IntroductionThe normal butanol fraction of Polygonum hydropiper L. flavonoids (FNB) exhibits significant anti-inflammatory effects. This study investigated FNB's impact on inflammatory responses induced by Porcine circovirus type 2 (PCV2) in cell and mouse models.MethodsAn inflammatory model was established in RAW264.7 cells infected with varying PCV2 concentrations. And assigning both RAW264.7 cells and 108 SPF-grade KM mice to Control, PCV2, Rutin, and various dosages of FNB groups. Inflammatory factors such as Monocyte Chemoattractant Protein-1 (MCP-1), interleukin-6 (IL-6), IL-8, IL-10, Tumor Necrosis Factor-alpha (TNF-α), Reactive Oxygen Species (ROS), and Nitric Oxide (NO) were quantified using ELISA, RT-qPCR and immunohistochemistry.ResultsResults showed that a PCV2 titer of 104.5 TCID50/0.1 mL when applied to RAW264.7 cells effectively established an in vitro inflammatory model at 12 and 24 h post-infection. Following PCV2 infection, all the inflammatory factors displayed a significant increased both in culture supernatant and intracellular mRNA expression levels (p < 0.05 or p < 0.01), but these levels were reduced by FNB treatment (p < 0.05 or p < 0.01). In mouse sera post-PCV2 infection also showed elevated levels of IL-6, IL-8 IL-10, TNF-α, and MCP-1 (p < 0.05 or p < 0.01). Additionally, mRNA and protein levels for TNF-α, IL-8, IL-10, IL-6, and iNOS rose significantly in lung tissues (p < 0.01) but decreased with FNB treatment (p < 0.05 or p < 0.01).DiscussionThese findings suggest that FNB reduces inflammatory factor production and modulates the inflammatory response triggered by PCV2 infection, potentially enhancing host resistance against it.

Arthrospira platensis polysaccharide component 1 (PAP-1), a purified polysaccharide monomer isolated from Arthrospira platensis, exhibits pronounced antioxidant activity. To investigate the in vivo and in vitro regulatory effects of PAP-1 on antioxidant enzyme activities and inflammatory mediators in mice and RAW264.7 cells, the mice were administered PAP-1 by gavage, and the cells were cultured with PAP-1. Subsequently, serum, lung, spleen, and thymus tissues from mice, as well as the cultured RAW264.7 cells, were collected for analysis using RNA sequencing, commercial assay kits, immunohistochemistry, RT-qPCR, and Western blotting. The results demonstrated that PAP-1 significantly reduced the levels of oxidative stress-related indicators (NO, iNOS, MDA, MPO, and XOD), while markedly enhancing the activities of antioxidant enzymes (SOD, CAT, and GSH-Px) (p < 0.05), a trend consistently observed in both in vivo and in vitro experiments. Furthermore, PAP-1 upregulated the expression of key antioxidant genes and proteins, including HO-1, NQO1, GCLM, p62, Prdx1, and SLC7A11. Collectively, these findings indicate that PAP-1 exerts regulatory antioxidant effects in mice and RAW264.7 cells by enhancing antioxidant enzyme activity and suppressing oxidative stress responses, underscoring its potential as a natural antioxidant agent.

Flavonoid n-butanol (FNB) possess diverse pharmacological properties. This study aimed to explore the mechanism of FNB in regulating oxidative response in PCV2-infected RAW264.7 cells. PCV2-infected macrophages were treated with FNB, and oxidative stress markers, antioxidant enzyme activities, as well as related gene and protein expression were assessed to evaluate FNB's regulatory effects. Specifically, the level of Nitric Oxide (NO), Total antioxidant capacity (T-AOC), anti-hydroxyl radical capacity, anti-superoxide anion capacity, L-Glutathione (GSH) level, Super Oxide Dismutase (SOD) and Catalase (CAT) were detected. The expression of key oxidative stress-related and signaling pathway genes and proteins was determined by qPCR and western blotting, respectively. The results indicated that FNB reduced intracellular ROS, increased SOD and CAT activities, improved antioxidant capacity, upregulated the mRNA expression levels of HO-1, NQO1, Nrf2, Pi3kca, SOD, and HDAC1, downregulated AKT, Keap1, and HAT1, enhanced HDAC1 activity, and inhibited HAT activity. In conclusion, FNB protects against PCV2-induced oxidative damage by activating the PI3K/AKT pathway and inhibiting Keap1, which collectively enhance the Nrf2/HO-1 antioxidant response.

