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1.
Plant Physiol Biochem ; 212: 108738, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38761544

RESUMEN

In the realm of ornamental horticulture, crape myrtle (Lagerstroemia indica) stands out for its aesthetic appeal, attributed largely to its vibrant flowers and distinctive branching architecture. This study embarked on a comprehensive exploration of the gibberellin oxidase (GAox) gene family in crape myrtle, illuminating its pivotal role in regulating GA levels, a key determinant of plant developmental processes. We identified and characterized 36 LiGAox genes, subdivided into GA2ox, GA3ox, GA20ox, and GAox-like subgroups, through genomic analyses. These genes' evolutionary trajectories were delineated, revealing significant gene expansions attributed to segmental duplication events. Functional analyses highlighted the divergent expression patterns of LiGAox genes across different crape myrtle varieties, associating them with variations in flower color and branching architecture. Enzymatic activity assays on selected LiGA2ox enzymes exhibited pronounced GA2 oxidase activity, suggesting a potential regulatory role in GA biosynthesis. Our findings offered a novel insight into the molecular underpinnings of GA-mediated growth and development in L. indica, providing a foundational framework for future genetic enhancements aimed at optimizing ornamental traits.

2.
Int Immunopharmacol ; 132: 111972, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38569429

RESUMEN

The potential of cytotoxic CD4+ T cells and tissue resident memory T cells (Trm) in achieving adult leukemia remission have been highlighted [1,2]. We hypothesized that CXCR6 could serve as a marker for cytotoxic CD4+ Trm cells in the bone marrow (BM) of pediatric B-ALL patients. Flow cytometry (FCM) and published single cell RNA sequencing (scRNA-seq) datasets were employed to characterize CXCR6+CD4+ T cells in the BM and peripheral blood (PB) of pediatric B-ALL patients and healthy donors. FCM, scRNA-seq and co-culture were utilized to explore the cytotoxicity of CXCR6+CD4+ T cells in vitro based on in vitro induction of CXCR6+CD4+ T cells using tumor antigens and peripheral blood mononuclear cells (PBMCs). The ssGSEA based on the cell markers identified according to the in vivo scRNA-seq data, the TARGET-ALL-P2 datasets, and integrated machine learning algorithm were employed to figure out the key cells with prognostic values, followed by simulation of adoptive cell transfer therapy (ACT). Integrated machine learning identified the high-risk cells for disease free survival, and overall survival, while simulation of ACT therapy using CXCR6+CD4+T cells indicated that CXCR6+CD4+ T cells could remodel the bone marrow microenvironments towards anti-tumor. Based on the expression of genes involved in formation of resident memory T cells, CXCR6 is not a marker of resident memory CD4+T cells but defines therapeutic subtypes of CD4+ cytotoxic T cell lineage for pediatric B-ALL.


Asunto(s)
Inmunoterapia Adoptiva , Receptores CXCR6 , Humanos , Inmunoterapia Adoptiva/métodos , Niño , Receptores CXCR6/genética , Receptores CXCR6/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/inmunología , Linfocitos T Citotóxicos/inmunología , Masculino , Preescolar , Femenino , Linfocitos T CD4-Positivos/inmunología , Linaje de la Célula
3.
Int J Biol Macromol ; 266(Pt 1): 131095, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537859

RESUMEN

Gibberellin oxidases (GAoxs) identified from many species play indispensable roles in GA biosynthesis and GA signal transduction. However, there has been limited research conducted on the GAox family of Salix matsudana, a tetraploid ornamental tree species. Here, 54 GAox genes were identified from S. matsudana and renamed as SmGA20ox1-22, SmGA2ox1-24, SmGA3ox1-6, and SmGAox-like1/2. Gene structure and conserved motif analysis showed that SmGA3ox members possess the 1 intron and other SmGAoxs contain 2-3 introns, and motif 1/2/7 universally present in all SmGAoxs. A total of 69 gene pairs were identified from SmGAox family members, and the Ka/Ks values indicated the SmGAoxs experience the purifying selection. The intra species collinearity analysis implied S. matsudana, S. purpurea, and Populus trichocarpa have the close genetic relationship. The GO analysis suggested SmGAoxs are dominantly involved in GA metabolic process, ion binding, and oxidoreductase activity. RNA-sequencing demonstrated that some SmGAoxs may play an essential role in salt and submergence stresses. In addition, the SmGA20ox13/21 displayed the dominant vitality of GA20 oxidase, but the SmGA20ox13/21 still possessed low activities of GA2 and GA3 oxidases. This study can contribute to reveal the regulatory mechanism of salt and submergence tolerance in willow.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Giberelinas , Oxigenasas de Función Mixta , Filogenia , Salix , Perfilación de la Expresión Génica , Giberelinas/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Salix/genética
4.
Int Immunopharmacol ; 132: 111945, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38555816

