Immunological memory, a fundamental immune system mechanism, is instrumental in long-term protection. Successful vaccines can elicit and sustain immunological memory against pathogens for the long term. Memory B cells (MBC) are key players in secondary responses due to their longevity and rapid differentiation into high-affinity antibody-secreting cells upon second antigen exposure.
View Article and Find Full Text PDFForest Islands and their adjacent natural grasslands are vulnerable and sensitive ecosystems to the actions of severe fires, which result in losses of their resilience, which makes the potential of passive restoration of these environments unfeasible after such events. This study aims to verify, through an autochthonous species exclusive to these Forest Islands, whether it can develop in Histosols around a Forest Island that has been degraded by fire for years. The place of study and collection of the material tested was in the Sempre-Vivas National Park.
View Article and Find Full Text PDFPharmaceuticals (Basel)
April 2024
Objective: This study evaluated the influence of cannabis and/or cocaine use in human immunodeficiency virus (HIV)- and cytomegalovirus (CMV)-specific T-cell responses of people with HIV (PWH).
Results: There was a higher percentage of IL-17-producing HIV-Gag-specific CD8+ T-cells in all drug users than that in PWH non-drug users. Stratifying the drug-user groups, increased percentages of IL-17-producing HIV-Gag-specific CD4+ and CD8+ T-cells were found in PWH cannabis plus cocaine users compared to PWH non-drug users.
The encounter of T cells with the antigen through the interaction of T cell receptors with peptides and major histocompatibility complex (MHC) molecules on the surface of antigen-presenting cells (APCs) can generate effector response and memory T cells. Memory T cells developed following infections or vaccination may persist, leading to the generation of a specific immune response upon reexposure to the same pathogen through rapid clonal proliferation and activation of effector functions. T cell memory subsets can be identified based on the expression of several membrane markers such as CCR7, CD27, and CD45RA.
View Article and Find Full Text PDFBackground: Transcriptomics has been used to evaluate immune responses during malaria in diverse cohorts worldwide. However, the high heterogeneity of cohorts and poor generalization of transcriptional signatures reported in each study limit their potential clinical applications.
Methods: We compiled 28 public data sets containing 1556 whole-blood or peripheral blood mononuclear cell transcriptome samples.
Malaria is a parasitic infection responsible for high morbidity and mortality rates worldwide. During the disease, phagocytosis of infected red blood cells by the macrophages induces the production of reactive oxygen (ROS) and nitrogen species (RNS), culminating in parasite death. Curcumin (CUR) is a bioactive compound that has been demonstrated to reduce the production of pro-inflammatory cytokines and chemokines produced by macrophages but to reduce parasitemia in infected mice.
View Article and Find Full Text PDFIntroduction: Infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces rapid production of IgM, IgA, and IgG antibodies directed to multiple viral antigens that may have impact diverse clinical outcomes.
Methods: We evaluated IgM, IgA, and IgG antibodies directed to the nucleocapsid (NP), IgA and IgG to the Spike protein and to the receptor-binding domain (RBD), and the presence of neutralizing antibodies (nAb), in a cohort of unvaccinated SARS-CoV-2 infected individuals, in the first 30 days of post-symptom onset (PSO) (T1).
Results: This study included 193 coronavirus disease 2019 (COVID-19) participants classified as mild, moderate, severe, critical, and fatal and 27 uninfected controls.
Immune responses after COVID-19 vaccination should be evaluated in different populations around the world. This study compared antibody responses induced by ChAdOx1 nCoV-19, CoronaVac, and BNT162b2 vaccines. Blood samples from vaccinees were collected pre- and post-vaccinations with the second and third doses.
View Article and Find Full Text PDFZika virus (ZIKV) is an emerging virus from the Flaviviridae family and Flavivirus genus that has caused important outbreaks around the world. ZIKV infection is associated with severe neuropathology in newborns and adults. Until now, there is no licensed vaccine available for ZIKV infection.
View Article and Find Full Text PDFMicrobiol Spectr
February 2023
Severe manifestations of coronavirus disease 2019 (COVID-19) and mortality have been associated with physiological alterations that provide insights into the pathogenesis of the disease. Moreover, factors that drive recovery from COVID-19 can be explored to identify correlates of protection. The cellular metabolism represents a potential target to improve survival upon severe disease, but the associations between the metabolism and the inflammatory response during COVID-19 are not well defined.
View Article and Find Full Text PDFHigher endotoxin in the circulation may indicate a compromised state of host immune response against coinfections in severe COVID-19 patients. We evaluated the inflammatory response of monocytes from COVID-19 patients after lipopolysaccharide (LPS) challenge. Whole blood samples of healthy controls, patients with mild COVID-19, and patients with severe COVID-19 were incubated with LPS for 2 h.
View Article and Find Full Text PDFPurinergic signaling modulates immune function and is involved in the immunopathogenesis of several viral infections. This study aimed to investigate alterations in purinergic pathways in coronavirus disease 2019 (COVID-19) patients. Mild and severe COVID-19 patients had lower extracellular adenosine triphosphate and adenosine levels, and higher cytokines than healthy controls.
