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1.
Talanta ; 233: 122553, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215056

RESUMO

Due to many roles of trace elements such as Fe, Cu and Zn in various physiological and pathophysiological processes, their determination in serum and plasma is of high clinical relevance. In the present study, for the first time, the effect of serum and plasma preparation parameters (dilution factor and sample deposition volume) on the quality of results obtained by TXRF analysis was evaluated by means of experimental design tools (response surface analysis). It was found that the best strategy was the direct analysis of both human fluids without a previous dilution step. The accuracy and precision of the proposed methods were evaluated by analysis of reference materials (ClinChek® Plasma Control Level II and Seronorm™ Trace Elements Serum L-1). TXRF results agreed with the reference values and no significant differences at 95% confidence level were found. Limits of detection for the elements of interest were also adequate, taking into account their typical concentration ranges in real serum and plasma samples. Finally, the developed TXRF methods were applied to a set of serum and plasma samples from patients with different genders, ages and diagnoses, previously analysed by ICP-OES and ICP-MS techniques. The results showed good agreement between both analytical approaches. These results suggest that the proposed TXRF method provides reliable results thus being suitable for plasma and serum analysis, but in a simpler and more sustainable way.


Assuntos
Cobre , Oligoelementos , Feminino , Humanos , Ferro , Masculino , Soro/química , Espectrometria por Raios X , Oligoelementos/análise , Zinco
2.
Mater Sci Eng C Mater Biol Appl ; 127: 112242, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225882

RESUMO

Electrospun porous bone scaffolds are known to imitate the extracellular matrix very well and provide an environment through which the tissue formation is enhanced. Although polymeric scaffolds have a great potential in bone tissue regeneration, their weak bioactivity (bone bonding ability) and mechanical properties have left room for improvement. Therefore, the present study focused on the developing a ternary multifunctional platform composed of polycaprolactone (PCL)/silk fibroin (SF)/Zn-substituted Mg2SiO4 nanoparticles for bone tissue regeneration. This study is composed of two connected sections including synthesis and characterization of Mg(2-x)ZnxSiO4, x = 0, 0.5, 1, 1.5, 2 through surfactant-assisted sol-gel technique followed by incorporation of the nanoparticles into PCL/SF hybrid scaffold via electrospinning technique. The weight ratios of polymers and ceramic nanoparticles were optimized to reach desirable textural-porosity, pore size, and fiber diameter-and mechanical properties. Having optimized the ternary scaffold, it was then undergone different physical, chemical, and biological tests in vitro. A precise comparison study between the ternary (PCL/SF/ceramic nanoparticles), binary (PCL/SF), and pure PCL was made to shed light on the effect of each composition on the applicability of ternary scaffold. The overall results confirmed that the Mg1Zn1SiO4 nanoparticles-incorporated PCL/SF scaffold with fluorescence property was the one yielding the highest Young's modulus and desirable textural properties. The ternary scaffold showed improved biological properties making it a promising candidate for further studies towards bone tissue regeneration.


Assuntos
Fibroínas , Nanopartículas , Regeneração Óssea , Poliésteres , Engenharia Tecidual , Tecidos Suporte , Zinco
3.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198528

RESUMO

Intracellular free zinc ([Zn2+]i) is mobilized in neuronal and non-neuronal cells under physiological and/or pathophysiological conditions; therefore, [Zn2+]i is a component of cellular signal transduction in biological systems. Although several transporters and ion channels that carry Zn2+ have been identified, proteins that are involved in Zn2+ supply into cells and their expression are poorly understood, particularly under inflammatory conditions. Here, we show that the expression of Zn2+ transporters ZIP8 and ZIP14 is increased via the activation of hypoxia-induced factor 1α (HIF-1α) in inflammation, leading to [Zn2+]i accumulation, which intrinsically activates transient receptor potential ankyrin 1 (TRPA1) channel and elevates basal [Zn2+]i. In human fibroblast-like synoviocytes (FLSs), treatment with inflammatory mediators, such as tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α), evoked TRPA1-dependent intrinsic Ca2+ oscillations. Assays with fluorescent Zn2+ indicators revealed that the basal [Zn2+]i concentration was significantly higher in TRPA1-expressing HEK cells and inflammatory FLSs. Moreover, TRPA1 activation induced an elevation of [Zn2+]i level in the presence of 1 µM Zn2+ in inflammatory FLSs. Among the 17 out of 24 known Zn2+ transporters, FLSs that were treated with TNF-α and IL-1α exhibited a higher expression of ZIP8 and ZIP14. Their expression levels were augmented by transfection with an active component of nuclear factor-κB P65 and HIF-1α expression vectors, and they could be abolished by pretreatment with the HIF-1α inhibitor echinomycin (Echi). The functional expression of ZIP8 and ZIP14 in HEK cells significantly increased the basal [Zn2+]i level. Taken together, Zn2+ carrier proteins, TRPA1, ZIP8, and ZIP14, induced under HIF-1α mediated inflammation can synergistically change [Zn2+]i in inflammatory FLSs.


