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Immunologic contact urticaria (ICU) is characterized by the wheal and flare reaction from direct contact with a chemical or protein agent, which involves a type I hypersensitivity mediated by allergen-specific immunoglobulin E (sIgE). Myricetin (Myr), a bioactive flavonoid, exhibits antiinflammatory activities. Our results showed that treatment with Myr could alleviate ICU symptoms, including a decrease in the number of wheals and scratching, and inhibit ear swelling in the IgE/DNFB-induced mice. The serum level of IgE, histamine, interleukin (IL)-4, TNF-α, and MCP-1 were reduced in Myr-treated mice. Myr also attenuated mast cells (MCs) degranulation and H-PGDS, TSLP, IL-33, PI3K, Akt, and NF-κB mRNA levels in ICU model. The IgE-mediated anaphylaxis mouse models demonstrated anti-allergic effects of Myr. In vitro analysis showed that Myr reduced IgE-induced calcium (Ca2+ ) influx, suppressed degranulation, and chemokine release in LAD2 cells (human primary mast cells). Myr can significantly inhibited PLCγ1, Akt, NF-κB, and p38 phosphorylation. In conclusion, the study demonstrated that Myr alleviate ICU symptoms and inhibit mast cell activation via PI3K/Akt/NF-κB signal pathway.
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NF-kappa B , Urticária , Humanos , Animais , Camundongos , Mastócitos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Degranulação Celular , Urticária/tratamento farmacológico , Flavonoides/farmacologiaRESUMO
OBJECTIVE: To evaluate the mechanism of Bone Marrow Mesenchymal Stem Cells (BMSCs) in regulating NF-κB signal pathway by targeting miR-449a. METHODS: Stem cells were transfected by over-expressing and inhibiting miR-449a to detect the levels and viability of miR-449a in stem cells after transfection. Stem cells and neurons were co-cultured in vitro to evaluate the in vitro mechanism of stem cells over-expressing miR-449a on neurons. RESULTS: After the addition of neurons, the neuronal activity of miR-449a over-expression group increased significantly, the expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, and the inflammatory cytokines (TNF-α and IL-1ß) decreased significantly (P<0.05). In vivo experiments in rats also showed that rats were unresponsive, did not chirp or elude after being stimulated. After stem cell therapy, the weight and response of rats gradually returned to normal levels. miR-449a expression significantly increased in the stem cell + miR-449a over-expression group, expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, inflammatory cytokines (TNF-α and IL-1ß) significantly decreased, and cell activity significantly increased (P<0.05). CONCLUSIONS: BMSCs can modulate NF-κB signaling pathway by targeting miR-449a, so as to reduce the inflammatory response to peripheral nerve injury and repair nerve injury.
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Células-Tronco Mesenquimais , MicroRNAs , Traumatismos dos Nervos Periféricos , Animais , Ratos , Citocinas , MicroRNAs/genética , NF-kappa B , Inibidor de NF-kappaB alfa , Transdução de Sinais , Fator de Necrose Tumoral alfaRESUMO
BACKGROUND: Femoral artery puncture is still the most used surgical approach. Because the operation requires local anaesthesia, the patient may not be able to exert full self-control, and their upper and lower limbs and trunk need to be constrained by a protection device. OBJECTIVE: To explore the safe application effect of a new type of anti-movement protection device for upper and lower extremities, shoulders and chest in patients undergoing interventional therapy via the femoral artery approach. METHODS: This is a prospective randomised controlled study. A total of 230 patients were randomly divided into two groups: the study group (n= 115) and the control group (n= 115). The time needed to implement the restraint operation and the loosening of the restraint device in the two groups was recorded, and the satisfaction of surgeons and nurses was investigated. RESULTS: The time needed to perform restraint operation in the study group was significantly less than that in the control group (4.06 ± 0.61 min vs. 7.01 ± 0.76 min, P< 0.05). The satisfaction of surgeons and nurses with the use of the new protective device was significantly better than that of the conventional restraint band (P< 0.05). CONCLUSION: The new anti-movement protection device for upper and lower limbs, shoulders and chest can conveniently and quickly achieve effective protection and braking of patients, ensure the safety of surgery and improve satisfaction.
