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1.
Nature ; 590(7846): 433-437, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568814

RESUMO

Emissions of ozone-depleting substances, including trichlorofluoromethane (CFC-11), have decreased since the mid-1980s in response to the Montreal Protocol1,2. In recent years, an unexpected increase in CFC-11 emissions beginning in 2013 has been reported, with much of the global rise attributed to emissions from eastern China3,4. Here we use high-frequency atmospheric mole fraction observations from Gosan, South Korea and Hateruma, Japan, together with atmospheric chemical transport-model simulations, to investigate regional CFC-11 emissions from eastern China. We find that CFC-11 emissions returned to pre-2013 levels in 2019 (5.0 ± 1.0 gigagrams per year in 2019, compared to 7.2 ± 1.5 gigagrams per year for 2008-2012, ±1 standard deviation), decreasing by 10 ± 3 gigagrams per year since 2014-2017. Furthermore, we find that in this region, carbon tetrachloride (CCl4) and dichlorodifluoromethane (CFC-12) emissions-potentially associated with CFC-11 production-were higher than expected after 2013 and then declined one to two years before the CFC-11 emissions reduction. This suggests that CFC-11 production occurred in eastern China after the mandated global phase-out, and that there was a subsequent decline in production during 2017-2018. We estimate that the amount of the CFC-11 bank (the amount of CFC-11 produced, but not yet emitted) in eastern China is up to 112 gigagrams larger in 2019 compared to pre-2013 levels, probably as a result of recent production. Nevertheless, it seems that any substantial delay in ozone-layer recovery has been avoided, perhaps owing to timely reporting3,4 and subsequent action by industry and government in China5,6.

2.
Small ; 19(2): e2200712, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36385593

RESUMO

Rapid spread of infectious diseases is a global threat and has an adverse impact on human health, livelihood, and economic stability, as manifested in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Even though people wear a face mask as protective equipment, direct disinfection of the pathogens is barely feasible, which thereby urges the development of biocidal agents. Meanwhile, repetitive respiration generates temperature variation wherein the heat is regrettably wasted. Herein, a biocidal ZnO nanorod-modified paper (ZNR-paper) composite that is 1) integrated on a face mask, 2) harvests waste breathing-driven thermal energy, 3) facilitates the pyrocatalytic production of reactive oxygen species (ROS), and ultimately 4) exhibits antibacterial and antiviral performance is proposed. Furthermore, in situ generated compressive/tensile strain of the composite by being attached to a curved mask is investigated for high pyroelectricity. The anisotropic ZNR distortion in the bent composite is verified with changes in ZnO bond lengths and OZnO bond angles in a ZnO4 tetrahedron, resulting in an increased polarization state and possibly contributing to the following pyroelectricity. The enhanced pyroelectric behavior is demonstrated by efficient ROS production and notable bioprotection. This study exploring the pre-strain effect on the pyroelectricity of ZNR-paper might provide new insights into the piezo-/pyroelectric material-based applications.


Assuntos
COVID-19 , Óxido de Zinco , Humanos , COVID-19/prevenção & controle , Óxido de Zinco/química , Máscaras , Espécies Reativas de Oxigênio , Respiração
3.
Parasite Immunol ; 44(9): e12938, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35689825

RESUMO

The chemokine receptor CCR7 is a well-established homing receptor for dendritic cells (DCs) and T-cells. Interaction with the CCL19 and CCL21 ligands promotes priming of immune responses in lymphoid tissues; however, the mechanism underlying CCR7-induced immune responses against helminth parasite infection remains unknown. Thus, we examined the role of CCR7 in generating protective immune responses against intracellular Trichinella spiralis infection. The results showed significantly increased CCR7, CCL19 and CCL21 expression in the muscle tissue compared to that in the intestinal tissue in T. spiralis-infected mice. The CCR7-expressing DC population increased in the mesenteric and peripheral lymph nodes (PLNs) during T. spiralis infection. Notably, the number of CCR7-expressing cells in PLNs increased by more than 30% at 28 days post-infection; however, this increase was significantly inhibited in CCR7-blocked mice treated with CCR7-specific antibodies. T helper 2 (Th2)-and regulatory T (Treg )-related cytokine levels were also reduced by CCR7-specific antibody treatment. CCR7-blocked mice lost their resistance to T. spiralis infection in the muscle phase but not in the intestinal phase. Furthermore, fewer eosinophils around the nurse cells and reduced total and T. spiralis-specific IgE in the serum were observed in CCR7-blocked mice compared to those infected with only T. spiralis. CCR7 blockade led to the T. spiralis infection-induced suppression of Th2- and Treg -related cytokine production in vitro. These results suggest that CCR7 in DCs might play an essential role in host defence mechanisms against T. spiralis infection, particularly in the muscle stage of the infection, by accelerating Th2 and Treg cell responses.


