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1.
Front Immunol ; 15: 1336817, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601154

RESUMO

Introduction: Numerous observational studies have indicated that smoking is a substantial risk factor for esophageal cancer. However, there is a shortage of research that delves into the specific causal relationship and potential mediators between the two. Our study aims to validate the correlation between smoking-related traits and esophageal cancer while exploring the possible mediating effects of immune factors. Methods: Initially, we conducted bidirectional univariate Mendelian Randomization (MR) analyses to forecast the causal effects linking smoking-related traits and esophageal cancer. Subsequently, we employed a two-step MR analysis to scrutinize immune cell phenotypes that could mediate these effects. Finally, the coefficient product method was employed to determine the precise mediating impact. Additionally, we have refined our sensitivity analysis to ensure the reliability of the outcomes. Results: After analysis, Smoking status: Never had a significant negative association with the incidence of esophageal cancer (inverse-variance weighted (IVW) method, p=1.82e-05, OR=0.10, 95%CI=0.04~0.29). Ever smoked (IVW, p=1.49e-02, OR=4.31, 95%CI=1.33~13.94) and Current tobacco smoking (IVW, p=1.49e-02, OR=4.31, 95%CI=1.33~13.94) showed the promoting effect on the pathogenesis of esophageal cancer. Through further examination, researchers discovered 21 immune cell phenotypes that have a causal relationship with esophageal cancer. After careful screening, two immune cell phenotypes were found to have potential mediating effects. In particular, it was observed that in the case of the preventive effect of Smoking status: Never on esophageal cancer, the absolute count of CD62L plasmacytoid dendritic cells mediated a reduction of 4.21%, while the mediating effect of CD27 in CD20-CD38-B cells was -4.12%. In addition, sensitivity analyses did not reveal significant heterogeneity or level pleiotropy. Conclusion: The study provides new evidence for the causal relationship between smoking-related features and esophageal cancer and proposes immune factors with potential mediating effects. However, this finding needs to be further demonstrated by more extensive clinical studies.


Assuntos
Neoplasias Esofágicas , Fumar , Humanos , Fumar/efeitos adversos , Reprodutibilidade dos Testes , Fumar Tabaco , Neoplasias Esofágicas/genética , Fenótipo , Fatores Imunológicos
2.
Medicine (Baltimore) ; 103(8): e37175, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394482

RESUMO

Recent epidemiological research suggests a possible negative correlation between Helicobacter pylori infection and inflammatory bowel disease (IBD). However, conflicting studies have provided unclear evidence regarding these causal relationships. Therefore, recommending specific prevention and treatment strategies for H. pylori infection and IBD is challenging. We used various antibodies (anti-H. pylori IgG, VacA, and GroEl) related to H. pylori infection as indicators. We acquired relevant genetic variants from public databases within the Genome-wide Association Studies (GWAS) dataset using IBDs tool variables from 2 different GWAS datasets. We thoroughly examined the data and screened for IVs that fulfilled these criteria. Subsequently, Bidirectional Mendelian randomization (MR) was conducted to predict the potential causality between the 2. To ensure the accuracy and robustness of our results, we conducted a series of sensitivity analyses. Based on our comprehensive MR analysis, no potential causal relationship was observed between H. pylori infection and IBD. Across various methodologies, including IVW, MR-Egger, and weighted median, our findings showed P values > .05. The only exception was observed in the reverse MR analysis using the MR-Egger method, which yielded a P value of < .05. However, because the IVW method is considered the most statistically significant method for MR, and its P value was > .05, we do not believe that a potential causal relationship exists between them. Our sensitivity analysis did not suggest significant horizontal pleiotropism. Although heterogeneity was detected in the analysis of IBD (IIBDGC source) versus H. pylori GroEL antibody levels (MR-Egger, Qp = 0.038; IVW, Qp = 0.043), the results remained reliable because we selected IVW as a random-effects model in our MR analysis method. Based on our MR research, no direct correlation was observed between H. pylori infection and IBD risk. This implies that eradicating H. pylori may not provide substantial benefits in preventing or treating regional IBD, and vice versa. Nevertheless, the use of H. pylori serological index substitution has limitations, and further research using histological diagnosis and additional MR studies is required to comprehensively assess the link between H. pylori infection and IBD.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Doenças Inflamatórias Intestinais , Humanos , Estudo de Associação Genômica Ampla , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/genética , Análise da Randomização Mendeliana , Anticorpos Antibacterianos , Doenças Inflamatórias Intestinais/genética
3.
Environ Health ; 23(1): 21, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365736

