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1.
Phys Rev E ; 110(2-2): 025301, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39294972

RESUMO

Based on the mesoscopic scale, the lattice Boltzmann method (LBM) with an enthalpy-based model represented in the form of distribution functions is widely used in the liquid-solid phase transition process of energy storage materials due to its direct and relatively accurate characterization of the presence of latent heat of solidification. However, since the enthalpy distribution function itself contains the physical properties of the material, these properties are transferred along with the enthalpy distribution function during the streaming process. This leads to deviations between the enthalpy-based model when simulating the phase transition process of different materials mixed and the actual process. To address this issue, in this paper, we construct an enthalpy-based model for different types of materials. For multiple materials, various forms of enthalpy distribution functions are employed. This method still uses the form of enthalpy distribution functions for collisions and streaming processes among the same type of substance, while for heat transfer between different materials, it avoids the direct transfer of enthalpy distribution functions and instead applies a source term to the enthalpy distribution functions, characterizing the heat transfer between different materials through the energy change before and after mixing based on the temperature. To verify the accuracy of the method proposed in this paper, a detailed solidification model for two different materials is constructed using the example of water droplets solidifying in air, and the results are compared with experimental outcomes. The results of the simulation show that the model constructed in this paper is largely in line with the actual process.

2.
Inflammation ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088121

RESUMO

This study aims to explore the common pathogenic mechanisms of psoriasis and atopic dermatitis, two T-cell-mediated autoimmune diseases. Utilizing single-cell transcriptomic sequencing data, we revealed that Treg cells primarily express TIGIT in both psoriasis and atopic dermatitis, and identified a subset of macrophages that highly express SGK1. These cells can interact with T cells via the NECTIN2-TIGIT signaling pathway, inhibiting the differentiation of T cells into a pro-inflammatory phenotype, thereby uncovering a common immunoregulatory mechanism in both diseases. Furthermore, we discovered that inhibition of SGK1 exacerbates the inflammatory response in disease models of both conditions. These findings not only provide a new perspective for a common therapeutic strategy for psoriasis and atopic dermatitis but also highlight the importance of considering these molecular interactions in future treatments. Validation of these observations through further qPCR, immunofluorescence, and animal studies has identified potential new targets for the treatment of psoriasis and atopic dermatitis.

3.
Nat Microbiol ; 9(9): 2395-2409, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39030344

RESUMO

Genetic interactions identify functional connections between genes and pathways, establishing gene functions or druggable targets. Here we use CRISPRi-TnSeq, CRISPRi-mediated knockdown of essential genes alongside TnSeq-mediated knockout of non-essential genes, to map genome-wide interactions between essential and non-essential genes in Streptococcus pneumoniae. Transposon-mutant libraries constructed in 13 CRISPRi strains enabled screening of ~24,000 gene pairs. This identified 1,334 genetic interactions, including 754 negative and 580 positive interactions. Network analyses show that 17 non-essential genes pleiotropically interact with more than half the essential genes tested. Validation experiments confirmed that a 7-gene subset protects against perturbations. Furthermore, we reveal hidden redundancies that compensate for essential gene loss, relationships between cell wall synthesis, integrity and cell division, and show that CRISPRi-TnSeq identifies synthetic and suppressor-type relationships between both functionally linked and disparate genes and pathways. Importantly, in species where CRISPRi and Tn-Seq are established, CRISPRi-TnSeq should be straightforward to implement.


Assuntos
Sistemas CRISPR-Cas , Elementos de DNA Transponíveis , Genes Essenciais , Genoma Bacteriano , Streptococcus pneumoniae , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo , Genes Essenciais/genética , Genoma Bacteriano/genética , Elementos de DNA Transponíveis/genética , Redes Reguladoras de Genes , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Genes Bacterianos/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Inativação de Genes
4.
J Neurol Surg B Skull Base ; 85(4): 389-396, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38966302

