RESUMEN
Solutions containing Ag0 nanoclusters, Ag+1, and higher oxidation state silver, generated from nanocrystalline silver dressings, were anti-inflammatory against porcine skin inflammation. The dressings have clinically-demonstrated broad-spectrum antimicrobial activity, suggesting application of nanosilver solutions in treating pulmonary infection. Nanosilver solutions were tested for antimicrobial efficacy; against HSV-1 and SARS-CoV-2; and nebulized in rats with acute pneumonia. Patients with pneumonia (ventilated), fungal sinusitis, burns plus COVID-19, and two non-hospitalized patients with COVID-19 received nebulized nanosilver solution. Nanosilver solutions demonstrated pH-dependent antimicrobial efficacy; reduced infection and inflammation without evidence of lung toxicity in the rat model; and inactivated HSV-1 and SARS-CoV-2. Pneumonia patients had rapidly reduced pulmonary symptoms, recovering pre-illness respiratory function. Fungal sinusitis-related inflammation decreased immediately with infection clearance within 21 days. Non-hospitalized patients with COVID-19 experienced rapid symptom remission. Nanosilver solutions, due to anti-inflammatory, antiviral, and antimicrobial activity, may be effective for treating respiratory inflammation and infections caused by viruses and/or microbes.
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COVID-19 , Neumonía , Sinusitis , Ratas , Animales , Porcinos , COVID-19/complicaciones , SARS-CoV-2 , Plata/uso terapéutico , Inflamación/tratamiento farmacológico , Neumonía/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Sinusitis/complicaciones , Sinusitis/tratamiento farmacológicoRESUMEN
The Wound Healing Foundation (WHF) recognised a need for an unbiased consensus on the best treatment of chronic wounds. A panel of 13 experts were invited to a virtual meeting which took place on 27 March 2021. The proceedings were organised in the sub-sections diagnosis, debridement, infection control, dressings, grafting, pain management, oxygen treatment, outcomes and future needs. Eighty percent or better concurrence among the panellists was considered a consensus. A large number of critical questions were discussed and agreed upon. Important takeaways included that wound care needs to be simplified to a point that it can be delivered by the patient or the patient's family. Another one was that telemonitoring, which has proved very useful during the COVID-19 pandemic, can help reduce the frequency of interventions by a visiting nurse or a wound care center. Defining patient expectations is critical to designing a successful treatment. Patient outcomes might include wound specific outcomes such as time to heal, wound size reduction, as well as improvement in quality of life. For those patients with expectations of healing, an aggressive approach to achieve that goal is recommended. When healing is not an expectation, such as in patients receiving palliative wound care, outcomes might include pain reduction, exudate management, odour management and/or other quality of life benefits to wound care.
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COVID-19 , Cicatrización de Heridas , COVID-19/terapia , Consenso , Humanos , Pandemias , Calidad de VidaRESUMEN
During herpes simplex virus (HSV) latency, most viral genes are silenced, with the exception of one region of the genome encoding the latency-associated transcript (LAT). This long noncoding RNA was originally described as having a role in enhancing HSV-1 reactivation. However, subsequent evidence showing that the LAT blocked apoptosis and promoted efficient establishment of latency suggested that its effects on reactivation were secondary to establishment. Here, we utilized an adeno-associated virus (AAV) vector to deliver a LAT-targeting hammerhead ribozyme to HSV-1-infected neurons of rabbits after the establishment of HSV-1 latency. The rabbits were then induced to reactivate latent HSV-1. Using this model, we show that decreasing LAT levels in neurons following the establishment of latency reduced the ability of the virus to reactivate. This demonstrates that the HSV-1 LAT RNA has a role in reactivation that is independent of its function in establishment of latency. In addition, these results suggest the potential of AAV vectors expressing LAT-targeting ribozymes as a potential therapy for recurrent HSV disease such as herpes stromal keratitis, a leading cause of infectious blindness.IMPORTANCE Herpes simplex virus (HSV) establishes a lifelong infection and remains dormant (latent) in our nerve cells. Occasionally HSV reactivates to cause disease, with HSV-1 typically causing cold sores whereas HSV-2 is the most common cause of genital herpes. The details of how HSV reactivates are largely unknown. Most of HSV's genes are silent during latency, with the exception of RNAs made from the latency-associated transcript (LAT) region. While viruses that make less LAT do not reactivate efficiently, these viruses also do not establish latency as efficiently. Here we deliver a ribozyme that can degrade the LAT to the nerve cells of latently infected rabbits using a gene therapy vector. We show that this treatment blocks reactivation in the majority of the rabbits. This work shows that the LAT RNA is important for reactivation and suggests the potential of this treatment as a therapy for treating HSV infections.
