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1.
Sci Rep ; 14(1): 15008, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951644

RESUMEN

This work introduces and discusses the impacts of the water bridge on gas adsorption and diffusion behaviors in a shale gas-bearing formation. The density distribution of the water bridge has been analyzed in micropores and meso-slit by molecular dynamics. Na+ and Cl- have been introduced into the system to mimic a practical encroachment environment and compared with pure water to probe the deviation in water bridge distribution. Additionally, practical subsurface scenarios, including pressure and temperature, are examined to reveal the effects on gas adsorption and diffusion properties, determining the shale gas transportation in realistic shale formation. The outcomes suggest carbon dioxide (CO2) usually has higher adsorption than methane (CH4) with a water bridge. Increasing temperature hinders gas adsorption, density distribution decreases in all directions. Increasing pressure facilitates gas adsorption, particularly as a bulk phase in the meso-slit, whereas it restricts gas diffusion by enhancing the interaction strength between gas and shale. Furthermore, ions make the water bridge distributes more unity and shifts to the slit center, impeding gas adsorption onto shale while encouraging gas diffusion. This study provides updated guidelines for gas adsorption and transportation characteristics and supports the fundamental understanding of industrial shale gas exploration and transportation.

2.
Front Aging Neurosci ; 16: 1399285, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38979112

RESUMEN

Aim: To investigate the correlation between motor function and health-related quality of life (HrQOL) in early to mid-stage patients with Parkinson disease (PwP). Methods: This cross-sectional study recruited PwP from April 2020 to December 2023 at the outpatient clinic of Peking Union Medical College Hospital in Beijing, China. The motor symptoms were assessed using Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part 3. Balance function was evaluated using the Berg Balance Scale (BBS), and the risk of fall using Timed Up-and-Go test (TUG), and Five Times Sit-to-Stand test (FTSST). Freezing of gait questionnaire (FOGQ) was used to evaluate the severity of gait. The Intelligent Device for Energy Expenditure and Physical Activity (IDEEA) recorded gait cycle parameters, and the isokinetic dynamometer measured muscle strength. The Parkinson's Disease Questionnaire-39 (PDQ-39) was used to measure HrQOL. All assessments were tested during the on state. Spearman correlation was conducted to evaluate the correlation between motor function and HrQOL. Results: 243 patients with mean age of 69.33 years were enrolled. The PDQ-39 score was strongly correlated with FOG in H&Y stage III (r = 0.653, p < 0.001) and moderately correlated in H&Y stage I (r = 0.471, p < 0.001) and H&Y stage II (r = 0.386, p < 0.001). Furthermore, the FOG was strongly correlated with mobility domain at H&Y stage III (r = 0.694, p < 0.001) and moderately correlated at H&Y stage I (r = 0.431, p < 0.001) and H&Y stage II (r = 0.434, p < 0.001). All motor function scores were correlated with PDQ-39 scores at H&Y stage III (p < 0.05). Conclusion: Motor function correlated with HrQOL in early to mid-stage PwP, and FOG was the main factor, especially affecting mobility, activities of daily life and communication. HrQOL in patients at different disease stages were variously affected by motor function, and HrQOL and multiple dimensions was significantly associated with motor function in patients at H&Y stage III.

3.
Nurse Educ ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38981035

RESUMEN

BACKGROUND: The performance of GPT-4 in nursing examinations within the Chinese context has not yet been thoroughly evaluated. OBJECTIVE: To assess the performance of GPT-4 on multiple-choice and open-ended questions derived from nursing examinations in the Chinese context. METHODS: The data sets of the Chinese National Nursing Licensure Examination spanning 2021 to 2023 were used to evaluate the accuracy of GPT-4 in multiple-choice questions. The performance of GPT-4 on open-ended questions was examined using 18 case-based questions. RESULTS: For multiple-choice questions, GPT-4 achieved an accuracy of 71.0% (511/720). For open-ended questions, the responses were evaluated for cosine similarity, logical consistency, and information quality, all of which were found to be at a moderate level. CONCLUSION: GPT-4 performed well at addressing queries on basic knowledge. However, it has notable limitations in answering open-ended questions. Nursing educators should weigh the benefits and challenges of GPT-4 for integration into nursing education.

