m6A-Mediated Upregulation of Imprinted in Prader-Willi Syndrome Induces Aberrant Apical-Basal Polarization and Oxidative Damage in RPE Cells.

Purpose: To reveal the clinical significance, pathological involvement and molecular mechanism of imprinted in Prader-Willi syndrome (IPW) in RPE anomalies that contribute to AMD. Methods: IPW expression under pathological conditions were detected by microarrays and qPCR assays. In vitro cultured fetal RPE cells were used to study the pathogenicity induced by IPW overexpression and to analyze its upstream and downstream regulatory networks. Results: We showed that IPW is upregulated in the macular RPE-choroid tissue of dry AMD patients and in fetal RPE cells under oxidative stress, inflammation and dedifferentiation. IPW overexpression in fetal RPE cells induced aberrant apical-basal polarization as shown by dysregulated polarized markers, disrupted tight and adherens junctions, and inhibited phagocytosis. IPW upregulation was also associated with RPE oxidative damages, as demonstrated by intracellular accumulation of reactive oxygen species, reduced cell proliferation, and accelerated cell apoptosis. Mechanically, N6-methyladenosine level of the IPW transcript regulated its stability with YTHDC1 as the reader. IPW mediated RPE features by suppressing MEG3 expression to sequester its inhibition on the AKT serine-threonine kinase (AKT)/mammalian target of rapamycin (mTOR) pathway. We also noticed that the mTOR inhibitor rapamycin suppresses the AKT/mTOR pathway to alleviate the IPW-induced RPE anomalies. Conclusions: We revealed that IPW overexpression in RPE induces aberrant apical-basal polarization and oxidative damages, thus contributing to AMD progression. We also annotated the upstream and downstream regulatory networks of IPW in RPE. Our findings shed new light on the molecular mechanisms of RPE dysfunctions, and indicate that IPW blockers may be a promising option to treat RPE abnormalities in AMD.

Lactylation-driven FTO targets CDK2 to aggravate microvascular anomalies in diabetic retinopathy.

Diabetic retinopathy (DR) is a leading cause of irreversible vision loss in working-age populations. Fat mass and obesity-associated protein (FTO) is an N6-methyladenosine (m6A) demethylase that demethylates RNAs involved in energy homeostasis, though its influence on DR is not well studied. Herein, we detected elevated FTO expression in vitreous fibrovascular membranes of patients with proliferative DR. FTO promoted cell cycle progression and tip cell formation of endothelial cells (ECs) to facilitate angiogenesis in vitro, in mice, and in zebrafish. FTO also regulated EC-pericyte crosstalk to trigger diabetic microvascular leakage, and mediated EC-microglia interactions to induce retinal inflammation and neurodegeneration in vivo and in vitro. Mechanistically, FTO affected EC features via modulating CDK2 mRNA stability in an m6A-YTHDF2-dependent manner. FTO up-regulation under diabetic conditions was driven by lactate-mediated histone lactylation. FB23-2, an inhibitor to FTO's m6A demethylase activity, suppressed angiogenic phenotypes in vitro. To allow for systemic administration, we developed a nanoplatform encapsulating FB23-2 and confirmed its targeting and therapeutic efficiency in mice. Collectively, our study demonstrates that FTO is important for EC function and retinal homeostasis in DR, and warrants further investigation as a therapeutic target for DR patients.

ALKBH5 causes retinal pigment epithelium anomalies and choroidal neovascularization in age-related macular degeneration via the AKT/mTOR pathway.

Retinal pigment epithelium (RPE) dysfunction and choroidal neovascularization (CNV) are predominant features of age-related macular degeneration (AMD), with an unclear mechanism. Herein, we show that RNA demethylase α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) is up-regulated in AMD. In RPE cells, ALKBH5 overexpression associates with depolarization, oxidative stress, disturbed autophagy, irregular lipid homeostasis, and elevated VEGF-A secretion, which subsequently promotes proliferation, migration, and tube formation of vascular endothelial cells. Consistently, ALKBH5 overexpression in mice RPE correlates with various pathological phenotypes, including visual impairments, RPE anomalies, choroidal neovascularization (CNV), and interrupted retinal homeostasis. Mechanistically, ALKBH5 regulates retinal features through its demethylation activity. It targets PIK3C2B and regulates the AKT/mTOR signaling pathway with YTHDF2 as the N6-methyladenosine reader. IOX1, an ALKBH5 inhibitor, suppresses hypoxia-induced RPE dysfunction and CNV progression. Collectively, we demonstrate that ALKBH5 induces RPE dysfunction and CNV progression in AMD via PIK3C2B-mediated activation of the AKT/mTOR pathway. Pharmacological inhibitors of ALKBH5, like IOX1, are promising therapeutic options for AMD.

