[Treatment of patent ductus arteriosus in very preterm infants in China]

Objective: To describe the current status and trends in the treatment of patent ductus arteriosus (PDA) among very preterm infants (VPI) admitted to the neonatal intensive care units (NICU) of the Chinese Neonatal Network (CHNN) from 2019 to 2021, and to compare the differences in PDA treatment among these units. Methods: This was a cross-sectional study based on the CHNN VPI cohort, all of 22 525 VPI (gestational age<32 weeks) admitted to 79 tertiary NICU within 3 days of age from 2019 to 2021 were included. The overall PDA treatment rates were calculated, as well as the rates of infants with different gestational ages (≤26, 27-28, 29-31 weeks), and pharmacological and surgical treatments were described. PDA was defined as those diagnosed by echocardiography during hospitalization. The PDA treatment rate was defined as the number of VPI who had received medication treatment and (or) surgical ligation of PDA divided by the number of all VPI. Logistic regression was used to investigate the changes in PDA treatment rates over the 3 years and the differences between gestational age groups. A multivariate Logistic regression model was constructed to compute the standardized ratio (SR) of PDA treatment across different units, to compare the rates after adjusting for population characteristics. Results: A total of 22 525 VPI were included in the study, with a gestational age of 30.0 (28.6, 31.0) weeks and birth weight of 1 310 (1 100, 1 540) g; 56.0% (12 615) of them were male. PDA was diagnosed by echocardiography in 49.7% (11 186/22 525) of all VPI, and the overall PDA treatment rate was 16.8% (3 795/22 525). Of 3 762 VPI who received medication treatment, the main first-line medication used was ibuprofen (93.4% (3 515/3 762)) and the postnatal day of first medication treatment was 6 (4, 10) days of age; 59.3% (2 231/3 762) of the VPI had been weaned from invasive respiratory support during the first medication treatment, and 82.2% (3 092/3 762) of the infants received only one course of medication treatment. A total of 143 VPI underwent surgery, which was conducted on 32 (22, 46) days of age. Over the 3 years from 2019 to 2021, there was no significant change in the PDA treatment rate in these VPI (P=0.650). The PDA treatment rate decreased with increasing gestational age (P<0.001). The PDA treatment rates for VPI with gestational age ≤26, 27-28, and 29-31 weeks were 39.6% (688/1 737), 25.9% (1 319/5 098), and 11.4% (1 788/15 690), respectively. There were 61 units having a total number of VPI≥100 cases, and their rates of PDA treatment were 0 (0/116)-47.4% (376/793). After adjusting for population characteristics, the range of standardized ratios for PDA treatment in the 61 units was 0 (95%CI 0-0.3) to 3.4 (95%CI 3.1-3.8). Conclusions: From 2019 to 2021, compared to the peers in developed countries, VPI in CHNN NICU had a different PDA treatment rate; specifically, the VPI with small birth gestational age had a lower treatment rate, while the VPI with large birth gestational age had a higher rate. There are significant differences in PDA treatment rates among different units.

Is a Deep Learning Based Segmentation Model Trained on planning CTs Transferable for Segmentation of Organs at Risk in Replanning CTs?

PURPOSE/OBJECTIVE(S)

To evaluate the differences in the segmentation of organs at risk (OARs) in planning and replanning radiotherapy CT images, and to assess the feasibility of using deep learning segmentation models trained on planning radiotherapy CTs for the contouring of OARs in replanning radiotherapy CTs.

MATERIALS/METHODS

A total of 82 pairs of corresponding planning and replanning CT images from clinics were collected for contouring OARs in nasopharyngeal carcinoma patients. 14 of these were selected as the test set, and 20 OARs were selected for analysis. The deep learning model utilized in this study was the medical image segmentation framework, nnUNet. The test set of 14 replanning radiotherapy CT images was processed using different models trained on three training strategies: (A) 68 sets of planning CTs; (B) 68 sets of replanning CTs; (C) a mixed set of both 34 planning and replanning CTs. Additionally, the model trained by strategy A was also tested on the test set of 14 planning CT images. The segmentation results were evaluated using the Dice Similarity Coefficient (DSC).

RESULTS

The average DSCs of the models trained using strategies A, B, and C on the test set of replanning CTs were (A) 0.54±0.28; (B) 0.57±0.28; (C) 0.56±0.27, respectively. On the test set of planning CTs, the average DSC of the model trained using strategy A was 0.64±0.25. These showed that when processing replanning CTs, the segmentation accuracy of the model trained using strategy A was significantly lower than that of the model trained using strategy B (p < 0.01), while the accuracy of the model trained using strategy C was improved compared to that of strategy A but still inferior to that of strategy B. Furthermore, the model trained on planning radiotherapy CTs alone (strategy A) showed a large difference in accuracy when processing planning and replanning CTs separately (p < 0.001).

