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1.
Angew Chem Int Ed Engl ; : e202408769, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38960984

ABSTRACT

The clinical application of photodynamic therapy (PDT) is limited by oxygen-dependence and side effects caused by photosensitizer residues. Photoinitiators based on the H-abstraction reaction can address these challenges because they can generate alkyl radical-killing cells independently of oxygen and undergo rapid bleaching following H-abstraction. Nonetheless, the development of photoinitiators for PDT has been impeded by the absence of effective design strategies. Herein, we have developed aryl-ketone substituted cyanine (ACy-R), the first red-light triggered H-abstraction photoinitiators for hypoxic cancer therapy. These ACy-R molecules inherited the near-infrared absorption of cyanine dye, and aryl-ketone modification imparted H-abstraction capability. Experimental and quantum calculations revealed that modifying the electron-withdrawing groups of the aryl (e.g., ACy-5F) improved the contribution of the O atom to the photon excitation process promoting intersystem crossing and H-abstraction ability. Particularly, ACy-5F rapidly penetrated cells and enriched in the endoplasmic reticulum. Even under severe hypoxia, ACy-5F initiated red-light induced H-abstraction with intracellular biomolecules, inducing necroptosis and ferroptosis. Moreover, ACy-5F was degraded after H-abstraction, thus avoiding the side effects of long-term phototoxicity after therapy. This study not only provides a crucial molecular tool for hypoxic tumors therapy, but also presents a promising strategy for the development of multifunctional photosensitizers and photoinitiators.

2.
Cancer Discov ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38975886

ABSTRACT

Cellular plasticity is a hallmark of pancreatic ductal adenocarcinoma (PDAC) starting from the conversion of normal cells into precancerous lesions, to the progression of carcinoma subtypes associated with aggressiveness and therapeutic response. We discovered that normal acinar cell differentiation, maintained by the transcription factor Pdx1, suppresses a broad gastric cell identity that is maintained in metaplasia, neoplasia, and the classical subtype of PDAC in mouse and human. We have identified the receptor tyrosine kinase Ror2 as marker of a gastric metaplasia-like identity in pancreas neoplasms. Ablation of Ror2 in a mouse model of pancreatic tumorigenesis promoted a switch to a gastric pit cell identity that largely persisted through progression to the classical subtype of PDAC. In both human and mouse pancreatic cancer, ROR2 activity continued to antagonize the gastric pit cell identity, strongly promoting an epithelial to mesenchymal transition, conferring resistance to KRAS inhibition, and vulnerability to AKT inhibition.

3.
Nano Lett ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38967611

ABSTRACT

Stabilization of multiple polarization states at the atomic scale is pivotal for realizing high-density memory devices beyond prevailing bistable ferroelectric architectures. Here, we show that two-dimensional ferroelectric SnS or GeSe is able to revive and stabilize the ferroelectric order of three-dimensional ferroelectric BaTiO3, even when the latter is thinned to one unit cell in thickness. The underlying mechanism for overcoming the conventional detrimental critical thickness effect is attributed to facile interfacial inversion symmetry breaking by robust in-plane polarization of SnS or GeSe. Furthermore, when invoking interlayer sliding, we can stabilize multiple polarization states and achieve efficient interstate switching in the heterostructures, accompanied by dynamical ferroelectric skyrmionic excitations. When invoking sliding and twisting, the moiré domains exhibit nontrivial polar vortexes, which can be laterally displaced via different sliding schemes. These findings provide an intuitive avenue for simultaneously overcoming the standing critical thickness issue in bulk ferroelectrics and weak polarization issue in sliding ferroelectricity.

