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1.
Zhongguo Gu Shang ; 37(4): 387-91, 2024 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-38664210

RESUMEN

OBJECTIVE: To study the incidence rate of sinus tarsi syndrome after lateral ankle sprain and observe the clinical efficacy of sinus tarsal corticosteroid injections. METHODS: From January 2021 to Janury 2022, 391 patients with lateral ankle sprain and 88 patients with sinus tarsi syndrome using corticosteroid injections (compound betamethasone 1 ml+ lidocaine hydrochloride 4 ml) were retrospectively analyzed. There were 22 males and 66 females, aged from 29 to 60 years old with an average of (41.00±7.52) years old, duration of the disease from 1 to 12 months with an average of (5.6±4.2) months. The visual analogue scale(VAS) and American Orthopedic Foot and Ankle Society(AOFAS) scores were collected before, 1 month, 3 months, 6 months, and 12 months after treatment. RESULTS: All 88 patients completed a 12-month follow-up. The incidence rate of sinus tarsi syndrome after lateral ankle sprain was 22.5%. One month after treatment, VAS was 1.20±0.89, AOFAS score was 88.70±7.04. Three months after treatment, VAS was 1.60±1.35, AOFAS score was 85.20±10.95. Six months after treatment, VAS 2.35±1.39, AOFAS 80.30±9.75. Twelve months after treatment, VAS was 2.80±1.51, AOFAS score was 79.1±9.94. Significant differences were found before and after treatment at all four time points of follow-up(P<0.05). CONCLUSION: The results of this study showed that the incidence rate of sinus tarsi syndrome after lateral ankle sprain was 22.5%. Corticosteroid injections were effective in the short term with a 65% recurrence rate of symptoms within 1 year. For patients with no significant long-term effect of conservative treatment, clinicians may explore alternative approaches, including options like ankle arthroscopy.


Asunto(s)
Traumatismos del Tobillo , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Estudios Retrospectivos , Corticoesteroides/uso terapéutico , Corticoesteroides/administración & dosificación , Síndrome , Esguinces y Distensiones
3.
Clin Transl Sci ; 17(4): e13787, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38558535

RESUMEN

The purpose of this study was to evaluate the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of frunexian (formerly known as EP-7041 and HSK36273) injection, a small molecule inhibitor of activated coagulation factor XI (FXIa), in healthy Chinese adult volunteers. This study was a randomized, placebo- and positive-controlled, sequential, ascending-dose (0.3/0.6/1.0/1.5/2.25 mg/kg/h) study of 5-day continuous intravenous infusions of frunexian. Frunexian administration exhibited an acceptable safety profile with no bleeding events. Steady state was rapidly reached with a median time ranging from 1.02 to 1.50 h. The mean half-life ranged from 1.15 to 1.43 h. Frunexian plasma concentration at a steady state and area under the concentration-time curve exhibited dose-proportional increases. The dose-escalation study of frunexian demonstrated its progressively enhanced capacities to prolong activated partial thromboplastin time (aPTT) and inhibit FXIa activity. The correlations between PK and PD biomarkers (aPTT/baseline and FXI clotting activity/baseline) were described by the two Emax models, with the EC50 values of 8940 and 1300 ng/mL, respectively. Frunexian exhibits good safety and PK/PD properties, suggesting it is a promising candidate for anticoagulant drug.


