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1.
Adv Wound Care (New Rochelle) ; 13(4): 155-166, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38299969

RESUMEN

Objective: Given the significant economic, health care, and personal burden of acute and chronic wounds, we investigated the dose dependent wound healing mechanisms of two Avena sativa derived compounds: avenanthramide (AVN) and ß-Glucan. Approach: We utilized a splinted excisional wound model that mimics human-like wound healing and performed subcutaneous AVN and ß-Glucan injections in 15-week-old C57BL/6 mice. Histologic and immunohistochemical analysis was performed on the explanted scar tissue to assess changes in collagen architecture and cellular responses. Results: AVN and ß-Glucan treatment provided therapeutic benefits at a 1% dose by weight in a phosphate-buffered saline vehicle, including accelerated healing time, beneficial cellular recruitment, and improved tissue architecture of healed scars. One percent AVN treatment promoted an extracellular matrix (ECM) architecture similar to unwounded skin, with shorter, more randomly aligned collagen fibers and reduced inflammatory cell presence in the healed tissue. One percent ß-Glucan treatment promoted a tissue architecture characterized by long, thick bundles of collagen with increased blood vessel density. Innovation: AVN and ß-Glucan have previously shown promise in promoting wound healing, although the therapeutic efficacies and mechanisms of these bioactive compounds remain incompletely understood. Furthermore, the healed ECM architecture of these wounds has not been characterized. Conclusions: AVN and ß-Glucan accelerated wound closure compared to controls through distinct mechanisms. AVN-treated scars displayed a more regenerative tissue architecture with reduced inflammatory cell recruitment, while ß-Glucan demonstrated increased angiogenesis with more highly aligned tissue architecture more indicative of fibrosis. A deeper understanding of the mechanisms driving healing in these two naturally derived therapeutics will be important for translation to human use.


Asunto(s)
Cicatriz , beta-Glucanos , ortoaminobenzoatos , Animales , Ratones , beta-Glucanos/farmacología , Colágeno , Ratones Endogámicos C57BL , Cicatrización de Heridas
2.
Int Wound J ; 20(10): 4083-4096, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37402533

RESUMEN

A novel autologous heterogeneous skin construct (AHSC) was previously shown to be effective versus standard of care (SOC) treatment in facilitating complete wound healing of Wagner 1 diabetic foot ulcers in an interim analysis of 50 patients previously published. We now report the final analysis of 100 patients (50 per group), which further supports the interim analysis findings. Forty-five subjects in the AHSC treatment group received only one application of the autologous heterogeneous skin construct, and five received two applications. For the primary endpoint at 12 weeks, there were significantly more diabetic wounds closed in the AHSC treatment group (35/50, 70%) than in the SOC control group (17/50, 34%) (p = 0.00032). A significant difference in percentage area reduction between groups was also demonstrated over 8 weeks (p = 0.009). Forty-nine subjects experienced 148 adverse events: 66 occurred in 21 subjects (42%) in the AHSC treatment group versus 82 in 28 SOC control group subjects (56.0%). Eight subjects were withdrawn due to serious adverse events. Autologous heterogeneous skin construct was shown to be an effective adjunctive therapy for healing Wagner 1 diabetic foot ulcers.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Piel Artificial , Humanos , Pie Diabético/terapia , Cicatrización de Heridas , Piel , Resultado del Tratamiento
3.
Tissue Cell ; 83: 102126, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37295271

RESUMEN

Acute and chronic wounds involving deeper layers of the skin are often not adequately healed by dressings alone and require therapies such as skin grafting, skin substitutes, or growth factors. Here we report the development of an autologous heterogeneous skin construct (AHSC) that aids wound closure. AHSC is manufactured from a piece of healthy full-thickness skin. The manufacturing process creates multicellular segments, which contain endogenous skin cell populations present within hair follicles. These segments are physically optimized for engraftment within the wound bed. The ability of AHSC to facilitate closure of full thickness wounds of the skin was evaluated in a swine model and clinically in 4 patients with wounds of different etiologies. Transcriptional analysis demonstrated high concordance of gene expression between AHSC and native tissues for extracellular matrix and stem cell gene expression panels. Swine wounds demonstrated complete wound epithelialization and mature stable skin by 4 months, with hair follicle development in AHSC-treated wounds evident by 15 weeks. Biomechanical, histomorphological, and compositional analysis of the resultant swine and human skin wound biopsies demonstrated the presence of epidermal and dermal architecture with follicular and glandular structures that are similar to native skin. These data suggest that treatment with AHSC can facilitate wound closure.


