High Level Expression of Glucose-6-phosphate Dehydrogenase Gene PsG6PDH from Populus suaveolens in E. coli

In order to investigate the functions of the gene PsG6PDH and the mechanisms underlying freezing tolerance of Populus suaveolens, the recombinant expression vector pET-G （pET30a-G6PDH）, which contained full encoding region of PsG6PDH gene, was established. The recombinant was identified by lawn-PCR and double enzyme digestion and then transformed into expression host XA90 and induced by isopropyl-a-D-thiogalactoside （IPTG） to express 100 kD polypeptide of G6PDH fusion protein. The results showed that the expressed amount of the fusion protein culminated after 1 mmol·L^-1 IPTG treatment for 4h and that pET-G product was predominately soluble and not extra-cellular secreting.

Cloning and Sequence Analysis of a Glucose-6-Phosphate Dehydrogenase Gene PsG6PDH from Freezing-tolerant Populus suaveolens

A 1 207 bp cDNA fragment (PsG6PDH) was amplified by RT-PCR from cold-induced total RNA of the freez- ing-tolerant P. Suaveolens, using primers based on the highly conserved region of published plant glucose-6-phosphate dehydro- genase (G6PDH) genes. The sequence analysis showed that PsG6PDH coding region had 1 101 bp and encoded 367 predicted amino acid residues. Moreover, the nucleotide sequence of PsG6PDH showed 83%, 82%, 79%, 79% and 78% identity, and the derived amino acid sequence shared 44.2%, 44.7%, 42.0%, 40.5% and 43.9% identity with those of the Solanum tuberosum, Nicotiana ta- bacum, Triticum aestivum, Oryza sativa and Arabidopsis thaliana, respectively. The results show that PsG6PDH is a new member of G6PDH gene family and belongs to the cytosolic G6PDH gene. This is the first report on cloning of the G6PDH gene from woody plants.

Is glucose-6-phosphate dehydrogenase deficiency more prevalent in Carrion's disease endemic areas in Latin America?

Glucose-6-phosphate dehydrogenase(G6PD) is a cytoplasmic enzyme with an important function in cell oxidative damage prevention.Erythrocytes have a predisposition towards oxidized environments due to their lack of mitochondria,giving G6 PD a major role in its stability.G6 PD deficiency(G6PDd) is the most common enzyme deficiency in humans:it affects approximately 400 million individuals worldwide.The overall G6 PDd allele frequency across malaria endemic countries is estimated to be 8%.corresponding to approximately 220 million males and 133 million females.However,there are no reports on the prevalence of G6 PDd in Andean communities where bartonellosis is prevalent.

Prevalence of Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency in India: A Systematic Review

Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is the most common enzyme deficiency of human erythrocyte affecting more than 400 million people worldwide. In India, G6PD deficiency was first reported in 1963 and since then various investigations have been conducted across country. The objective of this work was to study the prevalence of G6PD deficiency in different ethnic, caste and linguistic groups of Indian population. A systematic search of published literature was undertaken and the wide variability of G6PD deficiency has been observed ranging from 0% - 30.7% among the different caste, ethnic, and linguistic groups of India. It was observed that the incidence of G6PD deficiency was found to be considerably higher among the tribes (9.86%) as compared to other ethnic groups (7.34%) and significantly higher in males as compared to females.

Purification and Characterization of Glucose-6-Phosphate Dehydrogenase from Pigeon Pea (Cajanus cajan) Seeds

Glucose-6-phosphate dehydrogenase has been purified from pigeon pea (Cajanus cajan) seeds and subjected to characterization. The enzyme was purified 123.69 fold with a yield of 21.37% by ammonium sulphate fractionation, PEG-4000 precipitation, CM cellulose column chromatography and DEAE cellulose column chromatography. The catalytically active enzyme is a dimer of 113 KDa with a subunit molecular weight of 55 KDa. Thermal inactivation of enzyme follows first order kinetics at 30&#176C and 40&#176C with half life of 6 and 1.5 min respectively. Km value for glucose-6-phosphate and NADP+ was found to be 2.68 mM and 0.75 mM respectively whereas Vmax value was found to be 0.11 U/mL and 0.13 U/mL respectively. The enzyme shows more affinity towards NADP+ than glucose-6-phosphate. The pKa value was found to be 10.41 indicating that the amino acid residue at active site might be lysine. The enzyme exhibited maximum catalytic activity at pH 8.2. The enzyme was found to be highly thermosensitive with gradual loss of activity above 30&#176C temperature.

