Gln与Ala-Gln对缓解LPS诱导动物免疫应激的研究进展

谷氨酰胺(glutamine,Gln)又称α-氨基戊酰胺酸、谷氨酸-5-酰胺,是一种非必需氨基酸,在机体中发挥重要作用,被认为是一种功能性氨基酸,通常以丙氨酰-谷氨酰胺(alanyl-glutamine,Ala-Gln)形式作为饲料的添加剂。Gln与Ala-Gln不仅能促进畜禽和水产动物生长,提高机体抗氧化、免疫能力,维持肠道健康,对缓解机体免疫应激也发挥着重要作用。文章通过探讨在饲料中添加Gln与Ala-Gln对动物的影响,阐述其缓解免疫应激的作用机理,为Gln、Ala-Gln作为饲料添加剂应用提供理论依据,同时为进一步研究缓解免疫应激的作用机制提供参考。

Environmental enrichment in combination with Bifidobacterium breve HNXY26M4 intervention amplifies neuroprotective benefits in a mouse model of Alzheimer's disease by modulating glutamine metabolism of the gut microbiome

The gut microbiota-brain axis has emerged as a novel target for Alzheimer's disease(AD),a neurodegenerative disease characterised by behavioural and cognitive impairment.However,most previous microbiome-based intervention studies have focused on single factors and yielded only modest cognitive improvements.Here,we proposed a multidomain intervention strategy that combined Bifidobacterium breve treatment with environmental enrichment(EE)training.In this study,we found that compared with EE or B.breve treatment alone,B.breve intervention combined with EE amplified its neuroprotective effects on AD mice,as reflected by improved cognition,inhibited neuroinflammation and enhanced synaptic function.Moreover,using microbiome and metabolome profiling,we found that the combination of B.breve and EE treatment restored AD-related gut microbiota dysbiosis and reversed microbial metabolite changes.Finally,by integrating behavioural and neurological data with metabolomic profiles,we revealed that the underlying mechanism may involve the modulation of microbiota-derived glutamine metabolism via gut-brain interactions.Collectively,combined B.breve intervention with EE treatment can alleviate AD-related cognitive impairment and improve brain function by regulating glutamine metabolism of the gut microbiome.Our findings provide a promising multidomain intervention strategy,with a combination of dietary microbiome-based and lifestyle-targeted interventions,to promote brain function and delay the progression of AD.

Effects of Supplemental Glutamine and Lysine on Growth Performance of Broiler Chickens

The optimum levels of Lysine and Glutamine needed for growth performance and maintenance of the chicken broilers were evaluated in a randomized 3 × 4 factorial arrangement of dietary treatments. The battery cages measured 99 × 66 × 25 cm that can be sufficient for 5 birds. Day old Chicken broilers totaling 180 were assigned to dietary treatments comprising of 3 concentrations of Lysine (0.85, 1.14, and 1.42) each in combination with 4 concentrations of Glutamine (0, 1, 2, and 3). Each dietary treatment was replicated 3 times and each replication had 5 birds. The birds were given feed and water ad libitum with a 23-hour light regimen for a period of 4 weeks. Then, the experimental birds were evaluated for body weight gain, feed consumption, and feed conversion in order to determine their optimum requirement for dietary Lysine and Glutamine. Based on the findings of this study, the highest performance was observed in birds fed the diet supplemented with 1.42 lysine and 1% glutamine, but the highest improvement in feed conversion was observed in diet contain 1.14 and 1.42 with 1% and 3% glutamine, respectively. Birds fed 1.42 lysine and 1% glutamine had the highest total body weight gain and feed consumption. The lysine requirements in the diet for Chicken are between 1.14 and 1.42 with glutamine level of 1%.