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Regulación Viral de la Expresión Génica , Herpesvirus Humano 1/fisiología , ARN Largo no Codificante/metabolismo , ARN Viral/metabolismo , Activación Viral , Latencia del Virus , Animales , Células Cultivadas , Dependovirus/genética , Vectores Genéticos , Herpesvirus Humano 1/genética , Neuronas/virología , ARN Catalítico/genética , ARN Catalítico/metabolismo , ARN Largo no Codificante/genética , ARN Viral/genética , Conejos , Transcripción GenéticaRESUMEN
Despite the understanding that wounds are a common problem affecting the individual, the health service and society as a whole, there continues to be a lack of a systematic, structured, evidence-based approach to wound management. The TIME principle was first published in 2003, 1 and has since been integrated by many into clinical practice and research. However, this tool has been criticised for its tendency to focus mainly on the wound rather than on the wider issues that the patient is presenting with. At an expert meeting held in London in 2018, this conundrum was addressed and the TIME clinical decision support tool (CDST) was elaborated upon. This article introduces the TIME CDST, explains why it is required and describes how its use is likely to benefit patients, clinicians and health-service organisations. It also explores the framework in detail, and shows why this simple and accessible framework is robust enough to facilitate consistency in the delivery of wound care and better patient outcomes. Finally, it outlines the next steps for the rollout, use and evaluation of the impact of the TIME CDST.
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Sistemas de Apoyo a Decisiones Clínicas , Úlcera Cutánea/terapia , Consenso , Dermatología , HumanosRESUMEN
Biofilms are prevalent in non-healing chronic wounds and implicated in delayed healing. Tolerance to antimicrobial treatments and the host's immune system leave clinicians with limited interventions against biofilm populations. It is therefore essential that effective treatments be rigorously tested and demonstrate an impact on biofilm across multiple experimental models to guide clinical investigations and protocols. Cadexomer iodine has previously been shown to be effective against biofilm in various in vitro models, against methicillin-resistant Staphylococcus aureus biofilm in mouse wounds, and clinically in diabetic foot ulcers complicated by biofilm. Similarities between porcine and human skin make the pig a favoured model for cutaneous wound studies. Two antiseptic dressings and a gauze control were assessed against mature biofilm grown on ex vivo pig skin and in a pig wound model. Significant reductions in biofilm were observed following treatment with cadexomer iodine across both biofilm models. In contrast, silver carboxymethylcellulose dressings had minimal impact on biofilm in the models, with similar results to the control in the ex vivo model. Microscopy and histopathology indicate that the depth of organisms in wound tissue may impact treatment effectiveness. Further work on the promising biofilm efficacy of cadexomer iodine is needed to determine optimal treatment durations against biofilm.
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Antiinfecciosos Locales/uso terapéutico , Biopelículas/efectos de los fármacos , Yodóforos/uso terapéutico , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Infección de Heridas/tratamiento farmacológico , Animales , Enfermedad Crónica/tratamiento farmacológico , Humanos , Modelos Animales , PorcinosRESUMEN
OBJECTIVE: Removal of slough and other devitalised tissue is an important step in biofilm-based wound care (BBWC) and wound bed preparation. Debridement is key to management of both slough and biofilm, and a number of methods are available to achieve this, including surgical/sharp and mechanical debridement. Developments have led to products indicated for debridement of wounds, including a sterile pad consisting of monofilament fibres. Our aim is to examine the effectiveness of a monofilament wound debridement pad (WDP), Debrisoft. METHOD: We assessed the WDP, in laboratory tests, for the removal of mature biofilm from porcine dermal tissue in an ex vivo model, and the clinical management of sloughy wounds that would benefit from debridement. We used the UPPER score to determine the superficial infection status. RESULTS: The WDP was effective in removing biofilm from porcine dermal tissue. A case series of 10 patients with chronic wounds suggested that the WDP was beneficial in the removal of slough. All chronic wounds had slough and were cleaned weekly, for four weeks, using the MDP to achieve improved healing and a clean wound bed. The average wound size decreased from 8.09cm2 at baseline to 2.3cm2 at week four, with three wounds healed completely. Exudate was reduced, and the UPPER score improved in every patient. CONCLUSION: These results indicate that the WDP effectively debrides biofilm and slough, and contributes to care that follows the principles of wound bed preparation and BBWC.
