Purpose: Dual anti–human epidermal growth factor receptor 2 (HER2) drugs have become the standard regimen for neoadjuvant systemic treatment (NST) to HER2-positive breast cancer patients. However, the efficacy varies greatly among patients with different HER2 protein expression levels. Materials and Methods: A total of 575 HER2-positive breast cancer patients from multiple centers throughout China from 2013 to 2022 were retrospectively analyzed. We compared clinicopathological features in different HER2 immunohistochemistry classes (HER2 2+/in situ hybridization [ISH] + or HER2 3+), and their difference in response to NST and survival with single or dual anti-HER2 drugs. Drug sensitivity assays were used to evaluate different efficacy of anti-HER2 drugs in vitro. Results: Compared to HER2 3+ subgroup, the HER2 2+/ISH+ group had a higher proportion of hormone receptor–positive status (48.7% vs. 76.1%, p < 0.001), more HER2 protein loss after NST, lower pathological complete response (pCR) rate (46.07% vs. 16.24%, p < 0.001), and tended to have worse disease-free survival (DFS). In HER2 2+/ISH+ patients, treated with pertuzumab and trastuzumab in combination had no significant improvement in pCR (19.12% vs. 12.24%, p=0.287) and DFS (p=0.908) than using alone. Drug sensitivity assay showed poor efficacy with dual anti-HER2 drugs in HER2 2+/ISH+ cell lines; however, fam-trastuzumab deruxtecan drugs had a satisfactory effect. Conclusion Owing to the differences in clinicopathological features and treatment efficacy, we considered the HER2 2+/ISH+ group to be a distinct subtype and defined it as the HER2-moderate–positive subgroup. In this subgroup, dual anti-HER2 drugs did not exert significant improvement in pCR and DFS. Therefore, treatment optimization is warranted, with antibody-drug conjugate drugs as potential options.

Objective To investigate the value of adjusting antiplatelet treatment regimens guided by thromboelastography(TEG)in predicting cerebral ischemic events after stent-assisted embolization of intracranial aneurysms.Methods This study retrospectively and consecutively enrolled patients with intracranial aneurysms who underwent stent-assisted coil embolization admitted to the Department of Neurosurgery of the General Hospital of Eastern Theater Command,from March 2022 to May 2024.Baseline and clinical data of the patients,including gender,age,hypertension,diabetes,dyslipidemia,smoking history,drinking history,and intraoperative use of tirofiban were collected.Antiplatelet therapy(conventional dose aspirin[100 mg once daily]+clopidogrel[75 mg once daily])was initiated immediately after the diagnosis of intracranial aneurysm,and TEG was performed 3 days later.According to the platelet inhibition rate in TEG parameters(platelet inhibition rate induced by arachidonic acid[AA]pathway[AA inhibition rate]or adenosine diphosphate[ADP]pathway[ADP inhibition rate],AA inhibition rate ≥ 50％indicated aspirin effectiveness,AA inhibition rate＜50％indicated aspirin resistance;ADP inhibition rate ≥ 30％indicated clopidogrel effectiveness,ADP inhibition rate＜30％indicated clopidogrel resistance),the patients were divided into the control group(TEG test results met the criteria,i.e.,AA inhibition rate ≥ 50％and ADP inhibition rate ≥ 30％),the conventional dual antiplatelet therapy group(TEG test results did not meet the criteria but were not adjusted for antiplatelet therapy,i.e.,AA inhibition rate＜50％and/or ADP inhibition rate＜30％,but with complex aneurysm morphology[such as irregular shape,daughter sac formation]or high bleeding risk,continuing conventional dual antiplatelet therapy),and the intensified group(TEG test results did not meet the criteria and the antiplatelet therapy regimen was adjusted,i.e.,AA inhibition rate＜50％and/or ADP inhibition rate＜30％,adjusting the antiplatelet therapy regimen).All patients underwent stent-assisted coil embolization after TEG testing.From 0 to 3 months after the operation,all three groups maintained the above antiplatelet therapy.At 3 months after the operation,routine head MRI,CT and other examinations were performed.If no cerebral ischemic events occurred and the imaging results were satisfactory(good stent position,no aneurysm occlusion residual or slight residual at the neck[neck width of the aneurysm 2mm]),the treatment could be adjusted to single antiplatelet therapy(aspirin 100 mg once daily).If a patient experienced a cerebral ischemic event during the follow-up period,regardless of the stage after the operation,dual antiplatelet therapy(aspirin[100mg once daily]+clopidogrel[75 mg once daily])was immediately restarted or maintained and continued for at least 6 months.The primary endpoint was intraoperative and 6-months