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1.
Sci Data ; 11(1): 487, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734679

RESUMO

Radiation therapy (RT) is a crucial treatment for head and neck squamous cell carcinoma (HNSCC); however, it can have adverse effects on patients' long-term function and quality of life. Biomarkers that can predict tumor response to RT are being explored to personalize treatment and improve outcomes. While tissue and blood biomarkers have limitations, imaging biomarkers derived from magnetic resonance imaging (MRI) offer detailed information. The integration of MRI and a linear accelerator in the MR-Linac system allows for MR-guided radiation therapy (MRgRT), offering precise visualization and treatment delivery. This data descriptor offers a valuable repository for weekly intra-treatment diffusion-weighted imaging (DWI) data obtained from head and neck cancer patients. By analyzing the sequential DWI changes and their correlation with treatment response, as well as oncological and survival outcomes, the study provides valuable insights into the clinical implications of DWI in HNSCC.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia Guiada por Imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Aceleradores de Partículas
2.
Artigo em Inglês | MEDLINE | ID: mdl-38709608

RESUMO

The joint clustering of multimodal remote sensing (RS) data poses a critical and challenging task in Earth observation. Although recent advances in multiview subspace clustering have shown remarkable success, existing methods become computationally prohibitive when dealing with large-scale RS datasets. Moreover, they neglect intrinsic nonlinear and spatial interdependencies among heterogeneous RS data and lack generalization ability for out-of-sample data, thereby restricting their applicability. This article introduces a novel unified framework called anchor-based multiview kernel subspace clustering with spatial regularization (AMKSC). It learns a scalable anchor graph in the kernel space, leveraging contributions from each modality instead of seeking a consensus full graph in the feature space. To ensure spatial consistency, we incorporate a spatial smoothing operation into the formulation. The method is efficiently solved using an alternating optimization strategy, and we provide theoretical evidence of its scalability with linear computational complexity. Furthermore, an out-of-sample extension of AMKSC based on multiview collaborative representation-based classification is introduced, enabling the handling of larger datasets and unseen instances. Extensive experiments on three real heterogeneous RS datasets confirm the superiority of our proposed approach over state-of-the-art methods in terms of clustering performance and time efficiency. The source code is available at https://github.com/AngryCai/AMKSC.

3.
Virol J ; 21(1): 87, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641833

RESUMO

BACKGROUND: Bovine parvovirus (BPV) is an autonomous DNA virus with a smaller molecular size and subtle differences in its structural proteins, unlike other animal parvoviruses. More importantly, this virus has the potential to produce visible to silent economic catastrophes in the livestock business, despite receiving very little attention. Parvoviral virus-like particles (VLPs) as vaccines and as logistical platforms for vaccine deployment are well studied. However, no single experimental report on the role of VP1 in the assembly and stability of BPV-VLPs is available. Furthermore, the self-assembly, integrity and stability of the VLPs of recombinant BPV VP2 in comparison to VP1 VP2 Cap proteins using any expression method has not been studied previously. In this study, we experimentally evaluated the self-assembling ability with which BPV virus-like particles (VLPs) could be synthesized from a single structural protein (VP2) and by integrating both VP2 and VP1 amino acid sequences. METHODS: In silico and experimental cloning methods were carried out. His-tagged and without-His-tag VP2 and V1VP2-encoding amino acid sequences were cloned and inserted into pFastbacdual, and insect cell-generated recombinant protein was evaluated by SDS‒PAGE and western blot. Period of infectivity and expression level were determined by IFA. The integrity and stability of the BPV VLPs were evaluated by transmission electron microscopy. The secondary structure of the BPV VLPs from both VP2 and V1VP2 was analyzed by circular dichroism. RESULTS: Our findings show that VP2 alone was equally expressed and purified into detectable proteins, and the stability at different temperatures and pH values was not appreciably different between the two kinds of VLPs. Furthermore, BPV-VP2 VLPs were praised for their greater purity and integrity than BPV-VP1VP2 VLPs, as indicated by SDS‒PAGE. Therefore, our research demonstrates that the function of VP1 has no bearing on the stability or integrity of BPV-VLPs. CONCLUSIONS: In summary, incredible physiochemically stable BPV VP2-derived VLPs have been found to be promising candidates for the development of multivalent vaccines and immunodiagnostic kits against enteric viruses and to carry heterogeneous epitopes for various economically important livestock diseases.


