Ames Test of Protein-modified Enterococcus faecalis

The potential mutagenicity of protein-modified Enterococcus faecalis was evaluated by the Ames test. The test subject was designed with 0. 05,0. 5,5. 0,and 50. 0 mg/dish doses,and a control group was set. With Salmonella typhimurium mutant strains TA97,TA98,TA100 and TA102 as test strains,the Ames test was carried out with( +) or without(-) S9,and the number of revertant colonies was counted. The results showed that for the protein-modified E. faecalis in the case of + S9 and-S9,the average numbers of revertant colonies of the four test strains were less than two times of that of the negative control group,and no dose-response relationship was observed. The protein-modified E. faecalis was tested to be negative in the Ames test,indicating that the test substance was not mutagenic in vitro.

液相芯片多重检测技术在临床检验应用的研究进展

液相芯片多重检测技术是一种利用混悬在液相中的分类编码微球作为反应及信号检测载体的多重检测技术,它充分利用发展成熟的流式细胞术检测原理,能对临床大多数生物分子(如核酸、蛋白质等)进行高通量分析。该技术目前已在医学检验应用研究中广泛使用。本文着重归纳了液相芯片多重检测技术在呼吸系统、消化系统、生殖系统、神经系统、内分泌系统、泌尿系统、运动系统等各大系统疾病与核酸、蛋白质检测方面的临床检验应用研究,发现其性能高,有可观的应用前景。此外,将液相芯片多重检测技术与ELISA法、PCR法等传统方法进行比较后,发现液相芯片多重检测技术具有线性范围好、高通量、检测速度快、灵敏度高、特异性强、准确性高等优点,表明该技术更适用于临床疾病指标的筛查。

Influence of diet intake on liver function test

AIM To study the influence of diet intake on the result of liver function test. METHODS Blood samples from liver diseases ( n =100) and non liver diseases ( n =100) were taken at 07:00 in the morning (fasting state) and two hours after meal. Using Hitach 7150 automatic biochemistry analyser, ten liver function indexes (SB, TTT, ALT, AST, ALP, LDH, γ-GT, SP, A and G) were examined. RESULTS According to the SAS software system the differences were not significant between fasting state and after meal ( P =0 476-0 978). CONCLUSION Liver function test can be performed after meal.

Protein-protein Interaction Between Domains of PDZ and BAR from PICK1

Two DNA fragments encoding PDZ domain （21-110 residues） and BAR domain （ 150-360 residues） from PICK1 （1-416 residues） were amplified by PCR and then introduced into vectors, pET-32M and pMAL-e2X respectively to generate recombinant plasmids, pE-pdz and pM-bar. Having been separately transferred into the hosts E. coli BL21 and E. coli JM109, these two strains can express fusion proteins： His-tagged PDZ（PDZ domain） and maltose binding protein-BAR（ MBP-BAR domain） respectively, as confirmed by both SDS-PAGE and Wostem blotting. The interaction between these two domains is dose-dependence, as identified by a pull-down test. Moreover, it has been shown from the ELISA analysis that the actual amount of PDZ bound to MBP-BAR-amylose beads reaches （ 16 ± 0. 5）%, as calculated by the molar ratio of PDZ to MBP-BAR. In addition, the interaction between BAR（bait） and PDZ（prey） in vivo was also examined with a yeast two-hybrid system.

Preparation of Polyclonal Antibody against Human MxA Protein and Its Specificity to Diversified Myxovirus Resistant Protein A

