Background 900 MHz radiofrequency radiation (RF) is a commonly used frequency in modern wireless communication devices, and its potential health effects have drawn much attention, especially its impact on bone metabolism, which has not been fully clarified. Objective To investigate the effects of 900 MHz RF on the bone tissue and osteoblast senescence of mice, as well as the dose-effect relationship. Methods In vivo, 3-month-old female C57BL/6 mice were divided into five groups (n=10): sham exposure, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and D-galactose positive control (D-gal). Treatments were administered for 4 h per day for 28 d. Bone mineral density (BMD) and microstructure, including bone volume (BV), tissue volume (TV), bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular separation (Tb.Sp), and trabecular thickness (Tb.Th), were assessed by Micro-CT; bone morphology was examined after hematoxylin and eosin (HE) staining; osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-κΒ ligand (RANKL) expression was detected by immunohistochemistry; serum OPG, tartrate-resistant acid phosphatase 5b (TRACP-5b), plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6), and C-X-C motif chemokine ligand 15 (CXCL15) levels were measured by enzyme-linked immunosorbent assay (ELISA); mRNA expression of Tp53, Cdkn1a, and Cdkn2a in bone tissue was analyzed by reverse transcription polymerase chain reaction (RT-PCR). In vitro, MC3T3-E1 pre-osteoblasts were grouped into sham, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and H₂O₂ control, groups, and were exposed for 4 h per day for 5 d. Cell morphology was observed by microscopy; viability was tested by cell counting kit-8 (CCK-8); senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining; P53 and P21 protein expression was detected by Western blot; Tp53 and Cdkn1a mRNA levels were measured by RT-PCR. Results In vivo, RF at each dose significantly reduced the BMD of the mice's femurs and the bone microstructure parameters, such as BV/TV, Tb.N, and Tb.Th (P<0.05). Among them, Tb.Sp only increased in the 150 μW·cm⁻² RF group (P<0.05), with a looser bone network; fewer, sparser trabeculae and increased marrow fat were observed after HE staining; down-regulated OPG and up-regulated RANKL expression levels were observed by immunohistochemistry; the ELISA test revealed that the serum OPG levels in the 150 μW·cm⁻² RF group and the 450 μW·cm⁻² RF group of mice were significantly decreased (P<0.05), while the indicator in the 50 μW·cm⁻² RF group showed a decreasing trend but the difference was not statistically significant (P>0.05), TRACP-5b rose, and PAI-1, IL-6, and CXCL15 levels increased (P<0.05); the RT-PCR results showed thatTp53, Cdkn1a, and Cdkn2a mRNA expression was upregulated (P<0.05). In vitro, radiofrequency radiation induced cell flattening, reduced viability (P<0.05), increased SA-β-gal-positive cells (P<0.05), and upregulated P53, P21, Tp53, and Cdkn1a expression (P<0.05). Conclusion 900 MHz RF disrupts bone metabolism in mice by inhibiting bone formation, promoting resorption, and inducing osteoblast senescence, accelerating bone aging. The 150 μW·cm⁻² RF dose exhibits the most pronounced effect, reflecting a nonlinear “window effect,” highlighting potential health risks.

Objective To analyze the pathogen species and clinical characteristics in patients with acute up-per respiratory tract infection.Methods A total of 275 patients with acute upper respiratory tract infection admitted to Jinling Hospital,Affiliated Hospital of Medical School,Nanjing University from December 1,2023 to May 15,2024 were selected as research objects.Real-time fluorescence quantitative polymerase chain reac-tion was used to detect pathogen species in throat swab samples,and clinical data and peripheral blood test in-dexes were collected in the medical record system.Results The positive detection rate of influenza A virus was 9.45%,influenza B virus 17.82%,respiratory syncytial virus 9.45%,adenovirus 9.21%,severe acute re-spiratory syndrome coronavirus 2 18.37%,mycoplasma pneumoniae 10.04%,and chlamydia pneumoniae 1.67%.Compared with other age groups,the positive detection rates of influenza A virus,influenza B virus,respiratory syncytial virus,adenovirus,mycoplasma pneumoniae and chlamydia pneumoniae in patients<18 years old were higher,and the difference was statistically significant(P<0.05).The proportion of monocytes in patients infected with influenza B virus was higher than that in patients infected with other pathogens,and the difference was statistically significant(P<0.05).Conclusion Identification the pathogen types of acute upper respiratory tract infection patients is helpful for developing appropriate treatment plans and providing a basis for clinical diagnosis and treatment for the patients.

Objective:To explore the cost-effectiveness and cost-benefit of chronic obstructive pulmonary disease (COPD) screening and intervention based on family doctor contract services.Methods:From January 2023 to October 2023, using purposive sampling and a cross-sectional survey method, 1 040 individuals aged 60 to 75 years who underwent physical examinations at community health service centers in Shanghai Minhang district were selected as research subjects. The subjects were divided into a control group ( n=532) and a study group ( n=508). The control group received conventional community health education and participated in a COPD screening and intervention program provided by the examination center. The study group received COPD screening and intervention provided by contracted family doctors under a tightly integrated medical consortium. The screening content for both groups included initial and follow-up risk assessment questionnaires, pulmonary function tests, bronchodilator tests, and CT scans. A comparative analysis was conducted on the screening compliance rate, positive rate, and cost-effectiveness and cost-benefit between the two groups. Results:A total of 251 individuals at high risk for COPD and confirmed COPD patients were identified through initial and re-screening in both groups, accounting for 24.13% of the subjects, including 222 individuals at high risk (21.35%) and 29 confirmed patients (2.79%). The study group had significantly higher compliance rates in questionnaire-based initial screening, questionnaire-based re-screening+pulmonary function tests, bronchodilator experiments, diagnosis, and subsequent CT scans than the control group ( χ2=33.563, 41.425, 24.842, 17.363, all P<0.05).There were significant higher proportions of high-risk individuals and patients identified through screening in the study group than those in the control group ( χ2=44.880, all P<0.05). The study group had significantly higher positive rates of questionnaire-based initial screening, pulmonary function tests, bronchodilator experiments, and CT scans than the control group ( χ2=29.191, 11.313, 12.370, 4.429, all P<0.05). The overall costs of the screening in the control and study groups were 36 100 and 53 900 yuan, respectively. The cost of pulmonary function tests in the screening for the control and study groups was 1.44 million and 2.45 million yuan, respectively, accounting for 43.19% of the total cost, which was the highest proportion among all costs. The per capita cost for identifying one high-risk individual or patient with COPD was 358.46 Yuan, and the cost in study groups was significantly lower than that in the control group (322.75 vs. 429.45 yuan, χ2=20.396, P<0.05). The per capita net benefits and cost-benefit ratios for the overall subjects in the two groups were 0.37 million yuan and 43.50, respectively. The average net benefit of the study group and the control group was 0.49 million yuan and 0.26 million yuan respectively. The average net benefit of the study group was 0.23 million yuan higher than that of the control group. The cost-benefit ratio of the study group and the control group were 46.77 and 38.61, respectively. The cost-benefit ratio of the study group was 8.16 higher than that of the control group. Conclusion:The screening and intervention for COPD based on family doctor contract services have significant effectiveness, with a marked improvement in screening compliance and high cost-effectiveness, and can be used in community medical institutions with relatively sound family doctor and medical consortium services for targeted COPD screening.