Simultaneous gene expression profiling in human macrophages infected with Leishmania major parasites using SAGE

<p>Abstract</p> <p>Background</p> <p><it>Leishmania </it>(<it>L</it>) are intracellular protozoan parasites that are able to survive and replicate within the harsh and potentially hostile phagolysosomal environment of mammalian mononuclear phagocytes. A complex interplay then takes place between the macrophage (MΦ) striving to eliminate the pathogen and the parasite struggling for its own survival.</p> <p>To investigate this host-parasite conflict at the transcriptional level, in the context of monocyte-derived human MΦs (MDM) infection by <it>L. major </it>metacyclic promastigotes, the quantitative technique of serial analysis of gene expression (SAGE) was used.</p> <p>Results</p> <p>After extracting mRNA from resting human MΦs, <it>Leishmania</it>-infected human MΦs and <it>L. major </it>parasites, three SAGE libraries were constructed and sequenced generating up to 28,173; 57,514 and 33,906 tags respectively (corresponding to 12,946; 23,442 and 9,530 unique tags). Using computational data analysis and direct comparison to 357,888 publicly available experimental human tags, the parasite and the host cell transcriptomes were then simultaneously characterized from the mixed cellular extract, confidently discriminating host from parasite transcripts. This procedure led us to reliably assign 3,814 tags to MΦs' and 3,666 tags to <it>L. major </it>parasites transcripts. We focused on these, showing significant changes in their expression that are likely to be relevant to the pathogenesis of parasite infection: (i) human MΦs genes, belonging to key immune response proteins (e.g., IFNγ pathway, S100 and chemokine families) and (ii) a group of <it>Leishmania </it>genes showing a preferential expression at the parasite's intra-cellular developing stage.</p> <p>Conclusion</p> <p>Dual SAGE transcriptome analysis provided a useful, powerful and accurate approach to discriminating genes of human or parasitic origin in <it>Leishmania</it>-infected human MΦs. The findings presented in this work suggest that the <it>Leishmania </it>parasite modulates key transcripts in human MΦs that may be beneficial for its establishment and survival. Furthermore, these results provide an overview of gene expression at two developmental stages of the parasite, namely metacyclic promastigotes and intracellular amastigotes and indicate a broad difference between their transcriptomic profiles. Finally, our reported set of expressed genes will be useful in future rounds of data mining and gene annotation.</p

The Self-Assessment Scale of Cognitive Complaints in Schizophrenia: A validation study in Tunisian population

<p>Abstract</p> <p>Background</p> <p>Despite a huge well-documented literature on cognitive deficits in schizophrenia, little is known about the own perception of patients regarding their cognitive functioning. The purpose of our study was to create a scale to collect subjective cognitive complaints of patients suffering from schizophrenia with Tunisian Arabic dialect as mother tongue and to proceed to a validation study of this scale.</p> <p>Methods</p> <p>The authors constructed the Self-Assessment Scale of Cognitive Complaints in Schizophrenia (SASCCS) based on a questionnaire covering five cognitive domains which are the most frequently reported in the literature to be impaired in schizophrenia. The scale consisted of 21 likert-type questions dealing with memory, attention, executive functions, language and praxia. In a second time, the authors proceeded to the study of psychometric qualities of the scale among 105 patients suffering from schizophrenia spectrum disorders (based on DSM- IV criteria). Patients were evaluated using the Positive and Negative Syndrome Scale (PANSS), the Global Assessment Functioning Scale (GAF scale) and the Calgary Depression Scale (CDS).</p> <p>Results</p> <p>The scale's reliability was proven to be good through Cronbach alpha coefficient equal to 0.85 and showing its good internal consistency. The intra-class correlation coefficient at 11 weeks was equal to 0.77 suggesting a good stability over time. Principal component analysis with Oblimin rotation was performed and yielded to six factors accounting for 58.28% of the total variance of the scale.</p> <p>Conclusion</p> <p>Given the good psychometric properties that have been revealed in this study, the SASCCS seems to be reliable to measure schizophrenic patients' perception of their own cognitive impairment. This kind of evaluation can't substitute for objective measures of cognitive performances in schizophrenia. The purpose of such an evaluation is to permit to the patient to express his own well-being and satisfaction of quality of life.</p

