ObjectiveThe exacerbating trend of global population aging poses profound socioeconomic and public health challenges, making the comprehensive elucidation of biological aging mechanisms and the discovery of effective anti-aging interventions an urgent priority in the life sciences. Based on our previous serum metabolomics findings that dimethylglycine, an intermediate metabolite of amino acid metabolism naturally present in the human body, was significantly enriched in the serum of longevity families, this study aimed to systematically investigate the anti-aging effects of dimethylglycine both in living organisms and in controlled laboratory environments, and to preliminarily elucidate its underlying molecular mechanisms. While existing literature indicates that dimethylglycine possesses antioxidant and immunomodulatory properties, its direct anti-aging efficacy and the specific molecular pathways through which it operates remain largely unexplored. MethodsTo comprehensively evaluate the anti-aging properties of dimethylglycine, we utilized replicative senescent human embryonic lung fibroblasts, specifically the WI-38 cell line, as an experimental model in a controlled laboratory environment. Cell viability and safety were thoroughly assessed using Cell Counting Kit-8 and lactate dehydrogenase release assays across various concentrations of dimethylglycine. The impact of dimethylglycine on cellular senescence phenotypes, oxidative stress, and proliferative capacity was evaluated via senescence-associated beta-galactosidase staining, reactive oxygen species fluorescence detection, and 5-ethynyl-2'-deoxyuridine incorporation assays. Furthermore, the molecular alterations of senescence-associated secretory phenotype factors and core senescence signaling pathways were quantified using quantitative reverse transcription polymerase chain reaction for the messenger RNA levels of interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1, and enzyme-linked immunosorbent assay for the measurement of p16 and p21 protein expression levels. For the living organism model, the wild-type nematode Caenorhabditis elegans was used to evaluate systemic physiological effects. We conducted a comprehensive lifespan analysis at 20°C, heat stress resistance survival assays at 35℃, senescence-associated beta-galactosidase staining, lipofuscin accumulation tracking, intracellular reactive oxygen species measurement, and Oil Red O staining to ascertain systemic lipid accumulation. Additionally, network pharmacology bioinformatics tools, including PharmMapper and STRING databases, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were utilized to predict target pathways, alongside highly detailed molecular docking simulations utilizing SwissDock and Protein-Ligand Interaction Profiler to examine interactions with the cytochrome P450 family 2 subfamily C member 9 protein. ResultsThe experimental outcomes robustly demonstrate the potent anti-aging capabilities of dimethylglycine. At the cellular level, toxicity analyses firmly confirmed that dimethylglycine is highly safe; continuous treatment with 50 mol/L and 70 mol/L of dimethylglycine for 5 d did not induce any cellular membrane damage or cytotoxicity, but rather actively promoted cellular proliferation. Utilizing the optimal standardized concentration of 50 mol/L, dimethylglycine treatment significantly ameliorated senescent phenotypic markers in human embryonic lung fibroblasts, which was evidenced by a drastic and highly significant reduction in the senescence-associated beta-galactosidase positive cell percentage (P<0.000 1) and intracellular reactive oxygen species levels (P<0.000 1), alongside a marked increase in the 5-ethynyl-2'-deoxyuridine-positive proliferation rate (P=0.003 5). On a molecular expression scale, dimethylglycine significantly downregulated the messenger RNA expression of multiple core senescence-associated secretory phenotype inflammatory factors, including interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1. Concurrently, it effectively suppressed the protein expression of critical cell cycle arrest markers, diminishing p16 protein levels by 57.3% (P=0.000 4) and p21 protein levels by 27.2% (P=0.000 7). In the nematode Caenorhabditis elegans animal model, dimethylglycine significantly extended the mean lifespan from 20.402 d to an impressive 23.066 d (P<0.000 1) and notably enhanced overall survival rates under severe heat stress environmental conditions (P=0.017). Furthermore, systemic dimethylglycine intervention significantly mitigated age-related physiological decline by decreasing bodily lipofuscin accumulation (P<0.000 1), significantly reducing senescence-associated beta-galactosidase activity, lowering systemic reactive oxygen species fluorescence (P=0.008), and effectively alleviating overall fat accumulation (P<0.000 1). Mechanistically, extensive network pharmacology and Kyoto Encyclopedia of Genes and