Resorbable membrane design: In vitro characterization of silver doped-hydroxyapatite-reinforced XG/PEI semi-IPN composite.

In this study, the production and characterization of silver-doped hydroxyapatite (AgHA) reinforced Xanthan gum (XG) and Polyethyleneimine (PEI) reinforced semi-interpenetrating polymer network (IPN) biocomposite, known to be used as bone cover material for therapeutic purposes in bone tissue, were performed. XG/PEI IPN films containing 2AgHA nanoparticles were produced by simultaneous condensation and ionic gelation. Characteristics of 2AgHA-XG/PEI nanocomposite film were evaluated by structural, morphological (SEM, XRD, FT-IR, TGA, TM, and Raman) and biological activity analysis (degradation, MTT, genotoxicity, and antimicrobial activity) techniques. In the physicochemical characterization, it was determined that 2AgHA nanoparticles were homogeneously dispersed in the XG/PEI-IPN membrane at high concentration and the thermal and mechanical stability of the formed film were high. The nanocomposites showed high antibacterial activity against Acinetobacter Baumannii (A.Baumannii), Staphylococcus aureus (S.aureus), and Streptococcus mutans (S.mutans). L929 exhibited good biocompatibility for fibroblast cells and was determined to support the formation of MCC cells. It was shown that a resorbable 2AgHA-XG/PEI composite material was obtained with a high degradation rate and 64% loss of mass at the end of the 7th day. Physico-chemically developed biocompatible and biodegradable XG-2AgHA/PEI nanocomposite semi-IPN films possessed an important potential for the treatment of defects in bone tissue as an easily applicable bone cover. Besides, it was noted that 2AgHA-XG/PEI biocomposite could increase cell viability, especially in dental-bone treatments for coating, filling, and occlusion.

Expression Levels of Glutathione S-Transferase and Cytochrome P450 Isoenzymes in Nasal Polyp Tissue.

Nasal polyps are benign sinonasal masses composed of eosinophils and extracellular edema. Pathogenesis of the polyp formation is unclear but several studies strongly suggest a correlation with infection, inflammation and allergy conditions. Our aim is to investigate the potential link between allergy and nasal polyp in tissue level. Nasal polyp group included 60 patients whose diagnosis was confirmed with biopsy and the control group included 38 healthy patients. Tissue sample of the control group was taken from inferior turbinate mucosa under local anesthesia and nasal polyp tissue was collected from functional endoscopic sinus surgery. The glutathione S-transferase (GST) and cytochrome P450 (CYP) isoenzyme expressions of the tissue samples were investigated under light microscopy and graded by a senior pathologist. GSTP1 protein expression was significantly higher in tissue samples from nasal polyp group compared to that of control group (p < 0.05). However, CYP1A1, GSTM1 and GSTA1 isoenzymes were not different between the two groups (p > 0.05). We have found that GSTP1 isoenzyme was elevated in nasal polyp tissue compared to the control. The increase in protein expression of GSTP1 might have occured as a tissue response to the increased oxidative stress thus suggesting a role of GSTP1 in polyp formation.

Synthesis and characterization of silver nanoparticles using curcumin: cytotoxic, apoptotic, and necrotic effects on various cell lines.

Nanostructures have distinctive chemical and physical features owing to their surface area and nanoscale size. In this study, silver nanoparticles were synthesized using curcumin, a medicinally valuable natural product. The structure of curcumin-mediated silver nanoparticles (c-AgNPs) was identified by extensive spectroscopic techniques. The maximum absorption was observed at 430 nm in UV-Vis spectrum. The crystal structure of c-AgNPs was identified by XRD. The morphology of the structure was determined by SEM image. The particle size was found as 51.13 nm. The functional groups of curcumin and c-AgNPs were established by FTIR spectroscopy. Cytotoxic activity of c-AgNPs was carried out using A549, DLD-1, and L929 with MTT assay. c-AgNPs revealed excellent activity on DLD-1 cell lines and A549 cell lines at 1.0 mg/mL concentration with the lethal effect of 80%. However, nanoparticles did not show the considerable effect on L929. Moreover, they induced apoptosis. Consequently, c-AgNPs are a promising material for anticancer drugs candidate.

Fabrication of mechanically advanced polydopamine decorated hydroxyapatite/polyvinyl alcohol bio-composite for biomedical applications: In-vitro physicochemical and biological evaluation.

