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1.
Cell ; 181(6): 1423-1433.e11, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32416069

RESUMO

Many COVID-19 patients infected by SARS-CoV-2 virus develop pneumonia (called novel coronavirus pneumonia, NCP) and rapidly progress to respiratory failure. However, rapid diagnosis and identification of high-risk patients for early intervention are challenging. Using a large computed tomography (CT) database from 3,777 patients, we developed an AI system that can diagnose NCP and differentiate it from other common pneumonia and normal controls. The AI system can assist radiologists and physicians in performing a quick diagnosis especially when the health system is overloaded. Significantly, our AI system identified important clinical markers that correlated with the NCP lesion properties. Together with the clinical data, our AI system was able to provide accurate clinical prognosis that can aid clinicians to consider appropriate early clinical management and allocate resources appropriately. We have made this AI system available globally to assist the clinicians to combat COVID-19.


Assuntos
Inteligência Artificial , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Tomografia Computadorizada por Raios X , COVID-19 , China , Estudos de Coortes , Infecções por Coronavirus/patologia , Infecções por Coronavirus/terapia , Conjuntos de Dados como Assunto , Humanos , Pulmão/patologia , Modelos Biológicos , Pandemias , Projetos Piloto , Pneumonia Viral/patologia , Pneumonia Viral/terapia , Prognóstico , Radiologistas , Insuficiência Respiratória/diagnóstico
3.
Nature ; 608(7922): 413-420, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922515

RESUMO

High cholesterol is a major risk factor for cardiovascular disease1. Currently, no drug lowers cholesterol through directly promoting cholesterol excretion. Human genetic studies have identified that the loss-of-function Asialoglycoprotein receptor 1 (ASGR1) variants associate with low cholesterol and a reduced risk of cardiovascular disease2. ASGR1 is exclusively expressed in liver and mediates internalization and lysosomal degradation of blood asialoglycoproteins3. The mechanism by which ASGR1 affects cholesterol metabolism is unknown. Here, we find that Asgr1 deficiency decreases lipid levels in serum and liver by stabilizing LXRα. LXRα upregulates ABCA1 and ABCG5/G8, which promotes cholesterol transport to high-density lipoprotein and excretion to bile and faeces4, respectively. ASGR1 deficiency blocks endocytosis and lysosomal degradation of glycoproteins, reduces amino-acid levels in lysosomes, and thereby inhibits mTORC1 and activates AMPK. On one hand, AMPK increases LXRα by decreasing its ubiquitin ligases BRCA1/BARD1. On the other hand, AMPK suppresses SREBP1 that controls lipogenesis. Anti-ASGR1 neutralizing antibody lowers lipid levels by increasing cholesterol excretion, and shows synergistic beneficial effects with atorvastatin or ezetimibe, two widely used hypocholesterolaemic drugs. In summary, this study demonstrates that targeting ASGR1 upregulates LXRα, ABCA1 and ABCG5/G8, inhibits SREBP1 and lipogenesis, and therefore promotes cholesterol excretion and decreases lipid levels.


Assuntos
Receptor de Asialoglicoproteína , Colesterol , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Receptor de Asialoglicoproteína/antagonistas & inibidores , Receptor de Asialoglicoproteína/deficiência , Receptor de Asialoglicoproteína/genética , Receptor de Asialoglicoproteína/metabolismo , Assialoglicoproteínas/metabolismo , Atorvastatina/farmacologia , Proteína BRCA1 , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Colesterol/metabolismo , Sinergismo Farmacológico , Endocitose , Ezetimiba/farmacologia , Humanos , Lipídeos/análise , Lipídeos/sangue , Fígado/metabolismo , Receptores X do Fígado/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1 , Ubiquitina-Proteína Ligases/metabolismo
4.
Genome Res ; 34(2): 326-340, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428994

RESUMO

Pacific Biosciences (PacBio) HiFi sequencing technology generates long reads (>10 kbp) with very high accuracy (<0.01% sequencing error). Although several de novo assembly tools are available for HiFi reads, there are no comprehensive studies on the evaluation of these assemblers. We evaluated the performance of 11 de novo HiFi assemblers on (1) real data for three eukaryotic genomes; (2) 34 synthetic data sets with different ploidy, sequencing coverage levels, heterozygosity rates, and sequencing error rates; (3) one real metagenomic data set; and (4) five synthetic metagenomic data sets with different composition abundance and heterozygosity rates. The 11 assemblers were evaluated using quality assessment tool (QUAST) and benchmarking universal single-copy ortholog (BUSCO). We also used several additional criteria, namely, completion rate, single-copy completion rate, duplicated completion rate, average proportion of largest category, average distance difference, quality value, run-time, and memory utilization. Results show that hifiasm and hifiasm-meta should be the first choice for assembling eukaryotic genomes and metagenomes with HiFi data. We performed a comprehensive benchmarking study of commonly used assemblers on complex eukaryotic genomes and metagenomes. Our study will help the research community to choose the most appropriate assembler for their data and identify possible improvements in assembly algorithms.