Genomes analyses strongly revealed that the potential targets of dimethylglycine are significantly enriched in fundamental drug metabolism and oxidative stress response pathways. Precision molecular docking simulations conclusively demonstrated that dimethylglycine forms highly stable structural interactions with the cytochrome P450 family 2 subfamily C member 9 protein, specifically highlighting the definitive formation of 5 stable hydrogen bonds involving serine 365, leucine 366, and serine 429 residues, as well as two critical salt bridge formations with arginine 97 and histidine 368 residues. It is additionally predicted to interact favorably with glutathione S-transferase family proteins. ConclusionDimethylglycine exhibits a profoundly significant and multifaceted anti-aging activity at both the cellular and entire living animal levels. By powerfully alleviating oxidative stress, heavily suppressing the core p16 and p21-dependent cellular senescence signaling pathways, and substantially mitigating the detrimental senescence-associated secretory phenotype, dimethylglycine effectively delays fundamental cellular senescence processes and drastically extends whole-organism lifespan. The biological mechanisms driving these robust protective effects are highly likely closely associated with its direct stable interactions with crucial metabolic and detoxifying enzyme systems, such as cytochrome P450 family 2 subfamily C member 9 and glutathione S-transferase family proteins, thereby systemically improving metabolic dysregulation and restoring critical redox homeostasis. This comprehensive study provides highly solid experimental evidence supporting dimethylglycine as a highly potent and safe potential anti-aging intervention agent, while simultaneously offering a clear molecular mechanistic explanation for the previously documented high abundance of dimethylglycine observed within exceptionally long-lived human populations.

ObjectiveTo investigate whether the effect of Danggui Shaoyaosan （DSS） on cognitive impairment is related to its promotion of ketone body metabolism in the brain and regulation of glutamate/α-amino-3-hydroxy-5-methyl-4-isox-azolepropionic acid receptor （AMPAR） pathway. MethodsMale APP/PS1 mice were randomized into model， low-dose （3.2 g·kg^-1） DSS， medium-dose （6.4 g·kg^-1） DSS， high-dose （12.8 g·kg^-1） DSS， ketogenic diet， and inhibitor （talampanel， 5 mg·kg^-1） groups. C57BL/6J wild-type mice were selected as the normal group. The talampanel group was intragastrically administered for 2 consecutive weeks from the 6th week， and the other groups were continuously treated for 8 weeks before behavioral testing. The ultrastructure of synapses in hippocampal CA1 region was observed by transmission electron microscopy， and calcium/calmodulin-dependent kinase Ⅱ （CaMKⅡ） expression was detected by immunohistochemistry （IHC）. The levels of β-hydroxybutyrate （BHB） and lactic acid （LAC） were measured by biochemical kits， and those of glutamate （Glu）， glutamine （Gln）， γ-aminobutyric acid （GABA）， and synaptophysin （SYP） by enzyme-linked immunosorbent assay （ELISA）. The mRNA levels of glutamine synthetase （GS）， glutaminase （GLS）， glutamate decarboxylase （GAD）， CaMKⅡ， and AMPAR subunits GluA1 and GluA2 were quantified by Real-time quantitative polymerase chain reaction （Real-time PCR）， and the protein levels of GS， GLS， GAD， GluA1， and GluA2 by Western blot. ResultsCompared with the normal group， the model group exhibited decreased recognition index， spontaneous alternation rate， and residence time in the target quadrant （P<0.01）， increased escape latency and ratio of the time in the opposite side of the target quadrant to the time in the target quadrant （P<0.05， P<0.01）， damaged synaptic ultrastructure of hippocampal CA1 region， increased positive expression of CaMKⅡ， no significant difference in BHB level， elevated LAC and Glu levels （P<0.01）， declined SYP， Gln， and GABA levels （P<0.01）， downregulated mRNA and protein levels of GS， GAD， and GluA2 （P<0.05， P<0.01）， and upregulated mRNA and protein levels of GLS and GluA1 （P<0.05， P<0.01） and mRNA level of CaMKⅡ （P<0.01）. Compared with the model group， DSS intervention improved the behavioral indexes of mice （P<0.05， P<0.01）， enhanced the synaptic ultrastructure plasticity in hippocampal CA1 region， decreased the positive expression of CaMKⅡ， raised the BHB level （P<0.01）， reduced the LAC and Glu levels （P<0.01）， elevated the SYP， Gln， and GABA levels （P<0.01）， upregulated the mRNA and protein levels of GS， GAD， and GluA2， and downregulated the mRNA and protein levels of GLS and GluA1 （P<0.05， P<0.01） and the mRNA level of CaMKⅡ （P<0.01）. ConclusionDSS can improve the learning and memory and enhance the synaptic plasticity of APP/PS1 mice. Its neuroprotective effect is coupled with the promotion of ketone body formation and remodeling of brain energy metabolism， and is related to the regulation of glutamate/AMPAR pathway.