Viral infection causes oxidative stress damage to the body. Quercitrin is a flavonoid compound that exists widely in many plants and it exhibits antioxidant properties. The aim of this work was to investigate the antioxidant mechanism of quercitrin and its effect on histone acetylation changes. 3D4/2 cells were infected by PRV (Pseudorabies virus) with or without quercitrin, cell viability and antioxidant enzyme activity were tested. In addition, oxidative stress-related signaling pathways and histone acetylation changes were analyzed by western blots. The results showed that quercitrin played a protective effect on PRV infected 3D4/2 cells, the effects of quercitrin on the activity of SOD (Superoxide Dismutase), GPx (Glutathione peroxidase), CAT (Catalase) in PRV infected cell were not the same, quercitrin could increase the proteins expression levels AcH3, AcH4 and Nrf2 signaling pathway related proteins of PRV infected cells at certain concentrations. In addition, quercitrin could inhibit AKT phosphorylation in PRV infected cells and further promote the phosphorylation levels of AMPK and PPAR-γ protein expression levels. Moreover, AMPK pathway inhibitors blocked the promoting effect of quercitrin on Nrf2 and HO1 protein expression levels; PPAR-γ inhibitors blocked the promoting effect of quercitrin on Nrf2. The findings demonstrated that quercitrin could regulate histone acetylation in PRV infected 3D4/2 cells through the Nrf2 pathway and quercitrin could alleviate oxidative stress in 3D42 cells induced by PRV, which is associated with the Nrf2, AMPK, and PPAR-γ signaling pathway.

This experiment aimed to optimize the enzyme-assisted aqueous extraction process of Arthrospira platensis polysaccharides (PAP) and evaluate their in vivo antioxidant activity. The optimal extraction method for PAP was identified by comparing different techniques. Single-factor tests combined with response surface methodology were employed to optimize the enzyme-assisted aqueous extraction process, and the antioxidant activity was assessed via a mouse model. The results showed that the optimal extraction method was enzyme-assisted aqueous extraction, with the best parameters being: Enzyme hydrolysis temperature of 50 ℃, extraction time 2.5 hours, and a liquid-to-material ratio of 40 mL/g. Under these conditions, the PAP extraction yield was 17.12%, which was close to the predicted value of 17.42%. Compared with the blank group, the activities of inducible nitric oxide synthase (iNOS) and catalase (CAT) in the serum of mice infected with porcine pseudorabies virus (PRV) were significantly increased (P<0.05), and the content of malondialdehyde (MDA) was significantly reduced (P<0.05). Compared with the PRV group, serum activities of CAT and glutathione peroxidase (GSH-Px) in PRV+PAP low-dose, medium-dose, and high-dose groups were significantly increased (P<0.05), and iNOS activity was significantly decreased (P<0.05). The MDA content in the serum of the PRV + PAP high-dose group was significantly decreased (P<0.05), and the activity of superoxide dismutase (SOD) in the serum of the PRV + PAP medium dose and high-dose groups was significantly increased (P<0.05). The study shows that the PAP extracted in this experiment has strong in vivo antioxidant activity, which can provide a reference for the development and application of PAP as an antioxidant additive in animal production.

