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1.
J Ocul Pharmacol Ther ; 39(10): 705-715, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37579061

RESUMO

Purpose: To investigate the clinical efficacy of omidenepag isopropyl (OMDI) among glaucoma patients in terms of increased intraocular pressure (IOP) changes through a meta-analysis. Methods: Studies investigating the clinical efficacy of OMDI toward glaucoma patients were systemically searched. Inclusion criteria include recruiting studies that consisted of glaucoma or normal tension glaucoma patients who received OMDI treatment at least 4 weeks in duration. The primary outcome was to compare changes in IOP levels at baseline before OMDI treatment and after OMDI treatment. Results: Six studies were included with a total of 358 eyes. Our results showed OMDI monotherapy resulted in significant decreased IOP among patients with ocular hypertension, with weighted mean difference post-OMDI treatment being -4.684 (95% confidence interval: -6.010 to -3.358) and I2 of 91.092%. Separate subgroup analyses also showed initial IOP greater than 21 mmHg and those within the age group greater than 65 years old to be correlated with significant reduction in IOP post-OMDI. Randomized control trial (RCTs) design was also found to be superior compared with non-RCT in terms of investigating IOP changes after OMDI. The country of origin of the recruited studies and OMDI dosage frequencies were also found to have no effect on overall IOP changes after OMDI treatment. Conclusions: The current meta-analysis indicates OMDI to be a clinically effective treatment for glaucoma patients in terms of lowering IOP levels.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Glaucoma de Baixa Tensão , Hipertensão Ocular , Humanos , Idoso , Glaucoma de Baixa Tensão/tratamento farmacológico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Pressão Intraocular , Glaucoma/tratamento farmacológico , Hipertensão Ocular/tratamento farmacológico , Resultado do Tratamento , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico
2.
J Med Internet Res ; 23(7): e23863, 2021 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34407500

RESUMO

BACKGROUND: Diabetic retinopathy (DR), whose standard diagnosis is performed by human experts, has high prevalence and requires a more efficient screening method. Although machine learning (ML)-based automated DR diagnosis has gained attention due to recent approval of IDx-DR, performance of this tool has not been examined systematically, and the best ML technique for use in a real-world setting has not been discussed. OBJECTIVE: The aim of this study was to systematically examine the overall diagnostic accuracy of ML in diagnosing DR of different categories based on color fundus photographs and to determine the state-of-the-art ML approach. METHODS: Published studies in PubMed and EMBASE were searched from inception to June 2020. Studies were screened for relevant outcomes, publication types, and data sufficiency, and a total of 60 out of 2128 (2.82%) studies were retrieved after study selection. Extraction of data was performed by 2 authors according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), and the quality assessment was performed according to the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Meta-analysis of diagnostic accuracy was pooled using a bivariate random effects model. The main outcomes included diagnostic accuracy, sensitivity, and specificity of ML in diagnosing DR based on color fundus photographs, as well as the performances of different major types of ML algorithms. RESULTS: The primary meta-analysis included 60 color fundus photograph studies (445,175 interpretations). Overall, ML demonstrated high accuracy in diagnosing DR of various categories, with a pooled area under the receiver operating characteristic (AUROC) ranging from 0.97 (95% CI 0.96-0.99) to 0.99 (95% CI 0.98-1.00). The performance of ML in detecting more-than-mild DR was robust (sensitivity 0.95; AUROC 0.97), and by subgroup analyses, we observed that robust performance of ML was not limited to benchmark data sets (sensitivity 0.92; AUROC 0.96) but could be generalized to images collected in clinical practice (sensitivity 0.97; AUROC 0.97). Neural network was the most widely used method, and the subgroup analysis revealed a pooled AUROC of 0.98 (95% CI 0.96-0.99) for studies that used neural networks to diagnose more-than-mild DR. CONCLUSIONS: This meta-analysis demonstrated high diagnostic accuracy of ML algorithms in detecting DR on color fundus photographs, suggesting that state-of-the-art, ML-based DR screening algorithms are likely ready for clinical applications. However, a significant portion of the earlier published studies had methodology flaws, such as the lack of external validation and presence of spectrum bias. The results of these studies should be interpreted with caution.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Algoritmos , Retinopatia Diabética/diagnóstico , Técnicas de Diagnóstico Oftalmológico , Humanos , Aprendizado de Máquina , Redes Neurais de Computação
3.
Clin Infect Dis ; 73(3): e773-e781, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33569576

