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2.
J Cardiovasc Pharmacol ; 84(1): 18-25, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38968565

RESUMO

ABSTRACT: Recent studies have revealed the benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in heart failure patients. However, their effects on acute myocardial infarction (AMI) remain uncertain. Therefore, we conducted this meta-analysis to assess the effectiveness of SGLT2i in patients with AMI with or without diabetes. We conducted a comprehensive search of PubMed, Embase, and Cochrane Library encompassing data from inception until November 30, 2023. Relevant studies comparing SGLT2i with placebo or non-SGLT2i in patients with AMI were included. The mean difference and/or odds ratio (OR) with 95% confidence intervals were pooled using a fixed-effects model when the heterogeneity statistic (I2) was less than 50%; otherwise, a random-effects model was employed. Four randomized controlled trials and 4 observational studies involving 9397 patients with AMI were included in this meta-analysis. Patients treated with SGLT2i exhibited a significantly lower rate of hospitalization for heart failure (OR = 0.50, 95% CI: 0.32-0.80) and all-cause death (OR = 0.65, 95% CI: 0.44-0.95) compared with those treated with placebo or non-SGLT2i. Furthermore, the use of SGLT2i was associated with a significant increase in left ventricular ejection fraction (mean difference = 1.90, 95% CI: 1.62-2.17) and a greater reduction of N-terminal prohormone of brain natriuretic peptide (OR = 0.88, 95% CI 0.82-0.94). Subgroup analysis revealed that in patients with diabetes, SGLT2i exhibited similar effects. The present meta-analysis provided evidence indicating the effectiveness of SGLT2i in patients with AMI; SGLT2i may serve as an additional therapeutic option for patients with AMI, regardless of the presence or absence of diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Infarto do Miocárdio , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Resultado do Tratamento , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/diagnóstico , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/diagnóstico , Estudos Observacionais como Assunto , Fatores de Risco , Medição de Risco , Recuperação de Função Fisiológica , Fatores de Tempo
3.
bioRxiv ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38979281

RESUMO

We present a model of directed investigation of KEGG pathway analysis, beginning with discrete correlate summation (DCS) clustering of Swiss-Prot sets. Dopamine and angiotensin related proteins define the boundary for pathway analyses upon a network of proteins also associated with a compositely defined matrix of Swiss-Prot keywords to provide a framework for their biological indices (Figure 1).

4.
Sci Total Environ ; 947: 174412, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977097

RESUMO

Hydraulic fracturing (HF) has substantially boosted global unconventional hydrocarbon production but has also introduced various environmental and operational challenges. Understanding the interactions between abundant and diverse microbial communities and chemicals, particularly polymers used for proppant delivery, thickening, and friction reduction, in HF water cycles is crucial for addressing these challenges. This review primarily examined the recent studies conducted in China, an emerging area for HF activities, and comparatively examined studies from other regions. In China, polyacrylamide (PAM) and its derivatives products became key components in hydraulic fracturing fluid (HFF) for unconventional hydrocarbon development. The microbial diversity of unconventional HF water cycles in China was higher compared to North America, with frequent detection of taxa such as Shewanella, Marinobacter, and Desulfobacter. While biodegradation, biocorrosion, and biofouling were common issues across regions, the mechanisms underlying these microbe-polymer interactions differed substantially. Notably, in HF sites in the Sichuan Basin, the use of biocides gradually decreased its efficiency to mitigate adverse microbial activities. High-throughput sequencing proved to be a robust tool that could identify key bioindicators and biodegradation pathways, and help select optimal polymers and biocides, leading to more efficient HFF systems. The primary aim of this study is to raise awareness about the interactions between microorganisms and polymers, providing fresh insights that can inform decisions related to enhanced chemical use and biological control measures at HF sites.

