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It is well known that some growth factors can not only rescue neurons from death, but also improve motor functions following spinal cord injury. However, their cellular distribution in situ and temporal expressions following spinal cord injury have not been determined, especially in primates. This study investigated the temporal changes in the expression of two growth factors--epidermal growth factor (EGF) and transforming growth factor-beta 1 (TGF-beta1) in the injured motoneurons of the spinal cord and the associated precentral gyrus in adult Rhesus monkeys subjected to spinal cord hemisection. Animals were allowed to survive 7, 14, 30 and 90 days post operation (dpo). Functional recovery of the hindlimbs was assessed using Tarlov scale. The immunohistological expressions of EGF and TGF-beta1 in the ventral horn motoneurons decreased sharply at 7 dpo in the cord segments caudal to the lesion site, which was followed by an increase and a peak between 14 and 30 dpo for EGF and at 90 dpo for TGF-beta1. Changes in the expression of EGF in the precentral gyrus were similar to that in the spinal cord. No TGF-beta1 immunoreactive neurons were detected in the precentral gyrus. In the spinal segments rostral to the lesion, the expressions of EGF and TGF-beta1 peaked at 30 dpo. The mRNA of EGF was detected in both spinal motoneurons and the precentral gyrus, while that of TGF-beta1, only in the spinal motoneuons, suggesting that the spinal motoneurons themselves could synthesize both the growth factors. Partial locomotor recovery in hindlimbs was seen, especially after 14 dpo. It was concluded that a possible association existed between the modulation of EGF and TGF-beta1 and the recovery of locomotor function, and their roles differed somewhat in the neuroplasticity observed after spinal cord injury in primates.

In the present study, we investigated the role of endogenous neurotrophin-3 in nerve terminal sprouting 2 months after spinal cord dorsal root rhizotomy. The left L 1-5 and L 7 -S 2 dorsal root ganglia in adult cats were exposed and removed, preserving the L 6 dorsal root ganglia. Neurotrophin-3 was mainly expressed in large neurons in the dorsal root ganglia and in some neurons in spinal lamina II. Two months after rhizotomy, the number of neurotrophin-3-positive neurons in the spared dorsal root ganglia and the density of neurite sprouts emerging from these ganglia were increased. Intraperitoneal injection of an antibody against neurotrophin-3 decreased the density of neurite sprouts. These findings suggest that endogenous neurotrophin-3 is involved in spinal cord plasticity and regeneration, and that it promotes axonal sprouting from the dorsal root ganglia after spinal cord dorsal root rhizotomy.

Neuroplasticity of the spinal cord following electroacupuncture (EA) has been demonstrated although little is known about the possible underlying mechanism. This study evaluated the effect of EA on expression of neurotrophins in the lamina II of the spinal cord, in cats subjected to dorsal rhizotomy. Cats received bilateral removal of L1-L5 and L7-S2 dorsal root ganglia (DRG, L6 DRG spared) and unilateral EA. They were sacrificed 7 days after surgery, and the L6 spinal segment removed and processed by immunohistochemistry and in situ hybridization histochemistry, to demonstrate the expression of neurotrophins. Significantly greater numbers of nerve growth factor (NGF) and neurotrophin-3 (NT-3) positive neurons, brain-derived neurotrophic factor (BDNF) immunoreactive varicosities and NT-3 positive neurons and glial cells were observed in lamina II on the acupunctured (left) side, compared to the non-acupunctured, contralateral side. Greater number of neurons expressing NGF mRNA was also observed on the acupunctured side. No signal for mRNA to BDNF and NT-3 was detected. The above findings demonstrate that EA can increase the expression of endogenous NGF at both the mRNA and protein level, and BDNF and NT-3 at the protein level. It is postulated that EA may promote the plasticity of the spinal cord by inducing increased expression of neurotrophins.

There are numerous studies reporting on the crucial roles of neurotrophins (NTFs) in neuronal survival and sprouting after spinal cord injury (SCI). But studies on endogenous changes of neurotrophins after SCI are few. In this study we explored by means of immunohistochemistry the localization of NGF, BDNF and NT-3 in the normal adult spinal cord (SC) and the changes in the expression of these chemicals in the ventral horn after right cord hemisection at T9-10. The results showed an obvious increase in the numbers of NGF, BDNF and NT-3-immunoreactive neurons in the ventral horn and also an increase in their intracellular optical density (O.D.) at 3, 7 and 21 days after cord hemisection, when compared with sham-operated rats. The expression of NGF peaked at 7 days postoperation (dpo), while BDNF and NT-3 expressions peaked at 3 dpo. Evaluation of hindlimb functions by Basso Beattie Bresnahan (BBB) scoring showed that the hindlimb support and stepping function improved very quickly at 7 dpo. This study indicated that NGF, BDNF and NT-3 could play important but different roles in the mechanisms of spinal neuroplasticity at different times after SCI.

To observe the efficacy and side effects of ivermectin in the treatment of intestinal nematode infections.A single dose of ivermectin 0.1, 0.2, 0.2 and 0.2 mg/kg was orally administered to cases with infection of Ascaris, hookworm, Trichuris and Enterobius respectively. A single dose of albendazole 400 mg was used as control.The egg negative conversion rates of ivermectin and albendazole were both 100% (34/34) for Ascaris infection, 17.6% (6/34) and 76.5% (26/34) respectively for hookworm infection, 67.6% (23/34) and 47.1% (16/34) respectively for Trichuris infection, 58.8% (20/34) and 100% (34/34) respectively for Enterobius infection. The worm discharge reached a peak in 1-2 days after treatment. The side effect of ivermectin was mild and transient showing no adverse effect on blood picture, liver function, renal function or ECG.Ivermectin shows similar effect on Ascaris with albendazole, better effect on Trichuris and poorer effect on hookworm and Enterobius than albendazole.