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Inorganic perovskite CaMnO 3 ${{}_{3}}$ was proposed as a substitution for the TiO 2 ${{}_{2}}$ anatase in electron transport layers of solar cells containing the hybrid perovskite CH 3 ${{}_{3}}$ NH 3 ${{}_{3}}$ PbI 3 ${{}_{3}}$ based on increased mobility of electrons and better optical matching. Due to a suitable band gap concerning the absorption of sunlight, we investigate the potential of CaMnO 3 ${{}_{3}}$ and similar manganite perovskites, where Ca is replaced by either Sr, Ba or La, as an absorber layer in inorganic perovskite solar cells. In this study, we have used optical measurements on the synthesized AMnO 3 ${{}_{3}}$ (A=Ca, Sr, Ba, La) samples to aid density functional theory calculations (DFT) in order to accurately simulate the electronic and optical properties of AMnO 3 ${{}_{3}}$ compounds and gauge their potential for the role of absorber layer. Both experimental measurements and theoretical calculations show suitable band gap of 1.1-1.5â eV, depending on the compound, and absorption coefficients of the order of 10 5 ${{10}^{5}}$ cm - 1 ${{}^{-1}}$ in the visible part of the spectrum.
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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.
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Agrimonia , Animales , Modelos Animales de Enfermedad , Fibroblastos , Queratinocitos , Extractos Vegetales/farmacología , Ratas , Agua , Cicatrización de HeridasRESUMEN
Surfactant liquid-membrane type sensors are usually made of a PVC, ionophore and a plasticizer. Plasticizers soften the PVC. Due to their lipophilicity, they influence the ion exchange across the membrane, ionophore solubility, membrane resistance and, consequently, the analytical signal. We used the DMI-TPB as an ionophore, six different plasticizers [2-nitrophenyl-octyl-ether (P1), bis(2-ethylhexyl) phthalate (P2), bis(2-ethylhexyl) sebacate (P3), 2-nitrophenyl phenyl ether (P4), dibutyl phthalate (P5) and dibutyl sebacate (P6)] and a PVC to produce ionic surfactant sensors. Sensor formulation with P1 showed the best potentiometric response to four usually used cationic surfactant, with the lowest LOD, 7 × 10-7 M; and potentiometric titration curves with well-defined and sharp inflexion points. The sensor with P6 showed the lowest analytical performances. Surfactant sensor with P1 was selected for quantification of cationic surfactant in model solutions and commercial samples of disinfectants and antiseptics. It showed high accuracy and precision in all determinations, with recovery from 98.2 to 99.6, and good agreement with the results obtained with surfactant sensor used as a referent one, and a standard two-phase titration method. RDS values were lower than 0.5% for all determinations.
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Antiinfecciosos Locales , Desinfectantes , Concentración de Iones de Hidrógeno , Plastificantes , Cloruro de Polivinilo , Potenciometría , TensoactivosRESUMEN
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.
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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 broadscale engagement of members of the family of galactosidebinding lectins (galectins) in pathophysiological processes, such as cancer or tissue repair/regeneration, the present study investigated the potential of galectins1 (Gal1) and 3 (Gal3) in wound healing. Human dermal fibroblasts, which are key cells involved in skin wound healing, responded to galectin exposure (Gal1 at 300 or Gal3 at 600 ng/ml) with selective changes in gene expression among a panel of 84 woundhealingrelated genes, as well as remodeling of the extracellular matrix. In the case of Gal3, positive expression of Ki67 and cell number increased when using a decellularized matrix produced by Gal3treated fibroblasts as substrate for culture of interfollicular keratinocytes. In vivo wounds were topically treated with 20 ng/ml Gal1 or 3, and collagen score was found to be elevated in excisional wound repair in rats treated with Gal3. The tensile strength measured in incisions was significantly increased from 79.5±17.5 g/mm2 in controls to 103.1±21.4 g/mm2 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 TGFß1.
