Objective To investigate the epidemiological characteristics and effectiveness of emergency responses to epidemic foci in Guangzhou City in 2024, so as to optimization of the dengue fever control strategy in Guangzhou City. Methods All data pertaining to dengue fever cases in Guangzhou City in 2024 were collected from the National Notifiable Infectious Disease Surveillance Information Reporting System. The temporal, spatial and population distributions of dengue fever cases and sources of infections were descriptively analyzed, and the effectiveness of emergency responses to epidemic foci of dengue fever was evaluated through standard space index (SSI), the interval from disease onset to case reporting and the percentage of isolation in hospital. Results A total of 3 656 dengue fever cases were reported in Guangzhou City in 2024, including 3 102 local cases and 554 imported cases. Of all cases, 67.86% (2 481 cases) occurred at ages of 20 to 59 years, and the three most common occupations included housework/unemployment (793 cases, 21.69%), business servants (744 cases, 20.35%) and retirees (669 cases, 18.30%). The peak of dengue fever epidemics was concentrated during the period from the 39th to the 45th weeks in 2024, when a total of 2 317 local cases were reported, accounting for 74.69% of all local cases in 2024. Dengue fever cases were reported across all 11 districts in Guangzhou City in 2024, with local cases concentrated in Baiyun District (754 cases, 24.31%), Liwan District (398 cases, 12.83%), Panyu District (365 cases, 11.77%), Haizhu District (332 cases, 10.70%) and Tianhe District (328 cases, 10.57%). Imported dengue fever cases were predominantly domestically imported (492 cases, 88.81%), with the majority imported from Foshan City (377 cases), and overseas imported cases were predominantly imported from southeastern Asian countries. The mean proportion of case isolation in hospital was 9.16% (284/3 102), and the mean interval from disease onset to case reporting was (3.99 ± 2.70) days, while the percentages of mosquito density meeting the required standard were 61.68% (462/ 749) and 66.32% (126/190) on the 4th and 7th day of emergency responses to epidemic foci, respectively. Conclusions The prevention and control cycle of dengue fever in Guangzhou in 2024 took longer than in previous years, with a larger scale of the epidemic. Although some progress has been made in epidemic management, there are still problems such as unsustainable mosquito vector control and low hospitalization isolation rates for cases. Further optimization of control measures in mosquito vector control, case monitoring and management is required to improve the effectiveness of dengue fever control measures.

Objective:To investigate alterations in the immune lineage of T-cell large granular lymphocytic leukemia (T-LGLL) at the single-cell transcriptome level and to elucidate its pathogenic mechanisms.Methods:Peripheral blood samples were collected from 5 T-LGLL patients before and after treatment (from June 2019 to December 2020) and 3 healthy controls at the Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC. Single-cell transcriptome sequencing libraries were prepared and sequenced using 10× Genomics technology. Differentially expressed genes in immune cells were compared between patients and healthy donors, followed by pathway enrichment analyses.Results:Profiling 67,237 immune cells revealed that, in T-LGLL: 1) Effector CD8+ T cells exhibited increased numbers, enhanced cytotoxicity, and greater proliferative capacity. Following effective immunosuppressive therapy, both the proliferative capacity and effector functions of these cells significantly decreased ( P<0.05). 2) The proportion of regulatory T (Treg) cells was reduced, accompanied by increased apoptosis. After effective immunosuppressive therapy leading to remission, Treg cell proportions increased, and apoptotic pathways were downregulated ( P<0.05). 3) Antigen-presenting cells (APCs) showed enhanced functionality. Monocytes and dendritic cells were enriched in antigen synthesis and presentation pathways, while B cells displayed increased antigen-binding capacity and were enriched in pathways related to T-cell activation ( P<0.05). 4) Natural killer (NK) cells exhibited attenuated cytotoxic function but demonstrated an enhanced regulatory capacity over T cells ( P<0.05) . Conclusions:T-LGLL patients present a characteristic immunological profile marked by an imbalance in immune homeostasis. This profile includes abnormal activation and expansion of effector CD8 + T cells, and a reduction in Treg cell numbers accompanied by functional impairment. Furthermore, APCs and NK cells were found to positively regulate T-lymphocyte activation, differentiation, and proliferation.

