AIM： To assess the prevalence and socio-demographic distribution of hepatitis B virus （HBV） infection in Albania. METHODS： Blood samples from 410 unselected schoolboys, 666 students, 500 military personnel, 1286 c...AIM： To assess the prevalence and socio-demographic distribution of hepatitis B virus （HBV） infection in Albania. METHODS： Blood samples from 410 unselected schoolboys, 666 students, 500 military personnel, 1286 casual blood donors, 378 voluntary blood donors and 640 pregnant women （total 3880 non-vaccinated residents of rural and metropolitan areas from all over Albania; 2354 （60.7%） male and 1526 （39.3%） female; mean age of 26.3 years） were tested during 2004-2006 for hepatitis B surface antigen （HBsAg） and antibodies to hepatitis B virus （anti-HBs） by ELISA. RESULTS： The HBsAg and anti-HBs prevalence were 9.5% and 28.7%, respectively. The highest HI3sAg prevalence was evident in the younger age group, such as in schoolchildren （11.8%） and the military （10.6%）. Consequently, the anti-HBs prevalence increased with age, from 21.2% in schoolchildren （mean age： 15.7 years）, to 36.3% in pregnant women （mean age： 26.3 years） and 29.7% in voluntary blood donors （mean age： 40.1 years）. There were no significant differences between males and females. CONCLUSION： Despite the estimated two-fold reduction of HBsAg prevalence in the general population from about 18%-19% to 9.5%, Albania remains a highly endemic country （i.e. over 8% of HBsAg prevalence rate）.展开更多
Gelatinase A (MMP-2) is considered to play a critical role in cell migration and invasion. The proteinase is secreted from the cell as an inactive zymogen. In vivo it is postulated that activation of progelationase A ...Gelatinase A (MMP-2) is considered to play a critical role in cell migration and invasion. The proteinase is secreted from the cell as an inactive zymogen. In vivo it is postulated that activation of progelationase A (proMMP-2) takes place on the cell surface mediated by membrane-type matrix metalloproteinases (MT-MMPs). Recent studies have demonstrated that proMMP-2 is recruited to the cell surface by interacting with tissue inhibitor of metalloproteinases-2 (TIMP-2) bound to MT1MMP by forming a ternary complex. bee MT1-MMP closely located to the ternary complex then activates proMMP-2 on the cell surface. MT1-MMP is found in cultured invasive cancer cells at the invadopodia. The MTMMP/TIMP-2/ MMP- 2 system t bus provides localized expression of proteolysis of the extracellular matrix required for cell migration.展开更多
Complexation and interaction between silver and amino group were applied to induce an efficient immobilization of papain on silica spheres.Tbe silver nanoparticles were deposited on the silica spheres before p apainwa...Complexation and interaction between silver and amino group were applied to induce an efficient immobilization of papain on silica spheres.Tbe silver nanoparticles were deposited on the silica spheres before p apainwas coupled to the silica spheres. The silica spheres with silver nanoparticles were characterized by high resolution transmission electron microscopy （HR-TEM）, Fournier transform infrared spectroscopy （FT-IR）, and UV-Vis scanning spectrometer. FT-IR spectrum was also used to characterize the immobilized and free papain. Effect of some factors on the activities of the immobilized papain was investigated. It was observed that the coupled yield and relative activity of the papain on Ag/SiO2 were 1.17 and 1.86 times of those on the bare SiO2, respectively. At an optimum concentration of silver, theobserved activity of the immobilized papain was 2.1 timesof that on the bare.silica.In addition, the maximum specific activity of papain immobilized on Ag/SiO2 was 819.9 U·mg·^-1, which is slightly lower than that of the free papain, 906.2 U·mg^-1 . Stability of the immobilized papain was also examined. The resuits indicate that the silver nanoparticles successfully induce a fine immobilization of papain.展开更多