Assuntos
Trichinella spiralis , Triquinelose , Animais , Citocinas/metabolismo , Células Dendríticas , Camundongos , Receptores CCR7/metabolismo
4.
Int J Mol Sci ; 23(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35216506

RESUMO

Protein tyrosine kinase 7 (PTK7), a catalytically defective receptor protein tyrosine kinase, is upregulated in tumor tissues and cell lines of esophageal squamous cell carcinoma (ESCC). We showed that PTK7 plays an oncogenic role in various ESCC cell lines. However, its role as an oncogene has not been demonstrated in vivo. Here, we examined the influence of PTK7 on the tumorigenic potential of ESCC KYSE-30 cells, which are known to establish xenograft tumors. Overexpression of PTK7 enhanced the proliferation, adhesion, wound healing, and migration of KYSE-30 cells, and these effects were reversed by the knockdown of PTK7. PTK7 overexpression and knockdown, respectively, increased and decreased the tyrosine phosphorylation of cellular proteins and the phosphorylation of ERK, AKT, and FAK, which are important for cell proliferation, survival, adhesion, and migration. Additionally, PTK7 overexpression and silencing, respectively, increased and decreased the weight, volume, and number of Ki-67-positive proliferating cells in xenograft tumors of KYSE-30 cells. Therefore, we propose that PTK7 plays an important role in the tumorigenesis of ESCC cells in vivo and is a potential therapeutic target for ESCC.


Assuntos
Carcinogênese/genética , Moléculas de Adesão Celular/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Xenoenxertos/metabolismo , Oncogenes/genética , Receptores Proteína Tirosina Quinases/genética , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Fenótipo , Fosforilação/genética , Transdução de Sinais/genética
5.
J Ind Microbiol Biotechnol ; 48(5-6)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33904924

RESUMO

Probiotics are beneficial microorganisms, and the evaluation of their safety for human use in the food industry has become critical. This study examines the safety of Bacillus coagulans IDCC 1201 isolated from green malt by analyzing its genomic and phenotypic characteristics and determining its toxicity. The presence of antibiotic resistance and toxigenic genes and gene transferability were investigated using whole-genome analysis. The strain's hemolytic and enzyme activities, minimum inhibitory concentrations of antibiotics, and biogenic amine and D-lactate production were also examined. Furthermore, the principal properties of B. coagulans IDCC 1201 as probiotics, such as resistance to abiotic stress and intestinal adhesion, were studied. The whole-genome analysis demonstrated that B. coagulans IDCC 1201 had no antibiotic resistance or toxigenic genes; the strain was susceptible to the nine antibiotics proposed by the European Food Safety Authority. Moreover, this strain lacked hemolytic and ß-glucuronidase activities. Additionally, it was confirmed that B. coagulans IDCC 1201 produced undesirable metabolites, including biogenic amines or D-lactate, at a safe level. Finally, the strain exhibited functional potential as a probiotic in terms of abiotic tolerance, such as bile tolerance and intestinal adhesion in in vitro experiments. In conclusion, B. coagulans IDCC 1201 can be considered as a safe probiotic with regard to human health.