Biochemical Estimation of Glucose 6 Phosphate Dehydrogenase Deficiency in Saudi Adults: Different Methods and Its Rationalization

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy affecting 400 million people, globally. G6PD deficiency is an X-linked genetic condition, which is more likely to affect males than females. Heterozygous females go undetected in a commonly used method. The aim of the study was to identify & rationalize different biochemical methods for detections of G6PD deficiency. Methods: Cross section retrospective study was conducted on 1584 (800 males, 784 females) blood samples collected from King Abdulaziz University Hospital (KAUH) and King Fahd Armed force hospital (KFAFH) in Jeddah, Western Saudi Arabia. Blood samples were screened for G6PD activity by fluorescence spot test, semi quantitative color reduction test and spectrometric quantitative evaluation. Hemoglobin (Hb) was measured on the same sample by BC-3200 Auto hematology Analyser. G6PD activity was recorded as U/g Hb. Samples identified as deficient with cutoff ≤4.6 U/gHb. Results: The prevalence of G6PD deficiency identified by fluorescence spot test was 73(4.6%) and all were deficient male. By semi quantitative method, the prevalence rate was 51(3.2%) and again all were male deficit patients. However, when quantitative spectrometric method was used, the prevalence was found in 90(5.7%), where in 73(4.6%) deficient patients were males and 17(1.1%) were females. Conclusion: Since the fluorescence spot test did not miss any G6PD deficient male, it should be restricted to males and quantitative test should be done on females. Each ethnic group should cultivate their own cutoff value for categorization of deficient patients.

Glucose-6-phosphate dehydrogenase(G6PD) deficiency is associated with asymptomatic malaria in a rural community in Burkina Faso

Objective:To investigate 4 combinations of mutations responsible for glucose-6—phosphate dehydrogenase(G6PD) deficiency in a rural community of Burkina Faso,a malaria endemic country.Methods:Two hundred individuals in a rural community were genotyped for the mutations A376 G.G202A,A542 T,G680T and T968 C using TaqMan single nucleotide polymorphism assays and polymerase chain reaction followed by restriction fragment length polymorphism.Results:The prevalence of the G6 PD deficiency was 9.5%,in the study population.It was significantly higher in men compared to women(14.23%vs 6.0%,P=0.049).The 202A/376 G G6PD Awas the only deficient variant detected.Plasmodium falciparum asymptomatic parasitemia was significantly higher among the C6PD-non—deficient persons compared to the G6PD-deficient(P<0.001).The asymptomatic parasitemia was also significantly higher among G(SPI) nondeficient compared to C6PD—heterozygous females(P<0.001).Conclusions:This study showed that the G6 PD A- variant associated with protection against asymptomatic malaria in Burkina Faso is probably the most common deficient variant.

Is there any role of glucose-6-phosphate dehydrogenase in obesity induced metabolic disorder

The present study was designed to explore the possible mechanism of obesity associated metabolic syndrome. 150 subjects (120 men and 30 women) in the age-group of 17 - 26 years were studied. Body Mass Index and Waist-to-Hip Ratio were taken as a measure of generalized obesity and abdominal adiposity. The serum concentration of glucose-6-phosphate dehydrogenase increased with increasing levels of Body Mass Index and was found to be significant in obese subjects (Body Mass Index ≥ 30.0 kg/m2) and more so in the obese subjects with abdominal adiposity (p = 0.002) as compared to normal-weight subjects. Karl Pearson coefficient of correlation revealed a significant positive correlation of glucose-6-phosphate dehydrogenase with Body Mass Index (r = 0.499;p < 0.001) and malondialdehyde (a biomarker of oxidative stress) (r = 0.736;p < 0.001) but inverse correlation with adiponectin (r = -0.524;p < 0.001). Thus, we conclude that increased expression of glucose-6-phosphate dehydrogenase in obese subjects (more if it is associated with abdominal adiposity) might mediate the onset of obesity associated metabolic disorders by increasing oxidative stress.

