Mass Spectrometry Research Articles

Simultaneous Analysis of Imidazole Dipeptides, Constituent Amino Acids, and Taurine in Meats Using the Highly Sensitive Labeling Reagent l-FDVDA and PBr Column.

Imidazole dipeptides (IDPs) are found in the skeletal muscles and brains of various animals, and they exhibit unique functions like antioxidant and antiaging properties. Despite their importance, the metabolic mechanisms and physiological roles of IDPs remain unclear. Herein, we propose a method for the simultaneous analysis of IDPs, their constituent amino acids, and taurine, which are difficult to separate using conventional labeling reagents or columns, using liquid chromatography-single quadrupole mass spectrometry with PBr column and our highly sensitive labeling reagent, 1-fluoro-2,4-dinitrophenyl-5-l-valine-N,N-dimethylethylenediamineamide (l-FDVDA). This method successfully separated histidine and carnosine enantiomers as well as l-2-oxocarnosine with high antioxidant activity under the same conditions. Our labeling reagent was more stable than the other reagents and did not degrade and desorb from the analytes for at least 1 week at 4 °C. Furthermore, our method allows for the accurate analysis of IDPs, amino acids, and taurine in meats from various animal species, tissues, and breeds.

Causes, influencing factors, and prediction modeling of crystallization blockage of tunnel drainage blind pipe in non-karst area

The complete functioning of the tunnel drainage system is critical in ensuring the stability of tunnel lining structures and safe operations. Therefore, the issue of crystalline blockage in the tunnel drainage system needs to be solved urgently. In this study, the formation mechanism of tunnel crystallization defects in non-karst areas was investigated, and the influencing factors of calcium ion dissolution of shotcrete were evaluated by field investigation. Also, the sampling analysis was carried out to determine the ionic composition and content of seepage water. The source and composition of crystallites were determined by X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), and field-emission scanning electron microscope (SEM). The mechanism and role of pH in CaCO3 crystal formation were explored by simulation using MINTEQ 3.1 software. In addition, a new accelerated leaching test model was developed to examine the flow rate, concentration, and temperature effects on Ca2+ leaching rate in shotcrete. The analysis of water quality and crystal showed that the white and yellow crystals in the tunnel were calcite-type calcium carbonate, occurring as a paste. Micro-morphology of new crystals showed densely-distributed prismatic spherical and scaly crystal structure. The other parts were irregular squares, spindles, rhombuses, and other forms of scattered distribution. The Ca2+ originated from the shotcrete. The accelerated leaching test demonstrated that the optimal test conditions for the leaching rate of Ca2+ in shotcrete were a flow rate of 4 L/min, concentration of 5 mol/L, and temperature of 20 °C. Based on these findings, the prediction model of the Ca2+ leaching rate of shotcrete is established.

Alternate Sampling Matrices for Therapeutic Drug Monitoring of Immunosuppressants.

Immunosuppressant (IS) therapeutic drug monitoring (TDM) relies on measuring mostly pharmacologically inactive erythrocyte-bound and/or plasma protein-bound drug levels. Variations in hematocrit and plasma protein levels complicate interpretation of blood calcineurin inhibitor (CNI) and inhibitors of themolecular target of rapamycin (mTORi) concentrations. Variable binding of mycophenolic acid (MPA) to albumin similarly complicates its TDM in plasma. A different matrix may improve IS concentration-response relationships and better reflect exposures at sites of action. This review explores the evidence for IS TDM using peripheral blood mononuclear cell (PBMC), graft tissue, and total or unbound plasma concentrations. Tandem mass spectrometry provides the sensitivity for assessing these matrices. But several challenges must be addressed, including minimizing hemolysis during blood collection, preventing IS efflux during PBMC preparation, and determining the need for further purification of the PBMC fraction. Assessing and reducing nonspecific binding during separation of unbound IS are also necessary, especially for lipophilic CNIs/mTORi. Although TDM using PBMC or unbound plasma concentrations may not be feasible due to increased costs, plasma CNI/mTORi levels may be more easily integrated into routine TDM. However, no validated TDM targets currently exist, and published models to adjust blood CNI/mTORi concentrations for hematocrit or to predict PBMC, and total and unbound plasma IS concentrations have yet to be validated in terms of measured concentrations or prediction of clinical outcomes. Even if CNI/mTORi measurements in novel matrices do not become routine, they may help refine pharmacokinetic-pharmacodynamic relationships and improve mathematical models for TDM using whole blood. Notably, there is evidence to support measuring unbound MPA in patients with severe renal dysfunction, hypoalbuminemia, and hyperbilirubinemia, with some proposed TDM targets.

