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Abstract The organization and mining of malaria genomic and post-genomic data is important to significantly increase the knowledge of the biology of its causative agents, and is motivated, on a longer term, by the necessity to predict and characterize new biological targets and new drugs. Biological targets are sought in a biological space designed from the genomic data from Plasmodium falciparum, but using also the millions of genomic data from other species. Drug candidates are sought in a chemical space containing the millions of small molecules stored in public and private chemolibraries. Data management should, therefore, be as reliable and versatile as possible. In this context, five aspects of the organization and mining of malaria genomic and post-genomic data were examined: 1) the comparison of protein sequences including compositionally atypical malaria sequences, 2) the high throughput reconstruction of molecular phylogenies, 3) the representation of biological processes, particularly metabolic pathways, 4) the versatile methods to integrate genomic data, biological representations and functional profiling obtained from X-omic experiments after drug treatments and 5) the determination and prediction of protein structures and their molecular docking with drug candidate structures. Recent progress towards a grid-enabled chemogenomic knowledge space is discussed.

Background: Carbapenemase-producing Enterobacteriaceae (CPE) represent an increasing threat to public health, especially in hospitals., Objectives: To investigate an outbreak of CPE in a thoracic-oncology unit by using whole genome sequencing (WGS) and to describe the control measures taken to limit the epidemic, including fecal microbiota transplantation (FMT)., Methods: A retrospective study between December 2016 and October 2017 was performed to investigate an outbreak of CPE in a thoracic-oncology unit at the North Hospital in Marseille, France. The isolates were identified, and antimicrobial susceptibility tests were performed. All CPE were sequenced using MiSeq and/or MinIon technologies. Nucleotide variations between plasmids and similarity within the same species were investigated. The origin of this outbreak, its spread, and the decolonization of patients in the ward were also studied., Results: Four Citrobacter freundii , one Enterobacter cloacae and four E. hormaechei OXA-48 carbapenemase producers were isolated in eight patients hospitalized the same year in a thoracic-oncology ward. The bla OXA-48 gene was present in a Tn 1999.2 transposon located in IncL/M plasmids, with single nucleotide variants (SNV) ranging from 0 to 5. All C. freundii strains belonged to the same ST22 and had more than 99.6% similarity between them. Two strains of E. hormaechei ST1007 were almost identical at 99.98%, while the others belonged to a different ST (ST98, ST114, ST133). No single source was identified. FMT resulted in decolonization in 4/6 patients., Conclusions: WGS demonstrated the dissemination of the bla OXA-48 gene by both clonal ( C. freundii ST22 and E. hormaechei ST1007) and plasmid spread (pOXA-48 IncL/M). The origin of this outbreak appeared to be both external and internal to the ward. This evidence of cross-infection supports the urgent need for the implementation of infection control measures to prevent CPE dissemination., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hadjadj, Cassir, Saïdani, Hoffman, Brouqui, Astoul, Rolain and Baron.)

Delivery of parenteral antimicrobials in non-inpatient settings (DPANS) may be through a dedicated outpatient parenteral antimicrobial therapy (OPAT) service, co-ordinated by hospital- or community-based specialised teams, or via an infusion service involving community-based health professionals (nurses, general practitioners) without centralised hospital oversight, or through ad hoc arrangements. DPANS varies among countries. Our objective was to describe how DPANS is organised at a national level in European countries. A survey (65-item self-administered questionnaire) was conducted from February-June 2019 among infection specialists in 34 European countries on behalf of the ESCMID Study Group for Antimicrobial Stewardship (ESGAP) and the British Society for Antimicrobial Chemotherapy (BSAC) OPAT initiative. Most countries (28/34; 82.4%) participated in the survey. DPANS was available in almost all (27/28; 96.4%) responding countries. DPANS was predominantly provided either via specialised OPAT services (17/28; 60.7%) or via infusion services (16/28; 57.1%), with 11 countries (39.3%) providing both services. A formal OPAT team structure with specifically trained staff was reported in only six countries (6/17; 35.3%). Some countries (4/28; 14.3%) had no structured services but practiced DPANS via ad hoc arrangements. The costs of all stages of the process were covered for patients managed by specialised OPAT/infusion services, either completely, partially or for specific patient groups in the majority (20/28; 71.4%) of countries. The main barriers to implement OPAT/infusion services were lack of organisational structure or guidelines. In conclusion, DPANS with respect to availability and organisation is highly heterogeneous in Europe. National/European guidelines may help improve and standardise DPANS., (Copyright © 2022 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.)