RESUMEN

BACKGROUND: Emodin, a natural anthraquinone derivative isolated from the roots of Rheum officinale Baill, has many pharmacological effects including anti-inflammatory, antioxidant, antiviral, antibacterial and anti-cancer. However, little is known about the effect of emodin on acute radiation proctitis (ARP). The present study was conducted to determine its effects and elucidate its mechanisms involving AKT/MAPK/NF-κB/VEGF pathways in ARP mice. METHODS: Total 60 C57BL/6 mice were divided randomly into control group, ARP group, AKT inhibitor MK-2206 group, and different doses of emodin groups. ARP mice were induced by 27 Gy of 6 MV X-ray pelvic local irradiation. MK-2206 was given orally for 2 weeks on alternate days. Emodin was administered daily by oral gavage for 2 weeks. Subsequently, all mice were sacrificed on day 15. The rectal tissues were obtained for further tests. The general signs score and the pathological grade were used to evaluate the severity of ARP. The expression of NF-κB, VEGF and AQP1 were determined by immunohistochemistry and western blot. The expression of p-AKT, p-ERK, p-JNK, p-p38, Bcl-2 and Bax were assessed using western blot. RESULTS: The worse general signs and damaged tissue structure of ARP mice were profoundly ameliorated by emodin. The expression of p-AKT, p-ERK, NF-κB, VEGF and AQP1 were significantly increased, resulting in the inflammation-induced angiogenesis in ARP mice. However, the expression of p-JNK and p-p38 were decreased, leading to the reduction of apoptosis in ARP mice. Excitedly, emodin reversed these changes, not only inhibited inflammation-induced angiogenesis, but also promoted apoptosis. Notably, the effects of emodin were similar to that of AKT inhibitor MK-2206, suggesting the involvement of AKT signaling in the effect of emodin. CONCLUSION: These results suggest that emodin attenuates ARP in mice, and the underlying mechanism might involve inhibition of the AKT/ERK/NF-κB/VEGF pathways and the induction of apoptosis mediated by JNK and p38.


Asunto(s)
Emodina , Ratones Endogámicos C57BL , FN-kappa B , Proctitis , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular , Animales , Emodina/farmacología , Emodina/uso terapéutico , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proctitis/tratamiento farmacológico , Proctitis/etiología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ratones , Transducción de Señal/efectos de los fármacos , Traumatismos por Radiación/tratamiento farmacológico , Traumatismos por Radiación/patología , Masculino , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Compuestos Heterocíclicos con 3 Anillos/farmacología , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Traumatismos Experimentales por Radiación/patología , Traumatismos Experimentales por Radiación/metabolismo , Recto/patología , Recto/efectos de los fármacos
5.
BMC Plant Biol ; 24(1): 78, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38287275

RESUMEN

BACKGROUND: Annexin (ANN) is calcium (Ca2+)-dependent and phospholipid binding protein family, which is involved in plant growth and development and response to various stresses. However, little known about ANN genes were identified from crape myrtle, an ornamental horticultural plant widely cultivated in the world. RESULTS: Here, 9 LiANN genes were identified from Lagerstroemia indica, and their characterizations and functions were investigated in L. indica for the first time. The LiANN genes were divided into 2 subfamilies. The gene structure, chromosomal location, and collinearity relationship were also explored. In addition, the GO annotation analysis of these LiANNs indicated that they are enriched in molecular functions, cellular components, and biological processes. Moreover, transcription factors (TFs) prediction analysis revealed that bHLH, MYB, NAC, and other TFs can interact with the LiANN promoters. Interestingly, the LiANN2/4/6-9 were demonstrated to play critical roles in the branching architecture of crape myrtle. Furthermore, the LiANN2/6/8/9 were differentially expressed under salt treatment, and a series of TFs regulating LiANN2/6/8/9 expression were predicted to play essential roles in salt resistance. CONCLUSIONS: These results shed light on profile and function of the LiANN gene family, and lay a foundation for further studies of the LiANN genes.


