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Electrolytic hydrogen production via water splitting holds significant promise for the future of the energy revolution. The design of efficient and abundant catalysts, coupled with a comprehensive understanding of the hydrogen evolution reaction (HER) mechanism, is of paramount importance. In this study, we propose a strategy to craft an atomically precise cluster catalyst with superior HER performance by cocoupling a Mo2O4 structural unit and a Cu(I) alkynyl cluster into a structured framework. The resulting bimetallic cluster, Mo2Cu17, encapsulates a distinctive structure [Mo2O4Cu17(TC4A)4(PhC≡C)6], comprising a binuclear Mo2O4 subunit and a {Cu17(TC4A)2(PhC≡C)6} cluster, both shielded by thiacalix[4]arene (TC4A) and phenylacetylene (PhC≡CH). Expanding our exploration, we synthesized two homoleptic CuI alkynyl clusters coprotected by the TC4A and PhC≡C- ligands: Cu13 and Cu22. Remarkably, Mo2Cu17 demonstrates superior HER efficiency compared to its counterparts, achieving a current density of 10 mA cm-2 in alkaline solution with an overpotential as low as 120 mV, significantly outperforming Cu13 (178 mV) and Cu22 (214 mV) nanoclusters. DFT calculations illuminate the catalytic mechanism and indicate that the intrinsically higher activity of Mo2Cu17 may be attributed to the synergistic Mo2O4-Cu(I) coupling.
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An imidazolyl hydrogen-bonded organic framework (HOF-T) with outstanding thermal and water stability was constructed by C-Hâ¯N hydrogen bonding and C-Hâ¯π interactions. UO22+ can be selectively captured by the imidazole group of HOF-T and rapidly reduced to UO2 under visible light irradiation, realizing exceptional uranium removal with high capacity and fast kinetics.
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Untreated radioactive iodine (129I and 131I) released from nuclear power plants poses a significant threat to humans and the environment, so the development of materials to capture iodine from water media and steam is critical. Here, we report a charge transfer complex (TCNQ-MA CTC) with abundant nitrogen atoms and π-conjugated system for adsorption of I2 vapor and I3- from aqueous solutions. Due to the synergistic binding mechanism of benzene/triazine rings and N-containing groups with iodine, special I-π and charge transfer interaction can be formed between the guest and the host, and thus efficient removal of I2 and I3- can be realized by TCNQ-MA CTC with the adsorption capacity up to 2.42 g/g and 800 mg/g, respectively. TCNQ-MA CTC can capture 92% of I3- within 2.5 min, showing extremely fast kinetics, excellent selectivity and high affinity (Kd = 5.68 × 106 mL/g). Finally, the TCNQ-MA CTC was successfully applied in the removal of iodine from seawater with the efficiency of 93.71%. This work provides new insights in the construction of charge transfer complexes and lays the foundation for its environmental applications.
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BACKGROUND: Individuals with mild cognitive impairment are at high risk of developing dementia. Dance therapy has promising applications in delaying cognitive decline. However, the effectiveness of dance therapy for older adults with mild cognitive impairment is unclear. The objective of this review was to evaluate the effectiveness of dance therapy on global cognitive function, specific cognitive subdomains, quality of life, and mental health in older adults with mild cognitive impairment to enrich health management strategies for dementia. METHODS: Electronic databases and grey literature were searched from inception up to September 23, 2023. The language was limited to English and Chinese. Relevant studies were screened and assessed for risk of bias. A meta-analysis and subgroup analyses stratified by measurement instrument, dance type, intervention duration, and frequency were conducted using the STATA 16.0 software. This review was conducted in accordance with the PRISMA guidelines. RESULTS: Ten studies involving 984 participants aged 55 years and over who met the eligibility criteria were included. Dance therapy significantly improved global cognitive function, memory, executive function, attention, language, and mental health (i.e., depression and neuropsychiatric symptoms). However, the effects of dance therapy on processing speed, visuospatial ability, and quality of life in older adults with mild cognitive impairment remain inconclusive. Moreover, dance interventions of longer duration (> 3 months) improved global cognition more than shorter interventions. CONCLUSION: This review reported that dance therapy was effective in improving global cognitive function, memory, executive function, attention, language, and mental health (i.e., depression and neuropsychiatric symptoms). Hence, it may be an effective non-pharmacological complementary treatment for older adults with mild cognitive impairment.
