Genotype analysis of rotaviruses isolated from children during a phase III clinical trial with the hexavalent rotavirus vaccine in China

The oral hexavalent live human-bovine reassortant rotavirus vaccine(RV6)developed by Wuhan Institute of Biological Products Co.,Ltd(WIBP)has finished a randomized,placebo-controlled phase III clinical trial in four provinces of China in 2021.The trail demonstrated that RV6 has a high vaccine efficacy against the prevalent strains and is safe for use in infants.During the phase III clinical trial(2019–2021),200 rotavirus-positive fecal samples from children with RV gastroenteritis(RVGE)were further studied.Using reverse transcription-polymerase chain reaction and high-throughput sequencing,VP7 and VP4 sequences were obtained and their genetic characteristics,as well as the differences in antigenic epitopes of VP7,were analyzed in detail.Seven rotavirus genotypes were identified.The predominant rotavirus genotype was G9P[8](77.0%),followed by prevalent strains G8P[8](8.0%),G3P[8](3.5%),G3P[9](1.5%),G1P[8](1.0%),G2P[4](1.0%),and G4P[6](1.0%).The amino acid sequence identities of G1,G2,G3,G4,G8,and G9 genotypes of isolates compared to the vaccine strains were 98.8%,98.2%–99.7%,88.4%–99.4%,98.2%,94.2%–100%,and 93.9%–100%,respectively.Notably,the vaccine strains exhibited high similarity in amino acid sequence,with only minor differences in antigenic epitopes compared to the Chinese endemic strains.This supports the potential application of the vaccine in preventing diseases caused by rotaviruses.

Evaluation of the infectivity,gene and antigenicity persistence of rotaviruses by free chlorine disinfection

The effects of free chlorine disinfection of tap water and wastewater effluents on the infectivity, gene integrity and surface antigens of rotaviruses were evaluated by a bench-scale chlorine disinfection experiments. Plaque assays, integrated cell culture-quantitative RT- PCR （ICC-RT-qPCR）, RT-qPCR, and enzyme-linked immunosorbent assays （ELISA）, respectively, were used to assess the influence of the disinfectant on virus infectivity as well as genetic and antigenic integrity of simian rotavirus SA11 as a surrogate for human rotaviruses. The ICC-RT-qPCR was able to detect rotaviruses survival from chlorine disinfection at chlorine dose up to 20 mg/L （60 min contact）, which suggested a required chlorine dose of 5 folds （from 1 to 5 mg/L） higher than that indicated by the plaque assay to achieve 1.8 log10 reductions in tap water with 60 rain exposing. The VP7 gene was more resistant than the infectivity and existed at chlorine dose up to 20 mg/L （60 min contact）, while the antigencity was undetectable with chlorine dose more than 5 mg/L （60 min contact）. The water quality also impacted the inactivation efficiencies, and rotaviruses have a relatively higher resistant in secondary effluents than in the tap water under the same chlorine disinfection treatments. This study indicated that rotaviruses have a higher infectivity, gene and antigencity resistance to chlorine than that previously indicated by plaque assay only, which seemed to underestimate the resistance of rotaviruses to chlorine and the risk of rotaviruses in environments. Present results also suggested that re-evaluation of resistance of other waterborne viruses after disinfections by more sensitive infectivity detection method （such as ICC-RT-qPCR） may be necessary, to determine the adequate disinfectant doses required for the inactivation of waterborne viruses.

Epidemiological Surveillance: Genetic Diversity of Rotavirus Group A in the Pearl River Delta, Guangdong, China in 2019

Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals aged 28 days–85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA.Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0–1 year,and RVA is the key pathogen circulating in patients 6–10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains.Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development.

Molecular detection of viruses in Kenyan bats and discovery of novel astroviruses, caliciviruses and rotaviruses

