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1.
Mutat Res ; 819-820: 111688, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32014793

RESUMO

Nickel metal is a naturally occurring element used in many industrial and consumer applications. Human epidemiological data and animal cancer bioassays indicate that nickel metal is not likely to be a human carcinogen. Yet, nickel metal is classified as a suspected human carcinogen (CLP) and possibly carcinogenic to humans (IARC). There are no reliable studies on the potential for nickel metal to induce gene and micronucleus (MN) mutations. To fill these datagaps and increase our understanding of the mechanisms underlying the lack of nickel metal carcinogenicity, gene and micronucleus mutation studies were conducted with nickel metal powder (N36F) in V79 Chinese Hamster cells following OECD 476 and 487 guidelines, respectively, under GLP. Gene mutation at the hprt locus was tested, with and without metabolic activation, after 4-h treatment with 0.05-2.5 mM nickel metal powder. Cytokinesis-block MN frequency following exposure to 0.25-1.5 mM nickel metal was tested after 4-h treatment, with and without metabolic activation, followed by a 24-h treatment without metabolic activation. In the gene mutation assay, there were modest increases in hprt mutants observed at some test concentrations, not exceeding 2.2-fold, which were either within the historical control values and/or showed no concentration-response trend. The positive controls showed increases of at least 7-fold. Likewise, no increases in the MN frequency exceeding 1.5-fold were observed with nickel metal, with no concentration-response trends. Taking these results together, it can be concluded that nickel metal is non-mutagenic and does not cause gene nor chromosomal mutations.


Assuntos
Poluentes Ambientais/farmacologia , Hipoxantina Fosforribosiltransferase/genética , Mutação , Níquel/farmacologia , Animais , Células CHO , Aberrações Cromossômicas/efeitos dos fármacos , Cricetulus , Expressão Gênica , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Testes para Micronúcleos , Testes de Mutagenicidade , Pós
2.
Acta Crystallogr C Struct Chem ; 75(Pt 12): 1658-1665, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802756

RESUMO

Because of its versatile coordination modes and strong coordination ability, the mercaptoacetic acid substituted 1,2,4-triazole 2-{[5-(pyridin-2-yl)-4H-1,2,4-triazol-3-yl]sulfanyl}acetic acid (H2L) was synthesized and characterized. Treatment of H2L with cobalt and nickel acetate afforded the dinuclear complexes {µ-3-[(carboxylatomethyl)sulfanyl]-5-(pyridin-2-yl)-4H-1,2,4-triazol-4-ido-κ2N1,N5:N2,O}bis[aqua(methanol-κO)cobalt(II)] methanol disolvate, [Co2(C9H6N4O2S)2(CH3OH)2(H2O)2]·2CH3OH (1), and {µ-3-[(carboxylatomethyl)sulfanyl]-5-(pyridin-2-yl)-4H-1,2,4-triazol-4-ido-κ2N1,N5:N2,O}bis[diaquanickel(II)] methanol disolvate dihydrate, [Ni2(C9H6N4O2S)2(H2O)4]·2CH3OH·2H2O (2), respectively. Complex 1 crystallized in the monoclinic space group P21/c, while 2 crystallized in the tetragonal space group I41/a. Single-crystal X-ray diffraction studies revealed that H2L is doubly deprotonated and acts as a tetradentate bridging ligand in complexes 1 and 2. For both of the obtained complexes, extensive hydrogen-bond interactions contribute to the formation of their three-dimensional supermolecular structures. Hirshfeld surface analysis was used to illustrate the intermolecular interactions. Additionally, the urease inhibitory activities of 1, 2 and H2L were investigated against jack bean urease, where the two complexes revealed strong urease inhibition activities.


Assuntos
Acetatos/química , Cobalto/farmacologia , Complexos de Coordenação/química , Níquel/farmacologia , Compostos Organometálicos/química , Tioglicolatos/farmacologia , Urease/antagonistas & inibidores , Urease/química , Cobalto/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Níquel/química , Tioglicolatos/química
3.
Inorg Chem ; 58(23): 16075-16086, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31729870

RESUMO

GANT61-D is an important hedgehog pathway inhibitor and an interesting ligand candidate for metal coordination. The first examples of metal complexes of the potent hedgehog pathway inhibitor GANT61-D are described. The reaction of Ni(II), Pd(II), and Pt(II) precursors with the hedgehog pathway inhibitor GANT61-D gave [NiII(GANT61-D)(OH2)3(µ2-SO4)(µ3-SO4)] (1), [PdII(Cl)(GANT61-D)]Cl (2), [PtII(Cl)(GANT61-D)]Cl, and [PtII(CBDCA-2H)(GANT61-D)]. X-ray crystal structure analysis revealed that GANT61-D is a versatile N-donor ligand that can act as a bidentate ligand via the diaminopropane (DAP) N atoms or a tridentate ligand via the DAP N atoms and one dimethylaniline N atom. Protonation constants of the GANT61-D ligand in water and in a 60:40 (w/w) dimethyl sulfoxide-water solvent mixture were determined. Potentiometric and spectroscopic data on the NiII(GANT61-D) system indicate the formation of octahedral 1:1 species with medium stability in solution. 1 and 2 exhibited noteworthy in vitro cytotoxicity against medulloblastoma cancer cells.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Níquel/farmacologia , Paládio/farmacologia , Platina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Níquel/química , Paládio/química , Platina/química
4.
Chemosphere ; 237: 124545, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549657

