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Dupuytren disease (DD) is a progressive fibrous proliferative disease. It invades the palmar aponeurosis and extends to the finger fascia, eventually leading to flexion contracture of the metacarpophalangeal or interphalangeal joint. At present, surgical resection and the local injection of collagenase are the main methods for the treatment of DD, but postoperative complications and high recurrence rates often occur. Bioinformatics analysis showed that the increased expression of SFRP4 protein was closely related to the incidence of DD. Persistent and effective inhibition of SFRP4 expression may be a promising treatment for DD. We prepared SFRP4 siRNA/nanoparticle complexes (si-SFRP4) and negative siRNA/nanoparticle complexes (NC) and applied them in vitro and in vivo. Flow cytometry analysis showed that si-SFRP4 could be successfully transfected into DD cells. MTT and EdU staining assays showed that the OD values and percentage of EdU-positive cells in the si-SFRP4 group were significantly lower than those in the NC group. Scratch tests showed that the wound healing rate of the si-SFRP4 group was lower than that of the NC group, and the difference was statistically significant. The expression of SFRP4 and α-SMA protein in the si-SFRP4 group significantly decreased in both DD cells and xenografts. Compared with the NC group, the xenograft quality of the si-SFRP4 group was significantly reduced. Masson's trichrome staining showed that the collagen and fibrous cells in the si-SFRP4 group were more uniform, slender, parallel and regular. The above experimental results suggest that the proliferation and metabolism of palmar aponeurosis cells and the quality of metacarpal fascia xenografts were both significantly decreased. We speculated that nanoparticle-mediated SFRP4 siRNA can be used as a potential new method for the treatment of DD.
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Contractura de Dupuytren , Humanos , Contractura de Dupuytren/genética , Contractura de Dupuytren/terapia , Contractura de Dupuytren/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/uso terapéutico , Fascia/metabolismo , Colágeno , Proteínas Proto-OncogénicasRESUMEN
Angiogenesis is the critical media for tumor growth and migration. Tissue Inhibitor Matrix Metalloproteinase-1 (TIMP1) acts as an oncogene in colon carcinoma (CC), but the biological effects of TIMP1 on angiogenesis remain an open issue. This study sought to explore the exact function and mechanism of TIMP1 in the angiogenesis of CC. Bioinformatics methods were utilized to analyze the expression of TIMP1 and its upstream transcription factor FOS-like antigen 1 (FOSL1) in the tumor tissue of CC. Meanwhile, in CC cell lines, real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot were utilized to verify the expression of TIMP1 and FOSL1. Cell counting kit-8 and tube formation assays were utilized to analyze the proliferation and angiogenesis abilities of human umbilical vein endothelial cells (HUVECs). Western blot was used to detect the protein expression of VEGFA, VEGFR-2, and VEGFR-3. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were carried out to explore the specific interaction between FOSL1 and TIMP1. The present study discovered that TIMP1 and FOSL1 were evidently up-regulated in CC tissue and cells. Meanwhile, TIMP1 was found to participate in regulating the signaling pathway of vascular endothelial growth factor (VEGF). Silenced TIMP1 conspicuously suppressed the proliferation and angiogenesis of HUVECs and reduced the protein expression of VEGFA, VEGFR-2, and VEGFR-3. Moreover, FOSL1 could promote TIMP1 transcription by binding with its promoter and the inhibition of TIMP1 expression obviously reversed the promotion effects of FOSL1 overexpression on the proliferation and angiogenesis of HUVECs. FOSL1 activated VEGF pathway by up-regulating TIMP1 expression, thereby advancing CC angiogenesis. We provided theoretical basis that the FOSL1/TIMP1/VEGF pathway might be a novel option for anti-angiogenesis therapy of CC.
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Since the outbreak of novel coronavirus infection pneumonia in Wuhan City, China, in late 2019, such cases have been gradually reported in other parts of China and abroad. Children have become susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) because of their immature immune function. As the outbreak has progressed, more cases of novel coronavirus infection/pneumonia in children have been reported. Compared with adults, the impact of SARS-CoV-2 infection in children is less severe, with a lower incidence and susceptibility in children, which results in fewer children being tested, thereby underestimating the actual number of infections. Therefore, strengthening the diagnosis of the disease is particularly important for children, and early and clear diagnosis can determine treatment strategies and reduce the harm caused by the disease to children. According to the Novel Coronavirus Infection Pneumonia Diagnosis and Treatment Standards (trial version 7) issued by National Health Committee and the latest diagnosis and treatment strategies for novel coronavirus infection pneumonia in children, this review summarizes current strategies on diagnosis and treatment of SARS-CoV-2 infection in children.
