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2.
Br J Cancer ; 130(10): 1621-1634, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38575732

RESUMO

BACKGROUND: DNA double-strand break (DSB) induction and repair are important events for determining cell survival and the outcome of cancer radiotherapy. The DNA-dependent protein kinase (DNA-PK) complex functions at the apex of DSBs repair, and its assembly and activity are strictly regulated by post-translation modifications (PTMs)-associated interactions. However, the PTMs of the catalytic subunit DNA-PKcs and how they affect DNA-PKcs's functions are not fully understood. METHODS: Mass spectrometry analyses were performed to identify the crotonylation sites of DNA-PKcs in response to γ-ray irradiation. Co-immunoprecipitation (Co-IP), western blotting, in vitro crotonylation assays, laser microirradiation assays, in vitro DNA binding assays, in vitro DNA-PK assembly assays and IF assays were employed to confirm the crotonylation, identify the crotonylase and decrotonylase, and elucidate how crotonylation regulates the activity and function of DNA-PKcs. Subcutaneous xenografts of human HeLa GCN5 WT or HeLa GCN5 siRNA cells in BALB/c nude mice were generated and utilized to assess tumor proliferation in vivo after radiotherapy. RESULTS: Here, we reveal that K525 is an important site of DNA-PKcs for crotonylation, and whose level is sharply increased by irradiation. The histone acetyltransferase GCN5 functions as the crotonylase for K525-Kcr, while HDAC3 serves as its dedicated decrotonylase. K525 crotonylation enhances DNA binding activity of DNA-PKcs, and facilitates assembly of the DNA-PK complex. Furthermore, GCN5-mediated K525 crotonylation is indispensable for DNA-PKcs autophosphorylation and the repair of double-strand breaks in the NHEJ pathway. GCN5 suppression significantly sensitizes xenograft tumors of mice to radiotherapy. CONCLUSIONS: Our study defines K525 crotonylation of DNA-PKcs is important for the DNA-PK complex assembly and DSBs repair activity via NHEJ pathway. Targeting GCN5-mediated K525 Kcr of DNA-PKcs may be a promising therapeutic strategy for improving the outcome of cancer radiotherapy.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteína Quinase Ativada por DNA , Camundongos Endogâmicos BALB C , Tolerância a Radiação , Fatores de Transcrição de p300-CBP , Humanos , Animais , Proteína Quinase Ativada por DNA/metabolismo , Camundongos , Fatores de Transcrição de p300-CBP/metabolismo , Células HeLa , Camundongos Nus , Feminino , Processamento de Proteína Pós-Traducional , Neoplasias/radioterapia , Neoplasias/metabolismo , Neoplasias/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Phys Eng Sci Med ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647634

RESUMO

We proposed a deep learning approach to classify various error types in daily VMAT treatment of head and neck cancer patients based on EPID dosimetry, which could provide additional information to support clinical decisions for adaptive planning. 146 arcs from 42 head and neck patients were analyzed. Anatomical changes and setup errors were simulated in 17,820 EPID images of 99 arcs obtained from 30 patients using in-house software for model training, validation, and testing. Subsequently, 141 clinical EPID images from 47 arcs belonging to the remaining 12 patients were utilized for clinical testing. The hierarchical convolutional neural network (HCNN) model was trained to classify error types and magnitudes using EPID dose difference maps. Gamma analysis with 3%/2 mm (dose difference/distance to agreement) criteria was also performed. The F1 score, a combination of precision and recall, was utilized to evaluate the performance of the HCNN model and gamma analysis. The adaptive fractioned doses were calculated to verify the HCNN classification results. For error type identification, the overall F1 score of the HCNN model was 0.99 and 0.91 for primary type and subtype identification, respectively. For error magnitude identification, the overall F1 score in the simulation dataset was 0.96 and 0.70 for the HCNN model and gamma analysis, respectively; while the overall F1 score in the clinical dataset was 0.79 and 0.20 for the HCNN model and gamma analysis, respectively. The HCNN model-based EPID dosimetry can identify changes in patient transmission doses and distinguish the treatment error category, which could potentially provide information for head and neck cancer treatment adaption.