Assuntos
Metagenoma , Software , Análise de Sequência de DNA/métodos , Algoritmos , Metagenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos
5.
Nat Immunol ; 16(5): 505-16, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25751747

RESUMO

A cytosolic role for the histone methyltransferase Ezh2 in regulating lymphocyte activation has been suggested, but the molecular mechanisms underpinning this extranuclear function have remained unclear. Here we found that Ezh2 regulated the integrin signaling and adhesion dynamics of neutrophils and dendritic cells (DCs). Ezh2 deficiency impaired the integrin-dependent transendothelial migration of innate leukocytes and restricted disease progression in an animal model of multiple sclerosis. Direct methylation of talin, a key regulatory molecule in cell migration, by Ezh2 disrupted the binding of talin to F-actin and thereby promoted the turnover of adhesion structures. This regulatory effect was abolished by targeted disruption of the interactions of Ezh2 with the cytoskeletal-reorganization effector Vav1. Our studies reveal an unforeseen extranuclear function for Ezh2 in regulating adhesion dynamics, with implications for leukocyte migration, immune responses and potentially pathogenic processes.


Assuntos
Núcleo Celular/metabolismo , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Esclerose Múltipla/imunologia , Neutrófilos/imunologia , Complexo Repressor Polycomb 2/metabolismo , Talina/metabolismo , Actinas/metabolismo , Animais , Adesão Celular/genética , Movimento Celular , Células Cultivadas , Modelos Animais de Doenças , Proteína Potenciadora do Homólogo 2 de Zeste , Humanos , Ativação Linfocitária/genética , Metilação , Camundongos , Camundongos Knockout , Complexo Repressor Polycomb 2/genética , Ligação Proteica/genética , Proteínas Proto-Oncogênicas c-vav/metabolismo , Talina/genética , Migração Transendotelial e Transepitelial/genética
6.
Plant Cell ; 35(9): 3325-3344, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37401663

RESUMO

Stress granules (SGs) are highly conserved cytoplasmic condensates that assemble in response to stress and contribute to maintaining protein homeostasis. These membraneless organelles are dynamic, disassembling once the stress is no longer present. Persistence of SGs due to mutations or chronic stress has been often related to age-dependent protein-misfolding diseases in animals. Here, we find that the metacaspase MC1 is dynamically recruited into SGs upon proteotoxic stress in Arabidopsis (Arabidopsis thaliana). Two predicted disordered regions, the prodomain and the 360 loop, mediate MC1 recruitment to and release from SGs. Importantly, we show that MC1 has the capacity to clear toxic protein aggregates in vivo and in vitro, acting as a disaggregase. Finally, we demonstrate that overexpressing MC1 delays senescence and this phenotype is dependent on the presence of the 360 loop and an intact catalytic domain. Together, our data indicate that MC1 regulates senescence through its recruitment into SGs and this function could potentially be linked to its remarkable protein aggregate-clearing activity.


Assuntos
Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Agregados Proteicos , Grânulos de Estresse , Grânulos Citoplasmáticos/metabolismo , Estresse Fisiológico
7.
Proc Natl Acad Sci U S A ; 120(45): e2313134120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903263

