Anatomical variation of quadratus plantae in relation to flexor hallucis longus and flexor digitorum longus: a rare case.

The quadratus plantae (QP) is considered as a part of the plantar intrinsic foot muscles. This muscle has two lateral and medial heads of origin, both of which arise from the plantar surface of calcaneus, and insert into the tendon of flexor digitorum longus (FDL). Various functions have been attributed to the QP muscle, which includes assisting the plantar flexion of the lateral four toes, straightening the oblique pull of FDL and etc. Several anatomical variations of the QP muscle have been reported in the literature. During a routine dissection in the Department of Anatomy at Kerman University of Medical Sciences, a variant plantar muscle was observed in a 40-year-old male cadaver. In the present case, we report a rare variation associated with the insertion pattern of this muscle, which is reported for the first time in Iran. The tendinous end of the QP muscle was divided into three tendons and were then inserted to the inferior surface of 2nd, 3rd and 4th tendons of FDL. Also, a slim tendinous interconnection was also observed between the QP and flexor hallucis longus (FHL). The lack of connection between the FDL and FHL tendons was the other rare variation of this case. Exact knowledge of the possible variations of the QP muscle is of utmost importance to foot surgeons, clinicians and also anatomists.

Neural derivation of human dental pulp stem cells via neurosphere technique.

INTRODUCTION: Human dental pulp stem cells (hDPSCs) are multipotent stem cells providing an autologous noninvasive cell source. The study evaluates the neurogenic potential of hDPSCs using neural growth factor inducers and neurosphere technique. METHODS: The hDPSCs were differentiated into neurons using neural induction medium containing retinoic acid (RA). Neuroprogenitor cells were evaluated for nestin and NF68 using immunocytochemistry. The mature neuron markers, MAP­2 and ß-tubulin, were investigated at the end stage of induction phase. RESULTS: The neuroprogenitor differentiation was confirmed by immunostaining for nestin and NF68 markers. The differentiated neurons were positive for specific neuron markers, namely for MAP­2 and ß-tubulin. The results indicated that the neural differentiation medium and neurosphere technique improve the generation of neuroprogenitor cells as well as mature neurons via exhibiting specific neural markers, namely nestin, NF68, MAP­2 and ß-tubulin. CONCLUSION: Our findings highlight the differentiation capacity of hDPSCs via neurosphere technique in the presence of neural inducers for mesenchymal stem cells. It is suggested that the neural differentiation potential of hDPSCs can be exploited as a source of stem cells for therapy of neurodegenerative diseases (Fig. 5, Ref. 20).