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1.
Neurotrauma Rep ; 4(1): 447-457, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37475977

RESUMEN

The Extended Glasgow Outcome Scale (GOSE) is accepted as the primary outcome measure in registrational studies for traumatic brain injury (TBI). The Disability Rating Scale (DRS) is used to assess functional progress from initial acute injury, through rehabilitation and reintegration into the community and life. For these reasons, the DRS is an alternative measure for assessing meaningful global outcomes in chronic TBI. The objective of this study was to determine the minimally clinically important difference (MCID) for the DRS in chronic TBI, by determining the magnitude of DRS change associated with the MCID for the GOSE of 1 point. This study is a retrospective analysis of the multi-center, prospective, longitudinal, Traumatic Brain Injury Model Systems National Database of persons with outcomes at 1, 2, and 5 years and every 5 years thereafter post-injury. Spearman's correlations for dynamic and static relationships between the DRS and GOSE were significant. For the 1-point MCID for the GOSE, the dynamic MCID estimate for the DRS of a -0.68-point change was calculated as the mean DRS change associated with the difference of the GOSE score between year 1 and year 2 (score range, 3-8), using all persons in the study (n = 11,102), whereas the exploratory static MCID estimate for the DRS of -1.28 points was calculated from the slope of the best-fit line between the DRS and GOSE at year 1 follow-up (score range, 3-8; n = 13,415). The final MCID for the DRS was calculated by using the triangulation method (i.e., the arithmetic mean of the dynamic and exploratory static MCID estimates), which resulted in a -1.0-point change. The significant correlation between the DRS and GOSE has allowed for the establishment of a -1.0-point MCID for the DRS, which supports the use of the DRS as an alternative primary outcome measure for chronic TBI research studies, including clinical trials.

2.
Expert Rev Neurother ; 21(9): 1051-1058, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34402352

RESUMEN

OBJECTIVE: To determine minimally clinically important differences (MCIDs) for Disability Rating Scale (DRS), Fugl-Meyer Upper Extremity Subscale (FM-UE), Fugl-Meyer Lower Extremity Subscale (FM-LE), and Fugl-Meyer Motor Scale (FMMS) in patients with chronic motor deficits secondary to traumatic brain injury (TBI). METHODS: Retrospective analysis from the 1-year, double-blind, randomized, surgical sham-controlled, Phase 2 STEMTRA trial (NCT02416492), in which patients with chronic motor deficits secondary to TBI (N = 61) underwent intracerebral stereotactic implantation of modified bone marrow-derived mesenchymal stromal (SB623) cells. MCIDs for DRS, FM-UE, FM-LE, and FMMS were triangulated with distribution-based, anchor-based, and Delphi panel estimates. RESULTS: Triangulated MCIDs were: 1) -1.5 points for the Disability Rating Scale; 2) 6.2 points for the Fugl-Meyer Upper Extremity Subscale; 3) 3.2 points for the Fugl-Meyer Lower Extremity Subscale; and 4) 8.4 points for the Fugl-Meyer Motor Scale. CONCLUSIONS: For the first time in the setting of patients with chronic motor deficits secondary to TBI, this study reports triangulated MCIDs for: 1) DRS, a measure of global outcome; and 2) Fugl-Meyer Scales, measures of motor impairment. These findings guide the use of DRS and Fugl-Meyer Scales in the assessment of global disability outcome and motor impairment in future TBI clinical trials.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Lesiones Traumáticas del Encéfalo/complicaciones , Evaluación de la Discapacidad , Humanos , Evaluación de Resultado en la Atención de Salud , Recuperación de la Función , Estudios Retrospectivos
3.
Aesthet Surg J Open Forum ; 3(3): ojab019, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34195612

