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1.
Small ; : e2400732, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764258

RESUMO

Currently, methicillin-resistant Staphylococcus aureus (MRSA)-induced osteomyelitis is a clinically life-threatening disease, however, long-term antibiotic treatment can lead to bacterial resistance, posing a huge challenge to treatment and public health. In this study, glucose-derived carbon spheres loaded with zinc oxide (ZnO@HTCS) are successfully constructed. This composite demonstrates the robust ability to generate reactive oxygen species (ROS) under ultrasound (US) irradiation, eradicating 99.788% ± 0.087% of MRSA within 15 min and effectively treating MRSA-induced osteomyelitis infection. Piezoelectric force microscopy tests and finite element method simulations reveal that the ZnO@HTCS composite exhibits superior piezoelectric catalytic performance compared to pure ZnO, making it a unique piezoelectric sonosensitizer. Density functional theory calculations reveal that the formation of a Mott-Schottky heterojunction and an internal piezoelectric field within the interface accelerates the electron transfer and the separation of electron-hole pairs. Concurrently, surface vacancies of the composite enable the adsorption of a greater amount of oxygen, enhancing the piezoelectric catalytic effect and generating a substantial quantity of ROS. This work not only presents a promising approach for augmenting piezoelectric catalysis through construction of a Schottky heterojunction interface but also provides a novel, efficient therapeutic strategy for treating osteomyelitis.

2.
Environ Res ; 252(Pt 2): 118821, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615793

RESUMO

How microzooplanktonic ciliate adaptative strategies differ across diatom bloom and non-diatom bloom areas in the Arctic Ocean remains poorly documented. To address this gap, two different situations were categorized in the Arctic Ocean at summer 2023: diatom bloom stations (DBS) (genus Thalassiosira, chain-like) and non-diatom bloom stations (nDBS). Total abundance of ciliate at 3 m and 25 m in DBS was 2.8 and 1.8 folds higher than in nDBS, respectively. Aloricate ciliates were singled out in both DBS and nDBS, whilst their average abundance and biomass of large size-fraction (>50 µm) in former were 4.5-5.6 folds higher than in latter. Regarding tintinnids, high abundance of Ptychocylis acuta (Bering Strait species) mainly occurred at DBS, coupled with distribution of co-occurring Pacific-origin species Salpingella sp.1, collectively suggested a strong intrusion of Pacific Inflow during summer 2023. Additionally, presence of high abundance of Acanthostomella norvegica and genus Parafavella in nDBS might indicate the trajectory of the Transpolar Drift. Alternatively, tintinnids can serve as credible bioindicators for either monitoring currents or evaluating microzooplankton Borealization. Average abundance of total ciliate within 15-135 µm body-size spectrum in DBS was higher than nDBS. Moreover, spearman's rank correlation between biotic and abiotic analysis revealed that temperature and dissolved oxygen at DBS determined tintinnid species richness and ciliate total abundance, respectively. The results clearly demonstrate that remarkable divergences in large size-fraction of ciliate abundance between DBS and nDBS validate their irreplaceable role in controlling phytoplankton outbreak and associated biological processes in polar seas.

3.
Heliyon ; 10(8): e29671, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660243

RESUMO

Background: The Proximal Femoral Nail Antirotation (PFNA) device is the most commonly used implant to fix unstable femoral trochanteric fractures (UFTFs), but it has a relatively high incidence of complications. Due to this factor, the modified intramedullary nail (MIN) was created to treat patients with UFTFs. The aim was to exhibit the MIN and make a comparison with PFNA and InterTAN using biomechanical methods. Methods: An adult UFTF model was developed using Mimics software. The PFNA, InterTAN nail, and MIN models were drawn referring to the corresponding parameters and installed in the fracture models. Vertical, anteroposterior (AP) bending, and torsion loads of the femoral head were set in advance and loaded onto the fracture models. The value of maximal displacement and von Mises stress was evaluated via finite element analysis (FEA). Results: The MIN model had smaller values for maximal displacement than that of the PFNA model, and the increase in displacement was less pronounced for the MIN compared to PFNA under increasing vertical loads. For the indicator of von Mises stress, the MIN model showed lower stress compared with the PFNA model in vertical loads ranging from 300 N to 2100 N. Except for the maximal stress at implants under AP bending loads, the MIN demonstrated the most superior biomechanical properties under AP bending and torsional loads. Conclusion: The MIN offered obvious advantages in terms of mechanical stability and stress distribution among the three studied implants, providing a promising implant option for patients with UFTFs.