Cloning and characterization of a glucose 6-phosphate／phosphate translocator from Oryza sativa

Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 phosphate/phosphate translocator ( GPT ) was isolated from a cDNA library of immature seeds of rice and named as OsGPT . The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000 grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6 phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.

The diagnostic significance of glucose-6-phosphate isomerase (G6PI) antigen and anti-G6PI antibody in rheumatoid arthritis patients

Objective: To investigate whether glucose-6-phosphate isomerase (G6PI) antigen and anti-G6PI antibodies could be applied for the clinical diagnostic markers of rheumatoid arthritis (RA) and its associations with RA activity states. Methods: The levels of G6PI antigens and anti-G6PI Abs in sera from 176 RA patients in different states, 35 non-RA patients and 100 healthy donors and in synovia fluids from 33 patients and 11 non-RA patients were measured by ELISA. Results: The sensitivity and specificity of G6PI antigens in the RA patients were 75.0% and 93.3%, respectively. The levels of serum G6PI antigens in 176 RA patients were significantly higher than non-RA patients and the health controls. Especially, there was a significant difference between the active phase and the inactive phase in G6PI antigens levels. The levels of G6PI antigens in synovia fluid were also significantly higher in RA groups than in non-RA patients. With the values of the anti-G6PI Abs in sera, there were no marked differences among RA, non-RA patients and health controls. Also, there was no significant difference between the active phase and the inactive phase in RA patients. However, there were no significant differences of G6PI and anti-G6PI between RA patients and health controls in synovial fluid. Conclusions: G6PI is highly correlated with the activity states of RA, and could be applied for a clinical biomarker with high sensitivity and specificity for the diagnosis of RA.

Characterization of glucose-6-phosphate dehydrogenase deficiency and identification of a novel haplotype 487G>A/IVS5-612(G>C) in the Achang population of southwestern China

The prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency and its gene mutations were studied in the Achang population from Lianghe County in Southwestern China. We found that 7.31% (19 of 260) males and 4.35% (10 of 230) females had G6PD deficiency. The molecular analysis of G6PD gene exons 2―13 was performed by a PCR-DHPLC-Sequencing or PCR-Sequencing. Sixteen inde-pendent subjects with G6PD Mahidol (487G>A) and the new polymorphism IVS5-612 (G>C), which combined into a novel haplotype, were identified accounting for 84.2% (16/19). And 100% Achang G6PD Mahidol were linked to the IVS5-612 C. The percentage of G6PD Mahidol in the Achang group is close to that in the Myanmar population (91.3% 73/80), which implies that there are some gene flows between Achang and Myanmar populations. Interestingly, G6PD Canton (1376G>T) and G6PD Kaiping (1388G>A), which were the most common G6PD variants from other ethnic groups in China, were not found in this Achang group, suggesting that there are different G6PD mutation profiles in the Achang group and other ethnic groups in China. Our findings appear to be the first documented report on the G6PD genetics of the AChang people, which will provide important clues to the Achang ethnic group origin and will help prevention and treatment of malaria in this area.

A diagnostic kit to screen individuals with glucose-6-phosphate dehydrogenase defect and its application on anti-malaria spot in the countryside

Objective To prepare a kit for screening individuals with glucose 6 phosphate dehydrogenase (G6PD) defect. The kit is easy to use and to get the fast as well as reliable results. Especially it is suitable for the anti malaria spots usually located in the remote countryside where no electricity is available. Methods The double filter paper method and other 2 techniques, the quantitative method and the single filter paper method, were used to determine G6PD activity in 70 samples of human erythrocytes. It was found that the results of the double filter paper method and those of the single filter paper method in the first 8 hours after the drying of the blood soaked filter paper were consistent with those of the quantitative method. When a piece of blood soaked paper is left under room temperature more than 24 hours, G6PD in the erythrocytes deteriorated spontaneously and consequently the number of positive cases increased along with the elapse of time.Results Satisfactory results were achieved when the kit was used to screen cases of G6PD defect from 151 farmers who were receiving anti mararia therapy. The kit was made according to a technique named “double filter paper” method.Conclusions These findings suggest that the double filter paper method can reveal the level of G6PD activity and the results are rapidly obtained when the method is used on the anti malaria spot.

