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1.
Proc Natl Acad Sci U S A ; 121(4): e2314396121, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38236736

RESUMEN

In our quest to leverage the capabilities of the emerging single-atom catalysts (SACs) for wastewater purification, we confronted fundamental challenges related to electron scarcity and instability. Through meticulous theoretical calculations, we identified optimal placements for nitrogen vacancies (Nv) and iron (Fe) single-atom sites, uncovering a dual-site approach that significantly amplified visible-light absorption and charge transfer dynamics. Informed by these computational insights, we cleverly integrated Nv into the catalyst design to boost electron density around iron atoms, yielding a potent and flexible photoactivator for benign peracetic acid. This exceptional catalyst exhibited remarkable stability and effectively degraded various organic contaminants over 20 cycles with self-cleaning properties. Specifically, the Nv sites captured electrons, enabling their swift transfer to adjacent Fe sites under visible light irradiation. This mechanism accelerated the reduction of the formed "peracetic acid-catalyst" intermediate. Theoretical calculations were used to elucidate the synergistic interplay of dual mechanisms, illuminating increased adsorption and activation of reactive molecules. Furthermore, electron reduction pathways on the conduction band were elaborately explored, unveiling the production of reactive species that enhanced photocatalytic processes. A six-flux model and associated parameters were also applied to precisely optimize the photocatalytic process, providing invaluable insights for future photocatalyst design. Overall, this study offers a molecule-level insight into the rational design of robust SACs in a photo-Fenton-like system, with promising implications for wastewater treatment and other high-value applications.

2.
J Antimicrob Chemother ; 79(3): 678-682, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38319867

RESUMEN

OBJECTIVES: To characterize the genetic environments of ESBL gene blaVEB-1 in mcr-positive Aeromonas strains from raw meat in China. METHODS: Whole genomes of Aeromonas strains were sequenced using the Illumina or Nanopore platforms. Genetic environments of blaVEB-1 were analysed using the BLAST program. RESULTS: The blaVEB-1 gene was detected in five Aeromonas strains carrying the mcr-7-like gene. WGS revealed that all blaVEB-1 genes were located on Aeromonas chromosome, and were carried by two novel different genomic islands named Aeromonas veronii genomic islands AveGI1 and AveGI2, as well as one transposon named Tn7690. AveGI1 is a new member of the Salmonella genomic island 1 family, incorporated into the 3'-end of mnmE (trmE). AveGI2 is a novel genomic island that has a size of 23 180 bp and is incorporated into the 3'-end of syd. The MDR regions of AveGI1 and AveGI2 are two different class 1 integrons containing 10 and five resistance genes, respectively. Tn7690 is a Tn1722 derivative containing In4-type integron and Tn5393, which harbours 10 resistance genes and integrates into different positions on the chromosomes of three strains with the capacity for mobility. CONCLUSIONS: We report chromosomally located novel MDR genomic islands and transposon that carry blaVEB-1 in mcr-positive Aeromonas strains. These genetic elements may mediate the spread of blaVEB-1 in Aeromonas, and may also evolve by capturing new antimicrobial resistance genes or other mobile genetic elements.


Asunto(s)
Aeromonas , Aeromonas/genética , Islas Genómicas , China , Integrones , Carne
3.
Artículo en Inglés | MEDLINE | ID: mdl-39019317

