Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.

Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.

Objective:To understand the prevalence and characteristics of Rhinovirus (HRV) infection in influenza-like Illness (ILIs) patients in Mianyang, Sichuan province, China.Methods:Throat swabs were collected from patients of ILIs in sentinel hospitals in Mianyang during 2021—2022. Real-time fluorescence quantitative PCR was used to detect 16 common pathogens. The VP4/VP2 coding region genes of HRV positive samples were amplified by nest PCR. The phylogeny, consistency and amino acid variation of different serotypes were analyzed and compared with reference sequences from GenBank database.Results:A total of 332 ILIs′ samples were collected with a virus detection rate of 58.73% (195/332) in Mianyang. Among them, 23 samples (23/332) were HRV-positive, and 18 VP4/VP2 sequences of HRV strains were successfully amplified. It was found that 13 HRV serotypes were detected in ILIs samples in Mianyang, which belonged to three genotypes, namely HRV-A (12 strains), HRV-B (5 strains) and HRV-C (1 strain).Conclusions:HRV was one of the pathogens of ILIs cases in Mianyang during 2021—2022, with HRV-A types as the dominant strains.

Objective:To investigate the etiology of hand, foot and mouth disease (HFMD) in Mianyang city in 2022, and to analyze the genetic characteristics of coxsackievirus A6.Methods:Pharyngeal swabs were collected from patients with HFMD in Mianyang city in 2022. Real-time fluorescence quantitative PCR was used to detect enteroviruses in the samples. Part of the VP1 gene in enterovirus-positive samples was amplified by nested PCR using enterovirus typing primers to further identify the viral types. The VP1 coding region of all CVA6-positive samples and the whole genome of some samples were amplified and sequenced by PCR. The endemic strain in Mianyang city was analyzed for phylogeny, gene homology, amino acid variation and genetic recombination.Results:A total of 151 pharyngeal swabs were collected, and 104 enterovirus-positive samples were detected by real-time fluorescence quantitative PCR, with an overall detection rate of 68.88% (104/151). The typing results showed that there were 77 cases of CVA6 infection, with a positive rate of 50.99% (77/151). The full-length VP1 genes of 77 CVA6 strains were amplified, sequenced, and successfully spliced, and phylogenetic analysis showed that all 77 strains were of the D3 genotype. There were multiple amino acid variant sites in the prevalent strains in Mianyang city compared with the reference strain. Twenty whole genome sequences were amplified, sequenced, and successfully spliced, and homology analysis showed that the nucleotide homology between the 20 positive sequences ranged from 97.0% to 99.9%. Phylogenetic tree and recombination analysis showed that no recombination occurred in the coding regions of the epidemic strains in this study.Conclusions:The predominant pathogen causing HFMD in Mianyang city in 2022 is CVA6 D3 subtype, which is consistent with the national epidemic in 2022.

Objective:A mouse model of pancreatitis induced by coxsackievirus B3 (CVB3) was established. The pathological change of pancreas and the infiltration of Th17/Treg cells were observed.Methods:The BALB/c mice were inoculated intraperitoneally with CVB3 to induce acute viral pancreatitis model. Then the pathological changes of pancreas were observed by HE staining; the viral RNA load and relative expression of cytokines (IFN-γ, IL-6 and IL-17) mRNA were detected by q-PCR; the proportion of infiltrated CD45 + CD3 + T cells, CD4 + and CD8 + T cells, Th17 and Treg cells in the pancreas was determined by flow cytometry. Results:Three days after CVB3 infection, the viral RNA load in pancreas was the highest (0.96±0.18) and gradually decreased with prolongation of infection. Compared with the 3 dpi group, the viral RNA load in pancreas was decreased (0.96±0.18 vs. 0.62±0.14) at 7 dpi, but there was no statistically significant difference. In addition, the infiltration of immune cell in pancreas increased significantly after 7dpi and the pathological score >2. The percent of infiltrated Th17 cells (1.05±0.21 vs. 22.13±5.79) and Treg cells (3.11±0.78 vs. 8.25±1.30) among CD4 + T cells significantly increased after infection (P<0.05), and the Th17/Treg also increased (P<0.01). Compared with the control group, the relative mRNA expression of IFN-γ (1.05±0.23 vs. 672.6±47.67), IL-6 (1.00±0.38 vs. 68.28±4.57), and IL-17 (1.01±0.11 vs. 54.15±7.94) in pancreas increased at 7 days after CVB3 infection ( P<0.01). Conclusions:The infiltration of Th17/Treg cells and the expression of related cytokines related cytokines IL-6 and IL-17 mRNA were upregulated in pancreas, which promoted the process of CVB3-induced pancreatitis.

Objective:To analyze the epidemiological characteristics and genotypes of human rhinovirus (HRV) in patients with upper respiratory tract infection in Qingdao in the winter of 2020.Methods:Throat swab samples were collected from 101 patients with upper respiratory tract infection in Qingdao from November 2020 to January 2021. Quantitative PCR was used to detect 15 common respiratory viruses in the samples. HRV-positive samples were further analyzed with RT-PCR to amplify and sequence HRV VP4/VP2 gene. A phylogenetic tree was constructed based on the sequencing results and homology analysis was conducted.Results:Six common respiratory viruses were detected in the 101 patients. Thirty-four cases (34/101, 33.66%) were single pathogen infection and two cases were multiple infection (2/101, 1.98%). The positive rate of HRV was the highest (21.78%, 22/101). Twenty HRV VP4/VP2 sequences were successfully amplified. Phylogenetic analysis showed that there were 16 strains of HRV-A subtype and four strains of HRV-C subtype and 14 serotypes were involved.Conclusions:HRV was one of the leading viral pathogens causing upper respiratory tract infection in Qingdao in the winter of 2020 and the predominant subtype was HRV-A.

Objective To investigate the relationship between mtND4 point mutation in sperms and asthenospermia. Methods Fifty-six asthenospermia cases and 44 control cases were collected using the WHO criterion for defining asthenospermia, the regions of mtND4 gene were amplified by using PCR of 3 pairs primers. Consequently, the point mutation, missense mutation and multiple single nucleotide polymorphisms (SNP) were analyzed by employing sequencing technology and bioinformatics tools. Results Six mutations never before identified were found. The frequency of single point mutation T10873C and T11944C in the control group were significantly higher than those in the asthenospermia group (P＜0.05). Eight cases involved T10873C or T11944C among the 10 cases in control groups with missense mutations were found. But, there were only 2 cases with such mutation in the 10 asthenospermia cases with missense mutations (P＜0.05). The previous 20 cases of missense mutations can be described as either multiple SNP group (with T10873C or T11944C) or nonmultiple SNP group. The percentage of a range and a plus b range of multiple SNP group of sperm was significantly higher than the non-multiple SNP group(P＜0.05). Conclusions mtND4 gene mutation, especially the missense mutation may induce loss of sperm motility. The mutations of T10873C and T11944C may be useful for sperm motility or counteract the influence for the sperm motility caused by these harmful mutations.