OBJECTIVE: To evaluate the effects of interleukin-6 (IL-6) and erythropoietin (EPO) in experimental acute spinal cord injury (SCI) in rats. METHODS: Using standardized equipment, namely, a New York University (NYU) Impactor, a SCI was produced in 50 Wistar rats using a 10-g weight drop from a 12.5-mm height. The rats were divided into the following 5 groups of 10 animals each: “Group EPO”, treated with erythropoietin only; “Group EPO + IL-6”, treated with both substances; “Group IL-6”, receiving IL-6 administration only; “Group Placebo”, receiving a placebo solution; and “Group Sham”, submitted to an incomplete procedure (only laminectomy, without SCI). All drugs and the placebo solution were administered intraperitoneally for three weeks. The animals were followed up for 42 days. Functional motor recovery was monitored by the Basso, Beattie, and Bresnahan (BBB) scale on days 2, 7, 14, 21, 28, 35 and 42. Motor-evoked potential tests were performed on the 42nd day. Histological analysis was performed after euthanasia. RESULTS: The group receiving EPO exhibited superior functional motor results on the BBB scale. IL-6 administration alone was not superior to the placebo treatment, and the IL-6 combination with EPO yielded worse results than did EPO alone. CONCLUSIONS: Using EPO after acute SCI in rats yielded benefits in functional recovery. The combination of EPO and IL-6 showed benefits, but with inferior results compared to those of isolated EPO; moreover, isolated use of IL-6 resulted in no benefit.

RESUMO Objetivos Diversos casos de sinovite vilonodular pigmentada difusa bilateral (SVNP) ou tumor de células gigantes tenossinoviais foram descritos na literatura. Entretanto, algumas apresentações são raras e o diagnóstico diferencial é necessário. Métodos O objetivo do estudo foi realizar uma revisão da literatura relacionada à SVNP e relatar uma apresentação de forma bilateral e localizada rara na região supra-patelar. Foi realizada uma revisão dos bancos de dados do Pubmed Clinical Queries, MeSH e unitermos relacionados com SVNP e tumor de células gigantes tenossinoviais. Resultados Dois casos de SVNP bilateral e local foram descritos anteriormente. No entanto, nenhum deles foi localizado no compartimento supra-patelar. Até onde sabemos, este relato é o primeiro caso descrito de SVNP bilateral localizada supra-patelar. Apresentamos uma mulher de 28 anos com SVNP bilateral no recesso supra-patelar do joelho. A RM mostrou baixo sinal dos nódulos nas imagens ponderadas em T1 e T2, associados ao pigmento hemossiderina. Conclusão O achado mais importante está relacionado à raridade e localização. A histopatologia confirmou um caso raro de pigmento de hemossiderina no nódulo da cápsula com conteúdo viloso não pigmentado internamente. O diagnóstico diferencial com lipoma arborescens na forma supra-patelar é necessário devido à localização comum. Nível de Evidência IV; Série de casos.

ABSTRACT Objectives Several cases of bilateral diffuse pigmented villonodular synovitis (PVNS) or tenosynovial giant cell tumor have been described in the literature. Nevertheless, some presentations are rare and differential diagnoses are necessary. Methods The purpose of this study was to perform a systematic review of the literature related to PVNS and to report a rare supra-patellar bilateral and focal presentation. We performed a systematic data review in the Pubmed Clinical Queries database using MeSH and keywords related to PVNS and tenosynovial giant cell tumor. Results Two cases of bilateral and local PVNS had been previously described, but neither was localized in the supra-patellar compartment. To our knowledge, this case report is the first to describe supra-patellar bilateral and localized PVNS of the knee. This case involves a 28 -year-old woman with bilateral localized PVNS of the supra-patellar recess of the knee. MRI showed a low-signal intensity nodule in T1- and T2-weighted images. These were associated with hemosiderin pigmentation. Conclusion The most important finding of the case reported is related to rarity and location. Histopathology analysis confirmed a rare case of hemosiderin pigmentation in the capsular nodule with internal non-pigmented villous content. Lipoma arborescens in the supra-patellar form must be ruled out as a differential diagnosis since it occurs in the same site. Level of Evidence IV; Case series.