RESUMO

Plants and animals that thrive in arid regions utilize the diurnal changes in environmental temperature and humidity to optimize their water budget by combining water-harvesting mechanisms and morphophysiological traits. The Athel tamarisk (Tamarix aphylla) is a halophytic desert shrub that survives in arid, hypersaline conditions by excreting concentrated solutions of ions as droplets on its surface that crystallize into salt crystals and fall off the branches. Here, we describe the crystallization on the surface of the plant and explore the effects of external conditions such as diurnal changes in humidity and temperature. The salt mixtures contain at least ten common minerals, with NaCl and CaSO4·2H2O being the major products, SiO2 and CaCO3 main sand contaminants, and Li2SO4, CaSO4, KCl, K2Ca(SO4)2·H2O, CaMg(CO3)2 and AlNaSi3O8 present in smaller amounts. In natural conditions, the hanging or sitting droplets remain firmly attached to the surface, with an average adhesion force of 275 ± 3.5 µN measured for pure water. Rather than using morphological features of the surface, the droplets adhere by chemical interactions, predominantly by hydrogen bonding. Increasing ion concentration slightly increases the contact angle on the hydrophobic cuticle, thereby lowering surface wettability. Small amounts of lithium sulfate and possibly other hygroscopic salts result in strong hygroscopicity and propensity for deliquescence of the salt mixture overnight. Within a broader context, this natural mechanism for humidity harvesting that uses environmentally benign salts as moisture adsorbents could provide a bioinspired approach that complements the currently available water collection or cloud-seeding technologies.

8.
J Virol ; : e0041323, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864728

RESUMO

Porcine epidemic diarrhea virus (PEDV) is a type A coronavirus that causes severe watery diarrhea in piglets, resulting in severe economic losses worldwide. Therefore, new approaches to control PEDV infection are essential for a robust and sustainable pig industry. We screened 314 small-molecule drug libraries provided by Selleck and found that four drugs had obviously inhibitory effects on PEDV in Vero cells. PA-824, which had the highest SI index and the most reliable clinical safety, was selected for in vivo experiments. Animal attack tests showed that PA-824 effectively alleviated the clinical signs, intestinal pathological changes, and inflammatory responses in lactating piglets after PEDV infection. To further investigate the antiviral mechanism of PA-824, we measured the inhibitory effect of PA-824 on PEDV proliferation in a dose-dependent manner. By exploring the effect of PA-824 on the PEDV life cycle, we found that PA-824 acted directly on viral particles and hindered the adsorption, internalization, and replication phases of the virus, followed by molecular docking analysis to predict the interaction between PA-824 and PEDV non-structural proteins. Finally, we found that PA-824 could inhibit the apoptotic signaling pathway by suppressing PEDV-induced p53 activation. These results suggest that PA-824 could be protective against PEDV infection in piglets and could be developed as a drug or a feed additive to prevent and control PEDV diseases.IMPORTANCEPEDV is a highly contagious enteric coronavirus that widely spread worldwide, causing serious economic losses. There is no drug or vaccine to effectively control PEDV. In this study, we found that PA-824, a compound of mycobacteria causing pulmonary diseases, inhibited PEDV proliferation in both in vitro and in vivo. We also found that PA-824 directly acted on viral particles and hindered the adsorption, internalization, and replication stages of the virus. In addition, we found that PA-824 could inhibit the apoptotic signaling pathway by inhibiting PEDV-induced p53 activation. In conclusion, it is expected to be developed as a drug or a feed additive to prevent and control PEDV diseases.

9.
J Virol ; 98(3): e0198223, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38411106

RESUMO

Continuously emerging highly pathogenic coronaviruses remain a major threat to human and animal health. Porcine deltacoronavirus (PDCoV) is a newly emerging enterotropic swine coronavirus that causes large-scale outbreaks of severe diarrhea disease in piglets. Unlike other porcine coronaviruses, PDCoV has a wide range of species tissue tropism, including primary human cells, which poses a significant risk of cross-species transmission. Nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 1 (NLRP1) has a key role in linking host innate immunity to microbes and the regulation of inflammatory pathways. We now report a role for NLRP1 in the control of PDCoV infection. Overexpression of NLRP1 remarkably suppressed PDCoV infection, whereas knockout of NLRP1 led to a significant increase in PDCoV replication. A mechanistic study revealed that NLRP1 suppressed PDCoV replication in cells by upregulating IL-11 expression, which in turn inhibited the phosphorylation of the ERK signaling pathway. Furthermore, the ERK phosphorylation inhibitor U0126 effectively hindered PDCoV replication in pigs. Together, our results demonstrated that NLRP1 exerted an anti-PDCoV effect by IL-11-mediated inhibition of the phosphorylation of the ERK signaling pathway, providing a novel antiviral signal axis of NLRP1-IL-11-ERK. This study expands our understanding of the regulatory network of NLRP1 in the host defense against virus infection and provides a new insight into the treatment of coronaviruses and the development of corresponding drugs.IMPORTANCECoronavirus, which mainly infects gastrointestinal and respiratory epithelial cells in vivo, poses a huge threat to both humans and animals. Although porcine deltacoronavirus (PDCoV) is known to primarily cause fatal diarrhea in piglets, reports detected in plasma samples from Haitian children emphasize the potential risk of animal-to-human spillover. Finding effective therapeutics against coronaviruses is crucial for controlling viral infection. Nucleotide-binding oligomerization-like receptor (NLR) family pyrin domain-containing 1 (NLRP1), a key regulatory factor in the innate immune system, is highly expressed in epithelial cells and associated with the pathogenesis of viruses. We demonstrate here that NLRP1 inhibits the infection of the intestinal coronavirus PDCoV through IL-11-mediated phosphorylation inhibition of the ERK signaling pathway. Furthermore, the ERK phosphorylation inhibitor can control the infection of PDCoV in pigs. Our study emphasizes the importance of NLRP1 as an immune regulatory factor and may open up new avenues for the treatment of coronavirus infection.