Asunto(s)
Lagerstroemia , Myrtus , Lagerstroemia/genética , Anexinas/genética , Factores de Transcripción/genética , Estrés Salino/genética , Regulación de la Expresión Génica de las Plantas , Filogenia
6.
Int Immunopharmacol ; 128: 111544, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266445

RESUMEN

The dysregulation of B cell maturation and putrescine metabolism has been implicated in various diseases. However, the causal relationship between them and the underlying mechanisms remain unclear. In this study, we investigated the impact of exogenous putrescine on B cell differentiation in the intestinal microenvironment. Our results demonstrated that administration of exogenous putrescine significantly impaired the proportion of germinal center B (GC B) cells in Peyer's patches (PPs) and lamina propria. Through integration of bulk RNA sequencing and single-cell RNA sequencing (scRNA-seq), we identified putrescine-mediated changes in gene drivers, including those involved in the B cell receptor (BCR) signaling pathway and fatty acid oxidation. Furthermore, putrescine drinking disrupted T-B cell interactions and increased reactive oxygen species (ROS) production in B cells. In vitro activation of B cells confirmed the direct suppression of putrescine on GC B cells differentiation and ROS production. Additionally, we explored the Pearson correlations between putrescine biosynthesis activity and B cell infiltration in pan-cancers, revealing negative correlations in colon adenocarcinoma, stomach adenocarcinoma, and lung adenocarcinoma, but positive correlations in liver hepatocellular carcinoma, and breast invasive carcinoma. Our findings provided novel insights into the suppressive effects of elevated enteric putrescine on intestinal B cells differentiation and highlighted the complex and distinctive immunoregulatory role of putrescine in different microenvironments. These findings expand our understanding of the role of polyamines in B cell immunometabolism and related diseases.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Humanos , Putrescina/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Adenocarcinoma/metabolismo , Ganglios Linfáticos Agregados/metabolismo , Neoplasias del Colon/metabolismo , Centro Germinal , Diferenciación Celular , Microambiente Tumoral
7.
Adv Sci (Weinh) ; : e2304301, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039435

RESUMEN

Drug studies targeting neuronal ion channels are crucial to understand neuronal function and develop therapies for neurological diseases. The traditional method to study neuronal ion-channel activities heavily relies on the whole-cell patch clamp as the industry standard. However, this technique is both technically challenging and labour-intensive, while involving the complexity of keeping cells alive with low throughput. Therefore, the shortcomings are limiting the efficiency of ion-channel-related neuroscience research and drug testing. Here, this work reports a new system of integrating neuron membranes with organic microelectrode arrays (OMEAs) for ion-channel-related drug studies. This work demonstrates that the supported lipid bilayers (SLBs) derived from both neuron-like (neuroblastoma) cells and primary neurons are integrated with OMEAs for the first time. The increased expression of voltage-gated calcium (CaV) ion channels on differentiated SH-SY5Y SLBs  compared to non-differentiated ones is sensed electrically. Also, dose-response of the CaV ion-channel blocking effect on primary cortical neuronal SLBs from rats is monitored. The dose range causing ion channel blocking is comparable to literature. This system overcomes the major challenges from traditional methods (e.g., patch clamp) and showcases an easy-to-test, rapid, ultra-sensitive, cell-free, and high-throughput platform to monitor dose-dependent ion-channel blocking effects on native neuronal membranes.