RESUMO

BACKGROUND: There are no antiviral therapies for parainfluenza virus (PIV) infections. DAS181, a sialidase fusion protein, has demonstrated activity in in vitro and in animal models of PIV. METHODS: Adult immunocompromised patients diagnosed with PIV lower respiratory tract infection (LRTI) who required oxygen supplementation were randomized 2:1 to nebulized DAS181 (4.5 mg/day) or matching placebo for up to 10 days. Randomization was stratified by need for mechanical ventilation (MV) or supplemental oxygen (SO). The primary endpoint was the proportion of patients reaching clinical stability survival (CSS) defined as returning to room air (RTRA), normalization of vital signs for at least 24 hours, and survival up to day 45 from enrollment. RESULTS: A total of 111 patients were randomized to DAS181 (n = 74) or placebo (n = 37). CSS was achieved by 45.0% DAS181-treated patients in the SO stratum compared with 31.0% for placebo (P = .15), whereas patients on MV had no benefit from DAS181. The proportion of patients achieving RTRA was numerically higher for SO stratum DAS181 patients (51.7%) compared with placebo (34.5%) at day 28 (P = .17). In a post hoc analysis of solid organ transplant, hematopoietic cell transplantation within 1 year, or chemotherapy within 1 year, more SO stratum patients achieved RTRA on DAS181 (51.8%) compared with placebo (15.8%) by day 28 (P = .012). CONCLUSIONS: The primary endpoint was not met, but post hoc analysis of the RTRA component suggests DAS181 may have clinical activity in improving oxygenation in select severely immunocompromised patients with PIV LRTI who are not on mechanical ventilation. Clinical Trials Registration. NCT01644877.


Assuntos
Infecções por Paramyxoviridae , Infecções Respiratórias , Adulto , Animais , Humanos , Hospedeiro Imunocomprometido , Pulmão , Proteínas Recombinantes de Fusão , Infecções Respiratórias/tratamento farmacológico
4.
Crit Care Explor ; 2(10): e0263, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33134951

RESUMO

OBJECTIVES: Severe acute respiratory syndrome coronavirus 2 infections commonly lead to respiratory failure and potentially fatal systemic inflammation and organ failure. Nebulized DAS181, a host-directed biologics with sialidase activity, is an investigational drug with antiviral activities on parainfluenza and influenza under phase 3 and phase 2 development. The objective of this study (NCT04324489) is to investigate the safety and effects of nebulized DAS181 on hypoxic coronavirus disease 2019 patients. DESIGN: Single-center, prospective, open-label, compassionate use. SETTING: Renmin Hospital of Wuhan University, Department of Respiratory and Critical Care Medicine and Department of Infectious Diseases. SUBJECTS: Patients 18 to 70 years old who met Chinese criteria for severe coronavirus disease 2019 pneumonia and required supplemental oxygen but not on mechanical ventilator at screening. INTERVENTIONS: Nebulized DAS181 (4.5 mg) twice a day for 10 days. MEASUREMENTS AND MAIN RESULTS: Three male coronavirus disease 2019 hypoxic patients with bilateral lung involvement completed DAS181 treatment for 10 days. By day 14, all achieved return to room air (primary endpoint) and their nasopharyngeal swabs were negative for severe acute respiratory syndrome coronavirus 2. Clinical severity improved from severe coronavirus disease 2019 at baseline to moderate or mild disease by day 5, consistent with rapid reduction of inflammatory cytokines by days 2-3 and radiologic improvement by days 5-10. No DAS181-related adverse events were reported. CONCLUSIONS: Inhalation of DAS181 was well tolerated and potential clinical benefit of DAS181 on hypoxic coronavirus disease 2019 is the reduction of supplemental oxygen need. Efficacy and safety, including pharmacokinetics and viral studies of DAS181 in severe, hypoxic coronavirus disease 2019, should be examined by a double-blind, randomized controlled study.

5.
Sci Adv ; 6(6): eaay0264, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32076643

RESUMO

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.


Assuntos
Endoderma/citologia , Endoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , RNA Longo não Codificante/genética , Proteína Smad2/genética , Proteína Smad3/genética , Animais , Diferenciação Celular/genética , Linhagem Celular , Linhagem da Célula/genética , Células Cultivadas , Matriz Extracelular , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Modelos Biológicos , Especificidade de Órgãos/genética , Interferência de RNA , Transcriptoma
6.
Stem Cell Res Ther ; 10(1): 270, 2019 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-31445515

