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1.
Anal Chem ; 96(4): 1795-1802, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38241199

RESUMO

Cytokines are essential components of the immune system and are recognized as significant biomarkers. However, detection of a single cytokine is not precise and reliable enough to satisfy the requirements for diagnosis. Herein, we developed a pattern recognition-based method for the multiplexed sensing of cytokines, which involves three-color-emitting boronic acid-decorated carbon dots (BCDs) and arginine-modified titanium carbide (Ti3C2 MXenes) as the sensor array. Initially, the fluorescence signals of the three BCDs were quenched by Ti3C2 MXenes. In the presence of cytokines, the fluorescence intensity of the BCDs was restored or further quenched by different cytokines. The fluorescence response occurs in two steps: first, boronic acid interacts with cis-diol functional groups of cytokines, and second, arginine headgroup selectively interacts with glycans. By exploiting the different competing binding of the BCDs and the cytokines toward Ti3C2 MXenes, seven cytokines and their mixtures can be effectively discriminated at a concentration of 20 ng mL-1. Furthermore, our sensor array demonstrated an excellent performance in classifying human oral cancer saliva samples from healthy individuals with clinically relevant specificity. The noninvasive method offers a rapid approach to cytokine analysis, benefiting early and timely clinical diagnosis and treatment.


Assuntos
Citocinas , Neoplasias Bucais , Humanos , Carbono , Ácidos Borônicos , Neoplasias Bucais/diagnóstico , Arginina
2.
Anal Chem ; 96(8): 3436-3444, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38372258

RESUMO

Cerebral ischemia-reperfusion injury (CIRI), a cause of cerebral dysfunction during cerebral infarction treatment, is closely associated with mitochondrial viscosity and hydrogen peroxide (H2O2). However, the accurate measurement of mitochondrial viscosity and H2O2 levels in CIRI is challenging because of the lack of sufficient selectivity and blood-brain barrier (BBB) penetration of existing monitoring tools related to CIRI, hampering the exploration of the role of mitochondrial viscosity and H2O2 in CIRI. To address this issue, we designed an activatable fluorescent probe, mitochondria-targeting styryl-quinolin-ium (Mito-IQS), with excellent properties including high selectivity, mitochondrial targeting, and BBB penetration, for the visualization of mitochondrial viscosity and H2O2 in the brain. Based on the real-time monitoring capabilities of the probe, bursts of mitochondrial viscosity and H2O2 levels were visualized during CIRI. This probe can be used to monitor the therapeutic effects of butylphthalein treatment. More importantly, in vivo experiments further confirmed that CIRI was closely associated with the mitochondrial viscosity and H2O2 levels. This discovery provides new insights and tools for the study of CIRI and is expected to accelerate the process of CIRI diagnosis, treatment, and drug design.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Humanos , Peróxido de Hidrogênio , Corantes Fluorescentes , Viscosidade , Mitocôndrias
3.
HIV Med ; 25(1): 60-71, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37574804

RESUMO

OBJECTIVES: Despite the improved survival of patients with AIDS and Kaposi's sarcoma (KS), competing events are a non-negligible issue affecting the survival of such patients. In this study, we explored the prognostic factors of KS-specific and non-KS-specific mortality in patients with AIDS-related KS (AIDS-KS), accounting for competing risk. METHODS: We identified 17 103 patients with AIDS-KS aged 18-65 years between 1980 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) 18 registry database. Prognostic factors for KS-specific and non-KS-specific mortality were determined by the Fine and Grey proportional subdistribution hazard model. We built competing risk nomograms and assessed their predictive performance based on the identified prognostic factors. RESULTS: In total, 12 943 (75.68%) patients died, 1965 (15.50%) of whom died from competing events. The KS-specific mortality rate was 14 835 per 100 000 person-years, and the non-KS specific mortality rate was 2719 per 100 000 person-years. Specifically, age >44 years was associated with an 11% decrease in the subdistribution hazard of KS-specific mortality compared with age <43 years but a 50% increase in the subdistribution hazard of non-KS-specific mortality. Being male was associated with a 26% increase in the subdistribution hazard of KS-specific mortality compared with being female but a 32% decrease in the subdistribution hazard of non-KS-specific mortality. Notably, being in the antiretroviral therapy (ART) era consistently showed a decrease in the subdistribution hazard of both KS-specific and non-KS-specific mortality than being in the pre-ART era. CONCLUSIONS: Competing events commonly occurred among patients with AIDS-KS, which deserves further attention to improve the prognosis of these patients.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Sarcoma de Kaposi , Humanos , Masculino , Feminino , Sarcoma de Kaposi/epidemiologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Infecções por HIV/complicações , Prognóstico
4.
Artigo em Inglês | MEDLINE | ID: mdl-39325156

