPEs suffer from low ionic conductivity and unsatisfactory interfacial compatibility with metallic Li because of the high crystallinity of polymers and sluggish Li+ movement in SSPEs. Herein, differing from common strategies of copolymerization, a new strategy of constructing a high-entropy SSPE from multivariant polymeric ligands is proposed. As a protocol, poly(vinylidene fluoride-co-hexafluoropropylene) (PH) chains are grafted to the demoed polyethylene imine (PEI) with abundant -NH2 groups via a click-like reaction (HE-PEIgPHE). Compared to a PH-based SSPE, our HE-PEIgPHE shows a higher modulus (6.75 vs 5.18 MPa), a higher ionic conductivity (2.14 × 10-4 vs 1.03 × 10-4 S cm-1), and a higher Li+ transference number (0.55 vs 0.42). A Li|HE-PEIgPHE|Li cell exhibits a long lifetime (1500 h), and a Li|HE-PEIgPHE|LiFePO4 cell delivers an initial capacity of 160 mAh g-1 and a capacity retention of 98.7%, demonstrating the potential of our HE-PEIgPHE for the SSLMBs.

Superfast Zincophilic Ion Conductor Enables Rapid Interfacial Desolvation Kinetics for Low-Temperature Zinc Metal Batteries.

Low-temperature rechargeable aqueous zinc metal batteries (AZMBs) as highly promising candidates for energy storage are largely hindered by huge desolvation energy barriers and depressive Zn2+ migration kinetics. In this work, a superfast zincophilic ion conductor of layered zinc silicate nanosheet (LZS) is constructed on a metallic Zn surface, as an artificial layer and ion diffusion accelerator. The experimental and simulation results reveal the zincophilic ability and layer structure of LZS not only promote the desolvation kinetics of [Zn(H2O)6]2+ but also accelerate the Zn2+ transport kinetics across the anode/electrolyte interface, guiding uniform Zn deposition. Benefiting from these features, the LZS-modified Zn anodes showcase long-time stability (over 3300 h) and high Coulombic efficiency with ≈99.8% at 2 mA cm-2, respectively. Even reducing the environment temperature down to 0 °C, ultralong cycling stability up to 3600 h and a distinguished rate performance are realized. Consequently, the assembled Zn@LZS//V2O5-x full cells deliver superior cyclic stability (344.5 mAh g-1 after 200 cycles at 1 A g-1) and rate capability (285.3 mAh g-1 at 10 A g-1) together with a low self-discharge rate, highlighting the bright future of low-temperature AZMBs.

The in vitro mechanism of Vaspinregulates the proliferation and steroidogenesis of rat lutein cells.

OBJECTIVE: Stable luteal cell function is an important prerequisite for reproductive ability and embryonic development. However, luteal insufficiency seriously harms couples who have the desire to have a pregnancy, and the most important thing is that there is no complete solution. In addition, Vaspin has been shown to have regulatory effects on luteal cells, but the complex mechanisms involved have not been fully elucidated. Therefore, this study aimed to explore the effect of Vaspin on rat luteal cells and its mechanism. METHODS: Granulosa lutein cells separated from the ovary of female rats were incubated for 24h with gradient concentrations of Vaspin, and granulosa lutein cells incubated with 0.5% bovine serum albumin were used as controls. The proliferation, apoptosis, angiogenesis, progesterone (P4) and estradiol (E2) were detected by CCK-8, Anneixn-FITC/PI staining, angiogenesis experiment and ELISA. Western blot was applied to observe the expression levels of proteins related to cell proliferation, apoptosis, angiogenesis and MEK/MAPK signaling pathway. RESULTS: Compared with the Control group, Vaspin could significantly up-regulate the proliferation of granulosa lutein cells and reduce the apoptosis. Moreover, Vaspin promoted the angiogenesis of granulosa lutein cells and the production of P4 and E2 in a concentration-dependent manner. Furthermore, Vaspin up-regulated the CyclinD1, CyclinB1, Bcl2, VEGFA and FGF-2 expression in granulosa lutein cells, and down-regulated the level of Bax. Also, Vaspin increased the p-MEK1 and p-p38 levels. CONCLUSION: Vaspin can up-regulate the proliferation and steroidogenesis of rat luteal cells and reduce apoptosis, which may be related to the influence of MEK/MAPK activity.

The efficacy and safety of adding PD-1 blockade to induction chemotherapy and concurrent chemoradiotherapy (IC-CCRT) for locoregionally advanced nasopharyngeal carcinoma: an observational, propensity score-matched analysis.