The miR-1269a/PCDHGA9/CXCR4/β-catenin pathway promotes colorectal cancer invasion and metastasis.

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related death. This research focuses on investigating the impact and underlying molecular mechanisms of protocadherin gamma subfamily A, 9 (PCDHGA9) on the invasion and metastasis of CRC, aiming to identify more precise molecular markers for the diagnosis and prognosis of CRC. PCDHGA9 expression was detected using quantitative real-time quantitative polymerase chain reaction (RT-qPCR) in 63 pairs of colorectal cancer tissues. Differential gene expression from high-throughput sequencing was analyzed using ingenuity pathway analysis (IPA) to explore the biological functions of PCDHGA9 and its potential regulated genes. Bioinformatics tools were employed to explore potential upstream regulatory microRNAs of PCDHGA9. Dual-luciferase assays were performed to demonstrate the regulation between PCDHGA9 and miR-1269a. Protein mass spectrometry suggested an interaction between PCDHGA9 and HOXA1. JASPAR predicted that HOXA1 may act as a transcription factor of CXCR4. Coimmunoprecipitation, dual-luciferase assays, and nuclear-cytoplasmic fractionation experiments confirmed the molecular mechanism involving PCDHGA9, CXCR4, HOXA1, and β-catenin. Transwell, wound healing, and western blot assays were conducted to confirm the impact of PCDHGA9, miR-1269a, and CXCR4 on the invasion, metastasis, and epithelial-mesenchymal transition (EMT) functions of CRC cells in in vitro experiments. A whole-body fluorescence imaging system was used to evaluate the combined impact of miR-1269a and PCDHGA9 on the invasion and metastasis of CRC in in vivo experiments. The expression of PCDHGA9 was found to be lower in CRC tissues compared with their corresponding adjacent tissues. Low expression of PCDHGA9 potentially correlated with worse prognosis and increased chances of invasion and metastasis in CRC. miR-1269a was highly expressed in CRC tissues and acted as a negative regulator for PCDHGA9, promoting invasion, migration, and EMT of CRC cells. PCDHGA9's interaction with HOXA1 downregulated CXCR4, a transcription factor, leading to accumulation of β-catenin and further promoting invasion, migration, and EMT of CRC cells. PCDHGA9, acting as a tumor suppressor, is downregulated by miR-1269a. The low level of PCDHGA9 activates the Wnt/β-catenin pathway by releasing its interaction with HOXA1, promoting the expression of CXCR4, and causing invasion, migration, and EMT in CRC.

Proteomic Analysis of Tissue Proteins Related to Lateral Lymph Node Metastasis in Papillary Thyroid Microcarcinoma.

