| 1. |
- Gustafson, Carl-Johan, et al.
(författare)
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Employing human keratinocytes cultured on macroporous gelatin spheres to treat full thickness-wounds : an in vivo study on athymic rats.
- 2007
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Ingår i: Burns. - : Elsevier BV. - 0305-4179 .- 1879-1409. ; 33:6, s. 726-35
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Tidskriftsartikel (refereegranskat)abstract
- Providing cutaneous wounds with sufficient epidermis to prevent infections and fluid loss is one of the most challenging tasks associated with surgical treatment of burns. Recently, application of cultured keratinocytes in this context has allowed this challenge to be met without several of the limitations connected with the use of split-thickness skin grafts. The continuous development of this novel approach has now revealed that transplantation of cultured autologous keratinocytes as single-cell suspensions exhibits several advantages over the use of cultured epidermal grafts. However, a number of methodological problems remain to be solved, primarily with regards to the complexity of culturing these cells; loss of viability and other negative effects during their preparation and transportation; the relatively long period of time required following transplantation to obtain a sufficiently protective epidermis. In the present investigation we attempted to eliminate these limitations by culturing the keratinocytes on macroporous gelatin spheres. Accordingly, the efficacies of normal human keratinocytes in single-cell suspension or growing on macroporous gelatin spheres, as well as of split-thickness skin grafts in healing wounds on athymic rats were compared. Human keratinocytes were found to adhere and proliferate efficiently both on the surface and within the pores of such spheres. Transplantation of such cells adherent to the spheres resulted in significantly more rapid formation of a stratified epidermis than did transplantation of single-cell suspensions or spheres alone. Twenty-three days after transplantation, the epidermis formed from the cells bound to the spheres was not as thick as the epidermis on wounds covered with split-thickness skin grafts, but significantly thicker than on wounds to which single-cell suspensions, spheres alone or no transplant at all was applied. Furthermore, fluorescence in situ hybridisation revealed that the transplanted keratinocytes, both those adherent to gelatin spheres and those in single-cell suspension, were components of the newly formed epidermis. These findings indicate that application of biodegradable macroporous spheres may prove to be of considerable value in designing cell-based therapies for the treatment of acute and persistent wounds.
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| 2. |
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| 3. |
- Baş, Yağmur, et al.
(författare)
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Preparation and Characterization of Softwood and Hardwood Nanofibril Hydrogels: Toward Wound Dressing Applications
- 2023
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 24:12, s. 5605-5619
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Tidskriftsartikel (refereegranskat)abstract
- Hydrogels of cellulose nanofibrils (CNFs) are promising wound dressing candidates due to their biocompatibility, high water absorption, and transparency. Herein, two different commercially available wood species, softwood and hardwood, were subjected to TEMPO-mediated oxidation to proceed with delignification and oxidation in a one-pot process, and thereafter, nanofibrils were isolated using a high-pressure microfluidizer. Furthermore, transparent nanofibril hydrogel networks were prepared by vacuum filtration. Nanofibril properties and network performance correlated with oxidation were investigated and compared with commercially available TEMPO-oxidized pulp nanofibrils and their networks. Softwood nanofibril hydrogel networks exhibited the best mechanical properties, and in vitro toxicological risk assessment showed no detrimental effect for any of the studied hydrogels on human fibroblast or keratinocyte cells. This study demonstrates a straightforward processing route for direct oxidation of different wood species to obtain nanofibril hydrogels for potential use as wound dressings, with softwood having the most potential.
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| 4. |
- Berglund, Linn, et al.
(författare)
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Self-Assembly of Nanocellulose Hydrogels Mimicking Bacterial Cellulose for Wound Dressing Applications
- 2023
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 24:5, s. 2264-2277
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Tidskriftsartikel (refereegranskat)abstract
- The self-assembly of nanocellulose in the form of cellulose nanofibers (CNFs) can be accomplished via hydrogen-bonding assistance into completely bio-based hydrogels. This study aimed to use the intrinsic properties of CNFs, such as their ability to form strong networks and high absorption capacity and exploit them in the sustainable development of effective wound dressing materials. First, TEMPO-oxidized CNFs were separated directly from wood (W-CNFs) and compared with CNFs separated from wood pulp (P-CNFs). Second, two approaches were evaluated for hydrogel self-assembly from W-CNFs, where water was removed from the suspensions via evaporation through suspension casting (SC) or vacuum-assisted filtration (VF). Third, the W-CNF-VF hydrogel was compared to commercial bacterial cellulose (BC). The study demonstrates that the self-assembly via VF of nanocellulose hydrogels from wood was the most promising material as wound dressing and displayed comparable properties to that of BC and strength to that of soft tissue.
