In recent years, induced pluripotent stem cells (iPSCs) have been considered as a promising approach in the field of regenerative medicine. iPSCs can be generated from patients’ somatic cells and possess the potential to differentiate, under proper conditions, into any cell type. However, the clinical application of iPS cells is restricted because of their tumorigenic potential. Recent studies have indicated that stem cells exert their therapeutic benefit via a paracrine mechanism, and extracellular vesicles have been demonstrated that play a critical role in this paracrine mechanism. Due to lower immunogenicity, easier management, and presenting no risk of tumor formation, in recent years, researchers turned attention to exosomes as potential alternatives to whole‐cell therapy. Application of exosomes derived from iPSCs and their derived precursor provides a promising approach for personalized regenerative medicine. This study reviews the physiological functions of extracellular vesicles and discusses their potential therapeutic benefit in regenerative medicine.

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Magnetic iron oxide nanoparticles are a well‐explored class of nanomaterials known for their high magnetization and biocompatibility. They have been used in various biomedical applications such as drug delivery, biosensors, hyperthermia, and magnetic resonance imaging (MRI) contrast agent. It is necessary to surface modify the nanoparticles with a biocompatible moiety to prevent their agglomeration and enable them to target to the defined area. Dendrimers have attracted considerable attention due to their small size, monodispersed, well‐defined globular shape, and a relative ease incorporation of targeting ligands. In this study, superparamagnetic iron oxide nanoparticles were synthesized via a coprecipitation method. The magnetic nanoparticles (MNPs) had been modified with (3‐aminopropyl) triethoxysilane, and then polyamidoamine functionalized MNPs had been synthesized cycling. Various characterization techniques had been used to reveal the morphology, size, and structure of the nanoparticles such as scanning electron microscopy, transmission electron microscope, X‐ray diffraction analysis, and vibrating sample magnetometer, Fourier‐transform infrared spectroscopy and zeta potential measurements. In addition, the cytotoxicity property of G3–dendrimer functionalized MNPs were evaluated using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2, 5‐diphenyl tetrazolium bromide assay which confirmed the biocompatibility of the nanocomposites. Dendrimer functionalized MNPs are able to act as contrast agents for MRI and magnetic fluid hyperthermia mediators. A superior heat generation was achieved for the given concentration according to the hyperthermia results. MRI results show that the synthesized nanocomposites are a favorable option for MRI contrast agent. We believe that these dendrimer functionalized MNPs have the potential of integrating therapeutic and diagnostic functions in a single carrier.

Mimicking the structure of extracellular matrix and electrical conductivity of myocardium are required to regenerate the functional cardiac tissue. In this study, Molybdenum disulfide, MoS2, nanosheets were synthesized and incorporated into nylon6 electrospun nanofibers in order to enhance the mechanical properties and electrical conductivity of the scaffolds. Then, the mouse embryonic cardiac cells, mECCs, were seeded on the scaffolds for in vitro studies. The MoS2 nanosheets were studied by scanning electron microscopy (SEM) and Raman spectroscopy. Nylon/MoS2 nanofibers were characterized by SEM, transmission electron microscopy (TEM), water contact angle measurement, electrical conductivity, and tensile test. Furthermore, cytocompatibility of scaffolds was confirmed by 3‐(4, 5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide, MTT, assay. SEM images showed more elongated morphology for mECCs attached to the nylon/MoS2 scaffold. Also, the Real‐Time PCR and immunostaining studies indicated the maturation and upregulation of cardiac functional genes including GATA‐4, c‐TnT, Nkx 2.5 and α‐MHC in the nylon/MoS2 scaffold in comparison to the bare nylon. Therefore, MoS2 reinforced nylon nanofibrous scaffolds can be considered as a suitable candidate in cardiac tissue engineering.

