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In this work, an electrochemical aptasensor was described for the determination of prostate-specific antigen (PSA). Aptamer chains were decorated on the surface of a glassy carbon electrode (GCE) via carbon quantum dots/Au nanoparticles (Au/CQD). Structural analysis that was used to characterize the prepared materials shows that Au/CQD nanoparticles synthesized in a spherical shape with an average size of 70 nm. Furthermore, the combination of Au nanoparticles with CQD resulted in formation of crystalline the structure of the Au/CQD composite. To study the electrochemical performance of the prepared aptasensor, cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy were used. The results show that the aptasensor has a good selectivity to PSA over other biomaterials with the time optimized about 30 min. K

The Trachyspermum copticum essential oil (TCEO) has been incorporated into niosomes (NIO-TCEO). The chemical composition of the TCEO has been evaluated using Gas chromatography mass spectrometry (GC-MS) and the antioxidant activity of the TCEO has been characterized by radical scavenging capacity (RSC). The niosomes have been characterized with respect to their size, zeta potential, morphology, encapsulation efficiency, in vitro release, and cell toxicity against hepatocellular carcinoma cell line (HepG2). The interaction of the TCEO with niosomes has been studied using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Our study has shown an excellent antioxidant activity of the essential oil with IC50 of 18.32 ± 3.6 μg/ml. The size of the niosomes has been around 151.06 ± 5.3 nm and the TCEO entrapment efficiency has been 87.41 ± 5.97%. Our results have demonstrated that niosomes loaded with TCEO have a potential application for cancer therapy.

ObjectiveTo evaluate clinical, interferon and imaging predictors of progression from ‘At Risk’ to autoimmune connective tissue diseases (AI-CTDs).MethodsA prospective observational study was conducted in At-Risk of AI-CTD (defined as antinuclear antibody (ANA) positive; ≤1 clinical systemic lupus erythematosus (SLE) criterion; symptom duration Results118 individuals with 12-month follow-up were included. Of these, 19/118 (16%) progressed to AI-CTD (SLE=14, primary Sjogren’s=5). At baseline, both IFN scores differed among At-Risk, HCs and SLE groups (pConclusionA two-factor interferon score and family history predict progression from ANA positivity to AI-CTD. These interferon scores may allow stratification of individuals At-Risk of AI-CTD permitting early intervention for disease prevention and avoid irreversible organ damage.

Improving bone regeneration is one of the most pressing problems facing bone tissue engineering (BTE) which can be tackled by incorporating different biomaterials into the fabrication of the scaffolds. The present study aims to apply the 3D-printing and freeze-drying methods to design an ideal scaffold for improving the osteogenic capacity of Dental pulp stem cells (DPSCs). To achieve this purpose, hybrid constructs consisted of 3D-printed Beta-tricalcium phosphate (β-TCP)-based scaffolds filled with freeze-dried gelatin/reduced graphene oxide-Magnesium-Arginine (GRMA) matrix were fabricated through a novel green method. The effect of different concentrations of Reduced graphene oxide-Magnesium-Arginine (RMA) (0, 0.25% and 0.75%wt) on the morphology, mechanical properties, and biological activity of the 3D scaffolds were completely evaluated. Our findings show that the incorporation of RMA hybrid into the scaffold can remarkably enhance its mechanical features and improve cell proliferation and differentiation simultaneously. Of all scaffolds, β-TCP/0.25GRMA showed not only the highest ALP activity and cell proliferation after 14 days but it up-regulated bone-related genes and proteins (COL-I, RUNX2, OCN). Hence, the fabricated 3D printed β-TCP/0.25GRMA porous scaffolds can be considered as a high-potential candidate for BTE.

Photothermal therapy with various nanoparticles, as photothermal transducers, is a widely researched technique. A continuous wave (CW) laser is employed during this procedure. The therapeutic setup is slightly modified to measure the optical absorption cross-section of the graphene oxide (GO), by mitigating the effects of heat diffusion and light scattering. With an 808-nm CW laser setup modulated by a waveform modulation setup, the effect of nanoparticle size and composition of GO in water on optical absorption cross section is characterized.

This paper describes the design of stimuli-sensitive theranostic nanoparticles, composed of reduced graphene oxide (rGO) self-assembled on thermosensitive liposomes encapsulated doxorubicin (DOX) and carbon quantum dot (CQD) (CQD-DOX-rGO-Tlip). The rGO-Tlip particles have been observed to be flower-shaped objects. The thermoresponsive and theranostic potential of CQD-DOX-rGO-Tlips have been studied using differential scanning calorimetry (DSC), ultraviolet visible spectroscopy (UV-Vis), Raman spectroscopy and photoluminescent assays. The chemo-photothermal potential of rGO-Tlip on MD-MB-231 cells during NIR laser irradiation has been examined using MTT assay. Also, the ability of rGO-Tlip to be taken up by MD-MB-231 cells has been studied using confocal microscopy and flowcytometry. The results indicate that CQD-DOX-rGO-Tlips achieve a synergistic effect between photothermal therapy and chemotherapy for cancer treatment. Furthermore, online monitoring drug release is accomplished by studying the emission intensity of CQD while DOX released.