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| 5. |
- Eskilson, Olof, 1992-, et al.
(författare)
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Nanocellulose composite wound dressings for real-time pH wound monitoring
- 2023
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Ingår i: Materials Today Bio. - : Elsevier. - 2590-0064. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- The skin is the largest organ of the human body. Wounds disrupt the functions of the skin and can have catastrophic consequences for an individual resulting in significant morbidity and mortality. Wound infections are common and can substantially delay healing and can result in non-healing wounds and sepsis. Early diagnosis and treatment of infection reduce risk of complications and support wound healing. Methods for monitoring of wound pH can facilitate early detection of infection. Here we show a novel strategy for integrating pH sensing capabilities in state-of-the-art hydrogel-based wound dressings fabricated from bacterial nanocellulose (BC). A high surface area material was developed by self-assembly of mesoporous silica nanoparticles (MSNs) in BC. By encapsulating a pH-responsive dye in the MSNs, wound dressings for continuous pH sensing with spatiotemporal resolution were developed. The pH responsive BC-based nanocomposites demonstrated excellent wound dressing properties, with respect to conformability, mechanical properties, and water vapor transmission rate. In addition to facilitating rapid colorimetric assessment of wound pH, this strategy for generating functional BC-MSN nanocomposites can be further be adapted for encapsulation and release of bioactive compounds for treatment of hard-to-heal wounds, enabling development of novel wound care materials.
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| 6. |
- Junker, Johan, 1980-, et al.
(författare)
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Adipogenic, Chondrogenic and Osteogenic Differentiation of ClonallyDerived Human Dermal Fibroblasts
- 2010
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Ingår i: Cells Tissues Organs. - Basel : Karger AG. - 1422-6405 .- 1422-6421. ; 191:2, s. 105-118
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Tidskriftsartikel (refereegranskat)abstract
- The apparent need of an autologous cell source for tissueengineering applications has led researchers to explore thepresence of cells with stem cell plasticity in several humantissues. Dermal fibroblasts (FBs) are easy to harvest, expandin vitro and store, rendering them plausible candidates forcell-based therapies. The aim of the present study was toobserve the effects of adipogenic, chondrogenic and osteogenicinduction media on the phenotype of human FBs.Human preadipocytes obtained from fat tissue have beenproposed as an adult stem cell source with suitable characteristics,and were used as control cells in regard to their differentiationpotential. Routine staining, immunohistochemicalanalysis and alkaline phosphatase assay were employed,in order to study the phenotypic shift. FBs were shown topossess multilineage potential, giving rise to fat-, cartilageandbone-like cells. To exclude contaminant progenitor cellsor cell fusion giving rise to tissue with adipocyte-, chondrocyte-and osteoblast-like cells, single-cell cloning was performed.Single-cell-cloned FBs (sccFBs) displayed a similardifferentiation potential as primary-culture FBs. The pres-ence of ‘stem-cell-specific’ surface antigens was analyzedusing flow cytometry. The results reveal that sccFBs haveseveral of the markers associated with cells exhibiting stemcell plasticity. The findings presented here are corroboratedby the findings of other groups, and suggest the use of humandermal FBs in cell-based therapies for the reconstructionof fat, cartilage and bone.
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| 7. |
- Junker, Johan, 1980-, et al.
