Publications by authors named "Rodrigo Saar Gomes"

During the infectious process, pathogenic microorganisms must obtain nutrients from the host in order to survive and proliferate. These nutritional sources include the metallic nutrient copper. Despite its essentiality, copper in large amounts is toxic.

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An infectious disease caused by SARS-CoV-2, COVID-19 greatly affects the pediatric population and is 3 times more prevalent in newborns than in the general population. In newborns, the overexpression of immunological molecules may also induce a so-called cytokine storm. In our study, we evaluated the expression of cytokines in newborns admitted to a neonatal ICU whose mothers had SARS-CoV-2 and symptoms of SARS.

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Nowadays, aesthetic concerns have gained attention, especially by patients looking for a less invasive alternative to minor facial corrections. Polymethylmethacrylate (PMMA) is widely used as a soft tissue filler; the demand for this polymer has increased, and along with it, there are some reports of adverse reactions. Such adverse reactions stem from consequences of immune and inflammatory reactions to PMMA.

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Article Synopsis
  • Leishmaniases, particularly tegumentary leishmaniasis (TL), are neglected tropical diseases caused by various Leishmania species and transmitted by sand flies, exhibiting different clinical forms based on genetic and environmental factors.
  • Host genetic factors, like single nucleotide polymorphisms (SNPs) in immune response genes, play a crucial role in either increasing susceptibility or providing resistance to TL, with studies conducted globally, including in Brazil.
  • Understanding these genetic influences can inform future immunotherapy developments since current treatments are often toxic and there is no available vaccine for humans.
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Interleukin-32 (IL-32) is produced during infection, but the components of the parasite that induce its production are unknown. An important multivirulence factor of spp. protozoa is the lipophosphoglycan (LPG), which plays a crucial role in the host-parasite interaction.

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Neutrophils are important cells in protection against microbial infections including visceral leishmaniasis (VL). It is well known that IL-32γ increases the protective T helper 17 cell mediated immune response against Leishmania infantum. Thus, in this study we evaluated whether IL-32 γ can increase the protective role of neutrophils against VL.

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Coinfection with the human immunodeficiency virus (HIV) and Leishmania impairs immune responses, increases treatment failure and relapse rates in patients with American tegumentary leishmaniasis (ATL), as well as visceral leishmaniasis (VL). There is insufficient data on the treatment, relapse, and secondary prophylaxis in patients coinfected with HIV/Leishmania in Brazil. This study investigated patients with HIV/ATL and HIV/VL to describe the outcome of leishmaniasis in patients assisted at a referral hospital of Brazilian midwestern region.

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Background: Cells of the innate immune system undergo long-term functional reprogramming in response to Bacillus Calmette-Guérin (BCG) exposure via a process called trained immunity, conferring nonspecific protection to unrelated infections. Here, we investigate whether BCG-induced trained immunity is able to protect against infections caused by different Leishmania spp., protozoa that cause cutaneous and mucosal or visceral lesions.

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Peripheral inflammation, particularly mediated by monocytes, can cause neuroinflammation in Parkinson's disease (PD). We investigated the mechanism of TLR2-induced cytokine impairment in peripheral monocytes from PD patients and the association between the presence of CD14 TLR10 monocytes and PD severity. Peripheral blood mononuclear cells from PD patients and healthy individuals were evaluated for TLR expression on monocyte subsets (CD14 and CD16 expression) using flow cytometry.

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Electron paramagnetic resonance (EPR) spectroscopy of spin labels was used to study the interactions of amphotericin B (AmB) with the plasma membrane of Leishmania (L.) amazonensis promastigotes, human erythrocytes and J774.A1 murine macrophages, in comparison with reported and novel data for miltefosine (MIL).

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A novel chalcone derivative, LQFM064, demonstrated antileishmanial activity against Leishmania (L.) amazonensis, with an IC value of ~10 μM for the promastigote form. Electron paramagnetic resonance (EPR) spectroscopy of a spin-labeled stearic acid incorporated in the plasma membrane of L.

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How human macrophages can control the intracellular infection with Leishmania is not completely understood. IL-15 and IL-32 are cytokines produced by monocytes/macrophages that can induce antimicrobial mechanisms. Here, we evaluated the effects of recombinant human IL-15 (rhIL-15) on primary human macrophage infection and response to L.

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Using the electron paramagnetic resonance (EPR) of spin-labeled stearic acid and a spin label chemically attached to the membrane proteins, the interaction of miltefosine (MIL) and the ionic surfactants sodium dodecyl sulfate (SDS, anionic), cetyltrimethylammonium chloride (CTAC, cationic) and N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS, zwitterionic) with the plasma membrane of Leishmania (L.) amazonensis promastigotes was studied. The spin-label EPR data indicated that the four compounds studied have the ability to increase the molecular dynamics of membrane proteins to a large extent.

