RESUMEN
The energetic driving force for electron transfer must be minimized to realize efficient optoelectronic devices including organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). Exploring the dynamics of a charge-transfer (CT) state at an interface leads to a comprehension of the relationship between energetics, electron-transfer efficiency, and device performance. Here, we investigate the electron transfer from the CT state to the triplet excited state (T1) in upconversion OLEDs with 45 material combinations. By analyzing the CT emission and the singlet excited-state emission from triplet-triplet annihilation via the dark T1, their energetics and electron-transfer efficiencies are extracted. We demonstrate that the CTâT1 electron transfer is enhanced by the stronger CT interaction and a minimal energetic driving force (<0.1â eV), which is explained using the Marcus theory with a small reorganization energy of <0.1â eV. Through our analysis, a novel donor-acceptor combination for the OLED is developed and shows an efficient blue emission with an extremely low turn-on voltage of 1.57â V. This work provides a solution to control interfacial CT states for efficient optoelectronic devices without energy loss.
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A protocol for the stereodivergent pentafluoroethylation of N-sulfinylimines using HFC-125 with KHMDS/triglyme has been developed. Both diastereomers of the pentafluoroethylated amines can be selectively synthesized based on the presence or absence of triglyme. This additive-controlled protocol allows the KHMDS/triglyme cryptate to be a straightforward and cheap alternative to previously reported base-controlled stereodivergent trifluoromethylation using potassium hexamethyldisilazide (KHMDS) versus P4-tBu.
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Éteres Corona , Fluorocarburos , PolietilenglicolesRESUMEN
BACKGROUND: Bone marrow stem cell clonal dysfunction by somatic mutation is suspected to affect post-infarction myocardial regeneration after coronary bypass surgery (CABG). METHODS: Transcriptome and variant expression analysis was studied in the phase 3 PERFECT trial post myocardial infarction CABG and CD133+ bone marrow derived hematopoetic stem cells showing difference in left ventricular ejection fraction (∆LVEF) myocardial regeneration Responders (n=14; ∆LVEF +16% day 180/0) and Non-responders (n=9; ∆LVEF -1.1% day 180/0). Subsequently, the findings have been validated in an independent patient cohort (n=14) as well as in two preclinical mouse models investigating SH2B3/LNK antisense or knockout deficient conditions. FINDINGS: 1. Clinical: R differed from NR in a total of 161 genes in differential expression (n=23, q<0â¢05) and 872 genes in coexpression analysis (n=23, q<0â¢05). Machine Learning clustering analysis revealed distinct RvsNR preoperative gene-expression signatures in peripheral blood acorrelated to SH2B3 (p<0.05). Mutation analysis revealed increased specific variants in RvsNR. (R: 48 genes; NR: 224 genes). 2. Preclinical:SH2B3/LNK-silenced hematopoietic stem cell (HSC) clones displayed significant overgrowth of myeloid and immune cells in bone marrow, peripheral blood, and tissue at day 160 after competitive bone-marrow transplantation into mice. SH2B3/LNK-/- mice demonstrated enhanced cardiac repair through augmenting the kinetics of bone marrow-derived endothelial progenitor cells, increased capillary density in ischemic myocardium, and reduced left ventricular fibrosis with preserved cardiac function. 3. VALIDATION: Evaluation analysis in 14 additional patients revealed 85% RvsNR (12/14 patients) prediction accuracy for the identified biomarker signature. INTERPRETATION: Myocardial repair is affected by HSC gene response and somatic mutation. Machine Learning can be utilized to identify and predict pathological HSC response. FUNDING: German Ministry of Research and Education (BMBF): Reference and Translation Center for Cardiac Stem Cell Therapy - FKZ0312138A and FKZ031L0106C, German Ministry of Research and Education (BMBF): Collaborative research center - DFG:SFB738 and Center of Excellence - DFG:EC-REBIRTH), European Social Fonds: ESF/IV-WM-B34-0011/08, ESF/IV-WM-B34-0030/10, and Miltenyi Biotec GmbH, Bergisch-Gladbach, Germany. Japanese Ministry of Health : Health and Labour Sciences Research Grant (H14-trans-001, H17-trans-002) TRIAL REGISTRATION: ClinicalTrials.gov NCT00950274.
