World journal of stem cells最新文献

{"title":"Melatonin-based priming of stem cells to alleviate oxidative stress.","authors":"Khawaja Husnain Haider","doi":"10.4252/wjsc.v16.i11.985","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.985","url":null,"abstract":"<p><p>Stem cell expansion <i>in vitro</i> and transplantation in the cytokine-rich proinflammatory milieu in the injured tissue generate immense oxidative stress that interferes with the cells' survival, stemness, and repairability. Stem cell priming has gained popularity to overcome these issues. Given melatonin's oxidative-scavenging properties, Gu <i>et al</i> have used periodontal ligament stem cells cultured under oxidative stress as an <i>in vitro</i> model to study the cytoprotective effects of melatonin. Our letter to the editor delves into melatonin-induced stem cell priming and the underlying molecular mechanism, focusing on the intriguing role of Yes-associated protein signaling in alleviating oxidative stress. We stress the importance of understanding the distinction between <i>in vitro</i> and <i>in vivo</i> oxidative stress conditions, a crucial aspect of stem cell research that invokes a sense of critical thinking in the readership. The study by Gu <i>et al</i> presents a novel approach to oxidative stress management, offering exciting possibilities for future research and applications.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"985-989"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606350/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of miR-214-5p and miR-21-5p in hypoxic endometrial epithelial-cell-derived exosomes on human umbilical cord mesenchymal stem cells.","authors":"Wan-Yu Zhang, Han-Bi Wang, Cheng-Yan Deng","doi":"10.4252/wjsc.v16.i11.906","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.906","url":null,"abstract":"<p><strong>Background: </strong>Thin endometrium seriously affects endometrial receptivity, resulting in a significant reduction in embryo implantation, and clinical pregnancy and live birth rates, and there is no gold standard for treatment. The main pathophysiological characteristics of thin endometrium are increased uterine arterial blood flow resistance, angiodysplasia, slow growth of the glandular epithelium, and low expression of vascular endothelial growth factor, resulting in endometrial epithelial cell (EEC) hypoxia and endometrial tissue aplasia. Human umbilical cord mesenchymal stem cells (HucMSCs) promote repair and regeneration of damaged endometrium by secreting microRNA (miRNA)-carrying exosomes. However, the initiation mechanism of HucMSCs to repair thin endometrium has not yet been clarified.</p><p><strong>Aim: </strong>To determine the role of hypoxic-EEC-derived exosomes in function of HucMSCs and explore the potential mechanism.</p><p><strong>Methods: </strong>Exosomes were isolated from normal EECs (EEC-exs) and hypoxia-damaged EECs (EECD-exs), before characterization using Western blotting, nanoparticle-tracking analysis, and transmission electron microscopy. HucMSCs were cocultured with EEC-exs or EECD-exs and differentially expressed miRNAs were determined using sequencing. MiR-21-5p or miR-214-5p inhibitors or miR-21-3p or miR-214-5p mimics were transfected into HucMSCs and treated with a signal transducer and activator of transcription 3 (STAT3) activator or STAT3 inhibitor. HucMSC migration was assessed by Transwell and wound healing assays. Differentiation of HucMSCs into EECs was assessed by detecting markers of stromal lineage (Vimentin and CD13) and epithelial cell lineage (CK19 and CD9) using Western blotting and immunofluorescence. The binding of the miRNAs to potential targets was validated by dual-luciferase reporter assay.</p><p><strong>Results: </strong>MiR-21-5p and miR-214-5p were lowly expressed in EECD-ex-pretreated HucMSCs. MiR-214-5p and miR-21-5p inhibitors facilitated the migratory and differentiative potentials of HucMSCs. MiR-21-5p and miR-214-5p targeted STAT3 and protein inhibitor of activated STAT3, respectively, and negatively regulated phospho-STAT3. MiR-21-5p- and miR-214-5p-inhibitor-induced promotive effects on HucMSC function were reversed by STAT3 inhibition. MiR-21-5p and miR-214-5p overexpression repressed HucMSC migration and differentiation, while STAT3 activation reversed these effects.</p><p><strong>Conclusion: </strong>Low expression of miR-21-5p/miR-214-5p in hypoxic-EEC-derived exosomes promotes migration and differentiation of HucMSCs into EECs <i>via</i> STAT3 signaling. Exosomal miR-214-5p/miR-21-5p may function as valuable targets for thin endometrium.