Therapeutic effect and autophagy regulation of myriocin in nonalcoholic steatohepatitis.

BACKGROUND: Ceramide plays pathogenic roles in nonalcoholic fatty liver disease (NAFLD) via multiple mechanisms, and as such inhibition of ceramide de novo synthesis in the liver may be of therapeutically beneficial in patients with NAFLD. In this study, we aimed to explore whether inhibition of ceramide signaling by myriocin is beneficial in animal model of NAFLD via regulating autophagy. METHODS: Sprague Dawley rats were randomly divided into three groups: standard chow (n = 10), high-fat diet (HFD) (n = 10) or HFD combined with oral administration of myriocin (0.3 mg/kg on alternate days for 8 weeks) (n = 10). Liver histology and autophagy function were measured. HepG2 cells were incubated with fatty acid with or without myriocin treatment. Lipid accumulation and autophagy markers in the HepG2 cells were analyzed. Serum ceramide changes were studied in 104 subjects consisting healthy adults, liver biopsy-proven patients with NAFLD and liver biopsy-proven patients with chronic hepatitis B (CHB). RESULTS: Myriocin reversed the elevated body weight and serum transaminases and alleviated dyslipidemia in HFD fed rats. Myriocin treatment significantly attenuated liver pathology including steatosis, lobular inflammation and ballooning. By qPCR analysis, it was revealed that myriocin corrected the expression pattern of fatty acid metabolism associated genes including Fabp1, Pparα, Cpt-1α and Acox-2. Further, myriocin also restored the impaired hepatic autophagy function in rats with HFD-induced NASH, and this has been verified in HepG2 cells. Among the sphingolipid species that we screened in lipidomic profiles, significantly increased ceramide was observed in NASH patients as compared to the controls and non-NASH patients, regardless of whether or not they have active CHB. CONCLUSIONS: Ceramide may play an important regulatory role in the autophagy function in the pathogenesis of NASH. Hence, blockade of ceramide signaling by myriocin may be of therapeutically beneficial in NASH. TRIAL REGISTRATION: Registration ID: ChiCTR-DDT-13003983 . Data of registration: 13 May, 2013, retrospectively registered.

A Multifunctional Tb-MOF for Highly Discriminative Sensing of Eu3+ /Dy3+ and as a Catalyst Support of Ag Nanoparticles.

Exploring novel multifunctional rare earth materials is very important because these materials have fundamental interests, such as new structural facts and connecting modes, as well as potential technological applications, including optics, magnetic properties, sorption, and catalytic behaviors. Especially, employing these nanomaterials for sensing or catalytic reactions is still very challenging. Herein, a new superstable, anionic terbium-metal-organic-framework, [H2 N(CH3 )2 ][Tb(cppa)2 (H2 O)2 ], (China Three Gorges University (CTGU-1), H2 cppa = 5-(4-carboxyphenyl)picolinic acid), is successfully prepared, which can be used as a turn-on, highly-sensitive fluorescent sensor to detect Eu3+ and Dy3+ , with a detection limitation of 5 × 10-8 and 1 × 10-4 m in dimethylformamide, respectively. This result represents the first example of lanthanide-metal-organic-frameworks (Ln-MOF) that can be employed as a discriminative fluorescent probe to recognize Eu3+ and Dy3+ . In addition, through ion exchanging at room temperature, Ag(I) can be readily reduced in situ and embedded in the anionic framework, which leads to the formation of nanometal-particle@Ln-MOF composite with uniform size and distribution. The as-prepared Ag@CTGU-1 shows remarkable catalytic performance to reduce 4-nitrophenol, with a reduction rate constant κ as large as 2.57 × 10-2 s-1 ; almost the highest value among all reported noble-metal-nanoparticle@MOF composites.

Anionic Lanthanide MOFs as a Platform for Iron-Selective Sensing, Systematic Color Tuning, and Efficient Nanoparticle Catalysis.

