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1.
FASEB J ; 38(17): e23892, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39230563

RESUMO

Mesenchymal stromal stem cells (MSCs) or skeletal stem cells (SSCs) play a major role in tissue repair due to their robust ability to differentiate into osteoblasts, chondrocytes, and adipocytes. Complex cell signaling cascades tightly regulate this differentiation. In osteogenic differentiation, Runt-related transcription factor 2 (RUNX2) and ALP activity are essential. Furthermore, during the latter stages of osteogenic differentiation, mineral formation mediated by the osteoblast occurs with the secretion of a collagenous extracellular matrix and calcium deposition. Activation of nuclear factor erythroid 2-related factor 2 (NRF2), an important transcription factor against oxidative stress, inhibits osteogenic differentiation and mineralization via modulation of RUNX2 function; however, the exact role of NRF2 in osteoblastogenesis remains unclear. Here, we demonstrate that NRF2 activation in human bone marrow-derived stromal cells (HBMSCs) suppressed osteogenic differentiation. NRF2 activation increased the expression of STRO-1 and KITLG (stem cell markers), indicating NRF2 protects HBMSCs stemness against osteogenic differentiation. In contrast, NRF2 activation enhanced mineralization, which is typically linked to osteogenic differentiation. We determined that these divergent results were due in part to the modulation of cellular calcium flux genes by NRF2 activation. The current findings demonstrate a dual role for NRF2 as a HBMSC maintenance factor as well as a central factor in mineralization, with implications therein for elucidation of bone formation and cellular Ca2+ kinetics, dystrophic calcification and, potentially, application in the modulation of bone formation.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais , Fator 2 Relacionado a NF-E2 , Osteoblastos , Osteogênese , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Diferenciação Celular/fisiologia , Osteoblastos/metabolismo , Osteoblastos/citologia , Calcificação Fisiológica/fisiologia , Células Cultivadas , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética
2.
Nanoscale ; 15(45): 18457-18472, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37941481

RESUMO

Clay nanoparticles, in particular synthetic smectites, have generated interest in the field of tissue engineering and regenerative medicine due to their utility as cross-linkers for polymers in biomaterial design and as protein release modifiers for growth factor delivery. In addition, recent studies have suggested a direct influence on the osteogenic differentiation of responsive stem and progenitor cell populations. Relatively little is known however about the mechanisms underlying nanoclay bioactivity and in particular the cellular processes involved in nanoclay-stem cell interactions. In this study we employed confocal microscopy, inductively coupled plasma mass spectrometry and transmission electron microscopy to track the interactions between clay nanoparticles and human bone marrow stromal cells (hBMSCs). In particular we studied nanoparticle cellular uptake mechanisms and uptake kinetics, intracellular trafficking pathways and the fate of endocytosed nanoclay. We found that nanoclay particles present on the cell surface as µm-sized aggregates, enter hBMSCs through clathrin-mediated endocytosis, and their uptake kinetics follow a linear increase with time during the first week of nanoclay addition. The endocytosed particles were observed within the endosomal/lysosomal compartments and we found evidence for both intracellular degradation of nanoclay and exocytosis as well as an increase in autophagosomal activity. Inhibitor studies indicated that endocytosis was required for nanoclay upregulation of alkaline phosphatase activity but a similar dependency was not observed for autophagy. This study into the nature of nanoclay-stem cell interactions, in particular the intracellular processing of nanosilicate, may provide insights into the mechanisms underlying nanoclay bioactivity and inform the successful utilisation of clay nanoparticles in biomaterial design.


