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We analyze the role of the energy flow coefficient in beam shifts and develop the theory of the angle spectrum method to calculate the beam shifts of polarized beam reflection and transmission. By applying the self-consistency between the law of conservation of momentum and the angular Goos-Hänchen (GH) shift, we prove the necessity of the correcting energy flow coefficient of the transmitted light fields. For the air-glass interface, we find that the influence of the energy flow coefficient on the angular GH shift is very pronounced in the case of close grazing.
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Inflammatory bowel diseases (IBDs) are immune chronic diseases characterized by recurrent episodes, resulting in continuous intestinal barrier damage and intestinal microbiota dysbiosis. Safe strategies aimed at stabilizing and reducing IBDs recurrence have been vigorously pursued. Here, we constructed a recurrent intestinal injury Drosophila model and found that vitamin B12 (VB12), an essential co-factor for organism physiological functions, could effectively protect the intestine and reduce dextran sulfate sodium-induced intestinal barrier disruption. VB12 also alleviated microbial dysbiosis in the Drosophila model and inhibited the growth of gram-negative bacteria. We demonstrated that VB12 could mitigate intestinal damage by activating the hypoxia-inducible factor-1 signaling pathway in injured conditions, which was achieved by regulating the intestinal oxidation. In addition, we also validated the protective effect of VB12 in a murine acute colitis model. In summary, we offer new insights and implications for the potential supportive role of VB12 in the management of recurrent IBDs flare-ups.
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Sulfato de Dextrana , Modelos Animais de Doenças , Microbioma Gastrointestinal , Fator 1 Induzível por Hipóxia , Mucosa Intestinal , Transdução de Sinais , Vitamina B 12 , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Vitamina B 12/farmacologia , Vitamina B 12/metabolismo , Camundongos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Transdução de Sinais/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Fator 1 Induzível por Hipóxia/metabolismo , Colite/metabolismo , Colite/induzido quimicamente , Colite/microbiologia , Colite/patologia , Colite/tratamento farmacológico , Disbiose/microbiologia , Disbiose/metabolismo , Camundongos Endogâmicos C57BL , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Drosophila/metabolismoRESUMO
Hepatitis B virus (HBV) exploits the endosomal sorting complexes required for transport (ESCRT)/multivesicular body (MVB) pathway for virion budding. In addition to enveloped virions, HBV-replicating cells nonlytically release non-enveloped (naked) capsids independent of the integral ESCRT machinery, but the exact secretory mechanism remains elusive. Here, we provide more detailed information about the existence and characteristics of naked capsid, as well as the viral and host regulations of naked capsid egress. HBV capsid/core protein has two highly conserved Lysine residues (K7/K96) that potentially undergo various types of posttranslational modifications for subsequent biological events. Mutagenesis study revealed that the K96 residue is critical for naked capsid egress, and the intracellular egress-competent capsids are associated with ubiquitinated host proteins. Consistent with a previous report, the ESCRT-III-binding protein Alix and its Bro1 domain are required for naked capsid secretion through binding to intracellular capsid, and we further found that the ubiquitinated Alix binds to wild type capsid but not K96R mutant. Moreover, screening of NEDD4 E3 ubiquitin ligase family members revealed that AIP4 stimulates the release of naked capsid, which relies on AIP4 protein integrity and E3 ligase activity. We further demonstrated that AIP4 interacts with Alix and promotes its ubiquitination, and AIP4 is essential for Alix-mediated naked capsid secretion. However, the Bro1 domain of Alix is non-ubiquitinated, indicating that Alix ubiquitination is not absolutely required for AIP4-induced naked capsid secretion. Taken together, our study sheds new light on the mechanism of HBV naked capsid egress in viral life cycle.