RESUMO

PURPOSE: The image-derived input function (IDIF) from the descending aorta has demonstrated performance comparable to arterial blood sampling while avoiding its invasive nature in parametric imaging. However, in conventional PET, large vessels may not always be within the imaging field of view (FOV). This study aims to evaluate the efficacy of dynamic parametric Ki imaging using image-derived input functions (IDIFs) extracted from various arteries, facilitated by total-body PET/CT. METHOD: Twenty-three participants underwent a 60-minute total-body [18F]FDG PET scan. Data from each subject were used to reconstruct both total-body PET images and short-axis field-of-view PET images at different bed positions, each with a 25 cm axial field-of-view (AFOV). Partial volume correction (PVC) was performed using the blurred Van Cittert iterative deconvolution. IDIFs extracted from the descending aorta, carotid artery, abdominal aorta, and iliac artery were employed for Patlak analysis. The resulting Ki images were compared using quantification indicators and subjective assessment. Linear regression analysis was conducted to examine the correlation of Ki values among IDIFs in normal organ and lesion regions of interest (ROIs). RESULT: High similarities were observed in Ki images derived from the IDIFs from the descending aorta and other arteries, with a median structural similarity index measure (SSIM) above 0.98 and a median peak signal-to-noise ratio (PSNR) above 37dB. Linear regression analysis revealed strong correlations in Ki values (r² > 0.88) between the descending aorta and the three alternative vessels, with slopes of the linear fits close to 1. No significant difference in lesion detectability among IDIFs was found, as assessed visually and using metrics such as tumor-to-background ratio (TBR) and contrast-to-noise ratio (CNR) (P < 0.05). CONCLUSION: IDIFs from smaller vessels can reliably reconstruct parametric Ki images without compromising lesion detectability, providing clinically relevant information.

5.
Eur J Nucl Med Mol Imaging ; 51(9): 2744-2757, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38587644

RESUMO

PURPOSE: Radiopharmaceutical therapies targeting fibroblast activation protein (FAP) have shown promising efficacy against many tumor types. But radiopharmaceuticals alone in most cases are insufficient to completely eradicate tumor cells, which can partially be attributed to the protective interplay between tumor cells and cancer-associated fibroblasts (CAFs). The C-X-C chemokine receptor type 4/C-X-C motif chemokine 12 (CXCR4/CXCL12) interaction plays an important role in orchestrating tumor cells and CAFs. We hereby investigated the feasibility and efficacy of [177Lu]Lu-DOTAGA.(SA.FAPi)2, a FAP-targeting radiopharmaceutical, in combination with AMD3100, a CXCR4 antagonist, in a preclinical murine model of triple-negative breast cancer (TNBC). METHODS: Public database was first interrogated to reveal the correlation between CAFs' scores and the prognosis of TNBC patients, as well as the expression levels of FAP and CXCR4 in normal tissues and tumors. In vitro therapeutic efficacy regarding cell proliferation, migration, and colony formation was assessed in BALB/3T3 fibroblasts and 4T1 murine breast cancer cells. In vivo therapeutic efficacy was longitudinally monitored using serial 18F-FDG, [18F]AlF-NOTA-FAPI-04, and [68Ga]Ga-DOTA-Pentixafor PET/CT scans and validated using tumor sections through immunohistochemical staining of Ki-67, α-SMA, CXCR4, and CXCL12. Intratumoral abundance of myeloid-derived suppressive cells (MDSCs) was analyzed using flow cytometry in accordance with the PET/CT schedules. Treatment toxicity was evaluated by examining major organs including heart, lung, liver, kidney, and spleen. RESULTS: CAFs' scores negatively correlated with the survival of TNBC patients (p < 0.05). The expression of CXCR4 and FAP was both significantly higher in tumors than in normal tissues. The combination of [177Lu]Lu-DOTAGA.(SA.FAPi)2 and AMD3100 significantly suppressed cell proliferation, migration, and colony formation in cell culture, and exhibited synergistic effects in 4T1 tumor models along with a decreased number of MDSCs. PET/CT imaging revealed lowest tumor accumulation of 18F-FDG and [18F]AlF-NOTA-FAPI-04 on day 13 and day 14 after treatment started, both of which gradually increased at later time points. A similar trend was observed in the IHC staining of Ki-67, α-SMA, and CXCL12. CONCLUSION: The combination of [177Lu]Lu-DOTAGA.(SA.FAPi)2 and AMD3100 is a feasible treatment against TNBC with minimal toxicity in main organs.


