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A practical and representative sampling method for microbiological examination of the slaughter process is useful for identifying abattoir-specific risk factors within the pig slaughter line. The aim of this study was to examine the suitability of an agar contact method (ACM), where the agar was homogenized before the microbiological processing, in comparison with the wet-dry double swabbing method (WDSM) for quantitative determination of total viable counts (TVC) on pig skin surfaces. In our experimental trial, pig skin pieces were artificially contaminated at 2 levels (3 log and 7 log cfu/ml) with a suspension of bacteria species commonly found on pig skin and cultivated in vitro. Within our field trial, pig carcasses were investigated at pre-chilling in an abattoir under standard processing conditions. For both sampling methods, TVC was determined, and statistical equivalence tests were calculated. Linear regression models showed the similarity of the sampling methods, with coefficient of determination (R2) > 90% and slope parameters of nearly 1 for both trials separately. Statistically significant equivalence between the 2 sampling methods was proven in both trials (with p < 0.0001 within an equivalence range of ± 0.5 log cfu/ml, respectively). The field trial revealed TVC on carcass surfaces sometimes at or below the lower detection limit for the ACM, while TVC from all carcasses were able to be determined by WDSM. Overall, low contamination levels were less reliably detectable by ACM than by WDSM. The ACM can be seen as an additional and suitable sampling procedure for pig skin and can contribute to the identification of abattoir specific risk factors for investigations of the hygienic status at process stages along the pig slaughter line. [ABSTRACT FROM AUTHOR]

Exposure to high acute doses of ionizing radiation (IR) can induce cutaneous radiation syndrome. Weeks after such radiation insults, keratinocyte nuclei of the epidermis exhibit persisting genomic lesions that present as focal accumulations of DNA double-strand break (DSB) damage marker proteins. Knowledge about the nanostructure of these genomic lesions is scarce. Here, we compared the chromatin nano-architecture with respect to DNA damage response (DDR) factors in persistent genomic DNA damage regions and healthy chromatin in epidermis sections of two minipigs 28 days after lumbar irradiation with ~50 Gy γ-rays, using single-molecule localization microscopy (SMLM) combined with geometric and topological mathematical analyses. SMLM analysis of fluorochrome-stained paraffin sections revealed, within keratinocyte nuclei with perisitent DNA damage, the nano-arrangements of pATM, 53BP1 and Mre11 DDR proteins in γ-H2AX-positive focal chromatin areas (termed macro-foci). It was found that persistent macro-foci contained on average ~70% of 53BP1, ~23% of MRE11 and ~25% of pATM single molecule signals of a nucleus. MRE11 and pATM fluorescent tags were organized in focal nanoclusters peaking at about 40 nm diameter, while 53BP1 tags formed nanoclusters that made up super-foci of about 300 nm in size. Relative to undamaged nuclear chromatin, the enrichment of DDR protein signal tags in γ-H2AX macro-foci was on average 8.7-fold (±3) for 53BP1, 3.4-fold (±1.3) for MRE11 and 3.6-fold (±1.8) for pATM. The persistent macro-foci of minipig epidermis displayed a ~2-fold enrichment of DDR proteins, relative to DSB foci of lymphoblastoid control cells 30 min after 0.5 Gy X-ray exposure. A lasting accumulation of damage signaling and sensing molecules such as pATM and 53BP1, as well as the DSB end-processing protein MRE11 in the persistent macro-foci suggests the presence of diverse DNA damages which pose an insurmountable problem for DSB repair. [ABSTRACT FROM AUTHOR]