(författare)
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Gene Expression Analysis of Adipogenic, Chondrogenic and Osteogenic Induced Human Dermal Fibroblasts
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The use of adult stem cells in tissue engineering applications is a promising alternativewhen the possibility of acquiring autologous cells for transplantation is limited. Even so, theadult stem cell populations identified up to this point are far from optimal in aspects ofharvest and culture expansion. With the recent suggestion of stem cell plasticity inherent inhuman dermal fibroblasts, a new plausible candidate for use as cell source in tissuereconstruction has emerged. Fibroblast cultures can be induced to differentiate towardsadipocyte, chondrocyte and osteoblast-like cells in vitro, by the use of induction media. Thepresent works utilizes Affymetrix full expression micro array to identify if genes commonlyexpressed in stem cells differentiating towards the above-mentioned lineages also areexpressed in induced fibroblasts. Several genes important for differentiation andmaintenance of an adipose, cartilage or bone phenotype were found up-regulated in theinduced cultures. The results presented here provide further evidence for the plasticity ofhuman dermal fibroblasts, and their possible use in tissue engineering and reconstructivesurgery.
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| 8. |
- Junker, Johan, 1980-
(författare)
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Human Dermal Fibroblasts in Tissue Engineering
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The loss or failure of tissues and/or organs is one of the most frequent problems in modern healthcare. The field of tissue engineering applies the principles of biology and engineering in order to develop functional substitutes for damaged tissues. Tissue engineering contains elements of medicine, material science and engineering with major components in focus being cells, biomaterials and soluble factors. All three components may be required for the development of clinical treatments.The usage of autologous tissue specific cells for clinical treatment is often not feasible due to poor growth kinetics or unstable phenotypes of the cells. Furthermore, lack of availability of healthy tissue that can be biopsied is a major problem in many applications. One approach to overcome this problem is to use adult stem cells which have the capacity to give rise to several different cell types. Although promising, adult stem cells have major impediments for use in several tissue engineering applications. The difficulties associated with harvest, culture and storage render problems in the development of clinically relevant procedures.During the last years, the inherent plasticity of differentiated somatic cells has been demonstrated. One of the easiest human cell types to obtain, expand and store is the dermal fibroblast. Recent reports indicate that dermal fibroblasts can be induced to differentiate towards several distinct mesenchymal lineages in vitro.The main aim of this thesis was to investigate the inherent stem cell plasticity of human dermal fibroblasts and explore their possible usefulness in tissue engineering applications. The papers included in this thesis employ routine and immunohistochemical staining, enzyme activity assay, analysis of low density lipoprotein incorporation, capillary-like network formation assay and full expression micro array analysis.Fibroblasts were shown to differentiate towards adipocyte, chondrocyte, endothelial and osteoblast-like cell types in vitro. The differentiation from fibroblasts to myofibroblasts in burn scar tissue upon stimulation by mechanical tension was also demonstrated. Adipogenic, chondrogenic and osteogenic induced fibroblasts display the upregulation of several genes associated with adipocytes, chondrocytes and osteoblasts.
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| 9. |
- Junker, Johan P E, 1980-, et al.
(författare)
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Mechanical tension stimulates the transdifferentiation of fibroblasts into myofibroblasts in human burn scars
- 2008
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Ingår i: Burns : journal of the International Society for Burn Injuries. - : Elsevier BV. - 1879-1409. ; 34:7, s. 942-6
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Tidskriftsartikel (refereegranskat)abstract
- Scar formation as a result of burn wounds leads to contraction of the formed granulation tissue, which causes both aesthetic and functional impairment for the patient. Currently, the main treatment methods focus on stretching to prevent tissue contraction. The myofibroblasts play a key role in the contraction of granulation tissue during scar formation, but their presence should normally decrease after wound re-epithelialization. In hypertrophic scars the myofibroblasts persist and is believed to cause further hypertrophy. Previous studies have shown that mechanical tension leads to increased myofibroblast numbers in granulation tissue. In order to evaluate the effect mechanical tension as a result of stretching has on the number of myofibroblasts in burn wound scars, an in vitro model was used. This model used human burn scar biopsies which were stretched and examined after 1 and 6 days to evaluate the effect on the number of myofibroblasts. The stretching caused an increase in the number of myofibroblasts after mechanical stimulation. This indicates that mechanical stimulation using stretching induces fibroblast to myofibroblast transdifferentiation, thus underlining the importance of further investigations of optimal methods of this regime for treating burn scars.
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| 10. |
- Junker, Johan, 1980-, et al.