Objective To study the human myxovirus resistant protein A （MxA）, a specifically induced peptide by interferon I, and to use its level as a diagnostic criterion for viral infections. Methods Anti-MxA antisera from immunized mice were prepared with the expressed MxA protein of pET32a-MxA in E. coli BL-21（DE3）. To confirm the antiserum activity and specificity, the expression product of BL21, wild type MxA pEGFP-CI-wMxA and site-directed mutant MxA pEGFP-Cl-mMxA（N589S） stably transfected 3T3 cells and induced A549 cells were detected by Western blot with the antisera using non-MxA transfected or non-IFN-[3 induced cells, intact A549, NIH 3T3 cells transfected with pEGFP-CI and pET32a （＋）-transformed BL-21 as controls. Results The antisera had specific positive immunoreactivity to the NIH3T3 cells transformed with pEGFP-CI-wMxA and pEGFP-CI-mMxA, INF-β induced A549 cells and BL21 proteins expressed with pET32a （＋）-MxA. The hybridization signals from IFN-β induced A549 cells depended on the IFN-β inducing concentrations. Meanwhile, immunohistochemical assay showed that NIH 3T3 cells with pEGFP-C 1-wMxA and pEGFP-C 1-mMxA had 〉 98% of positive cells at 1：50 dilution of the serum and A549 cells induced by 20 ng/mL IFN-[3 for 48 h showed 95% positive cells. pEGFP-Cl-transfected NIH 3T3 cells were all negative. Conclusion Anti-sera are highly specific to diversified MxAs. The antibody is detectable by Western blot, immunocytochemistry and immunofluorescence assay.

The development of a recombinant hybrid protein of Plasmodium falciparum and analysis of its antigenicity and protectivity

A hybrid gene encoding several putative protective epitopes from erythrocytic stage antigens (MSA1,MSA2 and RESA) of P. falciparum as well as exgenous T cell enhancer epitopes from interleukin-1 and tetanus toxin was synthesized chemically. This gene (named HGFC) was cloned and connected with another hybrid gene (HPFA) synthesized previously to make a bigger hybrid gene (HGFCAC). HGFC and HGFCAC were cloned in an expression vector pWR450-1 and transformed into E. Coli JM109. The engineered bacteria could express fusion proteins with molecular weights of 65 and 77 kDa after inducing with isopropylthio-β-D-galactoside (IPTG). The expression rate was about 35% of total bacterial proteins. The expressed products showed sepcific immunological reaction with rabbit antibodies against P. falciparum peptide Glu-Glu-Asn-Val-Glu-His-Asp-Ala (EENVEHDA)by Western blotting. The fusion proteins were pruified by precipitation with amonium sulfate. gel filtration and ion-exchange chromatography and the purity was 82%. The purified protein reacted specifically with mouse immune serum against falciparum blood stage antigens by dot enzyme-linked immunosorbent assay (dot-ELISA).The fusion protein was emulsified with Freund's complete adjuvant (FCA) and used to immunize rabbits. The immune serum can recognize P. falciparum erythrocytic stage antigens of Fcc-1/HN strain and Yunnan strain and had weak cross reaction with P. vivax,but had no reaction with P. cynomlogi and P. berghei antigens. The protective effect of the antibody was tested by in vitro inhibition test to cultured falciparum parasites. Preliminary results indicated that the immune sera could effectively reduce the invasion rates of the parasites to red blood cells and inhibit the growth of the in vitro cultured falciparum parasites. The inhibitory capacity of the immune sera to parasite invasion is enhanced as the amount of the sera increases and the incubation time of the sera with the parasites is prolonged.It was shown that after 72 h incubation at 20% concentration with the parasites, the serum can suppress the multiplication of P.falciparum growth in vitro to a level of 80%.The immune sera caused dispersion of the parasite cytoplasm,atrophy of parasites,agglutination of free merozoites and degeneration of schizonts.

13C Protein Oxidation in Breath: Is It Relevant for the Whole Body Protein Status?