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Vendajes , Desbridamiento/instrumentación , Infecciones por Pseudomonas/cirugía , Pseudomonas aeruginosa , Infección de la Herida Quirúrgica/cirugía , Anciano , Anciano de 80 o más Años , Animales , Biopelículas , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Necrosis/cirugía , Piel/patología , PorcinosRESUMEN
UNLABELLED: Following infection of epithelial tissues, herpes simplex virus 1 (HSV-1) virions travel via axonal transport to sensory ganglia and establish a lifelong latent infection within neurons. Recent studies have revealed that, following intraganglionic or intrathecal injection, recombinant adeno-associated virus (rAAV) vectors can also infect sensory neurons and are capable of stable, long-term transgene expression. We sought to determine if application of rAAV to peripheral nerve termini at the epithelial surface would allow rAAV to traffic to sensory ganglia in a manner similar to that seen with HSV. We hypothesized that footpad or ocular inoculation with rAAV8 would result in transduction of dorsal root ganglia (DRG) or trigeminal ganglia (TG), respectively. To test this, we inoculated the footpads of mice with various amounts of rAAV as well as rAAV capsid mutants. We demonstrated that this method of inoculation can achieve a transduction rate of >90% of the sensory neurons in the DRG that innervate the footpad. Similarly, we showed that corneal inoculation with rAAV vectors in the rabbit efficiently transduced >70% of the TG neurons in the optic tract. Finally, we demonstrated that coinfection of mouse footpads or rabbit eyes with rAAV vectors and HSV-1 resulted in colocalization in nearly all of the HSV-1-positive neurons. These results suggest that rAAV is a useful tool for the study of HSV-1 infection and may provide a means to deliver therapeutic cargos for the treatment of HSV infections or of dysfunctions of sensory ganglia. IMPORTANCE: Adeno-associated virus (AAV) has been shown to transduce dorsal root ganglion sensory neurons following direct intraganglionic sciatic nerve injection and intraperitoneal and intravenous injection as well as intrathecal injection. We sought to determine if rAAV vectors would be delivered to the same sensory neurons that herpes simplex virus (HSV-1) infects when applied peripherally at an epithelial surface that had been treated to expose the underlying sensory nerve termini. For this study, we chose two well-established HSV-1 infection models: mouse footpad infection and rabbit ocular infection. The results presented here provide the first description of AAV vectors transducing neurons following delivery at the skin/epithelium/eye. The ability of AAV to cotransduce HSV-1-infected neurons in both the mouse and the rabbit provides an opportunity to experimentally explore and disrupt host and viral proteins that are integral to the establishment of HSV-1 latency, to the maintenance of latency, and to reactivation from latency in vivo.
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Dependovirus/crecimiento & desarrollo , Dependovirus/genética , Vectores Genéticos , Herpesvirus Humano 1/crecimiento & desarrollo , Células Receptoras Sensoriales/virología , Transducción Genética , Animales , Coinfección/virología , Ojo/virología , Pie/virología , Ganglios Espinales/virología , Herpes Simple/virología , Ratones , Infecciones por Parvoviridae/virología , Conejos , Ganglio del Trigémino/virologíaRESUMEN
Proteinases are enzymes that can digest other proteins. In chronic wounds, a sub-class of these enzymes with the ability to degrade the extracellular matrix (matrix metalloproteinases, MMPs) have been found to both inhibit healing and to be able to aid in enzymatically debriding a wound. Enzymatic debridement using the enzymes present in a wound is generally called autolytic debridement. Clinicians seeking to employ autolytic debridement typically use occlusive materials such as medical honey, alginate dressings and other occlusive dressings. A relatively new class of gel dressings comprised of surfactants are now available for clinical use. A variety of surfactants are used in the study of MMP biochemistry. Surfactants can deactivate MMPs or can enhance their activity, depending on the surfactant. In order to begin to understand how the MMPs found in chronic wounds would respond to these new dressings, we tested a serial dilution series of two of the currently available surfactant-based dressings to determine their effects on four separate MMPs. The dose-response versus MMP activity of bacterial collagenase, host-derived MMP-8 and MMPs-2 and -9 was assessed using a simple mix-and-read fluorescent peptide activity assay. The enzyme's native activity in the absence of the gel was used to compare against the surfactant-treated samples. We found that the surfactant affected the proteinase activity differently for each enzyme. The activity of the bacterial collagenase was increased at low concentrations but slightly inhibited as the concentrations increased. The host MMP-8 collagenase responded similarly in that it was inhibited at higher concentrations. Interestingly, both MMP gelatinases presented with substantially increased activities, with MMP-2 increased to 200% of native activity, while MMP-9 presented with an increase of 300% activity over the same concentration range. MMPs appear to respond to a surfactant-based gel dressing differentially, with the MMP most commonly elevated in chronic wounds having the highest boost to activity. In wounds with elevated MMPs, our data suggest that the use of these surfactant-based dressings would be expected to enhance the activity of MMPs 2 and 9 gelatinases while simultaneously inhibiting MMP-8 collagenase. Hypothetically, this imbalanced effect would support a protection of the native dermal collagen and removal of denatured materials. However, the demonstration of these anticipated consequences is still being investigated.
