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1.
Geroscience ; 46(1): 1211-1228, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37523034

ABSTRACT

Frailty, a prevalent clinical syndrome in aging adults, is characterized by poor health outcomes, represented via a standardized frailty-phenotype (FP), and Frailty Index (FI). While the relevance of the syndrome is gaining awareness, much remains unclear about its underlying biology. Further elucidation of the genetic determinants and possible underlying mechanisms may help improve patients' outcomes allowing healthy aging.Genotype, clinical and demographic data of subjects (aged 60-73 years) from UK Biobank were utilized. FP was defined on Fried's criteria. FI was calculated using electronic-health-records. Genome-wide-association-studies (GWAS) were conducted and polygenic-risk-scores (PRS) were calculated for both FP and FI. Functional analysis provided interpretations of underlying biology. Finally, machine-learning (ML) models were trained using clinical, demographic and PRS towards identifying frail from non-frail individuals.Thirty-one loci were significantly associated with FI accounting for 12% heritability. Seventeen of those were known associations for body-mass-index, coronary diseases, cholesterol-levels, and longevity, while the rest were novel. Significant genes CDKN2B and APOE, previously implicated in aging, were reported to be enriched in lipoprotein-particle-remodeling. Linkage-disequilibrium-regression identified specific regulation in limbic-system, associated with long-term memory and cognitive-function. XGboost was established as the best performing ML model with area-under-curve as 85%, sensitivity and specificity as 0.75 and 0.8, respectively.This study provides novel insights into increased vulnerability and risk stratification of frailty syndrome via a multi-modal approach. The findings suggest frailty as a highly polygenic-trait, enriched in cholesterol-remodeling and metabolism and to be genetically associated with cognitive abilities. ML models utilizing FP and FI + PRS were established that identified frailty-syndrome patients with high accuracy.


Subject(s)
Frailty , Aged , Humans , Frailty/genetics , Frail Elderly , UK Biobank , Biological Specimen Banks , Genetic Risk Score , Biomarkers , Cholesterol
2.
J Chin Med Assoc ; 86(8): 748-755, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37220416

ABSTRACT

BACKGROUND: Liver transplantation (LT) is being increasingly performed for alcohol-related liver disease (ALD). It is unclear whether the increasing frequency of LTs in ALD patients has a negative impact on deceased-donor (DDLT) allocation and whether the current policy of 6 months of abstinence before transplantation effectively prevents recidivism after transplantation or improves long-term outcomes. METHODS: A total of 506 adult LT recipients, including 97 ALD patients, were enrolled. The outcomes of ALD patients were compared with those of non-ALD patients. The 97 ALD patients were further divided into group A (6-month abstinence) and group N (nonabstinence) based on the pretransplant alcohol withdrawal period. The incidence of relapsed drinking and the long-term outcomes were compared between the two groups. RESULTS: The prevalence of LT for ALD significantly increased after 2016 (27.0% vs 14.0%; p < 0.01), but the frequency of DDLT for ALD remained unchanged (22.6% vs 34.1%, p = 0.210). After a median follow-up of 56.9 months, patient survival was comparable between the ALD and non-ALD patients (1, 3, and 5 years posttransplant: 87.6%, 84.3%, and 79.5% vs 82.8%, 76.6%, and 72.2%, respectively; p = 0.396). The results were consistent irrespective of the transplant type and disease severity. In ALD patients, 22 of the 70 (31.4%) patients reported relapsed drinking after transplantation, and the prevalence in group A had a higher tendency than that in group N (38.3% vs 17.4%, p = 0.077). Six months of abstinence or nonabstinence did not result in a survival difference, and de novo malignancies were the leading cause of late patient death in ALD patients. CONCLUSION: LT achieves favorable outcomes for ALD patients. Six months of abstinence pretransplant did not predict the risk of recidivism after transplantation. The high incidence of de novo malignancies in these patients warrants a more comprehensive physical evaluation and better lifestyle modifications to improve long-term outcomes.


