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  Objective: Spinal cord injury (SCI) has become an especially challenging target in experimental neuroscience. Approach into the spinal cord is the interface among all different types of spinal cord injury modeling. The lower thoracic spinal cord has generated special interest due to the lower limbs’ spinal pattern generator position and presence of relative scales for behavioral assessment. However, a clear method with which to approach the thoracic spinal cord has yet to be determined.

  Methods : A total of 20 animals were subjected to this study. Following induction of anesthesia, the 10th thoracic vertebra were positioned, and muscles were retracted. Using the high speed rotary, the vertebral lamina were carefully thinned. As a final point, the reduced lamina was meticulously removed away to expose underlying spinal cord. Loco motor behavioral test (BBB) was implemented before and after surgery procedure.

  Results: This manuscript has presented the stepwise method to expose rat thoracic spinal cord. Whole procedure took less than an hour. Animals acquired complete BBB loco motor rating score before and after surgery indicating the safety of procedure.

  Conclusion: This article introduces simple and practical approach for the rat lower thoracic spine. The anatomical orientation, anesthesia , postoperative management , and common problems are discussed .

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Background & objectives: Pentavalent antimonials are the first-line drugs for treatment of leishmaniasis, which have multiple side effects such as drug toxicity. Moreover, parasite resistance to these drugs is rising around the world. Second-line drugs, including Amphotericin B and pantamidine have also side effects and expensive for patients. According to the cytotoxic effects of paraquat, this study was conducted to evaluate the effect of paraquat on Leishmania major promastigotes and HUVECs viability.
Methods: A number of 2.5×10⁶ of Leishmania major promastigotes were treated in each well of 96 well plates with different concentrations of paraquat. Cells were incubated for 48 hours in 24 °C. MTT test was performed for evaluating paraquat impact on promastigotes. The absorbance was measured using a microplate reader at 570 nm.  The trypan blue staining assay was performed to evaluate the number of viable Leishmania major promastigotes following paraquat treatment. Furthermore, the effect of paraquat concentrations on HUVECs viability was evaluated under the cell culture condition.
Results: The results of the MTT test showed that increasing concentrations of paraquat could significantly reduce the viability and the number of Leishmania major promastigotes in comparison to control group (p<0.05). In this study, the IC₅₀ for Leishmania major promastigotes was calculated as 272.46 µg/ml. Trypan blue results were in line with the finding of MTT assay. Moreover, we found that HUVECs were susceptible to paraquat (IC₅₀=188.99 µg/ml).
Conclusion: Paraquat has a strong inhibitory effect on Leishmania major promastigotes and human endothelial cells. Although more comprehensive studies on the effects of the topical use of paraquat on Leishmania major lesions in animal model and its side effects are necessary.