Study of the nucleolar cycle and ribosomal RNA distribution during meiosis in triatomines (Triatominae, Heteroptera)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diabetes induces stromal remodelling and increase in chondroitin sulphate proteoglycans of the rat ventral prostate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Meiotic chromosomes and nucleolar behavior in testicular cells of the grassland spittlebugs Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana (Hemiptera, Auchenorrhyncha)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cytogenetic analyses of two Curimatidae species (Pisces; Characiformes) from the Paranapanema and Tietê Rivers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Superficial keratectomy and 360º conjunctival flap for bullous keratopathy in a dog: a case report

Relata-se o caso ocorrido em um cão, da raça Pinscher, com dois anos de idade e histórico de desconforto no olho direito. O olho esquerdo havia sido enucleado por outro profissional, por apresentar os mesmos sinais, cujo tratamento clínico instituído não lograra êxito. O valor do teste da lágrima de Schirmer encontrava-se aumentado e identificou-se diminuição da pressão intraocular à tonometria de aplanação. Observaram-se, à biomicroscopia, edema corneal profuso e ceratocone, e o teste da fluoresceína foi negativo. Gonioscopia e oftalmoscopia não lograram fornecer dados relevantes dadas as condições da córnea. Diagnosticou-se ceratite bolhosa. Optou-se pelo tratamento cirúrgico, que fora realizado em duas etapas: 1- ceratectomia superficial e flap conjuntival de 360º; 2- ceratectomia superficial para devolver transparência à córnea. Transcorridos 30 dias da segunda ceratectomia superficial, o flap de terceira pálpebra foi desfeito. Observou-se conjuntivalização do quadrante nasal superior da córnea, córnea clara no eixo visual e retorno da visão.

Morphometry and histochemistry of the semitendinosus muscle of tufted capuchin monkeys (Cebus apella Linnaeus, 1758)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Surgical and chemical castration induce differential histological response in prostate lobes of Mongolian gerbil

The present study describes the short-term alterations in the prostate ventral and dorsal lobe of the adult Mongolian gerbil, in response to two different androgen suppression approaches. Groups (n = 6) of 16-week-old gerbils were maintained intact or subjected, either to the bilateral surgical castration I week previously or to daily subcutaneous injections of Flutamide (10 mg/kg body weight) for 7 days. The main microscopic features of both prostate lobes in these groups were compared using conventional paraffin tissue sections, measurements of acinar epithelial height and stereological data of main gland components (acini, collagen fibers and fibromuscular stroma). Marked alterations were observed in the basement membrane of the ventral lobe after both surgical and chemical castration, such as an increase in thickness and collagen staining. A low degree of epithelial atrophy was detected in the dorsal lobe following both androgen suppression approaches in comparison with that found in the ventral lobe, indicating that this lobe is not so responsive to testosterone ablation induced by castration or Flutamide treatment, at least insofar as secretory activity is concerned. However, the dorsal lobe exhibited marked stromal modification, such as an increase in collagen fibers following castration and an increase in fibromuscular stroma following Flutamide-treatment. Thus, the histological and quantitative data indicates a differential short-term response of the prostate dorsal lobe to surgical castration and Flutamide therapy, suggesting the existence of lobe-specific mechanisms for stromal remodeling. (c) 2006 Elsevier Ltd. All rights reserved.

X chromosome heterochromatic pattern and nucleolar synthesis in pupal ovaries of Aedes aegypti

C-banding and silver-staining techniques were used to examine pupal ovaries of Aedes aegypti from Sao Jose do Rio Preto (Brazil). Silver staining in ovary cystocytes showed two basic patterns relative to the nucleolar morphology: viz (1) a single, compact small body; and (2) multiple bodies encompassing large nuclear areas. These two types of cystocytes were present in the ratio of 7:1, which is the same as the number of nurse cells and oocytes, respectively, in each follicle. This suggests the possibility of eventually using such a nucleolar morphological difference to recognize both cell types in developmental stages before emergence. Silver nitrate staining in metaphase chromosomes revealed centromeric bands on all six chromosomes. The C-banding pattern in metaphase chromosomes showed an intercalary band in one of the X arms, as described previously in other populations. In ovary cystocytes (pachytene stage) this C-positive band seemed to consist of two chromomeres. Phase contrast microscopy showed that the nucleolus was associated with the distal chromomere of this intercalary C-band, indicating that the nucleolus organizer region was located in that part of the heterochromatic band.

