[Analysis on the infection source of the first local cluster epidemic caused by the VOC/Gamma variant of SARS-CoV-2 in China]

Objective: To investigate a SARS-CoV-2 epidemic reported in Rongcheng City, Weihai, Shandong Province. Methods: The SARS-CoV-2 nucleic acid positive patients and their close contacts were investigated, and the whole genome sequencing and genetic evolution analysis of 9 variant viruses were carried out. An infection source investigation and analysis were carried out from two sources of home and abroad, and three aspects of human, material and environment. Results: A total of 15 asymptomatic infections were reported in this epidemic, including 13 cases as employees of workshop of aquatic products processing company, with an infection rate of 21.67% (13/60). Two cases were infected people's neighbors in the same village (conjugal relation). The first six positive persons were processing workers engaged in the first process of removing squid viscera in the workshop of the company. The nucleic acid Ct value of the first time were concentrated between 15 and 29, suggesting that the virus load was high, which was suspected to be caused by one-time homologous exposure. The whole genome sequence of 9 SARS-CoV-2 strains was highly homologous, belonging to VOC/Gamma (Lineage P.1.15). No highly homologous sequences were found from previous native and imported cases in China. It was highly homologous with the six virus sequences sampled from May 5 to 26, 2021 uploaded by Chile. The infection source investigation showed that the company had used the squid raw materials captured in the ocean near Chile and Argentina from May to June 2021 over the last 14 days. Many samples of raw materials, products and their outer packages in the inventory were tested positive for nucleic acid. Conclusion: This epidemic is the first local epidemic caused by the VOC/Gamma of SARS-CoV-2 in China. It is speculated that the VOC/Gamma, which was prevalent in South America from May to June 2021, could be imported into China through frozen squid.

Body mass index increases the recurrence risk of breast cancer: a dose-response meta-analysis from 21 prospective cohort studies

OBJECTIVE

The purpose of this study was to investigate the effect of body mass index (BMI) on the recurrence risk of breast cancer.

STUDY DESIGN

Dose-response meta-analysis.

METHODS

Cohort studies that included BMI and the recurrence of breast cancer were selected through various databases including PubMed, Web of Science, the China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals (VIP), and Wanfang Data Knowledge Service Platform (WanFang) until November 30, 2021. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of literature. A two-stage random-effects meta-analysis was performed to assess the dose-response relationship between BMI and breast cancer recurrence risk. Heterogeneity between studies is assessed using I².

RESULTS

The relative risk (RR) of BMI <25 kg/m² vs BMI ≥25 kg/m², BMI <30 kg/m² vs BMI ≥30 kg/m² were 1.09 (95% CI: 1.00-1.19) and 1.15 (95% CI: 1.04-1.27), suggesting that BMI had a significant effect on the recurrence risk of breast cancer, and there might be a dose-response relationship between them. A total of 21 studies were included in dose-response meta-analysis, which showed that there was a positive linear correlation between BMI and the risk of recurrence (RR = 1.02, 95% CI: 1.01-1.03). For every 1 kg/m² increment of BMI, the risk of recurrence increased by approximately 2%. In subgroup analyses, positive linear dose-response relationships between BMI and recurrence risk were observed among Asian and study period >10 years groups. For every 1 kg/m² increment of BMI, the risk of recurrence increased by 3.41% and 1.87%, respectively.

CONCLUSIONS

The recurrence risk of breast cancer increases with BMI, which is most obvious among Asian women.