RESUMO

N and P are the key limiting nutrients considered most important for the stimulation of crude oil degradation but other trace nutrients may also be important. Experimental soil microcosms were setup to investigate crude oil degradation in the context of Ni amendments. Amended Nickel as NiO, NiCl2, or, a porphyrin complex either inhibited, had no effect, or, enhanced aerobic hydrocarbon degradation in an oil-contaminated soil. Biodegradation was significantly (95% confidence) enhanced (70%) with low levels of Ni-Porph (12 mg/kg) relative to an oil-only control; whereas, NiO (200 and 350 mg/kg) significantly inhibited (36 and 87%) biodegradation consistent with oxide particle induced reactive oxygen stress. Microbial community compositions were also significantly affected by Ni. In 16S rRNA sequence libraries, the enriched hydrocarbon degrading genus, Rhodococcus, was partially replaced by a Nocardia sp. in the presence of low levels of NiO (12 and 50 mg/kg). In contrast, the highest relative and absolute Rhodococcus abundances were coincident with the maximal rates of oil degradation observed in the Ni-Porph-amended soils. Growth dependent constitutive requirements for Ni-dependent urease or perhaps Ni-dependent superoxide dismutase enzymes (found in Rhodococcus genomes) provided a mechanistic explanation for stimulation. These results suggest biostimulation technologies, in addition to N and P, should also consider trace nutrients such as Ni tacitly considered adequately supplied and available in a typical soil.


Assuntos
Níquel/farmacologia , Petróleo/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Hidrocarbonetos/metabolismo , Microbiota/efeitos dos fármacos , Microbiota/genética , Microbiota/fisiologia , RNA Ribossômico 16S/genética , Rhodococcus/genética , Rhodococcus/metabolismo , Solo/química , Poluentes do Solo/química
5.
Oxid Med Cell Longev ; 2019: 9693726, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316722

RESUMO

Trace metals such as zinc (Zn), copper (Cu), and nickel (Ni) play important roles in various physiological functions such as immunity, cell division, and protein synthesis in a wide variety of species. However, excessive amounts of these trace metals cause disorders in various tissues of the central nervous system, respiratory system, and other vital organs. Our previous analysis focusing on neurotoxicity resulting from interactions between Zn and Cu revealed that Cu2+ markedly enhances Zn2+-induced neuronal cell death by activating oxidative stress and the endoplasmic reticulum (ER) stress response. However, neurotoxicity arising from interactions between zinc and metals other than copper has not been examined. Thus, in the current study, we examined the effect of Ni2+ on Zn2+-induced neurotoxicity. Initially, we found that nontoxic concentrations (0-60 µM) of Ni2+ enhance Zn2+-induced neurotoxicity in an immortalized hypothalamic neuronal cell line (GT1-7) in a dose-dependent manner. Next, we analyzed the mechanism enhancing neuronal cell death, focusing on the ER stress response. Our results revealed that Ni2+ treatment significantly primed the Zn2+-induced ER stress response, especially expression of the CCAAT-enhancer-binding protein homologous protein (CHOP). Finally, we examined the effect of carnosine (an endogenous peptide) on Ni2+/Zn2+-induced neurotoxicity and found that carnosine attenuated Ni2+/Zn2+-induced neuronal cell death and ER stress occurring before cell death. Based on our results, Ni2+ treatment significantly enhances Zn2+-induced neuronal cell death by priming the ER stress response. Thus, compounds that decrease the ER stress response, such as carnosine, may be beneficial for neurological diseases.