RESUMO

BACKGROUND: While prenatal exposure to alkylphenols (APs) has been demonstrated to be associated with neurodevelopmental impairments in animals, the evidence from epidemiological studies remains limited and inconclusive. This study aimed to explore the link between AP exposure during pregnancy and the intelligence quotient (IQ) of preschool children. METHODS: A total of 221 mother-child pairs from the Guangxi Zhuang Birth Cohort were recruited. Nonylphenol (NP), 4-tert-octylphenol (4-T-OP), 4-n-nonylphenol (4-N-NP), and 4-n-octylphenol were measured in maternal serum in early pregnancy. Childhood IQ was evaluated by the Fourth Edition of Wechsler Preschool and Primary Scale of the Intelligence at 3 to 6 years of age. The impact of APs on childhood IQ were evaluated by generalized linear models (GLMs), restricted cubic spline (RCS), and Bayesian kernel machine regression (BKMR). RESULTS: In GLMs, prenatal exposure to NP and the second tertile of 4-T-OP exhibited an inverse association with full-scale IQ (FSIQ) (ß = -2.38; 95% CI: -4.59, -0.16) and working memory index (WMI) (ß = -5.24; 95% CI: -9.58, -0.89), respectively. Prenatal exposure to the third tertile of 4-N-NP showed a positive association with the fluid reasoning index (ß = 4.95; 95% CI: 1.14, 8.77) in total children, as well as in girls when stratified by sex. A U-shaped relationship between maternal 4-T-OP and WMI was noted in total children and girls by RCS (all P nonlinear < 0.05). The combined effect primarily driven by NP, of maternal AP mixtures at concentrations above the 50th percentile exhibited an inverse trend on FSIQ in total children and girls in BKMR. CONCLUSIONS: Prenatal exposure to various APs affects IQ in preschool children, and there may be nonmonotonic and sex-specific effects. Further investigation across the population is required to elucidate the potential neurotoxic effects of APs.


Assuntos
Fenóis , Efeitos Tardios da Exposição Pré-Natal , Masculino , Gravidez , Feminino , Humanos , Pré-Escolar , Criança , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Teorema de Bayes , China , Testes de Inteligência , Inteligência
4.
Ophthalmic Physiol Opt ; 44(1): 219-228, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37811684

RESUMO

PURPOSE: This study used three-dimensional (3D) modelling to investigate scleral profiles in myopic eyes and compare them with emmetropic eyes. METHODS: In this prospective observational study, the eyes of 151 participants were analysed using the corneoscleral profile module (CSP) of the Pentacam HR. Non-rotationally symmetrical ellipsoids were fitted to the anterior scleral sagittal height. Three radii were analysed, namely the nasal-temporal (Rx), superior-inferior (Ry) and anterior-posterior (Rz) orientations. Additionally, the area index (AI) and aspherical parameters (Qxy, Qxz and Qyz) of the anterior sclera-fitted ellipsoid (ASFE) were quantified. RESULTS: The findings showed an increase in Rx (-0.349 mm/D), Ry (-0.373 mm/D), Rz (-1.232 mm/D) and AI (-36.165 mm2 /D) with increasing myopia. From emmetropia to high myopia, the vertical and horizontal planes of the anterior sclera became increasingly prolate (emmetropia, Qxz: 0.02, Qyz: 0.01; low myopia, Qxz: -0.28, Qyz: -0.28; high myopia, Qxz: -0.41, Qyz: -0.43). There were no significant differences in the coronal plane across the three groups (H = 2.65, p = 0.27). The anterior scleral shape of high myopes in the horizontal and vertical planes was more prolate than that of emmetropes and low myopes (Qxz, high myopes vs. low myopes: p = 0.03, high myopes vs. emmetropes: p < 0.001; Qyz, high myopes vs. low myopes: p = 0.04, high myopes vs. emmetropes: p < 0.001). CONCLUSIONS: As the degree of myopia increased, non-uniform anterior scleral enlargement was observed. These findings provide a better understanding of the anterior segment with varying degrees of myopia.


