Publications by authors named "Reboucas J"

The current chemotherapy for cutaneous leishmaniasis (CL) is accompanied by side effects and drug resistance emergence, encouraging the proposal of new treatment approaches for this disease. ZnTnHex-2-PyP (ZnP hexyl) is a water-soluble Zn(II) porphyrin that exhibits remarkable potential for photodynamic therapy (PDT). This study aimed to investigate the ZnP hexyl-PDT against CL in vivo.

View Article and Find Full Text PDF

In this work, zinc oxide with different morphologies and textural properties were prepared and sensitized with metalloporphyrins (MPs) aiming to improve its solar energy harvesting capability for H production by water splitting under sunlight (a 300 W Xe/Hg lamp). An anionic iron(III)porphyrin and a cationic manganese(III)porphyrin were immobilized on different ZnO solids predominantly by electrostatic interactions. In general, the prepared MP-free ZnO solid yielded modest catalytic results which had apparently no direct correlation with their textural properties or morphology.

View Article and Find Full Text PDF

A heterogenized Mn(III) porphyrin-based catalyst was prepared for dye degradation. The new Mn(III) complex of 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin was immobilized, via covalent bond, in chloropropyl silica gel, generating the material (Sil-Cl@MnP) with a loading of 23 μmol manganese porphyrin (MnP) per gram of Sil-Cl. This material was used as a catalyst in degradation reactions of model dyes, a cationic dye [methylene blue (MB)] and an anionic dye (reactive red 120, RR120), using PhI(OAc) and HO as oxidants.

View Article and Find Full Text PDF

Oxidative stress (OS) and endoplasmic reticulum stress (ERS) are at the genesis of placental disorders observed in preeclampsia, intrauterine growth restriction, and maternal hypothyroidism. In this regard, cationic manganese porphyrins (MnPs) comprise potent redox-active therapeutics of high antioxidant and anti-inflammatory potential, which have not been evaluated in metabolic gestational diseases yet. This study evaluated the therapeutic potential of two MnPs, [MnTE-2-PyP] (MnP I) and [MnT(5-Br-3-E-Py)P]5+ (MnP II), in the fetal-placental dysfunction of hypothyroid rats.

View Article and Find Full Text PDF

and are recognized for their development of resistance and biofilm formation. New therapeutic alternatives are necessary in this context. Etomidate shows potential application in catheters against mixed biofilms of fluconazole-resistant and methicillin-resistant (MRSA).

View Article and Find Full Text PDF

Shrimp is among the most sensitizing food allergens and has been associated with many anaphylaxis reactions. However, there is still a shortage of studies that enable a systematic understanding of this disease and the investigation of new therapeutic approaches. This study aimed to develop a new experimental model of shrimp allergy that could enable the evaluation of new prophylactic treatments.

View Article and Find Full Text PDF

Background: Photodynamic inactivation (PDI) is an attractive alternative to treat infections, especially considering the spread of resistant strains. The combination of the photophysical advantages of Zn(II) porphyrins (ZnPs) and the plasmonic effect of silver nanoparticles (AgNPs) has the potential to further improve PDI. Here, we propose the novel association of polyvinylpyrrolidone (PVP) coated AgNPs with the cationic ZnPs Zn(II) -tetrakis(-ethylpyridinium-2-yl)porphyrin or Zn(II) -tetrakis(-n-hexylpyridinium-2-yl)porphyrin to photoinactivate .

View Article and Find Full Text PDF

is the main cause of superficial candidiasis. While the antifungals available are defied by biofilm formation and resistance emergence, antimicrobial photodynamic inactivation (aPDI) arises as an alternative antifungal therapy. The tetracationic metalloporphyrin Zn(II) -tetrakis(-n-hexylpyridinium-2-yl)porphyrin (ZnTnHex-2-PyP) has high photoefficiency and improved cellular interactions.

View Article and Find Full Text PDF

The global production of aquatic organisms has grown steadily in recent decades. This increase in production results in high volumes of by-products and waste, generally considered to be of low commercial value and part of them are consequently discarded in landfills or in the sea, causing serious environmental problems when not used. Currently, a large part of the reused aquaculture waste is destined for the feed industry.

