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1.
Small ; : e2311478, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396159

RESUMO

Mg3 Sb2 -based alloys are attracting increasing attention due to the excellent room temperature thermoelectric properties. However, due to the presence and easy segregation of charged Mg vacancies, the carrier mobility in Mg3 Sb2 -based alloys is always severely compromised that significantly restricts the room temperature performance. General vacancy compensation strategies cannot synergistically optimize the complicated Mg3 Sb2 structures involving both interior and boundary scattering. Herein, due to the multi-functional doping effect of Nb, the electron scattering inside and across grains is significantly suppressed by inhibiting the accumulation of Mg vacancies, and leading to a smooth transmission channel of electrons. The increased Mg vacancies migration barrier and optimized interface potential are also confirmed theoretically and experimentally, respectively. As a result, a leading room temperature zT of 1.02 is achieved. This work reveals the multi-functional doping effect as an efficient approach in improving room temperature thermoelectric performance in complicated defect/interface associated Mg3 Sb2 -based alloys.

2.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33941684

RESUMO

Immune checkpoint inhibitors represent some of the most important cancer treatments developed in the last 20 y. However, existing immunotherapy approaches benefit only a minority of patients. Here, we provide evidence that the aryl hydrocarbon receptor (AhR) is a central player in the regulation of multiple immune checkpoints in oral squamous cell carcinoma (OSCC). Orthotopic transplant of mouse OSCC cells from which the AhR has been deleted (MOC1AhR-KO) results, within 1 wk, in the growth of small tumors that are then completely rejected within 2 wk, concomitant with an increase in activated T cells in tumor-draining lymph nodes (tdLNs) and T cell signaling within the tumor. By 2 wk, AhR+ control cells (MOC1Cas9), but not MOC1AhR-KO cells up-regulate exhaustion pathways in the tumor-infiltrating T cells and expression of checkpoint molecules on CD4+ T cells (PD-1, CTLA4, Lag3, and CD39) and macrophages, dendritic cells, and Ly6G+ myeloid cells (PD-L1 and CD39) in tdLNs. Notably, MOC1AhR-KO cell transplant renders mice 100% immune to later challenge with wild-type tumors. Analysis of altered signaling pathways within MOC1AhR-KO cells shows that the AhR controls baseline and IFNγ-induced Ido and PD-L1 expression, the latter of which occurs through direct transcriptional control. These observations 1) confirm the importance of malignant cell AhR in suppression of tumor immunity, 2) demonstrate the involvement of the AhR in IFNγ control of PD-L1 and IDO expression in the cancer context, and 3) suggest that the AhR is a viable target for modulation of multiple immune checkpoints.


Assuntos
Carcinoma de Células Escamosas/imunologia , Imunidade , Neoplasias Bucais/imunologia , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Animais , Antígenos CD , Antígenos Ly , Antígeno B7-H1 , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Linfócitos T CD4-Positivos , Antígeno CTLA-4 , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Dioxinas , Proteínas de Checkpoint Imunológico , Imunoterapia/métodos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias Bucais/patologia , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Linfócitos T/imunologia , Proteína do Gene 3 de Ativação de Linfócitos
3.
J Clin Immunol ; 43(4): 835-845, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807221

RESUMO

PURPOSE: Deficiency of adenosine deaminase 2 (DADA2), an autosomal recessive autoinflammatory disorder caused by biallelic loss-of-function variants in adenosine deaminase 2 (ADA2), has not been systemically investigated in Chinese population yet. We aim to further characterize DADA2 cases in China. METHODS: A retrospective analysis of patients with DADA2 identified through whole exome sequencing (WES) at seventeen rheumatology centers across China was conducted. Clinical characteristics, laboratory findings, genotype, and treatment response were analyzed. RESULTS: Thirty patients with DADA2 were enrolled between January 2015 and December 2021. Adenosine deaminase 2 enzymatic activity was low in all tested cases to confirm pathogenicity. Median age of disease presentation was 4.3 years and the median age at diagnosis was 7.8 years. All but one patient presented during childhood and two subjects died from complications of their disease. The patients most commonly presented with systemic inflammation (92.9%), vasculitis (86.7%), and hypogammaglobinemia (73.3%) while one patient presented with bone marrow failure (BMF) with variable cytopenia. Twenty-three (76.7%) patients were treated with TNF inhibitors (TNFi), while two (6.7%) underwent hematopoietic stem cell transplantation (HSCT). They all achieved clinical remission. A total of thirty-nine ADA2 causative variants were identified, six of which were novel. CONCLUSION: To establish early diagnosis and improve clinical outcomes, genetic screening and/or testing of ADA2 enzymatic activity should be performed in patients with suspected clinical features. TNFi is considered as first line treatment for those with vascular phenotypes. HSCT may be beneficial for those with hematological disease or in those who are refractory to TNFi.