Current evidence suggests that porcine circovirus type 2 (PCV2) infection induces immunosuppression in piglets. Sophora subprostrate polysaccharide (SSP) exhibits various pharmacological activities, including immunoregulatory, anti-inflammatory, antiviral, and antioxidant properties. However, the acts of lncRNAs in regulating the therapeutic effects of SSP on PCV2-infected RAW264.7 cells remains poorly understood. This study aimed to investigate the molecular mechanisms by which lncRNAs regulate PCV2-induced immunosuppression during SSP treatment. Our findings revealed that 1699 mRNAs, 373 lncRNAs, and 129 miRNAs were differentially expressed in PCV2-infected RAW264.7 cells. Additionally, 359 mRNAs, 271 lncRNAs, and 79 miRNAs exhibited differential expression in SSP-treated PCV2-infected RAW264.7 cells. GO and KEGG analyses indicated that the candidate genes were enriched in the TNF/NF-κB signaling pathway. Furthermore, based on GO and KEGG pathway analysis, a ceRNA network involving chemokine (C-X-C motif) ligand 2 (CXCL2), miR-217-x, and MSTRG.5823.1 was constructed. We demonstrated that lncRNA MSTRG.5823.1 localized to the cytoplasm. Moreover, we found that silencing or overexpressing lncRNA MSTRG.5823.1 significantly modulated PCV2-induced immunosuppression by regulating the activation of the TNF/NF-κB signaling pathway. Specifically, lncRNA MSTRG.5823.1 overexpression increased the expression of TNF/NF-κB signaling pathway-related genes and proteins in PCV2-infected RAW264.7 cells. Conversely, silencing lncRNA MSTRG.5823.1 decreased their expression. Rescue assays further revealed that the suppressive effects of miR-217-x overexpression on TNF/NF-κB signaling pathway-related genes and proteins could be reversed by MSTRG.5823.1 overexpression. These findings highlight the critical role of lncRNA MSTRG.5823.1 in PCV2 infection progression and suggest a new strategy for the prevention and treatment of PCV2 infection.

Porcine epidemic diarrhea virus (PEDV) and rotavirus has posed a significant threat to the pig industry annually across different nations, resulting in huge economic losses. The frequent co-infection of these two viruses in clinical settings complicates the process of differential diagnoses. Rapid and accurate detection of PEDV and rotavirus is in great demand for timely diarrhea disease prevention and control. In this study, tris stabilized AuNPs were prepared and a sensitive lateral flow immunoassay (LFIA) sensor was developed for the simultaneous and rapid detection of PEDV and rotavirus on site. After the system optimization, the established LFIA can simultaneously identify PEDV and rotavirus with limits of detection (LOD) of 1.25 x 103 TCID50 mL- 1 and 3.13 x 102 pg mL-1, respectively. When applying for clinical samples, the LFIA show a concordance of 95 % and 100 % to reverse transcript polymerase chain reaction (RT-PCR) for PEDV and rotavirus respectively. Therefore, this LFIA can qualitatively detect PEDV and rotavirus in 18 min with high sensitivity and accuracy without any sophisticated equipment and operation, making it a promising candidate for the early diagnosis of PEDV or/and rotavirus diarrhea on site.