4.
Mar Environ Res ; 198: 106482, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38626628

RESUMO

Neuston, situated at the air-sea interface, stands as a crucial frontier in the realm of the global warming. Despite its unique habitat, there remains a need to substantiate the composition, diel dynamic and biotic-abiotic interaction of neustonic zooplankton in the tropical seas. In this study, we present rare observational data on neustonic zooplankton (0-20 cm) in the oligotrophic tropical South China Sea (SCS) during the summer of 2022. A total of eighteen samples were collected and analyzed, revealing the presence of fourteen taxa from eight phyla. The most prevalent group was Cypridina, accounting for 33.7% of the total abundance, followed by copepods (29.0%) and jellyfish (10.9%). Within copepods, the genus Pontella exhibited the highest relative abundance (38.0%). Additionally, each neuston taxon displayed unique diel distribution patterns. Cypridina was the most abundant taxon during the night (40.4%), while it shifted to copepod dominance during the day (50.4%). Among copepods, genus Pontella and larvae were dominant groups at night (44.7%) and during the day (30.0%), respectively. Moreover, a multivariate biota-environment analysis demonstrated that temperature, pH, dissolved oxygen and Si(OH)4 significantly impacted neuston composition. Notably, both jellyfish and sea snails showed a significant positive correlation with temperature, suggesting their potential dominance in the neuston community in response to future global warming in the oligotrophic tropical seas. This study lays a robust foundation for recognizing the neuston community in the oceanic SCS, and helps evaluate the long-term risks to neuston habitats under climate changes.

5.
Acta Biomater ; 179: 284-299, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494084

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is the primary pathogenic agent responsible for epidermal wound infection and suppuration, seriously threatening the life and health of human beings. To address this fundamental challenge, we propose a heterojunction nanocomposite (Ca-CN/MnS) comprised of Ca-doped g-C3N4 and MnS for the therapy of MRSA-accompanied wounds. The Ca doping leads to a reduction in both the bandgap and the singlet state S1-triplet state T2 energy gap (ΔEST). The Ca doping also facilitates the two-photon excitation, thus remarkably promoting the separation and transfer of 808 nm near-infrared (NIR) light-triggered electron-hole pairs together with the built-in electric field. Thereby, the production of reactive oxygen species and heat are substantially augmented nearby the nanocomposite under 808 nm NIR light irradiation. Consequently, an impressive photocatalytic MRSA bactericidal efficiency of 99.98 ± 0.02 % is achieved following exposure to NIR light for 20 min. The introduction of biologically functional elements (Ca and Mn) can up-regulate proteins such as pyruvate kinase (PKM), L-lactate dehydrogenase (LDHA), and calcium/calmodulin-dependent protein kinase (CAMKII), trigger the glycolysis and calcium signaling pathway, promote cell proliferation, cellular metabolism, and angiogenesis, thereby expediting the wound-healing process. This heterojunction nanocomposite, with its precise charge-transfer pathway, represents a highly effective bactericidal and bioactive system for treating multidrug-resistant bacterial infections and accelerating tissue repair. STATEMENT OF SIGNIFICANCE: Due to the bacterial resistance, developing an antibiotic-free and highly effective bactericidal strategy to treat bacteria-infected wounds is critical. We have designed a heterojunction consisting of calcium doped g-C3N4 and MnS (Ca-CN/MnS) that can rapidly kill methicillin-resistant Staphylococcus aureus (MRSA) without damaging normal tissue through a synergistic effect of two-photon stimulated photothermal and photodynamic therapy. In addition, the release of trace amounts of biofunctional elements Mn and Ca triggers glycolysis and calcium signaling pathways that promote cellular metabolism and cell proliferation, contributing to tissue repair and wound healing.


