Microalgae are active producers of various compounds, including toxic substances. However, their metabolism is very diverse and insufficiently known. We demonstrate an approach that includes growing a new strain of cyanobacterium Leptolyngbya sp.
View Article and Find Full Text PDFIdentification of molecules in complex natural matrices relies on matching the fragmentation spectra of ions under investigation and the spectra acquired for the corresponding analytical standards. Currently, there are many databases of experimentally measured tandem mass spectrometry spectra (such as NIST, MzCloud, and Metlin), and considerable progress has been made in the development of software for predicting tandem mass spectrometry fragments in silico using combinatorial, machine learning, and quantum chemistry approaches (such as MetFrag, CFM-ID, and QCxMS). However, the electrospray ionization molecules can be ionized at different sites (protonated or deprotonated), and the fragmentation spectra of such ions are different.
View Article and Find Full Text PDFMass spectrometry has been an essential technique for the investigation of the metabolic pathways of living organisms since its appearance at the beginning of the 20th century. Due to its capability to resolve isotopically labeled species, it can be applied together with stable isotope tracers to reveal the transformation of particular biologically relevant molecules. However, low-resolution techniques, which were used for decades, had limited capabilities for untargeted metabolomics, especially when a large number of compounds are labelled simultaneously.
View Article and Find Full Text PDFThe administration of low doses of DO to living organisms was used for decades for the investigation of metabolic pathways and for the measurement of the turnover rate for specific compounds. Usually, the investigation of the deuterium uptake in lipids is performed by measuring the deuteration level of the palmitic acid residue using GC-MS instruments, and to our knowledge, the application of the modern untargeted LC-MS/MS lipidomics approaches was only reported a few times. Here, we investigated the deuterium uptake for >500 lipids for 13 organs and body liquids of mice (brain, lung, heart, liver, kidney, spleen, plasma, urine, etc.
View Article and Find Full Text PDFBackground: Sleep-disordered breathing (SDB) is highly prevalent after stroke and is considered to be a risk factor for poor post-stroke outcomes. The aim of this observational study was to evaluate the effect of nocturnal respiratory-related indices based on nocturnal respiratory polygraphy on clinical outcomes (including mortality and non-fatal events) in patients with ischemic stroke.
Methods: A total of 328 consecutive patients (181 (55%) males, mean age 65.
The identification of drug metabolites formed with different in vitro systems by HPLC-MS is a standard step in preclinical research. In vitro systems allow modeling of real metabolic pathways of a drug candidate. Despite the emergence of various software and databases, identification of compounds is still a complex task.
View Article and Find Full Text PDFIn-ESI H/D exchange is a convenient technique for analyzing small-molecular complex mixtures. However, such experiments do not yield sufficient levels of exchange or require an elevated temperature of the ion transfer capillary. Increased temperature may result in unexpected additional exchanges of -CH groups that may complicate the interpretation of the H/D exchange data used for identification.
View Article and Find Full Text PDFMono- and polysaccharides are an essential part of every biological system. Identifying underivatized carbohydrates using mass spectrometry is still a challenge because carbohydrates have a low capacity for ionization. Normally, the intensities of protonated carbohydrates are relatively low, and in order to increase the corresponding peak height, researchers add Na, K, or NHto the solution.
View Article and Find Full Text PDFDissociation induced by the accumulation of internal energy via collisions of ions with neutral molecules is one of the most important fragmentation techniques in mass spectrometry (MS), and the identification of small singly charged molecules is based mainly on the consideration of the fragmentation spectrum. Many research studies have been dedicated to the creation of databases of experimentally measured tandem mass spectrometry (MS/MS) spectra (such as MzCloud, Metlin, etc.) and developing software for predicting MS/MS fragments in silico from the molecular structure (such as MetFrag, CFM-ID, CSI:FingerID, etc.
View Article and Find Full Text PDFThe task of multipurpose analysis of biological samples and identification of individual compounds in them is actual for many organizations in various fields; the results of such analyses can affect lives. The most frequently used, most accurate, and highly sensitive method used for this kind of analysis is the combination of gas/liquid chromatography and high-resolution mass spectrometry. However, in some areas, it is necessary to increase the reliability of compound identification.
View Article and Find Full Text PDFJ Am Soc Mass Spectrom
February 2022
LC-MS is a key technique for the identification of small molecules in complex samples. Accurate mass, retention time, and fragmentation spectra from LC-MS experiments are compared to reference values for pure chemical standards. However, this information is often unavailable or insufficient, leading to an assignment to a list of candidates instead of a single hit; therefore, additional features are desired to filter candidates.