ObjectiveWhen faced with clinical symptoms of scarring alopecia—the standard diagnostic pathway involves a scalp biopsy which is an invasive and expensive procedure. This project aimed to assess if plucked hair follicles (HFs) containing living epithelial cells can offer a non-invasive approach to diagnosing inflammatory scalp lesions.MethodsLesional and non-lesional HFs were extracted from the scalp of patients with chronic discoid lupus erythematosus (CDLE), psoriasis and healthy controls. RNA was isolated from plucked anagen HFs and microarray, as well as quantitative real-time PCR was performed.ResultsHere, we report that gene expression analysis of only a small number of HF plucked from lesional areas of the scalp is sufficient to differentiate CDLE from psoriasis lesions or healthy HF. The expression profile from CDLE HFs coincides with published profiles of CDLE from skin biopsy. Genes that were highly expressed in lesional CDLE corresponded to well-known histopathological diagnostic features of CDLE and included those related to apoptotic cell death, the interferon signature, complement components and CD8+ T-cell immune responses.ConclusionsWe therefore propose that information obtained from this non-invasive approach are sufficient to diagnose scalp lupus erythematosus. Once validated in routine clinical settings and compared with other scarring alopecias, this rapid and non-invasive approach will have great potential for paving the way for future diagnosis of inflammatory scalp lesions.

Senile graying of human hair has been the subject of intense research since ancient times. Reactive oxygen species have been implicated in hair follicle melanocyte apoptosis and DNA damage. Here we show for the first time by FT-Raman spectroscopy in vivo that human gray/white scalp hair shafts accumulate hydrogen peroxide (H(2)O(2)) in millimolar concentrations. Moreover, we demonstrate almost absent catalase and methionine sulfoxide reductase A and B protein expression via immunofluorescence and Western blot in association with a functional loss of methionine sulfoxide (Met-S=O) repair in the entire gray hair follicle. Accordingly, Met-S=O formation of Met residues, including Met 374 in the active site of tyrosinase, the key enzyme in melanogenesis, limits enzyme functionality, as evidenced by FT-Raman spectroscopy, computer simulation, and enzyme kinetics, which leads to gradual loss of hair color. Notably, under in vitro conditions, Met oxidation can be prevented by L-methionine. In summary, our data feed the long-voiced, but insufficiently proven, concept of H(2)O(2)-induced oxidative damage in the entire human hair follicle, inclusive of the hair shaft, as a key element in senile hair graying, which does not exclusively affect follicle melanocytes. This new insight could open new strategies for intervention and reversal of the hair graying process.

Vitiligo is characterized by a patchy loss of inherited skin color affecting approximately 0.5% of individuals of all races. Despite the absence of the protecting pigment and the overwhelming evidence for hydrogen peroxide (H(2)O(2))-induced oxidative stress in the entire epidermis of these patients, there is neither increased photodamage/skin aging nor a higher incidence for sun-induced nonmelanoma skin cancer. Here we demonstrate for the first time increased DNA damage via 8-oxoguanine in the skin and plasma in association with epidermal up-regulated phosphorylated/acetylated p53 and high levels of the p53 antagonist p76(MDM2). Short-patch base-excision repair via hOgg1, APE1, and polymerasebeta DNA repair is up-regulated. Overexpression of Bcl-2 and low caspase 3 and cytochrome c levels argue against increased apoptosis in this disease. Moreover, we show the presence of high epidermal peroxynitrite (ONOO(-)) levels via nitrotyrosine together with high nitrated p53 levels. We demonstrate by EMSA that nitration of p53 by ONOO(-) (300 x 10(-6) M) abrogates DNA binding, while H(2)O(2)-oxidized p53 (10(-3) M) enhances DNA binding capacity and prevents ONOO(-)-induced abrogation of DNA binding. Taken together, we add a novel reactive oxygen species to the list of oxidative stress inducers in vitiligo. Moreover, we propose up-regulated wild-type p53 together with p76(MDM2) as major players in the control of DNA damage/repair and prevention of photodamage and nonmelanoma skin cancer in vitiligo.

Xanthine dehydrogenase/xanthine oxidase (XDH/XO) catalyses the hydroxylation of hypoxanthine to xanthine and finally to uric acid in purine degradation. These reactions generate H(2)O(2) yielding allantoin from uric acid when reactive oxygen species accumulates. The presence of XO in the human epidermis has not been shown so far. As patients with vitiligo accumulate H(2)O(2) up to mm levels in their epidermis, it was tempting to examine whether this enzyme and consequently allantoin contribute to the oxidative stress theory in this disease. To address this question, reverse transcription-polymerase chain reaction, immunoreactivity, western blot, enzyme kinetics, computer modelling and high performance liquid chromatography/mass spectrometry analysis were carried out. Our results identified the presence of XDH/XO in epidermal keratinocytes and melanocytes. The enzyme is regulated by H(2)O(2) in a concentration-dependent manner, where concentrations of 10(-6 )m upregulates the activity. Moreover, we demonstrate the presence of epidermal allantoin in acute vitiligo, while this metabolite is absent in healthy controls. H(2)O(2)-mediated oxidation of Trp and Met in XO yields only subtle alterations in the enzyme active site, which is in agreement with the enzyme kinetics in the presence of 10(-3 )m H(2)O(2). Systemic XO activities are not affected. Taken together, our results provide evidence that epidermal XO contributes to H(2)O(2)-mediated oxidative stress in vitiligo via H(2)O(2)-production and allantoin formation in the epidermal compartment.