Subject(s)
Alcoholism , Liver Diseases, Alcoholic , Liver Transplantation , Substance Withdrawal Syndrome , Adult , Humans , Liver Diseases, Alcoholic/surgery , Liver Diseases, Alcoholic/epidemiology , Recurrence
3.
Front Cell Dev Biol ; 10: 948819, 2022.
Article in English | MEDLINE | ID: mdl-36147742

ABSTRACT

Sarcopenia is an age-related progressive loss of skeletal muscle mass, quality, and strength disease. In addition, sarcopenia is tightly correlated with age-associated pathologies, such as sarcopenic obesity and osteoporosis. Further understanding of disease mechanisms and the therapeutic strategies in muscle regeneration requires a deeper knowledge of the interaction of skeletal muscle and other cells in the muscle tissue. Skeletal muscle regeneration is a complex process that requires a series of highly coordinated events involving communication between muscle stem cells and niche cells, such as muscle fibro/adipogenic progenitors and macrophages. Macrophages play a critical role in tissue regeneration and the maintenance of muscle homeostasis by producing growth factors and cytokines that regulate muscle stem cells and myofibroblast activation. Furthermore, the aging-related immune dysregulation associated with the release of trophic factors and the polarization in macrophages transiently affect the inflammatory phase and impair muscle regeneration. In this review, we focus on the role and regulation of macrophages in skeletal muscle regeneration and homeostasis. The aim of this review is to highlight the important roles of macrophages as a therapeutic target in age-related sarcopenia and the increasing understanding of how macrophages are regulated will help to advance skeletal muscle regeneration.

4.
Analyst ; 147(7): 1425-1439, 2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35253812

ABSTRACT

Raman spectroscopy is a non-destructive analysis technique that provides detailed information about the chemical structure of tumors. Raman spectra of 52 giant cell tumors of bone (GCTB) and 21 adjacent normal tissues of formalin-fixed paraffin embedded (FFPE) and frozen specimens were obtained using a confocal Raman spectrometer and analyzed with machine learning and deep learning algorithms. We discovered characteristic Raman shifts in the GCTB specimens. They were assigned to phenylalanine and tyrosine. Based on the spectroscopic data, classification algorithms including support vector machine, k-nearest neighbors and long short-term memory (LSTM) were successfully applied to discriminate GCTB from adjacent normal tissues of both the FFPE and frozen specimens, with the accuracy ranging from 82.8% to 94.5%. Importantly, our LSTM algorithm showed the best performance in the discrimination of the frozen specimens, with a sensitivity and specificity of 93.9% and 95.1% respectively, and the AUC was 0.97. The results of our study suggest that confocal Raman spectroscopy accomplished by the LSTM network could non-destructively evaluate a tumor margin by its inherent biochemical specificity which may allow intraoperative assessment of the adequacy of tumor clearance.


Subject(s)
Deep Learning , Giant Cell Tumors , Algorithms , Humans , Spectrum Analysis, Raman/methods , Support Vector Machine
5.
JMIR Mhealth Uhealth ; 9(10): e32444, 2021 10 08.
Article in English | MEDLINE | ID: mdl-34538776

ABSTRACT

BACKGROUND: Margin reflex distance 1 (MRD1), margin reflex distance 2 (MRD2), and levator muscle function (LF) are crucial metrics for ptosis evaluation and management. However, manual measurements of MRD1, MRD2, and LF are time-consuming, subjective, and prone to human error. Smartphone-based artificial intelligence (AI) image processing is a potential solution to overcome these limitations. OBJECTIVE: We propose the first smartphone-based AI-assisted image processing algorithm for MRD1, MRD2, and LF measurements. METHODS: This observational study included 822 eyes of 411 volunteers aged over 18 years from August 1, 2020, to April 30, 2021. Six orbital photographs (bilateral primary gaze, up-gaze, and down-gaze) were taken using a smartphone (iPhone 11 Pro Max). The gold-standard measurements and normalized eye photographs were obtained from these orbital photographs and compiled using AI-assisted software to create MRD1, MRD2, and LF models. RESULTS: The Pearson correlation coefficients between the gold-standard measurements and the predicted values obtained with the MRD1 and MRD2 models were excellent (r=0.91 and 0.88, respectively) and that obtained with the LF model was good (r=0.73). The intraclass correlation coefficient demonstrated excellent agreement between the gold-standard measurements and the values predicted by the MRD1 and MRD2 models (0.90 and 0.84, respectively), and substantial agreement with the LF model (0.69). The mean absolute errors were 0.35 mm, 0.37 mm, and 1.06 mm for the MRD1, MRD2, and LF models, respectively. The 95% limits of agreement were -0.94 to 0.94 mm for the MRD1 model, -0.92 to 1.03 mm for the MRD2 model, and -0.63 to 2.53 mm for the LF model. CONCLUSIONS: We developed the first smartphone-based AI-assisted image processing algorithm for eyelid measurements. MRD1, MRD2, and LF measures can be taken in a quick, objective, and convenient manner. Furthermore, by using a smartphone, the examiner can check these measurements anywhere and at any time, which facilitates data collection.


