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1.
Braz J Med Biol Res ; 51(3): e6329, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29513879

ABSTRACT

Recent evidence shows that chronic ethanol consumption increases endothelin (ET)-1 induced sustained contraction of trabecular smooth muscle cells of the corpora cavernosa in corpus cavernosum of rats by a mechanism that involves increased expression of ETA and ETB receptors. Our goal was to evaluate the effects of alcohol and diabetes and their relationship to miRNA-155, miRNA-199 and endothelin receptors in the corpus cavernosum and blood of rats submitted to the experimental model of diabetes mellitus and chronic alcoholism. Forty-eight male Wistar rats were divided into four groups: control (C), alcoholic (A), diabetic (D), and alcoholic-diabetic (AD). Samples of the corpus cavernosum were prepared to study the protein expression of endothelin receptors by immunohistochemistry and expression of miRNAs-155 and -199 in serum and the cavernous tissue. Immunostaining for endothelin receptors was markedly higher in the A, D, and AD groups than in the C group. Moreover, a significant hypoexpression of the miRNA-199 in the corpus cavernosum tissue from the AD group was observed, compared to the C group. When analyzing the microRNA profile in blood, a significant hypoexpression of miRNA-155 in the AD group was observed compared to the C group. The miRNA-199 analysis demonstrated significant hypoexpression in D and AD groups compared to the C group. Our findings in corpus cavernosum showed downregulated miRNA-155 and miRNA-199 levels associated with upregulated protein expression and unaltered mRNA expression of ET receptors suggesting decreased ET receptor turnover, which can contribute to erectile dysfunction in diabetic rats exposed to high alcohol levels.


Subject(s)
Alcoholism/metabolism , Diabetes Mellitus, Experimental/metabolism , Endothelin-1/analysis , MicroRNAs/analysis , Penis/metabolism , Receptor, Endothelin A/analysis , Receptor, Endothelin B/analysis , Alcoholism/complications , Alcoholism/physiopathology , Animals , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/physiopathology , Immunohistochemistry , Male , Penis/physiopathology , Rats , Rats, Wistar
2.
Int. j. morphol ; 32(2): 614-617, jun. 2014. ilus
Article in English | LILACS | ID: lil-714318

ABSTRACT

The rat is probably the most commonly used animal in scientific research. There are many benefits to its use such as: ability to work a large number of animals allowing greater statistical validity, the relatively short life cycles. However, the scant literature regarding the anatomy and morphology of these animals is also old and not very descriptive. The objective of this research is to study the macroscopic morphometric aspects of several parameters that have not been described yet regarding the heart of Wistar rats in different phases of their lives. Thirty-six adult male and female rats (Rattus norvegicus) weighting 150-770 g were randomly divided into 6 experimental groups. The heart was then carefully dissected and removed from the chest. After this process, the heart had their weight measured on a precision scale HELMAC HM100, and for each front section of the heart related measures were taken through a semi-automatic image analysis of Kontron Build Analyse (Minimop). The percentage ratio between the relative heart weight to body weight was between 0.5 and 0.7% in the animals with body weight up to 650 g. The maximum and minimum diameters were always statistically lower in females compared to males. The measurements showed the hearts of the females shorter, narrower, smaller and lighter than those of males. Over the life of these females, although the heart weight increases, the heart apparently keeps its shape and size. Furthermore, the hearts of males narrow and stretch along their development.