View Article and Find Full Text PDFFront Genet
June 2022
Zika virus (ZIKV) is an arbovirus mainly transmitted by mosquitos of the genus . The first cases of ZIKV infection in South America occurred in Brazil in 2015. The infection in humans causes diverse symptoms from asymptomatic to a syndrome-like dengue infection with fever, arthralgia, and myalgia.
View Article and Find Full Text PDFDistinct thermal therapies have been used for cancer therapy. For hyperthermia (HT) treatment the tumour tissue is heated to temperatures between 39 and 45°C, while during ablation (AB) temperatures above 50°C are achieved. HT is commonly used in combination with different treatment modalities, such as radiotherapy and chemotherapy, for better clinical outcomes.
View Article and Find Full Text PDFInt Arch Otorhinolaryngol
April 2022
Palatine and pharyngeal tonsils are the first line of defense against pathogens. Clinically, two alterations may require surgical removal of the tonsils: hypertrophy and recurrent tonsillitis. The two conditions probably result from a dysfunction of the immune system.
View Article and Find Full Text PDFBackground: COVID-19 pandemic continues to be a priority in public health worldwide, and factors inherent to SARS-CoV-2 pathogenesis and genomic characteristics are under study. Investigations that evaluate possible risk factors for infection, clinical manifestations, and viral shedding in different specimens also need to clarify possible associations with COVID-19 prognosis and disease outcomes.
Study Design: In this study, we evaluated SARS-CoV-2 positivity and estimated viral loads by real-time RT-PCR in stool, sera, and urine samples from 35 patients, with a positive SARS-CoV-2 RNA molecular test in respiratory sample, attended at a University COVID-19 referral hospital in Goiania, Goias, Brazil.
Zika virus (ZIKV) is an arbovirus from the Flaviviridae family and Flavivirus genus. Neurological events have been associated with ZIKV-infected individuals, such as Guillain-Barré syndrome, an autoimmune acute neuropathy that causes nerve demyelination and can induce paralysis. With the increase of ZIKV infection incidence in 2015, malformation and microcephaly cases in newborns have grown considerably, which suggested congenital transmission.
View Article and Find Full Text PDFCoinfection 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.
View Article and Find Full Text PDFMucosal barrier alterations may play a role in the pathogenesis of several diseases, including COVID-19. In this study we evaluate the association between bacterial translocation markers and systemic inflammation at the earliest time-point after hospitalization and at the last 72 h of hospitalization in survivors and non-survivors COVID-19 patients. Sixty-six SARS-CoV-2 RT-PCR positive patients and nine non-COVID-19 pneumonia controls were admitted in this study.
View Article and Find Full Text PDFWe verified the prevalence of adequacy in prenatal care considering nutritional assistance and associated factors. It is a cross-sectional study, part of Maternar Cohort Study, conducted between 2018-2019 in Southern Brazil. Women were interviewed during hospitalization in the immediate postpartum period and data were collected from the prenatal chart.
View Article and Find Full Text PDFObjectives: This study using contralateral teeth from human cadavers assessed the amount of unprepared wall surface areas (USA), accumulated hard tissue debris (AHTD), and dentinal crack formation after root canal preparation using either reciprocating or rotary instruments.
Materials And Methods: Incisors with a single root canal from 11 human mandibles had their root canals prepared with Reciproc or Mtwo. Each contralateral tooth was treated with one of the test instruments in order to create matched pairs.
Cytokine
May 2021
Illicit drug use can cause a variety of effects including alterations in the immune system. The aim of this study was to investigate the effects of illicit drugs on circulating lipopolysaccharide (LPS), systemic inflammation and oxidative stress markers in drug users. We evaluated the levels of soluble CD14 (sCD14), LPS, inflammatory (TNF-α and IL-6) and regulatory (IL-10) cytokines, as well as C-reactive protein (CRP), lipid peroxidation (TBARS) and total thiols in the peripheral blood of 81 men included in groups of cannabis (n = 21), cocaine (n = 12), cannabis-plus-cocaine users (n = 27), and non-drug users (n = 21).
View Article and Find Full Text PDFMegacolon is one of the main late complications of Chagas disease, affecting approximately 10% of symptomatic patients. However, studies are needed to understand the mechanisms involved in the progression of this condition. During infection by Trypanosoma cruzi (T.
View Article and Find Full Text PDFOperational tolerance (OT) is the phenomenon occurring in human renal and liver transplantation in which the body does not reject the organ after discontinuing immunosuppression for at least a year. We revisited the data generated by The Brazilian Multicenter Study on Operational Tolerance involving different conceptual fields - antigen-specific cytokine response, immune cell numbers and repertoire, signaling pathways, and epigenetics. We integrated our data to pave the way to systems biology thinking and harness debate on potential mechanisms in OT.
View Article and Find Full Text PDFIn this study, we evaluated the effects of autologous serum collected after two types of exercise on the in vitro inflammatory profile and T cell phenotype of resting peripheral blood mononuclear cells (PBMCs) in obese men. Serum samples and PBMCs were obtained from eight obese men who performed two exercise bouts-high intensity interval exercise (HIIE) and exhaustive exercise session to voluntary fatigue-in a randomized cross-over trial. Pre-exercise PBMCs were incubated with 50% autologous serum (collected before and after each exercise bout) for 4 h.
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