Heterozygous Seryl-tRNA Synthetase 1 Variants Cause Charcot-Marie-Tooth Disease.

OBJECTIVE: Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT. METHODS: Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays. RESULTS: Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation. INTERPRETATION: Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.

Reyanning Mixture on Asymptomatic or Mild SARS-CoV-2 Infection in Children and Adolescents: A Randomized Controlled Trial / 中国结合医学杂志

OBJECTIVE@#To assess the effect and safety of Reyanning Mixture (RYN) in treating asymptomatic or mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children and adolescents.@*METHODS@#This is a prospective, open-label, randomized controlled trial. Patients aged 1-17 years and diagnosed with asymptomatic or mild coronavirus disease-2019 (COVID-19) were assigned to an intervention group (RYN plus standard care) and a control group (standard care) according to a randomization list. The primary outcomes were SARS-CoV-2 negative conversion time. Secondary outcomes included negative conversion rate on days 3 and 7, hospital length of stay, symptom relief rate, new-onset symptoms of asymptomatic infected patients, and progressive disease rate. The cycle threshold (Ct) values of ORF1ab or N genes were also tested.@*RESULTS@#A total of 214 patients in the intervention group and 217 in the control group were analyzed. The SARS-CoV-2 negative conversion time was significantly shortened in the intervention group [5 days (interquartile range (IQR): 5-6) vs. 7 days (IQR: 6-7), P<0.01]. By days 3 and 7, the negative conversion rates were significantly higher in the intervention group (day 3: 32.7% vs. 21.2%, P=0.007; day 7: 75.2% vs. 60.8%, P=0.001). Ct values significantly increase on day 2 [ORF1ab gene: 35.62 (IQR: 29.17-45.00) vs. 34.22 (IQR: 28.41-39.41), P=0.03; N gene: 34.97 (IQR: 28.50-45.00) vs. 33.51 (IQR: 27.70-38.25), P=0.024] and day 3 [ORF1ab gene: 38.00 (IQR: 32.72-45.00) vs. 35.81 (IQR: 29.96-45.00), P=0.003; N gene: 37.16 (IQR: 32.01-45.00) vs. 35.26 (IQR: 29.09-45.00), P=0.01]. No significant difference was found in hospital length of stay between the two groups (P>0.05). Symptoms of cough were significantly improved (82.2% vs. 70.0%, P=0.02) and wheezing was significantly reduced (0.7% vs. 12.9%, P<0.01) in the intervention group compared with the control group. During the trial, no disease progression or serious adverse events were reported.@*CONCLUSION@#Adding RYN to standard care may be a safe and effective treatment for children with asymptomatic and mild SARS-CoV-2 infection. (Registration No. ChiCTR2200060292).

Viral selection pressure and CD4+T cell epitope in HLA-DRB1 * 11:01 of HCV infected patients / 中国输血杂志

