RESUMO
The IscB proteins, as the ancestors of Cas9 endonuclease, hold great promise due to their small size and potential for diverse genome editing. However, their activity in mammalian cells is unsatisfactory. By introducing three residual substitutions in IscB, we observed an average 7.5-fold increase in activity. Through fusing a sequence-non-specific DNA-binding protein domain, the eIscB-D variant achieved higher editing efficiency, with a maximum of 91.3%. Moreover, engineered ωRNA was generated with a 20% reduction in length and slightly increased efficiency. The engineered eIscB-D/eωRNA system showed an average 20.2-fold increase in activity compared with the original IscB. Furthermore, we successfully adapted eIscB-D for highly efficient cytosine and adenine base editing. Notably, eIscB-D is highly active in mouse cell lines and embryos, enabling the efficient generation of disease models through mRNA/ωRNA injection. Our study suggests that these miniature genome-editing tools have great potential for diverse applications.
Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Edição de Genes/métodos , Camundongos , Humanos , Embrião de Mamíferos/metabolismo , Células HEK293 , Engenharia de Proteínas/métodosRESUMO
Type III-A CRISPR-Cas surveillance complexes containing multi-subunit Csm effector, guide, and target RNAs exhibit multiple activities, including formation of cyclic-oligoadenylates (cAn) from ATP and subsequent cAn-mediated cleavage of single-strand RNA (ssRNA) by the trans-acting Csm6 RNase. Our structure-function studies have focused on Thermococcus onnurineus Csm6 to deduce mechanistic insights into how cA4 binding to the Csm6 CARF domain triggers the RNase activity of the Csm6 HEPN domain and what factors contribute to regulation of RNA cleavage activity. We demonstrate that the Csm6 CARF domain is a ring nuclease, whereby bound cA4 is stepwise cleaved initially to ApApApA>p and subsequently to ApA>p in its CARF domain-binding pocket, with such cleavage bursts using a timer mechanism to regulate the RNase activity of the Csm6 HEPN domain. In addition, we establish T. onnurineus Csm6 as an adenosine-specific RNase and identify a histidine in the cA4 CARF-binding pocket involved in autoinhibitory regulation of RNase activity.
Assuntos
Nucleotídeos de Adenina/química , Proteínas Arqueais/química , Proteínas Associadas a CRISPR/química , Sistemas CRISPR-Cas , Oligorribonucleotídeos/química , Ribonucleases/química , Thermococcus/química , Sítios de Ligação , Domínios ProteicosRESUMO
Atherosclerosis is an arterial disease process characterized by the focal subendothelial accumulation of apolipoprotein-B-containing lipoproteins, immune and vascular wall cells, and extracellular matrix. The lipoproteins acquire features of damage-associated molecular patterns and trigger first an innate immune response, dominated by monocyte-macrophages, and then an adaptive immune response. These inflammatory responses often become chronic and non-resolving and can lead to arterial damage and thrombosis-induced organ infarction. The innate immune response is regulated at various stages, from hematopoiesis to monocyte changes and macrophage activation. The adaptive immune response is regulated primarily by mechanisms that affect the balance between regulatory and effector T cells. Mechanisms related to cellular cholesterol, phenotypic plasticity, metabolism, and aging play key roles in affecting these responses. Herein, we review select topics that shed light on these processes and suggest new treatment strategies.
Assuntos
Aterosclerose/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Linfócitos T/imunologia , Imunidade Adaptativa/imunologia , Animais , Humanos , Imunidade Inata/imunologia , Lipoproteínas/imunologia , Modelos ImunológicosRESUMO
Insertion sequence (IS)-excision enhancer (IEE) promotes the excision of ISs in the genome of enterohemorrhagic Escherichia coli O157. Because IEE-dependent IS excision occurs in the presence of transposase, the process of IS transposition may be involved in IS excision; however, little is understood about the molecular mechanisms of IS excision. Our in vitro analysis revealed that IEE exhibits DNA-dependent ATPase activity, which is activated by branched DNA. IEE also catalyzes the branch migration of fork-structured DNA. These results suggest that IEE remodels branched structures of the IS transposition intermediate. Sequence analysis of recombination sites in IS-excision products suggested that microhomologous sequences near the ends of the IS are involved in IS excision. IEE promoted microhomology-mediated end joining (MMEJ), in which base pairing between 6-nucleotides complementary ends of two 3'-protruding DNAs and subsequent elongation of the paired DNA strand occurred. IS-excision frequencies were significantly decreased in cells producing IEE mutants that had lost either branch migration or MMEJ activity, which suggests that these activities of IEE are required for IS excision. Based on our results, we propose a model for IS excision triggered by IEE and transposase.