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Antígeno AC133/genética , Trasplante de Médula Ósea/métodos , Enfermedad de la Arteria Coronaria/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Isquemia Miocárdica/terapia , Adolescente , Adulto , Anciano , Células de la Médula Ósea/citología , Senescencia Celular/genética , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Corazón/crecimiento & desarrollo , Corazón/fisiopatología , Células Madre Hematopoyéticas/citología , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/genética , Isquemia Miocárdica/patología , Regeneración/genética , Adulto JovenRESUMEN
Quantitative and qualitative impairment of endothelial progenitor cells (EPCs) limits the efficacy of autologous cell therapy in patients with cardiovascular diseases. Here, we developed a serum-free quality and quantity control culture system for colony-forming EPCs to enhance their regenerative potential. A culture with serum-free medium containing stem cell factor, thrombopoietin, vascular endothelial growth factor, interleukin-6, and Flt-3 ligand was determined as optimal quality and quantity culture (QQc) in terms of the most vasculogenic colony-forming EPC expansion, evaluated by the newly established EPC colony formation assay. The QQc of umbilical cord blood-CD133(+) cells for 7 days produced a 52.9-fold increase in total cell number and 3.28-fold frequency in definitive EPC colony development, resulting in a 203.9-fold increase in estimated total definitive EPC colony number in vitro. Pre- or post-QQc cells were intramyocardially transplanted into nude rats with myocardial infarction (MI). Echocardiographic and micromanometer-tipped conductance catheter examinations 28 days post-MI revealed significant preservation of left ventricular (LV) function in rats receiving pre- or post-QQc cells compared with those receiving phosphate-buffered saline. Assessments of global LV contractility indicated a dose-dependent effect of pre- or post-QQc cells and the superior potency of post-QQc cells over pre-QQc cells. Furthermore, immunohistochemistry showed more abundant formation of both human and rat endothelial cells and cardiomyocytes in the infarcted myocardium following transplantation of post-QQc cells compared with pre-QQc cells. Our optimal serum-free quality and quantity culture may enhance the therapeutic potential of EPCs in both quantitative and qualitative aspects for cardiovascular regeneration.
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Técnicas de Cultivo de Célula/métodos , Ensayo de Unidades Formadoras de Colonias/métodos , Medio de Cultivo Libre de Suero/metabolismo , Células Endoteliales/citología , Neovascularización Fisiológica , Células Madre/citología , Antígeno AC133 , Animales , Antígenos CD/metabolismo , Tampones (Química) , Recuento de Células , Técnicas de Cultivo de Célula/normas , Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Tratamiento Basado en Trasplante de Células y Tejidos/normas , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias/normas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Ecocardiografía , Células Endoteliales/metabolismo , Células Endoteliales/trasplante , Sangre Fetal/citología , Sangre Fetal/metabolismo , Glicoproteínas/metabolismo , Humanos , Inmunohistoquímica , Contracción Miocárdica , Infarto del Miocardio/metabolismo , Infarto del Miocardio/terapia , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/trasplante , Péptidos/metabolismo , Control de Calidad , Ratas , Ratas Desnudas , Células Madre/metabolismo , Función Ventricular IzquierdaRESUMEN
RATIONALE: Despite preclinical success in regenerating and revascularizing the infarcted heart using angiogenic growth factors or bone marrow (BM) cells, recent clinical trials have revealed less benefit from these therapies than expected. OBJECTIVE: We explored the therapeutic potential of myocardial gene therapy of placental growth factor (PlGF), a VEGF-related angiogenic growth factor, with progenitor-mobilizing activity. METHODS AND RESULTS: Myocardial PlGF gene therapy improves cardiac performance after myocardial infarction, by inducing cardiac repair and reparative myoangiogenesis, via upregulation of paracrine anti-apoptotic and angiogenic factors. In addition, PlGF therapy stimulated Sca-1(+)/Lin(-) (SL) BM progenitor proliferation, enhanced their mobilization into peripheral blood, and promoted their recruitment into the peri-infarct borders. Moreover, PlGF enhanced endothelial progenitor colony formation of BM-derived SL cells, and induced a phenotypic switch of BM-SL cells, recruited in the infarct, to the endothelial, smooth muscle and cardiomyocyte lineage. CONCLUSIONS: Such pleiotropic effects of PlGF on cardiac repair and regeneration offer novel opportunities in the treatment of ischemic heart disease.