Glutamine supplementation attenuates intestinal apoptosis by inducing heat shock protein 70 in heatstroke rats

BACKGROUND:Heatstroke is the most hazardous heat-related illness and has a high fatality rate.We investigated whether glutamine supplementation could have a protective effect on heatstroke rats.METHODS:Twenty-five 12-week-old male Wistar rats(weight 305±16 g)were randomly divided into a control group(n=5),heatstroke(HS)group(n=10),and heatstroke+glutamine(HSG)group(n=10).Seven days before heat exposure,glutamine(0.4 g/[kg·d])was administered to the rats in the HSG group by gavage every day.Three hours after heat exposure,serum samples were collected to detect white blood cells,coagulation indicators,blood biochemical indicators,and inflammatory cytokines in the rats.The small intestine tissue was stained to analyze pathological structural changes and apoptosis.Finally,immunohistochemistry and Western blotting were used to analyze the expression levels of heat shock protein 70(HSP70).Multiple comparisons were analyzed by using one-way analysis of variance,and the Bonferroni test was conducted for the post hoc comparisons.RESULTS:After heat exposure,the core temperature of the HS group(40.65±0.31°C)was higher than the criterion of heatstroke,whereas the core temperature of the HSG group(39.45±0.14°C)was lower than the criterion.Glutamine supplementation restored the increased white blood cells,coagulation indicators,blood biochemical indicators,and inflammatory cytokines that were induced by heatstroke to normal levels.The intestinal mucosa was injured,and the structure of tight junctions was damaged in the HS group;however,the structure of intestinal mucosal epithelial cells was stable in the HSG group.Glutamine supplementation alleviated intestinal apoptosis and up-regulated HSP70 expression.CONCLUSION:Glutamine supplementation may alleviate intestinal apoptosis by inducing the expression of HSP70 and have a protective effect on heatstroke rats.

Characterization of prognosis and immune infiltration by a novel glutamine metabolism-related model in cutaneous melanoma

Glutamine metabolism(GM)plays an important role in tumor growth and proliferation.Skin cutaneous melanoma(SKCM)is a glutamine-dependent cancer.However,the molecular characteristics and action mechanism of GM on SKCM remain unclear.Therefore,we aimed to explore the effects of GM-related genes on survival,clinicopathological characteristics,and the tumor microenvironment in SKCM.In this study,682 SKCM samples were obtained from the Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.Consensus clustering was used to classify SKCM samples into distinct subtypes based on 41 GM-related genes.Differences in survival,immune infiltration,clinical characteristics,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways as well as differentially expressed genes(DEGs)between subgroups were evaluated.A prognostic model was constructed according to prognostic DEGs.Differential analyses in survival,immune infiltration,tumor microenvironment(TME),tumor mutation burden(TMB),stemness,and drug sensitivity between risk groups were conducted.We identified two distinct GM-related subtypes on SKCM and found that GM-related gene alterations were associated with survival probability,clinical features,biological function,and immune infiltration.Then a risk model based on six DEGs(IL18,SEMA6A,PAEP,TNFRSF17,AIM2,and CXCL10)was constructed and validated for predicting overall survival in SKCM patients.The results showed that the risk score was negatively correlated with CD8+T cells,activated CD4+memory T cells,M1 macrophages,andγδT cells.The group with a low-risk score was accompanied by a better survival rate with higher TME scores and lower stemness index.Moreover,the group with high-and low-risk score had a significant difference with the sensitivity of 75 drugs(p<0.001).Overall,distinct subtypes in SKCM patients based on GM-related genes were identified and the risk model was constructed,which might contribute to prognosis prediction,guide clinical therapy,and develop novel therapeutic strategies.

Glutamine addiction and therapeutic strategies in pancreatic cancer

Pancreatic cancer remains one of the most lethal diseases worldwide owing to its late diagnosis,early metastasis,and poor prognosis.Because current therapeutic options are limited,there is an urgent need to investigate novel targeted treatment strategies.Pancreatic cancer faces significant metabolic challenges,principally hypoxia and nutrient deprivation,due to specific microenvironmental constraints,including an extensive desmoplastic stromal reaction.Pancreatic cancer cells have been shown to rewire their metabolism and energy production networks to support rapid survival and proliferation.Increased glucose uptake and glycolytic pathway activity during this process have been extensively described.However,growing evidence suggests that pancreatic cancer cells are glutamine addicted.As a nitrogen source,glutamine directly(or indirectly via glutamate conversion)contributes to many anabolic processes in pancreatic cancer,including amino acids,nucleobases,and hexosamine biosynthesis.It also plays an important role in redox homeostasis,and when converted toα-ketoglutarate,glutamine serves as an energy and anaplerotic carbon source,replenishing the tricarboxylic acid cycle intermediates.The present study aims to provide a comprehensive overview of glutamine metabolic reprogramming in pancreatic cancer,focusing on potential therapeutic approaches targeting glutamine metabolism in pancreatic cancer.