RESUMO

Objective Biochemical remission rates of endoscopic endonasal transsphenoidal surgery (EETS) and its associated predictive factors were evaluated in patients with somatotrophin pituitary adenomas. Methods The patients who underwent EETS in Jinling Hospital were identified between 2011 and 2020. The surgeons' experience, preoperative insulin-like growth factor 1 (IGF-1), basal growth hormone (GH) levels, nadir GH levels, and the tumor characteristics were analyzed for their relationships with endocrine outcomes. Total 98 patients were included for single factor analysis and regression analysis. They were divided into three groups according to the admission chronologic order. Results The overall remission rate of the patients was 57% (56/98) for all the patients over 10 years. In the single factor analysis, we found that the tumor size, cavernous invasion, and sellar invasion were valuable to predict the endocrine outcome after surgery. As for the suprasellar invasion, no significant difference was found between the noninvasive group and the invasive group. The preoperative IGF-1 level ( p = 0.166), basal GH level ( p = 0.001), and nadir GH level ( p = 0.004) were also different between the remission group and the nonremission group in the single factor analysis. The logistic regression analysis indicated that the preoperative nadir GH (odds ratio = 0.930, 95% confidence interval = 0.891-0.972, p = 0.001) was a significant predictor for the endocrine outcomes after surgery. Conclusion The surgeons' experience is an important factor that can affect the patients' endocrine outcomes after surgery. The macroadenomas with lateral invasion are more difficult to cure. Patients with higher preoperative nadir GH levels are less likely to achieve remission.

5.
EMBO Rep ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026012

RESUMO

Genome transcription and replication of influenza A virus (FluA), catalyzed by viral RNA polymerase (FluAPol), are delicately controlled across the virus life cycle. A switch from transcription to replication occurring at later stage of an infection is critical for progeny virion production and viral non-structural protein NS2 has been implicated in regulating the switch. However, the underlying regulatory mechanisms and the structure of NS2 remained elusive for years. Here, we determine the cryo-EM structure of the FluAPol-NS2 complex at ~3.0 Å resolution. Surprisingly, three domain-swapped NS2 dimers arrange three symmetrical FluPol dimers into a highly ordered barrel-like hexamer. Further structural and functional analyses demonstrate that NS2 binding not only hampers the interaction between FluAPol and the Pol II CTD because of steric conflicts, but also impairs FluAPol transcriptase activity by stalling it in the replicase conformation. Moreover, this is the first visualization of the full-length NS2 structure. Our findings uncover key molecular mechanisms of the FluA transcription-replication switch and have implications for the development of antivirals.

6.
Oncol Res ; 32(6): 1079-1091, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827318

RESUMO

Approximately 30%-40% of growth hormone-secreting pituitary adenomas (GHPAs) harbor somatic activating mutations in GNAS (α subunit of stimulatory G protein). Mutations in GNAS are associated with clinical features of smaller and less invasive tumors. However, the role of GNAS mutations in the invasiveness of GHPAs is unclear. GNAS mutations were detected in GHPAs using a standard polymerase chain reaction (PCR) sequencing procedure. The expression of mutation-associated maternally expressed gene 3 (MEG3) was evaluated with RT-qPCR. MEG3 was manipulated in GH3 cells using a lentiviral expression system. Cell invasion ability was measured using a Transwell assay, and epithelial-mesenchymal transition (EMT)-associated proteins were quantified by immunofluorescence and western blotting. Finally, a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and invasiveness. The invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type GNAS. Consistently, the invasiveness of mutant GNAS-expressing GH3 cells decreased. MEG3 is uniquely expressed at high levels in GHPAs harboring mutated GNAS. Accordingly, MEG3 upregulation inhibited tumor cell invasion, and conversely, MEG3 downregulation increased tumor cell invasion. Mechanistically, GNAS mutations inhibit EMT in GHPAs. MEG3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/ß-catenin signaling pathway, which was further validated in vivo. Our data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/ß-catenin signaling pathway.