[Study of development of public health safety literacy scale in China]

Objective: To develop a suitable scale for assessing the public health safety literacy in residents in China. Methods: The initial scale of Chinese public health safety literacy was developed through theoretical conceptualization, item pooling, field verifying and item inclusion and exclusion. Then the initial scale was converted into an electronic questionnaire. A total of 2 809 residents from 4 provinces were randomly selected for field testing. Classical test theory (CTT) and item response theory (IRT) were used for item reduction. SPSS 23.0 was used for exploratory factor analysis (EFA) and unidimensional testing. Package R 4.1.1 ltm and mirt were used for the analysis of the psychometric properties of items and generate the ICC, IIC and TIF. Results: The initial scale had 30 items (B1-B30), and the test took 9.8 s to complete one item averagely. According to the CTT, B2 was deleted due to coefficient of total correlation (CITC) <0.3 and the item-dimension correlation coefficient (IDCC) <0.4. B23 was deleted due to CITC<0.3, IDCC<0.4 and difficulty index (W) <0.2. B30 was deleted due to CITC<0.3 and W<0.2. The total Cronbach's α of the scale was 0.923 after deletion. EFA indicated that 14 items should be deleted due to lower factor loadings <0.7. EFA was conducted for remaining 13 items and 2 common factors were extracted, the factor loadings of all items were >0.7, the accumulated variance contribution of the 2 common factors was 63.361%, and the total Cronbach's α was 0.891, showing unidimensionality, IRT was used to test the remaining items. B14 and B20 were deleted due to discrimination coefficient (a) <0.3, difficulty threshold coefficient (b) ∉[-3,3], the small amount of information and the flat, crowded, non-monotonic ICC, and IIC. Finally, the Cronbach's α of the 11-itemed scale was 0.936 with TLI=0.97, CFI=0.99, and RMSEA=0.03. Conclusion: The final scale has good reliability, validity, discrimination, difficulty level and feasibility, and can be applied for the rapid assessment of public health safety literacy in China.

[Management of the internal carotid artery during lateral skull base surgery: a series of 41 cases]

Objective: To introduce our experience on dealing with the internal carotid artery (ICA) during the resection of lateral skull base tumors, and to explore the reference values for using radiological findings to make a rational surgical plan. Methods: A retrospective study of patients who underwent resection of lateral skull base tumors involving ICA at Peking Union Medical College Hospital from May 2015 to May 2021 was conducted. The demographic information, preoperative examinations, diagnosis, surgical details and follow-ups were collected. A total of 41 patients were enrolled [24 (58.5%] females, 17 (41.5%) males], with an average age of 47.9 years. According to the preoperative imaging findings, the relationships between the tumors and ICA were divided into four types: adjacency, compression, invasion and ICA aneurysm. Results: The ICA was preserved in 32 (78.0%, 32/41) cases and was reconstructed in nine (22.0%, 9/41) cases. All the 27 (65.9%, 27/41) tumors adjacent to ICA were successfully separated from the artery. Among the 11 tumors compressing the ICA, six were resected with the involved ICA segment and vascular reconstruction was conducted. One (2.4%, 1/41) tumor invading ICA and two (4.9%, 2/41) ICA aneurysms required revascularization. The mean follow-up time was (26.1±2.9) months. There was no recurrence, except one case of adenoid cystic carcinoma which had brain metastases one year after surgery. Conclusions: According to the preoperative imaging, lateral skull base tumors adjacent to ICA can be detached from the vascular surface. Separation should be attempted first for tumors compressing ICA, and revascularization should be followed if separation failed. Vascular reconstruction is usually needed in the removal of tumors invading ICA and ICA aneurysms. Preoperative radiology can provide good references for planning a surgery for lateral skull base tumors.

[Berberine inhibits erastin-induced ferroptosis of mouse hippocampal neuronal cells possibly by activating the Nrf2-HO-1/GPX4 pathway]

OBJECTIVE

To explore the mechanism by which berberine inhibits ferroptosis of mouse hippocampal neuronal cells (HT22).

METHODS

Cultured HT22 cells were pretreated with 30 or 60 μmol/L berberine for 2 h before exposure to 0.5 μmol/L erastin for 8 h, and the cell proliferation, intracellular ferric iron level, changes in intracellular reactive oxygen species (ROS) and cell apoptosis were detected using CCK-8, Fe²⁺ fluorescent probe, fluorescent dye (DAPI) and fluorescent probe (H2DCFH-DA). RT-qPCR and Western blotting were used to detect the mRNA and protein expressions of Nrf2, HO-1 and GPX4 in the cells. We further tested the effects of treatments with 2 μmol/L ML385 (a Nrf2 inhibitor), 60 μmol/L berberine and erastin in the cells to explore the protective mechanism of berberine against erastin-induced ferroptosis in the neuronal cells.