8.
Int J Antimicrob Agents ; 62(4): 106925, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37451649

RESUMEN

Klebsiella pneumoniae is one of the most common opportunistic pathogens causing hospital- and community-acquired infections. Antibiotic resistance in K. pneumoniae has emerged as a major clinical and public health threat. Persisters are specific antibiotic-tolerant bacterial cells. Studies on the mechanism underlying their formation mechanism and growth status are scarce. Therefore, it is urgent to explore the key genes and signalling pathways involved in the formation and recovery process of K. pneumoniae persisters to enhance the understanding and develop relevant treatment strategies. In this study, we treated K. pneumoniae with a lethal concentration of levofloxacin. It resulted in a distinct plateau of surviving levofloxacin-tolerant persisters. Subsequently, we obtained bacterial samples at five different time points during the formation and recovery of K. pneumoniae persisters to perform transcriptome analysis. ptsH gene was observed to be upregulated during the formation of persisters, and down-regulated during the recovery of the persisters. Further, we used CRISPR-Cas9 to construct ΔptsH, the ptsH-knockout K. pneumoniae strain, and to investigate the effect of ptsH on the persister formation. We observed that ptsH can promote the formation of persisters, reduce accumulation of reactive oxygen species, and enhance antioxidant capacity by reducing cyclic adenosine monophosphate (cAMP) levels. To the best of our knowledge, this is the first study to report that ptsH plays a vital role in forming K. pneumoniae persisters. This study provided important insights to further explore the mechanism underlying the formation of K. pneumoniae persisters and provided a potential target for treating infection with K. pneumoniae persisters.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Levofloxacino/farmacología , Antibacterianos/farmacología , Adenosina Monofosfato , Fosfotransferasas/farmacología , Infecciones por Klebsiella/microbiología
9.
Mater Horiz ; 10(9): 3589-3600, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37318042

RESUMEN

Three-dimensional in vitro stem cell models have enabled a fundamental understanding of cues that direct stem cell fate. While sophisticated 3D tissues can be generated, technology that can accurately monitor these complex models in a high-throughput and non-invasive manner is not well adapted. Here we show the development of 3D bioelectronic devices based on the electroactive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)-(PEDOT:PSS) and their use for non-invasive, electrical monitoring of stem cell growth. We show that the electrical, mechanical and wetting properties as well as the pore size/architecture of 3D PEDOT:PSS scaffolds can be fine-tuned simply by changing the processing crosslinker additive. We present a comprehensive characterization of both 2D PEDOT:PSS thin films of controlled thicknesses, and 3D porous PEDOT:PSS structures made by the freeze-drying technique. By slicing the bulky scaffolds we generate homogeneous, porous 250 µm thick PEDOT:PSS slices, constituting biocompatible 3D constructs able to support stem cell cultures. These multifunctional slices are attached on indium-tin oxide substrates (ITO) with the help of an electrically active adhesion layer, enabling 3D bioelectronic devices with a characteristic and reproducible, frequency dependent impedance response. This response changes drastically when human adipose derived stem cells (hADSCs) grow within the porous PEDOT:PSS network as revealed by fluorescence microscopy. The increase of cell population within the PEDOT:PSS porous network impedes the charge flow at the interface between PEDOT:PSS and ITO, enabling the interface resistance (R1) to be used as a figure of merit to monitor the proliferation of stem cells. The non-invasive monitoring of stem cell growth allows for the subsequent differentiation 3D stem cell cultures into neuron like cells, as verified by immunofluorescence and RT-qPCR measurements. The strategy of controlling important properties of 3D PEDOT:PSS structures simply by altering processing parameters can be applied for development of a number of stem cell in vitro models as well as stem cell differentiation pathways. We believe the results presented here will advance 3D bioelectronic technology for both fundamental understanding of in vitro stem cell cultures as well as the development of personalized therapies.


Asunto(s)
Células Madre Adultas , Electricidad , Humanos , Neuronas , Diferenciación Celular , Impedancia Eléctrica
10.
ACS Biomater Sci Eng ; 9(6): 3632-3642, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37137156