4.
NPJ Biofilms Microbiomes ; 10(1): 49, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38902244

ABSTRACT

Helicobacter pylori is a prevalent bacterial pathogen globally, implicated in various gastrointestinal disorders. Current recommended antibiotic therapies for H. pylori infection have been proven to be therapeutically insufficient, with low eradication rates and high recurrence rates. Emerging evidence suggests that antibiotic therapy for H. pylori can lead to gastrointestinal and subsequent vaginal dysbiosis, posing challenges for conventional antibiotic approaches. Thus, this article proposes a novel probiotic therapy involving simultaneous oral and intra-vaginal probiotic administration alongside antibiotics for H. pylori treatment, aiming to enhance eradication rates and mitigate dysbiosis. We begin by providing an overview of gastrointestinal and vaginal microbiota and their interconnectedness through the vagina-gut axis. We then review the efficacy of current antibiotic regimens for H. pylori and discuss how antibiotic treatment impacts the vaginal microenvironment. To explore the feasibility of this approach, we evaluate the effectiveness of oral and intra-vaginal probiotics in restoring normal microbiota in the gastrointestinal and vaginal tracts, respectively. Additionally, we analyze the direct mechanisms by which oral and intra-vaginal probiotics act on their respective tracts and discuss potential cross-tract mechanisms. Considering the potential synergistic therapeutic effects of probiotics in both the gastrointestinal and vaginal tracts, dual-channel probiotic therapy holds promise as a more effective approach for H. pylori eradication and dysbiosis mitigation, presenting a novel concept in the collaborative treatment of gastrointestinal and genital disorders.


Subject(s)
Anti-Bacterial Agents , Dysbiosis , Helicobacter Infections , Helicobacter pylori , Probiotics , Vagina , Probiotics/administration & dosage , Female , Humans , Dysbiosis/therapy , Anti-Bacterial Agents/administration & dosage , Helicobacter Infections/drug therapy , Helicobacter Infections/therapy , Helicobacter Infections/microbiology , Vagina/microbiology , Vagina/drug effects , Helicobacter pylori/drug effects , Administration, Intravaginal , Administration, Oral
5.
J Mater Chem B ; 12(25): 6102-6116, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38836422

ABSTRACT

Physical eutectogels as a newly emerging type of conductive gel have gained extensive interest for the next generation multifunctional electronic devices. Nevertheless, some obstacles, including weak mechanical performance, low self-adhesive strength, lack of self-healing capacity, and low conductivity, hinder their practical use in wearable strain sensors. Herein, lignin as a green filler and a multifunctional hydrogen bond donor was directly dissolved in a deep eutectic solvent (DES) composed of acrylic acid (AA) and choline chloride, and lignin-reinforced physical eutectogels (DESL) were obtained by the polymerization of AA. Due to the unique features of lignin and DES, the prepared DESL eutectogels exhibit good transparency, UV shielding capacity, excellent mechanical performance, outstanding self-adhesiveness, superior self-healing properties, and high conductivity. Based on the aforementioned integrated functions, a wearable strain sensor displaying a wide working range (0-1500%), high sensitivity (GF = 18.15), rapid responsiveness, and excellent stability and durability (1000 cycles) and capable of detecting diverse human motions was fabricated. Additionally, by combining DESL sensors with a deep learning technique, a gesture recognition system with accuracy as high as 98.8% was achieved. Overall, this work provides an innovative idea for constructing multifunction-integrated physical eutectogels for application in wearable electronics.


Subject(s)
Deep Learning , Wearable Electronic Devices , Humans , Gels/chemistry , Lignin/chemistry , Acrylates/chemistry , Electric Conductivity , Choline/chemistry , Particle Size , Deep Eutectic Solvents/chemistry
6.
Surg Endosc ; 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886230

