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1.
Biochem Biophys Res Commun ; 704: 149699, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38412668

RESUMEN

With an increasing understanding of the mechanisms of fracture healing, it has been found that nerve injury plays a crucial role in the process, but the specific mechanism is yet to be completely revealed. To address this issue and provide novel insights for fracture treatment, we compiled this review. This review aims to study the impact of nerve injury on fracture healing, exploring the role of neurotrophic factors in the healing process. We first revisited the effects of the central nervous system (CNS) and the peripheral nervous system (PNS) on the skeletal system, and further explained the phenomenon of significantly accelerated fracture healing under nerve injury conditions. Then, from the perspective of neurotrophic factors, we delved into the physiological functions and mechanisms of neurotrophic factors, such as nerve growth factor (NGF), Neuropeptides (NPs), and Brain-derived neurotrophic factor (BDNF), in bone metabolism. These effects include direct actions on bone cells, improvement of local blood supply, regulation of bone growth factors, control of cellular signaling pathways, promotion of callus formation and bone regeneration, and synergistic or antagonistic effects with other endocrine factors, such as Sema3A and Transforming Growth Factor ß (TGF-ß). Finally, we discussed the treatments of fractures with nerve injuries and the future research directions in this review, suggesting that the relationship between nerve injury and fracture healing, as well as the role of nerve injury in other skeletal diseases.


Asunto(s)
Fracturas Óseas , Neuropéptidos , Enfermedades del Sistema Nervioso Periférico , Humanos , Curación de Fractura/fisiología , Regeneración Ósea/fisiología
2.
Opt Lett ; 48(6): 1367-1370, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36946929

RESUMEN

With the increasing signal rates of a long-haul backbone dense-wavelength-division-multiplexing (DWDM) transmission system, e.g., from 100 Gb/s to 400 Gb/s and even to 800 Gb/s, optical path impairments simultaneously become more severe. Harmful factors being formerly insignificant become noticeable, e.g., nonlinear phase noise (NPN) on main DWDM channels induced by the cross-phase modulation (XPM) from the low-speed optical supervisory channel (OSC). Field trials show that a greater than 5.13-dB penalty can be observed on the shortest channel of 400G DP-16QAM-PCS over G.654.E links, which greatly degrades the overall transmission performance and limits the maximum reach. In this paper, we propose a dual-OSC structure with opposite signals to compensate for performance degradation caused by OSC-induced NPN. This method involves no extra digital signal processing (DSP), which is not only simple but also applicable for universal signal rates. By experimental demonstration, a 1.32-dB gain in Q (dB) for 200G DP-16QAM transmission over 1618-km G.652.D can be done, almost achieving the same performance as the no OSC case.

3.
Opt Express ; 30(4): 5868-5878, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209540

RESUMEN

Mode-division multiplexing (MDM) technique based on few-mode fibers (FMFs) can achieve multiplicative growth in single-fiber capacity by using different linearly polarized (LP) modes or mode groups as spatial channels. However, its deployment is seriously impeded because multiple-input multiple-output digital signal processing (MIMO-DSP) with huge computational load must be adopted to combat intermodal crosstalk for long-haul FMF transmission. In this paper, we present an intermodal-MIMO-free MDM transmission scheme based on weakly coupled multiple-ring-core FMF, which achieves ultralow distributed modal crosstalk (DMC) so that the signal in each LP mode can be independently received by single-LP-mode MIMO-DSP even after hundreds-of-kilometer transmission. Evaluation method for the required DMC levels is proposed and different transmission reaches are investigated by simulation. By adopting an improved method for quantitative DMC measurement, we show that the required DMC level for long-haul transmission is feasible. Finally, we experimentally demonstrate 1800-km LP01/LP02 multiplexed transmission and 525-km LP01/LP21/LP02 multiplexed transmission only adopting 2×2 or 4×4 MIMO-DSP. The proposed scheme may pave the way to practical applications of long-haul MDM techniques for the first time.

