Characterization of the cellular component of polymorphous low-grade adenocarcinoma by immunohistochemistry and electron microscopy

In order to characterize the cellular component of the polymorphous low-grade adenocarcinoma (PLGA) of the salivary gland, a morphological and immunohistochemical study was carried out. Thirty cases of PLGA were studied by light microscopy and immunohistochemistry and five cases by transmission electron microscopy (TEM). The expression of cytokeratins (CKs) 7,8,10,13,14,18,19, vimentin and muscle-specific actin (MSA) was investigated through the streptavidin-biotin method. The majority of tumor cells stained for vimentin, CKs 8,18 and 7. CK 14 was positive in most cells of the papillary and trabecular sub-types. Although the expression of CKs 8,18 and 14 varied among the tumors sub-types, a straight relationship between each histologic pattern and the CK expression could not be delineated. MSA was reactive in only three tumors while CKs 10 and 13 were not detected in any tumor studied. The absence of MSA and the expression of CKs 8,18 and 7, in most of the tumor cells, lead to the hypothesis that myoepithelial cells are not the major cellular component of the PLGA. TEM revealed cells exhibiting microvilli and variable amounts of secretory granules, some of them suggesting an excretory activity. The presence of CKs 8, 18 and 7, added to the secretory granules, indicates that PLGA originates from cells located at the acinar-intercalated duct junction. (C) 1999 Elsevier B.V. Ltd. All rights reserved.

Ultrastructure of the Lyonet's glands in larvae of Diatraea saccharalis Fabricius (Lepidoptera : Pyralidae)

The Lyonet's gland is found in Lepidoptera larvae, close to the excretory duct of the silk gland. The role played by this gland is still uncertain. This work aims to describe the ultrastructure of the Lyonet's bland in Diatraea saccharalis larvae, offering suggestions regarding its possible function. The insects were reared under laboratory-controlled conditions. The glands were conventionally prepared for transmission (TEM) and scanning (SEM) electron microscopy. SEM showed that Lyonet's glands are paired small structures located in the ventral side of the head. They are composed by clustered long cells resembling leaves. Under TEM observations, each cell is surrounded by a thin basal lamina and contains large stellate nucleus. The cytoplasm presents large and empty canaliculi with small microvilli. The basal plasma membrane forms numerous infoldings where numerous and well-developed mitochondria are concentrated. The cytoplasmic membrane system is poorly developed. Our ultrastructural results suggest that the Lyonet's gland in D. saccharalis larvae may be involved in the uptake of small molecules from the hemolymph no morphological evidences of macromolecules synthesis and secretion were noticed. The detection of nerve fibers in the gland suggest a neural control for the glandular cell function.

Presence of wall-devoid micro-organisms in hypopharyngeal glands of forager bees (Hymenoptera, Apidae)

The occurrence of mycoplasma-like bodies in the axial duct and intracellular canaliculli from hypopharyngeal glands of bees (Meliponinae and Apinae) is described. Since they are not found within cells and due to the absence of cellular alterations in the infected glands it is suggested that micro-organisms are not pathogenic to the bees.

Liver lesions produced by aflatoxins in Rana catesbeiana (bullfrog)

This study describes alterations induced in Rana catesbeiana (bullfrog) liver after extended dietary exposure to aflatoxins (AFs). Bullfrogs of both sexes were fed for 120 days a commercial chow blended with a rice bran-based mixture of Al's containing 667.0, 11.65, 141.74, and 3.53 mg/kg of AFs B1, B2, G1, and G2, respectively. Animals were sacrificed on study days 45, 90, and 120. Severe and progressive liver lesions with structural collapse, increased hepatocyte and biliary duct cell proliferation, appearance of basophilic hepatocytes, and diffuse scarring, were observed at all time points. There were no quantitative alterations in the liver melanomacrophage centers of the AFs-exposed animals. Increased amounts of lipid hydroperoxides, indicative of ongoing oxidative stress, were more evident in the Addutor magnum muscle than in the AFs-damaged livers. No tumors were found in the R. catesbeiana livers after 120 days of exposure to relatively high doses of AFs. (c) 2006 Elsevier B.V. All rights reserved.

