Melatonin enhances resistance to Botryosphaeria dothidea in pear by promoting jasmonic acid and phlorizin biosynthesis.

Ring rot, caused by Botryosphaeria dothidea, is an important fungal disease of pear fruit during postharvest storage. Melatonin, as a plant growth regulator, plays an important role in enhancing the stress resistance of pear fruits. It enhances the resistance of pear fruits to ring rot by enhancing their antioxidant capacity. However, the underlying mechanism remains unclear. In this study, we examined the effect of melatonin on the growth of B. dothidea. Results showed that melatonin did not limit the growth of B. dothidea during in vitro culture. However, metabolomics and transcriptomics analyses of 'Whangkeumbae' pear (Pyrus pyrifolia) revealed that melatonin increased the activity of antioxidant enzymes, including peroxidase (POD), superoxide dismutase (SOD), and polyphenol oxidase (PPO), in the fruit and activated the phenylpropanoid metabolic pathway to improve fruit resistance. Furthermore, melatonin treatment significantly increased the contents of jasmonic acid and phlorizin in pear fruit, both of which could improve disease resistance. Jasmonic acid regulates melatonin synthesis and can also promote phlorizin synthesis, ultimately improving the resistance of pear fruit to ring rot. In summary, the interaction between melatonin and jasmonic acid and phlorizin enhances the antioxidant defense response and phenylpropanoid metabolism pathway of pear fruit, thereby enhancing the resistance of pear fruit to ring rot disease. Our results provide new insights into the application of melatonin in the resistance to pear fruit ring rot.

Multienzyme-Like Nanozyme Encapsulated Ocular Microneedles for Keratitis Treatment.

Keratitis, an inflammation of the cornea caused by bacterial or fungal infections, is one of the leading causes of severe visual disability and blindness. Keratitis treatment requires both the prevention of infection and the reduction of inflammation. However, owing to their limited therapeutic functions, in addition to the ocular barrier, existing conventional medications are characterized by poor efficacy and low bioavailability, requiring high dosages or frequent topical treatment, which represents a burden on patients and increases the risk of side effects. In this study, manganese oxide nanocluster-decorated graphdiyne nanosheets (MnOx/GDY) are developed as multienzyme-like nanozymes for the treatment of infectious keratitis and loaded into hyaluronic acid and polymethyl methacrylate-based ocular microneedles (MGMN). MGMN not only exhibits antimicrobial and anti-inflammatory effects owing to its multienzyme-like activities, including oxidase, peroxidase, catalase, and superoxide dismutase mimics but also crosses the ocular barrier and shows increased bioavailability via the microneedle system. Moreover, MGMN is demonstrated to eliminate pathogens, prevent biofilm formation, reduce inflammation, alleviate ocular hypoxia, and promote the repair of corneal epithelial damage in in vitro, ex vivo, and in vivo experiments, thus providing a better therapeutic effect than commercial ophthalmic voriconazole, with no obvious microbial resistance or cytotoxicity.

Metagenome reveals the possible mechanism that microbial strains promote methanogenesis during anaerobic digestion of food waste.

For better understanding the mechanism of microbial strains promoting methane production, four strains Hungatella xylanolytica A5, Bacillus licheniformis B1, Paraclostridium benzoelyticum C2 and Advenella faeciporci E1 were inoculated into anaerobic digestion systems. After bioaugmentation, the cumulative methane production of A5, B1, C2 and E1 groups elevated by 11.68%, 8.20%, 18.21% and 15.67% compared to CK group, respectively. The metagenomic analysis revealed that the species diversity and uniformity of the experimental groups was improved, and hydrolytic acidifying bacteria, represented by Clostridiaceae, Anaerolineaceae and Oscillospiraceae, and methanogens, such as Methanotrichaceae and Methanobacteriaceae, were enriched. Meanwhile, the abundance of key genes in carbohydrate, pyruvate and methane metabolism was increased in the inoculated groups, providing reasonable reasons for more methane production. The strengthening mechanism of microbial strains in this study offered a theoretical foundation for selecting a suitable bioaugmentation strategy to solve the problems of slow start-up and low methane production in anaerobic digestion.

Evaluating the potential of different bioaugmented strains to enhance methane production during thermophilic anaerobic digestion of food waste.