Oral solid dosage forms require processes such as disintegration and dissolution to release the drug before it can be absorbed and utilized by the body. In this manuscript, imaging technology was used to continuously visualize and characterize the in vitro static drug release process of gliclazide modified release tablets from 15 manufacturers, combined with the traditional method of in vitro dissolution testing, to determine the release profile of gliclazide modified release tablets, to evaluate the similarity of the release profiles by using the similarity factor (f₂) method and based on the analysis of the release profiles fitted with a variety of mathematical models. The results indicate that the gliclazide modified release tablets produced by 14 companies are hydrophilic gel matrix tablets. Compared to the reference listed drug, the release profiles of formulations from 11 companies show high similarity (f₂ > 50) to the reference. Among these, formulations with visual characteristics similar to the reference exhibit similar release curves. This study provides an alternative method for the in vitro consistency evaluation of gliclazide modified release tablets, aiming to assess the in vitro release behaviour of generic formulations more accurately and comprehensively.

Adipose tissue is a critical energy reservoir in animals and humans, with multifaceted roles in endocrine regulation, immune response, and providing mechanical protection. Based on anatomical location and functional characteristics, adipose tissue can be categorized into distinct types, including white adipose tissue (WAT), brown adipose tissue (BAT), beige adipose tissue, and pink adipose tissue. Traditionally, adipose tissue research has centered on its morphological and functional properties as a whole. However, with the advent of single-cell transcriptomics, a new level of complexity in adipose tissue has been unveiled, showing that even under identical conditions, cells of the same type may exhibit significant variation in morphology, structure, function, and gene expression——phenomena collectively referred to as cellular heterogeneity. Single-cell transcriptomics, including techniques like single-cell RNA sequencing (scRNA-seq) and single-nucleus RNA sequencing (snRNA-seq), enables in-depth analysis of the diversity and heterogeneity of adipocytes at the single-cell level. This high-resolution approach has not only deepened our understanding of adipocyte functionality but also facilitated the discovery of previously unidentified cell types and gene expression patterns that may play key roles in adipose tissue function. This review delves into the latest advances in the application of single-cell transcriptomics in elucidating the heterogeneity and diversity within adipose tissue, highlighting how these findings have redefined the understanding of cell subpopulations within different adipose depots. Moreover, the review explores how single-cell transcriptomic technologies have enabled the study of cellular communication pathways and differentiation trajectories among adipose cell subgroups. By mapping these interactions and differentiation processes, researchers gain insights into how distinct cellular subpopulations coordinate within adipose tissues, which is crucial for maintaining tissue homeostasis and function. Understanding these mechanisms is essential, as dysregulation in adipose cell interactions and differentiation underlies a range of metabolic disorders, including obesity and diabetes mellitus type 2. Furthermore, single-cell transcriptomics holds promising implications for identifying therapeutic targets; by pinpointing specific cell types and gene pathways involved in adipose tissue dysfunction, these technologies pave the way for developing targeted interventions aimed at modulating specific adipose subpopulations. In summary, this review provides a comprehensive analysis of the role of single-cell transcriptomic technologies in uncovering the heterogeneity and functional diversity of adipose tissues.