To provide meat safety and consumer protection, appropriate hygiene control measures at an abattoir are required. This study aimed to evaluate the influence of visual fecal contamination level (VFCL) and lairage time (LT) on pig skin (PS) and external (ECS) and internal (ICS) carcass surfaces. The presence of Enterobacteriaceae, Escherichia coli (E. coli) and Salmonella in PS, ECS, and ICS were evaluated. A total of 300 paired samples were collected from 100 pigs. Results underlined the importance of the skin (Enterobacteriaceae: 3.27 ± 0.68 log CFU/cm2; E. coli: 3.15 ± 0.63 log CFU/cm2; Salmonella: 21% of samples) as a direct or indirect source of carcass contamination. Although VFCL revealed no significant effect (p > 0.05), the increase of LT had a significant impact (p < 0.001) on Enterobacteriaceae and E. coli levels across all analysed surfaces, and Salmonella presence on ICS (p < 0.01), demanding attention to LT. Also, the ICS showed a higher level of these bacteria compared to ECS. These results highlight the need of food business operators to consider ICS as an alternative area to sample for Salmonella, as a criterion for process hygiene based on EC Regulation No. 2073/2005, and as a potential contamination source to be integrated in the hazard analysis critical control point (HACCP) plans. [ABSTRACT FROM AUTHOR]

To provide meat safety and consumer protection, appropriate hygiene control measures at an abattoir are required. This study aimed to evaluate the influence of visual fecal contamination level (VFCL) and lairage time (LT) on pig skin (PS) and external (ECS) and internal (ICS) carcass surfaces. The presence of Enterobacteriaceae, Escherichia coli (E. coli) and Salmonella in PS, ECS, and ICS were evaluated. A total of 300 paired samples were collected from 100 pigs. Results underlined the importance of the skin (Enterobacteriaceae: 3.27 ± 0.68 log CFU/cm2; E. coli: 3.15 ± 0.63 log CFU/cm2; Salmonella: 21% of samples) as a direct or indirect source of carcass contamination. Although VFCL revealed no significant effect (p > 0.05), the increase of LT had a significant impact (p < 0.001) on Enterobacteriaceae and E. coli levels across all analysed surfaces, and Salmonella presence on ICS (p < 0.01), demanding attention to LT. Also, the ICS showed a higher level of these bacteria compared to ECS. These results highlight the need of food business operators to consider ICS as an alternative area to sample for Salmonella, as a criterion for process hygiene based on EC Regulation No. 2073/2005, and as a potential contamination source to be integrated in the hazard analysis critical control point (HACCP) plans.

Chicken sausage is one of the very popular meat products. In order to change the nutritional composition of chicken sausage and increase the content of dietary fiber, we add bran, but it affects the textural properties of chicken sausage. Pork rind is rich in collagen and is a natural and safe food gel. Pork rind content affects the cooking loss, color, TPA, moisture distribution and sensory evaluation results of cooked sausage products. In this study, six different pigskin content treatment experiments were set up: 0 %, 5 %, 10 %, 15 %, 20 %, and 25 %. This research shows that adding pork rind can reduce cooking loss during the sausage heating process. As more pork rind was added, the L* and b* values of minced meat and chicken sausage gradually increased, while the a* value gradually decreased. The chewiness of the sausages in the test group was significantly reduced (p<0.05), except for T1, while the elasticity, recovery, and cohesiveness did not change significantly (p>0.05), and the hardness value increased significantly (p<0.05). The hardness of the sausages increased significantly (except in T5). Compared with the control group, the relaxation times of hydrated water and immobilized water in the treatment group became shorter, while the relaxation times of free water shifted to a longer direction. Sensory evaluation revealed that the hardness score of the T5 group was significantly lower than that of the control group. Based on these results, the sausage quality of the T3 group (pork rind 15 %) was the highest. This study improves the gel properties of bran chicken sausage, provides scientific data support for the application of pork rind in chicken sausage, improving the application value of pork rind [ABSTRACT FROM AUTHOR]

Abstract The administration of medications on the skin through transcutaneous routes is a practice that has been used by mankind for millennia. Some studies have been reporting the use of terpenes and natural oils rich in terpenes as an enhancer of cutaneous penetration. Copaiba oil, due to its rich content of terpenes, presents itself as a great choice of penetration enhancer for drugs administered on the skin. In this study, we developed two cream formulations containing 5% of ibuprofen (IBU) and copaiba oil: IBCO5 and IBCO10 with 5% and 10% of copaiba oil respectively. Ex vivo cutaneous penetration/permeation studies of IBU were performed using pig ear skin as biological membrane in the Franz-type diffusion cells. The steady-state flux of IBU samples, IBCO5 (35.72 ± 6.35) and IBCO10 (29.78 ± 2.41) were significantly higher when compared with control without copaiba oil (10.32 ±1.52) and with a commercial product (14.44 ± 2.39). In the penetration analysis, the amount of IBU found in the samples IBCO5 and IBCO10 was markedly higher in the dermis than epidermis. Our results showed that copaiba oil possesses attracting properties in promoting skin penetration and permeation of IBU when added into cream formulations.

