Publications by authors named "Guilherme Souza Silva"

The unprecedented global impact caused by SARS-CoV-2 imposed huge health and economic challenges, highlighting the urgent need for safe and effective vaccines. The receptor-binding domain (RBD) of SARS-CoV-2 is the major target for neutralizing antibodies and for vaccine formulations. Nonetheless, the low immunogenicity of the RBD requires the use of alternative strategies to enhance its immunological properties.

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Currently, the standard non-invasive test for diagnosing Peripheral Arterial Disease is the Ankle-Brachial Index. However, this test becomes unfeasible in a certain population. New evidence proposes the pedal acceleration time, an ultrasound index, as an alternative test.

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Dendritic cells are central to the development of immunity, as they are specialized in initiating antigen-specific immune responses. In this review, we briefly present the existing knowledge on dendritic cell biology and how their division in different dendritic cell subsets may impact the development of immune responses. In addition, we explore the use of chimeric monoclonal antibodies that bind to dendritic cell surface receptors, with an emphasis on the C-type lectin family of endocytic receptors, to deliver antigens directly to these cells.

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Health professionals working to mitigate the COVID-19 pandemic are one of the main risk groups for the disease, being prioritized for vaccination. Considering this, the aim of this study was to analyze the immune response of these professionals immunized with CoronaVac in the first and second doses. Blood samples were collected after the first and second doses of the vaccine (CoronaVac) and used to investigate hematological and biochemical parameters, analysis of immunoglobulin production, cytokines, and gene expression profile, as well as the identification of subsets of immune cells.

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Objectives: This study aimed to investigate the detection of Epstein-Barr virus (EBV) in oral squamous cell carcinoma (OSCC) and to verify the concordance of EBV-DNA frequency in subgingival sites and in the OSCC.

Methods: A cross-sectional study with 30 OSCC patients, aged from 44 to 88 years old, was conducted. Samples were collected in subgingival sites and at the OSCC, then submitted to DNA isolation, qPCR, and genotyping.

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Article Synopsis
  • Lignins, which are phenolic macromolecules with various applications, were isolated from Crataeva tapia leaves and their properties were examined for potential medicinal and cosmetic uses.
  • The study characterized the lignin through various methods, revealing it to be thermally stable with specific elemental compositions and low antioxidant activity.
  • Experimental results showed that the lignin was non-cytotoxic, stimulated certain immune responses, and enhanced UV absorption in commercial creams, highlighting its potential utility in developing sunscreen and other formulations.
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Caesalpinia pulcherrima is a shrub with worldwide distribution used as an ornamental plant. In this study, we extracted a lignin from the C. pulcherrima leaves and investigated its biological functions.

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Left ventricular noncompaction (LVNC) is a congenital pathology that directly affects the lining walls of myocardial tissue, causing trabeculations with blood filling in the inner wall of the heart, concomitantly with the development of a mesocardial thinning. Although LVNC was described for the first time as long ago as 1984, our understanding of the disease with regard to its genetic pattern, diagnosis, clinical presentation and treatment is still scanty. LVNC can present as an isolated condition or associated with congenital heart disease, genetic syndromes or neuromuscular disease.

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Recently, in China, in 2019, a new type of disease has arisen caused by a new strain of coronavirus, the SARS-CoV-2 virus, considered extremely worrying due to its high infectivity power and the easy ability to spread geographically. For patients in general, the clinical features resulting from respiratory syndromes can trigger an asymptomatic condition. However, 25 % of patients infected by SARS-CoV-2 can progress to severity.

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Background: The purpose of this study was to assess the tolerance of early oral feeding after total laryngectomy.

Method: A randomized multicenter study was conducted that included 89 individuals subjected to total laryngectomy. The participants were allocated to 2 groups: early (n = 44), early oral feeding; and late (n = 45), late oral feeding.

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Spontaneous remission is a rare, but well recognized event in oncology. Certain tumours, such as melanomas, hypernephromas and neuroblastomas, are known for showing spontaneous regression. Similarly, spontaneous regression of oral lymphomas, as well as oropharyngeal and recurrent tongue carcinomas, has been reported.

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Objective: To evaluate the incidence of pharyngocutaneous fistula after total laryngectomy and try to identify its predictors.

Methods: From May 2005 to April 2010, 93 patients underwent total laryngectomy. We evaluated complications during and after surgery and compared them with the following variables: gender, nutritional status, previous tracheotomy, tumor location, type of surgery, TNM staging, prior treatment with chemotherapy and/or radiotherapy, use of flaps for reconstruction and surgical margin.

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Unlabelled: Salvage laryngectomy in patients treated with organ preservation protocols is associated with high rates of postoperative complications. The use of non-irradiated tissue flaps in pharyngeal reconstruction could reduce the incidence of these complications.

Objective: This study aims to evaluate the usefulness of the pectoralis major myocutaneous flap in preventing salivary fistulae during the postoperative period of salvage total laryngectomy (TL).

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Objective: To evaluate possible predictive factors of involution on ultrasonography (US) or disappearance of a prenatally detected multicystic dysplastic kidney (MCDK).

Patients And Methods: Forty-five children with unilateral MCDK detected by prenatal ultrasonography between 1989 and 2002 were analysed. All patients except one had (99m)Tc isotopic scintigraphy to confirm the absence of renal function in the MCDK.

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