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1.
Toxicology ; : 153930, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39159712

RESUMEN

Benzophenones (BPs) are widely used as photoinitiators (PIs) or printing inks in food packaging, which may migrate into foods. However, the toxicity information of some BP analogues, such as 4,4'-bis(diethylamino)-benzophenone (DEAB), 4-phenylbenzophenone (4-PBP), 4 (hydroxymethyl)benzophenone (4-HMBP), those are used as PIs is lacking. Developmental toxicity due to long-term and low-dose exposure to PIs is a major health concern. Recently, alternative non-in vivo methods have been proposed to evaluate the concerned chemicals or better understand the modes of action of certain toxicological endpoints. In this study, using in silico methods, we predicted that BP, DEAB, 4-PBP and 4-HMBP might exhibit developmental toxicity. However, we found that only 4, 4'-bis(diethylamino)-benzophenone (DEAB) is strong embryotoxic and disturbs the early differentiation of mouse embryonic stem cells into three germ layers and cardiomyocytes. DEAB treatment also prevented cardiomyocyte differentiation in human induced pluripotent stem cells (hiPSCs) on day 10. However, BP, 4-PBP and 4-HMBP had no similar effects on cardiomyocyte differentiation on day 10. Transcriptomic analysis revealed that treatment with DEAB significantly decreased the mRNA levels of differentiation-related transcription factors SOX17 and FOXA1, in hiPSCs on day 4. Furthermore, DEAB treatment caused tail malformations and yolk sac edema in zebrafish embryos. To conclude, DEAB may be embryotoxic because it disturbs the early differentiation of stem cells. Further studies are warranted to better understand the health effects of DEAB exposure.

2.
ACS Appl Mater Interfaces ; 16(32): 41734-41742, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39093613

RESUMEN

The development of sustainable and effective electrochemical nitrogen fixation catalysts is crucial for the mitigation of the terrible energy consumption resulting from the Haber-Bosch process. Molybdenum disulfide (MoS2) exhibits promise toward nitrogen reduction reaction (NRR) on account of its similar structure to natural nitrogenases MoFe-co but still undergoes serious challenges with unsatisfactory catalytic performance resulted from limited active sites, conductivity, and selectivity. In this work, Fe/Co/B codoped MoS2 ultrathin nanosheets are synthesized and verified as excellent NRR catalysts with high activity, selectivity, and durability. The FeCoB-MoS2 demonstrates a high ammonia yield of 36.99 µg h-1 mgcat-1 at -0.15 V vs RHE and Faraday efficiency (FE) of 30.65% at -0.10 V vs RHE in 0.1 M HCl. The experimental results and the density functional theory (DFT) calculations emphasize that codoping of Fe, Co, and B into MoS2 synergistically enhances its conductivity and optimizes the electronic structure of the catalyst, which significantly improves the electrocatalytic ammonia synthesis performance. This work broadens the potential and enlightens the strategy for designing efficient electrocatalysts in the NRR field.