4.
Front Pharmacol ; 15: 1374607, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38994206

RESUMEN

Background: Lianhua Qingwen (LHQW) granule, a botanical drug preparation, is frequently utilized as an adjuvant treatment for mycoplasma pneumoniae pneumonia (MPP). Nevertheless, the clinical efficacy and safety of this treatment remain uncertain. Purpose: This study aims to evaluate the efficacy and safety of LHQW granule combined with azithromycin (AZM) in treating MPP in children. Method: To identify all randomized controlled trials (RCTs) of LHQW granule plus AZM, a search was conducted in eight Chinese and English databases (CNKI, Wan Fang, VIP, Sinomed, PubMed, Embase, Web of Science, and Cochrane Library) from their inception until 25 December 2023. Meta-regression and subgroup analysis were employed to investigate heterogeneity. Sensitivity analysis and trial sequential analysis (TSA) were conducted to assess the robustness of the findings. Additionally, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was utilized to evaluate the quality of evidence. Results: A total of 15 RCTs involving 1909 participants were included in this study. The meta-analysis results indicated combination therapy of LHQW granule and AZM is significant different from AZM alone in both efficacy and safety, which are specifically observed in the following outcomes: response rate (RR = 1.17, 95% CI: 1.12 to 1.22, p < 0.01), antipyretic time (MD = -1.32, 95% CI: -1.66 to -0.98, p < 0.01), cough disappearance time (MD = -1.76, 95% CI: -2.47 to -1.05, p < 0.01), pulmonary rale disappearance time (MD = -1.54, 95% CI: -2.06 to -1.02, p < 0.01), c-reactive protein (CRP) (MD = -5.50, 95% CI: -6.92 to -4.07, p < 0.01), procalcitonin (PCT) (MD = -0.31, 95% CI: -0.38 to -0.24, p < 0.01), interleukin 6 (IL-6) (MD = -5.97, 95% CI: -7.39 to -4.54, p<0.01), tumor necrosis factor α (TNF-α) (MD = -5.74, 95% CI: -7.44 to -4.04, p < 0.01), forced vital capacity (FVC) (SMD = 0.48, 95% CI: 0.34 to 0.62, p < 0.01), forced expiratory volume in the first second (FEV1) (SMD = 0.55, 95% CI: 0.44 to 0.67, p < 0.01), FEV1/FVC (SMD = 0.49, 95% CI: 0.32 to 0.67, p < 0.01), CD4+ T lymphocyte (CD4+) (MD = 4.04, 95% CI: 3.09 to 4.98, p < 0.01), CD8+ T lymphocyte (CD8+) (MD = -3.32, 95% CI: 4.27 to 2.38, p < 0.01) and adverse events (RR = 0.65, 95% CI: 0.43 to 0.96, p < 0.01). Conclusion: The combination therapy of LHQW granule and AZM may be a better strategy to treat MPP in children. However, the clinical efficacy and safety of LHQW granule require further validation. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/.

5.
Nat Commun ; 15(1): 5998, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39013916

RESUMEN

Using renewable electricity to convert CO2 into CO offers a sustainable route to produce a versatile intermediate to synthesize various chemicals and fuels. For economic CO2-to-CO conversion at scale, however, there exists a trade-off between selectivity and activity, necessitating the delicate design of efficient catalysts to hit the sweet spot. We demonstrate here that copper co-alloyed with isolated antimony and palladium atoms can efficiently activate and convert CO2 molecules into CO. This trimetallic single-atom alloy catalyst (Cu92Sb5Pd3) achieves an outstanding CO selectivity of 100% (±1.5%) at -402 mA cm-2 and a high activity up to -1 A cm-2 in a neutral electrolyte, surpassing numerous state-of-the-art noble metal catalysts. Moreover, it exhibits long-term stability over 528 h at -100 mA cm-2 with an FECO above 95%. Operando spectroscopy and theoretical simulation provide explicit evidence for the charge redistribution between Sb/Pd additions and Cu base, demonstrating that Sb and Pd single atoms synergistically shift the electronic structure of Cu for CO production and suppress hydrogen evolution. Additionally, the collaborative interactions enhance the overall stability of the catalyst. These results showcase that Sb/Pd-doped Cu can steadily carry out efficient CO2 electrolysis under mild conditions, challenging the monopoly of noble metals in large-scale CO2-to-CO conversion.

