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1.
Nat Commun ; 11(1): 6110, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33257675

RESUMO

Water oxidation and concomitant dioxygen formation by the manganese-calcium cluster of oxygenic photosynthesis has shaped the biosphere, atmosphere, and geosphere. It has been hypothesized that at an early stage of evolution, before photosynthetic water oxidation became prominent, light-driven formation of manganese oxides from dissolved Mn(2+) ions may have played a key role in bioenergetics and possibly facilitated early geological manganese deposits. Here we report the biochemical evidence for the ability of photosystems to form extended manganese oxide particles. The photochemical redox processes in spinach photosystem-II particles devoid of the manganese-calcium cluster are tracked by visible-light and X-ray spectroscopy. Oxidation of dissolved manganese ions results in high-valent Mn(III,IV)-oxide nanoparticles of the birnessite type bound to photosystem II, with 50-100 manganese ions per photosystem. Having shown that even today's photosystem II can form birnessite-type oxide particles efficiently, we propose an evolutionary scenario, which involves manganese-oxide production by ancestral photosystems, later followed by down-sizing of protein-bound manganese-oxide nanoparticles to finally yield today's catalyst of photosynthetic water oxidation.


Assuntos
Luz , Compostos de Manganês/metabolismo , Manganês/metabolismo , Óxidos/metabolismo , Fotossíntese/fisiologia , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Complexo de Proteína do Fotossistema II/efeitos da radiação , 2,6-Dicloroindofenol , Atmosfera , Catálise , Evolução Molecular , Íons , Cinética , Modelos Moleculares , Oxirredução/efeitos da radiação , Oxigênio/química , Complexo de Proteína do Fotossistema II/química , Spinacia oleracea/metabolismo
2.
J Toxicol Sci ; 45(8): 411-422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32741894

RESUMO

Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in photoelectric and catalytic applications. However, their exposure and reproductive toxicity is unknown. In this study, the effect of the intragastric administration of two different-sized La2O3 particles in the testes of mice for 60 days was investigated. Although the body weight of mice treated or not treated with La2O3 NPs was not different and La2O3 NPs were distributed in the organs including the testis, liver, kidney, spleen, heart and brain. La2O3 NPs accumulate more than micro-sized La2O3 (MPs) in mice testes. The histopathological evaluation showed that moderate reproductive toxicity induced by La2O3 NPs in the testicle tissues. Furthermore, increased MDA, 8-OHdG levels and decreased SOD activities were detected in the La2O3 NP-treated groups. Moreover, qRT-PCR and western blotting data indicated that La2O3 NPs affecting the blood-testis barrier (BTB)-related genes in mice testes. Taken together, these findings suggested that La2O3 NPs activated inflammation responses and cross the BTB in the murine testes. This study provided useful information for risk analysis and regulation of La2O3 NPs by administrative agencies.


Assuntos
Lantânio/administração & dosagem , Lantânio/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos/administração & dosagem , Óxidos/toxicidade , Tamanho da Partícula , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Animais , Barreira Hematotesticular/metabolismo , Desoxiadenosinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação , Lantânio/metabolismo , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/administração & dosagem , Camundongos , Óxidos/metabolismo , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Distribuição Tecidual
3.
Int J Nanomedicine ; 15: 4607-4623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636621