Subject(s)
Blepharoptosis , Smartphone , Adult , Algorithms , Artificial Intelligence , Eyelids , Humans , Middle Aged
6.
Arthritis Res Ther ; 23(1): 110, 2021 04 10.
Article in English | MEDLINE | ID: mdl-33838669

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) has long been regarded as a disease of cartilage degeneration, whereas mounting evidence implies that low-grade inflammation contributes to OA. Among inflammatory cells involved, macrophages play a crucial role and are mediated by the local microenvironment to exhibit different phenotypes and polarization states. Therefore, we conducted a systematic review to uncover the phenotypic alterations of macrophages during OA and summarized the potential therapeutic interventions via modulating macrophages. METHODS: A systematic review of multiple databases (PubMed, Web of Science, ScienceDirect, Medline) was performed up to February 29, 2020. Included articles were discussed and evaluated by two independent reviewers. Relevant information was analyzed with a standardized and well-designed template. RESULTS: A total of 28 studies were included. Results were subcategorized into two sections depending on sources from human tissue/cell-based studies (12 studies) and animal experiments (16 studies). The overall observation indicated that M1 macrophages elevated in both synovium and circulation during OA development, along with lower numbers of M2 macrophages. The detailed alterations of macrophages in both synovium and circulation were listed and analyzed. Furthermore, interventions against OA via regulating macrophages in animal models were highlighted. CONCLUSION: This study emphasized the importance of the phenotypic alterations of macrophages in OA development. The classical phenotypic subcategory of M1 and M2 macrophages was questionable due to controversial and conflicting results. Therefore, further efforts are needed to categorize macrophages in an exhaustive manner and to use advanced technologies to identify the individual roles of each subtype of macrophages in OA.


Subject(s)
Osteoarthritis , Animals , Humans , Inflammation , Macrophages , Phenotype , Synovial Membrane
7.
PLoS One ; 16(2): e0247412, 2021.
Article in English | MEDLINE | ID: mdl-33630875

ABSTRACT

BACKGROUND/OBJECTIVE: High tibial osteotomy (HTO) is a common treatment for medial knee arthrosis. However, a high rate of complications associated with a plate and a significant loss of correction have been reported. Therefore, an internal support block (ISB) is designed to enhance the initial stability of the fixation device that is important for successful bone healing and maintenance of the correction angle of the osteotomy site. The purpose of this study was performed to examine if an internal support block combined with a plate reduces the stress on the plate and screw area. METHODS: Finite element models were reconstructed following three different implant combinations. Two loading conditions were applied to simulate standing and initial sit-to-stand postures. Data analysis was conducted to evaluate the axial displacement of the posteromedial tibial plateau, which represents the loss of the posteromedial tibial plateau in clinical observation. Moreover, the stresses on the bone plate and locking screws were evaluated. RESULTS: Compared to the TomoFix plate, the ISB reduced the axial displacement by 73% and 76% in standing and initial sit-to-stand loading conditions, respectively. The plate with an ISB reduced stress by 90% on the bone plate and by 73% on the locking screw during standing compared to the standalone TomoFix plate. During the initial sit-to-stand loading condition, the ISB reduced the stress by 93% and 77% on the bone plate and the locking screw, respectively. CONCLUSION: The addition of the PEEK block showed a benefit for structural stability in the osteotomy site. However, further clinical trials are necessary to evaluate the clinical benefit of reduced implant stress and the internal support block on the healing of the medial bone tissue.


Subject(s)
Biomechanical Phenomena/physiology , Osteotomy/instrumentation , Tibia/surgery , Bone Plates , Bone Screws , Finite Element Analysis , Humans , Osteoarthritis, Knee/surgery
9.
Stem Cells Transl Med ; 9(10): 1218-1232, 2020 10.
Article in English | MEDLINE | ID: mdl-32534464

ABSTRACT

Skin is the largest organ of the human body. Skin wound is one of the most common forms of wound. Mesenchymal stromal cells (MSCs) have been used to aid skin wound healing via their paracrine factors. Because the secretome of MSCs can be greatly enriched and amplified by treatment with IFN-γ and TNF-α (IT), we here tested whether supernatant derived from MSCs pretreated with IT, designated as S-MSCs-IT, possesses improved wound healing effect by using a murine model of cutaneous excision, S-MSCs-IT was found to be more potent in promoting angiogenesis, constricting collagen deposition and accelerating wound closure than control supernatant (S-MSCs) during the healing of skin wound. VEGFC, but not VEGFA, was greatly upregulated by IT and was found to be a key factor in mediating the improved wound healing effect of S-MSCs-IT. Our results indicate that the beneficial paracrine effect of MSCs on wound healing can be enhanced by pretreatment with inflammatory cytokines. IT treatment may represent a new strategy for optimizing the therapeutic effect of MSCs on skin injuries.