RESUMEN

The use of bacteriophages, viruses that specifically infect bacteria, as antibiotics has become an area of great interest in recent years as the effectiveness of conventional antibiotics recedes. The detection of phage interactions with specific bacteria in a rapid and quantitative way is key for identifying phages of interest for novel antimicrobials. Outer membrane vesicles (OMVs) derived from Gram-negative bacteria can be used to make supported lipid bilayers (SLBs) and therefore in vitro membrane models that contain naturally occurring components of the bacterial outer membrane. In this study, we employed Escherichia coli OMV derived SLBs and use both fluorescent imaging and mechanical sensing techniques to show their interactions with T4 phage. We also integrate these bilayers with microelectrode arrays (MEAs) functionalized with the conducting polymer PEDOT:PSS and show that the pore forming interactions of the phages with the SLBs can be monitored using electrical impedance spectroscopy. To highlight our ability to detect specific phage interactions, we also generate SLBs using OMVs derived from Citrobacter rodentium, which is resistant to T4 phage infection, and identify their lack of interaction with the phage. The work presented here shows how interactions occurring between the phages and these complex SLB systems can be monitored using a range of experimental techniques. We believe this approach can be used to identify phages that work against bacterial strains of interest, as well as more generally to monitor any pore forming structure (such as defensins) interacting with bacterial outer membranes, and thus aid in the development of next generation antimicrobials.


Asunto(s)
Bacteriófagos , Membrana Dobles de Lípidos , Membrana Dobles de Lípidos/química , Escherichia coli , Antibacterianos/farmacología
11.
Adv Healthc Mater ; 12(27): e2301194, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37171457

RESUMEN

Tumor-derived extracellular vesicles (TEVs) induce the epithelial-to-mesenchymal transition (EMT) in nonmalignant cells to promote invasion and cancer metastasis, representing a novel therapeutic target in a field severely lacking in efficacious antimetastasis treatments. However, scalable technologies that allow continuous, multiparametric monitoring for identifying metastasis inhibitors are absent. Here, the development of a functional phenotypic screening platform based on organic electrochemical transistors (OECTs) for real-time, noninvasive monitoring of TEV-induced EMT and screening of antimetastatic drugs is reported. TEVs derived from the triple-negative breast cancer cell line MDA-MB-231 induce EMT in nonmalignant breast epithelial cells (MCF10A) over a nine-day period, recapitulating a model of invasive ductal carcinoma metastasis. Immunoblot analysis and immunofluorescence imaging confirm the EMT status of TEV-treated cells, while dual optical and electrical readouts of cell phenotype are obtained using OECTs. Further, heparin, a competitive inhibitor of cell surface receptors, is identified as an effective blocker of TEV-induced EMT. Together, these results demonstrate the utility of the platform for TEV-targeted drug discovery, allowing for facile modeling of the transient drug response using electrical measurements, and provide proof of concept that inhibitors of TEV function have potential as antimetastatic drug candidates.


Asunto(s)
Neoplasias de la Mama , Vesículas Extracelulares , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Detección Precoz del Cáncer , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Transición Epitelial-Mesenquimal/genética , Movimiento Celular , Melanoma Cutáneo Maligno
12.
Front Public Health ; 11: 1160294, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113168

RESUMEN

Background: Hearing loss has occurred as a critical concern for aging and health. However, it remains unknown whether nocturnal sleep and midday napping duration are associated with hearing loss in middle-aged and older adults. Methods: The study comprised 9,573 adults from China Health and Retirement Longitudinal Study, who have completed the survey for sleep characteristics and subjective functional hearing. We collected self-reported nocturnal sleep duration (<5, 5 to <6, 6 to <7, 7 to <9, ≥9 h/night) and midday napping duration (≤5, 5 to ≤30, and >30 min). The sleep information was classified into different sleep patterns. The primary outcome was self-reported hearing loss events. Multivariate Cox regression models and restricted cubic splines were used to investigate the longitudinal association of sleep characteristics with hearing loss. We applied Cox generalized additive models and bivariate exposure-response surface diagrams to visualize the effects of different sleep patterns on hearing loss. Results: We confirmed 1,073 cases of hearing loss (55.1% female) during the follow-up. After adjusting for demographic characteristics, lifestyle factors and health condition, nocturnal sleep with < 5 h was positively associated with hearing loss [hazard ratio (HR): 1.45, 95% confidence interval [CI]: 1.20, 1.75]. Individuals with napping for 5 to ≤30 min had a 20% (HR: 0.80, 95%CI: 0.63, 1.00) lower risk of hearing loss compared with those with napping ≤ 5 min. Restrictive cubic splines showed the reverse J-shaped association between nocturnal sleep and hearing loss. Moreover, we found significant joint effects of sleeping < 7 h/night and midday napping ≤ 5 min (HR: 1.27, 95% CI: 1.06, 1.52) on hearing loss. Bivariate exposure-response surface diagrams also reflected the finding that short sleep without napping existed the highest risk of hearing loss. Compared with persistently sleeping moderately (7-9 h/night), those who persistently slept < 7 h/night or shifted from < 7 h/night to moderate or > 9 h/night had higher risks of hearing loss. Conclusion: Inadequate nocturnal sleep was associated with an elevated risk of poor subjective hearing in middle-aged and older adults, while moderate napping decreased the risk of hearing loss. Keeping sleep stable within recommendation duration may be a useful strategy for preventing poor hearing loss.


