[The value of cardiac MRI in the risk stratification in patients with hypertrophic cardiomyopathy]

Objective: To explore the value of cardiac magnetic resonance imaging (CMR) in the risk stratification of hypertrophic cardiomyopathy (HCM). Methods: HCM patients who underwent CMR examination in Fuwai Hospital between March 2012 and May 2013 were retrospectively enrolled. Baseline clinical and CMR data were collected and patient follow-up was performed using telephone contact and medical record. The primary composite endpoint was sudden cardiac death (SCD) or and equivalent event. The secondary composite endpoint was all-cause death and heart transplant. Patients were divided into SCD and non-SCD groups. Cox regression was used to explore risk factors of adverse events. Receiver operating characteristic (ROC) curve analysis was used to assess the performance and the optimal cut-off of late gadolinium enhancement percentage (LGE%) for the prediction of endpoints. Kaplan-Meier and log-rank tests were used to compare survival differences between groups. Results: A total of 442 patients were enrolled. Mean age was (48.5±12.4) years and 143(32.4%) were female. At (7.6±2.5) years of follow-up, 30 (6.8%) patients met the primary endpoint including 23 SCD and 7 SCD equivalent events, and 36 (8.1%) patients met the secondary endpoint including 33 all-cause death and 3 heart transplant. In multivariate Cox regression, syncope(HR=4.531, 95%CI 2.033-10.099, P<0.001), LGE% (HR=1.075, 95%CI 1.032-1.120, P=0.001) and left ventricular ejection fraction (LVEF) (HR=0.956, 95%CI 0.923-0.991, P=0.013) were independent risk factors for primary endpoint; Age (HR=1.032, 95%CI 1.001-1.064, P=0.046), atrial fibrillation (HR=2.977, 95%CI 1.446-6.131, P=0.003),LGE% (HR=1.075, 95%CI 1.035-1.116, P<0.001) and LVEF (HR=0.968, 95%CI 0.937-1.000, P=0.047) were independent risk factors for secondary endpoint. ROC curve showed the optimal LGE% cut-offs were 5.1% and 5.8% for the prediction of primary and secondary endpoint, respectively. Patients were further divided into LGE%=0, 0<LGE%<5%, 5%≤LGE%<15% and LGE%≥15% groups. There were significant survival differences between these 4 groups whether for primary endpoint or secondary endpoint (all P<0.001) and the accumulated incidence of primary endpoint was 1.2% (2/161), 2.2% (2/89), 10.5% (16/152) and 25.0% (10/40), respectively. Conclusion: LGE is an independent risk factor for SCD events as well as all-cause death and heart transplant. LGE is of important value in the risk stratification in patients with HCM.

[Clinicopathological characteristics and prognosis of patients with small bowel tumors: A single center analysis of 220 cases]