5.
J Nanobiotechnology ; 22(1): 436, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39044240

RESUMO

Cisplatin (DDP) is a prevalent chemotherapeutic agent used in tumor therapy, yet DDP-induced acute kidney injury (AKI) severely limits its clinical application. Antioxidants as reactive oxygen species (ROS) scavengers can circumvent this adverse effect while leading to the decrease of efficacy to tumor. Herein, we report ultrasmall ruthenium nanoparticles (URNPs) as switchable ROS scavengers/generators to alleviate DDP-induced AKI and improve its therapeutic efficacy. In the physiological environment of the kidney, URNPs mimic multi-enzyme activities, such as superoxide dismutase and catalase, effectively protecting the renal cell and tissue by down-regulating the increased ROS level caused by DDP and alleviating AKI. Specifically, URNPs are oxidized by high levels of H2O2 in the tumor microenvironment (TME), resulting in the generation of oxygen vacancies and Ru3+/Ru4+ ions. This unique structure transformation endows URNPs to generate singlet oxygen (1O2) under laser irradiation and hydroxyl radicals (∙OH) through a Fenton-like reaction in tumor cell and tissue. The simultaneous generation of multifarious ROS effectively improves the efficacy of DDP in vitro and in vivo. This TME-responsive ROS scavenger/generator acts as an adjuvant therapeutic agent to minimize side effects and improve the efficacy of chemotherapy drugs, providing a new avenue to chemotherapy and facilitating clinical tumor therapy.


Assuntos
Injúria Renal Aguda , Antineoplásicos , Cisplatino , Rim , Espécies Reativas de Oxigênio , Rutênio , Cisplatino/farmacologia , Animais , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Rim/efeitos dos fármacos , Rim/metabolismo , Humanos , Rutênio/química , Rutênio/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Peróxido de Hidrogênio/metabolismo , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Masculino , Antioxidantes/farmacologia , Antioxidantes/química
6.
Am J Case Rep ; 25: e943530, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037967

RESUMO

BACKGROUND Cryptococcosis is an invasive fungal infection caused by Cryptococcus species complex. C. neoformans is one of the pathogenic species within the genus. C. neoformans infections often present as an opportunistic infection in severely immunocompromised individuals. Infection of the pericardium in the setting of liver failure is uncommon. We present a case of cryptococcal pericarditis in a patient with liver failure. CASE REPORT A 47-year-old man with a past medical history of psoriatic arthritis, and alcohol use disorder presented to the emergency department with a 2-week history of progressively worsening generalized weakness, malaise, and yellowish skin changes. Physical examination revealed scleral icterus, jaundiced skin, and ascites. Initial laboratory workup revealed thrombocytopenia, transaminitis (aspartate transaminase (AST) level of 502 IU/L, alanine transaminase (ALT) level of 82 IU/L), hyperbilirubinemia (total bilirubin of 15.7 mg/dL), International Nationalized Ratio (INR) of 3.6, and lactic acidosis (lactic acid of 11.7 mmol/L). The patient developed encephalopathy and acute hypoxic respiratory failure requiring intubation. A bedside point-of-care cardiac ultrasound, performed following intubation, revealed a pericardial effusion without signs of tamponade. This finding was later confirmed by a formal transthoracic echocardiogram. Percutaneous pericardiocentesis was performed, and the pericardial fluid culture revealed the presence of C. neoformans. Human immunodeficiency virus (HIV) tests were negative. The patient received antifungal therapy. Due to his poor prognosis, he was transitioned to comfort care and eventually died. CONCLUSIONS This case report describes an unusual presentation of acute liver failure complicated by cryptococcal pericarditis, emphasizing the importance of considering atypical fungal infections in such patients.


Assuntos
Criptococose , Pericardite , Humanos , Masculino , Pessoa de Meia-Idade , Criptococose/diagnóstico , Criptococose/complicações , Pericardite/microbiologia , Pericardite/diagnóstico , Falência Hepática/etiologia , Cryptococcus neoformans/isolamento & purificação , Antifúngicos/uso terapêutico , Hospedeiro Imunocomprometido , Evolução Fatal
7.
Anal Methods ; 16(27): 4644-4652, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38946403

