Luciano Miller Reis Rodrigues

Liver Necrosis Induced by Acute Intraperitoneal Ethanol Administration in Aged Rats

It is generally agreed that the deleterious pathophysiological effects of ethanol are caused, at least partially by an increase in free radical production. However, little attention has been directed to the effects of ethanol upon elderly organisms. Male Wistar rats at ages 3, 6, 12, 18 and 24 months were treated either with a single i.p. dose of 35% ethanol (v/v) at 3 g ethanol/kg body weight or an isovolumetric amount of 0.9% saline solution. We then assessed the plasma levels of transaminases and hepatic levels of oxidative stress-related parameters, followed by liver histological evaluation. The younger rats (3 months old) were not affected by the treatment with ethanol with respect to any of the studied parameters except for a lowering of total hepatic GSH and an increase in hepatic thiobarbituric acid reactants (TBARS) formation, while animals older than 3 months were increasingly more affected by the treatment. Acute ethanol treatment elicited the similar responses to those in the 3 months-old group, plus a decrease in the hepatic and plasma levels of g -carotene and the plasma level of f -tocopherol, as well as an increase in the activity of plasma transaminases. In the 12, 18 and 24 months old groups, there was increasing liver necrosis. These findings suggest that liver damage induced by acute ethanol administration in elderly rats may involve a lack of antioxidants.

Heparanase isoform expression and extracellular matrix remodeling in intervertebral disc degenerative disease

OBJECTIVE: To determine the molecules involved in extracellular matrix remodeling and to identify and quantify heparanase isoforms present in herniated and degenerative discs. INTRODUCTION: Heparanase is an endo-beta-glucuronidase that specifically acts upon the heparan sulfate chains of proteoglycans. However, heparanase expression in degenerative intervertebral discs has not yet been evaluated. Notably, previous studies demonstrated a correlation between changes in the heparan sulfate proteoglycan pattern and the degenerative process associated with intervertebral discs. METHODS: Twenty-nine samples of intervertebral degenerative discs, 23 samples of herniated discs and 12 samples of non-degenerative discs were analyzed. The expression of both heparanase isoforms (heparanase-1 and heparanase-2) was evaluated using immunohistochemistry and real-time RT-PCR analysis. RESULTS: Heparanase-1 and heparanase-2 expression levels were significantly higher in the herniated and degenerative discs in comparison to the control tissues, suggesting a possible role of these proteins in the intervertebral degenerative process. CONCLUSION: The overexpression of heparanase isoforms in the degenerative intervertebral discs and the herniated discs suggests a potential role of both proteins in the mediation of inflammatory processes and in extracellular matrix remodeling. The heparanase-2 isoform may be involved in normal metabolic processes, as evidenced by its higher expression in the control intervertebral discs relative to the expression of heparanase-1.

Estudo prospectivo de avaliação de dor e incapacidade de pacientes operados de estenose de canal lombar com seguimento mínimo de dois anos

OBJETIVO: realizar uma analise prospectiva de dor e incapacidade em pacientes operados de estenose de canal lombar apos dois anos do procedimento atraves da escala VAS e Roland Morris. METODOS: trinta e oito pacientes foram avaliados por meio dos questionarios em um momento pre-operatorio, pos-operatorio um mes, seis meses, um ano e dois anos, tendo sido realizada descompressao e artrodese com instrumentacao pedicular associada. RESULTADOS: foi observado melhora nas analises comparativas de dor e incapacidade no decorrer do seguimento em relacao aos valores iniciais, porem uma tendencia a estabilizacao do quadro com sua evolucao. CONCLUSAO: o tratamento cirurgico da estenose do canal lombar, quando criteriosamente indicado, melhora a dor e a incapacidade apos dois anos de seguimento.

Content of liver and brain ubiquinol-9 and ubiquinol-10 after chronic ethanol intake in rats subjected to two levels of dietary α-tocopherol.