RESULTS

Treatment with 0.5 μmol/L erastin significantly lowered the viability of HT22 cells (P < 0.05) and increased the production of ROS, cell apoptosis rate and ferric iron level (P < 0.05). Pretreatment with 30 and 60 μmol/L berberine both significantly increased the vitality of erastin-exposed cells (P < 0.05) and lowered the levels of intracellular ROS and ferric iron content (P < 0.05). RT-qPCR and Western blotting showed that berberine obviously promoted the expressions of Nrf2, HO-1 and GPX4 in the cells (P < 0.05), and treatment with ML385 significantly inhibited the Nrf2-HO-1/GPX4 pathway, increased intracellular ROS and ferric iron contents and mitigated the protective effect of berberine against erastin-induced ferroptosis (P < 0.05).

CONCLUSION

Berberine can inhibit erastin-induced ferroptosis in HT22 cells possibly by activating the Nrf2-HO-1/ GPX4 pathway.

The Safety and Efficacy of Flow Diversion versus Conventional Endovascular Treatment for Intracranial Aneurysms: A Meta-analysis of Real-world Cohort Studies from the Past 10 Years

BACKGROUND

Although the flow diverter has advantages in the treatment of intracranial aneurysms, pooled studies that directly compare it with conventional endovascular treatments are rare.

PURPOSE

Our aim was to compare the safety and efficacy of flow-diverter and conventional endovascular treatments in intracranial aneurysms.

DATA SOURCES

We performed a comprehensive search of the literature using PubMed, EMBASE, and the Cochrane Database.

STUDY SELECTION

We included only studies that directly compared the angiographic and clinical outcomes of flow-diverter and conventional endovascular treatments.

DATA ANALYSIS

Random effects or fixed effects meta-analysis was used to pool the cumulative rate of short- and long-term angiographic and clinical outcomes.

DATA SYNTHESIS

Eighteen studies with 1001 patients with flow diverters and 1133 patients with conventional endovascular treatments were included; 1015 and 1201 aneurysm procedures were performed, respectively. The flow-diverter group had aneurysms of a larger size (standard mean difference, 0.22; 95% CI, 0.03-0.41; P = .026). There was a higher risk of complications in the flow-diverter group compared with the conventional endovascular group (OR, 1.4; 95% CI, 1.01-1.96; P = .045) during procedures. The follow-up angiographic results of flow-diverter treatment indicated a higher rate of complete occlusion (OR, 2.55; 95% CI, 1.70-3.83; P < .001) and lower rates of recurrence (OR, 0.24; 95% CI, 0.12-0.46; P < .001) and retreatment (OR, 0.31; 95% CI, 0.21-0.47; P < .001).

LIMITATIONS

Limitations include a retrospective, observational design in some studies, high heterogeneity, and selection bias.

CONCLUSIONS

Compared with the conventional endovascular treatments, the placement of a flow diverter may lead to more procedure-related complications, but there is no difference in safety, and it is more effective in the long term.

[Etiology, diagnosis and treatment of infraoccluded primary second molars]

Infraocclusion is a phenomenon that the relative occlusal growth of a tooth stops after the period of active eruption and then the tooth becomes depressed below the occlusal plane. Infraocclusion occurred more commonly in children and the mostly affected teeth were the primary mandibular second molars. The occlusal problem caused by infraocclusion may progressively worsen with age. This review summarizes the etiology, diagnosis and treatment of infraoccluded second primary molars, so as to provide reference for the dental clinicians.