Assuntos
Proteínas de Transporte de Cátions/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/genética , Sinoviócitos/metabolismo , Canal de Cátion TRPA1/genética , Regulação para Cima/genética , Zinco/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Inflamação/patologia , Espaço Intracelular/metabolismo , Sinoviócitos/patologia , Canal de Cátion TRPA1/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-34204028

RESUMO

Lead, zinc, and cadmium were used to prepare a composite-contaminated soil to replicate common situations, in which soil is usually simultaneously contaminated by multiple metals. To examine the long-term durability of stabilized/solidified (S/S) contaminated soil, specimens were subjected to a series of freeze-thaw (F-T) cycles, up to ninety times (one day per cycle), prior to testing. Triaxial compression tests, soil column leaching tests, and X-ray diffraction analysis were then employed to study the mechanical properties, environmental influences, and micro-mechanisms of the S/S lead-zinc-cadmium composite-contaminated soils after long-term F-T. The results showed that triaxial compressive strength increases within three F-T cycles, then decreases before slightly increasing or stabilizing after thirty F-T cycles. The stage of decreased cohesion thus occurs between three and fourteen F-T cycles, with variation in other factors similar to that of the triaxial compressive strength. The cohesion mainly increases between three and seven cycles. The soil column leaching test showed that the permeability of soil is more than four times higher than that of soil not subject to freeze-thaw cycles after ninety F-T cycles. XRD tests further revealed that the chemical composition of S/S contaminated soil and the occurrence of each heavy metal (HM) remained unchanged under F-T treatment.


Assuntos
Cádmio , Poluentes do Solo , Chumbo , Solo , Poluentes do Solo/análise , Zinco
5.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199627

RESUMO

Investigating metal-ion solvation-in particular, the fundamental binding interactions-enhances the understanding of many processes, including hydrogen production via catalysis at metal centers and metal corrosion. Infrared spectra of the hydrated zinc dimer (Zn2+(H2O)n; n = 1-20) were measured in the O-H stretching region, using infrared multiple photon dissociation (IRMPD) spectroscopy. These spectra were then compared with those calculated by using density functional theory. For all cluster sizes, calculated structures adopting asymmetric solvation to one Zn atom in the dimer were found to lie lower in energy than structures adopting symmetric solvation to both Zn atoms. Combining experiment and theory, the spectra show that water molecules preferentially bind to one Zn atom, adopting water binding motifs similar to the Zn+(H2O)n complexes studied previously. A lower coordination number of 2 was observed for Zn2+(H2O)3, evident from the highly red-shifted band in the hydrogen bonding region. Photodissociation leading to loss of a neutral Zn atom was observed only for n = 3, attributed to a particularly low calculated Zn binding energy for this cluster size.


Assuntos
Metais/química , Modelos Moleculares , Água/química , Zinco/química , Cátions/química , Ligação de Hidrogênio , Fótons
6.
Sensors (Basel) ; 21(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203521

RESUMO

This paper presents a fully transparent and sensitivity-programmable biosensor based on an amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) with embedded resistive switching memories (ReRAMs). The sensor comprises a control gate (CG) and a sensing gate (SG), each with a resistive switching (RS) memory connected, and a floating gate (FG) that modulates the channel conductance of the a-IGZO TFT. The resistive coupling between the RS memories connected to the CG and SG produces sensitivity properties that considerably exceed the limit of conventional ion-sensitive field-effect transistor (ISFET)-based sensors. The resistances of the embedded RS memories were determined by applying a voltage to the CG-FG and SG-FG structures independently and adjusting the compliance current. Sensors constructed using RS memories with different resistance ratios yielded a pH sensitivity of 50.5 mV/pH (RCG:RSG = 1:1), 105.2 mV/pH (RCG:RSG = 2:1), and 161.9 mV/pH (RCG:RSG = 3:1). Moreover, when the RCG:RSG = 3:1, the hysteresis voltage width (VH) and drift rate were 54.4 mV and 32.9 mV/h, respectively. As the increases in VH and drift rate are lower than the amplified sensitivity, the sensor performs capably. The proposed device is viable as a versatile sensing device capable of detecting various substances, such as cells, antigens, DNA, and gases.


