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  1. Article ; Online: Screening of viral-vectored P. falciparum pre-erythrocytic candidate vaccine antigens using chimeric rodent parasites.

    Kolli, Surendra Kumar / Salman, Ahmed M / Ramesar, Jai / Chevalley-Maurel, Severine / Kroeze, Hans / Geurten, Fiona G A / Miyazaki, Shinya / Mukhopadhyay, Ekta / Marin-Mogollon, Catherin / Franke-Fayard, Blandine / Hill, Adrian V S / Janse, Chris J

    PloS one

    2021  Volume 16, Issue 7, Page(s) e0254498

    Abstract: To screen for additional vaccine candidate antigens of Plasmodium pre-erythrocytic stages, fourteen P. falciparum proteins were selected based on expression in sporozoites or their role in establishment of hepatocyte infection. For preclinical evaluation ...

    Abstract To screen for additional vaccine candidate antigens of Plasmodium pre-erythrocytic stages, fourteen P. falciparum proteins were selected based on expression in sporozoites or their role in establishment of hepatocyte infection. For preclinical evaluation of immunogenicity of these proteins in mice, chimeric P. berghei sporozoites were created that express the P. falciparum proteins in sporozoites as an additional copy gene under control of the uis4 gene promoter. All fourteen chimeric parasites produced sporozoites but sporozoites of eight lines failed to establish a liver infection, indicating a negative impact of these P. falciparum proteins on sporozoite infectivity. Immunogenicity of the other six proteins (SPELD, ETRAMP10.3, SIAP2, SPATR, HT, RPL3) was analyzed by immunization of inbred BALB/c and outbred CD-1 mice with viral-vectored (ChAd63 or ChAdOx1, MVA) vaccines, followed by challenge with chimeric sporozoites. Protective immunogenicity was determined by analyzing parasite liver load and prepatent period of blood stage infection after challenge. Of the six proteins only SPELD immunized mice showed partial protection. We discuss both the low protective immunogenicity of these proteins in the chimeric rodent malaria challenge model and the negative effect on P. berghei sporozoite infectivity of several P. falciparum proteins expressed in the chimeric sporozoites.
    MeSH term(s) Animals ; Antibodies, Protozoan/immunology ; Antibodies, Protozoan/metabolism ; Antigens, Protozoan/immunology ; Antigens, Protozoan/metabolism ; Erythrocytes/metabolism ; Female ; Malaria Vaccines/therapeutic use ; Malaria, Falciparum/genetics ; Malaria, Falciparum/immunology ; Malaria, Falciparum/parasitology ; Mice ; Mice, Inbred BALB C ; Plasmodium falciparum/metabolism ; Plasmodium falciparum/pathogenicity ; Protozoan Proteins/metabolism ; Ribosomal Protein L3 ; Sporozoites/pathogenicity
    Chemical Substances Antibodies, Protozoan ; Antigens, Protozoan ; Malaria Vaccines ; Protozoan Proteins ; Ribosomal Protein L3 ; Rpl3 protein, mouse
    Language English
    Publishing date 2021-07-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0254498
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: ICAM-1 is a key receptor mediating cytoadherence and pathology in the Plasmodium chabaudi malaria model.

    Cunningham, Deirdre A / Lin, Jing-Wen / Brugat, Thibaut / Jarra, William / Tumwine, Irene / Kushinga, Garikai / Ramesar, Jai / Franke-Fayard, Blandine / Langhorne, Jean

    Malaria journal

    2017  Volume 16, Issue 1, Page(s) 185

    Abstract: Background: Parasite cytoadherence within the microvasculature of tissues and organs of infected individuals is implicated in the pathogenesis of several malaria syndromes. Multiple host receptors may mediate sequestration. The identity of the host ... ...