4.
Opt Express ; 28(9): 12558-12565, 2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32403751

RESUMEN

Quantum key distribution (QKD) is one of the most practical applications in quantum information processing, which can generate information-theoretical secure keys between remote parties. With the help of the wavelength-division multiplexing technique, QKD has been integrated with the classical optical communication networks. The wavelength-division multiplexing can be further improved by the mode-wavelength dual multiplexing technique with few-mode fiber (FMF), which has additional modal isolation and large effective core area of mode, and particularly is practical in fabrication and splicing technology compared with the multi-core fiber. Here, we present for the first time a QKD implementation coexisting with classical optical communication over weakly-coupled FMF using all-fiber mode-selective couplers. The co-propagation of QKD with one 100 Gbps classical data channel at -2.60 dBm launched power is achieved over 86 km FMF with 1.3 kbps real-time secure key generation. Compared with single-mode fiber using wavelength-division multiplexing, given the same fiber-input power, the Raman noise in FMF using the mode-wavelength dual multiplexing is reduced by 86% in average. Our work implements an important approach to the integration between QKD and classical optical communication and previews the compatibility of quantum communications with the next-generation mode division multiplexing networks.

5.
Brain Behav Immun ; 87: 531-542, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32014577

RESUMEN

Spinal cord injury (SCI) is a destructive polyneuropathy that can result in loss of sensorimotor function and sphincter dysfunction, and even death in critical situations. MicroRNAs (miRs) are a series of non-coding RNA molecules that are involved in transcriptional regulation. Previous studies have demonstrated that modulation of multiple miRs is involved in neurological recovery after SCI. However, the functions of miR-340-5p in SCI remain uncertain. Therefore, we probed the therapeutic effect and mechanism of miR-340-5p in microglia in vitro and in vivo in SCI rats. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were employed to examine the alterations in miR-340-5p and P38 levels in SCI rats. miR-340-5p targets in microglia were ascertained using luciferase reporter assays, immunofluorescence analyses, and western blotting. We also established an SCI model and administered miR-340-5p. The effects of miR-340-5p on the amelioration of inflammation, oxidative stress, and apoptosis following SCI were assessed using immunofluorescence, immunohistochemistry, and histological analyses. Finally, locomotor function recovery was determined using the Basso, Beattie, Bresnahan rating scale. In our study, the expression profiles and luciferase assay results clarified that P38 was a target of miR-340-5p, which was associated with activation of the P38-MAPK signaling pathway. Elevation of miR-340-5p decreased P38 expression, subsequently inhibiting the inflammatory reaction. SCI-induced secondary neuroinflammation was relieved under miR-340-5p treatment. Moreover, by controlling neuroinflammation, the increased levels of miR-340-5p might counter oxidative stress and reduce the degree of apoptosis. We also observed decreasing gliosis and glial scar formation and increasing neurotrophin expression at the chronic stage of SCI. Together, these potential effects of miR-340-5p treatment ultimately improved locomotor function recovery in SCI rats.


Asunto(s)
MicroARNs , Traumatismos de la Médula Espinal , Animales , Apoptosis , Modelos Animales de Enfermedad , MicroARNs/genética , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Médula Espinal , Traumatismos de la Médula Espinal/complicaciones
6.
Opt Express ; 27(26): 38281-38288, 2019 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-31878598

RESUMEN

Multiple-input-multiple-output digital signal processing (DSP) has become a severe bottleneck for mode division multiplexing (MDM) because of its huge computational complexity. In this paper, we propose a novel scheme for real-time DSP-free intensity-modulation/direct-detection (IM/DD) MDM transmission, in which the transmission few-mode fiber (FMF) is characterized by multiple-ring-core structure to suppress modal crosstalk among each LP mode, while each pair of non-circularly-symmetric degenerate modes is simultaneously demultiplexed by a degenerate-mode-selective fiber coupler for DSP-free reception. Based on a 10 km ultralow-modal-crosstalk double-ring-core FMF and a pair of all-fiber 4-LP-mode MUX/DEMUX, we demonstrate the first IM/DD MDM prototype system using commercial single-mode (SM) 10 Gbps SFP + modules and 4K video transceivers without any hardware modifications. The temperature and wavelength dependence are evaluated. The stable Q2-factor performance proves that it can be a smooth evolution scheme from conventional SM IM/DD systems. Moreover, the scheme can be further extended to support more modes with improved FMF design adopting more ring areas.