Purpose: In wound ballistics, skin has obvious blocking effect in the biological target penetration of projectiles. An analytical description of skin mechanical properties under compression can set the basis for the numerical simulation and the evaluation of blocking effect. Methods: In this study, an improved three-parameter solid visco-elastic model was proposed to describe the skin creep phenomenon. And then combined with Maxwell and Ogden model, a new nonlinear skin constitutive model, consisting of hyper-elastic unit, creep unit and relaxation unit in parallel, was established. Here, we examine the material properties of freshly harvested porcine skin in compression at strain rates from 0.01/s to 4000/s. Results: The model is verified by comparison with the experimental results by our test and that in the literature at different strain rates. Conclusions: It shows that calculated results of the constitutive model agree well with the experiment data at extremely low to high strain rates, which is useful for the description of the heterogeneous, nonlinear viscoelastic, relaxation and creep mechanical response of skin under compression. [ABSTRACT FROM AUTHOR]

We have previously reported the design of a portable 109 Cd x-ray fluorescence (XRF) system to measure iron levels in the skin of patients with either iron overload disease, such as thalassemia, or iron deficiency disease, such as anemia. In phantom studies, the system was found to have a detection limit of 1.35 μ g Fe per g of tissue for a dose of 1.1 mSv. However, the system must provide accurate as well as precise measurements of iron levels in the skin in order to be suitable for human studies. The accuracy of the system has been explored using several methods. First, the iron concentrations of ten pigskin samples were assessed using both the portable XRF system and ICP-MS, and the results were compared. Overall, it was found that XRF and ICP-MS reported average values for iron in skin that were comparable to within uncertainties. The mean difference between the two methodologies was not significant, 2.5 ± 4.6 μ g Fe per g. On this basis, the system could be considered accurate. However, ICP-MS measurements reported a wider range of values than XRF, with two individual samples having ICP-MS results that were significantly elevated (p < 0.05) compared to XRF. Synchrotron μ XRF maps of iron levels in pigskin were acquired on the BioXAS beam line of the Canadian Light Source. The μ XRF maps indicated two important features in the distribution of iron in pigskin. First, there were small areas of high iron concentration in the pigskin samples, that were predominantly located in the dermis and hypodermis at depths greater than 0.5 mm. Monte Carlo modelling using the EGS 5 code determined that if these iron 'hot spots' were located towards the back of the skin at depths greater than 0.5 mm, they would not be observed by XRF, but would be measured by ICP-MS. These results support a hypothesis that iron levels in the two samples that reported significantly elevated ICP-MS results compared to XRF may have had small blood vessels at the back of the skin. Second, the synchrotron μ XRF maps also showed a narrow (approximately 100μm thick) layer of elevated iron at the surface of the skin. Monte Carlo models determined that, as expected, the XRF system was most sensitive to these skin layers. However, the simulations found that the XRF system, when calibrated against homogenous water-based phantoms, was found to accurately measure average iron levels in the skin of normal pigs despite the greater sensitivity to the surface layer. The Monte Carlo results further indicated that with highly elevated skin surface iron levels, the XRF system would not provide a good estimate of average skin iron levels. The XRF estimate could, with correction factors, provide a good estimate of the iron levels in the surface layers of skin. There is limited data on iron distribution in skin, especially under conditions of disease. If iron levels are elevated at the skin surface by diseases including thalassemia and hemochromatosis, this XRF device may prove to be an accurate clinical tool. However, further data are required on skin iron distributions in healthy and iron overload disease before this system can be verified to provide accurate measurements., (Creative Commons Attribution license.)

