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1.
Nature ; 627(8005): 783-788, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38538937

RESUMO

Controlling the intensity of emitted light and charge current is the basis of transferring and processing information1. By contrast, robust information storage and magnetic random-access memories are implemented using the spin of the carrier and the associated magnetization in ferromagnets2. The missing link between the respective disciplines of photonics, electronics and spintronics is to modulate the circular polarization of the emitted light, rather than its intensity, by electrically controlled magnetization. Here we demonstrate that this missing link is established at room temperature and zero applied magnetic field in light-emitting diodes2-7, through the transfer of angular momentum between photons, electrons and ferromagnets. With spin-orbit torque8-11, a charge current generates also a spin current to electrically switch the magnetization. This switching determines the spin orientation of injected carriers into semiconductors, in which the transfer of angular momentum from the electron spin to photon controls the circular polarization of the emitted light2. The spin-photon conversion with the nonvolatile control of magnetization opens paths to seamlessly integrate information transfer, processing and storage. Our results provide substantial advances towards electrically controlled ultrafast modulation of circular polarization and spin injection with magnetization dynamics for the next-generation information and communication technology12, including space-light data transfer. The same operating principle in scaled-down structures or using two-dimensional materials will enable transformative opportunities for quantum information processing with spin-controlled single-photon sources, as well as for implementing spin-dependent time-resolved spectroscopies.

3.
Pediatr Res ; 93(6): 1765-1771, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36151297

RESUMO

BACKGROUND: Numerous cellular components have been well demonstrated in human breast milk. However, little is known about their dynamic change, influencing factors, and potential clinical impacts on infants. METHODS: Sixty and forty-five healthy mother-infant pairs were enrolled in the colostrum group and mature milk group, respectively. Participants' demographic and clinical information were collected by questionnaires, and the infants were followed up until 6 months after birth through telephone interview. Colostrum and mature milk were collected, and the percentage of various cell components were determined by flow cytometric analysis. RESULTS: The results showed that, the total cell numbers, and the percentages of some stem cells, including CD34+, CD117+, CD133+, CD90+, CD105+, and CD146+ cells, were different in colostrum and mature milk. Besides, participants' characteristics had influence on the cellular components. Finally, high-CD34+ cells in colostrum, as well as the high-CD133+ cells and low-CD105+ cells in mature milk were associated with a significantly increased risk of infantile eczema within their first 3 months after birth. CONCLUSIONS: Our data showed a dynamic change of cellular components, identified some of their influencing factors and their potential clinical impacts on infantile eczema, which helps to better understand the cellular components in human breast milk. IMPACT: Some stem cell markers were dynamically changed in human colostrum and mature milk. Different cellular components were shown to be influenced by different participants' characteristics. High percentage of CD34+ cells in colostrum, as well as high percentage of CD133+ cells and low percentage of CD105+ cells in mature milk, were associated with a significantly increased risk of infantile eczema within their first 3 months after birth. To our knowledge, this is the first study on the clinical impacts of stem cells on infantile diseases, which helps to give a better understanding of human breast milk.


Assuntos
Dermatite Atópica , Leite Humano , Lactente , Feminino , Gravidez , Humanos , Colostro , Mães , Parto
4.
Clin Immunol ; 229: 108800, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34289424

RESUMO

The study aimed to investigate the soluble programmed death-1 (sPD-1) and its ligand (sPD-L1) levels in systemic juvenile idiopathic arthritis (sJIA) patients and elucidate its underlying immunomodulatory mechanisms. Plasma levels of sPD-1, sPD-L1 and related cytokines and proteins were detected using an enzyme-linked immunosorbent assay (ELISA) and Luminex. The effects of PD-1/PD-L1 signal on mDC (myeloid dendritic cell) and IL-6 secretion were measured using flow cytometry. The results revealed decreased levels of sPD-1 in sJIA patients negatively correlated with JADAS-27, PGA, PtGA and CRP. sJIA patients had lower CD86 and MHC-II expression on mDC. When blocking PD-1/PD-L1 signal, IL-6 secretion of DC were increased. Our finding displayed downregulated sPD-1 was related with clinical indicators and could be a new biomarker for sJIA diagnosis. The reduced membrane and soluble forms of PD-1/PD-L1 might take part in sJIA pathogenesis by enhancing mDC proliferation and IL-6 secretion.