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Células de la Médula Ósea/citología , Isquemia Miocárdica/metabolismo , Neovascularización Patológica , Proteínas Gestacionales/metabolismo , Células Madre/citología , Animales , Proliferación Celular , Electrocardiografía/métodos , Femenino , Técnicas de Transferencia de Gen , Proteínas Fluorescentes Verdes/química , Hemodinámica , Humanos , Masculino , Ratones , Ratones Transgénicos , Isquemia Miocárdica/terapia , Miocardio/patología , Fenotipo , Factor de Crecimiento Placentario , Ratas , Ratas Sprague-Dawley , RegeneraciónRESUMEN
BACKGROUND: Treatment of complex aortic pathologies involving the transverse arch with extensive involvement of the descending aorta remains a surgical challenge. Since clamshell incision provides superior exposure of the entire thoracic aorta, we evaluated the use of this technique for single-stage total arch replacement by arch vessel reconstruction. METHODS: The arch-first technique combined with clamshell incision was used in 38 cases of aneurysm and aortic disease in 2008 and 2009. Extensive total arch replacement was used with clamshell incision for reconstruction of arch vessels under deep hypothermic circulatory arrest. RESULTS: Overall 30-day mortality was 13%. The mean operating time was approximately 8 hours. Deep hypothermia resulted in mean CPB time exceeding 4.5 hours and mean duration of circulatory arrest was 25 minutes. The overall postoperative temporary and permanent neurologic dysfunction rates were 3% and 3% for elective and 3% and 0% for emergency surgery, respectively. All patients except the five who died in hospital were discharged without nursing care after an average post-operative hospital stay of 35 days. CONCLUSIONS: The arch-first technique, combined with clamshell incision, provides expeditious replacement of the thoracic aorta with an acceptable duration of hypothermic circulatory arrest and minimizes the risk of retrograde atheroembolism by using antegrade perfusion.
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Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/métodos , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Torácica/mortalidad , Implantación de Prótesis Vascular/mortalidad , Distribución de Chi-Cuadrado , Paro Circulatorio Inducido por Hipotermia Profunda , Femenino , Mortalidad Hospitalaria , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Resultado del TratamientoRESUMEN
This case report concerns a 59-year-old man with acute myocardial infarction associated with a giant organized thrombus occupying the right sinus of Valsalva that developed into chest pain and bradycardia. Magnetic resonance imaging showed low intensity in both T1-weighted and T2-weighted images, indicating that the mass was a thrombus. A direct approach involving grafting effectively resolved the embolization and myocardial ischemia, even during the subacute period.
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Aorta Torácica/cirugía , Enfermedades de la Aorta/complicaciones , Puente de Arteria Coronaria/métodos , Infarto del Miocardio/cirugía , Seno Aórtico , Trombectomía/métodos , Trombosis/complicaciones , Aorta Torácica/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico , Enfermedades de la Aorta/cirugía , Prótesis Vascular , Angiografía Coronaria , Diagnóstico Diferencial , Ecocardiografía , Electrocardiografía , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/etiología , Trombosis/diagnóstico , Trombosis/cirugía , Tomografía Computarizada por Rayos XRESUMEN
We present a new, less-invasive technique for a re-do for perivalvular leakage after aortic mechanical valve replacement. Only the carbon ring of the previously implanted St. Jude prosthesis was excised, the sewing cuff being preserved. The locations of the perivalvular defects were clearly identified by pulling the sewing cuff inward. They were securely closed by placing pledgeted sutures at the preserved cuff through the full thickness of the aortic wall or through the annulus by a deep bite from the left ventricular side. A new mechanical prosthesis was then sewn onto the preserved sewing cuff.
