AIM： To study the variabilities of serum proteomic spectra in patients with gastric cancer before and after operation in order to detect the specific protein markers that can be used for quick diagnosis of gastric ca...AIM： To study the variabilities of serum proteomic spectra in patients with gastric cancer before and after operation in order to detect the specific protein markers that can be used for quick diagnosis of gastric cancer. METHODS： Proteomic spectra of 46 serum samples from patients with gastric cancer before and after operation and 40 from normal individuals were generated by IMAC-Cu protein chip and surface-enhanced laser desorption/ionization time of flight mass spectrometry. RESULTS： Fourteen differentially expressed proteins in serum were screened by analysis of proteomic spectra of preoperative patients and normal individuals. We obtained 4 proteins （heat shock protein 27, glucoseregulated protein, prohibitin, protein disulfide isomerase A3） making up marker pattern which was able to class the patient-team and normal-team. These marker patterns yielded 95.7% sensitivity and 92.5% specificity, respectively. The proteins over-expressed in serum of preoperative patients were obviously down-regulated. CONCLUSION： Specific protein markers of gastric cancer can be used for the quick diagnosis of gastric cancer and judgment of prognosis. SELDI-TOF-MS is a useful tool for the detection and identification of new protein markers in serum.展开更多
AIM： To identify a multi serum protein pattern as well as single protein markers using surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry （SELDI-TOF-MS） for detection and differentiation ...AIM： To identify a multi serum protein pattern as well as single protein markers using surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry （SELDI-TOF-MS） for detection and differentiation of liver fibrosis （F1-F2）, liver cirrhosis （F4） and hepatocellular carcinoma （HCC） in patients with chronic hepatitis C virus （HCV）. METHODS： Serum samples of 39 patients with F1/F2 fibrosis, 44 patients with F4 fibrosis, 34 patients with HCC were applied to CM10 arrays and analyzed using the SELDI-TOF ProteinChip System （PBS-Ⅱc; Ciphergen Biosystems） after anion-exchange fractionation. All patients had chronic hepatitis C and histologically confirmed fibrosis stage/HCC. Data were analyzed for protein patterns by multivariate statistical techniques and artificial neural networks. RESULTS： A 4 peptide/protein multimarker panel （7486, 12843, 44293 and 53598 Da） correctly identified HCCs with a sensitivity of 100% and specificity of 85% in a two way-comparison of HCV-cirrhosis versus HCV-HCC training samples （AUROC 0.943）. Sensitivity and specificity for identification of HCC were 68% and 80% for random test samples. Cirrhotic patients could be discriminated against patients with F1 or F2 fibrosis using a 5 peptide/protein multimarker pattern （2873, 6646, 7775, 10525 and 67867 Da） with a specificity of 100% and a sensitivity of 85% in training samples （AUROC 0.976） and a sensitivity and specificity of 80% and 67% for random test samples. Combination of the biomarker classifiers with APR/score and alfa-fetopotein （AFP） improved the diagnostic performance. The 6646 Da marker protein for liver fibrosis was identified as apolipoprotein C-I. CONCLUSION： SELDI-TOF-MS technology combined with protein pattern analysis seems a valuable approach for the identification of liver cirrhosis and hepatocellular carcinoma in patients with chronic hepatitis C. Host probably a combination of different serum markers will help to identify liver cirrhosis and early-stage hep展开更多
The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterize...The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） and nuclear magnetic resonance （NMR） analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing/antioxidant power （FRAP） model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.展开更多
AIM:To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics.METHODS:Proportional peptide mas...AIM:To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics.METHODS:Proportional peptide mass fingerprints were obtained by analysis based on proteomics matrix-assisted laser desorption ionization time-of-flight/mass spectrometry.A diagnosis model was established using weak cation exchange magnetic beads to test saliva specimens from gastric cancer patients and healthy subjects.RESULTS:Significant differences were observed in the mass to charge ratio(m/z) peaks of four proteins(1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da) between gastric cancer patients and healthy subjects.CONCLUSION:The finger print mass spectrum of saliva protein in patients with gastric cancer can be established using gastric cancer proteomics.A diagnostic model for distinguishing protein expression mass spectra of gastric cancer from non-gastric-cancer saliva can be established according to the different expression of proteins 1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da.The method for early diagnosis of gastric cancer is of certain value for screening special biological markers.展开更多