Patients with lateral lymph node metastasis (LLNM) may experience higher locoregional recurrence rates and poorer prognoses compared to those without LLNM, highlighting the need for effective preoperative stratification to reliably assess risk LLNM. In this study, we collected PTMC samples from Peking Union Medical College Hospital and employed data-independent acquisition mass spectrometry proteomics technique to identify protein profiles in PTMC tissues with and without LLNM. Pseudo temporal analysis and single sample gene set enrichment analysis were conducted in combination with The Cancer Genome Atlas Thyroid Carcinoma for functional coordination analysis and the construction of a prediction model based on random forest. Non-negative matrix factorization (NMF) clustering was utilized to classify molecular subtypes of PTMC. Our findings revealed that the differential activation of pathways such as MAPK and PI3K was critical in enhancing the lateral lymph node metastatic potential of PTMC. We successfully screened biomarkers via machine learning and public databases, creating an effective prediction model for metastasis. Additionally, we explored the mechanism of metastasis-associated PTMC subtypes via NMF clustering. These insights into LLNM mechanisms in PTMC may contribute to future biomarker screening and the identification of therapeutic targets.

Large-Volume Injection and Assessment of Reference Standards for n-Alkane δD and δ13C Analysis via Gas Chromatography Isotope Ratio Mass Spectrometry.

Compound-specific stable isotope analysis of hydrogen (δD) and carbon (δ13C) in organic compounds is a valuable tool in biogeochemical research. A key limitation of this method is the relatively large amount of sample required to achieve desirable precision. We developed a large-volume (20 μL) injection method that allows for high throughput analysis of less concentrated samples and tested it for δ13C and δD measurements of n-alkanes. We also conducted a comparison of reference standards and assessed several methods to normalize and correct n-alkane δD and δ13C measurements. The mean precision of the δD method based on 233 environmental n-alkane samples (two to three replications per sample) is 4.0‰ (1σ, estimated from the weighted mean of the pooled unbiased standard deviations) and 0.46‰ (1σ) for δ13C from 37 environmental samples (two to three replications per sample). The evaluation of reference standards shows that the use of n-alkane standards with large offsets in δD values in adjacent n-alkane chains can lead to biases in measurement correction. The large-volume injection method shows good reproducibility of δ13C and δD measurements of n-alkanes and reduces the required sample concentration by about 80%. We propose that for δD measurements, a reference standard set should be used in which each reference standard has a limited range of δD values and no adjacent n-alkane chains, to minimize memory effects.

LC-MS/MS confirmation of 11-nor-9-carboxy-tetrahydrocannabinol (Δ8, Δ9, Δ1°) and hexahydrocannabinol (HHC) metabolites in authentic urine specimens.

Recently, tetrahydrocannabinol (THC) isomers and other semi-synthetic cannabinoids have been introduced into the consumer market as alternatives to botanical cannabis. To assess the prevalence of these potential new analytical targets, a liquid chromatography-tandem mass spectrometry confirmation method was developed for the quantitation of seven cannabinoid metabolites and the qualitative identification of four others in urine. The validated method was applied to authentic urine specimens that screened positive by immunoassay (50 ng/mL cutoff; n=1300). The most commonly observed analytes were 11-nor-9-carboxy-Δ8- and Δ9-THC (Δ8- and Δ9-THCCOOH), with the combination of the two seen as the most prominent analyte combination found. In addition to these metabolites, Δ1°-THCCOOH was observed in 77 specimens. This is the first study to report Δ1°-THCCOOH in authentic urine specimens, with this analyte always appearing in combination with Δ9-THCCOOH. Cross-reactivity studies were performed for (6aR,9R)-Δ1°-THCCOOH using the Beckman Coulter Emit® II Plus Cannabinoid immunoassay and demonstrated cross reactivity equivalent to the Δ9-THCCOOH cutoff, providing added confidence in the reported prevalence and detection patterns. Additionally, 11-nor-9(R)-carboxy-hexahydrocannabinol (9(R)-HHCCOOH) was the most abundant stereoisomer (n=12) in specimens containing HHC metabolites alone (n=14). This is in contrast to 9(S)-HHCCOOH, which was the predominant stereoisomer in specimens containing Δ8- and/or Δ9-THCCOOH. Although HHC and Δ1°-THC metabolites are emerging toxicology findings, based on these specimens collected between April 2022 and May 2024, an analytical panel containing Δ8- and Δ9-THCCOOH appears to be sufficient for revealing cannabinoid exposure within workplace monitoring and deterrence programs.