Asunto(s)
Piel , Cicatrización de Heridas , Porcinos , Humanos , Animales , Cicatrización de Heridas/genética , Piel/patología , Epidermis/patología , Trasplante de Piel , Folículo Piloso
4.
Plast Reconstr Surg ; 150(5): 1128-1136, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36067479

RESUMEN

BACKGROUND: This randomized controlled trial evaluated the safety and effectiveness of weekly and biweekly applications of dehydrated human amnion and chorion allograft (dHACA) plus standard of care compared to standard of care alone on chronic venous leg ulcers. METHODS: This open-label randomized controlled trial included patients with chronic venous leg ulcers at eight wound care centers across the United States. The primary endpoint was the proportion of healed ulcers at 12 weeks. Secondary endpoints included the proportion of ulcers achieving 40 percent closure at 4 weeks and the incidence of adverse events. RESULTS: Among 101 patients screened for eligibility, 60 were eligible and enrolled. At 12 weeks, significantly more venous leg ulcers healed in the two dHACA-treated groups (75 percent) than in the standard-of-care group (30 percent) ( p = 0.001) even after adjustment for wound area ( p = 0.002), with an odds ratio of 8.7 (95 percent CI, 2.2 to 33.6). There were no significant differences in the proportion of wounds with percentage area reduction greater than or equal to 40 percent at 4 weeks among all groups. The adverse event rate was 63.5 percent. Among the 38 adverse events, none were graft or procedure related, and all were resolved with appropriate treatment. CONCLUSIONS: dHACA and standard of care, either applied weekly or biweekly, significantly healed more venous leg ulcers than standard of care alone, suggesting that the use of aseptically processed dHACA is advantageous and a safe and effective treatment option in the healing of chronic venous leg ulcers. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.


Asunto(s)
Úlcera de la Pierna , Úlcera Varicosa , Humanos , Amnios , Úlcera , Úlcera Varicosa/cirugía , Corion/trasplante , Cicatrización de Heridas
5.
Int Wound J ; 19(4): 811-825, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34469077

RESUMEN

This study assesses the impact of a processed microvascular tissue (PMVT) allograft on wound closure and healing in a prospective, single-blinded, multi-centre, randomised controlled clinical trial of 100 subjects with Wagner Grade 1 and 2 chronic neuropathic diabetic foot ulcerations. In addition to standard wound care, including standardised offloading, the treatment arm received PMVT while the control arm received a collagen alginate dressing. The primary endpoint was complete wound closure at 12 weeks. Secondary endpoints assessed on all subjects were percent wound area reduction, time to healing, and local neuropathy. Novel exploratory sub-studies were conducted for wound area perfusion and changes in regional neuropathy. Weekly application of PMVT resulted in increased complete wound closure at 12 weeks (74% vs 38%; P = .0003), greater percent wound area reduction from weeks four through 12 (76% vs 24%; P = .009), decreased time to healing (54 days vs 64 days; P = .009), and improved local neuropathy (118% vs 11%; P = .028) compared with the control arm. Enhanced perfusion and improved regional neuropathy were demonstrated in the sub-studies. In conclusion, this study demonstrated increased complete healing with PMVT and supports its use in treating non-healing DFUs. The observed benefit of PMVT on the exploratory regional neuropathy and perfusion endpoints warrants further study.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Aloinjertos , Vendajes , Pie Diabético/cirugía , Humanos , Estudios Prospectivos , Resultado del Tratamiento , Cicatrización de Heridas
6.
Int Wound J ; 19(1): 64-75, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33942506