CONCLUSION

There is a significant difference in the segmentation of OARs in planning and replanning radiotherapy CT images, and the deep learning segmentation model constructed based on planning radiotherapy CTs is not suitable for the segmentation of OARs in replanning radiotherapy CT images. This highlights the need for re-modeling based on replanning CTs and also inspires us to incorporate the prior information contained in planning CTs and their labels into the OARs contouring of corresponding replanning radiotherapy CTs. These will, to some extent, provide insights into potential avenues for enhancing the future segmentation efficacy of adaptive radiotherapy.

CAU-Net: An Improved Attention U-Net for CT Head and Neck Organs at Risk Contouring

PURPOSE/OBJECTIVE(S)

Segmentation of head and neck (H&N) organs at risk (OARs) is an intricate process, we propose Contest- extractor Attention U-Net (CAU-Net) to improve the segmentation accuracy of OARs contours by addressing the problem of limited accuracy of 2D segmentation algorithms in current radiotherapy techniques.

MATERIALS/METHODS

A total of 60 patients from CSTRO2019's H&N dataset containing 22 organs, were available to train and evaluate a prototype deep learning-based normal tissue 2D auto-segmentation algorithm. Our CAU-Net is based on U-Net, by using the edge attention module to enhance the boundary representation, the null convolution block in the context extraction module to encode high-level semantic feature information, and the convolution of the sensory field to assign to different targets. A Dice loss function combine contour loss function was used in training the models. The contour loss function was improved to segment the target regions by the weights of different organ occurrences and the region assignment of false positives and false negatives to accurately predict the boundary structure. The OARs were delineated by a single experienced physician. A subset of 10 cases was withheld from training and used for validation. On those, we set three different deep-learning networks trained with CSTRO and compared them to the gold data: A) CAU-Net, B) nnUNet, and C) UNet++. To test its applicability, we used another public H&N dataset Public Domain Database for Computational Anatomy (PDDCA) containing 8 organs with 47 patients, among which 10 cases were used for validation: D) CAU-Net with the PDDCA, E) UNet2022 with the PDDCA. The Dice similarity coefficient (DSC) was used to measure the overlap between the results of the gold data and the automated segmentations.

RESULTS

The average DSC scores for method A, B, and C across all OARs in the 10 evaluation cases were 0.67±0.08, 0.58±0.11 and 0.62±0.12, respectively. The difference in mean DSC scores was significant (p<0.05). The A/B difference was significant in Lens-L, Lens-R and Pituitary. Method A scored the highest DSC in all OARs except for the Spinal Cord, Mandible-L and Mandible-R. 16 OARs showed DSC≥0.6 on CSTRO. Method D, and E achieved 0.84±0.10 and 0.83±0.09 average DSC respectively. All OARs showed DSC≥0.7 on PDDCA.

CONCLUSION

The CAU-Net proposed by us achieved better results than the baseline network for H&N OAR segmentation. This new development will provide the possibility of H&N organ segmentation and rapid diagnosis of radiotherapy. All the networks trained with PDDCA scored higher than CSTRO. Auto segmentation results can differ significantly when the same algorithm is trained on data from different institutions.

A Feasible Study for Auto Planning and Auto Re-Planning for Nasopharyngeal Carcinoma (NPC) Adaptive Radiation Therapy (ART)

PURPOSE/OBJECTIVE(S)

To explore the necessity of Image Guided Radiation Therapy (IGRT) for Nasopharyngeal Carcinoma (NPC) adaptive radiation therapy (ART), and evaluate the consistency and robustness of auto re-planning during ART.

MATERIALS/METHODS

Eleven NPC patients were enrolled in this study at one institution. We used a CT-integrated linear accelerator, which integrates a 16-slice helical CT to acquire diagnostic-grade fan-beam CT (FBCT) for IGRT. Electron density accuracy from FBCT provides a solid foundation for accurate radiation dose calculation. PGTVp, PTV1 and PTV2 prescription dose are 69.96 Gy, 60.06 Gy and 54.12 Gy with 33 fractions. All ROIs, including Targets and OARs, were auto delineated via a treatment planning system (TPS), and modified by a senior physician with more than 15-year experience to confirm that they follow the clinical requirement. An initial plan (Plan A) was automatically generated based on the first CT-Sim images on the TPS. Another adjusted re-plan (Plan B) was also automatically generated based on the second CT-Sim images after 20 fractions of treatment for ART implementation. During the whole course of the 33 fractions delivery, there are 20 fractions Plan A (with 4 weekly IGRTi, i = 1∼4) and 13 fractions Plan B (with 3 weekly IGRTj, j = 5∼7). After carefully rigid registration between the CT-Sim images and their following weekly FBCT images, we copied Plan A and Plan B to IGRTi and IGRTj, respectively. Plan_IGRT would be re-calculated for dose evaluation. In addition, the Plan A was copied to the second CT-Sim (Plan A_2nd CT-Sim) after first CT-Sim and second CT-Sim rigid images registration.

