Synthesis and characterization of Hypsizygus ulmarius extract mediated silver nanoparticles (AgNPs) and test their potentiality on antimicrobial and anticancer effects.

The prime aim of this research is to discover new, eco-friendly approaches to reducing agents for manufacturing silver nanoparticles (AgNPs) from fresh fruiting bodies of the edible mushroom Hypsizygus ulmarius (Hu). The confirmation of Hu-mediated AgNPs has been characterized by UV visible spectroscopy, XRD, FTIR, SEM with EDX, HRTEM, AFM, PSA, Zeta poetical and GCMS analysis. The absorption peak of Hu-AgNPs at 430 nm has been confirmed by UV-visible spectroscopy analysis. The findings of the particle size study show that AgNPs have a size distribution with an average of 20 nm. The Zeta potential of NPs reveals a significant build-up of negative charges on their surface. The additional hydrate layers that occurred at the surface of AgNPs are shown in the HR-TEM morphology images. The antibacterial activity results showed that Hu-AgNPs were highly effective against both bacterial pathogens, with gram-positive (+) and gram-negative (-) pathogens having a moderate inhibition effect on K. pneumoniae (5.3 ± 0.3 mm), E. coli (5.3 ± 0.1), and S. aureus (5.2 ± 0.3 mm). Hu-AgNPs (IC50 of 50.78 µg/mL) were found to have dose-dependent cytotoxic action against human lung cancer cell lines (A549). Inhibited cell viability by up to 64.31% after 24 h of treatment. To the best of our knowledge, this is the hand information on the myco-synthesis of AgNPs from the H. ulmarius mushroom extract and the results suggest that it can an excellent source for developing a multipurpose and eco-friendly nano product in future.

Combining Mesenchymal Stem Cells Derived from Wharton's Jelly and Amniotic Biomaterial Scaffolds for Cell Delivery.

Therapies based on mesenchymal stem cells have incredible potential for tissue regeneration. Tracking cells and keeping them at the injury site are creating challenges. The cells can be sown into a biocompatible scaffold as a possible remedy. Tissue engineering construction is a difficult, multistep process that requires many variables to be optimized, including the stem cell source, molecular components, scaffold architecture, and a suitable in vivo animal model. In order to locate a suitable regenerative scaffold for delivering stromal cells to regions with greater healing potential, we assessed whether human Wharton's Jelly-derived mesenchymal stem cells (WJMSCs) responded on biological membranes. WJMSCs were isolated, characterized, and seeded onto an amniotic membrane-based scaffold. Results obtained in vitro revealed that the seeded scaffolds had a significant impact on a number of critical variables, including seeding effectiveness, cellular dispersion, adhesion, survival, and metabolic activity. The research sheds light on a fresh facet of material behavior and paves the way for the creation of scaffold materials that support tissue regeneration and repair. Furthermore, the methods used herein can be utilized to test other scaffold materials to increase their healing potential with WJMSCs.

Transient downregulation of NR4A1 leads to impaired osteoblast differentiation through the TGF-ß pathway, and Elesclomol (STA-4783) rescues this phenotype.

Bone formation is regulated by numerous factors, such as transcription factors, cytokines, and extracellular matrix molecules. Human hormone nuclear receptors (hHNR) are a family of ligand-regulated transcription factors that are activated by steroid hormones, such as estrogen and progesterone, and various lipid-soluble signals, including retinoic acid, oxysterols, and thyroid hormone. We found that an hHNR called NR4A1 was the most highly expressed after human MSC differentiation into osteoblasts by whole-genome microarray. NR4A1 knockout decreased the osteoblastic differentiation of hMSCs in terms of ALPL expression and key marker gene expression. Whole-genome microarray analysis further confirmed the decrease in key pathways when we knocked down NR4A1. Further studies with small molecule activators identified a novel molecule called Elesclomol (STA-4783), which could activate and enhance osteoblast differentiation. Elesclomol activation of hMSCs also induced the gene expression of NR4A1 and rescued the phenotype of NR4A1 KD. In addition, Elesclomol activated the TGF-ß pathway by regulating key marker genes. In conclusion, we first identified the role of NR4A1 in osteoblast differentiation and that Elesclomol is a positive regulator of NR4A1 through activation of the TGF-ß signalling pathway.