RESUMEN

Elastin is the main component of elastic fibers, which provide stretch, recoil, and elasticity to the skin. Normal levels of elastic fiber production, organization, and integration with other cutaneous extracellular matrix proteins, proteoglycans, and glycosaminoglycans are integral to maintaining healthy skin structure, function, and youthful appearance. Although elastin has very low turnover, its production decreases after individuals reach maturity and it is susceptible to damage from many factors. With advancing age and exposure to environmental insults, elastic fibers degrade. This degradation contributes to the loss of the skin's structural integrity; combined with subcutaneous fat loss, this results in looser, sagging skin, causing undesirable changes in appearance. The most dramatic changes occur in chronically sun-exposed skin, which displays sharply altered amounts and arrangements of cutaneous elastic fibers, decreased fine elastic fibers in the superficial dermis connecting to the epidermis, and replacement of the normal collagen-rich superficial dermis with abnormal clumps of solar elastosis material. Disruption of elastic fiber networks also leads to undesirable characteristics in wound healing, and the worsening structure and appearance of scars and stretch marks. Identifying ways to replenish elastin and elastic fibers should improve the skin's appearance, texture, resiliency, and wound-healing capabilities. However, few therapies are capable of repairing elastic fibers or substantially reorganizing the elastin/microfibril network. This review describes the clinical relevance of elastin in the context of the structure and function of healthy and aging skin, wound healing, and scars and introduces new approaches being developed to target elastin production and elastic fiber formation.

4.
Neurology ; 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397772

RESUMEN

OBJECTIVE: To determine if chronic motor deficits secondary to traumatic brain injury (TBI) can be improved by implantation of allogeneic modified bone marrow-derived mesenchymal stromal/stem cells (SB623). METHODS: This 6-month interim analysis of the 1-year double-blind, randomized, surgical sham-controlled, phase 2 STEMTRA trial (NCT02416492) evaluated safety and efficacy of the stereotactic intracranial implantation of SB623 in patients with stable chronic motor deficits secondary to TBI. Patients in this multi-center trial (N = 63) underwent randomization in a 1:1:1:1 ratio to 2.5 × 106, 5.0 × 106, 10 × 106 SB623 cells or control. Safety was assessed in patients who underwent surgery (N = 61), and efficacy in the modified intent-to-treat population of randomized patients who underwent surgery (N = 61; SB623 = 46, control = 15). RESULTS: The primary efficacy endpoint of significant improvement from baseline of Fugl-Meyer Motor Scale score at 6 months for SB623-treated patients was achieved. SB623-treated patients improved by (LS mean [SE]) +8.3 (1.4) vs +2.3 (2.5) for control at 6 months, the LS mean difference was 6.0 (95% CI: 0.3-11.8); p = 0.040. Secondary efficacy endpoints improved from baseline, but were not statistically significant vs control at 6 months. There were no dose-limiting toxicities or deaths, and 100% of SB623-treated patients experienced treatment-emergent adverse events vs 93.3% of control patients (p = 0.25). CONCLUSIONS: SB623 cell implantation appeared to be safe and well tolerated, and patients implanted with SB623 experienced significant improvement from baseline motor status at 6 months compared to controls. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that implantation of SB623 was well tolerated and associated with improvement in motor status.