Patients with cancer are at higher risk of severe coronavirus infectious disease 2019 (COVID-19), but the mechanisms underlying virus-host interactions during cancer therapies remain elusive. When comparing nasopharyngeal swabs from cancer and noncancer patients for RT-qPCR cycle thresholds measuring acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in 1063 patients (58% with cancer), we found that malignant disease favors the magnitude and duration of viral RNA shedding concomitant with prolonged serum elevations of type 1 IFN that anticorrelated with anti-RBD IgG antibodies. Cancer patients with a prolonged SARS-CoV-2 RNA detection exhibited the typical immunopathology of severe COVID-19 at the early phase of infection including circulation of immature neutrophils, depletion of nonconventional monocytes, and a general lymphopenia that, however, was accompanied by a rise in plasmablasts, activated follicular T-helper cells, and non-naive Granzyme B + FasL + , Eomes high TCF-1 high , PD-1 + CD8 + Tc1 cells. Virus-induced lymphopenia worsened cancer-associated lymphocyte loss, and low lymphocyte counts correlated with chronic SARS-CoV-2 RNA shedding, COVID-19 severity, and a higher risk of cancer-related death in the first and second surge of the pandemic. Lymphocyte loss correlated with significant changes in metabolites from the polyamine and biliary salt pathways as well as increased blood DNA from Enterobacteriaceae and Micrococcaceae gut family members in long-term viral carriers. We surmise that cancer therapies may exacerbate the paradoxical association between lymphopenia and COVID-19-related immunopathology, and that the prevention of COVID-19-induced lymphocyte loss may reduce cancer-associated death., (© 2021. The Author(s).)

