Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
Add more filters










Publication year range
1.
Int J Mol Sci ; 23(15)2022 Jul 30.
Article in English | MEDLINE | ID: mdl-35955581

ABSTRACT

A gelatin-based hydrogel scaffold with highly uniform pore size and biocompatibility was fabricated for cartilage tissue engineering using microfluidic 3D-foaming technology. Mainly, bubbles with different diameters, such as 100 µm and 160 µm, were produced by introducing an optimized nitrogen gas and gelatin solution at an optimized flow rate, and N2/gelatin bubbles were formed. Furthermore, a cross-linking agent (1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide, EDC) was employed for the cross-linking reaction of the gelatin-based hydrogel scaffold with uniform bubbles, and then the interface between the close cells were broken by degassing. The pore uniformity of the gelatin-based hydrogel scaffolds was confirmed by use of a bright field microscope, conjugate focus microscope and scanning electron microscope. The in vitro degradation rate, mechanical properties, and swelling rate of gelatin-based hydrogel scaffolds with highly uniform pore size were studied. Rabbit knee cartilage was cultured, and its extracellular matrix content was analyzed. Histological analysis and immunofluorescence staining were employed to confirm the activity of the rabbit knee chondrocytes. The chondrocytes were seeded into the resulting 3D porous gelatin-based hydrogel scaffolds. The growth conditions of the chondrocyte culture on the resulting 3D porous gelatin-based hydrogel scaffolds were evaluated by MTT analysis, live/dead cell activity analysis, and extracellular matrix content analysis. Additionally, a dynamic culture of cartilage tissue was performed, and the expression of cartilage-specific proteins within the culture time was studied by immunofluorescence staining analysis. The gelatin-based hydrogel scaffold encouraged chondrocyte proliferation, promoting the expression of collagen type II, aggrecan, and sox9 while retaining the structural stability and durability of the cartilage after dynamic compression and promoting cartilage repair.


Subject(s)
Gelatin , Tissue Engineering , Animals , Biocompatible Materials/chemistry , Cartilage , Cells, Cultured , Chondrocytes/metabolism , Gelatin/chemistry , Hydrogels/chemistry , Microfluidics , Porosity , Rabbits , Tissue Engineering/methods , Tissue Scaffolds/chemistry
2.
J Chin Med Assoc ; 84(4): 368-374, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33784264

ABSTRACT

BACKGROUND: Delayed extubation is one of postoperative pulmonary complications (PPCs). Preoperative pulmonary function test (PFT) is an important assessment for patients undergoing lung resection. Volume-oriented incentive spirometry (IS) is one of physiotherapies to prevent PPCs. Preoperative PFT and IS volume (IS-v) can reflect the physiologic conditions of respiratory system in patients planning to undergo lung resection. However, the relationship between preoperative PFT/IS-v and delayed extubation in patients undergoing lung resection remains unclear. The study investigated the risk factors and impact of delayed extubation after lung resection. We aimed to achieve early recognition of patients being at a higher risk for developing postoperative delayed extubation after lung resection. METHODS: This retrospective observational 4-year cohort study was conducted in a medical center, Taiwan. A total of 353 enrolled patients receiving thoracic surgery for lung resection were further categorized into the delayed extubation (n = 142, 40%) and non-delayed extubation (n = 211, 60%) groups. RESULTS: In multivariate logistic regression analyses, age >65 years (adjusted odds ratio [AOR]: 2.60; 95% confidence interval [CI], 1.52-4.45), American Society of Anesthesiologists score >2 (AOR: 1.72; 95% CI, 1.05-2.82), anesthesia time >6hrs (AOR: 1.80; 95% CI, 1.13-2.88), pneumonectomy (AOR: 5.58; 95% CI, 1.62-19.19), and IS-v/inspiratory capacity (IC) ratio (AOR: 2.07; 95% CI, 1.16-3.68) were associated with delayed extubation after lung resection (all p < 0.05). Patients with delayed extubation were significantly associated with a higher proportion of other pulmonary complications, reintubation, mortality, and prolonged intensive care unit and hospital stays. CONCLUSION: Older age, poor general health status, longer anesthesia time, pneumonectomy, and IS-v/IC ratio could be the independent factors predictive for delayed extubation after lung resection, which was in turn associated with worse outcomes. Preoperative PFT and IS-v were valuable for early recognition of patients being at a higher risk for developing postoperative delayed extubation after lung resection.