7.
Opt Express ; 27(11): 16271-16280, 2019 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-31163807

RESUMEN

Spatial division multiplexing transmission over few-mode multicore fiber (FM-MCF) recently attracts great interests by simultaneously exploiting two more dimensions than conventional single mode fibers. In this paper, we propose an all-fiber spatial multiplexer (MUX) by cascading mode-selective fiber couplers (MSCs) with a fiber-bundle-type fan-in device, and spatial demultiplexer (DEMUX) by cascading a fiber-bundle-type fan-out device with degenerate-mode-selective fiber couplers and MSCs. Thanks to the low crosstalk of the FM-MCF, spatial MUX/DEMUX and their coupling, weakly-coupled 7-core-2-LP-mode real-time transmission over 1-km of FM-MCF is successfully demonstrated using 10-Gbps commercial enhanced small form-factor pluggable (SFP + ) transceivers.

8.
Opt Lett ; 44(9): 2145-2148, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31042169

RESUMEN

Three types of hollow-core fibers, i.e., photonic-bandgap fiber, negative-curvature fiber, and conjoined-tube fiber, are compared in terms of data transmission performance. Their group velocity dispersions and group indices are measured in detail by using low-coherence interferometry. Whilst all three fibers show good performance with an optimized central launch, they behave differently under offset launch for 10 Gbit/s on-off keying transmission. We use a Q2-factor analysis method to gain insight into the data transmission over a hollow-core fiber. The low-loss, low-intermodal crosstalk conjoined-tube fiber shows great resilience to bending and offset launch compared to the other two hollow-core fibers, enabling genuine penalty-free data transmission in realistic environments.

9.
Cell Physiol Biochem ; 51(4): 1921-1931, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30513512

RESUMEN

BACKGROUND/AIMS: To explore the potential role of miR-544a in spinal cord injury and the possible mechanism involved. METHODS: We established a mouse model with spinal cord injury to examine the changes in grip force recovery of the forelimb or the posterior limb of the mouse. Microarray was performed to achieve differentiated miRNAs in the mice. The expressions of miR-544a, MCP-1, IL36B and IL17B after spinal cord injury were detected by qRT-PCR. Subsequently, miR-544a was overexpressed to observe changes in inflammation and grip strength after spinal cord injury. Target gene of miR-544a was then predicted using bioinformatics technology. Finally, dual luciferase reporter gene assay was used to verify the binding of miR-544a to its target gene. RESULTS: Using mice models with spinal cord injury, we found that the strength of their four limbs began to recover 7 days after injury. The results of microarray and qRT-PCR confirmed that mir-544a level in mice with spinal cord injury decreased with increase of injury time, while the levels of inflammatory genes MCP-1 (monocyte chemoattractant protein-1), IL1 (interleukin-1) and TNF-α (tumor necrosis factor alpha) IL36B (interleukin-36 beta) and IL17B (interleukin-17 beta) were significantly increased. However, overexpression of miR-544a in the mice significantly reduced the level of inflammation and restored their grip strength in their four limbs. Finally, we found that miR-544a can bind to the NEUROD4 (Neurogenic differentiation 4) 3'UTR (Untranslated Region) region through bioinformatics website prediction, which was further confirmed by dual luciferase reporter assay. NEUROD4 level was significantly reduced following the overexpression of miR-544a. CONCLUSION: The expression of miR-544a was significantly decreased after spinal cord injury. High expression of miR-544a could alleviate the inflammation caused by spinal cord injury and promote the recovery of spinal cord via the inhibition of NEUROD4.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Regulación hacia Abajo , Inflamación/genética , MicroARNs/genética , Proteínas del Tejido Nervioso/genética , Traumatismos de la Médula Espinal/genética , Regiones no Traducidas 3' , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Femenino , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , MicroARNs/inmunología , Proteínas del Tejido Nervioso/inmunología , Médula Espinal/inmunología , Médula Espinal/patología , Traumatismos de la Médula Espinal/inmunología , Traumatismos de la Médula Espinal/patología , Regulación hacia Arriba
10.
Biochem Biophys Res Commun ; 502(4): 493-500, 2018 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-29859193