Objective: To analyze the clinicopathological characteristics and prognosis of patients with small bowel tumors. Methods: This was a retrospective, observational study. We collected clinicopathological data of patients with primary jejunal or ileal tumors who had undergone small bowel resection in the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University between January 2012 and September 2017. The inclusion criteria included: (1) older than 18 years; (2) had undergone small bowel resection; (3) primary location at jejunum or ileum; (4) postoperative pathological examination confirmed malignancy or malignant potential; and (5) complete clinicopathological and follow-up data. Patients with a history of previous or other concomitant malignancies and those who had undergone exploratory laparotomy with biopsy but no resection were excluded. The clinicopathological characteristics and prognoses of included patients were analyzed. Results: The study cohort comprised 220 patients with small bowel tumors, 136 of which were classified as gastrointestinal stromal tumors (GISTs), 47 as adenocarcinomas, and 35 as lymphomas. The median follow-up for all patient was 81.0 months (75.9-86.1). GISTs frequently manifested as gastrointestinal bleeding (61.0%, 83/136) and abdominal pain (38.2%, 52/136). In the patients with GISTs, the rates of lymph node and distant metastasis were 0.7% (1/136) and 11.8% (16/136), respectively. The median follow-up time was 81.0 (75.9-86.1) months. The 3-year overall survival (OS) rate was 96.3%. Multivariate Cox regression-analysis results showed that distant metastasis was the only factor associated with OS of patients with GISTs (HR=23.639, 95% CI: 4.564-122.430, P<0.001). The main clinical manifestations of small bowel adenocarcinoma were abdominal pain (85.1%, 40/47), constipation/diarrhea (61.7%, 29/47), and weight loss (61.7%, 29/47). Rates of lymph node and distant metastasis in patients with small bowel adenocarcinoma were 53.2% (25/47) and 23.4% (11/47), respectively. The 3-year OS rate of patients with small bowel adenocarcinoma was 44.7%. Multivariate Cox regression-analysis results showed that distant metastasis (HR=4.018, 95%CI: 2.108-10.331, P<0.001) and adjuvant chemotherapy (HR=0.291, 95% CI: 0.140-0.609, P=0.001) were independently associated with OS of patients with small bowel adenocarcinoma. Small bowel lymphoma frequently manifested as abdominal pain (68.6%, 24/35) and constipation/diarrhea (31.4%, 11/35); 77.1% (27/35) of small bowel lymphomas were of B-cell origin. The 3-year OS rate of patients with small bowel lymphomas was 60.0%. T/NK cell lymphomas (HR= 6.598, 95% CI: 2.172-20.041, P<0.001) and adjuvant chemotherapy (HR=0.119, 95% CI: 0.015-0.925, P=0.042) were independently associated with OS of patients with small bowel lymphoma. Small bowel GISTs have a better prognosis than small intestinal adenocarcinomas (P<0.001) or lymphomas (P<0.001), and small bowel lymphomas have a better prognosis than small bowel adenocarcinomas (P=0.035). Conclusions: The clinical manifestations of small intestinal tumor are non-specific. Small bowel GISTs are relatively indolent and have a good prognosis, whereas adenocarcinomas and lymphomas (especially T/NK-cell lymphomas) are highly malignant and have a poor prognosis. Adjuvant chemotherapy would likely improve the prognosis of patients with small bowel adenocarcinomas or lymphomas.

Structure-based design of a SARS-CoV-2 Omicron-specific inhibitor

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) introduced a relatively large number of mutations, including three mutations in the highly conserved heptad repeat 1 (HR1) region of the spike glycoprotein (S) critical for its membrane fusion activity. We show that one of these mutations, N969K induces a substantial displacement in the structure of the heptad repeat 2 (HR2) backbone in the HR1HR2 postfusion bundle. Due to this mutation, fusion-entry peptide inhibitors based on the Wuhan strain sequence are less efficacious. Here, we report an Omicron-specific peptide inhibitor designed based on the structure of the Omicron HR1HR2 postfusion bundle. Specifically, we inserted an additional residue in HR2 near the Omicron HR1 K969 residue to better accommodate the N969K mutation and relieve the distortion in the structure of the HR1HR2 postfusion bundle it introduced. The designed inhibitor recovers the loss of inhibition activity of the original longHR2_42 peptide with the Wuhan strain sequence against the Omicron variant in both a cell-cell fusion assay and a vesicular stomatitis virus (VSV)-SARS-CoV-2 chimera infection assay, suggesting that a similar approach could be used to combat future variants. From a mechanistic perspective, our work suggests the interactions in the extended region of HR2 may mediate the initial landing of HR2 onto HR1 during the transition of the S protein from the prehairpin intermediate to the postfusion state.

[Establishment and evaluation of a method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples]

OBJECTIVE

To establish the method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples, and to evaluate the efficiency of this method for extraction from urine samples treated with various methods.