Assuntos
Cromograninas , Subunidades alfa Gs de Proteínas de Ligação ao GTP , Adenoma Hipofisário Secretor de Hormônio do Crescimento , Mutação , Invasividade Neoplásica , RNA Longo não Codificante , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Linhagem Celular Tumoral , Proliferação de Células/genética , Cromograninas/genética , Cromograninas/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Am Chem Soc ; 146(26): 17669-17678, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38905328

RESUMO

The genus Mycobacterium includes species such as Mycobacterium tuberculosis, which can cause deadly human diseases. These bacteria have a protective cell envelope that can be remodeled to facilitate their survival in challenging conditions. Understanding how such conditions affect membrane remodeling can facilitate antibiotic discovery and treatment. To this end, we describe an optimized fluorogenic probe, N-QTF, that reports on mycolyltransferase activity, which is vital for cell division and remodeling. N-QTF is a glycolipid probe that can reveal dynamic changes in the mycobacterial cell envelope in both fast- and slow-growing mycobacterial species. Using this probe to monitor the consequences of antibiotic treatment uncovered distinct cellular phenotypes. Even antibiotics that do not directly inhibit cell envelope biosynthesis cause conspicuous phenotypes. For instance, mycobacteria exposed to the RNA polymerase inhibitor rifampicin release fluorescent extracellular vesicles (EVs). While all mycobacteria release EVs, fluorescent EVs were detected only in the presence of RIF, indicating that exposure to the drug alters EV content. Macrophages exposed to the EVs derived from RIF-treated cells released lower levels of cytokines, suggesting the EVs moderate immune responses. These data suggest that antibiotics can alter EV content to impact immunity. Our ability to see such changes in EV constituents directly results from exploiting these chemical probes.


Assuntos
Corantes Fluorescentes , Mycobacterium tuberculosis , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Mycobacterium tuberculosis/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo , Humanos
8.
J Hazard Mater ; 475: 134924, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38880045

RESUMO

Nanofiltration (NF) is a promising technology in the treatment of microelectronic wastewater. However, the treatment of concentrate derived from NF system remains a substantial technical challenge, impeding the achievement of the zero liquid discharge (ZLD) goal in microelectronic wastewater industries. Herein, a ZLD system, coupling a two-stage NF technology with anaerobic biotechnology was proposed for the treatment of tetramethylammonium hydroxide (TMAH)-contained microelectronic wastewater. The two-stage NF system exhibited favorable efficacy in the removal of conductivity (96 %), total organic carbon (TOC, 90 %), and TMAH (96 %) from microelectronic wastewater. The membrane fouling of this system was dominated by organic fouling, with the second stage NF membrane experiencing a more serious fouling compared to the first stage membrane. The anaerobic biotechnology achieved a near-complete removal of TMAH and an 80 % reduction in TOC for the first stage NF concentrate. Methyloversatilis was the key genus involved in the anaerobic treatment of the microelectronic wastewater concentrate. Specific genes, including dmd-tmd, mtbA, mttB and mttC were identified as significant players in mediating the dehydrogenase and methyl transfer pathways during the process of TMAH biodegradation. This study highlights the potential of anaerobic biodegradation to achieve ZLD in the treatment of TMAH-contained microelectronic wastewater by NF system.


Assuntos
Biodegradação Ambiental , Filtração , Compostos de Amônio Quaternário , Águas Residuárias , Águas Residuárias/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Membranas Artificiais , Purificação da Água/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Reatores Biológicos , Resíduo Eletrônico , Nanotecnologia
9.
Bone ; 187: 117172, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38909879

