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The article deals with the process of surface remelting of steel 41CrAlMo7 by electric arc (TIG) in the presence of powders with a defined chemical composition. Commercially available powders Pulnierpulver based on calcium cyanamide (CaCN2) (source of nitrogen) and Durborit G based on boron carbide B4C (source of boron) were remelted. The effect of remelting on the change of microstructure in the remelted area was examined to achieve an increase in hardness and resistance to abrasive wear. The measurements of the hardness of HV 1 were carried out, as well as determination of resistance to abrasive wear on the abrasive cloth with Al2O3 particles. The microstructures of remelted layers were observed by LOM and details by SEM. By remelting the examined steel, a significant increase in hardness and resistance to abrasive wear was achieved to a depth of up to 1.5 mm from the surface. An almost four times increase in hardness and an almost two times increase in wear resistance was found when remelting the Pulnierpulver powder, or more than three times increase in hardness and more than 1.5 times increase in resistance to abrasive wear when remelting the Durborit G powder compared to steel without remelting. The presented procedure of TIG surface remelting of powders containing a certain element represents a cheap, accessible, and fast way of creating surface layers with increased hardness and wear resistance. The method is applicable for increasing the wear resistance of functional parts of machines for agriculture, earthmoving, etc.

The paper explores the interrelationship of technological capabilities and firm performance of Croatian export firms. The primary aim of the study is to provide answer to research question: Are the most successful export firms in the Republic of Croatia prosperous due to the possession of technological capabilities? Firms with high level of technological capabilities enter the foreign markets more easily and more successfully and increase the share and dispersion of their international sales faster in comparison to their competitors. Proposition regarding relationships between technological capabilities and the firm’s performance has been examined by multiple regression analysis, with the following variables: investment in technology, investment in research and development, the frequency of introducing new products and technological solutions, and return of sales and increase of total revenue. The results of research have shown that technological capabilities have a positive impact on the return of sales and an increase of total income in Croatian export firms.

Background/aim: We have previously shown that the water extract of Agrimonia eupatoria L. (AE) is a valuable source of polyphenols with excellent antioxidant properties and has clinical potential for the prevention and/or adjuvant therapy of cardiovascular complications associated with diabetes. Inspired by our previously published data, in the present study we examined whether AE improves skin wound healing in a series of in vitro and in vivo experiments., Materials and Methods: In detail, we investigated the ability of the AE extract to induce fibroblast to myofibroblast conversion, extracellular matrix (ECM) deposition, and keratinocyte proliferation/differentiation, in vitro. In parallel, in an animal model, we measured wound tensile strength (TS) and assessed the progression of open wounds using basic histology and immunofluorescence., Results: The AE extract induced the myofibroblast-like phenotype and enhanced ECM deposition, both in vitro and in vivo. Furthermore, the wound TS of skin incisions and the contraction rates of open excisions were significantly increased in the AE-treated group., Conclusion: The present data show that AE water extract significantly improves the healing of open and sutured skin wounds. Therefore, our data warrant further testing in animal models that are physiologically and evolutionarily closer to humans., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

The present paper analyzes the damage of surfaces at spots of frictional contact, namely, the friction nodes on a camshaft and the connecting rod pins of a crankshaft. The resulting wear of the monitored friction nodes reduces the technical life of the machines, which can lead to the decommissioning of the machine. Wear was assessed by measuring roughness and microhardness and by observing the microstructures of the materials. The results of the experiments show that the rotating parts displayed visible wear on the cams, as well as on the connecting rod pins. The experiments revealed that wear was caused by the heating of the material to a high temperature during the operation of the machine and that there was a gradual cooling and tempering of the material, which led to a reduction in the microhardness of the monitored object. Lower microhardness values can be a cause of greater wear of the monitored objects. When comparing the microhardness of the used and the new camshaft, the hardened layer of the new camshaft from secondary production has a significantly smaller thickness compared to worn cams, which leads to the finding of a different material quality compared to the original parts from primary production. This fact indicates that the wear of a new camshaft as a spare part can contribute to the shortening of the technical life of friction nodes.