Introduction: The kinetics of protein oxidation, monitored in breath, and its contribution to the whole body protein status is not well established. Objectives: To analyze protein oxidation in various metabolic conditions we developed/validated a 13C-protein oxidation breath test using low enriched milk proteins. Method/Design: 30 g of naturally labeled 13C-milk proteins were consumed by young healthy volunteers. Breath samples were taken every 10 min and 13CO2 was measured by Isotope Ratio Mass Spectrometry. To calculate the amount of oxidized substrate we used: substrate dose, molecular weight and 13C enrichment of the substrate, number of carbon atoms in a substrate molecule, and estimated CO2-production of the subject based on body surface area. Results: We demonstrated that in 255 min 20% ± 3% (mean ± SD) of the milk protein was oxidized compared to 18% ± 1% of 30 g glucose. Postprandial kinetics of oxidation of whey (rapidly digestible protein) and casein (slowly digestible protein) derived from our breath test were comparable to literature data regarding the kinetics of appearance of amino acids in blood. Oxidation of milk proteins was faster than that of milk lipids (peak oxidation 120 and 290 minutes, respectively). After a 3-day protein restricted diet (~10 g of protein/day) a decrease of 31% ± 18% in milk protein oxidation was observed compared to a normal diet. Conclusions: Protein oxidation, which can be easily monitored in breath, is a significant factor in protein metabolism. With our technique we are able to characterize changes in overall protein oxidation under various meta-bolic conditions such as a protein restricted diet, which could be relevant for defining optimal protein intake under various conditions. Measuring protein oxidation in new-born might be relevant to establish its contribution to the protein status and its age-dependent development.

腕手部腱鞘结核临床误诊分析

目的探讨腕手部腱鞘结核临床误诊原因及防范措施。方法回顾性分析2023年4月至2024年4月收治的曾误诊的腕手部腱鞘结核3例的临床资料。结果1例右腕肿痛,拇指肿痛,根据相关检查结果及术后病理检查“腕部考虑滑膜炎,拇指考虑骨髓炎,结核不排除”,因腕部肿胀、疼痛加重再次入院,考虑结核。行抗结核治疗病情得到控制,出院诊断为“右腕手部腱鞘结核”。误诊时间3个月。外院继续抗结核治疗病情控制后行皮瓣手术治疗,随访未见结核复发,腕关节和屈指功能受限。1例左拇指掌侧肿物压痛加重、活动受限,考虑“指尖脓肿”,行指尖脓肿切开引流术后脓肿反复发作。结合病史及入院查体考虑“慢性感染”行扩创引流术,术后病理确诊为“手部腱鞘结核”。误诊时间11个月。确诊后行病灶清除术,随访未见结核复发,左拇指伸屈功能满意。1例左中指近节掌侧肿物,外院考虑为“狭窄性腱鞘炎”,予复方倍他米松注射液局部注射治疗,效果不佳。结合入院查体及相关检查结果,考虑结核感染,行病灶清除术,术后病理确诊为“手部腱鞘滑膜增殖型结核”。误诊时间14个月。确诊后行病灶清除术,随访未见结核复发,左手中指屈指活动功能满意。结论腕手部腱鞘结核因临床特征不典型,早期缺乏特异性诊断指标,误诊率较高,对长期对症治疗无效的腕手部病变应警惕腱鞘结核,尽早行病灶清除术及病理检查,以减少误诊。

豌豆蛋白酶解加工工艺优化及其生物活性研究

豌豆是重要的豆类栽培作物,蛋白质含量较高,是植物蛋白的主要来源之一,但目前大部分豌豆用于制作淀粉,副产物中的豌豆蛋白提取率较低,常常被用于制作饲料或作为生产废料,使得大量豌豆资源被浪费。该研究基于此,通过单因素试验和正交试验对豌豆蛋白酶解工艺进行研究和优化,结果表明,豌豆蛋白最佳酶解工艺为物料含水量30%、温度70℃、模具孔径8 mm和螺杆转速190 r/min,此时豌豆蛋白水解度为38.58%。另外,研究豌豆蛋白酶解后得到的水解物的生物活性功效,发现其具有明显的抗疲劳功效。

Gel Electrophoresis of Proteins for the Identification of Crop Varieties

With the development of the international trade and agricultural science and technology, especially after the execution of the rules on protection of new plant varieties, considerable emphasis has been placed on variety identification. Many evidences have suggested that gel electrophoresis have great influence on this area. This paper reviewed study status of various gel electrophoresis, including development of the meth-