Toxic Metals Migration from Plastic Food Contact Materials in Romania: A Health Risk Assessment

Food packaging plays an essential role in preserving food quality. However, heavy metals found in packaging materials—whether intentionally incorporated or not—can migrate into food. This study aims to evaluate the migration of specific heavy metals (Ba, Co, Cu, Zn, Al, Ni, Li, Fe, Pb, Cd, Cr, Sb) from plastic food packages (films and bags) obtained from various materials (PE, PP, PVC, composite materials) into food simulant B (3% acetic acid) using inductively coupled plasma mass spectrometry (ICP-MS). Migration tests was conducted according to EU regulations, using OM2 conditions (10 days at 40 °C). The obtained results were lower than the specific migration limits set by EU Regulation no. 10/2011 (Annex II). Both carcinogenic and non-carcinogenic risk assessments were carried out based on the specific migration data, estimating the exposure, average daily dose (ADD), hazard quotient (HQ), hazard index (HI), cancer risk (CR), and total cancer risk (TCR). The exposure values were found to be below the recommended tolerable daily intake (TDI) levels for each metal tested. Both HQ and HI values were under the limit value of 1. The average total cancer risk was 1.73 × 10−4, indicating that approximately 1.73 consumers out of 10,000 may develop a type of cancer due to chronic exposure to the tested metals. These results highlight the importance of continuous monitoring of chemical migrants from food contact materials.

Altered O-Glycans in stimulated whole saliva from patients with primary Sjögren's syndrome and non-pSS sicca.

To investigate if salivary O-linked glycans are altered in primary Sjögren's syndrome (pSS), and thus contributing to explain symptoms of oral dryness, and an impaired oral mucosal barrier function leading to changes in microbial metabolism and colonization by both pathogenic and commensal microorganisms and increased prevalence of oral diseases. O-linked oligosaccharides from stimulated whole saliva (SWS) samples from 24 patients with pSS, 38 patients with non-pSS sicca, and 23 healthy controls were analyzed using liquid chromatography mass spectrometer (LC-MS). Non-fractionated reduced and alkylated saliva was dot-blotted to PVDF-membrane and O-linked oligosaccharides were released using reductive beta-elimination. The 50 most abundant glycans were identified and their intensity compared for each sample, reflecting the relative abundance of individual monosaccharide residues. Comparison of the compositions of O-glycans in SWS samples revealed higher relative levels of sialic acid (NeuAc) and lower levels of neutral amino-monosaccharides (HexNAc) in pSS and non-pSS sicca patients than in the healthy controls. MS2 fragmentation analysis of salivary O-glycans suggests that altered sulfation, fucosylation, sialylation and distribution of core types may all contribute to the observed alteration, directly or indirectly. Additionally, the short disaccharide sialyl-Tn was most abundant in the saliva samples from patients with pSS. Our findings indicate that the salivary mucin-type O-glycan profile is altered in pSS, reflecting a dysfunction of the post-translational modification of salivary mucins leading to rheological changes of saliva, oral dryness symptoms, and impaired oral mucosal barrier function. The pathophysiological significance of the aberrant O-glycosylation needs further elucidation.

Intermolecular Interactions between Aromatic Amino Acids Investigated by Ultraviolet Photodissociation Spectroscopy of Hydrogen-Bonded Clusters of Histidine and Tryptophan Enantiomers.

