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1.
Int J Biol Macromol ; 278(Pt 1): 134654, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128748

RESUMO

In this paper the effects on the interaction of highly positively charged substitution-inert platinum polynuclear complexes (SI-PPCs) with negatively charged DNA and heparin are examined and compared by theoretical chemistry methods. Electrostatic and hydrogen bonding interactions contribute to the overall effects on the biomolecule. Root Mean Square (RMS) deviation, Solvent Accessible Surface, RMS fluctuation, and interaction analysis all confirm similar effects on both biomolecules, dictated predominantly by the total positive charge and total number of hydrogen bonds formed. Especially, changes in structural parameters suggesting condensation and reduction of available surface area will reduce or prevent normal protein recognition and may thus potentially inhibit biological mechanisms related to apoptosis (DNA) or reduced vascularization viability (HEP). Thermodynamic analyses supported these findings with favourable interaction energies. The comparison of DNA and heparin confirms the general intersectionality between the two biomolecules and confirms the intrinsic dual-nature function of this chemotype. The distinction between the two-limiting mode of actions (HS or DNA-centred) could reflect an intriguing balance between extracellular (GAG) and intracellular (DNA) binding and affinities. The results underline the need to fully understand GAG-small molecule interactions and their contribution to drug pharmacology and related therapeutic modalities. This report contributes to that understanding.


Assuntos
DNA , Simulação de Dinâmica Molecular , Espermidina , Espermina , Espermina/química , DNA/química , DNA/metabolismo , Espermidina/química , Espermidina/metabolismo , Heparina/química , Heparina/metabolismo , Termodinâmica , Ligação de Hidrogênio , Eletricidade Estática
2.
Environ Pollut ; 358: 124485, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960115

RESUMO

New mixtures of pesticides are being placed on the market to increase the spectrum of phytosanitary action. Thus, the eco(geno)toxic effects of the new commercial mixture named Platinum Neo, as well as its constituents the neonicotinoid Thiamethoxam and the pyrethroid Lambda-Cyhalothrin, were investigated using the species Daphnia magna, Raphidocelis subcapitata, Danio rerio, and Allium cepa L. The lowest- and no-observed effect concentration (LOEC and NOEC) were measured in ecotoxicological tests. While Thiamethoxam was ecotoxic at ppm level, Lambda-Cyhalothrin and Platinum Neo formulation were ecotoxic at ppb level. The mitotic index (MI), chromosomal aberrations and micronucleus [MN] frequency were measured as indicators of phytogenotoxicity in A. cepa plants exposed for 12 h to the different insecticides and their mixture under different dilutions. There were significant alterations in the MI and MN frequency in comparison with the A. cepa negative control group, with Thiamethoxam, Lambda-Cyhalothrin, and Platinum Neo treatments all significantly reducing MI and increasing MN frequency. Thus, MI reduction was found at 13.7 mg L-1 for Thiamethoxam, 0.8 µg L-1 for Lambda-Cyahalothrin, and 2.7:2 µg L-1 for Platinum Neo, while MN induction was not observed at 14 mg L-1 for Thiamethoxam, 0.8 µg L-1 for Lambda-Cyahalothrin, and 1.4:1 µg L-1 for Platinum Neo. The insecticide eco(geno)toxicity hierarchy was Platinun Neo > Lambda-Cyhalothrin > Thiamethoxam, and the organism sensitivity hierarchy was daphnids > fish > algae > A. cepa. Eco(geno)toxicity studies of new pesticide mixtures can be useful for management, risk assessment, and avoiding impacts of these products on living beings.


Assuntos
Daphnia , Inseticidas , Nitrilas , Cebolas , Piretrinas , Tiametoxam , Piretrinas/toxicidade , Tiametoxam/toxicidade , Animais , Inseticidas/toxicidade , Nitrilas/toxicidade , Cebolas/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Neonicotinoides/toxicidade , Peixe-Zebra , Tiazóis/toxicidade , Oxazinas/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Nitrocompostos/toxicidade , Testes para Micronúcleos
3.
Chemphyschem ; 25(16): e202400359, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38721776