Assuntos
Bacillus coagulans/efeitos dos fármacos , Bacillus coagulans/genética , Probióticos , Células A549 , Animais , Antibacterianos/farmacologia , Aminas Biogênicas/metabolismo , Linhagem Celular , Resistência Microbiana a Medicamentos , Feminino , Estudo de Associação Genômica Ampla , Instabilidade Genômica , Genômica , Células HaCaT , Células Endoteliais da Veia Umbilical Humana , Humanos , Ácido Láctico/metabolismo , Metaboloma , Testes de Sensibilidade Microbiana , Modelos Animais , Filogenia , Probióticos/toxicidade , Ratos , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
6.
Sensors (Basel) ; 21(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34450722

RESUMO

The consumption of seaweed is increasing year by year worldwide. Therefore, the foreign object inspection of seaweed is becoming increasingly important. Seaweed is mixed with various materials such as laver and sargassum fusiforme. So it has various colors even in the same seaweed. In addition, the surface is uneven and greasy, causing diffuse reflections frequently. For these reasons, it is difficult to detect foreign objects in seaweed, so the accuracy of conventional foreign object detectors used in real manufacturing sites is less than 80%. Supporting real-time inspection should also be considered when inspecting foreign objects. Since seaweed requires mass production, rapid inspection is essential. However, hyperspectral imaging techniques are generally not suitable for high-speed inspection. In this study, we overcome this limitation by using dimensionality reduction and using simplified operations. For accuracy improvement, the proposed algorithm is carried out in 2 stages. Firstly, the subtraction method is used to clearly distinguish seaweed and conveyor belts, and also detect some relatively easy to detect foreign objects. Secondly, a standardization inspection is performed based on the result of the subtraction method. During this process, the proposed scheme adopts simplified and burdenless calculations such as subtraction, division, and one-by-one matching, which achieves both accuracy and low latency performance. In the experiment to evaluate the performance, 60 normal seaweeds and 60 seaweeds containing foreign objects were used, and the accuracy of the proposed algorithm is 95%. Finally, by implementing the proposed algorithm as a foreign object detection platform, it was confirmed that real-time operation in rapid inspection was possible, and the possibility of deployment in real manufacturing sites was confirmed.


Assuntos
Corpos Estranhos , Alga Marinha , Algoritmos , Imageamento Hiperespectral , Verduras
7.
Int J Cancer ; 146(10): 2822-2828, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472018

RESUMO

Kirsten rat sarcoma (KRAS) mutant cancers, which constitute the vast majority of pancreatic tumors, are characterized by their resistance to established therapies and high mortality rates. Here, we developed a novel and extremely effective combinational therapeutic approach to target KRAS mutant tumors through the generation of a cytotoxic oxidative stress. At high concentrations, vitamin C (VC) is known to provoke oxidative stress and selectively kill KRAS mutant cancer cells, although its effects are limited when it is given as monotherapy. We found that the combination of VC and the oxidizing drug arsenic trioxide (ATO) is an effective therapeutic treatment modality. Remarkably, its efficiency is dependent on chirality of VC as its enantiomer d-optical isomer of VC (d-VC) is significantly more potent than the natural l-optical isomer of VC. Thus, our results demonstrate that the oxidizing combination of ATO and d-VC is a promising approach for the treatment of KRAS mutant human cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Trióxido de Arsênio/farmacologia , Ácido Ascórbico/farmacologia , Neoplasias Experimentais , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Ácido Ascórbico/química , Sinergismo Farmacológico , Células HCT116 , Humanos , Isomerismo , Camundongos Nus , Mutação , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Adv Skin Wound Care ; 33(3): 1-11, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32058443

RESUMO

OBJECTIVE: To conduct a meta-analysis of the literature on training programs that aimed to improve nurses' pressure injury management skills. METHODS: Literature searches were conducted using Ovid-MEDLINE, Cochrane Library, CINAHL, and Korean databases. The search terms used were: (nurse* AND ((pressure OR decubitus) AND (ulcer* OR injur*)) OR bed sore OR bedsore OR decubitus) AND (program* OR training)). Random-effects models were used to calculate the standardized mean difference and odds ratios, with 95% confidence intervals (CIs) to analyze the effects. MAIN RESULTS: Initial searches yielded 1,067 studies. Of these, 23 met the selection criteria. Nurses' knowledge (standard mean difference, 1.23; 95% CI, 0.50-1.96; P < .001), visual discrimination ability (standard mean difference, 1.13; 95% CI, 0.88-1.38; P < .001), and clinical judgment (odds ratio, 1.52; 95% CI, 1.46-1.57; P < .001) improved after the programs. CONCLUSIONS: Pressure injury training programs can improve nurses' competency. The results from this study indicate that such programs may help improve nurses' knowledge, visual discrimination ability, and clinical judgment and can be considered continuing education programs. However, large-scale studies are needed to confirm this conclusion.