Intermolecular interactions between aromatic amino acids were investigated by ultraviolet photodissociation spectroscopy of hydrogen-bonded protonated clusters of histidine (His) and tryptophan (Trp) enantiomers in the gas phase. Product ion spectra and photodissociation spectra in the wavelength range of the S1-S0 transition of Trp at several temperatures (8-100 K) were obtained using a tandem mass spectrometer equipped with an electrospray ionization source and a cold ion trap. l-Trp detachment forming protonated His was the main pathway. Two bands observed at 288 and 285 nm in the photodissociation spectra of heterochiral H+(d-His)(l-Trp) indicated the coexistence of two types of conformers. The bands at 288 and 285 nm were attributed to the conformers formed from stronger and weaker intermolecular interactions, respectively. In the spectra of homochiral H+(l-His)(l-Trp), only the band due to the stronger interactions was observed at 288 nm. The intermolecular interactions of l-His with l-Trp were stronger than those of d-His with l-Trp.

A Proof-of-Principle Study for δ15N Measurements of Aqueous Dissolved Nitrate With a Modified LC-IRMS Interface.

The analysis of nitrogen isotopes in aqueous dissolved nitrate is an effective method for identifying pollution sources and offers the potential to study the nitrogen cycle. However, the measurement of nitrogen isotope ratios of nitrate still requires extensive sample preparation or derivatization. In this study, a modified commercially available liquid chromatography-isotope ratio mass spectrometer (LC-IRMS) interface is presented that enables automated measurement of δ15N signatures from nitrate by online reduction of nitrate in two consecutive steps. First, vanadium(III) chloride is used as a reducing agent to convert NO3 - to NxOy under acidic conditions. The mix of nitrogen oxides is then transferred into a stream of helium and reduced to nitrogen (N2) analysis gas via a hot copper reactor. Prior to the online conversion of aqueous nitrate into elemental nitrogen, the sample was chromatographically separated from potential matrix effects on a PGC column. Precision was achieved at a level below 1.4‰ by injecting 10 μL of 50 mg L-1 N, using five different nitrate standards and reference materials. These materials spanned a range of more than 180‰ in δ15N. To demonstrate the applicability of the method, we measured water samples from an enrichment experiment, where isotopically enriched ammonium chloride was administered into a small river over the course of 2 weeks. In contrary to our expectation, the δ15N values of river nitrate showed values between +0.4 ± 0.4‰ and +4.1 ± 0.3‰, varying over a small range of 3.7‰. Our study showed that the measurement of nitrate nitrogen isotope ratios with a modified LC-IRMS system is possible but that further modifications and improvements would be necessary for a robust and user-friendly instrument.

Preservation of Luminescent Properties of Zinc Complexes in the Solid State by Accumulating into Polyhedral Oligomeric Silsesquioxane

Multinuclear complexes have attracted great attention because of their superior properties originating from the cooperative effects between the metal ions. In this study, we synthesized polynuclear zinc complexes by chelation between the side‐chains of polyhedral oligomeric silsesquioxane (POSS). From the NMR spectroscopy, high‐resolution mass spectrometry and Fourier transform infrared spectroscopy (FT‐IR), it was confirmed the four equivalents of zinc ions were coordinated to the single POSS molecule. Optical measurements indicated that luminescent properties can be preserved even in the solid state. The three‐dimensional structure of POSS should play a significant role in suppressing concentration quenching followed by solid‐state emission properties.

Potential urinary volatile organic compounds as screening markers in cancer – a review

Early detection of cancer typically facilitates improved patient outcomes; however, many cancers are not easily diagnosed at an early stage. One potential route for developing new, non-invasive methods of cancer detection is by testing for cancer-related volatile organic compounds (VOCs) biomarkers in patients’ urine. In this review, 44 studies covering the use and/or identification of cancer-related VOCs were examined, including studies which examined multiple types of cancer simultaneously, as well as diverse study designs. Among these studies the most studied cancers included prostate cancer (29% of papers), lung cancer (22%), breast cancer (20%), and bladder cancer (18%), with a smaller number of studies focused on colorectal cancer, cervical cancer, skin, liver cancer and others. Importantly, most studies which produced a VOC-based model of cancer detection observed a combined sensitivity and specificity above 150%, indicating that urine-based methods of cancer detection show considerable promise as a diagnostic tool. Mass spectrometry (MS) and electronic noses (eNose) were the most employed tools used in the detection of VOCs, while animal-based models were less common. In terms of VOCs of interest, 47 chemical species identified as correlated with various types of cancer in at least two unrelated papers, some of which were consistently up- or down-regulated in cancer patients, and which may represent useful targets for future studies investing urinary VOC biomarkers of cancer. Overall, it was concluded that research in this field has shown promising results, but more work may be needed before the widespread adoption of these techniques takes place.