6.
Front Cell Infect Microbiol ; 14: 1411249, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39035351

RESUMEN

Breast cancer (BrCa) is the most prevalent malignant tumor in women and one of the leading causes of female mortality. Its occurrence and progression are influenced by various factors, including genetics, environment, lifestyle, and hormones. In recent years, the gut microbiota has been identified as a significant factor affecting BrCa. The gut microbiota refers to the collective population of various microorganisms in the human gastrointestinal tract. Gut microbiota is closely associated with human health and disease development, participating in crucial physiological functions such as digestion, metabolism, immune response, and neural regulation. It has been found to influence the occurrence and treatment of BrCa through a variety of mechanisms. This article aims to review the immunomodulatory role of the gut microbiota in the development and treatment of BrCa.


Asunto(s)
Neoplasias de la Mama , Progresión de la Enfermedad , Microbioma Gastrointestinal , Humanos , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/microbiología , Neoplasias de la Mama/terapia , Femenino , Incidencia , Inmunomodulación
7.
Cancer Cell Int ; 24(1): 236, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970092

RESUMEN

Chemotherapy is currently one of the most effective methods in clinical cancer treatment. However, chemotherapy resistance is an important reason for poor chemotherapy efficacy and prognosis, which has become an urgent problem to be solved in the field of cancer chemotherapy. Therefore, it is very important to deeply study and analyze the mechanism of cancer chemotherapy resistance and its regulatory factors. Long non-coding RNA nuclear paraspeckle assembly transcript 1 (LncRNA NEAT1) has been shown to be closely associated with chemotherapy resistance in cancer. NEAT1 induces cancer cell resistance to chemotherapeutic drugs by regulating cell apoptosis, cell cycle, drug transport and metabolism, DNA damage repair, EMT, autophagy, cancer stem cell characteristics, and metabolic reprogramming. This indicates that NEAT1 may be an important target to overcome chemotherapy resistance and is expected to be a potential biomarker to predict the effect of chemotherapy. This article summarizes the expression characteristics and clinical characteristics of NEAT1 in different cancers, and deeply discusses the regulatory role of NEAT1 in cancer chemotherapy resistance and related molecular mechanisms, aiming to clarify NEAT1 as a new target to overcome cancer chemotherapy resistance and the feasibility of chemotherapy sensitizers, with a view to providing a potential therapeutic direction for overcoming the dilemma of cancer resistance in the future.

8.
Mikrochim Acta ; 191(8): 470, 2024 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023769

RESUMEN

A CRISPR/Cas12a-coupled multiplexed strand displacement amplification (CMSDA) for the detection of miR155 has been developed. Non-specific amplification was avoided by designing a single-stranded DNA template with a hairpin structure. The detection target miR155 was used as a primer to initiate a multiple-strand displacement reaction to produce abundant ssDNA. ssDNA was recognized by the Cas12a/CrRNA binary complex, activating the trans-cleaving activity of Cas12a. The multiple-strand displacement reaction is more efficiently detected compared with a single-strand displacement reaction. The detection range is from 250 pM to 1 nM, and the limit of the detection is 6.5 pM. The proposed method showed a good applicability in complex serum environments, indicating that the method has a broad prospect for disease detection and clinical application. In addition, we designed a dual-cavity PCR tube, which realized one-tube detection of miRNA155 and avoided open-cap contamination.


