19 research outputs found

    Country-wide assessment of the genetic polymorphism in Plasmodium falciparum and Plasmodium vivax antigens detected with rapid diagnostic tests for malaria

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    <p>Abstract</p> <p>Background</p> <p>Rapid diagnostic tests (RDTs) are becoming increasingly indispensable in malaria management, as a means of increasing the accuracy of diagnosis. The WHO has issued recommendations, but the selection of the most suitable RDT remains difficult for users in endemic countries. The genetic variability of the antigens detected with RDTs has been little studied, but may affect the sensitivity of RDTs. This factor has been studied by comparisons between countries at continental level, but little information is available concerning antigen variability within a given country.</p> <p>Methods</p> <p>A country-wide assessment of polymorphism of the PfHRP2, PfHRP3, pLDH and aldolase antigens was carried out in 260 <it>Plasmodium falciparum </it>and 127 <it>Plasmodium vivax </it>isolates, by sequencing the genes encoding these antigens in parasites originating from the various epidemiological strata for malaria in Madagascar.</p> <p>Results</p> <p>Higher levels of polymorphism were observed for the <it>pfhrp2 </it>and <it>pfhrp3 </it>genes than for the <it>P. falciparum </it>and <it>P. vivax aldolase </it>and <it>pldh </it>genes. <it>Pfhrp2 </it>sequence analysis predicted that 9% of Malagasy isolates would not be detected at parasite densities ≤ 250 parasites/μl (ranging from 6% in the north to 14% in the south), although RDTs based on PfHRP2 detection are now recommended in Madagascar.</p> <p>Conclusion</p> <p>These findings highlight the importance of training of health workers and the end users of RDTs in the provision of information about the possibility of false-negative results for patients with clinical symptoms of malaria, particularly in the south of Madagascar.</p

    Low Percentage of Signal Regulatory Protein α/β+ Memory B Cells in Blood Predicts Development of Anti-drug Antibodies (ADA) in Adalimumab-Treated Rheumatoid Arthritis Patients

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    An important goal for personalized treatment is predicting response to a particular therapeutic. A drawback of biological treatment is immunogenicity and the development of antibodies directed against the drug [anti-drug antibodies (ADA)], which are associated with a poorer clinical outcome. Here we set out to identify a predictive biomarker that discriminates rheumatoid arthritis (RA) patients who are more likely to develop ADA in response to adalimumab, a human monoclonal antibody against tumor necrosis factor (TNF)α. By taking advantage of an immune-phenotyping platform, LEGENDScreen™, we measured the expression of 332 cell surface markers on B and T cells in a cross-sectional adalimumab-treated RA patient cohort with a defined ADA response. The analysis revealed seven differentially expressed markers (DEMs) between the ADA+ and ADA− patients. Validation of the DEMs in an independent prospective European cohort of adalimumab treated RA patients, revealed a significant and consistent reduced frequency of signal regulatory protein (SIRP)α/β-expressing memory B cells in ADA+ vs. ADA− RA patients. We also assessed the predictive value of SIRPα/β expression in a longitudinal RA cohort prior to the initiation of adalimumab treatment. We show that a frequency of &lt; 9.4% of SIRPα/β-expressing memory B cells predicts patients that will develop ADA, and consequentially fail to respond to treatment, with a receiver operating characteristic (ROC) area under the curve (AUC) score of 0.92. Thus, measuring the frequency of SIRPα/β-expressing memory B cells in patients prior to adalimumab treatment may be clinically useful to identify a subgroup of active RA subjects who are going to develop an ADA response and not gain substantial clinical benefit from this treatment

    Risk factors for Coronavirus disease 2019 (Covid-19) death in a population cohort study from the Western Cape province, South Africa

