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1.
Molecules ; 26(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071080

RESUMO

The main purpose of this study was to investigate whether the blockade of the interaction between the receptor activator of nuclear factor-κB (NF-ĸB) ligand (RANKL) and its receptor RANK as well as the blockade of NF-κB inhibitor kinase (IKK) and of NF-κB translocation have the potential to suppress the pathogenesis of allergic asthma by inhibition and/or enhancement of the production by CD4+ and CD8+ T cells of important cytokines promoting (i.e., IL-4 and IL-17) and/or inhibiting (i.e., IL-10 and TGF-ß), respectively, the development of allergic asthma. Studies using ovalbumin(OVA)-immunized mice have demonstrated that all the tested therapeutic strategies prevented the OVA-induced increase in the absolute number of IL-4- and IL-17-producing CD4+ T cells (i.e., Th2 and Th17 cells, respectively) indirectly, i.e., through the inhibition of the clonal expansion of these cells in the mediastinal lymph nodes. Additionally, the blockade of NF-κB translocation and RANKL/RANK interaction, but not IKK, prevented the OVA-induced increase in the percentage of IL-4-, IL-10- and IL-17-producing CD4+ T cells. These latter results strongly suggest that both therapeutic strategies can directly decrease IL-4 and IL-17 production by Th2 and Th17 cells, respectively. This action may constitute an important mechanism underlying the anti-asthmatic effect induced by the blockade of NF-κB translocation and of RANKL/RANK interaction. Thus, in this context, both these therapeutic strategies seem to have an advantage over the blockade of IKK. None of the tested therapeutic strategies increased both the absolute number and frequency of IL-10- and TGF-ß-producing Treg cells, and hence they lacked the potential to inhibit the development of the disease via this mechanism.


Assuntos
Asma/imunologia , Asma/metabolismo , Animais , Asma/fisiopatologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Hipersensibilidade/fisiopatologia , Imunoglobulina E/imunologia , Interleucina-17/imunologia , Interleucina-4/imunologia , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Células Th17/efeitos dos fármacos , Células Th2/efeitos dos fármacos
2.
Molecules ; 26(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34577127

RESUMO

The purpose of the present study was to broaden the knowledge and understanding of the effects of oclacitinib (OCL), a Janus kinase inhibitor, on T cells in the context of both the immune mechanisms underlying anti-inflammatory and anti-allergic properties of the drug and its safety. The results indicate that beneficial effects of OCL in the treatment of skin allergic diseases may be partially mediated by the inhibition of IL-4 production in CD4+ and CD8+ T cells. To a certain extent, the antiproliferative effect of OCL on CD8+ T cells may also contribute to its therapeutic effect. The study found that OCL does not affect the proliferation of CD4+ T cells or the number of IFN-γ- and IL-17-producing CD4+ and CD8+ T cells. Moreover, OCL was found to counteract the induction of type 1 regulatory T (Tr1) cells and to act as a strong inhibitor of IL-10 production in both CD4+ and CD8+ T cells. Thus, these results indicate that beneficial effects of OCL in the treatment of skin allergic diseases are not mediated through: (a) the abolishment of IFN-γ and IL-17-production in CD4+ and CD8+ T cells; (b) generation of Tr1 cells; (c) inhibition of CD4+ T cell proliferation; (d) induction of IL-10 production in CD4+ T cells. The results of this study strongly suggest that, with respect to the evaluated parameters, OCL exerts a suppressive effect on Th2- but not Th1-mediated immunity.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Interleucina-10 , Pirimidinas , Sulfonamidas , Animais , Interleucina-4 , Inibidores de Janus Quinases , Camundongos , Células Th2
3.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361734

RESUMO

Traditional wastewater purification processes are based on a combination of physical, chemical, and biological methods; however, typical electrochemical techniques for removing pollutants require large amounts of electrical energy. In this study, we report on a process of wastewater purification, through continuous anodic dissolution of iron anode for aerated Cu/Fe galvanic cell in synthetic Na2SO4 wastewater solution. Electrochemical experiments were conducted by means of a laboratory size electrolyzer, where electrocoagulation along with electrooxidation phenomena were examined for wastewater containing Acid Mixture dye. The above was visualized through the employment of electrochemical (cyclic voltammetry and ac impedance spectroscopy techniques) along with instrumental spectroscopy analyses.