Assuntos
Morte Celular/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Níquel/farmacologia , Zinco/farmacologia , Carnosina/farmacologia , Linhagem Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Neurônios/metabolismo
6.
Eur J Med Chem ; 180: 213-223, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31306908

RESUMO

Reactions of Ni(II) and Pd(II) precursors with S-benzyl-N-(ferrocenyl)methylenedithiocarbazate (HFedtc) led to the formation of heterobimetallic complexes of the type [MII(Fedtc)2] (M = Ni and Pd). The characterization of the compounds involved the determination of melting point, FTIR, UV-Vis, 1H NMR, elemental analysis and electrochemical experiments. Furthermore, the crystalline structures of HFedtc and [NiII(Fedtc)2] were determined by single crystal X-ray diffraction. The compounds were evaluated against the intracellular form of Trypanosoma cruzi (Tulahuen Lac-Z strain) and the cytotoxicity assays were assessed using LLC-MK2 cells. The results showed that the coordination of HFedtc to Ni(II) or Pd(II) decreases the in vitro trypanocidal activity while the cytotoxicity against LLC-MK2 cells does not change significantly. [PdII(Fedtc)2] showed the greater potential between the two complexes studied, showing an SI value of 8.9. However, this value is not better than that of the free ligand with an SI of 40, a similar value to that of the standard drug benznidazole (SI = 48). Additionally, molecular docking simulations were performed with Trypanosoma cruzi Old Yellow Enzyme (TcOYE), which predicted that HFedtc binds to the protein, almost parallel to the flavin mononucleotide (FMN) prosthetic group, while the [NiII(Fedtc)2] complex was docked into the enzyme binding site in a significantly different manner. In order to confirm the hypothetical interaction, in vitro experiments of fluorescence quenching and enzymatic activity were performed which indicated that, although HFedtc was not processed by the enzyme, it was able to act as a competitive inhibitor, blocking the hydride transfer from the FMN prosthetic group of the enzyme to the menadione substrate.


Assuntos
Compostos de Benzil/farmacologia , Complexos de Coordenação/farmacologia , Inibidores Enzimáticos/farmacologia , Hidrazinas/farmacologia , Metalocenos/farmacologia , NADPH Desidrogenase/antagonistas & inibidores , Níquel/farmacologia , Paládio/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Humanos , Hidrazinas/química , Macaca mulatta , Metalocenos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , NADPH Desidrogenase/química , NADPH Desidrogenase/metabolismo , Níquel/química , Níquel/metabolismo , Paládio/química , Paládio/metabolismo , Relação Estrutura-Atividade , Tripanossomicidas/química , Tripanossomicidas/metabolismo , Trypanosoma cruzi/metabolismo
7.
Eur J Med Res ; 24(1): 27, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31351486

RESUMO

PURPOSE: To summarize the techniques and clinical effectiveness in treating scaphoid nonunion with nickel-titanium (Ni-Ti) arched shape-memory alloy connector in combination with autologous iliac bone grafts. METHODS: This study retrospectively analyzed 18 scaphoid nonunion cases treated with arched connectors with autologous iliac bone grafts. Based on scaphoid nonunion, 2 cases were classified as type II (fibrous union), 4 cases as type III (mild sclerotic union), 6 cases as type IV (moderate resorption and sclerosis), 5 cases as type V (severe bone resorption and sclerosis), and 1 case as type VI (pseudarthrosis formation). At the first 4, 8 and 12 weeks after the surgery, wrist anteroposterior, lateral X-ray were obtained, respectively, to evaluate bone healing. Patients who had not yet reached the standard of healing at 12 weeks after surgery would continue to receive additional appointments for follow-up visits, such as 14 weeks, 16 weeks, 18 weeks after surgery, until their imaging studies had achieved satisfactory bone healing. Clinical effectiveness was evaluated comprehensively, based on bone union time, Mayo wrist score, and visual analog pain score. RESULTS: All 18 patients achieved satisfactory reduction and fixation with a mean union time of 4.2 months. Preoperative Mayo wrist score averaged 57.4 and average final postoperative follow-up was 91.4. On the other hand, mean preoperative VAS score was 6.8, and final postoperative follow-up average was 1.6. Mayo wrist score of the overall treatment effectiveness was excellent (90-100) in 12 cases, good (80-90) in 5 cases, and acceptable (60-80) in 1 case with zero poor (below 60) cases observed. Statistical analysis suggested that a statistically significant improvement in fracture healing, wrist function recovery and visual analog pain after surgery when compared to the scores of the patients before surgery. CONCLUSION: Using Ni-Ti arched shape-memory alloy connector in combination with autologous bone grafting provided a new modality to treat scaphoid nonunions in a less traumatic, convenient to operate and satisfactory manner in treatment outcomes, and thus is worthy of further application.