postoperative cerebral ischemic events(including DSA-confirmed intraoperative acute thrombosis and infarction foci confirmed by head CT or MRI).Baseline and clinical data of the three groups were compared.All patients were divided into groups with ischemic stroke event and without according to the primary endpoint,univariate Logistic regression analysis was then performed on both groups.Variables with P＜0.1 in the univariate Logistic regression analysis were included in the multivariate Logistic regression analysis to explore the influencing factors of cerebral ischemic events after stent-assisted coil embolization for intracranial aneurysms.Results A total of 499 patients were included,including 178 males and 321 females,with a median age of 59(53,68)years.Among them,there were 341 patients in the control group,42 in the conventional dual antiplatelet therapy group,and 116 in the intensified group.There were 47 cases of cerebral ischemic events and 452 cases without cerebral ischemic events.There was a statistically significant difference in the intraoperative use rate of tirofiban across the control group,the conventional dual antiplatelet therapy group,and the intensified group(20.2％[69/341]vs.26.2％[11/42]vs.42.2％[49/116],P＜0.01);no statistically significant differences were observed among the three groups in terms of age,gender composition,the proportion of patients with hypertension,diabetes,dyslipidemia,smoking history,drinking history,and the incidence of cerebral ischemic events(all P＞0.05).The results of multivariate Logistic regression analysis showed that hypertension(OR,2.924,95％CI 1.416-6.037,P=0.004)and intraoperative use of tirofiban(OR,3.638,95％CI 1.892-6.996,P＜0.01)were independent risk factors for intraoperative and 6-months postoperative cerebral ischemic events after stent-assisted coil embolization in patients with intracranial aneurysms.In comparison with the control group,the intensified group has reduced the risk of cerebral ischemic events(OR,0.238,95％CI 0.088-0.646,P=0.005),while there was no statistically significant difference between the conventional dual antiplatelet therapy group and the control group(OR,0.521,95％CI 0.149-1.826,P=0.308).Conclusions This study demonstrates that adjusting the antiplatelet therapy regimens in patients with intracranial aneurysms who did not meet the platelet inhibition rate based on TEG results can significantly reduce the risk of intraoperative and 6-months postoperative cerebral ischemic events.These finding may require validation through further,large-scaled,prospective studies.

Objective:To explore the safety, effectiveness, and short-term outcomes of transoral robotic surgery (TORS) for supraglottic laryngeal cancer.Methods:A retrospective analysis was conducted on patients with supraglottic laryngeal cancer who underwent TORS at Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology, Eye Ear Nose and Throat Hospital of Fudan University, and the First Affiliated Hospital of China Medical University between January 2018 and April 2024. Data on operative time, intraoperative blood loss, postoperative hospital stay, perioperative tracheostomy, nasogastric feeding, complications, and short-term follow-up were analyzed. Statistical analysis was performed using Python.Results:A total of 27 patients with supraglottic laryngeal cancer were included from the four centers, including 24 males and 3 females, with a median age of 66 (65, 68) years [ M( Q1, Q3), same below]. There were 26 cases of squamous cell carcinoma and 1 case of adenoid cystic carcinoma.The TNM staging included T1 in 10 cases (37.04%), T2 in 13 cases (48.15%), and T3 in 4 cases (14.81%); N0 in 14 cases (51.85%), N1 in 7 cases (25.93%), and N2 in 6 cases (22.22%). The Da Vinci Si system was used in 23 cases, and the Da Vinci Xi in 4 cases. The robotic surgical time was 53 (30, 58) min. Concurrent neck dissection was performed in 25 cases, neoadjuvant therapy was given preoperatively in 8 cases (29.63%), and postoperative radiotherapy was administered in 13 cases (48.15%). Tracheostomy was performed in 11 cases (40.74%). Nasogastric tube placement was required in 23 cases (85.19%), with a median duration of 16 (12, 21) days. The postoperative hospital stay was 9.19±4.07 days. The median follow-up time was 12 (3, 30) months. Local recurrence occurred in 2 cases. The 3-year overall survival rate was 100%, and the 3-year disease-free survival rate was 94.1%. Conclusion:With appropriate patient selection, TORS for supraglottic laryngeal cancer demonstrates satisfactory short-term outcomes, thereby offering advantages in safety, efficacy, and minimal invasiveness, which can be considered a new treatment option for this condition.