4.
Heliyon ; 10(7): e27681, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38590877

RESUMO

Background: Chronic Rhinosinusitis is a common disease in children. The main function of CFTR is to maintain the thickness of the mucous layer on the surface of the nasal mucosa. CFTR disease-causing variant can cause CFTR protein dysfunction and induce or aggravate chronic infection. However, the carrying status of the CFTR variants in the Chinese population is not clear. Objective: To study the frequency and variants of CFTR in Chinese children with CRS and to analyze the CFTR variants and the clinical characteristics and susceptibility to CRS. Methods: Whole Exome Sequencing was performed to analyze the CFTR genes in a total of 106 CRS children from the Chinese mainland area. The CFTR variants, frequency and clinical data were summarized and analyzed. Results: A total of 31 CFTR variants were detected, of which the carrying rate of 7 sites was significantly higher than that of the population database. 88 patients carried more than 2 variants. 37 people carried variants (MAF < 0.05), of which 91.89% had a history of recurrent upper respiratory infections, 16 had nasal polyps, 5 had bronchiectasis, and 1 was diagnosed with CF-related disorders. Conclusion: The carrying rate of CFTR variants in Chinese CRS children increased, and the highest rates of variants (MAF < 0.05) are p.I556V, p. E217G, c.1210-12[T]. Carrying multiple CFTR variants, especially p.E217G, p.I807 M, p.V920L and c.1210-12[T] may lead to increased susceptibility to CRS. There are CF-related disorders in patients with CRS.

5.
Cell Death Dis ; 15(3): 209, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480704

RESUMO

Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring radiation resistance to tumor cells. How radiation changes the glycolysis status of cancer cells is still unclear. Here we revealed the role of TAB182 in regulating glycolysis and lactate production in cellular response to ionizing radiation. Irradiation can significantly stimulate the production of TAB182 protein, and inhibiting TAB182 increases cellular radiosensitivity. Proteomic analysis indicated that TAB182 influences several vital biological processes, including multiple metabolic pathways. Knockdown of TAB182 results in decreased lactate production and increased pyruvate and ATP levels in cancer cells. Moreover, knocking down TAB182 reverses radiation-induced metabolic changes, such as radioresistant-related lactate production. TAB182 is necessary for activating LDHA transcription by affecting transcription factors SP1 and c-MYC; its knockdown attenuates the upregulation of LDHA by radiation, subsequently suppressing lactate production. Targeted suppression of TAB182 significantly enhances the sensitivity of murine xenograft tumors to radiotherapy. These findings advance our understanding of glycolytic metabolism regulation in response to ionizing radiation, which may offer significant implications for developing new strategies to overcome tumor radioresistance.


Assuntos
L-Lactato Desidrogenase , Proteômica , Humanos , Animais , Camundongos , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5/metabolismo , Linhagem Celular Tumoral , Glicólise , Lactatos , Tolerância a Radiação/genética
6.
J Gen Virol ; 105(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506716

RESUMO

PCV2 belongs to the genus Circovirus in the family Circoviridae, whose genome is replicated by rolling circle replication (RCR). PCV2 Rep is a multifunctional enzyme that performs essential functions at multiple stages of viral replication. Rep is responsible for nicking and ligating single-stranded DNA and unwinding double-stranded DNA (dsDNA). However, the structure and function of the Rep are still poorly understood, which significantly impedes viral replication research. This study successfully resolved the structure of the PCV2 Rep ATPase domain (PRAD) using X-ray crystallography. Homologous structure search revealed that Rep belonged to the superfamily 3 (SF3) helicase, and multiple conserved residues were identified during sequence alignment with SF3 family members. Simultaneously, a hexameric PRAD model was generated for analysing characteristic structures and sites. Mutation of the conserved site and measurement of its activity showed that the hallmark motifs of the SF3 family influenced helicase activity by affecting ATPase activity and ß-hairpin just caused the loss of helicase activity. The structural and functional analyses of the PRAD provide valuable insights for future research on PCV2 replication and antiviral strategies.