View Article and Find Full Text PDF

Mn(III) -tetrakis(-ethylpyridinium-2-yl)porphyrin chloride (MnTE-2-PyPCl, BMX-010, and AEOL10113) is among the most studied superoxide dismutase (SOD) mimics and redox-active therapeutics, being currently tested as a drug candidate in a phase II clinical trial on atopic dermatitis and itch. The thermal stability of active pharmaceutical ingredients (API) is useful for estimating the expiration date and shelf life of pharmaceutical products under various storage and handling conditions. The thermal decomposition and kinetic parameters of MnTE-2-PyPCl were determined by thermogravimetry (TG) under nonisothermal and isothermal conditions.

View Article and Find Full Text PDF

Cutaneous leishmaniasis caused by induces a pronounced Th1 inflammatory response characterized by IFN-γ production. Even in the absence of parasites, lesions result from a severe inflammatory response in which inflammatory cytokines play an important role. Different approaches have been used to evaluate the therapeutic potential of orally administrated heat shock proteins (Hsp).

View Article and Find Full Text PDF
Article Synopsis
  • - Photodynamic inactivation (PDI) using ZnTnHex-2-PyP, a potent photosensitizer, shows promise as a safer alternative for treating cutaneous leishmaniasis (CL), especially given the adverse effects and drug resistance seen with current chemotherapy options.
  • - The study demonstrated that ZnTnHex-2-PyP can inactivate over 95% of Leishmania promastigotes at low concentrations and significantly reduce parasite levels in infected macrophages, with minimal toxicity observed to mammalian cells.
  • - Findings suggest that ZnTnHex-2-PyP is stable and more effective than similar compounds, making it a strong candidate for future in vivo studies and potential applications against CL
View Article and Find Full Text PDF

Two classes of heterogenized biomimetic catalysts were prepared and characterized for hydrocarbon oxidations: (1) by covalent anchorage of the three Mn(iii) meso-tetrakis(2-, 3-, or 4-pyridyl)porphyrin isomers by in situ alkylation with chloropropyl-functionalized silica gel (Sil-Cl) to yield Sil-Cl/MnPY (Y = 1, 2, 3) materials, and (2) by electrostatic immobilization of the three Mn(iii) meso-tetrakis(N-methylpyridinium-2, 3, or 4-yl)porphyrin isomers (MnPY, Y = 4, 5, 6) on non-modified silica gel (SiO2) to yield SiO2/MnPY (Y = 4, 5, 6) materials. Silica gel used was of column chromatography grade and Mn porphyrin loadings were deliberately kept at a low level (0.3% w/w).

View Article and Find Full Text PDF

17-N-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin) is an inhibitor of heat shock protein 90 (Hsp90), which has been studied in the treatment of cancer such as leukemia or solid tumors. Alternatively, 17-AAG may represent a promising therapeutic agent against leishmaniasis. However, the delivery of 17-AAG is difficult due to its poor aqueous solubility.

View Article and Find Full Text PDF

Mn(III) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin, (HO)MnTnHex-2-PyP (MnHex) carrying long hexyl chains, is a lipophilic mimic of superoxide dismutase (SOD) and a redox-active drug candidate. MnHex crosses the blood-brain barrier, and improved neurologic outcome and decreased infarct size and inflammation in a rat middle cerebral artery occlusion (MCAO) ischemic stroke model. Yet, the dose and the therapeutic efficacy of Mn porphyrin were limited by an adverse effect of arterial hypotension.

View Article and Find Full Text PDF

Behçet's disease (BD) is a chronic, multisystemic, inflammatory disease characterised by recurrent mucocutaneous, ocular, musculoskeletal, central nervous system, gastrointestinal and vascular manifestations, which may affect blood vessels of any size (1). Venous involvement is more common, but arterial involvement accounts for the major cause of mortality (2, 3). Choosing the adequate technique and timing for correcting aneurysms in BD is still challenging.

