Dicer prevents activation of the type I interferon pathway in lipid-loaded macrophages

Background

The expression of the endonuclease Dicer in macrophages decreases atherosclerosis and necrotic core formation by producing microRNAs such as miR-10a. This effect of Dicer is associated with enhanced mitochondrial respiration in lipid-loaded macrophages. However, the mechanism by which Dicer-dependent production of miRNAs in lipid-loaded macrophages regulates mitochondrial function is unclear.

Purpose

We aimed to determine the effect of Dicer on lipid-loaded macrophages in the context of atherosclerosis.

Methods

Mice with a myeloid cell-specific knockout of Dicer (Lys-Cre/Dicerflox/flox/Apoe−/− mice [M-Dicer−/−]) and control mice (Lys-Cre/DicerWT/WT/Apoe−/− mice [M-Dicer+/+]) were fed a high-fat diet (HFD) for 24 weeks. The oxygen consumption rate (OCR) in aortic arch plaques was studied ex vivo by Seahorse Flux XF 24 Analyzer. Bone marrow-derived macrophages (BMDMs) were stimulated with oxLDL (100 μg/mL) for 72 h. Lipid-loaded macrophages were used for proteomic analysis by mass spectrometry. RIP-prime- seq was performed in tAgo2 immunoprecipitates (IP) from Dicer+/+ and Dicer−/− BMDMs. The miRNA expression profile was determined in lipid-loaded BMDMs by NanoString technology. Stat1 phosphorylation was determined in lipid-loaded macrophages by Jess automated western blot system (ProteinSimple).

Result

The OCR in aortic arch tissue with plaques was higher than in those without plaques in M-Dicer+/+ mice after 24 weeks of HFD feeding. Dicer knockout in macrophages decreased the OCR in aortic arch tissues with plaques but not in aortic arch tissues without plaques (n=3–4, p<0.05). The proteomic analysis of oxLDL-treated BMDMs indicated that Dicer knockout activated the type I interferon signaling pathway by up-regulating the expression of STAT1/2 and interferon-stimulated genes, such as ISG15. Proteins related to mitochondrial DNA were upregulated (e.g., Dnmt3a) or downregulated (e.g., Tfam) by Dicer knockout (n=5, adj.p<0.05). RIP-prime-seq from BMDMs showed that 1376 transcripts were significantly enriched in the tAgo IP from Dicer+/+ compared with that from Dicer−/− BMDMs (n=3–5, adj.p<0.05) including Dnmt3a and Stat2. STAT1 phosphorylation was increased in Dicer−/− compared with Dicer+/+ BMDMs. Among the 299 miRNAs downregulated by Dicer knockout in lipid-loaded macrophages (n=6, adj.p<0.05), miR-29 and miR-30 have highly conserved binding sites (predicted by TargetScan) for Dnmt3a.

Conclusion

Our results indicate that Dicer expression in lipid-loaded macrophages limits Stat1/2-driven type I interferon response due to mitochondrial damage. This effect may be mediated by the suppression of Dnmt3a by miRNAs such as miR-29 and miR-30. This suggests that targeting Dnmt3a-mediated mitochondrial damage in lipid-loaded macrophages by miRNAs may be therapeutic strategy to limit atherosclerosis.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): DFG

[Clinical effectiveness of fecal microbiota transplantation combined with nutritional support and psychological intervention in patients with "Tetralogy of Tongji"]