Asunto(s)
Sistemas CRISPR-Cas , MicroARNs , MicroARNs/análisis , MicroARNs/sangre , MicroARNs/genética , Humanos , Sistemas CRISPR-Cas/genética , ADN de Cadena Simple/química , ADN de Cadena Simple/genética , Límite de Detección , Técnicas de Amplificación de Ácido Nucleico/métodos , Reacción en Cadena de la Polimerasa/métodos , Proteínas Bacterianas , Endodesoxirribonucleasas , Proteínas Asociadas a CRISPR
9.
Front Microbiol ; 15: 1423951, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027091

RESUMEN

Introduction: A variety of studies have shown a link between the gut microbiota and autoimmune diseases, but the causal relationship with Henoch-Schönlein purpura (HSP) and immune thrombocytopenic purpura (ITP) is unknown. Methods: This study investigated the bidirectional causality between gut microbiota and HSP and ITP using Mendelian randomization (MR). Large-scale genetic data of gut microbiota at phylum to species level from the MiBioGen consortium and the Dutch Microbiome Project were utilized. Genome-wide association studies (GWAS) summary statistics for HSP and ITP came from FinnGen R10. Various MR methods were applied to infer causal relationships, including inverse variance weighted (IVW), maximum likelihood (ML), cML-MA, MR-Egger, weighted median, weighted model, and MR-PRESSO. Multiple sensitivity analyses and Bonferroni correction were conducted to enhance robustness and reliability. Results: Based on the IVW estimates, 23 bacterial taxa were identified to have suggestive associations with HSP and ITP. Remarkably, after Bonferroni correction, family Alcaligenaceae (OR = 2.86, 95% CI = 1.52-5.37; IVW, p = 1.10 × 10-3, ML, p = 1.40 × 10-3) was significantly associated with ITP as a risk factor, while family Bacteroidales S24 7group (OR = 0.46, 95% CI = 0.29-0.74; IVW, p = 1.40 × 10-3) was significantly associated with ITP as a protective factor. No significant associations between HSP and ITP and gut microbiota were found in reverse analyses. Conclusion: Our study provides evidence of causal effects of gut microbiota on HSP and ITP, highlighting the importance of further research to clarify the underlying mechanisms and develop targeted therapeutic interventions for these autoimmune diseases.

10.
Autophagy ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38873928

RESUMEN

Osteopenia and osteoporosis are among the most common metabolic bone diseases and represent major public health problems, with sufferers having an increased fracture risk. Diabetes is one of the most common diseases contributing to osteopenia and osteoporosis. However, the mechanisms underlying diabetes-induced osteopenia and osteoporosis remain unclear. Bone reconstruction, including bone formation and absorption, is a dynamic process. Large-conductance Ca2+-activated K+ channels (BK channels) regulate the function of bone marrow-derived mesenchymal stem cells, osteoblasts, and osteoclasts. Our previous studies revealed the relationship between BK channels and the function of osteoblasts via various pathways under physiological conditions. In this study, we reported a decrease in the expression of BK channels in mice with diabetes-induced osteopenia. BK deficiency enhanced mitochondrial Ca2+ and activated classical PINK1 (PTEN induced putative kinase 1)-PRKN/Parkin (parkin RBR E3 ubiquitin protein ligase)-dependent mitophagy, whereas the upregulation of BK channels inhibited mitophagy in osteoblasts. Moreover, SLC25A5/ANT2 (solute carrier family 25 (mitochondrial carrier, adenine nucleotide translocator), member 5), a critical inner mitochondrial membrane protein participating in PINK1-PRKN-dependent mitophagy, was also regulated by BK channels. Overall, these data identified a novel role of BK channels in regulating mitophagy in osteoblasts, which might be a potential target for diabetes-induced bone diseases.