Assuntos
Bocavirus , Parvovirus , Vacinas , Animais , Baculoviridae/genética , Proteínas Recombinantes/genética , Proteínas do Capsídeo/genética
4.
Zhongguo Zhong Yao Za Zhi ; 49(4): 932-941, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621900

RESUMO

This study explored the biosynthesis of bufadienolides(BDs) in Bufo bufo gargarizans to solve the dilemma of the decreasing resources of B. bufo gargarizans and provide a theoretical basis for the sustainable utilization of the resources. Ultra-high performance liquid chromatography-Orbitrap-mass spectrometry(UHPLC-Orbitrap-MS) was employed to detect the synthesis sites of BDs in B. bufo gargarizans, and the results were verified by desorption electrospray ionization-mass spectrometry imaging(DESI-MSI) and homogenate incubation experiments. BDs in B. bufo gargarizans had the highest content in the liver and the highest concentration in the gallbladder, in addition to the parotid gland and skin, which suggested that the liver could synthesize BDs. The results of DESI-MSI also showed that BDs were mainly enriched in the liver rather than the immature parotid gland. The incubation experiment of liver homogenates demonstrated the liver of B. bufo gargarizans had the ability to synthesize BDs. This study showed that the liver was a major organ for the synthesis of BDs in B. bufo gargarizans during metamorphosis, development, and growth, which provided strong theoretical support for the biosynthesis of BDs and the sustainable utilization of B. bufo gargarizans resources.


Assuntos
Bufanolídeos , Animais , Bufo bufo , Distribuição Tecidual , Bufonidae , Espectrometria de Massas por Ionização por Electrospray
5.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1295-1309, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621977

RESUMO

The aim of this study was to explore the mechanism of icaritin-induced ferroptosis in hepatoma HepG2 cells. By bioinformatics screening, the target of icariin's intervention in liver cancer ferroptosis was selected, the protein-protein interaction(PPI) network was constructed, the related pathways were focused, the binding ability of icariin and target protein was evaluated by molecular docking, and the impact on patients' survival prognosis was predicted and the clinical prediction model was built. CCK-8, EdU, and clonal formation assays were used to detect cell viability and cell proliferation; colorimetric method and BODIPY 581/591 C1 fluorescent probe were used to detect the levels of Fe~(2+), MDA and GSH in cells, and the ability of icariin to induce HCC cell ferroptosis was evaluated; RT-qPCR and Western blot detection were used to verify the mRNA and protein levels of GPX4, xCT, PPARG, and FABP4 to determine the expression changes of these ferroptosis-related genes in response to icariin. Six intervention targets(AR, AURKA, PPARG, AKR1C3, ALB, NQO1) identified through bioinformatic analysis were used to establish a risk scoring system that aids in estimating the survival prognosis of HCC patients. In conjunction with patient age and TNM staging, a comprehensive Nomogram clinical prediction model was developed to forecast the 1-, 3-, and 5-year survival of HCC patients. Experimental results revealed that icariin effectively inhibited the activity and proliferation of HCC cells HepG2, significantly modulating levels of Fe~(2+), MDA, and lipid peroxidation ROS while reducing GSH levels, hence revealing its potential to induce ferroptosis in HCC cells. Icariin was found to diminish the expression of GPX4 and xCT(P<0.01), inducing ferroptosis in HCC cells, potentially in relation to inhibition of PPARG and FABP4(P<0.01). In summary, icariin induces ferroptosis in HCC cells via the PPARG/FABP4/GPX4 pathway, providing an experimental foundation for utilizing the traditional Chinese medicine icariin in the prevention or treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Flavonoides , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , PPAR gama , Células Hep G2 , Modelos Estatísticos , Simulação de Acoplamento Molecular , Prognóstico , Proteínas de Ligação a Ácido Graxo
6.
J Colloid Interface Sci ; 665: 240-251, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38531271

