Ultrasound method applied to characterize healthy femoral diaphysis of Wistar rats in vivo.

A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses of Wistar rats in vivo. Five quantitative parameters [apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), time slope of apparent backscatter (TSAB), integrated reflection coefficient (IRC), and frequency slope of integrated reflection (FSIR)] were calculated using the echoes from cortical and trabecular bone in the femurs of 14 Wistar rats. Signal acquisition was performed three times in each rat, with the ultrasound signal acquired along the femur's central region from three positions 1 mm apart from each other. The parameters estimated for the three positions were averaged to represent the femur diaphysis. The results showed that AIB, FSAB, TSAB, and IRC values were statistically similar, but the FSIR values from Experiments 1 and 3 were different. Furthermore, Pearson's correlation coefficient showed, in general, strong correlations among the parameters. The proposed protocol and calculated parameters demonstrated the potential to characterize the femur diaphysis of rats in vivo. The results are relevant because rats have a bone structure very similar to humans, and thus are an important step toward preclinical trials and subsequent application of QUS in humans.

Ultrasound method applied to characterize healthy femoral diaphysis of Wistar rats in vivo

A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses of Wistar rats in vivo. Five quantitative parameters [apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), time slope of apparent backscatter (TSAB), integrated reflection coefficient (IRC), and frequency slope of integrated reflection (FSIR)] were calculated using the echoes from cortical and trabecular bone in the femurs of 14 Wistar rats. Signal acquisition was performed three times in each rat, with the ultrasound signal acquired along the femur's central region from three positions 1 mm apart from each other. The parameters estimated for the three positions were averaged to represent the femur diaphysis. The results showed that AIB, FSAB, TSAB, and IRC values were statistically similar, but the FSIR values from Experiments 1 and 3 were different. Furthermore, Pearson's correlation coefficient showed, in general, strong correlations among the parameters. The proposed protocol and calculated parameters demonstrated the potential to characterize the femur diaphysis of rats in vivo. The results are relevant because rats have a bone structure very similar to humans, and thus are an important step toward preclinical trials and subsequent application of QUS in humans.

Urethral compliance in hypospadias operated by tubularized incised urethral plate (TIP) with and without a dorsal inlay graft: an experimental controlled study.

OBJECTIVE: Abnormal uroflowmetries are common after tubularized incised plate urethroplasties (TIP), perhaps due to low compliance. We hypothesized that (1) abnormal uroflowmetries after TIP might be caused by segmental lower compliance; (2) by adding a graft to the raw area in the incised plate (TIPG), compliance might be improved by preventing secondary intention healing of the dorsal incision. METHODS: A standardized penectomy was performed in 27 adult male rabbits: 9 normal non-operated controls (G1), 6 weeks after TIP (G2: n = 9) or TIPG (G3: n = 9). A standardized isolated segment (including the whole urethroplasty in G1 and G2) was progressively distended with air (1, 2 and 3 ml) in the 3 groups. The respective intraluminal pressures were measured with a tensiometer. RESULTS: Pressure measurements were feasible and reproducible for this model. Mean pressures tended to be higher in the experimental groups (G1: 59.7 mmHg vs. G2: 79.6 mmHg vs. G3: 100.1 mmHg for 1 ml injections; G1: 233.1 mmHg vs. G2: 241 mmHg vs. G3: 308.4 mmHg for 2 ml injections and G1: 457.3 mmHg vs. G2: 429 mmHg vs. G3: 520 mmHg for 3 ml injections) without reaching the statistical significance. CONCLUSION: In this model, the elasticity of the TIP or TIPG neourethras tended to be reduced when compared to controls. The placement of an inlay graft on the dorsal incised area did not increase the compliance. This model allows the measurement of segmental intraluminal urethral pressures generated by controlled air distension and may be a useful tool to evaluate the experimental urethroplasty models.

Immunological effects of acute testicular torsion on the contralateral testis in rats.

AIM: The mechanism by which unilateral testicular torsion leads to injury of the contralateral testis is still controversial. The present study aimed to evaluate immunohistopathological changes in the contralateral testis of rats after acute testicular torsion. METHODS: 40 pubertal rats were randomly divided into 3 groups. Group 1 (n=10) functioned as controls. Group 2 rats (n=10) underwent a sham operation, and Group 3 (n=20) underwent 720° torsion of the left spermatic cord (3 h) followed by detorsion (24 h). RESULTS: Immunofluorescence tests were done to investigate contralateral lesions in half of the animals in Group 3. Nitro blue tetrazolium (NBT) was injected in both testes to identify the presence of oxygen-derived free radicals. 24 h after reperfusion, bilateral samples of the testes were obtained for histological analysis. Fisher's exact test was used for statistical analysis with p-values <0.05 considered significant.Immunofluorescence tests were positive for the contralateral (right) testis but with a lower intensity than that of the testis submitted to torsion. NBT reaction was intense all over the left testis while a minor reaction was visible in the right testis. In Group 3 the left distorted testicle showed diffuse edema with cell elimination and extensive necrosis of the seminiferous tubules. Histological lesions were moderate to mild in the contralateral testis. CONCLUSION: An autoimmune IgG-mediated mechanism deposited on the basement membrane of seminiferous tubules seems to be involved in the genesis of contralateral testis injury.

Prediction of death using the Mannheim Peritonitis Index in oncologic patients

O Índice de Peritonite de Mannheim (MPI) é um sistema de escore idealizado para avaliar o prognóstico de pacientes com peritonite. Realizamos um estudo retrospectivo de oito anos dos prontuários de 89 pacientes com doença maligna e peritonite submetidos a cirurgia. O índice médio foi de 26.6 pontos (5-47), com sensibilidade de 87,3 por cento e especificidade de 41,2 por cento. A melhor acurácia (69,7 por cento) foi obtida com o escore de 21. Concluimos que o MPI foi um preditor de morte confiável em pacientes oncológicos com peritonite e pode ser de utilidade no planejamento e avaliação de futuras formas de tratamento nestes pacientes.

Intra-abdominal tuberculosis in acquired immunodeficiency syndrome. Diagnosis and management.

Tuberculosis (TB) in human immunodeficiency virus (HIV) immunosuppressed patients is characterized by extra-pulmonary disease in as many of 70% of them. If intestinal or lymph node involvement occurs, the differential diagnosis between an acute abdomen and other non surgical conditions may be a challenging problem. The authors analyzed eight double infected patients (TB and acquired immunodeficiency syndrome AIDS), who were admitted to the University Hospital (HUCFF) of the Federal University of Rio de Janeiro. This association should be considered when abdominal pain, anemia, fever, weight loss and abdominal lymph node enlargement are present. Bacteriology of body fluids, abdominal ultrasound (US) and computed tomography scans (CT) combined with guided needle aspiration biopsies, barium examination, colonoscopy and laparoscopy, can not only elucidate the diagnosis but also be helpful in assessing an appropriate management. Thus a systematic evaluation often yields an etiology and a correct therapeutic indication reducing the high mortality rate.