RESUMO

In order to develop a highly efficient H2S gas sensor at low working temperature, in this work, a kind of novel Ce-doped ZnCo2O4 hollow microspheres (Ce/ZnCo2O4 HMSs) were successfully synthesized using a template-free one-pot method, showing a sensitive response toward H2S. The microstructure and morphology of the material were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The gas-sensing performance of the composite was investigated, showing that the ZnCo2O4 doped with 6 mol% Ce had the highest response to 20 ppm H2S at a low operating temperature of 160 °C with a response value of 67.42, which was about 2 times higher than that of original ZnCo2O4. The prepared Ce/ZnCo2O4 HMS sensor in response to H2S exhibited a linear range of 0.1-200 ppm with a low detection limit of 0.1 ppm under the conditions of ambient humidity of 45% and ambient temperature of 20 °C. Meanwhile, it also possessed good selectivity, repeatability and reproducibility. The response value of the sensor decreased by 5.32% after 7 months of continuous monitoring of H2S in an atmospheric environment of a pig farm, indicating that the sensor had a long-term stability and continuous service life with important application prospects.

8.
Phytochemistry ; 226: 114206, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972440

RESUMO

Eighteen compounds including eleven previously undescribed diterpenes were isolated from the leaves of Croton mangelong. The structures were determined by HRESIMS, IR, NMR, X-ray diffraction and ECD spectroscopic analysis. All isolates were assayed for their anti-hyperglycemic activities in insulin resistance (IR) 3T3-L1 adipocytes, and compound 4 was tested for its anti-diabetic activity in vivo. Results suggested compound 4 could effectively reduce blood glucose level in diabetic SD rats in a dose of 30 mg/kg.

9.
Stem Cell Res Ther ; 15(1): 201, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971839

RESUMO

BACKGROUND: Dysfunction or deficiency of corneal epithelium results in vision impairment or blindness in severe cases. The rapid and effective regeneration of corneal epithelial cells relies on the limbal stem cells (LSCs). However, the molecular and functional responses of LSCs and their niche cells to injury remain elusive. METHODS: Single-cell RNA sequencing was performed on corneal tissues from normal mice and corneal epithelium defect models. Bioinformatics analysis was performed to confirm the distinct characteristics and cell fates of LSCs. Knockdown of Creb5 and OSM treatment experiment were performed to determine their roles of in corneal epithelial wound healing. RESULTS: Our data defined the molecular signatures of LSCs and reconstructed the pseudotime trajectory of corneal epithelial cells. Gene network analyses characterized transcriptional landmarks that potentially regulate LSC dynamics, and identified a transcription factor Creb5, that was expressed in LSCs and significantly upregulated after injury. Loss-of-function experiments revealed that silencing Creb5 delayed the corneal epithelial healing and LSC mobilization. Through cell-cell communication analysis, we identified 609 candidate regeneration-associated ligand-receptor interaction pairs between LSCs and distinct niche cells, and discovered a unique subset of Arg1+ macrophages infiltrated after injury, which were present as the source of Oncostatin M (OSM), an IL-6 family cytokine, that were demonstrated to effectively accelerate the corneal epithelial wound healing. CONCLUSIONS: This research provides a valuable single-cell resource and reference for the discovery of mechanisms and potential clinical interventions aimed at ocular surface reconstruction.


Assuntos
Plasticidade Celular , Células-Tronco do Limbo , Limbo da Córnea , Cicatrização , Animais , Camundongos , Epitélio Corneano/metabolismo , Epitélio Corneano/patologia , Epitélio Corneano/lesões , Células-Tronco do Limbo/citologia , Células-Tronco do Limbo/metabolismo , Limbo da Córnea/metabolismo , Limbo da Córnea/citologia , Limbo da Córnea/patologia , Camundongos Endogâmicos C57BL , Nicho de Células-Tronco , Cicatrização/genética
10.
Adv Sci (Weinh) ; : e2400934, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022985