ABSTRACT

BACKGROUND: Missed early gastric cancer (MEGC) is prevalent during esophagogastroduodenoscopy (EGD), which is the first-line recommended strategy for detecting early gastric cancer (EGC). Hence, we explored the risk factors for MEGC and different types of MEGC, based on the endoscopic resected population. METHODS: This retrospective, case-control study was conducted at Nanjing Drum Tower Hospital (NJDTH). We included patients who were diagnosed with EGC during screening EGD, underwent endoscopic resection, and were confirmed by postoperative pathology at the NJDTH from January 2014 to December 2021, and classified them into different types according to the different root causes of misses. Univariable, multivariable, subgroup and propensity score analyses were used to explore the risk factors for MEGC and different types of MEGC. RESULTS: A total of 447 patients, comprising 345 with initially detected early gastric cancer (IDEGC) and 102 with MEGC, were included in this study. Larger size (≥ 1 cm) (OR 0.45, 95% CI 0.27-0.74, P = 0.002) and invasion depth of submucosa (OR 0.26, 95% CI 0.10-0.69, P = 0.007) were negatively associated with MEGC. Use of sedation (OR 0.32, 95% CI 0.20-0.52, P < 0.001) and longer observation time (OR 0.60, 95% CI 0.37-0.96, P = 0.034) exhibited protective effect on MEGC. CONCLUSIONS: Smaller and more superficial EGC lesions are more susceptible to misdiagnosis. The use of sedation and prolonged observation time during EGD could help reduce the occurrence of MEGC.

7.
Sci Rep ; 14(1): 13152, 2024 06 07.
Article in English | MEDLINE | ID: mdl-38849408

ABSTRACT

To assess the effectiveness and safety of combining Saccharomyces boulardii powder with triple therapy as a primary approach for eradicating H. pylori infection, a total of 144 patients who tested positive for H. pylori and diagnosed with non-ulcer dyspepsia underwent endoscopy at two national centers between June 2017 and March 2019 were included. The patients were categorized into three groups using a subsection randomization method and received initial H. pylori eradication treatments. Microbial composition, eradication rates, symptom alleviation, and adverse reactions were monitored on the 14th and 44th days post-treatment. According to PP analysis showed the eradication rates for the SRAC group was 75%, BRAC was 93.18% and RAC was 65.2%. Group BRAC exhibited a marginally higher eradication rate compared to other groups. However, patients receiving Saccharomyces boulardii treatment exhibited an overall reduction in initial dyspepsia symptoms by the end of the treatment period. When employed as a primary strategy, the combination of Saccharomyces boulardii powder with triple therapy displayed notable efficacy and smaller gastrointestinal side effects in eradicating initial H. pylori infections among non-ulcer dyspepsia patients. Moreover, this approach demonstrated advantages in alleviating symptoms, exhibited favorable tolerance, and maintained a high level of clinical safety.


Subject(s)
Drug Therapy, Combination , Dyspepsia , Helicobacter Infections , Helicobacter pylori , Probiotics , Saccharomyces boulardii , Humans , Helicobacter Infections/therapy , Helicobacter Infections/drug therapy , Male , Female , Helicobacter pylori/drug effects , Middle Aged , Probiotics/administration & dosage , Probiotics/therapeutic use , Dyspepsia/microbiology , Dyspepsia/therapy , Adult , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/administration & dosage , Gastrointestinal Microbiome , Treatment Outcome , Proton Pump Inhibitors/therapeutic use , Proton Pump Inhibitors/administration & dosage , Aged , Amoxicillin/therapeutic use , Amoxicillin/administration & dosage
8.
Chem Asian J ; : e202400389, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38865098

ABSTRACT

Intrinsically disordered protein regions (IDPRs) are pivotal in the regulation of transcription and the facilitation of signal transduction. Because of their multiple conformational states of structure, characterizing the highly flexible structures of IDPRs becomes challenging. Herein, we employed the wild-type (WT) aerolysin nanopore as a real-time biosensor for the identification and monitoring of long peptides containing IDPRs. This sensor successfully identified three intrinsically disordered peptides, with the lengths up to 43 amino acids, by leveraging the unique signatures of blockade current and translocation duration time. The analysis of the binding constant revealed that interactions between the nanopore and peptide are critical for peptide translocation, suggesting that mechanisms beyond mere volume exclusion are at play. Furthermore, by examining the detailed current traces of blockade events, we were able to compare the conformational stabilities of various IDPRs. Our approach can detect the conformational changes of IDPR in a confined nanopore space. These insights broaden the understanding of peptide structural changes under the confined space. This nanopore biosensor showed the potential to study the conformations change of IDPRs, IDPRs transmembrane interactions, and protein drug discovery.