Assuntos
Quimiocina CXCL12 , Receptores CXCR4 , Neoplasias de Mama Triplo Negativas , Receptores CXCR4/metabolismo , Receptores CXCR4/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/radioterapia , Animais , Camundongos , Quimiocina CXCL12/metabolismo , Humanos , Linhagem Celular Tumoral , Feminino , Ciclamos/farmacologia , Ciclamos/uso terapêutico , Lutécio , Benzilaminas/farmacologia , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/química , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/farmacologia , Endopeptidases , Proliferação de Células/efeitos dos fármacos , Gelatinases/metabolismo , Proteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo
6.
Mol Pharm ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39186477

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a fatal disease characterized by unpredictable progression and limited therapeutic options. Current diagnosis relies on high resolution computed tomography (HRCT), which may not adequately capture early signs of deterioration. The enzyme autotaxin (ATX) emerges as a prominently expressed extracellular secretory enzyme in the lungs of IPF patients. The objective of this study was to evaluate the effectiveness of 18F-labeled ATX-targeted tracer [18F]ATX-1905, in comparison with [18F]FDG, for early fibrosis diagnosis, disease evolution monitoring, and treatment efficacy assessment in bleomycin-induced pulmonary fibrosis (BPF) models. To assess treatment efficacy, mice were treated with two commonly used drugs for IPF, pirfenidone or nintedanib, from Day 9 to Day 23 postbleomycin administration. Lung tissue assessments encompassed inflammation severity via H&E staining, and Ashcroft scoring via Masson staining, alongside quantification of ATX expression through ELISA. Positron emission tomography (PET) imaging employing [18F]FDG and [18F]ATX-1905 tracked disease progression pre- and post-treatment. The extent of pulmonary fibrosis corresponded to changes in ATX expression levels in the BPF mouse model. Notably, [18F]ATX-1905 exhibited elevated uptake in BPF lungs during the progression of the disease, particularly evident at the early stage (Day 9). This uptake was inhibited by an ATX inhibitor, PF-8380, underscoring the specificity of the radiotracer. Conversely, [18F]FDG uptake, peaking at Day 15, decreased subsequently, likely reflective of diminished inflammation. A 2-week treatment regimen using either pirfenidone or nintedanib resulted in notable reductions of ATX expression levels and fibrosis degrees within lung tissues, based on ELISA and Masson staining, as evidenced by PET imaging with [18F]ATX-1905. [18F]FDG uptake also decreased following the treatment period. Additionally, PET/CT imaging extended to a nonhuman primate (NHP) BPF model. The uptake of [18F]ATX-1905 (SUVmax = 2.2) was significantly higher than that of [18F]FDG (SUVmax = 0.7) in fibrotic lung tissue. Using our novel ATX-specific radiotracer [18F]ATX-1905 and PET/CT imaging, we demonstrated excellent ability in early fibrosis detection, disease monitoring, and treatment assessment within lungs of the BPF mouse models. [18F]ATX-1905 displayed remarkable specificity for ATX expression and high sensitivity for ATX alterations, suggesting its potential for monitoring varying ATX expression in lungs of IPF patients.

