AimsThe goals of this paper were to evaluate the differentiation of bone marrow mesenchymal stem cells (BMSCs) into hepatocyte-like cells in vitro, and to determine whether stem cells can migrate and plant into the liver with portal hypertension accompanied by the end-stage of liver disease. MethodsBMSCs were isolated from rats and amplified with hepatocyte growth factor (HGF) and fibroblast growth factor-4 (FGF-4). The expression of alpha-fetoprotein (AFP), cytokeratin 18 (CK-18), and albumin (ALB) was detected by immunofluorescence in induced cells. Rats were randomly divided into experimental (with common bile duct ligation) and control groups. After injection of fluorescence labeled cells, cell distribution was observed under a fluorescence microscope. The integrated optical density (IOD) and cell distribution scores were evaluated using Image-Pro Plus 6.0 software. The portal pressure was measured before the rats were killed. ResultsAfter being induced with HGF and FGF-4, the Golgi apparatus, endoplasmic reticulum, ribosomes, and mitochondria all significantly increased in the fifth generation cells. Immunofluorescent analysis showed that the induced cells expressed AFP, CK-18, and ALB. BMSCs were stained by CM-Dil, and the labeling rate was as high as 95.5%. The portal pressure in experimental group was much higher than that of the control group (18.04±2.35 vs. 9.75±1.40cm H2O p<0.01). The IOD of transplanted cells in the experimental group was also significantly higher than that of the control group (11.30±2.09×105 vs. 2.93±0.88×105, p<0.01). In addition, the cell distribution score in the experimental group was lower than that of the control group (1.99±0.36 vs. 2.36±0.27, P<0.05). ConclusionsThe combination of HGF and FGF-4 induces the differentiation of BMSCs into hepatocyte-like cells, which express AFP, CK-18, and ALB. In addition, the recruitment of BMSCs (after transplantation in the spleen) was improved in rats with portal hypertension.

Background Noroviruses (NoVs) are considered an important cause of acute gastroenteritis (AGE) across all age groups, especially in children under five years of age. We investigated the epidemiology of noroviruses in outpatient children from the Children’s Hospital of Fudan University in Shanghai, China. Methods Stool specimens were collected between January 2012 and December 2017 from 1433 children under five years of age with acute gastroenteritis. All samples were analysed by conventional reverse transcription-polymerase chain reaction (RT-PCR) for genogroup II NoVs amplifying both the RNA-dependent RNA polymerase (RdRp) and partial capsid genes. The Norovirus Genotyping Tool v.2.0 (https://www.rivm.nl/mpf/typingtool/norovirus/) was used for genotyping the strains, and phylogenetic analyses were conducted by MEGA 6.0. Results From 2012 to 2017, GII NoVs were detected in 15.4% (220/1433) of the samples, with the highest detection rate in children aged 7-12 months (19.2%, 143/746). The seasons with the highest prevalence of GII NoVs infection were autumn and winter . Based on genetic analysis of RdRp, GII.Pe (74.5%%, 137/184) was the most predominant RdRp genotype from 2013 to 2017, while GII.P4 played a dominant role in 2012 (55.6%, 21/36). Among the capsid genotypes, the most prevalent NoV genotype from 2012 to 2017 was GII.4 (73.6%, 162/220). On the basis of genetic analysis of RdRp and capsid sequences, the strains were clustered into 19 RdRp/capsid genotypes, and 12 of them were discordant, such as GII.Pe/GII.4-Sydney_2012, GII.P12/GII.3, GII.P7/GII.6, GII.Pe/GII.3, and GII.P16/GII.2. Starting with 2013, GII.Pe/GII.4-Sydney_2012 had completely replaced the pandemic GII.P4-2006b/GII.4-2006b subtype and was detected in children across all age groups. Conclusions The present study shows high detection rates and the genetic diversity of circulating NoV GII genotypes in paediatric AGE samples from Shanghai. The findings emphasize the importance of continuous molecular surveillance of emerging NoV strains.