9.
Nat Commun ; 15(1): 4784, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38839772

ABSTRACT

Two-dimensional topological insulators hosting the quantum spin Hall effect have application potential in dissipationless electronics. To observe the quantum spin Hall effect at elevated temperatures, a wide band gap is indispensable to efficiently suppress bulk conduction. Yet, most candidate materials exhibit narrow or even negative band gaps. Here, via elegant control of van der Waals epitaxy, we have successfully grown monolayer ZrTe5 on a bilayer graphene/SiC substrate. The epitaxial ZrTe5 monolayer crystalizes in two allotrope isomers with different intralayer alignments of ZrTe3 prisms. Our scanning tunneling microscopy/spectroscopy characterization unveils an intrinsic full band gap as large as 254 meV and one-dimensional edge states localized along the periphery of the ZrTe5 monolayer. First-principles calculations further confirm that the large band gap originates from strong spin-orbit coupling, and the edge states are topologically nontrivial. These findings thus provide a highly desirable material platform for the exploration of the high-temperature quantum spin Hall effect.

10.
Sci Rep ; 14(1): 14226, 2024 06 20.
Article in English | MEDLINE | ID: mdl-38902401

ABSTRACT

This study aimed to investigate impacts of Omicron infection on cancer patients in China. A retrospective study was conducted, including 347 cancer patients undergoing radiotherapy or chemoradiotherapy between July 2022 and March 2023. Three groups involved: 108 patients without SARS-CoV-2 infection (non-COVID-19 group), 102 patients beginning treatment 10 days after first SARS-CoV-2 infection (≥ 10 days COVID-19 group), and 137 patients beginning treatment less than 10 days after first SARS-CoV-2 infection (< 10 days COVID-19 group). SAA, hsCRP, ALT, etc., were used to assess COVID-19 infection. Serum levels of SAA, hsCRP and IL-6 were all raised in two COVID-19-infected groups (SAA < 0.01, hsCRP < 0.01, IL-6 < 0.05), but PCT, ALT, LDH and HBDH levels were only elevated in ≥ 10 days COVID-19 group (PCT = 0.0478, ALT = 0.0022, LDH = 0.0313, HBDH = 0.0077). Moreover, moderate and severe infected cases were higher in ≥ 10 days COVID-19 group than < 10 days COVID-19 group (12/102 vs 5/137, p = 0.0211), but no significance in myelosuppression and completion rates among three groups. Omicron infection led to inflammation, liver and cardiovascular injury on cancer patients, but delay duration of radiotherapy or chemoradiotherapy after infection did not affect the completion rates and myelosuppression of current therapy. Besides, severity of Omicron infection was even worse among cancer patients who received delayed treatment.


Subject(s)
COVID-19 , Chemoradiotherapy , Neoplasms , SARS-CoV-2 , Humans , COVID-19/therapy , Female , Male , Middle Aged , Neoplasms/radiotherapy , Neoplasms/therapy , Neoplasms/drug therapy , Chemoradiotherapy/adverse effects , Retrospective Studies , Aged , SARS-CoV-2/isolation & purification , Adult , China/epidemiology
11.
Sci Total Environ ; 940: 173526, 2024 Aug 25.
Article in English | MEDLINE | ID: mdl-38825199

