The tumor provides a favorable microenvironment for the growth of anaerobes and facultative anaerobes, such as Salmonella. Melittin (MEL) is a major component of bee venom that has a distinct inhibitory effect on tumor cell metastasis and invasion, but its clinical application is limited owing to non-specific cytotoxicity. Arg-Gly-Asp (RGD) is a potent competitive antagonist of extracellular matrix binding to αvβ3, and is often used as a tumor-targeting marker. Here, we engineered Salmonella typhimurium to selectively express and release RGD-MEL. The engineered bacteria were intratumourally injected into mice bearing B16 melanoma xenografts. We observed that RGD-mediated expression and release of MEL by S. Typhimurium promoted apoptosis while inhibiting B16 cell proliferation, migration, chemotaxis, and invasion. LH430/pRGD-MEL also had a prominent inhibitory effect on solid tumors. By leveraging the combined mechanisms of RGD and S. Typhimurium, LH430/pRGD-MEL demonstrates enhanced accumulation and expression within tumor tissues. Furthermore, no signs of tumor cell metastasis or noticeable lesions were observed in the liver and lungs. Notably, the mice treated with LH430/pRGD-MEL exhibited significantly prolonged survival. RNA sequencing analysis revealed that engineered S. Typhimurium primarily disrupted the immune barrier within tumor tissue and inhibited tumor growth by upregulating apoptosis and phagocytosis-related pathways. These results indicate that LH430/pRGD-MEL demonstrates strong tumor-targeting capacity, minimizes host toxicity, and exhibits significant tumor-suppressive effects by promoting tumor cell apoptosis, highlighting the translational potential of microbial-mediated precision oncology strategies.

Porcine Rotavirus (PoRV) is a significant pathogen affecting swine-rearing regions globally, presenting a substantial threat to the economic development of the livestock sector. At present, no specific pharmaceuticals are available for this disease, and treatment options remain exceedingly limited. This study seeks to design a multi-epitope peptide vaccine for PoRV employing bioinformatics approaches to robustly activate T-cell and B-cell immune responses. Two antigenic proteins, VP7 and VP8*, were selected from PoRV, and potential immunogenic T-cell and B-cell epitopes were predicted using immunoinformatic tools. These epitopes were further screened according to non-toxicity, antigenicity, non-allergenicity, and immunogenicity criteria. The selected epitopes were linked with linkers to form a novel multi-epitope vaccine construct, with the PADRE sequence (AKFVAAWTLKAAA) and RS09 peptide attached at the N-terminus of the designed peptide chain to enhance the vaccine’s antigenicity. Protein-protein docking of the vaccine constructs with toll-like receptors (TLR3 and TLR4) was conducted using computational methods, with the lowest energy docking results selected as the optimal predictive model. Subsequently, molecular dynamics (MD) simulation methods were employed to assess the stability of the protein vaccine constructs and TLR3 and TLR4 receptors. The results indicated that the vaccine-TLR3 and vaccine-TLR4 docking models remained stable throughout the simulation period. Additionally, the C-IMMSIM tool was utilized to determine the immunogenic triggering capability of the vaccine protein, demonstrating that the constructed vaccine protein could induce both cell-mediated and humoral immune responses, thereby playing a role in eliciting host immune responses. In conclusion, this study successfully constructed a multi-epitope vaccine against PoRV and validated the stability and efficacy of the vaccine through computational analysis. However, as the study is purely computational, experimental evaluation is required to validate the safety and immunogenicity of the newly constructed vaccine protein.

HCC is the most common fatal malignancy. Although surgical resection is the primary treatment strategy, most patients are not eligible for resection due to tumor heterogeneity, underlying liver disease, or comorbidities. Therefore, this study explores the possibility of multi-molecular targeted drug delivery in treating HCC. In this study, we constructed the recombinant adenovirus co-expressing apoptin and melittin (MEL) genes. The inhibitory effect of the recombinant adenovirus on hepatocellular carcinoma cells was detected through experiments on cell apoptosis, migration, invasion, and other factors. The tumor inhibitory effect in vivo was assessed using subcutaneous HCC mice. Results showed that recombinant adenovirus co-expressing anti-tumor genes TAT and apoptin, RGD and MEL can significantly inhibit the proliferation, migration, and invasion of HCC cells by inducing an increase in reactive oxygen species (ROS) levels, upregulation of apoptotic proteins such as Bax, cleaved caspase-3, and cleaved caspase-9, and downregulation of the anti-apoptotic protein Bcl-2. In subcutaneous HCC mice, recombinant adenovirus induced significant apoptosis in tumor, and inhibited tumor growth. In conclusion, recombinant adenovirus co-expressing apoptin and MEL can inhibit the growth and proliferation of tumor cells both in vivo and in vitro.