RESUMO

Aim: The interaction of NPs with biological systems may reveal useful details about their pharmacodynamic, anticancer and antibacterial effects. Methods: Herein, the interaction of as-synthesized Co3O4 NPs with HSA was explored by different kinds of fluorescence and CD spectroscopic methods, as well as molecular docking studies. Also, the anticancer effect of Co3O4 NPs against leukemia K562 cells was investigated by MTT, LDH, caspase, real-time PCR, ROS, cell cycle, and apoptosis assays. Afterwards, the antibacterial effects of Co3O4 NPs against three pathogenic bacteria were disclosed by antibacterial assays. Results: Different characterization methods such as TEM, DLS, zeta potential and XRD studies proved that fabricated Co3O4 NPs by sol-gel method have a diameter of around 50 nm, hydrodynamic radius of 177 nm with a charge distribution of -33.04 mV and a well-defined crystalline phase. Intrinsic, extrinsic, and synchronous fluorescence as well as CD studies, respectively, showed that the HSA undergoes some fluorescence quenching, minor conformational changes, microenvironmental changes as well as no structural changes in the secondary structure, after interaction with Co3O4 NPs. Molecular docking results also verified that the spherical clusters with a dimension of 1.5 nm exhibit the most binding energy with HSA molecules. Anticancer assays demonstrated that Co3O4 NPs can selectively lead to the reduction of K562 cell viability through the cell membrane damage, activation of caspase-9, -8 and -3, elevation of Bax/Bcl-2 mRNA ratio, ROS production, cell cycle arrest, and apoptosis. Finally, antibacterial assays disclosed that Co3O4 NPs can stimulate a promising antibacterial effect against pathogenic bacteria. Conclusion: In general, these observations can provide useful information for the early stages of nanomaterial applications in therapeutic platforms.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Cobalto/química , Cobalto/farmacologia , Nanopartículas Metálicas/química , Óxidos/química , Óxidos/farmacologia , Albumina Sérica Humana/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobalto/metabolismo , Escherichia coli/efeitos dos fármacos , Humanos , Células K562 , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Óxidos/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Albumina Sérica Humana/química , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
4.
Nature ; 583(7816): 453-458, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669693

RESUMO

Manganese is one of the most abundant elements on Earth. The oxidation of manganese has long been theorized1-yet has not been demonstrated2-4-to fuel the growth of chemolithoautotrophic microorganisms. Here we refine an enrichment culture that exhibits exponential growth dependent on Mn(II) oxidation to a co-culture of two microbial species. Oxidation required viable bacteria at permissive temperatures, which resulted in the generation of small nodules of manganese oxide with which the cells associated. The majority member of the culture-which we designate 'Candidatus Manganitrophus noduliformans'-is affiliated to the phylum Nitrospirae (also known as Nitrospirota), but is distantly related to known species of Nitrospira and Leptospirillum. We isolated the minority member, a betaproteobacterium that does not oxidize Mn(II) alone, and designate it Ramlibacter lithotrophicus. Stable-isotope probing revealed 13CO2 fixation into cellular biomass that was dependent upon Mn(II) oxidation. Transcriptomic analysis revealed candidate pathways for coupling extracellular manganese oxidation to aerobic energy conservation and autotrophic CO2 fixation. These findings expand the known diversity of inorganic metabolisms that support life, and complete a biogeochemical energy cycle for manganese5,6 that may interface with other major global elemental cycles.


Assuntos
Bactérias/metabolismo , Crescimento Quimioautotrófico , Manganês/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Técnicas de Cocultura , Perfilação da Expressão Gênica , Isótopos , Manganês/química , Compostos de Manganês/química , Compostos de Manganês/metabolismo , Oxirredução , Óxidos/química , Óxidos/metabolismo , Filogenia
5.
J Med Chem ; 63(13): 7081-7107, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32479078

RESUMO

Phosphine oxides and related phosphorus-containing functional groups such as phosphonates and phosphinates are established structural motifs that are still underrepresented in today's drug discovery projects, and only few examples can be found among approved drugs. In this account, the physicochemical and in vitro properties of phosphine oxides and related phosphorus-containing functional groups are reported and compared to more commonly used structural motifs in drug discovery. Furthermore, the impact on the physicochemical properties of a real drug scaffold is exemplified by a series of phosphorus-containing analogs of imatinib. We demonstrate that phosphine oxides are highly polar functional groups leading to high solubility and metabolic stability but occasionally at the cost of reduced permeability. We conclude that phosphine oxides and related phosphorus-containing functional groups are valuable polar structural elements and that they deserve to be considered as a routine part of every medicinal chemist's toolbox.