METHODS

The S. japonicum SjG28 gene fragment was selected as a target sequence, and the 81 bp short DNA fragment was amplified on the target sequence using PCR assay. Following characterization using sequencing, the short DNA fragment was added into the urine samples as an exogenous short DNA fragment. Primers and probes were designed with SjG28 as a target gene, to establish the real-time fluorescent quantitative PCR (qPCR) assay. The sensitivity of this qPCR assay was evaluated with exogenous short DNA fragments that were diluted at a 1:10 dilution ratio as the DNA template, and the specificity of the qPCR assay was evaluated with the genomic DNA of S. mansoni, S. haematobium, Babesia, Ancyiostoma duodenaie, Cionorchis sinensis, and Paragonimus westermani as DNA templates. Exogenous short DNA fragments were added into artificial and healthy volunteers' urine samples, followed by pH adjustment, centrifugation and concentration, and the efficiency of extracting exogenous short DNA fragments from urine samples was compared with the QIAmp Viral RNA Mini Kit (Qiagen kit) and BIOG cfDNA easy kit (BIOG kit).

RESULTS

An 81 bp small DNA fragment of S. japonicum was successfully prepared, and the lowest detection limit of the established qPCR assay was 100 copies/μL of the 81 bp small DNA fragment of S. japonicum. If the genomic DNA of S. japonicum, S. mansoni, S. haematobium, Babesia, A. duodenaie, C. sinensis, and P. westermani served as DNA templates, the qPCR assay only detected fluorescent signals with S. japonicum genomic DNA as the DNA template. If the pH values of artificial urine samples were adjusted to 5, 6, 7 and 8, the recovery rates were (49.12 ± 2.09)%, (84.52 ± 4.96)%, (89.38 ± 3.32)% and (87.82 ± 3.90)% for extracting the exogenous short DNA fragment of S. japonicum with the Qiagen kit, and were (2.30 ± 0.07)%, (8.11% ± 0.26)%, (13.35 ± 0.61)% and (20.82 ± 0.68)% with the BIOG kit, respectively (t = 38.702, 26.955, 39.042 and 29.571; all P values < 0.01). If the Qiagen kit was used for extracting the exogenous short DNA fragment from artificial urine samples, the lowest recovery rate was seen from urine samples with a pH value of 5 (all P values < 0.05), and there were no significant differences in the recovery rate from urine samples with pH values of 6, 7 and 8 (all P values > 0.05). Following centrifugation of artificial [(64.30 ± 1.00)% vs. (58.87 ± 0.26)%; t = 12.033, P < 0.05] and healthy volunteers' urine samples [(31 165 ± 1 017) copies/μL vs. (28 471 ± 818) copies/μL; t = 23.164, P < 0.05]. In addition, concentration of artificial urine samples with the 10 kDa Centrifugal Filter and concentration of healthy volunteers' urine samples with the 100 kDa Centrifugal Filter were both effective to increase the recovery of the Qiagen kit for extracting the exogenous short DNA fragment of S. japonicum (both P values < 0.01).

CONCLUSIONS

A method for extracting exogenous short DNA fragments of S. japonicum from urine samples has been successfully established, and the Qiagen kit has a high extraction efficiency. Adjustment of urine pH to 6 to 8 and concentration of healthy volunteers' urine samples with the 100 kDa Centrifugal Filter are both effective to increase the efficiency of extracting exogenous short DNA fragments of S. japonicum.

[Publication and citation analyses of Chinese Journal of Schistosomiasis Control from 2011 to 2020]

OBJECTIVE

To investigate the publications and citations of Chinese Journal of Schistosomiasis Control from 2011 to 2020, so as to provide insights into improving the journal quality and impact.

METHODS

All publications were retrieved from 60 issues of 10 volumes of Chinese Journal of Schistosomiasis Control from 2011 to 2020, and publication and citation analyses were performed using a bibliometric method.