Background: Colonisation with carbapenemase-producing Enterobacteriaceae or Acinetobacter (CPE/A) is associated with complex medical care requiring implementation of specific isolation policies and limitation of patient discharge to other medical facilities. Faecal microbiota transplantation (FMT) has been proposed in order to reduce the duration of gut colonisation., Objectives: This study investigated whether a dedicated protocol of FMT could reduce the negativation time of CPE/A intestinal carriage in patients whose medical care has been delayed due to such colonisation., Method: A matched case-control retrospective study between patients who received FMT treatment and those who did not among CPE/A-colonised patients addressed for initial clustering at the current institute. The study adjusted two controls per case based on sex, age, bacterial species, and carbapenemase type. The primary outcome was delay in negativation of rectal-swab cultures., Results: At day 14 post FMT, 8/10 (80%) treated patients were cleared for intestinal CPE/A carriage. In the control group, 2/20 (10%) had spontaneous clearance at day 14 after CPE/A diagnosis. Faecal microbiota transplantation led patients to reduce the delay in decolonisation (median 3 days post FMT for treated patients vs. 50.5 days after the first documentation of digestive carriage for control patients) and discharge from hospital (median 19.5 days post FMT for treated patients vs. 41 for control patients)., Conclusion: Faecal microbiota transplantation is a safe and time-saving procedure to discharge CPE/A-colonised patients from the hospital. A standardised protocol, including 5 days of antibiotic treatment, bowel cleansing and systematic indwelling devices removal, should improve protocol effectiveness., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Increasing numbers of sporadic cases of melioidosis in returning travelers have been reported from non-endemic regions., Methods: We report a new case and undertook a literature review., Results: Eighty-two travelers with melioidosis infection were included. The mean age was 50.95 years, with only one case <15 years. A male predominance was noted, with 66 males (80.5%). Type of travel included tourism (51.2%), family visits (15.8%) and business (14.6%). The most common destinations were Asia (80.5%), America (9.7%) and Africa (7.3%). No cases were documented from Oceania. Underlying conditions were documented in 68 patients, showing a strong association with diabetes (37.8%). Exposure risks were documented in 32 patients, including contact with water. Pulmonary involvement was seen in 41 patients, cutaneous in 23, abdominal in 14, and urogenital in 10 cases. Blood cultures posed the diagnosis in 43 cases. Fifty-seven patients fully recovered, 12 died, and three relapsed. The mortality rate (14.6%) was close to that observed in Australia but lower than series in Southern Asia., Conclusion: Melioidosis should not only be considered in travelers returning from classically considered endemic areas (Australia and South-East Asia) but also from America and Africa, especially in diabetic patients or after contact with water., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A piperidinyl-benzimidazolone scaffold has been found in the structure of different inhibitors of membrane glycerolipid metabolism, acting on enzymes manipulating diacylglycerol and phosphatidic acid. Screening a focus library of piperidinyl-benzimidazolone analogs might therefore identify compounds acting against infectious parasites. We first evaluated the in vitro effects of (S)-2-(dibenzylamino)-3-phenylpropyl 4-(1,2-dihydro-2-oxobenzo[d]imidazol-3-yl)piperidine-1-carboxylate (compound 1) on Toxoplasma gondii and Plasmodium falciparum. In T. gondii, motility and apical complex integrity appeared to be unaffected, whereas cell division was inhibited at compound 1 concentrations in the micromolar range. In P. falciparum, the proliferation of erythrocytic stages was inhibited, without any delayed death phenotype. We then explored a library of 250 analogs in two steps. We selected 114 compounds with a 50% inhibitory concentration (IC50) cutoff of 2 μM for at least one species and determined in vitro selectivity indexes (SI) based on toxicity against K-562 human cells. We identified compounds with high gains in the IC50 (in the 100 nM range) and SI (up to 1,000 to 2,000) values. Isobole analyses of two of the most active compounds against P. falciparum indicated that their interactions with artemisinin were additive. Here, we propose the use of structure-activity relationship (SAR) models, which will be useful for designing probes to identify the target compound(s) and optimizations for monotherapy or combined-therapy strategies.

Monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) are the main lipids in photosynthetic membranes in plant cells. They are synthesized in the envelope surrounding plastids by MGD and DGD galactosyltransferases. These galactolipids are critical for the biogenesis of photosynthetic membranes, and they act as a source of polyunsaturated fatty acids for the whole cell and as phospholipid surrogates in phosphate shortage. Based on a high-throughput chemical screen, we have characterized a new compound, galvestine-1, that inhibits MGDs in vitro by competing with diacylglycerol binding. Consistent effects of galvestine-1 on Arabidopsis thaliana include root uptake, circulation in the xylem and mesophyll, inhibition of MGDs in vivo causing a reduction of MGDG content and impairment of chloroplast development. The effects on pollen germination shed light on the contribution of galactolipids to pollen-tube elongation. The whole-genome transcriptional response of Arabidopsis points to the potential benefits of galvestine-1 as a unique tool to study lipid homeostasis in plants.

In medical sciences, a target is a broad concept to qualify a biological entity and/or a biological phenomenon, on which one aims to act as part of a therapy. It follows that a target can be defined as a phenotype, a biological process, a subcellular organelle, a protein or a protein domain. It also follows that a target cannot be defined independently of the type of intervention one considers implementing. In this brief review, we describe how in silico organization of genomic and post-genomic information of all partners involved in malaria (human patient, Plasmodium parasite and Anopheles vector), complying with knowledge of the disease in etiologic terms, appears as an efficient source of information not only to help selecting but also discarding target candidates. Some limitations in our capacity to explore the stored biological information, due to the current quality of genomic annotation, level of database integration, or to the performances of existing analytic and mining tools, are discussed. In silico strategies to assess the feasibility of bringing a target to a therapeutic development pipeline, in terms of target "druggability", are introduced.

