RESUMEN

Cell junctions and the cytoskeleton of integumental epidermal cells from six bivalves, four gastropods, and two cephalopods were studied by transmission electron microscopy. In all species examined, the junctions in supporting cells presented the following similar pattern: an apical-lateral adhesion belt (occluding junctions were not observed); (b) a lateral complex of septate junctions and smooth septate junctions, with interdigitations between adjacent cells while the gap junctions were not constantly present, and a basal complex with hemidesmosomes, focal contacts, and sometimes basolateral adherent junctions. Desmosomes were never observed. Microfilamentous and microgranular material were present throughout the cells, as bundles of microfilaments within microvilli and the terminal web, within interdigitations, and as cytoplasmic plaques forming part of the adherent junctions, hemidesmosomes, and focal contacts. Bundles of intermediate filaments that originated from basal hemidesmosomes were located close to and oriented parallel with the lateral plasma membrane and terminated within the terminal web. In cells of Aplysia depilans, intermediate filaments converged apically to terminate in hemidesmosome-like structures at the bases of the microvilli. In the cephalopods, hemidesmosomes were never observed and intermediate filaments made direct contact with the basal cell membrane. Some functional interpretations and hypotheses were also discussed.

Asunto(s)

Citoesqueleto/ultraestructura , Células Epiteliales/ultraestructura , Uniones Intercelulares/ultraestructura , Moluscos/ultraestructura , Animales , Integumento Común , Microscopía Electrónica de Transmisión

RESUMEN

The protein p27BBP (alias eIF6) occurs in yeast and mammalian epithelial cells. It is essential for ribosome genesis and has also been implicated in the functionality of integrins and intermediate filaments. By immunoblot, we show that homogenized integument from Sepia officinalis (Cephalopoda, Mollusca) contains a protein with immunological properties that closely resemble those of p27BBP. We also demonstrate, by immunogold electron microscopy with an indirect immunoreaction technique on ultrathin sections of human skin and Sepia integument, that p27BBP is constantly present in both species in epithelial cells, fibroblasts, and muscle fibers. It is found in the vicinity of intermediate filaments, in nucleoli, along the internal wall of the nuclear membrane, and in association with desmosomes and hemidesmosomes and occasionally occurs extracellularly. Thus, the structure and function of p27BBP seem to have been highly conserved throughout evolution; the protein appears to be essential in eukaryotic cells in which it interacts with several ultrastructural components of diverse function.

Asunto(s)

Proteínas Portadoras/metabolismo , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/metabolismo , Moluscos/química , Piel/metabolismo , Anciano , Animales , Proteínas Portadoras/química , Proteínas Portadoras/ultraestructura , Células Epiteliales/metabolismo , Células Epiteliales/ultraestructura , Factores Eucarióticos de Iniciación , Fibroblastos/metabolismo , Fibroblastos/ultraestructura , Células HeLa , Humanos , Proteínas de Filamentos Intermediarios/química , Proteínas de Filamentos Intermediarios/ultraestructura , Masculino , Microscopía Confocal , Microscopía Electrónica , Moluscos/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/ultraestructura , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas Nucleares/ultraestructura , Peroxidasas/metabolismo , Pruebas de Precipitina , Piel/ultraestructura

RESUMEN

Our previous electron microscope study showed that chondrocytes from cephalopod cartilage possess a highly developed cytoskeleton and numerous cytoplasmic processes that ramify extensively through the tissue. We have now carried out a light microscope immunocytochemical study of chondrocytes from the orbital cartilage of Sepia officinalis to obtain indications as to the nature of the cytoskeletal components. We found clear positivity to antibodies against mammalian tubulin, vimentin, GFAP, and actin, but not keratin. The simultaneous presence of several cytoskeletal components is consistent with the hypothesis that cephalopod chondrocytes have the characteristics of both chondrocytes and osteocytes of vertebrates, which endow the tissue as a whole with some of the properties of vertebrate bone. We confirm, therefore, the presence in molluscs of the ubiquitous cytoskeletal proteins of metazoan cells that have remained highly conserved throughout phylogenetic evolution.