RESUMO

The interaction between organic molecules and oxidized catalyst surfaces has frequently been used to study the fuel crossover from the anode to the cathode in direct liquid fuel cells. In such experiments, the oxidized surface is put in contact with the fuel under open circuit conditions, and the evolution of the potential is registered. The open circuit potential (OCP) vs. time features can then inform on the reactivity of the fuel with the oxidized surface and provide valuable information not only to applications in fuel cells but also to the electrochemical reform of those molecules to produce clean hydrogen. In this paper, we present an experimental investigation of the open circuit interaction between ethanol or 2-propanol with oxidized platinum surfaces. Besides the OCP time traces, we have also employed cyclic voltammetry and fast oxide reduction sweep in the presence of the alcohols. Comparable reaction currents are obtained in the cyclic voltammogram, but the electro-oxidation of 2-propanol sets in at considerably lower overpotentials than that of ethanol. At the high potential region, both the magnitude and the potential of the current peak are nearly identical in both cases. In contrast, under open circuit conditions, the interaction of ethanol with the oxidized platinum surface is more pronounced than that found for 2-propanol, and these results are corroborated by the facile reduction of the platinum oxides along the fast backward sweep for the case of the latter.

4.
Nanomaterials (Basel) ; 14(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38668187

RESUMO

This study focuses on the synthesis of mixed metal oxide anodes (MMOs) with the composition Ti/RuO2Sb2O4Ptx (where x = 0, 5, 10 mol) using hybrid microwave irradiation heating. The synthesized electrodes were characterized using scanning electron microscopy, X-ray energy-dispersive analysis, X-ray diffraction, cyclic voltammetry, and electrochemical impedance spectroscopy. These electrodes were then evaluated in both bulk electrolytic and fuel cell tests within a reversible chloralkaline electrochemical cell. The configurations using the electrodes Ti/(RuO2)0.7-(Sb2O4)0.3 and Ti/(RuO2)66.5-(Sb2O4)28.5-Pt5 presented lower onset potential for oxygen and chlorine evolution reactions and reduced resistance to charge transfer compared to the Ti/(RuO2)63-(Sb2O4)27-Pt10 variant. These electrodes demonstrated notable performance in reversible electrochemical cells, achieving Coulombic efficiencies of up to 60% when operating in the electrolytic mode at current densities of 150 mA cm-2. They also reached maximum power densities of 1.2 mW cm-2 in the fuel cell. In both scenarios, the presence of platinum in the MMO coating positively influenced the process. Furthermore, a significant challenge encountered was crossover through the membranes, primarily associated with gaseous Cl2. This study advances our understanding of reversible electrochemical cells and presents possibilities for further exploration and refinement. It demonstrated that the synergy of innovative electrode synthesis strategies and electrochemical engineering can lead to promising and sustainable technologies for energy conversion.

5.
Front Nephrol ; 4: 1384208, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666245

RESUMO

Acquired tubulopathies are frequently underdiagnosed. They can be characterized by the renal loss of specific electrolytes or organic solutes, suggesting the location of dysfunction. These tubulopathies phenotypically can resemble Bartter or Gitelman syndrome). These syndromes are infrequent, they may present salt loss resembling the effect of thiazides (Gitelman) or loop diuretics (Bartter). They are characterized by potentially severe hypokalemia, associated with metabolic alkalosis, secondary hyperaldosteronism, and often hypomagnesemia. Tubular dysfunction has been described as nephrotoxic effects of platinum-based chemotherapy. We present 4 cases with biochemical signs of tubular dysfunction (Bartter-like/Gitelman-like phenotype) related to chemotherapy.

6.
J Histochem Cytochem ; 72(3): 173-188, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38439738

RESUMO

Cisplatin (cPt) is a commonly used treatment for solid tumors. The main target of its cytotoxicity is the DNA molecule, which makes the DNA damage response (DDR) crucial for cPt-based chemotherapy. Therefore, it is essential to identify biomarkers that can accurately predict the individual clinical response and prognosis. Our goal was to assess the usefulness of alkaline comet assay and immunocytochemical staining of phosphorylated Hsp90α (p-Hsp90α), γH2AX, and 53BP1 as predictive/prognostic markers. Pre-chemotherapy peripheral blood leukocytes were exposed to cPt in vitro and collected at 0, 24 (T24), and 48 (T48) hr post-drug removal. Healthy subjects were also included. Baseline DNA damage was elevated in cancer patients (variability between individuals was observed). After cPt, patients showed increased γH2AX foci/nucleus (T24 and T48). Both in healthy persons and patients, the nuclear p-Hsp90α and N/C (nuclear/cytoplasmic) ratio augmented (T24), decreasing at T48. Favorable clinical response was associated with high DNA damage and p-Hsp90α N/C ratio following cPt. For the first time, p-Hsp90α significance as a predictive marker is highlighted. Post-cPt-DNA damage was associated with longer disease-free survival and overall survival. Our findings indicate that comet assay and p-Hsp90α (a marker of DDR) would be promising prognostic/predictive tools in cP-treated cancer patients.


