Renato Tambara Filho

Surgical reduction of the renal mass in rats: morphologic and functional analysis on the remnant kidney

PURPOSE This study has analyzed the biochemical and morphological effects on the remnant kidney in rats which were submitted to progressive surgical ablation of renal mass. METHODS Sixty Wistar male rats, weighing between 210 and 380g, were used and they were distributed in 3 groups of 20 animals each. The rats from the groups called 1, 2 and 3 were submitted to the surgical removal of renal tissue equivalent to 1/2, 2/3 and 5/6 of the whole renal mass, respectively. Then the groups were subdivided into 2 subgroups and they were operated again within 24 hours (subgroups 1B, 2B and 3B) and within 8 weeks (subgroups 1C, 2C and 3C) for the removal of the remnant kidney. 24-hour urine and blood were collected to analyze serum creatinine, clearance of creatinine and proteinuria in the first surgical intervention and at the time of the re-operation. The remnant kidney was submitted to a macroscopic evaluation for the degree of hypertrophy and to the analysis of histology. RESULTS There was a significant increase of the volume of the remnant kidney (164%) and glomerular sclerosis was present in 40% of the animals submitted to the ablation of 5/6 of renal mass. Functional alterations characterized by the increase of urinary excretion of proteins (50% in group 3), rise in the serum creatinine (261% subgroup 2B; 371% subgroup 3B, 118% subgroup 3C) and a significant reduction of the clearance of creatinine (control x subgroup 3C = 2,88 x 1,15 ml/min: p<0,05 were also observed. CONCLUSION The compensatory renal hypertrophy, as well as the glomerular injury translated in the form of proteinuria and sclerosis, are closed related to the volume of the remnant kidney, thus they are more evident when a greater fraction of the renal tissue is excised.

The significance of biological, environmental, and social risk factors for prostate cancer in a cohort study in Brazil

PURPOSE To evaluate the significance of several risk factors for prostate cancer in a cohort of Brazilian men. SUBJECTS AND METHODS Men ≥ 40 years-old participating in a prostate cancer screening program between December 2006 and April 2011 in the city of Curitiba, Brazil, were evaluated to determine the prevalence, relative risk (RR) and 95 % CI of prostate cancer according to age, race, ethnicity, family history of prostate cancer, educational level, and history of vasectomy, increased blood pressure, diabetes mellitus, and urethritis. RESULTS In 2121 men included in this study, prostate cancer prevalence was 0.6 % for men between 40-49 years versus 2.0 % (adjusted RR = 2.58), 7.7 % (adjusted RR = 5.76), and 8.4 % (adjusted RR = 4.88) for men 50-59 years, 60-69 years, and ≥ 70 years, respectively (p < 0.05 to all). The prevalence of cancer was 5.1% in blacks versus 3.3 % in whites (adjusted RR = 1.56, p > 0.05); 6.1 % in African descendants, in comparison to 3.0 % in non-African descendants (adjusted RR = 3.17, p < 0.05); 5.1% in men with a positive family history, compared to 2.5 % in those with no family history (adjusted RR = 1.55, p > 0.05); and 4.8 % in participants with incomplete elementary school level or lower, compared to 2.2 % in men with complete elementary school level or higher education (adjusted RR = 1.85, p > 0.05). Men with/without history of vasectomy, increased blood pressure, diabetes, and urethritis had a prostate cancer prevalence of 0.8 %/3.0 % (adjusted RR = 0.23, p > 0.05), 3.8 %/2.2 % (adjusted RR = 1.16, p > 0.05), 3.7 %/2.6 % (adjusted RR = 1.39, p > 0.05), and 2.6 %/2.6 % (adjusted RR = 0.99, p > 0.05), respectively. CONCLUSIONS Risk factors associated with an increased prevalence of prostate cancer in this cohort included increasing age and African ethnicity.

The prevalence of prostate cancer in Brazil is higher in Black men than in White men: systematic review and meta-analysis

BACKGROUND Black men have a higher incidence of prostate cancer compared with White men in several countries. In Brazil, most studies reported a similar prevalence of prostate cancer between Blacks and Whites as a result of the high race mixture of the population. OBJECTIVE To perform a systematic review with meta-analysis of the prevalence of prostate cancer in Black versus White, Brown versus White, and Black versus Brown Brazilian men. DESIGN, SETTING, AND PARTICIPANTS This systematic review included cohort, cross sectional and case-control studies comparing the prevalence of prostate cancer between races in Brazil. It was performed using an electronic search of references in bibliographic databases, and dissertations and theses databases from several Brazilian hospitals, universities, and schools of medicine. Meta-analysis was conducted using the RevMan software from the Cochrane Collaboration. To control for potential confounding variables, sensitivity analyses excluding case-control and cross sectional studies were performed. MEASUREMENTS The outcomes of interest included the number of participants, prevalence of prostate cancer, and odds ratio of cancer between Black and White men, Brown and White men, and Black and Brown men. RESULTS AND LIMITATIONS Twelve studies approaching the prevalence of prostate cancer in Black or Brown vs. White men in Brazil were identified, totalizing 41388 participants. The prevalence of prostate cancer was 9.6% in Black vs. 5.6% in White men (OR 1.58), 10.1% in Black vs. 6.7% in Brown men (OR 1.43), and 6.7% in Brown vs. 6.6% in White men (OR 1.14). Limitations of this review reflect the complexity and ambiguity in the definition of who is Black and who is not in such an heterogeneous population like the Brazilian people. CONCLUSIONS This systematic review with meta-analysis demonstrates a higher prevalence of prostate cancer in Black men compared to White or Brown Brazilian men. The prevalence of prostate cancer is similar in Brown versus White men.