[Analysis of the efficacy and safety of low-dose aspirin in preventing renal artery stenosis in kidney transplantation]

Objective: To evaluate the clinical value of aspirin as a prophylactic for transplant renal artery stenosis (TRAS). Methods: From January 2017 to November 2019, clinical data of 307 patients who had undergone renal transplant in Zhengzhou University People's Hospital were collected. Patients were divided into two groups: the treatment group (124 recipients who had taken oral aspirin 100 mg/d after transplant) and the control group (183 recipients who had not taken aspirin after transplant). The general data, incidence of initially diagnosed and confirmed TRAS, type of renal artery anastomosis vessels, duration of stenosis, location of stenosis, and complications were compared between the two groups. The treatment group was further divided into two subgroups, the early group (92 recipients) and the delayed group (32 recipients), according to the time of starting aspirin after operation. Subgroup analysis was performed. Results: Among all 307 patients included, there were 241 males and 66 females, aged 19-64 years. There were no statistical difference between the treatment and control groups in terms of gender, age, comorbidities, number of arterial vessels, type of graft, and acute rejection all P>0.05. Among 46 initially diagnosed TRAS patients, 13 (10.5%) and 33 (18.0%) cases were in the treatment and control group respectively, with no statistically significant difference in stenosis rate (P>0.05). The number of confirmed TRAS patients was 1 (0.8%) and 24 (13.1%) in the treatment and control group respectively, with statistically significant difference in stenosis rate (P<0.001). The proportion of patients with bleeding disorders in the treatment group was slightly higher than that in the control group (13.7% vs 8.7%), and the proportion of infarct diseases was slightly lower than that in the control group (1.6% vs 4.9%). But there was no significant difference in aspirin-related complications between the two groups (P>0.05). Subgroup analysis showed that there was no significant difference in initially diagnosed and confirmed TRAS and aspirin-related complications between the early group and the delayed group (all P>0.05). Conclusions: Oral low-dose aspirin after kidney transplantation can effectively reduce the incidence of TRAS, without increasing the risk of aspirin-related complications.

[Study on the development of public health and safety literacy assessment scale for university freshmen]

Objective: To develop a measurement scale for the public health and safety literacy of university freshmen. Methods: Item pooling was conducted through literature review and in-depth interview with public health experts, and a nominal group was organized to develop the initial items to form the questionnaire. A total of 250 freshmen were randomly selected to complete the questionnaire, and the assessment of psychometric properties were performed to carry out item reduction by using classical test theory and item response theory. Exploratory factor analysis method (EFA) was employed to calculate the item-factor loadings. The data collected from another 318 freshmen were analyzed using confirmatory factor analysis method (CFA). Results: The scale contained 3 dimensions and 9 items with all content validity index ≥0.8. The difficulty coefficient of 9 items was 1.18-2.43. The discriminative validity analysis showed that the difficulty index was 0.41-0.78, and the discrimination index was 0.38-0.64. Each of the remaining items had a statistically significant difference in the score value between the top 27% and lowest 27% of respondents (t>3, P<0.05). The item's Cronbach's α was 0.72-0.77, corrected item-total correlation was 0.33-0.60 and the overall α of the scale was 0.77. EFA indicated all item-factor loading were higher than 0.680, and the accumulated variance contribution of the 3 factors was 62.484%. Results of CFA showed that the overall fitness index of the model reached the fitness standard except for the χ² value. There was no statistical significance in the total score of the scale and the scores of each item among groups with different demographic characteristics (P>0.05). Conclusions: The newly developed public health safety literacy scale had a good reliability,validity,stability and item constancy.It can be used in measurement of the public health and safety literacy of university freshmen.