This is the first country-wide surveillance of bat-borne viruses in Kenya spanning from 2012–2015covering sites perceived to have medium to high level bat-human interaction. The objective of this surveillance study was to apply a non-invasive approach using fresh feces to detect viruses circulating within the diverse species of Kenyan bats. We screened for both DNA and RNA viruses;specifically, astroviruses(AstVs), adenoviruses(ADVs), caliciviruses(CalVs), coronaviruses(CoVs), flaviviruses, filoviruses, paramyxoviruses(PMVs), polyomaviruses(PYVs) and rotaviruses.We used family-specific primers, amplicon sequencing and further characterization by phylogenetic analysis. Except for filoviruses, eight virus families were detected with varying distributions and positive rates across the five regions(former provinces) studied. AstVs(12.83%), CoVs(3.97%), PMV(2.4%), ADV(2.26%), PYV(1.65%), CalVs(0.29%), rotavirus(0.19%) and flavivirus(0.19%). Novel CalVs were detected in Rousettus aegyptiacus and Mops condylurus while novel Rotavirus-A-related viruses were detected in Taphozous bats and R. aegyptiacus. The two Rotavirus A(RVA) strains detected were highly related to human strains with VP6 genotypes I2 and I16. Genotype I16 has previously been assigned to human RVA-strain B10 from Kenya only, which raises public health concern, particularly considering increased human-bat interaction.Additionally, 229E-like bat CoVs were detected in samples originating from Hipposideros bats roosting in sites with high human activity. Our findings confirm the presence of diverse viruses in Kenyan bats while providing extended knowledge on bat virus distribution. The detection of viruses highly related to human strains and hence of public health concern, underscores the importance of continuous surveillance.

Gastrointestinal tract and viral pathogens

Viral gastroenteritis is the most common viral illness that affects the gastro-intestinal(GI)tract,causing inflammation and irritation of the lining of the stomach and intestines.Common signs and symptoms associated with this condition include abdominal pain,diarrhea,and dehydration.The infections commonly involved in viral gastroenteritis are rotavirus,norovirus,and adenovirus,which spread through the fecal-oral and contact routes and cause non-bloody diarrhea.These infections can affect both immunocompetent and immunocompromised individuals.Since the pandemic in 2019,coronavirus gastroenteritis has increased in incidence and prevalence.Morbidity and mortality rates from viral gastroenteritis have declined significantly over the years due to early recognition,treatment with oral rehydration salts,and prompt vaccination.Improved sanitation measures have also played a key role in reducing the transmission of infection.In addition to viral hepatitis causing liver disease,herpes virus,and cytomegalovirus are responsible for ulcerative GI disease.They are associated with bloody diarrhea and commonly occur in im-munocompromised individuals.Hepatitis viruses,Epstein-Barr virus,herpesvirus 8,and human papillomavirus have been involved in benign and malignant diseases.This mini review aims to list different viruses affecting the GI tract.It will cover common symptoms aiding in diagnosis and various important aspects of each viral infection that can aid diagnosis and management.This will help primary care physicians and hospitalists diagnose and treat patients more easily.

Neonatal erythema multiforme associated with a rotavirus infection:A case report

BACKGROUND Erythema multiforme(EM)is an extremely rare condition in neonates,and studies suggest its association with certain infections and neonatal vaccinations;however,few specific etiological agents have been identified.Rotavirus,a common pathogenic gastrointestinal virus in the neonatal period that is preventable via vaccination,has not been identified as a possible etiology.We report the case of a neonate who was referred for skin lesions presenting as EM,where a meticulous workup identified rotavirus as the sole causative agent.CASE SUMMARY A 14-day-old male infant was admitted to our hospital with a 1-day history of skin lesions.No medical history or medication intake was recorded.Except for the complaint of skin lesions,the caregivers denied any abnormal symptoms.Multiple tests,including routine laboratory evaluations,were performed to identify the cause of skin lesions.Serological tests for Immunoglobulin M for Toxoplasma,Rubella,Cytomegalovirus,Herpes Simplex Virus,and Epstein-Barr virus viral-capsid antigen were all negative.Multiple polymerase chain reaction(PCR)tests for respiratory viruses and bacterial pathogens were negative(including the severe acute respiratory syndrome coronavirus 2).Multiple PCR tests for gastrointestinal viruses and bacterial pathogens demonstrated evidence of rotavirus infection.No growth was reported in the blood and urine cultures.The patient received intravenous fluids for hydration;meanwhile,no other medications were prescribed.The lesions improved rapidly without specific treatment,and full recovery was achieved within a week.CONCLUSION The possibility of rotavirus,a major cause of pediatric gastrointestinal infections,being a trigger for neonatal EM should be considered.