Methods for the Determination of Stable Isotopes of Carbon and Nitrogen Directly in Valine, Proline, Glutamine, and Glutamic Acid

Amino acids are very important compounds for the body and are involved in important functions that keep us healthy. Amino acids are essential components such as valine, proline, glutamine and glutamic acid. They can be synthesized either naturally or artificially. To examine the metabolism and regulate the synthesis process, compounds labeled with nitrogen or carbon isotopes need to be used. These isotopic compounds allow for more extensive research and enable studies that would otherwise be impossible. However, their use is dependent on the availability of simple, efficient methods for isotopic analysis. Currently, the determination of the atomic fraction of carbon and nitrogen isotopes is only possible through their conversion into molecular nitrogen or carbon monoxide or carbon dioxide. This leads to the loss of information about isotopic enrichment in specific centers of the molecule. This article explores a new direct approach to determining the atomic fraction of carbon and nitrogen isotopes in the isotope-modified or identical centers of these compounds. This method eliminates the transfer process and dilution due to nitrogen and carbon impurities. It is now possible to simultaneously determine the atomic fraction of nitrogen and carbon isotopes in the research substance. This method can be applied to amino acids, making it an effective tool for proposing new research methods. Several articles [1] [2] [3] have proposed similar methods for organic compounds and amino acids.

Prognostic model and treatment plan analysis of hepatocellular carcinoma based on genes related to glutamine metabolism

Objective:To identify the prognosis of hepatocellular carcinoma(HCC)and the effect of anti-cancer drug therapy by screening glutamine metabolism-related signature genes because glutamine metabolism plays an important role in tumor development.Methods:We obtained gene expression samples of normal liver tissue and hepatocellular carcinoma from the TCGA database and GEO database,screened for differentially expressed glutamine metabolismrelated genes(GMRGs),constructed a prognostic model by lasso regression and step cox analysis,and assessed the differences in drug sensitivity between high-and low-risk groups.Results:We screened 23 differentially expressed GMRGs by differential analysis,and correlation loop plots and PPI protein interaction networks indicated that these differential genes were strongly correlated.The four most characterized genes(CAD,PPAT,PYCR3,and SLC7A11)were obtained by lasso regression and step cox,and a risk model was constructed and confirmed to have reliable predictive power in the TCGA dataset and GEO dataset.Finally,immunotherapy is better in the high-risk group than in the low-risk group,and chemotherapy and targeted drug therapy are better in the low-risk group than in the high-risk group.Conclusion:In conclusion,we have developed a reliable prognostic risk model characterized by glutamine metabolism-related genes,which may provide a viable basis for the prognosis and Treatment options of HCC patients.

Effects of Neuromuscular Electrical Stimulation in Combination with Glutamine Administration on Skeletal Muscle Atrophy in Colon-26 Tumor-Bearing Mice

The depressed protein synthetic response,a phenomenon termed anabolic resistance,has been shown to be involved in muscle wasting induced by cancer cachexia.Moreover,a positive relationship between the protein synthetic rate and intracellular glutamine(GLN)concentration has been found in skeletal muscles.This study investigated the effects of neuromuscular electrical stimulation(ES)and GLN administration on muscle wasting and GLN metabolism in colon-26(C-26)tumor-bearing mice.CD2F1 mice were divided into 8 groups:control(CNT),CNT+ES,CNT+GLN,CNT+ES+GLN,C-26,C-26+ES,C-26+GLN,C-26+ES+GLN.Cancer cachexia was induced by subcutaneous injection of C-26 cells and developed for four weeks.ES was performed on the left plantar flexor muscles every other day,and GLN(1 g/kg)was administered daily intraperitoneally starting one day after the C-26 injection.Tumor-free body mass and fast-twitch gastrocnemius(Gas)muscle weight were lower in the C-26 group than in the CNT group(-19%and-17%,respectively).Neither ES training nor GLN administration,alone or in combination,ameliorated the loss of Gas muscle weight in the C-26 mice.However,ES training in combination with GLN administration inhibited the increased expression of GLN synthetase(GS)in the C-26 muscles.Thus,it is likely that GLN plays a critical role in muscle protein metabolism and,therefore,can be targeted as a tentative treatment of cancer cachexia.

