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1.
Patterns (N Y) ; 5(8): 101007, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39233689

RESUMO

Reconstructing neuronal morphology is vital for classifying neurons and mapping brain connectivity. However, it remains a significant challenge due to its complex structure, dense distribution, and low image contrast. In particular, AI-assisted methods often yield numerous errors that require extensive manual intervention. Therefore, reconstructing hundreds of neurons is already a daunting task for general research projects. A key issue is the lack of specialized training for challenging regions due to inadequate data and training methods. This study extracted 2,800 challenging neuronal blocks and categorized them into multiple density levels. Furthermore, we enhanced images using an axial continuity-based network that improved three-dimensional voxel resolution while reducing the difficulty of neuron recognition. Comparing the pre- and post-enhancement results in automatic algorithms using fluorescence micro-optical sectioning tomography (fMOST) data, we observed a significant increase in the recall rate. Our study not only enhances the throughput of reconstruction but also provides a fundamental dataset for tangled neuron reconstruction.

2.
bioRxiv ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39253431

RESUMO

HIV-1 envelope glycoproteins (Env) from primary HIV-1 isolates typically adopt a pretriggered "closed" conformation that resists to CD4-induced (CD4i) non-neutralizing antibodies (nnAbs) mediating antibody-dependent cellular cytotoxicity (ADCC). CD4-mimetic compounds (CD4mcs) "open-up" Env allowing binding of CD4i nnAbs, thereby sensitizing HIV-1-infected cells to ADCC. Two families of CD4i nnAbs, the anti-cluster A and anti-coreceptor binding site (CoRBS) Abs, are required to mediate ADCC in combination with the indane CD4mc BNM-III-170. Recently, new indoline CD4mcs with improved potency and breadth have been described. Here, we show that the lead indoline CD4mc, CJF-III-288, sensitizes HIV-1-infected cells to ADCC mediated by anti-CoRBS Abs alone, contributing to improved ADCC activity. Structural and conformational analyses reveal that CJF-III-288, in combination with anti-CoRBS Abs, potently stabilizes an asymmetric "open" State-3 Env conformation, This Env conformation orients the anti-CoRBS Ab to improve ADCC activity and therapeutic potential.

3.
Comput Methods Programs Biomed ; 256: 108392, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39226842

RESUMO

A deep understanding of neuron structure and function is crucial for elucidating brain mechanisms, diagnosing and treating diseases. Optical microscopy, pivotal in neuroscience, illuminates neuronal shapes, projections, and electrical activities. To explore the projection of specific functional neurons, scientists have been developing optical-based multimodal imaging strategies to simultaneously capture dynamic in vivo signals and static ex vivo structures from the same neuron. However, the original position of neurons is highly susceptible to displacement during ex vivo imaging, presenting a significant challenge for integrating multimodal information at the single-neuron level. This study introduces a graph-model-based approach for cell image matching, facilitating precise and automated pairing of sparsely labeled neurons across different optical microscopic images. It has been shown that utilizing neuron distribution as a matching feature can mitigate modal differences, the high-order graph model can address scale inconsistency, and the nonlinear iteration can resolve discrepancies in neuron density. This strategy was applied to the connectivity study of the mouse visual cortex, performing cell matching between the two-photon calcium image and the HD-fMOST brain-wide anatomical image sets. Experimental results demonstrate 96.67% precision, 85.29% recall rate, and 90.63% F1 Score, comparable to expert technicians. This study builds a bridge between functional and structural imaging, offering crucial technical support for neuron classification and circuitry analysis.


Assuntos
Neurônios , Animais , Camundongos , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Microscopia/métodos , Reconhecimento Automatizado de Padrão , Algoritmos , Imagem Multimodal/métodos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem
4.
Environ Sci Technol ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39288224