Introduction: Endometriosis is defined as the presence of endometrial tissue, endometrial glands or endometrial stroma outside the uterine cavity causing chronic inflammatory response. The prevalence of abdominal wall endometriosis is less than 1%. Cesarean scar endometriosis is the most common type of abdominal wall endometriosis. Chronic lower abdominal pain amplified during menstruation and palpable mass in the area of scar are the main symptoms. Generally, surgical resection with negative resection margins offers the best chance for definitive treatment of abdominal wall endometriosis., Case Report: The authors present two female patients in fertile age with chronic pain in the area of Cesarean scar. The preoperatively assumed endometriosis was histologically confirmed after complete surgical excision., Conclusion: Abdominal wall endometriosis is rare. However, it is a possible cause of constant lower abdominal pain, impacting quality of life of the patient.

Understanding the molecular and cellular processes in skin wound healing can pave the way for devising innovative concepts by turning the identified natural effectors into therapeutic tools. Based on the concept of broad‑scale engagement of members of the family of galactoside‑binding lectins (galectins) in pathophysiological processes, such as cancer or tissue repair/regeneration, the present study investigated the potential of galectins‑1 (Gal‑1) and ‑3 (Gal‑3) in wound healing. Human dermal fibroblasts, which are key cells involved in skin wound healing, responded to galectin exposure (Gal‑1 at 300 or Gal‑3 at 600 ng/ml) with selective changes in gene expression among a panel of 84 wound‑healing‑related genes, as well as remodeling of the extracellular matrix. In the case of Gal‑3, positive expression of Ki67 and cell number increased when using a decellularized matrix produced by Gal‑3‑treated fibroblasts as substrate for culture of interfollicular keratinocytes. In vivo wounds were topically treated with 20 ng/ml Gal‑1 or ‑3, and collagen score was found to be elevated in excisional wound repair in rats treated with Gal‑3. The tensile strength measured in incisions was significantly increased from 79.5±17.5 g/mm 2 in controls to 103.1±21.4 g/mm 2 after 21 days of healing. These data warrant further testing mixtures of galectins and other types of compounds, for example a combination of galectins and TGF‑β1.

The ability of horse chestnut extract (HCE) to induce contraction force in fibroblasts, a process with remarkable significance in skin repair, motivated us to evaluate its wound healing potential in a series of experiments. In the in vitro study of the ability of human dermal fibroblasts to form myofibroblast-like cells was evaluated at the protein level (Western blot and immunofluorescence). The in vivo study was conducted on male Sprague-Dawley rats with inflicted wounds (one open circular and one sutured incision) on their backs. Rats were topically treated with two tested HCE concentrations (0.1% and 1%) or sterile water. The control group remained untreated. The incisions were processed for wound tensile strength (TS) measurement whereas the open wounds were subjected to histological examination. On the in vitro level the HCE extract induced fibronectin-rich extracellular matrix formation, but did not induced α-smooth muscle actin (SMA) expression in dermal fibroblasts. The animal study revealed that HCE increased wound TS and improved collagen organization. In conclusion, the direct comparison of both basic wound models demonstrated that the healing was significantly increased following HCE, thus this extract may be found useful to improve healing of acute wounds. Nevertheless, the use of an experimental rat model warrants a direct extrapolation to the human clinical situation.

Although low-level laser therapy (LLLT) was discovered already in the 1960s of the twentieth century, it took almost 40 years to be widely used in clinical dermatology/surgery. It has been demonstrated that LLLT is able to increase collagen production/wound stiffness and/or improve wound contraction. In this review, we investigated whether open and sutured wounds should be treated with different LLLT parameters. A PubMed search was performed to identify controlled studies with LLLT applied to wounded animals (sutured incisions-tensile strength measurement and open excisions-area measurement). Final score random effects meta-analyses were conducted. Nineteen studies were included. The overall result of the tensile strength analysis (eight studies) was significantly in favor of LLLT (SMD = 1.06, 95% CI 0.66-1.46), and better results were seen with 30-79 mW/cm 2 infrared laser (SMD = 1.44, 95% CI 0.67-2.21) and 139-281 mW/cm 2 red laser (SMD = 1.52, 95% CI 0.54-2.49). The overall result of the wound contraction analysis (11 studies) was significantly in favor of LLLT (SMD = 0.99, 95% CI 0.38-1.59), and the best results were seen with 53-300 mW/cm 2 infrared laser (SMD = 1.18, 95% CI 0.41-1.94) and 25-90 mW/cm 2 red laser (SMD = 1.6, 95% CI 0.27-2.93). Whereas 1-15 mW/cm 2 red laser had a moderately positive effect on sutured wounds, 2-4 mW/cm 2 red laser did not accelerate healing of open wounds. LLLT appears effective in the treatment of sutured and open wounds. Statistical heterogeneity indicates that the tensile strength development of sutured wounds is more dependent on laser power density compared to the contraction rate of open wounds.

