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1.
Environ Monit Assess ; 191(7): 459, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236703

RESUMO

The aim of the study is to create a suitable map for wind energy projects in a rural area. The primary goal here is to show a methodology using automatic object extraction of the target classes of buildings, vegetation, and ground. The secondary goal is to identify the potential effects for wind turbine sites based on four criteria: Wind speed, Slope, Building, and Vegetation using the fuzzy analytical hierarchy process (FAHP). This paper discusses two important situations for wind energy projects. The first strategy is to just determine the best suitable site locations of wind turbines, while the second strategy determines the locations of wind turbines with minimal negative effects on the rural area. The proposed approach is tested using the data obtained from a multi-sensor system in Evrencik, Turkey. In preliminary phases of renewable energy projects, successful results are dependent on evaluating the potential site's suitability with criteria such as social, environmental, physical, and economic conditions. Furthermore, an accuracy analysis is performed on the automatically extracted target classes for the study area, yielding a value of 89% in the remote sensing section of the study. Moreover, for the GIS section of the study, suitable and unsuitable areas are identified, and the suitability levels of the remaining areas are determined for the two strategies. According to the results, 11% of the areas are found to have high, moderate, and low suitability levels, and 89% are unsuitable for the first strategy, whereas these rates are, respectively, 2% and 98% for the second strategy.


Assuntos
Sistemas de Informação Geográfica , Mapeamento Geográfico , Tecnologia de Sensoriamento Remoto/métodos , Vento , Monitoramento Ambiental , Fenômenos Físicos , Turquia
2.
Eur J Immunol ; 47(11): 1880-1889, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28837222

RESUMO

Protein kinase A (PKA) is a holoenzyme composed of a regulatory subunit dimer and two catalytic subunits and regulates numerous cellular functions including immune cell activity. There are two major catalytic subunit genes, PRKACA and PRKACB encoding the catalytic subunits Cα and Cß. The PRKACB gene encodes several splice variants including Cß2, which is enriched in T-, B- and natural killer cells. Cß2 is significantly larger (46 kDa) than any other C splice variant. In this study we characterized mice ablated for the Cß2 protein demonstrating a significantly reduced cAMP-induced catalytic activity of PKA in the spleenocytes, lymphocytes and thymocytes. We also observed a significantly increased number of CD62L-expressing CD4+ and CD8+ T cells in LNs, accompanied by increased susceptibility to systemic inflammation by the Cß2 ablated mice. The latter was reflected in an elevated sensitivity to collagen-induced arthritis (CIA), as well as higher concentration of TNF-α and lower concentration of IL-10 in response to LPS challenges. We suggest a role of Cß2 in regulating innate as well as adaptive immune sensitivity in vivo.


Assuntos
Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/imunologia , Inflamação/enzimologia , Inflamação/imunologia , Animais , Artrite Experimental/enzimologia , Artrite Experimental/imunologia , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/enzimologia , Linfócitos T CD8-Positivos/imunologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Adv Sci (Weinh) ; 11(23): e2401513, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602454

RESUMO

Transgenic mice expressing human major histocompatibility complex class II (MHCII) risk alleles are widely used in autoimmune disease research, but limitations arise due to non-physiologic expression. To address this, physiologically relevant mouse models are established via knock-in technology to explore the role of MHCII in diseases like rheumatoid arthritis. The gene sequences encoding the ectodomains are replaced with the human DRB1*04:01 and 04:02 alleles, DRA, and CD74 (invariant chain) in C57BL/6N mice. The collagen type II (Col2a1) gene is modified to mimic human COL2. Importantly, DRB1*04:01 knock-in mice display physiologic expression of human MHCII also on thymic epithelial cells, in contrast to DRB1*04:01 transgenic mice. Humanization of the invariant chain enhances MHCII expression on thymic epithelial cells, increases mature B cell numbers in spleen, and improves antigen presentation. To validate its functionality, the collagen-induced arthritis (CIA) model is used, where DRB1*04:01 expression led to a higher susceptibility to arthritis, as compared with mice expressing DRB1*04:02. In addition, the humanized T cell epitope on COL2 allows autoreactive T cell-mediated arthritis development. In conclusion, the humanized knock-in mouse faithfully expresses MHCII, confirming the DRB1*04:01 alleles role in rheumatoid arthritis and being also useful for studying MHCII-associated diseases.