New porous anionic Ln-MOFs, namely, [Me2NH2][Ln(CPA)2(H2O)2] (Ln = Eu, Gd), have been prepared through the self-assembly of 5-(4-carboxy phenyl)picolinic acid (H2CPA) and lanthanide ions. They feature open anionic frameworks with 1-D hydrophilic channels and exchangeable dimethylamine ions. The Eu phase could detect Fe3+ ions with high selectivity and sensitivity in either aqueous solution or biological condition. The ratios of lanthanide ions on this structure platform could be rationally tuned to not only achieve dichromatic emission colors with linear correlation but also attain three primary colors (RGB) and even white light with favorable correlated color temperature. Furthermore, the Ag(I)-exchanged phases can be readily reduced to afford Ag nanoparticles. The as-prepared Ag@Ln-MOFs composite shows highly efficient catalytic performance for the reduction of 4-nitrophenol.

[Study on mechanism of combined administration of Coptidis Rhizoma and Rehmanniae Radix in treating type II diabetes mellitus].

To make a preliminary study on the mechanism of Coptidis Rhizoma(CR) and Rehmanniae Radix(RR) before and after the combined administration in treating type II diabetes mellitus. The type I diabetes animal model in rats was established by fat emulsion and intraperitoneal injection with streptozotocin, in order to compare the hpyerglycemic and hypolipidemic effects of CR, RR and their combined administration of different ratio. The urinary metabolic profiling in rats of Coptidis Rhizoma and Rehmanniae Radix before and after the combined administration was analyzed by using the gas chromatography-mass spectrometry. The differences among groups in metabolome were analyzed by the principal component analysis (PCA). The biochemical index results indicated that both CR and RR before and after the combined administration could lower high blood glucose, hypertriglyceride and high cholesterol. According to the analytical results of PCA of the rats' urine samples, the CR group was the most close to the normal group, with no significant difference in CR and RR group of different combination ratios. Twelve differentiated metabolites were identified to be related to type II diabetes. Compared with the normal group, the CR-treated group showed significant increase in seven differentiated metabolites. Among CR and RR drugs with different combination ratios, CR played a major role and thus acted as the monarch drug. Whereas RR served as the ministerial drug and assisted CR to show the efficacy. This study laid a foundation for the explanation of the combination mechanism of traditional Chinese medicines.

[Research progress of deep learning applications in mass spectrometry imaging data analysis].

Mass spectrometry imaging (MSI) is a promising method for characterizing the spatial distribution of compounds. Given the diversified development of acquisition methods and continuous improvements in the sensitivity of this technology, both the total amount of generated data and complexity of analysis have exponentially increased, rendering increasing challenges of data postprocessing, such as large amounts of noise, background signal interferences, as well as image registration deviations caused by sample position changes and scan deviations, and etc. Deep learning (DL) is a powerful tool widely used in data analysis and image reconstruction. This tool enables the automatic feature extraction of data by building and training a neural network model, and achieves comprehensive and in-depth analysis of target data through transfer learning, which has great potential for MSI data analysis. This paper reviews the current research status, application progress and challenges of DL in MSI data analysis, focusing on four core stages: data preprocessing, image reconstruction, cluster analysis, and multimodal fusion. The application of a combination of DL and mass spectrometry imaging in the study of tumor diagnosis and subtype classification is also illustrated. This review also discusses trends of development in the future, aiming to promote a better combination of artificial intelligence and mass spectrometry technology.

[New advances in exposomics-analysis methods and research paradigms based on chromatography-mass spectrometry].