Assuntos
Educação em Enfermagem/métodos , Profissionais de Enfermagem/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Úlcera por Pressão/enfermagem , Ferimentos e Lesões/enfermagem , Competência Clínica , Feminino , Humanos , Masculino , Papel do Profissional de Enfermagem , Úlcera por Pressão/diagnóstico , Estados Unidos
9.
Bioorg Med Chem Lett ; 29(11): 1350-1356, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30954427

RESUMO

A pyrrolo[1,2-a]pyrazine-based chemical territory was expanded via construction of new chemical library with distinctive substitution patterns, which was made possible by regiodivergent electrophilic acylation followed by aldol condensation. Biological screening of the compounds in this class revealed that the viability of human lymphoma U937 cells was strongly inhibited by 6b with a methoxy group at the o-position of the aromatic ring, but not by compounds 6t-w bearing a halogen at the o-position. Furthermore, 6x having a 2,4-dimethoxyphenyl group inhibited the survival of U937 cells more potently than 6b. In contrast, 6y possessing a 2,5-dimethoxyphenyl moiety did not show effective inhibition, implying the importance of orientation of the substituent(s) around the benzene ring. The anticancer action of 6x with safe therapeutic window could be associated with the FTase-p38 signaling axis.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células U937
10.
Korean J Parasitol ; 57(2): 117-125, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31104403

RESUMO

Malarial infection induces tissue hypoxia in the host through destruction of red blood cells. Tissue hypoxia in malarial infection may increase the activity of HIF1α through an intracellular oxygen-sensing pathway. Activation of HIF1α may also induce vascular endothelial growth factor (VEGF) to trigger angiogenesis. To investigate whether malarial infection actually generates hypoxia-induced angiogenesis, we analyzed severity of hypoxia, the expression of hypoxia-related angiogenic factors, and numbers of blood vessels in various tissues infected with Plasmodium berghei. Infection in mice was performed by intraperitoneal injection of 2×106 parasitized red blood cells. After infection, we studied parasitemia and survival. We analyzed hypoxia, numbers of blood vessels, and expression of hypoxia-related angiogenic factors including VEGF and HIF1α. We used Western blot, immunofluorescence, and immunohistochemistry to analyze various tissues from Plasmodium berghei-infected mice. In malaria-infected mice, parasitemia was increased over the duration of infection and directly associated with mortality rate. Expression of VEGF and HIF1α increased with the parasitemia in various tissues. Additionally, numbers of blood vessels significantly increased in each tissue type of the malaria-infected group compared to the uninfected control group. These results suggest that malarial infection in mice activates hypoxia-induced angiogenesis by stimulation of HIF1α and VEGF in various tissues.


Assuntos
Células Endoteliais/patologia , Hipóxia , Malária/patologia , Neovascularização Patológica , Plasmodium berghei/crescimento & desenvolvimento , Animais , Western Blotting , Modelos Animais de Doenças , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Imuno-Histoquímica , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Parasitemia/parasitologia , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular/análise
11.
Biochem Biophys Res Commun ; 496(3): 826-833, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29378184

