Publications by authors named "Mayor A"

Persons living with AIDS are highly vulnerable to foodborne enteric infections including recurrent septicemia and toxoplasmosis of the brain with the potential for substantial morbidity and mortality. Patients with immunologic AIDS in Chicago, New Orleans, and Bayamon were interviewed to determine gaps in food safety knowledge and prevalence of related behaviors in order to create targeted educational material for this population. A food safety score was calculated based on responses to 40 knowledge, belief, and behavior questions.

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This is a report of the first Plasmodium vivax congenital malaria case in Guatemala and the first case in Latin America with genotypical, histological and clinical characterization. The findings show that maternal P. vivax infection still occurs in areas that are in the pathway towards malaria elimination, and can be associated with detrimental health effects for the neonate.

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Unlabelled: One of the early events in the development of liver cancer is a neutralization of tumor suppressor proteins Rb, p53, hepatocyte nuclear factor 4α (HNF4α), and CCAAT/enhancer binding protein (C/EBP) α. The elimination of these proteins is mediated by a small subunit of proteasome, gankyrin, which is activated by cancer. The aim of this study was to determine the mechanisms that repress gankyrin in quiescent livers and mechanisms of activation of gankyrin in liver cancer.

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Sequestration of Plasmodium falciparum-infected erythrocytes (PfIE) in the capillaries of the central nervous system (CNS) is the pathognomonic feature of cerebral malaria, a condition frequently leading to death. Sequestration of PfIE in the placental intervillous spaces is the characteristic feature of malaria in pregnancy and is associated with low birthweight and prematurity. Although both patterns of sequestration are thought to result from the expression of different parasite proteins involved in cytoadhesion to human receptors, scant information exists on whether both conditions can coexist and whether this can lead to death.

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Background: Evidence of the presence of Plasmodium vivax in the placenta is scarce and inconclusive. This information is relevant to understanding whether P. vivax affects placental function and how it may contribute to poor pregnancy outcomes.

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Monitoring interventions to prevent malaria in pregnancy requires sensitive detection of placental infection. Rapid diagnostic tests (RDTs) are good candidates, but little information is available on their sensitivity on placental blood. We have evaluated the agreement (kappa coefficient) between microscopy and a Plasmodium falciparum histidine-rich protein 2 (HRP2)-based immuno-chromatographic test (ICT) on placental blood from 1151 women at delivery.

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Background: Estimation of Plasmodium falciparum parasitaemia can vary with the method used and time of sampling. Quantitative real time PCR (qPCR) on whole blood or plasma samples has previously been shown to be more sensitive than thick film microscopy. However the efficiencies of each method have not been compared using samples obtained from infants less than one year old.

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Background: The factors involved in the progression from Plasmodium falciparum infection to severe malaria (SM) are still incompletely understood. Altered antibody and cellular immunity against P. falciparum might contribute to increase the risk of developing SM.

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The role of interleukin-10 (IL-10) in malaria remains poorly characterized. The aims of this study were to investigate (i) whether genetic variants of the IL-10 gene influence IL-10 production and (ii) whether IL-10 production as well as the genotypes and haplotypes of the IL-10 gene in young children and their mothers are associated with the incidence of clinical malaria in young children. We genotyped three IL-10 single nucleotide polymorphisms in 240 children and their mothers from a longitudinal prospective cohort and assessed the IL-10 production by maternal peripheral blood mononuclear cells (PBMCs) and cord blood mononuclear cells (CBMCs).

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Background: The risk of Plasmodium falciparum malaria increases during pregnancy and at early postpartum. Immunological and physiological alterations associated with pregnancy that persist after delivery may contribute to the susceptibility to P. falciparum during early postpartum period.

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The purpose of was to evaluate the renal pathology findings as described by the World Health Organization classification for systemic lupus erythematosus (SLE) in a group of Puerto Rico patients with lupus nephritis and determine the association with clinical and laboratory findings. The medical records from patients seen at the Lu pus Clinic from 1985 to 2005 were reviewed and patients with a performed renal biopsy included. All patients fulfilled the American ColIege of Rheumatology criteria for SLE.

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Background: Accurate diagnosis of malaria infection during pregnancy remains challenging because of low parasite densities and placental sequestration of Plasmodium falciparum. The performance of different methods to detect P. falciparum in pregnancy and the clinical relevance of undetected infections were evaluated.

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The combination of fosmidomycin and clindamycin (F/C) is effective in adults and older children for the treatment of malaria and could be an important alternative to existing artemisinin-based combinations (ACTs) if proven to work in younger children. We conducted an open-label clinical trial to assess the efficacy, safety, and tolerability of F/C for the treatment of uncomplicated P. falciparum malaria in Mozambican children <3 years of age.