Asunto(s)
Colagenasas/metabolismo , Desbridamiento/métodos , Metaloproteinasas de la Matriz/metabolismo , Apósitos Oclusivos , Tensoactivos/farmacología , Cicatrización de Heridas/fisiología , HumanosRESUMEN
Bacterial biofilms have been found in many, if not all, chronic wounds. Their excessive extracellular matrix secretion and the metabolic changes that they undergo render them highly tolerant of many antibiotic and antimicrobial treatments. Physical removal and/or disruption are a common approach to treating wounds suspected of having bacterial biofilms. While many of these techniques use mechanical energy as the primary means of removal, we have begun to investigate if surfactants could facilitate the removal of bacterial biofilms, or if they might sensitise the biofilms to antimicrobial interventions. We tested a new surfactant-based wound gel on an ex vivo porcine skin explant model infected with a functionally tolerant 3-day biofilm. The wounds were dressed with a surfactant-based gel directly on the wound or with moistened gauze. The wounds were then wiped daily with moistened gauze, and the gel or gauze was re-applied. Each day, an explant from each group was harvested and tested for total viable bacteria counts and viable biofilm-protected bacteria counts. The results show that daily wiping with moistened gauze led to an initial decrease of bacteria, but by day 3, the biofilm had been fully re-established to the same level prior to the beginning of treatment. For the surfactant-based treatment, there was no detectable functional biofilm after the first treatment. The gauze control, which was also subjected to daily wiping, still contained functional biofilms, indicating that this result was not due to wiping alone. The total bacteria in the surfactant-treated explants steadily decreased through day 3, when there were no detectable bacteria, while the wiping-only control bacteria counts remained steady. The use of a moist gauze to wipe the visually apparent slime off of a wound appears to be insufficient to reduce biofilm over a 3-day period. Daily application of the surfactant gel dressing and wiping reduced the biofilm to undetectable levels within 3 days in a skin explant model. A 3-day regimen of dressing the wound model with a surfactant gel followed by gentle removal of the gel by wiping with a moistened gauze appears to be a simple and adequate approach to removing a bacterial biofilm infection in an ex vivo model. Additional clinical evidence is needed to determine if this promising approach can perform the same in clinically infected chronic wounds.
Asunto(s)
Antiinfecciosos/uso terapéutico , Vendajes , Biopelículas/efectos de los fármacos , Infecciones por Pseudomonas/tratamiento farmacológico , Tensoactivos/uso terapéutico , Trasplantes/microbiología , Infección de Heridas/tratamiento farmacológico , Animales , Femenino , Humanos , Masculino , Pseudomonas aeruginosa/efectos de los fármacos , Porcinos , Cicatrización de HeridasRESUMEN
Hepatic progenitor/oval cell (OC) activation occurs when hepatocyte proliferation is inhibited and is tightly associated with the fibrogenic response during severe liver damage. Connective tissue growth factor (CTGF) is important for OC activation and contributes to the pathogenesis of liver fibrosis. By using the Yeast Two-Hybrid approach, we identified a disintegrin and metalloproteinase with thrombospondin repeat 7 (ADAMTS7) as a CTGF binding protein. In vitro characterization demonstrated CTGF binding and processing by ADAMTS7. Moreover, Adamts7 mRNA was induced during OC activation, after the implantation of 2-acetylaminofluorene with partial hepatectomy in rats or on feeding a 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet in mice. X-Gal staining showed Adamts7 expression in hepatocyte nuclear factor 4α(+) hepatocytes and desmin(+) myofibroblasts surrounding reactive ducts in DDC-treated Adamts7(-/-) mice carrying a knocked-in LacZ gene. Adamts7 deficiency was associated with higher transcriptional levels of Ctgf and OC markers and enhanced OC proliferation compared to Adamts7(+/+) controls during DDC-induced liver injury. We also observed increased α-smooth muscle actin and procollagen type I mRNAs, large fibrotic areas in α-smooth muscle actin and Sirius red staining, and increased production of hepatic collagen by hydroxyproline measurement. These results suggest that ADAMTS7 is a new protease for CTGF protein and a novel regulator in the OC compartment, where its absence causes CTGF accumulation, leading to increased OC activation and biliary fibrosis.