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Capsídeo , Vírus da Hepatite B , Ubiquitina-Proteína Ligases Nedd4 , Ubiquitina-Proteína Ligases , Liberação de Vírus , Humanos , Proteínas de Ligação ao Cálcio , Capsídeo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Hepatite B/metabolismo , Hepatite B/virologia , Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Vírus da Hepatite B/genética , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Liberação de Vírus/fisiologiaRESUMO
Copper, a vital mineral nutrient, possesses redox qualities that make it both beneficial and toxic to organisms. Excessive environmental copper exposure can result in neurological damage and cognitive decline in humans. Astrocytes, the predominant glial cells in the brain, are particularly vulnerable to pollutants, but the mechanism of copper-induced damage to astrocytes remains elusive. The aim of this study was to determine the role of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway in initiating NLRP3 inflammasome-induced astrocyte pyroptosis and chronic inflammation under conditions of copper overload. Our findings indicated that copper exposure elevated mitochondrial ROS (mtROS) levels, resulting in mitochondrial damage in astrocytes. This damage caused the release of mitochondrial DNA (mtDNA) into the cytoplasm, which subsequently activated the cGAS-STING pathway. This activation resulted in interactions between STING and NLRP3 proteins, facilitating the assembly of the NLRP3 inflammasome and inducing pyroptosis. Furthermore, depletion of mtROS mitigated copper-induced mitochondrial damage in astrocytes and reduced mtDNA leakage. Pharmacological inhibition of STING or STING transfection further reversed copper-induced pyroptosis and the inflammatory response. In conclusion, this study demonstrated that the leakage of mtDNA into the cytoplasm and the subsequent activation of the cGAS-STING-NLRP3 pathway may be potential mechanisms underlying copper-induced pyroptosis in astrocytes. These findings provided new insights into the toxicity of copper.
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Chronic hepatitis B virus (HBV) infection remains a significant public health burden with no cure currently available. The research to cure HBV has long been hampered by the lack of immunocompetent small animal models capable of supporting HBV infection. Here, we set out to explore the feasibility of the golden Syrian hamster as an immunocompetent small rodent model for HBV infection. We first started with in vitro assessments of the HBV replication cycle in primary hamster hepatocytes (PHaHs) by adenoviral HBV (Ad-HBV) transduction. Our results demonstrated that PHaHs support HBV reverse transcription and subsequent cccDNA formation via the intracellular recycling pathway. Next, with luciferase reporter assays, we confirmed that PHaHs support the activities of all HBV major promoters. Then, we transduced PHaHs with an adenoviral vector expressing HBV receptor human Na+/taurocholate cotransporting polypeptide NTCP (Ad-huNTCP), followed by HBV inoculation. While the untransduced PHaHs did not support HBV infection, Ad-huNTCP-transduced PHaHs supported de novo cccDNA formation, viral mRNA transcription, and expression of viral antigens. We then humanized the amino acid (aa) residues of hamster NTCP (haNTCP) critical for HBV entry, aa84-87 and aa157-165, and transfected HepG2 cells with constructs expressing wild-type haNTCP and humanized-haNTCP, H84R/P87N and H84R/P87N/G157K/M160V/M165L, respectively, followed by HBV inoculation. The results showed that the humanization of H84R/P87N alone was sufficient to support HBV infection at a level comparable to that supported by huNTCP. Taken together, the above in vitro evidence supports the future direction of humanizing haNTCP for HBV infection in vivo.IMPORTANCEOne of the biggest challenges in developing an HBV cure is the lack of immunocompetent animal models susceptible to HBV infection. Developing such models in mice has been unsuccessful due to the absence of a functional HBV receptor, human NTCP (huNTCP), and the defect in supporting viral cccDNA formation. In search of alternative models, we report herein multiple lines of in vitro evidence for developing a golden Syrian hamster model for HBV infection. We demonstrate that the primary hamster hepatocytes (PHaHs) support HBV replication, transcription, and cccDNA formation, and PHaHs are susceptible to de novo HBV infection in the presence of huNTCP. Furthermore, expressing hamster NTCP with two humanized residues critical for HBV entry renders HepG2 cells permissive to HBV infection. Thus, our work lays a solid foundation for establishing a gene-edited hamster model that expresses humanized NTCP for HBV infection in vivo.
