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Träfflista för sökning "AMNE:(MEDICIN OCH HÄLSOVETENSKAP Medicinsk bioteknologi) ;pers:(Lammi Mikko 1961)"

Sökning: AMNE:(MEDICIN OCH HÄLSOVETENSKAP Medicinsk bioteknologi) > Lammi Mikko 1961

  • Resultat 1-10 av 49
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1.
  • Wang, Xi, et al. (författare)
  • Comparison of the major cell populations among osteoarthritis, Kashin-Beck disease and healthy chondrocytes by single-cell RNA-seq analysis
  • 2021
  • Ingår i: Cell Death and Disease. - : Springer Nature. - 2041-4889 .- 2041-4889. ; 12:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Chondrocytes are the key target cells of the cartilage degeneration that occurs in Kashin-Beck disease (KBD) and osteoarthritis (OA). However, the heterogeneity of articular cartilage cell types present in KBD and OA patients and healthy controls is still unknown, which has prevented the study of the pathophysiology of the mechanisms underlying the roles of different populations of chondrocytes in the processes leading to KBD and OA. Here, we aimed to identify the transcriptional programmes and all major cell populations in patients with KBD, patients with OA and healthy controls to identify the markers that discriminate among chondrocytes in these three groups. Single-cell RNA sequencing was performed to identify chondrocyte populations and their gene signatures in KBD, OA and healthy cells to investigate their differences as related to the pathogenetic mechanisms of these two osteochondral diseases. We performed immunohistochemistry and quantitative reverse-transcription PCR (qRT-PCR) assays to validate the markers for chondrocyte population. Ten clusters were labelled by cell type according to the expression of previously described markers, and one novel population was identified according to the expression of a new set of markers. The homeostatic and mitochondrial chondrocyte populations, which were identified by the expression of the unknown markers MT1X and MT2A and MT-ND1 and MT-ATP6, were markedly expanded in KBD. The regulatory chondrocyte population, identified by the expression of CHI3L1, was markedly expanded in OA. Our study allows us to better understand the heterogeneity of chondrocytes in KBD and OA and provides new evidence of differences in the pathogenetic mechanisms between these two diseases.
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2.
  • Fan, Yue, et al. (författare)
  • Unveiling inflammatory and prehypertrophic cell populations as key contributors to knee cartilage degeneration in osteoarthritis using multi-omics data integration
  • 2024
  • Ingår i: Annals of the Rheumatic Diseases. - : BMJ Publishing Group Ltd. - 0003-4967 .- 1468-2060.
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVES: Single-cell and spatial transcriptomics analysis of human knee articular cartilage tissue to present a comprehensive transcriptome landscape and osteoarthritis (OA)-critical cell populations.METHODS: Single-cell RNA sequencing and spatially resolved transcriptomic technology have been applied to characterise the cellular heterogeneity of human knee articular cartilage which were collected from 8 OA donors, and 3 non-OA control donors, and a total of 19 samples. The novel chondrocyte population and marker genes of interest were validated by immunohistochemistry staining, quantitative real-time PCR, etc. The OA-critical cell populations were validated through integrative analyses of publicly available bulk RNA sequencing data and large-scale genome-wide association studies.RESULTS: We identified 33 cell population-specific marker genes that define 11 chondrocyte populations, including 9 known populations and 2 new populations, that is, pre-inflammatory chondrocyte population (preInfC) and inflammatory chondrocyte population (InfC). The novel findings that make this an important addition to the literature include: (1) the novel InfC activates the mediator MIF-CD74; (2) the prehypertrophic chondrocyte (preHTC) and hypertrophic chondrocyte (HTC) are potentially OA-critical cell populations; (3) most OA-associated differentially expressed genes reside in the articular surface and superficial zone; (4) the prefibrocartilage chondrocyte (preFC) population is a major contributor to the stratification of patients with OA, resulting in both an inflammatory-related subtype and a non-inflammatory-related subtype.CONCLUSIONS: Our results highlight InfC, preHTC, preFC and HTC as potential cell populations to target for therapy. Also, we conclude that profiling of those cell populations in patients might be used to stratify patient populations for defining cohorts for clinical trials and precision medicine.
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3.