Objective: Biomarker assay is a noninvasive method for the early detection of esophageal squamous cellcarcinoma (ESCC). Searching for new biomarkers with high specificity and sensitivity is very important for the earl...Objective: Biomarker assay is a noninvasive method for the early detection of esophageal squamous cellcarcinoma (ESCC). Searching for new biomarkers with high specificity and sensitivity is very important for the earlydetection of ESCC. Serum surface-enhanced laser desorption/ionization-time of flight mass spectrometry(SELDI-TOF-MS) is a high throughput technology for identifying cancer biomarkers using drops of sera. Methods: Inthis study, 185 serum samples were taken from ESCC patients in a high incidence area and screened by SELDI. Asupport vector machine (SVM) algorithm was adopted to analyze the samples. Results: The SVM patterns success-fully distinguished ESCC from pre-cancerous lesions (PCLs). Also, types of PCL, including dysplasia (DYS) and basalcell hyperplasia (BCH), and healthy controls (HC) were distinguished with an accuracy of 95.2% (DYS), 96.6% (BCH),and 93.8% (HC), respectively. A marker of 25.1 kDa was identified in the ESCC patterns whose peak intensity wasobserved to increase significantly during the development of esophageal carcinogenesis, and to decrease obviously after surgery. Conclusions: We selected five ESCC biomarkers to form a diagnostic pattern which can discriminateamong the different stages of esophageal carcinogenesis. This pattern can significantly improve the detection ofESCC.展开更多
Serum samples from endometrial cancer (EC) patients and healthy females were analyzed using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to discover the potential diagno...Serum samples from endometrial cancer (EC) patients and healthy females were analyzed using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to discover the potential diagnostic biomarker for detection of EC. A preliminary training set of spectra derived from 40 EC patients and 30 healthy women were used to develop a proteomic model that effectively discriminated cancer patients from healthy women. The training set had a specificity of 100% and sensitivity of 92.5% in the EC detection. A blind test set, including 20 new cancer cases and 10 healthy women, was used to validate the sensitivity and specificity of this multivariate model, which had a corresponding results of 60% in specificity and 75% in sensitivity, respectively. The combination of SELDI-TOF-MS with bioinformatics tools could help find new biomarkers and establish the detection of EC with high sensitivity and specificity.展开更多
Protein analysis is vital for biological and clinical research, but the measurement of unseparated, intact and high-mass proteins is also a challenging task by mass spectrometry-based methods. Here, we present a proto...Protein analysis is vital for biological and clinical research, but the measurement of unseparated, intact and high-mass proteins is also a challenging task by mass spectrometry-based methods. Here, we present a protocol for rapid and high-throughput analysis of intact proteins in tissue samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDITOF MS） combined with a high-mass detector platform. The method involves tissue specimens that undergo a simple protein extraction before MALDI-MS analysis. Using this method, the high abundance proteins in human thyroid carcinoma and paracarcinoma tissues were successfully investigated, and the mass spectra of the tissues of the 30 illustrated thyroid cancers showed remarkable differences. The peak intensity revealed a significant increase in human albumin in thyroid carcinoma tissues（p＆lt;0.05）. To validate the feasibility and credibility of this method, label-free proteomics quantitative analysis and Western blotting were used to relatively quantify the proteins in these tissues. Those results demonstrated a nearly 3-fold difference in human albumin levels between thyroid carcinoma and para-carcinoma tissues, which were consistent with the results of our method. The advantages of our method are easy sample handling, remarkable reproducibility and the ability to analyze high-mass proteins without digestion, which make them have the potential to be used in biological research and in clinical practice.展开更多
AIM： To investigate the relationship between urinary peptide changes and Helicobacter pylori （H. pylorl） infection using urinary peptidome profiling. METHODS： The study was performed in volunteers （n = 137） who ...AIM： To investigate the relationship between urinary peptide changes and Helicobacter pylori （H. pylorl） infection using urinary peptidome profiling. METHODS： The study was performed in volunteers （n = 137） who gave informed consent. Urinary peptides were enriched by magnetic beads based weak cation exchange chromatography＇and spectrums acquired by matrix-assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry （MS）. ClinProTools bioinformatics software was used for statistical analysis and the recognition of peptide patterns. The marker peptides were identified by LTQ Obitrap XL tandem MS. RESULTS： Approximately 50 proteins or peptides which loaded onto the magnetic beads were detected by MAL-DI-TOF MS. By optimizing the parameters of the model, the Genetic Algorithm model had good recognition capability （97%） and positive predictive value （94%）. Based on the model, 2 markers with molecular masses of 6788 and 1912 Da were found that differentiated between H. pylori positive and negative volunteers. The m/z 1912 sequence was parsed as SKQFTSSTSYN- RGDSTF. The peptide was identified as isoform 1 of the fibrinogen a chain precursor, whose concentration in urine was markedly higher in H. pylori infected volunteers than in H. pylori non-infected ones. CONCLUSION： The appearance of urinary fibrinogen degradation products is caused by an active H. pyloriinduced process.展开更多
