Molecular and biochemical parasitology最新文献

{"title":"Diversification of sphingolipid synthase activities in kinetoplastid protozoa","authors":"","doi":"10.1016/j.molbiopara.2024.111656","DOIUrl":"10.1016/j.molbiopara.2024.111656","url":null,"abstract":"<div><div>Phosphosphingolipids (PSL) are essential components of eukaryotic membranes. The major PSL in fungi and protists is inositol phosphorylceramide (IPC), while sphingomyelin (SM), and to a lesser extent ethanolamine phosphorylceramide (EPC) predominate in mammals. Most kinetoplastid protozoa have a syntenic locus that encodes a single sphingolipid synthase (<em>SLS</em>) gene. Uniquely, among the kinetoplastids, the salivarian (African) trypanosomes have expanded this locus from a single gene in <em>Trypanosoma vivax</em> (<em>TvSLS</em>) to four genes in <em>T. brucei</em> (<em>TbSLS1-4</em>). We have previously shown that one of these is an IPC synthase, while the others are SM/EPC synthases, and that specificity is controlled by a single signature residue (IPC, serine; SM/EPC, phenylalanine). This residue is serine in <em>T. cruz</em>i and <em>Leishmania major</em> SLSs, both of which are demonstrated IPC synthases. However, <em>T. vivax</em> has a tyrosine at this residue raising the issue of specificity. Using a liposome-supplemented <em>in vitro</em> translation system we now show that <em>T. vivax</em> SLS is an SM/EPC synthase, and that the basal kinetoplastid <em>Bodo saltans</em> SLS is an IPC synthase (serine). We use these data, and a multiple alignment of available sequences, to discuss the evolution of kinetoplastid SLSs and their unique expansion in <em>T. brucei</em> and related salivarian trypanosomes.</div></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142504311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of two phosphatase 2C domain-containing proteins PPM2A and PPM2B in Toxoplasma gondii.","authors":"Ao Zeng, Yongle Song, Xiaoting Wan, Bang Shen, Rui Fang, Junlong Zhao, Yanqin Zhou","doi":"10.1016/j.molbiopara.2024.111654","DOIUrl":"https://doi.org/10.1016/j.molbiopara.2024.111654","url":null,"abstract":"<p><p>Protein phosphatases Mg²⁺/Mn²⁺ dependent (PPMs), serine/threonine phosphatases, are widely distributed in apicomplexan parasites, and Toxoplasma gondii possesses the largest number of PPMs in the apicomplexan parasites. Though the function of some PPMs has been characterized in T. gondii, much less is known about two phosphatase 2C domain-containing proteins, PPM2A and PPM2B. PPM2A was identified as one of Toxoplasma Calmodulin's interacting proteins through proximity-based protein interaction BioID technology in the previous study, and PPM2B was the homolog of PPM2A in T. gondii. In this study, PPM2A was distributed in the whole tachyzoite of T. gondii, and PPM2B was mainly distributed in the cytoplasm by inserting a 10HA tag in the C-terminus of the two genes in the RH∆ku80 strain. PPM2A knockout (Δppm2a), PPM2B knockout (Δppm2b), and double knockout (ΔΔ) in RHΔhxgprt type I strain under CRISPR-Cas9 system did not result in intracellular replication defect. Besides, mouse experiments demonstrated that PPM2A, PPM2B, and double knockout did not reduce the pathogenicity of T. gondii compared with the RH∆hxgprt strain. However, the plaque size of these single knockout and double knockout strains were smaller than that in the control RH∆hxgprt strain. Our results provide new insight into the function of PPMs in the pathogenesis of T. gondii.</p>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142504310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biophysical analysis of the membrane-proximal Venus Flytrap domain of ESAG4 receptor-like adenylate cyclase from Trypanosoma brucei","authors":"","doi":"10.1016/j.molbiopara.2024.111653","DOIUrl":"10.1016/j.molbiopara.2024.111653","url":null,"abstract":"<div><div>The protozoan parasite <em>Trypanosoma brucei</em> possesses a large family of transmembrane receptor-like adenylate cyclases (RACs), primarily located to the flagellar surface and involved in sensing of the extracellular environment. RACs exhibit a conserved topology characterized by a large N-terminal extracellular moiety harbouring two Venus Flytrap (VFT) bilobate structures separated from an intracellular catalytic domain by a single transmembrane helix. RAC activation, which typically occurs under mild acid stress, requires the dimerization of the intracellular catalytic domain. The occurrence of VFT domains in the RAC’s extracellular moiety suggests their potential responsiveness to extracellular ligands in the absence of stress, although no such ligands have been identified so far. Herein we report the biophysical characterization of the membrane-proximal VFT2 domain of a bloodstream form-specific RAC called ESAG4, whose ectodomain 3D structure is completely unknown. The paper describes an AlphaFold2-based optimisation of the expression construct, enabling facile and high-yield recombinant production