减蛋综合征病毒抗体胶体金免疫层析试纸条的研制及初步应用

为建立快速检测减蛋综合征病毒(EDSV)抗体的方法,基于EDSV的Fiber蛋白,制备快速检测EDSV抗体的免疫层析试纸条,为养禽业提供针对病原微生物的感染预警及免疫评估。利用胶体金标记EDSV Fiber蛋白抗原为探针,将羊抗鸡IgG和抗Fiber蛋白的抗体包被到硝酸纤维膜上,分别作为质控线和检测线,对家禽EDSV抗体水平进行监测。结果表明,制备的EDSV免疫层析试纸条具有高度特异性,与其他家禽病毒抗体无交叉反应,仅与EDSV抗体反应,在试纸条上产生可见的检测线;并且制备的试纸条具有高度稳定性,在室温条件下可至少保存6个月。应用制备的检测EDSV抗体的免疫层析试纸条对从河南、安徽、山东等地养鸡场采集的576份鸡血清样本检测,与血凝抑制试验(HI)结果进行平行比较,二者的Kappa值为0.878,具有良好一致性。综上,制备的检测ESDV抗体的免疫层析试纸条具有高度的特异性、敏感性、稳定性和易操作性,对EDSV抗体的临床检测具有实际应用价值。

In-vivo Mutagenicity of Protein-modified Enterococcus faecalis

The mutagenicity of the protein-modified Enterococcus faecalis was evaluated by a mouse bone marrow micronucleus test and a mouse sperm abnormality test.The test substance was designed with three dose groups (1,2 and 5 g/kg·bw) and intragastrically administrated,with cyclophosphamide as a positive control and normal saline as a normal control.The micronucleus rate and sperm abnormality rate were measured.The results showed that the micronucleus rates and sperm abnormality rates in the different dose groups were not significantly different from those in normal control group ( P >0.05),while the positive control group was significantly higher than the normal control group ( P <0.01).The conclusion is that the protein-modified E.faecalis was tested to be negative in both the mouse bone marrow micronucleus test and mouse sperm abnormality test,suggesting that it has no mutagenicity in vivo.

Up-regulation and time course of protein kinase C immunoreactivity during persistent inflammation of the rat spinal cord

BACKGROUND： It has been reported that activation and/or translocation of protein kinase C （PKC） is related to hyperalgesia, and changes in PKC expression in the dorsal horn of spinal cord take place during inflammatory pain. OBJECTIVE： To observe PKC changes in the dorsal horn of spinal cord using immunohistochemistry and to measure the time-course during persistent pain produced by chemical stimulation with a right hind-paw injection of formalin. DESIGN： Randomized controlled animal experiment. SETTING： Institute of Basic Medical Science, Hebei Medical University MATERIALS： The present experiment was performed at the Department of Pathophysiology, Institute of Basic Medical Science, Hebei Medical University between September 2000 and June 2002. Forty-two Sprague-Dawley rats, weighing 260-280 g, irrespective of gender, were provided by the Center of Animal Experimentation at Hebei Medical University. PKC antibody was provided by Sigma, USA. Immunohistochemistry kits were purchased from Zhongshan Biotechnology Company, Beijing. HPIAS-1000 definition multicolor system was provided by Qianping Wuxiang Project Company of Tongji Medical University. Animal use during experimentation was consistent with the standards of Animal Ethics Committee. METHODS： Sprague-Dawley rats were divided randomly into control （n = 6） and experimental groups （n = 36）. Experimental rats were given an intracutaneous injection of 5% formalin into the planta surface of the right hind-paw. Animals with inflammatory pain were anesthetized and sacrificed to obtain the L5 spinal region at 1, 3, 12 hours, 1, 3, and 7 days after formalin treatment, with 6 rats in each time group. The spinal cords at the L5 region were collected from the control group following sodium chloride injections into the planta surface of the right hind-paw, identical to the experimental group. MAIN OUTCOME MEASURES： Pain reaction of experimental rats after formalin treatment. PKC-positive neurons, and distribution of PKC-immunoreactive particles, in the ipsi- and contralateral dorsal horn were investigated during different stages of inflammatory pain using immunohistochemistry. RESULTS： All 42 rats were included in the final analysis, without any loss. Pain reaction： consistent with previous findings, it was determined that a unilateral injection of formalin into the hind-paw resulted in significant edema and induced a series of nociceptive responses, such as licking, biting, or shaking the injected paw. The maximal inflammation change was observed 1 day after formalin injection and changes did not disappear until the day 7. Number of the PKC positive neurons： results demonstrated that the number of PKC immunoreactive neurons in the dorsal horn increased slightly after formalin injection at 1 hour, compared with the control group. PKC immunoreactivity was up-regulated at day 1, reduced at day 3, and appeared to recover at day 7. The number of PKC-positive neurons in the contralateral side was less than the ipsilateral side at each time sampled. Distribution of PKC immunoparticles over the neurons： PKC immunoreactivity was observed in the nucleus and cytoplasm, as well as on or near the membrane of neurons and synaptosomes in the spinal cord of the control group. PKC activated and translocated from nucleus to the membrane-associated site following formalin treatment. Significant changes were observed at 1 hour and 1 day. The intensity of staining was stronger in the ipsilateral side than the contralateral side at all time points following formalin injection （P 〈 0.01）, whereas the expression patterns of PKC immunoreactivity in the nuclei were very similar in the right and left hemispheres. CONCLUSION： PKC expression in the dorsal horn of the spinal cord peaked at 1 hour and 24 hours, and was very obvious at 24 hours. Protein kinase C expression in the spinal cord increased bilaterally, although it was greater in the ipsilateral hemisphere. In addition, PKC expression at the neuronal membrane and synaptosome was significantly increased. These results indicate that PKC expression is activated in the dorsal horn of the spinal cord during hyperalgesia.