谷氨酰胺酶抑制剂CB-839介导T细胞效应抑制肺癌细胞中αKGA、Gln转化的作用机制

目的研究谷氨酰胺酶抑制剂CB-839(简称CB-839)介导T细胞效应抑制肺癌细胞α-酮戊二酸(αKGA)、谷氨酰胺(Gln)转化的作用机制。方法10只SPF级健康SD裸鼠均建立肺癌动物模型,分为模型组及抑制剂组,模型组裸鼠常规饲养;抑制剂组裸鼠皮下注射CD-839,测量两种肿瘤体积。人肺癌细胞A549购自上海匹拓公司,将肺癌细胞分为Ⅰ组(肺癌细胞常规培养)、Ⅱ组(肺癌细胞+0.25μmol/L浓度CB-839)、Ⅲ组(肺癌细胞+0.50μmol/L浓度CB-839)、Ⅳ组(肺癌细胞+1.00μmol/L浓度CB-839)。MTT法测A549细胞增殖,流式细胞仪测A549细胞凋亡及CD80、CD86、主要组织相容性复合体Ⅱ(MHCⅡ)水平,RT-qPCR测谷氨酸脱氢酶(GLUD1)mRNA、谷氨酰胺酶(GLS)mRNA水平,αKGA试剂盒测αKGA水平。结果培养24、48及72 h时Ⅰ组肺癌A549细胞吸光度(A值)高于Ⅱ组,差异有统计学意义(P<0.05);培养24、48及72 h时Ⅳ组肺癌A549细胞A值与Ⅲ组比较,明显降低,差异有统计学意义(P<0.05)。Ⅰ、Ⅱ、Ⅲ及Ⅳ组肺癌A549细胞凋亡率分别为(3.02±0.39)%、(4.72±0.52)%、(7.95±0.84)%及(13.22±1.28)%。与Ⅲ组相比,Ⅳ组肺癌A549细胞中CD80、CD86、MHCⅡ水平升高,差异均有统计学意义(P<0.05)。Ⅳ组肺癌A549细胞中αKGA水平与Ⅲ组比较,明显降低,差异均有统计学意义(P<0.05)。GLUD1 mRNA与GLS mRNA呈正相关(r=0.671,P<0.001),GLUD1 mRNA与αKGA呈正相关(r=0.708,P<0.001)。GLS mRNA与αKGA呈正相关(r=0.671,P<0.001)。结论CB-839可能通过介导T淋巴效应提高CD80、CD86、MHCⅡ水平,抑制αKGA及Gln相关基因转化,从而降低肺癌细胞活性,促进其凋亡,为今后肺癌的临床治疗及新药研发提供参考依据。

谷氨酰胺转氨酶对板栗粉面团理化特性的影响

为改善板栗粉在无麸质食品领域的品质特性及加工性能,考察谷氨酰胺转氨酶(glutamine transaminase,TG)添加量分别为0、0.9、1.8、2.7、3.6 U/g(按板栗全粉质量计)时对板栗粉面团质构特性、流变特性、糊化特性等的影响,并从游离巯基含量的变化加以解释,最后通过扫描电子显微镜观察板栗面团的微观结构。结果表明:TG的添加可以增强板栗面团的黏度、硬度、弹性、咀嚼性和回复性,与空白对照相比,添加量为2.7 U/g时,其最终黏度增加6.8 cP、硬度增加7.55 g、弹性增加0.38、咀嚼性增加33.62 g、回复性增加0.118,板栗面团内部的结构更加稳定;随着TG添加量的增加,板栗面团的弹性模量和黏性模量均增加,综合黏弹性上升,抗外界形变能力增强,面团稳定性及加工性能随之提高;板栗面团游离巯基的含量随TG添加量的增加而减少,添加量为2.7 U/g与未添加时的相比,游离巯基含量减少了0.16 mmol/g。但TG添加量过多会导致蛋白过度交联,淀粉粒被迫外露,面团整体的稳定性降低。综上,当TG添加量为2.7 U/g时,改善板栗面团的理化特性效果达到最佳。

