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1.
Cell ; 186(3): 560-576.e17, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36693374

RESUMO

Downward social mobility is a well-known mental risk factor for depression, but its neural mechanism remains elusive. Here, by forcing mice to lose against their subordinates in a non-violent social contest, we lower their social ranks stably and induce depressive-like behaviors. These rank-decline-associated depressive-like behaviors can be reversed by regaining social status. In vivo fiber photometry and single-unit electrophysiological recording show that forced loss, but not natural loss, generates negative reward prediction error (RPE). Through the lateral hypothalamus, the RPE strongly activates the brain's anti-reward center, the lateral habenula (LHb). LHb activation inhibits the medial prefrontal cortex (mPFC) that controls social competitiveness and reinforces retreats in contests. These results reveal the core neural mechanisms mutually promoting social status loss and depressive behaviors. The intertwined neuronal signaling controlling mPFC and LHb activities provides a mechanistic foundation for the crosstalk between social mobility and psychological disorder, unveiling a promising target for intervention.


Assuntos
Habenula , Status Social , Camundongos , Animais , Recompensa , Comportamento Social , Habenula/fisiologia , Depressão
2.
Nat Immunol ; 25(2): 268-281, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38195702

RESUMO

Melanoma cells, deriving from neuroectodermal melanocytes, may exploit the nervous system's immune privilege for growth. Here we show that nerve growth factor (NGF) has both melanoma cell intrinsic and extrinsic immunosuppressive functions. Autocrine NGF engages tropomyosin receptor kinase A (TrkA) on melanoma cells to desensitize interferon γ signaling, leading to T and natural killer cell exclusion. In effector T cells that upregulate surface TrkA expression upon T cell receptor activation, paracrine NGF dampens T cell receptor signaling and effector function. Inhibiting NGF, either through genetic modification or with the tropomyosin receptor kinase inhibitor larotrectinib, renders melanomas susceptible to immune checkpoint blockade therapy and fosters long-term immunity by activating memory T cells with low affinity. These results identify the NGF-TrkA axis as an important suppressor of anti-tumor immunity and suggest larotrectinib might be repurposed for immune sensitization. Moreover, by enlisting low-affinity T cells, anti-NGF reduces acquired resistance to immune checkpoint blockade and prevents melanoma recurrence.


Assuntos
Melanoma , Receptor de Fator de Crescimento Neural , Humanos , Receptor de Fator de Crescimento Neural/genética , Receptor de Fator de Crescimento Neural/metabolismo , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Tropomiosina , Melanoma/terapia , Receptor trkA/genética , Receptor trkA/metabolismo , Citoproteção , Inibidores de Checkpoint Imunológico , Células T de Memória , Terapia de Imunossupressão , Imunoterapia , Receptores de Antígenos de Linfócitos T
3.
Mol Cell ; 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37657444

RESUMO

N6-methyladenosine (m6A) RNA modification plays important roles in the governance of gene expression and is temporally regulated in different cell states. In contrast to global m6A profiling in bulk sequencing, single-cell technologies for analyzing m6A heterogeneity are not extensively established. Here, we developed single-nucleus m6A-CUT&Tag (sn-m6A-CT) for simultaneous profiling of m6A methylomes and transcriptomes within a single nucleus using mouse embryonic stem cells (mESCs). m6A-CT is capable of enriching m6A-marked RNA molecules in situ, without isolating RNAs from cells. We adapted m6A-CT to the droplet-based single-cell omics platform and demonstrated high-throughput performance in analyzing nuclei isolated from thousands of cells from various cell types. We show that sn-m6A-CT profiling is sufficient to determine cell identity and allows the generation of cell-type-specific m6A methylome landscapes from heterogeneous populations. These indicate that sn-m6A-CT provides additional dimensions to multimodal datasets and insights into epitranscriptomic landscape in defining cell fate identity and states.