RESUMEN

We desired to carefully evaluate a novel autologous heterogeneous skin construct in a prospective randomised clinical trial comparing this to a standard-of-care treatment in diabetic foot ulcers (DFUs). This study reports the interim analysis after the first half of the subjects have been analysed. Fifty patients (25 per group) with Wagner 1 ulcers were enrolled at 13 wound centres in the United States. Twenty-three subjects underwent the autologous heterogeneous skin construct harvest and application procedure once; two subjects required two applications due to loss of the first application. The primary endpoint was the proportion of wounds closed at 12 weeks. There were significantly more wounds closed in the treatment group (18/25; 72%) vs controls (8/25; 32%) at 12 weeks. The treatment group achieved significantly greater percent area reduction compared to the control group at every prespecified timepoint of 4, 6, 8, and 12 weeks. Thirty-eight adverse events occurred in 11 subjects (44%) in the treatment group vs 48 in 14 controls (56%), 6 of which required study removal. In the treatment group, there were no serious adverse events related to the index ulcer. Two adverse events (index ulcer cellulitis and bleeding) were possibly related to the autologous heterogeneous skin construct. Data from this planned interim analysis support that application of autologous heterogeneous skin construct may be potentially effective therapy for DFUs and provide supportive data to complete the planned study.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Pie Diabético/cirugía , Humanos , Estudios Prospectivos , Trasplante Autólogo
7.
Am J Clin Nutr ; 112(3): 721-769, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32687145

RESUMEN

BACKGROUND: The US faces remarkable food and nutrition challenges. A new federal effort to strengthen and coordinate nutrition research could rapidly generate the evidence base needed to address these multiple national challenges. However, the relevant characteristics of such an effort have been uncertain. OBJECTIVES: Our aim was to provide an objective, informative summary of 1) the mounting diet-related health burdens facing our nation and corresponding economic, health equity, national security, and sustainability implications; 2) the current federal nutrition research landscape and existing mechanisms for its coordination; 3) the opportunities for and potential impact of new fundamental, clinical, public health, food and agricultural, and translational scientific discoveries; and 4) the various options for further strengthening and coordinating federal nutrition research, including corresponding advantages, disadvantages, and potential executive and legislative considerations. METHODS: We reviewed government and other published documents on federal nutrition research; held various discussions with expert groups, advocacy organizations, and scientific societies; and held in-person or phone meetings with >50 federal staff in executive and legislative roles, as well as with a variety of other stakeholders in academic, industry, and nongovernment organizations. RESULTS: Stark national nutrition challenges were identified. More Americans are sick than are healthy, largely from rising diet-related illnesses. These conditions create tremendous strains on productivity, health care costs, health disparities, government budgets, US economic competitiveness, and military readiness. The coronavirus disease 2019 (COVID-19) outbreak has further laid bare these strains, including food insecurity, major diet-related comorbidities for poor outcomes from COVID-19 such as diabetes, hypertension, and obesity, and insufficient surveillance on and coordination of our food system. More than 10 federal departments and agencies currently invest in critical nutrition research, yet with relatively flat investments over several decades. Coordination also remains suboptimal, documented by multiple governmental reports over 50 years. Greater harmonization and expansion of federal investment in nutrition science, not a silo-ing or rearrangement of existing investments, has tremendous potential to generate new discoveries to improve and sustain the health of all Americans. Two identified key strategies to achieve this were as follows: 1) a new authority for robust cross-governmental coordination of nutrition research and other nutrition-related policy and 2) strengthened authority, investment, and coordination for nutrition research within the NIH. These strategies were found to be complementary, together catalyzing important new science, partnerships, coordination, and returns on investment. Additional complementary actions to accelerate federal nutrition research were identified at the USDA. CONCLUSIONS: The need and opportunities for strengthened federal nutrition research are clear, with specific identified options to help create the new leadership, strategic planning, coordination, and investment the nation requires to address the multiple nutrition-related challenges and grasp the opportunities before us.


Asunto(s)
Infecciones por Coronavirus/complicaciones , Trastornos Nutricionales/complicaciones , Fenómenos Fisiológicos de la Nutrición , Neumonía Viral/complicaciones , Investigación/normas , COVID-19 , Costo de Enfermedad , Costos de la Atención en Salud , Disparidades en Atención de Salud/economía , Humanos , Personal Militar , National Institutes of Health (U.S.)/economía , Trastornos Nutricionales/economía , Trastornos Nutricionales/epidemiología , Pandemias , Estados Unidos/epidemiología , United States Department of Agriculture/economía , United States Dept. of Health and Human Services/economía
8.
N Engl J Med ; 383(2): 120-128, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32437596