Assuntos
Alelos , Antígenos de Diferenciação de Linfócitos B , Artrite Reumatoide , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Antígenos de Histocompatibilidade Classe II , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Animais , Camundongos , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/imunologia , Humanos , Técnicas de Introdução de Genes/métodos , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Artrite Experimental/genética , Artrite Experimental/imunologia , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Colágeno Tipo II/genética , Colágeno Tipo II/imunologia
4.
FEBS Open Bio ; 12(1): 163-174, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34698439

RESUMO

In humans, there are two forms of glutaminase (GLS), designated GLS1 and GLS2. These enzymes catalyse the conversion of glutamine to glutamate. GLS1 exists as two isozymes: kidney glutaminase (KGA) and glutaminase C (GAC). Several GLS inhibitors have been identified, of which DON (6-diazo-5-oxonorleucine), BPTES (bis-2-(5-phenylacetamido-1, 3, 4-thiadiazol-2-yl) ethyl sulphide), 968 (5-(3-Bromo-4-(dimethylamino)phenyl)-2,2-dimethyl-2,3,5,6-tetrahydrobenzo[a]phenanthridin-4(1H)-one) and CB839 (Telaglenastat) are the most widely used. However, these inhibitors have variable efficacy, specificity and bioavailability in research and clinical settings, implying the need for novel and improved GLS inhibitors. Based on this need, a diverse library of 28,000 compounds from Enamine was screened for inhibition of recombinant, purified GAC. From this library, one inhibitor designated compound 19 (C19) was identified with kinetic features revealing allosteric inhibition of GAC in the µm range. Moreover, C19 inhibits anti-CD3/CD28-induced CD4+ T-cell proliferation and cytokine production with similar or greater potency as compared to BPTES. Taken together, our data suggest that C19 has the potential to modulate GLS1 activity and alter metabolic activity of T cells.


Assuntos
Glutaminase , Tiadiazóis , Proliferação de Células , Inibidores Enzimáticos/farmacologia , Glutaminase/metabolismo , Glutamina/metabolismo , Humanos , Tiadiazóis/metabolismo , Tiadiazóis/farmacologia
5.
Front Immunol ; 12: 631249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33708221

RESUMO

The most commonly used strains in experimental research, including genetically modified strains, are C57BL/6 mice. However, so far, no reliable model for rheumatoid arthritis is available, mainly due to the restriction by the MHC class II haplotype H-2b. Collagen-induced arthritis (CIA) is the most widely used animal model of rheumatoid arthritis, but C57BL/6 strain is resistant to CIA because there is no collagen II peptide associated with H-2b. To establish a rheumatoid arthritis model in C57BL/6 mice, we immunized C57BL/6NJ (B6N) mice with human cartilage oligomeric matrix protein (COMP), which induced severe arthritis with high incidence, accompanied by a strong auto-antibody response. Native COMP was required, as denatured COMP lost its ability to induce arthritis in B6N mice. An immunodominant COMP peptide was identified as the key T cell epitope, with a perfect fit into the Ab class II peptide binding pocket. A critical amino acid in this peptide was found to be phenylalanine at position 95. Recombinant COMP mutated at position 95 (COMP_F95S) lost its ability to induce arthritis or a strong immune response in the B6N mice. In conclusion, A new model for RA has been established using C57BL/6 mice through immunization with COMP, which is dependent on a COMP specific peptide binding Ab, thus in similarity with CIA in Aq expressing strains.


Assuntos
Artrite Experimental/imunologia , Artrite Experimental/fisiopatologia , Proteína de Matriz Oligomérica de Cartilagem/administração & dosagem , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Animais , Proteína de Matriz Oligomérica de Cartilagem/imunologia , Epitopos de Linfócito T/imunologia , Genes MHC da Classe II , Injeções Intradérmicas , Masculino , Camundongos , Peptídeos/administração & dosagem , Peptídeos/síntese química
6.
Front Immunol ; 8: 698, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28674533

