Impacts of gene variants on drug effects-the foundation of genotype-guided pharmacologic therapy for long QT syndrome and short QT syndrome

The clinical significance of optimal pharmacotherapy for inherited arrhythmias such as short QT syndrome (SQTS) and long QT syndrome (LQTS) has been increasingly recognised. The advancement of gene technology has opened up new possibilities for identifying genetic variations and investigating the pathophysiological roles and mechanisms of genetic arrhythmias. Numerous variants in various genes have been proven to be causative in genetic arrhythmias. Studies have demonstrated that the effectiveness of certain drugs is specific to the patient or genotype, indicating the important role of gene-variants in drug response. This review aims to summarize the reported data on the impact of different gene-variants on drug response in SQTS and LQTS, as well as discuss the potential mechanisms by which gene-variants alter drug response. These findings may provide valuable information for future studies on the influence of gene variants on drug efficacy and the development of genotype-guided or precision treatment for these diseases.

[Application and advancement of digital teaching materials in teaching epidemiology]

This study aims at examining the application and development of digital teaching materials in the field of epidemiology, encompassing both China and international contexts. The research involved conducting search on websites and literature databases to assess the status of digital teaching materials in epidemiology, nationally and internationally. At present, in China, digital teaching materials used in epidemiology are primarily presented in the form of printed books with added QR codes, providing teaching resources such as videos and exercises. However, issues with the level of interactivity have been identified. In foreign countries, with stronger emphasis placed on personalization, interactivity, and the use of rich media technologies in the digital teaching materials, epidemiologically. Enhanced digitization regarding materials and learning outcomes is achieved through features such as real-time notes, interactive animations, and quizzes. These approaches are considered worth considering for adoption. This study provides valuable insights for the digital transformation of epidemiology education.

Data-driven classification of left atrial morphology and its predictive impact on atrial fibrillation catheter ablation

INTRODUCTION

Various left atrial (LA) anatomical structures are correlated with postablative recurrence for atrial fibrillation (AF) patients. Comprehensively integrating anatomical structures, digitizing them, and implementing in-depth analysis, which may supply new insights, are needed. Thus, we aim to establish an interpretable model to identify AF patients' phenotypes according to LA anatomical morphology, using machine learning techniques.

METHODS AND RESULTS

Five hundred and nine AF patients underwent first ablation treatment in three centers were included and were followed-up for postablative recurrent atrial arrhythmias. Data from 369 patients were regarded as training set, while data from another 140 patients, collected from different centers, were used as validation set. We manually measured 57 morphological parameters on enhanced computed tomography with three-dimensional reconstruction technique and implemented unsupervised learning accordingly. Three morphological groups were identified, with distinct prognosis according to Kaplan-Meier estimator (p < .001). Multivariable Cox model revealed that morphological grouping were independent predictors of 1-year recurrence (Group 1: HR = 3.00, 95% CI: 1.51-5.95, p = .002; Group 2: HR = 4.68, 95% CI: 2.40-9.11, p < .001; Group 3 as reference). Furthermore, external validation consistently demonstrated our findings.

CONCLUSIONS

Our study illustrated the feasibility of employing unsupervised learning for the classification of LA morphology. By utilizing morphological grouping, we can effectively identify individuals at different risks of postablative recurrence and thereby assist in clinical decision-making.

Cyclization-enhanced poly(β-amino ester)s vectors for efficient CRISPR gene editing therapy

Among non-viral gene delivery vectors, poly(β-amino ester)s (PAEs) are one of the most versatile candidates because of their wide monomer availability, high polymer flexibility, and superior gene transfection performance both in vitro and in vivo. Over two decades, PAEs have evolved from linear to highly branched structures, significantly enhancing gene delivery efficacy. Building on the proven efficient sets of monomers in highly branched PAEs (HPAEs), this work introduced a new class of cyclic PAEs (CPAEs) constructed via an A2 + B4 + C2 cyclization synthesis strategy and identified their markedly improved gene transfection capabilities in gene delivery applications. Two sets of cyclic PAEs (CPAEs) with rings of different sizes and topologies were obtained. Their chemical structures were confirmed via two-dimensional nuclear magnetic resonance and the photoluminescence phenomena, and their DNA delivery behaviours were investigated and compared with the HPAE counterparts. In vitro assessments demonstrated that the CPAEs with a macrocyclic architecture (MCPAEs), significantly enhanced DNA intracellular uptake and facilitated efficient gene expression while maintaining perfect biocompatibility. The top-performance MCPAEs have been further employed to deliver a plasmid coding dual single guide RNA-guided CRISPR-Cas9 machinery to delete COL7A1 exon 80 containing the c.6527dupC mutation. In recessive dystrophic epidermolysis bullosa (RDEB) patient-derived epidermal keratinocytes, MCPAEs facilitated the CRISPR plasmid delivery and achieved efficient targeted gene editing in multiple colonies.

Bilobalide Prevents Apoptosis and Improves Cardiac Function in Myocardial Infarction

Myocardial infarction (MI) is an extremely severe cardiovascular disease, which ranks as the leading cause of sudden death worldwide. Studies have proved that cardiac injury following MI can cause cardiomyocyte apoptosis and myocardial fibrosis. Bilobalide (Bilo) from Ginkgo biloba leaves have been widely reported to possess excellent cardioprotective effects. However, concrete roles of Bilo in MI have not been investigated yet. We here designed both in vitro and in vivo experiments to explore the effects of Bilo on MI-induced cardiac injury and the underlying mechanisms of its action. We conducted in vitro experiments using oxygen-glucose deprivation (OGD)-treated H9c2 cells. Cell apoptosis in H9c2 cells was assessed by conducting flow cytometry assay and evaluating apoptosis-related proteins with western blotting. MI mouse model was established by performing left anterior descending artery (LAD) ligation. Cardiac function of MI mice was determined by assessing ejection fraction (EF), fractional shortening (FS), left ventricular end-systolic diameter (LVESD), and left ventricular end-diastolic diameter (LVEDD). Histological changes were analyzed, infarct size and myocardial fibrosis were measured by hematoxylin and eosin (H&E) and Masson staining in cardiac tissues from the mice. The apoptosis of cardiomyocytes in MI mice was assessed by TUNEL staining. Western blotting was applied to detect the effect of Bilo on c-Jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinases (p38 MAPK) signaling both in vitro and in vivo. Bilo inhibited OGD-induced cell apoptosis and lactate dehydrogenase (LDH) release in H9c2 cells. The protein levels of p-JNK and p-p38 were significantly downregulated by Bilo treatment. SB20358 (inhibitor of p38) and SP600125 (inhibitor of JNK) suppressed OGD-induced cell apoptosis as Bilo did. In MI mouse model, Bilo improved the cardiac function and significantly reduced the infarct size and myocardial fibrosis. Bilo inhibited MI-induced cardiomyocytes apoptosis in mice. Bilo suppressed the protein levels of p-JNK and p-p38 in cardiac tissues from MI mice. Bilo alleviated OGD-induced cell apoptosis in H9c2 cells and suppressed MI-induced cardiomyocyte apoptosis and myocardial fibrosis in mice via the inactivation of JNK/p38 MAPK signaling pathways. Thus, Bilo may be an effective anti-MI agent.

Backbone cationized highly branched poly(β-amino ester)s as enhanced delivery vectors in non-viral gene therapy

Gene therapy holds great potential for treating Lung Cystic Fibrosis (CF) which is a fatal hereditary condition arising from mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in dysfunctional CFTR protein. However, the advancement and clinical application of CF gene therapy systems have been hindered due to the absence of a highly efficient delivery vector. In this work, we introduce a new generation of highly branched poly(β-amino ester) (HPAE) gene delivery vectors for CF treatment. Building upon the classical chemical composition of HPAE, a novel backbone cationization strategy was developed to incorporate additional functional amine groups into HPAE without altering their branching degree. By carefully adjusting the type, proportion, and backbone distribution of the added cationic groups, a series of highly effective HPAE gene delivery vectors were successfully constructed for CF disease gene therapy. In vitro assessment results showed that the backbone cationized HPAEs with randomly distributed 10% proportion of 1-(3-aminopropyl)-4-methylpiperazine (E7) amine groups exhibited superior transfection performance than their counterparts. Furthermore, the top-performed backbone cationized HPAEs, when loaded with therapeutic plasmids, successfully reinstated CFTR protein expression in the CFBE41o- disease model, achieving levels 20-23 times higher than that of normal human bronchial epithelial (HBE) cells. Their therapeutic effectiveness significantly surpassed that of the currently advanced commercial vectors, Xfect and Lipofectamine 3000.