Alleviation of PEGylated Puerarin on Erythrocyte Hemolysis Induced by Puerarin in Glucose-6-phosphate Dehydrogenase-deficient Rats

Objective To explore and analyze the reducing hemolytic effects of PEGylated puerarin (PEG-PUE) on erythrocytes induced by PUE in glucose-6-phosphate dehydrogenase (G6PD)-deficient rats. Methods The rat model with G6PD-deficiency was established via sc injecting 1% acetylphenyl-hydrazine. Then the G6PD-deficient erythrocyte suspension obtained from this rat model was used to evaluate the hemolytic effects of PUE and the reducing hemolytic effects of PEG-PUE via hemolytic activity and erythrocyte osmotic fragility assay. Results It was found that PUE could cause a serious hemolysis to the erythrocyte suspension with the increase of drug concentration and the prolongation of drug incubation time, the hemolytic rate of PUE was up to 40%, while the addition of PEG-PUE to the erythrocyte suspension revealed no significant hemolysis. Additionally, the result of erythrocyte osmotic fragility indicated that PEG-PUE exerted a slight effect on the erythrocyte membranes, and the NaCl concentration that induced 50% hemolysis (32 mmol/L) was about one-third PUE. Conclusion These results demonstrate that PEG-PUE could play a significant role in reducing the side effect of hemolysis induced by PUE. The low hemolytic activity of PEG-PUE makes it a favorable candidate for in vivo tests and PEG-PUE could also provide the useful insight for the further formulation development as an innovative drug.

CDFI血流信号分级、抗CCP抗体、G6PI、RF对类风湿性关节炎的诊断价值

目的分析彩色多普勒血流显像(CDFI)血流信号分级、抗环瓜氨酸肽抗体(CCP)、葡萄糖6磷酸异构酶(G6PI)、类风湿因子(RF)对类风湿性关节炎(RA)的诊断价值。方法回顾性选取2022年4月至2023年10月新疆医科大学附属中医医院收治的100例RA患者纳入观察组,根据病情分为RA活动期组(n=50)和RA非活动期组(n=50);依据血流信号CDFI分级分为0~1级组(n=20)、2级组(n=17)、3级组(n=13)。选取同期本院收治的100例其他自身免疫性疾病患者纳入对照组。比较观察组、对照组一般临床资料(性别、病程、年龄、RA家族史、体重指数、吸烟史、饮酒史、居住地、职业等),比较不同活动期患者抗CCP抗体、G6PI及RF水平;比较不同血流信号分级组患者抗CCP抗体、G6PI及RF水平;采用受试者工作特征(ROC)曲线评估CDFI血流信号分级、抗CCP抗体、G6PI、RF联合检测对RA的诊断价值。结果两组患者性别构成比、病程、年龄、RA家族史、体重指数、吸烟史、饮酒史、居住地、职业比较,差异均无统计学意义(P>0.05);观察组患者抗CCP抗体、G6PI及RF水平均高于对照组,差异均有统计学意义(P<0.05)。RA活动期组患者抗CCP抗体、G6PI及RF水平均高于RA非活动期组患者,差异均有统计学意义(P<0.05)。血流信号3级组患者抗CCP抗体、G6PI及RF水平均高于血流信号0-1级组、2级组患者,差异均有统计学意义(P<0.05)。CDFI血流信号分级、抗CCP抗体、G6PI、RF单独检测RA的敏感度分别为79.57%、86.45%、82.14%、77.89%,特异度分别为83.89%、79.28%、83.67%、84.15%,AUC分别为0.855(0.804~0.907)、0.940(905~0.976)、0.893(0.852~0.935)、0.800(0.736~0.864),CDFI血流信号分级、抗CCP抗体、G6PI、RF联合检测RA的敏感度为89.36%,特异度为77.24%,AUC为0.957(0.933~0.980)。结论RA患者血清CCP抗体、G6PI、RF水平升高,随着CDFI血流信号分级增大,升高愈加明显,CDFI血流信号分级、抗CCP抗体、G6PI、RF联合检测RA诊断价值较高,对判断RA进展具有意义。