RESUMEN

Osteosarcoma (OS) is the most common malignant bone tumor in children and adolescents. LncRNA has been confirmed to participate in a variety of cancers. The purpose of this study was to explore the effect of FOXP4-AS1 on the development of osteosarcoma (OS) and its underlying mechanism. FOXP4-AS1 expressions in 60 OS tissues and paracancerous tissues were detected by qRT-PCR (quantitative real-time polymerase chain reaction). We confirmed that FOXP4-AS1 was overexpressed in OS tissues than that of paracancerous tissues. The disease-free survival and overall survival of OS patients were not correlated with age, gender and tumor location, but remarkably correlated with FOXP4-AS1 expression, tumor size and lung metastasis. For in vitro experiments, MG63 cells expressed a higher expression of FOXP4-AS1, whereas U2OS cells expressed a lower expression, which were selected for the following studies. Overexpressed FOXP4-AS1 led to enhanced proliferation, migration and invasion, shortened G0/G1 phase, as well as inhibited cell cycle. Knockdown of FOXP4-AS1 in MG63 cells obtained the opposite results. Furthermore, RIP assay indicated that FOXP4-AS1 could inhibit LATS1 expression by binding to LSD1 and EZH2, so as to participate in OS development. In conclusion, these results revealed that FOXP4-AS1 is overexpressed in OS, and is the independent risk factor in OS prognosis. Upregulated FOXP4-AS1 promotes the proliferation, migration and cell cycle, but inhibits apoptosis of OS cells. Furthermore, FOXP4-AS1 participates in the development and progression of OS by downregulating LATS1 via binding to LSD1 and EZH2.


Asunto(s)
Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Histona Demetilasas/metabolismo , Osteosarcoma/genética , Osteosarcoma/metabolismo , Proteínas Serina-Treonina Quinasas/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Adolescente , Adulto , Neoplasias Óseas/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Regulación hacia Abajo , Femenino , Humanos , Masculino , Osteosarcoma/patología , Fosfohidrolasa PTEN/genética , Unión Proteica , Adulto Joven
11.
Opt Express ; 26(7): 8356-8363, 2018 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-29715803

RESUMEN

Weakly coupled-mode division multiplexing (MDM) over few-mode fibers (FMF) for short-reach transmission has attracted great interest, which can avoid multiple-input-multiple-output digital signal processing (MIMO-DSP) by greatly suppressing modal crosstalk. In this paper, step-index FMF supporting 4 linearity polarization (LP) modes for MIMO-free transmission is designed and fabricated for the first time, to our knowledge. Modal crosstalk of the fiber is suppressed by increasing the mode effective refractive index differences. The same fabrication method as standard single-mode fiber is adopted so that it is practical and cost-effective. The mode multiplexer/demultiplexer (MUX/DEMUX) consists of cascaded mode-selective couplers (MSCs), which are designed and fabricated by tapering the proposed FMF with single-mode fiber (SMF). The mode MUX and DEMUX achieve very low modal crosstalk not only for the multiplexing/demultiplexing but also for the coupling to/from the FMF. Based on the fabricated FMF and mode MUX/DEMUX, we successfully demonstrate the first simultaneous 4-modes (LP01, LP11, LP21 & LP31) 10-km FMF transmission with 10-Gb/s intensity modulation and MIMO-free direct detection (IM/DD). The modal crosstalk of the whole transmission link is successfully suppressed to less than -16.5 dB. The experimental results indicate that FMF with simple step-index structure supporting 4 weakly-coupled modes is feasible.