Asunto(s)

Condrocitos/química , Citoesqueleto/química , Faloidina/análogos & derivados , Animales , Anticuerpos/análisis , Especificidad de Anticuerpos , Cartílago/química , Cartílago/efectos de los fármacos , Cartílago/ultraestructura , Pollos , Condrocitos/efectos de los fármacos , Condrocitos/ultraestructura , Citoesqueleto/efectos de los fármacos , Citoesqueleto/ultraestructura , Humanos , Inmunohistoquímica/métodos , Técnicas In Vitro , Moluscos/química , Faloidina/farmacología , Ratas , Rodaminas/farmacología

RESUMEN

Collagen fibrils from the dermis of Sepia officinalis were processed for immunoelectron microscopy to reveal reactions to antibodies against mammalian types I, III, and V, teleost type I and cephalopod type I-like collagens, by single and double immunogold localization. The fibrils were observed: (a) in suspensions of prepared fibrils, (b) in ultrathin sections of embedded fibril preparations, and (c) in ultrathin sections of dermal tissue. Some samples were subjected to acetic acid or urea dissociation. It was found that collagen fibrils from Sepia dermis are heterotypic in that they are composed of type I-like and type V collagens. Type I-like collagen epitopes were present mainly at the periphery of the fibrils; type V collagen epitopes were present throughout the fibrils. This is the first demonstration that collagen fibrils from an invertebrate are heterotypic, suggesting that heterotypy may be an intrinsic characteristic of the fibrils of fibrillar collagens, independent of evolutionary or taxonomic status.

Asunto(s)

Colágenos Fibrilares/química , Moluscos/química , Animales , Anticuerpos/inmunología , Colágenos Fibrilares/inmunología , Colágenos Fibrilares/ultraestructura , Microscopía Inmunoelectrónica , Moluscos/metabolismo

RESUMEN

We studied structure and ultrastructure of the subepidermal connective tissue (SEC) of the integument of three cephalopods (Sepia officinalis, Octopus vulgaris and Loligo pealii). In all species, three distinct regions of the SEC were recognised: (a) an outer zone (OZ) that included the dermal-epidermal junction, and consisted of a thin layer of connective tissue containing muscles, (b) an extensive middle zone (MZ) containing a compact network of collagen fibres and numerous cells, (c) an inner zone (IZ) of loose connective tissue that merged with muscular fascia. This arrangement differs from that in bivalves and gastropods and recalls vertebrate integument. The dermal-epidermal junction of cephalopods differed from that of bivalves, gastropods and mammals in that the epidermal cells did not possess hemidesmosomes, and their intermediate filaments terminated directly in the plasmamembrane. The thick (120-500 nm) basal membrane (BM) had a superficial zone containing a regular array of granules; a lamina densa composed of a compact network of small filaments and granules; and an IZ distinguished by expansions of granular material protruding into underlying structures. Collagen fibres contained fibroblast-derived cytoplasmic thread, running through their centres and were surrounded by granular material that joins them to adjacent fibres. The collagen fibrils were of medium diameter (30-80 nm) had the typical ultrastructure of fibrillar collagens, and were surrounded by abundant interfibrillar material. The hypodermis was loose, with a network of small bundles of collagen fibrils. Cephalopod integument appears to represent a major evolutionary step distinguishing this class of molluscs.

Asunto(s)

Tejido Conectivo/ultraestructura , Integumento Común/anatomía & histología , Moluscos/ultraestructura , Animales , Membrana Basal/ultraestructura , Evolución Biológica , Colágeno/ultraestructura , Decapodiformes/ultraestructura , Dermis/ultraestructura , Epidermis/ultraestructura , Microscopía Electrónica , Octopodiformes/ultraestructura , Especificidad de la Especie

