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 analyze the epidemiological characteristics of dengue fever outbreaks in schools from Guangzhou in 2024, so as to provide a reference for formulating targeted prevention and control policies and measures. Methods: By using the National Infectious Disease Surveillance Information Reporting Management System to obtain information on dengue fever cases in Guangzhou from January 1st to December 31st, 2024. Descriptive data analysis was conducted on the temporal distribution, regional distribution, and school distribution of dengue fever outbreaks in schools. A mediation effect model was used to analyze the mediating effect of the time between onset and reporting between the type of school and the occurrence of recurrent cases. Results: In 2024,12.41% (385 cases) of dengue fever cases in Guangzhou involved schools, with 300 schools affected. Among these, 16 schools (5.33%) reported cluster outbreaks, and 24 schools (8.00%) reported secondary cases. The first dengue case at the school was reported at 26 July and the last case was reported at 4 December, the peak reporting period for cases was October 7 to November 3. The incidence of secondary cases in schools in central urban areas (5.19%) was lower than that in suburban schools ( 17.39 %), and the difference was statistically significant ( χ 2=9.15, P <0.01). The time from onset to reporting partially mediated the relationship between school type and the occurrence of recurrent cases ( β=0.23, P <0.05), accounting for 21.50% of the total effect. Conclusions Dengue fever is a key infectious disease facing schools in Guangzhou during summer and autumn. Surveillance of dengue fever outbreaks in schools should be strengthened during the peak season to reduce the risk of cluster outbreaks and the occurrence of secondary cases.

Purpose To observe the clinical and CT features of severe immune checkpoint inhibitor-related pneumonitis(CIP)in lung cancer patients.Materials and Methods A total of 174 patients with lung cancer who received immune checkpoint inhibitor(PD-1/PD-L1 inhibitors)in Xi'an International Medical Center Hospital from September 1,2019 to March 31,2022 were retrospectively collected.Clinical and imaging features of patients with severe CIP were analyzed.Results There were 23 patients who met the diagnostic criteria of severe CIP.Among them,22 were male patients,15 were younger(＜65 years old),17 had a history of underlying lung disease,16 had a history of chemoradiotherapy and other treatments,and 21 had a history of combined radiotherapy and chemoradiotherapy.The median time from the initiation of immune checkpoint inhibitor to CIP was 128(74,348)days.19 patients were non-small cell carcinoma.CIP occurred in 16 patients with right lung cancer,15 had tumor central airway invasion,14 had radiographic features of diffuse alveolar injury/acute interstitial pneumonia pattern,and 20 died during follow-up.Conclusion Severe CIP is likely to occur in male lung cancer patients with a history of basic medical history and radiotherapy and chemotherapy.The clinical manifestations are varied,and the main imaging features are diffuse alveolar injury/acute interstitial pneumonia pattern,and the prognosis is poor.

Objective:To compare the efficacy and safety of ultrasound-guided microwave ablation(MWA) and radiofrequency ablation (RFA) in the treatment of benign thyroid nodules.Methods:The clinical data of 119 patients (187 nodules in total) with benign thyroid nodules who were treated with ultrasond-guided MWA (56 cases) and RFA (63 cases) in Shenzhen Third People′s Hospital from January 2018 to January 2020 were retrospectively analyzed. The ablation time, ablation time per unit volume, volume reduction rate of thyroid nodules after treatment, changes in thyroid function before and after treatment, and incidence of complications were compared between the two groups.Results:The ablation time and ablation time per unit volume in the MWA group were significantly shorter than those in the RFA group (all P<0.05). At 3, 6, and 12 months after treatment, the reduction rate of nodule volume in MWA group was higher than that in RFA group, and the difference was statistically significant in the subgroup with nodule >10 ml (all P<0.05). The incidence of temporary hoarseness in RFA group [6.35%(4/63)]was lower than that in MWA group [12.5%(7/56)], with no statistically significant difference ( P>0.05). Conclusions:Microwave ablation is more effective than radiofrequency ablation in the treatment of large thyroid nodules. Radiofrequency ablation is safer than microwave ablation for thyroid nodules near the risk triangle, but further research is needed to confirm.