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Proteínas Sanguíneas/biosíntesis , Colágeno/biosíntesis , Dermis/metabolismo , Fibroblastos/metabolismo , Galectinas/biosíntesis , Regulación de la Expresión Génica , Resistencia a la Tracción , Heridas y Lesiones/metabolismo , Dermis/patología , Fibroblastos/patología , Humanos , Heridas y Lesiones/patologíaRESUMEN
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.
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Aesculus/química , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , Extractos Vegetales/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Cromatografía Líquida de Alta Presión , Estructura Molecular , Extractos Vegetales/química , Ratas , Regeneración , Resistencia a la TracciónRESUMEN
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.
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Células Endoteliales/citología , Genisteína/administración & dosificación , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Superóxido Dismutasa/metabolismo , Colgajos Quirúrgicos/fisiología , Animales , Supervivencia Celular , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Genisteína/farmacología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Modelos Animales , Ratas , Factores de Tiempo , Regulación hacia ArribaRESUMEN
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/cm2 infrared laser (SMD = 1.44, 95% CI 0.67-2.21) and 139-281 mW/cm2 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/cm2 infrared laser (SMD = 1.18, 95% CI 0.41-1.94) and 25-90 mW/cm2 red laser (SMD = 1.6, 95% CI 0.27-2.93). Whereas 1-15 mW/cm2 red laser had a moderately positive effect on sutured wounds, 2-4 mW/cm2 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.
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Terapia por Luz de Baja Intensidad/métodos , Herida Quirúrgica/terapia , Suturas , Heridas y Lesiones/radioterapia , Animales , Diabetes Mellitus/patología , Modelos Animales de Enfermedad , Resistencia a la Tracción , Cicatrización de HeridasRESUMEN
Estrogen deprivation is considered responsible for many age-related processes, including poor wound healing. Guided by previous observations that estradiol accelerates reepithelialization through estrogen receptor (ER)ß, in the present study, we examined whether selective ER agonists [4,4',4''-(4-propyl [1H] pyrazole-1,3,5-triyl)trisphenol (PPT), ERα agonist; 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN), ERß agonist] affect the expression of basic proliferation and differentiation markers (Ki67, keratin10, 14 and 19, galectin1 and Sox2) 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 ERα and ß, and thus are well-suited for studying the effects of ER agonists on epidermal regeneration. The activation of ERα produced a protein expression pattern similar to that observed in the control culture, with a moderate expression of Ki67 being observed. However, the activation of ERß led to an increase in cell proliferation and keratin19 expression, as well as a decrease in galectin1 expression. Fittingly, in rat wounds treated with the ERß 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 -ß has a direct impact on wound healing.
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Receptor alfa de Estrógeno/agonistas , Receptor beta de Estrógeno/agonistas , Queratinocitos/efectos de los fármacos , Nitrilos/farmacología , Fenoles/farmacología , Pirazoles/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Femenino , Humanos , Queratinocitos/citología , Queratinocitos/metabolismo , Queratinocitos/patología , Ratas Sprague-Dawley , Piel/efectos de los fármacos , Piel/metabolismo , Piel/patologíaRESUMEN
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.
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Agrimonia/química , Antioxidantes/química , Cynara/química , Fenoles/química , Extractos Vegetales/química , Animales , Antioxidantes/farmacología , Catalasa/metabolismo , Línea Celular/efectos de los fármacos , Línea Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Daño del ADN/efectos de los fármacos , Humanos , Estrés Oxidativo/efectos de los fármacos , Fenoles/farmacología , Extractos Vegetales/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
OBJECTIVES: Although the exact underlying mechanisms are still unknown, Plantago lanceolataâ 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.
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Miofibroblastos/metabolismo , Extractos Vegetales/farmacología , Plantago , Cicatrización de Heridas/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Resistencia a la TracciónRESUMEN
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.
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Galectinas/fisiología , Neoplasias/fisiopatología , Cicatrización de Heridas/fisiología , Animales , Transformación Celular Neoplásica/patología , Progresión de la Enfermedad , Matriz Extracelular/patología , Matriz Extracelular/fisiología , Humanos , Neoplasias/patologíaRESUMEN
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.