RESUMEN

BACKGROUND: Progressive respiratory failure is the primary cause of death in the coronavirus disease 2019 (Covid-19) pandemic. Despite widespread interest in the pathophysiology of the disease, relatively little is known about the associated morphologic and molecular changes in the peripheral lung of patients who die from Covid-19. METHODS: We examined 7 lungs obtained during autopsy from patients who died from Covid-19 and compared them with 7 lungs obtained during autopsy from patients who died from acute respiratory distress syndrome (ARDS) secondary to influenza A(H1N1) infection and 10 age-matched, uninfected control lungs. The lungs were studied with the use of seven-color immunohistochemical analysis, micro-computed tomographic imaging, scanning electron microscopy, corrosion casting, and direct multiplexed measurement of gene expression. RESULTS: In patients who died from Covid-19-associated or influenza-associated respiratory failure, the histologic pattern in the peripheral lung was diffuse alveolar damage with perivascular T-cell infiltration. The lungs from patients with Covid-19 also showed distinctive vascular features, consisting of severe endothelial injury associated with the presence of intracellular virus and disrupted cell membranes. Histologic analysis of pulmonary vessels in patients with Covid-19 showed widespread thrombosis with microangiopathy. Alveolar capillary microthrombi were 9 times as prevalent in patients with Covid-19 as in patients with influenza (P<0.001). In lungs from patients with Covid-19, the amount of new vessel growth - predominantly through a mechanism of intussusceptive angiogenesis - was 2.7 times as high as that in the lungs from patients with influenza (P<0.001). CONCLUSIONS: In our small series, vascular angiogenesis distinguished the pulmonary pathobiology of Covid-19 from that of equally severe influenza virus infection. The universality and clinical implications of our observations require further research to define. (Funded by the National Institutes of Health and others.).


Asunto(s)
Infecciones por Coronavirus/patología , Endotelio Vascular/patología , Neovascularización Patológica , Neumonía Viral/patología , Trombosis/virología , Anciano , Anciano de 80 o más Años , Autopsia , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/mortalidad , Endotelio Vascular/virología , Femenino , Humanos , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/mortalidad , Gripe Humana/patología , Pulmón/patología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/mortalidad , Síndrome de Dificultad Respiratoria/patología , Síndrome de Dificultad Respiratoria/virología , Insuficiencia Respiratoria , SARS-CoV-2
9.
Int Wound J ; 17(5): 1366-1375, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32453512

RESUMEN

Diabetic foot ulcers (DFUs) are a growing burden on patients and health care systems that often require multiple treatments of both conventional and advanced modalities to achieve complete wound closure. A novel autologous homologous skin construct (AHSC) has been developed to treat cutaneous defects with a single topical application, by leveraging the endogenous repair capabilities of the patient's healthy skin. The AHSC's ability to close DFUs with a single treatment was evaluated in an open-label, single-arm feasibility study. Eleven patients with DFUs extending up to tendon, bone, or capsule received a single topical application of AHSC. Closure was documented weekly with high-resolution digital photography and wound planimetry. All 11 DFUs demonstrated successful graft take. Ten DFUs closed within 8 weeks. The median time-to-complete closure was 25 days. The mean percent area reduction for all 11 wounds at 4 weeks was 83%. There were no adverse events related to the AHSC treatment site. This pilot study demonstrated AHSC may be a viable single application topical intervention for DFUs and warrants investigation in larger, controlled studies.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Pie Diabético/tratamiento farmacológico , Estudios de Factibilidad , Humanos , Proyectos Piloto , Estudios Prospectivos , Cicatrización de Heridas
10.
Regen Med ; 15(2): 1313-1328, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32228366

RESUMEN

Aims: Profiling of microvascular tissue allows identification of components that stimulate wound healing. Here we study those elements for biological effect and establish clinical proof-of-concept using a microvascular tissue graft (mVASC®) in chronic refractory wounds. Methods: mVASC was characterized for tissue fragments and protein composition, evaluated for angiogenic potential in preclinical models, and applied clinically to a series of nonhealing wounds with compromised vascularity of different etiologies. Results: mVASC increased endothelial cell migration in vitro and angiogenesis in mouse ingrowth and hindlimb ischemia models. Clinically, mVASC stimulated wound neovascularization, granulation and epithelialization, and complete and durable healing. Conclusion: Microvascular tissue contains elements relevant to tissue repair and can be clinically applied to enable or accelerate the closure of challenging wounds.