为了表达一种高效低毒的广谱抑菌蛋白,试验通过T2A连接肽连接蜂毒肽(MEL)与斜带石斑鱼c型溶菌酶(Ec-cLYZ)基因,并克隆至pPICZαA质粒上构建重组表达质粒;将鉴定正确的重组表达质粒用限制性内切酶Sac Ⅰ线性化后电转化至毕赤酵母表达菌株GS115感受态细胞中,构建毕赤酵母表达菌株;利用0.5％甲醇诱导表达,收集上清液进行冻干浓缩并纯化,采用Western-blot法检测重组蛋白的表达情况,BCA蛋白浓度测定试剂盒测定重组蛋白浓度,试管二倍稀释法分别检测不同浓度重组蛋白对兔红细胞的溶血活性,牛津杯法评价重组蛋白的抑菌效果.结果表明:成功构建出重组表达质粒pPICZαA-Ec-cLYZ-MEL、pPICZαA-Ec-cLYZ和pPICZαA-MEL及毕赤酵母表达菌株GS115/pPICZαA-Ec-cLYZ-MEL、GS1 15/pPICZαA-Ec-cLYZ 和 GS115/pPICZαA-MEL;经甲醇诱导,GS115/pPICZαA-Ec-cLYZ-MEL表达出分子质量为 16.5,3.4 ku 的重组蛋白,GS115/pPICZαA-Ec-cLYZ表达出分子质量为16.5 ku的重组蛋白,GS115/pPICZαA-MEL表达出分子质量为3.4 ku的重组蛋白;上清液中重组蛋白Ec-cLYZ-MEL、Ec-cLYZ、MEL的浓度分别为35.49,28.73,27.31 mg/L;重组蛋白Ec-cLYZ-MEL、Ec-cLYZ、MEL在浓度为150 mg/L时对兔红细胞的溶血率分别为2.3％、2.9％、79.0％;停乳链球菌对重组蛋白Ec-cLYZ-MEL高度敏感,表皮葡萄球菌对重组蛋白Ec-cLYZ-MEL中度敏感,金黄色葡萄球菌和大肠杆菌对重组蛋白Ec-cLYZ-MEL低度敏感,且重组蛋白Ec-cLYZ-MEL对测试菌株的抑菌效果优于重组蛋白Ec-cLYZ和MEL.说明重组蛋白Ec-cLYZ-MEL 对红细胞无溶血活性且具有良好的抑菌活性.

旨在利用毕赤酵母表达系统表达出具有良好抑菌效果的重组抗菌肽.选定昆虫死亡素thanatin基因和斑点叉尾鮰β-防御素基因(命名为defbl),按毕赤酵母偏好性密码子优化后,将用T2A剪切肽连接的共表达基因(命名为TD)及各单基因分别构建至pMD19-T载体上,经EcoR Ⅰ、SalⅠ双酶切后亚克隆至表达载体pPICZaA上,经Sac Ⅰ线性化后电转化至毕赤酵母GS115感受态细胞中,通过Zeocin抗性及PCR筛选出阳性菌株,利用1％甲醇进行诱导表达,72 h后收集培养基上清液,冻干浓缩并纯化后,进行Western blot检测及体外抑菌试验、溶血性试验.结果显示,成功构建重组毕赤酵母工程菌株GS115-pPICZαA-thanatin、GS115-pPICZαA-defbl和GS115-pPICZαA-TD,通过甲醇诱导成功获得重组蛋白,纯化后Westernblot检测结果显示,thanatin组和defbl组分别在2.3kDa和7.8kDa处出现特异性条带,TD组同时出现上述2条带,蛋白大小均与预期相符;3个重组蛋白浓度分别为600、300和700 μg/mL;体外抑菌试验及溶血性试验结果显示,各重组蛋白均具有良好的抑菌作用,TD重组蛋白抑菌效果最佳,且所获蛋白均具有较低溶血性.研究表明,利用酵母表达系统成功获得具有良好抑菌效果且溶血性低的重组抗菌肽,相较之下,TD组抗菌肽抑菌效果最佳.本研究结果为后续进一步探索上述抗菌肽的功能及临床应用奠定基础.