RESUMO

Breast cancer is the most frequently diagnosed life-threatening cancer in women. Triple-negative breast cancer (TNBC) has an aggressive clinical behavior, but the treatment of TNBC remains challenging. MicroRNAs (miRNAs) have emerged as a potential target for the diagnosis, therapy and prognosis of breast cancer. However, the precise role of miRNAs and their targets in breast cancer remain to be elucidated. Here we show that miR-218 is downregulated and miR-129 is upregulated in TNBC samples and their expressions confer prognosis to patients. Gain-of-function and loss-of-function analysis reveals that miR-218 has a tumor suppressive activity, while miR-129 acts as an oncomir in breast cancer. Notably, miR-218 and miR-129 directly target Lamin B1 and Lamin A, respectively, which are also found to be deregulated in human breast tumors. Finally, we demonstrate Lamins as the major factors in reliable miR-218 and miR-129 functions for breast cancer progression. Our findings uncover a new miRNA-mediated regulatory network for different Lamins and provide a potential therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Laminas/metabolismo , MicroRNAs/metabolismo , Proliferação de Células , Humanos , Células MCF-7 , Invasividade Neoplásica/patologia
12.
Int J Med Sci ; 15(8): 802-807, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30008590

RESUMO

Introduction:Trichinella spiralis establishes a chronic infection in skeletal muscle by developing nurse cells within muscle fibers. During symbiosis in host, changes in the muscle fibers and inflammation may affect muscle function. Methods: We investigated muscle strength and inflammation in T. spiralis-infected mice during 1 to 48 weeks after infection. Results: Muscle strength decreased compared to that in uninfected control mice during the late infection stage. Additionally, inflammatory related cytokines increased significantly during early stage of infection and then rapidly decreased. In pathological study, nuclear infiltration maintained from the early infection stage to chronic infection stage. Moreover, vacuoles and eosinophil infiltration were observed in infected muscle in chronic stage. Conclusion: These results suggest that infection by T. spiralis significantly affects muscle function was continuously being weakness because vacuoles formation and maintained nucleus and eosinophil infiltration during chronic phase of T. spiralis infection.


Assuntos
Força Muscular , Trichinella spiralis/patogenicidade , Triquinelose/fisiopatologia , Animais , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético , República da Coreia
13.
Biosci Biotechnol Biochem ; 82(7): 1134-1142, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29570000

RESUMO

The goals of this research were to develop a rapid single-walled carbon nanotube (SWCNT)-based biosensor and to employ it to commercial food products for Ara h1 detection. The SWCNT-based biosensor was fabricated with SWCNTs immobilized with antibody (pAb) through hybridization of 1-pyrenebutanoic acid succinimidyl ester (1-PBASE) as a linker. The resistance difference (ΔR) was calculated by measuring linear sweep voltammetry (LSV) using a potentiostat. Resistance values increased as the concentration of Ara h1 increased over the range of 1 to 105 ng/L. The specific binding of anti-Ara h1 pAb to antigen including Ara h1 was confirmed by both indirect ELISA kit and biosensor assay. The biosensor was exposed to extracts prepared from commercial processed food containing peanuts, or no peanuts, and could successfully distinguish the peanut containing foods. In addition, the application of present biosensor approach documented the precise detection of Ara h1 concentrations in commercially available peanut containing foods.


Assuntos
Antígenos de Plantas/análise , Arachis/química , Técnicas Biossensoriais , Técnicas Eletroquímicas/instrumentação , Análise de Alimentos/métodos , Manipulação de Alimentos , Glicoproteínas/análise , Nanotubos de Carbono , Proteínas de Plantas/análise , Arachis/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Limite de Detecção , Proteínas de Membrana , Microscopia Eletrônica de Transmissão , Hipersensibilidade a Amendoim/etiologia , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/prevenção & controle , Pirenos/química , Succinimidas/química
14.
EMBO Rep ; 16(10): 1288-98, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26303947

RESUMO

The histone H3K27 demethylase, UTX, is a known component of the H3K4 methyltransferase MLL complex, but its functional association with H3K4 methylation in human cancers remains largely unknown. Here we demonstrate that UTX loss induces epithelial-mesenchymal transition (EMT)-mediated breast cancer stem cell (CSC) properties by increasing the expression of the SNAIL, ZEB1 and ZEB2 EMT transcription factors (EMT-TFs) and of the transcriptional repressor CDH1. UTX facilitates the epigenetic silencing of EMT-TFs by inducing competition between MLL4 and the H3K4 demethylase LSD1. EMT-TF promoters are occupied by c-Myc and MLL4, and UTX recognizes these proteins, interrupting their transcriptional activation function. UTX decreases H3K4me2 and H3 acetylation at these promoters by forming a transcriptional repressive complex with LSD1, HDAC1 and DNMT1. Taken together, our findings indicate that UTX is a prominent tumour suppressor that functions as a negative regulator of EMT-induced CSC-like properties by epigenetically repressing EMT-TFs.