Asunto(s)
Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Desintegrinas/metabolismo , Cirrosis Hepática/metabolismo , Hígado/metabolismo , Nicho de Células Madre/fisiología , Trombospondinas/metabolismo , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Proteína ADAMTS7 , Animales , Factor de Crecimiento del Tejido Conjuntivo/genética , Desintegrinas/genética , Hígado/patología , Cirrosis Hepática/patología , Regeneración Hepática/fisiología , Ratones , Ratones Noqueados , Trombospondinas/genéticaRESUMEN
UNLABELLED: Connective tissue growth factor (CTGF) is a matricellular protein that mediates cell-matrix interaction through various subtypes of integrin receptors. This study investigated the role of CTGF and integrin αvß6 in hepatic progenitor/oval cell activation, which often occurs in the form of ductular reactions (DRs) when hepatocyte proliferation is inhibited during severe liver injury. CTGF and integrin αvß6 proteins were highly expressed in DRs of human cirrhotic livers and cholangiocarcinoma. Confocal microscopy analysis of livers from Ctgf promoter-driven green fluorescent protein reporter mice suggested that oval cells and cholangiocytes were the main sources of CTGF and integrin αvß6 during liver injury induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Deletion of exon 4 of the Ctgf gene using tamoxifen-inducible Cre-loxP system down-regulated integrin αvß6 in DDC-damaged livers of knockout mice. Ctgf deficiency or inhibition of integrin αvß6, by administrating the neutralizing antibody, 6.3G9 (10 mg/kg body weight), caused low levels of epithelial cell adhesion molecule and cytokeratin 19 gene messenger RNAs. Also, there were smaller oval cell areas, fewer proliferating ductular epithelial cells, and lower cholestasis serum markers within 2 weeks after DDC treatment. Associated fibrosis was attenuated, as indicated by reduced expression of fibrosis-related genes, smaller areas of alpha-smooth muscle actin staining, and low collagen production based on hydroxyproline content and Sirius Red staining. Finally, integrin αvß6 could bind to CTGF mediating oval cell adhesion to CTGF and fibronection substrata and promoting transforming growth factor (TGF)-ß1 activation in vitro. CONCLUSIONS: CTGF and integrin αvß6 regulate oval cell activation and fibrosis, probably through interacting with their common matrix and signal partners, fibronectin and TGF-ß1. CTGF and integrin αvß6 are potential therapeutic targets to control DRs and fibrosis in related liver disease.
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Antígenos de Neoplasias/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Integrinas/metabolismo , Cirrosis Hepática/metabolismo , Células Madre Adultas/metabolismo , Animales , Neoplasias de los Conductos Biliares/metabolismo , Conductos Biliares Intrahepáticos , Adhesión Celular , Colangiocarcinoma/metabolismo , Femenino , Fibronectinas/metabolismo , Humanos , Masculino , Ratones , Ratones Noqueados , Piridinas , Conejos , Ratas , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
An ex vivo porcine skin explant biofilm model that preserves key properties of biofilm attached to skin at different levels of maturity (0-3 days) was used to assess the efficacy of commercially available antimicrobial dressings and topical treatments. Assays were also performed on the subpopulation of antibiotic tolerant biofilm generated by 24 hours of pre-treatment with gentamicin (120× minimal inhibitory concentration) prior to agent exposure. Five types of antimicrobial agents (iodine, silver, polyhexamethylene biguanide, honey and ethanol) and four types of moisture dressings (cotton gauze, sodium carboxymethylcellulose fibre, calcium alginate fibre and cadexomer beads) were assessed. Time-release silver gel and cadexomer iodine dressings were the most effective in reducing mature biofilm [between 5 and 7 logarithmic (log) of 7-log total], whereas all other dressing formulations reduced biofilm between 0·3 and 2 log in 24 or 72 hours with a single exposure. Similar results were found after 24-hour exposure to silver release dressings using an in vivo pig burn wound model, demonstrating correlation between the ex vivo and in vivo models. Results of this study indicate that commonly used microbicidal wound dressings vary widely in their ability to kill mature biofilm and the efficacy is influenced by time of exposure, number of applications, moisture level and agent formulation (sustained release).