Objective: To summarize and analyze the clinical effect of fecal microbiota transplantation (FMT) combined with nutritional support and psychotherapy in patients with "Tetralogy of Tongji" (comprising chronic gastrointestinal dysfunction, mental and psychological disorders, malnutrition, and endocrine disorders). Methods: A longitudinal study was conducted. The inclusion criteria were as follows: (1) patients were under 70 years of age; (2) patients exhibited chronic gastrointestinal dysfunction (in accordance with the Rome IV diagnostic criteria for irritable bowel syndrome ie. chronic functional constipation, diarrhea, abdominal pain and abdominal distention) with onset occurring more than one year previously; (3) patients exhibited malnutrition (body mass index ≤ 18.5 kg/m²); (4) patients exhibited depression, anxiety, or state as diagnosed by a psychologist using the Hamilton anxiety rating scale (HAMA) and the Hamilton depression scale (HAMD); (5) patients were women of childbearing age with amenorrhea or menstrual disorder with a duration ≥6 months. Patients were excluded if they exhibited gastrointestinal bleeding, short bowel syndrome, radiation-induced intestinal injury, intestinal obstruction or inflammatory bowel disease, recurrent/metastatic tumors, systemic infectious diseases, life-threatening systemic comorbidities, intorlerate to nasojejunal, percutaneous gastrostomy / jejunostomy or FMT. The clinical data of 43 patients at Shanghai Tenth People's Hospital exhibiting the "Tetralogy of Tongji" and who received microflora transplantation combined with nutritional support and psychotherapy from June 2017 to June 2021 was prospectively collected. There were 12 males and 31 females with a mean age of 35.2±16.7 years. All 43 patients had chronic gastrointestinal dysfunction. Of these, 24 patients had depression and 19 had anxiety. There were 26 women of reproductive age, including 13 cases of menstrual disorder and 9 cases of amenorrhea. The treatment intervention was a combination of FMT (microflora solution or microflora capsule), nutritional support (enteral nutrition) and psychological intervention. The following were assessed before treatment and 1, 3, 6 months after treatment: (1) gastrointestinal function was assessed using the gastrointestinal symptoms rating scale (GSRS), where a higher score is indicative of more serious gastrointestinal symptoms, and the gastrointestinal quality of life index (GIQLI), where a higher score is indicative of higher quality of life; (2) psychological status was assessed using HAMA and HAMD scores, where a lower score is indicative of reduced severity of anxiety or depression symptoms, respectively; (3) nutritional status was assessed by measurements of total blood protein, albumin, fibrinogen and prealbumin, as well as measurements of body mass and body mass index (BMI); (4) neuroendocrine function was assessed by measurement of blood levels of cortisol, dopamine and noradrenaline, as well as menstruation in women of reproductive age. Results: The follow-up rates at 1, 3 and 6 months after treatment were 90.7% (39/43), 72.1% (31/43) and 55.8% (24/43), respectively. The total effective rate for chronic gastrointestinal dysfunction was 81.4% (35/43), of which the average GSRS score decreased from 29.35±3.56 before treatment to 18.25±2.56 in the sixth month (P<0.001). The average GIQLI score increased from 56.23±10.34 before treatment to 91.04±20.39 in the sixth month (P<0.001). All patients had malnutrition before treatment. After 6 months, their body weight had increased from 40.61±8.88 kg to 50.45±6.23 kg (P<0.001), and BMI had increased from 15.17±1.87 kg/m² to 19.58±1.42 kg/m² (P<0.001). The average total protein level was 60.99± 5.99 g/L before treatment. After 6 months, this had increased to 64.21±4.23 g/L (F=2.715, P=0.022). The average prealbumin level increased from 150.14±56.04 mg/L before treatment to 258.17±86.94 mg/L after 6 months (F=15.124, P<0.001). In this study, 24 patients with depression/depressed state were included. After treatment, the average HAMD score in these patients decreased from 22.79±6.63 before treatment to 9.92±7.24 after 6 months (P<0.001). There were 19 patients with anxiety disorder/anxiety state. After treatment, the average HAMA score in these patients decreased from 17.15±4.34 before treatment to 7.73±4.10 after 6 months (P<0.001). Observing the endocrine efficacy of 26 women of childbearing age, it was found that the effective rate of this treatment on endocrine regulation was 69.2% (18/26). Although there was no significant change in blood cortisol levels after 6 months, average blood dopamine levels decreased from 32.91±10.65 nmol/L before treatment to 13.02±5.58 nmol/L after 6 months (P<0.001). Average blood norepinephrine levels decreased from 49.75±15.23 ng/L before treatment to 19.21±9.58 ng/L after 6 months (P<0.001). Conclusion: The strategy of FMT combined with nutritional support and psychological intervention is effective in improving the symptoms of the "Tetralogy of Tongji".