Rationale:Nocardia is a soil saprophyte,which can cause disseminated infection in immunocompromised patients.Early diagnosis and treatment can greatly improve prognosis.Patient concern:A 26-year-old male presented wit...Rationale:Nocardia is a soil saprophyte,which can cause disseminated infection in immunocompromised patients.Early diagnosis and treatment can greatly improve prognosis.Patient concern:A 26-year-old male presented with repeated episodes of fever,cough and breathlessness for 3 months.Diagnosis:Mixed infection of Nocardia(N.)farcinica and N.cyriacigeorgica with diabetes and Cushing’s syndrome.Interventions:N.cyriacigeorgica was isolated from empyema fluid and N.farcinica from blood.Based on antimicrobial susceptibility,he was treated with imipenem,cotrimoxazole and amikacin.Outcome:Patient expired due to infection and delayed diagnosis.Lesson:Several cases of infection due to N.farcinica or N.cyriacigeorgica have been reported.But mixed infection caused by these two species is rare.Pulmonary and disseminated nocardiosis is associated with high mortality,especially in immunocompromised hosts.So early diagnosis and prompt treatment is needed.展开更多
Background Freshwater snails of the genera Bulinus spp.,Biomphalaria spp.,and Oncomelania spp.are the main intermediate hosts of human and animal schistosomiasis.Identification of these snails has long been based on m...Background Freshwater snails of the genera Bulinus spp.,Biomphalaria spp.,and Oncomelania spp.are the main intermediate hosts of human and animal schistosomiasis.Identification of these snails has long been based on mor-phological and/or genomic criteria,which have their limitations.These limitations include a lack of precision for the morphological tool and cost and time for the DNA-based approach.Recently,Matrix-Assisted Laser Desorp-tion/lonization Time-Of-Flight(MALDI-TOF)mass spectrometry,a new tool used which is routinely in clinical microbi-ology,has emerged in the field of malacology for the identification of freshwater snails.This study aimed to evaluate the ability of MALDI-TOF MS to identify Biomphalaria pfeifferi and Bulinus forskali snail populations according to their geographicalorigin.Methods This study was conducted on 101 Bi.pfeifferi and 81 Bu.forskali snails collected in three distinct geo-graphical areas of Senegal(the North-East,South-East and central part of the country),and supplemented with wild and laboratory strains.Specimens which had previously been morphologically described were identified by MALDl-TOF MS[identification log score values(LSV)≥1.7],after an initial blind test using the pre-existing database.After DNA-based identification,new reference spectra of Bi.pfeiferi(n=10)and Bu.forskali(n=5)from the geographical areas were added to the MALDI-TOF spectral database.The final blind test against this updated database was per-formed to assess identification at the geographic source level.Results MALDI-TOF MS correctly identified 92.1%of 101 Bi.pfeifferi snails and 98.8%of 81 Bu.forskali snails.At the final blind test,88%of 166 specimens were correctly identified according to both their species and sampling site,with LSVs ranging from 1.74 to 2.70.The geographical source was adequately identified in 90.1%of 91 Bi.pfeifferi and 85.3%of 75 Bu.forskalii samples.Conclusions Our findings demonstrate that MALDI-TOF MS can identify and differentiate snail populations according to geograph展开更多
Objective: Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB), screening out and iden...Objective: Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB), screening out and identifying the differentially expressed proteins by mass spectrometry and bioinformatics analysis, discussing the molecular mechanism of control the Diabetes deafness by GEPRB. Methods: By use of proteomics technology, the serum protein serum proteome of the control group, model control group, Duxil and each observation group were observed for 2-DE gel pattern matching, and the difference in the relative content of 2 times was chosen for the differentially expressed proteins. Identification of differentially expressed proteins by MALDI-TOF MS/MS, the authors further analysis the phosphorylation, subcellular localization, interaction, direct regulation, and transmembrane of the differences proteins by the way of bioinformatics analysis. Sixty SPF level SD rats elected in diabetic rats model group (abbreviated as DM group) were be randomly divided into 5 groups based on random number sheet, namely model control group, positive drug control group (Du-ke-xi group) and Mai-tong-fang high, medium and low dose group respectively. In addition, set of normal control group. 10 rats in each group. Results: By Coomassie brilliant blue staining, identified 51 differential protein spots dug from 2-D gel by mass spectrometry, successfully identified 13 non-redundant proteins. Most of the identified proteins were secreted protein and belong to different protein families. There were about 12 proteins have the transmembrane region from the authors’ result, ten of them were plasma membrane proteins. Conclusion: It’s suggesting that 13 differential proteins is most likely the protein response to GEPRB in vivo, these proteins may play key role for the treatment of GEPRB to Diabetes deafness. The two highly differentially expressed proteins Apolipoprotein E (apoE) and C3 may be a potential drug target of GEPRB.展开更多
1 Introduction C<sub>60</sub> and other cage-like carbon molecules, or the fullerenes, have become one ofthe most interesting materials in physics, chemistry and materials science in recentyears. In 1985, ...1 Introduction C<sub>60</sub> and other cage-like carbon molecules, or the fullerenes, have become one ofthe most interesting materials in physics, chemistry and materials science in recentyears. In 1985, C<sub>60</sub><sup>+</sup> ion was found to be prominent in the laser-ablation mass spec-trum of graphite and unusual stability was proposed for C<sub>60</sub> later. The discovery byKratschmer and his co-workers of a method for producing macroscopic.quantities ofC<sub>60</sub> and C<sub>70</sub> in 1990 has stimulated great interest to investigate the properties of C<sub>60</sub>and other fullerenes. Many papers have been concerned with the dissociationand stability of C<sub>60</sub> and its ions. Studies of C<sub>60</sub><sup>+</sup> dissociation by means展开更多