5.
J Neurosurg ; : 1-11, 2018 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-30497166

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the safety and clinical outcomes associated with stereotactic surgical implantation of modified bone marrow-derived mesenchymal stem cells (SB623) in patients with stable chronic ischemic stroke. METHODS: This was a 2-year, open-label, single-arm, phase 1/2a study; the selected patients had chronic motor deficits between 6 and 60 months after nonhemorrhagic stroke. SB623 cells were administered to the target sites surrounding the subcortical stroke region using MRI stereotactic image guidance. RESULTS: A total of 18 patients were treated with SB623 cells. All experienced at least 1 treatment-emergent adverse event (TEAE). No patients withdrew due to adverse events, and there were no dose-limiting toxicities or deaths. The most frequent TEAE was headache related to the surgical procedure (88.9%). Seven patients experienced 9 serious adverse events, which resolved without sequelae. In 16 patients who completed 24 months of treatment, statistically significant improvements from baseline (mean) at 24 months were reported for the European Stroke Scale (ESS) score, 5.7 (95% CI 1.4-10.1, p < 0.05); National Institutes of Health Stroke Scale (NIHSS) score, -2.1 (95% CI -3.3 to -1.0, p < 0.01), Fugl-Meyer (F-M) total score, 19.4 (95% CI 9.9-29.0, p < 0.01); and F-M motor scale score, 10.4 (95% CI 4.0-16.7, p < 0.01). Measures of efficacy reached plateau by 12 months with no decline thereafter. There were no statistically significant changes in the modified Rankin Scale score. The size of transient lesions detected by T2-weighted FLAIR imaging in the ipsilateral cortex at weeks 1-2 postimplantation significantly correlated with improvement in ESS (0.619, p < 0.05) and NIHSS (-0.735, p < 0.01) scores at 24 months. CONCLUSIONS: In this completed 2-year phase 1/2a study, implantation of SB623 cells in patients with stable chronic stroke was safe and was accompanied by improvements in clinical outcomes.Clinical trial registration no.: NCT01287936 (clinicaltrials.gov).

6.
Growth Factors ; 36(1-2): 58-68, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-30035654

RESUMEN

Ryk is a member of the receptor tyrosine kinase (RTK) family of proteins that control and regulate cellular processes. It is distinguished by binding Wnt ligands and having no detectable intrinsic protein tyrosine kinase activity suggesting Ryk is a pseudokinase. Here, we show an essential role for Ryk in directing morphogenetic events required for normal cardiac development through the examination of Ryk-deficient mice. We employed vascular corrosion casting, vascular perfusion with contrast dye, and immunohistochemistry to characterize cardiovascular and pharyngeal defects in Ryk-/- embryos. Ryk-/- mice exhibit a variety of malformations of the heart and outflow tract that resemble human congenital heart defects. This included stenosis and interruption of the aortic arch, ventriculoarterial malalignment, ventricular septal defects and abnormal pharyngeal arch artery remodelling. This study therefore defines a key intersection between a subset of growth factor receptors involved in planar cell polarity signalling, the Wnt family and mammalian cardiovascular development.


Asunto(s)
Cardiopatías Congénitas/etiología , Faringe/anomalías , Proteínas Tirosina Quinasas Receptoras/fisiología , Proteínas Wnt/metabolismo , Animales , Aorta Torácica/anomalías , Femenino , Ratones , Morfogénesis , Embarazo
8.
Cell Med ; 8(3): 79-85, 2016 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-28003933

RESUMEN

Clinical applications of mesenchymal stromal cells (MSCs) require the manufacture of large cell lots, which involves multiple passages for cell expansion and sometimes genetic modification. MSCs from various sources, including bone marrow (BM), exhibit high donor-to-donor variability in their growth characteristics. This can lead to unpredictable manufacturing outcomes with respect to success or failure of individual lots. Early determination of lot success has the potential to reduce the cost and improve the efficiency of the MSC manufacturing process. However, methods that effectively predict lot growth potential early in the manufacturing process are currently lacking. Here we report that the growth potential of an MSC lot can be predicted a few days after BM plating based on α-smooth muscle actin (αSMA) protein expression in large colony-forming unit-fibroblast (CFU-f) colonies. The proposed prediction method could be a useful tool to prospectively determine MSC lot success or failure.