Asunto(s)
Endotelio Vascular/citología , Miembro Posterior , Isquemia/terapia , Neovascularización Fisiológica , Sarcoma/terapia , Enfermedades de la Piel/terapia , Cicatrización de Heridas , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad
11.
Wounds ; 31(4): E29-E32, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31008717

RESUMEN

INTRODUCTION: Microvascular tissue serves as the foundation for tissue granulation and remodeling during the wound healing process. Optimal repair of microvascular structure and function is essential for future healing capacity and to minimize tissue breakdown in a newly epithelialized wound. OBJECTIVE: This case series of 3 patients with nonhealing diabetic foot ulcers (DFUs) refractory to standard wound care demonstrates the ability of processed microvascular tissue (PMVT) to enable wound closure, increase local perfusion and vascular maturity, and improve overall tissue quality. MATERIALS AND METHODS: Three patients with nonhealing DFUs ranging from 1.1 cm2 to 11.2 cm2 recalcitrant to standard of care were treated weekly with topical PMVT and standard of care. Wound closure was measured weekly using infrared imaging. Fluorescence microangiography was used to perform dynamic quantification of wound microcirculation and assess the perfusion quality. Ingress rates were measured at 5 defined rectangular regions of interest of the wound to evaluate inflammation and microvascular integrity. RESULTS: All 3 nonhealing DFUs treated with weekly topical PMVT healed within 12 weeks (average, 6.3 ± 5.5 weeks). Assessment of healed wounds at the time of closure indicated PMVT treatment significantly improved perfusion within the newly healed wounded area and throughout the immediate surrounding tissues. No wound recurrence or tissue deterioration has been observed in more than 9 months of follow-up. CONCLUSIONS: In this series of patients, the PMVT graft demonstrated improved wound closure, increased local perfusion and vascular maturity, and improved tissue quality. This graft is a promising advanced tissue therapy for nonhealing DFUs and other complex wounds. It is now the subject of a randomized controlled trial.


Asunto(s)
Pie Diabético/patología , Trasplante de Piel , Trasplantes/irrigación sanguínea , Cicatrización de Heridas/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Pie Diabético/terapia , Femenino , Humanos , Masculino , Resultado del Tratamiento
12.
Int Wound J ; 16(3): 841-846, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30868746

RESUMEN

A new cell-tissue technology uses a patient's skin to create an in vivo expanding and self-organising full-thickness skin autograft derived from potent cutaneous appendages. This autologous homologous skin construct (AHSC) is manufactured from a small full-thickness skin harvest obtained from an uninjured area of the patient. All the harvested tissue is incorporated into the AHSC including the endogenous regenerative cellular populations responsible for skin maintenance and repair, which are activated during the manufacturing process. Without any exogenous supplementation or culturing, the AHSC is swiftly returned to the patient's wound bed, where it expands and closes the defect from the inside out with full-thickness fully functional skin. AHSC was applied to a greater than two-year old large (200 cm2 ) chronic wound refractory to multiple failed split-thickness skin grafts. Complete epithelial coverage was achieved in 8 weeks, and complete wound coverage with full-thickness functional skin occurred in 12 weeks. At 6-month follow-up, the wound remained covered with full-thickness skin, grossly equivalent to surrounding native skin qualitatively and quantitatively equivalent across multiple functions and characteristics, including sensation, hair follicle morphology, bio-impedance and composition, pigment regeneration, and gland production.


Asunto(s)
Enfermedad Crónica/terapia , Invenciones , Trasplante de Piel/métodos , Trasplante Autólogo/métodos , Cicatrización de Heridas/fisiología , Heridas y Lesiones/terapia , Adulto , Humanos , Masculino , Resultado del Tratamiento
13.
Wound Repair Regen ; 27(3): 201-224, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30767334