RESUMO

The nonradical oxidation pathway for pollutant degradation in Fenton-like catalysis is favorable for water treatment due to the high reaction rate and superior environmental robustness. However, precise regulation of such reactions is still restricted by our poor knowledge of underlying mechanisms, especially the correlation between metal site conformation of metal atom clusters and pollutant degradation behaviors. Herein, we investigated the electron transfer and pollutant oxidation mechanisms of atomic-level exposed Ag atom clusters (AgAC) loaded on specifically crafted nitrogen-doped porous carbon (NPC). The AgAC triggered a direct electron transfer (DET) between the terminal oxygen (Oα) of surface-activated peroxodisulfate and the electron-donating substituents-containing contaminants (EDTO-DET), rendering it 11-38 times higher degradation rate than the reported carbon-supported metal catalysts system with various single-atom active centers. Heterocyclic substituents and electron-donating groups were more conducive to degradation via the EDTO-DET system, while contaminants with high electron-absorbing capacity preferred the radical pathway. Notably, the system achieved 79.5% chemical oxygen demand (COD) removal for the treatment of actual pharmaceutical wastewater containing 1053 mg/L COD within 30 min. Our study provides valuable new insights into the Fenton-like reactions of metal atom cluster catalysts and lays an important basis for revolutionizing advanced oxidation water purification technologies.

5.
Adv Sci (Weinh) ; : e2403067, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39234800

RESUMO

To investigate how cell elongation impacts extracellular electron transfer (EET) of electroactive microorganisms (EAMs), the division of model EAM Shewanella oneidensis (S. oneidensis) MR-1 is engineered by reducing the formation of cell divisome. Specially, by blocking the translation of division proteins via anti-sense RNAs or expressing division inhibitors, the cellular length and output power density are all increased. Electrophysiological and transcriptomic results synergistically reveal that the programmed cell elongation reinforces EET by enhancing NADH oxidation, inner-membrane quinone pool, and abundance of c-type cytochromes. Moreover, cell elongation enhances hydrophobicity due to decreased cell-surface polysaccharide, thus facilitates the initial surface adhesion stage during biofilm formation. The output current and power density all increase in positive correction with cellular length. However, inhibition of cell division reduces cell growth, which is then restored by quorum sensing-based dynamic regulation of cell growth and elongation phases. The QS-regulated elongated strain thus enables a cell length of 143.6 ± 40.3 µm (72.6-fold of that of S. oneidensis MR-1), which results in an output power density of 248.0 ± 10.6 mW m-2 (3.41-fold of that of S. oneidensis MR-1) and exhibits superior potential for pollutant treatment. Engineering cellular length paves an innovate avenue for enhancing the EET of EAMs.

6.
Medicine (Baltimore) ; 103(36): e39484, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39252329

RESUMO

Mining and updating the post-marketing safety signals of esketamine nasal spray for better identification of adverse drug event (ADE) signals and medication monitoring during clinical use to ensure patient medication safety. Downloading data from the US Food and Drug Administration Adverse Event Reporting System from Q1 2019 to Q2 2023, the reporting odds ratio, proportional reporting ratio, Multi-item Gamma Poisson Shrinker, and Bayesian Confidence Propagation Neural Network methods of the disproportionality method were used to mine and analyze ADEs, and finally to screen for signals of ADEs with esketamine nasal spray as the primary suspected drug. The Preferred Terminology of the Medical Dictionary of Regulatory Activities (version 26.0) was used to standardize the description of ADEs and to attribute ADEs to the System Organ Classification. A total of 5132 ADEs reports of esketamine nasal spray as the primary suspected drug were obtained from the Food and Drug Administration Adverse Event Reporting System. The most frequently observed ADEs are dissociation, sedation, and hypertension, while some new rare signals have been detected, such as interstitial cystitis, substance abuse, and drug diversion. The present study identified significant new ADEs signals for esketamine nasal spray, which may provide a source for healthcare professionals to assess patients' symptoms and risk identification.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Ketamina , Sprays Nasais , Farmacovigilância , Humanos , Ketamina/efeitos adversos , Ketamina/administração & dosagem , Estados Unidos , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , United States Food and Drug Administration , Teorema de Bayes , Adolescente , Adulto Jovem
7.
Science ; 385(6710): 757-765, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39146425

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein binds the receptor angiotensin converting enzyme 2 (ACE2) and drives virus-host membrane fusion through refolding of its S2 domain. Whereas the S1 domain contains high sequence variability, the S2 domain is conserved and is a promising pan-betacoronavirus vaccine target. We applied cryo-electron tomography to capture intermediates of S2 refolding and understand inhibition by antibodies to the S2 stem-helix. Subtomogram averaging revealed ACE2 dimers cross-linking spikes before transitioning into S2 intermediates, which were captured at various stages of refolding. Pan-betacoronavirus neutralizing antibodies targeting the S2 stem-helix bound to and inhibited refolding of spike prehairpin intermediates. Combined with molecular dynamics simulations, these structures elucidate the process of SARS-CoV-2 entry and reveal how pan-betacoronavirus S2-targeting antibodies neutralize infectivity by arresting prehairpin intermediates.