Bioaugmentation technology for improving the performance of thermophilic anaerobic digestion (TAD) of food waste (FW) treatment is gaining more attention. In this study, four thermophilic strains (Ureibacillus suwonensis E11, Clostridium thermopalmarium HK1, Bacillus thermoamylovorans Y25 and Caldibacillus thermoamylovorans QK5) were inoculated in the TAD of FW system, and the biochemical methane potential (BMP) batch study was conducted to assess the potential of different bioaugmented strains to enhance methane production. The results showed that the cumulative methane production in groups inoculated with E11, HK1, Y25 and QK5 improved by 2.05%, 14.54%, 19.79% and 9.17%, respectively, compared with the control group with no inoculation. Moreover, microbial community composition analysis indicated that the relative abundance of the main hydrolytic bacteria and/or methanogenic archaea was increased after bioaugmentation, and the four strains successfully became representative bacterial biomarkers in each group. The four strains enhanced methane production by strengthening starch, sucrose, galactose, pyruvate and methane metabolism functions. Further, the correlation networks demonstrated that the representative bacterial genera had positive correlations with the differential metabolic functions in each bioaugmentation group. This study provides new insights into the TAD of FW with bioaugmented strains.

Global patterns of asthma burden related to environmental risk factors during 1990-2019: an age-period-cohort analysis for global burden of disease study 2019.

BACKGROUND: Change in asthma burden attributed to specific environmental risk factor has not been evaluated. OBJECTIVE: We aimed to explore the age, period, and cohort effects on asthma burden attributable to smoking and occupational asthmagens in different socio-demographic index (SDI) regions and the region and sex disparities. METHODS: Risk factor-specific asthma deaths and disability-adjusted life years (DALYs) rates were extracted from Global Burden of Disease study 2019, estimated by standard Combined Cause of Death Model and DisMod-MR 2.1 modeling tool. Age-period-cohort analysis was conducted to decompose age, period, and cohort effects on asthma burden. RESULTS: Smoking- and occupational asthmagens-related asthma deaths and DALYs rates dropped by > 45% during 1990-2019. In 2019, Africa, South and Southeast Asia had higher asthma burden than other regions. Male had higher asthma burden than female. Among nearly all age groups, low-middle SDI region had the highest smoking-related asthma burden, and low SDI region had the highest occupational asthmagens-related asthma burden. Inverse "V" shaped trend was observed in the above regions with increasing age. For smoking-related asthma deaths and DALYs rates, the most significant improvement of period rate ratio (RR) occurred in high SDI region, decreased from 1.67 (1.61, 1.74) to 0.34 (0.33, 0.36) and 1.61 (1.57, 1.66) to 0.59 (0.57, 0.61), respectively, as well as the cohort effect on smoking-related asthma burden. For occupational asthmagens-related asthma deaths and DALYs rates, the most sharply decrease of period and cohort RR appeared in the high and high-middle SDI regions. Low SDI region showed least progress in period and cohort RR of smoking- and occupational asthmagens-linked asthma burden. CONCLUSION: Smoking- and occupational asthmagens-related asthma burden sharply decreases, but region and sex disparities exist. Policy makers from low SDI region should reinforce tobacco control and prioritize workplace protection.

Trend and heterogeneity in forced vital capacity among Chinese students during 1985-2019: results from Chinese National Survey on Students' Constitution and Health.

BACKGROUND: Forced vital capacity (FVC) reflects respiratory health, but the long-term trend and heterogeneity in FVC of Chinese students were understudied. METHODS: Data were from Chinese National Survey on Students' Constitution and Health 1985-2019. Super Imposition by Translation and Rotation model was used to draw FVC growth curves. Sex-, region-, and nationality-heterogeneity in FVC was evaluated. Spearman correlation and generalized additive model was used to reveal influencing factors for FVC. RESULTS: Compared to 1985, age at peak FVC velocity was 1.09, 3.17, 0.74, and 1.87 years earlier for urban male, urban female, rural male, and rural female in 2019, respectively. Peak FVC velocity first decreased and then increased during 1985-2019, only male rebounded to larger than 1985 level. FVC declined from 1985 to 2005 and then raised. Males consistently had higher FVC than females, with disparities increasing in the 13-15 age group. Urban students also had higher FVC than rural students. In 2019, FVC difference between 30 Chinese provinces and the national average showed four scenarios: consistently above national average; less than national average until age 18, then above; greater than national average until age 18, then this advantage reversed; less than national average in almost all the age. Most Chinese ethnic minority students had lower FVC levels compared to Han students. Spearman correlation and generalized additive model showed that age, sex, and height were the leading influencing factors of FVC, followed by socioeconomic and environmental factors. CONCLUSIONS: Chinese students experienced advanced FVC spurt, and there was sex-, region- and nationality-heterogeneity in FVC. Routine measurement of FVC is necessary in less developed areas of China.