Performance of Subcutaneous Implantable Cardioverter Defibrillator (S-ICD) in Chinese Population with Primary Prevention Indications: A Prospective Observational Cohort Study

BACKGROUND International studies have shown that use of a subcutaneous implantable cardioverter defibrillator (S-ICD) could reduce lead-related complications while maintaining adequate defibrillation performance; however, data from the Chinese population or other Asian groups are limited. MATERIAL AND METHODS SCOPE is a prospective, multicenter, observational cohort study. Two hundred patients with primary prevention indication for sudden cardiac death (SCD), who are candidates for S-ICD, will be enrolled. From the same population, another 200 patients who are candidates for transvenous implantable cardioverter defibrillator (TV-ICD) will be enrolled after being matched for age, sex, SCD high-risk etiology (ischemic cardiomyopathy, and non-ischemic cardiomyopathy, ion channel disease, and other) and atrial fibrillation in a 1: 1 ratio with enrolled S-ICD patients. All the patients will be followed for 18 months under standard of care. RESULTS The primary endpoint is proportion of patients free from inappropriate shock (IAS) at 18 months in the S-ICD group. The lower 95% confidence bound of the proportion will be compared with a performance goal of 90.3%, which was derived from the previous meta-analysis. The comparisons between S-ICD and TV-ICD on IAS, appropriate shock, and complications will be used as secondary endpoints without formal assumptions. CONCLUSIONS This is the first prospective multicenter study focusing on the long-term performance of S-ICD in a Chinese population. By comparing with the data derived from international historical studies and a matched TV-ICD group, data from SCOPE will allow for the assessment of S-ICD in the Chinese population in a contemporary real-world implantation level and programming techniques, which will help us to further modify the device implantation and programming protocol in this specific population in the future.

[Evaluation of differences in quality of life in patients with chronic graft-versus-host disease]

Objective: To evaluate the status of, differences in, and factors influencing quality of life (QoL) in patients with chronic graft-versus-host disease (GVHD). Methods: From September 2021 to February 2023, a cross-sectional study of 140 patients with chronic GVHD was conducted at our center. Symptom burden was assessed by the Lee Symptomatology Scale (LSS), and QoL was assessed by the Medical Outcome Study 36-Item Short-Form Health Survey (SF-36) (version 1) and five-level EuroQoL five-dimensional questionnaire (EQ-5D-5L). Results: Data from 140 respondents, including 32 (22.9%) with mild chronic GVHD, 87 (62.1%) with moderate chronic GVHD, and 21 (15.0%) with severe chronic GVHD, were analyzed. Of the respondents, 61.4% were male, and the median transplantation age was 34 (15-68) years. The primary diagnoses were acute myeloid leukemia (50.0%), acute lymphoblastic leukemia (20.0%), and myelodysplastic syndrome (15.0%). The common chronic GVHD-affected organs included the skin in 74 patients (52.9%), the eyes in 57 patients (40.7%), and the liver in 50 patients (35.7%). Among the whole cohort, the eye (20.48±23.75), psychological (16.13±17.00), and oral (13.66±20.55) scores were highest in the LSS group. The physiological function (36.07±11.13), social function (36.10±10.68), and role-emotional functioning (38.36±11.88) scores were lowest in the SF-36 group. The EQ-5D index was 0.764. The total LSS scores for mild, moderate, and severe chronic GVHD were 6.51±6.15, 10.07±5.61, and 20.90±10.09, respectively. The SF-36 physical component scores (PCSs) were 43.12±6.38, 40.73±7.14, and 36.97±6.97, respectively, and the mental component scores (MCSs) were 43.00±8.47, 38.90±9.52, and 28.96±9.63, respectively. The EQ-5D values were 0.810±0.124, 0.762±0.179, and 0.702±0.198, respectively. The multivariate analysis showed that the overall symptom burden (β=-0.517), oral symptom burden (β=-0.456), National Institute of Health (NIH) criteria for the eyes (β=-0.376), and nutrition-related symptom burden (β=-0.211) were significantly negatively correlated with the PCS. The NIH score (β=-0.260) was negatively correlated with the MCS score. Oral symptom burden (β=-0.400), joint/fascia NIH criteria (β=-0.332), number of involved systems (β=-0.253), overall NIH criteria (β=-0.205), and number of immunosuppressants taken (β=-0.171) were significantly negatively correlated with the EQ-5D score (all P<0.05). Medium to strong correlations were found between the EQ-5D score and the SF-36 score (|r|=0.384-0.571, P<0.001). Conclusions: The QoL of patients with chronic GVHD is impaired, and the more severe the disease, the poorer the QoL. Overall symptom burden, severity of eyes, and oral symptom burden were the most important factors affecting QoL.

CRISPR-Cas9-based non-viral gene editing therapy for topical treatment of recessive dystrophic epidermolysis bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is an autosomal monogenic skin disease caused by mutations in COL7A1 gene and lack of functional type VII collagen (C7). Currently, there is no cure for RDEB, and most of the gene therapies under development have been designed as ex vivo strategies because of the shortage of efficient and safe carriers for gene delivery. Herein, we designed, synthesized, and screened a new group of highly branched poly(β amino ester)s (HPAEs) as non-viral carriers for the delivery of plasmids encoding dual single-guide RNA (sgRNA)-guided CRISPR-Cas9 machinery to delete COL7A1 exon 80 containing the c.6527dupC mutation. The selected HPAEs (named PTTA-DATOD) showed robust transfection efficiency, comparable with or surpassing that of leading commercial gene transfection reagents such as Lipofectamine 3000, Xfect, and jetPEI, while maintaining negligible cytotoxicity. Furthermore, CRISPR-Cas9 plasmids delivered by PTTA-DATOD achieved efficient targeted deletion and restored bulk C7 production in RDEB patient keratinocyte polyclones. The non-viral CRISPR-Cas9-based COL7A1 exon deletion approach developed here has great potential to be used as a topical treatment for RDEB patients with mutations in COL7A1 exon 80. Besides, this therapeutic strategy can easily be adapted for mutations in other COL7A1 exons, other epidermolysis bullosa subtypes, and other genetic diseases.

[Application and evaluation of artificial intelligence TPS-assisted cytologic screening system in urine exfoliative cytology]

Objective: To explore the application of manual screening collaborated with the Artificial Intelligence TPS-Assisted Cytologic Screening System in urinary exfoliative cytology and its clinical values. Methods: A total of 3 033 urine exfoliated cytology samples were collected at the Henan People's Hospital, Capital Medical University, Beijing, China. Liquid-based thin-layer cytology was prepared. The slides were manually read under the microscope and digitally presented using a scanner. The intelligent identification and analysis were carried out using an artificial intelligence TPS assisted screening system. The Paris Report Classification System of Urinary Exfoliated Cytology 2022 was used as the evaluation standard. Atypical urothelial cells and even higher grade lesions were considered as positive when evaluating the recognition sensitivity, specificity, and diagnostic accuracy of artificial intelligence-assisted screening systems and human-machine collaborative cytologic screening methods in urine exfoliative cytology. Among the collected cases, there were also 1 100 pathological tissue controls. Results: The accuracy, sensitivity and specificity of the AI-assisted cytologic screening system were 77.18%, 90.79% and 69.49%; those of human-machine coordination method were 92.89%, 99.63% and 89.09%, respectively. Compared with the histopathological results, the accuracy, sensitivity and specificity of manual reading were 79.82%, 74.20% and 95.80%, respectively, while those of AI-assisted cytologic screening system were 93.45%, 93.73% and 92.66%, respectively. The accuracy, sensitivity and specificity of human-machine coordination method were 95.36%, 95.21% and 95.80%, respectively. Both cytological and histological controls showed that human-machine coordination review method had higher diagnostic accuracy and sensitivity, and lower false negative rates. Conclusions: The artificial intelligence TPS assisted cytologic screening system has achieved acceptable accuracy in urine exfoliation cytologic screening. The combination of manual screening and artificial intelligence TPS assisted screening system can effectively improve the sensitivity and accuracy of cytologic screening and reduce the risk of misdiagnosis.

Predictive value of nutritional indices for left atrial thrombus in patients with valvular atrial fibrillation

BACKGROUND

The prognostic nutritional index (PNI) and geriatric nutritional risk index (GNRI) are well known indicators for adverse outcomes in various diseases, but there is no evidence on their association with the risk of left atrial thrombus (LAT) in patients with valvular atrial fibrillation (VAF).

METHODS

A comparative cross-sectional analytical study was conducted on 433 VAF patients. Demographics, clinical characteristics and echocardiographic data were collected and analyzed. Patients were grouped by the presence of LAT detected by transesophageal echocardiography.

RESULTS

LAT were identified in 142 patients (32.79%). The restricted cubic splines showed an L-shaped relationship between PNI and LAT. The dose-response curve flattened out near the horizontal line with OR = 1 at the level of 49.63, indicating the risk of LAT did not decrease if PNI was greater than 49.63. GNRI was negative with the risk of LAT and tended to be protective when greater than 106.78. The best cut-off values of PNI and GNRI calculated by receiver operating characteristics curve to predict LAT were 46.4 (area under these curve [AUC]: 0.600, 95% confidence interval [CI]:0.541-0.658, P = 0.001) and 105.7 (AUC: 0.629, 95% CI:0.574-0.684, P<0.001), respectively. Multivariable logistic regression analysis showed that PNI ≤ 46.4 (odds ratio: 2.457, 95% CI:1.333-4.526, P = 0.004) and GNRI ≤ 105.7 (odds ratio: 2.113, 95% CI:1.076-4.149, P = 0.030) were independent predictors of LAT, respectively.

