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【Objective】 To study the effects of different storage temperature and different storage time on the activity of key growth factors in platelet-rich plasma(PRP), and to provide a theoretical basis for maximize the role of PRP in clinical treatment. 【Methods】 PRP was collected by blood cell isolation and apheresis, stored at 22℃ and -80℃, respectively. VEGF, TGF-β and PDGF were detected by ELISA. The content of growth factors in PRP was detected when stored at 22℃for 1, 3 and 5 days, and the growth factors content of PRP stored at 22℃ for 3 days was detected after thrombin activation for 0.5, 1 and 1.5 hours. The content of growth factor in frozen PRP (stored at -80℃ for 30 days after initial 3-days storage at 22℃ ) and fresh PRP (stored at 22℃ for 3 days) was compared. The growth factor content in PRP frozen at - 80℃ for 30, 60 and 180 days, and the growth factor content in PRP frozen at -80℃ for 180 days after repeated freeze-thaw for 1, 2, 3, 5 and 10 times were detected. 【Results】 The growth factor content of apheresis PRP was significantly higher than that of platelet-poor plasma. No statistical difference was noticed in VEGF, TGF-β and PDGF content in PRP at 1, 3 and 5 days stored at 22℃; no statistical difference was noticed in VEGF, TGF-β and PDGF content in PRP stored at 22℃ for 3 days after thrombin activation for 0.5, 1 and 1.5 hours. There was no statistically significant difference in growth factor content between PRP stored at 22℃ for 3 days versus frozen at -80℃ for 30 days after initial 3-days storage at 22℃. No statistical difference was found in VEGF, TGF-β and PDGF contents in frozen PRP repeatedly frozen and thawed for 1 to 10 times. 【Conclusion】 Apheresis PRP can release a large amount of growth factors after activation. Fresh PRP stored at 22℃ for 5 days or frozen at -80℃ for 180 days has no impact on the content of growth factors, and frozen PRP at -80℃ can achieve long-term, effective and safe preservation, which is conducive to multiple use of PRP in treatment.
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Objective:To analyze the whole genome of Omicron variants causing the first local Omicron outbreak in Henan Province and to investigate the mutations in the SARS-CoV-2 genome for source tracing.Methods:Respiratory tract samples from COVID-19 cases in the Omicron outbreak in Henan Province from January 7 to 29, 2022 were subjected to whole-genome sequencing and sequence alignment analysis. Whole-genome identity, variations and evolution of the Omicron variants were analyzed.Results:Through high-throughput sequencing, the whole-genome sequences of SARS-CoV-2 were obtained from 120 cases, which accounted for 25.64% (120/468) of all COVID-19 cases in Anyang during the same period. Compared with the genome of Wuhan reference strain (NC_045512.2), there were 57-59 nucleotide mutation sites in the 120 whole genome sequences, and one or two nucleotide mutation sites were added to the shared 57 nucleotide sites. All of the 120 strains were VOC/Omicron (BA.1.1) variants and shared high homology. The whole-genome sequence obtained from the first case A contained 57 nucleotide mutation sites, while apart from the 57 identical nucleotide mutation sites, one specific mutation site (C1594T) was found in the whole-genome sequence obtained from the first case B, suggesting that the two cases were in the same transmission chain. After comparing with the database of domestic and imported cases by the Chinese Center for Disease Control and Prevention and the Henan Provincial Center for Disease Control and Prevention, it was found that the current outbreak was linked with the same transmission chain as the existing local epidemics in other provinces. Moreover, epidemiological investigation showed that on January 2, case A had come into contact with her cousin and his family who returned from an affected area outside the province.Conclusions:Based on the gene sequencing results and epidemiological investigation, the COVID-19 outbreak in Anyang city, Henan Province was a local epidemic and the source of it was a college student who returned to Anyang city from other province on December 28, 2021. These infections were linked to the same transmission chain as the existing local infection in other provinces.