    Abstract Background: Parasite cytoadherence within the microvasculature of tissues and organs of infected individuals is implicated in the pathogenesis of several malaria syndromes. Multiple host receptors may mediate sequestration. The identity of the host receptor(s), or the parasite ligand(s) responsible for sequestration of Plasmodium species other than Plasmodium falciparum is largely unknown. The rodent malaria parasites may be useful to model interactions of parasite species, which lack the var genes with their respective hosts, as other multigene families are shared between the species. The role of the endothelial receptors ICAM-1 and CD36 in cytoadherence and in the development of pathology was investigated in a Plasmodium chabaudi infection in C57BL/6 mice lacking these receptors. The schizont membrane-associated cytoadherence (SMAC) protein of Plasmodium berghei has been shown to exhibit reduced CD36-associated cytoadherence in P. berghei ANKA-infected mice.
    Methods: Parasite tissue sequestration and the development of acute stage pathology in P. chabaudi infections of mice lacking CD36 or ICAM-1, their respective wild type controls, and in infections with mutant P. chabaudi parasites lacking the smac gene were compared. Peripheral blood parasitaemia, red blood cell numbers and weight change were monitored throughout the courses of infection. Imaging of bioluminescent parasites in isolated tissues (spleen, lungs, liver, kidney and gut) was used to measure tissue parasite load.
    Results: This study shows that neither the lack of CD36 nor the deletion of the smac gene from P. chabaudi significantly impacted on acute-stage pathology or parasite sequestration. By contrast, in the absence of ICAM-1, infected animals experience less anaemia and weight loss, reduced parasite accumulation in both spleen and liver and higher peripheral blood parasitaemia during acute stage malaria. The reduction in parasite tissue sequestration in infections of ICAM-1 null mice is maintained after mosquito transmission.
    Conclusions: These results indicate that ICAM-1-mediated cytoadherence is important in the P. chabaudi model of malaria and suggest that for rodent malarias, as for P. falciparum, there may be multiple host and parasite molecules involved in sequestration.
    Language English
    Publishing date 2017-05-03
    Publishing country England
    Document type Journal Article
    ISSN 1475-2875
    ISSN (online) 1475-2875
    DOI 10.1186/s12936-017-1834-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: P. berghei telomerase subunit TERT is essential for parasite survival.

    Religa, Agnieszka A / Ramesar, Jai / Janse, Chris J / Scherf, Artur / Waters, Andrew P

    PloS one

    2014  Volume 9, Issue 9, Page(s) e108930

    Abstract: Telomeres define the ends of chromosomes protecting eukaryotic cells from chromosome instability and eventual cell death. The complex regulation of telomeres involves various proteins including telomerase, which is a specialized ribonucleoprotein ... ...

    Abstract Telomeres define the ends of chromosomes protecting eukaryotic cells from chromosome instability and eventual cell death. The complex regulation of telomeres involves various proteins including telomerase, which is a specialized ribonucleoprotein responsible for telomere maintenance. Telomeres of chromosomes of malaria parasites are kept at a constant length during blood stage proliferation. The 7-bp telomere repeat sequence is universal across different Plasmodium species (GGGTTT/CA), though the average telomere length varies. The catalytic subunit of telomerase, telomerase reverse transcriptase (TERT), is present in all sequenced Plasmodium species and is approximately three times larger than other eukaryotic TERTs. The Plasmodium RNA component of TERT has recently been identified in silico. A strategy to delete the gene encoding TERT via double cross-over (DXO) homologous recombination was undertaken to study the telomerase function in P. berghei. Expression of both TERT and the RNA component (TR) in P. berghei blood stages was analysed by Western blotting and Northern analysis. Average telomere length was measured in several Plasmodium species using Telomere Restriction Fragment (TRF) analysis. TERT and TR were detected in blood stages and an average telomere length of ∼ 950 bp established. Deletion of the tert gene was performed using standard transfection methodologies and we show the presence of tert- mutants in the transfected parasite populations. Cloning of tert- mutants has been attempted multiple times without success. Thorough analysis of the transfected parasite populations and the parasite obtained from extensive parasite cloning from these populations provide evidence for a so called delayed death phenotype as observed in different organisms lacking TERT. The findings indicate that TERT is essential for P. berghei cell survival. The study extends our current knowledge on telomere biology in malaria parasites and validates further investigations to identify telomerase inhibitors to induce parasite cell death.
    MeSH term(s) Amino Acid Sequence ; Animals ; Cell Survival ; Gene Deletion ; Life Cycle Stages ; Mice ; Molecular Sequence Data ; Parasites/cytology ; Parasites/enzymology ; Parasites/growth & development ; Plasmodium berghei/cytology ; Plasmodium berghei/enzymology ; Plasmodium berghei/growth & development ; Protein Subunits/chemistry ; Protein Subunits/genetics ; Protein Subunits/metabolism ; RNA/metabolism ; Telomerase/chemistry ; Telomerase/genetics ; Telomerase/metabolism ; Telomere/metabolism
    Chemical Substances Protein Subunits ; telomerase RNA ; RNA (63231-63-0) ; Telomerase (EC 2.7.7.49)
    Language English
    Publishing date 2014-10-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0108930
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Creation and preclinical evaluation of genetically attenuated malaria parasites arresting growth late in the liver.