RESUMEN

Sections of integument from gastropod, bivalve and cephalopod species were studied immunohistochemically to determine reactivity to antibody against the type I-like collagen from Sepia cartilage and antibodies against components of the extracellular matrix (ECM) of vertebrate connective tissue: type I, III, IV, V, and VI collagens, laminin, nidogen and heparan sulphate. All samples exhibited similar reactivities to the antibodies, although differences in the intensity and localization of the immunostaining were found that were clearly correlated with between-species differences in integumental ultrastructure. These findings indicate that the composition of the integumental ECM is similar in the three classes of molluscs examined and that several types of collagen are present. However molluscan subepidermal connective tissue differs from the ECM of vertebrate dermis: molluscan integumental ECM contains collagens similar to type I, V and VI collagens but has no type III-similar collagen. Furthermore molecules similar to the type IV collagen, laminin, nidogen and heparan sulphate of vertebrates were present ubiquitously in molluscan basement membrane, confirming the statement that the structure and composition of basement membrane have remained constant throughout the evolution of all animal phyla.

Asunto(s)

Tejido Conectivo/metabolismo , Moluscos/metabolismo , Animales , Especificidad de Anticuerpos , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo IV/metabolismo , Colágeno Tipo V/metabolismo , Colágeno Tipo VI/metabolismo , Tejido Conectivo/enzimología , Peces , Técnica del Anticuerpo Fluorescente Indirecta , Heparitina Sulfato/metabolismo , Humanos , Inmunohistoquímica , Laminina/metabolismo , Glicoproteínas de Membrana/metabolismo , Ratones , Moluscos/anatomía & histología , Adhesión en Parafina , Ratas , Coloración y Etiquetado , Fijación del Tejido

RESUMEN

Electrophoretic and Western blot studies were conducted on collagen fractions extracted from Sepia officinalis (cuttlefish) cartilage using a modified salt precipitation method developed for the isolation of vertebrate collagens. The antibodies used had been raised in rabbit against the following types of collagen: Sepia I-like; fish I; human I; chicken I, II, and IX; rat V; and calf IX and XI. The main finding was that various types of collagen are present in Sepia cartilage, as they are in vertebrate hyaline cartilage. However, the main component of Sepia cartilage is a heterochain collagen similar to vertebrate type I, and this is associated with minor forms similar to type V/XI and type IX. The cephalopod type I-like heterochain collagen can be considered a first step toward the evolutionary development of a collagen analogous to the typical collagen of vertebrate cartilage (type II homochain). The type V/XI collagen present in molluscs, and indeed all phyla from the Porifera upwards, may represent an ancestral collagen molecule conserved relatively unchanged throughout evolution. Type IX-like collagen seems to be essential for the formation of cartilaginous tissue.

Asunto(s)

Cartílago/química , Colágeno/aislamiento & purificación , Moluscos/química , Animales , Fraccionamiento Químico , Precipitación Química , Colágeno/análisis , Electroforesis en Gel de Poliacrilamida , Immunoblotting , Cloruro de Sodio

RESUMEN

We studied the ultrastructure of the subepidermal connective tissue (SEC) in different zones of the integument in terrestrial, marine and freshwater gastropods (eight species). In all cases, the SEC was a layer of loose connective tissue between the basal membrane (BM) of the epidermis and the connective tissue of the deeper muscle layers. It was of monotonous structure and not differentiated into layers such as are found in mammalian dermis. The extracellular matrix (ECM) consisted of a network of collagen fibrils of variable diameter, with abundant anchoring devices and proteoglycans. In six species, variables quantities of haemocyanin were present within haemocoelic sinuses present in the SEC. The thickness and density of the BM varied from species to species, as well as within species in the various zones of integument. The ultrastructure of the lamina densa (LD) was indistinguishable from that of BM in bivalves and similar to that in mammals, although basotubules and double pegs were absent. An irregularly spaced lamina lucida was usually present and was often shot thorough with filaments and small protrusions of the LD that connected with epithelial plasma membrane or with hemidesmosomes. A lamina fibroreticularis was not present. LD protrusions characterize the connection between BM and the ECM of SEC. In the terrestrial gastropods, a spongy matrix with ultrastructure closely similar to LD occupied large tracts of the SEC. In the mantle region of Arion rufus, the integumental SEC contained large cavities filled with spherical concretions, probably representing rudiments of a shell. In the mantle where the integument contained abundant muscle fibres, the BM was thick and directly connected to the ECM of the SEC which consisted of compact laminae of collagen fibrils with abundant anchoring devices. Along the edge of the foot of Patella ulyssiponensis, the SEC contained a layer of paramyosinic muscle fibres adhering to the epidermis. No differences or gradations in integumental SEC structure could be related to the phylogenetic position of the species examined.

