Removal of necrotic tissue is a vital step in the treatment of full-thickness burn wounds, with surgical debridement being the most effective method. Since minor burn wounds are typically treated on ...an outpatient basis where surgical capabilities can be limited there is a need for alternative treatment options. In this study we aim to evaluate the use of amino acid buffered hypochlorite (AABH) as a chemical enhancement for wound debridement in a porcine infected burn wound model.
A total of 60 full-thickness burn wounds, 3 cm in diameter, were created on four pigs using a standardized burn device. The wounds were inoculated with 107 colony-forming units (CFU) of S. aureus. The experimental groups included wounds debrided with a plastic curette, wounds debrided after pretreatment with AABH, and control wounds wiped with gauze. Wounds were treated twice per week for three weeks. Debridement, healing, and infection parameters were evaluated over time.
After one week, but not after two and three weeks, the curette and AABH groups had higher debrided weights compared to control (p < 0.05). Percentage of wound area adequately cleared from necrotic tissue was higher in the AABH-group compared to the curette-group and control, after one week. The earliest healing was measured in the AABH group after two weeks (5 % of wounds), which also had the most healed wounds after three weeks (55 %). In both the AABH and the curette groups, bacterial load had fallen below 105 CFU/g after two weeks. No CFU were detectable in the AABH group after three weeks. The AABH-group was also the easiest to debride.
Our results indicate that AABH facilitates wound debridement and could be a helpful addition to an effective treatment modality for removal of necrotic tissue in full-thickness burns.
•Successful debridement of burns improve healing and reduce infection.•Treatment with amino acid buffered hypochlorite facilitates debridement of burns.•A porcine infected burn model is suitable for translational studies of debridement.
The molecular mechanism of Salinomycin's toxicity is not fully understood. Various studies reported that Ca2+, cytochrome c, and caspase activation play a role in Salinomycin-induced cytotoxicity. ...Furthermore, Salinomycin may target Wnt/β-catenin signaling pathway to promote differentiation and thus elimination of cancer stem cells. In this study, we show a massive autophagic response to Salinomycin (substantially stronger than to commonly used autophagic inducer Rapamycin) in prostrate-, breast cancer cells, and to lesser degree in human normal dermal fibroblasts. Interestingly, autophagy induced by Salinomycin is a cell protective mechanism in all tested cancer cell lines. Furthermore, Salinomycin induces mitophagy, mitoptosis and increased mitochondrial membrane potential (∆Ψ) in a subpopulation of cells. Salinomycin strongly, and in time-dependent manner decreases cellular ATP level. Contrastingly, human normal dermal fibroblasts treated with Salinomycin show some initial decrease in mitochondrial mass, however they are largely resistant to Salinomycin-triggered ATP-depletion. Our data provide new insight into the molecular mechanism of preferential toxicity of Salinomycin towards cancer cells, and suggest possible clinical application of Salinomycin in combination with autophagy inhibitors (i.e. clinically-used Chloroquine). Furthermore, we discuss preferential Salinomycins toxicity in the context of Warburg effect.
•We show how Salinomycin, that preferentially kills cancer stem cells, achieves it.•We show how Salinomycin discriminates between normal and cancer cells.•We set Salinomycin's action in the context of energy metabolism in cancer cells.•We employ diverse methods, and cells deficient in genes of interest.•Salinomycin may be combined with autophagy inhibitors for cancer treatment.
BACKGROUND:Hyaluronic acid (HA), a large glycosaminoglycan involved in proliferation, migration, and tissue repair, is suggested to be an important factor for keratinocyte activation and ...re-epithelialization. The experimental hypothesis of this study was that HA accelerates re-epithelialization, and we aimed to investigate the effect of exogenous intradermal HA during deep dermal, incisional wound healing in vivo in humans, the primary endpoint being re-epithelialization.
METHODS:A total of 8 standardized deep dermal incisional wounds (depth 1.6 mm, width 1.8 mm) per subject were induced in 10 healthy volunteers. Two of the wound sites per subject were pretreated with injections of HA and 2 with saline solution. At 2 time points (24 hours and 14 days), 2 biopsies for each treatment group (one for histology and one for proteomics) were taken. Skin erythema was measured at 24-hour intervals for 14 days as a surrogate measurement of inflammation.
