The effect of high-volume intraoperative fluid administration on outcomes among pediatric patients undergoing living donor liver transplantation.

BACKGROUND: Pediatric patients undergoing liver transplantation are particularly susceptible to complications arising from intraoperative fluid management strategies. Conventional liberal fluid administration has been challenged due to its association with increased perioperative morbidity. This study aimed to assess the impact of intraoperative high-volume fluid therapy on pediatric patients who are undergoing living donor liver transplantation (LDLT). METHODS: Conducted at the Children's Hospital of Chongqing Medical University from March 2018 to April 2021, this retrospective study involved 90 pediatric patients divided into high-volume and non-high-volume fluid administration groups based on the 80th percentile of fluid administered. We collected the perioperative parameters and postoperative information of two groups. Multivariable logistic regression was utilized to assess the association between estimated blood loss (EBL) and high-volume FA. Kaplan-Meier survival analysis was used to compare patient survival after pediatric LDLT. RESULTS: Patients in the high-volume FA group received a higher EBL and longer length of stay than that in the non-high-volume FA group. Multivariate logistic regression analysis indicated that hours of maintenance fluids and fresh frozen plasma were significantly associated risk factors for the occurrence of EBL during pediatric LDLT. In addition, survival analysis showed no significant differences in one-year mortality between the groups. CONCLUSIONS: High-volume fluid administration during LDLT is linked with poorer intraoperative and postoperative outcomes among pediatric patients. These findings underscore the need for more conservative fluid management strategies in pediatric liver transplantations to enhance recovery and reduce complications.

[Effect of 2-phenylethyl-beta-glucopyranoside isolated from Huaizhong No. 1 Rehmannia glutinosa on hypoxic pulmonary hypertension by regulating PI3K/Akt/m TOR/HIF-1α pathway].

The study investigated the protective effect and mechanism of 2-phenylethyl-beta-glucopyranoside(Phe) from Huaizhong No.1 Rehmannia glutinosa on hypoxic pulmonary hypertension(PH), aiming to provide a theoretical basis for clinical treatment of PAH. Male C57BL/6N mice were randomly divided into normal group, model group, positive drug(bosentan, 100 mg·kg~(-1)) group, and low-and high-dose Phe groups(20 and 40 mg·kg~(-1)). Except for the normal group, all other groups were continuously subjected to model induction in a 10% hypoxic environment for 5 weeks, with oral administration for 14 days starting from the 3rd week. The cardiopulmonary function, right ventricular pressure, cough and asthma index, lung injury, cell apoptosis, oxidative stress-related indicators, immune cells, and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/hypoxic inducible factor 1α(HIF-1α) pathway-related proteins or mRNA levels were examined. Furthermore, hypoxia-induced pulmonary arterial smooth muscle cell(PASMC) were used to further explore the mechanism of Phe intervention in PH combined with PI3K ago-nist(740Y-P). The results showed that Phe significantly improved the cardiopulmonary function of mice with PH, decreased right ventricular pressure, cough and asthma index, and lung injury, reduced cell apoptosis, oxidative stress-related indicators, and nuclear levels of phosphorylated Akt(p-Akt) and phosphorylated mTOR(p-mTOR), inhibited the expression levels of HIF-1α and PI3K mRNA and proteins, and maintained the immune cell homeostasis in mice. Further mechanistic studies revealed that Phe significantly reduced the viability and migration ability of hypoxia-induced PASMC, decreased the expression of HIF-1α and PI3K proteins and nuc-lear levels of p-Akt and p-mTOR, and this effect was blocked by 740Y-P. Therefore, it is inferred that Phe may exert anti-PH effects by alleviating the imbalance of oxidative stress and apoptosis in lung tissues and regulating immune levels, and its mechanism may be related to the regulation of the PI3K/Akt/mTOR/HIF-1α pathway. This study is expected to provide drug references and research ideas for the treatment of PH.

An LC-MS/MS method for the determination of Lifitegrast in human plasma and tear and its application in the pharmacokinetic study.

Aim: A new, selective and simple UPLC-MS/MS method was developed and validated for the determination of lifitegrast in human plasma and tear in order to obtain PK data. Materials & methods: Lifitegrast-d4 solutions were added in the samples, and then were extracted and transferred to a UPLC vial. Results: The respective working ranges were 25.00-2000.00 pg/ml in plasma and 4.00-1000.00 µg/ml in tear. The fully validated method complied with existing regulatory criteria for accuracy and precision, recovery, etc. It was applied to plasma and tear samples, which were from a clinical study, successfully. Conclusion: This method is useful in the evaluation of lifitegrast in plasma and tear.