(författare)
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Prehospital Monitoring of Vital Parameters Using a Novel Device - RespiHeart
- 2017
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Ingår i: Prehospital and Disaster Medicine. - : Cambridge University Press. - 1049-023X .- 1945-1938. ; 32:Suppl. 1, s. S165-S166
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Tidskriftsartikel (refereegranskat)abstract
- Study/Objective: The study aims at validating a novel device (RespiHeart) for monitoring vital parameters in traumatically injured patients. Background: There is a need for a simple-to-use method for monitoring of vital parameters in the prehospital setting. RespiHeart is a small medical device that is attached to the sternum. It sends light of defined wavelengths into the underlying vasculature, and measures the reflected light. The resulting signals are then treated using proprietary algorithms to obtain heart rate and respiratory rate. The device has the capability to also measure oxygen saturation, temperature and movement. Methods: The device was tested during training sessions for medical personnel, where various traumatic wounds were inflicted on anesthetized pigs. The training was primarily focused on teaching acute lifesaving interventions. The RespiHeart device was applied to the animal and used to monitor vital parameters throughout the training session. A total of 22 animals were included in the study. The data gathered from Respiheart were compared to results from a pulse oximeter and ventilator connected to the animal. Statistical comparison were performed using linear regression and Bland-Altman plots to analyze agreement of methods. Results: The heart rate as measured by the pulse oximeter was correlated to the rate reported by RespiHeart. The R2 was 0.9946 with a p-value of less than 0.0001. Bland-Altman analysis of heart rate revealed a bias of -0.06127 (95% CI -2.219- 2.097). The respiratory rate as set on the ventilator was correlated to the rate reported by RespiHeart. The R2 was 0.9978 with a p-value of less than 0.0001. Bland-Altman analysis of respiratory rate revealed a bias of -0.008584 (95% CI -0.42-0.4028). Conclusion: The results obtained in this study demonstrate a high degree of correlation between the data obtained from RespiHeart and the pulse oximeter and ventilator. This renders RespiHeart as a promising device for prehospital use.
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| 11. |
- Junker, Johan, 1980-, et al.
(författare)
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Standardized Measurement of Capillary Refill Time using Novel Technology
- 2019
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Ingår i: Prehospital and Disaster Medicine. - : Cambridge University Press. - 1049-023X .- 1945-1938. ; 34:s1, s. 167-168
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: In a patient going into shock, blood is redistributed from the periphery to the central circulation, making an assessment of skin perfusion useful in a prehospital setting. Capillary refill time (CRT) is the time required for a pressure blanched skin site to reperfuse. Currently, CRT is tested by manually applying pressure for 5s to the skin and observing the time before reperfusion. Guidelines state that CRT should be 2-3s in a healthy patient. Shortcomings in this procedure include lack of standardization of pressure, subjective assessment of the time for reperfusion, and not accounting for the patient’s skin temperature.Aim: To develop a standardized objective procedure for testing CRT in the prehospital setting.Method: The study protocol was approved by the Ethics Committee at Linköping University (M200-07, 2015-99-31). An electro-pneumatic device exerting constant force (9N) over 5s was developed. CRT was measured using the Tissue Viability Imager (Wheelsbridge AB, Sweden) which relies on polarization spectroscopy. To simulate hypothermic conditions, healthy volunteers were subjected to low ambient temperature (8°C). Blood loss was simulated using a custom-built lower body negative pressure (LBNP) chamber. In both scenarios, the CRT test was carried out on three test sites (finger pulp, forehead, and sternum).Results: CRT on the finger pulp and sternum was shown to be increased following the hypothermic conditions, but not on the forehead. Skin temperature on the three sites followed the same pattern, with the forehead being virtually unchanged. Tests performed during LBNP revealed an apparent effect on CRT following the simulated blood loss, with prolonged CRT for all sites tested.Discussion: A successful methodology for objective assessment of CRT was developed, which was validated on healthy volunteers following hypothermia or simulated blood loss. Ongoing work will investigate a combination of hypothermia and blood loss to more accurately simulate the prehospital setting.
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| 12. |
- Karlsson, Lisa K, et al.