Assuntos
Adenosina Desaminase , Peptídeos e Proteínas de Sinalização Intercelular , Humanos , Adenosina Desaminase/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Estudos de Coortes , Estudos Retrospectivos , Mutação
4.
Plant Physiol ; 190(3): 1941-1959, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35736512

RESUMO

Perception of pathogen-associated molecular patterns (PAMPs) triggers mitogen-activated protein (MAP) kinase 4 (MPK4)-mediated phosphorylation and induces downstream transcriptional reprogramming, but the mechanisms of the MPK4 defense pathway are poorly understood. Here, we showed that phosphorylation-mediated inactivation of the CCCH protein C3H14 by MPK4 positively regulates the immune response in Arabidopsis (Arabidopsis thaliana). Compared with wild-type plants, loss-of-function mutations in C3H14 and its paralog C3H15 resulted in enhanced defense against Pst DC3000 in infected leaves and the development of systemic acquired resistance (SAR), whereas C3H14 or C3H15 overexpression enhanced susceptibility to this pathogen and failed to induce SAR. The functions of C3H14 in PAMP-triggered immunity (PTI) and SAR were dependent on MPK4-mediated phosphorylation. Challenge with Pst DC3000 or the flagellin peptide flg22 enhanced the phosphorylation of C3H14 by MPK4 in the cytoplasm, relieving C3H14-inhibited expression of PTI-related genes and attenuating C3H14-activated expression of its targets NIM1-INTERACTING1 (NIMIN1) and NIMIN2, two negative regulators of SAR. Salicylic acid (SA) affected the MPK4-C3H14-NIMIN1/2 cascades in immunity, but SA signaling mediated by the C3H14-NIMIN1/2 cascades was independent of MPK4 phosphorylation. Our study suggests that C3H14 might be a negative component of the MPK4 defense signaling pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Fosforilação , Imunidade Vegetal/genética , Pseudomonas syringae/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ácido Salicílico/metabolismo
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(2): 143-147, 2021 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33627208

RESUMO

OBJECTIVE: To study the clinical features of children with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome, a polygenic and multifactorial autoinflammatory disease with unknown pathogenesis. METHODS: A retrospective analysis was performed on the medical data of 13 children with PFAPA syndrome. RESULTS: All 13 children had disease onset within the age of 3 years, with a mean age of onset of (14±10) months. They all had periodic fever, with 8-18 attacks each year. The mean interictal period of fever was (30±5) days. Pharyngitis, cervical adenitis, and aphthous stomatitis were the three cardinal symptoms, with incidence rates of 100% (13/13), 85% (11/13), and 38% (5/13) respectively. There were increases in white blood cells, C-reactive protein, and erythrocyte sedimentation rate during fever. Of all the 13 children, 6 underwent whole exome sequencing and 7 underwent panel gene detection for autoinflammatory disease, and the results showed single heterozygous mutations in the MEFV gene in 6 children (46%). Recurrent fever in all children gradually returned to normal without antibiotics. Ten children were treated with a single dose of glucocorticoids, and fever was relieved after treatment. Of all the children, 4 were treated with cimetidine, among whom 2 had response; 4 children were treated with colchicine, among whom 2 had response and 2 were withdrawn from the drug due to adverse reactions. Tonsillectomy was performed for 2 children, among whom 1 was followed up for 3 years without recurrence and 1 still had recurrence. CONCLUSIONS: For children with unexplained periodic fever with early onset accompanied by pharyngitis, cervical adenitis, aphthous stomatitis, elevated inflammatory indices, and good response to glucocorticoids, PFAPA syndrome should be considered. This disorder has good prognosis, and early diagnosis can avoid the long-term repeated use of antibiotics.