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Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Vendajes , Biopelículas/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Piel/microbiología , Infección de Heridas/tratamiento farmacológico , Animales , Células Cultivadas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Animales , PorcinosRESUMEN
A bipedicle ischaemic rat skin flap model was used to study the effects of daily topical applications of platelet-derived growth factor (PDGF) on the healing of ischaemic wounds. Levels of tumour necrosis factor-alpha (TNFA), interleukin 1-beta (IL1B) and both the latent and active forms of matrix metalloproteinase 2 (MMP2) and 9 (MMP9) were measured. Full-thickness wounds were made on a total of 72 adult male Sprague-Dawley rats. Each group of 18 rats with normal and ischaemic wounds received either vehicle or 0·01% recombinant PDGF-BB. Additional applications were made on the wounds on a daily basis. Wound areas were measured at 0, 1, 3, 5, 7 9 and 13 days after wounding. Ischaemia caused a delay in wound healing as well as an increase in TNFA, IL1B and both the pro and active forms of MMP2 and MMP9. PDGF accelerated the rate of wound healing in both normal and ischaemic wounds and negated the effect of ischaemia. PDGF reduced the TNFA concentration in both normal and ischaemic wounds, and the rate of wound healing closely resembled the pattern of TNFA protein expression. PDGF also reduced both the magnitude and duration of the increases in IL1B and both the pro and active forms of MMP2 and MMP9 induced by ischaemia.
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Inductores de la Angiogénesis/uso terapéutico , Proteínas Proto-Oncogénicas c-sis/uso terapéutico , Cicatrización de Heridas/fisiología , Heridas Penetrantes/tratamiento farmacológico , Administración Tópica , Animales , Becaplermina , Modelos Animales de Enfermedad , Interleucina-1beta/metabolismo , Isquemia/complicaciones , Isquemia/metabolismo , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismo , Heridas Penetrantes/etiología , Heridas Penetrantes/metabolismoRESUMEN
Blood vessels are formed during development and tissue repair through a plethora of modifiers that coordinate efficient vessel assembly in various cellular settings. Here we used the yeast 2-hybrid approach and demonstrated a broad affinity of connective tissue growth factor (CCN2/CTGF) to C-terminal cystine knot motifs present in key angiogenic regulators Slit3, von Willebrand factor, platelet-derived growth factor-B, and VEGF-A. Biochemical characterization and histological analysis showed close association of CCN2/CTGF with these regulators in murine angiogenesis models: normal retinal development, oxygen-induced retinopathy (OIR), and Lewis lung carcinomas. CCN2/CTGF and Slit3 proteins worked in concert to promote in vitro angiogenesis and downstream Cdc42 activation. A fragment corresponding to the first three modules of CCN2/CTGF retained this broad binding ability and gained a dominant-negative function. Intravitreal injection of this mutant caused a significant reduction in vascular obliteration and retinal neovascularization vs. saline injection in the OIR model. Knocking down CCN2/CTGF expression by short-hairpin RNA or ectopic expression of this mutant greatly decreased tumorigenesis and angiogenesis. These results provided mechanistic insight into the angiogenic action of CCN2/CTGF and demonstrated the therapeutic potential of dominant-negative CCN2/CTGF mutants for antiangiogenesis.