Assuntos
Artrite Juvenil/imunologia , Antígeno B7-H1/imunologia , Receptor de Morte Celular Programada 1/imunologia , Artrite Juvenil/sangue , Artrite Juvenil/diagnóstico , Antígeno B7-H1/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Citocinas/sangue , Células Dendríticas/imunologia , Regulação para Baixo , Feminino , Humanos , Interleucina-6/sangue , Masculino , Receptor de Morte Celular Programada 1/sangue , Transdução de Sinais/imunologia , Solubilidade
5.
Nano Lett ; 19(3): 1788-1795, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30741548

RESUMO

Two dimensional (2D) materials have found various applications because of their unique physical properties. For example, graphene has been used as the electron transparent membrane for liquid cell transmission electron microscopy (TEM) due to its high mechanical strength and flexibility, single-atom thickness, chemical inertness, etc. Here, we report using 2D MoS2 as a functional substrate as well as the membrane window for liquid cell TEM, which is enabled by our facile and polymer-free MoS2 transfer process. This provides the opportunity to investigate the growth of Pt nanocrystals on MoS2 substrates, which elucidates the formation mechanisms of such heterostructured 2D materials. We find that Pt nanocrystals formed in MoS2 liquid cells have a strong tendency to align their crystal lattice with that of MoS2, suggesting a van der Waals epitaxial relationship. Importantly, we can study its impact on the kinetics of the nanocrystal formation. The development of MoS2 liquid cells will allow further study of various liquid phenomena on MoS2, and the polymer-free MoS2 transfer process will be implemented in a wide range of applications.

7.
Curr Allergy Asthma Rep ; 18(10): 51, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30112673

RESUMO

PURPOSE OF REVIEW: The hyper IgE syndromes (HIES) comprise a group of rare primary immunodeficiency disorders (PIDDs), which are characterized by extremely high serum IgE levels, eczema, recurrent skin and pulmonary infections. Both autosomal dominant (AD) HIES due to STAT3 mutations and autosomal recessive (AR) HIES due to PGM3, SPINK5, DOCK8 and TKY2 mutations have been reported. Here, we aim to summarize and compare the major clinical manifestations of different subtypes of HIES. We will also discuss otitis media, which usually do not get enough attention in HIES. Update and familiarity with these clinical features will help to make a better diagnose, assessment and treatment of HIES. RECENT FINDINGS: Although hyper serum IgE levels have been identified in PGM3 deficiency and Comel-Netherton syndrome, PGM3 and SPINK5 genes were not included in the list of genetic etiologies of AR-HIES by the Expert Committee of the International Union of Immunological Societies until 2015. The identification of these HIES-causing genes greatly promoted the pathogenic mechanism studies of HIES. Also, in recent years, more clinical manifestations, which were often not of concern in HIES patients, have been shown to be highly related to HIES. For example, a significantly high frequency of vascular and gastrointestinal abnormities has been reported in STAT3-deficient AD-HIES patients. These new findings might help to provide new clues to the functional study of these HIES-related genes. This review summarizes and compares the major clinical manifestations of different subtypes of HIES, and we suggest that the incidence and severity of otitis media should not be underestimated in HIES patients.