Assuntos
Reparo do DNA , Elementos de DNA Transponíveis , Elementos de DNA Transponíveis/genética , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , Transposases/genética , Transposases/metabolismoRESUMO
The NFE2L2 (NRF2) oncogene and transcription factor drives a gene expression program that promotes cancer progression, metabolic reprogramming, immune evasion, and chemoradiation resistance. Patient stratification by NRF2 activity may guide treatment decisions to improve outcome. Here, we developed a mass spectrometry-based targeted proteomics assay based on internal standard-triggered parallel reaction monitoring to quantify 69 NRF2 pathway components and targets, as well as 21 proteins of broad clinical significance in head and neck squamous cell carcinoma (HNSCC). We improved an existing internal standard-triggered parallel reaction monitoring acquisition algorithm, called SureQuant, to increase throughput, sensitivity, and precision. Testing the optimized platform on 27 lung and upper aerodigestive cancer cell models revealed 35 NRF2 responsive proteins. In formalin-fixed paraffin-embedded HNSCCs, NRF2 signaling intensity positively correlated with NRF2-activating mutations and with SOX2 protein expression. Protein markers of T-cell infiltration correlated positively with one another and with human papilloma virus infection status. CDKN2A (p16) protein expression positively correlated with the human papilloma virus oncogenic E7 protein and confirmed the presence of translationally active virus. This work establishes a clinically actionable HNSCC protein biomarker assay capable of quantifying over 600 peptides from frozen or formalin-fixed paraffin-embedded archived tissues in under 90 min.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/metabolismo , Fator 2 Relacionado a NF-E2 , Proteômica , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Biomarcadores Tumorais/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/uso terapêutico , FormaldeídoRESUMO
Recent political polarization has illustrated how individuals with opposing political views often experience ongoing events in markedly different ways. In this study, we explored the neural mechanisms underpinning this phenomenon. We conducted fMRI scanning of 34 right- and left-wing participants (45% females) watching political videos (e.g., campaign ads and political speeches) just before the elections in Israel. As expected, we observed significant differences between left- and right-wing participants in their interpretation of the videos' content. Furthermore, neuroimaging results revealed partisanship-dependent differences in activation and synchronization in higher-order regions. Surprisingly, such differences were also revealed in early sensory, motor, and somatosensory regions. We found that the political content synchronized the responses of primary visual and auditory cortices in a partisanship-dependent manner. Moreover, right-wing (and not left-wing) individuals' sensorimotor cortex was involved in processing right-wing (and not left-wing) political content. These differences were pronounced to the extent that we could predict political orientation from the early brain-response alone. Importantly, no such differences were found with respect to neutral content. Therefore, these results uncover more fundamental neural mechanisms underlying processes of political polarization.SIGNIFICANCE STATEMENT The political sphere has become highly polarized in recent years. Would it be possible to identify the neural mechanisms underpinning such processes? In our study, left- and right-wing participants were scanned in fMRI while watching political video clips just before the elections in Israel. We found that political content was potent in synchronizing the brain responses of individuals holding similar views. This was far more pronounced in individuals holding right-wing views. Moreover, partisan-dependent differences in neural responses were identified already in early sensory, somatosensory, and motor regions, and only for political content. These results suggest that individuals' political views shape their neural responses at a very basic level.