肇庆市68308名新生儿葡萄糖-6-磷酸脱氢酶缺乏症筛查结果综合分析

目的:分析肇庆市68308名新生儿的葡萄糖-6-磷酸脱氢酶(G6PD)缺乏症筛查结果。方法:选取2021年1月—2022年12月在肇庆市出生的68308名新生儿为研究对象,采集全部新生儿的足跟血,以荧光分析法对G6PD缺乏症进行初筛,对可疑阳性者召回,采集静脉血以连续监测法进行确诊。结果:2021年共筛查35610名,初筛阳性3580名,占比10.05%(3580/35610);2022年共筛查32698名,初筛阳性2983名,占比9.12%(2983/32698);6563例初筛阳性者,进行确诊检查,其中2021年确诊2585例,2022年确诊2153例,共确诊4738例G6PD缺乏症,确诊率为6.94%(4738/68308)。6563例初筛阳性者中,男5186例,女1377例;男婴初筛阳性中,共确诊3829例,确诊率为5.61%(3829/68308),女婴初筛阳性者中,共确诊909例,确诊率为1.33%(909/68308),男婴初筛阳性确诊率高于女婴初筛阳性确诊率,差异有统计学意义(χ^(2)=33.148,P<0.05);4738例G6PD缺乏症中,重度缺乏1130例,占比23.85%(1130/4738),中度缺乏1067例,占比22.52%(1067/4738),轻度缺乏2541例,占比53.63%(2541/4738)。结论:肇庆市68308名新生儿中,G6PD缺乏症以男婴为主,病情多为轻度缺乏。

LncRNA LBX2-AS1调节miR-873-5p/G6PD轴对胃癌细胞增殖迁移和侵袭的影响

目的:探讨长链非编码RNA(LncRNA)瓢虫同源盒2反义RNA1(LBX2-AS1)调节微小RNA-873-5p(miR-873-5p)/葡萄糖-6-磷酸脱氢酶(G6PD)轴对胃癌(GC)细胞增殖、迁移和侵袭的影响。方法:以SGC7901细胞为研究对象,将其随机分为Control组、sh-NC组、sh-LBX2-AS1组、sh-LBX2-AS1+inhibitor-NC组、sh-LBX2-AS1+miR-873-5p inhibitor组;qRT-PCR法检测LncRNA LBX2-AS1、miR-873-5p、G6PD的表达;MTT法和平板克隆实验检测SGC7901细胞增殖;划痕实验检测SGC7901细胞迁移;Transwell实验检测SGC7901细胞的侵袭;Western blot检测SGC7901细胞中MMP-2、PCNA、MMP-9、G6PD蛋白表达;荧光素酶报告基因实验检测LncRNA LBX2-AS1与miR-873-5p,miR-873-5p与G6PD之间的相互作用;小鼠荷瘤实验验证敲除LncRNALBX2-AS1对CC肿瘤生长及G6PD表达的影响。结果:sh-LBX2-AS1组SGC7901细胞中A490值、克隆数、划痕愈合率、侵袭数、LncRNA LBX2-AS1、G6PD mRNA和PCNA、MMP-2、MMP-9蛋白表达低于sh-NC组、Control组,miR-873-5p表达高于sh-NC组、Control组(P<0.05);与sh-LBX2-AS1组、sh-LBX2-AS1+inhibitor-NC组相比,sh-LBX2-AS+miR-873-5p inhibitor组miR-873-5p表达降低,A490值、克隆数、划痕愈合率、侵袭数、G6PD mRNA和PCNA、MMP-2、MMP-9蛋白表达升高(P<0.05)。LncRNA LBX2-AS1靶向负调控miR-873-5p,miR-873-5p靶向负调控G6PD。实验组移植瘤质量、体积、Ki-67阳性率、G6PD阳性率低于对照组(P<0.05)。结论:敲除LncRNA LBX2-AS1可能抑制GC细胞的增殖、迁移和侵袭,其机制可能是调节miR-873-5p/G6PD轴实现的。