Assuntos
Linfadenite , Faringite , Estomatite Aftosa , Criança , Pré-Escolar , Febre/etiologia , Humanos , Lactente , Linfadenite/diagnóstico , Faringite/diagnóstico , Faringite/tratamento farmacológico , Pirina , Estudos Retrospectivos , Estomatite Aftosa/diagnóstico , Estomatite Aftosa/tratamento farmacológico , Estomatite Aftosa/genética
6.
Int J Mol Sci ; 22(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396563

RESUMO

For decades, the aryl hydrocarbon receptor (AHR) was studied for its role in environmental chemical toxicity i.e., as a quirk of nature and a mediator of unintended consequences of human pollution. During that period, it was not certain that the AHR had a "normal" physiological function. However, the ongoing accumulation of data from an ever-expanding variety of studies on cancer, cancer immunity, autoimmunity, organ development, and other areas bears witness to a staggering array of AHR-controlled normal and pathological activities. The objective of this review is to discuss how the AHR has gone from a likely contributor to genotoxic environmental carcinogen-induced cancer to a master regulator of malignant cell progression and cancer aggression. Particular focus is placed on the association between AHR activity and poor cancer outcomes, feedback loops that control chronic AHR activity in cancer, and the role of chronically active AHR in driving cancer cell invasion, migration, cancer stem cell characteristics, and survival.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias/patologia , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Humanos , Neoplasias/metabolismo , Receptores de Hidrocarboneto Arílico/genética
7.
Proc Natl Acad Sci U S A ; 108(45): E1035-44, 2011 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-21969568

RESUMO

Chemokine receptor CCR10 is expressed by all intestinal IgA-producing plasma cells and is suggested to play an important role in positioning these cells in the lamina propria for proper IgA production to maintain intestinal homeostasis and protect against infection. However, interfering with CCR10 or its ligand did not impair intestinal IgA production under homeostatic conditions or during infection, and the in vivo function of CCR10 in the intestinal IgA response remains unknown. We found that an enhanced generation of IgA(+) cells in isolated lymphoid follicles of intestines offset defective intestinal migration of IgA(+) cells in CCR10-KO mice, resulting in the apparently normal IgA production under homeostatic conditions and in primary response to pathogen infection. However, the compensatorily generated IgA(+) cells in CCR10-KO mice carried fewer hypermutations in their Ig heavy chain alleles than those of WT mice, indicating that their IgA repertoires are qualitatively different, which might impact the intestinal homeostasis of microflora. In addition, CCR10-deficient long-lived IgA-producing plasma cells and IgA(+) memory B cells generated against the pathogen infection could not be maintained properly in intestines. Consequently, IgA memory responses to the pathogen reinfection were severely impaired in CCR10-KO mice. These findings elucidate critical roles of CCR10 in regulating the intestinal IgA response and memory maintenance and could help in design of vaccines against intestinal and possibly other mucosal pathogens.


Assuntos
Imunoglobulina A/imunologia , Memória Imunológica , Intestino Grosso/imunologia , Intestino Delgado/imunologia , Receptores CCR10/fisiologia , Animais , Infecções Bacterianas/imunologia , Homeostase , Imunoglobulina A/biossíntese , Tecido Linfoide/imunologia , Camundongos , Camundongos Knockout , Mutação , Receptores CCR10/genética , Linfócitos T/imunologia
8.
Front Immunol ; 15: 1348189, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590525

RESUMO

Older patients with cancer, particularly those over 75 years of age, often experience poorer clinical outcomes compared to younger patients. This can be attributed to age-related comorbidities, weakened immune function, and reduced tolerance to treatment-related adverse effects. In the immune checkpoint inhibitors (ICI) era, age has emerged as an influential factor impacting the discovery of predictive biomarkers for ICI treatment. These age-linked changes in the immune system can influence the composition and functionality of tumor-infiltrating immune cells (TIICs) that play a crucial role in the cancer response. Older patients may have lower levels of TIICs infiltration due to age-related immune senescence particularly T cell function, which can limit the effectivity of cancer immunotherapies. Furthermore, age-related immune dysregulation increases the exhaustion of immune cells, characterized by the dysregulation of ICI-related biomarkers and a dampened response to ICI. Our review aims to provide a comprehensive understanding of the mechanisms that contribute to the impact of age on ICI-related biomarkers and ICI response. Understanding these mechanisms will facilitate the development of treatment approaches tailored to elderly individuals with cancer.