Assuntos
Cálcio , Glicólise , Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Animais , Cálcio/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Fototerapia , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/patologia , Infecção dos Ferimentos/tratamento farmacológico , Humanos , Nanocompostos/química , Cicatrização/efeitos dos fármacos , Camundongos , Raios Infravermelhos
6.
Front Bioeng Biotechnol ; 12: 1353677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464545

RESUMO

Purpose: Surgical treatment is the main treatment method for femoral intertrochanteric fractures (FIFs), however, there are lots of implant-related complications after surgery. Our team designed a new intramedullary nail (NIN) to manage such fractures. The purpose of this study was to introduce this new implant and compare it with proximal femoral nail antirotation (PFNA) and InterTAN for treating FIFs. Methods: An AO/OTA 31-A1.3 FIF model was built and three fixation models were created via finite element method, comprising PFNA, InterTAN, and the NIN. Vertical, anteroposterior (A-P) bending, and torsional loads were simulated and applied to the three fixation models. Displacement and stress distribution were monitored. In order to compare PFNA and the NIN deeply, finite element testing was repeated for five times in vertical load case. Results: The finite element analysis (FEA) data indicated that the NIN possessed the most outstanding mechanical properties among the three fixation models. The NIN model had lower maximal stress at implants compared to PFNA and InterTAN models under three load conditions. The trend of maximal stress at bones was similar to that of maximal stress at implants. Besides, the NIN model showed smaller maximal displacement compared with PFNA and InterTAN models under vertical, A-P bending, and torsional load cases. The trend for maximal displacement of fracture surface (MDFS) was almost identical with that of maximal displacement. In addition, there was significant difference between the PFNA and NIN groups in vertical load case (p < 0.05). Conclusion: Compared with PFNA and InterTAN, the NIN displayed the best mechanical properties for managing FIFs, including the lowest von Mises stress at implants and bones, and the smallest maximal displacement and MDFS under vertical, A-P bending, and torsional load cases. Therefore, this study might provide a new choice for patients with FIFs.

7.
Bioact Mater ; 37: 14-29, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38515610

RESUMO

Multi-drug resistant bacterial infections pose a significant threat to human health. Thus, the development of effective bactericidal strategies is a pressing concern. In this study, a ternary heterostructure (Zn-CN/P-GO/BiS) comprised of Zn-doped graphite phase carbon nitride (g-C3N4), phosphorous-doped graphene oxide (GO) and bismuth sulphide (Bi2S3) is constructed for efficiently treating methicillin-resistant Staphylococcus aureus (MRSA)-infected wound. Zn doping-induced defect sites in g-C3N4 results in a reduced band gap (ΔE) and a smaller energy gap (ΔEST) between the singlet state S1 and triplet state T1, which favours two-photon excitation and accelerates electron transfer. Furthermore, the formation of an internal electric field at the ternary heterogeneous interface optimizes the charge transfer pathway, inhibits the recombination of electron-hole pairs, improves the photodynamic effect of g-C3N4, and enhances its catalytic performance. Therefore, the Zn-CN/P-GO/BiS significantly augments the production of reactive oxygen species and heat under 808 nm NIR (0.67 W cm-2) irradiation, leading to the elimination of 99.60% ± 0.07% MRSA within 20 min. Additionally, the release of essential trace elements (Zn and P) promotes wound healing by activating hypoxia-inducible factor-1 (HIF-1) and peroxisome proliferator-activated receptors (PPAR) signaling pathways. This work provides unique insight into the rapid antibacterial applications of trace element doping and two-photon excitation.