Ipsilateral testicular necrosis and atrophy after 1,080-degree torsion of the spermatic cord in rats

PURPOSE To assess the incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord, and 60 days after detorsion of the spermatic cord. METHODS 42 rats were divided in 7 groups. Except for the control group, surgical torsion of the right spermatic cord was performed in all groups (T0). After 1, 2, or 4 hours of torsion, each group underwent either ipsilateral orchiectomy (groups OT1, OT2, and OT4), or detorsion of the spermatic cord and observation for 60 days (groups DT1, DT2, and DT4), before they were evaluated for the presence of testicular necrosis/atrophy. RESULTS Only one rat (5.5%) in groups OT1, OT2, and OT4 had testicular necrosis, in comparison with six rats (33.3%) in groups DT1, DT2, and DT4 (p=0.04). The incidence of testicular necrosis/atrophy was not different between subgroups T1, T2, and T4, and the control group (p>0.05). There was, however, a tendency toward greater incidence of necrosis/atrophy in the rats in group DT4. CONCLUSION The incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord is 5.5%, in comparison with 33.3% sixty days after detorsion of the spermatic cord.

Long-term effects of the testicular torsion on the spermatogenesis of the contralateral testis and the preventive value of the twisted testis orchiepididymectomy

PURPOSE To determine whether the testicular torsion causes long-term effects on the spermatogenesis of the contralateral testis, and whether the orchiepididymectomy of the twisted testis could prevent them, using specific spermatogenesis parameters to elucidate the conflicting results in the literature. METHODS Seventy-four pubertal male Wistar rats were randomly selected. The experimental group consisted of 40 rats, divided into four subgroups, submitted to 1.080 degrees counterclockwise left testicular torsion and its scrotal fixation at the beginning of the experiment, and left orchiepididymectomy at one, five, ten and 90 days, respectively. The control group consisted of 24 rats, divided into four sham operation control subgroups. An additional control subgroup consisted of the ten remaining rats, submitted only to the left orchiepididymectomy at the beginning. At 90 days, the contralateral testes of the experimental and control subgroups were collected for the evaluation of their spermatogenesis parameters: testicular weight, seminiferous tubular diameter, Johnsen score and differential counting of the germ cells. RESULTS No statistically significant differences were observed among the experimental and control subgroups for all of the spermatogenesis parameters of the contralateral testes. CONCLUSIONS Testicular torsion does not cause long-term effects on the spermatogenesis of the contralateral testis in pubertal rats, and the orchiepididymectomy of the twisted testis is not necessary for preventive purposes for the contralateral spermatogenesis.

Effects of the pneumoperitoneum in rats submitted to a unilateral nephrectomy: morphologic and functional study on the remnant kidney

PURPOSE The aim of this experimental study is to analyze the morphologic and functional effects of the pneumoperitoneum on the remnant kidney in rats submitted to a unilateral nephrectomy. METHODS Forty-eight male adults Wistar rats, with an average weight between 240 to 350 g, were distributed in three groups. The rats in Group 1 were subdivided into two other subgroups: Control Group IA and lB. Groups 2 and 3 and respective subgroups included 12 rats each. All animals were anesthetized and submitted to a puncture. Animals in Groups 2 and 3 were submitted to abdominal insufflation with CO2, during 2 and 4 hours respectively, with a constant IAP of 15 mmHg. Rats of the Control Group 1A and 1B were maintained punctured during 2 and 4 hours respectively, however, without insufflation. In the end of this period, a left nephrectomy was performed in all animals. After 4 weeks, a new pneumoperitoneum with the same duration was installed, according to the groups. After 8 weeks, the animals were submitted to euthanasia to remove the remnant kidney. Samples of blood were collected during the whole experiment to evaluated the renal function by dosing serum creatinine. The remnant kidney was analyzed microscopically to evaluate its level of glomerular hypertrophy, the number ofmesangial cells, and to observe the presence of glomerular sclerosis. All groups were kept under observation and the results were submitted to statistical analysis by a longitudinal and transversal comparative study. RESULTS At the evaluation of residual renal function no significant clinical alteration was seen in rats submitted to pneumoperitoneum during 2 and 4 hours after a period of 8 weeks. The morphologic analysis of the remnant kidney showed no histological renal injury in the groups. CONCLUSION The function and renal morphology of rats submitted to a unilateral nephrectomy were not significantly influenced by prolonged and successive pneumoperitoneum, according to this studys biochemical and histological findings.