ABSTRACT

BACKGROUND: Chronic rhinosinusitis (CRS) is a prevalent upper respiratory condition that manifests in two primary subtypes: CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). While previous studies indicate a correlation between air pollution and CRS, the role of genetic predisposition in this relationship remains largely unexplored. We hypothesized that higher air pollution exposure would lead to the development of CRS, and that genetic susceptibility might modify this association. METHODS: This cohort study involving 367,298 adult participants from the UK Biobank, followed from March 2006 to October 2021. Air pollution metrics were estimated at residential locations using land-use regression models. Cox proportional hazard models were employed to explore the associations between air pollution exposure and CRS, CRSwNP, and CRSsNP. A polygenic risk score (PRS) was constructed to evaluate the joint effect of air pollution and genetic predisposition on the development of CRS. RESULTS: We found that the risk of CRS increased under long-term exposure to PM2.5 [the hazard ratios (HRs) with 95 % CIs: 1.59 (1.26-2.01)], PM10 [1.64 (1.26-2.12)], NO2 [1.11 (1.04-1.17)], and NOx [1.18 (1.12-1.25)], respectively. These effects were more pronounced among participants with CRSwNP, although the differences were not statistically significant. Additionally, we found that the risks for CRS and CRSwNP increased in a graded manner among participants with higher PRS or higher exposure to PM2.5, PM10, or NOx concentrations. However, no multiplicative or additive interactions were observed. CONCLUSIONS: Long-term exposure to air pollution increases the risk of CRS, particularly CRSwNP underscoring the need to prioritize clean air initiatives and environmental regulations.


Subject(s)
Air Pollution , Biological Specimen Banks , Rhinitis , Sinusitis , Humans , Air Pollution/statistics & numerical data , Air Pollution/adverse effects , Sinusitis/epidemiology , United Kingdom/epidemiology , Rhinitis/epidemiology , Chronic Disease , Prospective Studies , Male , Middle Aged , Female , Air Pollutants/analysis , Environmental Exposure/statistics & numerical data , Adult , Genetic Predisposition to Disease , Aged , Particulate Matter , Nasal Polyps/epidemiology , Nasal Polyps/genetics , Rhinosinusitis , UK Biobank
13.
ACS Nano ; 18(26): 16413-16449, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38904346

ABSTRACT

Layered double hydroxides (LDHs), especially those containing nickel (Ni), are increasingly recognized for their potential in photo(-/)electrocatalytic water oxidation due to the abundant availability of Ni, their corrosion resistance, and their minimal toxicity. This review provides a comprehensive examination of Ni-based LDHs in electrocatalytic (EC), photocatalytic (PC), and photoelectrocatalytic (PEC) water oxidation processes. The review delves into the operational principles, highlighting similarities and distinctions as well as the benefits and limitations associated with each method of water oxidation. It includes a detailed discussion on the synthesis of monolayer, ultrathin, and bulk Ni-based LDHs, focusing on the merits and drawbacks inherent to each synthesis approach. Regarding the EC oxygen evolution reaction (OER), strategies to improve catalytic performance and insights into the structural evolution of Ni-based LDHs during the electrocatalytic process are summarized. Furthermore, the review extensively covers the advancements in Ni-based LDHs for PEC OER, including an analysis of semiconductors paired with Ni-based LDHs to form photoanodes, with a focus on their enhanced activity, stability, and underlying mechanisms facilitated by LDHs. The review concludes by addressing the challenges and prospects in the development of innovative Ni-based LDH catalysts for practical applications. The comprehensive insights provided in this paper will not only stimulate further research but also engage the scientific community, thus driving the field of photo(-/)electrocatalytic water oxidation forward.