[Establishment and preliminary clinical application of human intestinal fluid transplantation]

Objective: To explore and establish the preparation system of human intestinal fluid transplantation (HIFT) and HIFT capsule, and to preliminarily apply it to clinic. Methods: Strict standards for donor screening and management were established. The nasojejunal tube was catheterized into the distal jejunum, and then it was connected with an improved disposable sterile negative pressure collection device for the collection of human intestinal fluid. After that, it was prepared into capsules by filtering, adding 10% glycerin protectant and freeze-drying method. The amount of living bacteria was used as the standard of therapeutic dose. The living bacteria amount in fluid is ≥ 5.0×10⁸ /mL and the living bacteria proportion is ≥ 83%; the living bacteria amount in powder is ≥ 2.0×10⁶ /g and the living bacteria proportion is ≥ 81%; The observational indicators included: (1) the basic information of the donor, the amount of living bacteria in the HIF and powder. (2) Preliminary analysis of the treatment for ASD, which combined HIFT capsule with standard FMT capsule, from February to December 2021 (Clinical trial Registration Number: ChiCTR2100043929). Evaluation criteria: Trypan blue staining method was used to detect the living bacteria amount in fluid and powder. The Autism Behavior Checklist (ABC) and Childhood Autism Rating Scale (CARS) were used to evaluate the efficacy. Results: Compared with the parent donor, the standard donor was younger [(25.4±0.9) y vs. (30.7±3.2) y, t=-19.097, P=0.001] and had a lower body mass index [(19.7±0.5) kg/m² vs. (20.8±1.3) kg/m², t=-8.726, P=0.001], more in the living bacteria amount in powder [(7.47±1.52)×10⁶/g vs. (5.03±1.38)×10⁶/g, t=11.331, P=0.031], Chao index (205.4±6.8 vs. 194.2±7.2, t=10.415, P=0.001), and Shannon index (3.25±0.14 vs 2.72±0.27, t=19.465, P=0.001). The differences were statistically significant (all P<0.05). However, there were no significant differences in gender, drainage volume and total number of bacterial liquid colonies between the two groups (all P>0.05). Both the standard donor and the parent donor met the donor screening criteria, and the preparation fluid and powder met the treatment criteria. Eight patients received the treatment of HIFT combined with fecal microbiota transplantation (FMT). Preliminary statistical results showed that HIFT combined with FMT improved ABC and CARS at the 1st, 2nd, 3rd and 4th months. The differences were statistically significant (all P<0.05). No severe adverse reaction occurred. Conclusion: Based on the previous research on FMT preparation system and the clinical technology in our center, this study developed a high standard HIFT preparation system, and explored the clinical study of HIFT combined with FMT, in order to provide an innovative therapy for the treatment of diseases.

[Further improve the standardization construction and development level of fecal microbiota transplantation (FMT) in China]

In the past ten years, the clinical application of fecal microbiota transplantation (FMT) in the treatment of intestinal and extraintestinal diseases has attracted much attention. In China, there are more than 300 hospitals that have developed FMT, but the development of FMT is still in its early stage. The clinical practice of FMT needs to form a standardized system, including management of donors and acceptors, preparation of capsules containing certain gut bacteria, evaluation of effectiveness, and study of fecal microbiota and disease. In order to promote the establishment of the standard system of FMT and the healthy development of FMT, this paper expounds the establishment of the standardization of domestic flora transplantation according to the relevant literature, as well as the experience of 10000 cases and 95300 times of FMT in our center.