4.
Genome Res ; 33(5): 750-762, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37308294

RESUMO

For most biological and medical applications of single-cell transcriptomics, an integrative study of multiple heterogeneous single-cell RNA sequencing (scRNA-seq) data sets is crucial. However, present approaches are unable to integrate diverse data sets from various biological conditions effectively because of the confounding effects of biological and technical differences. We introduce single-cell integration (scInt), an integration method based on accurate, robust cell-cell similarity construction and unified contrastive biological variation learning from multiple scRNA-seq data sets. scInt provides a flexible and effective approach to transfer knowledge from the already integrated reference to the query. We show that scInt outperforms 10 other cutting-edge approaches using both simulated and real data sets, particularly in the case of complex experimental designs. Application of scInt to mouse developing tracheal epithelial data shows its ability to integrate development trajectories from different developmental stages. Furthermore, scInt successfully identifies functionally distinct condition-specific cell subpopulations in single-cell heterogeneous samples from a variety of biological conditions.


Assuntos
Análise de Célula Única , Análise da Expressão Gênica de Célula Única , Animais , Camundongos , Análise de Célula Única/métodos , Perfilação da Expressão Gênica/métodos , Sequenciamento do Exoma , Análise de Sequência de RNA/métodos
5.
Nucleic Acids Res ; 52(9): e46, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647069

RESUMO

SifiNet is a robust and accurate computational pipeline for identifying distinct gene sets, extracting and annotating cellular subpopulations, and elucidating intrinsic relationships among these subpopulations. Uniquely, SifiNet bypasses the cell clustering stage, commonly integrated into other cellular annotation pipelines, thereby circumventing potential inaccuracies in clustering that may compromise subsequent analyses. Consequently, SifiNet has demonstrated superior performance in multiple experimental datasets compared with other state-of-the-art methods. SifiNet can analyze both single-cell RNA and ATAC sequencing data, thereby rendering comprehensive multi-omic cellular profiles. It is conveniently available as an open-source R package.


Assuntos
Análise de Célula Única , Software , Análise de Célula Única/métodos , Humanos , Anotação de Sequência Molecular , Algoritmos , Biologia Computacional/métodos , Análise de Sequência de RNA/métodos , Perfilação da Expressão Gênica/métodos , Sequenciamento de Cromatina por Imunoprecipitação/métodos , Análise por Conglomerados
6.
J Virol ; 98(4): e0184423, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38436247

RESUMO

Porcine Mx1 is a type of interferon-induced GTPase that inhibits the replication of certain RNA viruses. However, the antiviral effects and the underlying mechanism of porcine Mx1 for porcine reproductive and respiratory syndrome virus (PRRSV) remain unknown. In this study, we demonstrated that porcine Mx1 could significantly inhibit PRRSV replication in MARC-145 cells. By Mx1 segment analysis, it was indicated that the GTPase domain (68-341aa) was the functional area to inhibit PRRSV replication and that Mx1 interacted with the PRRSV-N protein through the GTPase domain (68-341aa) in the cytoplasm. Amino acid residues K295 and K299 in the G domain of Mx1 were the key sites for Mx1-N interaction while mutant proteins Mx1(K295A) and Mx1(K299A) still partially inhibited PRRSV replication. Furthermore, we found that the GTPase activity of Mx1 was dominant for Mx1 to inhibit PRRSV replication but was not essential for Mx1-N interaction. Finally, mechanistic studies demonstrated that the GTPase activity of Mx1 played a dominant role in inhibiting the N-Nsp9 interaction and that the interaction between Mx1 and N partially inhibited the N-Nsp9 interaction. We propose that the complete anti-PRRSV mechanism of porcine Mx1 contains a two-step process: Mx1 binds to the PRRSV-N protein and subsequently disrupts the N-Nsp9 interaction by a process requiring the GTPase activity of Mx1. Taken together, the results of our experiments describe for the first time a novel mechanism by which porcine Mx1 evolves to inhibit PRRSV replication. IMPORTANCE: Mx1 protein is a key mediator of the interferon-induced antiviral response against a wide range of viruses. How porcine Mx1 affects the replication of porcine reproductive and respiratory syndrome virus (PRRSV) and its biological function has not been studied. Here, we show that Mx1 protein inhibits PRRSV replication by interfering with N-Nsp9 interaction. Furthermore, the GTPase activity of porcine Mx1 plays a dominant role and the Mx1-N interaction plays an assistant role in this interference process. This study uncovers a novel mechanism evolved by porcine Mx1 to exert anti-PRRSV activities.


