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1.
Z Mikrosk Anat Forsch ; 104(4): 578-92, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2077761

RESUMO

Ultrastructure and histochemistry of clinically normal appearing tissue and secretions of non-lactating human mammary glands have been investigated in order to document and analyse secretory phenomena in the resting gland. The material studied originated from women of different ages (18-74 years) who underwent plastic surgery or surgery for various disorders of the breast. The epithelia of small ducts and of alveolar enlargements as well as acini contained moderate amounts of mitochondria and of cisterns of the rough endoplasmic reticulum; the transcisterns of the Golgi apparatus which were surrounded by smooth and coated vesicles, exhibited modest dilatations, the number of lysosomes increased with age; regularly glycogen particles and bundles of intracellular filaments (phi 5 nm) were to be observed. Typical casein vesicles and stages of apocrine secretion of milk fat globules were not seen. The following features indicated secretory activity: differently sized vesicles and granules with flocculent, dense, or light contents were regularly to be seen in the apical cytoplasm often immediately below the apical plasma membrane of the epithelia of the small ducts and even more frequently in the alveolar enlargements. Secretory products of fine granular or filamentous structure, probably containing proteins, were frequently found within the lumen. Different types of lipid and liposome-like particles were detected both in intracellular localization as well as in ductal lumina. As demonstrated by lectin histochemistry the secretory products also contained a considerable amount of carbohydrate components. The composition of the secretory products of the resting gland is of clinical interest since the chronical deposition of secretions, which among others possibly contain enzymes producing oxygen radicals, may lead to pathological changes of mammary gland tissue.


Assuntos
Mama/metabolismo , Adulto , Fatores Etários , Idoso , Mama/ultraestrutura , Feminino , Histocitoquímica , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade
2.
Acta Histochem Suppl ; 40: 59-64, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2091048

RESUMO

A specific secretory product of the lactating mammary gland are triglyceride fat globules which are enveloped by a very complex membrane, the milk fat globule membrane (MFGM). In different mammalian species (man, rhesus monkey, horse, goat, sheep, cow, grey seal, camel, alpaka) the glycoproteins of this membrane have been analyzed by gel electrophoresis, Western blotting and lectin histochemistry. A remarkable intra- and interspecific variability of these glycoproteins has been detected pointing to so far unknown physiological adaptions, which may play a role in the intestine of the new born. High molecular weight glycoproteins, with a very high degree of glycosilation have been found only in primates, horse and camel; the MFGMs of the true ruminants (cow, sheep, goat) are characterized by specific glycoproteins of a lower molecular weight range.


Assuntos
Glicoproteínas de Membrana/metabolismo , Leite Humano/metabolismo , Leite/metabolismo , Animais , Western Blotting , Camelídeos Americanos , Camelus , Bovinos , Eletroforese em Gel de Poliacrilamida , Feminino , Cabras , Histocitoquímica , Cavalos , Humanos , Lectinas , Macaca mulatta , Mucina-1 , Focas Verdadeiras , Ovinos
3.
Atherosclerosis ; 80(2): 149-57, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2692572

RESUMO

The Simpson atherectomy device used for the recanalization of severely stenosed peripheral arteries is able to collect plaque material which can be further characterized. This study reports histological, immunohistochemical and transmission electron microscopic findings on advanced human primary atherosclerotic plaques of peripheral arteries percutaneously removed by a Simpson atherectomy catheter. Material from stenosing plaques consisted of dense connective tissue with abundant amounts of concentrically arranged elastic fibers and lamellae. This meshwork contained numerous cells, often arranged in clusters and oriented with their longer axis parallel to the direction of blood flow. The vast majority of these cells could be easily identified as vimentin-positive and desmin-negative smooth muscle cells containing lipid deposits in the perinuclear region and numerous glycogen particles. Monocytes/macrophages were observed only very infrequently. Plaque tissue contained a range of smooth muscle cell phenotypes. Most of the cells were of an intermediate phenotype, i.e. sparsely filled with myofilament bundles at the cell periphery and a high amount of organelles such as mitochondria, rough endoplasmic reticulum and Golgi cisterns. An intact lining of pieces of intimal tissue with endothelial cells was not observed. Two-dimensional gel electrophoresis of plaque tissue showed the presence of alpha-, beta- and gamma-actin isoforms with a clear predominance of the beta-isoform.