Subject(s)
Cytokines/metabolism , Mesenchymal Stem Cells/metabolism , Skin/pathology , Vascular Endothelial Growth Factor C/metabolism , Wound Healing/physiology , Animals , Female , Humans , Mice , Transfection
10.
Sci Adv ; 6(6): eaay0264, 2020 02.
Article in English | MEDLINE | ID: mdl-32076643

ABSTRACT

During endoderm formation, cell identity and tissue morphogenesis are tightly controlled by cell-intrinsic and cell-extrinsic factors such as biochemical and physical inputs. While the effects of biochemical factors are well studied, the physical cues that regulate cell division and differentiation are poorly understood. RNA sequencing analysis demonstrated increases of endoderm-specific gene expression in hPSCs cultured on soft substrate (Young's modulus, 3 ± 0.45 kPa) in comparison with hard substrate (Young's modulus, 165 ± 6.39 kPa). Further analyses revealed that multiple long noncoding RNAs (lncRNAs) were up-regulated on soft substrate; among them, LINC00458 was identified as a stiffness-dependent lncRNA specifically required for hPSC differentiation toward an early endodermal lineage. Gain- and loss-of-function experiments confirmed that LINC00458 is functionally required for hPSC endodermal lineage specification induced by soft substrates. Our study provides evidence that mechanical cues regulate the expression of LINC00458 and induce differentiation of hPSC into hepatic lineage progenitors.


Subject(s)
Endoderm/cytology , Endoderm/metabolism , Gene Expression Regulation, Developmental , RNA, Long Noncoding/genetics , Smad2 Protein/genetics , Smad3 Protein/genetics , Animals , Cell Differentiation/genetics , Cell Line , Cell Lineage/genetics , Cells, Cultured , Extracellular Matrix , Gene Expression Profiling , Gene Knockdown Techniques , Humans , Mice , Models, Biological , Organ Specificity/genetics , RNA Interference , Transcriptome
11.
J Orthop Translat ; 20: 31-36, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31908931

ABSTRACT

BACKGROUND: Alignment correction of the lower limb by medial open-wedge high tibial osteotomy (HTO) is an efficient technique, but loss of correction and hardware failure can occur owing to inadequate fixation. A surgical technique using opposite screw insertion was previously applied for salvage of the lateral hinge fracture, but evidence for its utility as a protective strategy was unclear. METHODS: Finite element models were reconstructed using artificial bone models, commercial bone plate, and locking screws in the HTO model. The 6.5-mm cancellous or 6.5/8.0-mm pretensioned lag screw was virtually inserted from the opposite cortex to the medial tibial plateau. Testing loads were applied for simulating standing and initial sit-to-stand postures. The axial displacement of the posteromedial tibial plateau, which represents the loss of the posteromedial tibial plateau in clinical observation, and stresses on the bone plate, locking screws, and opposite screws were evaluated. RESULTS: Pretensioned lag screw insertion effectively reduced the loss of posteromedial reduction compared with the HTO model without opposite screw insertion [6.5-mm lag screw, by 50.8% (standing)/56.3% (sit-to-stand); 8.0-mm lag screws, by 51.9% (standing)/57.5% (sit-to-stand); normalised by the performance in the intact model]. The noncompressed opposite cancellous screw slightly reduced the stresses on the bone plate and screws, but did not contribute to the control of reduction loss at the posteromedial tibial plateau. Stresses on screws were lower than those on the corresponding bone plates, so the risk of screw breakage may be low. CONCLUSION: The present study revealed that pretensioned opposite lag screw insertion is a simple and effective technique to improve the structural stability in medial open-wedge HTO. Further biomechanical and clinical verification will be required to enhance user confidence in this technique. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: The efficacy and advantages of additional opposite lag screw insertion in medial wedge high tibial osteotomy surgery have been described in this current study by a virtual biomechanical evaluation. Basing on this observation, it would worth further clinical trials for clarification and verification in reality.

