Publications by authors named "Marcela Ribeiro"

Glaucoma, a leading cause of irreversible blindness, affects about 70 million people globally. Its treatment focuses on reducing intraocular pressure. Acetazolamide, a potent anti-glaucoma drug, is currently used only systemically due to low solubility and permeation, which cause severe side effects.

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Aim: To investigate the hypothesis supporting the link between periodontitis and dopaminergic neuron degeneration.

Materials And Methods: Adult male Wistar rats were used to induce dopaminergic neuronal injury with 6-hydroxydopamine (6-OHDA) neurotoxin and experimental periodontitis via ligature placement. Motor function assessments were conducted before and after periodontitis induction in controls and 6-OHDA-injury-induced rats.

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Oxidative stress is an undesirable effect of culture, which requires antioxidant supplementation. This study investigated the analogue of resveratrol (RA33) as an alternative to resveratrol, an antioxidant molecule, for the culture of -fertilized bovine embryos. The effect of different concentrations of RA33 on embryo development was evaluated and a comparison between RA33 and resveratrol was performed.

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The present study is a systematic review of the evaluation of screening programs as a strategy for early detection of oral cancer. The aim of this study was to assess whether screening through visual inspection is able to identify injuries in early stages, to increase survival, and to decrease the incidence and mortality of oral cancer. Studies using visual inspection to screen for oral cancer and potentially malignant lesions in apparently healthy individuals over 18 years without previous diagnosis of the disease were included.

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Since the possibility of silencing specific genes linked to retinal degeneration has become a reality with the use of small interfering RNAs (siRNAs), this technology has been widely studied to promote the treatment of several ocular diseases. Despite recent advances, the clinical success of gene silencing in the retina is significantly reduced by inherent anatomical and physiological ocular barriers, and new strategies are required to achieve intraocular therapeutic effectiveness. In this study, we developed lipoplexes, prepared with sodium alginate as an adjuvant and strategically coated with hyaluronic acid (HA-LIP), and investigated the potential neuroprotective effect of these systems in a retinal light damage model.

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Article Synopsis
  • - The study focuses on human Pluripotent Stem Cell (hPSC) technology, specifically using human Embryonic Stem cell derived-Retinal Pigmented Epithelial Cells (hES-RPE) for applications like cell therapy and drug screening, aiming to address eye diseases with a high socioeconomic impact.
  • - Research findings indicate that hES-RPE cells more closely mimic natural Retinal Pigmented Epithelial (RPE) cells compared to the widely used ARPE-19 cell line, showcasing superior resilience when exposed to various immunosuppressive drugs.
  • - The results suggest that hES-RPE cells could perform a wider range of RPE functions than ARPE-19, making them a promising candidate for future drug
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Purpose: To verify the safety of different doses of intravitreal metoprolol tartrate (MT) after intravitreal injection in rabbit eyes.

Methods: Animals were randomly assigned into 2 groups: group I received 50 µg of MT and group II 100 µg of MT. A volume of 0.

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Currently, most nonviral nucleic acid vectors are in the form of colloidal suspensions administered primarily parenterally. This type of formulation and the mode of administration impose strong constraints such as the size of the administered vectors or the production of sterile preparations. The tablet form provides access to easy oral administration, well accepted by patients; As regards nucleic acid vectors, a dry form represents an advance in terms of stability.

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Flower cultivation in greenhouses enhances productivity and ensures high-quality product supply throughout the year. However, under such protected environments, climate conditions are designed to favor flower growth and can intensify occupational exposure to pesticides. In this study, flower greenhouse workers were tested for cholinesterase inhibition, a valuable indicator of occupational exposure to organophosphate and carbamate pesticides.

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Purpose: To assess the in vivo release profile and the retinal toxicity of a poly (lactic-co-glycolic acid) (PLGA) sustained-release sirolimus (SRL) intravitreal implant in normal rabbit eyes.

Methods: PLGA intravitreal implants containing or not SRL were prepared, and the viability of ARPE-19 and hES-RPE human retinal cell lines was examined after 24 and 72 h of exposure to implants. New Zealand rabbits were randomly divided into two groups that received intravitreal implants containing or not SRL.

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Protein glycosylation is one of the most studied post-translational modifications and has received considerable attention for its critical role in the cell biology of eukaryotic cells. The genus Trichoderma has been extensively studied in the biocontrol of soil-borne fungal phytopathogens. The aim of this study was to identify the proteins secreted from Trichoderma harzianum after interacting with the cell walls of two phytopathogens, Sclerotinia sclerotiorum and Fusarium oxysporum.

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We investigated feeding and reproductive performance of coexisting pelagic turbellarians from experiments on predation rates of Mesostoma ehrenbergii and M. craci as a function of food (Daphnia similis, three levels) and temperature (4 levels) during 10 days. Flatworms were collected from the pelagic of a subtropical lake in Brazil.

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A new furostane steroidal saponin was isolated from the leaves of Agave angustifolia var. marginata. On the basis of chemical conversions and spectroscopic analyses, its structure was established as 3-[O-β-d-glucopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→3)-O]-[O-6-deoxy-α-l-mannopyranosyl-(1→4)-β-d-xylopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranosyl)oxy]-(3β,5α,22α,25R)-26-(β-d-glucopyranosyloxy)-22-methoxy-furostane (1).

