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24 pages, 3236 KB  
Article
PtNiSnO2 Nanoframes as Advanced Electrode Modifiers for Ultrasensitive Detection of Trazodone in Complex Matrices
by Małgorzata Suchanek, Agata Krakowska, Kamil Szmuc, Dariusz Łukowiec, Marcel Zambrzycki and Robert Piech
Int. J. Mol. Sci. 2025, 26(18), 8861; https://doi.org/10.3390/ijms26188861 - 11 Sep 2025
Viewed by 469
Abstract
A novel voltammetric sensor was constructed by modifying a glassy carbon electrode with a composite material consisting of platinum–nickel-doped tin oxide and carbon black (PtNiSnO2-CB/GCE), enabling highly sensitive differential pulse voltammetry (DPV) determination of trazodone HCl (TRZ). The DPV experimental parameters, [...] Read more.
A novel voltammetric sensor was constructed by modifying a glassy carbon electrode with a composite material consisting of platinum–nickel-doped tin oxide and carbon black (PtNiSnO2-CB/GCE), enabling highly sensitive differential pulse voltammetry (DPV) determination of trazodone HCl (TRZ). The DPV experimental parameters, including the composition of the supporting electrolyte and instrumental settings, were carefully optimized to achieve maximum analytical efficiency. Within the linear range of 1–10 µM, quantification of TRZ molecules could be performed without the preconcentration step. When applying a 60 s accumulation time (in the range 0.02–0.2 µM of TRZ), the detection limit reached 4.1 nM (1.67 mg L−1), indicating superior sensitivity compared to previously reported voltammetric techniques. The method demonstrated good reproducibility, with a relative standard deviation of 4.3% for 10 repeated measurements at 0.06 µM TRZ. The developed sensor exhibits excellent stability, simplicity of fabrication, and operational convenience. Its practical applicability was confirmed by the successful analysis of molecules of TRZ in diverse sample types, including pharmaceutical products, urine, plasma, river water, and artificial gastric and intestinal fluids, with recovery rates between 97.7% and 104.2%. Flow injection analysis (FIA) with amperometric detection was also performed for TRZ molecule determination. Full article
(This article belongs to the Special Issue Electrochemistry: Molecular Advances and Challenges)
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14 pages, 868 KB  
Article
Development of a Sensitive HILIC-MS/MS Method for Quantification of Melamine, Derivatives, and Potential Precursors in Various Water Matrices
by Merle Käberich, Lisann Nemetz and Frank Sacher
Analytica 2025, 6(3), 27; https://doi.org/10.3390/analytica6030027 - 19 Aug 2025
Viewed by 778
Abstract
Melamine (MEL) has broad applications and can be released to the aquatic environment from various sources, including industry, agriculture, traffic, and household articles. In addition, MEL derivatives ammeline (AMN), ammelide (AMD), and cyanuric acid (CYA) as well as potential precursors cyromazine (CYRO) and [...] Read more.
Melamine (MEL) has broad applications and can be released to the aquatic environment from various sources, including industry, agriculture, traffic, and household articles. In addition, MEL derivatives ammeline (AMN), ammelide (AMD), and cyanuric acid (CYA) as well as potential precursors cyromazine (CYRO) and hexa(methoxymethyl)melamine (HMMM) are relevant related substances. However, occurrence and transformation in water resources has not yet been thoroughly investigated. Here, we developed a sensitive analytical method for quantification of these analytes by hydrophilic interaction liquid chromatography (HILIC) coupled to tandem mass spectrometry (MS/MS). Direct injection achieved limits of quantification (LOQs) of 0.1 µg/L (AMN 0.2 µg/L; CYA 1 µg/L), while LOQs could be improved to 0.01 µg/L (CYA 0.05 µg/L) by applying evaporation for analyte pre-concentration. The method was extensively validated, showing good recovery, repeatability, and linearity. The evaluation of the matrix effects revealed method applicability for various water matrices, including surface water and wastewater. During proof-of-concept measurements, HMMM in combination with MEL and its derivatives was found in multiple samples, emphasizing the importance of including precursors. In the future, the developed method with its novelty of covering both MEL derivatives and precursors can be applied for comprehensive monitoring programs elucidating MEL sources and transformation in water resources. Full article
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17 pages, 3356 KB  
Article
Impact of Adaptive Process Control on Mechanical Properties of Plastic Parts and Process Robustness
by Tomasz Olszewski, Danuta Matykiewicz and Michał Jakubowicz
Appl. Sci. 2025, 15(16), 8829; https://doi.org/10.3390/app15168829 - 10 Aug 2025
Viewed by 677
Abstract
This work aimed to assess the influence of the iQ Weight Control System on the weight, dimensional stability, and mechanical properties of injection-molded samples. The properties of products made from glass fiber-reinforced polyamide and 50% regrind from post-production waste were evaluated. The mechanical [...] Read more.