CONCLUSIONS

Lower nutritional indices (GNRI and PNI) were associated with increased risk for LAT in patients with VAF.

Guanidyl-Rich Poly(β Amino Ester)s for Universal Functional Cytosolic Protein Delivery and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) Cas9 Ribonucleoprotein Based Gene Editing

Protein therapeutics are highly promising for complex disease treatment. However, the lack of ideal delivery vectors impedes their clinical use, especially the carriers for in vivo delivery of functional cytosolic protein. In this study, we modified poly(β amino ester)s (PAEs) with a phenyl guanidine (PG) group to enhance their suitability for cytosolic protein delivery. The effects of the PG group on protein binding, cell internalization, protein function protection, and endo/lysosomal escape were systematically evaluated. Compared to the unmodified PAEs (L3), guanidyl rich PAEs (L3PG) presented superior efficiency of protein binding and protein internalization, mainly via clathrin-mediated endocytosis. In addition, both PAEs showed robust capabilities to deliver cytosolic proteins with different molecular weight (ranging from 30 to 464 kDa) and isoelectric points (ranging from 4.3 to 9), which were significantly improved in comparison with the commercial reagents of PULsin and Pierce Protein Transection Reagent. Moreover, L3PG successfully delivered Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) Cas9 ribonucleoprotein (RNP) into HeLa cells expressing green fluorescent protein (GFP) and achieved more than 80% GFP expression knockout. These results demonstrated that guanidyl modification on PAEs can enhance its capabilities for intracellular delivery of cytosolic functional proteins and CRISPR/Cas9 ribonucleoprotein. The guanidyl-rich PAEs are promising nonviral vectors for functional protein delivery and potential use in protein and nuclease-based gene editing therapies.

Simultaneous Pulsed Field Ablation and Mechanical Closure of Left Atrial Appendage Using a Novel Device

Left atrial appendage (LAA) was shown to harbor triggers and substrate for atrial arrhythmia, electrical isolation of the LAA can be a potential treatment. We describe the use of a novel device that combines electrical isolation of the LAA using pulsed field ablation and mechanical LAA occlusion in a single procedure. (Level of Difficulty: Advanced.).

Evaluation of the Efficacy of Sacubitril/Valsartan on Radiofrequency Ablation in Patients with Hypertension and Persistent Atrial Fibrillation

OBJECTIVE

To evaluate whether the effect of radiofrequency ablation can be improved by using sacubitril/valsartan (S/V) to control blood pressure in hypertensive patients with persistent atrial fibrillation.

METHODS

A total of 63 and 67 hypertension patients with persistent atrial fibrillation were enrolled in an S/V group and ACEI/ARB group, respectively. All patients underwent radiofrequency catheter ablation (RFCA). The blood pressure of the two groups was controlled within the range of 100-140 mmHg (high pressure) and 60-90 mmHg (low pressure). The clinical outcomes of the two groups were observed after 12 months of follow-up.

RESULTS

No significant differences in blood pressure were observed between the S/V and ACEI/ARB groups. In addition, the recurrence rate of atrial fibrillation between the two groups was not different. The left atrial diameter was an independent predictor of recurrence (HR = 1.063, P = 0.008). However, in the heart failure subgroup, the recurrence rate of S/V was significantly lower than that of the ACEI/ARB group (P = 0.005), and Cox regression analysis showed that the recurrence risk of atrial fibrillation of the S/V group was 0.302 lower than that of the ACEI/ARB group. NT-proBNP, LVEF, and LAD were significantly improved in hypertension patients with heart failure when comparing cases before and at the end of follow-up.

CONCLUSIONS

S/V is better than ACEI/ARB in reducing the recurrence of persistent atrial fibrillation in patients with hypertension and heart failure after RFCA.

Nonlinear interaction between double tearing mode and Kelvin-Helmholtz instability with different shear flows

The nonlinear interaction between the double tearing mode (DTM) and Kelvin-Helmholtz (KH) instabilities with different shear flow profiles has been numerically investigated via the use of a compressible magnetohydrodynamics (MHD) model. We focus on KH instabilities in weak and reversed magnetic shear plasmas with strong stabilizing effect of field line bending. Results show that KH instabilities coupled with DTMs occur in these plasmas and the KH mode dominates the instability dynamics, suggesting the crucial role of weak magnetic shear in the formation of high-mode harmonics. For symmetric flows, an asymmetric forced magnetic reconnection configuration is maintained during the growth phase, leading to interlocking of the modes. Additionally, this investigation of the DTM-KH instability interaction contributes to our understanding of the nonlinear reconnection mechanism in the regime of weak and reversed magnetic shear plasmas, which is relevant for astrophysical and fusion studies.

[Evaluation of the efficacy of TIPS in 27 patients with hepatic sinus obstruction syndrome in the near and medium term]

Objective: intrahepatic portocaval shunt (TIPS) in the treatment of hepatic sinusoidal obstruction syndrome (HSOS). Methods: A retrospective analysis was performed on 27 patients with HSOS who were treated with TIPS in our center from July 2018 to July 2020. The changes of portal vein pressure (PVP), portal vein pressure gradient (PPG) and liver function were observed, so as to evaluate the efficacy. Paired t test was adopted to evaluate the quantitative parameters, while χ (2) test was used to analyze qualitative parameters, with P < 0.05 as statistical difference. Results: PVP decreased from (4.41 ± 0.18) kPa before shunt to (2.69 ± 0.11) kPa after shunt (t = 82.41, P < 0.001), PPG decreased from (3.23 ± 0.18) kPa before shunt to (1.46 ± 0.23) kPa after shunt (t = 32.41, P < 0.001). The liver function improved significantly after operation. After 24 months of follow-up, 3 patients developed stent restenosis and recanalized after balloon dilation. Three patients developed hepatic encephalopathy, which was improved after drug treatment. One patient underwent liver transplantation due to liver failure. Conclusion: TIPS is effective in the treatment of HSOS in the short and medium term, and can provide time for liver transplantation patients to wait for liver source.

3D Macrocyclic Structure Boosted Gene Delivery: Multi-Cyclic Poly(β-Amino Ester)s from Step Growth Polymerization

The topological structures of polymers play a critical role in determining their gene delivery efficiency. Exploring novel polymeric structures as gene delivery vectors is thus of great interest. In this work, a new generation of multi-cyclic poly(β-amino ester)s (CPAEs) with unique topology structure was synthesized for the first time via step growth polymerization. Through controlling the occurrence stage of cyclization, three types of CPAEs with rings of different sizes and topologies were obtained. In vitro experiments demonstrated that the CPAEs with macro rings (MCPAEs) significantly boosted the transgene expression comparing to their branched counterparts. Moreover, the MCPAE vector with optimized terminal group efficiently delivered the CRISPR plasmid coding both Staphylococcus aureus Cas9 nuclease and dual guide sgRNAs for gene editing therapy.

[Clinical characteristics and risk factors for bronchoscopic airway mucus hypersecretion in childhood pneumonia infected by different pathogens]