7.
Langmuir ; 40(20): 10449-10459, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717310

RESUMO

It is widely acknowledged that doping silicon can significantly enhance the friction performance of diamond-like carbon (DLC) films in a water environment. However, the mechanism of low friction caused by doped silicon is still highly controversial. Therefore, this article compares the interface interaction between DLC and Si-DLC films in a water environment through first-principles calculations of physisorption and chemisorption effects. The results indicate that water molecules are predominantly chemically adsorbed rather than physically adsorbed on the Si-DLC surface. Further study reveals that when OH-termination is formed on the Si-DLC surface, water molecules are predominantly physically adsorbed rather than chemically adsorbed on the Si-DLC hydroxylation surface. Consequently, a more stable hydration layer is formed on the surface through the hydrogen bond network formed by Si-OH groups, ultimately leading to lower friction. Moreover, molecular dynamics simulations further suggest that the lower friction coefficient of Si-DLC films in a water environment may be due to more water molecules at the friction interface and fewer interface covalent bonds. In short, the low-friction coefficient of the Si-DLC film in a water environment may be caused not only by the chemisorption of water molecules on its surface but also by the physisorption of water molecules on the Si-DLC film after surface hydroxylation.

8.
Langmuir ; 40(4): 2369-2376, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38230676

RESUMO

Urinary tract infections (UTIs) have greatly affected human health in recent years. Accurate and rapid diagnosis of UTIs can enable a more effective treatment. Herein, we developed a multichannel sensor array for efficient identification of bacteria based on three antimicrobial agents (vancomycin, lysozyme, and bacitracin) functional gold nanoclusters (AuNCs). In this sensor, the fluorescence intensity of the three AuNCs was quenched to varying degrees by the bacterial species, providing a unique fingerprint for different bacteria. With this sensing platform, seven pathogenic bacteria, different concentrations of the same bacteria, and even bacterial mixtures were successfully differentiated. Furthermore, UTIs can be accurately identified with our sensors in ∼30 min with 100% classification accuracy. The proposed sensing systems offer a rapid, high-throughput, and reliable sensing platform for the diagnosis of UTIs.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Humanos , Ouro , Vancomicina , Bactérias , Espectrometria de Fluorescência
9.
J Pediatr Hematol Oncol ; 46(7): 356-363, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39196630

RESUMO

X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV) infection, and neoplasia (XMEN) is an extremely rare inborn error of immunity (IEI) caused by X-linked recessive inheritance and loss-of-function mutations in the MAGT1 gene, resulting in magnesium ion channel defects. This article reports 2 cases of systemic EBV-positive T-cell Lymphoma of childhood (SETLC) associated with XMEN, which have not been reported before. Whole exome sequencing (WES) in their family revealed previously unreported MAGT1 gene mutations (c.77T>C, p.I26T; c.956-957del: p.Ser319Tyrfs) inherited from their mothers. These mutations expand the spectrum of gene mutations in XMEN disease. The importance of genetic testing for MAGT1 mutations in the initial diagnosis of SETLC was emphasized. We also review the literature on this uncommon IEI.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma de Células T , Humanos , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Masculino , Linfoma de Células T/genética , Linfoma de Células T/patologia , Linfoma de Células T/virologia , Linfoma de Células T/complicações , Proteínas de Transporte de Cátions/genética , Mutação , Feminino , Criança , Herpesvirus Humano 4/isolamento & purificação , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/complicações , Pré-Escolar , Sequenciamento do Exoma
10.
BMC Public Health ; 24(1): 1120, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654229