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Disfunción Cognitiva , Danzaterapia , Demencia , Humanos , Anciano , Salud Mental , Calidad de Vida , Disfunción Cognitiva/terapia , CogniciónRESUMEN
Nanocluster catalysts face a significant challenge in striking the right balance between stability and catalytic activity. Here, we present a thiacalix[4]arene-protected 6-electron [Ag30(TC4A)4(iPrS)8] nanocluster that demonstrates both high stability and catalytic activity. The Ag30 nanocluster features a metallic core, Ag104+, consisting of two Ag3 triangles and one Ag4 square, shielded by four {Ag5@(TC4A)4} staple motifs. Based on DFT calculations, the Ag104+ metallic kernel can be viewed as a trimer comprising 2-electron superatomic units, exhibiting a valence electron structure similar to that of the Be3 molecule. Notably, this is the first crystallographic evidence of the trimerization of 2-electron superatomic units. Ag30 can reduce CO2 into CO with a Faraday efficiency of 93.4% at -0.9 V versus RHE along with excellent long-term stability. Its catalytic activity is far superior to that of the chain-like AgI polymer ∞1{[H2Ag5(TC4A)(iPrS)3]} (∞1Agn), with the composition similar to Ag30. DFT calculations elucidated the catalytic mechanism to clarify the contrasting catalytic performances of the Ag30 and ∞1Agn polymers and disclosed that the intrinsically higher activity of Ag30 may be due to the greater stability of the dual adsorption mode of the *COOH intermediate on the metallic core.
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Hyperplasia of mammary glands is a benign breast disease with disordered breast structure. Nowadays, the incidence rate of breast hyperplasia in women is increasing year by year, and the etiology is related to the imbalance of estrogen and progesterone in the body. The symptoms include breast pain, breast nodules, or nipple discharge, which can develop into breast cancer in the context of psychological pressure. Therefore, it is timely and effectively necessary for people to treat the symptoms. At present, traditional Chinese medicine(TCM) often treats breast hyperplasia by oral drug, external application, acupuncture, moxibustion, and massage, while western medicine often uses hormone therapy or surgery. TCM can regulate hormone levels to treat breast hyperplasia. Acupuncture, moxibustion, and other methods can stimulate acupoints to reduce breast lumps. However, since TCM is easy to produce hepatorenal toxicity after long-term use and simple external treatment is slow to take effect, rapid and effective treatment is difficult to be achieved. Although western medicine can inhibit the disease, it is easy to produce toxic and side effects if taken for a long time. In addition, surgery can only remove the focus and the recurrence rate is high. Some studies have found that the combination of oral and external use of TCM compounds has a significant effect, with mild toxic and side effects, few adverse reactions, and a low recurrence rate. Based on the relevant literature in recent years, this article reviewed the combination of oral and external treatment of TCM in the treatment of hyperplasia of mammary glands, discussed the effectiveness, clinical evaluation indexes, and mechanism, and pointed out the existing shortcomings to explore a comprehensive therapy worthy of clinical application.
