Publications by authors named "Marciano Paes"

Article Synopsis
  • Dengue virus (DENV) is a major global health issue, particularly affecting tropical regions, and can cause severe illness in some patients, though the reasons behind this severity are not completely understood.
  • This study aimed to analyze liver tissues from three children who died from DENV to identify histopathological features, cytokine profiles, and immune cell populations.
  • Findings revealed significant liver damage, including vascular dysfunction and increased inflammatory cells, suggesting that these factors contribute to severe liver complications in children infected with DENV.
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Dengue virus (DENV) infection represents a worldwide public health concern and can cause damage to multiple organs, including the kidney. In this work, we investigated the histopathological changes caused by dengue virus infection along with the detection of inflammatory mediators, cytokines, and cell expression patterns in the renal tissue of three fatal cases in children. Hematoxylin and Eosin staining was performed to analyze these histopathological changes.

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Although vertical transmission of CHIKV has been reported, little is known about the role of placenta in the transmission of this virus and the effects of infection on the maternal-fetal interface. In this work we investigated five placentas from pregnant women who became infected during the gestational period. Four formalin-fixed paraffin-embedded samples of placenta (cases 1-4) were positive for CHIKV by RT-PCR.

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SARS-CoV-2 is a virus that belongs to the genus of the family. Other coronaviruses, such as SARS-CoV and MERS-CoV, were associated with complications in pregnant women. Therefore, this study aimed to report the clinical history of five pregnant women infected with SARS-CoV-2 (four symptomatic and one asymptomatic who gave birth to a stillborn child) during the COVID-19 pandemic.

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Chikungunya virus (CHIKV) is an arthropod-borne virus first isolated in Tanzania, Africa. The virus has spread to Asia as well as South and Central America through infected mosquitoes. Vertical transmission may also occur, and was first documented during a chikungunya outbreak in La Réunion Island in 2005.

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Dengue viral (DENV) infections can lead to acute pancreatitis and associated tissue damage. This study examined the pancreas from two fatal cases of DENV for histopathological changes as well as for the detection of cytokines, and other inflammatory mediators. Tissue sections were prepared for examination by ultrastructural and histopathological techniques.

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Article Synopsis
  • Chikungunya virus (CHIKV) causes severe joint pain and currently has no specific treatment or vaccine, prompting the need for reliable serological markers for better patient management.
  • The study investigated serum levels of the protein HMGB1 in CHIKV-infected patients, finding significantly higher levels compared to healthy controls, which remained elevated during the acute phase of the illness.
  • Results suggest that HMGB1 could serve as a useful biomarker for diagnosing and managing chikungunya fever, linking its levels to the severity of the infection.
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The analysis of dengue virus (DENV) infected tissues in mice experimental model and in human biopsies/autopsies may support the pathogenesis studies. Through such models, it is possible to investigate possible histopathological changes caused by the infection and detections of different targets of interest, such as viral antigens, immune cells, and cytokines. In this chapter, we showed a brief review of how histological and immunohistochemistry approaches may improve the knowledge in this field.

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Intrauterine transmission of the Chikungunya virus (CHIKV) during early pregnancy has rarely been reported, although vertical transmission has been observed in newborns. Here, we report four cases of spontaneous abortion in women who became infected with CHIKV between the 11th and 17th weeks of pregnancy. Laboratorial confirmation of the infection was conducted by RT-PCR on a urine sample for one case, and the other three were by detection of IgM anti-CHIKV antibodies.

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In Brazil, an epidemic of Zika virus (ZIKV) infections was declared in 2015 that coincided with alarming reports of microcephaly in newborns associated with mother infection. Although the virus has placental tropism, changes in the tissue morphology and immunity of infected patients have not yet been elucidated. Here, we investigated the histopathological and ultrastructural changes along with the immunological profile and the BDNF expression in rare placental material.

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Dengue is an arboviral disease caused by dengue virus (DENV), which is transmitted to humans by mosquitoes. Infection by DENV most commonly results in a mild flu-like illness; however, the disease has been increasingly associated with neurological symptomatology. This association draws attention to further investigations on the impact of DENV infection in the host's central nervous system.

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Zika virus (ZIKV) is an emergent arthropod-borne virus whose outbreak in Brazil has brought major public health problems. Infected individuals have different symptoms, including rash and pruritus, which can be relieved by the administration of antiallergics. In the case of pregnant women, ZIKV can cross the placenta and infect the fetus leading to congenital defects.