RESUMEN

OBJECTIVE: Recombinant human hepatocyte growth factor (HGF) plasmids are novel alternatives to salvage limbs in patients with chronic limb threatening ischaemia (CLTI). A systematic review and meta-analysis of data was conducted to assess the therapeutic efficacy of HGF plasmids in patients with CLTI. DATA SOURCES: Randomised controlled studies evaluating HGF plasmid efficacy in patients with CLTI were identified using MEDLINE, Embase, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov databases. REVIEW METHODS: Meta-analyses of the reported relative risk (RR) or mean difference (MD) were conducted. Subgroup analyses were performed to determine the efficacy of HGF plasmids in cohorts excluding Buerger's disease. Certainty of evidence for each outcome was assessed. RESULTS: Seven studies (n = 655 participants) were included. Based on low certainty evidence, patients treated with HGF had a significantly higher complete ulcer healing rate (RR 1.99, 95% confidence interval [CI] 1.30 - 3.04; p = .002) than patients treated with placebo. HGF treatment was associated with reduced visual analogue scale (VAS) scores of pain severity (MD -1.56, 95% CI -2.12 - -1.00; p < .001) vs. placebo in patients with CLTI assessed at three month follow up (low certainty evidence); no significant differences were observed in major amputation (RR 0.91, 95% CI 0.48 - 1.73; p = .77) (low certainty evidence) or all cause mortality rate (RR 0.93, 95% CI 0.38 - 2.27; p = .87) (low certainty evidence) between patients treated with HGF and placebo. Low certainty evidence suggested no significant differences in change in ankle brachial index at six months (MD 0.00, 95% CI -0.09 - 0.09; p = 1.0) between patients treated with HGF and placebo. The complete ulcer healing rate and improved three month VAS scores of pain severity benefits persisted in subgroup analyses (low certainty evidence). CONCLUSION: Low certainty evidence suggested that HGF treatment is associated with an increased complete ulcer healing rate and reduced ischaemic pain in patients with CLTI.

4.
Environ Sci Technol ; 58(27): 12155-12166, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38934735

RESUMEN

The rising in situ chemical oxidation (ISCO) technologies based on polymerization reactions have advanced the removal of emerging contaminants in the aquatic environment. However, despite their promise, uncertainties persist regarding their effectiveness in eliminating structurally complex contaminants, such as sulfonamide antibiotics (SAs). This study elucidated that oligomerization, rather than mineralization, predominantly governs the removal of SAs in the carbon materials/periodate system. The amine groups in SAs played a crucial role in forming organic radicals and subsequent coupling reactions due to their high f- index and low bond orders. Moreover, the study highlighted the robust adhesion of oligomers to the catalyst surface, facilitated by enhanced van der Waals forces and hydrophobic interactions. Importantly, plant and animal toxicity assessments confirmed the nontoxic nature of oligomers deposited on the carbon material surface, affirming the efficacy of carbon material-based ISCO in treating contaminated surface water and groundwater. Additionally, a novel classification approach, Δlog k, was proposed to differentiate SAs based on their kinetic control steps, providing deeper insights into the quantitative structure-activity relationship (QSAR) and facilitating the selection of optimal descriptors during the oligomerization processes. Overall, these insights significantly enhance our understanding of SAs removal via oligomerization and demonstrate the superiority of C-ISCO based on polymerization in water decontamination.


Asunto(s)
Antibacterianos , Carbono , Sulfonamidas , Antibacterianos/química , Carbono/química , Sulfonamidas/química , Contaminantes Químicos del Agua/química , Purificación del Agua
5.
Phys Chem Chem Phys ; 26(23): 16664-16673, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38808589

RESUMEN

For the conversion of fructose/methylglucoside (MG) into both methyl formate (MF) and methyl levulinate (MLev), the C-source of formate [HCOO]- remains unclear at the molecular level. Herein, reaction mechanisms catalyzed by [CH3OH2]+ in a methanol solution were theoretically investigated at the PBE0/6-311++G(d,p) level. For the conversion of fructose into MF and MLev, the formate [HCOO]- comes from the C1-atom of fructose, in which the rate-determining step lies in the reaction of 5-hydroxymethylfurfural (HMF) with CH3OH to yield MF and MLev. The reaction of fructose with CH3OH kinetically tends to generate HMF intermediates rather than yield (MF + MLev). When MG is dissolved in a methanol solution, its O2, O3, and O4 atoms are closer to the first layer of the solvent than O1, O5, and O6 atoms. For the dehydration of MG with methanol into MF and MLev, the formate [HCOO]- stems from the dominant C1- and secondary C3-atoms of MG. Kinetically, MG is ready to yield (MF + MLev), whereas fructose can induce the reaction to remain at the HMF intermediate, inhibiting the further conversion of HMF with CH3OH into MF and MLev. If MG isomerizes into fructose, the reaction will be more preferable for yielding HMF rather than (MF + MLev).