本研究旨在探索辣蓼黄酮乙酸乙酯部分(FEA)抵御猪圆环病毒2型(PCV2)感染猪肺泡巨噬细胞(3D4/2细胞)诱导的炎症反应的分子机理.试验共设置7个组,分别为空白对照组、PCV2感染组、脂多糖阳性对照组、芦丁阳性对照组和FEA药物组(25、50和100 μg/mL),每组4个重复.检测不同浓度FEA作用3D4/2细胞后的细胞活性;接种PCV2后,检测白细胞介素-6(IL-6)、干扰素-γ(IFN-γ)、白细胞介素-10(IL-10)含量及环氧合酶-1(COX-1)、环氧合酶-2(COX-2)活性;定量PCR检测COX-2、IL-6、IL-10、原癌基因(c-myc和c-fos)、氨基酸端激酶(c-jun)、p38丝裂原活化蛋白激酶(p38 MAPK)和细胞外调节蛋白激酶1/2(ERK1/2)的mRNA相对表达水平;Western-Blotting检测p38 MAPK、ERK1/2的蛋白相对表达水平.结果表明,25、50和100 μg/mL的FEA对3D4/2细胞活力无显著影响(P＞0.05).与PCV2感染组相比,25、50和100 μg/mL FEA药物组的IL-6、IL-10和IFN-γ含量显著或极显著降低(P＜0.05或P＜0.01),25和100μg/mL FEA药物组的COX-1和COX-2活性显著降低(P＜0.05),25、50和100 μg/mL FEA药物组的IL-6、IL-10、COX-2和c-f os的mRNA相 对表达水平显著或极显著降低(P＜0.05 或 P＜0.01),25 和 100 μg/mL FEA 药物组的 c-jun、c-myc、MAPK 和 ERK 的 mRNA相对表达水平显著或极显著降低(P＜0.05或P＜0.01),25、50和100μg/mL FEA药物组的p38 MAPK、ERK1/2的蛋白相对表达水平极显著降低(P＜0.01).由此可见,FEA通过减少炎症因子的产生并抑制p38 MAPK和ERK1/2蛋白磷酸化而调节PCV2诱导的3D4/2细胞的炎症反应.

信息化是当今世界发展的趋势,有效利用现代化信息技术加强学生自主学习能力的培养是专业课程教学的一个重要任务.该文首先对《兽医药理学》课程基本情况、信息化教学资源、信息化教学方法和信息化教学设计现状进行分析,然后详细分析在线教学资源、微助教、问卷星、思维导图等信息化技术在《兽医药理学》教学中的应用情况,最后展示课程组基于这些信息化教学资源和技术的教学设计.

Quercitrin is a kind of flavonoid that is found in many plants; it has good antioxidant activity, and can regulate oxidative stress induced by Pseudorabies virus (PRV)-infected cells. In this study, the secretion of reactive oxygen species (ROS) induced by PRV infection was detected by flow cytometry, and RNA expression profiles of the 3D4/2 cells were produced and analyzed by sequenced GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes); the sequencing results were verified by RT-qCR. The results showed that the secretion of ROS induced by PRV infection in 3D4/2 cells could be significantly decreased by quercitrin. The differentially expressed 1055 mRNA, 867 lncRNA, 99 miRNA, and 69 circRNA were detected between the control group and the PRV infection group. The differentially expressed 1202 mRNA, 785 lncRNA, 115 miRNA, and 79 circRNA were found between the PRV+ quercitrin group and the control group. The differentially expressed 357 mRNA, 69 lncRNA, 111 miRNA, and 81 circRNA were obtained between the PRV+ quercitrin group and the PRV group. The significantly differentially expressed mRNAs were mainly involved in cell metabolism, regulatory protein phosphorylation, protein phosphorylation, antioxidation, regulatory phosphorylation, and so on. Among them, the mRNAs related to antioxidant response and oxidative stress were thioredoxin-interacting protein (TXNIP) and nitric oxide synthase 2 (NOS2). According to the network diagram of lncRNA–miRNA–mRNA, two targeted miRNA (ssc-miR-450c-3p and novel-m0400-3p) relationships with TXNIP and NOS2 were screened. This study provides a scientific foundation for further research for the function of quercitrin in anti-virus-induced oxidative stress.