14.
Breast Cancer Res Treat ; 207(1): 187-201, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38750271

ABSTRACT

PURPOSE: HER2-positive breast cancer (BC) accounts for 20-30% of all BC subtypes and is linked to poor prognosis. Trastuzumab (Tz), a humanized anti-HER2 monoclonal antibody, is a first-line treatment for HER2-positive breast cancer which faces resistance challenges. This study aimed to identify the biomarkers driving trastuzumab resistance. METHODS: Differential expression analysis of genes and proteins between trastuzumab-sensitive (TS) and trastuzumab-resistant (TR) cells was conducted using RNA-seq and iTRAQ. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) were used to study their functions. The prognostic significance and protein levels of ARFIP2 and MSN were evaluated using online tools and immunohistochemistry. Sensitivity of MSN and ARFIP2 to other therapies was assessed using public pharmacogenomics databases and the R language. RESULTS: Five genes were up-regulated, and nine genes were down-regulated in TR cells at both transcriptional and protein levels. Low ARFIP2 and high MSN expression linked to poor BC prognosis. MSN increased and ARFIP2 decreased in TR patients, correlating with shorter OS. MSN negatively impacted fulvestrant and immunotherapy sensitivity, while ARFIP2 had a positive impact. CONCLUSION: Our findings suggest that MSN and ARFIP2 could serve as promising biomarkers for predicting response to Tz, offering valuable insights for future research in the identification of diagnostic and therapeutic targets for BC patients with Tz resistance.


Subject(s)
Biomarkers, Tumor , Breast Neoplasms , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Proteome , Transcriptome , Trastuzumab , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/mortality , Drug Resistance, Neoplasm/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Trastuzumab/therapeutic use , Trastuzumab/pharmacology , Prognosis , Gene Expression Profiling/methods , Proteomics/methods , Cell Line, Tumor , Antineoplastic Agents, Immunological/therapeutic use , Antineoplastic Agents, Immunological/pharmacology , Repressor Proteins/genetics , Repressor Proteins/metabolism , Receptor, ErbB-2/metabolism , Receptor, ErbB-2/genetics
15.
ACS Nano ; 18(23): 15025-15034, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38804641

ABSTRACT

Iontronics that are capable of mimicking the functionality of biological systems within an artificial fluidic network have long been pursued for biomedical applications and ion-based intelligence systems. Here, we report on facile and robust realization of iontronic bipolar memristors featuring a three-layer polyelectrolyte gel structure. Significant memristive hysteresis of ion currents was successfully accomplished, and the memory time proved geometrically scalable from 200 to 4000 s. These characteristics were enabled by the ion concentration polarization-induced rectification ratio within the polyelectrolyte gels. The memristors exhibited memory dynamics akin to those observed in unipolar devices, while the bipolar structure notably enabled prolonged memory time and enhanced the ion conductance switching ratio with mesoscale (10-1000 µm) geometry precision. These properties endow the devices with the capability of effective neuromorphic processing with pulse-based input voltage signals. Owing to their simple fabrication process and superior memristive performance, the presented iontronic bipolar memristors are versatile and can be easily integrated into small-scale iontronic circuits, thereby facilitating advanced neuromorphic computing functionalities.

16.
Pediatrics ; 153(6)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38742313

ABSTRACT

OBJECTIVES: Establish the longitudinal cross-lagged associations between maltreatment exposure and child behavior problems to promote screening and the type and timing of interventions needed. METHODS: The Longitudinal Studies of Child Abuse and Neglect, a multiwave prospective cohort study of maltreatment exposure, enrolled children and caregivers (N = 1354) at approximately age 4 and followed them throughout childhood and adolescence. Families completed 7 waves of data collection with each wave occurring 2 years apart. Maltreatment was confirmed using official case records obtained from Child Protective Services. Six-month frequencies of behavior problems were assessed via caregiver-report. Two random-intercept, cross-lagged panel models tested the directional relations between maltreatment exposure and externalizing and internalizing behaviors. RESULTS: Maltreatment exposure predicted increases in externalizing behaviors at ages 8 (b = 1.06; 95% confidence interval [CI] 0.14-1.98), 12 (b = 1.09; 95% CI 0.08-2.09), and 16 (b = 1.67; 95% CI 0.30-3.05) as well as internalizing behaviors at ages 6 (b = 0.66; 95% CI 0.03-1.29), 12 (b = 1.25; 95% CI 0.33-2.17), and 14 (b = 1.92; 95% CI 0.76-2.91). Increases in externalizing behaviors predicted maltreatment exposure at age 12 (odds ratio 1.02; 95% CI 1.00-1.05). CONCLUSIONS: Maltreatment exposure is robustly associated with subsequent child behavior problems, strengthening inferences about the directionality of these relations. Early screening of externalizing behaviors in pediatric settings can identify children likely to benefit from intervention to reduce such behaviors as well as prevent maltreatment exposure at entry to adolescence.