谷氨酰胺治疗服用阿司匹林患者小肠黏膜损伤的随机对照研究

目的探讨谷氨酰胺对正在服用阿司匹林患者相关小肠黏膜损伤的治疗作用。方法选取2022年1月至2024年1月于首都医科大学附属北京安贞医院就诊正在服用阿司匹林,经胶囊内镜筛查有小肠黏膜损伤的患者为研究对象,采用计算机随机序列法分为干预组和对照组,干预组继续服用阿司匹林的同时加用复方谷氨酰胺肠溶胶囊治疗,对照组仅继续服用阿司匹林,不采取其他针对阿司匹林损伤的干预治疗,治疗2个月后再次行胶囊内镜检查。采用小肠内镜5级评分标准评价2组患者小肠黏膜损伤情况,研究的主要终点是2组患者小肠黏膜损伤评分的变化。结果成功入组并完成全部临床试验的共有43例患者,其中干预组22例,对照组21例。干预组治疗后小肠黏膜损伤评分较治疗前明显减低[1.0(0.0,1.3)分比2.0(2.0,3.0)分,P<0.001],对照组治疗前后小肠黏膜损伤评分比较差异无统计学意义[2.0(2.0,2.0)分比2.0(2.0,2.0)分,P=0.317]。干预组较对照组小肠黏膜损伤评分减低更多[1.0(1.0,2.0)分比0.0(0.0,0.0)分,P<0.001]。结论谷氨酰胺可以用于正在服用阿司匹林的患者以减轻相关小肠黏膜损伤。

谷氨酰胺转运载体SLC1A5对食管鳞癌细胞恶性生物学的影响及其机制

目的探讨谷氨酰胺转运载体SLC1A5在食管鳞癌细胞系中的表达、对增殖和侵袭的影响及其作用机制。方法采用实时定量PCR及免疫印迹法检测人正常食管上皮细胞系(SHEE)和食管鳞癌细胞系(KYSE30、KYSE70、KYSE140、TE1)中SLC1A5的表达水平。在SLC1A5高表达的KYSE70细胞中采用CRISPR/Cas9方法敲除SLC1A5,采用CCK8测定和划痕实验检测对照、敲除SLC1A5和使用SLC1A5抑制剂V-9302后KYSE70细胞的增殖和迁移能力。采用GSH/GSSG试剂盒检测对照、敲除SLC1A5和使用SLC1A5抑制剂V-9302后KYSE70细胞的谷氨酰胺代谢情况。结果SLC1A5在食管癌细胞系KYSE70中高表达,与正常食管上皮中的表达有统计学差异(P<0.05)。SLC1A5敲除或被抑制的KYSE70细胞的增殖能力低于未处理细胞(P<0.05),处理组划痕的迁移面积较未处理组明显减少(P<0.05),处理组的GSH/GSSG比率较未处理组的显著降低(P<0.05)。结论SLC1A5在ESCC细胞系中表达增高,抑制SLC1A5可降低ESCC细胞的增殖迁移能力与谷氨酰胺代谢,SLC1A5可能是食管癌治疗的潜在靶点。

丙氨酰-谷氨酰胺联合微生态制剂对食管早癌ESD术后肠黏膜屏障功能的影响

目的:探究丙氨酰-谷氨酰胺联合微生态制剂对食管早癌内镜粘膜下剥离术(ESD)术后肠黏膜屏障功能的影响。方法:选取2020年3月至2022年12月入新乡医学院第一附属医院行ESD术的食管早癌病人96例,随机分为对照组(n=48)和干预组(n=48)。对照组病人予以常规术前禁食、术后基础治疗及营养支持,干预组术前第3天予开始注射丙氨酰-谷氨酰胺和口服微生态制剂(双歧杆菌四联活菌片),术后第1~7天同时予以丙氨酰-谷氨酰胺和微生态制剂。比较两组病人早期肠内营养耐受性、肠道菌群分布、肠黏膜屏障功能、营养指标、炎症因子、免疫功能及术后康复情况。结果:术后7 d,干预组病人肠道不耐受症状的发生率显著低于对照组的(14.58%vs 37.50%,P<0.05)。术后,干预组双歧杆菌、乳酸杆菌较对照组增多,大肠杆菌较对照组少,二胺氧化酶、内毒素和D-乳酸水平较对照组低,总蛋白(TP)、白蛋白(Alb)和前白蛋白(PA)水平较对照组高,白细胞介素(IL-1β、-6、-8)水平较对照组低,CD3^(+)和CD4^(+)/CD8^(+)水平较对照组高(P<0.05);干预组术后首次排气时间、排便时间及住院时间短于对照组(P<0.05)。结论:给予丙氨酰-谷氨酰胺联合微生态制剂可有效提高食管早癌病人术后早期肠内营养耐受性,减轻肠黏膜屏障功能损伤,改善营养状况,提升免疫力。

