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1.
Nature ; 603(7899): 159-165, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35197629

RESUMEN

Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects1-4. For clinical doses of metformin, AMP-activated protein kinase (AMPK) has a major role in its mechanism of action4,5; however, the direct molecular target of metformin remains unknown. Here we show that clinically relevant concentrations of metformin inhibit the lysosomal proton pump v-ATPase, which is a central node for AMPK activation following glucose starvation6. We synthesize a photoactive metformin probe and identify PEN2, a subunit of γ-secretase7, as a binding partner of metformin with a dissociation constant at micromolar levels. Metformin-bound PEN2 forms a complex with ATP6AP1, a subunit of the v-ATPase8, which leads to the inhibition of v-ATPase and the activation of AMPK without effects on cellular AMP levels. Knockout of PEN2 or re-introduction of a PEN2 mutant that does not bind ATP6AP1 blunts AMPK activation. In vivo, liver-specific knockout of Pen2 abolishes metformin-mediated reduction of hepatic fat content, whereas intestine-specific knockout of Pen2 impairs its glucose-lowering effects. Furthermore, knockdown of pen-2 in Caenorhabditis elegans abrogates metformin-induced extension of lifespan. Together, these findings reveal that metformin binds PEN2 and initiates a signalling route that intersects, through ATP6AP1, the lysosomal glucose-sensing pathway for AMPK activation. This ensures that metformin exerts its therapeutic benefits in patients without substantial adverse effects.


Asunto(s)
Hipoglucemiantes , Metformina , ATPasas de Translocación de Protón Vacuolares , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Trifosfatasas/metabolismo , Secretasas de la Proteína Precursora del Amiloide , Animales , Caenorhabditis elegans/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Glucosa/metabolismo , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/metabolismo , Hipoglucemiantes/farmacología , Lisosomas/metabolismo , Proteínas de la Membrana , Metformina/agonistas , Metformina/metabolismo , Metformina/farmacología , ATPasas de Translocación de Protón Vacuolares/metabolismo
2.
Plant Physiol ; 195(1): 652-670, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38412470

RESUMEN

Poplar (Populus) is a well-established model system for tree genomics and molecular breeding, and hybrid poplar is widely used in forest plantations. However, distinguishing its diploid homologous chromosomes is difficult, complicating advanced functional studies on specific alleles. In this study, we applied a trio-binning design and PacBio high-fidelity long-read sequencing to obtain haplotype-phased telomere-to-telomere genome assemblies for the 2 parents of the well-studied F1 hybrid "84K" (Populus alba × Populus tremula var. glandulosa). Almost all chromosomes, including the telomeres and centromeres, were completely assembled for each haplotype subgenome apart from 2 small gaps on one chromosome. By incorporating information from these haplotype assemblies and extensive RNA-seq data, we analyzed gene expression patterns between the 2 subgenomes and alleles. Transcription bias at the subgenome level was not uncovered, but extensive-expression differences were detected between alleles. We developed machine-learning (ML) models to predict allele-specific expression (ASE) with high accuracy and identified underlying genome features most highly influencing ASE. One of our models with 15 predictor variables achieved 77% accuracy on the training set and 74% accuracy on the testing set. ML models identified gene body CHG methylation, sequence divergence, and transposon occupancy both upstream and downstream of alleles as important factors for ASE. Our haplotype-phased genome assemblies and ML strategy highlight an avenue for functional studies in Populus and provide additional tools for studying ASE and heterosis in hybrids.


