Dasatinib-induced Chylothorax in Chronic Myeloid Leukemia.

Dasatinib is a potent second-generation tyrosine kinase inhibitor (TKI) used in the first- and second-line treatment of chronic myeloid leukemia (CML). Chylothorax is a rare presentation that results in chyle leakage from the lymphatic system into the pleural space as a consequence of thoracic duct damage. Pleural effusion has been reported frequently in patients treated with Dasatinib however chylothorax has been rarely reported. Here we report an 18year old female presenting with chylothorax after 63 months of Dasatinib intake along with a review of the relevant literature. Currently there are no standard guidelines regarding the approach to chylothorax management after the initial discontinuation of Dasatinib. Since the TKI options after stopping Dasatinib are limited, and most patients would have already failed the trial of first generation TKI, we suggest implementing a complete treatment strategy for this patient population. Key words: chronic myeloid leukemia, Dasatinib, Pleural effusion, Chylothorax.

Monoamine oxidase-B inhibitor protects degenerating spinal neurons, enhances nerve regeneration and functional recovery in sciatic nerve crush injury model.

Monoamine oxidase-B (MAOB), a flavin adenine dinucleotide (FAD), is an enzyme which catalyzes the oxidation of amines. MAOB is proposed to play a major role in the pathogenesis of neurodegeneration through the production of reactive oxygen species (ROS) and neurotoxins. The present study was designed to outline the effects of the MAOB inhibitor (MAOB-I) on neuroprotection of spinal neurons, regeneration of sciatic nerve fibers, and recovery of sensory-motor functions in the sciatic nerve crush injury model. Male Wistar rats (4-months-old) were assigned to i) Naïve (N), ii) Sham (S), iii) Sciatic nerve crush and treated with saline (CRUSH + SALINE) and iv) Sciatic nerve crush and treated with MAOB inhibitor (CRUSH + MAOB-I) groups (n = 10/group). In groups iii and iv, the crush injury was produced by crushing the sciatic nerve followed by treatment with saline or MAOB-I (Selegiline® 2.5 mg/kg) intraperitoneally for 10 days. Behavioral tests were conducted from week 1 to week 6. At the end of the study, sciatic nerve and lumbar spinal cord were examined by immunohistochemistry, light and electron microscopy. MAOB-I treatment showed significant improvement in sensory and motor functions compared to saline treatment (p < 0.05-0.001) in injured nerves. The morphological study showed a significantly increased number of nerve fibers in sciatic nerve distal to the site of injury (p < 0.05), with better myelination pattern in CRUSH + MAOB-I treated group compared to CRUSH + SALINE group. Spinal cord ventral horns showed a significant increase in the number of NeuN-immunoreactive neurons in the MAOB-I treated group compared to Saline treated group (p < 0.01). MAOB-I has a significant potential for protecting the degenerating spinal cord neurons and enhancing the regeneration of injured sciatic nerve fibers following crush injury.