11.
Sci Adv ; 10(26): eado4390, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941471

RESUMEN

Light-driven oxidative coupling of methane (OCM) for multi-carbon (C2+) product evolution is a promising approach toward the sustainable production of value-added chemicals, yet remains challenging due to its low intrinsic activity. Here, we demonstrate the integration of bismuth oxide (BiOx) and gold (Au) on titanium dioxide (TiO2) substrate to achieve a high conversion rate, product selectivity, and catalytic durability toward photocatalytic OCM through rational catalytic site engineering. Mechanistic investigations reveal that the lattice oxygen in BiOx is effectively activated as the localized oxidant to promote methane dissociation, while Au governs the methyl transfer to avoid undesirable overoxidation and promote carbon─carbon coupling. The optimal Au/BiOx-TiO2 hybrid delivers a conversion rate of 20.8 millimoles per gram per hour with C2+ product selectivity high to 97% in the flow reactor. More specifically, the veritable participation of lattice oxygen during OCM is chemically looped by introduced dioxygen via the Mars-van Krevelen mechanism, endowing superior catalyst stability.

12.
Anal Chem ; 96(26): 10577-10585, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38887964

RESUMEN

Simultaneous detection of multiple breast cancer-associated miRNAs significantly raises the accuracy and reliability of early diagnosis. In this work, disposable carbon fiber paper serves as the biosensing interface, linking DNA probes via click chemistry to efficiently capture targets and signals efficiently. DNA probes have multiple recognition domains that trigger a cascade reaction through the helper probes and targets, resulting in two signals output. The signals are centrally encapsulated in the pore of the MIL-88(Fe)-NH2. The signal carriers are directed by signal probes to the recognition domains that correspond to the DNA probes. The biosensor is selective and stable, and it can quantify miRNA-21 and miRNA-155 simultaneously with detection limits of 0.64 and 0.54 fmol/L, respectively. Furthermore, it demonstrates satisfactory performance in tests conducted with normal human serum and cell lysate. Overall, this method makes a satisfactory exploration to realize an inexpensive and sensitive biosensor for multiple biomarkers.


Asunto(s)
Técnicas Biosensibles , Química Clic , MicroARNs , Técnicas Biosensibles/métodos , Humanos , MicroARNs/análisis , MicroARNs/sangre , Sondas de ADN/química , Neoplasias de la Mama/diagnóstico , Límite de Detección
13.
Langmuir ; 40(26): 13622-13635, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38904387

RESUMEN

Carbon dioxide (CO2) injection in unconventional gas-bearing shale reservoirs is a promising method for enhancing methane recovery efficiency and mitigating greenhouse gas emissions. The majority of methane is adsorbed within the micropores and nanopores (≤50 nm) of shale, which possess extensive surface areas and abundant adsorption sites for the sequestration system. To comprehensively discover the underlying mechanism of enhanced gas recovery (EGR) through CO2 injection, molecular dynamics (MD) provides a promising way for establishing the shale models to address the multiphase, multicomponent fluid flow behaviors in shale nanopores. This study proposes an innovative method for building a more practical shale matrix model that approaches natural underground environments. The grand canonical Monte Carlo (GCMC) method elucidates gas adsorption and sequestration processes in shale gas reservoirs under various subsurface conditions. The findings reveal that previously overlooked pore slits have a significant impact on both gas adsorption and recovery efficiency. Based on the simulation comparisons of absolute and excess uptakes inside the kerogen matrix and the shale slits, it demonstrates that nanopores within the kerogen matrix dominate the gas adsorption while slits dominate the gas storage. Regarding multiphase, multicomponent fluid flow in shale nanopores, moisture negatively influences gas adsorption and carbon storage while promoting methane recovery efficiency by CO2 injection. Additionally, saline solution and ethane further impede gas adsorption while facilitating displacement. Overall, this work elucidates the substantial effect of CO2 injection on fluid transport in shale formations and advances the comprehensive understanding of microscopic gas flow and recovery mechanisms with atomic precision for low-carbon energy development.