Subject(s)
Airway Extubation , Pneumonectomy/methods , Respiratory Function Tests , Spirometry , Aged , Female , Humans , Lung/surgery , Male , Middle Aged , Retrospective Studies , Risk Factors , Time Factors
3.
Horm Behav ; 127: 104881, 2021 01.
Article in English | MEDLINE | ID: mdl-33127368

ABSTRACT

Social eavesdropping is a low-cost learning mechanism by which individuals extract relevant social information from social interactions between conspecifics, thereby gaining subsequent advantages in information gathering and usage. The aim of this study was to take advantage of a new hamster model of social eavesdropping to investigate behavioral consequences and neural activity in male hamsters during social eavesdropping. Bystander hamsters with a defeat experience were exposed to either a fighting interaction, a neutral encounter, or control conditions for 3 days of social eavesdropping. In Experiment 1, bystanders in the fight and neutral groups displayed more information gathering behaviors and less nonsocial behavior than control hamsters. The fight group displayed significant increases in c-Fos-positive neurons in the anterior mid-cingulate cortex (aMCC) and the piriform cortex. A slight but not significant group difference was found in their serum cortisol levels. In vivo local field potential oscillation recordings in Experiment 2 revealed that bystanders in the fight group had more delta oscillations in the aMCC during information gathering across 3-day social eavesdropping than those in the other 2 groups. Experiment 3 confirmed that 20 min of social eavesdropping on Day 1 was sufficient to evoke differential behavioral outcomes, and the behavioral responses became more prominent after 3 days of social eavesdropping. Collectively, our study confirmed that male golden hamsters are capable of social eavesdropping and indicated the involvement of aMCC delta oscillations in social eavesdropping.


Subject(s)
Mesocricetus/physiology , Nervous System/anatomy & histology , Social Behavior , Acoustic Stimulation/psychology , Animals , Behavior, Animal/physiology , Cricetinae , Hydrocortisone/metabolism , Male , Motivation/physiology , Neurons/cytology , Neurons/physiology , Proto-Oncogene Proteins c-fos/metabolism , Social Learning/physiology , Synaptic Transmission/physiology
4.
Sci Rep ; 10(1): 14478, 2020 09 02.
Article in English | MEDLINE | ID: mdl-32879354

ABSTRACT

Frailty is common among older people and results in adverse health outcomes. We investigated whether exposure to PM2.5 is associated with frailty. This cross-sectional study involved 20,606 community-dwelling participants aged ≥ 65 years, residing in New Taipei City, Taiwan. Analytic data included phenotypic frailty, disease burden by Charlson Comorbidity Index (CCI), urban or rural residence, and household income. PM2.5 exposure was calculated from air quality monitoring records, with low exposure defined as the lowest quartile of the study population. 1,080 frail participants (5.2%) were older, predominantly female, had more comorbidities, lived rurally, and had low PM2.5 exposure (all p < 0.001). In multinomial logistic regression analyses, the likelihood of high PM2.5 exposure was higher in prefrail (OR 1.4, 95% CI 1.3-1.5) and frail adults (OR 1.5, 95% CI 1.2-1.9) than in robust individuals, with stronger associations in those who were male (frail: OR 2.1, 95% CI 1.5-3.1; prefrail: OR 2.2, 95% CI 1.9-2.6), ≥ 75 years old (frail: OR 1.8, 95% CI 1.3-2.4; prefrail: OR 1.5, 95% CI 1.3-1.8), non-smokers (frail: OR 1.6, 95% CI 1.3-2.0; prefrail: OR 1.4, 95% CI 1.2-1.5), had CCI ≥ 2 (frail: OR 5.1, 95% CI 2.1-12.6; prefrail: OR 2.1, 95% CI 1.2-3.8), and with low household income (frail: OR 4.0, 95% CI 2.8-5.8; prefrail: OR 2.7, 95% CI 2.2-3.3). This study revealed a significant association between PM2.5 exposure and frailty, with a stronger effect in vulnerable groups.