Glucose 6 phosphatase dehydrogenase (G6PD) and neurodegenerative disorders:Mapping diagnostic and therapeutic opportunities

Glucose 6 phosphate dehydrogenase(G6PD)is a key and rate limiting enzyme in the pentose phosphate pathway(PPP).The physiological significance of enzyme is providing reduced energy to specific cells like erythrocyte by maintaining co-enzyme nicotinamide adenine dinucleotide phosphate(NADPH).There are preponderance research findings that demonstrate the enzyme(G6PD)role in the energy balance,and it is associated with bloodrelated diseases and disorders,primarily the anemia resulted from G6PD deficiency.The Xlinked genetic deficiency of G6PD and associated non-immune hemolytic anemia have been studied widely across the globe.Recent advancement in biology,more precisely neuroscience has revealed that G6PD is centrally involved in many neurological and neurodegenerative disorders.The neuroprotective role of the enzyme(G6PD)has also been established,as well as the potential of G6PD in oxidative damage and the Reactive Oxygen Species(ROS)produced in cerebral ischemia.Though G6PD deficiency remains a global health issue,however,a paradigm shift in research focusing the potential of the enzyme in neurological and neurodegenerative disorders will surely open a new avenue in diagnostics and enzyme therapeutics.Here,in this study,more emphasis was made on exploring the role of G6PD in neurological and inflammatory disorders as well as non-immune hemolytic anemia,thus providing diagnostic and therapeutic opportunities.

Mineral phosphate solubilization activity of gluconacetobacter diazotrophicus under P-limitation and plant root environment

The ability to solubilize insoluble inorganic pho- sphate compounds by Gluconacetobacter diazotrophicus was studied using different cul-ture approaches. Qualitative plate assays using tricalcium phosphate as the sole P-source showed that G. diazotrophicus produced solu-bilization only when aldoses were used as the C-source. Extracellular aldose oxidation via a pyrroloquinoline quinone-linked glucose dehy-drogenase (PQQ-GDH) is the main pathway for glucose metabolism in G. diazotrophicus. In batch cultures with 5 g l-1 of hydroxyapatite as the P-source and glucose as the C-source, more than 98% of insoluble P was solubilized. No solubilization was observed neither using glyc-erol nor culturing a PQQ-GDH mutant of G. di-azotrophicus. Solubilizaton was not affected by adding 100 mmol l-1 of MES buffer. Continuous cultures of G. diazotrophicus showed significant activities of PQQ-GDH either under C or P limi-tation. An intense acidification in the root envi-ronment of tomato and wheat seedlings inocu-lated with a G. diazotrophicus PAL5 was ob-served. Seedlings inoculated with a PQQ-GDH mutant strain of G. diazotrophicus showed no acidification. Our results suggest that G. di-azotrophicus is an excellent candidate to be used as biofertilizer because in addition to the already described plant growth-promoting abili-ties of this organism, it shows a significant mineral phosphate solubilization capacity.

Comparisons of different methods of anesthesia and analgesia on the levels of glycometabolism rate-limiting enzymes in erythrocytes and plasma glucose and stress hormones in patients undergoing esophagus surgery