14.
Int J Biol Macromol ; 273(Pt 2): 133063, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38880443

RESUMEN

The oral delivery of doxorubicin (DOX), an anti-cancer drug, encounters multiple hurdles such as limited gastrointestinal permeability, P-glycoprotein-mediated efflux, brief intestinal residence, and rapid degradation. This study introduced a novel approach utilizing hyaluronic acid (HA)-grafted fatty acid monoglycerides (HGD) to encapsulate DOX, forming HGD-DOX nanoparticles, aimed at enhancing its oral bioavailability. Drug encapsulated by HGD provided several advantages, including extended drug retention in the gastrointestinal tract, controlled release kinetics, and promotion of lymphatic absorption in the intestine. Additionally, HGD-DOX nanoparticles could specifically target CD44 receptors, potentially increasing therapeutic efficacy. The uptake mechanism of HGD-DOX nanoparticles primarily involved clathrin-mediated, caveolin-mediated and macropinocytosis endocytosis. Pharmacokinetic analysis further revealed that HGD significantly prolonged the in vivo residence time of DOX. In vivo imaging and pharmacodynamic studies indicated that HGD possessed tumor-targeting capabilities and exhibited a significant inhibitory effect on tumor growth, while maintaining an acceptable safety profile. Collectively, these findings position HGD-DOX nanoparticles as a promising strategy to boost the oral bioavailability of DOX, offering a potential avenue for improved cancer treatment.


Asunto(s)
Doxorrubicina , Receptores de Hialuranos , Ácido Hialurónico , Nanopartículas , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Ácido Hialurónico/química , Animales , Nanopartículas/química , Receptores de Hialuranos/metabolismo , Humanos , Administración Oral , Ratones , Portadores de Fármacos/química , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Nat Commun ; 15(1): 5059, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871727

RESUMEN

Sclerotinia stem rot (SSR), caused by the necrotrophic fungus Sclerotinia sclerotiorum, is one of the most devastating diseases for several major oil-producing crops. Despite its impact, the genetic basis of SSR resistance in plants remains poorly understood. Here, through a genome-wide association study, we identify a key gene, BnaA07. MKK9, that encodes a mitogen-activated protein kinase kinase that confers SSR resistance in oilseed rape. Our functional analyses reveal that BnaA07.MKK9 interacts with BnaC03.MPK3 and BnaC03.MPK6 and phosphorylates them at the TEY activation motif, triggering a signaling cascade that initiates biosynthesis of ethylene, camalexin, and indole glucosinolates, and promotes accumulation of H2O2 and the hypersensitive response, ultimately conferring resistance. Furthermore, variations in the coding sequence of BnaA07.MKK9 alter its kinase activity and improve SSR resistance by ~30% in cultivars carrying the advantageous haplotype. These findings enhance our understanding of SSR resistance and may help engineer novel diversity for future breeding of oilseed rape.


Asunto(s)
Ascomicetos , Brassica napus , Resistencia a la Enfermedad , Estudio de Asociación del Genoma Completo , Enfermedades de las Plantas , Proteínas de Plantas , Ascomicetos/genética , Ascomicetos/patogenicidad , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brassica napus/microbiología , Brassica napus/genética , Brassica napus/inmunología , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Regulación de la Expresión Génica de las Plantas , Fosforilación , Variación Genética
16.
J Org Chem ; 89(12): 9011-9018, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38847456

RESUMEN

C-O bond formation via C-H alkoxylation remains a challenge, especially coupling with a secondary alcohol, due to its low activity and sterically encumbered property. Here, we report a general and effective cobalt-catalyzed oxidative cross-coupling of benzamides with secondary alcohols via C-H alkoxylation reaction under solvothermal conditions, enabled by a salicylaldehyde/cobalt complex. The protocol features easy operation without additives, broad substrate scope, and excellent functional tolerance. The applicability is proven by the gram-scale synthesis and modification of natural products.

17.
ACS Synth Biol ; 13(6): 1916-1924, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38861476

RESUMEN

Betanin is a water-soluble red-violet pigment belonging to the betacyanins family. It has become more and more attractive for its natural food colorant properties and health benefits. However, the commercial production of betanin, typically extracted from red beetroot, faces economic and sustainability challenges. Microbial heterologous production therefore offers a promising alternative. Here, we performed combinatorial engineering of plant P450 enzymes and precursor metabolisms to improve the de novo production of betanin in Saccharomyces cerevisiae. Semirational design by computer simulation and molecular docking was used to improve the catalytic activity of CYP76AD. Alanine substitution and site-directed saturation mutants were screened, with a combination mutant showing an approximately 7-fold increase in betanin titer compared to the wild type. Subsequently, betanin production was improved by enhancing the l-tyrosine pathway flux and UDP-glucose supply. Finally, after optimization of the fermentation process, the engineered strain BEW10 produced 134.1 mg/L of betanin from sucrose, achieving the highest reported titer of betanin in a shake flask by microbes. This work shows the P450 enzyme and metabolic engineering strategies for the efficient microbial production of natural complex products.