8.
Small ; : e2312280, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38312094

RESUMO

Antibiotics are frequently used to clinically treat osteomyelitis caused by bacterial infections. However, extended antibiotic use may result in drug resistance, which can be life threatening. Here, a heterojunction comprising Fe2 O3 /Fe3 S4 magnetic composite is constructed to achieve short-term and efficient treat osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA). The Fe2 O3 /Fe3 S4 composite exhibits powerful microwave (MW) absorption properties, thereby effectively converting incident electromagnetic energy into thermal energy. Density functional theory calculations demonstrate that Fe2 O3 /Fe3 S4 possesses significant charge accumulation and oxygen-fixing capacity at the heterogeneous interface, which provides more active sites and oxygen sources for trapping electromagnetic hotspots. The finite element analysis indicates that Fe2 O3 /Fe3 S4 displays a larger electromagnetism field enhancement parameter than Fe2 O3 owing to a significant increase in electromagnetic hotspots. These hotspots contribute to charge differential accumulation and depletion motions at the interface, thereby augmenting the release of free electrons that subsequently combine with the oxygen adsorbed by Fe2 O3 /Fe3 S4 to generate reactive oxygen species (ROS) and heat. This research, which achieves extraordinary bacterial eradication through the synergistic effect of microwave thermal therapy (MWTT) and microwave dynamic therapy (MDT), presents a novel strategy for treating deep-tissue bacterial infections.

9.
Phys Chem Chem Phys ; 26(10): 8299-8307, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38389432

RESUMO

Considering that the hydrophobicity of PTAA as the surface of an inverted perovskite solar cell (PSC) substrate directly influences the crystallization and top surface properties of perovskite films, dual-interface engineering is a significant strategy to obtain excellent PSCs. PFN-Br was inserted into the PTAA/perovskite interface to ensure close interfacial contact and achieve exceptional crystallization, and then the perovskite top surface was covered with 3-PyAI to further improve its interface property. The mechanism of interaction of PFN-Br and 3-PyAI with perovskites was analyzed through various characterization methods. The results showed that the introduction of a hydrophilic interface layer reduces voids and defects at the bottom of the film. Additionally, the existence of 3-PyAI reduces surface defects, optimizes energy level alignment, and decreases non-radiative recombination, which is beneficial for charge transfer. Consequently, the open circuit voltage (VOC) and fill factor (FF) of the optimized device were greatly enhanced, and the champion device showed a power conversion efficiency (PCE) of 22.07%. The unencapsulated device with PFN-Br&3-PyAI can retain 80% of its initial performance after aging in the air atmosphere (25 °C at a relative humidity (RH) of 25%) for 27 days. Moreover, the reverse bias stability of the device was improved, with the reverse breakdown voltage (VRB) reaching -2 V. This work recommends a dual-interface strategy for efficient and reliable PTAA-based PSCs.

10.
PLoS One ; 19(1): e0296705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38261583

RESUMO

International trade has a significant impact on global environmental quality and sustainable economic development. Global value chains (GVCs) have become a crucial component of international trade and development policy. The global production structure has become more complicated with the inclusion of domestic markets in GVC, putting significant pressure on world energy resources and environmental sustainability. Therefore, traditional trade measures no longer accurately reflect how global trade affects the energy security of developing and developed countries. Thus, this study is the first to use a panel-corrected standard error method to look at the relationship between GVC participation and energy security by using a global sample of 35 developed and 27 developing nations from 1995 to 2018. A feasible generalized least squares model was also applied to confirm the robustness of the model. Six indicators-foreign direct investment, industrialization level, capital formation, human capital index, political stability, and GVC-were used in this research to look at their impact on the four fundamental pillars of energy security (availability, applicability, sustainability, and affordability) for sustainable economic development. For developed countries, it was confirmed that there is a non-linear relationship between GVC participation and energy intensity, renewable energy consumption, and non-fossil fuel use. In the case of developing countries, the non-linear relationship in terms of all aspects of energy security was also confirmed. The findings also indicated that GVC's involvement benefits all four dimensions of energy security in both developing and developed countries once it reaches a certain threshold. Our findings further support the impacts of long-term cointegration between GVC and energy security for sustainable economic development. Therefore, the nations must promote technology transfer and capacity building within GVCs for inclusive energy security. Similarly, they may foster sustainable practices through collaborative governance for a stable global energy network by acknowledging the positive impact of income levels on energy security.