Asunto(s)
Anticoagulantes , Coagulación Sanguínea , Adulto , Humanos , Tiempo de Tromboplastina Parcial , Voluntarios Sanos , China , Método Doble Ciego , Relación Dosis-Respuesta a Droga
4.
Heliyon ; 10(6): e27845, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38560685

RESUMEN

Objective: To study the histopathological staging of atrophic lesions of the gastric mucosa. Methods: Histology and immunohistochemistry were used to closely examine 2144 specimens of atrophic gastric mucosa that were taken from endoscopic biopsies. Results: When the gastric mucosa epithelium is affected by infection, chemical stimulation, immune factors, genetic factors, and other factors, it may cause an atrophy of gastric mucosa epithelium and a decrease in the number of glands, intestinal metaplasia, hyperplasia of smooth muscle fibers, and atrophy of stem cells in the proliferative zone. In this study, we characterized the above lesions as atrophic lesions of the gastric mucosa. Based on the morphological and histological characteristics of the lesion, as well as the law of cell proliferation and transformation during its occurrence and development, we propose five stages. We also noted the onset age, gender correlation, and histopathological characteristics of each stage of gastric mucosal atrophies. Conclusion: Understanding the pathological staging of gastric mucosal atrophy is essential for treating patients correctly and keeping track of changes in malignant cells. It is also very important in preventing the initiation of gastric cancer or from getting worse.

5.
Front Bioeng Biotechnol ; 12: 1342340, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38567086

RESUMEN

Orthopedic implants are the most commonly used fracture fixation devices for facilitating the growth and development of incipient bone and treating bone diseases and defects. However, most orthopedic implants suffer from various drawbacks and complications, including bacterial adhesion, poor cell proliferation, and limited resistance to corrosion. One of the major drawbacks of currently available orthopedic implants is their inadequate osseointegration at the tissue-implant interface. This leads to loosening as a result of immunological rejection, wear debris formation, low mechanical fixation, and implant-related infections. Nanotechnology holds the promise to offer a wide range of innovative technologies for use in translational orthopedic research. Nanomaterials have great potential for use in orthopedic applications due to their exceptional tribological qualities, high resistance to wear and tear, ability to maintain drug release, capacity for osseointegration, and capability to regenerate tissue. Furthermore, nanostructured materials possess the ability to mimic the features and hierarchical structure of native bones. They facilitate cell proliferation, decrease the rate of infection, and prevent biofilm formation, among other diverse functions. The emergence of nanostructured polymers, metals, ceramics, and carbon materials has enabled novel approaches in orthopaedic research. This review provides a concise overview of nanotechnology-based biomaterials utilized in orthopedics, encompassing metallic and nonmetallic nanomaterials. A further overview is provided regarding the biomedical applications of nanotechnology-based biomaterials, including their application in orthopedics for drug delivery systems and bone tissue engineering to facilitate scaffold preparation, surface modification of implantable materials to improve their osteointegration properties, and treatment of musculoskeletal infections. Hence, this review article offers a contemporary overview of the current applications of nanotechnology in orthopedic implants and bone tissue engineering, as well as its prospective future applications.

6.
World J Clin Cases ; 12(8): 1497-1503, 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38576820

RESUMEN

BACKGROUND: Patients rarely develop complicated infections in thyroid cysts. Here, we describe a patient with chronic infected unilateral giant thyroid cyst related to diabetes mellitus (DM). CASE SUMMARY: A 66-year-old male was admitted due to an evident neck lump for 5 d after approximately 40 years of gradually progressive neck mass and 7 years of DM. Doppler ultrasound and computed tomography scan showed a giant lump in the left thyroid gland lobe. He was diagnosed with a large thyroid nodule complicated by tracheal dislocation and had surgical indications. Surgical exploration revealed evident inflammatory edema and exudation between the left anterior neck muscles, the nodule and glandular tissue. Fortunately, inflammatory lesions did not affect major neck vessels. Finally, a left partial thyroidectomy was performed. Macroscopic observation showed that the cystic thyroid mass consisted of extensive cystic wall calcification and was rich in massive rough sand-like calculi content and purulent matter. Postoperative pathology confirmed benign thyroid cyst with chronic infection. CONCLUSION: The progression of this chronic infectious unilateral giant thyroid cyst may have been related to DM, and identifying blood vessels involvement can prevent serious complications during operation.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38656857