This work aimed to assess the influence of the iQ Weight Control System on the weight, dimensional stability, and mechanical properties of injection-molded samples. The properties of products made from glass fiber-reinforced polyamide and 50% regrind from post-production waste were evaluated. The mechanical properties, such as impact strength and tensile strength, were measured to determine the material’s performance. Additionally, a spiral flow test was conducted to verify the process robustness and repeatability when producing with either virgin material or a blend of virgin and regrind material. The spiral flow test, which involves injecting the polymer melt into a spiral mold, provides insights into the processability and flow characteristics of the polymer under high shear rates. This test is crucial for assessing the consistency of the injection molding process and ensuring that the material maintains its properties across different production batches. Results demonstrated that, despite the viscosity reduction associated with regrind, the system successfully maintained a consistent shot weight, thereby stabilizing the amount of material injected into the mold cavity. The iQ Weight Control System activation led to an increase in impact strength from 9.50 kJ/m2 to 10.78 kJ/m2 for virgin samples and from 9.26 kJ/m2 to 9.73 kJ/m for a 50/50 virgin/regrind blend. Full article
(This article belongs to the Special Issue Mechanical Properties and Numerical Modeling of Advanced Materials)
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13 pages, 2695 KB  
Article
Non-Surgical Rhinoplasty After Nasal Skin Cancer Reconstruction: Enhancing Esthetic Outcomes
by Shahin Tahan Shoushtari, Charles Savoldelli, Héloïse Gobillot, Laurent Castillo, Gilles Poissonnet, Philippe Kestemont, Grégoire D’Andréa and Clair Vandersteen
J. Clin. Med. 2025, 14(15), 5394; https://doi.org/10.3390/jcm14155394 - 31 Jul 2025
Viewed by 1390
Abstract
Objectives: Nasal reconstructive surgery following skin cancer resection is challenging, with esthetic concerns impacting patients’ quality of life. Non-surgical rhinoplasty may be an alternative to repeated surgeries. This study aimed to evaluate non-surgical rhinoplasty esthetic benefits and subjective patient outcomes after skin cancer [...] Read more.
Objectives: Nasal reconstructive surgery following skin cancer resection is challenging, with esthetic concerns impacting patients’ quality of life. Non-surgical rhinoplasty may be an alternative to repeated surgeries. This study aimed to evaluate non-surgical rhinoplasty esthetic benefits and subjective patient outcomes after skin cancer resection. Methods: We conducted a retrospective study on patients with post-operative esthetic dissatisfaction after nasal skin cancer surgery, who underwent non-surgical rhinoplasty with hyaluronic acid. Subjective benefits were evaluated with the FACE-Q Rhinoplasty self-questionnaire at three consultations: before injection (baseline), and at one and two months after. Two-dimensional and three-dimensional Vectra H2 photographs were used to assess subjective esthetic concerns and objective volumetric changes. Results: The study included six female patients with an average age of 58.3 years. They had undergone, on average, five nasal surgeries for cancer. The mean FACE-Q scores were 53.3 (±10.31), 77.5 (±4.18), and 79.7 (±6.76), respectively, at baseline, one month, and two months. Significant differences were observed between baseline and one month (p < 0.001) and between baseline and two months (p < 0.001), but not between one and two months. The was a mean volumetric gain of 1.13 mL at one month and 1.19 mL at two months. Conclusions: This preliminary study suggested that hyaluronic acid-based non-surgical rhinoplasty could improve esthetic outcomes and quality of life in patients who had undergone nasal skin cancer surgery. These findings highlight a potential role for this minimally invasive technique in selected post-reconstructive cases, although the small sample size limited the generalizability of the results and underlined the need for further prospective evaluation. Full article
(This article belongs to the Special Issue Facial Plastic and Cosmetic Medicine)
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23 pages, 11818 KB  
Article
Cryopreservation and Validation of Microfragmented Adipose Tissue for Autologous Use in Knee Osteoarthritis Treatment
by Marija Zekušić, Petar Brlek, Lucija Zenić, Vilim Molnar, Maja Ledinski, Marina Bujić Mihica, Adela Štimac, Beata Halassy, Snježana Ramić, Dominik Puljić, Tiha Vučemilo, Carlo Tremolada, Srećko Sabalić, David C. Karli, Dimitrios Tsoukas and Dragan Primorac
Int. J. Mol. Sci. 2025, 26(14), 6969; https://doi.org/10.3390/ijms26146969 - 20 Jul 2025
Viewed by 1082
Abstract
Micro-fragmented adipose tissue (MFAT) is a promising autologous therapy for knee osteoarthritis. To avoid repeated liposuction procedures for its clinical application, MFAT obtained from patients with knee osteoarthritis was stored at −80 °C in a tissue bank. This study describes the preparation, cryopreservation, [...] Read more.