Assuntos
Comércio , Internacionalidade , Humanos , Países Desenvolvidos , Junções Comunicantes , Desenvolvimento Econômico
11.
Cell Prolif ; 57(1): e13535, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37551727

RESUMO

Periodontal disease and arthroplasty prosthesis loosening and destabilization are both associated with osteolysis, which is predominantly caused by abnormal bone resorption triggered by pro-inflammatory cytokines. Osteoclasts (OCs) are critical players in the process. Concerns regarding the long-term efficacy and side effects of current frontline therapies, however, remain. Alternative therapies are still required. The aim of this work was to investigate the involvement of Tenacissoside H (TDH) in RANKL-mediated OC differentiation, as well as inflammatory osteolysis and associated processes. In vitro, bone marrow-derived macrophages (BMMs) cultured with RANKL and M-CSF were used to detect TDH in the differentiation and function of OCs. Real-time quantitative PCR was used to measure the expression of specific genes and inflammatory factors in OCs. Western blot was used to identify NFATc1, IKK, NF-κB, MAPK pathway, and oxidative stress-related components. Finally, an LPS-mediated calvarial osteolysis mouse model was employed to explore TDH's role in inflammatory osteolysis. The results showed that in vivo TDH inhibited the differentiation and resorption functions of OCs and down-regulated the transcription of osteoclast-specific genes, as well as Il-1ß, Il-6 and Tnf-α. In addition, TDH inhibited the IKK and NF-κB signalling pathways and down-regulated the level of ROS. In vivo studies revealed that TDH improves the bone loss caused by LPS. TDH may be a new candidate or treatment for osteoclast-associated inflammatory osteolytic disease.


Assuntos
Osteólise , Animais , Camundongos , Osteólise/induzido quimicamente , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Osteoclastos/metabolismo , Ligante RANK/metabolismo , Diferenciação Celular , Fatores de Transcrição NFATC/metabolismo
12.
Small ; 20(15): e2307406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009734

RESUMO

Osteomyelitis caused by deep tissue infections is difficult to cure through phototherapy due to the poor penetration depth of the light. Herein, Cu/C/Fe3O4-COOH nanorod composites (Cu/C/Fe3O4-COOH) with nanoscale tip convex structures are successfully fabricated as a microwave-responsive smart bacteria-capture-killing vector. Cu/C/Fe3O4-COOH exhibited excellent magnetic targeting and bacteria-capturing ability due to its magnetism and high selectivity affinity to the amino groups on the surface of Staphylococcus aureus (S. aureus). Under microwave irradiation, Cu/C/Fe3O4-COOH efficiently treated S. aureus-infected osteomyelitis through the synergistic effects of microwave thermal therapy, microwave dynamic therapy, and copper ion therapy. It is calculated the electric field intensity in various regions of Cu/C/Fe3O4-COOH under microwave irradiation, demonstrating that it obtained the highest electric field intensity on the surface of copper nanoparticles of Cu/C/Fe3O4-COOH due to its high-curvature tips and metallic properties. This led to copper nanoparticles attracted more charged particles compared with other areas in Cu/C/Fe3O4-COOH. These charges are easier to escape from the high curvature surface of Cu/C/Fe3O4-COOH, and captured by adsorbed oxygen, resulting in the generation of reactive oxygen species. The Cu/C/Fe3O4-COOH designed in this study is expected to provide insight into the treatment of deep tissue infections under the irradiation of microwave.


Assuntos
Nanopartículas , Osteomielite , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Cobre/química , Micro-Ondas/uso terapêutico , Nanopartículas/química , Infecções Estafilocócicas/terapia , Osteomielite/terapia
13.
Cytokine ; 173: 156436, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979214