Assuntos
Fenômenos Químicos , Desenho de Fármacos , Óxidos/química , Fosfinas/química , Células CACO-2 , Química Farmacêutica , Estabilidade de Medicamentos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Óxidos/metabolismo , Permeabilidade
6.
J Biosci Bioeng ; 130(4): 360-366, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32561073

RESUMO

Kokuto-shochu is a traditional Japanese spirit prepared from kokuto, a non-centrifugal brown cane sugar. When manufacturing kokuto, lime is added to the sugarcane juice to accelerate the crystallization of sucrose. Although the liming process differs depending on the manufacturer, the effects of liming on the quality of kokuto-shochu are unclear. Therefore, we investigated the flavor characteristics and volatiles present in kokuto-shochu prepared from kokuto with different liming degrees. Kokuto-shochu prepared from kokuto without liming had a pronounced kokuto-like flavor with a rich taste and contained higher contents of nerolidol, nonanal, acetoin, ß-damascenone, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone compared to that prepared from kokuto with liming. On the other hand, kokuto-shochu prepared from kokuto with excess liming had a comparative grassy flavor. It contained higher esters, 4-vinylguaiacol, and pyrazines compared to other shochu. The levels nerolidol, isoamyl acetate, nonanal, and acetoin were affected by the mash pH during fermentation, and thus, liming would affect the formation of such volatiles via changing the mash pH. In contrast, pyrazines, 4-vinylguaiacol, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were not affected by mash pH, and their levels in the kokuto-shochu were consistent with those in kokuto raw materials. These results suggested that the liming process affects the levels of volatiles in kokuto-shochu by changing the mash pH and volatile levels in kokuto raw materials.


Assuntos
Bebidas Alcoólicas/análise , Compostos de Cálcio/metabolismo , Óxidos/metabolismo , Açúcares/metabolismo , Paladar , Fermentação , Concentração de Íons de Hidrogênio
7.
Sci China Life Sci ; 63(8): 1168-1182, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32458255

RESUMO

Due to their many advantageous properties, nanomaterials (NMs) have been utilized in diverse consumer goods, industrial products, and for therapeutic purposes. This situation leads to a constant risk of exposure and uptake by the human body, which are highly dependent on nanomaterial size. Consequently, an improved understanding of the interactions between different sizes of nanomaterials and biological systems is needed to design safer and more clinically relevant nano systems. We discuss the sizedependent effects of nanomaterials in living organisms. Upon entry into biological systems, nanomaterials can translocate biological barriers, distribute to various tissues and elicit different toxic effects on organs, based on their size and location. The association of nanomaterial size with physiological structures within organs determines the site of accumulation of nanoparticles. In general, nanomaterials smaller than 20 nm tend to accumulate in the kidney while nanomaterials between 20 and 100 nm preferentially deposit in the liver. After accumulating in organs, nanomaterials can induce inflammation, damage structural integrity and ultimately result in organ dysfunction, which helps better understand the size-dependent dynamic processes and toxicity of nanomaterials in organisms. The enhanced permeability and retention effect of nanomaterials and the utility of this phenomenon in tumor therapy are also highlighted.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/química , Portadores de Fármacos/química , Nanopartículas/química , Animais , Antineoplásicos/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Transporte Biológico , Portadores de Fármacos/efeitos adversos , Humanos , Inflamação/induzido quimicamente , Rim/metabolismo , Cinética , Fígado/metabolismo , Pulmão/metabolismo , Metais/metabolismo , Nanopartículas/efeitos adversos , Óxidos/metabolismo , Tamanho da Partícula , Relação Estrutura-Atividade , Propriedades de Superfície , Distribuição Tecidual/efeitos dos fármacos
8.
Aquat Toxicol ; 224: 105498, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32402915

RESUMO

The current study focuses on the ecotoxicity of cobalt oxide nanoparticles (Co3O4 NPs) in the aquatic environment towards freshwater microalgae, Chlorella minutissima. The interaction of Co3O4 NPs with microalgae shows the growth suppressing effect. The 72 h EC 50 (effective concentration of a chemical having 50% of its impact) values of Co3O4 NPs for C. minutissima was 38.16 ± 1.99 mg/L. The decline in chlorophyll a content and increase in reactive oxygen species (ROS) also indicated the compromised physiological state of microalgae. An increased LDH (lactate dehydrogenase) level in treated samples suggests membrane disintegration by Co3O4 NPs. Light microscopy, scanning electron microscopy (SEM) and Energy Dispersive X-Ray-Scanning electron microscopy (EDX-SEM) further confirm cell entrapment and deposition of Co3O4 NPs on the cell surface. Cellular internalization of NPs, as shown by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), also contributes towards the toxicity of NPs. The findings suggest the role of extracellular as well as intracellular nanoparticles (NPs) in exerting a toxic effect on the C. minutissima.