We report the design, synthesis, and in vitro evaluation of novel polyspirocyclic structures, inspired by the antimalarial natural products, the aculeatins. A divergent synthetic strategy was conceived for the practical supply and has allowed the discovery of two novel and more potent analogues active on the Plasmodium falciparum 3D7 strain. Moreover, these compounds proved to be potent against Toxoplasma gondii. A number of features that govern these inhibitions were identified.

Toxoplasma gondii is a unicellular parasite characterized by unique extracellular and intracellular membrane compartments. The lipid composition of subcellular membranes has not been determined, limiting our understanding of lipid homeostasis, control, and trafficking, a series of processes involved in pathogenesis. In addition to a mitochondrion, Toxoplasma contains a plastid called the apicoplast. The occurrence of a plastid raised the question of the presence of chloroplast galactolipids. Using three independent rabbit and rat antibodies against digalactosyldiacylglycerol (DGDG) from plant chloroplasts, we detected a class of Toxoplasma lipids harboring a digalactolipid-like epitope (DGLE). Immunolabeling characterization supports the notion that the DGLE polar head is similar to that of DGDG. Mass spectrometry analyses indicated that dihexosyl lipids having various hydrophobic moieties (ceramide, diacylglycerol, and acylalkylglycerol) might react with anti-DGDG, but we cannot exclude the possibility that more complex dihexosyl-terminated lipids might also be immunolabeled. DGLE localization was analyzed by immunofluorescence and immunoelectron microscopy and confirmed by subcellular fractionation. No immunolabeling of the apicoplast could be observed. DGLE was scattered in pellicle membrane domains in extracellular tachyzoites and was relocalized to the anterior tip of the cell upon invasion in an actin-dependent manner, providing insights on a possible role in pathogenetic processes. DGLE was detected in other Apicomplexa (i.e., Neospora, Plasmodium, Babesia, and Cryptosporidium).

The organization and mining of malaria genomic and post-genomic data is important to significantly increase the knowledge of the biology of its causative agents, and is motivated, on a longer term, by the necessity to predict and characterize new biological targets and new drugs. Biological targets are sought in a biological space designed from the genomic data from Plasmodium falciparum, but using also the millions of genomic data from other species. Drug candidates are sought in a chemical space containing the millions of small molecules stored in public and private chemolibraries. Data management should, therefore, be as reliable and versatile as possible. In this context, five aspects of the organization and mining of malaria genomic and post-genomic data were examined: 1) the comparison of protein sequences including compositionally atypical malaria sequences, 2) the high throughput reconstruction of molecular phylogenies, 3) the representation of biological processes, particularly metabolic pathways, 4) the versatile methods to integrate genomic data, biological representations and functional profiling obtained from X-omic experiments after drug treatments and 5) the determination and prediction of protein structures and their molecular docking with drug candidate structures. Recent progress towards a grid-enabled chemogenomic knowledge space is discussed.

There is a growing family of novel GTPases conserved among higher plants and vertebrates, abbreviated as AIG1, IAP, IMAP, and IAN, respectively. Here, we comparatively analyze the human gene family encoding GTPases of the immunity-associated protein family recently re-termed GIMAP. Chromosome 7q36.1 contains, within 300 kb, a gimap gene cluster with seven functional genes and one pseudogene (hgimap3). The six genes hgimap1, hgimap2, hgimap4, hgimap5, hgimap6, and hgimap7 encode 33-46 kDa proteins with one GTP-binding domain, whereas hgimap8 encodes a very unusual 75-kDa protein with three GTP-binding domains. All hgimap genes except hgimap2 have orthologs in the mouse. Major expression sites of hgimap mRNAs are the spleen and lymph nodes, but also other organs such as muscle, heart, placenta, and digestive tract display detectable hgimap mRNA levels. The proteins hGIMAP4 and hGIMAP7 can be localized at ER and Golgi apparatus, but not in mitochondria, lysosomes and nuclei. All hgimap genes were expressed at very low levels-if at all-in diverse cancer cell lines. Our data support the view that the GIMAP proteins are involved in the control of cell survival not only in cells of the immune system as commonly anticipated.