[Box: see text].

Microbial communities and functions are structured by vertical geochemical zones in a northern peatland.

Northern peatlands are important carbon pools; however, differences in the structure and function of microbiomes inhabiting contrasting geochemical zones within these peatlands have rarely been emphasized. Using 16S rRNA gene sequencing, metagenomic profiling, and detailed geochemical analyses, we investigated the taxonomic composition and genetic potential across various geochemical zones of a typical northern peatland profile in the Changbai Mountains region (Northeastern China). Specifically, we focused on elucidating the turnover of organic carbon, sulfur (S), nitrogen (N), and methane (CH4). Three geochemical zones were identified and characterized according to porewater and solid-phase analyses: the redox interface (<10 cm), shallow peat (10-100 cm), and deep peat (>100 cm). The redox interface and upper shallow peat demonstrated a high availability of labile carbon, which decreased toward deeper peat. In deep peat, anaerobic respiration and methanogenesis were likely constrained by thermodynamics, rather than solely driven by available carbon, as the acetate concentrations reached 90 µmol·L-1. Both the microbial community composition and metabolic potentials were significantly different (p < 0.05) among the redox interface, shallow peat, and deep peat. The redox interface demonstrated a close interaction between N, S, and CH4 cycling, mainly driven by Thermodesulfovibrionia, Bradyrhizobium, and Syntrophorhabdia metagenome-assembled genomes (MAGs). The archaeal Bathyarchaeia were indicated to play a significant role in the organic carbon, N, and S cycling in shallow peat. Although constrained by anaerobic respiration and methanogenesis, deep peat exhibited a higher metabolic potential for organic carbon degradation, primarily mediated by Acidobacteriota. In terms of CH4 turnover, subsurface peat (10-20 cm) was a CH4 production hotspot, with a net turnover rate of ∼2.9 nmol·cm-3·d-1, while the acetoclastic, hydrogenotrophic, and methylotrophic methanogenic pathways all potentially contributed to CH4 production. The results of this study improve our understanding of biogeochemical cycles and CH4 turnover along peatland profiles.

Advances in immunotherapy of M2 macrophages and gastrointestinal stromal tumor.

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal-derived tumors of the GI tract. They can occur throughout the GI tract, and the survival time of some patients can be improved by first-line targeted therapy with imatinib. However, there are some limitations with imatinib treatment. Immunotherapy for GIST has attracted much attention in recent years, and as one of the most abundant cells in the GIST microenvironment, M2 macrophages play an important role in disease progression. They have unique anti-inflammatory and pro-tumorigenic effects and are one target for immunotherapy. This review summarizes the connection between different factors and the programmed death receptor-1/programmed death ligand-1 pathway and M2 macrophages to reactivate or enhance anti-tumor immunity and improve imatinib efficacy, and to provide new ideas for GIST immunotherapy.

Genetic Algorithm-Based Cooperative Coding and Caching Data Dissemination Scheme in Multi-UAV-Enabled Internet of Vehicles.

Unmanned Aerial Vehicles (UAVs) have emerged as efficient tools in disaster-stricken areas, facilitating efficient data dissemination for post-disaster rescue operations. However, the limited onboard energy of UAVs imposes significant constraints on their operational lifespan, thereby presenting substantial challenges for efficient data dissemination. Therefore, this work investigates a data dissemination scheme to enhance the UAVs' bandwidth efficiency in multi-UAV-enabled Internet of Vehicles, thereby reducing UAVs' energy consumption and improving overall system performance when UAVs hover along designated flight trajectories for data dissemination. Specifically, first, we present a software-defined network-based framework for data dissemination in multi-UAV-enabled IoV. According to this framework, we formulate a problem called C2BS (Coding-based Cooperative Broadcast Scheduling) that focuses on optimizing the UAVs' bandwidth efficiency by leveraging the combined benefits of coding and caching. Furthermore, we demonstrate the NP-hardness of the C2BS problem by employing a polynomial time reduction technique on the simultaneous matrix completion problem. Then, inspired by the benefits offered by genetic algorithms, we propose a novel approach called the Genetic algorithm-based Cooperative Scheduling (GCS) algorithm to address the C2BS problem. This approach encompasses a coding scheme for representing individuals, a fitness function for assessing individuals, operators (i.e., crossover and mutation) for generating offspring, a local search technique to enhance search performance, and a repair operator employed to rectify infeasible solutions. Additionally, we present an analysis of the time complexity for the GCS algorithm. Finally, we present a simulation model to evaluate the performance. Experimental findings provide evidence of the excellence of the proposed scheme.