RESUMEN

Graph Attention (GA) which aims to learn the attention coefficients for graph edges has achieved impressive performance in GNNs on many graph learning tasks. However, existing GAs are usually learned based on edges' (or connected nodes') features which fail to fully capture the rich structural information of edges. Some recent research attempts to incorporate the structural information into GA learning but how to fully exploit them in GA learning is still a challenging problem. To address this challenge, in this work, we propose to leverage a new Replicator Dynamics model for graph attention learning, termed Graph Replicator Attention (GRA). The core of GRA is our derivation of replicator dynamics based sparse attention diffusion which can explicitly learn context-aware and sparse preserved graph attentions via a simple self-supervised way. Moreover, GRA can be theoretically explained from an energy minimization model. This provides a more theoretical justification for the proposed GRA method. Experiments on several graph learning tasks demonstrate the effectiveness and advantages of the proposed GRA method on ten benchmark datasets.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38660885

RESUMEN

OBJECTIVE: To investigate the incidence of and risk factors for potential drug-drug interactions (DDIs) among elderly patients with corona virus disease 2019 (-COVID-19) in hospital and to explore management strategies to reduce the occurrence of potential DDIs and ensure patient medication safety. MATERIALS AND METHODS: This was a descriptive, retrospective cross-sectional study among patients aged 65 years and older who were hospitalized with COVID-19. Potential DDIs associated with prescriptions containing two or more medicines were analyzed with Lexicomp software, the incidence of DDIs was calculated, recommendations for medication adjustment were formulated, and the χ2-test and binary logistic regression were used to analyze related risk factors. RESULTS: A total of 772 prescriptions were analyzed, 527 (68.26) of which involved 5,732 potential DDIs. The results of this study showed that a total of 152 (28.84%) prescriptions had 270 X risk class potential DDIs (i.e., avoid combining), 313 (59.39%) prescriptions had 1,161 D risk class potential DDIs (i.e., consider therapy modification), and 476 (90.32%) prescriptions had 4,301 C risk class potential DDIs (i.e., monitor therapy). The study findings showed that the total number of drugs (p < 0.001), the length of hospital stay (p < 0.001), and the number of comorbidities (p < 0.001) were risk factors affecting the occurrence of potential DDIs. CONCLUSION: This study identified factors associated with potential DDIs, which can assist in changing medication strategies, preventing adverse drug reactions, and improving clinical efficacy.

9.
J Biomater Sci Polym Ed ; : 1-22, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38652755

RESUMEN

Titanium (Ti) implants are widely used in orthopedic and dental applications due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation on implant surfaces pose a significant risk of postoperative infections and complications. Conventional surface modifications often lack long-lasting antibacterial efficacy, necessitating the development of novel coatings with enhanced antimicrobial properties. This study aims to develop a novel Ag-TiO2-OTS (Silver-Titanium dioxide-Octadecyltrichlorosilane, ATO) nanocomposite coating, through a chemical plating method. By employing a 'resist-killing-disintegrate' approach, the coating is designed to inhibit bacterial adhesion effectively, and facilitate pollutant removal with lasting effects. Characterization of the coatings was performed using spectroscopy, electron microscopy, and contact angle analysis. Antibacterial efficacy, quantitatively evaluated against E. coli and S. aureus over 168 h, showed a significant reduction in bacterial adhesion by 76.6% and 66.5% respectively, and bacterial removal rates were up to 83.8% and 73.3% in comparison to uncoated Ti-base material. Additionally, antibacterial assays indicated that the ratio of the Lifshitz-van der Waals apolar component to electron donor surface energy components significantly influences bacterial adhesion and removal, underscoring a tunable parameter for optimizing antibacterial surfaces. Biocompatibility assessments with the L929 cell line revealed that the ATO coatings exhibited excellent biocompatibility, with minimal cytotoxicity and no significant impact on cell proliferation or apoptosis. The ATO coatings provided a multi-functionality surface that not only resists bacterial colonization but also possesses self-cleaning capabilities, thereby marking a substantial advancement in the development of antibacterial coatings for medical implants.