9.
Stroke ; 47(7): 1817-24, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27256670

RESUMEN

BACKGROUND AND PURPOSE: Preclinical data suggest that cell-based therapies have the potential to improve stroke outcomes. METHODS: Eighteen patients with stable, chronic stroke were enrolled in a 2-year, open-label, single-arm study to evaluate the safety and clinical outcomes of surgical transplantation of modified bone marrow-derived mesenchymal stem cells (SB623). RESULTS: All patients in the safety population (N=18) experienced at least 1 treatment-emergent adverse event. Six patients experienced 6 serious treatment-emergent adverse events; 2 were probably or definitely related to surgical procedure; none were related to cell treatment. All serious treatment-emergent adverse events resolved without sequelae. There were no dose-limiting toxicities or deaths. Sixteen patients completed 12 months of follow-up at the time of this analysis. Significant improvement from baseline (mean) was reported for: (1) European Stroke Scale: mean increase 6.88 (95% confidence interval, 3.5-10.3; P<0.001), (2) National Institutes of Health Stroke Scale: mean decrease 2.00 (95% confidence interval, -2.7 to -1.3; P<0.001), (3) Fugl-Meyer total score: mean increase 19.20 (95% confidence interval, 11.4-27.0; P<0.001), and (4) Fugl-Meyer motor function total score: mean increase 11.40 (95% confidence interval, 4.6-18.2; P<0.001). No changes were observed in modified Rankin Scale. The area of magnetic resonance T2 fluid-attenuated inversion recovery signal change in the ipsilateral cortex 1 week after implantation significantly correlated with clinical improvement at 12 months (P<0.001 for European Stroke Scale). CONCLUSIONS: In this interim report, SB623 cells were safe and associated with improvement in clinical outcome end points at 12 months. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01287936.


Asunto(s)
Trasplante de Médula Ósea/métodos , Trasplante de Células Madre Mesenquimatosas/métodos , Accidente Cerebrovascular/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
10.
Stem Cells Dev ; 24(14): 1623-34, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25873141

RESUMEN

Beneficial effects of intracerebral transplantation of mesenchymal stromal cells (MSC) and their derivatives are believed to be mediated mostly by factors produced by engrafted cells. However, the mesenchymal cell engraftment rate is low, and the majority of grafted cells disappear within a short post-transplantation period. Here, we hypothesize that dying transplanted cells can affect surrounding tissues by releasing their active intracellular components. To elucidate the type, amounts, and potency of these putative intracellular factors, freeze/thaw extracts of MSC or their derivatives were tested in enzyme-linked immunosorbent assays and bioassays. We found that fibroblast growth factor (FGF)2 and FGF1, but not vascular endothelial growth factor and monocyte chemoattractant protein 1 levels were high in extracts despite being low in conditioned media. Extracts induced concentration-dependent proliferation of rat cortical neural progenitor cells and human umbilical vein endothelial cells; these proliferative responses were specifically blocked by FGF2-neutralizing antibody. In the neuropoiesis assay with rat cortical cells, both MSC extracts and killed cells induced expression of nestin, but not astrocyte differentiation. However, suspensions of killed cells strongly potentiated the astrogenic effects of live MSC. In transplantation-relevant MSC injury models (peripheral blood cell-mediated cytotoxicity and high cell density plating), MSC death coincided with the release of intracellular FGF2. The data showed that MSC contain a major depot of active FGF2 that is released upon cell injury and is capable of acutely stimulating neuropoiesis and angiogenesis. We therefore propose that both dying and surviving grafted MSC contribute to tissue regeneration.


Asunto(s)
Extractos Celulares/farmacología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Neurogénesis/efectos de los fármacos , Animales , Encéfalo/citología , Diferenciación Celular , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CCL2/metabolismo , Medios de Cultivo Condicionados/farmacología , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Células-Madre Neurales/metabolismo , Ratas , Factor A de Crecimiento Endotelial Vascular/metabolismo
12.
J Periodontol ; 85(4): e57-64, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24070401

RESUMEN

BACKGROUND: Generation of site-appropriate tissue in the oral cavity includes the restoration of the correct anatomic type, amount, and distribution of the tissue. This study is a post hoc analysis of data collected during previously published results from two randomized clinical trials of a living cellular sheet (LCS; allogenic cultured keratinocytes and fibroblasts in bovine collagen) versus a free gingival graft (FGG), evaluating their ability to augment keratinized tissue or gingiva. METHODS: Post hoc histologic and clinical (photographic) comparisons of the outcomes of treatment were performed on histologic and photographic data gathered in the two randomized clinical trials. RESULTS: Histologic findings showed that LCS-treated sites resembled gingiva rather than alveolar mucosa. Photographic analysis indicated that LCS treatment resulted in more site-appropriate tissue than FGG in terms of tissue color, with adjacent untreated tissue, absence of scar formation or keloid-like appearance, and mucogingival junction alignment. CONCLUSION: Treatment of mucogingival defects with LCS resulted in the generation of tissue that is more site appropriate than tissue transplanted from the palate.