Essential Involvement of Neutrophil Elastase in Acute Acetaminophen Hepatotoxicity Using BALB/c Mice.

Intense neutrophil infiltration into the liver is a characteristic of acetaminophen-induced acute liver injury. Neutrophil elastase is released by neutrophils during inflammation. To elucidate the involvement of neutrophil elastase in acetaminophen-induced liver injury, we investigated the efficacy of a potent and specific neutrophil elastase inhibitor, sivelestat, in mice with acetaminophen-induced acute liver injury. Intraperitoneal administration of 750 mg/kg of acetaminophen caused severe liver damage, such as elevated serum transaminase levels, centrilobular hepatic necrosis, and neutrophil infiltration, with approximately 50% mortality in BALB/c mice within 48 h of administration. However, in mice treated with sivelestat 30 min after the acetaminophen challenge, all mice survived, with reduced serum transaminase elevation and diminished hepatic necrosis. In addition, mice treated with sivelestat had reduced NOS-II expression and hepatic neutrophil infiltration after the acetaminophen challenge. Furthermore, treatment with sivelestat at 3 h after the acetaminophen challenge significantly improved survival. These findings indicate a new clinical application for sivelestat in the treatment of acetaminophen-induced liver failure through mechanisms involving the regulation of neutrophil migration and NO production.

Starvation Affects the Muscular Morphology, Antioxidant Enzyme Activity, Expression of Lipid Metabolism-Related Genes, and Transcriptomic Profile of Javelin Goby (Synechogobius hasta).

Fish in natural and cultivated environments can be challenged by starvation. However, inducing starvation in a controlled manner cannot only reduce feed consumption but also reduces aquatic eutrophication and even improves farmed fish quality. This study investigated the effects of starvation on the muscular function, morphology, and regulatory signaling in javelin goby (Synechogobius hasta) by evaluating the biochemical, histological, antioxidant, and transcriptional changes in the musculature of S. hasta subjected to 3, 7, and 14 days fasting. The muscle glycogen and triglyceride levels in S. hasta were gradually reduced under starvation, reaching their lowest at the end of the trial (P < 0.05). The levels of glutathione and superoxide dismutase were significantly elevated after 3-7 days of starvation (P < 0.05), but later returned to the level of the control group. The muscle of starved S. hasta developed structural abnormalities in some areas after 7 days of food deprivation, and more vacuolation and more atrophic myofibers were observed in 14-day fasted fish. The transcript levels of stearoyl-CoA desaturase 1 (scd1), the key gene involved in the biosynthesis of monounsaturated fatty acids, were markedly lower in the groups starved for 7 or more days (P < 0.05). However, the relative expressions of genes associated with lipolysis were decreased in the fasting experiment (P < 0.05). Similar declines in the transcriptional response to starvation were found in muscle fatp1 and ppar γ abundance (P < 0.05). Furthermore, the de novo transcriptome of muscle tissue from the control, 3-day and 14-day starved S. hasta generated 79,255 unigenes. The numbers of differentially expressed genes (DEGs) identified by pairwise comparisons among three groups were 3276, 7354, and 542, respectively. The enrichment analysis revealed that the DEGs were primarily involved in metabolism-related pathways, including ribosome, TCA pathway, and pyruvate metabolism. Moreover, the qRT-PCR results of 12 DEGs validated the expression trends observed in the RNA-seq data. Taken together, these findings demonstrated the specific phenotypical and molecular responses of muscular function and morphology in starved S. hasta, which may offer preliminary reference data for optimizing operational strategies incorporating fasting/refeeding cycles in aquaculture.

Rhodium(III)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols.

An efficient Rh(iii)-catalyzed C-H oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols by merging tandem C-H and C-C cleavage was developed. This transformation features mild reaction conditions, high regioselectivity, and excellent functional group compatibility. The resulting ß-aryl ketone derivatives can be readily transformed into 7-azaindole-containing π-extended polycyclic heteroarenes.