Assuntos
Chlorella/efeitos dos fármacos , Cobalto/toxicidade , Água Doce/química , Nanopartículas Metálicas/toxicidade , Microalgas/efeitos dos fármacos , Óxidos/toxicidade , Poluentes Químicos da Água/toxicidade , Chlorella/metabolismo , Clorofila A/metabolismo , Cobalto/metabolismo , Microalgas/metabolismo , Microscopia Eletrônica de Varredura , Óxidos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/metabolismo
9.
Int J Nanomedicine ; 15: 1863-1870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231432

RESUMO

Background: Electronic devices which mimic the functionality of biological synapses are a large step to replicate the human brain for neuromorphic computing and for numerous medical research investigations. One of the representative synaptic behaviors is paired-pulse facilitation (PPF). It has been widely investigated because it is regarded to be related to biological memory. However, plasticity behavior is only part of the human brain memory behavior. Methods: Here, we present a phenomenon which is opposite to PPF, i.e., paired-pulse inhibition (PPI), in nano oxide devices for the first time. The research here suggests that rather than being enhanced, the phenomena of memory loss would also be possessed by such electronic devices. The device physics mechanism behind memory loss behavior was investigated. This mechanism is sustained by historical memory and degradation manufactured by device trauma to regulate characteristically stimulated origins of artificial transmission behaviors. Results: Under the trauma of a memory device, both the signal amplitude and signal time stimulated by a pulse are lower than the first signal stimulated by a previous pulse in the PPF, representing a new scenario in the struggle for memory. In this way, more typical human brain behaviors could be simulated, including the effect of age on latency and error generation, cerebellar infarct, trauma and memory loss pharmacological actions (such as those caused by hyoscines and nitrazepam). Conclusion: Thus, this study developed a new approach for implementing the manner in which the brain works in semiconductor devices for improving medical research.


Assuntos
Semicondutores , Sinapses/fisiologia , Biomimética , Encéfalo/fisiologia , Desenho de Equipamento , Nanoestruturas , Plasticidade Neuronal , Óxidos/metabolismo
10.
Chem Commun (Camb) ; 56(38): 5115-5118, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32319464

RESUMO

Graphdiyne (GDY) is a new recently-synthesized carbon allotrope. We find here that graphdiyne oxide (GDYO), the oxidized form of GDY, can serve as a new kind of carbon nanozyme mimicking peroxidase. This finding essentially offers a new platform for fundamental understanding of carbon nanozymes and broadens the application of GDY.


Assuntos
Carbono/metabolismo , Grafite/metabolismo , Nanoestruturas/química , Óxidos/metabolismo , Peroxidase/metabolismo , Carbono/química , Grafite/química , Óxidos/química , Tamanho da Partícula , Peroxidase/química , Propriedades de Superfície
11.
Drug Metab Pharmacokinet ; 35(3): 274-280, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32305264

RESUMO

Flavin containing monooxygenases (FMOs) represent one of the predominant types of phase I drug metabolizing enzymes (DMEs), and thus play an important role in the metabolism of xeno- and endobiotics for the generation of their corresponding oxides. These oxides often display biological activities, however they are difficult to study since their chemical or biological synthesis is generally challenging even though only small amounts are required to evaluate their efficacy and safety. Previously, we constructed a DME expression system for cytochrome P450, UDP-glucuronosyltransferase (UGT), and sulfotransferase (SULT) using yeast cells, and successfully produced xenobiotic metabolites in a whole-cell dependent manner. In this study, we developed a heterologous expression system for human FMOs, including FMO1-FMO5, in Saccharomyces cerevisiae and examined its N- and S-oxide productivity. The recombinant yeast cells expressed each of the FMO successfully, and the FMO4 transformant produced N- and S-oxide metabolites at several milligrams per liter within 24 h. This whole-cell dependent biosynthesis enabled the production of N- and S-oxides without the use of the expensive cofactor NADPH. Such novel yeast expression system could be a powerful tool for the production of oxide metabolites.