Assuntos
Miopia , Fosmet , Humanos , Esclera , Miopia/diagnóstico , Emetropia , Estudos Prospectivos
5.
Ecotoxicol Environ Saf ; 267: 115665, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37951091

RESUMO

Exposure to bisphenols can affect bone mineral density (BMD) in animals and humans. However, the effects of maternal exposure to bisphenols during pregnancy on bone health in preschool children remain unknown. We aimed to assess the effects of prenatal exposure to single and multiple bisphenols on bone health in preschool children. A total of 230 mother-child pairs were included in this study. Generalized linear regression, restricted cubic spline (RCS), principal component analysis (PCA), and Bayesian kernel machine regression (BKMR) were utilized to assess the relationship between bisphenol levels and bone health in preschool children. Each natural log (Ln) unit increase in tetrabromobisphenol A was related to a 0.007 m/s (95 % CI: -0.015, 0.000) decrease in Ln-transformed speed of sound (SOS) among girls. Decreased BMD Z scores in preschool children were found only in the high bisphenol S exposure group (ß = -0.568; 95 % CI: -1.087, -0.050) in boys. The risk of low BMD (BMDL) was significantly higher in the middle-exposure group (OR = 4.695; 95 % CI: 1.143, 24.381) and high-exposure group of BPS (OR = 6.165, 95 % CI: 1.445, 33.789) compared with the low-exposure group in boys. In girls, the risk of BMDL decreased with increasing bisphenol A concentration (OR = 0.413, 95 % CI: 0.215, 0.721). RCS analysis revealed a U-shaped nonlinear correlation between BPB concentration and BMDL in girls (P-overall = 0.011, P-nonlinear = 0.009). In PCA, a U-shaped dose-response relationship was found between PC2 and the risk of BMDL (P-overall = 0.048, P-nonlinear = 0.032), and a significant association was only noted in girls when stratified by sex. The BKMR model revealed a horizontal S-shaped curve relationship between bisphenol mixtures and BMDL in girls. The results indicated that prenatal exposure to single and mixed bisphenols can affect BMD in preschool children, exerting nonmonotonic and child sex-specific effects.


Assuntos
Densidade Óssea , Efeitos Tardios da Exposição Pré-Natal , Animais , Masculino , Feminino , Gravidez , Humanos , Pré-Escolar , Teorema de Bayes , Estudos Prospectivos
6.
Adv Healthc Mater ; 12(26): e2300882, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37539730

RESUMO

The application of nanomaterials in healthcare has emerged as a promising strategy due to their unique structural diversity, surface properties, and compositional diversity. In particular, nanomaterials have found a significant role in improving drug delivery and inhibiting the growth and metastasis of tumor cells. Moreover, recent studies have highlighted their potential in modulating the tumor microenvironment (TME) and enhancing the activity of immune cells to improve tumor therapy efficacy. Various types of nanomaterials are currently utilized as drug carriers, immunosuppressants, immune activators, immunoassay reagents, and more for tumor immunotherapy. Necessarily, nanomaterials used for tumor immunotherapy can be grouped into two categories: organic and inorganic nanomaterials. Though both have shown the ability to achieve the purpose of tumor immunotherapy, their composition and structural properties result in differences in their mechanisms and modes of action. Organic nanomaterials can be further divided into organic polymers, cell membranes, nanoemulsion-modified, and hydrogel forms. At the same time, inorganic nanomaterials can be broadly classified as nonmetallic and metallic nanomaterials. The current work aims to explore the mechanisms of action of these different types of nanomaterials and their prospects for promoting tumor immunotherapy.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Imunoterapia , Microambiente Tumoral , Neoplasias/tratamento farmacológico
7.
Sci Rep ; 13(1): 12096, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495633

RESUMO

The cisterna magna has been defined as the space between the inferior margin of the cerebellar vermis to the level of the foramen magnum, while an enlarged dorsal subarachnoid space at the occipito-cervical junction extending from the foramen magnum to the upper border of the axis (C2) is still ignored. Recently, the myodural bridge complex is proved to drive the cerebral spinal fluid flowing via this region, we therefore introduce the "occipito-atlantal cistern (OAC)" to better describe the subarachnoid space and provide a detailed rationale. The present study utilized several methods, including MRI, gross anatomical dissection, P45 sheet plastination, and three-dimensional visualization. OAC was observed to be an enlarge subarachnoid space, extending from the foramen magnum to the level of the C2. In the median sagittal plane, OAC was a funnel shape and its anteroposterior dimensions were 15.92 ± 4.20 mm at the level of the C0, 4.49 ± 1.25 mm at the level of the posterior arch of the C1, and 2.88 ± 0.77 mm at the level of the arch of the C2, respectively. In the median sagittal plane, the spino-dural angle of the OAC was calculated to be 35.10 ± 6.91°, and the area of OAC was calculated to be 232.28 ± 71.02 mm2. The present study provides OAC is a subarachnoid space independent from the cisterna magna. Because of its distinctive anatomy, as well as theoretical and clinical significance, OAC deserves its own name.


