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Synthetic mimics of antimicrobial peptides (AMPs) is a promising class of molecules for a variety of antimicrobial applications. Several hurdles must be passed before effective systemic infection therapies with AMPs can be achieved, but the path to effective topical treatment of skin, nail, and soft tissue infections appears less challenging to navigate. Skin and soft tissue infection is closely coupled to the emergence of antibiotic resistance and represents a major burden to the healthcare system. The present study evaluates the promising synthetic cationic AMP mimic, AMC-109, for treatment of skin infections in vivo. The compound is evaluated both in impregnated cotton wound dressings and in a gel formulation against skin infections caused by Staphylococcus aureus and methicillin resistant S. aureus. Both the ability to prevent colonization and formation of an infection, as well as eradicate an ongoing infection in vivo with a high bacterial load, were evaluated. The present work demonstrates that AMC-109 displays a significantly higher antibacterial activity with up to a seven-log reduction in bacterial loads compared to current clinical standard therapy; Altargo cream (1% retapamulin) and Fucidin cream (2% fusidic acid) in the in vivo wound models. It is thus concluded that AMC-109 represents a promising entry in the development of new and effective remedies for various skin infections.

Background Colorectal cancer is the second most common cause of cancer‐related death worldwide and standardized therapies often fail to treat the more aggressive and progressive types of colorectal cancer. Tumor cell heterogeneity and influence from the surrounding tumor microenvironment (TME) contribute to the complexity of the disease and large variability in clinical outcomes. Methods To model the heterogeneous nature of colorectal cancer, we used patient‐derived scaffolds (PDS), which were obtained via decellularization of surgically resected tumor material, as a growth substrate for standardized cell lines. Results After confirmation of native cell absence and validation of the structural and compositional integrity of the matrix, 89 colorectal PDS were repopulated with colon cancer cell line HT29. After 3 weeks of PDS culture, HT29 cells varied their gene and protein expression profiles considerably compared to 2D‐grown HT29 cells. Markers associated with proliferation were consistently decreased, while markers associated with pluripotency were increased in PDS‐grown cells compared to their 2D counterparts. When comparing the PDS‐induced changes in HT29 cells with clinically relevant tumor information from individual patients, we observed significant associations between stemness/pluripotency markers and tumor location, and between epithelial‐to‐mesenchymal transition (EMT) markers and cancer mortality. Kaplan–Meier analysis revealed that low PDS‐induced EMT correlated with worse cancer‐specific survival. Conclusions The colorectal PDS model can be used as a simplified personalized tool that can potentially reveal important diagnostic and pathophysiological information related to the TME., Colorectal patient‐derived scaffolds (PDS) were used as culture substrate for colon cancer cell line HT29. Significant associations were observed between the PDS‐induced changes in gene expression in HT29 cells and important clinical information from individual patients. Therefore, the colorectal PDS model can potentially be used as a simplified personalized tool that can reveal important diagnostic and pathophysiological information related to the tumor microenvironment.

Breast cancer is a heterogeneous disease where the tumor microenvironment, including extracellular components, plays a crucial role in tumor progression, potentially modulating treatment response. Different approaches have been used to develop three‐dimensional models able to recapitulate the complexity of the extracellular matrix. Here, we use cell‐free patient‐derived scaffolds (PDSs) generated from breast cancer samples that were recellularized with cancer cell lines as an in vivo‐like culture system for drug testing. We show that PDS cultured MCF7 cancer cells increased their resistance against the front‐line chemotherapy drugs 5‐fluorouracil, doxorubicin and paclitaxel in comparison to traditional two‐dimensional cell cultures. The gene expression of the environmentally adapted cancer cells was modulated in different ways depending on the drug and the concentration used. High doses of doxorubicin reduced cancer stem cell features, whereas 5‐fluorouracil increased stemness and decreased the proliferative phenotype. By using PDSs repopulated with other breast cancer cell lines, T‐47D and MDA‐MB‐231, we observed both general and cell line specific drug responses. In summary, PDSs can be used to examine the extracellular matrix influence on cancer drug responses and for testing novel compounds in in vivo‐like microenvironments., This article introduces a novel 3D in vivo‐like culture system by using decellularized scaffolds from primary breast cancer samples, which allow to study the influence of the tumor microenvironment in response to chemotherapeutic agents.

We tested the anti-adhesional effect of a new thiol-ene-based coating in a rabbit model. In 12 New Zealand white rabbits, the periosteum and cortex of the proximal phalanx of the second toe of both hind paws was scratched. Stainless steel plates were fixated with screws. One plate was coated with DendroPrime and the other left bare. The non-operated second toes of both hind paws of an additional four rabbits served as controls. Seven weeks after surgery, the soft tissue adhesion to the plates was evaluated macroscopically, and joint mobility was measured biomechanically. Toe joint mobility was about 20% greater and statistically significant in specimens with coated plates compared with the bare plates. Soft tissue overgrowth and, in some cases, synovitis or adhesions between the plate and the tendon were observed on all bare plates but not on any of the coated plates. We conclude that the thiol-ene-based coating can improve joint mobility by about 20%. This material has a potential to reduce adhesion around plates in fracture surgery. © The Author(s) 2020.