In this study, polydopamine (PDA) coated hydroxyapatite (HA) reinforced polyvinyl alcohol (PVA) films were produced to be used in biomedical applications such as bone tissue regeneration. pDA is coated not only to prevent the agglomeration of HA when encountering interstitial fluids but also to strongly bind the PVA for the interaction between materials so that the mechanical performance becomes more stabilized. pDA was coated on the hydroxyapatite surface using a radical polymerization technique, and the reinforced PVA were produced with pDA-coated HA (pDA-HA/PVA) nanoparticles. Fundamental characteristic properties of pDA-HA/PVA nanocomposite films were examined by morphological/chemical (SEM-EDS), microstructural (XRD, Ft-IR, and Raman), thermodynamic (TGA and TM), mechanical performance (Vickers microhardness) and biological activity analysis (MTT, genotoxicity and antimicrobial efficacy investigations). Physicochemical analysis showed that all the samples studied exhibited homogeneous mineral distributions through the main structures. According to TGA, TMA and hardness tests, the new composite structure possessed higher mechanical properties than neat PVA. Further, pDA-HA/PVA nanocomposites exhibited high antibacterial capacities against Acinetobacter Baumannii (A.Baumannii), Staphylococcus aureus (S. aureus), and Streptococcus mutans (S.mutans). Moreover, the new nanocomposites were noted to present good biocompatibility for fibroblast (L929) cells and to support remarkably MCS cells. All in all, this comprehensive work shows that the thermo-mechanically improved pDA-HA/PVA films will increase the application fields of PVA in biomedical fields especially tooth-bone treatments for coating, filling, or occlusion purposes.

Glutathione S-transferase expression in benign and malignant eyelid tumors.

Eyelid tumors commonly originate from the skin and its appendages. Environmental toxins and oxidants affect eyelid carcinogenesis. Glutathione S-transferases (GST) are antioxidants that participate in pathogenesis. We investigated GST levels in malignant and benign eyelid tumors in otherwise healthy individuals. We used 57 malignant eyelid biopsies, benign eyelid biopsies, and tissue removed during blepharoplasty and entropion operations culled from pathology archives. Specimens were divided into three groups: malignant lesions, benign lesions and controls consisting of eyelid tissue removed during routine blepharoplasty and entropion surgery. Specimens were immunostained for seven GST (GST-A, GST-P, GST-Z, GST-S, GST-K, GST-O, GST-T) and the intensity of staining was quantified. In the malignant group, GST-O and GST-P staining was less intense than for the control group. In the benign group, the GST-P level was less than for the control group. We found no significant difference between the intensity of staining in malignant and benign groups. Our findings suggest that GST-O and GST-P enzymes may play significant roles in eyelid carcinogenesis.

Evolution of dynamics of physico-chemical and mechanical properties of hydroxyapatite with fluorine addition and degradation stability of new matrices.

This multidisciplinary study examined sensitively the change in the dynamics of main mechanical performance, stability of crystal structure, crystallinity quality, strength, corrosion resistance, biocompatibility, resistance to structural degradation/separations and mechanical durability features of hydroxyapatite (HAp) biomedical materials based on the fluorine addition and degradation process to guide future medical and dental treatment studies. In the study, the fluorine ions were used to be the dental coating, filling and supporting material for biologically or synthetically produced bone minerals. The general characteristic properties were investigated by means of standard spectroscopic, structural and mechanical analysis methods including RAMAN, SEM-EDS, TEM, Vickers micro-indentation hardness and density measurements. A time dependent release test was performed to evaluate possible fluorine ion release after the degradation process. It was found that the fundamental characteristic properties of HAp biomedical materials are noted to improve with the increase in the fluoride level up to 2% due much more stabilization of HAp crystal system. The combination of RAMAN spectra and powder XRD analyzes indicates that 2% addition level affects positively the formation velocity of characteristic HAP phase. Besides, fluorine doped HAp materials all exhibited the main characteristic peaks after degradation process. This is attributed to the fact that the fluorine ions enabled the hydroxyapatite to enhance the structural quality and stability towards the corrosion environment. However, in case of excess dopant level of 3% the degradation rates were obtained to increase due to higher contribution rate and especially electrostatic interactions. As for the surface morphology examinations, 2% fluorine added HAp with the highest density of 3.0879 g/cm3 was determined to present the superior crystallinity quality (smallest grain size, best smooth surface, honeycomb pattern, regular shaped particles and densest particle distributions through the specimen surface). Conversely, the excess fluorine triggered to increase seriously degree of micro/macro porosity in the surface morphology and microscopic structural problems in the crystal system. Thus, the HAp doped with 3% was the most affected material from the degradation process. Additionally, the fluorine ion values read after the release process were quite far from the value that could cause toxic effects. Lastly, the optimum fluorine addition provides the positive effects on the highest durability, stiffness and mechanical fracture strength properties as a consequence of differentiation in the surface residual compressive stress regions (lattice strain fields), amplification sites and active operable slip systems in the matrix. Hence, the crack propagations prefer to proceed in the transcrystalline regions rather than the intergranular parts. Similarly, it was found that Vickers micro-indentation hardness tests showed that the microhardness parameters increased after the degradation process. All in all, the fluorine addition level of 2% was noted to be good choice to improve the fundamental characteristic properties of hydroxyapatite biomedical materials for heavy-duty musculoskeletal, orthopedic implant, biological and therapeutic applications in medicine and dentistry application fields.