3.
Microb Cell Fact ; 23(1): 225, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39123211

RESUMEN

BACKGROUND: To effectively introduce plasmids into Bacillus species and conduct genetic manipulations in Bacillus chassis strains, it is essential to optimize transformation methods. These methods aim to extend the period of competence and enhance the permeability of the cell membrane to facilitate the entry of exogenous DNA. Although various strategies have been explored, few studies have delved into identifying metabolites and pathways associated with enhanced competence. Additionally, derivative Bacillus strains with non-functional restriction-modification systems have demonstrated superior efficiency in transforming exogenous DNA, lacking more explorations in the regulation conducted by the restriction-modification system to transformation process. RESULTS: Transcriptomic comparisons were performed to discover the competence forming mechanism and the regulation pathway conducted by the BsuMI methylation modification group in Bacillus. subtilis 168 under the Spizizen transformation condition, which were speculated to be the preferential selection of carbon sources by the cells and the preference for specific metabolic pathway when utilizing the carbon source. The cells were found to utilize the glycolysis pathway to exploit environmental glucose while reducing the demand for other phosphorylated precursors in this pathway. The weakening of these ATP-substrate competitive metabolic pathways allowed more ATP substrates to be distributed into the auto-phosphorylation of the signal transduction factor ComP during competence formation, thereby increasing the expression level of the key regulatory protein ComK. The expression of ComK upregulated the expression of the negative regulator SacX of starch and sucrose in host cells, reinforcing the preference for glucose as the primary carbon source. The methylation modification group of the primary protein BsuMI in the restriction-modification system was associated with the functional modification of key enzymes in the oxidative phosphorylation pathway. The absence of the BsuMI methylation modification group resulted in a decrease in the expression of subunits of cytochrome oxidase, leading to a weakening of the oxidative phosphorylation pathway, which promoted the glycolytic rate of cells and subsequently improved the distribution of ATP molecules into competence formation. A genetic transformation platform for wild-type Bacillus strains was successfully established based on the constructed strain B. subtilis 168-R-M- without its native restriction-modification system. With this platform, high plasmids transformation efficiencies were achieved with a remarkable 63-fold improvement compared to the control group and an increased universality in Bacillus species was also obtained. CONCLUSIONS: The enhanced competence formation mechanism and the regulation pathway conducted by the functional protein BsuMI of the restriction-modification system were concluded, providing a reference for further investigation. An effective transformation platform was established to overcome the obstacles in DNA transformations in wild-type Bacillus strains.


Asunto(s)
Bacillus subtilis , Proteínas Bacterianas , Transformación Bacteriana , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Plásmidos/genética , Plásmidos/metabolismo , Competencia de la Transformación por ADN
4.
BMC Med Genomics ; 17(1): 216, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160503

RESUMEN

BACKGROUND: There is growing evidence for a relationship between gut microbiota and hepatic encephalopathy (HE). However, the causal nature of the relationship between gut microbiota and HE has not been thoroughly investigated. METHOD: This study utilized the large-scale genome-wide association studies (GWAS) summary statistics to evaluate the causal association between gut microbiota and HE risk. Specifically, two-sample Mendelian randomization (MR) approach was used to identify the causal microbial taxa for HE. The inverse variance weighted (IVW) method was used as the primary MR analysis. Sensitive analyses were performed to validate the robustness of the results. RESULTS: The IVW method revealed that the genus Bifidobacterium (OR = 0.363, 95% CI: 0.139-0.943, P = 0.037), the family Bifidobacteriaceae (OR = 0.359, 95% CI: 0.133-0.950, P = 0.039), and the order Bifidobacteriales (OR = 0.359, 95% CI: 0.133-0.950, P = 0.039) were negatively associated with HE. However, no causal relationship was observed among them after the Bonferroni correction test. Neither heterogeneity nor horizontal pleiotropy was found in the sensitivity analysis. CONCLUSION: Our MR study demonstrated a potential causal association between Bifidobacterium, Bifidobacteriaceae, and Bifidobacteriales and HE. This finding may provide new therapeutic targets for patients at risk of HE in the future.


Asunto(s)
Microbioma Gastrointestinal , Estudio de Asociación del Genoma Completo , Encefalopatía Hepática , Análisis de la Aleatorización Mendeliana , Humanos , Encefalopatía Hepática/genética , Encefalopatía Hepática/microbiología , Bifidobacterium/genética
5.
World J Gastrointest Surg ; 16(6): 1948-1952, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983360

RESUMEN

BACKGROUND: The management of polyps involving the appendiceal orifice (AO) presents notable challenges. Endoscopic resection is frequently hindered by operational complexities, a heightened risk of incomplete removal, and an elevated risk of procedural complications, including appendicitis. Conversely, surgical resection may entail unnecessary excision of intestinal segments, leading to potential morbidity. CASE SUMMARY: Here, we reported two patients who presented with polyps deeply situated within the AO, with indistinct boundaries making it challenging to ensure completeness using traditional endoscopic resection. To overcome these challenges, we employed combined endo-laparoscopic surgery (CELS), achieving curative resection without postoperative complications. CONCLUSION: The application of CELS in managing polyps involving the AO is emerging as a safe and effective treatment modality.