Assuntos
Enzima de Conversão de Angiotensina 2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Simulação de Dinâmica Molecular , Domínios Proteicos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/química , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/química , Internalização do Vírus , Redobramento de Proteína , Tomografia com Microscopia Eletrônica , Multimerização Proteica , Betacoronavirus/imunologia , Betacoronavirus/química , Membrana Celular/metabolismo , COVID-19/virologia , COVID-19/imunologia , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo
8.
Front Neurol ; 15: 1432966, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39161872

RESUMO

Background: The question of whether a correlation exists between migraine and five psychiatric disorders, including posttraumatic stress disorder (PTSD), major depressive disorder (MDD), anorexia nervosa (AN), bipolar disorder (BIP), and schizophrenia (SCZ), remains a matter of controversy. Hence, this research aims to investigate whether there is a possible association between migraine and five psychiatric disorders. Methods: We performed a bidirectional 2-sample Mendelian randomization (MR) analysis to assess the causality between migraine and five psychiatric disorders. Genetic associations of PTSD, MDD, AN, BIP, and SCZ were obtained from the Psychiatric Genomics Consortium (PGC) database and genetic associations of migraine with aura and migraine without aura were obtained from the FinnGen dataset. We used the inverse-variance weighted (IVW), weighted median, weighted mode, MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO), and MR Egger regression methods to evaluate the association of genetically predicted exposure with the risk of outcome. Results: MR demonstrated that MDD was associated with a high risk of migraine without aura (OR = 1.930578, 95% confidence interview (CI): 1.224510, 3.043550, p < 0.05), but BIP was related to a low risk of migraine without aura (OR = 0.758650, 95%CI: 0.639601, 0.899858, p < 0.05). According to the results of reverse MR, migraine with aura was associated with a high risk of BIP (OR = 1.019100, 95%CI: 1.002538, 1.035935, p < 0.05), and migraine without aura was associated with an increased risk of AN (OR = 1.055634, 95%CI: 1.023859, 1.088394, p < 0.05). Conclusion: Our results provide evidence of the potential causal association between migraine and some psychiatric disorders. It may contribute to the prevention of migraine and some psychiatric disorders.

10.
Polymers (Basel) ; 16(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39125155

RESUMO

The formation of polylactide stereocomplex (sc-PLA), involving the blending of poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA), enhances PLA materials by making them stronger and more heat-resistant. This study investigated the competitive crystallization behavior of homocrystals (HCs) and stereocomplex crystals (SCs) in a 50/50 PLLA/PDLA blend with added polyethylene glycol (PEG). PEG, with molecular weights of 400 g/mol and 35,000 g/mol, was incorporated at concentrations ranging from 5% to 20% by weight. Differential scanning calorimetry (DSC) analysis revealed that PEG increased the crystallization temperature, promoted SC formation, and inhibited HC formation. PEG also acted as a plasticizer, lowering both melting and crystallization temperatures. The second heating DSC curve showed that the pure PLLA/PDLA blend had a 57.1% fraction of SC while adding 5% PEG with a molecular weight of 400 g/mol resulted in complete SC formation. In contrast, PEG with a molecular weight of 35,000 g/mol was less effective, allowing some HC formation. Additionally, PEG consistently promoted SC formation across various cooling rates (2, 5, 10, or 20 °C/min), demonstrating a robust influence under different conditions.