Asunto(s)
Factor de Crecimiento del Tejido Conjuntivo/fisiología , Motivos Nodales de Cisteina/efectos de los fármacos , Neovascularización Fisiológica/fisiología , Animales , Carcinoma Pulmonar de Lewis/inducido químicamente , Motivos Nodales de Cisteina/genética , Células Endoteliales de la Vena Umbilical Humana , Humanos , Proteínas de la Membrana/fisiología , Ratones , Neovascularización Fisiológica/efectos de los fármacos , Vasos Retinianos/crecimiento & desarrollo , Técnicas del Sistema de Dos HíbridosRESUMEN
Bacterial biofilms have been proposed to be a major factor contributing to the failure of chronic wounds to heal because of their increased tolerance to antimicrobial agents and the prolonged inflammation they cause. Phenotypic characteristics of bacterial biofilms vary depending on the substratum to which they attach, the nutritional environment, and the microorganisms within the biofilm community. To develop an ex vivo biofilm model that more closely mimics biofilms in chronic skin wounds, we developed an optimal procedure to grow mature biofilms on a central partial-thickness wound in 12-mm porcine skin explants. Chlorine gas produced optimal sterilization of explants while preserving histological properties of the epidermis and dermis. Pseudomonas aeruginosa and Staphylococcus aureus developed mature biofilms after 3 days that had dramatically increased tolerance to gentamicin and oxacillin (â¼100× and 8,000× minimal inhibitory concentration, respectively) and to sodium hypochlorite (0.6% active chlorine). Scanning electron microscopy and confocal microscopy verified extensive exopolymeric biofilm structures on the explants. Despite a significant delay, a ΔlasI quorum-sensing mutant of P. aeruginosa developed biofilm as antibiotic-tolerant as wild-type after 3 days. This ex vivo model simulates growth of biofilms on skin wounds and provides an accurate model to assess effects of antimicrobial agents on mature biofilms.
Asunto(s)
Biopelículas/crecimiento & desarrollo , Epidermis/patología , Infecciones por Pseudomonas/patología , Infecciones Estafilocócicas/patología , Cicatrización de Heridas , Infección de Heridas/patología , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Epidermis/microbiología , Gentamicinas/farmacología , Microscopía Electrónica de Rastreo , Oxacilina/farmacología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Reproducibilidad de los Resultados , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación , Porcinos , Cicatrización de Heridas/efectos de los fármacos , Infección de Heridas/microbiologíaRESUMEN
Negative pressure wound therapy with instillation (NPWTi) is increasingly used as an adjunct therapy for a wide variety of infected wounds. However, the effect of NPWTi on mature biofilm in wounds has not been determined. This study assessed the effects of NPWTi using saline or various antimicrobial solutions on mature Pseudomonas aeruginosa biofilm using an ex vivo porcine skin explant biofilm model. Treatment consisted of six cycles with 10-minute exposure to instillation solution followed by 4 hours of negative pressure at -125 mm Hg over a 24-hour period. NPWTi using saline reduced bacterial levels by 1-log (logarithmic) of 7-log total colony-forming units (CFUs). In contrast, instillation of 1% povidone iodine (2-log), L-solution (3-log), 0·05% chlorhexidine gluconate (3-log), 0·1% polyhexamethylene biguanide (4-log), 0·2% polydiallyldimethylammonium chloride (4-log) and 10% povidone iodine (5-log), all significantly reduced (P < 0·001) total CFUs. Scanning electron micrographs showed disrupted exopolymeric matrix of biofilms and damaged bacterial cells that correlated with CFU levels. Compared with previous studies assessing microbicidal effects of topical antimicrobial dressings on biofilms cultured on porcine skin explants, these ex vivo model data suggest that NPWTi with delivery of active antimicrobial agents enhances the reduction of CFUs by increasing destruction and removal of biofilm bacteria. These results must be confirmed in human studies.
Asunto(s)
Biopelículas/crecimiento & desarrollo , Terapia de Presión Negativa para Heridas/métodos , Pseudomonas aeruginosa/fisiología , Piel/microbiología , Irrigación Terapéutica , Animales , Antiinfecciosos Locales/administración & dosificación , Carga Bacteriana/efectos de los fármacos , Biguanidas/administración & dosificación , Biopelículas/efectos de los fármacos , Clorhexidina/administración & dosificación , Clorhexidina/análogos & derivados , Microscopía Electrónica de Rastreo , Modelos Animales , Polietilenos/administración & dosificación , Povidona Yodada/administración & dosificación , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Compuestos de Amonio Cuaternario/administración & dosificación , Piel/ultraestructura , Cloruro de Sodio/administración & dosificación , Porcinos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
PURPOSE: This study investigated the efficacy and safety of vorinostat, a deacetylase (HDAC) inhibitor, in the treatment of laser-induced corneal haze following photorefractive keratectomy (PRK) in rabbits in vivo and transforming growth factor beta 1 (TGFß1) -induced corneal fibrosis in vitro. METHODS: Corneal haze in rabbits was produced with -9.00 diopters (D) PRK. Fibrosis in cultured human and rabbit corneal fibroblasts was activated with TGFß1. Vorinostat (25 µm) was topically applied once for 5 minutes on rabbit cornea immediately after PRK for in vivo studies. Vorinostat (0 to 25 µm) was given to human/rabbit corneal fibroblasts for 5 minutes or 48 hours for in vitro studies. Slit-lamp microscopy, TUNEL assay, and trypan blue were used to determined vorinostat toxicity, whereas real-time polymerase chain reaction, immunocytochemistry, and immunoblotting were used to measure its efficacy. RESULTS: Single 5-minute vorinostat (25 µm) topical application on the cornea following PRK significantly reduced corneal haze (P<.008) and fibrotic marker proteins (α-smooth muscle actin and f-actin; P<.001) without showing redness, swelling, or inflammation in rabbit eyes in vivo screened 4 weeks after PRK. Vorinostat reduced TGFß1-induced fibrosis in human and rabbit corneas in vitro in a dose-dependent manner without altering cellular viability, phenotype, or proliferation. CONCLUSIONS: Vorinostat is non-cytotoxic and safe for the eye and has potential to prevent laser-induced corneal haze in patients undergoing PRK for high myopia.
