Ahmad Vaez

Microbubbles are typically 0.5-10 μm in size. Their size tends to make it easier for medication delivery mechanisms to navigate the body by allowing them to be swallowed more easily. The gas included in the microbubble is surrounded by a membrane that may consist of biocompatible biopolymers, polymers, surfactants, proteins, lipids, or a combination thereof. One of the most effective implementation techniques for tiny bubbles is to apply them as a drug carrier that has the potential to activate ultrasound (US); this allows the drug to be released by US. Microbubbles are often designed to preserve and secure medicines or substances before they have reached a certain area of concern and, finally, US is used to disintegrate microbubbles, triggering site-specific leakage/release of biologically active drugs. They have excellent therapeutic potential in a wide range of common diseases. In this article, we discussed microbubbles and their advantageous medicinal uses in the treatment of certain prevalent disorders, including Parkinson's disease, Alzheimer's disease, cardiovascular disease, diabetic condition, renal defects, and finally, their use in the treatment of various forms of cancer as well as their incorporation with nanoparticles. Using microbubble technology as a novel carrier, the ability to prevent and eradicate prevalent diseases has strengthened the promise of effective care to improve patient well-being and life expectancy.

Background: Polymeric scaffolds have achieved immense importance in the field of nerve tissue engineering. Methods: In the present study, the combination of thermally induced phase separation (TIPS) and electrospinning methods were used to fabricate poly-(lactic acid)/gelatin nanofiber/PRP-scaffolds. Several physical and mechanical tests (weight loss measurement, surface wettability, porosity, microstructure observation via SEM photography, mechanical tests such as tensile strength, and Young modulus) and cellular assays (MTT assay and DAPI staining) were explored to assess the scaffolds capability to serve as neural guidance conduit. In this study, we hypothesized that conduits enriched with PRP may provide a better regenerative environment for nerve tissue repair. Results: This study suggests that GTNF/PRP incorporated scaffolds revealed better biological and physical properties than PLA only scaffolds. Conclusions: Results indicate that when GTNF/PRP is incorporated into the PLA scaffolds, resultant mechanical properties, porosity and cell attachment, and viability in vitro were better than pure PLA.

This is the first study demonstrating the efficacy of menstrual blood-derived stem cell (MenSC) transplantation via a neural guidance conduit, for peripheral nerve regeneration. The synthesized poly (ɛ-caprolactone)/Gelatin conduit, filled with collagen type I and seeded with 3 × 104 MenSCs, was implanted into a rat’s 10 mm sciatic nerve defect. The results of hot plate latency, sciatic functional index and weight-loss percentage of wet gastrocnemius muscle demonstrated that the MenSC transplantation had comparable nerve regeneration outcome to autograft, as the gold standard of nerve bridging. The transplantation of MenSCs via a synthetic conduit could ameliorate the functional recovery of sciatic nerve-injured rats which make them a potential candidate for cell therapy of peripheral nervous system disorders.

In the current study, insulin delivering chitosan nanoparticles were coated onto the electrospun poly (ε-caprolactone) (PCL)/Collagen (COLL) to produce a potential wound care material. Electrospun matrices were fabricated from PCL/COLL (1:1 (w/w)) solution. The insulin-loaded chitosan nanoparticles were produced by ionic gelation process and then attached onto the yarns. The dressings were investigated regarding their surface wettability, microstructure, the capacity to absorb water, water vapour permeability, mechanical properties, blood compatibility, microbial penetration, and cellular behavior. Full-thickness excisional wound model was used to assess the in vivo healing capacity of the dressings. Our data showed that after 14 days the wounds covered with PCL/COLL/Cs-Ins wound dressing could reach to nearly full wound closure compared with the sterile gauze which exhibited nearly 45% of wound size reduction. Our results suggest that fabricated scaffolds can be potentially applied in clinical practice for wound treatment.

In the current study, tetracycline hydrochloride (TCH), an antibiotic against most of the medically relevant bacteria, was incorporated into poly (ε-caprolactone)/poly lactic acid solution in order to develop a composite scaffold with both antibacterial and osteoinductive properties for the repair of infected bone defects. The composite scaffolds were produced from poly (ε-caprolactone) (PCL) and poly lactic acid (PLA) solution (1:1 (w/w)) incorporated with 3, 5, and 10% (w/w) of TCH by thermally induced phase separation technique. The scaffolds were evaluated regarding their morphology, wettability, porosity, degradation, mechanical properties, and cellular response. The scaffold containing 10% of TCH (PCL/PLA/TCH10%) was chosen as the optimum scaffold for further investigation in a rat femoral defect model. The study showed that after eight weeks, the bone formation was relatively higher in PCL/PLA/TCH10%-treated group with completely filled defect when compared with control (PCL/PLA scaffold without TCH). Histopathological evaluation showed that the defect in PCL/PLA/TCH10%-treated group was fully replaced by new bone and connective tissue. Our results provide evidence supporting the possible applicability of TCH-containing scaffolds for successful bone regeneration.