Assuntos
Arteriosclerose/patologia , Músculo Liso Vascular/patologia , Arteriosclerose/metabolismo , Eletroforese em Gel Bidimensional , Artéria Femoral/patologia , Imunofluorescência , Humanos , Artéria Ilíaca/patologia , Microscopia Eletrônica , Músculo Liso Vascular/análise , Artéria Poplítea/patologia
5.
Laryngol Rhinol Otol (Stuttg) ; 67(9): 469-74, 1988 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-3172945

RESUMO

Despite a twofold recloning, ultrastructural analysis of squamous cell carcinoma lines of the head and neck showed morphologically a very heterogeneous picture in respect of the cytoplasmatic organelles, electron density of the cytoplasma, nucleus and differentiation of the cell membranes. Most prominent were the differences in the content of mitochondria and the formation of intracytoplasmatic filaments and desmosomes. Although the cells have been cultured as single cells, they developed desmosomes in vitro. The cell contact formation varied to such a degree that the plasma membranes of the cells from the tongue squamous cell carcinoma line SCC-25, as an example, were almost completely occupied by desmosomes.


Assuntos
Carcinoma de Células Escamosas/ultraestrutura , Neoplasias de Cabeça e Pescoço/ultraestrutura , Células Tumorais Cultivadas/ultraestrutura , Linhagem Celular , Humanos , Neoplasias Hipofaríngeas/ultraestrutura , Neoplasias Laríngeas/ultraestrutura , Microscopia Eletrônica , Organelas/ultraestrutura , Neoplasias Parotídeas/ultraestrutura , Neoplasias da Língua/ultraestrutura
6.
Laryngol Rhinol Otol (Stuttg) ; 67(8): 416-9, 1988 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-3210876

RESUMO

Annulate lamellae have been described in rapidly dividing and proliferating cells as germ cells of invertebrates and vertebrates and in some neoplastic cells. Although their functional significance is still unknown, it is postulated that these organelles play a central role in cell growth and differentiation. In the present study, annulate lamellae have been documented for the first time in cultured recloned squamous cell carcinoma of the head and neck, which had not been subjected to prior chemical treatment. The stacks of annulate lamellae are frequently in continuity with cisterns of the rough endoplasmatic reticulum.


Assuntos
Carcinoma de Células Escamosas/ultraestrutura , Neoplasias de Cabeça e Pescoço/ultraestrutura , Membranas Intracelulares/ultraestrutura , Linhagem Celular , Humanos , Neoplasias Laríngeas/ultraestrutura , Microscopia Eletrônica
7.
Histochemistry ; 88(3-6): 357-65, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3366639

RESUMO

Horse milk fat globules (MFGs) and casein micelles were studied using freeze fracturing, freeze etching and thin-section electron microscopy, as well as lectin histochemistry, gel electrophoresis, and Western blotting. Horse MFGs were found to be relatively small, their average volume-surface diameter being about 2.75 microns. The MFG membrane is composed of three layers: an inner proteinaceous coat occasionally having a paracrystalline substructure, a unit membrane, and a prominent filamentous glycocalyx. The last is rich in glycoconjugates, as revealed by its binding of various lectins. In addition, the glycocalyx binds cationized ferritin, which indicates the presence of negative electric charges. Gel electrophoresis revealed the presence of high-molecular-weight glycoproteins in the MFG membrane of horse milk. Such glycoproteins are also present in human MFG membranes but are absent in the bovine MFGs. The casein micelles in horse milk are relatively large, their average volume-surface diameter being about 200 nm.


Assuntos
Caseínas/metabolismo , Cavalos/metabolismo , Leite/metabolismo , Animais , Bovinos , Feminino , Histocitoquímica , Humanos , Lectinas , Glicoproteínas de Membrana/metabolismo , Micelas , Microscopia Eletrônica , Mucina-1 , Gravidez , Especificidade da Espécie
8.
Tissue Cell ; 19(1): 111-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-18620192

RESUMO

Within the head capsule of the moth-fly Psychoda cinerea, underlying each of the two compound eyes, are two internal ocelli of different sizes. There are seven photoreceptor cells in Ocellus I and two in Ocellus II. The internal Ocellus I appears clearly different from the retina of the compound eye, by different rhabdom structure, different size of pigment granules and different stability of these pigments to solvents. Ocellus II does not contain any pigment granules. The physiological activity of these photoreceptors is indicated by their well-developed axons, the rhabdom structure, organelles produced by membrane reorganization, and adaptation phenomena. The internal ocelli are former larval stemmata that have been displaced inward during metamorphosis. Presumably they have a stimulatory action on the CNS, in analogy with the dorsal ocelli, which are lacking in Psychoda. It is plausible to credit the internal ocelli with a photosensitive role in the functional complex of pacemakers and circadian rhythm.

9.
Acta Anat (Basel) ; 121(2): 69-74, 1985.
Artigo em Alemão | MEDLINE | ID: mdl-3976342

RESUMO

The anlage of the spiral prominence can be seen on the 37th day of development as a small protrusion of the epithelium towards the lumen of the cochlear duct. During the further progress, the spiral prominence more distinctly protrudes by augmentation of the vascularized connective tissue. In the epithelial cells pinocytotic vesicles near the plasmalemma are seen earliest lateral and basal on the 37th day, apical on the 39th day. The epithelial cells send basal cytoplasmic extensions towards the connective tissue. Starting on the 44th day, small invaginations of connective tissue extend into the epithelium, remaining separated from the epithelial cells by the basal lamina. Until the 48th day, the monostratified epithelium remains columnar, thereafter it changes to cuboidal or flat. Towards the end of the development, the invaginations of the connective tissue nearly reach the surface of the epithelium, being separated from the endolymph by a small epithelial area.