Assuntos
Córtex Auditivo , Córtex Sensório-Motor , Feminino , Humanos , Masculino , Córtex Auditivo/fisiologia , Fala/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodosRESUMO
Ischemic stroke (IS) poses a significant threat to global human health and life. In recent decades, we have witnessed unprecedented progresses against IS, including thrombolysis, thrombectomy, and a few medicines that can assist in reopening the blocked brain vessels or serve as standalone treatments for patients who are not eligible for thrombolysis/thrombectomy therapies. However, the narrow time windows of thrombolysis/thrombectomy, coupled with the risk of hemorrhagic transformation, as well as the lack of highly effective and safe medications, continue to present big challenges in the acute treatment and long-term recovery of IS. In the past 3 years, several excellent articles have reviewed pathophysiology of IS and therapeutic medicines for the treatment of IS based on the pathophysiology. Regretfully, there is no comprehensive overview to summarize all categories of anti-IS drugs/agents designed and synthesized based on molecular mechanisms of IS pathophysiology. From medicinal chemistry view of point, this article reviews a multitude of anti-IS drugs/agents, including small molecule compounds, natural products, peptides, and others, which have been developed based on the molecular mechanism of IS pathophysiology, such as excitotoxicity, oxidative/nitrosative stresses, cell death pathways, and neuroinflammation, and so forth. In addition, several emerging medicines and strategies, including nanomedicines, stem cell therapy and noncoding RNAs, which recently appeared for the treatment of IS, are shortly introduced. Finally, the perspectives on the associated challenges and future directions of anti-IS drugs/agents are briefly provided to move the field forward.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , AVC Isquêmico/etiologia , Terapia Trombolítica/efeitos adversos , Trombectomia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Resultado do TratamentoRESUMO
When confronted with injustice, individuals often intervene as third parties to restore justice by either punishing the perpetrator or helping the victim, even at their own expense. However, little is known about how individual differences in third-party intervention propensity are related to inter-individual variability in intrinsic brain connectivity patterns and how these associations vary between help and punishment intervention. To address these questions, we employed a novel behavioral paradigm in combination with resting-state fMRI and inter-subject representational similarity analysis (IS-RSA). Participants acted as third-party bystanders and needed to decide whether to maintain the status quo or intervene by either helping the disadvantaged recipient (Help condition) or punishing the proposer (Punish condition) at a specific cost. Our analyses focused on three brain networks proposed in the third-party punishment (TPP) model: the salience (e.g., dorsal anterior cingulate cortex, dACC), central executive (e.g., dorsolateral prefrontal cortex, dlPFC), and default mode (e.g., dorsomedial prefrontal cortex, dmPFC; temporoparietal junction, TPJ) networks. IS-RSA showed that individual differences in resting-state functional connectivity (rs-FC) patterns within these networks were associated with the general third-party intervention propensity. Moreover, rs-FC patterns of the right dlPFC and right TPJ were more strongly associated with individual differences in the helping propensity rather than the punishment propensity, whereas the opposite pattern was observed for the dmPFC. Post-hoc predictive modeling confirmed the predictive power of rs-FC in these regions for intervention propensity across individuals. Collectively, these findings shed light on the shared and distinct roles of key regions in TPP brain networks at rest in accounting for individual variations in justice-restoring intervention behaviors.
Assuntos
Encéfalo , Córtex Pré-Frontal , Humanos , Encéfalo/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Mapeamento Encefálico , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND & AIMS: After pediatric liver transplantation (pLT), children undergo life-long immunosuppression since reliable biomarkers for the assessment of rejection probability are scarce. In the multicenter (n = 7) prospective clinical cohort "ChilSFree" study, we aimed to characterize longitudinal dynamics of soluble and cellular immune mediators during the first year after pLT and identify early biomarkers associated with outcome. METHODS: Using a Luminex-based multiplex technique paired with flow cytometry, we characterized longitudinal dynamics of soluble immune mediators (SIMs, n = 50) and immune cells in the blood of 244 patients at eight visits over 1 year: before, and 7/14/21/28 days and 3/6/12 months after pLT. RESULTS: The unsupervised clustering of patients based on SIM profiles revealed six unique SIM signatures associated with clinical outcome. From three signatures linked to improved outcome, one was associated with 1-year-long rejection-free survival and stable graft function and was characterized by low levels of pro-inflammatory SIMs (CXCL8/9/10/12, CCL7, SCGF-ß, sICAM-1), and high levels of regenerative (SCF, TNF-ß) and pro-apoptotic (TRAIL) SIMs (all, p <0.001, fold change >100). Of note, this SIM signature appeared 2 weeks after pLT and remained stable over the entire year, pointing towards its potential as a novel early biomarker for minimizing or weaning immunosuppression. In the blood of these patients, a higher frequency of CD56bright natural killer cells (p <0.01), a known hallmark also associated with operationally tolerant pLT patients, was detected. The concordance of the model for prediction of rejection based on identified SIM signatures was 0.715, and 0.795, in combination with living-related transplantation as a covariate, respectively. CONCLUSIONS: SIM blood signatures may enable the non-invasive and early assessment of rejection risks in the first year after pLT, paving the way for improved clinical management. IMPACT AND IMPLICATIONS: ChilSFree represents the largest pediatric liver transplant (pLT) cohort with paired longitudinal data on soluble immune mediators (SIMs) and immune phenotyping in the first year after pLT. SIM signatures allow for the selection of rejection-free patients 2 weeks after pLT independently of patient diagnosis, sex, or age. The SIM signatures may enable the non-invasive and early assessment of rejection risks, paving the way for minimization or withdrawal of immunosuppression after pLT.