6.
Nurs Open ; 11(7): e2234, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39032162

RESUMEN

AIMS AND OBJECTIVES: This study aimed to investigate the current status of the core competencies and self-directed learning ability of diabetes specialist nurses and to explore the relationship between these core competencies and their self-directed learning ability. DESIGN: A cross-sectional survey design was used. METHODS: This cross-sectional study was conducted via a web-based questionnaire platform in China from January 14 to April 24, 2023. The survey included a general information questionnaire, a diabetes specialist nurses' core competencies self-assessment scale, and a nursing staff's self-directed learning ability evaluation scale. The data was collected online. Descriptive, correlation and multiple linear regression analyses were conducted using SPSS 26.0 software. RESULTS: 118 diabetes specialist nurses from 11 cities participated in this study. A positive correlation was observed between the core competencies of diabetes specialist nurses and their self-directed learning ability. The characteristics affecting the core competencies of diabetes specialist nurses included age, participation in external learning and communication and self-directed learning. CONCLUSIONS: The training of diabetes specialist nurses can focus on core competencies, and the ability to self-direct learning can be used as an entry point to customize feasible theoretical and practical courses. The training system can further improve diabetes specialist nurses' core competencies and self-directed learning abilities. RELEVANCE TO CLINICAL PRACTICE: A reference can be established that nursing managers and nursing educators can use to develop training programs for specialist nurses by validating the link between their core competencies and self-directed learning skills. PATIENT OR PUBLIC CONTRIBUTION: Participants were involved solely in the data collection process. No participant contributions were required for the study's design, outcome measurement or implementation.


Asunto(s)
Competencia Clínica , Diabetes Mellitus , Humanos , Estudios Transversales , Adulto , Masculino , Femenino , Encuestas y Cuestionarios , Competencia Clínica/normas , China , Diabetes Mellitus/enfermería , Diabetes Mellitus/psicología , Persona de Mediana Edad , Autoaprendizaje como Asunto
8.
Ann Acad Med Singap ; 53(3): 170-186, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38920244

RESUMEN

Introduction: Tuberculosis (TB) remains endemic in Singapore. Singapore's clinical practice guidelines for the management of tuberculosis were first published in 2016. Since then, there have been major new advances in the clinical management of TB, ranging from diagnostics to new drugs and treatment regimens. The National TB Programme convened a multidisciplinary panel to update guidelines for the clinical management of drug-susceptible TB infection and disease in Singapore, contextualising current evidence for local practice. Method: Following the ADAPTE framework, the panel systematically reviewed, scored and synthesised English-language national and international TB clinical guidelines published from 2016, adapting recommendations for a prioritised list of clinical decisions. For questions related to more recent advances, an additional primary literature review was conducted via a targeted search approach. A 2-round modified Delphi process was implemented to achieve consensus for each recommendation, with a final round of edits after consultation with external stakeholders. Results: Recommendations for 25 clinical questions spanning screening, diagnosis, selection of drug regimen, monitoring and follow-up of TB infection and disease were formulated. The availability of results from recent clinical trials led to the inclusion of shorter treatment regimens for TB infection and disease, as well as consensus positions on the role of newer technologies, such as computer-aided detection-artificial intelligence products for radiological screening of TB disease, next-generation sequencing for drug-susceptibility testing, and video observation of treatment. Conclusion: The panel updated recommendations on the management of drug-susceptible TB infection and disease in Singapore.