Micro-fragmented adipose tissue (MFAT) is a promising autologous therapy for knee osteoarthritis. To avoid repeated liposuction procedures for its clinical application, MFAT obtained from patients with knee osteoarthritis was stored at −80 °C in a tissue bank. This study describes the preparation, cryopreservation, thawing, and washing, as well as comprehensive analysis of cell populations in fresh and MFAT thawed after two years. Immunophenotyping of both fresh and thawed MFAT showed a significant presence of endothelial progenitors and pericytes in the stromal vascular fraction. Viability before (59.75%) and after freezing (55.73%) showed no significant difference. However, the average cell count per gram of MFAT was significantly reduced in thawed samples (3.00 × 105) compared to fresh ones (5.64 × 105), likely due to processing steps. Thawed MFAT samples showed increased CD73 expression on the CD31highCD34high subset of EP and SA-ASC, as well as increased expression of CD105 on EP, the CD31lowCD34low subset of EP, pericytes, and SA-ASC. Microbiological testing confirmed 100% sterility, and double washing efficiently removed DMSO, confirming sample safety. Histological analysis revealed healthy, uniformly shaped adipocytes with intact membranes. This approach allows accurate estimation of cell yield for intra-articular injection, ensuring delivery of the target cell number into the knee. Quality control analysis confirms that cryopreserved MFAT retains high cellular and structural integrity, supporting its safety and suitability for clinical application. Full article
(This article belongs to the Section Molecular Biology)
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14 pages, 574 KB  
Article
FMR1 Allelic Complexity and IVF Fertilization Success: Limitations and Future Perspectives
by Bárbara Rodrigues, Emídio Vale-Fernandes, Vanessa Sousa, Isabel Marques, Rosário Santos, António J. A. Nogueira and Paula Jorge
Int. J. Mol. Sci. 2025, 26(12), 5752; https://doi.org/10.3390/ijms26125752 - 16 Jun 2025
Viewed by 1095
Abstract
We investigated whether FMR1 allelic complexity—integrating CGG repeat length with the number and pattern of AGG interspersions—can be used as a predictor of ovarian reserve and in vitro fertilization (IVF) success. This cohort study included 124 females with infertility attributed to female factors [...] Read more.
We investigated whether FMR1 allelic complexity—integrating CGG repeat length with the number and pattern of AGG interspersions—can be used as a predictor of ovarian reserve and in vitro fertilization (IVF) success. This cohort study included 124 females with infertility attributed to female factors undergoing intracytoplasmic sperm injection (ICSI). The total CGG repeat lengths and AGG interspersion patterns of the FMR1 gene were determined by conventional polymerase chain reaction (PCR) and triplet-primed PCR. The allelic complexity (allelic score) was calculated using a previously described formula by combining the allelic scores, allowing for the stratification of samples into equivalent and dissimilar groups. No statistically significant differences were observed in ovarian reserve markers or overall IVF outcomes between the two groups. However, within the dissimilar group, the allelic score of allele 1 was significantly correlated with the number of both injected metaphase II and two-pronuclei oocytes. These findings suggest that FMR1 allelic complexity may contribute to predicting IVF success, particularly in females classified in the dissimilar group, who appear more susceptible to IVF failure than those in the equivalent group. Further research into the predictive utility of FMR1 could provide valuable insights for fertility assessment and enhance assisted reproductive technologies. Full article
(This article belongs to the Special Issue Advances in Genetics of Human Reproduction)
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16 pages, 4589 KB  
Article
Immunotoxicity of Four Per- and Polyfluoroalkyl Substances Following 28-Day Oral Repeat Dosing in Rats Assessed by the Anti-Sheep Red Blood Cell IgM Response
by Michael F. Hughes, Michael J. DeVito, Grace Patlewicz, Russell S. Thomas, Linda D. Adams, Jeffrey L. Ambroso, Xi Yang, Bindu G. Upadhyay, Stefanie C. M. Burleson and Elaina M. Kenyon
Toxics 2025, 13(6), 490; https://doi.org/10.3390/toxics13060490 - 10 Jun 2025
Viewed by 798
Abstract
Some PFASs are immunotoxic in rodent models and associated with diminished vaccine response in exposed humans. This study assessed the immunotoxicity of four PFASs via the T cell-dependent IgM antibody response (TDAR) to sheep red blood cells (SRBCs) in adult male rats following [...] Read more.