RESUMEN

We investigate how wound closure is determined in recent randomized controlled wound trials and real-world studies, identify solutions to the current limitations of wound assessment, and propose a standard methodology to define and assess wound healing in research. We searched PubMed for randomized clinical trials using the terms "complete wound closure" and "wound healing rate" and for real-world studies using the terms "real-world wound healing," "real-world wound data," and "wound registries" dating from March 2010 through March 2018. We selected studies that had "complete wound closure" or "healed wound" as an endpoint. Sixty-five trial articles and 10 real-world articles met our criteria, from which we extracted the wound type studied, definition of healed wound used, wound assessment method, the number of weeks assessed, the number of wounds, and the percent of healed wounds in the study group(s) and control group. There were 7,194 trial wounds included. The most common definition of healing used by 26 studies (40.6%) was complete/full/100% (re)epithelialization or closure without discharge, drainage/scab, and/or dressing. Fifty-two studies (81.2%) used blinded wound assessment, and at least 10 studies (15.6%) used blinded adjudication. The real-world studies analyzed more than 901,396 wounds. Only three studies (33.3%) defined a healed/closed wound, two of which used "complete epithelialization." Eight studies (88.9%) did not define the wound assessment method; none indicated a blinded assessment. We support the Food and Drug Administration definition: 100% reepithelialization of the wound surface with no discernable exudate and without drainage or dressing, confirmed at two visits 2 weeks apart, and we recommend blinded adjudication for wound assessment. The widespread adoption of a standard wound healing definition and assessment method in wound care research would allow for stronger comparisons of treatment effects across studies to improve the evidence base and strengthen the treatment decision-making process in clinical practice.


Asunto(s)
Investigación Biomédica , Ensayos Clínicos Controlados Aleatorios como Asunto , Traumatismos de los Tejidos Blandos/cirugía , Cicatrización de Heridas/fisiología , Vendajes , Humanos , Traumatismos de los Tejidos Blandos/patología , Dehiscencia de la Herida Operatoria , Técnicas de Sutura
14.
Nanoscale ; 10(41): 19277-19285, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30325375

RESUMEN

The phenomenon of protein aggregation is a prominent challenge that impacts biopharmaceutical development at every stage. It may have a number of deleterious effects on protein drugs, including the loss of efficacy, induction of immunogenicity, altered pharmacokinetics and reduced shelf life. At present, multiple methods are available for counting and sizing particles over a broad range of sizes. However, there remains a conundrum in the measurement of particles in the submicrometer range, from 100 nm to 2 µm. In this study, the capability of our new laboratory built FCM system to detect model polystyrene (PS) and silica (SiO2) submicrometer microspheres was evaluated and benchmarked against flow field-flow fractionation (FFF). The FCM system showed its advantages on sensitivity, selectivity, reproducibility and speed. The laboratory-built FCM system can readily analyze model PS and SiO2 microspheres down to 200 nm, covering much of the difficult range from 100 nm to 2 µm. Our data also showed that this machine was able to monitor the distribution of antibody aggregates ranged between 200 nm and 10 µm, suggesting its usability for characterizing protein aggregation in future.


Asunto(s)
Anticuerpos/química , Citometría de Flujo/métodos , Anticuerpos/metabolismo , Citometría de Flujo/instrumentación , Fraccionamiento de Campo-Flujo , Tamaño de la Partícula , Poliestirenos/química , Agregado de Proteínas/fisiología , Relación Señal-Ruido , Dióxido de Silicio/química
15.
Int Wound J ; 15(5): 731-739, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29682897

RESUMEN

Aseptically processed human reticular acellular dermal matrix (HR-ADM) has been previously shown to improve wound closure in 40 diabetic patients with non-healing foot ulcers. The study was extended to 40 additional patients (80 in total) to validate and extend the original findings. The entire cohort of 80 patients underwent appropriate offloading and standard of care (SOC) during a 2-week screening period and, after meeting eligibility criteria, were randomised to receive weekly applications of HR-ADM plus SOC or SOC alone for up to 12 weeks. The primary outcome was the proportion of wounds closed at 6 weeks. Sixty-eight percent (27/40) in the HR-ADM group were completely healed at 6 weeks compared with 15% (6/40) in the SOC group. The proportions of wounds healed at 12 weeks were 80% (34/40) and 30% (12/40), respectively. The mean time to heal within 12 weeks was 38 days for the HR-ADM group and 72 days for the SOC group. There was no incidence of increased adverse or serious adverse events between groups or any graft-related adverse events. The mean and median HR-ADM product costs at 12 weeks were $1200 and $680, respectively. HR-ADM is clinically superior to SOC, is cost effective relative to other comparable treatment modalities, and is an efficacious treatment for chronic non-healing diabetic foot ulcers.