(författare)
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Human Dermal Fibroblasts : A Potential Cell Source for Endothelialization of Vascular Grafts
- 2009
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Ingår i: Annals of Vascular Surgery. - : Elsevier BV. - 0890-5096 .- 1615-5947. ; 23:5, s. 663-674
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Recently, there has been an intense ongoing search for suitable cell sources for vascular tissue engineering. Previous studies report that cells with multilineage potential have been found within the connective stroma of the skin. In line with this, preliminary data from our group suggest that human dermal fibroblasts have the capacity to alter their phenotype into an endothelial cell-like phenotype in vitro. As a first step in using these cells in vascular tissue engineering, we investigated their ability to form an endothelial cell-like layer on a scaffold in vitro. Furthermore, we studied the possibility of seeding dermal fibroblasts on a scaffold and later commencing with induction toward an endothelial cell-like phenotype. METHODS: Cells cultured in either normal fibroblast medium or endothelial induction medium were seeded on a gelatin-based scaffold. To study the organization of cells, routine staining was performed. Differentiation was confirmed by Western blotting and immunohistochemistry with antibodies directed toward molecules commonly used to identify endothelial cells. RESULTS AND CONCLUSION: Our data support that human dermal fibroblasts differentiated toward endothelial cell-like cells prior to seeding showed histological resemblance to mature endothelial cells, while fibroblasts seeded and later induced into endothelial differentiation grew in multilayer. However, expression of various surface molecules indicative of an endothelial phenotype was seen using both techniques. In conclusion, the results presented in this study indicate that human dermal fibroblasts differentiated toward an endothelial cell-like phenotype may be a novel cell source for endothelialization of vascular grafts.
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| 13. |
- Karlsson, Lisa K., et al.
(författare)
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Human Dermal Fibroblasts and Single-Cell Clone Fibroblasts Have theCapacity to Alter Their Phenotype Towardsan Endothelial-Like Cell type
- 2009
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Ingår i: European Cells & Materials. - 1473-2262.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We investigated the capacity of normal human dermal fibroblasts to alter their phenotype into an endothelialcell-like phenotype. By utilising in vitro cell culture models, the part played by different types of serum andmedium constituents in inducing a phenotypic change of fibroblasts was investigated. The experiments usedprimary cultures of human endothelial cells, human dermal fibroblasts and single-cell clone fibroblasts. Thelatter cell type was obtained by clonal expansion using a micromanipulator technique. The results showed thatthe presence of human serum in the cell culture medium caused both types of fibroblasts to express vonWillebrand factor, to incorporate fluorochrome-labelled LDL, and to start forming capillary-like networks in asimilar way to endothelial cells. The phenotypic shift was detectable after 4 days of cell culture and reached amaximum after 7-10 days. To our knowledge this is the first report to describe differentiation of humanfibroblasts towards an endothelial cell-like phenotype. The results also show that the underlying mechanism ofthe phenotypic shift is a change in gene expression in the dermal fibroblasts and not fusion between different celltypes. Collectively, the present results indicate that human dermal fibroblasts may be a novel cell source forcreating vascular endothelium.
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| 14. |
- Lampi, Maria, 1967-, et al.
(författare)
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Potential benefits of triage for the trauma patient in a Kenyan emergency department
- 2018
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Ingår i: BMC Emergency Medicine. - : Springer. - 1471-227X. ; 18
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundImproved trauma management can reduce the time between injury and medical interventions, thus decreasing morbidity and mortality. Triage at the emergency department is essential to ensure prioritization and timely assessment of injured patients. The aim of the present study was to investigate how a lack of formal triage system impacts timely intervention and mortality in a sub-Saharan referral hospital. Further, the study attempts to assess potential benefits of triage towards efficient management of trauma patients in one middle income country.MethodsA prospective descriptive study was conducted. Adult trauma patients admitted to the emergency department during an 8-month period at Moi Teaching and Referral Hospital in Eldoret, Kenya, were included. Mode of arrival and vital parameters were registered. Variables included in the analysis were Injury Severity Score, time before physician’s assessment, length of hospital stay, and mortality. The patients were retrospectively categorized according to the Rapid Emergency Triage and Treatment System (RETTS) from patient records.ResultsA total of 571 patients were analyzed, with a mean Injury Severity Score of 12.2 (SD 7.7) with a mean length of stay of 11.6 (SD 18.3) days. The mortality rate was 1.8%. The results obtained in this study illustrate that trauma patients admitted to the emergency department at Eldoret are not assessed in a timely fashion, and the time frame recommendations postulated by RETTS are not adhered to. Assessment of patients according to the triage algorithm used revealed a significantly higher average Injury Severity Score in the red category than in the other color categories.ConclusionThe results from this study clearly illustrate a lack of correct prioritization of patients in relation to the need for timely assessment. This is further demonstrated by the retrospective triage classification of patients, which identified patients with high ISS as in urgent need of care. Since no significant difference in to time to assessment regardless of injury severity was observed, the need for a well-functioning triage system is apparent.