RESUMO

Failure of bone healing after fracture often results in nonunion, but the underlying mechanism of nonunion pathogenesis is poorly understood. Herein, we provide evidence to clarify that the inflammatory microenvironment of atrophic nonunion (AN) mice suppresses the expression levels of DNA methyltransferases 2 (DNMT2) and 3A (DNMT3a), preventing the methylation of CpG islands on the promoters of C-terminal binding protein 1/2 (CtBP1/2) and resulting in their overexpression. Increased CtBP1/2 acts as transcriptional corepressors that, along with histone acetyltransferase p300 and Runt-related transcription factor 2 (Runx2), suppress the expression levels of six genes involved in bone healing: BGLAP (bone gamma-carboxyglutamate protein), ALPL (alkaline phosphatase), SPP1 (secreted phosphoprotein 1), COL1A1 (collagen 1a1), IBSP (integrin binding sialoprotein), and MMP13 (matrix metallopeptidase 13). We also observe a similar phenomenon in osteoblast cells treated with proinflammatory cytokines or treated with a DNMT inhibitor (5-azacytidine). Forced expression of DNMT2/3a or blockage of CtBP1/2 with their inhibitors can reverse the expression levels of BGLAP/ALPL/SPP1/COL1A1/IBSP/MMP13 in the presence of proinflammatory cytokines. Administration of CtBP1/2 inhibitors in fractured mice can prevent the incidence of AN. Thus, we demonstrate that the downregulation of bone healing genes dependent on proinflammatory cytokines/DNMT2/3a/CtBP1/2-p300-Runx2 axis signaling plays a critical role in the pathogenesis of AN. Disruption of this signaling may represent a new therapeutic strategy to prevent AN incidence after bone fracture.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core , Citocinas , DNA (Citosina-5-)-Metiltransferases , DNA Metiltransferase 3A , Consolidação da Fratura , Animais , Camundongos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Citocinas/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metiltransferases/metabolismo , Osteoblastos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Consolidação da Fratura/genética , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A/genética , DNA Metiltransferase 3A/metabolismo
14.
Sci Total Environ ; 912: 169354, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38104840

RESUMO

The oceanic-to-neritic species shift of microzooplanktonic tintinnids and their interaction with relevant abiotic variables are two crucial processes in the marine ecosystem. However, these processes remain poorly documented in China's marginal seas. In the summer of 2022, we investigated the community structure of pelagic tintinnids in surface waters from the South China Sea (SCS) to the Yellow Sea (YS), passing through the East China Sea (ECS). A number of 58 species from 23 genera were identified, with 36 and 22 species belonging to oceanic and neritic genera, respectively. The abundance proportion of oceanic and neritic genera exhibited a decreasing and increasing trend, respectively, from the SCS to YS. Furthermore, four distinctive tintinnid community groups were classified based on cluster analysis using tintinnid species and abundance data, and the position of southern Taiwan Strait was identified as the "Shift Point" for oceanic-to-neritic species dominance. The top two tintinnid species in each group showed distinct variations in body size. Additionally, multivariate biotic-abiotic statistical analyses revealed that temperature determined tintinnid species richness, while temperature, salinity, Si(OH)4, and Chl a determined tintinnid abundance. Our study provides a substantial foundation for recognizing the oceanic-to-neritic species shift of tintinnids in the China's marginal seas, and highlights the role of biotic-abiotic factors in driving biogeochemical fluxes and the potential response of microzooplankton to future climate change.


Assuntos
Cilióforos , Ecossistema , Oceanos e Mares , China , Estações do Ano
15.
J Transl Med ; 21(1): 839, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993937

RESUMO

BACKGROUND: Activated osteoclasts cause excessive bone resorption, and disrupt bone homeostasis, leading to osteoporosis. The extracellular signal-regulated kinase (ERK) signaling is the classical pathway related to osteoclast differentiation, and mitochondrial reactive oxygen species are closely associated with the differentiation of osteoclasts. Myrislignan (MRL), a natural product derived from nutmeg, has multiple pharmacological activities; however, its therapeutic effect on osteoporosis is unclear. Here, we investigated whether MRL could inhibit osteoclastogenesis and bone mass loss in an ovariectomy mouse model by suppressing mitochondrial function and ERK signaling. METHODS: Tartrate-resistant and phosphatase (TRAP) and bone resorption assays were performed to observe the effect of MRL on osteoclastogenesis of bone marrow macrophages. MitoSOX RED and tetramethyl rhodamine methyl ester (TMRM) staining was performed to evaluate the inhibitory effect of MRL on mitochondria. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was performed to detect whether MRL suppressed the expression of osteoclast-specific genes. The impact of MRL on the protein involved in the mitogen-activated protein kinase (MAPK) and nuclear factor-κB pathways was evaluated using western blotting. In addition, a specific ERK agonist LM22B-10, was used to revalidate the inhibitory effect of MRL on ERK. Finally, we established an ovariectomy mouse model to assess the therapeutic effect of MRL on osteoporosis in vivo. RESULTS: MRL inhibited osteoclast differentiation and the associated bone resorption, by significantly decreasing osteoclastic gene expression. Mechanistically, MRL inhibited the phosphorylation of ERK by suppressing the mitochondrial function, thereby downregulating the nuclear factor of activated T cells 1 (NFATc1) signaling. LM22B-10 treatment further verified the targeted inhibition effect of MRL on ERK. Microscopic computed tomographic and histologic analyses of the tibial tissue sections indicated that ovariectomized mice had lower bone mass and higher expression of ERK compared with normal controls. However, MRL treatment significantly reversed these effects, indicating the anti-osteoporosis effect of MRL. CONCLUSION: We report for the first time that MRL inhibits ERK signaling by suppressing mitochondrial function, thereby ameliorating ovariectomy-induced osteoporosis. Our findings can provide a basis for the development of a novel therapeutic strategy for osteoporosis.