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Terapia por Acupuntura , Neoplasias de la Mama , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Glándulas Mamarias Humanas , Femenino , Humanos , Medicina Tradicional China , Hiperplasia , EstrógenosRESUMEN
BACKGROUND: New drugs are urgently needed for the treatment of liver cancer, a feat that could be feasibly accomplished by finding new therapeutic purposes for marketed drugs to save time and costs. As a new class of national anti-infective drugs, carrimycin (CAM) has strong activity against gram-positive bacteria and no cross resistance with similar drugs. Studies have shown that the components of CAM have anticancer effects. AIM: To obtain a deeper understanding of CAM, its distribution, metabolism and anti-inflammatory effects were assessed in the organs of mice, and its mechanism of action against liver cancer was predicted by a network pharmacology method. METHODS: In this paper, the content of isovaleryl spiramycin III was used as an index to assess the distribution and metabolism of CAM and its effect on inflammatory factors in various mouse tissues and organs. Reverse molecular docking technology was utilized to determine the target of CAM, identify each target protein based on disease type, and establish a target protein-disease type network to ascertain the effect of CAM in liver cancer. Then, the key action targets of CAM in liver cancer were screened by a network pharmacology method, and the core targets were verified by molecular docking and visual analyses. RESULTS: The maximum CAM concentration was reached in the liver, kidney, lung and spleen 2.5 h after intragastric administration. In the intestine, the maximum drug concentration was reached 0.5 h after administration. In addition, CAM significantly reduced the interleukin-4 (IL-4) levels in the lung and kidney and especially the liver and spleen; moreover, CAM significantly reduced the IL-1ß levels in the spleen, liver, and kidney and particularly the small intestine and lung. CAM is predicted to regulate related pathways by acting on many targets, such as albumin, estrogen receptor 1, epidermal growth factor receptor and caspase 3, to treat cancer, inflammation and other diseases. CONCLUSION: We determined that CAM inhibited inflammation. We also predicted the complex multitargeted effects of CAM that involve multiple pathways and the diversity of these effects in the treatment of liver cancer, which provides a basis and direction for further clinical research.
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Medicamentos Herbarios Chinos , Neoplasias Hepáticas , Animales , Ratones , Simulación del Acoplamiento Molecular , Neoplasias Hepáticas/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéuticoRESUMEN
BACKGROUND: Multiple classes of molecular biomarkers have been studied as potential predictors for rectal cancer (RC) response. Carcinoembryonic antigen (CEA) is the most widely used blood-based marker of RC and has proven to be an effective predictive marker. Cancer antigen 19-9 (CA19-9) is another tumor biomarker used for RC diagnosis and postoperative monitoring, as well as monitoring of the therapeutic effect. Using a panel of tumor markers for RC outcome prediction is a practical approach. AIM: To assess the predictive effect of pre-neoadjuvant chemoradiotherapy (NCRT) CEA and CA19-9 levels on the prognosis of stage II/III RC patients. METHODS: CEA and CA19-9 levels were evaluated 1 wk before NCRT. According to the receiver operating characteristic curve analysis, the optimal cut-off point of CEA and CA19-9 levels for the prognosis were 3.55 and 19.01, respectively. The novel serum tumor biomarker (NSTB) scores were as follows: score 0: Pre-NCRT CEA < 3.55 and CA19-9 < 19.01; score 2: Pre-NCRT CEA > 3.55 and CA19-9 > 19.01; score 1: Other situations. Pathological information was recorded according to histopathological reports after the operation. RESULTS: In the univariate analysis, pre-NCRT CEA < 3.55 [P = 0.025 for overall survival (OS), P = 0.019 for disease-free survival (DFS)], pre-NCRT CA19-9 < 19.01 (P = 0.014 for OS, P = 0.009 for DFS), a lower NSTB score (0-1 vs 2, P = 0.009 for OS, P = 0.005 for DFS) could predict a better prognosis. However, in the multivariate analysis, only a lower NSTB score (0-1 vs 2; for OS, HR = 0.485, 95%CI: 0.251-0.940, P = 0.032; for DFS, HR = 0.453, 95%CI: 0.234-0.877, P = 0.019) and higher pathological grade, node and metastasis stage (0-I vs II-III; for OS, HR = 0.363, 95%CI: 0.158-0.837, P = 0.017; for DFS, HR = 0.342, 95%CI: 0.149-0.786, P = 0.012) were independent predictive factors. CONCLUSION: The combination of post-NCRT CEA and CA19-9 was a predictive factor for clinical stage II/III RC patients receiving NCRT, and the combined index had a stronger predictive effect.