Assuntos
Forame Magno , Espaço Subaracnóideo , Espaço Subaracnóideo/diagnóstico por imagem , Forame Magno/diagnóstico por imagem , Pescoço , Medula Espinal , Cisterna Magna/diagnóstico por imagem
8.
Front Pharmacol ; 14: 1288492, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38178862

RESUMO

Background: ARLs, which are a class of small GTP-binding proteins, play a crucial role in facilitating tumor tumorigenesis and development. ARL4C, a vital member of the ARLs family, has been implicated in the progression of tumors, metastatic dissemination, and development of resistance to therapeutic drugs. Nevertheless, the precise functional mechanisms of ARL4C concerning tumor prognosis and immunotherapy drug susceptibility remain elusive. Methods: By combining the GTEx and TCGA databases, the presence of ARL4C was examined in 33 various types of cancer. Immunohistochemistry and immunofluorescence staining techniques were utilized to confirm the expression of ARL4C in particular tumor tissues. Furthermore, the ESTIMATE algorithm and TIMER2.0 database were utilized to analyze the tumor microenvironment and immune infiltration associated with ARL4C. The TISCH platform facilitated the utilization of single-cell RNA-seq datasets for further analysis. ARL4C-related immune escape was investigated using the TISMO tool. Lastly, drug sensitivity analysis was conducted to assess the sensitivity of different types of tumors to compounds based on the varying levels of ARL4C expression. Results: The study found that ARL4C was highly expressed in 23 different types of cancer. Moreover, the presence of high ARL4C expression was found to be associated with a poor prognosis in BLCA, COAD, KIRP, LGG, and UCEC. Notably, ARL4C was also expressed in immune cells, and its high expression was found to be correlated with cancer immune activation. Most importantly, the drug sensitivity analysis revealed a positive correlation between ARL4C expression and the heightened sensitivity of tumors to Staurosporine, Midostaurin, and Nelarabine. Conclusion: The findings from our study indicate that the expression level of ARL4C may exert an influence on cancer development, prognosis, and susceptibility to immunotherapy drugs. In addition, the involvement of ARL4C in the tumor immune microenvironment has expanded the concept of ARL4C-targeted immunotherapy.

9.
J Nanobiotechnology ; 20(1): 484, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384524

RESUMO

With the economy's globalization and the population's aging, cancer has become the leading cause of death in most countries. While imposing a considerable burden on society, the high morbidity and mortality rates have continuously prompted researchers to develop new oncology treatment options. Anti-tumor regimens have evolved from early single surgical treatment to combined (or not) chemoradiotherapy and then to the current stage of tumor immunotherapy. Tumor immunotherapy has undoubtedly pulled some patients back from the death. However, this strategy of activating or boosting the body's immune system hardly benefits most patients. It is limited by low bioavailability, low response rate and severe side effects. Thankfully, the rapid development of nanotechnology has broken through the bottleneck problem of anti-tumor immunotherapy. Multifunctional nanomaterials can not only kill tumors by combining anti-tumor drugs but also can be designed to enhance the body's immunity and thus achieve a multi-treatment effect. It is worth noting that the variety of nanomaterials, their modifiability, and the diversity of combinations allow them to shine in antitumor immunotherapy. In this paper, several nanobiotics commonly used in tumor immunotherapy at this stage are discussed, and they activate or enhance the body's immunity with their unique advantages. In conclusion, we reviewed recent advances in tumor immunotherapy based on nanomaterials, such as biological cell membrane modification, self-assembly, mesoporous, metal and hydrogels, to explore new directions and strategies for tumor immunotherapy.