Subject(s)
Air Pollution/adverse effects , Frail Elderly , Frailty/epidemiology , Geriatric Assessment , Aged , Aged, 80 and over , Comorbidity , Female , Frailty/chemically induced , Frailty/physiopathology , Humans , Male , Particulate Matter/adverse effects , Risk Factors , Taiwan/epidemiology
5.
Biosensors (Basel) ; 10(8)2020 Aug 10.
Article in English | MEDLINE | ID: mdl-32785051

ABSTRACT

Urinary tract infections (UTI), one of the most common bacterial infections, annually affect 150 million people worldwide. Infants and the elderly are likely to have missed or delayed diagnosis of UTI due to difficulty clearly describing their symptoms. A rapid screening method for UTI is a critical and urgent need for these populations. The aim of our study is to develop a diaper-based testing device to assay urine biomarkers including pH, leukocyte, and nitrite level. This all-in-one device assists in urine collection and testing using a colorimetric approach to provide easily read visual results on the outside surface of a test strip-integrated diaper. In this study, we tested samples from 46 patients using testing strips and examined the results from 7 patients recruited to validate the strip-integrated diaper. In conclusion, this new diaper-based testing device is easy to use, rapid, and inexpensive, all of which imbue it with tremendous potential for development into a commercially viable UTI screening system.


Subject(s)
Absorbent Pads , Urinalysis/methods , Urinary Tract Infections/diagnosis , Bacterial Infections , Colorimetry , Female , Humans , Male , Nitrites/urine , Urinary Tract Infections/microbiology
6.
Pharmaceutics ; 11(9)2019 Sep 05.
Article in English | MEDLINE | ID: mdl-31491870

ABSTRACT

Although aerosol delivery through mechanical ventilators has been used to administer various medications, little is known of administration with colistin. This in vitro evaluation aimed to evaluate size distribution of colistin delivery by different types of nebulizers and concentrations during mechanical ventilation. Colistin methanesulfonate (colistin) for injection was dissolved in 6 mL of distilled water to produce a low concentration (L; 156 mg) and a high concentration (H; 312 mg). A dose volume of 6 mL was placed in a vibrating mesh nebulizer (VMN) and a jet nebulizer (JN). The inhaled mass (mean ± SD) of the VMN-L (53.80 ± 14.79 mg) was greater than both the JN-L (19.82 ± 3.34 mg, P = 0.001) and JN-H (31.72 ± 4.48 mg, P = 0.017). The nebulization time of the VMN-L (42.35 ± 2.30 min) was two times longer than the JN-L (21.12 ± 0.8 min) or JN-H (21.65 ± 0.42 min; P < 0.001). The mass median aerodynamic distal to the endotracheal tube was within a similar range at 2.03 to 2.26 µm (P = 0.434), independent of neb or formulation concentration. In conclusion, the VMN-L yields greater inhaled mass than the JN with either concentration. Therefore, a standard nominal dose of colistin results in a higher delivered dose during mechanical ventilation with a VMN compared with a JN and may be considered the preferred device. If JN must be used, multiple doses of low concentration colistin may compensate for poor delivery performance.

7.
Sci Rep ; 6: 36336, 2016 11 08.
Article in English | MEDLINE | ID: mdl-27824116

ABSTRACT

Discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase of collagen, is primarily expressed in epithelial cells. Activation of DDR1 stabilises E-cadherin located on the cell membrane; however, the detailed mechanism of DDR1-stabilised E-cadherin remains unclear. We performed DDR1 knockdown (Sh-DDR1) on Mardin-Darby canine kidney cells to investigate the mechanism of DDR1-stabilised E-cadherin. Sh-DDR1 decreased junctional localisation, increased endocytosis of E-cadherin, and increased physical interactions between E-cadherin and clathrin. Treatment of the dynamin inhibitor Dyngo 4a suppressed Sh-DDR1-induced E-cadherin endocytosis. In addition, the phosphorylation level of Src tyrosine 418 was increased in Sh-DDR1 cell junctions, and inhibition of Src activity decreased Sh-DDR1-induced E-cadherin endocytosis. To characterise the molecular mechanisms, blocking integrin ß1 decreased Src activity and E-cadherin junctional localisation in Sh-DDR1 cells. Photoconversion results showed that inhibition of Src activity rescued E-cadherin membrane stability and that inhibition of integrin ß1-Src signalling decreased stress fibres and rescued E-cadherin membrane stability in Sh-DDR1 cells. Taken together, DDR1 stabilised membrane localisation of E-cadherin by inhibiting the integrin ß1-Src-mediated clathrin-dependent endocytosis pathway.