Isolation and comparison of uremic sera and urine and normal sera and urine were performed by gel permeation chromatography, anion exchange chromatography and reversed-phase high performance liquid chromatography. Two...Isolation and comparison of uremic sera and urine and normal sera and urine were performed by gel permeation chromatography, anion exchange chromatography and reversed-phase high performance liquid chromatography. Two uremic middle molecular fractions (A and B) were obtained from uremic sera and urine and normal urine by gel permeation chromatography, but not from normal sera. The anion exchange chromatographic results of fraction A from different origins demonstrate that subfraction A-3 could be excreted in urine by healthy subject, but accumulated in uremic serum for renal failure of patient with uremia. After desalinization subfraction A-3 was analyzed by MALDI-TOF-MS. The results show that subfraction A-3 consists of six compounds with molecular weight 839, 873, 1007.94, 1106, 1680 and 2015 respectively. Finally, by reversed-phase high performance liquid chromatography, subfraction A-3 was further resolved into six independent fractions. Thus, the isolation and purification of six middle molecular compounds in subfraction A-3 came true by our method.展开更多
20-Hydroxyecdysone(20E)derived from plants has a wide range of physiological and pharmacological ef ects on animals and humans,and rapid and sensitive methods for screening of the endogenous 20E in plants are thus req...20-Hydroxyecdysone(20E)derived from plants has a wide range of physiological and pharmacological ef ects on animals and humans,and rapid and sensitive methods for screening of the endogenous 20E in plants are thus required.Herein,a matrixassisted laser desorption/ionization time-of-f ight tandem mass spectrometry(MALDI-TOF/TOF MS)method is described for rapid and sensitive determination of endogenous 20E in plants.It is based on the use of the(3-(acridin-9-ylamino)phenyl)boronic acid(AYPBA)as the mass tag to assist the MS and tandem MS(MS^(n))analysis of 20E on MALDI-TOF/TOF MS.Good linearity was obtained with a determination coef cient(R^(2))larger than 0.99 in the range of 0.025–2.5μΜ.The limit of detection(LOD)was 2.4 fmol.Acceptable precision and accuracy were gained by intra-and inter-day analysis with relative standard deviations less than 19.5%and relative recoveries ranging from 85.7 to 105.2%.In addition,the AYPBA labeled 20E produced abundant characteristic fragment ions under the high energy collision-induced dissociation,which facilitated the identif cation of 20E by MS^(2)analysis on MALDI-TOF/TOF MS.Using the method,we enabled the identif cation and quantif cation of endogenous 20E in four herbs including Cyanotis arachoidea,Achyranthes bidentata,Spinacia oleracea and Chenopodium quinoa willd.,demonstrating the feasibility of the proposed method for screening of the endogenous 20E in plants.展开更多
With the advantages on non-equilibrium heating and desorption induced by electronic transition, the femtosecond pulse laser introduces a new way for solving the problem of impurity pollution adsorbed on a solid thin f...With the advantages on non-equilibrium heating and desorption induced by electronic transition, the femtosecond pulse laser introduces a new way for solving the problem of impurity pollution adsorbed on a solid thin film in micro-electro-mechanical systems (MEMS). A model based on stochastic processes was established for stimulated desorption induced by the femtosecond pulse laser to interpret the interaction of the opti-cally excited hot electrons with the adsorbed molecules in a metal substrate. Numerical simulation results reveal a time-dependent desorption probability of adsorbed molecules and indicate that how key parameters of femtosecond pulse laser, such as incident laser energy flux, pulse duration, and wavelength of pulse, have a great effect on the desorption probability.展开更多
文摘AIM： To study the variabilities of serum proteomic spectra in patients with gastric cancer before and after operation in order to detect the specific protein markers that can be used for quick diagnosis of gastric cancer. METHODS： Proteomic spectra of 46 serum samples from patients with gastric cancer before and after operation and 40 from normal individuals were generated by IMAC-Cu protein chip and surface-enhanced laser desorption/ionization time of flight mass spectrometry. RESULTS： Fourteen differentially expressed proteins in serum were screened by analysis of proteomic spectra of preoperative patients and normal individuals. We obtained 4 proteins （heat shock protein 27, glucoseregulated protein, prohibitin, protein disulfide isomerase A3） making up marker pattern which was able to class the patient-team and normal-team. These marker patterns yielded 95.7% sensitivity and 92.5% specificity, respectively. The proteins over-expressed in serum of preoperative patients were obviously down-regulated. CONCLUSION： Specific protein markers of gastric cancer can be used for the quick diagnosis of gastric cancer and judgment of prognosis. SELDI-TOF-MS is a useful tool for the detection and identification of new protein markers in serum.