Assuntos
Reabsorção Óssea , Osteoporose , Humanos , Feminino , Camundongos , Animais , Osteogênese , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Osteoclastos , Reabsorção Óssea/patologia , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , NF-kappa B/metabolismo , Diferenciação Celular , Ovariectomia , Ligante RANK/metabolismo
16.
Mar Pollut Bull ; 197: 115772, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37988968

RESUMO

Microbial food webs (MFW) play an indispensable role in marine pelagic ecosystem, yet their composition and response to abiotic variables were poorly documented in the oligotrophic tropical Western Pacific. During winter of 2015, we conducted a survey to examine key components of MFW, including Synechococcus, Prochlorococcus, picoeukaryotes, heterotrophic prokaryotes (HP), heterotrophic/pigmented nanoflagellates and ciliates, across water column from surface to 2000 m. Each MFW component exhibited unique vertical distribution pattern, with abundance ratio varying over six and three orders of magnitude across Pico/Microplankton (1.6 ± 1.0 × 106) and Nano/Microplankton (3.2 ± 2.8 × 103), respectively. Furthermore, HP was main component for MFW in the bathypelagic (>1000 m) zone. Multivariate biota-environment analysis demonstrated that environmental variables, particularly temperature, significantly impacted MFW composition, suggesting that bottom-up control (resource availability) dominated the water column. Our study provides benchmark information for future environmental dynamics forcing on MFW in the oligotrophic tropical seas.


Assuntos
Ecossistema , Cadeia Alimentar , Plâncton , Oceanos e Mares , Água
17.
Integr Cancer Ther ; 22: 15347354231198195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37694878

RESUMO

PURPOSE: This study was developed to evaluate the effects of moxibustion on tumor microenvironmental hypoxia in a murine model of Lewis lung carcinoma (LLC). METHODS: Twenty-four tumor-bearing mice were randomized into tumor group (T), tumor + cisplatin group (TC), tumor + moxibustion group (TM), and tumor + cisplatin + moxibustion group (TMC) (n = 6/group). Six age-matched C57BL/6 mice were employed as control group (Ctrl). A tumor model was established by implanting LLC cells into the right flank of each mouse. Animals in the TM group received moxibustion treatment at the ST36 (bilateral) and GV4 acupoints on the day of visible tumor formation. Moxibustion treatment was performed every other day for a total of 7 sessions. Animals in the TC group were intraperitoneally injected with cisplatin (3 mg/kg) on day 3 after visible tumor formation, and this treatment was performed every 3 days for 4 times. Animals in the TMC group underwent combined moxibustion and chemotherapy treatment, following the same conditions as outlined above. Following treatment, the concentrations of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), CD31, and Ki67 were measured using ELISA, Western blot, and immunohistochemical staining. RESULTS: Compared to the tumor group, treatment in the TM, TC, and TCM groups resulted in varying reductions in tumor growth (P < .001 or P < .05), while tumor microenvironmental hypoxia was alleviated as evidenced by the downregulation of HIF-1α, VEGFA, and CD31(P < .001-P < .05). CONCLUSION: Our results suggest that a combined approach of moxibustion and cisplatin can alleviate intratumoral hypoxia, promote vascular normalization, and slow the growth of LLC tumors in mice.