Assuntos
Óxidos/metabolismo , Oxigenases/metabolismo , Saccharomyces cerevisiae/metabolismo , Células Cultivadas , Humanos , Estrutura Molecular , Óxidos/química , Oxigenases/genética , Saccharomyces cerevisiae/citologia
12.
Int J Mol Sci ; 21(5)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131550

RESUMO

Manganese oxidizing bacteria can produce biogenic manganese oxides (BMO) on their cell surface and have been applied in the fields of agriculture, bioremediation, and drinking water treatment to remove toxic contaminants based on their remarkable chemical reactivity. Herein, we report for the first time the synthetic application of the manganese oxidizing bacteria, Pseudomonas putida MnB1 as a whole-cell biocatalyst for the effective oxidation of ß-keto ester with excellent yield. Differing from known chemical protocols toward this transformation that generally necessitate the use of organic solvents, stoichiometric oxygenating agents and complex chemical catalysts, our strategy can accomplish it simply under aqueous and mild conditions with higher efficiency than that provided by chemical manganese oxides. Moreover, the live MnB1 bacteria are capable of continuous catalysis for this C-O bond forming reaction for several cycles and remain proliferating, highlighting the favorable merits of this novel protocol for sustainable chemistry and green synthesis.


Assuntos
Proteínas de Bactérias/metabolismo , Biocatálise , Ésteres/metabolismo , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Oxirredutases/metabolismo , Pseudomonas putida/enzimologia , Microbiologia Industrial/métodos
13.
Anal Chim Acta ; 1105: 162-168, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32138915

RESUMO

Nanozymes, or nanomaterials that mimic the behaviors of enzymes, are highly promising materials for biomedical applications because of their excellent chemical stability under harsh conditions, simple preparation method and lower costs compared with natural enzymes. We herein report the intrinsic oxidase-mimicking activity of molybdenum oxide nanoparticles (MoO3 NPs). MoO3 NPs catalyzed the oxidation of colorless 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) to green product. The catalytic mechanism of the oxidase-mimicking activity of the MoO3 NPs was investigated in detail using electron spin resonance and a radical inhibition method. The oxidation of ABTS stems from 1O2 generated from the interaction between MoO3 NPs and dissolved oxygen in the solution. Acid phosphatase (ACP) catalyzes the hydrolysis of the ascorbic acid 2-phosphate (AAP) substrate to produce ascorbic acid (AA). AA was found to fade the coloration process of the MoO3 NP-mediated ABTS oxidation. By combining the oxidase-mimicking property of the MoO3 NPs and the ACP-catalyzed hydrolysis of AAP, a novel and simple colorimetric method for detecting ACP was established. The linear range for ACP determination is 0.09-7.3 U/L with a detection limit of 0.011 U/L. This new colorimetric method was successfully applied to the detection of ACP in diluted human serum samples and screening of ACP inhibitors. The present study proposes MoO3 NPs as a new oxidase mimic for establishing various biosensing method.


Assuntos
Fosfatase Ácida/análise , Técnicas Biossensoriais , Colorimetria , Molibdênio/química , Nanopartículas/química , Óxidos/química , Fosfatase Ácida/antagonistas & inibidores , Fosfatase Ácida/metabolismo , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Benzotiazóis/química , Benzotiazóis/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Molibdênio/metabolismo , Nanopartículas/metabolismo , Oxirredução , Óxidos/metabolismo , Tamanho da Partícula , Ácidos Sulfônicos/química , Ácidos Sulfônicos/metabolismo , Propriedades de Superfície
14.
Poult Sci ; 99(2): 1084-1087, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32029144