Transdermal delivery of drugs represents a non-invasive alternative treatment used not only for skin diseases. As one of the possible penetration enhancing agents, various types of nanoparticles (NPs) could be used. Silver NPs (AgNPs) could be used for some medical purposes considering their antibacterial and antiinflammatory properties. We demonstrate a novel method of quantification of permeated AgNPs, detection of AgNPs dissolving while passing the skin, and examination of interactions between skin and systems with AgNPs. Several AgNPs (exhibiting defined mean diameters of 20, 40, 60, and 100 nm) were added individually to the pure solvents commonly used in pharmaceuticals, namely ethanol, methanol, dimethyl sulfoxide, and demineralized water. AgNP dispersions in different solvents were applied to untreated samples of the skin. Attenuated total reflection technique was used for monitoring the kinetic series of infrared spectra to elucidate the time-dependent changes in the uppermost layer of the skin. The depth profiling spectra series were measured using confocal Raman microspectrometer. All recorded vibrational spectra were evaluated by multivariate statistical methods. A strong influence of AgNP size on the structural changes of the skin surface was evident. The largest changes of the skin structure were caused by the 20-nm and 40-nm AgNPs. Permeation of used AgNPs was studied on vertical Franz diffusion cells with detection of permeated AgNPs by new method based on single-particle inductively coupled plasma mass spectrometry. [ABSTRACT FROM AUTHOR]

Absorption through the skin of topically applied chemicals is relevant for both formulation development and safety assessment, especially in the early stages of development. However, the supply of human skin is limited, and the traditional in vitro methods are of low throughput. As an alternative, an artificial membrane-based Skin Parallel Artificial Membrane Permeability Assay (Skin-PAMPA) has been developed to mimic the permeability through the stratum corneum. In this study, this assay was used to measure the permeability of a model compound, 4-phenylethyl-resorcinol (PER), dissolved in 13 different solvents that are commonly used in cosmetic formulation development. The study was performed at concentrations close to the saturated solution of PER in each solvent to investigate the maximum thermodynamic potential of the solvents. The permeability of PER in selected solvents was also measured on ex vivo pig skin for comparison. Pig ear skin is an accepted alternative model of human skin. The permeability coefficient, which is independent of the concentration of the applied solution, showed a good correlation (R2 = 0.844) between the Skin-PAMPA and the pig skin permeation data. Our results support the use of the Skin-PAMPA to screen the suitability of different solvents for non-polar compounds at an early stage of formulation development.

Identifying therapeutic oligonucleotides that are cross-reactive to experimental animal species can dramatically accelerate the process of preclinical development and clinical translation. Here, we identify fully chemically-modified small interfering RNAs (siRNAs) that are cross-reactive to Janus kinase 1 (JAK1) in humans and a large variety of other species. We validated the identified siRNAs in silencing JAK1 in cell lines and skin tissues of multiple species. JAK1 is one of the four members of the JAK family of tyrosine kinases that mediate the signaling transduction of many inflammatory cytokine pathways. Dysregulation of these pathways is often involved in the pathogenesis of various immune disorders, and modulation of JAK family enzymes is an effective strategy in the clinic. Thus, this work may open up unprecedented opportunities for evaluating the modulation of JAK1 in many animal models of human inflammatory skin diseases. Further chemical engineering of the optimized JAK1 siRNAs may expand the utility of these compounds for treating immune disorders in additional tissues., Competing Interests: A.K. is a founder of Atalanta Therapeutics and Comanche Biopharma; serves on the Scientific Advisory Board of Aldena Therapeutics, Prime Medicine, Alltrna, and Evox Therapeutics; and owns equities in RXi Pharmaceuticals and Advirna. J.E.H. owns equities in Rheos Medicines, and is a founder of Villaris Therapeutics, Aldena Therapeutics, NIRA Biosciences, Vimela Therapeutics, and Klirna Therapeutics. Q.T., H.H.F., K.Y.G., M.Z.U.I.A., K.R.M., J.E.H., A.K., and J.F.A. are listed as inventors of RNAi technology patents and patent applications. C.B., C.B.-P., and T.P. are executives of Aldena Therapeutics.