Clinical factors predicting rotavirus diarrhea in children:A crosssectional study from two hospitals

BACKGROUND Rotavirus is still a significant contributing morbidity and mortality in pediatric patients.AIM To look at clinical signs and symptoms and laboratory findings that can predict rotavirus gastroenteritis compared to non-rotavirus gastroenteritis.METHODS This was a cross-sectional study with medical records obtained from December 2015 to December 2019.Inclusion criteria for this study include all hospitalised pediatric patients(0-18 years old)diagnosed with suspected rotavirus diarrhea.The receiver operating curve and Hosmer-Lemeshow test would be used to assess the final prediction findings'calibration(goodness of fit)and discrimination performance.RESULTS This study included 267 participants with 187(70%)rotavirus-diarrhea cases.The patients were primarily male in both rotavirus(65.2%)and non-rotavirus(62.5%)groups.The median age is 1.33 years old(0.08-17.67 years old).Multivariate analysis shows that wet season(OR_(adj)=2.5;95%CI:1.3-4.8,Padj=0.006),length of stay(LOS)≥3 days(OR_(adj)=5.1;95%CI:1.4-4.8,Padj=0.015),presence of abdominal pain(OR_(adj)=3.0;95%CI:1.3-6.8,Padj=0.007),severe dehydration(OR_(adj)=2.9;95%CI:1.1-7.9,Padj=0.034),abnormal white blood cell counts(OR_(adj)=2.8;95%CI:1.3-6.0,Padj=0.006),abnormal random blood glucose(OR_(adj)=2.3;95%CI:1.2-4.4,Padj=0.018)and presence of fecal leukocytes(OR_(adj)=4.1,95%CI:1.7-9.5,Padj=0.001)are predictors of rotavirus diarrhea.The area under the curve for this model is 0.819(95%CI:0.746-0.878,P value<0.001),which shows that this model has good discrimination.CONCLUSION Wet season,LOS≥3 d,presence of abdominal pain,severe dehydration,abnormal white blood cell counts,abnormal random blood glucose,and presence of fecal leukocytes predict rotavirus diarrhea.

树突状细胞与轮状病毒相互作用机制研究进展

轮状病毒（Rotavirus,RV）属于呼肠孤病毒科轮状病毒属成员,是引起婴幼儿和其他幼龄动物腹泻的主要病原之一,全世界每年约有400 000名儿童因感染此病毒而死亡（[1]）。RV感染已成为全球性的健康问题,

Inflammatory and oxidative stress in rotavirus infection

Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and various cell surface molecules. The entry mechanisms seem to involve the contribution of cellular molecules having binding, chaperoning and oxido-reducing activities. It appears to be that the receptor usage and tropism of rotaviruses is determined by the species, cell line and rotavirus strain. Rotaviruses have evolved functions which can antagonize the host innate immune response, whereas are able to induce endoplasmic reticulum(ER) stress, oxidative stress and inflammatory signaling. A networking between ER stress, inflammation and oxidative stress is suggested, in which release of calcium from the ER increases the generation of mitochondrial reactive oxygen species(ROS) leading to toxic accumulation of ROS within ER and mitochondria. Sustained ER stress potentially stimulates inflammatory response through unfolded protein response pathways. However, the detailed characterization of the molecular mechanisms underpinning these rotavirus-induced stressful conditions is still lacking. The signaling events triggered by host recognition of virusassociated molecular patterns offers an opportunity for the development of novel therapeutic strategies aimed at interfering with rotavirus infection. The use of N-acetylcysteine, non-steroidal anti-inflammatory drugs and PPARγ agonists to inhibit rotavirus infection opens a new way for treating the rotavirus-induced diarrhea and complementing vaccines.

轮状病毒疫苗研究进展

轮状病毒（Rotavirus,RV）是引起多种幼龄动物以及婴幼儿腹泻的重要病原体。轮状病毒最早是Mebus在1969年从犊牛粪便中发现的,1973年澳大利亚科学家Bishop等在患有严重腹泻婴儿的十二指肠黏膜及粪便中发现了一种新的病毒粒子。在非洲和亚洲的撒哈拉以南地区,据调查超过三分之一的婴幼儿腹泻及胃肠炎疾病由轮状病毒引起,每年导致50万-60万婴幼儿死亡。