Assuntos
Técnicas Biossensoriais , Gálio , Óxido de Zinco , Índio , Transistores Eletrônicos , Zinco
7.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208159

RESUMO

B-cell lymphoma 2 (Bcl-2) and cytochrome c (Cycs) are two important proteins relevant to cellular apoptosis. In this study, we characterized the functions of the promoter regions of two apoptosis-related genes, Bcl-2 and Cycs, in yellow catfish Pelteobagrus fulvidraco. We obtained a 1989 bp Bcl-2 promoter and an 1830 bp Cycs promoter and predicted several key transcription factor binding sites (TFBSs) on the promoters, such as Kruppel-like factor 4 (KLF4), signal transducer and activator of transcription factor 3 (STAT3), forkhead box O (FOXO), metal-responsive element (MRE) and hepatocyte nuclear factor 1α (HNF-1α). Zinc (Zn) increased the activities of the Bcl-2 promoter but decreased the activities of the Cycs promoter. Metal-responsive transcription factor 1 (MTF-1) and HNF-1α directly bound with Bcl-2 and Cycs promoters, and they positively regulated the activity of the Bcl-2 promoter but negatively regulated the activity of the Cycs promoter. Zn promoted the binding ability of HNF-1α to the Bcl-2 promoter but decreased its binding ability to the Cycs promoter. However, Zn had no significant effect on the binding capability of MTF-1 to the regions of Bcl-2 and Cycs promoters. Zn upregulated the mRNA and total protein expression of Bcl-2 but downregulated the mRNA and total protein expression of Cycs. At the same time, Annexin V-FITC/PI staining showed that Zn significantly reduced the apoptosis of primary hepatocytes. For the first time, our study provides evidence for the MRE and HNF-1α response elements on the Bcl-2 and Cycs promoters, offering new insight into the mechanism by which Zn affects apoptosis in vertebrates.


Assuntos
Apoptose/genética , Peixes-Gato/genética , Citocromos c/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Zinco/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Sítios de Ligação , Citocromos c/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Deleção de Sequência
8.
BMJ Case Rep ; 14(6)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193450

RESUMO

A 3-month-old, full term female infant, adequate for gestational age, and exclusively breastfed, was admitted with a 10 day history of generalised scaling erythematous dermatitis, affecting the face (perinasal, nasolabial folds and periauricular), acral and intertriginous areas, with irritability and failure to thrive. Her mother had been treated with isoniazid since the third trimester because of family contact with tuberculosis. Based on a diagnosis of suspected impetiginised eczema, the infant was treated with flucloxacillin and prednisolone, and maternal isoniazid was suspended, with no improvement. Investigations found low serum zinc levels in the infant (33 µg/dL; normal range (NR) >60 µg/dL), normal plasma zinc levels in the mother (111.3 µg/dL; NR 68-120 µg/dL) and lower than the normal range of zinc levels in breast milk (270µg/L; NR 1000-2500 µg/L), suggesting acrodermatitis caused by zinc deficiency. Oral zinc supplementation (3 mg/kg/day) was started with a marked improvement in skin lesions, as well as good weight gain. At the age of 6 months, after food diversification, supplementation was suspended, without any recurrence of symptoms.


Assuntos
Acrodermatite , Desnutrição , Acrodermatite/diagnóstico , Acrodermatite/tratamento farmacológico , Acrodermatite/etiologia , Aleitamento Materno , Feminino , Humanos , Lactente , Leite Humano/química , Zinco
9.
Molecules ; 26(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200394

RESUMO

Zinc is an effective anti-inflammatory and antioxidant trace element. The aim of this study was to analyse the protective effect of zinc and zinc-prolactin systems as additives of preservation solutions in the prevention of nephron damage caused during ischemia. The study used a model for storing isolated porcine kidneys in Biolasol®. The solution was modified with the addition of Zn at a dose of 1 µg/L and Zn: 1 µg/L with prolactin (PRL): 0.1 µg/L. After 2 h and 48 h of storage, the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, sodium, potassium, creatinine and total protein were determined. Zinc added to the Biolasol® composition at a dose of 1 µg/L showed minor effectiveness in the protection of nephrons. In turn, Zn2+ added to Biolasol + PRL (PRL: 0.1 µg/L) acted as a prolactin inhibitor. We do not recommend the addition of Zn(II) (1 µg/L) and Zn(II) (1 µg/L) + PRL (0.1 µg/L) to the Biolasol solution.