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Objective:To analyze the genome characteristics and variations in nucleotides and amino acids of SARS-CoV-2 causing an outbreak in Henan Province in November 2021 and perform the traceability analysis.Methods:In this study, throat swab specimens from cases in the acute phase were collected and tested for the nucleic acids of SARS-CoV-2 by real-time fluorescent RT-PCR. SARS-CoV-2 nucleic acid-positive samples were subjected to high-throughput genome sequencing and whole-genome alignment analysis.Results:The median Ct values of ORF1ab gene and N gene in 70 positive specimens was 26.41 (15.58 to 39.27) and 24.43 (12.04 to 39.74), respectively. Compared with the sequence of Wuhan-Hu(NC_045512) reference strain, 47 to 49 nucleotide mutations sharing 47 nucleotide mutation and 41 amino acid mutations were found in 63 strains of successfully sequenced SARS-CoV-2. Nine nucleotide mutations and 12 amino acid mutations were found in the spike protein. The index case shared 47 mutations with the Russian imported cases in Henan Province on October 14 and the local cases in Jiangxi Province in October. Moreover, their genomes were highly homologous and they all belonged to the Delta variant (AY.122 evolutionary branch).Conclusions:Continuous monitoring of imported COVID-19 cases and prolonging the period of quarantine were needed to reduce the risk of local outbreak and epidemic caused by imported COVID-19 cases. Analysis of the genomic characteristics of SARS-CoV-2 and the variations in nucleotides and amino acids was conducive to trace the origin of COVID-19 outbreak quickly and provide reference for precise control.
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Objective:To explore the mediating effect of self-compassion between family cohesion and loneliness among adolescents.Method:From November to December 2020, a total of 626 adolescents were investigated with the family adaptability and cohesion scale, children loneliness scale and the self-compassion scale short form.Data were analyzed by SPSS 23.0 and PROCESS v 2.16 softwares.The statistical methods included t-test, one-way ANOVA, Pearson correlation analysis and intermediary effect analysis. Results:Compared with girls, boys’ score of family cohesion((63.52±8.47), (65.48±9.07)) was significantly lower but the scores of self-compassion((37.68±5.26), (36.49±5.75)) and loneliness((37.74±10.44), (36.01±10.48)) were significantly higher( t=-2.79, 2.06, 2.70; all P<0.05). There was no significant difference in the scores of family cohesion((63.67±8.71), (64.74±8.85)), self-compassion((37.45±5.71), (36.98±5.49)) and loneliness((36.60±10.52), (36.96±10.49)) between left-behind and non-left-behind children( t=1.29, -0.87, 0.38, all P>0.05). The score of family cohesion of the adolescents from Grade 7 was significantly lower than those of Grade 8, Grade 10 and Grade 11( P<0.01), while the score of self-compassion of the adolescents from Grade 10 was significantly lower than those of Grade 7 and Grade 11(both P<0.01), but the score loneliness of the adolescents from Grade 11 was significantly lower than those of Grade 8 and Grade 10(both P<0.05). Family cohesion(64.50±8.82)was significantly positively associated with self-compassion(37.09±5.54)( r=0.22; P<0.01). Loneliness(36.88±10.49)were significantly negatively associated with self-compassion( r=-0.27, P<0.01) and family cohesion( r=-0.28, P<0.01). The relation between family cohesion and loneliness was partly mediated by self-compassion and the effect of mediation was 20.9%. Conclusion:Family cohesion will not only directly affect the loneliness of adolescents, but also affect loneliness through the mediating effect of self-care.
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Objective:To explore the effect sense of security and self-control on parent-child cohesion and externalizing problem behaviors in primary and middle school students.Methods:A total of 1 402 primary and middle school students were investigated with the problem behavior frequency scale(PBFS), family adaptability and cohesion scale(FACES-CV), security questionnaire(SQ) and brief self-control scale(BSCS). SPSS 25.0 and PROCESS v2.16 were used for statistical analysis, and common method deviation test, Pearson correlation analysis and intermediary effect analysis were used in the analysis.Results:Parent-child cohesion of primary and middle school students was positively correlated with security and self-control ( r=0.279, 0.303, both P<0.01), which was negatively correlated with externalizing problem behaviors ( r=-0.154, P<0.01). Security was positively correlated with self-control ( r=0.567, P<0.01). Security, self-control and externalizing problem behaviors were negatively correlated ( r=-0.147, -0.250, both P<0.01). The security and self-control of primary and middle school students played a partial mediating role between parent-child cohesion and externalizing problem behaviors.The mediating effect consisted of two paths: one was parent-child cohesion-self-control-externalizing problem behaviors, the other was parent-child cohesion-security-self-control-externalizing problem behaviors. The effect values of these two paths accounted for 20.52% and 20.26% of the total effect respectively. Conclusion:Parent-child cohesion not only directly affects the externalizing problem behaviors of primary and middle school students, but also indirectly affects the externalizing problem behavior through the independent mediating effect of self-control and the chain mediation of security-self-control.