4.
Toxicol Ind Health ; 32(12): 1961-1970, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26381690

RESUMO

The negative health effects caused by lead (Pb) exposure are widely recognized; however, the molecular mechanisms remain unknown. The aim of this study was to assess the effect of occupational Pb exposure on telomere length and to investigate the potential mechanisms leading to telomere shortening. A cohort of 334 male Pb smelters (exposed group) and 60 age-adjusted males unexposed to Pb (control group) were examined. Assessments of relative telomere length (rTL) and telomerase reverse transcriptase (TERT) gene expression were performed using quantitative real-time polymerase chain reactions. Assessments of whole blood Pb (B-Pb) and whole blood cadmium (B-Cd) concentrations and serum selenium concentration (S-Se) were performed using graphite furnace atomic absorption spectrometry. We analyzed total oxidation status (TOS), lipid hydroperoxides (LHPs), malonylodialdehyde levels in serum (MDA) and in erythrocyte hemolysates (MDA-hgb), and 8-hydroxy-deoxy-guanosine (8-OHdG). The Pb-exposed group had higher B-Pb values and shorter rTL than the control group. The arithmetic mean values calculated for B-Pb were 33 µg/dL versus 2.2 µg/dL (p < 0.0001), and the rTL values were 0.928 and 1.126 relative units (p = 0.001), respectively, for the Pb-exposed and control groups. The rTL was found to gradually shorten in response to the increasing levels of Pb exposure. The Pb-exposed group also demonstrated a higher level of oxidative stress than the control group, which was indicated by increased TOS and MDA-hgb values. rTL was negatively associated with parameters that indicated increased oxidative stress, including TOS (Spearman's rank coefficient (rS) = -0.16; p < 0.01) and MDA-hgb (rS = -0.17; p < 0.001). No correlations were found between rTL and B-Cd and S-Se or smoking and MDA and LHP levels. Univariate analysis indicated that B-Pb was associated with decreased rTL (ß =-0.0041; p = 0.0063) and that the association between B-Pb and rTL remained significant, even when adjusting for age (ß = -0.0041; p = 0.0065) and in multivariable-adjusted model (ß = -0.0042; p = 0.0063). In conclusion, occupational Pb exposure resulted in decreased rTL and may represent a mechanism that contributes to Pb-related diseases.


Assuntos
Chumbo/toxicidade , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/genética , Telomerase/metabolismo , Telômero/ultraestrutura , 8-Hidroxi-2'-Desoxiguanosina , Cádmio/sangue , Cádmio/toxicidade , Estudos de Casos e Controles , Estudos de Coortes , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Humanos , Chumbo/sangue , Peróxidos Lipídicos/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Selênio/sangue , Espectrofotometria Atômica , Telomerase/genética
5.
Waste Manag ; 138: 274-284, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34920243

RESUMO

Waste pollution is one of the most significant environmental issues in the modern world. The importance of recycling is well known, both for economic and ecological reasons, and the industry demands high efficiency. Current studies towards automatic waste detection are hardly comparable due to the lack of benchmarks and widely accepted standards regarding the used metrics and data. Those problems are addressed in this article by providing a critical analysis of over ten existing waste datasets and a brief but constructive review of the existing Deep Learning-based waste detection approaches. This article collects and summarizes previous studies and provides the results of authors' experiments on the presented datasets, all intended to create a first replicable baseline for litter detection. Moreover, new benchmark datasets detect-waste and classify-waste are proposed that are merged collections from the above-mentioned open-source datasets with unified annotations covering all possible waste categories: bio, glass, metal and plastic, non-recyclable, other, paper, and unknown. Finally, a two-stage detector for litter localization and classification is presented. EfficientDet-D2 is used to localize litter, and EfficientNet-B2 to classify the detected waste into seven categories. The classifier is trained in a semi-supervised fashion making the use of unlabeled images. The proposed approach achieves up to 70% of average precision in waste detection and around 75% of classification accuracy on the test dataset. The code and annotations used in the studies are publicly available online1.


Assuntos
Aprendizado Profundo , Benchmarking , Plásticos
6.
Res Vet Sci ; 132: 17-27, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32474261

RESUMO

Teriflunomide (TER) is an immunomodulatory agent. Although the first reports on the use of TER in dogs have already appeared, immune mechanisms underlying the immunomodulatory effect of TER do not seem to have been fully elucidated yet. There were two aspects of this study. First, further insight into the mode of action of TER was gained by investigating its effect on the expression of IL-2 receptor α-chain (CD25) and Forkhead box P3 (Foxp3) by CD4+ and CD8+ T cells and apoptosis of these cells. Second, in view in the earlier lack of data on the effect of TER on T cells in dogs, the results of this study filled in this gap. TER at a concentration which can be achieved in vivo prevented or reduced the activation-induced CD25 expression on CD4+ and CD8+ T cells, respectively. Taking into consideration the role of CD25 in T cell proliferation, this effect may constitute an additional mechanism responsible for the antiproliferative effect of the drug. Under stimulation conditions, TER induced Foxp3 expression in Foxp3-negative CD4+ and CD8+ T cells, while down-regulating it under unstimulated conditions. These results suggest that TER may generate iTreg cells, but this process requires cell activation. TER was not found to affect on the absolute count and apoptosis of CD4+ and CD8+ T cells. The results suggest that the impairment of CD25 expression during T cell activation and generation of iTreg cells may constitute additional mechanisms, besides the principal one, underlying the immunomodulatory effect of TER.