Assuntos
Proteínas de Resistência a Myxovirus , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Proteínas não Estruturais Virais , Replicação Viral , Animais , Linhagem Celular , Interferons/imunologia , Interferons/metabolismo , Mutação , Proteínas de Resistência a Myxovirus/química , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Síndrome Respiratória e Reprodutiva Suína/enzimologia , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/crescimento & desenvolvimento , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Ligação Proteica , Suínos/virologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
7.
Immunity ; 44(3): 568-581, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26921109

RESUMO

Upon antigen engagement, augmented cytosolic reactive oxygen species (ROS) are needed to achieve optimal T cell receptor (TCR) signaling. However, uncontrolled ROS production is a prominent cause of necrosis, which elicits hyper-inflammation and tissue damage. Hence, it is critical to program activated T cells to achieve ROS equilibrium. Here, we determined that miR-23a is indispensable for effector CD4(+) T cell expansion, particularly by providing early protection from excessive necrosis. Mechanistically, miR-23a targeted PPIF, gatekeeper of the mitochondria permeability transition pore, thereby restricting ROS flux and maintaining mitochondrial integrity. Upon acute Listeria monocytogenes infection, deleting miR-23a in T cells resulted in excessive inflammation, massive liver damage, and a marked mortality increase, which highlights the essential role of miR-23a in maintaining immune homeostasis.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Listeria monocytogenes/imunologia , Listeriose/imunologia , Fígado/patologia , MicroRNAs/metabolismo , Mitocôndrias/metabolismo , Animais , Células Cultivadas , Peptidil-Prolil Isomerase F , Ciclofilinas/metabolismo , Homeostase , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Necrose , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/genética
8.
Immunity ; 44(2): 422-37, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26885862

RESUMO

Dendritic cells (DCs) orchestrate complex membrane trafficking through an interconnected transportation network linked together by Rab GTPases. Through a tandem affinity purification strategy and mass spectrometry, we depicted an interactomic landscape of major members of the mammalian Rab GTPase family. When complemented with imaging tools, this proteomic analysis provided a global view of intracellular membrane organization. Driven by this analysis, we investigated dynamic changes to the Rab32 subnetwork in DCs induced by L. monocytogenes infection and uncovered an essential role of this subnetwork in controlling the intracellular proliferation of L. monocytogenes. Mechanistically, Rab32 formed a persistent complex with two interacting proteins, PHB and PHB2, to encompass bacteria both during early phagosome formation and after L. monocytogenes escaped the original containment vacuole. Collectively, we have provided a functional compartmentalization overview and an organizational framework of intracellular Rab-mediated vesicle trafficking that can serve as a resource for future investigations.


Assuntos
Células Dendríticas/imunologia , Listeria monocytogenes/imunologia , Listeriose/imunologia , Complexos Multiproteicos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Aciltransferases/metabolismo , Animais , Anti-Infecciosos/uso terapêutico , Linhagem Celular , Biologia Computacional , Contenção de Riscos Biológicos , Células Dendríticas/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/tratamento farmacológico , Camundongos , Proibitinas , Transporte Proteico , Proteínas Repressoras/metabolismo , Vacúolos/metabolismo
9.
Mol Med ; 30(1): 65, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773376

RESUMO

OBJECTIVE: Catalpol (CAT) has various pharmacological activities and plays a protective role in cerebral ischemia. It has been reported that CAT played a protective role in cerebral ischemia by upregulaing NRF1 expression. Bioinformatics analysis reveals that NRF1 can be used as a transcription factor to bind to the histone acetyltransferase KAT2A. However, the role of KAT2A in cerebral ischemia remains to be studied. Therefore, we aimed to investigate the role of CAT in cerebral ischemia and its related mechanism. METHODS: In vitro, a cell model of oxygen and glucose deprivation/reperfusion (OGD/R) was constructed, followed by evaluation of neuronal injury and the expression of METTL3, Beclin-1, NRF1, and KAT2A. In vivo, a MCAO rat model was prepared by means of focal cerebral ischemia, followed by assessment of neurological deficit and brain injury in MCAO rats. Neuronal autophagy was evaluated by observation of autophagosomes in neurons or brain tissues by TEM and detection of the expression of LC3 and p62. RESULTS: In vivo, CAT reduced the neurological function deficit and infarct volume, inhibited neuronal apoptosis in the cerebral cortex, and significantly improved neuronal injury and excessive autophagy in MCAO rats. In vitro, CAT restored OGD/R-inhibited cell viability, inhibited cell apoptosis, LDH release, and neuronal autophagy. Mechanistically, CAT upregulated NRF1, NRF1 activated METTL3 via KAT2A transcription, and METTL3 inhibited Beclin-1 via m6A modification. CONCLUSION: CAT activated the NRF1/KAT2A/METTL3 axis and downregulated Beclin-1 expression, thus relieving neuronal injury and excessive autophagy after cerebral ischemia.