[目的]探讨猪伪狂犬病毒(Pseudorabies virus,PRV)感染对小鼠单核巨噬细胞(RAW264.7)炎症反应的影响,确定PRV的最佳感染剂量和感染时间,为建立RAW264.7细胞体外病毒感染炎症反应模型打下基础.[方法]PRV按10倍递增稀释成10-5～10-1 PRV稀释液,感染RAW264.7细胞并孵育1.5 h,弃病毒液后加入含5％胎牛血清的DMEM维持培养液继续培养,分别于继续培养2、4、8、12、24和48 h时收集细胞上清液,采用ELISA测定IL-6、IL-10、IL-1β、TNF-α、MCP-1和IFN-γ分泌水平及环氧合酶(COX-1和COX-2)活性,并以CCK-8法测定细胞活性.[结果]以PRV感染RAW264.7细胞4～48 h后均能通过PCR扩增获得PRV核酸的特异性条带,故选择4～48 h作为后续研究的PRV感染时间范围;10-2 PRV～10-1 PRV感染可显著降低RAW264.7细胞活性(P<0.05,下同),10-3 PRV组仅在培养48 h时出现下降趋势,而10-5 PRV～10-4 PRV感染对RAW264.7细胞活性无显著影响.PRV感染RAW264.7细胞后,其胞内炎症因子IL-6、IFN-γ、TNF-α、IL-1β和MCP-1的分泌水平整体上呈升高趋势,其中10-3 PRV感染RAW264.7细胞12 h能显著或极显著(P<0.01)提高IL-6、IFN-γ、TNF-α、IL-1β和MCP-1的分泌水平;10-4 PRV～10-1 PRV感染组的IL-10分泌水平均呈升高趋势,而10-5 PRV感染组在感染8和24 h时IL-10分泌水平明显低于空白对照组,至感染48 h所有病毒感染组的IL-10分泌水平均降低;10-3 PRV～10-1 PRV感染8～24 h能有效提高RAW264.7细胞的COX-2活性,但对COX-1活性的影响不明显.[结论]PRV感染能诱导RAW264.7细胞发生炎症反应,其中10-3 PRV体外感染RAW264.7细胞8～12 h是建立RAW264.7细胞炎症反应模型的最佳条件.该模型可应用于PRV感染与RAW264.7细胞炎症反应相关干预药物的研究,为进一步揭示PRV感染机理及开发抗病毒感染药物提供理论依据.

针对以MDEA为主体、MEA和PG为添加剂的2种混合胺的解吸工况,采用膜解吸法对其CO2富液进行解吸再生.在对比2种吸收液的膜解吸效果基础上,进一步考察了不同条件对CO2解吸率和解吸速率的影响.结果 表明:在相同解吸时间下,MDEA+MEA富液的解吸率比MDEA+PG富液的解吸率高;在相同吸收液质量分数下,MDEA+ PG富液的解吸效果较好;解吸温度升高和N2吹扫体积流量增大均有利于提高CO2解吸率,同时也会加速解吸进程;CO2富液体积流量增大会导致CO2解吸率下降;综合考虑,选择MDEA+MEA为吸收剂,解吸温度为50℃,CO2富液体积流量为0.89×10-3 m3/s,N2吹扫体积流量为150 mL/min.

Panax notoginseng saponins (PNS) are bioactive substances extracted from P. notoginseng that are widely used to treat cardiovascular and cerebrovascular diseases and interstitial diseases. PNS have the functions of scavenging free radicals, anti-inflammation, improving blood supply for tissue and so on.The aim of this study was to investigate the effects of PNS on the oxidative stress of immune cells induced by porcine circovirus 2 (PCV2) infection in vitro and in vivo.Using an oxidative stress model of PCV2 infection in a porcine lung cell line (3D4/2 cells) and mice, the levels of nitric oxide (NO), reactive oxygen species (ROS), total glutathione (T-GSH), reduced glutathione (GSH), and oxidized glutathione (GSSG) and the activities of xanthine oxidase (XOD), myeloperoxidase (MPO) and inducible nitric oxide synthetase (iNOS) were determined to evaluate the regulatory effects of PNS on oxidative stress.PNS treatment significantly reduced the levels of NO and ROS, the content of GSSG and the activities of XOD, MPO, and iNOS (p < 0.05), while significantly increasing GSH and the ratio of GSH/GSSG in infected 3D4/2 cells (p < 0.05).Similarly, in the in vivo study, PNS treatment significantly decreased the level of ROS in spleen lymphocytes of infected mice (p < 0.05), increased the levels of GSH and T-GSH (p < 0.05), significantly decreased the GSSG level (p < 0.05), and decreased the activities of XOD, MPO, and iNOS.PNS could regulate the oxidative stress of immune cells induced by PCV2 infection in vitro and in vivo.