Assuntos
Isquemia/metabolismo , Rim/metabolismo , Prolactina/metabolismo , Zinco/metabolismo , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Creatinina/metabolismo , Criopreservação/métodos , L-Lactato Desidrogenase/metabolismo , Preservação de Órgãos/métodos , Perfusão/métodos , Potássio/metabolismo , Sódio/metabolismo , Suínos
10.
Nutrients ; 13(6)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203015

RESUMO

The interplay between inflammation and oxidative stress is a vicious circle, potentially resulting in organ damage. Essential micronutrients such as selenium (Se) and zinc (Zn) support anti-oxidative defense systems and are commonly depleted in severe disease. This single-center retrospective study investigated micronutrient levels under Se and Zn supplementation in critically ill patients with COVID-19 induced acute respiratory distress syndrome (ARDS) and explored potential relationships with immunological and clinical parameters. According to intensive care unit (ICU) standard operating procedures, patients received 1.0 mg of intravenous Se daily on top of artificial nutrition, which contained various amounts of Se and Zn. Micronutrients, inflammatory cytokines, lymphocyte subsets and clinical data were extracted from the patient data management system on admission and after 10 to 14 days of treatment. Forty-six patients were screened for eligibility and 22 patients were included in the study. Twenty-one patients (95%) suffered from severe ARDS and 14 patients (64%) survived to ICU discharge. On admission, the majority of patients had low Se status biomarkers and Zn levels, along with elevated inflammatory parameters. Se supplementation significantly elevated Se (p = 0.027) and selenoprotein P levels (SELENOP; p = 0.016) to normal range. Accordingly, glutathione peroxidase 3 (GPx3) activity increased over time (p = 0.021). Se biomarkers, most notably SELENOP, were inversely correlated with CRP (rs = -0.495), PCT (rs = -0.413), IL-6 (rs = -0.429), IL-1ß (rs = -0.440) and IL-10 (rs = -0.461). Positive associations were found for CD8+ T cells (rs = 0.636), NK cells (rs = 0.772), total IgG (rs = 0.493) and PaO2/FiO2 ratios (rs = 0.504). In addition, survivors tended to have higher Se levels after 10 to 14 days compared to non-survivors (p = 0.075). Sufficient Se and Zn levels may potentially be of clinical significance for an adequate immune response in critically ill patients with severe COVID-19 ARDS.


Assuntos
COVID-19/tratamento farmacológico , Estado Terminal/terapia , Deficiências Nutricionais/tratamento farmacológico , Suplementos Nutricionais , Micronutrientes/uso terapêutico , Selênio/uso terapêutico , Zinco/uso terapêutico , Idoso , Proteína C-Reativa/metabolismo , COVID-19/sangue , COVID-19/imunologia , Deficiências Nutricionais/complicações , Humanos , Sistema Imunitário/efeitos dos fármacos , Inflamação/sangue , Inflamação/tratamento farmacológico , Unidades de Terapia Intensiva , Interleucinas/sangue , Masculino , Micronutrientes/sangue , Micronutrientes/deficiência , Pessoa de Meia-Idade , Oxigênio/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Estudos Retrospectivos , SARS-CoV-2 , Selênio/sangue , Selênio/deficiência , Selenoproteína P/sangue , Índice de Gravidade de Doença , Zinco/sangue , Zinco/deficiência
11.
J Evid Based Integr Med ; 26: 2515690X211026193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34225463

RESUMO

OBJECTIVES AND SETTING.: As the lethal COVID-19 pandemic enters its second year, the need for effective modalities of alleviation remains urgent. This includes modalities that can readily be used by the public to reduce disease spread and severity. Such preventive measures and early-stage treatments may temper the immediacy of demand for advanced anti-COVID measures (drugs, antibodies, vaccines) and help relieve strain also on other health system resources. DESIGN AND PARTICIPANTS.: We present results of a clinical study with a multi-component OTC "core formulation" regimen used in a multiply exposed adult population. Analysis of clinical outcome data from our sample of over 100 subjects - comprised of roughly equal sized regimen-compliant (test) and non-compliant (control) groups meeting equivalent inclusion criteria - demonstrates a strong statistical significance in favor of use of the core formulations. RESULTS.: While both groups were moderate in size, the difference between them in outcomes over the 20-week study period was large and stark: Just under 4% of the compliant test group presented flu-like symptoms, but none of the test group was COVID-positive; whereas 20% of the non-compliant control group presented flu-like symptoms, three-quarters of whom (15% overall of the control group) were COVID-positive. CONCLUSIONS.: Offering a low cost, readily implemented anti-viral approach, the study regimen may serve, at the least, as a stopgap modality and, perhaps, as a useful tool in combatting the pandemic.