12.
J Orthop Res ; 38(2): 297-310, 2020 02.
Article in English | MEDLINE | ID: mdl-31471919

ABSTRACT

Giant cell tumor of bone (GCTB) is a locally aggressive destructive bone lesion. The management of pulmonary metastasis and local recurrence after the surgical treatment of GCTB remains a challenge. Pathologically, stromal cells in GCTB are known as primary neoplastic cells and are recognized as incompletely differentiated preosteoblasts. Therefore, inducing GCTB stromal cells to differentiate into cells with a mature osteoblastic phenotype may stop tumor growth and recurrence. In this study, we aimed to investigate how simvastatin, a clinically approved and commonly used statin that has been known to promote the maturation of cells of the osteogenic lineage, affects GCTB stromal cells. We found that simvastatin effectively inhibited cell viability by suppressing proliferation and by inducing apoptosis in GCTB stromal cells. Moreover, simvastatin treatment upregulated the expression of genes related to osteogenic maturation, such as runt-related transcription factor 2, osteopontin, and osteocalcin, and increased the mineralization of the extracellular matrix in GCTB stromal cells. Ingenuity pathway analysis was used to discover that the vitamin D receptor pathway was involved in the simvastatin-induced osteogenic differentiation of GCTB stromal cells by upregulating the 1,25-dihydroxyvitamin D metabolism. Taken together, this in vitro study demonstrates the antitumor and differentiation-promoting effects of simvastatin on GCTB stromal cells and suggests the possibility of using simvastatin as an adjuvant therapy for GCTB. These findings support further clinical investigation of the efficacy of using simvastatin as an adjuvant therapy for GCTB to reduce recurrence and distant metastasis after surgical treatment. © 2019 Orthopedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:297-310, 2020.


Subject(s)
Giant Cell Tumor of Bone/drug therapy , Hypolipidemic Agents/therapeutic use , Simvastatin/therapeutic use , Cell Differentiation/drug effects , Cell Line, Tumor , Drug Screening Assays, Antitumor , Giant Cell Tumor of Bone/metabolism , Humans , Hypolipidemic Agents/pharmacology , Simvastatin/pharmacology , Stromal Cells/drug effects , Stromal Cells/metabolism , Vitamin D/analogs & derivatives , Vitamin D/metabolism
13.
J Plast Reconstr Aesthet Surg ; 73(3): 516-527, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31488377

ABSTRACT

BACKGROUND: Both mesenchymal stem cell-conditioned medium (MSC CM) and Botox have demonstrated therapeutic effects for hypertrophic scar (HS). It is unclear whether a synergistic effect occurs when these treatments are used in combination. We aimed to investigate the therapeutic effects of MSC CM and Botox alone when compared with those of a combined regimen on HS. METHODS: Fibroblasts from human HS were isolated and treated with Dulbecco's modified Eagle's medium (DMEM), MSCCM, or Botox alone or a combination of MSCCM and Botox. We also used an in vivo HS-buried null mice model to investigate the efficacy of combination treatment. RESULTS: The results demonstrated that the combination of MSC CM and Botox downregulated both mRNA and protein levels of type I collagen, type III collagen, and alpha-smooth muscle actin (α-SMA) in HS fibroblasts. The combined regimen also suppressed fibroblast proliferative activity, increased apoptosis, and displayed significant inhibitory effects on the contractile ability of HS fibroblasts compared to MSC CM, Botox, or DMEM alone. Using an in vivo HS-buried null mice model, significant scar weight reduction, cell apoptosis, and less α-SMA expression were observed from the combined regimen of MSC CM and Botox compared to those from the other groups. The combined regimen also significantly improved arrangement and deposition of collagen fibers. CONCLUSIONS: This study demonstrates that a combination of MSC CM and Botox exhibited a significant therapeutic effect compared to monotherapy. Clinical translation of this therapy should be further considered.


Subject(s)
Botulinum Toxins, Type A/therapeutic use , Cicatrix, Hypertrophic/therapy , Mesenchymal Stem Cell Transplantation/methods , Animals , Combined Modality Therapy , Fibroblasts , Humans , Mice , Mice, Inbred BALB C , Mice, Nude
14.
Stem Cell Res Ther ; 10(1): 275, 2019 08 28.
Article in English | MEDLINE | ID: mdl-31462299