Abstract Metal-Organic Frameworks (MOFs) are a kind of porous crystalline compounds, which are self-assembled by metal clusters and organic ligands through coordination bonds. UiO66 is a kind of MOF crystal materials with a porous octahedral structure, which is coordinated by zirconium ion and terephthalic acid (H2BDC). In this paper, UiO66-NH2 and UiO66-(COOH)2 were prepared, and UiO66-NH2 was modified by Post-Synthetic Modification (PSM) to obtain UiO66-NH2-COOH material. The prepared samples and intermediate products were characterized by infrared spectrum (IR). UiO66-NH2-COOH and UiO66-(COOH)2 materials were loaded with horseradish peroxidase (HRP), which catalyzed the reaction between H2O2 and 3, 3', 5, 5'-tetramethylbenzidine (TMB). Via the results of UV-vis spectrophotometry measurement, it was found that UiO66-(COOH)2 loaded with HRP had better catalytic effects than only HRP. In order to verify the influence of carboxyl groups on UiO66-NH2-COOH and UiO66-(COOH)2 materials, the adsorption of rhodamine B (RhB) was studied in this paper. The results of fluorescence spectrophotometer showed that UiO66-NH2-COOH material had better adsorption effect on RhB than UiO66-(COOH)2 material, which may be attributed to the flexibility of UiO66-NH2-COOH material after PSM. UiO66-NH2-COOH and UiO66-(COOH)2 materials were characterized by X-ray powder diffraction (XRD) before and after adsorption of RhB. The XRD pattern of UiO66-(COOH)2 material has no obvious characteristic peak, which indicates that it belongs to nanoparticle polymer. The results are consistent with the UV-visible results, and the nanoparticle polymer has better catalytic effects.

立德树人是高校课程思政的根本任务和育人核心.农科课程思政的重要任务是培养服务乡村振兴,知农、爱农的社会主义现代化农业的建设者.本文通过探索《兽医流行病学》课程思政建设,分析该课程思政教育的现状和目的,结合兽医流行病学课程各部分教学内容,深入发掘思政教育元素,并提供课程思政实施的途径,旨在促进专业知识和思政教育的有机融合,为动物医学专业课程思政提供参考.

旨在构建牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)多表位基因与BVDV结构蛋白E0、E2基因的表达载体并检测其免疫效果.从NCBI上获得BVDV的4种具有免疫原性的结构蛋白C、E0、E2、NS3基因序列,利用生物学方法预测其B、T细胞表位;将获得的序列进行连接,重组获得新肽段(命名为AKK),通过生物学在线软件分析AKK序列的二级结构、亲水性、抗原性、三级结构;PCR分别扩增上述基因序列,构建重组表达载体GV658-AKK-E0-E2、GV658-AKK、GV658-E0、GV658-E2,并将上述构建成功的无内毒素重组质粒转染至MDBK细胞,通过蛋白免疫印迹.经PCR扩增获得2 910、1 170、951和729 bp大小的目的条带,与预计相符;经蛋白免疫印迹验证,在34和68 kDa处有AKK蛋白及E0-E2蛋白的融合表达;经流式细胞术验证显示,在CD3+、CD4+细胞占比上,共表达组极显著高于PBS组,显著高于E0组,与ELISA检测IgG抗体水平结果一致.研究表明,试验成功设计了 BVDV多表位序列AKK,并成功构建真核表达载体,AKK、E0、E2蛋白高效表达,共表达组能更好地刺激机体的体液免疫和细胞免疫应答.

