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1.
Mikrochim Acta ; 191(5): 267, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627300

RESUMO

A ternary hierarchical hybrid Ni@CoxSy/poly(3,4-ethylenedioxythiophene)-reduced graphene oxide (Ni@CoxSy/PEDOT-rGO) is rationally designed and in situ facilely synthesized as electrocatalyst to construct a binder-free sensing platform for non-enzymatic glucose monitoring through traditional electrodeposition procedure. The as-prepared Ni@CoxSy/PEDOT-rGO presents unique hierarchical structure and multiple valence states as well as strong and robust adhesion between Ni@CoxSy/PEDOT-rGO and GCE. Profiting from the aforementioned merits, the sensing platform constructed under optimal conditions achieved a wide detection range (0.2 µM ~ 2.0 mM) with high sensitivity (1546.32 µA cm-2 mM-1), a rapid response time (5 s), an ultralow detection limit (0.094 µM), superior anti-interference performance, excellent reproducibility and considerable stability. Furthermore, the sensor demonstrates an acceptable accuracy and appreciable recoveries ranging from 90.0 to 102.0% with less than 3.98% RSD in human blood serum samples, indicating the prospect of the sensor for the real samples analysis. It will provide a strategy to rationally design and fabricate ternary hierarchical hybrid as nanozyme for glucose assay.


Assuntos
Glicemia , Compostos Bicíclicos Heterocíclicos com Pontes , Cobalto , Grafite , Níquel , Polímeros , Humanos , Níquel/química , Glicemia/análise , Reprodutibilidade dos Testes , Automonitorização da Glicemia , Glucose/análise
2.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38612848

RESUMO

The rational design of advanced electrocatalysts at the molecular or atomic level is important for improving the performance of hydrogen evolution reactions (HERs) and replacing precious metal catalysts. In this study, we describe the fabrication of electrocatalysts based on Fe, Co, or Ni single atoms supported on titanium carbide (TiC) using the molten salt method, i.e., TiC-FeSA, TiC-CoSA, or TiC-NiSA, to enhance HER performance. The introduction of uniformly distributed transition-metal single atoms successfully reduces the overpotential of HERs. Overpotentials of TiC-FeSA at 10 mA cm-2 are 123.4 mV with 61.1 mV dec-1 Tafel slope under acidic conditions and 184.2 mV with 85.1 mV dec-1 Tafel slope under alkaline conditions, which are superior to TiC-NiSA and TiC-CoSA. TiC samples loaded with transition-metal single atoms exhibit high catalytic activity and long stability under acidic and basic conditions. Density functional theory calculations indicate that the introduction of transition-metal single atoms effectively reduces the HER barrier of TiC-based electrocatalysts.


Assuntos
Ferro , Níquel , Titânio , Cobalto , Hidrogênio
3.
Int J Mol Sci ; 25(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38612928

RESUMO

In this study, we explored the formation of CuO nanoparticles, NiO nanoflakes, and CuO-NiO nanocomposites using saponin extract and a microwave-assisted hydrothermal method. Five green synthetic samples were prepared using aqueous saponin extract and a microwave-assisted hydrothermal procedure at 200 °C for 30 min. The samples were pristine copper oxide (100C), 75% copper oxide-25% nickel oxide (75C25N), 50% copper oxide-50% nickel oxide (50C50N), 25% copper oxide-75% nickel oxide (25C75N), and pristine nickel oxide (100N). The samples were characterized using FT-IR, XRD, XPS, SEM, and TEM. The XRD results showed that copper oxide and nickel oxide formed monoclinic and cubic phases, respectively. The morphology of the samples was useful and consisted of copper oxide nanoparticles and nickel oxide nanoflakes. XPS confirmed the +2 oxidation state of both the copper and nickel ions. Moreover, the optical bandgaps of copper oxide and nickel oxide were determined to be in the range of 1.29-1.6 eV and 3.36-3.63 eV, respectively, and the magnetic property studies showed that the synthesized samples exhibited ferromagnetic and superparamagnetic properties. In addition, the catalytic activity was tested against para-nitrophenol, demonstrating that the catalyst efficiency gradually improved in the presence of CuO. The highest rate constants were obtained for the 100C and 75C25N samples, with catalytic efficiencies of 98.7% and 78.2%, respectively, after 45 min.