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Introduction: Sensitization is associated with worse clinical outcomes after kidney transplantation (KT), including increased incidence of delayed graft function, acute rejection (AR) and graft loss.

Objectives: To evaluate 1-year efficacy and safety outcomes in sensitized KT recipients receiving antithymocyte globulin (ATG) induction and compare them to non-sensitized patients.

Methods: Deceased donors KT recipients transplanted between January 1998 and December 2009 were divided into 5 groups: control group 1 -n = 89, PRA negative, without induction therapy; control group 2 - n = 94, PRA negative, basiliximab induction; control group 3 - n = 81, PRA negative, ATG induction; test group 4 - n = 64, PRA 1-49%, ATG induction; test group 5 -n = 118, PRA ≥ 50%, ATG induction.

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Arsenic is an ametal ubiquitous in nature and known by its high toxicity. Many studies have tried to elucidate the arsenic metabolism in the cell and its impact to plants, animals and human health. In aqueous phase, inorganic arsenic is more common and its oxidation state (As III and As V) depends on physical and chemical environmental conditions.

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As part of our search of bioactive saponins from Brazilian plants, phytochemical study of the seeds of Inga laurina led to the isolation of a new complex triterpenoid saponin, named ingasaponin. It is the first saponin isolated from a species of Inga genus. It was isolated by using chromatographic methods and its structural elucidation was performed using detailed analyses of (1)H and (13)C NMR spectra including 2D-NMR spectroscopic techniques and chemical conversions.

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High diesel exhaust particle levels are associated with increased health effects; however, knowledge on the impact of its chemical contaminant 1,2-naphthoquinone (1,2-NQ) is limited. We investigated whether postnatal and adult exposures to 1,2-NQ influence allergic reaction and the roles of innate and adaptive immunity. Male neonate (6 days) and adult (56 days) C57Bl/6 mice were exposed to 1,2-NQ (100 nM; 15 min) for 3 days, and on day 59, they were sensitized and later challenged with ovalbumin (OVA).

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In this paper we address the "skull-stripping" problem in 3D MR images. We propose a new method that employs an efficient and unique histogram analysis. A fundamental component of this analysis is an algorithm for partitioning a histogram based on the position of the maximum deviation from a Gaussian fit.

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In this preliminary study the occupational safety and health practices among flower greenhouses workers were evaluated. The study was carried out in the alto Tietê region, located at the Sao Paulo State, Brazil. Inadequate welfare facilities; poor pesticide storage, use and disposal conditions; use of highly toxic pesticides; lack of adequate data regarding pesticide use; and incorrect use and maintenance of PPE were observed in most of the visited greenhouses.

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A competitive enzyme-linked immunosorbent test using the PR1 recombinant major surface protein 5 (rMSP5-PR1-ELISA) of Anaplasma marginale was standardized and validated using sera from anaplasmosis free and endemic regions. The sequencing of the msp5 gene of PR1 isolate showed 98% of identity with the Florida and Saint Maries isolates, 97% with Brazil (Pernambuco) and Havana isolates; and 91% with A. centrale.

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Propylthiouracil (PTU), a thyonamide class drug commonly used to treat hyperthyroidism has been reported to cause adverse reactions in 3% to 12% of patients. The side effects have been described more frequently as mild, but ocasionally severe fatal reactions may occur. We report the case of a fourteen years old patient in use of PTU for the last three years who presented with fever, hemorrhagic blisters, necrotic ulcers, and that developed purpuric lesions and nodules in lower extremities.

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The use of PCR for molecular diagnosis is accepted as the standard method for detecting nucleic acids from numerous major infectious agents using diverse sampling techniques. Although PCR is an essential tool in the research laboratory; the success of the method depends on a sample free of inhibitors that was obtained preferably by a simple and fast extraction method. The coagglutination test (COA test) is based on the propriety of protein A, from Staphylococcus aureus, which can bind specifically to the Fc portion of immunoglobulin G (IgG) in various mammals and to several IgG subclasses in mice.

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In this work we describe the isolation of a new l-amino acid oxidase (LAAO) referred to as BpirLAAO-I from Bothrops pirajai snake venom, which was highly purified using a combination of molecular exclusion, affinity, and hydrophobic chromatography steps. BpirLAAO-I homodimeric acid glycoprotein (approximate Mr and pI of 130,000 and 4.9, respectively) displays high specificity toward hydrophobic/aromatic amino acids, while deglycosylation does not alter its enzymatic activity.

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In Brazil, problems regarding protection from hazardous substances in small-sized enterprises are similar to those observed in many other countries. Looking for a simple tool to assess and control such exposures, FUNDACENTRO has started in 2005 a pilot-project to implement the International Chemical Control Toolkit. During the series of visits to foundries, it was observed that although many changes have occurred in foundry technology, occupational exposures to silica dust and metal fumes continue to occur, due to a lack of perception of occupational exposure in the work environment.

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Schistosoma mansoni is the primary causative agent of schistosomiasis, which affects 200 million individuals in 74 countries. We generated 163,000 expressed-sequence tags (ESTs) from normalized cDNA libraries from six selected developmental stages of the parasite, resulting in 31,000 assembled sequences and 92% sampling of an estimated 14,000 gene complement. By analyzing automated Gene Ontology assignments, we provide a detailed view of important S.

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