Objective:To evaluate the efficacy of cyclophosphamide in patients with T-cell large granular lymphocytic leukemia (T-LGLL) and the maintenance of treatment-free remission (TFR) following drug discontinuation.Methods:Clinical data were collected from 37 patients with T-LGLL who received oral cyclophosphamide at the Regenerative Medicine Clinic of the Institute of Hematology and Blood Diseases Hospital between June 2019 and March 2024. Patient clinical characteristics, treatment efficacy, and long-term TFR were analyzed.Results:The median age of the 37 patients was 60 years (range: 37-86), and 22 (59.5%) were male. Anemia was observed in 30 patients (81.1%), and 28 (75.7%) met the diagnostic criteria for secondary pure red cell aplasia. Neutropenia occurred in 15 patients (40.5%), lymphocytosis in 11 (29.7%), and thrombocytopenia in three (8.1%). Sixteen patients (43.2%) had not received prior immunosuppressive therapy (treatment-naive group), while 21 patients (56.8%) were refractory to or had relapsed after immunosuppressive treatment (refractory/relapsed group). All patients met the treatment criteria and received oral cyclophosphamide at doses of 50-100 mg/day. Among the 36 evaluable patients, hematologic remission was achieved in 25 (69.4%), with a median time of 2.0 months (range: 0.7-7.0). There was no statistically significant difference in remission rates between the treatment-naive and refractory/relapsed groups (68.5% vs. 66.7%, P=0.589). Among the 25 patients who achieved hematologic remission, 24 discontinued cyclophosphamide. With a median follow-up of 39.0 months (range: 8.0-56.0), the median TFR duration was not reached. The estimated TFR rates were (90.87± 6.16) % at 12 months and (75.72±11.04) % at 36 months. No significant difference in TFR was observed between the treatment-naive and refractory/relapsed groups ( P=0.451) . Conclusion:Oral cyclophosphamide is effective in the treatment of T-LGLL, and patients may maintain long-term TFR following drug discontinuation.

Objective:To investigate alterations in the immune lineage of T-cell large granular lymphocytic leukemia (T-LGLL) at the single-cell transcriptome level and to elucidate its pathogenic mechanisms.Methods:Peripheral blood samples were collected from 5 T-LGLL patients before and after treatment (from June 2019 to December 2020) and 3 healthy controls at the Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC. Single-cell transcriptome sequencing libraries were prepared and sequenced using 10× Genomics technology. Differentially expressed genes in immune cells were compared between patients and healthy donors, followed by pathway enrichment analyses.Results:Profiling 67,237 immune cells revealed that, in T-LGLL: 1) Effector CD8+ T cells exhibited increased numbers, enhanced cytotoxicity, and greater proliferative capacity. Following effective immunosuppressive therapy, both the proliferative capacity and effector functions of these cells significantly decreased ( P<0.05). 2) The proportion of regulatory T (Treg) cells was reduced, accompanied by increased apoptosis. After effective immunosuppressive therapy leading to remission, Treg cell proportions increased, and apoptotic pathways were downregulated ( P<0.05). 3) Antigen-presenting cells (APCs) showed enhanced functionality. Monocytes and dendritic cells were enriched in antigen synthesis and presentation pathways, while B cells displayed increased antigen-binding capacity and were enriched in pathways related to T-cell activation ( P<0.05). 4) Natural killer (NK) cells exhibited attenuated cytotoxic function but demonstrated an enhanced regulatory capacity over T cells ( P<0.05) . Conclusions:T-LGLL patients present a characteristic immunological profile marked by an imbalance in immune homeostasis. This profile includes abnormal activation and expansion of effector CD8 + T cells, and a reduction in Treg cell numbers accompanied by functional impairment. Furthermore, APCs and NK cells were found to positively regulate T-lymphocyte activation, differentiation, and proliferation.