RESULTS

There is a significant target volume change of -5%±4%, -3%±3%, and -5%±3% from Plan A to Plan B, for PGTVp, PTV1 and PTV2 (p<0.05), respectively. All the Plan A and Plan B could be generated within 210.2s±1.4s, which is more time-saving than manual planning greatly, and there is no statistical difference between Plan A and Plan B of the plan quality index (p>0.05). The plans for IGRT7 are inferior to the plans for IGRT5 with higher V110% for PGTVp (4.40%±8.60% for Plan A, 2.37%±8.91% for Plan B). PlanA_2nd CT-Sim for each patient is inferior to Plan B, with higher V110% for PGTVp (19.12%±18.91%), lower V100% for PTV2 (-2.84%±2.89%) and higher Dmax for Brainstem (315.88 cGy ± 190.39 cGy) statistically. Furthermore, all the Plan B_IGRTj are superior to Plan A_IGRTj, with the dose index difference of -17.50% ± 23.15%/-15.47% ± 14.85%, 2.45% ± 3.23%/2.31% ± 3.09% and -194.03 cGy ± 221.91 cGy/-170.07 cGy ± 168.41 cGy for V110% of PGTVp, V100% for PTV2 and Dmax of Brainstem for j = 5/7 (p<0.05), respectively.

CONCLUSION

The world's first integrated CT-Linac platform, equipped with FBCT, can provide a diagnostic-quality FBCT for achieve offline ART. It is necessary for NPC patients to have the IGRT, ART and re-planning after 20 fractions treatment, for the target volumes change sharply. Auto planning and auto re-planning for NPC ART are able to maintain the plan consistency and robustness while shorten the planning time.

[The triglyceride glucose index predicts the risk of nonfatal cardio-cerebrovascular disease in the Beijing community: a prospective cohort study]

Objective: To explore the characteristics of the association between the triglyceride glucose (TyG) index and nonfatal cardio-cerebrovascular disease risk in a community population. Method: This was a prospective cohort study. From December 2011 to April 2012, the first investigation was conducted among subjects with more than 40-year old who were from Shijingshan district and Pingguoyuan community in Beijing. The second investigation was conducted from April to October 2015. All the subjects were divided into three groups according to the tertile of the TyG index at baseline. The multivariate Cox proportional risk regression model was established to explore the correlation between the TyG index and nonfatal cardio-cerebrovascular disease risk and the Kaplan-Meier survival curve of the TyG index group was drawn. Subgroup analyses were performed according to age, gender, body mass index, type 2 diabetes mellitus (T2DM), hypertension, and hyperlipidemia to determine the correlation characteristics between the TyG index and nonfatal cardio-cerebrovascular disease among subgroups. Results: A total of 9 577 subjects were finally included to analyze. The mean follow-up time of this study was (34.14±3.84) months. During the follow-up, 363 subjects (3.8%) occurred nonfatal cardio-cerebrovascular disease. The multivariate Cox regression analysis results showed that the hazard ratio (HR) of nonfatal cardio-cerebrovascular disease in the high TyG index group was 1.54 (95%CI 1.19-1.98), 1.60 (95%CI 1.23-2.10), and 1.57 (95%CI 1.20-2.05) in the three models, compared with the low TyG index group. The Kaplan-Meier analysis showed that the risk of nonfatal cardio-cerebrovascular disease increased from the low-TyG index group to the high-TyG index group (P=0.015). In the six subgroups analysis, only gender was shown to have a significant interaction effect with the TyG index and nonfatal cardio-cerebrovascular disease risk. In the female population, the risk of nonfatal cardio-cerebrovascular disease is significantly increased with the increase in the TyG index level (P<0.001). Conclusions: A high TyG index is independently related to the increased risk of nonfatal cardio-cerebrovascular disease in the Beijing community population. Gender has a significant interaction with the TyG index and nonfatal cardio-cerebrovascular disease risk. Therefore, the TyG index may be a useful marker to predict the nonfatal cardio-cerebrovascular disease risk of a community population.