【Objective】 HLA-DRB1 * 11:01, as a class HLA-Ⅱ gene, was reported to be associated with spontaneous clearance of HCV in Han and Li population. Our study was to investigate the effects of viral selection pressure and CD4+T cell epitope on the natural outcome of HCV infection in HLA-DRB1 * 11:01 positive infected patients. 【Methods】 The positive selection sites and population growth of E1E2 and NS3 genes of common HCV 6a in HLA-DRB1 * 11:01 positive and negative groups in Guangdong were respectively analyzed. The peptide library covering the conserved regions of common HCV genotypes was used to stimulate HCV spontaneous clearance group and chronic infection group using ELISPOT method. Reactive peptides were obtained according to the number of spot-forming cells per well and the frequency of occurrence in different groups. 【Results】 The positive selection sites (PSSs) of E1E2 and NS3 of common HCV 6a in HLA-DRB1 * 11:01 negative group were greater than those in HLA-DRB1 * 11:01 positive group. Furthermore, the number of PPSs in CD4+T cell peptide in HLA-DRB1 * 11:01 negative group were also greater than those in HLA-DRB1 * 11:01 positive group; Both groups of HCV 6a had a population growth in Guangdong, and the expansion trend of HLA-DRB1 * 11:01 negative group was significantly higher than that of HLA-DRB1 * 11 :01 positive group. Compared to HCV chronic infection group, the response rate of HCV spontaneous clearance group to five peptides (C-52 E2691-707, C-119 NS31545-1560, C-134 NS4A1669-1684, C-154 NS4B1912-1927, C-159 NS4B1929-1944) was higher. However, the HCV chronic infection group showed a higher response rate to two of the peptides(C-111 NS31497-1512, C-130 NS31650-1665). When HLA-DRB1 * 11:01 typing was considered, there was no significant difference in HCV-specific immune response generated by PBMCs between HLA-DRB1 * 11:01 positive and HLA-DRB1 * 11:01 negative groups. 【Conclusion】 This study revealed the relationship between viral selection pressure of HLA-DRB1 * 11:01 HCV infected persons and CD4+T cell antigen epitopes. At the same time, CD4+ T cell antigen epitopes of HCV pan-genotype were obtained, providing basic data for the development of T cell vaccine suitable for HCV pan-genotype.

Detection and analysis of antibodies against SARS-CoV-2 in blood donors at different periods in Guangzhou / 中国输血杂志

【Objective】 To detect the anti-SARS-CoV-2 antibody levels in blood donors in Guangzhou, so as to provide laboratory data support for the collection and clinical use of convalescent plasma. 【Methods】 Anti-SARS-CoV-2 antibodies were measured by ELISA in qualified donors. Among them, 326 donors who gave blood in February 2023 were tested for IgG antibodies, 444 donors were tested for neutralizing antibodies. In July 2023, 398 donors were tested for IgG and IgM. 【Results】 399 of 724 blood samples diluted with normal saline (1∶160) were IgG reactive, with a reactive rate of 55.11%. Chi-square test showed that there was a significant difference in the reactive rate of IgG among samples collected at different times (25.46% in February vs 79.40% in July, χ2=210.74, P<0.01, 95%CI: 7.97, 15.98), but there was no significant difference in the reactive rate between different genders and different age groups. IgM was detected in 5 of 398 blood samples, with a reactive rate of 1.26%. The IgG test results of these five blood donors were all reactive, whereas the nucleic acid test results were negative. Neutralizing antibody was detected in 440 of 444 blood samples, with a reactive rate of 99.10%, and 71.59% of the reactive donors had a neutralizing antibody level of 10 μg/mL or more. 【Conclusion】 Blood donors in Guangzhou have a high level of SARS-CoV-2 antibody, which is sufficient to provide convalescent plasma for clinical treatment.

Accuracy of Mean Value of Central Venous Pressure from Monitor Digital Display: Influence of Amplitude of Central Venous Pressure during Respiration / 中国医学科学杂志(英文版)

Background A simple measurement of central venous pressure (CVP)-mean by the digital monitor display has become increasingly popular. However, the agreement between CVP-mean and CVP-end (a standard method of CVP measurement by analyzing the waveform at end-expiration) is not well determined. This study was designed to identify the relationship between CVP-mean and CVP-end in critically ill patients and to introduce a new parameter of CVP amplitude (ΔCVP= CVPmax - CVPmin) during the respiratory period to identify the agreement/disagreement between CVP-mean and CVP-end.Methods In total, 291 patients were included in the study. CVP-mean and CVP-end were obtained simultaneously from each patient. CVP measurement difference (|CVP-mean - CVP-end|) was defined as the difference between CVP-mean and CVP-end. The ΔCVP was calculated as the difference between the peak (CVPmax) and the nadir value (CVPmin) during the respiratory cycle, which was automatically recorded on the monitor screen. Subjects with |CVP-mean - CVP-end|≥ 2 mmHg were divided into the inconsistent group, while subjects with |CVP-mean - CVP-end| < 2 mmHg were divided into the consistent group.Results ΔCVP was significantly higher in the inconsistent group [7.17(2.77) vs.5.24(2.18), P<0.001] than that in the consistent group. There was a significantly positive relationship between ΔCVP and |CVP-mean - CVP-end| (r=0.283, P <0.0001). Bland-Altman plot showed the bias was -0.61 mmHg with a wide 95% limit of agreement (-3.34, 2.10) of CVP-end and CVP-mean. The area under the receiver operating characteristic curves (AUC) of ΔCVP for predicting |CVP-mean - CVP-end| ≥ 2 mmHg was 0.709. With a high diagnostic specificity, using ΔCVP<3 to detect |CVP-mean - CVP-end| lower than 2mmHg (consistent measurement) resulted in a sensitivity of 22.37% and a specificity of 93.06%. Using ΔCVP>8 to detect |CVP-mean - CVP-end| >8 mmHg (inconsistent measurement) resulted in a sensitivity of 31.94% and a specificity of 91.32%.Conclusions CVP-end and CVP-mean have statistical discrepancies in specific clinical scenarios. ΔCVP during the respiratory period is related to the variation of the two CVP methods. A high ΔCVP indicates a poor agreement between these two methods, whereas a low ΔCVP indicates a good agreement between these two methods.