Asunto(s)
Dermis Acelular , Pie Diabético/terapia , Trasplante de Piel/métodos , Cicatrización de Heridas/fisiología , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
16.
Acta Ophthalmol ; 96(1): e1-e9, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27874278

RESUMEN

The role of vascular endothelial growth factor (VEGF), including in retinal vascular diseases, has been well studied, and pharmacological blockade of VEGF is the gold standard of treatment for neovascular age-related macular degeneration, retinal vein occlusion and diabetic macular oedema. Placental growth factor (PGF, previously known as PlGF), a homologue of VEGF, is a multifunctional peptide associated with angiogenesis-dependent pathologies in the eye and non-ocular conditions. Animal studies using genetic modification and pharmacological treatment have demonstrated a mechanistic role for PGF in pathological angiogenesis. Inhibition decreases neovascularization and microvascular abnormalities across different models, including oxygen-induced retinopathy, laser-induced choroidal neovascularization and in diabetic mice exhibiting retinopathies. High levels of PGF have been found in the vitreous of patients with diabetic retinopathy. Despite these strong animal data, the exact role of PGF in pathological angiogenesis in retinal vascular diseases remains to be defined, and the benefits of PGF-specific inhibition in humans with retinal neovascular diseases and macular oedema remain controversial. Comparative effectiveness research studies in patients with diabetic retinal disease have shown that treatment that inhibits both VEGF and PGF may provide superior outcomes in certain patients compared with treatment that inhibits only VEGF. This review summarizes current knowledge of PGF, including its relationship to VEGF and its role in pathological angiogenesis in retinal diseases, and identifies some key unanswered questions about PGF that can serve as a pathway for future basic, translational and clinical research.


Asunto(s)
Neovascularización Coroidal/metabolismo , Retinopatía Diabética/metabolismo , Factor de Crecimiento Placentario/metabolismo , Retina/metabolismo , Neovascularización Retiniana/metabolismo , Animales , Humanos
17.
Wound Repair Regen ; 25(3): 454-465, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28370922

RESUMEN

Wounds that exhibit delayed healing add extraordinary clinical, economic, and personal burdens to patients, as well as to increasing financial costs to health systems. New interventions designed to ease such burdens for patients with cancer, renal, or ophthalmologic conditions are often cleared for approval by the U.S. Food and Drug Administration (FDA) using multiple endpoints but the requirement of complete healing as a primary endpoint for wound products impedes FDA clearance of interventions that can provide other clinical or patient-centered benefits for persons with wounds. A multidisciplinary group of wound experts undertook an initiative, in collaboration with the FDA, to identify and content validate supporting FDA criteria for qualifying wound endpoints relevant to clinical practice (CP) and patient-centered outcomes (PCO) as primary outcomes in clinical trials. As part of the initiative, a research study was conducted involving 628 multidisciplinary expert wound clinicians and researchers from 4 different groups: the interdisciplinary core advisory team; attendees of the Spring 2015 Symposium on Advanced Wound Care (SAWC); clinicians employed by a national network of specialty clinics focused on comprehensive wound care; and Association for the Advancement of Wound Care (AAWC) and Wound Healing Society (WHS) members who had not previously completed the survey. The online survey assessed 28 literature-based wound care endpoints for their relevance and importance to clinical practice and clinical research. Fifteen of the endpoints were evaluated for their relevance to improving quality of life. Twenty-two endpoints had content validity indexes (CVI) ≥ 0.75, and 15 were selected as meriting potential inclusion as additional endpoints for FDA approval of future wound care interventions. This study represents an important first step in identifying and validating new measurable wound care endpoints for clinical research and practice and for regulatory evaluation.