RESUMO

Seawater electrolysis to generate hydrogen offers a clean, green, and sustainable solution for new energy. However, the catalytic activity and durability of anodic catalysts are plagued by the corrosion and competitive oxidation reactions of chloride in high concentrations. In this study, we find that the additive CrO42- anions in the electrolyte can not only promote the formation and stabilization of the metal oxyhydroxide active phase but also greatly mitigate the adverse effect of Cl- on the anode. Linear sweep voltammetry, accelerated corrosion experiments, corrosion polarization curves, and charge transfer resistance results indicate that the addition of CrO42- distinctly improves oxygen evolution reaction (OER) kinetics and corrosion resistance in alkaline seawater electrolytes. Especially, the introduction of CrO42- even in the highly concentrated NaCl (2.5 M) electrolyte prolongs the durability of NiFe-LDH to almost five times the case without CrO42-. Density functional theory calculations also reveal that the adsorption of CrO42- can tune the electronic configuration of active sites of metal oxyhydroxides, enhance conductivity, and optimize the intermediate adsorption energies. This anionic additive strategy can give a better enlightenment for the development of efficient and stable oxygen evolution reactions for seawater electrolysis.

7.
Comput Med Imaging Graph ; 113: 102353, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38387114

RESUMO

Creating synthetic CT (sCT) from magnetic resonance (MR) images enables MR-based treatment planning in radiation therapy. However, the MR images used for MR-guided adaptive planning are often truncated in the boundary regions due to the limited field of view and the need for sequence optimization. Consequently, the sCT generated from these truncated MR images lacks complete anatomic information, leading to dose calculation error for MR-based adaptive planning. We propose a novel structure-completion generative adversarial network (SC-GAN) to generate sCT with full anatomic details from the truncated MR images. To enable anatomy compensation, we expand input channels of the CT generator by including a body mask and introduce a truncation loss between sCT and real CT. The body mask for each patient was automatically created from the simulation CT scans and transformed to daily MR images by rigid registration as another input for our SC-GAN in addition to the MR images. The truncation loss was constructed by implementing either an auto-segmentor or an edge detector to penalize the difference in body outlines between sCT and real CT. The experimental results show that our SC-GAN achieved much improved accuracy of sCT generation in both truncated and untruncated regions compared to the original cycleGAN and conditional GAN methods.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Simulação por Computador
8.
mBio ; 15(3): e0335823, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38303107

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a global pandemic, which severely endangers public health. Our and others' works have shown that the angiotensin-converting enzyme 2 (ACE2)-containing exosomes (ACE2-exos) have superior antiviral efficacies, especially in response to emerging variants. However, the mechanisms of how the virus counteracts the host and regulates ACE2-exos remain unclear. Here, we identified that SARS-CoV-2 nonstructural protein 6 (NSP6) inhibits the production of ACE2-exos by affecting the protein level of ACE2 as well as tetraspanin-CD63 which is a key factor for exosome biogenesis. We further found that the protein stability of CD63 and ACE2 is maintained by the deubiquitination of proteasome 26S subunit, non-ATPase 12 (PSMD12). NSP6 interacts with PSMD12 and counteracts its function, consequently promoting the degradation of CD63 and ACE2. As a result, NSP6 diminishes the antiviral efficacy of ACE2-exos and facilitates the virus to infect healthy bystander cells. Overall, our study provides a valuable target for the discovery of promising drugs for the treatment of coronavirus disease 2019. IMPORTANCE: The outbreak of coronavirus disease 2019 (COVID-19) severely endangers global public health. The efficacy of vaccines and antibodies declined with the rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutants. Angiotensin-converting enzyme 2-containing exosomes (ACE2-exos) therapy exhibits a broad neutralizing activity, which could be used against various viral mutations. Our study here revealed that SARS-CoV-2 nonstructural protein 6 inhibited the production of ACE2-exos, thereby promoting viral infection to the adjacent bystander cells. The identification of a new target for blocking SARS-CoV-2 depends on fully understanding the virus-host interaction networks. Our study sheds light on the mechanism by which the virus resists the host exosome defenses, which would facilitate the study and design of ACE2-exos-based therapeutics for COVID-19.