Objective To investigate the value of adjusting antiplatelet treatment regimens guided by thromboelastography(TEG)in predicting cerebral ischemic events after stent-assisted embolization of intracranial aneurysms.Methods This study retrospectively and consecutively enrolled patients with intracranial aneurysms who underwent stent-assisted coil embolization admitted to the Department of Neurosurgery of the General Hospital of Eastern Theater Command,from March 2022 to May 2024.Baseline and clinical data of the patients,including gender,age,hypertension,diabetes,dyslipidemia,smoking history,drinking history,and intraoperative use of tirofiban were collected.Antiplatelet therapy(conventional dose aspirin[100 mg once daily]+clopidogrel[75 mg once daily])was initiated immediately after the diagnosis of intracranial aneurysm,and TEG was performed 3 days later.According to the platelet inhibition rate in TEG parameters(platelet inhibition rate induced by arachidonic acid[AA]pathway[AA inhibition rate]or adenosine diphosphate[ADP]pathway[ADP inhibition rate],AA inhibition rate ≥ 50％indicated aspirin effectiveness,AA inhibition rate＜50％indicated aspirin resistance;ADP inhibition rate ≥ 30％indicated clopidogrel effectiveness,ADP inhibition rate＜30％indicated clopidogrel resistance),the patients were divided into the control group(TEG test results met the criteria,i.e.,AA inhibition rate ≥ 50％and ADP inhibition rate ≥ 30％),the conventional dual antiplatelet therapy group(TEG test results did not meet the criteria but were not adjusted for antiplatelet therapy,i.e.,AA inhibition rate＜50％and/or ADP inhibition rate＜30％,but with complex aneurysm morphology[such as irregular shape,daughter sac formation]or high bleeding risk,continuing conventional dual antiplatelet therapy),and the intensified group(TEG test results did not meet the criteria and the antiplatelet therapy regimen was adjusted,i.e.,AA inhibition rate＜50％and/or ADP inhibition rate＜30％,adjusting the antiplatelet therapy regimen).All patients underwent stent-assisted coil embolization after TEG testing.From 0 to 3 months after the operation,all three groups maintained the above antiplatelet therapy.At 3 months after the operation,routine head MRI,CT and other examinations were performed.If no cerebral ischemic events occurred and the imaging results were satisfactory(good stent position,no aneurysm occlusion residual or slight residual at the neck[neck width of the aneurysm 2mm]),the treatment could be adjusted to single antiplatelet therapy(aspirin 100 mg once daily).If a patient experienced a cerebral ischemic event during the follow-up period,regardless of the stage after the operation,dual antiplatelet therapy(aspirin[100mg once daily]+clopidogrel[75 mg once daily])was immediately restarted or maintained and continued for at least 6 months.The primary endpoint was intraoperative and 6-months postoperative cerebral ischemic events(including DSA-confirmed intraoperative acute thrombosis and infarction foci confirmed by head CT or MRI).Baseline and clinical data of the three groups were compared.All patients were divided into groups with ischemic stroke event and without according to the primary endpoint,univariate Logistic regression analysis was then performed on both groups.Variables with P＜0.1 in the univariate Logistic regression analysis were included in the multivariate Logistic regression analysis to explore the influencing factors of cerebral ischemic events after stent-assisted coil embolization for intracranial aneurysms.Results A total of 499 patients were included,including 178 males and 321 females,with a median age of 59(53,68)years.Among them,there were 341 patients in the control group,42 in the conventional dual antiplatelet therapy group,and 116 in the intensified group.There were 47 cases of cerebral ischemic events and 452 cases without cerebral ischemic events.There was a statistically significant difference in the intraoperative use rate of tirofiban across the control group,the conventional dual antiplatelet therapy group,and the intensified group(20.2％[69/341]vs.26.2％[11/42]vs.42.2％[49/116],P＜0.01);no statistically significant differences were observed among the three groups in terms of age,gender composition,the proportion