Assuntos
Cisplatino , Neoplasias , Humanos , Ensaio Cometa , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Dano ao DNA , Leucócitos
7.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474580

RESUMO

Most diseases that affect human beings across the world are now treated with drugs of organic origin. However, some of these are associated with side effects, toxicity, and resistance phenomena. For the treatment of many illnesses, the development of new molecules with pharmacological potential is now an urgent matter. The biological activities of metal complexes have been reported to have antitumor, antimicrobial, anti-inflammatory, anti-infective and antiparasitic effects, amongst others. Metal complexes are effective because they possess unique properties. For example, the complex entity possesses the effective biological activity, then the formation of coordination bonds between the metal ions and ligands is controlled, metal ions provide it with extraordinary mechanisms of action because of characteristics such as d-orbitals, oxidation states, and specific orientations; metal complexes also exhibit good stability and good physicochemical properties such as water solubility. Platinum is a transition metal widely used in the design of drugs with antineoplastic activities; however, platinum is associated with side effects which have made it necessary to search for, and design, novel complexes based on other metals. Copper is a biometal which is found in living systems; it is now used in the design of metal complexes with biological activities that have demonstrated antitumoral, antimicrobial and anti-inflammatory effects, amongst others. In this review, we consider the open horizons of Cu(II)- and Pt(II)-based complexes, new trends in their design, their synthesis, their biological activities and their targets of action.


Assuntos
Anti-Infecciosos , Antineoplásicos , Complexos de Coordenação , Humanos , Cobre/química , Complexos de Coordenação/química , Platina/química , Antineoplásicos/farmacologia , Anti-Infecciosos/farmacologia , Íons , Anti-Inflamatórios , Ligantes
8.
J Trace Elem Med Biol ; 83: 127374, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38266419

RESUMO

BACKGROUND: In the search for alternatives that attenuate the toxicity associated to oncologic treatment with cisplatin (CDDP) and considering the potential health-beneficial properties of exopolysaccharides (EPS) produced by lactic acid bacteria, it was aimed on this study to evaluate the cytotoxic, toxicologic and antitumoral efficacy of a bioconjugate based on CDDP and EPS, on the experimental tumor of sarcoma 180. METHODS: After the synthesis of the cis-[Pt(NH3)2(Cl)2] complex and of the conjugate containing Lactobacillus fermentum exopolysaccharide was tested both in vitro and in vivo for evaluating the acute toxicity. RESULTS: The antitumoral study was performed using mice transplanted with sarcoma 180. The bioconjugate showed low to medium cytotoxicity for the cell lines tested, as well moderated acute toxicity. After determining the LD50, the following experimental groups were established for the antitumor assay: Control (NaCl 0,9%), CDDP (1 mg/kg), EPS and bioconjugate composition (200 mg/kg). The bioconjugate promoted a 38% regression in tumor mass when compared to the control, and a regression of 41% when compared to CDDP. Liver histopathological analysis revealed discrete alterations in animals treated with (CDDP + EPS) when compared to control. The bioconjugate also minimized changes in the renal parenchyma resulting from the tumor. CONCLUSION: Our results indicate that when CDDP is associated with EPS, this composition was more biocompatible, showing itself as a potent chemotherapeutic agent and lower tissue toxicity.