Insights into COVID-19 epidemiology and control from temporal changes in serial interval distributions in Hong Kong.

The serial interval distribution is used to approximate the generation time distribution, an essential parameter to infer the transmissibility (${R}_t$) of an epidemic. However, serial interval distributions may change as an epidemic progresses. We examined detailed contact tracing data on laboratory-confirmed cases of COVID-19 in Hong Kong during the five waves from January 2020 to July 2022. We reconstructed the transmission pairs and estimated time-varying effective serial interval distributions and factors associated with longer or shorter intervals. Finally, we assessed the biases in estimating transmissibility using constant serial interval distributions. We found clear temporal changes in mean serial interval estimates within each epidemic wave studied and across waves, with mean serial intervals ranged from 5.5 days (95% CrI: 4.4, 6.6) to 2.7 (95% CrI: 2.2, 3.2) days. The mean serial intervals shortened or lengthened over time, which were found to be closely associated with the temporal variation in COVID-19 case profiles and public health and social measures and could lead to the biases in predicting ${R}_t$. Accounting for the impact of these factors, the time-varying quantification of serial interval distributions could lead to improved estimation of ${R}_t$, and provide additional insights into the impact of public health measures on transmission.

The stray light induced redshift of absorption peaks of inorganic anions in the far ultraviolet region-an "artifact".

In the analytical process of spectrophotometry, the prerequisite for accurate qualitative and quantitative analysis is obtaining the intrinsic spectra of the analyte. However, the intrinsic properties of spectra can sometimes be masked by easily overlooked non-intrinsic factors, such as those from measuring instruments, leading to erroneous spectral identification. In this study, we documented an unusual redshift phenomenon in the far ultraviolet spectral region. With a spectrophotometer under the nitrogen atmosphere, we selected 14 representative inorganic anions and investigated their absorption spectral behaviors at different optical pathlengths and concentrations. It was intriguing to observe that the absorption peaks with maximum absorption wavelengths below a watershed wavelength of 200 nm underwent a redshift as pathlength and concentration increased, while those above 200 nm did not exhibit a significant redshift phenomenon. In-depth formula simulations and experimental verifications demonstrated that this peculiar spectral behavior was caused by unavoidable stray light in the spectrophotometer. Some methodological and instrumental recommendations are given in the paper. Our study results may serve as a reminder to carefully identify non-intrinsic phenomena when studying absorption spectra in the far ultraviolet region, and provide guidance on spectral corrections in scientific research and practical applications.

Discovering Potential Mechanisms of Intervertebral Disc Disease Using Systematic Mendelian Randomization of Human Circulating Immunocytomics.

BACKGROUND: Although intervertebral disc degeneration (IVDD) is a critical factor in many spine-related diseases and has an extremely high prevalence in the aging population, the potential pathogenesis remains to be clarified entirely. Immune cells have been found to perform an essential function during the onset and progression of IVDD in recent years. Therefore, we explored the association between immune cell characteristics and IVDD through Mendelian randomization (MR) analysis and further delved into the mediating role of potential metabolites. METHODS: Based on the MR analysis, the association of 731 immune cell phenotypes and 1400 metabolites on IVDD were assessed. Single nucleotide polymorphisms were closely associated the expression levels of immune cell characteristics and the concentrations of metabolites and have been used as instrumental variables for deducing them as risk factors or protective factors for IVDD. In addition, mediation analyses have been performed to identify potential metabolite mediators between immune cell characteristics and IVDD. RESULTS: MR analysis identified 27 immune cell phenotypes and 79 metabolites significantly associated with IVDD. In addition, mediation analysis was performed by selecting the immune cell phenotype that most significantly increased the risk of IVDD - CD86 on monocytes. A total of 4 metabolite-mediated mediation relationships were revealed (3 b-hydroxy-5-cholenoic acid, X-22509, N-acetyl-L-glutamine, and N2-acetyl, N6, N6-dimethyllysine). CONCLUSIONS: The findings of this analysis identified underlying association between immune cell phenotypes, metabolite, and IVDD that may serve as predictive and prognostic clinical biomarkers and benefit IVDD pathogenesis research.