为了开发基于乳酸乳球菌载体表达的新型沙门氏菌口服疫苗,试验按照乳酸菌偏好优化密码子,将合成的截短的聚-γ-谷氨酸合成酶A(PgsA')和截短的沙门氏菌鞭毛融合基因(Salmonella FliC)克隆到载体pUC57中,通过PCR和双酶切鉴定正确性;通过双酶切和T4连接插入目的 基因到乳酸乳球菌表达载体pNZ8048中,构建重组质粒pNZ8048-PgsA'-FliC,通过PCR和双酶切鉴定正确性;提取质粒后将重组质粒利用电穿孔法转入乳酸乳球菌(Lactococcus lactis,L.lactis)NZ9000中,挑取阳性克隆,扩增培养后提取质粒,通过PCR和双酶切鉴定正确性;通过Western-blot检测外源基因在重组菌中的表达情况;对Balb/c小鼠口服免疫重组乳酸乳球菌NZ9000/pNZ8048-PgsA'-FliC,以NZ9000/pNZ8048和PBS为对照,通过ELISA测定小肠黏液中特异性sIgA抗体表达水平.结果 表明:成功构建了重组质粒pNZ8048-PgsA'-FliC与重组乳酸乳球菌NZ9000/pNZ8048-PgsA'-FliC,并成功表达PgsA'-FliC蛋白,分子质量约为45 ku,重组蛋白在乳酸乳球菌细胞壁、破碎沉淀和破碎上清液均有表达.首免后10,20,30天,灌服乳酸乳球菌NZ9000/pNZ8048小鼠的FliC特异性sIgA水平均与灌服PBS的小鼠差异不显著(P＞0.05).首免后10,30天,灌服重组乳酸乳球菌NZ9000/pNZ8048-PgsA'-FliC小鼠的FliC特异性sIgA水平显著高于灌服PBS的小鼠(P＜0.05);首免后20天,极显著高于灌服PBS的小鼠(P＜0.01).说明构建的重组乳酸乳球菌疫苗能引起动物产生特异性黏膜免疫.

Infectious bursal disease virus (IBDV) infection causes pathogenicity and mortality in chickens, leading to huge economic losses in the poultry industry worldwide. Studies of host-virus interaction can help us to better understand the viral pathogenicity. As a highly conservative host factor, heat shock protein 70 (Hsp70) is observed to be involved in numerous viral infections. However, there is little information about the role of chicken Hsp70 (cHsp70) in IBDV infection. In the present study, the increased expression of cHsp70 was observed during IBDV-infected DF-1 cells. Further studies revealed that Hsp70 had similar locations with the viral double-stranded RNA (dsRNA), and the result of pull-down assay showed the direct interaction between cHsp70 with dsRNA, viral proteins (vp)2 and 3, indicating that maybe cHsp70 participates in the formation of the replication and transcription complex. Furthermore, overexpression of cHsp70 promoted IBDV production and knockdown of cHsp70 using small interfering RNAs (siRNA) and reducedviral production, implying the necessity of cHsp70 in IBDV infection. These results reveal that cHsp70 is essential for IBDV infection in DF-1 cells, suggesting that targeting cHsp70 may be applied as an antiviral strategy.

为了评价猪传染性胸膜肺炎与猪肺疫二联亚单位疫苗(由多杀性巴氏杆菌外膜蛋白H (OmpH)质粒导入胸膜肺炎放线杆菌(APP)菌影制备)的免疫效果,于某规模化猪场选取30头无上述病原菌和抗体的4周龄(w)仔猪,随机分为安全评估组和试验组进行免疫,试验组包括APP组、OmpH组、APP+OmpH联苗组,分别于4、6w肌肉注射2 mL/头相应疫苗,采取4、6、9 w外周血,用流式细胞术、ELISA、血常规、血生化试验分析疫苗免疫后,相关免疫因子、免疫细胞及免疫球蛋白的变化.结果显示:APP+OmpH组外周血中CD3+、CD8+细胞增加数量比APP,OmpH组显著增多(P＜0.05);血清抗体结果显示,APP+OmpH组结果优于APP和OmpH组;APP+OmpH组的外周血白细胞数、淋巴细胞数、中性粒细胞数、单核细胞数在二免后增多,白蛋白、球蛋白亦明显增加,且APP+OmpH组增加数量多于APP和OmpH组.结论:APP+OmpH组能更好地刺激机体细胞免疫和体液免疫反应,进而发挥免疫保护效果.