Background: Panax notoginseng saponins (PNS) are bioactive substances extracted from P. noloqinseng that are widely used to treat cardiovascular and cerebrovascular diseases and interstitial diseases. PNS have the functions of scavenging free radicals, anti-inflammation, improving blood supply for tissue and so on. Objectives: The aim of this study was to investigate the effects of PNS on the oxidative stress of immune cells induced by porcine circovirus 2 (PCV2) infection in vitro and in vivo. Methods: Using an oxidative stress model of PCV2 infection in a porcine lung cell line (3D4/2 cells) and mice, the levels of nitric oxide (NO), reactive oxygen species (ROS), total glutathione (T-GSH), reduced glutathione (GSH), and oxidized glutathione (GSSG) and the activities of xanthine oxidase (XOD), myeloperoxidase (MPO) and inducible nitric oxide synthetase (iNOS) were determined to evaluate the regulatory effects of PNS on oxidative stress. Results: PNS treatment significantly reduced the levels of NO and ROS, the content of GSSG and the activities of XOD, MPO, and iNOS (p < 0.05), while significantly increasing GSH and the ratio of GSH/GSSG in infected 3D4/2 cells (p < 0.05).Similarly, in the in vivo study, PNS treatment significantly decreased the level of ROS in spleen lymphocytes of infected mice (p < 0.05), increased the levels of GSH and T-GSH (p < 0.05), significantly decreased the GSSG level (p < 0.05), and decreased the activities of XOD, MPO, and iNOS. Conclusions: PNS could regulate the oxidative stress of immune cells induced by PCV2 infection in vitro and in vivo.

钙法是一种利用Ca(OH)2夺取MDEA/PG富液中CO2并以CaCO3的形式解吸富液、固定CO2的一种低能耗、低成本的一体化化学再生方法.针对其工艺过程,通过单因素试验分析并考察投加方式、投加量、CO2负荷、解吸温度、搅拌速率对CO2解吸率的影响.结果 表明,解吸效果最佳工况为CO2负荷为0.8 mol/L、0.5 mol Ca(OH)2+0.5 mol Ca(OH)2、CO2与Ca(OH)2摩尔比为1∶1、反应时间为15 min、解吸温度为20℃及搅拌速率为800 r/min.

CO2化学吸收法分离纯度高,技术成熟,但能耗过高及成本是困扰该技术发展的瓶颈.在常压条件下对利用Ca(OH)2直接矿物碳酸化固定MDEA/PZ混合吸收富液中CO2进行了一系列实验研究,考察了吸收液负荷、Ca(OH)2投加量、pH、温度及搅拌速率等因素对解吸率的影响,并利用动态吸收-解吸循环实验研究了其CO2吸收性能和循环使用稳定性,最后对碳酸化反应产物进行了XRD、TEM分析.结果表明,在常压条件下,Ca(OH)2可以通过液相直接矿物碳酸化对CO2进行直接固定,并实现吸收富液的再生;随着负荷的升高及Ca(OH)2投加量、pH、搅拌速率的增大,解吸率随之增加;随着溶液温度升高,解吸率下降;经过5次动态吸收-解吸循环实验后CO2吸收量可以达到并保持在0.57 mol· L-1,显示出了良好的循环稳定性.

