Publications by authors named "Renata S Mello"

Purpose: To evaluate the safety and performance of Wrapsody™, a cell-impermeable endoprosthesis (CIE), for treating hemodialysis vascular access outflow stenosis.

Materials And Methods: Investigators retrospectively analyzed 113 hemodialysis patients treated with a CIE (11/2021-12/2022) across four centers in Brazil. De novo or restenotic lesions were treated.

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Background: Vascular stenosis commonly leads to dysfunction in hemodialysis vascular access. Although percutaneous transluminal angioplasty is an established treatment, stent utilization has increased in the last decade as an alternative solution to extend the access function. This study evaluated the safety and initial results of a new impermeable covered stent for treating vascular access outflow stenosis.

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Mancozeb is a widely used fungicide whose toxicity has been reported in non-target organisms, being considered to have high or very high acute toxicity to aquatic organisms. However, the toxicity of this compound is not well characterized in the developmental stages of fish. In this study, Danio rerio with 4-, 5-, and 6-days post fertilization (dpf) was exposed to MZ at non-lethal concentrations for 24, 48, or 72 h and subsequently, behavioral alterations, oxidative stress parameters and ERK, p38, and Akt phosphorylation were analyzed.

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Background: The functional autologous arteriovenous fistula is considered the best vascular access for patients on hemodialysis. Some fistulae exhibit maturation problems after creation and do not reach adequate vessel diameter and flow in dialysis. The aim of this study was to describe our technique of oversized balloon angioplasty for assisted maturation of arteriovenous fistulae to accelerate the cannulation and to decrease the time of catheter use and its outcome.

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Article Synopsis
  • Permethrin (PM) is a common insecticide that can harm non-target organisms, particularly during their early development, prompting research on its effects on larval zebrafish.
  • Exposure to PM caused anxiety-like behaviors and increased levels of reactive oxygen species (ROS), linked to cellular damage and oxidative stress.
  • The study found that PM exposure disrupted mitochondrial function and bioenergetic capacity in zebrafish, indicating potential mechanisms behind developmental damage and oxidative stress linked to PM.
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Mancozeb (MZ), a manganese/zinc-containing ethylene-bis-dithiocarbamate (EBCD) fungicide has been claimed to present low acute toxicity and short environmental persistence, however, its effects on embryogenesis in non-target organisms is unclear. Here, we used zebrafish embryos (5 hpf) to assess the potential embryotoxic effects induced by MZ (up to 72 hpf) as well as the role of reactive oxygen species (ROS) in this process by pre-treatment with a classical antioxidant (N-acetylcysteine, NAC). Markers of reactive oxygen species production (ROS), glutathione (GSH) levels and glutathione S-transferase (GST) activity were measured along with genotoxicity (comet assay), cell death (Acridine Orange) and behavioral parameters (spontaneous movement, touch stimulation and swimming response), in order to determine potential mechanisms of embryotoxicity.

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A polyhydroxamicalkanoate (PHA) polymer containing the functional groups hydroxamic acid and carboxylic acid with the ability to accelerate dephosphorylation reactions is proposed. The methodology used to prepare this polymer favored the position of the two functional groups next to each other, which allows for the cooperativity between these groups. This cooperative effect has an important role when one wants to mimic enzymes.

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Mixed micelles of cetyltrimethylammonium bromide (CTABr) or dodecyltrimethylammonium bromide (DTABr) and the alpha-nucleophile, lauryl hydroxamic acid (LHA) accelerate dephosphorylation of bis(2,4-dinitrophenyl)phosphate (BDNPP) over the pH range 4-10. With a 0.1 mole fraction of LHA in DTABr or CTABr, dephosphorylation of BDNPP is approximately 10(4)-fold faster than its spontaneous hydrolysis, and monoanionic LHA(-) is the reactive species.

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Nicotinohydrazide.

Acta Crystallogr Sect E Struct Rep Online

December 2007

The title mol-ecule (alternative name: pyridine-3-carbohydrazide; C(6)H(7)N(3)O) was obtained from the reaction of ethyl nicotinate with hydrazine hydrate in methanol. In the amide group, the C-N bond is relatively short, suggesting some degree of electronic delocalization in the mol-ecule. The stabilized conformation may be compared with those of isomeric compounds picolinohydrazide (pyridine-2-carbohydrazide) and isonicotinohydrazide (pyridine-4-carbohydrazide).

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