Graphene-MoS2 polyfunctional hybrid hydrogels for the healing of transected Achilles tendon.

Healing of injured tendon is a major clinical challenge in orthopaedic medicine, due to the poor regenerative potential of this tissue. Two-dimensional nanomaterials, as versatile scaffolds, have shown a great potential to support, trigger and accelerate the tendon regeneration. However, weak mechanical properties, poor functionality and low biocompatibility of these scaffolds as well as post-surgery infections are main drawbacks that limit their development in the higher clinical phases. In this work, a series of hydrogels consisting polyglycerol functionalized reduced graphene oxide (PG), polyglycerol-functionalized molybdenum disulfide (PMoS2) and PG/PMoS2 hybrid within the gelatin matrix are formulated in new scaffolds and their ability for the healing of injured Achilles tendon, due to their high mechanical properties, low toxicity, cell proliferation enhancement, and antibacterial activities is investigated. While scaffolds containing PG and PMoS2 showed a moderate tendon regeneration and anti-inflammatory effect, respectively, their hybridization into PG/PMoS2 demonstrated a synergistic healing efficiency. Along the same line, an accelerated return of tendon function with low peritendinous adhesion and low cross-sectional area in animal group treated with scaffold containing PG/PMoS2 was observed. Taking advantage of the high biocompatibility, high strength, straightforward construction and fast tendon regeneration, PG/PMoS2 can be used as a new scaffold for the future tissue engineering.

The effect of aqueous extract of Prunus dulcis on tibial bone healing in the rabbit.

BACKGROUND: Bone fractures are medical emergencies that require prompt intervention to help return bone to its normal function. Various methods and treatments have been utilized to increase the speed and efficiency of bone repair. This study aimed to investigate the treatment effects of Prunus dulcis aqueous extract on tibial bone healing in rabbits. METHODS: All animals were distributed in five groups with six rats in each group, including the sham group, the control group in which tibial lesion was made and received distilled water, treatment groups with 150 mg kg-1, 300 mg kg-1 doses of Prunus dulcis extract, and osteocare treated group. Biochemical blood factors including calcium, phosphorus, and alkaline phosphatase (on days 0, 10, 30, and 50), biomarkers of oxidative stress such as GPx, CAT, and MDA (on days 10 and 30), radiological evaluation, histopathological parameters, and osteocalcin immunohistochemical expression were assessed. RESULTS: The data showed calcium levels in the treatment groups increased significantly from day 10 to day 50, respectively, and blood phosphorus levels decreased from day 10 to day 50 in the treatment groups. Alkaline phosphatase initially increased and then decreased in treatment groups. In the treatment groups, GPx and CAT levels significantly increased, and the serum amount of MDA reduced. The best antioxidant results were related to the extract-treated group with a higher dose. Radiographic score was significantly higher in the treatment groups than the control group on day 30. Based on the pathological findings, the healing occurred faster in the extract-treated group with a higher dose. Osteocalcin expression was significantly higher in the control group than that in the treatment groups. CONCLUSIONS: Treatment with Prunus dulcis extract with a dosage of 300 mg/kg accelerated tibial bone healing in rabbits.

Metastatic giant cell osteosarcoma in a cat.

A four-year-old male Persian cat was referred with three weeks history of progressive lameness due to a rigid osseous mass with 3.50×2.50×2.00 cm in dimensions in his left arm. In the histopathological evaluation of bone biopsy, two distinct populations of cells including multinucleated giant cells and oval cells which embedded in a fibro-osseous stroma and surrounded by lamellar bone trabeculae were observed. At necropsy, multiple metastatic nodules with different sizes unveiled in the liver and spleen. Microscopically, those tumor cells which already described in the bone lesion were also infiltrated to the liver and spleen. The neoplastic cells had no immunoreaction to CD68, desmin, alpha smooth muscle actin, S100, CD20, CD3 and pancytokeratin, but only a few cells had reaction to vimentin were similar to fibroblasts.

Cerebral astrocytoma in a sheep.

Astrocytoma as one of the most common central nervous system (CNS) tumors is rarely reported in veterinary literature. A 7-year-old Persian Lori-Bakhtiari ewe was presented to the clinic with a two months history of progressive blindness, nystagmus to the right, bilaterally decreased pupillary reflexes, head pressing and paddling. At necropsy, a whitish well-circumscribed mass with dimensions of 3.50×2.50×1.50 cm was observed in the dorsal parietal lobe of the left cerebral hemisphere. Microscopically, the mass was well-circumscribed and highly cellular, consisted of round to elongated cells with scant and vacuolated cytoplasm with few, flaccid processes. The nuclei were round to oval with densely stippled chromatin and indistinct nucleoli. Immunohistochemical analyses showed positive staining for vimentin, S100 and glial fibrillary acidic protein. Definitive diagnosis of cerebral protoplasmic astrocytoma was made on the basis of the histopathological and immunohistochemical findings. This type of neoplasm should be included in the differential diagnosis of CNS lesions in the sheep.

Leydig cell tumor in ovary of a German Shepherd bitch: An immunohistopathological study.

Leydig cell tumor as a sex-cord stromal tumor is a relatively uncommon ovarian tumor in bitch. A 10-year-old female German Shepherd dog was presented because of protrusion of a large tumor-like mass of 16 × 14 × 7 cm in dimensions from her vagina. After stabilization of the patient, the mass was removed surgically and concurrent ovariohysterectomy was also performed. Macroscopically, the healthy tissue of the right ovary was totally replaced by a homogeneous, brown and firm mass. The neoplasm was well-circumscribed and nodular and it was clearly demarcated from the healthy tissue. Histological examination revealed the presence of solid sheets and acinar structures composed of polyhedral to elongated cells. The neoplastic cells had large, eosinophilic, and vacuolated cytoplasms with round to oval nuclei and expressed vimentin on immunohistochemical examination. These gross, microscopic and immuno-histochemical features are characteristics of ovarian Leydig cell tumor.