Assuntos
Antineoplásicos , Neoplasias , Sarcoma 180 , Camundongos , Animais , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Sarcoma 180/tratamento farmacológico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico
9.
Clin Otolaryngol ; 49(1): 1-15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37818931

RESUMO

OBJECTIVES: Ototoxicity is a common disabling side effect of platinum-based chemotherapy. This study aimed to assess the evidence on the management of platinum-induced ototoxicity in adult cancer patients. METHODS: Four databases were searched up to 1 November 2022. Original studies were included if they reported on a pharmacologic or non-pharmacologic intervention to prevent or treat platinum ototoxicity in adults. The articles' quality was assessed via two grading scales. RESULTS: Nineteen randomised controlled trials and five quasi-experimental studies with 1673 patients were analysed. Eleven interventions were identified, nine pharmacological and two non-pharmacological. Six of the interventions (sodium thiosulphate, corticoids, sertraline, statins, multivitamins and D-methionine) showed mild benefits in preventing cisplatin-induced ototoxicity. Only one trial assessed corticoids as a potential treatment. Overall, only six trials were deemed with a low risk of bias. The majority of studies inadequately documented intervention-related adverse effects, thereby limiting safety conclusions. CONCLUSIONS: Current interventions have mild benefits in preventing cisplatin-induced ototoxicity in adult cancer patients. Sodium thiosulphate is the most promising intervention as a preventive strategy. Rigorous, high-quality research is warranted, encompassing an evaluation of all potential symptoms and innovative treatment modalities.


Assuntos
Antineoplásicos , Perda Auditiva , Neoplasias , Ototoxicidade , Adulto , Humanos , Cisplatino/uso terapêutico , Antineoplásicos/uso terapêutico , Carboplatina/efeitos adversos , Ototoxicidade/etiologia , Ototoxicidade/prevenção & controle , Ototoxicidade/tratamento farmacológico , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , Perda Auditiva/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias/induzido quimicamente , Corticosteroides/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Braz J Microbiol ; 55(1): 11-24, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38051456

RESUMO

In this manuscript, we report the photo-inactivation evaluation of new tetra-cationic porphyrins with peripheral Pt(II) complexes ate meta N-pyridyl positions in the antimicrobial photodynamic therapy (aPDT) of rapidly growing mycobacterial strains (RGM). Four different metalloderivatives were synthetized and applied. aPDT experiments in the strains of Mycobacteroides abscessus subsp. Abscessus (ATCC 19977), Mycolicibacterium fortuitum (ATCC 6841), Mycobacteroides abscessus subsp. Massiliense (ATCC 48898), and Mycolicibacterium smegmatis (ATCC 700084) conducted with adequate concentration of photosensitizers (PS) under white-light conditions at 90 min (irradiance of 50 mW cm-2 and a total light dosage of 270 J cm-2) showed that the Zn(II) derivative is the most effective PS significantly reduced the concentration of viable mycobacteria. The effectiveness of the molecule as PS for PDI studies is also clear with mycobacteria, which is strongly related with the porphyrin peripheral charge and coordination platinum(II) compounds and consequently about the presence of metal center ion. This class of PS may be promising antimycobacterial aPDT agents with potential applications in medical clinical cases and bioremediation.


Assuntos
Mycobacterium , Porfirinas , Platina/farmacologia , Luz , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Antibacterianos
11.
Chembiochem ; 25(6): e202300696, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38146865

RESUMO

Pt(II) and Pd(II) coordinating N-donor ligands have been extensively studied as anticancer agents after the success of cisplatin. In this work, a novel bidentate N-donor ligand, the N-[[4-(phenylmethoxy)phenyl]methyl]-2-pyridinemethanamine, was designed to explore the antiparasitic, antiviral and antitumor activity of its Pt(II) and Pd(II) complexes. Chemical and spectroscopic characterization confirm the formation of [MLCl2 ] complexes, where M=Pt(II) and Pd(II). Single crystal X-ray diffraction confirmed a square-planar geometry for the Pd(II) complex. Spectroscopic characterization of the Pt(II) complex suggests a similar structure. 1 H NMR, 195 Pt NMR and HR-ESI-MS(+) analysis of DMSO solution of complexes indicated that both compounds exchange the chloride trans to the pyridine for a solvent molecule with different reaction rates. The ligand and the two complexes were tested for in vitro antitumoral, antileishmanial, and antiviral activity. The Pt(II) complex resulted in a GI50 of 10.5 µM against the NCI/ADR-RES (multidrug-resistant ovarian carcinoma) cell line. The ligand and the Pd(II) complex showed good anti-SARS-CoV-2 activity with around 65 % reduction in viral replication at a concentration of 50 µM.