小鼠轮状病毒感染

轮状病毒(Rotavirus)是各种幼龄动物非菌性腹泻的主要病原之一。小鼠的流行性腹泻就是由于它所引起的。此外,人、绵羊、山羊、羚羊、幼驹、鹿、犊牛、兔、猴、猪、犬、鸡、火鸡,鸭等都有很多关于发生轮状病毒感染的报道。也曾在棕熊、豚鼠检测到特异性抗病毒抗体。小鼠轮状病毒在鼠群中感染很普遍,特别是在第一胎仔鼠中,且死亡率高,给生产带来很大的损失。此病易与由其它病毒和细菌引起的腹泻相混淆。现就它的一些特性做一概述。一、形态、理化学特性及分类: 1947年Cheever等人第一次对小鼠流行性腹泻(EDIM)做了报道。电镜检查可以观察到两种形态的病毒颗粒:一种是有外衣壳的完整病毒粒子,直径为75—80nm,一般只有在用回肠做直接印片时才能观察到;

河南省人轮状病毒核酸区带电泳分析研究

轮状病毒(RV)是世界范围内儿童、特别是6月—2岁婴幼儿腹泻的重要病因。近年来发现它同样是成人腹泻的主要病因之一。按其血清学特征,已发现了四个血清群人轮状病毒(HRV),但进行不同血清群 RV 肠炎流行病学调查。

乳鼠流行性腹泻研究概况

乳鼠流行性腹泻(EDIM)是开放饲养小鼠的乳鼠常见疾病,早在1947年,Cheever等首次系统地研究了实验乳鼠所发生的流行性腹泻。其特点为2周龄乳鼠发生急性腹泻,患病率高,传染性强,但死亡率相对较低。1957年Kraft认为本病致病原是病毒。1963年又经Adams用电镜观察证实,起名为乳鼠流行性腹泻病毒。病毒形态与引起牛、猴、猪和羊等腹泻的轮状病毒(Rotavirus,RV)相似,以后证明它与这些RV有血清学关系,定名为小鼠轮状病毒(MRV)。由于其基因组由双股RNA组成,归为呼肠孤病毒科,轮状病毒属。最近,有资料表明,我国也有许多品系乳鼠发生由MRV引起的EDIM。一、病原学MRV形态为典型RV。完整MRV直径75—80nm,缺乏外膜的不完整MRV直径约为65nm左右。它在56℃或60℃半小时内仍具感染性。

Prevalence and Genotypes of Rotavirus A and Human Adenovirus among Hospitalized Children with Acute Gastroenteritis in Fujian, China, 2009-2017

Gastroenteritis is an infectious diarrhea that has been considered as an important cause of hospitalizations and death in children aged < 5 years, particularly in developing countries. Unsanitary water, contaminated food, poor hygiene, and inadequate disposal of waste and feces are all risk factors for gastroenteritis, resulting in the higher incidence in developing countries. Gastroenteritis is generally caused by viral infections, among which rotavirus (RV) infections have been reported to be the most common, especially among young children aged < 5 years with acute gastroenteritis in Asia and Africa[1]. Other viruses associated with acute gastroenteritis include human Adenovirus (HAdV), Norovirus, Sapovirus (SaV), human Astrovirus (HAstV), and Aichi virus. Recent research has reported that adenovirus types 40 and 41, belonging to species F, cause gastroenteritis and were therefore termed as enteric adenoviruses. In addition, non-enteric HAdV species such as A, B, C, and D have been associated with diarrheal.

Efficacy of Lactobacillus rhamnosus GG in treatment of acute pediatric diarrhea: A systematic review with meta-analysis

BACKGROUND Diarrhea is a major infectious cause of childhood morbidity and mortality worldwide.In clinical trials,Lactobacillus rhamnosus GG ATCC 53013(LGG)has been used to treat diarrhea.However,recent randomized controlled trials(RCTs)found no evidence of a beneficial effect of LGG treatment.AIM To evaluate the efficacy of LGG in treating acute diarrhea in children.METHODS The EMBASE,MEDLINE,PubMed,Web of Science databases,and the Cochrane Central Register of Controlled Trials were searched up to April 2019 for metaanalyses and RCTs.The Cochrane Review Manager was used to analyze the relevant data.RESULTS Nineteen RCTs met the inclusion criteria and showed that compared with the control group,LGG administration notably reduced the diarrhea duration[mean difference(MD)-24.02 h,95%confidence interval(CI)(-36.58,-11.45)].More effective results were detected at a high dose≥1010 CFU per day[MD-22.56 h,95%CI(-36.41,-8.72)]vs a lower dose.A similar reduction was found in Asian and European patients[MD-24.42 h,95%CI(-47.01,-1.82);MD-32.02 h,95%CI(-49.26,-14.79),respectively].A reduced duration of diarrhea was confirmed in LGG participants with diarrhea for less than 3 d at enrollment[MD-15.83 h,95%CI(-20.68,-10.98)].High-dose LGG effectively reduced the duration of rotavirus-induced diarrhea[MD-31.05 h,95%CI(-50.31,-11.80)]and the stool number per day[MD-1.08,95%CI(-1.87,-0.28)].CONCLUSION High-dose LGG therapy reduces the duration of diarrhea and the stool number per day.Intervention at the early stage is recommended.Future trials are expected to verify the effectiveness of LGG treatment.