In the present study, naringin, a flavonoid isolated from the grape and citrus fruit species, was incorporated with poly(ε-caprolactone)/gelatin composite mats in order to develop a potential wound dressing. The composite mats were prepared by electrospinning of poly(ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 1.50 %, 3 % and 6 % (w/w) of naringin. The electrospun mats were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile properties, drug release, cellular response and in vivo wound healing activity. The study showed that after 2 weeks, the full-thickness excisional wounds of Wistar rats treated with the naringin-loaded dressings achieved a wound closure of higher than 94 % and the dressing containing 6 % (w/w) naringin had almost 100 % wound closure. The sterile gauze, as the control group, showed nearly 86 % of wound closure after this period of time. Our results provided evidence that supports the possible applicability of naringin-loaded wound dressing for successful wound treatment.

In the present study, gabapentin (GBP), an anticonvulsant drug used as an analgesic to control the neuropathic pains, was incorporated with cellulose acetate (CA) and gelatin (Gel) in order to develop a potential scaffold for neural tissue engineering applications. The wet-electrospinning method was used to produce the drug-loaded three-dimensional scaffolds from CA/Gel [1:1 (w/w)] solution in the water/ethanol (3:7) (v/v) coagulation baths containing 3%, 6% and 12% (w/v) of GBP. The scaffolds were evaluated regarding their morphology, contact angle, porosity, tensile strength and cellular response. The scaffold obtained from 6% (w/v) GBP bath was chosen as the optimum scaffold for further in vivo study in a sciatic nerve defect model in Wistar rats. The results of sciatic functional index, hot plate latency, weight-loss percentage of the wet gastrocnemius muscle and the histopathological examination using hematoxylin-eosin staining demonstrated that the GBP-containing scaffold significantly enhanced the regeneration of the created injury, which demonstrates its applicability for neural tissue engineering applications.

This study aimed to develop a recombinant human erythropoietin/aloe vera gel–releasing polyvinyl alcohol/chitosan wound dressing by wet-electrospinning method and investigate the synergistic effects of erythropoietin and aloe vera gel on the excisional wound healing. The polyvinyl alcohol/chitosan (4:1 (w/w)) solution was electrospun into an aloe vera gel–containing water coagulation bath and then coated with the recombinant human erythropoietin–loaded chitosan nanoparticles prepared via ionic gelation technique. The developed sponge-like film was able to release the erythropoietin and aloe vera gel for at least 7 and 1 days, respectively. The dressing was non-toxic to L929 fibroblastic cell line and non-adherent to the wound bed with the contact angle of 67.93° ± 2.31°. It also possessed the water-uptake capacity and water vapor transmission rate of 26.40% ± 3.37% and 2584.00 ± 144.67 g m−2, respectively. The in vivo study demonstrated the synergistic wound-healing effects of aloe vera gel and erythropoietin on the full-thickness excisional wounds of Wistar rats. The erythropoietin/aloe vera gel–releasing dressing had significantly (n = 4, p < 0.005) higher wound closure (92.96% ± 10.09%) than the sterile gauze (73.89% ± 2.61%), as the control group, after 2 weeks. The differences observed between the wound closure percentages of the aloe vera gel–releasing dressing (85.93% ± 6.46%) and the erythropoietin/aloe vera gel–releasing dressing and control group were not statistically significant.

The current study aimed to enhance the efficacy of peripheral nerve regeneration using a hydroxyapatite nanoparticle-containing collagen type I hydrogel. A solution of type I collagen, extracted from the rat tails, was incorporated with hydroxyapatite nanoparticles (with the average diameter of ~212 nm) and crosslinked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to prepare the hydrogel. The Schwann cell cultivation on the prepared hydrogel demonstrated a significantly higher cell proliferation than the tissue culture plate, as positive control, after 48 h (n = 3, P < 0.005) and 72 h (n = 3, P < 0.01). For in vivo evaluation, the prepared hydrogel was administrated on the sciatic nerve crush injury in Wistar rats. Four groups were studied: negative control (with injury but without interventions), positive control (without injury), collagen hydrogel and hydroxyapatite nanoparticle-containing collagen hydrogel. After 12 weeks, the administration of hydroxyapatite nanoparticle-containing collagen significantly (n = 4, P < 0.005) enhanced the functional behavior of the rats compared with the collagen hydrogel and negative control groups as evidenced by the sciatic functional index, hot plate latency and compound muscle action potential amplitude measurements. The overall results demonstrated the applicability of the produced hydrogel for the regeneration of peripheral nerve injuries.