Asunto(s)

Tejido Conectivo/ultraestructura , Moluscos/ultraestructura , Animales , Membrana Basal/ultraestructura

RESUMEN

The ultrastructure of the subepidermal connective tissue (SEC) in different areas of the integument of the bivalves Callista chione, Pecten jacobaeus, Mytilus galloprovincialis and Ostrea edulis was studied by transmission electron microscopy. The main organisation of the SEC was broadly similar in all species: the SEC was connected to the epidermis by a basement membrane and merged directly with the deeper connective tissue surrounding muscles. The SEC was not differentiated into layers like the papillary and reticular dermis of mammals, however, the architecture, thickness and shape of the basement membrane varied from species to species, as well as within species (in the foot, central or marginal zones of the mantle). The ultrastructure of the lamina densa was broadly similar to that in mammals: although basotubules and double pegs were absent, proteoglycans and rod-like units homologous to 'double tracks' were always abundant. A zone similar to the lamina lucida was irregularly present and was shot thorough with small protrusions of the lamina densa that connected with the epithelial hemidesmosomes or focal adhesions. Nevertheless zones were observed where the lamina densa fuse directly to the epithelial plasmamembrane. This variability of connection may be related to the various types of epidermal cell. A lamina fibroreticularis was not recognized since anchoring fibrils and microfibrils were not present; lamina densa protrusions into the extracellular matrix (ECM) of SEC characterize the connection between basement membrane and SEC. Collagen fibrils were small and of constant diameter and were never organised into fibres. Anchoring devices - similar to the anchoring plaques of mammalian dermis - were abundant and scattered between SEC collagen fibrils. The orange-pink pigmentation of C. chione seems due to electron-dense granules embedded within the connective ECM.

Asunto(s)

Tejido Conectivo/ultraestructura , Epidermis/ultraestructura , Moluscos/fisiología , Moluscos/ultraestructura , Animales , Membrana Basal/ultraestructura , Membrana Celular/química , Membrana Celular/ultraestructura , Colágeno/química , Tejido Conectivo/fisiología , Epidermis/fisiología , Matriz Extracelular/química , Matriz Extracelular/ultraestructura , Microscopía Electrónica , Proteoglicanos/química , Especificidad de la Especie

RESUMEN

We used various anti-collagen antibodies to perform indirect immunofluorescent staining of cartilage sections from cuttlefish (S. officinalis). On ultrathin sections and collagen fibril preparations from the same tissue, we performed immunostaining with colloidal gold. The extracellular matrix (ECM) of S. officinalis cartilage reacted intensely and homogeneously with an antibody directed against type I-like collagen isolated from the cartilage of cuttlefish and with anti-rat type V collagen antibody. A weak reaction was observed with anti-fish and anti-chicken type I collagen antibodies, while no reaction was observed with anti-rat type I and anti calf type II collagen antibodies. Anti-chicken type II, anti calf type IX and type XI collagen antibodies reacted weakly with ECM, while stained cell bodies and cell processes reacted more intensely. A similar pattern of reaction was observed on cartilage section and isolated collagen fibrils prepared for electron microscopy. These findings suggest that ECM of cuttlefish cartilage may be composed of molecules similar to the type I, type V, type IX and type XI collagen molecules of vertebrates. Cephalopods have evolved a cartilage of structure and macromolecular organisation similar to that of vertebrate cartilage. However, the main molecular components of S. officinalis cartilage--type I-like and type V collagens--differ from those of vertebrate cartilage. We suggest that this type I-like collagen can be considered an initial step toward the evolution of type II collagen typical of vertebrates.