RESUMO

The objective of the current study was to evaluate increasing levels of manganese hydroxychloride (MHC) in 45-wk-old white leghorn laying hens, using yolk and shell manganese (Mn) content as a potential marker for Mn concentration. A total of 80, 45-wk-old white leghorns were assigned to 6 dietary treatments, each consisting of 14 individually caged laying hens, with the exception of the reference diet containing 10 individually caged laying hens. The experiment consisted of a reference diet that contained 70 ppm of supplemental inorganic Mn in the form of Mn oxide and 5 experimental treatments each containing 0, 15, 30, 60, and 90 ppm supplemental MHC. Experimental birds were subjected to a 21 D depletion phase in which no supplemental Mn was included in the diet; however, during this time reference fed birds were fed the control diet (70 ppm Mn). After the 21 D depletion phase, the depleted birds were fed experimental diets for a 35 D evaluation period. Yolk and shell Mn content were analyzed at the end of the depletion phase and during the experimental phase on day 5, 10, 15, 25, and 35. During the experimental phase, Mn was replenished in the yolk and shell in all experimental treatments containing supplemental Mn; however, dose and time impacted the rate of replenishment. The yolk tended to be more sensitive to variations in Mn level as increases in Mn inclusion significantly (P < 0.05) increased concentration. These data demonstrate the ability to deplete and replenish Mn, and the use of egg yolk Mn concentration as measurement for determining changes in dietary Mn. At the conclusion of the experiment at 35 D, 60 ppm of Mn hydroxychloride seemed to be adequate in replenishing Mn to the level of the reference.


Assuntos
Galinhas/metabolismo , Casca de Ovo/química , Gema de Ovo/química , Manganês/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Feminino , Manganês/administração & dosagem , Compostos de Manganês/administração & dosagem , Compostos de Manganês/metabolismo , Óxidos/administração & dosagem , Óxidos/metabolismo
15.
G Ital Nefrol ; 37(1)2020 Feb 12.
Artigo em Italiano | MEDLINE | ID: mdl-32068359

RESUMO

Primary hyperoxaluria (PH) is a rare genetic disorder with autosomal recessive transmission, characterized by high endogenous production and markedly excessive urinary excretion of oxalate (Ox). It causes the accumulation of calcium oxide crystals in organs and tissues including bones, heart, arteries, skin and kidneys, where it may cause oxalo-calcic nephrolithiasis, nephrocalcinosis and chronic renal failure. Some forms are secondary to enteric diseases, drugs or dietetic substances, while three primitive forms, caused by various enzymatic defects, are currently known: PH1, PH2 and PH3. An early diagnosis, with the aid of biochemical and genetic investigations, helps prevent complications and establish a therapeutic strategy that often includes liver and liver-kidney transplantation, improving the prognosis of these patients. In this work we describe the clinical case of a patient with PH1 undergoing extracorporeal hemodialysis treatment and we report the latest research results that could change the life of patients with PH.


Assuntos
Calciofilaxia/terapia , Hiperoxalúria Primária/genética , Hiperoxalúria Primária/terapia , Diálise Renal/métodos , Dermatopatias Metabólicas/terapia , Transaminases/genética , Calciofilaxia/etiologia , Calciofilaxia/patologia , Compostos de Cálcio/metabolismo , Feminino , Glioxilatos/metabolismo , Hemodiafiltração/métodos , Humanos , Hiperoxalúria Primária/diagnóstico , Falência Renal Crônica/etiologia , Transplante de Rim , Pessoa de Meia-Idade , Nefrocalcinose/etiologia , Nefrocalcinose/terapia , Uso Off-Label , Oxalatos/metabolismo , Óxidos/metabolismo , Dermatopatias Metabólicas/etiologia , Dermatopatias Metabólicas/patologia , Tiossulfatos/uso terapêutico
16.
ACS Nano ; 14(3): 3096-3120, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32105447