Subject(s)
Cadherins/metabolism , Discoidin Domain Receptor 1/metabolism , Integrin beta1/metabolism , Proto-Oncogene Proteins pp60(c-src)/metabolism , Animals , Antigens, CD , Cadherins/chemistry , Cell Line , Cell Membrane/metabolism , Clathrin/metabolism , Discoidin Domain Receptor 1/genetics , Dogs , Endocytosis , Gene Knockdown Techniques , Humans , Intercellular Junctions/metabolism , Madin Darby Canine Kidney Cells , Protein Stability
8.
J Dermatol Sci ; 84(3): 248-257, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27756516

ABSTRACT

BACKGROUND: Epicutaneous immunization with allergens is an important sensitization route for atopic dermatitis. We recently showed in addition to the Th2 response following single epicutaneous immunization, a remarkable Th1 response is induced in B6 mice, but not in BALB/c mice, mimicking the immune response to allergens in human non-atopics and atopics. OBJECTIVE: We investigated the underlying mechanisms driving this differential Th1 response between BALB/c and B6 mice. METHODS: We characterized dermal dendritic cells by flow cytometric analysis. We measured the induced Th1/Th2 responses by measuring the IFN-γ/IL-13 contents of supernatants of antigen reactivation cultures of lymph node cells. RESULTS: We demonstrate that more dermal dendritic cells with higher activation status migrate into draining lymph nodes of B6 mice compared to BALB/c mice. Dermal dendritic cells of B6 mice have a greater ability to capture protein antigen than those of BALB/c mice. Moreover, increasing the activation status or amount of captured antigen in dermal dendritic cells induced a Th1 response in BALB/c mice. Further, differential activation behavior, but not antigen-capturing ability of dermal dendritic cells between BALB/c and B6 mice is dendritic cell-intrinsic. CONCLUSION: These results show that the differential activation behavior of dermal dendritic cells underlies the strain-specific Th1 responses following single epicutaneous immunization. Furthermore, our findings highlight the potential differences between human atopics and non-atopics and provide useful information for the prediction and prevention of atopic diseases.


Subject(s)
Antigens/administration & dosage , Dendritic Cells/immunology , Skin/cytology , Th1 Cells/immunology , Animals , Antigens/immunology , Cell Movement , Cytokines/metabolism , Dendritic Cells/cytology , Dermatitis, Atopic/immunology , Female , Flow Cytometry , Immunization , Interferon-gamma/metabolism , Langerhans Cells/immunology , Lymph Nodes/immunology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Species Specificity , Th1 Cells/cytology , Th2 Cells/cytology
9.
Front Behav Neurosci ; 10: 110, 2016.
Article in English | MEDLINE | ID: mdl-27375450

ABSTRACT

The developing brain is vulnerable to social defeat during the juvenile period. As complements of human studies, animal models of social defeat provide a straightforward approach to investigating the functional and neurobiological consequences of social defeats. Taking advantage of agonist behavior and social defeat in male golden hamster, a set of 6 experiments was conducted to investigate the consequences at multiple levels in young adulthood resulting from repeated, intermittent social defeats or "social threats" across the entire juvenile period. Male hamsters at postnatal day 28 (P28) were randomly assigned to either the social defeat, "social threat", or arena control group, and they correspondingly received a series of nine social interaction trials (i.e., either social defeat, "social threat", or arena control conditions) from P33 to P66. At the behavioral level (Experiment 1), we found that repeated social defeats (but not "social threats") significantly impacted locomotor activity in the familiar context and social interaction in the familiar/unfamiliar social contexts. At the physiological and hormonal levels (Experiments 2 and 3), repeated social defeat significantly enhanced the cortisol and norepinephrine concentrations in blood. Enlargement of the spleen was also found in the social defeat and "social threat" groups. At the immunological level (Experiment 4), the social defeat group showed lower levels of pro-inflammatory cytokines in the hypothalamus and hippocampus but higher concentration of IL-6 in the striatum compared to the other two groups. At the neurochemical level (Experiment 5), the socially defeated hamsters mainly displayed reductions of dopamine, dopamine metabolites, and 5-HT levels in the striatum and decreased level of 5-HT in the hippocampus. In Experiment 6, an increase in the spine density of hippocampal CA1 pyramidal neurons was specifically observed in the "social threat" group. Collectively, our findings indicate that repeated, intermittent social defeats throughout entire adolescence in hamsters impact their adult responses at multiple levels. Our results also suggest that the "social threat" group may serve as an appropriate control. This study further suggest that the alterations of behavioral responses and neurobiological functions in the body and brain might provide potential markers to measure the negative consequences of chronic social defeats.