RESUMO

Selective CO2 photoreduction to C2 hydrocarbons is significant but limited by the inadequate adsorption strength of the reaction intermediates and low efficiency of proton transfer. Herein, an ameliorative *CO adsorption and H2O activation strategy is realized via decorating bismuth oxychloride (BiOCl) nanostructures with different metal (Pt, Pd, and Au) species. Experimental and theoretical calculation results reveal that distinct *CO binding energies and *H acquisition abilities of the metal cocatalysts mediate the CO2 reduction activity and hydrocarbon selectivity. The relatively moderate *CO adsorption and *H supply over Pd/BiOCl endows it with the lowest free energy to generate *CHO, leading to its highest activity of hydrocarbon production. Specifically, the Pt cocatalyst can efficiently participate in H2O dissociation to deliver more *H for facilitating the protonation of the *CHO and *CHOH, thereby favoring CH4 production with 76.51% selectivity. A lower *H supply over Pd/BiOCl and Au/BiOCl results in a large energy barrier for *CHO or *CHOH protonation and thus a more thermodynamically favored OC─CHO coupling pathway, which endows them with vastly increased C2 hydrocarbon selectivity of 81.21% and 92.81%, respectively. The understanding of efficient C2 hydrocarbon production in this study sheds light on how materials can be engineered for photocatalytic CO2 reduction.

11.
Regen Biomater ; 11: rbae079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39022125

RESUMO

Biomarkers have been applied for toxicity assessment of biomaterials due to their advantages. However, research on biomarkers for biomaterials is still in its early stages. There is a lack of integrated analysis in biomarker research based on multiomics studies. Herein, we report a new approach for combining of gene/protein and metabolite multiomics to reveal biomarkers of nickel ion (Ni2+) cytotoxicity and the underlying mechanism. Firstly, differentially expressed genes and proteins were compared to screen gene/protein pairs exhibiting consistent differential expression within the same Ni2+-treated groups. Next, metabolic pathway analysis was carried out to reveal pathways in which gene/protein pairs and metabolites showed upstream and downstream relationships. Important networks composed of gene/protein pairs, metabolites and metabolic pathways and candidate biomarkers were subsequently identified. Through expression level and function validation, the gene/protein/metabolite biomarkers were confirmed, and the underlying mechanism was revealed: Ni2+ influenced the expression of the Rrm2 gene biomarker, which subsequently affected the expression of the RRM2 protein biomarker. These changes in turn impacted the levels of uric acid and uridine metabolite biomarkers, ultimately inhibiting DNA synthesis, suppressing cell proliferation, increasing intracellular ROS levels and reducing ATP content.

12.
Nanotechnology ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39025081

RESUMO

Flexible electronics, such as wearable displays, implantable electronics, soft robots, and smart skin, have garnered increasing attention. Despite notable advancements in research, a bottleneck remains at the product level due to the prevalent use of polymer-based materials, requiring encapsulation films for lifespan extension and reliable performance. Multilayer composites, incorporating thin inorganic layers to maintain low permeability towards moisture, oxygen, ions, etc., exhibit potential in achieving highly flexible barriers but encounter challenges stemming from interface instability between layers. This perspective offers a succinct review of strategies and provides atomic-scale interface modulation strategy utilizing atomic layer integration technology focused on enhancing the flexibility of high-barrier films. It delves into bendable multilayers with atomic-scale interface modulation strategies, encompassing internal stress and applied stress modulation, as well as stretchable composite structural designs such as gradient/hybrid, wavy, and island. These strategies showcase significant improvements in flexibility from bendable to stretchable while maintaining high barrier properties. Besides, optimized manufacturing methods, materials, and complex structure design based on atomic-scale interface engineering are provided, better aligning with the future development of flexible electronics. By laying the groundwork for these atomic-scale strategies, this perspective contributes to the evolution of flexible electronics, enhancing their flexibility, durability, and functionality.

13.
Sci Rep ; 14(1): 16659, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030232

RESUMO

Freeze-thaw cycles are frequently overlooked as a pivotal factor contributing to leakage and structural failures in clayey soil-impermeable barriers used in landfills or tailings repositories in regions subject to seasonal freezing. This investigation explores the recovery and residual strength properties of Jilin ball clay undergoing six freeze-thaw cycles, and assesses the pore structure characteristics through a series of nuclear magnetic resonance (NMR) tests. The results indicate that normal stress has a greater impact on peak recovery strength than dry density and rest periods. Cohesion increases earlier and more significantly during rest periods compared to internal friction angle. Although the pore diameter remains consistent within the micropores during the freeze-thaw cycles, the soil's structural integrity undergoes notable changes. The concluding analysis provides valuable insights for the construction and management of impermeable barriers in landfills or tailings repositories within seasonally frozen areas.