Efficacy and Safety of Huashi Baidu Granules in Treating Patients with SARS-CoV-2 Omicron Variant: A Single-Center Retrospective Cohort Study / 中国结合医学杂志

OBJECTIVE@#To evaluate the efficacy and safety of Huashi Baidu Granules (HSBD) in treating patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant.@*METHODS@#A single-center retrospective cohort study was conducted during COVID-19 Omicron epidemic in the Mobile Cabin Hospital of Shanghai New International Expo Center from April 1st to May 23rd, 2022. All COVID-19 patients with asymptomatic or mild infection were assigned to the treatment group (HSBD users) and the control group (non-HSBD users). After propensity score matching in a 1:1 ratio, 496 HSBD users of treatment group were matched by propensity score to 496 non-HSBD users. Patients in the treatment group were administrated HSBD (5 g/bag) orally for 1 bag twice a day for 7 consecutive days. Patients in the control group received standard care and routine treatment. The primary outcomes were the negative conversion time of nucleic acid and negative conversion rate at day 7. Secondary outcomes included the hospitalized days, the time of the first nucleic acid negative conversion, and new-onset symptoms in asymptomatic patients. Adverse events (AEs) that occurred during the study were recorded. Further subgroup analysis was conducted in vaccinated (378 HSBD users and 390 non-HSBD users) and unvaccinated patients (118 HSBD users and 106 non-HSBD users).@*RESULTS@#The median negative conversion time of nucleic acid in the treatment group was significantly shortened than the control group [3 days (IQR: 2-5 days) vs. 5 days (IQR: 4-6 days); P<0.01]. The negative conversion rate of nucleic acid in the treatment group were significantly higher than those in the control group at day 7 (91.73% vs. 86.90%, P=0.014). Compared with the control group, the hospitalized days in the treatment group were significantly reduced [10 days (IQR: 8-11 days) vs. 11 days (IQR: 10.25-12 days); P<0.01]. The time of the first nucleic acid negative conversion had significant differences between the treatment and control groups [3 days (IQR: 2-4 days) vs. 5 days (IQR: 4-6 days); P<0.01]. The incidence of new-onset symptoms including cough, pharyngalgia, expectoration and fever in the treatment group were lower than the control group (P<0.05 or P<0.01). In the vaccinated patients, the median negative conversion time and hospitalized days were significantly shorter than the control group after HSDB treatment [3 days (IQR: 2-5 days) vs. 5 days (IQR: 4-6 days), P<0.01; 10 days (IQR: 8-11 days) vs. 11 days (IQR: 10-12 days), P<0.01]. In the unvaccinated patients, HSBD treatment efficiently shorten the median negative conversion time and hospitalized days [4 days (IQR: 2-6 days) vs. 5 days (IQR: 4-7 days), P<0.01; 10.5 days (IQR: 8.75-11 days) vs. 11.0 days (IQR: 10.75-13 days); P<0.01]. No serious AEs were reported during the study.@*CONCLUSION@#HSBD treatment significantly shortened the negative conversion time of nuclear acid, the length of hospitalization, and the time of the first nucleic acid negative conversion in patients infected with SARS-COV-2 Omicron variant (Trial registry No. ChiCTR2200060472).

m6A modification of circSPECC1 suppresses RPE oxidative damage and maintains retinal homeostasis.