Assuntos
Transplante Ósseo , Fraturas não Consolidadas/cirurgia , Níquel/farmacologia , Osso Escafoide/cirurgia , Titânio/farmacologia , Adulto , Fraturas não Consolidadas/fisiopatologia , Humanos , Masculino , Recuperação de Função Fisiológica/efeitos dos fármacos , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/fisiopatologia , Resultado do Tratamento , Punho/fisiopatologia
8.
Chemosphere ; 237: 124428, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31362133

RESUMO

The present study evaluates the enzyme activities and histopathological changes in the post larvae (PL) of shrimp (Penaeus monodon), green mussel (Perna viridis) and fingerlings of crescent perch (Terapon jarbua) exposed to sublethal gradient concentrations of Nickel (Ni). The median lethal concentration (LC50) values were 2.49, 66.03 and 43.92 mg Ni L-1 derived for the PL of shrimp, green mussel and fish fingerlings respectively. No Observed Effect Concentration (NOEC), Lowest Observed Effect Concentration (LOEC) and chronic values of the PL of shrimp were 46.5, 73.0 and 58.3 µg Ni L-1 derived for the 21-d survival endpoint. The NOEC, LOEC and chronic values for the 30-d survival endpoint of the green mussels and fish fingerlings were 4.6, 6.32, 5.4 and 1.95, 2.6, 2.25 mg Ni L-1 respectively. The isoforms of esterase, superoxide dismutase and malate dehydrogenase activities in the whole body tissues of test organisms were studied by native polyacrylamide gel electrophoresis after exposure to Ni. Histological examination of compound eye sections of shrimp revealed deformation, compression, fusion and detachement in the corneal cells from the corneal facet of the ommatidia indicating cellular anomalies due to Ni toxicity. Gill sections of the green mussel witnessed reduced haemolymph in sinuses of gill filaments, degenerative changes in interfilamentous junction and necrosis of frontal ciliated epithelial cells with vacuoles after exposure to Ni. Nickel affects the vision of shrimp and fish fingerlings, gills and byssus of green mussels.


Assuntos
Bivalves/efeitos dos fármacos , Níquel/toxicidade , Penaeidae/efeitos dos fármacos , Percas/crescimento & desenvolvimento , Perna (Organismo)/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Bivalves/enzimologia , Bivalves/crescimento & desenvolvimento , Esterases/química , Olho/efeitos dos fármacos , Olho/patologia , Brânquias/efeitos dos fármacos , Brânquias/patologia , Malato Desidrogenase/química , Níquel/farmacologia , Penaeidae/enzimologia , Penaeidae/crescimento & desenvolvimento , Perna (Organismo)/enzimologia , Perna (Organismo)/crescimento & desenvolvimento , Superóxido Dismutase/química
9.
Afr Health Sci ; 19(1): 1460-1466, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31148973

RESUMO

Background: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD). Objectives: This study was performed to assess nickel induced immune activation among patients sensitized against nickel. Patients and Methods: A total of 35 patients (29 females and 6 males; mean age 36±9 years) with nickel contact dermatitis and 20 patch test negative healthy individuals (14 females and 6 males; mean age 29±7 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-regulation on T lymphocyte sub-sets by flow cytometry. Results: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1±1.3%vs2.8±1.1%;p<0.009). There was no difference in proportions of CD±CD69+ cells between patients and controls (3.2±0.9%vs2.3±0.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lymphocytes (22.1±6.2%) of the ACD patients compared to controls (2.8±2.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2±5.3%) from ACD patients compared to the controls (1.9±1.8%;p<0.0006). Conclusion: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Dermatite Alérgica de Contato/imunologia , Lectinas Tipo C/metabolismo , Níquel/efeitos adversos , Níquel/imunologia , Adulto , Alérgenos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Dermatite Alérgica de Contato/diagnóstico , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Níquel/farmacologia , Testes do Emplastro , Regulação para Cima , Adulto Jovem
10.
Bull Exp Biol Med ; 167(1): 140-144, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31183647

RESUMO

We studied therapeutic activity of co-transplantation of allogeneic pancreatic islet cells and mesenchymal bone marrow progenitors on TiNi scaffolds in Wistar rats with experimental alloxan-induced diabetes mellitus. In preliminary experiments with co-culturing of cells in different proportions followed by their transplantation on tissue-engineered constructs, the optimum ratio of these cells was determined - 3:1. Regeneration was assessed by biochemical methods by the blood levels of glucose and glycosylated hemoglobin on days 15, 30, and 5. In the group with combined cell transplantation on TiNi scaffold, normalization of the studied biochemical parameters occurred earlier than after monotherapy with allogenic islet cells and was associated with an increase in animal lifespan. Normalization of the parameters of bone marrow hemopoiesis, in particular, the number of myelokaryocytes and erythroblasts was also noted.