RESULTS

A total of 1 867 articles were published in Chinese Journal of Schistosomiasis Control from 2011 to 2020, with the largest number in 2012 (220 publications) and the lowest in 2020 (135 publications), and original article (36.48%), control experience (17.14%) and control study (10.34%) were the three most common article type. The overall proportion of grant-supported articles was 59.08% (1 103/1 867), and the number of grant per article was (2.34±1.58) grants. The mean duration from submission to publication was (173.48±105.84) days per article, and there was a significant difference in the mean duration from submission to publication among years (F = 30.883, P < 0.01). Jiangsu Province (492 publications, 26.35%), Shanghai Municipality (264 publications, 14.14%) and Hubei Province (230 publications, 12.32%) were the three most productive provinces where the first author lived, and disease control and prevention institutions were the predominant affiliations of the first author (67.22%), with Jiangsu Institute of Schistosomiasis Control, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, and Wannan Medical College as the three most productive affiliations. The number of authors was 5.94 authors per publication, and the proportion of co-authored publications was 95.45% in Chinese Journal of Schistosomiasis Control from 2011 to 2020. Journal article was the predominant type of cited (89.97%), and the mean number of citations was (15.70±11.56) citations per publication, with a significant difference in the mean number of citations per publication among years (F = 2.205, P < 0.05). The impact factors of Chinese Journal of Schistosomiasis Control ranged from 0.877 to 1.676 during the period from 2011 to 2020, and the overall Price index was 47.59%.

CONCLUSIONS

Both the academic impact and national transmissibility of Chinese Journal of Schistosomiasis Control appeared a tendency towards a rise from 2011 to 2020. Seeking high-quality contributions, increasing interdisciplinary integration, shortening the duration from submission to publication, expanding the coverage of publication services and enhancing impact are the future priorities of the journal.

[Construction of a human health literacy indicator system for prevention of parasitic diseases based on Delphi method]

OBJECTIVE

To construct a human health literacy indicator system for prevention of parasitic diseases based on Delphi method.

METHODS

Based on literature reviews and expert interviews, a questionnaire was designed and a two-round Delphi consultation was performed. A human health literacy indicator system for prevention of parasitic diseases was constructed according to the deletion criteria and experts' advice.

RESULTS

A total of 14 experts completed the two-round consultation. The second-round authority coefficients were 0.91 to 0.96 for the first-level indicators, 0.87 to 0.97 for the second-level indicators and 0.86 to 0.97 for the third-level indicators. A human health literacy indicator system for prevention of parasitic diseases was constructed with the main framework of basic knowledge and awareness, healthy behaviors, and healthy skills, which contained 3 first-level indicators, 12 second-level indicators and 48 third-level indicators. Among the three first-level indicators, basic knowledge and awareness had the highest weighting coefficient (0.336 5), followed by healthy behaviors (0.334 9), and healthy skills had the lowest weighting coefficient (0.328 6). The three secondary-level indicators with the highest combined weights included awareness of the epidemic status (0.088 2), awareness of the resource of infection (0.085 8) and basic awareness of parasitic diseases (0.085 5).

CONCLUSION

A human health literacy indicator system for prevention of parasitic diseases is preliminarily constructed, which provides insights into the development of health literacy evaluation tools for prevention of parasitic diseases in the new era.

[Recombinant Schistosoma japonicum egg ribonuclease SjCP1412 inhibits the activation of LX-2 hepatic stellate cells in vitro]

OBJECTIVE

To investigate the effect of recombinant Schistosoma japonicum egg ribonuclease SjCP1412 (rSjCP1412) on proliferation, cell cycle, apoptosis and activation of human hepatic stellate cells LX-2 in vitro, and explore the underlying mechanisms.

