Experimental study of the participation of the vertebral endplate in the integration of bone grafts.

The surgical technique of anterior vertebral arthrodesis has been modified by the introduction of cages in spinal surgery. The classical technique recommends removal of the vertebral endplate and exposure of bleeding cancellous bone. However, after the observation of cage subsidence during postoperative follow-up, the vertebral endplate is no longer removed, due to its greater mechanical resistance which can prevent cage subsidence. The mechanical characteristics of the vertebral endplate are well known, in contrast to its osteogenic potential, which was investigated in the present experimental study. The study was conducted on mongrel dogs of both sexes, which were submitted to anterior corpectomy at the cervical spine level. A cortico-cancellous bone graft removed from the tibia was used for the reconstruction of the vertebral segment, which was used with osteosynthesis plates. At the site of contact between the surface of the vertebral body and the bone graft, the vertebral endplate was completely removed and cancellous bone was exposed in the inferior vertebra, whereas in the superior vertebra of the arthrodesed vertebral segment only curettage was performed, and the vertebral endplate was preserved, as recommended for cage implantation. Twenty adult dogs of both sexes were divided into four experimental groups according to time of sacrifice (15, 30, 90, and 180 days). The consolidation of the bone graft with the vertebral body was evaluated by histology using hematoxilin-eosin and Gomori trichrome staining. In the interface between the bone graft and the vertebral body surface in which the vertebral endplate was not removed, graft consolidation was not observed in any of the group I animals (sacrificed after 15 days), and was observed in 1/5 animals of group II (30 days), in 2/5 animals of group III (90 days), and in 4/5 animals of group IV (180 days). In the interface between the graft and the vertebral body in which the vertebral endplate was removed, bone-graft consolidation was observed in all animals of all experimental groups (15, 30, 90, and 180 days). Bone-graft consolidation with the surface of the vertebral body was influenced by the removal or maintenance of the vertebral endplate. Due to the importance of this structure in current surgical procedures, this phenomenon deserves to be studied in more detail in order to understand the basic events involved in this process.

Alpha-SM actin expression as prognostic indicator in IgA nephropathy (Berger's disease).

Recent studies have demonstrated that alpha-Smooth Muscle actin expression in glomerular and tubulointerstitial compartments of renal tissue could represent a prognostic marker in several renal diseases. Our objective was to identify the prognostic value of alpha-SM actin actin expression on the evolution of renal damage in Primary IgA nephropathy (Berger's disease). 43 patients followed up from 1988 to 1999 at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of Sao Paulo, Brazil, was studied. Clinical-laboratory data were obtained from the medical records of the patients using a protocol containing name, race, gender, origin, profession, age at clinical presentation of the disease and personal and family history. The parameters assessed in the approach to IgA nephropathy were serum creatinine, creatinine clearance, serum albumin, total serum protein, 24 hours proteinuria, glycaemia, serum sodium, potassium, calcium and phosphorus ions, analysis of urinary sediment, serum complement profile, blood count, and renal biopsy. Morphological evaluation was performed by renal biopsy using common light and immunofluorescence microscopy. Immunohistochemical studies were performed using a murine monoclonal antibody to alpha-SM actin. Our data showed that alpha-SM actin expression in the glomerular and tubulointerstitial compartments are not correlated with unfavorable clinical course of primary IgA nephropathy.

Classes, activity and chronicity indices, and alpha-smooth muscle actin expression as prognostic parameters in lupus nephritis outcome.

Renal biopsies of 86 patients with lupus nephritis were assessed according to the WHO classification, and according to activity and chronicity indices. The aim of the present study was to correlate clinical, and histological features (WHO class, activity and chronicity indices, and alpha-SM actin expression) with the progression of lupus nephritis, and identify the pathological role of alpha-SM actin in lupus nephritis. The median follow-up time was 75.5 +/- 57.3 months. Two patients were grouped as WHO class IIa lupus nephritis, eight patients as class IIb, 16 patients as class III, 25 patients as class IV, 15 patients as class V, and 19 patients as mixed pattern lupus nephritis. Sex, age, race, and the alpha-SM actin expression in glomeruli and tubulo-interstitial area in WHO class III and IV showed no correlation with clinical follow-up outcome of lupus nephritis. Unfavorable clinical outcome of lupus nephritis was correlated with WHO class IV compared to the other classes, and with the chronicity index in WHO class III patients.

Expressäo imunohistoquímica do MIB-1 em carcinoma de células transicionais de bexiga / Immunohistochemical expression of MIB-1 in transitional cell carcinomas of the bladder

A expressäo do MIB-1 é um excelente marcador da atividade proliferativa e correlaciona-se com a agressividade biológica do carcinoma de células transicionais da bexiga.Correlacionamos a expressäo do MIB-1 com a evoluçäo dos pacientes. Revisamos 90 pacientes do HC-FMRP-USP entre 1980-2000, com idade entre 29 a 93 anos (média 71 anos);sendo 70 (77,8 por cento) homens e 20 (22,2 por cento) mulheres; e seguidos em média por 55 (2-231) meses. 45 (50 por cento) tumores tinham grau I, 29 (32,2 por cento) grau II e 16 (17,8 por cento) grau III. Os tumores foram estadiados em pTA: 54 (60 por cento), pT1: 8 (8,9 por cento) e pT2-4: 28 (31,1 por cento). Foi utilizado o anticorpo monoclonal anti-MIB-1 (Immunotech). Emprega-se o limite de 10 por cento de núcleos corados como nível de corte para o MIB-1. Utilizamos para análise estatística os testes Mann-Whitney, Kaplan-Meier, e log rank, e nível de significância 5 por cento. Expressaram MIB-1, 63 pacientes (70 por cento) variando de 0 a 80 por cento (mediana 5 por cento, média 22,8 por cento), com diferença significativa (P<0,05) entre tumores invasivos (pT2-4) e näo invasivos (pTA-1) e entre os estádios pTA e pT1 (P=0,01). Houve associaçäo com o grau dos tumores: significativa entre G1 e G2 (P<0,001) e G1 e G3 (P<0,001), e sem significância entre G2 e G3 (P=0,2). A relaçäo do MIB-1 com o tamanho da lesäo foi significante (P<0,02). As recidivas näo foram preditas pelo índice MIB-1 (P=0,86), entretanto em pacientes MIB-1 positivos foi significantemente menor o intervalo livre de metástase (P=0.04), e a sobrevida entre tumores näo invasivos (P=0.009) e na populaçäo total (P=0.0002), Há correlaçäo entre a alta expressäo do MIB-1 e os estádios invasivos, os graus avançados e os tumores maiores, contudo, näo há diferença em tumores recidivados. O índice de positividade do MIB-1 näo distinguiu os pacientes com menor tempo livre da doença, foi, contudo, significante para apontar aqueles com menor sobrevida e tempo livre de metástase.