Aiming at the shortage of CO2 desorption process, a new desorption method, fixing CO2 by adding calcium hydroxide CO2-loaded amine solution (MDEA + MEA), was proposed in this paper. The emitted CO2 was converted into CO32- using amine solution (MDEA + MEA), and then made into carbonate, a product of mineralization, by combining the Ca(OH)(2) with Ca2+ and the OH- released by Ca(OH)(2) which can neutralize the protonated amines and convert them into fresh amines at 20 degrees C and ambient pressure. And the associated desorption mechanisms by adding calcium hydroxide into CO2-loaded amine solution (MDEA + MEA) was investigated. The effects of CO2 loading, C/Ca molar ratio, reacting time, temperature and stirring rate on CO2 desorption rate were systematically investigated in desorption and mineralisation process. The results indicated that changing the C/Ca molar ratio, CO2 loading, reacting time, temperature and stirring rate have an effectively influence the desorption efficiency. The performance stability of the amine solution (MDEA + MEA) was verified in multicycle-cycle experiments. In addition, CO2 capture efficiency of different amine solutions was also studied. The results indicated that 1 mol/L MEA + 1 mol/L MDEA as high as 61.03% was achieved which is 19.28% higher than that of its counterpart (0.2 mol/L MEA + 1 mol/L MDEA). Multiple-cycle experiments showed that CO2-loaded amine solution (MDEA + MEA) achieved stable cyclic loading (0.537molCO(2)/L) and regeneration efficiency (72.47%). This was further confirmed the coordinated mechanism of carbonation reaction between CO2 and Ca(OH) 2 using mineral composition analysis (XRD), thermogravimetric analysis (TGA) and transmission electron microscope (TEM). It is verified that calcium hydroxide can reduce and reuse emitted CO2, thereby making CO2 a potential future resource.

[目的]建立苦玄参提取物中苦玄参苷ⅠA的鉴别和含量测定方法.[方法]采用薄层色谱法对苦玄参苷进行定性鉴别;采用高效液相色谱法测定提取物中苦玄参苷ⅠA的含量,色谱条件为:Waters Symmetry C18(4.6×250 mm,5μm)色谱柱,流动相为乙腈—水(35:65),流速1.0 mL/min,检测波长264 nm,柱温35℃,进样量20μL.[结果]苦玄参苷ⅠA的薄层色谱鉴别方法专属性强;苦玄参苷ⅠA在20.06~104.10μg/mL的质量浓度范围内线性关系良好(R2=0.9992),平均加样回收率为99.90%,RSD=0.53%.[结论]建立的方法专属性强,定量准确性高,适用于苦玄参提取物的质量控制.

为了解广西地区牛呼吸道疾病综合征(bovine respiratory disease complex,BRDC)的病原情况,本研究通过RT-PCR/PCR方法和细菌分离鉴定方法对2016-2017年送检的117份患有呼吸道疾病的病料进行病原诊断,并对主要分离菌进行药物敏感性试验.结果 显示,RT-PCR/PCR方法检测的肺炎克雷伯氏菌、牛支原体、化脓隐秘杆菌、多杀性巴氏杆菌、牛传染性鼻气管炎病毒(IBRV)、溶血性曼氏杆菌的检出率分别为41.0％(48/117)、28.2％(33/117)、20.5％(24/117)、15.4％(18/117)、12.8％(15/117)、5.1％(6/117),而细菌分离鉴定方法检测的肺炎克雷伯氏菌、大肠杆菌、牛支原体、化脓隐秘杆菌、多杀性巴氏杆菌、溶血性曼氏杆菌的检出率分别为41.0％(48/117)、33.3％(39/117)、17.1％(20/117)、7.7％(9/117)、2.6％(3/117)、2.6％(3/117),牛副流感病毒3型、牛呼吸道合胞体病毒和牛病毒性腹泻病毒未检出,且PCR方法更敏感.药敏试验结果显示,20株牛支原体对β-内酰胺类、磺胺类、多肽类药物的耐药率为90.0％～100.0％,对喹诺酮类、庆大霉素、阿米卡星和卡那霉素敏感(耐药率为在10.0％～25.0％);30株大肠杆菌和30株肺炎克雷伯氏菌除了对头孢噻肟、头孢曲松和头孢他啶敏感外(耐药率分别为13.3％～20.0％、10.0％～30.0％),对其他15种药物均具有耐药性(耐药率分别为50.0％～100.0％、40.0％～100.0％).综上所述,广西地区牛呼吸道疾病主要以牛支原体、大肠杆菌和肺炎克雷伯氏菌引发的混合感染为主,且分离菌均已出现不同程度的耐药性.