Asunto(s)
Alelos , Genoma de Planta , Populus , Populus/genética , Genoma de Planta/genética , Regulación de la Expresión Génica de las Plantas , Haplotipos/genética , Hibridación Genética , Aprendizaje Automático
3.
Nat Chem Biol ; 19(7): 855-864, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36805701

RESUMEN

Tyrosine sulfation is a common posttranslational modification in mammals. To date, it has been thought to be limited to secreted and transmembrane proteins, but little is known about tyrosine sulfation on nuclear proteins. Here we report that SULT1B1 is a histone sulfotransferase that can sulfate the tyrosine 99 residue of nascent histone H3 in cytosol. The sulfated histone H3 can be transported into the nucleus and majorly deposited in the promoter regions of genes in chromatin. While the H3Y99 residue is buried inside octameric nucleosome, dynamically regulated subnucleosomal structures provide chromatin-H3Y99sulf the opportunity of being recognized and bound by PRMT1, which deposits H4R3me2a in chromatin. Disruption of H3Y99sulf reduces PRMT1 binding to chromatin, H4R3me2a level and gene transcription. These findings reveal the mechanisms underlying H3Y99 sulfation and its cross-talk with H4R3me2a to regulate gene transcription. This study extends the spectrum of tyrosine sulfation on nuclear proteins and the repertoire of histone modifications regulating chromatin functions.


Asunto(s)
Histonas , Tirosina , Animales , Histonas/metabolismo , Tirosina/genética , Cromatina , Proteínas Nucleares/metabolismo , Transcripción Genética , Mamíferos/genética
4.
Chem Soc Rev ; 53(4): 1892-1914, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38230701

RESUMEN

Molecular assembly is the process of organizing individual molecules into larger structures and complex systems. The self-assembly approach is predominantly utilized in creating artificial molecular assemblies, and was believed to be the primary mode of molecular assembly in living organisms as well. However, it has been shown that the assembly of many biological complexes is "catalysed" by other molecules, rather than relying solely on self-assembly. In this review, we summarize these catalysed-assembly (catassembly) phenomena in living organisms and systematically analyse their mechanisms. We then expand on these phenomena and discuss related concepts, including catalysed-disassembly and catalysed-reassembly. Catassembly proves to be an efficient and highly selective strategy for synergistically controlling and manipulating various noncovalent interactions, especially in hierarchical molecular assemblies. Overreliance on self-assembly may, to some extent, hinder the advancement of artificial molecular assembly with powerful features. Furthermore, inspired by the biological catassembly phenomena, we propose guidelines for designing artificial catassembly systems and developing characterization and theoretical methods, and review pioneering works along this new direction. Overall, this approach may broaden and deepen our understanding of molecular assembly, enabling the construction and control of intelligent assembly systems with advanced functionality.

5.
J Allergy Clin Immunol ; 153(4): 1025-1039, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38072196

RESUMEN

BACKGROUND: Ectopic lymphoid tissues (eLTs) and associated follicular helper T (TFH) cells contribute to local immunoglobulin hyperproduction in nasal polyps (NPs). Follicular regulatory T (TFR) cells in secondary lymphoid organs counteract TFH cells and suppress immunoglobulin production; however, the presence and function of TFR cells in eLTs in peripheral diseased tissues remain poorly understood. OBJECTIVE: We sought to investigate the presence, phenotype, and function of TFR cells in NPs. METHODS: The presence, abundance, and phenotype of TFR cells in NPs were examined using single-cell RNA sequencing, immunofluorescence staining, and flow cytometry. Sorted polyp and circulating T-cell subsets were cocultured with autologous circulating naïve B cells, and cytokine and immunoglobulin production were measured by ELISA. RESULTS: TFR cells were primarily localized within eLTs in NPs. TFR cell frequency and TFR cell/TFH cell ratio were decreased in NPs with eLTs compared with NPs without eLTs and control inferior turbinate tissues. TFR cells displayed an overlapping phenotype with TFH cells and FOXP3+ regulatory T cells in NPs. Polyp TFR cells had reduced CTLA-4 expression and decreased capacity to inhibit TFH cell-induced immunoglobulin production compared with their counterpart in blood and tonsils. Blocking CTLA-4 abolished the suppressive effect of TFR cells. Lower vitamin D receptor expression was observed on polyp TFR cells compared with TFR cells in blood and tonsils. Vitamin D treatment upregulated CTLA-4 expression on polyp TFR cells and restored their suppressive function in vitro. CONCLUSIONS: Polyp TFR cells in eLTs have decreased CLTA-4 and vitamin D receptor expression and impaired capacity to suppress TFH cell-induced immunoglobulin production, which can be reversed by vitamin D treatment in vitro.