联合检测CHI3L1、AFP和GGT在乙肝相关肝癌患者中的相关性研究

目的探讨血清壳多糖酶3样蛋白1(chitinase-3-like protein 1,CHI3L1)、甲胎蛋白(alpha fetoprotein,AFP)和γ-谷氨酰转移酶(γ-glutamyl transferase,GGT)检测在乙型肝炎病毒(hepatitis B virus,HBV)感染相关肝癌诊断中的临床应用价值。方法选取2021年7月—2023年7月在玉林市第一人民医院就诊HBV病毒感染相关的50例肝癌患者,50例肝硬化患者,50例慢性乙型肝炎患者以及50名同期健康体检者作为研究对象。比较4组研究对象血清中CHI3L1、AFP、GGT、丙氨酸氨基转移酶(alanine aminotransferase,ALT)、天门冬氨酸氨基转移酶(aspartate aminotransferase,AST)等水平的差异,用受试者工作特征(receiver operating characteristic curve,ROC)曲线评估各指标在肝癌中的诊断价值。结果肝炎组、肝硬化组、肝癌组的CHI3L1、AST、ALT水平均高于对照组,肝癌组AFP、GGT水平高于对照组,差异有统计学意义(P<0.05)。与肝炎组比较,肝硬化组及肝癌组的CHI3L1、AFP、GGT、AST、ALT水平均升高,差异有统计学意义(P<0.05)。与肝硬化组比较,肝癌组的CHI3L1、AFP、GGT、AST水平均升高,差异有统计学意义(P<0.05)。ROC曲线分析显示,CHI3L1、AFP、GGT联合时的曲线下面积(area under the curve,AUC)最大(AUC=0.936)。Spearman相关分析结果显示,CHI3L1与AST呈正相关(r=0.414,P=0.003),AFP与GGT呈正相关(r=0.437,P=0.002),AFP与AST呈正相关(r=0.504,P<0.001),GGT与AST呈正相关(r=0.759,P<0.001),GGT与ALT呈正相关(r=0.636,P<0.001)。结论CHI3L1、AFP及GGT联合检测可提高肝癌的诊断价值,对临床肝癌患者诊疗有重要作用。

GLN缓解中华鳖免疫应激反应机制的初步研究

本文探讨GLN缓解中华鳖(Trionyx sinensis)免疫应激反应的作用机制,为通过营养调控手段增强机体免疫保护作用,促进水生动物健康养殖提供依据。试验选择体重接近的健康中华鳖60只,随机分为3组,分别腹腔注射0.7%NaC l、500μg LPS/Kg BW、500μg LPS+100mg GLN/Kg BW。检测不同时段血浆COR、TNF-α、IL-1β、IL-6、IgM、IgG、IgA、LSZ、GSH、GSH-PX、MDA以及肝脏PRO、GSH、GSH-PX、MDA含量的变化。结果表明:注射LPS引起中华鳖产生了免疫应激反应,血浆中COR、TNF-α、IL-1β、IL-6、IgM、GSH-PX、MDA和肝脏组织PRO、GSH-PX、MDA含量在相应时段显著升高(p<0.05),而血浆和肝脏GSH含量显著降低(p<0.05);补充GLN不仅缓解了COR、TNF-α、IL-1β和IL-6等的上升趋势,而且使非特异性免疫抑制剂(MDA)水平降低。LPS作为免疫原可引起中华鳖产生免疫应激反应,补充GLN可以缓解免疫应激,对中华鳖具有免疫保护作用。