Assuntos
Infecções por Coronavirus , Deltacoronavirus , Doenças dos Suínos , Animais , Criança , Humanos , Diarreia , Haiti , Interleucina-11/metabolismo , Proteínas NLR/metabolismo , Nucleotídeos/metabolismo , Fosforilação , Transdução de Sinais , Suínos , Zoonoses/metabolismo
10.
Blood ; 142(5): 421-433, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37146250

RESUMO

Although BCL2 mutations are reported as later occurring events leading to venetoclax resistance, many other mechanisms of progression have been reported though remain poorly understood. Here, we analyze longitudinal tumor samples from 11 patients with disease progression while receiving venetoclax to characterize the clonal evolution of resistance. All patients tested showed increased in vitro resistance to venetoclax at the posttreatment time point. We found the previously described acquired BCL2-G101V mutation in only 4 of 11 patients, with 2 patients showing a very low variant allele fraction (0.03%-4.68%). Whole-exome sequencing revealed acquired loss(8p) in 4 of 11 patients, of which 2 patients also had gain (1q21.2-21.3) in the same cells affecting the MCL1 gene. In vitro experiments showed that CLL cells from the 4 patients with loss(8p) were more resistant to venetoclax than cells from those without it, with the cells from 2 patients also carrying gain (1q21.2-21.3) showing increased sensitivity to MCL1 inhibition. Progression samples with gain (1q21.2-21.3) were more susceptible to the combination of MCL1 inhibitor and venetoclax. Differential gene expression analysis comparing bulk RNA sequencing data from pretreatment and progression time points of all patients showed upregulation of proliferation, B-cell receptor (BCR), and NF-κB gene sets including MAPK genes. Cells from progression time points demonstrated upregulation of surface immunoglobulin M and higher pERK levels compared with those from the preprogression time point, suggesting an upregulation of BCR signaling that activates the MAPK pathway. Overall, our data suggest several mechanisms of acquired resistance to venetoclax in CLL that could pave the way for rationally designed combination treatments for patients with venetoclax-resistant CLL.


Assuntos
Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Humanos , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Sequenciamento do Exoma , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2
11.
Exp Cell Res ; 439(2): 114097, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38796135

RESUMO

Leucine-rich α2-glycoprotein-1 (LRG1) is overexpressed in various cancers, including non-small cell lung cancer (NSCLC), but its role in NSCLC cell metastasis is not well understood. In this study, NSCLC cell exosomes were analyzed using different techniques, and the impact of exosomal LRG1 on NSCLC cell behavior was investigated through various assays both in vitro and in vivo. The study revealed that LRG1, found abundantly in NSCLC cells and exosomes, enhanced cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). Exosomal LRG1 was shown to promote NSCLC cell metastasis in animal models. Additionally, the interaction between LRG1 and fibronectin 1 (FN1) in the cytoplasm was identified. It was observed that FN1 could counteract the effects of LRG1 knockdown on cell regulation induced by exosomes derived from NSCLC cells. Overall, the findings suggest that targeting exosomal LRG1 or FN1 may hold therapeutic potential for treating NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Movimento Celular , Proliferação de Células , Exossomos , Fibronectinas , Glicoproteínas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Exossomos/metabolismo , Exossomos/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Proliferação de Células/genética , Fibronectinas/metabolismo , Fibronectinas/genética , Animais , Glicoproteínas/metabolismo , Glicoproteínas/genética , Movimento Celular/genética , Camundongos , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Camundongos Nus , Metástase Neoplásica , Camundongos Endogâmicos BALB C , Regulação Neoplásica da Expressão Gênica , Células A549
12.
Mol Cell Proteomics ; 22(6): 100559, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37105363