Subject(s)
Child Abuse , Child Behavior Disorders , Humans , Child , Male , Female , Child Abuse/psychology , Child Abuse/statistics & numerical data , Child, Preschool , Adolescent , Child Behavior Disorders/epidemiology , Child Behavior Disorders/etiology , Child Behavior Disorders/psychology , Prospective Studies , Longitudinal Studies , Problem Behavior/psychology
17.
J Pharm Biomed Anal ; 246: 116236, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38772203

ABSTRACT

As the adulteration of dietary supplements with synthetic drugs remains a prevalent issue, the inclusion of anti-obesity agents may pose health risks, potentially leading to central nervous system or cardiovascular diseases. However, surveillance studies on the use of anti-obesity agents by the Chinese population are limited. This study aims to establish an efficient and rapid hair pretreatment method using dispersive liquid-liquid microextraction (DLLME) combined with high-speed grinding and develop a sensitive and accurate analytical method employing ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for detecting 13 potential anti-obesity agents in hair samples. Herein, hair samples were washed sequentially with 0.1% sodium dodecyl sulfate (SDS), water and acetone, and then ground at high speed using 1 mL of an extraction solution (internal standard solution-n-butanol-1.2 mol/L Na2HPO4, pH10.0, 100:400:500, v/v/v for procaterol; internal standard solution-ethyl acetate-1.2 mol/L Na2HPO4, pH8.0, 100:300:600, v/v/v for other 12 anti-obesity agents) while simultaneously performing DLLME. The developed method successfully detected 13 anti-obesity agents within 11 min, including bambuterol, clenbuterol, ractopamine, clorprenaline, formoterol, salbutamol, terbutaline, procaterol, phentermine, bupropion, sibutramine, desmethyl sibutramine, and N,N-didesmethyl sibutramine, which improved the screening efficiency. The calibration curves exhibited good linearity of 0.025-5 ng/mg, achieving correlation coefficients of r ≥ 0.99. The lower limits of quantification (LLOQs) for the analytes were 0.025 ng/mg, demonstrating acceptable levels of accuracy and precision. Recovery rates ranged between 73.30% and 107.47% across the three concentrations of 0.075, 0.375, and 3.75 ng/mg. The validated method was successfully applied to 369 real cases and detected six analytes, including bambuterol, salbutamol, terbutaline, sibutramine, desmethyl sibutramine, and N,N-didesmethyl sibutramine. This method offers several advantages, including simple pretreatment, high extraction efficiency, rapid extraction, solvent economy, and pollution mitigation, making it highly suitable for large-scale surveillance of usage of added anti-obesity agents.


Subject(s)
Anti-Obesity Agents , Hair , Liquid Phase Microextraction , Tandem Mass Spectrometry , Tandem Mass Spectrometry/methods , Anti-Obesity Agents/analysis , Liquid Phase Microextraction/methods , Chromatography, High Pressure Liquid/methods , Hair/chemistry , Humans , Limit of Detection , Reproducibility of Results
18.
J Environ Manage ; 360: 121104, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38733845