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| 15. |
- Lampi, Maria, et al.
(författare)
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Pre-hospital triage performance after standardized trauma courses
- 2017
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Ingår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. - : BIOMED CENTRAL LTD. - 1757-7241. ; 25
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Tidskriftsartikel (refereegranskat)abstract
- Background: The pre-hospital triage process aims at identifying and prioritizing patients in the need of prompt intervention and/or evacuation. The objective of the present study was to evaluate triage decision skills in a Mass Casualty Incident drill. The study compares two groups of participants in Advanced Trauma Life Support and Pre-Hospital Trauma Life Support courses. Methods: A questionnaire was used to deal with three components of triage of victims in a Mass Casualty Incident: decision-making; prioritization of 15 hypothetical casualties involved in a bus crash; and prioritization for evacuation. Swedish Advanced Trauma Life Support and Pre-Hospital Trauma Life Support course participants filled in the same triage skills questionnaire just before and after their respective course. Results: One hundred fifty-three advanced Trauma Life Support course participants were compared to 175 Pre-Hospital Trauma Life Support course participants. The response rates were 90% and 95%, respectively. A significant improvement was found between pre-test and post-test for the Pre-Hospital Trauma Life Support group in regards to decision-making. This difference was only noticeable among the participants who had previously participated in Mass Casualty Incident drills or had experience of a real event (pre-test mean +/- standard deviation 2.4 +/- 0.68, post-test mean +/- standard deviation 2.60 +/- 0.59, P = 0.04). No improvement was found between pre-test and post-test for either group regarding prioritization of the bus crash casualties or the correct identification of the most injured patients for immediate evacuation. Conclusions: Neither Advanced Trauma Life Support nor Pre-Hospital Trauma Life Support participants showed general improvement in their tested triage skills. However, participation in Mass Casualty Incident drills or experience of real events prior to the test performed here, were shown to be advantageous for Pre-Hospital Trauma Life Support participants. These courses should be modified in order to assure proper training in triage skills.
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| 16. |
- Muhrbeck, Måns, et al.
(författare)
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Efficacy of topical honey compared to systemic gentamicin for treatment of infected war wounds in a porcine model : A non-inferiority experimental pilot study
- 2022
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Ingår i: Injury. - : Elsevier. - 0020-1383 .- 1879-0267. ; 53:2, s. 381-392
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Tidskriftsartikel (refereegranskat)abstract
- Background: In armed conflicts, infected wounds constitute a large portion of the surgical workload. Treatment consists of debridements, change of dressings, and antibiotics. Many surgeons advocate for the use of honey as an adjunct with the rationale that honey has bactericidal and hyperosmotic properties. However, according to a Cochrane review from 2015 there is insufficient data to draw any conclusions regarding the efficacy of honey in treatment of wounds. We, therefore, decided to evaluate if honey is non-inferior to gentamicin in the treatment of infected wounds in a highly translatable porcine wound model. Material and methods: 50 standardized wounds on two pigs were infected with S. aureus and separately treated with either topically applied Manuka honey or intramuscular gentamicin for eight days. Treatment efficacy was evaluated with quantitative cultures, wound area measurements, histological, immunohistochemical assays, and inflammatory response. Results: Topically applied Manuka honey did not reduce bacterial count or wound area for the duration of treatment. Intramuscular gentamicin initially reduced bacterial count (geometric mean 5.59*,0.37 - 4.27 *,0.80 log10 (GSD) CFU/g), but this was not sustained for the duration of the treatment. However, wound area was significantly reduced with intramuscular gentamicin at the end of treatment (mean 112.8 +/- 30.0-67.7 +/- 13.2 (SD) mm(2)). ANOVA-analysis demonstrated no variation in bacterial count for the two treatments but significant variation in wound area (p = 0.0001). The inflammatory response was more persistent in the pig with wounds treated with topically applied Manuka honey than in the pig treated with intramuscular gentamicin. Conclusion: At the end of treatment S. aureus count was the same with topically applied Manuka honey and intramuscular gentamicin. The wound area was unchanged with topically applied Manuka honey and decreased with intramuscular gentamicin. Topically applied Manuka honey could consequently be non inferior to intramuscular gentamicin in reducing S. aureus colonization on the wounds surface, but not in reducing wound size. The use of Manuka honey dressings to prevent further progression of a wound infection may therefore be of value in armed conflicts, where definite care is not immediately available.