Asunto(s)
Antituberculosos , Técnica Delphi , Tuberculosis Pulmonar , Tuberculosis , Humanos , Singapur , Antituberculosos/uso terapéutico , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/diagnóstico , Consenso
9.
Neurochem Int ; 178: 105786, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38843952

RESUMEN

Our previous study has identified that glutamate in the red nucleus (RN) facilitates the development of neuropathic pain through metabotropic glutamate receptors (mGluR). Here, we further explored the actions and possible molecular mechanisms of red nucleus mGluR Ⅰ (mGluR1 and mGluR5) in the development of neuropathic pain induced by spared nerve injury (SNI). Our data indicated that both mGluR1 and mGluR5 were constitutively expressed in the RN of normal rats. Two weeks after SNI, the expressions of mGluR1 and mGluR5 were significantly boosted in the RN contralateral to the nerve injury. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN contralateral to the nerve injury at 2 weeks post-SNI significantly ameliorated SNI-induced neuropathic pain. However, unilateral administration of mGluRⅠ agonist DHPG to the RN of normal rats provoked a significant mechanical allodynia, this effect could be blocked by LY367385 or MTEP. Further studies indicated that the expressions of TNF-α and IL-1ß in the RN were also elevated at 2 weeks post-SNI. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN at 2 weeks post-SNI significantly inhibited the elevations of TNF-α and IL-1ß. However, administration of mGluR Ⅰ agonist DHPG to the RN of normal rats significantly enhanced the expressions of TNF-α and IL-1ß, these effects were blocked by LY367385 or MTEP. These results suggest that activation of red nucleus mGluR1 and mGluR5 facilitate the development of neuropathic pain by stimulating the expressions of TNF-α and IL-1ß. mGluR Ⅰ maybe potential targets for drug development and clinical treatment of neuropathic pain.


Asunto(s)
Interleucina-1beta , Neuralgia , Ratas Sprague-Dawley , Receptor del Glutamato Metabotropico 5 , Receptores de Glutamato Metabotrópico , Núcleo Rojo , Factor de Necrosis Tumoral alfa , Animales , Neuralgia/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Receptores de Glutamato Metabotrópico/agonistas , Masculino , Receptor del Glutamato Metabotropico 5/metabolismo , Receptor del Glutamato Metabotropico 5/antagonistas & inhibidores , Interleucina-1beta/metabolismo , Interleucina-1beta/biosíntesis , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Ratas , Núcleo Rojo/metabolismo , Núcleo Rojo/efectos de los fármacos
10.
World J Gastrointest Surg ; 16(5): 1259-1270, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38817289

RESUMEN

BACKGROUND: Intestinal flora disorder (IFD) poses a significant challenge after laparoscopic colonic surgery, and no standard criteria exists for its diagnosis and treatment. AIM: To analyze the clinical features and risk factors of IFD. METHODS: Patients with colon cancer receiving laparoscopic surgery were included using propensity-score-matching (PSM) methods. Based on the occurrence of IFD, patients were categorized into IFD and non-IFD groups. The clinical characteristics and treatment approaches for patients with IFD were analyzed. Multivariate regression analysis was performed to identify the risk factors of IFD. RESULTS: The IFD incidence after laparoscopic surgery was 9.0% (97 of 1073 patients). After PSM, 97 and 194 patients were identified in the IFD and non-IFD groups, respectively. The most common symptoms of IFD were diarrhea and abdominal, typically occurring on post-operative days 3 and 4. All patients were managed conservatively, including modulation of the intestinal flora (90.7%), oral/intravenous application of vancomycin (74.2%), and insertion of a gastric/ileus tube for decompression (23.7%). Multivariate regression analysis identified that pre-operative intestinal obstruction [odds ratio (OR) = 2.79, 95%CI: 1.04-7.47, P = 0.041] and post-operative antibiotics (OR = 8.57, 95%CI: 3.31-23.49, P < 0.001) were independent risk factors for IFD, whereas pre-operative parenteral nutrition (OR = 0.12, 95%CI: 0.06-0.26, P < 0.001) emerged as a protective factor. CONCLUSION: A stepwise approach of probiotics, vancomycin, and decompression could be an alternative treatment for IFD. Special attention is warranted post-operatively for patients with pre-operative obstruction or early use of antibiotics.