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    Risk factors for coronavirus disease 2019 (COVID-19) death in sub-Saharan Africa and the effects of human immunodeficiency virus (HIV) and tuberculosis on COVID-19 outcomes are unknown. We conducted a population cohort study using linked data from adults attending public-sector health facilities in the Western Cape, South Africa. We used Cox proportional hazards models, adjusted for age, sex, location, and comorbidities, to examine the associations between HIV, tuberculosis, and COVID-19 death from 1 March to 9 June 2020 among (1) public-sector “active patients” (≥1 visit in the 3 years before March 2020); (2) laboratory-diagnosed COVID-19 cases; and (3) hospitalized COVID-19 cases. We calculated the standardized mortality ratio (SMR) for COVID-19, comparing adults living with and without HIV using modeled population estimates.Among 3 460 932 patients (16% living with HIV), 22 308 were diagnosed with COVID-19, of whom 625 died. COVID19 death was associated with male sex, increasing age, diabetes, hypertension, and chronic kidney disease. HIV was associated with COVID-19 mortality (adjusted hazard ratio [aHR], 2.14; 95% confidence interval [CI], 1.70–2.70), with similar risks across strata of viral loads and immunosuppression. Current and previous diagnoses of tuberculosis were associated with COVID-19 death (aHR, 2.70 [95% CI, 1.81–4.04] and 1.51 [95% CI, 1.18–1.93], respectively). The SMR for COVID-19 death associated with HIV was 2.39 (95% CI, 1.96–2.86); population attributable fraction 8.5% (95% CI, 6.1–11.1)

    Avaliação da sensibilidade oral em crianças com oclusão normal e maloclusão na dentição mista e início da permanente

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    O objetivo deste trabalho foi avaliar a sensibilidade oral por meio do índice de estereognose oral (hos) em crianças de ambos os sexos, entre 8 e 12 anos de idade com normoclusão ou maloclusão. Para tanto, foram selecionadas 50 crianças, de ambos os sexos, nas fases da dentição mista e início da dentição permanente. Após avaliação clínica as crianças foram divididas em grupos de acordo com as características morfológicas da oclusão: oclusão normal ou maloclusão. A sensibilidade oral foi avaliada pelo índice de estereognose oral, no qual utilizamos peças testes que compreenderam 10 formatos de figuras (círculos, semicírculos, quadrados, retângulos e triângulos em tamanhos pequeno e grande (12x12x3 mm, 8x8x2 mm, respectivamente). Os sujeitos foram classificados quanto ao padrão facial pela fotometria. As variáveis foram analisadas através de estatística descritiva e quantitativa (análise multivariada), e, então, correlacionadas através dos coeficientes de Pearson ou Spearman. As variáveis qualitativas foram associadas às outras variáveis através de testes não paramétricos. Sendo o nível de significância de 0,05% ou p<0,05

    Detection of Legionella Anisa in Water from Hospital Dental Chair Units and Molecular Characterization by Whole-Genome Sequencing

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    International audienceThis study aims to assess contamination with Legionella spp. in water from dental chair units (DCUs) of a hospital dental ward and to perform its molecular characterization by whole-genome sequencing (WGS). We collect eight water samples (250 mL) from four DCUs (sink and water-syringe). Samples are tested for the presence of Legionella spp. (CFUs/mL) by culturing according to the Nederland Norm (NEN) 6265. Three DCUs are found positive for Legionella anisa, and four isolates are cultured (sink n = 2, water-syringe n = 1; two isolates from the same chair) with 1 \texttimes 10\texttwosuperior CFU/mL. Whole-genome multi-locus sequence typing (wgMLST) results indicate that all strains belong to the same cluster with two to four allele differences. Classical culture combined with WGS allows the identification of a unique clone of L. anisa in several DCUs in the same hospital dental ward. This may indicate a common contamination source in the dental unit waterlines, which was fixed by replacing the chairs and main pipeline of the unit. Our results reveal tap water contamination in direct contact with patients and the usefulness of WGS to investigate bacterial molecular epidemiology

    Low Percentage of Signal Regulatory Protein α/β+ Memory B Cells in Blood Predicts Development of Anti-drug Antibodies (ADA) in Adalimumab-Treated Rheumatoid Arthritis Patients