ABSTRACT

BACKGROUND: Hypertrophic scars (HSs) are formed via an aberrant response to the wound healing process. HSs can be cosmetic or can result in functional problems. Prolonged proliferation and remodeling phases disrupt wound healing, leading to excessive collagen production and HS formation. However, there are currently no satisfactory drugs to prevent HS formation. Mesenchymal stem cell (MSC) conditioned medium (CM) has therapeutic effects on wound healing and preventing HS formation. Bone marrow concentrate (BMC) contains various growth factors and cytokines that are crucial for regeneration and has been applied in the clinical setting. In this study, we evaluated the effects of BMC-induced MSC CM on HS formation in a rabbit ear model. METHODS: We established a rabbit ear wound model by generating full-thickness wounds in the ears of rabbits (n = 12) and treated wounds with MSC CM, BMC CM, or BMC-induced MSC CM. Dermal fibroblasts from human hypertrophic scar were stimulated with transforming growth factor beta 1 (TGF-ß1) for 24 h and cultured in each culture medium for 72 h. We measured the hypertrophic scar (HS) formation during the skin regeneration by measuring the expression of several remodeling molecules and the effect of these conditioned media on active human HS fibroblasts. RESULTS: Our results showed that BMC-induced MSC CM had greater antifibrotic effects than MSC CM and BMC CM significantly attenuated HS formation in rabbits. BMC-induced MSC CM accelerated wound re-epithelization by increasing cell proliferation. Additionally, BMC-induced MSC CM also inhibited fibrosis by decreasing profibrotic gene and protein expression, promoting extracellular matrix turnover, inhibiting fibroblast contraction, and reversing myofibroblast activation. CONCLUSIONS: BMC-induced MSC CM modulated the proliferation and remodeling phases of wound healing, representing a potential wound healing agent and approach for preventing HS formation.


Subject(s)
Bone Marrow/metabolism , Cicatrix, Hypertrophic/metabolism , Culture Media, Conditioned/metabolism , Ear/pathology , Mesenchymal Stem Cells/metabolism , Wound Healing/physiology , Animals , Bone Marrow/physiology , Cell Proliferation/physiology , Cicatrix, Hypertrophic/pathology , Extracellular Matrix/metabolism , Extracellular Matrix/physiology , Female , Fibroblasts/metabolism , Fibroblasts/physiology , Mesenchymal Stem Cells/physiology , Mice , Mice, Inbred BALB C , Myofibroblasts/metabolism , Myofibroblasts/physiology , Rabbits , Skin/metabolism , Skin/pathology , Transforming Growth Factor beta1/metabolism
15.
Nat Commun ; 10(1): 1524, 2019 04 03.
Article in English | MEDLINE | ID: mdl-30944305

ABSTRACT

Tissues and cells in organism are continuously exposed to complex mechanical cues from the environment. Mechanical stimulations affect cell proliferation, differentiation, and migration, as well as determining tissue homeostasis and repair. By using a specially designed skin-stretching device, we discover that hair stem cells proliferate in response to stretch and hair regeneration occurs only when applying proper strain for an appropriate duration. A counterbalance between WNT and BMP-2 and the subsequent two-step mechanism are identified through molecular and genetic analyses. Macrophages are first recruited by chemokines produced by stretch and polarized to M2 phenotype. Growth factors such as HGF and IGF-1, released by M2 macrophages, then activate stem cells and facilitate hair regeneration. A hierarchical control system is revealed, from mechanical and chemical signals to cell behaviors and tissue responses, elucidating avenues of regenerative medicine and disease control by demonstrating the potential to manipulate cellular processes through simple mechanical stimulation.


Subject(s)
Hair/physiology , Macrophages/physiology , Regeneration/physiology , Animals , Bone Morphogenetic Protein 2 , Cell Differentiation/physiology , Cell Movement/physiology , Cell Proliferation , Chemokines/genetics , Chemokines/metabolism , Female , Hair/growth & development , Hair/metabolism , Hair Follicle/growth & development , Hair Follicle/metabolism , Hepatocyte Growth Factor/metabolism , Insulin-Like Growth Factor I/metabolism , Macrophages/metabolism , Mice, Inbred C57BL , Recombinant Proteins , Skin/cytology , Skin/metabolism , Stem Cells , Stress, Mechanical , Transforming Growth Factor beta
16.
PLoS One ; 13(11): e0207008, 2018.
Article in English | MEDLINE | ID: mdl-30395639