RESUMO

The IL-17-producing CD4+ T helper cell (Th17) differentiation is affected by stimulation of the aryl hydrocarbon receptor (AhR) pathway and by hypoxia-inducible factor 1 alpha (HIF-1α). In some cases, Th17 become non-pathogenic and produce IL-10. However, the initiating events triggering this phenotype are yet to be fully understood. Here, we show that such cells may be differentiated at low oxygen and regardless of AhR ligand treatment such as cigarette smoke extract. Hypoxia led to marked alterations of the transcriptome of IL-10-producing Th17 cells affecting genes involved in metabolic, anti-apoptotic, cell cycle, and T cell functional pathways. Moreover, we show that oxygen regulates the expression of CD52, which is a cell surface protein that has been shown to suppress the activation of other T cells upon release. Taken together, these findings suggest a novel ability for Th17 cells to regulate immune responses in vivo in an oxygen-dependent fashion.

7.
PLoS One ; 11(7): e0160291, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27467144

RESUMO

Immune responses often take place where nutrients and O2 availability are limited. This has an impact on T cell metabolism and influences activation and effector functions. T cell proliferation and expansion are associated with increased consumption of glutamine which is needed in a number of metabolic pathways and regulate various physiological processes. The first step in endogenous glutamine metabolism is reversible and is regulated by glutaminase (GLS1 and GLS2) and glutamine synthase (GLUL). There are two isoforms of GLS1, Kidney type glutaminase (KGA) and Glutaminase C (GAC). The aim of this study is to investigate the expression, localization and role of GLS1 and GLUL in naïve and activated human CD4+ T cells stimulated through the CD3 and CD28 receptors under normoxia and hypoxia. In proliferating cells, GAC was upregulated and KGA was downregulated, and both enzymes were located to the mitochondria irrespective of O2 levels. By contrast GLUL is localized to the cytoplasm and was upregulated under hypoxia. Proliferation was dependent on glutamine consumption, as glutamine deprivation and GLS1 inhibition decreased proliferation and expression of CD25 and CD226, regardless of O2 availability. Again irrespective of O2, GLS1 inhibition decreased the proportion of CCR6 and CXCR3 expressing CD4+ T cells as well as cytokine production. We propose that systemic Th cell activation and expansion might be dependent on glutamine but not O2 availability.


Assuntos
Glutaminase/antagonistas & inibidores , Ativação Linfocitária , Oxigênio/metabolismo , Linfócitos T Auxiliares-Indutores/enzimologia , Antígenos CD/metabolismo , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Glutamina/administração & dosagem , Humanos , Mitocôndrias/enzimologia , Receptores de Quimiocinas/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo
8.
Cardiovasc J Afr ; 25(3): 124-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25000442

RESUMO

OBJECTIVE: Buerger's disease and atherosclerosis obliterans (ASO) are two peripheral arterial diseases (PAD) that are frequently encountered. The aim of this study was to compare quality of life (QOL) in patients with Buerger's disease and ASO. METHODS: We prospectively followed 86 patients who were admitted to our hospital due to ASO or Buerger's disease. Their ischaemia was evaluated according to the clinical category chronic limb ischaemia at the time of hospital admission and at six and 12 months. The QOL was measured at the time of hospital admission and at six and 12 months with the Short Form Health Status Survey (SF-36) and Vascular Quality of Life Questionnaire (VASCUQOL). RESULTS: A total of 86 patients with ASO or Buerger's disease (47 and 39, respectively) were included in the study. Pain parameters from both SF-36 and VASCUQOL scores were lower in patients with Buerger's disease at the time of hospital admission and at six months. The impairment in QOL was found to be proportional to the extent of chronic limb ischaemia. Conversely, when patients with critical limb ischaemia were evaluated, no difference was observed between those with ASO or Buerger's disease in terms of QOL. Amputations were found to have a negative effect on quality of life. CONCLUSION: Buerger's disease had a more pronounced negative effect on QOL than ASO, particularly in terms of pain score. When critical limb ischaemia was considered, ASO and Buerger's disease impaired quality of life at the same rate.


Assuntos
Aterosclerose/complicações , Doenças Vasculares Periféricas/fisiopatologia , Qualidade de Vida , Tromboangiite Obliterante/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/efeitos adversos , Aterosclerose/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/etiologia , Doenças Vasculares Periféricas/cirurgia
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