12.
Cell Physiol Biochem ; 42(6): 2207-2219, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28817807

RESUMEN

BACKGROUND/AIMS: Cardiac fibrosis after myocardial infarction (MI) has been identified as an important factor in the deterioration of heart function. Previous studies have demonstrated that miR-21 plays an important role in various pathophysiological processes in the heart. However, the role of miR-21 in fibrosis regulation after MI remains unclear. METHODS: To induce cardiac infarction, the left anterior descending coronary artery was permanently ligated of mice. First, we explored the expression of miR-21 in the infarcted zone in mice model of MI via RT-qPCR. Next, we examined the effects of TGF-ß1 on miR-21 expression in cardiac fibroblasts (CFs). Then, CFs were infected with miR-21 mimics or miR-21 inhibitors to investigate the effects of miR-21 on the process of CFs activation in vitro. Further, bioinformatics analysis and luciferase reporter assay were performed to identify and validate the target gene of miR-21. At last, in-vivo study was done to confirm MiR-21 regulated myocardial fibrosis after MI in mice. RESULTS: MiR-21 was up-regulated in the infarcted zone after MI in vivo. TGF-ß1 treatment increased miR-21 expression in CFs. Overexpression of miR-21 promoted the effects of TGF-ß1-induced activation of CFs, evidenced by increased expression of Col-1, α-SMA and F-actin, whereas inhibition of miR-21 attenuated the process of fibrosis. Bioinformatics, Western blot analysis and luciferase reporter assay demonstrated that Smad7 is a direct target of miR-21. In addition, in-vivo study revealed that MiR-21 regulated myocardial fibrosis after MI in mice. CONCLUSION: These findings suggested that miR-21 has a critical role in CF activation and cardiac fibrosis after MI through via TGF-ß/Smad7 signaling pathway. Thus, miR-21 promises to be a potential therapy in treatment of cardiac fibrosis after MI.


Asunto(s)
MicroARNs/metabolismo , Proteína smad7/metabolismo , Animales , Antagomirs/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibrosis , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Miocardio/citología , Miocardio/metabolismo , Interferencia de ARN , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Proteína smad7/antagonistas & inhibidores , Proteína smad7/genética , Factor de Crecimiento Transformador beta1/farmacología , Regulación hacia Arriba/efectos de los fármacos
13.
Cell Physiol Biochem ; 38(2): 809-20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26872365

RESUMEN

BACKGROUND/AIMS: Postmenopausal osteoporosis is closely associated with reduction in the differentiation of mesenchymal stem cells (MSCs) into osteoblasts. Previous studies have demonstrated that miR-214 plays an important role in the genesis and development of postmenopausal osteoporosis. Here, we performed this study to investigate the potential mechanism by which miR-214 regulates osteoblast differentiation of MSCs. METHODS: First, we explored the expression of miR-214 in MSCs of osteoporotic mice. Next, we examined the change of miR-214 during osteoblast differentiation of MSCs. Then, MSCs were infected with lentiviral vectors expressing miR-214 or miR-214 sponge to investigate the effect of miR-214 on osteoblast differentiation of MSCs. Further, bioinformatics analysis and luciferase reporter assay were performed to identify and validate the target gene of miR-214. RESULTS: MiR-214 was up-regulated in MSCs of osteoporotic mice and down-regulated during osteoblast differentiation of MSCs. Furthermore, overexpression of miR-214 inhibited osteoblast differentiation of MSCs in vitro, whereas inhibition of miR-214 function promoted this process, evidenced by increased expression of osteoblast-specific genes, alkaline phosphatase (ALP) activity, and matrix mineralization. Bioinformatics, Western blot analysis and luciferase reporter assay demonstrated that FGFR1 is a direct target of miR-214. CONCLUSIONS: MiR-214 attenuates osteogenesis by inhibiting the FGFR1/FGF signaling pathway. Our findings suggest that targeting miR-214 promises to be a potential therapy in treatment of postmenopausal osteoporosis.