Assuntos
Antineoplásicos , Complexos de Coordenação , Platina/farmacologia , Platina/química , Ligantes , Cisplatino , Antineoplásicos/farmacologia , Antineoplásicos/química , Antivirais/farmacologia , Paládio/farmacologia , Paládio/química , Cristalografia por Raios X , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Linhagem Celular Tumoral
12.
J Biol Inorg Chem ; 28(8): 711-723, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768364

RESUMO

In this work, two analogous coumarin-thio and semicarbazone hybrid compounds were prepared and evaluated as a potential antichagasic agents. Furthermore, palladium and platinum complexes with the thiosemicarbazone derivative as ligand (L1) were obtained in order to establish the effect of metal complexation on the antiparasitic activity. All compounds were fully characterized both in solution and in solid state including the resolution of the crystal structure of the palladium complex by X-ray diffraction methods. Unexpectedly, all experimental and theoretical characterizations in the solid state, demonstrated that the obtained palladium and platinum complexes are structurally different: [PdCl(L1)] and [PtCl2(HL1)]. All the studied compounds lower the proliferation of the amastigote form of Trypanosoma cruzi while some of them also have an effect on the trypomastigote stage. Additionally, the compounds inhibit T. cruzi release from host cells in variable extents. The Pd compound presented a remarkable profile in all the in vitro experiments, and it showed no toxicity for mammalian cells in the assayed concentrations. In this sense, in vivo experiments were performed for this compound using an acute model of Chagas disease. Results showed that the complex significantly lowered the parasite count in the mice blood with no significant toxicity.


Assuntos
Tiossemicarbazonas , Tripanossomicidas , Trypanosoma cruzi , Animais , Camundongos , Paládio/farmacologia , Paládio/química , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Ligantes , Parasitemia , Platina/química , Tripanossomicidas/farmacologia , Cumarínicos/farmacologia , Mamíferos
13.
Biosensors (Basel) ; 13(9)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37754112

RESUMO

Liposomes are prominent nanosystems for drug delivery, with potential extending beyond isolated drugs. Ethanol-aqueous plant extracts can be encapsulated within liposomes to protect bioactive compounds (secondary metabolites) from rapid oxidation and enable sustained release. Determining which compound classes are present in each extract and the encapsulation efficiency (EE) of these extracts in liposomes is crucial for nanocarrier functionality. This involves assessing the ratio of bioactive substances within liposomes to the total content. However, quantifying EE for non-isolated compounds poses challenges due to the need for advanced analytical equipment and biosensing approaches. This study introduces an innovative method for EE quantification, using a conductivity electrode (k = 0.842/cm) to establish an EE biosensing technology. By correlating dynamic light scattering (DLS), zeta potential (ZP), and electrical conductivity (Cnd) data with the conductivity meter's calibration curve, a robust relationship between the free extract concentration and Cnd (r2 ≥ 0.950) was established. Lavender-loaded liposomes demonstrated an EE of 56.33%, while wormwood and oregano formulations exhibited high EEs of 94.33% and 91.70%, respectively. In contrast, sage-loaded liposomes exhibited an inadequate EE, encapsulating only approximately 0.57% of the extract. The straightforward quantification of the free extract within liposome formulations, compared to more complex approaches, could facilitate EE determination and support future characterizations.


Assuntos
Sistemas de Liberação de Medicamentos , Lipossomos , Calibragem , Cor , Condutividade Elétrica
14.
J Mol Graph Model ; 125: 108621, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37689026

RESUMO

The comprehension of the factors affecting the adsorption of ethanol over metals and metal alloys is a crucial step for the rational development of new catalysts for hydrogen production through ethanol reforming. In this work, we analyze the effect of combining Pt and Sn on a metal cluster on the complexation energy and reactivity for OH dehydrogenation of ethanol. Metal clusters of Pt10, Sn10 and Pt5Sn5 had their putative minimum located with the help of the artificial bee colony algorithm. Whereas the isolated Pt cluster shows a high degree of polarization (ESP surface), the Sn cluster shows a quite uniform electron density surface. The PtSn cluster is strongly polarized, with Pt atoms withdrawing electron density of Sn atoms. Complexation occurs with the oxygen atom of ethanol directed towards the point of highest electron potential in the ESP surface. Pt presents the highest complexation energy, -20.90 kcal/mol, against only -7.83 kcal/mol (at the B97-3c level). For the PtSn cluster, the value is intermediate, namely -12.39 kcal/mol. The more malleable electron density of Pt and its electron affinity are responsible for its highest complexation energy. These characteristics are partially transferred to the PtSn cluster. QTAIM results show that, for the PtSn cluster, the O-H bond in ethanol is somewhat weaker than for pure Pt and Sn. As a consequence, the energy barrier for the O-H dehydrogenation has its lowest value for the PtSn cluster, which shows that the alloying of two metals can lead to quite quite unexpected results opening the perspective for a more rational fine tuning of catalysts properties.