Assuntos
Síndrome de Job , Gastroenteropatias/complicações , Gastroenteropatias/etiologia , Humanos , Síndrome de Job/complicações , Síndrome de Job/diagnóstico , Síndrome de Job/genética , Mutação , Otite Média/complicações , Infecções Respiratórias/complicações , Dermatopatias/complicações
8.
Pediatr Nephrol ; 33(5): 837-845, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29264699

RESUMO

BACKGROUND: Traditional serological biomarkers often fail to assess systemic lupus erythematosus (SLE) disease activity and discriminate lupus nephritis (LN). The aim of this study was to identify novel markers for evaluating renal and overall disease activity in Chinese patients with pediatric systemic lupus erythematosus (pSLE). METHODS: The study included 46 patients with pSLE (35 girls, 11 boys; average age 13.3 ± 2.6 years) and 31 matched healthy controls (22 girls, 9 boys; average age 12.3 ± 2.4 years). The SLE Disease Activity Index (SLEDAI) and renal SLEDAI were used to assess disease activity. Nine different soluble mediators in plasma, including tumor necrosis factor alpha (TNF-α), platelet-derived growth factor-BB (PDGF-BB), interferon (IFN) gamma inducible protein 10 (IP-10), interleukin (IL)-1ß, IFN-γ, IL-17A, IL-2, Fas and Fas ligand, were measured by Luminex assay and compared between patients with active and inactive pSLE as well as between patients with pSLE with active and inactive renal disease. Receiver operating characteristic curve analysis was used to measure the discrimination accuracy. RESULTS: Of the 46 patients with pSLE, 30 (65.2%) had LN. These patients had significantly elevated levels of serum TNF-α, PDGF-BB, IP-10 and Fas. The serum levels of IP-10 were also significantly higher in patients with active pSLE. We found that IP-10 was also more sensitive and specific than conventional laboratory parameters, including anti-double-stranded DNA and complement components C3 and C4, for distinguishing active lupus from quiescent lupus. The serum level of IP-10 was also significantly increased in children with pSLE with active renal disease relative to those with inactive renal disease. There was also a positive correlation between serum IP-10 levels and renal SLEDAI scores as well as with 24 h urine protein. CONCLUSIONS: Serum IP-10 is useful for identifying renal and overall disease activity in children with pSLE.


Assuntos
Biomarcadores/sangue , Quimiocina CXCL10/sangue , Nefrite Lúpica/sangue , Adolescente , Povo Asiático , Estudos de Casos e Controles , Criança , Progressão da Doença , Feminino , Humanos , Rim/patologia , Nefrite Lúpica/diagnóstico , Masculino , Curva ROC , Índice de Gravidade de Doença
9.
J Clin Immunol ; 37(2): 166-179, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28197791

RESUMO

PURPOSE: Autosomal dominant hyper-IgE syndrome (AD-HIES) is a rare complicated primary immunodeficiency disease (PID). Signal transducer and activator of transcription 3 (STAT3) gene mutation is found to cause AD-HIES. The distribution of AD-HIES patients with STAT3 deficiency in the Chinese population is not clear. Herein, we retrospectively report 17 AD-HIES patients with STAT3 deficiency and demonstrate their clinical, immunological, and genetic features. METHODS: Patients' clinical data were collected from their medical records. Routine laboratory testing results included lymphocyte subset analysis and immunoglobulin quantification. STAT3 mutations were investigated by sequencing of genomic DNA. RESULTS: Among 575 patients with PID, 28 (4.87%) were clinically diagnosed as HIES. Among them, 17 (2.96%) were confirmed as STAT3 mutant AD-HIES. The ratio of male to female patients was 8:9. All of the 17 patients had NIH scores over 40 points. The mean ages at onset and diagnosis were 1.05 and 10.35 years, respectively. Three patients (17.65%, 3/17) died with a mean age of 13.33 years. Eczema, recurrent skin infection, and respiratory tract infection were the most common clinical symptoms and are present in all of the 17 patients in this study. Six patients (37.5%, 6/16) suffered complication from BCG vaccination. Noninfection symptoms are characteristic facial features in 17 patients (100%, 17/17), retention of primary teeth in 10 patients (90.91%, 10/11), and abnormal bone fractures in 7 patients (41.18%, 7/17). Eleven types of STAT3 mutations were identified in 17 patients, including 1 novel mutation. CONCLUSIONS: We here retrospectively report the largest Chinese cohort of AD-HIES patients with STAT3 mutation. Unique features, when compared to existing literature reports, include (1) later age of diagnosis, (2) significantly higher rate of BCG complications, and (3) lower rate of candidiasis and chronic otitis media.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Síndrome de Job/diagnóstico , Síndrome de Job/genética , Fenótipo , Adolescente , Adulto , Criança , Pré-Escolar , China , Eosinófilos , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunofenotipagem , Síndrome de Job/complicações , Síndrome de Job/imunologia , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Mutação , Fator de Transcrição STAT3/genética , Avaliação de Sintomas , Adulto Jovem
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(9): 912-7, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26412169