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Artéria Femoral , Equipamentos de Proteção , Humanos , Artéria Femoral/cirurgia , Estudos Prospectivos , Projetos de Pesquisa , Extremidade Inferior , Resultado do TratamentoRESUMO
The composting of sewage sludge and maize straw was investigated in forced-aeration composting systems at initial C/N ratios of 14, 20, and 25, respectively. The temperatures of composting mixture with initial C/N ratios of 25 and 20 could meet the requirement of destroying pathogens. The final electrical conductivity (EC) of composting mixture with initial C/N ratios of 20 and 25 did not exceed the limit value of 3000 microS cm(-1), and the NH4(+)-N content of composting mixture with an initial C/N ratio of 14 did not meet the limit value of 400 mg kg(-1). The final NO3(-)-N and germination index (GI) of composting mixture with an initial C/N ratio of 25 were higher than those of composting mixtures with initial C/N ratios of 14 and 20. The Fourier transform infrared (FTIR) spectra of composting mixtures in the three composting mixtures showed the same changing pattern during the composting.
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Carbono , Nitrogênio , Caules de Planta , Esgotos/química , Zea mays , Amônia , Reatores Biológicos , Nitratos , Fatores de TempoRESUMO
BACKGROUND: Triple-negative breast cancer (TNBC) has the poorest prognosis among all breast cancer subtypes. While several tumor types are excepted to have a curative response to immunotherapy through the AT-rich interaction domain 1A (ARID1A) gene, its role in TNBC remains unclear. METHODS: The expression of the ARID1A gene and immune infiltration in TNBC were analyzed by way and function enrichment analysis. Additionally, 27 gene mutations, including ARID1A mutation, were detected in paraffin-embedded TNBC specimens and normal breast specimens using Next Generation Sequencing (NGS). Immunohistochemical staining was employed to detect the expression of AIRD1A, TP53, Ki67, CD4, CD8, and PD-L1 proteins in TNBC and the adjacent normal tissue samples. RESULTS: The bioinformatics analysis revealed that ARID1A was mutated in TNBC and significantly associated with tumor immune infiltration. NGS analysis showed a high mutation rate of ARID1A (35%) in TNBC, but the mutation status of ARID1A was not associated with age at onset, lymph node metastasis, pathological grade, or Ki67 index. Low expression or loss of AIRD1A was more commonly observed in TNBC tissues (36/108) as compared to normal tissues (3/25). Positive expression of CD8 and PD-L1 was observed in TNBC tissues with low ARID1A expression. ARID1A mutation was associated with low protein expression, and patients with ARID1A mutation or low protein expression had shorter progression-free survival. CONCLUSION: The ARID1A mutation and low expression are associated with poor prognosis and high immune infiltration in TNBC, and might be biomarkers for TNBC prognosis and immunotherapy efficacy.
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Nonmutational mechanisms were recently discovered leading to reversible drug tolerance. Despite the rapid elimination of a majority of tumor cells, a small subpopulation of "'drug-tolerant"' cells remain viable with lethal drug exposure, which may further lead to resistance or tumor relapse. Several signaling pathways are involved in the local or systemic inflammatory responses contributing to drug-induced phenotypic switch. Here, we report that Toll-like receptor 4 (TLR4)-interacting lipid docosahexaenoic acid (DHA) restores the cytotoxic effect of doxorubicin (DOX) in the lipopolysaccharide-treated breast tumor cell line 4T1, preventing the phenotypic switch to drug-tolerant cells, which significantly reduces primary tumor growth and lung metastasis in both 4T1 orthotopic and experimental metastasis models. Importantly, DHA in combination with DOX delays and inhibits tumor recurrence following surgical removal of the primary tumor. Furthermore, the coencapsulation of DHA and DOX in a nanoemulsion significantly prolongs the survival of mice in the postsurgical 4T1 tumor relapse model with significantly reduced systemic toxicity. The synergistic antitumor, antimetastasis, and antirecurrence effects of DHA + DOX combination are likely mediated by attenuating TLR4 activation, thus sensitizing tumor cells to standard chemotherapy.