RESUMO

The 2nd CASMS conference was held virtually through Gather. Town platform from October 17 to 21, 2022, with a total of 363 registrants including an outstanding and diverse group of scientists at the forefront of their research fields from both academia and industry worldwide, especially in the United States and China. The conference offered a 5-day agenda with an exciting scientific program consisting of two plenary lectures, 14 parallel symposia, and 4 special sessions in which a total of 97 invited speakers presented technological innovations and their applications in proteomics & biological mass spectrometry and metabo-lipidomics & pharmaceutical mass spectrometry. In addition, 18 invited speakers/panelists presented at 3 research-focused and 2 career development workshops. Moreover, 144 posters, 54 lightning talks, 5 sponsored workshops, and 14 exhibitions were presented, from which 20 posters and 8 lightning talks received presentation awards. Furthermore, the conference featured 1 MCP lectureship and 5 young investigator awardees for the first time to highlight outstanding mid-career and early-career rising stars in mass spectrometry from our society. The conference provided a unique scientific platform for young scientists (i.e., graduate students, postdocs and junior faculty/investigators) to present their research, meet with prominent scientists, and learn about career development and job opportunities (http://casms.org).


Assuntos
Espectrometria de Massas , Sociedades Científicas , Humanos , China , Preparações Farmacêuticas , Proteômica , Estados Unidos
13.
Proc Natl Acad Sci U S A ; 119(41): e2211538119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191233

RESUMO

Efficient molecular selection is a prerequisite for generating molecular tools used in diagnosis, pathology, vaccinology, and therapeutics. Selection efficiency is thermodynamically highly dependent on the dissociation equilibrium that can be reached in a single round. Extreme shifting of equilibrium towards dissociation favors the retention of high-affinity ligands over those with lower affinity, thus improving the selection efficiency. We propose to synergize dual effects by deterministic lateral-displacement microfluidics, including the collision-based force effect and the two-dimensional (2D) separation-based concentration effect, to greatly shift the equilibrium. Compared with previous approaches, this system can remove more low- or moderate-affinity ligands and maintain most high-affinity ligands, thereby improving affinity discrimination in selection. This strategy is demonstrated on phage display in both experiment and simulation, and two peptides against tumor markers ephrin type-A receptor 2 (EphA2) and CD71 were obtained with high affinity and specificity within a single round of selection, which offers a promising direction for discovery of robust binding ligands for a wide range of biomedical applications.


Assuntos
Microfluídica , Peptídeos , Biomarcadores Tumorais , Efrinas , Ligantes , Peptídeos/química
14.
Proc Natl Acad Sci U S A ; 119(48): e2206829119, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36409915

RESUMO

Retinal ganglion cells (RGCs) are heterogeneous projection neurons that convey distinct visual features from the retina to brain. Here, we present a high-throughput in vivo RGC activity assay in response to light stimulation using noninvasive Ca2+ imaging of thousands of RGCs simultaneously in living mice. Population and single-cell analyses of longitudinal RGC Ca2+ imaging reveal distinct functional responses of RGCs and unprecedented individual RGC activity conversions during traumatic and glaucomatous degeneration. This study establishes a foundation for future in vivo RGC function classifications and longitudinal activity evaluations using more advanced imaging techniques and visual stimuli under normal, disease, and neural repair conditions. These analyses can be performed at both the population and single-cell levels using temporal and spatial information, which will be invaluable for understanding RGC pathophysiology and identifying functional biomarkers for diverse optic neuropathies.


Assuntos
Glaucoma , Células Ganglionares da Retina , Animais , Camundongos , Diagnóstico por Imagem , Retina , Glaucoma/diagnóstico por imagem , Encéfalo
15.
Differentiation ; 135: 100744, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38128465

