Objective To investigate the epidemiological characteristics of dengue fever in Shenzhen City in 2024, so as to provide insights into formulation of the preventive and control measures for dengue fever. Methods The epidemiological data of dengue cases reported in Shenzhen City in 2024 were extracted from the China Disease Prevention and Control Information System and field epidemiological survey data of dengue fever in Shenzhen City, and the temporal, regional and population distributions of dengue fever cases, source of acquire dengue virus infections, disease diagnosis and treatment and outbreaks were analyzed. The dengue virus nucleic acid was tested and the serotypes of dengue virus were characterized using real-time quantitative reverse transcription PCR (RT-qPCR) assay, and the dengue virus gene was sequenced using next-generation sequencing (NGS). In addition, the surveillance on the density of Aedes albopictus was performed using Breteau index (BI) and mosquito oviposition index (MOI). Results A total of 1 735 dengue fever cases were reported in Shenzhen City in 2024, including 952 local cases and 783 imported cases. Most imported dengue fever cases acquired infections from eight cities of Foshan, Guangzhou, Zhongshan, Jiangmen, Dongguan, Zhaoqing, Huizhou, and Zhuhai in the Pearl River Delta region (664 cases, 84.8% of total imported cases) into Baoan, Longgang, and Nanshan districts. The epidemic exhibited an early onset and rapid progression, peaking during the period between September and November (1 632 cases, 94.1% of total cases), and dengue fever cases were distributed across 73 subdistricts in 10 districts, with most cases reported in densely populated central and western regions. The dengue fever cases had a male-to-female ratio of 1.9∶1.0, and a median age of 37 (21) years, with a higher median age among local cases than among imported cases [40 (20) years vs. 33(15) years; Z = -10.30, P < 0.05]. Housework, unemployment, workers, and business service were predominant occupations (1 405 cases, 81.0% of total cases), and there was a significant difference in the constituent ratio of occupations between local and imported cases (χ² = 92.30, P < 0.05). Among the 1 735 dengue fever cases, the median duration from onset to definitive diagnosis was 3.3 (2.9) days, and 1 686 cases (97.2%) were identified in healthcare facilities, with a low rate of hospitalization and isolation seen in 1 701 inpatients with available epidemiological data (485 cases, 28.5% of total inpatients). A total of 29 outbreaks of dengue fever occurred in Shenzhen City across 2024, which primarily in construction sites (27 outbreaks, 93.1% of total). Dengue virus type I was the dominant serotype causing dengue fever in Shenzhen City in 2024. Sequencing showed that the genomes of dengue virus from multiple dengue fever cases in Shenzhen City shared a high sequence homology with those from cities neighboring Shenzhen City, and there might be intra-city transmission of dengue virus among multiple construction sites in Shenzhen City. The Aedes albopictus density was significantly higher in Shenzhen City in 2024 than in 2023, peaking from May to September. The annual MOI values ranged from 0.9 to 14.0, and the BI values ranged from 0.6 to 6.0. Conclusions The overall epidemic of dengue fever was severe in Shenzhen City in 2024, which was greatly affected by case importation from neighboring cities, construction sites-centered local transmission, and the effectives of routine mosquito vector control was not satisfactory. Integrated dengue fever control measures should be implemented, focusing on regional joint prevention and control mechanisms, capacity building for mosquito vector control, addressing challenges in epidemic containment at construction sites, and strengthening case detection and management systems.

With the intensification of the aging population phenomenon, the rehabilitation of elderly patients with cardiovascular diseases has become a top priority.Exercise Preconditioning(EP), as a form of exercise rehabilitation that generates myocardial protective effects, has been extensively researched.This paper adopts the literature review method to focus on summarizing the research progress of classical EP in cardiovascular rehabilitation for elderly patients.Classical EP refers to a single process in which repeated short bouts of high-intensity interval training(HIIT)lead to relative or absolute ischemia and hypoxia in the body, inducing the body to produce endogenous myocardial protective effects.This enhances the body's tolerance to ischemia and hypoxia, thereby protecting it from subsequent sustained ischemic-hypoxic injury.As a form of EP, HIIT has been widely recognized for its ability to induce myocardial protective effects.By summarizing its clinical protective effects and mechanisms, as well as the application of EP in the exercise rehabilitation protocols for elderly patients with cardiovascular diseases, this paper aims to provide more effective exercise rehabilitation guidance for elderly patients and reduce exercise-induced cardiovascular injuries.

Osteoarthritis is a chronic degenerative disease characterized by cartilage degeneration, synovial inflammation, and subchondral bone remodeling. Its pathogenesis involves multiple links such as joint mechanical stress imbalance, extracellular matrix degradation, and inflammatory responses. Physical exercise has been widely recognized in the treatment of osteoarthritis. Although mechanism of action remains incompletely understood, appropriate exercise can effectively relieve pain caused by osteoarthritis, improve joint dysfunction, and reduce inflammation. In recent years, pyroptosis has been proven to exacerbate the pathological process of osteoarthritis by promoting the release of pro-inflammatory factors such as IL-1β and HMGB1 from synovial fibroblasts (FLSs) and chondrocytes. The pyroptosis of FLSs is regulated by the NLRP1/3 inflammasome, HIF-1α, and the SDF-1/AMPK pathway. In contrast, chondrocyte pyroptosis is closely related to the activation of the P2X7 receptor, the NF-κB/NLRP3 signaling axis, microRNAs (for example, miR-140-5p inhibits CTSB/NLRP3, while miR-155 promotes pyroptosis), and certain traditional Chinese medicine extracts (such as morroniside and loganin). Both exercise and pyroptosis are closely associated with the inflammatory response in osteoarthritis. Recent studies have found that exercise/mechanical stress stimulation can directly or indirectly regulate chondrocyte pyroptosis and delay the progression of osteoarthritis. In terms of direct regulation, moderate-intensity exercise can downregulate the expression of the P2X7 receptor, activate the AMPK/mTOR pathway to promote autophagy, and thereby inhibit chondrocyte pyroptosis. Mechanical stretch stimulation can upregulate TGF-β1 to activate the Smad2/3 pathway and inhibit the NF-κB/NLRP3 signaling axis. In terms of indirect regulation, exercise can inhibit the PI3K/Akt/NF-κB pathway by increasing the secretion of irisin, and simultaneously promote the production of lipoxin A4 (LXA4) to induce the polarization of synovial macrophages into the anti-inflammatory M2 type. In addition, exercise can also upregulate the expression of Metrnl protein and block the NLRP3/caspase-1/GSDMD pyroptosis signaling cascade.