RESUMO

Gain-of-function mutations in the low-density lipoprotein receptor-related protein 5 (LRP5) can cause high-bone-mass (HBM) phenotype, with 19 identified mutations so far. The A242T mutation in LRP5 has been found in 9 families, making it one of the most prevalent mutations. However, the correlation between the A242T mutation and HBM phenotype remains unverified in animal models. This study aimed to investigate the bone properties in a new transgenic mouse model carrying the LRP5 A241T missense mutation, equivalent to A242T in humans. Heterozygous Lrp5A241T mice were generated using CRISPR/Cas9 genome editing. Body weight increased with age from 4 to 16 weeks, higher in males than females, with no difference between Lrp5A241T mice and wild-type control. Micro-CT showed slightly longer femur and notably elevated trabecular bone mass of the femur and fifth lumbar spine with higher bone mineral density, bone volume fraction, and trabecular thickness in Lrp5A241T mice compared to wild-type mice. Additionally, increased cortical bone thickness and volume of the femur shaft and skull were observed in Lrp5A241T mice. Three-point bending tests of the tibia demonstrated enhanced bone strength properties in Lrp5A241T mice. Histomorphometry confirmed that the A241T mutation increased bone formation without affecting osteoblast number and reduced resorption activities in vivo. In vitro experiments indicated that the LRP5 A241T mutation enhanced osteogenic capacity of osteoblasts with upregulation of the Wnt signaling pathway, with no significant impact on the resorptive activity of osteoclasts. In summary, mice carrying the LRP5 A241T mutation displayed high bone mass and quality due to enhanced bone formation and reduced bone resorption in vivo, potentially mediated by the augmented osteogenic potential of osteoblasts. Continued investigation into the regulatory mechanisms of its bone metabolism and homeostasis may contribute to the advancement of novel therapeutic strategies for bone disorders.


Assuntos
Densidade Óssea , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Camundongos Transgênicos , Fenótipo , Animais , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Feminino , Masculino , Densidade Óssea/genética , Osteoblastos/metabolismo , Mutação/genética , Camundongos , Osso e Ossos/metabolismo , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Microtomografia por Raio-X , Tamanho do Órgão , Osteogênese/genética , Peso Corporal/genética , Fêmur/diagnóstico por imagem , Fêmur/patologia , Fêmur/metabolismo , Osteoclastos/metabolismo
10.
Br J Dermatol ; 191(3): 405-418, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38752329

RESUMO

BACKGROUND: Psoriasis is a T cell-mediated chronic inflammatory skin condition characterized by the interaction of T cells with various cell types, forming an inflammatory microenvironment that sustains psoriatic inflammation. Homeostasis of these tissue-resident T cells is supported by fibroblasts, the primary structural cells in the dermis. In psoriasis, there is increased expression of matrix metalloproteinase 2 (MMP2), mediating structural alterations in skin tissues and modulating inflammation. Additionally, the CD100-plexin-B2 (PLXNB2) axis is known to enhance psoriasis inflammation via keratinocytes, and CD103 levels are associated with the severity of psoriasis upon relapse. OBJECTIVES: To elucidate the role of fibroblasts and the MMP2-CD100 axis in modulating psoriasis inflammation. METHODS: CD100 expression and function in psoriasis were assessed using immunofluorescence, enzyme-linked immunosorbent assay, single-cell transcriptome sequencing, cellular interaction analyses and quantitative reverse transcriptase polymerase chain reaction. CD8+ T cells from people with psoriasis were isolated using magnetic beads, to investigate the regulatory effect of MMP2 on CD100 expression on their membranes. Single-cell transcriptome sequencing, spatial transcriptome sequencing, mimetic timing analysis, immunofluorescence and flow cytometry were used to determine the origin of MMP2 and its impact on CD103+ CD8+ T cells. The hypotheses were further validated in vivo using MMP2 and CD100 inhibitors. RESULTS: Soluble CD100 (sCD100) was significantly upregulated in both psoriatic lesions and peripheral blood, amplifying psoriasis inflammation by promoting the production of inflammatory cytokines by keratinocytes, fibroblasts and endothelial cells via the sCD100-PLXNB2 axis. Fibroblasts that highly expressed MMP2 (MMP2hi) exacerbated psoriasis symptoms by facilitating CD100 shedding from CD8+ T-cell membranes. Additionally, it was shown that fibroblasts enhance the upregulation of the CD8+ T-cell residency factor CD103 in co-cultures with CD8+ T cells. Inhibitors targeting MMP2 and CD100 were effective in reducing inflammation in an imiquimod-induced psoriasis model. CONCLUSIONS: Our findings underscore the pivotal role of MMP2hi fibroblasts in the amplification and recurrence of inflammatory responses in psoriasis. These fibroblasts augment psoriasis inflammation through the CD100-PLXNB2 axis by facilitating CD100 shedding on CD8+ T-cell membranes and by upregulating CD103, thereby enhancing CD8+ T-cell residency.