Expressions of glutathione S-transferase alpha, mu, pi, and theta in the skin samples of patients with acne rosacea.

BACKGROUND: Data point to the importance of oxidative stress in rosacea. Glutathione S-transferases (GSTs) have substantial roles in a wide variety of oxidative stress-related conditions. AIM: To evaluate the immunohistochemical staining characteristics of GST alpha (GSTA), mu (GSTM), pi (GSTP), and theta (GSTT) in patients with rosacea. PATIENTS/METHODS: The study included 23 women and 7 men with rosacea (mean ± SD age 49 ± 11 year) and 15 healthy control subjects (10 women, 5 men; mean ± SD age 47.86 ± 10.88 year). For each patient, the average disease duration, disease subtype, ocular involvement, and severity score were recorded. A 3-mm punch biopsy was taken from the facial skin of each patient and control. Expression of GST isoenzymes was analyzed immunohistochemically. RESULTS: Expressions of GSTM1, GSTP1, and GSTT1 were significantly elevated in patients with rosacea compared to those in the control group (P = .0001, P = .0002, P < .0001, respectively). In the rosacea group, GSTT1 expression was significantly stronger than GSTP1 and GSTA1 expressions (P = .019, P < .0001, respectively). There were no significant associations between expressions of GST isoenzymes and gender, age, average duration of illness, disease subtype, ocular involvement, or severity score in the patient group (all P > .05). CONCLUSIONS: In rosacea, the significant increase of GSTT1, GSTP1, and GSTM1 expressions might result from activation of GST as an outcome of extreme free radical generation from triggered neutrophils or ultraviolet vulnerability. These findings support the relevance of oxidant stress in the pathogenesis of rosacea.

An investigation of human beta-defensins and cathelicidin expression in patients with pterygium.

PURPOSE: To investigate human beta-defensins (HBDs) and cathelicidin LL-37 (LL-37) expressions in patients with pterygium. METHODS: In this retrospective consecutive case series, 26 pterygium specimens and 15 normal conjunctival specimens of 15 control subjects were in vestigated. Expressions of HBD-1, HBD-2, HBD-3, and LL-37 were assessed using immuno histochemical staining. A brown color in the cytoplasm and/or nuclei of epithelial cells indicated positive staining for HBDs and LL-37. For each antibody, the intensity of the reaction (negative [-], weak [1+], moderate [2+], or strong [3+]) was determined to describe the immunoreactions. RESULTS: The median age was 52 years in both groups. There were no significant differences in age and sex between the groups (p=0.583, p=0.355, respectively). Of the 26 pterygium specimens, 15 (57.7%) (14 weak, 1 moderate staining) showed HBD-2 expression, which was not observed in any of the control specimens. One (3.8%) pterygium and one (6.7%) control specimen demonstrated weak staining for HBD-3. HBD-2 expression was significantly higher in the pterygium specimens than in the controls (p=0.002). None of the tissue specimens had positive staining for HBD-1 or LL-37 in either group (both; p=1.00). CONCLUSIONS: HBD-2 expression was higher in pterygium specimens than in the controls. HBD-2 expression that might be stimulated by inflammatory cytokines may be related to inflammation and fibrovascular proliferation and may play a role in pterygium pathogenesis.

Investigation of Glutathione S-Transferase Isoenzyme Protein Expression in Patients With Pterygium.