Correction: Rhodium(iii)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols.

Correction for 'Rhodium(iii)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols' by Jidan Liu et al., Org. Biomol. Chem., 2021, DOI: .

Removal of antibiotic resistance genes from swine wastewater by membrane filtration treatment.

Antibiotic resistance genes (ARGs) have attracted extensive attention as an emerging environmental contaminant potentially threatening humans. One of the main emission sources of ARGs is swine wastewater. In this study, integrated membrane filtration including ultrafiltration and two-stage reverse osmosis was conducted for swine wastewater treatment. The abundances of 16 target ARGs, which accounted for 72.64% of the total ARGs in swine wastewater according to metagenomic sequencing, were quantified by quantitative real-time PCR (qPCR) during each stage of the membrane filtration process. The results showed that integrated membrane filtration could reduce more than 99.0% of conventional pollutants and 99.79% of ARGs (from 3.02 × 108 copy numbers/mL to 6.45 × 105 copy numbers/mL). Principal component analysis (PCA) indicated that the removal efficiency of ARGs subtype by membrane filtration did not depend on ARGs type. However, strong correlations were found between ARGs and the wastewater quality indicators TP, SS and EC according to Cooccurrence patterns, indicating that ARG removal was closely associated with insoluble solid particles and soluble ions in swine wastewater. These results showed that membrane filtration could not only remove conventional pollutants such as nitrogen and phosphorus but also reduce the emerging pollutant of ARGs and decrease the risk of ARGs flowing into natural water.

Squamous cell carcinoma transformation in mature cystic teratoma of the ovary: a systematic review.

BACKGROUND: 0.17-2% of mature cystic teratoma of the ovary (MCTO) undergo malignant transformation, of which 80% are squamous cell carcinoma (SCC) transformation in MCTO. We aim to investigate the clinical characteristics and treatment of SCC transformation in MCTO METHODS: We systematically searched PubMed database and individual patient data about SCC transformation in MCTO were extracted. The published cases were combined with 6 cases of SCC transformation in MCTO from Qilu Hospital, Shandong University. RESULTS: The incidence of SCC transformation in MCTO was 0.3%. A total of 435 cases of SCC transformation in MCTO were enrolled in the analysis. The mean age of diagnosis was 53.5 (range 19-87) years old. The most common clinical manifestations were abdominal pain (47.3%) and abdominal mass (26.0%). StageI,II, III and IV accounted for 50.0, 18.8, 26.8 and 4.4% of all cases, respectively. Patients with stage I had significantly better prognosis than stage II, III and IV patients (P < 0.01). Hysterectomy can improve overall survival (P < 0.01). For patients younger than 45 years old with stageIA orIC, there was no difference in mortality between fertility-sparing and radical surgery (P = 1.00). Adjuvant chemotherapy can improve survival in patients with advanced stage (P = 0.02), and chemotherapy with platinum was related to better prognosis (P = 0.02). CONCLUSION: SCC transformation in MCTO is a rare malignancy mainly occurs in older age. FIGO stage is an independent prognostic factor. Hysterectomy and platinum-based chemotherapy are associated with better survival. Fertility-sparing surgery is feasible for young patients with early stage.

[Research progress of CT/MRI parametric response map in precision evaluation of therapeutic response of cancer patients].

Intratumor spatial heterogeneity has been ignored in evaluating tumor therapeutic effect with conventional imaging methods. The voxel-based parametric response map (PRM) derived from CT or MRI may accurately, objectively and timely evaluate the tumor response to therapy, by comparing changes of the functional parameters before and after treatment. This approach may improve the imaging monitoring and the sensitivity of spatial resolution related to tumor changes after treatment. Thus, PRM may help to improve the treatment plan and prognosis evaluation for patients. This article reviews progress on CT/MRI PRM in precision evaluation of therapeutic response of cancer patients.

[Rat endothelial progenitor cells labeled with Molday IONTM EverGreen and in vitro MRI study].