10.
Neural Netw ; 175: 106283, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38604007

RESUMEN

Emotion-cause pair extraction (ECPE) is a challenging task that aims to automatically identify pairs of emotions and their causes from documents. The difficulty of ECPE lies in distinguishing valid emotion-cause pairs from many irrelevant ones. Most previous methods have primarily focused on utilizing multi-task learning to extract semantic information solely from documents without explicitly encoding the relations between clauses. We propose a new approach that incorporates textual entailment paradigm aiming to infer the entailment relationship between the original document as the premise and the clauses or pairs described as the hypothesis. Our approach designs label-view hypothesis templates to improve ECPE by filtering out irrelevant emotion and cause clauses. Furthermore, we formulate candidate emotion-cause pairs as hypothesis statements, and define explicit multi-view symmetric templates to capture the emotion-cause relation semantics. The text entailment recognition for ECPE is finally implemented by fusing multi-view semantic information using a simplified capsule network. Our proposed model achieves state-of-the-art performance on ECPE compared to previous baselines. More importantly, this work demonstrates a novel effective way of applying the textual entailment paradigm to ECPE or clause-level causal discovery by designing multi-view hypothesis inference and information fusion.

12.
Water Res ; 256: 121617, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38642535

RESUMEN

The traditional electrochemical descaling process exhibits drawbacks, including low OH- utilization efficiency, constrained cathode deposition area, and protracted homogeneous precipitation time. Consequently, this study introduces a novel membrane-free electrochemical separation-filtering crystallization (MFES-FC) coupling process to treat circulating cooling water (CCW). In the membrane-free electrochemical separation (MFES) system, OH- is rapidly extracted by pump suction from the porous cathode boundary layer solution, preventing neutralization with H+, thereby enhancing the removal of Ca2+ and Mg2+. Experimental results indicate that the pH of the pump suction water can swiftly increase from 8.13 to 11.42 within 10 min. Owing to the high supersaturation of the pump suction water, this study couples the MFES with a filtration crystallization (FC) system that employs activated carbon as the medium. This approach captures scale particles to enhance water quality and expedites the homogeneous precipitation of hardness ions, shortening the treatment time while further augmenting the removal rate. After the MFES-FC treatment, the single-pass removal rates for total hardness, Ca2+ hardness, Mg2+ hardness, and alkalinity in the effluent reached 92 %, 97 %, 64 %, and 67 %, respectively, with turbidity of 3 NTU, current efficiency of 86.6 %, and energy consumption of 7.19 kWh·kg-1 CaCO3. This coupling process facilitates an effective removal of hardness and alkalinity at a comparatively low cost, offering a new reference and inspiration for advancements in electrochemical descaling technology.

13.
Int Wound J ; 21(4): e14807, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38591163

RESUMEN

Skin Cutaneous Melanoma (SKCM) is a form of cancer that originates in the pigment-producing cells, known as melanocytes, of the skin. Delay wound healing is often correlated with the occurrence of and progression of SKCM. In this comprehensive study, we investigated the intricate roles of two important wound healing genes in SKCM, including Matrix Metalloproteinase-2 (MMP2) and Matrix Metalloproteinase-9 (MMP9). Through a multi-faceted approach, we collected clinical samples, conducted molecular experiments, including RT-qPCR, bisulphite sequencing, cell culture, cell Counting Kit-8, colony formation, and wound healing assays. Beside this, we also used various other databases/tools/approaches for additional analysis including, UALCAN, GEPIA, HPA, MEXPRESS, cBioPortal, KM plotter, DrugBank, and molecular docking. Our results revealed a significant up-regulation of MMP2 and MMP9 in SKCM tissues compared to normal counterparts. Moreover, promoter methylation analysis suggested an epigenetic regulatory mechanism. Validations using TCGA datasets and immunohistochemistry emphasized the clinical relevance of MMP2 and MMP9 dysregulation. Functional assays demonstrated their synergistic impact on proliferation and migration in SKCM cells. Furthermore, we identified potential therapeutic candidates, Estradiol and Calcitriol, through drug prediction and molecular docking analyses. These compounds exhibited binding affinities, suggesting their potential as MMP2/MMP9 inhibitors. Overall, our study elucidates the diagnostic, prognostic, and therapeutic implications of MMP2 and MMP9 in SKCM, shedding light on their complex interplay in SKCM occurrence and progression.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/genética , Melanoma/terapia , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/terapia , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz , Simulación del Acoplamiento Molecular , Cicatrización de Heridas/genética , Mutación , Metilación
14.
Open Med (Wars) ; 19(1): 20240898, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38463518