Transdermal drug delivery of lidocaine is a good choice for local anesthetic delivery. Microemulsions have shown great effectiveness for the transdermal transport of lidocaine. Oil-in-water nanoemulsions are particularly suitable for encapsulation of lipophilic molecules because of their ability to form stable and transparent delivery systems with good skin permeation. However, fabrication of nanoemulsions containing lidocaine to provide an extended local anesthetic effect is challenging. Hence, the aim of this study was to address this issue by employing alginate-based o/w nanocarriers using nanoemulsion template that is prepared by combined approaches of ultrasound and phase inversion temperature (PIT). In this study, the influence of system composition such as oil type, oil and surfactant concentration on the particle size, in vitro release and skin permeation of lidocaine nanoemulsions was investigated. Structural characterization of lidocaine nanoemulsions as a function of water dilution was done using DSC. Nanoemulsions with small droplet diameters (d < 150 nm) were obtained as demonstrated by dynamic light scattering (DLS) and cryo-TEM. These nanoemulsions were also able to release 90% of their content within 24-h through PDMS and pig skin and able to the drug release over a 48-h. This extended-release profile is highly favorable in transdermal drug delivery and shows the great potential of this nanoemulsion as delivery system.

[Display omitted] Wound healing is a natural physiological reaction to tissue injury. Hydrogels show attractive advantages in wound healing not only due to their biodegradability, biocompatibility and permeability but also because provide an excellent environment for cell migration and proliferation. The main objective of the present study was the design and characterization of a hydrogel loaded with human mesenchymal stromal cells (hMSCs) for use in would healing of superficial skin injures. Poloxamer 407® was used as biocompatible biomaterial to embed hMSCs. The developed hydrogel containing 20 % (w/w) of polymer resulted in the best formulation with respect to physical, mechanical, morphological and biological properties. Its high swelling capacity confirmed the hydrogel's capacity to absorb wounds' exudate. LIVE/DEAD® assay confirm that hMSCs remained viable for at least 48 h when loaded into the hydrogels. Adding increasing concentrations of hMSCs-loaded hydrogel to the epithelium did not affect keratinocytes' viability and healing capacity and all wound area was closed in less than one day. Our study opens opportunities to exploit poloxamer hydrogels as cell carriers for the treatment of skin superficial wound. [ABSTRACT FROM AUTHOR]

Background: The survival of microorganisms on textiles and specifically on healthcare professionals' (HCP) attire has been demonstrated in several studies. The ability of microorganisms to adhere and remain on textiles for up to hours or days raises questions as to their possible role in transmission from textile to skin via HCP to patients., Aim: To evaluate the presence, survival and transmission of different multidrug-resistant bacteria (MDRB) from HCP attire onto skin., Methods: Three MDRB [methicillin-resistant Staphylococcus aureus (MRSA); vancomycin-resistant Enterococcus faecium (VRE) ; carbapenem-resistant Klebsiella pneumoniae , CRKP)] were inoculated on textiles from scrubs (60% cotton-40% polyester) and white coat (100% cotton) at concentrations of 10 8 colony-forming units (CFU), 10 5 CFU, and 10 3 CFU per mL. The inoculation of swatches was divided in time intervals of 1 min, 5 min, 15 min, 30 min, 1 h, 2 h, 3 h, 4 h, 5 h, and 6 h. At the end of each period, textiles were imprinted onto pig skins and each skin square was inverted onto three different selective chromogenic media. Growth from the pig skin squares was recorded for the 3 MDRB at the three above concentrations, for the whole length of the 6-h experiment., Results: MRSA was recovered from pig skins at all concentrations for the whole duration of the 6-h study. VRE was recovered from the concentration of 10 8 CFU/mL for 6 h and from 10 5 CFU/mL for up to 3 h, while showing no growth at 10 3 CFU/mL . CRKP was recovered from 10 8 CFU/mL for 6 h, up to 30 min from 10 5 CFU/mL and for 1 min from the concentration of 10 3 CFU/mL., Conclusion: Evidence from the current study shows that MRSA can persist on textiles and transmit to skin for 6 h even at low concentrations. The fact that all MDRB can be sustained and transferred to skin even at lower concentrations, supports that textiles are implicated as vectors of bacterial spread., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