6.
Phys Chem Chem Phys ; 26(20): 14613-14623, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38739028

RESUMEN

A Ru-containing complex shows good catalytic performance toward the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) with the assistance of organic base ligands (OBLs) and CO2. Herein, we report the competitive mechanisms for the hydrogenation of LA to GVL, 4-oxopentanal (OT), and 2-methyltetrahydro-2,5-furandiol (MFD) with HCOOH or H2 as the H source catalyzed by RuCl3 in aqueous solution at the M06/def2-TZVP, 6-311++G(d,p) theoretical level. Kinetically, the hydrodehydration of LA to GVL is predominant, with OT and MFD as side products. With HCOOH as the H source, initially, the OBL (triethylamine, pyridine, or triphenylphosphine) is responsible for capturing H+ from HCOOH, leading to HCOO- and [HL]+. Next, the Ru3+ site is in charge of sieving H- from HCOO-, yielding [RuH]2+ hydride and CO2. Alternatively, with H2 as the H source, the OBL stimulates the heterolysis of H-H bond with the aid of Ru3+ active species, producing [RuH]2+ and [HL]+. Toward the [RuH]2+ formation, H2 as the H source exhibits higher activity than HCOOH as the H source in the presence of an OBL. Thereafter, H- in [RuH]2+ gets transferred to the unsaturated C site of ketone carbonyl in LA. Afterwards, the Ru3+ active species is capable of cleaving the C-OH bond in 4-hydroxyvaleric acid, yielding [RuOH]2+ hydroxide and GVL. Subsequently, CO2 promotes Ru-OH bond cleavage in [RuOH]2+, forming HCO3- and regenerating the Ru3+-active species owing to its Lewis acidity. Lastly, between the resultant HCO3- and [HL]+, a neutralization reaction occurs, generating H2O, CO2, and OBLs. Thus, the present study provides insights into the promotive roles of additives such as CO2 and OBLs in Ru-catalyzed hydrogenation.

7.
J Biochem Mol Toxicol ; 38(1): e23628, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38229317

RESUMEN

This study aimed to explore the mechanism by which postembryonic renal ADAMTS18 methylation influences obstructive renal fibrosis in rats. After exposure to transforming growth factor (TGF)-ß1 during the embryonic period, analysis of postembryonic renal ADAMTS18 methylation and expression levels was conducted. Histological analysis was performed to assess embryonic kidney lesions and damage. Western blot analysis was used to determine the expression of renal fibrosis markers. Rats with ureteral obstruction and a healthy control group were selected. The methylation levels of ADAMTS18 in the different groups were analyzed. Western blot analysis and immunohistochemistry were performed to analyze the expression of renal fibrosis markers, and kidney-related indicators were measured. Treatment with TGF-ß1 resulted in abnormal development of the postembryonic kidney, which was characterized by rough kidney surfaces with mild depressions and irregularities on the outer surface. TGF-ß1 treatment significantly promoted ADAMTS18 methylation and activated the protein kinase B (AKT)/Notch pathway. Ureteral obstruction was induced to establish a renal hydronephrosis model, which led to renal fibrotic injury in newborn rats. Overexpression of the ADAMTS18 gene alleviated renal fibrosis. The western blot results showed that compared to that in the control group, the expression of renal fibrosis markers was significantly decreased after ADAMTS18 overexpression, and there was a thicker renal parenchymal tissue layer and significantly reduced p-AKT/AKT and Notch1 levels. TGF-ß1 can induce ADAMTS18 gene methylation in the postembryonic kidney, and the resulting downregulation of ADAMTS18 expression has long-term effects on kidney development, potentially leading to increased susceptibility to obstructive renal fibrosis. This mechanism may involve activation of the AKT/Notch pathway. Reversing ADAMTS18 gene methylation may reverse this process.


Asunto(s)
Proteínas ADAMTS , Enfermedades Renales , Obstrucción Ureteral , Animales , Ratas , Fibrosis , Riñón , Enfermedades Renales/metabolismo , Metilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Obstrucción Ureteral/metabolismo , Obstrucción Ureteral/patología , Proteínas ADAMTS/genética
8.
Molecules ; 29(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38474566