Assuntos
COVID-19 , Exossomos , Humanos , COVID-19/metabolismo , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Exossomos/metabolismo , Peptidil Dipeptidase A/metabolismo , Antivirais/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Ligação Proteica
9.
Colloids Surf B Biointerfaces ; 234: 113737, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176336

RESUMO

Titanium (Ti) and titanium alloy are the most common metal materials in clinical orthopedic surgery. However, in the initial stage of surgery and implantation, the production of excessive reactive oxygen species (ROS) can induce oxidative stress (OS) microenvironment. OS will further inhibit the growth of new bone, resulting in surgical failure. In this study, based on the fact that nanoscale manganese dioxide (MnO2) can show H2O2-like enzyme activity, a MnO2 nanocoating was prepared on mciro-nano structured surface of Ti substrate via a two-step method of alkaline thermal and hydrothermal treatment. The results of scanning electron microscopy (SEM), X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS) showed that the nano-MnO2 coating was successfully fabricated on the surface of Ti substrate. The results of measurement of H2O2, dissolved O2 and intracellular ROS in vitro showed that the treated Ti substrate could efficiently eliminate H2O2 and reduce ROS. Furthermore, the modified Ti substrate could promote the early adhesion, proliferation and osteogenic differentiation of MSCs, which was demonstrated by experimental results of cell morphology, cell viability, alkaline phosphatase, collagen, and mineralization deposition. The results of quantitative real-time polymerase chain reaction (qRT-PCR) of MSCs adhered the modified Ti substrate showed that the expression of genes related to osteogenic differentiation significantly increased. More importantly, the modified Ti implant could eliminate ROS at the injury site, reduce OS and promote the regeneration of bone tissue, which was demonstrated via hematoxylin/eosin, Masson's trichrome and immunohistochemical staining. In conclusion, the modified Ti implant presented here had the effect of reducing OS and promoting osseointegration. Relevant research ideas and results provide new methods for the research and development of functional implants, which have potential application value in the field of orthopedics.


Assuntos
Osteogênese , Titânio , Titânio/farmacologia , Titânio/química , Compostos de Manganês/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Óxidos/farmacologia , Peróxido de Hidrogênio/farmacologia , Osseointegração , Propriedades de Superfície
10.
Neurobiol Dis ; 191: 106409, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218457

RESUMO

Interictal epileptiform discharges (IEDs) often co-occur across spatially-separated cortical regions, forming IED networks. However, the factors prompting IED propagation remain unelucidated. We hypothesized that slow oscillations (SOs) might facilitate IED propagation. Here, the amplitude and phase synchronization of SOs preceding propagating and non-propagating IEDs were compared in 22 patients with focal epilepsy undergoing intracranial electroencephalography (EEG) evaluation. Intracranial channels were categorized into the irritative zone (IZ) and normal zone (NOZ) regarding the presence of IEDs. During wakefulness, we found that pre-IED SOs within the IZ exhibited higher amplitudes for propagating IEDs than non-propagating IEDs (delta band: p = 0.001, theta band: p < 0.001). This increase in SOs was also concurrently observed in the NOZ (delta band: p = 0.04). Similarly, the inter-channel phase synchronization of SOs prior to propagating IEDs was higher than those preceding non-propagating IEDs in the IZ (delta band: p = 0.04). Through sliding window analysis, we observed that SOs preceding propagating IEDs progressively increased in amplitude and phase synchronization, while those preceding non-propagating IEDs remained relatively stable. Significant differences in amplitude occurred approximately 1150 ms before IEDs. During non-rapid eye movement (NREM) sleep, SOs on scalp recordings also showed higher amplitudes before intracranial propagating IEDs than before non-propagating IEDs (delta band: p = 0.006). Furthermore, the analysis of IED density around sleep SOs revealed that only high-amplitude sleep SOs demonstrated correlation with IED propagation. Overall, our study highlights that transient but widely distributed SOs are associated with IED propagation as well as generation in focal epilepsy during sleep and wakefulness, providing new insight into the EEG substrate supporting IED networks.