Assuntos
Nanocompostos , Níquel , Saponinas , Cobre , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Óxidos
4.
Wei Sheng Yan Jiu ; 53(2): 294-299, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604967

RESUMO

OBJECTIVE: To establish an analytical method for determining the migration of 24 elements in Yixing clay pottery in 4% acetic acid simulated solution by inductively coupled plasma mass spectrometry. METHODS: Four types of Yixing clay pottery, including Yixing clay teapot, Yixing clay kettle, Yixing clay pot, and Yixing clay electric stew pot, were immersed in 4% acetic acid as a food simulant for testing. The migration amount of 24 elements in the migration solution was determined using inductively coupled plasma mass spectrometry. RESULTS: Lithium, magnesium, aluminum, iron, and barium elements with a mass concentration of 1000 µg/L; Lead, cadmium, total arsenic, chromium, nickel, copper, vanadium, manganese, antimony, tin, zinc, cobalt, molybdenum, silver, beryllium, thallium, titanium, and strontium elements within 100 µg/L there was a linear relationship within, the r value was between 0.998 739 and 0.999 989. Total mercury at 5.0 µg/L, there was a linear relationship within, the r value of 0.995 056. The detection limit of the elements measured by this method was between 0.5 and 45.0 µg/L, the recovery rate was 80.6%-108.9%, and the relative standard deviation was 1.0%-4.8%(n=6). A total of 32 samples of four types of Yixing clay pottery sold on the market, including teapots, boiling kettles, casseroles, and electric stewing pots, were tested. It was found that the migration of 16 elements, including beryllium, titanium, chromium, nickel, cobalt, zinc, silver, cadmium, antimony, total mercury, thallium, tin, copper, total arsenic, molybdenum, and lead, were lower than the quantitative limit. The element with the highest migration volume teapot was aluminum, magnesium, and barium; The kettle was aluminum and magnesium; Casserole was aluminum, magnesium, and lithium; The electric stew pot was aluminum. CONCLUSION: This method is easy to operate and has high accuracy, providing an effective and feasible detection method for the determination and evaluation of element migration in Yixing clay pottery.


Assuntos
Arsênio , Mercúrio , Oligoelementos , Cobre , Molibdênio/análise , Níquel , Argila , Magnésio , Alumínio/análise , Cádmio/análise , Bário/análise , Titânio/análise , Prata/análise , Berílio/análise , Estanho/análise , Arsênio/análise , Lítio/análise , Antimônio/análise , Tálio/análise , Zinco , Cromo , Cobalto/análise , Mercúrio/análise , Espectrometria de Massas , Acetatos , Oligoelementos/análise
5.
BMC Plant Biol ; 24(1): 275, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605329

RESUMO

Heavy metals (HMs) contamination, owing to their potential links to various chronic diseases, poses a global threat to agriculture, environment, and human health. Nickel (Ni) is an essential element however, at higher concentration, it is highly phytotoxic, and affects major plant functions. Beneficial roles of plant growth regulators (PGRs) and organic amendments in mitigating the adverse impacts of HM on plant growth has gained the attention of scientific community worldwide. Here, we performed a greenhouse study to investigate the effect of indole-3-acetic acid (IAA @ 10- 5 M) and compost (1% w/w) individually and in combination in sustaining cauliflower growth and yield under Ni stress. In our results, combined application proved significantly better than individual applications in alleviating the adverse effects of Ni on cauliflower as it increased various plant attributes such as plant height (49%), root length (76%), curd height and diameter (68 and 134%), leaf area (75%), transpiration rate (36%), stomatal conductance (104%), water use efficiency (143%), flavonoid and phenolic contents (212 and 133%), soluble sugars and protein contents (202 and 199%), SPAD value (78%), chlorophyll 'a and b' (219 and 208%), carotenoid (335%), and NPK uptake (191, 79 and 92%) as compared to the control. Co-application of IAA and compost reduced Ni-induced electrolyte leakage (64%) and improved the antioxidant activities, including APX (55%), CAT (30%), SOD (43%), POD (55%), while reducing MDA and H2O2 contents (77 and 52%) compared to the control. The combined application also reduced Ni uptake in roots, shoots, and curd by 51, 78 and 72% respectively along with an increased relative production index (78%) as compared to the control. Hence, synergistic application of IAA and compost can mitigate Ni induced adverse impacts on cauliflower growth by immobilizing it in the soil.