Some PFASs are immunotoxic in rodent models and associated with diminished vaccine response in exposed humans. This study assessed the immunotoxicity of four PFASs via the T cell-dependent IgM antibody response (TDAR) to sheep red blood cells (SRBCs) in adult male rats following 28-day oral repeat dosing. The PFASs included 1H,1H,9H-perfluorononyl acrylate (PFNAC), 1H,1H,2H,2H-perfluorohexyl iodide (PFHI), 2-chlorotetrafluoropropionic acid (CTFPA), and 3,3,4,4,5,5,5-heptafluoropentan-2-one (MHFPK), administered in corn oil. The positive control was cyclophosphamide (CPS). Rats were dosed with vehicle or PFAS from Days 0 to 27. On Day 22, an immunogenic dose of SRBCs was administered intravenously. Positive control animals were administered CPS by intraperitoneal injection from Days 22–27. On Day 28, the animals were euthanized; blood, thymus, and spleen samples were collected and weighed. Serum IgM was quantified by enzyme-linked immunosorbent assay. Body weights were unaffected in PFAS-treated rats, except for 3 and 10 mg/kg/day PFNAC-treated rats on Days 24, 27, and 28. Relative spleen and thymus weights and serum IgM levels were not affected by the PFASs at the doses tested, whereas CPS-treated animals had significant decreases in these parameters. The rat TDAR, as assessed by the anti-SRBC IgM response, was not affected by these four PFAS test agents following a 28-day oral exposure. Full article
(This article belongs to the Special Issue PFAS Toxicology and Metabolism—2nd Edition)
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27 pages, 3320 KB  
Article
Urinary Metabolic Profiling During Epileptogenesis in Rat Model of Lithium–Pilocarpine-Induced Temporal Lobe Epilepsy
by Fatma Merve Antmen, Emir Matpan, Ekin Dongel Dayanc, Eylem Ozge Savas, Yunus Eken, Dilan Acar, Alara Ak, Begum Ozefe, Damla Sakar, Ufuk Canozer, Sehla Nurefsan Sancak, Ozkan Ozdemir, Osman Ugur Sezerman, Ahmet Tarık Baykal, Mustafa Serteser and Guldal Suyen
Biomedicines 2025, 13(3), 588; https://doi.org/10.3390/biomedicines13030588 - 27 Feb 2025
Viewed by 1469
Abstract
Background/Objectives: Temporal lobe epilepsy (TLE) often develops following an initial brain injury, where specific triggers lead to epileptogenesis—a process transforming a healthy brain into one prone to spontaneous, recurrent seizures. Although electroencephalography (EEG) remains the primary diagnostic tool for epilepsy, it cannot [...] Read more.
Background/Objectives: Temporal lobe epilepsy (TLE) often develops following an initial brain injury, where specific triggers lead to epileptogenesis—a process transforming a healthy brain into one prone to spontaneous, recurrent seizures. Although electroencephalography (EEG) remains the primary diagnostic tool for epilepsy, it cannot predict the risk of epilepsy after brain injury. This limitation highlights the need for biomarkers, particularly those measurable in peripheral samples, to assess epilepsy risk. This study investigated urinary metabolites in a rat model of TLE to identify biomarkers that track epileptogenesis progression across the acute, latent, and chronic phases and elucidate the underlying mechanisms. Methods: Status epilepticus (SE) was induced in rats using repeated intraperitoneal injections of lithium chloride–pilocarpine hydrochloride. Urine samples were collected 48 h, 1 week, and 6 weeks after SE induction. Nuclear magnetic resonance spectrometry was used for metabolomic analysis, and statistical evaluations were performed using MetaboAnalyst 6.0. Differences between epileptic and control groups were represented using the orthogonal partial least squares discriminant analysis (OPLS-DA) model. Volcano plot analysis identified key metabolic changes, applying a fold-change threshold of 1.5 and a p-value < 0.05. Results: The acute phase exhibited elevated levels of acetic acid, dihydrothymine, thymol, and trimethylamine, whereas glycolysis and tricarboxylic acid cycle metabolites, including pyruvic and citric acids, were reduced. Both the acute and latent phases showed decreased theobromine, taurine, and allantoin levels, with elevated 1-methylhistidine in the latent phase. The chronic phase exhibited reductions in pimelic acid, tiglylglycine, D-lactose, and xanthurenic acid levels. Conclusions: These findings highlight stage-specific urinary metabolic changes in TLE, suggesting distinct metabolites as biomarkers for epileptogenesis and offering insights into the mechanisms underlying SE progression. Full article
(This article belongs to the Section Neurobiology and Clinical Neuroscience)
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19 pages, 13064 KB  
Article
Research on Operation and Maintenance Management of Subsurface Drip Irrigation System in the North China Plain: A Case Study in the Heilonggang Region
by Yudong Zheng, Hongkai Dang, Xin Hui, Dongyu Cai, Haohui Zhang, Jingyuan Xue, Xuetong Liu, Junyong Ma, Caiyun Cao, Xindong Niu, Chunlian Zheng and Kejiang Li
Water 2025, 17(4), 508; https://doi.org/10.3390/w17040508 - 11 Feb 2025
Cited by 1 | Viewed by 2045
Abstract
Subsurface drip irrigation is an advanced technique that significantly enhances agricultural water efficiency and conserves irrigation resources. The Heilonggang region is highly representative of the maize–wheat rotation system in China. This region was selected for conducting operations and maintenance experiments on subsurface drip [...] Read more.