Assuntos
Aloxano/toxicidade , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Diabetes Mellitus Experimental/terapia , Ilhotas Pancreáticas/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Níquel/farmacologia , Engenharia Tecidual/métodos , Tecidos Suporte/química , Titânio/farmacologia , Animais , Materiais Biocompatíveis/química , Diabetes Mellitus Experimental/induzido quimicamente , Masculino , Níquel/química , Ratos , Ratos Wistar , Titânio/química
11.
Mater Sci Eng C Mater Biol Appl ; 102: 683-695, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31147041

RESUMO

In the present study, the different contents of tantalum pentoxide (Ta2O5: 10, 15, 20 and 30 wt%) nanoparticles were introduced into the natural hydroxyapatite (nHA) coating structure on NiTi substrate through electrophoretic deposition (EPD) method. The phase compositions of coatings were perused before and after the sintering at 800 °C for 1 h by XRD. The incorporation of 30wt%Ta2O5 into nHA matrix induced the formation of undesirable soluble Ca3(PO4)2 phase in composite coating. The FESEM images showed that the density of continuous nHA coating increased by compositing with Ta2O5. The maximum adhesion strength of 28.3 ±â€¯0.7 MPa accomplished from the nHA-20 wt%Ta2O5 composite coating. The Ni ions concentration measurement results from the passivated-NiTi with nHA and nHA-(10, 15 and 20)wt%Ta2O5 coatings during 30 days of immersion in PBS clarified the positive role of Ta2O5 in decreasing the Ni leaching due to the lowering the open porosities of nHA structure. The biological response of the coating surfaces was assessed in vitro by cell culturing and MTS assay. By considering the morphology and density of adsorbed cells on each coating, the improved biocompatibility of nHA coating in the presence of Ta2O5 was justified by scrutinizing the surface roughness, wettability and charge. The highest cell attachment and proliferation on nHA-20 wt%Ta2O5 coating was related to owning the lowest roughness, wetting angle of 34o ±â€¯0.5 and the highest negative surface charge density. Also, the concentration of the highest negative charge density on nHA-20 wt%Ta2O5 coating surface in the SBF solution caused to the enhancement of the amount of the apatite nuclei through providing more sites to calcium absorption.


Assuntos
Ligas/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Elasticidade , Eletroquímica/métodos , Níquel/farmacologia , Osseointegração/efeitos dos fármacos , Óxidos/farmacologia , Tantálio/farmacologia , Titânio/farmacologia , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Íons , Nanopartículas/química , Nanopartículas/ultraestrutura , Níquel/análise , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Propriedades de Superfície , Difração de Raios X
12.
Mater Sci Eng C Mater Biol Appl ; 102: 829-843, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31147055

RESUMO

The synthesis of nickel oxide nanoparticles (NiO NPs) and graphene/nickel oxide nanocomposites (Gr/NiO NCs) was performed using a simple chemical reduction method. Powder X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to examine the crystalline nature and thermal stability of the synthesized NiO NPs and Gr/NiO NCs, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to observe the morphology of NiO NPs and Gr/NiO NCs and estimate their size range. TEM suggested that the NiO NPs were speared onto the surface of Gr nanosheet. The efficiency of NiO NPs and Gr/NiO NCs against extended spectrum ß-lacamase (ESBL) producing bacteria, which was confirmed by specific HEXA disc Hexa G-minus 24 (HX-096) and MIC strip methods (CLSI); namely Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) was investigated using the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) methods. MIC results suggested that the NiO NPs and Gr/NiO NCs possess maximum growth inhibition of 86%, 82% and 94%, 92% at 50 and 30 µg/mL concentrations, respectively. Similarly, both nanomaterials were found to inhibit the ß-lacamase enzyme at concentrations of 60 µg/mL and 40 µg/mL, respectively. The cytotoxicity of NiO NPs and Gr/NiO NCs was quantified against A549 human lung cancer cells. Cell death percentage values of 52% at 50 µg/mL against NiO NPs and 54% at 20 µg/mL against Gr/NiO NCs were obtained, respectively. The NCs were found to reduce cell viability, increase the level of reactive oxygen species (ROS) and modify both the mitochondrial membrane permeability and cell cycle arrest.


Assuntos
Escherichia coli/enzimologia , Grafite/farmacologia , Nanocompostos/química , Níquel/farmacologia , Pseudomonas aeruginosa/enzimologia , beta-Lactamases/biossíntese , Células A549 , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Forma Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Klebsiella pneumoniae/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanocompostos/ultraestrutura , Pseudomonas aeruginosa/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
13.
Int J Nanomedicine ; 14: 2557-2571, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118605