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BACKGROUND: Art-based interventions may delay cognitive decline and improve health-related outcomes in older adults with mild cognitive impairment (MCI). OBJECTIVE: To examine the effects of the Creative Expressive Arts-based Storytelling (CrEAS) program compared to active and waitlist controls on neurocognitive and other health-related outcomes in older people with MCI. DESIGN: Three-arm parallel-group, randomised controlled design. PARTICIPANTS: One-hundred and thirty-five adults with MCI (mean age: 70.93 ± 6.91 years). METHODS: Participants were randomly assigned to intervention (CrEAS, n = 45), active control (n = 45) or waitlist control (n = 45) groups. Interventions were applied once per week for 24 weeks. The primary outcome was global cognitive function; secondary outcomes were specific cognition domains (memory, executive function, language and attention) and other health-related outcomes (anxiety, depression and quality of life [QoL]). All variables were measured at baseline (T0), 24-week follow-up (T1) and 48-week follow-up (T2). RESULTS: Participants in the CrEAS group showed significantly higher global cognitive function (adjusted mean difference [MD] = -0.905, 95% confidence interval [CI] -1.748 to -0.062; P = 0.038) and QoL (adjusted MD = -4.150, 95% CI -6.447 to -1.853; P = 0.001) and lower depression symptoms (adjusted MD = 2.902, 95% CI 0.699-5.104; P = 0.011) post-intervention at the 24-week follow-up compared with the active control group. At 48-week follow-up, only the Auditory Verbal Learning Test Immediate recall score was significantly improved compared with the active control group (adjusted MD = -2.941, 95% CI -5.262 to -0.620; P = 0.014). CONCLUSIONS: Older adults with MCI who participated in the CrEAS program improved their neuropsychological outcomes and QoL and reduced their rate of cognitive deterioration.
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Trastornos del Conocimiento , Disfunción Cognitiva , Anciano , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Disfunción Cognitiva/terapia , Función Ejecutiva , Humanos , Calidad de VidaRESUMEN
Expressive arts therapy (EAT) can potentially improve cognition and mental health in patients with dementia. However, limited studies have been conducted for older adults with mild cognitive impairment (MCI). The aim of this study was to examine the effects of EAT in older adults with MCI. A total of 48 participants with MCI were assigned to the EAT intervention (n = 24) or waiting list control (n = 24) group. The former received 60-90 min of EAT twice a week for 6 weeks. The findings showed that the EAT program had a high retention and attendance rate and a high level of general satisfaction. Moreover, the intervention group showed significant improvements in general cognitive function, language function, anxiety, depression, and the psychological and social relationship domains of quality of life. The results provide preliminary evidence for the feasibility and efficacy of EAT intervention in older adults with MCI.
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Disfunción Cognitiva , Calidad de Vida , Anciano , Ansiedad/terapia , Cognición , Disfunción Cognitiva/terapia , Humanos , Proyectos PilotoRESUMEN
BACKGROUND: Penetrating neck injuries require prompt recognition, diagnosis and management of critical airways. This case demonstrates an emergent situation that a "medical negligence" was avoided with the aid of end-tidal carbon dioxide (ETCO2) waveform. CASE SUMMARY: We report a case of malposition of the endotracheal tube into the right hemithoracic cavity for cervical knife trauma, resulting in pneumothorax. Tube placement was not confirmed during emergency airway management, and the patient was directly transferred to the emergency operation room. Assisted by ETCO2 and imaging examinations, the anesthetist timely noticed the absence of ETCO2 waveform and resolved this urgent situation before anesthesia induction. CONCLUSION: This case emphasizes the necessity of ETCO2 waveform and/or X-ray confirmation of endotracheal intubation even in emergent situations.
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INTRODUCTION: Early non-pharmacological interventions can prevent cognitive decline in older adults with mild cognitive impairment (MCI). Creative expression (CrExp) can potentially mitigate cognitive decline and enhance the physical and mental health of older people. However, it is unclear whether activities involving CrExp can improve cognitive function and other health-related outcomes in older adults with MCI. The aim of the present study is to develop a Creative Expressive Arts-based Storytelling (CrEAS) programme that integrates verbal and non-verbal expressive activities and evaluate its effectiveness in improving cognitive function and other outcome indicators so as to explore its possible mechanism from the perspective of neuroimaging. METHODS AND ANALYSIS: This parallel randomised controlled trial with three arms (one intervention and two control arms) will be conducted over a 24-week period. A total of 111 participants will be enrolled and randomised to the CrEAS, recreation and usual activity groups. The CrEAS programme combines visual arts therapy and storytelling (TimeSlips) under the Expressive Therapy Continuum theoretical framework and provides an opportunity for people with MCI to actively engage in activities to improve cognitive function through verbal and nonverbal CrExp. Global cognitive function, specific domains of cognition (memory, executive function, language and attention) and other health-related outcomes (anxiety, depression and quality of life) will be measured at baseline, at the end of the intervention, and at the 24-week follow-up. Structural/functional brain MRI data will be collected at baseline and immediately after the intervention. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Ethics Committee of Fujian Provincial Hospital (K2018-03-061). The study results will be disseminated through peer-reviewed journals and at academic conferences. TRIAL REGISTRATION NUMBER: ChiCTR1900021526.