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Insuficiencia de la Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Falla de Prótesis , Técnicas de Sutura , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Reoperación , Resultado del TratamientoRESUMEN
The therapeutic potential of hematopoietic stem cells/endothelial progenitor cells (HSCs/EPCs) for fracture healing has been demonstrated with evidence for enhanced vasculogenesis/angiogenesis and osteogenesis at the site of fracture. The adaptor protein Lnk has recently been identified as an essential inhibitor of stem cell factor (SCF)-cKit signaling during stem cell self-renewal, and Lnk-deficient mice demonstrate enhanced hematopoietic reconstitution. In this study, we investigated whether the loss of Lnk signaling enhances the regenerative response during fracture healing. Radiological and histological examination showed accelerated fracture healing and remodeling in Lnk-deficient mice compared with wild-type mice. Molecular, physiological, and morphological approaches showed that vasculogenesis/angiogenesis and osteogenesis were promoted in Lnk-deficient mice by the mobilization and recruitment of HSCs/EPCs via activation of the SCF-cKit signaling pathway in the perifracture zone, which established a favorable environment for bone healing and remodeling. In addition, osteoblasts (OBs) from Lnk-deficient mice had a greater potential for terminal differentiation in response to SCF-cKit signaling in vitro. These findings suggest that inhibition of Lnk may have therapeutic potential by promoting an environment conducive to vasculogenesis/angiogenesis and osteogenesis and by facilitating OB terminal differentiation, leading to enhanced fracture healing.
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Curación de Fractura , Osteogénesis , Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Factor de Células Madre/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Diferenciación Celular , Fracturas Óseas/metabolismo , Fracturas Óseas/fisiopatología , Fracturas Óseas/terapia , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Péptidos y Proteínas de Señalización Intracelular , Proteínas de la Membrana , Ratones , Neovascularización Patológica , Neovascularización Fisiológica , Osteoblastos/metabolismo , Osteoblastos/patología , Osteogénesis/genética , Proteínas/genética , Transducción de Señal , Células Madre/metabolismo , Células Madre/patologíaRESUMEN
Popliteal artery entrapment syndrome (PAES) is a rare cause of acute limb ischemia in adult patients but commonly demonstrates as claudication in young patients. The most significant, although rare, complication associated with PAES is aneurysm formation. We present the case of an elderly patient with a unilateral popliteal artery aneurysm owing to symptomatic anatomic entrapment. This report presents the oldest patient ever reported with this syndrome and highlights the advantage of multimodal treatment. As multidetector computed tomography highly contributed to the rapid diagnostic confirmation and choice of treatment in the popliteal fossa, limb salvage was achieved in this patient.
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Aneurisma/etiología , Arteriopatías Oclusivas/complicaciones , Isquemia/etiología , Extremidad Inferior/irrigación sanguínea , Arteria Poplítea , Trombosis/complicaciones , Enfermedad Aguda , Anciano , Aneurisma/diagnóstico por imagen , Aneurisma/cirugía , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Humanos , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Recuperación del Miembro , Masculino , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Vena Safena/trasplante , Trombectomía , Trombosis/diagnóstico por imagen , Trombosis/cirugía , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
This case report concerns a 62-year-old woman with spontaneous infrarenal abdominal aortic dissection, which developed into claudication and rest pain in the lower extremity. Multi-row detector computed tomography showed the entry site of the abdominal aortic dissection at the second lumbar artery, while the reentry site was found intraoperatively at the median sacral artery, indicating that the false lumen had progressed and compressed the true lumen. A direct approach involving grafting appears to be an effective procedure for resolving mesenteric and lower extremity hypoperfusion due to aortic dissection with a dilated false channel, even during the acute period.
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Aneurisma de la Aorta Abdominal/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular , Extremidad Inferior/irrigación sanguínea , Disección Aórtica/complicaciones , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/fisiopatología , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/fisiopatología , Aortografía/métodos , Femenino , Humanos , Persona de Mediana Edad , Dolor/etiología , Flujo Sanguíneo Regional , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
OBJECTIVE: Unrestricted somatic stem cells (USSCs) were successfully identified from human cord blood. However, the efficacy of USSC transplantation for improving left ventricular (LV) function post myocardial infarction (MI) is still controversial. METHODS AND RESULTS: PBS, 1x10(6) human fibroblasts (Fbr), 1x10(5) USSCs (LD), or 1x10(6) USSCs (HD) were transplanted intramyocardially 20 minutes after ligating the LAD of nude rats. Echocardiography and a microtip conductance catheter at day 28 revealed a dose-dependent improvement of LV function after USSC transplantation. Necropsy examination revealed dose-dependent augmentation of capillary density and inhibition of LV fibrosis. Dual-label immunohistochemistry for cardiac troponin-I and human nuclear antigen (HNA) demonstrated that human cardiomyocytes (CMCs) were dose-dependently generated in ischemic myocardium 28 days after USSC transplantation. Similarly, dual-label immunostaining for smooth muscle actin and class I human leukocyte antigen or that for von Willebrand factor and HNA also revealed a dose-dependent vasculogenesis after USSC transplantation. RT-PCR indicated that expression of human-specific genes of CMCs, smooth muscle cells, and endothelial cell markers in infarcted myocardium were significantly augmented in USSC-treated animals compared with control groups. CONCLUSIONS: USSC transplantation leads to functional improvement and recovery from MI and exhibits a significant and dose-dependent potential for concurrent cardiomyogenesis and vasculogenesis.