Assuntos
Brassica , Compostagem , Ácidos Indolacéticos , Poluentes do Solo , Humanos , Níquel/metabolismo , Níquel/toxicidade , Brassica/metabolismo , Peróxido de Hidrogênio/metabolismo , Rizosfera , Clorofila A , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo
6.
Environ Monit Assess ; 196(5): 443, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607502

RESUMO

This study aims to assess the extent of heavy metals (HMs) pollution in soil and identify its potential sources using single and integrated pollution index calculations, and multivariate statistical analysis. The HM concentrations of soil samples were analyzed using ICP-MS. The concentrations (mg/kg) of arsenic (As) ranged from 2.8 to 208.1, cadmium (Cd) from 0.1 to 0.3, cobalt (Co) from 1.9 to 20.5, copper (Cu) from 3.7 to 17.7, nickel (Ni) from 14.7 to 110.6, and lead (Pb) from 6.7 to 37.3. High levels of As contents and physicochemical parameters were found in the northeastern parts of the study area, while levels of other HMs were high in the remaining parts. The HM contents of some soil samples exceeded the average values of basalt and limestone in the study area, as well as the upper, bulk, and lower continental crusts, shale, and soil (worldwide). Multiple index methods were used to assess the pollution risk, and it was determined that some soil samples were moderately to considerably contaminated with varying levels of As, Cd, Co, Ni, and Pb. Multivariate statistical analyses provided that the source of HMs contamination in the soil was a result of geogenic and/or anthropogenic activities. Geogenic sources were associated with weathering rock units, while anthropogenic sources were linked to industrial activities, traffic emissions, and agricultural applications. The findings are useful for detecting contamination by HMs in soil, and they could contribute to future monitoring programs to prevent soil contamination and protect the health of living organisms.


Assuntos
Arsênio , Metais Pesados , Cádmio , Chumbo , Monitoramento Ambiental , Cobalto , Níquel , Poluição Ambiental , Solo
7.
Environ Sci Technol ; 58(15): 6704-6715, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38574268

RESUMO

The transformation of toxic arsine (AsH3) gas into valuable elemental arsenic (As0) from industrial exhaust gases is important for achieving sustainable development goals. Although advanced arsenic removal catalysts can improve the removal efficiency of AsH3, toxic arsenic oxides generated during this process have not received adequate attention. In light of this, a novel approach for obtaining stable As0 products was proposed by performing controlled moderate oxidation. We designed a tailored Ni-based catalyst through an acid etching approach to alter interactions between Ni and NaY. As a result, the 1Ni/NaY-H catalyst yielded an unprecedented proportion of As0 as the major product (65%), which is superior to those of other reported catalysts that only produced arsenic oxides. Density functional theory calculations clarified that Ni species changed the electronic structure of oxygen atoms, and the formed [NiIII-OH (µ-O)] active centers facilitated the adsorption of AsH2*, AsH*, and As* reaction intermediates for As-H bond cleavage, thereby decreasing the direct reactivity of oxygen with the arsenic intermediates. This work presents pioneering insights into inhibiting excessive oxidation during AsH3 removal, demonstrating potential environmental applications for recovery of As0 from toxic AsH3.