PURPOSE: We investigated glutathione S-transferase (GST) enzymes in terms of their potential effects on the pathogenesis of pterygium. METHODS: Twenty-six pterygium specimens and 15 normal conjunctival specimens of 15 control subjects were investigated. Expressions of GST (alpha, mu, pi, and theta) enzymes were assessed by immunohistochemical staining. A brown color in the cytoplasm and/or nuclei of epithelial cells was evaluated as positive staining for GST enzymes. For each antibody, the intensity of the reaction [negative (-), weak (1+), moderate (2+), or strong (3+)] was determined to describe the immunoreactions. RESULTS: The median age was 52 years in the both groups. There was no significant difference between the groups in terms of age, sex, and intraocular pressure measurements (P > 0.05 for all). Of the 26 pterygium specimens, 15 (57.7%) (8 weak, 4 moderate, and 3 strong staining) were identified with GST pi-1 (GSTP1) expression and 20 (76.9%) (12 weak, 7 moderate, and 1 strong staining) with GST theta-1 (GSTT1) expression. Of the 15 control specimens, 4 (26.7%) (4 weak staining) were identified with the GSTP1 expression, and 1 (6.7%) with GSTT1 expression. GSTP1 and GSTT1 expressions were significantly higher in the pterygium specimens than in the controls (P = 0.043, P < 0.001; respectively). None of tissue specimens had positive staining for GST mu-1 or GST alpha-1 in both groups (both; P = 1.00). CONCLUSIONS: The significant increase of GSTP1 and GSTT1 expressions in pterygium may be because of the increased activation of GST in response to excessive free radical formation from ultraviolet exposure to maintain antioxidant capacity in pterygium.

An investigation of human beta-defensins and cathelicidin expression in patients with pterygium / Uma investigação da expressão de beta-defensinas humanas e de catelidicina em pacientes com pterígio

ABSTRACT Purpose: To investigate human beta-defensins (HBDs) and cathelicidin LL-37 (LL-37) expressions in patients with pterygium. Methods: In this retrospective consecutive case series, 26 pterygium specimens and 15 normal conjunctival specimens of 15 control subjects were in vestigated. Expressions of HBD-1, HBD-2, HBD-3, and LL-37 were assessed using immuno histochemical staining. A brown color in the cytoplasm and/or nuclei of epithelial cells indicated positive staining for HBDs and LL-37. For each antibody, the intensity of the reaction (negative [-], weak [1+], moderate [2+], or strong [3+]) was determined to describe the immunoreactions. Results: The median age was 52 years in both groups. There were no significant differences in age and sex between the groups (p=0.583, p=0.355, respectively). Of the 26 pterygium specimens, 15 (57.7%) (14 weak, 1 moderate staining) showed HBD-2 expression, which was not observed in any of the control specimens. One (3.8%) pterygium and one (6.7%) control specimen demonstrated weak staining for HBD-3. HBD-2 expression was significantly higher in the pterygium specimens than in the controls (p=0.002). None of the tissue specimens had positive staining for HBD-1 or LL-37 in either group (both; p=1.00). Conclusions: HBD-2 expression was higher in pterygium specimens than in the controls. HBD-2 expression that might be stimulated by inflammatory cytokines may be related to inflammation and fibrovascular proliferation and may play a role in pterygium pathogenesis.

RESUMO Objetivo: Investigar as expressões beta defensinas humanas (HBD) e catelicidina em pacientes com pterígio. Métodos: Nesta série de casos retrospectivos consecutivos, 26 espécimes de pterígio e 15 espécimes conjuntivais normais de 15 indivíduos controle foram investigados. As expressões de HBD-1, HBD-2, HBD-3 e catelicidina (LL-37) foram avaliadas por coloração imuno-histoquímica. Uma cor castanha no citoplasma ou nos núcleos de células epiteliais foi definida como coloração positiva para HBDs e LL-37. Para cada anticorpo foi determinada a intensidade da reação (negativo [-], fraco [1+], moderado [2+] ou forte [3+]) para descrever as imunoreações. Resultados: A idade média foi de 52 anos em ambos os grupos. Não houve diferença significativa entre os grupos em termos de idade e sexo (p=0,583, p=0,355, respectivamente). Das 26 amostras de pterígio, 15 (57,7%) (14 fracas e 1 moderada) demonstraram a expressão de HBD-2 enquanto não foi encontrada em nenhum dos espécimes de controlo. Um dos pterígios (3,8%) e um dos espécimes de controlo (6,7%) demonstraram fraca coloração para HBD-3. A expressão de HBD-2 foi significati vamente maior nos espécimes de pterígio do que nos controles (p=0,002). Nenhum dos espécimes de tecido apresentou coloração positiva para HBD-1 ou LL-37 em ambos os grupos (ambos p=1,00). Conclusão: Encontramos aumento da expressão de HBD-2 em espécimes de pte rígio em relação aos controles. A expressão de HBD-2 que pode ser estimulada por citocinas inflamatórias pode estar relacionada com inflamação e proliferação fibrovascular e pode desempenhar um papel na patogênese do pterígio.