Anti-viral Effects of Urosolic Acid on Guinea Pig Cytomegalovirus In Vitro

This study examined the anti-viral effect of ursolic acid on guinea pig cytomegalovirus (GPCMV) and explored the steps of viral replication targeted by ursolic acid. Cytopathic effect assay and MTT method were employed to determine the 50% cellular cytotoxicity (CC50), 50% effective concentration (EC50) and therapeutic index (TI) with GPCMV. To investigate the specific anti-viral effect of ursolic acid at different temperatures and time points, two other medicines, ganciclovir and Jinyebaidu (JYBD), serving as controls, were studied for comparison. Our results showed that the CC50 of ganciclovir, JYBD and ursolic acid were 333.8, 3015.6, 86.7 μg/mL, respectively; EC50 of ganciclovir, JYBD and ursolic acid was 48.1, 325.5 and 6.8 μg/mL, respectively; TI of ganciclovir, JYBD and ursolic acid was 7, 9, 13, respectively. Similar with ganciclovir, ursolic acid could inhibit the viral synthesis, but did not affect the viral adsorption onto and penetration into cells. We are led to conclude that the anti-cytomegalovirus effect of ursolic acid is significantly stronger than ganciclovir or JYBD, and the cytotoxic effect of ursolic acid lies in its ability to inhibit viral synthesis.

Association of Blastocystis hominis with colorectal cancer:A systematic review of in vitro and in vivo evidences

BACKGROUND Recently,there have been several findings that showed intestinal colonisation of Blastocystis hominis(Blastocystis)as a risk factor to the worsening of colorectal cancer(CRC).However,studies have shown controversial results in the pathogenicity of Blastocystis.AIM To review systematically the evidence available on the association between CRC and Blastocystis and the prevalence of Blastocystis in CRC patients and to investigate cytopathic and immunological effects of Blastocystis in in vitro and in vivo studies.METHODS PRISMA guidelines were utilised in conducting this systematic review.Original articles published before February 2,2020 were included.PubMed,Science Direct,Scopus and Google scholar databases were searched.Manual searching was carried out to find articles missed during the online search.RESULTS Out of 12 studies selected for this systematic review,seven studies confirmed the prevalence of Blastocystis and found it to be between 2%-28%in CRC patients,whereby subtype 1 and subtype 3 were predominantly seen.A total of four studies employing in vitro human colorectal carcinoma cell line study models showed significant cytopathic and immunological effects of Blastocystis.In addition,one in vivo experimental animal model study showed that there was a significant effect of infection with Blastocystis on exacerbation of colorectal carcinogenesis.CONCLUSION Blastocystis is a commonly identified microorganism in CRC patients.These studies have provided supportive data that Blastocystis could exacerbate existing CRC via alteration in host immune response and increased oxidative damage.Future studies of CRC and Blastocystis should attempt to determine the various stages of CRC that are most likely to be associated with Blastocystis and its relationship with other intestinal bacteria.

Initiation of two ovarian cell lines from Fugu rubripes(Temminck et.Schlegel)

The ovary is an excellent system for studying stem cell renewal and differentiation, which is under the control of ovarian somatic cells. In order to understand oogenesis in Fugu rubripes （Temminck et. Schlegel） as a marine fish model of aquaculture importance, we established cell lines called TSOC 1 and TSOC2 from a juvenile ovary of this organism. TSOC1 is composed of spindle epithelial-like cells, while the other is cobblestone-like ceils. Therefore, TSOC1 and TSOC2 appear to consist of ovarian somatic cells. Growth requirement condition was investigated including temperature, concentration of FBS and pH. Significant fluorescent signals were observed after TSOC1 and TSOC2 cells were transfected with pEGFP-N3 vector, indicating its potential utility for genetic manipulation such as gene function studies. It is shown that these cell lines are effective for infection by the turbot reddish body iridovirus and flounder lymphosystis disease virus as evidenced by the appearance of cytopathic effect and virus propagation in the virus-infected cells, and most convincingly, the observation of viral particles by electron microscopy, demonstrating that TSOC1 and TSOC2 are suitable to study interactions between virus and host cells. It is believed that TSOC1 and TSOC2 will be useful tools to study sex-related events and interactions between primordial germ cells and oogonia cells during oogenesis. Therefore, establishment of ovary cell lines from Fugu rubripes seems to be significant for those research areas.