RESUMO

BACKGROUND: Dietary rationality and health concept have certain influence on individual health level. This study aims to explore the characteristics and existing problems of Chinese residents' health behaviors from both macro and micro perspectives, and explore the feasibility and realization path of Healthy China strategy. METHODS: We utilized regression models to evaluate the correlation between diet and the risk of disease causes of death. By use of the linear regression analysis model, we distinguished the impact of each dimension on health literacy index at the individual level. Then, we explored the influential factors of the diet health index using the binary logit regression model. RESULTS: Increased consumption of animal-derived foods in China has contributed to the burden of non-communicable diseases. The individuals' health awareness is still weak, and the health literacy index is greatly affected by the diet, while the individual gender and age are positively correlated with the diet health index, and the individual body mass index (BMI) level is negatively correlated with the diet health index. CONCLUSIONS: This study provided a comprehensive understanding of existing problems of Chinese residents' health behaviors. We have proposed a path model for the implementation of the Healthy China strategy from the perspectives of "diet health, physical health, conceptual health and environmental health," which is also a great contribution to the world.


Assuntos
Comportamentos Relacionados com a Saúde , Humanos , China , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Dieta , Letramento em Saúde , Idoso , Dieta Saudável , Adulto Jovem
11.
Anal Chem ; 95(14): 5911-5919, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36975193

RESUMO

The composition and activity of the gut microbiota are crucial for health management and disease treatment. Herein, we develop a rapid and robust multichannel sensor array via a recognition engineering strategy using antimicrobial agent (vancomycin, bacitracin, and lysozyme) functional gold nanoclusters and gluconamide-modified Ti3C2 MXenes, which provide superior fingerprint patterns to distinguish gut-derived bacteria. The discrimination ability of the sensor array was highly improved via the synergistic recognition between the bacteria and the various antimicrobial agents. Five gut-derived bacteria, including probiotics, neutral, and pathogenic bacteria were clearly differentiated and discriminated from the bacteria mixtures. Furthermore, the sensing system was successfully applied for the accurate classification of human colorectal cancer samples from healthy individuals rapidly (30 min) with clinically relevant specificity. The rapidity, simplicity, and economic cost of this strategy offers a robust platform for gut microbiota analysis.


Assuntos
Microbioma Gastrointestinal , Humanos , Vancomicina
12.
Hum Brain Mapp ; 44(2): 472-483, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069128

RESUMO

The aim of this study was to explore the influences of age-matched control and/or age-specific template on voxel-wise analysis of brain 18 F-fluorodeoxyglucose positron emission tomography (18 F-FDG PET) data in pediatric epilepsy patients. We, retrospectively, included 538 pediatric (196 females; age range of 12 months to 18 years) and 35 adult subjects (18 females; age range of 20-50 years) without any cerebral pathology as pediatric and adult control group, respectively, as well as 109 pediatric patients with drug-resistant epilepsy (38 females; age range of 13 months to 18 years) as epilepsy group. Statistical parametric mapping (SPM) analysis for 18 F-FDG PET data of each epilepsy patients was performed in four types of procedures, by using age-matched controls with age-specific template, age-matched controls with adult template, adult controls with age-specific template or adult controls with adult template. The numbers of brain regions affected by artifacts among these four types of SPM analysis procedures were further compared. Any template being adopted, the artifacts were significantly less in SPM analysis procedures using age-matched controls than those using adult controls in each age range (p < .001 in each comparison), except in the age range of 15-18 (p > .05 in each comparison). No significant difference was found in artifacts, when compared procedures using the identical control group with different templates (p = 1.000 in each comparison). In conclusion, the age stratification for age-matched control should be divided as many layers as possible for the SPM analysis of brain 18 F-FDG PET images, especially in pediatric patients ≤14-year-old, while age-specific template is not mandatory.