Assuntos
Pesquisa Biomédica , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias , Idoso , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Envelhecimento , Neoplasias/tratamento farmacológico
9.
ACS Appl Mater Interfaces ; 15(19): 23447-23456, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37134190

RESUMO

N-type Mg3Sb2 is attracting increasing focus for its outstanding room-temperature (RT) thermoelectric (TE) performance; however, achieving reliable n-type conduction remains challenging due to negatively charged Mg vacancies. Doping with compensation charges is generally used but does not fundamentally resolve the high intrinsic activity and easy formation of Mg vacancies. Herein, a robust structural and thermoelectric performance is obtained by manipulating Mg intrinsic migration activity by precisely incorporating Ni at the interstitial site. Density functional theory (DFT) indicates that a strong performance originates from a significant thermodynamic preference for Ni occupying the interstitial site across the complete Mg-poor to -rich window, which dramatically promotes the Mg migration barrier and kinetically immobilizes Mg. As a result, the detrimental vacancy-associated ionized scattering is eliminated with a leading room-temperature ZT up to 0.85. This work reveals that interstitial occupation in Mg3Sb2-based materials is a novel approach promoting both structural and thermoelectric performance.

10.
Circulation ; 124(25): 2933-43, 2011 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22104546

RESUMO

BACKGROUND: The interplay between the immune system and abnormal metabolic conditions sustains and propagates a vicious feedback cycle of chronic inflammation and metabolic dysfunction that is critical for atherosclerotic progression. It is well established that abnormal metabolic conditions, such as dyslipidemia and hyperglycemia, cause various cellular stress responses that induce tissue inflammation and immune cell activation, which in turn exacerbate the metabolic dysfunction. However, molecular events linking these processes are not well understood. METHODS AND RESULTS: Tissues and organs of humans and mice with hyperglycemia and hyperlipidemia were examined for expression of ligands for NKG2D, a potent immune-activating receptor expressed by several types of immune cells, and the role of NKG2D in atherosclerosis and metabolic diseases was probed with the use of mice lacking NKG2D or by blocking NKG2D with monoclonal antibodies. NKG2D ligands were upregulated in multiple organs, particularly atherosclerotic aortas and inflamed livers. Ligand upregulation was induced in vitro by abnormal metabolites associated with metabolic dysfunctions. Using apolipoprotein E-deficient mouse models, we demonstrated that preventing NKG2D functions resulted in a dramatic reduction in plaque formation, suppressed systemic and organ inflammation mediated by multiple immune cell types, and alleviated abnormal metabolic conditions. CONCLUSIONS: The NKG2D/ligand interaction is a critical molecular link in the vicious cycle of chronic inflammation and metabolic dysfunction that promotes atherosclerosis and might be a useful target for therapeutic intervention in the disease.


Assuntos
Aterosclerose/imunologia , Diabetes Mellitus Experimental/imunologia , Síndrome Metabólica/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Animais , Anticorpos Bloqueadores/farmacologia , Anticorpos Monoclonais/farmacologia , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/metabolismo , Biomarcadores/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Experimental/metabolismo , Hepatite/imunologia , Hepatite/metabolismo , Humanos , Sistema Imunitário/imunologia , Ligantes , Masculino , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Regulação para Cima/imunologia
11.
J Exp Med ; 203(1): 203-13, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16418393