Age-related macular degeneration (AMD) is a leading cause of irreversible vision loss in the elderly population with unclear pathogenic mechanism. Herein, we detect downregulated circSPECC1 expression in retinal pigment epithelium (RPE) of AMD patients. In RPE cells, circSPECC1 insufficiency leads to oxidative stress-induced ferroptosis, depolarization, and irregular lipid metabolism. Consistently, in mice, circSPECC1 deficiency induces visual impairments and RPE anomalies and interrupts retinal homeostasis. Mechanically, nuclear export of circSPECC1 transcript depends on its N6-methyladenosine (m6A) level with YTHDC1 as the reader. CircSPECC1 directly sponges miR-145-5p to block its interaction with CDKN1A. Overexpressing miR-145-5p aggravates RPE dysfunctions, mimicking circSPECC1 silencing effects. Retinal phenotypes induced by circSPECC1 insufficiency are alleviated by miR-145-5p inhibition and are aggravated by miR-145-5p overexpression. Collectively, circSPECC1, mediated by m6A modification and sponging miR-145-5p, resists oxidative stress injuries and maintains lipid metabolism in RPE. Pharmacological supplementation of circSPECC1 is a promising therapeutic option for atrophic retinopathies like AMD.

The Role of N6-Methyladenosine Modification in Microvascular Dysfunction.

Microvascular dysfunction (MVD) has long plagued the medical field despite improvements in its prevention, diagnosis, and intervention. Microvascular lesions from MVD increase with age and further lead to impaired microcirculation, target organ dysfunction, and a mass of microvascular complications, thus contributing to a heavy medical burden and rising disability rates. An up-to-date understanding of molecular mechanisms underlying MVD will facilitate discoveries of more effective therapeutic strategies. Recent advances in epigenetics have revealed that RNA methylation, an epigenetic modification, has a pivotal role in vascular events. The N6-methylation of adenosine (m6A) modification is the most prevalent internal RNA modification in eukaryotic cells, which regulates vascular transcripts through splicing, degradation, translation, as well as translocation, thus maintaining microvascular homeostasis. Conversely, the disruption of the m6A regulatory network will lead to MVD. Herein, we provide a review discussing how m6A methylation interacts with MVD. We also focus on alterations of the m6A regulatory network under pathological conditions. Finally, we highlight the value of m6A regulators as prognostic biomarkers and novel therapeutic targets, which might be a promising addition to clinical medicine.

Sensitivity of Sniffer Dogs for a Diagnosis of Parkinson's Disease: A Diagnostic Accuracy Study.

BACKGROUND: The diagnostic criteria for Parkinson's disease (PD) remain complex, which is especially problematic for nonmovement disorder experts. A test is required to establish a diagnosis of PD with improved accuracy and reproducibility. OBJECTIVE: The study aimed to investigate the sensitivity and specificity of tests using sniffer dogs to diagnose PD. METHODS: A prospective, diagnostic case-control study was conducted in four tertiary medical centers in China to evaluate the accuracy of sniffer dogs to distinguish between 109 clinically established medicated patients with PD, 654 subjects without PD, 37 drug-naïve patients with PD, and 185 non-PD controls. The primary outcomes were sensitivity and specificity of sniffer dog's identification. RESULTS: In the study with patients who were medicated, when two or all three sniffer dogs yielded positive detection results in a sample tested, the index test sensitivity, specificity, and positive and negative likelihood ratios were 91% (95% CI: 84%-96%), 95% (95% CI: 93%-97%), and 19.16 (95% CI: 13.52-27.16) and 0.10 (95% CI: 0.05-0.17), respectively. The corresponding sensitivity, specificity, and positive and negative likelihood ratios in patients who were drug-naïve were 89% (95% CI: 75%-96%), 86% (95% CI: 81%-91%), and 6.6 (95% CI: 4.51-9.66) and 0.13 (95% CI: 0.05-0.32), respectively. CONCLUSIONS: Tests using sniffer dogs may be a useful, noninvasive, fast, and cost-effective method to identify patients with PD in community screening and health prevention checkups as well as in neurological practice. © 2022 International Parkinson and Movement Disorder Society.

A novel Nance-Horan syndrome mutation identified by next-generation sequencing in a Chinese family.