RESUMO

Lead oxide nanoparticles (PbONPs), upon their entry into the lungs via inhalation, induce structural changes in primary and secondary target organs. The fate and ultrastructural localization of PbONPs in organs is known to be dependent on the specific organ. Here, we focused on the differences in the ability to clear the inhaled PbONPs from secondary target organs and on molecular and cellular mechanisms contributing to nanoparticle removal. Mice were exposed to PbONPs in whole-body inhalation chambers. Clearance of ionic lead and PbONPs (Pb/PbONPs) from the lungs and liver was very effective, with the lead being almost completely eliminated from the lungs and the physiological state of the lung tissue conspicuously restored. Kidneys exposed to nanoparticles did not exhibit serious signs of damage; however, LA-ICP-MS uncovered a certain amount of lead located preferentially in the kidney cortex even after a clearance period. The concentration of lead in femurs, as representatives of the axial skeleton, was the highest among studied organs at all designated time points after PbONP exposure, and the clearance ability of lead from the femurs was very low in contrast to other organs. The organ-specific increase of ABC transporters expression (ABCG2 in lungs and ABCC3 in the liver) was observed in exposed animals, suggesting their involvement in removing Pb/PbONPs from tissues. Moreover, the expression of caveolins and clathrin displayed a tissue-specific response to lead exposure. Our results uncovered high variability among the organs in their ability to clear Pb/PbONPs and in the transporters involved in this process.


Assuntos
Chumbo/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Nanopartículas/metabolismo , Óxidos/metabolismo , Animais , Feminino , Chumbo/administração & dosagem , Chumbo/química , Fígado/química , Fígado/metabolismo , Pulmão/química , Pulmão/metabolismo , Proteínas de Membrana Transportadoras/química , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/administração & dosagem , Nanopartículas/química , Óxidos/administração & dosagem , Óxidos/química
17.
Colloids Surf B Biointerfaces ; 188: 110764, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31901687

RESUMO

Porous structures with highly dispersed and active catalytic sites are vital to improve the catalytic activity and stability of artificial enzyme-related catalytic reactions. Herein, a novel nanorod-like bimetal-organic framework serving as porous support and supplier of Co2+ and Cu2+ was used to prepare a beneficial porous metal oxide. By optimizing the calcination temperature, the composition of calcined product can be controlled and the nanorods with isolated and highly active CuCo2O4 nanoparticles were obtained. The porous CuCo2O4 nanorods exhibit a pH-dependent catalytic property, that is, they behave as oxidase in acid conditions and catalase in alkaline conditions. The CuCo2O4 nanorods perform dual-enzyme catalytic activity superior to monometallic oxides. What's more, compared with the reported Co3O4 nanoparticles, Co3O4/CuO hollow nanocage hybrids and NiCo2O4 mesoporous spheres, the porous CuCo2O4 nanorods show higher affinity to 3,3',5,5'-tetramethylbenzidine with a lower Km value. The superior dual-enzyme catalytic activities of CuCo2O4 nanorods benefit from the high catalytic activity of binary metal oxides and structural stability. After incubating in a wide range of pHs, temperatures and ionic strengths, the catalytic activity of CuCo2O4 nanorods can be maintained. The oxidase activity of CuCo2O4 nanorods can be inhibited in the presence of ascorbic acid, which can be applied in effective detection of ascorbic acid. This study opens a new path to prepare stable and highly active porous artificial enzymes.


Assuntos
Catalase/metabolismo , Cobalto/metabolismo , Cobre/metabolismo , Estruturas Metalorgânicas/metabolismo , Óxidos/metabolismo , Oxirredutases/metabolismo , Biocatálise , Catalase/química , Cobalto/química , Cobre/química , Estruturas Metalorgânicas/química , Nanotubos/química , Óxidos/química , Oxirredutases/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
18.
Biometals ; 33(1): 1-13, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31970541

RESUMO

Iron is critically important and highly regulated trace metal in the human body. However, in its free ion form, it is known to be cytotoxic; therefore, it is bound to iron storing protein, ferritin. Ferritin is a key regulator of body iron homeostasis able to form various types of minerals depending on the tissue environment. Each mineral, e.g. magnetite, maghemite, goethite, akaganeite or hematite, present in the ferritin core carry different characteristics possibly affecting cells in the tissue. In specific cases, it can lead to disease development. Widely studied connection with neurodegenerative conditions is widely studied, including Alzheimer disease. Although the exact ferritin structure and its distribution throughout a human body are still not fully known, many studies have attempted to elucidate the mechanisms involved in its regulation and pathogenesis. In this review, we try to summarize the iron uptake into the body. Next, we discuss the known occurrence of ferritin in human tissues. Lastly, we also examine the formation of iron oxides and their involvement in brain functions.