11.
Molecules ; 29(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998922

RESUMO

Volatile organic compounds (VOCs) are a class of hazardous gases that are widely present in the atmosphere and cause great harm to human health. In this paper, a ratiometric fluorescent probe (Dye@Eu-MOFs) based on a dye-functionalized metal-organic framework was designed to detect VOCs, which showed high sensitivity and specificity for acetaldehyde solution and vapor. A linear correlation between the integrated fluorescence intensity (I510/I616) and the concentration of acetaldehyde was investigated, enabling a quantitative analysis of acetaldehyde in the ranges of 1 × 10-4~10-5 µL/mL, with a low detection limit of 8.12 × 10-4 mg/L. The selective recognition of acetaldehyde could be clearly distinguished by the naked eye under the excitation of UV light. The potential sensing mechanism was also discussed. Significantly, a molecular logic gate was constructed based on the whole system, and finally, a molecular logic network system for acetaldehyde detection connecting basic and integrated logic operations was realized. This strategy provided an effective guiding method for constructing a molecular-level logic gate for acetaldehyde detection on a simple platform.

12.
Acta Pharm Sin B ; 14(6): 2773-2785, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828142

RESUMO

Although sulfonation plays crucial roles in various biological processes and is frequently utilized in medicinal chemistry to improve water solubility and chemical diversity of drug leads, it is rare and underexplored in ribosomally synthesized and post-translationally modified peptides (RiPPs). Biosynthesis of RiPPs typically entails modification of hydrophilic residues, which substantially increases their chemical stability and bioactivity, albeit at the expense of reducing water solubility. To explore sulfonated RiPPs that may have improved solubility, we conducted co-occurrence analysis of RiPP class-defining enzymes and sulfotransferase (ST), and discovered two distinctive biosynthetic gene clusters (BGCs) encoding both lanthipeptide synthetase (LanM) and ST. Upon expressing these BGCs, we characterized the structures of novel sulfonated lanthipeptides and determined the catalytic details of LanM and ST. We demonstrate that SslST-catalyzed sulfonation is leader-independent but relies on the presence of A ring formed by LanM. Both LanM and ST are promiscuous towards residues in the A ring, but ST displays strict regioselectivity toward Tyr5. The recognition of cyclic peptide by ST was further discussed. Bioactivity evaluation underscores the significance of the ST-catalyzed sulfonation. This study sets up the starting point to engineering the novel lanthipeptide STs as biocatalysts for hydrophobic lanthipeptides improvement.

13.
Nat Commun ; 15(1): 5314, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38906879

RESUMO

The introduction of single-atom catalysts (SACs) into Fenton-like oxidation promises ultrafast water pollutant elimination, but the limited access to pollutants and oxidant by surface catalytic sites and the intensive oxidant consumption still severely restrict the decontamination performance. While nanoconfinement of SACs allows drastically enhanced decontamination reaction kinetics, the detailed regulatory mechanisms remain elusive. Here, we unveil that, apart from local enrichment of reactants, the catalytic pathway shift is also an important cause for the reactivity enhancement of nanoconfined SACs. The surface electronic structure of cobalt site is altered by confining it within the nanopores of mesostructured silica particles, which triggers a fundamental transition from singlet oxygen to electron transfer pathway for 4-chlorophenol oxidation. The changed pathway and accelerated interfacial mass transfer render the nanoconfined system up to 34.7-fold higher pollutant degradation rate and drastically raised peroxymonosulfate utilization efficiency (from 61.8% to 96.6%) relative to the unconfined control. It also demonstrates superior reactivity for the degradation of other electron-rich phenolic compounds, good environment robustness, and high stability for treating real lake water. Our findings deepen the knowledge of nanoconfined catalysis and may inspire innovations in low-carbon water purification technologies and other heterogeneous catalytic applications.