RESUMEN

Photothermal therapy (PTT) of nanomaterials is an emerging novel therapeutic strategy for breast cancer. However, there exists an urgent need for appropriate strategies to enhance the antitumor efficacy of PTT and minimize damage to surrounding normal tissues. Piezo1 might be a promising novel photothermal therapeutic target for breast cancer. This study aims to explore the potential role of Piezo1 activation in the hyperthermia therapy of breast cancer cells and investigate the underlying mechanisms. Results showed that the specific agonist of Piezo1 ion channel (Yoda1) aggravated the cell death of breast cancer cells triggered by heat stress in vitro. Reactive oxygen species (ROS) production was significantly increased following heat stress, and Yoda1 exacerbated the rise in ROS release. GSK2795039, an inhibitor of NADPH oxidase 2 (NOX2), reversed the Yoda1-mediated aggravation of cellular injury and ROS generation after heat stress. The in vivo experiments demonstrate the well photothermal conversion efficiency of TiCN under the 1,064 nm laser irradiation, and Yoda1 increases the sensitivity of breast tumors to PTT in the presence of TiCN. Our study reveals that Piezo1 activation might serve as a photothermal sensitizer for PTT, which may develop as a promising therapeutic strategy for breast cancer.

15.
Inflammation ; 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436811

RESUMEN

Diabetic retinopathy (DR) is a diabetes-associated complication that poses a threat to vision, distinguished by persistent and mild inflammation of the retinal microvasculature. The activation of microglia plays a crucial role in driving this pathological progression. Previous investigations have demonstrated that ubiquitin-specific peptidase 25 (USP25), a deubiquitinating enzyme, is involved in the regulation of immune cell activity. Nevertheless, the precise mechanisms through which USP25 contributes to the development of DR remain incompletely elucidated. Firstly, we have demonstrated the potential mechanism by which ROCKs can facilitate microglial activation and augment the synthesis of inflammatory mediators through the modulation of NF-κB signaling pathways in a high-glucose milieu. Furthermore, our study has provided novel insights by demonstrating that the regulatory role of USP25 in the secretion of proinflammatory factors is mediated through the involvement of ROCK in modulating the expression of NF-κB and facilitating the nuclear translocation of the phosphatase NF-κB. This regulatory mechanism plays a crucial role in modulating the activation of microglial cells within a high-glycemic environment. Hence, USP25 emerges as a pivotal determinant for the inflammatory activation of microglial cells, and its inhibition exhibits a dual effect of promoting retinal neuron survival while suppressing the inflammatory response in the retina. In conclusion, the promotion of diabetic retinopathy (DR) progression by USP25 is attributed to its facilitation of microglial activation induced by high glucose levels, a process mediated by the ROCK pathway. These findings highlight the importance of considering USP25 as a potential therapeutic target for the management of diabetic neuroinflammation.