The present study aimed to evaluate the efficacy of cellulose acetate/gelatin/nanohydroxyapatite (CA/Gel/nHA) nanocomposite mats as the wound dressing. The dressings were prepared with electrospinning of CA/Gel solutions containing 12.5, 25 and 50 mg nHA. The dressings were evaluated regarding their water uptake capacity, morphology, tensile strength, water vapour transmission rate, wettability and cellular response with L929 cell line. The results showed that the concentration of nHA had a direct correlation with porosity, water contact angle, water uptake, water vapor transmission rate and proliferation. In vivo studies showed that all dressings had higher wound closure percent than the sterile gauze, as the control. The highest wound closure value was achieved in the CA/Gel +25 mg nHA group, which showed 93.5 ± 1.6%. The histological and the histomorphometric examinations of the wounds revealed that the CA/Gel +25 mg nHA dressing had the greatest collagen synthesis, re-epithelialization, neovascularization and also the best cosmetic appearance. Based on our finding, it could be concluded the applicability of electrospun nanofibrous CA/Gel/nHA dressings for successful wound treatment.

In this study, taurine (2-aminoethane sulfonic acid), an amino acid found in large amounts in most mammalian tissues, was incorporated with poly (ε-caprolactone) and gelatin in order to develop a drug-loaded composite wound dressing material. The composite mats from poly (ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 3%, 5%, and 10% (w/w) of taurine were produced by electrospinning. The electrospun mats were evaluated regarding their morphology, wettability, water uptake capacity, water vapor transmission rate, tensile strength, and cellular response with L929 cell line. The mat containing 5% of taurine was chosen as the optimum dressing for in vivo study on the full-thickness excisional wounds of Wistar rats. The results showed that after 2 weeks, the wounds treated with the taurine-loaded dressing achieved a significant closure to nearly 92% compared with the sterile gauze, as control, which showed nearly 68% of wound closure. The histological examination of the wounds revealed that the wounds treated with the taurine-loaded dressing had densely packed collagen fibers with parallel alignment. Whereas, the sterile gauze–treated wounds had loosely packed collagen fibers with an irregular arrangement. Our results provided evidence supporting the possible applicability of the taurine-loaded wound dressings for successful wound treatment.

Background: Currently, relation between reactive oxygen species (ROS) ROS concentration and semen quality was indicated. Saffron has traditionally been not only considered as a food additive but also as a medicinal herb, which has a good antioxidant properties. Objective: The aim of this study was to evaluate the protection potency of saffron and vitamin E on sperm chromatin integrity. Materials and Methods: Thirty adult male Wistar rats divided equally into saffron (100 mg/kg), vitamin E (100 mg/kg) and control (0.5cc distilled water /day) groups. After 60 days, cauda epididymis dissected and sperm cells were used for analysis of sperm chromatin packaging by chromomycin A3 (CMA3) staining, and sperm chromatin susceptibility to acid denaturation by acridine orange (AO) staining. Results: The mean percentage of CMA3 positive sperm was significantly decreased in saffron and vitamin E groups relative to control group (p<0.001). Moreover, the AO staining results showed that the mean percentage of sperm with DNA damage was significantly decreased in saffron and vitamin E groups as compared with control group (p<0.001). Conclusion: Our results purposed that saffron can protect sperm against DNA damage and chromatin anomalies.

In the present study, cerium oxide (CeO2) nanoparticles were incorporated into poly (ε-caprolactone)/gelatin films in order to develop a potential wound dressing material. The wound dressings were prepared by electrospinning of poly (ε-caprolactone)/gelatin (1:1 (w/w)) solutions containing 1.50%, 3% and 6% (w/w) CeO2 nanoparticles. The electrospun films were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile strength and cellular response. The film containing 1.50% CeO2 nanoparticles was chosen as the optimal dressing for the in vivo study on full-thickness excisional wounds of rats. The study showed that after 2 weeks, the wounds treated with the CeO2 nanoparticle-containing dressing achieved a significant closure to nearly 100% compared with the sterile gauze with the nearly 63% of wound closure. Our results provided evidence supporting the possible applicability of CeO2 nanoparticle-containing wound dressing for a successful wound treatment.

Due to the restricted potential of the heart to regenerate its damaged region, stem cell therapy is a promising treatment modality for myocardial infarction. It has been shown that incubation of bone marrow-derived stromal cells (BMSCs) with initial steps of cardiac differentiation in vitro, can have a significant effect on their therapeutic potential to treat myocardial infarction. Based on these well-established principals we were encouraged to study the direct co-culture of rat BMSCs with neonatal mouse almost pure cardiomyocytes (APCs) and cardiac niche cells (CNCs) in static 2D and microfluidic cell culture systems. Our results showed that the difference regarding the beating rate in isolated APCs and CNCs in both 2D and the microfluidic system was not statistically significant for 30 days. No beat rate could be observed in induced BMSCs in all groups during experiment time. Except for BMSCs cultured alone in both experimental culture conditions, data obtained from Real-time PCR analysis showed that differentiated BMSCs in all co-cultured groups expressed GATA4, Nkx2.5, CX43, cTnI, cTnT, and β-MHC during 4 weeks. BMSCs demonstrated a higher expression of these cardiac factors in microfluidic chips than those co-cultured in 24 well plates. Moreover, immunocytochemistry (ICC), also revealed the GATA4 expression in differentiated BMSCs in all co-cultured groups. It was found that, when combined with shear stress, co-culture with cardiomyocyte can differentiate BMSCs significantly toward cardiomyocyte rather than co-culture alone.