Assuntos
Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , Controle de Doenças Transmissíveis , Suplementos Nutricionais , Pandemias , Adulto , COVID-19/virologia , Cinchona , Feminino , Humanos , Ionóforos/uso terapêutico , Lisina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Medicamentos sem Prescrição , Quercetina/uso terapêutico , SARS-CoV-2 , Índice de Gravidade de Doença , Resultado do Tratamento , Vitaminas/uso terapêutico , Zinco/uso terapêutico
12.
Mymensingh Med J ; 30(3): 609-612, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34226445

RESUMO

Adolescent girls are vulnerable in underdeveloped and developing countries due to having public health problems regarding iron deficiency anaemia. As zinc acts as a cofactor in iron metabolism, so the deficiency of this trace element is associated with iron deficiency anaemia. This study was done to evaluate the changes of serum iron and serum zinc levels among iron deficient anaemic adolescent girls in comparison to healthy adolescent girls in Bangladesh. This prospective type of analytical cross sectional study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2019 to December 2020. Total number of 140 adolescent girl's age ranged from10-19 years included in this study. Among them, 70 healthy adolescent girls, were taken as control group (Group I). Remaining 70 Adolescent girls with iron deficiency anaemia (IDA) were taken as study group (Group II). Estimation of serum iron was determined by Ferrozine method using Globals iron kit, UK. Serum zinc levels were determined by colorimetric method with reagents. All data were expressed as mean (±SD) and statistical significance of difference among the group I ( healthy adolescent girls) and group II (adolescent girls with iron deficiency anaemia) were calculated by unpaired students' 't' test. Correlation of serum iron with serum zinc was done by Pearson's correlation coefficient test. The mean values (±SD) of serum iron level of Group I and Group II were 69.06±18.11µg/dl & 15.61±9.12µg/dl respectively. Mean values (±SD) of serum iron significantly lower in study group (Group II) in comparison with control group (Group I). The mean (±SD) of serum zinc level of Group I and Group II were 75.48±14.26µg/dl & 33.27±12.94µg/dl respectively. Mean value (±SD) of serum zinc levels were significantly lower in study group (Group II) in comparison with control group (Group I). Serum zinc level was positively correlated with serum iron and that was statistically significant. The deficiency of iron does not occur alone; rather it is typically associated and developed with hypozincemia. The study suggests on supplementing iron along with zinc to correct the deficiency especially in adolescent girls when their metabolic demand is high.


Assuntos
Anemia Ferropriva , Adolescente , Adulto , Anemia Ferropriva/epidemiologia , Bangladesh/epidemiologia , Criança , Estudos Transversais , Feminino , Humanos , Ferro , Estudos Prospectivos , Adulto Jovem , Zinco
13.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2007-2013, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212605

RESUMO

To explore the effects of zinc levels on the synthesis and translocation of photosynthetic products from leaves to fruits, and to lay a theoretical foundation for improving fruit quality through zinc supplementation during the critical period of apple fruit development, a field experiment was carried out with a eight-year old 'Hanfu'/GM256/Malus baccata Borkh apple. We used the 13C tracer method to examine the effects of different zinc levels (ZnSO4·H2O 0, 0.1%, 0.2%, 0.3%, 0.4%, expressed by CK, Zn1, Zn2, Zn3, Zn4, respectively) on translocation of photosynthate to fruit during the stage of fruit expanding. The results showed that, with increasing zinc concentration, Rubisco enzyme activity, net photosynthetic rate, sorbitol and sucrose content, sorbitol 6-phosphate dehydrogenase, and sucrose phosphate synthase enzyme activities of leaves first increased and then decreased, with the highest values being observed in Zn3 treatment. Zn3 treatment significantly increased the 13C assimilation capability of leaves. Compared with other treatments, the 13C of self-retention (labeled leaves and labeled branches) was lowest in Zn3 treatment (61.2%) and the output of 13C photoassimilates was highest in Zn3 treatment (38.8%). 13C absorption of apple fruit showed a trend of Zn3 > Zn2 > Zn4 > Zn1 > CK. In summary, foliar zinc application under appropriate concentration (0.3% ZnSO4·H2O) enhanced photosynthesis, increased the assimilation capability of leaves, and promoted the directional transportation of photosynthate to fruit.