RESUMO

BACKGROUND: Testicular torsion is an urological emergency that may lead to infertility due to ischemic injury. Promptly surgical correction by orchiopexy is the only way to avoid infertility and no effective treatment for restoration of spermatogenesis. We previously reported that mesenchymal stem cells (MSCs), through local injection upon testicular torsion-detorsion, restored the spermatogenesis without differentiation into sperm. In this study, molecular mechanisms of MSCs in regulating germ cell activity induced by testicular torsion-detorsion were investigated. METHODS: Sixteen male Sprague-Dawley rats 6-8 weeks old received left testis 720° torsion for 3 h followed by detorsion with or without MSCs. Right inguinal skin incision without testicular torsion served as control. MSCs with 3 × 104 cells were locally injected into left testis 30 min before detorsion. Three days after the surgery, orchiectomy was executed and the testis, epididymis, and sperm were separated to each other. Functional assessments on sperm included counting sperm amount and sperm motility, staining F-actin, and quantifying adenosine triphosphate (ATP) content. The hallmarks of glycogenesis and glycolysis in each tissue segment were measured by Western blot. RESULTS: Testicular torsion-detorsion significantly decreased the amount of sperm, inhibited the motility, declined the F-actin expression, and reduced the content of ATP in sperm. Local injection of MSCs improved sperm function, particularly in sperm motility. With MSCs, ATP content and F-actin were preserved after testicular torsion-detorsion. MSCs significantly reversed the imbalance of glycolysis in sperm and testis induced by testicular torsion-detorsion, as evidenced by increasing the expression of phosphoglycerate kinase 2 and glyceraldehyde-3-phosphate dehydrogenase-spermatogenic, activating Akt, and increasing glycogen synthase kinase 3 (GSK3), which led to the increase in glycolysis cascades and ATP production. Human stem cell factor contributed the activation of Akt/GSK3 axis when sperm suffered from testicular torsion-detorsion-induced germ cell injury. CONCLUSIONS: Local injection of MSCs into a testis damaged by testicular torsion-detorsion restores sperm function mainly through the improvement of sperm motility and energy. MSCs reversed the imbalance of glycogenesis and glycolysis in sperm by regulating Akt/GSK3 axis. Thus, MSCs may potentially rescue torsion-detorsion-induced infertility via local injection.


Assuntos
Glucose/metabolismo , Células-Tronco Mesenquimais/metabolismo , Motilidade dos Espermatozoides/fisiologia , Torção do Cordão Espermático/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Actinas/metabolismo , Animais , Células Germinativas/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Isoenzimas/metabolismo , Masculino , Fosfoglicerato Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Espermatogênese/fisiologia
7.
Xenotransplantation ; 26(6): e12542, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31219208

RESUMO

BACKGROUND: Fulminant liver failure (FLF) is a life-threatening disease. METHODS: Lethal FLF was induced by ischemia-reperfusion (I-R) injury in mini-pigs, and MSCs were infused via splenic vein after reperfusion. RESULTS: Accumulated survival within 28 days was significantly improved by MSCs (P = 0.0348). Notably, MSCs maintained blood-gas homeostasis in the first 24 hours and prevented FLF-induced elevation of prothrombin time, international normalized ratio, and creatinine and ammonia levels in the first 3 days. With MSCs, serum levels of liver enzymes gradually decreased after 3 days, and platelet count was back to normal at 1 week of FLF. MSCs promoted liver regeneration within 2 weeks and differentiated into functional hepatocytes at 2-4 weeks after transplantation, evidenced by increase in Ki67-positive cells, detectable human hepatocyte growth factor, human vascular endothelial growth factor, human hepatocyte-specific antigen, and human albumin-expressing cells in the liver at different time points. Reactive oxidative species (ROS) were accumulated after FLF and eliminated at 4 weeks after MSC transplantation. CONCLUSIONS: Together, MSCs prolong the survival and prevent lethal sequelae of I-R injury-induced FLF by maintenance of liver-function homeostasis and rescue of ROS in the acute stage and by homing and differentiation into hepatocytes in the subacute stage.


Assuntos
Hepatócitos/citologia , Falência Hepática Aguda/terapia , Fígado/citologia , Células-Tronco Mesenquimais/citologia , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Masculino , Suínos , Transplante Heterólogo/métodos , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Biomaterials ; 190-191: 1-10, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391798

RESUMO

Mesenchymal stem cell (MSC) is mechanosensitive and the respond to mechanical force is pattern specific. We previously reported that oscillatory shear stress at 0.5 ±â€¯4 dyne/cm2 guided MSCs polarity vertical to net flow direction before apolaric stage at 30 min resulting in phosphorylation of ß-catenin and inhibition of Wnt signaling. This time, we explored laminar shear stress (LS) at 0.5 dyne/cm2 polarized MSCs by guiding F-actin orientation parallel to the flow direction before apolarity at 30 min accompanied with activation of Wnt signaling. Time-dependent microarray analysis supported cell-cell junctional complex of MSCs was the major mechanosensor on MSCs to respond 0.5 dyne/cm2 LS. Three-dimensional immunofluorescence image confirmed LS promoting ß-catenin nuclear localization during 15 min to 1 h with a peak at 30 min. Functional analysis of proteomic study on MSC with 30 min LS stimulation indicated that upregulation of ß-catenin downstream proteins related to cardiovascular development, endothelial cell protection and angiogenesis. Conditioned medium from MSCs with 30 min LS stimulation improved the viability of human endothelial cells from oxidative damage. In conclusion, 0.5 dyne/cm2 LS on MSCs for 30 min guides MSCs lack of polarity and promotes ß-catenin nuclear translocation favoring Wnt activation and paracrine cardiovascular support.