Assuntos
Eletroencefalografia , Epilepsias Parciais , Humanos , Sono , Eletrocorticografia , Vigília
11.
ACS Omega ; 9(1): 942-954, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222560

RESUMO

To understand the effects of additives on the performance of a Ni-Co-P alloy electroplated coating, this study, based on a single-factor experiment, utilized a Box-Behnken experimental design to optimize an additive that can enhance the electrodeposited Ni-Co-P alloy coating's properties, including hardness, glossiness, and corrosion resistance. The study used tools such as a gloss meter, a Vickers hardness tester, and an electrochemical workstation to analyze the impact of different additives on the coating's hardness and gloss. The optimal additive combination was determined. The results from the Box-Behnken experiment showed that when the concentrations of sodium dodecyl sulfate, thiourea, and sodium allyl sulfonate reached 0.10, 0.15, and 0.22 g/L, respectively, the resulting coating hardness was 475.4 HV0.5, and the gloss level was 463.4 GU. Compared to the coatings without additives, the hardness increased by 90.34 HV0.5, and the glossiness rose by 101.2 GU. The coating's corrosion resistance also improved. This enhancement is attributed to the compounded additive, which significantly improved the surface morphology of the coating, making it smoother and more compact. The morphology and composition of the coatings with additives were analyzed through scanning electron microscopy and energy dispersive X-ray spectroscopy, and the composition of the coating contains 71.01 at % Ni, 20.65 at % Co, and 8.34 at % P. At the same time, the optimized coating exhibits a metallic luster similar to stainless steel, meeting industrial requirements.

12.
Ann Clin Transl Neurol ; 11(2): 414-423, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38059543

RESUMO

OBJECTIVES: To investigate and characterize epileptic seizures and electrophysiological features of familial cortical myoclonic tremor with epilepsy (FCMTE) type 1 patients in a large Chinese cohort. METHODS: We systematically evaluated 125 FCMTEtype 1 patients carrying the pentanucleotide (TTTCA) repeat expansion in the SAMD12 gene in China. RESULTS: Among the 28 probands, epileptic seizures (96.4%, 27/28) were the most common reason for an initial clinic visit. Ninety-seven (77.6%, 97/125) patients had experienced seizures. The seizures onset age was 36.5 ± 9.0 years, which was 6.9 years later than cortical tremors. The seizures were largely rare (<1/year, 58.8%) and occasional (1-6/year, 37.1%). Prolonged prodromes were reported in 57.7% (56/97). Thirty-one patients (24.8%, 31/125) reported photosensitivity history, and 79.5% (31/39) had a photoparoxysmal response. Interictal epileptiform discharges (IEDs) were recorded in 69.1% (56/81) of patients. Thirty-three patients showed generalized IEDs and 72.7% (24/33) were occipitally dominant, while 23 patients presented with focal IEDs with 65.2% (15/23) taking place over the occipital lobe. Overnight EEG of FCMTE patients displayed paradoxical sleep-wake fluctuation, with a higher average IED index of 0.82 ± 0.88/min during wakefulness and a lower IED index of 0.04 ± 0.06/min during non-rapid eye movement sleep stages I-II. INTERPRETATION: FCMTE type 1 has a benign course of epilepsy and distinct clinical and electrophysiological features. In addition to a positive family history and cortical myoclonus tremor, the seizure prodromes, specific seizure triggers, photosensitivity, distribution of IEDs, and unique fluctuations during sleep-wake cycle are cues for proper genetic testing and an early diagnosis of FCMTE.


Assuntos
Epilepsias Mioclônicas , Epilepsia , Humanos , Adulto , Pessoa de Meia-Idade , Tremor/genética , Epilepsias Mioclônicas/genética , Convulsões
13.
J Med Virol ; 95(12): e29300, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38063070