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Expanding the application field of polyolefin materials through functionalization has been a research hotspot in the past three decades. Here, a TiO2-supported anilinenaphthoquinone nickel catalyst was assembled and applied for in situ ethylene polymerization with high activity (>2000 kg mol-1h-1) to produce ultra-high molecular weight polyethylene (UHMWPE)/TiO2 composites with unique physicochemical performance. The UHMWPE/TiO2 composite films and fibers prepared by in-situ ethylene polymerization are superior to the samples from the blend system in issues such as TiO2 dispersibility, mechanical property, and photocatalytic degradability. The mechanical properties (strength up to 26.8 cN/dtex, modulus up to 1248.8 cN/dtex) of the obtained UHMWPE/TiO2 composite fibers are significantly improved with a very low dosage of TiO2 (as low as 1.4 wt). Moreover, UHMWPE/TiO2 composites obtained by coating Al2O3 and SiO2 on the surface of TiO2 not only retain the strong absorption of ultraviolet rays, but also effectively weaken the photocatalytic degradation effect.
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Spiking neural networks (SNNs), known for their low-power, event-driven computation, and intrinsic temporal dynamics, are emerging as promising solutions for processing dynamic, asynchronous signals from event-based sensors. Despite their potential, SNNs face challenges in training and architectural design, resulting in limited performance in challenging event-based dense prediction tasks compared with artificial neural networks (ANNs). In this work, we develop an efficient spiking encoder-decoder network (SpikingEDN) for large-scale event-based semantic segmentation (EbSS) tasks. To enhance the learning efficiency from dynamic event streams, we harness the adaptive threshold which improves network accuracy, sparsity, and robustness in streaming inference. Moreover, we develop a dual-path spiking spatially adaptive modulation (SSAM) module, which is specifically tailored to enhance the representation of sparse events and multimodal inputs, thereby considerably improving network performance. Our SpikingEDN attains a mean intersection over union (MIoU) of 72.57% on the DDD17 dataset and 58.32% on the larger DSEC-Semantic dataset, showing competitive results to the state-of-the-art ANNs while requiring substantially fewer computational resources. Our results shed light on the untapped potential of SNNs in event-based vision applications. The source codes are publicly available at https://github.com/EMI-Group/spikingedn.
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BACKGROUND: Psychological problems affect economic development. However, there is a huge gap between mental health service resources and mental health service needs. Existing mental health service technology and platforms cannot meet all the diverse mental health needs of people. Smart medicine is a new medical system based online that can effectively improve the quality and efficiency of medical services and make mental health services accessible. AIM: To explore the level of intelligent medical use among young and middle-aged people and its correlation with psychological factors. METHODS: Convenience sampling was used to select 200 young and middle-aged patients with medical experience at the Third People's Hospital of Chengdu between January 2022 and January 2023 as the research subjects. The general condition Questionnaire, Eysenck Personality Questionnaire, Symptom Checklist-90, General Health Questionnaire, and Smart Medical Service Use Intention Questionnaire were used to collect data. Pearson's correlation was used to analyze the correlation between the participants' willingness to use smart medical services and their personality characteristics, psychological symptoms, and mental health. RESULTS: The results revealed that the mental health of young and middle-aged people was poor, and some had psychological problems such as anxiety, depression, and physical discomfort. Familiarity, acceptance, and usage of smart healthcare in this population are at a medium level, and these levels correlate with psychological characteristics. Acceptance was positively correlated with E, and negatively correlated with P, anxiety, fear, anxiety/insomnia, and social dysfunction. The degree of use was negatively correlated with P, obsessive-compulsive symptoms, depression, anxiety, hostility, paranoia, and somatic symptoms. CONCLUSION: The familiarity, acceptance, and usage of smart medical services among the middle-aged and young groups are related to various psychological characteristics.
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The gut microbiota is a complex and diverse community of microorganisms that colonizes the human gastrointestinal tract and influences various aspects of human health. These microbes are closely related to enteric infections. As a foreign entity for the host, commensal microbiota is restricted and regulated by the barrier and immune system in the gut and contributes to gut homeostasis. Commensals also effectively resist the colonization of pathogens and the overgrowth of indigenous pathobionts by utilizing a variety of mechanisms, while pathogens have developed strategies to subvert colonization resistance. Dysbiosis of the microbial community can lead to enteric infections. The microbiota acts as a pivotal mediator in establishing a harmonious mutualistic symbiosis with the host and shielding the host against pathogens. This review aims to provide a comprehensive overview of the mechanisms underlying host-microbiome and microbiome-pathogen interactions, highlighting the multi-faceted roles of the gut microbiota in preventing enteric infections. We also discuss the applications of manipulating the microbiota to treat infectious diseases in the gut.