Assuntos
Biomarcadores , Rejeição de Enxerto , Transplante de Fígado , Humanos , Masculino , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/sangue , Rejeição de Enxerto/diagnóstico , Criança , Biomarcadores/sangue , Pré-Escolar , Estudos Prospectivos , Lactente , Adolescente , Sobrevivência de Enxerto/imunologiaRESUMO
Vancomycin heteroresistance is prone to missed detection and poses a risk of clinical treatment failure. We encountered one clinical Enterococcus faecium strain, SRR12, that carried a complete vanM gene cluster but was determined as susceptible to vancomycin using the broth microdilution method. However, distinct subcolonies appeared within the clear zone of inhibition in the E-test assay, one of which, named SRR12-v1, showed high-level resistance to vancomycin. SRR12 was confirmed as heteroresistant to vancomycin using population analysis profiling and displayed "revive" growth curves with a lengthy lag phase of over 13 hours when exposed to 2-32 mg/L vancomycin. The resistant subcolony SRR12-v1 was found to carry an identical vanM gene cluster to that of SRR12 but a significantly increased vanM copy number in the genome. Long-read whole genome sequencing revealed that a one-copy vanM gene cluster was located on a pELF1-like linear plasmid in SRR12. In comparison, tandem amplification of the vanM gene cluster jointed with IS1216E was seated on a linear plasmid in the genome of SRR12-v1. These amplifications of the vanM gene cluster were demonstrated as unstable and would decrease accompanied by fitness reversion after serial passaging for 50 generations under increasing vancomycin pressure or without antibiotic pressure but were relatively stable under constant vancomycin pressure. Further, vanM resistance in resistant variants was verified to be carried by conjugative plasmids with variable sizes using conjugation assays and S1-pulsed field gel electrophoresis blotting, suggesting the instability/flexibility of vanM cluster amplification in the genome and an increased risk of vanM resistance dissemination.
Assuntos
Antibacterianos , Enterococcus faecium , Testes de Sensibilidade Microbiana , Família Multigênica , Plasmídeos , Resistência a Vancomicina , Vancomicina , Enterococcus faecium/genética , Enterococcus faecium/efeitos dos fármacos , Plasmídeos/genética , Vancomicina/farmacologia , Resistência a Vancomicina/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Humanos , Sequenciamento Completo do GenomaRESUMO
It has been shown that an evolutionary tradeoff between vertical (host growth rate) and horizontal (plasmid conjugation) transmissions contributes to global plasmid fitness. As conjugative IncC plasmids are important for the spread of multidrug resistance (MDR), in a broad range of bacterial hosts, we investigated vertical and horizontal transmissions of two multidrug-resistant IncC plasmids according to their backbones and MDR-region rearrangements, upon plasmid entry into a new host. We observed plasmid genome deletions after conjugation in three diverse natural Escherichia coli clinical strains, varying from null to high number depending on the plasmid, all occurring in the MDR region. The plasmid burden on bacterial fitness depended more on the strain background than on the structure of the MDR region, with deletions appearing to have no impact. Besides, we observed an increase in plasmid transfer rate, from ancestral host to new clinical recipient strains, when the IncC plasmid was rearranged. Finally, using a second set of conjugation experiments, we investigated the evolutionary tradeoff of the IncC plasmid during the critical period of plasmid establishment in E. coli K-12, by correlating the transfer rates of deleted or non-deleted IncC plasmids and their costs on the recipient strain. Plasmid deletions strongly improved conjugation efficiency with no negative growth effect. Our findings indicate that the flexibility of the MDR-region of the IncC plasmids can promote their dissemination, and provide diverse opportunities to capture new resistance genes. In a broader view, they suggest that the vertical-horizontal transmission tradeoff can be manipulated by the plasmid to improve its fitness.
