The enhanced photocatalytic performance of SnS2@MoS2 QDs with highly-efficient charge transfer and visible light utilization for selective reduction of mythlen-blue.

Molybdenum disulfide (MoS2) has recently been considered as an effective material for potential photocatalytic applications; however, its photocatalytic activity was limited due to the low density of active sites. In this work, MoS2 Quantum dots (QDs) were synthesized via the ultrasonication technique to construct heterostructure with SnS2 nanosheets (SnS2@MoS2 QDs) and the prepared materials were tested for photocatalytic applications for Methylene blue (MB). Pristine SnS2 and SnS2@MoS2 QDs nanocomposite were analyzed by XRD, TEM, PL, and Uv-Vis. Both SnS2 and SnS2@MoS2 QDs exhibited a single trigonal phase with the P-3m1 space group. The TEM analysis confirmed the coupling between the pristine SnS2 and SnS2@MoS2 QDs. The results of photocatalytic activity toward MB indicated that SnS2@MoS2 QDs material exhibits much superior photocatalytic performance compared to pristine SnS2. The excellent photodegradation performance of SnS2@MoS2 QDs is due in the main to the formation of heterojunction between SnS2 and MoS2 QDs with narrow bandgap formation, which results in a facile carriers transfer and thus high photocatalytic efficiency. A representative mechanism of the photodegradation for SnS2@MoS2 QDs photocatalyst was proposed. Such an ultrasonic technique is capable of producing small metallic particle size that can be used to construct new heterostructures for water remediation applications.

Gingival mesenchymal stem cells as an alternative source to bone marrow mesenchymal stem cells in regeneration of bone defects: In vivo study.

Healing of critical sized bone defects represents a challenging issue in clinical and research fields. Current therapeutic techniques, such as bone grafts or bone grafts substitutes, still have limitations and drawbacks. Therefore, stem cell-based therapy provides a prospective approach to enhance bone regeneration. The present study aimed to assess the regenerative capacity of Gingival mesenchymal stem cells (GMSCs) as well as Bone marrow mesenchymal stem cells (BMSCs) loaded on NanoBone scaffold, in comparison to the unloaded one, in surgically created bone defects in rabbits' tibiae. To achieve this aim, critical sized bone defects, of 6-mm diameter each, were unilaterally created in tibiae of adult New Zeeland male white rabbits (n = 27). The rabbits were then divided randomly into three groups (9 each) and received the following: Group I: Unloaded NanoBone Scaffold, Group II: GMSCs Loaded on NanoBone Scaffold, and Group III: BMSCs Loaded on NanoBone Scaffold. Three rabbits from each group were then sacrificed at each time point (2, 4 and 6 weeks postoperatively), tibiae were dissected out to evaluate bone healing in the created bony defects; both histologically and histomorphometrically. The findings of this study indicate that both GMSCs and BMSCs exhibited fibroblast morphology and expressed phenotypic MSCs markers. Histologically, local application of GMSCs and BMSCs loaded on NanoBone scaffold showed enhanced the pattern of bone regeneration as compared to the unloaded scaffold. Histomorphometrically, there was astatistically insignificant difference in the new bone area % between the bony defects treated with GMSCs and BMSCs. Thus, GMSCs can be considered as a comparable alternative source to BMSCs in bone regeneration.

The role of exogenous epidermal growth factor on Ki-67 proliferation marker expression in the submandibular salivary gland of albino rats receiving doxorubicin.

Background: This study was conducted to evaluate the role of exogenous epidermal growth factor (EGF) injection on the Ki-67 immuno-expression in submandibular salivary gland tissue of rats receiving doxorubicin (DXR). Methods: A total of 21 two-month-old male albino rats, of 200 g body weight, were divided into three groups: control group; DXR group, the rats received 20 mg/kg body weight DXR as a single intra peritoneal injection; DXR+EGF group, the rats received the same dose of DXR and on the next day they were injected intraperitoneally with 10 µg/kg body weight of EGF daily for one week. Histological sections and immunohistochemical expression of Ki67 sections were examined using a ZEISS Primo Star light microscopy and images taken using Tucsen IS 1000 10.0MP Camera. Results: Ki-67 expression was significantly increased in submandibular salivary glands of rats after DXR injection. However, Ki-67 expression in the glandular tissue was restored to normal levels after EGF injection. Conclusions: EGF preserved glandular architecture after DXR injection and maintained Ki-67 immune-expression within the glandular tissue near to the normal level.