RESUMO

Introduction: Global increase in the consumption of antibiotics has induced selective stress on wild-type microorganisms, pushing them to adapt to conditions of higher antibiotic concentrations, and thus an increased variety of resistant bacterial strains have emerged. Metal nanoparticles synthesized by green methods have been studied and proposed as potential antimicrobial agents against both wild-type and antibiotic-resistant strains; in addition, exopolysaccharides have been used as capping agent of metal nanoparticles due to their biocompatibility, reducing biological risks in a wide variety of applications. Purpose: In this work, we use an exopolysaccharide, from Rhodotorula mucilaginosa UANL-001L, an autochthonous strain from the Mexican northeast, as a capping agent in the synthesis of Zn, and Ni, nanoparticle biopolymer biocomposites. Materials and methods: To physically and chemically characterize the synthesized biocomposites, FT-IR, UV-Vs, TEM, SAED and EDS analysis were carried out. Antimicrobial and antibiofilm biological activity were tested for the biocomposites against two resistant clinical strains, a Gram-positive Staphylococcus aureus, and a Gram-negative Pseudomonas aeruginosa. Antimicrobial activity was determined using a microdilution assay whereas antibiofilm activity was analyzed through crystal violet staining. Results: Biocomposites composed of exopolysaccharide capped Zn and Ni metal nanoparticles were synthesized through a green synthesis methodology. The average size of the Zn and Ni nanoparticles ranged between 8 and 26 nm, respectively. The Ni-EPS biocomposites showed antimicrobial and antibiofilm activity against resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa at 3 and 2 mg/mL, respectively. Moreover, Zn-EPS biocomposites showed antimicrobial activity against resistant Staphylococcus aureus at 1 mg/mL. Both biocomposites showed no toxicity, as renal function showed no differences between treatments and control in the in vivo assays with male rats tests in this study at a concentration of 24 mg/kg of body weight. Conclusion: The exopolysaccharide produced by Rhodotorula mucilaginosa UANL-001L is an excellent candidate as a capping agent in the synthesis of biopolymer-metal nanoparticle biocomposites. Both Ni and Zn-EPS biocomposites demonstrate to be potential contenders as novel antimicrobial agents against both Gram-negative and Gram-positive clinically relevant resistant bacterial strains. Moreover, Ni-EPS biocomposites also showed antibiofilm activity, which makes them an interesting material to be used in different applications to counterattack global health problems due to the emergence of resistant microorganisms.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Biopolímeros/farmacologia , Nanopartículas Metálicas/química , Níquel/farmacologia , Polissacarídeos Bacterianos/farmacologia , Rhodotorula/metabolismo , Zinco/farmacologia , Animais , Antibacterianos/farmacologia , Masculino , Nanopartículas Metálicas/ultraestrutura , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos Wistar , Rhodotorula/efeitos dos fármacos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
14.
J Trace Elem Med Biol ; 54: 142-149, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31109604

RESUMO

BACKGROUND: Metal ions are essential for numerous life processes. This study aims to investigate the relationship between seminal quality and ion levels in seminal plasma. BASIC PROCEDURES: A total of 205 semen samples were collected and seminal plasma ion levels were examined with inductively-coupled plasma-mass spectrometry. The nickel function was demonstrated by in vitro assay and cell growth. MAIN FINDINGS: The low sperm motility group showed distinctively reduced nickel concentration in seminal plasma compared with the normal sperm motility group. However, arsenic, sulfur, selenium, magnesium and zinc were negatively associated with sperm quality. No significant relationship between other examined cations and semen quality was observed. In vitro assay suggested low concentration of nickel significantly increased sperm total motility and progressive motility. Cell growth assay further confirmed nickel promoted eukaryotic yeast cell growth. Nickel level in seminal plasma may play important functions to determine sperm quality. PRINCIPAL CONCLUSIONS: Our study reveals a strong correlation between S, Mg, Se, Zn, As, Ni and seminal quality as well as discovers a novel functional role of nickel in sperm motility and eukaryotic cell growth. These findings may provide a potential avenue for assessment of sperm quality and treatment of reproduction disorders.


Assuntos
Níquel/farmacologia , Motilidade Espermática/efeitos dos fármacos , Células Cultivadas , Células Eucarióticas/efeitos dos fármacos , Células Eucarióticas/metabolismo , Humanos , Masculino , Níquel/metabolismo , Estresse Oxidativo/fisiologia , Selênio/metabolismo , Sêmen/química , Motilidade Espermática/fisiologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Oligoelementos/metabolismo , Zinco/metabolismo
15.
Chemosphere ; 224: 884-891, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30986894

RESUMO

Comparative accumulation of cadmium (Cd) and nickel (Ni) and the consequences for the metabolism of common weed dandelion (triploid ones of Taraxacum sect. Taraxacum) were studied here for the first time. Cd accumulated more in both shoots and roots (489 and 2486 µg/g DW) than Ni (165 and 858 µg/g DW) after 14 days of exposure and only root Ni content did not increase between 7 and 14 days of exposure. Surprisingly, though Ni was less accumulated than Cd, it had more negative impact on basic physiology (root dry biomass, shoot water content and chlorophyll amount). Ni also evoked more extensive depression of mineral nutrients (K, Ca, Mg, and Mn) in the shoots than Cd while root potassium content was elevated by both metals. Ni suppressed accumulation of total thiols but anatomical changes and ROS formation (detected by fluorescence microscopy of total ROS and lipid peroxidation) were induced more by Cd. Total soluble phenols, major (caftaric and cichoric) and minor (chlorogenic and caffeic) phenolic acids were elevated by both metals and rather increased with prolonged exposure in the shoots (14 versus 7 days). On the contrary, typically depletion of these metabolites was found in the roots after prolonged exposure to Ni, but not to Cd. Data showed distinct toxicity of Cd and Ni in dandelion. More expressive tolerance of dandelion to Cd than to Ni indicates its potential use for the remediation of Cd-contaminated environment.