La rata es probablemente el animal más utilizado en investigaciones científicas. Hay muchos beneficios por su uso como la capacidad de trabajar con un gran número de animales permitiendo una mayor validez del punto de vista estadístico o el ciclo de vida relativamente corto del animal. Sin embargo, la escasa literatura sobre la anatomía y la morfología de la rata es antigua y no muy descriptiva. El objetivo de esta investigación fue estudiar parámetros morfométricos macroscópico no descritos con respecto al corazón de la rata Wistar en diferentes fases de la vida. Treinta y seis ratas (Rattus norvegicus) adultas, hembras y machos pesando entre 150­770 g, fueron divididas al azar en 6 grupos diferentes. El corazón fue cuidadosamente disecado y retirado del tórax. Cada corazón fue pesado en una balanza de precisión y para cada sección frontal del corazón fueron tomadas medidas relativas mediante un análisis de imágen semi-automático Kontron Build Analyse (Minimop). El porcentaje de proporción entre el peso relativo del corazón y el peso del cuerpo fue entre 0,5­0,7% en animales con peso corporal de hasta 650 g. Los diámetros máximos y mínimos fueron estadísticamente menores en hembras comparádolos con machos. Las medidas mostraron que los corazones en las hembras son más cortos, angostos, pequeños y livianos que en machos. Durante la vida de estas hembras, aunque el peso del corazón aumenta, aparentemente mantiene su forma y su tamaño. Por otro lado, los corazones de los machos se estiran y se estrechan durante su desarrollo.


Subject(s)
Animals , Male , Female , Rats , Heart/anatomy & histology , Organ Size , Body Weight , Sex Characteristics , Rats, Wistar , Heart/growth & development
3.
Article in English | MEDLINE | ID: mdl-24730960

ABSTRACT

The metric signature topological transitions associated with the propagation of electromagnetic waves in a dispersive metamaterial with frequency-dependent and anisotropic dielectric and magnetic responses are examined in the present work. The components of the reciprocal-space metric tensor depend upon both the electric permittivity and magnetic permeability of the metamaterial, which are taken as Drude-like dispersive models. A thorough study of the frequency dependence of the metric tensor is presented which leads to the possibility of topological transitions of the isofrequency surface determining the wave dynamics inside the medium, to a diverging photonic density of states at some range of frequencies, and to the existence of large wave vectors' modes propagating through the metamaterial.

4.
Genet Mol Res ; 12(2): 878-86, 2013 Apr 02.
Article in English | MEDLINE | ID: mdl-23613234

ABSTRACT

We examined the expression of anti-apoptotic genes (XIAP and Bcl-2) and apoptotic genes (cytochrome c, caspase-9, Apaf-1) in tissue samples of patients with superficial bladder cancer. Thirty-two bladder cancer tissue samples (8 papillary urothelial neoplasm of low malignant potential, 10 low-grade, and 14 high-grade) and 8 normal bladder tissue samples from necropsy were used for the study of gene expression by real-time PCR analysis. Analysis of the expression of apoptotic gene constituents of an apoptosome demonstrated an increase in Apaf-1 expression in the three tumor grades when compared with the control (P < 0.01, P < 0.05, and P < 0.01), low expression of caspase-9 in all groups (P < 0.05), and an increase in cytochrome c expression in all tumor grades in relation to the control, although without statistically significant difference. The expression of anti-apoptotic genes revealed an increase in XIAP expression in all tumor grades in relation to the control, although without statistically significant difference, and low expression of Bcl-2 in all tumor grades and the control (P < 0.05). The results proved that there is low evidence of apoptotic activity by the intrinsic pathway, demonstrated by the low expression of caspase-9 and considerable increase in XIAP expression, which may render these genes potential therapeutic targets in bladder cancer treatment.


Subject(s)
Apoptosis/genetics , Gene Expression Regulation, Neoplastic , Signal Transduction , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/metabolism , Apoptotic Protease-Activating Factor 1/genetics , Apoptotic Protease-Activating Factor 1/metabolism , Caspase 9/genetics , Caspase 9/metabolism , Cytochromes c/genetics , Cytochromes c/metabolism , Gene Expression Profiling , Humans , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Real-Time Polymerase Chain Reaction
5.
Eur J Vasc Endovasc Surg ; 45(5): 465-7, 2013 May.
Article in English | MEDLINE | ID: mdl-23473782