AIM: To identify the disease-causing mutation in a four-generation Chinese family diagnosed with Nance-Horan syndrome (NHS). METHODS: A Chinese family, including four affected patients and four healthy siblings, was recruited. All family members received ophthalmic examinations with medical histories provided. Targeted next-generation sequencing approach was conducted on the two affected males to screen for their disease-causing mutations. RESULTS: Two male family members diagnosed with NHS manifested bilateral congenital cataracts microcornea, strabismus and subtle facial and dental abnormalities, while female carriers presented posterior Y-sutural cataracts. A novel frameshift mutation (c.3916_3919del) in the NHS gene was identified. This deletion was predicted to alter the reading frame and generate a premature termination codon after a new reading frame. CONCLUSION: The study discovers a new frameshift mutation in a Chinese family with NHS. The findings broaden the spectrum of NHS mutations that can cause NHS in Chinese patients.

MEMS Inertial Sensor Calibration Technology: Current Status and Future Trends.

A review of various calibration techniques of MEMS inertial sensors is presented in this paper. MEMS inertial sensors are subject to various sources of error, so it is essential to correct these errors through calibration techniques to improve the accuracy and reliability of these sensors. In this paper, we first briefly describe the main characteristics of MEMS inertial sensors and then discuss some common error sources and the establishment of error models. A systematic review of calibration methods for inertial sensors, including gyroscopes and accelerometers, is conducted. We summarize the calibration schemes into two general categories: autonomous and nonautonomous calibration. A comprehensive overview of the latest progress made in MEMS inertial sensor calibration technology is presented, and the current state of the art and development prospects of MEMS inertial sensor calibration are analyzed with the aim of providing a reference for the future development of calibration technology.

Effects of long-chain noncoding RNA Linc00673 overexpression on proliferation and apoptosis of gastric cancer cell line MGC-803 / 中国应用生理学杂志

Objective: To investigate the effects of long-chain noncoding RNA Linc00673 overexpression on proliferation and apoptosis of gastric cancer cells and its mechanisms. Methods: The recombinant lentivirus expressing plasmid pLVX-Linc00673 and the control empty plasmid pLVX-NC were packaged and amplified in 293T cells, and the recombinant lentivirus was transfected into gastric cancer cell line MGC-803 to establish a cell line stably overexpressing Linc00673. The expression of Linc00673 gene was detected by real-time fluorescence quantitative PCR. The growth and proliferation of cells were observed by MTT assay and clone formation assay. Cell cycle and apoptosis were detected by flow cytometry. The expressions of cell cycle related regulatory genes were detected by qPCR. The expressions of key molecules in the PI3K/Akt signaling pathway and tumor proliferation related proteins were detected by Western blot. Results: The expressions of Linc00673 in gastric cancer cell line MGC-803, BGC-823 and AGS were significantly higher than that in normal gastric mucosa cell line GES-1 (P＜0.05). MGC-803 cell line with stable overexpression of LINC00673 was established, and the expression level of LincC00673 was 200 times higher than that of the control empty carrier group. Overexpression of Linc00673 promoted proliferation of MGC-803 cells (P＜0.05) and clone formation (P＜0.05), inhibited cell apoptosis and affected the G1→S phase progression of cell cycle (P＜0.01). Overexpression of Linc00673 could affect the expressions of cell cycle regulatory gene CCNG2, P19 and CDK1 in MGC-803. Western blot showed that Linc00673 overexpression not only promoted the expressions of the key molecule pAkt in PI3K / Akt signaling pathway and its downstream target NF-κ B and Bcl-2 protein, but also up regulated the expressions of tumor related factors β-catenin and EZH2 proteins. Conclusion: Overexpression of Linc00673 may promote proliferation and inhibit apoptosis of MGC-803 cells through PI3K/Akt signaling pathway.

CMV-IgG yeild in Guangzhou blood donors and comparison of different test reagents / 中国输血杂志