Background: The multifaceted public health interventions taken during COVID-19 epidemic not only decrease the spreading of the SARS-CoV-2, but have impact on the prevalence of other viruses. This study aimed to explore the prevalence of common respiratory viruses among hospitalized children with lower respiratory tract infections (LRTIs) in China during the COVID-19 pandemic.Methods: Respiratory specimens were obtained from children with LRTIs at children’s hospital of Fudan University for detection of respiratory syncytial virus (RSV), adenovirus (ADV), parainfluenza virus (PIV) 1 to 3, influenza virus A (FluA), influenza virus B (FluB), human metapneumovirus (MPV) and rhinovirus (RV). The data were analyzed and compared between the year of 2020 (COVID-19 pandemic) and 2019 (before COVID-19 pandemic).Results: A total of 7107 patients were enrolled, including 4600 patients in 2019 and 2507 patients in 2020. Compared with 2019, we observed an unprecedented reduction of RSV, ADV, FluA, FluB, and MPV infections in 2020, despite of reopening of schools in June, 2020. However, The RV infection was significantly increased in 2020 and a sharp increase was observed especially after reopening of schools. Besides, the PIV infection showed resurgent characteristic after September of 2020. The mixed infections were significantly less frequent in 2020 compared with the year of 2019.Conclusions: The public health interventions during the COVID-19 pandemic have great impact on the prevalence of common respiratory viruses in China. Yet, we do need to be cautious for a possible resurgence and the resurgence may not follow the usual seasonal patterns such as RV and PIV, as COVID-19 restrictions are ongoing eased.

An unprecedented surge of Omicron infections appeared nationwide in China in December 2022 after the adjustment of COVID-19 response policy. In this study, we report the clinical and virological characteristics of SARS-CoV-2 Omicron BA.5 infections among children in Shanghai during the outbreak in late December 2022. We sequenced the 64 SARS-CoV-2 positive samples obtained from hospitalized children. The genomic monitoring revealed that the current outbreak was driven by the BA.5.2.48 and BF.7.14 subvariants. Additionally, children with BA.5.2.48 infection were more frequently observed to experience vomiting/diarrhea compared to those with BF.7.14 infection. The high-frequency unique non-synonymous mutations were present in BA.5.2.48 (N: Q241K) and BF.7.14 (nsp2: V94I, nsp12: L247F, S: C1243F, ORF7a: H47Y) with respect to their parental lineages. Of these mutations, C1243F mutation in S protein, L247F mutation in nsp12, and H47Y mutation in ORF7a protein were predicted to have a deleterious effect on the protein function. Besides, H47Y mutation was also found to increase the stability of ORF7a protein. Therefore, attention should be paid to these specific mutations, especially for H47Y mutation, which could serve as a viral immune escape strategy due to the potential immunomodulatory ability of the ORF7a protein. Continuous genomic monitoring and clinical manifestation assessments of the emerging variants will be crucial for effective responses to the ongoing COVID-19 pandemic.

Background Noroviruses are considered the important causes of acute gastroenteritis (AGE) across all age groups especially in children under five years. We investigated the prevalence and molecular epidemiology of norovirus in outpatient children from Children’s Hospital of Fudan University in Shanghai, China. Methods A total of 1433 stool specimens were collected from children under five years with acute gastroenteritis between January 2012 and December 2017. All the samples were analyzed by conventional reverse transcription-polymerase chain reaction (RT-PCR) for genogroup II targeting both the RNA-dependent RNA polymerase (RdRp) and partial capsid genes. Norovirus Genotyping Tool v.2.0 (https://www.rivm.nl/mpf/typingtool/norovirus/) was used for genotyping strains, and phylogenetic analyses were conducted by MEGA 6.0. Results During 2012 to 2017, NoVs were detected in 15.4% (220/1433) of the samples, with high detection rate in children aged 7-12 months (19.2%, 143/746) and in September (27.7%, 33/119). Based on genetic analysis of RdRp, GII.Pe (74.5%%, 137/184) was the most predominating RdRp genotype from 2013 to 2017 while GII.P4 played a dominant role in 2012 (55.6%, 21/36). The most prevalent NoVs genotype was GII.4 (73.6%, 162/220) during 2012 to 2017 among the capsid genotypes. According to genetic analysis of RdRp and capsid sequences, the strains were clustered into 19 RdRp/capsid genotypes, and 12 of them were discordant RdRp and capsid genotypes, such as GII.Pe/GII.4-Sydney_2012, GII.P12/GII.3, GII.P7/GII.6, GII.Pe/GII.3, GII.P16/GII.2. GII.Pe/GII.4-Sydney_2012 was completely instead of the pandemic of GII.P4-2006b/GII.4-2006b since 2013 and distributed across all age groups in children. Conclusions The present study shows high detection rates and genetic diversity of circulating NoVs genotypes in paediatric AGE samples from Shanghai. The findings emphasize the importance of continuous molecular surveillance of emerging NoVs strains.