ABSTRACT

INTRODUCTION: We report a case of an emergency high-risk patient with a pararenal aortic aneurysm. REPORT: Our patient had a pararenal aneurysm with two components: a wide-neck saccular aneurysm below the left renal artery and a fusiform aneurysm. A self-expandable aortic stent was deployed covering both renal arteries, the saccular aneurysm was embolised with microcoils and a bifurcated aortic endograft was anchored inside the aortic stent. The aortic stent imprisoned the microcoils and avoided proximal type I endoleak. The tomography done 15 months after the procedure showed no endoleaks. DISCUSSION: A self-expandable aortic stent can provide an alternative for emergency high-risk patients with pararenal aortic aneurysms.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Endovascular Procedures/instrumentation , Stents , Aged , Humans , Kidney , Male , Prosthesis Design
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(4 Pt 2): 047601, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20481864

ABSTRACT

We discuss the propagation of electromagnetic waves in layered structures made up of alternate layers of air and metamaterials. The role played by absorption on the existence of electric and magnetic plasmon polaritons is investigated. Results show that plasmon-polariton modes are robust even in the presence of rather large absorption.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(1 Pt 1): 011103, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20365319

ABSTRACT

We present a unified formulation for quantum statistical physics based on the representation of the density matrix as a functional integral. For quantum statistical (thermal) field theory, the stochastic variable of the statistical theory is a boundary field configuration. We explore the properties of an effective theory for such boundary configurations and apply it to the computation of the partition function of an interacting one-dimensional quantum-mechanical system at finite temperature. Plots of free energy and specific heat show excellent agreement with more involved semiclassical results. The method of calculation provides an alternative to the usual sum over periodic trajectories: it sums over paths with coincident end points and includes nonvanishing boundary terms. An appropriately modified expansion into modified Matsubara modes is presented.

8.
J Phys Condens Matter ; 22(38): 385901, 2010 Sep 29.
Article in English | MEDLINE | ID: mdl-21386558

ABSTRACT

Absorption effects on plasmon-polariton excitations in quasiperiodic (Fibonacci and Thue-Morse) one-dimensional stacks composed of layers of right- and left-handed materials are theoretically investigated. A Drude-type dispersive response for both the dielectric permittivity and magnetic permeability of the left-handed layer is considered. Maxwell's equations are solved for oblique incidence by using the transfer matrix formalism, and the reflection coefficient as a function of the frequency and incidence angle is obtained. The Fibonacci (or Thue-Morse) quasiperiodic structure leads to a Cantor-like photonic spectra for the plasmon-polariton modes. Moreover, results for the photonic band structure, density of states and reflection coefficient indicate that plasmon-polariton modes are robust in the presence of low and moderate levels of absorption.

9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(5 Pt 2): 056112, 2002 May.
Article in English | MEDLINE | ID: mdl-12059652

ABSTRACT

We present a simple method to deal with caustics in the semiclassical approximation to the thermal density matrix of a particle moving on the line. For simplicity, only its diagonal elements are considered. The only ingredient we require is the knowledge of the extrema of the Euclidean action. The procedure makes use of complex trajectories, and is applied to the quartic double-well potential.

10.
Rev Hosp Clin Fac Med Sao Paulo ; 53(2): 55-60, 1998.
Article in English | MEDLINE | ID: mdl-9699355

ABSTRACT

We have examined the sizes of nerve cells present in the myenteric plexus in the human esophagus, stomach, duodenum and sigmoid colon using a nonhistochemical method (Giemsa) in laminar preparations of the muscularis externa. The collagen and elastic system related fibers in the myenteric ganglia were also qualitatively evaluated. The major mean of perikaryal area was observed in the esophagus (489.97 micron 2 +/- 212.35 micron 2) and the minor in the sigmoid colon (241.64 micron 2 +/- 122.62 micron 2). There were no significant differences between the mean areas of the myenteric neurons in the stomach (284.77 micron 2 +/- 134.70 micron 2) and in the duodenum (291.39 micron 2 +/- 157.86 micron 2). In all regions a ganglionic capsule of collagen fibers with thin septa surrounding isolated or grouped neurons was observed. The elastic and elastic-related fibers (elaunin and oxytalan fibers) were also present in both the ganglionic capsule and inside the ganglia. There were no differences among the regions. These data suggest that factors such as size of nerve cells and structural aspects of the ganglionic capsule are not related with the incidence of megaesophagus and megacolon.