View Article and Find Full Text PDFGeorgian Med News
October 2021
Due to the steady increase in the number of patients with diabetes mellitus, as well as the development of severe complications of this pathology, the search and development of safe methods of treatment and prevention of the disease is relevant. In this direction, it seems appropriate to study the therapeutic and prophylactic properties of blueberry paste made using a unique THD-technology of the company Liqberry®. The purpose - experimental study of the anti-inflammatory properties of high-dose blueberry paste Liqberry® in a model of type 2 diabetes mellitus in laboratory Wistar rats.
View Article and Find Full Text PDFSmall molecule retention time prediction is a sophisticated task because of the wide variety of separation techniques resulting in fragmented data available for training machine learning models. Predictions are typically made with traditional machine learning methods such as support vector machine, random forest, or gradient boosting. Another approach is to use large data sets for training with a consequent projection of predictions.
View Article and Find Full Text PDFDetermination of food doneness remains a challenge for automation in the cooking industry. The complex physicochemical processes that occur during cooking require a combination of several methods for their control. Herein, we utilized an electronic nose and computer vision to check the cooking state of grilled chicken.
View Article and Find Full Text PDFRetention time is an important parameter for identification in untargeted LC-MS screening. Precise retention time prediction facilitates the annotation process and is well known for proteomics. However, the lack of available experimental information for a long time has limited the prediction accuracy for small molecules.
View Article and Find Full Text PDFVestn Khir Im I I Grek
September 2015
The article is based on the treatment results of 44 patients with follicular tunor of thyroid gland. A staged morphological assessment of thyroid nodes was performed for all patients: in case of preoperative fine-needle biopsy, urgent intraoperative study and according to results of final histological research. The urgent histological study of surgical material was conducted for 44 patients with diagnosis "follicular tumor" according to fine-needle biopsy.
View Article and Find Full Text PDFVestn Khir Im I I Grek
April 2016
The article analyzed an experience of treatment of 51 patients with follicular tumors. It was proved, that there weren't any complications and recurrences in case of typically performed operation and adequate replacement therapy in postoperative period. It was noted a good quality of life from 2 to 5 years.
View Article and Find Full Text PDFAnalysis of data on the birthplaces and ethnicity of persons who contracted marriages in the city of Donetsk in 1960, 1985, and 1992 demonstrated that the proportions of Russians and Ukrainians (the dominant ethnic groups among Donetsk residents) in the migration flow increased. The trend towards formation of ethnically disperse groups from the city residents became stronger. The index of isolation by distance (parameter b of Malecot's model) was 0.
View Article and Find Full Text PDFAnalysis of the birthplace and ethnicity of males and females contracting marriages in the city of Poltava in 1960, 1985, and 1995 revealed a trend towards return of Ukrainians from various regions of the former Soviet Union to their places of origin. In the migration flow, Russians were gradually substituted by Ukrainians, and the total proportion of Slavs increased. The isolation by distance (b) decreased from 0.
View Article and Find Full Text PDFMarriage records were used to study the dynamics of the migration flow into the population of Kharkov in 1960-1993. The decrease in the migration rate was accompanied by changes in the ethnic composition of the migrants. The entire migration flow from the republics of the Baltic region consisted of Russians and Ukrainians.
View Article and Find Full Text PDFThe results of irradiation, combined and complex treatment of pancreatic cancer have been evaluated versus stage, site and extent of surgery. Radiotherapy was carried out in 63 patients (1988-1999): prior to gastropancreaticoduodenectomy (GPDE)--7; after GPDE--12; for local recurrence after GPDE--4, before and after left-sided resection--4, before and after conservative surgery--19, and after diagnostic verification (exploratory laparotomy or ultrasound-controlled fine-needle biopsy)--17. Diagnosis was established on the basis of clinical data and case histories, ultrasonographic, CT, histological, cytological, biopsy, blood serum-marker CA 19-9 and CEA findings.
View Article and Find Full Text PDFThe investigation was concerned with diagnostic sensitivity, specificity and effectiveness of assay of CA 19-9 and carcinoembryonic antigen (CEA) in the choice of treatment modality and evaluation of therapy pancreatic carcinoma (PC). Either marker has been studied in 685 examinations for PC, 68--chronic pseudotumorous pancreatitis and 24--intestinal cancer at other sites since 1995. Tumor resection for PC was carried out in 31; conservative treatment--67; chemotherapy--56 and radiotherapy--in 29 cases.
View Article and Find Full Text PDF