SCANNING ELECTRON-MICROSCOPY OF THE RHODNIUS-NEGLECTUS (HEMIPTERA) LABIAL SALIVARY-GLANDS AFTER STARVATION

Labial salivary glands are found in the majority of insects. They are relatively large, extend back into the thorax, and in Rhodnius, they are cherry red in color due to a pigment derived from traces of hemoglobin absorbed form the gut. In most insects they are acinous shaped, with long excretion channels that present differentiated regions which from salivary reservoirs. The glands may be relatively simple or complexly branched and convoluted. In Rhodnius they are described as being unilobed with no traces of division. The main duct leaves the gland at its anterior extremity. The acini have different kinds of cells but all of them are seen as sources of secretion. Our material has a different shape due to the fact that the animals spent 20 days under starvation conditions. New data are also obtained through treatment with collagenase and HCl. The importance of the study of these glands lies in the fact that it will further understanding of the transmission of Chagas' disease.

Nonlinear parameter estimation in laminar forced convection within a circular sector tube

In this article we examine an inverse heat convection problem of estimating unknown parameters of a parameterized variable boundary heat flux. The physical problem is a hydrodynamically developed, thermally developing, three-dimensional steady state laminar flow of a Newtonian fluid inside a circular sector duct, insulated in the flat walls and subject to unknown wall heat flux at the curved wall. Results are presented for polynomial and sinusoidal trial functions, and the unknown parameters as well as surface heat fluxes are determined. Depending on the nature of the flow, on the position of experimental points the inverse problem sometimes could not be solved. Therefore, an identification condition is defined to specify a condition under which the inverse problem can be solved. Once the parameters have been computed it is possible to obtain the statistical significance of the inverse problem solution. Therefore, approximate confidence bounds based on standard statistical linear procedure, for the estimated parameters, are analyzed and presented.

Estudo experimental sobre a intoxicação de Gallus gallus domesticus com semente de crotalaria spectabilis. II efeito em aves na fase final de crescimento

This study was undertaken to investigate the toxic effect of Crotalaria spectabilis seeds added to the ration for commercial broilers during the final phase of growth. Ground seeds were added at different concentrations to the ration: 0.0% (control), 0.01%, 0.1% and 0.4%. Rations containing 0.4% caused symptoms of intoxication, beginning in the second week of the study. During the third week birds showed bristling, apathy, general weakness, distended abdomen and agglomeration. In the fourth week, four animals died. Necropsy revealed prominent ascites and severe lesions of liver, kidney and lung. Microscopic examination revealed necrosis of hepatocytes, inflammatory cell infiltration, hypertrophy and hyperplasia of biliary duct cells leading to atresia and cholestasis. Prominent cartilaginous and osseous nodules in the lungs were also present as well as degenerative, changes in the kidney tubules and necrosis of cells of the bursa. All the broilers receiving a ration with 0.1% of Crotalaria seeds showed ascites and slight lesions of the liver. The remaining groups showed no reduction in weight gains, lesions or clinical symptoms. It is concluded that broilers during the final phase of growth are sensitive to administrations of seeds of C. spectabilis in their ration. The presence of ascites and cartilaginous and osseous nodules in the lungs of the affected birds was also considered important.

Is oral nutritional therapy effective for the treatment of chylothorax? A case report

We report a case of a female patient who underwent corrective aortic coarctation surgery that progressed to chylothorax on the fifth postoperative day. Because the patient was clinically stable and had a functioning digestive tract, the nutritional team decided to treat her by oral nutritional support with a low-lipid diet, rich in medium-chain triacylglycerols. After 20 d, the patient returned to her habitual home diet and did not develop pleural spilling, showing full healing of the thoracic duct. (C) 2008 Elsevier B.V. All rights reserved.