    Franke-Fayard, Blandine / Marin-Mogollon, Catherin / Geurten, Fiona J A / Chevalley-Maurel, Séverine / Ramesar, Jai / Kroeze, Hans / Baalbergen, Els / Wessels, Els / Baron, Ludivine / Soulard, Valérie / Martinson, Thomas / Aleshnick, Maya / Huijs, Antonius T G / Subudhi, Amit K / Miyazaki, Yukiko / Othman, Ahmad Syibli / Kolli, Surendra Kumar / Lamers, Olivia A C / Roques, Magali /
    Stanway, Rebecca R / Murphy, Sean C / Foquet, Lander / Moita, Diana / Mendes, António M / Prudêncio, Miguel / Dechering, Koen J / Heussler, Volker T / Pain, Arnab / Wilder, Brandon K / Roestenberg, Meta / Janse, Chris J

    NPJ vaccines

    2022  Volume 7, Issue 1, Page(s) 139

    Abstract: Whole-sporozoite (WSp) malaria vaccines induce protective immune responses in animal malaria models and in humans. A recent clinical trial with a WSp vaccine comprising genetically attenuated parasites (GAP) which arrest growth early in the liver (PfSPZ- ... ...

    Abstract Whole-sporozoite (WSp) malaria vaccines induce protective immune responses in animal malaria models and in humans. A recent clinical trial with a WSp vaccine comprising genetically attenuated parasites (GAP) which arrest growth early in the liver (PfSPZ-GA1), showed that GAPs can be safely administered to humans and immunogenicity is comparable to radiation-attenuated PfSPZ Vaccine. GAPs that arrest late in the liver stage (LA-GAP) have potential for increased potency as shown in rodent malaria models. Here we describe the generation of four putative P. falciparum LA-GAPs, generated by CRISPR/Cas9-mediated gene deletion. One out of four gene-deletion mutants produced sporozoites in sufficient numbers for further preclinical evaluation. This mutant, PfΔmei2, lacking the mei2-like RNA gene, showed late liver growth arrest in human liver-chimeric mice with human erythrocytes, absence of unwanted genetic alterations and sensitivity to antimalarial drugs. These features of PfΔmei2 make it a promising vaccine candidate, supporting further clinical evaluation. PfΔmei2 (GA2) has passed regulatory approval for safety and efficacy testing in humans based on the findings reported in this study.
    Language English
    Publishing date 2022-11-04
    Publishing country England
    Document type Journal Article
    ISSN 2059-0105
    ISSN (online) 2059-0105
    DOI 10.1038/s41541-022-00558-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Malaria parasite evades mosquito immunity by glutaminyl cyclase-mediated posttranslational protein modification.

    Kolli, Surendra Kumar / Molina-Cruz, Alvaro / Araki, Tamasa / Geurten, Fiona J A / Ramesar, Jai / Chevalley-Maurel, Severine / Kroeze, Hans J / Bezemer, Sascha / de Korne, Clarize / Withers, Roxanne / Raytselis, Nadia / El Hebieshy, Angela F / Kim, Robbert Q / Child, Matthew A / Kakuta, Soichiro / Hisaeda, Hajime / Kobayashi, Hirotaka / Annoura, Takeshi / Hensbergen, Paul J /
    Franke-Fayard, Blandine M / Barillas-Mury, Carolina / Scheeren, Ferenc A / Janse, Chris J

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 35, Page(s) e2209729119

    Abstract: Glutaminyl cyclase (QC) modifies N-terminal glutamine or glutamic acid residues of target proteins into cyclic pyroglutamic acid (pGlu). Here, we report the biochemical and functional analysis ... ...

    Abstract Glutaminyl cyclase (QC) modifies N-terminal glutamine or glutamic acid residues of target proteins into cyclic pyroglutamic acid (pGlu). Here, we report the biochemical and functional analysis of
    MeSH term(s) Aminoacyltransferases/immunology ; Animals ; Culicidae/immunology ; Glutamic Acid/metabolism ; Glutamine/metabolism ; Humans ; Malaria/genetics ; Malaria/immunology ; Malaria/parasitology ; Plasmodium berghei/genetics ; Plasmodium berghei/immunology ; Protein Processing, Post-Translational/immunology ; Protozoan Proteins/immunology ; Sporozoites/immunology
    Chemical Substances Protozoan Proteins ; Glutamine (0RH81L854J) ; Glutamic Acid (3KX376GY7L) ; Aminoacyltransferases (EC 2.3.2.-) ; glutaminyl-peptide cyclotransferase (EC 2.3.2.5)
    Language English
    Publishing date 2022-08-22
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Intramural
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2209729119
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  6. Article ; Online: Author Correction: The Plasmodium falciparum male gametocyte protein P230p, a paralog of P230, is vital for ookinete formation and mosquito transmission.

