ABSTRACT
BACKGROUND: Neonatal hypoxic-ischemic (HI) injury has been considered to have acute and long term deleterious effects on many tissues, including the peripheral nerve. OBJECTIVES: In this study, the effects of a tumor necrosis factor-alpha (TNF-a) inhibitor (etanercept) on peripheral nerve damage and the ultrastructure of the sciatic nerve and gastrocnemius muscle in rats exposed to HI during the neonatal period were examined. MATERIAL AND METHODS: In this study, 45 seven-day-old rats were used and they were divided into three groups. The right carotid arteries of the rats in the saline and etanercept groups were ligated and put in a hypoxia chamber containing 8% oxygen for two hours. Just after hypoxia, the etanercept group was given 10 mg/kg etanercept, but the saline group had only saline intraperitoneally. The sham group rats' carotid arteries were not ligated or put in hypoxia. The amplitude, area and latency of sciatic nerve compound motor action potential (CMAP), which mainly reflects axonopathy and myelinopathy, were measured using standard techniques in the seventeenth week following the HI. Sciatic nerve and gastrocnemius muscle were evaluated with a transmission electron microscope, and grading for myelin sheath damage was done to all groups. RESULTS: Neuropathy was seen in rats after HI. While treatment with etanercept showed a protective effect for the axons of sciatic nerve, demyelination could not be recovered with etanercept. CONCLUSIONS: This study is the first in literature to show a partial interruption of the signal through the peripheral nerve fibers caused by axonal and myelin dysfunction continuation in rats exposed to HI after birth, in the 17th week.
ABSTRACT
Visceral leishmaniasis results in hematological problems such as cytopenias and coagulopathies. This disorder also has morphological effects on the bone marrow. Dyserythropoiesis is one of the most prominent seen with changes like multilobed nuclear cells and the appearance of bridges between nuclei and cytoplasms. Approximately half of the children with leishmaniasis showed dyserythropoietic findings in bone marrow aspirate slides. Because this in endemic regions, physicians of these countries must be alert to correctly diagnose disease and discriminate from other dyserythropoietic disorders.
ABSTRACT
AIMS: Perinatal hypoxic-ischemic insult has acute and long term deleterious effects on many organs including heart. Although tumor necrosis factor alpha (TNF-α) has been reported to increase soon after hypoxia, the inhibition of this mediator has not been documented. The aim of this study was to investigate the effects of a TNF-α inhibitor (etanercept) on contractility and ultrastructure of rat heart muscles exposed to hypoxia-ischemia during neonatal period. MAIN METHODS: Forty-five seven-day old rats divided into three groups were included in this study. The right carotid arteries of Saline and Etanercept groups of rats were ligated and kept in a hypoxia chamber containing 8% oxygen for 2h. Immediately after hypoxia, while Etanercept group was administered 10mg/kg etanercept, Saline group had only saline intraperitoneally. The carotid arteries of rats in Sham group were located without ligation and hypoxia. Mechanical activity of heart was recorded and tissue samples were examined by electron microscopy in the sixteenth week following the hypoxia-ischemia. KEY FINDINGS: While atrial contractile force in Etanercept group was similar to Sham group, there was significant decrease in Saline group (p<0.001). However, there was only non-significant decrease in ventricular contractility of Saline group comparing to Sham group (p>0.05). After hypoxia-ischemia, ultrastructural degenerative changes and mitochondrial damage in atriums of Etanercept group were significantly less severe than Saline group. SIGNIFICANCE: This study demonstrated that neonatal hypoxia-ischemia caused long term cardiac dysfunction and ultrastructural degenerative changes in the heart of rats. TNF-α inhibitor administration soon after hypoxia-ischemia may have heart protective effect.