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Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Circulación Coronaria/fisiología , Infarto del Miocardio/terapia , Células Madre Pluripotentes/trasplante , Remodelación Ventricular/fisiología , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Ecocardiografía , Femenino , Sangre Fetal/citología , Humanos , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/patología , Distribución Aleatoria , Ratas , Ratas Endogámicas F344 , Ratas Desnudas , Función Ventricular/fisiologíaRESUMEN
We recently reported that i.v. transplantation of adult human circulating CD34+ cells, an endothelial/hematopoietic progenitor-enriched cell population, contributes to fracture healing through the enhancement of vasculogenesis and osteogenesis. However, the scarcity of CD34+ cells in the adult human is a critical issue for the future clinical application of this method. To overcome this issue, we assessed in vitro and in vivo capacity of granulocyte colony-stimulating factor-mobilized peripheral blood (GM-PB) human CD34+ cells for vasculogenesis and osteogenesis. First, we confirmed the differentiation capability of GM-PB CD34+ cells into osteoblasts in vitro. Second, local transplantation of GM-PB CD34+ cells on atelocollagen scaffold was performed in nude rats in a model of unhealing fractures. Immunostaining for human leukocyte antigen-ABC of tissue samples 1 week after fracture and cell therapy showed the superior incorporation after local transplantation compared with systemic infusion. Third, the effects of local transplantation of 10(5) (Hi), 10(4) (Mid), or 10(3) (Lo) doses of GM-PB CD34+ cells or phosphate-buffered saline (PBS) on fracture healing were compared. Extrinsic vasculogenic and osteogenic differentiation of GM-PB CD34+ cells, enhancement of the intrinsic angio-osteogenesis by recipient cells, augmentation of blood flow recovery at the fracture sites, and radiological and histological confirmation of fracture healing were observed only in the Hi and Mid groups but not in the Lo and PBS groups. These results strongly suggest that local transplantation of GM-PB CD34+ cells with atelocollagen scaffold is a feasible strategy for therapeutic vasculogenesis and osteogenesis needed for fracture healing. Disclosure of potential conflicts of interest is found at the end of this article.
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Antígenos CD34/análisis , Fracturas Óseas/complicaciones , Fracturas Óseas/cirugía , Factor Estimulante de Colonias de Granulocitos/farmacología , Movilización de Célula Madre Hematopoyética , Trasplante de Células Madre , Cicatrización de Heridas , Adulto , Animales , Células de la Médula Ósea/citología , Capilares/fisiología , Diferenciación Celular , Citocinas/genética , Femenino , Humanos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteogénesis , ARN/genética , ARN/aislamiento & purificación , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Madre/citología , Células Madre/efectos de los fármacos , Trasplante HeterólogoRESUMEN
BACKGROUND: Cellular cardiomyoplasty for myocardial infarction has been developed using various cell types. However, complete differentiation and/or trans-differentiation into cardiomyocytes have never occurred in these transplant studies, whereas functional contributions were reported. METHODS AND RESULTS: Skeletal muscle interstitium-derived CD34(+)/CD45(-) (Sk-34) cells were purified from green fluorescent protein transgenic mice by flowcytometory. Cardiac differentiation of Sk-34 cells was examined by in vitro clonal culture and co-culture with embryonic cardiomyocytes, and in vivo transplantation into a nude rat myocardial infarction (MI) model (left ventricle). Lower relative expression of cardiomyogenic transcription factors, such as GATA-4, Nkx2-5, Isl-1, Mef2 and Hand2, was seen in clonal cell culture. However, vigorous expression of these factors was seen on co-culture with embryonic cardiomyocytes, together with formation of gap-junctions and synchronous contraction following sphere-like colony formation. At 4 weeks after transplantation of freshly isolated Sk-34 cells, donor cells exhibited typical cardiomyocyte structure with formation of gap-junctions, as well as intercalated discs and desmosomes, between donor and recipient and/or donor and donor cells. Fluorescence in situ hybridization (FISH) analysis detecting the rat and mouse genomic DNA and immunoelectron microscopy using anti-GFP revealed donor-derived cells. Transplanted Sk-34 cells were incorporated into infarcted portions of recipient muscles and contributed to cardiac reconstitution. Significant improvement in left ventricular function, as evaluated by transthoracic echocardiography and micro-tip conductance catheter, was also observed. CONCLUSIONS AND SIGNIFICANCE: Skeletal muscle-derived multipotent Sk-34 cells that can give rise to skeletal and smooth muscle cells as reported previously, also give rise to cardiac muscle cells as multi-myogenic stem cells, and thus are a potential source for practical cellular cardiomyoplasty.