BACKGROUND: Despite the success of PD-1 blockade in recurrent/metastatic nasopharyngeal carcinoma (NPC), its effect for locoregionally advanced NPC (LANPC) remains unclear. This study aimed to evaluate the benefit of adding PD-1 blockade to the current standard treatment (gemcitabine and cisplatin IC  plus cisplatin CCRT ) for LANPC patients. METHODS: From January 2020 to November 2022, 347 patients with non-metastatic high-risk LANPC (stage III-IVA, excluding T3-4N0) were included. Of the 347 patients, 268 patients were treated with standard treatment (IC-CCRT), and 79 received PD-1 blockade plus IC-CCRT (PD-1 group). For the PD-1 group, PD-1 blockade was given intravenously once every 3 weeks for up to 9 cycles (3 induction and 6 adjuvant). The primary endpoint was disease-free survival (DFS) (i.e. freedom from local/regional/distant failure or death). The propensity score matching (PSM) with the ratio of 1:2 was performed to control confounding factors. RESULTS: After PSM analysis, 150 patients receiving standard treatment and 75 patients receiving additional PD-1 blockade remained in the current analysis. After three cycles of IC, the PD-1 group had significantly higher rates of complete response (defined as disappearance of all target lesions; 24% vs. 9%; P = 0.006) and complete biological response (defined as undetectable cell-free Epstein-Barr virus DNA, cfEBV DNA; 79% vs. 65%; P = 0.046) than that in the standard group. And the incidence of grade 3-4 toxicity during IC was 47% in the PD-1 group and 41% in the standard group, with no significant difference (P = 0.396). During follow-up period, additional PD-1 blockade to standard treatment improved 3-year DFS from 84 to 95%, with marginal statistical significance (HR, 0.28; 95%CI, 0.06-1.19; P = 0.064). CONCLUSION: Additiaonl PD-1 blockade to gemcitabine and cisplatin IC and adjuvant treatment results in significant improvement in tumor regression, cfEBV DNA clearance, superior DFS, and comparable toxicity profiles in high-risk LANPC patients.

Nonlinear dynamics of postural control system under visual-vestibular habituation balance practice: evidence from EEG, EMG and center of pressure signals.

Human postural control system is inherently complex with nonlinear interaction among multiple subsystems. Accordingly, such postural control system has the flexibility in adaptation to complex environments. Previous studies applied complexity-based methods to analyze center of pressure (COP) to explore nonlinear dynamics of postural sway under changing environments, but direct evidence from central nervous system or muscular system is limited in the existing literature. Therefore, we assessed the fractal dimension of COP, surface electromyographic (sEMG) and electroencephalogram (EEG) signals under visual-vestibular habituation balance practice. We combined a rotating platform and a virtual reality headset to present visual-vestibular congruent or incongruent conditions. We asked participants to undergo repeated exposure to either congruent (n = 14) or incongruent condition (n = 13) five times while maintaining balance. We found repeated practice under both congruent and incongruent conditions increased the complexity of high-frequency (0.5-20 Hz) component of COP data and the complexity of sEMG data from tibialis anterior muscle. In contrast, repeated practice under conflicts decreased the complexity of low-frequency (<0.5 Hz) component of COP data and the complexity of EEG data of parietal and occipital lobes, while repeated practice under congruent environment decreased the complexity of EEG data of parietal and temporal lobes. These results suggested nonlinear dynamics of cortical activity differed after balance practice under congruent and incongruent environments. Also, we found a positive correlation (1) between the complexity of high-frequency component of COP and the complexity of sEMG signals from calf muscles, and (2) between the complexity of low-frequency component of COP and the complexity of EEG signals. These results suggested the low- or high-component of COP might be related to central or muscular adjustment of postural control, respectively.

C-176 reduces inflammation-induced pain by blocking the cGAS-STING pathway in microglia.