ABSTRACT

OBJECTIVE: Osteoporosis is a multifactorial disease associated with inflammation and hormone imbalance. It is noteworthy that dry eye syndrome shares a similar pathophysiology with osteoporosis. Both diseases are more prevalent among the elderly and females. Dry eye syndrome can result in impaired vision, which increases the risk of fall and fracture when osteoporosis exists. In this study, we investigated whether osteoporosis is associated with an increased risk of developing dry eye syndrome. METHODS: Claims data from the National Health Insurance Research Database (NHIRD) of Taiwan were used to conduct a retrospective population-based cohort study covering the period from January 1, 2000, to December 31, 2011. Multiple logistic regression was used to determine whether osteoporosis is an independent factor in the risk of developing dry eye syndrome, with risk estimates presented in the form of odds ratios (ORs). RESULTS: The exclusion of patients with specific autoimmune diseases and those younger than 50 years old resulted in 42,365 patients in the osteoporosis group and 147,460 patients in the comparison group during the study period. The number of patients newly diagnosed with dry eye syndrome was 6,478 (15.29%) in the osteoporosis group and 15,396 (10.44%) in the comparison group. The crude OR of patients with osteoporosis developing dry eye syndrome was 1.55 and the 95% confidence interval (95% CI) was 1.50-1.60. After adjusting for patients' age, sex, and underlying comorbidities, the adjusted OR was 1.26 and the 95% CI was 1.22-1.30. Subgroup analysis revealed this association in each age group and among females but not among males. CONCLUSIONS: Our results demonstrate that osteoporosis is a risk factor for the subsequent development of dry eye syndrome. Clinicians should be aware of the early symptoms of dry eye syndrome in osteoporotic patients in order to prevent further complications.


Subject(s)
Accidental Falls/prevention & control , Dry Eye Syndromes/diagnosis , Osteoporosis/diagnosis , Aged , Aged, 80 and over , Databases, Factual , Dry Eye Syndromes/complications , Dry Eye Syndromes/epidemiology , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Odds Ratio , Osteoporosis/complications , Retrospective Studies , Risk , Taiwan/epidemiology
17.
Sci Rep ; 8(1): 12913, 2018 08 27.
Article in English | MEDLINE | ID: mdl-30150652

ABSTRACT

While biophysical stimuli from polymeric matrices are known to significantly affect the fates of human mesenchymal stem cells (hMSCs), the stimulatory effects of nano-sized silicon-based matrices on hMSCs have not been thoroughly investigated. We previously demonstrated that vertically aligned, single-crystalline silicon nanowires (SiNWs) can control the osteogenicity of hMSCs via controllable spring constants from SiNWs matrix. However, other possible differentiation fates of hMSCs on SiNWs have not been explored. We hypothesize that tunable spring constant from artificial SiNWs matrices can direct different types of hMSC differentiations. The spring constants of tunable SiNW matrices can be consistently controlled by tuning the SiNW length. The results of gene expression and cell stiffness suggest that hMSCs differentiations are sensitive to our distinguishable spring constants from the SiNWs groups, and simultaneously conduct osteogenicity and adipogenicity. These findings suggest that SiNW matrices can regulate the fates of hMSCs when the SiNW characteristics are carefully tuned.


Subject(s)
Mesenchymal Stem Cells/cytology , Nanowires/chemistry , Silicon/chemistry , Cell Differentiation/physiology , Humans , Mesenchymal Stem Cells/metabolism , Microscopy, Electron, Scanning
18.
Biomed Res Int ; 2018: 9246529, 2018.
Article in English | MEDLINE | ID: mdl-29854810

ABSTRACT

PURPOSE: High tibial osteotomy (HTO) has been adopted as an effective surgery for medial degeneration of the osteoarthritis (OA) knee. However, satisfactory outcomes necessitate the precise creation and distraction of osteotomized wedges and the use of intraoperative X-ray images to continually monitor the wedge-related manipulation. Thus HTO is highly technique-demanding and has a high radiation exposure. We report a patient-specific instrument (PSI) guide for the precise creation and distraction of HTO wedge. METHODS: This study first parameterized five HTO procedures to serve as a design rationale for an innovative PSI guide. Preoperative X-ray and computed tomography- (CT-) scanning images were used to design and fabricate PSI guides for clinical use. The weight-bearing line (WBL) of the ten patients was shifted to the Fujisawa's point and instrumented using the TomoFix system. The radiological results of the PSI-guided HTO surgery were evaluated by the WBL percentage and tibial slope. RESULTS: All patients consistently showed an increased range of motion and a decrease in pain and discomfort at about three-month follow-up. This study demonstrates the satisfactory accuracy of the WBL adjustment and tibial slope maintenance after HTO with PSI guide. For all patients, the average pre- and postoperative WBL are, respectively, 14.2% and 60.2%, while the tibial slopes are 9.9 and 10.1 degrees. The standard deviations are 2.78 and 0.36, respectively, in postoperative WBL and tibial slope. The relative errors of the pre- and postoperative WBL percentage and tibial slope averaged 4.9% and 4.1%, respectively. CONCLUSION: Instead of using navigator systems, this study integrated 2D and 3D preoperative planning to create a PSI guide that could most likely render the outcomes close to the planning. The PSI guide is a precise procedure that is time-saving, radiation-reducing, and relatively easy to use. Precise osteotomy and good short-term results were achieved with the PSI guide.