Objective: To investigate the risk factors for airway mucus hypersecretion in childhood pneumonia infected by different pathogens. Method: A retrospective cohort included 968 children who were hospitalized for Mycoplasma pneumoniae pneumonia (MPP), respiratory syncytial virus (RSV) pneumonia, adenovirus pneumonia and underwent bronchoscopy in Respiratory Department of Children's Hospital of Chongqing Medical University from January 2019 to December 2021 was conducted. The children were divided into two groups distinguished by airway mucus secretion according to the airway mucus hypersecretion score which were scored according to the mucus secretion under the bronchoscope. The demographic characteristics, clinical characteristics, laboratory tests and disease severity of the two groups were compared. And the risk factors for the development of airway mucus hypersecretion in two groups were analyzed. Chi square test, Mann-Whithey U test and Fisher exact test were used to analyze the differences between the two groups, and multivariate Logistic regression was used to analyze the influencing factors. Result: There were 559 males and 409 females in the 968 children, with an age of 4.0 (1.4, 6.0) years. Among the 642 children with MPP, 185 cases were in the hypersecretion group and 457 cases were in the non-hypersecretion group. There were 41 cases in the hypersecretion group and 160 cases in the non-hypersecretion group of 201 children with RSV pneumonia. In the 125 children with adenovirus pneumonia, there were 39 cases in the hypersecretion group and 86 cases in the non-hypersecretion group. In these children, the age of children in the hypersecretion group was older than that in the non-hypersecretion group (6.0 (4.0, 7.0) vs. 5.0 (3.0, 7.0) years old, 1.5 (0.5, 3.6) vs. 0.8 (0.4, 1.6) years old, 2.0 (1.2, 4.5) vs. 1.3 (0.8, 2.0) years old, U=35 295.00, 2 492.00, 1 101.00, all P<0.05). Through multivariate Logistic regression analysis it found that increased risk of airway mucus hypersecretion was present in childhood MPP with increase in peripheral blood white blood cell count (OR=3.30, 95%CI 1.51-7.93, P=0.004) or increase in neutrophil ratio (OR=2.24, 95%CI 1.16-4.33, P=0.016) or decrease in lymphocyte count (OR=3.22, 95%CI 1.66-6.31, P<0.001) or decrease in serum albumin (OR=2.00, 95%CI 1.01-3.98, P=0.047). The risk of airway mucus hypersecretion was increased in children with RSV pneumonia combined with elevated peripheral blood eosinophils (OR=3.04, 95%CI 1.02-8.93, P=0.043). Meanwhile, airway mucus hypersecretion was associated with severe pneumonia (OR=2.46, 95%CI 1.03-6.15, P=0.047) in children with RSV pneumonia. Older age was associated with increased risk of airway mucus hypersecretion in children with adenovirus pneumonia (OR=1.02, 95%CI 1.00-1.04, P=0.026). In these children with occurrence of pulmonary rales, wheezes or sputum sounds (OR=3.65, 95%CI 1.22-12.64, P=0.028) had an increased risk of airway mucus hypersecretion. Neutrophils in bronchoalveolar lavage fluid (BALF) demonstrated higher ratio in hypersecretion group from children with MPP (0.65 (0.43, 0.81) vs. 0.59 (0.34, 0.76), U=24 507.00, P<0.01), while the proportion of macrophages in BALF was lower (0.10 (0.05, 0.20) vs. 0.12 (0.06, 0.24), U=33 043.00, P<0.05). Nucleated cell count and neutrophil ratio in BALF were higher in hypersecretion group of children with RSV pneumonia (1 210 (442, 2 100)×10⁶ vs. 490 (210, 1 510)×10⁶/L, 0.43 (0.26, 0.62) vs. 0.30 (0.13, 0.52), U=2 043.00, 2 064.00, all P<0.05). Conclusions: The increase in peripheral blood white blood cell count, neutrophil ratio and decrease in lymphocyte count, serum albumin in children with MPP is related to the development of airway mucus hypersecretion. In children with RSV pneumonia, the abnormal increase of eosinophils in peripheral blood has relationship with hypersecretion. The appearance of lung rale, wheezing, and sputum rale are associated with airway mucus hypersecretion in children with adenovirus pneumonia. In addition, local neutrophil infiltration in the respiratory tract is closely related to the occurrence of airway mucus hypersecretion caused by Mycoplasma pneumoniae and RSV infection.

Artificial Intelligence (AI)-Aided Structure Optimization for Enhanced Gene Delivery: The Effect of the Polymer Component Distribution (PCD)

Gene therapy has emerged as a significant advancement in medicine in recent years. However, the development of effective gene delivery vectors, particularly polymer vectors, remains a significant challenge. Limited understanding of the internal structure of polymer vectors has hindered efforts to enhance their efficiency. This work focuses on investigating the impact of polymer structure on gene delivery, using the well-known polymeric vector poly(β-amino ester) (PAE) as a case study. For the first time, we revealed the distinct characteristics of individual polymer components and their synergistic effects-the appropriate combination of different components within a polymer (high MW and low MW components) on gene delivery. Additionally, artificial intelligence (AI) analysis was employed to decipher the relationship between the polymer component distribution (PCD) and gene transfection performance. Guided by this analysis, a series of highly efficient polymer vectors that outperform current commercial reagents such as jetPEI and Lipo3000 were developed, among which the transfection efficiency of the PAE-B1-based polyplex was approximately 1.5 times that of Lipo3000 and 2 times that of jetPEI in U251 cells.

SHP-1 alleviates atrial fibrosis in atrial fibrillation by modulating STAT3 activation

Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP-1) has a well-established role in myocardial infarction, yet its involvement in atrial fibrosis and atrial fibrillation (AF) has not been elucidated. As cardiac arrhythmias caused by AF are a major global health concern, we investigated whether SHP-1 modulates AF development. The degree of atrial fibrosis was examined using Masson's trichrome staining, and SHP-1 expression in the human atrium was assessed using quantitative polymerase chain reaction (qPCR), immunohistochemistry (IHC), and western blotting (WB). We also examined SHP-1 expression in cardiac tissue from an AF mouse model, as well as in angiotensin II (Ang II)-treated mouse atrial myocytes and fibroblasts. We found that SHP-1 expression was reduced with the aggravation of atrial fibrosis in clinical samples of patients with AF. SHP-1 was also downregulated in the heart tissue of AF mice and Ang II-treated myocytes and fibroblasts, compared with that in the control groups. Next, we demonstrated that SHP-1 overexpression alleviated AF severity in mice by injecting a lentiviral vector into the pericardial space. In Ang II-treated myocytes and fibroblasts, we observed excessive extracellular matrix (ECM) deposition, reactive oxygen species (ROS) generation, and transforming growth factor beta 1 (TGF-β1)/mothers against decapentaplegic homolog 2 (SMAD2) pathway activation, all of which were counteracted by the overexpression of SHP-1. Our WB data showed that STAT3 activation was inversely correlated with SHP-1 expression in samples from patients with AF, AF mice, and Ang II-treated cells. Furthermore, administration of colivelin, a STAT3 agonist, in SHP-1-overexpressing, Ang II-treated myocytes and fibroblasts resulted in higher levels of ECM deposition, ROS generation, and TGF-β1/SMAD2 activation. These findings indicate that SHP-1 regulates AF fibrosis progression by modulating STAT3 activation and is thus a potential treatment target for atrial fibrosis and AF.

Branch Unit Distribution Matters for Gene Delivery

As a key nonviral gene therapy vector, poly(β-amino ester) (PAE) has demonstrated great potential for clinical application after two decades of development. However, even after extensive efforts in structural optimizations, including screening chemical composition, molecular weight (MW), terminal groups, and topology, their DNA delivery efficiency still lags behind that of viral vectors. To break through this bottleneck, in this work, a thorough investigation of highly branched PAEs (HPAEs) was conducted to correlate their fundamental internal structure with their gene transfection performance. We show that an essential structural factor, branch unit distribution (BUD), plays an important role for HPAE transfection capability and that HPAEs with a more uniform distribution of branch units display better transfection efficacy. By optimizing BUD, a high-efficiency HPAE that surpasses well-known commercial reagents (e.g., Lipofectamine 3000 (Lipo3000), jetPEI, and Xfect) can be generated. This work opens an avenue for the structural control and molecular design of high-performance PAE gene delivery vectors.

[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.

MHD instability dynamics and turbulence enhancement towards the plasma disruption at the HL-2A tokamak

The evolutions of MHD instability behaviors and enhancement of both electrostatic and electromagnetic turbulence towards the plasma disruption have been clearly observed in the HL-2A plasmas. Two types of plasma disruptive discharges have been investigated for similar equilibrium parameters: one with a distinct stage of a small central temperature collapse ([Formula: see text] 5-10%) around 1 millisecond before the thermal quench (TQ), while the other without. For both types, the TQ phase is preceded by a rotating 2/1 tearing mode, and it is the development of the cold bubble from the inner region of the 2/1 island O-point along with its inward convection that causes the massive energy loss. In addition, the micro-scale turbulence, including magnetic fluctuations and density fluctuations, increases before the small collapse, and more significantly towards the TQ. Also, temperature fluctuations measured by electron cyclotron emission imaging enhances dramatically at the reconnection site and expand into the island when approaching the small collapse and TQ, and the expansion is more significant close to the TQ. The observed turbulence enhancement near the X-point cannot be fully interpreted by the linear stability analysis by GENE. Evidences suggest that nonlinear effects, such as the reduction of local [Formula: see text] shear and turbulence spreading, may play an important role in governing turbulence enhancement and expansion. These results imply that the turbulence and its interaction with the island facilitate the stochasticity of the magnetic flux and formation of the cold bubble, and hence, the plasma disruption.

A New Optimization Strategy of Highly Branched Poly(β-Amino Ester) for Enhanced Gene Delivery: Removal of Small Molecular Weight Components

Highly branched poly(β-amino ester) (HPAE) has become one of the most promising non-viral gene delivery vector candidates. When compared to other gene delivery vectors, HPAE has a broad molecular weight distribution (MWD). Despite significant efforts to optimize HPAE targeting enhanced gene delivery, the effect of different molecular weight (MW) components on transfection has rarely been studied. In this work, a new structural optimization strategy was proposed targeting enhanced HPAE gene transfection. A series of HPAE with different MW components was obtained through a stepwise precipitation approach and applied to plasmid DNA delivery. It was demonstrated that the removal of small MW components from the original HPAE structure could significantly enhance its transfection performance (e.g., GFP expression increased 7 folds at w/w of 10/1). The universality of this strategy was proven by extending it to varying HPAE systems with different MWs and different branching degrees, where the transfection performance exhibited an even magnitude enhancement after removing small MW portions. This work opened a new avenue for developing high-efficiency HPAE gene delivery vectors and provided new insights into the understanding of the HPAE structure-property relationship, which would facilitate the translation of HPAEs in gene therapy clinical applications.