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Antivirales/uso terapéutico , Betacoronavirus/genética , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/terapia , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , ARN Viral/sangre , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/uso terapéutico , Alanina/análogos & derivados , Alanina/uso terapéutico , Enfermedades Asintomáticas , Betacoronavirus/patogenicidad , Biomarcadores/sangre , COVID-19 , Prueba de COVID-19 , Niño , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Tos/diagnóstico , Combinación de Medicamentos , Diagnóstico Precoz , Fiebre/diagnóstico , Humanos , Hidroxicloroquina/uso terapéutico , Interferón-alfa/uso terapéutico , Lopinavir/uso terapéutico , Pandemias , Neumonía Viral/transmisión , Neumonía Viral/virología , Guías de Práctica Clínica como Asunto , ARN Viral/genética , Ribavirina/uso terapéutico , Ritonavir/uso terapéutico , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos XRESUMEN
RAF kinase inhibitor protein (RKIP) is a negative regulator of the RAS-mitogen-activated protein kinase/extracellular signal-regulated kinase signaling cascade. We investigated the expression of RKIP in chronic myelogenous leukemia (CML) K562 cells and the effects of RKIP on the characteristics of K562 cells. The recombinant plasmid pcDNA3.1-RKIP was established and transfected into K562 cells with the help of Lipofectamine 2000. At the same time, the RKIP-siRNA was transfected into K562 cells in another group. The expressions of RKIP in all groups were assayed by Western blot after 48 h. MTT (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to analyze the cell viability. Flow cytometry (FCM) was used to examine the cell cycle and cell apoptosis. Colony forming unit (CFU) assay was used to analyze the effect of RKIP on the clonogenic growth of CML cells. Western blot or luciferase reporter assay was used to detect the effect of RKIP on the level of phospho-ERK1/2 or the transcriptional activity of NF-κB. Western blot analysis showed that the plasmid pcDNA3.1-RKIP or RKIP-siRNA significantly enhanced or decreased RKIP expression (p < 0.01), respectively. In addition, MTT, FCM, and CFU assay indicated that the overexpression of RKIP significantly lowered the cell viability, cell proliferation and the clonogenic growth (p < 0.05), but improved cell apoptosis (p < 0.01). Western blot analysis or luciferase reporter assay showed that the level of phospho-ERK1/2 or the transcriptional activity of NF-κB was strongly inhibited by overexpression of RKIP. All these results could bring us a new perspective for biological therapy in myelogenous leukemia in the future.
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Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Apoptosis/fisiología , Western Blotting , Proliferación Celular , Citometría de Flujo , Humanos , Células K562 , ARN Interferente Pequeño , TransfecciónRESUMEN
BACKGROUND: Severe peripheral nerve injury, especially the long-distance peripheral nerve defect, causes severe functional disability in patients. There is always a lack of effective repair methods for clinic, and those in practice are associated with side effects. A case study was performed to observe the regenerative outcomes of the surgical repair of long-distance peripheral nerve defects in the upper arm with chitosan-poly(glycolide-co-lactide) (PGLA) nerve grafts combined with bone marrow mononuclear cells (BMMCs). METHODS: The right upper arm of a 29-year-old woman was injured, leaving a 50-mm-long median nerve defect, an 80-mm-long ulnar nerve defect, and muscle and blood vessel disruptions. The nerve defects were repaired by implanting BMMC-containing chitosan-PGLA nerve grafts on the 40th day after injury. A series of functional assessments were carried out from 2 weeks to 66 months after surgical repair. Sensory function was assessed by the pinprick test, two-point discrimination test and Semmes-Weinstein monofilament test. Motor function was evaluated by the range of motion of the wrist joint and muscle power. Autonomic function was monitored by laser-Doppler perfusion imaging (LDPI). Tissue morphology was observed through ultrasonic investigations. RESULTS: No adverse events, such as infection, allergy, or rejection, caused by the treatment were detected during the follow-up period. Sensory and pinprick nociception in the affected thumb, index, and middle fingers gradually restored at 6th month after surgery. The monofilament tactile sensation was 0.4 g in the terminal finger pulp of the thumb and index finger, 2.0 g in the middle finger, and greater than 300 g in the ring finger and little finger at the 66th month. Motor function recovery was detected at the 5th month after surgery, when the muscle strength of the affected forearm flexors began to recover. At the 66th month after surgery, the patient's forearm flexor strength was grade 4, with 80° of palmar flexion, 85° of dorsal extension, 8° of radial deviation, 40° of ulnar deviation, 40° of anterior rotation, and 85° of posterior rotation of the affected wrist. The patient could perform holding, picking up, and some other daily activities with the affected hand. The patient's sweating function of the affected hand was close to the level of the healthy hand. LDPI showed that the skin blood flow perfusion was significantly increased, with perfusion similar to on the normal side in some areas. Neuromusculoskeletal ultrasonography showed the presence of nerve structures. CONCLUSION: These results suggest that chitosan-PGLA nerve grafts combined with BMMCs could effectively repair long-distance nerve defects and achieve good clinical results.