OBJECTIVE: To standardize a spinal cord lesion mouse model. METHODS: Thirty BALB/c mice were divided into five groups: four experimental groups and one control group (sham). The experimental groups were subjected to spinal cord lesion by a weight drop from different heights after laminectomy whereas the sham group only underwent laminectomy. Mice were observed for six weeks, and functional behavior scales were applied. The mice were then euthanized, and histological investigations were performed to confirm and score spinal cord lesion. The findings were evaluated to prove whether the method of administering spinal cord lesion was effective and different among the groups. Additionally, we correlated the results of the functional scales with the results from the histology evaluations to identify which scale is more reliable. RESULTS: One mouse presented autophagia, and six mice died during the experiment. Because four of the mice that died were in Group 5, Group 5 was excluded from the study. All the functional scales assessed proved to be significantly different from each other, and mice presented functional evolution during the experiment. Spinal cord lesion was confirmed by histology, and the results showed a high correlation between the Basso, Beattie, Bresnahan Locomotor Rating Scale and the Basso Mouse Scale. The mouse function scale showed a moderate to high correlation with the histological findings, and the horizontal ladder test had a high correlation with neurologic degeneration but no correlation with the other histological parameters evaluated. CONCLUSION: This spinal cord lesion mouse model proved to be effective and reliable with exception of lesions caused by a 10-g drop from 50 mm, which resulted in unacceptable mortality. The Basso, Beattie, Bresnahan Locomotor Rating Scale and Basso Mouse Scale are the most reliable functional assessments, and but the horizontal ladder test is not recommended.

OBJECTIVES: To compare bioactive glass and autograft regarding their histomorphometric characteristics. METHODS: The authors conducted a prospective case-control experimental study on animals in order to compare the histomorphometric characteristics of bioactive glass versus autograft. Eight rabbits underwent surgery in which a cavitary defect was created in both proximal femurs. One side was filled with bioactive glass granules and the other, with autograft grafted from the contralateral side. The sides were randomized. Fourteen days after surgery, the animals were euthanized. RESULTS: Histologic analysis revealed that bone neoformation was equivalent among the two groups and the osteoblasts cell-count was higher in the femurs treated with bioactive glass. The osteocytes cell-count, however, was lower. The similarity in bone formation between both groups was consistent to literature findings. CONCLUSION: Bioactive glass is similar to autograft regarding bone neoformation in this animal model of cavitary bone defects. Level of Evidence III, Case-Control Study.

Ceratoacantoma geralmente ocorre na pele e raramente é encontrado na conjuntiva. Relatamos um caso de uma mulher de 34 anos que apresentou uma massa conjuntival de rápido crescimento. O tumor foi retirado com margem de segurança para excluir carcinoma de células escamosas. Ao exame histopatológico, o tumor apresentou configuração crateriforme, sendo consistente com ceratoacantoma atípico. Não houve recorrência após dois anos de seguimento. Ceratoacantoma conjuntival é uma doença rara. Um diagnóstico diferencial entre carcinoma de células escamosas e ceratoacantoma pode ser difícil. Recomendamos total remoção e seguimento cuidadoso de pacientes com lesões escamosas crateriformes.

Keratoacanthoma generally occurs on the skin; it is rarely found in the conjunctiva. A case of a 34-year-old woman with a rapidly growing conjunctival mass is reported. The tumor was excised with a safety margin to exclude squamous cell carcinoma. Histopathologically it was crateriform and consistent with atypical keratoacanthoma. There has been no recurrence in 2 years of follow-up. Conjunctival keratoacanthoma is rare; differential diagnosis of conventional squamous cell carcinoma and keratoacanthoma can be difficult. We recommend complete surgical excision and careful follow-up of crateriform squamous proliferations.