Assuntos
Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Moxibustão , Camundongos , Animais , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Camundongos Endogâmicos C57BL , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microambiente Tumoral , Hipóxia
18.
iScience ; 26(10): 107760, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37720109

RESUMO

Osteoporosis is a prevalent systemic metabolic disease in modern society, in which patients often suffer from bone loss due to over-activation of osteoclasts. Currently, amelioration of bone loss through modulation of osteoclast activity is a major therapeutic strategy. Ataxia telangiectasia mutated (ATM) inhibitor CGK733 (CG) was reported to have a sensitizing impact in treating malignancies. However, its effect on osteoporosis remains unclear. In this study, we investigated the effects of CG on osteoclast differentiation and function, as well as the therapeutic effects of CG on osteoporosis. Our study found that CG inhibits osteoclast differentiation and function. We further found that CG inhibits the activation of NFATc1 and ultimately osteoclast formation by inhibiting RANKL-mediated Ca2+ oscillation and the NF-κB/MAPK signaling pathway. Next, we constructed an ovariectomized mouse model and demonstrated that CG improved bone loss in ovariectomized mice. Therefore, CG may be a potential drug for the prevention and treatment of osteoporosis.

19.
Exp Cell Res ; 432(1): 113765, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37696386

RESUMO

Atrophic nonunion (AN) is a complex and poorly understood pathological condition resulting from impaired fracture healing. Advanced glycation end products (AGEs) have been implicated in the pathogenesis of several bone disorders, including osteoporosis and osteoarthritis. However, the role of AGEs in the development of AN remains unclear. This study found that mice fed a high-AGE diet had a higher incidence of atrophic nonunion (AN) compared to mice fed a normal diet following tibial fractures. AGEs induced two C-terminal binding proteins (CtBPs), CtBP1 and CtBP2, which were necessary for the development of AN in response to AGE accumulation. Feeding a high-AGE diet after fracture surgery in CtBP1/2-/- and RAGE-/- (receptor of AGE) mice did not result in a significant occurrence of AN. Molecular investigation revealed that CtBP1 and CtBP2 formed a heterodimer that was recruited by histone deacetylase 1 (HDAC1) and runt-related transcription factor 2 (Runx2) to assemble a complex. The CtBP1/2-HDAC1-Runx2 complex was responsible for the downregulation of two classes of bone development and differentiation genes, including bone morphogenic proteins (BMPs) and matrix metalloproteinases (MMPs). These findings demonstrate that AGE accumulation promotes the incidence of AN in a CtBP1/2-dependent manner, possibly by modulating genes related to bone development and fracture healing. These results provide new insights into the pathogenesis of AN and suggest new therapeutic targets for its prevention and treatment.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core , Fatores de Transcrição , Camundongos , Animais , Incidência , Produtos Finais de Glicação Avançada , Receptor para Produtos Finais de Glicação Avançada
20.
Cancer Biomark ; 38(2): 131-142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37599522

RESUMO

Cancer has become a leading cause of morbidity and mortality in recent years. Its high prevalence has had a severe impact on society. Researchers have achieved fruitful results in the causative factors, pathogenesis, treatment strategies, and cancer prevention. Semaphorin 3F (SEMA3F), a member of the signaling family, was initially reported in the literature to inhibit the growth, invasion, and metastasis of cancer cells in lung cancer. Later studies showed it has cancer-inhibiting effects in malignant tumors such as breast, colorectal, ovarian, oral squamous cell carcinoma, melanoma, and head and neck squamous carcinoma. In contrast, recent studies have reported that SEMA3F is expressed more in hepatocellular carcinoma than in normal tissue and promotes metastasis of hepatocellular carcinoma. We chose lung, breast, colorectal, and hepatocellular carcinomas with high clinical prevalence to review the roles and molecular mechanisms of SEMA3F in these four carcinomas. We concluded with an outlook on clinical interventions for patients targeting SEMA3F.


Assuntos
Carcinoma Hepatocelular , Carcinoma de Células Escamosas , Neoplasias Colorretais , Neoplasias de Cabeça e Pescoço , Neoplasias Hepáticas , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Proteínas de Membrana , Incidência , Proteínas do Tecido Nervoso , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Colorretais/patologia
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