OBJECTIVE: Inflammatory pain, is caused by lesions or diseases of the somatosensory tissue, is a prevalent chronic condition that profoundly impacts the quality of life. However, clinical treatment for this type of pain remains limited. Traditionally, the stimulation of microglia and subsequent inflammatory reactions are considered crucial elements to promote the worsening of inflammatory pain. Recent research has shown the crucial importance of the cGAS-STING pathway in promoting inflammation. It is still uncertain if the cGAS-STING pathway plays the role in the fundamental cause of inflammatory pain. We aim to explore the treatment of inflammatory pain by interfering with cGAS-STING signaling pathway. METHODS: In this study, we established an inflammatory pain model by CFA into the plantar of mice. Activation of microglia, various inflammatory factors and cGAS-STING protein in the spinal dorsal horn were evaluated. Immunofluorescence staining was used to observe the cellular localization of cGAS and STING. The cGAS-STING pathway proteins expression and mRNA expression of indicated microglial M1/M2 phenotypic markers in the BV2 microglia were detected. STING inhibitor C-176 was intrathecal injected into mice with inflammatory pain, and the pain behavior and microglia were observed. RESULTS: This research showed that injecting CFA into the left hind paw of mice caused mechanical allodynia and increased inflammation in the spine. Our research results suggested that the cGAS-STING pathway had a function in the inflammation mediated by microglia in the spinal cord dorsal horn. Blocking the cGAS-STING pathway using STING antagonists (C-176) led to reduced release of inflammatory factors and prevented M1 polarization of BV2 microglia in a laboratory setting. Additionally, intrathecal administration of C-176 reduced the allodynia in CFA treated mice. CONCLUSION: Our results suggest that inhibiting microglial polarization through the cGAS-STING pathway represents a potential novel therapeutic strategy for inflammatory pain.

Temporal niche partitioning among sympatric wild and domestic ungulates between warm and cold seasons.

The coexistence of sympatric species with similar ecological niches has been a central issue in ecology. Clarifying the daily activity patterns of sympatric wild ungulates can help understand their temporal niche differentiation and the mechanisms of coexistence, providing information for their conservation. The Baotianman National Nature Reserve in northern China is rich in wild ungulates, but little is known about the daily activity patterns of wild ungulates in the area, making it difficult to develop effective conservation strategies. We studied five representative wild ungulates (i.e. forest musk deer, Chinese goral, Reeve's muntjac, Siberian roe deer, and wild boar) of the region using camera-trapping data, focusing on the seasonal daily activity patterns and effects of seasonal grazing of domestic sheep, to reveal their coexistence based on temporal ecological niche differentiation. Comparative analyses of the seasonal daily activity showed that forest musk deer exhibited a single-peak activity in the warm season. Other ungulates exhibited multipeak activity. All five ungulates differed significantly in daily activity patterns. Notably, wild boar and Reeve's muntjac showed high overlap coefficients between the cold and warm seasons. In both cold and warm seasons, the five wild ungulates and domestic sheep displayed low overlap in their daily activity rhythms potentially indicating temporal ecological niche differentiation. The results suggest that temporal isolation might be a strategy for wild ungulates to avoid domestic sheep and reduce interspecific competition, and that temporal ecological niche differentiation potentially promoted the coexistence among the studied sympatric ungulates. This understanding may provide new insights for the development of targeted conservation strategies.

The loss of dissolved organic matter from biological soil crust at various successional stages under rainfall of different intensities: Insights into the changes of molecular components at different rainfall stages.

Biological soil crusts (BSCs) are typical covers in arid and semiarid regions. The dissolved organic matter (DOM) of BSCs can be transported to various aquatic ecosystems by rainfall-runoff processes. However, the spatiotemporal variation in quality and quantity of DOM in runoff remains unclear. Herein, four kinds of runoff plots covered by four successional stages of BSCs were set up on slopes, including bare runoff plot (BR), cyanobacteria crust covered runoff plot (CR), mixed crust covered runoff plot (MIR), and moss crust covered runoff plot (MOR). The quantity and quality of DOM in runoff during rainfall was investigated based on the stimulated rainfall experiments combined with optical spectroscopy and ultra-high resolution mass spectrometry analyses. The results showed that the DOM concentrations (i.e., 0.30 to 45.25 mg L-1) in runoff followed the pattern of MOR>MIR>CR>BR, and they were exponentially decreased with rainfall duration. The DOM loss rate of BR (8.26 to 11.64 %) was significantly greater than those of CR, MIR, and MOR (0.84 to 3.22 %). Highly unsaturated compounds (HUCs), unsaturated aliphatic compounds (UACs), saturated compounds (SCs), and peptide-like compounds (PLCs) were the dominated compounds of the water extractable DOM from the original soils. Thereinto, PLCs and UACs were more easily leached into runoff during rainfall. The relatively intensity of HUCs in runoff generally decreased with rainfall duration, while the relatively intensities of UACs, PLCs, and SCs slightly increased with rainfall duration. These findings suggested that the DOM loss rate was effectively decreased with the successional of BSCs during rainfall; meanwhile, some labile compounds (e.g., PLCs and UACs) were transported into various aquatic ecosystems by rainfall-runoff processes.