Assuntos
Cádmio/metabolismo , Níquel/metabolismo , Taraxacum/metabolismo , Biodegradação Ambiental , Cádmio/farmacologia , Cádmio/toxicidade , Hidroxibenzoatos , Peroxidação de Lipídeos , Níquel/farmacologia , Níquel/toxicidade , Nutrientes , Estresse Oxidativo/efeitos dos fármacos , Fenóis/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Espécies Reativas de Oxigênio
16.
Plant Physiol Biochem ; 139: 92-101, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30884416

RESUMO

Nickel oxide nanoparticles (NiO NPs) are utilized in various industries and their release into the environment may lead to the pollution of agricultural areas. However, assessing the toxicity of NiO NPs in major food crops is difficult due to the limited information available on their toxicity. The present investigation was carried out to evaluate how NiO NPs affect plant growth, photosynthetic efficiency, and phytochemical content, as well as changes at the transcriptional level of these phytochemicals in Chinese cabbage seedlings. Chlorophyll, carotenoid, and sugar contents were reduced, while proline and the anthocyanins were significantly upregulated in NiO NPs-treated seedlings. The levels of malondialdehyde, hydrogen peroxide, and reactive oxygen species, as well as peroxidase (POD) enzyme activity, were all enhanced in seedlings exposed to NiO NPs. The levels of glucosinolates and phenolic compounds were also significantly increased in NiO NPs-treated seedlings compared to control seedlings. The expression of genes related to oxidative stress (CAT, POD, and GST), MYB transcription factors (BrMYB28, BrMYB29, BrMYB34, and BrMYB51), and phenolic compounds (ANS, PAP1, and PAL) were significantly upregulated. We suggest that NiO NPs application stimulates toxic effects and enhances the levels of phytochemicals (glucosinolates and phenolic compounds) in Chinese cabbage seedlings.


Assuntos
Brassica rapa/efeitos dos fármacos , Nanopartículas Metálicas , Níquel/farmacologia , Antocianinas/metabolismo , Brassica rapa/metabolismo , Brassica rapa/fisiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Níquel/administração & dosagem , Prolina/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/fisiologia , Açúcares/metabolismo
17.
J Sci Food Agric ; 99(10): 4677-4685, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30906996

RESUMO

BACKGROUND: Heavy metal pollution may act as persistent selective pressure that favors the spread of antimicrobial resistance in natural environments. The aim of this study was to isolate and identify metal-tolerant bacteria from soils in olive tree fields routinely treated with copper-derived compounds and to evaluate the tolerance of bacterial strains to other metals and their resistance to clinically relevant antibiotics. RESULTS: Five hundred and ninety-five bacterial isolates from 45 olive tree agricultural fields were studied. Minimum inhibitory concentrations (MICs) ≥ 16 mmol L-1 were detected for copper (57% of isolates), zinc (37%) and lead (62%), while only 3% had MICs ≥ 12 mmol L-1 for nickel. Ninety-six metal-tolerant strains were selected for identification and antibiotic resistance determination. Most isolates belonged to the genera Pseudomonas (37%), Bacillus (23%) and Chryseobacterium (20%), while 6% were identified as Variovorax, 4% as Stenotrophomonas and 2% as Serratia or Burkholderia. Highest copper tolerance was detected among Pseudomonas. Over 75% of the strains with high copper tolerance were also resistant to vancomycin, 50% to ampicillin and 40% to erythromycin or trimethoprim/sulfamethoxazole. CONCLUSION: Bacteria from olive soils are tolerant to metals, mainly copper, but also zinc and lead, as well as resistant to clinically important antibiotics, which could be a troublesome issue in clinical settings. © 2019 Society of Chemical Industry.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cobre/farmacologia , Olea/crescimento & desenvolvimento , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana , Chumbo/farmacologia , Testes de Sensibilidade Microbiana , Níquel/farmacologia , Solo/química , Zinco/farmacologia
18.
Mater Sci Eng C Mater Biol Appl ; 98: 550-559, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30813058