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Quitosano , Procedimientos de Cirugía Plástica , Adulto , Péptidos Catiónicos Antimicrobianos , Brazo/cirugía , Médula Ósea , Femenino , Humanos , Nervio Mediano/lesiones , Nervio Mediano/cirugía , Procedimientos de Cirugía Plástica/métodos , Resultado del Tratamiento , Nervio Cubital/lesiones , Nervio Cubital/cirugíaRESUMEN
OBJECTIVE: To observe the effects of penetrating technique of scalp acupuncture on emotion, sleep and function development in children of autism spectrum disorder (ASD). METHODS: A total of 60 SAD children aged 3 to 6 years were randomized in a control group (music education rehabilitation,n=30) and an observation group (penetrating technique of scalp acupuncture + music education rehabilitation,n=30). In the two groups, the treatment for 3 months was as 1 course, and 2 courses of treatment were required. Before and after treatment, the changes were observed in childhood autism rating scale (CARS), emotion regulation subscale (ER), children's sleep habits questionnaire (CSHQ) and children autism and psycho-educational profile for autistic and developmentally disabled children (C-PEP-3), separately. RESULTS: Compared with the scores before treatment, CARS score, the score of each subscale of CSHQ, e.g. bedtime resistance, sleep onset delay, irregular sleep duration, sleep anxiety, parasomnias and daytime sleepiness as well as the total score of CSHQ were all reduced in children of two groups (P<0.05); and the score of ER and C-PEP-3 were all increased (P<0.05) after 6 months' treatment. Compared with the control group, ER score was increased in 3 and 6 months after treatment (P<0.05), CARS score was reduced (P<0.05) and C-PEP-3 score was increased obviously (P<0.05) 6 months after treatment in the observation group; but the scores of the subscale for night waking and sleep disordered breathing did not changed noticeably (P > 0.05). CONCLUSION: Penetrating technique of scalp acupuncture improves the emotion and sleep disorder and promotes the function development in ASD children.
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Terapia por Acupuntura , Trastorno del Espectro Autista , Trastornos del Sueño-Vigilia , Trastorno del Espectro Autista/terapia , Niño , Humanos , Cuero Cabelludo , SueñoRESUMEN
Nerve conduits filled with longitudinal aligned filaments have demonstrated a better regenerative outcome for bridging large peripheral nerve gaps than hollow nerve conduits. In the present study, we investigated the in vitro and in vitro cellular behavior of Schwann cells on polyglycolic acid (PGA) filaments by immunocyto/histochemistry and light/electron microscopy. After 1-3-week culture of rat dorsal root ganglia (DRGs) onto PGA filaments, Schwann cells from rat DRGs adhered to and migrated along PGA filaments. Twenty-four rats received implantation of chitosan conduits inserted with PGA filaments to bridge 10-mm-long sciatic nerve gaps. At 1, 2, 3 and 4 weeks post-implantation (n = 6, each time point), Schwann cells were found to migrate along PGA filaments and form cell columns resembling bands of Büngner. These results suggest that PGA filaments may play a contact guidance role in Schwann cell migration and thus serve as a promising conduit-filling material to facilitate peripheral nerve repair.