Objective:To evaluate the efficacy of cyclophosphamide in patients with T-cell large granular lymphocytic leukemia (T-LGLL) and the maintenance of treatment-free remission (TFR) following drug discontinuation.Methods:Clinical data were collected from 37 patients with T-LGLL who received oral cyclophosphamide at the Regenerative Medicine Clinic of the Institute of Hematology and Blood Diseases Hospital between June 2019 and March 2024. Patient clinical characteristics, treatment efficacy, and long-term TFR were analyzed.Results:The median age of the 37 patients was 60 years (range: 37-86), and 22 (59.5%) were male. Anemia was observed in 30 patients (81.1%), and 28 (75.7%) met the diagnostic criteria for secondary pure red cell aplasia. Neutropenia occurred in 15 patients (40.5%), lymphocytosis in 11 (29.7%), and thrombocytopenia in three (8.1%). Sixteen patients (43.2%) had not received prior immunosuppressive therapy (treatment-naive group), while 21 patients (56.8%) were refractory to or had relapsed after immunosuppressive treatment (refractory/relapsed group). All patients met the treatment criteria and received oral cyclophosphamide at doses of 50-100 mg/day. Among the 36 evaluable patients, hematologic remission was achieved in 25 (69.4%), with a median time of 2.0 months (range: 0.7-7.0). There was no statistically significant difference in remission rates between the treatment-naive and refractory/relapsed groups (68.5% vs. 66.7%, P=0.589). Among the 25 patients who achieved hematologic remission, 24 discontinued cyclophosphamide. With a median follow-up of 39.0 months (range: 8.0-56.0), the median TFR duration was not reached. The estimated TFR rates were (90.87± 6.16) % at 12 months and (75.72±11.04) % at 36 months. No significant difference in TFR was observed between the treatment-naive and refractory/relapsed groups ( P=0.451) . Conclusion:Oral cyclophosphamide is effective in the treatment of T-LGLL, and patients may maintain long-term TFR following drug discontinuation.

Abstract: Objective　To analyze the epidemiological characteristics of dengue fever in Guangzhou and provide a scientific basis for dengue fever prevention and control. Methods　The data of dengue cases in Guangzhou, Guangdong Province reported between 2019 and 2023, were retrieved from the China Disease Prevention and Control Information System. Cross-sectional analysis was used to describe the temporal, spatial, and demographic distribution, and analyze the epidemiological characteristics. Results　A total of 3 518 cases of dengue fever were reported in Guangzhou from 2019 to 2023, including 3 101 local cases (88.15%) and 417 imported cases (11.85%). The annual average incidence rate ranged from 0.09 to 17.59 per 100 000 population. Imported dengue fever cases were reported in all months, with the peak reported from May to November (374 cases, 89.69%). Local cases were first reported in May and the last in December, with the highest incidence from August to November (2 960 cases, 95.45%). The cases were reported in all 11 administrative districts; the top three were Baiyun District, Yuexiu District, and Liwan District. Male and female cases accounted for 53.52% and 46.48%, respectively; the age group mainly concentrated between 20-<60 years (2 547 cases, 72.40%). The top three occupations were business services (784 cases), housework and unemployment (738 cases), and retirees (596 cases). The average time from onset to diagnosis for local cases was 4.06 days, and 4.60 days for imported cases. The overseas imported cases mainly came from Southeast Asia 88.10%(311/353), with the most being imported from Cambodia. Cases imported from other provinces mainly came from Yunnan Province, and cases imported from other cities within the province mainly came from Foshan City. Conclusions　In recent years, the incidence of dengue fever in Guangzhou has remained at a high level, with obvious imported and seasonal characteristics. Relevant departments should pay attention to key populations and take effective measures to reduce the density of mosquito vectors, and strictly prevent the spread of dengue fever.