Asunto(s)
Córnea/cirugía , Opacidad de la Córnea/prevención & control , Inhibidores de Histona Desacetilasas/uso terapéutico , Ácidos Hidroxámicos/uso terapéutico , Queratectomía Fotorrefractiva , Complicaciones Posoperatorias/prevención & control , Actinas/genética , Animales , Células Cultivadas , Córnea/efectos de los fármacos , Queratocitos de la Córnea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Fibronectinas/genética , Fibrosis/inducido químicamente , Fibrosis/prevención & control , Inhibidores de Histona Desacetilasas/efectos adversos , Humanos , Ácidos Hidroxámicos/efectos adversos , Etiquetado Corte-Fin in Situ , ARN Mensajero/metabolismo , Conejos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Crecimiento Transformador beta1/farmacología , VorinostatRESUMEN
Background: Minority and older adult patients remain underrepresented in cancer clinical trials (CCTs). The current study sought to examine sociodemographic inequities in CCT interest, eligibility, enrollment, decline motivation, and attrition across two psychosocial CCTs for gynecologic, gastrointestinal, and thoracic cancers. Methods: Patients were approached for recruitment to one of two interventions: (1) a randomized control trial (RCT) examining effects of a cognitive-behavioral intervention targeting sleep, pain, mood, cytokines, and cortisol following surgery, or (2) a yoga intervention to determine its feasibility, acceptability, and effects on mitigating distress. Prospective RCT participants were queried about interest and screened for eligibility. All eligible patients across trials were offered enrollment. Patients who declined yoga intervention enrollment provided reasons for decline. Sociodemographic predictors of enrollment decisions and attrition were explored. Results: No sociodemographic differences in RCT interest were observed, and older patients were more likely to be ineligible. Eligible Hispanic patients across trials were significantly more likely to enroll than non-Hispanic patients. Sociodemographic factors predicted differences in decline motivation. In one trial, individuals originating from more urban areas were more likely to prematurely discontinue participation. Discussion: These results corroborate evidence of no significant differences in CCT interest across minority groups, with older adults less likely to fulfill eligibility criteria. While absolute Hispanic enrollment was modest, Hispanic patients were more likely to enroll relative to non-Hispanic patients. Additional sociodemographic trends were noted in decline motivation and geographical prediction of attrition. Further investigation is necessary to better understand inequities, barriers, and best recruitment practices for representative CCTs.
RESUMEN
Here, we define dynamic reciprocity (DR) as an ongoing, bidirectional interaction among cells and their surrounding microenvironment. In this review, we posit that DR is especially meaningful during wound healing as the DR-driven biochemical, biophysical, and cellular responses to injury play pivotal roles in regulating tissue regenerative responses. Such cell-extracellular matrix interactions not only guide and regulate cellular morphology, but also cellular differentiation, migration, proliferation, and survival during tissue development, including, e.g., embryogenesis, angiogenesis, as well as during pathologic processes including cancer, diabetes, hypertension, and chronic wound healing. Herein, we examine DR within the wound microenvironment while considering specific examples across acute and chronic wound healing. This review also considers how a number of hypotheses that attempt to explain chronic wound pathophysiology may be understood within the DR framework. The implications of applying the principles of DR to optimize wound care practice and future development of innovative wound healing therapeutics are also briefly considered.