of patients with hypertension,diabetes,dyslipidemia,smoking history,drinking history,and the incidence of cerebral ischemic events(all P＞0.05).The results of multivariate Logistic regression analysis showed that hypertension(OR,2.924,95％CI 1.416-6.037,P=0.004)and intraoperative use of tirofiban(OR,3.638,95％CI 1.892-6.996,P＜0.01)were independent risk factors for intraoperative and 6-months postoperative cerebral ischemic events after stent-assisted coil embolization in patients with intracranial aneurysms.In comparison with the control group,the intensified group has reduced the risk of cerebral ischemic events(OR,0.238,95％CI 0.088-0.646,P=0.005),while there was no statistically significant difference between the conventional dual antiplatelet therapy group and the control group(OR,0.521,95％CI 0.149-1.826,P=0.308).Conclusions This study demonstrates that adjusting the antiplatelet therapy regimens in patients with intracranial aneurysms who did not meet the platelet inhibition rate based on TEG results can significantly reduce the risk of intraoperative and 6-months postoperative cerebral ischemic events.These finding may require validation through further,large-scaled,prospective studies.

Objective:To compare the efficacy of gasless robotic surgery via transaxillary approach and combined axillary-retroauricular approach for unilateral N1b PTC, and to explore the safety and effectiveness of gasless robotic surgery via transaxillary approach for unilateral N1b PTC. Methods:Unilateral N1b PTC patients who underwent surgery in the Department of Otolaryngology, Sun Yat Sen Memorial Hospital, Sun Yat sen University between July 2016 and December 2024 were included and analyzed. According to the inclusion and exclusion criteria and the differences of surgical approaches, the patients were divided into the transaxillary approach（TA） group and the combined axillary-retroauricular approach（TARA） group. The demographic data, operation time, intraoperative blood loss, postoperative drainage volume, postoperative complications, shoulder function evaluation, postoperative visual analogue scale（VAS） of neck aesthetics and recurrence of the two groups were statistically analyzed. Results:A total of 88 patients undergoing gasless robotic surgery were included in this study, including 23 cases in the TA group and 65 cases in the TARA group. The proportion of males in the TA group was significantly higher than that in the TARA group（56.5% vs 21.5%, χ²=9.776, P=0.002）. The total operation time in the TA group was significantly lower than that in the TARA Group（180.00[155.00, 220.00]min vs 220.00[177.50, 272.50]min, z=-2.775, P=0.006）, and the postoperative blood loss in the TA group was significantly lower than that in the TARA Group（30.00[20.00, 50.00]ml vs 50.00[30.00, 60.00]ml, Z=-2.127, P=0.033）. The proportion of area Ⅱ-Ⅴ in the TA group and the TARA group was 87.0% and 70.8%, respectively, and there was no significant difference between the two groups（P>0.05）. There was no significant difference in lateral cervical lymph node dissection and central lymph node dissection between the two groups（P>0.05）. During the follow-up period, no recurrence was found in the two groups, and there was no significant difference in the incidence of complications between the two groups（P>0.05）. According to the stratification of dynamic recurrence risk assessment, it can be seen that the proportion of curative effect satisfaction in the TA group was as high as 95.7%, and that in the TARA group was as high as 81.5%, with no significant difference between the two groups. There was no significant difference in VAS score of neck, Constant Shoulder Score and NDⅡ scale between the two groups（P>0.05）. Conclusion:Gasless robotic surgery via transaxillary approach for unilateral N1b PTC is safe and feasible, and the amount postoperative lymph node acquisition is equivalent to that of combined axillary-retroauricular approach, which can provide a new choice for the treatment of unilateral N1b PTC patients.
Humans ; Robotic Surgical Procedures/methods* ; Axilla/surgery* ; Male ; Female ; Operative Time ; Middle Aged ; Adult ; Treatment Outcome ; Postoperative Complications

Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.