Assuntos
Circovirus , Suínos , Animais , Circovirus/genética , Adenosina Trifosfatases/genética , Cristalografia por Raios X , DNA Helicases/genética , Replicação do DNA
7.
Urolithiasis ; 52(1): 50, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554174

RESUMO

The purpose of this study was to evaluate the efficacy and safety of flexible ureteroscopy with holmium laser lithotripsy in the management of calyceal diverticular calculi. In this study, we retrospectively analyzed the clinical data of 27 patients with calyceal diverticular calculi admitted to the Department of Urology of the Zigong First People's Hospital from May 2018 to May 2021. Intraoperatively, the diverticular neck was found in all 27 patients, but flexible ureterorenoscopy lithotripsy was not performed in 2 cases because of the slender diverticular neck, and the success rate of the operation was 92.6%. Of the 25 patients with successful lithotripsy, the mean operative time was 76.9 ± 35.5 (43-200) min. There were no serious intraoperative complications such as ureteral perforation, mucosal avulsion, or hemorrhage. Postoperative minor complications (Clavien classification I-II) occurred in 4 (16%) patients. The mean hospital stay was 4.4 ± 1.7 (3-12) days. The stone-free rate was 80% at the 1-month postoperative follow-up. After the second-stage treatment, the stone-free rate was 88%. In 22 cases with complete stone clearance, no stone recurrence was observed at 5.3 ± 2.6 (3-12) months follow-up. This retrospective study demonstrated that flexible ureterorenoscopy with holmium laser is a safe and effective choice for the treatment of calyceal diverticular calculi, because it utilizes the natural lumen of the human body and has the advantages of less trauma, fewer complications, and a higher stone-free rate.


Assuntos
Divertículo , Cálculos Renais , Lasers de Estado Sólido , Litotripsia a Laser , Cálculos Ureterais , Humanos , Ureteroscopia/efeitos adversos , Estudos Retrospectivos , Lasers de Estado Sólido/efeitos adversos , Cálculos Renais/terapia , Ureteroscópios , Litotripsia a Laser/efeitos adversos , Divertículo/cirurgia , Divertículo/complicações , Complicações Pós-Operatórias , Cálculos Ureterais/complicações , Resultado do Tratamento
8.
Respir Med ; 226: 107613, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548141

RESUMO

BACKGROUND: Patients with microscopic polyangiitis (MPA) and positive myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) may present with various abnormalities in chest computed tomography (CT). This study aimed to identify subphenotypes using latent class analysis (LCA) and to explore the relationship between the subphenotypes and clinical patterns, as well as compare the clinical characteristics of these subphenotypes in patients with MPO-ANCA-positive MPA (MPO-MPA). METHODS: The study identified subphenotypes using LCA based on chest CT findings in 178 patients with MPO-MPA and pulmonary involvement from June 2014 to August 2022. RESULTS: LCA identified 27 participants (15.2%) in class 1, 43 (24.1%) in class 2, 35 (19.7%) in class 3, and 73 (41.0%) in class 4. Class 1 was characterized by prominent inflammatory exudation, class 2 by fibrosis and architectural distortion, class 3 by predominantly bronchiectasis, and class 4 by lesions mixed with inflammation and fibrosis. Class 1 had the highest level of extrapulmonary disease activity, with 77.8% of patients experiencing diffuse alveolar hemorrhage. Class 2 had the lowest level of extrapulmonary disease activity, with 41.9% of patients showing usual interstitial pneumonia. Class 3 patients were more likely to have complications involving the ear, nose, and throat, as well as pulmonary infections before treatment, and they exhibited the best outcomes. The characteristics and outcomes of class 4 were intermediate among the four classes. CONCLUSIONS: These findings suggest that bronchiectasis may represent a unique pattern of pulmonary involvement in MPO-MPA, highlighting the importance of screening for bronchiectasis in MPO-MPA and identifying optimal management strategies.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos , Análise de Classes Latentes , Poliangiite Microscópica , Peroxidase , Fenótipo , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Anticitoplasma de Neutrófilos/sangue , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Bronquiectasia/diagnóstico por imagem , Bronquiectasia/imunologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Poliangiite Microscópica/diagnóstico por imagem , Poliangiite Microscópica/imunologia , Poliangiite Microscópica/classificação , Poliangiite Microscópica/complicações , Peroxidase/imunologia , Tomografia Computadorizada por Raios X/métodos
9.
Zhongguo Zhong Yao Za Zhi ; 49(2): 370-378, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403313

