Maurício A. Chagas

Stromal and acinar components of the transition zone in normal and hyperplastic human prostate

Objective To analyse the histological components of the transition zone in both normal human prostate and benign prostatic hyperplasia (BPH), and to determine the volumetric density (Vv) of the different elements (connective tissue, smooth muscle cells, acini and total stroma).

Prostatic epithelial and luminal area in the transition zone acini: morphometric analysis in normal and hyperplastic human prostate

To analyse quantitatively the acini and changes in the acinar epithelium and lumen in the transitional zone of normal and hyperplastic human prostates.

The penis in diabetes: structural analysis of connective tissue and smooth muscle alterations in a rabbit model.

Study Type – Aetiology (case control)

The Impact of Non- and Genetically Modified Soybean Diets in Aorta Wall Remodeling

The aim of this study was to evaluate the influence of nongenetically modified soybean (non-GMS) and genetically modified soybean (GMS) meal on growth and cardiometabolic parameters in rats. Thirty male Wistar rats were divided into 3 groups (n= 10): non-GMS, GMS, and control group (CG). All animals received water and an isocaloric diet ad libitum for 455 d. Blood was drawn by cardiac puncture, and serum was separated for subsequent biochemical analyses (total cholesterol, triacylglycerols, insulin, glucose, and testosterone). The aorta was quickly harvested and fixed; the body fat mass was removed and weighed. Non-GMS and GMS had a growth index (GI) similar to CG but with a lower body weight (P < 0.05) and a lower amount of body fat mass (P < 0.05). Total cholesterol, triacylglycerol, glucose concentrations, and aortic tunics were reduced (P < 0.05) in non-GMS and GMS compared to CG. Non-GMS and GMS are able to reduced serum cholesterol, triacylglycerols, glucose, and aortic remodeling in aged rats. No differences were observed between non-GMS and GMS in all parameters.

Maternal consumption of flaxseed during lactation affects weight and hemoglobin level of offspring in rats

OBJECTIVE: To investigate the effects of maternal flaxseed consumption during lactation on the body weight, hematological indicators and visceral fat mass of male offspring in adulthood. METHODS: Sixteen female Wistar rats were divided into two groups after giving birth. During lactation the control group (CG) was fed a casein-based diet and the flaxseed group (FG) was fed a casein-based diet containing 25% flaxseed. After weaning, male offspring were fed on commercial chow until adulthood and euthanized at 170 days for blood collection and visceral fat mass assessment. RESULTS: Offspring of rats in the FG had lower body weight (FG = 42.69±3.06 g; CG = 47.31±4.72 g; p = 0.036) at weaning. At 170 days, lower hemoglobin levels were observed in the FG (FG = 12.30±1.28 g/dL; CG = 13.88±0.91 g/dL; p = 0.02). There was no statistically significant difference in visceral fat mass between groups. CONCLUSIONS: Maternal consumption of a flaxseed-based diet during lactation resulted in lower body weight at weaning and lower hemoglobin levels in adulthood, when compared with the control group.

Sinusoidal Constriction and Vascular Hypertrophy in the Diabetes-Induced Rabbit Penis

OBJECTIVE To assess the morphological changes of penile vascular structures and the corpus cavernosum area in alloxan-induced diabetic rabbits. MATERIALS AND METHODS Twenty male rabbits (2 months old) were divided into two groups with 10 rabbits each, the control group (CG) and the diabetic group (DG). The animals from DG received an intravenous injection of alloxan (100mg/kg) to induce the diabetes. Ten weeks after the induction of diabetes, all animals were euthanized. Two fragments of the penile shaft were harvested and samples were processed and paraffin embedded. Sections (5 µm) were cut and stained for histological and immunohistochemical markers. RESULTS Nuclear protrusion toward the lumen, and cytoplasmic vacuolization were observed in the tunica intima of the dorsal artery of the penis in DG. The thicknesses of the tunica media increased significantly in DG (p = 0.0350). It was also observed a significant increase in the area of the tunica media (p = 0.0179). There was no significant change in smooth muscle cell density in the tunica media of the dorsal artery of the penis (p = 0.0855). The collagen fiber pattern of the tunica adventitia of the dorsal artery of the penis was different between the control and diabetic groups. There was a significant decrease in the area occupied by the cavernous sinuses in DG (p = 0.0013). CONCLUSION Alloxan-induced diabetes mellitus in rabbits promotes important changes in penile vascular structures, thereby decreasing blood supply and affecting penile hemodynamics, leading to erectile dysfunction.

Age-related changes in the concentration of elastic fibers in different regions of the rabbit penis.

PURPOSE: To investigate whether elastic fiber content in the corpus cavernosum (CC), corpus spongiosum (CS) and tunica albuginea (TA) of the rabbit penis undergoes modifications with age. METHODS: Rabbits were sacrificed, in groups of ten animals each, at 30, 120, 240, and 730 days of age. Histological sections were obtained from the penile middle shaft and were stained with Weigerts resorsin fuchsin. The content of elastic fibers was determined using stereological methods, and was expressed as volume fraction. RESULTS: At 730 days of age, elastic fiber content was increased by 54% (p<0.004), 78% (p<0.004), and 87% (p<0.004) in the TA, CC, and CS, respectively, compared with animals aged 30 days. After 30 days of age, the concentration gradually and significantly increased until 240 days of age. In 730-day old animals, the concentration, compared with the previous age group, was unchanged in the CC and decreased by 20% (p<0.004) in the TA. CONCLUSIONS: Elastic fiber contents in the rabbit penis correlate with properties of penile tissues. Although after one month of age there is a gradual increase in these concentrations, in two-year old animals this trend is interrupted, which suggests that this could be an early alteration due to senescence.

Stereological study of the elastic fiber and smooth muscle cell system in the bovine and buffalo penis

Samples of ten penises of Mediterranean buffaloes and ten penises of Red Sindhi cattle were used. The thickness of the tunica albuginea (TA), distribution of smooth muscle cells (SMC) and volume density (Vv) of elastic system fibers in TA, corpus cavernosum (CC) and corpus spongiosum (CS) were evaluated. The Vv of elastic system fibers in buffalo and bovine penis was respectively 4.07% ±0.88% and 3.36% ±1.21% in TA; 17.32% ±2.21% and 13.14% ±1.27% (CC), 26.58% ±4.31% and 31.36% ±3.67% (CS). The CC of buffalo presented higher Vv of elastic fibers than bovine, while in the CS the Vv of elastic fibers in buffaloes was smaller than in cattle. The TA thickness showed a significant difference among the species studied. The arrangement of SMC in the bovine penises and in the water buffalo suggests that this pattern is common to animals that have fibroelastic penises.