Collagen fiber reorganization in the rat ventral prostate following androgen deprivation: A possible role for smooth muscle cells

BACKGROUND. Stroma plays an essential role in glandular function in different systems. In the prostate, it is responsible for the development and maintenance of the differentiated state of the epithelium. The marked reduction in the epithelial compartment of the prostate gland following castration is followed by a similarly important reorganization of the stroma. In this work, we characterized the reorganization of collagen fibers in the ventral prostate of castrated rats. METHODS. Histochemical tests and immunohistochemistry for type I and III collagens plus confocal microscopy of triple-labeled (collagen III, actin, and DNA) tissue sections were employed. RESULTS. We showed that collagen fibers are composed of type I and type III collagens and that they are progressively concentrated around the epithelial structures (ducts and acini) and become increasingly undulated and folded. Double-labeling of collagen fibers and F-actin demonstrated that smooth muscle cells (SMC) are intimately associated with collagen fibers. CONCLUSIONS. The results demonstrated a marked reorganization of the collagen fibers, and suggest an active role of the SMC in the reorganization of the fibrillar components of the stroma. (C) 2000 Wiley-Liss, Inc.

Laparoscopic evaluation and treatment of the impalpable testis

Objectives: To evaluate the laparoscopic technique as a diagnostic and therapeutic tool in the management of patients with impalpable testis. Material and Methods: Fifty-nine patients with mean age of 6.3 years underwent laparoscopy to evaluate 85 impalpable testes that were classified as absent, canalicular and intra-abdominal. In the case of testicular absence, the procedure was terminated. In the case of canalicular testis, open inguinal exploration was performed. In intra-abdominal testis, either laparoscopic orchiopexy or orchiectomy was performed. According to the length of the vascular pedicle, orchipexy was performed either with or without vascular ligature. Post-operatively, the treated testes were evaluated according to size and location in the scrotum. Results: Seventeen (20%) of the 85 impalpable testes were diagnosed as absent, 21 (24.7%) as canalicular and 47 (55.3%) as intra-abdominal. Of the canalicular testes, 20 were explored by inguinotomy and one by laparoscopy. All the intra-abdominal testes were treated initially by laparoscopy, four being removed due to atrophy, 31 submitted to vascular ligature and 12 to primary orchipexy. Of those submitted to vascular ligature, 22 underwent a second stage orchipexy, of which 18 laparoscopically and 4 by inguinotomy. Of the 18 testes brought to the scrotum by staged laparoscopic orchipexy, 15 (83.3%) presented normal characteristics in the late follow-up, while of the 12 submitted to primary laparoscopic orchipexy, 8 (66.6%) were normal. There were no perioperative or late complications. Conclusions: Laparoscopy is a minimally invasive procedure with low morbidity that enables precise diagnosis of the impalpable testes. When intra-abdominal testes are found, either immediate laparoscopic orchiectomy, or primary and staged orchipexy are possible, with results equivalent to open procedures, with the advantage of smaller surgical incisions and shorter postoperative recovery.

Malignant transformation of pleomorphic xanthoastrocytoma: Case report

We report a case of a pleomorphic xantoastrocytoma which manifested itself as a cystic isodense lesion in the right fronto-temporal lobe in a 26 year-old woman. It appeared as a soft yellow tumor with cystic cavities on surgery. Five months after this surgery, the patient was submitted to a new operation, which revealed a friable tumor, easily differentiated from the normal parenchyma, with cystic components. The histopathological examination demonstrated pleomorphic xanthoastrocytoma with malignant transformation. Histologically, the tumor at first procedure was composed of pleomorphic astrocytes with multinucleated and foamy cells. A rare case of malignant transformation in pleomorphic xanthoastrocytoma is presented, discussed and illustrated in this paper.