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The introduction of anti-tumor necrosis factor α (TNFα) biologics significantly innovated inflammatory bowel disease (IBD) treatment and increased medical costs. The recent expiration of patents of some anti-TNFα biologics (such as infliximab and adalimumab) facilitated the development of biosimilars. Comparable pharmacokinetic, efficacy, safety, and immunogenicity profiles between anti-TNFα originators and biosimilars were demonstrated in different studies. Anti-TNFα biosimilars hold promise for reducing the high cost of biologics and increasing patient access to biologics. In this review, we outline the current data on the use of anti-TNFα originators and biosimilars in patients with IBD, with a focus on the efficacy, safety, and immunogenicity profiles of infliximab and adalimumab biosimilars. The potential benefits, challenges, and future directions of anti-TNFα biosimilars are also discussed in the review.
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2D ferroelectric materials have attracted extensive research interest due to potential applications in nonvolatile memory, nanoelectronics and optoelectronics. However, the available 2D ferroelectric materials are scarce and most of them are limited by the uncontrollable preparation. Herein, a novel 2D ferroelectric material AgCrS2 is reported that are controllably synthesized in large-scale via salt-assist chemical vapor deposition growth. By tuning the growth temperature from 800 to 900 °C, the thickness of AgCrS2 nanosheets can be precisely modulated from 2.1 to 40 nm. Structural and nonlinear optical characterizations demonstrate that AgCrS2 nanosheet crystallizes in a non-centrosymmetric structure with high crystallinity and remarkable air stability. As a result, AgCrS2 of various thicknesses display robust ferroelectric polarization in both in-plane (IP) and out-of-plane (OOP) directions with strong intercorrelation and high ferroelectric phase transition temperature (682 K). Theoretical calculations suggest that the ferroelectricity in AgCrS2 originates from the displacement of Ag atoms in AgS4 tetrahedrons, which changes the dipole moment alignment. Moreover, ferroelectric switching is demonstrated in both lateral and vertical AgCrS2 devices, which exhibit exotic nonvolatile memory behavior with distinct high and low resistance states. This study expands the scope of 2D ferroelectric materials and facilitates the ferroelectric-based nonvolatile memory applications.
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Drought stress significantly affects the growth, development, and yield of cotton, triggering the response of multiple genes. Among them, ascorbate peroxidase (APX) is one of the important antioxidant enzymes in the metabolism of reactive oxygen species in plants, and APX enhances the ability of plants to resist oxidation, thus increasing plant stress tolerance. Therefore, enhancing the activity of APX in cells is crucial to improving plant stress resistance. Previous studies have isolated differentially expressed proteins under drought stress (GhAPX7) in drought-resistant (KK1543) and drought-sensitive (XLZ26) plants. Thus, this study analyzed the expression patterns of GhAPX7 in different cotton tissues to verify the drought resistance function of GhAPX7 and explore its regulatory pathways. GhAPX7 had the highest expression in cotton leaves, which significantly increased under drought stress, suggesting that GhAPX7 is essential for improving antioxidant capacity and enzyme activities in cotton. GhAPX7 silencing indirectly affects pronounced leaf yellowing and wilting in drought-resistant and drought-sensitive plants under drought stress. Malondialdehyde (MDA) content was significantly increased and chlorophyll and proline content and APX enzyme activity were generally decreased in silenced plants compared to the control. This result indicates that GhAPX7 may improve drought resistance by influencing the contents of MDA, chlorophyll, proline, and APX enzyme activity through increased expression levels. Transcriptome analysis revealed that the drought-related differentially expressed genes between the control and treated groups enriched plant hormone signal transduction, MAPK signaling, and plant-pathogen interaction pathways. Therefore, the decreased expression of GhAPX7 significantly affects the expression levels of genes in these three pathways, reducing drought resistance in plants. This study provides insights into the molecular mechanisms of GhAPX7 and its role in drought resistance and lays a foundation for further research on the molecular mechanisms of response to drought stress in cotton.