To assess the effect of chronic ethanol ingestion in the content of the reduced forms of coenzymes Q9 (ubiquinol-9) and Q10 (ubiquinol-10) as a factor contributing to oxidative stress in liver and brain, male Wistar rats were fed ad libitum a basal diet containing either 10 or 2.5 mg α-tocopherol/100 g diet (controls), or the same basal diet plus a 32% ethanol-25% sucrose solution. After three months treatment, ethanol chronically-treated rats showed identical growth rates to the isocalorically pair-fed controls, irrespectively of α-tocopherol dietary level. Lowering dietary α-tocopherol led to a decreased content of this vitamin in the liver and brain of control rats, without changes in that of ubiquinol-9, and increased levels of hepatic ubiquinol-10 and total glutathione (tGSH), accompanied by a decrease in brain tGSH. At the two levels of dietary α-tocopherol, ethanol treatment significantly decreased the content of hepatic α-tocopherol and ubiquinols 9 and 10. This effect was significantly greater at 10 mg α-tocopherol/100 g diet than at 2.5, whereas those of tGSH were significantly elevated by 43% and 9%, respectively. Chronic ethanol intake did not alter the content of brain α-tocopherol and tGSH, whereas those of ubiquinol-9 were significantly lowered by 20% and 14% in rats subjected to 10 and 2.5 mg α-tocopherol/100 g diet, respectively. It is concluded that chronic ethanol intake at two levels of dietary α-tocopherol induces a depletion of hepatic α-tocopherol and ubiquinols 9 and 10, thus contributing to ethanol-induced oxidative stress in the liver tissue. This effect of ethanol is dependent upon the dietary level of α-tocopherol, involves a compensatory enhancement in hepatic tGSH availability, and is not observed in the brain tissue, probably due to its limited capacity for ethanol biotransformation and glutathione synthesis.

Vertebrectomy of giant cell tumor with vertebral artery embolization: case report.

Giant cell tumors (GCT) are rare in the cervical spine in adolescent children. This tumor is histologically benign, but there is a high recurrence rate. Although surgical resection of GCT arising in the cervical spine is commonly regarded as recommended treatment method, it is still a challenge to achieve satisfactory results. The authors describe a case of a patient of adolescent age with a GCT in the cervical spine. It was necessary to study the embolization of the vertebral artery to planning the vertebrectomy surgery for resection of the entire tumor to avoid recurrence. The resection of the tumor was carried out by combined access (anteriorly and posteriorly) and was stabilized with plate, posterior lateral mass screws, and autologous iliac crest graft.

Association Between the FokI and ApaI Polymorphisms in the Vitamin D Receptor Gene and Intervertebral Disc Degeneration: A Systematic Review and Meta-Analysis

BACKGROUND Evidence supporting an association of intervertebral disc degeneration (DD) with polymorphisms of the vitamin D receptor (VDR) gene has been controversial. We performed a meta-analysis of these studies to determine if there was substantial evidence to support such an association between the VDR polymorphisms and DD. METHODS PubMed, Embase, and Science Direct databases were searched for studies that investigated associations of the FokI (rs2228570, rs10735810), and ApaI (rs7975253) polymorphisms of the VDR gene with DD. From the extracted genotype data from 14 publications, we estimated risk (odds ratio [OR] with 95% confidence intervals). RESULTS Overall associations of FokI with DD were absent (OR 0.96-1.04, p = 0.73-0.95) with heterogeneity in the dominant and codominant models (pheteroegeneity <0.10, I2 = 47-57%). Post-outlier pooled effects yielded dominant significance indicating reduced risk (OR 0.77, p = 0.01) with concomitant zero heterogeneity (I2 = 0%). ApaI effects pointed to reduced risks, with overall dominant significance (OR 0.69, p = 0.04) and Asian subgroup nonsignificance (OR 0.75-0.93, p = 0.17-0.74). In FokI, Non-Hispanic Caucasians (OR 0.77, p = 0.01) and males (OR 0.36-0.66, p = 0.001-0.04) were protected but not Hispanic Caucasians (OR 1.39-1.85, p = 0.006-0.05) and females (OR 1.72, p = 0.05). Tests of interaction between the genders highlighted female susceptibility and male protection (p = 0.001-0.005). Zero heterogeneity (I2 = 0%) is a key strength of these significant effects. CONCLUSION This meta-analysis confirmed the protective role of the ApaI polymorphism, however, susceptibility and protective effects of the FokI polymorphism may be ethnic and gender specific.