[Correlation analysis of anterior pituitary hormone and tumor size in patients with pituitary adenomas]

Objective: To summarize the correlation between anterior pituitary function and tumor size in patients with different hormone-secreting pituitary adenomas. Methods: This was a retrospective case series study. The clinical data of 1 946 patients with pituitary adenoma hospitalized in the First Medical Center of Chinese PLA General Hospital from January 1, 2005, to December 31, 2020, were collected. The correlation between tumor size and anterior pituitary hormone levels was analyzed using Spearman rank correlation analysis in different types of pituitary adenomas. Results: The median age of the 1 946 patients was 45.1 years, of which 857 (44.0%) were men. The maximum tumor diameter of the patients [M (Q₁, Q₃)] was 22 (14, 30) mm. Tumor size in nonfunctioning adenomas (n=1 191) was negatively correlated with adrenocorticotropic hormone (ACTH) (r=-0.11, P<0.001), growth hormone (r=-0.13, P<0.001), and luteinizing hormone (men: r=-0.26, P<0.001, women: r=-0.31, all P<0.001). The tumor size of somatotropic adenomas (n=297) was positively correlated with growth hormone (r=0.46, P<0.001), but negatively correlated with male testosterone (r=-0.41, P<0.001). The tumor size of ACTH-secreting pituitary adenomas (n=155) was positively correlated with the ACTH level at 8∶00 AM (r=0.25, P<0.001); however, no correlation was found with cortisol at 8∶00 AM (P>0.05). The tumor size of prolactinomas (n=303) was positively correlated with the prolactin level (men: r=0.34, P=0.001; women: r=0.13, P=0.070). Conclusions: The correlation between the function of the anterior pituitary and size of the tumor depends on the cellular origin of the pituitary adenoma and specific type of hormone secretion. In somatotroph adenomas, ACTH-secreting pituitary adenomas, and prolactinomas, there is a positive correlation between tumor size and level of hormones secreted by the corresponding tumors. In patients with nonfunctioning adenomas, the tumor size was negatively correlated with the hormone levels of the pituitary-adrenal and pituitary-growth hormone axes.

LTBI-negative close contacts of tuberculosis are more likely to develop the disease: enlightenment and lessons from a cluster outbreak

Background

Tuberculosis (TB) prevention and control among groups living together, such as students, workers, older adults in nursing homes, and prisoners, present many challenges due to their particular age and environmental factors, which can make them more susceptible to TB clusters with significant societal impact. This study aimed to evaluate a TB cluster outbreak epidemic in a university and provide suggestions for improving TB control strategies for groups living together.

Methods

Pulmonary TB screening and close-contact investigation were conducted using acid-fast staining, sputum culture, GeneXpert testing, tuberculin skin testing (TST), interferon-gamma release assay (IGRA), and chest computed tomography (CT). GraphPad Prism 9.5.1 was utilized for data analysis. Collected epidemic data were comprehensively analyzed by rate comparison.

Results

The TB cluster outbreak epidemic was identified with an index case confirmed positive. The initial screening was conducted on potential close contacts of the index case, and the TST's positive rate (diameter ≥ 5 mm) and strong positive rate (diameter ≥ 15 mm) among these close contacts were 65.60% (21/32) and 34.40% (11/32), respectively. Moreover, the latent TB infection (LTBI) rate (diameter ≥ 10 mm) was 43.75% (14/32), and the IGRA's positive rate was 9.30% (3/32). Chest CT scans did not reveal any abnormalities. Surprisingly, 5 of the close contacts developed active TB in the second screening, accompanied by changes from negative to positive TST and/or IGRA results, after 3 months of follow-up. Accordingly, we expanded the screening scope to include another 28 general contacts. We found that the positive rate (78.00%, 25/32), strong positive rate (50.00%, 16/32), and LTBI rate (62.50%, 20/32) of the 32 close contacts were significantly higher than those of the additional general contacts (28.00%, 8/28; 14.3%, 4/28; 25.00%, 7/28), as indicated by p < 0.05.

Conclusion

In the event of an epidemic TB outbreak, it is essential to rapidly identify the source of infection and initiate timely screening of close contacts. The initial screening should be focused on individuals without LTBI, who are at higher risk of developing TB. In purified protein derivative-negative individuals living in groups, additional vaccination or revaccination with Bacille Calmette-Guérin may help prevent cluster outbreaks of TB.

Clinical characteristics of patients with non-tuberculous mycobacterial pulmonary disease: a seven-year follow-up study conducted in a certain tertiary hospital in Beijing

Background

The incidence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) has increased in recent years. However, the clinical and immunologic characteristics of NTM-PD patients have received little attention.

Methods

NTM strains, clinical symptoms, underlying diseases, lung CT findings, lymphocyte subsets, and drug susceptibility tests (DSTs) of NTM-PD patients were investigated. Then, the counts of immune cells of NTM-PD patients and their correlation were evaluated using principal component analysis (PCA) and correlation analysis.