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"906-925"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606348/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exosome-based strategy against colon cancer using small interfering RNA-loaded vesicles targeting soluble a proliferation-inducing ligand.","authors":"Hyung-Jin Kim, Do Sang Lee, Jung Hyun Park, Ha-Eun Hong, Ho Joong Choi, Ok-Hee Kim, Say-June Kim","doi":"10.4252/wjsc.v16.i11.956","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.956","url":null,"abstract":"<p><strong>Background: </strong>Recent advancements in nanomedicine have highlighted the potential of exosome (Ex)-based therapies, utilizing naturally derived nanoparticles, as a novel approach to targeted cancer treatment.</p><p><strong>Aim: </strong>To explore the targetability and anticancer effectiveness of small interfering peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 RNA (siPIN1)-loaded soluble a proliferation-inducing ligand (sAPRIL)-targeted Exs (designated as tEx[p]) in the treatment of colon cancer models.</p><p><strong>Methods: </strong>tEx was generated by harvesting conditioned media from adipose-derived stem cells that had undergone transformation using pDisplay vectors encoding sAPRIL-binding peptide sequences. Subsequently, tEx[p] were created by incorporating PIN1 siRNA into the tEx using the Exofect kit. The therapeutic efficacy of these Exs was evaluated using both <i>in vitro</i> and <i>in vivo</i> models of colon cancer.</p><p><strong>Results: </strong>The tEx[p] group exhibited superior anticancer effects in comparison to other groups, including tEx, Ex[p], and Ex, demonstrated by the smallest tumor size, the slowest tumor growth rate, and the lightest weight of the excised tumors observed in the tEx[p] group (<i>P</i> < 0.05). Moreover, analyses of the excised tumor tissues, using western blot analysis and immunohistochemical staining, revealed that tEx[p] treatment resulted in the highest increase in E-cadherin expression and the most significant reduction in the mesenchymal markers Vimentin and Snail (<i>P</i> < 0.05), suggesting a more effective inhibition of epithelial-mesenchymal transition tEx[p], likely due to the enhanced delivery of siPIN1.</p><p><strong>Conclusion: </strong>The use of bioengineered Exs targeting sAPRIL and containing siPIN1 demonstrated superior efficacy in inhibiting tumor growth and epithelial-mesenchymal transition, highlighting their potential as a therapeutic strategy for colon cancer.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"956-973"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606353/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Yes-associated protein-mediated melatonin regulates the function of periodontal ligament stem cells under oxidative stress conditions.","authors":"Ke Gu, Xiao-Mei Feng, Shao-Qing Sun, Xing-Yao Hao, Yong Wen","doi":"10.4252/wjsc.v16.i11.926","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.926","url":null,"abstract":"<p><strong>Background: </strong>Human periodontal ligament stem cells (PDLSCs) regenerate oral tissue. <i>In vitro</i> expansion causes replicative senescence in stem cells. This causes intracellular reactive oxygen species (ROS) accumulation, which can impair stem cell function. Tissue engineering efficiency is reduced by exogenous ROS stimulation, which causes premature senescence under oxidative stress. Melatonin (MT), a powerful free radical scavenger, can delay PDLSCs senescence but may not maintain stemness under oxidative stress. This experiment examined the effects of hydrogen peroxide-induced oxidative stress on PDLSCs' apoptosis, senescence, and stemness.</p><p><strong>Aim: </strong>To determine if MT can reverse the above effects along with the underlying molecular mechanisms involved.</p><p><strong>Methods: </strong>PDLSCs were isolated from human premolars and cultured in different conditions. Flow cytometry was used to characterize the cell surface markers of PDLSCs. Hydrogen peroxide was used to induce oxidative stress in PDLSCs. Cell cycle, proliferation, apoptosis, differentiation, ROS, and senescence-associated β-galactosidase activity were assessed by various assays. Reverse transcription-polymerase chain reaction and western blot were used to measure the expression of genes and proteins related to stemness and senescence.</p><p><strong>Results: </strong>MT increases Yes-associated protein expression and maintains cell stemness in an induced inflammatory microenvironment, which may explain its therapeutic effects. We examined how MT affects PDLSCs aging and stemness and its biological mechanisms.</p><p><strong>Conclusion: </strong>Our study reveals MT's role in regulating oxidative stress in PDLSCs and Yes-associated protein-mediated activity, providing insights into cellular functions and new therapeutic targets for tissue regeneration.