METHODS

The rSjCP1412 protein was expressed in Escherichia coli BL21 by prokaryotic expression, and the highly purified soluble rSjCP1412 protein was prepared by Ni NTA affinity chromatography and urea gradient refolding dialysis. Yeast RNA was digested using 12.5, 25.0, 50.0 µg rSjCP1412 proteins at 37 °C for 2, 3, 4 h, and the enzymatic products were electrophoresed on 1.5% agarose gel to observe the RNAase activity of rSjCP1412 protein. The proliferation of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was measured using CCK-8 assay, and the apoptosis of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was detected using the Annexin V-FITC/PI double staining, while the percentage of LX-2 cells at G0/G1, S and G2/M phases of cell cycle following stimulation with different doses of rSjCP1412 protein for 48 h was detected by DAPI staining. The type I collagen, type III collagen and α-smooth muscle actin (α-SMA) mRNA expression was quantified using quantitative florescent real-time PCR (qPCR) assay and Western blotting at transcriptional and translational levels in LX-2 cells following stimulation with different doses of rSjCP1412 protein for 48 h, while soluble egg antigen (SEA) served a positive control and PBS without rSjCP1412 protein as a normal control in the above experiments. The expression of collagen I, α-SMA and Smad4 protein was determined using Western blotting in LX-2 cells following stimulation with rSjCP1412 protein, transforming growth factor-β1 (TGF-β1) alone or in combination, to examine the signaling for the effect of rSjCP1412 protein on LX-2 cells.

RESULTS

The rSjCP1412 protein was successfully expressed and the highly purified soluble rSjCP1412 protein was prepared, which had a RNase activity. Compared with the normal group, the survival rates of LX-2 cells significantly decreased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein and SEA for 48 h (F = 22.417 and 20.448, both P values < 0.05). The apoptotic rates of LX-2 cells significantly increased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h (F = 11.350, P < 0.05), and treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h resulted in arrest of LX-2 cells in G0/G1 phase (F = 20.710, P < 0.05). Treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h caused a significant reduction in relative expression levels of collagen I (F = 11.340, P < 0.05), collagen III (F = 456.600, P < 0.05) and α-SMA mRNA (F = 23.100, P < 0.05) in LX-2 cells, and both rSjCP1412 protein and SEA treatment caused a significant reduction in collagen I (F = 1 302.000, P < 0.05), α-SMA (F = 49.750, P < 0.05) and Smad4 protein expression (F = 52.420, P < 0.05) in LX-2 cells. In addition, rSjCP1412 protein treatment inhibited collagen I (F = 66.290, P < 0.05), α-SMA (F = 31.300, P < 0.05) and Smad4 protein expression (F = 27.010, P < 0.05) in LX-2 cells activated by TGF-β1.

CONCLUSIONS

rSjCP1412 protein may induce apoptosis of LX-2 cells and inhibit proliferation, cell cycle and activation of LX-2 cells through down-regulating Smad4 signaling molecules.

Comparing the efficacy of povidone-iodine and normal saline in incisional wound irrigation to prevent superficial surgical site infection: a randomized clinical trial in gastric surgery

BACKGROUND

Prevention of surgical site infection (SSI) after gastrectomy has received increasing attention. Prophylactic incisional wound irrigation has been advocated to reduce SSI, but the choice of solution remains under debate.

AIMS

To compare the efficacies of wound irrigation with normal saline (NS) and povidone-iodine (PVI) for the prevention of SSI after gastrectomy, and to identify the risk factors for SSI.

METHODS

This randomized, single-centre clinical trial included 340 patients with gastric cancer. They were assigned at random into two groups (ratio 1:1) to receive either 0.9% NS or 1.0% PVI solution for incisional irrigation before wound closure. The primary endpoint was postoperative SSI within 30 days of gastrectomy, and the secondary endpoint was the length of hospital stay.

FINDINGS

In total, 333 patients were included in the modified intent-to-treat group, and the SSI rate did not differ significantly between the PVI group (11/167, 6.59%) and the NS group (9/166, 5.42%) [odds ratio (OR) 1.131, 95% confidence interval (CI) 0.459-3.712; P=0.655]. Moreover, the difference between the two groups in terms of length of hospital stay was not significant (P=0.301). Body mass index (BMI) (OR 2.639, 95% CI 1.040-6.694; P=0.041) and postoperative complications (OR 2.565, 95% CI 1.023-6.431; P=0.045) were identified as independent risk factors for SSI.