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AIM: Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a potent and selective inhibitor of 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) with the ability to ameliorate metabolic disorders in diet-induced obese mice. In the present study, we investigated the effects of emodin on adipocyte function and the underlying mechanisms in vitro, and its anti-diabetic effects in ob/ob mice. METHODS: 3T3-L1 adipocytes were used for in vitro studies. 11ß-HSD1A activity was evaluated with a scintillation proximity assay. The adipogenesis, glucose uptake, lipolysis and adiponectin secretion were investigated in 3T3-L1 adipocytes treated with emodin in the presence of active (corticosterone) or inactive glucocorticoid (11-dehydrocorticosterone). For in vivo studies, ob/ob mice were administered emodin (25 and 50 mg·kg⻹·d⻹, ip) for 26 d. On the last day of administration, the serum was collected and the mesenteric and perirenal fat were dissected for analyses. RESULTS: Emodin inhibited the 11ß-HSD1 activity in 3T3-L1 adipocytes in concentration- and time-dependent manners (the IC50 values were 7.237 and 4.204 µmol/L, respectively, after 1 and 24 h treatment. In 3T3-L1 adipocytes, emodin (30 µmol/L) suppressed 11-dehydrocorticosterone-induced adipogenesis without affecting corticosterone-induced adipogenesis; emodin (3 µmol/L) reduced 11-dehydrocorticosterone-stimulated lipolysis, but had no effect on corticosterone-induced lipolysis. Moreover, emodin (3 µmol/L) partly reversed the impaired insulin-stimulated glucose uptake and adiponectin secretion induced by 11-dehydrocorticosterone but not those induced by corticosterone. In ob/ob mice, long-term emodin administration decreased 11ß-HSD1 activity in mesenteric adipose tissues, lowered non-fasting and fasting blood glucose levels, and improved glucose tolerance. CONCLUSION: Emodin improves the inactive glucocorticoid-induced adipose tissue dysfunction by selective inhibition on 11ß-HSD1 in adipocyte in vitro and improves glycemic control in ob/ob mice.
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11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Adipócitos/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Emodina/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adiponectina/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/patologia , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Relação Dose-Resposta a Droga , Emodina/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Glucocorticoides/toxicidade , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Concentração Inibidora 50 , Insulina/metabolismo , Lipólise/efeitos dos fármacos , Camundongos , Camundongos Obesos , Fatores de TempoRESUMO
Objective: To assess the TNFAIP3 and nuclear factor κB (NFκB) protein expressions in colorectal cancer (CRC) tissue and to analyze the association of these proteins with the clinical pathological characteristics of CRC. Methods: The following methods should be used in clinical trials: information collection and immunohistochemical methods. The following methods are used for cell experiment: cell transfection, CCK8 detection method, transwell experiment, and western blot experiment. Explore the TNFAIP3 expression in CRC cells, and assess the effect of upregulated TNFAIP3 expression on CRC cell proliferation, invasion, and migration. In clinical experiment, we selected the tumor tissues of 39 CRC patients as our experimental samples. We also collected corresponding patient demographics, such as sex, age, cell differentiation, tumor type, and lymph node metastasis. We also analyzed the TNFAIP3 and NFκB protein expressions in 20 experimental and 20 control samples and evaluated potential correlations between these two proteins and clinical pathological characteristics of CRC. For basic experiment, we established CRC cell lines with elevated TNFAIP3 expression and then randomly divided the cells into three groups, namely, TNFAIP3, NS, and Con groups. Using the transwell and CCK8 methods, we detected the CRC migration abilities and cell proliferation, respectively. We also employed western blot analysis to assess protein expression in the three groups. Results: NFκB was highly expressed, and TNFAIP3 was scarcely expressed in the experimental group versus control. The expression of both these proteins were strongly related to the degree of tumor differentiation (P < 0.05). The TNFAIP3 and NFκB protein expressions were significantly associated with lymph node metastasis and tumor differentiation (P < 0.05). For basic experiment, compared to the Con and NS groups, TNFAIP3 protein expression levels, cell proliferation, invasion, and migration were significantly increased in the TNFAIP3 group (P < 0.05). Conclusion: TNFAIP3 overexpression strongly inhibited CRC proliferation, invasion, and migration. Enhanced NFκB protein expression in CRC tissues was associated with elevated malignant degree, metastasis, and TNFAIP3 protein expression in patients who demonstrated high malignant degree and metastasis. Our evidences suggest the promising potential of utilizing TNFAIP3 and NFκB as important reference indices for determining the prognostic outcome of CRC. Furthermore, we revealed that TNFAIP3 overexpression inhibited CRC cell proliferation, invasion, and migration.