Asunto(s)
Pólipos Nasales , Estructuras Linfoides Terciarias , Humanos , Linfocitos T Reguladores/patología , Linfocitos T Colaboradores-Inductores/patología , Antígeno CTLA-4/metabolismo , Receptores de Calcitriol/metabolismo , Pólipos Nasales/patología , Estructuras Linfoides Terciarias/patología , Inmunoglobulinas/metabolismo , Vitamina D/metabolismo
6.
J Am Chem Soc ; 146(10): 6422-6437, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38426858

RESUMEN

The development of a new catalytic strategy plays a vital role in modern organic chemistry since it permits bond formation in an unprecedented and more efficient manner. Although the application of preformed metal complexes as π-base-activated reagents have enabled diverse transformations elegantly, the concept and strategy by directly utilizing transition metals as efficient π-Lewis base catalysts remain underdeveloped, especially in the field of asymmetric catalysis. Here, we outline our perspective on the discovery of palladium(0) as an efficient π-Lewis base catalyst, which is capable of increasing the highest occupied molecular orbital (HOMO) energy of both electron-neutral and electron-deficient 1,3-dienes and 1,3-enynes upon flexible η2-complexes formed in situ and resultant π-backdonation. Thus, fruitful carbon-carbon-forming reactions with diverse electrophiles can be achieved enantioselectively in a vinylogous addition pattern, which is conceptually different from the classical oxidative cyclization mechanism. Emphasis will be given to the concept and mechanism elucidation, catalytic features, and reaction design together with perspective on the further development of this emerging field.

7.
Small ; 20(22): e2306830, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38126556

RESUMEN

Wearable thermoelectric generators (TEGs) have exhibited great potential to convert the temperature gradient between the human body and the environment into electrical energy for maintenance-free wearable applications. A 2D planar device structure is widely employed for fabricating flexible TEGs due to its simple structure and facile fabrication properties. However, this device configuration is more appropriate for utilizing in-plane temperature differences than the out-of-plane direction, which limits their application in wearable cases since the temperature difference between the human body and the environment is in the out-of-plane direction. To solve this problem, a novel fabric-based TEG structure that can utilize the out-of-plane temperature gradient is proposed in this work. By introducing thermally conductive components in the generator, the out-of-plane temperature difference can be switched to the in-plane direction, which can be further utilized for 2D planar devices in wearable applications. The prepared thermoelectric fabric prototype with only 12 p-type TE legs exhibits a maximum open-circuit voltage of 4.69 mV and an output power of 39.7 nW at a temperature difference of 30 K. This strategy exhibits a high degree of versatility and can be readily applied to other 2D planar TEGs, thus expanding their potential application in wearable technology.

8.
Small ; 20(15): e2307096, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37994304

RESUMEN

Skin wounds accompanied by bacterial infections threaten human health, and conventional antibiotic treatments are ineffective for drug-resistant bacterial infections and chronically infected wounds. The development of non-antibiotic-dependent therapeutics is highly desired but remains a challenging issue. Recently, 2D silicene nanosheets with considerable biocompatibility, biodegradability, and photothermal-conversion performance have received increasing attention in biomedical fields. Herein, copper-containing nanoparticles-loaded silicene (Cu2.8O@silicene-BSA) nanosheets with triple enzyme mimicry catalytic (peroxidase, catalase, and oxidase-like) activities and photothermal function are rationally designed and fabricated for efficient bacterial elimination, angiogenesis promotion, and accelerated wound healing. Cu2.8O@silicene-BSA nanosheets display excellent antibacterial activity through synergistic effects of reactive oxygen species generated from multiple catalytic reactions, intrinsic bactericidal activity of released Cu2+ ions, and photothermal effects, achieving high antibacterial efficiencies on methicillin-resistant Staphylococcus aureus (MRSA) of 99.1 ± 0.7% in vitro and 97.2 ± 1.6% in vivo. In addition, Cu2.8O@silicene-BSA nanosheets exhibit high biocompatibility for promoting human umbilical vein endothelial cell (HUVEC) proliferation and angiogenic differentiation. In vivo experiments reveal that Cu2.8O@silicene-BSA nanosheets with synergistic photothermal/chemodynamic therapeutics effectively accelerate MRSA-infected wound healing by eliminating bacteria, alleviating inflammation, boosting collagen deposition, and promoting angiogenesis. This research presents a promising strategy to engineer photothermal-assisted nanozyme catalysis for bacteria-invaded wound healing.