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Objective:To provide data support for the prevention and control of dengue fever in Henan Province by analyzing the molecular epidemiological and etiological characteristics of dengue fever outbreaks in Puyang in 2019.Methods:Blood samples were collected from all suspected cases of dengue fever. The antigen, antibody and nucleic acid of dengue virus (DENV) were detected. The E gene was amplified by viral nucleic acid extraction and sequenced. Phylogenetic tree was constructed to trace the source of infection. Results:A total of 61 local cases of dengue fever were reported, and no deaths were reported. Among them, 4 cases (72.13%) were positive for DENV NS1 antigen; 16(26.23%) cases were positive for specific IgM; 38(62.30%) cases were positive for specific IgG; 34 cases (54.10%) were positive for dengue nucleic acid testing. Ten dengue virus strains were isolated, all of which were dengue virus type 1(DENV-1). Sequence analysis of E gene suggested it belonged to the same clade as Henan201903 strain imported from Cambodia to Zhumadian, Henan in 2019, with the highest homology. Conclusions:The dengue fever epidemic in Henan Province was caused by DENV-1, which might be improted from Cambodia, Singapore, Myanmar and other Southeast Asian countries. Therefore, the surveillance of DENV in people returning from Southeast Asia should be strengthened.
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Objective:To monitor the changes in specific IgM and IgG antibodies in patients diagnosed with COVID-19 after SARS-CoV-2 infection, and analyze their clinical significance.Methods:A total of 168 serum samples were collected from 56 COVID-19 patients with different disease courses who were positive for nucleic acid test at Henan Center for Disease Control and Prevention on January 8, 2020 and February 21, 2020. Serum samples from 25 healthy people excluded from COVID-19 were used as control group. IgM and IgG antibodies against SARS-CoV-2 were detected by chemiluminescence method.Results:IgM antibody increased sharply in 1-3 weeks after onset, and reached the peak value (21.78 AU/ml) in the 3rd week after onset. IgG antibody increased the most in 3-6 weeks after onset, and reached the peak value (81.58 AU/ml) in the 9th week after onset. The levels of IgM and IgG antibodies were closely correlated with age and disease course ( P<0.05). The antibody level of 30-60 years old group was the highest, the IgM antibody positive rate and antibody level of acute stage and previous infection were lower than that of recovery stage, and the IgG antibody positive rate and antibody level of acute stage were lower than that of recovery stage and previous infection. During the whole course of the disease, the levels of IgM and IgG antibodies increased gradually in the acute stage, reached the peak in the recovery stage, and decreased and maintained at a certain level in the past infection. Conclusions:Serum SARS-CoV-2 IgM and IgG antibody detection can be used as auxiliary diagnostic indicators for COVID-19, and its continuous observation is helpful for epidemiological investigation, serological diagnosis and disease course monitoring.
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Objective:To analyze the evolutionary characteristics and variations of 2019 novel coronavirus (2019-nCoV) strains imported from abroad in Henan Province.Methods:A total of 16 imported cases of coronavirus disease 2019 (COVID-19) reported in Henan Province from May to December 2020 were enrolled. The throat swab specimens from the patients were collected and sent to the Henan Provincial Center for Disease Control and Prevention for whole genome sequencing. Taking SARS-CoV-2 Wuhan-Hu-1 published in Global Initiative on Sharing All Influenza Data (GISAID) as the reference sequence, the sequences were aligned and analyzed by MEGA X, and the phylogenetic tree was constructed by the maximum likelihood method.Results:Among 16 cases, 13 cases were imported from Russia, two cases were imported from Myanmar, and one case was imported from Ukraine. A total of 16 strains of 2019-nCoV genomes with the lengths of 29 804 bp to 29 882 bp were obtained. A total of 145 nucleotide mutations and 80 amino acid mutations were detected. Nucleotide variations of C241T, C3037T, C14408T, A23403G and the amino acid variation of D614G in spike protein were detected in all sequences. Meanwhile, insertion A at the site of 29704 was found in BetaCov/HEN02/Human/2020, BetaCov/HEN04/Human/2020 and BetaCov/HEN05/Human/2020. Deletion variation was not found. Phylogenetic analysis showed that there was no correlation between the 16 strains and currently epidemic variants of concern (VOC) .Conclusion:From May to December 2020, the detection of viral genome mutations in the imported cases of Henan Province shows randomness and diversity, while the strains are not VOC.