A simple and sensitive analytical method for the quantification of D,L-amino acids by ultra-performance liquid chromatography (UPLC) with fluorescence (FL) detection is described. The reaction of the R(-)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole [R(-)-DBD-PyNCS] with D,L-hydroxyproline (Hyp), glycine (Gly), D,L-aspartic acid (Asp), and D,L-proline (Pro) effectively proceeds at 55 °C for 20 min in the presence of 3% TEA to produce the corresponding fluorescent diastereomers (excitation at 460 nm, emission at 550 nm). The mixture was simultaneously separated within 20 min on an ACQUITY UPLCTM BEH C18 (1.7 μm, 100 mm × 2.1 mm i.d.) by gradient elutions using water-acetonitrile containing 0.2% formic acid as the mobile phase. Peak resolution was in the range of 1.62 (D,L-Asp), 2.99 (D,L-Pro), and 6.74 (D,L-Hyp). A good linearity was achieved from the calibration curves (r2 > 0.9984) in the range of 1.0~100 pmol; the limit of detection (S/N = 3) was 42.0-250 fmol, the inter-day and intra-day assay precisions were all less than 6.23%, and the mean recoveries (%) of the D,L-amino acids spiked in the collagen from pig and dried cod skins were 87.58-107.41%. The derivatives of the free D,L-amino acids in the collagen were successfully identified by the proposed procedure. To the best of our knowledge, for the first time, these three kinds of D-amino acids, which were D-Asp, D-Pro, and D-Hyp, were detected in the collagen samples. [ABSTRACT FROM AUTHOR]

In this research, the exponential stretched based hyperelastic strain energy was generalized to the hyper-viscoelastic model using the heredity integral of deformation history to take into account the strain rate effects on the mechanical behavior of materials. The heredity integral was approximated by the approach of Goh et al. to determine the model parameters and the same estimation was used for constitutive modeling. To present the ability of the proposed hyper-viscoelastic model, the stress-strain response of the thermoplastic elastomer gel tissue at different strain rates from 0.001 to 100/s was studied. In addition to better agreement between the current model and experimental data in comparison to the extended Mooney-Rivlin hyper-viscoelastic model, a stable material behavior was predicted for pure shear and balance biaxial deformation modes. To present the engineering application of current model, the Kolsky bars impact test of gel tissue was simulated and the effects of specimen size and inertia on the uniform deformation were investigated. As the mechanical response of polyurea was provided over wide strain rates of 0.0016–6500/s, the current model was applied to fit the experimental data. The results were shown more accuracy could be expected from the current research than the extended Ogden hyper-viscoelastic model. In the final verification example, the pig skin experimental data was used to determine parameters of the hyper-viscoelastic model. Subsequently, a specimen of pig skin at different strain rates was loaded to a fixed strain and the change of stress with time (stress relaxation) was obtained. The stress relaxation results were revealed the peak stress increases by applied strain rate until the saturated loading rate and the equilibrium stress with magnitude of 0.281 MPa could be reached. [ABSTRACT FROM AUTHOR]

The effects of the mixture of pig skin (PS) and coconut powder (CP) on the gelling and rheological properties of composite gel prepared with squid myofibrillar protein (MP) and lard were studied. The addition of PS and CP gel had significantly improved the water-holding capacity (WHC) and gelling properties of MP-Lard composite gel. Besides, composite gels with an adequate amount of PS and CP gel had a better texture and higher whiteness. The SDS-PAGE results showed that the presence of PS and CP gel did not affect the coagulated proteins in composite gels. The three-dimensional network structures of composite gels containing PS and CP gel were more compact and homogeneous. In general, the mixture of PS and CP could enhance the gel quality of MP-Lard composite gel and it could be used as a fat substitute in surimi products. [ABSTRACT FROM AUTHOR]