14.
J Basic Microbiol ; : e2400030, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39031597

RESUMO

Streptococcus suis is an important zoonotic pathogen, causing cytokine storms of Streptococcal toxic shock-like syndrome amongst humans after a wound infection into the bloodstream. To overcome the challenges of fever and leukocyte recruitment, invasive S. suis must deploy multiple stress responses forming a network and utilize proteases to degrade short-lived regulatory and misfolded proteins induced by adverse stresses, thereby adapting and evading host immune responses. In this study, we found that S. suis encodes multiple ATP-dependent proteases, including single-chain FtsH and double-subunit Clp protease complexes ClpAP, ClpBP, ClpCP, and ClpXP, which were activated as the fever of infected mice in vivo. The expression of genes ftsH, clpA/B/C, and clpP, but not clpX, were significantly upregulated in S. suis in response to heat stress, while were not changed notably under the treatments with several other stresses, including oxidative, acidic, and cold stimulation. FtsH and ClpP were required for S. suis survival within host blood under heat stress in vitro and in vivo. Deletion of ftsH or clpP attenuated the tolerance of S. suis to heat, oxidative and acidic stresses, and significantly impaired the bacterial survival within macrophages. Further analysis identified that repressor CtsR directly binds and controls the clpA/B/C and clpP operons and is relieved by heat stress. In summary, the deployments of multiple ATP-dependent proteases form a flexible heat stress response network that appears to allow S. suis to fine-tune the degradation or refolding of the misfolded proteins to maintain cellular homeostasis and optimal survival during infection.

15.
J Nanobiotechnology ; 22(1): 384, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951903

RESUMO

BACKGROUND: Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial issues and promote accelerated wound healing. In this investigation, we utilized electrospinning to fabricate microgel/nanofiber membranes encapsulating MXene-encapsulated microgels and chitosan/gelatin polymers. RESULTS: The film dressing facilitates programmed photothermal therapy (PPT) and mild photothermal therapy (MPTT) under near-infrared (NIR), showcasing swift and extensive antibacterial and biofilm-disrupting capabilities. The PPT effect achieves prompt sterilization within 5 min at 52 °C and disperses mature biofilm within 10 min. Concurrently, by adjusting the NIR power to induce local mild heating (42 °C), the dressing stimulates fibroblast proliferation and migration, significantly enhancing vascularization. Moreover, in vivo experimentation successfully validates the film dressing, underscoring its immense potential in addressing the intricacies of diabetic wounds. CONCLUSIONS: The MXene microgel-loaded nanofiber dressing employs temperature-coordinated photothermal therapy, effectively amalgamating the advantageous features of high-temperature sterilization and low-temperature promotion of wound healing. It exhibits rapid, broad-spectrum antibacterial and biofilm-disrupting capabilities, exceptional biocompatibility, and noteworthy effects on promoting cell proliferation and vascularization. These results affirm the efficacy of our nanofiber dressing, highlighting its significant potential in addressing the challenge of diabetic wounds struggling to heal due to infection.


Assuntos
Antibacterianos , Bandagens , Nanofibras , Terapia Fototérmica , Cicatrização , Cicatrização/efeitos dos fármacos , Nanofibras/química , Terapia Fototérmica/métodos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Biofilmes/efeitos dos fármacos , Quitosana/química , Masculino , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/complicações , Temperatura , Ratos , Raios Infravermelhos , Proliferação de Células/efeitos dos fármacos , Ratos Sprague-Dawley , Humanos , Infecção dos Ferimentos/terapia
16.
J Clin Invest ; 134(14)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-39007267