RESUMEN

In light of industrial developments, water pollution by heavy metals as hazardous chemicals has garnered attention. Addressing the urgent need for efficient heavy metal removal from aqueous environments, this study delves into using poly-γ-glutamic acid (γ-PGA) for the bioflocculation of heavy metals. Utilizing γ-PGA variants from Bacillus subtilis with different molecular weights and salt forms (Na-bonded and Ca-bonded), the research evaluates their adsorption capacities for copper (Cu), lead (Pb), and cadmium (Cd) ions. It was found that Na-bonded γ-PGA with a high molecular weight showed the highest heavy metal adsorption (92.2-98.3%), particularly at a 0.5% concentration which exhibited the highest adsorption efficiency. Additionally, the study investigated the interaction of γ-PGA in mixed heavy metal environments, and it was discovered that Na-γ-PGA-HM at a 0.5% concentration showed a superior adsorption efficiency for Pb ions (85.4%), highlighting its selectivity as a potential effective biosorbent for wastewater treatment. This research not only enlightens the understanding of γ-PGA's role in heavy metal remediation but also underscores its potential as a biodegradable and non-toxic alternative for environmental cleanup. The findings pave the way for further exploration into the mechanisms and kinetics of γ-PGA's adsorption properties.


Asunto(s)
Metales Pesados , Ácido Poliglutámico/análogos & derivados , Contaminantes Químicos del Agua , Cadmio/química , Ácido Glutámico , Plomo , Peso Molecular , Metales Pesados/química , Agua , Iones , Cloruro de Sodio , Adsorción , Concentración de Iones de Hidrógeno , Cinética
9.
Molecules ; 29(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38257342

RESUMEN

Resveratrol (RSV), obtained from dietary sources, has been shown to reduce trimethylamine oxide (TMAO) levels in humans, and much research indicates that TMAO is recognized as a risk factor for cardiovascular disease. Therefore, this study investigated the effects of RSV and RSV-butyrate esters (RBE) on the proliferation of co-cultured bacteria and HepG2 cell lines, respectively, and also investigated the changes in trimethylamine (TMA) and TMOA content in the medium and flavin-containing monooxygenase-3 (FMO3) gene expression. This study revealed that 50 µg/mL of RBE could increase the population percentage of Bifidobacterium longum at a rate of 53%, while the rate was 48% for Clostridium asparagiforme. In contrast, co-cultivation of the two bacterial strains effectively reduced TMA levels from 561 ppm to 449 ppm. In addition, regarding TMA-induced HepG2 cell lines, treatment with 50 µM each of RBE, 3,4'-di-O-butanoylresveratrol (ED2), and 3-O-butanoylresveratrol (ED4) significantly reduced FMO3 gene expression from 2.13 to 0.40-1.40, which would also contribute to the reduction of TMAO content. This study demonstrated the potential of RBE, ED2, and ED4 for regulating TMA metabolism in microbial co-cultures and cell line cultures, which also suggests that the resveratrol derivative might be a daily dietary supplement that will be beneficial for health promotion in the future.


Asunto(s)
Butiratos , Ésteres , Metilaminas , Humanos , Butiratos/farmacología , Estudios de Factibilidad , Resveratrol/farmacología
10.
Compr Rev Food Sci Food Saf ; 23(5): e13413, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39137001

RESUMEN

The food industry is a significant contributor to carbon emissions, impacting carbon footprint (CF), specifically during the heat drying process. Conventional heat drying processes need high energy and diminish the nutritional value and sensory quality of food. Therefore, this study aimed to investigate the integration of artificial intelligence (AI) in food processing to enhance quality and reduce CF, with a focus on heat drying, a high energy-consuming method, and offer a promising avenue for the industry to be consistent with sustainable development goals. Our finding shows that AI can maintain food quality, including nutritional and sensory properties of dried products. It determines the optimal drying temperature for improving energy efficiency, yield, and life cycle cost. In addition, dataset training is one of the key challenges in AI applications for food drying. AI needs a vast and high-quality dataset that directly impacts the performance and capabilities of AI models to optimize and automate food drying.