Assuntos
Núcleo Celular/metabolismo , Células-Tronco Mesenquimais/citologia , beta Catenina/metabolismo , Actinas/análise , Actinas/metabolismo , Polaridade Celular , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana , Humanos , Células-Tronco Mesenquimais/metabolismo , Mapas de Interação de Proteínas , Estresse Mecânico , Via de Sinalização Wnt , beta Catenina/análise
9.
Oncol Lett ; 14(2): 1315-1322, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28789346

RESUMO

Cancer is a multifactorial disease, and imbalances of the immune response and sex-associated features are considered risk factors for certain types of cancer. The present study aimed to assess whether ankylosing spondylitis (AS), an immune disorder that predominantly affects young adult men, is associated with an increased risk of cancer. Using the Taiwan National Health Insurance Research Database, a cohort of patients diagnosed with AS between 2000 and 2008 who had no history of cancer prior to enrollment was established (n=5,452). Age- and sex-matched patients without AS served as controls (n=21,808). The results revealed that the overall incidence of cancer was elevated in patients with AS [standardized incidence ratio (SIR), 1.15; 95% confidence interval (CI), 1.03-1.27]. AS carried an increased risk of hematological malignancy in both sexes, colon cancer in females and bone and prostate cancer in males. Young patients with AS (≤35 years) and patients with a Charlson comorbidity index (CCI) ≥2 experienced a higher incidence of cancer (males, SIR 1.92, and 95% CI 1.04-3.26; females, SIR 2.00 and 95% CI 1.46-5.50). The cancer risk was increased during the first 3 years following the diagnosis of AS (SIR 1.49, 95% CI 1.29-1.71), and overall cancer-free survival was significantly decreased in patients with AS patients of both sexes (P<0.0001). Therefore, AS was found to be associated with an increased risk of cancer. All AS patients must be screened for hematological malignancies, for prostate and bone cancer in males, and for colon cancer in females, particularly younger patients with a CCI ≥2.

10.
Cell Transplant ; 26(3): 503-512, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28195034

RESUMO

Ataxia is one of the most devastating symptoms of many neurodegenerative disorders. As of today, there is not any effective treatment to retard its progression. Mesenchymal stem cells (MSCs) have shown promise in treating neurodegenerative diseases. We hereby report the results of a phase I/IIa clinical study conducted in Taiwan to primarily evaluate the safety, tolerability, and, secondarily, the possible efficacy of intravenous administration of allogeneic adipose tissue-derived MSCs from healthy donors. Six patients with spinocerebellar ataxia type 3 and one with multiple system atrophy-cerebellar type were included in this open-label study with intravenous administration of 106 cells/kg body weight. The subjects were closely monitored for 1 year for safety (vital signs, complete blood counts, serum biochemical profiles, and urinalysis) and possible efficacy (scale for assessment and rating of ataxia and sensory organization testing scores, metabolite ratios on the brain magnetic resonance spectroscopy, and brain glucose metabolism of 18-fluorodeoxyglucose using positron emission tomography). No adverse events related to the injection of MSCs during the 1-year follow-up were observed. The intravenous administration of allogeneic MSCs seemed well tolerated. Upon study completion, all patients wished to continue treatment with the allogeneic MSCs. We conclude that allogeneic MSCs given by intravenous injection seems to be safe and tolerable in patients with spinocerebellar ataxia type 3, thus supporting advancement of the clinical development of allogeneic MSCs for the treatment of spinocerebellar ataxias (SCAs) in a randomized, double-blind, placebo-controlled phase II trials.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Ataxias Espinocerebelares/terapia , Transplante Homólogo/métodos , Adulto , Idoso , Encéfalo/patologia , Células Cultivadas , Método Duplo-Cego , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Stem Cell Res Ther ; 7(1): 120, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27542358

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSCs) are multipotent and have great potential in cell therapy. Previously we reported the differentiation potential of human MSCs into hepatocytes in vitro and that these cells can rescue fulminant hepatic failure. However, the conventional static culture method neither maintains growth factors at an optimal level constantly nor removes cellular waste efficiently. In addition, not only is the duration of differentiating hepatocyte lineage cells from MSCs required to improve, but also the need for a large number of hepatocytes for cell therapy has not to date been addressed fully. The purpose of this study is to design and develop an innovative microfluidic device to overcome these shortcomings. METHODS: We designed and fabricated a microfluidic device and a culture system for hepatic differentiation of MSCs using our protocol reported previously. The microfluidic device contains a large culture chamber with a stable uniform flow to allow homogeneous distribution and expansion as well as efficient induction of hepatic differentiation for MSCs. RESULTS: The device enables real-time observation under light microscopy and exhibits a better differentiation efficiency for MSCs compared with conventional static culture. MSCs grown in the microfluidic device showed a higher level of hepatocyte marker gene expression under hepatic induction. Functional analysis of hepatic differentiation demonstrated significantly higher urea production in the microfluidic device after 21 days of hepatic differentiation. CONCLUSIONS: The microfluidic device allows the generation of a large number of MSCs and induces hepatic differentiation of MSCs efficiently. The device can be adapted for scale-up production of hepatic cells from MSCs for cellular therapy.


