Design and fabrication of a magnetic nanobiocomposite based on flaxseed mucilage hydrogel and silk fibroin for biomedical and in-vitro hyperthermia applications

In this research work, a magnetic nanobiocomposite is designed and presented based on the extraction of flaxseed mucilage hydrogel, silk fibroin (SF), and Fe3O4 magnetic nanoparticles (Fe3O4 MNPs). The physiochemical features of magnetic flaxseed mucilage hydrogel/SF nanobiocomposite are evaluated by FT-IR, EDX, FE-SEM, TEM, XRD, VSM, and TG technical analyses. In addition to chemical characterization, given its natural-based composition, the in-vitro cytotoxicity and hemolysis assays are studied and the results are considerable. Following the use of highest concentration of magnetic flaxseed mucilage hydrogel/SF nanobiocomposite (1.75 mg/mL) and the cell viability percentage of two different cell lines including normal HEK293T cells (95.73%, 96.19%) and breast cancer BT549 cells (87.32%, 86.9%) in 2 and 3 days, it can be inferred that this magnetic nanobiocomposite is biocompatible with HEK293T cells and can inhibit the growth of BT549 cell lines. Besides, observing less than 5% of hemolytic effect can confirm its hemocompatibility. Furthermore, the high specific absorption rate value (107.8 W/g) at 200 kHz is generated by a determined concentration of this nanobiocomposite (1 mg/mL). According to these biological assays, this magnetic responsive cytocompatible composite can be contemplated as a high-potent substrate for further biomedical applications like magnetic hyperthermia treatment and tissue engineering.

Polarization dependent light propagation in [Formula: see text] multilayer structure

[Formula: see text] is one of the exciting and outstanding semimetallic members of TMDCs, which has attracted immense attention for manipulating light propagation due to its inherent optical anisotropy and hyperbolic characteristic in the infrared frequency range. We investigate the dependence of the reflectance and transmittance of structures with a single and double [Formula: see text] thin film in terms of frequency and polarization angle of the incident wave. We find rich behaviors in the optical response of these structures due to their anisotropic permittivity tensors. Furthermore, we analyze the polarization state of transmitted and reflected waves through these structures. We demonstrate that these structures provide the ability to achieve desired polarization rotation for outgoing waves by tuning the frequency and polarization angle of the incident wave with respect to the principal axes of [Formula: see text] thin film. In particular, we elucidate the essential relevance of the optical response and polarization rotation of the double thin film structure to the in-plain twist angle of [Formula: see text] thin films. We explain that this structure permits comprehensive control of the polarization rotation of the outgoing waves by adjusting the twist angle of thin films. The proposed structure can be employed as an efficient light manipulator with the aim of application in communication, imaging, and information processing.

Valley-optical absorption in planar transition metal dichalcogenide superlattices

In this study, we investigate the optical absorption of a planar superlattice comprising alternatively arranged two-dimensional Transition Metal DiChalcogenide semiconductors. Within a semi-classical model and using the Dirac-like equation in the presence of light interaction as a perturbation, we obtained the governing Hamiltonian. Using this Hamiltonian, we derived a fully analytical relationship for the absorption coefficient of the structure. By calculating the effective mass for different bands and using the Drude-Lorentz model, our approach is able to determine the oscillator strength and the effective refractive index of the structure. We found that the spin-orbit coupling has important effect on the absorption coefficient and energy bands where it reduces the absorption coefficient of the structure from typical value of [Formula: see text]-[Formula: see text], also the valence band experiences a significant blue shift, while the conduction band shows minor changes due to spin orbit coupling. Moreover, the role of incident light angle and light polarization were studied in details at different valleys of [Formula: see text] and [Formula: see text]. The most important finding is that by changing the polarization of incident light, it is possible to increase the absorption coefficients of [Formula: see text] and [Formula: see text] valleys by up to 30 times. For light propagation direction close to perpendicular to the plane of the superlattice, the right-circular polarization is absorbed only by [Formula: see text] valley in contrast to the left-circular polarization, which is absorbed by the [Formula: see text] valley. Our model might be used to design newly developed 2D optovalleytronic devices.