  • Lammi, Mikko J., 1961-, et al. (författare)
  • Regulation of oxygen tension as a strategy to control chondrocytic phenotype for cartilage tissue engineering and regeneration
  • 2024
  • Ingår i: Bioengineering. - : MDPI. - 2306-5354. ; 11:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Cartilage defects and osteoarthritis are health problems which are major burdens on health care systems globally, especially in aging populations. Cartilage is a vulnerable tissue, which generally faces a progressive degenerative process when injured. This makes it the 11th most common cause of global disability. Conservative methods are used to treat the initial phases of the illness, while orthopedic management is the method used for more progressed phases. These include, for instance, arthroscopic shaving, microfracturing and mosaicplasty, and joint replacement as the final treatment. Cell-based implantation methods have also been developed. Despite reports of successful treatments, they often suffer from the non-optimal nature of chondrocyte phenotype in the repair tissue. Thus, improved strategies to control the phenotype of the regenerating cells are needed. Avascular tissue cartilage relies on diffusion for nutrients acquisition and the removal of metabolic waste products. A low oxygen content is also present in cartilage, and the chondrocytes are, in fact, well adapted to it. Therefore, this raises an idea that the regulation of oxygen tension could be a strategy to control the chondrocyte phenotype expression, important in cartilage tissue for regenerative purposes. This narrative review discusses the aspects related to oxygen tension in the metabolism and regulation of articular and growth plate chondrocytes and progenitor cell phenotypes, and the role of some microenvironmental factors as regulators of chondrocytes.
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4.
  • Pulkkinen, Hertta, et al. (författare)
  • Recombinant human type II collagen as a material for cartilage tissue engineering.
  • 2008
  • Ingår i: International Journal of Artificial Organs. - : Wichtig Editore Srl. - 0391-3988 .- 1724-6040. ; 31:11, s. 960-969
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: Collagen type II is the major component of cartilage and would be an optimal scaffold material for reconstruction of injured cartilage tissue. In this study, the feasibility of recombinant human type II collagen gel as a 3-dimensional culture system for bovine chondrocytes was evaluated in vitro.METHODS: Bovine chondrocytes (4x106 cells) were seeded within collagen gels and cultivated for up to 4 weeks. The gels were investigated with confocal microscopy, histology, and biochemical assays.RESULTS: Confocal microscopy revealed that the cells maintained their viability during the entire cultivation period. The chondrocytes were evenly distributed inside the gels, and the number of cells and the amount of the extracellular matrix increased during cultivation. The chondrocytes maintained their round phenotype during the 4-week cultivation period. The glycosaminoglycan levels of the tissue increased during the experiment. The relative levels of aggrecan and type II collagen mRNA measured with realtime polymerase chain reaction (PCR) showed an increase at 1 week.CONCLUSION: Our results imply that recombinant human type II collagen is a promising biomaterial for cartilage tissue engineering, allowing homogeneous distribution in the gel and biosynthesis of extracellular matrix components.
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5.
  • Liu, Huan, et al. (författare)
  • The first human induced pluripotent stem cell line of Kashin–Beck disease reveals involvement of heparan sulfate proteoglycan biosynthesis and PPAR pathway
  • 2022
  • Ingår i: The FEBS Journal. - : John Wiley & Sons. - 1742-464X .- 1742-4658. ; 289:1, s. 279-293
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: Kashin-Beck disease (KBD) is an endemic osteochondropathy. Due to a lack of suitable animal or cellular disease models, the research progress on KBD has been limited. Our goal was to establish the first disease-specific human induced pluripotent stem cells (hiPSCs) cellular disease model of KBD, and to explore its etiology and pathogenesis exploiting transcriptome sequencing.METHODS: HiPSCs were reprogrammed from dermal fibroblasts of two KBD and one healthy control donors via integration-free vectors. Subsequently, hiPSCs were differentiated into chondrocytes through three-week culture. Gene expression profiles in KBD, normal primary chondrocytes and hiPSC-derived chondrocytes were defined by RNA sequencing. A Venn diagram was constructed to show the number of shared differentially expressed genes (DEGs) between KBD and normal. Gene oncology and Kyoto Encyclopedia of Genes and Genomes annotations were performed, and six DEGs were further validated in other individuals by real-time quantitative reverse transcription PCR (RT-qPCR).RESULTS: KBD cellular disease models were successfully established by generation of hiPSC lines. Seventeen consistent and significant DEGs present in all compared groups (KBD and normal) were identified. RT-qPCR validation gave consistent results with the sequencing data. Glycosaminoglycan biosynthesis-heparan sulfate/heparin, PPAR signaling pathway and cell adhesion molecules (CAMs) pathways were identified to be significantly altered in KBD.CONCLUSION: Differentiated chondrocytes deriving from KBD-origin hiPSCs provide the first cellular disease model for etiological studies of KBD. This study also provides new sights into the pathogenesis and etiology of KBD and is likely to inform the development of targeted therapeutics for its treatment.
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6.
  • Virén, Tuomas, et al. (författare)
  • Quantitative evaluation of spontaneously and surgically repaired rabbit articular cartilage using intra-articular ultrasound method in situ.