Psoriasis is a chronic skin condition. It involves the interaction of cells of the immune system (called T cells) with other cells in the body, causing inflammation. The main structural cells in the skin are called fibroblasts. Fibroblasts are important in skin healing and disease. In psoriasis, the body produces more of an enzyme called MMP2. MMP2 brings about structural alterations in skin tissues and controls inflammation. Proteins called CD100 and PLXNB2 increase the inflammation in psoriasis through another type of skin cell called keratinocytes. We investigated the role of fibroblasts and MMP2 and CD100 in psoriasis. To do this, the production and function of CD100 were assessed using a variety of laboratory techniques. We found that by controlling the enzymes MMP2 and MMP9, fibroblasts cause the release of CD100 from some T cells, encouraging the production of substances that promote inflammation, worsening psoriasis. This also caused fibroblasts to produce more MMP2, forming a cycle that increases the inflammation seen in psoriasis. Fibroblasts were found to increase the level of another protein called CD103 on some T cells, affecting how often psoriasis flares up. Our study highlights the important role of fibroblasts that express a lot of MMP2 in the inflammation found in people with psoriasis.


Assuntos
Antígenos CD , Linfócitos T CD8-Positivos , Fibroblastos , Metaloproteinase 2 da Matriz , Psoríase , Psoríase/imunologia , Humanos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Fibroblastos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Antígenos CD/metabolismo , Camundongos , Animais , Queratinócitos/metabolismo , Masculino , Feminino , Pele/imunologia , Pele/patologia , Cadeias alfa de Integrinas/metabolismo , Células Cultivadas , Semaforinas
11.
Front Psychiatry ; 15: 1361184, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800066

RESUMO

Background: The global impact of the COVID-19 pandemic had significantly altered the daily routines of people worldwide. This study aimed to compare how sleeptime and depression among Chinese residents had differed between periods during and outside the epidemic. Furthermore, it delved into the interactive effect of age in this relationship. Method: Utilizing data from the China Health and Retirement Longitudinal Study (CHARLS) study in 2015 and the recently released data from 2020, which covered the pandemic period. Depression was assessed using Center for Epidemiologic Studies Depression Scale (CESD-10), considering a score of 10 or higher as indicative of depression. Participants were categorized based on age, specifically those aged 60 years and older. multivariate logistic regression and interaction analyses were employed to assess the interplay of age, supported by subgroup and sensitivity analyses to reinforce our findings. Results: The 2020 database comprised 19,331 participants, while the 2015 database had 10,507 participants. Our findings demonstrated a significant correlation between sleeptime and depression in both unadjusted models and models adjusted for all variables in both datasets (p<0.001). Upon stratifying by age and adjusting for relevant factors, we identified an interaction effect among age, sleeptime, and depression (p=0.004 for the interaction in the 2020 database, compared to 0.004 in 2015). The restricted cubic spline analysis in both datasets showcased a nonlinear relationship between sleeptime and depression. Conclusions: During both epidemic and non-epidemic periods in China, there existed a correlation between sleep duration and depression, which interacts with age.

12.
Nat Commun ; 15(1): 4065, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744895

RESUMO

Proteolysis-targeting chimeras (PROTACs) represent a new therapeutic modality involving selectively directing disease-causing proteins for degradation through proteolytic systems. Our ability to exploit targeted protein degradation (TPD) for antibiotic development remains nascent due to our limited understanding of which bacterial proteins are amenable to a TPD strategy. Here, we use a genetic system to model chemically-induced proximity and degradation to screen essential proteins in Mycobacterium smegmatis (Msm), a model for the human pathogen M. tuberculosis (Mtb). By integrating experimental screening of 72 protein candidates and machine learning, we find that drug-induced proximity to the bacterial ClpC1P1P2 proteolytic complex leads to the degradation of many endogenous proteins, especially those with disordered termini. Additionally, TPD of essential Msm proteins inhibits bacterial growth and potentiates the effects of existing antimicrobial compounds. Together, our results provide biological principles to select and evaluate attractive targets for future Mtb PROTAC development, as both standalone antibiotics and potentiators of existing antibiotic efficacy.