Asunto(s)
Atención a la Salud/organización & administración , Determinación de Punto Final , United States Food and Drug Administration/legislación & jurisprudencia , Técnicas de Cierre de Heridas , Cicatrización de Heridas , Infección de Heridas/prevención & control , Heridas y Lesiones/terapia , Aprobación de Recursos , Aprobación de Drogas , Humanos , Medición de Resultados Informados por el Paciente , Prueba de Estudio Conceptual , Garantía de la Calidad de Atención de Salud/organización & administración , Ensayos Clínicos Controlados Aleatorios como Asunto , Encuestas y Cuestionarios , Estados Unidos
18.
Wounds ; 29(2): 39-45, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28272011

RESUMEN

BACKGROUND: Acellular matrices have been successfully used to heal indolent diabetic foot ulcers (DFUs). These tissues include allogenic dermis as well as xenograft dermis, pericardium, and small intestine submucosa. While all of these tissues show promise for healing DFUs, dermal-derived matrices have shown considerable potential. MATERIALS AND METHODS: The authors retrospectively reviewed healing in patients with DFUs that failed the standard of care (SOC) treatment from a previous prospective randomized, controlled trial (RCT). That trial compared the efficacy of human reticular acellular dermal matrices (HR-ADMs) with the SOC. Of the 16 out of 20 patients who did not heal in the SOC group, 12 were eligible for crossover treatment with the HR-ADM. The authors studied the rate of complete healing in that specific cohort after 12 weeks of crossover treatment. RESULTS: Of the 12 patients who were eligible for the HR-ADM, 10 (83%) achieved complete wound healing, with a mean healing time of 21 days to closure. The corresponding wound area reduction was from 1.7 cm2 to 0.6 cm2. The mean product cost to closure was $800/patient. CONCLUSION: This study further demonstrates the effectiveness of the HR-ADM in facilitating the closure of nonhealing DFUs refractory to SOC.


Asunto(s)
Dermis Acelular , Colágeno/metabolismo , Pie Diabético/terapia , Trasplante de Piel , Cicatrización de Heridas/fisiología , Análisis Costo-Beneficio , Estudios Cruzados , Pie Diabético/patología , Pie Diabético/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante de Piel/métodos , Resultado del Tratamiento
19.
Int Wound J ; 14(3): 460-469, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27374428

RESUMEN

Although macrovascular screening of patients with chronic wounds, particularly in the lower extremities, is accepted as part of clinical practice guidelines, microvascular investigation is less commonly used for a variety of reasons. This can be an issue because most patients with macrovascular disease also develop concomitant microvascular dysfunction. Part of the reason for less comprehensive microvascular screening has been the lack of suitable imaging techniques that can quantify microvascular dysfunction in connection with non-healing chronic wounds. This is changing with the introduction of fluorescence microangiography. The objective of this review is to examine macro- and microvascular disease, the strengths and limitations of the approaches used and to highlight the importance of microvascular angiography in the context of wound healing.


Asunto(s)
Microvasos/diagnóstico por imagen , Microvasos/fisiología , Cicatrización de Heridas/fisiología , Heridas y Lesiones/diagnóstico por imagen , Heridas y Lesiones/fisiopatología , Enfermedad Crónica , Humanos , Microscopía Fluorescente
20.
Int Wound J ; 14(2): 307-315, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27073000

RESUMEN

Acellular dermal matrices can successfully heal wounds. This study's goal was to compare clinical outcomes of a novel, open-structure human reticular acellular dermis matrix (HR-ADM) to facilitate wound closure in non-healing diabetic foot ulcers (DFUs) versus DFUs treated with standard of care (SOC). Following a 2-week screening period in which DFUs were treated with offloading and moist wound care, patients were randomised to either SOC alone or HR-ADM plus SOC applied weekly for up to 12 weeks. At 6 weeks, the primary outcome time, 65% of the HR-ADM-treated DFUs healed (13/20) compared with 5% (1/20) of DFUs that received SOC alone. At 12 weeks, the proportions of DFUs healed were 80% and 20%, respectively. Mean time to heal within 12 weeks was 40 days for the HR-ADM group compared with 77 days for the SOC group. There was no incidence of increased adverse or serious adverse events between groups or any adverse events related to the graft. Mean and median graft costs to closure per healed wound in the HR-ADM group were $1475 and $963, respectively. Weekly application of HR-ADM is an effective intervention for promoting closure of non-healing DFUs.


Asunto(s)
Dermis Acelular/economía , Enfermedad Crónica/economía , Enfermedad Crónica/terapia , Pie Diabético/economía , Pie Diabético/terapia , Piel Artificial/economía , Cicatrización de Heridas/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Nivel de Atención , Resultado del Tratamiento , Adulto Joven
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