Asunto(s)
Duración del Sueño , Sueño , Persona de Mediana Edad , Humanos , Femenino , Anciano , Masculino , Factores de Riesgo , Estudios Longitudinales , Estudios de Cohortes , Sueño/fisiología , Privación de Sueño , Audición , China/epidemiología
13.
Artículo en Inglés | MEDLINE | ID: mdl-37115842

RESUMEN

Real-time simulation of hyperelastic membranes like cloth still faces a lot of challenges, such as hyperplasticity modeling and contact handling. In this study, we propose projective peridynamics that uses a local-global strategy to enable fast and robust simulation of hyperelastic membranes with contact. In the global step, we propose a semi-implicit strategy to linearize the governing equation for hyperelastic materials that are modeled with peridynamics. By decomposing the first Piola-Kirchhoff stress tensor into a positive and a negative part, successive substitutions can be taken to solve the nonlinear problems. Convergence is guaranteed by further addressing the overshooting problem. Since our global step solve requires no energy summation and dot product operations over the entire problem, it fits into GPU implementation perfectly. In the local step, we further present a GPU-friendly gradient descent method to prevent interpenetration by solving an optimization problem independently. Putting the global and local solves together, experiments show that our method is robust and efficient in simulating complex models of membranes involving hyperelastic materials and contact.

14.
ACS Appl Mater Interfaces ; 15(10): 12766-12776, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36866935

RESUMEN

As the threat of antibiotic resistance increases, there is a particular focus on developing antimicrobials against pathogenic bacteria whose multidrug resistance is especially entrenched and concerning. One such target for novel antimicrobials is the ATP-binding cassette (ABC) transporter MsbA that is present in the plasma membrane of Gram-negative pathogenic bacteria where it is fundamental to the survival of these bacteria. Supported lipid bilayers (SLBs) are useful in monitoring membrane protein structure and function since they can be integrated with a variety of optical, biochemical, and electrochemical techniques. Here, we form SLBs containing Escherichia coli MsbA and use atomic force microscopy (AFM) and structured illumination microscopy (SIM) as high-resolution microscopy techniques to study the integrity of the SLBs and incorporated MsbA proteins. We then integrate these SLBs on microelectrode arrays (MEA) based on the conducting polymer poly(3,4-ethylenedioxy-thiophene) poly(styrene sulfonate) (PEDOT:PSS) using electrochemical impedance spectroscopy (EIS) to monitor ion flow through MsbA proteins in response to ATP hydrolysis. These EIS measurements can be correlated with the biochemical detection of MsbA-ATPase activity. To show the potential of this SLB approach, we observe not only the activity of wild-type MsbA but also the activity of two previously characterized mutants along with quinoline-based MsbA inhibitor G907 to show that EIS systems can detect changes in ABC transporter activity. Our work combines a multitude of techniques to thoroughly investigate MsbA in lipid bilayers as well as the effects of potential inhibitors of this protein. We envisage that this platform will facilitate the development of next-generation antimicrobials that inhibit MsbA or other essential membrane transporters in microorganisms.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Técnicas Biosensibles , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/química , Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas Bacterianas/metabolismo , Membrana Dobles de Lípidos/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Adenosina Trifosfato/metabolismo
15.
Int Immunopharmacol ; 116: 109739, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36706590