Subsurface drip irrigation is an advanced technique that significantly enhances agricultural water efficiency and conserves irrigation resources. The Heilonggang region is highly representative of the maize–wheat rotation system in China. This region was selected for conducting operations and maintenance experiments on subsurface drip irrigation systems. The primary objective of this study was to determine the most suitable type of drip tape for application in the North China Plain and to identify specific maintenance measures necessary to ensure the long-term functionality of subsurface drip irrigation systems. The experiment was conducted in Jing County, Hengshui City. Anti-blocking drip tape (Netafim Co., Ltd. Beijing, China) with automatic functionality was evenly laid in the test area. The experimental area was divided into six rotational irrigation groups. The key parameter examined in this single-factor experiment was the drip tape wall thickness, with values of 0.2, 0.225, 0.25, 0.28, 0.31, and 0.38 mm. Drip tape treatments were randomly sampled in rotational irrigation groups, and there were three repeat plots in each treatment. Each replicate plot contained ten drip irrigation belts spaced 60 cm apart, with an interval of more than 2 m between adjacent plots. The subsurface drip irrigation system was installed in October 2023. Prior to irrigation, drip tape troubleshooting was conducted and recorded manually on 12 March 2024 (wheat regreening stage) and 29 June 2024 (maize-sowing stage). The experimental findings indicated that the primary factor influencing the stability of the irrigation system was the wall thickness of the drip tapes, while other system components operated efficiently. A significant correlation was observed between the wall thickness of the drip tape and the number of water leakage points (p < 0.05), with an absolute correlation coefficient exceeding 0.9. The number of leakage points in drip tapes with wall thicknesses of 0.2–0.28 mm (267 instances) was significantly higher than those with wall thicknesses of 0.31–0.38 mm (29 instances), primarily due to damage caused by mole crickets and wireworms. Following the injection of 40% phoxim, 2.5% lambda-cyhalothrin, and 70% imidacloprid insecticides (at a cost of 16.7 USD·ha−1) into the subsurface drip irrigation system, the insect pests were nearly eradicated within one month. A cumulative cost evaluation over a 6–10-year period recommended the use of drip tapes with a wall thickness of 0.31 mm and the application of insecticides every 1–2 months to maintain optimal system performance in this region. These measures can effectively support the stable operation of this irrigation technique at a relatively low cost. Full article
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19 pages, 2690 KB  
Article
Development and Validation of Targeted Metabolomics Methods Using Liquid Chromatography–Tandem Mass Spectrometry (LC-MS/MS) for the Quantification of 235 Plasma Metabolites
by Kangkang Xu, Franz Berthiller, Barbara U. Metzler-Zebeli and Heidi E. Schwartz-Zimmermann
Molecules 2025, 30(3), 706; https://doi.org/10.3390/molecules30030706 - 5 Feb 2025
Cited by 3 | Viewed by 5565
Abstract
Plasma contains metabolites with diverse physicochemical properties, ranging from highly polar to highly apolar, and concentrations spanning at least nine orders of magnitude. Plasma metabolome analysis is valuable for monitoring health and evaluating medical interventions but is challenging due to the metabolome’s diversity [...] Read more.