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Disfunción Cognitiva , Calidad de Vida , Anciano , Anciano de 80 o más Años , Cognición , Disfunción Cognitiva/terapia , Función Ejecutiva , Humanos , MemoriaRESUMEN
Objective: To study the effects of the three methods and three-acupoint technique on DRG gene expression in SNI model rats and to elucidate the molecular mechanism of the three methods and three-acupoint technique on promoting recovery in peripheral nerve injury. Methods: 27 male SD rats were randomly divided into three groups: a Sham group, the SNI group, and the Tuina group. The Tuina group was treated with a tuina manipulation simulator to simulate massage on points, controlling for both quality and quantity. Point-pressing, plucking, and kneading methods were administered quantitatively at Yinmen (BL37), Chengshan (BL57), and Yanglingquan (GB34) points on the affected side once a day, beginning 7 days after modeling. Intervention was applied once a day for 10 days, then 1 day of rest, followed by 10 more days of intervention, totally equaling 20 times of intervention. The effect of the three methods and three-point technique on the recovery of injured rats was evaluated using behavior analysis. RNA sequencing (RNA-Seq) analysis of differentially expressed genes in DRGs of the three groups of rats was also performed. GO and KEGG enrichment was analyzed and verified using real-time PCR. Results: RNA-Seq combined with database information showed that the number of differentially expressed genes in DRG was the largest in the Tuina group compared with the SNI group, totaling 226. GO function is enriched in the positive regulation of cell processes, ion binding, protein binding, neuron, response to pressure, response to metal ions, neuron projection, and other biological processes. GO function is also enriched in the Wnt, IL-17, and MAPK signaling pathways in the KEGG database. PCR results were consistent with those of RNA sequencing, suggesting that the results of transcriptome sequencing were reliable. Conclusion: The three methods and three-acupoint technique can promote the recovery of SNI model rats by altering the gene sequence in DRGs.
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Puntos de Acupuntura , Grupos Diagnósticos Relacionados , Medicina Tradicional China , Traumatismos de los Nervios Periféricos , Tratamiento de Tejidos Blandos , Animales , Masculino , Medicina Tradicional China/métodos , Ratas , Ratas Sprague-Dawley , Nervio Ciático/lesiones , Análisis de Secuencia de ARN , Tratamiento de Tejidos Blandos/métodosRESUMEN
To evaluate the traits and rheological properties of thermosensitive in situ gel of Yihuang Decoction and its common gel for vaginal use, and predict the release behavior of Yihuang Decoction in situ gel in vitro. Poloxamer was used as thermosensitive material to prepare Yihuang Decoction vaginal in situ gel, and Yihuang Decoction common gel was prepared with carbopol. Then the differences of the two gels before and after diluting with vaginal fluid were compared. The rheological parameters of Yihuang Decoction in situ gel and its common gel were determined with Anton Paar MCR102 rheometer. In addition, berberine hydrochloride was selected as an index component to evaluate the in vitro release properties of Yihuang Decoction vaginal thermosensitive in situ gel. Yihuang Decoction vaginal thermosensitive in situ gel was Newtonian fluid under low-temperature conditions, which was yellow and transparent. After reaching the gelling temperature of 24.5 â, it became semi-solid, pseudoplastic fluid. The gelling temperature was predicted to be 37 â, and the phase transition time was 30 s after diluting with simulated vaginal fluid. However, the rheological properties of Yihuang Decoction common gel had no significant changes with temperature. Compared with in situ gel, the color of common gel was darker and more translucent. Besides, its mobility was stronger after diluting with simulated vaginal fluid. The in vitro release study showed that the kinetic behavior of berberine hydrochloride in Yihuang Decoction vaginal thermosensitive in situ gel was matched with the Higuchi equation. Through simulation of vaginal administration, physical properties and dynamic rheological parameters were used to intuitively and scientifically evaluate the two gels. Compared with the common gel, the thermosensitive in situ gel could quickly attached to the vaginal mucosa and release drug, and thus was more suitable for developing vaginal administration of Yihuang Decoction, which also provides references for studying new vaginal preparation of Yihuang Decoction.