In order to study the effects of ionic surfactants on bacterial luciferase,the cationic surfactant dodecyltrimethylammonium biomide (DTAB) and anionic surfactant sodium dodecylsulfate (SDS) were chosen.For comparison ...In order to study the effects of ionic surfactants on bacterial luciferase,the cationic surfactant dodecyltrimethylammonium biomide (DTAB) and anionic surfactant sodium dodecylsulfate (SDS) were chosen.For comparison with bacterial luciferase,α-amylase was used since these two enzymes have similar electrostatic potential and charged active sites.After the enzymes were treated with the surfactants,the catalytic properties of bacterial luciferase andα-amylase were assayed,and fluorescence spectroscopy and circular dichroism (CD) were used to analyze the alteration of the protein structure.The results showed that when the DTAB concentration was low,the cationic surfactant DTAB enhanced the enzymatic activities of bacterial luciferase andα-amylase.On the other hand,the anionic surfactant SDS did not alter the enzymatic activity.The main interaction of cationic surfactant DTAB and the negatively charged surface of the proteins was the ionic interaction,which could alter the environment for the enzyme to work when the DTAB/enzyme molar ratio was low.However,at high cationic surfactant concentration,the ionic interaction and hydrophobic interaction might destroy the secondary and tertiary structures of the proteins,leading to the loss of enzymatic activities.展开更多
AIM： To evaluate the clinical significance of CpG island methylator phenotype （CIMP） in plasma and its association with hepatocellular carcinoma （HCC） progress. METHODS： CIMP status of 108 HCC patients was analy...AIM： To evaluate the clinical significance of CpG island methylator phenotype （CIMP） in plasma and its association with hepatocellular carcinoma （HCC） progress. METHODS： CIMP status of 108 HCC patients was analyzed using a methylation marker panel in tumor tissues and plasma with methylation-specific polymerase chain reaction. Fifteen samples of non-neoplastic liver tissues and 60 of plasma from healthy persons were examined simultaneously. Examined genes included APC, WIF-1, RUNX-3, DI C-1, SFRP-1, DKK and E-cad.26/108, 24.07% in plasma; WIF-1, 53/108, 49.07% in tissue and 35/108, 32.41% in plasma; RUNX-3, 52/108, 48.14% in tissue and 42/108, 38.89% in plasma; DIC-1, 38/108, 35.18% in tissue and 23/108, 21.30% in plasma; SFRP-1, 40/108, 37.04% in tissue and 31/108, 28.7% in plasma; DKK, 39/108, 36.1% in tis- sue and 25/108, 23.14% in plasma; and E-cad, 37/108, 34.3% in tissue and 18/108, 16.67% in plasma. CIMP＋ （≥3 methylated genes） was detected in 68 （60.2%） tumor tissue samples and 62 （57.4%） plasma samples. CIMP was not detected in non-neoplastic liver tissues or plasma of healthy persons. CIMP status in tumor tissues differed significantly in gender, hepatitis B surface antigen, alpha-fetoprotein, and tumor-node- metastasis stage （P 〈 0.05）. Similar results were obtained with plasma samples （P 〈 0.05）. There was no difference in CIMP status in age, presence of hepatitis C virus antibody, cirrhosis, number of nodes, number of tumors, tumor size, or Edmondson-Steiner stage. A one-year follow-up found that the metastatic rate and recurrence rate in the CIMP＋ group were significantly higher than in the CIMP- group as assessed with plasma samples （P 〈 0.05）. CONCLUSION： Plasma DNA can be a reliable sample source for CIMP analysis. CIMP in plasma may serve as a molecular marker of late-stage and poor-prognosis HCC.展开更多
The optimization of cultural conditions for β glucanase production by Bacillus subtilis ZJF 1A5 was investigated in flask trials. Temperature had great effect on β glucanase production which maximized...The optimization of cultural conditions for β glucanase production by Bacillus subtilis ZJF 1A5 was investigated in flask trials. Temperature had great effect on β glucanase production which maximized at optimal temperature of 37℃ and decreased significantly when temperature was over 37℃.Charge quantity affected β glucanase production significantly. Adding oxygen vector N dodecane or acetic ether benefited β glucanase production, but it depended on the concentration and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were the key factors affecting β glucanase production and the cultivation time span to reach the highest β glucanase activity. The optimal cultural conditions for β glucanase production obtained with CCD were as follows: inoculum age and size (16 h, 3.82%(v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37℃ for 50 h. Repeated experimental results accorded with those predicted by a second order polynomial model. The amount of β glucanase, α amylase and neutral protease produced by B subtilis ZJF 1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and increased significantly when cells entered the stationary phase.展开更多
