Publications by authors named "Casseb J"

Background: Neurological manifestations associated with COVID-19 remain partially described, mainly in low- and middle-income countries where diagnostic tools are limited. To address this, we assembled medical centers in Brazil with the goal of describing neurological syndromes associated with COVID-19 during the first wave of the pandemic.

Methods: From June 1st, 2020 to June 1st, 2021, non-consecutive adult patients with new onset of six neurological syndromes up to 60 days after confirmed COVID-19 were included.

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The human T-cell lymphotropic virus type 1 (HTLV-1) is a single-stranded positive-sense RNA virus that belongs to the Retroviridae family, genus Deltaretro, and infects approximately five to 10 million people worldwide. Although a significant number of individuals living with HTLV-1 remain asymptomatic throughout their lives, some develop one or more severe clinical conditions, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a progressive and debilitating disease, and/or a subtype of non-Hodgkin's lymphoma with a more threatening course known as adult T-cell leukemia/lymphoma (ATLL). Moreover, current therapeutic options are limited and focus primarily on treating symptoms and controlling viral latency.

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The presence of genetic mutations in HIV poses a significant challenge, potentially leading to antiretroviral resistance and hampering therapeutic development. The Brazilian population has presented variations in the HIV envelope V3 loop gene, especially the GWGR motif. This motif has been linked to reduced transmission potential and slower CD4+ T cell decline.

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Human T-Lymphotropic Virus type-1 (HTLV-1) is a unique retrovirus associated with both leukemogenesis and a specific neuroinflammatory condition known as HTLV-1-Associated Myelopathy (HAM). Currently, most proposed HAM biomarkers require invasive CSF sampling, which is not suitable for large cohorts or repeated prospective screening. To identify non-invasive biomarkers for incident HAM in a large Brazilian cohort of PLwHTLV-1 (n=615 with 6,673 person-years of clinical follow-up), we selected all plasma samples available at the time of entry in the cohort (between 1997-2019), in which up to 43 cytokines/chemokines and immune mediators were measured.

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Several studies suggest that HTLV-1 infection may be associated with a wider spectrum of neurological and clinical manifestations that do not meet diagnostic criteria for HAM. These conditions may later progress to HAM or constitute an intermediate clinical form: intermediate syndrome (IS), a mid-point between asymptomatic HTLV-1 carriers and those with full myelopathy. Thus, we determined the incidence of HAM cases in the HTLV-1-asymptomatic and IS patients, and the clinical/laboratory associated markers.

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Despite being subject to lower AIDS-related mortality rates and having a higher life expectancy, patients with HIV are more prone to develop non-AIDS events. A low CD4+/CD8+ ratio during antiretroviral therapy identifies people with heightened immune senescence and increased risk of mortality. In clinical practice, finding determinants of a low CD4+/CD8+ ratio may be useful for identifying patients who require close monitoring due to an increased risk of comorbidities and death.

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Despite care and the availability of effective antiretroviral treatment, some human immunodeficiency virus (HIV)-infected individuals suffer from neurocognitive disorders associated with HIV (HAND) that significantly affect their quality of life. The different types of HAND can be divided into asymptomatic neurocognitive impairment, mild neurocognitive disorder, and the most severe form known as HIV-associated dementia. Little is known about the mechanisms of HAND, but it is thought to be related to infection of astrocytes, microglial cells, and macrophages in the human brain.

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Human T-lymphotropic virus 1 (HTLV-1) infected individuals remain as asymptomatic carriers (ACs) or can develop the chronic neurological disorder HTLV-1-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP) or the adult T-cell leukemia/lymphoma (ATLL), and the immunological mechanisms involved in this pathologies need to be elucidated. Recently, it has been demonstrated that induced or naturally developed IgG repertoires obtained from different groups of donors, grouped by immune status, can modulate human T and B cell functions. Here we aimed to evaluate if the IgG obtained from HTLV-1-infected ACs, HAM/TSP, and ATLL patients can differentially modulate the production of cytokines by human T and B cells.

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Despite the accuracy of confirmatory tests for the diagnosis of human T cell lymphotropic virus (HTLV), inconclusive or false-negative results still occur when diagnosing human T cell lymphotropic virus type 2 (HTLV-2)-positive patients. The goal of this study was to evaluate the sensitivity and accuracy of a confirmatory immunoassay, the Multi-HTLV assay. A total of 246 plasma samples were tested by real-time polymerase chain reaction (qPCR) and used to calculate the sensitivity and typing accuracy of the Multi-HTLV assay.