The occurrence and development of human diseases are influenced by both genetic and environmental factors. Research models that describe disease occurrence only from the perspective of genetics present certain limitations. In recent years, effects of environment factors on the occurrence and development of diseases have attracted extensive attentions. Exposomics focuses on the measurement of all exposure factors in an individual's life and how these factors are related to disease development. Exposomics provides new ideas to promote studies on the relationship between human health and environmental factors. Environmental exposures are characterized with different physical and chemical properties, as well as very low concentrations in vivo, which contribute great challenges in the comprehensive measurement of chemical residues in the human body. Chromatography-mass spectrometry-based technologies combine the high-efficiency separation ability of chromatography with the high resolution and sensitive detection characteristics of mass spectrometry; the combination of these techniques can achieve the high-coverage, high-throughput, and sensitive detection of environmental exposures, thus providing a powerful tool for measuring chemical exposures. Exposomics-analysis methods based on chromatography-mass spectrometry mainly include targeted quantitative analysis, suspect screening, and non-targeted screening. To explore the relationship between environmental exposure and the occurrence and development of diseases, researchers have developed research paradigms, including exposome wide association study, mixed-exposure study, exposomics and multi-omics (genome, transcriptome, proteome, metabolome)-association study, and so on. The emergence of these methods has brought about unprecedented developments in exposomics studies. In this manuscript, analytical methods based on chromatography-mass spectrometry, exposomics research paradigms, and their relevant prospects are reviewed.

[Risk analysis of serum chemical residues for metabolic associated fatty liver disease based on exposome-lipidome wide association study].

Metabolic associated fatty liver disease (MAFLD) is a common liver disease with a prevalence of up to 25%; it not only adversely affects human health but also aggravates the economic burden of society. An increasing number of studies have suggested that the occurrence of chronic noncommunicable diseases is affected by both environmental exposures and genetic factors. Research has also shown that environmental pollution may increase the risk of MAFLD and promote its occurrence and development. However, the relationship between these concepts, as well as the underlying exposure effects and mechanism, remains incompletely understood. Lipidomics, a branch of metabolomics that studies lipid disorders, can help researchers investigate abnormal lipid metabolites in various disease states. Lipidome-exposome wide association studies are a promising paradigm for investigating the health effects of cumulative environmental exposures on biological responses, and could provide new ideas for determining the associations between metabolic and lipid changes and disease risk caused by chemical-pollutant exposure. Hence, in this study, targeted exposomics and nontargeted lipidomics studies based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) were used to characterize exogenous chemical pollutants and endogenous lipid metabolites in the sera of patients with MAFLD and healthy subjects. The results demonstrated that fipronil sulfone, malathion dicarboxylic acid, and monocyclohexyl phthalate may be positively associated with the disease risk of patients diagnosed as simple fatty liver disease (hereafter referred to as MAFLD(0)). Moreover, fipronil sulfone, acesulfame potassium, perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUnDA), 4-hydroxybenzophenone, and 3,5-di-tert-butyl-4-hydroxybenzoic acid (DBPOB) may be positively associated with the disease risk of patients diagnosed as fatty liver complicated by single or multiple metabolic disorders. Association analysis was carried out to explore the lipid metabolites induced by chemical residues. Triglyceride (TG) and diglyceride (DG) were significantly increased in MAFLD and MAFLD(0). The numbers of carbons of significantly changed DGs and TGs were mainly in the ranges of 32-40 and 35-60, respectively, and both were mainly characterized by changes in polyunsaturated lipids. Most of the lipid-effect markers were positively correlated with chemical residues and associated with increased disease risk. Our research provides a scientific basis for studies on the association and mechanism between serum chemical-pollutant residues and disease outcomes.

Interplay between dietary intake, gut microbiota, and metabolic profile in obese adolescents: Sex-dependent differential patterns.