Assuntos
Arsênio , Zeolitas , Níquel/química , Elétrons , Oxigênio , Gases
8.
Skin Res Technol ; 30(4): e13687, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566505

RESUMO

BACKGROUND: The physical appearance of an individual plays a primary role as it influences the opinion of the viewer. For this reason, orthodontic therapy to improve perceived aesthetics is in high demand among patients. This factor, combined with the increase in the number of non-invasive facial aesthetic treatments, has led to the need to understand potential risk factors in the application of medical devices to the perioral skin in patients with fixed orthodontic appliances. The aim of this study was to evaluate in vitro heating of the orthodontic bracket following electromagnetic fields and negative pressure (V-EMF) used as an anti-aging treatment. METHODS: Two different types of titanium alloy wires, one made of "beta-Titanium" alloy and the other "Ni-Ti" (DW Lingual Systems GmbH-Bad Essen-Germany) were used. The orthodontic wires and brackets mounted on a resin mouth were covered with porcine muscle tissue, then subjected to anti-aging therapy with a Bi-one LifeTouchTherapy medical device (Expo Italia Srl-Florence-Italy) which generates a combination of vacuum and electromagnetic fields (V-EMF) already adopted for antiaging therapy. During administration of the therapy, the orthodontic brackets and porcine tissue were thermally monitored using a Wavetek Materman TMD90 thermal probe (Willtek Communications GmbH-Germany). In total 20 orthodontic mouths were used, 10 with Beta Titanium wires and 10 with Nickel Titanium wires. RESULTS: A temperature increase of about 1°C was recorded in each group. The outcome of the present research shows that the absolute temperatures measured on orthodontic appliances, which, despite having a slightly different curve, both show an increase in temperature of 1.1°C at the end of the session, thus falling well within the safety range of 2°C as specified by the standard CENELEC EN 45502-1. Therefore, V-EMF therapy can be considered safe for the entire dental system and for metal prostheses, which tend to heat up at most as much as biological tissue (+0.9°C/1.1°C vs. 1.1°C/1.1°C). CONCLUSION: In conclusion, anti-aging therapy with V-EMF causes a thermal increase on orthodontic brackets that is not harmful to pulp health.


Assuntos
Campos Eletromagnéticos , Níquel , Titânio , Humanos , Animais , Suínos , Vácuo , Calefação , Fios Ortodônticos , Ligas , Teste de Materiais
9.
PLoS One ; 19(4): e0299896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568900

RESUMO

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.


Assuntos
Temperatura Alta , Níquel , Preparo de Canal Radicular , Microtomografia por Raio-X/métodos , Preparo de Canal Radicular/métodos , Ligas , Titânio , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/cirurgia , Desenho de Equipamento
10.
Mikrochim Acta ; 191(5): 252, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589716

RESUMO

A flexible, wearable, non-invasive contact lens sensor utilizing nickel-cobalt metal-organic framework (Ni-Co-MOF) based hydrogel is introduced for urea monitoring in tear samples. The synthesized Ni-Co-MOF hydrogel exhibits a porous structure with interconnected voids, as visualized by Scanning Electron Microscopy (SEM). Detailed structural and vibrational properties of the material were characterized using X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Raman spectroscopy. The developed Ni-Co-MOF hydrogel sensor showcases a detection limit of 0.445 mM for urea within a linear range of 0.5-70 mM. Notably, it demonstrates exceptional selectivity, effectively distinguishing against interfering species like UA, AA, glucose, dopamine, Cl-, K+, Na+, Ca2+, and IgG. The enhanced electrocatalytic performance of the Ni-Co-MOF hydrogel electrode is attributed to the presence of Ni and Co, fostering Ni2+ oxidation on the surface and forming a Co2+ complex that acts as a catalyst for urea oxidation. The fabricated sensor exhibits successful detection and retrieval of urea in simulated tear samples, showcasing promising potential for bioanalytical applications. The binder-free, non-toxic nature of the Ni-Co-MOF hydrogel sensor presents exciting avenues for future utilization in non-enzymatic electrochemical sensing, including applications in wearable devices, point-of-care diagnostics, and personalized healthcare monitoring.


