Effects of the different administration frequencies of teriparatide (PTH [1-34]) on new bone formation of expanded midpalatal sutures in rats: A histomorphometric and micro-computed tomography analysis.

OBJECTIVE: The aim of the study was to evaluate the effect of 4 µg/kg teriparatide administered at intermittent and continuous frequencies on bone formation in the expanded midpalatal suture region using histomorphometric and micro-computed tomography (micro-Ct) analysis. Settings and sample population: In this study, 24 Sprague Dawley male rats were used. METHODS: The experimental animals were divided into 3 groups as follows: Group 1: only maxillary expansion, Group 2: maxillary expansion with continuous teriparatide administration (2 µg in the morning and 2 µg in the evening) and Group 3: maxillary expansion with intermittent teriparatide administration (daily 4 µg/kg). The expansion appliance was fixed to maxillary incisors of all animals within the 5-day expansion period, followed by a 12-day retention phase. Animals were sacrificed at the end of the retention period, and specimens were evaluated by micro-Ct and histomorphometric analysis respectively. RESULTS: The results of the histomorphometric analysis showed that Group 3 had the highest number of osteoblasts (1042 ± 90.76) (P < .01). In addition, the results of micro-Ct analysis revealed that Group 3 had the highest bone volume/total volume (16% ± 0), bone mineral density (173.82 ± 2.6 mgHA/cm3 ) and least midpalatal suture width (0.13 ± 0.001 mm) (P < .01). Osteoblasts number and micro-Ct analysis values of Group 2 were higher than those of Group 1 but no significant differences between them (P > .01). CONCLUSION: Intermittently administered TP (4 µg/kg once a day) was seen to enhance bone formation and mineralization. In the future, it can be used in drug studies that will increase or stimulate bone formation as well as in the midpalatal suture area.

The structure of spleen in the long-legged buzzard (Buteo rufinus): Histological and immunohistochemical study.

The aim of this study was to examine the structure of the spleen in the long-legged buzzard (Buteo rufinus) by histologically and the distribution of the catalase in the spleen by immunohistochemically. The tissue materials were taken from three healthy long-legged buzzards provided by permission of the General Directorate of Nature Protection and National Parks (Ankara, Turkey). The long-legged buzzard spleen is surrounded by smooth muscle cells and fibrous connective tissue. In addition, trabecular structures are not found in the capsule. The separation of white and red pulp areas could not be precisely determined. Plasma cells were detected especially around the lymphoid follicles and lymphatic follicles and Schweigger-Seidel cells were formed by reticulum strands. Alcian blue positive reaction was determined in Schweigger-Seidel cells and endothelial cells of the long-legged buzzard spleen. The intense cytoplasmic catalase immunoreactivity was observed in the Schweigger-Seidel cells and nuclear in some red pulp cells of the long-legged buzzard spleen. Consequently, determination of the histological structure and catalase immunoreactivity of the spleen on the long-legged buzzard by this study could be support for the future researches.