内毒素诱导的红细胞过氧化损伤及山莨菪碱的保护效应

通过给山羊静脉注射大肠杆菌内毒素复制的休克模型，研究了内毒素诱导的红细胞脂质过氧化损伤，并观察了山莨菪碱的相关保护效应。将３０头山羊随机分成３组，第Ⅰ组（ｎ＝６）静注生理盐水作为正常对照，第Ⅱ组（ｎ＝１２）静注大肠杆菌（Ｏ１１１Ｂ４）内毒素２次（间隔２４ｈ），第Ⅲ组（ｎ＝１２）处理同第Ⅱ组，仅处理前１０ｍｉｎ静注山莨菪碱。分别于处理后１、３、５、７、９、１２ｈ采血，制备样本供测定。结果显示，山羊注射内毒素１ｈ后，红细胞脂质过氧化物含量明显增加（Ｐ＜０．０１），红细胞膜还原型谷胱甘肽（ＧＳＨ）含量显著下降（Ｐ＜０．０１），并伴有红细胞ＳＯＤ、ＧＳＨ－Ｐｘ、ＧＲ活性降低（Ｐ＜０．０１，Ｐ＜０．０５）；而注射内毒素前给与山莨菪碱的山羊，其上述各项指标的变化均较小。以上结果表明，内毒素可使红细胞脂质过氧化作用增强，而山莨菪碱能拮抗红细胞的这种过氧化损伤，对细胞有一定的保护作用。

Antiviral Activity of the Effective Monomers from Folium Isatidis Against Influenza Virus in Vivo

In order to evaluate the anti-influenza virus activity of the effective monomer from Folium Isatidis (FI) in vivo,we established mice model with viral pneumonia and divided them into 3 different dose groups,then observed their lung indexes,pulmonary pathological changes,pulmonary virus hemagglitination titers,living time and death rates.The results showed that the monomer could reduce the pulmonary index from 2.64 to 1.93,1.63 and 1.40 (P<0.01) and decrease the hemagglitination titer from 1.15 to 0.84,0.70 and 0.59 (P<0.01).In addition,different groups of FI could significantly lessen the mortality rate from 100% to 30%,25% and 15%,and prolong the living time from 5.1d to 6.5d,8.4d and 8.9d respectively(P<0.01).The high dose (75 mg/kg/d) has the similar effect with 100 mg/kg/d dose of virazole(P>0.05),and more effective than 200 mg/kg/d dose of antiviral liquor (P<0.05).

Prevalence of porcine endogenous retrovirus in Chinese pig breeds and in patients treated with a porcine liver cell-based bioreactor

AIM： To determine the prevalence of porcine endogenous retrovirus （PERV） in various pig breeds raised in China including Chinese experimental mini-pigs by PERV-reverse transcriptase （PERV-RT enzyme）. Moreover, the potential for infection of PERV was investigated in patients treated with a bioreactor based on porcine liver cells （n = 3）. METHODS： Pig serum, liver and muscle cell-free supernatants were collected from various Chinese pig breeds. Porcine hepatocytes were isolated with a two-step perfusion method. Three patients with acute or chronic liver failure were treated with a bioartificial liver support system （BALSS） for 8-12 h and serum samples were collected from the patients before, immediately after and 30 d after treatment. RESULTS： The activities of PERV-RT enzyme in pig liver and muscle cell-free supernatants were higher than in normal human controls. PERV-TR enzyme activity did not increase in patients before and after 1 mo of treatment. PERV-RT activities were not significantly different when compared with pre-treatment group （1.544±0.155576）, the post-treatment groups （1.501±0.053507, 1.461±0.033808 and 1.6006667±0.01963 for 0, 14 and 30 d post-treatment, respectively, P〉0.05）, and normal control group （1.440±1.0641, P〉0.05）. RT enzyme activity in Chinese experimental mini-pigs was higher than in normal human control group （1.440±1.0641 U/mL, P〈0.05）, and not significantly different （P〉0.05） when compared with the pig breeds except in the muscle supernatants. All the samples including muscle and liver cell supernatants from the Chinese mini-experimental pigs and the four domestic Chinese pig breeds contained PERVs. CONCLUSION： These results suggest that the risk of PERV infection through BALSS containing porcine liver cells without immunosuppressants may be quite low. Although there were PERVs in Chinese experimental mini-pigs and porcine liver cell culture suspensions, we did not find any evidence of persistent PERV infection in patients treated with this porcine hepatocyte-based bioartificial liver.