ABSTRACT

Excess nitrogen (N) discharged into streams and rivers degrades freshwater quality and threatens ecosystems worldwide. Land use patterns may influence riverine N export, yet the effect of location on N export and removal is not fully understood. We proposed a hybrid model to analyze N export and removal within the watersheds. The proposed model is satisfied for the riverine N modelling. The KGE and R2 are 0.75 and 0.72 in the calibration period which are 0.76 and 0.61 in the validation period. Human-impacted land use may modify the N yield in the watershed, and the net N export from built-up to the in-stream system was highest in the urbanized sub-watersheds (0.81), followed by the agricultural sub-watersheds (0.88), and forested sub-watersheds (0.96). Agricultural activities make a large contribution to the N exports in the watersheds, and the mean N input from the agricultural land use to in-stream were 2069-4353 kg km-2 yr-1. Besides, the excess inputs of N by overapplication of fertilizer and manure during the agricultural activities may increase legacy N in soil and groundwater. Biological processes for the riverine N removal may be controlled by the available substrate in the freshwater system, and temperature sensitivity of denitrification is highest in the flood seasons, especially for the human-impacted sub-watersheds. The riverine biological processes may be limited by other competitions. Our model results provide evidence that quantity and location of specific land use may control biogeochemistry within watersheds. We demonstrate the need to understand nutrient export and removal within watersheds by improving the representation of spatial patterns in existing watershed models, and we consider this study to be a new effort for the spatially explicit modeling to support land-use based N management in watersheds.


Subject(s)
Agriculture , Nitrogen , Rivers , Nitrogen/analysis , Rivers/chemistry , Models, Theoretical , Ecosystem , Nutrients/analysis , Environmental Monitoring
19.
Materials (Basel) ; 17(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38730807

ABSTRACT

CeO2 is widely used in the field of chemical-mechanical polishing for integrated circuits. Morphology, particle size, crystallinity, and Ce3+ concentration are crucial factors that affect polishing performance. In this study, we successfully synthesized two novel triangular CeO2 abrasives with similar particle sizes (600 nm) but different morphologies and Ce3+ concentrations using a microwave-assisted hydrothermal method with high-concentration raw materials, and no surfactants or template agents were added. It is generally believed that CeO2 with a higher Ce3+ concentration leads to better polishing performance. However, the results of polishing indicate that CeO2 synthesized at 200 °C, despite its lower Ce3+ concentration, demonstrates outstanding polishing performance, achieving a polishing rate of 324 nm/min, and the Sa of Si wafers decreased by 3.6% after polishing. This suggests that, under similar particle size conditions, the morphology of CeO2 plays a dominant role in the mechanical effects during the polishing process. Additionally, compared to commercial polishing slurries, the synthesized samples demonstrated better polishing performance. This indicates that, in CMP, the pursuit of smaller spherical abrasives may not be necessary. Instead, the appropriate shape and particle size can better balance the material removal rate and surface roughness.

20.
Carbohydr Polym ; 337: 122085, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38710579

ABSTRACT

Microfibrillated cellulose (MFC) is a bio-material produced by disintegrating cellulose fibres into fibrillar components. MFC could offer a sustainable solution to packaging needs since it can form an excellent barrier to oxygen. However, a comprehensive understanding of how MFC characteristics impact barrier properties of MFC films or coatings is required. This article critically reviews how the extent of separation of fibres into fibrils-and any resulting changes to the crystallinity and degree of polymerisation of cellulose-influences gas barrier properties of MFC films or coatings. Findings from publications investigating the barrier performance of MFC prepared through different processes intending to increase the effectiveness of fibrillation are evaluated and compared. The effects of processing conditions or chemical pre-treatments on barrier properties of MFC films or coatings are then discussed. A comparison of reported results showed that morphology and size polydispersity of the cellulose strongly influence the barrier properties of MFC. However, changing the MFC production process to decrease fibril diameter and polydispersity can result in changes to cellulose crystallinity; reduction in fibril length; introduction of bulky functional groups; or increased fibril surface charge: all of which could have a negative impact on the barrier properties of the final films or coatings.

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