RESUMO

Little is known about antibody responses to natural Omicron infection and the risk factors for poor responders in patients with hematological malignancies (HM). We conducted a multicenter, prospective cohort study during the latest Omicron wave in Chongqing, China, aiming to compare the antibody responses, as assessed by IgG levels of anti-receptor binding domain of spike protein (anti-S-RBD), to Omicron infection in the HM cohort (HMC) with healthy control cohort (HCC), and solid cancer cohort (SCC). In addition, we intend to explore the risk factors for poor responders in the HMC. Among the 466 HM patients in this cohort, the seroconversion rate was 92.7%, no statistically difference compared with HCC (98.2%, p = 0.0513) or SCC (100%, p = 0.1363). The median anti-S-RBD IgG titer was 29.9 ng/mL, significantly lower than that of HCC (46.9 ng/mL, p < 0.0001) or SCC (46.2 ng/mL, p < 0.0001). Risk factors associated with nonseroconversion included no COVID-19 vaccination history (odds ratio [OR] = 4.58, 95% confidence interval [CI]: 1.75-12.00, p = 0.002), clinical course of COVID-19 ≤ 7 days (OR = 2.86, 95% CI: 1.31-6.25, p = 0.008) and severe B-cell reduction (0-10/µL) (OR = 3.22, 95% CI: 1.32-7.88, p = 0.010). Risk factors associated with low anti-S-RBD IgG titer were clinical course of COVID-19 ≤ 7 days (OR = 2.58, 95% CI: 1.59-4.18, p < 0.001) and severe B-cell reduction (0-10/µL) (OR = 2.87, 95% CI: 1.57-5.24, p < 0.001). This study reveals a poor antibody responses to Omicron (BA.5.2.48) infection in HM patients and identified risk factors for poor responders. Highlights that HM patients, especially those with these risk factors, may be susceptible to SARS-CoV-2 reinfection, and the postinfection vaccination strategies for these patients should be tailored. Clinical trial: ChiCTR2300071830.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , Formação de Anticorpos , SARS-CoV-2 , Estudos Prospectivos , Neoplasias Hematológicas/complicações , Progressão da Doença , Imunoglobulina G , Anticorpos Antivirais
14.
ACS Nano ; 17(22): 22885-22900, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37947356

RESUMO

Stem cell senescence is one of the most representative events of organism aging and is responsible for many physiological abnormalities and disorders. In the scenario of orthopedic disease treatment, stem cell aging may affect the implantation outcome and even lead to operation failure. To explore whether stem cell aging will affect the osteointegration effect of titanium implant, a widely used micronano titanium (MNT) was fabricated. We first verified the expected osteointegration effect of the MNT, which could be attributed to the improvement of stem cell adhesion and osteogenic differentiation. Then, we obtained aged-derived bone marrow mesenchymal stem cells (BMSCs) and studied their biological behaviors on MNT both in vitro and in vivo. We found that compared with normal rats, MNT did not significantly improve the osteointegration in aged rats. Compared with normal rats, fewer endogenous stem cells were observed at the implant-host interface, and the expression of p21 (senescence marker) was also higher. We further confirmed that MNT promoted the nuclear localization of NF-κB in senescent stem cells through the activation of p38 MAPK, thereby inducing the occurrence of the senescence-associated secretory phenotype (SASP) and ultimately leading to the depletion of the stem-cell pool at the implant-host interface. However, the activation of p38 MAPK can still promote the osteogenic differentiation of nonsenescent BMSCs. These results showed an interesting paradoxical balance between osteogenesis and senescence on MNT surfaces and also provided insights for the design of orthopedic implants for aging patients.


Assuntos
Células-Tronco Mesenquimais , Titânio , Ratos , Humanos , Animais , Idoso , Titânio/farmacologia , Titânio/metabolismo , Fenótipo Secretor Associado à Senescência , Osteogênese , Diferenciação Celular , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologia , Células Cultivadas
15.
J Med Imaging (Bellingham) ; 10(6): 065501, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37937259

RESUMO

Purpose: To improve segmentation accuracy in head and neck cancer (HNC) radiotherapy treatment planning for the 1.5T hybrid magnetic resonance imaging/linear accelerator (MR-Linac), three-dimensional (3D), T2-weighted, fat-suppressed magnetic resonance imaging sequences were developed and optimized. Approach: After initial testing, spectral attenuated inversion recovery (SPAIR) was chosen as the fat suppression technique. Five candidate SPAIR sequences and a nonsuppressed, T2-weighted sequence were acquired for five HNC patients using a 1.5T MR-Linac. MR physicists identified persistent artifacts in two of the SPAIR sequences, so the remaining three SPAIR sequences were further analyzed. The gross primary tumor volume, metastatic lymph nodes, parotid glands, and pterygoid muscles were delineated using five segmentors. A robust image quality analysis platform was developed to objectively score the SPAIR sequences on the basis of qualitative and quantitative metrics. Results: Sequences were analyzed for the signal-to-noise ratio and the contrast-to-noise ratio and compared with fat and muscle, conspicuity, pairwise distance metrics, and segmentor assessments. In this analysis, the nonsuppressed sequence was inferior to each of the SPAIR sequences for the primary tumor, lymph nodes, and parotid glands, but it was superior for the pterygoid muscles. The SPAIR sequence that received the highest combined score among the analysis categories was recommended to Unity MR-Linac users for HNC radiotherapy treatment planning. Conclusions: Our study led to two developments: an optimized, 3D, T2-weighted, fat-suppressed sequence that can be disseminated to Unity MR-Linac users and a robust image quality analysis pathway that can be used to objectively score SPAIR sequences and can be customized and generalized to any image quality optimization protocol. Improved segmentation accuracy with the proposed SPAIR sequence will potentially lead to improved treatment outcomes and reduced toxicity for patients by maximizing the target coverage and minimizing the radiation exposure of organs at risk.