Asunto(s)
Betacianinas , Sistema Enzimático del Citocromo P-450 , Ingeniería Metabólica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Betacianinas/metabolismo , Betacianinas/biosíntesis , Ingeniería Metabólica/métodos , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Simulación del Acoplamiento Molecular , Fermentación
18.
Water Res ; 259: 121896, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38865914

RESUMEN

The electro-peroxone (EP) process encounters two inherent challenges in wastewater treatment: sluggish O2/O3 transfer and substantial ozone waste. To overcome these limitations, we introduced micro-nano bubbles (MNBs) aeration to enhance O2/O3 dissolution and diffusion, ultimately aiming to improve the removal of trace pharmaceutical contaminants from hospital wastewater. In the MNBs aeration system, the ozone transfer coefficient ranging from 0.536 to 0.265 min-1, significantly surpassing that of conventional aeration (0.220 to 0.090 min-1) by approximately 2 to 4.5 times. Consequently, the EP process under MNBs aeration significantly enhanced ozone-resistant ibuprofen (IBU) removal, achieving a removal rate of 98.4 ± 1.5 %, far exceeding the 47.3 ± 4.7 % observed with conventional aeration. This significant improvement was attributed to the heightened production of hydroxyl radicals (•OH), reaching 0.97 × 10-9 M s, compared to only 0.28 × 10-9 M s in conventional aeration. The mechanism behind the enhanced •OH production in the MNBs-EP process relied primarily on two factors: improved O2/O3 dissolution due to high internal pressure/large surface and enhanced O3/H2O2 activation from high collapse energy. These factors together contributed to the robust oxidation capability of the MNBs-EP system. As a result, over 97 % removal efficiency was achieved for five representative pharmaceutical pollutants (sulfamethoxazole, ribavirin, norfloxacin, tetracycline and ampicillin) in just 1 min. Furthermore, when applied to real hospital wastewater, the MNBs-O3-E treatment system reduced all 15 detected trace pharmaceutical compounds to below 10 ng L-1 and achieved 14 types of pollutants with removal rates of over 85 % within 15 min, resulting in an ultrahigh total removal rate of 98.6 %, from an initial total concentration of 2108 ng L-1 to less than 30 ng L-1. Thus, micro-nano aeration endowed the EP process as a promising advanced oxidation system for rapid and highly-effective removal of trace pharmaceutical contaminants from hospital wastewater.


Asunto(s)
Hospitales , Ozono , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , Ozono/química , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Preparaciones Farmacéuticas
20.
Opt Express ; 32(11): 19552-19566, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859088

RESUMEN

Besides the scattering structures, the energy transfer (ET) process in the gain medium plays a significant role in the competition between coherent (comprising strongly coherent components) and incoherent (consisting of weakly coherent or "hidden" coherent components) modes of random lasers. In this study, bichromatic emission random lasers were successfully created using polydimethylsiloxane (PDMS) replicas with grooved structures that imitate the inner surface of abalone shells as scattering substrates. The influence mechanism of the ET process from the monomer to dimer in the Rhodamine 640 dye on the competition of random laser modes was thoroughly investigated from both spectral and temporal dimensions. It was confirmed that the ET process can reduce the gain of monomers while amplifying the gain of dimers. By considering the dominant high-efficiency ET processes, an energy transfer factor associated with the pump energy density was determined. Notably, for the first time, it was validated that the statistical distribution characteristics of the time sequence variations in the coherent random laser generated by dimers closely resemble a normal distribution. This finding demonstrates the feasibility of producing high-quality random number sequences.

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