Objective:To explore the clinical efficacy, safety and possible neuroimaging mechanism of deep transcranial magnetic stimulation (dTMS) and repetitive transcranial magnetic stimulation (rTMS) in the treatment of refractory migraine.Methods:Thirty patients with refractory migraine were selected from the Department of Neurology, Affiliated Hospital of North Sichuan Medical College from October 2022 to August 2023. The patients were randomly divided into dTMS group ( n=10), rTMS group ( n=10) and sham stimulation group ( n=10). The dTMS group was treated with H7 coil and the rTMS group with "8" coil, and the sham stimulation group was treated with sham stimulation rTMS with the frequency of 10 Hz. The stimulation site was the contralateral primary motor cortex (M1) of headache, which was treated for 2 weeks (3 600 pulses per time, 5 times per week, 10 times in total). Visual Analogue Scale (VAS) and Headache Impact Test-6 (HIT-6) evaluations were performed before treatment, on the first day after treatment, and 1, 3 and 6 months after treatment. The resting-state functional magnetic resonance images of the 3 groups of patients before and after treatment were collected and analyzed by MATLAB2018b, SPM12 and RESTPLUS softwares, and the brain regions with different regional homogeneity (ReHo) before and after treatment were obtained. The general clinical data and scale scoring data were analyzed and processed by SPSS 26.0 version software. Results:There were significant differences in VAS scores among the dTMS group (before treatment 6.70±0.68, the first day after treatment 5.60±0.70, 1 month after treatment 5.00±0.82, 3 months after treatment 3.50±0.85, 6 months after treatment 3.90±1.45), the rTMS group (before treatment 6.90±0.74, the first day after treatment 5.90±0.74, 1 month after treatment 5.30±0.82, 3 months after treatment 5.30±0.82, 6 months after treatment 6.80±0.63) and the sham stimulation group (before treatment 6.60±0.97, the first day after treatment 6.70±0.95, 1 month after treatment 6.90±1.10, 3 months after treatment 6.70±0.68, 6 months after treatment 7.10±0.88; F=16.054, P<0.001), VAS scores among different time points ( F=34.292, P<0.001), and the interaction between groups and time ( F=24.136, P<0.001). Compared with those before treatment, VAS scores in the dTMS group and the rTMS group decreased on the first day after treatment, 1 month and 3 months after treatment (all P<0.05); VAS scores decreased in the dTMS group 6 months after treatment ( P<0.05). Compared with the sham stimulation group, the VAS scores of the dTMS group were lower at the same time points after treatment (all P<0.05), and the VAS scores of the rTMS group were lower on the first day after treatment, 1 month and 3 months after treatment (all P<0.05). Compared with the rTMS group, VAS scores were lower at 3 and 6 months after dTMS treatment (both P<0.05). There were significant differences in HIT-6 scores among groups ( F=13.173, P<0.001), HIT-6 scores among different time points ( F=60.788, P<0.001), and interaction between groups and time ( F=35.576, P<0.001). Compared with those before treatment, the HIT-6 scores in the dTMS group decreased on the first day after treatment ( P<0.05); the HIT-6 scores in the dTMS group and the rTMS group decreased 1 month and 3 months after treatment (both P<0.05); the HIT-6 scores decreased in the dTMS group 6 months after treatment ( P<0.05). Compared with the sham stimulation group, the HIT-6 scores were lower in the dTMS group at the same time points after treatment (all P<0.05), and the HIT-6 scores were lower in the rTMS group at 1 and 3 months after treatment (both P<0.05). Compared with the rTMS group, HIT-6 scores were lower at 3 and 6 months after dTMS treatment (both P<0.05). Analysis of ReHo results: compared with those before treatment, the ReHo values of the right cerebellar angle area 1 increased in the dTMS group and the sham stimulation group, decreased in the rTMS group. The ReHo values of the right middle occipital gyrus, left dorsolateral superior frontal gyrus and right cerebellar area 8 increased in the dTMS group, but decreased in the rTMS group and the sham stimulation group. The ReHo values of the left precentral gyrus and left superior temporal gyrus decreased in the dTMS group, while those in the rTMS group and the sham stimulation group increased. There were no obvious adverse reactions in the 3 groups during the treatment and follow-up period. Conclusions:dTMS and rTMS may help to improve the headache degree and quality of life of patients with refractory migraine, and they are safe, which may be related to the changes of brain network in the right cerebellar angle area 1, right middle occipital gyrus, left dorsolateral superior frontal gyrus, left precentral gyrus, left superior temporal gyrus and right cerebellar area 8.