Assuntos
Autofagia , Proteína Beclina-1 , Isquemia Encefálica , Glucosídeos Iridoides , Neurônios , Animais , Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Proteína Beclina-1/genética , Ratos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/tratamento farmacológico , Masculino , Glucosídeos Iridoides/farmacologia , Glucosídeos Iridoides/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Modelos Animais de Doenças , Apoptose/efeitos dos fármacos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Adenosina/análogos & derivados
10.
Small ; : e2403310, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773872

RESUMO

Understanding the structure-activity correlation is an important prerequisite for the rational design of high-efficiency electrocatalysts at the atomic level. However, the effect of coordination environment on electrocatalytic oxygen evolution reaction (OER) remains enigmatic. In this work, the regulation of proton transfer involved in water oxidation by coordination engineering based on Co3(PO4)2 and CoHPO4 is reported. The HPO4 2- anion has intermediate pKa value between Co(II)-H2O and Co(III)-H2O to be served as an appealing proton-coupled electron transfer (PCET) induction group. From theoretical calculations, the pH-dependent OER properties, deuterium kinetic isotope effects, operando electrochemical impedance spectroscopy (EIS) and Raman studies, the CoHPO4 catalyst beneficially reduces the energy barrier of proton hopping and modulates the formation energy of high-valent Co species, thereby enhancing OER activity. This work demonstrates a promising strategy that involves tuning the local coordination environment to optimize PCET steps and electrocatalytic activities for electrochemical applications. In addition, the designed system offers a motif to understand the structure-efficiency relationship from those amino-acid residue with proton buffer ability in natural photosynthesis.

11.
Nat Immunol ; 13(7): 674-80, 2012 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-22660579

RESUMO

The binding of T cell antigen receptors (TCRs) to specific complexes of peptide and major histocompatibility complex (pMHC) is typically of very low affinity, which necessitates the use of multimeric pMHC complexes to label T lymphocytes stably. We report here the development of pMHC complexes able to be crosslinked by ultraviolet irradiation; even as monomers, these efficiently and specifically stained cognate T cells. We also used this reagent to probe T cell activation and found that a covalently bound pMHC was more stimulatory than an agonist pMHC on lipid bilayers. This finding suggested that serial engagement of TCRs is dispensable for activation when a substantial fraction of TCRs are stably engaged. Finally, pMHC-bound TCRs were 'preferentially' transported into the central supramolecular activation cluster after activation, which suggested that ligand engagement enabled linkage of the TCR and its associated CD3 signaling molecules to the cytoskeleton.


Assuntos
Reagentes de Ligações Cruzadas/química , Complexo Principal de Histocompatibilidade/imunologia , Receptores de Antígenos de Linfócitos T/química , Linfócitos T/química , Animais , Complexo CD3/química , Complexo CD3/imunologia , Células Cultivadas , Corantes/química , Citoesqueleto/química , Citoesqueleto/imunologia , Ativação Linfocitária , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia
12.
Reprod Biol Endocrinol ; 22(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167101