Assuntos
Células-Tronco Mesenquimais , Nanopartículas , Humanos , Osteogênese , Argila , Engenharia Tecidual , Materiais Biocompatíveis , Nanopartículas/química
3.
Medicina (Kaunas) ; 59(6)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37374297

RESUMO

Background and Objectives: With the emergence of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), it has become necessary to identify the implant shell type patients have received. Therefore, an immediate, reliable method for identifying a breast implant shell type is essential. Evidence-based research and applying a real-world technique that identifies the surface topographic information of the inserted breast implants, without surgery, has become of paramount importance for breast implant physicians. Methods and Materials: A review of the medical records of 1901 patients who received 3802 breast implants and subsequently received an ultrasound-assisted examination was performed. All patients received not only a breast cancer examination but also a high-resolution ultrasonography (HRUS) assisted examination of the device at a single center between 31 August 2017 and 31 December 2022. Results: Most patients had breast implants within 10 years (77.7%) of the examination. Of the 3802 implants screened, 2034 (53.5%) were identified with macro-textured shell topography in ultrasonography. A macrotextured shell type implant was used in 53.5% of cases and a smooth type in 42.7% of cases. Seventy-three (1.9%) breast implant shell types could not be identified due to ruptures. However, 250 breast implant shell types could be identified despite rupture cases (6.5%). Conclusions: HRUS was found to be a useful and reliable image modality for identifying various surface shell types of breast implants. The shell type information would be helpful to patients who lack information about their breast implants and are concerned about BIA-ALCL.


Assuntos
Implante Mamário , Implantes de Mama , Neoplasias da Mama , Feminino , Humanos , Implante Mamário/métodos , Implantes de Mama/efeitos adversos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Ultrassonografia
4.
Adv Healthc Mater ; 12(22): e2300226, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37166052

RESUMO

Myriad lung diseases are life threatening and macrophages play a key role in both physiological and pathological processes. Macrophages have each pro-/anti-inflammatory phenotype, and each lung disease can be aggravated by over-polarized macrophage. Therefore, development of a method capable of mediating the macrophage phenotype is one of the solutions for lung disease treatment. For mediating the phenotype of macrophages, the pulmonary delivery system (PDS) is widely used due to its advantages, such as high efficiency and accessibility of the lungs. However, it has a low drug delivery efficiency ironically because of the perfect lung defense system consisting of the mucus layer and airway macrophages. In this study, zwitterion-functionalized poly(lactide-co-glycolide) (PLGA) inhalable microparticles (ZwPG) are synthesized to increase the efficiency of the PDS. The thin layer of zwitterions formed on PLGA surface has high nebulizing stability and show high anti-mucus adhesion and evasion of macrophages. As a reprogramming agent for macrophages, ZwPG containing dexamethasone (Dex) and pirfenidone (Pir) are treated to over-polarized M2 macrophages. As a result, a synergistic effect of Dex/Pir induces reprogramming of M2 macrophage to pro-inflammatory phenotypes.


Assuntos
Pneumopatias , Macrófagos , Humanos , Fenótipo , Pulmão , Nebulizadores e Vaporizadores
5.
Vet Sci ; 10(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977223

RESUMO

Multi-organ dysfunction following cardiac arrest is associated with poor outcome as well as high mortality. The kidney, one of major organs in the body, is susceptible to ischemia and reperfusion; however, there are few studies on renal ischemia and reperfusion injury (IRI) following the return of spontaneous circulation (ROSC) after cardiac arrest. Risperidone, an atypical antipsychotic drug, has been discovered to have some beneficial effects beyond its original effectiveness. Therefore, the aim of the present study was to investigate possible therapeutic effects of risperidone on renal IRI following cardiac arrest. Rats were subjected to cardiac arrest induced by asphyxia for five minutes followed by ROSC. When serum biochemical analyses were examined, the levels of serum blood urea nitrogen, creatinine, and lactate dehydrogenase were dramatically increased after cardiac arrest, but they were significantly reduced by risperidone administration. Histopathology was examined using hematoxylin and eosin staining. Histopathological injury induced by cardiac arrest was apparently attenuated by risperidone administration. Furthermore, alterations in pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor-α) and anti-inflammatory cytokines (interleukin-4 and interleukin-13) were examined by immunohistochemistry. Pro-inflammatory and anti-inflammatory cytokine immunoreactivities were gradually and markedly increased and decreased, respectively, in the kidneys following cardiac arrest; however, risperidone administration after cardiac arrest significantly attenuated the increased pro-inflammatory cytokine immunoreactivities and the decreased anti-inflammatory cytokine immunoreactivities. Collectively, our current results revealed that, in rats, risperidone administration after cardiac arrest protected kidneys from IRI induced by cardiac arrest and ROSC through anti-inflammatory effects.