CONCLUSIONS

NS and PVI had similar efficacy as prophylactic wound irrigation for the prevention of SSI after gastrectomy. The risk of SSI was higher in patients with high BMI or postoperative complications.

[Artificial intelligence facilitates tropical infectious disease control and research]

Since the global pandemic of coronavirus disease 2019 (COVID-19) in late 2019, artificial intelligence technology has shown increasing values in the research and control of tropical infectious diseases. The introduction of artificial intelligence technology has shown remarkable effectiveness to reduce the diagnosis and treatment burdens, reduce missing diagnosis and misdiagnosis, improve the surveillance and forecast ability and enhance the medicine and vaccine development efficiency. This paper summarizes the current applications of artificial intelligence in tropical infectious disease control and research and discusses the important values of artificial intelligence in disease diagnosis and treatment, disease surveillance and forecast, vaccine and drug discovery, medical and public health services and global health governance. However, artificial intelligence technology suffers from problems of single and inaccurate diagnosis, poor disease surveillance and forecast ability in open environments, limited capability of intelligent system services, big data management and model interpretability. Hereby, we propose suggestions with aims to improve multimodal intelligent diagnosis of multiple tropical infectious diseases, emphasize intelligent surveillance and forecast of vectors and high-risk populations in open environments, accelerate the research and development of intelligent management system, strengthen ethical security, big data management and model interpretability.

[Geographical and temporal weighted regression model and its application in epidemiology: a review]

Geographical and temporal weighted regression (GTWR) model is a local regression linear model, which indirectly reflects the spatio-temporal non-stationary characteristics of the study data by calculating the trends for changes in parameters with space and time. Recently, GTWR model has become one of the hot topics in the study on spatio-temporal heterogeneity of diseases. This review summarizes the basic principles and study methods of the GTWR model, and describes the applications of this model in epidemiology.

[Analysis of withdrawal status and influencing factors in patients receiving methadone maintenance treatment in Hubei province]

Objective: To analyze the withdrawal in patients receiving methadone maintenance treatment (MMT) and its related influencing factors in Hubei province. Methods: The patients receiving MMT in clinics in Hubei province were selected from June 2006 to December 2021. The general demographic data, drug abuse history, and MMT information were collected. The survival data of patients with MMT were analyzed by the Kaplan-Meier method, and the Cox proportional hazards model was used for multivariate analysis. Results: A total of 26 716 patients receiving MMT were included in this study, and the gender ratio between men and women was 3.34∶1(20 557∶6 159). The duration of MMT was 0.01-15.72 years, and the median duration was 2.21 (95%CI: 2.16-2.26) years. At the end of the follow-up, the withdrawal proportion was 86.75% (23 175/26 716). MMT's 0-year, 2-year, 4-year, 9-year and 14-year cumulative probabilities appeared as 67.61%, 40.24%, 30.03%, 15.49% and 6.56%, respectively. Results from the Cox proportional hazards regression model showed that the factors of the withdrawal risk were higher in patients receiving MMT, including minority nationality (HR=1.66,95%CI:1.52-1.82), having jobs (HR=1.05, 95%CI:1.01-1.08), no history of compulsory isolation or detoxification (HR=1.04, 95%CI:1.01-1.09) and the enrollment in 2016-2021 (HR=1.46,95%CI:1.35-1.58). The factors of the withdrawal risk were lower in patients receiving MMT, including 60-year-olds or above (HR=0.56,95%CI:0.42-0.75), college degree or above education level (HR=0.83, 95%CI:0.75-0.91), outpatient services of other cities (HR=0.90, 95%CI:0.87-0.93), drug use for 20 years or more (HR=0.72, 95%CI:0.66-0.80), 90 mg or more per daily dosage (HR=0.73,95%CI:0.69-0.78) and the enrollment in 2011-2015 (HR=0.93,95%CI:0.89-0.97). Conclusions: The withdrawal proportions of patients receiving MMT were high in Hubei province. The withdrawal influencing factors were complex. The daily dose was an essential factor that can be intervened under the safe MMT condition, and a higher dose should be appropriately prescribed.