Assuntos
Encéfalo/metabolismo , Ferro/metabolismo , Doenças Neurodegenerativas/metabolismo , Óxidos/metabolismo , Ferritinas/metabolismo , Humanos , Doenças Neurodegenerativas/patologia
19.
Chemosphere ; 240: 124867, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542587

RESUMO

Phase transfer catalysts (PTCs) have been shown to be effective in lowering the limitation of mass transfer between aqueous oxidant MnO4- and NAPLs in in-situ chemical oxidation (ISCO) technologies for remediation of NAPLs. This work researched the effects of pentyltriphenylphosphonium bromide (PTPP, used as the representative PTC) for the enhancement of TCE oxidation, the extent of different treatment effects contributions and generalizability of phase transfer. Experimental results revealed that MnO4- exchanged with Br- in PTPP by ion exchange mechanism and then transferred to NAPL phase due to biphasic nature of PTPP-MnO4-. PTPP enhanced TCE dissolution in aqueous phase but had no significant effect on TCE solubilization. Enhanced TCE dissolution gradually weakened after 2.0 h and disappeared after 5.5 h, while the percentage of MnO4- in phase transfer was 14.8% at 7.5 h, which indicated that dissolution acceleration was only effective at initial stage of reaction (0-2.5 h). Therefore, persistent phase transfer process played the leading role in TCE remediation enhancement. Moreover, for different NAPL phase, more effective phase transfer could be achieved in NAPLs with higher solubility and weaker hydrophobicity. The best-fit polynomial relationship (R2 = 0.992) existed between the percentage amount of MnO4- transferred and the solubility of NAPL.


Assuntos
Compostos de Manganês/metabolismo , Óxidos/metabolismo , Poluentes Químicos da Água/química , Catálise , Poluentes Químicos da Água/análise
20.
Chemosphere ; 238: 124625, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31466008

RESUMO

The cyanotoxin cylindrospermopsin was discovered during a drinking water-related outbreak of human poisoning in 1979. Knowledge about the degradation of cylindrospermopsin in waterbodies is limited. So far, only few cylindrospermopsin-removing bacteria have been described. Manganese-oxidizing bacteria remove a variety of organic compounds. However, this has not been assessed for cyanotoxins yet. We investigated cylindrospermopsin removal by manganese-oxidizing bacteria, isolated from natural and technical systems. Cylindrospermopsin removal was evaluated under different conditions. We analysed the correlation between the amount of oxidized manganese and the cylindrospermopsin removal, as well as the removal of cylindrospermopsin by sterile biogenic oxides. Removal rates in the range of 0.4-37.0 µg L-1 day-1 were observed. When MnCO3 was in the media Pseudomonas sp. OF001 removed ∼100% of cylindrospermopsin in 3 days, Comamonadaceae bacterium A210 removed ∼100% within 14 days, and Ideonella sp. A288 and A226 removed 65% and 80% within 28 days, respectively. In the absence of Mn2+, strain A288 did not remove cylindrospermopsin, while the other strains removed 5-16%. The amount of manganese oxidized by the strains during the experiment did not correlate with the amount of cylindrospermopsin removed. However, the mere oxidation of Mn2+ was indispensable for cylindrospermopsin removal. Cylindrospermopsin removal ranging from 0 to 24% by sterile biogenic oxides was observed. Considering the efficient removal of cylindrospermopsin by the tested strains, manganese-oxidizing bacteria might play an important role in cylindrospermopsin removal in the environment. Besides, manganese-oxidizing bacteria could be promising candidates for biotechnological applications for cylindrospermopsin removal in water treatment plants.


Assuntos
Toxinas Bacterianas/análise , Burkholderiales/metabolismo , Comamonadaceae/metabolismo , Manganês/metabolismo , Pseudomonas/metabolismo , Uracila/análogos & derivados , Purificação da Água/métodos , Alcaloides , Água Potável/metabolismo , Compostos de Manganês/metabolismo , Oxirredução , Óxidos/metabolismo , Uracila/análise
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