Assuntos
Antibacterianos , Proteínas de Bactérias , Mycobacterium smegmatis , Mycobacterium tuberculosis , Proteólise , Proteólise/efeitos dos fármacos , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium smegmatis/metabolismo , Mycobacterium smegmatis/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Antibacterianos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Aprendizado de Máquina
13.
Int J Biol Macromol ; 271(Pt 2): 132604, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788866

RESUMO

A series of ternary polysaccharide hydrogels were facile prepared by incorporating carboxymethyl cellulose (CMC) into the carboxymethyl chitosan/carboxymethyl ß-cyclodextrin (CMCS/CMCD) complex solution based on multiple physical interactions. Structure properties of the CMC/CMCS/CMCD hydrogels were revealed by FTIR, XRD, SEM, and TG. The rheological and texture properties, temperature/pH-response behaviors, biocompatablity, and antimicrobial activity of the hydrogels were determined in detail. These results showed that the existence of electron force and hydrogen bond among three components leading to formation of the hydrogels, displaying good mechanical characteristic, stable solid-like rheological properties, controllable swelling and degradation behaviors, and excellent biocompatibility. Additionally, the swelling kinetics can be well described by the Schott's pseudo second order model. Moreover, the hydrogels loaded with cinnamic acid (CA) exhibited good antimicrobial activity against both Staphylococcus aureus and Escherichia coli, and the antimicrobial activity was related to the composition of the prepared hydrogels. The novel ternary polysaccharide hydrogels may have good application prospects in food and bio-medicine.


Assuntos
Carboximetilcelulose Sódica , Quitosana , Hidrogéis , Staphylococcus aureus , beta-Ciclodextrinas , Quitosana/química , Quitosana/análogos & derivados , Quitosana/farmacologia , Hidrogéis/química , beta-Ciclodextrinas/química , Carboximetilcelulose Sódica/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Reologia , Antibacterianos/farmacologia , Antibacterianos/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Temperatura , Concentração de Íons de Hidrogênio , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana
14.
PLoS Comput Biol ; 20(4): e1012015, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38620017

RESUMO

Recent advances in single-cell sequencing technology have provided opportunities for mathematical modeling of dynamic developmental processes at the single-cell level, such as inferring developmental trajectories. Optimal transport has emerged as a promising theoretical framework for this task by computing pairings between cells from different time points. However, optimal transport methods have limitations in capturing nonlinear trajectories, as they are static and can only infer linear paths between endpoints. In contrast, stochastic differential equations (SDEs) offer a dynamic and flexible approach that can model non-linear trajectories, including the shape of the path. Nevertheless, existing SDE methods often rely on numerical approximations that can lead to inaccurate inferences, deviating from true trajectories. To address this challenge, we propose a novel approach combining forward-backward stochastic differential equations (FBSDE) with a refined approximation procedure. Our FBSDE model integrates the forward and backward movements of two SDEs in time, aiming to capture the underlying dynamics of single-cell developmental trajectories. Through comprehensive benchmarking on multiple scRNA-seq datasets, we demonstrate the superior performance of FBSDE compared to other methods, highlighting its efficacy in accurately inferring developmental trajectories.