Assuntos
Conjugação Genética , Farmacorresistência Bacteriana Múltipla , Escherichia coli , Plasmídeos , Plasmídeos/genética , Escherichia coli/genética , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal/genética , Genoma Bacteriano/genética , Antibacterianos/farmacologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissãoRESUMO
Type I interferons (IFN-Is) are a class of proinflammatory cytokines produced in response to viruses and environmental stimulations, resulting in chronic inflammation and even carcinogenesis. However, the connection between IFN-I and p53 mutation is poorly understood. Here, we investigated IFN-I status in the context of mutant p53 (p53N236S , p53S). We observed significant cytosolic double-stranded DNA (dsDNA) derived from nuclear heterochromatin in p53S cells, along with an increased expression of IFN-stimulated genes. Further study revealed that p53S promoted cyclic GMP-AMP synthase (cGAS) and IFN-regulatory factor 9 (IRF9) expression, thus activating the IFN-I pathway. However, p53S/S mice were more susceptible to herpes simplex virus 1 infection, and the cGAS-stimulator of IFN genes (STING) pathway showed a decline trend in p53S cells in response to poly(dA:dT) accompanied with decreased IFN-ß and IFN-stimulated genes, whereas the IRF9 increased in response to IFN-ß stimulation. Our results illustrated the p53S mutation leads to low-grade IFN-I-induced inflammation via consistent low activation of the cGAS-STING-IFN-I axis, and STAT1-IRF9 pathway, therefore, impairs the protective cGAS-STING signalling and IFN-I response encountered with exogenous DNA attack. These results suggested the dual molecular mechanisms of p53S mutation in inflammation regulation. Our results could be helping in further understanding of mutant p53 function in chronic inflammation and provide information for developing new therapeutic strategies for chronic inflammatory diseases or cancer.
Assuntos
Interferon Tipo I , Proteína Supressora de Tumor p53 , Camundongos , Animais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Nucleotidiltransferases/genética , Interferon Tipo I/metabolismo , Transdução de Sinais/genética , Inflamação , Imunidade Inata/genéticaRESUMO
Previous research has suggested that certain types of the affective temperament, including depressive, cyclothymic, hyperthymic, irritable, and anxious, are subclinical manifestations and precursors of mental disorders. However, the neural mechanisms that underlie these temperaments are not fully understood. The aim of this study was to identify the brain regions associated with different affective temperaments. We collected the resting-state functional magnetic resonance imaging (fMRI) data from 211 healthy adults and evaluated their affective temperaments using the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire. We used intersubject representational similarity analysis to identify brain regions associated with each affective temperament. Brain regions associated with each affective temperament were detected. These regions included the prefrontal cortex, anterior cingulate cortex (ACC), precuneus, amygdala, thalami, hippocampus, and visual areas. The ACC, lingual gyri, and precuneus showed similar activity across several affective temperaments. The similarity in related brain regions was high among the cyclothymic, irritable, and anxious temperaments, and low between hyperthymic and the other affective temperaments. These findings may advance our understanding of the neural mechanisms underlying affective temperaments and their potential relationship to mental disorders and may have potential implications for personalized treatment strategies for mood disorders.
Assuntos
Afeto , Imageamento por Ressonância Magnética , Temperamento , Humanos , Adulto , Masculino , Feminino , Adulto Jovem , Temperamento/fisiologia , Afeto/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologiaRESUMO
The novel genus Aquibium that lacks nitrogenase was recently reclassified from the Mesorhizobium genus. The genomes of Aquibium species isolated from water were smaller and had higher GC contents than those of Mesorhizobium species. Six Mesorhizobium species lacking nitrogenase were found to exhibit low similarity in the average nucleotide identity values to the other 24 Mesorhizobium species. Therefore, they were classified as the non-N2-fixing Mesorhizobium lineage (N-ML), an evolutionary intermediate species. The results of our phylogenomic analyses and the loss of Rhizobiales-specific fur/mur indicated that Mesorhizobium species may have evolved from Aquibium species through an ecological transition. Halotolerant and alkali-resistant Aquibium and Mesorhizobium microcysteis belonging to N-ML possessed many tripartite ATP-independent periplasmic transporter and sodium/proton antiporter subunits composed of seven genes (mrpABCDEFG). These genes were not present in the N2-fixing Mesorhizobium lineage (ML), suggesting that genes acquired for adaptation to highly saline and alkaline environments were lost during the evolution of ML as the habitat changed to soil. Land-to-water habitat changes in Aquibium species, close relatives of Mesorhizobium species, could have influenced their genomic evolution by the gain and loss of genes. Our study indicated that lineage-specific evolution could have played a significant role in shaping their genome architecture and conferring their ability to thrive in different habitats.IMPORTANCEPhylogenetic analyses revealed that the Aquibium lineage (AL) and non-N2-fixing Mesorhizobium lineage (N-ML) were monophyletically grouped into distinct clusters separate from the N2-fixing Mesorhizobium lineage (ML). The N-ML, an evolutionary intermediate species having characteristics of both ancestral and descendant species, could provide a genomic snapshot of the genetic changes that occur during adaptation. Genomic analyses of AL, N-ML, and ML revealed that changes in the levels of genes related to transporters, chemotaxis, and nitrogen fixation likely reflect adaptations to different environmental conditions. Our study sheds light on the complex and dynamic nature of the evolution of rhizobia in response to changes in their environment and highlights the crucial role of genomic analysis in understanding these processes.