Subject(s)
Digestive System/innervation , Myenteric Plexus/cytology , Neurons/cytology , Adult , Analysis of Variance , Azure Stains , Cadaver , Cell Size , Collagen , Elastic Tissue/cytology , Female , Humans , Male
11.
Surg Radiol Anat ; 20(1): 13-21, 1998.
Article in English | MEDLINE | ID: mdl-9574484

ABSTRACT

The arrangement of collagen and elastic fibers of the membranous part of the interventricular septum (PMS) was studied in hearts from adult humans. Connective bundles formed a network of fairly independent tendons arranged in two layers. The tendinous bundles consisted essentially of type I collagen fibers while type III fibers were visible as a thin network with transversely and longitudinally oriented meshes around the muscle bundles. Cranial and caudal to the PMS were narrow and irregular bands of collagen fibers that apparently represented zones of low resistance to the high blood pressures acting from the left to the right heart chambers. The predominance of fiber bundles arranged in an approximately transverse direction with regard to the arterial cone axis suggests a resistance to enlargement resulting from high aortic blood pressure. Elastic fibers were observed in the transitional zone between the cardiac muscle and the PMS. They were continuous with elaunin fibers and these with oxytalan fibers closely intermingled with the narrow network of type I collagen fibers of the PMS. The successive transformation of elastic fibers, which were very numerous in the muscle-tendon transition, into elaunin and these into oxytalan fibers toward the central portions of the PMS suggests a functional sequence characterized by a high elasticity and consequent mobility of the transition region itself and by a progressive increase of resistance in this portion.


Subject(s)
Heart/anatomy & histology , Adult , Aged , Cadaver , Collagen/ultrastructure , Elastic Tissue/anatomy & histology , Elastic Tissue/ultrastructure , Heart Septum/anatomy & histology , Heart Septum/ultrastructure , Heart Ventricles/anatomy & histology , Humans , Microscopy, Electron, Scanning , Microscopy, Polarization , Middle Aged
12.
Braz J Med Biol Res ; 29(3): 363-5, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8736131

ABSTRACT

We determined the effect of dietary sodium intake (0.15 and 8% NaCl) on the cardiac neuron size of normotensive 3-week old Wistar rats. An increase in dietary sodium for 48 weeks induced an increase in neuronal size. The number of large neurons (larger than 500 microns 2) increased significantly (chi-square test) in rats ingesting 8% NaCl in their food. The rats presented hypertension (128 +/- 9 vs 134 +/- 16 mmHg; difference not significant, Student t-test) and a statistically significant increase in cardiac muscle mass (1.6 +/- 0.1 vs 2.0 +/- 0.2 mg/g of rat). We conclude that food sodium can significantly increase cardiac nerve cell size and this trophic response occurs concomitantly with an increase of cardiac muscle mass.


Subject(s)
Cardiomegaly/physiopathology , Hypertension/chemically induced , Neurons/drug effects , Sodium, Dietary/pharmacology , Animals , Cardiomegaly/etiology , Chi-Square Distribution , Hypertension/etiology , Myocardium/pathology , Neurons/physiology , Rats , Rats, Wistar
13.
Braz. j. med. biol. res ; 29(3): 363-5, Mar. 1996. ilus, graf
Article in English | LILACS | ID: lil-163845

ABSTRACT

We determined the effect of dietary sodium intake (0.15 and 8 per cent NACl) on the cardiac neuron size of normotensive 3-week old Wistar rats. An increase in dietary sodium for 48 weeks induced an increase in neuronal size. The number of large neurons (larger than 500 muM2) increased significantly (chi-square test) in rats ingesting 8 per cent NaCl in their food. The rats presented hypertension (128 ñ 9 vs 134 ñ 16 mmHg; difference not significant, Student t-test) and a statistically significant increase in cardiac muscle mass (1.6 ñ 0.1 vs 2.0 ñ 0.2 mg/g of rat). We conclude that food sodium can significantly increase cardiac nerve cell size and this trophic response occurs concomitantly with an increase of cardiac muscle mass.