基金Supported by a research grant of the Jurgen Manchot Stiftung
文摘AIM： To identify a multi serum protein pattern as well as single protein markers using surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry （SELDI-TOF-MS） for detection and differentiation of liver fibrosis （F1-F2）, liver cirrhosis （F4） and hepatocellular carcinoma （HCC） in patients with chronic hepatitis C virus （HCV）. METHODS： Serum samples of 39 patients with F1/F2 fibrosis, 44 patients with F4 fibrosis, 34 patients with HCC were applied to CM10 arrays and analyzed using the SELDI-TOF ProteinChip System （PBS-Ⅱc; Ciphergen Biosystems） after anion-exchange fractionation. All patients had chronic hepatitis C and histologically confirmed fibrosis stage/HCC. Data were analyzed for protein patterns by multivariate statistical techniques and artificial neural networks. RESULTS： A 4 peptide/protein multimarker panel （7486, 12843, 44293 and 53598 Da） correctly identified HCCs with a sensitivity of 100% and specificity of 85% in a two way-comparison of HCV-cirrhosis versus HCV-HCC training samples （AUROC 0.943）. Sensitivity and specificity for identification of HCC were 68% and 80% for random test samples. Cirrhotic patients could be discriminated against patients with F1 or F2 fibrosis using a 5 peptide/protein multimarker pattern （2873, 6646, 7775, 10525 and 67867 Da） with a specificity of 100% and a sensitivity of 85% in training samples （AUROC 0.976） and a sensitivity and specificity of 80% and 67% for random test samples. Combination of the biomarker classifiers with APR/score and alfa-fetopotein （AFP） improved the diagnostic performance. The 6646 Da marker protein for liver fibrosis was identified as apolipoprotein C-I. CONCLUSION： SELDI-TOF-MS technology combined with protein pattern analysis seems a valuable approach for the identification of liver cirrhosis and hepatocellular carcinoma in patients with chronic hepatitis C. Host probably a combination of different serum markers will help to identify liver cirrhosis and early-stage hep
基金Project supported by the National Natural Science Foundation of China (No. 30671646)the Program for New Century Excellent Talents in University, China (No. NCET-07-0725)the Program for Innovative Research Team in Science and Technology in Fujian Province University, China
文摘The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） and nuclear magnetic resonance （NMR） analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing/antioxidant power （FRAP） model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.
基金Supported by The National Natural Science Foundation of China,No. 30640071
文摘AIM:To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics.METHODS:Proportional peptide mass fingerprints were obtained by analysis based on proteomics matrix-assisted laser desorption ionization time-of-flight/mass spectrometry.A diagnosis model was established using weak cation exchange magnetic beads to test saliva specimens from gastric cancer patients and healthy subjects.RESULTS:Significant differences were observed in the mass to charge ratio(m/z) peaks of four proteins(1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da) between gastric cancer patients and healthy subjects.CONCLUSION:The finger print mass spectrum of saliva protein in patients with gastric cancer can be established using gastric cancer proteomics.A diagnostic model for distinguishing protein expression mass spectra of gastric cancer from non-gastric-cancer saliva can be established according to the different expression of proteins 1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da.The method for early diagnosis of gastric cancer is of certain value for screening special biological markers.