16.
Curr Eye Res ; : 1-11, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38482878

RESUMEN

PURPOSE: To explore the role of coagulation and fibrinolytic factors, and the potential mechanism of platelet aggregation in the pathogenesis of retinal vein occlusion. METHODS: Coagulation and fibrinolytic parameters in patients with retinal vein occlusion were determined using hemagglutinin and HISCL-5000. Relationships between these elevated parameters and factors representing typical clinical manifestations of retinal vein occlusion were examined, and these parameters were analyzed using a STRING database to indicate the potential role of platelet aggregation. Platelet glycoprotein IIb/IIIa (GPIIb/IIIa) levels were evaluated by flow cytometry after antiplatelet treatment in patients and mouse models. Furthermore, the GPIIb/IIIa ligand fibrinogen in peripheral blood and retina of mouse models was assessed by the turbidimetric method and real-time PCR, respectively. RESULTS: In patients, significant increases in peripheral blood fibrinogen and GPIIb/IIIa levels were observed (p = 0.0040, p < 0.0001, respectively). A positive correlation was observed between macular thickness (MT) and both fibrinogen and GPIIb/IIIa (r = 0.4528, p = 0.0063; r = 0.3789, p = 0.0427, respectively). After intravitreal injections of anti-vascular endothelial growth factor drugs, a significant reduction in fibrinogen levels was observed (p = 0.0072). In addition, the use of antiplatelet drugs resulted in a significant decrease in GPIIb/IIIa (p < 0.0001). In a mouse model, antiplatelet therapy significantly reduced both peripheral blood and retina fibrinogen levels and the overall rate of vein occlusion 3 days after occlusion (p < 0.0005). In addition, the reduction in GPIIb/IIIa levels after antiplatelet therapy was remarkable. CONCLUSION: Fibrinogen and GPIIb/IIIa may be involved in retinal vein occlusion and blocking platelet aggregation may be a new therapeutic approach for retinal vein occlusion.

17.
Small ; : e2305789, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38482934

RESUMEN

Designing highly active and robust catalysts for the oxygen evolution reaction is key to improving the overall efficiency of the water splitting reaction. It has been previously demonstrated that evaporation induced self-assembly (EISA) can be used to synthesize highly porous and high surface area cerate-based fluorite nanocatalysts, and that substitution of Ce with 50% rare earth (RE) cations significantly improves electrocatalyst activity. Herein, the defect structure of the best performing nanocatalyst in the series are further explored, Nd2 Ce2 O7 , with a combination of neutron diffraction and neutron pair distribution function analysis. It is found that Nd3 + cation substitution for Ce in the CeO2 fluorite lattice introduces higher levels of oxygen Frenkel defects and induces a partially reduced RE1.5 Ce1.5 O5 + x phase with oxygen vacancy ordering. Significantly, it is demonstrated that the concentration of oxygen Frenkel defects and improved electrocatalytic activity can be further enhanced by increasing the compositional complexity (number of RE cations involved) in the substitution. The resulting novel compositionally-complex fluorite- (La0.2 Pr0.2 Nd0.2 Tb0.2 Dy0.2 )2 Ce2 O7 is shown to display a low OER overpotential of 210 mV at a current density of 10 mAcm-2 in 1M KOH, and excellent cycling stability. It is suggested that increasing the compositional complexity of fluorite nanocatalysts expands the ability to tailor catalyst design.

18.
Small ; : e2311897, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38456762

RESUMEN

Compartmentalization is a powerful concept to integrate multiscale components with diverse functionalities into miniature architectures. Inspired by evolution-optimized cell compartments, synthetic core-shell capsules enable storage of actives and on-demand delivery of programmed functions, driving scientific progress across various fields including adaptive materials, sustainable electronics, soft robotics, and precision medicine. To simultaneously maximize structural stability and environmental sensitivity, which are the two most critical characteristics dictating performance, diverse nanoparticles are incorporated into microcapsules with a dense shell and a liquid core. Recent studies have revealed that these nano-additives not only enhance the intrinsic properties of capsules including mechanical robustness, optical behaviors, and thermal conductivity, but also empower dynamic features such as triggered release, deformable structures, and fueled mobility. In this review, the physicochemical principles that govern nanoparticle assembly during microencapsulation are examined in detail and the architecture-controlled functionalities are outlined. Through the analysis of how each primary method implants nanoparticles into microcapsules, their distinct spatial organizations within the core-shell structures are highlighted. Following a detailed discussion of the specialized functions enabled by specific nanoparticles, the vision of the required fundamental insights and experimental studies for this class of microcarriers to fulfill its potential are sketched.