Assuntos
Modelos Teóricos , Processos Estocásticos
15.
Nat Commun ; 15(1): 3088, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600064

RESUMO

Transcriptional regulation is a critical adaptive mechanism that allows bacteria to respond to changing environments, yet the concept of transcriptional plasticity (TP) - the variability of gene expression in response to environmental changes - remains largely unexplored. In this study, we investigate the genome-wide TP profiles of Mycobacterium tuberculosis (Mtb) genes by analyzing 894 RNA sequencing samples derived from 73 different environmental conditions. Our data reveal that Mtb genes exhibit significant TP variation that correlates with gene function and gene essentiality. We also find that critical genetic features, such as gene length, GC content, and operon size independently impose constraints on TP, beyond trans-regulation. By extending our analysis to include two other Mycobacterium species -- M. smegmatis and M. abscessus -- we demonstrate a striking conservation of the TP landscape. This study provides a comprehensive understanding of the TP exhibited by mycobacteria genes, shedding light on this significant, yet understudied, genetic feature encoded in bacterial genomes.


Assuntos
Mycobacterium tuberculosis , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano/genética , Óperon/genética , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , Regulação Bacteriana da Expressão Gênica
16.
Clin Microbiol Infect ; 30(5): 660-665, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38295989

RESUMO

OBJECTIVES: To explore the seroprevalence of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies in non-HIV cryptococcal meningitis (CM) and assess its predictive value for survival. METHODS: This is a retrospective study of 12 years of non-HIV CM. We detected serum anti-GM-CSF autoantibodies, and evaluated the clinical features and outcomes, together with the exploration of prognostic factors for 2-week and 1-year survival. RESULTS: A total of 584 non-HIV CM cases were included. 301 of 584 patients (51.5%) were phenotypically healthy. 264 Cryptococcus isolates were obtained from cerebrospinal fluid (CSF) culture, of which 251 were identified as C. neoformans species complex and 13 as C. gattii species complex. Thirty-seven of 455 patients (8.1%) tested positive for serum anti-GM-CSF autoantibodies. Patients with anti-GM-CSF autoantibodies were more susceptible to C. gattii species complex infection (66.7% vs. 6.3%; p < 0.001) and more likely to develop pulmonary mass lesions with a diameter >3 centimetres (42.9% vs. 6.5%; p 0.001). Of 584 patients 16 (2.7%) died within 2 weeks, 77 of 563 patients (13.7%) died at 1 year, and 93 of 486 patients (19.1%) lived with disabilities at 1 year. Univariant Cox regression analysis found that anti-GM-CSF autoantibodies were associated with lower 1-year survival (HR, 2.66; 95% CI, 1.34-5.27; p 0.005). Multivariable Cox proportional hazards modelling revealed that CSF cryptococcal antigen titres ≥1:1280 were associated with both, reduced 2-week and 1-year survival rates (HR, 5.44; 95% CI, 1.23-24.10; p 0.026 and HR, 5.09; 95% CI, 1.95-13.26; p 0.001). DISCUSSION: Presence of serum anti-GM-CSF autoantibodies is predictive of poor outcomes, regardless of host immune status and the causative Cryptococcus species complex.


Assuntos
Autoanticorpos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Meningite Criptocócica , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoanticorpos/sangue , Autoanticorpos/líquido cefalorraquidiano , Cryptococcus gattii/imunologia , Cryptococcus neoformans/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Meningite Criptocócica/mortalidade , Meningite Criptocócica/imunologia , Meningite Criptocócica/diagnóstico , Prognóstico , Estudos Retrospectivos , Estudos Soroepidemiológicos
17.
J Neurol Surg A Cent Eur Neurosurg ; 85(1): 7-13, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37220786