Objective： To compare the effects of different methods of anesthesia and analgesia on the activities of phosphofructokinase（PFK）, glucose-6-phosphate dehydrogenase（G-6PD） and aldose reductase（AR） in erythrocytes and levels of plasma glucose and stress hormones in patients undergoing esophagus surgery. Methods： Sixty-two patients scheduled for esophagus surgery were randomly divided into three groups： group Ⅰ （n = 20） receiving only general anesthesia（GA） followed by intravenous patient controlled analgesia（PCA） with fentanyl 15 μg/kg. The other two groups receiving both general anesthesia combined with thoracic epidural anesthesia （GEA） and either intravenous PCA with fentanyl 15 μg/kg （group Ⅱ, n = 21） or thoracic epidural analgesia（TEA） with 0.125% ropivacaine and 0.0002% fentanyl mixture（group Ⅲ, n = 21） after the operation. Venous blood samples were collected for measurements of PFK, G-rPD and AR activities in erythrocytes and plasma glucose, cortisol, epinephrine and norepinephrine before induction （T1）, 60 min following the incision （T2）, 60 min（T3） after operation, on the lst（T4） and 2nd postoperative day（T5）. Results： The activities of PFK decreased（P 〈 0.01 or P = 0.004） and the activities of G-6PD and AR increased（P 〈 0.01） in groups Ⅰ and Ⅱ on T4 compared with those on T1 Between the two groups, the activities of these enzymes in group Ⅱ changed less than those of group Ⅰ （P 〈 0.01 or P 〈 0.05）. These enzymes activities changed slightly in group Ⅲ on T4（P 〉 0.05）. There were significant differences between group Ⅲand the other two groups（P 〈 0.0l or P 〈 0.05）. The levels of plasma glucose increased significantly on T2（P 〈 0.01）, reached peak values on Ta（P 〈 0.01） and fell on T5 in the three groups. Compared to those of groups Ⅰ and Ⅱ, the values of plasma glucose in group Ⅲwere lower on T4 and T5（P 〈 0.05 or P 〈 0.01）. The cortisol concentration in each group increased significantly at T2（P 〈 0.01 or P 〈 0.05）, and remained elevated on T5（P 〈 0.01 or P 〈 0.05）, while on T2 and T3 the cortisol levels＇ of group I were higher than that of groups Ⅱand Ⅲ （P 〈 0.05）. The levels of group Ⅲ were lower than those of the other groups on T4 and T5（P 〈 0.01 or P 〈 0.05）. The levels of epinephrine and norepinephrine were also significantly higher in group Ⅰ than those of the other two groups on T2（P 〈 0.01 or P 〈 0.05）, and their levels in group Ⅰ and Ⅱ were higher than that of group Ⅲ on T4. The patients of the three groups obtained satisfactory pain relief, with all Vidual Analogue Scale（VAS） scores less than 3. VAS scores of group I were much greater 4h after operation. Group m VAS scores were the lowest 24h after operation. However, the number of times patients pressed the bolus switch was higher in group Ⅱ （P 〈 0.01）. Conclusion： Compared with GA and intravenous PCA, general anesthesia combined with thoracic epidural anesthesia and analgesia obtain better pain relief and could markedly alleviate the stress response and improve these erythrocyte glucose metabolism changes after esophagus surgery.

Phosphoglucose Isomerase Deficiency in <i>Escherichia coli</i>K-12 Is Associated with Increased Spontaneous Mutation Rate

Phosphoglucose isomerase (PGI) is a key enzyme in early glycolysis, which catalyzes the reversible isomerization of glucose 6-phosphate (G6Ph) to fructose 6-phosphate. We have constructed an Escherichia coli K12 strain with a deleted pgi gene (Δpgi) and shown that this strain in comparison with the parental strain 1) accumulates higher amount of G6Ph, 2) grows slowly, and 3) exhibits higher spontaneous mutation frequency to rifampicin resistance (Rifr), when grown on high glucose minimal medium. Intriguingly, the spontaneous mutation rate to Rifr was inversely related to the degree of E. coli chromosomal DNA modification with sugar derivatives. We measured higher concentrations of Amadori products, fluorophores (360 nm excitation/440 nm emission) and carboxymethyl residues in the chromosomal DNA of the E. coli parental strain than in DNA of the isogenic Δpgi strain. To explain this apparent paradox we hypothesized that PGI might be implicated in repair of G6Ph-derived lesions in DNA. In favor of our hypothesis, we further demonstrate that protein extract from the E. coli PGI proficient strain but not from the PGI deficient strain catalyzes the release of G6Ph from G6Ph-modified single stranded DNA oligonucleotide and from its hybrid duplex with a complementary peptide nucleic acid.