BACKGROUND & AIMS: The interplay among dietary intake, gut microbiota, gut metabolites and circulating metabolites in adolescents is barely known, not to mention sex-dependent pattern. We aimed to explore unique profiles of gut bacterial, gut metabolites and circulating metabolites from both genders of adolescents due to BMI and eating pattern. METHODS: Clinical indices, fecal gut microbiota, fecal and plasma metabolites, and diet intake information were collected in case-control sample matched for normal and obesity in girls (normal = 12, obesity = 12) and boys (normal = 20, obesity = 20), respectively. 16S rRNA gene sequencing and untargeted metabolomics was performed to analysis the signature of gut microbiota and metabolites. Unique profiles of girls associated with BMI and eating pattern was revealed by Spearman's correlations analysis, co-occurrence network analysis, Kruskal-Wallis test, and Wilcoxon rank-sum test. RESULTS: Gender difference was found between normal and obese adolescents in gut microbiota, fecal metabolites, and plasma metabolites. The Parabacteroides were only decreased in obese girls. And the characteristic of obese girls' and boys' cases in fecal and plasma was xanthine and glutamine, ornithine and LCA, respectively. Soy products intake was negatively associated with Parabacteroides. The predicted model has a higher accuracy based on the combined markers in obesity boys (AUC = 0.97) and girls (AUC = 0.97), respectively. CONCLUSIONS: Reduced abundance of Phascolarctobacterium and Parabacteroides, as well as the increased fecal xanthine and ornithine, may provide a novel biomarker signature in obesity girls and boys. Soy products intake was positively and negatively associated with Romboutsia and Parabacteroides abundance, respectively. And the combined markers facilitate the accuracy of predicting obesity in girls and boys in advance.

Metabolic Profiling Reveals Biochemical Pathways and Potential Biomarkers of Spinocerebellar Ataxia 3.

Spinocerebellar ataxia 3, also known as Machado-Joseph disease (SCA3/MJD), is a rare autosomal-dominant neurodegenerative disease caused by an abnormal expansion of CAG repeats in the ATXN3 gene. In the present study, we performed a global metabolomic analysis to identify pathogenic biochemical pathways and novel biomarkers implicated in SCA3 patients. Metabolic profiling of serum samples from 13 preclinical SCA3 patients, 13 symptomatic SCA3 patients, and 15 healthy controls were mapped using ultra-high-performance liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry techniques. The symptomatic SCA3 patients showed a metabolic profile significantly distinct from those of the preclinical SCA3 patients and healthy controls. The principal differential metabolites were involved in the amino acid (AA) metabolism and fatty acid metabolism pathways. In addition, four candidate serum biomarkers, FFA 16:1 (palmitoleic acid), FFA 18:3 (linolenic acid), L-Proline and L-Tryptophan, were selected to discriminate between symptomatic SCA3 patients and healthy controls by receiver operator curve analysis with an area under the curve of 0.979. Our study demonstrates that symptomatic SCA3 patients present distinct metabolic profiles with perturbed AA metabolism and fatty acid metabolism, and FFA 16:1, FFA 18:3, L-Proline and L-Tryptophan are identified as potential disease biomarkers.

[Recent advances in metabonomics].

Metabonomics (or metabolomics) aims at the comprehensive and quantitative analysis of the wide arrays of metabolites in biological samples. Metabonomics has been labeled as one of the new" -omics" joining genomics, transcriptomics, and proteomics as a science employed toward the understanding of global systems biology. It has been widely applied in many research areas including drug toxicology, biomarker discovery, functional genomics, and molecular pathology etc. The comprehensive analysis of the metabonome is particularly challenging due to the diverse chemical natures of metabolites. Metabonomics investigations require special approaches for sample preparation, data-rich analytical chemical measurements, and information mining. The outputs from a metabonomics study allow sample classification, biomarker discovery, and interpretation of the reasons for classification information. This review focuses on the currently new advances in various technical platforms of metabonomics and its applications in drug discovery and development, disease biomarker identification, plant and microbe related fields.

[Assessment of therapeutic effect of losartan on diabetes mellitus with gas chromatography-based metabonomics].