16.
Science ; 381(6662): eabn4180, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676964

RESUMO

Despite substantial advances in targeting mutant KRAS, tumor resistance to KRAS inhibitors (KRASi) remains a major barrier to progress. Here, we report proteostasis reprogramming as a key convergence point of multiple KRASi-resistance mechanisms. Inactivation of oncogenic KRAS down-regulated both the heat shock response and the inositol-requiring enzyme 1α (IRE1α) branch of the unfolded protein response, causing severe proteostasis disturbances. However, IRE1α was selectively reactivated in an ER stress-independent manner in acquired KRASi-resistant tumors, restoring proteostasis. Oncogenic KRAS promoted IRE1α protein stability through extracellular signal-regulated kinase (ERK)-dependent phosphorylation of IRE1α, leading to IRE1α disassociation from 3-hydroxy-3-methylglutaryl reductase degradation (HRD1) E3-ligase. In KRASi-resistant tumors, both reactivated ERK and hyperactivated AKT restored IRE1α phosphorylation and stability. Suppression of IRE1α overcame resistance to KRASi. This study reveals a druggable mechanism that leads to proteostasis reprogramming and facilitates KRASi resistance.


Assuntos
Antineoplásicos , Resistencia a Medicamentos Antineoplásicos , Endorribonucleases , Inibidores Enzimáticos , MAP Quinases Reguladas por Sinal Extracelular , Fatores de Transcrição de Choque Térmico , Neoplasias , Proteostase , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Inibidores Enzimáticos/farmacologia , Antineoplásicos/farmacologia , Fatores de Transcrição de Choque Térmico/metabolismo
17.
Epilepsy Behav ; 147: 109387, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37625346

RESUMO

Coronavirus disease-2019 (COVID-19) first emerged in late 2019 and has since spread worldwide. More than 600 million people have been diagnosed with COVID-19, and over 6 million have died. Vaccination against COVID-19 is one of the best ways to protect humans. Epilepsy is a common disease, and there are approximately 10 million patients with epilepsy (PWE) in China. However, China has listed "uncontrolled epilepsy" as a contraindication for COVID-19 vaccination, which makes many PWE reluctant to get COVID-19 vaccination, greatly affecting the health of these patients in the COVID-19 epidemic. However, recent clinical practice has shown that although a small percentage of PWE may experience an increased frequency of seizures after COVID-19 vaccination, the benefits of COVID-19 vaccination for PWE far outweigh the risks, suggesting that COVID-19 vaccination is safe and recommended for PWE. Nonetheless, vaccination strategies vary for different PWE, and this consensus provides specific recommendations for PWE to be vaccinated against COVID-19.


Assuntos
COVID-19 , Epilepsia , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Consenso , População do Leste Asiático , Epilepsia/complicações , Epilepsia/epidemiologia , Vacinação
18.
medRxiv ; 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37645931

RESUMO

Radiation therapy (RT) is a crucial treatment for head and neck squamous cell carcinoma (HNSCC), however it can have adverse effects on patients' long-term function and quality of life. Biomarkers that can predict tumor response to RT are being explored to personalize treatment and improve outcomes. While tissue and blood biomarkers have limitations, imaging biomarkers derived from magnetic resonance imaging (MRI) offer detailed information. The integration of MRI and a linear accelerator in the MR-Linac system allows for MR-guided radiation therapy (MRgRT), offering precise visualization and treatment delivery. This data descriptor offers a valuable repository for weekly intra-treatment diffusion-weighted imaging (DWI) data obtained from head and neck cancer patients. By analyzing the sequential DWI changes and their correlation with treatment response, as well as oncological and survival outcomes, the study provides valuable insights into the clinical implications of DWI in HNSCC. [Table: see text].