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Objective:To explore the mediation effect of personality between negative life events and risky mentation of university students.Methods:A cross sectional investigation was conducted among 8 379 freshmen with the adolescent self-rating life events check list (ASLEC), the prodromal questionnaire(PQ-16) and the Eysenck personality questionnaire (EPQ). The data were analyzed by SPSS 23.0 and AMOS 24.0.Results:The total score of negative life events scale((31.16±0.58) vs (15.19±0.15)), the scores of neuroticism((58.20±0.36) vs (41.59±0.13)) and psychoticism((53.07±0.29) vs (47.71±0.08)) in the risk psychological state group were significantly higher ( t=26.611, 42.270, 17.286, all P<0.01), and the score of introversion-extroversion factor was significantly lower((49.83±0.42) vs (55.88±0.13), t=-13.634, P<0.01) than those in the risk-free psychological state group. There was a positive correlation between the scores of risk psychological state and negative life events( r=0.290, 0.334, both P<0.01), and the scores of risk psychological state and negative life events were positively correlated with the scores of personality neuroticism and psychoticism ( r=0.139-0.469, all P<0.01) in both risk psychological state and risk-free psychological state group.The risk psychological state score of college students was negatively correlated with the inside and outside personality score( r=-0.070, P<0.01), and the score of negative life events was not correlated with introversion-extroversion personality score in the risk psychological state group, while the score of risk psychological state, negative life events and introversion-extroversion personality score were negatively correlated in the risk-free psychological state group ( r=-0.177, -0.080, P<0.01). The personality of college students played a complete mediating role between negative life events and risk psychological state in the risk psychological state group, while the personality of college students in the risk-free psychological state group played a partial mediating role between negative life events and risk psychological state, accounted for 71.43% of the total effect. Conclusion:Negative life events not only directly lead to the risky mentation of college students, but also affect the risky mentation of college students by the mediation effect of introverted and extroverted tendency and unstable emotion.
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Objective:To investigate whether idebenone can improve behavioral disorders in mice with Parkinson disease (PD) by increasing PHB2 mediated mitophagy.Methods:In the first small experiment, thirty mice were randomly divided into normal control group, model group and treatment group according to the random number table method, with 10 animals in each group.The aim of this study was to observe the effect of idebenone on the behavior of Parkinson disease model mice. In the second experiment, 20 mice were randomly divided into blank control group, MPTP group, shRNA-PHB2 group and shRNA-PHB2+ MPTP group, with 5 mice in each group. The changes of tyrosine dehydrogenase (TH) in brain tissue were detected by immunofluorescence assay. In the third experiment, 30 mice were randomly divided into blank control group, shRNA-PHB2 group, MPTP+ idebenone group, shRNA-PHB2+ MPTP group, shRNA-PHB2+ idebenone group and shRNA-PHB2+ MPTP+ idebenone group, with 5 animals in each group. The aim of this study was to investigate the effect of idebenone on mitochondrial autophagy in mouse brain.C57BL-6 mice were intraperitoneally injected with MPTP to establish the animal model of chronic PD. Then 200 mg / kg idebenone was given by gavage for 21 days. And the expression of PHB2 in brain was inhibited by microinjection of adeno-associated virus 9 (AAV9) shRNA inhibin 2(PHB2) into lateral ventricle. The behavioral changes of the PD mice were detected by Morris water maze, and the changes of tyrosine dehydrogenase (TH) induced by inhibiting PHB2 were detected by immunohistochemistry. The protein expression of LC3 and PHB2 in substantia nigra of midbrain was detected by Western blot.The data were analyzed by GraphPad 7.0 and SPSS 22.0.Results:(1) In the water maze test data of the first small experiment, the repeated measurement ANOVA showed that the group-time interaction effects of latency of mice from 1 to 7 days were significant ( Ftime×group=20.51, P<0.05). Simple effect analysis showed that on the 5th, 6th and 7th day, the incubation period of the treatment group was significantly shortened (all P<0.05). Univariate analysis of variance showed that on the 7th day of the test, the differences between the control group and the model group, the model group and the treatment group, the control group and the treatment group were