OBJECTIVE: To assess the therapeutic effect of losartan on type 2 diabetes mellitus (DM2) with gas chromatography (GC)-based metabonomics. METHODS: DM2 patients were dosed with losartan (100 mg/d) and urines were collected at week 8 and 12. The biochemical criteria (blood pressure, urinary albumen, urinary 8-hydroxy-2'-deoxyguanosine and blood creatinine) were analyzed. Urine samples were derivatived and analyzed by GC. Multivariate metabonomics analysis was performed after peak alignment. RESULTS: After 8-12 weeks, losartan showed little curative effect and no remarked changes of biochemical criteria were observed. However, metabonomics analysis revealed that some biomarkers such as glucitol and inositol changed. CONCLUSION: GC-based metabonomics analysis enables the rapid identification of metabolic differences and provides information concerning therapeutic effect of losartan.

[Lung cancer diagnosis based on urinary modified nucleoside metabolic profiling].

OBJECTIVE: To study the feasibility of modified urinary nucleosides metabolic profiling on lung cancer diagnoses. METHODS: The modified urinary nucleosides metabolic profiling from 42 normal adults and 80 patients with lung cancer were determined by a coupled-column high performance liquid chromatography system. Partial least squares-discriminant analysis (PLS-DA) models were used to class differentiation between the lung cancer patients and controls and to discover potential biomarkers. RESULT: The PLS-DA model results showed that there was a clear differentiation between normal adults and lung cancers patients, with the value of prediction (Q2) equals to 0.744. CONCLUSION: Modified urinary nucleosides metabolic profiling method is useful for lung cancer diagnoses.

[Microbial diversity in shengli petroleum reservoirs analyzed by T-RFLP].

Recent investigations on the microbial ecology of oil reservoirs in a variety of locales indicated that these habitats harbor various assemblages. In this study, a cultured-independent molecular technique, Terminal Restriction Fragment Length Polymorphism (T-RFLP), was used to analyze the microbial diversity of an injection well (S12-ZHU) and three related production wells (S12-4, S12-5 and S12-19) in the ShengLi oilfield (Shandong province, China). The 16S rRNA genes were amplified by PCR with the 5'carboxy-fluorescein (5-FAM)-labelled universal forward primers (27F for bacteria and 21F for archaea) and a universal reverse primer (1495R). Then the 16S rRNA genes were digested with restriction enzymes (Hae III and Hha I) and analyzed by using an automated DNA sequencer. The Shannon-Wiener Diversity index, based on the T-RFLP profiles, indicated that the bacterial and archaeal species richness in the injection well was higher than those of the production ones. The similarity coefficient showed the microbial community similarity among the four samples was 22.4%-30.8% (Bacteria) and 20.8%-34.5% (Archaea), respectively. According to the analysis by TAP T-RFLP program, species belonging to Pseudomonas, Marinobacter and Methanosarcina as well as some uncultured archaeon were supposed to be the dominant bacteria in all four samples. Thus, this study indicates that T-RFLP is useful for analysis of the microbial diversity in petroleum reservoirs.

[Separation and determination of oleanolic acid and ursolic acid from Cornus officinalis by capillary electrophoresis].

A cycledextrin-modified micellar electrokinetic chromatography technique for separating and determination oleanolic acid and ursolic acid in the fruit of Cornus officinalis was developed. The two bio-active components was completely separated using a buffer containing 60 mmol/L SDS, 2.5 mmol/L NaH2PO4, 2.5 mmol/L Na2B4O7, 8 mmol/L DM beta-CD,8 mmol/L beta-CD and 30% (v/v) 2-propanol. The correlation cofficients of the linear calibration graphs for oleanolic acid and ursolic acid are 0. 9996 and 0.9995, respectively. The effects of SDS, 2-propanol, dimethyl-beta-cyclodextrin, beta-cyclodextrin, NaH2PO4, Na2B4O7 and pH on separation were investigated.

Serum Monounsaturated Triacylglycerol Predicts Steatohepatitis in Patients with Non-alcoholic Fatty Liver Disease and Chronic Hepatitis B.