Assuntos
Epilepsia , Fluordesoxiglucose F18 , Adulto , Feminino , Humanos , Criança , Lactente , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Fluordesoxiglucose F18/metabolismo , Estudos Retrospectivos , Epilepsia/diagnóstico por imagem , Epilepsia/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Mapeamento Encefálico , Fatores Etários , Compostos Radiofarmacêuticos
13.
Mol Pharm ; 20(5): 2443-2451, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37067162

RESUMO

Fibroblast activation protein (FAP) is highly expressed in many tumor types and constitutes a promising target for tumor-specific delivery of therapeutic radionuclides. [177Lu]Lu-DOTAGA.(SA.FAPi)2 is a novel radiopharmaceutical based on a novel bidentate inhibitor of FAP that is excreted more slowly than its monomeric counterparts. Still, the efficacy of radiotherapy is mitigated by cascades of DNA damage repair signaling in tumor cells including those via Poly(ADP-ribose) polymerase (PARP). We hereby aimed to evaluate the efficacy of [177Lu]Lu-DOTAGA.(SA.FAPi)2 in combination with a PARP inhibitor, Olaparib, in the 4T1 murine triple negative breast cancer (TNBC) model. The therapeutic efficacy was visualized using 18F-FDG and [68Ga]Ga-FAPI-04 positron emission imaging/computer tomography (PET/CT). Our results demonstrated that Olaparib suppressed BALB/3T3 fibroblasts in vitro and sensitized the efficacy of [177Lu]Lu-DOTAGA.(SA.FAPi)2 in mice bearing 4T1 tumors via enhancement of DNA damage. Treatment-associated toxicity was tolerable with only mild leukopenia. Therefore, the combination of [177Lu]Lu-DOTAGA.(SA.FAPi)2 and Olaparib is a feasible treatment against TNBC.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Camundongos , Animais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/genética , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Radioisótopos de Gálio/uso terapêutico
14.
Langmuir ; 39(37): 13386-13398, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37688790

RESUMO

Cuttings particles of different sizes in the drilling fluid are the leading cause of wear at the casing and drill pipe joints, and diamond-like carbon (DLC) films have excellent research potential in reducing tool wear due to their ultra-low friction coefficient and high wear resistance. In this paper, a corresponding molecular dynamics model was developed using LAMMPS to investigate the effect of silica particles of different particle sizes on the friction and wear mechanisms of Fe/DLC friction pairs at the microscale. The results show that small cuttings particles in a dry environment are more likely to cause interface wear between the casing and drill pipe joint, while in a water environment, the opposite is true. The main reason is that small particles in a dry environment have smaller contact areas and greater indentation depth, leading to greater wear at the friction interface. The movement of water molecules in the water environment will promote the composite movement of large particles, thereby exacerbating the wear of the interface. Moreover, the relevant research results at the micro-scale indicate that DLC films can effectively reduce wear, which provides theoretical support for its application in drill pipe joints.

15.
Langmuir ; 39(14): 5145-5155, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37010490

RESUMO

In this paper, the frictional behaviors of Fe-Cr alloys in the lubricating effect of oil-based lubricant are investigated through reactive molecular dynamics. It is shown that the oil-based lubricant achieves ultralow friction through hydrodynamic lubrication by linear alpha olefin (C8H16) and passivation of the friction pairs by hydrogen gas (H2) and free H atoms generated by the friction chemistry. Moreover, there is a critical value for the transition of the crystal structure of Fe-Cr alloy from body-centered cubic (Bcc) to amorphous structure (Other), leading to a dramatic change in friction. Meanwhile, a sliding interface consisting of a large number of amorphous structures is formed near the rigid layer, which keeps the friction force stable.

16.
Langmuir ; 39(5): 1905-1913, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36700881

RESUMO

Whether a graphitization mechanism can control the low-friction behavior of DLC films is still controversial. In this paper, we establish the molecular dynamics model of the DLC film with graphene (DLC-GR-DLC) by LAMMPS and study the influence of the graphitization mechanism on the friction and wear behavior of the DLC film. The friction force of the DLC-GR-DLC model in the running-in stage is significantly smaller than that of the DLC film and then gradually increases to the same size as that of the DLC film. Further analysis indicates that the graphitization mechanism could indeed reduce the shear stress of the friction interface when graphene remains intact. However, the curling and breaking of the graphene structure will lead to an increase in shear force at the friction interface.