  • 2010
  • Ingår i: Ultrasound in Medicine and Biology. - : Elsevier. - 1879-291X .- 0301-5629. ; 36:5, s. 833-839
  • Tidskriftsartikel (refereegranskat)abstract
    • During the last decade, a major effort has been devoted to developing surgical methods for repairing localized articular cartilage lesions. Despite some promising results no ultimate breakthrough in surgical cartilage repair has been achieved. Improvements in repair techniques would benefit from more sensitive and quantitative methods for long-term follow-up of cartilage healing. In this study, the potential of a new ultrasound technique for detecting the compositional and structural changes in articular cartilage after surgery, using recombinant human type II collagen gel and spontaneous repair was, investigated. Rabbit knee joints containing intact (n = 13) and surgically (n = 8) or spontaneously (n = 5) repaired tissue were imaged in situ at 6 months after the operation using a clinical intravascular high-frequency (40 MHz) ultrasound device. Based on the ultrasound raw data, ultrasound reflection coefficient (R), integrated ultrasound reflection coefficient (IRC), apparent integrated backscattering coefficient (AIB) and ultrasound roughness index (URI) were determined for each sample. URI was significantly higher in both repair groups than in intact cartilage (p < 0.05). The reflection parameters (R and IRC) were significantly lower in surgically repaired cartilage (p < 0.05) than in intact cartilage. Furthermore, AIB was significantly higher in surgically repaired cartilage than in intact tissue (p < 0.05). To conclude, the integrity of the rabbit articular cartilage repair could be quantitatively evaluated with the nondestructive ultrasound approach. In addition, clinically valuable qualitative information on the changes in cartilage integration, structure and composition could be extracted from the ultrasound images. In the present study, the structure and properties of repaired tissue were inferior to native tissue at 6 months after the operation. The applied ultrasound device and probes are FDA approved and, thus, applicable for the quantitative in vivo evaluation of human articular cartilage.
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7.
  • Zhang, Yanan, et al. (författare)
  • Dysregulation of Cells Cycle and Apoptosis in Human Induced Pluripotent Stem Cells Chondrocytes Through p53 Pathway by HT-2 Toxin : An in vitro Study
  • 2021
  • Ingår i: Frontiers in Genetics. - : Frontiers Media S.A.. - 1664-8021. ; 12
  • Tidskriftsartikel (refereegranskat)abstract
    • Kashin–Beck disease (KBD) mainly damages growth plate of adolescents and is susceptible to both gene and gene–environmental risk factors. HT-2 toxin, which is a primary metabolite of T-2 toxin, was regarded as one of the environmental risk factors of KBD. We used successfully generated KBD human induced pluripotent stem cells (hiPSCs) and control hiPSCs, which carry different genetic information. They have potential significance in exploring the effects of HT-2 toxin on hiPSC chondrocytes and interactive genes with HT-2 toxin for the purpose of providing a cellular disease model for KBD. In this study, we gave HT-2 toxin treatment to differentiating hiPSC chondrocytes in order to investigate the different responses of KBD hiPSC chondrocytes and control hiPSC chondrocytes to HT-2 toxin. The morphology of HT-2 toxin-treated hiPSC chondrocytes investigated by transmission electron microscope clearly showed that the ultrastructure of organelles was damaged and type II collagen expression in hiPSC chondrocytes was downregulated by HT-2 treatment. Moreover, dysregulation of cell cycle was observed; and p53, p21, and CKD6 gene expressions were dysregulated in hiPSC chondrocytes after T-2 toxin treatment. Flow cytometry also demonstrated that there were significantly increased amounts of late apoptotic cells in KBD hiPSC chondrocytes and that the mRNA expression level of Fas was upregulated. In addition, KBD hiPSC chondrocytes presented stronger responses to HT-2 toxin than control hiPSC chondrocytes. These findings confirmed that HT-2 is an environmental risk factor of KBD and that p53 pathway interacted with HT-2 toxin, causing damaged ultrastructure of organelles, accelerating cell cycle in G1 phase, and increasing late apoptosis in KBD hiPSC chondrocytes.
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8.