Au integrated 2D ZnO heterostructures as robust visible light photocatalysts.

Integration of semiconducting nanostructures with noble metal nanoparticles are turning highly desirable for cost efficient energy and environmental related applications. From this viewpoint, we report on a facile aqueous synthesis of polymer capped gold (Au) nanoparticles on free standing 2D layered structures of zinc oxide (ZnO) to result with ZnO/Au nanocomposites. Concentration of Au nanoparticles were observed to promote the preferential growth of ZnO along the (002) wurtzite plane. The ZnO/Au structures and their morphological dissemination was noted to be of few. This flake like structure was also noted to be greatly influenced by the concentration of Au in the colloidal blend. Optical band edge transformations noted in the absorption spectra across the lower wavelength region and the shift in surface plasmon resonance (SPR) towards the red region of the visible spectrum signify the improved absorptivity of the heterostructures along the visible spectrum. These heterostructures exhibited remarkable visible light driven photocatalytic activity (99% efficiency) on par with pristine ZnO. The findings also attest this new class of composite structures to open up new openings in diversified solar energy conversion related functions.

Surface dissolution and transesterification of thermoset dimethacrylate polymer by dimethacrylate adhesive resin and organic catalyst-alcohol solution.

OBJECTIVES: To evaluate transesterification based dissolution of dimethacrylate and epoxy polymers, the former containing ester groups. Polymer substrates were treated with an adhesive resin (Stick™ Resin) and an organic catalyst-alcohol solution (ethylene glycol and triazabicyclodecene). The surface was chemically and nanomechanically analyzed with Fourier Transform-Infrared (FTIR) spectroscopy, surface profile peak (Rp) and nanohardness and modulus of elasticity. METHODS: A total of 100 specimens each of light-cured dimethacrylate polymer and heat-cured diepoxy polymer were prepared. 20 specimens were randomly selected and used as control group (0s). The remaining specimens were randomly divided into 40 each for treatment with an Stick™ resin and ethylene glycol+triazabicyclodecene. Within each group the 40 specimens were randomly subdivided into 20 each for treatment at 5min and 24h, with 10 specimens for FTIR and nanohardness and modulus of elasticity, and the other 10 for SEM and surface Rp analyses. RESULTS: Dimethacrylate polymer showed a reduction in the nanohardness and modulus of elasticity, Rp values and SEM also showed significant topographical changes after being treated with either Stick™ resin or ethylene glycol+triazabicyclodecene, whereas epoxy resin substrate did not. FTIR analyses affirmed changes in the intensity of ester groups. SIGNIFICANCE: Ester group containing dimethacrylate polymer showed a reduction in NMP within 5min of exposure to the treatment agents with softening by solution ethylene glycol+triazabicyclodecene associated to the reduction of ester groups in the polymer structure by transesterification. Epoxy polymer without ester groups was not affected by surface softening with treatment agents. Adhesive resin caused surface swelling.

The effect of ethanol on surface of semi-interpenetrating polymer network (IPN) polymer matrix of glass-fibre reinforced composite.