RESUMO

BACKGROUND: The endoscopic endonasal approach (EEA) and the endoscopic supraorbital keyhole approach (eSKA) provide minimally invasive access to tuberculum sellae (TS) tumors. Evaluation of the operating maneuverability is helpful for approach selection. Herein, we compared the two approaches and aimed to provide quantitative anatomic data for surgical decision-making in the management of TS lesions. METHODS: Fifteen dissections were performed on five silicone-injected cadaveric heads. The EEA and eSKA (both right and left) were performed on each head. Surgical freedom and working angles in the axial and sagittal planes were calculated using the stereotactic navigation system in the selected six targets: the midpoint of the leading edge of the sphenoid sinus (leSS), the midpoint of the edge of the dorsum sellae (eDS), the ipsilateral medial opticocarotid recess (imOCR), the contralateral medial opticocarotid recess (cmOCR), the ipsilateral lateral opticocarotid recess (ilOCR), and the contralateral lateral opticocarotid recess (clOCR). RESULTS: The surgical freedom at the ilOCR and the axial working angles at the leSS, ilOCR, and imOCR (imOCR with excessive manipulation of the optic apparatus) were greater in the eSKA. The EEA provided greater surgical freedom and/or working angles at most targets than eSKA (the surgical freedom at the imOCR, cmOCR, clOCR, and eDS; the axial working angles at the cmOCR and clOCR; and the sagittal working angles at the leSS, imOCR, cmOCR, clOCR, and eDS). CONCLUSION: The EEA provides greater surgical freedom and working angles for paramedian lesions, whereas the eSKA provides better surgical maneuverability for lesions with lateral extension.


Assuntos
Neuroendoscopia , Humanos , Nariz , Sela Túrcica/cirurgia , Procedimentos Neurocirúrgicos , Cadáver
18.
Mar Drugs ; 21(12)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38132952

RESUMO

Six previously undescribed cytosporone derivatives (phomotones A-E (1-5) and phomotone F (13)), two new spiro-alkanol phombistenes A-B (14-15), and seven known analogs (6-12) were isolated from the mangrove endophytic fungus Phomopsis sp. QYM-13. The structures of these compounds were elucidated using spectroscopic data analysis, electronic circular dichroism (ECD), and 13C NMR calculations. Compound 14 features an unprecedented 1,6-dioxaspiro[4.5]decane ring system. All isolates were evaluated for their inhibitory effect on nitric oxide (NO) in LPS-induced RAW264.7 cells. The results showed that compounds 1, 6, 8, and 11 exhibited potent bioactivities by comparing with positive control. Then, compound 1 displayed the anti-inflammatory effect by inhibiting the MAPK/NF-κB signaling pathways. Molecular docking further revealed the possible mechanism of compound 1 interaction with ERK protein.


Assuntos
Fungos , Phomopsis , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Transdução de Sinais , Estrutura Molecular
19.
bioRxiv ; 2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38014062

RESUMO

Human challenge experiments could greatly accelerate the development of a tuberculosis (TB) vaccine. Human challenge for tuberculosis requires a strain that can both replicate in the host and be reliably cleared. To accomplish this, we designed Mycobacterium tuberculosis (Mtb) strains featuring up to three orthogonal kill switches, tightly regulated by exogenous tetracyclines and trimethoprim. The resultant strains displayed immunogenicity and antibiotic susceptibility similar to wild-type Mtb under permissive conditions. In the absence of supplementary exogenous compounds, the strains were rapidly killed in axenic culture, mice and nonhuman primates. Notably, the strain that contained three kill switches had an escape rate of less than 10 -10 per genome per generation and displayed no relapse in a SCID mouse model. Collectively, these findings suggest that this engineered Mtb strain could be a safe and effective candidate for a human challenge model.

20.
Res Sq ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37790329

RESUMO

Transcriptional regulation is a critical adaptive mechanism that allows bacteria to respond to changing environments, yet the concept of transcriptional plasticity (TP) remains largely unexplored. In this study, we investigate the genome-wide TP profiles of Mycobacterium tuberculosis (Mtb) genes by analyzing 894 RNA sequencing samples derived from 73 different environmental conditions. Our data reveal that Mtb genes exhibit significant TP variation that correlates with gene function and gene essentiality. We also found that critical genetic features, such as gene length, GC content, and operon size independently impose constraints on TP, beyond trans-regulation. By extending our analysis to include two other Mycobacterium species -- M. smegmatis and M. abscessus -- we demonstrate a striking conservation of the TP landscape. This study provides a comprehensive understanding of the TP exhibited by mycobacteria genes, shedding light on this significant, yet understudied, genetic feature encoded in bacterial genomes.

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