[Long term results of central hole type posterior chamber intraocular lens in the correction of moderate to high myopia]

Objective: To evaluate the long-term safety,effectiveness,predictability and stability of ICL V4c implantation for moderate to high myopia. Methods: In this retrospective case series study, 95 eyes from 50 patients with moderate to severe myopia who were treated in 2015 underwent central hole type posterior chamber intraocular lens (ICL V4c) implantation at Eye & ENT Hospital of Fudan University. The patients were followed up for a period of five years, during which we assessed various parameters including uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), refractive error, axial length, intraocular pressure, endothelial cell density (ECD), vault, and complications. We used the paired t-test and repeated measures one-way ANOVA in SPSS statistical software to analyze the data. Results: The mean spherical equivalent refraction (SE) decreased significantly from (-12.16±3.04) D preoperatively to (-0.19±0.55) D at one month and (-1.14±0.84) D at five years postoperatively. The safety indices (postoperative CDVA/preoperative CDVA) were 1.24±0.27 and 1.13±0.27, respectively, and the efficacy indices (postoperative UDVA/preoperative CDVA) were 1.14±0.25 and 0.87±0.26 at one month and five years postoperatively. At one month after surgery, 80.00% of the eyes were within ±0.50 D of the expected correction, and 96.84% were within ±1.00 D. There was no significant difference in IOP between preoperative and postoperative measurements. The rate of ECD was 3.87%, and the vault decreased by 106.32 μm at five years postoperatively. Conclusion: ICL V4c implantation is safe and effective with good predictability and stability for long term.

[Gasless submental approach endoscopic removal of thyroglossal cyst]

Objective: To explore the safety and feasibility of gasless submental approach endoscopic removal of thyroglossal cyst. Methods: This work prospectively included the clinical data of 13 patients who underwent the gasless submental approach endoscopic removal of thyroglossal cyst at the Department of Otolaryngology, the First Affiliated Hospital of Chongqing Medical University from August 2021 to February 2022. The operative time, bleeding volumes, postoperative complications, subjective pain levels, satisfaction with incisional scars, neck and facial deformities, and recurrences were prospectively evaluated by visual analogue scale(VAS) score. Results: All of 13 patients were successfully treated using this new technique. The patients had a median age of 38 years, ranging from 24 to 59 years, comprising of 3 males and 10 females. The length of the submental incision was about 3 cm and the median of operation time was 135 minutes. Postoperative complications were minimal. The median volume of blood loss was 10 ml. Surgical site swelling existed in 1 case and dysphagia for more than 1 week occurred in 2 cases. Patients were discharged from the hospital with a median of 3 days after surgery. On a VAS of 0-10 scores, the pain had a median of 2 on the first day after surgery, and the satisfaction with incision scars and neck and facial deformities showed a median of 8 at 6 months after surgery. There were no recurrences during the follow-up period of 9-15 months. Conclusion: Gasless submental approach endoscopic removal of thyroglossal cyst may be a reliable new surgical method that is safe and has cosmetic advantages.

A new nano hyperbranched β-pinene polymer: Controlled synthesis and nonviral gene delivery

Recently, an extensive research effort has been directed toward the improvement of nonviral transfection vectors, such as polymeric materials. The macromolecular structure of polymers has a substantial effect on their transfection efficacy. In this context, the modern advances in polymer production techniques, such as the deactivation-enhanced radical atom transfer polymerization (DE-ATRP), have been fundamental for the synthesis of controlled architecture nanomaterials. In this study, hyperbranched poly(β-pinene)-PDMAEMA-PEGDMA nanometric copolymers were synthesised at high conversion via DE-ATRP using different concentrations of β-pinene for gene delivery applications. The structural characterization and the biological performance of the materials were investigated. The copolymers' molar mass (10,434-16,438 mol l^-1), dispersity, and conversion (90-95%) varied significantly with β-pinene proportion on the polymerizations. The polymer-gene complexes generated (280-110 nm) presented excellent solution stability due to the β-pinene segment on the copolymers. Gene delivery and transfection were highly dependent on the copolymer composition. The copolymers containing the highest β-pinene proportions exhibited the best results with high transfection effectivity. In conclusion, the incorporation of β-pinene in DMAEMA-PEGMA copolymer formulations is a renewable option to improve the materials' branching ratio, polyplex stability, and gene delivery performance without causing cytotoxic effects.

Association of inflammation indices with left atrial thrombus in patients with valvular atrial fibrillation

BACKGROUND

Inflammation has been implicated in the progressive exacerbation of valvular atrial fibrillation (VAF) and thrombogenesis. This study aimed to analyze the association of systemic inflammation as measured by six indices with left atrial thrombus (LAT) in patients with VAF.

METHODS

This comparative cross-sectional analytical study included 434 patients with VAF. Logistic regression analysis was used to assess the predictive value of LAT using six inflammation indices: neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio (MLR), white blood cell-to-mean platelet volume ratio, neutrophil-to-mean platelet volume ratio, systemic immune inflammation index, and systemic inflammation response index. Receiver operating characteristic curves were plotted, and the area under these curves (AUC) were calculated to evaluate the discriminative ability of the indices.

RESULTS

Transesophageal echocardiography revealed LAT in 143 (32.9%) patients. All six indices reflected a positive correlation with C-reactive protein levels. Multivariate logistic analysis revealed that these indices were independent predictors of LAT, and MLR appeared to perform best (odds ratio 12.006 [95% confidence interval (CI) 3.404-42.347]; P < 0.001; AUC 0.639 [95% CI 0.583-0.694]; P < 0.001).

CONCLUSIONS

Selected inflammatory indices were significantly and independently associated with LAT among patients with VAF.

Hyperbranched Poly(β-amino ester)s (HPAEs) Structure Optimisation for Enhanced Gene Delivery: Non-Ideal Termination Elimination

Many polymeric gene delivery nano-vectors with hyperbranched structures have been demonstrated to be superior to their linear counterparts. The higher delivery efficacy is commonly attributed to the abundant terminal groups of branched polymers, which play critical roles in cargo entrapment, material-cell interaction, and endosome escape. Hyperbranched poly(β-amino ester)s (HPAEs) have developed as a class of safe and efficient gene delivery vectors. Although numerous research has been conducted to optimise the HPAE structure for gene delivery, the effect of the secondary amine residue on its backbone monomer, which is considered the non-ideal termination, has never been optimised. In this work, the effect of the non-ideal termination was carefully evaluated. Moreover, a series of HPAEs with only ideal terminations were synthesised by adjusting the backbone synthesis strategy to further explore the merits of hyperbranched structures. The HPAE obtained from modified synthesis methods exhibited more than twice the amounts of the ideal terminal groups compared to the conventional ones, determined by NMR. Their transfection performance enhanced significantly, where the optimal HPAE candidates developed in this study outperformed leading commercial benchmarks for DNA delivery, including Lipofectamine 3000, jetPEI, and jetOPTIMUS.

[Research progress in the treatment of refractory temporal lobe epilepsy based on stereotactic-electroencephalogram]

Temporal lobe epilepsy, with a variety of etiological, symptomatic, electrophysiological characteristics, has the highest incidence among all focal epilepsy, and a high rate of progression to refractory epilepsy. Surgery is an effective treatment, but traditional methods are usually difficult to accurately locate the epileptogenic zone, which may be resolved by stereotactic-electroencephalogram(SEEG) technique. Radiofrequency thermocoagulation and MRI-guided laser interstitial thermal therapy based on SEEG provide a new accurate and minimally invasive choice for refractory epilepsy patients with high surgical risk and difficulty.

[Multidisciplinary regenerative treatment and mechanisms for rescuing a severe calciphylaxis patient with human amnion-derived mesenchymal stem cells]

Calciphylaxis is a rare disease with severe pain and high-mortality due to cutaneous ischemic necrosis and infection that currently lacks proved effective therapies. The occurrence of calciphylaxis in end stage kidney disease (ESKD) patients is known as calcific uremic arteriolopathy (CUA), which is characterized histologically by dermal microvessel calcification, intimal fibroplasia and microthrombosis. Here we innovatively treated a severe CUA patient with human amnion-derived mesenchymal stem cells (hAMSCs). A 34-year-old uremic woman was presented with progressive, painful malodorous ulcers in buttocks and mummified lower limbs. Skin pathological features supported the diagnosis of calciphylaxis. The patient was refractory to conventional multidisciplinary symptomatic therapies. With the approval of our hospital ethics committee, she was treated with hAMSCs including intravenous and local intramuscular injection, and external application of hAMSC culture supernatant to the wound area. During 15-month follow-up, the patient had regeneration of skin and soft tissues, with improved blood biochemical, inflammatory, mineral and bone metabolic indices and immunoregulation effects. After 15-month hAMSC treatment, the score of pain visual analog scale (VAS) decreased from 10 to 0, Bates-Jensen wound assessment tool (BWAT) score decreased from 65 to 13, and wound-quality of life (Wound-QoL) questionnaire score decreased from 68 to 0. We propose that hAMSC treatment is promising for CUA patients. The therapy is potentially involved in the multiple beneficial effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, modulating adverse inflammatory and immunologic responses, promoting re-epithelialization and restoring skin integrity.