AIM OF THE STUDY: The aim of this laboratory study was to evaluate the effect of ethanol treatment on the surface roughness (Sa), nano-mechanical properties (NMP) and surface characterization of dental fiber reinforced composite (FRC) with semi-interpenetrating polymer network (IPN). MATERIALS AND METHODS: A total of 240 FRC specimens with bisphenol A-glycidyl methacrylate - triethyleneglycol dimethacrylate - Poly (methylmetahcrylate) (bis-GMA-TEGDMA-PMMA) IPN matrix system were light cured for 40 s and divided into 2 groups (L and LH). The group LH was further post-cured by heat at 95 °C for 25 min. The specimens were exposed to 99.9%, 70% and 40% for 15, 30, 60 and 120 s respectively. The treated specimens were evaluated for Sa using non-contact profilometer. NMP were determined using nanoindentation technique and chemical characterization was assessed by Fourier Transform-Infrared (FTIR) spectroscopic analyses. Scanning electron microscopic (SEM) images were made to evaluate the surface topographical changes. RESULTS: Both the L and LH group showed changes in the Sa and NMP after being treated by different concentrations of ethanol and at different time interval. The highest Sa was observed with L-group (0.733 µm) treated with 99.9% ethanol for 120 s. Specimens in LH-group treated with 99.9% ethanol for 120 s (1.91 GPa) demonstrated increased nano-hardness, and group treated with 40% ethanol for 120 s demonstrated increased Young's modulus of elasticity (22.90 GPa). FTIR analyses revealed changes in the intensity and bandwidth in both the L and LH groups. CONCLUSION: The present study demonstrated that both light-cured and heat post-cured FRC were prone for ethanol induced alteration in the surface roughness (Sa), nano-mechanical properties (NMP) and chemical characterization. The interphase between the glass fibers and the organic matrix was affected by ethanol. The changes were considerably less in magnitude in the heat post-cured FRC specimens.

Effect of ethanol treatment on mechanical properties of heat-polymerized polymethyl methacrylate denture base polymer.

This laboratory study was assessing the nano-mechanical properties (NMP), surface roughness (Sa), and topographic changes caused by ethanol on the surface of heat-polymerized denture base polymers at different time past dough stage. Specimens of heat polymerizing acrylic resin (Interacryl Hot, Interdent, Celje, Slovenia) of size 10×10×3 mm were prepared, wet ground, and polished for uniform smoothness and treated with ethanol in concentrations of 40, 70, and 99.9% for 30, 60, and 120 s and statistical analysis was done. Some statistical significance for Sa were highest with 120 s exposure to 40% ethanol. NMP were the highest for specimens treated with 99.9% ethanol concentration for 120 s, on specimens prepared 30 min past the dough stage. This study suggested that heat-polymerized denture base polymers are prone for changes by ethanol which alters mechanical properties and surface topography. Dough time influenced the ethanol resistance.

Effect of smoking on the genetic makeup of toll-like receptors 2 and 6.

BACKGROUND: Cigarette smoking is a major risk factor for lung cancer, asthma, and oral cancer, and is central to the altered innate immune responsiveness to infection. Many hypotheses have provided evidence that cigarette smoking induces more genetic changes in genes involved in the development of many cigarette-related diseases. This alteration may be from single-nucleotide polymorphisms (SNPs) in innate immunity genes, especially the toll-like receptors (TLRs). OBJECTIVE: In this study, the genotype frequencies of TLR2 and TLR6 in smoking and nonsmoking population were examined. METHODS: Saliva samples were collected from 177 smokers and 126 nonsmokers. The SNPs used were rs3804100 (1350 T/C, Ser450Ser) and rs3804099 (597 T/C, Asn199Asn) for TLR2 and rs3796508 (979 G/A, Val327Met) and rs5743810 (745 T/C, Ser249Pro) for TLR6. RESULTS: Results showed that TLR2 rs3804100 has a significant effect in short-term smokers (OR =2.63; P=0.04), and this effect is not observed in long-term smokers (>5 years of smoking). Therefore, this early mutation may be repaired by the DNA repair system. For TLR2 rs3804099, the variation in genotype frequencies between the smokers and control patients was due to a late mutation, and its protective role appears only in long-term smokers (OR =0.40, P=0.018). In TLR6 rs5743810, the TT genotype is significantly higher in smokers than in nonsmokers (OR =6.90). The effect of this SNP is observed in long-term smokers, regardless of the smoking regime per day. CONCLUSION: TLR2 (rs3804100 and rs3804099) and TLR6 (rs5743810) can be used as a potential index in the diagnosis and prevention of more diseases caused by smoking.

Photoactivated disinfection (PAD) of dental root canal system - An ex-vivo study.