[Clinical significance and intervention strategy of gastrointestinal psychiatry]

With the development of global economy and society,the number of patients who suffer from functional gastrointestinal disorders (FGID) and mental illness is growing. In recent years, a substantial amount of high-quality research evidence shows that these two kinds of diseases often coexist, and they are mutually causal, and their common pathophysiology is the abnormal interaction of "bacteria-gut-brain axis". In clinical practice, there are some problems, such as insufficient recognition and attention of both doctors and patients to its clinical manifestations, lack of understanding of pathophysiological mechanism, and lack of overall and integrated views of intervention methods, which may be the main factors of poor curative effect at present. Therefore, according to the global research progress and the author's clinical experience, we put forward a new viewpoint of "gastrointestinal psychiatry", it concluded that clinical intervention strategies needed to include dietary and lifestyle changes as well as multidisciplinary interventions such as probiotics, prebiotic, fecal microbiota transplantation and cognitive psychology. On the basis of gastrointestinal psychiatry, this paper systematically elaborated the diagnosis and treatment of this kind of diseases.

[China guideline for the screening, early detection and early treatment of gastric cancer (2022, Beijing)]

Gastric cancer (GC) is a major digestive tract malignancy in China, which seriously threatens the health of Chinese population. A large number of researches have demons-trated that screening, early detection and early treatment are effective in reducing the incidence and mortality of GC. The development of the guideline for GC screening, early detection and early treatment in line with epidemic characteristics of GC in China will greatly promote the homogeneity and standardization, and improve the effect of GC screening. This guideline was commissioned by the Bureau of Disease Control and Prevention of the National Health Commission. The National Cancer Center of China initiated and convened a working group comprising multidisciplinary experts. Following the World Health Organization Handbook for Guideline Development, this guideline combined the most up-to-date evidence of GC screening, China's national conditions, and practical experience in cancer screening. This guideline provided evidence-based recommendations with respect to the screening population, technology and procedure management, aiming to improve the effect of GC screening and provide scientific evidence for the GC prevention and control in China.

[A prospective randomized controlled study on the effects of compound analgesia in ultra-pulsed fractional carbon dioxide laser treatment of post-burn hypertrophic scars in children]