RESUMO

BACKGROUND: The coronavirus disease (COVID-19) pandemic has seriously impacted the mental and sexual health of the general population. Patients dealing with infertility constitute a unique subset within society, susceptible to heightened sensitivity amid pressures and crises. However, to the best of our knowledge, the impact of the different stages of the COVID-19 pandemic on the mental and sexual health of patients with infertility has not been investigated. Therefore, this study aimed to investigate the mental and sexual health of patients with infertility during different stages of the COVID-19 pandemic (during the lockdown, when controls were fully liberalized, and during the post-pandemic era). METHODS: This prospective before-and-after study was conducted between April and May 2022 (during the lockdown), December and January 2023 (when controls were fully liberalized), and May and August 2023 (during the post-pandemic era). This study explored the sexual and mental health of women with infertility during the three stages of the COVID-19 pandemic using standardized mental health and sexual function questionnaires. The Chi-square test was used to compare categorical data, and the ANOVA test was used to compare numerical data. RESULTS: Patients had the highest 7-item Generalized Anxiety Disorder Scale (GAD-7) and 9-item Patient Health Questionnaire (PHQ-9) scores and the highest rates of anxiety and depression during the immediate full-release phase. During the complete liberalization phase, patients had the lowest Female Sexual Function Index (FSFI) scores and the highest incidence of sexual dysfunction. CONCLUSION: This study is the first one to report the repercussions of COVID-19 on the mental and sexual well-being of individuals experiencing infertility across various phases of the pandemic. Upon the complete lifting of control measures, close to 99% of participants exhibited varying degrees of anxiety and depression. Our research underscores that individuals with infertility faced elevated levels of anxiety, depression, and sexual dysfunction during the phase of full liberalization of COVID-19 control measures, in stark contrast to the periods of lockdown and the post-pandemic era.


Assuntos
COVID-19 , Infertilidade , Saúde Sexual , Humanos , Feminino , Pandemias , Estudos Prospectivos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Infertilidade/epidemiologia
13.
Chem Rec ; 24(1): e202300145, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37358343

RESUMO

The fast growth of electrochemical energy storage (EES) systems necessitates using innovative, high-performance electrode materials. Among the various EES devices, rechargeable batteries (RBs) with potential features like high energy density and extensive lifetime are well suited to meet rapidly increasing energy demands. Layered transition metal dichalcogenides (TMDs), typical two dimensional (2D) nanomaterial, are considered auspicious materials for RBs because of their layered structures and large specific surface areas (SSA) that benefit quick ion transportation. This review summarizes and highlights recent advances in TMDs with improved performance for various RBs. Through novel engineering and functionalization used for high-performance RBs, we briefly discuss the properties, characterizations, and electrochemistry phenomena of TMDs. We summarised that engineering with multiple techniques, like nanocomposites used for TMDs receives special attention. In conclusion, the recent issues and promising upcoming research openings for developing TMDs-based electrodes for RBs are discussed.

14.
Inorg Chem ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905324

RESUMO

The potential application of stimuli-responsive hybrid copper halides in information storage and switch devices has generated significant interest. However, their transformation mechanism needs to be further studied deeply. Herein, two zero-dimensional (0D) organic-inorganic hybrids, namely, (TBA)CuBr2 (1) with linear [CuBr2]- units and (TBA)2Cu4Br6 (2) with [Cu4Br6]2- clusters (TBA+ = (C4H9)4N+), are synthesized using simple solvent evaporation approaches. Interestingly, upon exposure to distinct protic solvents, such as methanol, ethanol, ethylene glycol, or hot water, 1 undergoes a transformation into 2 with varying degrees of transition, accompanied by a change in luminescence color from cyan to orange (or mixed color) under high-energy emission (e.g., 254 nm) excitation. Hot water can trigger 1 to completely transform into 2 because of its large contact angle difference in the solvents. Furthermore, 2 can be converted back to 1 through a simple solid-state mechanochemical reaction. Additionally, the structure of 2 remains unchanged even after immersion in 80 °C H2O for 168 h due to the dense organic framework. This study provides valuable insights for exploring reversible structural transformation materials in the 0D metal halide system.