    Marin-Mogollon, Catherin / van de Vegte-Bolmer, Marga / van Gemert, Geert-Jan / van Pul, Fiona J A / Ramesar, Jai / Othman, Ahmad Syibli / Kroeze, Hans / Miao, Jun / Cui, Liwang / Williamson, Kim C / Sauerwein, Robert W / Janse, Chris J / Khan, Shahid M

    Scientific reports

    2019  Volume 9, Issue 1, Page(s) 7061

    Abstract: A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper. ...

    Abstract A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
    Language English
    Publishing date 2019-05-03
    Publishing country England
    Document type Published Erratum
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-019-43505-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: High-efficiency transfection and drug selection of genetically transformed blood stages of the rodent malaria parasite Plasmodium berghei.

    Janse, Chris J / Ramesar, Jai / Waters, Andrew P

    Nature protocols

    2006  Volume 1, Issue 1, Page(s) 346–356

    Abstract: This protocol describes a method of genetic transformation for the rodent malaria parasite Plasmodium berghei with a high transfection efficiency of 10(-3)-10(-4). It provides methods for: (i) in vitro cultivation and purification of the schizont stage;( ... ...

    Abstract This protocol describes a method of genetic transformation for the rodent malaria parasite Plasmodium berghei with a high transfection efficiency of 10(-3)-10(-4). It provides methods for: (i) in vitro cultivation and purification of the schizont stage;(ii) transfection of DNA constructs containing drug-selectable markers into schizonts using the nonviral Nucleofector technology; and (iii) injection of transfected parasites into mice and subsequent selection of mutants by drug treatment in vivo. Drug selection is described for two (antimalarial) drugs, pyrimethamine and WR92210. The drug-selectable markers currently in use are the pyrimethamine-resistant dihydrofolate reductase (dhfr) gene of Plasmodium or Toxoplasma gondii and the DHFR gene of humans that confer resistance to pyrimethamine and WR92210, respectively. This protocol enables the generation of transformed parasites within 10-15 d. Genetic modification of P. berghei is widely used to investigate gene function in Plasmodium, and this protocol for high-efficiency transformation will enable the application of large-scale functional genomics approaches.
    MeSH term(s) Animals ; Antimalarials/pharmacology ; Culture Techniques ; Drug Resistance ; Genetic Markers ; Humans ; Mice ; Mutation ; Plasmodium berghei/drug effects ; Plasmodium berghei/genetics ; Plasmodium berghei/growth & development ; Pyrimethamine/pharmacology ; Tetrahydrofolate Dehydrogenase/genetics ; Transfection/methods ; Transformation, Genetic ; Triazines/pharmacology
    Chemical Substances Antimalarials ; Genetic Markers ; Triazines ; BRL 6231 (47326-86-3) ; Tetrahydrofolate Dehydrogenase (EC 1.5.1.3) ; Pyrimethamine (Z3614QOX8W)
    Language English
    Publishing date 2006
    Publishing country England
    Document type Journal Article
    ZDB-ID 2244966-8
    ISSN 1750-2799 ; 1754-2189
    ISSN (online) 1750-2799
    ISSN 1754-2189
    DOI 10.1038/nprot.2006.53
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  8. Article ; Online: Generation of Novel

    Miyazaki, Shinya / Yang, Annie S P / Geurten, Fiona J A / Marin-Mogollon, Catherin / Miyazaki, Yukiko / Imai, Takashi / Kolli, Surendra Kumar / Ramesar, Jai / Chevalley-Maurel, Severine / Salman, Ahmed M / van Gemert, Geert-Jan A / van Waardenburg, Youri M / Franke-Fayard, Blandine / Hill, Adrian V S / Sauerwein, Robert W / Janse, Chris J / Khan, Shahid M

    Frontiers in cellular and infection microbiology

    2020  Volume 10, Page(s) 270

    Abstract: Transgenic reporter lines of malaria parasites that express fluorescent or luminescent proteins are valuable tools for drug and vaccine screening assays as well as to interrogate parasite gene function. ... ...