亚硝酸盐对焦酚红法检测24 h尿液总蛋白的干扰分析

目的探讨亚硝酸盐对于焦酚红法检测24 h尿液总蛋白的干扰效应,并评估维生素C纠正干扰的可行性。方法根据美国临床和实验室标准协会(CLSI)EP7-A3文件,选取24 h尿液总蛋白定量结果为150 mg/L、500 mg/L和1000 mg/L的新鲜尿液标本作为对照样本,并配制含不同浓度亚硝酸钠的干扰物样本。利用配对差异实验确认亚硝酸盐的干扰作用,并通过剂量效应实验明确亚硝酸盐浓度与干扰程度的关系。在终浓度为200μg/mL亚硝酸钠存在的情况下,评估不同浓度维生素C纠正干扰的效果。同时收集61例亚硝酸盐阳性和40例亚硝酸盐阴性的临床标本,比较两组标本维生素C纠正前后的相对差值,评估其临床应用价值。结果配对差异实验中200μg/mL亚硝酸钠对150 mg/L和500 mg/L两个浓度的尿总蛋白测定分别存在-157.8%和-36.2%的相对干扰,显著大于1/2TEa(22%),而对于高浓度1000 mg/L的尿总蛋白虽存在-20.5%的负干扰,但在可接受范围内。剂量效应实验结果显示随着尿液中亚硝酸盐浓度的增加,尿总蛋白检测所受负干扰作用亦逐渐增大。在终浓度为200μg/mL亚硝酸钠存在的情况下,添加0.2 mg/mL的维生素C可分别将150 mg/L和500 mg/L的尿总蛋白纠正至148 mg/L(-1.1%)和402 mg/L(-19.5%),均处于可接受范围内。临床标本中亚硝酸盐阳性组通过维生素C纠正产生的相对差值显著高于亚硝酸盐阴性组(P<0.01)。结论亚硝酸盐对于焦酚红法检测尿液总蛋白存在负干扰,尤其是在尿总蛋白150 mg/L情况下,需引起临床实验室的关注。添加0.2 mg/mL维生素C可有效纠正低浓度尿总蛋白标本中亚硝酸盐的干扰作用,具有一定的临床应用价值。