[Regulatory effect of Tingli Dazao Xiefei Decoction on asthmatic rats by urine metabolomics].

Urine metabolomics based on ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UHPLC-Q-TOF-MS) was utilized to investigate the metabolic regulation mechanism of Tingli Dazao Xiefei Decoction(TLDZ) in rats with allergic asthma. SD male rats were divided into a normal group, a model group, a dexamethasone group, and a TLDZ group. The allergic asthma model was established by intraperitoneal injection of ovalbumin(OVA) to induce allergy, combined with atomization excitation. Urine metabolites from all rats were collected by UHPLC-Q-TOF-MS. The metabolic profiles of rats in each group were built by principal component analysis(PCA). Besides, the differential metabolites between the model group and the TLDZ group were selected by orthogonal partial least squares discriminant analysis(OPLS-DA), t-test(P<0.05), and variable importance in the projection(VIP) values of more than 3. The differential metabolites were identified through HMDB, METLIN, and other online databa-ses. Heat maps and clustering analysis for relative quantitative information of biomarkers in each group were drawn by MeV 4.8.0 software. Finally, MetaboAnalyst, MBRole, and KEGG databases were used to enrich related metabolic pathways and construct metabolic networks. The result demonstrated that TLDZ could effectively regulate the disordered urine metabolic profiles of asthmatic rats. Combined with multivariate statistical analysis and online databases, a total of 45 differential metabolites with significant changes(P<0.05) between the model group and the TLDZ group were screened out. Metabolic pathways including histidine metabolism, tryptophan metabolism, and arginine and proline metabolism were enriched. TLDZ could improve asthma by regulating related metabolic pathways and interfering with pathological processes such as immune homeostasis airway inflammation. The study investigates the molecular mechanism of anti-asthma of TLDZ from the perspective of urine metabolomics, and combined with previous pharmacological studies, it provides a scientific basis for the clinical development and application of TLDZ in the treatment of asthma.

PCSK9 inhibitors and osteoporosis: mendelian randomization and meta-analysis.

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors represent an effective strategy for reducing cardiovascular disease risk. Yet, PCSK9's impact on osteoporosis remains unclear. Hence, we employed Mendelian randomization (MR) analysis for examining PCSK9 inhibitor effects on osteoporosis. METHODS: Single nucleotide polymorphisms (SNPs) for 3-hydroxy-3-methylglutaryl cofactor A reductase (HMGCR) and PCSK9 were gathered from available online databases for European pedigrees. Four osteoporosis-related genome-wide association studies (GWAS) data served as the main outcomes, and coronary artery disease (CAD) as a positive control for drug-targeted MR analyses. The results of MR analyses examined by sensitivity analyses were incorporated into a meta-analysis for examining causality between PCSK9 and HMGCR inhibitors and osteoporosis. RESULTS: The meta-analysis involving a total of 1,263,102 subjects, showed that PCSK9 inhibitors can increase osteoporosis risk (P < 0.05, I2, 39%). However, HMGCR inhibitors are not associated with osteoporosis risk. Additionally, a replication of the analysis was conducted with another exposure-related GWAS dataset, which led to similar conclusions. CONCLUSION: PCSK9 inhibitors increase osteoporosis risk. However, HMGCR inhibitors are unremarkably linked to osteoporosis.

Neuroprotective Effect and Mechanism of Tanreqing Injection on Ischemic Stroke: Insights from Network Pharmacology and in vivo Experiments.