PURPOSE:Intermittent catheterization (IC) is a proven effective long-term bladder management strategy for individuals who have lower urinary tract dysfunction. This study provides clinical evidence about multiple-reuse versus single-use catheterization techniques and if catheter choice can have an impact on health-related quality of life (HRQoL). METHOD:A prospective, multi-center, clinical trial studied patients who currently practiced catheter reuse, and who agreed to prospectively evaluate single-use hydrophilic-coated (HC) (i.e. LoFric) catheters for 4 weeks. A validated Intermittent Self-Catheterization Questionnaire (ISC-Q) was used to obtain HRQoL. Reused catheters were collected and studied with regard to microbial and debris contamination. RESULTS:The study included 39 patients who had practiced IC for a mean of 10 years, 6 times daily. At inclusion, all patients reused catheters for a mean of 21 days (SD = 48) per catheter. 36 patients completed the prospective test period and the mean ISC-Q score increased from 58.0 (SD = 22.6) to 67.2 (SD = 17.7) when patients switched to the single-use HC catheters (p = 0.0101). At the end of the study, 83% (95% CI [67-94%]) preferred to continue using single-use HC catheters. All collected reused catheters (100%) were contaminated by debris and 74% (95% CI [58-87%]) were contaminated by microorganisms, some with biofilm. CONCLUSION:Single-use HC catheters improved HRQoL and were preferred over catheter reuse among people practicing IC. Catheter multiple-reuse may pose a potential safety concern due to colonization by microorganisms as well as having reduced acceptance compared to single use. TRIAL REGISTRY NUMBER:ClinicalTrials.gov NCT02129738.

Sugarcane bagasse, an abundant residue, is usually burned as an energy source. However, provided that appropriate and sustainable pulping and fractionation processes are applied, bagasse can be utilized as a main source of cellulose nanofibrils (CNF). We explored in this study the production of CNF inks for 3D printing by direct-ink-writing technology. The CNF were tested against L929 fibroblasts cell line and we confirmed that the CNF from soda bagasse fibers were found not to have a cytotoxic potential. Additionally, we demonstrated that the alginate and Ca 2+ caused significant dimensional changes to the 3D printed constructs. The CNF-alginate grids exhibited a lateral expansion after printing and then shrank due to the cross-linking with the Ca 2+ . The release of Ca 2+ from the CNF and CNF-alginate constructs was quantified thus providing more insight about the CNF as carrier for Ca 2+ . This, combined with 3D printing, offers potential for personalized wound dressing devices, i.e. tailor-made constructs that can be adapted to a specific shape, depending on the characteristics of the wound healing treatment. Fil: Chinga Carrasco, Gary. Research Institutes of Sweden. Paper and Fibre Research Institute; Suecia Fil: Ehman, Nanci Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Filgueira, Daniel. Research Institutes of Sweden. Paper and Fibre Research Institute; Suecia Fil: Johansson, Jenny. Research Institutes of Sweden. Bioscience and Materials; Suecia Fil: Vallejos, María Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Håkansson, Joakim. Research Institutes of Sweden. Bioscience and Materials; Suecia Fil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

Repair of a transected flexor tendon will, despite careful technique and early rehabilitation, usually result in a restricted range of movement. This is mainly because adhesions form between the tendon and the surrounding structures. Our aim was to establish an experimental model in rabbits for future studies on new techniques to reduce the formation of adhesions after zone II repair of flexor tendons. In rabbits' hind paws the metatarsal bones II, IV, and V were removed and the flexor tendon was freed to the metatarsophalangeal (MTP) joint. The digits were secured in a specifically-designed biomechanical testing device comprising a servo-hydraulic actuator that was designed to apply controlled force or displacement. The tests were videotaped with a digital force-monitor behind the tested digit. Paper printouts from the recordings were obtained for 0, 0.5, 1, 2, 3, 4, and 5 Newton (N) and metatarsophalangeal, proximal interphalangeal, and distal interphalangeal, angles and distances between metatarsophalangeal joints and claws were measured. The tensile strength of the tendon was evaluated by a load-to-failure test. The continuous data obtained from the experiments were used to calculate functional stiffness at the selected forces. The model allows for unique continuous recordings of mobility of toes, thereby indirectly quantifying the presence of adhesions and the assessment of tensile strength. The data are reproducible, and there is little variation between the digits tested. The model is primarily intended to compare data among treated and non-treated digits of methods to limit the formation of adhesions after tendons have been repaired.