RESULTS:At 24 hours, 8 of 9 wounds pretreated with HA showed complete re-epithelization, whereas none of the wounds pretreated with saline had re-epithelized. Wounds pretreated with HA also showed a 10-fold regulation of 8 identified proteins involved in wound healing compared to wounds treated with saline solution. No difference in inflammation, as measured as erythema, could be seen between any of the groups.
CONCLUSIONS:We conclude that HA accelerates re-epithelialization and stimulates an altered protein expression in vivo in human deep dermal incisional skin wounds, but has no effect on the inflammation process as measured by erythema.
The possibility to use a suspended tridimensional matrix as scaffolding for re-epithelialization of in vitro cutaneous wounds was investigated with the aid of a human in vitro wound healing model ...based on viable full thickness skin. Macroporous gelatin microcarriers, CultiSpher-S, were applied to in vitro wounds and cultured for 21 days. Tissue sections showed incorporation of wound edge keratinocytes into the microcarriers and thicker neoepidermis in wounds treated with microcarriers. Thickness of the neoepidermis was measured digitally, using immunohistochemical staining of keratins as epithelial demarcation. Air-lifting of wounds enhanced stratification in control wounds as well as wounds with CultiSpher-S. Immunohistochemical staining revealed expression of keratin 5, keratin 10, and laminin 5 in the neoepidermal component. We conclude that the CultiSpher-S microcarriers can function as tissue guiding scaffold for re-epithelialization of cutaneous wounds.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: A person diagnosed with gender dysphoria who was assigned female at birth (AFAB) may request a vaginectomy as part of gender-affirming treatment. The aim of this study was to investigate ...the impact of vaginectomy on symptoms of pelvic floor dysfunction (PFD). Methods: This is a cohort study on patient-reported symptoms of PFD in patients who were AFAB, diagnosed with gender dysphoria, and undergoing vaginectomy in a single surgical center. Patients responded to a questionnaire preoperatively and 1 year postoperatively. The questionnaire consisted of 33 questions, including a modified short-form version of the Pelvic Floor Distress Inventory (PFDI-20). Results: Twenty-three consecutive patients were included in the study and 20 patients (87%) completed the 1-year follow-up. The preoperative median PFDI-20 score was 24 (0–114) compared with 32 (0–168) at the 1-year follow-up ( P = 0.07). Patients who had previously undergone neophallus construction with a metoidioplasty (n = 15) had no significant change between the preoperative and the 1-year postoperative PFDI-20 score median 17.5 (0–114) and 27.5 (0–145) ( P = 0.65), respectively; whereas those with a groin flap phalloplasty (n = 5) had a significant increase in reported symptoms median 37 (10–95) and 124 (45–168), respectively ( P = 0.04). Conclusions: Overall, vaginectomy could be performed without any major impact on symptoms of PFD. However, this seemed to be true mainly for patients with previous metoidioplasty, whereas patients with previous groin flap phalloplasty reported worsening of symptoms.
The human cathelicidin anti-microbial protein, hCAP18 is a component of the innate immune system and has broad anti-microbial activity conferred by its C-terminal fragment LL-37. hCAP18 is ...constitutively produced in leukocytes and is induced in barrier organs upon inflammation and infection. We demonstrate here a novel role for this peptide in re-epithelialization of skin wounds. We show that high levels of hCAP18 are produced in skin in vivo upon wounding. The highest hCAP18 levels are attained at 48h post-injury, declining to pre-injury levels upon wound closure. hCAP18 is detected in the inflammatory infiltrate and in the epithelium migrating over the wound bed. In chronic ulcers, however, hCAP18 levels are low and immunoreactivity for hCAP18/LL-37 is absent in ulcer edge epithelium. Using a noninflammatory ex vivo wound healing model, composed of organ-cultured human skin, we show that hCAP18 is strongly expressed in healing skin epithelium, and that treatment with antibodies raised and affinity purified against LL-37, inhibits re-epithelialization in a concentration-dependent manner. Immunoreactivity for the proliferation marker Ki67 is absent in the epithelium of such inhibited wounds, suggesting that LL-37 may play a part in epithelial cell proliferation. Thus, we suggest that, in addition to being an anti-microbial peptide, LL-37 also plays a part in wound closure and that its reduction in chronic wounds impairs re-epithelialization and may contribute to their failure to heal.
