BIOMARKERS INDICATING SEDIMENTARY PALEOENVIRONMENTS

Samples involved in this paper are 35 pieces of crude oils and 43 pieces of source rocks, from which a series of biomarkers, capable of indicating paleoecology and paleoenvironment. This will provide a scientific basis for tracing back to sedimenta-y paleoenvironment and paleoecology.     

Structural characterization of lipopeptide biomarkers isolated from Bacillus globigii

Spectra obtained using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry of Bacillus globigii (Bacillus subtilis niger) spores, vegetative cells and the culture supernatant show a cluster of biomarkers centered at a molecular mass of 1478 Da. Three biomarkers were isolated from the cell-free culture supernatant by solid-phase extraction and reversed-phase high-performance liquid chromatography, and characterized using various kinds of mass spectrometry. A Fourier transform mass spectrometer with a MALDI source was used to determine the monoisotopic protonated masses at 1463.8, 1477.8, and 1505.8 Da in order of elution. The mass differences of 14 and 28 Da suggest that they are homologous molecules. Alkaline hydrolysis of each species showed that it contained a lactone linkage. Strong acid hydrolysis released a fatty acid from an amide bond, consistent with a lipopeptide. A quadrupole time-of-flight instrument with a nanospray source was used to sequence the hydrolyzed forms of the three biomarkers. The cyclic lipopeptides were found to have amino acid sequences identical with those in fengycins and plipastatins, antimicrobial compounds with phospholipase inhibitor activity, previously identified in related species of Bacillus subtilis and Bacillus cereus.     

口腔癌相关唾液肿瘤生物标志物的分析检测研究进展

口腔癌系头颈部癌，癌组织均位于口腔内，其非侵入性早期诊断是减少该病死亡的有效手段.唾液系口腔癌变相关物质首先释放进入的体液，取材方便，安全无创，是口腔癌普查筛选、早期诊断的首选指标.本文对唾液肿瘤生物标志物的种类、目前国内外常用的检测方法进行概述，重点阐述新型电化学生物传感方法在口腔癌相关唾液肿瘤生物标志物检测方面的相关应用及其最新研究进展.并对口腔癌相关唾液肿瘤生物标志物电化学传感技术的未来发展方向提出展望，拟为其深入研究与应用提供参考.     

Screening of exon methylation biomarkers for colorectal cancer via LC‐MS/MS strategy

The identification of biomarkers would be of benefit for the diagnosis and treatment of colorectal cancer. DNA methylation in specific genomic regions, which had shown strongly association with disease genotypes, was an effective indicator to reveal the occurrence and development of cancers. To screen out methylation biomarkers for colorectal cancer (CRC), genomic DNA was isolated from colorectal cancerous and corresponding cancer‐adjacent tissues collected from 30 CRC patients and then bisulfite‐converted. The exon regions of 5 targeted genes (CNRIP1 , HIC1 , RUNX3 , p15 , and SFRP2 ) were amplified by using nested polymerase chain reaction with specific primers, and the amplicon was purified and hydrolyzed. The methylation levels of these specific regions were detected by liquid chromatography tandem mass spectrometry (LC‐MS/MS). The results showed that 5 targeted exon regions were successfully amplified and confirmed by sequencing. The methodological validations indicated that LC‐MS/MS was highly sensitive and accurate. The methylation levels of CNRIP1 and RUNX3 were remarkably high in CRC tissues with statistical difference when compared with corresponding cancer‐adjacent individuals, while that of HIC1 , p15 , and SFRP2 had no difference between 2 subjects. These findings supported CNRIP1 and RUNX3 as potential DNA methylation biomarkers for CRC diagnosis and treatment, and our LC‐MS/MS approach exhibited great advantages in the identification of regional DNA methylation biomarkers.     

Early detection of viral DNA in breast cancer using fingered aluminium interdigitated electrode modified by Streptavidin-biotin tetravalent complex

Human Mammary Tumor Virus (HMTV) or Mouse Mammary Tumor Virus holds similarity as an endogenous onco-retrovirus belongs to retroviridae family, predominantly infects the epithelial cell of human as well as mouse. With the recognition of nano-biosensor in nanotechnology, ideal interdigitated electrode (IDE) was genuinely performed for HMTV detection. Aluminium enriched IDE (AlIDE) was fabricated for high performance detection with a cost-effective photolithography technique. In this research, (3-glycidyloxypropyl) trimethoxysilane refined platform was selected to detect the conductivity with HMTV target DNA interaction on the designed AlIDE. Strong binding affinity of streptavidin-biotin with target DNA enhanced the sensitivity by empowering higher number of HMTV probe and target complementation on sensing surface. Furthermore, the target DNA was immobilized on probe modified AlIDE and a quantitative value of 100 aM attained as a lowest detection. A linear with dose-dependent duplex formation was shown with the regression coefficient value of 0.964. Negative control has shown insignificant detection at 10 pM, which justifies the higher fold discrimination with specificity. The excellence of AlIDE performance in detection of HMTV may pave the way for more verification on other diseases.     