RESUMEN

Dendritic cells (DCs) play pivotal roles in immune responses. The differentiation and function of DCs are regulated by environmental metabolites. Putrescine is ubiquitous in various metabolic microenvironments and its immunoregulation has been of increasing interest. However, the mechanisms associated with its DC-induced immunoregulation remain unclear. In this study, we found putrescine promoted induction of immature bone marrow derived DCs (BMDCs), along with the increased phagocytosis and migration, and altered cytokine secretion in immature BMDCs. Transcriptomic profiles indicated significantly impaired inflammatory-related pathways, elevated oxidative phosphorylation, and decreased p-STAT3 (Tyr705) expression. Additionally, putrescine performed minor influence on the lipopolysaccharide (LPS)-induced maturation of BMDCs but significantly impaired LPS-induced DC-elicited allogeneic T-cell proliferation as well as the cytokine secretion. Furthermore, molecular docking and dynamics on the conjugation between putrescine and STAT3 revealed that putrescine could be stably bound to the hydrophilic cavity in STAT3 and performed significant influence on the Tyr705 phosphorylation. CUT&Tag analysis uncovered altered motifs, downregulated IFN-γ response, and upregulated p53 pathway in Putrescine group compared with Control group. In summary, our results demonstrated for the first time that putrescine might accelerate the differentiation of BMDCs by inhibiting the phosphorylation of STAT3 at Tyr705. Given that both DCs and putrescine have ubiquitous and distinct roles in various immune responses and pathogeneses, our findings may provide more insights into polyamine immunoregulation on DCs, as well as distinct strategies in the clinical utilization of DCs by targeting polyamines.


Asunto(s)
Lipopolisacáridos , Putrescina , Fosforilación , Putrescina/farmacología , Putrescina/metabolismo , Lipopolisacáridos/metabolismo , Médula Ósea , Simulación del Acoplamiento Molecular , Diferenciación Celular , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas , Células de la Médula Ósea/metabolismo
16.
ACS Synth Biol ; 11(12): 3921-3928, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36473701

RESUMEN

Modeling in systems and synthetic biology relies on accurate parameter estimates and predictions. Accurate model calibration relies, in turn, on data and on how well suited the available data are to a particular modeling task. Optimal experimental design (OED) techniques can be used to identify experiments and data collection procedures that will most efficiently contribute to a given modeling objective. However, implementation of OED is limited by currently available software tools that are not well suited for the diversity of nonlinear models and non-normal data commonly encountered in biological research. Moreover, existing OED tools do not make use of the state-of-the-art numerical tools, resulting in inefficient computation. Here, we present the NLoed software package and demonstrate its use with in vivo data from an optogenetic system in Escherichia coli. NLoed is an open-source Python library providing convenient access to OED methods, with particular emphasis on experimental design for systems biology research. NLoed supports a wide variety of nonlinear, multi-input/output, and dynamic models and facilitates modeling and design of experiments over a wide variety of data types. To support OED investigations, the NLoed package implements maximum likelihood fitting and diagnostic tools, providing a comprehensive modeling workflow. NLoed offers an accessible, modular, and flexible OED tool set suited to the wide variety of experimental scenarios encountered in systems biology research. We demonstrate NLoed's capabilities by applying it to experimental design for characterization of a bacterial optogenetic system.


Asunto(s)
Proyectos de Investigación , Biología de Sistemas , Biología de Sistemas/métodos , Modelos Biológicos , Programas Informáticos , Biología Sintética , Escherichia coli/genética
17.
ACS Cent Sci ; 8(9): 1238-1257, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36188342

RESUMEN

Infectious diseases continue to pose a substantial burden on global populations, requiring innovative broad-spectrum prophylactic and treatment alternatives. Here, we have designed modular synthetic polymer nanoparticles that mimic functional components of host cell membranes, yielding multivalent nanomimics that act by directly binding to varied pathogens. Nanomimic blood circulation time was prolonged by reformulating polymer-lipid hybrids. Femtomolar concentrations of the polymer nanomimics were sufficient to inhibit herpes simplex virus type 2 (HSV-2) entry into epithelial cells, while higher doses were needed against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given their observed virustatic mode of action, the nanomimics were also tested with malaria parasite blood-stage merozoites, which lose their invasive capacity after a few minutes. Efficient inhibition of merozoite invasion of red blood cells was demonstrated both in vitro and in vivo using a preclinical rodent malaria model. We envision these nanomimics forming an adaptable platform for developing pathogen entry inhibitors and as immunomodulators, wherein nanomimic-inhibited pathogens can be secondarily targeted to sites of immune recognition.