Patient positioning during digital rectal examination of the prostate: preferences, tolerability, and results

PURPOSE To evaluate the preferred position used by Brazilian Urologists to perform DRE, the position that Brazilian patients prefer or think it is less embarrassing to have a DRE, and to evaluate the results of DRE with patients in left lateral decubitus, modified lithotomy, standing-up, or the physician will have them place their elbows on the table and squat down slightly. MATERIALS AND METHODS Brazilian Urologists were contacted by e-mail, and 200 patients answered a questionnaire while undergoing prostate cancer screening. RESULTS The preferred position was modified lithotomy position reported by 63.4% of Urologists, and left lateral position reported by 42.7% of the patients. Total DRE time was lower in the standing-up position. Pain and urinary urgency scores were similar regardless of the position used, and bowel urgency score was higher in patients squatting down. Patients were similar in terms of age and PSA level, but there was a significant difference between the standard deviations of estimated prostate weight in left lateral position. There were no differences in prostate asymmetry, positive DRE, or incomplete palpation of the prostate rates among different examination positions. CONCLUSIONS Despite individual subjective preferences, a faster examination time in the standing-up position, and higher bowel urgency scores in patients with their elbows placed on the table and squatting down slightly, there were similar rates of prostate asymmetry, positive DRE, and incomplete palpation of the prostate, and comparable patient tolerability among different examination techniques.

Influence of ultrafine wet grinding on pozzolanic activity of submicrometre sugar cane bagasse ash

Abstract Abstract Sugar cane bagasse ash is an important byproduct of sugar and alcohol production. This residual material requires only grinding and classification in order to achieve adequate fineness and homogeneity to be used as pozzolanic admixture in concrete. In this study, submicrometre ashes were produced from wet grinding using a planetary ball mill. Measurements of the pozzolanic activity of the ashes with cement and lime were carried using mechanical methods based on the compressive strength of mortars. It was observed that the pozzolanic activity of submicrometre ashes is inversely correlated to its particle size. Moreover, it was demonstrated that the grinding intensity clearly increased the sugar cane bagasse ash reactivity.

Prevalence and risk factors for penile lesions/anomalies in a cohort of Brazilian men ≥ 40 years of age

PURPOSE To report the prevalence and risk factors of penile lesions/anomalies in a Metropolitan Brazilian city. MATERIALS AND METHODS All participants undergoing prostate cancer screening in the city of Curitiba were systematically examined to identify penile lesions including cutaneous mycosis, sexually transmitted diseases, penile cancer, meatal stenosis, hypospadias, and Peyronies disease. Outcomes of interest included the prevalence and the relative risk and 95% confidence intervals of the lesions/anomalies according to age, school level, race, personal history of diabetes, arterial hypertension, nonspecific urethritis, and vasectomy. RESULTS Balanoposthitis occurred in 11.8% of all participants, with an increased risk in those with diabetes (RR = 1.73), or past history of nonspecific urethritis (RR = 1.58); tinea of the penis was present in 0.2% ; condyloma acuminata in 0.5% ; herpes virus infection in 0.4% ; urethral discharge in 0.2% ; genital vitiligo in 0.7%, with an increased prevalence in non-white men (RR = 4.43), and in subjects with lower school level (RR = 7.24); phimosis in 0.5%, with a nearly 7-fold increased risk in diabetics; lichen sclerosus in 0.3%; stenosis of the external urethral meatus in 0.7%, with a higher prevalence in subjects with lichen sclerosus (RR = 214.9), and in those older than 60 years of age (RR = 3.57); hypospadia in 0.6%; fibrosis suggestive of Peyronies disease in 0.9%, especially in men older than 60 years (RR = 4.59) and with diabetes (RR = 3.91); and penile cancer in 0.06%. CONCLUSION We estimated the prevalence and risk factors of commonly seen penile diseases in an adult cohort of Brazilian men.

Effects of immunosuppression with tacrolimus and mycophenolate mofetil on renal histology and function in single kidney rats submitted to ischemia and reperfusion

PURPOSE To evaluate renal histological changes and renal function in single kidney rats submitted to renal ischemia-reperfusion and to immunosuppression with tacrolimus and mycophenolate-mofetil. METHODS Experimental study with 80 Wistar rats distributed into control, Sham and six other groups treated with immunosuppressive drugs. Animals undergoing surgery, right nephrectomy and left renal clamping, killed on the 14th day and analyzed for renal histology, urea and creatinine. RESULTS The group receiving tacrolimus at higher doses (T3) showed renal histological lesions indicative of early nephrotoxicity, and significant increase in urea and creatinine. The group M (mycophenolate-mofetil alone) and the group M2 (mycophenolate-mofetil combined with half the usual dose of tacrolimus) presented a slight rise in serum urea. The groups using mycophenolate-mofetil alone or combined with tacrolimus showed creatinine levels similar to that of the group T3. CONCLUSIONS Histologically, the association of injury by ischemia-reperfusion with the use of tacrolimus or mycophenolate-mofetil alone demonstrated a higher rate of renal changes typical of early nephrotoxicity. In laboratory, the combination of injury by ischemia-reperfusion with tacrolimus at higher doses proved to be nephrotoxic.