Assuntos
Técnicas de Cocultura/métodos , Hepatócitos/citologia , Células-Tronco Mesenquimais/citologia , Microfluídica/métodos , Animais , Biomarcadores/metabolismo , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Células Cultivadas , Expressão Gênica/fisiologia , Hepatócitos/metabolismo , Fígado/citologia , Fígado/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL
12.
Oncol Lett ; 12(2): 1007-1010, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27446385

RESUMO

The aim of the present study was to report a rare case of single-clone, immunoglobulin heavy chain (IgH)-rearranged mucosa-associated lymphoid tissue (MALT) lymphoma in the conjunctiva, with nasal cavity dissemination through the nasolacrimal duct. A 24-year-old female was diagnosed with MALT lymphoma of the nasal cavity at the Department of Otolaryngology, Wan Fang Medical Center, Taipei Medical University (Tapei, Taiwan) in October 2008. A biopsy of the relapsing conjunctival lesion revealed a MALT lymphoma by pathological staining, while a single-clone, IgH-rearranged tumor lesion in the nasal cavity and conjunctiva was confirmed using continuous sinus computed tomography scans and polymerase chain reaction. Tumor lesions were negative for Helicobacter pylori and Chlamydia infection, but exhibited bilateral neck lymph node dissemination. A combination of radiation therapy (a total dosage of 46.8 Gray, in two phases covering the left lacrimal sac, nasal cavity and bilateral neck region) and topical ciprofloxacin plus steroid (0.3% ciprofloxacin 4 times a day and betamethasone eye ointment before sleep for 1 month) was provided as an effective therapeutic strategy, and no recurrence was found in the next 3 years. The nasolacrimal duct serves as a channel for conjunctival tumor spreading and is easily neglected. IgH-involved translocation in MALT lymphoma is a factor in the progression of the disease, and aggressive combination therapy is essential for a high-risk, disseminated IgH-rearranged MALT lymphoma.

13.
Stem Cells ; 34(10): 2525-2535, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27250866

RESUMO

The healing of a corneal epithelial defect is essential for preventing infectious corneal ulcers and subsequent blindness. We previously demonstrated that mesenchymal stem cells (MSCs) in the corneal stroma, through a paracrine mechanism, yield a more favorable therapeutic benefit for corneal wound re-epithelialization than do MSCs in the corneal epithelium. In this study, MSCs were grown on a matrix with the rigidity of the physiological human vitreous (1 kPa), corneal epithelium (8 kPa), or corneal stroma (25 kPa) for investigating the role of corneal tissue rigidity in MSC functions regarding re-epithelialization promotion. MSC growth on a 25-kPa dish significantly promoted the wound healing of human corneal epithelial (HCE-T) cells. Among growth factors contributing to corneal epithelial wound healing, corneal stromal rigidity selectively enhanced transforming growth factor-beta (TGF-ß) secretion from MSCs. Inhibitors of TGF-ß pan receptor, TGF-ß receptor 1, and Smad2 dose dependently abrogated MSC-mediated HCE-T wound healing. Furthermore, MSCs growth on a matrix with corneal stromal rigidity enhanced the ability of themselves to promote corneal re-epithelialization by activating matrix metalloproteinase (MMP) expression and integrin ß1 production in HCE-T cells through TGF-ß signaling pathway activation. Smad2 activation resulted in the upregulation of MMP-2 and -13 expression in HCE-T cells, whereas integrin ß1 production favored a Smad2-independent TGF-ß pathway. Altogether, we conclude that corneal stromal rigidity is a critical factor for MSC-induced promotion of corneal re-epithelialization. The activation of the TGF-ß signaling pathway, which maintains the balance between integrin and MMP expression, in HCE-T cells is the major pathway responsible for MSC-mediated wound healing. Stem Cells 2016;34:2525-2535.