all statistically significant( t=-49.95, -21.81, 28.14; all P<0.01). In the third small experiment, repeated measurement analysis of variance showed that the interaction between time and group was significant ( Ftime×group=42.11, P<0.01). Simple effect analysis showed that compared with MPTP+ idebenone group, the latency of shRNA-PHB2+ MPTP+ idebenone group was significantly prolonged (all P<0.05). There were no significant difference between shRNA-PHB2+ MPTP+ idebenone group and shRNA-PHB2+ MPTP group except the 4th day ( P<0.05). On the 7th day, compared with MPTP+ idebenone group, the residence time of shRNA-PHB2+ MPTP+ idebenone group was significantly increased ( t=-34.36, P<0.001), but there was no significant difference between shRNA-PHB2+ MPTP group and shRNA-PHB2+ MPTP+ idebenone group ( t=2.94, P>0.05). (2)The results of immunofluorescence experiment showed that the relative expression of TH in the control group, model group, shRNA-PHB2 group and shRNA-PHB2+ MPTP group were (41.03±3.01), (24.20±4.18), (38.39±3.31) and (13.12±2.65), respectively. Compared with the control group, the expression of TH in the midbrain of the MPTP group was significantly down-regulated, the difference was statistically significant( t=7.98, P<0.01). Compared with the MPTP group, the expression of TH in shRNA-PHB2 group was down regulated ( t=-6.73, P<0.05). (3) Western blot results showed that the relative expression of LC3 in midbrain tissue of control group, shRNA-PHB2 group, MPTP+ idebenone group, shRNA-PHB2+ MPTP group, shRNA-PHB2+ idebenone group and shRNA-PHB2+ MPTP+ idebenone group were (0.86±0.07), (0.77±0.08), (0.42±0.05), (0.21±0.05), (0.66±0.09) and (0.27±0.07). The relative expression of PHB2 were (1.13±0.14), (0.56±0.11), (1.08±0.14), (0.27±0.07), (0.68±0.14) and (0.24±0.10). Compared with MPTP+ idebenone group, the relative expression of LC3 and PHB2 in shRNA-PHB2+ MPTP+ idebenone group was significantly decreased ( F=1.96, P<0.01). Conclusion:Idebenone can increase the level of mitophagy in PD mice through PHB2, thus improving the behavioral disorder.
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Myelodysplastic syndrome (MDS) is characterized by dysplastic and ineffective hematopoiesis that can result from aberrant expansion and activation of myeloid-derived suppressor cells (MDSC) within the bone marrow microenvironment. The proliferation and activation of MDSC lead to the dysfunction and depletion of natural killer cells and CD8 + T cells, and the recruitment of inflammatory cells and factors leads to the further accumulation of genetic abnormalities in MDS patients, leading to the progression of MDS. The accumulation of inflammatory cytokines in the tumor environment induces the expression of programmed death receptor 1 (PD-1) in hematopoietic stem cells and hematopoietic progenitor cells and the overexpression of programmed death receptor ligand 1 (PD-L1) in MDSC, and the interaction of PD-1/PD-L1 leads to the apoptosis of MDS hematopoietic progenitor cells and ineffective hematopoiesis. The experiments and clinical studies targeting MDSC have confirmed that correcting or reversing the bone marrow microenvironment of immune disorders in MDS is a therapeutic strategy to restore effective hematopoietic function.
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Although genome-wide association studies have identified more than eighty genetic variants associated with non-small cell lung cancer (NSCLC) risk, biological mechanisms of these variants remain largely unknown. By integrating a large-scale genotype data of 15 581 lung adenocarcinoma (AD) cases, 8350 squamous cell carcinoma (SqCC) cases, and 27 355 controls, as well as multiple transcriptome and epigenomic databases, we conducted histology-specific meta-analyses and functional annotations of both reported and novel susceptibility variants. We identified 3064 credible risk variants for NSCLC, which were overrepresented in enhancer-like and promoter-like histone modification peaks as well as DNase I hypersensitive sites. Transcription factor enrichment analysis revealed that USF1 was AD-specific while CREB1 was SqCC-specific. Functional annotation and gene-based analysis implicated 894 target genes, including 274 specifics for AD and 123 for SqCC, which were overrepresented in somatic driver genes (ER = 1.95, P = 0.005). Pathway enrichment analysis and Gene-Set Enrichment Analysis revealed that AD genes were primarily involved in immune-related pathways, while SqCC genes were homologous recombination deficiency related. Our results illustrate the molecular basis of both well-studied and new susceptibility loci of NSCLC, providing not only novel insights into the genetic heterogeneity between AD and SqCC but also a set of plausible gene targets for post-GWAS functional experiments.