The clinical characteristics, diagnosis and treatment process of a patient with type Ⅰ sialidosis (ST-1) caused by a homozygous mutation in the NEU1 gene who was missed diagnosis for 5 years were retrospectively analyzed to improve the understanding of the disease. A 16-year-old female patient presented with episodic limb shaking for more than 5 years and single generalised tonic-clonic seizure. Electroencephalogram (EEG) tests conducted at external hospital did not show any abnormalities, and head magnetic resonance imaging (MRI) showed general normality. Multiple antiepileptic drugs could not control the attack and the symptoms gradually worsened. After admission, the patient was found to have symptoms of easy wrestling and decreased vision, as well as signs of nystagmus and ataxia. The reexamination of the EEG showed extensive spike-and-slow complexes, and the brain MRI showed cerebellar atrophy. Furthermore, the whole-exome gene testing revealed the c.544A>G homozygous mutation in the NEU1 gene, leading to the diagnosis of ST-1. Levetiracetam tablets and clonazepam were given to improve the patient′s symptoms. During the follow-up, sleep improved compared to before, and myoclonus was significantly reduced. Therefore, patients with recurrent myoclonus, ataxia, and visual impairment without cognitive impairment should be aware of the possibility of sialidosis. Genetic testing plays an important role in the diagnosis of sialidosis.

Background The impact of cold spells on population health can be categorized into an independent main effect of extreme low temperatures and an added effect of prolonged low temperatures. However, studies on the added effects of cold spells on hospitalizations remain limited. Objective To investigate the added effects of cold spells on hospitalizations of residents in Hengyang City, Hunan Province, and to provide a scientific basis for establishing a cold spell early warning system. Methods Daily meteorological data, air pollutant data, and hospitalization data from six tertiary hospitals of four districts in Hengyang City from 2017 to 2023 were collected. A generalized linear model (GLM) combined with a distributed lag nonlinear model (DLNM) was used to assess the added effects of cold spells on non-accidental hospitalizations, as well as hospitalizations for circulatory system diseases and respiratory system diseases, after controlling the main effect of temperature. The modifying effects of cold spell characteristics (intensity and duration) and individual characteristics (gender and age) were also analyzed. Results Compared with non-cold spell periods, the relative risks (RRs) of total non-accidental hospitalizations and hospitalizations across disease categories, genders, and age groups were elevated during cold spells of varying intensities and durations. However, the total effects of cold spells exhibited a "U-shape" nonlinear relationship with intensity and decreased with prolonged duration. During high-intensity cold spells (daily average temperature < P₅ and lasting ≥ 2 d), the RR (95%CI) for non-accidental hospitalizations was 1.71 (1.21, 2.42); the RRs (95%CIs) for males and females were 1.99 (1.38, 2.84) and 1.47 (1.00, 2.16), respectively; for individuals < 65 years and ≥ 65 years, the RRs (95%CIs) were 1.59 (1.12, 2.26) and 1.93 (1.27, 2.92), respectively; and for circulatory and respiratory system diseases, the RRs (95%CIs) were 1.84 (1.22, 2.79) and 1.07 (0.71, 1.60), respectively. No statistically significant differences were observed between the above subgroups. The single-day lagged effects of cold spells displayed a two-peaked pattern. The single-day lag RR for total non-accidental hospitalizations peaked at lag 1 d after cold spell exposure, declined thereafter, and began to rise again after lag 5 d, reaching a second peak at lag 12–13 d before gradually decreasing. The lagged effects remained statistically significant during lag 8–18 d. The lag patterns of cold spell associations across disease categories, genders, and age groups were largely consistent with those of total hospitalizations. Conclusion Cold spells have a significant impact on non-accidental hospitalizations of residents in Hengyang City, with notable lagged effects. The findings provide important theoretical support for establishing a more targeted cold spell early warning system.

Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.