Assuntos
Mesorhizobium , Mesorhizobium/genética , Fixação de Nitrogênio , Nitrogenase/genética , Ecossistema , Água , Simbiose , FilogeniaRESUMO
BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections poses global challenges, with limited options available for targeted therapy. Polymyxin was been regarded as one of the most important last-resort antimicrobial agents. Many factors could accelerate the resistance evolution of polymyxin. Insertion sequence (IS) inserted into mgrB is the main polymyxin resistance mechanism in K. pneumoniae. In this study, two CRKPs (KP31157 and KP31311) were isolated from the urine of a patient, shifting from susceptible to resistant as the mgrB inserted by ISkpn14. We intended to explore the origin of the IS and underlying mechanisms resulting in polymyxin resistance. METHODS: The within-host evolution relationship and molecular features of both CRKPs were determined by pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). pKP31311_KPC-2 plasmid genome structures contained in the above two CRKPs were aligned with the homologic plasmids, retrieved from the NCBI genome database via comparative genomic analysis. The plasmids encoding ISkpn14 elements flanked by direct repeat (DR) or not were analyzed. The mRNA expression, plasmid curing and in vitro antibiotics inducing experiment were employed to understand the potential mechanism of polymyxin resistance. RESULTS: Both strains, sharing homology, exhibited polymyxin resistance due to the insertion of ISkpn14 into the mgrB gene, influenced by minocycline exposure. Minocycline and tigecycline could accelerate polymyxin resistance (P < 0.05), validated by an in vitro induction experiment. The ISkpn14 without DR flanked expressed about 4 times higher than that with DR. The frequency of the mgrB insertion induced by polymyxin was significantly reduced (0 strain detected) after the blaKPC-2-carrying plasmid was eliminated. CONCLUSIONS: This study provides direct experimental evidence that the ISkpn14 element causing mgrB inactivation and polymyxin resistance in K. pneumoniae originates from blaKPC-2-carrying plasmids. Minocycline exposure will accelerate the evolution of polymyxin resistance. Understanding the dynamics of IS transposition and its association with antibiotic exposure is crucial for developing effective strategies to reduce the emergence of polymyxin resistance in CRKP.