Objective:To investigate the diagnostic value of MRI in benign and malignant breast lesions with cluster ring enhancement.Methods:The imaging signs of 68 patients with clustered ring enhancement who underwent MRI examination due to clinical palpation, ultrasound or X-ray examination for suspected malignant lesions in Tangdu Hospital of Air Force Military Medical University from October 2017 to July 2019 were retrospectively analyzed. The differences between benign and malignant lesions in the distribution pattern, T2 lipid suppression signal intensity, time-signal intensity curve (TIC), ductal dilatation, peripheral gland edema, pectoralis major edema were compared using χ2 test or Mann-Whitney U test, and the risk factors of MRI imaging signs of malignant breast lesions were analyzed using binomial logistic regression model. Results:There were 68 cluster ring enhancement lesions in 68 patients, all of which were single lesions, among which 18 cases (26.5%) were benign, and the common lesions were plasma cell mastitis (9 cases). Fifty cases (73.5%) were malignant, and the most common type was invasive breast cancer (40 cases). Imaging features of plasma cell mastitis showed cluster ring enhancement, regional distribution, slightly high signal on fat suppression T2 image, type Ⅲ TIC, with ductal dilatation, edema of peripheral glands and pectoralis major. Imaging features of invasive breast cancer showed cluster ring enhancement, regional distribution, iso-signal on fat suppression T2 image, type Ⅲ TIC, no ductal dilatation, and edema of peripheral gland and pectoralis major. There were statistically significant differences in the intensity of fat-suppression T2 signal ( Z=3.003, P=0.003) and duct dilatation ( χ2=7.174, P=0.007) between benign and malignant lesions. There were no significant differences in distribution ( χ2=5.510, P=0.313), TIC type ( χ2=3.538, P=0.133), peripheral gland edema ( χ2=0.164, P=0.686) and pectoralis major edema ( χ2<0.001, P>0.999). The analysis of binomial logistic regression model showed that fat-suppression T2 iso-signal ( OR=0.182, 95% CI: 0.036-0.914, P=0.039) and no ductal dilatation ( OR=0.198, 95% CI: 0.047-0.846, P=0.029) were the risk factors for breast malignant lesions. Conclusion:Breast cancer MRI findings of cluster ring enhancement, fat-suppression T2 iso-signal and no ductal dilatation are related risk factors for malignant breast lesions. MRI is helpful for early detection and diagnosis of breast lesions.

Objective To explore the teaching effects of Lecture Based Learning (LBL) incorporated with Case Based Learning (CBL) and Problem Based Learning (PBL) methods in the teach-ing of anatomy.Methods 740 students of Grades 2012 and 2013 from clinical medical major were chosen as the subjects,randomly divided into experimental and control groups.LBL was conducted in the control group of 644 students,while LBL+PBL+CBL method was applied in the experimental group of 96 students.After completion of the course,all students were surveyed with the questionnaire and tested with specimen and theoretical examinations.The data was collected and analyzed with SPSS 17.0 and two sample U tests.Results The students' time of learning anatomy in the control group outside classroom teaching was (105 ± 25) minutes per week,while the students' time of learning anatomy in the experimental group was (190 ± 25) minutes per week.The difference was statistically significant (t=31.08,P=0.000).The difference of after-class total learn-ing time was also statistically significant between two groups(t=27.42,P=0.000).Percentages of satisfaction with teaching methods for control group were 87.5％ and 87％,while for the experimental group 98％ and 100％.Kruskal-Wallis test showed there were significant differences in experimental groups of grades 2012(x2=31.19,P=0.000) and 2013 (x2=40.35,P=0.000) compared with control group.Comparison of both groups' results of the examinations was statistically significant concerning multiple choices,essays and case analysis questions (P＜0.05).Conclusion Teaching method of LBL incorporated with PBL and CBL was significantly effective than that of the sole traditional LBL method,which indicated its practice value.