15.
Environ Sci Technol ; 58(9): 4450-4458, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38386650

RESUMO

Calcium salt precipitation is an effective solution to wastewater fluoride pollution. The purity and precipitation efficiency of calcium fluoride is critical for its removal and recovery. This study aimed to reveal the role of coexisting sulfates in the precipitation of calcium fluoride. A low sulfate concentration promoted calcium fluoride precipitation. The size of calcium fluoride-aggregated particle clusters increased from 750 to 2000 nm when the molar ratio of sulfate to fluoride was increased from 0 to 3:100. Sulfate doped in the calcium fluoride crystals neutralized the positive charge of the calcium fluoride. Online atomic force microscopy measurements showed that sulfate reduced the repulsive force between calcium fluoride crystals and increased the adhesion force from 1.62 to 2.46 nN, promoting the agglomeration of calcium fluoride crystals. Sulfate improved the precipitation efficiency of calcium fluoride by promoting agglomeration; however, the purity of calcium fluoride was reduced by doping. Sulfate reduced the induction time of calcium fluoride crystallization and improved the nucleation rate of calcium fluoride. Sulfate should be retained to improve the precipitation of calcium fluoride and to avoid its loss from the effluents. However, it is necessary to separate sulfate from fluoride to obtain high-purity calcium fluoride. Therefore, sulfate concentration regulation in high-fluoride wastewater is key to achieving the efficient removal and recovery of fluoride ions.


Assuntos
Fluoreto de Cálcio , Fluoretos , Fluoretos/química , Águas Residuárias , Sulfatos/química , Poluição Ambiental , Cálcio
16.
Anal Bioanal Chem ; 416(13): 3139-3148, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38632131

RESUMO

The rapid discrimination of bacteria is currently an emerging trend in the fields of food safety, medical detection, and environmental observation. Traditional methods often require lengthy culturing processes, specialized analytical equipment, and bacterial recognition receptors. In response to this need, we have developed a paper-based fluorescence sensor array platform for identifying different bacteria. The sensor array is based on three unique carbon quantum dots (CQDs) as sensing units, each modified with a different antibiotic (polymyxin B, ampicillin, and gentamicin). These antibiotic-modified CQDs can aggregate on the bacterial surface, triggering aggregation-induced fluorescence quenching. The sensor array exhibits varying fluorescent responses to different bacterial species. To achieve low-cost and portable detection, CQDs were formulated into fluorescent ink and used with an inkjet printer to manufacture paper-based sensor arrays. A smartphone was used to collect the responses generated by the bacteria and platform. Diverse machine learning algorithms were utilized to discriminate bacterial types. Our findings showcase the platform's remarkable capability to differentiate among five bacterial strains, within a detection range spanning from 1.0 × 103 CFU/mL to 1.0 × 107 CFU/mL. Its practicality is further validated through the accurate identification of blind bacterial samples. With its cost-effectiveness, ease of fabrication, and high degree of integration, this platform holds significant promise for on-site detection of diverse bacteria.


Assuntos
Bactérias , Carbono , Aprendizado de Máquina , Papel , Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Bactérias/isolamento & purificação , Fluorescência , Espectrometria de Fluorescência/métodos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Antibacterianos/análise , Antibacterianos/farmacologia , Algoritmos
17.
BMC Cardiovasc Disord ; 24(1): 145, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443792

RESUMO

BACKGROUND: The SelectSecure™ 3830 lead is an innovative, lumenless, and thin active fixed lead with a nonretractable screw-in tip and a diameter of 4.1 Fr, making it the thinnest pacing lead available. Its high anti-extrusion properties and durability have shown favorable outcomes in cardiac pacing, especially in pediatric patients. The superfine design and easy implantation of the lead have rendered it a preferred choice in children, particularly in cases of congenital heart disease. CASE PRESENTATION: This case series presents two infant patients who underwent transvenous endocardial pacing using the SelectSecure™ 3830 lead, along with a comprehensive literature review on the topic. The study followed the patients for 5 years and 3 years, respectively, and observed stable pacing parameters, indicating a positive therapeutic outcome and safety. This article discusses the optimal age and body shape for transvenous lead implantation in infants and highlights the advantages and disadvantages of endocardial and epicardial pacing approaches. Although endocardial pacing offers several benefits such as minimal trauma, short hospital stay, and longer battery life, it may not be suitable for intracardiac shunts, and venous occlusion remains a concern. On the other hand, epicardial pacing may be considered for children with challenging endocardial access but comes with higher risk of lead failure and coronary artery compression. This study emphasizes the importance of careful follow-up in pediatric patients with pacing, as lead failure can occur in young patients owing to growth and development, leading to syncope and battery depletion. The article also underscores the significance of selecting the appropriate pacing location to minimize the impact of cardiac function, with right ventricular septal pacing emerging as a preferable option. CONCLUSIONS: The SelectSecure™ 3830 lead presents a promising solution for transvenous endocardial pacing in pediatric patients with high degree atrioventricular block and bradycardia, ensuring safe and effective pacing as they grow and develop.