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Humans , Adenocarcinoma of Lung/genetics , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Squamous Cell/genetics , Genetic Heterogeneity , Genetic Predisposition to Disease , Genome-Wide Association Study , Lung Neoplasms/genetics , Polymorphism, Single NucleotideABSTRACT
Background: Sex-disaggregated data suggest that men with coronavirus disease 2019 (COVID-19) are more likely to die than women. Whether circulating testosterone or sex hormone-binding globulin (SHBG) contributes to such sex differences remains unknown. Objective: To evaluate the associations of circulating total testosterone (TT), free testosterone (FT), and SHBG with COVID-19 mortality. Design: Prospective analysis. Setting: UK Biobank. Participants: We included 1306 COVID-19 patients (678 men and 628 women) who had serum TT and SHBG measurements and were free of cardiovascular disease or cancer at baseline (2006-2010). Main outcome measures: The death cases of COVID-19 were identified from National Health Service death records updated at 31 July 2020. Unconditional logistic regression was performed to estimate the odds ratio (OR) and 95% confidence intervals (CI) for mortality. Results: We documented 315 deaths of COVID-19 (194 men and 121 women). After adjusting for potential confounders, we did not find any statistically significant associations for TT (OR per 1-SD increase = 1.03, 95% CI: 0.85-1.25), FT (OR per 1-SD increase = 0.95, 95% CI: 0.77-1.17), or SHBG (OR per 1-SD increase = 1.09, 95% CI: 0.87-1.37) with COVID-19 mortality in men. Similar null results were observed in women (TT: OR per 1-SD increase = 1.10, 95% CI: 0.85-1.42; FT: OR per 1-SD increase = 1.10, 95% CI: 0.82-1.46; SHBG: OR per 1-SD increase = 1.16, 95% CI: 0.89-1.53). Conclusions: Our findings do not support a significant role of circulating testosterone or SHBG in COVID-19 prognosis.
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BackgroundCoronavirus disease 2019 (COVID-19) deteriorates suddenly primarily due to excessive inflammatory injury, and insulin-like growth factor-1 (IGF-1) is implicated in endocrine control of the immune system. However, the effect of IGF-1 levels on COVID-19 prognosis remains unknown. ObjectiveTo investigate the association between circulating IGF-1 concentrations and mortality risk among COVID-19 patients. DesignProspective analysis. SettingUK Biobank. Participants1425 COVID-19 patients who had pre-diagnostic serum IGF-1 measurements at baseline (2006-2010). Main outcome measuresCOVID-19 mortality (available death data updated to 22 May 2020). Unconditional logistic regression was performed to estimate the odds ratio (OR) and 95% confidence intervals (CIs) of mortality across the IGF-1 quartiles. ResultsAmong 1425 COVID-19 patients, 365 deaths occurred due to COVID-19. Compared to the lowest quartile of IGF-1 concentrations, the highest quartile was associated with a 37% lower risk of mortality (OR: 0.63, 95% CI: 0.43-0.93, P-trend=0.03). The association was stronger in women and nonsmokers (both P-interaction=0.01). ConclusionsHigher IGF-1 concentrations are associated with a lower risk of COVID-19 mortality. Further studies are required to determine whether and how targeting IGF-1 pathway might improve COVID-19 prognosis.