RESUMO

Differentiation of human umbilical cord mesenchymal stem cells (Uc-MSCs) into islet-like clusters which are capable of synthesizing and secreting insulin can potentially serve as donors for islet transplantation in the patient deficiency in islet ß cell function both in type 1 or type 2 diabetic patients. Therefore, we developed an easy and higher efficacy approach by trypsinazing the Uc-MSCs and followed culture in differentiation medium to induce of Uc-MSCs differentiation into islet-like clusters, and the potential mechanism that in the early stage of differentiation was also investigated by using RNA-sequencing and bioinformatics. Results show that induction efficacy was reached to 98% and TGF-ß signaling pathway may play critical role in the early stage differentiation, it was further confirmed that the retardant effect of differentiation progress either in cell morphology or in islet specific genes expression can be observed upon blocking the activation of TGF-ß signaling pathway using specific inhibitor of LY2109761 (TßRI/II kinase inhibitor). Our current study, for the first time, development a protocol for differentiation of Uc-MSCs into islet-like clusters, and revealed the importance of TGF-ß signaling pathway in the early stage of differentiation of Uc-MSCs into islet-like clusters. Our study will provide alternative approach for clinical treatment of either type I or type II diabtes mellitus with dysfunctional pancreatic islets.


Assuntos
Células Secretoras de Insulina , Células-Tronco Mesenquimais , Humanos , Insulina , Tripsina/metabolismo , Diferenciação Celular/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais , Cordão Umbilical
16.
Eur Heart J ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865332

RESUMO

BACKGROUND AND AIMS: Extracellular vesicles (EVs) secreted by cardiosphere-derived cells exert immunomodulatory effects through the transmission of small non-coding RNAs. METHODS: The mechanism and role of yREX3, a small Y RNA abundant in EVs in myocardial injury, was investigated. RESULTS: yREX3 attenuates cardiac ischaemic injury by selective DNA methylation. Synthetic yREX3 encapsulated in lipid nanoparticles triggers broad transcriptomic changes in macrophages, localizes to the nucleus, and mediates epigenetic silencing of protein interacting with C kinase-1 (Pick1) through methylation of upstream CpG sites. Moreover, yREX3 interacts with polypyrimidine tract binding protein 3 (PTBP3) to methylate the Pick1 gene locus in a DNA methyltransferase-dependent manner. Suppression of Pick1 in macrophages potentiates Smad3 signalling and enhances efferocytosis, minimizing heart necrosis in rats with myocardial infarction. Adoptive transfer of Pick1-deficient macrophages recapitulates the cardioprotective effects of yREX3 in vivo. CONCLUSIONS: These findings highlight the role of a small Y RNA mined from EVs with a novel gene-methylating mechanism.

17.
Chem Soc Rev ; 53(8): 3687-3713, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38411997

RESUMO

The cornerstones of the advancement of flexible optoelectronics are the design, preparation, and utilization of novel materials with favorable mechanical and advanced optoelectronic properties. Molecular crystalline materials have emerged as a class of underexplored yet promising materials due to the reduced grain boundaries and defects anticipated to provide enhanced photoelectric characteristics. An inherent drawback that has precluded wider implementation of molecular crystals thus far, however, has been their brittleness, which renders them incapable of ensuring mechanical compliance required for even simple elastic or plastic deformation of the device. It is perplexing that despite a plethora of reports that have in the meantime become available underpinning the flexibility of molecular crystals, the "discovery" of elastically or plastically deformable crystals remains limited to cases of serendipitous and laborious trial-and-error approaches, a situation that calls for a systematic and thorough assessment of these properties and their correlation with the structure. This review provides a comprehensive and concise overview of the current understanding of the origins of crystal flexibility, the working mechanisms of deformations such as plastic and elastic bending behaviors, and insights into the examples of flexible molecular crystals, specifically concerning photoelectronic changes that occur in deformed crystals. We hope this summary will provide a reference for future experimental and computational efforts with flexible molecular crystals aimed towards improving their mechanical behavior and optoelectronic properties, ultimately intending to advance the flexible optoelectronic technology.

18.
Nano Lett ; 24(2): 703-707, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38175934

RESUMO

Gold-dithiol molecular junctions have been studied both experimentally and theoretically. However, the nature of the gold-thiolate bond as it relates to the solvent has seldom been investigated. It is known that solvents can impact the electronic structure of single-molecule junctions, but the correlation between the solvent and dithiol-linked single-molecule junction conductance is not well understood. We study molecular junctions formed with thiol-terminated phenylenes from both 1-chloronaphthalene and 1-bromonaphthalene solutions. We find that the most probable conductance and the distribution of conductances are both affected by the solvent. First-principles calculations show that junction conductance depends on the binding configurations (adatom, atop, and bridge) of the thiolate on the Au surface, as has been shown previously. More importantly, we find that brominated solvents can restrict the binding of thiols to specific Au sites. This mechanism offers new insight into the effects of the solvent environment on covalent bonding in molecular junctions.