RESUMO

Digitoxin, an important secondary metabolite of Digitalis purpurea, is a commonly used cardiotonic in clinical practice. 3ß-Hydroxysteroid dehydrogenase(3ßHSD) is a key enzyme involved in the biosynthesis of digitoxin. It belongs to the short-chain dehydrogenase/reductase(SDR) family, playing a role in the biosynthesis of cardiac glycosides by oxidizing and isomerizing the precursor sterol. In this study, two 3ßHSD genes were cloned from D. purpurea. The results showed that the open reading frame(ORF) of Dp3ßHSD1 was 780 bp, encoding 259 amino acid residues. The ORF of Dp3ßHSD2 was 774 bp and encoded 257 residues. Dp3ßHSD1/2 had the cofactor binding site TGxxxA/GxG and the catalytic site YxxxK. In vitro experiments confirmed that Dp3ßHSD1/2 catalyzed the generation of progesterone from pregnenolone, and Dp3ßHSD1 had stronger catalytic capacity than Dp3ßHSD2. The expression level of Dp3ßHSD1 was much higher than that of Dp3ßHSD2 in leaves, and digitoxin was only accumulated in leaves. The results implied that Dp3ßHSD1 played a role in the dehydrogenation of pregnenolone to produce progesterone in the biosynthesis of digitoxin. This study provides a reference for further exploring the biosynthetic pathway of cardiac glycosides in D. purpurea.


Assuntos
Digitoxina , Progesterona , Clonagem Molecular , Pregnenolona/metabolismo , Hidroxiesteroide Desidrogenases
10.
Photobiomodul Photomed Laser Surg ; 42(3): 238-245, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416636

RESUMO

Background: Alveolar osteitis (AO) or "dry socket" affects the quality of life of patients, and there is a high clinical demand for its effective treatment. Objective: To evaluate the effect of Er:YAG laser therapy (ErLT) on AO after mandibular third molar surgery. Methods: Eighty-three patients were randomly divided into Er (n = 43) and control groups (n = 40). In the Er group, the Er:YAG laser (2940 nm; AT Fidelis Fotona, Ljubljana, Slovenia) was used to irradiate the AO site directly in micro short-pulsed mode (pulse duration 0.1 ms, pulse energy 100 mJ, frequency 40 Hz, water 4, and air 2) until all debris and necrotic material had been removed, exposing fresh bone and soft tissue surfaces with blood exudation. The control group received mechanical therapy until the treated lesions resembled those in the Er group. Pain assessment was performed at baseline and on days 1-7 post-intervention using the visual analog scale (VAS). Wound healing was assessed using the wound healing index (WHI). The operating times of the two therapies were also recorded. Results: Group Er had lower VAS scores than the control group on days 1-3 (p = 0.00). There was no significant difference between the two groups on days 4-7 (p = 0.15). The WHI scores were better in the Er group than those in the control group (t = 2.65, p = 0.01), especially in terms of redness (t = 2.70, p = 0.01). There was no significant difference in the operating time between the two groups (t = 0.76, p = 0.45). Conclusions: Compared with mechanical therapy, ErLT for AO provides rapid pain relief and improved wound healing.