Assuntos
Antibacterianos , Carbapenêmicos , Infecções por Klebsiella , Klebsiella pneumoniae , Plasmídeos , Polimixinas , beta-Lactamases , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Plasmídeos/genética , Humanos , Polimixinas/farmacologia , Antibacterianos/farmacologia , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/tratamento farmacológico , beta-Lactamases/genética , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Sequenciamento Completo do Genoma , Elementos de DNA Transponíveis/genética , Farmacorresistência Bacteriana/genéticaRESUMO
Food is Medicine (FIM) programs to improve the accessibility of fruits and vegetables (FVs) or other healthy foods among patients with low income and diet-related chronic diseases are promising to improve food and nutrition security in the United States (US). However, FIM programs are relatively new and implementation guidance for healthcare settings using an implementation science lens is lacking. We used a narrative review to describe the evidence base on barriers and facilitators to FIM program integration in US healthcare settings following the Exploration, Preparation, Implementation, and Sustainment (EPIS) Framework. Evidence surrounding the EPIS Inner Context was a focus, including constructs Leadership, Organizational Characteristics, Quality and Fidelity Monitoring and Support, Organizational Staffing Processes, and Individual Characteristics. Peer-reviewed and grey literature about barriers and facilitators to FIM programs were of interest, defined as programs that screen and refer eligible patients with diet-related chronic disease experiencing food insecurity to healthy, unprepared foods. Thirty-one sources were included in the narrative review, including 22 peer-reviewed articles, four reports, four toolkits, and one thesis. Twenty-eight sources (90%) described EPIS Inner Context facilitators and 26 sources (84%) described FIM program barriers. The most common barriers and facilitators to FIM programs were regarding Quality and Fidelity Monitoring and Support (e.g., use of electronic medical records for tracking and evaluation, strategies to support implementation) and Organizational Staffing Processes (e.g., clear delineation of staff roles and capacity); although, barriers and facilitators to FIM programs were identified among all EPIS Inner Context constructs. We synthesized barriers and facilitators to create an EPIS-informed implementation checklist for healthcare settings for use among healthcare organizations/providers, partner organizations, and technical assistance personnel. We discuss future directions to align FIM efforts with implementation science terminology and theories, models, and frameworks to improve the implementation evidence base and support FIM researchers and practitioners.
Assuntos
Dieta Saudável , Humanos , Estados Unidos , Doença Crônica/terapia , Insegurança Alimentar , Atenção à Saúde/organização & administraçãoRESUMO
The well-known phenomenon of phase separation in synthetic polymers and proteins has become a major topic in biophysics because it has been invoked as a mechanism of compartment formation in cells, without the need for membranes. Most of the coacervates (or condensates) are composed of Intrinsically Disordered Proteins (IDPs) or regions that are structureless, often in interaction with RNA and DNA. One of the more intriguing IDPs is the 526-residue RNA-binding protein, Fused in Sarcoma (FUS), whose monomer conformations and condensates exhibit unusual behavior that are sensitive to solution conditions. By focussing principally on the N-terminus low-complexity domain (FUS-LC comprising residues 1-214) and other truncations, we rationalize the findings of solid-state NMR experiments, which show that FUS-LC adopts a non-polymorphic fibril structure (core-1) involving residues 39-95, flanked by fuzzy coats on both the N- and C-terminal ends. An alternate structure (core-2), whose free energy is comparable to core-1, emerges only in the truncated construct (residues 110-214). Both core-1 and core-2 fibrils are stabilized by a Tyrosine ladder as well as hydrophilic interactions. The morphologies (gels, fibrils, and glass-like) adopted by FUS seem to vary greatly, depending on the experimental conditions. The effect of phosphorylation is site-specific. Simulations show that phosphorylation of residues within the fibril has a greater destabilization effect than residues that are outside the fibril region, which accords well with experiments. Many of the peculiarities associated with FUS may also be shared by other IDPs, such as TDP43 and hnRNPA2. We outline a number of problems for which there is no clear molecular explanation.
Assuntos
Proteínas Intrinsicamente Desordenadas , Sarcoma , Humanos , Domínios Proteicos , Espectroscopia de Ressonância Magnética , Conformação Proteica , Fosforilação , Proteínas Intrinsicamente Desordenadas/química , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/química , Proteína FUS de Ligação a RNA/metabolismoRESUMO
AIM: To investigate the effect of dipeptidyl peptidase-4 inhibitors (DPP4-Is) and glucagon-like peptide-1 receptor agonists (GLP1-RAs) on diabetic foot ulcer (DFU) and DFU-related outcomes (lower limb amputation [LLA], DFU-related hospitalization and mortality). METHODS: We performed a cohort study with data from the Clinical Practice Research Datalink Aurum database with linkage to hospital data. We included people with type 2 diabetes starting treatment with metformin. Then we propensity score matched new users of DPP4-Is and sulphonylureas (N = 98 770), and new users of GLP1-RAs and insulin (N = 25 422). Cox proportional hazards models estimated the hazard ratios (HRs) for the outcomes. RESULTS: We observed a lower risk of DFU with both DPP4-I use versus sulphonylurea use (HR 0.88, 95% confidence interval [CI]: 0.79-0.97) and GLP1-RA use versus insulin use (HR 0.44, 95% CI: 0.32-0.60) for short-term exposure (≤ 400 days) and HR 0.74 (95% CI: 0.60-0.92) for long-term exposure (>400 days). Furthermore, the risks of hospitalization and mortality were lower with both DPP4-I use and GLP1-RA use. The risk of LLA was lower with GLP1-RA use. The results remained consistent across several sensitivity analyses. CONCLUSIONS: Incretin-based therapy was associated with a lower risk of DFU and DFU-related outcomes. This suggests benefits for the use of this treatment in people at risk of DFU.