19.
J Infect Dis ; 229(6): 1648-1657, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38297970

RESUMO

BACKGROUND: Staphylococcus aureus is the most common cause of life-threatening endovascular infections, including infective endocarditis (IE). These infections, especially when caused by methicillin-resistant strains (MRSA), feature limited therapeutic options and high morbidity and mortality rates. METHODS: Herein, we investigated the role of the purine biosynthesis repressor, PurR, in virulence factor expression and vancomycin (VAN) treatment outcomes in experimental IE due to MRSA. RESULTS: The PurR-mediated repression of purine biosynthesis was confirmed by enhanced purF expression and production of an intermediate purine metabolite in purR mutant strain. In addition, enhanced expression of the transcriptional regulators, sigB and sarA, and their key downstream virulence genes (eg, fnbA, and hla) was demonstrated in the purR mutant in vitro and within infected cardiac vegetations. Furthermore, purR deficiency enhanced fnbA/fnbB transcription, translating to increased fibronectin adhesion versus the wild type and purR-complemented strains. Notably, the purR mutant was refractory to significant reduction in target tissues MRSA burden following VAN treatment in the IE model. CONCLUSIONS: These findings suggest that the purine biosynthetic pathway intersects the coordination of virulence factor expression and in vivo persistence during VAN treatment, and may represent an avenue for novel antimicrobial development targeting MRSA.


Assuntos
Antibacterianos , Proteínas de Bactérias , Endocardite Bacteriana , Staphylococcus aureus Resistente à Meticilina , Purinas , Proteínas Repressoras , Infecções Estafilocócicas , Vancomicina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Animais , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Purinas/biossíntese , Antibacterianos/farmacologia , Vancomicina/farmacologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/tratamento farmacológico , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Camundongos , Regulação Bacteriana da Expressão Gênica , Modelos Animais de Doenças , Testes de Sensibilidade Microbiana , Humanos
20.
BMC Genomics ; 25(1): 333, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570739

RESUMO

BACKGROUND: The closed poultry houses integrated with a longitudinal water curtain cooling system (LWCCS) are widely used in modern poultry production. This study showed the variations in environmental conditions in closed houses integrated with a longitudinal water curtain cooling system. We evaluated the influence of different environmental conditions on duck growth performance and the transcriptome changes of immune organs, including the bursa of Fabricius and the spleen. RESULT: This study investigated the slaughter indicators and immune organ transcriptomes of 52-day-old Cherry Valley ducks by analyzing the LWCC at different locations (water curtain end, middle position, and fan cooling end). The results showed that the cooling effect of the LWCCS was more evident from 10:00 a.m. -14:00. And from the water curtain end to the fan cooling end, the hourly average temperature differently decreased by 0.310℃, 0.450℃, 0.480℃, 0.520℃, and 0.410℃, respectively (P < 0.05). The daily and hourly average relative humidity decreased from the water curtain end to the fan cooling end, dropping by 7.500% and 8.200%, respectively (P < 0.01). We also observed differences in production performance, such as dressing weight, half-eviscerated weight, skin fat rate, and percentage of abdominal fat (P < 0.01), which may have been caused by environmental conditions. RNA-sequencing (RNA-seq) revealed 211 and 279 differentially expressed genes (DEGs) in the ducks' bursa of Fabricius and spleen compared between the water curtain end and fan cooling end, respectively. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the two organs showed the DEGs were mainly enriched in cytokine-cytokine receptor interaction, integral component of membrane, Retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) signaling pathway, etc. Our results implied that full-closed poultry houses integrated with LWCCS could potentially alter micro-environments (water curtain vs. fan cooling), resulting in ducks experiencing various stressful situations that eventually affect their immunity and production performance. CONCLUSION: In this study, our results indicated that uneven distributions of longitudinal environmental factors caused by LWCCS would affect the dressed weight, breast muscle weight, skin fat rate, and other product performance. Moreover, the expression of immune-related genes in the spleen and bursa of ducks could be affected by the LWCCS. This provides a new reference to optimize the use of LWCCS in conjunction with close duck houses in practical production.


Assuntos
Patos , Transcriptoma , Animais , Patos/genética , Patos/metabolismo , Transdução de Sinais , Citocinas/genética , Perfilação da Expressão Gênica
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