Assuntos
Bloqueio Atrioventricular , Coração , Lactente , Humanos , Criança , Bradicardia , Vasos Coronários , Fontes de Energia Elétrica
18.
J Infect Chemother ; 30(6): 571-578, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38036028

RESUMO

INTRODUCTION: The prevalence and infection of the Zika virus (ZIKV) have recently posed a major threat to global public health security. However, there is currently a lack of specific vaccines and effective antiviral drugs for ZIKV infection. METHODS: Theaflavins TF1 and TF2 were selected by evaluating the anti-Zika virus activity of four kinds of theaflavins in vitro. Subsequently, in vivo, we investigated the effects of TF1 and TF2 on weight, survival, tissue viral load, and cytokines in ZIKV-infected mice. RESULTS: We compared the anti-ZIKV activity of four theaflavins (TFs) in cells and found that TF1 and TF2b significantly inhibited the replication of ZIKV/Z16006 toxic strain in BHK and Vero cells by inhibiting the replication and release of ZIKV, while no similar effects were observed for TF2a and TF3. In vivo assay, we only found that TF2b improved the survival rate of infected mice. In tissues of ZIKV-infected mice, the viral load was higher in spleen and blood, followed by liver, epididymis, and testis, the lowest in muscle. Additionally, TF2b treatment significantly reduced the expression of cytokines (IL-6, IL-1ß, TNF-α) and chemokines (CCL2, CCL5, CXCL10) induced by ZIKV infection. CONCLUSIONS: These findings suggest that TF2b has a potent antiviral effect and can be used as a potential candidate for the treatment of ZIKV infection.

19.
Chem Biodivers ; : e202401089, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740553

RESUMO

Croton sublyratus (Euphorbiaceae) is a traditional medicinal plant used by the Thai populace to treat helminthic infections and dermatologic conditions. In present study, eight new labdane-type diterpenoids, crotonoids A-H (1-8) and one known analogue (9) were isolated from the aerial parts of C. sublyratus. Compounds 6 and 7 belong to the rare class of 14,15-dinor-labdane diterpenoids. Compound 8 exhibited a rare 14,15,17-trinor-labdane skeleton. The structures of all these diterpenoids were elucidated by spectroscopic data analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Compound 9 exhibited moderate anti-inflammatory activity via the inhibition of NO production in lipopolysaccharide-induced RAW 264.7 cells.

20.
J Clin Ultrasound ; 52(2): 208-218, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38108620

RESUMO

PURPOSE: Using visible human, MRI and ultrasound images, we aim to provide an anatomical basis for the identification and diagnosis of pelvic floor structure and disease by ultrasound imaging. METHODS: One Chinese visible human (CVH) image, one American visible human image, 9 MRI images of normal volunteers, and 40 ultrasound images of normal volunteers or pelvic organ prolapse patients were used. Pelvic organs, pelvic floor muscles, and the connective tissue in CVH, VHP, MRI, and ultrasound images were selected for comparative study. RESULTS: We successfully identified the boundary of the anal sphincter complex, including the subcutaneous, superficial, and deep parts of the external anal sphincter, conjoined longitudinal muscles and internal anal sphincter; the levator ani muscle (LAM), including the internal and external parts of the pubovisceral muscle and the superficial and deep parts of the puborectal muscle; the urethral sphincter complex, including the urethral sphincter proper and the urethral compressor; and the perineal body, the rectoperineal muscle and superficial transverse perineal muscle. CONCLUSIONS: We successfully recognized and studied the location, subdivisions, 2D morphology and spatial relationships of the LAM, anal sphincter complex, urethral sphincter complex and perineal body in ultrasound images, thereby helping sonologists or clinicians accurately identify pelvic floor muscles and supporting structures in ultrasound images.


Assuntos
Canal Anal , Diafragma da Pelve , Humanos , Feminino , Diafragma da Pelve/diagnóstico por imagem , Diafragma da Pelve/anatomia & histologia , Diafragma da Pelve/fisiologia , Canal Anal/diagnóstico por imagem , Músculo Esquelético , Ultrassonografia , Imageamento por Ressonância Magnética
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