Light microscopy and computer three-dimensional reconstruction of the blood capillaries of the enamel organ of rat molar tooth germs

We performed a light microscope and a computer three-dimensional reconstruction study of serial sections of the molar enamel organ of 3- and 5-day-old rats perfused with Indian ink through the arterial system. The tooth germs were fixed in Bouin's solution, embedded in paraffin, sectioned and stained with haematoxylin and eosin. For the three-dimensional reconstruction, light micrographs of the serial sections were digitized, and aligned using the serial EM Align software downloaded from http://synapses.bu.edu/tools/. After alignment, the boundaries of the India-ink-filled blood vessels were manually traced with a mouse using the software IGL trace (version 1.26b), also downloaded from the above website. After tracing, a three-dimensional representation of the blood vessel contours was generated in a VRML format and visualized with the help of the software Cortona Web3D viewer (version 4.0) downloaded from http://www.parallelgraphics.com/products/cortona. Our results showed that in regions where ameloblasts are polarized the capillaries are arranged in three distinct levels: (1) penetrating and leaving capillaries in relation to the outer enamel epithelium; (2) capillaries crossing and branching inside the stellate reticulum; and (3) capillaries branching and anastomosing profusely within the stratum intermedium, thereby forming an extensive capillary plexus intimately associated with the cells of the stratum intermedium. The existence of a conspicuous capillary plexus intermingled with cells of the stratum intermedium, as shown in our results, suggests that some molecules produced by cells of the stratum intermedium could be released into the capillary plexus and thereafter carried to the dental follicle.

CYTOGENETIC AND DNA CONTENT IN 6 GENERA OF THE FAMILY CALLICHTHYIDAE (PISCES, SILURIFORMES)

Cytogenetic studies involving conventional Giemsa staining, C-banding analysis and silver staining of NORs were performed on nine species belonging to six genera of the family Callichthyidae. The diploid number ranged from 2n = 44 to 2n = 100, the number of chromosomal pairs with NORs ranged from 1 to 4 and constitutive heterochromatin was mainly distributed in the centromeric and/or pericentromeric position of the chromosomes. The DNA content of erythrocytes from six species studied ranged from 1.18 +/- 0.07 to 2.77 +/- 0.22 pg/nucleus. The extensive variability in karyotypes and in nuclear DNA content detected are in accordance with the initial hypothesis that chromosome rearrangements and polyploidy have played a significant role in the evolutionary history of Callichthyidae.

Placentation in the capybara (Hydrochaerus hydrochaeris), agouti (Dasyprocta aguti) and paca (Agouti paca)

Placentae of three hystricimorph rodents-capybara, agouti and paca-were examined by conventional histology, immunohistochemistry for cytokeratin and vimentin, and TUNEL staining. The placentae were divided into lobules of labyrinthine syncytium separated by interlobular and marginal trophoblast. The subplacenta comprised cytotrophoblasts, supported on lamellae of allantoic mesoderm, and syncytiotrophoblast. The central excavation was still apparent in the definitive placenta of capybara. In agouti and paca, the decidua of the junctional zone formed a mesoplacenta comprising a capsule and a pedicle. Towards term the pedicle formed a tenuous attachment between placenta and uterine wall comprising a few maternal vessels surrounded by degraded tissue. In paca placenta, it was shown by TUNEL staining that breakdown of this tissue occurred by apoptosis. The visceral yolk sac was highly villous and, in agouti, the yolk sac villi were extremely long. Lateral to its attachment to the placenta, the fetal surface was covered with non-vascular yolk sac endoderm. A layer of spongiotrophoblast cells was interposed between the endoderm and the marginal trophoblast. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Collagen and reticular fibers in left ventricular muscle in diabetic rats: Physical exercise prevents its changes?