19.
Epilepsy Behav ; 145: 109344, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37459719

RESUMO

BACKGROUND AND PURPOSE: In light of the ongoing COVID-19 pandemic, vaccination has emerged as the primary and most effective solution. The aim of this study was to examine compliance rates of vaccination and explore the factors that predict vaccine uptake among patients with epilepsy (PWE) who have undergone resection surgery. METHOD: To examine the variations in vaccination coverage, safety concerns, and factors influencing vaccination hesitancy among PWE who have undergone resection surgery, this study recruited patients with at least one-year follow-up. We utilized questionnaires to gather clinical characteristics and obtain information regarding COVID-19 vaccines. RESULTS: Among the 303 patients included in the study, a majority of 229 (75.58%) achieved a seizure-free outcome (Engel Ia). Of these patients, 178 (58.75%) received at least one dose of COVID-19 vaccine, and the vaccination rate has remained relatively consistent over the past six months. Nearly 94.95% of those who received the vaccine completed the full vaccination regimen, with the majority (n = 174, 97.75%) opting for an inactivated vaccine. Only three patients reported side effects unrelated to epilepsy, and one patient experienced a worsening of typical aura seizures within one month after vaccination. Notably, significant positive associations were observed between COVID-19 vaccine acceptance and adulthood (age 18 years or older) (OR = 1.820, 95% CI = 1.018-3.252, p = 0.043) as well as achieving a seizure-free outcome (OR = 2.823, 95% CI = 1.619-4.921, p < 0.001). Regarding the unvaccinated patients, approximately one-fifth expressed willingness to receive a future COVID-19 vaccine, while the remainder were hesitant (41.60%) or unsure (39.20%) about vaccination. These reservations mainly stemmed from concerns about the potential worsening of seizures and vaccine safety. CONCLUSIONS: Inactivated vaccines can be considered safe for individuals with epilepsy who have undergone resection surgery. The likelihood of being vaccinated was found to be comparatively higher among the cohort with seizure-free status or adults. To promote COVID-19 vaccination among children, it is crucial to implement comprehensive education and public awareness campaigns that emphasize the safety of vaccines. These efforts will help encourage widespread acceptance of vaccination and ensure the well-being of individuals with epilepsy.


Assuntos
COVID-19 , Epilepsias Parciais , Adolescente , Adulto , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Pandemias , Prevalência , Convulsões , Vacinação/efeitos adversos
20.
J Thorac Dis ; 15(6): 3386-3396, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37426170

RESUMO

Background: Postoperative venous thromboembolism (VTE) is a well-documented cause of morbidity and mortality in lung cancer patients. However, risk identification remains limited. In this study, we sought to analyze the risk factors for VTE and verify the predictive value of the modified Caprini risk assessment model (RAM). Methods: This prospective single-center study included patients with resectable lung cancer who underwent resection between October 2019 and March 2021. The incidence of VTE was estimated. Logistic regression was used to analyze the risk factors for VTE. Receiver operating characteristic (ROC) curve analysis was performed to test the ability of the modified Caprini RAM to predict VTE. Results: The VTE incidence was 10.5%. Several variables, including age, D-dimer, hemoglobin (Hb), bleeding, and patient confinement to bed were significantly associated with VTE after surgery. The difference between the VTE and non-VTE groups in the high-risk levels was statistically significant (P<0.001), while the low and moderate risk levels showed no significant difference. The combined use of the modified Caprini score and the Hb and D-dimer levels showed an area under the curve (AUC) was 0.822 [95% confidence interval (CI): 0.760-0.855. P<0.001]. Conclusions: The risk-stratification approach of the modified Caprini RAM is not particularly valid after lung resection in our population. The use of the modified Caprini RAM combined with Hb and D-dimer levels shows a good diagnostic performance for VTE prediction in patients with lung cancer undergoing resection.

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