  • Prittinen, Juha, 1989-, et al. (författare)
  • Effect of centrifugal force on the development of articular neocartilage with bovine primary chondrocytes
  • 2019
  • Ingår i: Cell and Tissue Research. - New York : Springer. - 0302-766X .- 1432-0878. ; 375:3, s. 629-639
  • Tidskriftsartikel (refereegranskat)abstract
    • A lot has been invested into understanding how to assemble cartilage tissue in vitro and various designs have been developed to manufacture cartilage tissue with native-like biological properties. So far, no satisfactory design has been presented. Bovine primary chondrocytes are used to self-assemble scaffold-free constructs to investigate whether mechanical loading by centrifugal force would be useful in manufacturing cartilage tissue in vitro. Six million chondrocytes were laid on top of defatted bone disks placed inside an agarose well in 50-ml culture tubes. The constructs were centrifuged once or three times per day for 15 min at a centrifugal force of 771×g for up to 4 weeks. Control samples were cultured under the same conditions without exposure to centrifugation. The samples were analysed by (immuno)histochemistry, Fourier transform infrared imaging, micro-computed tomography, biochemical and gene expression analyses. Biomechanical testing was also performed. The centrifuged tissues had a more even surface covering a larger area of the bone disk. Fourier transform infrared imaging analysis indicated a higher concentration of collagen in the top and bottom edges in some of the centrifuged samples. Glycosaminoglycan contents increased along the culture, while collagen content remained at a rather constant level. Aggrecan and procollagen α1(II) gene expression levels had no significant differences, while procollagen α2(I) levels were increased significantly. Biomechanical analyses did not reveal remarkable changes. The centrifugation regimes lead to more uniform tissue constructs, whereas improved biological properties of the native tissue could not be obtained by centrifugation.
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9.
  • Wang, Ying, et al. (författare)
  • Preliminary exploration of hsa_circ_0032131 levels in peripheral blood as a potential diagnostic biomarker of osteoarthritis
  • 2019
  • Ingår i: Genetic Testing and Molecular Biomarkers. - : Mary Ann Liebert. - 1945-0265 .- 1945-0257. ; 23:10, s. 717-721
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Osteoarthritis (OA) is a common chronic degenerative joint disease characterized by articular cartilage degeneration and synovitis. CircRNAs are increasingly being recognized as functional endogenous RNAs with a stable structure and high tissue specificity. Recent studies have shown that some circRNAs may be involved in the initiation and progression of OA and that there is differential expression of circRNAs in chondrocytes in vitro isolated from patients with OA.Purposes: In this study, we aimed to determine if circRNA levels in the peripheral blood of Chinese Han patients with OA would be diagnostic based on the previous in vitro studies.Methods: We collected peripheral blood samples from 25 patients suffering from OA and 25 healthy controls and measured hsa_circ_0032131_CBC1 RNA levels through quantitative RT-PCR (qRT-PCR). The statistical basis for evaluating the diagnostic value was to calculate the area under the receiver operator characteristic (ROC) curve.Results: The results of the qRT-PCR for hsa_circ_0032131_CBC1 were consistent with those of the microarray analysis. The ROC curve shows that hsa_circ_0032131 holds diagnostic value for OA (0.8455, p < 0.01).Conclusions: Our research indicates that differentially expressed circRNAs may be involved in the development of OA and could be used diagnostically.
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10.
  • Wang, Ying, et al. (författare)
  • Screening for Differentially Expressed Circular RNAs in the Cartilage of Osteoarthritis Patients for Their Diagnostic Value
  • 2019
  • Ingår i: Genetic Testing and Molecular Biomarkers. - : Mary Ann Liebert. - 1945-0265 .- 1945-0257. ; 23:10, s. 706-716
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Osteoarthritis (OA) is the most prevalent osteoarticular disease, which typically involves chronic cartilage degeneration and synovitis. The latest research shows that circular RNAs (circRNAs) play a role in the development of a variety of diseases, including osteoarthrosis.Purposes: The aim of this study was to explore the expression of circRNAs in OA chondrocytes and predict biomarkers for diagnosis.Materials and Methods: The circRNA expression profile was analyzed through use of the Gene Spring software V13.0; differentially expressed circRNAs were screened by comparing OA chondrocytes and normal articular chondrocytes. We validated the microarray data by quantitative real-time polymerase chain reaction analyses of OA chondrocytes and chondrocytes from normal controls. TargetScan software and miRanda software were used to predict networks of circRNA–miRNA interactions in cartilage. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analyses were applied to predict the functions of differentially expressed circRNAs.Results: Overall, 1380 circRNAs were differentially expressed between OA chondrocytes and normal articular chondrocytes (fold-change ≥2, p ≤ 0.05), including 215 that were upregulated and 1165 that were downregulated circRNAs. After analyzing the differentially expressed circRNA genes, the top 20 enriched GO entries and KEGG pathways were annotated. The hsa_circrna_0032131 was identified for further analysis. A circRNA–miRNA network was constructed to represent the 10 most likely target genes associated with the validated circRNA.Conclusions: Our research suggests that some of the differentially expressed circRNAs in OA chondrocytes compared to normal chondrocytes are etiologically associated with the pathological process of OA. It was found that hsa_circRNA_0032131 likely participates in the initiation and progression of OA and has potential as a diagnostic marker.Clinical Relevance: To analyze the difference of circRNA expression profiles between OA and normal controls and explore biomarkers for diagnosis.
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