Asunto(s)
Aloinjertos/trasplante , Colágeno , Fibroblastos/trasplante , Encía/trasplante , Enfermedades de las Encías/cirugía , Queratinocitos/trasplante , Andamios del Tejido , Aloinjertos/patología , Animales , Autoinjertos/trasplante , Biopsia/métodos , Bovinos , Cicatriz/prevención & control , Color , Células Epiteliales/patología , Estética Dental , Fibroblastos/patología , Estudios de Seguimiento , Encía/patología , Enfermedades de las Encías/patología , Humanos , Queloide/prevención & control , Queratinocitos/patología , Queratinas , Mucosa Bucal/patología , Fotograbar/métodos , Ingeniería de Tejidos/métodos , Resultado del Tratamiento
13.
Int J Oral Maxillofac Implants ; 28(6): e424-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24278955

RESUMEN

Oral soft tissue plays an important role in the structure and function of the oral cavity by protecting against exogenous substances, pathogens, and mechanical stresses. Repair of oral soft tissue defects that arise as a result of disease, trauma, or congenital abnormalities is often accomplished via transplantation or transfer of autologous mucosal tissue. However, this method of treatment can be complicated by the relatively small amount of autologous mucosal tissue that is available, as well as by the morbidity that may be associated with the donor site and patient reluctance to have oral (eg, palatal) surgery. To circumvent these problems, clinicians have turned to the fields of tissue engineering and regenerative medicine to develop acellular and cellular strategies for regenerating oral soft tissue. This review focuses on the efficacy and safety of cell-based investigational approaches to the regeneration of oral soft tissue.


Asunto(s)
Trasplante de Células/métodos , Enfermedades de la Boca/terapia , Ingeniería de Tejidos/métodos , Dermis Acelular , Técnicas de Cultivo de Célula , Tejido Conectivo/trasplante , Fibroblastos/trasplante , Encía/trasplante , Humanos , Mucosa Bucal/trasplante , Ensayos Clínicos Controlados Aleatorios como Asunto , Medicina Regenerativa/métodos , Trasplante de Piel/métodos
14.
J Periodontol ; 82(10): 1414-23, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21513473

RESUMEN

BACKGROUND: The standard of care for increasing keratinized gingiva adjacent to teeth that do not require root coverage is the free gingival graft (FGG). A pilot study indicated that the use of a living cellular construct (LCC) could be effective in this clinical scenario. METHODS: A pivotal, multicenter, randomized, within-patient, controlled, open-label trial was conducted (N = 96 patients). After removing the mucosa and keratinized gingiva from the test site, either an LCC or FGG was applied. The primary efficacy endpoint was the ability of the LCC to regenerate ≥2 mm keratinized gingiva at 6 months. Secondary measures were the same color and texture as the adjacent tissue, a 1-mm width of keratinized gingiva at 6 months, patient treatment preference, surgical site sensitivity at 1 week, and patient-reported pain after 3 days. Safety was assessed by reports of adverse events. RESULTS: At 6 months, the LCC regenerated ≥2 mm of keratinized gingiva in 95.3% of patients (81 of 85 patients; P <0.001 versus a 50% predefined standard). As expected, the FGG generated more keratinized gingiva than the LCC (4.57 ± 1.0 mm versus 3.2 ± 1.1 mm, respectively). The gingiva regenerated with the LCC matched the color and texture of the adjacent gingiva. All patients achieved ≥1 mm keratinized gingiva with the LCC treatment by 6 months, and more patients preferred treatment with the LCC than with the FGG. No difference in sensitivity or pain was noted between the treatments. The treatments were well tolerated, and reported adverse events were typical for this type of periodontal surgery. CONCLUSION: The use of an LCC may provide a safe and effective therapy for augmenting the zone of keratinized gingiva.