Assuntos
Cóclea/embriologia , Ducto Coclear/embriologia , Cobaias/embriologia , Animais , Ducto Coclear/ultraestrutura , Embrião de Mamíferos/anatomia & histologia , Idade Gestacional , Microscopia Eletrônica
10.
Acta Anat (Basel) ; 124(3-4): 159-66, 1985.
Artigo em Alemão | MEDLINE | ID: mdl-4082886

RESUMO

Our studies on exactly dated guinea pig fetuses show: Already in early stages of development (37th day), in the anlage of the vascular stria vesicular invaginations of the apical plasmalemma of epithelial cells are noted and regarded as a sign of an exchange of substances between epithelial cells and the endolymph. As to the direction of substance transport, the morphological finding allows no decision. From the 42nd to the 44th day of development, the subepithelial basal lamina becomes progressively indistinct. From the 45th day onward, the basal lamina is not yet demonstrable. The largest part of the chromophobe cells of the vascular stria derives from the mesenchyme. The question, whether some of the chromophobe cells are of epithelial origin, as some authors propose, will hopefully be clarified in further studies.


Assuntos
Cóclea/embriologia , Ducto Coclear/embriologia , Estria Vascular/embriologia , Animais , Membrana Basal/ultraestrutura , Transporte Biológico , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Ducto Coclear/ultraestrutura , Epitélio/ultraestrutura , Idade Gestacional , Cobaias , Microscopia Eletrônica , Estria Vascular/ultraestrutura
11.
Laryngol Rhinol Otol (Stuttg) ; 63(1): 33-40, 1984 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-6608038

RESUMO

The lack of mucociliary transport causes chronic inflammations in the upper and lower respiratory tract and in the middle ear mucosa. The mucosa of 4 female patients with Kartagener's syndrome was studied by means of TEM (transmission electron microscopy) and SEM (scanning electron microscopy) and compared with the fine structure of normal cilia which were also found in these areas. All specimens studied showed, to a different extent, alterations in the fine structure of the axonemata, especially the absence or malformed ATP-ase dynein arms, the lack of spokes and/or the misarrangement of microtubuli within the cilia. The importance of this congenital anomaly - "immotile cilia" - is discussed with the trias of Kartagener's syndrome.


Assuntos
Cílios/ultraestrutura , Síndrome de Kartagener/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura
12.
Arch Otorhinolaryngol ; 237(3): 243-54, 1983 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-6870657

RESUMO

Differentiation of the Reissner's membrane (membrana vestibularis) is described in precisely dated guinea pig fetuses. In newborn and adult animals, the Reissner's membrane consists of two layers of flat cells, an epithelial one and a mesenchymal one, separated by a basement membrane. The epithelial part develops from the initially simple columnar epithelium of the upper wall of the cochlear duct. The mesenchymal part arises from the embryonic connective tissue, which in early developmental stages occupies the space of the later scala vestibuli. The studies show that during fetal life, a mixture of the endolymph of the cochlear duct with the perilymph of the scala vestibuli is prevented by zonulae occludentes between the epithelial cells of Reissner's membrane. On the other hand, even at an early stage an exchange of material between the two fluids is to a small extent possible by means of cytopempsis through the cytoplasm of the epithelial cells.


Assuntos
Cóclea/ultraestrutura , Ducto Coclear/ultraestrutura , Animais , Feto , Cobaias , Membranas/ultraestrutura , Microscopia Eletrônica
13.
Anat Embryol (Berl) ; 155(3): 303-10, 1979 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-453546

RESUMO

The development of the interdental cells of the limbus spiralis and of the inner spiral sulcus cells as well as the formation of the mesenchymal teeth of Huschke are described during fetal life up to the day of birth in the guinea pig. Additionally, the changes of the developing tectorial membrane are studied. The ultrastructural observations allow the conclusion that during fetal development at least a considerable part of the material of the tectorial membrane is secreted by the interdental cells of the limbus spiralis.