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Administración Intravaginal , Medicamentos Herbarios Chinos/química , Geles/química , Femenino , Humanos , Poloxámero , Reología , Temperatura , ViscosidadRESUMEN
The aim of this paper was to explore the potential molecular mechanism of Banxia Xiexin Decoction in the treatment of colon cancer through pharmacology network and molecular docking methods. The chemical constituents and action targets of 7 herbs from Banxia Xiexin Decoction were collected by using TCMSP database,Chinese Pharmacopoeia and literatures consultation. GeneCards database was used to predict the potential targets of colon cancer. GO biological process analysis and KEGG pathway enrichment analysis of the disease and drug intersection targets were carried out through DAVID database. "Component-target-pathway" network and protein-protein interaction(PPI) network were construction by using Cytoscape and STRING database,and then the core components and targets of Banxia Xiexin Decoction in the treatment of colon cancer were selected according to the topological parameters. Finally, Autodock Vina was used to realize the molecular docking of core components and key targets. The prediction results showed that there were 190 active compounds and 324 corresponding targets for Banxia Xiexin Decoction,involving 74 potential targets for colon cancer. Cytoscape topology analysis revealed 11 key targets such as STAT3,TP53,AKT1,TNF,IL6 and SRC, as well as 10 core components such as quercetin,ß-sitosterol,baicalein,berberine,and 6-gingerol.In bioinformatics enrichment analysis, 679 GO terms and 106 KEGG pathways were obtained, mainly involving PI3 K-AKT signaling pathway,TNF signaling pathway and TP53 signaling pathway. The results of molecular docking showed that baicalein,berberine,licochalcone A and 6-gingerol had a high affinity with SRC,STAT3,TNF and IL6. The results suggested that Banxia Xiexin Decoction could play an anti-colon cancer effect by inhibiting cell proliferation, regulating cell cycle, inducing apoptosis and anti-inflammatory function. The study revealed the multi-components,multi-targets and multi-pathways molecular mechanism of Banxia Xiexin Decoction,which could provide scientific basis and research ideas for the clinical application of Banxia Xiexin Decoction and the treatment of colon cancer with compound Chinese medicines.
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Neoplasias del Colon , Medicamentos Herbarios Chinos , Humanos , Simulación del Acoplamiento Molecular , TecnologíaRESUMEN
In this study, a novel automatic analytical methodology using a titanium dioxide (TiO2)-assisted preconcentration/on-site vapor-generation (VG) chip hyphenated with inductively coupled plasma-mass spectrometry (ICP-MS) for online determination of mercuric ions (Hg2+) was developed. Interestingly, the TiO2 nanoparticle (nano-TiO2) coating on the channel surface acted not only as a sorbent for preconcentration but also as a catalyst for photocatalyst-assisted VG. Under optimum operation conditions, the developed method was validated by analyzing the certified reference material (CRM) Seronorm™ Trace Elements Urine L-2 (freeze-dried human urine). Based on the obtained results, the dramatic reduction of "hands-on" manipulation and the elimination of hazardous materials (e.g., sodium borohydride (NaBH4) and stannous chloride (SnCl2)) from the process enabled a simple and ultraclean procedure with an extremely low detection limit of 0.75â¯ngâ¯L-1 for Hg2+ in urine samples. To the best of our knowledge, this is the first study to report the direct exploitation of a nano-TiO2-coated microfluidic device for online sample preconcentration and on-site VG prior to ICP-MS measurement.