Subject(s)
Animals , Rats , Hypertension/chemically induced , Cardiomegaly/physiopathology , Neurons , Sodium, Dietary/pharmacology , Hypertension/etiology , Cardiomegaly/etiology , Myocardium/pathology , Neurons/physiology , Rats, Wistar
14.
Acta Anat (Basel) ; 156(1): 53-60, 1996.
Article in English | MEDLINE | ID: mdl-8960299

ABSTRACT

The cardiac plexus of the Wistar rat was investigated in whole-mount preparations of the atria by NADH-diaphorase staining and by the acetylcholinesterase (AChE) histochemical technique. The plexus lies over the muscular layer of the atria, dorsal to the muscle itself, in the connective tissue of the subepicardium. The plexus contains on average 975 +/- 150 neurons, occurring singly or gathered in packed ganglia. The ganglia are found regularly in certain situations, namely, cranially to the pulmonary veins (44% of total); cranially and to the left of superior vena cava (10%); in the interatrial groove (21%); to the left of the left pulmonary vein (11%); caudally to the pulmonary veins (12%) and in the wall of the coronary sinus (1%). Ganglia are never found on the auricular appendages. For the histochemical demonstration of AChE, the 'direct coloring' copper ferrocyanide method was used. Extrinsic nerves enter the atria along the superior vena cava, along the pulmonary veins and along the coronary sinus, forming ganglion-containing plexuses. From specific sites of these plexuses, nerves proceed to the ganglia located to the left of the superior vena cava, to the ventral and dorsal ventricular wall and to the wall of the right atrium, where they form a delicate plexus accompanying the muscle fibers. Most of the neurons of the plexuses displayed AChE activity in the cytoplasm though they presented different reaction intensities. The distribution of cardiac nerves from groups of neurons located at discrete sites may indicate that postganglionic nerves selectively project to and thus control specific cardiac regions and/or functions.


Subject(s)
Ganglia/anatomy & histology , Heart/innervation , Nerve Fibers/ultrastructure , Acetylcholinesterase , Animals , Female , Image Processing, Computer-Assisted , Male , Rats , Rats, Wistar , Staining and Labeling
15.
Clin Anat ; 9(1): 34-40, 1996.
Article in English | MEDLINE | ID: mdl-8838278

ABSTRACT

The arrangement of the smooth muscle and elastic and collagen fibers of the minor papilla of the human duodenum was studied on 53 duodenopancreatic specimens obtained from adults of both sexes. Methods included stereological analyses of gross anatomical specimens and thick and thin microscopic sections. The muscular and elastic fibers of the minor papilla have a unidirectional arrangement by which the contraction of its smooth muscular fibers causes opening of its orifice allowing the flow of the pancreatic juice into the duodenum. It is not a typical anatomical sphincter.


Subject(s)
Duodenum/anatomy & histology , Pancreatic Ducts/anatomy & histology , Adolescent , Adult , Aged , Aged, 80 and over , Collagen , Elastic Tissue , Female , Humans , Male , Middle Aged , Models, Biological , Muscle, Smooth/anatomy & histology , Pancreatic Juice/physiology
16.
Gerontology ; 42(4): 211-7, 1996.
Article in English | MEDLINE | ID: mdl-8832269

ABSTRACT

The effects of age on the human heart elastic fibers were studied by light and electron microscopy. Studies were done on 15 hearts from male subjects 42 days to 87 years of age. Using specific staining procedures, the length of elastic fibers was determined by morphometry in the parenchyma of right and left ventricles. These studies suggest that the length of elastic fibers per unit heart volume is present early in life, possibly at birth, and thereafter remains constant until adulthood. Average fiber length increases significantly beyond the third decade of life which can be interpreted as a continuous formation of new fibers and a continuous apposition of elastic-type material to these fibers. Electron microscopy confirmed the presence of mature elastic fibers at birth, since they contained amorphous substance (elastin) surrounded by numerous microfibrils. In the adult hearts, the amount of amorphous substance has increased and the number of microfibrils has decreased. With advancing age the amorphous substance forms areas of rarefaction and the microfibrils have disappeared. Whether or not such morphometric modifications could influence the elastic properties of the ventricular myocardium requires further study.