Results

135 NTM-PD patients and 30 healthy controls (HCs) were enrolled from 2015 to 2021 in a certain tertiary hospital in Beijing. The number of NTM-PD patients increased every year, and Mycobacterium intracellulare (M. intracellulare), M. abscessus, M. avium, and M. kansasii were the major pathogens of NTM-PD. The main clinical symptoms of NTM-PD patients were cough and sputum production, and the primary lung CT findings were thin-walled cavity, bronchiectasis, and nodules. In addition, we identified 23 clinical isolates from 87 NTM-PD patients with strain records. The DST showed that almost all of M. abscessus and M. avium and more than half of the M. intracellulare and M. avium complex groups were resistant to anti-tuberculosis drugs tested in this study. M. xenopi was resistant to all aminoglycosides. M. kansasii was 100% resistant to kanamycin, capreomycin, amikacin, and para-aminosalicylic acid, and sensitive to streptomycin, ethambutol, levofloxacin, azithromycin, and rifamycin. Compared to other drugs, low resistance to rifabutin and azithromycin was observed among NTM-PD isolates. Furthermore, the absolute counts of innate and adaptive immune cells in NTM-PD patients were significantly lower than those in HCs. PCA and correlation analysis revealed that total T, CD4⁺, and CD8⁺ T lymphocytes played an essential role in the protective immunity of NTM-PD patients, and there was a robust positive correlation between them.

Conclusion

The incidence of NTM-PD increased annually in Beijing. Individuals with bronchiectasis and COPD have been shown to be highly susceptible to NTM-PD. NTM-PD patients is characterized by compromised immune function, non-specific clinical symptoms, high drug resistance, thin-walled cavity damage on imaging, as well as significantly reduced numbers of both innate and adaptive immune cells.

Shape Adjustment and Experimental Study of a Shape Memory Cable (SMC) Structure

Large deployable cable net antennas have attracted extensive attention worldwide because of their simple structure and high storage ratio. The cable net structure is affected by long exposure in a harsh space environment during satellite operation, resulting in large thermal deformation and stress relaxation, which leads to a degradation of antenna performance. To address the thermal deformation of the cable net structure, a shape memory cable (SMC) net structure model was proposed with surface accuracy as the research objective. Specifically, we aimed to utilize its phase transition characteristics to adjust the thermal deformation of cable net structure and improve its surface accuracy. A shape memory cable net structure model with a diameter of 2.2 m was built, and a normal temperature experiment and high- and low-temperature experiments were carried out. High- and low-temperature test refers to environmental simulation testing of shape memory cable net structures under high- and low-temperature conditions. This was done to determine whether the adjustment method for surface accuracy meets the requirements. The results showed that the shape memory alloy wire has a relatively stable ability to adjust the surface accuracy of the cable net structure at room temperature. During temperature cycling, the thermal deformation of the shape memory cable net structure is slight, and the surface accuracy is good. Compared with ordinary cable net structures, the shape memory cable net structure has improved surface accuracy by 44.4% and 45.2% at high and low temperatures, respectively. This proved the effectiveness of the method for adjusting surface accuracy. These experimental results offer guiding significance for engineering applications.

[Long-term outcome of EVAHEART I implantable ventricular assist device for the treatment of end stage heart failure: clinical 3-year follow-up results of 15 cases]

Objective: To evaluate the long-term efficacy and safety of the implantable ventricular assist system EVAHEART I in clinical use. Methods: Fifteen consecutive patients with end-stage heart failure who received left ventricular assist device therapy in Fuwai Hospital from January 2018 to December 2021 were enrolled in this study, their clinical data were retrospectively analyzed. Cardiac function, liver and kidney function, New York Heart Association (NYHA) classification, 6-minute walk distance and quality of life were evaluated before implantation and at 1, 6, 12, 24 and 36 months after device implantation. Drive cable infection, hemolysis, cerebrovascular events, mechanical failure, abnormally high-power consumption and abnormal pump flow were recorded during follow up. Results: All 15 patients were male, mean average age was (43.0±7.5) years, including 11 cases of dilated cardiomyopathy, 2 cases of ischemic cardiomyopathy, and 2 cases of valvular heart disease. All patients were hemodynamically stable on more than one intravenous vasoactive drugs, and 3 patients were supported by preoperative intra aortic balloon pump (IABP). Compared with before device implantation, left ventricular end-diastolic dimension (LVEDD) was significantly decreased ((80.93±6.69) mm vs. (63.73±6.31) mm, P<0.05), brain natriuretic peptide (BNP), total bilirubin and creatinine were also significantly decreased ((3 544.85±1 723.77) ng/L vs. (770.80±406.39) ng/L; (21.28±10.51) μmol/L vs. (17.39±7.68) μmol/L; (95.82±34.88) μmol/L vs. (77.32±43.81) μmol/L; P<0.05) at 1 week after device implantation. All patients in this group were in NYHA class Ⅳ before implantation, and 9 patients could recover to NYHA class Ⅲ, 3 to class Ⅱ, and 3 to class Ⅰ at 1 month after operation. All patients recovered to class Ⅰ-Ⅱ at 6 months after operation. The 6-minute walk distance, total quality of life and visual analogue scale were significantly increased and improved at 1 month after implantation compared with those before operation (P<0.05). All patients were implanted with EVAHEART I at speeds between 1 700-1 950 rpm, flow rates between 3.2-4.5 L/min, power consumption of 3-9 W. The 1-year, 2-year, and 3-year survival rates were 100%, 87%, and 80%, respectively. Three patients died of multiple organ failure at 412, 610, and 872 d after surgery, respectively. During long-term device carrying, 3 patients developed drive cable infection on 170, 220, and 475 d after surgery, respectively, and were cured by dressing change. One patient underwent heart transplantation at 155 d after surgery due to bacteremia. Three patients developed transient ischemic attack and 1 patient developed hemorrhagic stroke events, all cured without sequelae. Conclusion: EVAHEART I implantable left heart assist system can effectively treat critically ill patients with end-stage heart failure, can be carried for long-term life and significantly improve the survival rate, with clear clinical efficacy.