    No full text
    An important goal for personalized treatment is predicting response to a particular therapeutic. A drawback of biological treatment is immunogenicity and the development of antibodies directed against the drug [anti-drug antibodies (ADA)], which are associated with a poorer clinical outcome. Here we set out to identify a predictive biomarker that discriminates rheumatoid arthritis (RA) patients who are more likely to develop ADA in response to adalimumab, a human monoclonal antibody against tumor necrosis factor (TNF)α. By taking advantage of an immune-phenotyping platform, LEGENDScreen™, we measured the expression of 332 cell surface markers on B and T cells in a cross-sectional adalimumab-treated RA patient cohort with a defined ADA response. The analysis revealed seven differentially expressed markers (DEMs) between the ADA+ and ADA- patients. Validation of the DEMs in an independent prospective European cohort of adalimumab treated RA patients, revealed a significant and consistent reduced frequency of signal regulatory protein (SIRP)α/β-expressing memory B cells in ADA+ vs. ADA- RA patients. We also assessed the predictive value of SIRPα/β expression in a longitudinal RA cohort prior to the initiation of adalimumab treatment. We show that a frequency of < 9.4% of SIRPα/β-expressing memory B cells predicts patients that will develop ADA, and consequentially fail to respond to treatment, with a receiver operating characteristic (ROC) area under the curve (AUC) score of 0.92. Thus, measuring the frequency of SIRPα/β-expressing memory B cells in patients prior to adalimumab treatment may be clinically useful to identify a subgroup of active RA subjects who are going to develop an ADA response and not gain substantial clinical benefit from this treatment

    Differentiation-dependent susceptibility of human muscle cells to Zika virus infection

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    International audienceMuscle cells are potential targets of many arboviruses, such as Ross River, Dengue, Sindbis, and chikungunya viruses, that may be involved in the physiopathological course of the infection. During the recent outbreak of Zika virus (ZIKV), myalgia was one of the most frequently reported symptoms. We investigated the susceptibility of human muscle cells to ZIKV infection. Using an in vitro model of human primary myoblasts that can be differentiated into myotubes, we found that myoblasts can be productively infected by ZIKV. In contrast, myotubes were shown to be resistant to ZIKV infection, suggesting a differentiation-dependent susceptibility. Infection was accompanied by a caspase-independent cytopathic effect, associated with paraptosis-like cytoplasmic vacuolization. Proteomic profiling was performed 24h and 48h post-infection in cells infected with two different isolates. Proteome changes indicate that ZIKV infection induces an upregulation of proteins involved in the activation of the Interferon type I pathway, and a downregulation of protein synthesis. This work constitutes the first observation of primary human muscle cells susceptibility to ZIKV infection, and differentiation-dependent restriction of infection from myoblasts to myotubes. Since myoblasts constitute the reservoir of stem cells involved in reparation/regeneration in muscle tissue, the infection of muscle cells and the viral-induced alterations observed here could have consequences in ZIKV infection pathogenesis

    Long-term quality of life among localised prostate cancer survivors: QALIPRO population-based study

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    International audienceBackgroundTo evaluate quality of life (QoL) 10 years after treatments for localised prostate cancer (LPCa) patients in comparison with aged-matched healthy controls.MethodsLPCa patients diagnosed in 2001 were obtained from 11 French cancer registries. Controls were recruited among the general population and were matched to patients on age and geographic area. EORTC Quality of Life Questionnaire – Core 30 items, Expanded Prostate Cancer Index Composite, Hospital Anxiety and Depression Scale and Multidimensional Fatigue Inventory self-reported questionnaires were used to measure QoL, anxiety and fatigue. Patients were classified in three groups according to previous treatments: radical prostatectomy (RP), radiotherapy (RT) and radical prostatectomy and radiotherapy (RP+RT). The differences in QoL between patients and controls and according to treatment groups were evaluated.ResultsThere were 287 patients and 287 controls. There was no socio-demographic difference between patients and controls. Treatments were: RP (143), RT (78), PR+RT (33), baseline hormone therapy (49) and hormone therapy at the time of the study (34). Patients had similar levels of global QoL, anxiety, depression and fatigue as controls. They reported more urinary troubles (urinary function and incontinence) (p < 0.0001) and more sexual dysfunctions (p < 0.0001) than controls, whatever the treatment group. Worse bowel dysfunction was reported in patients treated by RT and RP+RT (p < 0.002). According to the treatments, RP groups had the worst urinary function and incontinence (p < 0.01), and reported more bowel bother when the treatment was combined with RT.ConclusionsEven though patients reported similar global QoL as control 10 years after treatment, patients reported numerous urinary and sexual dysfunctions. Patients treated with RP+RT reported cumulative sequelae of both treatments
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