Plasma contains metabolites with diverse physicochemical properties, ranging from highly polar to highly apolar, and concentrations spanning at least nine orders of magnitude. Plasma metabolome analysis is valuable for monitoring health and evaluating medical interventions but is challenging due to the metabolome’s diversity and complexity. This study aims to develop and validate targeted LC-MS/MS methods for quantifying 235 mammalian metabolites from 17 compound classes in porcine plasma without prior derivatization. Utilizing reversed-phase and hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry, each analyte is identified and quantified using two selected reaction monitoring (SRM) transitions. Fast polarity switching and scheduled SRM enhance the metabolome coverage and throughput, enabling the analysis of one sample in about 40 min. A simple “dilute and shoot” sample preparation protocol was employed, with samples injected at two dilution levels to align metabolite concentrations within calibration curve ranges. Validation in porcine plasma included assessments of carryover, linearity, detection and quantification limits, repeatability and recovery. The method was further applied to plasma samples from various animal species, demonstrating its applicability to human and animal studies. This study establishes two robust LC-MS/MS methods for comprehensive porcine plasma metabolome quantification, advancing large-scale targeted metabolomics in biomedical research. Full article
(This article belongs to the Special Issue The Application of LC-MS in Pharmaceutical Analysis)
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13 pages, 1533 KB  
Article
Protocol for the Determination of Total Iodine in Iodized Table Salts Using Ultra-High-Performance Liquid Chromatography
by Mohd Azerulazree Jamilan, Aswir Abd Rashed and Mohd Fairulnizal Md Noh
Chemosensors 2025, 13(2), 46; https://doi.org/10.3390/chemosensors13020046 - 3 Feb 2025
Cited by 2 | Viewed by 2236
Abstract
Potassium iodate and potassium iodide are commonly fortified in iodized table salt, which must be continuously monitored to maintain quality. Our study reported an optimized detection method for total iodine in iodized table salt using 0.5 M sodium bisulfite as the reducing agent. [...] Read more.
Potassium iodate and potassium iodide are commonly fortified in iodized table salt, which must be continuously monitored to maintain quality. Our study reported an optimized detection method for total iodine in iodized table salt using 0.5 M sodium bisulfite as the reducing agent. The iodized table salt (0.5 g) was dissolved in 0.5 M sodium bisulfite solution prior to injection in ultra-high-performance liquid chromatography (UHPLC) coupled with a diode array detector using a weak anion-exchange column (2.1 mm × 150 mm, 5 μm). Iodide was eluted at 9.92 ± 0.06 min (λ = 223 nm) when an isocratic mobile phase of 1:1 (v/v) methanol/120 mM phosphate buffer mixed with tetrasodium pyrophosphate (pH 3.0) was running at 0.20 mL/min (15 min). Iodide was detected as total iodine from 10.0 to 50.0 mg/kg with a limit of detection (LOD) of 1.2 mg/kg and a limit of quantification (LOQ) of 3.7 mg/kg. The method was validated with relative standard deviations (RSDs) of 4.2%, 0.4%, 1.6%, and 0.8% for accuracy, repeatability, intermediate precision, and robustness, respectively. The determination of total iodine was successful on six (6) samples (n = 3), which recovered 87.2–106.9% of iodate and iodide spike. Thus, this study provides a validated protocol for the determination of total iodine in iodized table salt using 0.5 M sodium bisulfite. Full article
(This article belongs to the Special Issue Green Analytical Chemistry: Current Trends and Future Developments)
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10 pages, 590 KB  
Article
Fingerprint Profile Analysis of Eupolyphaga steleophaga Polypeptide Based on UHPLC-MS and Its Application
by Xin Lai, Hongwei Song, Guangli Yan, Junling Ren and Xijun Wang
Pharmaceuticals 2025, 18(2), 166; https://doi.org/10.3390/ph18020166 - 26 Jan 2025
Viewed by 1586
Abstract
Background and Objectives: As a medicinal and food homologous substance, Eupolyphaga steleophaga is renowned for its potential health benefits, including anti-tumor effects, immune system support, and anti-inflammatory properties. Eupolyphaga steleophaga polypeptides have demonstrated significant biological activity, including the regulation of coagulation and lipid [...] Read more.