The functionality and structural properties of pig skin hydrolysates with different degrees of hydrolysis (DH, 10% and 20%) and microfluidisation (120 MPa), prepared by pepsin and Alcalase® have been investigated in this study. Extensive hydrolysis can significantly improve the absolute value of the zeta potential and surface hydrophobicity. The particle distribution of hydrolysates decreased with increasing DH. The numbers of free sulfhydryl (SH) and disulfide bonds (SS) were significantly increased with increasing DH ( p < 0.05). Hydrolysates with a lower DH showed a better emulsifying property than those with a higher DH. Microfluidisation led to the transformation of structural and interfacial properties of the hydrolysates and increased the value of the zeta potential, S 0 , and gel strength. Microfluidisation results in limited breakage of chemical bonds, the number of SS and SH bonds unchanged in the treatment. These results reflect the functionality and structural properties of collagen-rich pig skin hydrolysates. [ABSTRACT FROM AUTHOR]

Skin contamination is one of the most probable risks following major nuclear or radiological incidents. However, accidents involving skin contamination with radionuclides may occur in the nuclear industry, in research laboratories and in nuclear medicine departments. This work aims to measure the penetration of the radiological contaminant Americium ( 241 Am) in fresh and frozen skin and to evaluate the distribution of the contamination in the skin. Decontamination tests were performed using water, Fuller’s earth and diethylene triamine pentaacetic acid (DTPA), which is the recommended treatment in case of skin contamination with actinides such as plutonium or americium. To assess these parameters, we used the Franz cell diffusion system with full-thickness skin obtained from pigs’ ears, representative of human skin. Solutions of 241 Am were deposited on the skin samples. The radioactivity content in each compartment and skin layers was measured after 24 h by liquid scintillation counting and alpha spectrophotometry. The Am cutaneous penetration to the receiver compartment is almost negligible in fresh and frozen skin. Multiple washings with water and DTPA recovered about 90 % of the initial activity. The rest remains fixed mainly in the stratum corneum. Traces of activity were detected within the epidermis and dermis which is fixed and not accessible to the decontamination. [ABSTRACT FROM AUTHOR]

Skin can be damaged by the environment easily. Skin cream is an effective and rapid way to moisten the skin by changing the skin surface properties. Rat skin and pig skin are common animal models for studies and were used as skin samples in this study. The nano- and macroscale friction and durability of damaged skin were measured and compared with those of virgin (intact/undamaged) skin. The effect of skin cream on friction and durability of damaged and virgin skin samples is discussed. The effects of velocity, normal load, relative humidity and number of cycles were studied. The nanoscale studies were performed by using atomic force microscope (AFM), and macroscale studies were performed by using a pin-on-disk (POD) reciprocating tribometer. It was found that damaged skin has different mechanical properties, surface roughness, contact angle, friction and durability compared to that of virgin skin. But similar changes occur after skin cream treatment. Rat and pig skin show similar trends in friction and durability.

Latanoprost (LAT) has been shown to have a hypertrichotic effect, which makes it a promising candidate for alopecia treatments. For the first time, LAT has been encapsulated in nanotransfersomes in order to increase its efficacy. Ex vivo skin biodistribution was studied by confocal laser microscopy both in human scalp and pig skin. Results showed that nanotransfersomes increase the penetration of two different fluorochromes, with similar patterns in both species, compared with fluorochrome solutions containing no nanotransfersomes. Nanotransfersomes were stable under accelerated conditions (40 °C/75% RH) and long-term conditions (25 °C/60% RH) for up to 1 year, with no differences in vesicle size and polydispersity when LAT was loaded. Nanotransfersomes increased the LAT cell proliferation effect in HaCaT cell via MAPK signaling pathway. Collectively, our results demonstrate LAT-nanotransfersomes formulation could be a promising therapy for hair growth disorders.