Objective: To investigate the effects of compound analgesia on ultra-pulsed fractional carbon dioxide laser (UFCL) treatment of post-burn hypertrophic s in children. Methods: A prospective randomized controlled study was conducted. From April 2018 to March 2020, 169 pediatric patients with post-burn hypertrophic s admitted to the First Affiliated Hospital of Air Force Medical University were randomly divided into general anesthesia alone group (39 cases, 19 males and 20 females, aged 35 (21, 48) months), general anesthesia+lidocaine group (41 cases, 23 males and 18 females, aged 42 (22, 68) months), general anesthesia+ibuprofen suppository group (41 cases, 25 males and 16 females, aged 38 (26, 52) months), and three-drug combination group with general anesthesia + lidocaine+ibuprofen suppository (48 cases, 25 males and 23 females, aged 42 (25, 60) months), and the pediatric patients in each group were treated with corresponding analgesic regimens when UFCL was used to treat s, and the pediatric patients were given comprehensive care throughout the treatment process. The pain degree of pediatric patients scar was evaluated by facial expression,legs,activity,cry,and consolability (FLACC) of children's pain behavior scale at 0 (immediately), 1, 2, and 4 h after awakening from the first anesthesia, respectively. At 4 h after awakening from the first anesthesia of postoperative pain assessment, the self-made analgesia satisfaction questionnaire was used to evaluate the satisfaction for the analgesic effect of the pediatric patients or their families, and the satisfaction rate was calculated. Within 2 h after the first operation, the occurrences of adverse reactions of the pediatric patients, such as nausea and vomiting, headache, dizziness, drowsiness, etc, were observed and recorded. Before the first treatment and 1 month after the last treatment, the Vancouver scar scale (VSS) was used to evaluate the pediatric patients scar, and the difference value between the two was calculated. Data were statistically analyzed with least significant difference test, Kruskal-Wallis H test, chi-square test and Fisher's exact probability test. Results: At 0 h after awakening from the first anesthesia, the FLACC scores of pediatric patients in general anesthesia+lidocaine group, general anesthesia+ibuprofen suppository group and three-drug combination group were significantly lower than those in general anesthesia alone group (P<0.01). The FLACC scores of the pediatric patients in anesthesia+ibuprofen suppository group and three-drug combination group were significantly lower than that in general anesthesia+lidocaine group (P<0.01), and the FLACC score of the pediatric patients in three-drug combination group was significantly lower than that in general anesthesia+ibuprofen suppository group (P<0.01). At 1 and 2 h after awakening from the first anesthesia, the FLACC scores of pediatric patients in general anesthesia+ibuprofen suppository group and three-drug combination group were both significantly lower than those in general anesthesia alone group and general anesthesia+lidocaine group (P<0.01), and the FLACC score of the pediatric patients in three-drug combination group was significantly lower than that in general anesthesia+ibuprofen suppository group (P<0.01). At 4 h after awakening from the first anesthesia, the FLACC scores of the pediatric patients in general anesthesia+ibuprofen suppository group and three-drug combination group were significantly lower than those in general anesthesia alone group and general anesthesia+lidocaine group (P<0.01). At 4 h after awakening from the first anesthesia, the satisfactions rate with the analgesic effect in the four groups of pediatric patients or their families were 79.49% (31/39), 85.37% (35/41), 87.80% (36/41), and 97.92% (47/48), respectively. The satisfaction rate of the pediatric patients in three-drug combination group was significantly higher than those in general anesthesia alone group, general anesthesia+lidocaine group, general anesthesia+ibuprofen suppository group. Within 2 h after the first operation, there was no significant difference in the overall comparison of adverse reactions such as nausea and vomiting, headache, dizziness, and drowsiness of pediatric patients among the 4 groups (P>0.05). The VSS scores of pediatric patients before the first treatment, 1 month after the last treatment, and and the difference value between the two in the 4 groups were not significantly different (P>0.05). Conclusions: Three-drug combination for analgesia has a good effect in the treatment of hypertrophic scars after burn in pediatric patients with UFCL. Pediatric patients or their families are highly satisfied with the effect, and the treatment effect and incidence of adverse reactions are similar to other analgesic regimens, so it is recommended to be promoted in clinical practice.

[Preoperative serum creatinine as an independent prognostic biomarker in patients with early-stage cervical adenocarcinoma]

Objective: To investigate the effect of preoperative serum creatinine (Scr) level on the prognosis of patients with early cervical adenocarcinoma (ADC) and its predictive value. Methods: A retrospective review was performed on 199 patients with the International Federation of Gynecology and Obstetrics (FIGO) stage ⅠA1-ⅡA1 and pathology-proven invasive ADC from January 2005 to December 2015. Patients were followed up by phone and outpatient, with a median follow-up time 77.5 (57.0, 114.0) months, 11 cases (5.5%) were missing, 19 cases (10.1%) recurred, and 17 cases (9.0%) died. Multivariate analysis was performed by Cox regression model to analyze the related factors of the prognosis of ADC patients. The optimal cut-off point was determined by the analysis of receiver operating characteristics (ROC), and the predictive value of related factors for prognosis was evaluated by the area under the curve (AUC). Results: The median age of 199 patients was 44.0 (39.0-50.0) years. Overall, 16 patients (8.0%) were stage ⅠA1; 4 patients (2.0%) were stage ⅠA2; 147 patients (74.0%) were stage ⅠB1; 13 patients (6.5%) were stage ⅠB2; 19 patients (9.5%) were stage ⅡA1. The multivariate analysis showed that FIGO stage [4.570 (1.625-12.854)] and elevated Scr [1.065 (1.006-1.128)] were correlated with DFS in patients with early ADC, as well as correlated with OS [4.412 (1.458-13.350) and 1.076 (1.012-1.144), respectively (all P<0.05)]. The optimal cut-off point of Scr level was 75.2 μmoI/L. The AUC showed that the Scr level was a predictor of DFS (AUC=0.677, 95%CI: 0.608-0.742, P=0.006) and OS (AUC=0.677, 95%CI: 0.607-0.741, P=0.012). Conclusions: The preoperative Scr level independently predicts the prognosis of early-stage ADC; patients with Scr levels>75.2 μmoL/L might require more follow-up and adjuvant treatment, as they might have a poorer prognosis.