Assuntos
Estruturas Metalorgânicas , Dispositivos Eletrônicos Vestíveis , Níquel/química , Estruturas Metalorgânicas/química , Ureia , Cobalto , Hidrogéis
11.
Neurotox Res ; 42(2): 24, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598025

RESUMO

The investigation into the hippocampal function and its response to heavy metal exposure is crucial for understanding the mechanisms underlying neurotoxicity, this can potentially inform strategies for mitigating the adverse effects associated with heavy metal exposure. Melatonin is an essential neuromodulator known for its efficacy as an antioxidant. In this study, we aimed to determine whether melatonin could protect against Nickel (Ni) neurotoxicity. To achieve this, we performed an intracerebral injection of Ni (300 µM NiCl2) into the right hippocampus of male Wistar rats, followed by melatonin treatment. Based on neurobehavioral and neurobiochemical assessments, our results demonstrate that melatonin efficiently enhances Ni-induced behavioral dysfunction and cognitive impairment. Specifically, melatonin treatment positively influences anxious behavior, significantly reduces immobility time in the forced swim test (FST), and improves learning and spatial memory abilities. Moreover, neurobiochemical assays revealed that melatonin treatment modulates the Ni-induced alterations in oxidative stress balance by increasing antioxidant enzyme activities, such as superoxide dismutase (SOD) and catalase (CAT). Additionally, we observed that melatonin significantly attenuated the increased levels of lipid peroxidation (LPO) and nitric oxide (NO). In conclusion, the data from this study suggests that melatonin attenuates oxidative stress, which is the primary mechanism responsible for Ni-induced neurotoxicity. Considering that the hippocampus is the main structure involved in the pathology associated with heavy metal intoxication, such as Ni, these findings underscore the potential therapeutic efficacy of melatonin in mitigating heavy metal-induced brain damage.


Assuntos
Melatonina , Síndromes Neurotóxicas , Masculino , Ratos , Animais , Antioxidantes/farmacologia , Melatonina/farmacologia , Melatonina/uso terapêutico , Níquel/toxicidade , Ratos Wistar , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/prevenção & controle
12.
Sci Rep ; 14(1): 8920, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637588

RESUMO

Land transportation is a major source of heavy metal contamination along the roadside, posing significant risks to human health through inhalation, oral ingestion, and dermal contact. Therefore, this study has been designed to determine the concentrations of vehicular released heavy metals (Cd, Pb, Ni, and Cu) in roadside soil and leaves of two commonly growing native plant species (Calotropis procera and Nerium oleander).Two busy roads i.e., Lahore-Okara road (N-5) and Okara-Faisalabad roads (OFR) in Punjab, Pakistan, were selected for the study. The data were collected from five sites along each road during four seasons. Control samples were collected ~ 50 m away from road. The metal content i.e. lead (Pb), cadmium (Cd) nickel (Ni) and copper (Cu) were determined in the plant leaves and soil by using Atomic Absorption Spectrophotometer (AAS). Significantly high amount of all studied heavy metals were observed in soil and plant leaves along both roads in contrast to control ones. The mean concentration of metals in soil ranged as Cd (2.20-6.83 mg/kg), Pb (4.53-15.29 mg/kg), Ni (29.78-101.26 mg/kg), and Cu (61.68-138.46 mg/kg) and in plant leaves Cd (0.093-0.53 mg/kg), Pb (4.31-16.34 mg/kg), Ni (4.13-16.34 mg/kg) and Cu (2.98-32.74 mg/kg). Among roads, higher metal contamination was noted along N-5 road. Significant temporal variations were also noted in metal contamination along both roads. The order of metal contamination in soil and plant leaves in different seasons was summer > autumn > spring > winter. Furthermore, the metal accumulation potential of Calotropis procera was higher than that of Nerium oleander. Therefore, for sustainable management of metal contamination, the plantation of Calotropis procera is recommended along roadsides.