Assuntos
Antineoplásicos , Nanoestruturas , Neoplasias , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico , Nanotecnologia , Nanoestruturas/uso terapêutico , Antineoplásicos/uso terapêutico
10.
Front Immunol ; 13: 979469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072591

RESUMO

Cancer represents the leading global driver of death and is recognized as a critical obstacle to increasing life expectancy. In recent years, with the development of precision medicine, significant progress has been made in cancer treatment. Among them, various therapies developed with the help of the immune system have succeeded in clinical treatment, recognizing and killing cancer cells by stimulating or enhancing the body's intrinsic immune system. However, low response rates and serious adverse effects, among others, have limited the use of immunotherapy. It also poses problems such as drug resistance and hyper-progression. Fortunately, thanks to the rapid development of nanotechnology, engineered multifunctional nanomaterials and biomaterials have brought breakthroughs in cancer immunotherapy. Unlike conventional cancer immunotherapy, nanomaterials can be rationally designed to trigger specific tumor-killing effects. Simultaneously, improved infiltration of immune cells into metastatic lesions enhances the efficiency of antigen submission and induces a sustained immune reaction. Such a strategy directly reverses the immunological condition of the primary tumor, arrests metastasis and inhibits tumor recurrence through postoperative immunotherapy. This paper discusses several types of nanoscale biomaterials for cancer immunotherapy, and they activate the immune system through material-specific advantages to provide novel therapeutic strategies. In summary, this article will review the latest advances in tumor immunotherapy based on self-assembled, mesoporous, cell membrane modified, metallic, and hydrogel nanomaterials to explore diverse tumor therapies.


Assuntos
Nanoestruturas , Neoplasias , Materiais Biocompatíveis , Humanos , Sistema Imunitário/patologia , Imunoterapia
11.
Micromachines (Basel) ; 12(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34945410

RESUMO

Radio frequency identification technology (RFID) has empowered a wide variety of automation industries. Aiming at the current light-weight RFID encryption scheme with limited information protection methods, combined with the physical unclonable function (PUF) composed of resistive random access memory (RRAM), a new type of high-efficiency reconfigurable strong PUF circuit structure is proposed in this paper. Experimental results show that the proposed PUF shows an almost ideal value (50%) of inter-chip hamming distance (HD) (µ/σ = 0.5001/0.0340) among 1000 PUF keys, and intra-chip HD results are very close to the ideal value (0). The bit error rate (BER) is as low as 3.8×10-6 across one million challenges. Based on the RRAM PUF, we propose and implement a light weight RFID authentication protocol. By virtue of RRAM's model ability, the protocol replaces the One-way Hash Function with a response chain mutual encryption algorithm. The results of test and analysis show that the protocol can effectively resist multiple threats such as physical attacks, replay attacks, tracking attacks and asynchronous attacks, and has good stability. At the same time, based on RRAM's unique resistance variability, PUF also has the advantage of being reconfigurable, providing good security for RFID tags.

12.
Animals (Basel) ; 11(11)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34827866

RESUMO

Keel bone damage negatively affects the welfare, production performance, egg quality, and mobility of laying hens. This study aimed to investigate whether abnormal bone metabolism causes keel bone damage in laying hens. Eighty Hy-line Brown laying hens were housed in eight furnished cages with 10 birds per cage and studied from 18 to 29 weeks of age (WOA). Accordingly, keel bone status was assessed at 18, 22, 25, and 29 WOA using the X-ray method, and the serum samples of laying hens with normal keel (NK), deviated keel (DK), and fractured keel (FK) that occurred at 29 WOA were collected across all the time-points. Subsequently, the serum samples were used to measure markers related to the metabolism of Ca and P and activities of osteoblast and osteoclast. The results showed that FK laying hens had lighter bodyweight than NK and DK birds throughout the trial (p < 0.05), while the keel bone length and weight were not different in NK, DK, and FK hens at 29 WOA (p > 0.05). Moreover, bone hematoxylin and eosin (H&E) staining and tartrate-resistant acid phosphatase (TRAP) staining indicated that damaged keel bone had evident pathological changes. In the FK hens, serum P level was reduced but serum 1,25-dihydroxy-vitamin D3 (1,25-(OH)2D3) and 25-hydroxyvitamin D3 (25-OHD3) levels were elevated compared to NK hens (p < 0.05). Additionally, DK hens had higher levels of serum 1,25-(OH)2D3, parathyroid hormone (PTH) and calcitonin (CT), and lower level of serum 25-OHD3 than the NK birds (p < 0.05). Furthermore, serum alkaline phosphatase (ALP), osteocalcin (OC), osteoprotegerin (OPG), TRAP, and corticosterone (CORT) levels were elevated in DK and FK hens compared to NK hens (p < 0.05). The levels of serum Ca, P, PTH, ALP, TRAP, OPG, OC, and CORT in laying hens fluctuated with the age of the birds. Generally, the results of this study indicate that keel bone damage, especially fractures, could be associated with abnormal bone metabolism in laying hens.