Asunto(s)
Infecciones Bacterianas , Staphylococcus aureus Resistente a Meticilina , Humanos , Cobre , Bacterias , Cicatrización de Heridas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
9.
Ann Surg Oncol ; 31(2): 838-846, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37919448

RESUMEN

BACKGROUND: This study updated 3-year analyses to further characterize the impact of docetaxel, cisplatin, and fluorouracil (TPF) chemotherapy followed by surgery. METHODS: This study was a single-center phase 2 clinical trial. Patients with a diagnosis of borderline resectable esophageal squamous cell carcinoma (BR-ESCC) because of the primary tumor or bulky lymph node that potentially invaded adjacent organs were eligible. The treatment started with TPF chemotherapy followed by surgery if the cancer was resectable, or by concurrent chemoradiation if it was unresectable. This updated report presents the 3-year overall survival (OS) and progression-free survival (PFS) rates. RESULTS: Surgery was performed for 27 patients (57.4%), and R0 resection was confirmed in 25 patients (53.2%). Pathologic complete response was confirmed in four patients (8.5%). The median follow-up time for the surviving patients was 44.8 months (range, 3.4-74.6 months). The median OS for all the patients was 41.9 months (95% confidence interval [CI], 18.6-65.3 months), with a median PFS of 38.7 months (95% CI, 23.5-53.9 months). The 3-year survival rate for all the patients was 54.4%. The 3-year survival rate for the R0 patients was 65.4%. CONCLUSION: Long-term follow-up evaluation confirmed that TPF followed by surgery is feasible and promising in terms of survival for BR-ESCC patients. Trial Registration ClinicalTrials.gov identifer: NCT02976909.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Cisplatino , Neoplasias Esofágicas/tratamiento farmacológico , Quimioterapia de Inducción , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Taxoides , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel , Fluorouracilo
10.
Opt Express ; 32(3): 4427-4435, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297644

RESUMEN

Multimode fiber lasers have become a new platform for investigating nonlinear phenomena since the report on spatiotemporal mode-locking. In this work, the multimode soliton pulsation with a tunable period is achieved in a spatiotemporal mode-locked fiber laser. It demonstrates that the pulsation period drops while increasing the pump power. Moreover, it is found that different transverse modes have the same pulsation period, asynchronous pulsation evolution and different dynamical characteristics through the spatial sampling technique and the dispersive Fourier transform technique. To further verify the experimental results, we numerically investigate the influences of the gain and the loss on the pulsation properties. It is found that within a certain parameter range, the pulsation period drops and rises linearly with the increase of the gain and the loss, respectively. The obtained results contribute to understanding the formation and regulating of soliton pulsations in fiber lasers.

11.
Opt Express ; 32(6): 10059-10067, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571226

RESUMEN

Dissipative solitons (DSs), due to the complex interplay among dispersion, nonlinear, gain and loss, illustrate abundant nonlinear dynamics behaviors. Especially, dispersion plays an important role in the research of DS dynamics in ultrafast fiber lasers. Previous studies have mainly focused on the effect of even-order dispersion, i.e., group velocity dispersion (GVD) and fourth-order dispersion. In fact, odd-order dispersions, such as third-order dispersion (TOD), also significantly influences the dynamics of DSs. However, due to the lack of dispersion engineering tools, few experimental researches in this domain have been reported. In this work, by employing a pulse shaper in ultrafast fiber laser, an in-depth exploration of the DS dynamics influenced by TOD was conducted. With the increase of TOD value, the stable single DS undergoes a splitting into two solitons and then enters explosion state, and ultimately evolves into a chaotic state. The laser operation state is correlated to dispersion profile, which could be controlled by TOD. Here, the positive dispersion at long-wavelength side will be gradually shifted to negative dispersion by increasing the TOD, where soliton effect will drive the transitions. These findings offer valuable insights into the nonlinear dynamics of ultrafast lasers and may also foster applications involving higher-order dispersion.