14.
J Colloid Interface Sci ; 672: 383-391, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38848622

RESUMO

Electrocatalytic nitrate removal offers a sustainable approach to alleviate nitrate pollution and to boost the anthropogenic nitrogen cycle, but it still suffers from limited removal efficiency at high rates, especially at low levels of nitrate. Herein, we report the near-complete removal of low-level nitrate (10-200 ppm) within 2 h using ultrathin cobalt-based nanosheets (CoNS) containing surface oxygen, which was fabricated from in-situ electrochemical reconstruction of conventional nanosheets. The average nitrate removal of 99.7 % with ammonia selectivity of 98.2 % in 9 cyclic runs ranked in the best of reported catalysts. Powered by a solar cell under the winter sun, the full-cell nitrate electrolysis system, equipped with ultrathin CoNS, achieved 100 % nitrogen gas selectivity and 99.6 % total nitrogen removal. The in-situ Fourier Transform Infrared included experiments and theoretical computations revealed that in-situ electrochemical reconstruction not only increased electrochemical active surface area but also constructed surface oxygen in active sites, leading to enhanced stabilization of nitrate adsorption in a symmetry breaking configuration and charge transfer, contributing to near-complete nitrate removal on ultrathin CoNS. This work provides a strategy to design ultrathin nanocatalysts for nitrate removal.

15.
Neurosci Bull ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819707

RESUMO

Knowledge about the neuronal dynamics and the projectome are both essential for understanding how the neuronal network functions in concert. However, it remains challenging to obtain the neural activity and the brain-wide projectome for the same neurons, especially for neurons in subcortical brain regions. Here, by combining in vivo microscopy and high-definition fluorescence micro-optical sectioning tomography, we have developed strategies for mapping the brain-wide projectome of functionally relevant neurons in the somatosensory cortex, the dorsal hippocampus, and the substantia nigra pars compacta. More importantly, we also developed a strategy to achieve acquiring the neural dynamic and brain-wide projectome of the molecularly defined neuronal subtype. The strategies developed in this study solved the essential problem of linking brain-wide projectome to neuronal dynamics for neurons in subcortical structures and provided valuable approaches for understanding how the brain is functionally organized via intricate connectivity patterns.

16.
Fish Shellfish Immunol ; 150: 109622, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38740227

RESUMO

The voltage-dependent anion channel 2 (VDAC2) is the abundant protein in the outer mitochondrial membrane. Opening VDAC2 pores leads to the induction of mitochondrial energy and material transport, facilitating interaction with various mitochondrial proteins implicated in essential processes such as cell apoptosis and proliferation. To investigate the VDAC2 in lower vertebrates, we identified Lr-VDAC2, a homologue of VDAC2 found in lamprey (Lethenteron reissneri), sharing a sequence identity of greater than 50 % with its counterparts. Phylogenetic analysis revealed that the position of Lr-VDAC2 aligns with the lamprey phylogeny, indicating its evolutionary relationship within the species. The Lr-VDAC2 protein was primarily located in the mitochondria of lamprey cells. The expression of the Lr-VDAC2 protein was elevated in high energy-demanding tissues, such as the gills, muscles, and myocardial tissue in normal lampreys. Lr-VDAC2 suppressed H2O2 (hydrogen peroxide)-induced 293 T cell apoptosis by reducing the expression levels of Caspase 3, Caspase 9, and Cyt C (cytochrome c). Further research into the mechanism indicated that the Lr-VDAC2 protein inhibited the pro-apoptotic activity of BAK (Bcl-2 antagonist/killer) protein by downregulating its expression at the protein translational level, thus exerting an anti-apoptotic function similar to the role of VDAC2 in humans.


Assuntos
Apoptose , Proteínas de Peixes , Lampreias , Canal de Ânion 2 Dependente de Voltagem , Animais , Humanos , Sequência de Aminoácidos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Regulação da Expressão Gênica , Células HEK293 , Peróxido de Hidrogênio , Lampreias/genética , Lampreias/imunologia , Filogenia , Alinhamento de Sequência/veterinária , Canal de Ânion 2 Dependente de Voltagem/metabolismo
17.
Metab Eng ; 83: 206-215, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38710300

RESUMO

Shewanella oneidensis MR-1 has found widespread applications in pollutant transformation and bioenergy production, closely tied to its outstanding heme synthesis capabilities. However, this significant biosynthetic potential is still unexploited so far. Here, we turned this bacterium into a highly-efficient bio-factory for green synthesis of 5-Aminolevulinic Acid (5-ALA), an important chemical for broad applications in agriculture, medicine, and the food industries. The native C5 pathway genes of S. oneidensis was employed, together with the introduction of foreign anti-oxidation module, to establish the 5-ALA production module, resulting 87-fold higher 5-ALA yield and drastically enhanced tolerance than the wild type. Furthermore, the metabolic flux was regulated by using CRISPR interference and base editing techniques to suppress the competitive pathways to further improve the 5-ALA titer. The engineered strain exhibited 123-fold higher 5-ALA production capability than the wild type. This study not only provides an appealing new route for 5-ALA biosynthesis, but also presents a multi-dimensional modularized engineering strategy to broaden the application scope of S. oneidensis.