RESUMO

OBJECTIVE: To investigate the major allergens in children with different allergic diseases, and to provide theoretical evidence for the clinical prevention, diagnosis, and treatment of allergic diseases in children. METHODS: Skin prick test (SPT) was conducted to detect allergens in 1179 allergic children. According to clinical diagnoses, patients were categorized into six groups: atopic dermatitis (n=140), allergic gastroenteritis (n=37), allergic conjunctivitis (n=77), asthma (n=285), allergic rhinitis (n=301) and allergic co-morbidity (n=329) groups. RESULTS: Of the 1179 patients, 82.0% had positive SPT results; the most prevalent inhalant allergens were Dermatophagoides farinae (68.1%) and Dermatophagoides pteronyssinus (53.5%), while the most common food allergens were milk (5.0%) and eggs (4.8%). The proportions were 84.3% and 83.8% for patients under or equal to 3 years of age in the atopic dermatitis and allergic gastroenteritis groups, respectively. Patients over 4 years of age accounted for the majority of the other four groups. Food as major allergens were found in both atopic dermatitis and allergic gastroenteritis groups; eggs and Dermatophagoides farinae were the most common allergens for the former group, while eggs and milk for the latter group. Inhalant allergens were the major allergens in the allergic conjunctivitis, allergic rhinitis, asthma, and allergic co-morbidity groups, and the most prevalent allergens were Dermatophagoides farinae and Dermatophagoides pteronyssinus. CONCLUSIONS: There are differences in the distribution of age and allergen types in children with different allergic diseases. Atopic dermatitis and allergic gastroenteritis are prevalent in infants and young children, and food allergens are more common. Patients in allergic conjunctivitis, allergic rhinitis, asthma, and allergic co-morbidity groups are mostly children over 4 years of age, and inhalant allergens are more common.


Assuntos
Alérgenos/imunologia , Hipersensibilidade/etiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Testes Cutâneos
11.
Br J Nutr ; 111(5): 867-74, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24124699

RESUMO

Human milk provides infants with various immune molecules. The objective of the present study was to measure human ß-defensin-1 (hBD-1) and human ß-defensin-2 (hBD-2) levels in the colostrum and mature milk of healthy Han Chinese, to identify factors regulating milk hBD-1 and hBD-2 expression and to explore the potential protective effect of milk hBD-1 and hBD-2 on infants. A total of 100 mothers and their babies were recruited into the study. Sociodemographic characteristics and other factors were obtained by a questionnaire. Babies were followed up for a period of 6 months. Colostrum samples (n 100) and mature milk samples (n 82) were collected by hand expression. The hBD-1 and hBD-2 concentrations were measured by ELISA. The hBD-1 and hBD-2 levels differed in the colostrum and mature milk. In the colostrum, the concentration ranges of hBD-1 and hBD-2 were 1·04-12·81 µg/ml and 0·31-19·12 ng/ml, respectively. In mature milk, the hBD-1 and hBD-2 levels were 1·03-31·76 ng/ml and 52·65-182·29 pg/ml, respectively. Several independent factors influence their production. The multivariable analysis showed a strong association between pre-pregnancy BMI and hBD-1 levels in the colostrum (P=0·001), mode of delivery was significantly associated with hBD-2 levels in the colostrum (P=0·006) and gestational age was significantly associated with hBD-1 levels in mature milk (P= 0·010). During the first 6 months of life, the incidence rate of upper respiratory infection was found to be less in the high-colostrum hBD-1 group than in the low-colostrum hBD-1 group (χ²=4·995, P=0·025). The present study suggested that the abundance of hBD-1 in the colostrum may have a protective function against upper respiratory infection for infants younger than 6 months.