ObjectiveBy comparing the composition and content of volatile components in raw products， wine-washed products and wine-fried products of Ligusticum sinense cv. Chaxiong rhizome（LSCR）， to investigate the influence of wine processing on the volatile components of LSCR， in order to provide a basis for the development of quality standards for LSCR and its processed products. MethodsElectronic nose was used to identify the odors of LSCR， wine-washed and wine-fried LSCR， and their volatile components were detected by headspace gas chromatography-mass spectrometry（HS-GC-MS）， and the relative mass fractions of these components were determined by peak area normalization method. Principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA） were performed on the obtained sample data by SIMCA 14.1 software， and the differential components of LSCR， wine-washed and wine-fried LSCR were screened according to the variable importance in the projection（VIP） value>1. Pearson correlation analysis was used to explore the relationship between volatile differential flavor components and electronic nose sensors. ResultsElectronic nose detection results showed that there were significant differences in the odors of LSCR， wine-washed and wine-fried LSCR， mainly reflected in the sensors S2， S4， S5， S6， S11， S12， S13. And a total of 62 compounds were identified from LSCR and its wine-processed products， among which 46， 50 and 51 compounds were identified from LSCR， wine-fried and wine-washed LSCR， respectively. There were 21 differential components between the raw products and wine-fried products， of which 10 components were increased and 11 were decreased after processing. There were 20 differential components between the raw products and wine-washed products， of which 11 constituents increased and 9 decreased after processing. There were 17 differential components between the wine-wash products and wine-fried products. Compared with the wine-washed products， the contents of 13 components in the wine-fried products increased， and the contents of 4 components decreased. The increasing trend of the content of phthalides in the wine-washed products was more obvious than that in the wine-fried products， but the content of total volatile components was higher in the wine-fried products than the wine-washed products. Correlation analysis showed that there were different degrees of correlation between the 7 differential sensors of electronic nose and 24 differential volatile components， mainly phthalides and olefins. ConclusionThe odor and the content of volatile components in LSCR changed obviously after wine processing， and n-butylphthalide， Z-butylidenephthalide and E-ligustilide can be used as the candidate differential markers of volatile components in LSCR before and after wine processing.

ObjectiveTo analyze the differences in color， odor and volatile components of Citri Reticulatae Pericarpium（CRP） before and after being stir-fried with Halloysitum Rubrum， and to explore the material basis of enhancing the effect of strengthening spleen after processing and the scientific connotation of decoction pieces processed with Halloysitum Rubrum as the auxiliary material. MethodsThe volatile components of the samples before and after processing were identified and relatively quantified by headspace gas chromatography-mass spectrometry（HS-GC-MS）， and the volatile components were analyzed by principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA）. According to the principle of variable importance in the projection（VIP） value>1.5， volatile differential components before and after processing were screened. And combined with intelligent sensory technologies such as colorimeter and electronic nose， the chroma and odor information of CRP before and after being stir-fried with Halloysitum Rubrum were identified. Pearson correlation analysis was used to explore the correlation between volatile differential components and chroma values. ResultsA total of 112 volatile components were identified from CRP and CRP stir-fried with Halloysitum Rubrum， of which 84 were from CRP and 97 were from CRP stir-fried with Halloysitum Rubrum. And 7 differential components were selected， including α-pinene， β-myrcene， linalool， sabinene， ocimene isomer mixture， A-ocimene， and δ-elemene. After being processed with Halloysitum Rubrum， the brightness value（L^*）， yellow-blue value（b^*） and total chromatic value（E^*_ab） of CRP were decreased（P<0.01）， and red-green value（a^*） was increased（P<0.01）， the response values of S4， S5， S10 and S13 sensors were significantly increased（P<0.05）， and the response values of S3 and S8 sensors were significantly decreased（P<0.05）. Correlation analysis showed that α-pinene and β-myrcene were negatively correlated with L^* and E^*_ab， but positively correlated with a^*. Sabinene was positively correlated with L^* and E^*_ab. Linalool was positively correlated with L^* and E^*_ab， and negatively correlated with a^*. The ocimene isomer mixture was positively correlated with the L^*. ConclusionAfter being processed with Halloysitum Rubrum， the appearance color， odor and volatile components of CRP change significantly， and α-pinene， β-myrcene， sabinene， linalool and A-ocimene are the characteristic volatile components before and after processing， which can provide references for the quality evaluation and clinical application of CRP and its processed products.