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BackgroundPrevious studies have showed clinical characteristics of patients with the 2019 novel coronavirus disease (COVID-19) and the evidence of person-to-person transmission. Limited data are available for asymptomatic infections. This study aims to present the clinical characteristics of 24 cases with asymptomatic infection screened from close contacts and to show the transmission potential of asymptomatic COVID-19 virus carriers. MethodsEpidemiological investigations were conducted among all close contacts of COVID-19 patients (or suspected patients) in Nanjing, Jiangsu Province, China, from Jan 28 to Feb 9, 2020, both in clinic and in community. Asymptomatic carriers were laboratory-confirmed positive for the COVID-19 virus by testing the nucleic acid of the pharyngeal swab samples. Their clinical records, laboratory assessments, and chest CT scans were reviewed. FindingsNone of the 24 asymptomatic cases presented any obvious symptoms before nucleic acid screening. Five cases (20.8%) developed symptoms (fever, cough, fatigue, etc.) during hospitalization. Twelve (50.0%) cases showed typical CT images of ground-glass chest and 5 (20.8%) presented stripe shadowing in the lungs. The remaining 7 (29.2%) cases showed normal CT image and had no symptoms during hospitalization. These 7 cases were younger (median age: 14.0 years; P = 0.012) than the rest. None of the 24 cases developed severe COVID-19 pneumonia or died. The median communicable period, defined as the interval from the first day of positive nucleic acid tests to the first day of continuous negative tests, was 9.5 days (up to 21 days among the 24 asymptomatic cases). Through epidemiological investigation, we observed a typical asymptomatic transmission to the cohabiting family members, which even caused severe COVID-19 pneumonia. InterpretationThe asymptomatic carriers identified from close contacts were prone to be mildly ill during hospitalization. However, the communicable period could be up to three weeks and the communicated patients could develop severe illness. These results highlighted the importance of close contact tracing and longitudinally surveillance via virus nucleic acid tests. Further isolation recommendation and continuous nucleic acid tests may also be recommended to the patients discharged.
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Objective:To analyze the neutralization properties of different genotypes and mutants of severe fever with thrombocytopenia syndrome virus (SFTSV).Methods:Pseudoviruses of SFTSV of different genotypes and mutants were constructed using VSVΔG-Fluc*G backbone. Neutralization assays were established based on the pseudoviruses. DNA vaccines for different SFTSV genotypes were prepared. Serum samples were collected from guinea pigs immunized with the DNA vaccines. Neutralizing antibodies in serum samples from immunized guinea pigs and naturally infected patients were detected using neutralization assays and analyzed.Results:The pseudoviruses of five genotypes and 43 mutants were successfully constructed and the neutralization assays based the pseudoviruses were successfully established after optimizing the reaction parameters. The dilution multiple corresponding to the inhibition rate of neutralizing antibody to half of the pseudovirus infection was taken as the titer of neutralizing antibody by the reduction in pseudovirus reporter gene. The neutralization antibody titers in naturally infected patients and immunized guinea pigs were respectively in the ranges of 1∶100-1∶43 000 and 1∶100-1∶2 500 when detected with the reference HB29 pseudovirus. The neutralization antibody titers ranged from 1∶100-1∶2 500 after immunization with different genotypes of DNA vaccines. No significant statistical difference in neutralization antibody titer was observed among different genotypes or mutant strains.Conclusions:The neutralization properties of different genotypes and mutants showed no significant change, which would be very useful for developing vaccines.
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Objective:To investigate the performance of real-time RT-PCR for the detection of SARS-CoV-2 nucleic acid in clinical diagnosis of COVID-19.Methods:Laboratory test data and basic case information of Henan COVID-19 cases were collected from the China′s Infectious Disease Information System as of March 5, 2020. All information was entered by local hospitals and Center for Disease Control and Prevention (CDC). Local hospitals or country CDC were responsible for sampling and municipal CDC was responsible for nucleic acid testing.Results:A total of 6 714 specimens were detected and the positive rate of SARS-CoV-2 nucleic acid was 23.82%. The specimens were collected from 1 200 confirmed cases, 2 178 suspected cases and 77 asymptomatic cases. The nucleic acid diagnosis rate of COVID-19 was 36.96% (1 277/3 455). In all cases, the positive rates of SARS-CoV-2 nucleic acid in nasal swabs, sputum samples and throat swabs were 19.38%, 28.59% and 23.53%, respectively (χ 2=15.896, P<0.01). The positive rate of SARS-CoV-2 nucleic acid in confirmed COVID-19 cases was 63.10%. The positive rates in nasal swabs, sputum samples and throat swabs were 50.80%, 58.71% and 65.21 (χ 2=18.612, P<0.01). The positive rates of SARS-CoV-2 nucleic acid were 43.51%, 23.98%, 22.82%, 12.17%, 14.46% and 13.21% in samples collected on the day of symptom onset and one week, two weeks, three weeks, four weeks, five weeks and above five weeks after the onset, respectively. The positive rates in confirmed cases were respectively 89.03%, 86.57%, 52.30%, 17.53%, 17.69% and 24.14% at those time points. Conclusions:Real-time RT-PCR is the most effective method for early pathogenic diagnosis of COVID-19. The highest detection rate of nucleic acid is achieved within one week after the onset of COVID-19, and the latest time for nucleic acid detection is 38 d after the onset.