Assuntos
Colostro/química , Lactação/metabolismo , Leite Humano/química , beta-Defensinas/análise , Povo Asiático , Índice de Massa Corporal , Cesárea/efeitos adversos , Desenvolvimento Infantil , China/epidemiologia , Colostro/citologia , Colostro/metabolismo , Feminino , Seguimentos , Regulação da Expressão Gênica , Humanos , Incidência , Recém-Nascido , Masculino , Leite Humano/citologia , Leite Humano/metabolismo , Gravidez , Nascimento Prematuro/metabolismo , Nascimento Prematuro/fisiopatologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Infecções Respiratórias/prevenção & controle , beta-Defensinas/genética , beta-Defensinas/metabolismo
12.
Immunopharmacol Immunotoxicol ; 36(1): 33-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24308297

RESUMO

CONTEXT: Intravenous immunoglobulin (IVIG) has been successfully applied in immune-related diseases of adults and neonates, such as human immunodeficiency virus (HIV) infection and systemic lupus erythematosus (SLE). OBJECTIVE: This study aims to investigate the distinct impacts of IVIG on cultured dendritic cells (DCs) from newborn and healthy adult. MATERIALS AND METHODS: Blood samples were collected from eight full-term newborns and eight healthy adult volunteers. DCs from cord blood and peripheral blood were both cultured in the RPMI 1640 medium containing 10% fetal calf serum, 50 ng/ml granulocyte/macrophage colony-stimulating factor (GM-CSF) and 10 ng/ml recombinant human interleukin-4 (rhIL-4) for 5 d with therapeutic IVIG (20 mg/ml) or physiological IVIG (10 mg/ml). Lipopolysaccharides (LPSs, 1 µg/ml) were added on the fifth day to induce the maturation of immature DCs. The phagocytosis of monocytes, expression of MR (mannose receptor), CD14, CD1a, CD80, CD83, CD86 and MHC II were examined by flow cytometry. The expression of IL-4 mRNA was detected by RT-PCR, while IFN-γ, IL-12 and IL-10 were analyzed by enzyme-linked immunosorbent assay (ELISA) commercial kits. RESULTS: IVIG of therapeutic dose inhibited the phagocytosis, differentiation and maturation of DCs, whereas physiological dose exhibited an accelerated role in vitro, especially on DCs from neonates, but aroused different effects on cytokine secretion. DISCUSSION AND CONCLUSION: The different responses are generally due to immature immune system of neonate, which has a limit capacity to maintain immunity homeostasis. Modulation of DCs phagocytosis, differentiation, maturation and cytokine secretion by IVIG is of potential relevance to its dosage and immune status of patients.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Citocinas/imunologia , Células Dendríticas/imunologia , Imunoglobulinas Intravenosas/farmacologia , Fatores Imunológicos/farmacologia , Fagocitose/efeitos dos fármacos , Adulto , Diferenciação Celular/imunologia , Células Dendríticas/patologia , Relação Dose-Resposta a Droga , Relação Dose-Resposta Imunológica , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos , Recém-Nascido , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Fagocitose/imunologia
13.
Cell Discov ; 10(1): 53, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38763950