13.
ACS Appl Mater Interfaces ; 13(44): 52374-52384, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34714617

RESUMO

Bladder cancer (BCa) is the most costly solid tumor owing to its high recurrence. Relapsed cancer is known to acquire chemoresistant features after standard intravesical chemotherapy. This cancer state is vulnerable to ferroptosis, which occurs when lipid peroxides generated by iron metabolism accumulate to lethal levels. Increasing the labile iron pool (LIP) by iron oxide nanoparticles (IONPs) promises to inhibit chemoresistant BCa (CRBCa), but systemically administered IONPs do not sufficiently accumulate at the tumor site. Therefore, their efficacy is weakened. Here, we present a three-tier delivery strategy through a mucoadhesive hydrogel platform conveying hyaluronic acid-coated IONPs (IONP-HA). When instilled, the hydrogel platform first adhered to the interface of the tumor surface, sustainably releasing IONP-HA. Subsequently, the tumor stiffness and interstitial fluid pressure were reduced by photothermal therapy, promoting IONP-HA diffusion into the deep cancer tissue. As CRBCa expressed high levels of CD44, the last delivery tier was achieved through antibody-mediated endocytosis to increase the LIP, ultimately inducing ferroptosis. This three-tiered strategy delivered the IONPs stepwise from anatomical to cellular levels and increased the iron content by up to 50-fold from that of systematic administration, which presents a potential regimen for CRBCa.

14.
Patterns (N Y) ; 2(5): 100243, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34036288

RESUMO

Microstructural evolution is a key aspect of understanding and exploiting the processing-structure-property relationship of materials. Modeling microstructure evolution usually relies on coarse-grained simulations with evolution principles described by partial differential equations (PDEs). Here we demonstrate that convolutional recurrent neural networks can learn the underlying physical rules and replace PDE-based simulations in the prediction of microstructure phenomena. Neural nets are trained by self-supervised learning with image sequences from simulations of several common processes, including plane-wave propagation, grain growth, spinodal decomposition, and dendritic crystal growth. The trained networks can accurately predict both short-term local dynamics and long-term statistical properties of microstructures assessed herein and are capable of extrapolating beyond the training datasets in spatiotemporal domains and configurational and parametric spaces. Such a data-driven approach offers significant advantages over PDE-based simulations in time-stepping efficiency and offers a useful alternative, especially when the material parameters or governing PDEs are not well determined.

15.
Sci Total Environ ; 778: 146295, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721637

RESUMO

The adsorption treatment of ammonium-containing wastewater has attracted significant global attention. Most enhanced adsorption methods employ chemical modification, and there are few reports on physical activation. We present a physical activation to explore whether physical ultrasound may enhance the adsorption performance and comprehensive utilisation of a new forestry waste, Caragana korshinskii was used as a feedstock to prepare activated biochar (ACB) by controlling the pyrolysis temperatures and ultrasound parameters. The optimal parameters were determined via batch adsorption of NH4+, and the adsorption characteristics were assessed by 8 kinds of models and influence experiments. Moreover, the physicochemical properties of ACB during the pyrolysis process were investigated, and the ultrasonic activation and adsorption mechanisms were discussed using multiple characterisation techniques. Additionally, the cost analysis, the safety of the ultrasonic process and disposal method also were evaluated. The results showed that the ultrasonic activation significantly enhanced the NH4+ adsorption efficiency of biochar by approximately 5 times. ACB exhibited the best performance at 500 °C with an ultrasonic activation time of 480 min, frequency of 45 kHz, and power of 700 W. The ultrasonic activation reduced the biochar ash and induced pore formation, which increased the specific surface area through cavitation corrosion and micro-acoustic flow mechanism. The NH4+ adsorption mechanisms comprised physicochemical processes, of which physical adsorption was dominant. The preparation cost of 1 kg ACB was about 0.42 US dollar, and no secondary pollution occurred in the activation process. The findings prove that ultrasonic technology is efficient and convenient for enhancing biochar adsorption performance, and thus is suitable for industrial applications and promotion.