Assuntos
Malus , Frutas , Fotossíntese , Folhas de Planta , Zinco
14.
Nutrients ; 13(5)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066470

RESUMO

The purpose of this work was to evaluate the effect of the nanosized or microsized zinc (Zn) particles on fatty acid profile, enzyme activity and the level of cholesterol, squalene and oxysterols in rats with breast cancer. Rats (female, n = 24) were divided into the following groups: control, and two test groups, whose diets were enriched with either Zn microparticles (342 nm) or Zn nanoparticles (99 nm). All rats were treated twice with the carcinogenic agent; 7,12-dimethylbenz[a]anthracene. In rats whose diet was enriched with zinc (especially in the form of nanoparticles), the number and sizes of tumors were lower. Diet supplementation also significantly reduced the cholesterol (p = 0.027) and COPs (cholesterol oxidation products) levels (p = 0.011) in rats serum. Enriching the diet with Zn microparticles decreased the Δ6-desaturase activity (p < 0.001). Zn influences fatty acids' profile in rats' serum as well as inhibiting desaturating enzymes. A reduced amount of pro-inflammatory arachidonic acid derivatives may be the expected effect.


Assuntos
Neoplasias da Mama/dietoterapia , Suplementos Nutricionais , Alimentos Fortificados , Nanopartículas Metálicas/administração & dosagem , Zinco/administração & dosagem , 9,10-Dimetil-1,2-benzantraceno , Animais , Neoplasias da Mama/induzido quimicamente , Colesterol/sangue , Colesterol Oxidase/sangue , Modelos Animais de Doenças , Ácidos Graxos/sangue , Feminino , Linoleoil-CoA Desaturase/sangue , Tamanho da Partícula , Ratos , Carga Tumoral
15.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065496

RESUMO

The most critical group of all includes multidrug resistant bacteria that pose a particular threat in hospitals, as they can cause severe and often deadly infections. Modern medicine still faces the difficult task of developing new agents for the effective control of bacterial-based diseases. The targeted administration of nanoparticles can enhance the efficiency of conventional pharmaceutical agents. However, the interpretation of interfaces' interactions between nanoparticles and biological systems still remains a challenge for researchers. In fact, the current research presents a strategy for using ZnO NPs immobilization with ampicillin and tetracycline. Firstly, the study provides the mechanism of the ampicillin and tetracycline binding on the surface of ZnO NPs. Secondly, it examines the effect of non-immobilized ZnO NPs, immobilized with ampicillin (ZnONPs/AMP) and tetracycline (ZnONPs/TET), on the cells' metabolism and morphology, based on the protein and lipid profiles. A sorption kinetics study showed that the antibiotics binding on the surface of ZnONPs depend on their structure. The efficiency of the process was definitely higher in the case of ampicillin. In addition, flow cytometry results showed that immobilized nanoparticles present a different mechanism of action. Moreover, according to the MALDI approach, the antibacterial activity mechanism of the investigated ZnO complexes is mainly based on the destruction of cell membrane integrity by lipids and proteins, which is necessary for proper cell function. Additionally, it was noticed that some of the identified changes indicate the activation of defense mechanisms by cells, leading to a decrease in the permeability of a cell's external barriers or the synthesis of repair proteins.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Nanopartículas Metálicas/química , Nanocompostos/química , Zinco/química , Testes de Sensibilidade Microbiana/métodos , Óxido de Zinco/química
16.
BMC Womens Health ; 21(1): 235, 2021 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-34092217