Studying Structural Details in Complex Samples: II. High Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) Coupled to High Resolution Tandem Mass Spectrometry (MS/MS).

The elucidation of structural motifs in extremely complex mixtures is very difficult since the standard methods for structural elucidation are not capable to provide significant information on a single molecule. The best method for the analysis of complex mixtures is ultrahigh resolution mass spectrometry, but the utilization of this method alone does not provide significant information about structural details. Here, a combination with a separation method is necessary. While chromatography is a well-established technique, it has some disadvantages in regard to the separation of complex mixtures, as often no separation of individual isomers is possible. Therefore, here the combination of an ion mobility separation with ultrahigh resolution mass spectrometry is evaluated. As a sample matrix, crude oil is used because it is an excellent matrix to develop new analytical techniques on complex samples. Crude oil is the most complex natural sample known, but only little information is available on the structural identity or functionalities due to a high number of structural isomers or isobars. A lab-built APPI/APLI-FAIMS source was revised to optimize ion transmission and used to follow up on the ion mobility of crude oil constituents after photoionization. An MS/MS approach using collision-induced dissociation (CID) was used to elucidate structural motifs of the transmitted isomers.

Synthesis, Crystal Structures, Antimicrobial Activity, and Acute Toxicity Evaluation of Chiral Zn(II) Schiff Base Complexes

Four mononuclear bioefficient zinc coordination complexes [Zn(NN)3](ClO4)2 (A–D) involving chiral bidentate Schiff base ligands have been synthesized and characterized by IR, 1H, and 13C NMR spectroscopy and mass spectrometry. X-ray crystal structures of three of the zinc complexes revealed that the zinc metal ion is hexacoordinated, exhibiting a distorted octahedral geometry where both the nitrogen atoms (NN = pyridyl and imine) of imines are coordinated to the central zinc ion. The isolated zinc complexes were evaluated for their antimicrobial activity in vitro against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, displaying varying levels of growth inhibition. An acute toxicity test conducted using Artemia salina and Swiss albino mice showed that the zinc complexes A–D were non-toxic towards A. salina at concentrations below 414, 564, 350, and 385 µM, respectively, and did not affect liver biochemical parameters, although pyknosis was induced in hepatocytes of the treated mice.

Prediction of risk for early or very early preterm births using high-resolution urinary metabolomic profiling