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Background Aims Sepsis and related disorders, especially acute lung injury (ALI), are the most challenging life‐threatening diseases in the hospital intensive care unit. Complex pathophysiology, unbalanced immune condition, and high rate of mortality complicate the treatment of sepsis. Recently, cell therapy has been introduced as a promising option to recover the sepsis symptoms. The aim of this study was to investigate the therapeutic potential of human unrestricted somatic stem cells (USSCs) isolated from human umbilical cord blood in the mouse model of ALI. USSCs significantly enhanced the survival rate of mice suffering from ALI and suppressed concentrations of proinflammatory mediators TNF‐α, and interleukin (IL)‐6, and the level of anti‐inflammatory cytokine IL‐10. ALI mice injected by USSCs showed notable reduction in lung and liver injury, pulmonary edema, and hepatic enzymes, compared with the control group. These results determined the in vivo immunomodulatory effect of USSCs for recovery of immune balance and reduction of tissue injury in the mouse model of ALI. Therefore, USSCs can be a suitable therapeutic approach to manage sepsis disease through the anti‐inflammatory potential.

Umbilical cord blood (UCB) hematopoietic stem cells (HSCs) transplantation (HSCTs) is considered as a therapeutic strategy for malignant and nonmalignant hematologic disorders. Nevertheless, the low number of HSCs obtained from each unit of UCB can be a major challenge for using these cells in adults. In addition, UCB is a rich source of mesenchymal stem cells (MSCs) creating hopes for nonaggressive and painless treatment in tissue engineering compared with bone marrow MSCs. This study was designed to evaluate the effects of UCB-MSCs application in UCB-HSCs expansion on the nanoscaffold that mimics the cell's natural niche. To achieve this goal, after flow cytometry confirmation of isolated HSCs from UCB, they were expanded on three-dimensional (3D) poly-L-lactic acid (PLLA) scaffolds fabricated by electrospinning and two-dimensional (2D)-culture systems, such as (1) HSCs-MSCs culturing on the scaffold, (2) HSCs culturing on the scaffold, (3) HSCs-MSCs culturing on 2D, and (4) HSCs culturing on 2D. After 7 days, real-time polymerase chain reaction (PCR) was performed to evaluate the CXCR4 gene expression in the mentioned groups. Moreover, for the next validation, the number of total HSCs, 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide assay, scanning electron microscopy imaging, and colonyforming unit assay were evaluated as well. The results of the study indicated that UCB-MSCs interaction with HSCs in 3D-culture systems led to the highest expansion of UCB-HSCs on day 7. Flow cytometry results showed the highest purity of HSCs cocultured with MSCs. Real-time PCR showed a significant increase in gene expression of CXCR4 in the mentioned group. The highest viability and clonogenicity were detected in the mentioned group too. Considered together, our results suggest that UCB-HSCs and MSCs coculturing on PLLA scaffold could provide a proper microenvironment that efficiently promotes UCB-HSCs expansion and UCB-MSCs can also be considered as a promising candidate for UCB-HSCTs.

Gastroenteritis, as one of the main worldwide health challenges, especially in children, leads to 3–6 million deaths annually and causes nearly 20% of the total deaths of children aged ˂5 years, of which ~1.5 million gastroenteritis deaths occur in developing nations. Viruses are the main causative agent (~70%) of gastroenteritis episodes and their specific and early diagnosis via laboratory assays is very helpful for having successful antiviral therapy and reduction in infection burden. Regarding this importance, the present literature is the first review of updated improvements in the employing of different types of biosensors such as electrochemical, optical, and piezoelectric for sensitive, simple, cheap, rapid, and specific diagnosis of human gastroenteritis viruses. The Introduction section is a general discussion about the importance of viral gastroenteritis, types of viruses that cause gastroenteritis, and reasons for the combination of conventional diagnostic tests with biosensors for fast detection of viruses associated with gastroenteritis. Following the current laboratory detection tests for human gastroenteritis viruses and their limitations (with subsections: Electron Microscope (EM), Cell Culture, Immunoassay, and Molecular Techniques), structural features and significant aspects of various biosensing methods are discussed in the Biosensor section. In the next sections, basic information on viruses causing gastroenteritis and recent developments for fabrication and testing of different biosensors for each virus detection are covered, and the prospect of future developments in designing different biosensing platforms for gastroenteritis virus detection is discussed in the Conclusion and Future Directions section as well.