Assuntos
Alvéolo Seco , Terapia a Laser , Lasers de Estado Sólido , Humanos , Alvéolo Seco/etiologia , Alvéolo Seco/cirurgia , Dente Serotino/cirurgia , Lasers de Estado Sólido/uso terapêutico , Qualidade de Vida
11.
Int J Dermatol ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385899

RESUMO

BACKGROUND: Acute urticaria is a prevalent inflammatory dermatosis characterized by fulminant wheals, often accompanied by severe pruritis. It may also cause nausea, vomiting, and abdominal pain. Numerous studies have substantiated the pivotal involvement of double-stranded DNA (dsDNA) in autoimmunity. However, the role of dsDNA in the pathogenesis of acute urticaria is unclear. METHODS: We measured serum dsDNA levels in patients and controls. The relationship between dsDNA levels and environmental exposures (temperature, ultraviolet [UV] index, and season) was investigated by correlating disease onset dates with archived meteorological data. Finally, we used quantitative PCR to determine the expressions of genes encoding dsDNA receptors, single-stranded RNA (ssRNA) receptors, exosome formation, and type I interferon in the peripheral blood of patients and controls. RESULTS: Serum dsDNA levels were significantly higher in patients with acute urticaria compared with controls (mean values 1.38 and 0.94 ng/ml, respectively, P < 0.001). dsDNA levels were higher in patients exposed to higher environmental temperatures and UV indices and were higher during the summer months. We also found that the expressions of genes encoding dsDNA receptors, ssRNA receptors, absent in melanoma factor 2 (AIM2)-related inflammatory factors, and interferon alpha were up-regulated in patients. CONCLUSIONS: We demonstrated that serum dsDNA levels are elevated in acute urticaria and are influenced by climatic factors such as temperature, ultraviolet index, and season. We also found that elevated dsDNA promotes the expression of AIM2-related factors and type I interferons. This study generates new hypotheses regarding the pathogenesis of acute urticaria and suggests novel therapeutic targets.

12.
Cell Chem Biol ; 31(3): 487-501.e7, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38232732

RESUMO

Structural dynamics of human immunodeficiency virus 1 (HIV-1) envelope (Env) glycoprotein mediate cell entry and facilitate immune evasion. Single-molecule FRET using peptides for Env labeling revealed structural dynamics of Env, but peptide use risks potential effects on structural integrity/dynamics. While incorporating noncanonical amino acids (ncAAs) into Env by amber stop-codon suppression, followed by click chemistry, offers a minimally invasive approach, this has proved to be technically challenging for HIV-1. Here, we develope an intact amber-free HIV-1 system that overcomes hurdles of preexisting viral amber codons. We achieved dual-ncAA incorporation into Env on amber-free virions, enabling single-molecule Förster resonance energy transfer (smFRET) studies of click-labeled Env that validated the previous peptide-based labeling approaches by confirming the intrinsic propensity of Env to dynamically sample multiple conformational states. Amber-free click-labeled Env also enabled real-time tracking of single virion internalization and trafficking in cells. Our system thus permits in-virus bioorthogonal labeling of proteins, compatible with studies of virus entry, trafficking, and egress from cells.


Assuntos
HIV-1 , Provírus , Humanos , Imagem Individual de Molécula , Proteínas/metabolismo , Peptídeos/metabolismo
13.
PeerJ ; 12: e16677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188177

RESUMO

In recent years, numerous studies have investigated the effects of caffeine on exercise, and provide convincing evidence for its ergogenic effects on exercise performance. However, the precise mechanisms underlying these ergogenic effects remain unclear. In this study, an exercise swimming model was conducted to investigate the effects of orally administered with caffeine before swimming on the alterations of proteome and energy metabolome of liver and muscle after swimming. We found proteins in liver, such as S100a8, S100a9, Gabpa, Igfbp1 and Sdc4, were significantly up-regulated, while Rbp4 and Tf decreased after swimming were further down-regulated in caffeine group. The glycolysis and pentose phosphate pathways in liver and muscle were both significantly down-regulated in caffeine group. The pyruvate carboxylase and amino acid levels in liver, including cysteine, serine and tyrosine, were markedly up-regulated in caffeine group, exhibiting a strong correlation with the increased pyruvic acid and oxaloacetate levels in muscle. Moreover, caffeine significantly decreased the lactate levels in both liver and muscle after swimming, potentially benefiting exercise performance.