NLRP3 Disturbs Treg/Th17 Cell Balance to Aggravate Apical Periodontitis

Apical periodontitis is an inflammatory condition that is considered an immunological reaction of the periapical tissue to invading bacteria and their pathogenic components. Recent research has revealed that NLR family pyrin domain containing 3 (NLRP3) is crucial to the pathogenesis of apical periodontitis and serves as a link between innate and adaptive immunity. The balance between regulatory T-cell (Treg) and T helper cell 17 (Th17 cell) determines the direction of the inflammatory response. Therefore, this study aimed to investigate whether NLRP3 exacerbated periapical inflammation by disturbing Treg/Th17 balance and the underlying regulatory mechanisms. In the present study, NLRP3 was raised in apical periodontitis tissues as opposed to healthy pulp tissues. Low NLRP3 expression in dendritic cells (DCs) increased transforming growth factor β secretion while decreasing interleukin (IL)-1β and IL-6 production. The Treg ratio and IL-10 secretion rose when CD4⁺ T cells were cocultured with DCs primed with IL-1β neutralizing antibody (anti-IL-1β) and specific small interfering RNA (siRNA) targeting NLRP3 (siRNA NLRP3), but the proportion of Th17 cells and IL-17 release dropped. Furthermore, siRNA NLRP3-mediated suppression of NLRP3 expression aided Treg differentiation and elevated Foxp3 expression as well as IL-10 production in CD4⁺ T cells. Inhibition of NLRP3 activity by MCC950 boosted the percentage of Tregs while decreasing the ratio of Th17 cells, leading to reduced periapical inflammation and bone resorption. Nigericin administration, however, exacerbated periapical inflammation and bone destruction with an unbalanced Treg/Th17 response. These findings demonstrate that NLRP3 is a pivotal regulator by regulating the release of inflammatory cytokines from DCs or directly suppressing Foxp3 expression to disturb Treg/Th17 balance, thus exacerbating apical periodontitis.

Effect of clay supplementation on growth performance of broiler chickens: a systematic review and meta-analysis

1. This review assessed the effect of dietary clay supplementation as a drug and toxin adsorbent on broiler growth performance as a meta-analysis.2. A total of 33 eligible studies were included in the present study after identification and evaluation from online databases. Standardised mean differences (SMD) with corresponding 95% confidence intervals were computed with a fixed-effects model.3. The results indicated that clay supplementation significantly improved broiler daily gain (P < 0.001) and feed conversion ratio (P < 0.001), but did not affect feed intake (P = 0.954). Results of subgroup analysis showed that zeolite clay had the most stable medium improvement effect on FCR, while kaolin had a large effect. In addition, male broilers and Cobb or Ross broilers were more sensitive to the addition of clay, and the best supplemental levels, in general, were 10 g/kg to 30 g/kg.4. Meta-regression analysis showed that clay supplemental level and sex of broilers may be important factors in the effect of clay on ADG and FCR of broilers, respectively. The sensitivity analysis showed high stability of the results and no significant publication bias was found with funnel plot analysis and Egger's or Begg's test (P > 0.05).5. In conclusion, an appropriate addition level is a prerequisite for effective clay application. Kaolin and zeolite clays seem to be more suitable for enhancing broiler growth performance, and the value of clay is amplified in specific broiler breeds.