Nanomolar inhibition of SARS-CoV-2 infection by an unmodified peptide targeting the prehairpin intermediate of the spike protein

Variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) challenge currently available coronavirus disease 2019 vaccines and monoclonal antibody therapies through epitope change on the receptor binding domain of the viral spike glycoprotein. Hence, there is a specific urgent need for alternative antivirals that target processes less likely to be affected by mutation, such as the membrane fusion step of viral entry into the host cell. One such antiviral class includes peptide inhibitors, which block formation of the so-called heptad repeat 1 and 2 (HR1HR2) six-helix bundle of the SARS-CoV-2 spike (S) protein and thus interfere with viral membrane fusion. We performed structural studies of the HR1HR2 bundle, revealing an extended, well-folded N-terminal region of HR2 that interacts with the HR1 triple helix. Based on this structure, we designed an extended HR2 peptide that achieves single-digit nanomolar inhibition of SARS-CoV-2 in cell-based and virus-based assays without the need for modifications such as lipidation or chemical stapling. The peptide also strongly inhibits all major SARS-CoV-2 variants to date. This extended peptide is ∼100-fold more potent than all previously published short, unmodified HR2 peptides, and it has a very long inhibition lifetime after washout in virus infection assays, suggesting that it targets a prehairpin intermediate of the SARS-CoV-2 S protein. Together, these results suggest that regions outside the HR2 helical region may offer new opportunities for potent peptide-derived therapeutics for SARS-CoV-2 and its variants, and even more distantly related viruses, and provide further support for the prehairpin intermediate of the S protein.

Infection Characteristics and Physical Prevention Strategy of Panax notoginseng Round Spot Disease Caused by Mycocentrospora acerina

Panax notoginseng round spot disease (PRSD), caused by Mycocentrospora acerina, is the main leaf disease occurring in cultured P. notoginseng. Aiming to find a safe and efficient control method for PRSD, we studied the disease characteristics of PRSD and the optimal growth conditions of M. acerina and evaluated the efficacy of rain-shelter cultivation in PRSD control. Moreover, we described M. acerina based on morphological characterization and molecular analyses (ITS, ACT, LSU, and TEF-1α). The optimum temperature for M. acerina conidial germination was found to be 14 to 22°C. Furthermore, leaf surface wetness for at least 4 h is required for conidial germination, and conidia can successfully infect P. notoginseng when the leaf wetness lasts for more than 8 h. Additionally, rainwater splashing determines the conidial transfection distance, which is less than 2 m. Finally, our study revealed that rain-shelter cultivation is an effective and simple physical prevention strategy to control PRSD, with an average efficacy of up to 100%.

[Three-dimensional volume rendering for dynamic characteristics of secundum atrial septal defect during various phases of the cardiac cycle and the impact on occluder selection]