Objective To investigate the expression and clinical significance of CXCR3/CXCL10in human cancer.Methods CXCR3 and CXCL10 were detected in 60 paraffinic tissues of patients with primary breast cancer,20 of mammary fibroma and 20 of mastopathy by immunohistochemistry S-P method and two stage method.Results The expression of CXCR3 (40/60,66.7％ ) and CXCL10 (45/60,75％)in breast cancer was higher than that in mastopathy [CXCR3(8/20,40％ )x2 =4.44,P =0.035 ;CXCL10( 10/20,50％ )x2 =4.36,P =0.037)].The expression of CXCR3 was related to status of axillary lymph node metastasis,clinical stage and the expression of HER-2 (x2 =4.15,P =0.042; x2 =7.74,P =0.021 ;x2 =4.27,P =0.039).The expression of CXCR3 had positive relationship to the number axillary lymph node metastasis( rs =0.375,P =0.003 ),clinical stage ( rs =0.451,P =0.000).Conclusions CXCR3 may be related to the progression and metastasis of breast cancer,and it may be used as a marker of breast cancer prognosis.

BACKGROUND: Neonatal rat liver cells are moderately differentiated cells with the characterization and function of both liver progenitors and hepatocytes, thus, it is an ideal cell source for the study of the hepatocyte characterization. OBJECTIVE: To explore the isolation and in vitro culture of neonatal rat liver cells.DESIGN, TIME AND SETTING: An in vitro cytology trial was carried out at the Institute of General Surgery, General Hospital of Chinese PLA from March to August 2008.MATERIALS: Neonatal SD rats with 3 months old were used, irrespective of genders.METHODS: Liver cells from neonatal rat were isolated by tissue piece-cold trypsin digestion combining with multi-step low centrifuge, and cultured onto the plate in HepatoZYME-SFM supplemented with 10% fetal serum. The growth and function of the cultured liver cells was evaluated by contrast microscopy, MTT assay, PAS staining and urine enzyme test. MAIN OUTCOME MEASURES: Cell morphology and viability, content of glycogen, as well as urea level in the supernatant.RESULTS: Totally 1.0×10~6-2×10~6 cells per whole liver could be obtained with viability above 90%. The cells displayed round or orbicular-ovate shapes with big nuclei, and cell body was smaller than mature cells. More than 95% purity achieved after removal erythrocyte, nonparenchymal cells and dead cells with multi-step low-speed centrifugalization. The viability of cells were gradually increased at the beginning of culture, noticeably alleviated at the 3 days, and reached a peak at the 11 days, and then gradually decreased. The difference between day 1 and days 11, as well as days 15 and days 11 had significance (P=0). Liver cells cultured in HepatoZYME-SFM attached and kept hepatocyte-specific morphology. PAS staining showed the cultured liver cells at day 7 were strongly positive and then the positive cells decreased gradually, until 15 days, only few positive cells could be seen. Urea level in the supernatant remained stable at the initial time and dramatically decreased after 7-day culture. CONCLUSION: The tissue piece-cold trypsin digestion and HepatoZYME-SFM is a simple and efficient isolation and culture system for neonatal rat liver cells.

Obiective To set up a method of scaffold evaluation using human cell line as seed cells and screen appropriate scaffold for live tissue engineering, Methods HepG2 cells were plated onto biodegradable polymer scaffolds: PLGA, 3% chitosan (3%CS) and 2% silk fibroin (2%SF), and cultured in vitro. The growth, distribution and function of HepG2 cells in the scaffolds were evaluated using MTT assay, H.E. staining, and urea assay kit. Results HepG2 cells plated on the three scaffolds maintained a proliferative state. In contrast, the cells on the 2%SF proliferated strongly, while the cells on the PLGA and chitin proliferated poorly. Histological examination showed that HepG2 cells distributed evenly on the 2%SF scaffold with a high amount, while few cells could be found on the PLGA and ehitin at day 7. Cell function assay showed that HepG2 cells on the 2%SF and PLGA exhibited slower decrease of urea synthesis compared to HepG2 cells on the chitosan. Conclusion The three scaffolds have good biocompatibility. In contrast, 2%SF scaffold is more appropriate for liver tissue engineering. This method may be used for scale screening of scaffolds for liver tissue engineering.