OBJECTIVE: To explore the neuroprotective effects and mechanism of Tanreqing Injection (TRQ) on treating ischemic stroke based on network pharmacology and in vivo experimental validation. METHODS: The chemical compounds of TRQ were retrieved based on published data, with targets retrieved from PubChem, Therapeutic Target Database and DrugBank. Network visualization and analysis were performed using Cytoscape, with protein-protein interaction networks derived from the STRING database. Enrichment analysis was performed using Kyoto Encyclopedia of Genes Genomes pathway and Gene Ontology analysis. In in vivo experiments, the middle cerebral artery occlusion (MCAO) model was used. Infarct volume was determined by 2,3,5-triphenyltetrazolium hydrochloride staining and protein expressions were analyzed by Western blot. Molecular docking was performed to predict ligand-receptor interactions. RESULTS: We screened 81 chemical compounds in TRQ and retrieved their therapeutic targets. Of the targets, 116 were therapeutic targets for stroke. The enrichment analysis showed that the apelin signaling pathway was a key pathway for ischemic stroke. Furthermore, in in vivo experiment we found that administering with intraperitoneal injection of 2.5 mL/kg TRQ every 6 h could significantly reduce the infarct volume of MCAO rats (P<0.05). In addition, protein levels of the apelin receptor (APJ)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway were increased by TRQ (P<0.05). In addition, 41 chemical compounds in TRQ could bind to APJ. CONCLUSIONS: The neuroprotective effect of TRQ may be related to the APJ/PI3K/AKT signaling pathway. However, further studies are needed to confirm the findings.

Bio-accumulation and health risk assessments of per- and polyfluoroalkyl substances in wheat grains.

Per- and polyfluoroalkyl substances (PFASs) have been widely detected in various food, which has attracted worldwide concern. However, the factors influencing the transfer and bio-accumulation of PFASs from soils to wheat in normal farmland, is still ambiguous. We investigated the PFASs accumulation in agricultural soils and grains from 10 cites, China, and evaluated the health risks of PFASs via wheat consumption. Our results show that ∑PFASs in soils range from 0.34 µg/kg to 1.59 µg/kg with PFOA and PFOS dominating, whilst ∑PFASs in wheats range from 2.74 to 6.01 µg/kg with PFOA, PFBA and PFHxS dominating. The lower pH conditions and high total organic carbon (TOC) could result in the higher accumulation of PFASs in soils and subsequently in wheat grains, whilst the bioaccumulation factors of PFASs increase with increasing pH conditions but not with TOC. The estimated daily intake (EDI) values of PFBA, PFOA, and PFHxS are relatively high, but data supports that ingesting wheat grains does not result in any potential risk to the human beings. Our studies provided more information about PFASs accumulation in wheat grains, and help us understand the current potential risks of PFASs in food.

Engineering of Thermoelectric Composites Based on Silver Selenide in Aqueous Solution and Ambient Temperature.

The direct, solid state, and reversible conversion between heat and electricity using thermoelectric devices finds numerous potential uses, especially around room temperature. However, the relatively high material processing cost limits their real applications. Silver selenide (Ag2Se) is one of the very few n-type thermoelectric (TE) materials for room-temperature applications. Herein, we report a room temperature, fast, and aqueous-phase synthesis approach to produce Ag2Se, which can be extended to other metal chalcogenides. These materials reach TE figures of merit (zT) of up to 0.76 at 380 K. To improve these values, bismuth sulfide (Bi2S3) particles also prepared in an aqueous solution are incorporated into the Ag2Se matrix. In this way, a series of Ag2Se/Bi2S3 composites with Bi2S3 wt % of 0.5, 1.0, and 1.5 are prepared by solution blending and hot-press sintering. The presence of Bi2S3 significantly improves the Seebeck coefficient and power factor while at the same time decreasing the thermal conductivity with no apparent drop in electrical conductivity. Thus, a maximum zT value of 0.96 is achieved in the composites with 1.0 wt % Bi2S3 at 370 K. Furthermore, a high average zT value (zTave) of 0.93 in the 300-390 K range is demonstrated.

Two Decades of Publications in Journals Dedicated to Autoimmunity: A Bibliometric Analysis of the Autoimmunity Field from 2004 to 2023.