Lentinan administration alleviates diarrhea of rotavirus-infected weaned pigs via regulating intestinal immunity

Background:Lentinan(LNT)may regulate many important physiological functions of human and animals.This study aimed to verify whether LNT administration could relieve diarrhea via improving gut immunity in rotavirus(RV)-challenged weaned pigs.Methods:Twenty-eight weaned pigs were randomly fed 2 diets containing 0 or 84 mg/kg LNT product for 19 d(n=14).RV infection was executed on d 15.After extracting polysaccharides from LNT product,its major monosaccharides were analyzed.Then,LNT polysaccharide was used to administrate RV-infected IPEC-J2 cells.Results:Dietary LNT supplementation supported normal function of piglets even when infected with RV,as reflected by reduced growth performance loss and diarrhea prevalence,and maintained gut immunity(P<0.05).The polysaccharide was isolated from LNT product,which molecular weight was 5303 Da,and major monosaccharides included glucose,arabinose and galactose.In RV-infected IPEC-J2 cells,this polysaccharide significantly increased cell viability(P<0.05),and significantly increased anti-virus immunity via regulating pattern recognition receptors and host defense peptides(P<0.05).Conclusion:Those results suggest that LNT administration increases the piglets’resistance to RV-induced stress,likely by supporting intestinal immunity.

Treatment of rotaviral gastroenteritis with Qiwei Baizhu powder

AIM To observe the effects of Qiwei Baizhu Powder ( QWBZP) on rotaviral gastroenteritis in children and in animal models.``METHODS Enrolled patients were divided into two groups, and one group was treated with oral rehydration solution(ORS) and the other treated with oral liquid of QWBZP. Neonate mice were orally infected with 50 μLrotavirus suspension (4 × l0s PFU/mL) and treated with ORS or oral liquid of QWBZP, respectively.``RESULTS Eighty-three cases of rotaviral gastroenteritis treated with QWBZP revealed a better efficacy than that treated with ORS (x2 - 10.8T, P<0.05). The contents of sodium and glucose as well as number of patients with positive human rotavirus antigen in stool in QWBZP group were all less than that in ORS group. In animal models,QWBZP was found effective in treating rotavirus gastroenteritis in neonate NIH mice, as compared with control groups. In QWBZP group, the mortality of infected mice was decreased by 73.3%, the body weight of infected mice was increased, the contents of sodium and glucose as well as number of mice with positive rotavirus antigen in feces were significantly reduced, and the pathological changes such as damage of small intestinal mucosa and villi were also obviously alleviated.``CONCLUSION QWBZP has effects on improving the absorptive function of small intestine, shortening the duration of diarrhea and rotavirus shedding from stool and alleviating the pathological changes of small intestine induced by rotavirus.

Expression of NF-kappaB in rotavirus-induced damage to the liver and biliary tract in neonatal mice