旨在提高烯丙孕素原药在水中的溶解度，提高烯丙孕素原药的生物利用度，使用磺丁基-β-环糊精对烯丙孕素原药进行包合。本试验使用冷冻干燥法来制备烯丙孕素-磺丁基-β-环糊精包合物，以此来解决烯丙孕素在临床使用中因其水不溶性而受到限制及其使用后生物利用度低的问题，进而拓宽烯丙孕素的药用途径。通过傅里叶变换红外光谱法、热重分析法和显微镜成像法对所制得的烯丙孕素包合物进行表征，并用溶解度法对包合物进行溶解度测定。以包合物的收率和包合率为评价指标，筛选最优的包合物制备条件。结果显示：经筛选，包合物的最佳制备条件：在55℃，ALT与SBE-β-CD的投料摩尔比为1：6，包合时间为5 h，溶液pH为8，溶剂量为15 mL（当以ALT投药量为0.1 g时计）；以最优制备条件制备所得的包合物中ALT的平均包合率为（90.90±1.80）%（n=3），平均载药量为（4.30±2.30）%（n=3），包合物的收率为（93.19±1.67）%。经傅里叶变换红外光谱法、热重分析法和显微镜成像法对所制得的包合物进行表征，可证实成功制得包合物。溶解度法试验结果表明，形成包合物后，其溶解度较烯丙孕素原药提高了988.86倍，且该包合物稳定性好，可满足不同剂型的要求。磺丁基-β-环糊精对烯丙孕素原药具有较好的增溶作用，达到了增加药物溶解度的目的，且该制备方法简单，条件温和，易于产业化生产，有利于烯丙孕素的进一步开发利用。

为构建一种安全有效的传染性胸膜肺炎放线杆菌(APP)与多杀性巴氏杆菌二联亚单位疫苗,通过在线生物软件对APP的外毒素Apx Ⅳ与Pm的外膜蛋白H(OmpH)基因进行T细胞和B细胞表位筛选;将筛选的优势抗原表位序列通过连接肽连接后,构建新肽段(命名为New),并利用在线生物信息软件对其进行分析;分别将Apx Ⅳ、OmpH和New基因序列通过同源重组的方法构建至真核表达载体GV658,通过双酶切验证目的 基因的大小;将新构建的3种重组质粒转染HEK293细胞,CCK-8试验评估其对细胞的安全性;RT-PCR和Western blot验证外源基因蛋白的转录和表达情况;免疫荧光(IFA)验证重组质粒中外源基因蛋白在细胞中的免疫定位.结果 显示,New肽段具有较好的免疫源性,所构建的重组质粒GV658-Apx Ⅳ、GV658-OmpH和GV658-New双酶切结果与目的 基因大小相符,可转染HEK293细胞并成功表达,且对HEK293细胞无明显损伤作用.本研究所构建的3种质粒等比混合,可用于制备APP与Pm二联亚单位疫苗.

Malignant melanoma, an increasingly common form of skin cancer, poses a significant threat to public health, especially when the disease progresses past skin lesions to the stage of advanced metastasis. In this work, a new anti-tumor peptide, temporin La (T-La), was selected from a cDNA library generated from bullfrog skin. Two new derivative antitumor peptides, T-La (S) and T-La (FS), were designed by bioinformatics analysis and coupled with the RGD small molecule peptide to create chimeric RGD peptides, (RGD-T-La [S] and RGD-T-La [FS]). Preliminary experiments showed that the new antitumor peptides had significant antitumor effects. After coupling to the chimeric RGD peptide, the targeted treatment of mouse melanoma was significantly improved. Our data demonstrate that the 4 peptides tested herein significantly inhibited the proliferation, migration, and invasion of B16F10 cells; with an increase in polypeptide concentration, the proportion of melanoma cells in the G0/G1 phase decreased or increased significantly, respectively, the reactive oxygen species (ROS) content increased significantly, the mitochondrial membrane potential decreased significantly, and the expression of pro-apoptotic Bax, Caspase-3, and Caspase-9 increased, and anti-apoptotic Bcl-2 decreased significantly. Tyr and MITF genes were significantly downregulated. In conclusion, the use of these new anti-tumor peptides, when combined with a chimeric RGD peptide, may increase ROS levels and decrease mitochondrial membrane potential by inhibiting the activity of mitochondria, thus releasing apoptosis-promoting factors in B16F10 cells. The present study describes a new potential strategy for the application of promising peptides in the treatment of various cancers.