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Neoplasias Colorretais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , NF-kappa B , Prognóstico , Proteína 3 Induzida por Fator de Necrose Tumoral alfaRESUMO
BACKGROUND: OSBPL3 is overexpressed in a variety of malignancies and is closely associated with tumor growth and metastasis. However, its expression and function in colorectal cancer (CRC) are unclear. We aimed to investigate its prognostic and therapeutic value in this disease by detecting its expression in CRC and its correlation with the clinicopathological characteristics and prognosis of patients. METHODS: A total of 92 CRC samples were included in this study. According to the 2020 WHO diagnostic criteria, the criteria of the American Joint Committee on Cancer (AJCC) 8th edition staging system were used. OSBPL3 and Ki-67 expression in these samples was detected by immunohistochemistry. OSBPL3 mRNA expression was detected by qRT-PCR. KRAS/NRAS mutations were detected by an amplification refractory mutation system (ARMS). Data analysis was performed using the statistical analysis software Prism 8. RESULTS: OSBPL3 was found to be significantly overexpressed in CRC tumor tissues and was associated with worse progression-free survival and overall survival in patients. Additionally, OSBPL3 expression was negatively correlated with the degree of tumor differentiation. KRAS mutations were detected in approximately 32.6% of patients and were significantly associated with high OSBPL3 expression. In addition, OSBPL3 and Ki-67 expression was significantly correlated. CONCLUSIONS: OSBPL3 is highly expressed in CRC samples and predicts a worse prognosis. OSBPL3 may become a new potential therapeutic target for CRC.
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Neoplasias Colorretais , Antígeno Ki-67 , Proteínas Proto-Oncogênicas B-raf , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas de Ligação a Ácido Graxo/genética , Antígeno Ki-67/genética , Mutação , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genéticaRESUMO
Age-related Macular Degeneration (AMD) is a kind of irreversible vision loss or disease caused by retinal pigment epithelial cells and neuroretinal degeneration, which has become the main cause of vision loss and blindness of the elderly over 65 years old in developed countries. The main clinical manifestations are cognitive decline, mental symptoms and behavioral disorders, and the gradual decline of daily living ability. In this paper, a feature extraction method of electroencephalogram (EEG) signal based on multi-spectral image fusion of multi-brain regions is proposed based on artificial neural network (ANN). In this method, the brain is divided into several different brain regions, and the EEG signals of different brain regions are transformed into several multispectral images by combining with the multispectral image transformation method. Using Alzheimer's disease (AD) classification algorithm, the depth residual network model pre-trained in ImageNet was transferred to sMRI data set for fine adjustment, instead of training a brand-new model from scratch. The results show that the proposed method solves the problem of few available medical image samples and shortens the training time of ANN model.