BACKGROUND: Biliary atresia, the etiology of which still remains unclear, occurs exclusively in newborns and most are infected with rotavirus. In this study, we aimed to investigate the histopathological patterns of different kinds of rotavirus in the liver and biliary tract of neonatal mice and the expression of NF-kappa B in the liver and biliary tract of infected mice. METHODS: Twenty-three adult mice (8 were male and 15 female) were divided into 8 breeding pairs, and each pair (I male and 2 females) was housed in a cage in a laminar flow hood. Newborn mice, 24-48 hours old were randomly divided into A, B and C groups. The A and B groups were respectively inoculated with MMU18006 and SA11 rotavirus through the intraperitoneal route, while group C as blank control was only inoculated with culture medium. The liver was dissected after 5, 10, 15, 21 and 28 days; the weight of each mouse and the histopathological patterns in the liver were recorded. The expression of NF-kappa B in the liver and intrahepatic bile ducts was detected by immunohistochemical staining and the expression intensity was analyzed with a GT-2 imaging instrument. RESULTS: The average increase in weight of infected mice was significantly slower than that of the normal control, while the growth rate of group A (injected with MMU18006 rotavirus) was slower than that of group B (SA11 rotavirus). In infected mice, the acute and chronic inflammation of liver and intra- and extra-hepatic bile ducts was more significant in group A. Stenosis was found in most intrahepatic bile ducts, and sporadically in extrahepatic bile ducts. The expression of NF-kappa B in infected mice was dramatically higher than that of the normal control, while the expression in group A was higher than in group B. CONCLUSIONS: Significant damage to the liver and biliary tract of neonatal mice can be induced by inoculating MMU18006 rotavirus through the intraperitoneal route, which is very similar to the pathology of biliary atresia in the newborn human. Similar inoculation with SA11 rotavirus can only result in moderate impairment that disappears quickly. The difference of pathogenicity between the two rotaviruses may depend on their differing capacities to increase the expression of NF-kappa B in the liver and biliary tract.

Acute effects of rotavirus and malnutrition on intestinal barrier function in neonatal piglets

AIM: To investigate the effect of protein-energy malnutrition on intestinal barrier function during rotavirus enteritis in a piglet model.METHODS: Newborn piglets were allotted at day 4 of age to the following treatments:(1) full-strength formula(FSF)/noninfected;(2) FSF/rotavirus infected;(3) half-strength formula(HSF)/noninfected;or(4) HSF/rotavirus infected.After one day of adjustment to the feeding rates,pigs were infected with rotavirus and acute effects on growth and diarrhea were monitored for 3 d and jejunal samples were collected for Ussingchamber analyses.RESULTS: Piglets that were malnourished or infected had lower body weights on days 2 and 3 post-infection(P < 0.05).Three days post-infection,marked diarrhea and weight loss were accompanied by sharp reductions in villus height(59%) and lactase activity(91%) and increased crypt depth(21%) in infected compared with non-infected pigs(P < 0.05).Malnutrition also increased crypt depth(21%) compared to full-fed piglets.Villus:crypt ratio was reduced(67%) with viral infection.There was a trend for reduction in transepithelial electrical resistance with rotavirus infection and malnutrition(P = 0.1).3H-mannitol flux was significantly increased(50%;P < 0.001) in rotavirus-infected piglets compared to non-infected piglets,but there was no effect of nutritional status.Furthermore,rotavirus infection reduced localization of the tight junction protein,occludin,in the cell membrane and increased localization in the cytosol.CONCLUSION: Overall,malnutrition had no additive effects to rotavirus infection on intestinal barrier function at day 3 post-infection in a neonatal piglet model.

Downregulation of Hes1 expression in experimental biliary atresia and its effects on bile duct structure

AIM To analyze the expression and function of the notchsignaling target gene Hes1 in a rhesus rotavirusinduced mouse biliary atresia model. METHODS The morphologies of biliary epithelial cells in biliary atresia patients and in a mouse model were examined by immunohistochemical staining. Then, the differential expression of Notch signaling pathway-related molecules was investigated. Further, the effects of the si RNAmediated inhibition of Hes1 expression were examined using a biliary epithelial cell 3 D culture system.RESULTS Both immature(Ep CAM+) and mature(CK19+) biliary epithelial cells were detected in the livers of biliary atresia patients without a ductile structure and in the mouse model with a distorted bile duct structure. The hepatic expression of transcripts for most Notch signaling molecules were significantly reduced on day 7 but recovered to normal levels by day 14, except for the target molecule Hes1, which still exhibited lower m RNA and protein levels. Expression of the Hes1 transcriptional co-regulator, RBP-Jκ was also reduced. A 3 D gel culture system promoted the maturation of immature biliary epithelial cells, with increased expression of CK19+ cells and the formation of a duct-like structure. The administration of Hes1 si RNA blocked this process. As a result, the cells remained in an immature state, and no duct-like structure was observed.CONCLUSION Our data indicated that Hes1 might contribute to the maturation and the cellular structure organization of biliary epithelial cells, which provides new insight into understanding the pathology of biliary atresia.