Asunto(s)
Recesión Gingival/cirugía , Gingivoplastia/métodos , Queratinocitos/trasplante , Regeneración , Ingeniería de Tejidos/métodos , Adulto , Anciano , Colágeno , Femenino , Fibroblastos/trasplante , Estudios de Seguimiento , Encía/metabolismo , Encía/fisiología , Encía/trasplante , Sustancias de Crecimiento/biosíntesis , Humanos , Análisis de Intención de Tratar , Queratinocitos/metabolismo , Masculino , Persona de Mediana Edad , Prioridad del Paciente , Seguridad del Paciente , Pigmentación , Estudios Prospectivos , Andamios del Tejido , Adulto Joven
15.
Regen Med ; 5(6): 853-4, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21082885
16.
Aesthetic Plast Surg ; 34(3): 350-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20336456

RESUMEN

BACKGROUND: Recurrent ptosis is a common sequel of mastopexy. The use of mesh as an adjunct to the double-skin technique was developed to reduce the incidence of recurrent ptosis. The optimal mesh needs to strike the right balance between persistence, inflammation, biocompatibility, and incorporation without interfering with mammography or presenting a long-term infection risk. This study investigated the ability of a biologic tissue matrix, FortaPerm, to achieve these goals. METHODS: Women undergoing mastopexy were enrolled in this prospective observational study. The study participants were evaluated at multiple time points for 5 years. Efficacy was assessed primarily by photographic evaluation and secondarily by mammography, patient and physician global assessments, and patient pain assessments. RESULTS: Five women ages 17-41 years were enrolled in this study. At 12 months, 80% of the patients (4/5), and at 5 years, 66% of the patients (2/3) had no asymmetry or ptosis. Mammographic evaluation of the breasts was not affected by the presence of the FortaPerm, and there were no abnormal findings. In two patients, FortaPerm was associated with bilateral seromas associated with extrusion of small amounts of the FortaPerm material in the absence of surrounding inflammation. CONCLUSIONS: FortaPerm achieved excellent initial aesthetic outcomes and long-term maintenance of the breast position with no evidence of ptosis 5 years postoperatively for a majority of the patients. FortaPerm did not interfere with mammography, presented no long-term safety concerns, and produced satisfactory results for all patients relative to appearance of the scar as well as shape and firmness of the breasts.


Asunto(s)
Mamoplastia/métodos , Mallas Quirúrgicas , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
18.
Dev Biol ; 255(1): 77-98, 2003 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12618135

RESUMEN

Peripheral nerves and blood vessels have similar patterns in quail forelimb development. Usually, nerves extend adjacent to existing blood vessels, but in a few cases, vessels follow nerves. Nerves have been proposed to follow vascular smooth muscle, endothelium, or their basal laminae. Focusing on the major axial blood vessels and nerves, we found that when nerves grow into forelimbs at E3.5-E5, vascular smooth muscle was not detectable by smooth muscle actin immunoreactivity. Additionally, transmission electron microscopy at E5.5 confirmed that early blood vessels lacked smooth muscle and showed that the endothelial cell layer lacks a basal lamina, and we did not observe physical contact between peripheral nerves and these endothelial cells. To test more generally whether lack of nerves affected blood vessel patterns, forelimb-level neural tube ablations were performed at E2 to produce aneural limbs; these had completely normal vascular patterns up to at least E10. To test more generally whether vascular perturbation affected nerve patterns, VEGF(165), VEGF(121), Ang-1, and soluble Flt-1/Fc proteins singly and in combination were focally introduced via beads implanted into E4.5 forelimbs. These produced significant alterations to the vascular patterns, which included the formation of neo-vessels and the creation of ectopic avascular spaces at E6, but in both under- and overvascularized forelimbs, the peripheral nerve pattern was normal. The spatial distribution of semaphorin3A protein immunoreactivity was consistent with a negative regulation of neural and/or vascular patterning. Semaphorin3A bead implantations into E4.5 forelimbs caused failure of nerves and blood vessels to form and to deviate away from the bead. Conversely, semaphorin3A antibody bead implantation was associated with a local increase in capillary formation. Furthermore, neural tube electroporation at E2 with a construct for the soluble form of neuropilin-1 caused vascular malformations and hemorrhage as well as altered nerve trajectories and peripheral nerve defasciculation at E5-E6. These results suggest that neurovascular congruency does not arise from interdependence between peripheral nerves and blood vessels, but supports the hypothesis that it arises by a shared patterning mechanism that utilizes semaphorin3A.