Assuntos
Algoritmos , Ligas , Adsorção , Elétrons , Etanol
15.
Pharmaceutics ; 15(3)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36986881

RESUMO

Colorectal cancer is occasionally called colon or rectal cancer, depending on where cancer begins to form, and is the second leading cause of cancer death among both men and women. The platinum-based [PtCl(8-O-quinolinate)(dmso)] (8-QO-Pt) compound has demonstrated encouraging anticancer activity. Three different systems of 8-QO-Pt-encapsulated nanostructured lipid carriers (NLCs) with riboflavin (RFV) were investigated. NLCs of myristyl myristate were synthesized by ultrasonication in the presence of RFV. RFV-decorated nanoparticles displayed a spherical shape and a narrow size dispersion in the range of 144-175 nm mean particle diameter. The 8-QO-Pt-loaded formulations of NLC/RFV with more than 70% encapsulation efficiency showed sustained in vitro release for 24 h. Cytotoxicity, cell uptake, and apoptosis were evaluated in the HT-29 human colorectal adenocarcinoma cell line. The results revealed that 8-QO-Pt-loaded formulations of NLC/RFV showed higher cytotoxicity than the free 8-QO-Pt compound at 5.0 µM. All three systems exhibited different levels of cellular internalization. Moreover, the hemotoxicity assay showed the safety profile of the formulations (less than 3.7%). Taken together, RFV-targeted NLC systems for drug delivery have been investigated for the first time in our study and the results are promising for the future of chemotherapy in colon cancer treatment.

16.
Acta Otolaryngol ; 143(3): 242-249, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36943799

RESUMO

BACKGROUND: Cisplatin appears to enter the cochlear cells through the organic cation transporter 2 (OCT2). There is recent evidence that multidrug and toxin extrusion protein 1 (MATE1) is involved in cisplatin-induced nephrotoxicity. Its presence and role in the ear are unknown. AIMS/OBJECTIVES: Evaluate the presence and localization of MATE1, and determine the localization of OCT2, in the cochlea. Evaluate cisplatin uptake with regard to MATE1 and OCT2 expression. MATERIAL AND METHODS: Murine cochlear explants and paraffin-embedded cochleae were evaluated with immunohistochemistry for OCT2 and MATE1. Explant cultures were also treated with Texas Red cisplatin to determine their cellular uptake. RESULTS: MATE1 is present in the cochlea. Most intense labeling of MATE1 and OCT2 was seen in the outer hair cells (OHCs) and pillar cells, respectively. Both transporters were observed in the spiral ganglion neurons and stria vascularis. Expression levels of OCT2 and MATE1 decreased following cisplatin exposure. Texas Red cisplatin staining was strong in OHCs and pillar cells. CONCLUSIONS AND SIGNIFICANCE: To the best of our knowledge, this is the first study demonstrating the presence and localization of MATE1 in the cochlea. OCT2 labeling was seen in pillar cells. Consistently, OHCs and pillar cells uptake Texas Red cisplatin.


Assuntos
Cisplatino , Ototoxicidade , Camundongos , Animais , Cisplatino/toxicidade , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Cóclea/metabolismo
17.
Biosensors (Basel) ; 13(2)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36831956

RESUMO

The demand for new devices that enable the detection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) at a relatively low cost and that are fast and feasible to be used as point-of-care is required overtime on a large scale. In this sense, the use of sustainable materials, for example, the bio-based poly (ethylene terephthalate) (Bio-PET) can be an alternative to current standard diagnostics. In this work, we present a flexible disposable printed electrode based on a platinum thin film on Bio-PET as a substrate for the development of a sensor and immunosensor for the monitoring of COVID-19 biomarkers, by the detection of L-cysteine and the SARS-CoV-2 spike protein, respectively. The electrode was applied in conjunction with 3D printing technology to generate a portable and easy-to-analyze device with a low sample volume. For the L-cysteine determination, chronoamperometry was used, which achieved two linear dynamic ranges (LDR) of 3.98-39.0 µmol L-1 and 39.0-145 µmol L-1, and a limit of detection (LOD) of 0.70 µmol L-1. The detection of the SARS-CoV-2 spike protein was achieved by both square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) by a label-free immunosensor, using potassium ferro-ferricyanide solution as the electrochemical probe. An LDR of 0.70-7.0 and 1.0-30 pmol L-1, with an LOD of 0.70 and 1.0 pmol L-1 were obtained by SWV and EIS, respectively. As a proof of concept, the immunosensor was successfully applied for the detection of the SARS-CoV-2 spike protein in enriched synthetic saliva samples, which demonstrates the potential of using the proposed sensor as an alternative platform for the diagnosis of COVID-19 in the future.