Assuntos
Ácido Aminolevulínico , Engenharia Metabólica , Shewanella , Shewanella/genética , Shewanella/metabolismo , Ácido Aminolevulínico/metabolismo
18.
Front Bioeng Biotechnol ; 12: 1392414, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605985

RESUMO

Succinic acid (SA), one of the 12 top platform chemicals produced from biomass, is a precursor of various high value-added derivatives. Specially, 1 mol CO2 is assimilated in 1 mol SA biosynthetic route under anaerobic conditions, which helps to achieve carbon reduction goals. In this review, methods for enhanced CO2 fixation in SA production and utilization of waste biomass for SA production are reviewed. Bioelectrochemical and bioreactor coupling systems constructed with off-gas reutilization to capture CO2 more efficiently were highlighted. In addition, the techno-economic analysis and carbon sequestration benefits for the synthesis of bio-based SA from CO2 and waste biomass are analyzed. Finally, a droplet microfluidics-based high-throughput screening technique applied to the future bioproduction of SA is proposed as a promising approach.

19.
Environ Sci Technol ; 58(17): 7291-7301, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38623940

RESUMO

The environmental dissemination of extracellular antibiotic resistance genes (eARGs) in wastewater and natural water bodies has aroused growing ecological concerns. The coexisting chemical pollutants in water are known to markedly affect the eARGs transfer behaviors of the environmental microbial community, but the detailed interactions and specific impacts remain elusive so far. Here, we revealed a concentration-dependent impact of dimethyl phthalate (DMP) and several other types of phthalate esters (common water pollutants released from plastics) on the natural transformation of eARGs. The DMP exposure at an environmentally relevant concentration (10 µg/L) resulted in a 4.8-times raised transformation frequency of Acinetobacter baylyi but severely suppressed the transformation at a high concentration (1000 µg/L). The promotion by low-concentration DMP was attributed to multiple mechanisms, including increased bacterial mobility and membrane permeability to facilitate eARGs uptake and improved resistance of the DMP-bounded eARGs (via noncovalent interaction) to enzymatic degradation (with suppressed DNase activity). Similar promoting effects of DMP on the eARGs transformation were also found in real wastewater and biofilm systems. In contrast, higher-concentration DMP suppressed the eARGs transformation by disrupting the DNA structure. Our findings highlight a potentially underestimated eARGs spreading in aquatic environments due to the impacts of coexisting chemical pollutants and deepen our understanding of the risks of biological-chemical combined pollution in wastewater and environmental water bodies.


Assuntos
Resistência Microbiana a Medicamentos , Ácidos Ftálicos , Resistência Microbiana a Medicamentos/genética , Águas Residuárias , Biofilmes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
20.
Regen Biomater ; 11: rbae008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545260

RESUMO

Collagen, the most abundant structural protein in the human extracellular matrix (ECM), provides essential support for tissues and guides tissue development. Despite its widespread use in tissue engineering, there remains uncertainty regarding the optimal selection of collagen sources. Animal-derived sources pose challenges such as immunogenicity, while the recombinant system is hindered by diminished bioactivity. In this study, we hypothesized that human ECM-like collagen (hCol) could offer an alternative for tissue engineering. In this study, a facile platform was provided for generating hCol derived from mesenchymal stem cells with a hierarchical structure and biochemical properties resembling native collagen. Our results further demonstrated that hCol could facilitate basal biological behaviors of human adipose-derived stem cells, including viability, proliferation, migration and adipocyte-like phenotype. Additionally, it could promote cutaneous wound closure. Due to its high similarity to native collagen and good bioactivity, hCol holds promise as a prospective candidate for in vitro and in vivo applications in tissue engineering.

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