RESUMO

BACKGROUND: The basic principle of vaginal laser therapy is the rejuvenation of the affected tissue. Zinc and copper are essential nutritional trace elements and have a key role in connective tissue homeostasis. We aimed to investigate the effect of vaginal, fractional CO2 laser treatment on cervicovaginal lavage (CVL) zinc and copper levels. METHODS: Twenty-nine postmenopausal women with symptoms of vaginal dryness were enrolled in our prospective cohort study. Three treatments with MonaLisa Touch CO2 laser system were performed four weeks apart. At each treatment CVL was collected, Vaginal Health Index (VHI) was obtained, and Visual Analog Scale (VAS) for vaginal dryness was assigned by patients. Zinc and copper concentrations were measured with optical emission spectrometry before each treatment and six weeks after the 3rd treatment. RESULTS: The VHI scores significantly improved after each laser treatment (mean ± SD VHI score, 13.03 ± 4.49 before vs. 15.55 ± 4.35 after the 1st, 17.79 ± 4.57 after the 2nd and 19.38 ± 4.39 after the 3rd treatment, P < 0.01). Similarly, VAS scores reflected improvement (mean ± SD VAS score 6.59 ± 2.86 before vs. 4.17 ± 2.86 after the 1st, 2.45 ± 2.43 after the 2nd and 1.41 ± 1.94 after the 3rd treatment, P < 0.01). CVL zinc levels were significantly higher compared to copper levels (0.06 ± 0.04 vs. 0.006 ± 0.006 mg/L, P < 0.01) at baseline. While copper levels remained the same through treatments, the CVL zinc level was significantly higher after the second laser treatment compared to the baseline. CONCLUSIONS: Fractional CO2 laser treatment of the vagina impacts CVL zinc and copper levels differently. While CVL copper levels were not different after each laser treatment, zinc levels were significantly higher after the second treatment before returning to baseline values.


Assuntos
Dióxido de Carbono , Cobre , Feminino , Humanos , Estudos Prospectivos , Irrigação Terapêutica , Resultado do Tratamento , Vagina/cirurgia , Zinco/uso terapêutico
17.
Environ Monit Assess ; 193(7): 430, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34151379

RESUMO

The assessment of the ecological status of natural surface water, in terms of dominant trace metals, within an area subject to various sources of pollution including a non-ferrous metal ore mining, such as the West Rhodope Mountain, Bulgaria, is significant. The present study estimates the ecological status of river body waters at industrial areas of the West Rhodope Mountain, Bulgaria, simultaneously evaluating the possibility of state forecasting, together with assessing the potential risks, through the study of scenarios focusing on (i) possible variations of physicochemical parameters such as pH, concentration levels of trace metals, sulphates, and dissolved organic carbon (DOC) of surface water and (ii) consideration of potential spontaneous precipitation reactions in the studied waters. The ecological status of river body waters was assessed through a combination of experimental field, laboratory, and computational techniques. Al, Mn, Zn, and Pb were found to be the dominant pollutants with a variety of chemical species and distribution. The most significant difference characterizing the chemical species distribution in light of total spontaneous crystallization in the systems was found for Pb, followed by Zn and Mn, with the differences being more significant at lower trace metal levels. The calculated species were discussed on the basis of HSAB (hard and soft acids and bases) principle.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Água Corporal/química , Bulgária , Catequina/análogos & derivados , Monitoramento Ambiental , Chumbo , Metais Pesados/análise , Rios , Poluentes Químicos da Água/análise , Zinco
18.
Anal Chem ; 93(23): 8257-8264, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34077178

RESUMO

Despite increased interest in microplasma-induced vapor generation (µPIVG) over the past several years, applications in real sample analyses remain limited due to their relatively low vapor generation efficiency and ambiguous mechanism. In this work, a novel method using methanol for significantly enhancing the liquid electrode discharge µPIVG efficiency was developed for the simultaneous and sensitive determination of Hg, Cd, and Zn by atomic fluorescence spectrometry (AFS). It is worth noting that the possible enhancement mechanism was investigated via the characterizations of volatile products by AFS, microplasma optical emission spectrometry, online gas chromatography, and gas chromatography-mass spectrometry, which involved the reductive species such as electrons, hydrogen radicals (·H), methyl radicals (·CH3), and other intermediates in the argon plasma adding methanol. Under the optimized conditions, the limits of detection of 0.007, 0.05, and 0.5 µg L-1 were obtained for Hg, Cd, and Zn, respectively, with relative standard deviations of 3.1, 3.7, and 5.2% for these elements, respectively. Vapor generation efficiencies of 90, 83, and 55% were achieved for Hg, Cd, and Zn, respectively, and improved 2.7-, 4.8-, and 7.9-fold, respectively, compared to those obtained in the absence of methanol. The accuracy and practicability of the proposed method were validated by the determination of Hg, Cd, and Zn in a certified reference material (CRM, Lobster hepatopancreas, TORT-3) and crayfish samples collected from three different provinces of China.