and purification of the target protein. Through an interdisciplinary approach combining various biophysical methods, we demonstrate that the optimised VFT2 domain obtained by recombination is properly folded and behaves as a monomer in solution. The latter suggests a ligand-binding capacity independent of dimerization, unlike typical mammalian VFT receptors, as guanylate cyclase. <em>In silico</em> VFT2 genomic analyses shows divergence among cyclase isoforms, hinting at ligand specificity. Taken together this improved procedure enabling facile and high-yield recombinant production and purification of the target protein could benefit researchers studying trypanosomal RAC VFT domains but also any trypanosome domain with poorly defined boundaries. Additionally, our findings support the stable monomeric VFT2 domain as a useful tool for future structural investigations and ligand screening.</div></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142504309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tissue and circulating levels of IL-17A and FoxP3+ in patients with scabies: Correlation with clinical features","authors":"","doi":"10.1016/j.molbiopara.2024.111652","DOIUrl":"10.1016/j.molbiopara.2024.111652","url":null,"abstract":"<div><p>The scabies mite is known to induce a complicated immune response that involves both innate and long-term adaptive immunity. Many immune effectors and pathways are involved. Th17/Treg balance can influence the complex immune response to scabies. The immunological effectors including IL-17A, as a pro-inflammatory cytokine, and Treg cells, anti-inflammatory regulatory T cells, are essential for preserving cutaneous immunological homeostasis. So, evaluating these immune effectors may help in comprehending the pathophysiology of scabies and facilitate the development of new treatment approaches. This study examined the expression of IL-17A and FoxP3⁺ in the skin and serum of 50 scabies patients and 25 healthy controls. An assessment of their correlation with clinical features was performed. Regarding tissue response, scabietic patients exhibited a significant increase in IL-17A and FoxP3⁺ expression in their epidermis and dermis compared to controls (P&lt;0.001), but the correlation between these factors was not significant in either area (P&gt;0.05). Also, patients showed a significant increase in serum IL-17A levels compared to controls (P&lt;0.001), with a significant association between serum IL-17A levels and lesion severity, but no significant correlation was observed between skin and serum responses (P&gt;0.05). In conclusion, there was increased expression of both IL-17A and FoxP3⁺, with FoxP3⁺ being significantly more abundant than IL^-17A in the skin of scabies patients. Skin FoxP3⁺ up-regulation has been linked to the severity of the condition.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142094862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using machine learning to dissect host kinases required for Leishmania internalization and development","authors":"","doi":"10.1016/j.molbiopara.2024.111651","DOIUrl":"10.1016/j.molbiopara.2024.111651","url":null,"abstract":"<div><p>The <em>Leishmania</em> life cycle alternates between promastigotes, found in the sandfly, and amastigotes, found in mammals. When an infected sandfly bites a host, promastigotes are engulfed by phagocytes (<em>i.e.</em>, neutrophils, dendritic cells, and macrophages) to establish infection. When these phagocytes die or break down, amastigotes must be re-internalized to survive within the acidic phagolysosome and establish disease. To define host kinase regulators of <em>Leishmania</em> promastigote and amastigote uptake and survival within macrophages, we performed an image-based kinase regression screen using a panel of 38 kinase inhibitors with unique yet overlapping kinase targets. We also targeted inert beads to complement receptor 3 (CR3) or Fcγ receptors (FcR) as controls by coating them with complement/C3bi or IgG respectively. Through this approach, we identified several putative host kinases that regulate receptor-mediated phagocytosis and/or the uptake of <em>L. amazonensis</em>. Findings included kinases previously implicated in <em>Leishmania</em> uptake (such as Src family kinases (SFK), Abl family kinases (ABL1/c-Abl, ABL2/Arg), and spleen tyrosine kinase (SYK)), but we also uncovered many novel kinases. Our methods also predicted host kinases necessary for promastigotes to convert to amastigotes or for amastigotes to survive within macrophages. Overall, our results suggest that the concerted action of multiple interconnected networks of host kinases are needed over the course of <em>Leishmania</em> infection<em>,</em> and that the kinases required for the parasite’s life cycle may differ substantially depending on which receptors are bound and the life cycle stage that is internalized. In addition, using our screen, we identified kinases that appear to preferentially regulate the uptake of parasites over beads, indicating that the methods required for <em>Leishmania</em> to be internalized by macrophages may differ from generalized phagocytic mechanisms. Our findings are intended to be used as a hypothesis generation resource for the broader scientific community studying the roles of kinases in host-pathogen interactions.