COVID-19 impact on the liver

The coronavirus disease 2019(COVID-19)pandemic imposed arestructuring of global health systems by rethinking spaces used for the care of these patients and the additions of intensive care,infectious diseases and pneumology departments.This paper provides evidence on the presence of severe acute respiratory syndrome coronavirus 2 in hepatocytes and its direct cytopathic activity,as well as the degree of liver damage due to drug toxicity,inflammation and hypoxia in COVID-19.A review of clinical trials has quantified liver damage through both pathology and biochemistry studies.Additionally,we briefly present the results of a study conducted in our clinic on 849 patients admitted for COVID-19 treatment,of which 31 patients had pre-existing chronic liver disease and 388 patients had values above the normal limit for alanine aminotransferase,aspartate aminotransferase,and total bilirubin.It was observed that patients with abnormal liver tests were significantly statistically older,had more comorbidities and had a higher percentage of unfavourable evolution(death or transfer to intensive care).The conclusion of this paper is that the main causes of liver damage are direct viral aggression,coagulation dysfunction and endothelial damage,and patients with impaired liver function develop more severe forms of COVID-19 which requires special care by a multidisciplinary team that includes a hepatologist.

Study on Antimicrobial and Antiviral Activities of Lysozyme From Marine Strain S-12-86 In Vitro

In this study, the in vitro antimicrobial and antiviral activities of the lysozyme from marine strain S-12-86 （LS） were investigated, The antimicrobial activity of LS was tested by minimum inhibition concentration （MIC） and minimum bactericidal concentration （MBC） method. The inhibiting effects of LS on pseudo rabies virus （PRV） in swine kidney cells （PK-15 ceils） were judged by cytopathogenic effect test （CPE）, The results showed LS had a broad antimicrobial spectrum against several standard strains including gram-positive bacteria, gram-negative bacteria, fungi, etc, The MIC of LS was 0.25-4.00 mg mL^-1 and its MBC was 0.25-8.00 mg mL^-1, respectively, Observation under the transmission electron microscope revealed that the cell wall of Candida albicans was distorted seriously, and the cytoplasm with many cavities was asymmetrical after being hydrolyzed by LS, The median cytotoxicity concentration （TC50） of LS was 100.0 μg mL^-1, the median effective concentration （EC50） was 0.46 μg mL^-1, and the selectivity index （TI = TC50/EC50） was 217. LS could inhibit PRV in PK-15 cells when it was added to cell culture medium at 0, 2, 4, 6, and 8 h after PK-15 cells had been infected by PRV. From the results, we concluded that LS had broad antimicrobial spectrum and good inhibiting effects on PRV,

Isolation and Identification of Porcine Epidemic Diarrhea Virus(PEDV) HLJ Strain with IPEC-J2 Cells and Phylogenetic Analysis of Its S Gene

Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resulted in tremendous economic losses to swine industry.The PEDV mainly infects small intestine of pigs,resulting in vacuolar degeneration and necrosis of mucosal epithelium.The IPEC-J2 is a pig intestine epithelial cell line,which is similar to the intestinal environment of piglets,can be used to isolate and identify the PEDV field isolates.In this study,it appeared the PEDV typical postmortem changes and histopathological lesion of degeneration and destruction of small intestine in infected piglets,and IHC identified that the PEDV distributed in the mucosa and submucosa of small intestine mostly.Furthermore,the PEDV HLJ strain was successfully isolated and characterized in the IPEC-J2 cells,and indicated that the IPEC-J2 cell line was sensitive to isolate and adapt the PEDV field strain,and could be utilized to multiply the PEDV rapidly.The S gene analysis indicated that the PEDV HLJ strain was the prevailed virus,belonged to Group 1 with attenuated virulent DR13,SC1402 and J-S2/2015 strains isolated in South Korea and China from 2014 to 2015.This study had important theoretical and practical significances on analyzing genetic variation of the PEDV,understanding the pathogenic characteristics of the virus and developing new vaccines for the PED.