BackgroundPreterm birth (PTB) is a serious health problem. PTB complications is the main cause of death in infants under five years of age worldwide. The ability to accurately predict risk for PTB during early pregnancy would allow early monitoring and interventions to provide personalized care, and hence improve outcomes for the mother and infant.ObjectiveThis study aims to predict the risks of early preterm (< 35 weeks of gestation) or very early preterm (≤ 26 weeks of gestation) deliveries by using high-resolution maternal urinary metabolomic profiling in early pregnancy.DesignA retrospective cohort study was conducted by two independent preterm and term cohorts using high-density weekly urine sampling. Maternal urine was collected serially at gestational weeks 8 to 24. Global metabolomics approaches were used to profile urine samples with high-resolution mass spectrometry. The significant features associated with preterm outcomes were selected by Gini Importance. Metabolite biomarker identification was performed by liquid chromatography tandem mass spectrometry (LCMS-MS). XGBoost models were developed to predict early or very early preterm delivery risk.Setting and participantsThe urine samples included 329 samples from 30 subjects at Stanford University, CA for model development, and 156 samples from 24 subjects at the University of Alabama, Birmingham, AL for validation.Results12 metabolites associated with PTB were selected and identified for modelling among 7,913 metabolic features in serial-collected urine samples of pregnant women. The model to predict early PTB was developed using a set of 12 metabolites that resulted in the area under the receiver operating characteristic (AUROCs) of 0.995 (95% CI: [0.992, 0.995]) and 0.964 (95% CI: [0.937, 0.964]), and sensitivities of 100% and 97.4% during development and validation testing, respectively. Using the same metabolites, the very early PTB prediction model achieved AUROCs of 0.950 (95% CI: [0.878, 0.950]) and 0.830 (95% CI: [0.687, 0.826]), and sensitivities of 95.0% and 60.0% during development and validation, respectively.ConclusionModels for predicting risk of early or very early preterm deliveries were developed and tested using metabolic profiling during the 1st and 2nd trimesters of pregnancy. With patient validation studies, risk prediction models may be used to identify at-risk pregnancies prompting alterations in clinical care, and to gain biological insights of preterm birth.

Proteomic Markers of Aging and Longevity: A Systematic Review

This article provides a systematic review of research conducted on the proteomic composition of blood as part of a complex biological age estimation. We performed a comprehensive analysis of 17 publicly available datasets and compiled an integral list of proteins. These proteins were sorted based on their detection probability using mass spectrometry in human plasma. We propose this list as a basis for creating a panel of peptides and quantifying the content of selected proteins in the format of a proteomic aging clock. The selected proteins are especially notable for their roles in inflammatory processes and lipid metabolism. Our findings suggest, for the first time, that proteins associated with systemic disorders, including those approved by the FDA for clinical use, could serve as potential markers of aging.

Effect of "Xingshen-Jieyu" electroacupuncture on serum differential metabolites in patients with depression based on metabolomics

To explore the effect of "Xingshen-Jieyu" (inducing resuscitation and dispel ling melancholy) electroacupuncture (EA) on serum metabolites in patients with depression and its underlying mechanisms through serum non-targeted metabolomics. Fifteen depression patients were subjected into the EA group, and 15 healthy volunteers were matched into the healthy group. EA (2 Hz/15 Hz, a tolerable strength) was applied to Baihui (GV20), Shenting (GV24), Toulinqi (GB15), Benshen (GB13), Touwei (ST8), Xuanli (GB6) and Qubin (GB7) for 30 min, 3 times a week for 6 weeks. The severity of depression was assessed using Hamilton Depression Scale-17 (HAMD-17) and Hamilton Anxiety Scale (HAMA), the degree of fatigue was evaluated using Fatigue Scale-14 (FS-14). The subjects sleep quality was assessed using Pittsburgh sleep quality index (PSQI). Blood samples were collected before and after the treatment for processing serum to perform non-targeted metabolomics profile detection using ultra-high-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), and Partial Least Squares Discriminant Analysis (PLS-DA, a statistical approach). Differential metabolites were screened and pathway enrichment analysis was performed. After the treatment, the scores of HAMD-17, HAMA, PSQI and FS-14 of depression patients were significantly lowered in the EA group (P<0.05). Compared with the healthy subjects, 46 differential metabolites (21 up-regulated, 25 down-regulated) were screened in patients with depression. Compared with pre-treatment in the EA group, 19 differential (17 up-regulated, and 2 down-regulated) metabolites were screened. Four down-regulated metabolites of the 46 differential metabolites in depression patients were recovered after EA treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of differential metabolites before and after EA showed that 19 metabolic pathways were enriched, mainly involving glutaminergic synapses, GABAergic synapses and several amino acid metabolism related pathways. "Xingshen-Jieyu" EA mainly regulates the metabolism of amino acids, and activities of neurotransmitter glutamate and GABA, and restores the excitatory/inhibitory balance, thus playing a role in improving depression.