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"926-943"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606347/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of serum-free cultured human umbilical cord mesenchymal stem cells in the treatment of knee osteoarthritis in mice.","authors":"Kai-Zhen Xiao, Gui Liao, Guang-Yu Huang, Yun-Long Huang, Rong-He Gu","doi":"10.4252/wjsc.v16.i11.944","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.944","url":null,"abstract":"<p><strong>Background: </strong>We investigated the efficacy of intra-articular injection of human umbilical cord mesenchymal stem cells (hUC-MSCs) for the treatment of osteoarthritis (OA) progression in the knee joint. Although many experimental studies of hUC-MSCs have been published, these studies have mainly used fetal bovine serum-containing cultures of hUC-MSCs; serum-free cultures generally avoid the shortcomings of serum-containing cultures and are not subject to ethical limitations, have a wide range of prospects for clinical application, and provide a basis or animal experimentation for clinical experiments.</p><p><strong>Aim: </strong>To study the therapeutic effects of serum-free hUC-MSCs (N-hUCMSCs) in a mouse model of knee OA.</p><p><strong>Methods: </strong>Fifty-five male C57BL/6 mice were randomly divided into six groups: The blank control group, model control group, serum-containing hUC-MSCs (S-hUCMSC) group, N-hUCMSC group and hyaluronic acid (HA) group. After 9 weeks of modeling, the serum levels of interleukin (IL)-1β and IL-1 were determined. Hematoxylin-eosin staining was used to observe the cartilage tissue, and the Mankin score was determined. Immunohistochemistry and western blotting were used to determine the expression of collagen type II, matrix metalloproteinase (MMP)-1 and MMP-13.</p><p><strong>Results: </strong>The Mankin score and serum IL-1 and IL-1β and cartilage tissue MMP-1 and MMP-13 expression were significantly greater in the experimental group than in the blank control group (<i>P</i> < 0.05). Collagen II expression in the experimental group was significantly lower than that in the blank control group (<i>P</i> < 0.05). The Mankin score and serum IL-1 and IL-1β and cartilage tissue MMP-1 and MMP-13 levels the experimental group were lower than those in the model control group (<i>P</i> < 0.05). Collagen II expression in the experimental group was significantly greater than that in the model control group (<i>P</i> < 0.05).</p><p><strong>Conclusion: </strong>N-hUCMSC treatment significantly alleviate the pathological damage caused by OA. The treatment effects of the S- hUCMSC group and HA group were similar.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"944-955"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606352/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Refining adipose-derived stem cell isolation for optimal regenerative therapy.","authors":"Chun-Han Cheng, Wen-Rui Hao, Tzu-Hurng Cheng","doi":"10.4252/wjsc.v16.i11.978","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.978","url":null,"abstract":"<p><p>This article highlights the importance of optimizing the techniques used for isolating stromal vascular fraction cells from adipose tissue. Furthermore, by presenting key findings from the literature, it clarifies the effects of refined techniques on regenerative medicine and advocates for ongoing research and innovation to enhance therapeutic outcomes.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"978-984"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606351/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resilience and challenges: Evaluating the impact of stress conditions on mesenchymal stem cells across different passages.","authors":"Yue Ding, Fang Lin, Xiao-Ting Liang","doi":"10.4252/wjsc.v16.i11.974","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.974","url":null,"abstract":"<p><p>This article discussed a study by Almahasneh <i>et al</i>, which investigated how high glucose and severe hypoxia affected mesenchymal stem cells (MSCs) at different passages. This research provides insights into the resilience of higher-passage MSCs under stress conditions, challenging the common use of lower passage MSCs in clinical settings. While this study offers valuable perspectives on the adaptability of MSCs, it relies mainly on <i>in vitro</i> results from a single cell line, limiting broader applicability. It highlights the need for more comprehensive <i>in vivo</i> studies to validate these findings and better understand MSC behavior in clinical scenarios.