Computed tomographic lymphangiography of the thoracic duct by subcutaneous iohexol injection into the metatarsal region.

OBJECTIVE: To evaluate the efficacy of subcutaneous iohexol injection into the metatarsal region for thoracic duct lymphangiography in dogs and to determine the minimum effective dose. STUDY DESIGN: Experimental study and clinical report. ANIMALS: Five healthy beagle dogs and one dog with chylothorax. METHODS: For the experimental study, iohexol was injected subcutaneously into the metatarsal region of five dogs at three doses (0.5, 0.75, and 1 mL/kg), and the injection sites were massaged gently. Computed tomography (CT) was performed 1, 3, 5, 7, 10, 15, and 20 minutes after iohexol injection. Subjective quality was assessed, and Hounsfield unit values were measured at several regions of interest (T1, T4, T8, T13, and L3). In the dog with chylothorax, iohexol (1.0 mL/kg) was injected into the right metatarsal region prior to CT. RESULTS: The thoracic duct was visualized and enhanced by contrast in all dogs after injection of 0.75 and 1.0 mL/kg of iohexol, and in two dogs after injection of 0.5 mL/kg at 3, 5, and 7 minutes. The thoracic duct was gradually attenuated with increasing doses of iohexol. In the dog with chylothorax, the entire thoracic duct was well enhanced and dilated, and tortuous cranial mediastinal lymphatics were detected. CONCLUSION: The thoracic duct was visualized when at least 0.75 mL/kg of iohexol was injected subcutaneously into the metatarsal region of dogs. CLINICAL SIGNIFICANCE: Subcutaneous injection of iohexol into the metatarsal region offers a simple alternative to conventional thoracic duct lymphangiography.

In-vitro Morphological Assessment of Apoptosis Induced by Nimbolide; A Limonoid from Azadirachta Indica (Neem Tree).

The present study was designed to investigate the in-vitro morphological assessment of apoptotic effect caused by nimbolide on the selected cancer cell lines (DU-145, PC-3, A-549) and normal cell lines (NIH3T3, CCD-18Co). The cells were grown in 6 well tissue culture plates after treatment with different concentrations of nimbolide and untreated control cells. Apoptotic and necrotic cells were measured using Hoechst 33342 and propidium iodide dual staining through a fluorescent microscope and also by staining with annexin V and propidium iodide through flow cytometric analysis. The activity of caspase 3, 8, and 9 was measured by caspases colorimetric assay kits. The number of apoptotic and necrotic cells were significantly higher in all selected cancer cell lines treated with nimbolide as compared with untreated control cells, whereas in normal cell lines no significant difference was observed between nimbolide treated and untreated cells. The activity of caspase 3, 8, and 9 was also significantly higher in all cancer cell lines treated with nimbolide as compared with untreated control cells while it did not change significantly in normal cell lines as compared with untreated control. The results of the present study suggested that nimbolide induced apoptosis only in cancer cells without affecting the normal cells and one of the apoptosis inducing mechanism is through the activation of caspases signaling pathways. Therefore, nimbolide may be a novel promising candidate as an anticancer drug in future.

In vitro comparative cytotoxic effect of Nimbolide: A limonoid from Azadirachta indica (Neem tree) on cancer cell lines and normal cell lines through MTT assay.

The present study was conducted to find the cytotoxicity in vitro of nimbolide, limonoids derivative of flowers and leaves from Azadirachta indica (neem tree) on the selected cell lines of cancer (Du-145, PC-3, A-549) and normal fibroblast cell lines (NIH3T3, CCD-18Co) using MTT assay. The cells were seeded in 96 multi-well tissue plate using different concentrations of nimbolide for 24hrs and 48hrs. The percentage of viability of cell lines was calculated by optical density obtained by micro plate reader and cytotoxic effect in term of IC50 value was determined by using linear regression analysis. The percentages of viability of cells treated with different concentrations of nimbolide were significantly lower (P<0.05) than the untreated cancer cell lines while in normal cell lines no significant difference (P>0.05) between treated and the non-treated cells was observed. Nimbolide exerted time and dose dependent cytotoxic effect on the cancer lines and mild effect on the normal cell lines. It was further confirmed through PKH 26. Results of the present study suggested nimbolide as a potent chemotherapeutic and chemopreventive agent as it exerted a more cytotoxic effect on cancer cell lines as compared with the normal cell lines. Nimbolide may be a new hope as an anticancer drug in future.

Effects of neural stem cells and 5-fluorocytosine in canine metastatic lung tumor.