Assuntos
Amputação Cirúrgica , Diabetes Mellitus Tipo 2 , Pé Diabético , Inibidores da Dipeptidil Peptidase IV , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hipoglicemiantes , Incretinas , Humanos , Pé Diabético/tratamento farmacológico , Pé Diabético/epidemiologia , Masculino , Feminino , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Incretinas/uso terapêutico , Incretinas/efeitos adversos , Pessoa de Meia-Idade , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Estudos de Coortes , Compostos de Sulfonilureia/uso terapêutico , Compostos de Sulfonilureia/efeitos adversos , Hospitalização/estatística & dados numéricos , Insulina/uso terapêutico , Metformina/uso terapêutico , Metformina/efeitos adversos , Modelos de Riscos ProporcionaisRESUMO
BACKGROUND: TANK-binding kinase 1 (TBK1) is a pivotal mediator of innate immunity, activated by receptors such as mitochondrial antiviral signaling protein (MAVS), stimulator of interferon genes (STING), and TIR-domain-containing adaptor inducing interferon-ß (TRIF). It modulates immune responses by exerting influence on the type I interferons (IFN-Is) signaling and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways, Over the past few years, TBK1 multifaceted role in both immune and inflammatory responses is increasingly recognized. METHODS AND RESULTS: This review aims to scrutinize how TBK1 operates within the NF-κB pathway and the interferon regulatory transcription factor 3 (IRF3)-dependent IFN-I pathways, highlighting the kinases and other molecules involved in these processes. This analysis reveals the distinctive characteristics of TBK1's involvement in these pathways. Furthermore, it has been observed that the role of TBK1 in exerting anti-inflammatory or pro-inflammatory effects is contingent upon varying pathological conditions, indicating a multifaceted role in immune regulation. DISCUSSION: TBK1's evolving role in various diseases and the potential of TBK1 inhibitors as therapeutic agents are explored. Targeting TBK1 may provide new strategies for treating inflammatory disorders and autoimmune diseases associated with IFN-Is, warranting further investigation.
RESUMO
OBJECTIVES: We aimed to evaluate the relationship between use of sodium-glucose cotransporter-2 inhibitors (SGLT2is) and incidence of various respiratory and infectious diseases and site-specific fractures. METHODS: Large randomized controlled trials (RCTs) of SGLT2is enrolling more than 400 subjects were included. Outcomes of interest were various serious adverse events regarding to respiratory and infectious disorders and site-specific fractures. Meta-analysis was done using risk ratio (RR) and 95% confidence interval (CI) as effect size. RESULTS: Thirty-two large RCTs were included in this meta-analysis. Use of SGLT2is was significantly associated with the lower incidences of 6 kinds of noninfectious respiratory diseases {e.g., Asthma (RR 0.64, 95% CI 0.43-0.96; P = 0.0299), Chronic obstructive pulmonary disease [COPD] (RR 0.75, 95% CI 0.62-0.91; P = 0.0027), and Respiratory failure (RR 0.78, 95% CI 0.61-0.99; P = 0.0447)} and 4 kinds of infectious respiratory diseases {e.g., Bronchitis (RR 0.61, 95% CI 0.46-0.81; P = 0.0007), and Pneumonia (RR 0.85, 95% CI 0.78-0.93; P = 0.0002)}. Use of SGLT2is was not significantly associated with the incidences of 31 kinds of site-specific fractures (e.g., Hip fracture, Femoral neck fracture, and Spinal fracture; P > 0.05). CONCLUSIONS: Our meta-analysis confirmed the benefits of SGLT2is against 6 kinds of noninfectious respiratory diseases (e.g., Asthma, COPD, and Respiratory failure) and 4 kinds of infectious respiratory diseases (e.g., Bronchitis, and Pneumonia). These findings suggest a likelihood that SGLT2is might be used to prevent or treat these respiratory diseases. Moreover, our meta-analysis for the first time revealed no association between use of SGLT2is and incidence of various site-specific fractures.