6.
Front Cell Neurosci ; 16: 895750, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246521

RESUMO

The stimulation of autophagy or lysosomes has been considered therapeutic for neurodegenerative disorders because the accumulation of misfolded proteins is commonly observed in the brains of individuals with these diseases. Although zinc is known to play critical roles in the functions of lysosomes and autophagy, the mechanism behind this regulatory relationship remains unclear. Therefore, in this study, we examined which mechanism is involved in zinc-mediated activation of autophagy and lysosome. Exposure to zinc at a sub-lethal concentration activated autophagy in a concentration-dependent manner in mRFP-GFP-LC3-expressing H4 glioma cells. Zinc also rescued the blocking of autophagic flux arrested by pharmaceutical de-acidification. Co-treatment with zinc attenuated the chloroquine (CQ)-induced increase in the number and size of mRFP-GFP-LC3 puncta in H4 cells and accumulation of p62 by CQ or ammonium chloride in both H4 and mouse cerebrocortical cultures. Zinc rapidly induced the expression of cathepsin B (CTSB) and cathepsin D (CTSD), representative lysosomal proteases in neurons, which appeared likely to be mediated by transcription factor EB (TFEB). We observed the translocation of TFEB from neurite to nucleus and the dephosphorylation of TFEB by zinc. The addition of cycloheximide, a chemical inhibitor of protein synthesis, inhibited the activity of CTSB and CTSD at 8 h after zinc exposure but not at 1 h, indicating that only late lysosomal activation was dependent on the synthesis of CTSB and CTSD proteins. At the very early time point, the activation of cathepsins was mediated by an increased assembly of V-ATPase on lysosomes and resultant lysosomal acidification. Finally, considering that P301L mutation in tau protein causes frontotemporal dementia through aggressive tau accumulation, we investigated whether zinc reduces the accumulation of protein aggregates in SK-N-BE(2)-C neuroblastoma cells expressing wild-type tau or mutant P301L-tau. Zinc markedly attenuated the levels of phosphorylated tau and total tau as well as p62 in both wild-type and mutant tau-overexpressing cells. We also observed that zinc was more effective than rapamycin at inducing TFEB-dependent CTSB and CTSD expression and V-ATPase-dependent lysosomal acidification and CTSB/CTSD activation. These results suggest that the regulation of zinc homeostasis could be a new approach for developing treatments for neurodegenerative diseases, including Alzheimer's and Parkinson's.

7.
Cells ; 11(15)2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35954179

RESUMO

Isolating a large quantity of high-quality human islets is a prerequisite for diabetes research. Human islets are typically isolated from the pancreases of brain-dead donors, making research difficult due to low availability. Pancreas tissue discarded after surgical resection may be a good alternative source of islet cells. To test this hypothesis, we isolated islets from discarded surgical specimens and evaluated the islet yield and quality as well as islet cell preparations. Eighty-two segmental pancreases were processed using the Ricordi automated method, and islet yield and quality were investigated. The mean age of patients was 54.6, and the cohort included 32 diabetes patients. After purification, partially resected pancreases yielded an average of 59,593 ± 56,651 islet equivalents (IEQs) and 2546 IEQ/g of digested pancreas, with 71.5 ± 21% purity. Multivariate analysis revealed that diabetes (p = 0.0046) and the lobe used (p = 0.0156) significantly altered islet yield. Islets transplanted into diabetic mice displayed good viability and in vitro glucose responses, DNA/RNA quality, mitochondrial function, and glucose control, even though these results were dependent on islet quality. Isolated cells also maintained high viability and function even after cryopreservation. Our findings indicate that pancreatic tissue discarded after surgery can be a valuable source of islets for diabetes research.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Humanos , Transplante das Ilhotas Pancreáticas/métodos , Camundongos , Pâncreas , Doadores de Tecidos
8.
Cell Death Differ ; 29(11): 2137-2150, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35462559