Morfologia do figado da paca (Cuniculus Paca, Linnaeus 1766)

The elements related to the morphology of the liver of paca (Cuniculus paca), the second largest rodent of the Brazilian fauna, were observed; this species present zootechnical potential. Eight animals from the animals sector of Faculdade de Ciencias Agrarias e Veterinarias - Campus of Jaboticabal - UNESP, which is duly certified by IBAMA as an experimental breeding institute, were used. Through a dissection procedure, it was found that the liver of the paca is located in the cranial portion of the abdomen, immediately after the diaphragm, to which it is connected by the triangular, coronary, and falciform ligaments, having its bigger part located right to the medium plan. The liver of this rodent presents the following lobation: right lateral lobe, right medial lobe, quadrate lobe, left medial lobe, and left lateral lobe, besides the caudate lobe formed by the papillary process of caudate lobe and the caudate process of caudate lobe. Gallbladder is located between the quadrate and right medial lobes. Fragments of this organ were collected, fixed, and histologically prepared, being the samples analyzed through light microscopy. It was microscopically observed that intralobular connective tissue is scarce, basically it consists polyhedral hepatocytes organized into cords interposed between sinusoids and the portal triads are found in the lobe, consisting of the portal vein, hepatic artery, and biliary duct.

Choledochal cyst: A case associated with traumatic hemobilia

A case of choledochal cyst associated with traumatic hemobilia is presented. The symptomatology appeared only because of bleeding into the biliary tract following an automobile accident. The cyst was resected and a choledochal cystoduodenum anastomosis performed. The early result (12 mth) was very good.

The fine structure of the swine sweat gland. II. The coiled ducts

The duct of the swine sweat gland crosses the dermis and epidermis in sequence. The cells of the dermic segment seem to be related with cellular secretion and absorption. In the epidermic segment of the duct the whole morphology of the cells resembles the cellular morphology of the epidermic cells.

Detection of estrogen receptor in formalin-fixed and paraffin-embedded breast carcinoma: correlation with histological patterns.

The authors studied the expression of estrogen receptor (ER) in tissues of breast carcinomas which were previously fixed in formalin and paraffin-embedded. The ER expression was correlated with several histological findings, namely grade of differentiation, tumor necrosis, desmoplasia, lymphocytic infiltration and elastosis. The ER was detected in tissues using the avidin-biotin immunoperoxidase technique associated with the H222 monoclonal antibody from Abbott. All 39 biopsies were of infiltrating ductal carcinoma of breast and 16 of them expressed ER. The statistical analysis showed that the expression of ER was correlated with histological findings of good prognosis as well differentiated carcinomas, no tumor necrosis, absence or mild lymphocytic infiltration around the tumor cells and severe elastosis.

Two thermal methods to measure the energy fluence of a brief exposure of diagnostic x rays

This paper describes two simple thermal methods for measuring the energy fluence in J/cm 2 from a diagnostic x-ray exposure. Both detectors absorb essentially 100% of the radiation and give a signal that is directly proportional to the energy fluence of the x-ray beam. One detector measures the thermal effect when a pulse of x rays is totally absorbed in the pyroelectric detector of lead-zirconium-titanate (PZT). The other detector measures the expansion of a gas surrounding a lead disk detector in a photoacoustic chamber. The increased pressure of the gas is transmitted through a 1-mm duct to a sensitive microphone. Both detectors have previously been used to measure the energy fluence rate of continuous x-ray beams in the same energy region using a chopped beam and a lock-in amplifier. Measurement of the energy fluence of a pulse of radiation eliminates the need for the beam chopper and lock-in amplifier and results in a simple, rugged, and inexpensive dosimeter. Either method can be combined with the area of the beam to give an estimate of the imparted energy to the patient from a diagnostic x-ray exposure.