RESUMO

Peripheral CD8+ T cell number is tightly controlled but the precise molecular mechanism regulating this process is still not fully understood. In this study, we found that epilepsy patients with loss of function mutation of DEPDC5 had reduced peripheral CD8+ T cells, and DEPDC5 expression positively correlated with tumor-infiltrating CD8+ T cells as well as overall cancer patient survival, indicating that DEPDC5 may control peripheral CD8+ T cell homeostasis. Significantly, mice with T cell-specific Depdc5 deletion also had reduced peripheral CD8+ T cells and impaired anti-tumor immunity. Mechanistically, Depdc5-deficient CD8+ T cells produced high levels of xanthine oxidase and lipid ROS due to hyper-mTORC1-induced expression of ATF4, leading to spontaneous ferroptosis. Together, our study links DEPDC5-mediated mTORC1 signaling with CD8+ T cell protection from ferroptosis, thereby revealing a novel strategy for enhancing anti-tumor immunity via suppression of ferroptosis.

14.
Adv Mater ; : e2401611, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848668

RESUMO

Integrating tunneling magnetoresistance (TMR) effect in memristors is a long-term aspiration because it allows to realize multifunctional devices, such as multi-state memory and tunable plasticity for synaptic function. However, the reported TMR in different multiferroic tunnel junctions is limited to 100%. This work demonstrates a giant TMR of -266% in La0.6Sr0.4MnO3(LSMO)/poly(vinylidene fluoride)(PVDF)/Co memristor with thin organic barrier. Different from the ferroelectricity-based memristors, this work discovers that the voltage-driven florine (F) motion in the junction generates a huge reversible resistivity change up to 106% with nanosecond (ns) timescale. Removing F from PVDF layer suppresses the dipole field in the tunneling barrier, thereby significantly enhances the TMR. Furthermore, the TMR can be tuned by different polarizing voltage due to the strong modification of spin-polarization at the LSMO/PVDF interface upon F doping. Combining of high TMR in the organic memristor paves the way to develop high-performance multifunctional devices for storage and neuromorphic applications.

15.
J Clin Immunol ; 33(3): 526-39, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23250629

RESUMO

Severe combined immunodeficiency (SCID), a rare type of genetic associated immune disorder, is poorly characterized in mainland China. We retrospectively reviewed 44 patients with SCID who received treatment from 2004 to 2011 in Shanghai, China, and herein summarize their clinical manifestations and immunological and preliminary genetic features. The male-to-female ratio was 10:1. Twenty five patients presented with X-SCID symptoms. Only one patient was diagnosed before the onset of symptoms due to positive family history. The mean time of delay in the diagnosis of X-SCID was 2.69 months (range, 0.5-8.67). Thirty-seven of the 44 patients died by the end of 2011 with the mean age of death being 7.87 months (range, 1.33-31). Six patients received hematopoietic stem cell transplantation (HSCT); only one of them survived, who was transplanted twice. The time between onset and death was shorter in the HSCT-treated group compared with the untreated group (2.87 ± 1.28 and 3.34 ± 0.59 months, respectively), probably due to active infections during transplantation. Bacillus Calmette-Guérin (BCG) complications occurred in 14 of the 34 patients who received BCG vaccination. Transfusion-induced graft-versus-host disease occurred in 5 patients. Total 20 mutations in interleukin-2 receptor subunit gamma (IL2RG) were identified in 22 patients, including 11 novel mutations. Most patients were misdiagnosed before referred to our SCID Center. Therefore, establishing more diagnostic centers dedicated to the care of PID and accessible by primary immunodeficiency patients will facilitate early, correct diagnosis and better care of SCID in China.


Assuntos
Subunidade gama Comum de Receptores de Interleucina/genética , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/genética , Adolescente , Adulto , Idade de Início , Vacina BCG/imunologia , Criança , Pré-Escolar , China , Feminino , Genótipo , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Recém-Nascido , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Mutação , Imunodeficiência Combinada Severa/terapia , Adulto Jovem
16.
PLoS One ; 18(1): e0277913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662785