Subject(s)
Aging , Elastic Tissue/ultrastructure , Myocardium/ultrastructure , Adult , Aged , Child, Preschool , Humans , Infant , Male , Microscopy, Electron
18.
Clin Anat ; 8(2): 102-9, 1995.
Article in English | MEDLINE | ID: mdl-7712319

ABSTRACT

The morpho-functional relationships between the hepato-duodenal ligament and the superior part of the duodenum are analysed. Twenty-four specimens were removed during necropsies of adults and prepared according to various mesoscopic, microscopic, and ultramicroscopical methods, i.e., whole-mounts, membrane preparations, thick and thin histological sections, and polarized light, scanning, and transmission electron microscopy were employed. The hepato-duodenal ligament is formed by longitudinally elongated, type I collagen fiber bundles which are interlinked by more delicate bundles of type III collagen fibers. Longitudinally disposed elastic fibers are the principal component of the elastic fiber system of the ligament. These are in continuity with the elaunin and oxytalan fibers which are intermingled with the muscle cells of the vessels and duodenal wall, and fat cells of the ligament. Part of the muscle bundles of the external, longitudinal, muscle layer of the duodenum is anchored in the adventitial and subserosal collagen and elastic fiber framework of the organ while part inserts directly into the fibrous framework of the ligament. The fibrous system of the ligament is continuous with that of the subserosa and adventitia of the duodenum.


Subject(s)
Duodenum/anatomy & histology , Ligaments/anatomy & histology , Liver/anatomy & histology , Cadaver , Duodenum/physiology , Humans , Ligaments/ultrastructure , Liver/physiology , Microscopy, Electron
19.
Rev Hosp Clin Fac Med Sao Paulo ; 49(2): 49-52, 1994.
Article in English | MEDLINE | ID: mdl-7817091

ABSTRACT

Cast of the mucosal and submucosal veins of the esophago-gastric junction were studied in five necropsy specimens by scanning electron microscopy to analyse some of the characteristics of their shape and surface. Two types of veins were described: 1) veins with circumscript, fusiform and/or ampullar bulges and relatively smooth surfaces; 2) veins with numerous, small bulges and blister-shaped micro-dilatations. The role of these features is considered in the formation of esophageal varices.


Subject(s)
Esophagogastric Junction/blood supply , Adult , Female , Humans , Male , Microscopy, Electron, Scanning , Veins/ultrastructure
20.
Surg Radiol Anat ; 16(3): 267-75, 1994.
Article in English | MEDLINE | ID: mdl-7863412

ABSTRACT

The arrangement of muscle, collagen and elastic fibers was studied in the retro- and suprahepatic (subdiaphragmatic) portions of the inferior vena cava, the hepatic veins and their main affluents. Distinctive features of the longitudinal and transverse muscle bundles are described. In these portions of the vena cava, both bundle systems are clearly separate and any continuity was observed only at the entrances of the hepatic veins. A musculo-venulolymphatic complex was noted in spurs formed by the vascular junctions. The hepatic veins and their main affluents exhibit an elliptical contour in transverse section, which apparently results from cranial and caudal thickenings of the longitudinal muscle layer. Many of these bundles are in continuity with those of the transverse muscle layer. Terminal elastic tendons were rarely observed in connection with muscle fibers of the inferior vena cava and are not present in the hepatic veins and their main affluents. In terms of form and function, the relatively thin muscular layer has a dilating action on the hepatic venous system because of the external fixed insertion point of the muscle bundles. Such an arrangement and a "polar" disposition of the muscle bundles in the hepatic venous system may assists in "suction" of the blood toward the heart. A sphincteric control of the ostia by means of crossed muscular loops supported by venulo-lymphatic micropads is a possibility.


Subject(s)
Hepatic Veins/anatomy & histology , Vena Cava, Inferior/anatomy & histology , Collagen/ultrastructure , Humans , Liver Circulation/physiology , Muscle, Smooth, Vascular/cytology
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