Assuntos
Apoptose , Crotonatos/farmacologia , Cães/imunologia , Fatores de Transcrição Forkhead/metabolismo , Fatores Imunológicos/farmacologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Linfócitos T Reguladores/imunologia , Toluidinas/farmacologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Hidroxibutiratos , Nitrilas , Linfócitos T Reguladores/metabolismo
7.
Poult Sci ; 99(10): 4750-4757, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988509

RESUMO

Tetracyclines continue to be important antimicrobials in veterinary medicine. However, the pharmacokinetics (PK) of tigecycline (TIG) and minocycline (MIN) in broiler chickens has not been investigated to date, and the PK of chlortetracycline (CTC) and tetracycline (TET) remains insufficiently researched, especially in terms of absorption. These antimicrobials have never been compared in a single setting in a single species; therefore, the aim of the present study was to compare the PK of TIG, MIN, CTC, and TET in broiler chickens. Each drug (10 mg/kg) was administered intravenously (IV) and orally (PO). The plasma concentrations of each drug were determined by liquid chromatography-tandem mass spectrometry, and the results were analyzed using compartmental and non-compartmental PK models. Despite the fact that all of the studied antimicrobials were administered at an identical IV dose, the area under the concentration-time curve between zero and the last sampling point (AUC0→t) for MIN (35,014 ± 3,274 µg × hour/mL) and CTC (41,851 ± 10,965 µg × hour/mL) differed significantly from that determined for TIG (18,866 ± 4,326 µg × hour/mL) and TET (17,817 ± 4,469 µg × hour/mL). After IV administration, the values of AUC0→t were also directly related to total body clearance values which were significantly higher for TIG (0.56 ± 0.14 L/hour × kg) and TET (0.60 ± 0.14 L/hour × kg) than for CTC (0.25 ± 0.05 L/hour × kg) and MIN (0.29 ± 0.03 L/hour × kg). In turn, after PO administration, TIG was absorbed in only 1.55% ± 0.82, and CTC in 30.54% ± 6.99, whereas the bioavailability of MIN and TET was relatively high at 52.33% ± 3.92 and 56.45% ± 9.71, respectively. The differences in PK parameters between these drugs, despite their structural similarities, suggest that active transport mechanisms may play a role in their absorption and distribution.


Assuntos
Galinhas , Clortetraciclina , Minociclina , Tetraciclina , Tigeciclina , Animais , Antibacterianos/farmacocinética , Área Sob a Curva , Clortetraciclina/farmacocinética , Vias de Eliminação de Fármacos , Minociclina/farmacocinética , Tetraciclina/farmacocinética , Tigeciclina/farmacocinética
8.
Res Vet Sci ; 121: 124-129, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30391724

RESUMO

Oclacitinib (OCL) is a novel immunosuppressive agent approved for dogs that controls itch and inflammation in allergic disease via the inhibition of the JAK/STAT pathway. This paper investigates the in vitro effect of OCL, a novel Janus kinase inhibitor, on selected canine regulatory (Treg) and effector (Teff) CD4+ and CD8+ T cells. Exposure of peripheral blood lymphocytes to OCL did not affect the transcription factor Foxp3 (Forkhead Box P3 protein) expression in CD25+CD4+ and CD25+CD8+ T cells. Moreover, OCL did not influence constitutive CD25 expression on these cells although it reduced the activation-induced CD25 expression on CD4+ T cells. Unexpectedly, the research demonstrated the cytoreductive and proapoptotic effects of OCL on the cells examined. Exposure to OCL caused a dramatic loss of both CD4+ and CD8+ T cells and this effect was observed in both Treg and Teff cell subsets. On the one hand, cytoreductive and proapoptotic effects of OCL toward CD4+ and CD8+ Teff cells, as well as the drug-induced inhibition of CD4+ T cell activation, may be considered as additional mechanisms involved in producing anti-inflammatory and anti-allergic properties of the drug. On the other hand, these effects also represent the immunosuppressive action in the sense of an unwanted effect because CD4+ and CD8+ Teff cells play a crucial role in the production of cellular immunity. Further studies are needed to determine whether the use of OCL actually creates the risk of such action.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunossupressores/farmacologia , Janus Quinase 1/antagonistas & inibidores , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Animais , Cães
9.
Biol Trace Elem Res ; 170(1): 1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26179085