RESUMO

Exploration of dynamic human activity gives significant insights into understanding the urban environment and can help to reinforce scientific urban management strategies. Lots of studies are arising regarding the significant human activity changes in global metropolises and regions affected by COVID-19 containment policies. However, the variations of human activity dynamics amid different phases divided by the non-pharmaceutical intervention policies (e.g., stay-at-home, lockdown) have not been investigated across urban areas in space and time and discussed with the urban characteristic determinants. In this study, we aim to explore the influence of different restriction phases on dynamic human activity through sensing human activity zones (HAZs) and their dominated urban characteristics. Herein, we proposed an explainable analysis framework to explore the HAZ variations consisting of three parts, i.e., footfall detection, HAZs delineation and the identification of relationships between urban characteristics and HAZs. In our study area of Greater London, United Kingdom, we first utilised the footfall detection method to extract human activity metrics (footfalls) counted by visits/stays at space and time from the anonymous mobile phone GPS trajectories. Then, we characterised HAZs based on the homogeneity of daily human footfalls at census output areas (OAs) during the predefined restriction phases in the UK. Lastly, we examined the feature importance of explanatory variables as the metric of the relationship between human activity and urban characteristics using machine learning classifiers. The results show that dynamic human activity exhibits statistically significant differences in terms of the HAZ distributions across restriction phases and is strongly associated with urban characteristics (e.g., specific land use types) during the COVID-19 pandemic. These findings can improve the understanding of the variation of human activity patterns during the pandemic and offer insights into city management resource allocation in urban areas concerning dynamic human activity.


Assuntos
COVID-19 , Pandemias , Humanos , Londres/epidemiologia , Big Data , Controle de Doenças Transmissíveis , COVID-19/epidemiologia , Atividades Humanas
17.
Transl Pediatr ; 12(6): 1139-1147, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37427064

RESUMO

Background: Human breast milk, which comprises numerous bioactive compositions, has been well-demonstrated to be benefit to the infants in both short-term and long-term outcomes. We aim to determine the concentration of transforming growth factor beta 1 (TGF-ß1) and mucin 1 (MUC1) in human breast milk, identify their influencing factors, and explore their association with infantile diseases. Methods: Ninety paired mother-infants were enrolled in this study, and their demographic and clinical information was collected and analyzed. Paired colostrum and mature milk samples were collected from the healthy mothers within 5 days and at about 42 days after delivery, respectively. The concentrations of TGF-ß1 and MUC1 were determined by enzyme-linked immunosorbent assay. Results: The results showed that the concentrations of TGF-ß1 and MUC1 in human breast milk dynamically changed during lactation, and their concentrations were significantly higher in colostrum than in mature milk. Advanced maternal age was associated with a significantly increased TGF-ß1 concentration in colostrum, and caesarean delivery was significantly associated with an increased MUC1 concentration in colostrum. Finally, a high concentration of TGF-ß1 in colostrum was significantly associated with a higher risk of infantile diarrhea within the first 3 months after giving birth, and infantile upper respiratory infection (URI) within the first 6 months after giving birth. Conclusions: To the best of our knowledge, we for the first time showed that a high concentration of TGF-ß1 in human breast milk was significantly associated with an increased risk of infantile diarrhea and URI, which helps to give a better understanding of the relationship between the TGF-ß1 in human breast milk and infantile diseases.

18.
ACS Appl Mater Interfaces ; 15(32): 38592-38602, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550946

RESUMO

Disordered topological insulator (TI) films have gained intense interest by benefiting from both the TI's exotic transport properties and the advantage of mass production by sputtering. Here, we report on the clear evidence of spin-charge conversion (SCC) in amorphous Gd-alloyed BixSe1-x (BSG)/CoFeB bilayers fabricated by sputtering, which could be related to the amorphous TI surface states. Two methods have been employed to study SCC in BSG (tBSG = 6-16 nm)/CoFeB(5 nm) bilayers with different BSG thicknesses. First, spin pumping is used to generate a spin current in CoFeB and detect SCC by the inverse Edelstein effect (IEE). The maximum SCC efficiency (SCE) is measured to be as large as 0.035 nm (IEE length λIEE) in a 6 nm thick BSG sample, which shows a strong decay when tBSG increases due to the increase of BSG surface roughness. The second method is THz time-domain spectroscopy, which reveals a small tBSG dependence of SCE, validating the occurrence of a pure interface state-related SCC. Furthermore, our angle-resolved photoemission spectroscopy data show dispersive two-dimensional surface states that cross the bulk gap until the Fermi level, strengthening the possibility of SCC due to the amorphous TI states. Our studies provide a new experimental direction toward the search for topological systems in amorphous solids.