View Article and Find Full Text PDF

Background: Cardiomyopathies remain among the leading causes of death worldwide, despite all efforts and important advances in the development of cardiovascular therapeutics, demonstrating the need for new solutions. Herein, we describe the effects of the redox-active therapeutic Mn(III) -tetrakis(-ethylpyridinium-2-yl)porphyrin, AEOL10113, BMX-010 (MnTE-2-PyP), on rat heart as an entry to new strategies to circumvent cardiomyopathies.

Methods: Wistar rats weighing 250-300 g were used in both and experiments, to analyze intracellular Ca dynamics, L-type Ca currents, Ca spark frequency, intracellular reactive oxygen species (ROS) levels, and cardiomyocyte and cardiac contractility, in control and MnTE-2-PyP-treated cells, hearts, or animals.

View Article and Find Full Text PDF

Bacterial levan is a fructose homopolymer that offers great potential in biotechnological applications due to biocompatibility, biodegradability and non-toxicity. This biopolymer possesses diverse multifunctional features, which translates into a wide range of applicability, including in industry, consumer products, pharmaceuticals and biomedicine. Extensive research has identified great potential for its exploitation in human health.

View Article and Find Full Text PDF

The current long-term treatment for leishmaniasis causes severe side effects and resistance in some cases. An evaluation of the anti-leishmanial potential of an HSP90-inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), demonstrated its potent effect against spp. and .

View Article and Find Full Text PDF

Near infrared emission spectroscopy (NIRES) has been investigated to yield a new analytical method for determination of CaO, SiO, AlO, FeO, MgO, and SO in Portland cement samples. The analyses were accomplished by correlation of the second derivative NIRES spectra with reference elemental analyses made by X-ray Fluorescence (XRF), using Partial Least Square (PLS) regression models. Four different types of cements (type II, III, IV and V) were included in the models.

View Article and Find Full Text PDF

Leishmaniasis is a neglected disease present in more than 88 countries. The currently adopted chemotherapy faces challenges related to side effects and the development of resistance. Photodynamic therapy (PDT) is emerging as a therapeutic modality for cutaneous leishmaniasis.

View Article and Find Full Text PDF

Cashew nut allergy is the second most commonly reported tree nut allergy. Traditional allergen immunotherapy presents several clinical drawbacks that can be reduced by using nanoparticles-basedallergen-delivery systems, modulating the immune response towards a protective one. In this context, the goal of this work was to assess the potential of poly(anhydride) nanoparticles (NP) for cashew nut oral immunization.

View Article and Find Full Text PDF

Aims: We aim here to demonstrate that radiation (RT) enhances tumor sensitization by only those Mn complexes that are redox active and cycle with ascorbate (Asc), thereby producing HO and utilizing it subsequently in protein S-glutathionylation in a glutathione peroxidase (GPx)-like manner. In turn, such compounds affect cellular redox environment, described by glutathione disulfide (GSSG)/glutathione (GSH) ratio, and tumor growth. To achieve our goal, we tested several Mn complexes of different chemical and physical properties in cellular and animal flank models of 4T1 breast cancer cell.

View Article and Find Full Text PDF

The quantification of zinc in over-the-counter drugs as commercial propolis extracts by molecular fluorescence technique using meso-tetrakis(4-carboxyphenyl)porphyrin (H TCPP ) was developed for the first time. The calibration curve is linear from 6.60 to 100 nmol L of Zn .

View Article and Find Full Text PDF

We disclose here the studies that preceded and guided the preparation of the metal-based, redox-active therapeutic Mn(III) meso-tetrakis(N-n-butoxyethylpyridyl)porphyrin, MnTnBuOE-2-PyP (BMX-001), which is currently in Phase I/II Clinical Trials at Duke University (USA) as a radioprotector of normal tissues in cancer patients. N-substituted pyridylporphyrins are ligands for Mn(III) complexes that are among the most potent superoxide dismutase mimics thus far synthesized. To advance their design, thereby improving their physical and chemical properties and bioavailability/toxicity profiles, we undertook a systematic study on placing oxygen atoms into N-alkylpyridyl chains via alkoxyalkylation reaction.

View Article and Find Full Text PDF