Research progress on specific and non-specific immune effects of BCG and the possibility of BCG protection against COVID-19

Bacille Calmette-Guérin (BCG) is the only approved vaccine for tuberculosis (TB) prevention worldwide. BCG has an excellent protective effect on miliary tuberculosis and tuberculous meningitis in children or infants. Interestingly, a growing number of studies have shown that BCG vaccination can induce nonspecific and specific immunity to fight against other respiratory disease pathogens, including SARS-CoV-2. The continuous emergence of variants of SARS-CoV-2 makes the protective efficiency of COVID-19-specific vaccines an unprecedented challenge. Therefore, it has been hypothesized that BCG-induced trained immunity might protect against COVID-19 infection. This study comprehensively described BCG-induced nonspecific and specific immunity and the mechanism of trained immunity. In addition, this study also reviewed the research on BCG revaccination to prevent TB, the impact of BCG on other non-tuberculous diseases, and the clinical trials of BCG to prevent COVID-19 infection. These data will provide new evidence to confirm the hypotheses mentioned above.

Anticeramide Improves Sjögren's Syndrome by Blocking BMP6-Induced Th1

T-cell dysfunction has been shown to play an important role in the pathogenesis of Sjögren's syndrome (SS). In recent studies, the increased expression of BMP6 has been reported to be related to SS. However, the roles that BMP6 plays in immune homeostasis in the development of SS as well as the downstream signals activated by BMP6 remain unclear. In this study, we investigated the effects and molecular mechanisms of BMP6 on naive CD4⁺ T cells, showing that BMP6 could upregulate interferon (IFN)-γ secretion from CD4⁺ T cells through a ceramide/nuclear factor-κB pathway, with no effect on T-cell activation or proliferation. Moreover, an in vivo study showed that anticeramide treatment (myriocin) for an SS animal model (NOD/LtJ mice) could significantly decrease the IFN-γ expression and Th1 frequency in the salivary glands and suppress the inflammation infiltration in salivary glands and maintain the salivary flow rates, both of which reflect SS-like symptoms. This study identifies a promising target that could effectively attenuate the abnormal state of CD4⁺ T cells and reverse the progression of SS.

Plant-Based Diet and Risk of Frailty in Older Chinese Adults

OBJECTIVES

This study examined the relationship between the consumption of plant-based diet and frailty in older Chinese adults.

DESIGN

Prospective cohort study.

SETTING

Community-based setting in 22 provinces of China.

PARTICIPANTS

The final sample included data from 3990 older adults from 2011-2014 from the Chinese Longitudinal Healthy Longevity Survey.

MEASUREMENTS

A plant-based diet index (PDI) was calculated based on a qualitative food frequency questionnaire. Frailty was defined using modified Fried criteria. A Generalized Estimating Equation was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for frailty. We further performed subgroup analyses stratified by sex and lifestyle factors.

RESULTS

557 cases of frailty were observed. After adjustment for covariates, the RR for frailty of a high PDI was 0.792 (95% CI: 0.644-0.973), relative to a low PDI. During follow-up, compared with respondents with a continually low PDI, the respondents with a continually high PDI had a significantly reduced risk of frailty (RR = 0.683, 95% CI: 0.514-0.908). In further subgroup analysis, a consistently high PDI over time resulted in a significantly reduced risk of frailty for male (RR = 0.591, 95% CI: 0.391-0.893); for never smokers (RR = 0.670, 95% CI: 0.458-0.979); for people who did never consume alcohol (RR = 0.654, 95% CI: 0.454-0.941); and for people with current or former exercise habits (RR = 0.488, 95% CI: 0.313-0.762).

CONCLUSION

Plant-based diet was associated with low risk of frailty in men and in older adults with healthy lifestyle. These findings stress that plant-based diet should be recommended as a dietary strategy to prevent and reduce frailty in older adults; in addition, more dietary interventions along with lifestyle modification should be adopted to promote successful ageing, especially for women.

[Study on nomograph predicting the risk of type 2 diabetes mellitus in Beijing community adults]