12.
Opt Lett ; 49(1): 57-60, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134151

RESUMEN

We develop an all polarization-maintaining (PM) 920 nm Nd-doped fiber amplifier delivering a train of pulses with ∼0.53 W average power and sub-50 fs duration. The sub-50 fs pulse benefits from the pre-chirping management method that allows for over 60 nm broadening spectrum without pulse breaking in the amplification stage. By virtue of the short pulse duration, the pulse peak power can reach to ∼0.31 MW in spite of the moderate average power. These results represent a key step in developing high-peak-power pulse Nd-doped fiber laser systems at 920 nm, which will find important applications in fields such as biomedical imaging, ultrafast optical spectroscopy, and excitation of quantum-dot single photon sources.

13.
Opt Lett ; 49(6): 1575-1578, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489454

RESUMEN

Spatiotemporal mode-locked (STML) fiber lasers have become a new platform for investigating nonlinear phenomena. In this work, spatiotemporal dual-periodic soliton pulsation (SDSP) is firstly observed in an STML fiber laser. It is found that in the SDSP, the long-period pulsations (LPPs) of different transverse modes are synchronous, while the short-period pulsations (SPPs) exhibit asynchronous modulations. The numerical simulation confirms the experimental results and further reveals that the proportion of transverse mode components can manipulate the periods of the LPP and SPP but does not affect the synchronous and asynchronous pulsations of different transverse modes. The obtained results bring the study of spatiotemporal dissipative soliton pulsation into the multi-period modulation stage, which helps to understand the complex spatiotemporal dynamics in STML fiber lasers and discover new dynamics in high-dimensional nonlinear systems.

14.
Allergy ; 79(5): 1230-1241, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38403941

RESUMEN

BACKGROUND: Identifying predictive biomarkers for allergen immunotherapy response is crucial for enhancing clinical efficacy. This study aims to identify such biomarkers in patients with allergic rhinitis (AR) undergoing subcutaneous immunotherapy (SCIT) for house dust mite allergy. METHODS: The Tongji (discovery) cohort comprised 72 AR patients who completed 1-year SCIT follow-up. Circulating T and B cell subsets were characterized using multiplexed flow cytometry before SCIT. Serum immunoglobulin levels and combined symptom and medication score (CSMS) were assessed before and after 12-month SCIT. Responders, exhibiting ≥30% CSMS improvement, were identified. The random forest algorithm and logistic regression analysis were used to select biomarkers and establish predictive models for SCIT efficacy in the Tongji cohort, which was validated in another Wisco cohort with 43 AR patients. RESULTS: Positive SCIT response correlated with higher baseline CSMS, allergen-specific IgE (sIgE)/total IgE (tIgE) ratio, and frequencies of Type 2 helper T cells, Type 2 follicular helper T (TFH2) cells, and CD23+ nonswitched memory B (BNSM) and switched memory B (BSM) cells, as well as lower follicular regulatory T (TFR) cell frequency and TFR/TFH2 cell ratio. The random forest algorithm identified sIgE/tIgE ratio, TFR/TFH2 cell ratio, and BNSM frequency as the key biomarkers discriminating responders from nonresponders in the Tongji cohort. Logistic regression analysis confirmed the predictive value of a combination model, including sIgE/tIgE ratio, TFR/TFH2 cell ratio, and CD23+ BSM frequency (AUC = 0.899 in Tongji; validated AUC = 0.893 in Wisco). CONCLUSIONS: A T- and B-cell signature combination efficiently identified SCIT responders before treatment, enabling personalized approaches for AR patients.