Asunto(s)
Regulación de la Expresión Génica , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteoblastos/citología , Osteoporosis Posmenopáusica/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Animales , Diferenciación Celular , Células Cultivadas , Regulación hacia Abajo , Femenino , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Ratones , Ratones Endogámicos C57BL , Osteoblastos/metabolismo , Osteoblastos/patología , Osteogénesis , Osteoporosis Posmenopáusica/fisiopatología , Regulación hacia Arriba
14.
Cell Physiol Biochem ; 38(6): 2261-71, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27188306

RESUMEN

BACKGROUND/AIMS: Epidural fibrosis, a common complication after laminectomy, has been demonstrated to be closely associated with poor surgical outcomes. Previous studies showed that taurine had remarkable anti-fibrotic effects on lung and liver fibrosis. We performed this study to investigate the effects of taurine in rat models of epidural fibrosis after laminectomy and to explore the potential molecular mechanism. METHODS: Laminectomy was performed on each rat to establish epidural fibrosis model. After taurine treatment, Masson's trichrome and immunohistochemistry staining were used to examine epidural fibrosis. Cell viability was determined using the Cell Counting Kit-8 assay. Annexin V/Propidium Iodide double staining was performed to detect fibroblasts apoptosis. Microarray was adopted to identify significantly changed mRNAs. mRNA expression was measured by qRT-PCR. Lentivirus infection was performed to establish stable knockdown and overexpression cell lines. The expression of fibrosis-related proteins was determined via Western blot. RESULTS: Taurine treatment markedly reduced laminectomy-induced epidural fibrosis in rat models. However, this effect of taurine was independent on TGF-ß/Smad pathway, evidenced by no change in the expression of TGF-ß and its receptors. Besides, taurine had almost no effect on cell apoptosis. Interestingly, taurine treatment significantly decreased expression of EGR1 (Early growth response protein 1), an enhancer of fibrosis, both in vivo and in vitro. Furthermore, overexpression of EGR1 increased activation of fibroblasts, while EGR1 knockdown achieved an opposite effect, indicating that EGR1 plays a key role in the inhibitory effect of taurine on TGF-ß-induced fibrosis. CONCLUSIONS: Reduced epidural fibrosis in vivo and decreased activation of fibroblasts in vitro after taurine treatment was mediated by EGR1. Taurine promises to be a potential prevention for epidural fibrosis after laminectomy.


Asunto(s)
Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Espacio Epidural/efectos de los fármacos , Espacio Epidural/patología , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Taurina/uso terapéutico , Animales , Células Cultivadas , Regulación hacia Abajo , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Espacio Epidural/citología , Espacio Epidural/metabolismo , Fibrosis , Laminectomía , Masculino , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta1/metabolismo
15.
Cell Physiol Biochem ; 39(5): 1965-1976, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27771715

RESUMEN

BACKGROUND/AIMS: Hypertrophic scars (HS) formation results from reduced apoptosis and increased proliferation of fibroblasts. Therefore, apoptosis of fibroblasts is a key target for the development of novel therapeutic strategies for HS. Previous reports demonstrated that FK506 could attenuate scar formation in vivo and FK506 could also induce endoplasmic reticulum stress (ER stress). However, the effects of FK506 on ER stress-mediated apoptosis in fibroblasts remain unclear. METHODS: Rat skin fibroblasts were used in the study. Cell viability was examined using cell counting Kit-8. Apoptosis was detected by Annexin V/Propidium Iodide Double Staining. Gene silencing was performed using Small Interfering RNAs (siRNAs) or via lentiviral infection. The expression of apoptosis-related proteins was determined via Western blot. Interaction between proteins was explored by co-immunoprecipitation. RESULTS: FK506 significantly reduced cell viability and induced apoptosis in fibroblasts. Interestingly, ER stress was also activated after FK506 treatment. We further demonstrated that FK506-induced apoptosis was mediated by ER stress via activating CHOP, evidenced by decreased apoptosis after inhibition of ER stress using TUDCA or silencing expression of CHOP. Furthermore, Co-immunoprecipitation results indicated that treatment of FK506 induced disassociation of FKBP12.6 from RyR2 and its translocation from ER membrane to cytosol, consequently promoting ER stress-mediated apoptosis. CONCLUSION: FK506-induced fibroblasts apoptosis was mediated by ER stress via CHOP signaling pathway.