Objective: To investigate the dynamic change of the secundum atrial septal defect (ASD) throughout the cardiac cycle, and assess its impact on occluder selection. Methods: This study retrospectively analyzed 35 patients with ASD who received electrocardiogram-gated coronary CT angiography (CCTA) throughout the cardiac cycle as well as interventional closure therapy in Fuwai Hospital from December 2016 to December 2019. The raw data were reconstructed into 20 phasic images of RR intervals (RRI) ranging from 0 to 95% in an increment of 5% and transmitted to a workstation for postprocessing. For each phase image, CT virtual endoscopy reconstruction technique (CTVE) was used to provide views of ASD. Axial sequence assisted CT volumetric measurement (CTAS) was used to calculate the maximum dimensions in axial planes (D_a) and in superior-inferior direction (D_b). Using a formula for converting circumference to diameter, the equivalent circle dimensions were calculated (D_e, D_e=minor axis+2 (major axis-minor axis)/3). Taking the data of 75% RRI phase, the patients were divided into D_a75%RRI≥D_b75%RRI group and D_a75%RRI<D_b75%RR group. According to the postoperative chest X-ray, the waist diameter of the occluder in the left anterior oblique plain film was measured, and its correction value (CR-POD_laoc) was calculated with the correction formula. Scatter plots of the changes of the mean values of D_a, D_b and D_e with the cardiac cycle were presented. The change and ratio of measured values of D_a and D_e at 35% and 75% RRI was calculated. The ratio of D_e change to D_a change in D_a75%RRI≥D_b75%RRI group and D_a75%RRI<D_b75%RR group was calculated, respectively, and compared between groups. Pearson correlation analysis was used to explore the correlation between CR-POD_laoc and D_e35%RRI and D_e75%RRI. Results: A total of 35 patients, aged (42.7±15.0) years, including 10 males, were included. Among 35 patients, 8 cases were divided into group D_a75%RRI≥D_b75%RRI and 27 cases into group D_a75%RRI<D_b75%RRI. Both D_a and D_b regularly changed at each phase throughout the cardiac cycle. The D_a changed significantly, with a maximum at phase of 35%-45% of RRI, and a minimum between phases of 90% and 0 of RRI. While the D_b showed insignificant changes during phases of 10%-90% RRI, and increased at 0-10% of RRI, then reduced in the remaining phases. The change of D_a was (6.35±2.46) mm, and the ratio of D_a values at 35% and 75% RRI was 0.77±0.08. The change of D_e was (2.28±1.32) mm, and the ratio of D_e at 35% and 75% RRI was 0.93±0.05. The ratio of D_e change to D_a change in the D_a75%RRI≥D_b75%RRI group was 0.67±0.13; while the ratio was 0.34±0.05 in D_a75%RRI<D_b75%RR group, and there was significant difference between the two groups (P=0.02). CR-POD_laoc was positively correlated with D_{e35% RRI} (r=0.99, P<0.001) and D_{e75% RRI} (r=0.98, P<0.001). Conclusions: Most secundum ASDs show oval shape with D_b>D_a. D_b is basically constant while D_a changes significantly during cardiac cycle (10%-90% RRI). Nonetheless, both values peak and maintain the maximum status at end-systolic phase (35%-45% RRI). For patients with huge ASD, occluder selection should be based on the D_e at 35% RRI phase, which is helpful for the successful intervention.

[Predictive value of serum HBV RNA for therapeutic effect of entecavir in patients with chronic hepatitis B]

OBJECTIVE

To investigate the value of HBV RNA for predicting the therapeutic effect of long-term entecavir (ETV) antiviral therapy in patients with chronic hepatitis B (CHB).

METHODS

Serum samples were collected from 59 CHB patients treated with ETV for 96 or 108 months. HBV RNA levels, HBV DNA levels, and serological marker (HBeAg) levels were measured at baseline and 3, 6, 9, 12, 36, 72, and 96 (or 108) months during the therapy.

RESULTS

Although HBV RNA level decreased after 12 and 36 months of ETV antiviral therapy, no significance changes occurred in HBV RNA negative conversion rate (P>0.05). After 72 months of treatment or longer, 33 patients had HBV RNA levels lower than 100 copies/mL, and among them 29 patients had HBV RNA levels lower than the detection limit, and HBV RNA negative conversion rate was statistically significant (P < 0.05). A lower HBV RNA level was associated with a higher HBeAg negative conversion rate (P < 0.05). Age and HBV RNA level were positively correlated with HBeAg negative conversion rate (P < 0.05).

CONCLUSION

Prolonged ETV antiviral therapy results in better clearance of HBV RNA and a higher negative conversion rate in CHB patients. The length of antiviral therapy and age are positively correlated with the negative conversion rate of HBV RNA, and earlier administration of the antiviral treatment achieves better therapeutic effect. Serum HBV RNA level can be used as an indicator for predicting conversion to negative HBeAg in CHB patients receiving ETV therapy.