恩格列净治疗射血分数降低心力衰竭患者的效果

目的 观察钠—葡萄糖协同转运蛋白2(SGLT2)抑制剂恩格列净治疗射血分数降低慢性心力衰竭(HF-rEF)的效果。方法 将2019年6月—2022年1月吉林市市中心医院心血管内科收治的94例HF-rEF患者按照随机数字表法分为对照组(47例)和观察组(47例)。其中,对照组采用常规抗心力衰竭治疗,观察组在常规治疗基础上加恩格列净,比较治疗前、后两组患者6min步行距离(6MWD)、氨基末端脑钠肽前体(NT-proBNP)、肿瘤坏死因子α(TNF-α)、超敏C反应蛋白(hs-CRP)、hs-cTnT、左心室射血分数(LVEF)、左室舒张末期内径(LVIDd)、左室收缩末期内径(LVIDs)水平、心输出量(CO)、E/A值、再住院率以及不良反应。结果 观察组6MWD、NT-proBNP、TNF-α、hs-CRP、hs-cTnT、LVEF、LVIDd、心输出量(CO)、E/A值、临床疗效、再住院率改善情况明显优于对照组(P<0.05)。两组的LVIDs、不良反应发生率对比,差异无统计学意义(P>0.05)。结论 在HF-rEF患者中,恩格列净治疗射血分数降低型心力衰竭疗效确切,可以显著地改善患者临床症状、心脏功能以及生活质量,不良反应少,安全性高。

不同体质指数的非酒精性脂肪性肝病患者的心功能及三大底物消耗特点

目的分析不同体质指数的非酒精性脂肪性肝病(NAFLD)患者的心功能及三大底物消耗特点。方法选取45例NAFLD患者,根据体质指数将其分为正常组(15例)、超重组(13例)和肥胖组(17例)。采用心肺运动试验(CPET)测定3组患者在运动达无氧阈时及达最大运动时的摄氧量、碳水化合物能量消耗、脂肪能量消耗、蛋白质能量消耗。采用Weber心功能评级标准评估3组患者的心功能进行评定。结果3组患者Weber心功能分级均为B级。达最大运动时,正常组、超重组、肥胖组患者的摄氧量依次降低(P<0.05);运动达无氧阈时,肥胖组患者的碳水化合物能量消耗高于超重组和正常组(P<0.05),但超重组和正常组之间差异无统计学意义(P?0.05);运动达无氧阈时,正常组、超重组、肥胖组患者的蛋白质能量消耗依次增加(P<0.05)。但运动达无氧阈和最大运动时,3组患者的脂肪能量消耗差异无统计学意义(P?0.05)。结论NAFLD患者均存在轻度至中度心功能损害。在进行较高强度运动时,体质指数越大的NAFLD患者的摄氧能力越低,心脏运动耐力越差;在进行中低强度运动时,高体质指数的NAFLD患者所需能量倾向于由碳水化合物代谢和蛋白质代谢提供;无论运动强度高低,NAFLD患者的脂肪氧化代谢能量消耗基本不受体质指数影响。

弱电场中油菜籽蛋白提取优化及结构测定

以冷榨油菜籽为原料,将弱电场引入到油菜籽蛋白的提取中,使用单因素和正交试验结合法对弱电场中油菜籽蛋白提取工艺进行优化。结果表明:油菜籽蛋白提取因素对提取率影响的主次顺序为电压>温度>料液比,最佳提取工艺为电场电压15 V、水污温度30℃、料液比1∶10(g/mL),在此条件下提取率可达7.59%。使用红外光谱及元素分析对产品进行分析,显示提取产物中存在明显的酰胺Ⅰ、Ⅱ、Ⅲ带,其蛋白纯度为88.75%;最后测定了最佳条件提取产物的扫描电镜,结果显示蛋白质成不规则颗粒状。本研究结果证明使用电场絮凝,可获得纯度较高的蛋白质,此研究可为其他种类蛋白质在弱电场中的提取提供一定的参考。

紫苏籽蛋白提取工艺优化及抗疲劳活性研究

紫苏籽富含蛋白质和氨基酸,具有较高的开发价值,该研究利用单因素试验和正交试验对紫苏籽蛋白的提取工艺进行研究和优化,研究结果表明,紫苏籽蛋白的最佳提取工艺为料液比例1∶20、碱提pH 10、碱提时间20 min和碱提温度50℃,此时紫苏籽蛋白提取率最高,为54.25%。通过Design-Expert 12软件对正交试验数据进行多元回归拟合分析,获得紫苏籽蛋白提取工艺参数的回归模型为Y=53.12+0.45A+1.19B+1.39C-0.051AB+1.61AC-1.37BC-2.41A~2-0.81B~2-2.21C~2,此回归模型的P值<0.001,说明试验值与真实值之间的误差极小。此外,还对紫苏籽蛋白的抗疲劳生物活性进行了研究,结果表明适量的紫苏籽蛋白具有较好的抗疲劳活性。