To carry out an in-depth analysis of the scientific research on autoimmunity, we performed the first bibliometric analysis focusing on publications in journals dedicated to autoimmunity (JDTA) indexed by science citation index during the period 2004-2023. Using bibliometric analysis, we quantitatively and qualitatively analyzed the country, institution, author, reference and keywords information of publications in JDTA, so as to understand the quantity, publication pattern and publication characteristics of these publications. The co-occurrence networks, clustering map and timeline map were created by CiteSpace and VOSviewer software to visualize the results. The CiteSpace was also used to analyze the strongest citation burst of keywords, which could describe the frequency, intensity and time period of high-frequency keywords, and indicate the research hotspots in the field. A total of 5 710 publications were analyzed, and their annual distribution number was basically stable from 2004 to 2023, fluctuating around 300. The United States and Italy led the way in terms of the number of publications, followed by France and China. For international cooperation, the developed countries represented by the United States cooperate more closely, but the cooperation was localized, reflecting that there was no unified model of autoimmunity among countries. UDICE-French Research Universities had the greatest number of publications. Subsequently, the number of publications decreased slowly with the ranking, and the gradient was not large. Eric Gershwin and Yehuda Shoenfeld stood out among the authors. They had an excellent academic reputation and great influence in the field of autoimmunity. The results of keyword analysis showed that JDTA publications mainly studied a variety of autoimmune diseases, especially SLE and RA. At the same time, JDTA publications also paid special attention to the research of cell function, autoantibody expression, animal experiments, disease activity, pathogenesis and treatment. This study is the first to analyze the publications in JDTA from multiple indicators by bibliometrics, thus providing new insights into the research hotspots and development trends in the field of autoimmunity.

Therapeutic potential of single-nucleotide polymorphism-mediated IL6R inhibitors in ankylosing spondylitis treatment.

Objective: Interleukin-6 (IL-6) is a multiple-effect cell factor implicated in the etiopathogenesis of several rheumatologic disorders. The blockade of the IL-6 pathway via IL6R inhibitors effectively treats these disorders. However, the clinical significance of the IL6R blockade for ankylosing spondylitis (AS) therapy remains controversial. With advances in genomics, increasing evidence has revealed the role of heritability in the etiology of disease, and Mendelian randomization (MR) analyses are being used more broadly to infer causation. Therefore, this MR study aims to evaluate the potential therapeutic utility of IL6R-targeted approaches in AS. Methods: The C-reactive protein (CRP) level was used as an exposure factor, and rheumatoid arthritis (RA) was used as a positive control. As-related genome-wide association study (GWAS) data were used as the primary outcome of drug-targeted MR analyses to test the relation between IL6R blockers and AS. Inverse variance weighting (IVW) is the primary analytical approach. Various sensitivity tests were performed to check the robustness and trustworthiness of the causality estimation, including consistency, heterogeneity, and pleiotropy analyses. In addition, repeated analysis was conducted using different GWAS data related to exposures and outcomes to examine the results for stability. Results: According to the IVW results, IL6R inhibitors significantly reduced the risk of AS in ukb-b-18194 (OR: 0.995, 95% CI 0.993-0.996, P = 5.12 × 10-08) and ukb-a-88 (OR: 0.994, 95% CI 0.993-0.996, P = 6.25 × 10-15). Moreover, repeated analyses were performed using different exposure-related GWAS data, yielding similar results, ukb-b-18194 (OR: 0.995, 95% CI 0.993-0.997, P = 1.25 × 10-06) and ukb-a-88 (OR: 0.995, 95% CI 0.994-0.997, P = 7.81 × 10-09). Heterogeneity analyses and pleiotropy analyses indicated no significant heterogeneity or pleiotropy. Conclusion: This MR analysis result further validates that the IL-6 pathway may contribute to the pathogenesis of AS and that the inhibition of IL6R reduces the risk of AS. These findings may guide future studies and provide more favorable drug treatment options for people at high risk of AS.

The urinary microbiota composition and functionality of calcium oxalate stone formers.

Background: Accumulated evidences indicate that dysbiosis of the urinary microbiota is associated with kidney stone formation. In the present study, we aimed to investigate the urinary microbiota composition and functionality of patients with calcium oxalate stones and compare it with those of healthy individuals. Method: We collected bladder urine samples from 68 adult patients with calcium oxalate stones and 54 age-matched healthy controls by transurethral catheterization. 16S rRNA gene and shotgun sequencing were utilized to characterize the urinary microbiota and functionality associated with calcium oxalate stones. Results: After further exclusion, a total of 100 subjects was finally included and analyzed. The diversity of the urinary microbiota in calcium oxalate stone patients was not significantly different from that of healthy controls. However, the urinary microbiota structure of calcium oxalate stone formers significantly differed from that of healthy controls (PERMANOVA, r = 0.026, P = 0.019). Differential representation of bacteria (e.g., Bifidobacterium) and several enriched functional pathways (e.g., threonine biosynthesis) were identified in the urine of calcium oxalate stone patients. Conclusion: Our results showed significantly different urinary microbiota structure and several enriched functional pathways in calcium oxalate stone patients, which provide new insight into the pathogenesis of calcium oxalate stones.