Chronic liver disease is associated with lipid metabolic disruption. We carried out a study to determine serum lipidomic features of patients with non-alcoholic fatty liver disease (NAFLD) and active chronic hepatitis B (CHB) and explored the biomarkers for non-alcoholic steatohepatitis (NASH). Serum lipidomic profiles of healthy controls (n = 23) and of biopsy-proven NAFLD (n = 42), CHB with NAFLD (n = 22) and without NAFLD (n = 17) were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. There were distinct serum lipidome between groups of NAFLD and CHB without NAFLD. Most of the neutral lipids and ceramide were elevated in the NAFLD group but were decreased in the CHB without NAFLD group. Plasmalogens were decreased in both groups. Triacylglycerols (TAGs) with lower carbon numbers and double bonds were increased in subjects with NASH. Serum monounsaturated TAG was a significant predictor of NASH (OR = 3.215; 95%CI 1.663-6.331) and positively correlated with histological activity (r = 0.501; P < 0.001). It showed good predictability for NASH in the NAFLD group [area under the receiver operating characteristic curves (AUROC) = 0.831] and was validated in the CHB group (AUROC = 0.833); this characteristic was superior to that of cytokeratin-18 and alanine transaminase. The increase in monounsaturated TAG might be a specific marker for NASH in both NAFLD and CHB patients.

Clinical significance and prognostic value of urinary nucleosides in breast cancer patients.

OBJECTIVE: Thirteen urinary nucleosides, primarily degradation products of tRNA, were evaluated as potential tumor markers for breast cancer patients. DESIGN AND METHODS: The micellar electrokinetic chromatography (MEKC) method has been used to analyze the urinary nucleosides in 41 healthy controls, 20 patients with benign breast tumors, and 26 breast cancer patients. RESULTS: Urinary nucleoside concentrations of breast cancer patients were found to increase significantly compared to those of patients with benign breast tumors and healthy controls. By using 13 nucleoside concentrations as data vectors for principal component analysis (PCA), 73% (19/26) of breast cancer patients were correctly identified from healthy controls, while only 20% (4/20) of patients with benign breast tumors were indistinguishable from breast cancer patients. The mean level of all forms of urinary nucleosides in patients with metastatic breast cancer was higher than that in patients with primary breast cancer. The levels of modified nucleosides tended to decrease and return to normal after surgery. CONCLUSION: The results indicate that urinary nucleosides may be useful as tumor markers for breast cancer.

Effect of Helicobacter pylori infection on p53 expression of gastric mucosa and adenocarcinoma with microsatellite instability.

AIM: To investigate the relationship between Helicobacter pylori (H pylori) infection, microsatellite instability and the expressions of the p53 in gastritis, intestinal metaplasia and gastric adenocarcinoma and to elucidate the mechanism of gastric carcinogenesis relating to H pylori infection. METHODS: One hundred and eight endoscopic biopsies and gastric adenocarcinoma were available for the study including 33 cases of normal, 45 cases of gastritis, 30 cases of intestinal metaplasia, and 46 cases of gastric adenocarcinoma. Peripheral blood samples of these patients were also collected. H pylori infection and p53 expressions were detected by means of streptavidin-peroxidase (SP) immunohistochemical method. Microsatellite loci were studied by PCR-SSCP-CE using the markers BAT-26, D17S261, D3S1283, D2S123, and D3S1611. MSI was defined as the peak shift in the DNA of the gastric tissue compared with that of the peripheral blood samples. Based on the number of mutated MSI markers, specimens were characterized as high MSI (MSI-H) if they manifested instability at two or more markers, low MSI (MSI-L) if unstable at only one marker, and microsatellite stable (MSS) if they showed no instability at any marker. RESULTS: H pylori infection was detected in the samples of gastritis, intestinal metaplasia, and gastric adenocarcinoma and the infection frequencies were 84.4%, 76.7%, and 65.2%, respectively, whereas no H pylori infection was detected in the samples of normal control. There was a significant difference in the infection rates between gastritis and carcinoma samples (P = 0.035). No MSI was detected in gastritis samples, one MSI-H and two MSI-L were detected among the 30 intestinal metaplasia samples, and 12 MSI-H and 3 MSI-L were detected in the 46 gastric carcinomas. In those gastric carcinomas, the MSI-H frequency in H pylori-positive group was significantly higher than that in H pylori-negative group. No p53 expression was detected in the normal and gastritis samples from dyspeptic patients. P53-positive immunohistochemical staining was detected in 13.3% of intestinal metaplasia samples and in 43.5% of gastric carcinoma samples. The levels of p53 in H pylori-positive samples were higher than those in the negative group when the carcinoma samples were subdivided into H pylori-positive and -negative groups (P = 0.013). Eight samples were detected with positive p53 expression out of the 11 MSI-H carcinomas with H pylori infection and no p53 expression could be seen in the H pylori-negative samples. CONCLUSION: H pylori affect the p53 pattern in gastric mucosa when MMR system fails to work. Mutations of the p53 gene seem to be an early event in gastric carcinogenesis.