Assuntos
Repressão Epigenética , Transição Epitelial-Mesenquimal , Histona Desmetilases/genética , Células-Tronco Neoplásicas/fisiologia , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Neoplasias da Mama , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 1/genética , Histona Desacetilase 1/fisiologia , Histona Desmetilases/fisiologia , Humanos , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
J Transl Med ; 14(1): 191, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27350539

RESUMO

BACKGROUND: Foxp3 is a key regulator of the development and function of regulatory T cells (Tregs), and its expression is thought to be T cell-restricted. We found that B cells in mice can express Foxp3 and B cells expressing Foxp3 may play a role in preventing the development of collagen-induced arthritis (CIA) in DBA/1J mice. METHODS: Foxp3 expression was modulated in CD19(+) B cells by transfection with shRNA or using an over-expression construct. In addition, Foxp3-transfected B cells were adoptively transferred to CIA mice. We found that LPS or anti-IgM stimulation induced Foxp3 expression in B cells. Foxp3-expressing B cells were found in the spleens of mice. RESULTS: Over-expression of Foxp3 conferred a contact-dependent suppressive ability on proliferation of responder T cells. Down-regulation of Foxp3 by shRNA caused a profound induction in proliferation of responder T cells. Adoptive transfer of Foxp3(+)CD19(+) B cells attenuated the clinical symptoms of CIA significantly with concomitant suppression of IL-17 production and enhancement of Foxp3 expression in CD4(+) T cells from splenocytes. CONCLUSION: Our data indicate that Foxp3 expression is not restricted to T cells. The expression of Foxp3 in B cells is critical for the immunoregulation of T cells and limits autoimmunity in a mouse model.


Assuntos
Transferência Adotiva , Artrite Experimental/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B Reguladores/imunologia , Fatores de Transcrição Forkhead/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Artrite Experimental/patologia , Comunicação Celular , Linhagem Celular Tumoral , Proliferação de Células , Imunoglobulina M/metabolismo , Terapia de Imunossupressão , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos DBA , Baço/patologia , Transfecção
16.
Allergy Asthma Proc ; 37(2): 141-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26932171

RESUMO

BACKGROUND: Acanthamoeba and their proteins can elicit severe allergic airway inflammation in experimental mice. OBJECTIVE: Although Acanthamoeba can induce severe allergic airway inflammation in mice, there is no allergenicity data for humans. METHODS: We performed a skin-prick test on 65 patients with chronic cough by using 54 previously known allergens and Acanthamoeba excretory-secretory proteins and enzyme-linked immunosorbent assay on 34 patients to evaluate Acanthamoeba-specific serum immunoglobulin (Ig) levels. To detect a novel Acanthamoeba allergen, Western blot analysis was performed on serum from patients who reacted positively to Acanthamoeba or some pollen allergens. RESULTS: After skin-prick testing, 29 patients (44.6%) showed positive reactions to one or more common aeroallergens. Acanthamoeba allergenicity was evaluated in 4 of 65 subjects (6.1%). An Acanthamoeba-positive reaction was closely related to several pollen allergens, especially willow tree, poplar, elm, oak, velvet grass, and cockroach. Average levels of Acanthamoeba-specific IgG subtypes in patient serum did not differ compared with healthy subjects; however, Acanthamoeba-specific IgE titers of patients were significantly higher than in healthy subjects. IgE antibodies of patients who tested positive in the skin-prick test reacted strongly to the 15 kDa excretory-secretory protein. Moreover, these antigens also reacted with those who tested positive in the skin-prick test to pollens. CONCLUSION: Taken together, our results indicated that some patients with allergy showed a positive response to the skin-prick test and that they also have high IgE serum levels. However, further experimental investigation is warranted because our preliminary findings indicated that Acanthamoeba might be a new allergen in humans.