为了评价融合表达抗菌肽TLN-58和人溶菌酶hLYZ双基因重组表达质粒的安全性,试验采用基因重组法将TLN-58和hLYZ基因片段克隆至pEGFP-N1载体,利用转染试剂GeneTwinTW将构建好的重组质粒转染HEK293细胞,RT-PCR验证重组真核质粒在细胞中表达情况;通过DAPI染色、AO/EB染色、CCK-8检测法和流式细胞术测定并分析hLYZ和TLN-58融合基因表达产物的细胞毒性.结果表明:成功构建重组真核质粒pEGFP-N1-hLYZ-TLN-58,当重组质粒DNA用量为1 μg且GeneTwinTW转染试剂用量为3 μL时,转染HEK293细胞24 h,为最佳转染条件,重组质粒可成功表达目的基因;DAPI染色和AO/EB染色显示,转染pEGFP-Nl-hLYZ-TLN-58质粒组细胞凋亡与对照组相比,无显著性差异;CCK-8试验测定细胞相对增殖率(RGR)为50％～74％,显示重组质粒的细胞毒性较小;流式细胞术检测发现重组质粒转染细胞与对照组细胞在G1、G2和S期所占的比例均差异不显著.结果表明,重组质粒的细胞毒性较小且对细胞周期无显著影响,为抗菌肽TLN-58和hLYZ的安全性及抗菌应用奠定了研究基础.

Melanoma is a common malignant skin tumor, which is the only fatal skin tumor at present. Melanoma has a high degree of malignancy and metastasis. The activity of modified Temporin-La (T-La) peptides from bullfrog skin were evaluated for antitumor activity and improved targeting in melanoma cells. The amino acid sequence of T-La was modified, resulting in the antitumor peptide, T-La (FS). T-La and T-La (FS) were coupled to the RGD small molecule polypeptide to form the chimeric peptides RGD-T-La and RGD-T-La (FS), respectively. The secondary structures for the peptides, evaluated using circular dichroism, were found to be α-helical. The structure of T-La was evaluated using bioinformatics. In addition, the antitumor effects of the modified peptide and the targeting of RGD chimeric peptide to the tumor in vivo and in vitro were analyzed. Antitumor activity was measured in vitro using the MTT assay. Tumor cells with high integrin αvβ3 expression were detected using flow cytometry, and tumor cells were screened for sensitivity to RGD-T-La (FS) to establish a tumor model in nude mice. The effects of the peptides on tumor cells were measured using laser confocal microscopy in real-time. The mechanism of the peptide antitumor activity in tumor cells was evaluated with scanning electron microscopy. B16 melanoma cells were the most sensitive to the peptides, for which the cell survival rate was 24.65% for 10 µg/ml RGD-T-La (FS). RGD-La (FS) had a rapid effect on tumor cells. RGD chimeric polypeptides exhibited site-targeting cytotoxic effects in tumor cells. In the B16 melanoma mouse model, the peptides exhibited antitumor effects against early melanoma development and induced tumor apoptosis, possibly by inhibiting VEGF and promoting caspase-3 expression. Overall, the present study provides a scientific basis for the application of small molecule antimicrobial peptides as targeted antitumor agents and lays the foundation for the clinical application of these peptides as antitumor drugs.

新农科建设是国家对高等农业院校提出的新任务和新要求,旨在培养一批批懂农业、爱农村、爱农民,具有服务三农意识和情怀的行业人才.落实立德树人根本任务的重要途径就是课程思政, 本文就在新农科建设背景下天津农学院《动物生物化学》课程思政建设和对教师的要求方面进行探讨.