RESUMO

Protein S-nitrosylation is known to regulate enzymatic function. Here, we report that nitric oxide (NO)-related species can contribute to Alzheimer's disease (AD) by S-nitrosylating the lysosomal protease cathepsin B (forming SNO-CTSB), thereby inhibiting CTSB activity. This posttranslational modification inhibited autophagic flux, increased autolysosomal vesicles, and led to accumulation of protein aggregates. CA-074Me, a CTSB chemical inhibitor, also inhibited autophagic flux and resulted in accumulation of protein aggregates similar to the effect of SNO-CTSB. Inhibition of CTSB activity also induced caspase-dependent neuronal apoptosis in mouse cerebrocortical cultures. To examine which cysteine residue(s) in CTSB are S-nitrosylated, we mutated candidate cysteines and found that three cysteines were susceptible to S-nitrosylation. Finally, we observed an increase in SNO-CTSB in both 5XFAD transgenic mouse and flash-frozen postmortem human AD brains. These results suggest that S-nitrosylation of CTSB inhibits enzymatic activity, blocks autophagic flux, and thus contributes to AD pathogenesis.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Animais , Humanos , Camundongos , Catepsina B , Agregados Proteicos , Doenças Neurodegenerativas/genética , Proteínas/metabolismo , Doença de Alzheimer/metabolismo , Cisteína , Óxido Nítrico
9.
Bone ; 159: 116389, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35301163

RESUMO

The past decade has seen a growing appreciation for the role of the innate immune response in mediating repair and biomaterial directed tissue regeneration. The long-held view of the host immune/inflammatory response as an obstacle limiting stem cell regenerative activity, has given way to a fresh appreciation of the pivotal role the macrophage plays in orchestrating the resolution of inflammation and launching the process of remodelling and repair. In the context of bone, work over the past decade has established an essential coordinating role for macrophages in supporting bone repair and sustaining biomaterial driven osteogenesis. In this review evidence for the role of the macrophage in bone regeneration and repair is surveyed before discussing recent biomaterial and drug-delivery based approaches that target macrophage modulation with the goal of accelerating and enhancing bone tissue regeneration.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Macrófagos/fisiologia , Osteogênese , Cicatrização
10.
Cells ; 9(9)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878048

RESUMO

Islet cell transplantation is considered an ideal treatment for insulin-deficient diabetes, but implantation sites are limited and show low graft survival. Cell sheet technology and adipose-derived stem cells (ADSCs) can be useful tools for improving islet cell transplantation outcomes since both can increase implantation efficacy and graft survival. Herein, the optimal transplantation site in diabetic mice was investigated using islets and stem cell sheets. We constructed multi-layered cell sheets using rat/human islets and human ADSCs. Cell sheets were fabricated using temperature-responsive culture dishes. Islet/ADSC sheet (AI sheet) group showed higher viability and glucose-stimulated insulin secretion than islet-only group. Compared to islet transplantation alone, subcutaneous AI sheet transplantation showed better blood glucose control and CD31+ vascular traits. Because of the adhesive properties of cell sheets, AI sheets were easily applied on liver and peritoneal surfaces. Liver or peritoneal surface grafts showed better glucose control, weight gain, and intraperitoneal glucose tolerance test (IPGTT) profiles than subcutaneous site grafts using both rat and human islets. Stem cell sheets increased the therapeutic efficacy of islets in vivo because mesenchymal stem cells enhance islet function and induce neovascularization around transplanted islets. The liver and peritoneal surface can be used more effectively than the subcutaneous site in future clinical applications.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Experimental/terapia , Ilhotas Pancreáticas/metabolismo , Transplante de Células-Tronco/métodos , Células-Tronco/metabolismo , Animais , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
11.
Artigo em Inglês | MEDLINE | ID: mdl-32565421