Asunto(s)
Biomarcadores , Desensibilización Inmunológica , Pyroglyphidae , Rinitis Alérgica , Humanos , Rinitis Alérgica/terapia , Rinitis Alérgica/inmunología , Masculino , Desensibilización Inmunológica/métodos , Animales , Femenino , Adulto , Pyroglyphidae/inmunología , Resultado del Tratamiento , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Persona de Mediana Edad , Adulto Joven , Alérgenos/inmunología , Alérgenos/administración & dosificación , Antígenos Dermatofagoides/inmunología , Inyecciones Subcutáneas , Adolescente , Pronóstico
15.
J Org Chem ; 89(6): 4098-4112, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38421813

RESUMEN

A method for the selective construction of S-N/C(sp2)-S bonds using N-substituted O-thiocarbamates and indoles as substrates is reported. This protocol features good atom utilization, mild conditions, short reaction time, and wide substrate scope, which can provide a convenient path for the functionalization of indoles. In addition, the reaction could be scaled up on gram scale, showing potential application value in industry synthesis.

16.
Inorg Chem ; 63(25): 11768-11778, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38864539

RESUMEN

The exploration of low-cost, efficient, environmentally safe, and selective catalysts for the activation of carbon-halogen bonds has become an important and challenging topic in modern chemistry. With the help of density functional theory (DFT), it is found that phenyl bromide (PhBr) can be efficiently chemisorbed by the Al12M (M = Be, Al, C, and P) superatoms via forming highly polarized Al-Br covalent bonds, where the C-Br bonds of PhBr can be effectively activated through the electron transfer from Al12M. The different electronic structures of these four Al12M superatoms pose a substantial effect on their performances on the activation of PhBr and the catalytic mechanisms of the Suzuki-Miyaura (SM) reaction. Among them, the alkali-metal-like superatom Al12P exhibits the best performance for the activation of PhBr. In particular, Al13 and Al12P with open-shell electronic structures exhibit catalytic performances comparable to those of previously reported catalysts for this coupling reaction. Hence, it is highly expected that Al13 and Al12P could be used as novel superatom catalysts for C-C coupling reactions and, therefore, open up new possibilities to use nonprecious superatoms in catalyzing the activation and transformation of carbon-halogen bonds.

17.
Org Biomol Chem ; 22(6): 1205-1212, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38224270

RESUMEN

Hydroxyl radicals (˙OH) as one of the highly reactive species can react unselectively with a wide range of chemicals. The ˙OH radicals are typically generated under harsh conditions. Herein, we report hydroxyl radical-induced selective N-α C(sp3)-H bond oxidation of amides under greener and mild conditions via an Fe(NO3)3·9H2O catalyst inner sphere pathway upon irradiation with a 30 W blue LED light strip (λ = 455 nm) using NaBrO3 as the oxidant. This protocol exhibited high chemoselectivity and excellent functional group tolerance. A preliminary mechanism investigation demonstrated that the iron catalyst afforded hydroxyl radicals via the visible-light-induced homolysis (VLIH) of iron complexes followed by a hydrogen atom transfer (HAT) process to realize this transformation.

18.
Environ Sci Technol ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900106

RESUMEN

Appropriate mixed carbon sources have great potential to enhance denitrification efficiency and reduce operational costs in municipal wastewater treatment plants (WWTPs). However, traditional methods struggle to efficiently select the optimal mixture due to the variety of compositions. Herein, we developed a machine learning-assisted high-throughput method enabling WWTPs to rapidly identify and optimize mixed carbon sources. Taking a local WWTP as an example, a mixed carbon source denitrification data set was established via a high-throughput method and employed to train a machine learning model. The composition of carbon sources and the types of inoculated sludge served as input variables. The XGBoost algorithm was employed to predict the total nitrogen removal rate and microbial growth, thereby aiding in the assessment of the denitrification potential. The predicted carbon sources exhibited an enhanced denitrification potential over single carbon sources in both kinetic experiments and long-term reactor operations. Model feature analysis shows that the cumulative effect and interaction among individual carbon sources in a mixture significantly enhance the overall denitrification potential. Metagenomic analysis reveals that the mixed carbon sources increased the diversity and complexity of denitrifying bacterial ecological networks in WWTPs. This work offers an efficient method for WWTPs to optimize mixed carbon source compositions and provides new insights into the mechanism behind enhanced denitrification under a supply of multiple carbon sources.