RESUMO

Nod1 is a member of family of intracellular proteins that mediate host recognition of bacterial peptidoglycan. To characterize immune responses mediated by Nod1, synthetic ligand compounds possessing enhanced ability to stimulate Nod1 were developed to study the function of Nod1. Stimulation of epithelial cells with Nod1 stimulatory molecules induced chemokines and other proinflammatory molecules that are important for innate immune responses and recruitment of acute inflammatory cells. Administration of Nod1 ligands into mice induced chemokines and recruitment of acute inflammatory cells, an activity that was abolished in Nod1-null mice. Microarray analysis revealed that Nod1 stimulation induces a restricted number of genes in intestinal epithelial cells compared with that induced by tumor necrosis factor (TNF) alpha. Nod1 stimulation did not induce TNFalpha, interleukin 12, and interferon gamma, suggesting that the primary role of Nod1 is to induce the recruitment of immune cells. These results indicate that Nod1 functions as a pathogen recognition molecule to induce expression of molecules involved in the early stages of the innate immune response.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Citocinas/imunologia , Neutrófilos/imunologia , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Bactérias/imunologia , Linhagem Celular , Dipeptídeos/imunologia , Células Epiteliais/imunologia , Humanos , Mucosa Intestinal/imunologia , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Adaptadora de Sinalização NOD1 , Análise de Sequência com Séries de Oligonucleotídeos
12.
Mol Ther Nucleic Acids ; 27: 983-997, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35317280

RESUMO

Exosomes are extracellular vesicles released by various cell types that perform various biological functions, mainly mediating communication between different cells, especially those active in cancer. Noncoding RNAs (ncRNAs), of which there are many types, were recently identified as enriched and stable in the exocrine region and play various roles in the occurrence and progression of cancer. Abnormal angiogenesis has been confirmed to be related to human cancer. An increasing number of studies have shown that exosome-derived ncRNAs play an important role in tumor angiogenesis. In this review, we briefly outline the characteristics of exosomes, ncRNAs, and tumor angiogenesis. Then, the mechanism of the impact of exosome-derived ncRNAs on tumor angiogenesis is analyzed from various angles. In addition, we focus on the regulatory role of exosome-derived ncRNAs in angiogenesis in different types of cancer. Furthermore, we emphasize the potential role of exosome-derived ncRNAs as biomarkers in cancer diagnosis and prognosis and therapeutic targets in the treatment of tumors.

13.
Brain Res Bull ; 173: 116-123, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33991608

RESUMO

Sialylation, one of the most common and complex modes of glycosylation, corresponds with the development of the infant brain and nervous system. The most prevalent neurodegenerative disease is Alzheimer's disease (AD), which is mainly characterized by cognitive decline and behavioral disorders. However, the relationship between sialylation and AD occurrence is poorly understood. In this article, we reviewed the role of sialylation on the occurrence and development of AD, then discussed the value of sialylation modification for AD diagnosis and treatment.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Glicosilação , Humanos
14.
Materials (Basel) ; 14(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204313

RESUMO

Perfobond rib (PBL) shear connectors, made up of the perforated steel plates with the penetrating rebars passing through the holes, are extensively adopted in steel-concrete composite structures for their excellent performance. The adequate understanding of mechanical properties for PBL connectors is of great significance for their reasonable design. In this study, a push out experiment, including 12 specimens with the parameters of concrete strength, diameter of penetrating rebars and the number of holes on perforated steel plate, was performed to explore the mechanical behavior of PBL connectors with steel fiber high strength concrete (SFHSC). The experimental results showed that the shear capacity of the PBL connectors increased with the increase in concrete strength, diameter of the penetrating rebars and the number of holes. Furthermore, a general prediction formula for the shear capacity of PBL connectors was developed, which considers the shear contribution of concrete dowels, concrete end-bearing, interfacial bonding between the perforated steel plates and concrete and the penetrating rebars as well as the enhancement effect of steel fibers. The prediction results of the equation are in good agreement with the experimental data and could provide a reference for the design of PBL connectors.