ObjectiveTo analyze the differences in color， odor and volatile components of Citri Reticulatae Pericarpium（CRP） before and after being stir-fried with Halloysitum Rubrum， and to explore the material basis of enhancing the effect of strengthening spleen after processing and the scientific connotation of decoction pieces processed with Halloysitum Rubrum as the auxiliary material. MethodsThe volatile components of the samples before and after processing were identified and relatively quantified by headspace gas chromatography-mass spectrometry（HS-GC-MS）， and the volatile components were analyzed by principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA）. According to the principle of variable importance in the projection（VIP） value>1.5， volatile differential components before and after processing were screened. And combined with intelligent sensory technologies such as colorimeter and electronic nose， the chroma and odor information of CRP before and after being stir-fried with Halloysitum Rubrum were identified. Pearson correlation analysis was used to explore the correlation between volatile differential components and chroma values. ResultsA total of 112 volatile components were identified from CRP and CRP stir-fried with Halloysitum Rubrum， of which 84 were from CRP and 97 were from CRP stir-fried with Halloysitum Rubrum. And 7 differential components were selected， including α-pinene， β-myrcene， linalool， sabinene， ocimene isomer mixture， A-ocimene， and δ-elemene. After being processed with Halloysitum Rubrum， the brightness value（L^*）， yellow-blue value（b^*） and total chromatic value（E^*_ab） of CRP were decreased（P<0.01）， and red-green value（a^*） was increased（P<0.01）， the response values of S4， S5， S10 and S13 sensors were significantly increased（P<0.05）， and the response values of S3 and S8 sensors were significantly decreased（P<0.05）. Correlation analysis showed that α-pinene and β-myrcene were negatively correlated with L^* and E^*_ab， but positively correlated with a^*. Sabinene was positively correlated with L^* and E^*_ab. Linalool was positively correlated with L^* and E^*_ab， and negatively correlated with a^*. The ocimene isomer mixture was positively correlated with the L^*. ConclusionAfter being processed with Halloysitum Rubrum， the appearance color， odor and volatile components of CRP change significantly， and α-pinene， β-myrcene， sabinene， linalool and A-ocimene are the characteristic volatile components before and after processing， which can provide references for the quality evaluation and clinical application of CRP and its processed products.

Objective:To explore the early and mid-term efficacy of three-dimensional printed customized porous prosthesis with preserved articular in the reconstruction of ultra-long segmental bone defect around the metaphysis of peri-knee.Methods:A retrospective analysis was conducted on the data of 24 patients who underwent reconstruction of ultra-long segmental bone defect around the metaphysis of peri-knee using 3D-printed customized porous prostheses at West China Hospital of Sichuan University from June 2015 to June 2021. There were 14 female cases and 10 male cases, with an average age of 28.9±16.5 years (range, 12-61 years), 12 cases at the distal end of the femur and 12 cases at the proximal end of the tibia. Tumor types: 16 cases of osteosarcoma, 4 cases of Ewing's sarcoma, 2 cases of chondrosarcoma, and 2 case of parosteal osteosarcoma. All patients were classified as Enneking stage IIB. Record the oncology results of the patients, the length of tumor segment resection, and the remaining bone length at the distal femur or proximal tibia, as well as complications, systemic metastasis and imaging changes. The bone integration at the prosthesis-bone interface was evaluated by tomosynthesis-shimadzu metal artifact reduction technology (T-SMART). Limb function was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 score and knee range of motion assessment.Results:All 24 patients successfully completed the surgery and were followed up, with an average follow-up time of 51.8±12.7 months (range, 32-99 months). The length of femoral osteotomy was 241.1±66.2 mm (range, 150.6-333.4 mm), and the length of tibial osteotomy was 198.6±35.6 mm (range, 156.6-287.6 mm). The remaining bone length at the epiphyseal end around the knee joint (from the knee joint plane to the osteotomy plane of the distal femur or proximal tibia) was 52.6±11.0 mm (range, 31.1-77.5 mm). At the last follow-up, 23 patients survived tumor-free, while one patient died due to lung metastasis 54 months after the operation. One patient had prosthesis fracture 75 months after the operation, two patients had aseptic loosening 6 and 8 months after the operation, and the T-SMART of the remaining 20 patients showed that the implanted prostheses all achieved good osseointegration. At the last follow-up, the range of motion of the knee joint was 126.2°±7.5° (range, 110.0°-140.0°), and the MSTS-93 score was 26.7±1.8 points (range, 23-30 points). Among them, the MSTS-93 score of the femoral prosthesis was 26.7±1.6 points (range, 24-29 points), and the MSTS-93 score of the tibial prosthesis was 26.9±1.9 points (range, 23-30 points). The average knee range of motion was 126.2°±7.5° (range, 110°-140°), and the MSTS-93 functional score was 26.7±1.8 points (range, 23-30 points) at the last follow-up. The femoral component had an average score of 26.7±1.6 points (range, 24-29 points), while the tibial component had an average score of 26.9±1.9 points (range, 23-30 points).Conclusion:The application three-dimensional printed customized porous prosthesis with preserved articular in the reconstruction of ultra-long segmental bone defect around the metaphysis of peri-knee can preserve the joint, restore limb function well, and have a low incidence of prosthesis complications, with good clinical efficacy in the early and middle stages.