Remodelamento da matriz extracelular em degeneração experimental do disco intervertebral

OBJECTIVE: To evaluate the remodeling of the extracellular matrix in intervertebral disc degeneration through the experimental model of intervertebral disc degeneration. METHODS: The model of disc degeneration induction, using needle 20G and 360° rotation, was applied for 30 seconds between the 6th/7th, and 8th/9th coccygeal vertebrae of Wistar rats. The intermediary level, between the 7th and 8th vertebrae, was taken as control, not being subjected puncture. The distribution of the extracellular matrix components involved in the remodeling and inflammation process, such as proteoglycans (aggrecan, decorin, biglycan), growth factors (TGFβ), heparanase isoforms (HPSE1, HPSE2), metaloprotesasis-9 (MMP9) and interleukins (IL-6, IL-10) was analyzed during the post-injury period (15 to 30 days) and in the control group (discs collected immediately after the puncture, day zero). On the 15th day, acute phase of the disease, a reduced expression of extracellular matrix components had been observed, whilst there were no differences in the interleukins expression. At 30 days, the molecules followed a very similar pattern of expression in the control group (not affected by disc degeneration). RESULTS: The results show that during the acute phase significant alterations in the extracellular matrix components occur and in the late phase intervertebral disc returns to a profile similar to noninvolved tissue, probably due to extensive remodeling process of the extracellular matrix that is capable of regenerating the damaged tissue. CONCLUSION : The experimental model used demonstrated the occurrence of significant changes in the extracellular matrix during the period analyzed after induction of intervertebral disc degeneration. Laboratory investigation.OBJETIVO: Avaliar a remodelacao da matriz extracelular na degeneracao do disco intervertebral atraves do modelo experimental degeneracao do disco intervertebral. METODOS: O modelo de inducao da degeneracao discal, utilizando agulha 20G e rotacao de 360o, foi aplicado por 30 segundos entre a sexta/setima e oitava / nona vertebras coccigeas de ratos machos da linhagem Wistar. O nivel intermediario, entre a setima e oitava vertebras, foi tomado como controle, nao sendo submetido a puncao. A distribuicao de constituintes da matriz extracelular envolvidos com mecanismos de remodelamento e inflamacao, como proteoglicanos (agrecam, decorim, biglicam), fatores de crescimento (TGFβ), isoformas de heparanase (HPSE1, HPSE2), metaloprotease-9 (MMP9) e interleucinas (IL-6, IL-10) foram avaliadas no periodo pos-lesao (15 e 30 dias) e no grupo controle (discos coletados imediatamente apos a puncao, dia zero). No 15o dia, fase aguda da doenca, notou-se reducao da expressao dos constituintes da matriz extracelular, porem nao houve diferencas na expressao de interleucinas. Aos 30 dias, as moleculas seguiram um padrao de expressao muito similar ao grupo controle (nao acometido por degeneracao discal). RESULTADOS: Os resultados mostram que na fase aguda ocorrem alteracoes significativas na matriz extracelular e, na fase tardia, o disco intervertebral retorna a um perfil semelhante ao tecido nao acometido por degeneracao, provavelmente devido a um intenso processo de remodelamento da matriz extracelular que e capaz de regenerar o tecido lesionado. CONCLUSAO: O modelo experimental utilizado demonstrou a ocorrencia de alteracoes significativas da matriz extracelular durante o periodo analisado apos a inducao da degeneracao do disco intervertebral. Trabalho experimental.