11.
Genes Genomics ; 46(7): 851-870, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38809491

RESUMEN

BACKGROUND: The Bradybaenidae snail Karaftohelix adamsi is endemic to Korea, with the species tracked from Island Ulleung in North Gyeongsang Province of South Korea. K. adamsi has been classified under the Endangered Wildlife Class II species of Korea and poses a severe risk of extinction following habitat disturbances. With no available information at the DNA (genome) or mRNA (transcriptome) level for the species, conservation by utilizing informed molecular resources seems difficult. OBJECTIVE: In this study, we used the Illumina short-read sequencing and Trinity de novo assembly to draft the reference transcriptome of K. adamsi. RESULTS: After assembly, 13,753 unigenes were obtained of which 10,511 were annotated to public databases (a maximum of 10,165 unigenes found homologs in PANM DB). A total of 6,351, 3,535, 358, and 3,407 unigenes were ascribed to the functional categories under KOG, GO, KEGG, and IPS, respectively. The transcripts such as the HSP 70, aquaporin, TLR, and MAPK, among others, were screened as putative functional resources for adaptation. DNA transposons were found to be thickly populated in comparison to retrotransposons in the assembled unigenes. Further, 2,164 SSRs were screened with the promiscuous presence of dinucleotide repeats such as AC/GT and AG/CT. CONCLUSION: The transcriptome-guided discovery of molecular resources in K. adamsi will not only serve as a basis for functional genomics studies but also provide sustainable tools to be utilized for the protection of the species in the wild. Moreover, the development of polymorphic SSRs is valuable for the identification of species from newer habitats and cross-species genotyping.


Asunto(s)
Especies en Peligro de Extinción , Repeticiones de Microsatélite , Caracoles , Transcriptoma , Animales , Repeticiones de Microsatélite/genética , Caracoles/genética , Transcriptoma/genética , República de Corea , Anotación de Secuencia Molecular , Aptitud Genética
13.
J Diabetes ; 16(4): e13540, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38599845

RESUMEN

OBJECTIVE: Mitochondria-associated membranes (MAMs) serve pivotal functions in hepatic insulin resistance (IR). Our aim was to explore the potential role of MAMs in mitigating hepatic IR through exercise and to compare the effects of different intensities of exercise on hepatic MAMs formation in high-fat diet (HFD) mice. METHODS: Male C57BL/6J mice were fed an HFD and randomly assigned to undergo supervised high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT). IR was evaluated using the serum triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-C), glucose tolerance test (GTT), and insulin tolerance test (ITT). Hepatic steatosis was observed using hematoxylin-eosin (H&E) and oil red O staining. The phosphatidylinositol 3-kinase/protein kinase B/glycogen synthase kinase 3 beta (PI3K-AKT-GSK3ß) signaling pathway was assessed to determine hepatic IR. MAMs were evaluated through immunofluorescence (colocalization of voltage-dependent anion-selective channel 1 [VDAC1] and inositol 1,4,5-triphosphate receptor [IP3R]). RESULTS: After 8 weeks on an HFD, there was notable inhibition of the hepatic PI3K/Akt/GSK3ß signaling pathway, accompanied by a marked reduction in hepatic IP3R-VDAC1 colocalization levels. Both 8-week HIIT and MICT significantly enhanced the hepatic PI3K/Akt/GSK3ß signaling and colocalization levels of IP3R-VDAC1 in HFD mice, with MICT exhibiting a stronger effect on hepatic MAMs formation. Furthermore, the colocalization of hepatic IP3R-VDAC1 positively correlated with the expression levels of phosphorylation of protein kinase B (p-AKT) and phosphorylation of glycogen synthase kinase 3 beta (p-GSK3ß), while displaying a negative correlation with serum triglyceride/high-density lipoprotein cholesterol levels. CONCLUSION: The reduction in hepatic MAMs formation induced by HFD correlates with the development of hepatic IR. Both HIIT and MICT effectively bolster hepatic MAMs formation in HFD mice, with MICT demonstrating superior efficacy. Thus, MAMs might wield a pivotal role in exercise-induced alleviation of hepatic IR.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Resistencia a la Insulina , Masculino , Ratones , Animales , Resistencia a la Insulina/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Fosfatidilinositol 3-Quinasas , Dieta Alta en Grasa/efectos adversos , Membranas Asociadas a Mitocondrias , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Triglicéridos , Lipoproteínas HDL , Colesterol
14.
Food Sci Nutr ; 12(4): 2917-2931, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38628198