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Objective: Multiple sclerosis (MS) is a multifactorial chronic disease that affects the central nervous system (CNS). Toll-like receptors (TLRs) play a central role in cytokine production after pathogen- and danger-associated molecular patterns (PAMPs and DAMPs) and contribute to CNS damage in MS patients. Here, we evaluated the effects of interferon (IFN)-β treatment in TLR2 and TLR4-dependent cytokine production and mRNA expression in whole-blood cell cultures from MS patients.

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The sesquiterpene nerolidol is a membrane-active compound that has demonstrated antitumor, antibacterial, antifungal and antiparasitic activities. In this study, we used electron paramagnetic resonance (EPR) spectroscopy and biophysical parameters determined via cell culture assays to study the mechanisms underlying the in vitro antileishmanial activity of nerolidol. The EPR spectra of a spin-labeled stearic acid indicated notable interactions of nerolidol with the cell membrane of Leishmania amazonensis amastigotes.

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Phenotypic and functional aspects of monocytes from Localized Cutaneous Leishmaniasis (LCL) patients were evaluated. The frequencies of monocyte subsets and TLR2/TLR4 expression were evaluated in fresh peripheral blood whereas cytokine production was evaluated in whole blood cell cultures stimulated with TLR agonists or Leishmania braziliensis antigen (Ag). CD16 monocytes frequency was increased in patients compared with controls.

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Human leishmaniasis caused by Leishmania (Viannia) braziliensis can be presented as localized cutaneous leishmaniasis (LCL) or mucosal leishmaniasis (ML). Macrophages kill parasites using nitric oxide (NO) and reactive oxygen species (ROS). The aim of this study was to evaluate the ability of parasites obtained from patients with LCL or ML to produce and resist NO or ROS.

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Leishmania (Viannia) guyanensis is a causal agent of American tegumentary leishmaniasis (ATL). This protozoan has been poorly investigated; however, it can cause different clinical forms of ATL, ranging from a single cutaneous lesion to severe lesions that can lead to destruction of the nasopharyngeal mucosa. L.

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Article Synopsis
  • Visceral leishmaniasis (VL) is a chronic parasitic disease prevalent in the Americas, involving an inflammatory response from various immune cells but the role of interleukin-32 (IL-32) has been largely unexplored.
  • Research showed that specific antigens boost levels of IL-32γ mRNA in human immune cells and that transgenic mice expressing IL-32γ had lower parasite levels in their spleens and livers compared to regular mice.
  • The protective effect of IL-32γ was linked to enhanced production of immune factors like nitric oxide and increased Th1 and Th17 T cell responses, suggesting that IL-32γ strengthens the immune response against VL.
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American Tegumentary Leishmaniasis is a chronic infection caused by Leishmania protozoan. It is not known whether genetic variances in NOD-like receptor (NLR) family members influence the immune response towards Leishmania parasites and modulate intracellular killing. Using functional genomics, we investigated whether genetic variants in NOD1 or NOD2 influence the production of cytokines by human PBMCs exposed to Leishmania.

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Platelet-activating factor (PAF) is produced by macrophages during inflammation and infections. We evaluated whether PAF is able to modulate the infection of human macrophages by Leishmania braziliensis, the main Leishmania sp. in Brazil.

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Background: Interleukin 32 (IL-32) is a pro-inflammatory cytokine induced in patients with American tegumentary leishmaniasis (ATL) caused by Leishmania braziliensis. Here, we investigated whether IL-32 is also expressed in patient lesions caused by L. amazonensis.

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Background: Interleukin-32 (IL-32) is expressed in lesions of patients with American Tegumentary Leishmaniasis (ATL), but its precise role in the disease remains unknown.

Methodology/principal Findings: In the present study, silencing and overexpression of IL-32 was performed in THP-1-derived macrophages infected with Leishmania (Viannia) braziliensis or L. (Leishmania) amazonensis to investigate the role of IL-32 in infection.

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Interleukin 32 (IL-32) is a proinflammatory cytokine, expressed as 9 distinct isoforms. The most active isoform is the predominantly intracellular-functioning IL-32γ. Involvement of IL-32 in infectious diseases is increasingly being appreciated.

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While the role of Toll-like receptors (TLRs) has been investigated in murine models of tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis, the interaction between TLRs and Leishmania sp. has not been investigated in human cells. The aim of this study was to evaluate the involvement of TLR4 in cytokine production of human peripheral blood mononuclear cells (PBMCs) induced by L.

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