RESUMO

OBJECTIVE: Esterified collagen (EC) can be functionalized with heparin to enhance islet graft stability. Growth factors secreted by human adipose-derived stem cells (hADSCs) can bind efficiently to EC-heparin (EC-Hep), which enhances revascularization and cell protection. We investigated the therapeutic potential of a combined heparin-esterified collagen-hADSC (HCA)-islet sheet to enhance islet engraftment. RESEARCH DESIGN AND METHODS: This study was designed to assess the efficiency of using EC-Hep as a scaffold for subcutaneous islet transplantation in diabetic athymic mice. After the hADSC-cocultured islets were seeded in the EC-Hep scaffold, islet function was measured by glucose-stimulated insulin secretion test and growth factors in the culture supernatants were detected by protein array. Islet transplantation was performed in mice, and graft function and survival were monitored by measuring the blood glucose levels. ß-Cell mass and vascular densities were assessed by immunohistochemistry. RESULTS: The EC-Hep composite allowed sustained release of growth factors. Secretion of growth factors and islet functionality in the HCA-islet sheet were significantly increased compared with the control groups of islets alone or combined with native collagen. In vivo, stable long-term glucose control by the graft was achieved after subcutaneous transplantation of HCA-islet sheet due to enhanced capillary network formation around the sheet. CONCLUSIONS: The findings indicate the potential of the HCA-islet sheet to enhance islet revascularization and engraftment in a hADSC dose-dependent manner, following clinical islet transplantation for the treatment of diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Animais , Colágeno , Diabetes Mellitus Experimental/terapia , Heparina , Camundongos , Células-Tronco
12.
Int J Mol Sci ; 21(9)2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32397660

RESUMO

Previous studies in our lab revealed that chemical zinc chelation or zinc transporter 3 (ZnT3) gene deletion suppresses the clinical features and neuropathological changes associated with experimental autoimmune encephalomyelitis (EAE). In addition, although protective functions are well documented for AMP-activated protein kinase (AMPK), paradoxically, disease-promoting effects have also been demonstrated for this enzyme. Recent studies have demonstrated that AMPK contributes to zinc-induced neurotoxicity and that 1H10, an inhibitor of AMPK, reduces zinc-induced neuronal death and protects against oxidative stress, excitotoxicity, and apoptosis. Here, we sought to evaluate the therapeutic efficacy of 1H10 against myelin oligodendrocyte glycoprotein 35-55-induced EAE. 1H10 (5 µg/kg) was intraperitoneally injected once per day for the entire experimental course. Histological evaluation was performed three weeks after the initial immunization. We found that 1H10 profoundly reduced the severity of the induced EAE and that there was a remarkable suppression of demyelination, microglial activation, and immune cell infiltration. 1H10 also remarkably inhibited EAE-associated blood-brain barrier (BBB) disruption, MMP-9 activation, and aberrant synaptic zinc patch formation. Furthermore, the present study showed that long-term treatment with 1H10 also reduced the clinical course of EAE. Therefore, the present study suggests that zinc chelation and AMPK inhibition with 1H10 may have great therapeutic potential for the treatment of multiple sclerosis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Quelantes/farmacologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Zinco/toxicidade , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Barreira Hematoencefálica/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Células Cultivadas , Quelantes/química , Doenças Desmielinizantes/tratamento farmacológico , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Imuno-Histoquímica , Macrófagos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação , Medula Espinal/metabolismo , Medula Espinal/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
13.
Biomacromolecules ; 21(6): 2096-2103, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32267672

RESUMO

Because nitric oxide (NO) gas is an endogenously produced signaling molecule related to numerous physiological functions, manystudies have been conducted to develop NO delivery systems for potential biomedical applications. However, NO is a reactive radical gas molecule that has a very short life-time and readily transforms into nitrogen oxide species via reaction with oxygen species. Therefore, it is necessary to develop an NO delivery carrier that allows local release of the NO gas at the site of application. In this study, Laponite (LP) nanoclay was used to fabricate an NO delivery carrier through the formation of Laponite-polyamine (LP-PAn) composites. The Laponite clay and pentaethylenehexamine (PEHA) formed a macromolecular structure by electrostatic interaction and the nitric oxide donor, N-diazeniumdiolate (NONOates), was synthesized into the LP-PAn composite. We investigated the conformation of the LP-PAn composite structure and the NO donor formation by ζ potential, X-ray diffraction, and UV-vis and Fourier transform infrared (FT-IR) spectroscopies and also by analyzing the NO release profile. Additionally, we confirmed the applicability in biomedical applications via a cell viability and in vitro endothelial cell tube formation assay.