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytogenetic analysis of A-, B-chromosomes and ZZ/ZW sex chromosomes of Characidium gomesi (Teleostei, Characiformes, Crenuchidae)

Different cytogenetic techniques were used to analyze the chromosomes of Characidium gomesi with the main objective of comparing the base composition of ZZ/ZW sex-chromosomes, B-chromosomes and the heterochromatin of A-chromosomes. The results of digestion of chromosomes with AluI restriction endonuclease (RE), silver and CMA3 staining, C-banding and fluorescence in situ hybridization (FISH) with the 18S rDNA probe suggested the existence of compositional differences between the heterochromatin of ZZ/ZW sex-chromosomes, A- and B-chromosomes, and indicated the presence of different numbers and morphology of B-chromosomes in the samples of this population.

The effect of low intensity laser therapy on wound healing in Streptozotocin-induced diabetic rats

Diabetes Mellitus is a condition that results in a delay of the wound healing process, that is associated with an insufficient production of collagen, a decrease of the amount of collagen fibrils and deficient blood flow in the wound area. It is suggested that Low Intensity Laser Therapy acts by improving wound healing in normal organisms, accelerating tissue regeneration. The aim of this work was to investigate the biostimulatory effect of the HeNe laser irradiation, at 632.8 nm, on wound healing in 15 male rats suffering from diabetes induced by Streptozotocin, compared to 15 control diabetic animals. Irradiation parameters were: laser power of 15mW, exposition time of 17 s., irradiated area of 0.025 cm 2 and laser energy density of 10 J/cm 2. Full-thickness skin squared samples, with 5 mm of non-injured tissue around the wound, were obtained at 4, 7 and 15 days after wounding procedure (5 treated and 5 control animals each time). The histopathologic analysis performed by haematoxylin-eosin staining. Results suggested that the irradiation of diabetic rats was efficient for wound healing. Treated group presented better quality of the wound tissues by the macroscopic observation than control group and the microscopic analysis demonstrated that treated animals had better histopathologic evaluation than non treated.

Chromosomes of Crossopriza lyoni (Blackwall 1867), intraindividual numerical chromosome variation in Physocyclus globosus (Taczanowski 1874), and the distribution pattern of NORs (Araneomorphae, Haplogynae, Pholcidae)

Pholcidae (Haplogynae) encompasses 967 described species, of which only 14 have been cytogenetic analyzed. Several chromosomal features have already been described including presence of meta- and sub-metacentric chromosomes and sex determination chromosome system (SDCS) of the X, X1X2Y, and X1X2 types, which contrast with the telo- and acrocentric chromosomes and SDCS of the X1X2 type typical of entelegyne spiders. To obtain further cytogenetic information for the family, we examined two pholcid species, Crossopriza lyoni (Blackwall 1867) and Physocyclus globosus (Taczanowski 1874) using both conventional staining and silver staining techniques. Crossopriza lyoni exhibited 2n = 23 = 22 + X in males and 2n = 24 = 22 + XX in females, while P. globosus showed 2n = 15 = 14 + X and 4n = 30 = 28 + 2X, both in male adults, 2n = 16 = 14 + XX in female adults and embryos, and 2n = 15 = 14 + X in male embryos. Both species revealed predominately metacentric and submetacentric chromosomes and a SDCS of the X/XX type. The cytogenetic data obtained in this work and those already recorded for C. lyoni indicate interpopulational and intraspecific numerical chromosome variation, suggesting the presence of chromosomal races or cytotypes in this species. The intraindividual numerical chromosome variation observed in male adult specimens of P. globosus may be explained by the presence of cytoplasmatic bridges between germ cells. The use of the silver staining technique to reveal the nucleolar organizer region (NOR) showed that chromosome pairs 4 and 6 and the X chromosome in C. lyoni are telomeric NOR-bearers, and that the chromosome pair 2 in P. globosus possesses a proximal NOR in the long arm.