Selective estrogen receptor modulators (SERMs) have been developed to achieve beneficial effects of estrogens while minimizing their side effects. In this context, we decided to evaluate the protective effect of genistein, a natural SERM, on skin flap viability in rats and in a series of in vitro experiments on endothelial cells (migration, proliferation, antioxidant properties, and gene expression profiling following genistein treatment). Our results showed that administration of genistein increased skin flap viability, but importantly, the difference is only significant when treatment is started 3 days prior the flap surgery. Based on our in vitro experiments, it may be hypothesized that the underlying mechanism may rather by mediated by increasing SOD activity and Bcl-2 expression. The gene expression profiling further revealed 9 up-regulated genes (angiogenesis/inflammation promoting: CTGF, CXCL5, IL-6, ITGB3, MMP-14, and VEGF-A; angiogenesis inhibiting: COL18A1, TIMP-2, and TIMP-3). In conclusion, we observed a protective effect of genistein on skin flap viability which could be potentially applied in plastic surgery to women undergoing a reconstructive and/or plastic intervention. Nevertheless, further research is needed to explain the exact underlying mechanism and to find the optimal treatment protocol., Competing Interests: The authors declare no conflict of interest.

Estrogen deprivation is considered responsible for many age-related processes, including poor wound healing. Guided by previous observations that estradiol accelerates re‑epithelialization through estrogen receptor (ER)‑β, in the present study, we examined whether selective ER agonists [4,4',4''-(4-propyl [1H] pyrazole-1,3,5-triyl)‑trisphenol (PPT), ER‑α agonist; 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN), ER‑β agonist] affect the expression of basic proliferation and differentiation markers (Ki‑67, keratin‑10, ‑14 and ‑19, galectin‑1 and Sox‑2) of keratinocytes using HaCaT cells. In parallel, ovariectomized rats were treated daily with an ER modulator, and wound tissue was removed 21 days after wounding and routinely processed for basic histological analysis. Our results revealed that the HaCaT keratinocytes expressed both ER‑α and ‑β, and thus are well-suited for studying the effects of ER agonists on epidermal regeneration. The activation of ER‑α produced a protein expression pattern similar to that observed in the control culture, with a moderate expression of Ki‑67 being observed. However, the activation of ER‑β led to an increase in cell proliferation and keratin‑19 expression, as well as a decrease in galectin‑1 expression. Fittingly, in rat wounds treated with the ER‑β agonist (DPN), epidermal regeneration was accelerated. In the present study, we provide information on the mechanisms through which estrogens affect the expression patterns of selected markers, thus modulating keratinocyte proliferation and differentiation; in addition, we demonstrate that the pharmacological activation of ER-α and -β has a direct impact on wound healing.

Reactive oxygen species (ROS) are highly considered in the ethiopathogenesis of different pathological conditions because they may cause significant damage to cells and tissues. In this paper, we focused on potential antioxidant properties of two medical plants such as the Agrimonia eupatoria L. and Cynara cardunculus L. Both plants have previously been studied for their pharmacological activities, especially as hepatoprotective and hypoglycemic activities. It has been suggested, that their effects are related to the antioxidant properties of polyphenols, which are dominant compounds of the plants' extracts. In the present study HPLC-MS analysis of water infusion was performed allowing the identification of several phenolic constituents. Furthermore, antioxidant effects of the two extracts were compared showing higher effects for agrimony extract compared to artichoke. Thus, agrimony was selected for the in vivo study using the skin flap viability model. In conclusion, our results provide evidence that the A. eupatoria extract may be a valuable source of polyphenols to be studied for the future development of supplements useful in the prevention of diseases linked to oxidative stress.

Objectives: Although the exact underlying mechanisms are still unknown, Plantago lanceolata L. (PL) water extracts are frequently used to stimulate wound healing and to drain abscesses. Therefore, in this experimental study the effect of PL water extract on skin wound healing was studied in Sprague-Dawley rats., Methods: Two excisional and one incisional skin wounds were performed on the back of each rat. Wounds were treated for three consecutive days with two different concentrations of the aqueous extract of PL. Rats were sacrificed 7, 14, and 21 days after surgery. Samples of wounds were processed for macroscopic (excisions - wound contraction measurement), biomechanical (incisions - wound tensile strength (TS) measurement) and histological examination (excisions)., Key Findings: It was shown that open wounds treated with PL extract contained myofibroblasts and demonstrated significantly higher contraction rates. Furthermore, significantly increased wound TSs were recorded in treated rats as a consequence of increased organization of extracellular matrix proteins, such as the collagen type 1., Conclusions: We demonstrated that PL aqueous extract improves skin wound healing in rats. However, further research need to be performed to find optimal therapeutic concentration, and exact underlying mechanism prior obtained results may be introduced into the clinical practice., (© 2014 Royal Pharmaceutical Society.)