控制酶解玉米黄粉蛋白制备富含“条件必需氨基酸”——谷氨酰胺(Gln)活性肽营养液的研究(I)玉米黄粉蛋白水解用酶的筛选研究

研究了醇水体系中酶法水解玉米黄粉蛋白提取Gln活性肽的可行性 ,在 50 %乙醇 (或异丙醇 )水溶液中 ,2h内所筛选酶的活性消失 ,并且 2h内对玉米黄粉蛋白的水解度 (DH)仅有 3 %左右 ,醇浓度越高 ,活性降低越快 ,显然 ,除非对酶进行特殊的固定化处理 ,醇水体系中水解黄粉蛋白是不合适的。文章进而用水解度(DH)、氮溶解指数 (NSI)及Gln得率为指标 ,详细研究了水相中蛋白酶的水解情况 ,结果表明 ,多数酶对酰胺基具有水解作用 ,以中性蛋白酶为最 ,反应 6h ,脱酰胺率高达 4 0 .85% ,碱性蛋白酶和木瓜酶次之 ,复合酶A、风味酶和胃蛋白酶对酰胺基的水解作用较弱。

脓毒血症患者全身免疫的特点及连续性血液滤过补充Gln对改善其免疫功能的影响

目的总结脓毒血症患者全身免疫的特点,探究应用连续性血液滤过补充谷氨酰胺(Gln)对改善其免疫功能的临床价值。方法选取2017年3月至2019年3月在浦东新区人民医院急诊与重症医学科接受治疗的60例脓毒血症患者作为脓毒血症组,以同期体检健康者100例作为健康组,比较两组受检者的炎症指标和免疫指标的差异。将脓毒血症组患者根据治疗方式分为两组,其中应用连续性血液滤过补充Gln治疗的32例患者设为观察组,仅行连续血液透析治疗的28例患者设为对照组,比较两组患者的治疗效果和治疗前后的炎症因子及免疫功能改善情况。结果与健康组比较,脓毒血症组患者的C反应蛋白(CRP)、降钙素原(PCT)、白介素-2(IL-2)、IL-6、IL-8、IL-10、肿瘤坏死因子α(TNF-α)、肉毒素等炎症因子水平均明显升高,分化簇3(CD3^+)、CD4^+、CD4^+/CD8^+、人白细胞DR抗原(HLA-DR)等免疫指标水平明显降低,差异均有统计学意义(P<0.05);治疗前观察组与对照组患者的以上各项指标比较差异均无统计学意义(P>0.05);治疗后两组患者的免疫功能均明显改善,但观察组优于对照组,差异均有统计学意义(P<0.05);观察组患者的急性生理与慢性健康评分(APACHE-Ⅱ)及临床病死率分别为(11.31±2.25)分和12.50%,明显低于对照组的(16.58±3.72)分和28.57%,差异均有统计学意义(P<0.05)。结论脓毒血症患者处于严重的全身炎症反应状态,机体免疫相关指标显著升高;应用连续性血液滤过补充Gln可有效降低其全身炎症反应,改善免疫功能,临床应用价值较高。

“条件必需氨基酸——Gln”生理功能的研究进展及应用现状

Gln是一种“条件必需氨基酸” ,本文详细论述了Gln的研究背景 ,Gln的生理功能包括在免疫活性细胞、骨骼肌、胃肠道、肾脏、肝脏和大脑中的作用 。

冠心病患者对氧磷酶基因192位Gln-Arg多态性的研究

目的 探讨冠心病 (CHD)患者血脂改变是否与对氧磷酶 (PON)基因 192位 Gln- Arg变异有关。方法 应用多聚酶链反应 (PCR)对成都地区汉族 118例冠心病患者及 12 8例正常对照者 PON基因酶切位点的限制性片段长度多态性 (RFL P)进行研究。血脂用酶法测定。结果 CHD患者和正常对照组 PON基因均以 QR基因型为主 ,其频率分别为 0 .5 78和 0 .5 2 5。正常对照组和 CHD组 PON基因 R等位基因频率分别为 0 .5 2和 0 .5 0 ,无显著差异 (P>0 .0 5 )。中国人 PON基因 R等位基因频率显著高于白种人及印度人 (P<0 .0 1) ,而低于日本人及中国台北人(P<0 .0 1) ,存在种族差异。结论 未发现 PON1基因 192位 Gln- Arg多态性与中国人