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Background: The rate of acquisition of naturally acquired immunity (NAI) against malaria predominantly depends on transmission intensity and age, although disentangling the effects of these is difficult. We used chemoprophylaxis to selectively control exposure to P. falciparum during different periods in infancy and explore the effect of age in the build-up of NAI, measured as risk of clinical malaria.

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Reversing the spread of HIV infection and the incidence of malaria constitute two of the Millenium Development Goals. However, despite recent achievements, both diseases still entail global heath problems. Furthermore, their overlapping geographical distribution raises concerns and challenges for potential immunological, clinical and therapeutic interactions.

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Uncontrolled endoplasmic reticulum (ER) stress responses are proposed to contribute to the pathology of chronic inflammatory diseases such as type 2 diabetes or atherosclerosis. However, the connection between ER stress and inflammation remains largely unexplored. Here, we show that ER stress causes activation of the NLRP3 inflammasome, with subsequent release of the pro-inflammatory cytokine interleukin-1β.

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Background: Plasmodium falciparum infection in pregnancy can lead to congenital malaria, which has detrimental health consequences for infants. Human immunodeficiency virus (HIV) might increase cord blood P. falciparum infection by decreasing maternal antimalarial-specific antibodies.

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Plasmodium falciparum blood-stage antigens such as merozoite surface protein 1 (MSP-1), apical membrane antigen 1 (AMA-1), and the 175-kDa erythrocyte binding antigen (EBA-175) are considered important targets of naturally acquired immunity to malaria. However, it is not clear whether antibodies to these antigens are effectors in protection against clinical disease or mere markers of exposure. In the context of a randomized, placebo-controlled trial of intermittent preventive treatment in infants conducted between 2002 and 2004, antibody responses to Plasmodium falciparum blood-stage antigens in a cohort of 302 Mozambican children were evaluated by immunofluorescence antibody test and enzyme-linked immunosorbent assay at 5, 9, 12, and 24 months of age.

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Background: Partial protective efficacy lasting up to 43 months after vaccination with the RTS,S malaria vaccine has been reported in one cohort (C1) of a Phase IIb trial in Mozambique, but waning efficacy was observed in a smaller contemporaneous cohort (C2). We hypothesized that low dose exposure to asexual stage parasites resulting from partial pre-erythrocytic protection afforded by RTS,S may contribute to long-term vaccine efficacy to clinical disease, which was not observed in C2 due to intense active detection of infection and treatment.

Methodology/principal Findings: Serum collected 6 months post-vaccination was screened for antibodies to asexual blood stage antigens AMA-1, MSP-1(42), EBA-175, DBL-α and variant surface antigens of the R29 laboratory strain (VSA(R29)).

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A large proportion of the death toll associated with malaria is a consequence of malaria infection during pregnancy, causing up to 200,000 infant deaths annually. We previously published the first extensive genetic association study of placental malaria infection, and here we extend this analysis considerably, investigating genetic variation in over 9,000 SNPs in more than 1,000 genes involved in immunity and inflammation for their involvement in susceptibility to placental malaria infection. We applied a new approach incorporating results from both single gene analysis as well as gene-gene interactions on a protein-protein interaction network.

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Background: Increased susceptibility to Plasmodium falciparum infection during pregnancy has been attributed to the accumulation of infected erythrocytes in the placenta. This phenomenon is mediated by a var gene coding for VAR2CSA, which adheres to chondroitin sulphate A. However, the contribution of parasites transcribing other var genes to maternal infections has not been well characterized.

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Objectives: The aims of this study were to determine the outcomes and predictors of renal disease progression in Puerto Ricans with systemic lupus erythematosus (SLE) initially presenting mild renal involvement.

Methods: A retrospective cohort of 61 patients with SLE (per American College of Rheumatology classification) with mild renal involvement was studied. Mild renal disease was defined as glomerular filtration rate (GFR) of 90 mL/min or higher in the presence of proteinuria (>0.

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Introduction: Severe malaria has been attributed partly to the sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the microvasculature of vital host organs. Identification of P. falciparum cytoadherence phenotypes that are associated with severe malaria may lead to the development of novel strategies against life-threatening malaria.

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Highly active antiretroviral therapy (HAART) significantly reduced the toxoplasmic encephalitis (TE) incidence in acquired immunodeficiency syndrome (AIDS) patients. The TE incidence and mortality were evaluated in an AIDS cohort followed in Puerto Rico before, during, and after HAART implementation in the Island. Of the 2,431 AIDS studied patients 10.

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Women are at higher risk of Plasmodium falciparum infection when pregnant. The decreasing risk of malaria with subsequent pregnancies is attributed to parity-dependent acquisition of antibodies against placental parasites expressing variant surface antigens, VAR2CSA, that mediate placental sequestration through adhesion to chondroitin sulfate A (CSA). However, modulation of immunity during pregnancy may also contribute to increase the risk of malaria.

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