RESUMEN

Sinapic acid (SA) is renowned for its many pharmacological activities as a polyphenolic compound. The cause of polycystic ovary syndrome (PCOS), a commonly encountered array of metabolic and hormonal abnormalities in females, has yet to be determined. The present experiment was performed to evaluate the antifibrotic properties of SA in rats with letrozole-induced PCOS-related ovarian fibrosis. SA treatment successfully mitigated the changes induced by letrozole in body weight (BW) (p < .01) and relative ovary weight (p < .05). Histological observation revealed that SA reduced the number of atretic and cystic follicles (AFs) and (CFs) (p < .01), as well as ovarian fibrosis, in PCOS rats. Additionally, SA treatment impacted the serum levels of sex hormones in PCOS rats. Luteinizing hormone (LH) and testosterone (T) levels were decreased (p < .01, p < .05), and follicle-stimulating hormone (FSH) levels were increased (p < .05). SA administration also decreased triglyceride (TG) (p < .01) and total cholesterol (TC) levels (p < .05) and increased high-density lipoprotein cholesterol (HDL-C) levels (p < .01), thereby alleviating letrozole-induced metabolic dysfunction in PCOS rats. Furthermore, SA treatment targeted insulin resistance (IR) and increased the messenger RNA (mRNA) levels of antioxidant enzymes in the ovaries of PCOS rats. Finally, SA treatment enhanced the activity of peroxisome proliferator-activated receptor-γ (PPAR-γ), reduced the activation of transforming growth factor-ß1 (TGF-ß1)/Smads, and decreased collagen I, α-smooth muscle actin (α-SMA), and connective tissue growth factor (CTGF) levels in the ovaries of PCOS rats. These observations suggest that SA significantly ameliorates metabolic dysfunction and oxidative stress and ultimately reduces ovarian fibrosis in rats with letrozole-induced PCOS.

15.
Adv Sci (Weinh) ; 11(28): e2401780, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38666391

RESUMEN

Creating specific noble metal/metal-organic framework (MOF) heterojunction nanostructures represents an effective strategy to promote water electrolysis but remains rather challenging. Herein, a heterojunction electrocatalyst is developed by growing Ir nanoparticles on ultrathin NiFe-MOF nanosheets supported by nickel foam (NF) via a readily accessible solvothermal approach and subsequent redox strategy. Because of the electronic interactions between Ir nanoparticles and NiFe-MOF nanosheets, the optimized Ir@NiFe-MOF/NF catalyst exhibits exceptional bifunctional performance for the hydrogen evolution reaction (HER) (η10 = 15 mV, η denotes the overpotential) and oxygen evolution reaction (OER) (η10 = 213 mV) in 1.0 m KOH solution, superior to commercial and recently reported electrocatalysts. Density functional theory calculations are used to further investigate the electronic interactions between Ir nanoparticles and NiFe-MOF nanosheets, shedding light on the mechanisms behind the enhanced HER and OER performance. This work details a promising approach for the design and development of efficient electrocatalysts for overall water splitting.