Objective:To assess the application value of one-hour post-load glucose (1hPG) for detecting prediabetes among individuals with high risk of type 2 diabetes mellitus (T2DM).Methods:The study was conducted between August 2023 and January 2024, and individuals with a high risk of T2DM were invited to receive an oral glucose tolerance test (OGTT), structural questionnaires, physical measurements, and other biochemical examinations. The fasting, one-, and two-hour glucose and insulin were tested. According to the 1hPG cut point on hyperglycemia suggested by International Diabetes Federation (IDF), normal glucose tolerance (NGT) and prediabetes were further divided into two subgroups, respectively, i.e., NGT with 1hPG<8.6 mmol/L (NGT-1hPG-normal), NGT with 1hPG≥8.6 mmol/L (NGT-1hPG-high), prediabetes with 1hPG<8.6 mmol/L (PDM-1hPG-normal), and prediabetes with 1hPG≥8.6 mmol/L (PDM-1hPG-high). The insulin release curve was drawn by the groups as above. Insulin resistance was evaluated by homeostasis model assessment for insulin resistance (HOMA-IR), and β-cell secretory function was evaluated by homeostasis model assessment for β cell function (HOMA-β)/HOMA-IR. Spearman rank correlation analysis was used to calculate the correlation coefficients among 1hPG, 2hPG and HOMA indices, and Steiger′s Z test was used to compare the difference between two correlation coefficients. Receiver operating characteristics (ROC) curves and area under the curve (AUC) were used to assess the accuracy of 1hPG for detecting prediabetes. Results:A total of 2 469 subjects consisting of 1 485 men (60.1%) and 984 (39.9%) women, with a mean age of (45.76±6.20) years, of which 1 844 (74.7%) had 1hPG≥8.6 mmol/L. The prevalence of 1hPG≥8.6 mmol/L was 46.8%, 93.0% and 99.8% in individuals with NGT, prediabetes and newly diagnosed T2DM, respectively ( χ 2=763.78, P<0.001). The insulin release curve showed that insulin secretion increased rapidly in subjects with NGT-1hPG-high, and peaked at one hour, then decreased rapidly, with a significantly higher level of one- and two-hour insulin than those with NGT-1hPG-normal ( P<0.001). Compared to individuals with NGT-1hPG-normal, the counterparts with NGT-1hPG-high exhibited higher HOMA-IR and lower adjusted HOMA-β ( P<0.001). Spearman rank correlation analysis showed that the correlation coefficient of 1hPG with HOMA-IR was similar to the correlation coefficient of 2hPG with HOMA-IR (0.493 vs. 0.480, P=0.550), while the correlation of 1hPG with adjusted HOMA-β was significantly stronger than that of 2hPG (-0.692 vs. -0.587, P<0.001). Excluding patients with T2DM, according to the cut point recommended by IDF, the AUC of 1hPG≥8.6 mmol/L for detecting prediabetes was 0.731 (95% CI: 0.714-0.748), and the sensitivity and specificity were 0.930 and 0.532, respectively, with the kappa value of 0.45. Conclusion:1hPG is closely related to insulin resistance and islet function, and there′s substantial value for individuals with a high risk of T2DM to detect prediabetes by using the 1hPG cut points recommended by IDF.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.