Objective: Development and validation of a nomogram for predicting the 4-year incidence of type-2 diabetes mellitus (T2DM) in a Chinese population was attempted. Methods: This prospective cohort study was conducted in Shijingshan District Pingguoyuan Community (Beijing, China) from December 2011 to April 2012 among adults aged≥40 years not suffering from T2DM. Finally, 8 058 adults free of T2DM were included with a median duration of follow-up of 4 years. Participants were divided into a modeling group and verification group using simple random sampling at a ratio of 7∶3. Univariate and multivariate Cox proportional risk models were applied to identify the independent risk predictors in the modeling group. A nomogram was constructed to predict the 4-year incidence of T2DM based on the results of multivariate analysis. The Concordance Index and calibration plots were used to evaluate the differentiation and calibration of the nomogram in both groups. Results: A total of 5 641 individuals were in the modeling group and 2 417 people were in the validation group, of which 265 and 106 had T2DM, respectively, at 4-year follow-up. In the modeling group, age (HR=1.349, 95%CI 1.011-1.800), body mass index (HR=1.347, 95%CI 1.038-1.746), hyperlipidemia (HR=1.504, 95%CI 1.133-1.996), fasting blood glucose (HR=4.189, 95%CI 3.010-5.830), 2-h blood glucose level according to the oral glucose tolerance test (HR=3.005, 95%CI 2.129-4.241), level of glycosylated hemoglobin (HR=3.162, 95%CI 2.283-4.380), and level of γ-glutamyl transferase (HR=1.920, 95%CI 1.385-2.661) were independent risk factors for T2DM. Validation of the nomogram revealed the Concordance Index of the modeling group and validation group to be 0.906 (95%CI 0.888-0.925) and 0.844 (95%CI 0.796-0.892), respectively. Calibration plots showed good calibration in both groups. Conclusion: These data suggest that our nomogram could be a simple and reliable tool for predicting the 4-year risk of developing T2DM in a high-risk Chinese population.

[A meta-analysis of risk factors for multidrug-resistant tuberculosis in China]

Objective: To explore the main risk factors of multidrug-resistant tuberculosis (MDR-TB) in China and to provide evidence-based evidence for MDR-TB preventon and control. Methods: All relevant literatures were searched in thedatabases, such as Pubmed, Web of Science and CNKI, Wanfang, VIP and SinoMed from 2000 to 2021. Quality evaluation and data extraction were carried out, and then a meta-analysis was performed using Stata 16.0 software. Results: A total of 59 literatures (36 cross-sectional and 23 case-control) including 75 793 participants were included in this study, and meta-analysis results showed age (OR=1.27, 95%CI: 1.05-1.54), education level (OR=1.29, 95%CI: 1.02-1.65), positive sputum smear (OR=2.56, 95%CI: 1.09-6.04), pulmonary cavity (OR=1.99, 95%CI: 1.57-2.52), course of disease (OR=4.25, 95%CI: 1.95-9.30), history of tuberculosis treatment (OR=6.42,95%CI:5.40-7.63), treatment interruption (OR=2.81, 95%CI: 1.50-5.29), irregular medication (OR=5.02, 95%CI: 2.95-8.54), adverse drug reactions (OR=4.27, 95%CI: 2.22-8.19), combined chronic obstructive pulmonary disease (COPD) (OR=2.21, 95%CI: 1.45-3.37), tuberculosis exposure history (OR=1.99, 95%CI: 1.36-2.91), smoking history (OR=1.35, 95%CI: 1.09-1.66) and floating population (OR=1.60, 95%CI: 1.04-2.44) were associated with the occurrence of MDR-TB. Conclusions: The high risk groups were farmer, low education level, pulmonary cavity, long course of disease, history of tuberculosis treatment, treatment interruption, irregular medication, adverse drug reaction, co-COPD, contact history of tuberculosis, smoking history, rural residence, and floating population. We should pay attention to high-risk groups, strengthen management and take effective measures such as early screening, knowledge education on tuberculosis, standardized and personalized treatment and whole-course supervision.

[Study of transmissibility of 2019-nCoV Omicron variant in Beijing]

Objective: To evaluate the transmissibility of 2019-nCoV Omicron variant under the current prevention and control strategy in Beijing, and provide evidence for the prevention and control of COVID-19. Methods: The information of 78 Omicron variant infection cases involved in clear transmission chains in Beijing during 7-25 March, 2022 were collected, the incubation period and serial interval of the disease were fitted by using Gamma and Weibull distribution. Markov Chain Monte Carlo approach was used to estimate the time-varying reproduction number (R_t). Results: The median of the incubation period (Q₁, Q₃) of Omicron variant infection was 4.0 (3.0, 6.0) days, and the serial interval was 3.0 (2.0, 5.0) days. The median of the serial interval (Q₁, Q₃) was 2.0 (1.0, 4.0) days in unvaccinated cases and 4.0 (2.0, 6.0) days in vaccinated cases (Z=-2.12, P=0.034), and 2.0 (1.5, 3.0) days in children and 4.0 (2.0, 6.0) days in adults, respectively (Z=-2.02,P=0.044), the differences were significant. The mean of R_t was estimated to be 4.98 (95%CI: 2.22-9.04) for Omicron variant in this epidemic. Conclusion: Omicron variant has stronger transmissibility compared with Delta variant. It is necessary to strengthen the routine prevention and control COVID-19, promote the vaccination and pay close attention to susceptible population, such as children.