Assuntos
Lesões da Córnea/patologia , Lesões da Córnea/terapia , Substância Própria/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Cicatrização , Linhagem Celular , Proliferação de Células , Humanos , Integrina beta1/metabolismo , Metaloproteinases da Matriz/metabolismo , Células-Tronco Mesenquimais/metabolismo , Reepitelização , Proteína Smad2/metabolismo , Regulação para Cima
14.
Sci Rep ; 6: 21253, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26884253

RESUMO

The spatial boundary condition (SBC) arising from the surrounding microenvironment imposes specific geometry and spatial constraints that affect organogenesis and tissue homeostasis. Mesenchymal stromal cells (MSCs) sensitively respond to alterations of mechanical cues generated from the SBC. However, mechanical cues provided by a three-dimensional (3D) environment are deprived in a reductionist 2D culture system. This study investigates how SBC affects osteogenic differentiation of MSCs using 3D scaffolds with monodispersed pores and homogenous spherical geometries. MSCs cultured under SBCs with diameters of 100 and 150 µm possessed the greatest capability of osteogenic differentiation. This phenomenon was strongly correlated with MSC morphology, organization of actin cytoskeleton, and distribution of focal adhesion involving α2 and α5 integrins. Further silencing either α2 or α5 integrin significantly reduced the above mentioned mechanosensitivity, indicating that the α2 and α5 integrins as mechano-sensitive molecules mediate MSCs' ability to provide enhanced osteogenic differentiation in response to different spherical SBCs. Taken together, the findings provide new insights regarding how MSCs respond to mechanical cues from the surrounding microenvironment in a spherical SBC, and such biophysical stimuli should be taken into consideration in tissue engineering and regenerative medicine in conjunction with biochemical cues.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Osteogênese , Nicho de Células-Tronco , Actinas/metabolismo , Adesão Celular , Técnicas de Cultura de Células , Sobrevivência Celular , Adesões Focais , Humanos , Integrina alfa2/metabolismo , Integrina alfa5/metabolismo , Esferoides Celulares , Alicerces Teciduais
15.
Stem Cell Res Ther ; 6: 113, 2015 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-26025454

RESUMO

INTRODUCTION: Testicular torsion is a urological emergency and infertility is a common complication due to ischemic injury. Surgical reduction and orchiopexy is indicated, but to date there is no effective method for restoration of spermatogenesis. The effects of mesenchymal stem cells (MSCs) on acute tissue injury have been demonstrated, and the abilities of paracrine support, differentiation and immune-modulation may benefit to testicular torsion-induced infertility. We investigate the therapeutic efficacy and the mechanisms of MSCs in testicular torsion-induced germ cell injury when injected locally. METHODS: Six to eight-week-old Sprague-Dawley rats received surgical 720 degree torsion for 3 hours, followed by detorsion on the left testis. 20 µl of phosphate-buffered saline (PBS) without or with 3 x 10(4) MSCs from human orbital fat tissues (OFSCs) were given for 10 rats, respectively, via local injection into the left testis 30 minutes before detorsion. 20 µl of PBS injection for 6 rats with surgical exposure without torsion served as sham control. Histopathology with Johnsen's score analysis, Western blot analysis for superoxide dismutase 2, Bax, Caspase-3, human insulin growth factor-1 and human stem cell factor, malondialdehyde (MDA) assay in testis and plasma, hormones level including testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) by ELISA Kits, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and fluorescence staining for P450, Sox-9 and VASA were performed. RESULTS: Animals were sacrificed and bilateral orchiectomy was performed 7 days after torsion-detorsion. Local injections of OFSCs prevented torsion-induced infertility judging from Johnsen's score. TUNEL assay and Western blot analysis on caspase 3 and Bax demonstrated that OFSCs prevented ischemic/reperfusion induced intrinsic apoptosis. MDA assay revealed that OFSCs significantly reduced the oxidative stress in the damaged testicular tissues. After the OFSC injection, serum testosterone secretion was increased, while the elevation of FSH triggered by testicular injury was balanced. OFSCs also produced stem cell factor in the damaged testis. Immunofluorescence staining revealed that most transplanted cells surrounded the Leydig cells. Some of transplanted cells differentiated into p450 expressing cells within 7 days. CONCLUSIONS: Local injection of allogenic MSCs before surgical detorsion is a simple, clinical friendly procedure to rescue torsion-induced infertility.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Torção do Cordão Espermático/terapia , Testículo/patologia , Tecido Adiposo/citologia , Animais , Apoptose , Caspase 3/metabolismo , Hormônio Foliculoestimulante/sangue , Células Germinativas/citologia , Células Germinativas/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio Luteinizante/sangue , Masculino , Malondialdeído/metabolismo , Células-Tronco Mesenquimais/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Testosterona/sangue , Transplante Heterólogo
16.
Stem Cell Res Ther ; 4(3): 72, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23769140