AIM:To predict the active compo-nents and targets of Piperlongum L.and the associ-ated signaling pathways involved in pulmonary fi-brosis using network pharmacology and molecular docking technique and evaluate the mechanism of Piperlongum L against pulmonary fibrosis by in vi-tro experiments.METHODS:The active ingredients and targets were retrieved from TCMSP,Swiss Tar-get Prediction and PubChem databases.The dis-ease-related targets were retrieved from Gene-Cards and OMIM databases.The intersection tar-gets of the drugs and disease-related targets were identified using jvenn online tool.String database was used to construct the"drug-component-tar-get"and PPI network and the networks were visual-ized using Cytoscape 3.9.1 software.GO and KEGG enrichment analysis were performed on the inter-section targets using the DAVID tool.The top 20 KEGG pathways,core targets and drug components were used to construct a"component-target-path-way"network and the network visualization was performed using Cytoscape 3.9.1 software.The in-teractions between drug compounds and the tar-gets were evaluated by molecular docking,and the docking results were visualized using Discovery stu-dio.HFL-1 cells were cultured and the effect of the drug compounds on cell viability was determined by MTT assay.The inhibition rate was then calculat-ed to determine the optimal drug concentration.HFL-1 cells were cultured in vitro and were as-signed into 4 groups:control group,TGF-β1 group,TGF-β1+LD group(LD group),TGF-β1+HD group(HD group).CCK-8 kit was used to evaluate the anti-proliferative activity of the drug compounds against HFL-1 cells at 24,48 and 72 h.Plate clone formation assay was performed to evaluate the ef-fect of drugs on the colony formation ability of HFL-1 cells.RT-qPCR and western blot were conducted to determine the effect of the compounds on the mRNA and protein expression levels of α-smooth muscle actin(α-SMA),collagen type Ⅰ(COI-Ⅰ),and collagen type Ⅲ(COI-Ⅲ)in each group.RESULTS:A total of 197 intersection targets of Piperlongum L and anti-pulmonary fibrosis were identified.The core PPI network comprised 29 nodes(targets)and 199 edges(interactions).GO functional analysis showed that the significantly enriched biological processes associated with the compounds in Piper-longum L included negative regulation of apopto-sis,signal transduction,and protein phosphoryla-tion.Significantly enriched cellular components in-cluded cytoplasm,nuclear cytoplasm,plasma mem-brane.Enriched molecular functions associated with the compounds included the same protein binding,serine/threonine/tyrosine kinase activity,and protein binding.A total of 155 significantly en-riched KEGG signaling pathways were identified,with PI3K-Akt signaling pathway was highly associ-ated with PF and was the fourth most enriched pathway.PIK3CA,MAPK3,MAPK1,MTOR,SRC,CCND1,EGFR,PRKCA,BCL2,and GSK3B had the highest connectivity in the components-target-pathway network.Piperlongine,N-(2,5-dimethoxy-phenyl)-4-methoxybenzamide,tetrahydrotanshi-none,pisigenin and piperine were the key com-pounds in Piperlongum L.The molecular docking results showed that all the compounds except N-(2,5-dimethoxyphenyl)-4-methoxybenzamide had good binding activities with interactions observed with 10 proteins.The proliferation ability of the cells in the LD group was significantly lower than that of the TGF-β1 group at 48 h and 72 h(P＜0.05).The proliferation ability of cells HD group was sig-nificantly lower than the LD group at 24,48 and 72 h.The number of clones in each drug group was significantly reduced after treatment with the drugs(P＜0.05).The mRNA and protein expression levels of α-SMA,COI-Ⅰ,COI-Ⅲ in LD and HD groups were significantly lower than the expression levels in the TGF-β1 group.The protein expression levels of p-PI3K/PI3K and p-Akt/AKT were significantly lower in the two dose groups compared with the TGF-β1 group(P＜0.01).CONCLUSION:The results showed that the effect of Piperlongum L against PF is probably through modulation of the PI3K-Akt sig-naling pathway.