Assuntos
Cafeína , Substâncias para Melhoria do Desempenho , Animais , Camundongos , Cafeína/farmacologia , Natação , Multiômica , Fígado , Músculos , Metabolismo Energético
14.
Sci Rep ; 14(1): 418, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172585

RESUMO

Boron Neutron Capture Therapy (BNCT) is a radiotherapy technique based on the enrichment of tumour cells with suitable 10-boron concentration and on subsequent neutron irradiation. Low-energy neutron irradiation produces a localized deposition of radiation dose caused by boron neutron capture reactions. Boron is vehiculated into tumour cells via proper borated formulations, able to accumulate in the malignancy more than in normal tissues. The neutron capture releases two high-LET charged particles (i.e., an alpha particle and a lithium ion), losing their energy in a distance comparable to the average dimension of one cell. Thus BNCT is selective at the cell level and characterized by high biological effectiveness. As the radiation field is due to the interaction of neutrons with the components of biological tissues and with boron, the dosimetry requires a formalism to express the absorbed dose into photon-equivalent units. This work analyzes a clinical case of an adenoid cystic carcinoma treated with carbon-ion radiotherapy (CIRT), located close to optic nerve and deep-seated as a practical example of how to apply the formalism of BNCT photon isoeffective dose and how to evaluate the BNCT dose distribution against CIRT. The example allows presenting different dosimetrical and radiobiological quantities and drawing conclusions on the potential of BNCT stemming on the clinical result of the CIRT. The patient received CIRT with a dose constraint on the optic nerve, affecting the peripheral part of the Planning Target Volume (PTV). After the treatment, the tumour recurred in this low-dose region. BNCT was simulated for the primary tumour, with the goal to calculate the dose distribution in isoeffective units and a Tumour Control Probability (TCP) to be compared with the one of the original treatment. BNCT was then evaluated for the recurrence in the underdosed region which was not optimally covered by charged particles due to the proximity of the optic nerve. Finally, a combined treatment consisting in BNCT and carbon ion therapy was considered to show the consistency and the potential of the model. For the primary tumour, the photon isoeffective dose distribution due to BNCT was evaluated and the resulted TCP was higher than that obtained for the CIRT. The formalism produced values that are consistent with those of carbon-ion. For the recurrence, BNCT dosimetry produces a similar TCP than that of primary tumour. A combined treatment was finally simulated, showing a TCP comparable to the BNCT-alone with overall dosimetric advantage in the most peripheral parts of the treatment volume. Isoeffective dose formalism is a robust tool to analyze BNCT dosimetry and to compare it with the photon-equivalent dose calculated for carbon-ion treatment. This study introduces for the first time the possibility to combine the dosimetry obtained by two different treatment modalities, showing the potential of exploiting the cellular targeting of BNCT combined with the precision of charged particles in delivering an homogeneous dose distribution in deep-seated tumours.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias de Cabeça e Pescoço , Radioterapia com Íons Pesados , Humanos , Terapia por Captura de Nêutron de Boro/métodos , Boro , Carbono , Nêutrons
15.
RSC Adv ; 14(6): 3952-3961, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38288144

RESUMO

We have devised a moderate temperature spark plasma sintering route for preparing aluminum matrix composites which possess tailored coefficients of thermal expansion (CTEs) in combination with tunable electrical and thermal conductivities. Due to its isotropic negative thermal expansion over a wide temperature range, cubic-phase ZrW2-xMoxO8 (x = 0.0, 1.0) is an ideal secondary phase for metal matrix composites with suitable CTEs. In this study, high-density ZrW2O8/Al and ZrWMoO8/Al composites containing 30-70 vol% Al were fabricated using spark plasma sintering. X-ray diffraction analysis indicated that the composites were composed of a thermally-stable cubic phase at temperatures as high as 873 K for ZrW2O8 and 773 K for ZrWMoO8, without any orthorhombic high-pressure phase derived from the large thermal mismatch between the ceramic and metal during sintering. The thermal expansion curves of the ZrW2-xMoxO8/Al composites were consistent with the predictions made using the Rule-of-Mixtures. The CTEs could be controlled from negative to positive and even close to zero by simply varying the volume fraction of aluminum. Similarly, the thermal and electrical conductivity of the ZrW2-xMoxO8/Al composites increases with increasing Al content, which is thought to be mainly related to the contribution of the free electron conduction path of Al in the composites.