[Effects of eye exercises on axial eye elongation in junior students]

Objective: To evaluate the association between the eye exercises and one-year axial eye elongation in grade 7 students in Beijing. Methods: Sampling was performed using a multistage random cluster approach, and 1 443 students of grade 7 were selected from 9 middle schools in 6 districts for the baseline survey. Data were collected by questionnaires and axial length measurement. Multiple linear regression analysis was used to evaluate the association between eye exercises and excessive axial eye elongation. Results: Among 1 197 (82.95%) students with complete information, the median (Q_R) age was 12.00 (1.00) years old, girls accounted for 44.28%, and the median (Q_R) axial eye elongation was 0.22 (0.18) mm. In the multiple linear regression analysis, the frequency of eye exercises was significantly correlated with excessive axial eye elongation in boys (β=-0.135, 95%CI:-0.253--0.018) but not in girls (β=-0.075, 95%CI:-0.207- 0.058) after adjusting for sex, age, body height, the number of myopic parents, time spent outdoors and time spent on reading and writing outside class; while the seriousness of eye exercises was not significantly associated with axial eye elongation in boys (β=-0.028, 95%CI: -0.114-0.058) and girls (β=-0.035, 95%CI: -0.134-0.064). Conclusion: The increased frequency of eye exercises is beneficial to control the axial eye elongation in boys in Beijing.

[Clinicopathological features of malignant mixed mesodermal tumor: analysis of 50 cases]

Objective: To investigate the clinicpathological, immunohistochemical and molecular genetic features of malignant mixed mesodermal tumor (MMMT) in the female reproductive system. Methods: To analyze its histopathological characteristics, we performed a retrospective review of the MMMT cases diagnosed at PLA General Hospital, Beijing, China during 2005-2019 using its surgical and pathological databases. EnVision immunohistochemical staining was used to detect the expression of ER, PR, p16, p53 and MMR proteins. Results: Fifty cases were conformed to the diagnosis, including 29 cases originated in the uterus, 16 cases in ovary, 4 cases of synchronous occurrence in uterus and ovary, 1 case in cervix. The tumor was histologically composed of two components, namely carcinoma and sarcoma ones, with clear borderline or blend mutually. The proportion of cancer component in the whole tumor ranged from 5%-90%. The proportion of carcinoma was more than 50% in 76% of the cases, and less than 50% in 24% of cases, including 2 cases with<10% of carcinoma. In the cases of primary uterine MMMT, the main carcinoma type was high grade endometrioid carcinoma (55%, 16/29). In ovarian MMMT, the main carcinoma type was serous carcinoma (12/16), while that of cervical MMMT was squamous cell carcinoma. The others were clear cell carcinoma or the undifferentiated carcinoma. There was one carcinoma type in most cases, only 7 cases had two carcinoma types. Homologous sarcomas, including stromal sarcoma, leiomyosarcoma and high-grade spindle cell sarcomas, were more commonly found in uterine MMMT (72.4%, 21/29). While heterogenic sarcomas, including chondrosarcoma, osteosarcoma and rhabdomyosarcoma, were more commonly noted in ovarian MMMT (12/16) than MMMT of other sites. There were 10 cases that consisted of two types of sarcomas. The synchronous MMMT of uterus and ovary had similar morphology and the types of carcinoma and sarcoma. The tumor cells that spread or metastasized to lymph node, omentum, intestinal wall or skin were all carcinoma cells, and were morphologically consistent with the original tumors. Immunohistochemically, ER and PR were both negative (23/25 in uterine, 8/10 in ovarian tumors). p16 was strongly positive (11/11 in uterine tumors, and 6/6 in ovarian tumors), with similar expression patterns in the carcinoma and sarcoma components. p53 showed mutant-type staining (64%, 21/33) and expressed synchronously in carcinoma and sarcoma components. p53 mutation was found in 35% cases of endometrial carcinoma and 46.7% cases of non-endometrial carcinoma. p53 mutation was also found in only 31.8% cases of heterogenic sarcomas, but in 50% of non-heterogenic sarcomas. Twenty-eight cases (28/33, 85%) presented intact mismatch repair proteins, while 5 cases (5/33, 15%) presented deficient mismatch repair proteins. Conclusions: MMMT in female reproductive system is a rare high-grade biphasic tumor with complex and diverse morphology. The immunohistochemical features are characterized by negative ER/PR and strongly positive p16, mostly mutant p53 and proficient mismatch repair proteins. The patients with a high FIGO stage have worse prognosis.