17.
Neuroendocrinology ; 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37088082

RESUMO

INTRODUCTION: The ability of PET/CT imaging to delineate neuroendocrine neoplasms (NENs) and predict prognosis in affected patients is often compromised by substantial uptake heterogeneity. We hereby proposed a hybrid standardized uptake value (SUV) thresholding algorithm to extract volumetric parameters from somatostatin receptor (SSTR) PET/CT imaging, and investigate their prognostic performance in patients with 68Ga-DOTATATE-avid stage IV NENs. METHODS: For 38 retrospectively enrolled patients, we used either fixed SUV thresholding of normal liver parenchyma (method A), 41% of the SUVmax for each lesion (method B), or a hybrid method (method A for liver metastases; fixed SUV threshold of normal bone for bone metastases; method B for primary tumors and other metastases) to quantify the whole-body SSTR-expressing tumor volume (SRETVwb) and total lesion SSTR expression (TLSREwb). Patient survival was also recorded and analyzed. RESULTS: PET/CT images revealed heterogeneous uptake of 68Ga-DOTATATE at primary and metastatic sites. Progression-free (PFS) and overall survival (OS) were negatively correlated with the extent of liver or bone metastases (P < 0.05), but not significantly correlated with tumor grade or 18F-FDG PET/CT positivity. By the hybrid method, PFS was significantly shorter in patients with high SRETVwb, and OS was significantly shorter in those with high SRETVwb and TLSREwb (P < 0.05). However, when derived from method A or method B, neither SRETVwb nor TLSREwb could predict patient outcomes. CONCLUSION: Compared with other methods used in 68Ga-DOTATATE-avid stage IV NENs, our hybrid SUV thresholding method demonstrated robustness, with greater precision, reliability, and prognostic power.

18.
Eur Radiol ; 33(1): 615-626, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35751696

RESUMO

BACKGROUND: [18F]FDG imaging on total-body PET/CT (TB PET/CT) scanners, with improved sensitivity, offers new potentials for cancer diagnosis, staging, and radiation treatment planning. This consensus provides the protocols for clinical practices with a goal of paving the way for future studies with the total-body scanners in oncological [18F]FDG TB PET/CT imaging. METHODS: The consensus was summarized based on the published guidelines and peer-reviewed articles of TB PET/CT in the literature, along with the opinions of the experts from major research institutions with a total of 40,000 cases performed on the TB PET/CT scanners. RESULTS: This consensus describes the protocols for routine and dynamic [18F]FDG TB PET/CT scanning focusing on the reduction of imaging acquisition time and FDG injected activity, which may serve as a reference for research and clinic oncological PET/CT studies. CONCLUSION: This expert consensus focuses on the reduction of acquisition time and FDG injected activity with a TB PET/CT scanner, which may improve the patient throughput or reduce the radiation exposure in daily clinical oncologic imaging. KEY POINTS: • [18F]FDG-imaging protocols for oncological total-body PET/CT with reduced acquisition time or with different FDG activity levels have been summarized from multicenter studies. • Total-body PET/CT provides better image quality and improved diagnostic insights. • Clinical workflow and patient management have been improved.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Consenso , Tomografia por Emissão de Pósitrons/métodos , Tomógrafos Computadorizados , Compostos Radiofarmacêuticos/farmacologia
19.
Eur J Pediatr ; 182(12): 5519-5530, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37782352

