Abstract Purpose: To evaluate the effects of mesenchymal stem cells on liver regeneration in rats following a 70% hepatectomy. Methods: Forty rats were subjected to 70% hepatectomy and then ~106 mesenchymal stem cells (test group), or saline solution (control group), were infused into their livers via the portal vein. Each treatment group was divided into early and late subgroups (euthanized 3 d and 5 d following the operation, respectively). Group comparisons of Albumin, aminotransaminases (AST, ALT), and Alcaline Phosphatase (AP) levels, proliferative index (ki-67+ straining), and mitotic cell counts were conducted. Results: No significant differences in liver regeneration rate, number of mitoses, proliferative index, or serum levels of albumin, AST, or AP were observed. ALT levels were higher in the test group than in the control group (p<.05). Conclusions: Mesenchymal stem-cell therapy did not improve liver regeneration rate 3 d or 5 d after 70% hepatectomy in rats. Likewise, the therapy appeared not to affect liver function, proliferative index, or number of mitoses significantly.

OBJETIVO: Determinar o valor agregado da fase sem meio de contraste da tomografia computadorizada do abdome em pacientes sem diagnóstico determinado ou em estadiamento tumoral. MATERIAIS E MÉTODOS: Estudo prospectivo e transversal em 100 pacientes consecutivos submetidos a tomografia computadorizada abdominal sem e com meio de contraste intravenoso. Dois examinadores avaliaram todos os exames, procurando estabelecer, através da fase com meio de contraste intravenoso (primeira análise) e posteriormente através da fase sem contraste (segunda análise), o diagnóstico principal e os secundários em função da indicação clínica do exame. Mediu-se a freqüência de mudança diagnóstica decorrente da análise combinada das fases pré- e pós-contraste intravenoso. Casos que tiveram mudança diagnóstica foram avaliados por especialistas clínicos para determinar se implicaria mudanças de conduta. RESULTADOS: Diagnósticos principal e secundário foram modificados em 1 e 18 casos, respectivamente (p = 1,000; p = 0,143). Os diagnósticos modificados foram: esteatose, definição de nódulo em adrenal, nefrolitíase, classificação de cistos renais e calcificação hepática. Nos casos em que a fase sem contraste modificou o diagnóstico, os especialistas mudaram sua conduta em 14/19 (73%) dos pacientes (p = 0,038). CONCLUSÃO: A fase sem contraste não modificou significativamente o diagnóstico principal ou secundário. Porém, as mudanças nos diagnósticos secundários influenciaram na conduta adotada pelos especialistas.

OBJECTIVE: To determine the role of the unenhanced phase of abdominal computed tomography in patients without a definite diagnosis or undergoing tumor staging. MATERIALS AND METHODS: A prospective and transversal study was developed with 100 consecutive patients submitted to unenhanced and contrast-enhanced abdominal computed tomography. Two observers evaluated all the computed tomography images in the contrast-enhanced phase (first analysis) and, later, in the unenhanced phase (second analysis) in an attempt to establish the primary and secondary diagnoses as a function of the clinical indication for the study. The frequency of changes in the diagnoses resulting from a combined analysis of the images in the pre- and post-contrast phases was evaluated. Cases with changes in the diagnosis were reviewed by clinical specialists for determining possible changes in the therapeutic approach. RESULTS: Primary and secondary diagnoses were changed in respectively 1 and 18 cases (p = 1.000; p = 0.143) as follows: steatosis, adrenal nodules, nephrolithiasis, renal cysts and hepatic calcification. In the cases where the unenhanced phase changed the diagnosis, the specialists changed the therapeutic approach in 14 of the 19 patients (73%) (p = 0.038). CONCLUSION: No significant change was observed in the primary or secondary diagnosis as a result of the findings in the unenhanced phase. However, changes in secondary diagnoses affected the therapeutic approach adopted by the specialists.