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BACKGROUND: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer (BC). TNBC has a poor prognosis due to high intratumoral heterogeneity and metastasis, pointing to the need to explore distinct molecular subtypes and gene regulatory networks. METHODS: The scRNA-seq data of five primary BC samples were downloaded from the Gene Expression Omnibus (GEO) database. Clustering was performed based on filtered and normalized data using the Seurat R package to identify marker genes, which were subsequently annotated to each subset using the CellMarker database. AUCell R package was applied to calculate the hallmark score for each epithelial cell. Marker genes of each subset were screened with FindAllMarkers and their biological functions were analyzed using the Database for Annotation Visualization and Integrated Discovery (DAVID) database. Next, cell-cell communication was performed with the CellChat R package. To identify the key regulatory genes, single-cell regulatory network inference and clustering (SCENIC) analysis was conducted. Finally, the expression and potential biological functions of the key regulatory factors were verified through cellular experiments. RESULTS: A total of 29,101 cells were classified into nine cell subsets, namely, Fibroblasts, Fibroepithelial cells, Epithelial cells 1, Epithelial cells 2, Epithelial cells 3, Endothelial cells, T cells, Plasma B cells and Macrophages. Particularly, the epithelial cells had a higher proportion and higher transforming growth factor-ß (TGF-ß) activity in the TNBC pathotype as compared to the non-TNBC pathotype. Furthermore, four epithelial cell subsets (marked as Stearoyl-CoA Desaturase (SCD1), marker of proliferation Ki67 (MKI67), Annexin A3 (ANXA3) and aquaporin 5 (AQP5)) were identified as having the greatest impact on the TNBC pathotype. Cell-cell interaction analysis revealed that ANXA3-epithelial cell subset suppressed the T cell function through different mechanisms. C-fos gene (FOS) and X-box binding protein 1 (XBP1) were considered critical regulons involved in TNBC progression. Notably, cellular experiments demonstrated that silencing XBP1 and overexpressing FOS inhibited cancer cell invasion. CONCLUSION: The four epithelial cell subsets and two critical regulons identified based on the scRNA-seq data could help explore the underlying intratumoral heterogeneity molecular mechanism and develop effective therapies for TNBC.
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Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Análise de Célula Única , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Humanos , Análise de Célula Única/métodos , Feminino , Análise de Sequência de RNA/métodos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Comunicação Celular/genética , Heterogeneidade Genética , Perfilação da Expressão Gênica/métodosRESUMO
Cobalt has the highest Curie temperature (Tc) among the elemental ferromagnetic metals and has a hexagonal close-packed (HCP) structure at room temperature. In this study, HCP Co was thinned to the thickness of several (n) unit cells along the c-axis and then passivated by halogen atoms, thus being named Co2nX2 (X = F, Cl, Br and I). For Co2X2 and Co3X2, all of them are not only kinetically but also thermodynamically stable from the viewpoint of the phonon spectra and molecular dynamics. Similar to HCP Co, two-dimensional (2D) Co2F2, Co2Cl2 and Co3X2 (X = Cl, Br and I) are still ferromagnetic metals within the Stoner model but Co2X2 (X = Br and I) is a ferromagnetic half-metal with the coexistence of the metallic behavior for one spin and the insulating behavior for the other spin. Taking into account the spin-orbital coupling (SOC), the easy-magnetization axis is within the plane where the magnetization is isotropic, making it look like a 2D XY magnet. Applying a critical biaxial strain could lead to an easy-magnetization axis changing from the in-plane to the out-of-plane direction. Finally, we use classical Monte Carlo simulations to estimate the Curie temperature (Tc) which is as high as 957 and 510 K for Co2F2 and Co2Cl2, respectively, because of the strong direct exchange interaction. Different from being obtained by mechanical or liquid exfoliation from van der Waals layered structures, our study opens up new possibilities to search for novel 2D ferromagnets from the elemental ferromagnets and provides opportunities for realizing realistic ultra-thin spintronic devices.
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The popularization of intelligent toys enriches the lives of the general public. To provide the public with a better toy experience, we propose the intelligent toy tracking method by the mobile cloud terminal deployment and depth-first search algorithm. Firstly, we construct a toy detection model via Transformer, which realizes the positioning of toys in the image through the refined region adaptive boundary representation. Then, using these detected continuous frames, we improve the toy tracking based on a depth-first search. Long-short-term memory (LSTM) constructs the continuous frame tracking structure, and the depth-first search mechanism is embedded to realize the accurate tracking of multiple targets in continuous frames. Finally, to realize the terminal marginalization of the proposed method, this chapter proposes a lightweight model deployment method based on mobile cloud terminals to realize the maintenance of the optimal machine state of intelligent toys. The experiment proves that our proposed target method can reach the world-leading level and obtain the mAP value of 0.858. Our tracking method can also perform excellently with a MOTA value of 0.916.