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Doença de Alzheimer , Degeneração Macular , Idoso , Algoritmos , Doença de Alzheimer/diagnóstico , Encéfalo , Humanos , Degeneração Macular/diagnóstico , Redes Neurais de ComputaçãoRESUMO
Globally, diabetes has assumed epidemic proportions with the neuropathic complications attributed to the malady emerging as a substantial burden on patients and society. DNP has greatly affected the daily life of patients, the effect of traditional treatment methods is not ideal, and it is easy to produce drug resistance. This work is aimed at scrutinizing the effect of upregulating the expression of TNFAIP3 on diabetic neuralgia in mice. This work entailed ascertaining the effects of TNFAIP3 on a murine DNP system. This inspired us to observe the analgesic effect via high expression of lentivirus-mediated TNFAIP3 by intrathecal injection in the animal model to explore its regulatory impacts, symptom relief, and mechanistic role in pain. The results displayed an attenuation of hind paw pain hypersensitivity by LV-TNFAIP3 in the animals. The spinal cord and dorsal root ganglion of mice with neuropathic pain displayed an evident dip in TNFAIP3. Inhibition of the ERK/NF-κB signaling pathway employing LV-TNFAIP3 conspicuously suppressed this pathway while the diabetic pain hypersensitivity was quelled. This effect was also seen with insulin treatment evidently. In conclusion, according to the above analyses, the interaction between DNP and extracellular signal-regulated kinase signal transduction pathway is one of the key factors of pathogenesis.
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Diabetes Mellitus Experimental/complicações , Neuropatias Diabéticas/prevenção & controle , Lentivirus/genética , Neuralgia/prevenção & controle , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/administração & dosagem , Animais , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/patologia , Regulação da Expressão Gênica , Injeções Espinhais , Camundongos , Camundongos Endogâmicos C57BL , Neuralgia/etiologia , Neuralgia/metabolismo , Neuralgia/patologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genéticaRESUMO
The responses of nitrification and denitrification to the divalent zinc (Zn(II)) and tetracycline (TC) co-selective pressure were evaluated in a sequencing batch reactor (SBR). The removal rates of organics and nitrogen, nitrifying and denitrifying enzymatic activity, and microbial diversity and richness at the Zn(II) and TC co-selective pressure were higher than those at the alone Zn(II) selective pressure, while were lower than those at the individual TC selective pressure. The Zn(II) and TC co-selective pressure induced the TC resistance genes abundance increase and the Zn(II) resistance genes levels decrease, and enhanced bacterial enzymatic modification resistance to TC and bacterial outer membrane resistance to Zn(II). The network analysis showed that the genera Nitrospira and Nitrosomonas of nitrifiers and the genera Ferruginibacter, Dechloromonas, Acidovorax, Rhodobacter, Thauera, Cloacibacterium, Zoogloea and Flavobacterium of denitrifiers were the potential hosts of antibiotics resistance genes (ARGs) and/or heavy metals resistance genes (HMRGs).
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Desnitrificação , Nitrificação , Antibacterianos , Reatores Biológicos , Nitrogênio/análise , Águas Residuárias , ZincoRESUMO
Due to the critical correlation between inflammation and carcinogenesis, a therapeutic candidate with anti-inflammatory activity may find application in cancer therapy. Here, we report the therapeutic efficacy of celastrol as a promising candidate compound for treatment of pancreatic carcinoma via naïve neutrophil membrane-coated poly(ethylene glycol) methyl ether-block-poly(lactic-co-glycolic acid) (PEG-PLGA) nanoparticles. Neutrophil membrane-coated nanoparticles (NNPs) are well demonstrated to overcome the blood pancreas barrier to achieve pancreas-specific drug delivery in vivo. Using tumor-bearing mice xenograft model, NNPs showed selective accumulations at the tumor site following systemic administration as compared to nanoparticles without neutrophil membrane coating. In both orthotopic and ectopic tumor models, celastrol-loaded NNPs demonstrated greatly enhanced tumor inhibition which significantly prolonged the survival of tumor bearing mice and minimizing liver metastases. Overall, these results suggest that celastrol-loaded NNPs represent a viable and effective treatment option for pancreatic carcinoma.