基金Project supported by the National Natural Science Foundation of China (No. 30901731)the Fundamental Research Funds for the Central Universities (No. 2012FZA7004), China
文摘Objective: Biomarker assay is a noninvasive method for the early detection of esophageal squamous cellcarcinoma (ESCC). Searching for new biomarkers with high specificity and sensitivity is very important for the earlydetection of ESCC. Serum surface-enhanced laser desorption/ionization-time of flight mass spectrometry(SELDI-TOF-MS) is a high throughput technology for identifying cancer biomarkers using drops of sera. Methods: Inthis study, 185 serum samples were taken from ESCC patients in a high incidence area and screened by SELDI. Asupport vector machine (SVM) algorithm was adopted to analyze the samples. Results: The SVM patterns success-fully distinguished ESCC from pre-cancerous lesions (PCLs). Also, types of PCL, including dysplasia (DYS) and basalcell hyperplasia (BCH), and healthy controls (HC) were distinguished with an accuracy of 95.2% (DYS), 96.6% (BCH),and 93.8% (HC), respectively. A marker of 25.1 kDa was identified in the ESCC patterns whose peak intensity wasobserved to increase significantly during the development of esophageal carcinogenesis, and to decrease obviously after surgery. Conclusions: We selected five ESCC biomarkers to form a diagnostic pattern which can discriminateamong the different stages of esophageal carcinogenesis. This pattern can significantly improve the detection ofESCC.
基金Project (No. 985-2-015-24) partly supported by "985" Project of Research Grants from Peking University, China
文摘Serum samples from endometrial cancer (EC) patients and healthy females were analyzed using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to discover the potential diagnostic biomarker for detection of EC. A preliminary training set of spectra derived from 40 EC patients and 30 healthy women were used to develop a proteomic model that effectively discriminated cancer patients from healthy women. The training set had a specificity of 100% and sensitivity of 92.5% in the EC detection. A blind test set, including 20 new cancer cases and 10 healthy women, was used to validate the sensitivity and specificity of this multivariate model, which had a corresponding results of 60% in specificity and 75% in sensitivity, respectively. The combination of SELDI-TOF-MS with bioinformatics tools could help find new biomarkers and establish the detection of EC with high sensitivity and specificity.
基金supported by the National Natural Science Foundation of China (21672250)Chinese Academy of Sciences (YZ201544)+1 种基金National Key Technology Support Program (2015BAK45B01)the Shanghai Municipal Planning Commission of Science and Research Fund for Young Scholar (20154Y0050)
文摘Protein analysis is vital for biological and clinical research, but the measurement of unseparated, intact and high-mass proteins is also a challenging task by mass spectrometry-based methods. Here, we present a protocol for rapid and high-throughput analysis of intact proteins in tissue samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDITOF MS） combined with a high-mass detector platform. The method involves tissue specimens that undergo a simple protein extraction before MALDI-MS analysis. Using this method, the high abundance proteins in human thyroid carcinoma and paracarcinoma tissues were successfully investigated, and the mass spectra of the tissues of the 30 illustrated thyroid cancers showed remarkable differences. The peak intensity revealed a significant increase in human albumin in thyroid carcinoma tissues（p＆lt;0.05）. To validate the feasibility and credibility of this method, label-free proteomics quantitative analysis and Western blotting were used to relatively quantify the proteins in these tissues. Those results demonstrated a nearly 3-fold difference in human albumin levels between thyroid carcinoma and para-carcinoma tissues, which were consistent with the results of our method. The advantages of our method are easy sample handling, remarkable reproducibility and the ability to analyze high-mass proteins without digestion, which make them have the potential to be used in biological research and in clinical practice.
基金Supported by The National Science and Technology Pillar Program of the Ministry of Science and Technology of the People’s Republic of China during the Eleventh Five-Year plan period,No. 2007BAID4B02
文摘AIM： To investigate the relationship between urinary peptide changes and Helicobacter pylori （H. pylorl） infection using urinary peptidome profiling. METHODS： The study was performed in volunteers （n = 137） who gave informed consent. Urinary peptides were enriched by magnetic beads based weak cation exchange chromatography＇and spectrums acquired by matrix-assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry （MS）. ClinProTools bioinformatics software was used for statistical analysis and the recognition of peptide patterns. The marker peptides were identified by LTQ Obitrap XL tandem MS. RESULTS： Approximately 50 proteins or peptides which loaded onto the magnetic beads were detected by MAL-DI-TOF MS. By optimizing the parameters of the model, the Genetic Algorithm model had good recognition capability （97%） and positive predictive value （94%）. Based on the model, 2 markers with molecular masses of 6788 and 1912 Da were found that differentiated between H. pylori positive and negative volunteers. The m/z 1912 sequence was parsed as SKQFTSSTSYN- RGDSTF. The peptide was identified as isoform 1 of the fibrinogen a chain precursor, whose concentration in urine was markedly higher in H. pylori infected volunteers than in H. pylori non-infected ones. CONCLUSION： The appearance of urinary fibrinogen degradation products is caused by an active H. pyloriinduced process.