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Movimiento Celular/fisiología , Ácido Poliglicólico/química , Células de Schwann/citología , Animales , Animales Recién Nacidos , Ganglios Espinales/citología , Ganglios Espinales/fisiología , Inmunohistoquímica , Masculino , Microscopía Electrónica de Rastreo , Regeneración Nerviosa/fisiología , Ácido Poliglicólico/farmacología , Ratas , Ratas Sprague-Dawley , Células de Schwann/trasplante , Células de Schwann/ultraestructuraRESUMEN
We have developed a chitosan/polyglycolic acid (PGA) artificial nerve graft which was previously used for bridge implantation of dog sciatic nerves across 30-mm long defects. Here we describe a clinical trial of this graft for repairing a 35-mm-long median nerve defect at elbow of a human patient. During the 3-year follow-up period, functional recovery of the injured median nerve was assessed by pinch gauge test, hydraulic hand dynamometry, static two-point discrimination and touch test with monofilaments, in couple with electrophysiological examinations. The motor and sensory function of the median nerve demonstrated an ongoing recovery postimplantation, reaching M4 and S3+ levels during the follow-up period. The results indicate that the chitosan/PGA artificial nerve graft could be used for surgical repair of larger defects in major peripheral nerves at a higher level in the human.
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Quitosano/uso terapéutico , Nervio Mediano/lesiones , Nervio Mediano/cirugía , Ácido Poliglicólico/uso terapéutico , Prótesis e Implantes , Humanos , Masculino , Nervio Mediano/fisiología , Persona de Mediana Edad , Regeneración Nerviosa , Fuerza de Pellizco , Implantación de Prótesis , TactoRESUMEN
Silk fibroin (SF)-derived silkworms represent a type of highly biocompatible biomaterial for tissue engineering. We have previously investigated biocompatibility of SF with neural cells isolated from the central nervous system or peripheral nerve system in vitro, and also developed a SF-based nerve graft conduit or tissue-engineered nerve grafts by introducing bone marrow mesenchymal stem cells, as support cells, into SF-based scaffold and evaluated the outcomes of peripheral nerve repair in a rat model. As an extension of the previous study, the electrospun technique was performed here to fabricate SF-based neural scaffold inserted with silk fibres for bridging a 30-mm-long sciatic nerve gap in dogs. Assessments including functional, histological and morphometrical analyses were applied 12â months after surgery. All the results indicated that the SF-based neural scaffold group achieved satisfactory regenerative outcomes, which were close to those achieved by autologous nerve grafts as the golden-standard for peripheral nerve repair. Overall, our results raise a potential possibility for the translation of SF-based electrospun neural scaffolds as an alternative to nerve autografts into the clinic.
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Fibroínas/farmacología , Nervio Ciático/fisiología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Potenciales de Acción/efectos de los fármacos , Animales , Conducta Animal , Perros , Análisis de la Marcha , Masculino , Músculos/efectos de los fármacos , Músculos/fisiología , Regeneración Nerviosa/efectos de los fármacos , Recuperación de la Función/efectos de los fármacos , Nervio Ciático/efectos de los fármacos , Nervio Ciático/cirugíaRESUMEN
OBJECTIVE: B cell multiplication plays a key role in infections mononucleosis. The present study was designed to detect the expression of B-lymphocyte stimulator (BLyS) mRNA in peripheral blood using real-time fluorescence quantitative polymerase chain reaction (RFQ-PCR) in children with infectious mononucleosis in order to explore the role of BLys in this disorder. METHODS: Specific primers and TaqMan probes of BLyS were designed, and fluorescence of the PCR products were detected continuously during amplification. According to the standard curves created by plasmid DNA, the expression level of target genes in clinical samples were calculated using Stata Software version 8.0, and the results were presented as the ratio of copies of target gene mRNA to beta2 microglobulin (beta2M) mRNA copies. BLyS mRNA expression in peripheral blood was measured by RFQ-PCR in 18 children with infectious mononucleosis and the results were compared with those measured in 15 healthy controls. RESULTS: The range of target gene mRNA detected by REQ-PCR was from 109 ng/L to 101 ng/L. The coefficient of variation for intra-experimental and inter-experimental reproducibility ranged from 1.88% to 5.89% and 6.32% to 12.34%, respectively. BLyS mRNA expression in peripheral blood in children with infectious mononucleosis were significantly higher than that in controls (1.65+/-0.10 vs 0.56+/-0.08; P < 0.01). CONCLUSIONS: RFQ-PCR has a high sensitivity and reproducibility for the measurement of BLyS mRNA expression. BLyS may be involved in the development of infectious mononucleosis.