异功散中人参皂苷类成分在脾虚大鼠模型肠吸收动力学变化及其陈皮的影响

目的基于脾虚大鼠模型探讨异功散中陈皮对人参皂苷类成分肠吸收变化的影响及其影响是否与P-gp蛋白外排作用有关。方法分组设计加入P-gp蛋白激动剂利福平与抑制剂维拉帕米,将36只SD大鼠随机分为空白对照组(6只)与模型组(30只),予以皮下注射利血平建立脾虚模型后将模型组分为异功散组(Y组)、去陈皮异功散组(Y-C组)、异功散利福平组(Y+R组)、去陈皮异功散利福平组(Y-C+R组)、去陈皮异功散维拉帕米组(Y-C+V组),以人参皂苷Rb1、人参皂苷Re及人参皂苷Rg1为指标成分,进行在体单向肠灌流实验,采用HPLC-MS测定指标成分含量并计算肠吸收动力学参数有效渗透系数(P_(eff))与吸收速率常数(K_(a))。结果与Y组相比,Y-C组中人参皂苷Rb1和人参皂苷Re在多个灌流时段的P_(eff)显著降低,Y+R组中人参皂苷Rb1、人参皂苷Re及人参皂苷Rg1的P_(eff)和K_(a)在多个灌流时段降低,表明陈皮促进人参皂苷Rb1和人参皂苷Re肠吸收且该作用与P-gp蛋白活性有关,但未能影响人参皂苷Rg1的肠吸收;与Y-C组相比,Y-C+V组中P-gp蛋白抑制剂维拉帕米使人参皂苷Rb1和人参皂苷Re在多个灌流时段P_(eff)显著升高,而Y-C+R组中P-gp蛋白激动剂利福平使人参皂苷Rb1、人参皂苷Re及人参皂苷Rg1的P_(eff)和K_(a)在多个灌流时段显著降低,说明无陈皮干预下,人参皂苷Rb1、人参皂苷Re及人参皂苷Rg1也可能是P-gp蛋白的底物。结论异功散中陈皮通过发挥抑制P-gp蛋白活性的类维拉帕米作用来促进人参皂苷Rb1和人参皂苷Re肠吸收。

基于近红外光谱技术的香榧蛋白质和脂肪含量无损检测方法研究

为丰富香榧品质把控的技术手段,本研究利用近红外光谱分析技术建立了香榧存储时间及条件的定性分析模型,同时结合化学计量方法建立了香榧蛋白质和脂肪的定量分析模型。对光谱进行预处理后选取特征波长,基于遗传算法(Genetic Algorithm,GA)和多元散射校正(Multiplicative Scatter Correction,MSC)算法建立的卷积神经网络模型(Convolutional Neural Networks,CNN)模型鉴别准确率达到99.2%,能够较好区分不同存储时间条件的香榧;建立偏最小二乘法(Partial Least Squares,PLS)、径向基函数神经网络(Radial Basis Function Neural Network,RBF)和极限学习机(Extreme Learning Machine,ELM)模型,对比分析采用竞争性自适应重加权采样法(Competitive Adapative Reweighted Sampling,CARS)作为光谱特征筛选方法,蛋白质和脂肪的特征个数分别为41和56,大大提升了运算效率。实验结果显示,使用二阶导数(Second Derivative,D2)进行预处理、使用CARS方法建立的D2-CARS-PLS模型为最优模型,在香榧蛋白质和脂肪含量的预测中都取得较好效果,决定系数(Coefficient of Determination,R^(2))分别为0.977和0.984。研究结果表明,近红外光谱技术在香榧品质的快速无损检测方面具有潜力,提供了一种可靠的香榧品质分析方法。