Computed tomographic evaluation of thoracic pedicle screw placement in idiopathic scoliosis.

This retrospective observational study aimed to determine the accuracy of the placement of transpedicular thoracic screws used in idiopathic scoliosis and to evaluate the position and safety of the implants using postoperative computed tomography. Twenty-nine patients who underwent surgery for scoliosis between May 2003 and November 2005 were included in this study. The mean spinal curvature was 67°, and all of the patients had thoracic screws or hooks implanted. The positioning of 78 pedicle screws was evaluated using computed tomography after the free-handed technique was performed. The mean spinal curvature after surgery was 29°. Seventy-six percent of the screws were fully contained within the pedicle. Twenty-one screws breached the pedicle by between 2 and 4 mm (three medially and 18 laterally). Two screws were broken. A neurological deficit was identified in one case after surgery, but the deficit was reversed after the removal of the screws. This screw had a medial breach of greater than 4 mm. Most screws were inserted between the cortical vertebrae. Misplaced screws were most commonly inserted with a lateral cortical perforation.

Fraturas com arrancamento do anel apofisário ("limbus") póstero-superior da vértebra L5, associado com hérnia discal pré-marginal em atletas

O aumento de adolescentes praticando esportes de forma cada vez mais competitiva tem causado o aumento de lesoes relacionadas a pratica desportiva. A dor lombar e uma queixa frequente entre os atletas, geralmente relacionada a contraturas da musculatura paravertebral e fraturas ( espondilolise ) devido ao excesso de treinamento e aplicacao de tecnicas incorretas. Porem, outras etiologias podem causar a dor lombar, como processos infecciosos, tumorais e fraturas. As fraturas com arrancamento do anel apofisario sao lesoes incomuns e raramente ocorrem na regiao postero-superior da vertebra L5. Os relatos da literatura mostram que o local mais acometido e a regiao postero-inferior da vertebra L4. Apresentamos dois casos de atletas jovens com esta incomum lesao. O objetivo deste trabalho e discutir a possivel etiologia, os melhores metodos para o diagnostico e possiveis formas de tratamento desta patologia.

Expression of heparanase isoforms in intervertebral discs classified according to Pfirrmann grading system for disc degeneration.

Study Design. This is a quantitative study of heparanase isoforms expression in degenerative and nondegenerative intervertebral discs (IVDs). Objective. To quantify the expression of both heparanase isoforms (HPSE1 and HPSE2) in IVD tissues as classified by different degeneration grades using the Pfirrmann grading system, and to correlate the expression with the loss of extracellular matrix molecules observed in patients with the disease. Summary of Background Data. The loss of proteoglycans as observed in IVD degeneration may occur due to the enhanced expression of matrix degrading enzymes, such as heparanase. However, the heparanase function in IVD degeneration remains unclear. Methods. This study comprised 53 surgical samples of degenerative discs obtained from patients with lumbar disc degeneration and 12 control samples collected from healthy individuals without any degenerative lumbar disc alterations who had accidental spine fractures. All patients underwent magnetic resonance imaging based on the Pfirrmann grading system for disc degeneration. Only the specimens that were classified according to magnetic resonance imaging evaluations as Pfirrmann grades I, II, III, and IV were analyzed. The tissue sections of the disc samples were subject to immunohistochemical staining with antibodies against the heparanase isoforms and to quantitative real time PCR to amplify heparanase isoforms cDNA. Protein and mRNA expressions were quantified. Analysis of variance and Student t test were used to compare the means of the study populations. Results. The data demonstrated a gradual increase in both the heparanase isoform protein expression and disc degeneration progression. Besides, mRNA expression of both heparanase isoforms were significantly higher in degenerative than nondegenerative IVDs. Conclusion. The overexpression of HPSE1 and HPSE2 in the intervertebral degenerated discs suggests a role for these factors in mediating extracellular matrix remodeling in degenerative discs during disease development.