16.
Explore (NY) ; 20(1): 126-129, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37286465

RESUMO

Malignant pleural mesothelioma (MPM) is a severe form of cancer that originates from mesothelium cells. Around 54-90% of mesotheliomas are associated with pleural effusions. Brucea Javanica Oil Emulsion (BJOE) is the processed oil derived from the seeds of Brucea javanica, which has shown potential as a treatment option for several types of cancer. Here, we present a case study of a MPM patient with malignant pleural effusion who received intrapleural injection of BJOE. The treatment resulted in the complete response of pleural effusion and chest tightness. While the precise mechanisms underlying the therapeutic effects of BJOE for pleural effusion are not yet fully understood, it has demonstrated a satisfactory clinical response without significant adverse effects.


Assuntos
Brucea , Mesotelioma Maligno , Mesotelioma , Derrame Pleural Maligno , Humanos , Brucea javanica , Emulsões/uso terapêutico , Mesotelioma/complicações , Mesotelioma/tratamento farmacológico , Óleos de Plantas/uso terapêutico , Derrame Pleural Maligno/tratamento farmacológico , Derrame Pleural Maligno/patologia
17.
Anal Chem ; 96(1): 301-308, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38102984

RESUMO

Developing new strategies to construct sensor arrays that can effectively distinguish multiple natural components with similar structures in mixtures is an exceptionally challenging task. Here, we propose a new multilocus distance-modulated indicator displacement assay (IDA) strategy for constructing a sensor array, incorporating machine learning optimization to identify polyphenols. An 8-element array, comprising two fluorophores and their six dynamic covalent complexes (C1-C6) formed by pairing two fluorophores with three distinct distance-regulated quenchers, has been constructed. Polyphenols with diverse spatial arrangements and combinatorial forms compete with the fluorophores by forming pseudocycles with quenchers within the complexes, leading to varying degrees of fluorescence recovery. The array accurately and effectively distinguished four tea polyphenols and 16 tea varieties, thereby demonstrating the broad applicability of the multilocus distance-modulated IDA array in detecting polyhydroxy foods and natural medicines.


Assuntos
Polifenóis , Chá , Espectrometria de Fluorescência , Aprendizado de Máquina
18.
Phys Med Biol ; 69(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38048635

RESUMO

Objective. Boron neutron capture therapy (BNCT) and carbon ion radiotherapy (CIRT) are emerging treatment modalities for glioblastoma. In this study, we investigated the methodology and feasibility to combine BNCT and CIRT treatments. The combined treatment plan illustrated how the synergistic utilization of BNCT's biological targeting and CIRT's intensity modulation capabilities could lead to optimized treatment outcomes.Approach. The Monte Carlo toolkit, TOPAS, was employed to calculate the dose distribution for BNCT, while matRad was utilized for the optimization of CIRT. The biological effect-based approach, instead of the dose-based approach, was adopted to develop the combined BNCT-CIRT treatment plans for six patients diagnosed with glioblastoma, considering the different radiosensitivity and fraction. Five optional combined treatment plans with specific BNCT effect proportions for each patient were evaluated to identify the optimal treatment that minimizes damage on normal tissue.Main results. Individual BNCT exhibits a significant effect gradient along with the beam direction in the large tumor, while combined BNCT-CIRT treatments can achieve uniform effect delivery within the clinical target volume (CTV) through the effect filling with reversed gradient by the CIRT part. In addition, the increasing BNCT effect proportion in combined treatments can reduce damage in the normal brain tissue near the CTV. Besides, the combined treatments effectively minimize damage to the skin compared to individual BNCT treatments.Significance. The initial endeavor to combine BNCT and CIRT treatment plans is achieved by the effect-based optimization. The observed advantages of the combined treatment suggest its potential applicability for tumors characterized by pleomorphic, infiltrative, radioresistant and voluminous features.