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Factor Activador de Células B/genética , Mononucleosis Infecciosa/metabolismo , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/análisis , Niño , Preescolar , Femenino , Fluorescencia , Humanos , Mononucleosis Infecciosa/etiología , MasculinoRESUMEN
To advance molecular and cellular therapy into the clinic for peripheral nerve injury, modification of neural scaffolds with the extracellular matrix (ECM) of peripheral nerves has been established as a promising alternative to direct inclusion of support cells and/or growth factors within a neural scaffold, while cell-derived ECM proves to be superior to tissue-derived ECM in the modification of neural scaffolds. Based on the fact that bone marrow mesenchymal stem cells (BMSCs), just like Schwann cells, are adopted as support cells within a neural scaffold, in this study we used BMSCs as parent cells to generate ECM for application in peripheral nerve tissue engineering. A chitosan nerve guidance conduit (NGC) and silk fibroin filamentous fillers were respectively prepared for co-culture with purified BMSCs, followed by decellularization to stimulate ECM deposition. The ECM-modified NGC and lumen fillers were then assembled into a chitosan-silk fibroin-based, BMSC-derived, ECM-modified neural scaffold, which was implanted into rats to bridge a 10 mm-long sciatic nerve gap. Histological and functional assessments after implantation showed that regenerative outcomes achieved by our engineered neural scaffold were better than those achieved by a plain chitosan-silk fibroin scaffold, and suggested the benefits of BMSC-derived ECM for peripheral nerve repair. Copyright © 2016 John Wiley & Sons, Ltd.
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Células de la Médula Ósea/metabolismo , Matriz Extracelular/química , Células Madre Mesenquimatosas/metabolismo , Nervios Periféricos/metabolismo , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Células de la Médula Ósea/patología , Quitosano/química , Matriz Extracelular/metabolismo , Fibroínas/química , Células Madre Mesenquimatosas/patología , Traumatismos de los Nervios Periféricos/metabolismo , Traumatismos de los Nervios Periféricos/patología , Traumatismos de los Nervios Periféricos/terapia , Nervios Periféricos/patología , Ratas , Ratas Sprague-DawleyRESUMEN
Extracellular/acellular matrix-containing neural scaffolds represent a promising design of a tissue engineered nerve graft (TENG) for peripheral nerve repair. In this study, we engineered a composite neural scaffold by culturing dog bone marrow mesenchymal stem cells (BMSCs) onto the surface of a chitosan/silk fibroin-based scaffold and then exposing the cell culture to decellularization to deposit acellular matrix (ACM) coatings on the scaffold. This natural biomaterial-based, cell-derived ACM-coated neural scaffold, as a novel nerve graft, was used to bridge a 60 mm long nerve gap in a dog sciatic nerve. At 12 months after grafting, behavioral, functional, and histological evaluation indicated that our developed neural scaffold achieved satisfactory regenerative outcomes, which were very close to those achieved by autologous nerve grafts, the accepted golden standard for peripheral nerve repair. Moreover, additional therapeutic benefits produced by the modification of a neural scaffold with BMSC-derived ACM may be associated with the unique neural activity of the ACM, as evidenced by in vitro experimental findings that the ACM significantly enhanced axonal regrowth and Schwann cell proliferation. Our results will provide a further experimental basis for the translation of ACM-containing neural scaffolds into the clinic.
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Cutaneous vasoconstriction/vasodilatation occurs in response to whole body and local cooling/heating, and the vasomotor activities play a pivotal role in thermal control of the human body. The mechanisms underlying regulation of skin blood flow involve both neurogenic and humeral/local chemical influence, contributing to the initial response to thermal stimuli and the prolonged phase of response, respectively. Previous studies have suggested the impairment of cutaneous thermal regulation after nerve injury. However, the evidence regarding how the skin perfusion and thermoregulatory response evolve after nerve injury and repair remains limited. Here we observed, by utilizing laser-Doppler perfusion imaging, baseline skin perfusion and perfusion change in response to thermal stimuli after median and ulnar nerve injury, and the results showed that baseline perfusion in autonomous skin area profoundly decreased and active rewarming after clod stress dramatically diminished before sensory recovery of the skin became detectable. In addition, baseline cutaneous perfusion was recovered as the skin regained touch sensation, and exhibited positive correlation to touch sensibility of the skin. These data indicate that both active perfusion and thermoregulatory response of the skin are markedly compromised during skin denervation and can be recovered by re-innervation. This suggests the importance of timely repair of injured nerve, especially in the practice of replantation.
