Petr Gál

Efficacy of pregabalin in neuropathic pain in paediatric oncological patients

OBJECTIVE To evaluate the safety and efficacy of pregabalin in the management of chemotherapy-induced neuropathic pain in patients with childhood solid tumors and leukaemia. MATERIALS AND METHODS In an open-label study, 30 children (11 boys and 19 girls; mean age 13.5 years) who were treated for solid tumors and leukaemia, and developed a painful peripheral neuropathy, were medicated with pregabalin in the daily dose of 150-300 mg for 8 weeks. RESULTS Twenty-eight patients completed the 8-week follow-up. A significant and long-lasting pain relief was noted in 86% of these patients. Median VAS score decreased by 59% at the 8th week from baseline. Adverse effects were infrequent and transient. CONCLUSION The treatment with pregabalin resulted in a significant improvement in pain symptoms. The use of pregabalin in children is off-label so far. However, this drug seems to be a safe and effective remedy, which could significantly broaden the therapeutic spectrum in paediatric oncological patients suffering from neuropathic pain.

Allogeneic and autogenous transplantations of MSCs in treatment of the physeal bone bridge in rabbits

BackgroundThe aim of this experimental study on New Zealands white rabbits was to find differences in the results of treating the distal physeal femoral defect by the transplantation of autologous or allogeneic mesenchymal stem cells (MSCs). After the excision of a created bone bridge in the distal physis of the right femur, modified composite scaffold with MSCs was transplanted into the defect. In animal Group A (n = 11) autogenous MSCs were implanted; in animal Group B (n = 15) allogeneic MSCs were implanted. An iatrogenic physeal defect of the left femur of each animal not treated by MSCs transplantation served as control. The rabbits were euthanized four months after the transplantation. The treatment results were evaluated morphometrically (femoral length and valgus deformity measurement) and histologically (character and quality of the new cartilage).ResultsFour months after the transplantation, the right femurs of the animals in Group A were on average longer by 0.50 ± 0.04 cm (p = 0.018) than their left femurs, the right femurs of rabbits in Group B were on average longer by 0.43 ± 0.01 cm (p = 0.028) than their left femurs.4 months after the therapeutic transplantation of MSCs valgus deformity of the distal part of the right femur of animals in Group A was significantly lower (by 4.45 ± 1.86°) than that of their left femur (p = 0.028), in Group B as well (by 3.66 ± 0.95° than that of their left femur p = 0.001). However, no significant difference was found between rabbits with transplanted autogenous MSCs (Group A) and rabbits with transplanted allogeneic MSCs (Group B) either in the femur length (p = 0.495), or in its valgus deformity (p = 0.1597). After the MSCs transplantation the presence of a newly formed hyaline cartilage was demonstrated histologically in all the animals (both groups). The ability of transplanted MSCs to survive in the damaged physis was demonstrated in vivo by magnetic resonance, in vitro by Perls reaction and immunofluorescence.ConclusionThe transplantation of both autogenous and allogeneic MSCs into a defect of the growth plate appears as an effective method of surgical treatment of physeal cartilage injury. However, the Findings point to the conclusion that there is no clear difference in the final effect of the transplantation procedure used.

ChronOS Inject in Children with Benign Bone Lesions – Does It Increase the Healing Rate?

OBJECTIVE Benign bone lesions in children although rare, can result in a pathological fracture. Although their etiology and pathogenesis are not yet entirely clear, the phenomenon of spontaneous healing is well known. Nevertheless, some benign bone lesions are unlikely to heal spontaneously due to the patients age or high risk of fracture and deformity due to the lesions location or size. The following study presents our results after treatment of these bone cysts with chronOS Inject. METHODS From June 2004 to May 2007 23 patients with 24 benign bone cysts were treated with chronOS Inject, an injectable tricalcium phosphate, using a minimally invasive technique at two pediatric surgery departments. Postoperative follow-up examined bone healing, remodeling, chronOS Inject resorption and adverse effects. RESULTS 15 males and 9 females, mean age 11 years at time of diagnosis, were treated with chronOS Inject. The humerus was affected 13 times, the femur 7 times, the tibia twice and the radius, the fibula and talus once each. Except for one case, all pathological fractures healed within five weeks post-injection. Two children had cystic residues. No severe adverse effects were seen. CONCLUSIONS These preliminary results indicate that chronOS Inject could provide an alternative treatment for benign bone cysts that are unlikely to heal spontaneously due to the patients age, high risk of instability or pathological fracture due to the lesions size or location, or lesions that have already been treated several times using other methods without success.

Nanotechnology and mesenchymal stem cells with chondrocytes in prevention of partial growth plate arrest in pigs

INTRODUCTION This study describes the results achieved using a combination of allogeneic mesenchymal stem cells (MSCs) with chondrocytes (CHC) and a new scaffold consisting of type-I collagen and chitosan nanofibers in the prevention of partial growth plate arrest after iatrogenic injury in pigs. MATERIAL AND METHODS The miniature pig was selected as an experimental model to compare the results in the left femoral bones (MSCs and CHC in scaffold transplantation into the iatrogenic partial distal growth plate defect) and right femoral bones (scaffold alone transplantation). The experimental group consisted of 10 animals. Bone marrow from os ilium as the source of MSCs was used. A porous cylinder consisting of 0.5% by weight type-I collagen and 30% by weight chitosan, was the optimal choice. The length of the bone and angular deformity of distal femur after the healing period was measured and the quality and structure of the newly formed cartilage was histologically examined. RESULTS Transplantation of the composite scaffold in combination with MSCs and chondrocytes led to the prevention of growth disorder and angular deformity in the distal epiphysis of the left femur. Compared to the right (control) femur, tissue similar to hyaline cartilage with signs of columnar organization typical of the growth plate occurred in most cases. CONCLUSIONS The promising results of this study reveal the new and effective means for the prevention of bone bridge formation after growth plate injury.