OBJECTIVE: To investigate the feasibility of labeling endothelial progenitor cells (EPCs) with a novel dual modal contrast agent Molday IONTM EverGreen(MIEG) and its performance in vitro MRI. METHODS: EPCs were isolated from rat bone marrow and labeled with 10, 20, 50 µg/mL MIEG, respectively. The labeling rates were identified by Prussian blue staining and fluorescence microscopy. The vitality of EPCs labeled with 20 µg/mL MIEG was detected by trypan blue exclusion test at 1 d, 1 w, 2 w, and 6 w after labeling. EPCs labeled with different concentrations of MIEG were scanned by 3.0T MRI with T1 weighted and T2 weighted imaging. RESULTS: The labeling rates for EPCs labeled with different concentrations of MIEG were greater than 98%,and the cytoplasm of labeled EPCs was present with Prussian blue staining. Although the green lighting level went down, the labeling rate at 6 w after labeling was greater than 90%. Trypan blue exclusion test showed that there was no significant difference in the vitality between EPCs labeled with MIEG at 1 d, 1 w, 2 w and 6 w after labeling and EPCs without labeling (all P>0.05). There was no difference in signal intensity on T1 weighted image among EPCs labeled with different concentrations of MIEG. However, the signal intensity on T2 weighted image was reduced in all labeled groups, and the signal reduction became more apparent with increased concentration of MIEG. CONCLUSIONS: EPCs can be effectively labeled by MIEG without interference on the cell viability at the labeled concentration of 20 µg/mL. The signal intensity change of labeled cells can be detected sensitively by T2 weighted imaging at 3.0T MRI.

[Clinical features of inhaled and blood-borne Staphylococcus aureus pneumonia and analysis of antibiotic resistance of the pathogen in children].

OBJECTIVE: To compare the clinical manifestations between inhaled and blood-borne Staphylococcus aureus pneumonia (SAP) and the antibiotic resistance between the isolates of inhaled and blood-borne Staphylococcus aureus. METHODS: The clinical data of 44 pediatric SAP cases in the Children′s Hospital, Chongqing Medical University from January 2008 to December 2013 were retrospectively analyzed. Twenty-four cases were identified as inhaled SAP, and 20 cases as blood-borne SAP. RESULTS: Inhaled SAP was more common in children younger than 3 years of age, while blood-borne SAP was more prevalent in children older than 6 years of age. Patients with inhaled SAP had significantly higher incidence rates of cough, wheeze, moist rales, dyspnea and empyema than those with blood-borne SAP (P<0.05). The patients with blood-borne SAP were more vulnerable to severe fever, unconsciousness, dysfunction of liver and kidney, pyogenic osteomyelitis, septic arthritis, sepsis, and abscess of skin and soft tissues (P<0.05). Inhaled SAP isolates had significantly higher rates of resistance to amoxicillin/clavulanic acid, oxacillin, and cefoxitin than blood-borne SAP isolates (P<0.05), while the latter had a higher rate of resistance to cotrimoxazole (P<0.05). CONCLUSIONS: Inhaled SAP often occurs in children younger than 3 years of age, and the respiratory manifestations are commonly seen. Blood-borne SAP often occurs in children older than 6 years of age, with the infectious-toxic symptoms that result in multiple organ infection and dysfunction. The isolates of inhaled and blood-borne SAP have different antibiograms.

[Analysis of serum vancomycin concentration after administration of different doses in children with Staphylococcus aureus pneumonia].

OBJECTIVE: To analyze serum vancomycin concentration after administration of different therapeutic doses in children with Staphylococcus aureus pneumonia (SAP) in order to determine the appropriate dose of vancomycin in clinical administration. METHODS: The clinical data of 35 children who were diagnosed with SAP and treated with vancomycin from January 2008 to December 2013 were retrospectively analyzed. RESULTS: Among the 35 SAP cases with vancomycin therapy, 22 cases (63%) had serum vancomycin trough concentration monitored. The numbers of cases with vancomycin at 10, 12.5, and 15 mg/(kg·dose) × every 6 hours (q6h) were 11, 4 and 7, respectively. The mean serum trough concentration of vancomycin in the 15 mg/(kg·dose) group was 14.98 mg/L, which was significantly higher than in the 10 mg/(kg·dose) and 12.5 mg/(kg·dose) groups (4.97 and 8.00 mg/L respectively; P<0.05). The percentage of cases that reached the expected trough concentration in the 15 mg/(kg·dose) group (71%) was significantly higher than that in the 10 mg/(kg·dose) group (9%), but there was no significant difference in this percentage between the 15 mg/(kg·dose) and 12.5 mg/(kg·dose) groups (71% vs 25%). CONCLUSIONS: The reasonable dosage of vancomycin for the treatment of pediatric SAP is 15 mg/(kg·dose) × q6h or 60 mg/(kg·d).

