Morphology and Photoluminescence of HfO2 Obtained by Microwave-Hydrothermal

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Morphology and incidence of torus palatinus and mandibularis in Brazilian Indians

The incidence and morphology of torus platinus and mandibularis was verified in 200 Indians, residents of two Brazilian Indian Reserves in Sao Paulo State, Brazil. A low incidence of both types of exostoses was observed, with torus palatinus occurring more frequently than mandibularis. These structures did not occur in individuals less than 10 years of age. Flattened torus palatinus predominated in relation to the other forms.

Experimental pulmonary paracoccidioidomycosis in the Syrian hamster: morphology and correlation of lesions with the immune response.

A model for pulmonary paracoccidioidomycosis in the hamster is described. The disease was induced by intratracheal inoculation of 1.7 x 10(5) viable yeast forms of P. brasiliensis. Lung histopathology, dissemination lesions and humoral and cellular immune responses were investigated at intervals up to 24 weeks after infection. Humoral immunity was studied by immunodiffusion and complement fixation tests. Cell-mediated immunity was evaluated in vitro by the macrophage migration inhibition test in the presence of phytohaemagglutinin and P. brasiliensis soluble antigen, and in vivo by the paracoccidioidin test. Thirty out of 35 infected animals (85.7%) developed pulmonary paracoccidioidomycosis. Dissemination lesions were observed in regional lymph nodes (82.8%), liver (8.5%) and spleen (5.7%). Lung involvement was mainly around bronchi and vessels. Regional lymph nodes were severely involved from the fourth week on, acquiring a pseudotumoral aspect at later stages. Specific antibodies were detected from the fourth week on, with titres increasing progressively. The cellular immune response to phytohaemagglutinin was intact throughout the experiment and the response to P. brasiliensis antigen was already detectable by the second week and remained positive to the end of the experiment. The skin test became positive from the fourth week on. Inoculation by the intratracheal route represents a highly effective way of infecting hamsters with P. brasiliensis, with the induction of localized disease, good antibody production and intact cell immunity.

Dwarf gynes in Nannotrigona testaceicornis (Apidae, Meliponinae, Trigonini). Behaviour, exocrine gland morphology and reproductive status

The behaviour and morphology of dwarf gynes produced in worker-sized cells of normal colonies in Nannotrigona testaceicornis (Meliponinae, Trigonini) were studied. The behaviour of these dwarf virgin queens was the same as observed for normal Trigonine gynes. The glandular equipment is also the same: Dufour glands, fat bodies and spermathecae are present. Despite these similarities, their ovaries are different. The functional significance of dwarf gynes is unknown, but may be a basis for an alternative reproductive strategy.

Characterization of a monoclonal antibody recognizing mast cells

Immunohistochemical screening for monoclonal antibodies prepared by immunization of mice with a rat osteoblastic cell population led to identification of one antibody that reacted against a small population of cells present in the soft connective tissue compartment of 21 days fetal rat calvaria. The morphology of the cells and the immunohistochemical staining characteristics (a distinct intracellular granular pattern) suggested that the antibody might be reacting specifically against mast cells. We used combined histochemistry and immunohistochemistry to further characterize this antibody, designated RCJ102. Cryosections containing calvaria bone, soft connective tissues and skin were prepared from the top of the head of 21 days fetal rats, and from adult rats cryosections of lung, muscle, adipose tissue and small intestine were prepared. Some sections were labelled by indirect immunofluorescence with RCJ102; corresponding sections were labelled histochemically with toluidine blue. There was a direct correspondence between mast cells identified histochemically and cells labelling with RCJ102 in all tissues except intestine, in which the mast cell detectable by histochemistry were not labelled by RCJ102. These results suggest that the RCJ102 antibody will be a valuable new reagent for further elucidation of the heterogeneity described between connective tissue and intestinal mucosal mast cells.

Structural and surface morphology characterizations of oriented LiNbO3 thin films grown by polymeric precursor method

Polymeric precursor solution was used to deposit LiNbO3 thin films by dip coating on sapphire substrates. The effects of processing variables, such as heat treatment conditions and number of deposited layers, on crystallinity and morphology of the final films were investigated. X-ray diffraction patterns show the oriented growth of the films. The rocking curves, obtained around the (006) LiNbO3 peak, revealed that the shape peak and the FWHM value were influenced by the processing variables. According to these parameters, some films presented very homogeneous dense and smooth surfaces, as shown by the SEM and AFM studies.

Morphology of the walls of the cavernous sinus of Cebus apella (tufted capuchin monkey)

The morphology of the dura mater and its relationship with the structures of the cavernous sinus were analyzed in five tufted capuchin monkeys (Cebus apella) using histological sections, showing that the walls of the cavernous sinus of this species are similar to those of other primates, including man. Except for the medial wall of the cavernous sinus, the remaining walls consist of two distinct dura mater layers. The deep layer of the lateral wall of the cavernous sinus is contiguous to the sheath of the oculomotor, trochlear and ophthalmic nerves. Arterioles, venules, venous spaces, neuronal bodies and nervous fiber bundles are found on this lateral wall.