19.
Nucleic Acids Res ; 52(7): 3856-3869, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38477346

RESUMEN

The genetic diversities of subpopulations drive the evolution of pathogens and affect their ability to infect hosts and cause diseases. However, most studies to date have focused on the identification and characterization of adaptive mutations in single colonies, which do not accurately reflect the phenotypes of an entire population. Here, to identify the composition of variant subpopulations within a pathogen population, we developed a streamlined approach that combines high-throughput sequencing of the entire population cells with genotyping of single colonies. Using this method, we reconstructed a detailed quorum-sensing (QS) evolutionary trajectory in Pseudomonas aeruginosa. Our results revealed a new adaptive mutation in the gacS gene, which codes for a histidine kinase sensor of a two-component system (TCS), during QS evolution. This mutation reduced QS activity, allowing the variant to sweep throughout the whole population, while still being vulnerable to invasion by the emerging QS master regulator LasR-null mutants. By tracking the evolutionary trajectory, we found that mutations in gacS facilitated QS-rewiring in the LasR-null mutant. This rapid QS revertant caused by inactive GacS was found to be associated with the promotion of ribosome biogenesis and accompanied by a trade-off of reduced bacterial virulence on host cells. In conclusion, our findings highlight the crucial role of the global regulator GacS in modulating the progression of QS evolution and the virulence of the pathogen population.


Asunto(s)
Proteínas Bacterianas , Evolución Molecular , Mutación , Pseudomonas aeruginosa , Percepción de Quorum , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidad , Percepción de Quorum/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Virulencia/genética , Transactivadores/genética , Transactivadores/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Regulación Bacteriana de la Expresión Génica , Histidina Quinasa/genética , Histidina Quinasa/metabolismo
20.
Int J Biol Macromol ; 265(Pt 2): 130980, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38508569

RESUMEN

D-allulose, an ideal low-calorie sweetener, is primarily produced through the isomerization of d-fructose using D-allulose 3-epimerase (DAE; EC 5.1.3.30). Addressing the gap in available immobilized DAE enzymes for scalable commercial D-allulose production, three core-shell structured organic-inorganic composite silica-based carriers were designed for efficient covalent immobilization of DAE. Natural inorganic diatomite was used as the core, while 3-aminopropyltriethoxysilane (APTES), polyethyleneimine (PEI), and chitosan organic layers were coated as the shells, respectively. These tailored carriers successfully formed robust covalent bonds with DAE enzyme conjugates, cross-linked via glutaraldehyde, and demonstrated enzyme activities of 372 U/g, 1198 U/g, and 381 U/g, respectively. These immobilized enzymes exhibited an expanded pH tolerance and improved thermal stability compared to free DAE. Particularly, the modified diatomite with PEI exhibited a higher density of binding sites than the other carriers and the PEI-coated immobilized DAE enzyme retained 70.4 % of its relative enzyme activity after ten cycles of reuse. This study provides a promising method for DAE immobilization, underscoring the potential of using biosilica-based organic-inorganic composite carriers for the development of robust enzyme systems, thereby advancing the production of value-added food ingredients like D-allulose.


Asunto(s)
Tierra de Diatomeas , Enzimas Inmovilizadas , Racemasas y Epimerasas , Racemasas y Epimerasas/metabolismo , Enzimas Inmovilizadas/metabolismo , Concentración de Iones de Hidrógeno , Fructosa/metabolismo , Estabilidad de Enzimas
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