19.
Comput Urban Sci ; 2(1): 13, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692614

RESUMO

Crime changes have been reported as a result of human routine activity shifting due to containment policies, such as stay-at-home (SAH) mandates during the COVID-19 pandemic. However, the way in which the manifestation of crime in both space and time is affected by dynamic human activities has not been explored in depth in empirical studies. Here, we aim to quantitatively measure the spatio-temporal stratified associations between crime patterns and human activities in the context of an unstable period of the ever-changing socio-demographic backcloth. We propose an analytical framework to detect the stratified associations between dynamic human activities and crimes in urban areas. In a case study of San Francisco, United States, we first identify human activity zones (HAZs) based on the similarity of daily footfall signatures on census block groups (CBGs). Then, we examine the spatial associations between crime spatial distributions at the CBG-level and the HAZs using spatial stratified heterogeneity statistical measurements. Thirdly, we use different temporal observation scales around the effective date of the SAH mandate during the COVID-19 pandemic to investigate the dynamic nature of the associations. The results reveal that the spatial patterns of most crime types are statistically significantly associated with that of human activities zones. Property crime exhibits a higher stratified association than violent crime across all temporal scales. Further, the strongest association is obtained with the eight-week time span centred around the SAH order. These findings not only enhance our understanding of the relationships between urban crime and human activities, but also offer insights into that tailored crime intervention strategies need to consider human activity variables.

20.
Front Immunol ; 13: 821457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345674

RESUMO

Toll like receptors (TLRs) induced response plays a vital role in B-cell development and activation, in which TLR7-mediated and TLR9-mediated response interact together and play antagonistic or cooperative roles at different situations. Previous studies showed that the transcription factor signal transducer and activator of transcription (STAT) 3 was one of the key transcriptional factors (TFs) needed for both TLR7 and TLR9 signaling in B cell, and patients with autosomal dominant hyper IgE syndromes (AD-HIES) due to STAT3 mutations having defective TLRs response in B cells. However, how STAT3 affects its target genes and the downstream signaling pathways in B cell upon TLRs stimulation remains unclarified on a genome-wide level. ChIP-seq and RNA-seq was used in this study to identify the STAT3 targets in response to TLRs stimulation in human B cell. STAT3 ChIP-seq results showed a total of 611 and 2,289 differential STAT3-binding sites in human B cell after TLR7 and TLR9 agonists stimulation, respectively. RNA-seq results showed 1,186 and 1,775 differentially expressed genes after TLR7 and TLR9 activation, respectively. We identified 47 primary STAT3 target genes after TLR7 activation and 189 target genes after TLR9 activation in B cell by integration of STAT3 ChIP-seq and RNA-seq data. Among these STAT3 primary targets, we identified 7 TFs and 18 TFs for TLR7 and TLR9 response, respectively. Besides, we showed that STAT3 might regulate TLR9, but not TLR7 response in B cells through directly regulating integrin signaling pathway, which might further affect the antagonism between TLR7 and TLR9 signaling in B cell. Our study provides insights into the molecular mechanism of human TLRs response in B cell and how it can be regulated, which helps to better understand and modulate TLR-mediated pathogenic immune responses in B cell.


Assuntos
Receptor 7 Toll-Like , Receptor Toll-Like 9 , Sequenciamento de Cromatina por Imunoprecipitação , Humanos , RNA-Seq , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Receptor 7 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
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