RESUMO

INTRODUCTION: Topical administration of eye drops is the major route for drug delivery to the cornea. Orbital fat-derived stem cells (OFSCs) possess an in vitro corneal epithelial differentiation capacity. Both the safety and immunomodulatory ability of systemic OFSC transplantation were demonstrated in our previous work. In this study, we investigated the safety, therapeutic effect, and mechanism(s) of topical OFSC administration in an extensive alkali-induced corneal wound. METHODS: Corneal injury was created by contact of a piece of 0.5 N NaOH-containing filter paper on the corneal surface of a male Balb/c mouse for 30 s. The area of the filter paper covered the central 70% or 100% of the corneal surface. OFSCs (2 × 10(5)) in 5 µl phosphate-buffered saline (PBS) were given by topical administration (T) twice a day or by two intralimbal (IL) injections in the right cornea, while 5 µl of PBS in the left cornea served as the control. RESULTS: Topical OFSCs promoted corneal re-epithelialization of both the limbal-sparing and limbal-involved corneal wounds. In the first three days, topical OFSCs significantly reduced alkali-induced corneal edema and stromal infiltration according to a histopathological examination. Immunohistochemistry and immunofluorescence staining revealed that transplanted cells were easily detectable in the corneal epithelium, limbal epithelium and stroma, but only some of transplanted cells at the limbal epithelium had differentiated into cytokeratin 3-expressing cells. OFSCs did not alter neutrophil (Ly6G) levels in the cornea, but significantly reduced macrophage (CD68) infiltration and inducible nitrous oxide synthetase (iNOS) production during acute corneal injury as quantified by a Western blot analysis. Continuous topical administration of OFSCs for seven days improved corneal transparency, and this was accompanied by diffuse stromal engraftment of transplanted cells and differentiation into p63-expressing cells at the limbal area. The therapeutic effect of the topical administration of OFSCs was superior to that of the IL injection. OFSCs from the IL injection clustered in the limbal area and central corneal epithelium, which was associated with a persistent corneal haze. CONCLUSIONS: Topical OFSC administration is a simple, non-surgical route for stem cell delivery to promote corneal tissue regeneration through ameliorating acute inflammation and corneal epithelial differentiation. The limbal area serves as a niche for OFSCs differentiating into corneal epithelial cells in the first week, while the stroma is a potential site for anti-inflammation of OFSCs. Inhibition of corneal inflammation is related to corneal transparency.


Assuntos
Córnea/fisiologia , Lesões da Córnea/terapia , Regeneração , Transplante de Células-Tronco , Células-Tronco/citologia , Tecido Adiposo/citologia , Administração Tópica , Animais , Diferenciação Celular , Células Cultivadas , Lesões da Córnea/patologia , Epitélio Corneano/patologia , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Células-Tronco/metabolismo , Transplante Homólogo , Cicatrização
17.
Biomaterials ; 34(8): 1911-20, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23261211

RESUMO

Light-emitting diode (LED) irradiation is potentially a photostimulator to manipulate cell behavior by opsin-triggered phototransduction and thermal energy supply in living cells. Directional stem cell motility is critical for the efficiency and specificity of stem cells in tissue repair. We explored that green LED (530 nm) irradiation directed the human orbital fat stem cells (OFSCs) to migrate away from the LED light source through activation of extracellular signal-regulated kinases (ERK)/MAP kinase/p38 signaling pathway. ERK inhibitor selectively abrogated light-driven OFSC migration. Phosphorylation of these kinases as well as green LED irradiation-induced cell migration was facilitated by increasing adenosine triphosphate (ATP) production in OFSCs after green LED exposure, and which was thermal stress-independent mechanism. OFSCs, which are multi-potent mesenchymal stem cells isolated from human orbital fat tissue, constitutionally express three opsins, i.e. retinal pigment epithelium-derived rhodopsin homolog (RRH), encephalopsin (OPN3) and short-wave-sensitive opsin 1 (OPN1SW). However, only two non-visual opsins, i.e. RRH and OPN3, served as photoreceptors response to green LED irradiation-induced OFSC migration. In conclusion, stem cells are sensitive to green LED irradiation-induced directional cell migration through activation of ERK signaling pathway via a wavelength-dependent phototransduction.


Assuntos
Movimento Celular/efeitos da radiação , Eletrônica , Luz , Órbita/citologia , Células-Tronco/citologia , Células-Tronco/efeitos da radiação , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Córnea/citologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/efeitos da radiação , Temperatura Alta , Humanos , Transdução de Sinal Luminoso/efeitos dos fármacos , Transdução de Sinal Luminoso/efeitos da radiação , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Células-Tronco/efeitos dos fármacos , Células-Tronco/enzimologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação
18.
J Biomed Sci ; 19: 70, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-22849814

RESUMO

Magnolia officinalis has been widely used in traditional Chinese medicine. Magnolol, an active component isolated from Magnolia officinalis, is known to be a cardiovascular protector since 1994. The multiplex mechanisms of magnolol on cardiovascular protection depends on cell types and dosages, and will be reviewed and discussed in this article. Magnolol under low and moderate dosage possesses the ability to protect heart from ischemic/reperfusion injury, reduces atherosclerotic change, protects endothelial cell against apoptosis and inhibits neutrophil-endothelial adhesion. The moderate to high concentration of magnolol mainly acts on smooth muscle cells and platelets. Magnolol induces apoptosis in vascular smooth muscle cells at moderate concentration and inhibits proliferation at moderate and high concentration. High concentration of magnolol also abrogates platelet activation, aggregation and thrombus formation. Magnolol also serves as an smooth muscle relaxant only upon the high concentration. Oral intake of magnolol to reach the therapeutic level for cardiovascular protection is applicable, thus makes magnolol an agent of great potential for preventing cardiovascular diseases in high-risk patients.