15.
Front Immunol ; 12: 639636, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33767709

RESUMO

Renal cell carcinoma is a highly heterogeneous cancer group, and the complex microenvironment of the tumor provides appropriate immune evasion opportunities. The molecular mechanism of immune escape in renal cell carcinoma is currently a hot issue, focusing primarily on the major complex of histocompatibility, immunosuppressive cells, their secreted immunosuppressive cytokines, and apoptosis molecule signal transduction. Immunotherapy is the best treatment option for patients with metastatic or advanced renal cell carcinoma and combination immunotherapy based on a variety of principles has shown promising prospects. Comprehensive and in-depth knowledge of the molecular mechanism of immune escape in renal cell carcinoma is of vital importance for the clinical implementation of effective therapies. The goal of this review is to address research into the mechanisms of immune escape in renal cell carcinoma and the use of the latest immunotherapy. In addition, we are all looking forward to the latest frontiers of experimental combination immunotherapy.


Assuntos
Carcinoma de Células Renais/imunologia , Imunoterapia/métodos , Neoplasias Renais/imunologia , Evasão Tumoral/imunologia , Animais , Carcinoma de Células Renais/terapia , Humanos , Neoplasias Renais/terapia
16.
Sci Rep ; 9(1): 17788, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780690

RESUMO

This paper aims to eliminate the disharmony between simulation and experiment, and takes the mechanical properties of 6082-T6 Al alloy as an example. In order to obtain the equivalent distribution of material properties after considering the randomicity of materials, a new inversion method combining with stochastic finite element method (SFEM) is proposed. Besides, the discrete random field in SFEM is established by an innovative method to overcome some discretization difficulties in conventional methods. In summary, the generic methods proposed in this study can give a new solution for the correlation of meso-structure and macro-performance in computational materials science.

17.
Zhonghua Er Ke Za Zhi ; 54(2): 137-40, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-26875465

RESUMO

OBJECTIVE: To investigate the etiology and clinical manifestation of hemoptysis in children. METHOD: A retrospective analysis was performed for 106 cases of hemoptysis who were admitted to The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University from January 2005 to December 2014.The clinical information including laboratory tests and image data were collected and analyzed. RESULT: A total of 106 patients (50 males and 56 females) were identified. The median age was 9.1 years (range 2 months to 18 years). Pneumonia (35, 31.1%) was the most common etiology of hemoptysis, which included bacterial pneumonia (27 cases), mycoplasmal pneumonia(4 cases), chlamydial pneumonia (3 cases), and influenza pneumonia(1 case). Other causes included bronchitis(15, 14.2%), pulmonary tuberculosis (11, 10.4%), bronchiectasis (11, 10.4%), diffuse alveolar hemorrhage (8, 7.5%), idiopathic pulmonary hemosiderosis(6, 5.7%), cardiovascular dysplasia(6, 5.7%), pulmonary contusion (4, 3.8%), foreign body in bronchus (2, 1.9%), allergic bronchopulmonary aspergillosis (2, 1.9%). Eighty-six patients manifested mild hemoptysis; moderate and massive hemoptysis were found in nine and eleven patients, respectively. Pneumonia accounted for 33.7% of mild hemoptysis and 45.5% of massive hemoptysis were due to bronchiectasis; 80.2% were treated with antibiotics and 41.5% were given hemostatic agents; 8.5% received lobectomy. Ninety-six patients (90.6%) were cured and parents gave up treatment in 4 cases (3.8%). Six patients (5.7%) suffered from recurrent hemoptysis. CONCLUSION: Hemoptysis mainly occurred in children who were older than 6 years, the most common cause of hemoptysis was respiratory tract infection. In most cases, the amount of hemoptysis was small and the overall prognosis was good.


Assuntos
Hemoptise/diagnóstico , Hemoptise/etiologia , Hemoptise/terapia , Adolescente , Bronquiectasia/complicações , Bronquite/complicações , Criança , Pré-Escolar , Feminino , Corpos Estranhos/complicações , Hemossiderose/complicações , Humanos , Lactente , Influenza Humana/complicações , Pneumopatias/complicações , Lesão Pulmonar/complicações , Masculino , Pneumonia Bacteriana/complicações , Prognóstico , Estudos Retrospectivos , Tuberculose Pulmonar/complicações , Hemossiderose Pulmonar
18.
Sci Rep ; 5: 15186, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26471355