Assuntos
Hidrogéis , Óxido Nítrico , Poliaminas , Silicatos , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Korean J Parasitol ; 58(6): 647-652, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33412768

RESUMO

Clonorchis sinensis is the most common fish-borne intestinal parasite in Korea. The aim of the present investigation was to survey the status of C. sinensis infection and analyze associated risk factors in residents of Haman-gun, Gyeongsangnam-do. A total of 5,114 residents from 10 administrative towns/villages voluntarily agreed to participate in the study, which comprised fecal examination, a questionnaire survey for risk factors, ultrasonography, and enzymelinked immunosorbent assay for cancer biomarker detection in the blood. We detected C. sinensis eggs in 5.3% of the subjects. By region, Gunbuk-myeon had the highest number of residents with C. sinensis eggs. The infection rate and intensity were higher in male than in female residents. Based on the risk factor questionnaire, infection was highly associated with drinking, a history of C. sinensis infection, and the practice of eating of raw freshwater fish. Extension of the bile duct, infection intensity, and cancer biomarker detection significantly correlated with the presence of eggs in the study population. In conclusion, the development of feasible, long-term control policies and strategies for the elimination of C. sinensis in Korea is still required.


Assuntos
Clonorquíase/epidemiologia , Clonorquíase/parasitologia , Clonorchis sinensis , Comportamento Alimentar/fisiologia , Peixes/parasitologia , Adulto , Idoso , Animais , Estudos de Casos e Controles , Clonorquíase/prevenção & controle , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , República da Coreia/epidemiologia , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários
15.
Biofabrication ; 11(3): 035027, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-30991370

RESUMO

Bioprinting of living cells is rapidly developing as an advanced biofabrication approach to engineer tissues. Bioinks can be extruded in three-dimensions (3D) to fabricate complex and hierarchical constructs for implantation. However, a lack of functionality can often be attributed to poor bioink properties. Indeed, advanced bioinks encapsulating living cells should: (i) present optimal rheological properties and retain 3D structure post fabrication, (ii) promote cell viability and support cell differentiation, and (iii) localise proteins of interest (e.g. vascular endothelial growth factor (VEGF)) to stimulate encapsulated cell activity and tissue ingrowth upon implantation. In this study, we present the results of the inclusion of a synthetic nanoclay, Laponite® (LPN) together with a gelatin methacryloyl (GelMA) bioink and the development of a functional cell-instructive bioink. A nanocomposite bioink displaying enhanced shape fidelity retention and interconnected porosity within extrusion-bioprinted fibres was observed. Human bone marrow stromal cell (HBMSC) viability within the nanocomposite showed no significant changes over 21 days of culture in LPN-GelMA (85.60 ± 10.27%), compared to a significant decrease in GelMA from 7 (95.88 ± 2.90%) to 21 days (55.54 ± 14.72%) (p < 0.01). HBMSCs were observed to proliferate in LPN-GelMA with a significant increase in cell number over 21 days (p < 0.0001) compared to GelMA alone. HBMSC-laden LPN-GelMA scaffolds supported osteogenic differentiation evidenced by mineralised nodule formation, including in the absence of the osteogenic drug dexamethasone. Ex vivo implantation in a chick chorioallantoic membrane model, demonstrated excellent integration of the bioink constructs in the vascular chick embryo after 7 days of incubation. VEGF-loaded LPN-GelMA constructs demonstrated significantly higher vessel penetration than GelMA-VEGF (p < 0.0001) scaffolds. Integration and vascularisation was directly related to increased drug absorption and retention by LPN-GelMA compared to LPN-free GelMA. In summary, a novel light-curable nanocomposite bioink for 3D skeletal regeneration supportive of cell growth and growth factor retention and delivery, evidenced by ex vivo vasculogenesis, was developed with potential application in hard and soft tissue reparation.