Quantification of Volatile Aldehydes Deriving from In Vitro Lipid Peroxidation in the Breath of Ventilated Patients

Exhaled aliphatic aldehydes were proposed as non-invasive biomarkers to detect increased lipid peroxidation in various diseases. As a prelude to clinical application of the multicapillary column–ion mobility spectrometry for the evaluation of aldehyde exhalation, we, therefore: (1) identified the most abundant volatile aliphatic aldehydes originating from in vitro oxidation of various polyunsaturated fatty acids; (2) evaluated emittance of aldehydes from plastic parts of the breathing circuit; (3) conducted a pilot study for in vivo quantification of exhaled aldehydes in mechanically ventilated patients. Pentanal, hexanal, heptanal, and nonanal were quantifiable in the headspace of oxidizing polyunsaturated fatty acids, with pentanal and hexanal predominating. Plastic parts of the breathing circuit emitted hexanal, octanal, nonanal, and decanal, whereby nonanal and decanal were ubiquitous and pentanal or heptanal not being detected. Only pentanal was quantifiable in breath of mechanically ventilated surgical patients with a mean exhaled concentration of 13 ± 5 ppb. An explorative analysis suggested that pentanal exhalation is associated with mechanical power—a measure for the invasiveness of mechanical ventilation. In conclusion, exhaled pentanal is a promising non-invasive biomarker for lipid peroxidation inducing pathologies, and should be evaluated in future clinical studies, particularly for detection of lung injury.     

Database-assisted global metabolomics profiling of pleural effusion induced by tuberculosis and malignancy

Database-assisted global metabolomics has received growing attention due to its capability for unbiased identification of metabolites in various biological samples. Herein, we established a mass spectrometry (MS)-based database-assisted global metabolomics method and investigated metabolic distance between pleural effusion induced by tuberculosis and malignancy, which are difficult to be distinguished due to their similar clinical symptoms. The present method utilized a liquid chromatography (LC) system coupled with high resolution mass spectrometry (MS) working on full scan and data dependent mode for data acquisition. Unbiased identification of metabolites was performed through mass spectral searching and then confirmed by using authentic standards. As a result, a total of 194 endogenous metabolites were identified and 33 metabolites were found to be differentiated between tuberculous and malignant pleural effusions. These metabolites involved in tryptophan catabolism, bile acid biosynthesis, and β-oxidation of fatty acids, provided non-invasive biomarkers for differentiation of the pleural effusion samples with high sensitivity and specificity.     

Specific Recognition of β-Galactofuranose-Containing Glycans of Synthetic Neoglycoproteins by Sera of Chronic Chagas Disease Patients

Chagas disease (CD) can be accurately diagnosed by detecting Trypanosoma cruzi in patients’ blood using polymerase chain reaction (PCR). However, parasite-derived biomarkers are of great interest for the serological diagnosis and early evaluation of chemotherapeutic efficacy when PCR may fail, owing to a blood parasite load below the method’s limit of detection. Previously, we focused on the detection of specific anti-α-galactopyranosyl (α-Gal) antibodies in chronic CD (CCD) patients elicited by α-Gal glycotopes copiously expressed on insect-derived and mammal-dwelling infective parasite stages. Nevertheless, these stages also abundantly express cell surface glycosylphosphatidylinositol (GPI)-anchored glycoproteins and glycoinositolphospholipids (GIPLs) bearing nonreducing terminal β-galactofuranosyl (β-Galf) residues, which are equally foreign to humans and, therefore, highly immunogenic. Here we report that CCD patients’ sera react specifically with synthetic β-Galf-containing glycans. We took a reversed immunoglycomics approach that entailed: (a) Synthesis of T. cruzi GIPL-derived Galfβ1,3Manpα-(CH₂)₃SH (glycan G29_SH) and Galfβ1,3Manpα1,2-[Galfβ1,3]Manpα-(CH₂)₃SH (glycan G32_SH); and (b) preparation of neoglycoproteins NGP29b and NGP32b, and their evaluation in a chemiluminescent immunoassay. Receiver-operating characteristic analysis revealed that NGP32b can distinguish CCD sera from sera of healthy individuals with 85.3% sensitivity and 100% specificity. This suggests that Galfβ1,3Manpα1,2-[Galfβ1,3]Manpα is an immunodominant glycotope and that NGP32b could potentially be used as a novel CCD biomarker.     

Copper and Zinc as Potential Biomarkers of Mood Disorders and Pandemic Syndrome

The diagnosis of affective disorders has been the subject of constant research by clinicians from all over the world for many years. Making an appropriate diagnosis among patients suffering from mood disorders is sometimes problematic due to the personality-changing nature of patients and the similarity in the clinical picture of episodes in affective disorders. For this reason, there is a need to develop rapid and effective methods of determining biological markers that differentiate these diseases. The research was carried out with blood taken from 15 patients and 15 volunteers. The analysis of biological material for trace concentrations of zinc and copper was carried out with the use of ultrasensitive triple-quadrupole inductively coupled plasma mass spectrometry (TQ ICP-MS). The obtained results prove that the concentration of copper in the test group was lower than in the control group. For the zinc concentrations, the inverse relationship was observed. The group of patients was characterized by a higher concentration of this element than the group of healthy volunteers. Summarizing the obtained results and comparing them with the results of studies by other authors, it was found that zinc and copper may be potential biomarkers of affective disorders and pandemic syndrome.