Little cicada of sugarcane Mahanarva posticata (Homoptera: Cercopidae). A Brazilian agricultural pest. Morpho-histological study of salivary glands

Little cicadas are homopteran insect pests of sugarcane plantations. As these insects suck out the sap from the leaf parenchyma, they inoculate a toxic saliva that damages the plant vessels, thus promoting the loss of glucose by the affected plant. The morphological and histological analyses of the salivary glands of the little cicada Mahanarva posticata, revealed that these glands are formed by 2 portions: one portion comprises a group of acini and has been denominated as the principal gland; the second portion is filamentous in nature and has been denominated as the accessory gland; it is formed by very long and fine filaments. The acinous portion of the gland can be subdivided into 2 lobes: an anterior lobe formed by 3 lobules (I, II, III), and a posterior lobe formed by lobule IV and the excretory duct. Histologically, the salivary glands showed that the filaments are empty sutructures composed by several internal channels with secretion granules being observed in the cytoplasm of the cells of the secretory filaments. Lobules I and II of the principal gland are characterized by being highly basophilic and for accumulating a large amount of secretion in both the cytoplasm of the cells and inside secretion vesicles. Histochemically, we verified that the secretion produced by these glands is lipidic and protein in nature, with the production of polysaccharides being very low. The differences in stain and appearance of the different regions of the salivary gland lead us to believe that the final glandular product is lipoproteic in nature.

Morphological aspects of Culex quinquefasciatus salivary glands

The salivary glands of Culex quinquefasciatus female mosquitoes are paired organs composed of two lateral lobes with proximal and distal secretory portions, and a medial lobe. All portions comprise a simple epithelium that surrounds a salivary duct. In the apical portion of the medial lobe, non-secretory cells strongly resemble cells involved in ion and water transport. The general architecture of the secretory portions is similar between lobes. The appearance of the secretory material and the morphological aspect of the apical cell membrane are the most distinctive features among the three secretory portions. Cells in the lateral proximal lobe display thin membrane projections extending into a translucent and finely filamentous secretory product. At the lateral distal portion, the apical cell membrane forms an intricate meshwork that encloses a dark secretory product. Medial lobe secretory cells also contain secretory cavities surrounded by intracytoplasmic vesicles, all containing a very dark and uniform product. Scattered cells holding numerous vacuoles, some of them containing a small and electron-dense granule eccentrically located and resembling those of the diffuse endocrine system, are frequently observed in the periphery of all secretory portions. Immunofluorescence assays revealed that the distal portion of the lateral lobes contains apyrase, an enzyme putatively responsible for platelet aggregation inhibition, diffusely distributed in the cell cytoplasm. © 2003 Elsevier Ltd. All rights reserved.

Cysts reabsorption in the testis of the bee wax pest Achroia grisella (Lepidoptera, Pyralidae) during spermatogenesis

The present paper reports the occurrence of testicular cysts degeneration during spermatogenesis of Achroia grisella, a Lepidoptera with dimorphic spermatogenesis, through ultrastrucutural studies. Signs of cysts degeneration can be detected in the last larval instar but it increases during pupation and early adulthood. The degeneration affects the eupyrene, as well apyrene cysts but it is not always possible to recognize which cysts are degenerating. Some morphological features of cysts degeneration resemble apoptosis.

Description of the nucleolar activity and karyotype in germinative cell lines of Rhodnius domesticus (Triatominae, Heteroptera)

The purpose of this work was to study the karyotype, spermatogenesis and nucleolar activity at meiosis, in the species Rhodnius domesticus (Heteroptera, Triatominae). The testicular tubules were cytologically prepared by the conventional method of cell crushing and subsequent application of cytogenetic staining techniques with lacto-acetic orcein and silver-ion impregnation. The species under study presented karyotype 2n= 20A+XY, the modal number of the subfamily Triatominae. The chromosomes presented no primary constriction and were therefore characterized as holocentric. It was observed that the sex chromosomes sometimes were located at the periphery, close to the ring formed by autosomes, at first meiotic division. At metaphases II, sex chromosomes were positioned in the center of the autosomal ring, thus evidencing a postreductional behavior. These same chromosomes showed late migration at anaphases and were clearly impregnated with silver-ions, suggesting they bore Nucleolar Organizer Regions. Dispersed nucleolar corpuscles in cytoplasm until telophase II and small dots in spermatids strongly impregnated with silver, could be seen. Thus, it may be inferred that, in triatomines, the nucleolus does not completely disappear but remains in the form of small corpuscles that have a role in cell differentiation.

Isolated Richter's syndrome in central nervous system: Case report

Diffuse large cell non Hodgkin's lymphoma associated with chronic lymphoid leukemia (CLL), or Richter's syndrome, is a rare and serious complication. Isolated Richter's syndrome in the central nervous system is very rare; only 12 cases have been reported. We describe a 74-year-old patient with diffuse large cell non Hodgkin's lymphoma in the right frontal region with the appearance of multiform glioblastoma.