Assuntos
Compostos de Amônio , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Agricultura Florestal , Ultrassom
16.
Eur J Gastroenterol Hepatol ; 32(3): 401-405, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31356372

RESUMO

BACKGROUND AND AIM: Cirrhotic patients with gastroesophageal varices and non-tumoral portal vein thrombosis have a higher risk of re-bleeding and poor prognosis. This study aimed to analyze inflammatory biomarkers and thromboelastography in cirrhotic patients with portal vein thrombosis. METHODS: A total of 385 consecutive cirrhotic patients with gastroesophageal varices were prospectively enrolled between 1 December 2016, and 31 August 2017. Of these, 231 were eligible for analysis and were divided into portal vein thrombosis (n = 103) and non-portal vein thrombosis (n = 128) groups based on computerized tomography angiography findings. RESULTS: Patients with portal vein thrombosis generally had higher Child-Pugh scores than those without portal vein thrombosis (6.38 ± 0.12 vs. 5.81 ± 0.09, P < 0.001). The serum albumin levels were significantly lower in patients with portal vein thrombosis (35.90 ± 0.52 vs. 38.52 ± 0.43, P < 0.001). The portal vein thrombosis group had significant higher serum levels of interleukin 6 [4.85 (3.15-6.99) vs. 3.09 (2.06-5.20) pg/ml, P < 0.001] and tumor necrosis factor alpha [10.70 (7.60-15.20) vs. 9.07 (7.03-11.60) pg/ml, P = 0.020]. The interleukin 6 level was 2.5-fold higher in patients with portal vein thrombosis (adjusted odds ratio: 2.574; 95% confidential interval: 1.248-5.310). Thromboelastography showed that TEG-R, the reaction time, was significantly lower in the portal vein thrombosis group [5.20 (4.80-6.30) vs. 6.00 (5.20-6.95), P = 0.009], indicating enhanced coagulation activity. CONCLUSION: This study confirmed the important role of systemic inflammation in portal vein thrombosis. Interleukin 6, an important inflammatory cytokine, is independently associated with portal vein thrombosis. The correlation between the interleukin 6 level and portal vein thrombosis requires further investigation.


Assuntos
Varizes Esofágicas e Gástricas , Varizes , Trombose Venosa , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Humanos , Inflamação/patologia , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Varizes/patologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Trombose Venosa/patologia
17.
Sci Total Environ ; 699: 134223, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31522055

RESUMO

Biochar is beneficial for soil amendment, but further research is still required on changes in its physicochemical properties during aging, especially in oxygen-containing functional groups and associated adsorption behaviors. Here, we used two different biochars, apple tree branch biochar and maize stalk biochar, and simulated the aging process by using freeze-thaw cycles, dry-wet cycles, and chemical oxidation methods. We investigated the changes in the physicochemical properties and Pb adsorption behavior of the biochars before and after aging treatments. The characterization results showed that the biochar surface structure changed after aging treatments. In general, the specific surface areas (SSAs) of the two biochars increased after chemical oxidation treatment but decreased after the other two treatments. The elemental content analyses indicated a decrease in the C content and increase in O content after artificial aging. In addition, the content of oxygen-containing functional groups in most biochars is increasing after treatment. The increase or decrease in SSA resulted in an increase or decrease in adsorption sites, respectively, thereby enhancing or reducing the adsorption capacity of the biochar. Furthermore, oxygen-containing functional groups enhanced the Pb adsorption capacity of biochar by complexation of free carboxyl and hydroxyl functional groups with Pb. Our research indicated that aging can lead to changes in the Pb adsorption capacity of biochar and that these changes vary depending on the type of aging and biochar. Our results will help to provide a better understanding of the changes in physicochemical properties and Pb adsorption capacity of biochar during the aging process in soil toward making full use of biochar for soil amendment.