19.
Bioorg Chem ; 149: 107531, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38850779

RESUMEN

Nitroreductase (NTR) overexpression often occurs in tumors, highlighting the significance of effective NTR detection. Despite the utilization of various optical methods for this purpose, the absence of an efficient tumor-targeting optical probe for NTR detection remains a challenge. In this research, a novel tumor-targeting probe (Cy-Bio-NO2) is developed to perform dual-modal NTR detection using near-infrared fluorescence and photoacoustic techniques. This probe exhibits exceptional sensitivity and selectivity to NTR. Upon the reaction with NTR, Cy-Bio-NO2 demonstrates a distinct fluorescence "off-on" response at 800 nm, with an impressive detection limit of 12 ng/mL. Furthermore, the probe shows on-off photoacoustic signal with NTR. Cy-Bio-NO2 has been successfully employed for dual-modal NTR detection in living cells, specifically targeting biotin receptor-positive cancer cells for imaging purposes. Notably, this probe effectively detects tumor hypoxia through dual-modal imaging in tumor-bearing mice. The strategy of biotin incorporation markedly enhances the probe's tumor-targeting capability, facilitating its engagement in dual-modal imaging at tumor sites. This imaging capacity holds substantial promise as an accurate tool for cancer diagnosis.


Asunto(s)
Colorantes Fluorescentes , Nitrorreductasas , Imagen Óptica , Animales , Humanos , Ratones , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Ratones Endogámicos BALB C , Ratones Desnudos , Estructura Molecular , Neoplasias/diagnóstico por imagen , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/metabolismo , Nitrorreductasas/metabolismo , Nitrorreductasas/análisis , Técnicas Fotoacústicas , Dióxido de Nitrógeno/síntesis química , Dióxido de Nitrógeno/química
20.
Bioorg Chem ; 150: 107571, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38936048

RESUMEN

In recent years, Varicocele (VC) has been recognized as a common cause of male infertility that can be treated by surgery or drugs. How to reduce the damage of VC to testicular spermatogenic function has attracted extensive attention in recent years. Among them, overexpressed ROS and high levels of inflammation may play a key role in VC-induced testicular damage. As the key mediated innate immune pathways, cGAS-STING shaft under pathological conditions, such as in cell and tissue damage stress can be cytoplasmic DNA activation, induce the activation of NLRP3 inflammatory corpuscle, triggering downstream of the inflammatory cascade reaction. Chlorogenic acid (CGA), as a natural compound from a wide range of sources, has strong anti-inflammatory and antioxidant activities, and is a potential effective drug for the treatment of varicocele infertility. The aim of this study is to investigate the role of CGA in the spermatogenic dysfunction of the rat testis induced by VC and the potential mechanisms. The results of this study have shown that CGA gavage treatment ameliorated the pathological damage of seminiferous tubules, increased the number of sperm in the lumen, and increased the expression levels of Occludin and ZO-1, which indicated the therapeutic effect of CGA on spermatogenic dysfunction in the testis of VC rats. Meanwhile, the damage of mitochondrial structure was alleviated and the expression levels of ROS, NLRP3 and pro-inflammatory cytokines (IL-1ß, IL-6, IL-18) were significantly reduced in the testicular tissues of model rats after CGA treatment. In addition, we demonstrated for the first time the high expression status of cGAS and STING in testicular tissues of VC model rats, and this was ameliorated to varying degrees after CGA treatment. In conclusion, this study suggests that CGA can improve the spermatogenic function of the testis by reducing mitochondrial damage and inhibiting the activation of the cGAS-STING axis, inhibiting the activation of the NLRP3 inflammasome, and improving the inflammatory damage of the testis, highlighting the potential of CGA as a therapeutic agent for varicocele infertility.

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