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Article Synopsis
  • - Dengue virus (DENV) can cause mild symptoms or lead to severe disease, including organ failure, with renal involvement linked to higher mortality rates.
  • - Post-mortem studies of four patients who died from DENV-4 in Brazil revealed significant renal damage, characterized by inflammation, tissue injury, and viral replication indicated by NS3 protein presence.
  • - The observed kidney damage likely resulted from a combination of high viral loads and an intense immune response, leading to increased secretion of inflammatory substances in the kidneys.
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Dengue virus (DENV) is an emerging virus involved in outbreaks in Brazil. The association between the virus and vertical transmission, with disorders in the placenta, has raised a worldwide concern. On the 29th gestational week, a pregnant woman presented severe complications due to a DENV infection leading to maternal and fetus death.

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Dengue is an important mosquito-borne disease and a global public health problem. The disease is caused by dengue virus (DENV), which is a member of the Flaviviridae family and contains a positive single-stranded RNA genome that encodes a single precursor polyprotein that is further cleaved into structural and non-structural proteins. Among these proteins, the non-structural 3 (NS3) protein is very important because it forms a non-covalent complex with the NS2B cofactor, thereby forming the functional viral protease.

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Article Synopsis
  • - A case study from Rio de Janeiro reports Zika virus (ZIKV) detection in the brain of a multiple sclerosis (MS) patient who experienced a severe ADEM-like event.
  • - Testing showed the presence of ZIKV antibodies in the patient's serum and urine, along with ZIKV proteins and immune cell infiltration in a brain biopsy.
  • - The findings suggest that a new immune response triggered by ZIKV might be linked to the ADEM-like syndrome, highlighting the need for accurate diagnosis in MS patients in areas where ZIKV is common.
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Dengue is a mild flu-like arboviral illness caused by dengue virus (DENV) that occurs in tropical and subtropical countries. An increasing number of reports have been indicating that dengue is also associated to neurological manifestations, however, little is known regarding the neuropathogenesis of the disease. Here, using BALB/c mice intravenously infected with DENV-2 strain 66985, we demonstrated that the virus is capable of invading and damaging the host's central nervous system (CNS).

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Zika virus (ZIKV) is an emerging virus involved in recent outbreaks in Brazil. The association between the virus and Guillain-Barré syndrome (GBS) or congenital disorders has raised a worldwide concern. In this work, we investigated a rare Zika case, which was associated with GBS and spontaneous retained abortion.

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In the large Zika virus (ZIKV) epidemic that occurred in Brazil in 2015, the intrauterine fetal exposure to ZIKV was associated with a significant risk of developing microcephaly and neurological disorders in the infected infants. ZIKV-associated disease has since been reported in 24 countries in the Americas. At present, definitive evidence is lacking regarding the intrauterine co-exposure to ZIKV and other viral infections and whether the coinfection impacts the risk of acquiring either infection or disease severity.

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Dengue is an important infectious disease that presents high incidence and yields a relevant number of fatal cases (about 20,000) every year worldwide. Despite its epidemiological relevance, there are many knowledge gaps concerning dengue pathogenesis, especially with regards to the circumstances that drive a mild clinical course to a severe disease. In this work, we investigated the participation of high mobility group box 1 (HMGB1), an important modulator of inflammation, in dengue fatal cases.

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The present report describes a case of splenic rupture due to dengue, a rare complication of dengue that should be considered in any patient with suspected dengue disease who started with left upper quadrant abdominal pain and hypotension. The pathophysiology of this entity is not yet well elucidated, but one of the theories present in the literature is that it is due to a depletion of coagulation factors and platelets leading to intra-splenic hemorrhage and rupture. The RT-PCR technique detected serotype 1 and histopathological studies of the spleen revealed significant atrophy of lymphoid follicles and extensive hemorrhage areas.

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Leishmaniasis remains a serious public health problem in developing countries without effective control, whether by vaccination or chemotherapy. Part of the failure of leishmaniasis control is due to the lack of new less toxic and more effective drugs able to eliminate both the lesions and the parasite. Oxiranes derived from naphthoquinones now being assayed are promising drugs for the treatment of this group of diseases.

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Dengue disease is an acute viral illness caused by dengue virus (DENV) that can progress to hemorrhagic stages leading to about 20000 deaths every year worldwide. Despite many clinical investigations regarding dengue, the immunopathogenic process by which infected patients evolve to the severe forms is not fully understood. Apart from differences in virulence and the antibody cross reactivity that can potentially augment virus replication, imbalanced cellular immunity is also seen as a major concern in the establishment of severe dengue.

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Article Synopsis
  • Dengue fever poses a significant public health threat in Brazil, leading to serious outbreaks and health complications.
  • This study examines maternal and fetal deaths linked to dengue, analyzing tissues from the placenta and umbilical cord using advanced molecular techniques.
  • The presence of dengue virus markers in these tissues suggests that they could serve as valuable tools in investigating fatal cases of dengue, particularly those affecting mothers and their unborn children.
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