Subject(s)
Osteotomy/instrumentation , Osteotomy/methods , Printing, Three-Dimensional/instrumentation , Tibia/surgery , Aged , Female , Humans , Knee Joint/surgery , Male , Middle Aged , Osteoarthritis, Knee/surgery , Postoperative Period , Radiography/methods , Range of Motion, Articular/physiology , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods , Weight-Bearing/physiology
19.
Int J Mol Sci ; 19(4)2018 Mar 29.
Article in English | MEDLINE | ID: mdl-29596344

ABSTRACT

Arsenite (As), a notorious toxic metal, is ubiquitously distributed in the earth and poses a serious threat to human health. Histopathological lesions of As intoxication are known as thromboangiitis obliterans, which are resistant to current treatment and often lead to lower limb amputation. In this study, we attempt to find that treatment with mesenchymal stem cells (MSCs) may be effective for As-induced vasculopathy. We first conducted an in vitro study with a co-culture system containing human MSCs and human umbilical vein endothelial cells (HUVECs) and treated individual and co-cultured cells with various concentrations of arsenite. We also designed an in vivo study in which Sprague Dawley (SD) rats received periodic intraperitoneal (IP) injections of 16 ppm arsenite for 12 weeks. MSCs were harvested from BALB/c mice that were transplanted via tail vein injection. We found that there was significantly higher cellular viability in human mesenchymal stem cells (hMSCs) than in HUVECs under concentrations of arsenite between 15 and 25 µM. The Annexin V apoptosis assay further confirmed this finding. Cytokine array assay for As-conditioned media revealed an elevated vascular endothelial growth factor (VEGF) level secreted by MSCs, which is crucial for HUVEC survival and was evaluated by an siRNA VEGF knockdown test. In the in vivo study, we demonstrated early apoptotic changes in the anterior tibial vessels of As-injected SD rats with a Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, but these apoptotic changes were less frequently observed upon MSCs transplantation, indicating that the cytoprotective effect of MSCs successfully protected against As-induced peripheral vasculopathy. The feasibility of MSCs to treat and /or prevent the progression of As-induced vasculopathy is justified. Further clinical studies are required to demonstrate the therapeutic efficacy of MSCs in patients suffering from As intoxication with vasculopathy.


Subject(s)
Arsenites/toxicity , Human Umbilical Vein Endothelial Cells/metabolism , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Vascular Diseases , Animals , Cell Survival , Gene Knockdown Techniques , Heterografts , Human Umbilical Vein Endothelial Cells/pathology , Humans , Mice , Mice, Inbred BALB C , Rats , Rats, Sprague-Dawley , Vascular Diseases/chemically induced , Vascular Diseases/genetics , Vascular Diseases/metabolism , Vascular Diseases/therapy , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
20.
Gastroenterology ; 154(1): 46-56, 2018 01.
Article in English | MEDLINE | ID: mdl-29107021

ABSTRACT

Liver transplantation is the only effective therapy for patients with decompensated cirrhosis and fulminant liver failure. However, due to a shortage of donor livers and complications associated with immune suppression, there is an urgent need for new therapeutic strategies for patients with end-stage liver diseases. Given their unique function in self-renewal and differentiation potential, stem cells might be used to regenerate damaged liver tissue. Recent studies have shown that stem cell-based therapies can improve liver function in a mouse model of hepatic failure. Moreover, acellular liver scaffolds seeded with hepatocytes produced functional bioengineered livers for organ transplantation in preclinical studies. The therapeutic potential of stem cells or their differentiated progenies will depend on their capacity to differentiate into mature and functional cell types after transplantation. It will also be important to devise methods to overcome their genomic instability, immune reactivity, and tumorigenic potential. We review directions and advances in the use of mesenchymal stem cells and their derived hepatocytes for liver regeneration. We also discuss the potential applications of hepatocytes derived from human pluripotent stem cells and challenges to using these cells in treating end-stage liver disease.


Subject(s)
End Stage Liver Disease/history , Mesenchymal Stem Cell Transplantation/history , Regenerative Medicine/history , End Stage Liver Disease/therapy , Hepatocytes/transplantation , History, 20th Century , History, 21st Century , Humans , Liver Regeneration
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