Assuntos
Compostos de Bifenilo/uso terapêutico , Sistema Cardiovascular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Lignanas/uso terapêutico , Miócitos Cardíacos , Miócitos de Músculo Liso , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/química , Humanos , Inflamação/prevenção & controle , Lignanas/química , Magnolia/química , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos
19.
Biomaterials ; 33(20): 5013-22, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22513273

RESUMO

Extracellular stimuli imposed on stem cells enable efficient initiation of mechanotransductive signaling to regulate stem cell fates; however, how such physical cues conferred by the stereo-topographical matrix govern the fate of stem cells still remains unknown. The purpose of this study is to delineate the effects of stereotopography and its various relevant physical properties on the fate regulation of human mesenchymal stem cells (hMSCs). Stereo-topographical silicon nanowires (SiNWs) that were precisely controlled with respect to their various dimensions and their growth orientation were used in this study. hMSCs cultured on stereo SiNWs of different lengths in the absence of biochemical osteogenic induction cues displayed a spherical and less-elongated morphology and showed an approximately 10% loss of cell viability compared to those grown on two-dimensional (2-D) flat Si. Moreover, osteogenic gene expression of COL1A1 and Runx2 in hMSCs cultured on the shortest SiNWs was significantly higher than those grown on the longer SiNWs and 2-D flat Si. hMSCs grown on shorter SiNWs also demonstrated higher expression levels for F-actin, phosphorylated focal adhesion kinase (pFAK), vinculin and alpha 2 integrin. Stereo-topographical cues provided by SiNWs are able to regulate osteogenic differentiation of hMSCs via cytoskeleton remodeling and this is correlated with the differential expression of alpha 2/beta 1 integrin heterodimers and the focal adhesion molecules pFAK and vinculin. The findings in this study provide insights in terms of the design of stereo-topographical structures for use in tissue engineering, bone regeneration and relevant medical applications.


Assuntos
Células-Tronco Mesenquimais/citologia , Nanofios , Silício/química , Sequência de Bases , Fenômenos Biomecânicos , Adesão Celular , Divisão Celular , Linhagem da Célula , Primers do DNA , Imunofluorescência , Proteína-Tirosina Quinases de Adesão Focal/genética , Humanos , Integrinas/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase
20.
J Biomed Sci ; 18: 30, 2011 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-21569331

RESUMO

Salvianolic acids are the most abundant water-soluble compounds extracted from Radix Salvia miltiorrhiza (Danshen). In China, Danshen has been wildly used to treat cardiovascular diseases for hundreds of years. Salvianolic acids, especially salvianolic acid A (Sal A) and salvianolic acid B (Sal B), have been found to have potent anti-oxidative capabilities due to their polyphenolic structure. Recently, intracellular signaling pathways regulated by salvianolic acids in vascular endothelial cells, aortic smooth muscle cells, as well as cardiomyocytes, have been investigated both in vitro and in vivo upon various cardiovascular insults. It is discovered that the cardiovascular protection of salvianolic acids is not only because salvianolic acids act as reactive oxygen species scavengers, but also due to the reduction of leukocyte-endothelial adherence, inhibition of inflammation and metalloproteinases expression from aortic smooth muscle cells, and indirect regulation of immune function. Competitive binding of salvianolic acids to target proteins to interrupt protein-protein interactions has also been found to be a mechanism of cardiovascular protection by salvianolic acids. In this article, we review a variety of studies focusing on the above mentioned mechanisms. Besides, the target proteins of salvianolic acids are also described. These results of recent advances have shed new light to the development of novel therapeutic strategies for salvianolic acids to treat cardiovascular diseases.


Assuntos
Benzofuranos/farmacologia , Ácidos Cafeicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Lactatos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Fenantrolinas/farmacologia , Salvia miltiorrhiza/metabolismo , Animais , Aorta/efeitos dos fármacos , Benzofuranos/química , Ácidos Cafeicos/química , Medicamentos de Ervas Chinesas/química , Humanos , Lactatos/química , Fenantrolinas/química , Espécies Reativas de Oxigênio/metabolismo , Salvia miltiorrhiza/química
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