Nano-Based Theranostic Platforms for Breast Cancer: A Review of Latest Advancements

Breast cancer (BC) is a highly metastatic multifactorial disease with various histological and molecular subtypes. Due to recent advancements, the mortality rate in BC has improved over the past five decades. Detection and treatment of many cancers are now possible due to the application of nanomedicine in clinical practice. Nanomedicine products such as Doxil^® and Abraxane^® have already been extensively used for BC adjuvant therapy with favorable clinical outcomes. However, these products were designed initially for generic anticancer purposes and not specifically for BC treatment. With a better understanding of the molecular biology of BC, several novel and promising nanotherapeutic strategies and devices have been developed in recent years. In this context, multi-functionalized nanostructures are becoming potential carriers for enhanced chemotherapy in BC patients. To design these nanostructures, a wide range of materials, such as proteins, lipids, polymers, and hybrid materials, can be used and tailored for specific purposes against BC. Selective targeting of BC cells results in the activation of programmed cell death in BC cells and can be considered a promising strategy for managing triple-negative BC. Currently, conventional BC screening methods such as mammography, digital breast tomosynthesis (DBT), ultrasonography, and magnetic resonance imaging (MRI) are either costly or expose the user to hazardous radiation that could harm them. Therefore, there is a need for such analytical techniques for detecting BC that are highly selective and sensitive, have a very low detection limit, are durable, biocompatible, and reproducible. In detecting BC biomarkers, nanostructures are used alone or in conjunction with numerous molecules. This review intends to highlight the recent advances in nanomedicine in BC treatment and diagnosis, emphasizing the targeting of BC cells that overexpress receptors of epidermal growth factors. Researchers may gain insight from these strategies to design and develop more tailored nanomedicine for BC to achieve further improvements in cancer specificity, antitumorigenic effects, anti-metastasis effects, and drug resistance reversal effects.

Robust tunable excitonic features in monolayer transition metal dichalcogenide quantum dots

The effects of quantum confinement on excitons in parabolic quantum dots of monolayer transition metal dichalcogenides (TMDC QDs) are investigated within a massive Dirac fermion model. A giant spin-valley coupling of the TMDC QDs is obtained, larger than that of monolayer TMDC sheets and consistent with recent experimental measurements. The exciton transition energy and the binding energy are calculated, and it is found that the strong quantum confinement results in extremely high exciton binding energies. The enormously large exciton binding energy in TMDC QDs ([Formula: see text] for different kinds of TMDC QDs) ensures that the many body interactions play a significant role in the investigation of the optical properties of these novel nanostructures. The estimated oscillator strength and radiative lifetime of excitons are strongly size-dependent and indicate a giant oscillator strength enhancement and ultrafast radiative annihilation of excitons, varying from a few tens of femtoseconds to a few picoseconds. We found that the spin-dependent band gap, spin-valley coupling, binding energy and excitonic effects can be tuned by quantum confinements, leading to tunable quantum dots in monolayer TMDCs. This finding offers new functionality in engineering the interaction of a 2D material with light and creates promise for the quantum manipulation of spin and valley degrees of freedom in TMDC nanostructures, enabling versatile novel 2D quantum photonic and optoelectronic nanodevices.

Breast Cancer Cell Apoptosis is Synergistically Induced by Curcumin, Trastuzumab, and Glutathione Peroxidase-1 but Robustly Inhibited by Glial Cell Line-Derived Neurotrophic Factor

We hypothesized that synergy between curcumin (CURC), trastuzumab (TZMB), and glutathione peroxidase-1 (GPX-1) accelerates breast cancer (BC) cell apoptosis which is inhibited by glial cell line-derived neurotrophic factor (GDNF). We measured survival of BC cell lines treated or cotreated with CURC and TZMB, and then with GDNF, before measuring expression levels of growth and apoptosis genes. These experiments were also repeated on SKBR3 cells transiently expressing GPX-1. CURC+TZMB cotreatment induced BC cell apoptosis more significantly than single treatment. GDNF highly inhibited CURC+TZMB toxicity and restored survival. Ectopic overexpression of GPX-1 per se induced SKBR3 cell death that was accelerated upon CURC+TZMB cotreatment. This substantial death induction was inhibited by GDNF more robustly than in single-treated cells. All these changes correlated with changes in expression levels of key molecules and were further confirmed by flow cytometry and correlation analysis. Our data indicate apoptotic induction is jointly shaped in BC cells by CURC, TZMB, and GPX-1 which correlates directly with their tripartite synergism and inversely with GDNF progrowth effects. In light of the active presence of GDNF in tumor microenvironment and necessity to overcome drug resistance, our findings can help in designing combined therapeutic strategies with implications for challenging TZMB resistance in BC.