[Analysis of the characteristics of HIV-1 molecular transmission network among people aged 50 years and above in Pengzhou city of Sichuan province]

Objective: To describe the characteristics of molecular transmission network of newly diagnosed HIV-1 infected patients, analyze their risk factors related to network access and provide a scientific basis for precise prevention of HIV infection. Methods: For 340 blood samples collected from confirmed HIV-1 infection cases aged ≥50 years in Pengzhou city of Sichuan province from April 2019 to August 2021, nested PCR amplification was used to amplify, clean up and splice clips the pol gene region. The phylogenetic tree was constructed by multi-sequence comparison to distinguish subtypes, and the pairwise genetic distance was calculated. When the genetic distance threshold was 0.90%, the number of clusters was the largest (41), and the molecular transmission network was constructed.The χ² test and logistic regression analysis were performed.The software SPSS 19.0 was used for statistical analysis. Results: A total of 340 samples were successfully amplified (97.06%, 330/340) in 330 samples. 6 HIV-1 subtypes identified, including:CRF01_AE(56.67%,187/330), CRF07_BC(27.88%,92/330), B(11.21%,37/330), CRF08_BC(3.33%,11/330), CRF55_01B(0.61%,2/330) and C(0.30%,1/330).The network entry rate was 58.79% (194/330).The results of logistic regression analysis of the risk factors of HIV-1 molecular transmission network in the research subjects showed that compared with illiteracy, junior high school (OR=0.35, 95%CI:0.13-0.97) and high school/technical secondary school (OR=0.14, 95%CI: 0.02-0.97) had lower possibility of network entry. Compared with farmers, unknown occupations (OR=0.40,95%CI: 0.17-0.95) are less likely to enter the network .Compared with CRF01_AE, CRF07_BC (OR=0.20, 95%CI: 0.11-0.35) and CRF08_BC subtype (OR=0.09, 95%CI: 0.02-0.45) were less likely to enter the network. Conclusions: The sources of AIDS transmission among middle-aged and elderly people of rural areas are diversified in Pengzhou city of Sichuan province. AIDS intervention should focus on middle-aged and elderly farmers with low educational level, and strengthen detection and traceability investigation.

[Survival analysis of long-term HIV/AIDS cases aged 15 years and over under antiretroviral treatment in Henan Province from 2002 to 2020]