为了提高难溶性药物烯丙孕素(altrenogest,ALT)的水溶性,本试验采用冷冻干燥法来制备烯丙孕素-羟丙基-β-环糊精(ALT-HP-β-CD)及其衍生物2,6-二甲基-β-环糊精(DIME-β-CD)包合物载药体系,并对ALT的线性关系和专属性、仪器的精密度以及包合物的回收率和稳定性进行了测定.以包合物的收率和包合物中ALT的包合率为评价指标,采用正交试验设计优选2种包合物的最佳制备条件,并使用傅里叶变换红外光谱法、热重分析法和显微镜成像法对所制得的ALT包合物进行表征分析,采用溶解度法测定包合物中ALT的溶解度.结果 表明,ALT在1～12μg/mL范围内具有较好的线性关系且专属性良好,仪器的精密度良好;加入0.1、0.2和0.3 mL ALT标准液的ALT-HP-β-CD包合物的平均回收率分别为97.78％、99.38％和99.90％,加入0.1、0.2和0.3 mL ALT标准液的ALT-DIME-β-CD包合物的平均回收率分别为93.86％、97.72％和94.93％;ALT-HP-β-CD包合物的最佳制备工艺为在55℃条件下,ALT与HP-β-CD的投料摩尔比为1∶7,包合时间为4h,溶液pH为8,溶剂水的加入量为110mL/g药物;ALT-DIME-β-CD包合物的最佳制备工艺为在55℃条件下,ALT与DIME-β-CD的投料摩尔比为1∶4,包合时间为4h,溶液pH为9,溶剂水的加入量为100 mL/g;经傅里叶变换红外光谱法、热重分析法和显微镜成像法表征,证实成功制得包合物;溶解度试验得出包合物的溶解度分别约为ALT原药的1012和1354倍,表明两种包合物均可有效增加ALT的溶解度.本试验包合物的制备方法简单,条件温和,易于产业化生产.

In this work, we present novel kinds of γ-Fe2O3@SiO2-NH2-CMC/MOF5 and γ-Fe2O3@SiO2-NH2-CMC/IRMOF3 magnetic metal–organic framework (MOF) nanoparticles which possess both magnetic characteristics and fluorescent properties. Here, [Zn4O(bdc)3] (MOF-5, bdc=1,4-benzenedicarboxylate) is a kind of shell. IRMOF3, a known MOF with a cubic topology prepared from Zn(NO3)2⋅4H2O and 2-amino-1,4-benzene dicarboxylic acid, is another kind of shell which is attractive due to its highly porous, crystalline structure and the presence of non-coordinating amino groups on the benzenedicarboxylate (bdc) linker, which are amenable to post-synthetic modification. γ-Fe2O3@SiO2-NH2-CMC magnetic nanoparticles (MNPs) could be prepared by covalent modification of sodium carboxymethyl cellulose (CMC). The structure of γ-Fe2O3 nanoparticles could be determined by X-ray powder diffraction (XRD). X-ray photoelectron spectroscopy (XPS) spectra could be used for the characterisation of γ-Fe2O3@SiO2-NH2, γ-Fe2O3@SiO2-NH2-CMC, γ-Fe2O3@SiO2-NH2-CMC/MOF5, and γ-Fe2O3@SiO2-NH2-CMC/IRMOF3 nanoparticles. Magnetic solid-phase extraction (MSPE) of enrofloxacin (Enr) experiments exhibited that, for γ-Fe2O3@SiO2-NH2-CMC/IRMOF3, the best effects of adsorption could be obtained at pH 4 and 6, while elution conditions of 0.1mol L−1 NaOH and 1% sodium dodecyl sulfate could achieve the best elution effect. The addition of Tb3+ ions could sensitise the fluorescence of Enr. At the same time, via the addition of Tb3+ ions, coordination could occur between nanoparticles and Tb3+ ions, which could be verified by XPS.

随机选择产奶期为(140±15)d的荷斯坦奶牛按照产奶量分成高产组和低产组,研究热应激对高产和低产奶牛血液生理指标、炎性因子和生产性能的影响.结果 显示,轻度热应激状态下,高产奶牛外周血淋巴炎性因子白细胞介素1β(IL-1β)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)均高于低产奶牛,且差异极显著(P＜0.01);高产奶牛的球蛋白(GLO)、总胆红素(TBIL)、血液尿素氮(BUN)、肌酐(CRE)、谷草转氨酶(AST)均高于低产奶牛,且差异显著(0.05＞P＞0.01);在生产性能方面,高产奶牛的产奶量下降最为明显,均值达到21％,极显著高于低产组(P＜0.01),乳脂肪、乳蛋白、乳酸和BUN均低于低产组,体细胞数则高于低产组,并且乳蛋白和乳汁BUN与低产组比较差异极显著(P＜0.01).结果 表明,高产奶牛受到热应激的损伤较低产奶牛严重,并在外周淋巴炎性因子、肝肾损伤、乳产量和乳品质方面表现尤为突出.