Use of flow cytometry to investigate the cytokine response pattern in infants with respiratory syncytial virus infection and bronchiolitis

Objective: To investigate the cytokine response pattern (IL 4/IFN γ ) in infants with RSV infections and bronchiolitis during the acute phase. Methods: Four color flow cytometry was used to measure intracellular IL 4 and IFN γ expressions in peripheral blood CD3+ and CD8+ lymphocytes from RSV infected and bronchiolitis infants. Serum IL 4 and IFN γ levels were also determined. Results: RSV infected and bronchiolitis infants showed no statistical differences from not RSV infected or pneumonia infants and control in the frequency of IL 4 and IFN γ expressions in CD3+CD8 lymphocytes, showed no obvious Th1/Th2 imbalance, while IFN γ was expressed much more frequently in CD3+CD8+ lymphocytes. Systematically, RSV infected and bronchiolitis infants showed much lower levels of serum IL 4 and IL 4/IFN γ ratios and much higher serum IFN γ levels than control. However, there were no statistical differences in the above three indices between RSV infected and not RSV infected infants or between bronchiolitis and pneumonia infants, except that bronchiolitis infants had a higher level of serum IFN γ than pneumonia infants statistically. Conclusions: There is no type 2 cytokine response predominance in the acute phase of RSV infection and bronchiolitis. IL 4 production is suppressed and IFN γ production upregulated, the latter being most prominent in bronchiolitis infants.

Extracellular domain of kinase domain region mediated by adeno-associated virus inhibits growth and angiogenesis of bladder cancer in Balb-c mice

OBJECTIVE: To verify whether the extracellular domain of kinase domain region (KDR) has anti-angiogenesis activity in vivo. METHODS: cDNA was cloned into adeno-associated virus (AAV) vector pSNAV and transfected to baby hamster kidney (BHK) cells. Recombinant AAV was obtained from the cell culture supernatant after adding helper virus. Recombinant AAV-infected human bladder cancer EJ cell line (EJ cells) were injected subcutaneously into Balb-c nude mice. Tumor specimens were removed from the mice, paraffin-embedded and sliced, then stained by immunohistochemistry. Microvessel density (MVD) was determined under a microscope. RESULTS: The tumor volume developed by EJ cells transfected with the extracellular domain of KDR was significantly smaller (1.70 +/- 0.18 cm(3)) compared with that in the control (5.62 +/- 0.67 cm(3)) (P

Analysis of an improved workflow of endoscope reprocessing for bedside endoscopic diagnosis and treatment on COVID-19 patients

Severe cases infected with the coronavirus disease 2019(COVID-19),named by the World Health Organization(WHO)on Feb.11,2020,tend to present a hypercatabolic state because of severe systemic consumption,and are susceptible to stress ulcers and even life-threatening gastrointestinal bleeding.Endoscopic diagnosis and treatment constitute an irreplaceable part in the handling of severe COVID-19 cases.Endoscopes,as reusable precision instruments with complicated structures,require more techniques than other medical devices in cleaning,disinfection,sterilization,and other reprocessing procedures.From 2016 to 2019,health care-acquired infection caused by improper endoscope reprocessing has always been among the top 5 on the list of top 10 health technology hazards issued by the Emergency Care Research Institute.Considering the highly infective nature of COVID-19 and the potential aerosol contamination therefrom,it is of pivotal significance to ensure that endoscopes are strictly reprocessed between uses.In accordance with the national standard"Regulation for Cleaning and Disinfection Technique of Flexible Endoscope(WS507-2016),"we improved the workflow of endoscope reprocessing including the selection of chemicals in an effort to ensure quality control throughout the clinical management towards COVID-19 patients.Based on the experience we attained from the 12 severe COVID-19 cases in our hospital who underwent endoscopy 23 times in total,the article provides an improved version of endoscopic reprocessing guidelines for bedside endoscopic diagnosis and treatment on COVID-19 patients for reference.

A novel endogenous badnavirus exists in Alhagi sparsifolia

We report the recovery of a 7068-nt viral sequence from the ＂viral fossils＂ embedded in the genome of Alhagi sparsifolia, a typical desert plant. Although the full viral genome remains to be completed, the putative genome structure, the deduced amino acids and phylogenetic analysis unambiguously demonstrate that this viral sequence represents a novel species of the genus Badnavirus. The putative virus is tentatively termed Alhagi bacilliform virus （ABV）. Southern blotting and inverse polymerase chain reaction （PCR） data indicate that the ABV-related sequence is integrated into the A. sparsifolia genome, and probably does not give rise to functional episomal virus. Molecular evidence that the ABV sequence exists widely in A. sparsifolia is also presented. To our knowledge, this is the first endogenous badnavirus identified from plants in the Gobi desert, and may provide new clues on the evolution, geo- graphical distribution as well as the host range of the badnaviruses.

A novel strategy to inhibit the reproduction and translation of hepatitis C virus

Hepatitis C virus (HCV), a positive single-stranded RNA virus, is a major cause of liver disease in humans. Herein we report a novel strategy to inhibit the reproduction and translation of HCV using a short RNA, named an Additional RNA, to activate the endonuclease activity of Argonaute 2 (Ago2). In the presence of the Additional RNA, the HCV genome RNA has the requisite 12 nucleotides of base-pairing with microRNA-122. This activates the endonuclease activity of Ago2, resulting in cleavage and release of the HCV genome RNA from Ago2 and microRNA-122. The free HCV genome RNA would be susceptible to intracellular degradation, effectively inhibiting its reproduction and translation. This study presents a new method to inhibit HCV that may hold great potential for HCV treatment in the future.