Asunto(s)

Cartílago/metabolismo , Colágeno/inmunología , Colágeno/metabolismo , Matriz Extracelular/inmunología , Moluscos , Animales , Anticuerpos/metabolismo , Cartílago/ultraestructura , Condrocitos/metabolismo , Condrocitos/ultraestructura , Colágeno/ultraestructura , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestructura , Técnica del Anticuerpo Fluorescente Indirecta , Inmunohistoquímica , Microscopía Electrónica , Especificidad de la Especie

RESUMEN

Collagen fibrils isolated from sternal cartilage of chick embryo and chondrocranium of cuttle-fish (Sepia officinalis) were examined with the electron microscope after rotary showing. The aim was to determine whether collagen fibrils from S. officinalis cartilage contained collagen molecules similar to the type IX collagen of vertebrate cartilage. Cartilage from both sources presented a highly variable appearance and only occasionally did preparations contain fibrils having the structure described by Vaughan et al. (1988) for vertebrate cartilage. Subsequent electron microscope investigation of collagen samples during the various stages of fibril preparation showed that the method did not yield reproducible results, and that is altered the morphology of the isolated structures. It was not, therefore, possible to confirm the hypothesis that collagen molecules with a morphology similar to that type IX vertebrate collagen are a component of the extracellular matrix of cephalopod cartilage.

Asunto(s)

Cartílago/ultraestructura , Colágeno/ultraestructura , Matriz Extracelular/ultraestructura , Animales , Cartílago/química , Embrión de Pollo , Pollos , Matriz Extracelular/química , Microscopía Electrónica , Moluscos

RESUMEN

Thin sections of cartilage from the chondrocranium of cuttle fish and octopus were examined using the transmission electron microscope. It was found that cephalopod chondrocytes differed considerably from the chondrocytes of vertebrate cartilage; in particular they possessed many long and ramifying cytoplasmic processes and had an ultrastructure typical of protein-secreting cells. They did not, however, contain secretory granules; while vesicles and rough endoplasmic reticulum cisternae seemed to open directly to the cell surface. The cell body and processes contained cytoskeletal structures: microtubules were easily recognized, but intermediate and thin filaments were difficult to make out as they were frequently clumped into bundles. Some chondrocytes contained conspicuous accumulations of hemocyanin. The cytoplasmic processes possessed intercellular contacts similar to gap junctions. Also present on processes and the cell body were cell-extracellular matrix focal adhesions. The chondrocytes were not polarized or arranged in any preferential spatial order, however, with their processes they formed a three-dimensional network throughout the cartilage tissue. Ultrastructural findings are discussed in relation to the singular morphofunctional characteristics of cephalopod cartilage which shares features with both the cartilage and bone of vertebrates.

RESUMEN

The general organization, cellular and extracellular components, and structural variation of perichondrium have been studied in different mammalian cartilages by polarized light and transmission electron microscopy. The overall structure is that of a dense connective tissue composed of variable numbers of thin, stratified, closely-packed lamellae, themselves composed of closely-matted collagen fibres running in the plane of the cartilage surface, but oriented at various angles to each other. Variations mainly concern the arrangement of the fibre bundles in the transition zones between perichondrial and cartilage matrices, and between perichondrium and surrounding tissues. Perichondrial cells have the characteristics of fibrocytes. A cambial layer of undifferentiated stem cells was never observed. A layer of 'perichondrial lining cells' with distinctive ultrastructural characteristics was observed in some cartilage units, which separates the perichondrium from the surrounding loose connective tissue. The ultrastructural results demonstrate that the cartilage and perichondrial extracellular matrices are distinct, and what have been designated perichondrial 'transition' and 'proliferative' zones are in fact parts of the most superficial cartilage layer. Variations in perichondrial structure appear to correlate with diversity of cartilage function and we conclude that each cartilage unit plus perichondrium forms a tightly-integrated entity, best regarded as a unitary organ within the skeletal system.