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

A canine study of immunotherapy in scorpion envenomation

International audienceOBJECTIVE: To evaluate the effects of scorpion venom and antivenom in experimental envenomation.DESIGN: Prospective, controlled animal study.SETTING: University research laboratorySUBJECTS: Twenty-nine anesthetized and ventilated dogs.INTERVENTIONS: The first group of animals had venom alone (0.05 mg/kg). Animals from the second group had simultaneous administration of 10 ml of scorpion antivenom (SAV). In the third and fourth groups, 10 ml and 40 ml SAV, respectively, were injected 10 min following venom.MEASUREMENTS AND RESULTS: Hemodynamic parameters using right heart catheter were recorded and dosage of catecholamines, neuropeptide Y (NPY), endothelin-1, and atrial natriuretic peptide (ANP) were performed at baseline and during 60 min following envenomation. In the control group, at 5 min, there was a sharp increase in pulmonary artery occluded pressure (PAOP, from 2 mmHg to 23 mmHg), mean arterial pressure (MAP, from 125 mmHg to 212 mmHg) and systemic vascular resistance (SVR, from 2450 dyn sec(-1 )m(5) to 5775 dyn sec(-1 )m(5), P<0.05 for all). Heart rate, cardiac output, and stroke volume decreased. There was a 40-fold increase in epinephrine and norepinephrine plasma concentrations. Circulating NPY and ANP dosages increased too. PAOP and MAP decreased thereafter to reach baseline levels. Simultaneous administration of SAV with venom totally offset the hallmarks of scorpion envenomation. Delayed administration of SAV at any dosage failed to alter the features of scorpion envenomation.CONCLUSION: While simultaneous administration of SAV and scorpion venom is effective in preventing scorpion envenomation-related manifestations, delayed administration of SAV, either at standard or elevated dosages, failed to alter any of the scorpion envenomation features

High frequency of exon 15 deletion in the FANCA gene in Tunisian patients affected with Fanconi anemia disease: implication for diagnosis.

International audienceTunisian population is characterized by its heterogeneous ethnic background and high rate of consanguinity. In consequence, there is an increase in the frequency of recessive genetic disorders including Fanconi anemia (FA). The aim of this study was to confirm the existence of a founder haplotype among FA Tunisian patients and to identify the associated mutation in order to develop a simple tool for FA diagnosis. Seventy-four unrelated families with a total of 95 FA patients were investigated. All available family members were genotyped with four microsatellite markers flanking FANCA gene. Haplotype analysis and homozygosity mapping assigned 83 patients belonging to 62 families to the FA-A group. A common haplotype was shared by 42 patients from 26 families at a homozygous state while five patients from five families were heterozygous. Among them, 85% were from southern Tunisia suggesting a founder effect. Using multiplex ligation-dependent probe amplification (MLPA) technique, we have also demonstrated that this haplotype is associated with a total deletion of exon 15 in FANCA gene. Identification of a founder mutation allowed genetic counseling in relatives of these families, better bone marrow graft donor selection and prenatal diagnosis. This mutation should be investigated in priority for patients originating from North Africa and Middle East

Single autologous stem-cell transplantation followed by maintenance therapy with thalidomide is superior to double autologous transplantation in multiple myeloma: results of a multicenter randomized clinical trial (Retracted article. See vol. 113, pg. 6265, 2009)

International audienceFrom April 2003 to December 2006, 195 patients with de novo symptomatic myeloma and younger than 60 years of age were randomly assigned to receive either tandem transplantation up front (arm A, n = 97) or one autologous stem-cell transplantation followed by a maintenance therapy with thalidomide (day + 90, 100 mg per day during 6 months) (arm B, n = 98). Patients included in arm B received a second transplant at disease progression. In both arms, autologous stem-cell transplantation was preceded by first-line therapy with thalidomide-dexamethasone and subsequent collection of peripheral blood stem cells with high-dose cyclophosphamide (4 g/m(2)) and granulocyte colony stimulating factor. Data were analyzed on an intent-to-treat basis. With a median follow-up of 33 months (range, 6-46 months), the 3-year overall survival was 65% in arm A and 85% in arm B (P = .04). The 3-year progression-free survival was 57% in arm A and 85% in arm B (P = .02). Up-front single autologous transplantation followed by 6 months of maintenance therapy with thalidomide (with second transplant in reserve for relapse or progression) is an effective therapeutic strategy to treat multiple myeloma patients and appears superior to tandem transplant in this setting. This study was registered at www.ClinicalTrials.gov as (NCT 00207805)