【Objective】 To investigate the CMV-IgG positive yeild among blood donors in Guangzhou and explore the differences in the efficacy of three test reagents, aimed at improving blood safety and service capacity of blood centers. 【Methods】 A total of 630 blood samples from eligible blood donors from July to October 2020 in our center were randomly selected and screened for CMV-IgG by one ELISA reagent.Among them, 180 samples were tested in parallel using three reagents (two ELISA reagents and one ECLIA reagent), and those tested negative were conducted quantitative CMV-DNA detection.The test results of different reagents were compared and analyzed. 【Results】 Out of the 630 samples, a total of 598 positive samples were screened out, including 180 samples yielded by three reagents, 171 and 175 by the two ELISA reagents, respectively, and 175 by ECLIA.The results given by three reagents were consistent (Kappa>0.4), and no significant difference in the positive yeild by three reagents was found.In the 180 samples, 11 were negative, among which 3, 2 and 6 samples were negative by all three reagents, two reagents and one reagent (ELISA), respectively.All the 11 samples were tested negative for CMV-DNA. 【Conclusion】 The yeild of positive CMV-IgG in blood donors was 94.9% (598/630), suggesting a high prevalence of CMV in Guangzhou. CMV serologically negative blood should be considered when providing blood products to immunocompromised patients to improve the safety of recipients.The detection results of ELISA reagents and ECLIA reagent for CMV- IgG are consistent, but ECLIA reagent has better detection efficacy.

HCV evolution and positive selection sites of HCV NS5B region among intravenous drug users in Guangdong / 中国输血杂志

【Objective】 To learn the situation of the evolution process of HCV virus population and the selection pressure of HCV NS5B in intravenous drug users (IDUs) in Guangdong. 【Methods】 141 blood samples from hepatitis C virus (HCV) RNA-positive blood donors and 58 from HCV patients in Guangdong were randomly collected for HCV NS5B sequence amplification, combined with HCV NS5B sequences from blood donors and IDUs obtained by sequencing previously(between 2009 and 2011). Homology analysis was performed by Molecular Evolutionary Genetics Analysis (MEGA) software, evolutionary analysis were performed by Bayesian Evolutionary Analysis Sampling Trees (BEAST) software package. Selection pressure analysis was performed on sequences isolated from IDUs by Datamonkey online software package with Mixed Effects Model Evolution (MEME) method, and the population expansion of species were analyzed using Tajima and Fu neutrality test by Arlequin software. 【Results】 The comparison results of internal homology among different subtypes of IDUs in this group were as follows : HCV-3b had the highest homology (97%), followed by HCV-3a (96%), HCV-6a (95%) and HCV-1b (94%); HCV evolution rate analysis showed that HCV-1b had the fastest evolution rate [2.17E-03 substitutions/site/year (y/y/y)], followed by HCV-3b (2.12E-0 y/y/y), HCV-3a (1.58E-03 y/y/y) and HCV-6a (1.28E-03 y/y/y). The analysis on effective population of HCV: 1980~1990 was rapid growth period for HCV-6a, 1990~1995 period for HCV-1b, and 2000~2007 period for HCV-3a. HCV population genetic characteristics was as follows: HCV-1b, 3a, 3b and 6a experienced population expansion, among which 3a and 3b were the most obvious. As to the analysis of HCV selection pressure, two positive selection sites (235 and 243)were found in the 339 nucleotide fragment of the NS5B sequence in injecting drug users, but mutation only occurred at position 316 [mutation rate 1.24% (14/1 130)] among 5 direct antiviral drug (DAA) sites in this gene. 【Conclusion】 The evolution of HCV-3b in Guangdong has showed an obvious trend of population expansion, with a high proportion and homology especially in the local IDUs. HCV-3b should be the focus of HCV prevention and control in this region. Given that the positively selected sites of the HCV NS5B gene region of IDUs in Guangdong are non-DAA binding sites, DAA is expected to demonstrate a good effect on these patients.

Preliminary identification of CD4 T cell epitopes in genotype 1 and 6 of hepatitis C virus / 中国输血杂志

【Objective】 To study the CD4 T cell epitopes in Core and NS3 protein of genotype 1(GT1) and 6(GT6) of hepatitis C virus(HCV). 【Methods】 A total of 298 overlapping peptides(16-mer) spanning Core and NS3 protein of GT1 and GT6 HCV were synthesized. Peripheral blood mononuclear cells(PBMCs) from 17 HCV+ and 7 healthy blood donors were stimulated by peptide pools, followed by evaluating T cell response by IFN-γ ELISPOT, by which 21 peptides with positive results were found. These peptides were further applied to individually stimulate 20 HCV+ and 18 healthy PBMCs. The differences of responsive frequencies to the 21 positive peptides between the two study groups were compared. 【Results】 Pooled and individual peptide stimulation tests showed that HCV+ PBMCs were responsive to the stimulation of 5 peptides(GT1 NS31273-1288 and NS31315-1330; GT6 NS31033-1048, NS31087-1102 and NS31351-1366), with a responsive frequency ranging 18.9%-27.0%. In contrast, healthy PBMCs were not or low responsive(0%-4.0%) to these five peptides. The responsive frequencies were statistically different between the two groups(P<0.05). No reported epitopes in IEDB were found identical with these 5 peptides via sequence alignment. 【Conclusion】 Our study identified novel CD4 T cell epitopes in NS3 protein of GT1 and GT6 HCV, which has potential application value for the research and development of HCV vaccine.