Assuntos
Acanthamoeba/imunologia , Alérgenos/imunologia , Antígenos de Protozoários/imunologia , Tosse/imunologia , Hipersensibilidade/imunologia , Adulto , Idoso , Especificidade de Anticorpos/imunologia , Estudos de Casos e Controles , Doença Crônica , Tosse/diagnóstico , Feminino , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Testes Cutâneos , Adulto Jovem
17.
J Nanosci Nanotechnol ; 15(10): 7929-34, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26726442

RESUMO

Human mesenchymal stem cells (MSCs) have the capacity for self-renewal and maintain pluripotency, which is defined by their ability to differentiate into cells such as osteoblasts, neurons, and glial cells. In this study, we report a method for defining the status of human MSCs based on electrochemical detection systems. Gold nano-dot structures were fabricated using a nanoporous alumina mask, and the structural formations were confirmed by scanning electron microscopy (SEM). Human MSCs were allowed to attach to RGD (Arg-Gly-Asp) peptide nanopatterned surfaces, and electrochemical tools were applied to the MSCs attached on the chip surface. The cultured MSCs were shown to differentiate into neural cell types, as indicated by immunocytochemical staining for tyrosine hydroxylase and beta tubulin III. Following treatment with basic fibroblast growth factor (bFGF) for 14 days, most of the B10 cells exhibited bipolar or multipolar morphology with branched processes, and the proportion of B10 cells expressing neuronal cell markers considerably increased. Electrophysiological recordings from MSCs treated with bFGF for 5-14 days were examined with cyclic voltammetry, and the electrochemical signals were shown to increase during differentiation from MSCs to neuronal cells. This human MSC cell line is a useful tool for studying organogenesis, specifically neurogenesis, and in addition, the cell line provides a valuable source of cells for cell therapy. The electrochemical measurement system proposed here could be utilized in electrical cell chips for numerous applications, including cell differentiation, disease diagnosis, drug detection, and on-site monitoring.


Assuntos
Óxido de Alumínio/química , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Ouro/química , Células-Tronco Mesenquimais/metabolismo , Nanoestruturas/química , Antígenos de Diferenciação/biossíntese , Linhagem Celular , Humanos , Células-Tronco Mesenquimais/citologia
18.
Immunology ; 142(4): 573-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24495300

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease in which abnormal immune responses are mediated by tissue-binding autoantibodies and immune complex deposition. Because most SLE patients are women of child-bearing age, oestrogen has been suggested to play an important role in SLE pathogenesis. One proposed role is to induce B-cell activation, culminating in increased autoantibody production. Interleukin-21 (IL-21) has been shown to be crucial in the differentiation of activated B cells into plasma cells. We therefore hypothesized that oestrogen up-regulates IL-21 production and induces subsequent B-cell activation in SLE patients. Peripheral blood was obtained from 22 SLE patients and 16 healthy controls. Expression levels of IL-21 and its receptor in serum, peripheral blood mononuclear cells, and CD4(+) T cells were higher in SLE patients than in healthy controls. Exposure of CD4(+) T cells from SLE patients to 17ß-oestradiol led to a dose- and time-dependent increase in IL-21 expression, which was abolished in the presence of mitogen-activated protein kinase (MAPK) (MAPK kinase, p38, Jun N-terminal kinase) inhibitors. B cells from healthy controls showed increased antibody production when they were co-cultured with oestrogen-treated CD4(+) T cells from SLE patients. Treatment with IL-21 antibody abrogated the increased antibody production of the co-culture systems. This study revealed the association between oestrogen and IL-21 in SLE patients. Oestrogen up-regulates IL-21 expression of CD4(+) T cells via MAPK-dependent pathways in SLE patients, which in turn induces increased antibody production by B cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Estradiol/farmacologia , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucinas/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Formação de Anticorpos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , MAP Quinases Reguladas por Sinal Extracelular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Interleucinas/biossíntese , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Pessoa de Meia-Idade , Plasmócitos/imunologia , Plasmócitos/metabolismo , Plasmócitos/patologia
19.
Environ Sci Technol ; 48(1): 491-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24298975