    Abstract Transgenic reporter lines of malaria parasites that express fluorescent or luminescent proteins are valuable tools for drug and vaccine screening assays as well as to interrogate parasite gene function. Different
    MeSH term(s) Animals ; Clustered Regularly Interspaced Short Palindromic Repeats ; Culicidae ; Genes, Reporter ; Luciferases/genetics ; Luminescent Proteins/genetics ; Malaria, Falciparum ; Plasmodium falciparum/genetics ; Promoter Regions, Genetic ; Sporozoites
    Chemical Substances Luminescent Proteins ; Luciferases (EC 1.13.12.-)
    Language English
    Publishing date 2020-06-10
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2619676-1
    ISSN 2235-2988 ; 2235-2988
    ISSN (online) 2235-2988
    ISSN 2235-2988
    DOI 10.3389/fcimb.2020.00270
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  9. Article ; Online: Generation of a Genetically Modified Chimeric

    Miyazaki, Yukiko / Marin-Mogollon, Catherin / Imai, Takashi / Mendes, António M / van der Laak, Rianne / Sturm, Angelika / Geurten, Fiona J A / Miyazaki, Shinya / Chevalley-Maurel, Severine / Ramesar, Jai / Kolli, Surendra K / Kroeze, Hans / van Schuijlenburg, Roos / Salman, Ahmed M / Wilder, Brandon K / Reyes-Sandoval, Arturo / Dechering, Koen J / Prudêncio, Miguel / Janse, Chris J /
    Khan, Shahid M / Franke-Fayard, Blandine

    Frontiers in cellular and infection microbiology

    2020  Volume 10, Page(s) 591046

    Abstract: Chimeric rodent malaria parasites with the endogenous circumsporozoite protein ( ...

    Abstract Chimeric rodent malaria parasites with the endogenous circumsporozoite protein (
    MeSH term(s) Animals ; Antibodies, Protozoan ; Malaria ; Malaria Vaccines/genetics ; Malaria, Falciparum/prevention & control ; Mice ; Plasmodium falciparum/genetics ; Plasmodium vivax/genetics ; Protozoan Proteins/genetics
    Chemical Substances Antibodies, Protozoan ; Malaria Vaccines ; Protozoan Proteins
    Language English
    Publishing date 2020-12-17
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2619676-1
    ISSN 2235-2988 ; 2235-2988
    ISSN (online) 2235-2988
    ISSN 2235-2988
    DOI 10.3389/fcimb.2020.591046
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  10. Article ; Online: Protective immunity differs between routes of administration of attenuated malaria parasites independent of parasite liver load.

    Haeberlein, Simone / Chevalley-Maurel, Séverine / Ozir-Fazalalikhan, Arifa / Koppejan, Hester / Winkel, Beatrice M F / Ramesar, Jai / Khan, Shahid M / Sauerwein, Robert W / Roestenberg, Meta / Janse, Chris J / Smits, Hermelijn H / Franke-Fayard, Blandine

    Scientific reports

    2017  Volume 7, Issue 1, Page(s) 10372

    Abstract: In humans and murine models of malaria, intradermal immunization (ID-I) with genetically attenuated sporozoites that arrest in liver induces lower protective immunity than intravenous immunization (IV-I). It is unclear whether this difference is caused ... ...

    Abstract In humans and murine models of malaria, intradermal immunization (ID-I) with genetically attenuated sporozoites that arrest in liver induces lower protective immunity than intravenous immunization (IV-I). It is unclear whether this difference is caused by fewer sporozoites migrating into the liver or by suboptimal hepatic and injection site-dependent immune responses. We therefore developed a Plasmodium yoelii immunization/boost/challenge model to examine parasite liver loads as well as hepatic and lymph node immune responses in protected and unprotected ID-I and IV-I animals. Despite introducing the same numbers of genetically attenuated parasites in the liver, ID-I resulted in lower sterile protection (53-68%) than IV-I (93-95%). Unprotected mice developed less sporozoite-specific CD8
    MeSH term(s) Animals ; CD8-Positive T-Lymphocytes/immunology ; CD8-Positive T-Lymphocytes/metabolism ; Disease Models, Animal ; Humans ; Immunization ; Life Cycle Stages ; Liver/immunology ; Liver/parasitology ; Lymphocyte Count ; Malaria/immunology ; Malaria/parasitology ; Mice ; Parasite Load ; Parasitemia/parasitology ; Plasmodium/physiology ; Plasmodium falciparum/immunology
    Language English
    Publishing date 2017-09-04
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-017-10480-1
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