Assessment of Malaria Microscopy Competency at Primary Health Institutions in the Chongqing Municipality.

Background: In April 2019, Chongqing passed the national malaria elimination assessment. However, around 30 imported malaria cases are still being reported every year, and Anopheles sinensis was widely distributed in Chongqing, meaning the risk of malaria resurgence still exists. Early diagnosis and treatment for malaria cases are effective measures to prevent malaria resurgence. The primary health institutions are the first station where potential malaria cases may seek treatment. The competency with which primary health institutions diagnose malaria will directly affect the timeliness of malaria diagnosis. Nowadays, most primary health institutions in Chongqing use microscopy to confirm malaria cases. This study assessed the microscopy competence of primary health institutions, studied and analyzed the results, and provided a scientific basis for malaria prevention and control after malaria elimination in Chongqing. Methods: According to the stratified sampling principle, four plasmodium microscopy technicians (156 in total) were selected from each of the 39 districts/counties of Chongqing to test the plasmodium microscopy competence. Descriptive statistical analysis, correlation analysis, spatial self-correlation analysis, and ROC curve analysis were carried out on the test results. Result: The average of the technicians' test scores was 4.33 ± 0.47 (min: 3, mid: 4.5, max: 5); The spatial clustering of the scores was significant (MoranI = 0.338, Z = 3.618, P < 0.01). The test scores were positively correlated with the "level of work institutions" (R = 0.21, P < 0.01) but were negatively correlated with "age" (R = -0.31, P < 0.01). The highest Sensitivity of the technicians' microscopy was in qualitative diagnosis (98.92%, CI: 98.00-99.69%). The Delong's test showed that the diagnostic efficiency of the technicians' microscopy to P. falciparum was the best (P < 0.01), however to P. ovale was the worst (P < 0.01). Conclusion: The microscopy technicians in primary health institutions in Chongqing have good microscopy competency in qualitative diagnosis, but there were deficiencies in the identification of plasmodium species. Township level health institutions in Central China have weaker microscopy than those in other areas.

Correlation of peripheral myeloid-derived suppressor cells with hepatitis c virus infection / 中国输血杂志

【Objective】 To investigate the correlation of peripheral myeloid-derived suppressor cells (MDSC) with hepatitis c virus (HCV) infection. 【Methods】 109 voluntary blood donors who donated blood during February 2018 to September 2020 at Guangzhou Blood Center were recruited in this study. They were assigned to chronic hepatitis c (CHC) group (n=48), spontaneous clearance (SC) group (n=29) and healthy donors (control) group (n=32) according to the results of anti-HCV and HCV RNA tests. Blood samples were drawn from the participants and peripheral blood mononuclear cells (PBMC) were freshly isolated, followed by staining with fluorescently-labeled antibody against cell surface markers of MDSC, which were then applied to the detection of monocytic- (M) and polymorphonuclear (PMN)-MDSC by flow cytometry. Parameters for liver function including alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), total bilirubin (TBIL) and direct bilirubin (DBIL) were also measured. One-way ANOVA tests were applied to compare the differences of M- and PMN-MDSC and liver function between three study groups. For pairwise comparisons, P values were adjusted for multiple comparisons by Bonferroni correction (Pc). 【Results】 The frequencies of M-MDSC (%) in CHC, SC and HC were 1.39±0.86, 0.85±0.63 and 0.57±0.23, respectively (P0.05). In addition, AST (34.4±19.2 vs 23.0±7.78 U/L) and GGT (40.8±31.4 vs 22.3±7.40 U/L) level were higher in CHC compared with control (Pc<0.05 and Pc<0.01, respectively). 【Conclusion】 The level of peripheral M-MDSC was significantly elevated in chronic HCV infected donors, which would related to the progression of chronicity after HCV infection.