Preliminary Study of Genome-Wide Association Identified Novel Susceptibility Genes for Hemorheological Indexes in a Chinese Population

Background

Genome-wide association studies for various hemorheological characteristics have not been reported. We aimed to identify genetic loci associated with hemorheological indexes in a cohort of healthy Chinese Han individuals.

Methods

Genotyping was performed using Applied Biosystems Axiom™ Precision Medicine Diversity Array in 838 individuals, and 6,423,076 single nucleotide polymorphisms were available for genotyping. The relations were examined in an additive genetic model using mixed linear regression and combined with identical by descent matrix.

Results

We identified 38 genetic loci (p < 5 × 10^-6) related to hemorheological traits. In which, LOC102724502-OLIG2 rs28371438 was related to the levels of nd30 (p = 8.58 × 10^-07), nd300 (p = 1.89 × 10^-06), erythrocyte rigidity (p = 1.29 × 10^-06), assigned viscosity (p = 6.20 × 10^-08) and whole blood high cut relative (p = 7.30 × 10^-08). The association of STK32B rs4689231 for nd30 (p = 3.85 × 10^-06) and nd300 (p = 2.94 × 10^-06) and GTSCR1-LINC01541 rs11661911 for erythrocyte rigidity (p = 9.93 × 10^-09) and whole blood high cut relative (p = 2.09 × 10^-07) was found. USP25-MIR99AHG rs1297329 was associated with erythrocyte rigidity (p = 1.81 × 10^-06) and erythrocyte deformation (p = 1.14 × 10^-06). Moreover, the association of TMEM232-SLC25A46 rs3985087 and LINC00470-METTL4 rs9966987 for fibrinogen (p = 1.31 × 10^-06 and p = 4.29 × 10^-07) and plasma viscosity (p = 1.01 × 10^-06 and p = 4.59 × 10^-07) was found.

Conclusion

These findings may represent biological candidates for hemorheological indexes and contribute to hemorheological study.

Enrichment of polystyrene microplastics induces histological damage, oxidative stress, Keap1-Nrf2 signaling pathway-related gene expression in loach juveniles (Paramisgurnus dabryanus)

Polystyrene microplastics (PS-MPs, particle size<5 mm) cause great harm to aquatic organisms. However, their precise effects are not completely understood. In China, placing plastic film at the pond bottom has become an important loach aquaculture mode. In this mode, MPs will affect loach health. This study investigated the enrichment of PS-MPs and its effects on the growth, liver histomorphology, antioxidant enzymes, and Keap1-Nrf2 signaling pathway-related gene expression in loach juveniles (Paramisgurnus dabryanus). The loach juveniles were raised at the concentration of 1000 μg/L fluorescent polystyrene microplastics (PS-MPs) with particle size of 0.5 µm or 5 µm for seven days, the results showed that fluorescent PS-MPs were found to be enriched in liver, intestine, and gill, and the enrichment amount was higher in liver than in gill and intestine (P < 0.05). Furthermore, the enrichment amount of different-sized PS-MPs was different in liver, gill, and intestine. The loach juveniles were cultured for 21 days in the water of the concentration of 100 or 1000 μg/L PS-MPs with particle size of 0.5 µm or 5 µm, the results showed that the survival rate, weight gain rate, and specific growth rate of loach juveniles were significantly reduced. The histological analysis revealed that PS-MPs caused liver damage. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and acetylcholinesterase (AChE) were decreased with the extended exposure to PS-MPs. Generally, the expressions of Nrf2 and Keap1 showed the similar change trend. From 7-14 day, the expression trend of oxidative stressed-related genes was not completely consistent with that of Nrf2 gene, but on day 21, the gene expression trend of oxidative stress-related SOD, CAT, and GSH-PX in the downstream of Keap1-Nrf2 signaling pathway was roughly consistent with that of Nrf2 gene. Basically, the change trends of these three gene expression were similar to those of their corresponding enzyme activities. This study provides theoretical basis for the toxicological effects of PS-MPs on freshwater fish.

Evaluating Common NOS1AP Variants in Patients with Implantable Cardioverter Defibrillators for Secondary Prevention : Evaluating SNPs in NOS1AP

BACKGROUND

Recent research has found that single nucleotide polymorphisms (SNPs) in the nitric oxide synthase 1 adaptor protein (NOS1AP) gene are associated with altered QT intervals and sudden cardiac death (SCD). However, the clinical utility and implications of NOS1AP SNPs remain unclear. Thus, this study aimed to explore the influence of NOS1AP SNPs in patients with implantable cardioverter defibrillator (ICD) for secondary prevention.

METHODS

We conducted a case-control study to evaluate the most studied SNPs in NOS1AP (rs12143842, rs10494366, rs12567209, and rs16847548) in patients with ICD for secondary prevention. Patients were followed for up to 36 months from the time of ICD implantation. ICD interrogation data at 3 and 12 months, including rapid ventricular arrhythmia episodes and appropriate therapies, were then analyzed.  RESULTS: A significant association was observed between rs10494366 and ICD recipients who experienced appropriate therapies. After a mean follow-up time of 31.70 ± 9.15 months, we detected significant differences among the three rs10494366 genotype groups in the distribution of ICD shocks and appropriate therapies, as well as in the correlation of rs10494366 and ICD shocks. According to Kaplan-Meier and Cox regression analyses, patients with the TT genotype had a higher risk of SCD than those with the GG genotype.

CONCLUSIONS

The present study revealed that NOS1AP SNP rs10494366 was associated with appropriate therapies. Specifically, the TT genotype increased ICD shocks and SCD risk in patients with ICD for secondary prevention for the first time.

[Observation of microstructure and vessel density changes in the superficial retinal layer in buried optic disc drusen patients]

Objective: To investigate the changes of the microstructure and vascular density in the superficial retinal layer of buried optic disc drusen (ODD) patients. Methods: Retrospective case-control study. A total of 36 ODD eyes (20 patients) and 26 normal control eyes were recruited in Beijing Union Medical College Hospital from January 2018 to July 2020. Measurement of best corrected visual acuity (BCVA), intraocular pressure, slit lamp, fundus examination and visual field examination were performed. The images and data of spectral domain-optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA) were analyzed and summarized. The differences of nasal retinal nerve fiber layer (RNFL), ganglion cell complex (GCC) thickness and macular superficial vascular density (VD) between ODD patients and normal controls were compared by independent sample t-test or Mann Whitney U test (the right eye was selected in bilateral ODD patients). Results: The 20 ODD patients and 26 normal controls were all female. There was no significant difference in age between the two groups (P>0.05). The BCVA and visual field examination was normal in all ODD patients. The SD-OCT examination showed an oval low signal shadow under the nasal outer nuclear layer of the optic disc, or local accumulation like a medium signal shadow with a clear boundary, and a high signal capsule in ODD patients. The RNFL in the upper nasal side of the ODD group was significantly different from the normal control group [(102.6±19.1) μm vs. (119.0±13.8) μm; t=-2.81; P<0.01]. Compared with normal control group [101.0 (100.0, 102.0) μm], the average GCC thickness in the ODD group [97.0 (89.3, 99.8) μm] was significantly different (U=48.50; P<0.01). The OCTA en-face scan showed that the vascular network in the macular area of the affected eyes was sparser than that of the control eyes. There was significant difference in superficial macular VD beteeen the ODD group (48.5%±2.8%) and the control group (51.0%±2.3%) (t=-2.63; P<0.05). Conclusions: There is thinning in the RNFL upper nasal side and GCC layer of the macular region in buried ODD patients, and the superficial VD of the macular region in buried ODD patients is lower than that in the normal controls.

Recognition and classification of children’s molars based on deep learning

 The detection of molars in this paper is mainly for children around seven years old. The first molars of children in this age group have just erupted. We primarily check whether the teeth need to pit and fissure sealing to protect the teeth from caries. Our dataset comes from dental photos taken by mobile phones. We use these images to train the deep learning model and use the trained deep learning model to detect whether the teeth are healthy. However, this task has enormous challenges. The main difficulties are as follows: first, the teeth are closely arranged, and the individuals are relatively small, so the detection was a bit tricky. Second, the camera’s shooting angles varied greatly, which might cause uneven image quality. Third, the image dataset is relatively small, which might result in the inability to obtain important features when training classification. By analyzing the dataset, we divided the task into two steps to build the model. First, object detection is used to detect the position of the first molar. Second, we classify the tested teeth into three categories. In response to the above problems, both of the two parts of the model are improved. An attention mechanism and a bounding boxes screening mechanism are added to the object detection part. For the classification part, we propose the MCGan model to extend the dataset. The dataset came from children’s dental images collected in a stomatological hospital, and professional dentists annotate the dental images. For molar identification, the accuracy of our model is 98.5%, and the accuracy of tooth classification is 85.6%.