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Regulación de la Temperatura Corporal/fisiología , Mano/irrigación sanguínea , Nervio Mediano/lesiones , Flujo Sanguíneo Regional/fisiología , Piel/irrigación sanguínea , Nervio Cubital/lesiones , Adulto , Femenino , Mano/inervación , Mano/fisiología , Humanos , Flujometría por Láser-Doppler , Masculino , Persona de Mediana Edad , Reflejo/fisiología , Piel/inervación , Estrés Fisiológico/fisiología , Tacto/fisiología , Adulto JovenRESUMEN
The therapeutic benefits of bone marrow mononuclear cells (BM-MNCs) in many diseases have been well established. To advance BM-MNC-based cell therapy into the clinic for peripheral nerve repair, in this study we developed a new design of tissue-engineered nerve grafts (TENGs), which consist of a chitosan/fibroin-based nerve scaffold and BM-MNCs serving as support cells. These TENGs were used for interpositional nerve grafting to bridge a 10-mm-long sciatic nerve defect in rats. Histological and functional assessments after nerve grafting showed that regenerative outcomes achieved by our developed TENGs were better than those achieved by chitosan/silk fibroin scaffolds and were close to those achieved by autologous nerve grafts. In addition, we used green fluorescent protein-labeled BM-MNCs to track the cell location within the chitosan/fibroin-based nerve scaffold and trace the cell fate at an early stage of sciatic nerve regeneration. The result suggested that BM-MNCs could survive at least 2 weeks after nerve grafting, thus helping to gain a preliminary mechanistic insight into the favorable effects of BM-MNCs on axonal regrowth.
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Células de la Médula Ósea/citología , Trasplante de Médula Ósea/métodos , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Quitosano/metabolismo , Leucocitos Mononucleares/trasplante , Regeneración Nerviosa/fisiología , Nervio Ciático/cirugía , Animales , Femenino , Fibroínas/metabolismo , Leucocitos Mononucleares/citología , Ratas , Ratas Sprague-Dawley , Nervio Ciático/patología , Ingeniería de Tejidos/métodos , Andamios del Tejido , Cicatrización de Heridas/fisiologíaRESUMEN
Fluorescent neuronal tracers should not be toxic to the nervous system when used in long-term labeling. Previous studies have addressed tracer toxicity, but whether tracers injected into an intact nerve result in functional impairment remains to be elucidated. In the present study, we examined the functions of motor, sensory and autonomic nerves following the application of 5% Fluoro-Gold, 4% True Blue and 10% Fluoro-Ruby (5 µL) to rat tibial nerves via pressure injection. A set of evaluation methods including walking track analysis, plantar test and laser Doppler perfusion imaging was used to determine the action of the fluorescent neuronal tracers. Additionally, nerve pathology and ratio of muscle wet weight were also observed. Results showed that injection of Fluoro-Gold significantly resulted in loss of motor nerve function, lower plantar sensibility, increasing blood flow volume and higher neurogenic vasodilatation. Myelinated nerve fiber degeneration, unclear boundaries in nerve fibers and high retrograde labeling efficacy were observed in the Fluoro-Gold group. The True Blue group also showed obvious neurogenic vasodilatation, but less severe loss of motor function and degeneration, and fewer labeled motor neurons were found compared with the Fluoro-Gold group. No anomalies of motor and sensory nerve function and no myelinated nerve fiber degeneration were observed in the Fluoro-Ruby group. Experimental findings indicate that Fluoro-Gold tracing could lead to significant functional impairment of motor, sensory and autonomic nerves, while functional impairment was less severe following True Blue tracing. Fluoro-Ruby injection appears to have no effect on neurological function.
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This paper describes a clinical case study in which a chitosan/polyglycolic acid nerve guidance conduit (chitosan-PGA NGC) was utilized to repair a 30 mm long median nerve defect in the right distal forearm of a 55 year-old male patient. Thirty-six months after the nerve repair, the palm abduction of the thumb and the thumb-index digital opposition recovered, facilitating the patient to accomplish fine activities, such as handling chopsticks. Static two-point discrimination measured 14, 9 and 9 mm in the thumb, index and middle fingers of the right hand. Reproducible compound muscle action potentials were recorded on the right abductor pollicis. The ninhydrin test, a classical method for assessing sympathetic nerve function, showed partial recovery of the perspiration function of the injured thumb, index and middle fingers. This repair case suggested a possible strategy for the clinical reconstruction of extended defects in human peripheral nerve trunks by the implantation of chitosan-PGA NGCs.