RESUMO

The reactions of cobalt(II), nickel(II), zinc(II) chlorides and [Pd(DMSO)2Cl2] with 2-acetyl-5-chloro-thiophene thiosemicarbazone (HL) leads to the formation of a series of new complexes: [CoCl2(S-HL)2], 1; [Ni(N,S-L)2], 2 [ZnCl2(S-HL)2], 3 and [PdCl2(N,S-HL)], 4. All the complexes have been characterized by elemental analysis, IR, LC-MS. 1H and 13C NMR spectroscopy have been performed for Zn(II) and Pd(II) complexes. The crystal structures of the complexes 1-3 have been determined by single-crystal X-ray diffraction methods. The compounds, (1) and (3), crystallized in the monoclinic crystal system with C2/c space group. In both complexes, the metal centers are four-coordinated in a distorted tetrahedral configuration by two sulfur atoms from two thiosemicarbazone ligands and two Cl anions. The crystal structure of (2) consists of monomeric entities where the nickel(II) ion exhibit distorted square planar geometry. The coordination geometry around nickel ion is four-coordinate with four atoms of the two chelating thiosemicarbazone ligands which are in cis position. The τ4 value of 0.255 obtained from the τ4 analysis of complex (2) shows that the four-coordinate geometry around the central nickel ion is close to square planar. Complex (4) is mononuclear, the central ion is coordinated through the sulfur and the azomethine nitrogen atom of neutral ligand. The cytotoxic effects of all complexes were analyzed for three cancer cell lines, Caco-2, DLD-1, and SW620 compared to normal colon epithelial cell line, CCD18Co. Complex (4) is more active against DLD-1, SW620 and Caco-2 than CCD18Co. The efficiency of complex (4) is more effective in aggressive cancer cell lines. Therefore, it can be used as a new chemotherapeutic, especially in the treatment of resistant cancer types caused by long-term use of platinum-based drugs.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Cobalto/farmacologia , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Concentração Inibidora 50 , Ligantes , Conformação Molecular , Níquel/farmacologia , Paládio/farmacologia , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho , Tiossemicarbazonas/síntese química , Zinco/farmacologia
19.
Bioresour Technol ; 279: 404-409, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30712994

RESUMO

The bio-oil obtained from a general pyrolysis process contains a higher concentration of oxygenated compounds and the resultant physical and chemical properties make it an unsuitable drop-in fuel. The oxygenated compounds in the bio-oil can be converted into hydrocarbons or less oxygenated compounds with the application of catalysts. This study demonstrated the bio-oil upgrading with the application of catalysts, comparing the catalytic effect of combined mono-metallic catalysts (Cu/zeolite and Ni/zeolite) and sole bi-metallic catalyst (CuNi/zeolite) on the composition of bio-oil and pyrolytic gases. The results demonstrated that in comparison to the combined mono-metallic catalysts, the sole bi-metallic catalyst showed better deoxygenation for all the oxygenated compounds and favoured the production of aliphatic hydrocarbons, whereas the combination of mono-metallic catalysts generated higher proportion of aromatic hydrocarbons in the bio-oil. In both cases, the catalysts equally favoured decarboxylation and decarbonylation reactions, as CO2/CO of approximately 1 was obtained during the pyrolysis process.


Assuntos
Biomassa , Cobre/farmacologia , Níquel/farmacologia , Zeolitas/farmacologia , Biocombustíveis , Catálise , Temperatura Alta , Hidrocarbonetos/metabolismo , Pirólise/efeitos dos fármacos
20.
Ecotoxicology ; 28(3): 261-276, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30761430

RESUMO

Nickel (Ni), an essential nutrient of plant but very toxic to plant at supra-optimal concentration that causes inhibition of seed germination emergence and growth of plants as a consequence of physiological disorders. Hence, the present study investigates the possible mechanisms of Ni tolerance in rice seedlings by exogenous application of silicon (Si). Thirteen-day-old hydroponically grown rice (Oryza sativa L. cv. BRRI dhan54) were treated with Ni (NiSO4.7H2O, 0.25 and 0.5 mM) sole or in combination with 0.50 mM Na2SiO3 for a period of 3 days to investigate the effect of Si supply for revoking the Ni stress. Nickel toxicity gave rise to reactive oxygen species (ROS) and cytotoxic methylglyoxal (MG), accordingly, initiated oxidative stress in rice leaves, and accelerated peroxidation of lipids and consequent damage to membranes. Reduced growth, biomass accumulation, chlorophyll (chl) content, and water balance under Ni-stress were also found. However, free proline (Pro) content increased in Ni-exposed plants. In contrast, the Ni-stressed seedlings fed with supplemental Si reclaimed the seedlings from chlorosis, water retrenchment, growth inhibition, and oxidative stress. Silicon up-regulated most of the antioxidant defense components as well as glyoxalase systems, which helped to improve ROS scavenging and MG detoxification. Hence, these results suggest that the exogenous Si application can improve rice seedlings' tolerance to Ni-toxicity.


Assuntos
Antioxidantes/metabolismo , Níquel/farmacologia , Oryza/efeitos dos fármacos , Aldeído Pirúvico/metabolismo , Plântula/efeitos dos fármacos , Silício/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Níquel/metabolismo , Oryza/fisiologia , Estresse Oxidativo , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico
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