16.
Langmuir ; 40(13): 6786-6805, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38503426

RESUMEN

Traditional heterogeneous catalysts are affected in the catalytic hydrogenation of PS by the scale effect, viscosity effect, adhesion effect, and conformational effect, resulting in poor activity and stability. Monolithic Pd-CNTs@FN catalysts could eliminate or weaken the impact of these negative effects. We grew nitrogen-doped carbon nanotubes (NCNTs) on monolithic-foamed nickel (FN) and investigate their growth mechanism. Meanwhile, the feasibility of using the NCNTs@FN carrier for PS hydrogenation reaction was also verified. The growth of NCNTs on FN can be divided into 3 stages: initial growth stage, stable growth stage, and supersaturation stage. Finally, a three-layer structure of NCNT layer, dense carbon layer, and FN skeleton is formed. Two types of structures, nickel-doped carbon nanotubes (NiCNTs) and C-Ni alloy, are formed by combining C and Ni, while four nitrogen-doped structures, NPD, NPR, NG, and NO, are formed by C and N. The prepared carrier exhibited an extremely outstanding specific surface area (2.829 × 106 cm2/g) and strength (no NCNTs falling off after 24 h 500 rpm agitation), as well as high catalytic activity for PS hydrogenation after loaded with Pd (2.13 ± 0.95 nm), with a TOF of up to 27.6 gPS/(gPd•h). After 8 repetitions of the catalyst, there was no significant decrease in activity. This proves the excellent performance of Pd-NCNTs@FN in polymer hydrogenation reactions, laying a solid foundation for further research on the mechanism of NCNTs promoting PS hydrogenation and regulating the growth of NCNTs.

18.
Opt Lett ; 49(3): 415-417, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300033

RESUMEN

We present a corrigendum to our Letter [Opt. Lett.48, 5699 (2023)10.1364/OL.505761]. In section 3 of the original supplementary material, the absolute value is incorrectly taken in resolving the Kubo formula for describing the conductivity of graphene. Because this is a mistake with the conductivity of graphene, the coupling of the original structure is broken when the correct result is inserted into the code of the transfer matrix. So, the structure of the arithmetic logic unit (ALU), characteristic frequency point, and phase control have been modified accordingly. However, the ultimate function and the conclusion of this work remain unchanged.

19.
Front Med (Lausanne) ; 11: 1346590, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38362537

RESUMEN

The formation of an internal fistula between the biliary system and the gastrointestinal tract is a rare condition with various etiologies, predominantly associated with recurrent chronic inflammation of the biliary system and tumors. Patients with this condition may lack specific clinical manifestations, presenting with symptoms such as abdominal pain, fever, jaundice, or may show no clinical signs at all. Common types of internal fistulas include cholecystoduodenal fistula, cholecystocolonic fistula, and choledochoduodenal fistula. Among these, the right hepaticoduodenal fistula is extremely rare and seldom reported in clinical literature. We herein report a case of right hepaticoduodenal fistula and analyze its mechanism, treatment principles, and preventive measures through a literature review.

20.
Phys Chem Chem Phys ; 26(5): 4447-4454, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38240154

RESUMEN

A one-dimensional optical biosensing metastructure (OBM) with graphene layers is presented in this paper. It is realized by coherent perfect absorption (CPA) and operates in the transverse electric mode. It shows a strong linear fitting relationship between the refractive index (RI) of the analysis layer and the frequency corresponding to the absorption peak, and the R-square is up to 1. Additionally, based on the principle of CPA, the OBM can realize the function of multiple cancer cell detection by adjusting the detection range by controlling the phase difference of coherent electromagnetic waves. Its detection ranges are 1.34-1.355 and 1.658-1.662. Thanks to its high-quality factor, great figure of merit, and low detection limit, whose best values are, respectively, 6.9 × 104, 1.2 × 104 RIU-1, and 3.6 × 10-6 RIU, the detection of weak changes in the RI of a cancer cell is possible. Additionally, its sensitivity can reach 26.57 THz RIU-1. This OBM based on CPA has major implications for advancing the study and investigation into the application of CPA. It also provides a simple and efficient approach to distinguish cancer cells and may be widely used in the biomedical field.


Asunto(s)
Grafito , Neoplasias , Humanos , Electricidad , Neoplasias/diagnóstico
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