Asunto(s)

Cartílago/citología , Cartílago/ultraestructura , Adulto , Animales , Cartílago/química , Colágeno/análisis , Oído Externo/química , Oído Externo/ultraestructura , Matriz Extracelular/química , Humanos , Mamíferos , Ratones , Microscopía Electrónica , Microscopía de Polarización , Microtomía , Persona de Mediana Edad , Nariz/ultraestructura , Conejos , Ratas , Ratas Sprague-Dawley , Costillas/ultraestructura , Tráquea/citología

RESUMEN

The ultrastructure of perichondrial tissue of cartilage rudiments (metatarsus, tibiotarsus and sternum) of the chick embryo at various stages of development (H.H. stages 28-45) was investigated by transmission electron microscopy. Previous microscopic and submicroscopic data were generally confirmed, but new findings indicated: (a) the existence of a temporary syncytial state of perichondroblasts during the earliest developmental stages, (b) the existence of a perichondrial cambial layer of stem cells, (c) involvement of perichondroblasts in the appositional growth of cartilage. Electron microscopy revealed clear temporal relations between cell differentiation, perichondrial growth and the structure and production of perichondrial ECM. In addition, the boundaries between cartilage and perichondrial tissue were demonstrated unambiguously. Perichondrial structure varied specifically with each cartilage segment; in particular the perichondrium in long bone rudiments (where ossification starts early) contrasted with that in the permanent cartilage medial process of the sternum.

Asunto(s)

Cartílago/embriología , Cartílago/ultraestructura , Miembro Posterior/ultraestructura , Esternón/ultraestructura , Factores de Edad , Animales , Embrión de Pollo , Diáfisis/embriología , Diáfisis/ultraestructura , Matriz Extracelular/ultraestructura , Miembro Posterior/embriología , Uniones Intercelulares/ultraestructura , Mesodermo/ultraestructura , Microscopía Electrónica , Esternón/embriología

RESUMEN

The microscopic and submicroscopic structures of perichondrial tissues in the head cartilages of Octopus vulgaris were studied by polarized light and transmission electron microscopy. The orbital cartilages possess a birefringent layer parallel to the surface of the cartilage; ultrastructurally, this layer, which may be considered perichondrial tissue, has the typical organisation of connective tissue but does not possess the stratification of collagen laminae found in vertebrate perichondria. Perichondrial extracellular matrix is clearly distinct from that of cartilage because its collagen fibrils are of a larger diameter than collagen fibrils from cartilage. In addition, perichondrial fibroblasts are characteristically located at the center of collagen fibers. In the cerebral cartilage, the perichondrium is absent or discontinuous in relation to complex interconnections between cartilage and connective fibres, muscle fibres, blood vessels and nerve. Distinctive cartilage-lining cells, rich in electron dense cytoplasmatic granules, are stratified either along the cartilage surface or along vessels and muscle fibres that penetrate within the cartilage. The perichondrium of cephalopod cartilage, whose structure varies according to the location and function of its skeletal segments, mimics that of vertebrate perichondrium, exemplifying the high level of tissue differentiation attained by cephalopods.

RESUMEN

Native collagen fibrils were isolated from cephalopod head cartilage and mammal hyaline cartilage. The analysis with TEM after positive and negative staining demonstrated that the fibrils have a periodic structure similar to that of fibrillar type I collagen of mammals. The banding pattern of polymeric forms (SLS, FLS) obtained in vitro from squid cartilage collagen was remarkably different from the analogous forms of mammal collagen types I and II.

Asunto(s)

Cartílago/ultraestructura , Colágeno/ultraestructura , Moluscos/anatomía & histología , Animales , Microscopía Electrónica , Conejos