11.
Oncotarget ; 6(25): 20946-58, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26189182

ABSTRACT

The stiffness sensing ability is required to respond to the stiffness of the matrix. Here we determined whether normal cells and cancer cells display distinct mechanical phenotypes. Cancer cells were softer than their normal counterparts, regardless of the type of cancer (breast, bladder, cervix, pancreas, or Ha-RasV12-transformed cells). When cultured on matrices of varying stiffness, low stiffness decreased proliferation in normal cells, while cancer cells and transformed cells lost this response. Thus, cancer cells undergo a change in their mechanical phenotype that includes cell softening and loss of stiffness sensing. Caveolin-1, which is suppressed in many tumor cells and in oncogene-transformed cells, regulates the mechanical phenotype. Caveolin-1-upregulated RhoA activity and Y397FAK phosphorylation directed actin cap formation, which was positively correlated with cell elasticity and stiffness sensing in fibroblasts. Ha-RasV12-induced transformation and changes in the mechanical phenotypes were reversed by re-expression of caveolin-1 and mimicked by the suppression of caveolin-1 in normal fibroblasts. This is the first study to describe this novel role for caveolin-1, linking mechanical phenotype to cell transformation. Furthermore, mechanical characteristics may serve as biomarkers for cell transformation.


Subject(s)
Caveolin 1/metabolism , Neoplasms/pathology , ras Proteins/metabolism , Actins/chemistry , Animals , Biomechanical Phenomena , Cell Proliferation , Cell Transformation, Neoplastic , Collagen/chemistry , Dogs , Elasticity , Enzyme Inhibitors/chemistry , Female , Fibroblasts/metabolism , Genes, ras , Humans , Madin Darby Canine Kidney Cells , Mice , Microscopy, Atomic Force , Microscopy, Confocal , Microscopy, Fluorescence , NIH 3T3 Cells , Neoplasms/metabolism , Phenotype , Phosphorylation , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/pathology , rhoA GTP-Binding Protein/metabolism
12.
Oncotarget ; 6(18): 15966-83, 2015 Jun 30.
Article in English | MEDLINE | ID: mdl-25965826

ABSTRACT

Modulations of cytoskeletal organization and focal adhesion turnover correlate to tumorigenesis and epithelial-mesenchymal transition (EMT), the latter process accompanied by the loss of epithelial markers and the gain of mesenchymal markers (e.g., vimentin). Clinical microarray results demonstrated that increased levels of vimentin mRNA after chemotherapy correlated to a poor prognosis of breast cancer patients. We hypothesized that vimentin mediated the reorganization of cytoskeletons to maintain the mechanical integrity in EMT cancer cells. By using knockdown strategy, the results showed reduced cell proliferation, impaired wound healing, loss of directional migration, and increased large membrane extension in MDA-MB 231 cells. Vimentin depletion also induced reorganization of cytoskeletons and reduced focal adhesions, which resulted in impaired mechanical strength because of reduced cell stiffness and contractile force. In addition, overexpressing vimentin in MCF7 cells increased cell stiffness, elevated cell motility and directional migration, reoriented microtubule polarity, and increased EMT phenotypes due to the increased ß1-integrin and the loss of junction protein E-cadherin. The EMT-related transcription factor slug was also mediated by vimentin. The current study demonstrated that vimentin serves as a regulator to maintain intracellular mechanical homeostasis by mediating cytoskeleton architecture and the balance of cell force generation in EMT cancer cells.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cytoskeleton/metabolism , Focal Adhesions/physiology , Vimentin/metabolism , Cell Adhesion/physiology , Cell Line, Tumor , Cell Movement/physiology , Cell Proliferation/physiology , Cytoskeleton/pathology , Epithelial-Mesenchymal Transition/physiology , Female , Gene Knockdown Techniques , Humans , MCF-7 Cells , Microtubules/metabolism , Microtubules/pathology , Vimentin/deficiency , Vimentin/genetics
13.
J Cell Mol Med ; 19(5): 934-47, 2015 May.
Article in English | MEDLINE | ID: mdl-25683605