RESUMO

Ultrafine ruthenium nanoparticles (NPs) within the mesopores of the SBA-15 have been successfully prepared by using a "double solvents" method, in which n-hexane is used as a hydrophobic solvent and RuCl3 aqueous solution is used as a hydrophilic solvent. After the impregnation and reduction processes, the samples were characterized by XRD, TEM, EDX, XPS, N2 adsorption-desorption, and ICP techniques. The TEM images show that small sized Ru NPs with an average size of 3.0 ± 0.8 nm are uniformly dispersed in the mesopores of SBA-15. The as-synthesized Ru@SBA-15 nanocomposites (NCs) display exceptional catalytic activity for hydrogen generation by the hydrolysis of ammonia borane (NH3BH3, AB) and hydrazine borane (N2H4BH3, HB) at room temperature with the turnover frequency (TOF) value of 316 and 706 mol H2 (mol Ru min)(-1), respectively, relatively high values reported so far for the same reaction. The activation energies (Ea) for the hydrolysis of AB and HB catalyzed by Ru@SBA-15 NCs are measured to be 34.8 ± 2 and 41.3 ± 2 kJ mol(-1), respectively. Moreover, Ru@SBA-15 NCs also show satisfied durable stability for the hydrolytic dehydrogenation of AB and HB, respectively.

19.
J Biol Chem ; 282(16): 11757-64, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17322292

RESUMO

Nod1 is an intracellular protein that is involved in recognition of bacterial molecules and whose genetic variation has been linked to several inflammatory diseases. Previous studies suggested that the recognition core of Nod1 stimulatory molecules is gamma-D-glutamyl-meso-diaminopimelic acid (iE-DAP), but the identity of the major Nod1 stimulatory molecule produced by bacteria remains unknown. Here we show that bacteria produce lipophilic molecules capable of stimulating Nod1. Analysis of synthetic compounds revealed stereoselectivity of the DAP residue and that conjugation of lipophilic acyl residues specifically enhances the Nod1 stimulatory activity of the core iE-DAP. Furthermore, we demonstrate that lipophilic molecules induce and/or enhance the secretion of innate immune mediators from primary mouse mesothelial cells and human monocytic MonoMac6 cells, and this effect is mediated through Nod1. These results provide insight into the mechanism of immune recognition via Nod1, which might be useful in the design and testing of novel immunoregulators.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Ácido Diaminopimélico/análogos & derivados , Ácido Diaminopimélico/química , Sistema Imunitário , Proteína Adaptadora de Sinalização NOD1/fisiologia , Peptidoglicano/química , Animais , Proteínas de Bactérias/metabolismo , Linhagem Celular , Ácido Diaminopimélico/farmacologia , Escherichia coli/metabolismo , Humanos , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Químicos , Estereoisomerismo
20.
J Biol Chem ; 281(39): 29054-63, 2006 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-16870615

RESUMO

Nod1 and Nod2 are intracellular proteins that are involved in recognition of bacterial molecules and their genetic variations have been linked to several inflammatory diseases that are strongly affected by environmental factors. However, the distribution of Nod1- and Nod2-stimulatory molecules in different bacterial species and environments is unknown. Here we established a quantitative bioassay to screen and characterize Nod1- and Nod2-stimulatory activities in different environmental sites and bacterial species. Using this system, we found that common environments including foods and soils contain high levels of Nod1- and Nod2-stimulatory activities. Several Bacillus species were identified to possess the highest Nod1-stimulatory activity among soil bacteria. Unlike other immunostimulatory molecules, the higher level of Nod1-stimulatory activity was found in the culture supernatant and not in extracts from whole cell bacteria. Nod1-stimulatory molecules were highly stable at extreme pH and boiling conditions and were synthesized in an amidase- and sltY-independent manner. These results suggest a novel mechanism by which bacteria present in the environment stimulate the host immune system through Nod1.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Bacillus/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteína Adaptadora de Sinalização NOD1/fisiologia , Proteína Adaptadora de Sinalização NOD2/fisiologia , Animais , Meios de Cultura/metabolismo , Escherichia coli/metabolismo , Humanos , Inflamação , Ligantes , Camundongos , NF-kappa B/metabolismo , Plasmídeos/metabolismo
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