Single-atom nanozymes for antibacterial applications.

Bacteria have always been a thorny problem that threatens human health and food safety. Conventional antibiotic treatment often leads to the emergence of drug resistance. Therefore, the development of more effective antibacterial agents is urgently needed. Single-atom nanozymes (SAzymes) can efficiently eliminate bacteria due to their high atomic utilization, abundant active centers, and good natural enzyme mimicry, providing a potential alternative choice for antibiotics in antibacterial applications. Here, the antibacterial applications of SAzymes are reviewed and their catalytic properties are discussed from the aspects of active sites, coordination environment regulation and carrier selection. Then, the antibacterial effect of SAzymes is elaborated in combination with photothermal therapy (PTT) and sonodynamic therapy (SDT). Finally, the problems faced by SAzymes in antibacterial applications and their future development potential are proposed.

Sleep Duration and Risk of Periodontitis-A Systematic Review and Meta-Analysis.

Periodontitis, with a high prevalence in the whole population, is the main cause of tooth loss. Some studies have revealed that sleep duration may be related to periodontitis, however, the opinions are not consistent. This meta-analysis was carried out to study the potential relationship between sleep duration and periodontitis. A search of relevant articles was conducted on Embase, PubMed, Cochrane Library, and Web of Science. Papers published until the end of November 2022 reporting associations between sleep duration and periodontitis were considered. The pooled odds ratio (OR) with a 95% confidence interval (CI) was calculated to assess the association. Software STATA 14.0 was employed to conduct this analysis. A total of 11 cross-sectional studies were included. Our study showed neither short sleep duration (SSD) nor long sleep duration (LSD) were associated with periodontitis (SSD: OR = 1.04, 95% CI: 0.83, 1.29; LSD: OR = 1.12, 95% CI: 0.94, 1.23), while higher prevalence was observed when sleep duration ≤5 h (OR = 1.41, 95% CI: 1.33, 1.51). In addition, both SSD and LSD were not associated with severe periodontitis (SSD: OR = 0.94, 95% CI: 0.75, 1.16; LSD: OR = 1.19, 95% CI: 0.80, 1.76). In conclusion, the present review indicated that too little sleep duration (≤5 h) significantly increased the risk of periodontitis. However, the evidence is limited due to cross-sectional design of most studies, Hence longitudinal studies should be conducted to support this finding.

The complete chloroplast genome of Saccharum fulvum (Poaceae).

Saccharum species are of great importance as fruit crops due to their economic and food value. S. fulvum is a wild relative of sugarcane that has a wide geographic distribution and is well-adapted to various environmental conditions. It exhibits high resistance to pests, diseases, drought, cold, and degraded soils, making it a valuable resource for sugarcane research. Here, we report the chloroplast genome of S. fulvum. This chloroplast genome was 141,151 bp in length with a GC content of 38.41%. The large single-copy, small single-copy, and inverted repeat regions were 83,030 bp, 12,533 bp, and 22,794 bp in length, respectively. The chloroplast genome contained 111 different genes, including 77 protein-coding genes, 4 rRNA genes, and 30 tRNA genes. Phylogenetic analysis indicated that S. fulvum was closely related to S. narenga. This study not only enriches the genome information of Saccharum, but also will be useful for the evolutionary study of the family Poaceae.

Advances and challenges in the electrochemical reduction of carbon dioxide.

The electrocatalytic carbon dioxide reduction reaction (ECO2RR) is a promising way to realize the transformation of waste into valuable material, which can not only meet the environmental goal of reducing carbon emissions, but also obtain clean energy and valuable industrial products simultaneously. Herein, we first introduce the complex CO2RR mechanisms based on the number of carbons in the product. Since the coupling of C-C bonds is unanimously recognized as the key mechanism step in the ECO2RR for the generation of high-value products, the structural-activity relationship of electrocatalysts is systematically reviewed. Next, we comprehensively classify the latest developments, both experimental and theoretical, in different categories of cutting-edge electrocatalysts and provide theoretical insights on various aspects. Finally, challenges are discussed from the perspectives of both materials and devices to inspire researchers to promote the industrial application of the ECO2RR at the earliest.