RESUMO

The possible beneficial role of selenium (Se) on the oxidative stress induced by lead (Pb) is still unclear in humans. Therefore, the aim of the present study was to explore the associations among the Se levels, chronic Pb exposure, oxidative stress parameters, and parameters characterizing the function of the antioxidant defense system in men who are occupationally exposed to Pb. Based on the median serum Se concentrations, the 324 study subjects were divided into two subgroups: a subgroup with a low Se level (L-Se) and a subgroup with a high Se level (H-Se). The levels of lead (PbB) and zinc protoporphyrin (ZPP) in the blood and the delta-aminolevulinic acid (ALA) level in the urine served as indices of Pb exposure. The PbB level was significantly lower in the H-Se group compared to that in the L-Se group by 6 %. The levels of 8-hydroxyguanosine and lipofuscin (LPS) and the activity of superoxide dismutase were significantly lower in the H-Se group compared to that in the L-Se group by 17, 19, and 11 %, respectively. However, the glutathione level (GSH) and the activities of glutathione peroxidase (GPx) and catalase were significantly higher by 9, 23, and 3 %. Spearman correlations showed positive associations between the Se level and GPx activity and GSH level. A lower serum Se level in chronically Pb-exposed subjects is associated with higher Pb blood levels and an elevated erythrocyte LPS level, which reflects the intensity of oxidative stress. Besides, in a group of Pb-exposed subjects with lower serum Se level, depleted GSH pool and decreased activity of GPx in erythrocytes were reported. However, the present results are inadequate to recommend Se supplementation for chronic lead exposure at higher doses than would be included in a normal diet except for selenium deficiency.


Assuntos
Chumbo/toxicidade , Exposição Ocupacional , Estresse Oxidativo , Selênio/sangue , Adulto , Humanos , Chumbo/sangue , Masculino , Pessoa de Meia-Idade
10.
Environ Toxicol Pharmacol ; 45: 235-40, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27331344

RESUMO

The aim of the study was to investigate the influence of subacute exposure to lead on the glutathione-related antioxidant defense and oxidative stress parameters in 36 males occupationally exposed to lead for 40±3.2days. Blood lead level in the examined population increased significantly by 359% due to lead exposure. Simultaneously, erythrocyte glutathione level decreased by 16%, whereas the activity of glutathione-6-phosphate dehydrogenase in erythrocytes and leukocytes decreased by 28% and 10%, respectively. Similarly, the activity of glutathione-S-transferase in erythrocytes decreased by 45%. However, the activity of glutathione reductase in erythrocytes and leukocytes increased by 26% and 6%, respectively, whereas the total oxidant status value in leukocytes increased by 37%. Subacute exposure to lead results in glutathione pool depletion and accumulation of lipid peroxidation products; however, it does not cause DNA damage. Besides, subacute exposure to lead modifies the activity of glutathione-related enzymes.


Assuntos
Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Glutationa/metabolismo , Chumbo/toxicidade , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Adulto , Antioxidantes/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/metabolismo , Humanos , Chumbo/sangue , Leucócitos/efeitos dos fármacos , Leucócitos/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Polônia , Fatores de Tempo , Adulto Jovem
11.
PLoS One ; 9(1): e87337, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24475276

RESUMO

The sensitivity of different plant species to mutagenic agents is related to the DNA content and organization of the chromatin, which have been described in ABCW and bodyguard hypotheses, respectively. Plant species that have B chromosomes are good models for the study of these hypotheses. This study presents an analysis of the correlation between the occurrence of B chromosomes and the DNA damage that is induced by the chemical mutagen, maleic hydrazide (MH), in Crepis capillaris plants using comet assay. The presence of B chromosomes has a detectable impact on the level of DNA damage. The level of DNA damage after MH treatment was correlated with the number of B chromosomes and it was observed that it increased significantly in plants with 3B chromosomes. We did not find evidence of the protective role from chemical mutagens of the constitutive heterochromatin for euchromatin in relation to DNA damage. The DNA damage involving the 25S rDNA sequences was analyzed using the comet-FISH technique. Fragmentation within or near the 25S rDNA involved the loci on the A and B chromosomes. The presence of B chromosomes in C. capillaris cells had an influence on the level of DNA damage that involves the 25S rDNA region.


Assuntos
Cromossomos de Plantas/genética , Crepis/genética , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Ensaio Cometa , Hibridização in Situ Fluorescente , Hidrazida Maleica/toxicidade , RNA Ribossômico/genética
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