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142056093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The genetically encoded calcium indicator GCaMP3 reveals spontaneous calcium oscillations at asexual stages of the human malaria parasite Plasmodium falciparum","authors":"","doi":"10.1016/j.molbiopara.2024.111650","DOIUrl":"10.1016/j.molbiopara.2024.111650","url":null,"abstract":"<div><p>Most protocols used to study the dynamics of calcium (Ca²⁺) in the malaria parasite are based on dyes, which are invasive and do not allow discrimination between the signal from the host cell and the parasite. To avoid this pitfall, we have generated a parasite line expressing the genetically encoded calcium sensor GCaMP3. The PfGCaMP3 parasite line is an innovative tool for studying spontaneous intracellular Ca²⁺ oscillations without external markers. Using this parasite line, we demonstrate the occurrence of spontaneous Ca²⁺ oscillations in the ring, trophozoite, and schizont stages in <em>Plasmodium falciparum</em>. Using the Fourier transform to fluorescence intensity data extracted from different experiments, we observe cytosolic Ca²⁺ fluctuations. These spontaneous cytosolic Ca²⁺ oscillations occur in the three intraerythrocytic stages of the parasite, with most oscillations occurring in the ring and trophozoite stages. A control parasite line expressing only a GFP control did not reveal such fluctuations, demonstrating the specificity of the observations. Our results clearly show dynamic, spontaneous Ca²⁺ oscillations during the asexual stage in <em>P. falciparum</em>, independent from external stimuli.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141996199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Target screening using RNA interference in the sheep abomasal nematode parasite Haemonchus contortus","authors":"","doi":"10.1016/j.molbiopara.2024.111648","DOIUrl":"10.1016/j.molbiopara.2024.111648","url":null,"abstract":"<div><p>RNA interference (RNAi) on parasitic nematodes has been described as a valuable tool for screening putative targets that could be used as novel drug and/or vaccine candidates. This study aimed to set up a pipeline to identify potential targets using RNAi for vaccine/anti-parasite therapy development against <em>Haemonchus contortus</em>, a blood-feeding abomasal nematode parasite. The available <em>H. contortus</em> sequence data was mined for targets, which were tested for essentiality using RNAi electroporation assays. A total of 56 genes were identified and tested for knockdown using electroporation of first-stage larvae (L1) <em>H. contortus</em> with the target double-stranded RNA. Electroporation of L1 proved to be effective overall; 17 targets had a strong phenotype and significant reduction in alive <em>H. contortus</em>, and another 24 had a moderate phenotype with a significant reduction in larvae development. A total of 28 targets showed a significant reduction in the development of <em>H. contortus</em> larvae to the infective stage (L3) following the RNAi assay. Down-regulation of target transcript levels was evaluated in some targets by semi-quantitative PCR. Four out of five genes tested showed complete knockdown of mRNA levels via semi-quantitative PCR, whereas the knockdown was partial for one. In conclusion, the results indicate that the RNAi pathway is confirmed in <em>H. contortus</em> and that several target genes have the potential to be investigated further as possible vaccine candidates.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141616856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neuroprotective effects of CysLT2R antagonist on Angiostrongylus cantonensis-induced edema and meningoencephalitis","authors":"","doi":"10.1016/j.molbiopara.2024.111649","DOIUrl":"10.1016/j.molbiopara.2024.111649","url":null,"abstract":"<div><p>Cysteinyl leukotrienes (CysLTs) can induce a disruption of the blood–brain barrier (BBB), and this reaction is mediated by cysteinyl-leukotriene receptors. In this study, we used <em>A. cantonensis</em>-induced eosinophilic meningoencephalitis as a model to investigate whether the CysLT2 receptor involved in the pathogenesis of angiostrongyliasis meningoencephalitis. The present study provides evidence that the CysLT2 receptor antagonist HAMI3379 reduced the number of infiltrated eosinophils and brain edema in eosinophilic meningoencephalitis. Additionally, we found that HAMI3379 significantly decreased the protein levels of M1 polarisation markers (CD80, iNOS, IL-5 and TNF-α), increased the expression of M2 polarisation markers (CD206, IL-10 and TGF-β) both <em>in vivo</em> and <em>in vitro</em>. Matrix metalloproteinase-9, S100B, GFAP, fibronectin, and claudin-5 were markedly lower after HAMI3379 treatment. Therefore, HAMI3379 reduced the BBB dysfunction in angiostrongyliasis meningoencephalitis. We have identified microRNA-155 as a BBB dysfunction marker in eosinophilic meningoencephalitis. The results showed that microRNA-155 was 15-fold upregulated in eosinophilic meningoencephalitis and 20-fold upregulated after HAMI3379 treatment. Our results suggest that CysLT2R may be involved in <em>A. cantonensis</em>-induced brain edema and eosinophilic meningoencephalitis and that down-regulation of CysLT2R could be a novel and potential therapeutic strategy for the treatment of angiostrongyliasis meningoencephalitis.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141616855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Avirulent UG10 Entamoeba histolytica mutant derived from HM-1:IMSS strain shows limited genome variability and aberrant 5-methyl cytosine genomic distribution","authors":"","doi":"10.1016/j.molbiopara.2024.111647","DOIUrl":"10.1016/j.molbiopara.2024.111647","url":null,"abstract":"<div><p><em>Entamoeba histolytica</em>, an intestinal parasite of global significance, poses substantial health risks with its associated high morbidity and mortality rates. Despite the current repertoire of molecular tools for the study of gene function in, the regulatory mechanisms governing its pathogenicity remain largely unexplored. This knowledge gap underscores the need to elucidate key genetic determinants orchestrating cellular functions critical to its virulence. Previously, our group generated an avirulent strain, termed UG10, with the same genetic background as the HM1:IMSS strain. UG10 strain, despite showing normal expression levels of well-known virulence factors, was unable to perform <em>in-vitro</em> and <em>in-vivo</em> activities related to amoebic virulence. In this study, we aimed to uncover the genome-wide modifications that rendered the avirulent phenotype of the UG10 strain through whole-genome sequencing. As a complementary approach, we conducted Methylated DNA Immunoprecipitation coupled with sequencing (MeDIP-seq) analysis on both the highly virulent HM1:IMSS strain and the low-virulence UG10 strain to uncover the genome-wide methylation profile. These dual methodologies revealed two aspects of the UG10 avirulent strain. One is the random integration of fragments from the ribosomal gene cluster and tRNA genes, ranging from 120 to 400 bp; and secondly, a clear, enriched methylation profile in the coding and non-coding strand relative to the start codon sequence in genes encoding small GTPases, which is associated with the previously described avirulent phenotype. This study provides the foundation to explore other genetic and epigenetic regulatory circuitries in <em>E. histolytica</em> and novel targets to understand the pathogenic mechanism of this parasite.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141603891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Therapeutic potential of hydantoin and thiohydantoin compounds against Schistosoma mansoni: An integrated in vitro, DNA, ultrastructural, and ADMET in silico approach","authors":"Antônio Sérgio de Almeida Júnior ,&nbsp;Mayse Manuele Freitas Viana Leal ,&nbsp;Diego Santa Clara Marques ,&nbsp;Anekécia Lauro da Silva ,&nbsp;Rafael de Souza Bezerra ,&nbsp;Yandra Flaviana Siqueira de Souza ,&nbsp;Maria Eduardade Mendonça Silveira ,&nbsp;Fábio AB Santos ,&nbsp;Luiz Carlos Alves ,&nbsp;André de Lima Aires ,&nbsp;Iranildo José da Cruz Filho ,&nbsp;Maria do Carmo Alves de Lima","doi":"10.1016/j.molbiopara.2024.111646","DOIUrl":"10.1016/j.molbiopara.2024.111646","url":null,"abstract":"<div><p>The study aimed to conduct <em>in vitro</em> biological assessments of hydantoin and thiohydantoin compounds against mature <em>Schistosoma mansoni</em> worms, evaluate their cytotoxic effects and predict their pharmacokinetic parameters using computational methods. The compounds showed low <em>in vitro</em> cytotoxicity and were not considered hemolytic. Antiparasitic activity against adult <em>S. mansoni</em> worms was tested with all compounds at concentrations ranging from 200 to 6.25 μM. Compounds SC01, SC02, and SC03 exhibited low activity. Compounds SC04, SC05, SC06 and SC07 caused 100 % mortality within 24 h of incubation at a concentration of 100 and 200 μM. Thiohydantoin SC04 exhibited the highest activity, resulting in 100 % mortality after 24 h of incubation at a concentration of 50 μM and IC₅₀ of 28 µM. In the ultrastructural analysis (SEM), the compound SC04 (200 µM) induced integumentary changes, formation of integumentary blisters, and destruction of tubercles and spicules. Therefore, the SC04 compound shows promise as an antiparasitic against <em>S. mansoni</em>.</p></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141476883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}