Background and Objectives: As a medicinal and food homologous substance, Eupolyphaga steleophaga is renowned for its potential health benefits, including anti-tumor effects, immune system support, and anti-inflammatory properties. Eupolyphaga steleophaga polypeptides have demonstrated significant biological activity, including the regulation of coagulation and lipid metabolism. However, the peptide composition of Eupolyphaga steleophaga requires further clarification to facilitate quality control improvements and a deeper investigation into its pharmacological effects. Therefore, this study aimed to simulate the digestive absorption process of Eupolyphaga steleophaga following oral administration and identify its enzymatic components to enhance quality control. Methods: The digestive absorption process was simulated using artificial gastric fluid and pepsin. A fingerprinting method based on ultrahigh-performance liquid chromatography-mass spectrometry (UHPLC-MS)(Acquire UPLC-Synapt G2-Si HDMS, Waters Corporation, Milford, MA, USA) was developed to identify 63 enzymatic components. The enzymolysis polypeptide fingerprint detection method was used to analyze 10 batches of Eupolyphaga steleophaga sourced from Harbin No. 4 Traditional Chinese Medicine Factory. Chromatographic collection was performed using an ACQUITY UPLC BHE C18 column. Gradient elution was carried out using a mixture of 0.1% formic acid with acetonitrile and 0.1% formic acid with water, with an average flow rate of 0.3 mL/min, a column temperature of 40 °C, and an injection volume of 2 μL. The mass spectrometry (MS) conditions were set as follows: the ion source was operated in positive electrospray ionization (ESI+) mode, with a capillary voltage of 2.8 kV and a sampling cone voltage of 40 V. The ion-source temperature was maintained at 110 °C, while the desolvation temperature was set to 400 °C. The cone gas flow rate was 50 L/h, and the desolvation gas flow rate was 800 L/h. The range for the collection of mass-to-charge ratios (m/z) was between 50 and 1200. Results: The UHPLC-MS method demonstrated high accuracy, repeatability, and stability, successfully identifying 63 enzymatic components of Eupolyphaga steleophaga. Furthermore, polypeptide markers for 63 selected components were identified in all 10 batches of Eupolyphaga steleophaga medicinal materials. This approach was validated by including numerical values such as retention times and peak areas, confirming its reliability for quality control enhancement. Conclusions: This novel UHPLC-MS approach serves as a powerful tool for advancing quality control strategies in veterinary medicine, particularly for animal-derived medicines. It lays a solid foundation for subsequent pharmacological studies of Eupolyphaga steleophaga polypeptides, offering a more reliable means to explore their biological activities and therapeutic potential. Full article
(This article belongs to the Section Natural Products)
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18 pages, 4159 KB  
Article
Ultrasonic Molding of Poly(3-hydroxybutyrate) and Its Clay Nanocomposites: Efficient Microspecimens Production with Minimal Material Loss and Degradation
by Germán Pérez, Anyi Jin, Luis J. del Valle, Enric Fontdecaba and Jordi Puiggalí
Appl. Sci. 2024, 14(24), 11959; https://doi.org/10.3390/app142411959 - 20 Dec 2024
Cited by 1 | Viewed by 931
Abstract
Ultrasound micromolding (USM) is an emerging processing technology that offers advantages with regard to spatial resolution, material savings, minimum time residence, minimum exposure to high temperatures, and low cost. Recent advances have been focused on nodal point technology, which improves the homogeneity of [...] Read more.
Ultrasound micromolding (USM) is an emerging processing technology that offers advantages with regard to spatial resolution, material savings, minimum time residence, minimum exposure to high temperatures, and low cost. Recent advances have been focused on nodal point technology, which improves the homogeneity of the molded samples and the repeatability of the properties of processed specimens. The present work demonstrates the suitability of a modified USM technology to process the biodegradable poly(3-hydroxybutyrate) (P3HB), which is a polymer that has well-reported difficulties when processed by conventional methods. Specifically, conventional injection, microinjection, and USM technologies with and without nodal point configurations have been compared. Degradation studies and the evaluation of thermal and mechanical properties confirmed the successful preparation of P3HB microspecimens, maintaining their functional integrity with minimal molecular weight loss. Exfoliated clay structures were observed for P3HB nanocomposites incorporating the C20 and C166 clays and processed by USM. The results highlight the advantages of the modified USM technology, as conventional microinjection failed to produce nanocomposites of P3HB/C116 due to the enhanced degradation caused by C116. Full article
(This article belongs to the Section Materials Science and Engineering)
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21 pages, 4842 KB  
Article
St. John’s Wort Extract Ze 117 and Escitalopram Alter Plasma and Hippocampal Lipidome in a Rat Model of Chronic-Stress-Induced Depression
by Hendrik Bussmann, Swen Bremer, Anne Marie Hernier, Jürgen Drewe, Hanns Häberlein, Sebastian Franken, Virginie Freytag, Georg Boonen and Veronika Butterweck
Int. J. Mol. Sci. 2024, 25(23), 12667; https://doi.org/10.3390/ijms252312667 - 26 Nov 2024
Viewed by 1827
Abstract
Chronic stress is a key factor in the development of depression. It leads to hyperactivation of the hypothalamic–pituitary–adrenal (HPA) axis, which in turn increases the formation of glucocorticoids (GCs). Chronically elevated GC levels disrupt neuroplasticity and affect brain lipid metabolism, which may, ultimately, [...] Read more.