ABSTRACT

Cancer metastasis occurs via a progress involving abnormal cell migration. Cell migration, a dynamic physical process, is controlled by the cytoskeletal system, which includes the dynamics of actin organization and cellular adhesive organelles, focal adhesions (FAs). However, it is not known whether the organization of actin cytoskeletal system has a regulatory role in the physiologically relevant aspects of cancer metastasis. In the present studies, it was found that lung adenocarcinoma cells isolated from the secondary lung cancer of the lymph nodes, H1299 cells, show specific dynamics in terms of the actin cytoskeleton and FAs. This results in a higher level of mobility and this is regulated by an immature FA component, ß-PIX (PAK-interacting exchange factor-ß). In H1299 cells, ß-PIX's activity was found not to be down-regulated by sequestration onto stress fibres, as the cells did not bundle actin filaments into stress fibres. Thus, ß-PIX mainly remained localized at FAs, which allowed maturation of nascent adhesions into focal complexes; this resulted in actin polymerization, increased actin network integrity, changes in the intracellular microrheology at the peripheral of the cell, and cell polarity, which in turn regulated cell migration. Perturbation of ß-PIX caused an inhibition of cell migration, including migration velocity, accumulated distance and directional persistence. Our results demonstrate the importance of ß-PIX to the regulation of high mobility of lung adenocarcinoma cell line H1299 and that this occurs via regulation of FA dynamics, changes in actin cytoskeleton organization and cell polarity.


Subject(s)
Actin Cytoskeleton/metabolism , Cell Movement , Cytoplasm/metabolism , Focal Adhesions/metabolism , Rho Guanine Nucleotide Exchange Factors/metabolism , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Cell Line, Tumor , Cell Polarity , Down-Regulation , Elasticity , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Microscopy, Confocal , Myosin Type II/metabolism , RNA Interference , Rho Guanine Nucleotide Exchange Factors/genetics , Stress Fibers/metabolism , Time-Lapse Imaging/methods , Viscosity
14.
Exp Dermatol ; 24(1): 67-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25363677

ABSTRACT

A murine repeated protein-patch model has been established to study epicutaneous sensitization in atopic dermatitis. This model has shown a predominant Th2 and a weak Th1 response in both BALB/c and C57BL/6 mice. However, Th responses induced in the repeated model are not consistent with the generally accepted theory that BALB/c and C57BL/6 mice are Th2 and Th1 prone and are representatives of human atopy and non-atopy, respectively. In this study, a single protein-patch model was established, which showed in addition to the Th2 response, a remarkable Th1 response in C57BL/6 mice, but not in BALB/c mice. Moreover, using muLangerin-DTR mice, we demonstrated that dermal dendritic cells, but not Langerhans cells, are critical in single epicutaneous sensitization in both strains of mice.


Subject(s)
Dendritic Cells/cytology , Langerhans Cells/cytology , Skin/immunology , Allergens/immunology , Animals , Antigens, CD/metabolism , Cell Movement , Cells, Cultured , Cytokines/immunology , Dermatitis, Atopic/immunology , Humans , Integrin alpha Chains/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Skin/pathology , Th1 Cells/cytology , Th2 Cells/cytology
15.
Biomed Mater Eng ; 24(6): 1959-67, 2014.
Article in English | MEDLINE | ID: mdl-25226892

ABSTRACT

The small intestinal submucosa (SIS) is an acellular collagen-based matrix, primarily composed of fibrillar collagens (types I, II, and V). They enhance healing due to a minimal immune response. A good degradation rate is the degradation of materials equal to the rate of remodeling in the host. The SIS should apply a good degradation rate and cytocompatibility. In this study, a series of SIS with different degradation rates is obtained by treatment with Ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). Morphology, composition, degradable ratio, mechanical properties and cytocompatibility of the SIS are evaluated. We determined a 20 µm thickness and 60 µm pore size of the native SIS. The degradable ratio of the native SIS was approximately 90% in the presence of 0.25 mg/ml collagenase for 24 hours. The storage modulus of the native SIS was 388 MPa. The degradable ratio of the SIS decreased to 6% and the storage modulus increased to 777 MPa after being treated with 30 mM EDC for 24 hours. In cytocompatibility assay, cell numbers on the native SIS were similar as on the treated SIS due to the non-toxicity of the EDC treatment process. This SIS exhibited collagenase resistance, stronger mechanical strength and good cytocompatibility after the EDC treatment concluded. The cross-linked SIS could be utilized as a potential cell carrier for tissue engineering application.