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Objective:To evaluate the application of fractional exhaled nitric oxide (FeNO) and peripheral blood eosinophil (EOS) count in the diagnosis of eosinophilic asthma.Methods:The clinical data of 89 patients newly diagnosed as asthma in Department of Respiratory and Critical Medicine of the First Hospital of Shanxi Medical University from May 2016 to March 2018 were retrospectively analyzed. Pulmonary function, FeNO, induced sputum cytology classification and peripheral blood cell analysis were performed. The EOS% in induced sputum ≥3% was used as criteria for diagnosis of eosinophilic asthma (eosinophilic asthma group, n=34), and the other 55 patients were included in non-eosinophilic asthma group. The pulmonary function of the two groups were compared. The correlations among FeNO, EOS% in induced sputum and peripheral blood EOS count were analyzed. The diagnostic efficiency and optimal thresholds points of FeNO and peripheral blood EOS count to diagnose eosinophilic asthma were assessed by ROC curves. Results:The forced expiratory volume in one second (FEV 1)/pre(%) was (90.3±26.1)% and FEV 1/ forced vital capacity (FVC) was (69.1±11.8)% of the eosinophilic asthma group, which were significantly lower than those of the non-eosinophilic asthma group [(110.1±20.3)%, t=4.014, P<0.01 and (80.1±6.0)%, t=5.003, P<0.01]. FeNO was positively correlated with the EOS% in induced sputum ( r=0.670, P<0.01), peripheral blood EOS count was positively correlated with EOS% in induced sputum ( r=0.741, P<0.01), peripheral blood EOS count was positively correlated with FeNO ( r=0.647, P<0.01). The optimal cut-off of FeNO value was 65 ppb (AUC=0.887, P<0.01) and the sensitivity was 0.647, the specificity was 1.000. The optimal cut-off of peripheral blood EOS count was 0.225×10 9/L (AUC=0.898, P<0.01), the sensitivity and specificity were 0.794 and 0.891, respectively. The combination of FeNO and peripheral blood EOS count had better diagnostic value (AUC=0.916, P<0.01) with a sensitivity of 0.794 and a specificity of 0.945. Conclusion:FeNO and peripheral blood EOS count are reliable indicators for the diagnosis of eosinophilic asthma, and the combination of the two indicators can more effectively predict the presence of eosinophilic airway inflammation in patients with asthma.
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Chronic lymphocytic leukemia (CLL) is a highly heterogeneous disease, and combined chemotherapies symbolized by rituximab + fludarabine + cyclophosphamide have made great achievements in the era of traditional immunochemotherapy. However, for the patients with high genetic risk, relapsed and refractory patients as well as the elderly patients who cannot tolerate it, the therapeutic effect of this regimen is not good. The new drugs represented by BTK inhibitors have solved the above problems to a certain extent, and it is hopeful to move into the chemotherapy-free age of CLL treatment and bring the possibility of drug withdrawal. This article reviews the progress of CLL treatment.
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Objective:To explore the effect of negative affect on internet addiction among college students, and the mediating effect of fatigue.Methods:Totally 8 371 freshmen from North China University of Science and Technology were assessed with Chen Shuhui Chinese Network Scale, Fatigue Assessment Scale and Positive Negative Emotion Scale.SPSS 23.0 was used to analyze the data and test the intermediary effect.Results:Both of the total score of internet addiction scale and the scores of each factor were negatively correlated with positive emotions scores ( r=-0.337- -0.269, P<0.01). However, theose were positively correlated with the negative emotion scores( r=0.338-0.417, P<0.01), the fatigue severity scores( r=0.029-0.040, P<0.01), and the environment specific score and the result score of fatigue( r=0.021-0.028, P<0.05). The emotion and fatigue of college students could predict internet addiction, which could explain 36.9% variation of total score of internet addiction( F=979.336, P<0.01). Fatigue played a part in mediating between internet addiction and negative emotions. Conclusion:Negative emotions not only directly affect the degree of internet addiction of college students, but also indirectly affect the degree of internet addiction of college students through part of the intermediary role of fatigue.