Assuntos
Cóclea/embriologia , Cobaias/embriologia , Animais , Cóclea/ultraestrutura , Microscopia Eletrônica , Membrana Tectorial/embriologia , Membrana Tectorial/ultraestrutura
14.
Cell Tissue Res ; 196(3): 367-84, 1979 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-378381

RESUMO

The location, cytology and projections of vasopressin-, oxytocin-, and neurophysin-producing neurons in the guinea pig were investigated using specific antisera against vasopressin, oxytocin or neurophysin in the unlabeled antibody enzyme immunoperoxidase method. Light microscopic examination of the neurons of the supraoptic and paraventricular nuclei shows that hormone is transported not only in axons, but also in processes having the characteristics of dendrites. Neurons were found to contain only vasopressin or oxytocin; all neurons containing neurophysin appear to contain either vasopressin or oxytocin. In the neural lobe, vasopressin and oxytocin terminals are intermingled. In the median eminence, vasopressin and oxytocin fibers are intermingled in the internal zone. In a caudal portion of the median eminence, a number of vasopressin and neurophysin (but few oxytocin) axons enter the external zone from the internal zone, and surround portal capillaries. In the supraotic nucleus, vasopressin neurons outnumber oxytocin neurons with a ratio of at least 5:1. The paraventricular nucleus is separated into two distinct groups of neurons, a lateral group consisting of only vasopressin neurons, and a medial group consisting of only oxytocin neurons. In addition to axons passing to the neurohypophysis, a number of axons appear to interconnect the supraoptic and paraventricular nuclei.


Assuntos
Sistema Hipotálamo-Hipofisário/citologia , Neurônios/citologia , Animais , Feminino , Cobaias , Técnicas Imunoenzimáticas , Masculino , Neurônios/metabolismo , Neurofisinas/biossíntese , Ocitocina/biossíntese , Núcleo Hipotalâmico Paraventricular/citologia , Núcleo Supraóptico/citologia , Vasopressinas/biossíntese
15.
Arch Otorhinolaryngol ; 221(2): 123-33, 1978 Sep 28.
Artigo em Alemão | MEDLINE | ID: mdl-751617

RESUMO

In early stages of fetal development (36th day, 3rd turn) the thickening of the epithelium at the basal side of the cochlear duct forms two ridges. Later in fetal development the laterally situated lesser epithelial ridge forms the major part of the organ of Corti, whereas the medially situated greater epithelial ridge contributes only a small part to this organ. The medial part of the greater ridge consists of the columnar inner supporting cells, which bear a border of closely packed microvilli at their upper surface. Up to the time of the opening of the internal spiral sulcus in the 48th day of fetal development, there is a close spacial relationship between microvilli and filaments of the tectorial membrane. We conclude that the inner supporting cells contribute to the formation of the tectorial membrane. However, thus far we cannot entirely exclude a different possibility, that the inner supporting cells absorb material of the tectorial membrane. During the opening of the sulcus spiralis internus the inner supporting cells become considerably smaller, some of them undergo complete destruction by cytolysis, with pyknosis and karyorrhexis.


Assuntos
Cóclea/embriologia , Membrana Tectorial/embriologia , Animais , Cobaias , Células Labirínticas de Suporte/embriologia , Células Labirínticas de Suporte/ultraestrutura , Lâmina Espiral/embriologia , Lâmina Espiral/ultraestrutura , Membrana Tectorial/ultraestrutura
16.
Arch Otorhinolaryngol ; 218(3-4): 179-90, 1978 Jan 30.
Artigo em Alemão | MEDLINE | ID: mdl-580175

RESUMO

Surface alterations of the stria vascularis and Reissner's membrane were studied in guinea pigs following intravenous or intraperitoneal administration of ethacrynic acid or atoxyl. DC-potential was measured in the same animals during intoxication. In addition we studied changements in potassium concentration (perilymph, endolymph) of the atoxyl-treated animals.


Assuntos
Arsenicais/efeitos adversos , Cóclea/efeitos dos fármacos , Ácido Etacrínico/efeitos adversos , Potenciais de Ação/efeitos dos fármacos , Compostos de Anilina/efeitos adversos , Animais , Cóclea/citologia , Cóclea/fisiopatologia , Ácido Etacrínico/administração & dosagem , Cobaias
19.
Arzneimittelforschung ; 26(6): 1191-4, 1976.
Artigo em Alemão | MEDLINE | ID: mdl-989414

RESUMO

Vasopressin (VP) can be shown to exert psychotropic effects independent of its antidiuretic activity, facilitating learning and consolidation of memory in rats. Immunoreactive VP and neurophysin (NP) are localized on serial section of Bouin fixed, paraffi embedded guinea pig, rat and hamster brains. Localization was not restricted to the classical sites of supraoptic and paraventricular nucleus, medianeminence and neurohypophysis...


Assuntos
Hipotálamo , Neurofisinas/análise , Vasopressinas/análise , Animais , Encéfalo/efeitos dos fármacos , Cricetinae , Cobaias , Hipotálamo/análise , Vias Neurais , Ratos , Núcleos Septais/análise , Lobo Temporal/análise , Tálamo/análise , Vasopressinas/farmacologia
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