This is the first case report to describe the tumor regressive effect of systemic human neural stem cell (NSC)/5-fluorocytosine (5-FC) therapy on canine metastatic lung tumor. The therapeutic effects appeared approximately two weeks after 5-FC administration. Thoracic radiographs revealed a reduced number of lung nodules and decreased nodule size. However, there were no significant antitumor effects on primary lesions in abdominal organs. In conclusion, human NSC/5-FC prodrug therapy can secure patient quality of life with the same or more therapeutic effects and fewer side effects than other recommended chemotherapies.

Evaluation of Bone Regeneration on Polyhydroxyethyl-polymethyl Methacrylate Membrane in a Rabbit Calvarial Defect Model.

This study was conducted to evaluate the capacity of guiding bone regeneration of polyhydroxyethyl-polymethyl methacrylate (PHEMA-PMMA) membrane as a guided tissue regeneration membrane for bone defects. Two 8-mm diameter transosseous round defects were made at the parietal bone of 18 New Zealand White rabbits. Defects were covered with or without PHEMA-PMMA membrane. Radiological and histological evaluation revealed that the bone tissue over the defect was more regenerated with time in both groups. However, there was significantly more bone regeneration at 8 weeks in the experimental group than the control group (p<0.05). There was no sign of membrane degradation or tissue inflammation and no invasion of muscle and fibrous tissue into defects. PHEMA-PMMA is a potential material for guided tissue regeneration membrane as it induces no adverse tissue reaction and effectively supports selective bone regeneration.

Evaluation of stability and biocompatibility of PHEMA-PMMA keratoprosthesis by penetrating keratoplasty in rabbits.

Artificial corneas have been developed as an alternative to natural donor tissue to replace damaged or diseased corneas. This study was conducted to evaluate the stability and biocompatibility of PHEMA-PMMA [poly (2-hydroxyl methacrylate)-poly (methyl methacrylate)] keratoprostheses in rabbits following penetrating keratoplasty. Sixteen male New Zealand White rabbits aged 16 weeks were divided into three groups. Group I and group II contained six rabbits each, while the control group had four rabbits. Experimental surgery was conducted under general anesthesia. The cornea was penetrated using an 8 mm diameter biopsy punch. In group I (core 5 mm & skirt 3 mm) and group II (core 6 mm & skirt 2 mm), the keratoprosthesis was placed into the recipient full thickness bed and sutured into position with double-layer continuous. In the control group, corneal transplantation using normal allogenic corneal tissue was performed with the same suture method. After four and eight weeks, keratoprosthesis devices were evaluated by histopathological analysis of gross lesions. Post-operative complications were observed, such as extrusion and infection in experimental groups. Most corneas were maintained in the defect site by double-layer continuous suture materials for 4 weeks and kept good light transmission. However, most artificial cornea were extruded before 8 weeks. Overall, combined PHEMA and PMMA appears to have sufficient advantages for production of artificial corneas because of its optical transparency, flexibility and other mechanical features. However, the stability and biocompatibility were not sufficient to enable application in humans and animals at the present time using penetrating keratoplasty. Further studies are essential to improve the stability and biocompatibility with or without other types of keratoplasty.

Traumatic and Non-traumatic Osteonecrosis in the Femoral Head of a Rabbit Model.

Osteonecrosis of the femoral head is an idiopathic, debilitating and progressive disease. A number of traumatic or non-traumatic animal models have been reported for research on osteonecrosis. This study was performed to compare the efficacy of femoral head osteonecrosis in rabbits by traumatic and non-traumatic methods. Twenty-seven New Zealand White rabbits were divided into three experimental groups, nine heads each. Two groups were surgically induced into osteonecrosis; a steel cerclage wire was ligated tightly around the neck of the right femoral head (Group W), and the femoral neck was tied with a cerclage wire in the same way as in the W group, and burned by attachment of an electrode tip to the wire and then the wire was removed (Group B). The other group was induced into osteonecrosis with a single intra-muscular injection of 20 mg/kg methyl-prednisolone acetate single injection (Group M). In the control group, the left femoral head of animals in group W and B was used. After two weeks, rabbits were sacrificed and the femoral head and neck were collected. Osteonecrosis of the femoral head was evaluated by radiography, histology and immunohistology methods. Osteonecrosis lesions in the femoral head were identified in traumatic models of groups W and B. Cartilage degeneration in the superficial layer and TUNEL positive cells in the femoral head were detected more in Group B than in Group W. These findings revealed that short-term induced osteonecrosis of the femoral head was effectively achieved by cautery around the femoral neck.