[Effect and mechanism of siRNA targeting α-enolase gene combined with paclitaxel on proliferation, invasion and apoptosis of hepatocellular carcinoma cell]

Objective: To investigate the effect of siRNA targeting inhibition of α-enolase (ENO1) combined with paclitaxel on the proliferation, invasion and apoptosis of hepatocellular carcinoma SK-HEP-1 cell and its mechanism. Methods: siRNA-ENO1 (siRNA-ENO1 group) and siRNA-negative control (siRNA-NC group) were transfected into SK-HEP-1 cells in vitro, the untransfected SK-HEP-1 cells were used as the control group, and the transfection effect was detected by real-time fluorescent quantitative polymerase chain reaction and western blotting. After SK-HEP-1 cells were treated with 0, 2.5, 5, 10, 20 and 40 μg/L paclitaxel for 48 hours, the cell survival rate was measured by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) method and the semi inhibitory concentration of paclitaxel was calculated. SK-HEP-1 cells transfected with siRNA-ENO1 or siRNA-NC were treated with 10 μg/L paclitaxel as paclitaxel+ siRNA-ENO1 group and paclitaxel+ siRNA-NC group. The proliferation, clonogenesis, invasion and apoptosis of siRNA-NC group, siRNA-ENO1 group, paclitaxel+ siRNA-ENO1 group and paclitaxel+ siRNA-NC group were detected by MTT, clonogenesis, Transwell chamber and flow cytometry respectively. The expression levels of the phosphorylation of phosphatidylinositol-3-kinase (p-PI3K), p-protein kinase B (Akt) and proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 9 (MMP-9) and B lymphocytoma-2 gene (Bcl-2) were detected by western blotting. Results: Compared with the control group (1.00±0.00 and 0.69±0.04, respectively), the expression levels of ENO1 mRNA and protein (0.25±0.03 and 0.23±0.02, respectively) in siRNA-ENO1 group decreased significantly (P<0.05), but there were no significant differences in the expression levels of ENO1 mRNA and protein in siRNA-NC group (P>0.05). Compared without treatment group [(100.00±0.00)%, P<0.05], the survival rates of SK-HEP-1 cells treated with 2.5, 5, 10, 20 and 40 μg/L paclitaxel [(88.65±6.46)%, (72.36±6.08)%, (60.48±4.23)%, (38.52±3.56)% and (20.75±2.32)%, respectively] decreased significantly (P<0.05), and the semi inhibitory concentration of paclitaxel was 13.26 μg/L. The cell survival rate and clone formation rate of siRNA-ENO1 group [(68.86±5.12)% and (18.12±2.25)%, respectively] were lower than those of siRNA-NC group [(100.00±0.00)% and (29.65±3.06)%, respectively, P<0.05]. The cell survival rate and clone formation rate of the paclitaxel+ siRNA-ENO1 group [(43.28±2.64)% and (8.72±0.52)%, respectively] were significantly different from those of the paclitaxel+ siRNA-NC group [(61.75±5.06)% and (13.48±2.16)%, respectively, P<0.05] and siRNA-ENO1 groups [(68.86±5.12)% and (18.12±2.25)%, respectively, P<0.05]. Cell invasion number in paclitaxel+ siRNA-ENO1 group (23.64±2.12) was lower than that in siRNA-ENO1 group and paclitaxel+ siRNA-NC group (42.16±2.75 and 37.35±2.42, respectively, P<0.05). The apoptosis rates of paclitaxel+ siRNA-NC group and siRNA-ENO1 group [(17.49±1.35)% and (15.29±1.50)%, respectively] were higher than that of siRNA-NC group [(7.21±0.70)%, P<0.05]. The apoptosis rate in the paclitaxel+ siRNA-ENO1 group [(24.59±2.40)%] was higher than those in the paclitaxel+ siRNA-NC group and siRNA-ENO1 group [(17.49±1.35)% and (15.29±1.50)%, respectively, P<0.05]. The expression levels of ENO1, PI3K/Akt signaling pathway related proteins including p-PI3K and p-Akt and the expression levels of PCNA, MMP-9 and Bcl-2 in siRNA-ENO1 group and paclitaxel+ siRNA-NC group were lower than those in siRNA-NC group (P<0.05). The expression levels of ENO1, p-PI3K, p-Akt, PCNA, MMP-9 and Bcl-2 in paclitaxel+ siRNA-ENO1 group were lower than those in siRNA-ENO1 group or paclitaxel+ siRNA-NC group (P<0.05). Conclusion: siRNA targeting inhibition of ENO1 expression can enhance the inhibitory effect of paclitaxel on proliferation, invasion and apoptosis of SK-HEP-1 cells, and its mechanism may be related to the inhibition of PI3K/AKT signaling pathway.

Development of Minicircle Vectors Encoding COL7A1 Gene with Human Promoters for Non-Viral Gene Therapy for Recessive Dystrophic Epidermolysis Bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare autosomal inherited skin disorder caused by mutations in the COL7A1 gene that encodes type VII collagen (C7). The development of an efficient gene replacement strategy for RDEB is mainly hindered by the lack of vectors able to encapsulate and transfect the large cDNA size of this gene. To address this problem, our group has opted to use polymeric-based non-viral delivery systems and minicircle DNA. With this approach, safety is improved by avoiding the usage of viruses, the absence of bacterial backbone, and the replacement of the control viral cytomegalovirus (CMV) promoter of the gene with human promoters. All the promoters showed impressive C7 expression in RDEB skin cells, with eukaryotic translation elongation factor 1 α (EF1α) promoter producing higher C7 expression levels than CMV following minicircle induction, and COL7A1 tissue-specific promoter (C7P) generating C7 levels similar to normal human epidermal keratinocytes. The improved system developed here has a high potential for use as a non-viral topical treatment to restore C7 in RDEB patients efficiently and safely, and to be adapted to other genetic conditions.

Serum cholesterol efflux capacity is associated with coronary plaque progression in patients with coronary heart disease

Background

Coronary plaque progression is a major risk factor of adverse cardiac events in patients with coronary heart disease (CHD). Emerging evidence showed that attenuated high-density lipoprotein (HDL) function measured by cholesterol efflux capacity (CEC) was associated with development of atherosclerosis independent of HDL cholesterol level. In this study, we sought to investigate whether CEC is a predictor for coronary plaque progression in CHD patients.

Methods

We consecutively enrolled CHD patients from January 2017 to August 2019 in our Hospital who underwent elective percutaneous coronary intervention and had at least one non-target coronary lesion. Follow-up coronary angiography were performed at around 12 months. Fluorescence-labeled cholesterol and J774 macrophages were used to measure the CEC of ApoB-depleted serum sample from all patients. Quantitative coronary angiography (QCA) was performed both at baseline and follow-up to analyze the plaque progression.

Results

A total of 430 CHD patients with 586 non-target coronary lesions were included in the final analysis. During a mean follow-up time of 381.04±59.52 days, patients with decreased CEC presented more severe plaque progression (net luminal loss in highest to lowest CEC quartile: 0.22±0.42mm vs 0.20±0.41mm vs 0.13±0.36mm vs 0.11±0.34mm, p=0.035). In multivariate analysis, baseline CEC was independently associated with coronary plaque progression after adjustment for traditional risk factors including HDL cholesterol and ApoA-I, no matter treated as categorical variable (OR: 0.382 [95% CI 0.180–0.781] for highest to lowest quartile) or continuous variable (OR: 0.522 [95% CI 0.373–0.714] for per SD increase]. Furthermore, CEC demonstrated a better power in predicting coronary plaque progression compared with HDL cholesterol concentration (AUC=0.644 vs 0.514).

Conclusions

This study suggests that HDL function reflected by serum CEC is an independent predictor for coronary plaque progression in CHD patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China, Shanghai Municipal Commission of Health and Family Planning

An Injectable Chitosan-Based Self-Healable Hydrogel System as an Antibacterial Wound Dressing

Due to their biodegradability and biocompatibility, chitosan-based hydrogels have great potential in regenerative medicine, with applications such as bacteriostasis, hemostasis, and wound healing. However, toxicity and high cost are problems that must be solved for chitosan-based hydrogel crosslinking agents such as formaldehyde, glutaraldehyde, and genipin. Therefore, we developed a biocompatible yet cost-effective chitosan-based hydrogel system as a candidate biomaterial to prevent infection during wound healing. The hydrogel was fabricated by crosslinking chitosan with dialdehyde chitosan (CTS-CHO) via dynamic Schiff-base reactions, resulting in a self-healable and injectable system. The rheological properties, degradation profile, and self-healable properties of the chitosan-based hydrogel were evaluated. The excellent antibacterial activity of the hydrogel was validated by a spread plate experiment. The use of Live/Dead assay on HEK 293 cells showed that the hydrogel exhibited excellent biocompatibility. The results demonstrate that the newly designed chitosan-based hydrogel is an excellent antibacterial wound dressing candidate with good biocompatibility.