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The effects of divalent copper (Cu(II)) on microbial community, enzymatic activity and functional genes in a sequencing batch reactor (SBR) at tetracycline (TC) stress were investigated. The enzymatic activity and functional genes abundance associated with nitrification and denitrification at a 20 mg L-1 TC stress were higher than those at a mixtures stress of 20 mg L-1 TC and 10 mg L-1 Cu(II), while they were lower than those at a mixtures stress of 20 mg L-1 TC and 40 mg L-1 Cu(II). Compared to lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) production at a 20 mg L-1 TC stress, they were lower at the TC stress with 10 mg L-1 Cu(II), while they were higher at the TC stress with 40 mg L-1 Cu(II). The incremental Cu(II) concentration at a 20 mg L-1 TC stress could not change the result that the sensitivity of denitrifying enzymatic activity to TC was higher than nitrifying enzymatic activity. Compared to the relative abundance of nitrifers and denitrifers at a 20 mg L-1 TC stress, the 10 mg L-1 Cu(II) addition resulted in their increase, while they decreased as the 40 mg L-1 Cu(II) addition. The relative abundance of genera Pseudomonas, Rivibacter and Nitrobacter at the stress of Cu(II) and TC were higher than those at TC stress, suggested they had an ability to resist the stress of Cu(II) and TC.
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Cobre/farmacologia , Desnitrificação , Genes Bacterianos , L-Lactato Desidrogenase/metabolismo , Microbiota , Nitrificação , Tetraciclinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Eliminação de Resíduos LíquidosRESUMO
An extracellular matrix-mimicking hydrogel is developed consisting of a hyaluronan-derived component with anti-inflammatory activity, and a gelatin-derived component offering adhesion sites for cell anchorage. The in situ-forming hyaluronan-gelatin (HA-GEL) hydrogel displays a sponge-like microporous morphology. Also, HA-GEL shows a rapid swelling pattern reaching maximum weight swelling ratio within 10 min, while at the equilibrium state, fully swollen hydrogels display an exceedingly high water content with ≈2000% of the dry gel weight. Under typical 2D cell culture conditions, murine 3T3 fibroblasts adhere to, and proliferate on top of the HA-GEL substrates, which demonstrate that HA-GEL provides a favorable microenvironment for cell survival, adhesion, and proliferation. In vivo healing study further demonstrates HA-GEL as a viable and effective treatment option to improve the healing outcome of full thickness wounds in diabetic mice by effectively depleting the inflammatory chemokine monocyte chemoattractant protein-1 in the wound bed.
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Materiais Biomiméticos/química , Gelatina/química , Ácido Hialurônico/química , Hidrogéis/química , Ferida Cirúrgica/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Animais , Bandagens , Materiais Biomiméticos/farmacologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Matriz Extracelular/química , Gelatina/farmacologia , Expressão Gênica , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Masculino , Metacrilatos/química , Camundongos , Camundongos Endogâmicos ICR , Células NIH 3T3 , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Pele/lesões , Pele/metabolismo , Estreptozocina , Ferida Cirúrgica/metabolismo , Ferida Cirúrgica/patologia , Cicatrização/fisiologiaRESUMO
The long-term effects of combined divalent copper (Cu(II)) and tetracycline (TC) on the performance, microbial activity and community in a sequencing batch reactor (SBR) were investigated. The addition of Cu(II), TC or mixed Cu(II)/TC caused the decrease of the organics and nitrogen removal efficiencies, and their decreased degrees were the lowest at the addition of mixed Cu(II)/TC. The increase of mixed Cu(II)/TC concentrations in the influent did not change the antagonistic effects between Cu(II) and TC on nitrifying and denitrifying activities. Nitrifiers had higher tolerances to Cu(II), TC and mixed Cu(II)/TC than denitrifiers. Compared to the addition of Cu(II) or TC alone, the microbial community richness was higher at the addition of mixed Cu(II)/TC, while the microbial community diversity was lower. The increased protein (PN) in extracellular polymeric substances (EPS) was a protective response of bacteria to Cu(II), TC and mixed Cu(II)/TC.