Atherosclerosis morphology and pathogenesis

Atherosclerosis is a very common and important disease being the most important cause of mortality in Brazil. Indeed, in 1995, 23.3% of deaths, all ages, in our country, were the consequence of atherosclerosis. This percentage grows to 26.3% for S. Paulo and 32.7% for Rio Grande do Sul. Morphologically, there are 3 main types of lesions: fatty streaks, fibrous plaques, and complicated lesions. Fatty streaks are inocuous and occur early in life. In some persons, with age, they change into fibrous plaques that may lead to stenosis. They also may become complicated by erosion, calcification, hemorrhage and thrombosis. Atherosclerosis is initiated by endothelial functional alterations responsible for increase in permeability to macromolecules, adhesion, and migration of monocytes-macrophages and lymphocytes plus recruitment of platelets and smooth-muscle medial cells. Adhesion molecules, cytokines, growth factors, and free radicals are locally synthesized, favoring proliferation of extracellular matrix and progression of the lesion. Experimental, clinical, and epidemiological evidence point to the importance of lipids, mainly cholesterol-rich low-density lipoprotein (LDL), as one of the most important molecules involved in the genesis and progression of atherosclerosis. Patients with a genetic disorder of cholesterol metabolism (familial hyperlipidemia), caused by a decrease in the availability of receptors for LDL, develop severe atherosclerosis early in life. A series of other factors, such as age, diabetes melitus, diet, hypertension, lack of exercise, elevated hemocysteinemia, immunological disorders, and coagulation instability, are related to the progression of atherosclerosis. All of them are capable of altering the endothelium or increasing the offer of LDL. All the above-mentioned factors are systemic; but atherosclerosic lesions are focal, located at preferential sites such as the emergence of colaterals, bifurcations, and curvatures of arteries, all areas in which the laminar flow is disturbed. In these areas shear stress is diminished favoring the prolongation of permanence time of lipid particles, cells, cytokines, growth factors, etc., in the vicinity of the endothelium. Moreover, the endothelium has sensors that act as transducers of mechanical forces in biological responses. Experimental data demonstrate that the number and quality of adhesion molecules, cytokines, and growth factors synthetized, as well as the local production of radicals, and pro and anticoagulation factors may change with shear stress favoring or not the local establishment and progression of atherosclerotic lesions.

Morphology of testis and epididymis in an ethanol-drinking rat strain (UChA and UChB)

The objective of the present study was to analyze the prospective alterations of the testis and epididymis in a defined strain of alcoholic rats in order to contribute to our understanding of the effects of chronic alcoholism on reproduction. The testis and epididymis of the animals were submitted to morphological analysis by macroscopy, light microscopy and electron microscopy and to morphometric analysis. The UCh rats showed atrophy of the epithelium and reduction of testis and epididymis weight, liver hypertrophy and fat infiltration and alterations of the hypothalamus-pituitary axis. Ethanol induces changes in the weight and in the epithelium of the testis and epididymis and in the hypothalamus-pituitary axis of the UCh rats.

Effect of thermal treatment on the morphology of PLZT thin films prepared from polymeric precursor method

Lead lanthanum zirconate titanate (PLZT) thin films with (9/65/35) stoichiometry were prepared by dip coating from polymeric precursor method. The films deposited on silicon (100) substrates, were thermally treated from 450° to 700°C for 6 hours in order to study the influence of thermal treatment on the crystallinity, microstructure, grain size and roughness of the final film. X-ray diffraction results showed that PLZT phase crystallizes at low temperature (500°C) and present preferential orientation. It was observed by scanning electron microscopy (SEM) that it is possible to obtain dense thin films at temperatures around 650°C. The atomic force microscopy (AFM) studies showed that the grain size and roughness are strongly influenced by the annealing temperature.

Morphology of the ventral lobe of the prostate and seminal vesicles in an ethanol-drinking strain of rats (UChA and UChB)

Chronic alcoholism alters reproduction and therefore may be responsible for alterations of prostate and seminal vesicles, which are the subject of this analysis in UCh ethanol-drinking rats. The prostate and seminal vesicles of 20 animals were submitted to macroscopic, light microscopy, electron microscopy and morphometric analysis. The UCh rats showed atrophy of the epithelium and reduction of the weight of the prostate and seminal vesicle, liver hypertrophy and fat infiltration and alterations of the hypothalamus-pituitary axis. Ethanol induces changes in the weight and in the epithelium of prostate and seminal vesicles and hypothalamus-pituitary axis of UCh rats.