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Trasplante de Células , Músculo Esquelético/citología , Miocardio/citología , Células Madre/citología , Animales , Diferenciación Celular , Técnicas de Cocultivo , Proteínas Fluorescentes Verdes/genética , Inmunofenotipificación , Hibridación Fluorescente in Situ , Ratones , Ratones Transgénicos , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
We recently reported that systemic administration of peripheral blood (PB) CD34+ cells, an endothelial progenitor cell (EPC)-enriched population, contributed to fracture healing via vasculogenesis/angiogenesis. However, pathophysiological role of EPCs in fracture healing process has not been fully clarified. Therefore, we investigated the hypothesis whether mobilization and incorporation of bone marrow (BM)-derived EPCs may play a pivotal role in appropriate fracture healing. Serial examinations of Laser doppler perfusion imaging and histological capillary density revealed that neovascularization activity at the fracture site peaked at day 7 post-fracture, the early phase of endochondral ossifification. Fluorescence-activated cell sorting (FACS) analysis demonstrated that the frequency of BM cKit+Sca1+Lineage- (Lin-) cells and PB Sca1+Lin- cells, which are EPC-enriched fractions, significantly increased post-fracture. The Sca1+ EPC-derived vasuculogenesis at the fracture site was confirmed by double immunohistochemistry for CD31 and Sca1. BM transplantation from transgenic donors expressing LacZ transcriptionally regulated by endothelial cell-specific Tie-2 promoter into wild type also provided direct evidence that EPCs contributing to enhanced neovascularization at the fracture site were specifically derived from BM. Animal model of systemic administration of PB Sca1+Lin- Green Fluorescent Protein (GFP)+ cells further confirmed incorporation of the mobilized EPCs into the fracture site for fracture healing. These findings indicate that fracture may induce mobilization of EPCs from BM to PB and recruitment of the mobilized EPCs into fracture sites, thereby augment neovascularization during the process of bone healing. EPCs may play an essential role in fracture healing by promoting a favorable environment through neovascularization in damaged skeletal tissue.
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Células de la Médula Ósea/patología , Huesos/patología , Movimiento Celular , Células Endoteliales/patología , Fracturas Óseas/patología , Células Madre/patología , Cicatrización de Heridas , Animales , Ataxina-1 , Ataxinas , Huesos/irrigación sanguínea , Fracturas Óseas/inducido químicamente , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , FenotipoRESUMEN
Nascent mesodermal cells derived from EB5 embryonic stem (ES) cells were sorted in terms of cardiogenic potential on the basis of their expression levels of platelet-derived growth factor receptor alpha (PDGFRalpha) and fetal liver kinase 1 (Flk-1). The sorted cells were cocultured with OP9 stromal cells to induce terminal differentiation into contractile cardiac colonies. A significant number of cardiac colonies were found in the Flk-1+/PDGFRalpha+ fraction. The enrichment double-positive fraction produced approximately fivefold more cardiac colonies than the Flk-1+/PDGFRalpha- fraction and 10-fold more than the Flk-1-/PDGFRalpha+ fraction. To investigate the involvement of these markers in embryonic cardiogenesis, the cells that disseminated from the E7.5-7.75 embryos were fractionated and seeded on OP9 cells. The cardiogenic potential was markedly enhanced in the Flk-1+/PDGFRalpha+ fraction. These results suggest that some of the precursor cells coexpressing these markers are selectively involved in cardiogenic events, and that the identification of ES-cell-derived precursors with these markers will contribute to the effective production of cardiomyocytes for cell therapies.