Subject(s)
Absorbable Implants , Carbodiimides/chemistry , Fibroblasts/cytology , Fibroblasts/physiology , Intestinal Mucosa/chemistry , Intestinal Mucosa/cytology , Tissue Scaffolds , Animals , Cell Adhesion , Cell Differentiation , Cell Line , Cell Movement , Cell Proliferation , Cross-Linking Reagents/chemistry , Equipment Failure Analysis , Materials Testing , Mice , Prosthesis Design , Rabbits , Swine , Tensile Strength
16.
J Cell Sci ; 127(Pt 19): 4186-200, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25107365

ABSTRACT

Focal adhesions (FAs) undergo maturation that culminates in size and composition changes that modulate adhesion, cytoskeleton remodeling and differentiation. Although it is well recognized that stimuli for osteogenesis of mesenchymal stem cells (MSCs) drive FA maturation, actin organization and stress fiber polarization, the extent to which FA-mediated signals regulated by the FA protein composition specifies MSC commitment remains largely unknown. Here, we demonstrate that, upon dexamethasone (osteogenic induction) treatment, guanine nucleotide exchange factor H1 (GEF-H1, also known as Rho guanine nucleotide exchange factor 2, encoded by ARHGEF2) is significantly enriched in FAs. Perturbation of GEF-H1 inhibits FA formation, anisotropic stress fiber orientation and MSC osteogenesis in an actomyosin-contractility-independent manner. To determine the role of GEF-H1 in MSC osteogenesis, we explore the GEF-H1-modulated FA proteome that reveals non-muscle myosin-II heavy chain-B (NMIIB, also known as myosin-10, encoded by MYH10) as a target of GEF-H1 in FAs. Inhibition of targeting NMIIB into FAs suppresses FA formation, stress fiber polarization, cell stiffness and osteogenic commitments in MSCs. Our data demonstrate a role for FA signaling in specifying MSC commitment.


Subject(s)
Focal Adhesions/metabolism , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Rho Guanine Nucleotide Exchange Factors/metabolism , Cell Differentiation/physiology , Cell Lineage , Humans , Osteogenesis , Signal Transduction
17.
Physiol Behav ; 128: 202-11, 2014 Apr 10.
Article in English | MEDLINE | ID: mdl-24530264

ABSTRACT

Social eavesdropping is a special type of social learning and it is defined as the act of extracting information from social interactions between conspecifics. Social eavesdropping has advantages in information gathering and has attracted increasing attention. Emerging studies on social eavesdropping have been reported in several species, but the lack of suitable and manipulable laboratory rodent models remains a challenge to the study of the underlying mechanisms of social eavesdropping. The aim of this study was to take advantage of golden hamsters and their agonistic behaviors to develop a new laboratory method to study social eavesdropping. Male hamsters with or without a defeat experience were used as bystanders and were exposed to either a fighting interaction or a neutral encounter between two male demonstrators in a social learning chamber for a 3-day social learning. The behavioral responses of the bystanders toward observed demonstrators were tested in a U-shaped maze before and after the 3-day social learning. We found that (1) bystanders were attracted to the winning demonstrators in both short-term and long-term tests in experiment 1; (2) bystanders with a brief defeat experience displayed the opposite behavioral pattern and avoided approaching the winning demonstrator in experiment 2. It is evident that these hamsters acquired information about the relative qualities and dominance of the demonstrators and behaved differently toward different conspecifics afterward. Collectively, male hamsters are capable of social eavesdropping and prior experience of defeat has a significant impact on their consequent behaviors. Our newly developed behavioral method offers several advantages and it is useful for the study of social eavesdropping and its underlying mechanisms.