Assuntos
Calotropis , Metais Pesados , Nerium , Poluentes do Solo , Humanos , Cádmio/análise , Solo , Biodegradação Ambiental , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Níquel , Plantas , Monitoramento Ambiental
14.
Pestic Biochem Physiol ; 200: 105807, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582579

RESUMO

Recently, nanotechnology is among the most promising technologies used in all areas of research. The production of metal nanoparticles using plant parts has received significant attention for its environmental friendliness and effectiveness. Therefore, we investigated the possible applications of biological synthesized nickel oxide nanoparticles (NiONPs). In this study, NiONPs were synthesized through biological method using an aqueous extract of saffron stigmas (Crocus sativus L). The structure, morphology, purity, and physicochemical properties of the obtained NPs were confirmed through Scanning/Transmission Electron Microscopy attached with Energy Dispersive Spectrum, X-ray Diffraction, and Fourier transform infrared. The spherically shaped NiONPs were found by Debye Scherer's formula to have a mean dimension of 41.19 nm. The application of NiONPs in vitro at 50, 100, and 200 µg/mL, respectively, produced a clear region of 2.0, 2.2, and 2.5 cm. Treatment of Xoo cell with NiONPs reduced the growth and biofilm formation, respectively, by 88.68% and 83.69% at 200 µg/mL. Adding 200 µg/mL NiONPs into Xoo cells produced a significant amount of ROS in comparison with the control. Bacterial apoptosis increased dramatically from 1.05% (control) to 99.80% (200 µg/mL NiONPs). When compared to the control, rice plants treated with 200 µg/mL NiONPs significantly improved growth characteristics and biomass. Interestingly, the proportion of diseased leaf area in infected plants with Xoo treated with NiONPs reduced to 22% from 74% in diseased plants. Taken together, NiONPs demonstrates its effectiveness as a promising tool as a nano-bactericide in managing bacterial infection caused by Xoo.


Assuntos
Nanopartículas Metálicas , Níquel , Oryza , Xanthomonas , Oryza/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
15.
Shanghai Kou Qiang Yi Xue ; 33(1): 54-58, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583025

RESUMO

PURPOSE: To compare the forming ability of four kinds of nickel-titanium instrument preparation resin for simulated curved root canal. METHODS: A total of 40 single bend resin simulated root canals were randomly divided into 4 groups with 10 in each group. Four kinds of nickel-titanium instruments (ProTaper, HyFlex EDM, WaveOne Gold and Reciproc Blue) were used for root canal preparation, and divided into group A, group B, group C and group D. The preparation time of the four groups was compared, the root canal images before and after preparation were analyzed by computer image analysis software, and the changes of the preparation time, curvature and curvature radius of the four groups were recorded. With the root tip as the center of the circle, the radius of 1-10 mm was selected as concentric circle arcs. The detection points were overlapping root canal intersection points. The resin removal amount and center positioning force of the inner and outer walls of the root canal at different detection points were recorded. Statistical analysis was performed with SPSS 20.0 software package. RESULTS: The root canal preparation time in group A was significant longer than that in group B, C and D(P<0.05), but there was no significant difference in the curvature and curvature radius of the root canal among the four groups (P>0.05). The removal amount of resin from the root canal wall in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 8, 9 and 10 mm, respectively. The removal amount of resin from the outer wall of the root canal in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 7, 9 and 10 mm, respectively. The root tip offset of group A from the detection point to the apical hole of 1, 2, 3, 4, 6, 7, 8, 9 and 10 mm was significant greater than that of group B, C and D(P<0.05). CONCLUSIONS: Among the four instruments, ProTaper has the largest apical deviation, HyFlex EDM, WaveOne Gold and Reciproc Blue have better ability of root canal forming.