RESUMO

The sources of halogenated compounds in East Asia associated with stratospheric ozone depletion and climate change are relatively poorly understood. High-precision in situ measurements of 18 halogenated compounds and carbonyl sulfide (COS) made at Gosan, Jeju Island, Korea, from November 2007 to December 2011 were analyzed by a positive matrix factorization (PMF). Seven major industrial sources were identified from the enhanced concentrations of halogenated compounds observed at Gosan and corresponding concentration-based source contributions were also suggested: primary aluminum production explaining 37% of total concentration enhancements, solvent usage of which source apportionment is 25%, fugitive emissions from HCFC/HFC production with 11%, refrigerant replacements (9%), semiconductor/electronics industry (9%), foam blowing agents (6%), and fumigation (3%). Statistical trajectory analysis was applied to specify the potential emission regions for seven sources using back trajectories. Primary aluminum production, solvent usage and fugitive emission sources were mainly contributed by China. Semiconductor/electronics sources were dominantly located in Korea. Refrigerant replacement, fumigation and foam blowing agent sources were spread throughout East Asian countries. The specified potential source regions are consistent with country-based consumptions and emission patterns, verifying the PMF analysis results. The industry-based emission sources of halogenated compounds identified in this study help improve our understanding of the East Asian countries' industrial contributions to halogenated compound emissions.


Assuntos
Poluentes Atmosféricos/análise , Mudança Climática , Monitoramento Ambiental/métodos , Hidrocarbonetos Halogenados/análise , Indústrias , Modelos Teóricos , Ásia Oriental , Análise dos Mínimos Quadrados , Estações do Ano
20.
J Immunol ; 189(2): 1062-71, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22696440

RESUMO

Retinoic acid is the active vitamin A derivative and is well-known to have diverse immunomodulatory actions. In this study, we investigated the impact of all-trans retinoic acid (ATRA), a biologic key metabolite of vitamin A, on the development of arthritis and the pathophysiologic mechanisms by which ATRA might have antiarthritic effects in animal model of rheumatoid arthritis (RA; collagen-induced arthritis [CIA] in DBA/1J mice). We showed that treatment with ATRA markedly suppressed the clinical and histologic signs of arthritis in the CIA mice. It reduced the expression of IL-17 in the arthritic joints. Interestingly, Foxp3(+) regulatory T cells were markedly increased and IL-17-producing CD4(+) T cells (Th17 cells) were decreased in the spleens of ATRA-treated mice. In vitro treatment with ATRA induced the expression of Foxp3 and repressed the IL-17 expression in the CD4(+) T cells in mice. ATRA suppressed the production of total IgG and IgG2a in splenocytes that were stimulated by LPS. It also reduced serum levels of total IgG and IgG2 anti-collagen Abs and germinal center formation in CIA mice. In addition, the ATRA-treated mice showed decreased osteoclast formation in arthritic joints. Moreover, ATRA downregulated the expression of receptor activator of NF-κB ligand, the leading player of osteoclastogenesis, in the CD4(+) T cells and fibroblast-like synoviocytes from patients with RA. Furthermore, ATRA prevented both human monocytes and mice bone marrow-derived monocytes/macrophage cells from differentiating into osteoclasts. These data suggest ATRA might be an effective treatment modality for RA patients.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Mediadores da Inflamação/uso terapêutico , Tretinoína/uso terapêutico , Animais , Artrite Reumatoide/patologia , Bovinos , Colágeno Tipo II/toxicidade , Modelos Animais de Doenças , Imunidade Humoral/efeitos dos fármacos , Imunidade Humoral/imunologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Mediadores da Inflamação/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos DBA , Osteoclastos/efeitos dos fármacos , Osteoclastos/imunologia , Osteoclastos/patologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/patologia , Tretinoína/administração & dosagem
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