Diagnosis of 5α-reductase type 2 deficiency: Contribution of anti-Müllerian hormone evaluation

Aim: To evaluate anti-Müllerian hormone (AMH) levels in patients with clinical and molecular diagnosis of 5α-reductase 2 deficiency. Patients and methods: Data from 14 patients whose age ranged from 21 days to 29 years were analyzed according to age and pubertal stage. Sexual ambiguity was rated as Prader III in 11 patients. LH, FSH, testosterone (T), dihydrotestosterone (DHT) and AMH serum levels were measured in all but two patients, who had been previously submitted to gonadectomy; T and DHT were also measured in 20 age-matched controls. Results: Gonadotropin levels were normal in all but one patient who retained gonads (six of whom had reached puberty) and T/DHT ratio was elevated in all patients when compared to controls. All prepubertal patients had AMH levels < -1 SD for age, while most pubertal patients had AMH levels compatible with pubertal stage. Conclusions: Prepubertal patients with 5α-reductase 2 deficiency have AMH values in the lower part of the normal range. These data indicate that T does not need to be converted to DHT to inhibit AMH secretion by Sertoli cells. © Freund Publishing House Ltd., London.

Fatores que afetam a oviposição de Bemisia tabaci (Genn.) biótipo B (Hemiptera: Aleyrodidae) na cultura algodoeira

The objective of this work was to evaluate the oviposition behavior of the whitefly Bemisia tabaci (Genn.) biotype B in relation to leaf position, plant age, and adult density on cotton plants. The genotype IAC 22 was used to do the tests. In free-choice tests, 20, 30 and 40 day-old plants were used to evaluate age efects and 40 day-old plants to study egg distribution in the plant and on the leaf surface. In a no-choice test, 20 day-old plants were used to evaluate densities of 50, 100 and 150 adults per plant. The lobe areas on the leaf surface and apical leaves were preferred for whitefly egg laying and therefore more suitable for egg sampling in cotton plants. The 20 day-old plants were preferred for oviposition, and the densities of 100 and 150 adults per plant ensured the number of eggs enough to discriminate cotton genotypes with different whitefly resistance degrees.

Tissue inhibitor of metalloproteinase-2 (TIMP-2) location in the ventral, lateral, dorsal and anterior lobes of rat prostate by immunohistochemistry

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a major role in extracellular matrix component degradation in several normal and abnormal tissue situations; they are also found in human seminal plasma. MMPs have been found in rat prostate secretions and are nearly lobe specific in expression pattern. The aim of this study was to evaluate whether TIMP-2, like other semen components, is expressed differently from different rat prostatic lobes. Immunohistochemical staining was performed in both young and adult rat ventral (VP), lateral (LP), dorsal (DP), and anterior (AP) prostatic lobes and confirmed by western blotting. TIMP-2 expression was found in the epithelial cells in the following sequence: LP > AP > DP > VP, in both young and adult rats. In this study, 100% of adult LP presented histological signs of prostatitis, where TIMP-2 immunostaining was positive in normal epithelium even with intraluminal neutrophils, but was reduced or absent in the epithelium with intraepithelial leukocytes or with periductal stroma disorganization associated with mononuclear cell infiltration. However, TIMP-2 expression in LP was not induced by prostatitis, since younger rat LPs were also strongly TIMP-2 positive. The distal and intermediate VP regions were TIMP-2 negative, but the proximal regions were strongly stained. Western blotting results confirmed the high TIMP-2 expression in the LP lobe. Thus, TIMP-2 is expressed differently between the prostatic lobes and is another nearly lobe-specific protein, which plays a role in the regulation of MMP activity in seminal plasma and glandular homeostasis. TIMP-2 is also another regional ductal variation of VP. Further studies should address whether TIMP-2 expression is related to the highest incidence of rat LP prostatitis and adenocarcinoma. © 2006 International Federation for Cell Biology.

On a new species of the genus Moenkhausia Eigenmann (Ostariophysi: Characidae)

A new species of the genus Moenkhausia is described from the middle portions of the Rio Tocantins and tentatively from the Río Apure in Venezuela, Río Orinoco drainage. It is diagnosed by the presence of a dark spot in the half proximal length of the upper caudal-fin lobe, and by the presence of a large, irregularly shaped humeral spot located above the sixth to ninth perforated lateral line scale which is more posteriorly positioned along the body side in relation to other members of the genus. The distribution pattern of the new species is discussed. Copyright © 2007. Magnolia Press.