Assuntos
Cádmio , Mercúrio , Cádmio/análise , China , Eletrodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Mercúrio/análise , Metanol , Alta do Paciente , Zinco
19.
ACS Appl Mater Interfaces ; 13(26): 30317-30325, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34180223

RESUMO

Influenza A viruses (IAV) and SARS-CoV-2 can spread via liquid droplets and aerosols. Face masks and other personal protective equipment (PPE) can act as barriers that prevent the spread of these viruses. However, IAV and SARS-CoV-2 are stable for hours on various materials, which makes frequent and correct disposal of these PPE important. Metal ions embedded into PPE may inactivate respiratory viruses, but confounding factors such as adsorption of viruses make measuring and optimizing the inactivation characteristics difficult. Here, we used polyamide 6.6 (PA66) fibers containing embedded zinc ions and systematically investigated if these fibers can adsorb and inactivate SARS-CoV-2 and IAV H1N1 when woven into a fabric. We found that our PA66-based fabric decreased the IAV H1N1 and SARS-CoV-2 titer by approximately 100-fold. Moreover, we found that the zinc content and the virus inactivating property of the fabric remained stable over 50 standardized washes. Overall, these results provide insights into the development of reusable PPE that offer protection against RNA virus spread.


Assuntos
Vírus da Influenza A/fisiologia , Nylons/farmacologia , SARS-CoV-2/fisiologia , Têxteis , Inativação de Vírus/efeitos dos fármacos , Zinco/farmacologia , Adsorção , Animais , Chlorocebus aethiops , Fibra de Algodão , Cães , Células HEK293 , Humanos , Vírus da Influenza A/efeitos dos fármacos , Íons , Células Madin Darby de Rim Canino , Polipropilenos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Células Vero , Carga Viral , Óxido de Zinco/farmacologia
20.
Eur Rev Med Pharmacol Sci ; 25(10): 3772-3790, 2021 05.
Artigo em Inglês | MEDLINE | ID: covidwho-1264762

RESUMO

Multiple epidemiological studies have suggested that industrialization and progressive urbanization should be considered one of the main factors responsible for the rising of atherosclerosis in the developing world. In this scenario, the role of trace metals in the insurgence and progression of atherosclerosis has not been clarified yet. In this paper, the specific role of selected trace elements (magnesium, zinc, selenium, iron, copper, phosphorus, and calcium) is described by focusing on the atherosclerotic prevention and pathogenesis plaque. For each element, the following data are reported: daily intake, serum levels, intra/extracellular distribution, major roles in physiology, main effects of high and low levels, specific roles in atherosclerosis, possible interactions with other trace elements, and possible influences on plaque development. For each trace element, the correlations between its levels and clinical severity and outcome of COVID-19 are discussed. Moreover, the role of matrix metalloproteinases, a family of zinc-dependent endopeptidases, as a new medical therapeutical approach to atherosclerosis is discussed. Data suggest that trace element status may influence both atherosclerosis insurgence and plaque evolution toward a stable or an unstable status. However, significant variability in the action of these traces is evident: some - including magnesium, zinc, and selenium - may have a protective role, whereas others, including iron and copper, probably have a multi-faceted and more complex role in the pathogenesis of the atherosclerotic plaque. Finally, calcium and phosphorus are implicated in the calcification of atherosclerotic plaques and in the progression of the plaque toward rupture and severe clinical complications. In particular, the role of calcium is debated. Focusing on the COVID-19 pandemia, optimized magnesium and zinc levels are indicated as important protective tools against a severe clinical course of the disease, often related to the ability of SARS-CoV-2 to cause a systemic inflammatory response, able to transform a stable plaque into an unstable one, with severe clinical complications.


Assuntos
Aterosclerose/patologia , Oligoelementos/metabolismo , Aterosclerose/metabolismo , COVID-19/patologia , COVID-19/virologia , Cálcio/sangue , Cálcio/metabolismo , Cobre/sangue , Cobre/metabolismo , Humanos , Ferro/sangue , Ferro/metabolismo , Magnésio/sangue , Magnésio/metabolismo , Metaloproteinases da Matriz/metabolismo , Fósforo/sangue , Fósforo/metabolismo , Risco , SARS-CoV-2/isolamento & purificação , Selênio/sangue , Selênio/metabolismo , Índice de Gravidade de Doença , Oligoelementos/sangue , Zinco/sangue , Zinco/metabolismo
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