Pattern Visual Evoked Potentials in Dyslexic Children

PURPOSE

This study aimed to compare pattern visual evoked potential (PVEP) components in dyslexic and normal children.

METHODS

This cross-sectional analytic study recruited 72 children, including 36 dyslexic and 36 normal participants aged 8-12 years. Visual examinations included measurement of distance visual acuity, refraction, and PVEP components of amplitudes and latencies with two different check sizes of 15 and 60 minutes (min) of arc at two contrast levels of 25% and 100%.

RESULTS

Our results demonstrated significant differences between dyslexic and normal children in terms of P100 latency and amplitude of PVEP at 25% contrast, with check sizes of 15 and 60 min of arc. However, there were no significant differences between the two groups regarding P100 latency and amplitude at 100% contrast with check sizes of both 15 and 60 min of arc.

CONCLUSION

Dyslexic participants showed reduced amplitude and prolonged latency in most PVEP components at low-contrast levels. These findings may support the magnocellular deficit hypothesis in dyslexic participants, even though the parvocellular pathway remains intact.

A clinicopathological survey of Basal cell carcinoma in an Iranian population

STATEMENT OF PROBLEM

Basal cell carcinoma (BCC), the most common skin cancer, is a locally invasive malignant epidermal tumor with ulceration and destruction of underlying structures.

PURPOSE

The purpose of this study was clinicopathological evaluation of BCC in the state and the private pathology centers in Hamadan province during 1990-2010.

MATERIALS AND METHOD

In this retrospective study all histopathologically proven cases of BCC were reviewed and the related information including age, gender, place of residency and number of tumors for the patients alongside with the site of occurrence, size, histopathological and clinical type of the lesions were collected and then statistically analyzed, using SPSS software.

RESULTS

A total of 804 incidents of BCC were diagnosed in 746 patients (296 females and 450 males) with the most affected site being in the head-face (84.8%), neck (2.6%), trunk (1.6%) and limbs (0.9 %) and 10.1% cases with unknown site. The mean age for the patients was 61.77±13.75 years (63.07± 13.44 for males, 59.81 ± 14.01 for females) and the highest frequency (27.2%) occurred among 60-69 years age group. Nodular type was the most common clinical and histopathological BCC lesions studied whereas the mean size of the lesions was 15.67 ± 11.06 mm with more frequency rate in urban than rural regions.

CONCLUSION

This study focuses on the survey of BCC in Hamadan province but regarding to insufficiency of the data collected by state and provincial pathology centers about the BCC cases reported; it is highly recommended to apply comprehensive questionnaire, which are designated by skillful professionals who are familiar with the lesion nationally.

Effects of Soy on Body Composition: A 12-Week Randomized Controlled Trial among Iranian Elderly Women with Metabolic Syndrome

BACKGROUND

To examine the effects of soy [in the form of textured soy protein (TSP) and soy-nut] on body composition in elderly women with metabolic syndrome (MetS).

METHODS

A 12-week randomized clinical trial was conducted on 75 women between 60-70 years of age with MetS in rural health clinics around Babol, Iran in 2009. The participants were randomly assigned to one of the three groups of soy-nut (35g/d), TSP (35g/d) and control. Body fat, lean mass and anthropometric indicators were measured before and after intervention, too.

RESULTS

Participants were classified as overweight and showing android fat distribution. After 12 weeks of intervention, both soy-nut and TSP groups showed an increase of non-significant in lean mass (0.9 and 0.7 kg), hip circumference (0.45 and 0.28 cm), triceps skinfold (TSF) thickness (0.87 and 0.67mm) and reduction in BMI (-0.15 and -0.33), waist circumference (-0.83 and -1.2) and body fat (-1.5% and -1.7%). Significant increase in the mean change of TSF and lean mass was observed in the users of soy-nut compared to the control group (P<0.01, P<0.05).

CONCLUSION

12-week intervention of soy had a mild favorable effect on body composition in elderly women with MetS.