文摘AIM: To develop a method to differentiate pancreatic cancer patients from healthy or benign individuals when carbohydrate antigen (CA) 19-9 is normal.
文摘Rationale:Nocardia is a soil saprophyte,which can cause disseminated infection in immunocompromised patients.Early diagnosis and treatment can greatly improve prognosis.Patient concern:A 26-year-old male presented with repeated episodes of fever,cough and breathlessness for 3 months.Diagnosis:Mixed infection of Nocardia(N.)farcinica and N.cyriacigeorgica with diabetes and Cushing’s syndrome.Interventions:N.cyriacigeorgica was isolated from empyema fluid and N.farcinica from blood.Based on antimicrobial susceptibility,he was treated with imipenem,cotrimoxazole and amikacin.Outcome:Patient expired due to infection and delayed diagnosis.Lesson:Several cases of infection due to N.farcinica or N.cyriacigeorgica have been reported.But mixed infection caused by these two species is rare.Pulmonary and disseminated nocardiosis is associated with high mortality,especially in immunocompromised hosts.So early diagnosis and prompt treatment is needed.
文摘Background Freshwater snails of the genera Bulinus spp.,Biomphalaria spp.,and Oncomelania spp.are the main intermediate hosts of human and animal schistosomiasis.Identification of these snails has long been based on mor-phological and/or genomic criteria,which have their limitations.These limitations include a lack of precision for the morphological tool and cost and time for the DNA-based approach.Recently,Matrix-Assisted Laser Desorp-tion/lonization Time-Of-Flight(MALDI-TOF)mass spectrometry,a new tool used which is routinely in clinical microbi-ology,has emerged in the field of malacology for the identification of freshwater snails.This study aimed to evaluate the ability of MALDI-TOF MS to identify Biomphalaria pfeifferi and Bulinus forskali snail populations according to their geographicalorigin.Methods This study was conducted on 101 Bi.pfeifferi and 81 Bu.forskali snails collected in three distinct geo-graphical areas of Senegal(the North-East,South-East and central part of the country),and supplemented with wild and laboratory strains.Specimens which had previously been morphologically described were identified by MALDl-TOF MS[identification log score values(LSV)≥1.7],after an initial blind test using the pre-existing database.After DNA-based identification,new reference spectra of Bi.pfeiferi(n=10)and Bu.forskali(n=5)from the geographical areas were added to the MALDI-TOF spectral database.The final blind test against this updated database was per-formed to assess identification at the geographic source level.Results MALDI-TOF MS correctly identified 92.1%of 101 Bi.pfeifferi snails and 98.8%of 81 Bu.forskali snails.At the final blind test,88%of 166 specimens were correctly identified according to both their species and sampling site,with LSVs ranging from 1.74 to 2.70.The geographical source was adequately identified in 90.1%of 91 Bi.pfeifferi and 85.3%of 75 Bu.forskalii samples.Conclusions Our findings demonstrate that MALDI-TOF MS can identify and differentiate snail populations according to geograph
文摘Objective: Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB), screening out and identifying the differentially expressed proteins by mass spectrometry and bioinformatics analysis, discussing the molecular mechanism of control the Diabetes deafness by GEPRB. Methods: By use of proteomics technology, the serum protein serum proteome of the control group, model control group, Duxil and each observation group were observed for 2-DE gel pattern matching, and the difference in the relative content of 2 times was chosen for the differentially expressed proteins. Identification of differentially expressed proteins by MALDI-TOF MS/MS, the authors further analysis the phosphorylation, subcellular localization, interaction, direct regulation, and transmembrane of the differences proteins by the way of bioinformatics analysis. Sixty SPF level SD rats elected in diabetic rats model group (abbreviated as DM group) were be randomly divided into 5 groups based on random number sheet, namely model control group, positive drug control group (Du-ke-xi group) and Mai-tong-fang high, medium and low dose group respectively. In addition, set of normal control group. 10 rats in each group. Results: By Coomassie brilliant blue staining, identified 51 differential protein spots dug from 2-D gel by mass spectrometry, successfully identified 13 non-redundant proteins. Most of the identified proteins were secreted protein and belong to different protein families. There were about 12 proteins have the transmembrane region from the authors’ result, ten of them were plasma membrane proteins. Conclusion: It’s suggesting that 13 differential proteins is most likely the protein response to GEPRB in vivo, these proteins may play key role for the treatment of GEPRB to Diabetes deafness. The two highly differentially expressed proteins Apolipoprotein E (apoE) and C3 may be a potential drug target of GEPRB.