18.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35409235

RESUMEN

Identifying new disease indications for existing drugs can help facilitate drug development and reduce development cost. The previous drug-disease association prediction methods focused on data about drugs and diseases from multiple sources. However, they did not deeply integrate the neighbor topological information of drug and disease nodes from various meta-path perspectives. We propose a prediction method called NAPred to encode and integrate meta-path-level neighbor topologies, multiple kinds of drug attributes, and drug-related and disease-related similarities and associations. The multiple kinds of similarities between drugs reflect the degrees of similarity between two drugs from different perspectives. Therefore, we constructed three drug-disease heterogeneous networks according to these drug similarities, respectively. A learning framework based on fully connected neural networks and a convolutional neural network with an attention mechanism is proposed to learn information of the neighbor nodes of a pair of drug and disease nodes. The multiple neighbor sets composed of different kinds of nodes were formed respectively based on meta-paths with different semantics and different scales. We established the attention mechanisms at the neighbor-scale level and at the neighbor topology level to learn enhanced neighbor feature representations and enhanced neighbor topological representations. A convolutional-autoencoder-based module is proposed to encode the attributes of the drug-disease pair in three heterogeneous networks. Extensive experimental results indicated that NAPred outperformed several state-of-the-art methods for drug-disease association prediction, and the improved recall rates demonstrated that NAPred was able to retrieve more actual drug-disease associations from the top-ranked candidates. Case studies on five drugs further demonstrated the ability of NAPred to identify potential drug-related disease candidates.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Biología Computacional/métodos , Desarrollo de Medicamentos/métodos , Recuerdo Mental
19.
Mater Horiz ; 8(4): 1253-1263, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34821918

RESUMEN

The strategy of band convergence of multi-valley conduction bands or multi-peak valence bands has been widely used to search or improve thermoelectric materials. However, the phonon-assisted intervalley scatterings due to multiple band degeneracy are usually neglected in the thermoelectric community. In this work, we investigate the (thermo)electric properties of non-polar monolayer ß- and α-antimonene considering full mode- and momentum-resolved electron-phonon interactions. We also analyze thoroughly the selection rules on electron-phonon matrix-elements using group-theory arguments. Our calculations reveal strong intervalley scatterings between the nearly degenerate valley states in both ß- and α-antimonene, and the commonly-used deformation potential approximation neglecting the dominant intervalley scattering gives inaccurate estimations of the electron-phonon scattering and thermoelectric transport properties. By considering full electron-phonon interactions based on the rigid-band approximation, we find that, the maximum value of the thermoelectric figure of merits zT at room temperature reduces to 0.37 in ß-antimonene, by a factor of 5.7 compared to the value predicted based on the constant relaxation-time approximation method. Our work not only provides an accurate prediction of the thermoelectric performances of antimonenes, which reveals the key role of intervalley scatterings in determining the electronic part of zT, but also exhibits a computational framework for thermoelectric materials.

20.
J Phys Chem Lett ; 12(25): 5871-5878, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34143630

RESUMEN

Coherent longitudinal lattice vibrations of black phosphorus provide unique access to the out-of-plane strain coupled in-plane optical properties. In this work, polarization-resolved femtosecond transient absorption microscopy is applied to study the anisotropic coherent phonon responses. Multiorder phonon harmonics were observed with thickness dependence well explained by the linear chain model, allowing rapid optical mapping of phonon frequency distributions. More interestingly, exotic coherent phonon oscillations occourred with a π-phase jump between the armchair and zigzag polarizations, which reveals opposite signs of photoelasticity under the longitudinal strain. Specifically, compressive strain reduces the imaginary refractive index in the armchair polarization but increases the real refractive index in the zigzag polarization, as confirmed by the ab initio calculations and thin film model. These fundamental properties of black phosphorus hold potential for applications in ultrafast and polarization-sensitive photoacoustic/photoelastic modulators.

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