Chronic stress is a key factor in the development of depression. It leads to hyperactivation of the hypothalamic–pituitary–adrenal (HPA) axis, which in turn increases the formation of glucocorticoids (GCs). Chronically elevated GC levels disrupt neuroplasticity and affect brain lipid metabolism, which may, ultimately, contribute to the development of depression. This study aimed to investigate the effects of the antidepressants St. John’s Wort extract and escitalopram on lipid metabolism in vivo. Therefore, repeated corticosterone injections were used to induce depression-like behavior in rats. Male Sprague–Dawley rats were stressed with corticosterone injections (40 mg/kg, s.c.) over 22 consecutive days and were concomitantly treated with varying doses of the St. John’s wort extract Ze 117 (30, 90 or 180 mg/kg, p.o.) or escitalopram (10 mg/kg, p.o.) and behavioral changes were evaluated using a modified forced swim test. The results indicate that repeated corticosterone injections significantly decreased the latency to first immobility. Furthermore, co-treatment of corticosterone with Ze 117 increased latency to first immobility significantly compared to rats treated with corticosterone alone. To further investigate the biochemical effects of corticosterone-induced stress, as well as the possible counter-regulation by antidepressants, the lipidomes of the plasma and hippocampus samples were analyzed by shotgun mass spectrometry. Corticosterone-induced stress significantly altered key lipid metabolites in the plasma but not in the hippocampal samples. In the hippocampus, however, specific glycerophospholipids such as lysophosphatidylethanolamines (LPEs) increased with escitalopram treatment and with Ze 117, both showing significant correlations with behavioral parameters. In summary, our study shows significant behavioral- and lipidome-altering processes with Ze 117 and escitalopram in rat plasma and hippocampal samples, thereby providing new targets and biomarker ideas for clinical diagnosis and antidepressant intervention. Full article
(This article belongs to the Special Issue Lipid Metabolism and Biomarkers in Neural and Cardiometabolic Health)
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Article
Stable Convergent Polyneuronal Innervation and Altered Synapse Elimination in Orbicularis oculi Muscles from Patients with Blepharospasm Responding Poorly to Recurrent Botulinum Type-A Neurotoxin Injections
by Brigitte Girard, Aurélie Couesnon, Emmanuelle Girard and Jordi Molgó
Toxins 2024, 16(12), 506; https://doi.org/10.3390/toxins16120506 - 24 Nov 2024
Cited by 1 | Viewed by 1903
Abstract
Botulinum neurotoxin type-A (BoNT/A), which blocks quantal acetylcholine (ACh) release at the neuromuscular junction (NMJ), has demonstrated its efficacy in the symptomatic treatment of blepharospasm. In 3.89% of patients treated for blepharospasm at Tenon Hospital, BoNT/A was no longer effective in relieving the [...] Read more.
Botulinum neurotoxin type-A (BoNT/A), which blocks quantal acetylcholine (ACh) release at the neuromuscular junction (NMJ), has demonstrated its efficacy in the symptomatic treatment of blepharospasm. In 3.89% of patients treated for blepharospasm at Tenon Hospital, BoNT/A was no longer effective in relieving the patient’s symptoms, and a partial upper myectomy of the Orbicularis oculi muscle was performed. We used surgical waste samples from 14 patients treated with repeated injections of either abobotulinumtoxinA (Dysport®) or incobotulinumtoxinA (Xeomin®). These muscle fragments were compared to others from 4 normal subjects, naïve of BoNT/A. The morphological study was performed blinded to the BoNT/A treatment and between treated and control samples. Neuromuscular specimens analyzed by confocal laser scanning microscopy, using fluorescent staining and immune-labeling of presynaptic proteins, revealed that the pattern of innervation (e.g., polyneuronal and convergent innervation), the muscle nicotinic ACh receptors (nAChRs), and the NMJs exhibited marked differences in BoNT/A-treated muscles (regardless of the toxin clinically used), with respect to controls. BoNT/A-treated junctions exhibited profuse polyneuronal innervation in which 2–6 axons innervated 74.84% of single muscle fibers, while 99.47% of control junctions were mono-innervated. Another new finding was the stable convergent innervation, in which several motor axons end onto the same endplate. Morphological signs of synapse elimination included the presence of retraction bulbs in axons and nerve terminals and a reduced extension of postsynaptic nAChRs. These outcomes suggest that synapse elimination is altered and raise questions on the origin and factors contributing to the plasticity changes observed and the functioning of NMJs. Full article
(This article belongs to the Special Issue Toxins: From the Wild to the Lab)
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