RESUMO

Emerging evidence has linked the dysregulation of N6-methyladenosine (m6A) modification to inflammation and inflammatory diseases, but the underlying mechanism still needs investigation. Here, we found that high levels of m6A modification in a variety of hyperinflammatory states are p65-dependent because Wilms tumor 1-associated protein (WTAP), a key component of the "writer" complex, is transcriptionally regulated by p65, and its overexpression can lead to increased levels of m6A modification. Mechanistically, upregulated WTAP is more prone to phase separation to facilitate the aggregation of the writer complex to nuclear speckles and the deposition of m6A marks on transcriptionally active inflammatory transcripts, thereby accelerating the proinflammatory response. Further, a myeloid deficiency in WTAP attenuates the severity of LPS-induced sepsis and DSS-induced IBD. Thus, the proinflammatory effect of WTAP is a general risk-increasing mechanism, and interrupting the assembly of the m6A writer complex to reduce the global m6A levels by targeting the phase separation of WTAP may be a potential and promising therapeutic strategy for alleviating hyperinflammation.


Assuntos
Adenosina , Inflamação , Animais , Camundongos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Adenosina/metabolismo , Adenosina/análogos & derivados , Humanos , Lipopolissacarídeos , Camundongos Knockout , Modelos Animais de Doenças , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Sepse/metabolismo , Sepse/genética , Sepse/patologia , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/genética , Proteínas de Ciclo Celular
17.
Nanoscale Horiz ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016031

RESUMO

Gallium nitride offers an ideal material platform for next-generation high-power electronics devices, which enable a spectrum of applications. The thermal management of the ever-growing power density has become a major bottleneck in the performance, reliability, and lifetime of the devices. GaN/diamond heterostructures are usually adopted to facilitate heat dissipation, given the extraordinary thermal conduction properties of diamonds. However, thermal transport is limited by the interfacial conductance at the material interface between GaN and diamond, which is associated with significant mechanical stress at the atomic level. In this work, we investigate the effect of mechanical strain perpendicular to the GaN/diamond interface on the interfacial thermal conductance of heterostructures using full-atom non-equilibrium molecular dynamics simulations. We found that the heterostructure exhibits severe mechanical stress at the interface in the absence of loading, which is due to lattice mismatch. Upon tensile/compressive loading, the interfacial stress is more pronounced, and the strain is not identical across the interface owing to the contrasting elastic moduli of GaN and diamond. In addition, the interfacial thermal conductance can be notably enhanced and suppressed by tensile and compressive strains, respectively, leading to a 400% variation in thermal conductance. More detailed analyses reveal that the change in interfacial thermal conductance is related to the surface roughness and interfacial bonding strength, as described by a generalized relationship. Moreover, phonon analyses suggest that the unequal mechanical deformation under compressive strain in GaN and diamond induces different frequency shifts in the phonon spectra, leading to an enhancement in phonon overlapping energy, which promotes phonon transport at the interface and elevates the thermal conductance and vice versa for tensile strain. The effect of strain on interface thermal conductance was investigated at various temperatures. Based on the mechanical tunability of thermal conductance, we propose a conceptual design for a mechanical thermal switch that regulates thermal conductance with excellent sensitivity and high responsiveness. This study offers a fundamental understanding of how mechanical strain can adjust interface thermal conductance in GaN/diamond heterostructures with respect to mechanical stress, deformation, and phonon properties. These results and findings lay the theoretical foundation for designing thermal management devices in a strain environment and shed light on developing intelligent thermal devices by leveraging the interplay between mechanics and thermal transport.