Asunto(s)
Inteligencia Artificial , Huella de Carbono , Manipulación de Alimentos , Calidad de los Alimentos , Calor , Manipulación de Alimentos/métodos , Desecación/métodos
11.
Opt Express ; 31(7): 11561-11577, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37155789

RESUMEN

Quantum squeezing-assisted noise suppression is a promising field with wide applications. However, the limit of noise suppression induced by squeezing is still unknown. This paper discusses this issue by studying weak signal detection in an optomechanical system. By solving the system dynamics in the frequency domain, we analyze the output spectrum of the optical signal. The results show that the intensity of the noise depends on many factors, including the degree or direction of squeezing and the choice of the detection scheme. To measure the effectiveness of squeezing and to obtain the optimal squeezing value for a given set of parameters, we define an optimization factor. With the help of this definition, we find the optimal noise suppression scheme, which can only be achieved when the detection direction exactly matches the squeezing direction. The latter is not easy to adjust as it is susceptible to changes in dynamic evolution and sensitive to parameters. In addition, we find that the additional noise reaches a minimum when the cavity (mechanical) dissipation κ(γ) satisfies the relation κ = Nγ, which can be understood as the restrictive relationship between the two dissipation channels induced by the uncertainty relation. Furthermore, by taking into account the noise source of our system, we can realize high-level noise suppression without reducing the input signal, which means that the signal-to-noise ratio can be further improved.

12.
Cancer Cell Int ; 23(1): 231, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798649

RESUMEN

OBJECTIVES: RAD51 overexpression has been reported to serve as a marker of poor prognosis in several cancer types. This study aimed to survey the role of RAD51 in oral squamous cell carcinoma and whether RAD51 could be a potential therapeutic target. MATERIALS AND METHODS: RAD51 protein expression, assessed by immunohistochemical staining, was used to examine associations with survival and clinicopathological profiles of patients with oral squamous cell carcinoma. Lentiviral infection was used to knock down or overexpress RAD51. The influence of RAD51 on the biological profile of oral cancer cells was evaluated. Cell viability and apoptosis after treatment with chemotherapeutic agents and irradiation were analyzed. Co-treatment with chemotherapeutic agents and B02, a RAD51 inhibitor, was used to examine additional cytotoxic effects. RESULTS: Oral squamous cell carcinoma patients with higher RAD51 expression exhibited worse survival, especially those treated with adjuvant chemotherapy and radiotherapy. RAD51 overexpression promotes resistance to chemotherapy and radiotherapy in oral cancer cells in vitro. Higher tumorsphere formation ability was observed in RAD51 overexpressing oral cancer cells. However, the expression of oral cancer stem cell markers did not change in immunoblotting analysis. Co-treatment with RAD51 inhibitor B02 and cisplatin, compared with cisplatin alone, significantly enhanced cytotoxicity in oral cancer cells. CONCLUSION: RAD51 is a poor prognostic marker for oral squamous cell carcinoma. High RAD51 protein expression associates with resistance to chemotherapy and radiotherapy. Addition of B02 significantly increased the cytotoxicity of cisplatin. These findings suggest that RAD51 protein may function as a treatment target for oral cancer. TRIAL REGISTRATION: Number: KMUHIRB-E(I)-20190009 Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, approved on 20190130, Retrospective registration.

13.
Crit Rev Food Sci Nutr ; : 1-17, 2023 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-37303155

RESUMEN

Fenugreek (Trigonella foenum-graecum L.) is a pharmaceutically significant aromatic crop with health benefits linked to its phytochemicals. This article aims to overview progress in using emerging technologies to extract its bioactive compounds and extraction mechanisms. Also, the trends in the applications of this herb in the food industry and its therapeutical effects were explained. Fenugreek's flavor is the primary reason for its applications in the food industry. At the same time, it has antimicrobial, antibacterial, hepatoprotection, anticancer, lactation, and antidiabetic effects. Phytochemicals responsible for these effects include galactomannans, saponins, alkaloids, and polyphenols. Besides, data showed that emerging technologies boost fenugreek extracts' yield and biological activity. Among these, ultrasound (55.6%) is the most studied technology, followed by microwave (37.0%), cold plasma (3.7%), and combined approaches (3.7%). Processing conditions (e.g., treatment time and intensity) and solvent (type, ratio, and concentration) are significant parameters that affect the performance of these novel extraction technologies. Extracts obtained by sustainable energy-saving emerging technologies can be used to develop value-added health-promoting products.


Fenugreek's phytochemicals (e.g., galactomannans and polyphenols) have therapeutic effectsUltrasound and microwave are major emerging technologies for fenugreek's bioactive compound extractionEmerging technologies enhance the yield and biological activities of fenugreek extractsEmerging extraction technologies can develop fenugreek-based products with health benefits.