The aim of this research is to study the floatation deinking abilities of black mold enzyme and chemicals in newsprint paper application. In this experiment, the properties of deinked pulp from three different additiv...The aim of this research is to study the floatation deinking abilities of black mold enzyme and chemicals in newsprint paper application. In this experiment, the properties of deinked pulp from three different additives--chemicals, black mold enzyme, and chemicals together with black mold enzyme, are studied. The first part of the experiment was to find the optimal amount of chemicals and the optimal pH through the use of sodium hydroxide and surfactant. As a result, 0.2% of sodium hydroxide and 0.4% of surfactant on oven dried weight at pH 9 was found to be the optimal condition for the deinked pulp to yield the lowest ERIC （effective residual concentration） and the highest brightness. The second part of the experiment was to find the optimal amount of black mold enzyme used in the deinking process. As a result, the optimal condition for deinked pulp to retain the lowest ERIC and the highest brightness was 100 ppm of black mold enzyme and 10 minutes of enzyme reaction time. The third part of experiment was to study the de-inking ability of black mold enzyme and chemicals. Consequently, with 30 min of chemicals reaction time and 60 min of black mold reaction time, the deinked pulp retained low ERIC but higher brightness.展开更多
Magnetic nanoparticles（Fe3O4） were synthesized by co-precipitating Fe^2＋ and Fe^3＋ ions in an ammonia solution and treating under hydrothermal conditions.Cellulase was immobilized onto Fe3O4 magnetic nanoparticles...Magnetic nanoparticles（Fe3O4） were synthesized by co-precipitating Fe^2＋ and Fe^3＋ ions in an ammonia solution and treating under hydrothermal conditions.Cellulase was immobilized onto Fe3O4 magnetic nanoparticles via glutaraldehyde activation.Using response surface methodology and Box-Behnken design,the variables such as magnetic nanoparticle concentration,glutaraldehyde concentration,enzyme concentration,and cross linking time were optimized.The Box-Behnken design analysis showed a reasonable adjustment of the quadratic model with the experimental data.Statistical contour plots were generated to evaluate the changes in the response surface and to understand the relationship between the nanoparticles and the enzyme activity.Scanning electron microscopy,X-ray diffraction analysis,and Fourier transform infrared spectroscopy were studied to characterize size,structure,morphology,and binding of enzyme onto the nanoparticles.The stability and activity of the bound cellulase was analyzed using various parameters including pH,temperature,reusability,and storage stability.The immobilized cellulase was compared with free cellulase and it shows enhanced stability and activity.展开更多
文摘AIM： To assess the prevalence and socio-demographic distribution of hepatitis B virus （HBV） infection in Albania. METHODS： Blood samples from 410 unselected schoolboys, 666 students, 500 military personnel, 1286 casual blood donors, 378 voluntary blood donors and 640 pregnant women （total 3880 non-vaccinated residents of rural and metropolitan areas from all over Albania; 2354 （60.7%） male and 1526 （39.3%） female; mean age of 26.3 years） were tested during 2004-2006 for hepatitis B surface antigen （HBsAg） and antibodies to hepatitis B virus （anti-HBs） by ELISA. RESULTS： The HBsAg and anti-HBs prevalence were 9.5% and 28.7%, respectively. The highest HI3sAg prevalence was evident in the younger age group, such as in schoolchildren （11.8%） and the military （10.6%）. Consequently, the anti-HBs prevalence increased with age, from 21.2% in schoolchildren （mean age： 15.7 years）, to 36.3% in pregnant women （mean age： 26.3 years） and 29.7% in voluntary blood donors （mean age： 40.1 years）. There were no significant differences between males and females. CONCLUSION： Despite the estimated two-fold reduction of HBsAg prevalence in the general population from about 18%-19% to 9.5%, Albania remains a highly endemic country （i.e. over 8% of HBsAg prevalence rate）.