基金Project supported by the National Natural Science Foundation of China.
文摘1 Introduction C<sub>60</sub> and other cage-like carbon molecules, or the fullerenes, have become one ofthe most interesting materials in physics, chemistry and materials science in recentyears. In 1985, C<sub>60</sub><sup>+</sup> ion was found to be prominent in the laser-ablation mass spec-trum of graphite and unusual stability was proposed for C<sub>60</sub> later. The discovery byKratschmer and his co-workers of a method for producing macroscopic.quantities ofC<sub>60</sub> and C<sub>70</sub> in 1990 has stimulated great interest to investigate the properties of C<sub>60</sub>and other fullerenes. Many papers have been concerned with the dissociationand stability of C<sub>60</sub> and its ions. Studies of C<sub>60</sub><sup>+</sup> dissociation by means
基金This work was supported by the State Key Fundamental R & D Project (Grant No. G1999064707)the National Natural Science Foundation of China (Grant No. 59873011) Trans-Century Training Program Foundation for the Talents by the Ministry of Education,
文摘Isolation and comparison of uremic sera and urine and normal sera and urine were performed by gel permeation chromatography, anion exchange chromatography and reversed-phase high performance liquid chromatography. Two uremic middle molecular fractions (A and B) were obtained from uremic sera and urine and normal urine by gel permeation chromatography, but not from normal sera. The anion exchange chromatographic results of fraction A from different origins demonstrate that subfraction A-3 could be excreted in urine by healthy subject, but accumulated in uremic serum for renal failure of patient with uremia. After desalinization subfraction A-3 was analyzed by MALDI-TOF-MS. The results show that subfraction A-3 consists of six compounds with molecular weight 839, 873, 1007.94, 1106, 1680 and 2015 respectively. Finally, by reversed-phase high performance liquid chromatography, subfraction A-3 was further resolved into six independent fractions. Thus, the isolation and purification of six middle molecular compounds in subfraction A-3 came true by our method.
基金supported by the National Key R&D Program of China(2017YFC0906800)the National Natural Science Foundation of China(21635006,31670373 and 21721005)
文摘20-Hydroxyecdysone(20E)derived from plants has a wide range of physiological and pharmacological ef ects on animals and humans,and rapid and sensitive methods for screening of the endogenous 20E in plants are thus required.Herein,a matrixassisted laser desorption/ionization time-of-f ight tandem mass spectrometry(MALDI-TOF/TOF MS)method is described for rapid and sensitive determination of endogenous 20E in plants.It is based on the use of the(3-(acridin-9-ylamino)phenyl)boronic acid(AYPBA)as the mass tag to assist the MS and tandem MS(MS^(n))analysis of 20E on MALDI-TOF/TOF MS.Good linearity was obtained with a determination coef cient(R^(2))larger than 0.99 in the range of 0.025–2.5μΜ.The limit of detection(LOD)was 2.4 fmol.Acceptable precision and accuracy were gained by intra-and inter-day analysis with relative standard deviations less than 19.5%and relative recoveries ranging from 85.7 to 105.2%.In addition,the AYPBA labeled 20E produced abundant characteristic fragment ions under the high energy collision-induced dissociation,which facilitated the identif cation of 20E by MS^(2)analysis on MALDI-TOF/TOF MS.Using the method,we enabled the identif cation and quantif cation of endogenous 20E in four herbs including Cyanotis arachoidea,Achyranthes bidentata,Spinacia oleracea and Chenopodium quinoa willd.,demonstrating the feasibility of the proposed method for screening of the endogenous 20E in plants.
基金This work was supported by the National Basic Research Program of China (Grant No. 2006CB300404) the National Natural Science Foundation of China (Grant Nos. 50276011, 50275026, 50475077)partly by the Natural Science Foundation of Jiangsu Province (Grant No. BK2002060).
文摘With the advantages on non-equilibrium heating and desorption induced by electronic transition, the femtosecond pulse laser introduces a new way for solving the problem of impurity pollution adsorbed on a solid thin film in micro-electro-mechanical systems (MEMS). A model based on stochastic processes was established for stimulated desorption induced by the femtosecond pulse laser to interpret the interaction of the opti-cally excited hot electrons with the adsorbed molecules in a metal substrate. Numerical simulation results reveal a time-dependent desorption probability of adsorbed molecules and indicate that how key parameters of femtosecond pulse laser, such as incident laser energy flux, pulse duration, and wavelength of pulse, have a great effect on the desorption probability.