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Mercurio/orina , Titanio/química , Humanos , Iones/orina , Espectrometría de Masas/instrumentación , VolatilizaciónRESUMEN
To selectively and sensitively determine the trace inorganic As species, As(III) and As(V), we developed a nanocomposite-coated microfluidic-based photocatalyst-assisted reduction device (PCARD) as a vapor generation (VG) device to couple high-performance liquid chromatography (HPLC) separation and inductively coupled plasma-mass spectrometry (ICPMS) detection. Au nanoparticles were deposited on TiO2 nanoparticles to strengthen the conversion efficiency of the nanocomposite photocatalytic reduction. The sensitivity for As was significantly enhanced by employing the nanocomposite photocatalyst and using prereduction and signal-enhancement reagents. Under the optimal operating conditions, the analytical detection limits (based on 3σ) of the proposed online HPLC/nanocomposite-coated microfluidic-based PCARD/ICPMS system for As(III) and As(V) were 0.23 and 0.34 µg·L-1, respectively. The results were validated using a certified reference material (NIST SRM 1643e) and groundwater sample analysis, indicating the good reliability and applicability of our proposed system for the determination of inorganic As species in natural fresh water.
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Herein, a hyphenated system combining a high-throughput solid-phase extraction (htSPE) microchip with inductively coupled plasma-mass spectrometry (ICP-MS) for rapid determination of trace heavy metals was developed. Rather than performing multiple analyses in parallel for the enhancement of analytical throughput, we improved the processing speed for individual samples by increasing the operation flow rate during SPE procedures. To this end, an innovative device combining a micromixer and a multi-channeled extraction unit was designed. Furthermore, a programmable valve manifold was used to interface the developed microchip and ICP-MS instrumentation in order to fully automate the system, leading to a dramatic reduction in operation time and human error. Under the optimized operation conditions for the established system, detection limits of 1.64-42.54 ng L(-1) for the analyte ions were achieved. Validation procedures demonstrated that the developed method could be satisfactorily applied to the determination of trace heavy metals in natural water. Each analysis could be readily accomplished within just 186 s using the established system. This represents, to the best of our knowledge, an unprecedented speed for the analysis of trace heavy metal ions.
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Laribacter hongkongensis is a food-borne bacterium associated with community-acquired gastroenteritis and diarrhoea. Quinolone resistance was recently reported in bacterial isolates from aquatic products, but the molecular mechanisms for resistance were still unknown. In this study, a total of 157 L. hongkongensis strains were isolated from grass carps (n = 443) and Chinese tiger frogs (n = 171). Twenty-one ciprofloxacin-resistant strains were analysed for mutations in quinolone resistance-determining regions (QRDR), acquired quinolone resistance (AQR) genes and the role of efflux pumps in resistance. All QRDR mutations in gyrA (codons 85 and 89) and parC (codons 83 and 231) were found to be closely associated with ciprofloxacin resistance. The AQR gene aac(6')-Ib-cr was found in 42.9% (9/21) of the resistant strains, but qnrA, qnrB, qnrC, qnrD, qnrS and qepA were not detected. No significant change of MICs to ciprofloxacin was observed in the presence of an efflux pump inhibitor, indicating the role of efflux pump was probably absent. All 21 ciprofloxacin-resistant strains showed different electrophoretic patterns, which suggested they were not genetically related. These data highlight the importance of QRDR mutations and the AQR gene aac(6')-Ib-cr during the development of quinolone resistance in a heterogeneous population of L. hongkongensis.
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Anfibios/microbiología , Antibacterianos/farmacología , Carpas/microbiología , Farmacorresistencia Bacteriana , Neisseriaceae/efectos de los fármacos , Quinolonas/farmacología , Animales , ADN Bacteriano/genética , Genes Bacterianos , Variación Genética , Genotipo , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Mutación , Neisseriaceae/clasificación , Neisseriaceae/genética , Neisseriaceae/aislamiento & purificación , PrevalenciaRESUMEN
A new dibenzofuran, lucidafuran (1), was isolated from the stems of Pourthiaea lucida, together with eight known compounds. The structure of this new compound was determined through NMR and mass-spectrometric analyses. Among the isolated compounds, lucidafuran (1) and aucuparin (3) exhibited potent inhibitory activity against fMLP-induced superoxide (O(*-)(2)) production by human neutrophils with IC(50) values of 18.7+/-4.4 and 17.0+/-6.8 microM, resp.