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Article Synopsis
  • Small RNAs (sRNAs) play a significant role in regulating biological processes linked to leukemia development, especially in adult T-cell leukemia/lymphoma (ATLL) related to HTLV-1.
  • The study focuses on the sRNA profile of a 30-year-old woman diagnosed with ATLL, analyzing changes before and after maintenance therapy.
  • The goal is to understand how the levels of sRNA expression correlate with the patient’s response to the treatment.
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Persistent viruses are hard to be eradicated, even using effective medications, and can persist for a long time in humans, sometimes regardless of treatment. Hepatitis B virus, hepatitis C virus, human immunodeficiency virus, and human T cell lymphotropic virus infections, the most common in our era, are still a challenge despite the increased knowledge about their biology. Most of them are highly pathogenic, some causing acute disease or, more often, leading to chronic persistent infections, and some of the occult, carrying a high risk of morbidity and mortality.

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Article Synopsis
  • HAM/TSP is a serious illness that affects the spinal cord and currently has no good treatments.
  • Scientists are looking for specific indicators, called biomarkers, to help understand and predict the disease better.
  • This study found some important small RNA molecules that may help in identifying HAM/TSP and understanding how it works in the body.
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Background: Mother-to-child transmission (MTCT) of human T-lymphotropic virus type 1 (HTLV-1) is an important route of transmission that can cause lifelong infection. There is high morbidity and mortality due to adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy (HAM), and other inflammatory disorders. These conditions develop in nearly 10% of people with HTLV-1 infection, with a higher risk if infection occurs early in life.

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Background: For people with HIV and CD4 counts >500 cells/mm, early initiation of antiretroviral therapy (ART) reduces serious AIDS and serious non-AIDS (SNA) risk compared with deferral of treatment until CD4 counts are <350 cells/mm. Whether excess risk of AIDS and SNA persists once ART is initiated for those who defer treatment is uncertain.

Methods: The Strategic Timing of AntiRetroviral Treatment (START) trial, as previously reported, randomly assigned 4684 ART-naive HIV-positive adults with CD4 counts .

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Background: Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes severe diseases, such as aggressive cancer or progressive neurological disease. HTLV-1 affects mainly people in areas with low human development index and can be transmitted from mother to child, primarily through breastfeeding. Refraining from breastfeeding is an effective intervention to reduce the risk of infection in infants.

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Understanding the effect of the HIV, HTLV-1, and HCV viruses on cognitive aspects can help in the better characterization of dementia, as well as the best conducts to be suitable for rehabilitation. Thus, the present study aimed to characterize and compare the neuropsychological profile of 3 groups of patients with infectious diseases: HIV, HTLV, and HCV. The results of neuropsychological assessments and depression assessment of 325 people treated at a referral hospital for infectious diseases were analyzed, being 120 HIV carriers (74 (61.

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HIV-1 infection in the absence of treatment results in progression toward AIDS. Host genetic factors play a role in HIV-1 pathogenesis, but complete knowledge is not yet available. Since less-expressed HLA-C variants are associated with poor HIV-1 control and unstable HLA-C variants are associated with higher HIV-1 infectivity, we investigated whether there was a correlation between the different stages of HIV-1 progression and the presence of specific HLA-C allotypes.

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Background: HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) is an incapacitating neuroinflammatory disorder for which no disease-modifying therapy is available, but corticosteroids provide some clinical benefit. Although HAM/TSP pathogenesis is not fully elucidated, older age, female sex and higher proviral load are established risk factors. We investigated systemic cytokines and a novel chronic inflammatory marker, GlycA, as possible biomarkers of immunopathogenesis and therapeutic response in HAM/TSP, and examined their interaction with established risk factors.

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Interferon-gamma (IFN-γ) plays a crucial role in viral infections by preventing viral replication and in the promotion of innate and adaptive immune responses. However, IFN-gamma can exert distinct effects in different persistent viral infections. The long-term overproduction of IFN-γ in retroviral infections, such as the human immunodeficiency virus (HIV), human T-lymphotropic virus type 1 (HTLV-1), and human endogenous retroviruses (HERVs), resulting in inflammation, may cause neuronal damage.

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During millions of years, viruses have emerged and reemerged, with imbalance of photogenicity and transmissivity overtime. This letter describes that sometimes the nomenclature is uncertain what may actually happen during retrovirus evolution nowadays. This article discusses a possibility that human T-lymphotropic virus type 2 (HTLV-2) has been processed to incorporate the human genome in the last millions of years.

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Human T cell lymphotropic virus (HTLV)-1-associated myelopathy is a chronic, disabling inflammatory disorder of the spinal cord caused by HTLV-1 infection. The diagnosis of HTLV-1-associated myelopathy (HAM) is based on clinical and laboratorial findings. The disease is characterized by the presence of spastic paraparesis associated with detection of anti-HTLV-1 antibodies or HTLV-1 genomes in blood and cerebrospinal fluid (CSF).

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Human T cell lymphotropic virus (HTLV) is the caustive agent of two main conditions i. e., the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and the adult T-cell leukemia/lymphoma (ATLL).

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