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| 17. |
- (Svensson) Nyman, Erika, 1976-, et al.
(författare)
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Effects of amniotic fluid on human keratinocyte gene expression : Implications for wound healing
- 2022
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Ingår i: Experimental dermatology. - Chichester, United Kingdom : Wiley-Blackwell. - 0906-6705 .- 1600-0625. ; 31:5, s. 764-774
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Tidskriftsartikel (refereegranskat)abstract
- Cutaneous wounds can lead to huge suffering for patients. Early fetal wounds have the capacity to regenerate without scar formation. Amniotic fluid (AF), containing hyaluronic acid (HA), may contribute to this regenerative environment. We aimed to analyse changes in gene expression when human keratinocytes are exposed to AF or HA. Human keratinocytes were cultured to subconfluence, starved for 12 h and then randomised to be maintained in (1) Dulbeccos modified Eagles medium (DMEM), (2) DMEM with 50% AF, or (3) DMEM with 50% fetal calf serum (FCS). Transcriptional changes were analysed using microarray and enriched with WebGestalt and Enrichr. Additionally, eight diagnostic genes were analysed using semiquantitative real-time PCR to investigate epidermal differentiation and cellular stress after HA exposure as an alternative for AF exposure. The AF and FCS treatments resulted in enrichment of genes relating to varied aspects of epidermal and keratinocyte biology. In particular, p63-, AP1- and NFE2L2- (Nrf2) associated genes were found significantly regulated in both treatments. More genes regulated by FCS treatment were associated with inflammatory signalling, whilst AF treatment was dominantly associated with molecular establishment of epidermis and lipid metabolic activity. HA exposure mostly resulted in gene regulation that was congruent with the AF microarray group, with increased expression of ITGA6 and LOR. We conclude that AF exposure enhances keratinocyte differentiation in vitro, which suggests that AF constituents can be beneficial for wound-healing applications.
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| 18. |
- Toll John, Rani, 1975-, et al.
(författare)
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A cool response : the influence of ambient temperature on capillary refill time
- 2018
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Ingår i: Journal of Biophotonics. - : Wiley-VCH Verlagsgesellschaft. - 1864-063X .- 1864-0648. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- ObjectiveTo describe the effect of low ambient temperature on skin temperature and capillary refill (CR) time in forehead, sternum and finger pulp.MethodsAn observational, nonrandomized experimental study on 15 healthy subjects (6 females) in a cold room (8°C). Outcome measures were skin temperature and quantified CR test after application of a standardized blanching pressure (9 N/cm2) using digital photographic polarization spectroscopy to generate CR times.ResultsThe finger pulp showed marked temperature fall and prolonged CR times (>10 seconds). The CR registrations of the forehead and sternum were more comparable to curves observed in a control material at room temperature, and skin temperature falls were less marked. CR times were not prolonged in forehead measurements. At the sternum, some individuals showed CR times beyond guideline recommendations despite only a marginal reduction in skin temperature.ConclusionsLow ambient temperature is a strong independent factor for CR time at peripheral sites. Reservation about sternum as a site of measurement is warranted since cold provocation produced prolonged CR times in some individuals. We found that the forehead is the most thermostable of the 3 sites and thus the preferred site to avoid ambient temperature artifact in measuring CR time.
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