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Diabetes Mellitus Experimental/complicaciones , Terapia por Luz de Baja Intensidad , Piel/lesiones , Cicatrización de Heridas/efectos de la radiación , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Piel/efectos de la radiación , EstreptozocinaRESUMEN
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.
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Estradiol/análogos & derivados , Colgajos Quirúrgicos , Supervivencia Tisular/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Estradiol/farmacología , Terapia de Reemplazo de Estrógeno , Femenino , Necrosis , Ovariectomía , Ratas , Ratas Sprague-Dawley , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/patología , Cicatrización de Heridas/efectos de los fármacosRESUMEN
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.
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Fitoterapia , Extractos Vegetales/uso terapéutico , Piel/lesiones , Cicatrización de Heridas , HumanosRESUMEN
Galectins are a family of carbohydrate-binding proteins that modulate inflammation and immunity. This functional versatility prompted us to perform a histochemical study of their occurrence during wound healing using rat skin as an in vivo model. Wound healing is a dynamic process that exhibits three basic phases: inflammation, proliferation, and maturation. In this study antibodies against keratins-10 and -14, wide-spectrum cytokeratin, vimentin, and fibronectin, and non-cross-reactive antibodies to galectins-1, -2, and -3 were applied to frozen sections of skin specimens two days (inflammatory phase), seven days (proliferation phase), and twenty-one days (maturation phase) after wounding. The presence of binding sites for galectins-1, -2, -3, and -7 as a measure for assessing changes in reactivity was determined using labeled proteins as probes. Our study detected a series of alterations in galectin parameters during the different phases of wound healing. Presence of galectin-1, for example, increased during the early phase of healing, whereas galectin-3 rapidly decreased in newly formed granulation tissue. In addition, nuclear reactivity of epidermal cells for galectin-2 occurred seven days post-trauma. The dynamic regulation of galectins during re-epithelialization intimates a role of these proteins in skin wound healing, most notably for galectin-1 increasing during the early phases and galectin-3 then slightly increasing during later phases of healing. Such changes may identify a potential target for the development of novel drugs to aid in wound repair and patients' care.
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OBJECTIVE: The aim of our study was to compare the effects of different power densities of LLLT at 635 and 670 nm achieving a daily dose of 5 J/cm(2) on wound tensile strength (TS) in rats. BACKGROUND DATA: Optimal parameters of low-level laser therapy (LLLT) are still unknown. MATERIALS AND METHODS: Under general anesthesia, one full-thickness skin incision was performed on the back of each rat (n = 40) and immediately closed using an intradermal running suture. Rats were separated into five groups depending on treatment parameters: (1) sham irradiated control group (SIC); (2) 635 nm laser-treated group at 4 mW/cm(2) (L-635/4); (3) 635 nm laser-treated group at 15 mW/cm(2) (L-635/15); (4) 670 nm laser-treated group at 4 mW/cm(2) (L-670/4); and (5) 670 nm laser-treated group at 15 mW/cm(2) (L-670/15). The total daily dose was 5 J/cm(2). Seven days after surgery each wound was removed for wound TS measurement. RESULTS: The lowest wound TS results were measured in the SIC rats (10.5 +/- 2.8 g/mm(2)). Higher wound TS results were measured in group L-670/15 (11.5 +/- 2.5 g/mm(2)) and group L-635/4 (11.7 +/- 4.3 g/mm(2)) rats, while significantly higher results were found in group L-670/4 (15.8 +/- 4.4 g/mm(2)) and group L-635/15 (15.9 +/- 4.8 g/mm(2)). The differences were significant between certain groups (p < 0.01: SIC vs. L-635/15, SIC vs. L-670/4; p < 0.05: L-635/4 vs. L-635/15, L-635/4 vs. L-670/4, L-635/15 vs. L-670/15, L-670/4 vs. L-670/15). CONCLUSION: Both red lasers significantly increased wound TS at selected parameters. Whereas the 635 nm laser significantly improved wound healing by using the higher power density, the 670 nm laser improved healing using a lower power density.