Cationic Lipid Derived from a Basic Amino Acid: Design and Synthesis

One of the major challenges in gene therapy is the efficient and safe introduction of nucleic acids into eukaryotic cells. This process requires overcoming various biological barriers and navigating complex pathways to reach target cells and achieve their biological function. To address this obstacle, numerous transfection methods have been developed, including physical techniques and the use of genetic vectors, both viral and non-viral. However, to date, no transfection method is 100% safe and efficient. Within the spectrum of non-viral genetic vectors, cationic liposomes formed by cationic lipids stand out for their ability to protect and deliver therapeutic NA. These liposomes offer greater biocompatibility and lower immunogenicity compared to viral vectors, although they still do not match the efficiency of viral delivery systems. Consequently, ongoing research focuses on synthesizing a wide variety of cationic lipids in the search for compounds that provide high transfection efficiency with minimal cytotoxicity. This study aimed to design and synthesize a novel cationic lipid (CholCadLys) derived from natural cellular molecules for transferring genetic material to eukaryotic cells. The lipid was synthesized using cholesteryl chloroformate for the hydrophobic region, cadaverine as a linker, and lysine for the polar region, connected by carbamate and amide bonds, respectively. Identification was confirmed through thin-layer chromatography, purification through preparative chromatography, and characterization via infrared spectroscopy and mass spectrometry. The synthesis yielded a 60% success rate, with stable nanoliposomes averaging 76 nm in diameter. Liposomes were formed using this CL and commercial neutral lipids, characterized by transmission electron microscopy and Nanoparticle Tracking Analysis. These liposomes, combined with plasmid DNA, formed lipoplexes used to transfect Hek-293 FT cells, achieving up to 40% transfection efficiency without cytotoxicity in the mixture of CholCadLys and CholCad. This novel CL demonstrates potential as an efficient, safe, and cost-effective gene transfer system, facilitating further development in gene therapy.

Chemical characteristics of BTEX, Formaldehyde and Trace gases: concentration, ozone formation potential and source apportionment at a campus site of Agra.

Benzene, toluene, ethylbenzene, xylenes (BTEX) and formaldehyde (HCHO) impact the environment and human health due to their deleterious effect and are of great concern. In the present study, diurnal and seasonal trend of BTEX and HCHO along with trace gases are reported. BTEX samples were collected by activated charcoal tubes and analysed by Gas Chromatograph coupled with Mass Spectrometer and Flame Ionization Detector (GC-MS/FID) and formaldehyde sampling was done by impinger method and analysed by UV-Visible Spectroscopy. Summation BTEX varied from 50.3 to 188.3µgm-3 (average = 74.8 ± 31.8µgm-3). Amongst all species, toluene was the most abundant. Highest levels of BTEX, NOx and CO were observed in winter (96.4 ± 39.1µgm-3, 11.9 ± 7.8ppb and 540.8 ± 402.0ppb respectively) probably due to enhanced local emissions, stagnant weather conditions resulting in dilution and dispersion of pollutants and weak photochemical removal. Lower values are seen during monsoon (58.6 ± 25.4µgm-3, 7.6 ± 6.1µgm-3 and 149.8 ± 68.7µgm-3) as a consequence of rain showers and washout effect leading to clean atmospheric conditions. Further, ozone forming potential (OFP) BTEX was determined based on their reactivity with OH˙radical and concentration. Toluene (90.9µgm-3) was the largest contributor to ozone formation, whereas benzene (9.1µgm-3) was the lowest. Source apportionment of BTEX was determined based on estimation of diagnostic ratios, correlations and positive matrix factorization (PMF) analysis and revealed emissions from vehicles was the main source. Air mass back trajectory analysis for different seasons shows the impact of long-range during the summer season and localized air masses during winter season. The results of the current study provide a better understanding of OFP and sources of BTEX and HCHO to formulate effective pollution management.