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We report two previously undiscovered phases of GeTe including the sphalerite (c-) phase and the hexagonal (h-) phase with interlayer van der Waals gaps. A polymorphic phase transformation from rhombohedral α-GeTe to c- and h-GeTe at near room temperature is first realized via electron beam irradiation. Their underlying thermodynamics and kinetics are illustrated using the in situ heating experiments and molecular dynamics simulations. Density-functional theory calculations indicate that c-GeTe exhibits typical metallic behavior and h-GeTe is a narrow-gap semiconductor with a strong spin-orbital coupling effect. Our findings shed light on a strategy for designing GeTe-based quantum devices compromising nanopillars and heterostructures via an atomic-scale electron beam lithography technique.
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BACKGROUND: To evaluate the effectiveness of a sequential internal fixation strategy and intramedullary nailing with plate augmentation (IMN/PA) for bone reconstruction in the management of infected femoral shaft defects using the Masquelet technique. METHODS: We performed a retrospective descriptive cohort study of 21 patients (mean age, 36.4 years) with infected bone defects of the femoral shaft treated by the Masquelet technique with a minimum follow-up of 18 months after second stage. After aggressive debridement, temporary stabilisation (T1) was achieved by an antibiotic-loaded bone cement spacer and internal fixation with a bone cement-coated locking plate. At second stage (T2), the spacer and the locking plate were removed following re-debridement, and IMN/PA was used as definitive fixation together with bone grafting. We evaluated the following clinical outcomes: infection recurrence, bone union time, complications, and the affected limb's knee joint function. RESULTS: The median and quartiles of bone defect length was 7 (4.75-9.5) cm. Four patients required iterative debridement for infection recurrence after T1. The median of interval between T1 and T2 was 10 (9-19) weeks. At a median follow-up of 22 (20-27.5) months, none of the patients experienced recurrence of infection. Bone union was achieved at 7 (6-8.5) months in all patients, with one patient experiencing delayed union at the distal end of bone defect due to screws loosening. At the last follow-up, the median of flexion ROM of the knee joint was 120 (105-120.0)°. CONCLUSIONS: For infected femoral shaft bone defects treated by the Masquelet technique, sequential internal fixation and IMN/PA for the reconstruction can provide excellent mechanical stability, which is beneficial for early functional exercise and bone union, and does not increase the rate of infection recurrence.
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Pinos Ortopédicos , Placas Ósseas , Desbridamento , Fraturas do Fêmur , Fixação Intramedular de Fraturas , Humanos , Masculino , Estudos Retrospectivos , Feminino , Adulto , Fraturas do Fêmur/cirurgia , Pessoa de Meia-Idade , Desbridamento/métodos , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/instrumentação , Adulto Jovem , Resultado do Tratamento , Transplante Ósseo/métodos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Seguimentos , Cimentos Ósseos/uso terapêutico , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Fêmur/cirurgia , AdolescenteRESUMO
Despite the well-documentation of the effects of straw returning on soil structural stability and fertility, its long-term in situ impacts on profile aggregate size composition and organic carbon (OC) fractions remain poorly investigated. To address this research gap, the present nine-year field trial explored the co-effects of straw returning and chemical fertilization on soil total OC (TOC), dissolved OC (DOC), resistant OC (ROC), easily oxidative OC (EOC), as well as soil aggregate size composition of different soil depths (0-15, 15-30, and 30-50 cm) in a paddy field, East China. To do so, four different treatments were set up, including no straw returning plus no fertilization (CK), conventional fertilization (F), straw returning plus conventional fertilization (SF), and straw returning plus 80 % conventional fertilization (SDF). Our findings revealed that the >2 mm aggregates were dominant in all treatments, particularly in SF and SDF 0-30 cm soil layers ranging from 62 to 70 % (P < 0.05). The highest TOC contents happened in SF topsoil 0.25-2 mm aggregates (0-30 cm; 21.4 g/kg), 44.4 and 21.1 % higher than the CK and F treatments, respectively (P < 0.05). Regardless of soil depth, the highest EOC contents occurred in SDF 0.25-2 mm aggregates varying from 2.36 ± 0.1 to 7.7 ± 0.57 g/kg (P < 0.05). Further, the highest ROC and DOC contents took place in SF 0.25-2 mm and SF > 2 mm aggregates, respectively, differing from 3.86 to 15.8 g/kg and 250-413 mg/kg, respectively (P < 0.05). It is also worth noting that SF had the highest crop productivity with the seasonal yields of 3.51 and 13.5 t ha-1 for rapeseed and rice, respectively (P < 0.05). Altogether, our findings suggested that long-term straw returning coupled with conventional (SF) or 80 % conventional (SDF) fertilization are the most efficient schemes for the formation/stability of soil aggregates, as well as for the accumulation of different soil OC fractions and crop productivity in the Chaohu Lake agricultural soils of East China.