Assuntos
Terapia por Captura de Nêutron de Boro , Glioblastoma , Radioterapia com Íons Pesados , Humanos , Glioblastoma/radioterapia , Terapia por Captura de Nêutron de Boro/métodos , Encéfalo , Dosagem Radioterapêutica
19.
Front Neurol ; 14: 1273822, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941571

RESUMO

Background: Cerebral extracranial-intracranial (EC-IC) revascularization technique (superficial temporal artery-middle cerebral artery (STA-MCA) bypass grafting) has become the preferred surgical method for the treatment of Moyamoya disease (MMD). We attempted to completely free the two branches of the superficial temporal artery without disconnection. Extracranial and intracranial blood flow reconstruction were then modified by selectively performing a direct bypass technique on one branch and a patch fusion technique on the other of the STA based on the blood flow and the vascular diameter of the intracranial surface blood vessels. Methods: A series of modified STA-MCA bypass surgeries performed consecutively between March 2022 and March 2023 were reviewed and compared to conventional combined bypass surgeries performed during the same period. The following information was collected from all enrolled patients: demographic characteristics, clinical symptoms, and preoperative and postoperative imaging, including Suzuki stage and Matsushima grade. The modified Rankin scale (mRS) was used to assess the changes in neurological status before and after surgery. Results: A total of 41 patients with Moyamoya disease (MMD) who underwent cerebral revascularization were included in this study, of which 30 were conventional revascularization and 11 were modified revascularization. The mean age was 49.91 years, and 18 (43.9%) of the patients were women. The modified group had a lower incidence of cerebral hyperperfusion syndrome (18.2%) than the conventional group (23.3%). After at least 3 months of follow-up, the bypass patency rate remained 100% in the modified group and 93.3% in the conventional group. All patients in the modified group achieved a better Matsushima grade (A + B), with six (54.5%) having an A and five (45.5%) having a B. In contrast, four patients (13.3%) in the conventional group had a Matsushima grade of C. In all, 72.8% of the modified group had postoperative mRS scores of 0 and 1, which was higher than that of the traditional group (63.3%). Conclusion: The improved STA-MCA bypass could provide blood flow to multiple cerebral ischemic areas, reduce excessive blood perfusion, and ensure blood supply to the scalp, with lower complications and better clinical benefits than the traditional combined bypass.

20.
Angew Chem Int Ed Engl ; 62(52): e202314832, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37946607

RESUMO

The Stille cross-coupling reaction is one of the most common strategies for the construction of C-C bonds. Despite notable strides in the advancement of the Stille reaction, persistent challenges persist in hindering its greener evolution. These challenges encompass multiple facets, such as the high cost of precious metals and ligands, the demand for various additives, and the slow reaction rate. In comparison to the dominant palladium-catalysed Stille reactions, cost-effective nickel-catalysed systems lag behind, and enantioconvergent Stille reactions of racemic stannanes remain undeveloped. Herein, we present a pioneering instance of nickel-catalysed enantioconvergent Stille cross-coupling reactions of racemic stannane reagents, resulting in the formation of C-C bonds in good to high yields with excellent stereoselectivity. This strategy provides a practical, scalable, and operationally straightforward method for the synthesis of C(sp3 )-C(sp3 ), C(sp3 )-C(sp2 ), and C(sp3 )-C(sp) bonds under exceptionally mild conditions (without additives and bases, ambient temperature). The innovative use of synergistic photoredox/nickel catalysis enables a novel single-electron transmetalation process of stannane reagents, providing a new research paradigm of Stille reactions.

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