RESUMO

Castleman disease (CD) is a rare lymphoproliferative disorder of undetermined etiology. Unicentric CD (UCD) and multicentric CD (MCD) are two phenotypes of CD diagnosed by the histopathology of lymph nodes. We attempted to describe a pediatric CD cohort to optimize the management of this disease. We reviewed the medical records of pediatric patients diagnosed with CD between April, 2004, and October, 2022, at the Children's Hospital of Fudan University. Prognosis information was collected in January, 2023, by telephone inquiry. Twenty-two patients with UCD and 2 patients with MCD were identified, all with hyaline vascular (HV) type. The median ages at diagnosis were 10.75 years (IQR 8, 12.81) for UCD and 14.42 years (IQR 13.42, 15.42) for MCD. The most common lesion location of UCD was the neck (9/22, 40.91%) and abdomen (9/22, 40.91%). Systematic symptoms occurred on 10/22 (45.45%) patients with UCD and 1/2 (50%) patients with MCD, and abnormal laboratory indexes were detected in both. Resection and biopsy were performed on all patients. One out of two patients with MCD also received rituximab for upfront therapy. After a median of 4 years (IQR 1.5, 6) of follow-up time, the overall survival was 100% and the complete remission rate in UCD was 63%. There was no relapse or progression. CONCLUSIONS: Our series demonstrated that HV-UCD was the most common type in children. Resection and biopsy were used for both deterministic diagnoses and treatments. Despite the high possibility to develop systematic inflammation, children with CD showed promising outcomes. WHAT IS KNOWN: • Castleman disease is a rare lymphoproliferative disorder with limited cohort studies, especially in pediatrics. • The ubiquity of delayed confirmations and misdiagnoses points to a lack of knowledge about etiology and characteristics, which is a prerequisite for novel therapeutics. WHAT IS NEW: • We retrospectively reviewed and analyzed the clinical and pathological symptoms, laboratory and imaging features, and treatment outcomes of a Chinese pediatric cohort with Castleman disease. • Our work may improve the recognition and optimize the management of this rare disease in children.


Assuntos
Hiperplasia do Linfonodo Gigante , Humanos , Criança , Hiperplasia do Linfonodo Gigante/diagnóstico , Hiperplasia do Linfonodo Gigante/terapia , Hiperplasia do Linfonodo Gigante/patologia , Estudos Retrospectivos , Linfonodos/patologia , Resultado do Tratamento , China
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(11): 1107-1112, 2023 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-37990453

RESUMO

OBJECTIVES: To study the efficacy and safety of Xiyanping injection through intramuscular injection for the treatment of acute bronchitis in children. METHODS: A prospective study was conducted from December 2021 to October 2022, including 78 children with acute bronchitis from three hospitals using a multicenter, randomized, parallel-controlled design. The participants were divided into a test group (conventional treatment plus Xiyanping injection; n=36) and a control group (conventional treatment alone; n=37) in a 1:1 ratio. Xiyanping injection was administered at a dose of 0.3 mL/(kg·d) (total daily dose ≤8 mL), twice daily via intramuscular injection, with a treatment duration of ≤4 days and a follow-up period of 7 days. The treatment efficacy and safety were compared between the two groups. RESULTS: The total effective rate on the 3rd day after treatment in the test group was significantly higher than that in the control group (P<0.05), while there was no significant difference in the total effective rate on the 5th day between the two groups (P>0.05). The rates of fever relief, cough relief, and lung rale relief in the test group on the 3rd day after treatment were higher than those in the control group (P<0.05). The cough relief rate on the 5th day after treatment in the test group was higher than that in the control group (P<0.05), while there was no significant difference in the fever relief rate and lung rale relief rate between the two groups (P>0.05). The cough relief time, daily cough relief time, and nocturnal cough relief time in the test group were significantly shorter than those in the control group (P<0.05), while there were no significant differences in the fever duration and lung rale relief time between the two groups (P>0.05). There was no significant difference in the incidence of adverse events between the two groups (P>0.05). CONCLUSIONS: The overall efficacy of combined routine treatment with intramuscular injection of Xiyanping injection in the treatment of acute bronchitis in children is superior to that of routine treatment alone, without an increase in the incidence of adverse reactions.


Assuntos
Bronquite , Tosse , Humanos , Criança , Injeções Intramusculares , Tosse/tratamento farmacológico , Estudos Prospectivos , Sons Respiratórios , Bronquite/tratamento farmacológico , Resultado do Tratamento
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