Osteoarthritis is a chronic degenerative disease characterized by cartilage degeneration, synovial inflammation, and subchondral bone remodeling. Its pathogenesis involves multiple links such as joint mechanical stress imbalance, extracellular matrix degradation, and inflammatory responses. Physical exercise has been widely recognized in the treatment of osteoarthritis. Although mechanism of action remains incompletely understood, appropriate exercise can effectively relieve pain caused by osteoarthritis, improve joint dysfunction, and reduce inflammation. In recent years, pyroptosis has been proven to exacerbate the pathological process of osteoarthritis by promoting the release of pro-inflammatory factors such as IL-1β and HMGB1 from synovial fibroblasts (FLSs) and chondrocytes. The pyroptosis of FLSs is regulated by the NLRP1/3 inflammasome, HIF-1α, and the SDF-1/AMPK pathway. In contrast, chondrocyte pyroptosis is closely related to the activation of the P2X7 receptor, the NF-κB/NLRP3 signaling axis, microRNAs (for example, miR-140-5p inhibits CTSB/NLRP3, while miR-155 promotes pyroptosis), and certain traditional Chinese medicine extracts (such as morroniside and loganin). Both exercise and pyroptosis are closely associated with the inflammatory response in osteoarthritis. Recent studies have found that exercise/mechanical stress stimulation can directly or indirectly regulate chondrocyte pyroptosis and delay the progression of osteoarthritis. In terms of direct regulation, moderate-intensity exercise can downregulate the expression of the P2X7 receptor, activate the AMPK/mTOR pathway to promote autophagy, and thereby inhibit chondrocyte pyroptosis. Mechanical stretch stimulation can upregulate TGF-β1 to activate the Smad2/3 pathway and inhibit the NF-κB/NLRP3 signaling axis. In terms of indirect regulation, exercise can inhibit the PI3K/Akt/NF-κB pathway by increasing the secretion of irisin, and simultaneously promote the production of lipoxin A4 (LXA4) to induce the polarization of synovial macrophages into the anti-inflammatory M2 type. In addition, exercise can also upregulate the expression of Metrnl protein and block the NLRP3/caspase-1/GSDMD pyroptosis signaling cascade.

With the intensification of the aging population phenomenon, the rehabilitation of elderly patients with cardiovascular diseases has become a top priority.Exercise Preconditioning(EP), as a form of exercise rehabilitation that generates myocardial protective effects, has been extensively researched.This paper adopts the literature review method to focus on summarizing the research progress of classical EP in cardiovascular rehabilitation for elderly patients.Classical EP refers to a single process in which repeated short bouts of high-intensity interval training(HIIT)lead to relative or absolute ischemia and hypoxia in the body, inducing the body to produce endogenous myocardial protective effects.This enhances the body's tolerance to ischemia and hypoxia, thereby protecting it from subsequent sustained ischemic-hypoxic injury.As a form of EP, HIIT has been widely recognized for its ability to induce myocardial protective effects.By summarizing its clinical protective effects and mechanisms, as well as the application of EP in the exercise rehabilitation protocols for elderly patients with cardiovascular diseases, this paper aims to provide more effective exercise rehabilitation guidance for elderly patients and reduce exercise-induced cardiovascular injuries.

Objective To investigate the effects of a chitosan product on scarring and adhesion after never injury in laminectomy in rats. Methods 48 male Sprague-Dawley rats were divided into group A and group B, and carried laminectomy of L4-5, and injured the right spinal nerve roots. The normal saline was smeared on the operation field in the group A, while the chitosan product was smeared in the group B. The adhesion was assessed with Rydell score 1 (groups A1/B1), 2 (groups A2/B2) and 4 (groups A3/B3) weeks after operation, while the spinal nerves were observed with HE staining and Masson staining, and the adhesion was assessed with Nussbaum score. The complete blood count and the series of blood chemistries and enzymes for liver and kidney functioning were measured. Results The Rydell scores of adhesion was I grade in group A1, II grade in A2 and III grade in A3, while was 0 grade in B1, 0 grade in B2 and II grade in B3. The scar and adhesion contact more loosely in the group B than in the group A, and the Nussbaum score was less in the group B than in the group A at the same time (P<0.05). The complete blood count and the series of blood chemistries and enzymes for liver and kidney functioning were in normal. Conclusion This chitosan product can prevent the formation of epidural scar and adhesion around the spinal and the nerve roots after laminectomy, with little toxicity and side effects.