Urinary nucleosides as biological markers for patients with colorectal cancer.

AIM: Fourteen urinary nucleosides, primary degradation products of tRNA, were evaluated to know the potential as biological markers for patients with colorectal cancer. METHODS: The concentrations of 14 kinds of urinary nucleosides from 52 patients with colorectal cancer, 10 patients with intestinal villous adenoma and 60 healthy adults were determined by column switching high performance liquid chromatography method. RESULTS: The mean levels of 12 kinds of urinary nucleosides (except uridine and guanosine) in the patients with colorectal cancer were significantly higher than those in patients with intestinal villous adenoma or the healthy adults. Using the levels of 14 kinds of urinary nucleosides as the data vectors for principal component analysis, 71% (37/52) patients with colorectal cancer were correctly classified from healthy adults, in which the identification rate was much higher than that of CEA method (29%). Only 10% (1/10) of patients with intestinal villous adenoma were indistinguishable from patients with colorectal cancer. The levels of m1G, Pseu and m1A were positively related with tumor size and Duke's stages of colorectal cancer. When monitoring the changes in urinary nucleoside concentrations of patients with colorectal cancer associated with surgery, it was found that the overall correlations with clinical assessment were 84% (27/32) and 91% (10/11) in response group and progressive group, respectively. CONCLUSION: These findings indicate that urinary nucleosides determined by column switching high performance liquid chromatography method may be useful as biological markers for colorectal cancer.

HMLH1 gene mutation in gastric cancer patients and their kindred.

AIM: To study the status of hMLH1 gene point mutations of gastric cancer kindreds and gastric cancer patients from northern China, and to find out gene mutation status in the population susceptible to gastric cancer. METHODS: Blood samples of 120 members from five gastric cancer families, 56 sporadic gastric cancer patients and control individuals were collected. After DNA extraction, the mutations of exon 8 and exon 12 of hMLH1 gene were investigated by PCR-SSCP-CE, followed by DNA sequencing. RESULTS: In the five kindreds, the mutation frequency was 25% (5/16) for the probands and 18% (19/104) for the non-cancerous members, which were significantly higher than the controls (P<0.01 chi2 = 7.71, P<0.01 chi2 = 8.65, respectively). In the sporadic gastric cancer, the mutation frequency was 7% (4/56), which was similar to that (5/100) in the healthy controls. The mutation point of exon 8 was at 219 codon of hMLH1 gene (A-G), resulting in a substitution of Ile-Val (ATC-GTC), whereas the mutation of exon 12 was at 384 codon of hMLH1 gene (T-A) resulting in a substitution of Asp-Val (GTT-GAT), which were the same as previously found in hereditary nonpolyposis colorectal carcinoma. CONCLUSION: The members of gastric cancer families from northern China may have similar genetic background of hMLH1 gene mutation as those of hereditary nonpolyposis colorectal carcinoma.