Assuntos
Gelatina/química , Tinta , Nanocompostos/química , Neovascularização Fisiológica , Osteogênese , Silicatos/química , Animais , Bioimpressão , Bovinos , Proliferação de Células , Sobrevivência Celular , Galinhas , Membrana Corioalantoide/metabolismo , Humanos , Hidrogéis/química , Células-Tronco Mesenquimais/citologia , Metacrilatos/química , Muramidase/metabolismo , Porosidade , Soroalbumina Bovina/metabolismo , Suínos , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Mol Brain ; 12(1): 18, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30866990

RESUMO

A number of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis, share intra- and/or extracellular deposition of protein aggregates as a common core pathology. While the species of accumulating proteins are distinct in each disease, an increasing body of evidence indicates that defects in the protein clearance system play a crucial role in the gradual accumulation of protein aggregates. Among protein degradation systems, the endosome-autophagosome-lysosome pathway (EALP) is the main degradation machinery, especially for large protein aggregates. Lysosomal dysfunction or defects in fusion with vesicles containing cargo are commonly observed abnormalities in proteinopathic neurodegenerative diseases. In this review, we discuss the available evidence for a mechanistic connection between components of the EALP-especially lysosomes-and neurodegenerative diseases. We also focus on lysosomal pH regulation and its significance in maintaining flux through the EALP. Finally, we suggest that raising cAMP and free zinc levels in brain cells may be beneficial in normalizing lysosomal pH and EALP flux.


Assuntos
AMP Cíclico/metabolismo , Lisossomos/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Zinco/metabolismo , Animais , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos
17.
Medicine (Baltimore) ; 98(5): e14104, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30702564

RESUMO

RATIONALE: The horseshoe anomaly of the vermiform appendix is extremely rare. Preoperative confirmation of this anomaly is difficult; therefore, routine procedures, such as appendectomy, may become unexpectedly challenging when such anomalies are encountered during the surgical process. PATIENT CONCERNS: A 33-year-old man presented with abdominal pain in the right lower abdomen owing to acute appendicitis confirmed via computed tomography. Immediate laparoscopic appendectomy was decided as the method for treatment. DIAGNOSIS: Horseshoe anomaly was diagnosed as a gross finding during surgery. INTERVENTION: First, the appendiceal base was resected and appendectomy was performed via the retrograde method because the appendiceal tip was curled behind the cecum. However, it was discovered that the appendiceal tip was connected to the lateral part of the ascending colon and showed a horseshoe-shaped anomaly. The second appendiceal base arising from the ascending colon was also ligated, and the appendectomy was completed without any further complications. OUTCOMES: After successful completion of appendectomy, the patient was discharged without any complications 2 days later. LESSONS: An appendiceal anomaly is rarely seen during appendectomy or other forms of abdominal surgery; however, the ability of surgeons to both recognize and categorize an appendiceal anomaly is crucial if detected during surgery. After successfully recognizing the horseshoe anomaly of the appendix, it is important to know that 2 appendiceal base ligations will be required to complete the surgery successfully.


Assuntos
Apendicectomia/métodos , Apendicite/cirurgia , Apêndice/anormalidades , Adulto , Apendicite/diagnóstico por imagem , Apêndice/diagnóstico por imagem , Apêndice/patologia , Colo/patologia , Humanos , Laparoscopia , Masculino , Tomografia Computadorizada por Raios X
18.
Medicine (Baltimore) ; 98(3): e14063, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30653118

RESUMO

RATIONALE: The brain, liver, adrenal glands, and bone are the most common sites of metastatic disease in patients with lung cancer. Symptomatic gastrointestinal metastases are rare. In the present report, we describe a rare case of a patient with intestinal obstruction due to solitary colonic metastasis from primary lung adenocarcinoma, wherein the intestinal obstruction was the first symptom of lung cancer. PATIENT CONCERNS: A 74-year-old man was admitted to the emergency room with abdominal pain and vomiting, and abdominal computed tomography (CT) indicated obstruction of the ascending colon due to a huge mass. DIAGNOSIS: The ascending colon cancer was found to be a metastatic adenocarcinoma based on the results of the pathology report. Chest CT and positron emission tomography-CT were performed to identify the cancer origin site. Moreover, immunohistochemical staining of the tissue specimen for thyroid transcription factor 1, cytokeratin 7 (CK7), and CK20 and CT-guided gun biopsy of the lung mass confirmed the presence of an adenocarcinoma that originated from the lung. INTERVENTION: Right hemicolectomy was performed as the primary treatment. OUTCOMES: The patient recovered without any problems due to the surgery itself. However, malignant pleural effusion deteriorated, and no additional palliative chemotherapy was performed. LESSONS: Patients with malignant bowel obstruction along with lung infiltration should be suspected of not only colon cancer with lung metastasis, but also lung cancer with colon metastasis.