Objective: To analyze the survival and influencing factors of HIV infections and AIDS cases (HIV/AIDS) aged 15 years and over who had received antiretroviral treatment (ART) for more than 10 years in Henan Province. Methods: In this retrospective cohort study, data of HIV infections and AIDS cases in Henan province were collected from the AIDS Prevention and Control System between January 1, 2002 and December 31, 2020. This study included 20 256 participants alive after 10-year ART with complete baseline and follow-up information, such as demographic characteristics, CD4⁺T lymphocyte count and viral load. Cox proportional risk regression model was used to analyze influencing factors of HIV/AIDS survival. Results: A total of 20 256 participants were followed up for 82 738.2 person-years, with an average follow-up of 4.1 person-years, of which most cases were blood transmission (85.5%) and married (71.2%). The male to female ratio was 1∶1.06 and the age at 10 years of ART was (51.2±8.7) years old. About 88.5% of HIV/AIDS patients received ART in village/township treatment institutions. Overall, there were 2 030 deaths during this period, among which 1 897 were due to AIDS-related diseases (93.5%) and the case fatality rate was 9.4% (1 897/20 256). Cox proportional risk regression model showed that participants aged 40-54, 55-69, and ≥70 years had a higher risk of death compared to those aged 25-39, with adjusted HRs (95%CI) of 1.57 (1.19-2.08), 3.78 (2.86-4.99), and 6.17 (4.33-8.79), respectively. Participants with the initial CD4⁺T lymphocyte count about 200-349/μl and<200/μl had a higher risk of death compared to those with initial CD4⁺T lymphocyte count ≥350/μl, with adjusted HRs (95%CI) of 1.81 (1.61-2.04) and 3.64 (3.20-4.15), respectively. Participants with the initial viral load outcome ≥1 000 copies/ml had a higher risk of death compared to those with the initial viral load outcome<1 000 copies/ml, with adjusted HRs (95%CI) of 1.73 (1.52-1.97). Participants receiving the second-line ART had a lower risk of death compared to those receiving the first-line ART, with adjusted HRs (95%CI) of 0.12 (0.11-0.14). Conclusion: From 2002 to 2020, the survival rate of HIV/AIDS treated with ART for more than 10 years is high in Henan Province. Age, CD4⁺T lymphocyte count and viral load are influencing factors of HIV/AIDS survival.

[Exploration on teaching reform of cancer epidemiology course]

This study aims to explore optimized teaching mode of cancer epidemiology for undergraduates, and provide scientific ideas and basis for improving teaching quality. Non-randomized concurrent control study was used. Undergraduates, enrolled in 2018, from the department of preventive medicine in A and B medical universities were selected as research objects. Traditional teaching mode was used for cancer epidemiology course in A medical university, and innovative teaching mode named "one core, four dimensions" was adopted in B medical university. After the course, questionnaire method was used to investigate self-cognition of students, teaching satisfaction and class preparation time of teachers in B Medical University. The post-class test method was used to compare the students' grades of cancer epidemiology in the two universities. The results indicated that among the 58 students of B medical university, 94.83% (55/58) students were familiar with common types of epidemiological studies and 86.21% (50/58) mastered the evaluation indicators of screening research. Among the nine teaching faculties from B medical university, seven reported that the new teaching plan helped students to learn frontier knowledge of cancer epidemiology, and eight reported the new teaching model was conducive to the interaction between teachers and students. The text score of students in B medical university was 50.34±4.90, significantly higher than that in A medical university (46.21±4.91, t=5.20, P<0.001). The optimized teaching mode of cancer epidemiology is highly praised by students and teachers, which has the potential to improve students' grasp of cancer epidemiology, the ability to combine theory with practice, and the teaching effect of cancer epidemiology.

A novel polychromator calibration method for Thomson scattering diagnostics

Polychromators are most frequently used in Thomson scattering (TS) diagnostics to analyze the scattered light spectrum and intensity so that the plasma electron temperature (T_e) and density (n_e) can be derived. For T_e measurements, the spectral response of the polychromator channels and the relative spectral responsivities need to be calibrated. The spectral response is calibrated with a bromine tungsten lamp and a monochromator in a conventional way. A novel method for calibrating the relative spectral responsivities of the polychromators is described in detail. A broadband pulsed Light Emission Diode (LED) is used, which has a spectral irradiance similar to that of the TS spectrum, and the LED can be driven in pulse mode with the pulse width similar to the TS signal pulse width of about 10-20 ns full width at half maximum. This new method allows for the calibration to be done after the polychromator is fully installed, and in situ system calibration can be easily performed, showing the advantages of accuracy, simplicity, efficiency, and flexibility. For n_e measurements, absolute sensitivity calibration is done by Rayleigh scattering with argon gas. Formulas for calculating the plasma density from the calibration data and the polychromator signals from the off-laser wavelength channels are presented.