Construction and in vitro Study of an E1B-Defective Adenovirus

An E1B-defective adenovirus named r1/Ad was constructed by homologous recombination. The construction, selection and propagation of recombinant virus was done in the human embryonic kidney 293 cells (HEK293). Thein vitro study demonstrated that the recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as the human glioblastoma tumor cells (U251) and human bladder tumer cells (EJ) but not in the normal cells with functional p53 such as the human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated that the U251 cells were more sensitive to the infection of r1/Ad than that of EJ cells under identical conditions. In this paper, it was found that r1/Ad could be very useful in studying thein vitro selective replication of E1B-defective adenovirus. This may help to determine the safety of using any E1B-defective adenoviruses in cancer gene therapy. Key words E1B-defective adenovirus - cytopathic effect - cancer gene therapy CLC number Q78 Foundation item: Supported by the National Natural Science Foundation of China (3988003)Biography: Xue Feng (1978-), male, Master, research direction: cancer gene therapy by recombinant virus.

ANTIVIRAL TESTS OF METHYLENE BLUE INJECTION ON VZV IN VITRO

Methylene blue injection has a stronger direct inactivation on VZV in vitro. When the injection was diluted from 116 to 1128, which was obvious (P<001 and P<005). The MIC was 1222, the IC50 was 1135 and IC90 was 177. The results of microcellculture method showed when the injection was diluted from 116 to 164, it also effectively inhibited the proliferation of VZV in WISH continuous celllines (P<001 and P<005). The MIC was 195, the IC50 was 145 and the IC90 was 121.

Isolation,Identification and Immunogenicity of a Chicken-derived Strain of Fowl Avidenovirus Type 4

In order to obtain a fowl avidenovirus type 4 strain with good immunogenicity,chicken liver tissues suspected of adenovirus infection in a chicken farm in Binzhou were treated and then inoculated to chicken liver hepatocellular carcinoma cells(LMH).The cell cultures were extracted for DNA,which was subjected to PCR identification and sequencing analysis,and animal regression test and immunogenicity test were also carried out.The results showed that one fowl avidenovirus strain was successfully isolated.The isolated strain was inoculated to LMH cells,and the first generation showed obvious cytopathic changes.The PCR identification result of the 8^(th)generation cell culture of the isolated virus strain on LMH cells was positive.The sequencing result and NCBI sequence alignment analysis showed that the isolated virus strain had the highest nucleotide similarity with fowl avidenovirus type 4,reaching 100%,indicating that the isolated strain was of fowl avidenovirus type 4.The strain could cause the death of 21-day-old SPF chickens,with a mortality rate of 100%,and could completely replicate the same symptoms as clinically infected chickens after being challenged.The three batches of oil vaccine prepared with the isolated strain had a protection rate of 100%,and the geometric mean values of serum agar expansion titers were 1∶4.6,1∶4.9,and 1∶4.6,respectively.It can be seen that the isolated virus is of fowl avidenovirus type 4 in group I,and has good immunogenicity.

Identification of Porcine Reproductive and Respiratory Syndrome Virus Inhibitors Through an Oriented Screening on Natural Products

Porcine reproductive and respiratory syndrome（PRRS） caused by porcine reproductive and respiratory syndrome virus（PRRSV） is one of the most infectious diseases in the swine industry worldwide, causing big eco- nomic losses. Vaccines are major weapons against PRRSV, however, current available vaccines have several limita- tions. Developing chemical drugs as alternatives is required. On the basis of traditional medical knowledge, we pur- posely selected 15 natural products originated from Chinese herbs with anti-infectious effects. Their antiviral activi- ties were evaluated by PRRSV-indueed cytopathic effect（CPE） on MARC-145 cells and reverse transcription poly- merase chain reaction（RT-PCR） assay. Compounds ethoxysanguinarine（EOSG） and atractylodinol were found to be the hits which could significantly reduce PRRSV-associated CPE with 50% inhibited concentration（ICso） values of 7.9 and 39.4 ~tmol/L, respectively. Meanwhile, compounds ethoxysanguinarine and atractylodinol significantly de- creased mRNA expression of ORF7 gene in a dose-dependent manner. Study results suggest that compounds ethoxy- sanguinarine and atractylodinol may be useful anti-PRRSV drugs for swine industry or the hits for further lead opti- mization.