Chromosomal similarities and differences among four Neotropical Elateridae (Conoderini and Pyrophorini) and other related species, with comments on the NOR patterns in Coleoptera

This work deals with the comparative cytogenetic analysis of four Neotropical Elateridae species and reviews the nucleolar organizer region (NOR) patterns on Coleoptera chromosomes, for the first time. The cytogenetic characterization of Conoderus malleatus (Conoderini), Pyrearinus candelarius, Pyrophorus divergens and Pyrophorus punctatissimus (Pyrophorini) was accomplished through the study of mitotic and meiotic cells submitted to standard (Giemsa) and differential staining [silver impregnation and GC-specific chromomycin A 3 (CMA 3) plus AT-specific 4′-6-diamidino-2-phenylindole (DAPI) fluorochromes]. The analysis of spermatogonial cells revealed the diploid numbers: 2n = 17 in C. malleatus and 2n = 15 in P. candelarius, P. divergens and P. punctatissimus. In these species, the X0 type sex-determination system and the acrocentric morphology of almost all chromosomes were observed. The study of meiotic cells of the four species revealed the occurrence of total synapsis between the autosomes, the presence of one terminal or interstitial chiasma in the majority of the bivalents, and the reductional behaviour and regular segregation of all chromosomes. Although the three Pyrophorini species demonstrated many similar karyotypical characteristics, there was one discrepancy, which was noted in the diplotene cells and concerns the number of bivalents with two chiasmata; P. candelarius only presented one bivalent, P. divergens showed two bivalents and P. punctatissimus exhibited up to four bivalents with two chiasmata. Testicular cells impregnated with silver nitrate demonstrated two terminal NORs located on the fourth autosomal pair of the Conoderini species and on the second autosomal pair of the three Pyrophorini representatives. Use of CMA 3/distamycin A (DA)/DAPI staining on the P. candelarius and P. punctatissimus chromosomes revealed that the CMA 3 labelled regions were coincident with the NORs. The main strategies of karyotypical differentiation that have occurred among the four Elateridae species and other related species, and the general trends of the NOR shifts during Coleoptera chromosomal evolution are discussed in this work. © 2007 The Authors.

Anatomical study on domestical fowl (Gallus domesticus) reproductive system

Lately, researchers have taken into consideration studies on birds since they represent an excellent nutritional source. There are several classical descriptions of the male reproductive tract, always aiming at establishing a correlation with shape, testicular size, age and sexual maturity. This study analyzed 50 male Gallus domesticus, 1 to 64 weeks old. The birds were collected with 10 days and then weekly until 24 weeks, following 37, 48, 59 and 64 weeks, and sacrificed by cervical displacement. It was observed the sintopies of testis with the other organs. Further, it was done the testicular measurement and then the statistical analysis by following the model of testis weight variation due to the animal age. Our results showed that the maximum weight of the right and left testes occurred with 167 and 210 days, respectively, what made us infer this species sexual maturity in this period.

Morfogênese do testículo de embriões e fetos de vacas da raça nelore (Bos taurus indicus)

The aim of this study was to accompany the process of testicular development from the non-differentiable phase to its complete formation. Embryos and fetuses of Nelore breed cows (Bos Taurus indicus) were obtained in slaughterhouses near the Uberlandia city, Minas Gerais. The gonads and the embryos were fixed in Bouin's fixative and afterwards processed for conventional optical microscopy. The gonadal was observed firstly in a 1.0 cm long embryo. In 2.5 cm long embryos the presence of the albuginea allows the sex identification. The mean thickness of the albuginea ranged from 29.08 to 558.45 mm. Gradually increase of vascularization of the albuginea and parenchyma is observed. The mediastinum is located centrally. There was a decrease in the space occupied by the testicular cords, from 63.71 to 41.99% of the total testes volume. Its diameter ranged from 31.68 to 48.80 mm. The diameter of germinal cells (and their nuclei) was from 12.27 (6.65) to 16.95 914.21) mm. The quantity of germinal cells by cross section of cord decreased from a maximum of 2.80 to 0.76. The total number of germinal cells was from 16 at the beginning of colonization of the gonad to 18.32 x 106 at the end of the study. The number of Sertoli's cells by cross section of cord ranged from 10.00 to 16.25. The results obtained show that the origin and formation of testes in embryos and fetuses from Nelore breed cows (Bos taurus indicus) does occur in a very similar way to what is described for Bos taurus taurus.