Background: Burns are a major cause of death and disability worldwide. Today biological dressings have become an integral part of modern burn care. Using this method, in otherwise healthy young adults, the size of burn relative to the total body surface area (TBSA) correlating with a 50% mortality rate has increased from 30% to 80%. Due to a lack of experience and an interest in using biological dressings in Iran, as a developing country, the aim of this study was to compare patient outcome using the biological dressing vs. conventional treatment in patients with massive burns.Methods: In this clinical trial study, 118 burn patients (30 to 75% TBSA) were enrolled. The patients were divided in two groups. Those in the conventional treatment group had not accepted treatment with a biological dressing. The second group agreed to treatment with biological dressing, a pig skin xenograft known as Xenoderm. Significant differences were evaluated using the unpaired Student's t test, the Mann-Whitney U test and the χ2 test. Results: Mortality rates in the conventional treatment group (n=53) and biological dressing group (n=65) were 35% (19) and 10.8% (7), respectively (p=0.001). Excluding those patients who died, the mean hospital stay was 31.3 days in the conventional treatment group versus 18.2 days in the biological dressing group (p=0.0005), and number of dressings was 22.1 versus 9.9 (p=0.0005), respectively. Three patients in the conventional treatment group were transferred to a tertiary-care hospital after three weeks of treatment. The most commonly burned areas were the upper limb, lower limb and trunk.Conclusions: The results of this study indicate that biological dressings give a better outcome and decrease the hospital stay and the number of dressings. A randomized clinical trial is warranted.

In this work, diclofenac was encapsulated, as sodium salt, in glycerosomes containing 10, 20 or 30% of glycerol in the water phase with the aim to ameliorate its topical efficacy. Taking into account previous findings, glycerosome formulation was modified, in terms of economic suitability, using a cheap and commercially available mixture of hydrogenated soy phosphatidylcholine (P90H). P90H glycerosomes were spherical and multilamellar; photon correlation spectroscopy showed that obtained vesicles were ∼131 nm, slightly larger and more polydispersed than those made with dipalmitoylphosphatidylcholine (DPPC) but, surprisingly, they were able to ameliorate the local delivery of diclofenac, which was improved with respect to previous findings, in particular using glycerosomes containing high amount of glycerol (20 and 30%). Finally, this drug delivery system showed a high in vitro biocompatibility toward human keratinocytes. [ABSTRACT FROM AUTHOR]

Allantoin is traditionally employed in the treatment of skin ulcers and hypertrophic scars. In the present work, to improve its local deposition in the skin and deeper tissues, allantoin was incorporated in conventional liposomes and in new argan oil enriched liposomes. In both cases, obtained vesicles were unilamellar, as confirmed by cryo-TEM observation, but the addition of argan oil allowed a slight increase of the mean diameter (∼130 nm versus ∼85 nm). The formulations, especially those containing argan oil, favoured the allantoin accumulation in the skin, in particular in the dermis (∼8.7 μg/cm 2 ), and its permeation through the skin (∼33 μg/cm 2 ). The performances of vesicles as skin delivery systems were compared with those obtained by water dispersion of allantoin and the commercial gel, Sameplast ® . Moreover, in this work, for the first time, the elastic and viscous moduli of the skin were measured, underlining the different hydrating/moisturizing effects of the formulations. The application of ARG liposomes seems to provide a softening and relaxing effect on the skin, thus facilitating the drug accumulation and passage into and trough it. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the destruction of clinically-relevant bacteria within biofilms via the sustained release of the antibiotic tetracycline from zein-based electrospun polymeric fibrous matrices and to demonstrate the compatibility of such wound dressing matrices with human skin cells. Methods: Zein/PCL triple layered fibrous dressings with entrapped tetracycline were electrospun. The successful entrapment of tetracycline in these dressings was validated. The successful release of bioactive tetracycline, the destruction of preformed biofilms, and the viability of fibroblast (FEK4) cells were investigated. Results: The sustained release of tetracycline from these matrices led to the efficient destruction of preformed biofilms from Staphylococcus aureus MRSA252 in vitro, and of MRSA252 and ATCC 25923 bacteria in an ex vivo pig skin model using 1 × 1 cm square matrices containing tetracycline (30 μg). Human FEK4 cells grew normally in the presence of these matrices. Conclusions: The ability of the zein-based matrices to destroy bacteria within increasingly complex in vitro biofilm models was clearly established. An ex vivo pig skin assay showed that these matrices, with entrapped tetracycline, efficiently kill bacteria and this, combined with their compatibility with a human skin cell line suggest these matrices are well suited for applications in wound healing and infection control. [ABSTRACT FROM AUTHOR]