Asunto(s)
Inhibidores de la Calcineurina/farmacología , Estrés del Retículo Endoplásmico/genética , Fibroblastos/metabolismo , Proteínas de Unión a Tacrolimus/genética , Tacrolimus/farmacología , Factor de Transcripción CHOP/genética , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Apoptosis/genética , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Regulación de la Expresión Génica , Cultivo Primario de Células , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Transducción de Señal , Proteínas de Unión a Tacrolimus/metabolismo , Factor de Transcripción CHOP/antagonistas & inhibidores , Factor de Transcripción CHOP/metabolismo
16.
Opt Express ; 24(19): 21609-18, 2016 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-27661899

RESUMEN

Mode division multiplexing (MDM) has been widely investigated in optical transmission systems and networks to improve network capacity. However, the MDM receiver is always expensive and complex because coherent detection and multiplex-input-and-multiplex-output (MIMO) digital signal processing (DSP) are required to demultiplex each spatial mode. In this paper, we investigate the application of MDM in short-reach scenarios such as datacenter networking. Two-dimensional MDM and wavelength division multiplexing node structure based on low modal-crosstalk few-mode fiber (FMF) and components is proposed, in which signal in each mode or wavelength can be independently switched. We experimentally demonstrate independent adding, dropping and switching functionalities with two linearly polarized modes and four wavelength channels over a total 11.8-km 2-mode low modal-crosstalk FMFs. The structure is simple without coherent detection or MIMO DSP. Only slight penalties of receiver sensitivity are observed for all switching operations. The influence of modal-crosstalk accumulation for cascaded switching nodes is also investigated.

17.
Opt Express ; 24(20): 22413-22422, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27828313

RESUMEN

In this paper, we propose a cost-effective wavelength-reused mode-division-multiplexing (MDM) system for high speed symmetrical bidirectional mobile fronthaul application. At the base band unit (BBU) pool, one of the spatial modes is used to transmit signal carrier while the others are used for downstream (DS) signal channels. At the remote radio unit (RRU) side, the signal carrier is split and reused as modulation carrier for all the upstream (US) signal channels after mode demultiplexing. Thanks to the low mode crosstalk characteristic of the mode multiplexer/demultiplexer (MUX/DEMUX) and few-mode fiber (FMF), the signal carrier and each signal channel can be effectively separated. The spectral efficiency (SE) is significantly enhanced when multiple spatial channels are used. Compared with other wavelength reused scheme in which the downstream and upstream be modulated in orthogonal dimension, the modulation format of both directions are independent in the proposed wavelength reused MDM system. Therefore, it can easily achieve symmetrical bidirectional transmission without residual re-modulation crosstalk. The proposed scheme is scalable to multi-wavelength application when wavelength MUX/DEMUX is utilized. With the proposed scheme, we demonstrate a proof of concept intensity modulated 4 × 25-Gb/s 16-QAM orthogonal frequency division multiplexing (OFDM) transmission over 10-km FMF using low modal-crosstalk two-mode FMF and MUX/DEMUX with error free operation. The downstream receiver sensitivity is -21 dBm while the upstream receiver sensitivity is -18 dBm for bidirectional transmission. Due to the Rayleigh backscattering and other spurious reflections, the upstream suffers 2 dB power penalty compared with unidirectional transmission without downstream. To mitigate bidirectional transmission impairments, we propose a simple and effective method to suppress Rayleigh backscattering by shifting the downstream subcarrier frequency. A receiver sensitivity improvement of up to 2.5 dB is achieved for upstream with different downstream power.