14.
Environ Sci Technol ; 57(48): 20206-20218, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37965750

RESUMEN

In the realm of wastewater treatment, the power of ferrate (Fe(VI)) and peracetic acid (PAA) as oxidants stands out. But their combined might is where the enhancement truly lies. Their collaborative effect intensifies, but the underlying mechanics, especially across varying pH levels and pollutant types, still lurks in obscurity. Our study delved into the sophisticated oxidation interplay among Fe(VI)-PAA, Fe(VI)-H2O2, and standalone Fe(VI) systems. Notably, at a pH of 9.0, boasting a kinetic constant of ∼0.127 M-1·s-1, the Fe(VI)-PAA system annihilated the pollutant sulfamethoxazole, outpacing its counterparts by a staggering 48.73-fold when compared to the Fe(VI)-H2O2 system and 105.58-fold when using Fe(VI) individually. The behavior of active species─such as the dynamic •OH radicals and high-valent iron species (Fe(IV)/Fe(V))─shifted with pH variations, leading to distinct degradation pathways. Our detailed exploration pinpoints the behaviors of certain species across pH levels from 3.0 to 9.0. In more acidic environments, the •OH species proved indispensable for the system's reactivity. Conversely, as the pH inclined, degradation was increasingly steered by high-valent iron species. This intensive probe demystifies Fe(VI) interactions, deepening our understanding of the capabilities of the Fe(VI)-centered system and guiding us toward cleaner water solutions. Importantly, pH value, often underappreciated, holds the reins in organic wastewater decontamination. Embracing this key player is vital as we strategize for more expansive systems in upcoming ventures.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Ácido Peracético , Peróxido de Hidrógeno , Contaminantes Químicos del Agua/análisis , Hierro , Oxidación-Reducción , Sulfonamidas , Sulfanilamida , Concentración de Iones de Hidrógeno , Antibacterianos
15.
Phys Chem Chem Phys ; 25(12): 8507-8514, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36883477

RESUMEN

In a solution of sorbitol (SBT) and Ga(OTf)3 compounds, the coordination of sorbitol (SBT) to [Ga(OTf)n]3-n (n = 0-3) has been investigated, using both ESI-MS spectra and density functional theory (DFT) calculations at the M06/6-311++g(d,p), aug-cc-pvtz level using a polarized continuum model (PCM-SMD). In sorbitol solution, the most stable conformer of sorbitol includes three intramolecular H-bonds, i.e., O2H⋯O4, O4H⋯O6, and O5H⋯O3. Through ESI-MS spectra, in a tetrahydrofuran solution of both SBT and Ga(OTf)3 compounds, five main species are observed, i.e., [Ga(SBT)]3+, [Ga(OTf)]2+, [Ga(SBT)2]3+, [Ga(OTf)(SBT)]2+, and [Ga(OTf)(SBT)2]2+. Through DFT calculations, in a solution of sorbitol (SBT) and Ga(OTf)3 compounds, the Ga3+ cation tends to form five six-coordination complexes, i.e., [Ga(η2O,O-OTf)3], [Ga(η3O2-O4-SBT)2]3+, [(η2O,O-OTf)Ga(η4O2-O5-SBT)]2+, [(η1O-OTf)(η2O2,O4-SBT)Ga(η3O3-O5-SBT)]2+, and [(η1O-OTf)(η2O,O-OTf)Ga(η3O3-O5-SBT)]+, which are in good agreement with the experimental observation of the ESI-MS spectra. For both [Ga(OTf)n]3-n (n = 1-3) and [Ga(SBT)m]3+ (m = 1, 2) complexes, the negative charge transfer from ligands to the Ga3+-center plays an important role in their stability, because of the strong polarization of the Ga3+ cation. For [Ga(OTf)n(SBT)m]3-n (n = 1, 2; m = 1, 2) complexes, the negative charge transfer from ligands to the Ga3+-center plays an essential role in their stability, accompanied by an electrostatic interaction between the Ga3+-center and ligands and/or spatial inclusion of ligands toward the Ga3+-center.