Asunto(s)
Vasos Sanguíneos/embriología , Tipificación del Cuerpo , Embrión no Mamífero/irrigación sanguínea , Miembro Anterior/irrigación sanguínea , Miembro Anterior/embriología , Neuropilina-1/metabolismo , Semaforina-3A/metabolismo , Angiotensina II/farmacología , Animales , Vasos Sanguíneos/anomalías , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/ultraestructura , Células Cultivadas , Cricetinae , Técnicas de Cultivo , Embrión no Mamífero/ultraestructura , Factores de Crecimiento Endotelial/farmacología , Proteínas de la Matriz Extracelular/farmacología , Miembro Anterior/efectos de los fármacos , Miembro Anterior/inervación , Miembro Anterior/ultraestructura , Péptidos y Proteínas de Señalización Intercelular/farmacología , Linfocinas/farmacología , Fragmentos de Péptidos/farmacología , Nervios Periféricos/irrigación sanguínea , Nervios Periféricos/embriología , Nervios Periféricos/ultraestructura , Codorniz , Semaforina-3A/farmacología , Factor A de Crecimiento Endotelial Vascular , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
19.
Dev Biol ; 249(2): 300-20, 2002 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-12221008

RESUMEN

Peripheral nerve and vascular patterns are congruent in the adult vertebrate, but this has been disputed in vertebrate embryos. The most detailed of these studies have used the avian forelimb as a model system, yet neurovascular anatomical relationships and critical vascular remodeling events remain inadequately characterized in this model. To address this, we have used a combination of intravascular marker injection, multilabel fluorescent stereomicroscopy, and confocal microscopy to analyze the spatiotemporal relationships between peripheral nerves and blood vessels in the forelimb of 818 quail embryos from E2 (HH13) to E15 (HH41). We find that the neurovascular anatomical relationships established during development are highly stereotypic and congruent. Blood vessels typically arise before their corresponding nerves, but there are several critical exceptions to this rule. The vascular pattern is extensively remodeled from the earliest stage examined (E2; HH13), whereas the peripheral nerves, the first of which enter the forelimb at E3.5-E4 (HH21-HH24), have a progressively unfolding pattern that, once formed, remains essentially unchanged. The adult neurovascular pattern is not established until E8 (HH34). Peripheral nerves are always found to track close and parallel to the vasculature. As they track distally, peripheral nerves always lie on the side of the vasculature away from the center of the forelimb. Neurovascular patterns have a hierarchy of congruence that is highest in the dorsoventral plane, followed by the anteroposterior, and lastly the proximodistal planes.


Asunto(s)
Vasos Sanguíneos/embriología , Tipificación del Cuerpo/fisiología , Coturnix/embriología , Embrión no Mamífero/fisiología , Miembro Anterior/embriología , Sistema Nervioso Periférico/embriología , Alas de Animales/irrigación sanguínea , Animales , Miembro Anterior/irrigación sanguínea , Mutación , Alas de Animales/embriología , Alas de Animales/inervación
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