18.
Med Sci Monit ; 22: 4062-4065, 2016 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-27794162

RESUMEN

BACKGROUND Gremlin-1, a bone morphogenetic protein (BMP) antagonist, is up-regulated in osteoarthritis (OA). Therefore, we aim to evaluate the correlation between gremlin-1 concentrations and the onset and severity of OA. MATERIAL AND METHODS We performed this cross-sectional study in a population of 212 patients with knee OA and 125 healthy controls. RESULTS Patients with knee OA had higher serum gremlin-1 concentrations than healthy controls. Serum and synovial fluid (SF) gremlin-1 concentrations increased according to advanced Kellgren-Lawrence grading stages. CONCLUSIONS Serum and SF gremlin-1 concentrations are correlated with the onset and severity of knee OA.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/metabolismo , Osteoartritis de la Rodilla/metabolismo , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/sangre , Péptidos y Proteínas de Señalización Intercelular/genética , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/sangre , Osteoartritis de la Rodilla/genética , Índice de Severidad de la Enfermedad , Líquido Sinovial/metabolismo , Regulación hacia Arriba
19.
Cell Physiol Biochem ; 37(6): 2171-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26605538

RESUMEN

BACKGROUND/AIMS: Schwann cells (SCs) which were demonstrated to be responsible for axonal myelination and ensheathing are widely studied and commonly used for cell transplantation to treat spinal cord injury (SCI). We performed this meta-analysis to summarize the effects of SCs versus controls for locomotor recovery in rat models of traumatic SCI. METHODS: Studies of the BBB scores after transplantation of SCs were searched out from Pubmed, Cochrane Library Medline databases and analyzed by Review Manager 5.2.5. RESULTS: Thirteen randomized controlled animal trials were selected with 283 rats enrolled. The studies were divided to different subgroups by different models of SCI, different cell doses for transplantation, different sources of SCs and different transplantation ways. The pooled results of this meta-analysis suggested that SCs transplantation cannot significantly improve the locomotor recovery at a short time after intervention (1 week after transplantation) in both impacted and hemi-sected SCI models. However, at a longer time after intervention (3, 5-7 and over 8 weeks after transplantation), significant improvement of BBB score emerged in SCs groups compared with control groups. Subgroup analyses revealed that SCs transplantation can significantly promote locomotor recovery regardless of in high or low doses of cells, from different sources (isolated from sciatic nerves or differentiated from bone marrow stromal cells(BMSCs)) and with or without scaffolding. CONCLUSION: SCs seem to demonstrate substantial beneficial effects on locomotor recovery in a widely-used animal models of SCI.


Asunto(s)
Trasplante de Células , Locomoción , Células de Schwann/trasplante , Traumatismos de la Médula Espinal/terapia , Animales , Ratas , Traumatismos de la Médula Espinal/fisiopatología
20.
Opt Express ; 23(16): 20495-504, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26367902

RESUMEN

Elastic optical networks (EON) based on optical superchannel enables higher spectral flexibility, in which the network nodes should provide multiple all-optical functionalities to manipulate bandwidth-variable data traffic. In this paper, we propose and demonstrate an EON node structure supporting reconfigurable optical superchannel multicasting. The node structure incorporates a shared multicasting module, which performs reconfigurable selection of target incoming/outgoing superchannels/replicas and leverages a group of nonlinear devices to satisfy multiple multicast requests. Moreover, an optical comb is utilized to efficiently provide and manage all pump resources for multicasting with potential cost reduction and phase noise inhibition. Based on the node structure, we experimentally demonstrate polarization division multiplexing (PDM) superchannel multicasting scenarios with different replica amount, input/output locations, and modulation formats. Less than 0.7 dB optical signal-to-noise ratio (OSNR) penalties are demonstrated in multiple multicasting scenarios.

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