Subject(s)
Mesocricetus/psychology , Social Behavior , Animals , Conflict, Psychological , Male
18.
J Biomed Sci ; 20: 1, 2013 Jan 03.
Article in English | MEDLINE | ID: mdl-23286586

ABSTRACT

BACKGROUND: Epicutaneous sensitization with protein allergen that induces predominant Th2 responses is an important sensitization route in atopic dermatitis. Fungal components have been shown to modulate Th cell differentiation. However, the effects of fungal components on epicutaneous sensitization are unclear. RESULTS: In this study, we showed that co-administration of curdlan, a dectin-1 agonist, during epicutaneous ovalbumin sensitization of BALB/c mice decreased the IL-5 and IL-13 levels in supernatants of lymph node cell ovalbumin reactivation cultures. Mechanistically, curdlan co-administration decreased IL-4 and IL-1ß expressions in draining lymph nodes. Curdlan co-administration also lower the migration of langerin+ CD103- epidermal Langerhans cells into draining lymph nodes at 96 hours post-sensitization which might be attributed to decreased expressions of IL-18 and IL-1ß in patched skin. Moreover, adoptive transfer of CFSE-labeled transgenic CD4 T cells confirmed that curdlan co-administration decreased the proliferation and IL-4-production of ovalbumin -specific T cells primed by epidermal Langerhans cells. CONCLUSIONS: These results indicated that concurrent exposure to a dectin-1 agonist suppresses the epicutaneously induced Th2 response by modulating the cytokine expression profiles in draining LNs and the migration of epidermal Langerhans cells. These results highlight the effects of fungal components on epicutaneous allergen sensitization in atopic diseases.


Subject(s)
Lectins, C-Type/immunology , Lymph Nodes/immunology , Ovalbumin/metabolism , Th2 Cells/immunology , beta-Glucans/administration & dosage , Administration, Cutaneous , Allergens/immunology , Allergens/metabolism , Animals , Antigens, Surface/metabolism , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cell Movement/immunology , Dermatitis, Atopic/metabolism , Dermatitis, Atopic/pathology , Interleukin-13/immunology , Interleukin-13/metabolism , Interleukin-5/immunology , Interleukin-5/metabolism , Lectins, C-Type/agonists , Lectins, C-Type/metabolism , Lymph Nodes/metabolism , Mannose-Binding Lectins/metabolism , Mice , Mice, Inbred BALB C , Th2 Cells/cytology , Th2 Cells/metabolism
19.
Arch Gerontol Geriatr ; 54(3): e290-3, 2012.
Article in English | MEDLINE | ID: mdl-22209536

ABSTRACT

Post-acute care (PAC) is of great importance to promote functional recovery of older patients, which should be provided by the interdisciplinary team. In PAC services, rehabilitative therapy plays a key role, but the optimal intensity for rehabilitative therapy remained unclear. Between July 2007 and December 2010, all patients with functional decline after acute illness hospitalization admitted to the PAC unit of a community hospital in Taiwan were enrolled. Usual rehabilitation program, 40-min per day and five days a week, was provided to all patients before April 2009. After April 2009, the rehabilitative therapy was increased to 80min per day. Functional improvement was measured by comprehensive geriatric assessment (CGA) at admission and 4 weeks after admissions to the PAC unit. Overall, 458 patients (mean age: 83.4±5.5 years, all males) completed PAC services. Compared of all dimensions in CGA, increased dosage of rehabilitative therapy showed significantly better improvement in daily living activities (Barthel index (BI): 28.8±18.4 vs. 20.0±14.6, p<0.001), depressive mood (geriatric depression score short form (GDS): -0.5±1.0 vs. -0.1±0.5, p<0.001), and pain reduction (numerical rating scale (NRS): -2.0±2.2 vs. -0.9±2.1, p=0.01); but not in cognitive function (mini-mental status examination (MMSE): 2.9±3.3 vs. 3.3.±5.2, p=0.305), and nutritional status (body mass index (BMI): 0.3±0.9 vs. 0.3±2.5, p=0.9). In conclusion, intensive rehabilitative therapy significantly promote physical and psychological function with pain reduction, which deserves further investigations to evaluate whether there is a ceiling effect of rehabilitative therapy in PAC services.


Subject(s)
Recovery of Function , Rehabilitation/methods , Activities of Daily Living , Aged , Aged, 80 and over , Body Mass Index , Cognition Disorders/rehabilitation , Depression/rehabilitation , Geriatric Assessment , Hospitalization , Humans , Male , Nutritional Status , Pain/rehabilitation , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL
...