16.
J Phys Chem A ; 127(31): 6400-6411, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37498222

RESUMEN

Al-containing catalysts, e.g., Al(OTf)3, show good catalytic performance toward the conversion of cellulose to fructose in methanol solution. Here, we report the catalytic isomerization and alcoholysis mechanisms for the conversion of cellobiose to fructose at the PBE0/6-311++G(d,p), aug-cc-pVTZ theoretical level, combining the relevant experimental verifications of electrospray ionization mass spectrometry (ESI-MS), high-performance liquid chromatography (HPLC), and the attenuated total reflection-infrared (ATR-IR) spectra. From the alcoholysis of Al(OTf)3 in methanol solution, the catalytically active species involves both the [CH3OH2]+ Brønsted acid and the [Al(CH3O)(OTf)(CH3OH)4]+ Lewis acid. There are two reaction pathways, i.e., one through glucose (glycosidic bond cleavage followed by isomerization, w-G) and another through cellobiulose (isomerization followed by glycosidic bond cleavage, w-L). The Lewis acid ([Al(CH3O)(OTf)(CH3OH)4]+) is responsible for the aldose-ketose tautomerization, while the Brønsted acid ([CH3OH2]+) is in charge of ring-opening, ring-closure, and glycosidic bond cleavage. For both w-G and w-L, the rate-determining steps are related to the intramolecular [1,2]-H shift between C1-C2 for the aldose-ketose tautomerization catalyzed by the [Al(CH3O)(OTf)(CH3OH)4]+ species. The Lewis acid ([Al(CH3O)(OTf)(CH3OH)4]+) exhibits higher catalytic activity toward the aldose-ketose tautomerization of glycosyl-chain-glucose to glycosyl-chain-fructose than that of chain-glucose to chain-fructose. Besides, the Brønsted acid ([CH3OH2]+) shows higher catalytic activity toward the glycosidic bond cleavage of cellobiulose than that of cellobiose. Kinetically, the w-L pathway is predominant, whereas the w-G pathway is minor. The theoretically proposed mechanism has been experimentally testified. These insights may advance on the novel design of the catalytic system toward the conversion of cellulose to fructose.

17.
Langenbecks Arch Surg ; 408(1): 183, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37154945

RESUMEN

PURPOSE: Positive lymph node (LN) is a key prognostic factor in radically resected gallbladder cancer (GBCA). However, only a few underwent an adequate lymphadenectomy, and the number and extent of lymph node dissection (LND) have not been standardized. This study aims to develop an en bloc and standardized surgical procedure of LND for GBCA under laparoscopy. METHODS: Data of patients with GBCA underwent laparoscopic radical resection using a standardized and en bloc technique for LND were collected. Perioperative and long-term outcomes were retrospectively analyzed. RESULTS: A total of 39 patients underwent laparoscopic radical resection using standardized and en bloc technique for LND except one case (open conversion rate: 2.6%). Patients with stage T1b had significantly lower LNs involved rate than patients with stage T3 (P = 0.04), whereas median LN count in stage T1b was significantly higher than that in stage T2 (P = 0.04), which was significantly higher than that in stage T3 (P = 0.02). Lymphadenectomy with ≥ 6 LNs accounted for 87.5% in stage T1b, up to 93.3% in T2 and 81.3% in T3, respectively. All the patients in stage T1b were alive without recurrence at this writing. The 2-year recurrence-free survival rate was 80% for T2 and 25% for T3, and the 3-year overall survival rate was 73.3% for T2 and 37.5% for T3. CONCLUSION: The standardized and en bloc LND permits complete and radical removal of lymph stations for patients with GBCA. This technique is safe and feasible with low complication rates and good prognosis. Further studies are required to explore its value and long-term outcomes compared to conventional approaches.


Asunto(s)
Neoplasias de la Vesícula Biliar , Laparoscopía , Humanos , Estudios Retrospectivos , Estadificación de Neoplasias , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología
18.
Oral Dis ; 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37448179