Objective:To understand the epidemiological characteristics of mpox epidemic in Guangzhou and provide scientific evidence for the prevention and control of the disease.Methods:Based on the mpox surveillance system in Guangzhou, suspected mpox cases with fever and rash were reported by local hospitals at all levels to centers for disease control and prevention in Guangzhou for sampling, investigation and diagnosis. Descriptive epidemiological analysis was conducted on the clinical characteristics and treatment of the mpox cases and positive detection rate reported in Guangzhou as of 24:00 on June 23. Whole genome sequencing of the virus isolates was performed using Illumina Miniseq high-throughput sequencing platform.Results:The first mpox case in Guangzhou was reported on June 10 in 2023. As of 24:00 on June 23, a total of 25 confirmed mpox cases were reported. All the mpox cases were men with a M( Q1, Q3) of 32 (26, 36) years, the majority of the cases were MSM (96.0%). The main clinical features were rash (100.0%, 25/25), lymphadenectasis (100.0%, 25/25) and fever (52.0%, 13/25). Rash usually occurred near the genitals (88.0%, 22/25). The close contacts, mainly family members (40.4%, 23/57), showed no similar symptoms, such as fever or rash. The positive rate of mpox virus in household environment samples was 30.5%. The analyses on 3 complete gene sequences of mpox virus indicated that the strains belonged to West African type Ⅱb clade, B.1.3 lineage. Conclusions:Hidden transmission of mpox virus had occurred in MSM in Guangzhou. However, the size of affected population is relatively limited, and the possibility of wide spread of the virus is low.

Objective:To establish an index system of population based SARS-CoV-2 nucleic acid screening, and provide reference to determine the screening coverage appropriately.Methods:The literature review and brain storming sessions were used to develop the basic frame and index system of population based SARS-CoV-2 nucleic acid screening. Based on Delphi method and Analytic Hierarchy Process, 21 domestic experts were selected for two rounds of consultation to determine the index system of population based SARS-CoV-2 nucleic acid screening and its weight.Results:The positive indexes of experts in two rounds of consultations were both 100%. The experts' authority coefficients ( Cr) were 0.88±0.08 and 0.89±0.07, respectively. And the range of coefficient of variation ( CV) were (0.08, 0.24), (0.09, 0.25). The Kendall's W coordination coefficients were 0.34 and 0.22 respectively, which were statistically significant. The index system of population based SARS-CoV-2 nucleic acid screening was established, which had 4 first-level indexes, 11 second-level indexes and 58 third-level indexes. Besides, the weight of each index was determined. Conclusion:The index system of population based SARS-CoV-2 nucleic acid screening has been established, which can provide scientific reference for the health administration to determine the coverage of population based SARS-CoV-2 nucleic acid screening when local COVID-19 epidemic occurs.

Objective:To understand the epidemiological characteristics of imported COVID-19 cases in Guangzhou and provide scientific basis for the prevention and control of the disease.Methods:The data of imported COVID-19 in Guangzhou reported as of April 1, 2020 were collected from National Notifiable Disease Report System of China. The software Excel 2010 and SPSS 19.0 were applied for data cleaning and statistical analysis.Results:As of April 1, 2020, a total of 103 imported COVID-19 cases had been reported in Guangzhou, in which 92 were confirmed cases and 11 were asymptomatic infection cases. The number of the confirmed imported cases accounted for 11.4 % (92/806) in of the total in China at the same time. The male to female ratio of the cases was 1.58∶1 (63∶40). The median age of the cases was 31 years ( P 25- P 75:22-40 years), range of age was 11-63 years. The main occupational distributions of the cases were business services (41/103, 39.8 %) and students (36/103, 35.0 %). The imported cases whose destinations were 19 provinces and municipalities rather than Guangdong after entering the country accounted for 43.7 %. The main source countries of infections were the United Kingdom (27/103, 26.2 %), the Philippines (13/103, 12.6 %), the United States (13/103, 12.6 %) and Nigeria (7/103, 6.8 %). There were 34 inbound flights from which the imported COVID-19 cases were detected, in which 10 flights (10/34, 29.4 %) were found to carry more than 3 cases, with an average voyage time of (11.14±0.53) hours. A total of 29 imported cases(28.2 %) showed symptoms before entering the country, and 65 cases (63.1 %) had been isolated before the onset of the disease. The mean free activity time of the isolated cases after the onset was (6.76±0.79) days. The average number of the imported cases’ close contacts was 53. There were 13 clusters of COVID-19 caused by the imported cases, involving 36 cases (including 1 imported associated case). Conclusions:The sources of the imported COVID-19 cases in Guangzhou were widely distributed, and no cases had been found to be infected on the flights. In the early stage of the imported epidemic, there was high risk for the spread of the epidemic. Strengthened prevention and control of imported COVID-19 effectively reduced the of transmission risk of COVID-19 in communities.