AIM: To investigate the efficacy of photo activated disinfection (PAD) in reducing colony-forming unit (CFU) counts of Enterococcus faecalis (E. faecalis) in infected dental root canals. The study compared the efficacy of PAD with conventional endodontic treatment (CET) and also a combination of CET along with PAD. MATERIAL AND METHODS: 53 maxillary incisors were taken for the study. Teeth were divided into 3 groups, CET (Group I) (n = 11), PAD (Group II) (n = 21), and a combination of CET and PAD (Group III) which consisted of (n = 21) samples, Group II and Group III were further divided into 2 subgroups, Group IIa, IIb and Group IIIa, IIIb. Strains of E. faecalis were inoculated in all the root canals. CET group samples were treated by chemo-mechanical preparation (CMP) alone, PAD samples were treated with laser alone at 2 different exposure time (4 min and 2 min). In the combination treatment, samples were treated initially by CET and then by PAD for a time period of 4 min and 2 min. Contents of the root canal were aspirated, diluted and plated in Tryptone Soya Broth (TSB) and plates were incubated for 24 h to observe the bacterial regrowth. RESULTS: Showed PAD used along with CMP reduced the bacterial load of E. faecalis by 99.5% at 4 min and 98.89% at 2 min. CONCLUSION: PAD may be an adjunctive procedure to kill residual bacteria in the dental root canal systems after standard endodontic root canal preparation.

Effect of solvent/disinfectant ethanol on the micro-surface structure and properties of multiphase denture base polymers.

AIM OF THE STUDY: The aim of this study was to evaluate the effect of solvent/disinfectant ethanol on the surface of denture base polymers. Changes in surface roughness, topography and some nanomechanical properties were assessed by SEM and nanoindentation plotted against different concentrations of ethanol on heat cured and autopolymerized polymetyl methacrylate based acrylic denture base polymers. MATERIALS AND METHODS: Test specimens (10×10×3mm(3)) of heat-curing (HC) and auto-polymerizing (AP) acrylic resin were prepared and polished to obtain uniform smoothness which were further grouped into 3 sub-groups HC1, HC2, HC3 and AP1, AP2, AP3 respectively 10 specimens (n) in each group. HC1 and AP1, HC2 and AP2, HC3 and AP3 were treated with 99.9%, 70% and 40% respectively for 30, 60 and 120s followed by analysis of surface roughness (Sa), topographical changes and some nanomechanical properties. RESULTS: Both HC and AP resins showed changes in their Sa and nanomechanically measured modulus of elasticity and surface hardness after being treated at different concentrations of ethanol and at different lengths of time. Surface changes were most clearly seen in autopolymerizing denture base polymer, especially at the interface region between the PMMA polymer bead and polymer matrix. There was a correlation (R2=0.83, r=0.91, P<0.001) between the time of treatment by ethanol and thickness of the affected area of denture base polymer. CONCLUSION: The present study demonstrated that denture base polymers, especially autopolymerized denture base polymer is prone for surface crazing and dissolving by solvent/disinfectant ethanol. The interphase region between the PMMA polymer bead and the polymer matrix was most affected by the ethanol.

Outcome of Palliative and Radical Radiotherapy in Patients with Oral Squamous Cell Carcinoma - a Retrospective Study.

BACKGROUND: The treatment selection for the oral squamous cell carcinoma remains controversial. Radiation therapy or surgical excision of the lesion can be applied as the sole treatment or it can be used in combination with other treatment modalities. Radiotherapy is considered to be the safest of all the treatment modalities and can be used in several situations for oral and oropharyngeal cancers. The aim of this study was to evaluate the survival outcome differences in patients treated with radical and palliative radiotherapy as the primary treatment modality. MATERIALS AND METHODS: The study included a total of 47 patients with oral cancer reporting to our hospital between years 2009 to 2010. The age group for the selected patients was more than 65 years, treated with radical and palliative radiotherapy with no prior surgical interventions. Patients were evaluated till Dec 2013 for overall survival time. RESULTS: Twenty nine patients were treated with radical radiotherapy as main stay of treatment, out of which 21 died during the follow up time with median survival of 352 ± 281.7 days with 8 patients alive. All the 16 patients were dead who received palliative radiotherapy with a median survival time of 112 ± 144.0 days. CONCLUSIONS: This retrospective study showed improved overall survival time, loco regional control rates and reduced morbidity in patients treated with radical radiotherapy when compared to patients treated with palliative radiotherapy.