Objective: The aim of present study was to evaluate whether low-level laser therapy (LLLT) can reverse the impaired wound healing process in diabetic rats., Background Data: Impaired wound healing in diabetic patients represents a major health problem. Recent studies have indicated that LLLT may improve wound healing in diabetic rats, but the optimal treatment parameters are still unknown., Materials and Methods: Male Sprague-Dawley rats (n=21) were randomly divided into three groups: a healthy control group, a diabetic sham-treated group, and a diabetic LLLT-treated group. Diabetes mellitus was then induced by streptozotocin administration to the two diabetic groups. One 4 cm long full thickness skin incision and one full thickness circular excision (diameter=4 mm) were performed on the back of each rat. An infrared 810 nm laser with an output of 30 mW, a power density of 30 mW/cm(2), and a spot size of 1 cm(2) was used to irradiate each wound for 30 sec (daily dose of 0.9 J/cm(2)/wound/day)., Results: In diabetic rats, the histology of LLLT-treated excisions revealed a similar healing response to that in nondiabetic controls, with significantly more mature granulation tissue than in the sham-treated diabetic control group. LLLT reduced the loss of tensile strength, and increased the incision wound stiffness significantly compared with sham-irradiated rats, but this did not achieve the same level as in the nondiabetic controls., Conclusions: Our study demonstrates that infrared LLLT can improve wound healing in diabetic rats. Nevertheless, further research needs to be performed to evaluate the exact underlying mechanism and to further optimize LLLT parameters for clinical use.

Endometriosis is defined as the presence of functional endometrial tissue outside the uterine cavity. The most common clinical symptoms of endometriosis are infertility and chronic pelvic pain. Endometriosis affects 8-10% of women of reproductive age and the condition is highly associated with infertility. Ectopic endometrial tissue is usually found in the small pelvis and the peritoneum, but endometrial tissue deposits have also been reported in other anatomical locations in the human body. We describe the case of a young patient with persistent abdominal pain and bleeding via the rectum during menstrual periods, hospitalised at the Second Department of Surgery, Pavol Jozef Šafárik University, Faculty of Medicine and Louis Pasteur University Hospital Košice.

Galectins are representatives of endogenous lectins - molecules specifically recognizing distinct sugar motifs. They play an important role in the processes of cell proliferation, differentiation, migration and extracellular matrix formation. Furthermore, galectins are able to transfer cellular signals and to participate in intercellular interaction. It has been proven that galectins play an important role in the formation of tumor and/or wound healing microenvironment. This review contains an overview of experimental and clinical studies dealing with biological roles of galectins in tissue repair and in its parallel - the tumor growth.

Background: It has been shown that estrogens have a protective effect with regard to tissue ischemia. Therefore, in this macroscopic and histological investigation, the effect of estradiol benzoate on skin flap viability was studied in sham-operated and ovariectomized Sprague-Dawley rats., Methods: Three months prior to flap surgery a group of rats underwent ovariectomy, while the remaining animals underwent a sham operation. Subsequently, all rats had a 2 × 8-cm skin flap created on the dorsum. Rats were randomly divided into estradiol- or saline-treated groups. Treatment started either on the day of flap excision or 3 days prior to the surgery., Results: Our results showed that administration of estradiol benzoate prior to and after flap surgery significantly decreases skin flap necrosis in both sham-operated and ovariectomized rats, with the highest survival rate in animals where treatment started 3 days prior to flap surgery., Conclusion: In conclusion, the observed protective effect of estradiol on skin flap viability could potentially be applied to plastic and reconstructive surgery in postmenopausal women. Nevertheless, further research is needed to explain the exact underlying mechanism and to find the optimal treatment protocol for human clinical practice.

Delayed wound healing presents a significant burden for the patient and healthcare system. One of many possibilities how to improve the process of wound healing and to prevent development of unwanted complications is the use of herbal substances which are still commonly used in folk medicine. This review gives an overview of experimental and clinical studies related to phytotherapeutic approaches of skin wound healing which have during the 21st century been indexed by the largest biomedical database NCBI - PubMed.