The urgent need to develop novel antimicrobial therapies has stimulated interest in antimicrobial peptides as therapeutic candidates for the treatment of infectious diseases. The aim of this study was to evaluate the anti-infectious effect of the synthetic antimicrobial peptide PXL150, formulated in hydroxypropyl cellulose (HPC) gel, on Pseudomonas aeruginosa in vitro and in an in vivo mouse model of infected burn wounds as well as to assess the in vivo safety profile of PXL150 in rats and rabbits. Minimal microbicidal concentration analysis showed prominent efficacy of PXL150 against P. aeruginosa in vitro, which was further enhanced in formulating the peptide in HPC gel. Application of 1.25, 2.5, 5, 10 and 20mg/g PXL150 in HPC gel twice daily for four consecutive days significantly reduced bacterial counts in the burn wounds compared with non-treated or placebo-treated controls. Continuous bioluminescence measurements of the bacteria revealed a pronounced anti-infective effect already at the first day post infection by PXL150 in concentrations of ≥2.5mg/g. In the non-clinical safety studies, PXL150 showed a favourable safety profile following repeated administration systemically and locally in rats and rabbits, respectively. In conclusion, these data support that PXL150 has the potential to be an effective and safe drug candidate for the treatment of infected burn wounds. The findings encourage the progression of PXL150 as a novel topical treatment of microbial infections.

Restoration of digital function after flexor tendon injuries remains a clinical challenge. Complications such as adhesion formation and tendon rupture can lead to limited hand function. The aim of this study was to compare the effects of the lactoferrin-derived peptide, PXL01, formulated in sodium hyaluronate (SH), with SH alone on joint mobility as an indirect measure of postsurgical adhesion prevention and healing strength of the tendon and to elucidate the most optimal concentration of PXL01.Using a rabbit flexor tendon repair model, in which the deep flexor tendon was fully transected and repaired, PXL01 in SH or SH alone was administered between the repaired tendon and the tendon sheath before closure of the surgical wound. Three concentrations of PXL01 in SH (5, 20, or 40 mg/mL) were compared to determine the lowest effective concentration. The repaired tendons were evaluated 7 weeks after surgery by measuring the proximal interphalangeal joint mobility by full range of flexion assessment and the tendon repair strength.Treatment with PXL01 formulated in SH resulted in improved mobility of the proximal interphalangeal joint with an average of 10°, corresponding to improvement of approximately 25% to 60% of the flexion of nonoperated toes at the different measuring points compared with SH alone. The difference was statistically significant in 5 out of 6 measuring points (0.5, 1, 2, 3, and 4 N; P.05). The dose-response study indicated that the lowest effective concentration of PXL01 was 20 mg/mL. There was no difference in healing strength of the tendon between the groups as assessed by load-to-failure breaking strength.PXL01 in SH significantly improved the mobility compared with the carrier SH alone, without any negative effect on healing strength, and PXL01 at 20 mg/mL was the lowest effective concentration.The result provides a valuable basis for a clinical trial to assess efficacy and safety of PXL01 in clinical hand surgery.

Background FOXC2 has lately been implicated in diabetes and obesity as well as mitochondrial function and biogenesis and also as a regulator of mtTFA/Tfam. In this study, the expression of FOXC2 and selected genes involved in mitochondrial function and biogenesis in healthy subjects and in a matched cohort with type 2 diabetes patients before and after treatment with rosiglitazone was determined. Quantitative real time PCR was used to analyze both RNA and DNA from biopsies from subcutaneous adipose tissue. Methods Blood samples and subcutaneous abdominal fat biopsies were collected from 12 T2D patients, of which 11 concluded the study, pre-treatment and 90 days after initiation of rosiglitazone treatment, and from 19 healthy control subjects on the first and only visit from healthy subjects. Clinical parameters were measured on the blood samples. RNA and DNA were prepared from the fat biopsies and gene expression was measured with real time PCR. Results The expression level of genes in the mitochondrial respiratory complexes I - IV were significantly downregulated in the diabetic patients and restored in response to rosiglitazone treatment. Rosiglitazone treatment also increased the relative number of mitochondria in diabetic patients compared with controls. Furthermore, the transcription factors FOXC2 and mtTFA/Tfam displayed a response pattern identical to the mitochondrial genes. Conclusions FOXC2, mtTFA/Tfam and subunits of the respiratory complexes I - IV show equivalent regulation in gene expression levels in response to TZD treatment. This, together with the knowledge that FOXC2 has a regulatory function of mtTFA/Tfam and mitochondrial biogenesis, suggests that FOXC2 has a possible functional role in the TZD activated mitochondrial response.