Assuntos
Cavidade Pulpar , Titânio , Níquel , Instrumentos Odontológicos , Preparo de Canal Radicular/métodos , Desenho de Equipamento
16.
Physiol Plant ; 176(2): e14261, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527955

RESUMO

In response to our ever-increasing demand for metals, phytotechnologies are being developed to limit the environmental impact of conventional metal mining. However, the development of these technologies, which rely on plant species able to tolerate and accumulate metals, is partly limited by our lack of knowledge of the underlying molecular mechanisms. In this work, we aimed to better understand the role of metal transporters of the IRON REGULATED 1/FERROPORTIN (IREG/FPN) family from the nickel hyperaccumulator Leucocroton havanensis from the Euphorbiaceae family. Using transcriptomic data, we identified two homologous genes, LhavIREG1 and LhavIREG2, encoding divalent metal transporters of the IREG/FPN family. Both genes are expressed at similar levels in shoots, but LhavIREG1 shows higher expression in roots. The heterologous expression of these transporters in A. thaliana revealed that LhavIREG1 is localized to the plasma membrane, whereas LhavIREG2 is located on the vacuole. In addition, the expression of each gene induced a significant increase in nickel tolerance. Taken together, our data suggest that LhavIREG2 is involved in nickel sequestration in vacuoles of leaf cells, whereas LhavIREG1 is mainly involved in nickel translocation from roots to shoots, but could also be involved in metal sequestration in cell walls. Our results suggest that paralogous IREG/FPN transporters may play complementary roles in nickel hyperaccumulation in plants.


Assuntos
Proteínas de Transporte de Cátions , Níquel , Metais , Plantas/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo
17.
J Korean Med Sci ; 39(8): e77, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38442720

RESUMO

BACKGROUND: Considering the interactions between heavy metals, a comprehensive evaluation of the effects of exposure to various types of co-interacting heavy metals on health is required. This study assessed the association between dyslipidemia markers and blood mercury, lead, cadmium, iron, zinc, and nickel levels in residents of an abandoned refinery plant. METHODS: A total of 972 individuals (exposed group: 567, control group: 405) living near the Janghang refinery plant in the Republic of Korea were included. Blood mercury, lead, cadmium, iron, zinc, nickel, cholesterol, and triglyceride levels were measured. The combined effect of the six heavy metals on dyslipidemia markers was evaluated using a Bayesian kernel machine regression (BKMR) model and compared with the results of a linear regression analysis. The BKMR model results were compared using a stratified analysis of the exposed and control groups. RESULTS: In the BKMR model, the combined effect of the six heavy metals was significantly associated with total cholesterol (TC) levels both below the 45th percentile and above the 55th percentile in the total population. The combined effect range between the 25th and 75th percentiles of the six metals on TC levels was larger in the exposed group than that in the total population. In the control group, the combined effects of the changes in concentration of the six heavy metals on the TC concentration were not statistically significant. CONCLUSION: These results suggest that the cholesterol levels of residents around the Janghang refinery plant may be elevated owing to exposure to multiple heavy metals.


Assuntos
Dislipidemias , Mercúrio , Metais Pesados , Humanos , Cádmio , Níquel , Teorema de Bayes , Zinco , Ferro , República da Coreia
18.
Ecotoxicol Environ Saf ; 273: 116150, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430579

RESUMO

Nickel (Ni), an environmental health hazard, is nephrotoxic to humans, but the exact mechanism is unknown. This study aims to identify whether nephrotoxicity is associated with autophagy. Here, nickel chloride (NiCl2) increased autophagy in TCMK-1 cells. NiCl2 induces autophagy through Akt and AMPK/mTOR pathways. Next, oxidative stress was investigated in NiCl2-induced autophagy. The findings demonstrated that the antioxidant (NAC) or mitochondrial targeted antioxidant (Mito-TEMPO) attenuated NiCl2-induced autophagy, reversed the influence on AMPK-mTOR and Akt pathways. Additionally, our study examined the role of autophagy in NiCl2-induced nephrotoxicity. Autophagy inhibition with 3-MA could inhibit cell viability and increase apoptosis in the TCMK-1 cells, however, autophagy promotion with rapamycin relieved cytotoxicity and decreased apoptosis. Additionally, co-treatment with Z-VAD-FMK reduced cytotoxicity, but did not affect autophagy. Besides, NiCl2 can increase the level of mitophagy in vivo and vitro. Mitophagy inhibition could inhibit cell viability and increase apoptosis in the TCMK-1 cells, whereas, promotion of mitophagy could increase cell viability and decrease apoptosis. In summary, above-mentioned results showed that NiCl2 induces autophagy in TCMK-1 cells through oxidative stress-dependent AMPK/AKT-mTOR pathway, autophagy plays a role in reducing NiCl2-induced renal toxicity, and a major mechanism in autophagy's inhibitory effect on NiCl2-induced apoptosis may be mitophagy.