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As human activities continue to expand, wildlife persistence faces escalating threats from roads. In Wolong area of Giant Panda National Park, the local giant pandas (Ailuropoda melanoleuca) are divided into two population groups along the National Highway G350 (NHG). Therefore, selecting suitable areas to help those giant pandas communicate across the NHG is necessary. In this research, we evaluated the presence of human activities and simulated their absence to analyze how they affect the giant panda's habitat in Wolong. Subsequently, based on the kernel density estimation (KDE) for giant pandas and the main human distribution locations, we selected suitable areas for the population link between the two road sections on the NHG. We simulated the absence of human activities on the two road sections to compare changes in the habitat suitability index (HSI) and connectivity value (CV) relative to their presence. We aimed to carefully select the area for future giant panda corridor plans and simulate whether eliminating human activities will significantly improve the HSI and CV of the area. Our results show that: (1) Human activities presence has led to subtle changes in the landscape pattern of suitable habitats and a decrease in Wolong by 78.76 km2 compared to their absence. (2) Human activities presence significantly reduced HSI and CV in the 1000 m buffer along the NHG compared to their absence. (3) The HSI and CV of the 1000 m buffer in the simulated absence of human activities for the two road sections were significantly higher than their presence. This research identified the optimal road section for crossing the NHG to link giant panda population groups and habitats in Wolong. These insights are significant for formulating conservation decisions and corridor plans and for promoting wildlife conservation in reserves amid high levels of human activity.
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Climate change can pose a significant threat to terrestrial ecosystems by disrupting the circulation of soil nitrogen. However, experimental analyses on the effect of climate change on soil nitrogen cycles and the implications for the conservation of key wildlife species (i.e., the giant panda, Ailuropoda melanoleuca) remain understudied. We investigated the effects of a 1.5 °C, 3 °C, and 4.5 °C temperature increase on nitrogen distribution in different soil layers of bamboo forest via an in-situ experiment and assessed the implications for the growth and survival of arrow bamboo (Bashania faberi), a critical food resource for giant pandas. Our results showed that warming treatments generally increased soil N content, while effects differed between surface soil and subsurface soil and at different warming treatments. Particularly an increase of 1.5 °C raised the subsurface soil NO3-N content, as well as the content of N in bamboo leaves. We found a significant positive correlation between the subsurface soil NO3-N content and the N content of arrow bamboo. An increase of 3-4.5 °C raised the content of total N and NO3-N in the surface soil and led to a reduction in the total aboveground biomass and survival rate of arrow bamboo. Limited warming (e.g., the increase of 0-1.5 °C) may promote the soil N cycle, raise the N-acetylglucosaminidase (NAG) enzyme activity, increase NO3-N in subsurface soil, increase the N content of bamboo, and boost the biomass of bamboo - all of which could be beneficial to giant panda survival. However, higher warming (e.g., an increase of 3-4.5 °C) resulted in mass death of bamboo and a large reduction in aboveground biomass. Our findings provide a cautiously optimistic scenario for bamboo forest ecosystems under low levels of warming over a short period of time, but risks from higher levels of warming may be serious, especially considering the unpredictability of global climatic change.