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Desarrollo Embrionario/fisiología , Células Madre Embrionarias/citología , Células Madre Embrionarias/fisiología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Biomarcadores/metabolismo , Diferenciación Celular , Línea Celular , Expresión Génica/fisiología , Ratones , Ratones Endogámicos ICR , Contracción Miocárdica/fisiologíaRESUMEN
A 23-year-old Japanese man was admitted with a chief complaint of abdominal pain. He was previously healthy, and his past medical history was unremarkable. Local tenderness and rebound tenderness at McBurney's point were elicited. Abdominal roentgenography was non-diagnostic. Ultrasonography and computed tomography showed a tumor with a central core. Based on a diagnosis of appendicitis with omental inflammation or an omental tumor, laparotomy performed. Intraoperatively, no site of gastrointestinal perforation was detected; however, a 5-cm omental granuloma was identified that proved to have a fishbone nucleus on pathological examination. The postoperative course was uneventful, and upper gastrointestinal endoscopy and barium enema were unremarkable. A large solitary omental pseudotumor is rare, and the clinical course in this case was atypical compared with the usual course of intestinal perforation by a foreign body and formation of an intra-abdominal granuloma.
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Granuloma de Cuerpo Extraño/diagnóstico , Granuloma de Células Plasmáticas , Epiplón , Enfermedades Peritoneales/diagnóstico , Adulto , Huesos , Granuloma de Células Plasmáticas/diagnóstico , Humanos , MasculinoRESUMEN
BACKGROUND: Therapeutic effect of stem cell transplantation (SCTx) for myocardial neovascularization has been evaluated by histological capillary density in small animals. However, it has been technically difficult to obtain imaging evidence of collateral formation by conventional angiography. METHODS AND RESULTS: Peripheral blood CD34+ and CD34- cells were isolated from patients with critical limb ischemia. PBS, CD34- cells, or CD34+ cells were intramyocardially transplanted after ligating LAD of nude rats. Coronary angiography of ex vivo beating hearts 5 and 28 days after the treatment was performed using the third generation synchrotron radiation microangiography (SRM), which has potential to visualize vessels as small as 20 microm in diameter. The SRM was performed pre and post sodium nitroprusside (SNP) to examine vascular physiology at each time point. Diameter of most collateral vessels was 20 to 120 microm, apparently invisible size in conventional angiography. Rentrop scores at day 28 pre and post SNP were significantly greater in CD34+ cell group than other groups (P<0.01). To quantify the extent of collateral formation, angiographic microvessel density (AMVD) in the occluded LAD area was analyzed. AMVD on day 28 post SNP, not pre SNP, was significantly augmented in CD34+ cell group than other groups (P<0.05). AMVD post SNP closely correlated with histological capillary density (R=0.82, P<0.0001). CONCLUSIONS: The SRM, capable of visualizing microvessels, may be useful for morphometric and physiological evaluation of coronary collateral formation by SCTx. The novel imaging system may be an essential tool in future preclinical/translational research of stem cell biology.