18.
Int J Mol Sci ; 25(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38891992

RESUMO

Class III peroxidases (CIII PRXs) are plant-specific enzymes with high activity that play key roles in the catalysis of oxidation-reduction reactions. In plants, CIII PRXs can reduce hydrogen peroxide to catalyze oxidation-reduction reactions, thereby affecting plant growth, development, and stress responses. To date, no systematic analysis of the CIII PRX gene family in litchi (Litchi chinensis Sonn.) has been documented, although the genome has been reported. In this study, a total of 77 CIII PRX (designated LcPRX) gene family members were predicted in the litchi genome to provide a reference for candidate genes in the responses to abiotic stresses during litchi growth and development. All of these LcPRX genes had different numbers of highly conserved PRX domains and were unevenly distributed across fifteen chromosomes. They were further clustered into eight clades using a phylogenetic tree, and almost every clade had its own unique gene structure and motif distribution. Collinearity analysis confirmed that there were eleven pairs of duplicate genes among the LcPRX members, and segmental duplication (SD) was the main driving force behind the LcPRX gene expansion. Tissue-specific expression profiles indicated that the expression levels of all the LcPRX family members in different tissues of the litchi tree were significantly divergent. After different abiotic stress treatments, quantitative real-time PCR (qRT-PCR) analysis revealed that the LcPRX genes responded to various stresses and displayed differential expression patterns. Physicochemical properties, transmembrane domains, subcellular localization, secondary structures, and cis-acting elements were also analyzed. These findings provide insights into the characteristics of the LcPRX gene family and give valuable information for further elucidating its molecular function and then enhancing abiotic stress tolerance in litchi through molecular breeding.


Assuntos
Regulação da Expressão Gênica de Plantas , Litchi , Família Multigênica , Filogenia , Estresse Fisiológico , Litchi/genética , Litchi/metabolismo , Litchi/enzimologia , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Peroxidases/genética , Peroxidases/metabolismo , Perfilação da Expressão Gênica
19.
Vaccines (Basel) ; 12(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38932317

RESUMO

A chimeric protein, formed by two fragments of the conserved nucleocapsid (N) and S2 proteins from SARS-CoV-2, was obtained as a recombinant construct in Escherichia coli. The N fragment belongs to the C-terminal domain whereas the S2 fragment spans the fibre structure in the post-fusion conformation of the spike protein. The resultant protein, named S2NDH, was able to form spherical particles of 10 nm, which forms aggregates upon mixture with the CpG ODN-39M. Both preparations were recognized by positive COVID-19 human sera. The S2NDH + ODN-39M formulation administered by the intranasal route resulted highly immunogenic in Balb/c mice. It induced cross-reactive anti-N humoral immunity in both sera and bronchoalveolar fluids, under a Th1 pattern. The cell-mediated immunity (CMI) was also broad, with positive response even against the N protein of SARS-CoV-1. However, neither neutralizing antibodies (NAb) nor CMI against the S2 region were obtained. As alternative, the RBD protein was included in the formulation as inducer of NAb. Upon evaluation in mice by the intranasal route, a clear adjuvant effect was detected for the S2NDH + ODN-39M preparation over RBD. High levels of NAb were induced against SARS-CoV-2 and SARS-CoV-1. The bivalent formulation S2NDH + ODN-39M + RBD, administered by the intranasal route, constitutes an attractive proposal as booster vaccine of sarbecovirus scope.

20.
Parasitol Res ; 123(6): 231, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829429

RESUMO

Cryptosporidium spp. are protozoa commonly found in domestic and wild animals. Limited information is available on Cryptosporidium in deer worldwide. In this study, 201 fecal samples were collected from Alpine musk deer on three farms in Gansu Province, China. Detection and subtyping of Cryptosporidium were performed by PCR and sequence analysis of the SSU rRNA and gp60 genes. The prevalence of Cryptosporidium infection in Alpine musk deer was 3.9% (8/201), with infection rates of 1.0% (1/100), 2.8% (1/36), and 9.2% (6/65) in three different farms. All positive samples for Cryptosporidium were from adult deer. Two Cryptosporidium species were identified, including C. parvum (n = 2) and C. xiaoi (n = 6). The C. parvum isolates were subtyped as IIdA15G1, while the C. xiaoi isolates were subtyped as XXIIIa (n = 2) and XXIIIg (n = 4). The IIdA15G1 subtype of C. parvum was found for the first time in deer. These results provide important insights into the identity and human infectious potential of Cryptosporidium in farmed Alpine musk deer.


Assuntos
Criptosporidiose , Cryptosporidium , Cervos , Fezes , Animais , Cervos/parasitologia , Criptosporidiose/parasitologia , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Cryptosporidium/classificação , China/epidemiologia , Fezes/parasitologia , Prevalência , DNA de Protozoário/genética , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Genótipo , DNA Ribossômico/genética , DNA Ribossômico/química
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