Assuntos
Técnicas Biossensoriais , COVID-19 , Humanos , SARS-CoV-2 , Platina , Técnicas Biossensoriais/métodos , Cisteína , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos
18.
Circ Res ; 132(4): 481-482, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36795848
19.
J Inorg Biochem ; 242: 112149, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36780772

RESUMO

We report the synthesis and characterization of new tri-cationic corrole derivatives, containing Pt(II) or Pd(II) complexes attached at the peripheral position of thienyl moieties. Corrole derivatives were characterized through microanalysis, electrochemical, spectrometry and spectroscopy analysis. Singlet and triplet excited-states are investigated by photophysical/theoretical calculation methods and photobiological parameters were also evaluated spectroscopic techniques (UV-Vis and EPR). Also, the binding capacity of each corrole derivative with nucleic acids (DNA) and human serum albumin (HSA) was determined by UV-Vis, steady-state, and time-resolved fluorescence spectroscopy, combined with molecular docking analysis. Moreover, the new corroles containing peripheral complexes improve their interactions with biomacromolecules, generate reactive oxygen species under light source irradiation studied and has potential for application in photodynamic therapeutic processes.


Assuntos
Porfirinas , Humanos , Simulação de Acoplamento Molecular , Porfirinas/química , Espectrometria de Fluorescência
20.
Clin Transl Oncol ; 25(5): 1340-1352, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36527574

RESUMO

PURPOSE: The poor prognosis of ovarian cancer is largely due to platinum resistance. It has been demonstrated that nucleotide excision repair (NER) involving centrin-2(CETN2) is connected to platinum resistance in ovarian cancer. The molecular mechanism of CETN2 in ovarian cancer and the mechanism affecting the outcome of chemotherapy are unknown. METHODS: The protein-protein interaction (PPI) network was mapped after obtaining the interacting proteins of CETN2, and the interacting genes were subjected to enrichment analysis. To examine the relationship between CETN2 and platinum resistance, gene microarray data and clinical data related to platinum resistance in ovarian cancer were downloaded. The possible signaling pathway of CETN2 was investigated by Gene set enrichment analysis (GSEA). Immune infiltration analysis was performed. Immunohistochemistry (IHC) and quantitative real-time PCR (QRT-PCR) were used to examine the expression of CETN2 in clinical samples in relation to the effectiveness of chemotherapy. The capacity of CETN2 to predict chemotherapy results was proven by receiver operating characteristic (ROC) curves after the construction of two prediction models, the logistic regression model and the decision tree model. The impact of CETN2 on prognosis was examined using the Kaplan-Meier technique. RESULTS: CETN2 was associated with NER, oxidative phosphorylation (OXPHOS) and cell cycle pathways in ovarian cancer drug-resistant samples. In clinical samples, CETN2 showed its possible correlation with immune infiltration. The protein expression level of CETN2 was significantly higher in platinum-resistant patients than that in platinum-sensitive patients, and the expression level had some predictive value for chemotherapy outcome, and high CETN2 protein expression was associated with poorer progression-free survival. CONCLUSIONS: CETN2 protein had a significant effect on ovarian cancer platinum sensitivity and prognosis, which may be related to the activation of NER, OXPHOS and cell cycle pathways upon CETN2 upregulation. Further research is necessary to determine the therapeutic application value of CETN2, which may be a new biomarker of chemoresponsiveness.


Assuntos
Antineoplásicos , Carcinoma Epitelial do Ovário , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas , Compostos de Platina , Feminino , Humanos , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Reparo do DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Prognóstico , Compostos de Platina/farmacologia , Compostos de Platina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
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