Synergistic effects ofα-Fe2O3nanoparticles and Fe-doping on gas-sensing performance of NiO nanowires and interface mechanism

High surface area nickel oxide nanowires (NiO NWs), Fe-doped NiO NWs andα-Fe₂O₃/Fe-doped NiO NWs were synthesized with nanocasting pathway, and then the morphology, microstructure and components of all samples were characterized with XRD, TEM, EDS, UV-vis spectra and nitrogen adsorption-desorption isotherms. Owing to the uniform mesoporous template, all samples with the same diameter exhibit the similar mesoporous-structures. The loadedα-Fe₂O₃nanoparticles should exist in mesoporous channels between Fe-doped NiO NWs to form heterogeneous contact at the interface of n-typeα-Fe₂O₃nanoparticles and p-type NiO NWs. The gas-sensing results indicate that Fe-dopant andα-Fe₂O₃-loading both improve the gas-sensing performance of NiO NWs sensors.α-Fe₂O₃/Fe-doped NiO NWs sensors presented the highest response to 100 ppm ethanol gas (55.264) compared with Fe-doped NiO NWs (24.617) and NiO NWs sensors (3.189). The donor Fe-dopant increases the ground state resistance and the absorbed oxygen content in air.α-Fe₂O₃nanoparticles in electron depletion region result in the increasing resistance in ethanol gas and decreasing resistance in air. In this way,α-Fe₂O₃/Fe-doped NiO NWs sensor presents the excellent gas-sensing performance due to the formation of heterogeneous contact at the interface.

Analysis of long non-coding RNA expression profiles in disuse osteoporosis using microarray and bioinformatics

Disuse osteoporosis (DOP) is one of the major consequences of long space flights. DOP also occurs in patients with spinal cord injuries and prolonged bedridden states that can have a severe impact on human health. Bone marrow mesenchymal stem cells (BMSCs) are multipotent stromal cells that play an important role in bone homeostasis. Long non-coding RNAs (lncRNAs) are involved in regulating osteogenic differentiation of BMSCs, and their abnormal expression might lead to the formation of orthopedic diseases. However, the specific mechanism of DOP has not yet been elucidated. All sequencing data were obtained from Gene Expression Omnibus (GEO) datasets. The limma package of R was applied to identify DEmRNAs and DElncRNAs. Pearson correlation coefficients (PCC) between DElncRNADEmRNA expression levels were calculated. Functional annotation was performed for DEmRNAs coexpressed with DElncRNAs. In addition, the Cytohubba plug-in in Cytoscape was applied to determine the top 10 hub genes. Finally, connectivity map (CMap) analysis was used to identify potential therapeutic drugs for DOP. The gene expression data, GSE100930 and GSE17696, were retrieved from the GEO database. A total of 2,212 differentially expressed mRNAs (DEmRNAs) and 22 differentially expressed lncRNAs (DElncRNAs) were obtained. Gene ontology (GO) functional terms, Kyoto Encyclopedia of Genes, and Genomes (KEGG) pathway enrichment analysis reveal 30 significant GO terms and 13 significant pathways. A coding-non-coding gene co-expression (CNC) network was constructed to study the potential role of hub-DElncRNAs and their co-expressed DEmRNAs in DOP. The lncRNAs, GSNAS1, SNHG12, and EPB41LA4A-AS1, were significant in the CNC network and potential regulators of DOP development. Three bioactive compounds (scoulerine, kinetin riboside, dexanabinol) with potential therapeutic significance for DOP were obtained through the Connectivity Map (CMAP) analysis. Our study revealed a new mechanism for a lineage shift of bone marrow mesenchymal stem cells under microgravity, and linked the function of protein-coding mRNAs with ncRNAs, which may contribute to the development of new therapies for DOP.

[Immunogenicity and safety of a boost dose of measles, mumps, and rubella combined vaccine for 4-6 years old children]

Objective: To investigate the immunogenicity and safety of a boost dose of measles, mumps, and rubella combined vaccine (MMR) for children 4 to 6 years old. Methods: Children, aged 4 to 6 years old, had vaccinated with 1 dose of measles and rubella combined vaccine(MR) at the age of 8 months and 1 dose of MMR vaccine at 18-months, were recruited in Shanxi, Inner Mongolia, and Beijing, respectively. All children were assigned into 4, 5 and 6-year-old group. The children who met inclusion and exclusion criteria were vaccinated with 1 dose MMR vaccine, and were collected blood samples before vaccination and 35 to 42 d after the vaccination. During the study period, adverse events were collected at 30 min, 1 d, 2 d, 3 d, 4-12 d, and 13 to 42 days after vaccination. Serum was tested for IgG antibodies against measles, mumps and rubella. Geometric mean concentrations (GMC) of measles, mumps, and rubella antibodies were compared among groups by analysis of variance or non-parametric test. Seropositive rates and adverse event rates were compared among groups by Chi-square test or Fisher exact test. Results: A total of 500 children were included in immunogenicity analysis and 535 children were included in safety analysis. The overall adverse event rate was 20.37%, the most of severity for adverse events was mild. The rates of local and systemic adverse events were 0.37% and 20.00%, respectively. Symptoms of local adverse events were redness. The main systemic adverse events were fever, followed by cough, rash and runny nose. Received a dose of MMR vaccine for booster immunization, the seropositive rates of measles antibody, mumps antibody and rubella antibody were above 99% for all 3 age groups, and there was no significant difference between groups. There were significant differences in mumps antibody GMC among groups (P=0.042), but no significant differences in measles and rubella antibodies GMC. Conclusion: The immunogenicity and safety of a boosted MMR vaccintion in children aged 4, 5 and 6 years were all similar good.

Improved light extraction efficiency of AlGaN deep-ultraviolet light emitting diodes combining Ag-nanodots/Al reflective electrode with highly transparent p-type layer

Enhancement of light extraction efficiency (LEE) of AlGaN-based deep-ultraviolet (DUV) light emitting diodes (LEDs) has been attempted by adopting Ag-nanodots/Al reflective electrodes on a highly transparent complex p-type layer. By thinning the p-GaN to several nm, highly DUV transparent p-type layer is achieved, making it meaningful for the application of reflective electrodes composed of Ag-nanodots and Al film to allow most light emitted upward to be reflected back to the sapphire side. By this approach, the maximum light output power and external quantum efficiency of the DUV-LEDs with optimized Ag nanodots/Al electrodes are severally increased by 52% and 58%, respectively, compared to those with traditional Ni/Au electrodes when the current is below 200 mA.

[Study on the relationship between occupational stress and metabolic syndrome in operating room nursing staff of a third-class A hospital]

Objective: To explore the relationship between occupational stress and metabolic syndrome (MS) in operating room nurses. Methods: In July 2019, 179 nurses in the operating room of a third-class A hospital in Shandong Province were selected as the research objects. The self-designed questionnaire was used to investigate the general situation, and "Nurse Job Stressor Scale" was used to investigate the occupational stress level of nursing staff. The height, weight, waist circumference, blood pressure, fasting blood glucose, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, ischemia-modified albumin, lipoprotein associated phospholipase A2 were measured. The nursing staff were divided into MS group and non-MS group, and the occupational stress levels of the two groups were compared. Chi square test or Fisher test were used to compare the counting data between groups; the measurement data were expressed by Mean±SD, and the comparison between groups was performed with t test. Multiple logistic regression analysis was used to analyze the influencing factors of MS. Results: The overall occupational stress level of nurses in operating room was (450.58±141.77) points, which was significantly lower than the norm score (P<0.05) ; Compared with non-MS group, the overall occupational stress level, work nature, workload and patient related factors in MS group were significantly higher, and the differences were statistically significant (P<0.05) ; The prevalence of abdominal obesity, hypertriglyceridemia, hyperglycemia and hypertension were significantly different among the groups with different occupational stress levels (P<0.05) . After adjusting waist circumference, triglyceride, systolic blood pressure, high density lipoprotein, ischemia modified albumin and lipoprotein associated phospholipase A2, the total score of occupational stress was the risk factor of MS in operating room nurses (P<0.05) . Conclusion: The occupational stress level of nurses in operating room is related to the prevalence of MS.

[Practice guideline for patients with osteoporosis]

In recent years, osteoporosis (OP) has become one of the main diseases affecting the health of middle-aged and elderly people in China, and the prevalence of OP has increased significantly. The clinical diagnosis and treatment guidelines for this disease are also constantly updated. The overall principles speciallyemphasise that doctors and patients need to work together to negotiate the details of the diagnosis and treatment guidelines, in order to improve the OP clinical diagnosis and treatment rate. Therefore, patients' knowledge of the disease, understanding of clinical guidelines, and cooperation with doctors to implement diagnosis and treatment plans are very important. In this study, from the most concerned issues of the patients, we established the OP patient practice guideline working group. 14 recommendations, as the OP patient practice guidelines, are proposed in accordance with the relevant principles of the "World Health Organization guidelines development manual" and the international normative process.