RESUMEN

It has been demonstrated that the semen of infertile patients contains at high percentage of abnormal forms and no clear answer has been so far provided to the questions of which malformations are compatible with male fertility, which malformations are responsible for the infertility and which is the percentage of defective cells that gives rise to infertility. In this study the eiaculates of 56 patients of suspected male infertility were used as material. The semen samples were fixed for 2 hr at room temperature in 4% glutaraldehyde in 0.05 M cacodilate buffer + 0.018% CaCl2 + 6.6% sucrose, post-fixed in 1.5% OsO4 in same buffer + 6.6% sucrose, dehydrated and embedded in Spurr. The samples were sectioned with Reichert OMu3 ultratome. The sections, contrasted with uranyl acetate and lead citrate, were examined in a Feol M T8 E.M. The varieties of sperm malformations are described and classificated into morphological categories based upon the type of alteration and the cellular portion in which the malformation appeared. From this research we have got the following conclusions: 1) an absolute correlation between microscopical, ultrastructural defects and functionality of spermatozoa does not exists; 2) the submicroscopic analysis contributes to a more accurate definition of the eiaculate; 3) the high variability of the ultrastructural defects needs that the submicroscopical analysis of the human semen must be supplemented by a quantitative evaluation.

Asunto(s)

Infertilidad Masculina/patología , Espermatozoides/ultraestructura , Humanos , Masculino , Microscopía Electrónica , Cabeza del Espermatozoide/anomalías , Cabeza del Espermatozoide/ultraestructura , Cola del Espermatozoide/anomalías , Cola del Espermatozoide/ultraestructura , Espermatozoides/anomalías

RESUMEN

Serotonin has been localized in neurons of the pedal ganglion of Mytilus galloprovincialis by means of colloidal gold immunostaining. Ultrastructural quantitative analysis shows that gold particles are concentrated over perikarya and fibers containing a unique vesicle population. The vesicles are round or elliptical with a diameter ranging from 100 to 180 nm and have a dense core with areas of minor density. Their intense labelling suggests that they are the main cellular compartment where serotonin is stored.

Asunto(s)

Ganglios/análisis , Serotonina/análisis , Animales , Bivalvos , Ganglios/ultraestructura , Inmunohistoquímica , Microscopía Electrónica , Serotonina/inmunología , Coloración y Etiquetado/métodos

RESUMEN

The morphology of head cartilage of the cephalopods Sepia officinalis and Octopus vulgaris has been studied on samples fixed and embedded for light- and electron microscopy and on fresh frozen sections viewed by polarizing microscopy. The organization of extracellular matrix (ECM) varies in different regions of the head cartilage. Superficial zones are made up of densely packed collagenous laminae parallel to the cartilage surface, while radially arranged laminae form a deeper zone where territorial and interterritorial areas are present. A compact arrangement of banded collagen fibrils (10-25 nm in diameter) forms the laminae of the superficial zones and of the interterritorial areas; a loose three-dimensional network of fibrils (10-20 nm) with many proteoglycan aggregates forms the territorial areas. A pericellular matrix surrounds the bodies of extremely branched territorial chondrocytes. Peculiar anchoring devices (ADs) are dispersed with variable orientation within the ECM. A perichondrium is present, but often connectival and muscular bundles are fused with the superficial layers of cartilage. Some vessels were also observed within the superficial inner zone and clusters of hemocyanin molecules were demonstrated both in the ECM and in some cells. The cephalopod head cartilage seems to share some morphological characteristics with both hyaline cartilage and bone tissue of vertebrates.

RESUMEN

A morphological analysis was carried out on testicular biopsies of men with obstructive azoospermia as consequence of vas deferens malformations as compared with biopsies from fertile men. For each case the biopsies were processed with two different techniques: routine histological procedure, and semithin sections of specimens processed for electron microscopy. Four parameters were considered: tubular morphology, testicular biopsy score count (TBSC), tubular diameter, and germinal cell density. The data were quantified and analyzed by statistical tests. The biopsies of azoospermic men present a higher frequency of tubular sections with "tubular blockage," "sloughing" and cellular degeneration, lower values of TBSC, and lower germinal cell density. The results appear to be of relevant interest in relation to the existence of long-term testicular alteration following vasectomy.

Asunto(s)

Oligospermia/patología , Testículo/patología , Conducto Deferente/anomalías , Adulto , Biopsia , Recuento de Células , Humanos , Masculino , Persona de Mediana Edad , Túbulos Seminíferos/patología , Espermatozoides/patología