Assuntos
Carvão Vegetal/química , Chumbo/química , Poluentes do Solo/química , Adsorção , Oxirredução , Solo/química
18.
Biomed Res Int ; 2019: 9673162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781658

RESUMO

Background and aims. This study aimed to detect exhaled nitric oxide (eNO) level in cirrhotic patients and explore the correlation between eNO levels and the severity of cirrhosis. Methods. Patients were enrolled to analyze the relationship of eNO with noncirrhosis, cirrhosis, and complications of decompensated cirrhosis. We explored the potential predictive values of eNO in different states of cirrhosis. Results. The eNO levels were significantly increased in cirrhotic patients compared with noncirrhotic patients (14 (10-18) vs 8 (6-13) ppb, P < 0.001). The eNO level was increased in those with ascites (15 (14-22) vs 13 (10-18) ppb, P=0.026), with portal vein thrombosis (19.5 (11.75-22) vs 13.5 (10-17) ppb, P=0.032), or with the mucosal red-color sign of esophageal and gastric varices (EGV) (16.5 (10-21.75) vs 13 (10-14.75) ppb, P=0.041). Among cirrhotic patients undergoing hepatic venous pressure gradient (HVPG) measurement, the eNO level was significantly increased in the high-HVPG group (HVPG >12 mm Hg) compared with the low-HVPG group (6 mm Hg ≤ HVPG ≤ 12 mm Hg) (15 (11.75-19.25) vs 10 (8-14) ppb, P=0.011). Conclusions. The eNO level was increased in cirrhotic patients, especially in those complicated with ascites, portal vein thrombosis, mucosal red-color sign of varices, and high HVPG.


Assuntos
Varizes Esofágicas e Gástricas/complicações , Cirrose Hepática/complicações , Óxido Nítrico/análise , Trombose/complicações , Adulto , Ascite/fisiopatologia , Varizes Esofágicas e Gástricas/patologia , Varizes Esofágicas e Gástricas/fisiopatologia , Expiração , Feminino , Humanos , Fígado/fisiopatologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Veia Porta/patologia , Veia Porta/fisiologia , Veia Porta/fisiopatologia , Trombose/fisiopatologia , Pressão Venosa
19.
Nature ; 575(7781): 175-179, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659340

RESUMO

Supramolecular soft crystals are periodic structures that are formed by the hierarchical assembly of complex constituents, and occur in a broad variety of 'soft-matter' systems1. Such soft crystals exhibit many of the basic features (such as three-dimensional lattices and space groups) and properties (such as band structure and wave propagation) of their 'hard-matter' atomic solid counterparts, owing to the generic symmetry-based principles that underlie both2,3. 'Mesoatomic' building blocks of soft-matter crystals consist of groups of molecules, whose sub-unit-cell configurations couple strongly to supra-unit-scale symmetry. As yet, high-fidelity experimental techniques for characterizing the detailed local structure of soft matter and, in particular, for quantifying the effects of multiscale reconfigurability are quite limited. Here, by applying slice-and-view microscopy to reconstruct the micrometre-scale domain morphology of a solution-cast block copolymer double gyroid over large specimen volumes, we unambiguously characterize its supra-unit and sub-unit cell morphology. Our multiscale analysis reveals a qualitative and underappreciated distinction between this double-gyroid soft crystal and hard crystals in terms of their structural relaxations in response to forces-namely a non-affine mode of sub-unit-cell symmetry breaking that is coherently maintained over large multicell dimensions. Subject to inevitable stresses during crystal growth, the relatively soft strut lengths and diameters of the double-gyroid network can easily accommodate deformation, while the angular geometry is stiff, maintaining local correlations even under strong symmetry-breaking distortions. These features contrast sharply with the rigid lengths and bendable angles of hard crystals.

20.
J Am Chem Soc ; 138(45): 14852-14855, 2016 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-27794594

RESUMO

We report the dramatic triggering of structural order in a Zr(IV)-based metal-organic framework (MOF) through docking of HgCl2 guests. Although as-made crystals were unsuitable for single crystal X-ray diffraction (SCXRD), with diffraction limited to low angles well below atomic resolution due to intrinsic structural disorder, permeation of HgCl2 not only leaves the crystals intact but also resulted in fully resolved backbone as well as thioether side groups. The crystal structure revealed elaborate HgCl2-thioether aggregates nested within the host octahedra to form a hierarchical, multifunctional net. The chelating thioether groups also promote Hg(II) removal from water, while the trapped Hg(II) can be easily extricated by 2-mercaptoethanol to reactivate the MOF sorbent.

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