文摘Gelatinase A (MMP-2) is considered to play a critical role in cell migration and invasion. The proteinase is secreted from the cell as an inactive zymogen. In vivo it is postulated that activation of progelationase A (proMMP-2) takes place on the cell surface mediated by membrane-type matrix metalloproteinases (MT-MMPs). Recent studies have demonstrated that proMMP-2 is recruited to the cell surface by interacting with tissue inhibitor of metalloproteinases-2 (TIMP-2) bound to MT1MMP by forming a ternary complex. bee MT1-MMP closely located to the ternary complex then activates proMMP-2 on the cell surface. MT1-MMP is found in cultured invasive cancer cells at the invadopodia. The MTMMP/TIMP-2/ MMP- 2 system t bus provides localized expression of proteolysis of the extracellular matrix required for cell migration.
基金Supported by the National High Technology Research and Development Program of China （2006AA02Z211）, the National Natural Science Foundation of China （20376034）, the Natural Science Foundation of Jiangsu Province （BK2006181）, and the Foundation of Jiangsu Province for College Postgraduate Students in Innovation Engineering （2007）.
文摘Complexation and interaction between silver and amino group were applied to induce an efficient immobilization of papain on silica spheres.Tbe silver nanoparticles were deposited on the silica spheres before p apainwas coupled to the silica spheres. The silica spheres with silver nanoparticles were characterized by high resolution transmission electron microscopy （HR-TEM）, Fournier transform infrared spectroscopy （FT-IR）, and UV-Vis scanning spectrometer. FT-IR spectrum was also used to characterize the immobilized and free papain. Effect of some factors on the activities of the immobilized papain was investigated. It was observed that the coupled yield and relative activity of the papain on Ag/SiO2 were 1.17 and 1.86 times of those on the bare SiO2, respectively. At an optimum concentration of silver, theobserved activity of the immobilized papain was 2.1 timesof that on the bare.silica.In addition, the maximum specific activity of papain immobilized on Ag/SiO2 was 819.9 U·mg·^-1, which is slightly lower than that of the free papain, 906.2 U·mg^-1 . Stability of the immobilized papain was also examined. The resuits indicate that the silver nanoparticles successfully induce a fine immobilization of papain.
基金Supported by the National Natural Science Foundation of China （20676071, 20836004）.
文摘In order to study the effects of ionic surfactants on bacterial luciferase,the cationic surfactant dodecyltrimethylammonium biomide (DTAB) and anionic surfactant sodium dodecylsulfate (SDS) were chosen.For comparison with bacterial luciferase,α-amylase was used since these two enzymes have similar electrostatic potential and charged active sites.After the enzymes were treated with the surfactants,the catalytic properties of bacterial luciferase andα-amylase were assayed,and fluorescence spectroscopy and circular dichroism (CD) were used to analyze the alteration of the protein structure.The results showed that when the DTAB concentration was low,the cationic surfactant DTAB enhanced the enzymatic activities of bacterial luciferase andα-amylase.On the other hand,the anionic surfactant SDS did not alter the enzymatic activity.The main interaction of cationic surfactant DTAB and the negatively charged surface of the proteins was the ionic interaction,which could alter the environment for the enzyme to work when the DTAB/enzyme molar ratio was low.However,at high cationic surfactant concentration,the ionic interaction and hydrophobic interaction might destroy the secondary and tertiary structures of the proteins,leading to the loss of enzymatic activities.