Assuntos
Adenocarcinoma/complicações , Neoplasias do Colo/complicações , Obstrução Intestinal/etiologia , Neoplasias Pulmonares/patologia , Adenocarcinoma/secundário , Idoso , Neoplasias do Colo/secundário , Humanos , Masculino
19.
Xenotransplantation ; 26(1): e12451, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252163

RESUMO

BACKGROUND: Genetic reprogramming is a powerful method for altering cell properties and inducing differentiation. However, even if the same gene is reprogrammed, the results vary among cells. Therefore, a better possible strategy involves treating cells with factors that further stimulate differentiation while using stem cells with the same tissue origin. This study aimed to increase induction efficiency and insulin production in reprogrammed cells using a combination of factors that promote cell differentiation. METHODS: Porcine pancreatic cells were cultured to obtain mesenchymal stem cells expressing pancreatic cell-specific markers through sequential passages. The characteristics of these cells were identified, and the M3 gene (Pdx1, Ngn3, MafA) was reprogrammed to induce differentiation into insulin-producing cells. Additionally, the differentiation efficiency of insulin-producing cells was compared by treating reprogrammed cells with a differentiation-promoting factor. RESULTS: Mesenchymal stem cells isolated from porcine pancreatic tissues expressed exocrine cell markers, including amylase and cytokeratin 18, and most cells continuously expressed the beta cell transcription factors Ngn3 and NeuroD. Reprogramming of the M3 gene resulted in differentiation into insulin-producing cells. Moreover, significantly increased insulin and glucagon expressions were observed in the suitable induction medium, and the characteristic beta cell transcription factors Pdx1, Ngn3, and MafA were expressed at levels as high as those in pancreatic islet cells. CONCLUSIONS: Differentiation into insulin-producing cells represents an alternative therapy for insufficient pancreatic islet cells when treating diabetes. Therefore, cells with the characteristics of the target cell should be used to improve differentiation efficiency by creating an environment that promotes reprogramming and differentiation.


Assuntos
Meios de Cultura , Células Secretoras de Insulina/citologia , Insulina/metabolismo , Células-Tronco Mesenquimais/citologia , Transplante Heterólogo , Animais , Diferenciação Celular/genética , Células Cultivadas , Glucagon/metabolismo , Humanos , Pâncreas/metabolismo , Suínos , Transplante Heterólogo/métodos
20.
Adv Healthc Mater ; 7(15): e1800331, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29911340

RESUMO

Laponite nanoparticles have attracted attention in the tissue engineering field for their protein interactions, gel-forming properties, and, more recently, osteogenic bioactivity. Despite growing interest in the osteogenic properties of Laponite, the application of Laponite colloidal gels to host the osteogenic differentiation of responsive stem cell populations remains unexplored. Here, the potential to harness the gel-forming properties of Laponite to generate injectable bioactive microenvironments for osteogenesis is demonstrated. A diffusion/dialysis gelation method allows the rapid formation of stable transparent gels from injectable, thixotropic Laponite suspensions in physiological fluids. Upon contact with buffered saline or blood serum, nanoporous gel networks exhibiting, respectively, fivefold and tenfold increases in gel stiffness are formed due to the reorganization of nanoparticle interactions. Laponite diffusion gels are explored as osteogenic microenvironments for skeletal stem cell containing populations. Laponite films support cell adhesion, proliferation, and differentiation of human bone marrow stromal cells in 2D. Laponite gel encapsulation significantly enhances osteogenic protein expression compared with 3D pellet culture controls. In both 2D and 3D conditions, cell associated mineralization is strongly enhanced. This study demonstrates that Laponite diffusion gels offer considerable potential as biologically active and clinically relevant bone tissue engineering scaffolds.


Assuntos
Géis/química , Osteogênese/fisiologia , Silicatos/química , Adesão Celular/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Microambiente Celular/fisiologia , Humanos , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos
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