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"974-977"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606354/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential of ginsenoside Rg1 to treat aplastic anemia <i>via</i> mitogen activated protein kinase pathway in cyclophosphamide-induced myelosuppression mouse model.","authors":"See-Hyoung Park","doi":"10.4252/wjsc.v16.i11.900","DOIUrl":"https://doi.org/10.4252/wjsc.v16.i11.900","url":null,"abstract":"<p><p>Aplastic anemia (AA) is a rare but serious condition in which the bone marrow fails to produce sufficient new blood cells, leading to fatigue, increased susceptibility to infection, and uncontrolled bleeding. In this editorial, we review and comment on an article by Wang <i>et al</i> published in 2024. This study aimed to evaluate the potential therapeutic benefits of ginsenoside Rg1 in AA, focusing on its protective effects and uncovering the underlying mechanisms. Cyclophosphamide (CTX) administration caused substantial damage to the structural integrity of the bone marrow and decreased the number of hematopoietic stem cells, thereby establishing an AA model. Compared with the AA group, ginsenoside Rg1 alleviated the effects of CTX by reducing apoptosis and inflammatory factors. Mechanistically, treatment with ginsenoside Rg1 significantly mitigated myelosuppression in mice by inhibiting the mitogen activated protein kinase signaling pathway. Thus, this study indicates that ginsenoside Rg1 could be effective in treating AA by reducing myelosuppression, primarily through its influence on the mitogen activated protein kinase signaling pathway. We expect that our review and comments will provide valuable insights for the scientific community related to this research and enhance the overall clarity of this article.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 11","pages":"900-905"},"PeriodicalIF":3.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11606349/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioengineering breakthroughs: The impact of stem cell models on advanced therapy medicinal product development.","authors":"José Mauro Granjeiro, Priscila Grion de Miranda Borchio, Icaro Paschoal Brito Ribeiro, Katiucia Batista Silva Paiva","doi":"10.4252/wjsc.v16.i10.860","DOIUrl":"10.4252/wjsc.v16.i10.860","url":null,"abstract":"<p><p>The burgeoning field of bioengineering has witnessed significant strides due to the advent of stem cell models, particularly in their application in advanced therapy medicinal products (ATMPs). In this review, we examine the multifaceted impact of these developments, emphasizing the potential of stem cell models to enhance the sophistication of ATMPs and to offer alternatives to animal testing. Stem cell-derived tissues are particularly promising because they can reshape the preclinical landscape by providing more physiologically relevant and ethically sound platforms for drug screening and disease modelling. We also discuss the critical challenges of reproducibility and accuracy in measurements to ensure the integrity and utility of stem cell models in research and application. Moreover, this review highlights the imperative of stem cell models to align with regulatory standards, ensuring using stem cells in ATMPs translates into safe and effective clinical therapies. With regulatory approval serving as a gateway to clinical adoption, the collaborative efforts between scientists and regulators are vital for the progression of stem cell applications from bench to bedside. We advocate for a balanced approach that nurtures innovation within the framework of rigorous validation and regulatory compliance, ensuring that stem cell-base solutions are maximized to promote public trust and patient health in ATMPs.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 10","pages":"860-872"},"PeriodicalIF":3.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11525646/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142569754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emergence of the stromal vascular fraction and secretome in regenerative medicine.","authors":"Ratan Kumar Choudhary, Shanti Choudhary, Abhishek Tripathi","doi":"10.4252/wjsc.v16.i10.896","DOIUrl":"10.4252/wjsc.v16.i10.896","url":null,"abstract":"<p><p>Recently, we read a mini-review published by Jeyaraman <i>et al</i>. The article explored the optimal methods for isolating mesenchymal stromal cells from adipose tissue-derived stromal vascular fraction (SVF). Key factors include tissue source, processing techniques, cell viability assessment, and the advantages/disadvantages of autologous <i>vs</i> allogeneic use. The authors emphasized the need for standardized protocols for SVF isolation, ethical and regulatory standards for cell-based therapy, and safety to advance mesenchymal stromal cell-based therapies in human patients. This manuscript shares our perspective on SVF isolation in canines. We discussed future directions to potentiate effective regenerative medicine therapeutics in human and veterinary medicine.</p>","PeriodicalId":23775,"journal":{"name":"World journal of stem cells","volume":"16 10","pages":"896-899"},"PeriodicalIF":3.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11525647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142569814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}