基金Supported by The Department of Health of Jiangsu Province,China,No.H200957
文摘AIM： To evaluate the clinical significance of CpG island methylator phenotype （CIMP） in plasma and its association with hepatocellular carcinoma （HCC） progress. METHODS： CIMP status of 108 HCC patients was analyzed using a methylation marker panel in tumor tissues and plasma with methylation-specific polymerase chain reaction. Fifteen samples of non-neoplastic liver tissues and 60 of plasma from healthy persons were examined simultaneously. Examined genes included APC, WIF-1, RUNX-3, DI C-1, SFRP-1, DKK and E-cad.26/108, 24.07% in plasma; WIF-1, 53/108, 49.07% in tissue and 35/108, 32.41% in plasma; RUNX-3, 52/108, 48.14% in tissue and 42/108, 38.89% in plasma; DIC-1, 38/108, 35.18% in tissue and 23/108, 21.30% in plasma; SFRP-1, 40/108, 37.04% in tissue and 31/108, 28.7% in plasma; DKK, 39/108, 36.1% in tis- sue and 25/108, 23.14% in plasma; and E-cad, 37/108, 34.3% in tissue and 18/108, 16.67% in plasma. CIMP＋ （≥3 methylated genes） was detected in 68 （60.2%） tumor tissue samples and 62 （57.4%） plasma samples. CIMP was not detected in non-neoplastic liver tissues or plasma of healthy persons. CIMP status in tumor tissues differed significantly in gender, hepatitis B surface antigen, alpha-fetoprotein, and tumor-node- metastasis stage （P 〈 0.05）. Similar results were obtained with plasma samples （P 〈 0.05）. There was no difference in CIMP status in age, presence of hepatitis C virus antibody, cirrhosis, number of nodes, number of tumors, tumor size, or Edmondson-Steiner stage. A one-year follow-up found that the metastatic rate and recurrence rate in the CIMP＋ group were significantly higher than in the CIMP- group as assessed with plasma samples （P 〈 0.05）. CONCLUSION： Plasma DNA can be a reliable sample source for CIMP analysis. CIMP in plasma may serve as a molecular marker of late-stage and poor-prognosis HCC.
文摘The optimization of cultural conditions for β glucanase production by Bacillus subtilis ZJF 1A5 was investigated in flask trials. Temperature had great effect on β glucanase production which maximized at optimal temperature of 37℃ and decreased significantly when temperature was over 37℃.Charge quantity affected β glucanase production significantly. Adding oxygen vector N dodecane or acetic ether benefited β glucanase production, but it depended on the concentration and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were the key factors affecting β glucanase production and the cultivation time span to reach the highest β glucanase activity. The optimal cultural conditions for β glucanase production obtained with CCD were as follows: inoculum age and size (16 h, 3.82%(v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37℃ for 50 h. Repeated experimental results accorded with those predicted by a second order polynomial model. The amount of β glucanase, α amylase and neutral protease produced by B subtilis ZJF 1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and increased significantly when cells entered the stationary phase.
文摘The aim of this research is to study the floatation deinking abilities of black mold enzyme and chemicals in newsprint paper application. In this experiment, the properties of deinked pulp from three different additives--chemicals, black mold enzyme, and chemicals together with black mold enzyme, are studied. The first part of the experiment was to find the optimal amount of chemicals and the optimal pH through the use of sodium hydroxide and surfactant. As a result, 0.2% of sodium hydroxide and 0.4% of surfactant on oven dried weight at pH 9 was found to be the optimal condition for the deinked pulp to yield the lowest ERIC （effective residual concentration） and the highest brightness. The second part of the experiment was to find the optimal amount of black mold enzyme used in the deinking process. As a result, the optimal condition for deinked pulp to retain the lowest ERIC and the highest brightness was 100 ppm of black mold enzyme and 10 minutes of enzyme reaction time. The third part of experiment was to study the de-inking ability of black mold enzyme and chemicals. Consequently, with 30 min of chemicals reaction time and 60 min of black mold reaction time, the deinked pulp retained low ERIC but higher brightness.
文摘Magnetic nanoparticles（Fe3O4） were synthesized by co-precipitating Fe^2＋ and Fe^3＋ ions in an ammonia solution and treating under hydrothermal conditions.Cellulase was immobilized onto Fe3O4 magnetic nanoparticles via glutaraldehyde activation.Using response surface methodology and Box-Behnken design,the variables such as magnetic nanoparticle concentration,glutaraldehyde concentration,enzyme concentration,and cross linking time were optimized.The Box-Behnken design analysis showed a reasonable adjustment of the quadratic model with the experimental data.Statistical contour plots were generated to evaluate the changes in the response surface and to understand the relationship between the nanoparticles and the enzyme activity.Scanning electron microscopy,X-ray diffraction analysis,and Fourier transform infrared spectroscopy were studied to characterize size,structure,morphology,and binding of enzyme onto the nanoparticles.The stability and activity of the bound cellulase was analyzed using various parameters including pH,temperature,reusability,and storage stability.The immobilized cellulase was compared with free cellulase and it shows enhanced stability and activity.