Assuntos
Antioxidantes , Proteínas Proto-Oncogênicas c-akt , Humanos , Antioxidantes/farmacologia , Níquel/toxicidade , Proteínas Quinases Ativadas por AMP/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Autofagia
19.
Int J Biol Macromol ; 265(Pt 2): 131046, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518945

RESUMO

This work aims to fabricate antibacterial natural rubber latex composites by introducing different ratios of graphene oxide (GO) and nickel oxide (NiO) nanoparticles. The nanocomposites were prepared using latex mixing and a two-roll mill process, followed by molding with a heating hydraulic press. Detailed analyses were conducted to evaluate the rheological, chemical, physical, thermal, mechanical, and electrical performance of the composites. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the interaction among different components, while the surface morphology was examined through the field emission scanning electron microscopy (FESEM) technique. The composites with a loading ratio of 1:2 of GO to NiO (optimized concentration) exhibited the highest tensile strength (24.9 MPa) and tear strength (47.4 N/ mm) among all the tested samples. In addition, the composites demonstrated notable antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The thermal stability of the composites was observed up to 315 °C, and their electrical resistivity lies in the insulating range across a temperature span of 25 °C to 50 °C. The research uncovers critical insights into advancing composite materials suitable for diverse applications, featuring inherent antibacterial attributes, robust mechanical properties, resilience to solvent, UV shielding properties, and controlled electrical resistivity capabilities.


Assuntos
Grafite , Nanopartículas , Níquel , Borracha , Borracha/química , Látex/química , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química
20.
ACS Appl Bio Mater ; 7(4): 2499-2510, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38517141

RESUMO

As important biomarkers of many diseases, glycoproteins are of great significance to biomedical science. It is essential to develop efficient glycoprotein enrichment platforms and investigate their adsorption mechanism. In this work, a conspicuous enrichment strategy for glycoproteins was developed by using an electrospun fiber membrane wrapped with polydopamine (PDA) and modified with 3-aminophenylboronic acid and nickel ions, named PAN/DA@PDA@APBA/Ni. The enrichment characteristics of PAN/DA@PDA@APBA/Ni toward glycoproteins were explored through adsorption behavior. Thanks to the existence of two sites of interaction (metal ion chelation and boronate affinity), PAN/DA@PDA@APBA/Ni exhibited significant enrichment capacity for glycoproteins, ovalbumin (604.6 mg/g), and human immunoglobulin G (331.0 mg/g). The adsorption kinetic results of glycoprotein ovalbumin on PAN/DA@PDA@APBA/Ni conform to the pseudo-first-order kinetic model in the first adsorption stage, while the second half adsorption stage is more in line with the pseudo-second-order kinetic model. Moreover, the physical characteristics of PAN/DA@PDA@APBA/Ni and subsequent adsorption experiments on electrospun fiber modified with only phenylboronic acid or nickel ions both confirmed two sites of interaction (metal ion chelation and boronate affinity, respectively). Furthermore, a stepwise elution method with dual-affinity interaction was designed and successfully applied to enrich glycoproteins in real biological samples. This work provides an idea for sample pretreatment, especially for the design of dual-affinity materials in glycoproteins enrichment.


Assuntos
Glicoproteínas , Níquel , Humanos , Ovalbumina , Adsorção , Íons
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