RESUMEN

OBJECTIVES: Previously, we demonstrated that IL17RB plays an essential role in lung cancer progression. This study aimed to determine whether IL17RB correlates with oral cancer and promotes oral cancer progression. SUBJECTS AND METHODS: IL17RB expression in oral cancer tissues and normal tissues was determined by immunohistochemistry staining, while the association of IL17RB expression with the clinicopathological characteristics of oral squamous cell carcinoma (OSCC) patients was analyzed and its correlation with progression-free survival and response to radiotherapy and chemotherapy in OSCC patients was also explored. Western blotting was performed to investigate the expression of IL17RB in various OSCC cell lines; moreover, transwell assay was performed to evaluate the effect of IL17RB expression on cell migration ability. RESULTS: In this study, we found that IL17RB was expressed higher in OSCC tissues compared to normal oral mucosa tissues and its expression was positively correlated with tumor size, lymph node metastasis, advanced cancer stage, and poor prognosis. In vitro study showed that IL17RB expression in OSCC cell lines as determined by Western blotting, was positively correlated with their migration ability. CONCLUSION: Clinical and in vitro studies suggest that IL17RB might serve as an independent risk factor and a therapeutic target for oral cancer.

19.
Sleep Breath ; 27(4): 1325-1332, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36272057

RESUMEN

OBJECTIVE: This study aimed to explore the relationship between patients with obstructive sleep apnea (OSA) from subgroups of varying severity and substantia nigra (SN) hyperechogenicity as well as cerebral blood flow detected by transcranial sonography (TCS). The study also explored if there were differences in damage of the SN and in the cerebral blood flow between the bilateral sides. METHODS: Right-handed men diagnosed with OSA by polysomnography were recruited from August 2018 to August 2020. The included patients were divided into 3 subgroups (mild, moderate, and severe OSA), and all patients underwent TCS. RESULTS: Among the 157 study patients (30 with mild OSA, 25 moderate, and 102 severe), the overall prevalence of SN hyperechogenicity was 15% (23/157). The hyperechogenicity detection rates were 3% (4/157) in the right SN subgroup and 13% (20/157) in the left SN subgroup, which were significantly different. The left side always had reduced blood flow on TCS (P < 0.05). No correlation was observed between the severity of OSA and the detection rates of SN hyperechogenicity (P > 0.05). CONCLUSION: Patients with OSA showed a higher detection rate of SN hyperechogenicity on the left compared with the right side. The left middle cerebral arteries had reduced blood flow, which was consistent with the more severe damage of the left SN. No relationship was observed between the severity of OSA and the detection rate of SN hyperechogenicity or hemodynamic parameters.


Asunto(s)
Apnea Obstructiva del Sueño , Ultrasonografía Doppler Transcraneal , Masculino , Humanos , Ultrasonografía Doppler Transcraneal/métodos , Ultrasonografía , Sustancia Negra , Apnea Obstructiva del Sueño/diagnóstico por imagen
20.
Pestic Biochem Physiol ; 197: 105651, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072526

RESUMEN

Solenopsis invicta is a main issue in southern China and is causing significant damage to the local ecological environment. The extensive use of insecticides has resulted in the development of tolerance in S. invicta. In our study, ten S. invicta colonies from Sichuan Province exhibited varying degrees of tolerance against flonicamid, with LC50 values from 0.49 mg/L to 8.54 mg/L. The sensitivity of S. invicta to flonicamid significantly increased after treatment with the P450 enzyme inhibitor piperonyl butoxide (PBO). Additionally, the activity of P450 in S. invicta was significantly enhanced after being treated with flonicamid. Flonicamid induced the expression levels of CYP4aa1, CYP9e2, CYP4C1, and CYP6A14. The expression levels of these P450 genes were significantly higher in the tolerant colonies compared to the sensitive colonies, and the relative copy numbers of CYP6A14 in the tolerant colonies were 2.01-2.15 fold. RNAi feeding treatment effectively inhibited the expression of P450 genes, thereby reducing the tolerance of S. invicta against flonicamid. In addition, the overexpression of CYP6A14 in D. melanogaster resulted in reduced sensitivity to flonicamid. Our investigations revealed hydrophobic interactions between flonicamid and seven amino acid residues of CYP6A14, along with the formation of a hydrogen bond between Glu306 and flonicamid. Our findings suggest that flonicamid can effectively control S. invicta and P450 plays a pivotal role in the tolerance of S. invicta against flonicamid. The overexpression of CYP6A14 also increased tolerance to flonicamid.


Asunto(s)
Hormigas , Insecticidas , Animales , Hormigas de Fuego , Drosophila melanogaster , Insecticidas/toxicidad
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