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Angiografía Coronaria/métodos , Vasos Coronarios/patología , Infarto del Miocardio/diagnóstico por imagen , Revascularización Miocárdica/métodos , Neovascularización Fisiológica , Trasplante de Células Madre de Sangre Periférica , Sincrotrones , Anciano , Animales , Procedimientos Quirúrgicos Cardíacos , Circulación Colateral , Circulación Coronaria , Vasos Coronarios/fisiopatología , Enfermedad Crítica , Modelos Animales de Enfermedad , Células Endoteliales/patología , Extremidades/irrigación sanguínea , Femenino , Humanos , Isquemia/patología , Masculino , Microcirculación/diagnóstico por imagen , Microcirculación/fisiopatología , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/cirugía , Ratas , Ratas Desnudas , Células Madre/patología , Factores de Tiempo , Trasplante HeterólogoRESUMEN
BACKGROUND: We compared the therapeutic potential of purified mobilized human CD34+ cells with that of mobilized total mononuclear cells (tMNCs) for the preservation/recovery of myocardial tissue integrity and function after myocardial infarction (MI). METHODS AND RESULTS: CD34+ cells were purified from peripheral blood tMNCs of healthy volunteers by magnetic cell sorting after a 5-day administration of granulocyte colony-stimulating factor. Phosphate-buffered saline (PBS), 5x10(5) CD34+ cells/kg, 5x10(5) tMNCs/kg (low-dose MNCs [loMNCs]), or a higher dose of tMNCs (hiMNCs) containing 5x10(5) CD34+ cells/kg was transplanted intramyocardially 10 minutes after the induction of MI in athymic nude rats. Hematoxylin and eosin staining revealed that moderate to severe hemorrhagic MI on day 3 was more frequent in the hiMNC group than in the PBS and CD34+ cell groups. Immunostaining for human-specific CD45 revealed abundant distribution of hematopoietic/inflammatory cells derived from transplanted cells in the ischemic myocardium of the hiMNC group. Capillary density on day 28 was significantly greater in the CD34+ cell group (721.1+/-19.9 per 1 mm2) than in the PBS, loMNC, and hiMNC groups (384.7+/-11.0, 372.5+/-14.1, and 497.5+/-24.0 per 1 mm2) (P<0.01). Percent fibrosis area on day 28 was less in the CD34(+) cell group (15.6+/-0.9%) than in the PBS, loMNC, and hiMNC groups (26.3+/-1.2%, 27.5+/-1.8%, and 22.2+/-1.8%) (P<0.05). Echocardiographic fractional shortening on day 28 was significantly higher in the CD34+ cell group (30.3+/-0.9%) than in the PBS, loMNC, and hiMNC groups (22.7+/-1.5%, 23.4+/-1.1%, and 24.9+/-1.7%; P<0.05). Echocardiographic regional wall motion score was better preserved in the CD34+ cell group (21.8+/-0.5) than in the PBS, loMNC, and hiMNC groups (25.4+/-0.4, 24.9+/-0.4, and 24.1+/-0.6; P<0.05). CONCLUSIONS: CD34+ cells exhibit superior efficacy for preserving myocardial integrity and function after MI than unselected circulating MNCs.
Asunto(s)
Antígenos CD34/metabolismo , Monocitos/metabolismo , Monocitos/trasplante , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/cirugía , Neovascularización Fisiológica , Animales , Diferenciación Celular , Ecocardiografía , Femenino , Hemorragia/etiología , Humanos , Monocitos/patología , Infarto del Miocardio/complicaciones , Infarto del Miocardio/patología , Miocardio/patología , Periodo Posoperatorio , Ratas , Ratas Desnudas , Ratas Sprague-Dawley , Índice de Severidad de la Enfermedad , Factores de Tiempo , Trasplante Heterólogo , Función Ventricular Izquierda , Remodelación VentricularRESUMEN
Failures in fracture healing are mainly caused by a lack of vascularization. Adult human circulating CD34+ cells, an endothelial/hematopoietic progenitor-enriched cell population, have been reported to differentiate into osteoblasts in vitro; however, the therapeutic potential of CD34+ cells for fracture healing is still unclear. Therefore, we performed a series of experiments to test our hypothesis that functional fracture healing is supported by vasculogenesis and osteogenesis via regenerative plasticity of CD34+ cells. Peripheral blood CD34+ cells, isolated from total mononuclear cells of adult human volunteers, showed gene expression of osteocalcin in 4 of 20 freshly isolated cells by single cell reverse transcriptase-polymerase chain reaction analysis. Phosphate-buffered saline, mononuclear cells, or CD34+ cells were intravenously transplanted after producing nonhealing femoral fractures in nude rats. Reverse transcriptase-polymerase chain reaction and immunohistochemical staining at the peri-fracture site demonstrated molecular and histological expression of human-specific markers for endothelial cells and osteoblasts at week 2. Functional bone healing assessed by biomechanical as well as radiological and histological examinations was significantly enhanced by CD34+ cell transplantation compared with the other groups. Our data suggest circulating human CD34+ cells have therapeutic potential to promote an environment conducive to neovascularization and osteogenesis in damaged skeletal tissue, allowing the complete healing of fractures.