The treatment of burn wounds and hypopigmentation conditions often require autologous transplantation of keratinocytes and melanocytes. Tracking transplanted cells to ascertain their contribution to ...tissue recapitulation presents a challenge. This study demonstrates a methodology based on passive staining with carboxyfluorescein hydroxysuccinimidyl ester (CFSE) that enables localization of cells in tissue sections to investigate the fate of transplanted cells in wound re-epithelialisation.
Viability and migration of CFSE-stained keratinocytes and melanocytes were investigated using viability staining and scratch assays, while proliferation of cells was measured using flow cytometry. In addition, CFSE-stained keratinocytes and melanocytes were transplanted to a human ex vivo wound model, either in suspension, or with the aid of macroporous gelatine microcarriers. Wounds were analysed seven, 14 and 21 days post transplantation using cryosectioning and fluorescence microscopy. Sections from wounds with transplanted co-cultured keratinocytes and melanocytes were stained for pancytokeratin to distinguish keratinocytes.
CFSE-staining of keratinocytes and melanocytes did not affect the viability, migration or proliferation of the cells. Transplanted cells were tracked in ex vivo wounds for 21 days, illustrating that the staining had no effect on wound re-epithelialisation. In conclusion, this study presents a novel application of CFSE-staining for tacking transplanted primary human keratinocytes and melanocytes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The apparent need of an autologous cell source for tissue engineering applications has led researchers to explore the presence of cells with stem cell plasticity in several human tissues. Dermal ...fibroblasts (FBs) are easy to harvest, expand in vitro and store, rendering them plausible candidates for cell-based therapies. The aim of the present study was to observe the effects of adipogenic, chondrogenic and osteogenic induction media on the phenotype of human FBs. Human preadipocytes obtained from fat tissue have been proposed as an adult stem cell source with suitable characteristics, and were used as control cells in regard to their differentiation potential. Routine staining, immunohistochemical analysis and alkaline phosphatase assay were employed, in order to study the phenotypic shift. FBs were shown to possess multilineage potential, giving rise to fat-, cartilage- and bone-like cells. To exclude contaminant progenitor cells or 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 similar differentiation potential as primary-culture FBs. The presence of 'stem-cell-specific' surface antigens was analyzed using flow cytometry. The results reveal that sccFBs have several of the markers associated with cells exhibiting stem cell plasticity. The findings presented here are corroborated by the findings of other groups, and suggest the use of human dermal FBs in cell-based therapies for the reconstruction of fat, cartilage and bone.
Spider silk is an interesting biomaterial for medical applications. Recently, a method for production of recombinant spider silk protein (4RepCT) that forms macroscopic fibres in physiological ...solution was developed. Herein, 4RepCT and MersilkTM (control) fibres were implanted subcutaneously in rats for seven days, without any negative systemic or local reactions. The tissue response, characterised by infiltration of macrophages and multinucleated cells, was similar with both fibres, while only the 4RepCT-fibres supported ingrowth of fibroblasts and newly formed capillaries. This in vivo study indicates that 4RepCT-fibres are well tolerated and could be used for medical applications, e.g., tissue engineering.
Craniopharyngioma is a rare benign intracranial epithelial tumor that, however, often recurs and sometimes kills the affected
patients, one-third of which are children. In many cases, the patients ...acquire growth hormone deficiency and postoperatively
need substitution. Generally, growth hormone promotes local release of insulin-like growth factor I (IGF-I), which in turn
activates the IGF-I receptor (IGF-IR) if present. Together, these circumstances raise the question whether IGF-IR may be involved
in craniopharyngioma growth. To address this issue, we analyzed phenotypically well-characterized primary low-passage craniopharyngioma
cell lines from nine different patients for IGF-IR expression and IGF-I dependency. Two of the cell lines showed no/very low
expression of the receptor and was independent on IGF-I, whereas five cell lines exhibited a strong expression and was clearly
contingent on IGF-I. The two remaining cell lines had low receptor expression and IGF-I dependency. Upon treatment with an
IGF-IR inhibitor, cells with high IGF-IR expression responded promptly with decreased Akt phosphorylation followed by growth
arrest. These responses were not seen in cells with no/very low receptor expression. Growth of cell lines with low IGF-IR
expression was only slightly affected by IGF-IR inhibition. Taken together, our data suggest that IGF-IR may be involved in
the growth of a subset of craniopharyngiomas and points to the possibility of the involvement of IGF-IR inhibitors as a treatment
modality to obtain complete tumor-free conditions before growth hormone substitution.
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